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Das in Manderen, Departement Moselle, gelegene Schloss von Malbrouck befindet sich genau an der deutschen und luxemburgischen Grenze. Sein Bau wurde nach dem Willen von Arnold VI, dem Grundherrn von Sierck, im Jahre 1419 begonnen, wurde 1434, in dem Jahr, in dem das Schloss für geeignet befunden wurde, einem Angriff widerstehen zu können, vollendet und dann in den Dienst des Erzbistums Trier gestellt.
Unglücklicherweise war zum Zeitpunkt des Todes von Ritter Arnold dessen Nachfolge nicht gesichert, weshalb das Schloss ab Ende des XV. bis Anfang des XVII. Jahrhunderts von einer Hand in die nächste überwechselte.
Seit es im Jahre 1930 unter Denkmalschutz gestellt wurde und der Conseil Général de la Moselle es 1975 von seinem letzten Eigentümer, einem Bauern, zurückkaufte, wurde das Schloss vollständig saniert und im September 1988 wiedereröffnet. Wie jedes andere Bauwerk dieser Größenordnung braucht es eine feine und genaue Überwachung. Aus diesem Grund wollte der Conseil Général de la Moselle strategischer Partner im Projekt CURe MODERN werden.
Die Brücke von Rosbrück ist ein Bauwerk aus Spannbeton, das vom Departement Moselle verwaltet wird. Da sie schon 1952 gebaut wurde, weist sie mehrere Spannkabel auf, die offensichtlich rissig oder brüchig sind. Diese Schädigungen stellen die Tragfähigkeit des Bauwerks in Frage.
Es erschien daher notwendig, den Zustand der Kabel im Inneren der Träger zu überprüfen. Im Vorfeld der Kontrolle mittels der MFL-Methode (Magnetic Flux Leakage) wurde deren Position im Verhältnis zu den Ausführungsebenen überprüft. Da diese Überprüfung schlüssig war, wurden dann die MFL-Messungen an einem der Träger des Bauwerks durchgeführt. Die Ergebnisse sind beweiskräftig und es wurden keine Mängel nachgewiesen. In der Folge erscheint es nötig, die Überprüfung (Auskultation) auf geschädigte Bereiche auszudehnen.
In der Betriebswirtschaftslehre bestehen unterschiedliche Sichtweisen in Bezug auf Unternehmensziele und deren Verhältnis zu Stakeholderzielen. Der vorliegende Beitrag untersucht das Verhältnis von Unternehmenszielen und Stakeholderzielen, wobei die zentrale Zielsetzung des Beitrags darin besteht, die Stakeholderziele zu spezifizieren, da bislang existierende Kataloge mit Stakeholderzielen wenig detailliert sind. Dabei werden die unterschiedlichen Stakeholderziele anhand ihrer drei Zieldimensionen untersucht sowie in Formal- und Sachziele unterteilt. Des Weiteren wird deutlich, dass zwischen Unternehmenszielen und Stakeholderzielen durch die differierenden Ziele der unterschiedlichen Stakeholdergruppen ständige Konflikte herrschen, wodurch es grundsätzlich innerhalb unter-nehmerischer Zielsysteme nur zu einer Quasilösung der Konflikte kommen kann.
Zerstörungsfreie (ND) Erkundungstechniken, seien es nun zerstörungsfreie oder geophysikalische Bewertungsmethoden, werden üblicherweise im Bau- und Transportwesen, im Bereich der Energietechnik oder der Stadtentwicklung angewandt. Während sich jedoch im Laufe der letzten Jahrzehnte das Interesse auf interne geometrische Informationen zu der untersuchten Umgebung richtete, konzentrieren sich jüngere Forschungen auf Informationen, die mit der Art und dem Zustand dieser Umgebung verbunden sind, um so dem Begiff der zerstörungsfreien Bewertung näher zu kommen. Die gegenwärtig laufenden Studien versuchen, die aus zerstörungsfreien Messungen abgeleiteten Werte in statistische, mit Lebensdauermodellen verknüpfte Ansätze zu integrieren.
Without actors, there is no action: How interpersonal interactions help to explain routine dynamics
(2020)
In this paper, we argue that it is important to gain a better understanding on how people interact with each other to explain routine dynamics. Thus, we propose to focus on the interpersonal interactions of actors which is not only the fact that actors interact with each other but that the manner and quality of these interactions is important to understand routine dynamics. By drawing on social exchange theory, we propose a framework that seeks to explain routine dynamics based on different relationships between actors. Building on this framework, we provide different process models indicating how routine performing and patterning is enacted due to the respective relationship of actors. Our insights contribute to research on routine dynamics by arguing (1) that actions of patterning are dependent on the relationship of actors; (2) that trust works as an enabler for creating new patterns of actions; (3) that distrust functions as an enhancer for interrupting and dissolving patterns of actions.
Aufgrund der vernetzten Strukturen und Wirkungszusammenhänge dynamischer Systeme werden die zugrundeliegenden mathematischen Modelle meist sehr komplex und erfordern ein hohes mathematisches Verständnis und Geschick. Bei Verwendung von spezieller Software können jedoch auch ohne tiefgehende mathematische oder informatorische Fachkenntnisse komplexe Wirkungsnetze dynamischer Systeme interaktiv erstellt werden. Als Beispiel wollen wir schrittweise das Modell einer Miniwelt entwerfen und Aussagen bezüglich ihrer Bevölkerungsentwicklung treffen.
Die Akustik liefert einen interessanten Hintergrund, interdisziplinären und fächerverbindenen Unterricht zwischen Mathematik, Physik und Musik durchzuführen. SchülerInnen können hierbei beispielsweise experimentell tätig sein, indem sie Audioaufnahmen selbst erzeugen und sich mit Computersoftware Frequenzspektren erzeugen lassen. Genauso können die Schüler auch Frequenzspektren vorgeben und daraus Klänge erzeugen. Dies kann beispielsweise dazu dienen, den Begriff der Obertöne im Musikunterricht physikalisch oder mathematisch greifbar zu machen oder in der Harmonielehre Frequenzverhältnisse von Intervallen und Dreiklängen näher zu untersuchen.
Der Computer ist hier ein sehr nützliches Hilfsmittel, da der mathematische Hintergrund dieser Aufgabe -- das Wechseln zwischen Audioaufnahme und ihrem Frequenzbild -- sich in der Fourier-Analysis findet, die für SchülerInnen äußerst anspruchsvoll ist. Indem man jedoch die Fouriertransformation als numerisches Hilfsmittel einführt, das nicht im Detail verstanden werden muss, lässt sich an anderer Stelle interessante Mathematik betreiben und die Zusammenhänge zwischen Akustik und Musik können spielerisch erfahren werden.
Im folgenden Beitrag wird eine Herangehensweise geschildert, wie wir sie bereits bei der Felix-Klein-Modellierungswoche umgesetzt haben: Die SchülerInnen haben den Auftrag erhalten, einen Synthesizer zu entwickeln, mit dem verschiedene Musikinstrumente nachgeahmt werden können. Als Hilfsmittel haben sie eine kurze Einführung in die Eigenschaften der Fouriertransformation erhalten, sowie Audioaufnahmen verschiedener Instrumente.
Monitoring of patient-reported outcomes and providing therapists with progress feedback has been shown to be beneficial for treatment outcomes (e.g., by preventing therapy failures). Despite recent advances in monitoring and feedback research, little is known about why some therapists benefit from feedback more than others. Addressing this issue, the present article uses the basic science literature on belief updating to propose a theoretical model for these between-therapist differences. In doing so, we provide a novel framework that allows testable hypotheses about when and how feedback on therapy progress is likely to improve treatment outcomes. In particular, we argue that the integration of feedback and its effect on therapists’ behavior depends on the weight therapists assign to their prior beliefs regarding treatment progress relative to the weight of the feedback received. We conclude by outlining some directions for future research on the underpinnings of this model, and point to some implications for the training of therapists and provision of feedback.
Whole-body electromyostimulation (WB-EMS) is an extension of the EMS application known in physical therapy. In WB-EMS, body composition and skinfold thickness seem to play a decisive role in influencing the Ohmic resistance and therefore the maximum intensity tolerance. That is why the therapeutic success of (WB-)EMS may depend on individual anatomical parameters. The aim of the study was to find out whether gender, skinfold thickness and parameters of body composition have an influence on the maximum intensity tolerance in WB-EMS. [Participants and Methods] Fifty-two participants were included in the study. Body composition (body impedance, body fat, fat mass, fat-free mass) and skinfold thicknesses were measured and set into relation to the maximum intensity tolerance. [Results] No relationship between the different anthropometric parameters and the maximum intensity tolerance was detected for both genders. Considering the individual muscle groups, no similarities were found in the results. [Conclusion] Body composition or skinfold thickness do not seem to have any influence on the maximum intensity tolerance in WB-EMS training. For the application in physiotherapy this means that a dosage of the electrical voltage within the scope of a (WB-) EMS application is only possible via the subjective feedback (BORG Scale).
In this paper we present the results of the project “#Datenspende” where during the German election in 2017 more than 4000 people contributed their search results regarding keywords connected to the German election campaign.
Analyzing the donated result lists we prove, that the room for personalization of the search results is very small. Thus the opportunity for the effect mentioned in Eli Pariser’s filter bubble theory to occur in this data is also very small, to a degree that it is negligible. We achieved these results by applying various similarity measures to the result lists that were donated. The first approach using the number of common results as a similarity measure showed that the space for personalization is less than two results out of ten on average when searching for persons and at most four regarding the search for parties. Application of other, more specific measures show that the space is indeed smaller, so that the presence of filter bubbles is not evident.
Moreover this project is also a proof of concept, as it enables society to permanently monitor a search engine’s degree of personalization for any desired search terms. The general design can also be transferred to intermediaries, if appropriate APIs restrict selective access to contents relevant to the study in order to establish a similar degree of trustworthiness.
Wear phenomena in worm gears are dependent on the size of the gears. Whereas larger gears are mainly affected by fatigue wear, abrasive wear is predominant in smaller gears. In this context a simulation model for abrasive wear of worm gears was developed, which is based on an energetic wear equation. This approach associates wear with solid friction energy occurring in the tooth contact. The physically-based wear simulation model includes a tooth contact analysis and tribological calculation to determine the local solid tooth friction and wear. The calculation is iterated with the modified tooth flank geometry of the worn worm wheel, in order to consider the influence of wear on the tooth contact. Experimental results on worm gears are used to determine the wear model parameter and to validate the model. A simulative study for a wide range of worm gear geometries was conducted to investigate the influence of geometry and operating conditions on abrasive wear.
With this article we first like to give a brief review on wavelet thresholding methods in non-Gaussian and non-i.i.d. situations, respectively. Many of these applications are based on Gaussian approximations of the empirical coefficients. For regression and density estimation with independent observations, we establish joint asymptotic normality of the empirical coefficients by means of strong approximations. Then we describe how one can prove asymptotic normality under mixing conditions on the observations by cumulant techniques.; In the second part, we apply these non-linear adaptive shrinking schemes to spectral estimation problems for both a stationary and a non-stationary time series setup. For the latter one, in a model of Dahlhaus on the evolutionary spectrum of a locally stationary time series, we present two different approaches. Moreover, we show that in classes of anisotropic function spaces an appropriately chosen wavelet basis automatically adapts to possibly different degrees of regularity for the different directions. The resulting fully-adaptive spectral estimator attains the rate that is optimal in the idealized Gaussian white noise model up to a logarithmic factor.
We derive minimax rates for estimation in anisotropic smoothness classes. This rate is attained by a coordinatewise thresholded wavelet estimator based on a tensor product basis with separate scale parameter for every dimension. It is shown that this basis is superior to its one-scale multiresolution analog, if different degrees of smoothness in different directions are present.; As an important application we introduce a new adaptive wavelet estimator of the time-dependent spectrum of a locally stationary time series. Using this model which was resently developed by Dahlhaus, we show that the resulting estimator attains nearly the rate, which is optimal in Gaussian white noise, simultaneously over a wide range of smoothness classes. Moreover, by our new approach we overcome the difficulty of how to choose the right amount of smoothing, i.e. how to adapt to the appropriate resolution, for reconstructing the local structure of the evolutionary spectrum in the time-frequency plane.
We consider wavelet estimation of the time-dependent (evolutionary) power spectrum of a locally stationary time series. Allowing for departures from stationary proves useful for modelling, e.g., transient phenomena, quasi-oscillating behaviour or spectrum modulation. In our work wavelets are used to provide an adaptive local smoothing of a short-time periodogram in the time-freqeuncy plane. For this, in contrast to classical nonparametric (linear) approaches we use nonlinear thresholding of the empirical wavelet coefficients of the evolutionary spectrum. We show how these techniques allow for both adaptively reconstructing the local structure in the time-frequency plane and for denoising the resulting estimates. To this end a threshold choice is derived which is motivated by minimax properties w.r.t. the integrated mean squared error. Our approach is based on a 2-d orthogonal wavelet transform modified by using a cardinal Lagrange interpolation function on the finest scale. As an example, we apply our procedure to a time-varying spectrum motivated from mobile radio propagation.
River ecosystems are being threatened by rising temperatures, aridity, and salinity due to climate change and increased water abstractions. These threats also put human well-being at risk, as people and rivers are closely connected, particularly in water-scarce regions. We aimed to investigate the relationship between human well-being and biological and physico-chemical river water quality using the arid Draa River basin as a case study. Physico-chemical water measurements, biological monitoring of aquatic macroinvertebrates, and household surveys were used to assess the state of the river water, ecosystem, and human well-being, as well as the associations between them. Salinity levels exceeded maximum permissible values for drinking water in 35 % and irrigation water in 12 % of the sites. Salinity and low flow were associated with low biological quality. Human satisfaction with water quantity and quality, agriculture, the natural environment, and overall life satisfaction were low particularly in the Middle Draa, where 89% of respondents reported emotional distress due to water salinity and scarcity. Drinking and irrigation water quality was generally rated lower in areas characterized by higher levels of water salinity and scarcity. The study found positive associations between the river water quality and biological quality indices, but no significant association between these factors and human satisfaction. These findings suggest that the relationship between human satisfaction and the biological and physicochemical river water quality is complex and that a more comprehensive approach to human well-being is likely needed to establish relationships.
Water availability shapes edaphic and lithic cyanobacterial communities in the Atacama Desert
(2019)
In the Atacama Desert, cyanobacteria grow on various substrates such as soils (edaphic) and quartz or granitoid stones (lithic). Both edaphic and lithic cyanobacterial communities have been described but no comparison between both communities of the same locality has yet been undertaken. In the present study, we compared both cyanobacterial communities along a precipitation gradient ranging from the arid National Park Pan de Azúcar (PA), which resembles a large fog oasis in the Atacama Desert extending to the semiarid Santa Gracia Natural Reserve (SG) further south, as well as along a precipitation gradient within PA. Various microscopic techniques, as well as culturing and partial 16S rRNA sequencing, were applied to identify 21 cyanobacterial species; the diversity was found to decline as precipitation levels decreased. Additionally, under increasing xeric stress, lithic community species composition showed higher divergence from the surrounding edaphic community, resulting in indigenous hypolithic and chasmoendolithic cyanobacterial communities. We conclude that rain and fog water, respectively, cause contrasting trends regarding cyanobacterial species richness in the edaphic and lithic microhabitats.
A simple method of calculating the Wannier-Stark resonances in 2D lattices is suggested. Using this method we calculate the complex Wannier-Stark spectrum for a non-separable 2D potential realized in optical lattices and analyze its general structure. The dependence of the lifetime of Wannier-Stark states on the direction of the static field (relative to the crystallographic axis of the lattice) is briefly discussed.
The paper studies the effect of a weak periodic driving on metastable Wannier-Stark states. The decay rate of the ground Wannier-Stark states as a continuous function of the driving frequency is calculated numerically. The theoretical results are compared with experimental data of Wilkinson et at. [Phys.Rev.Lett.76, 4512 (1996)] obtained for cold sodium atoms in an accelerated optical lattice.
Wall energy and wall thickness of exchange-coupled rare-earth transition-metal triple layer stacks
(1999)
The room-temperature wall energy sw 54.0310 23 J/m 2 of an exchange-coupled Tb 19.6 Fe 74.7 Co 5.7 /Dy 28.5 Fe 43.2 Co 28.3 double layer stack can be reduced by introducing a soft magnetic intermediate layer in between both layers exhibiting a significantly smaller anisotropy compared to Tb+- FeCo and Dy+- FeCo. sw will decrease linearly with increasing intermediate layer thickness, d IL , until the wall is completely located within the intermediate layer for d IL d w , where d w denotes the wall thickness. Thus, d w can be obtained from the plot sw versus d IL .We determined sw and d w on Gd+- FeCo intermediate layers with different anisotropy behavior ~perpendicular and in-plane easy axis! and compared the results with data obtained from Brillouin light-scattering measurements, where exchange stiffness, A, and uniaxial anisotropy, K u , could be determined. With the knowledge of A and K u , wall energy and thickness were calculated and showed an excellent agreement with the magnetic measurements. A ten times smaller perpendicular anisotropy of Gd 28.1 Fe 71.9 in comparison to Tb+- FeCo and Dy+- FeCo resulted in a much smaller sw 51.1310 23 J/m 2 and d w 524 nm at 300 K. A Gd 34.1 Fe 61.4 Co 4.5 with in-plane anisotropy at room temperature showed a further reduced sw 50.3310 23 J/m 2 and d w 517 nm. The smaller wall energy was a result of a different wall structure compared to perpendicular layers.
The coordination of multiple external representations is important for learning, but yet a difficult task for students, requiring instructional support. The subject in this study covers a typical relation in physics between abstract mathematical equations (definitions of divergence and curl) and a visual representation (vector field plot). To support the connection across both representations, two instructions with written explanations, equations, and visual representations (differing only in the presence of visual cues) were designed and their impact on students’ performance was tested. We captured students’ eye movements while they processed the written instruction and solved subsequent coordination tasks. The results show that students instructed with visual cues (VC students) performed better, responded with higher confidence, experienced less mental effort, and rated the instructional quality better than students instructed without cues. Advanced eye-tracking data analysis methods reveal that cognitive integration processes appear in both groups at the same point in time but they are significantly more pronounced for VC students, reflecting a greater attempt to construct a coherent mental representation during the learning process. Furthermore, visual cues increase the fixation count and total fixation duration on relevant information. During problem solving, the saccadic eye movement pattern of VC students is similar to experts in this domain. The outcomes imply that visual cues can be beneficial in coordination tasks, even for students with high domain knowledge. The study strongly confirms an important multimedia design principle in instruction, that is, that highlighting conceptually relevant information shifts attention to relevant information and thus promotes learning and problem solving. Even more, visual cues can positively influence students’ perception of course materials.
Virtual Robot Programming for Deformable Linear Objects: System concept and Prototype Implementation
(2002)
In this paper we present a method and system for robot programming using virtual reality techniques. The proposed method allows intuitive teaching of a manipulation task with haptic feedback in a graphical simulation system. Based on earlier work, our system allows even an operator who lacks specialized knowledge of robotics to automatically generate a robust sensor-based robot program that is ready to execute on different robots, merely by demonstrating the task in virtual reality.
VIPP proteins aid thylakoid biogenesis and membrane maintenance in cyanobacteria, algae, and plants. Some members of the Chlorophyceae contain two VIPP paralogs termed VIPP1 and VIPP2, which originate from an early gene duplication event during the evolution of green algae. VIPP2 is barely expressed under nonstress conditions but accumulates in cells exposed to high light intensities or H2O2, during recovery from heat stress, and in mutants with defective integration (alb3.1) or translocation (secA) of thylakoid membrane proteins. Recombinant VIPP2 forms rod-like structures in vitro and shows a strong affinity for phosphatidylinositol phosphate. Under stress conditions, >70% of VIPP2 is present in membrane fractions and localizes to chloroplast membranes. A vipp2 knock-out mutant displays no growth phenotypes and no defects in the biogenesis or repair of photosystem II. However, after exposure to high light intensities, the vipp2 mutant accumulates less HSP22E/F and more LHCSR3 protein and transcript. This suggests that VIPP2 modulates a retrograde signal for the expression of nuclear genes HSP22E/F and LHCSR3. Immunoprecipitation of VIPP2 from solubilized cells and membrane-enriched fractions revealed major interactions with VIPP1 and minor interactions with HSP22E/F. Our data support a distinct role of VIPP2 in sensing and coping with chloroplast membrane stress.
In cyanobacteria and plants, VIPP1 plays crucial roles in the biogenesis and repair of thylakoid membrane protein complexes and in coping with chloroplast membrane stress. In chloroplasts, VIPP1 localizes in distinct patterns at or close to envelope and thylakoid membranes. In vitro, VIPP1 forms higher-order oligomers of >1 MDa that organize into rings and rods. However, it remains unknown how VIPP1 oligomerization is related to function. Using time-resolved fluorescence anisotropy and sucrose density gradient centrifugation, we show here that Chlamydomonas reinhardtii VIPP1 binds strongly to liposomal membranes containing phosphatidylinositol-4-phosphate (PI4P). Cryo-electron tomography reveals that VIPP1 oligomerizes into rods that can engulf liposomal membranes containing PI4P. These findings place VIPP1 into a group of membrane-shaping proteins including epsin and BAR domain proteins. Moreover, they point to a potential role of phosphatidylinositols in directing the shaping of chloroplast membranes.
Within this work, we report the results of nuclear inelastic scattering experiments of the low-spin phase of the iron(II) mononuclear SCO complex Fe[HBpz3]2 and density functional theory based calculations performed on a model molecule of the complex. We show that the calculated partial density of vibrational states based on the structure of a single iron(II) center which is linked by three pyrazole rings to borat is in good accordance with the experimentally obtained 57Fe-pDOS and assign the molecular vibrations to the prominent optical phonons.
Defects change the phonon spectrum and also the magnetic properties of bcc-Fe. Using molecular dynamics simulation, the influence of defects – vacancies, dislocations, and grain boundaries – on the phonon spectra and magnetic properties of bcc-Fe is determined. It is found that the main influence of defects consists in a decrease of the amplitude of the longitudinal peak, PL, at around 37 meV. While the change in phonon spectra shows only little dependence on the defect type, the quantitative decrease of PL is proportional to the defect concentration. Local magnetic moments can be determined from the local atomic volumes. Again, the changes in the magnetic moments of a defective crystal are linear in the defect concentrations. In addition, the change of the phonon density of states and the magnetic moments under homogeneous uniaxial strain are investigated.
In diesem Papier beschreiben wir eine Methode zur Spezifikation und Operationalisierung von konzeptuellen Modellen kooperativer wissensbasierter Arbeitsabläufe. Diese erweitert bekannte Ansätze um den Begriff des Agenten und um alternative Aufgabenzerlegungen. Das Papier beschreibt schwerpunktmäßig Techniken, die unserem verteilten Interpreter zugrunde liegen. Dabei gehen wir insbesondere auf Methoden ein, die Abhängigkeiten zwischen Aufgaben behandeln und ein zielgerichtetes Backtracking effizient unterstützen.
3D joint kinematics can provide important information about the quality of movements. Optical motion capture systems (OMC) are considered the gold standard in motion analysis. However, in recent years, inertial measurement units (IMU) have become a promising alternative. The aim of this study was to validate IMU-based 3D joint kinematics of the lower extremities during different movements. Twenty-eight healthy subjects participated in this study. They performed bilateral squats (SQ), single-leg squats (SLS) and countermovement jumps (CMJ). The IMU kinematics was calculated using a recently-described sensor-fusion algorithm. A marker based OMC system served as a reference. Only the technical error based on algorithm performance was considered, incorporating OMC data for the calibration, initialization, and a biomechanical model. To evaluate the validity of IMU-based 3D joint kinematics, root mean squared error (RMSE), range of motion error (ROME), Bland-Altman (BA) analysis as well as the coefficient of multiple correlation (CMC) were calculated. The evaluation was twofold. First, the IMU data was compared to OMC data based on marker clusters; and, second based on skin markers attached to anatomical landmarks. The first evaluation revealed means for RMSE and ROME for all joints and tasks below 3°. The more dynamic task, CMJ, revealed error measures approximately 1° higher than the remaining tasks. Mean CMC values ranged from 0.77 to 1 over all joint angles and all tasks. The second evaluation showed an increase in the RMSE of 2.28°– 2.58° on average for all joints and tasks. Hip flexion revealed the highest average RMSE in all tasks (4.87°– 8.27°). The present study revealed a valid IMU-based approach for the measurement of 3D joint kinematics in functional movements of varying demands. The high validity of the results encourages further development and the extension of the present approach into clinical settings.
In diesem Papier stellen wir einen Interpreter vor, der die Validierung von konzeptuellen Modellen bereits in fruehen Entwicklungsphasen unterstuetzt. Wir vergleichen Hypermedia- und Expertensystemansaetze zur Wissensverarbeitung und erlaeutern, wie ein integrierter Ansatz die Erstellung von Expertensystemen vereinfacht. Das von uns entwickelte Knowledge Engineering Werkzeug ermoeglicht einen "sanften" Uebergang von initialen Protokollen ueber eine semi-formale Spezifikation in Form eines getypten Hypertextes hin zu einem operationalen Expertensystem. Ein Interpreter nutzt die in diesem Prozess erzeugte Zwischenrepraesentation direkt zur interaktiven Loesung von Problemen, wobei einzelne Aufgaben ueber ein lokales Rechnernetz auf die Bearbeiter verteilt werden. Das heisst, die Spezifikation des Expertensystems wird direkt fuer die Loesung realer Probleme eingesetzt. Existieren zu einzelnen Teilaufgaben Operationalisierungen (d.h. Programme), dann werden diese vom Computer bearbeitet.
Mobile devices (smartphones or tablets) as experimental tools (METs) offer inspiring possibilities for science education, but until now, there has been little research studying this approach. Previous research indicated that METs have positive effects on students’ interest and curiosity. The present investigation focuses on potential cognitive effects of METs using video analyses on tablets to investigate pendulum movements and an instruction that has been used before to study effects of smartphones’ acceleration sensors. In a quasi-experimental repeated-measurement design, a treatment group uses METs (TG, NTG = 23) and a control group works with traditional experimental tools (CG, NCG = 28) to study the effects on interest, curiosity, and learning achievement. Moreover, various control variables were taken into account. We suppose that pupils in the TG have a lower extraneous cognitive load and higher learning achievement than those in the CG working with traditional experimental tools. ANCOVAs showed significantly higher levels of learning achievement in the TG (medium effect size). No differences were found for interest, curiosity, or cognitive load. This might be due to a smaller material context provided by tablets, in comparison to smartphones, as more pupils possess and are familiar with smartphones than with tablets. Another reason for the unchanged interest might be the composition of the sample: While previous research showed that especially originally less-interested students profited most from using METs, the current sample contained only specialized courses, i.e., students with a high original interest, for whom the effect of METs on their interest is presumably smaller.
We present new results on standard basis computations of a 0-dimensional ideal I in a power series ring or in the localization of a polynomial ring over a computable field K. We prove the semicontinuity of the “highest corner” in a family of ideals, parametrized by the spectrum of a Noetherian domain A. This semicontinuity is used to design a new modular algorithm for computing a standard basis of I if K is the quotient field of A. It uses the computation over the residue field of a “good” prime ideal of A to truncate high order terms in the subsequent computation over K. We prove that almost all prime ideals are good, so a random choice is very likely to be good, and whether it is good is detected a posteriori by the algorithm. The algorithm yields a significant speed advantage over the non-modular version and works for arbitrary Noetherian domains. The most important special cases are perhaps A = ℤ and A = k[t], k any field and t a set of parameters. Besides its generality, the method differs substantially from previously known modular algorithms for A = ℤ, since it does not manipulate the coefficients. It is also usually faster and can be combined with other modular methods for computations in local rings. The algorithm is implemented in the computer algebra system SINGULAR and we present several examples illustrating its power.
Typical instances, that is, instances that are representative for a particular situ-ation or concept, play an important role in human knowledge representationand reasoning, in particular in analogical reasoning. This wellADknown obser-vation has been a motivation for investigations in cognitive psychology whichprovide a basis for our characterization of typical instances within conceptstructures and for a new inference rule for justified analogical reasoning withtypical instances. In a nutshell this paper suggests to augment the proposi-tional knowledge representation system by a non-propositional part consistingof concept structures which may have directly represented instances as ele-ments. The traditional reasoning system is extended by a rule for justifiedanalogical inference with typical instances using information extracted fromboth knowledge representation subsystems.
Erstmalig wurde Synchrotron-basierte nukleare inelastische Streuung (NIS) unter Nutzung des Mößbauer-Isotops 161Dy für die Untersuchung der vibronischen Eigenschaften eines DyIII-basierten Einzelmolekülmagneten, [Dy(Cy3PO)2(H2O)5]Br3⋅2 (Cy3PO)⋅2 H2O⋅2 EtOH, eingesetzt. Die experimentelle partielle Phononen-Zustandsdichte, die alle Schwingungen mit einer Auslenkung des DyIII-Ions enthält, wurde mit Hilfe von auf Dichtefunktionaltheorie (DFT) basierenden Simulationen reproduziert, was die Zuordnung aller intramolekularen Schwingungsmoden des Moleküls ermöglicht. Diese Studie zeigt, dass 161Dy-NIS als eine experimentelle Methode ein hohes Potential besitzt, um zur Klärung der Rolle von Phononen in Einzelmolekülmagneten beizutragen.
Nanostructured tantalum (Ta)-based dental implants have recently attracted significant attention thanks to their superior biocompatibility and bioactivity as compared to their titanium-based counterparts. While the biological and chemical aspects of Ta implants have been widely studied, their mechanical features have been investigated more rarely. Additionally, the mechanical behavior of these implants and, more importantly, their plastic deformation mechanisms are still not fully understood. Accordingly, in the current research, molecular dynamics simulation as a powerful tool for probing the atomic-scale phenomena is utilized to explore the microstructural evolution of pure polycrystalline Ta samples under tensile loading conditions. Various samples with an average grain size of 2–10 nm are systematically examined using various crystal structure analysis tools to determine the underlying deformation mechanisms. The results reveal that for the samples with an average grain size larger than 8 nm, twinning and dislocation slip are the main sources of any plasticity induced within the sample. For finer-grained samples, the activity of grain boundaries—including grain elongation, rotation, migration, and sliding—are the most important mechanisms governing the plastic deformation. Finally, the temperature-dependent Hall–Petch breakdown is thoroughly examined for the nanocrystalline samples via identification of the grain boundary dynamics.
Iterative methods to solve linear equation systems are widely used in computational physics, engineering and many areas of applied mathematics. In recent works, performance improvements have been achieved based on modifications of several classes of iterative algorithms by various research communities driven by different perspectives and applications. This note presents a brief analysis of conventional and unifying perspectives by highlighting relations between several well-known iterative methods to solve linear equation systems and explicit Euler approximations of the associated parabolic regularized equations. Special cases of equivalence and general relations between different iterative methods such as Jacobi iterations, Richardson iterations, Steepest Descent and Quasi-Newton methods are shown and discussed. The results and discussion extend the conventional perspectives on these iterative methods and give way to intuitive physical interpretations and analogies. The accessibly presented relations give complementary educational insights and aim to inspire transdisciplinary developments of new iterative methods, solvers and preconditioners.
Unification in an Extensional Lambda Calculus with Ordered Function Sorts and Constant Overloading
(1999)
We develop an order-sorted higher-order calculus suitable forautomatic theorem proving applications by extending the extensional simplytyped lambda calculus with a higher-order ordered sort concept and constantoverloading. Huet's well-known techniques for unifying simply typed lambdaterms are generalized to arrive at a complete transformation-based unificationalgorithm for this sorted calculus. Consideration of an order-sorted logicwith functional base sorts and arbitrary term declarations was originallyproposed by the second author in a 1991 paper; we give here a correctedcalculus which supports constant rather than arbitrary term declarations, aswell as a corrected unification algorithm, and prove in this setting resultscorresponding to those claimed there.
The introduction of sorts to first-order automated deduc-tion has brought greater conciseness of representation and a considerablegain in efficiency by reducing search spaces. This suggests that sort in-formation can be employed in higher-order theorem proving with similarresults. This paper develops a sorted (lambda)-calculus suitable for automatictheorem proving applications. It extends the simply typed (lambda)-calculus by ahigher-order sort concept that includes term declarations and functionalbase sorts. The term declaration mechanism studied here is powerfulenough to subsume subsorting as a derived notion and therefore gives ajustification for the special form of subsort inference. We present a set oftransformations for sorted (pre-) unification and prove the nondetermin-istic completeness of the algorithm induced by these transformations.
Arctic, Antarctic and alpine biological soil crusts (BSCs) are formed by adhesion of soil particles to exopolysaccharides (EPSs) excreted by cyanobacterial and green algal communities, the pioneers and main primary producers in these habitats. These BSCs provide and influence many ecosystem services such as soil erodibility, soil formation and nitrogen (N) and carbon (C) cycles. In cold environments degradation rates are low and BSCs continuously increase soil organic C; therefore, these soils are considered to be CO2 sinks. This work provides a novel, nondestructive and highly comparable method to investigate intact BSCs with a focus on cyanobacteria and green algae and their contribution to soil organic C. A new terminology arose,basedonconfocallaserscanningmicroscopy(CLSM) 2-D biomaps, dividing BSCs into a photosynthetic active layer (PAL) made of active photoautotrophic organisms and a photosynthetic inactive layer (PIL) harbouring remnants of cyanobacteria and green algae glued together by their remaining EPSs. By the application of CLSM image analysis (CLSM–IA) to 3-D biomaps, C coming from photosynthetic activeorganismscouldbevisualizedasdepthprofileswithC peaks at 0.5 to 2mm depth. Additionally, the CO2 sink character of these cold soil habitats dominated by BSCs could be highlighted, demonstrating that the first cubic centimetre of soil consists of between 7 and 17% total organic carbon, identified by loss on ignition.
In many applications, visual analytics (VA) has developed into a standard tool to ease data access and knowledge generation. VA describes a holistic cycle transforming data into hypothesis and visualization to generate insights that enhance the data. Unfortunately, many data sources used in the VA process are affected by uncertainty. In addition, the VA cycle itself can introduce uncertainty to the knowledge generation process but does not provide a mechanism to handle these sources of uncertainty. In this manuscript, we aim to provide an extended VA cycle that is capable of handling uncertainty by quantification, propagation, and visualization, defined as uncertainty-aware visual analytics (UAVA). Here, a recap of uncertainty definition and description is used as a starting point to insert novel components in the visual analytics cycle. These components assist in capturing uncertainty throughout the VA cycle. Further, different data types, hypothesis generation approaches, and uncertainty-aware visualization approaches are discussed that fit in the defined UAVA cycle. In addition, application scenarios that can be handled by such a cycle, examples, and a list of open challenges in the area of UAVA are provided.
Algorithms are increasingly used in different domains of public policy. They help humans to profile unemployed, support administrations to detect tax fraud and give recidivism risk scores that judges or criminal justice managers take into account when they make bail decisions. In recent years, critics have increasingly pointed to ethical challenges of these tools and emphasized problems of discrimination, opaqueness or accountability, and computer scientists have proposed technical solutions to these issues. In contrast to these important debates, the literature on how these tools are implemented in the actual everyday decision-making process has remained cursory. This is problematic because the consequences of ADM systems are at least as dependent on the implementation in an actual decision-making context as on their technical features. In this study, we show how the introduction of risk assessment tools in the criminal justice sector on the local level in the USA has deeply transformed the decision-making process. We argue that this is mainly due to the fact that the evidence generated by the algorithm introduces a notion of statistical prediction to a situation which was dominated by fundamental uncertainty about the outcome before. While this expectation is supported by the case study evidence, the possibility to shift blame to the algorithm does seem much less important to the criminal justice actors.
Von den Umweltberichten deutscher Unternehmen werden bisher erst unter 3% im Internet veröffentlicht. Die Tendenz ist steigend. Hier werden die im Internet verfügbaren Umweltberichte ausgewertet und Gründe für die Nutzung des Internet für die Umweltberichterstattung vorgetragen. Der Beitrag ist in fünf Abschnitte gegliedert: Zur thematischen Einführung werden betriebliche Umweltberichte durch eine Morphologie charakterisiert (Abschnitt 2). Es schließen sich die IKT-spezifischen Herausforderungen an umweltberichterstattende Unternehmen als Ansatzpunkte für Umweltberichte im Internet an (Abschnitt 3). Damit ist die Basis für eine Systematisierung der internetbasierten Unterstützungspotenziale zur Umweltberichterstattung gelegt (Abschnitt 4). Der Systematik folgt eine detaillierte Bestandsaufnahme der Umweltberichte deutscher Unternehmen im Internet in fünffacher Hinsicht (Abschnitt 5): Die zugrunde gelegte Untersuchungsmethodik zur Bestandsaufnahme wird erläutert (Abschnitt 5.1). Die ergänzend herangezogenen empirischen Studien zu Umweltberichten im Internet werden ausgewertet (Abschnitt 5.2). Die Ergebnisse bzgl. Inhalt und Darstellung von Umweltberichten im Internet werden ausführlicher beschrieben (Abschnitt 5.3) und durch Erklärungsansätze interpretiert (Abschnitt 5.4). Abschließend werden auf der Grundlage der konzeptionell erschließbaren Unterstützungspotenziale einerseits und der empirischen Studien andererseits zentrale Tendenzen zur zukünftigen Entwicklung von Umweltberichten im Internet vorgetragen (Abschnitt 5.5).
Hier werden die im Internet verfügbaren Umweltberichte von Unternehmen ausgewertet, Praxiserfahrungen von im Internet umweltberichterstattenden Unternehmen dokumentiert, generelle Gründe für die Nutzung des Internet für die Umweltberichterstattung vorgetragen, eine Klassifikation von Umweltberichten im Internet entworfen und Entwicklungstendenzen in der Umweltberichterstattung skizziert. Die Studie ist in sechs Kapitel gegliedert: Zur thematischen Einführung werden Umweltberichte als Kern der Umweltkommunikation von Unternehmen behandelt (Kapitel 2). Es schließen sich die spezifischen informations- und kommunikationstechnischen (IKT) Herausforderungen an umweltberichterstattende Unternehmen an. Diese werden als Ansatzpunkte für eine Umweltberichterstattung im Internet sowie zur Ausschöpfung der technischen Unterstützungspotentiale des Internet betrachtet (Kapitel 3). Damit ist die Basis für eine Übersicht über die verschiedenen technischen Unterstützungspotentiale beim Einsatz von Internettechnologien und -diensten für die Umweltberichterstattung gelegt (Kapitel 4). Der Übersicht folgt eine detaillierte Bestandsaufnahme zu Umweltberichten von Unternehmen im Internet für Deutschland (Kapitel 5). Auf der Grundlage der Bestandsaufnahme wird abschließend für den Einsatz des Internet zur Umweltberichterstattung argumentiert (Kapitel 6).
Die Umweltberichterstattung spielt sowohl für den ökonomischen Erfolg von Unternehmen als auch für eine ökologisch nachhaltige Entwicklung eine zunehmend wichtige Rolle. Dafür sprechen drei Gründe: Erstens können Unternehmen kön-nen durch eine freiwillige und informative Umweltberichterstattung ökologische Schwachstellen aufdecken, Umweltbelastungen reduzieren und Wettbewerbsvorteile im Markt erzielen. Zweitens nehmen gesetzliche und moralische Verpflichtungen zur Umweltberichterstattung zu. Drittens sind die technischen Möglichkeiten zur Umweltberichterstattung durch den Einsatz des Internet enorm gestiegen. Alle drei Tendenzen sind gute Gründe für den Einsatz des Internet zur Umweltberichterstattung. Allerdings sind bei den Umweltberichten von kleinen und mittelständischen Unternehmen (KMU) insgesamt bisher erst weniger als 3% im Internet veröffentlicht, die Tendenz ist jedoch steigend. Bislang nutzen überwiegend internationale und weltweit tätige Großunternehmen das Internet zur Umweltberichterstattung. KMU präsentieren bislang nur selten Umweltberichte im Internet. Hier werden die im Internet verfügbaren Umweltberichte von KMU ausgewertet, generelle Gründe für die Nutzung des Internet für die Umweltberichterstattung vorgetragen und die Möglichkeiten von KMU für eine internetbasierte Umweltbe-richterstattung am Beispiel von Umweltberichten dargestellt. Die Studie ist in sechs Kapitel gegliedert: Zur thematischen Einführung werden Umweltberichte als Kern der Umweltkommunikation von Unternehmen behandelt (Kapitel 2). Es schließen sich die informations- und kommunikationstechnischen (IKT) Herausforderungen an umweltberichterstattende Unternehmen an. Sie werden als Ansatzpunkte für Umweltberichte im Internet und zur Ausschöpfung der technischen Unterstützungspotentiale des Internet betrachtet (Kapitel 3). Damit ist die Basis für eine Übersicht über die verschiedenen technischen Unterstützungspotentiale beim Einsatz von Internettechnologien und -diensten für die Umweltbe-richterstattung gelegt (Kapitel 4). Der Übersicht folgt eine detaillierte Bestandsauf-nahme von Umweltberichten im Internet von KMU in Deutschland (Kapitel 5). Auf der Grundlage der empirischen Bestandsaufnahme werden dann die Möglichkeiten einer internetbasierten Umweltberichterstattung für KMU abgeleitet (Kapitel 6).
Deactivation processes of photoexcited (λex = 580 nm) phycocyanobilin (PCB) in methanol were investigated by means of UV/Vis and mid-IR femtosecond (fs) transient absorption (TA) as well as static fluorescence spectroscopy, supported by density-functional-theory calculations of three relevant ground state conformers, PCBA, PCBB and PCBC, their relative electronic state energies and normal mode vibrational analysis. UV/Vis fs-TA reveals time constants of 2.0, 18 and 67 ps, describing decay of PCBB*, of PCBA* and thermal re-equilibration of PCBA, PCBB and PCBC, respectively, in line with the model by Dietzek et al. (Chem Phys Lett 515:163, 2011) and predecessors. Significant substantiation and extension of this model is achieved first via mid-IR fs-TA, i.e. identification of molecular structures and their dynamics, with time constants of 2.6, 21 and 40 ps, respectively. Second, transient IR continuum absorption (CA) is observed in the region above 1755 cm−1 (CA1) and between 1550 and 1450 cm−1 (CA2), indicative for the IR absorption of highly polarizable protons in hydrogen bonding networks (X–H…Y). This allows to characterize chromophore protonation/deprotonation processes, associated with the electronic and structural dynamics, on a molecular level. The PCB photocycle is suggested to be closed via a long living (> 1 ns), PCBC-like (i.e. deprotonated), fluorescent species.
The Griffith-Ley oxidation of alcohols to aldehydes and ketones is performed with either RuCl3 ⋅ (H2O)x or a highly stable, well-defined ruthenium catalyst and with cheap trimethylamine N-oxide (TMAO) as the oxygen source. The use of n-heptane as the solvent, which forms a second phase with TMAO and a part of the alcohol, allows the reactions to be performed with a minimum amount of catalyst. This results in high local concentrations and thus to very rapid conversions. Detailed quantum chemical calculations suggest, that the Griffith-Ley oxidation not necessarily requires high oxidation states of ruthenium but can also proceed with RuII/RuIV species.
The following two norms for holomorphic functions \(F\), defined on the right complex half-plane \(\{z \in C:\Re(z)\gt 0\}\) with values in a Banach space \(X\), are equivalent:
\[\begin{eqnarray*} \lVert F \rVert _{H_p(C_+)} &=& \sup_{a\gt0}\left( \int_{-\infty}^\infty \lVert F(a+ib) \rVert ^p \ db \right)^{1/p}
\mbox{, and} \\ \lVert F \rVert_{H_p(\Sigma_{\pi/2})} &=& \sup_{\lvert \theta \lvert \lt \pi/2}\left( \int_0^\infty \left \lVert F(re^{i \theta}) \right \rVert ^p\ dr \right)^{1/p}.\end{eqnarray*}\] As a consequence, we derive a description of boundary values ofsectorial holomorphic functions, and a theorem of Paley-Wiener typefor sectorial holomorphic functions.
Passive graduated filters with fixed absorption profile are currently used in image recording to avoid overexposure. However, a whole set of filters with prescribed gradients is required to cope with changing illumination conditions. Furthermore, they demand mechanical adjustment during operation. To overcome these deficiencies we present a microfabricated active electrochromic graduated filter which combines multiple functionalities: The overall absorbance, the position of medium transmission as well as the magnitude of its gradient can be tuned continuously by electrical means. Live image control is possible using low operation voltages in the range of ±2 V to reach a high change in optical density ΔOD of 1.01 (400 nm to 780 nm) with a coloration and bleaching time 1.3 s and 0.2 s, respectively. Owing to their low volume and power consumption they are suitable for widespread applications like in smartphones, surveillance cameras or microscopes.
Spatial optical Fourier filtering is a widespread technique for in situ image or light
field processing. However, conventional fixed absorbing patterns or mechanical irises only allow
an inflexible, very restricted control. Thus, we present two electrochromic spatial filters with
ring-shaped or directional segments, which can be individually addressed and continuously tuned
in transmission resulting in up to 512 different filtering states. For realization of the electrochromic
devices, we overcome technical obstacles to realize seamless, gap-free electrochromic segments.
We describe this novel fabrication process and demonstrate the successful application in an
optical Fourier transform set-up.
Existentialist philosophy offers an understanding of how trying to eliminate ambiguities that inevitably mark the human condition only seemingly leads to freedom. This existentialist outlook can also serve to shed light on how democratic politics may similarly show tendencies which aim at overcoming immanent tensions. Such tendencies in democratic politics can be clarified using Sartre’s notion of ignorance – and truth as its counterpart. His concept of ignorance goes beyond merely facts or knowledge and refers to a mode of being. It expresses a subject’s desire to avoid, rather than confront, resistances stemming from the world. Based on a distinction of different forms in which this orientation can manifest itself, this article shows how democratic politics, too, can be threatened by ignorance as a way of doing politics. This ignorance comes in different guises which all express a desire to eliminate tensions that democratic politics cannot overcome without undermining itself.
Most automated theorem provers suffer from the problemthat the resulting proofs are difficult to understand even for experiencedmathematicians. An effective communication between the system andits users, however, is crucial for many applications, such as in a mathematical assistant system. Therefore, efforts have been made to transformmachine generated proofs (e.g. resolution proofs) into natural deduction(ND) proofs. The state-of-the-art procedure of proof transformation fol-lows basically its completeness proof: the premises and the conclusionare decomposed into unit literals, then the theorem is derived by mul-tiple levels of proofs by contradiction. Indeterminism is introduced byheuristics that aim at the production of more elegant results. This inde-terministic character entails not only a complex search, but also leads tounpredictable results.In this paper we first study resolution proofs in terms of meaningful op-erations employed by human mathematicians, and thereby establish acorrespondence between resolution proofs and ND proofs at a more ab-stract level. Concretely, we show that if its unit initial clauses are CNFsof literal premises of a problem, a unit resolution corresponds directly toa well-structured ND proof segment that mathematicians intuitively un-derstand as the application of a definition or a theorem. The consequenceis twofold: First it enhances our intuitive understanding of resolutionproofs in terms of the vocabulary with which mathematicians talk aboutproofs. Second, the transformation process is now largely deterministicand therefore efficient. This determinism also guarantees the quality ofresulting proofs.
Cutting of metallic glasses produces as a rule serrated and segmented chips in experiments, while atomistic simulations produce straight unserrated chips. We demonstrate here that with increasing depth of cut – with all other parameters unchanged – chip serration starts to affect the morphology of the chip also in molecular dynamics simulations. The underlying reason is the shear localization in shear bands. As the distance between shear bands increases with increasing depth of cut, the surface morphology of the chip becomes increasingly segmented. The parallel shear bands that formed during cutting do no longer interact with each other when their separation is ≳10 nm. Our results are analogous to the so-called fold instability that has been found when machining nanocrystalline metals.
Over the past 2 decades, there has been much progress on the classification of symplectic linear quotient singularities V/G admitting a symplectic (equivalently, crepant) resolution of singularities. The classification is almost complete but there is an infinite series of groups in dimension 4—the symplectically primitive but complex imprimitive groups—and 10 exceptional groups up to dimension 10, for which it is still open. In this paper, we treat the remaining infinite series and prove that for all but possibly 39 cases there is no symplectic resolution. We thereby reduce the classification problem to finitely many open cases. We furthermore prove non-existence of a symplectic resolution for one exceptional group, leaving 39+9=48 open cases in total. We do not expect any of the remaining cases to admit a symplectic resolution.
Introducing parallelism and exploring its use is still a fundamental challenge for the computer algebra community. In high-performance numerical simulation, on the other hand, transparent environments for distributed computing which follow the principle of separating coordination and computation have been a success story for many years. In this paper, we explore the potential of using this principle in the context of computer algebra. More precisely, we combine two well-established systems: The mathematics we are interested in is implemented in the computer algebra system SINGULAR, whose focus is on polynomial computations, while the coordination is left to the workflow management system GPI-Space, which relies on Petri nets as its mathematical modeling language and has been successfully used for coordinating the parallel execution (autoparallelization) of academic codes as well as for commercial software in application areas such as seismic data processing. The result of our efforts is a major step towards a framework for massively parallel computations in the application areas of SINGULAR, specifically in commutative algebra and algebraic geometry. As a first test case for this framework, we have modeled and implemented a hybrid smoothness test for algebraic varieties which combines ideas from Hironaka’s celebrated desingularization proof with the classical Jacobian criterion. Applying our implementation to two examples originating from current research in algebraic geometry, one of which cannot be handled by other means, we illustrate the behavior of the smoothness test within our framework and investigate how the computations scale up to 256 cores.
Patients after total hip arthroplasty (THA) suffer from lingering musculoskeletal restrictions. Three-dimensional (3D) gait analysis in combination with machine-learning approaches is used to detect these impairments. In this work, features from the 3D gait kinematics, spatio temporal parameters (Set 1) and joint angles (Set 2), of an inertial sensor (IMU) system are proposed as an input for a support vector machine (SVM) model, to differentiate impaired and non-impaired gait. The features were divided into two subsets. The IMU-based features were validated against an optical motion capture (OMC) system by means of 20 patients after THA and a healthy control group of 24 subjects. Then the SVM model was trained on both subsets. The validation of the IMU system-based kinematic features revealed root mean squared errors in the joint kinematics from 0.24° to 1.25°. The validity of the spatio-temporal gait parameters (STP) revealed a similarly high accuracy. The SVM models based on IMU data showed an accuracy of 87.2% (Set 1) and 97.0% (Set 2). The current work presents valid IMU-based features, employed in an SVM model for the classification of the gait of patients after THA and a healthy control. The study reveals that the features of Set 2 are more significant concerning the classification problem. The present IMU system proves its potential to provide accurate features for the incorporation in a mobile gait-feedback system for patients after THA.
Background: The use of health apps to support the treatment of chronic pain is gaining importance. Most available pain management apps are still lacking in content quality and quantity as their developers neither involve health experts to ensure target group suitability nor use gamification to engage and motivate the user. To close this gap, we aimed to develop a gamified pain management app, Pain-Mentor.
Objective: To determine whether medical professionals would approve of Pain-Mentor’s concept and content, this study aimed to evaluate the quality of the app’s first prototype with experts from the field of chronic pain management and to discover necessary improvements.
Methods: A total of 11 health professionals with a background in chronic pain treatment and 2 mobile health experts participated in this study. Each expert first received a detailed presentation of the app. Afterward, they tested Pain-Mentor and then rated its quality using the mobile application rating scale (MARS) in a semistructured interview.
Results: The experts found the app to be of excellent general (mean 4.54, SD 0.55) and subjective quality (mean 4.57, SD 0.43). The app-specific section was rated as good (mean 4.38, SD 0.75). Overall, the experts approved of the app’s content, namely, pain and stress management techniques, behavior change techniques, and gamification. They believed that the use of gamification in Pain-Mentor positively influences the patients’ motivation and engagement and thus has the potential to promote the learning of pain management techniques. Moreover, applying the MARS in a semistructured interview provided in-depth insight into the ratings and concrete suggestions for improvement.
Conclusions: The experts rated Pain-Mentor to be of excellent quality. It can be concluded that experts perceived the use of gamification in this pain management app in a positive manner. This showed that combining pain management with gamification did not negatively affect the app’s integrity. This study was therefore a promising first step in the development of Pain-Mentor.
In recent years, the concept of a centralized drainage system that connect an entire city to one single treatment plant is increasingly being questioned in terms of the costs, reliability, and environmental impacts. This study introduces an optimization approach based on decentralization in order to develop a cost-effective and sustainable sewage collection system. For this purpose, a new algorithm based on the growing spanning tree algorithm is developed for decentralized layout generation and treatment plant allocation. The trade-off between construction and operation costs, resilience, and the degree of centralization is a multiobjective problem that consists of two subproblems: the layout of the networks and the hydraulic design. The innovative characteristics of the proposed framework are that layout and hydraulic designs are solved simultaneously, three objectives are optimized together, and the entire problem solving process is self-adaptive. The model is then applied to a real case study. The results show that finding an optimum degree of centralization could reduce not only the network’s costs by 17.3%, but could also increase its structural resilience significantly compared to fully centralized networks.
Using an experience factory is one possible concept for supporting and improving reuse in software development. (i.e., reuse of products, processes, quality models, ...). In the context of the Sonderforschungsbereich 501: "Development of Large Systems with Generic methods" (SFB501), the Software Engineering Laboratory (SE Lab) runs such an experience factory as part of the infrastructure services it offers. The SE Lab also provides several tools to support the planning, developing, measuring, and analyzing activities of software development processes. Among these tools, the SE Lab runs and maintains an experience base, the SFB-EB. When an experience factory is utilized, support for experience base maintenance is an important issue. Furthermore, it might be interesting to evaluate experience base usage with regard to the number of accesses to certain experience elements stored in the database. The same holds for the usage of the tools provided by the SE LAB. This report presents a set of supporting tools that were designed to aid in these tasks. These supporting tools check the experience base's consistency and gather information on the usage of SFB-EB and the tools installed in the SE Lab. The results are processed periodically and displayed as HTML result reports (consistency checking) or bar charts (usage profiles).
Cell division and cell elongation are fundamental processes for growth. In contrast to animal cells, plant cells are surrounded by rigid walls and therefore loosening of the wall is required during elongation. On the other hand, vacuole size has been shown to correlate with cell size and inhibition of vacuolar expansion limits cell growth. However, the specific role of the vacuole during cell elongation is still not fully resolved. Especially the question whether the vacuole is the leading unit during cellular growth or just passively expands upon water uptake remains to be answered. Here, we review recent findings about the contribution of the vacuole to cell elongation. In addition, we also discuss the connection between cell wall status and vacuolar morphology. In particular, we focus on the question whether vacuolar size is dictated by cell size or vice versa and share our personnel view about the sequential steps during cell elongation.
Opposition parties under minority governments find themselves in a fundamental dilemma. They are competing with other parties, including the government, for electoral support while also having a common responsibility to make stable government work. This dilemma is especially pronounced for opposition parties signing support agreements with the government. While not formally in a coalition, they nonetheless publicly commit to supporting a government. They may thus be concerned about losing distinctiveness and have an interest in strategically timing cooperation with the minority government. The present paper tests whether this is the case using data on opposition party voting on committee proposals from 23 years of Swedish minority governments between 1991 and 2018. The findings indicate that support parties are less likely to support the government towards the beginning and end of the election cycle, that is, when public attention is intense – a pattern that is not observable for other opposition parties.
With direct laser writing micro structures can be manufactured by solidifying a photo resist when the laser beam triggers a photochemical reaction in the focal voxel. We have used direct laser writing to fabricate a thermally actuated microgripper, which can move its two cantilever like arms to grip micro-objects. One cantilever consists thereby of two strips with different coefficients of thermal expansion such that both cantilevers bends towards each other for an increasing temperature like a welded bimetal.This work investigates the impact of each cantilever's geometry on the gripping performance of the micro gripper theoretically. The tip deflection of the gripper is calculated by the analytical model of Timoshenko's theory of elasticity. After fabricaiton of the microgripper, its gripping performance is observed under the microscope while heated by a heating element.
Municipal wastewater is an interesting source of phosphorus and several processes for the recovery of phosphorus from this source have been described. These processes yield magnesium ammonium phosphate (MAP), a valuable fertilizer. In these processes, pH shifts and the addition of chemicals are used to influence the species distribution in the solution such as to finally obtain the desired product and to prevent the co-precipitation of salts of heavy metal ions. Elucidating these species distributions experimentally is a challenging and cumbersome task. Therefore, in the present work, a thermodynamic model was developed that can be used for predicting the species distributions in the various steps of the recovery process. The model combines the extended Debye-Hückel equation for the prediction of activity coefficients with dissociation constants and solubility product data from the literature and contains no parameters that need to be adjusted to process data. The model was successfully tested by comparison to experimental data for the Stuttgart process from the literature and used for analyzing the different process steps. Furthermore, it was demonstrated how the model can be used for optimizing the process.
The use of vegetable oil as a fuel for agricultural and forestry vehicles allows a CO2 reduction of up to 60 %. On the other hand, the availability of vegetable oil is limited, and price competitiveness depends heavily on the respective oil price. In order to reduce the dependence on the availability of specific fuels, the joint research project “MuSt5-Trak” (Multi-Fuel EU Stage 5 Tractor) aims at developing a prototype tractor capable of running on arbitrary mixtures of diesel and rapeseed oil.
Depending on the fuel mixture used, the engine parameters need to be adapted to the respective operating conditions. For this purpose, it is necessary to detect the composition of the fuel mixture and the fuel quality. Regardless of the available fuel mixture, all functions for regular engine operation must be maintained. A conventional active regeneration of the diesel particulate filter (DPF) cannot be carried out because rapeseed oil has a flash point of 230°C, compared to 80°C for diesel fuel. This leads to a condensation of rapeseed oil while using post-injection at low and medium part load operating points, which causes a dilution of the engine oil.
In this work, engine-internal measures for achieving DPF regeneration with rapeseed oil and mixtures of diesel fuel and rapeseed oil are investigated. In order to provide stationary operating conditions in real engine operation, a “high-idle” operating point is chosen. The fuel mixtures are examined with regard to compatibility concerning a reduction of the air-fuel ratio, late combustion phasing and multiple injections. The highest temperatures are expected from a combination of these control options. After the completion of a regeneration cycle, the fuel input into the engine oil is controlled. These investigations will serve as a basis for the subsequent development of more complex regeneration strategies for close-to-reality engine operating cycles with varying load conditions.
The size congruity effect involves interference between numerical magnitude and physical size of visually presented numbers: congruent numbers (either both small or both large in numerical magnitude and physical size) are responded to faster than incongruent ones (small numerical magnitude/large physical size or vice versa). Besides, numerical magnitude is associated with lateralized response codes, leading to the Spatial Numerical Association of Response Codes (SNARC) effect: small numerical magnitudes are preferably responded to on the left side and large ones on the right side. Whereas size congruity effects are ascribed to interference between stimulus dimensions in the decision stage, SNARC effects are understood as (in)compatibilities in stimulus-response combinations. Accordingly, size congruity and SNARC effects were previously found to be independent in parity and in physical size judgment tasks. We investigated their dependency in numerical magnitude judgment tasks. We obtained independent size congruity and SNARC effects in these tasks and replicated this observation for the parity judgment task. The results confirm and extend the notion that size congruity and SNARC effects operate in different representational spaces. We discuss possible implications for number representation.
Scattering and scattering plates have a large diversity of applications. Scattering of optical and THz electromagnetic waves can be performed
with Galois scattering plates, which had found applications in acoustics first (i.e., with sound waves in concert hall acoustics). For binary
Galois scattering plates, the single scattering entities, i.e., mesas (for a binary 1) or voids (for a binary 0), have characteristic lateral dimensions
of half the wavelength of the electromagnetic waves to be scattered. Their optimal height is a quarter of the wavelength for plates used in
reflection. Meanwhile, not too elaborate lithographic techniques allow for the implementation of Galois plates for the THz range and even
for the visible spectral range. We had reported on such scattering plates before. However, in this paper, also the mathematical concept is
described and the fabrication technologies are emphasized. In contrast to the case of scattering plates with irregular surface morphologies,
Galois plate scattering is not diffuse, but there are many scattering/diffraction orders.
Recent research suggests that the common core of all aversive traits can be understood through the Dark Factor of Personality (D). Previously, the overlap among aversive traits has also been described as the low pole of HEXACO Honesty-Humility. Relying on longitudinal data and a range of theoretically derived outcome criteria, we test in four studies (total N > 2,500) whether and how D and low Honesty-Humility differ. Although the constructs shared around 66% of variance (meta-analytically aggregated across all studies), they longitudinally differently accounted for diverse aversive traits and showed theoretically meaningful and distinct associations to pretentiousness, distrust-related beliefs, and empathy. These results suggest that D and low Honesty-Humility are best understood as strongly overlapping, yet functionally different and nomologically distinct constructs.
Software defined radios can be implemented on general purpose processors (CPUs), e.g. based on a PC. A processor offers high flexibility: It can not only be used to process the data samples, but also to control receiver functions, display a waterfall or run demodulation software. However, processors can only handle signals of limited bandwidth due to their comparatively low processing speed. For signals of high bandwidth the SDR algorithms have to be implemented as custom designed digital circuits on an FPGA chip. An FPGA provides a very high processing speed, but also lacks flexibility and user interfaces. Recently the FPGA manufacturer Xilinx has
introduced a hybrid system on chip called Zynq, that combines both approaches. It features a dual ARM Cortex-A9 processor and an FPGA, that offer the flexibility of a processor with the processing speed of an FPGA on a single chip. The Zynq is therefore very interesting for use in SDRs. In this paper the
application of the Zynq and its evaluation board (Zedboard) will be discussed. As an example, a direct sampling receiver has been implemented on the Zedboard using a high-speed 16 bit ADC with 250 Msps.
Caregivers typically use a simplified mode of the language – child-directed speech (CDS) – when addressing young children. In this study, we investigate the use of complex morphological structures with a word class change within a single word in Inuktitut CDS. Inuktitut is a polysynthetic agglutinative language of the Inuit–Yupik–Unangan language family spoken in arctic Quebec, which allows more than 10 morphemes per word and in which the meaning of an entire sentence can be expressed in one word. Clearly, such a complex morphological system presents special challenges for young children, which raises the question of whether caregivers shape their CDS in ways that facilitate acquisition. Using the data from mothers addressing eight Inuktitut-speaking children aged 0;11 to 3;6, we investigated whether the frequency and complexity of polysynthetic structures in CDS are dependent on the stage of the children’s linguistic development. The results demonstrate that the number and morphological complexity of the structures with a word class change increased as the children developed linguistically. The variety of nominalizers and verbalizers – the key components of such structures – also increased through the stages and were used in variation sets, which help children acquire morphological items by providing examples of use of the same morpheme in morphologically contrasting environments. These results show the presence of morphological simplification in Inuktitut CDS and demonstrate that such simplification is fine-tuned, i.e., that mothers are sensitive to their children’s level of linguistic development.
In this paper we consider the stochastic primitive equation for geophysical flows subject to transport noise and turbulent pressure. Admitting very rough noise terms, the global existence and uniqueness of solutions to this stochastic partial differential equation are proven using stochastic maximal
-regularity, the theory of critical spaces for stochastic evolution equations, and global a priori bounds. Compared to other results in this direction, we do not need any smallness assumption on the transport noise which acts directly on the velocity field and we also allow rougher noise terms. The adaptation to Stratonovich type noise and, more generally, to variable viscosity and/or conductivity are discussed as well.
In past decades, many cities and regions have underwent structural transformations—e.g.,
in old industrialized “rust belts” or in peripheral rural areas. Many of these shrinking cities have
to face the challenges of long-term demographic and economic changes. While shrinkage is often
related to post-industrial transformations in the USA, in other countries, such as Germany, for
example, the causes are related to changing demographics with declining birth rates and the effects
of the German reunification. Many cities have tried to combat shrinkage and have thus developed
a variety of policies and strategies such as the establishing of substitute industries. To assess the
sustainability of this approach, this paper investigates the cities of Cleveland, USA and Bochum,
Germany in a comparative analysis following the most similar/most different research design. The
paper shows that substitute industries might lead to new development paths for shrinking cities.
Endocytosis of the amyloid precursor protein (APP) is critical for generation of β-amyloid, aggregating in Alzheimer's disease. APP endocytosis depending on the intracellular NPTY motif is well investigated, whereas involvement of the YTSI (also termed BaSS) motif remains controversial. Here, we show that APP lacking the YTSI motif (ΔYTSI) displays reduced localization to early endosomes and decreased internalization rates, similar to APP ΔNPTY. Additionally, we show that the YTSI-binding protein, PAT1a interacts with the Rab5 activator RME-6, as shown by several independent assays. Interestingly, knockdown of RME-6 decreased APP endocytosis, whereas overexpression increased the same. Similarly, APP ΔNPTY endocytosis was affected by PAT1a and RME-6 overexpression, whereas APP ΔYTSI internalization remained unchanged. Moreover, we could show that RME-6 mediated increase of APP endocytosis can be diminished upon knocking down PAT1a. Together, our data identify RME-6 as a novel player in APP endocytosis, involving the YTSI-binding protein PAT1a.
The quality of risk reports: Integrating requirement levels of standard setters into text analysis
(2021)
The intention of this paper is to shed light on the analysis of financial disclosure through the integration of requirement levels. This in return will lead to the development of a general applicable evaluation methodology based on Bloom's taxonomy system. Therefore, it will be possible to explicitly consider the relevance of the given information. To underline the appropriateness of our method, we combine the requirement levels with a qualitative content analysis. Based on the German accounting standard DRS 20, we clarify the respective application of the requirement levels in the context of the qualitative content analysis. Hence, we will discuss the limitations of our developed approach. In addition, we analyze further areas of application in the context of qualitative analysis of financial disclosure. All things considered, it is evident that our chosen approach, through the integration of a taxonomy system, contributes to the validity of established text analyzing methods.
Most mitochondrial proteins are synthesized in the cytosol and subsequently translocated as unfolded polypeptides into mitochondria. Cytosolic chaperones maintain precursor proteins in an import-competent state. This post-translational import reaction is under surveillance of the cytosolic ubiquitin-proteasome system, which carries out several distinguishable activities. On the one hand, the proteasome degrades nonproductive protein precursors from the cytosol and nucleus, import intermediates that are stuck in mitochondrial translocases, and misfolded or damaged proteins from the outer membrane and the intermembrane space. These surveillance activities of the proteasome are essential for mitochondrial functionality, as well as cellular fitness and survival. On the other hand, the proteasome competes with mitochondria for nonimported cytosolic precursor proteins, which can compromise mitochondrial biogenesis. In order to balance the positive and negative effects of the cytosolic protein quality control system on mitochondria, mitochondrial import efficiency directly regulates the capacity of the proteasome via transcription factor Rpn4 in yeast and nuclear respiratory factor (Nrf) 1 and 2 in animal cells. In this review, we provide a thorough overview of how the proteasome regulates mitochondrial biogenesis.
Consider the primitive equations on ◂+▸R2×(◂,▸z0,z1) with initial data a of the form a=◂+▸a1+a2, where ◂+▸a1∈◂◽.▸BUCσ(◂,▸R2;L1(◂,▸z0,z1)) and ◂+▸a2∈L
∞
σ
(◂,▸R2;L1(◂,▸z0,z1)). These spaces are scaling-invariant and represent the anisotropic character of these equations. It is shown that for a1 arbitrary large and a2 sufficiently small, this set of equations admits a unique strong solution which extends to a global one and is thus strongly globally well posed for these data provided a is periodic in the horizontal variables. The approach presented depends crucially on mapping properties of the hydrostatic Stokes semigroup in the L∞(L1)-setting. It can be seen as the counterpart of the classical iteration schemes for the Navier–Stokes equations, now for the primitive equations in the L∞(L1)-setting.
The development of a power system based on high shares of renewable energy sources puts high demands on power grids and the remaining controllable power generation plants, load management and the storage of energy. To reach climate protection goals and a significant reduction of CO2, surplus energies from fluctuating renewables have to be used to defossilize not only the power production sector but the mobility, heat and industry sectors as well, which is called sector coupling. In this article, the role of wastewater treatment plants by means of sector coupling is pictured, discussed and evaluated. The results show significant synergies—for example, using electrical surplus energy to produce hydrogen and oxygen with an electrolyzer to use them for long-term storage and enhancing purification processes on the wastewater treatment plant (WWTP). Furthermore, biofuels and storable methane gas can be produced or integrate the WWTP into a local heating network. An interconnection in many fields of different research sectors are given and show that a practical utilization is possible and reasonable for WWTPs to contribute with sustainable energy concepts to defossilization.
Comprehensive reuse and systematic evolution of reuse artifacts as proposed by the Quality Improvement Paradigm (QIP) do not only require tool support for mere storage and retrieval. Rather, an integrated management of (potentially reusable) experience data as well as project-related data is needed. This paper presents an approach exploiting object-relational database technology to implement the QIP-driven reuse repository of the SFB 501. Requirements, concepts, and implementational aspects are discussed and illustrated through a running example, namely the reuse and continuous improvement of SDL patterns for developing distributed systems. Based on this discussion, we argue that object-relational database management systems (ORDBMS) are best suited to implement such a comprehensive reuse repository. It is demonstrated how this technology can be used to support all phases of a reuse process and the accompanying improvement cycle. Although the discussions of this paper are strongly related to the requirements of the SFB 501 experience base, the basic realization concepts, and, thereby, the applicability of ORDBMS, can easily be extended to similar applications, i. e., reuse repositories in general.
Employing site-directed spin labeling (SDSL), the structure of maltose-binding protein (MBP) had previously been studied in the native state by electron paramagnetic resonance (EPR) spectroscopy. Several spin-labeled double cysteine mutants were distributed all over the structure of this cysteine-free protein and revealed distance information between the nitroxide residues from double electron–electron resonance (DEER). The results were in good agreement with the known X-ray structure. We have now extended these studies to the molten globule (MG) state, a folding intermediate, which can be stabilized around pH 3 and that is characterized by secondary but hardly any tertiary structure. Instead of clearly defined distance features as found in the native state, several additional characteristics indicate that the MG structure of MBP contains different polypeptide chain and domain orientations. MBP is also known to bind its substrate maltose even in MG state although with lower affinity. Additionally, we have now created new mutants allowing for spin labeling at or near the active site. Our data confirm an already preformed ligand site structure in the MG explaining its substrate binding capability and thus most probably serving as a nucleation center for the final native structure.
Load balancing is one of the central problems that have to be solved in parallel computation. Here, the problem of distributed, dynamic load balancing for massive parallelism is addressed. A new local method, which realizes a physical analogy to equilibrating liquids in multi-dimensional tori or hypercubes, is presented. It is especially suited for communication mechanisms with low set-up to transfer ratio occurring in tightly-coupled or SIMD systems. By successive shifting single load elements to the direct neighbors, the load is automatically transferred to lightly loaded processors. Compared to former methods, the proposed Liquid model has two main advantages. First, the task of load sharing is combined with the task of load balancing, where the former has priority. This property is valuable in many applications and important for highly dynamic load distribution. Second, the Liquid model has high efficiency. Asymptotically, it needs O(D . K . Ldiff ) load transfers to reach the balanced state in a D-dimensional torus with K processors per dimension and a maximum initial load difference of Ldiff . The Liquid model clearly outperforms an earlier load balancing approach, the nearest-neighbor-averaging. Besides a survey of related research, analytical results within a formal framework are derived. These results are validated by worst-case simulations in one-and two-dimensional tori with up to two thousand processors.
In recent decades, academia has addressed a wide range of research topics in the field of ethical decision-making. Besides a great amount of research on ethical consumption, also the domain of ethical investments increasingly moves in the focus of scholars. While in this area most research focuses on whether socially or environmentally sustainable businesses outperform traditional investments financially or investigates the character traits as well as other socio-demographic factors of ethical investors, the impact of sustainable corporate conduct on the investment intentions of private investors still requires further research. Hence, we conducted two studies to shed more light on this highly relevant topic. After discussing the current state of research, in our first empirical study, we explore whether besides the traditional triad of risk, return, and liquidity, also sustainability exerts a significant impact on the willingness to invest. As hypothesized, we find that sustainability shows a clear and decisive impact in addition to the traditional factors. In a consecutive study, we investigate deeper into the sustainability-willingness to invest link. Here, our results show that improved sustainability might not pay off in terms of investment attractiveness, however and conversely, it certainly harms to conduct business in a non-sustainable manner, which cannot even be compensated by an increased return.
The core muscles play a central role in stabilizing the head during headers in soccer. The objective of this study was to examine the influence of a fatigued core musculature on the acceleration of the head during jump headers and run headers. Acceleration of the head was measured in a pre-post-design in 68 soccer players (age: 21.5 ± 3.8 years, height: 180.0 ± 13.9 cm, weight: 76.9 ± 8.1 kg). Data were recorded by means of a telemetric 3D acceleration sensor and with a pendulum header. The treatment encompassed two exercises each for the ventral, lateral, and dorsal muscle chains. The acceleration of the head between pre- and post-test was reduced by 0.3 G (p = 0.011) in jump headers and by 0.2 G (p = 0.067) in run headers. An additional analysis of all pretests showed an increased acceleration in run headers when compared to stand headers (p < 0.001) and jump headers (p < 0.001). No differences were found in the sub-group comparisons: semi-professional vs. recreational players, offensive vs. defensive players. Based on the results, we conclude that the acceleration of the head after fatiguing the core muscles does not increase, which stands in contrast to postulated expectations. More tests with accelerated soccer balls are required for a conclusive statement.
The Influence of Case and Word Order in Child and Adult
Processing of Relative Clauses in Greek
(2022)
Previous cross-linguistic studies have shown that object relative clauses (ORCs) are typically harder to parse than subject relative clauses (SRCs). The cause of difficulty, however, is still under debate, both in the adult and in the developmental literature. The present study investigates the on-line processing of SRCs and ORCs in Greek-speaking 11- to 12-year-old children and adults, and provides evidence on relative clause processing in Greek—a free word order language. We conducted a self-paced listening task in which we manipulated the type of relative clause (SRC vs. ORC), the RC internal word order (canonical vs. scrambled), and the type of relativizer (relative pronoun vs. complementizer). The results showed that SRCs were overall processed faster than ORCs, providing evidence that children follow similar processing strategies to adults. In addition, accusative case marking facilitated the processing of non-canonical structures in adults but less so in children. Children showed heavy reliance on word order, as they processed nominative and accusative pre-verbal NPs in exactly the same way, while they were strongly garden-pathed in ORCs with post-verbal nominative NPs. We argue that these results are compatible with the Competition Model.
Muscular imbalances of the trunk muscles are held responsible for changes in body posture. At the same time, whole-body electromyostimulation (WB-EMS) has been established as a new training method that enables simultaneous stimulation of many muscle groups. This study was aiming to analyze if a 10 weeks WB-EMS training changes posture-relevant parameters and/or improves isometric strength of the trunk extensors and flexors, and if there are differences based on stimulation at 20 Hz and 85 Hz. Fifty eight untrained adult test persons were divided into three groups (control, CON; training with 20 Hz stimulation, TR20; training with 85 Hz, TR85). Anthropometric parameters, trunk extension and flexion forces and torques, and posture parameters were determined before (n = 58) and after (n = 53: CON: n = 15, TR20: n = 19, TR85: n = 19) a 10 weeks WB-EMS training program (15 applications, 9 exercises). Differences between the groups were calculated for pre- and post-tests using univariate ANOVA and between the test times using repeated (2 × 3) ANOVA. Comparisons of pairs were calculated post hoc based on Fisher (LSD). No differences between the groups were found for the posture parameters. The post hoc analysis of both trunk flexion and trunk extension forces and torques showed a significant difference between the groups TR85 and CON but no difference between the other group pairs. A 10 weeks whole-body electrostimulation training with a stimulation frequency of 85 Hz in contrast to training with a stimulation frequency of 20 Hz improves the trunk muscle strength of an untrained group but does not significantly change posture parameters.
Much reading research has found that informative parafoveal masks lead to a reading benefit for native speakers (see, Schotter et al., 2012). However, little reading research has tested the impact of uninformative parafoveal masks during reading. Additionally, parafoveal processing research is primarily restricted to native speakers. In the current study we manipulated the type of uninformative preview using a gaze contingent boundary paradigm with a group of L1 English speakers and a group of late L2 English speakers (L1 German). We were interested in how different types of uninformative masks impact on parafoveal processing, whether L1 and L2 speakers are similarly impacted, and whether they are sensitive to parafoveally viewed language-specific sub-lexical orthographic information. We manipulated six types of uninformative masks to test these objectives: an Identical, English pseudo-word, German pseudo-word, illegal string of letters, series of X’s, and a blank mask. We found that X masks affect reading the most with slight graded differences across the other masks, L1 and L2 speakers are impacted similarly, and neither group is sensitive to sub-lexical orthographic information. Overall these data show that not all previews are equal, and research should be aware of the way uninformative masks affect reading behavior. Additionally, we hope that future research starts to approach models of eye-movement behavior during reading from not only a monolingual but also from a multilingual perspective.
As a consequence of the real estate market crash after 2008, large investors invested a significant amount of wealth into single-family houses to construct a portfolio of rental dwellings, whose income is securitized in the capital. In some local housing markets, these investors own remarkable numbers of single-family houses. Furthermore, their trading activities have resulted in a new investment strategy, which exacerbates property wealth concentration and polarization. This new investment strategy and its portfolio optimization inspire curiosity about its influence on housing markets. This paper first aims to find an optimal portfolio strategy by employing an expected utility optimization from the terminal wealth, which adopts a stochastic model that includes a variety of economic states to estimate house prices. Second, it aims to analyze the effect of large investors on the housing market. The results show the investment strategies of large investors depend on the balance among economic state, maintenance cost, rental income, interest rate and investment willingness of large investors to housing and their effect depends on the state of the economy.
The impact of cognitive and motivational resources on engangement with automated formative feedback
(2024)
The effectiveness of automated formative feedback highly depends on student feedback engagement that is largely determined by learners’ cognitive and motivational resources. Yet, most studies have only investigated either cognitive resources (e.g., mental effort), or motivational resources (e.g., expectancy-value-cost variables). The purpose of this study is to examine the development (indicated by time) and relationship of 1) cognitive, 2) affective, and 3) behavioral feedback engagement as a function of cognitive and motivational resources in a computer-based learning environment with automated formative feedback. Data was collected from N = 330 German B.Ed. Elementary Education students who worked four consecutive sessions on summarizing texts. Previously invested mental effort (t-1) affected situational expectancy and cost but not situational value. 1) Cognitive feedback engagement was positively associated with previous performance but neither associated with cognitive nor motivational resources. 2) Affective feedback engagement was positively associated with intrinsic value and negatively associated with situational expectancies, invested mental effort and previous performance. 3) Behavioral feedback engagement was positively associated with situational expectancies and invested mental effort. This study contributes to the understanding of student’s cognitive and motivational structures when engaging with automated formative feedback.
We consider a variant of the generalized assignment problem (GAP) where the amount of space used in each bin is restricted to be either zero (if the bin is not opened) or above a given lower bound (a minimum quantity). We provide several complexity results for different versions of the problem and give polynomial time exact algorithms and approximation algorithms for restricted cases.
For the most general version of the problem, we show that it does not admit a polynomial time approximation algorithm (unless P=NP), even for the case of a single bin. This motivates to study dual approximation algorithms that compute solutions violating the bin capacities and minimum quantities by a constant factor. When the number of bins is fixed and the minimum quantity of each bin is at least a factor \(\delta>1\) larger than the largest size of an item in the bin, we show how to obtain a polynomial time dual approximation algorithm that computes a solution violating the minimum quantities and bin capacities by at most a factor \(1-\frac{1}{\delta}\) and \(1+\frac{1}{\delta}\), respectively, and whose profit is at least as large as the profit of the best solution that satisfies the minimum quantities and bin capacities strictly.
In particular, for \(\delta=2\), we obtain a polynomial time (1,2)-approximation algorithm.
Firn describes the interstage product between snow and ice in cold regions of the earth, where annual snow fall exceeds the amount of snow melting. The continuing accumulation of snow leads to its densificiation due to overburden stress until it becomes ice. In the field of glaciology various attempts on simulating firn densification have been made and new models are still developed, as the knowledge of the firn column's density structure allows important derivations.
The presented study reassesses a model description for low density firn based on the process of grain boundary sliding presented by Alley in 1987 [1] using an optimisation approach. By comparing simulation results to 159 measured firn density profiles from Greenland and Antarctica it finds a possible additional dependency of the constitutive relation on the mean surface mass balance. This result is interpreted as an insufficient description of the stress regime.
Background: Aneuploidy, or abnormal chromosome numbers, severely alters cell physiology and is widespread in
cancers and other pathologies. Using model cell lines engineered to carry one or more extra chromosomes, it has
been demonstrated that aneuploidy per se impairs proliferation, leads to proteotoxic as well as replication stress
and triggers conserved transcriptome and proteome changes.
Results: In this study, we analysed for the first time miRNAs and demonstrate that their expression is altered in
response to chromosome gain. The miRNA deregulation is independent of the identity of the extra chromosome
and specific to individual cell lines. By cross-omics analysis we demonstrate that although the deregulated miRNAs
differ among individual aneuploid cell lines, their known targets are predominantly associated with cell development,
growth and proliferation, pathways known to be inhibited in response to chromosome gain. Indeed, we show that up
to 72% of these targets are downregulated and the associated miRNAs are overexpressed in aneuploid cells, suggesting
that the miRNA changes contribute to the global transcription changes triggered by aneuploidy. We identified
hsa-miR-10a-5p to be overexpressed in majority of aneuploid cells. Hsa-miR-10a-5p enhances translation of a
subset of mRNAs that contain so called 5’TOP motif and we show that its upregulation in aneuploids provides
resistance to starvation-induced shut down of ribosomal protein translation.
Conclusions: Our work suggests that the changes of the microRNAome contribute on one hand to the adverse
effects of aneuploidy on cell physiology, and on the other hand to the adaptation to aneuploidy by supporting
translation under adverse conditions.
Keywords: Aneuploidy, Cancer, miRNA, miR-10a-5p, Trisomy
Cyanobacteria are ubiquitous phototrophic prokaryotes that find a wide range of
applications in industry due to their broad product spectrum. In this context, the application
of cyanobacteria as biofertilizers and thus as an alternative to artificial fertilizers has emerged
in recent decades. The benefit is mostly based on the ability of cyanobacteria to fix elemental
nitrogen and make it available to the plants in a usable form. However, the positive effects of co-
cultivating plants with cyanobacteria are not limited to the provision of nitrogen. Cyanobacteria
produce numerous secondary metabolites that can be useful for plants, for example, they can
have growth-promoting effects or increase resistance to plant diseases. The effects of biotic
and abiotic stress can as well be reduced by many secondary metabolites. Furthermore, the
biofilms formed by the cyanobacteria can lead to improved soil conditions, such as increased
water retention capacity. To exchange the substances mentioned, cyanobacteria form symbioses
with plants, whereby the strength of the symbiosis depends on both partners, and not every
plant can form symbiosis with every cyanobacterium. Not only the plants in symbiosis benefit
from the cyanobacteria, but also vice versa. This review summarizes the beneficial effects of
cyanobacterial co-cultivation on plants, highlighting the substances exchanged and the strength
of cyanobacterial symbioses with plants. A detailed explanation of the mechanism of nitrogen
fixation in cyanobacterial heterocysts is given. Finally, a summary of possible applications of
co-cultivation in the (agrar-)industry is given.
We describe a platform for the portable and secure execution of mobile agents writtenin various interpreted languages on top of a common run-time core. Agents may migrate at anypoint in their execution, fully preserving their state, and may exchange messages with otheragents. One system may contain many virtual places, each establishing a domain of logicallyrelated services under a common security policy governing all agents at this place. Agents areequipped with allowances limiting their resource accesses, both globally per agent lifetime andlocally per place. We discuss aspects of this architecture and report about ongoing work.
The structural integrity of synaptic connections critically depends on the interaction between synaptic cell adhesion molecules (CAMs) and the underlying actin and microtubule cytoskeleton. This interaction is mediated by giant Ankyrins, that act as specialized adaptors to establish and maintain axonal and synaptic compartments. In Drosophila, two giant isoforms of Ankyrin2 (Ank2) control synapse stability and organization at the larval neuromuscular junction (NMJ). Both Ank2-L and Ank2-XL are highly abundant in motoneuron axons and within the presynaptic terminal, where they control synaptic CAMs distribution and organization of microtubules. Here, we address the role of the conserved N-terminal ankyrin repeat domain (ARD) for subcellular localization and function of these giant Ankyrins in vivo. We used a P[acman] based rescue approach to generate deletions of ARD subdomains, that contain putative binding sites of interacting transmembrane proteins. We show that specific subdomains control synaptic but not axonal localization of Ank2-L. These domains contain binding sites to L1-family member CAMs, and we demonstrate that these regions are necessary for the organization of synaptic CAMs and for the control of synaptic stability. In contrast, presynaptic Ank2-XL localization only partially depends on the ARD but strictly requires the presynaptic presence of Ank2-L demonstrating a critical co-dependence of the two isoforms at the NMJ. Ank2-XL dependent control of microtubule organization correlates with presynaptic abundance of the protein and is thus only partially affected by ARD deletions. Together, our data provides novel insights into the synaptic targeting of giant Ankyrins with relevance for the control of synaptic plasticity and maintenance.
Several studies now document the disproportionate distribution of environmental pollution across different groups, but many are based on aggregated data or subjective pollution measures. In this study, we describe the air quality disadvantage of migrants in Germany using objective pollution data linked to nationally representative individual-level survey data. We intersect 1 × 1 km2 grid geo-references from the German General Social Survey (ALLBUS) 2014, 2016, and 2018 with 2 × 2 km2 estimates of annually averaged air pollution by the German Environment Agency for nitrogen dioxide, ozone, and particulate matter. Respondents with a migration background are exposed to higher levels of nitrogen dioxide and particulate matter than people of German descent. Urbanity of residence partly explains these differences, up to 81 per cent for particulate matter and about 30 per cent for other pollutants. A larger proportion of immigrants live in larger cities, which are more prone to high levels of air pollution. This is especially true for second-generation migrants. Income differences, on the other hand, do not explain the migrant disadvantage. In city fixed effects models, the patterns for migration background point unambiguously in the direction of environmental disadvantage for all pollutants except ozone. However, the within-municipality associations are weak.
We consider N coupled linear oscillators with time-dependent coecients. An exact complex amplitude - real phase decomposition of the oscillatory motion is constructed. This decomposition is further used to derive N exact constants of motion which generalise the so-called Ermakov-Lewis invariant of a single oscillator. In the Floquet problem of periodic oscillator coecients we discuss the existence of periodic complex amplitude functions in terms of existing Floquet solutions.