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Propionic acidemia in a previously healthy adolescent with acute onset of dilated cardiomyopathy
(2014)
This review is divided into two interconnected parts, namely a biological and a chemical one. The focus of the first part is on the biological background for constructing tissue-engineered vascular grafts to promote vascular healing. Various cell types, such as embryonic, mesenchymal and induced pluripotent stem cells, progenitor cells and endothelial- and smooth muscle cells will be discussed with respect to their specific markers. The in vitro and in vivo models and their potential to treat vascular diseases are also introduced. The chemical part focuses on strategies using either artificial or natural polymers for scaffold fabrication, including decellularized cardiovascular tissue. An overview will be given on scaffold fabrication including conventional methods and nanotechnologies. Special attention is given to 3D network formation via different chemical and physical cross-linking methods. In particular, electron beam treatment is introduced as a method to combine 3D network formation and surface modification. The review includes recently published scientific data and patents which have been registered within the last decade.
During space missions astronauts suffer from cardiovascular deconditioning, when they are exposed to microgravity conditions. Until now, no specific drugs are available for effective countermeasures, since the underlying mechanism is not completely understood. Endothelial cells (ECs) and smooth muscle cells (SMCs) play crucial roles in a variety of cardiovascular functions, many of which are regulated via P2 receptors. However, their function in ECs and SMCs under microgravity condition is still unknown. In this study, ECs and SMCs were isolated from bovine aorta and differentiated from human mesenchymal stem cells (hMSCs), respectively. Subsequently, the cells were verified based on specific markers. An altered P2 receptor expression pattern was detected during the commitment of hMSC towards ECs and SMCs. The administration of natural and artificial P2 receptor agonists and antagonists directly affected the differentiation process. By using EC growth medium as conditioned medium, a vessel cell model was created to culture SMCs and vice versa. Within this study, we were able to show for the first time that the expression of some P2 receptors were altered in ECs and SMCs grown for 24h under simulated microgravity conditions. On the other hand, in some P2 receptor expressions such as P2X7 conditioned medium compensated this change.
In conclusion, our data show that P2 receptors play an important functional role in hMSC differentiation towards ECs and SMCs. Since some P2 receptor artificial ligands are already used as drugs for patients with cardiovascular diseases, it is reasonable to assume that in the future they might be promising candidates for treating cardiovascular deconditioning.
Social cash transfers (SCTs) are considered a priority in least-developed countries, where the gap between the need for basic social protection and existing provisions is greatest. This study represents one of the first comprehensive treatments of the impact of social cash transfers in low-income sub-Saharan Africa, and the first for Zambia's oldest SCT scheme. The results, based on propensity score matching and fully efficient odds-weighted regression, and data from the Kalomo SCT pilot scheme, confirm positive SCT effects on per capita consumption expenditure. We also discover threshold effects with SCT mostly impacting food expenditure among poorer beneficiary households and non-food expenditure among wealthier beneficiaries.
Analytical pyrolysis technique hyphenated to gas chromatography/mass spectrometry (Py-GC/MS) has extended the range of possible tools for characterization of synthetic polymers/copolymers. Pyrolysis involves thermal fragmentation of the analytical sample at elevated temperature between 500 and 1400 °C. In the presence of an inert gas, reproducible decomposition products characteristic for the original polymer/copolymer sample are formed. The pyrolysis products are chromatographically separated by using a fused silica capillary column and subsequently identified by interpretation of the obtained mass spectra or by using mass spectra libraries. The analytical technique eliminate the need for pre-treatment by performing analyses directly on the solid or liquid polymer sample.
In this paper, application examples of the analytical pyrolysis hyphenated to gas chromatography/mass spectrometry for the identification of different polymeric materials in the plastic and automotive industry, dentistry and occupational safety are demonstrated. For the first time results of identification of commercially light-curing dental filling material and a car wrapping foil by pyrolysis-GC/MS are presented.
Exposure to microgravity conditions causes cardiovascular deconditioning in astronauts during spaceflight. Until now, no specific drugs are available for countermeasure, since the underlying mechanism is largely unknown. Endothelial cells (ECs) and smooth muscle cells (SMCs) play key roles in various vascular functions, many of which are regulated by purinergic 2 (P2) receptors. However, their function in ECs and SMCs under microgravity conditions is still unclear. In this study, primary ECs and SMCs were isolated from bovine aorta and verified with specific markers. We show for the first time that the P2 receptor expression pattern is altered in ECs and SMCs after 24 h exposure to simulated microgravity using a clinostat. However, conditioned medium compensates this change in specific P2 receptors, for example, P2X7. Notably, P2 receptors such as P2X7 might be the important players during the paracrine interaction. Additionally, ECs and SMCs secreted different cytokines under simulated microgravity, leading into a pathogenic proliferation and migration. In conclusion, our data indicate P2 receptors might be important players responding to gravity changes in ECs and SMCs. Since some artificial P2 receptor ligands are applied as drugs, it is reasonable to assume that they might be promising candidates against cardiovascular deconditioning in the future.
The analytical pyrolysis technique hyphenated to gas chromatography–mass spectrometry (GC–MS) has extended the range of possible tools for the characterization of synthetic polymers and copolymers. Pyrolysis involves thermal fragmentation of the analytical sample at temperatures of 500–1400 °C. In the presence of an inert gas, reproducible decomposition products characteristic for the original polymer or copolymer sample are formed. The pyrolysis products are chromatographically separated using a fused-silica capillary column and are subsequently identified by interpretation of the obtained mass spectra or by using mass spectra libraries. The analytical technique eliminates the need for pretreatment by performing analyses directly on the solid or liquid polymer sample. In this article, application examples of analytical pyrolysis hyphenated to GC–MS for the identification of different polymeric materials in the plastic and automotive industry, dentistry, and occupational safety are demonstrated. For the first time, results of identification of commercial light-curing dental filling material and a car wrapping foil by pyrolysis–GC–MS are presented.
It is a euphemism to say that humans use tools. Humans possess a vast repertoire of tools they use every day. In fact, as language or bipedal locomotion, tool use is a hallmark of humans. Tool use has also been often viewed as an important step during evolution (van Schaik et al., 1999) or even as a marker of the evolution of human intelligence (Wynn, 1985). So a fundamental issue is, what are the cognitive and neural bases of human tool use? The present series of papers in this special topic represents the newest additions to that research topic.
Simulation of thermal behavior during friction stir welding process for predicting residual stresses
(2014)
Improving the study entry supports students in a decisive phase of their university education. Implementing improvements is a change process and can only be successful if the relevant stakeholders are addressed and convinced. In the described Teaching Quality Pact project evaluation data is used as a mean to discuss in the university the situation of the study programs. As these discussions were based on empirical data rather than on opinion, it was possible to achieve an open discussion about measures that are implemented. The open discussion is maintained during the project when results of the measures taken are analyzed.
This article describes an approach to rapidly prototype the parameters of a Java application run on the IBM J9 Virtual Machine in order to improve its performance. It works by analyzing VM output and searching for behavioral patterns. These patterns are matched against a list of known patterns for which rules exist that specify how to adapt the VM to a given application. Adapting the application is done by adding parameters and changing existing ones. The process is fully automated and carried out by a toolkit. The toolkit iteratively cycles through multiple possible parameter sets, benchmarks them and proposes the best alternative to the user. The user can, without any prior knowledge about the Java application or the VM improve the performance of the deployed application and quickly cycle through a multitude of different settings to benchmark them. When tested with the representative benchmarks, improvements of up to 150% were achieved.
In general, mathematics plays a central role in our lives because today mathematics regulates our everyday life with techniques, technologies and procedures, for example coding techniques for credit cards or the drafting of curves and surfaces for construction procedures [5]. Obviously, mathematics continues to be an important element of engineering education and it still represents a major obstacle for the students. Lacking the knowledge of several topics, changing learning behavior and inadequate overall conditions at universities for the repetition of school mathematics were mentioned to be causes for the constantly increasing gap between the initial level of mathematics at university and the prior knowledge of the first semester students [2].
This thesis presents an approach to automatically adjust the parameters of a Java application run on the IBM J9 Virtual Machine in order to improve its performance. It works by analyzing the logfile the VM generates and searching for specific behavioral patterns. These patterns are matched against a list of known patterns for which rules exist that specify how to adapt the VM to the given application. Adapting the application is done by adding parameters and changing existing ones, for example to achieve a better heap usage. The process is fully automated and carried out by a toolkit developed for this thesis. The toolkit iteratively cycles through multiple possible parameter sets, benchmarks them and proposes the best alternative to the user. The user can, without any prior knowledge about the Java application or the VM improve the performance of the deployed application.
Improving data acquisition techniques and rising computational power keep producing more and larger data sets that need to be analyzed. These data sets usually do not fit into a GPU's memory. To interactively visualize such data with direct volume rendering, sophisticated techniques for problem domain decomposition, memory management and rendering have to be used. The volume renderer Volt is used to show how CUDA is efficiently utilised to manage the volume data and a GPU's memory with the aim of low opacity volume renderings of large volumes at interactive frame rates.
Abstract Classical ballet requires dancers to exercise significant muscle control and strength both while stationary and when moving. Following the Royal Academy of Dance (RAD) syllabus, 8 male and 27 female dancers (aged 20.2 + 1.9 yr) in a full-time university undergraduate dance training program were asked to stand in first position for 10 seconds and then perform 10 repeats of a demi-plié exercise to a counted rhythm. Accelerometer records from the wrist, sacrum, knee and ankle were compared with the numerical scores from a professional dance instructor. The sacrum mounted sensor detected lateral tilts of the torso in dances with lower scores (Spearman’s rank correlation coefficient r = -0.64, p < 0.005). The 5RMS6 acceleration amplitude of wrist mounted sensor was linearly correlated to the movement scores (Spearman’s rank correlation coefficient r = 0.63, p < 0.005). The application of sacrum and wrist mounted sensors for biofeedback during dance training is a realistic, low cost option.
The analytical pyrolysis technique hyphenated to gas chromatography–mass spectrometry (GC–MS) has extended the range of possible tools for the characterization of synthetic polymers and copolymers. Pyrolysis involves thermal fragmentation of the analytical sample at temperatures of 500–1400 °C. In the presence of an inert gas, reproducible decomposition products characteristic for the original polymer or copolymer sample are formed. The pyrolysis products are chromatographically separated using a fused-silica capillary column and are subsequently identified by interpretation of the obtained mass spectra or by using mass spectra libraries. The analytical technique eliminates the need for pretreatment by performing analyses directly on the solid or liquid polymer sample. In this article, application examples of analytical pyrolysis hyphenated to GC–MS for the identification of different polymeric materials in the plastic and automotive industry, dentistry, and occupational safety are demonstrated. For the first time, results of identification of commercial light-curing dental filling material and a car wrapping foil by pyrolysis–GC–MS are presented.
It has become increasingly clear that caspases, far from being merely cell death effectors, have a much wider range of functions within the cell. These functions are as diverse as signal transduction and cytoskeletal remodeling, and caspases are now known to have an essential role in cell proliferation, migration, and differentiation. There is also evidence that apoptotic cells themselves can direct the behavior of nearby cells through the caspase-dependent secretion of paracrine signaling factors. In some processes, including the differentiation of skeletal muscle myoblasts, both caspase activation in differentiating cells as well as signaling from apoptotic cells has been reported. Here, we review the non-apoptotic outcomes of caspase activity in a range of different model systems and attempt to integrate this knowledge.
The usage of the Web has experienced a vertiginous growth in the last few years. Watching video online has been one major driving force for this growth lately. Until the appearance of the HTML5 agglomerate of (still draft) specifications, the access and consumption of multimedia content in the Web has not been standardized. Hence, the use of proprietary Web browser plugins flourished as intermediate solution. With the introduction of the HTML5 VideoElement, Web browser plugins are replaced with a standardized alternative. Still, HTML5 Video is currently limited in many respects, including the access to only file-based media. This paper investigates on approaches to develop video live streaming solutions based on available Web standards. Besides a pull-based design based on HTTP, a push-based architecture is introduced, making use of the WebSocket protocol being part of the HTML5 standards family as well. The evaluation results of both conceptual principles emphasize, that push-based approaches have a higher potential of providing resource and cost efficient solutions as their pull-based counterparts. In addition, initial approaches to instrument the proposed push-based architecture with adaptiveness to network conditions have been developed.
SOA-Readiness of REST
(2014)
Service Security Revisited
(2014)
Robots, which are able to carry out their tasks robustly in real world environments, are not only desirable but necessary if we want them to be more welcome for a wider audience. But very often they may fail to execute their actions successfully because of insufficient information about behaviour of objects used in the actions.
This book constitutes the proceedings of the 14th International Conference on Relational and Algebraic Methods in Computer Science, RAMiCS 2014 held in Marienstatt, Germany, in April/May 2014. The 25 revised full papers presented were carefully selected from 37 submissions. The papers are structured in specific fields on concurrent Kleene algebras and related formalisms, reasoning about computations and programs, heterogeneous and categorical approaches, applications of relational and algebraic methods and developments related to modal logics and lattices.
Unexpected Situations in Service Robot Environment: Classification and Reasoning Using Naive Physics
(2014)
In the field of domestic service robots, recovery from faults is crucial to promote user acceptance. In this context we focus in particular on some specific faults, which arise from the interaction of a robot with its real world environment. Even a well-modelled robot may fail to perform its tasks successfully due to unexpected situations, which occur while interacting. These situations occur as deviations of properties of the objects (manipulated by the robot) from their expected values. Hence, they are experienced by the robot as external faults.
As soon as data is noisy, knowledge as it is represented in an information system becomes unreliable. Features in databases induce equivalence relations—but knowledge discovery takes the other way round: given a relation, what could be a suitable functional description? But the relations we work on are noisy again. If we expect to record data for learning a classification of objects then it can well be the real data does not create a reflexive, symmetric and transitive relation although we know it should be. The usual approach taken here is to build the closure in order to ensure desired properties. This, however, leads to overgeneralisation rather quickly.
On nothing
(2014)
Many e-Learning-basedoffers, such as international programs and MOOCs have long since overcome the concept of national education and are designed to attract learners distributed throughout the world. In order to cope with the differences between learners, related offers often include opportunities to support the particular learning styles and learning pace beyond the advantages, which the technology itself naturally provides. Examples arethe individual configuration of the learning platformand display of contents and the provision of stylistically diverse and supplementary learning material. Such measures are relatively easy to implement andonce established, do not generate further expenses. Just, is it appropriate to lay the full responsibility for designing a comfortable (and supportive) learning environment into the hands of the learners and do they get along with such a responsibility? We asked university students from three continents regarding their expectations towards instructor-support and found major differences.
Open Educational Resources in the Context of School Education: Barriers and possible solutions
(2014)
Due to the increasing professional mobility of their parents, pupils often find themselves in new and unfamiliar learning scenarios in foreign contexts and countries. Besides having to leave their familiar environments, these pupils additionally may face language barriers, different curricula, and have to cope with foreign cultures. Printed textbooks, which are the most commonly used educational resources in schools, provide little support for these pupils to manage the new challenges. Teachers are the professionals designated to provide the necessary support. However, they often may not fully appreciate the pupils’ individual challenges. Possible solutions could be the provision of alternative learning contents in the pupils’ native languages and an international open exchange of knowledge and experiences amongst schoolteachers. These issues are addressed by the Open Discovery Space platform. In order to empower this platform to provide the best possible support to teachers, we explored barriers to adoption of Open Educational Practices in the context of school education and asked for manageable solutions. The investigation took place in an action research scenario. After an introduction of the ODS project, we will present the identified barriers and recommendations for solutions to overcome these, and the mechanisms which we are going to implement in the ODS platform in order to provide the best possible support to the community.
Open educational resources (OERs) provide opportunities as enablers of societal development, but they also create new challenges. From the perspective of content providers and educational institutions, particularly, cultural and context-related challenges emerge. Even though barriers regarding large-scale adoption of OERs are widely discussed, empirical evidence for determining challenges in relation to particular contexts is still rare. Such context-specific barriers generally can jeopardize the acceptance of OERs and, in particular, social OER environments. We conducted a large-scale (N = 855) cross-European investigation in the school context to determine how teachers and learners perceive cultural distance as a barrier against the use of social OER environments. The findings indicate how nationality and age of the respondents are strong predictors of cultural distance barrier. The study concludes with identification of context-sensitive interventions for overcoming the related bar riers. These consequences are vital for OER initiatives and educational institutions for aligning their efforts on OER.
The Learning Culture Survey: An international research project on cultural learning attitudes
(2014)
Dieses Dokument beinhaltet die englische Version des standardisierten Fragebogens für das fortlaufende, internationale Forschungvorhaben "Learning Culture Survey". Die Bereitstellung des Fragebogens in dieser Form dient lediglich der Möglichkeit zur Prüfung und zur Kenntnisnahme. Der Entsprechend dem Forschungsdesign ist der Fragebogen in seiner Onlineversion zu verwenden.
After an introduction, we discuss the conflicts that occurred in a highly experimental course setting, in which we implemented a student-centered course in urban higher education with a constructivist, blended-learning design. We analyse to which extent the cultural country profiles from our Learning Culture Survey suffice to prevent intercultural conflicts in education and provide support for the design of respective interventions.
People are getting older because of the demographic changes and the rate of disabled people is also going up. This article shows the challenge for BPMTool developer due to these circumstances. It illustrates how these changes impact the usage of BPM-Tools based on an Evaluation of an exemplary BPMTool (Cooper & Patterson, 2007) in terms of IT-Usability and IT-Accessibility. This evaluation was conducted in a research laboratory at the university.
PhD Project Management
(2014)
We consider the Hopfield model with n neurons and an increasing number p=p(n) of randomly chosen patterns and use Stein's method to obtain rates of convergence for the central limit theorem of overlap parameters, which holds for every fixed choice of the overlap parameter for almost all realisations of the random patterns.
Low power dissipation is a current topic in digital design, and therefore, it should be covered in a state-of-the-art electrical engineering curriculum. This paper describes how low-power design can be addressed within a digital design course. Doing so would be beneficial for both topics because low-power design is not detached from the systems perspective, and the digital design course would be enriched by references to current challenges and applications. Thus, the presented course should serve as an example of how a course can be developed to also teach students about sustainable engineering.
Matrix metalloproteinases (MMPs) are matrix-degrading enzymes that are over-expressed in joints of rheumatoid arthritis (RA) patients. However, the contribution of specific MMPs for the development of arthritic joints is unknown. This study is aimed at studying the role of matrix metalloproteinase-9 (MMP-9) in mice, using the K/BxN serum-transfer model of RA. Arthritis was induced in Balb/c mice by injecting K/BxN serum. Development of arthritis was followed in these mice by measuring ankle thickness and clinical index score. MMP-9 expression in the joints of mice killed at various time points during the disease progression was determined by gelatin zymography using ankle lysates. We found that MMP-9 expression increased with the severity of arthritis. Importantly MMP-9 deficient mice injected with K/BxN serum showed a milder form of arthritis in comparison to the control C57BL/6 mice injected with K/BxN serum. We therefore conclude that MMP-9 promotes arthritis in mice.
The RoCKIn@Work Challenge
(2014)
The RoCKIn@Home Challenge
(2014)
The objective of this research project is to develop a user-friendly and cost-effective interactive input device that allows intuitive and efficient manipulation of 3D objects (6 DoF) in virtual reality (VR) visualization environments with flat projections walls. During this project, it was planned to develop an extended version of a laser pointer with multiple laser beams arranged in specific patterns. Using stationary cameras observing projections of these patterns from behind the screens, it is planned to develop an algorithm for reconstruction of the emitter’s absolute position and orientation in space. Laser pointer concept is an intuitive way of interaction that would provide user with a familiar, mobile and efficient navigation though a 3D environment. In order to navigate in a 3D world, it is required to know the absolute position (x, y and z position) and orientation (roll, pitch and yaw angles) of the device, a total of 6 degrees of freedom (DoF). Ordinary laser-based pointers when captured on a flat surface with a video camera system and then processed, will only provide x and y coordinates effectively reducing available input to 2 DoF only. In order to overcome this problem, an additional set of multiple (invisible) laser pointers should be used in the pointing device. These laser pointers should be arranged in a way that the projection of their rays will form one fixed dot pattern when intersected with the flat surface of projection screens. Images of such a pattern will be captured via a real-time camera-based system and then processed using mathematical re-projection algorithms. This would allow the reconstruction of the full absolute 3D pose (6 DoF) of the input device. Additionally, multi-user or collaborative work should be supported by the system, would allow several users to interact with a virtual environment at the same time. Possibilities to port processing algorithms into embedded processors or FPGAs will be investigated during this project as well.
The central concept behind Open Educational Resources (OER) is opening up the access to educational resources for stakeholders who are not the usual target user group. This concept must be perceived as innovative because it describes a general economic and social paradigm shift: Education, which formerly was limited to a specific group of learners, now, is promoted as a public good. However, despite very good intentions, internationally agreed quality standards, and the availability of the required technological infrastructure, the critical threshold is not yet met. Due to several reasons, the usefulness of OER is often limited to the originally targeted context. Questions arise if the existing quality standards for Technology Enhanced Learning (TEL) actually meet the specific requirements within the OER value chain, if the existing quality standards are applicable to OER in a meaningful way, and under which conditions related standards generally could support the exploitation of OER. We analyze quality standards for TEL and contrast the life cycle model of commercial learning resources against the life cycle model of OER. We investigate special demands on quality from the context of OER and, taking the former results into account, derive emergent quality criteria for OER. The paper concludes with recommendations for the design of OER and a future standard development.
Culture, at least to some extent, is related to particular (individual and collective) experiences. In terms of education, this means that a learner, who experienced particular services in his/her past, might perceive such services as usual for educational culture and thus, expect them to be delivered in any kind of learning scenario. In German universities, education is meant to be a full-time job and usually is designed to provide a broad basis of theoretical and methodological knowledge. Achieving methodological competences is a core goal of German academic education: Once a student leaves the university, he/she is expected to decide about appropriate methods for any kind of problem (in the field of study and beyond) and how to modify the known methods in case of need. In contrast, in professional training, the learners have to study in extra-occupational situations (time is a serious issue) and might expect training that pointedly prepares them for very specific tasks. We assumed that scenarios of professional training have their own educational cultures. When designing learning contents and learning scenarios for professional training, it might be essential for the learning success to meet the learners’ expectations and contextual peculiarities.
We found remarkable differences between the results of the investigated enterprises, but even more significant diversity between the results of the German enterprises and the priory investigated German universities. As a general conclusion we can assume that generalizing research results that were solely achieved from national university students might lead to an inappropriate design of learning scenarios for particular professional contexts. Professional training for a particular enterprise should be developed according to its specific educational culture.
The Project SupraMetall: Towards Commercial Fabrication of High-Temperature Superconducting Tapes
(2014)
Methylmalonic and propionic acidemia (MMA/PA) are inborn errors of metabolism characterized by accumulation of propionic acid and/or methylmalonic acid due to deficiency of methylmalonyl-CoA mutase (MUT) or propionyl-CoA carboxylase (PCC). MMA has an estimated incidence of ~ 1: 50,000 and PA of ~ 1:100'000 -150,000. Patients present either shortly after birth with acute deterioration, metabolic acidosis and hyperammonemia or later at any age with a more heterogeneous clinical picture, leading to early death or to severe neurological handicap in many survivors. Mental outcome tends to be worse in PA and late complications include chronic kidney disease almost exclusively in MMA and cardiomyopathy mainly in PA. Except for vitamin B12 responsive forms of MMA the outcome remains poor despite the existence of apparently effective therapy with a low protein diet and carnitine. This may be related to under recognition and delayed diagnosis due to nonspecific clinical presentation and insufficient awareness of health care professionals because of disease rarity.