On a General Notion of Transformation for Multiagent Systems and its Implementation

The focus of this contribution is on the construction of a transformation system for Multiagent Systems (MAS) based on categorical notions. Based on former work on the categorical modeling of MAS the category MAS of all Multiagent Systems is introduced. A transformation system over this category is established using the Double Pushout Approach. For illustration we present a simple example. First steps of implementational work are described

Characterizing Van Kampen Squares via Descent Data

Categories in which cocones satisfy certain exactness conditions w.r.t. pullbacks are subject to current research activities in theoretical computer science. Usually, exactness is expressed in terms of properties of the pullback functor associated with the cocone. Even in the case of non-exactness, researchers in model semantics and rewriting theory inquire an elementary characterization of the image of this functor. In this paper we will investigate this question in the special case where the cocone is a cospan, i.e. part of a Van Kampen square. The use of Descent Data as the dominant categorical tool yields two main results: A simple condition which characterizes the reachable part of the above mentioned functor in terms of liftings of involved equivalence relations and (as a consequence) a necessary and sufficient condition for a pushout to be a Van Kampen square formulated in a purely algebraic manner.Comment: In Proceedings ACCAT 2012, arXiv:1208.430

Category Theory and Model-Driven Engineering: From Formal Semantics to Design Patterns and Beyond

There is a hidden intrigue in the title. CT is one of the most abstract mathematical disciplines, sometimes nicknamed "abstract nonsense". MDE is a recent trend in software development, industrially supported by standards, tools, and the status of a new "silver bullet". Surprisingly, categorical patterns turn out to be directly applicable to mathematical modeling of structures appearing in everyday MDE practice. Model merging, transformation, synchronization, and other important model management scenarios can be seen as executions of categorical specifications. Moreover, the paper aims to elucidate a claim that relationships between CT and MDE are more complex and richer than is normally assumed for "applied mathematics". CT provides a toolbox of design patterns and structural principles of real practical value for MDE. We will present examples of how an elementary categorical arrangement of a model management scenario reveals deficiencies in the architecture of modern tools automating the scenario.Comment: In Proceedings ACCAT 2012, arXiv:1208.430

Bisimulation of Labeled State-to-Function Transition Systems of Stochastic Process Languages

Labeled state-to-function transition systems, FuTS for short, admit multiple transition schemes from states to functions of finite support over general semirings. As such they constitute a convenient modeling instrument to deal with stochastic process languages. In this paper, the notion of bisimulation induced by a FuTS is proposed and a correspondence result is proven stating that FuTS-bisimulation coincides with the behavioral equivalence of the associated functor. As generic examples, the concrete existing equivalences for the core of the process algebras ACP, PEPA and IMC are related to the bisimulation of specific FuTS, providing via the correspondence result coalgebraic justification of the equivalences of these calculi.Comment: In Proceedings ACCAT 2012, arXiv:1208.430

The Depletion of Nuclear Glutathione Impairs Cell Proliferation in 3t3 Fibroblasts

BACKGROUND:Glutathione is considered essential for survival in mammalian cells and yeast but not in prokaryotic cells. The presence of a nuclear pool of glutathione has been demonstrated but its role in cellular proliferation and differentiation is still a matter of debate. PRINCIPAL FINDINGS:We have studied proliferation of 3T3 fibroblasts for a period of 5 days. Cells were treated with two well known depleting agents, diethyl maleate (DEM) and buthionine sulfoximine (BSO), and the cellular and nuclear glutathione levels were assessed by analytical and confocal microscopic techniques, respectively. Both agents decreased total cellular glutathione although depletion by BSO was more sustained. However, the nuclear glutathione pool resisted depletion by BSO but not with DEM. Interestingly, cell proliferation was impaired by DEM, but not by BSO. Treating the cells simultaneously with DEM and with glutathione ethyl ester to restore intracellular GSH levels completely prevented the effects of DEM on cell proliferation. CONCLUSIONS:Our results demonstrate the importance of nuclear glutathione in the control of cell proliferation in 3T3 fibroblasts and suggest that a reduced nuclear environment is necessary for cells to progress in the cell cycle

Over-expression of mitochondrial creatine kinase in the murine heart improves functional recovery and protects against injury following ischaemia–reperfusion

Aims Mitochondrial creatine kinase (MtCK) couples ATP production via oxidative phosphorylation to phosphocreatine in the cytosol, which acts as a mobile energy store available for regeneration of ATP at times of high demand. We hypothesized that elevating MtCK would be beneficial in ischaemia–reperfusion (I/R) injury. Methods and results Mice were created over-expressing the sarcomeric MtCK gene with αMHC promoter at the Rosa26 locus (MtCK-OE) and compared with wild-type (WT) littermates. MtCK activity was 27% higher than WT, with no change in other CK isoenzymes or creatine levels. Electron microscopy confirmed normal mitochondrial cell density and mitochondrial localization of transgenic protein. Respiration in isolated mitochondria was unaltered and metabolomic analysis by 1 H-NMR suggests that cellular metabolism was not grossly affected by transgene expression. There were no significant differences in cardiac structure or function under baseline conditions by cine-MRI or LV haemodynamics. In Langendorff-perfused hearts subjected to 20 min ischaemia and 30 min reperfusion, MtCK-OE exhibited less ischaemic contracture, and improved functional recovery (Rate pressure product 58% above WT; P < 0.001). These hearts had reduced myocardial infarct size, which was confirmed in vivo: 55 ± 4% in WT vs. 29 ± 4% in MtCK-OE; P < 0.0001). Isolated cardiomyocytes from MtCK-OE hearts exhibited delayed opening of the mitochondrial permeability transition pore (mPTP) compared to WT, which was confirmed by reduced mitochondrial swelling in response to calcium. There was no detectable change in the structural integrity of the mitochondrial membrane. Conclusions Modest elevation of MtCK activity in the heart does not adversely affect cellular metabolism, mitochondrial or in vivo cardiac function, but modifies mPTP opening to protect against I/R injury and improve functional recovery. Our findings support MtCK as a prime therapeutic target in myocardial ischaemia

Synthetic Nanoparticles for Vaccines and Immunotherapy

The immune system plays a critical role in our health. No other component of human physiology plays a decisive role in as diverse an array of maladies, from deadly diseases with which we are all familiar to equally terrible esoteric conditions: HIV, malaria, pneumococcal and influenza infections; cancer; atherosclerosis; autoimmune diseases such as lupus, diabetes, and multiple sclerosis. The importance of understanding the function of the immune system and learning how to modulate immunity to protect against or treat disease thus cannot be overstated. Fortunately, we are entering an exciting era where the science of immunology is defining pathways for the rational manipulation of the immune system at the cellular and molecular level, and this understanding is leading to dramatic advances in the clinic that are transforming the future of medicine.1,2 These initial advances are being made primarily through biologic drugs– recombinant proteins (especially antibodies) or patient-derived cell therapies– but exciting data from preclinical studies suggest that a marriage of approaches based in biotechnology with the materials science and chemistry of nanomaterials, especially nanoparticles, could enable more effective and safer immune engineering strategies. This review will examine these nanoparticle-based strategies to immune modulation in detail, and discuss the promise and outstanding challenges facing the field of immune engineering from a chemical biology/materials engineering perspectiveNational Institutes of Health (U.S.) (Grants AI111860, CA174795, CA172164, AI091693, and AI095109)United States. Department of Defense (W911NF-13-D-0001 and Awards W911NF-07-D-0004

Qualitätsverbesserung von MC Fragen [Quality assurance of Multiple Choice Questions]

[english] Because of the missing relevance of graded examinations at the German medical faculties, there was no need to reflect the question quality in written examinations consistently. Through the new national legislation for medical education certification-relevant, faculty-internal examinations are prescribed. Until now, there is a lack of structures and processes which could lead to an improvement of the question quality. To reflect the different performance of the students, a different severity and a good selectivity of the test questions are necessary. For a interdisciplinary examination for fourth year undergraduate students at the University Hospital Duesseldorf, new Multiple choice (MC)- questions which are application-orientated, clearly formulated and to a large extent free from formal errors should be developed. The implementation took place in the conception and performance of Workshops for the construction of MC-questions and the appointment of an interdisciplinary review-committee. It could be shown that an author training facilitates and accelerates the review-process for the committee and that a review process reflects itself in a high practise-orientation of the items. Prospectively, high-quality questions which are created in a review-process and metrological analysed could be read into inter-university databases. Therewith the initial expenditure of time could be reduced. The interdisciplinary constitution of the review-committee offers the possibility of an intensified discussion over content and relevance of the questions. <br>[german] Wegen fehlender notenrelevanter Prüfungen an den Medizinischen Fakultäten in Deutschland bestand bisher keine Notwendigkeit, die Fragenqualität in schriftlichen Prüfungen konsequent zu reflektieren. Erst durch die neue Approbationsordnung sind zeugnisrelevante, fakultätsinterne Prüfungen vorgeschrieben. Es fehlen somit oftmals Strukturen und Prozesse, die zu einer Verbesserung der Fragenqualität führen. Damit die Klausuren das unterschiedliche Leistungsspektrum der Studierenden widerspiegeln, sind u.a. unterschiedliches Schwierigkeitsniveau und eine gute Trennschärfe der Prüfungsfragen notwendig. Für eine fachübergreifende Klausur des vierten Studienjahres an der Universität Düsseldorf sollten neue MC -Fragen entwickelt werden, die anwendungsorientiert prüfen, eindeutig formuliert und weitgehend frei von formalen Fehlern sind. Die Umsetzung erfolgte in der Konzeption und Durchführung von Workshops zur Erstellung von MC-Fragen für Fragenautoren und die Einrichtung eines interdisziplinären Reviewkomitees. Es konnte gezeigt werden, dass eine Autorenschulung den Reviewprozess für das Reviewkomitee erleichtert und beschleunigt. Der Nutzen des Reviewprozesses spiegelt sich in einer hohen Anwendungsorientierung der einzelnen Items wider. Hochwertige, in einem Reviewverfahren erstellte und messtechnisch analysierte Prüfungsfragen könnten künftig in interuniversitäre Datenbanken eingegeben werden und damit den anfänglich erforderlichen Zeitaufwand relativieren. Durch die interdisziplinäre Zusammensetzung des Reviewkomitees bietet sich außerdem die Möglichkeit einer verstärkten Diskussion über die Inhalte der Prüfungsfragen