Isospin equilibration in relativistic heavy-ion collisions

We study the mixing and the kinetic equilibration of projectile and target nucleons in relativistic heavy-ion collisions in the energy regime between 150~AMeV and 2~AGeV in a coupled-channel BUU (CBUU) approach. We find that equilibrium in the projectile-target degrees of freedom is in general not reached even for large systems at low energy where elastic nucleon-nucleon collisions dominate. Inelastic nucleon excitations are more favorable for equilibration and their relative abundance increases both with energy and mass. Experimentally, the projectile/target admixture can be determined by measuring the degree of isospin equilibration in isospin asymmetric nuclear collisions. For one of the most promising systems currently under investigation, ${}^{96}_{44}{\rm Ru}+{}^{96}_{40}{\rm Zr}$, we investigate the influence of the equation of state and the inelastic in-medium cross section.Comment: 16 pages, 12 figures, submitted to Europ. Phys. J. A Discussion adde

Analysis of flow effects in relativistic heavy-ion collisions within the CBUU approach

We study flow phenomena in relativistic heavy-ion collisions, both in transverse and radial direction, in comparison to experimental data. The collective dynamics of the nucleus-nucleus collision is described within a transport model of the coupled channel BUU type (CBUU). This recently developed version includes all nucleonic resonances up to 1.95 GeV in mass and mean-field potentials both of the Skyrme and momentum dependent MDYI type. We find that heavy resonances play an important role in the description of transverse flow above 1 AGeV incident energy. For radial flow we analyse reaction times and equilibration and extract the parameters $T$ and $\beta$ for temperature and collective flow velocity within different prescriptions. Furthermore, we apply a coalescence model for fragment production and check the mass dependence of the flow signals.Comment: 25 pages, 17 figures, submitted to Europ. Phys. J.

Virtual Institutes: Between Immersion and Communication

In the two expressions "virtual reality" and "virtual community", the term "virtual" has different meanings. A virtual reality is a depiction or, more generally speaking, a sensuous representation of reality that allows - mainly by means of interactivity - to experience various features of reality without actually being in contact with the reality depicted. Therefore, any interactive depiction that is able to imitate reality to such an extent that a high degree of sensory-motor immersion becomes possible is called a virtual reality (Heim 1998, 6f). Since reality is always much more complex than its depiction and full of unpredictable surprises, hardly ever a user has doubts about the difference between the depiction and the thing depicted. Nevertheless, there are good reasons for preferring the imitation to the reality: at least, the imitation is usually not as dangerous as reality sometimes turns out to be. Accordingly, quite different platforms for virtual institutes may be used emphasizing either the immersion aspect or the communication aspect. The decision for a platform depends on the goals pursued with the institute: text-based chat systems allow virtual communities to flourish, single-user VRML scenes convey a highly immersive 3D impression to its users. This is particularly true for virtual institutes realized as a 3D environment, as well as for corresponding virtual communities since 3D environments are adequate for certain tasks only. As an overall framework for the evaluation it is helpful to distinguish three major application areas: research, presentation, and communicative work. The Virtual Institute for Image Science (VIB), which we would like to describe in the following (3) as a case study, is almost exclusively designed for the third task: communicative working. It intends to provide a working space persons can share for joint projects despite being physically separated. Before describing the VIB in more detail we would like to give an overview of virtual institutes between the poles of realistic immersion and of communication in a community (2). The discussion of the case study leads to some more general considerations about the balance virtual institutes must find along that bi-polar dimension (4). In the concluding remarks we focus on the technical tools for virtual communities in 3D presently available

Herbarts Kantkritik und die Idee einer Philosophischen Psychologie. Vortrag, gehalten am Kongress "I confini dell'anima. Filosofia e psicologia da Herbart a Freud" in l'Aquila, 11.-14. Mai 1994. (Deutsche Fassung)

Es wird die These ausgeführt, daß Herbart mit seiner Kantkritik die Grundrichtung der Kantischen Philosophie verfehlte, daß er aber - vielleicht gerade wegen dieses Mißverständnisses - einen Philosophiebegriff entwickelte, der bis heute Aktualität beanspruchen kann

Bildbegriff und Bildwissenschaft

Seit einiger Zeit rückt die Bild-Forschung in den Blickpunkt des öffentlichen wie des wissenschaftlichen Interesses. Unterschiedliche Disziplinen beschäftigen sich mit Teilbereichen der Bildthematik. Kann es gelingen, einen gemeinsamen Theorierahmen zu entwickeln, der ein integratives Forschungsprogramm liefert? Es werden zentrale theoretische Problembestände des Bildgbegriffs skizziert, um sodann für die Auffassung von Bildern als "wahrnehmungsnahe Zeichen" zu plädieren

Photoabsorption on nuclei

We calculate the total photoabsorption cross section on nuclei in the energy range from 300 MeV to 1 GeV within the framework of a semi-classical phase space model. Besides medium modifications like Fermi motion and Pauli blocking we focus on the collision broadening of the involved resonances. The resonance contributions to the elementary cross section are fixed by fits to partial wave amplitudes of pion photoproduction. The cross sections for $N \, R \to N \, N$, needed for the calculation of collision broadening, are obtained by detailed balance from a fit to $N \, N \to N \, N \, \pi$ cross sections. We show that a reasonable collision broadening is not able to explain the experimentally observed disappearance of the $D_{13}(1520)$-resonance in the photoabsorption cross section on nuclei.Comment: 26 pages Latex including 9 postscript figure

MutationDistiller: user-driven identification of pathogenic DNA variants

MutationDistiller is a freely available online tool for user-driven analyses of Whole Exome Sequencing data. It offers a user-friendly interface aimed at clinicians and researchers, who are not necessarily bioinformaticians. MutationDistiller combines Mutation- Taster’s pathogenicity predictions with a phenotypebased approach. Phenotypic information is not limited to symptoms included in the Human Phenotype Ontology (HPO), but may also comprise clinical diagnoses and the suspected mode of inheritance. The search can be restricted to lists of candidate genes (e.g. virtual gene panels) and by tissue-specific gene expression. The inclusion of GeneOntology (GO) and metabolic pathways facilitates the discovery of hitherto unknown disease genes. In a novel approach, we trained MutationDistiller’s HPO-based prioritization on authentic genotype–phenotype sets obtained from ClinVar and found it to match or outcompete current prioritization tools in terms of accuracy. In the output, the program provides a list of potential disease mutations ordered by the likelihood of the affected genes to cause the phenotype. MutationDistiller provides links to gene-related information from various resources. It has been extensively tested by clinicians and their suggestions have been valued in many iterative cycles of revisions. The tool, a comprehensive documentation and examples are freely available at https://www.mutationdistiller.org

Young T Cells Age During a Redirected Anti-Tumor Attack: Chimeric Antigen Receptor-Provided Dual Costimulation is Half the Battle

Adoptive therapy with chimeric antigen receptor (CAR)-redirected T cells showed spectacular efficacy in the treatment of leukemia in recent early phase trials. Patient’s T cells were ex vivo genetically engineered with a CAR, amplified and re-administered to the patient. While T cells mediating the primary response were predominantly of young effector and central memory phenotype, repetitive antigen engagement irreversible triggers T cell maturation leaving late memory cells with the KLRG1(+) CD57(+) CD7(−) CCR7(−) phenotype in the long-term. These cells preferentially accumulate in the periphery, are hypo-responsive upon TCR engagement and prone to activation-induced cell death. A recent report indicates that those T cells can be rescued by CAR provided CD28 and OX40 (CD134) stimulation. We discuss the strategy with respect to prolong the anti-tumor response and to improve the over-all efficacy of adoptive cell therapy

Consequences of revised CLSI and EUCAST guidelines for antibiotic susceptibility patterns of ESBL- and AmpC β-lactamase-producing clinical Enterobacteriaceae isolates

Objectives This study aimed to: (i) analyse the antibiotic susceptibility testing (AST) profiles of extended spectrum β-lactamase (ESBL)- and AmpC β-lactamase-producing clinical Enterobacteriaceae isolates applying EUCAST 2013 AST guidelines; and (ii) evaluate discrepancies in AST profiles according to EUCAST 2010 guidelines, EUCAST 2013 guidelines, CLSI 2009 guidelines and CLSI 2013 guidelines. Methods The 195 ESBL- and/or AmpC β-lactamase-producing Enterobacteriaceae isolates used in this study were systematically characterized by disc diffusion AST interpreted according to the 2013 guidelines of EUCAST and CLSI, the EUCAST 2010 guidelines and the CLSI 2009 guidelines. Results Individual cephalosporin AST patterns according to EUCAST 2013 guidelines were described for individual ESBL and AmpC β-lactamase genotypes. Significant differences in the susceptibility rates of important cephalosporins such as cefepime, ceftazidime and cefotaxime applying EUCAST 2013 and CLSI 2013 AST guidelines were demonstrated for ESBL- and AmpC β-lactamase-producing isolates. Conclusions The confirmation of ESBL and/or AmpC β-lactamase production can support the selection of an adequate antibiotic drug therapy. Despite a harmonized CLSI and EUCAST ‘report as found' strategy for cephalosporins and ESBL-producing isolates, AST interpretation according to the CLSI 2013 and EUCAST 2013 guidelines shows significant differences in susceptibility rates for mainstay cephalosporins such as cefepime, ceftazidime and cefotaxime. Thus, further harmonization of clinical breakpoints is warrante