Cisplatin-Based Chemotherapy for Pulmonary Metastasized Germ Cell Tumors of the Testis - Be Aware of Acute Respiratory Distress Syndrome

Background: Cisplatin-based combination chemotherapy is regarded as standard of care for patients with advanced germ cell tumors. In patients with lung metastases and a high tumor load, an association between induction chemotherapy and the development of a `tumor-associated' acute respiratory distress syndrome (ARDS) has been hypothesized. Case Report: We report the clinical course of a 19-year-old patient who rapidly developed fatal ARDS during the first cycle of chemotherapy using the PEI regimen (cisplatin, etoposide and ifosfamide) for a metastasized (lung, liver, lymph nodes) germ cell tumor of the testis. Conclusion: Further clinical research in order to better define risk factors for developing ARDS in this patient population as well as novel strategies for the prevention and treatment of ARDS in those patients are necessary

Local Shielding Gas Supply in Remote Laser Beam Welding

The use of shielding gases in laser beam welding is of particular interest for materials interacting with ambient oxygen, e.g., copper, titanium or high-alloy steels. These materials are often processed by remote laser beam welding where short welds (e.g., up to 40 mm seam length) are commonly used. Such setups prevent gas nozzles from being carried along on the optics due to the scanner application and a small area needs to be served locally with inert gas. The article provides systematic investigations into the interaction of laser beam processes and parameters of inert gas supply based on a modular flat jet nozzle. Based on the characterization of the developed nozzle by means of high-speed Schlieren imaging and constant temperature anemometry, investigations with heat conduction welding and deep penetration welding were performed. Bead-on-plate welds were carried out on stainless steel AISI 304 for this purpose using a disc laser and a remote welding system. Argon was used as shielding gas. The interaction between Reynolds number, geometrical parameters and welding/flow direction was considered. The findings were proved by transferring the results to a complex weld seam geometry (C-shape)

Low-dimensional spike rate models derived from networks of adaptive integrate-and-fire neurons : comparison and implementation

The spiking activity of single neurons can be well described by a nonlinear integrate-and-fire model that includes somatic adaptation. When exposed to fluctuating inputs sparsely coupled populations of these model neurons exhibit stochastic collective dynamics that can be effectively characterized using the Fokker-Planck equation. This approach, however, leads to a model with an infinite-dimensional state space and non-standard boundary conditions. Here we derive from that description four simple models for the spike rate dynamics in terms of low-dimensional ordinary differential equations using two different reduction techniques: one uses the spectral decomposition of the Fokker-Planck operator, the other is based on a cascade of two linear filters and a nonlinearity, which are determined from the Fokker-Planck equation and semi-analytically approximated. We evaluate the reduced models for a wide range of biologically plausible input statistics and find that both approximation approaches lead to spike rate models that accurately reproduce the spiking behavior of the underlying adaptive integrate-and-fire population. Particularly the cascade-based models are overall most accurate and robust, especially in the sensitive region of rapidly changing input. For the mean-driven regime, when input fluctuations are not too strong and fast, however, the best performing model is based on the spectral decomposition. The low-dimensional models also well reproduce stable oscillatory spike rate dynamics that are generated either by recurrent synaptic excitation and neuronal adaptation or through delayed inhibitory synaptic feedback. The computational demands of the reduced models are very low but the implementation complexity differs between the different model variants. Therefore we have made available implementations that allow to numerically integrate the low-dimensional spike rate models as well as the Fokker-Planck partial differential equation in efficient ways for arbitrary model parametrizations as open source software. The derived spike rate descriptions retain a direct link to the properties of single neurons, allow for convenient mathematical analyses of network states, and are well suited for application in neural mass/mean-field based brain network models.Characterizing the dynamics of biophysically modeled, large neuronal networks usually involves extensive numerical simulations. As an alternative to this expensive procedure we propose efficient models that describe the network activity in terms of a few ordinary differential equations. These systems are simple to solve and allow for convenient investigations of asynchronous, oscillatory or chaotic network states because linear stability analyses and powerful related methods are readily applicable. We build upon two research lines on which substantial efforts have been exerted in the last two decades: (i) the development of single neuron models of reduced complexity that can accurately reproduce a large repertoire of observed neuronal behavior, and (ii) different approaches to approximate the Fokker-Planck equation that represents the collective dynamics of large neuronal networks. We combine these advances and extend recent approximation methods of the latter kind to obtain spike rate models that surprisingly well reproduce the macroscopic dynamics of the underlying neuronal network. At the same time the microscopic properties are retained through the single neuron model parameters. To enable a fast adoption we have released an efficient Python implementation as open source software under a free license

Der Fachtext als komplexes Wissenssystem. Ein interdisziplinäres Konzept.

The increasing interest of the current LSP research in cognitive science has led to a broadening and deepening of its subject-matter, now including the communicativecognitive procedures of information transfer and mental processing of information at all levels of LSP communication. As a consequence of this paradigmatic change, LSP research has been confronted with the comprehensive analysis of knowledge systems being transformed by encoding processes into language elements and relations at the textual level (Baumann 1992, 146-149). A great number of LSP text analyses have demonstrated that LSP is a regular part of the process of specialist thinking (Baumann 1994). Undoubtedly, this insight has paved the way for a methodologically promising interdisciplinary analysis of the interrelation between language and thinking. In this context the communicative aspect of LSP is to be considered as the result of multiple, highly interactive knowledge systems. Because knowledge systems as the initial and final part of LSP communication cannot be observed directly, LSP research and cognitive science together must try to re-construct knowledge components and strategies in various fields of specialist actions. When dealing with these crucial problems it becomes apparent that a typology of knowledge is an unavoidable precondition for studying the language realisation of knowledge structures. From the methodological and methodical point of view it seems to be promising to include all those structural and functional elements and relations into this theory which play - on the various hierarchical levels of communication - an important role in text and information processing. This work is based upon an inductive-empirical analysis of English and German LSP texts - all belonging to one and the same text form, article (articles from an encyclopedia, scientific articles, popular-science articles) - from the fields of medicine and linguistics in English and German. Our interdisciplinary approach to the LSP text corpus is based upon descriptive, functional, structural, comparative, statistical and other methods. Finally, we have found that ten different, hierarchically working types of knowledge do determine LSP communication: i.e. the intercultural, social and situational, metacognitive, specialized, functional, textual, syntactical, stylistic and semantic

Reações de compostos carbonilicos com acido barbiturico e 1,3-dimetilbarbiturico

Dissertação (mestrado) - Universidade Federal de Santa Catarina. Centro de Ciencias Fisicas e MatematicasAs reações envolvendo o ataque nucleofílico de uma base nitrogenada sobre o grupo carbonila como centro eletrofílico, têm grande interesse do ponto de vista do estudo do mecanismo de reações como também bioquímico, pois uma boa parte das reações enzimáticas se realizam por esses mecanismos. Com o objetivo de comparar e ampliar o conhecimento desse tipo de reações foram estudadas as reações de íons barbiturato e 1,3-dimetilbarbiturato com o o- e p-nitrobenzaldeido e 2,4-dinitrobenzaldeido. O comportamento das reações mostra-se semelhante ao das bases nitrogenadas com compostos carbonílicos. As reações do ácido barbitúrico com o- e p-nitrobenzaldeído apresentam um perfil de log k2 (k2 = constante de velocidade de segunda ordem) vs pH do tipo A (segundo Sayer) modificado. As reações entre o ácido barbitúrico 1,3-dimetilbarbitúrico com 2,4-dinitrobenzaldeído mostraram um perfil de log k2 vs pH de tipo B. Este perfil deve apresentar uma região de pH onde ocorre somente a transferência de um próton do hidrônio a um intermediário da reação. Os gráficos de Brönsted não mostraram uma quebra na linearidade (Curva de Eigen). No entanto, a dependência da velocidade de reação com a viscosidade do solvente (água/glicerol 50/50 v/v), o grande efeito isotópico determinado (kD2O / kD2O = 4,20) e o ponto experimental correspondente ao hidrônio, indicam que esta região corresponde a uma transferência de próton controlada por difusão de hidrônio para um intermediário T, como etapa determinante da velocidade

German Psychiatrists’ Observation and Interpretation of Religiosity/Spirituality

The purpose of this study was to explore how contemporary German psychiatrists think about religiosity/spirituality (ReS) in regard to their therapies. We conducted an anonymous survey among the clinical staff of psychiatry and psychotherapy departments in German university hospitals and faith-based clinics in the same cities. Two main instruments were used, the Duke University Religion Index (DUREL) and the questionnaire from Curlin et al. “Religion and Spirituality in Medicine: Physicians’ Perspectives.” A total of 123 psychiatrists participated in this survey. However, due to incomplete responses, only 99 questionnaires from psychiatrists were analyzed. Results show that German psychiatrists positively experience the influence of ReS on patients’ mental health. Psychiatrists’ own ReS significantly influenced their interpretation of the effect of ReS on psychiatric patients as well as their attitude toward ReS in the clinical setting. The more religious psychiatrists are, the more they tend to observe a positive influence of ReS on mental health. In light of these results, psychiatrists should be aware of their own religious/spiritual characteristics and also reconsider their assumptions about professional neutrality and value openness. Furthermore, training programs on religious/spiritual issues and effective teamwork with chaplains are recommended