6,442 research outputs found

    Advantages and challenges in coupling an ideal gas to atomistic models in adaptive resolution simulations

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    In adaptive resolution simulations, molecular fluids are modeled employing different levels of resolution in different subregions of the system. When traveling from one region to the other, particles change their resolution on the fly. One of the main advantages of such approaches is the computational efficiency gained in the coarse-grained region. In this respect the best coarse-grained system to employ in the low resolution region would be the ideal gas, making intermolecular force calculations in the coarse-grained subdomain redundant. In this case, however, a smooth coupling is challenging due to the high energetic imbalance between typical liquids and a system of non-interacting particles. In the present work, we investigate this approach, using as a test case the most biologically relevant fluid, water. We demonstrate that a successful coupling of water to the ideal gas can be achieved with current adaptive resolution methods, and discuss the issues that remain to be addressed

    Fachspezifisches Unterrichtscoaching im Praktikum: Eine quasi-experimentelle Interventionsstudie

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    Zusammenfassung: Wiederholt wurde gezeigt, dass Unterrichtspraktika von Lehramtsstudierenden sehr geschätzt werden. Allerdings wissen wir wenig über die Wirkung unterschiedlicher Unterstützungsformen in Praktika auf das Lernen zukünftiger Lehrpersonen. Ein Modell zur Förderung von Praktikanten ist das fachspezifische Unterrichtscoaching. In einer quasi-experimentellen Interventionsstudie wurde dessen Wirksamkeit basierend auf Fragebogen, Videoaufzeichnungen und Interviews mit Dyaden von Praxislehrpersonen und ihren Praktikanten untersucht. Ergebnisse der Studie zeigen, dass in fachspezifischem Unterrichtscoaching weitergebildete Praxislehrpersonen (Interventionsgruppe, NIG = 16) wesentliche Elemente dieses Modells in ihr Handlungsrepertoire aufnahmen. Ihre Unterstützungspraxis unterscheidet sich signifikant von jener der Kontrollgruppe (NKG = 16), welche die Praktikanten auf traditionelle Weise unterstützen. Indikatoren für Lernen im Kontext von Unterrichtsbesprechungen belegen weiter, dass die Praktikanten der Interventionsgruppe signifikant mehr Lernerträge erzielten als die traditionell unterstützten Praktikanten. Auch die anhand von Videoaufnahmen vorgenommene Einschätzung der Unterrichtsqualität fiel für die Interventionsgruppe signifikant besser aus als für die Kontrollgrupp

    Piercing the Fog: Intelligence and Army Air Forces Operations in World War II

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    Quantum Holography

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    We propose to make use of quantum entanglement for extracting holographic information about a remote 3-D object in a confined space which light enters, but from which it cannot escape. Light scattered from the object is detected in this confined space entirely without the benefit of spatial resolution. Quantum holography offers this possibility by virtue of the fourth-order quantum coherence inherent in entangled beams.Comment: 7 pages, submitted to Optics Expres

    Muscle glycogen recovery after exercise measured by13C-magnetic resonance spectroscopy in humans: effect of nutritional solutions

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    The rate of glycogen resynthesis in human skeletal muscle after glycogen-depleting exercise is known to depend on carbohydrate intake and is reported to reach a platean after an adequate amount of carbohydrate (CHO) consumption. Efforts to maximize the rate of glycogen storage by changing the type and form of CHO, as well as by adding proteins or lipids have yielded inconsistent results. The objective of this study was to assess whether isocaloric addition of proteins and arginine to a CHO diet in the first 4 h after an endurance exercise would increase the rate of glycogen synthesis. The CHO solution, given twice at a 2 h interval according to earlier optimized protocols, contained 1.7 g CHO kgbody weight. The effects of this solution were compared to those of an isocaloric solution containing 1.2 g CHO/kgbody weight plus 0.5 g protein/kgbody weight (including 5 g arginine). Glycogen was measured in quadriceps muscle in vivo with natural abundance13C-magnetic resonance spectroscopy before exercise and twice after exercise, before and at the end of a 4-h period following the intake of one of the solutions. Eight subjects took part in a randomized cross-over trial separated by at least 1 week. Glycogen synthesis was found to be significantly increased with both regimes compared to a zero-caloric placebo diet, but no significant difference in glycogen resynthesis was found between the CHO-only diet and the one supplemented by proteins and arginine. It is estimated that significance would have been reached for an increase of 34%, while the effectively measured synthesis rates only differed by 5

    Does migrant background predict to what extent colorectal cancer patients want to be informed about their life expectancy? – a cross-sectional analysis

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    Background: Although migrant health is a topic of interest across Europe and although health care services in Germany consider migrant health issues, people with a migrant background often experience difficulties regarding health care provision. The prevalence of various cancers among migrants is lower relative to non-migrants although this equalizes with increasing duration of residence. There are documented differences in health behavior and disease-coping strategies between migrants and non-migrants, but data are scarce on this subject. This analysis investigates the extent of information migrant and non-migrant colorectal cancer (CRC) patients in Germany want about their life expectancy and the level of trust they have in their treating physician. Method: Data from 522 CRC patients were collected through a self-reported questionnaire. Migrant background was determined by the patients’ and/or their parents’ birthplace. Bivariate analyses were applied to determine the differences between migrants and non-migrants. A multivariate analysis was used to measure the effect of migration background, demographics, and cancer stage and treatment on the preferred extent of information about life expectancy and trust in their treating physician. Results: There were no significant differences regarding demographics or cancer stage and treatment between migrant and non-migrant CRC patients. Having a migrant background had no influence on the level of trust in the treating physician, but migrants preferred to be less informed about their life expectancy than non-migrants (21.4% vs. 13.4%, p = 0.04). The multivariate analysis showed that men (aOR = 2.102, CI: 1.123–3.932) and patients with a non-migrant background (aOR = 5.03, CI: 1.02–24.73) preferred receiving information about the approximate value of their life expectancy, rather than receiving no information. Conclusion: The study found more similarities than discrepancies between migrant and non-migrant CRC patients regarding demographic factors and stage of disease and treatment, which may be a consequence of an increasingly homogeneous cross-cultural society. However, cultural differences between the minority and host population remain and should always be taken into account in daily clinical practice and in the communication skills training of health care professionals. The study also indicates that recording migration background into health registers would facilitate migrant-sensitive research.publishedVersio

    Assessing New Methods of Integrated Pest Management for Apple Orchards in the Midwest

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    Producing apples in the Midwest requires intensive, chemically based pest management systems in order to bring high-quality, fresh market apples to consumers. A combination of rising costs, pest resistance, and new legislation has caused existing systems of apple pest management to become ineffective or to fall out of favor with growers. Because of this, new methods of pest control were developed to combat the ever present problems in apple production. These new methods must meet a number of criteria: sufficient pest control must be achieved; the innovative tactics must be safer for applicators, the environment, and consumers; and also must be economically feasible or they are not likely to be adopted by growers

    Удалители для асфальтосмолопарафиновых отложений месторождений Западного Казахстана

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    Signal transducers and activators of transcriptions (STAT) are key mediators of cytokine signaling. Moreover, these transcription factors play a crucial role in oncogenic signaling where inappropriate and sustained activation of STATs, especially STAT3, is a trait of many different cancers and their derived cell lines. Constitutively active STAT3 has been reported to prevent programmed cell death and enhance cell proliferation, whereas the disruption of STAT3 signaling can inhibit tumor growth. The physiologic activation of STAT3 by cytokines has been well established; however, little is known about altered, stimulation-independent STAT3 activation. Here, we show that, in most but not all melanoma cell lines, STAT3 phosphorylation increased substantially with cell density and that this STAT3 was able to bind to DNA and to activate transcription. Inhibitor studies showed that the cell density-dependent STAT3 activation relies on Janus kinases (JAK) rather than Src kinases. Using a specific JAK inhibitor, sustained STAT3 activation was completely abrogated in all tested melanoma lines, whereas inhibition of Src or mitogen-activated protein kinase/extracellular signal-regulated kinase kinase 1/2 had no effect on constitutively tyrosine-phosphorylated STAT3 levels. Although STAT3 activation was completely blocked with JAK inhibitor I and to a lesser extent with the common JAK inhibitor AG490, only the latter compound markedly decreased proliferation and induced apoptosis. Taken together, variations in cell density can profoundly modify the extent of JAK-mediated persistent STAT3 phosphorylation; however, STAT3 activation was not sufficient to provide critical growth and survival signals in melanoma cell lines
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