Non-newtonian viscous elongation and shear fluid model based on optimal triple tensor decomposition

The modeling of the distinct non-Newtonian fluid properties is an essential prerequisite for the computational simulation of associated flow fields. In particular, some non-Newtonian fluids reveal strong diverse viscosity response behaviours to pure elongational and simple shearing flows. Therefore, it is necessary to be able to distinguish between these flow types even in complex flow configuration. Unfortunately flow types are naturally mixed and this distinction becomes quite difficult. Only in a Lagrangian framework the tracking of the Lagrangian fluid element deformation allows an accurate strain related deformation type assignment. However, most CFD approaches prefer the Eulerian framework accepting the loss of the natural flow path alignment of the moving fluid particles. Consequently shear and elongation rates are barely separable without particular assignment methods. In this work a tensor decomposition method from vortex dynamics is discussed which allows to distinguish between these flow types. In vortex dynamics the problem occurred to separate shearing from purely rotational flows because different hydro- and aerodynamic flow phenomena are caused by shear and vortex related flow types. Thereto, various methods were proposed, among others the optimal triple tensor decomposition method which is able to separate vortical from shearing flows but also, after some modification, elongational from shearing flows. This tensor decomposition is now used to calculate elongation and shearing rates as input variables into non-Newtonian fluid models for the calculation of the local elongational and shear viscosity. The application case is a cross slot channel flow often used as reference. In this numerical simulation study the impact of the elongation rate modeling on the contraction flow topology is shown and discussed. It is shown that the modeling of different viscous elongational and shear-thinning affects the resulting flow significantly &nbsp

Inhibition of diacylglycerol–sensitive TRPC channels by synthetic and natural steroids

TRPC channels are a family of nonselective cation channels that regulate ion homeostasis and intracellular Ca2+ signaling in numerous cell types. Important physiological functions such as vasoregulation, neuronal growth, and pheromone recognition have been assigned to this class of ion channels. Despite their physiological relevance, few selective pharmacological tools are available to study TRPC channel function. We, therefore, screened a selection of pharmacologically active compounds for TRPC modulating activity. We found that the synthetic gestagen norgestimate inhibited diacylglycerol-sensitive TRPC3 and TRPC6 with IC50s of 3–5 µM, while half-maximal inhibition of TRPC5 required significantly higher compound concentrations (>10 µM). Norgestimate blocked TRPC-mediated vasopressin-induced cation currents in A7r5 smooth muscle cells and caused vasorelaxation of isolated rat aorta, indicating that norgestimate could be an interesting tool for the investigation of TRP channel function in native cells and tissues. The steroid hormone progesterone, which is structurally related to norgestimate, also inhibited TRPC channel activity with IC50s ranging from 6 to 18 µM but showed little subtype selectivity. Thus, TRPC channel inhibition by high gestational levels of progesterone may contribute to the physiological decrease of uterine contractility and immunosuppression during pregnancy

Layer-by-layer biofabrication of coronary covered stents with clickable elastin-like recombinamers

Producción CientíficaCoronary artery disease is the leading cause of death around the world. Endovascular stenting is the preferred treatment option to restore blood flow in the coronary arteries due to the lower perioperative morbidity when compared with more invasive treatment options. However, stent failure is still a major clinical problem, and further technological solutions are required to improve the performance of current stents. Here, we developed coronary stents covered with elastin-like recombinamers (ELRs) by exploiting a layer-by-layer technique combined with catalyst-free click chemistry. The resulting ELR-covered stents were intact after an in vitro simulated implantation procedure by balloon dilatation, which evidenced the elastic performance of the membrane. Additionally, the stents were mechanically stable under high flow conditions, which is in agreement with the covalent and stable nature of the click chemistry crosslinking strategy exploited during the ELR-membrane manufacturing and the successful embedding of the stent. Minimal platelet adhesion was detected after blood exposure in a Chandler loop as shown by scanning electron microscopy. The seeding of human endothelial progenitor cells (EPCs) on the ELR-membranes resulted in a confluent endothelial layer. These results prove the potential of this strategy to develop an advanced generation of coronary stents, with a stable and bioactive elastin-like membrane to exclude the atherosclerotic plaque from the blood stream or to seal coronary perforations and aneurysms, while providing a luminal surface with minimal platelet adhesion and favouring endothelialization.German federal and state governments (project StUpPD_330-18)Ministerio de Economía, Industria y Competitividad (projects PCIN-2015-010 / MAT2016-78903-R)Junta de Castilla y León (project VA317P18

Toxizität radioaktiver Abfallstoffe aus dem Betrieb von Kernreaktoren im Vergleich mit der Radiotoxizität natürlicher Uranvorkommen am Beispiel der BRD

For a supposed population of nuclear reactors in the FRG during the next 5 decades, the hazard potential of the produced nuclear waste of different fuel cycles using Uranium and Plutonium is calculated by use of the computercode ORIGEN-EXJÜL. The consequences concerning the hazard potential resulting from these strategies are investigated using the radioactivity concentration guides as given in the US-Code of Federal Regulations. In addition, more restrictive values in view of ingestion for some heavy metal isotopes are applied and a comparison of the impacts is made. With regard to the acceptibility of disposing the nuclear waste, its hazard potential is compared with the ingestion hazard, of the natural uranium content in the soil of the FRG

Правовой статус персональных данных работников

В статье рассматривается проблема сохранения конфиденциальности персональных данных работников. Целью является выяснение специфики понятия персональных данных работника, правовых основ обработки таких данных и виды юридической ответственности за их разглашение. Проведен сравнительный анализ норм права, содержащих требования по работе с персональными данными. Установлен круг информации, относящейся к категории персональных данных. Рассмотрены составы правонарушений в области сохранения персональных данных и меры ответственности за их совершение. Сделаны выводы о том, что относит законодатель к персональным данным работника и информации, относящейся к личной жизни человека. Актуальность данного исследования бесспорна, так как в повседневной жизни все субъекты используют информацию, перерабатывают ее и распространяют. В то же время крайне низок уровень осведомленности о правовом регулировании использования этой информации и о юридической ответственности за нарушение этих норм

Policy, competence and participation: empirical evidence for a multilevel health promotion model

This paper uses data from a European health promotion evaluation study (MAREPS) to empirically test some fundamental assumptions of health promotion theory. Analysis shows that both the competence of individual actors and the opportunities provided for by health-promoting policies are significant predictors of participation in health promotion action. It also demonstrates effects of health promotion values on such action. Moreover, people's perception of their own political efficacy, e.g. their influence on community decisions that effect their health, turns out to be a significant predictor of self-rated health. In conclusion, the paper encourages further research to investigate the effectiveness of health-promoting policy strategies within a multilevel health promotion framework. As the present results indicate, effective health-promoting policies may create opportunities that enable individuals and communities to increase control over the determinants of health, and thereby improve their healt

Frequency of Microsatellite Instability in Unselected Sebaceous Gland Neoplasias and Hyperplasias

Sebaceous gland neoplasias are the cutaneous manifestation of the Muir–Torre syndrome, which is known to be a phenotypical variant of hereditary nonpolyposis colorectal cancer. Both hereditary nonpolyposis colorectal cancer and Muir–Torre syndrome are caused by inherited DNA mismatch repair defects. As a prominent molecular genetic feature, all tumors associated with a DNA mismatch repair defect exhibit high microsatellite instability. So far, the frequency of DNA mismatch repair defects in patients selected solely on the basis of a sebaceous gland tumor has never been determined. In order to estimate this frequency, we assessed microsatellite instability with up to 10 microsatellite markers in a newly collected unselected series of 25 sebaceous gland neoplasias (six sebaceous adenomas, 16 sebaceous epitheliomas, three sebaceous carcinomas) in comparison to 32 sebaceous gland hyperplasias from unrelated patients. As many as 15 of the 25 sebaceous gland neoplasias (60%), but only one of the 32 sebaceous gland hyperplasias (3%), exhibited high microsatellite instability. Thus, in our study, the majority of patients with a sebaceous gland neoplasia in contrast to patients with a sebaceous gland hyperplasia are highly suspicious for an inherited DNA mismatch repair defect. On the basis of the subsequently collected tumor histories, nine of the 15 patients with a high microsatellite unstable sebaceous gland neoplasia were identified to have Muir–Torre syndrome. In none of these cases, however, were the clinical Amsterdam criteria for diagnosing hereditary nonpolyposis colorectal cancer fulfilled. In the sebaceous tumors of the remaining six patients, high microsatellite instability was an incidental finding. In two of these six patients, single relatives were known to be affected with internal cancer; however, their family histories were not suggestive of Muir–Torre syndrome or hereditary nonpolyposis colorectal cancer. In comparison with microsatellite instability screening studies in a variety of other randomly selected tumors, our study identifies sebaceous gland neoplasias as tumors with the highest frequency of high microsatellite instability reported so far, whereas sebaceous gland hyperplasia rarely exhibits high microsatellite instability. Therefore, screening for microsatellite instability in sebaceous gland neoplasias will be of great value in the detection of an inherited DNA mismatch repair defect, which predisposes to various types of internal cancers

Macroporous click-elastin-like hydrogels for tissue engineering applications

Producción CientíficaElastin is a key extracellular matrix (ECM) protein that imparts functional elasticity to tissues and therefore an attractive candidate for bioengineering materials. Genetically engineered elastin-like recombinamers (ELRs) maintain inherent properties of the natural elastin (e.g. elastic behavior, bioactivity, low thrombogenicity, inverse temperature transition) while featuring precisely controlled composition, the possibility for biofunctionalization and non-animal origin. Recently the chemical modification of ELRs to enable their crosslinking via a catalyst-free click chemistry reaction, has further widened their applicability for tissue engineering. Despite these outstanding properties, the generation of macroporous click-ELR scaffolds with controlled, interconnected porosity has remained elusive so far. This significantly limits the potential of these materials as the porosity has a crucial role on cell infiltration, proliferation and ECM formation. In this study we propose a strategy to overcome this issue by adapting the salt leaching/gas foaming technique to click-ELRs. As result, macroporous hydrogels with tuned pore size and mechanical properties in the range of many native tissues were reproducibly obtained as demonstrated by rheological measurements and quantitative analysis of fluorescence, scanning electron and two-photon microscopy images. Additionally, the appropriate size and interconnectivity of the pores enabled smooth muscle cells to migrate into the click-ELR scaffolds and deposit extracellular matrix. The macroporous structure together with the elastic performance and bioactive character of ELRs, the specificity and non-toxic character of the catalyst-free click-chemistry reaction, make these scaffolds promising candidates for applications in tissue regeneration. This work expands the potential use of ELRs and click chemistry systems in general in different biomedical fields.Ministerio de Economía, Industria y Competitividad (Projects MAT2013-42473-R, MAT2015-68901-R, MAT2016- 78903-R)Junta de Castilla y León (programa de apoyo a proyectos de investigación - Ref. VA313U14, VA015U16 y PCIN-2015-010)gobierno federal y estatal de Alemania en el marco del Programa de Posición Rotacional i³tm (2014-R4-01) y del Programa START de la Facultad de Medicina de la Universidad de Aachen (proyecto nº 691713),el centro de imágenes del Centro Interdisciplinario de Investigación Clínica (IZKF) de la Facultad de Medicina de la Universidad de Aache

Probleme der Stichprobenziehung und -konstruktion bei Telefon-Surveys

'Es werden Probleme hinsichtlich folgender Zielsetzungen bei Stichprobenplänen für Telefon-Surveys diskutiert: (1) Ziehnung von regional begrenzten Stichproben (Bundesländer, Regierungsbezirke, Landkreise); (2) Berücksichtigung nicht-gelisteter Telefonnummern durch die Verwendung von 'Randomized-Last-Digit' - (RLD-) Nummern. Mögliche Lösungen werden am konkreten Beispiel der Ziehung einer Zufallsstichprobe für den Freistaat Sachsen erörtert.' (Autorenreferat)'This article focuses on the problems associated with pursuing: (1) selection of regionally restricted random samples (states -Bundesländer-, administrative districts -Regierungsbezirke, Landkreise-); (2) consideration of unlisted telephone numbers using 'randomized last digit'- (RLD-) numbers. Also discussed are some possible solutions to these problems are suggested by an actual random sample selection for the State of Saxony.' (author's abstract)