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921.
Pregnancy and associated pre‐eclampsia carry a high maternal risk in hemodialysis patients, yet no guidelines on how to monitor these patients' cardiovascular function exist. A 34‐year‐old hemodialysis patient presented with peripartum cardiomyopathy after a late second trimester miscarriage. On cardiac magnetic resonance imaging, diagnostic features of left ventricular noncompaction were apparent. Yet, histological and gene panel analyses remained negative. Upon stringent dry weight control and pharmacological heart failure therapy, the pathological changes showed complete regression. As pregnant hemodialysis patients have an excessively increased risk for pre‐eclampsia‐related cardiac disease, thorough screening appears valuable in these patients.  相似文献   
922.
Atomistic simulations of fracture in L10 TiAl were carried out using embedded atom method (EAM) interatomic potentials and molecular statics. We studied the behavior of semi-infinite cracks under mode I loading in different orientations of the crack front and plane. For the orientation, we observed dislocation emission involving the formation of superlattice intrinsic stacking fault (SISF). For the [001](110) orientation, we observed the emission of ordinary 1/2[110] edge dislocations that were highly mobile and had a compact core. We found that cracks with [001](100) orientation cleaved near the Griffith value of loading in a purely brittle manner. Similar behavior was observed for cracks with orientation. This article is based on a presentation made in the symposium “Fundamentals of Gamma Titanium Aluminides”, presented at the TMS Annual Meeting, February 10–12, 1997, Orlando, Florida, under the auspices of the ASM/MSD Flow & Fracture and Phase Transformations Committees.  相似文献   
923.
Atomistic simulations of fracture in L10 TiA1 were carried out using embedded atom method (EAM) interatomic potentials and molecular statics. We studied the behavior of semi-infinite cracks under mode I loading in different orientations of the crack front and plane. For the (111) orientation, we observed dislocation emission involving the formation of superlattice intrinsic stacking fault (SISF). For the [001](110) orientation, we observed the emission of ordinary 1/2[110] edge dislocations that were highly mobile and had a compact core. We found that cracks with [001](100) orientation cleaved near the Griffith value of loading in a purely brittle manner. Similar behavior was observed for cracks with (100) orientation. This article is based on a presentation made in the symposium “Fundamentals of Gamma Titanium Aluminides,” presented at the TMS Annual Meeting, February 10–12, 1997, Orlando, Florida, under the auspices of the ASM/MSD Flow & Fracture and Phase Transformations Committees.  相似文献   
924.
A two-grid scheme to approximate the evolutionary Navier–Stokes equations is introduced and analyzed. A standard mixed finite element approximation is first obtained over a coarse mesh of size H at any positive time \(T>0\). Then, the approximation is postprocessed by means of solving a steady problem based on one step of a Newton iteration over a finer mesh of size \(h<H\). The method increases the rate of convergence of the standard Galerkin method in one unit in terms of H and equals the rate of convergence of the standard Galerkin method over the fine mesh h. However, the computational cost is essentially the cost of approaching the Navier–Stokes equations with the plain Galerkin method over the coarse mesh of size H since the cost of solving one single steady problem is negligible compared with the cost of computing the Galerkin approximation over the full time interval (0, T]. For the analysis we take into account the loss of regularity at initial time of the solution of the Navier–Stokes equations in the absence of nonlocal compatibility conditions. Some numerical experiments are shown.  相似文献   
925.
For hazard zoning or planning of control measures the identification of the hydrogeomorphic key process is an important step to determine the recurrent design event. The present methodology for the identification of potential hydrogeomorphic key processes is a practicable tool for experts assessing homogeneous sections of running waters (torrents, mountain streams and low-lying rivers) by means of certain parameters. Filling in the developed matrix from your desk and reviewing the results with field surveys on site, the potential key process is rapidly identified for each homogeneous area, as the evaluation of 12 sample streams in Carinthia shows. Further on this method is a useful tool concerning sediment management concepts according to the National Watercourse Development Plan or financial supporting of control measures at stakeholder waters at the field of competence of the Austrian Flood Control Management.  相似文献   
926.
927.
In this paper we describe software which could be used as a decision support tool for decision makers in competitive electricity markets. The tool is based on the behavior of the competitors in the market, thus many different parameters around them are considered and, additionally, many different scenarios can be used. The possible results are obtained by simulation. Two modes are implemented; one to simulate the functioning of a competitive electricity market and the other, called manual, to evaluate the success of particular strategies by a user. Finally, some computational experience is reported to validate the simulation model.  相似文献   
928.
The purpose of this study was to consider the efficacy and popularity of “Virtual Lectures” (text-based, structured electronic courseware with information presented in manageable “chunks”, interaction and multimedia) and “e-Lectures” (on-screen synchrony of PowerPoint slides and recorded voice) as alternatives to traditional lectures. We considered how three modes of delivery compare when increasingly deeper forms of learning are assessed and also student reaction to electronic delivery. Fifty-eight students in three groups took three topics of a human genetics module, one in each delivery style. Results indicated no overall greater efficacy of either delivery style when all question types were taken into account but significantly different delivery-specific results depending on which level of Bloom’s taxonomy was assessed. That is, overall, questions assessing knowledge consistently achieved the highest marks followed by analysis, comprehension, evaluation and application. Students receiving traditional lectures scored significantly lower marks for comprehension questions. Students receiving Virtual Lectures scored high for knowledge, comprehension and application but significantly lower for analysis and evaluation questions. The e-Lectures scored high for knowledge questions and were the median for all question types except application. Questionnaire analysis revealed a preference for traditional lectures over computer-based but nevertheless an appreciation of the advantages offered by them.  相似文献   
929.
The next generation of sensors requires a simple yet compact lab on chip-based precise optical detection mechanism where data interpretation can be achieved with minimum effort. Hereby, cost-efficient strategies of manufacturing both propagating surface plasmon polariton (SPP) and localized surface plasmon resonance (LSPR) sensors on flexible platforms are explored via mechanical instabilities and oblique-angled metal evaporation. Centimeter scaled dielectric grating structures produced by plasma oxidation of pre-stressed polydimethylsiloxane film have comprised the substrates, thus imparting inherent flexibility. Subsequently, both continuous and discontinuous 1D-metallic lattices are obtained via vapor deposition of gold at different angles. The optical isotropy (gold surface-grating) and anisotropy (gold edge-grating) are distinctly observed as a difference between forward and backward diffraction efficiencies, backed by analytical correlation to the observed orders. Supported with electromagnetic modeling, the SPP and LSPR excitations are experimentally characterized under reflectance and transmittance measurements, along with a demonstration of their sensing capabilities. The LSPR supported flexible sensor provides superiority in terms of sensitivity, which is investigated under mechanical deformations to exhibit consistency of the resonant wavelength. Such consistency is strategically unraveled via “finite element method” based approaches, thus providing a new paradigm of cost-efficient, large-scaled flexible sensors.  相似文献   
930.
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