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61.
62.
Ninety-two wines from the southernmost wine-producing region in Hungary (Villány) were analyzed for their polyphenolic content by high performance liquid chromatography (HPLC). Our results show that wine variety or vintage year could not be distinguished based on polyphenol content, but winery origin could be. Resveratrol concentration is mainly dependent on variety and vintage year. The “human factor” (i.e., winemaking style and technology) seems to be more decisive for the polyphenolic composition of red wines than other factors, such as variety and vintage year.  相似文献   
63.
In this article, we investigated the thermoformability of poly(lactic acid) (PLA) films with various D -Lactide contents and therefore different crystallization properties, performing tensile and ball burst tests at various temperatures and testing rates. We found that the behavior of the PLA films tested above the glass transition temperature significantly differs due to the difference in D -Lactide content, and thus crystallinity. During tensile testing, elevated temperatures and mechanical stress caused the crystallization temperature to decrease and thus highly induced crystallization. At the same time, as testing speed was increased, the ability of the polymer to crystallize decreased. In ball burst tests, the PLA films crystallized more than during tensile testing. We described the differences found between tensile testing and ball burst testing, which latter better represents the conditions of thermoforming through inducing biaxial deformation.  相似文献   
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Hemostasis disorder in patients with end-stage renal disease (ESRD) is frequently associated with bleeding diathesis but it may also manifest in thrombotic complications. Analysis of individual coagulation and fibrinolytic factors may shed light on the background of this paradox situation. Here we explored components essential for fibrin formation/stabilization in ESRD patients being on maintenance hemodiafiltration (HDF) or hemodialysis (HD). Pre-dialysis fibrinogen, factor XIII (FXIII) antigen concentrations and FXIII activity were elevated, while α2-plasmin inhibitor (α2PI) activity decreased. The inflammatory status, as characterized by C-reactive protein (CRP) was a key determinant of fibrinogen concentration, but not of FXIII and α2PI levels. During a 4-h course of HDF or HD, fibrinogen concentration and FXIII levels gradually elevated. When compensated for the change in plasma water, i.e., normalized for plasma albumin concentration, only FXIII elevation remained significant. There was no difference between HDF and HD treatments. Individual HDF treatment did not influence α2PI activity, however after normalization it decreased significantly. HD treatment had a different effect, α2PI activities became elevated but the elevation disappeared after normalization. Elevated fibrinogen and FXIII levels in ESRD patients might contribute to the increased thrombosis risk, while decreased α2PI activity might be associated with elevated fibrinolytic potential.  相似文献   
66.
The inelastic mean free path (IMFP) is a fundamental material parameter. Presently the IMFPs calculated by the TPP-2M predictive formula (NIST SRD 71) are generally used. Elastic peak electron spectroscopy (EPES) is proved to be adequate for experimental determination of the IMFP denoted by λe. λe is smaller then λi (TPP-2M) values, due to surface losses, characterized by the SEP (surface excitation) Pse material parameter. The present research is focused on the experimental determination of Pse based on Tanuma's work. The Tanuma factor fsT is the ratio of experimental Ie and calculated Ic elastic peak intensities Ie(E)/Ic(E). The detection angle dependent Ic is proportional to ΔΩ, the solid angle of detection. The angular Ic(EΩ,αd) was calculated applying the EPESWIN software of Jablonski. In our work, experimental data of Goto were analysed for Si and Ni. Recent angularly resolved AREPES results of Jablonski and Zemek were quantified by fitting them at the 42° CMA (cylindrical mirror analyser) angle to absolute data of Goto and applying fsT. The models and SEP material parameters published by Werner et al., Ding et al., Kwei et al., Jablonski-Zemek and Nagatomi-Goto (Ni) and our data obtained by modifying Chen's data (Si) have been tested. The best approach was obtained using data of Werner for Si, and data of Nagatomi for Ni. The SEP corrected IMFPs λeco were deduced. The EPES SEP parameters were valid for AREPES by averaging over αd = 35-70°. EPES spectra are quantified by applying the backscattering yield.  相似文献   
67.
As the submerged shoot parts of common reed (Phragmites australis) can provide large surfaces for biofilm‐forming bacteria, extensive reed stands can effectively contribute to the self‐purification in the littoral zones of freshwaters. However, bacterial biofilm developed on reed surfaces have been studied only in still waters. In the present study, comparative examinations were performed on the planktonic and reed biofilm bacterial communities from two different riverine water bodies. Water and reed biofilm samples were taken at the beginning and end of the vegetation period from (a) a regulated side arm and (b) a separated oxbow of River Danube. Besides measuring physical and chemical environmental variables, planktonic bacterial cell numbers were detected by 4′,6‐diamidino‐2‐phenylindole staining method, and the bacterial communities were compared by denaturing gradient gel electrophoresis. Our results demonstrated that the structure and composition of bacterial communities correlated with different environmental variables and were different regarding both the habitats (planktonic vs. reed biofilm) and the types of riverine water bodies. The seasonal differences in the bacterial community structures were smaller in the river side arm than in the separated oxbow. In the water column, representatives of widespread and typical freshwater planktonic bacteria (“Candidatus Planktophila,” Limnohabitans, and Polynucleobacter), whereas, in the reed biofilm samples, phototrophic and plant associated bacteria were identified.  相似文献   
68.
Collaborative development environments allow a group of users to view and edit a shared item from geographically dispersed sites. Consistency maintenance in the face of concurrent accesses to shared entities is one of the core issues in the design of these systems. The paper introduces a lock based solution and three different algorithms that enable controlled, concurrent access to workflows for multiple application developers. Collaborative development of workflow applications promises better outcome in shorter time. The described method ensures that collaborators cannot break the consistency criteria of workflows by adding cycles or invalid edges to the graphs. A formal analysis of the three graph locking algorithms is also provided, focusing on the number of users who are allowed to edit a single workflow simultaneously. Based on the findings, a more powerful fourth graph locking algorithm is defined.  相似文献   
69.
Gergely     rp  d  J  nos  J  zsef 《Performance Evaluation》2003,53(3-4):209-223
This paper introduces new admission criteria that enable the use of algorithms based on the many sources asymptotics in real-life applications. This is achieved by a significant reduction in the computational requirements and by moving the computationally intensive tasks away from the timing-sensitive decision instant. It is shown that the traditional overflow probability type admission control method can be reformulated into a bandwidth requirement type and into a buffer requirement type method and that these methods are equivalent when used for admission control. The original and the two proposed methods are compared through the example of fractional Brownian motion (fBm) traffic.  相似文献   
70.
Many studies have demonstrated that infants can attribute goals to observed actions, whether they are presented live by familiar agents or on a computer screen by abstract figures. However, because most, if not all, of these studies rely on the repeated action presentations typical of infant studies, it is not clear whether infants are simply recognizing the completed action as goal directed, or whether they can productively infer a not-yet-achieved outcome from an ongoing action. We investigated this question by presenting 13-month-old infants with a single animated chasing event. Infants looked longer at the outcome of this action when, given the opportunity, the chaser did not catch the chasee than when it did. Crucially, this result was dependent on whether the action could be construed as efficient with regard to this goal state. This finding suggests the ability to infer the goal of an ongoing novel action and illustrates the productivity of 1-year-olds’ action understanding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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