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101.
102.
This note exhibits how the implementation of the Total Loads Standard for issuing tradable water rights along a river basin can cause a significant location-induced economic disadvantage to some of the agents located along a given river site. Analysis shows, however, that this issue can be resolved by a modification of the original Total Load Standard regarding the handling of so called critical zones in which the desired water quality level is otherwise not upheld.  相似文献   
103.
Physical strain is usually evaluated physiologically by using the heart rate (HR) or psychologically using scaled perceived exertion (PE). In order to explore the relationship between these approaches, we compared the series of both measurements taken simultaneously during work on a bicycle ergometer. A total of 29 participants aged between 27 and 41, 42 and 56, and 57 and 71 years took part in 28 minutes of cycling with systematically increased and decreased load as well as in 7 hours of continuous cycling with low to medium exertion, interrupted by brief peak loads at high to very high exertion levels. Results revealed that, while both measurements are suitable to capture physical strain, HR is not as specific as PE. The older participants further perceived comparable physical loads as more demanding as the younger participants. With an aging workforce, results have potential implications for the organisation of work places.  相似文献   
104.
Over the past several years, students, academic program faculty, and internship training directors have become increasingly concerned about the inequity between the demand for predoctoral internship slots and the limited supply of those placements. This article presents data from the 1999 Association of Psychology Postdoctoral and Internship Centers' (APPIC) Match, along with the results of 2 studies conducted by the authors. Results indicate that the number of internship positions available in the U.S. and Canada may be nearly balanced with the number of first-time internship applicants and that the current imbalance may result, in large part, from a carryover of unplaced applicants from previous selection processes. Furthermore, approximately ? of unmatched applicants are able to find internship positions subsequent to the conclusion of the matching process, although many of these positions are in non-American Psychological Association-accredited and non-APPIC-member programs. Implications of these findings for the profession and for student applicants are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
Nos observations au secondaire et au collégial et les travaux menés sur la transition secondaire postsecondaire en mathématiques ont permis de documenter un ensemble de ruptures dans le passage d'un ordre à l'autre, soulignant l'importance de s'attarder à l'articulation entre ces deux ordres. C'est afin de mieux comprendre ces articulations possibles qu'une recherche collaborative a été menée avec des enseignants des deux ordres. L'analyse, puisant ses fondements en ethnométhodologie, fait apparaître l'utilisation du symbolisme comme un thème central de cette articulation interordres, et permet de retracer une trajectoire d'harmonisation qui se développe durant les rencontres en lien avec cette utilisation.  相似文献   
106.
In this paper, we introduce a two‐layered approach addressing the problem of creating believable mesh‐based skin deformation. For each frame, the skin is first deformed with a classic linear blend skinning approach, which usually leads to unsightly artefacts such as the well‐known candy‐wrapper effect and volume loss. Then we enforce some geometric constraints which displace the positions of the vertices to mimic the behaviour of the skin and achieve effects like volume preservation and jiggling. We allow the artist to control the amount of jiggling and the area of the skin affected by it. The geometric constraints are solved using a position‐based dynamics (PBDs) schema. We employ a graph colouring algorithm for parallelizing the computation of the constraints. Being based on PBDs guarantees efficiency and real‐time performances while enduring robustness and unconditional stability. We demonstrate the visual quality and the performance of our approach with a variety of skeleton‐driven soft body characters.  相似文献   
107.
A 0.3% Au/Al2O3 catalyst prepared by the incipient wetness (IW) method was investigated in the continuous-flow liquid-phase glucose oxidation. Therefore, a continuous stirred tank reactor (CSTR) system equipped with an ultrasonic separator was used. The continuous-flow glucose oxidation was carried out at 40 °C, pH 9 and 1 bar oxygen partial pressure. Residence time and glucose concentration were varied. The IW gold catalyst showed very high activity and selectivity to gluconic acid within its 110 days of operation and, thus, an excellent long-term stability. Even after severe microbial contaminations of the catalyst, its activity could be completely restored by in situ regeneration with 2-propanol.  相似文献   
108.
In this work, two deposition–precipitation methods for the preparation of gold catalysts for glucose oxidation were investigated. Thus far, gold colloids immobilized on carbon have been used for catalytic glucose oxidation, but the long-term stability of these systems was not sufficient. To improve the long-term stability we used the deposition–precipitation methods using NaOH (DP NaOH) or urea (DP urea) as precipitation agents as they were described by Haruta and Dekkers, respectively, using alumina as a support material. With these methods, it was possible to prepare highly active and selective catalysts which showed an excellent long-term stability. DP urea was found to be the preferred method, because in contrast to DP NaOH, no losses of gold occurred during the preparation, and it was possible to adjust various gold contents up to 10 wt% Au.  相似文献   
109.
Native milk fat globules of various mean diameters, ranging from d43 = 2.3 µm to 8.0 µm, were obtained using microfiltration of raw whole milk. After milk fat globule washing, the milk fat globule membrane (MFGM) was separated by manual churning. After total lipid extraction and separation of polar lipids, their phospholipid (PL) and sterol composition was measured using thin‐layer chromatography, methyl ester analyses by gas chromatography, and gas chromatography coupled to mass spectrometry. The main PL species were phosphatidylethanolamine, phosphatidylcholine and sphingomyelin. The respective fatty acid composition of each PL species was measured. Many different minor bioactive sterols were detected in the MFGM, e.g. lanosterol, lathosterol, desmosterol, stigmasterol and β‐sitosterol. No significant differences in the PL and sterol profile were found between MFGM extracted from small and large milk fat globule fractions.  相似文献   
110.
Wang ZQ  Weber N  Lou YJ  Proksch P 《ChemMedChem》2006,1(4):482-488
In the search for estrogen receptor (ER) modulators, a series of prenylflavonoids were found to be widely distributed amongst tonic herbal medicines and to possess estrogen-like activity in MCF-7/BOS cells, as evaluated by an estrogen-screening assay. Cell-cycle analysis revealed that the stimulatory effects of these compounds toward cell proliferation were elicited at the G1-S checkpoint and could significantly increase the S-phase population of MCF-7 cells under hormone-free conditions. ER-responsive gene (PS2, PgR) and protein (PgR) expression was also detected; mRNA and protein-expression levels for PS2 and PgR were up-regulated by the compounds in a dose-dependent manner. These effects could be inhibited by the pure ER antagonist ICI 182,780 ((7alpha-[9-{4,4,5,5,5-pentafluoropentyl}sulfinyl]nonyl)estra-1,3,5(10)-triene-3,17beta-diol). It was therefore concluded that the estrogen-like effects of these prenylflavonoids were mediated primarily through ERs. Furthermore, to explore the structure-activity relationship based on the estrogen receptor and detailed molecular mechanisms among the prenylflavonoids, protein-ligand docking simulations were carried out by using the DS-MODELING software package. The binding affinity of each prenylflavonoid toward ERalpha was scored, and the receptor-ligand interaction was also analyzed to provide the simulation characteristics of virtual molecular recognition mechanisms.  相似文献   
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