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排序方式: 共有1122条查询结果,搜索用时 9 毫秒
91.
K. Nürnberg Britta Ender Hans-Jürgen Papstein Jochen Wegner Klaus Ender Gerd Nürnberg 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1999,209(6):332-335
The adipose tissue development in muscle and the fatty acid composition of intramuscular fat of 200 bulls from three different breeds during growth was investigated. There were significant differences in quantitative and qualitative fat deposition which were genetically caused. The muscle of Galloway and White-blue Belgian bulls contained a high n–3 fatty acid content which is positive for human nutrition. During growth an increased deposition of saturated fatty acids into the adipocytes of muscle was observed. 相似文献
92.
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94.
Gang Yong Park Saehun MunYooheon Park Siyeon RheeEric A. Decker Jochen WeissD. Julian McClements Yeonhwa Park 《Food chemistry》2007,104(2):761-767
The influence of interfacial composition on the in vivo digestibility of emulsified and encapsulated lipids was investigated. An electrostatic layer-by-layer deposition technique was used to prepare soybean oil-in-water emulsions that contained lipid droplets coated by lecithin or by lecithin–chitosan. Thirty six 4-week-old male mice were divided into four groups and fed treatment diets for 4 weeks; atherogenic diets supplemented with (A) non-emulsified fat, without chitosan (control), (B) non-emulsified fat, with chitosan, (C) emulsified fat, without chitosan, or (D) emulsified fat encapsulated by chitosan. There were no differences in body weights, food intake, major organ weights, or fecal fat contents between all treatment groups, where total fat absorption was >90%. The results suggest that encapsulation of lipids by chitosan does not inhibit their in vivo digestibility, even though previous studies indicate that chitosan does inhibit their in vitro digestibility. Consequently, it should be possible to use chitosan to microencapsulate lipids and lipid-soluble components without compromising their bioavailability, although further human studies are needed to confirm this. 相似文献
95.
Selection times of drop-down menus are in many ways influenced by cognitive and motor processes of the user and by design variables of the menu. Since the number of these variables is too large, the contribution of individual variables to selection time cannot be assessed by using factorial designs. Multiple regression is introduced to solve this problem. The technique uses selection times as criterions and a set of general menu characteristics as predictors. The non-standardized slopes β report the increase ( or decrease) in selection time which can be assessed for each predictor. In a first experiment, the validity of the technique was demonstrated replicating various well-known effects in a mouse-driven editor. For example, the selection times increased with the number of subordinate menu items or atypical items. Further, due to motor components of the mouse movement, selection times depended on the spatial position of an item within the menu. In a second experiment, mouse selection was replaced by key selection to stress cognitive processes contributing to response times. The technique yielded results that were sensitive to this variation. Limitations of the technique are discussed. 相似文献
96.
Processes of coping with performance deficits in different domains of functioning were investigated in a 4-year longitudinal study involving a core sample of 762 participants (initial age range: 58-81 years). Compensatory efforts to counteract functional impairments were found to increase up to the age of 70 years. Above that age, a decrease in compensatory efforts was observed that was linked to a decrease in the availability and efficiency of action resources. Contentment with actual performance levels remained stable across the entire age range of the study. Stability of self-evaluations was found to depend on adjustment of personal standards: Scarce action resources were accompanied by a lowering of personal comparison standards and by a downgrading of the importance of the respective domains. Accepting more lenient standards of comparison was found to buffer negative effects of performance deficits on contentment with performance among the older participants. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Christine Bratrich Bernhard Truffer Klaus Jorde Jochen Markard Werner Meier Armin Peter Matthias Schneider Bernhard Wehrli 《河流研究与利用》2004,20(7):865-882
Hydropower is the most important renewable electricity source worldwide. It shows clear advantages for the global CO2 balance but creates serious ecological impacts on a local scale. As a consequence, concern for the conservation of natural river ecosystems is growing within society and more people are willing to pay extra for so‐called ‘green electricity’. The definition of ‘green’, however, is not straightforward and customers cannot directly examine the quality of electricity products. Therefore, credible certification of high ecological standards is essential for successful green electricity marketing. In this paper we introduce a new assessment procedure for evaluating environmentally compatible hydropower production. This so‐called ‘Green Hydro’ concept was developed in the context of a multidisciplinary case study on a 400 MW hydropower scheme in the Southern Alps of Switzerland. The concept guarantees both general standards for different schemes operating in different types of watersheds and flexibility for local particularities. We developed an environmental management matrix that considers basic criteria and eco‐investments and covers five environmental areas of concern (i.e. hydrological character, connectivity, morphology, landscape, and biological communities). The ecological perspective is complemented by five management domains (i.e. instream flow regimes, hydropeaking, reservoir and bedload management, and power plant structures). Applying assessment and modelling tools for the Green Hydro procedure showed that dynamic habitat models allowed quantification of the effects of different instream flow regulations at morphologically distinct sites. In this case, morphological restoration could be more beneficial than increasing the minimum flow. The first experience with the Green Hydro certification is encouraging. So far, 13 facilities have successfully passed the certification procedure. They produce a total of 186 GWh green electricity per year, which is sufficient for the supply of almost 40 000 households in Switzerland. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
98.
Christian Gertz Hans‐Jochen Fiebig 《European Journal of Lipid Science and Technology》2006,108(12):1066-1069
The “Joint Committee for the Analysis of Fats, Oils, Fatty Products, Related Products and Raw Materials (GA Fett)” has developed the following method for the determination of isomeric diacylglycerols in virgin olive oils to detect the freshness of oils. It is intended to include this method in Section C, Chapter VI of the German Standard Methods.* 相似文献
99.
Jochen Wingbermuehle 《The Journal of VLSI Signal Processing》1998,20(1-2):81-96
This contribution describes the creation of highly realistic 3D models of participants for distributed 3D videoconferencing systems. These models consist of a flexible triangular mesh surrounding an interior skeleton structure, which is based on a simplified human skeleton. The vertices of the predefined mesh template are arranged in rigid rings along the bones of the skeleton. Using 3D data obtained by a stereoscopic approach the size and shape of this initial mesh is adapted to the real person. Adaptation allows to texture the model from real images leading to a natural impression. The mesh organization in rigid rings gives an efficient way for surface deformation according to the skeleton movements. The resulting model is transmitted once and subsequently animated using the simple parameter set of the interior skeleton structure. 相似文献
100.