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41.
Nadine Müller Sabine Ellinger Birgit Alteheld Gudrun Ulrich‐Merzenich Heiner K. Berthold Hans Vetter Peter Stehle 《Molecular nutrition & food research》2010,54(11):1636-1645
White tea (WT) is rich in flavan‐3‐ols as green tea (GT) and might provide health protective effects due to the strong antioxidant properties of flavan‐3‐ols. Since intervention studies with WT are lacking, we evaluated the effects of WT consumption on antioxidant status, antioxidant capacity and biomarkers of oxidative stress compared to water and GT. After an overnight fast, 70 healthy non‐smokers were randomized to consume 600 mL of WT, GT or water (control). Plasma (epi‐)catechin and epi(gallo)catechingallate, antioxidant capacity (Folin assay, trolox equivalent antioxidant capacity test), 8‐iso‐prostaglandin F2α, ascorbic acid and uric acid were determined before and several times within 8 h after consumption. DNA strand breaks were measured in vivo and ex vivo (H2O2 stimulation) in leukocytes. Plasma flavan‐3‐ols significantly increased after WT and GT ingestion. Trolox equivalent antioxidant capacity was lower after 5 h in controls versus WT (p=0.031) and GT (p=0.005). Folin‐Ciocalteu reducing capacity, ascorbic and uric acid as well as markers of oxidative stress (8‐iso‐prostaglandin‐F2α, DNA strand breaks) were not affected by the beverages. A short‐term increase of catechins does not change plasma antioxidant capacity in healthy subjects. Conclusions with respect to health protective effects of WT and GT on the basis of these biomarkers can, thus, not be drawn. 相似文献
42.
Anu Kärkkäinen Panu Pekko James Dekker Nadine Pesonen Mika Suhonen Aarne Oja Jukka Kyynäräinen Heikki Seppä 《Microsystem Technologies》2005,12(1-2):169-172
We have designed and manufactured a micromachined moving plate capacitor to be used as an AC voltage reference in electrical metrology. The reference is based on the characteristic AC current–voltage curve of the component having a maximum, the value of which ideally depends only on the geometry of the component and material properties of single crystalline silicon. The electrode surface stability is essential in this application and hence a new fabrication process has been developed to metallize both surfaces of an electrostatically actuated micromachined structure. The stability of the AC reference voltage at a frequency of 100 kHz and an RMS voltage value 6.4 V was measured to be ±60 ppm over 14 h. 相似文献
43.
Mickael Daubie Philippe Levecq & Nadine Meskens 《International Transactions in Operational Research》2002,9(5):681-694
Credit scoring is the term used to describe methods utilized for classifying applicants for credit into classes of risk. This paper evaluates two induction approaches, rough sets and decision trees, as techniques for classifying credit (business) applicants. Inductive learning methods, like rough sets and decision trees, have a better knowledge representational structure than neural networks or statistical procedures because they can be used to derive production rules. If decision trees have already been used for credit granting, the rough sets approach is rarely utilized in this domain. In this paper, we use production rules obtained on a sample of 1102 business loans in order to compare the classification abilities of the two techniques. We show that decision trees obtain better results with 87.5% of good classifications with a pruned tree, against 76.7% for rough sets. However, decision trees make more type–II errors than rough sets, but fewer type–I errors. 相似文献
44.
Reviews the book, Handbook of psychotherapy supervision by C. Edward Watkins Jr. (see record 1997-08923-000). This book offers a forum for some of the most influential thinkers of our time to discuss what is probably the most critical aspect of learning how to become a therapist: clinical supervision. The book is well organized, comprehensive, and informative. In it, the elusive nature of teaching how to conduct psychotherapy is explored and clarified from a variety of perspectives and across myriad contexts. Overall, the book provides a wealth of information in an organized and readable fashion. Nonetheless, the topics explored include some areas that were not covered adequately. For example, the book would have been further enhanced had the subject of supervisory failures been given more attention, as we know that learning from past errors often provides the most valuable teaching opportunities. Despite a few minor criticisms, the book serves as a wonderful reference for practitioners, students, and teachers of psychotherapy. While extremely useful for the beginning supervisor, the book is also a valuable resource for seasoned supervisors who wish to expand or challenge their ways of thinking about supervision. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Tharinger Deborah J.; Lambert Nadine M.; Bricklin Patricia M.; Feshbach Norma; Johnson Neal F.; Oakland Thomas D.; Paster Vera S.; Sanchez William 《Canadian Metallurgical Quarterly》1996,27(1):24
National, state, and local education reform agendas have been on a fast track for more than a decade. Although some psychologists have been active in promoting psychology and psychological services in education reform initiatives, knowledge about their efforts is fragmented. In order to educate psychologists about education reform, this article highlights the impetus for the recent education reform movement, briefly reviews the latest waves of education reform, and discusses the development of the National Education Goals. Then, an argument is made for the integration of education, health, and social reform initiatives; state-level education reform principles and initiatives are highlighted, illustrated by the systemic education reform mandate in Kentucky. Next, progress toward the development and implementation of an APA-sponsored response to the National Education Goals is discussed. Finally, objectives and roles for psychologists in advancing education reform are presented, and guidelines for the education and training of future psychologists are introduced. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
The rapid mixing of reagents is a crucial step for on-chip chemical and biological analysis. It has been recently suggested that microfluidic mixing can be greatly enhanced by simply using time pulsing of the incoming flow rates of the two fluids to be mixed (Glasgow, I.; Aubry, N. Lab Chip 2003, 3, 114-120). This paper elaborates on the latter technique, showing through computational fluid dynamics how the mixing efficiency strongly depends on certain dimensionless parameters of the system, while remaining nearly insensitive to others. In particular, it is demonstrated that higher Strouhal numbers (ratio of flow characteristic time scale to the pulsing time period) and pulse volume ratios (ratio of the volume of fluid pulsed to the volume of inlet/outlet intersection) lead to better mixing. This paper also presents a physical device capable of mixing two reagents using pulsing, which shows improved mixing with greater values of the Strouhal number. 相似文献
47.
Turrisi Rob; Mastroleo Nadine R.; Mallett Kimberly A.; Larimer Mary E.; Kilmer Jason R. 《Canadian Metallurgical Quarterly》2007,21(4):453
The present study used perspectives from the general literature on college alcohol consumption to examine mediational influences of peer, environmental, and parental variables on heavy drinking for student athlete and nonathlete samples. Eight hundred thirty-five freshmen who differed in organized sports involvement were compared on heavy drinking outcomes, peer norms, environmental influences, and parental communication. College athletes reported significantly more heavy drinking experiences than nonathletes. Peer norms, environmental influences, and parental communication were all significant mediators of the athlete-heavy drinking relationship. Athletes reported a higher perception of peer drinking, peer approval of drinking, higher alcohol availability, and direct drink offers, which, in turn, were related to higher rates of heavy drinking. Parental communication mediated the athlete-heavy drinking relationship differently, depending on the specific topic of conversation. Discussion surrounding the importance of incorporating a variety of interventions aimed at reducing collegiate athlete drinking on the basis of the peer, environmental, and parental influences observed in the present analyses are presented. Limitations and directions for future research are also noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
An efficient sequential optimization approach for complex computer models was presented by Jones et al. (1998). After fitting a stochastic process model based on an initial space filling design, this model is sequentially refined by the expected improvement criterion. This criterion balances the need to search in areas in the design space where the prediction is optimal with the need to search where the model uncertainty is high. This approach can easily be extended to physical processes. Since in practice the overall quality of products of production processes is assessed by more than one response, a multivariate version of the expected improvement criterion is proposed based on desirability functions. This criterion is then used to optimize a metal spinning process. 相似文献
49.
Nadine Wittmann 《Water Resources Management》2014,28(5):1309-1325
Water scarcity is becoming an increasingly relevant issue in many regions of the world as demand for water continues to grow. As a result, the need for finding measures that efficiently allocate increasingly scarce water resources has become a primary topic on the agendas of many water resource management authorities. This paper presents an innovative approach that provides further insight into the connection between hydrological, environmental, and economic aspects along a river basin. In short, it analyzes how land rents along a river basin are affected by managing water pollution along a river basin, given certain hydrological characteristics of the river basin. Results show that, without the implementation of a water management system to control water quality, the negative external effects of upstream water discharges on downstream locations can be internalized through a decrease in downstream land rents. However, the analysis presented in this paper also reveals that it is not only the absence or the presence of a water management system that has a significant impact on the real estate market along the river basin. Moreover, the market outcome also varies with the type of water resources management system implemented. 相似文献
50.
Carmen Castañeda Nadine Pourthie´ Jean-Claude Souyris 《International journal of remote sensing》2013,34(7):1861-1884
A high density of local natural and human-induced ground deformation structures resulting from the presence of evaporites occur extensively around Zaragoza (NE Spain), posing risks to infrastructure, buildings and agriculture. We studied the potential of a series of interferograms constructed from 29 European Radar Satellite (ERS)-1/2 images to detect different types of ground deformation related to evaporite dissolution, landslides and mining subsidence. We examined the factors involved in the usefulness and quality of interferograms, especially in relation to coherence and atmospheric circumstances. Favourable conditions were found in desert or developed areas, while agricultural practises caused decorrelation in most sinkhole-prone areas. Results are consistent with previous geomorphological data and indicate that different natural and human-induced deformation phenomena can be detected in a time lag less than 5 years in evaporite areas. Advanced interferometric techniques based on time series of SAR images are needed for precise measurement and monitoring purposes. 相似文献