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991.
Reviews the book, School violence: Fears versus facts by Dewey G. Cornell (see record 2006-07405-000). This book provides a unique focus on common misperceptions regarding school violence. One of the most notable misperceptions is that school violence is on the rise. This is just one of the misperceptions that Cornell's book addresses. Each chapter of the book begins with a case example and fundamental question about school violence, followed by the presentation of research to answer the question. The book concludes with recommendations for what our schools need to prevent violence. These recommendations follow directly from the content of the book and include specific suggestions about eliminating ineffective programs in favor of empirically based efforts, amending legislation that has led to the adoption of ineffective zero tolerance policies, avoiding sensational news coverage of school violence, and making universal prevention a public health mission. The reviewer notes the importance of making data-based decisions about how to prevent and respond to school violence. In order to do this, it is critical to have knowledge of the facts, and to also be aware of common misperceptions about school violence. This book provides educators, graduate students, and parents with that information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
The performance of H2/O2 proton exchange membrane fuel cells (PEMFCs) fed with CO-contaminated hydrogen was investigated for anodes with PdPt/C and PdPtRu/C electrocatalysts. The physicochemical properties of the catalysts were characterized by energy dispersive X-ray (EDX) analyses, X-ray diffraction (XRD) and “in situ” X-ray absorption near edge structure (XANES). Experiments were conducted in electrochemical half and single cells by cyclic voltammetry (CV) and I-V polarization measurements, while DEMS was employed to verify the formation of CO2 at the PEMFC anode outlet. A quite high performance was achieved for the PEMFC fed with H2 + 100 ppm CO with the PdPt/C and PdPtRu/C anodes containing 0.4 mg metal cm−2, with the cell presenting potential losses below 200 mV at 1 A cm−2, with respect to the system fed with pure H2. For the PdPt/C catalysts no CO2 formation was seen at the PEMFC anode outlet, indicating that the CO tolerance is improved due to the existence of more free surface sites for H2 electrooxidation, probably due to a lower Pd-CO interaction compared to pure Pd or Pt. For PdPtRu/C the CO tolerance may also have a contribution from the bifunctional mechanism, as shown by the presence of CO2 in the PEMFC anode outlet.  相似文献   
993.
The effects of freezing, acidification, refrigeration and extended storage without refrigeration on measured concentrations of forms of nitrogen and phosphorus were assessed in water samples taken from polluted and unpolluted streams in dry and wet weather. Emphasis was placed on likely changes associated with the use of automatic samplers in field conditions. The response of measured nutrient concentrations to different preservation methods and to extended storage without preservation varied widely between samples. For polluted streams where nutrient concentrations were high (ammoniacal nitrogen >0.1 mg l−1; oxidised nitrogen, total Kjeldahl nitrogen, total and filterable phosphorus >1 mg l−1), there was generally little proportional change in nutrients other than ammoniacal nitrogen after up to 6 d of storage without preservation. Where nutrient concentrations were low, up to 90% of ammoniacal nitrogen, 50% of oxidised nitrogen, 84% of total Kjeldahl nitrogen and 67% of total phosphorus was lost after 6 d. If samples cannot be retrieved immediately, automatic samplers should be refrigerated where possible. Acidification is a suitable alternative for preservation of nitrogen. Samples for filterable phosphorus should be filtered as soon as possible after collection. In some circumstances, unpreserved samples may provide an acceptable level of accuracy for evaluation of broad temporal trends or estimation of nutrient loadings.  相似文献   
994.
995.
The volatile compounds responsible for the flavour of Australian‐grown ginger have been extracted using supercritical carbon dioxide. Both fresh and dried ginger samples have been examined and the major effects of the drying process are a reduction in gingerol content, an increase in terpene hydrocarbons and the conversion of some monoterpene alcohols to their corresponding acetates. © 2000 Society of Chemical Industry  相似文献   
996.
Surveys of 1217 undergraduate students supported the reliability (inter-item and test–retest) and validity of the Prosocial and Aggressive Driving Inventory (PADI). Principal component analyses on the PADI items yielded two scales: Prosocial Driving (17 items) and Aggressive Driving (12 items). Prosocial Driving was associated with fewer reported traffic accidents and violations, with participants who were older and female, and with lower Boredom Susceptibility and Hostility scores, and higher scores on Agreeableness, Conscientiousness, Openness, and Neuroticism. Aggressive Driving was associated with more frequent traffic violations, with female participants, and with higher scores on Competitiveness, Sensation Seeking, Hostility, and Extraversion, and lower scores on Conscientiousness, Agreeableness, and Openness. The theoretical and practical implications of the PADI's dual focus on safe and unsafe driving are discussed.  相似文献   
997.
The RAS gene family is among the most studied and best characterized of the known cancer-related genes. Of the three human ras isoforms, KRAS is the most frequently altered gene, with mutations occurring in 17%–25% of all cancers. In particular, approximately 30%–40% of colon cancers harbor a KRAS mutation. KRAS mutations in colon cancers have been associated with poorer survival and increased tumor aggressiveness. Additionally, KRAS mutations in colorectal cancer lead to resistance to select treatment strategies. In this review we examine the history of KRAS, its prognostic value in patients with colorectal cancer, and evidence supporting its predictive value in determining appropriate therapies for patients with colorectal cancer.  相似文献   
998.
Shellac-hydroxypropyl methylcellulose composite films (Sh-HPMC-CFs) were produced and the effects of emulsifier and shellac concentration on the Sh-HPMC-CFs were investigated. Two emulsifiers, stearic acid (SA) and lauric acid (LA), with three ratios of shellac to emulsifier (100:1, 20:1, and 10:1) were tested to select the best ratio of shellac to emulsifier before testing the effect of shellac concentration. When compared to pure HPMC film, the WVP was decreased by 6 and 11% in the Sh-HPMC-CFs containing shellac to LA (ShLA) ratios of 100:1 and 20:1, respectively. However, all the ShSA-HPMC-CFs had higher WVP than the pure HPMC film. In relation to mechanical properties, the ShLA(20:1)-HPMC-CF had the lowest reduction in TS when compared to a pure HPMC film. Therefore, ShLA(20:1) was selected for further characterization. Surface morphology, cross sectional image, thermal stability, WVP, and mechanical properties of the Sh-HPMC-CFs were also measured at varying shellac concentrations (0.1, 0.5, 1.0, and 1.5%). The 0.1 and 0.5% Sh-HPMC-CFs had good distribution of shellac in the film structure while the 1.0 and 1.5% Sh-HPMC-CFs exhibited some agglomeration of shellac. The 0.1 and 0.5% Sh-HPMC-CFs had better moisture barrier than the pure HPMC film. All Sh-HPMC-CFs had better thermal stability than the pure HPMC film and its thermal stability increased as shellac concentration increased.  相似文献   
999.
The ability to manipulate and customize the genetic code of living organisms has brought forth the production of genetically modified organisms (GMOs) and consumption of genetically modified (GM) foods. The potential for GM foods to improve the efficiency of food production, increase customer satisfaction, and provide potential health benefits has contributed to the rapid incorporation of GM foods into the American diet. However, GM foods and GMOs are also a topic of ethical debate. The use of GM foods and GM technology is surrounded by ethical concerns and situational judgment, and should ideally adhere to the ethical standards placed upon food and nutrition professionals, such as: beneficence, nonmaleficence, justice and autonomy. The future of GM foods involves many aspects and trends, including enhanced nutritional value in foods, strict labeling laws, and potential beneficial economic conditions in developing nations. This paper briefly reviews the origin and background of GM foods, while delving thoroughly into 3 areas: (1) GMO labeling, (2) ethical concerns, and (3) health and industry applications. This paper also examines the relationship between the various applications of GM foods and their corresponding ethical issues. Ethical concerns were evaluated in the context of the code of ethics developed by the Academy of Nutrition and Dietetics (AND) that govern the work of food and nutrition professionals. Overall, there is a need to stay vigilant about the many ethical implications of producing and consuming GM foods and GMOs.  相似文献   
1000.
Based on a sample of young adults in Miami-Dade County, Florida, this paper examined the extent to which there were sex differences in 3 coping style types: problem focused, emotion focused, and avoidance focused (Endler & Parker, 1990). Further examined were the extent to which sex differences in coping styles could be explained by sex differences in chronic strain; the extent to which sex differences in depressed mood could be explained by sex differences in coping style; and whether the effects of different coping style types on depressed mood varied by sex. Results suggested somewhat complex relationships among sex, coping, chronic strain, and depression. No sex differences in the use of problem-focused coping were observed when statistical controls for socioeconomic status were applied; however, women more often used avoidance-focused techniques. Although female respondents more often used emotion-oriented strategies compared to male respondents, such use did not prove to be fundamentally harmful for women. In fact, the effects of using emotion-focused strategies, such as the expression of feelings, reduced depressed mood for women, but not for men. Implications for practice and policy are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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