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51.
Antonio Vega-Gálvez Kong Ah-HenMarcelo Chacana Judith VergaraJavier Martínez-Monzó Purificación García-SegoviaRoberto Lemus-Mondaca Karina Di Scala 《Food chemistry》2012,132(1):51-59
The aim of this work was to study the effect of temperature and air velocity on the drying kinetics and quality attributes of apple (var. Granny Smith) slices during drying. Experiments were conducted at 40, 60 and 80 °C, as well as at air velocities of 0.5, 1.0 and 1.5 m s−1. Effective moisture diffusivity increased with temperature and air velocity, reaching a value of 15.30 × 10−9 m2 s−1 at maximum temperature and air velocity under study. The rehydration ratio changed with varying both air velocity and temperature indicating tissue damage due to processing. The colour difference, ΔE, showed the best results at 80 °C. The DPPH-radical scavenging activity at 40 °C and 0.5 m s−1 showed the highest antioxidant activity, closest to that of the fresh sample. Although ΔE decreased with temperature, antioxidant activity barely varied and even increased at high air velocities, revealing an antioxidant capacity of the browning products. The total phenolics decreased with temperature, but at high air velocity retardation of thermal degradation was observed. Firmness was also determined and explained using glass transition concept and microstructure analysis. 相似文献
52.
A pronounced degree of vertical imbalance in Australian fiscal federalism has placed increasing financial pressures on lower levels of government, including local government. This has led local government to seek additional ways of financing infrastructure development through developer charges. Due to the lower priority the Australian Bureau of Statistics has accorded local government statistics in recent years, it has been difficult to gauge the extent of use of developer charges as a revenue source. This paper attempts to review the evolution of developer contributions policy and describe the increasing importance of these charges in Australian local government, with special emphasis on New South Wales. 相似文献
53.
Reinvestigation of the Lewis acid catalyzed rearrangement of some open-chain permethyloligosilanes with the Al(Fe)Cl(3) catalyst system exhibited several cases of additional reactivity: namely, a fragmentation/cyclization reaction. Introduction of (trimethylsilyl)methyl substituents into the oligosilane substrates strongly facilitated this reaction, yielding cyclic or bicyclic carbacyclosilanes. Investigations concerning the composition of the catalyst system indicated that the incorporation of about 0.1% FeCl(3) into the AlCl(3) lattice provided an effective catalyst. 相似文献
54.
Kamran Sayrafian-Pour Wen-Bin Yang John Hagedorn Judith Terrill Kamya Yekeh Yazdandoost Kiyoshi Hamaguchi 《International Journal of Wireless Information Networks》2010,17(3-4):105-112
Information regarding the propagation media is typically gathered by conducting physical experiments, measuring and processing the corresponding data to obtain channel characteristics. When this propagation media is human body, for example in case of medical implants, then this approach might not be practical. In this paper, an immersive visualization environment is presented, which is used as a scientific instrument that gives us the ability to observe RF propagation from medical implants inside a human body. This virtual environment allows for more natural interaction between experts with different backgrounds, such as engineering and medical sciences. Here, we show how this platform has been used to determine channel models for medical implant communication systems. 相似文献
55.
56.
Many people believe that the “mad genius” notion, which has been a favorite cultural fixture for centuries, is based on established scientific fact. Much of the evidence for the connection between great creativity and great pathology, particularly affective disorder, comes from the writings of psychiatrists Nancy Andreasen and Arnold K. Ludwig and psychologist Kay Redfield Jamison. For two decades, their studies and books have been widely referenced in both the popular and professional press without critique or comment and often without much detail, suggesting that few people have spent much time with the originals. This article examines their most influential works, encouraging readers to evaluate this evidence for themselves, because the author believes that many of their claims have had unfortunate implications for the perception of creativity and the credibility of psychological research in general. The author considers the inherent difficulties of generating any scientific findings in this area, and concludes by discussing the signs of a hopeful trend to celebrate, rather than pathologize, people with exceptional gifts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
After a brief history of the Committee on International Relations of the American Psychological Association, 3 points are made about international psychological research that matters. First, it matters when the definition of the research problem area and the findings can potentially be reflected in policy change, in the practice of educators or psychologists, or in the mindsets of a new generation of researchers. Person-centered analysis of adolescents’ social and political attitudes has this potential and can complement variable-centered analysis. A cluster analysis of the IEA Civic Education Study’s data in 5 Western European and 5 Eastern European countries illustrates this. The following 5 clusters of adolescents were identified: those supportive of social justice but not participative, those active in conventional politics and the community, those indifferent, those disaffected, and a problematic cluster of alienated adolescents. Second, research that matters is situated in a cultural context. It is proposed that publications using data from any single country be required to include information about the cultural context in which the research was conducted. Finally, it matters that attention be given to the dynamics of the collaborative international research process, not only to research results. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Objective: Individuals may desire to diet or restrain from eating certain foods while attempting to quit smoking out of concern for weight gain. However, previous research and clinical tobacco treatment guidelines suggest that concurrent dieting may undermine attempts to quit smoking. The current study applied the self-control strength model, which posits that self-regulation relies on a limited strength that is consumed with use, to test whether resisting tempting sweets would lead to a greater likelihood of subsequent smoking. Design: Participants were 101 cigarette smokers randomly assigned to resist eating either from a tempting plate of sweets or from a plate of less tempting vegetables. All participants were then given a 10-min recess. Main Outcome Measures: Whether participants smoked during the break, measured with a breath carbon monoxide sample, served as the primary dependent variable. Results: As predicted, participants who resisted sweets were more likely to smoke during the break (53.2%) than those who resisted vegetables (34.0%), χ2(1, N = 101) = 3.65 p 相似文献
59.
Sallis James F.; Prochaska Judith J.; Taylor Wendell C.; Hill James O.; Geraci John C. 《Canadian Metallurgical Quarterly》1999,18(4):410
Psychological, biological, social, and physical environmental variables were examined for their association with physical activity of young people. A national sample of 1,504 parents and children in Grades 4–12 were interviewed by telephone. Twenty-two potential determinants were assessed along with an 11-item child physical activity index (α?=?.76). Hierarchical multiple regressions were conducted separately for 6 age–sex subgroups. Percentage of variance explained ranged from 18% for boys in Grades 4–6 to 59% for girls in Grades 10–12. Three variables had strong and consistent associations with the child physical activity index that generalized across subgroups: use of afternoon time for sports and physical activity, enjoyment of physical education, and family support for physical activity. These 3 variables should be targeted for change to promote physical activity in all groups of young people. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Possemato Kyle; Wade Michael; Andersen Judith; Ouimette Paige 《Canadian Metallurgical Quarterly》2010,2(3):218
Growing evidence suggests that posttraumatic stress disorder (PTSD) is associated with poorer health status (e.g., more medical disease, physical symptoms, and sick visits to health care professionals) among veterans who served in Operation Enduring Freedom (OEF) in Afghanistan and Operation Iraqi Freedom (OIF) in Iraq. We investigated whether PTSD, depression, and substance use disorders independently predicted health status over time among OEF/OIF veterans. Information regarding psychiatric and medical conditions and health care utilization was culled for 4,463 OEF/OIF veterans enrolled in Veterans Administration primary care for a period of 6 years. Data were analyzed using multilevel modeling and generalized estimating equations. Results suggest that PTSD, depression, and substance use disorders are independently associated with increased medical disease burden and mental health care utilization but not increased medical health care utilization. The association between PTSD and medical disease burden strengthened over time. These data suggest that OEF/OIF veterans with PTSD may be at risk for increasingly poorer physical health in terms of medical disease burden over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献