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21.
Patty PJ  Frisken BJ 《Applied optics》2006,45(10):2209-2216
We compare results for the number-weighted mean radius and polydispersity obtained either by directly fitting number distributions to dynamic light-scattering data or by converting results obtained by fitting intensity-weighted distributions. We find that results from fits using number distributions are angle independent and that converting intensity-weighted distributions is not always reliable, especially when the polydispersity of the sample is large. We compare the results of fitting symmetric and asymmetric distributions, as represented by Gaussian and Schulz distributions, respectively, to data for extruded vesicles and find that the Schulz distribution provides a better estimate of the size distribution for these samples.  相似文献   
22.
对很多企业而言,灾难恢复只准成功,不许失败.当企业财务受挫,甚至生存受到挑战时,lT专家们必须确保企业的灾难恢复计划切实可行.当执行灾难恢复计划时,为保证有效的业务连续性,企业的每一个部门、每一个人都需协同工作,否则,灾难恢复有可能导致另一场灾难,而不是有效的业务保障措施.  相似文献   
23.
In a 22-year study, data were collected on aggressiveness and intellectual functioning in more than 600 subjects, their parents, and their children. Both aggression and intellectual functioning are reasonably stable in a subject's lifetime and perpetuate themselves across generations and within marriage pairs. Aggression in childhood was shown to interfere with the development of intellectual functioning and to be predictive of poorer intellectual achievement as an adult. Early IQ was related to early subject aggression but did not predict changes in aggression after age 8. Differences between early IQ and intellectual achievement in middle adulthood were predictable from early aggressive behavior. A dual-process model was offered to explain the relation between intellectual functioning and aggressive behavior. We hypothesized that low intelligence makes the learning of aggressive responses more likely at an early age, and this aggressive behavior makes continued intellectual development more difficult. (42 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
24.
Through our focused effort to discover new and effective agents against toxoplasmosis, a structure‐based drug design approach was used to develop a series of potent inhibitors of the enoyl‐acyl carrier protein (ACP) reductase (ENR) enzyme in Toxoplasma gondii (TgENR). Modifications to positions 5 and 4′ of the well‐known ENR inhibitor triclosan afforded a series of 29 new analogues. Among the resulting compounds, many showed high potency and improved physicochemical properties in comparison with the lead. The most potent compounds 16 a and 16 c have IC50 values of 250 nM against Toxoplasma gondii tachyzoites without apparent toxicity to the host cells. Their IC50 values against recombinant TgENR were found to be 43 and 26 nM , respectively. Additionally, 11 other analogues in this series had IC50 values ranging from 17 to 130 nM in the enzyme‐based assay. With respect to their excellent in vitro activity as well as improved drug‐like properties, the lead compounds 16 a and 16 c are deemed to be excellent starting points for the development of new medicines to effectively treat Toxoplasma gondii infections.  相似文献   
25.
“Color Theory for Automotive Coatings” is a state‐of‐the‐art learning approach to the world of automotive color. This learning tool provides important information to design engineers, color formulators, chemists, paint shop managers, color technicians, and anyone who wants to be more discerning about the science and communication of color. The content synthesizes both historic and current relevant color knowledge bases. The interactive educational design incorporates concepts of adult learning. The fundamentals of color and its application to the automotive industry are presented at the student's own pace. The learner has control of the learning process. © 2003 Wiley Periodicals, Inc. Col Res Appl, 28, 327–334, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10176  相似文献   
26.
In order to determine the actual threshold level of habitual physical activity necessary to obtain protective effects against degenerative diseases, valid, reliable, nonreactive, and precise instruments are needed. Because regular, low‐intensity exercise provides prophylactic effects, the ability to distinguish activity patterns should be a primary consideration when choosing an instrument to assess activity in the field. Although self‐report methods in the form of questionnaires are the instruments of choice when large populations are to be assessed, they are somewhat limited in their objectivity. The doubly labeled water (DLW) technique is a highly accurate and objective technique for assessing total daily energy expenditure that should be utilized more as a criterion measure for validating questionnaires that assess energy expenditure. However, the DLW technique remains too costly to be considered practical for large‐scale studies. Supplementing questionnaires with a personal interview does elicit more detailed data, but activity monitors provide a more objective measure of activity that can be used as an adjunct to questionnaires. Several models of activity monitors are capable of collecting and storing data for many days, weeks, or even months. More importantly, the internal real‐time clocks of these monitors allow the discrimination of activity patterns. Future studies should combine the use of these monitors with a suitable questionnaire.  相似文献   
27.
Objective: Discuss initial evaluation of a program for training faith community nurses (FCNs) to conduct cognitive–behavioral and spiritual counseling (CBSC) for rural dementia caregivers (CGs), and present 2 case studies on the use of CBSC for treating depression in this population. Study Design: Pre–post evaluation of the effectiveness of CBSC training and a case study analysis of the effectiveness of CBSC on CG problem improvement and depression. Outcome Measures: For FCN training, we used the FCN Counseling Comfort Scale, FCN Counseling Efficacy Scale, and the FCN Counseling Workshop Satisfaction Survey. The Problem Severity Scale and Center for Epidemiologic Studies Depression Scale were used in the case studies. Results: Significant post-training increases in FCN counseling comfort and perceived counseling efficacy were obtained. Case study findings provided evidence of substantial improvement in caregiving problems and reductions in depression. Conclusions: Preliminary outcomes of FCN training and CBSC for dementia CGs were promising. However, replication across the sample is required to evaluate the overall effectiveness of CBSC for reducing CG depression. Specific competencies and ethical considerations in supervising this form of intervention are also addressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
28.
Sooty Terns from the population that nests at Dry Tortugas, Florida, were found to have substantial burdens of cadmium, mercury and selenium. Analysis of selected tissues, faeces and eggs by neuteon activation techniques showed highest levels of mercury in eggs, feathers and blood; of cadmium in kidney and bone; and of selenium in kidney, liver and feathers.The concentrations of cadmium, mercury and selenium found in the eggs suggests that the heavy metals are being transmitted to succeeding generations. The significance of the concentrations, their effect on the reproductive success of the population, and the question of whether or not the metals transmitted to eggs represent “bio-magnification” merit further work.  相似文献   
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