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31.
Pankaj G Vashi Kristen Trukova Carolyn A Lammersfeld Donald P Braun Digant Gupta 《Nutrition journal》2010,9(1):60
Background
Serum 25-hydroxyvitamin D [25(OH)D] is the major circulating form of vitamin D and a standard indicator of vitamin D status. Emerging evidence in the literature suggests a high prevalence of suboptimal vitamin D (as defined by serum 25(OH)D levels of <32 ng/ml) as well as an association between lower serum levels and higher mortality in cancer. We investigated the effect of oral vitamin D supplementation as a means for restoring suboptimal levels to optimal levels in cancer. 相似文献32.
Thomas J. Stewart Ora E. Johannsson Kristen Holeck W. Gary Sprules Robert O'Gorman 《Journal of Great Lakes research》2010
We assessed changes in Lake Ontario zooplankton biomass, production, and community composition before (1987–1991) and after (2001–2005) invasion-induced ecosystem changes. The ecosystem changes were associated with establishment of invasive dreissenid mussels and invasive predatory cladocerans (Bythotrephes and Cercopagis). Whole-lake total epilimnetic plus metalimnetic zooplankton production declined by approximately half from 42.45 (g dry wt?m−2? year−1) during 1987–1991 to 21.91 (g dry wt?m−2? year−1) in 2003 and averaged 21.01 (g dry wt?m−2? year−1) during 2001–2005. Analysis of two independent data sets indicates that the mean biomass and biomass proportion of cyclopoid copepods declined while the same measures increased for the invasive predatory cladocerans. Changes in means and proportions of all other zooplankton groups were not consistent between the data sets. Cyclopoid copepod biomass and production declined by factors ranging from 3.6 to 5.7. Invasive predatory cladoceran biomass averaged from 5.0% to 8.0% of the total zooplankton biomass. The zooplankton community was otherwise resilient to the invasion-induced disruption as zooplankton species richness and diversity were unaffected. Zooplankton production was likely reduced by declines in primary productivity but may have declined further due to increased predation by alewives and invasive predatory cladocerans. Shifts in zooplankton community structure were consistent with increased predation pressure on cyclopoid copepods by alewives and invasive predatory cladocerans. Predicted declines in the proportion of small cladocerans were not evident. This study represents the first direct comparison of changes in Lake Ontario zooplankton production before and after the invasion-induced disruption and will be important to food web-scale investigations of invasion effects. 相似文献
33.
Dowdy Erin; Twyford Jennifer M.; Chin Jenna K.; DiStefano Christine A.; Kamphaus Randy W.; Mays Kristen L. 《Canadian Metallurgical Quarterly》2011,23(2):387
Reports an error in "Factor structure of the BASC–2 Behavioral and Emotional Screening System Student Form" by E. Dowdy, et al. (Psychological Assessment. np). There was an omission in the author note. The author note should have included a disclosure as follows, “Randy W. Kamphaus wishes to disclose a potential conflict of interest in that he receives a portion of royalties on net sales of BESS.” (The following abstract of the original article appeared in record 2011-04578-001.) The BASC–2 Behavioral and Emotional Screening System (BESS) Student Form (Kamphaus & Reynolds, 2007) is a recently developed youth self-report rating scale designed to identify students at risk for behavioral and emotional problems. The BESS Student Form was derived from the Behavior Assessment System for Children—Second Edition Self-Report of Personality (BASC–2 SRP; Reynolds & Kamphaus, 2004) using principal component analytic procedures and theoretical considerations. Using 3 samples, the authors conducted exploratory factor analyses (EFA) and confirmatory factor analyses (CFA) to understand the underlying factor structure of the BESS Student Form. The results of the EFA suggested that the SRP contained a 4-factor (i.e., Personal Adjustment, Inattention/Hyperactivity, Internalizing, School Problems) emergent structure, which was supported by CFA in 2 additional samples. Practical and research implications are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
34.
Ackerman Brian P.; Schoff Kristen; Levinson Karen; Youngstrom Eric; Izard Carroll E. 《Canadian Metallurgical Quarterly》1999,35(6):1355
This study examined the relations between alternative explanations of poverty cofactors and promotion processes and teacher reports of the problem behaviors of 6- and 7-yr old children from economically disadvantaged families (N?=?159). The results showed that single index representations of risk and promotion variables predicted child aggressive behaviors but not child anxious/depressed behaviors. An addictive model of individual risk indicators performed similarly. Similar indexes representing clusters of parent adjustment variables and family instability variables, however, differentially predicted aggressive and anxious/depressed behaviors, respectively. The results suggest the importance of promotion processes and representing environmental adversity at varying levels of specificity for children from economically disadvantaged families. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Kling Kristen C.; Hyde Janet Shibley; Showers Carolin J.; Buswell Brenda N. 《Canadian Metallurgical Quarterly》1999,125(4):470
Two analyses were conducted to examine gender differences in global self-esteem. In Analysis I, a computerized literature search yielded 216 effect sizes, representing the testing of 97,121 respondents. The overall effect size was 0.21, a small difference favoring males. A significant quadratic effect of age indicated that the largest effect emerged in late adolescence (d?=?0.33). In Analysis II, gender differences were examined using 3 large, nationally representative data sets from the National Center for Education Statistics (NCES). All of the NCES effect sizes, which collectively summarize the responses of approximately 48,000 young Americans, indicated higher male self-esteem (ds ranged from 0.04 to 0.24). Taken together, the 2 analyses provide evidence that males score higher on standard measures of global self-esteem than females, but the difference is small. Potential reasons for the small yet consistent effect size are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
Kristen Adlhoch 《History of Photography》2013,37(4):445-447
This article focuses on the photographs of public sculptures used on belle époque picture postcards of Brussels. The subject is approached from two perspectives. Firstly, we analyse the conventions of in situ photography of public sculpture in light of the genre’s reliance on painterly and photographic traditions, as well as its adoption of visual strategies derived from amateur and snapshot photography. Secondly, we explore the role of the photographic mise-en-scène of picture postcards in constructing an ideological as well as visual perspective on public monuments and the cityscape. The in situ photography of urban statues for picture postcards can be regarded as a photographic genre at the intersection of documentary art reproduction practices and amateur photography of the city. Moreover, the picture postcards discussed in this essay confirm and propagate dominant discourses on the monument and the cityscape, even if at the same time such visions were challenged. In the case of Brussels, the postcards demonstrate a preference for a monumental, impressive cityscape, worthy of representing the Belgian nation and capable of legitimising it through views of sculpture as a grand art, serving the worship of grands hommes. 相似文献
37.
38.
Stein Catherine H.; Abraham Kristen M.; Bonar Erin E.; Leith Jaclyn E.; Kraus Shane W.; Hamill Alexis C.; Gumber Shinakee; Hoffmann Erica; Fogo Wendy R. 《Canadian Metallurgical Quarterly》2011,25(3):449
The present intergenerational study examined the perceived impact of the recent U.S. economic crisis on a sample of 68 young adult–parent dyads. The relative contribution of perceived economic pressure, reports of adult child–parent relationship quality, and concerns about the economic future in accounting for variation in self-reports of psychological distress for adult children and their middle-aged parents were examined. Parents' concerns about their children's economic future accounted for variation in their reports of anxiety and depressed mood above and beyond that of perceived economic pressures and their views of the parent–child relationship. In contrast, for young adults, reports of personal economic pressure were generally related to self-reported anxiety and depressed mood. Implications of findings for research and practice are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
39.
Blumberg Mark S.; Sokoloff Greta; Kent Kristen J. 《Canadian Metallurgical Quarterly》1999,113(6):1274
Two experiments explored the cardiovascular consequences of extreme cold exposure and their relationship with ultrasound production in infant rats. Experiment 1 addressed the thermoregulatory and cardiovascular concomitants of ultrasound production during cold exposure in rats pretreated with saline or the ganglionic blocker chlorisondamine (5 mg/kg). For both groups, emission of ultrasound was associated with hypothermia and bradycardia. Experiment 2 explored whether the hypothermia experienced by pups in Experiment 1 is associated with increased blood viscosity, which is an important factor affecting venous return to the heart. Blood viscosity increased significantly as temperature decreased from 38°C to 22°C. These experiments suggest that, during extreme cold exposure, decreased cardiac output and increased blood viscosity combine to diminish venous return. The authors have hypothesized that pups respond to decreased return by recruiting the abdominal compression reaction, a physiological maneuver that propels blood back to the heart, resulting in emission of ultrasound as an acoustic by-product. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
Darin P. O'Brien Kristen A. Campbell Nathaniel W. Morken Robert J. Bair Ellen M. Heath 《Journal of The Association for Laboratory Automation》2001,6(2):67
Advancements in the fields of genomic screening, molecular pathology and clinical research have resulted in a major increase in the demand for high quality DNA and RNA. This escalating demand has resulted in a sample preparation bottleneck and an emphasis on the development of new technologies to automate the purification process. Gentra has developed the AUTOPURE LS™ nucleic acid purification instrument, a platform capable of high-throughput sample purification from large samples, such as 10 mL whole blood. This article presents data showing the equivalency of DNA purified using manual and automated processing. 相似文献