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21.
Cross‐linked zein has been produced using glyoxal (GLY) as the cross‐linking reagent via reactive extrusion for the first time in a twin screw extruder using dilute sodium hydroxide as catalyst. Tri(ethylene glycol) was used as a plasticizer for various items. The extrudate was then ground and processed using either compression or injection molding. At the highest level of GLY (6%), tri(ethylene glycol) was used at 10% as a plasticizer to allow further processing to take place. With this formulation, samples could be obtained from the injection mold, however, the samples did not hold their molded shape due to the elasticity of the sample at the mold temperature. When lower levels of GLY were used, injection molded sample bars of similar quality to control were obtained. The physical properties of these samples were similar to control. At GLY levels of 1.75% and higher, the samples were resistant to dissolution by acetic acid. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
22.
This study evaluated the prevalence and associated risks of binge drinking, defined as having ≥4 drinks on an occasion in the past year, in a female patient population. Of 1,259 female Veterans Affairs patients surveyed, 780 reported drinking alcohol in the past year, and 305 (24% of respondents, 39% of drinkers) reported binge drinking in the past year; 84 (11% of drinkers) had done so monthly or more often. Age-adjusted logistic regression analyses indicated that women who reported past-year binge drinking monthly or more often reported significantly increased odds of morning drinking (odds ratio [OR]?=?40.3), others worrying about their drinking (OR?=?38.6), arguments after drinking (OR?=?13.5), hepatitis or cirrhosis (OR?=?3. 1), frequent injuries (OR?=?2.6), smoking (OR?=?3.7), drug use (OR?=?22.2), and multiple sexual partners (OR?=?4.6). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
24.
Using a longitudinal, systematic random sample of 490 postings, this study analyzed the type of social support provided, the strategies used to solicit social support, and the themes on the top 5 Yahoo! eating disorder discussion boards. Optimal match theory was used as the theoretical framework for the study. Results suggest that messages providing informational support were more prevalent than those providing instrumental support. Also, the findings revealed that the most frequent strategy for soliciting support was sharing experiences and the most frequent theme was positive affect. The results of the study highlight the significance of prosocial communication exchanges on these discussion boards.  相似文献   
25.
This study examined the relations among family structure, caregiver relationship history, aspects of environmental adversity, and teacher reports about the externalizing behaviors of 6- and 7-year-old children from economically disadvantaged families. Family structure contrasted intact families, stepfamilies, single-parent families, and cohabiting families. Problem behaviors were more frequent for children from unmarried families than from married families and were more frequent for boys than for girls from cohabiting families. Relationship history reduced the effects for family structure. Children's adjustment varied with both the current status and past stability of caregiver intimate relationships for disadvantaged families. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
26.
The purpose of this research was to evaluate the relative contributions of personal, affective, and social exchange characteristics to satisfaction with the best friendship. Senior adults (N?=?76) described and evaluated their best friendships in terms of positive and negative affect, equity, reciprocity of social support, and satisfaction. The individual's endorsement of communal and exchange orientations were included as personal characteristics. The study confirms that a communal orientation enhances satisfaction with a best friendship and that conflict and negativity detract from it. Social exchange characteristics were not related to friendship satisfaction. The need to reevaluate the role of social exchange in close relationships is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
27.

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   
28.
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   
29.
Collagen gel cell cultures were used to test the hypothesis that cells from peripheral parenchymal zones of the developing bovine mammary gland have greater proliferative and morphogenic potential than cells from the medial parenchymal mass. Tritiated thymidine was incorporated to assess cell proliferation. Dose responses for insulin-like growth factor one (IGF-I, 0 to 50 ng/ml) and transforming growth factor beta one (0 to 5 ng/ml) were determined for each cell population. Cells from the peripheral regions were two to three times more sensitive to the mitogenic action of IGF-I or serum. Transforming growth factor beta one concentrations of 12.5 to 500 pg/ml stimulated cell proliferation, but concentrations above 1 ng/ml were inhibitory. Peripheral cells showed a distinct biphasic response to addition of transforming growth factor beta one. Morphology of organoids was evaluated daily during culture and by histologic examination at the end of culture. Peripheral zone cells formed multi-layered cell structures that resembled native mammary parenchyma with serum or mammary gland extract. Our results indicate that epithelial cells of the peripheral and medial parenchymal zones in the ruminant mammary gland can differ in their proliferative and morphogenetic response to growth factor treatment in vitro. These differences likely reflect local tissue regulation necessary for sequential ductular and lobulo-alveolar development in vivo.  相似文献   
30.
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   
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