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1.
Data from 296 sibling pairs (mean ages 10 and 13 years), their primary caregivers, and census records were used to test the hypothesis that African American children's likelihood of developing conduct problems associated with harsh parenting, a lack of nurturant-involved parenting, and exposure to an older sibling's deviance-prone attitudes and behavior would be amplified among families residing in disadvantaged neighborhoods. A latent construct representing harsh-inconsistent parenting and low levels of nurturant-involved parenting was positively associated with younger siblings' conduct disorder symptoms, as were older siblings' problematic attitudes and behavior. These associations were strongest among families residing in the most disadvantaged neighborhoods. Future research and prevention programs should focus on the specific neighborhood processes associated with increased vulnerability for behavior problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This paper proposes a high capacity audio watermarking algorithm in the logarithm domain based on the absolute threshold of hearing of the human auditory system (HAS), which makes this scheme a novel technique. When considering the fact that the human ear requires more precise samples at low amplitudes (soft sounds), the use of the logarithm helps us design a logarithmic quantization algorithm. The key idea is to divide the selected frequency band into short frames and quantize the samples based on the HAS. Using frames and the HAS improves the robustness, since embedding a secret bit into a set of samples is more reliable than embedding it into a single sample. In addition, the quantization level is adjusted according to the HAS. Apart from remarkable capacity, transparency and robustness, this scheme provides three parameters (frequency band, scale factor and frame size) which facilitate the regulation of the watermarking properties. The experimental results show that the method has a high capacity (800–7,000 bits per second), without significant perceptual distortion (ODG >1) and provides robustness against common audio signal processing such as added noise, filtering and MPEG compression (MP3).  相似文献   
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The purpose of this work was to study whether exercise training induces changes in the lipid profile of rat aorta and nervous system and in the in vitro intrinsic responsiveness of these tissues to endothelin-1 (ET-1) treatment. The exercise program performed successfully produced the characteristic metabolic alterations of the trained state. Exercise training induced a large and significant increase in the levels of both aortic ethanolamine plasmalogens (PlasEtn) and glucosylceramides. In contrast, a decrease of aortic ceramide and cholesterol levels was evoked by exercise training. ET-1 increased PlasEtn content only in sedentary animals. An exercise-induced increase in cerebellum levels of ceramides and ceramide monohexosides was found. The cerebellum ceramide content was increased by FT-1 more noticeably in sedentary rats than in trained animals. In contrast, cerebral cortex was observed to be largely insensitive to both exercise training and ET-1 treatment. It was concluded that exercise training (i) induces changes in both vascular and cerebellar lipid profiles, the former being much more pronounced than the latter, and (ii) diminishes the aortic and cerebellar sensitivity to ET-1 action.  相似文献   
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The metal chelating activity, antioxidant properties, and the effect on cell growth of a polyphenol extract from Vicia sativa have been investigated, and compared to those of soybean. The extracts from V. sativa seeds contained three and five times more polyphenols and flavonoids than soybean, respectively. The soybean polyphenol extracts showed higher copper and iron chelating activity than those from V. sativa, although polyphenols from V. sativa were more effective in preventing β-carotene oxidation and showed higher reducing power and scavenging activity than soybean polyphenols. In addition, V. sativa polyphenols were toxic to THP-1 leukemic cells, as opposed to polyphenols extracted from soybean that did not show any antiproliferative activity at similar concentrations. In conclusion, V. sativa polyphenol extracts show promising antioxidant and antiproliferative activities that may be of interest from a functional point of view and for the revalorization of this ancient crop.  相似文献   
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In order to provide insights about cancer patients' online information seeking behaviors, the present study analyzes individuals' transaction log data and reports on how demographics, disease‐related factors, and psychosocial needs predict patterns of service use within a particular Interactive Cancer Communication System (ICCS). Study sample included 294 recently diagnosed breast cancer patients. Data included pretest survey scores of demographic, disease‐related, and psychosocial factors and automatically collected ICCS use data over the 4‐month intervention. Statistical analyses correlated pre‐test survey scores with subsequent, specific types of ICCS service usage. Patterns of online cancer information seeking differed according to the patients' characteristics, suggesting that lower income, less educated women and those lacking in information‐seeking competence use the computer and online services to the same or a greater degree if those services are made available to them. Results of this study can inform more effective resource development for future eHealth applications.  相似文献   
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This article's major objective is to effectively prepare the graduate student in psychology for the internship application process by providing critical and relevant information. Preparation begins early on in one's graduate career and usually involves the following steps: (a) establishing mentoring relationships, (b) preparing an application portfolio, (c) collecting information, (d) applying, (e) interviewing, (f ) ranking the selected agencies, and (g) responding on selection day. Information is also provided on how to use the Association of Psychology Postdoctoral Internship Centers (APPIC) Clearinghouse. Finally, a brief section is devoted to the process of choosing a non-APPIC site. Advance preparation can make this entire process easier and increase a student's chance of finding a suitable predoctoral internship in psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Two laboratory studies were conducted in which a new type of intervention was used to reduce ultraviolet radiation (UV) exposure from tanning booth use among college students (Time 1 Ns=70 and 134). The intervention uses UV photography to highlight the damage to facial skin caused by previous UV exposure. When the authors controlled for baseline measures of booth use, students in both studies who viewed their UV photographs reported less booth use at a follow-up session 3-4 weeks later than did students not shown a copy of their photograph. Also, in both studies, the decline in use was significantly mediated by a Tanning Cognition Index composed of variables suggested by the prototype-willingness (prototype) model of health risk: tanning attitudes, tanner prototypes, and willingness to engage in risky UV exposure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
The affiliation preferences of 151 adult heavy smokers who joined smoking cessation groups were assessed at the 1st group session and were then used to predict their smoking status 6 and 12 months later. Those who preferred to be in groups with other smokers who were having relatively little trouble quitting were more likely to be successful than were those who preferred others who were having more difficulty quitting. This prospective effect was mediated by psychological distancing from the image of the typical smoker: Preference for others who were doing well was associated with a decrease in perceived similarity to the typical smoker, which, in turn, was associated with successful cessation. Implications of these findings for cessation groups and social comparison theory are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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