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81.
Patients with schizophrenia display numerous cognitive deficits, including problems in working memory, time estimation, and absolute identification of stimuli. Research in these fields has traditionally been conducted independently. We examined these cognitive processes using tasks that are structurally similar and that yield rich error data. Relative to healthy control participants (n = 20), patients with schizophrenia (n = 20) were impaired on a duration identification task and a probed-recall memory task but not on a line-length identification task. These findings do not support the notion of a global impairment in absolute identification in schizophrenia. However, the authors suggest that some aspect of temporal information processing is indeed disturbed in schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
A controlled study evaluating the effectiveness of exposure plus response-prevention treatment of bulimia nervosa was conducted in a sample of 47 women. This was a four-group comparison involving three treatment conditions and a waiting-list control group. The three treatment conditions were (a) exposure plus response prevention conducted in a single setting (clinic), (b) exposure plus response prevention conducted in multiple settings (clinic, patients' homes, and restaurants), and (c) cognitive–behavioral therapy without exposure plus response prevention. All treatment was provided to groups of 3 patients at a time. Outcome was evaluated at posttreatment and at a 6-month follow-up. The three treatment groups improved significantly on most outcome measures, whereas the waiting-list control group showed little change. At follow-up, there was a slightly better outcome on vomiting behavior and amount of food consumed in one of the test meals for the exposure plus response-prevention groups relative to the no-exposure group. However, on all other measures, the degree of improvement from pretreatment to follow-up was the same for all three treatment groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
Scholars who study close relationships often measure the same concept with both observational ratings and questionnaire items. In studies where this has been done, the correlations between the two measures have often been low, and one reason may be a "context by measurement" confound. Observational ratings are usually based on behaviors during a specific task, whereas most questionnaire responses are based on a broader context such as "during the past month." In 2001, a total of 292 young couples were videotaped during a discussion task and asked to report on their own behavior and that of their partner during the discussion task and during the past month. The data were configured as a multitrait, multimethod matrix, and the magnitudes of the correlations were estimated with confirmatory factor analysis. The resulting correlations between observer ratings and questionnaire reports of hostile behavior during the videotaped discussion were roughly twice the magnitude of the correlations between observer rating and questionnaire reports during the past month. This suggests that the correspondence between behavioral categories and the content of questionnaire items is greater than previous studies have indicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
Fetal and maternal data were monitored serially at 6 gestational ages from 20 to 38 weeks in 195 Peruvian fetuses. Digitized data included fetal heart rate and motor activity, as well as maternal heart rate and electrodermal conductance. Time series analysis evaluated the development of synchrony in 2 streams of fetal functioning and between mothers and fetuses. Intrafetal synchrony between heart rate and motor activity developed in an orderly fashion, with peak cross-correlation approaching an asymptote at 5 s at 28 weeks. Synchrony was not observed between fetal heart rate and maternal measures. Fetal motor activity exhibited synchrony with both maternal electrodermal and heart rate activity. Implications for revealing fundamental properties of neural development prior to birth are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
The role of arginine vasopressin (AVP) in the nongenomic transfer of paternal behavior from fathers to offspring was examined in Peromyscus. Male California mice (P. californicus) exposed to fewer retrievals by white-footed mouse (P. leucopus) foster parents displayed fewer retrievals of biological offspring. In contrast, white-footed mice were retrieved equally rarely by California mouse foster parents and by biological parents and displayed no changes in pup retrieval behavior. AVP-immunoreactive staining in the bed nucleus of the stria terminalis may predict paternal behavior because it correlated positively with retrievals and with a score consisting of huddling, grooming, and time inside the nest. The authors discuss AVP as a possible mechanism by which early experience shapes adult paternal behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
This study is one of the very few investigating the dioxin body burden of a group of child-bearing-aged women at an electronic waste (e-waste) recycling site (Taizhou, Zhejiang Province) (24 +/- 2.83 years of age, 40% were primiparae) and a reference site (Lin'an city, Zhejiang Province, about 245 km away from Taizhou) (24 +/- 2.35 years of age, 100% were primiparae) in China. Five sets of samples (each set consisted of human milk, placenta, and hair) were collected from each site. Body burdens of people from the e-waste processing site (human milk, 21.02 +/- 13.81 pg WHO-TEQ1998/g fat (World Health Organization toxic equivalency 1998); placenta, 31.15 +/- 15.67 pg WHO-TEQ1998/g fat; hair, 33.82 +/- 17.74 pg WHO-TEQ1998/g dry wt) showed significantly higher levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/ Fs) than those from the reference site (human milk, 9.35 +/- 7.39 pg WHO-TEQ1998/g fat; placenta, 11.91 +/- 7.05 pg WHO-TEQ1998/g fat; hair, 5.59 +/- 4.36 pg WHO-TEQ1998/g dry wt) and were comparatively higher than other studies. The difference between the two sites was due to e-waste recycling operations, for example, open burning, which led to high background levels. Moreover, mothers from the e-waste recycling site consumed more foods of animal origin. The estimated daily intake of PCDD/Fs within 6 months by breastfed infants from the e-waste processing site was 2 times higher than that from the reference site. Both values exceeded the WHO tolerable daily intake for adults by at least 25 and 11 times, respectively. Our results implicated that e-waste recycling operations cause prominent PCDD/F levels in the environment and in humans. The elevated body burden may have health implications for the next generation.  相似文献   
87.
Fluorescein isothiocyanate (FITC)-encapsulated SiO2 core-shell particles with a nanoscale ZnO finishing layer have been synthesized for the first time as multifunctional “smart” nanostructures. Detailed characterization studies confirmed the formation of an outer ZnO layer on the SiO2–FITC core. These ~200 nm sized particles showed promise toward cell imaging and cellular uptake studies using the bacterium Escherichia coli and Jurkat cancer cells, respectively. The FITC encapsulated ZnO particles demonstrated excellent selectivity in preferentially killing Jurkat cancer cells with minimal toxicity to normal primary immune cells (18% and 75% viability remaining, respectively, after exposure to 60 μg/ml) and inhibited the growth of both gram-positive and gram-negative bacteria at concentrations ≥250–500 μg/ml (for Staphylococcus aureus and Escherichia coli, respectively). These results indicate that the novel FITC encapsulated multifunctional particles with nanoscale ZnO surface layer can be used as smart nanostructures for particle tracking, cell imaging, antibacterial treatments and cancer therapy.  相似文献   
88.
89.
Rapid detection of airborne fungal and bacterial spores would enable public agencies to respond quickly and appropriately to intentional releases of hazardous aerosols. Automated analysis of microscope images and automated detection of near-monodisperse peaks in aerosol size distribution data offer complementary approaches to traditional methods for the identification and counting of fungal and bacterial spores. First, spores of the fungus Scopulariopsis brevicaulis were aerosolized in a chamber and then collected with a slit impactor; later, digital microscope images were analyzed manually to determine spore cluster distributions. The images also were analyzed with ImageJ, a program that automatically outlined objects and measured Feret's diameter, area, perimeter, and circularity. These characteristics were used to identify spore clusters automatically using two data analysis methods. Second, a computer program was developed to discriminate near-monodisperse bioaerosol peaks from those for polydisperse ambient particulate matter (PM) and was successfully tested using simulated and real aerosol mixtures. The observed agreement between manual and automated spore counts and the ability to detect spore peaks suggest that it may be possible to develop a system to recognize intentional releases rapidly through examination of particle morphology and size distributions. The peak detection procedure is potentially the fastest technique when used with real-time instrument data, but assumes that intentional releases would consist of large numbers of uniformly sized particles in the respirable size range.

Copyright 2012 American Association for Aerosol Research  相似文献   
90.
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