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111.
Whisman Mark A.; Uebelacker Lisa A.; Bruce Martha L. 《Canadian Metallurgical Quarterly》2006,20(1):164
The prospective association between marital dissatisfaction and alcohol use disorders (abuse and/or dependence) was evaluated in a randomly selected community sample. Married individuals (N=1,675) from the New Haven Epidemiologic Catchment Area project who did not have a current alcohol use disorder at baseline were followed prospectively for 12 months. Results indicated that baseline marital dissatisfaction was significantly associated with alcohol use disorder diagnosis during follow-up, with dissatisfied spouses being 3.7 times more likely than satisfied spouses to have a diagnosis of current alcohol use disorder at follow-up. The longitudinal association between baseline marital dissatisfaction and current alcohol use disorder diagnosis at follow-up remained significant when controlling for baseline demographic variables and history of alcohol use disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
112.
Vogel David L.; Wester Steven R.; Larson Lisa M.; Wade Nathaniel G. 《Canadian Metallurgical Quarterly》2006,37(4):398
Despite the presence of quality mental health care in many communities, people tend to avoid seeking help and wind up languishing in their problems unnecessarily. For the professional to better understand how to reach these individuals, an information-processing model is presented that examines the effects of people's interpretation of their environment and their symptoms on their decision to seek mental health services. Using the model as a guide, suggestions are presented for practitioners who wish to provide services to those who are in need of professional help, yet are hesitant to obtain it. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
113.
Summers Pete; Forehand Rex; Armistead Lisa; Tannenbaum Lynne 《Canadian Metallurgical Quarterly》1998,66(2):327
The relationship between parental divorce occurring during adolescence and young adult psychosocial adjustment was examined, as was the role of family process variables in clarifying this relationship. Participants were young Caucasian adults from divorced (n?=?119) and married (n?=?123) families. Assessments were conducted during adolescence and 6 years later during early adulthood. Young adults from married families reported more secure romantic attachments than those from divorced families; however, differences were not evident in other domains of psychosocial adjustment after demographic variables were controlled. Three family process variables (parent–adolescent relationship, interparental conflict, and maternal depressive symptoms) were examined as potential mediators and moderators of the association between parental divorce and young adult adjustment. No evidence supporting mediation or moderation was found; however, the parent–adolescent and parent–young adult relationships, particularly when the identified parent was the father, emerged as significant predictors of young adult psychosocial adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
114.
LeFevre Jo-Anne; Bisanz Jeffrey; Daley Karen E.; Buffone Lisa; Greenham Stephanie L.; Sadesky Gregory S. 《Canadian Metallurgical Quarterly》1996,125(3):284
Researchers have assumed that adults solve simple arithmetic problems by retrieving answers from a network of stored facts. In 2 studies, undergraduates described their solutions of single-digit multiplication problems. They reported direct retrieval on approximately 80% of trials but also reported rules (e.g., anything times 0 is 0), repeated addition (e.g., 2?×?4?=?4?+?4), number series (e.g., 3?×?5?=?5, 10, 15), and derived facts (e.g., 6?×?7?=?[6?×?6]?+?6). Participants were slower to retrieve problems that were most likely to be solved by nonretrieval procedures and faster to retrieve problems that were usually solved by retrieval. These results indicate that direct-retrieval models are incomplete accounts of adults' performance and support a continuing influence of learning and experience on the mental representation of simple multiplication problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
115.
In a study with 133 children in Grades 1, 3, and 5, a brief training procedure designed to improve performance on the Children's Embedded Figures Test, a test of visual ability, resulted in significant improvement for girls but not for boys. No sex difference was observed among children receiving this training. The implications for theories of sex differences in visual–spatial ability are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
116.
Glutamate receptors play a major role in neural cell plasticity, growth, and maturation. The degree to which ionotropic glutamate
receptors (iGluR) conduct current is dependent on binding of extracellular ligands, of which glutamate is the native agonist.
Although the glutamate binding site of the GluR2 class of amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) iGluR
has been structurally characterized, the allosteric sites attributed to neurosteroid binding have yet to be localized. Here,
using intrinsic tryptophan fluorescence spectroscopy, we show that the extracellular glutamate binding core of the GluR2 class
of AMPA receptors also binds to two neurosteroids, pregnenolone sulfate (PS) and 3α-hydroxy-5β-pregnan-20-one sulfate, both
of which negatively modulate its activity. Interest in these sulfated neurosteroids stems from their differential modulation
of other members of the iGluR family and their potential use as endogeneous agents for stroke therapy. In particular, whereas
PS inhibits AMPA and other non-N-methyl-d-aspartate (NMDA) family members, it activates the NMDA receptor. In addition to providing evidence for binding of these neurosteroids
to the glutamate binding core of the GluR2 class of AMPA receptors, our data suggests that both neurosteroids bind in a similar
manner, consistent with their modulation of activity of this class of iGluR. Interestingly, the conformational change induced
upon binding of these neurosteroids is distinct from that induced upon glutamate binding. 相似文献
117.
Poyneer LA Macintosh B 《Journal of the Optical Society of America. A, Optics, image science, and vision》2004,21(5):810-819
Adaptive optics (AO) systems take sampled measurements of the wave-front phase. Because in the general case the spatial-frequency content of the phase aberration is not band limited, aliasing will occur. This aliasing will cause increased residual error and increased scattered light in the point-spread function (PSF). The spatially filtered wave-front sensor (SFWFS) mitigates this phenomenon by using a field stop at a focal plane before the wave-front sensor. This stop acts as a low-pass filter on the phase, significantly reducing the high-spatial-frequency content phase seen by the wave-front sensor at moderate to high Strehl ratios. We study the properties and performance of the SFWFS for open- and closed-loop correction of atmospheric turbulence, segmented-primary-mirror errors, and sensing with broadband light. In closed loop the filter reduces high-spatial-frequency phase power by a factor of 10(3) to 10(8). In a full AO-system simulation, this translates to a reduction by up to 625 times in the residual error power due to aliasing over a specific spatial frequency range. The final PSF (generated with apodization of the pupil) has up to a 100 times reduction in intensity out to lambda/2d. 相似文献
118.
Zhong WH Li J Xu LR Michel JA Sullivan LM Lukehart CM 《Journal of nanoscience and nanotechnology》2004,4(7):794-802
Processing methods have been optimized for the formation of graphitic carbon nanofiber (GCNF)/epoxy nanocomposites containing GCNFs highly dispersed throughout a thermoset epoxy matrix. GCNFs having a herringbone atomic structure are surface-derivatized with bifunctional hexanediamine linker molecules (GCNF-HDA) capable of covalent binding to an epoxy matrix during thermal curing and are cut to smaller dimension using high-power ultrasonication. GCNF-HDA nanofibers are dispersed in epoxy resin at 0.3 wt.% loading using variable levels of ultrasonication processing prior to thermal curing. Effects of sonication power on the quality of the GCNF-HDA/epoxy material obtained after curing have been determined from flexural property measurements, thermomechanical analysis and SEM/TEM imaging. GCNF-HDA/epoxy material of the highest quality is obtained using low-power sonication, although high-power sonication for short periods gives improved flexural properties without lowering the glass transition temperature. Good dispersion and polymer wetting of the GCNF component is evident on the nanoscale. 相似文献
119.
Mercury in humans and other top predators living in the Arctic is present at elevated levels. Since only methylmercury (MeHg) bioaccumulates in food chains, sources of MeHg need to be identified. Recently, wetlands in the High Arctic were found to produce MeHg, and this was confirmed in laboratory soil incubations. In the present study both wetlands and snowmelt water were evaluated as sources of MeHg to Arctic ecosystems in Nunavut. Three substudies took place on Cornwallis Island, and one took place on Ellesmere Island. First, the effect of wetland presence in lake watersheds was evaluated by comparing four lakes with wetlands present to four lakes without wetlands present. Next, two individual wetlands were spatially and temporally investigated. Finally, three basin tributaries were evaluated for snowmelt MeHg sources. Catchments on Cornwallis Island with wetlands did not have an observable effect on MeHg levels in downstream lake water, but the wetland on Ellesmere Island contributed significant MeHg. In contrast, calculated yields of MeHg in tributaries draining snowmelt on Cornwallis Island were higher (ca. 1.5 mg km(-2) day(-1)) than those measured in temperate catchments characterized by wetlands. Methylmercury and total Hg concentrations in lakes, wetlands, and basin tributaries showed a strong temporal trend that corresponded to inputs from snowmelt water in late spring. This study revealed that wetland export of MeHg to downstream Arctic lakes is site dependent, and snowmelt water was the most significant source of MeHg to Arctic ecosystems located on Cornwallis Island. 相似文献
120.
Immobilized enzyme systems are important in a broad range of applications, from biological sensing to the industrial-scale biocatalytic synthesis of chiral products. We demonstrate the ability to systematically vary and quantitatively assess the immobilization capacity of porous silicon thin films for the enzyme glutathione-S-transferase in a manner predicted by a simple geometric model of the porous silicon matrix. We find that the immobilization capacity quantatitively correlates with systematic changes in the device thickness. These results are significant since, despite the wide range over which porous silicon morphology and surface area can be varied, few attempts have been made to systematically characterize surface binding capacity. Our findings suggest that porous silicon can be an ideal matrix, where immobilization of a predictable quantity of biological material is desired. 相似文献