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In this article the author reviews research evidence on the prevalence of mental disorders in lesbians, gay men, and bisexuals (LGBs) and shows, using meta-analyses, that LGBs have a higher prevalence of mental disorders than heterosexuals. The author offers a conceptual framework for understanding this excess in prevalence of disorder in terms of minority stress--explaining that stigma, prejudice, and discrimination create a hostile and stressful social environment that causes mental health problems. The model describes stress processes, including the experience of prejudice events, expectations of rejection, hiding and concealing, internalized homophobia, and ameliorative coping processes. This conceptual framework is the basis for the review of research evidence, suggestions for future research directions, and exploration of public policy implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The effect of sodium azide at concentrations of 0.02% on three carbohydrate assay methods was investigated: it reduced the sensitivity of the phenol-sulfuric acid method for aldoses by 30–35%; the m-hydroxydiphenyl and orcinol methods for galacturonic acid became insensitive. At this level of azide the sensitivity of the orcinol method for neutral sugar, but not for galacturonic acid, could be partially restored by increasing the amount of orcinol in the reaction mixture. The antimicrobial agent thimerosal did not interfere with the phenol-sulfuric acid or m-hydroxybiphenyl methods; with the orcinol method it interfered with the determination of galacturonic acid. This latter problem can be overcome by measuring the absorbance at longer wavelengths or correcting the measurements by an appropriate blank value.  相似文献   
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Galactosyltransferase specific activities in embryonic chick retina, optic tectum, and telencephalon were found to decline during embryonic development. Incorporation of galactose from nucleotide sugar into exogenously added glycoprotein acceptor was measured in the presence of excess of glycoprotein acceptor. This ensured that the specific activity measurements were reflections of tru enzyme specific activity rather than availability of acceptor. Moreover, we have shown that the decline in specific activity is not due to degradation of the nucleotide sugar, UDP-galactose, under our in vitro assay conditions. Enzymatic specific activity declined sharply with embryonic age for all tissues tested. This decline was not affected by the presence of 5-bromodeoxyuridine during in vitro culture of embryonic chick neural retina above that caused by the culturing alone. Galactosyltransferase activity was not found to be associated with the plasma membrane fraction from homogenized tissue but rather with the microsomal fraction. Thus, the changes in galactosyltransferase specific activity detected here do not reflect changes at the cell surface.  相似文献   
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Semiconducting-ionic membranes (SIMs) have exhibited significant superiority to replace the conventional ionic electrolytes in solid oxide fuel cells (SOFCs). One interesting phenomenon is that the SIMs can successfully avoid the underlying short-circuiting issue and power losses while bringing significantly enhanced power output. It is crucial to understand the physics in such devices as they show distinct electrochemical processes with conventional fuel cells. We first presented experimental studies of a SIM fuel cell based on a composite of semiconductor LiCo0.8Fe0.2O2 (LCF) and ionic conductor Sm-doped CeO2 (SDC), which achieved a remarkable power density of 1150 mW cm?2 at 550 °C along with a high open circuit voltage (OCV) of 1.04 V. Then, for the first time we used a physical model via combining a semiconductor-ionic contact junction with a rectifying layer which blocks the electron leakage to describe such unique SIM device and excellent performance. Current and power are the most important characteristics for the device, by introducing the rectifying layer we described the SIM physical nature and new device process. This work presented a new view on advanced SIM SOFC science and technology from physics.  相似文献   
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Electric vehicles (EVs) present efficiency and environmental advantages over conventional transportation. It is expected that in the next decade this technology will progressively penetrate the market. The integration of plug-in electric vehicles in electric power systems poses new challenges in terms of regulation and business models. This paper proposes a conceptual regulatory framework for charging EVs. Two new electricity market agents, the EV charging manager and the EV aggregator, in charge of developing charging infrastructure and providing charging services are introduced. According to that, several charging modes such as EV home charging, public charging on streets, and dedicated charging stations are formulated. Involved market agents and their commercial relationships are analysed in detail. The paper elaborates the opportunities to formulate more sophisticated business models for vehicle-to-grid applications under which the storage capability of EV batteries is used for providing peak power or frequency regulation to support the power system operation. Finally penetration phase dependent policy and regulatory recommendations are given concerning time-of-use pricing, smart meter deployment, stable and simple regulation for reselling energy on private property, roll-out of public charging infrastructure as well as reviewing of grid codes and operational system procedures for interactions between network operators and vehicle aggregators.  相似文献   
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Slab waveguides were constructed in K(1-x)Li(x)Ta(1-y)Nb(y)O(3) crystals by the implantation of (12)C(+4) ions at 30 MeV and (16)O(+5) ions at 30 and 40 MeV. The waveguides were characterized by a prism coupler setup. A refractive index drop of 10.9% was observed in a layer formed by the implantation of (16)O(+5) ions at 30 MeV. The carbon-implanted waveguides were found to be thermally stable after annealing at 450 degrees C. A semiempirical formula for predicting the change in the refractive index given the parameters of the implantation process was developed. It is argued that the combination of the basic implantation process with the semiempirical formula can be developed to become a generic method for constructing complex electro-optic circuits with a wave-guided architecture.  相似文献   
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The scanning electrochemical microscope (SECM) is one of the scanning probe techniques that have been developed following the introduction of the scanning tunneling microscope. The approaches that have been used to modify surfaces with lateral resolution using the SECM are presented and discussed. These approaches made it possible to drive a variety of microelectrochemical reactions on surfaces, as well as to study the mechanism of these processes due to the unique advantages that the SECM offers.  相似文献   
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