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151.
An ongoing longitudinal community study (N?=?375) examined childhood risks and later adult impairments associated with 1-year Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) diagnoses of major depression during the transition to adulthood. Risks from birth to age 9 were reported by mothers, participants, and teachers. Teacher-reported hostility at age 6 predicted later depression. At age 9, self-perceptions of anxiety/depression, unpopularity, familial rejection, and abuse were potent risks. For men, neonatal and childhood health problems predicted later depression. For women, risks included family constellation, parental death, and poor academic achievement at age 9. Men and women who were depressed at age 18, age 21, or both demonstrated extensive psychosocial impairments in early adulthood, including poor overall functioning, interpersonal and behavioral problems, low self-esteem, and suicidality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
152.
Editorial     
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153.
In a 4-wave, 2-year longitudinal design, the authors obtained measures of negative affect (NA) and self-perceived competence from 220 boys and 216 girls who were 7th graders at the beginning of this study. NA was operationalized as the common dimension underlying self-reports of depressive symptoms, anxiety symptoms, and negative emotions. Self-perceived competence consisted of 2 higher order constructs: a well-behaved/good-student factor and an attractive/athletic/popular factor. Structural equation modeling revealed very high stability estimates for all constructs. Nevertheless, self-perceived competence in the attractive/athletic/popular domain predicted changes in NA. Conversely, NA predicted changes in self-perceived competence in the well-behaved/good-student domain. The primacy of NA versus self-cognitions depends, in part, on the type of self-cognitions being examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
154.
Summary Poly-p-trimethylsilylphenylmethacrylate(75)-co-glycidylmethacrylate (25) containing aromatic bisazides exhibits uv sensitivity as a negative type photoresist. Sensitometric data have been evaluated. The pressure-dependant reactivity under the conditions of oxygen reactive ion etching was determined.  相似文献   
155.
Architecture of field-programmable gate arrays   总被引:8,自引:0,他引:8  
A survey of field-programmable gate array (FPGA) architectures and the programming technologies used to customize them is presented. Programming technologies are compared on the basis of their volatility, size parasitic capacitance, resistance, and process technology complexity. FPGA architectures are divided into two constituents: logic block architectures and routing architectures. A classification of logic blocks based on their granularity is proposed, and several logic blocks used in commercially available FPGAs are described. A brief review of recent results on the effect of logic block granularity on logic density and performance of an FPGA is then presented. Several commercial routing architectures are described in the context of a general routing architecture model. Finally, recent results on the tradeoff between the flexibility of an FPGA routing architecture, its routability, and its density are reviewed  相似文献   
156.
A series of AgCuO2 samples are prepared and tested as alkaline cathode materials for primary batteries. AgCuO2 discharges via four equivalent-charge reduction processes, the rate capabilities of which are determined. At ambient temperature AgCuO2 displays superior rate capabilities for the two highest voltage processes. For all samples, the rate capability of the two lower voltage processes is always superior to those at higher voltage. This is due to the electrode intrinsically doping itself with elemental silver during discharge as part of the second reduction process. The electrode compares favourably with commercial electrolytic manganese dioxide but is prone to self-discharge, the kinetics of which are also discussed.  相似文献   
157.
158.
A feature-based method that determines the thickness and electrical conductivity of a coating on a metal plate from the change in the frequency-dependent impedance of an eddy-current probe coil is presented. Recently a least-squares solution of this problem was presented, which, however, requires approximately 20 CPU minutes on a DEC 5000 work station for the analysis of each set of measurements. We show that a feature-based approach can reduce the time to a few seconds on the same processor. We start by showing that a three-parameter scaling of the resistive component of the impedance change vs. frequency leads to a simple and nearly universal curve. Consequently these parameters provide a simple and compact way of expressing the data. Next, we show that the three scaling parameters can be used to construct a look-up table that determines the conductivity and thickness of the coating. Finally, we test the method using experimental data.  相似文献   
159.
Data from the literature, as well as our previous work, indicate a protective effect of superoxide dismutase (SOD) in topical application against UV-induced cutaneous damage. In the present article we show that pre-treatment of the skin with SOD protects against PUVA-induced inflammatory reactions not only in murine, but also in human skin. Using fluorescently labelled Cu,Zn SOD, epifluorescence microscopy and digital image processing, we demonstrate that the FITC fluorescence localizes in the stratum corneum and upper granulosa, as well as in the epidermal cell layer surrounding the lumina of the hair follicles. These findings were similar for murine and human skin. Since autofluorescence was eliminated by a special filter, it can be ascertained that the fluorescence observed in the tissues was due to FITC-labelled SOD.  相似文献   
160.
A rat milk substitute containing lower amounts of palmitic and oleic acid in the triacylglycerols in comparison to natural rat milk was fed to artificially reared rat pups from day 7 after birth to day 14. Pups reared by their mother served as controls. Free trideuterated (D3) palmitic acid [(C2H3)(CH2)14COOH, 98 atom % D] and free perdeuterated (D31) palmitic acid [C15 2H31COOH, 99 atom % D] in equal quantity were mixed into the triacylglycerols of the milk substitute in an amount equal to 100% of the palmitic acid in the triacylglycerols. A control milk substitute contained unlabeled free palmitic acid in an amount equal to 100% of the palmitic acid in the triacylglycerols of the milk substitute. The objective was to determine if palmitic acid in the diet contributed significantly to the palmitic acid content of developing brain and other organs. The methyl esters of the fatty acids were analyzed by gas chromatography and the palmitic acid methyl ester was examined by fast atom bombardment mass spectrometry. The proportion of deuterated methyl palmitate as a percentage of total palmitate was determined; 32% of the palmitic acid in liver and 12% of the palmitic acid in lung were trideuterated and perdeuterated palmitic acid in approximately equal amounts. The brain, by contrast, did not contain the deuterated palmitic acid moiety. Quantitation of palmitic acid and total fatty acids revealed a significant accumulation in organs in the interval from 7 to 14 days of age. Under our experimental conditions, labeled palmitic acid does not enter the brain. Consequently, we conclude that the developing brain produces all required palmitic acid byde novo synthesis.  相似文献   
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