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361.
Hobfoll Stevan E.; Canetti Daphna; Hall Brian J.; Brom Danny; Palmieri Patrick A.; Johnson Robert J.; Pat-Horenczyk Ruth; Galea Sandro 《Canadian Metallurgical Quarterly》2011,23(3):599
We evaluated the accuracy of posttraumatic stress disorder (PTSD) and major depression (MD) diagnoses using brief assessment instruments conducted by phone. PTSD and MD were assessed by telephone interview in a randomly selected sample of Jewish and Palestinian residents of Jerusalem (N = 150) during a period of marked threat of terrorism and war. We utilized the PTSD Symptom Scale Interview Format (Foa, Riggs, Dancu, & Rothbaum, 1993) and the Patient Health Questionnaire—9 (PHQ–9; Kroenke, Spitzer, & Williams, 2001). We then conducted in-depth, in-person interviews within 2 weeks, assessing PTSD and MD using the Composite International Diagnostic Interview (CIDI; Kessler et al., 2004). The prevalence of PTSD and MD diagnosis ascertained by the 2 assessment modalities was similar. Indices of classification accuracy for the phone interview, using the in-person interview as the standard, ranged from modest to high. Brief phone and in-depth in-person measures of PTSD and MD also correlated similarly with other demographic, stress, and coping factors, suggesting convergent validity. Brief phone interviews appear useful for estimating the prevalence of psychological disorders in mass casualty contexts and may have a critical role in both epidemiologic work and guiding public health interventions. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
362.
363.
A procedure to obtain realistic geometric models of foods having different inner tissues or sub-regions is developed. The proposed methodology consists in colour segmentation of food images using a distance criterion, obtaining a reduced set of pixels representing univocally all boundaries of food sub-regions, and finally construction of the geometric model through linear interpolation. The procedure was applied to samples of different nature and complexity. The geometric models were assessed in two different ways, i.e. evaluating the performance of the image segmentation step and simulating a chilling process. The former provided an objective assessment while the later verified the usefulness of the geometric models. An optimized scenario was found between the approximation degree of the food boundaries and the computational resources involved in process simulation. Furthermore, the presented procedure can be used to perform food quality evaluation. 相似文献
364.
S. Turchetta 《The International Journal of Advanced Manufacturing Technology》2012,61(5-8):441-448
Stone machining by diamond tool is a widespread process to manufacture both standard products, such as tiles, slabs, kerbs, and so on, and design shapes. Cutting force and energy may be used to monitor stone machining. Empirical models are required to guide the selection of cutting conditions. In this paper, the effects of cutting conditions on cutting force and cutting energy are related to the shape of the idealized chip thickness. These effects are put into relationship with the diamond tool wear too. The empirical models developed in this paper can be used to predict the variation of the cutting energy. Therefore these models can be used to guide the selection of cutting conditions and to predict when it is needed to change the tool. The chip generation and removal process has been quantified with the intention of assisting both the toolmaker and the stonemason in optimizing the tool composition and cutting process parameters, respectively. 相似文献
365.
Arianna Gambirasi Sandro Cattarin Marco Musiani Lourdes Vázquez-Gómez Enrico Verlato 《Electrochimica acta》2011,(24):8582
A method for decorating the surface of disk electrodes with metal nanowires is presented. Cu and Ni nanowires with diameters from 1.0 μm to 0.2 μm are directly deposited on the electrode surface using a polycarbonate membrane filter template maintained in contact with the metal substrate by the soft homogeneous pressure of a sponge soaked with electrolyte. The morphologic and structural properties of the deposit are characterized by scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The latter shows that the head of nanowires with diameter of 0.4 μm is ordinarily polycrystalline, and that of nanowires with diameter of 0.2 μm is almost always monocrystalline for Cu and frequently also for Ni. Cyclic voltammetries and impedance investigations recorded in alkaline solutions at representative Ni electrodes decorated with nanowires provide consistent values of roughness factor, in the range 20–25. 相似文献
366.
Harald Hetzner Jens Schaufler Stephan Tremmel Karsten Durst Sandro Wartzack 《Surface & coatings technology》2012
A diamond-like carbon (DLC) coating with a top layer of pure hydrogenated amorphous carbon (a-C:H) and an interlayer of tungsten-modified hydrogenated amorphous carbon (a-C:H:W) was deposited onto polished cylindrical specimens of a hardened and tempered cold work tool steel. On a load-scanning test rig, tribological–mechanical tests under dry conditions with DLC coated specimens sliding against identical, but uncoated specimens were performed. Additionally, comparative tests with DLC sliding against DLC and tool steel sliding against tool steel were carried out. During each test cycle, the normal load was gradually increased from 13 to 350 N, corresponding to a Hertzian contact pressure of 1.0 to 3.0 GPa. The coefficient of friction was monitored as a function of the normal load, with a significant increase in friction indicating failure of the coating. The tests were repeated and stopped at different total numbers of load cycles. After the tests, a FIB-assisted microscopical analysis in terms of wear and damage of the DLC coating was performed, revealing the (subsurface) failure mechanisms. For DLC sliding against steel, the coating fails within only few load cycles; first tribologically and after that mechanically. Failure is initiated by adherence and subsequent transfer of steel of the counter body. Below adhered steel flakes, tensile cracks form in the a-C:H top layer, with sharp crack edges removing even more steel from the counter body. In following load cycles, coating fragments are being pulled out at these spots, representing the final failure mode. In contrast, for DLC sliding against DLC, no coating failure and also no significant wear are observed, even after a considerably higher number of load cycles. 相似文献
367.
The members of the genus Clostridium, including the spore-forming anaerobic bacteria, have a complex and strictly regulated life cycle, but very little is known about the genetic pathways involved in the different stages of their life cycle. Clostridium sporogenes, a Gram-positive bacterium usually involved in food spoilage and frequently isolated from late blowing cheese, is genetically indistinguishable from the proteolytic Clostridium botulinum. As the non-neurotoxic counterpart, it is often used as an exemplar for the toxic subtypes. In this work, we performed a microscopic study combined with a custom array-based analysis of the C. sporogenes cycle, from dormant spores to the early stationary phase. 相似文献
368.
369.
Sandro D.B. Bitar Carlos T. da Costa Junior José A.L. Barreiros João C. do L. Neto 《Energy Policy》2009
This paper examines some problems encountered in the expansion of isolated electrical systems (IES) in the Amazon region, more precisely, the thermoelectric systems used in that region. Supposing a certain degree of uncertainty in energy consumption, we evaluate the expansion of thermoelectric power from firewood and diesel fuel, together with variations for costs, CO2 emissions, and number of direct jobs (NDJ) generated with the use of these technologies. The analysis is accomplished by using fuzzy multi-objective mathematical programming, and interpreting each objective function both by itself and in combination with the others, through a fuzzy multi-objective parametrization. The scenarios are defined by the energy consumption percentage increase, limited to be below some admissible maximum value, while still considering variations in the installed power. The costs, CO2 emission, and the NDJ generated are analyzed and compared with the largest values obtained with the model of crisp mathematical programming, used for the original configuration. Finally, in Section 4, we present the results and respective analyses for the finished simulation. 相似文献
370.
The heterogeneous oxidation of cyclooctene with hydrogen peroxide catalyzed by manganese 5,10,15,20‐tetrakis(2′,6′‐dichlorophenyl)porphyrinate, in the presence of hexafluoroacetone hydrate as co‐catalyst, has been studied in supercritical carbon dioxide, at 40 °C and 20 MPa. Under proper conditions, a complete olefin conversion may be obtained with the formation of cyclooctene oxide as the sole product. Fixation by hexafluoroacetone into its perhydrate derivatives provides a useful system to solubilize hydrogen peroxide in supercritical carbon dioxide, and to hamper catalyst bleaching and oxidant decomposition. Moreover, in the presence of both manganese‐porphyrin and hexafluoroacetone, the reaction rates are enhanced. Among the factors that may increase yields and rate of conversion, the use of a Teflon‐coated steel reactor rather than an uncoated one proved to be quite relevant, thus indicating the occurrence of a parasite radical decomposition of hydrogen peroxide promoted by steel reactor walls. 相似文献