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The Journal of Supercomputing - In this paper, we propose a parallel source separation system designed to extract heart and lung sounds from single-channel mixtures. The proposed system is based on...  相似文献   
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Women are approximately twice as likely as men to develop posttraumatic stress disorder (PTSD), but the cause of this disparity remains unclear. This study evaluated 2 alternative explanations of gender differences in PTSD, one pointing to an intrinsic vulnerability in women and the other emphasizing sexual violence across the life span. To test these competing theories, the authors analyzed National Violence Against Women Survey data from 591 victims of partner aggression. Results suggested that gender, when considered alone, has a small but significant effect on PTSD symptom severity. However, once models factor in sexual victimization history, the latter replaces gender as a key determinant of PTSD symptoms. These findings argue against theories of "feminine vulnerability," instead linking PTSD risk to sexually violent situations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This work deals with carrier-facilitated membrane transport of Au(III) from chloride media across a polymer-immobilised liquid membrane (PILM) using as organic reagents N-(thiocarbamoyl)benzamide derivatives and N-benzoylthiourea derivatives, denoted as 2a–c and 3a–f, respectively. Both the composition of the organic membrane solvent and the type of carrier have a marked effect on gold permeation. Recovery and permeability of gold using 2a–c and 3a–f across a PILM proceed in the following order: 3e≈3d≈3c?3f>3b≈3a≈2a≈2b≈2c. In view of the performance of these carriers, 3c was selected as a metal receptor for detailed studies of Au(III) in permeation. A model is presented for the permeation of Au(III) (61 μM) in 0.5 M Cl at pH 2.5 using 3c as a membrane carrier. The mathematical equations describing the rate of permeation are derived to correlate the membrane permeability coefficient with diffusional and equilibrium parameters. The mass transfer coefficient was calculated from the described model as 1.1×10−5 m s−1, and the thickness of the aqueous boundary was later calculated to be 65 μm. Several polymeric supports were tested for impregnation of the organic extractant, and Durapore (Millipore) afforded the maximum flux for Au(III), yielding a value of 1.1×10−14 mol m−2 s. The relationship between flux and support characteristics is derived and a mathematical equation is presented. Of the several diluents used, cumene had the most satisfactory performance in terms of PILM stability and metal transport. Of the different reagents used, 0.5 M sodium thiocyanate in 0.5 M NaCl at pH 2.5 served most efficiently as the stripping agent. More than 80% of the Au(III) could be readily separated using 3c in the presence of various metals such as Cu(II), Fe(III) and Zn(II).  相似文献   
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Passive remediation consists of a permeable system that enables the water to pass through while retaining metals by means of biogeochemical reactions. Conventional passive treatments are based on calcite dissolution. This increases the pH to values between 6 and 7, which are insufficiently high to precipitate divalent metals. Alternative treatments are based on sulfate reduction with organic matter in order to precipitate metal sulfides. However, redox reactions are usually too slow to treat large groundwater flows as currently found in gravel aquifers (>50 m/a). Caustic magnesia obtained from calcination of magnesium carbonate was tested as an alternative material to devising passive remediation systems. Caustic magnesia reacts with water to form magnesium hydroxide, which dissolves, increasing the pH to values higher than 8.5. Then zinc and lead are mainly precipitated as hydroxides, copper is precipitated as hydroxysulfate, and manganese(II) is oxidized and precipitated as manganese(III) oxides. Thus, metal concentrations as high as 75 mg/L in the inflowing water are depleted to values below 0.04 mg/L. Magnesia dissolution is sufficiently fast to treat flows as high as 100 m/a. The new precipitates may lead to a permeability drop in the porous treating system. Mixtures of caustic magnesia and an inert material such as silica sand (approximately 50% of each) have been shown to be as reactive as pure magnesia and permeable for a longer time (more than 10 months and 1000 pore vol).  相似文献   
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The authors investigated coping responses to sexual harassment across 4 samples of working women from 3 cultures and 2 occupational classes. Complete-link cluster analyses provide preliminary support for D. E. Knapp, R. H. Faley, S. E. Ekeberg, and C. L. Z. Dubois's (1997) coping framework, suggesting that avoidance, denial, negotiation, advocacy seeking, and social coping are universal responses to sexual harassment. Further, L. F. Fitzgerald's (1990) internal-extemal dichotomy appears to capture higher order relationships among coping responses. In addition, regression analyses suggest that Turkish and Hispanic American women engage in more avoidance than Anglo American women, and Hispanic women also use more denial but less advocacy seeking. No differences emerged in social coping. The authors discuss these results in the context of coping theory, individualism-collectivism, power distance, and patriarchal gender norms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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BACKGROUND: Sorption of polycyclic aromatic hydrocarbons (PAHs) on activated carbon and the Macronet polymeric sorbent MN200 was investigated to determine the effectiveness of each sorbent for removal of pollutants from aqueous solution and their possible use as sorbent materials for groundwater. Experiments were carried out to determine the loading capacities of a family of PAHs (acenaphthene, anthracene, fluoranthene, fluorene, naphthalene and pyrene). RESULTS: Activated carbon was the more effective sorbent, with maximum loadings of PAHs between 90 and 230 g kg?1, while MN200 resin showed values of 25–160 g kg?1. Loading isotherms based on the Langmuir, Freundlich and Redlich–Peterson models were determined. The hydrophobic character of the pollutants appeared as an important parameter related to the sorption process. Equilibrium and kinetic parameters were used to determine the retardation factors for each PAH. CONCLUSION: The calculated values for the simulation of barrier thickness using both sorbents, taking into account EU requirements for PAHs in groundwater effluent, were perfectly reasonable as a first estimate. The better kinetic properties of MN200 are evident in lower hydraulic residence times and consequently in a lower barrier thickness. Copyright © 2008 Society of Chemical Industry  相似文献   
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This article examined the relationships and outcomes of behaviors falling at the interface of general and sexual forms of interpersonal mistreatment in the workplace. Data were collected with surveys of two different female populations (Ns=833 and 1,425) working within a large public-sector organization. Findings revealed that general incivility and sexual harassment were related constructs, with gender harassment bridging the two. Moreover, these behaviors tended to co-occur in organizations, and employee well-being declined with the addition of each type of mistreatment to the workplace experience. This behavior type (or behavior combination) effect remained significant even after controlling for behavior frequency. The findings are interpreted from perspectives on sexual aggression, social power, and multiple victimization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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