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Risk factors affecting the course of posttraumatic stress disorder (PTSD) are poorly understood. As part of a larger study on characterizing exposure to herbicides in Vietnam, the authors investigated this issue in a random sample of 1,377 American Legionnaires who had served in Southeast Asia during the Vietnam War and were followed over a 14-year period. High combat exposure, perceived negative community attitudes at homecoming, minority race, depression symptoms at Time 1, and more anger at Time 1 predicted a more chronic course. Community involvement at Time 1 was protective and associated with decreased risk at Time 2. Discomfort in disclosing Vietnam experiences was associated with an increased risk for developing PTSD but did not predict its course. Combat exposure predicted PTSD course more strongly than any other risk factor. Findings suggest recovery from PTSD is significantly influenced by perceived social support. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Inkjet printing has been used to produce resonant radio frequency coils that are comparable to those produced by conventional printed circuit board (PCB) methods. The coils, which consist of a conductive loop and in-series capacitors, form part of a receiver circuit that is used for magnetic resonance imaging (MRI). The resonant circuit is selective at the predetermined frequency of 400 MHz. The required electrical components (resistor, capacitor, and inductor) were produced by inkjet printing, with scaling experiments for resistor and capacitor performed before the complete loops with integrated capacitors were printed. Numerical simulation was used to determine the required values for the components. The inkjet printed circuit was combined with a small tuning and matching board before being connected to a network analyzer and the MRI hardware. With a matching of ${-}$ 38 dB at 400 MHz the achieved results were comparable to those from standard PCB techniques. The performance of the inkjet printed component as a receiver device for nuclear magnetic resonance and MRI was verified by imaging reference phantoms and a whole kiwifruit; it compares favorably to standard MRI devices. Inkjet printing can, therefore, be considered a feasible technique for producing MRI receiver circuits on flexible substrates.   相似文献   
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Meningeal worm (Parelaphostrongylus tenuis) is a neurotropic nematode of ungulates in eastern North America. Lack of an effective diagnostic test increases the concern of translocating potentially infected ungulates into western North America, where P. tenuis does not occur naturally. In an attempt to identify serodiagnostic molecules, we determined (1) whether elk (Cervus elaphus) experimentally infected with P. tenuis produce antibodies against infective larvae or adult worms, and (2) if sera consistently recognize antigens that distinguish P. tenuis from a common nematode parasite of elk, the lungworm Dictyocaulus viviparus. Each of 10 elk were exposed to 15 or 300 infective P. tenuis larvae. Serum was collected (0, 41, and 83 days post-exposure and at necropsy) and monitored for antibodies using the enzyme-linked immunosorbent assay (ELISA) and immunoblot. When reactivity of sera with larval P. tenuis protein was compared (day 0 versus 83), ELISA values were significantly higher on day 83 for elk exposed to 15 or 300 parasites. Likewise, ELISA values using protein of adult P. tenuis were higher for elk exposed to 300 larvae. Immunoblots showed that sera from elk, with adult worms in the central nervous system, consistently recognized the 25-27, 28-30, and 34-36 kDa antigens of infective larvae after 83 days. However, many D. viviparus molecules were found to cross-react with antibodies formed against meningeal worm antigens. Use of adult worm proteins for serodiagnosis appears limited, because no protein was consistently recognized by sera collected from elk exposed to 15 larvae. We believe that development of a reliable diagnostic test for meningeal worm requires more research addressing cross-reactivity and detection of P. tenuis during the incubation stage.  相似文献   
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The Waelz process is a classic method for treating steel plant dusts containing zinc and lead. This process makes especially exacting demands on the off-gas cleaning system because, in most cases, the feed material is heavily contaminated with organic and inorganic components. As a result of the thermal treatment of the residues, dioxins and furans are liberated on the raw-gas side, requiring the installation of additional off-gas cleaning systems. Using as examples two Waelz kiln plants, this article describes the primary measures that minimize the formation of dioxins and furans. Formore information, contact K. Mager, Nordag AG, Cologne, Germany; e-mail kmager@bus-ag.de.  相似文献   
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Single-channel activities were observed in outside-out patches excised from oocytes expressing a mammalian 5-hydroxytryptamine (5-HT) transporter. Channel conductance was larger for a mutant in which asparagine177 of the third putative transmembrane domain was replaced by glycine, suggesting that this residue lies within or near the permeation pathway. The N177G mutant enables quantitative single-channel measurements; it displays two conducting states. One state, with conductance of approximately 6 pS, is induced by 5-HT and is permeable to Na+. The other state (conductance of approximately 13 pS) is associated with substrate-independent leakage current and is permeable to both Na+ and Li+. Cl- is not a major current carrier. Channel lifetimes under all conditions measured are approximately 2.5 ms. The single-channel phenomena account for previously observed macroscopic electrophysiological phenomena, including 5-HT-induced transport-associated currents and substrate-independent leakage currents. The channel openings occur several orders of magnitude less frequently than would be expected if one such opening occurred for each transport cycle and therefore do not represent an obligatory step in transport. Nevertheless, single-channel events produced by neurotransmitter transporters indicate the functional and structural similarities between transporters and ion channels and provide a new tool, at single-molecule resolution, for detailed structure-function studies of transporters.  相似文献   
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The limited aperture problem of physical optics inverse scattering is examined via the method of multidimensional stationary phase. It is shown that target information is recoverable from bandlimited and aspect-limited scattering data. Numerical examples are presented for the case of a perfectly reflecting circular cylinder.  相似文献   
8.
Nephelometric turbidity is an optical index for the side scattering of light caused by fine particles suspended in water. When a mixed composition of suspended inorganic and organic materials, including dissolved organic material, is present, turbidity measurements can be affected by the different optical properties of the organic and inorganic materials present, and different turbidimeters are more or less sensitive to these influences. Two different methods of nephelometric turbidity measurement were assessed (using instruments confirming to two different turbidity standard methods: EPA 180.1 and ISO 7027). We investigated the influence of particulate organic matter and coloured dissolved organic matter on relationships between turbidity and suspended sediment concentration for rivers in diverse Otago catchments, in the South Island of New Zealand. The presence of organic matter and dissolved colour affected turbidity measurement owing to light absorption; however, turbidity measurement following the ISO 7027 standard, which specifies near infrared radiation at wavelengths where organic absorption is very weak, was less affected by organics. As a result, rating equations between suspended sediment and turbidity may be significantly different with ISO 7027 compared with EPA 180.1 methods.  相似文献   
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