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Chlorination of gloves has gained popularity as a more permanent method of reducing the inherent tackiness of natural rubber latex compared to using powder as a dusting lubricant. Transmission of proteins in natural rubber latex into the air as a result of using powder on natural rubber latex gloves may cause serious complications to allergic individuals. A methodology for characterizing commercial chlorinated natural rubber latex gloves using a combination of attenuated total reflectance (ATR)–Fourier transform infrared (FTIR) spectroscopy and ion chromatography (IC) is described. ATR–FTIR studies established that 930–915 and 670–650 cm−1 are definitive wavenumber ranges for the identification of chlorine in commercial chlorinated latex gloves. Confirmation of the ATR–FTIR results and semiquantification of the chlorine content in the latex gloves was carried out by the IC technique. This methodology can be used by glove manufacturers to determine the amount of chlorine in batches of commercial gloves, and thereby prevent possible threats to public health arising from the deterioration of surgical and examination chlorinated latex gloves under severe storage conditions before the end of their expected shelf life. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 672–682, 2001  相似文献   
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Many studies use the number of fish meals as an estimate of Hg intake, although fish Hg concentrations, even within the same species, can greatly vary. Furthermore, most freshwater advisories only refer to local catch, while market fish advisories only focus on market fish, although both can contribute to Hg body burden. The present study, carried out in lakeside communities from 2 ecosystems in Quebec, Canada, sought to (i) estimate Hg intake from local freshwater sources, hunted waterfowl and market fish and seafood, and (ii) examine the relations between fish consumption, estimated Hg intake and biomarkers of exposure. A total of 238 adults (18-74 years), who had consumed local catch within the past three months, responded to an extensive interview-administered fish and waterfowl frequency questionnaire. Anthropometric measures were taken and a self-administered questionnaire was used to obtain socio-demographic information. Hg intake was estimated as µg Hg/kg body weight/day. Blood and hair samples were analyzed for Hg content. Results showed that persons from one ecosystem ate significantly more fish compared to those from the other (median: 52.1 g/day vs 38.9 g/day), but presented significantly lower concentrations of hair Hg (median: 448.0 ng/g vs 730.5 ng/g), blood organic Hg (median: 1.1 µg/L vs 3.4 µg/L) and inorganic Hg (median: 0.4 µg/L vs 0.8 µg/L). Median daily total Hg intake was 0.080 µg/kg bw/day for the former community and 0.141 µg/kg bw/day for the latter. Overall, 59.5% from the first ecosystem and 41.0% from the other, exceeded the US EPA RfD (0.1 µg/kg bw/day), while 13.2% and 6.0%, respectively, exceeded the Canadian tolerable daily intake (0.47 µg/kg bw/day) for adults. For the two groups, freshwater fish consumption frequency, but not total fish, was positively associated with bioindicators of Hg while estimated Hg intake from freshwater catch as well as from total fish consumption were positively related to Hg biomarkers. There was a positive relation between consumption and estimated Hg intake from freshwater fish and blood inorganic Hg. These findings indicate that the number of fish can be a poor surrogate for Hg exposure. The differences observed here for Hg intake and exposure reflect ecosystem disparities in fish diversity and Hg bioaccumulation. Studies and advisories need to consider Hg fish concentrations and fish-eating patterns in different ecosystems, as well as the contribution of market fish. The relation between fish consumption and inorganic Hg exposure, reported as well in other studies, needs to be further investigated.  相似文献   
34.
Up to 37% of individuals experience chronic pain during their lifetimes. Approximately one fourth of primary care patients with chronic pain also meet criteria for major depression. Many of these individuals fail to receive psychotherapy or other treatment for their depression; moreover, when they do, physical pain is often not addressed directly. Women, socioeconomically disadvantaged individuals, African Americans, and Latinos all report higher rates of pain and depression compared with other groups. This article describes a version of interpersonal psychotherapy tailored for patients with comorbid depression and chronic pain, interpersonal psychotherapy for depression and pain (IPT-P). IPT-P potentially could be delivered to many patient populations in a range of clinical settings, but this article focuses on its delivery within primary care settings for socioeconomically disadvantaged women. Adaptations include a brief 8-session protocol that incorporates strategies for anticipating barriers to psychotherapy, accepting patients' conceptualization of their difficulties, encouraging patients to consider the impact of their pain on their roles and relationships, emphasizing self-care, incorporating pain management techniques, and flexible scheduling. In addition, IPT-P is designed as an adjunct to usual medical pain treatment, and seeks to engage non–treatment-seeking patients in psychotherapy by focusing on accessibility and relevance of the intervention to concerns common among patients with pain. Identifying patients with comorbid depression and chronic pain and offering IPT-P as a treatment option have the potential to improve clinical outcomes for individuals with depression and chronic pain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Lipid droplets (LDs) have traditionally been thought of as solely lipid storage compartments for cells; however, in the last decade, they have emerged as critical organelles in health and disease. LDs are highly dynamic within cells, and their movement is critical in organelle–organelle interactions. Their dynamics are known to change during cellular stress or nutrient deprivation; however, their movement during pathogen infections, especially at very early timepoints, is under-researched. This study aimed to track LD dynamics in vitro, in an astrocytic model of infection. Cells were either stimulated with a dsRNA viral mimic, poly I:C, or infected with the RNA virus, Zika virus. Individual LDs within infected cells were analysed to determine displacement and speed, and average LD characteristics for multiple individual cells calculated. Both LD displacement and mean speed were significantly enhanced in stimulated cells over a time course of infection with an increase seen as early as 2 h post-infection. With the emerging role for LDs during innate host responses, understanding their dynamics is critical to elucidate how these organelles influence the outcome of viral infection.  相似文献   
38.
This study focuses on understanding the relationship between iron redox, composition, and heat-treatment atmosphere in nepheline-based model high-level nuclear waste glasses. Glasses in the Na2O–Al2O3–B2O3–Fe2O3–SiO2 system with varying Al2O3/Fe2O3 and Na2O/Fe2O3 ratios have been synthesized by melt-quench technique and studied for their crystallization behavior in different heating atmospheres—air, inert (N2), and reducing (96%N2–4%H2). The compositional dependence of iron redox chemistry in glasses and the impact of heating environment and crystallization on iron coordination in glass-ceramics have been investigated by Mössbauer spectroscopy and vibrating sample magnetometry. While iron coordination in glasses and glass-ceramics changed as a function of glass chemistry, the heating atmosphere during crystallization exhibited minimal effect on iron redox. The change in heating atmosphere did not affect the phase assemblage but did affect the microstructural evolution. While glass-ceramics produced as a result of heat treatment in air and N2 atmospheres developed a golden/brown colored iron-rich layer on their surface, those produced in a reducing atmosphere did not exhibit any such phenomenon. Furthermore, while this iron-rich layer was observed in glass-ceramics with varying Al2O3/Fe2O3 ratio, it was absent from glass-ceramics with varying Na2O/Fe2O3 ratio. An explanation of these results has been provided on the basis of kinetics of diffusion of oxygen and network modifiers in the glasses under different thermodynamic conditions. The plausible implications of the formation of iron-rich layer on the surface of glass-ceramics on the chemical durability of high-level nuclear waste glasses have been discussed.  相似文献   
39.
Two samples, consisting of a total of 1,027 6th–12th graders from separate communities, were given measures of peer conformity dispositions (willingness to accede to peer pressure), perceptions of peer pressure, and self-reported frequency of behavior concerning 2 major aspects of teenage life: peer involvement (degree of socializing with friends) and misconduct (drug/alcohol use, sexual intercourse, and minor delinquent behavior). Results indicate that Ss perceived less peer pressure toward misconduct than peer involvement and also were comparatively less willing to follow peers in misconduct. Nevertheless, perceived peer pressure and conformity disposition accounted for more of the variance in self-reported misconduct than in self-reported peer involvement. Age differences were modest and varied among measures and samples. The samples also differed in the magnitude of perceived pressures and conformity dispositions as well as in the degree to which these variables were associated with self-reported behavior. It is concluded that the findings reveal a complexity in adolescent conformity that bears elaboration in future research. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
40.
This study evaluated the effectiveness of two posttreatment programs designed to enhance the maintenance of weight loss. Eighty-five obese clients were randomly assigned to either (a) behavior therapy plus a peer-support maintenance program, (b) behavior therapy plus a therapist-contact maintenance program, or (c) behavior therapy only. At a 7-month follow-up session, the therapist-contact program resulted in significantly greater maintenance of weight loss compared with the peer support and behavior therapy only conditions. However, by the time of an 18-month follow-up assessment, overall relapse rates were equivalent across conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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