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In contrast to earlier approaches to the study of multiple roles, our research was concerned with the frequency and conditions under which both positive and negative outcomes occur. Using data from a random sample of 235 married female nurses, we focused on marital and job satisfaction as important criteria of success in managing multiple roles. In the first phase of the research, a cluster analysis identified five different profiles of marital and job satisfaction. Of the two most positive profiles, one was defined by high scores in both areas, the other by high job satisfaction but only moderate marital satisfaction. In two other profiles, women were very dissatisfied with one role and at best moderately satisfied with the other. In the second phase, the profiles were found to be meaningfully associated with measures of psychological symptomatology and overall life satisfaction. The third phase considered how the profiles were linked to measures of social support and social rejection provided by five key network members. The strongest univariate profile discriminator was the level of work rejection from the spouse. A discriminate function analysis revealed that the level of spouse's work rejection was even more powerful when it was compared to the level of work rejection received from the next closest family member (typically the mother). (53 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Regarding the newly discovered hepatitis G virus (HGV), little is known about its relation to the cause and clinical significance of acute and chronic liver disease and hepatocellular carcinoma. Lacking a reliable serum immunoassay, the only method available for detecting the viral RNA in patients consists of the rather costly and time consuming RT-PCR. HGV has a worldwide distribution with up to 5% voluntary and 12.9% commercial blood donors infected, yet it appears to be asymptomatic. Moreover, HGV is frequently found as a coinfection with HCV or, to a lesser extent, HBV with symptoms tending to follow the patterns known for HCV or HBV infection, respectively. Being a blood-borne virus, it is most prevalent among members of high risk groups, such as IVDUs, patients on hemodialysis, recipients of blood and blood products and patients infected with HCV, HBV, or HIV, HGV can be parenterally, vertically, or sexually transmitted and after prolonged exposure, the virus may be eliminated by the patient's immune response. As yet, no unambiguous evidence exists regarding HGV's role in causing acute or chronic liver disease and, apart from a few isolated reports to the contrary, the infections appear rather mild. Therefore, more studies are required before a decision can be made whether to routinely screen blood donors for the presence of HGV RNA. 相似文献
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Irena Brook Guy Mechrez Ran Y. Suckeveriene Roza Tchoudakov Shiran Lupo Moshe Narkis 《Polymer Composites》2014,35(4):788-794
Electrically conductive elastomeric nanocomposites containing carbon nanotubes (CNT) and polyaniline (PANI) are reported in the present investigation. The synthesis procedure included an in situ inverse emulsion polymerization of aniline doped with dodecylbenzene sulfonic acid (DBSA) in the presence of CNT and dissolved styrene‐isoprene‐styrene (SIS) block copolymer. The PANI synthesis step was carried out by applying ultrasonic energy. The dispersions obtained were processed by two methods: a recently developed precipitation‐filtration procedure, and a conventional drop‐cast procedure. The techniques developed resulted in homogeneous exfoliated PANI coated nanotubes within the elastomeric matrix. The presence of CNT/PANI in the SIS elastomeric matrix affects thermal, mechanical, and electrical properties of the nanocomposites. The formation of continuous three‐dimensional CNT/PANI networks prepared via the precipitation‐filtration method enhances the nanocomposite properties. Contrarily, the intermittent three‐dimensional network prepared by conventional drop‐cast method leads to inferior properties. Nanocomposites produced by both techniques are observed by HRSEM. The two processing techniques result in different structures, which affect the physical properties of the materials produced. A relatively low percolation threshold for both methods was determined. The Young's modulus of the SIS/CNT/PANI significantly increased in the presence of CNT. The precipitation‐filtration technique yields an improved nanocomposite product compared to the drop‐cast route. POLYM. COMPOS., 35:788–794, 2014. © 2013 Society of Plastics Engineers 相似文献
55.
Direct steam generation in parabolic trough or linear Fresnel collectors represents one interesting technological option for concentrating solar electricity production. Today's state of the art characterized by the first commercial plants in operation is a result of more than 20 years of intensive research on this topic. This article provides a review on the key results from research that includes physical effects like heat transfer and pressure drop in horizontal boiler tubes, plant layout considerations, and thermal storage options. An overview on test and demonstration facilities as well as on commercial plants is given, leading to an outlook on the next generation of direct steam generation systems. 相似文献
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Juan S. Rocha-Ortiz Jianchang Wu Jonas Wenzel Andreas J. Bornschlegl Jose Dario Perea Salvador Leon Anastasia Barabash Anna-Sophie Wollny Dirk M. Guldi Jiyun Zhang Alberto Insuasty Larry Lüer Alejandro Ortiz Andreas Hirsch Christoph J. Brabec 《Advanced functional materials》2023,33(44):2304262
Dumbbell-shaped systems based on PAHs-BODIPY-triarylamine hybrids TM-(01-04) are designed as novel and highly efficient hole-transporting materials for usage in planar inverted perovskite solar cells. BODIPY is employed as a bridge between the PAH units, and the effects of the conjugated π-system's covalent attachment and size are investigated. Fluorescence quenching, 3D fluorescence heat maps, and theoretical studies support energy transfer within the moieties. The systems are extremely resistant to UVC 254 nm germicidal light sources and present remarkable thermal stability at degradation temperatures exceeding 350 °C. Integrating these systems into perovskite solar cells results in outstanding power conversion efficiency (PCE), with TM-02-based devices exhibiting a PCE of 20.26%. The devices base on TM-01, TM-03, and TM-04 achieve PCE values of 16.98%, 17.58%, and 18.80%, respectively. The long-term stability of these devices is measured for 600 h, with initial efficiency retention between 94% and 86%. The TM-04-based device presents noticeable stability of 94%, better than the reference polymer PTAA with 91%. These findings highlight the exciting potential of dumbbell-shaped systems based on PAHs-BODIPY-triarylamine derivatives for next-generation photovoltaics. 相似文献
58.
O Déas C Dumont M MacFarlane M Rouleau C Hebib F Harper F Hirsch B Charpentier GM Cohen A Senik 《Canadian Metallurgical Quarterly》1998,161(7):3375-3383
We examined the effects of the cell-permeable, broad spectrum peptide caspase inhibitors, benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethyl ketone (Z-VAD.fmk), and BOC-Asp(OMe)-fluoromethyl ketone (BOC-D.fmk), on apoptosis induced by anti-CD2, anti-Fas, and the protein kinase inhibitor staurosporine in activated human peripheral T lymphocytes. We monitored ultrastructural, flow cytometric, and biochemical apoptotic changes, including externalization of phosphatidylserine, cleavage of poly(ADP-ribose) polymerase (PARP) and lamins, activation of caspase-3 and caspase-7, decrease in mitochondrial membrane potential, and DNA fragmentation. Z-VAD.fmk and BOC-D.fmk completely inhibited all the biochemical and ultrastructural changes of apoptosis in anti-Fas-treated cells. In marked contrast, neither Z-VAD.fmk nor BOC-D.fmk inhibited CD2- or staurosporine-mediated cell shrinkage, dilatation of the endoplasmic reticulum (seen in anti-CD2-treated cells), externalization of phosphatidylserine, and loss of mitochondrial membrane potential that accompanied cell death. However, these inhibitors did inhibit the cleavage of PARP and lamins and the formation of hypodiploid cells, and partially inhibited chromatin condensation. These results demonstrate that in activated T cells, anti-CD2 and staurosporine induce a caspase-independent cell death pathway that exhibits prominent cytoplasmic features of apoptosis. However, caspase activation is required for the proteolytic degradation of nuclear substrates such as PARP and lamins together with the DNA fragmentation and extreme chromatin condensation that occur in apoptotic cells. 相似文献
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CD317 (Tetherin,BST-2或HM1.24)于1994年被发现并命名,是终末分化B细胞的特异性表面标志.2008年首次被鉴定为干扰素诱导型宿主抗病毒因子,此后越来越多的科学家加入到该领域的探索中.经过近十年的研究,目前已经阐述了CD317结构、抗病毒及免疫特性等问题,也陆续发现了一些诸如参与肿瘤进展、束缚外泌体释放等新功能,研究热度不减当年.因此,文章对近几年CD317功能的研究进展进行一个系统的总结,以期为病毒感染、肿瘤发病以及治疗等方面的理论进步和技术发展提供新的思路. 相似文献