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It is increasingly acknowledged that homelessness involves more than just being without a house. Indeed, more recent definitions of what constitutes a home highlight the role of social connections and support (including, for example, access to space to engage in social relations). This study examined the role of secure housing and social support as predictors of psychological well-being of individuals following a period of homelessness. Using linear mixed models for longitudinal data, we investigated how changes in social support predicted changes in individuals’ self-reported personal well-being, life satisfaction and mood following a period of homelessness (n = 119), controlling for housing status, alcohol use and employment status. The results showed that remaining homeless predicted poorer personal well-being, life satisfaction and mood. In addition, changes in social support predicted well-being over and above housing stability. Implications of findings for policy and practice in the homeless sector are discussed.  相似文献   
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Immobilized Rhizopus arrhizus biomass was studied in a continuous sorption and desorption mode in order to identify factors that affect the long term uranium biosorptive uptake capacity performance of the immobilized biomass. Laboratory-scale continuous operation pilot plant experiments were performed using synthetic uranyl nitrate and industrial uranium mine leachate solutions. Analysis of the liquid solutions indicated that the immobilized Rhizopus arrhizus biomass successfully recovered all of the uranium from the dilute (less than 500 mg U dm−3) solutions. All uranium can subsequently be eluted, yielding highly concentrated uranium eluates. The immobilized Rhizopus arrhizus biomass maintained its uranium biosorptive uptake capacity over 12 successive sorption–elution cycles when synthetic uranyl nitrate solutions were used. However, when used with mine leachate solutions, an 18% reduction in the uranium biosorptive uptake capacity occurred within the first four adsorption–elution cycles. Spectral analysis indicated that, during continuous use and reuse, the immobilized biomass retained its structural integrity. EDAX, scanning and transmission electron microscopic techniques employed on the microbial biomass suggested that the presence of aluminium interferes with the uranium biosorption process. Spectral analysis also indicated that the presence of silicon enhances the negative effect of the presence of aluminium on the uranium biosorptive uptake capacity of the immobilized Rhizopus arrhizus biomass particles. © 1997 SCI  相似文献   
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Since the approval of the first monoclonal antibody (mAb) in 1986, a huge effort has been made to guarantee safety and efficacy of therapeutic mAbs. As of July 2021, 118 mAbs are approved for the European market for a broad range of clinical indications. In order to ensure clinical efficacy and safety aspects, (pre-)clinical experimental approaches evaluate the respective modes of action (MoA). In addition to antigen-specificity including binding affinity and -avidity, MoA comprise Fc-mediated effector functions such as antibody dependent cellular cytotoxicity (ADCC) and the closely related antibody dependent cellular phagocytosis (ADCP). For this reason, a variety of cell-based assays have been established investigating effector functions of therapeutic mAbs with different effector/target-cell combinations and several readouts including Fcγ receptor (FcγR)-mediated lysis, fluorescence, or luminescence. Optimized FcγR-mediated effector functions regarding clinical safety and efficacy are addressed with modification strategies such as point mutations, altered glycosylation patterns, combination of different Fc subclasses (cross isotypes), and Fc-truncation of the mAb. These strategies opened the field for a next generation of therapeutic mAbs. In conclusion, it is of major importance to consider FcγR-mediated effector functions for the efficacy of therapeutic mAbs.  相似文献   
25.
CK-666 (1) is a recently discovered small-molecule inhibitor of the actin-related protein 2/3 (Arp2/3) complex, a key actin cytoskeleton regulator with roles in bacterial pathogenesis and cancer cell motility. Although 1 is commercially available, the crystal structure of Arp2/3 complex with 1 bound has not been reported, making its mechanism of action uncertain. Furthermore, its relatively low potency increases its potential for off-target effects in vivo, complicating interpretation of its influence in cell biological studies and precluding its clinical use. Herein we report the crystal structure of 1 bound to Arp2/3 complex, which reveals that 1 binds between the Arp2 and Arp3 subunits to stabilize the inactive conformation of the complex. Based on the crystal structure, we used computational docking and free-energy perturbation calculations of monosubstituted derivatives of 1 to guide optimization efforts. Biochemical assays of ten newly synthesized compounds led to the identification of compound 2, which exhibits a threefold increase in inhibitory activity in vitro relative to 1. In addition, our computational analyses unveiled a surface groove at the interface of the Arp2 and Arp3 subunits that can be exploited for additional structure-based optimization.  相似文献   
26.
Abstract

SrBi2Ta2O9 (SBT) is an attractive material for nonvolatile ferroelectric memory applications. In this paper we report on the deposition of highly epitaxial and smooth SrBi2Ta2O9 films on (110) SrTiO3substrates. The films were grown by pulsed laser deposition at temperatures ranging from 600 to 800°C and at various laser fluences from a Bi-excess SBT target. The background oxygen pressure was maintained at 28 Pa during the film deposition. Structural characterization of the films was performed by x-ray diffraction. Atomic force microscopy was used to investigate morphology and growth of the films. The films grew with preferred (115) or (116) orientation. The roughness was of the order of unit cell height. The films display a growth pattern resulting in corrugated film morphology.  相似文献   
27.
A selectionist theory states that violence by males toward male peers originally served specific functions and violence to female peers served others. Differences in self-reported victimization and perpetration in studies of 1,452 high school students were hypothesized. In Study 1, male-to-male aggression was reported to be more prevalent than male-to-female aggression. For male-to-male aggression, perpetrator reports agreed with or exceeded victim reports, and victims were more often strangers than close friends. In contrast, for male-to-female aggression, there were consistently fewer reports from perpetrators than from victims, and victims were less often strangers than girlfriends. Study 2 obtained similar findings for reported frequency, number of victims and perpetrators, and sexual aggression. Study 3 showed that girls' aggression contrasted with that by boys with respect to intra- versus intersex aggression and perpetrator–victim agreement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Foodborne illness caused by Salmonella spp. is a worldwide problem. In the United States Salmonella Enteritidis is the second most commonly isolated serotype from human illness, and is known to be strongly associated with shell eggs and egg containing products. Eggs can become contaminated internally either by penetration through the shell or directly during formation in the reproductive tract. This review begins with a brief account of the physiology of egg production and the various physical and chemical barriers the egg possesses to prevent bacterial contamination. Factors involved in vertical and horizontal transmission of S. Enteritidis are examined, as well as the role of forced molt in colonization of the hen. Pre- and post-harvest mitigation strategies are also discussed.  相似文献   
30.
Federal and state wildlife managers have endeavored to reduce populations of cormorants on Lake Champlain since 1999. These efforts have relied on the presumption of a nuisance species attitude toward cormorants shared among the public. We employed the concept of attitude strength to explore beliefs, sentiments, and intentions that different recreational groups hold toward cormorants, and to gauge the social acceptability of population control on Lake Champlain. Results confirmed that people generally agreed with the nuisance species label. Overall attitudes toward cormorants leaned toward the negative side, and respondents tended to support hazing of nesting birds, egg oiling, and even state-sponsored shooting as population control measures. Strongest objections to cormorants came from anglers and lakeshore homeowners, whereas boaters and conservation group members were more ambivalent about cormorants and population control measures. Moreover, when analyzing attitude strength dimensions, results showed that overall ambivalence about cormorants was prevalent, negative attitudes may be based in cultural differences and social class, and those with the strongest negative attitudes may be fitting knowledge to attitudes.  相似文献   
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