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71.
Trauma survivors with posttraumatic stress disorder (PTSD) often experience or report social stigmatization and isolation. Williams (2001) provided an experimental paradigm to assess behavioral effects of social exclusion. This paradigm (face-to-face version) has been applied in a 2 × 2 group × experimental condition design. Participants in the PTSD group (N = 16) and the nontraumatized control group (N = 25) were randomly assigned to an exclusion or inclusion condition. The results showed interaction effects for main psychopathological assessments (depression, anxiety, psychoticism) and expected main effects for the majority of outcome measures (psychopathology, well-being, belonging, and meaningful existence). The research concludes that a general assumption of elevated levels of self-perceived social exclusion in PTSD patients has to be considered in terms of differentiated psychopathological effects of exclusion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
73.
Odilia I Bermudez Claire Toher Gabriela Montenegro-Bethancourt Marieke Vossenaar Paul Mathias Colleen Doak Noel W Solomons 《Nutrition journal》2010,9(1):20
Background
Consumption of healthy diets that contribute with adequate amounts of fat and fatty acids is needed for children. Among Guatemalan children, there is little information about fat intakes. Therefore, the present study sought to assess intakes of dietary fats and examine food sources of those fats in Guatemalan children. 相似文献74.
75.
A commercial crosslinked ionic polymer AV‐17 containing ? N(CH3)3Cl groups was used. The common compounds of Bi(III) and Al(III); Bi(III) and Cr(III); Bi(III) and Fe(III); Bi(III) and FeOOH and of three components—Bi(III), Fe(III), and Cr(III); Bi(III), FeOOH, and Cr(III) were obtained in the AV‐17 polymer phase and investigated using scanning electron microscopy, powder X‐ray diffraction, thermogravimetric analysis, and Fourier‐transform infrared spectroscopy. It was shown that metal‐containing compounds were concentrated on the surface of the polymer granules. The compounds were in the crystalline (BiOCl) or amorphous (jarosites and oxihydroxides) state. The morphology and composition of the metal‐containing ultra dispersed particles were different on the surface and in the volume of the polymer granule. Most of the metal‐containing compounds were in the form of pseudo spherical particles, but compounds containing Bi(III) and FeOOH in the volume of AV‐17 granule, were in the form of clew of nanometer fibers. Thermogravimetric analysis (in an N2 atmosphere) in the range 24–1000°C of the metallic compounds containing polymer was also carried out. The metal‐containing polymer samples were stable up to 120°C. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
76.
Natalia A. Castillo Alejandra de Moreno de LeBlanc Carolina Maldonado Galdeano Gabriela Perdigón 《Food research international (Ottawa, Ont.)》2012,45(2):831-841
Salmonella produces infections of different nature and severity depending of many factors including the Salmonella serovar involved, strain virulence, infective dose, host animal species, age and immune status of the host. The treatments against Salmonella infections rely on supportive and antibiotic therapy to eliminate the pathogen, but the development of resistance by Salmonella to the antimicrobials most commonly used limits its efficacy. Other disadvantages of antibiotic treatments are that they can lead to acute diarrhea (antimicrobials normally induce an imbalance of intestinal bacterial flora) and may produce chronic toxicity. Considering this undesired consequences of antibiotics and because at the present there are no effective oral vaccines which protect against salmonellosis, scientists have been searching for alternative methods to control enteric infections. In the present review, probiotics are proposed as an attractive possibility to attend this concern. Probiotic are live microorganisms, which when administered in adequate amounts confer a health benefit on the host. In vitro and in vivo studies showed the effectiveness of probiotic administration in the prevention or in the treatment against Salmonella infection. There are several mechanisms by which probiotic strains might exert their effects. They include non immune mechanisms (stabilization of the gut mucosal barrier, competition for adhesion, secretion of antimicrobial substances, etc.) and the modulation of the mucosal and systemic immune responses. These mechanisms are species and/or strain specific. There are also evidences that in some cases, a mix of probiotic strains can be more useful than each strain alone against this infection. In addition, the presence of one or more probiotic strains in a fermented product can improve the beneficial properties of the probiotic strains involved. It was also reviewed the security of probiotics administration after Salmonella infection in healthy host and in immunosuppressed or babies hosts. Although, the major part of the researches were performed in animal models through in vivo assays or by in vitro studies using human cell lines, some studies carried out in humans to verify the probiotic effects were also addressed in the present review. Nevertheless, is of critical importance to perform more clinical trials in humans to validate the results obtained with each specific probiotic strain or probiotic product. 相似文献
77.
Gabriela CorsanoAldo R. Vecchietti Jorge M. Montagna 《Computers & Chemical Engineering》2011,35(8):1384-1398
The always increasing energy demand combined with the declining availability of fossil fuels is driving forces for the investigation of renewable energy sources. In this context, bioethanol is considered as one of the most appropriate solutions for short term gasoline substitution. Then, the motivation of this work is to propose a MINLP optimization model for a sustainable design and behavior analysis of sugar/ethanol supply chain (SC). A detailed model for ethanol plant design is embedded in the SC model, and therefore plant and SC designs are simultaneously obtained. Yeast production and residue recycles are taken into account in order to assess the environmental impact. The inclusion of sustainability issues in the model produces both economic and operative changes in SC and plant designs. The simultaneous optimization of these elements allows the evaluation of several compromises among design and process variables. These issues are highlighted throughout the evaluated studied cases. 相似文献
78.
Marcin Górny Edward Tyrała Gabriela Sikora Łukasz Rogal 《Metals and Materials International》2018,24(1):95-100
In the present work, the Mg2Cu precipitates in copper-alloyed austempered ductile iron (ADI) were identified by analyzing techniques such as TEM and SEM with EDS. It was revealed that, in castings made of ADI-containing copper, highly dispersed particles of Mg2Cu are formed, whose size does not exceed <1 μm. The research work was carried out on ductile iron that was austenitized at 900 °C, followed by austempering at 380 °C. The microstructure was investigated using various techniques, including optical microscopy, XRD, SEM, and TEM. In addition to this, the exhibited impact properties of castings with Cu, Ni, and Cu+Ni were also determined. This study casts a new light on the formation of the structure of Cu-alloyed ADI. The highly-dispersive and brittle Mg2Cu particles that are located in the vicinity of the graphite nodules have a negative effect on the impact properties of ADI. It has also been shown that impact strength decreases from levels of 160-180 J (for copper-free ADI) to 90-120 J (for copper-and copper-nickel-alloyed ADI). 相似文献
79.
Inductively coupled plasma-mass spectrometry (ICP-MS) method EPA 200.8 is gradually finding acceptance as an alternative to uranium analysis. A comparison of the ICP-MS with the accepted radiochemical method EPA 908.0 has been carried out based on data from laboratory control standards, national proficiency test samples, and environmental and drinking water samples from the State of Utah. The method detection limit (MDL) for ICP-MS was determined to be 0.017 microg/L or (0.011 pCi/L), and the minimum reporting limit (MRL) was 0.17 microg/L (MDL x 10) or (0.11 pCi/L). The minimum reporting limit for radiochemical 908.0 method is 1 pCi/L. Our spiked matrix recoveries, spiked blank samples, and reference materials deviate only a few percentage from the listed true values. Results demonstrate that the ICP-MS is a superior analytical tool for the determination of uranium in drinking and environmental waters at concentrations required by the United States Environmental Protection Agency. 相似文献
80.
Although a wide array of variables has been found to predict harsh parenting, less is known about the linkages among these variables. It is suggested here that stress reactivity, as reflected in cortisol changes, is an important mediating variable. In a high-risk population, mothers (N = 60) with low perceived power (as measured by the Parent Attribution Test; D. B. Bugental, J. B. Blue, & M. Cruzcosa, 1989), were highly reactive to infants and toddlers with a difficult temperament pattern. In response to such children, they (a) manifested high cortisol reactivity and (b) reported greater use of harsh control practices (e.g., spanking). Cortisol reactivity was found to mediate the observed relationship between the predictor variable (the interaction between maternal "powerlessness" and the child's temperament) and parental harshness. These findings have clinical implications for the ways in which parental empowerment (via early interventions) can serve to reduce stress and thus the negative outcomes at-risk children may experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献