887 resultados para Reject of emerald mining. Environment. Sustainability. Isolating transformed refractory materials
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The focus of this article is on the role of family in adolescent outcomes when sexual abuse has occurred. The authors identify environmental factors for promoting well-being among adolescents. Two hypotheses aim to examine the systemic influence on adolescents who have been sexually abused, with regard to: 1) mesosystemic barriers (i.e., low levels of school engagement and peer relationships), and 2) exosystemic risk factors (i.e., low levels of social support, socioeconomic status, and community safety, as well as large community size).
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The purpose of this project was to determine if stability of specific antibody secretion improved after fusion of Epstein-Barr virus (EBV)-transformed lymphoblastoid cells with P3X63Ag8.653 murine myeloma cells. Production of human monoclonal antibodies by Epstein-Barr virus transformation and somatic cell fusion has been used by many laboratories, however the steps involved have not been fully optimized. B lymphocytes isolated from the peripheral blood of normal donors were enriched for Thomsen-Friedenreich (T) antigen-reactive cells by panning on asialoglycophorin. The EBV-transformed lymphoblastoid cell lines generated from asialoglycophorin-adherent B lymphocytes were treated in three different manners: (1) cloned and maintained in culture as monoclonal lymphoblastoid cell lines, (2) cloned and fused with murine myeloma cells or (3) fused shortly after transfomation without prior cloning. Cloned lymphoblastoid cell lines maintained in culture without fusion either died or lost specific antibody secretion within five months. Uncloned lymphoblastoid cells remained viable for up to three months but lost specific antibody secretion within two months probably due to overgrowth by nonspecific clones. In an attempt to increase longevity and to stabilize specific antibody secretion by these cells, the cloned lymphoblastoid cells were fused with murine myeloma cells. In nine of ten fusions no hybrids were recovered. As an alternate approach, uncloned lymphoblastoid cells secreting T antigen-specific antibody were hybridized with murine myeloma cells, hybrids secreting T antigen-specific antibody were recovered in six of seven fusions. Furthermore, T antigen-specific antibodies of high titer were secreted by the heterohybridoma clones for more than five months of continuous culture. These heterohybridoma cells secreted more immunoglobulin, produced greater titers of antibody and maintained specific antibody secretion longer than either monoclonal or polyclonal EBV-transformed lymphoblastoid cells. These studies have conclusively demonstrated that fusion of polyclonal lymphoblastoid cells secreting T antigen-specific antibody with murine myeloma cells results in prolongation of human monoclonal antibody production compared with unfused monoclonal or polyclonal lymphoblastoid cell lines. This procedure should be generally applicable for the production of stable human monoclonal antibody-secreting cells lines from peripheral blood lymphocytes. ^
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by Maurice Fishberg
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The MUC1 gene encodes a transmembrane mucin glycoprotein that is overexpressed in several cancers of epithelial origin, including those of breast, pancreas, lung, ovary, and colon. Functions of MUC1 include protection of mucosal epithelium, modulation of cellular adhesion, and signal transduction. Aberrantly increased expression of MUC1 in cancer cells promotes tumor progression through adaptation of these functions. Some regulatory elements participating in MUC1 transcription have been described, but the mechanisms responsible for overexpression are largely unknown. A region of MUC1 5′ flanking sequence containing two conserved potential cytokine response elements, an NFκB site at −589/−580 and a STAT binding element (SBE) at −503/−495, has been implicated in high level expression in breast and pancreatic cancer cell lines. Persistent stimulation by proinflammatory cytokines may contribute to increased MUC1 transcription by tumor cells. ^ T47D breast cancer cells and normal human mammary epithelial cells (HMEC) were used to determine the roles of the κB site and SBE in basal and stimulated expression of MUC1. Treatment of T47D cells and HMEC with interferon-γ (IFNγ) alone enhanced MUC1 expression at the level of transcription, and the effect of IFNγ was further stimulated by tumor necrosis factor-α (TNFα). MUC1 responsiveness to these cytokines was modest in T47D cells but clearly evident in HMEC. Transient transfection of T47D cells with mutant MUC1 promoter constructs revealed that the κB site at −589/−580 and the SBE at −503/−495 and were required for cooperative stimulation by TNFα and IFNγ. Electrophoretic mobility shift assays (EMSA) revealed that the synergy was mediated not by cooperative binding of transcription factors but by the independent actions of STAT1α and NFκB p65 on their respective binding sites. Independent mutations in the κB site and SBE abrogated cytokine responsiveness and reduced basal MUC1 promoter activity by 45–50%. However, only the κB site appeared to be constitutively activated in T47D cells, in part by NFκB p65. These findings implicate two cytokine response elements in the 5 ′ flanking region of MUC1, specifically a κB site and a STAT binding element, in overexpression of MUC1 in breast cancer cells. ^
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Triglyceride levels are a component of plasma lipids that are thought to be an important risk factor for coronary heart disease and are influenced by genetic and environmental factors, such as single nucleotide polymorphisms (SNPs), alcohol intake, and smoking. This study used longitudinal data from the Bogalusa Heart Study, a biracial community-based survey of cardiovascular disease risk factors. A sample of 1191 individuals, 4 to 38 years of age, was measured multiple times from 1973 to 2000. The study sample consisted of 730 white and 461 African American participants. Individual growth models were developed in order to assess gene-environment interactions affecting plasma triglycerides over time. After testing for inclusion of significant covariates and interactions, final models, each accounting for the effects of a different SNP, were assessed for fit and normality. After adjustment for all other covariates and interactions, LIPC -514C/T was found to interact with age3, age2, and age and a non-significant interaction of CETP -971G/A genotype with smoking status was found (p = 0.0812). Ever-smokers had higher triglyceride levels than never smokers, but persons heterozygous at this locus, about half of both races, had higher triglyceride levels after smoking cessation compared to current smokers. Since tobacco products increase free fatty acids circulating in the bloodstream, smoking cessation programs have the potential to ultimately reduce triglyceride levels for many persons. However, due to the effect of smoking cessation on the triglyceride levels of CETP -971G/A heterozygotes, the need for smoking prevention programs is also demonstrated. Both smoking cessation and prevention programs would have a great public health impact on minimizing triglyceride levels and ultimately reducing heart disease. ^
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The role of physical activity in the promotion of individual and population health has been well documented in research and policy publications. Significant research activities have produced compelling evidence for the support of the positive association between physical activity and improved health. Despite the knowledge about these public health benefits of physical activity, over half of US adults do not engage in physical activity at levels consistent with public health recommendations. Just as physical inactivity is of significant public health concern in the US, the prevalence of obesity (and its attendant co-morbidities) is also increasing among US adults.^ Research suggests racial and ethnic disparities relevant to physical inactivity and obesity in the US. Various studies have shown more favorable outcomes among non-Hispanic whites when compared to other minority groups as far as physical activity and obesity are concerned. The health disparity issue is especially important because Mexican-Americans who are the fastest growing segment of the US population are disproportionately affected by physical inactivity and obesity by a significant margin (when compared to non-Hispanic whites), so addressing the physical inactivity and obesity issues in this group is of significant public health concern. ^ Although the evidence for health benefits of physical activity is substantial, various research questions remain on the potential motivators for engaging in physical activity. One area of emerging interest is the potential role that the built environment may play in facilitating or inhibiting physical activity.^ In this study, based on an ongoing research project of the Department of Epidemiology at the University of Texas M. D. Anderson Cancer Center, we examined the built environment, measured objectively through the use of geographical information systems (GIS), and its association with physical activity and obesity among a cohort of Mexican- Americans living in Harris County, Texas. The overall study hypothesis was that residing in dense and highly connected neighborhoods with mixed land-use is associated with residents’ increased participation in physical activity and lowered prevalence of obesity. We completed the following specific aims: (1) to generate a land-use profile of the study area and create a “walkability index” measure for each block group within the study area; (2) to compare the level of engagement in physical activity between study participants that reside in high walkability index block groups and those from low walkability block groups; (3) to compare the prevalence of obesity between study participants that reside in high walkability index block groups and those from low walkability block groups. ^ We successfully created the walkability index as a form of objective measure of the built environment for portions of Harris County, Texas. We used a variety of spatial and non-spatial dataset to generate the so called walkability index. We are not aware of previous scholastic work of this kind (construction of walkability index) in the Houston area. Our findings from the assessment of relationships among walkability index, physical activity and obesity suggest the following, that: (1) that attempts to convert people to being walkers through health promotion activities may be much easier in high-walkability neighborhoods, and very hard in low-walkability neighborhoods. Therefore, health promotion activities to get people to be active may require supportive environment, walkable in this case, and may not succeed otherwise; and (2) Overall, among individuals with less education, those in the high walkability index areas may be less obese (extreme) than those in the low walkability area. To the extent that this association can be substantiated, we – public health practitioners, urban designers, and policy experts – we may need to start thinking about ways to “retrofit” existing urban forms to conform to more walkable neighborhoods. Also, in this population especially, there may be the need to focus special attention on those with lower educational attainment.^
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Invited commentary on "Child Welfare Workers’ Perceptions of the Influence of the Organizational Environment on Permanency Decisions for Families".
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The findings of this study suggest that while child welfare workers are consistently distracted by competing priorities from unexpected events, most are committed, and to understand perspectives is more inclusive and may improve retention rates. Notably, while it is recognized that permanency decisions are not made in an intellectual, legal or clinical vacuum and certain traditional aspects of the bureaucratic structure do not impact decision making, this study advances the body of knowledge on child welfare decision making. Examined in this study are child welfare case workers’ perceptions of the extent to which the organizational environment influences the permanency decisions they make to reunify or terminate parental rights of children placed out-of-home. This study includes a sample of 95 child welfare social workers employed in three public child welfare agencies in the Baltimore and Washington, DC metropolitan area. It used a cross-sectional research design, employing a survey instrument to examine bureaucratic distraction, role conflict, and supervisory adequacy as contextual factors in the organizational environment's influence on permanency outcome decisions. Implications are made for child welfare policy, practice, and research.
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Non-suicidal self-injury (NSSI), such as cutting and burning, is a widespread social problem among lesbian, gay, bisexual, transgender, queer, and questioning (LGBTQ) youth. Extant research indicates that this population is more than twice as likely to engage in NSSI than heterosexual and cisgender (non-transgender) youth. Despite the scope of this social problem, it remains relatively unexamined in the literature. Research on other risk behaviors among LGBTQ youth indicates that experiencing homophobia and transphobia in key social contexts such as families, schools, and peer relationships contributes to health disparities among this group. Consequently, the aims of this study were to examine: (1) the relationship between LGBTQ youth's social environments and their NSSI behavior, and (2) whether/how specific aspects of the social environment contribute to an understanding of NSSI among LGBTQ youth. This study was conducted using an exploratory, sequential mixed methods design with two phases. The first phase of the study involved analysis of transcripts from interviews conducted with 44 LGBTQ youth recruited from a community-based organization. In this phase, five qualitative themes were identified: (1) Violence; (2) Misconceptions, Stigma, and Shame; (3) Negotiating LGBTQ Identity; (4) Invisibility and Isolation; and (5) Peer Relationships. Results from the qualitative phase were used to identify key variables and specify statistical models in the second, quantitative, phase of the study, using secondary data from a survey of 252 LGBTQ youth. The qualitative phase revealed how LGBTQ youth, themselves, described the role of the social environment in their NSSI behavior, while the quantitative phase was used to determine whether the qualitative findings could be used to predict engagement in NSSI among a larger sample of LGBTQ youth. The quantitative analyses found that certain social-environmental factors such as experiencing physical abuse at home, feeling unsafe at school, and greater openness about sexual orientation significantly predicted the likelihood of engaging in NSSI among LGBTQ youth. Furthermore, depression partially mediated the relationships between family physical abuse and NSSI and feeling unsafe at school and NSSI. The qualitative and quantitative results were compared in the interpretation phase to explore areas of convergence and incongruence. Overall, this study's findings indicate that social-environmental factors are salient to understanding NSSI among LGBTQ youth. The particular social contexts in which LGBTQ youth live significantly influence their engagement in this risk behavior. These findings can inform the development of culturally relevant NSSI interventions that address the social realities of LGBTQ youth's lives.
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Nowadays, data mining is based on low-level specications of the employed techniques typically bounded to a specic analysis platform. Therefore, data mining lacks a modelling architecture that allows analysts to consider it as a truly software-engineering process. Here, we propose a model-driven approach based on (i) a conceptual modelling framework for data mining, and (ii) a set of model transformations to automatically generate both the data under analysis (via data-warehousing technology) and the analysis models for data mining (tailored to a specic platform). Thus, analysts can concentrate on the analysis problem via conceptual data-mining models instead of low-level programming tasks related to the underlying-platform technical details. These tasks are now entrusted to the model-transformations scaffolding.
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Data mining is one of the most important analysis techniques to automatically extract knowledge from large amount of data. Nowadays, data mining is based on low-level specifications of the employed techniques typically bounded to a specific analysis platform. Therefore, data mining lacks a modelling architecture that allows analysts to consider it as a truly software-engineering process. Bearing in mind this situation, we propose a model-driven approach which is based on (i) a conceptual modelling framework for data mining, and (ii) a set of model transformations to automatically generate both the data under analysis (that is deployed via data-warehousing technology) and the analysis models for data mining (tailored to a specific platform). Thus, analysts can concentrate on understanding the analysis problem via conceptual data-mining models instead of wasting efforts on low-level programming tasks related to the underlying-platform technical details. These time consuming tasks are now entrusted to the model-transformations scaffolding. The feasibility of our approach is shown by means of a hypothetical data-mining scenario where a time series analysis is required.