223 research outputs found
Integration of quality, environment and safety management systems in a foundry
The management systems in the Foundry in question were integrated by means of a quality management system according to ISO 9001 standard. This means that the quality management system is a basic management structure in the enterprise, into which elements of environment management and work safety management have been incorporated. In pre4sented paper we describe some problems of management system integration in metallurgical industry
Examining the Associations Between Financial Conditions and Study Abroad in Diverse, Low-income College Students
The study examines ascribed, financial, and college factors to predict study abroad participation among a national sample of students from financially disadvantaged backgrounds. Based on a longitudinal sample of 398 fourth-year participants of a national scholarship program (consisting of more than 50% students of color and 50% first-generation college goers), results show that despite higher study abroad participation among this group compared to national averages, finances remain a predominant impediment. The results provide a counter-narrative that study abroad participation is for the privileged. Findings also indicate that grant aid and prior exposure to financial adversity in the form of severe poverty are associated with an increased likelihood of study abroad participation, and that these relationships tend not to be moderated by gender or ethnoracial identity. Exploratory information on student motivations for study abroad is also reported. Given the importance of study abroad to learning outcomes, this study points to the importance of attracting to study abroad those for whom the college experience marks a significant break from the adverse conditions of their youth and may inform how study abroad, academic, and financial aid advisors can work with students to find funding sources to make an international experience a reality
CD98hc facilitates B cell proliferation and adaptive humoral immunity.
The proliferation of antigen-specific lymphocytes and resulting clonal expansion are essential for adaptive immunity. We report here that B cell-specific deletion of the heavy chain of CD98 (CD98hc) resulted in lower antibody responses due to total suppression of B cell proliferation and subsequent plasma cell formation. Deletion of CD98hc did not impair early B cell activation but did inhibit later activation of the mitogen-activated protein kinase Erk1/2 and downregulation of the cell cycle inhibitor p27. Reconstitution of CD98hc-deficient B cells with CD98hc mutants showed that the integrin-binding domain of CD98hc was required for B cell proliferation but that the amino acid-transport function of CD98hc was dispensable for this. Thus, CD98hc supports integrin-dependent rapid proliferation of B cells. We propose that the advantage of adaptive immunity favored the appearance of CD98hc in vertebrates
Masked mRNA is stored with aggregated nuclear speckles and its asymmetric redistribution requires a homolog of mago nashi
<p>Abstract</p> <p>Background</p> <p>Many rapidly developing systems rely on the regulated translation of stored transcripts for the formation of new proteins essential for morphogenesis. The microspores of the water fern <it>Marsilea vestita </it>dehydrate as they mature. During this process both mRNA and proteins required for subsequent development are stored within the microspores as they become fully desiccated and enter into senescence. At this point microspores become transcriptionally silent and remain so upon rehydration and for the remainder of spermatogenesis. Transcriptional silencing coupled with the translation of preformed RNA makes the microspore of <it>M. vestita </it>a useful system in which to study post-transcriptional regulation of RNA.</p> <p>Results</p> <p>We have characterized the distribution of mRNA as well as several conserved markers of subnuclear bodies within the nuclei of desiccating spores. During this period, nuclear speckles containing RNA were seen to aggregate forming a single large coalescence. We found that aggregated speckles contain several masked mRNA species known to be essential for spermatogenesis. During spermatogenesis masked mRNA and associated speckle proteins were shown to fragment and asymmetrically localize to spermatogenous but not sterile cells. This asymmetric localization was disrupted by RNAi knockdown of the <it>Marsilea </it>homolog of the Exon Junction Complex core component Mago nashi.</p> <p>Conclusions</p> <p>A subset of masked mRNA is stored in association with nuclear speckles during the dormant phase of microspore development in <it>M. vestita</it>. The asymmetric distribution of specific mRNAs to spermatogenous but not sterile cells mirrors their translational activities and appears to require the EJC or EJC components. This suggests a novel role for nuclear speckles in the post-transcriptional regulation of transcripts.</p
B cell repertoires in HLA-sensitized kidney transplant candidates undergoing desensitization therapy
The worldwide trend to high participation higher education: dynamics of social stratification in inclusive systems
Worldwide participation in higher education now includes one-third of the age cohort and is growing at an unprecedented rate. The tendency to rapid growth, leading towards high participation systems (HPS), has spread to most middle-income and some low-income countries. Though expansion of higher education requires threshold development of the state and the middle class, it is primarily powered not by economic growth but by the ambitions of families to advance or maintain social position. However, expansion is mostly not accompanied by more equal social access to elite institutions. The quality of mass higher education is often problematic. Societies vary in the extent of upward social mobility from low-socio-economic-status backgrounds. The paper explores the intersection between stratified social backgrounds and the stratifying structures in HPS. These differentiating structures include public/private distinctions in schooling and higher education, different fields of study, binary systems and tiered hierarchies of institutions, the vertical ‘stretching’ of stratification in competitive HPS, and the unequalising effects of tuition. Larger social inequalities set limits on what education can achieve. Countries with high mobility sustain a consensus about social equality, and value rigorous and autonomous systems of learning, assessment and selection in education
- …