1,471 research outputs found

    Assessing Solvent Exposure In Connecticut Auto Body Shops

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    Objective The objectives of this paper are to characterize solvent exposure on an individual basis by auto body shop tasks, establish if solvent concentrations fall below current regulatory standards, and to determine predictive factors for solvent exposure levels. Predictive factors being analyzed are: indoor temperature, outdoor temperature, indoor relative humidity, outdoor relative humidity, booth type, ventilation (bay door use and general exhaust use), paint type, and specific task. Methods Data for this paper was obtained from The SPRAY (Survey of Painters and Repairers of Autobodies by Yale) study. All statistical analysis was performed in SAS. A log transformation was first applied on all the solvent concentrations to normalize the substantial skew in the distribution. Descriptive statistics were calculated. Regression models were created for each solvent and total solvent concentration. A bivariate model was first created for each solvent and predictor. Then stepwise regression (backwards elimination) was employed to create parsimonious models. Results The solvents with the greatest maximum concentrations are acetone, toluene, and m&p xylene. Benzene had the lowest average (0.07 mg/m3) concentration and range (0-3.13 mg/m3). All of the samples fell below current regulatory limits with the exception of one toluene sample. With the exception of m&p xylene, task was a significant predictor variable for all solvents and total solvent concentrations. The tasks that produced the highest levels of solvent concentrations are: gun cleaning, spraying, and mixing. Conclusion Most solvent concentrations in the SPRAY study fall well below regulatory standards. However, this is not an indicator of safety as many regulatory standards are outdated. Future studies should explore the health effects of chronic exposure to permissible levels of solvents

    Laminin and Heparan Sulfate Proteoglycan Mediate Epithelial Cell Polarization in Organotypic Cultures of Embryonic Lung Cells: Evidence Implicating Involvement of the Inner Globular Region of Laminin β 1 Chain and the Heparan Sulfate Groups of Heparan Sulfate Proteoglycan

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    AbstractThe extracellular matrix and in particular the basement membrane (BM) play an important role in the induction of organotypic rearrangement of cells in culture. This process involves cell aggregation, sorting into epithelial and mesenchymal components, epithelial cell polarization, and lumen formation. In this study, a combination of laminin (LM) and heparan sulfate proteoglycan (HSPG), two major BM constituents, induced organotypic rearrangement of embryonic mouse lung cells. In the absence of LM/HSPG supplementation, the cells sorted into epithelial and mesenchymal compartments but epithelial cell polarization and lumen formation did not occur. Neither LM nor HSPG alone could trigger this process. Synthetic peptide F-9, representing an amino acid sequence from the inner globular region of the laminin β1 chain (RYVVLPRPVCFEKGMNYTVR) induced organotypic cell rearrangement when substituted for LM. Exogenous LM as well as peptide F-9 were localized at the epithelial–mesenchymal interface of organotypic cultures, where a BM-like structure is formedde novo.Organotypic cell rearrangement was blocked by heparin, heparan sulfate, or antibodies against peptide F-9. Binding assays indicated that peptide F-9 interacts with HSPG but not with LM or type IV collagen. Preincubation of embryonic lung cells with peptide F-9 resulted in a significant increase in cell attachment to HSPG but not to other major BM constituents. These findings suggest that the interaction between LM and BM HSPG is critical for the development of epithelial cell polarization and lumen formation. This interaction occurs at the epithelial–mesenchymal interface and is mediated by a site in the LM molecule represented by peptide F-9 and the heparan sulfate groups of HSPG

    Development of a web-enabled learning platform for geospatial laboratories: improving the undergraduate learning experience

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    This paper describes a web-enabled learning platform providing remote access to geospatial software that extends the learning experience outside of the laboratory setting. The platform was piloted in two undergraduate courses, and includes a software server, a data server, and remote student users. The platform was designed to improve the quality of the learning experience and to increase student confidence and proficiency with software-based geospatial skills. Laboratory grades of students using the platform were significantly higher than those of students who did not use the platform, and survey responses reported that students overwhelmingly liked the convenience of the platform, which allowed them to work from any location

    A Model for Selecting Technologies in New Product Development

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    Due to fast changing technologies, shortening product lifecycles, and increased global competition, companies today often need to develop new products continuously and faster. Successful introduction and acceleration of new product development (NPD) is important to obtain competitive advantage for companies. Since technology selection for NPD involves complex decision makings that are critical to the profitability and growth of a company, the selection of the most appropriate technology for a new product requires the use of a robust decision-making framework capable of evaluating several technology candidates based on multiple criteria. This paper presents an integrated model that adopts interpretive structural modeling (ISM) and fuzzy analytic network process (FANP) to evaluate various different available technologies for NPD. The ISM is used to understand the interrelationships among the factors, and the FANP is to facilitate the evaluation process of decision makers under an uncertain environment with interrelated factors. A case study of a flat panel manufacturer is performed to examine the practicality of the proposed model. The results show that the model can be applied for group decision making on the available technology evaluation and selection in new product development

    Crystal structure of human nuclear pore complex component NUP43

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    AbstractNuclear pore complexes (NPC) form nuclear pores that cross the nuclear envelope and allow molecules to transport between the nucleus and the cytoplasm. We solved the crystal structure of human Nup43 (hNUP43), an important component in the Nup107 subcomplex of NPC. hNup43 adopts a seven-bladed β-propeller fold. We confirmed by ITC that neither human Nup37 (hNup37) nor human Nup133 (hNup133) interacts with hNup43. We demonstrated by analytical gel filtration that the human Nup85-Seh1L binary complex recruits hNup43 to form a ternary complex. Based on amino acid sequence analysis, we predicted the hNup85-hSeh1L binding surface of hNup43
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