4,645 research outputs found

    Near-real-time TOMS, telecommunications and meteorological support for the 1987 Airborne Antarctic Ozone Experiment

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    The goal of the 1987 Airborne Antarctic Ozone Experiment was to improve the understanding of the mechanisms involved in the formation of the Antarctic ozone hole. Total ozone data taken by the Nimbus-7 Total Ozone Mapping Spectrometer (TOMS) played a central role in the successful outcome of the experiment. During the experiment, the near-real-time TOMS total ozone observations were supplied within hours of real time to the operations center in Punta Arenas, Chile. The final report summarizes the role which Research and Data Systems (RDS) Corporation played in the support of the experiment. The RDS provided telecommunications to support the science and operations efforts for the Airborne Antarctic Ozone Experiment, and supplied near real-time weather information to ensure flight and crew safety; designed and installed the telecommunications network to link NASA-GSFC, the United Kingdom Meteorological Office (UKMO), Palmer Station, the European Center for Medium-Range Weather Forecasts (ECMWF) to the operation at Punta Arenas; engineered and installed stations and other stand-alone systems to collect data from designated low-orbiting polar satellites and beacons; provided analyses of Nimbus-7 TOMS data and backup data products to Punta Arenas; and provided synoptic meteorological data analysis and reduction

    The activities of hospital nursing unit managers and quality of patient care in South African hospitals: a paradox?

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    PKBackground: Improving the quality of health care is central to the proposed health care reforms in South Africa. Nursing unit managers play a key role in coordinating patient care activities and in ensuring quality care in hospitals. Objective: This paper examines whether the activities of nursing unit managers facilitate the provision of quality patient care in South African hospitals. Methods: During 2011, a cross-sectional, descriptive study was conducted in nine randomly selected hospitals (six public, three private) in two South African provinces. In each hospital, one of each of the medical, surgical, paediatric, and maternity units was selected (n 36). Following informed consent, each unit manager was observed for a period of 2 hours on the survey day and the activities recorded on a minute-by-minute basis. The activities were entered into Microsoft Excel, coded into categories, and analysed according to the time spent on activities in each category. The observation data were complemented by semi-structured interviews with the unit managers who were asked to recall their activities on the day preceding the interview. The interviews were analysed using thematic content analysis. Results: The study found that nursing unit managers spent 25.8% of their time on direct patient care, 16% on hospital administration, 14% on patient administration, 3.6% on education, 13.4% on support and communication, 3.9% on managing stock and equipment, 11.5% on staff management, and 11.8% on miscellaneous activities. There were also numerous interruptions and distractions. The semi-structured interviews revealed concordance between unit managers’ recall of the time spent on patient care, but a marked inflation of their perceived time spent on hospital administration. Conclusion: The creation of an enabling practice environment, supportive executive management, and continuing professional development are needed to enable nursing managers to lead the provision of consistent and high-quality patient care

    Gene doctoring: a method for recombineering in laboratory and pathogenic Escherichia coli strains

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    Background: Homologous recombination mediated by the lambda-Red genes is a common method for making chromosomal modifications in Escherichia coli. Several protocols have been developed that differ in the mechanisms by which DNA, carrying regions homologous to the chromosome, are delivered into the cell. A common technique is to electroporate linear DNA fragments into cells. Alternatively, DNA fragments are generated in vivo by digestion of a donor plasmid with a nuclease that does not cleave the host genome. In both cases the lambda-Red gene products recombine homologous regions carried on the linear DNA fragments with the chromosome. We have successfully used both techniques to generate chromosomal mutations in E. coli K-12 strains. However, we have had limited success with these lambda-Red based recombination techniques in pathogenic E. coli strains, which has led us to develop an enhanced protocol for recombineering in such strains. \ud \ud Results: Our goal was to develop a high-throughput recombineering system, primarily for the coupling of genes to epitope tags, which could also be used for deletion of genes in both pathogenic and K-12 E. coli strains. To that end we have designed a series of donor plasmids for use with the lambda-Red recombination system, which when cleaved in vivo by the I-SceI meganuclease generate a discrete linear DNA fragment, allowing for C-terminal tagging of chromosomal genes with a 6xHis, 3xFLAG, 4xProteinA or GFP tag or for the deletion of chromosomal regions. We have enhanced existing protocols and technologies by inclusion of a cassette conferring kanamycin resistance and, crucially, by including the sacB gene on the donor plasmid, so that all but true recombinants are counter-selected on kanamycin and sucrose containing media, thus eliminating the need for extensive screening. This method has the added advantage of limiting the exposure of cells to the potential damaging effects of the lambda-Red system, which can lead to unwanted secondary alterations to the chromosome. \ud \ud Conclusion: We have developed a counter-selective recombineering technique for epitope tagging or for deleting genes in E. coli. We have demonstrated the versatility of the technique by modifying the chromosome of the enterohaemorrhagic O157:H7 (EHEC), uropathogenic CFT073 (UPEC), enteroaggregative O42 (EAEC) and enterotoxigenic H10407 (ETEC) E. coli strains as well as in K-12 laboratory strains

    Social Cognition in Schizophrenia: An Overview

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    The purpose of this column is to provide an overview of social cognition in schizophrenia. The column begins with a short introduction to social cognition. Then, we describe the application of social cognition to the study of schizophrenia, with an emphasis on key domains (i.e., emotion perception, Theory of Mind, and attributional style). We conclude the column by discussing the relationship of social cognition to neurocognition, negative symptoms, and functioning, with an eye toward strategies for improving social cognition in schizophrenia

    Prevalence of emotional, physical and sexual abuse of women in three South African provinces.

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    INTRODUCTION: There is growing recognition in the ranks of the South African government that violence against women is a serious problem facing us all. Until now data on the epidemiology of violence against women in South Africa have been scanty. This report presents the findings of the first major community-based prevalence study. OBJECTIVES: To describe the prevalence of physical, sexual, financial, and emotional abuse of women. METHODS: A cross-sectional study conducted in the Eastern Cape (EC), Mpumalanga (MP) and the Northern Province (NP). The sample included one randomly selected woman aged 18-49 years living in each of 2,232 households. The sample was drawn using stratified, multistage, random methods, and 1,306 questionnaires were completed, giving a 90.3% response rate after adjusting for households without an eligible woman. RESULTS: The prevalences of ever having been physically abused by a current or ex-partner were 26.8% (EC), 28.4% (MP) and 19.1% (NP). The prevalences of abuse in the last year were 10.9% (EC), 11.9% (MP) and 4.5% (NP). The prevalences of rape were 4.5% (EC), 7.2% (MP) and 4.8% (NP). Considerable emotional and financial abuse was also reported, e.g. the prevalences of a partner having boasted about or brought home girlfriends in the previous year were 5.0% (EC), 10.4% (MP) and 7.0% (NP): The prevalences of physical abuse during a pregnancy were 9.1% (EC), 6.7% (MP) and 4.7% (NP). The proportions of abused women who were injured in the year before the survey were 34.5% (EC), 48.0% (MP) and 60.0% (NP). CONCLUSIONS: This study is the first large-scale, community-based prevalence study to be undertaken in South Africa

    Effects of seawater and deionized water at 0 to 80 deg C on the flexural properties of a glass/epoxy composite

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    The effect on the flexural properties of a glass/epoxy composite of immersion in deionized water or seawater at 0, 25, and 80 C for 451 hr was examined. The percent weight gain at 0 and 25 C was low (0.06 to 0.17 percent) and there was no significant change in the flexural properties for these environmental conditions. At 80 C there was a decrease in the flexural strength of 17 and 20 percent in seawater and deionized water, respectively. This is a comparison to control samples exposed to 80 C heat alone. These decreases were found to be nearly reversible once the samples were dried. Optical microscopy did not reveal cracking of the matrix. The flexural modulus was essentially unaffected by exposure to deionized water and seawater at 80 C

    In Utero Environmental Tobacco Smoke Exposure Alters Gene Expression in Lungs of Adult BALB/c Mice

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    BACKGROUND: In utero environmental tobacco smoke (ETS) exposure exacerbates initial lung responses of adult mice to ovalbumin (OVA), a common allergen in rodent models of allergic asthma. OBJECTIVE: We tested the hypothesis that in utero ETS exposure alters expression of genes (including asthma-related and inflammatory genes) in the lungs of adult mice and that this differential expression is reflected in differential respiratory and immune responses to nontobacco allergens. METHODS: Using Affymetrix Mouse Genome 430 2.0 arrays, we examined gene expression changes in lungs of BALB/c mice exposed to ETS in utero, OVA, or saline aerosol at weeks 7-8, and OVA sensitization and challenge at weeks 11-15. Data sets were filtered by transcript p-value (\u3c or = 0.05), false discovery rate (\u3c or = 0.05), and fold change (\u3e or = 1.5). Differential expression of selected genes was confirmed by polymerase chain reaction (PCR). RESULTS: Genes differentially expressed as a result of in utero ETS exposure are involved in regulation of biological processes (immune response, cell proliferation, apoptosis, cell metabolism) through altered cytoskeleton, adhesion, transcription, and enzyme molecules. A number of genes prominent in lung inflammation were differentially expressed on PCR but did not pass selection criteria for microarray, including arginase (Arg1), chitinases (Chia, Chi3l3, Chi3l4), eotaxins (Ccl11, Ccl24), small proline-rich protein 2a (Sprr2a), and cytokines (Il4, Il6, Il10, Il13, Tnfa) . CONCLUSION: The differential lung gene expression reported here is consistent with previously reported functional changes in lungs of mice exposed in utero to ETS and as adults to the nontobacco allergen OVA
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