1,006 research outputs found

    Increasing microbiological confirmation and changing epidemiology of meningococcal disease on Merseyside, England

    Get PDF
    ObjectivesTo determine, for the last 5 years in children on Merseyside with clinical meningococcal disease (MCD), the impact on diagnostic yield of newer bacteriologic methods; bacterial antigen detection (AD) and polymerase chain reaction (PCR).MethodsProspective data collection at Royal Liverpool Children's Hospital over two epochs: 1 September 1992 to 30 April 1994 (epoch A, n = 126) and 17 November 1997 to 15 September 1998 (epoch B, n = 85).ResultsEpoch Awas compared with epoch B. Diagnosis was confirmed by detection of meningococci in 78 of 126 (61.9%) versus 64 of 85 (75.3%, P = 0.04), but with a significantly lower rate of positive blood and cerebrospinal fluid culture in the later epoch. The proportion of cases receiving penicillin pretreatment was unchanged at 32%, but the proportion undergoing lumbar puncture decreased significantly. Median ages were higher in epoch B: 1.7 years versus 2.49 years (P = 0.013, Mann-Whitney). There was a significant increase in the proportion of cases due to serogroup C (14/78 (18%) versus 30/64 (46.9%), P = 0.001).ConclusionsCulture detection of meningococci from children with MCD has reduced, as less lumbar punctures are done. However, improved diagnosis by PCR and AD has increased microbiological confirmation overall. Serogroup C disease and the median age of cases continue to rise

    Influence of intensive melt shearing on the microstructure and mechanical properties of an Al-Mg alloy with high added impurity content

    Get PDF
    The official published version can be accessed from the link below - Copyright @ The Minerals, Metals & Materials Society and ASM International 2011We have investigated the influence of melt conditioning by intensive shearing on the mechanical behavior and microstructure of Al-Mg-Mn-Fe-Cu-Si alloy sheet produced from a small book mold ingot with high added impurity content. The melt conditioned ingot has fine grains throughout its cross section, whereas a conventionally cast ingot, without melt shearing, has coarser grains and shows a wider variation of grain size. Both needle-shaped and coarse Chinese script iron bearing intermetallic particles are found in the microstructure at the center of the conventionally processed ingot, but for the melt conditioned ingot, only fine Chinese script intermetallic particles are observed. In addition to the iron bearing intermetallics, Mg2Si particles are also observed. The ingots were rolled to thin sheet and solution heat treated (SHT). During rolling, the iron-based intermetallics and Mg2Si particles are broken and aligned along the rolling direction. Yield strength (YS), ultimate tensile strength (UTS), and elongation of the intensively melt sheared and processed sheet are all improved compared to the conventionally cast and processed sheet. Fractographic analysis of the tensile fracture surfaces shows that the clustered and coarse iron bearing intermetallic particles are responsible for the observed reduction in mechanical properties of the conventionally cast sheet. We have shown that by refining the initial microstructure of the ingot by intensive shear melt conditioning, it is possible to achieve improved mechanical properties at the final sheet gage of an AlMgMn alloy with a high content of impurities.This study is under the Technology Strategy Board funded REALCAR projec

    Translation to practice: a randomised controlled study of an evidenced based booklet targeted at breast care nurses in the United Kingdom

    Get PDF
    BACKGROUND: In the United Kingdom (UK), it was documented that a problem of knowledge transfer existed within the speciality of breast-cancer care, thus depriving patients of receiving optimal care. Despite increasingly robust research evidence indicating recommendation of whole body exercise for people affected by breast cancer, commensurate changes to practice were not noted amongst breast-care nurses (BCNs). AIM: To evaluate the effect of a targeted booklet, Exercise and Breast Cancer: A Booklet for Breast-Care Nurses, on changes in knowledge, reported practice, and attitudes of BCNs in the UK. METHOD: A prospective, experimental approach was used for designing a pre- and post-test randomised controlled study. Comparisons of knowledge, reported practice, and attitudes based on responses to a questionnaire were made at two time-points in two groups of BCNs (control and experimental). The unit of randomisation and analysis was hospital clusters of BCNs. The sample comprised 92 nurses from 62 hospitals. Analysis consisted of descriptive statistics and clustered regression techniques: clustered logistic regression for knowledge items, clustered linear regression for knowledge scores, ologit for attitude and reported practice items, and clustered multiple regression for paired and multiple variable analysis. RESULTS: A statistically significant increase in knowledge and changes in reported practice and attitudes were found. Robust variables affecting knowledge acquisition were: promotion of health, promotion of exercise, and understanding how exercise can reduce cancer-related fatigue. DISCUSSION: The study has shown that evidence-based printed material, such as an information booklet, can be used as an effective research dissemination method when developed for needs, values, and context of a target audience. CONCLUSIONS: This practical approach to research dissemination could be replicated and applied to other groups of nurses.</p

    Search for Global Dipole Enhancements in the HiRes-I Monocular Data above 10^{18.5} eV

    Full text link
    Several proposed source models for Ultra-High Energy Cosmic Rays (UHECRs) consist of dipole distributions oriented towards major astrophysical landmarks such as the galactic center, M87, or Centaurus A. We use a comparison between real data and simulated data to show that the HiRes-I monocular data for energies above 10^{18.5} eV is, in fact, consistent with an isotropic source model. We then explore methods to quantify our sensitivity to dipole source models oriented towards the Galactic Center, M87, and Centaurus A.Comment: 17 pages, 31 figure

    Observation of the Ankle and Evidence for a High-Energy Break in the Cosmic Ray Spectrum

    Full text link
    We have measured the cosmic ray spectrum at energies above 101710^{17} eV using the two air fluorescence detectors of the High Resolution Fly's Eye experiment operating in monocular mode. We describe the detector, PMT and atmospheric calibrations, and the analysis techniques for the two detectors. We fit the spectrum to models describing galactic and extragalactic sources. Our measured spectrum gives an observation of a feature known as the ``ankle'' near 3×10183\times 10^{18} eV, and strong evidence for a suppression near 6×10196\times 10^{19} eV.Comment: 14 pages, 9 figures. To appear in Physics Letters B. Accepted versio

    Quantifying structural racism in cohort studies to advance prospective evidence

    Get PDF
    Calls-to-action in health research have described a need to improve research on race, ethnicity, and structural racism. Well-established cohort studies typically lack access to novel structural and social determinants of health (SSDOH) or precise race and ethnicity categorization, contributing to a loss of rigor to conduct informative analyses and a gap in prospective evidence on the role of structural racism in health outcomes. We propose and implement methods that prospective cohort studies can use to begin to rectify this, using the Women's Health Initiative (WHI) cohort as a case study. To do so, we evaluated the quality, precision, and representativeness of race, ethnicity, and SSDOH data compared with the target US population and operationalized methods to quantify structural determinants in cohort studies. Harmonizing racial and ethnic categorization to the current standards set by the Office of Management and Budget improved measurement precision, aligned with published recommendations, disaggregated groups, decreased missing data, and decreased participants reporting “some other race”. Disaggregation revealed sub-group disparities in SSDOH, including a greater proportion of Black-Latina (35.2%) and AIAN-Latina (33.3%) WHI participants with income below the US median compared with White-Latina (42.5%) participants. We found similarities in the racial and ethnic patterning of SSDOH disparities between WHI and US women but less disparity overall in WHI. Despite higher individual-level advantage in WHI, racial disparities in neighborhood resources were similar to the US, reflecting structural racism. Median neighborhood income was comparable between Black WHI (39,000)andUS(39,000) and US (34,700) women. WHI SSDOH-associated outcomes may be generalizable on the basis of comparing across race and ethnicity but may quantitatively (but not qualitatively) underestimate US effect sizes. This paper takes steps towards data justice by implementing methods to make visible hidden health disparity groups and operationalizing structural-level determinants in prospective cohort studies, a first step to establishing causality in health disparities research

    Light microscopic observations of the ruminal papillae of cattle on diets with divergent forage to cereal ratios

    Get PDF
    High levels of supplementation with cereal increases production rates in cattle but can increase incidence of disease, ranging from mild indigestion to acute ruminal acidosis and death. Therefore, there is motivation to determine biological markers which can be used to identify whether animals have been, or are being fed, sufficient or excessive cereals. This study aimed to describe light microscopic findings from animals being fed diverse dietary cereal proportions and to test the performance of a novel rumen epithelial scoring system. Rumen wall tissue samples were obtained from the abattoir from 195 cattle from 11 Scottish farms and processed for histological examination. Light microscopic examination was used to characterise ruminal epithelial response to dietary challenge. Secondary objectives included describing the distribution of immune-related cells in bovine ruminal epithelium and assessing the use of a modified Elastin Martius Scarlet Blue stain (EMSB) for histological examination of the rumen epithelium. Cells staining positive for cluster of differentiation 3 were distributed mainly in the lower layers of the stratum basale and were found in higher densities in animals offered lower cereal proportion diets. Cells staining positive for major histocompatibility complex class 2 (MHCII) were most common in perivascular locations and in the junction between the lower stratum basale and the propria-submucosa. The density of MHCII positive staining cells was higher in animals on lower cereal diets. The level of supplementation with cereal was also associated with the thickness of the stratum corneum (SCT) and stratum granulosum (SGT), the integrity of the stratum corneum and sloughing of cornified cells. There were no advantages in using EMSB stain over haematoxylin and eosin (H and E) in this scoring system. We concluded that a scoring system that included only SCT, SGT and a measure of the loss of appearance of intercellular space allowed differentiation of groups of animals according to the level of cereal supplementation

    Interferon lambda 4 impacts the genetic diversity of hepatitis C virus

    Get PDF
    Hepatitis C virus (HCV) is a highly variable pathogen that frequently establishes chronic infection. This genetic variability is affected by the adaptive immune response but the contribution of other host factors is unclear. Here, we examined the role played by interferon lambda-4 (IFN-λ4) on HCV diversity; IFN-λ4 plays a crucial role in spontaneous clearance or establishment of chronicity following acute infection. We performed viral genome-wide association studies using human and viral data from 485 patients of white ancestry infected with HCV genotype 3a. We demonstrate that combinations of host genetic variants, which determine IFN-λ4 protein production and activity, influence amino acid variation across the viral polyprotein - not restricted to specific viral proteins or HLA restricted epitopes - and modulate viral load. We also observed an association with viral di-nucleotide proportions. These results support a direct role for IFN-λ4 in exerting selective pressure across the viral genome, possibly by a novel mechanism

    Avaliação das práticas diferenciais de amamentação: a questão da etnia

    Get PDF
    Breastfeeding practices in two Brazilian metropolitan areas (S. Paulo and Recife) are described, as part of a study carried out in 1987. In a random sample of healthy 0-8 month old infants, selected from all health care units, higher breastfeeding rates were found in S. Paulo (initiation, prevalence, median and average) than in Recife. The mean duration of breastfeeding, mixed and full, was of 127.5 and 66.6 days, respectively, for S. Paulo, and of 104.4 and 31.7 days for Recife. When data are analysed according to ethnic group, white S. Paulo women breastfeed more than white Recife women. Full breastfeeding rate is more prevalent among white and "mulato" S. Paulo women. However, when the data were analyzed for each city separately, it was found, remarkably, that the non-whites breastfeed more than the whites. In Recife, full breastfeeding is particularly low in whites (of 15.3 days median) and "mulatos" (of 16.7 days), but of 34.5 days in blacks. The study points out the need for greater in-depth investigation of the issue of ethnicity and infant feeding practices, still inadequately understood in world literature.Descreve-se a situação da prática de amamentar em duas áreas metropolitanas brasileiras: São Paulo e Recife, Brasil, em estudos conduzidos em 1987. Em amostras representativas da população de crianças saudáveis de 0-8 meses atendidas pelo sistema de saúde, nota-se que é maior em São Paulo a proporção das mães que iniciam a amamentação e a prevalência de amamentados. A duração média do aleitamento materno total (AM) e quase exclusivo (AE) é respectivamente de 127,5 e 66,6 dias em São Paulo. Em Recife, 104,4 e 31,7 dias, respectivamente, para AM e AE. Estudaram-se também os dados de amamentação conforme a cor da pele da mãe, concluindo que se amamenta mais em São Paulo do que em Recife, significativamente entre brancas. O aleitamento materno quase exclusivo é praticado mais em São Paulo do que em Recife, por brancas e pardas. Observando-se os grupos étnicos em cada uma das cidades, notou-se que são as mulheres não-brancas (pretas e pardas) aquelas que amamentam mais, sendo particularmente baixo o aleitamento quase exclusivo em Recife, maior entre as pretas (34,5 dias de mediana de AE) comparado a 15,3 dias entre brancas e 16,7 entre pardas. O estudo aponta para a necessidade de se elaborar desenhos de pesquisa que levem em conta a questão da etnia e a amamentação, questão não respondida pela literatura em nível mundial
    corecore