372 research outputs found

    Present-day stress orientations and tectonic provinces of the NW Borneo collisional margin

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    Extent: 15p.Borehole failure observed on image and dipmeter logs from 55 petroleum wells across the NW Borneo collisional margin were used to determine maximum horizontal stress (σH) orientations; combined with seismic and outcrop data, they define seven tectonic provinces. The Baram Delta–Deepwater Fold-Thrust Belt exhibits three tectonic provinces: its inner shelf inverted province (σH is NW-SE, margin-normal), its outer shelf extension province (σH is NE-SW, margin-parallel), and its slope to basin floor compression province (σH is NW-SE, margin-normal). In the inverted province, σH reflects inversion of deltaic normal faults. The σH orientations in the extension and compression provinces reflect deltaic gravitational tectonics. The shale and minibasin provinces have been recognized in offshore Sabah. In the shale province, σH is N010°E, which aligns around the boundary of a massif of mobile shale. Currently, no data are available to determine σH in the minibasin province. In the Balingian province, σH is ESE-WNW, reflecting ESE absolute Sunda plate motions due to the absence of a thick detachment seen elsewhere in NW Borneo. The Central Luconia province demonstrates poorly constrained and variable σH orientations. These seven provinces result from the heterogeneous structural and stratigraphic development of the NW Borneo margin and formed due to complex collisional tectonics and the varied distribution and thicknesses of stratigraphic packages.Rosalind C. King, Mark R. P. Tingay, Richard R. Hillis, Christopher K. Morley, and James Clar

    Pure Cerebellar Ataxia with Homozygous Mutations in the PNPLA6 Gene

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    Autosomal-recessive cerebellar ataxias (ARCA) are clinically and genetically heterogeneous conditions primarily affecting the cerebellum. Mutations in the PNPLA6 gene have been identified as the cause of hereditary spastic paraplegia and complex forms of ataxia associated with retinal and endocrine manifestations in a field where the genotype-phenotype correlations are rapidly expanding. We identified two cousins from a consanguineous family belonging to a large Zoroastrian (Parsi) family residing in Mumbai, India, who presented with pure cerebellar ataxia without chorioretinal dystrophy or hypogonadotropic hypogonadism. We used a combined approach of clinical characterisation, homozygosity mapping, whole-exome and Sanger sequencing to identify the genetic defect in this family. The phenotype in the family was pure cerebellar ataxia. Homozygosity mapping revealed one large region of shared homozygosity at chromosome 19p13 between affected individuals. Within this region, whole-exome sequencing of the index case identified two novel homozygous missense variants in the PNPLA6 gene at c.3847G>A (p.V1283M) and c.3929A>T (p.D1310V) in exon 32. Both segregated perfectly with the disease in this large family, with only the two affected cousins being homozygous. We identified for the first time PNPLA6 mutations associated with pure cerebellar ataxia in a large autosomal-recessive Parsi kindred. Previous mutations in this gene have been associated with a more complex phenotype but the results here suggest an extension of the associated disease spectrum

    Seroepidemiologic studies of hantavirus infection among wild rodents in California.

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    A total of 4,626 mammals were serologically tested for antibodies to Sin Nombre virus. All nonrodent species were antibody negative. Among wild rodents, antibody prevalence was 8.5% in murids, 1.4% in heteromyids, and < 0.1% in sciurids. Of 1,921 Peromyscus maniculatus (deer mice), 226 (11.8%) were antibody positive, including one collected in 1975. The highest antibody prevalence (71.4% of 35) was found among P. maniculatus on Santa Cruz Island, off the southern California coast. Prevalence of antibodies among deer mice trapped near sites of human cases (26.8% of 164) was significantly higher than that of mice from other sites (odds ratio = 4.5; 95% confidence interval = 1.7, 11.6). Antibody prevalence increased with rising elevation (> 1,200 meters) and correlated with a spatial cluster of hantavirus pulmonary syndrome cases in the Sierra Nevada

    C-KIT IS EXPRESSED IN SOFT TISSUE SARCOMA OF NEUROECTODERMIC ORIGIN AND ITS LIGAND PREVENTS APOPTOSIS OF NEOPLASTIC CELLS

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    During development, mice with mutations of stem cell factor (SCF) or its receptor c-kit exhibit defects in melanogenesis, as well as hematopoiesis and gonadogenesis. Consequently, accumulating evidence suggests that the c-kit/SCF system plays a crucial role in all of these processes and in tumors which derive from them. Especially in neuroblastoma (infant tumors of neuroectoderm crest derivation such as melano-cytes) it would appear that an autocrine loop exists between c-kit and SCF, and that the functional block of the c-kit receptors with monoclonal antibodies (MoAbs) results in a significant decrease in cellular proliferation. We studied the expression and role of c-kit and SCF in cell lines of soft tissue sarcoma of neuroectodermic origin, such as Ewing’s sar-coma (ES) and peripheral neuro-ectodermal tumors (PNET). Using flow cytometry with MoAb CD117 PE, c-kit expressio

    Promoting Transparency in Social Science Research

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    There is growing appreciation for the advantages of experimentation in the social sciences. Policy-relevant claims that in the past were backed by theoretical arguments and inconclusive correlations are now being investigated using more credible methods. Changes have been particularly pronounced in development economics, where hundreds of randomized trials have been carried out over the last decade. When experimentation is difficult or impossible, researchers are using quasi-experimental designs. Governments and advocacy groups display a growing appetite for evidence-based policy-making. In 2005, Mexico established an independent government agency to rigorously evaluate social programs, and in 2012, the U.S. Office of Management and Budget advised federal agencies to present evidence from randomized program evaluations in budget requests (1, 2)

    Improving the coverage of the PMTCT programme through a participatory quality improvement intervention in South Africa

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    <p>Abstract</p> <p>Background</p> <p>Despite several years of implementation, prevention of mother-to-child transmission (PMTCT) programmes in many resource poor settings are failing to reach the majority of HIV positive women. We report on a data driven participatory quality improvement intervention implemented in a high HIV prevalence district in South Africa.</p> <p>Methods</p> <p>A participatory quality improvement intervention was implemented consisting of an initial assessment undertaken by a team of district supervisors, workshops to assess results, identify weaknesses and set improvement targets and continuous monitoring to support changes.</p> <p>Results</p> <p>The assessment highlighted weaknesses in training and supervision. Routine data revealed poor coverage of all programme indicators except HIV testing. Monthly support to all facilities took place including an orientation to the PMTCT protocol, review of local data and identification of bottlenecks to optimal coverage using a continuous quality improvement approach. One year following the intervention large improvements in programme indicators were observed. Coverage of CD4 testing increased from 40 to 97%, uptake of maternal nevirapine from 57 to 96%, uptake of infant nevirapine from 15 to 68% and six week PCR testing from 24 to 68%.</p> <p>Conclusion</p> <p>It is estimated that these improvements in coverage could avert 580 new infant infections per year in this district. This relatively simple participatory assessment and intervention process has enabled programme managers to use a data driven approach to improve the coverage of this important programme.</p

    Defining features of the practice of global health research: an examination of 14 global health research teams

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    Objectives: This paper strives to develop a pragmatic view of the scope of practice and core characteristics of global health research (GHR) by examining the activities of 14 Canadian-funded global health teams that were in the process of implementing research programs. Methods: Information was collected by a reflective exploration of team proposals and progress reports, a content analysis of the outputs from an all-team meeting and review of the literature. Results: Teams adopted equity-centered, problem-focused, systems-based approaches intended to find upstream determinants that could make people more resilient to social and ecological factors impacting their health. Long-term visions and time frames were needed to develop and solidify fully functional interdisciplinary, multinational, multicultural partnerships. The implementation of research into practice was a motivating factor for all teams, but to do this, they recognized the need for evidence-based advice on how to best do this. Traditional measures of biomedical research excellence were necessary but not sufficient to encompass views of excellence of team-based interdisciplinary research, which includes features like originality, coherence and cumulative contributions to fields of study, acceptance by peers and success in translating research into gains in health status. An innovative and nuanced approached to GHR ethics was needed to deal with some unique ethical issues because the needs for GHR were not adequately addressed by institutional biomedical research ethics boards. Core competencies for GHR researchers were a blend of those needed for health promotion, population health, international development, sustainable development, and systems science. Discussion: Developing acceptable and meaningful ways to evaluate the short-term contributions for GHR and forecast its long-term impacts is a strategic priority needed to defend decisions being made in GHR development. Planning and investing to support the underlying GHR elements and competencies that allow for adaptive, innovative, and supportive research partnerships to achieve &#x2018;health for all&#x2019; are more likely to have long-term impacts than building research strategies around specific diseases of interest
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