191 research outputs found

    Refined Tectonic Evolution of the Betic-Rif Orogen Through Integrated 3-D Microstructural Analysis and Sm-Nd Dating of Garnet Porphyroblasts

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    Acknowledgments The authors would like to thank Ángel Perandrés-Villegas for preparing the thin sections used for this study, Fátima Linares Ordóñez for X-ray computed micro-tomography scanning, Mike Tappa for assistance with thermal ionization mass spectrometry analysis, Francisco Alonso-Chaves and Fernando Simancas for sending structural data, Whitney Behr, Johannes Glodny, Sean Mulcahy, and an anonymous reviewer for providing helpful reports, and editors Laurent Jolivet and Federico Rossetti for additional comments that helped improve two earlier manuscript versions. EFB gratefully acknowledges support from the NSF Grants EAR-1250497 and PIRE-1545903 as well as start up funds from the Boston College. DA and ARF gratefully acknowledge financial support through Spanish project “DAMAGE” (CGL2016-80687-R AEI/FEDER), and Junta de Andalucía project RNM148, both directed by Jesús Galindo Zaldivar. ARF acknowledges an PhD Grant (FPU) from the Spanish government. Open access fees have been funded by Universidad de Granada /CBUA.High-resolution microstructural analysis of porphyroblast inclusion trails integrated with Sm-Nd garnet geochronology has provided new insight into the tectonic history of the Betic-Rif orogen. Three principal age groups of porphyroblasts are demonstrated with distinctly oriented inclusion-trails. Inclusion-trail curvature axes or “FIA” (Foliation Inflexion/Intersection Axes) are shown to represent “fossilized” crenulation axes from which a succession of different crustal shortening directions can be deduced. The regional consistency of microstructural orientations and their geometric relationship with multiple sets of macroscopic folds reveal the composite character of the Gibraltar Arc formed by a superposition of different folding directions and associated lineations. Bulk-garnet ages of 35–22 Ma obtained from five micaschist samples of the Alpujarride-Sebtide complex (ASC) and of 35–13 Ma from four micaschists of the Nevado-Filabride complex (NFC) allow to deduce NNE-SSW directed shortening in the Late Eocene changing to NW-SE shortening in the early Oligocene, alternating with suborthogonal NE-SW shortening during the Miocene. These directions can be related to a major swing in the direction of relative Africa-Iberia plate-motion known from kinematic modeling of magnetic seafloor anomalies, and subsequent dynamic interference between plate convergence and suborthogonal “tectonic escape” of the Alboran Domain. Coupled to previously established P-T-t paths, the new garnet ages support a common tectono-metamorphic evolution of the ASC and NFC as laterally equivalent orogenic domains until, in the Miocene, the second became re-buried under the first.NSF Grant EAR-1250497PIRE-1545903Spanish project “DAMAGE” (CGL2016-80687-R AEI/FEDER)Junta de Andalucía project RNM148PhD Grant (FPU) from the Spanish governmentOpen access fees have been funded by Universidad de Granada /CBU

    An evaluation of advanced access in general practice

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    Aims: To evaluate ‘Advanced Access’ in general practice, and assess its impact on patients, practice organisation, activity, and staff.Objectives: To describe the range of strategies that general practices have employed to improve access to care To determine the impact of Advanced Access on the wait for an appointment, continuity of care, practice workload, and demand on other NHS services. To explore the perceptions of different groups of patients, including both users and non-users of services, about the accessibility of care and their satisfaction with access to care in relation to different models of organisation. To explore the trade-offs that patients make between speed of access, continuity of care and other factors when making an appointment in general practice. To explore the perceptions of general practitioners and receptionists about working with the NPDT and implementing changes to practice arrangements to improve access. To assess the impact of the above changes in practice organisation on staff job satisfaction and team climate.Method and results: This research was based on a comparison of 48 general practices, half of which operated Advanced Access appointment systems and half of which did not (designated ‘control’ practices). These practices were recruited from 12 representative Primary Care Trusts (PCTs). From within these 48 practices, eight (four Advanced Access and four control) were selected for in-depth case study using an ethnographic approach. The research was comprised of several component studies. These included: • A survey of all practices in 12 PCTs. Based on this we recruited the 24 Advanced Access and 24 control practices and the 8 case study practices. • An assessment of appointments available and patients seen, based on appointments records • An assessment of continuity of care based on patients’ records • Random phone calls to practices to assess ability to make an appointment by telephone • A questionnaire survey of patients attending the practices • A postal survey of patients who had not attended the surgery in the previous 12 months • A discrete choice experiment to explore trade-offs patients make between access and other factors • A survey of practice staff • Qualitative case studies in 8 practices • Interviews with PCT access facilitators The methods and results for each of these studies are described below, in relation to each of the research objectives.<br/

    A reconnaissance-scale GIS-based multicriteria decision analysis to support sustainable biochar use: Poland as a case study

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    Although increasing numbers of research papers regarding biochar are being published worldwide, in some countries growing interest in biochar has only recently been observed; this is true of Poland. We analysed information on biochar research in Poland alongside lessons learned elsewhere in order to identify the significant opportunities and risks associated with biochar use. This data fed into a GIS-based multicriteria analysis to identify areas where biochar application could deliver greatest benefit. We found that 21.8% of agricultural land in Poland has at least moderate indication for biochar use (soil organic matter below 2% and pH below 5.5), while 1.5% was categorized as a priority as it also exhibited contamination. Potential barriers identified included biomass availability and associated risks of indirect land-use change due to possible national and transnational biomass production displacement. Biochar use could have positive global consequences as a climate change mitigation strategy, particularly relevant in a country with limited alternatives. Scaling up a mitigation technology that is viable on account of its co-benefits might be cost-effective, which could, in turn, adjust national perspectives and stronger involvement in developing mitigation policies at the regional level. Biochar has much promise in temperate conditions and further research should therefore be assigned to explore biochar’s environmental and socio-economic impacts

    The state of the Martian climate

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    60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

    Combination antiretroviral therapy and the risk of myocardial infarction

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    Microbialite response to an anthropogenic salinity gradient in Great Salt Lake, Utah.

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    A railroad causeway across Great Salt Lake, Utah (GSL), has restricted water flow since its construction in 1959, resulting in a more saline North Arm (NA; 24%-31% salinity) and a less saline South Arm (SA; 11%-14% salinity). Here, we characterized microbial carbonates collected from the SA and the NA to evaluate the effect of increased salinity on community composition and abundance and to determine whether the communities present in the NA are still actively precipitating carbonate or if they are remnant features from prior to causeway construction. SSU rRNA gene abundances associated with the NA microbialite were three orders of magnitude lower than those associated with the SA microbialite, indicating that the latter community is more productive. SSU rRNA gene sequencing and functional gene microarray analyses indicated that SA and NA microbialite communities are distinct. In particular, abundant sequences affiliated with photoautotrophic taxa including cyanobacteria and diatoms that may drive carbonate precipitation and thus still actively form microbialites were identified in the SA microbialite; sequences affiliated with photoautotrophic taxa were in low abundance in the NA microbialite. SA and NA microbialites comprise smooth prismatic aragonite crystals. However, the SA microbialite also contained micritic aragonite, which can be formed as a result of biological activity. Collectively, these observations suggest that NA microbialites are likely to be remnant features from prior to causeway construction and indicate a strong decrease in the ability of NA microbialite communities to actively precipitate carbonate minerals. Moreover, the results suggest a role for cyanobacteria and diatoms in carbonate precipitation and microbialite formation in the SA of GSL

    Stage II/III rectal cancer with intermediate response to preoperative radiochemotherapy: Do we have indications for individual risk stratification?

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    <p>Abstract</p> <p>Background</p> <p>Response to preoperative radiochemotherapy (RCT) in patients with locally advanced rectal cancer is very heterogeneous. Pathologic complete response (pCR) is accompanied by a favorable outcome. However, most patients show incomplete response. The aim of this investigation was to find indications for risk stratification in the group of intermediate responders to RCT.</p> <p>Methods</p> <p>From a prospective database of 496 patients with rectal adenocarcinoma, 107 patients with stage II/III cancers and intermediate response to preoperative 5-FU based RCT (ypT2/3 and TRG 2/3), treated within the German Rectal Cancer Trials were studied. Surgical treatment comprised curative (R0) total mesorectal excision (TME) in all cases. In 95 patients available for statistical analyses, residual transmural infiltration of the mesorectal compartment, nodal involvement and histolologic tumor grading were investigated for their prognostic impact on disease-free (DFS) and overall survival (OS).</p> <p>Results</p> <p>Residual tumor transgression into the mesorectal compartment (ypT3) did not influence DFS and OS rates (p = 0.619, p = 0.602, respectively). Nodal involvement after preoperative RCT (ypN1/2) turned out to be a valid prognostic factor with decreased DFS and OS (p = 0.0463, p = 0.0236, respectively). Persistent tumor infiltration of the mesorectum (ypT3) and histologic tumor grading of residual tumor cell clusters were strongly correlated with lymph node metastases after neoadjuvant treatment (p < 0.001).</p> <p>Conclusions</p> <p>Advanced transmural tumor invasion after RCT does not affect prognosis when curative (R0) resection is achievable. Residual nodal status is the most important predictor of individual outcome in intermediate responders to preoperative RCT. Furthermore, ypT stage and tumor grading turn out to be additional auxiliary factors. Future clinical trials for risk-adapted adjuvant therapy should be based on a synopsis of clinicopathologic parameters.</p

    Analysis of positional candidate genes in the AAA1 susceptibility locus for abdominal aortic aneurysms on chromosome 19

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    ABSTRACT: BACKGROUND: Abdominal aortic aneurysm (AAA) is a complex disorder with multiple genetic risk factors. Using affected relative pair linkage analysis, we previously identified an AAA susceptibility locus on chromosome 19q13. This locus has been designated as the AAA1 susceptibility locus in the Online Mendelian Inheritance in Man (OMIM) database. METHODS: Nine candidate genes were selected from the AAA1 locus based on their function, as well as mRNA expression levels in the aorta. A sample of 394 cases and 419 controls was genotyped for 41 SNPs located in or around the selected nine candidate genes using the Illumina GoldenGate platform. Single marker and haplotype analyses were performed. Three genes (CEBPG, PEPD and CD22) were selected for DNA sequencing based on the association study results, and exonic regions were analyzed. Immunohistochemical staining of aortic tissue sections from AAA and control individuals was carried out for the CD22 and PEPD proteins with specific antibodies. RESULTS: Several SNPs were nominally associated with AAA (p < 0.05). The SNPs with most significant p-values were located near the CCAAT enhancer binding protein (CEBPG), peptidase D (PEPD), and CD22. Haplotype analysis found a nominally associated 5-SNP haplotype in the CEBPG/PEPD locus, as well as a nominally associated 2-SNP haplotype in the CD22 locus. DNA sequencing of the coding regions revealed no variation in CEBPG. Seven sequence variants were identified in PEPD, including three not present in the NCBI SNP (dbSNP) database. Sequencing of all 14 exons of CD22 identified 20 sequence variants, five of which were in the coding region and six were in the 3'-untranslated region. Five variants were not present in dbSNP. Immunohistochemical staining for CD22 revealed protein expression in lymphocytes present in the aneurysmal aortic wall only and no detectable expression in control aorta. PEPD protein was expressed in fibroblasts and myofibroblasts in the media-adventitia border in both aneurysmal and non-aneurysmal tissue samples. CONCLUSIONS: Association testing of the functional positional candidate genes on the AAA1 locus on chromosome 19q13 demonstrated nominal association in three genes. PEPD and CD22 were considered the most promising candidate genes for altering AAA risk, based on gene function, association evidence, gene expression, and protein expression
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