2,259 research outputs found

    Operative time and outcome of enhanced recovery after surgery after laparoscopic colorectal surgery

    Get PDF
    Background and Objectives: Combining laparoscopy and enhanced recovery provides benefit to short-term outcomes after colorectal surgery. Advances in training and techniques have allowed surgeons to operate on cases that are technically challenging and associated with prolonged operative time. Laparoscopic techniques improve the outcome of enhanced recovery after colorectal surgery; however, there are no specifications on the effect of prolonged operations on the outcome. The objective was to elucidate the impact of prolonged surgery and blood loss on the outcome of enhanced recovery after surgery after laparoscopic colorectal surgery. Methods: Four-hundred patients who underwent elective colorectal resection on enhanced recovery after surgery in Yeovil District Hospital between 2002 and 2009 were retrospectively reviewed. Delayed discharge was defined as a prolonged length of stay beyond the mean in this series (≥8 days). Results: Three-hundred eighty-five patients were included. Median operative time was 180 minutes with a median blood loss of 100 mL. Conversion was not associated with a prolonged length of stay. Operative time and blood loss correlated with length of stay in a stepwise fashion. There were 2 cutoff points of operative time at 160 minutes and 300 minutes (5 hours), where risk of prolonged stay increased significantly (odds ratio [OR] = 2.02; 95% confidence interval [CI], 1.05-3.90; P= 027), and blood loss of >500 mL (OR = 3.114; 95% CI, 1.501-6.462, P =.002). Conclusions: Total operative timing impacts negatively on the outcome of enhanced recovery after laparoscopic colorectal resections with increased risk of delayed discharge seen after ~2.5 hours and 5-hour duration. © 2014 by JSLS, Journal of the Society of Laparoendoscopic Surgeons

    Long‐term trends in the distribution, abundance and impact of native “injurious” weeds

    Get PDF
    Questions: How can we quantify changes in the distribution and abundance of injurious weed species (Senecio jacobaea, Cirsium vulgare, Cirsium arvense, Rumex obtusifolius, Rumex crispus and Urtica dioica), over long time periods at wide geographical scales? What impact do these species have on plant communities? To what extent are changes driven by anthropogenically induced drivers such as disturbance, eutrophication and management? Location: Great Britain. Methods: Data from national surveys were used to assess changes in the frequency and abundance of selected weed species between 1978 and 2007. This involved novel method development to create indices of change, and to relate changes in distribution and abundance of these species to plant community diversity and inferred changes in resource availability, disturbance and management. Results: Three of the six weed species became more widespread in GB over this period and all of them increased in abundance (in grasslands, arable habitats, roadsides and streamsides). Patterns were complex and varied by landscape context and habitat type. For most of the species, there were negative relationships between abundance, total plant species richness, grassland, wetland and woodland indicators. Each individual species responds to a different combination of anthropogenic drivers but disturbance, fertility and livestock management significantly influenced most species. Conclusions: The increase in frequency and abundance of weeds over decades has implications for landscape‐scale plant diversity, fodder yield and livestock health. This includes reductions in plant species richness, loss of valuable habitat specialists and homogenisation of vegetation communities. Increasing land‐use intensity, excessive nutrient input, overgrazing, sward damage, poaching and bare ground in fields and undermanagement or too frequent cutting on linear features may have led to increases in weeds. These weeds do have conservation value so we are not advocating eradication, rather co‐existence, without dominance. Land management policy needs to adapt to benefit biodiversity and agricultural productivity

    A Hydrophobic Gate in an Ion Channel: The Closed State of the Nicotinic Acetylcholine Receptor

    Full text link
    The nicotinic acetylcholine receptor (nAChR) is the prototypic member of the `Cys-loop' superfamily of ligand-gated ion channels which mediate synaptic neurotransmission, and whose other members include receptors for glycine, gamma-aminobutyric acid, and serotonin. Cryo-electron microscopy has yielded a three dimensional structure of the nAChR in its closed state. However, the exact nature and location of the channel gate remains uncertain. Although the transmembrane pore is constricted close to its center, it is not completely occluded. Rather, the pore has a central hydrophobic zone of radius about 3 A. Model calculations suggest that such a constriction may form a hydrophobic gate, preventing movement of ions through a channel. We present a detailed and quantitative simulation study of the hydrophobic gating model of the nicotinic receptor, in order to fully evaluate this hypothesis. We demonstrate that the hydrophobic constriction of the nAChR pore indeed forms a closed gate. Potential of mean force (PMF) calculations reveal that the constriction presents a barrier of height ca. 10 kT to the permeation of sodium ions, placing an upper bound on the closed channel conductance of 0.3 pS. Thus, a 3 A radius hydrophobic pore can form a functional barrier to the permeation of a 1 A radius Na+ ion. Using a united atom force field for the protein instead of an all atom one retains the qualitative features but results in differing conductances, showing that the PMF is sensitive to the detailed molecular interactions.Comment: Accepted by Physical Biology; includes a supplement and a supplementary mpeg movie can be found at http://sbcb.bioch.ox.ac.uk/oliver/download/Movies/watergate.mp

    On the use of parataxonomy in biodiversity monitoring: a case study on wild flora

    Get PDF
    International audienceMonitoring programs that assess species-richness and turnover are now regarded as essential to document biodiversity loss worldwide. Implementation of such programs is impeded by a general decrease in the number of skilled naturalists. Here we studied how morphotypes, instead of species, might be used by unskilled participants (referred to as “volunteers”) to survey common plant communities. Our main questions were: (1) Can morphotypes be used as a robust estimator of species-richness (alpha-diversity) and assemblage turnover (Beta-diversity)? and (2) What is the robustness (reproducibility and repeatability) of such methods? Double inventories were performed on 150 plots in arable Weld margins, one by a non-expert using morphotypes, the other by a taxonomist using species. To test the robustness of morphotype identiWcation among participants, 20 additional plots were surveyed by eight volunteers using the same protocol. We showed that (1) the number of morphotypes identiWed by unskilled volunteers in a plot was always strongly correlated with species-richness. (2) Morphotypes were sensitive to diVerences among habitats but were less accurate than species to detect these diVerences. (3) Morphotype identiWcation varied signiWcantly within and between volunteers. Due to this lack of repeatability and reproducibility, parataxonomy cannot be considered a good surrogate for taxonomy. Nevertheless, assuming that morphotypes are identiWed with standardized methods, and that results are used only to evaluate gross species-richness but not species turnover, parataxonomy might be a valuable tool for rapid biodiversity assessment of common wild flora

    PDBe: towards reusable data delivery infrastructure at protein data bank in Europe

    Get PDF
    © 2017 The Authors. Published by OUP. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1093/nar/gkx1070The Protein Data Bank in Europe (PDBe, pdbe.org) is actively engaged in the deposition, annotation, remediation, enrichment and dissemination of macromolecular structure data. This paper describes new developments and improvements at PDBe addressing three challenging areas: data enrichment, data dissemination and functional reusability. New features of the PDBe Web site are discussed, including a context dependent menu providing links to raw experimental data and improved presentation of structures solved by hybrid methods. The paper also summarizes the features of the LiteMol suite, which is a set of services enabling fast and interactive 3D visualization of structures, with associated experimental maps, annotations and quality assessment information. We introduce a library of Web components which can be easily reused to port data and functionality available at PDBe to other services. We also introduce updates to the SIFTS resource which maps PDB data to other bioinformatics resources, and the PDBe REST API.Wellcome Trust [104948]; UK Biotechnology and Biological Sciences Research Council [BB/M011674/1, BB/N019172/1, BB/M020347/1]; European Union [284209]; European Molecular Biology Laboratory (EMBL). Funding for open access charge: EMBL.Published versio

    Neutrino and Antineutrino Inclusive Charged-current Cross Section Measurements with the MINOS Near Detector

    Get PDF
    The energy dependence of the neutrino-iron and antineutrino-iron inclusive charged-current cross sections and their ratio have been measured using a high-statistics sample with the MINOS Near Detector exposed to the NuMI beam from the Main Injector at Fermilab. Neutrino and antineutrino fluxes were determined using a low hadronic energy subsample of charged-current events. We report measurements of neutrino-Fe (antineutrinoFe) cross section in the energy range 3-50 GeV (5-50 GeV) with precision of 2-8% (3-9%) and their ratio which is measured with precision 2-8%. The data set spans the region from low energy, where accurate measurements are sparse, up to the high-energy scaling region where the cross section is well understood.Comment: accepted by PR

    A Study of Muon Neutrino Disappearance Using the Fermilab Main Injector Neutrino Beam

    Get PDF
    We report the results of a search for muon-neutrino disappearance by the Main Injector Neutrino Oscillation Search. The experiment uses two detectors separated by 734 km to observe a beam of neutrinos created by the Neutrinos at the Main Injector facility at Fermi National Accelerator Laboratory. The data were collected in the first 282 days of beam operations and correspond to an exposure of 1.27e20 protons on target. Based on measurements in the Near Detector, in the absence of neutrino oscillations we expected 336 +/- 14 muon-neutrino charged-current interactions at the Far Detector but observed 215. This deficit of events corresponds to a significance of 5.2 standard deviations. The deficit is energy dependent and is consistent with two-flavor neutrino oscillations according to delta m-squared = 2.74e-3 +0.44/-0.26e-3 eV^2 and sin^2(2 theta) > 0.87 at 68% confidence level.Comment: In submission to Phys. Rev.

    Testing Lorentz Invariance and CPT Conservation with NuMI Neutrinos in the MINOS Near Detector

    Get PDF
    A search for a sidereal modulation in the MINOS near detector neutrino data was performed. If present, this signature could be a consequence of Lorentz and CPT violation as predicted by a class of extensions to the Standard Model. No evidence for a sidereal signal in the data set was found, implying that there is no significant change in neutrino propagation that depends on the direction of the neutrino beam in a sun-centered inertial frame. Upper limits on the magnitudes of the Lorentz and CPT violating terms in these extensions to the Standard Model lie between 0.01-1% of the maximum expected, assuming a suppression of these signatures by factor of 101710^{-17}.
    corecore