2,322 research outputs found

    Computation of diffuse scattering arising from one-phonon excitations in a neutron time-of-flight single-crystal Laue diffraction experiment

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    Direct phonon excitation in a neutron time-of-flight single-crystal Laue diffraction experiment has been observed in a single crystal of NaCl. At room temperature both phonon emission and excitation leave characteristic features in the diffuse scattering and these are well reproduced using ab initio phonons from density functional theory (DFT). A measurement at 20 K illustrates the effect of thermal population of the phonons, leaving the features corresponding to phonon excitation and strongly suppressing the phonon annihilation. A recipe is given to compute these effects combining DFT results with the geometry of the neutron experiment

    Robot-assisted kidney transplantation with regional hypothermia using grafts with Multiple Vessels After Extracorporeal Vascular Reconstruction: results from the European Association of Urology Robotic Urology Section Working Group

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    Background: Kidney transplantation using grafts with multiple vessels (GMVs) is technically demanding and may be associated with increased risk of complications or suboptimal graft function. To date, no studies have reported on robot-assisted kidney transplantation (RAKT) using GMVs. Objective: To report our experience with RAKT using GMVs from living donors, focusing on technical feasibility and early postoperative outcomes. Design, setting, and participants: We reviewed the multi-institutional, prospectively collected European Association of Urology (EAU) Robotic Urology Section (ERUS)-RAKT database to select consecutive patients undergoing RAKT from living donors using GMVs between July 2015 and January 2018. Patients undergoing RAKT using grafts with single vessels (GSVs) served as controls. In case of GMVs, ex vivo vascular reconstruction techniques were performed during bench surgery according to the case-specific anatomy. Intervention: RAKT with regional hypothermia. Outcome measurements and statistical analysis: Intraoperative outcomes and early (30 d) postoperative complications and functional results were the main study endpoints. Multivariable logistic regression analysis evaluated potential predictors of suboptimal renal function at 1 mo. Results and limitations: Overall, 148 RAKTs were performed during the study period. Of these, 21/148 (14.2%) used GMVs; in all cases, single arterial and venous anastomoses could be performed after vascular reconstruction. Median anastomoses and rewarming times did not differ significantly between the GMV and GSV groups. Total and cold ischemia times were significantly higher in the GMV cohort (112 vs 88 min, p = 0.004 and 50 vs 34 min, p = 0.003, respectively). Overall complication rate and early functional outcomes were similar among the two groups. No major intra-or postoperative complications were recorded in the GMV cohort. At multivariable analysis, use of GMVs was not significantly associated with suboptimal renal function at 1 mo. Small sample size and short follow-up represent the main study limitations. Conclusions: RAKT using GMVs from living donors is technically feasible and achieved favorable perioperative and short-term functional outcomes. Larger studies with longer follow-up are needed to confirm our findings. Patient summary: In this study, we evaluated for the first time in literature the results of RAKT from living donors using kidneys with multiple arteries and veins. We found that, in experienced centers, RAKT using kidneys with multiple vessels is feasible and achieves optimal results in terms of postoperative kidney function with a low number of postoperative complications. (C) 2018 European Association of Urology. Published by Elsevier B.V. All rights reserved

    Beyond Λ\LambdaCDM constraints from the full shape clustering measurements from BOSS and eBOSS

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    We analyse the full shape of anisotropic clustering measurements from the extended Baryon Oscillation Spectroscopic survey (eBOSS) quasar sample together with the combined galaxy sample from the Baryon Oscillation Spectroscopic Survey (BOSS). We obtain constraints on the cosmological parameters independent of the Hubble parameter hh for the extensions of the Λ\LambdaCDM models, focusing on cosmologies with free dark energy equation of state parameter ww. We combine the clustering constraints with those from the latest CMB data from Planck to obtain joint constraints for these cosmologies for ww and the additional extension parameters - its time evolution waw_{\rm{a}}, the physical curvature density ωK\omega_{K} and the neutrino mass sum ∑mÎœ\sum m_{\nu}. Our joint constraints are consistent with flat Λ\LambdaCDM cosmological model within 68\% confidence limits. We demonstrate that the Planck data are able to place tight constraints on the clustering amplitude today, σ12\sigma_{12}, in cosmologies with varying ww and present the first constraints for the clustering amplitude for such cosmologies, which is found to be slightly higher than the Λ\LambdaCDM value. Additionally, we show that when we vary ww and allow for non-flat cosmologies and the physical curvature density is used, Planck prefers a curved universe at 4σ4\sigma significance, which is ∌2σ\sim2\sigma higher than when using the relative curvature density ΩK\Omega_{\rm{K}}. Finally, when ww is varied freely, clustering provides only a modest improvement (of 0.021 eV) on the upper limit of ∑mÎœ\sum m_{\nu}.Comment: 12 pages, 6 figures, submitted to MNRA

    The structures of E. coli NfsA bound to the antibiotic nitrofurantoin; to 1,4-benzoquinone and to FMN

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    NfsA is a dimeric flavoprotein that catalyses the reduction in nitroaromatics and quinones by NADPH. This reduction is required for the activity of nitrofuran antibiotics. The crystal structure of free Escherichia coli NfsA and several homologues have been determined previously, but there is no structure of the enzyme with ligands. We present here crystal structures of oxidised E. coli NfsA in the presence of several ligands, including the antibiotic nitrofurantoin. Nitrofurantoin binds with the furan ring, rather than the nitro group that is reduced, near the N5 of the FMN. Molecular dynamics simulations show that this orientation is only favourable in the oxidised enzyme, while potentiometry suggests that little semiquinone is formed in the free protein. This suggests that the reduction occurs by direct hydride transfer from FMNH(−) to nitrofurantoin bound in the reverse orientation to that in the crystal structure. We present a model of nitrofurantoin bound to reduced NfsA in a viable hydride transfer orientation. The substrate 1,4-benzoquinone and the product hydroquinone are positioned close to the FMN N5 in the respective crystal structures with NfsA, suitable for reaction, but are mobile within the active site. The structure with a second FMN, bound as a ligand, shows that a mobile loop in the free protein forms a phosphate-binding pocket. NfsA is specific for NADPH and a similar conformational change, forming a phosphate-binding pocket, is likely to also occur with the natural cofactor

    Mapping the human cortical surface by combining quantitative T(1) with retinotopy

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    We combined quantitative relaxation rate (R1= 1/T1) mapping-to measure local myelination-with fMRI-based retinotopy. Gray-white and pial surfaces were reconstructed and used to sample R1 at different cortical depths. Like myelination, R1 decreased from deeper to superficial layers. R1 decreased passing from V1 and MT, to immediately surrounding areas, then to the angular gyrus. High R1 was correlated across the cortex with convex local curvature so the data was first "de-curved". By overlaying R1 and retinotopic maps, we found that many visual area borders were associated with significant R1 increases including V1, V3A, MT, V6, V6A, V8/VO1, FST, and VIP. Surprisingly, retinotopic MT occupied only the posterior portion of an oval-shaped lateral occipital R1 maximum. R1 maps were reproducible within individuals and comparable between subjects without intensity normalization, enabling multi-center studies of development, aging, and disease progression, and structure/function mapping in other modalities

    Impact of COVID-19-Related Lockdown on Psychosocial, Cognitive, and Functional Well-Being in Adults With Down Syndrome

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    People with Down Syndrome (DS) have a high prevalence of physical and psychiatric comorbidities and experience early-onset dementia. With the outbreak of CoVID-19 pandemic, strict social isolation measures have been necessary to prevent the spreading of the disease. Effects of this lockdown period on behavior, mood and cognition in people with DS have not been assessed so far. In the present clinical study, we investigated the impact of CoVID-19-related lockdown on psychosocial, cognitive and functional well-being in a sample population of 46 adults with DS. The interRAI Intellectual Disability standardized assessment instrument, which includes measures of social withdrawal, functional impairment, aggressive behavior and depressive symptoms, was used to perform a three time-point evaluation (two pre-lockdown and one post-lockdown) in 37 subjects of the study sample, and a two time point evaluation (one pre- and one post-lockdown) in 9 subjects. Two mixed linear regression models - one before and one after the lockdown - have been fitted for each scale in order to investigate the change in the time-dependent variation of the scores. In the pre-lockdown period, significant worsening over time (i.e., per year) was found for the Depression Rating Scale score (beta = 0.55; 95% CI 0.34; 0.76). In the post-lockdown period, a significant worsening in social withdrawal (beta = 3.05, 95% CI 0.39; 5.70), instrumental activities of daily living (beta = 1.13, 95% CI 0.08; 2.18) and depression rating (beta = 1.65, 95% CI 0.33; 2.97) scales scores was observed, as was a significant improvement in aggressive behavior (beta = -1.40, 95% CI -2.69; -0.10). Despite the undoubtful importance of the lockdown in order to reduce the spreading of the CoVID-19 pandemic, the related social isolation measures suggest an exacerbation of depressive symptoms and a worsening in functional status in a sample of adults with DS. At the opposite, aggressive behavior was reduced after the lockdown period. This finding could be related to the increase of negative and depressive symptoms in the study population. Studies with longer follow-up period are needed to assess persistence of these effects

    The affective modulation of motor awareness in anosognosia for hemiplegia : Behavioural and lesion evidence

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    © 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).The possible role of emotion in anosognosia for hemiplegia (i.e., denial of motor deficits contralateral to a brain lesion), has long been debated between psychodynamic and neurocognitive theories. However, there are only a handful of case studies focussing on this topic, and the precise role of emotion in anosognosia for hemiplegia requires empirical investigation. In the present study, we aimed to investigate how negative and positive emotions influence motor awareness in anosognosia. Positive and negative emotions were induced under carefully-controlled experimental conditions in right-hemisphere stroke patients with anosognosia for hemiplegia (n = 11) and controls with clinically normal awareness (n = 10). Only the negative, emotion induction condition resulted in a significant improvement of motor awareness in anosognosic patients compared to controls; the positive emotion induction did not. Using lesion overlay and voxel-based lesion-symptom mapping approaches, we also investigated the brain lesions associated with the diagnosis of anosognosia, as well as with performance on the experimental task. Anatomical areas that are commonly damaged in AHP included the right-hemisphere motor and sensory cortices, the inferior frontal cortex, and the insula. Additionally, the insula, putamen and anterior periventricular white matter were associated with less awareness change following the negative emotion induction. This study suggests that motor unawareness and the observed lack of negative emotions about one's disabilities cannot be adequately explained by either purely motivational or neurocognitive accounts. Instead, we propose an integrative account in which insular and striatal lesions result in weak interoceptive and motivational signals. These deficits lead to faulty inferences about the self, involving a difficulty to personalise new sensorimotor information, and an abnormal adherence to premorbid beliefs about the body.Peer reviewedFinal Published versio

    Genetic deletion of the adaptor protein p66Shc increases susceptibility to short-term ischaemic myocardial injury via intracellular salvage pathways

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    Genetic deletion of p66Shc, as shown in the present study, leads to increased myocardial infarction in response to short-term ischaemia and reperfusion. Therefore, heart-specific activation of p66Shc protein may represent a promising novel strategy to prevent ischaemic and reperfusion myocardial injury. In particular, pharmacological modulation of apoptosis via myocardial salvage pathways involving p66Shc might be a promising approach to limit short-term ischaemic injury, for instance in patients with acute coronary syndrome (ACS) from the time of symptom onset to percutaneous coronary intervention. However, the present study also adds complexity to the use of this pathway as a therapeutic target. Indeed, given the different effects of activation and silencing of p66Shc in different cells, tissues and organs, tissue selective inhibition would be required. Indeed, while short-term activation might be protective in the context of an ACS, long-term inhibition may prevent endothelial dysfunction, atherosclerosis, and diabetic vascular disease. Obviously, this complexity also raises safety concerns for the potential use of p66Shc in acute myocardial infarction that need to be clarified by additional researc

    Survey of Demographic and Phenotypic Data of Local Pig Breeds of Treasure Project

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    Local genetic resources represent an important reservoir of biodiversity in the animal sector. Sustainable use of these resources can be an important source of income for farmers taking advantage of the peculiar characteristics of their products

    The zCOSMOS 10k-Bright Spectroscopic Sample

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    We present spectroscopic redshifts of a large sample of galaxies with I_(AB) < 22.5 in the COSMOS field, measured from spectra of 10,644 objects that have been obtained in the first two years of observations in the zCOSMOS-bright redshift survey. These include a statistically complete subset of 10,109 objects. The average accuracy of individual redshifts is 110 km s^(–1), independent of redshift. The reliability of individual redshifts is described by a Confidence Class that has been empirically calibrated through repeat spectroscopic observations of over 600 galaxies. There is very good agreement between spectroscopic and photometric redshifts for the most secure Confidence Classes. For the less secure Confidence Classes, there is a good correspondence between the fraction of objects with a consistent photometric redshift and the spectroscopic repeatability, suggesting that the photometric redshifts can be used to indicate which of the less secure spectroscopic redshifts are likely right and which are probably wrong, and to give an indication of the nature of objects for which we failed to determine a redshift. Using this approach, we can construct a spectroscopic sample that is 99% reliable and which is 88% complete in the sample as a whole, and 95% complete in the redshift range 0.5 < z < 0.8. The luminosity and mass completeness levels of the zCOSMOS-bright sample of galaxies is also discussed
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