422 research outputs found

    Protein folding mediated by solvation: water expelling and formation of the hydrophobic core occurs after the structure collapse

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    The interplay between structure-search of the native structure and desolvation in protein folding has been explored using a minimalist model. These results support a folding mechanism where most of the structural formation of the protein is achieved before water is expelled from the hydrophobic core. This view integrates water expulsion effects into the funnel energy landscape theory of protein folding. Comparisons to experimental results are shown for the SH3 protein. After the folding transition, a near-native intermediate with partially solvated hydrophobic core is found. This transition is followed by a final step that cooperatively squeezes out water molecules from the partially hydrated protein core.Comment: Proceedings of the National Academy of Science, 2002, Vol.99. 685-69

    Effect of central nervous system (CNS) metastases in a real-world multicenter cohort study of Spanish ALK-positive non-small cell lung cancer (NSCLC) patients (p)

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    Background: CNS is a common site of metastases in patients with ALK-positive NSCLC. CNS metastases are associated with a number of deleterious effects, such as reduction in quality of life. However, the relationship between brain metastases and prognosis remains unclear. We aimed to evaluate the effect of CNS metastases on overall survival (OS) in a multicenter cohort of Spanish ALK-positive NSCLC patients diagnosed between 2008 and 2017. Methods: We included patients with stage IV at diagnoses, followed up to April 2018; OS (months [m]) was estimated with the Kaplan-Meier method. Survival curves were compared between groups of patients using the log-rank test. Hazard risk (HR) to death was estimated with multivariable Cox model. Results: Out of 163 patients in the cohort, a total of 116 were evaluated, with a median of follow-up of 29.2 m and 59 deaths reported. Characteristics at diagnosis were a median age of 58 years, 50% female, 58.6% never-smokers, 54.3% with comorbidities, PS by ECOG 0-1 93.1%. CNS metastases (median number of lesions 6) were present in 43.1% of patients and 34% of patients with CNS metastases were treated with local therapy (11.8 % local radiotherapy and 76.5% holocraneal radiotherapy). ALK inhibitors as first line and second line treatment were administered to 45.5% and 78.6% of patients, respectively. The median OS was 39 months; OS in patients with CNS metastases at diagnosis was 34.4 m and 39.0 m in those without CNS metastases at diagnosis (p=.9). In patients without CNS metastases at baseline (n=60), 22 developed CNS, with a median OS greater than in those without CNS metastases during follow-up, although the difference is not significant (45.5 m vs 33.3 m; p=.9). There were 81 patients who presented with metastases in more than one organ and 33 patients with metastases in a single organ. The risk of death increased as the number of metastatic organs at diagnoses increased (HR=1.26, p=.0305), with worse OS in those presenting with liver metastases at diagnoses (21.1%, OS: 20 m), compared to those without tumor involvement (OS: 45.4 m; p =.008). Conclusions: OS was similar for ALK-positive NSCLC patients with and without CNS metastases at diagnoses. OS was worse as the number of metastatic organs at diagnosis increased, with liver metastases being associated with the highest risk of mortality

    Model-independent evidence for J/ψpJ/\psi p contributions to Λb0J/ψpK\Lambda_b^0\to J/\psi p K^- decays

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    The data sample of Λb0J/ψpK\Lambda_b^0\to J/\psi p K^- decays acquired with the LHCb detector from 7 and 8~TeV pppp collisions, corresponding to an integrated luminosity of 3 fb1^{-1}, is inspected for the presence of J/ψpJ/\psi p or J/ψKJ/\psi K^- contributions with minimal assumptions about KpK^- p contributions. It is demonstrated at more than 9 standard deviations that Λb0J/ψpK\Lambda_b^0\to J/\psi p K^- decays cannot be described with KpK^- p contributions alone, and that J/ψpJ/\psi p contributions play a dominant role in this incompatibility. These model-independent results support the previously obtained model-dependent evidence for Pc+J/ψpP_c^+\to J/\psi p charmonium-pentaquark states in the same data sample.Comment: 21 pages, 12 figures (including the supplemental section added at the end

    Updating the Food-Based Dietary Guidelines for the Spanish Population: The Spanish Society of Community Nutrition (SENC) Proposal

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    Diet-related risk factors and physical inactivity are among the leading risk factors for disability and are responsible for a large proportion of the burden of chronic non-communicable diseases. Food-based dietary guidelines (FBDGs) are useful tools for nutrition policies and public health strategies to promote healthier eating and physical activity. In this paper, we discuss the process followed in developing the dietary guidelines for the Spanish population by the Spanish Society of Community Nutrition (SENC) and further explain the collaboration with primary healthcare practitioners as presented in the context of the NUTRIMAD 2018 international congress of SENC. From a health in all policies approach, SENC convened a group of experts in nutrition and public health to review the evidence on diet-health, nutrient intake and food consumption in the Spanish population, as well as food preparation, determinants and impact of diet on environmental sustainability. The collaborative group drafted the document and designed the graphic icon, which was then subject to a consultation process, discussion, and qualitative evaluation. Next, a collaborative group was established to plan a dissemination strategy, involving delegates from all the primary healthcare scientific societies in Spain. A product of this collaboration was the release of an attractive, easy-to-understand publication

    Quantum numbers of the X(3872)X(3872) state and orbital angular momentum in its ρ0Jψ\rho^0 J\psi decay

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    Angular correlations in B+X(3872)K+B^+\to X(3872) K^+ decays, with X(3872)ρ0J/ψX(3872)\to \rho^0 J/\psi, ρ0π+π\rho^0\to\pi^+\pi^- and J/ψμ+μJ/\psi \to\mu^+\mu^-, are used to measure orbital angular momentum contributions and to determine the JPCJ^{PC} value of the X(3872)X(3872) meson. The data correspond to an integrated luminosity of 3.0 fb1^{-1} of proton-proton collisions collected with the LHCb detector. This determination, for the first time performed without assuming a value for the orbital angular momentum, confirms the quantum numbers to be JPC=1++J^{PC}=1^{++}. The X(3872)X(3872) is found to decay predominantly through S wave and an upper limit of 4%4\% at 95%95\% C.L. is set on the fraction of D wave.Comment: 16 pages, 4 figure

    Search for squarks and gluinos with the ATLAS detector in final states with jets and missing transverse momentum using √s=8 TeV proton-proton collision data

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    A search for squarks and gluinos in final states containing high-p T jets, missing transverse momentum and no electrons or muons is presented. The data were recorded in 2012 by the ATLAS experiment in s√=8 TeV proton-proton collisions at the Large Hadron Collider, with a total integrated luminosity of 20.3 fb−1. Results are interpreted in a variety of simplified and specific supersymmetry-breaking models assuming that R-parity is conserved and that the lightest neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 1330 GeV for a simplified model incorporating only a gluino and the lightest neutralino. For a simplified model involving the strong production of first- and second-generation squarks, squark masses below 850 GeV (440 GeV) are excluded for a massless lightest neutralino, assuming mass degenerate (single light-flavour) squarks. In mSUGRA/CMSSM models with tan β = 30, A 0 = −2m 0 and μ > 0, squarks and gluinos of equal mass are excluded for masses below 1700 GeV. Additional limits are set for non-universal Higgs mass models with gaugino mediation and for simplified models involving the pair production of gluinos, each decaying to a top squark and a top quark, with the top squark decaying to a charm quark and a neutralino. These limits extend the region of supersymmetric parameter space excluded by previous searches with the ATLAS detector

    Search for direct stau production in events with two hadronic tau-leptons in root s=13 TeV pp collisions with the ATLAS detector

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    A search for the direct production of the supersymmetric partners ofτ-leptons (staus) in final stateswith two hadronically decayingτ-leptons is presented. The analysis uses a dataset of pp collisions corresponding to an integrated luminosity of139fb−1, recorded with the ATLAS detector at the LargeHadron Collider at a center-of-mass energy of 13 TeV. No significant deviation from the expected StandardModel background is observed. Limits are derived in scenarios of direct production of stau pairs with eachstau decaying into the stable lightest neutralino and oneτ-lepton in simplified models where the two staumass eigenstates are degenerate. Stau masses from 120 GeV to 390 GeV are excluded at 95% confidencelevel for a massless lightest neutralino

    Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics

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    A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential for a variety of interesting physics processes, within the Standard Model and beyond, is examined. The study comprises a series of notes based on simulations of the detector and physics processes, with particular emphasis given to the data expected from the first years of operation of the LHC at CERN

    Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 8 TeV pp collisions with the ATLAS detector

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    A search for the direct production of charginos and neutralinos in final states with three leptons and missing transverse momentum is presented. The analysis is based on 20.3 fb−1 of s√ = 8 TeV proton-proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with the Standard Model expectations and limits are set in R-parity-conserving phenomenological Minimal Supersymmetric Standard Models and in simplified supersymmetric models, significantly extending previous results. For simplified supersymmetric models of direct chargino (χ˜±1) and next-to-lightest neutralino (χ˜02) production with decays to lightest neutralino (χ˜01) via either all three generations of sleptons, staus only, gauge bosons, or Higgs bosons, (χ˜±1) and (χ˜02) masses are excluded up to 700 GeV, 380 GeV, 345 GeV, or 148 GeV respectively, for a massless (χ˜01
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