514 research outputs found

    Experimental analysis of the effect of a wettability gradient on condensation heat transfer coefficient

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    The use of surfaces with wettability gradient aims to cover the surface with drops of small size to allow a large heat exchange. Thus, the action of the wettability gradient on the surface of the substrate is twofold: on the one hand, it allows the preservation of a dropwise condensation regime for which the heat exchange coefficient is particularly important and, on the other hand it allows the evacuation of the dispersed phase, thus promoting a renewal of the surface with very important heat exchanges during the nucleation phase. Thereby, a heat transfer enhancement factor up to 3.4 has been experimentally measured.Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .International centre for heat and mass transfer.American society of thermal and fluids engineers

    Valor nutricional do mel e pĂłlen de abelhas sem ferrĂŁo da regiĂŁo AmazĂ´nica

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    Avaliou-se os constituintes nutricionais de amostras do mel e pólen das espÊcies Melipona seminigra merrillae (jandaíra), Melipona compressipes manaosensis (juparå), Melipona rufiventris paraensis (uruçu boca de ralo), provenientes do meliponårio da Fazenda Poranga no município de Itacoatiara - AM e Meliponårio Abelhudo em Manaus - AM. Os resultados demonstraram o potencial do mel como fonte de energia, particularmente a M. rufiventris com 305,3¹2,4 kcal em 100g. O pólen da espÊcie M. compressipes apresentou a maior concentração de proteína 15,7¹0,0% e energia 309,8¹0,8 kcal. Tais constataçþes sugerem a implementação de novos estudos visando à incorporação destes produtos na dieta dos amazônidas, possibilitando uma nova fonte alternativa de alimento potencialmente nutritivo e saudåvel.<br>We evaluated the nutricional constituent of honey and pollen samples of the Melipona species seminigra merrillae (jandaíra) Melipona compressipes manaosensis (juparå), Melipona rufiventris paraensis (uruçu boca de ralo), proceeding from the Poranga Honey Farm in Itacoatiara - AM, and Meliponårio Abelhudo in Manaus, AM. The results demonstrated the potencial of honey as a source of energy, particularly the kcal M. rufiventris with 305.3¹2.4 kcal in 100g. The compressis pollen of species presented the highest concentration of protein 15.7¹0.0 % and energy 309.8¹0.8 kcal. Thus we suggest the implementation of new studies aiming at the incorporation of these products in the diet of the Amazon population, making possible a new potentially nutritional and alternative healthful food source

    Crowdsourcing the General Public for Large Scale Molecular Pathology Studies in Cancer

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    Background: Citizen science, scientific research conducted by non-specialists, has the potential to facilitate biomedical research using available large-scale data, however validating the results is challenging. The Cell Slider is a citizen science project that intends to share images from tumors with the general public, enabling them to score tumor markers independently through an internet-based interface. Methods: From October 2012 to June 2014, 98,293 Citizen Scientists accessed the Cell Slider web page and scored 180,172 sub-images derived from images of 12,326 tissue microarray cores labeled for estrogen receptor (ER). We evaluated the accuracy of Citizen Scientist's ER classification, and the association between ER status and prognosis by comparing their test performance against trained pathologists. Findings: The area under ROC curve was 0.95 (95% CI 0.94 to 0.96) for cancer cell identification and 0.97 (95% CI 0.96 to 0.97) for ER status. ER positive tumors scored by Citizen Scientists were associated with survival in a similar way to that scored by trained pathologists. Survival probability at 15 years were 0.78 (95% CI 0.76 to 0.80) for ER-positive and 0.72 (95% CI 0.68 to 0.77) for ER-negative tumors based on Citizen Scientists classification. Based on pathologist classification, survival probability was 0.79 (95% CI 0.77 to 0.81) for ER-positive and 0.71 (95% CI 0.67 to 0.74) for ER-negative tumors. The hazard ratio for death was 0.26 (95% CI 0.18 to 0.37) at diagnosis and became greater than one after 6.5 years of follow-up for ER scored by Citizen Scientists, and 0.24 (95% CI 0.18 to 0.33) at diagnosis increasing thereafter to one after 6.7 (95% CI 4.1 to 10.9) years of follow-up for ER scored by pathologists. Interpretation: Crowdsourcing of the general public to classify cancer pathology data for research is viable, engages the public and provides accurate ER data. Crowdsourced classification of research data may offer a valid solution to problems of throughput requiring human input

    Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

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    Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe

    Measurement of the Lambda(b) cross section and the anti-Lambda(b) to Lambda(b) ratio with Lambda(b) to J/Psi Lambda decays in pp collisions at sqrt(s) = 7 TeV

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    The Lambda(b) differential production cross section and the cross section ratio anti-Lambda(b)/Lambda(b) are measured as functions of transverse momentum pt(Lambda(b)) and rapidity abs(y(Lambda(b))) in pp collisions at sqrt(s) = 7 TeV using data collected by the CMS experiment at the LHC. The measurements are based on Lambda(b) decays reconstructed in the exclusive final state J/Psi Lambda, with the subsequent decays J/Psi to an opposite-sign muon pair and Lambda to proton pion, using a data sample corresponding to an integrated luminosity of 1.9 inverse femtobarns. The product of the cross section times the branching ratio for Lambda(b) to J/Psi Lambda versus pt(Lambda(b)) falls faster than that of b mesons. The measured value of the cross section times the branching ratio for pt(Lambda(b)) > 10 GeV and abs(y(Lambda(b))) < 2.0 is 1.06 +/- 0.06 +/- 0.12 nb, and the integrated cross section ratio for anti-Lambda(b)/Lambda(b) is 1.02 +/- 0.07 +/- 0.09, where the uncertainties are statistical and systematic, respectively.Comment: Submitted to Physics Letters

    Search for new physics in events with opposite-sign leptons, jets, and missing transverse energy in pp collisions at sqrt(s) = 7 TeV

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    A search is presented for physics beyond the standard model (BSM) in final states with a pair of opposite-sign isolated leptons accompanied by jets and missing transverse energy. The search uses LHC data recorded at a center-of-mass energy sqrt(s) = 7 TeV with the CMS detector, corresponding to an integrated luminosity of approximately 5 inverse femtobarns. Two complementary search strategies are employed. The first probes models with a specific dilepton production mechanism that leads to a characteristic kinematic edge in the dilepton mass distribution. The second strategy probes models of dilepton production with heavy, colored objects that decay to final states including invisible particles, leading to very large hadronic activity and missing transverse energy. No evidence for an event yield in excess of the standard model expectations is found. Upper limits on the BSM contributions to the signal regions are deduced from the results, which are used to exclude a region of the parameter space of the constrained minimal supersymmetric extension of the standard model. Additional information related to detector efficiencies and response is provided to allow testing specific models of BSM physics not considered in this paper.Comment: Replaced with published version. Added journal reference and DO
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