41 research outputs found

    Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

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    Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

    Search for dark photons in Higgs boson production via vector boson fusion in proton-proton collisions at √s = 13 TeV

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    A search is presented for a Higgs boson that is produced via vector boson fusion and that decays to an undetected particle and an isolated photon. The search is performed by the CMS collaboration at the LHC, using a data set corresponding to an integrated luminosity of 130 fb−1, recorded at a center-of-mass energy of 13 TeV in 2016–2018. No significant excess of events above the expectation from the standard model background is found. The results are interpreted in the context of a theoretical model in which the undetected particle is a massless dark photon. An upper limit is set on the product of the cross section for production via vector boson fusion and the branching fraction for such a Higgs boson decay, as a function of the Higgs boson mass. For a Higgs boson mass of 125 GeV, assuming the standard model production rates, the observed (expected) 95% confidence level upper limit on the branching fraction is 3.5 (2.8)%. This is the first search for such decays in the vector boson fusion channel. Combination with a previous search for Higgs bosons produced in association with a Z boson results in an observed (expected) upper limit on the branching fraction of 2.9 (2.1)% at 95% confidence level

    4to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica

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    Este volumen acoge la memoria académica de la Cuarta edición del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2017, desarrollado entre el 29 de noviembre y el 1 de diciembre de 2017 y organizado por la Universidad Politécnica Salesiana (UPS) en su sede de Guayaquil. El Congreso ofreció un espacio para la presentación, difusión e intercambio de importantes investigaciones nacionales e internacionales ante la comunidad universitaria que se dio cita en el encuentro. El uso de herramientas tecnológicas para la gestión de los trabajos de investigación como la plataforma Open Conference Systems y la web de presentación del Congreso http://citis.blog.ups.edu.ec/, hicieron de CITIS 2017 un verdadero referente entre los congresos que se desarrollaron en el país. La preocupación de nuestra Universidad, de presentar espacios que ayuden a generar nuevos y mejores cambios en la dimensión humana y social de nuestro entorno, hace que se persiga en cada edición del evento la presentación de trabajos con calidad creciente en cuanto a su producción científica. Quienes estuvimos al frente de la organización, dejamos plasmado en estas memorias académicas el intenso y prolífico trabajo de los días de realización del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad al alcance de todos y todas

    Measurement of the Higgs boson production rate in association with top quarks in final states with electrons, muons, and hadronically decaying tau leptons at s√=13TeV

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    The rate for Higgs (H) bosons production in association with either one (tH) or two (tt¯H) top quarks is measured in final states containing multiple electrons, muons, or tau leptons decaying to hadrons and a neutrino, using proton–proton collisions recorded at a center-of-mass energy of 13TeV by the CMS experiment. The analyzed data correspond to an integrated luminosity of 137fb−1. The analysis is aimed at events that contain H→WW, H→ττ, or H→ZZ decays and each of the top quark(s) decays either to lepton+jets or all-jet channels. Sensitivity to signal is maximized by including ten signatures in the analysis, depending on the lepton multiplicity. The separation among tH, tt¯H, and the backgrounds is enhanced through machine-learning techniques and matrix-element methods. The measured production rates for the tt¯H and tH signals correspond to 0.92±0.19(stat)+0.17−0.13(syst) and 5.7±2.7(stat)±3.0(syst) of their respective standard model (SM) expectations. The corresponding observed (expected) significance amounts to 4.7 (5.2) standard deviations for tt¯H, and to 1.4 (0.3) for tH production. Assuming that the Higgs boson coupling to the tau lepton is equal in strength to its expectation in the SM, the coupling yt of the Higgs boson to the top quark divided by its SM expectation, κt=yt/ySMt, is constrained to be within −0.9<κt<−0.7 or 0.7<κt<1.1, at 95% confidence level. This result is the most sensitive measurement of the tt¯H production rate to date.SCOAP

    Miología pectoral de algunos centrolenidae (Amphibia: anura)

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    El estudio comparativo de la miología pectoral en dos géneros de Centrolenidae (Centrolene e Hyalinobatrachium) que incluyen a cuatro especies (C. geckoideum, C. grandisonae, C. robledal y H. aureoguttatum), brinda una visión más completa de la morfología de la cintura pectoral en los anuros, ampliando la información disponible. Este estudio incorpora caracteres nuevos para el tratado de la familia, antecedente de importancia ya que los caracteres frecuentemente utilizados para definir al grupo son homoplásicos (Lynch, 1973; Duellman & Trueb, 1986; Ford & Cannatella, 1993) y ponen en duda la monofilia del grupo. Los resultados muestran la escasa variabilidad de la musculatura pectoral en los géneros de Centrolenidae. Al mismo tiempo resaltan variaciones con el género Hyalinobatrachium en relación con los músculos depressor mandibulae y pectoralis abdominalis. En general existe una tendencia a la duplicación de algunos músculos como el serratus inferioris, dorsal scapulae y depressor mandibulae (característica observada también en Hylidae; Manzano, 1996).Asociación Herpetológica Argentin

    Miología pectoral de algunos centrolenidae (Amphibia: anura)

    No full text
    El estudio comparativo de la miología pectoral en dos géneros de Centrolenidae (Centrolene e Hyalinobatrachium) que incluyen a cuatro especies (C. geckoideum, C. grandisonae, C. robledal y H. aureoguttatum), brinda una visión más completa de la morfología de la cintura pectoral en los anuros, ampliando la información disponible. Este estudio incorpora caracteres nuevos para el tratado de la familia, antecedente de importancia ya que los caracteres frecuentemente utilizados para definir al grupo son homoplásicos (Lynch, 1973; Duellman & Trueb, 1986; Ford & Cannatella, 1993) y ponen en duda la monofilia del grupo. Los resultados muestran la escasa variabilidad de la musculatura pectoral en los géneros de Centrolenidae. Al mismo tiempo resaltan variaciones con el género Hyalinobatrachium en relación con los músculos depressor mandibulae y pectoralis abdominalis. En general existe una tendencia a la duplicación de algunos músculos como el serratus inferioris, dorsal scapulae y depressor mandibulae (característica observada también en Hylidae; Manzano, 1996).Asociación Herpetológica Argentin

    Morphology and function of the forelimb in arboreal frogs: specializations for grasping ability? Journal of Anatomy 213:296–307

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    Abstract Frogs are characterized by a unique morphology associated with their saltatory lifestyle. Although variation in the form and function of the pelvic girdle and associated appendicular system related to specialized locomotor modes such as swimming or burrowing has been documented, the forelimbs have typically been viewed as relatively unspecialized. Yet, previous authors have noted versatility in forelimb function among arboreal frogs associated with feeding. Here we study the morphology and function of the forelimb and hand during locomotion in two species of arboreal frogs ( Litoria caerulea and Phyllomedusa bicolor ). Our data show a complex arrangement of the distal forelimb and hand musculature with some notable differences between species. Analyses of high-speed video and video fluoroscopy recordings show that forelimbs are used in alternating fashion in a diagonal sequence footfall pattern and that the position of the hand is adjusted when walking on substrates of different diameters. Electromyographic recordings show that the flexors of the hand are active during substrate contact, suggesting the use of gripping to generate a stabilizing torque. Measurements of grasping forces in vivo and during stimulation experiments show that both species, are capable of executing a so-called power grip but also indicates marked differences between species, in the magnitude of forces generated. Stimulation experiments showed an increased control of digit flexion in the more specialized of the two species, allowing it to execute a precision grip paralleled only by that seen in primates

    The distal forelimb musculature in aquatic and terrestrial turtles: phylogeny or environmental constraints?

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    We compared the muscular anatomy of the distal front limb in terrestrial and aquatic chelonians to test whether observed differences between the two groups are associated with their divergent lifestyles and locomotor modes. Given the different use of the forelimb in the two environments (body support and propulsion on land vs. mainly propulsion in water) we expected that: (1) aquatic and terrestrial turtles would show differences in their muscular anatomy, with aquatic species having more individualized muscle bundles to allow for the complex forearm movements observed during swimming, and (2) that terrestrial turtles would have more robust muscles to support their body weight against gravity. To address these questions, we examined the forelimb myology and associated tissues in six aquatic or semi-aquatic turtles (Phyrnops hilarii, Podocnemis unifilis, Trachemys scripta, Sacalia bealei, Cuora amboinensis and Mauremys caspica) and six terrestrial or semi-terrestrial turtles (Geochelone chilensis, Testudo graeca, Cuora galbinifrons, Glyptemys insculpta, Terrapene carolina and Rhinoclemmys pulcherrima). This paper describes the general structure of the forelimb musculature in all species, and quantifies muscle masses in those species with more than five specimens available (Ph. hilarii, Po. unifilis and Ge. chilensis). The general structure of the forelimb muscles in the strictly terrestrial species Ge. chilensis and Tes. graeca was found to be notably different from the pattern of the aquatic and semi-aquatic species examined, showing a distinct fusion of the different muscular bodies. Ter. carolina also show a distinctly terrestrial pattern, but a less extensive tendon development. R. pulcherrima and Gl. insculpta were found to be morphologically intermediate; in the geoemydids the strictly terrestrial bauplan never appears. Quantitative differences in the robustness or mass of the distal forelimb muscles were also observed for the species investigated, supporting our prediction that the extensor muscles are more robust in terrestrial turtles. However, in contrast to our expectations, not only the extensor muscles of the distal forelimb (which are crucial in providing both body support and propulsion), but all muscles acting around the wrist were found to be heavier in terrestrial turtles

    CoCrMo alloy as biomaterial for bone reconstruction in oral and maxillofacial surgery: A scoping review

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    Background: Osseointegration allowed for a breakthrough in biomaterials and techniques and it has contributed to increased application of dental implants. However, insufficient bone level is a frequent problem and it creates an anatomically less favourable base for implant placement. The first surgical procedure should comprise the reconstruction of the alveolar bone height. CoCrMo alloys are nowadays considered as highly corrosion resistant and biocompatible materials in dentistry, and therefore has been suggested as a suitable biomaterial for guided bone regeneration and tissue engineering. Aim: To determine the use of CoCrMo alloy for implantable devices in oral and maxillofacial surgery and to discuss the potential of this alloy for bone regeneration and repair through a scoping review. Material and methods: The search was done by using various databases including PubMed, Thomson Reuters and Scopus. We selected English literature related to studies reporting the CoCrMo properties and manufacturing processes and findings related to bone-forming techniques. Data was compared qualitatively. Results: 90 studies were selected according to the inclusion criteria. We reported different manufacturing techniques and their advantages related to mechanical, chemical and biocompatible properties. Conclusion: Improved tissue reactions of CoCrMo implant devices can be acquired by the application of novel techniques and surface modifications. Moreover, several processes have demonstrated to improve the in vitro and in vivo biocompatibility of the CoCrMo alloy to promote the attachment, proliferation and guided differentiation of seeding cells.Antecedentes: La osteointegración ha permitido un gran avance en biomateriales y técnicas, y ha contribuido un mayor uso de implantes dentales. Sin embargo, la existencia de un nivel óseo insuficiente es un problema frecuente y crea una base anatómicamente menos favorable para la colocación de implantes. El primer procedimiento quirúrgico debe comprender la reconstrucción de la altura del hueso alveolar. Las aleaciones de CoCrMo se consideran hoy en día como materiales altamente resistentes a la corrosión y biocompatibles en odontología y, por lo tanto, se ha sugerido como un biomaterial adecuado para la regeneración ósea guiada y la ingeniería de tejidos. Objetivo: Determinar el uso de la aleación CoCrMo para dispositivos implantables en cirugía oral y maxilofacial y discutir sobre el potencial de esta aleación para la regeneración y reparación ósea a través de una revisión de alcance. Material y Métodos: La búsqueda se realizó utilizando varias bases de datos, incluidas PubMed, Thomson Reuters y Scopus. Se seleccionó literatura inglesa relacionada con estudios que informan sobre las propiedades de CoCrMo y los procesos de fabricación y los hallazgos relacionados con las técnicas de formación de huesos. Los datos se compararon cualitativamente. Resultados: Se seleccionaron 90 estudios según los criterios de inclusión. y se reportaron diferentes técnicas de fabricación y sus ventajas relacionadas con propiedades mecánicas, químicas y biocompatibles. Conclusión: Las reacciones tisulares mejoradas de los dispositivos de implante CoCrMo pueden adquirirse mediante la aplicación de nuevas técnicas y modificaciones de la superficie. Además, varios procesos han demostrado mejorar la biocompatibilidad in vitro e in vivo de la aleación CoCrMo para promover la unión, proliferación y diferenciación guiada de las células de siembra

    First evidence of the effects of agricultural activities on gonadal form and function in Rhinella fernandezae and Dendropsophus sanborni (Amphibia: Anura) from Entre Ríos Province, Argentina

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    The relationship between male gonadal abnormalities and habitats with different degrees of agricultural activities was quantified in two anuran species, Rhinella fernandezae and Dendropsophus sanborni. The study sites were selected along a gradient of increasing agricultural land use in south-western Entre Ríos province (Argentina): an agroecosystem, a natural wetland (a non-agricultural site adjacent to monoculture zones), and a natural forest (not associated with agriculture). Rhinella fernandezae and D. sanborni were manually captured from each environment during field surveys. A scaled mass index (MI) was evaluated for each animal. Specimens of R. fernandezae from the agroecosystem and the natural wetland site presented poorly developed seminiferous tubules, lower testicular volume, and a lower number of seminiferous tubules, primary spermatogonia, and spermatids than specimens from the natural forest site. Additionally, we observed fewer primary spermatocytes in the agroecosystem group than in the natural forest group. Individuals of D. sanborni from the agroecosystem and the natural wetland site presented poorly developed tubules, higher proportions of irregularly shaped testes, and a reduced number of primary and secondary spermatogonia compared with specimens from natural forest sites. Consequently, the affected anurans are likely to have reduced reproductive success. We suggest that agrochemical use may be associated with decreased testicular development and function in both R. fernandezae and D. sanborni occurring in agroecosystems and nearby environments. Buffer zones are needed to prevent contamination, preserve wildlife, and enhance the conservation value of pristine natural forests
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