72 research outputs found

    Le Chatelier-Braun principle in cosmological physics

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    Assuming that dark energy may be treated as a fluid with a well defined temperature, close to equilibrium, we argue that if nowadays there is a transfer of energy between dark energy and dark matter, it must be such that the latter gains energy from the former and not the other way around.Comment: 6 pages, revtex file, no figures; version accepted for publication in General Relativity and Gravitatio

    Cosmic coincidence problem and variable constants of physics

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    The standard model of cosmology is investigated using time dependent cosmological constant Λ\Lambda and Newton's gravitational constant GG. The total energy content is described by the modified Chaplygin gas equation of state. It is found that the time dependent constants coupled with the modified Chaplygin gas interpolate between the earlier matter to the later dark energy dominated phase of the universe. We also achieve a convergence of parameter ω→−1\omega\to-1, with minute fluctuations, showing an evolving ω\omega. Thus our model fairly alleviates the cosmic coincidence problem which demands ω=−1\omega=-1 at present time.Comment: 27 pages, 15 figure

    Phase space analysis of interacting dark energy in f(T) cosmology

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    In this paper, we examine the interacting dark energy model in f(T)f(T) cosmology. We assume dark energy as a perfect fluid and choose a specific cosmologically viable form f(T)=ÎČTf(T)= \beta\sqrt{T} . We show that there is one attractor solution to the dynamical equation of f(T)f(T) Friedmann equations. Further we investigate the stability in phase space for a general f(T)f(T) model with two interacting fluids. By studying the local stability near the critical points, we show that the critical points lie on the sheet u∗=(c−1)v∗u^*=(c-1)v^* in the phase space, spanned by coordinates (u,v,Ω,T)(u,v,\Omega,T). From this critical sheet, we conclude that the coupling between the dark energy and matter c∈(−2,0)c\in (-2,0).Comment: 13 pages,2 figures, Published in "Central European Journal of Physics

    Evolution of the use of corticosteroids for the treatment of hospitalised COVID-19 patients in Spain between March and November 2020: SEMI-COVID national registry

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    Objectives: Since the results of the RECOVERY trial, WHO recommendations about the use of corticosteroids (CTs) in COVID-19 have changed. The aim of the study is to analyse the evolutive use of CTs in Spain during the pandemic to assess the potential influence of new recommendations. Material and methods: A retrospective, descriptive, and observational study was conducted on adults hospitalised due to COVID-19 in Spain who were included in the SEMI-COVID- 19 Registry from March to November 2020. Results: CTs were used in 6053 (36.21%) of the included patients. The patients were older (mean (SD)) (69.6 (14.6) vs. 66.0 (16.8) years; p < 0.001), with hypertension (57.0% vs. 47.7%; p < 0.001), obesity (26.4% vs. 19.3%; p < 0.0001), and multimorbidity prevalence (20.6% vs. 16.1%; p < 0.001). These patients had higher values (mean (95% CI)) of C-reactive protein (CRP) (86 (32.7-160) vs. 49.3 (16-109) mg/dL; p < 0.001), ferritin (791 (393-1534) vs. 470 (236- 996) ”g/dL; p < 0.001), D dimer (750 (430-1400) vs. 617 (345-1180) ”g/dL; p < 0.001), and lower Sp02/Fi02 (266 (91.1) vs. 301 (101); p < 0.001). Since June 2020, there was an increment in the use of CTs (March vs. September; p < 0.001). Overall, 20% did not receive steroids, and 40% received less than 200 mg accumulated prednisone equivalent dose (APED). Severe patients are treated with higher doses. The mortality benefit was observed in patients with oxygen saturation </=90%. Conclusions: Patients with greater comorbidity, severity, and inflammatory markers were those treated with CTs. In severe patients, there is a trend towards the use of higher doses. The mortality benefit was observed in patients with oxygen saturation </=90%

    Team dynamics in emergency surgery teams: results from a first international survey

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    Background: Emergency surgery represents a unique context. Trauma teams are often multidisciplinary and need to operate under extreme stress and time constraints, sometimes with no awareness of the trauma\u2019s causes or the patient\u2019s personal and clinical information. In this perspective, the dynamics of how trauma teams function is fundamental to ensuring the best performance and outcomes. Methods: An online survey was conducted among the World Society of Emergency Surgery members in early 2021. 402 fully filled questionnaires on the topics of knowledge translation dynamics and tools, non-technical skills, and difficulties in teamwork were collected. Data were analyzed using the software R, and reported following the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). Results: Findings highlight how several surgeons are still unsure about the meaning and potential of knowledge translation and its mechanisms. Tools like training, clinical guidelines, and non-technical skills are recognized and used in clinical practice. Others, like patients\u2019 and stakeholders\u2019 engagement, are hardly implemented, despite their increasing importance in the modern healthcare scenario. Several difficulties in working as a team are described, including the lack of time, communication, training, trust, and ego. Discussion: Scientific societies should take the lead in offering training and support about the abovementioned topics. Dedicated educational initiatives, practical cases and experiences, workshops and symposia may allow mitigating the difficulties highlighted by the survey\u2019s participants, boosting the performance of emergency teams. Additional investigation of the survey results and its characteristics may lead to more further specific suggestions and potential solutions

    Pain distress : the negative emotion associated with procedures in ICU patients

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    The intensity of procedural pain in intensive care unit (ICU) patients is well documented. However, little is known about procedural pain distress, the psychological response to pain. Post hoc analysis of a multicenter, multinational study of procedural pain. Pain distress was measured before and during procedures (0-10 numeric rating scale). Factors that influenced procedural pain distress were identified by multivariable analyses using a hierarchical model with ICU and country as random effects. A total of 4812 procedures were recorded (3851 patients, 192 ICUs, 28 countries). Pain distress scores were highest for endotracheal suctioning (ETS) and tracheal suctioning, chest tube removal (CTR), and wound drain removal (median [IQRs] = 4 [1.6, 1.7]). Significant relative risks (RR) for a higher degree of pain distress included certain procedures: turning (RR = 1.18), ETS (RR = 1.45), tracheal suctioning (RR = 1.38), CTR (RR = 1.39), wound drain removal (RR = 1.56), and arterial line insertion (RR = 1.41); certain pain behaviors (RR = 1.19-1.28); pre-procedural pain intensity (RR = 1.15); and use of opioids (RR = 1.15-1.22). Patient-related variables that significantly increased the odds of patients having higher procedural pain distress than pain intensity were pre-procedural pain intensity (odds ratio [OR] = 1.05); pre-hospital anxiety (OR = 1.76); receiving pethidine/meperidine (OR = 4.11); or receiving haloperidol (OR = 1.77) prior to the procedure. Procedural pain has both sensory and emotional dimensions. We found that, although procedural pain intensity (the sensory dimension) and distress (the emotional dimension) may closely covary, there are certain factors than can preferentially influence each of the dimensions. Clinicians are encouraged to appreciate the multidimensionality of pain when they perform procedures and use this knowledge to minimize the patient's pain experience.Peer reviewe

    Different prognostic impact of recurrent gene mutations in chronic lymphocytic leukemia depending on IGHV gene somatic hypermutation status: a study by ERIC in HARMONY

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    Recent evidence suggests that the prognostic impact of gene mutations in patients with chronic lymphocytic leukemia (CLL) may differ depending on the immunoglobulin heavy variable (IGHV) gene somatic hypermutation (SHM) status. In this study, we assessed the impact of nine recurrently mutated genes (BIRC3, EGR2, MYD88, NFKBIE, NOTCH1, POT1, SF3B1, TP53, and XPO1) in pre-treatment samples from 4580 patients with CLL, using time-to-first-treatment (TTFT) as the primary end-point in relation to IGHV gene SHM status. Mutations were detected in 1588 (34.7%) patients at frequencies ranging from 2.3-9.8% with mutations in NOTCH1 being the most frequent. In both univariate and multivariate analyses, mutations in all genes except MYD88 were associated with a significantly shorter TTFT. In multivariate analysis of Binet stage A patients, performed separately for IGHV-mutated (M-CLL) and unmutated CLL (U-CLL), a different spectrum of gene alterations independently predicted short TTFT within the two subgroups. While SF3B1 and XPO1 mutations were independent prognostic variables in both U-CLL and M-CLL, TP53, BIRC3 and EGR2 aberrations were significant predictors only in U-CLL, and NOTCH1 and NFKBIE only in M-CLL. Our findings underscore the need for a compartmentalized approach to identify high-risk patients, particularly among M-CLL patients, with potential implications for stratified management
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