2,521 research outputs found

    On the Chaos Bound in Rotating Black Holes

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    We study out-of-time-order correlators (OTOCs) of rotating BTZ black holes using two different approaches: the elastic eikonal gravity approximation, and the Chern-Simons formulations of 3-dimensional gravity. Within both methods the OTOC is given as a sum of two contributions, corresponding to left and right moving modes. The contributions have different Lyapunov exponents, λL±=2πβ11Ω\lambda_L^{\pm}=\frac{2\pi}{\beta}\frac{1}{1\mp \ell \Omega}, where Ω\Omega is the angular velocity and \ell is the AdS radius. Since λL2πβλL+\lambda_L^{-} \leq \frac{2\pi}{\beta} \leq \lambda_L^{+}, there is an apparent contradiction with the chaos bound. We discuss how the result can be made consistent with the chaos bound if one views β±=β(1Ω)\beta_{\pm}=\beta(1\mp \ell \Omega) as the effective inverse temperatures of the left and right moving modes.Comment: 35 pages, 2 figures. v2: references added, typos corrected, and clarifications added to the discussion sectio

    Učinci gama-zračenja na folikule jajnika

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    In order to observe the morphological and endocrinological changes of the rat and mouse ovarian follicles by gamma-radiation, rats were whole-body irradiated with doses of 3.2 Gy and 8.0 Gy and mice with 2.9 Gy and 7.2 Gy. Sections of ovaria were examined by light microscopy. Concentrations of progesterone, testosterone, and estradiol in ovarian homogenate were determined by radioimmunoassay techniques. Gamma-radiation resulted in the increased percentage of atretic follicles in the groups killed on day 0, day 4, and day 8 after irradiation. The decrease in granulosa cell viability was found in animals killed on day 4 after irradiation. The finding of the high ratio of testosterone to estradiol compared to that of progesterone to testosterone suggests that aromatase activity — steroid biosynthesis from testosterone to estradiol — in granulosa cell could be affected by gamma-radiation.U radu su procjenjivane strukture i endokrinološke promjene u folikulima jajnika štakorica i mišica izazvane gama-zračenjem. Štakorice su bile izložene zračenju od 3,2 Gy ili 8,0 Gy, a mišice od 2,9 Gy ili 7,2 Gy. Životinje su usmrćene dana 0, dana 4, odnosno dana 8 nakon ozračenja. Rezovi debljine 7 µm pripremljeni su za mikroskopiranje. Koncentracije progesterona, testosterona i estradiola u homogenatu jajnika određene su specifičnim radioimunoesejem. Gama-zračenje uzrokovalo je povećanje broja atretičnih folikula u obje skupine životinja usmrćenih 4 odnosno 8 dana nakon ozračivanja. Gama-zračenje također je smanjilo životni vijek granuloza stanica u skupinama usmrćenim 4. dan nakon ozračivanja. Utvrđeno povećanje omjera testosterona prema estradiolu u usporedbi s omjerom progesterona prema testosteronu upućuje na to da gama-zračenje utječe na aktivnost aromataze u steroidnoj biosintezi testosterona u estradiol u granuloza stanicama

    CCN1 Secretion Induced by Cigarette Smoking Extracts Augments IL-8 Release from Bronchial Epithelial Cells

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    Inflammation involves in many cigarette smoke (CS) related diseases including the chronic obstructive pulmonary disease (COPD). Lung epithelial cell released IL-8 plays a crucial role in CS induced lung inflammation. CS and cigarette smoke extracts (CSE) both induce IL-8 secretion and subsequently, IL-8 recruits inflammatory cells into the lung parenchyma. However, the molecular and cellular mechanisms by which CSE triggers IL-8 release remain not completely understood. In this study, we identified a novel extracellular matrix (ECM) molecule, CCN1, which mediated CSE induced IL-8 secretion by lung epithelial cells. We first found that CS and CSE up-regulated CCN1 expression and secretion in lung epithelial cells in vivo and in vitro. CSE up-regulated CCN1 via induction of reactive oxygen spices (ROS) and endoplasmic reticulum (ER) stress. p38 MAPK and JNK activation were also found to mediate the signal pathways in CSE induced CCN1. CCN1 was secreted into ECM via Golgi and membrane channel receptor aquaporin4. After CSE exposure, elevated ECM CCN1 functioned via an autocrine or paracrine manner. Importantly, CCN1 activated Wnt pathway receptor LRP6, subsequently stimulated Wnt pathway component Dvl2 and triggered beta-catenin translocation from cell membrane to cytosol and nucleus. Treatment of Wnt pathway inhibitor suppressed CCN1 induced IL-8 secretion from lung epithelial cells. Taken together, CSE increased CCN1 expression and secretion in lung epithelial cells via induction of ROS and ER stress. Increased ECM CCN1 resulted in augmented IL-8 release through the activation of Wnt pathway

    Massive transfusion protocol: the reason it is necessary

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    Objective. The purpose of this study is to identify problems of emergency transfusion at the bedside and to determine need for massive transfusion protocol. Methods. We included patients who met the criteria for “trauma team activation” and were admitted to division of trauma. The amount of blood product transfused in each unit was investigated for balanced transfusion. We also investigated the compliance with assessment of blood consumption score. The correlation between the time elapsed from patient visit to first transfusion order and time elapsed from first transfusion order to transfusion start was analyzed. Finally, we investigated various factors which serve to influence the decision-making process regarding early transfusion order. Results. Ratio of packed Red blood cells (pRBC): Fresh frozen plasma (FFP) was well-balanced, but platelet transfusion done was much lower than pRBC and FFP in emergency room. The application of emergency blood release did not match the criteria of assessment of blood consumption (ABC) score. The time from the first transfusion order to the transfusion start was found to be constant irrespective of time from patient visit to first transfusion order. And, the time from the first transfusion order to transfusion start did not differ significantly among patients with early transfusion order and delayed transfusion order. Only systolic blood pressure of < 90 mmHg was identified as a major predictor for early transfusion order. Conclusion. Balanced transfusion is not easy and emergency transfusion could be delayed at the bedside. Integrated and systematic structures for massive transfusion protocol would be invaluable and indispensable

    Could Fractional Exhaled Nitric Oxide Test be Useful in Predicting Inhaled Corticosteroid Responsiveness in Chronic Cough? A Systematic Review

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    © 2016 Background Fractional exhaled nitric oxide (FENO) is a safe and convenient test for assessing T H 2 airway inflammation, which is potentially useful in the management of patients with chronic cough. Objective To summarize the current evidence on the diagnostic usefulness of FENO for predicting inhaled corticosteroid (ICS) responsiveness in patients with chronic cough. Methods A systematic literature review was conducted to identify articles published in peer-reviewed journals up to February 2015, without language restriction. We included studies that reported the usefulness of FENO (index test) for predicting ICS responsiveness (reference standard) in patients with chronic cough (target condition). The data were extracted to construct a 2 × 2 accuracy table. Study quality was assessed with Quality Assessment of Diagnostic Accuracy Studies 2. Results We identified 5 original studies (2 prospective and 3 retrospective studies). We identified considerable heterogeneities in study design and outcome definitions, and thus were unable to perform a meta-analysis. The proportion of ICS responders ranged from 44% to 59%. Sensitivity and specificity ranged from 53% to 90%, and from 63% to 97%, respectively. The reported area under the curve ranged from abou t 0.60 to 0.87; however, studies with a prospective design and a lower prevalence of asthma had lower area under the curve values. None measured placebo effects or objective cough frequency. Conclusions We did not find strong evidence to support the use of FENO tests for predicting ICS responsiveness in chronic cough. Further studies need to have a randomized, placebo-controlled design, and should use validated measurement tools for cough. Standardization would facilitate the development of clinical evidence
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