84 research outputs found

    Fermionic Wigs for BTZ Black Holes

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    We compute the wig for the BTZ black hole, namely the complete non-linear solution of supergravity equations with all fermionic zero modes. We use a "gauge completion" method starting from AdS_3 Killing spinors to generate the gravitinos fields associated to the BH and we compute the back-reaction on the metric. Due to the anticommutative properties of the fermionic hairs the resummation of these effects truncates at some order. We illustrate the technique proposed in a precedent paper in a very explicit and analytical form. We also compute the mass, the angular momentum and other charges with their corrections.Comment: 11 pages, no figure

    Fermionic Corrections to Fluid Dynamics from BTZ Black Hole

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    We reconstruct the complete fermionic orbit of the non-extremal BTZ black hole by acting with finite supersymmetry transformations. The solution satisfies the exact supergravity equations of motion to all orders in the fermonic expansion and the final result is given in terms of fermionic bilinears. By fluid/gravity correspondence, we derive linearized Navier-Stokes equations and a set of new differential equations from Rarita-Schwinger equation. We compute the boundary energy-momentum tensor and we interpret the result as a perfect fluid with a modified definition of fluid velocity. Finally, we derive the modified expression for the entropy of the black hole in terms of the fermionic bilinears.Comment: 21 pages, Latex2e, no figure

    Fermions, Wigs, and Attractors

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    We compute the modifications to the attractor mechanism due to fermionic corrections. In N=2, D=4 supergravity, at the fourth order, we find a new contribution to the horizon values of the scalar fields of the vector multiplets.Comment: v2 : 1+11 pages; paper reorganized in Sections; Sec. 5 added, with detailed treatment of the axion-dilaton model; some typos fixed and references adde

    No Fermionic Wigs for BPS Attractors in 5 Dimensions

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    We analyze the fermionic wigging of 1/2-BPS (electric) extremal black hole attractors in N=2, D=5 ungauged Maxwell-Einstein supergravity theories, by exploiting anti-Killing spinors supersymmetry transformations. Regardless of the specific data of the real special geometry of the manifold defining the scalars of the vector multiplets, and differently from the D=4 case, we find that there are no corrections for the near--horizon attractor value of the scalar fields; an analogous result also holds for 1/2-BPS (magnetic) extremal black string. Thus, the attractor mechanism receives no fermionic corrections in D=5 (at least in the BPS sector).Comment: 24 pages, LaTeX2

    Sex disparities in efficacy in covid-19 vaccines: A systematic review and meta-analysis

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    Sex differences in adaptive and innate immune responses have been shown to occur and anecdotal reports suggest that vaccine efficacy and safety may be sex-dependent. We investigated the influence of sex on the efficacy of COVID-19 vaccines through a systematic review and meta-analysis of clinical trials on COVID-19 vaccines. The safety profile of COVID-19 vaccines was also investigated. A systematic review included eligible articles published in three databases and three websites. A meta-analysis of available data, stratified by sex, was conducted. Statistical analysis was performed using the Hartung\u2013Knapp\u2013Sidik\u2013Jonkman method, as well as influence and heterogeneity analysis. Pooled analysis showed significantly higher efficacy, measured as the rate of new COVID-19 cases, in men compared to women in the vaccine group (OR = 0.67, 95% CI 0.48\u20130.94). No sex differences were found in the rate of new cases in the control group (OR = 0.92, 95% CI 0.78\u20131.09). Safety profiles derived from pharmacovigilance reports appear to indicate increased toxicity in women. In conclusion, evidence of a potential role of sex in COVID-19 vaccine efficacy was described. It strengthens the need to include sex as a core variable in the clinical trial design of COVID-19 vaccines

    New insights into the pharmacological, immunological, and CAR-T-cell approaches in the treatment of hepatocellular carcinoma.

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    The tyrosine kinase inhibitor (TKI) sorafenib continues to be the anchor drug in the treatment of advanced stage hepatocellular carcinoma (HCC). Other TKIs as well as immune checkpoint inhibitors (ICIs) have also been approved, however the response rates remain poor and heterogeneous among HCC patients, largely due to antitumor drug resistance. Studies aimed at identifying novel biomarkers and developing new strategies to improve the response to current treatment and to overcome drug resistance, are urgently needed. Germline or somatic mutations, neoantigens, and an immunotolerogenic state against constant inflammatory stimuli in the liver, are crucial for the anti-tumor response. A pharmacogenetic approach has been attempted considering germline polymorphisms in genes encoding for proteins involved in drug-targeted pathways. Single gene and comprehensive multi-gene somatic profiling approaches have been adopted in HCC to identify tumor sensitivity scores and immunogenic profiles that can be exploited for new biomarkers and innovative therapeutic approaches. However, the high genomic heterogeneity of tumors and lack of molecularly targeted agents, hamper the discovery of specific molecular markers of resistance to therapy. Adoptive cell therapy with chimeric antigen receptor redirected T (CAR-T) cells targeting specific tumor-associated antigens (TAAs) was proposed recently. The specificity of the chosen TAA, an efficient homing of CAR-T cells to the tumor site, and the ability of CAR-T cells to survive in the tumor microenvironment are central factors in the success of CAR-T therapy. The current review describes the principal systemic treatments for HCC and the molecular evidence regarding potential predictive host and somatic genetic markers, as well as the emerging strategy of liquid biopsy for disease monitoring. Novel immunotherapeutic approaches for HCC treatment, including the use of ICIs and CAR-T, as well as strategies to overcome drug resistance, are discussed

    Diet switching by mammalian herbivores in response to exotic grass invasion.

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    Invasion by exotic grasses is a severe threat to the integrity of grassland ecosystems all over the world. Because grasslands are typically grazed by livestock and wildlife, the invasion is a community process modulated by herbivory. We hypothesized that the invasion of native South American grasslands by Eragrostis plana Nees, an exotic tussock-forming grass from Africa, could be deterred by grazing if grazers switched dietary preferences and included the invasive grass as a large proportion of their diets

    Protective continuous ventilation strategy during cardiopulmonary bypass in children undergoing surgery for congenital heart disease: a prospective study

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    OBJECTIVES: The aim of this study was to evaluate if a 'protective' (low-tidal/low-frequency) ventilation strategy can shorten the postoperative ventilation time and minimize acute lung injury in children with congenital heart disease (CHD) undergoing repair with cardiopulmonary bypass (CPB). METHODS: This is a single-centre prospective, interventional study, including children with CHD under the age of 5 years, undergoing open-heart surgery with a CPB >60 min, in hypothermia, haemodynamically stable, and without evident genetic abnormalities. Assist-control ventilation (tidal volume of 4 ml/kg, 10 breaths/min, positive end-expiratory pressure 5 cmH2O and FiO2 0.21) was applied in a cohort of patients during CPB. We compared clinical outcomes and in fully ventilated versus non-ventilated (control) patients. Propensity score was used to weigh ventilated and control groups to correct for the effect of other confounding clinical variables. Clinical and ventilation parameters and lung inflammatory biomarkers in tracheal aspirates were measured. The primary outcome was the postoperative intubation time of more or less than 48 h. RESULTS: We included 140 children (53 ventilated, 87 non-ventilated) with different CHD. There were no deaths or adverse events in ventilated patients. Using a weighted generalized linear model, we found no sufficient evidence for an effect of intraoperative ventilation on postoperative intubation time [estimate 0.13 (95% confidence interval, -0.08; 0.35), P = 0.22]. CONCLUSIONS: Continuous low-tidal/low-frequency mechanical ventilation during CPB is safe and harmless. However, no significant advantages were found when compared to non-ventilated patients in terms of postoperative ventilation time

    Fermionic Wigs for AdS-Schwarzschild Black Holes

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    We provide the metric, the gravitino fields and the gauge fields to all orders in the fermionic zero modes for D=5 and D=4, N=2 gauged supergravity solutions starting from non-extremal AdS--Schwarzschild black holes. We compute the Brown-York stress--energy tensor on the boundary of AdS_5 / AdS_4 spaces and we discuss some implications of the fermionic corrections to perfect fluid interpretation of the boundary theory. The complete non-linear solution, which we denote as fermionic wig, is achieved by acting with supersymmetry transformations upon the supergravity fields and that expansion naturally truncates at some order in the fermionic zero modes.Comment: 27 pages, Latex2e, no figures, 3 ancillary file
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