454 research outputs found
Virtual Effects of Split SUSY in Higgs Productions at Linear Colliders
In split supersymmetry the gauginos and higgsinos are the only supersymmetric
particles possibly accessible at foreseeable colliders like the CERN Large
Hadron Collider (LHC) and the International Linear Collider (ILC). In order to
account for the cosmic dark matter measured by WMAP, these gauginos and
higgsinos are stringently constrained and could be explored at the colliders
through their direct productions and/or virtual effects in some processes. The
clean environment and high luminosity of the ILC render the virtual effects of
percent level meaningful in unraveling the new physics effects. In this work we
assume split supersymmetry and calculate the virtual effects of the
WMAP-allowed gauginos and higgsinos in Higgs productions e+e- -> Z h and e+e-
-> \nu_e \bar_\nu_e h through WW fusion at the ILC. We find that the production
cross section of e+e- -> Zh can be altered by a few percent in some part of the
WMAP-allowed parameter space, while the correction to the WW-fusion process
e+e- -> \nu_e \bar_\nu_e h is below 1%. Such virtual effects are correlated
with the cross sections of chargino pair productions and can offer
complementary information in probing split supersymmetry at the colliders.Comment: more discussions added (7 pages, 10 figs
The global epidemiology of hepatitis E virus infection: A systematic review and meta-analysis
Background and aims: Hepatitis E virus (HEV), as an emerging zoonotic pathogen, is a leading cause of acute viral hepatitis worldwide, with a high risk of developing chronic infection in immunocompromised patients. However, the global epidemiology of HEV infection has not been comprehensively assessed. This study aims to map the global prevalence and identify the risk factors of HEV infection by performing a systematic review and meta-analysis. Methods: A systematic searching of articles published in Medline, Embase, Web of science, Cochrane and Google scholar databases till July 2019 was conducted to identify studies with HEV prevalence data. Pooled prevalence among different countries and continents was estimated. HEV IgG seroprevalence of subgroups was compared and risk factors for HEV infection were evaluated using odd ratios (OR). Results: We identified 419 related studies which comprised of 1Â 519Â 872 individuals. A total of 1Â 099Â 717 participants pooled from 287 studies of general population estimated a global anti-HEV IgG seroprevalence of 12.47% (95% CI 10.42-14.67; I2Â =Â 100%). Notably, the use of ELISA kits from different manufacturers has a substantial impact on the global estimation of anti-HEV IgG seroprevalence. The pooled estimate of anti-HEV IgM seroprevalence based on 98 studies is 1.47% (95% CI 1.14-1.85; I2Â =Â 99%). The overall estimate of HEV viral RNA-positive rate in general population is 0.20% (95% CI 0.15-0.25; I2Â =Â 98%). Consumption of raw meat (PÂ =.0001), exposure to soil (PÂ <.0001), blood transfusion (PÂ =.0138), travelling to endemic areas (PÂ =.0244), contacting with dogs (PÂ =.0416), living in rural areas (PÂ =.0349) and receiving education less than elementary school (PÂ <.0001) were identified as risk factors for anti-HEV IgG positivity. Conclusions: Globally, approximately 939Â million corresponding to 1 in 8 individuals have ever experienced HEV infection. 15-110Â million individuals have recent or ongoing HEV infection. Our study highlights the substantial burden of HEV infection and calls for increasing routine screening and preventive measures
Non-Markovian dynamics in a spin star system: The failure of thermalization
In most cases, a small system weakly interacting with a thermal bath will
finally reach the thermal state with the temperature of the bath. We show that
this intuitive picture is not always true by a spin star model where non-Markov
effect predominates in the whole dynamical process. The spin star system
consists a central spin homogeneously interacting with an ensemble of identical
noninteracting spins. We find that the correlation time of the bath is
infinite, which implies that the bath has a perfect memory, and that the
dynamical evolution of the central spin must be non- Markovian. A direct
consequence is that the final state of the central spin is not the thermal
state equilibrium with the bath, but a steady state which depends on its
initial state.Comment: 8 page
Direct-acting antiviral agents for liver transplant recipients with recurrent genotype 1 hepatitis C virus infection: Systematic review and meta-analysis
Background: Comprehensive evaluation of safety and efficacy of different combinaâ
tions of directâacting antivirals (DAAs) in liver transplant recipients with genotype 1
(GT1) hepatitis C virus (HCV) recurrence remains limited. Therefore, we performed
this systematic review and metaâanalysis in order to evaluate the clinical outcome of
DAA treatment in liver transplant patients with HCV GT1 recurrence.
Methods: Studies were included if they contained information of 12 weeks sustained
virologic response (SVR12) after DAA treatment completion as well as treatment reâ
lated complications for liver transplant recipients with GT1 HCV recurrence.
Results: We identified 16 studies comprising 885 patients. The overall pooled estiâ
mate proportion of SVR12 was 93% (95% confidence interval (CI): 0.89, 0.96), with
moderate heterogeneity observed (Ï
2 = 0.01, P < 0.01, I
2
=75%). High tolerability was
observed in liver transplant recipients reflected by serious adverse events (sAEs) with
pooled estimate proportion of 4% (95% CI: 0.01, 0.07; Ï2 = 0.02, P < 0.01, I
2 = 81%).
For subgroup analysis, a total of five different DAA regimens were applied for treating
these patients. Sofosbuvir/Ledipasvir (SOF/LDV) led the highest pooled estimate
SVR12 proportion, followed by Paritaprevir/Ritonavir/Ombitasivir/Dasabuvir (PrOD),
Daclatasvir (DCV)/Simeprevir (SMV) ± Ribavirin (RBV), and SOF/SMV ± RBV,
Asunaprevir (ASV)/DCV. There was a tendency for favoring a higher pooled SVR12
proportion in patients with METAVIR Stage F0âF2 of 97% (95% CI: 0.93, 0.99) comâ
pared to 85% (95% CI: 0.79, 0.90) for stage F3âF4 (P < 0.01). There was no significant
difference between LT recipients treated with or without RBV (P = 0.23).
Conclusions: Directâacting antiviral treatment is highly effective and wellâtolerated
in liver transplant recipients with recurrent GT1 HCV infection
CETSA-based target engagement of taxanes as biomarkers for efficacy and resistance
The use of taxanes has for decades been crucial for treatment of several cancers. A major limitation of these therapies is inherent or acquired drug resistance. A key to improved outcome of taxane-based therapies is to develop tools to predict and monitor drug efficacy and resistance in the clinical setting allowing for treatment and dose stratification for individual patients. To assess treatment efficacy up to the level of drug target engagement, we have established several formats of tubulin-specific Cellular Thermal Shift Assays (CETSAs). This technique was evaluated in breast and prostate cancer models and in a cohort of breast cancer patients. Here we show that taxanes induce significant CETSA shifts in cell lines as well as in animal models including patient-derived xenograft (PDX) models. Furthermore, isothermal dose response CETSA measurements allowed for drugs to be rapidly ranked according to their reported potency. Using multidrug resistant cancer cell lines and taxane-resistant PDX models we demonstrate that CETSA can identify taxane resistance up to the level of target engagement. An imaging-based CETSA format was also established, which in principle allows for taxane target engagement to be accessed in specific cell types in complex cell mixtures. Using a highly sensitive implementation of CETSA, we measured target engagement in fine needle aspirates from breast cancer patients, revealing a range of different sensitivities. Together, our data support that CETSA is a robust tool for assessing taxane target engagement in preclinical models and clinical material and therefore should be evaluated as a prognostic tool during taxane-based therapies
Lepton flavor violation decays in the topcolor-assisted technicolor model and the littlest Higgs model with parity
The new particles predicted by the topcolor-assisted technicolor ()
model and the littlest Higgs model with T-parity (called model) can
induce the lepton flavor violation () couplings at tree level or one loop
level, which might generate large contributions to some processes. Taking
into account the constraints of the experimental data on the relevant free
parameters, we calculate the branching ratios of the decay processes
with = , and
in the context of these two kinds of new physics models. We find
that the model and the model can indeed produce significant
contributions to some of these decay processes.Comment: 24 pages, 7 figure
Recommendations for Epstein-Barr virusâbased screening for nasopharyngeal cancer in high- and intermediate-risk regions
A meeting of experts was held in November 2021 to review and discuss available data on performance of Epstein-Barr virus (EBV)âbased approaches to screen for early stage nasopharyngeal carcinoma (NPC) and methods for the investigation and management of screen-positive individuals. Serum EBV antibody and plasma EBV DNA testing methods were considered. Both approaches were found to have favorable performance characteristics and to be cost-effective in high-risk populations. In addition to endoscopy, use of magnetic resonance imaging (MRI) to investigate screen-positive individuals was found to increase the sensitivity of NPC detection with minimal impact on cost-effectiveness of the screening program
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