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The superconductivity of a kagome superconductor CsV_{3}Sb_{5} is studied by scanning tunneling microscopy and spectroscopy at ultralow temperature with high resolution. Two kinds of superconducting gaps with multiple sets of coherent peaks and residual zero-energy density of states (DOS) are observed on both half-Cs and Sb surfaces, implying multiband superconductivity. In addition, in-gap states can be induced by magnetic impurities but not by nonmagnetic impurities, suggesting a sign-preserving or s-wave superconducting order parameter. Moreover, the interplay between charge density waves (CDW) and superconductivity differs on various bands, resulting in different density-of-states distributions. Our results suggest that the superconducting gap is likely isotropic on the sections of Fermi surface that play little roles in CDW, and the superconducting gaps on the sections of Fermi surface with anisotropic CDW gaps are likely anisotropic as well. The residual spectral weights at zero energy are attributed to the extremely small superconducting gap on the tiny oval Fermi pockets. Our study provides critical clues for further understanding the superconductivity and its relation to CDW in CsV_{3}Sb_{5}.
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Exotic quantum states arise from the interplay of various degrees of freedom such as charge, spin, orbital, and lattice. Recently, a short-ranged charge order (CO) was discovered deep inside the antiferromagnetic phase of Kagome magnet FeGe, exhibiting close relationships with magnetism. Despite extensive investigations, the CO mechanism remains controversial, mainly because the short-ranged behavior hinders precise identification of CO superstructure. Here, combining multiple experimental techniques, we report the observation of a long-ranged CO in high-quality FeGe samples, which is accompanied with a first-order structural transition. With these high-quality samples, the distorted 2 × 2 × 2 CO superstructure is characterized by a strong dimerization along the c-axis of 1/4 of Ge1-sites in Fe3Ge layers, and in response to that, the 2 × 2 in-plane charge modulations are induced. Moreover, we show that the previously reported short-ranged CO might be related to large occupational disorders at Ge1-site, which upsets the equilibrium of the CO state and the ideal 1 × 1 × 1 structure with very close energies, inducing nanoscale coexistence of these two phases. Our study provides important clues for further understanding the CO properties in FeGe and helps to identify the CO mechanism.
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BACKGROUND/AIMS: Cholestatic liver diseases including primary biliary cholangitis (PBC) are associated with active hepatic fibrogenesis, which ultimately progresses to cirrhosis. Activated hepatic stellate cells (HSCs) are the main fibrogenic effectors in response to cholangiocyte damage. JCAD regulates cell proliferation and malignant transformation in nonalcoholic steatoheaptitis-associated hepatocellular carcinoma (NASH-HCC). However, its participation in cholestatic fibrosis has not been explored yet. METHODS: Serial sections of liver tissue of PBC patients were stained with immunofluorescence. Hepatic fibrosis was induced by bile duct ligation (BDL) in wild-type (WT), global JCAD knockout mice (JCAD-KO) and HSC-specific JCAD knockout mice (HSC-JCAD-KO), and evaluated by histopathology and biochemical tests. In situ-activated HSCs isolated from BDL mice were used to determine effects of JCAD on HSC activation. RESULTS: In consistence with staining of liver sections from PBC patients, immunofluorescent staining revealed that JCAD expression was identified in smooth muscle α-actin (α-SMA)-positive fibroblast-like cells and was significantly up-regulated in WT mice with BDL. JCAD deficiency remarkably ameliorated BDL-induced hepatic injury and fibrosis, as documented by liver hydroxyproline content, when compared to WT mice with BDL. Histopathologically, collagen deposition was dramatically reduced in both JCAD-KO and HSC-JCAD-KO mice compared to WT mice, as visualized by Trichrome staining and semi-quantitative scores. Moreover, JCAD deprivation significantly attenuated in situ HSC activation and reduced expression of fibrotic genes after BDL. CONCLUSION: JCAD deficiency effectively suppressed hepatic fibrosis induced by BDL in mice, and the underlying mechanisms are largely through suppressed Hippo-YAP signaling activity in HSCs.
Subject(s)
Carcinoma, Hepatocellular , Cell Adhesion Molecules , Cholestasis , Liver Neoplasms , Animals , Humans , Mice , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cholestasis/complications , Cholestasis/metabolism , Cholestasis/pathology , Hepatic Stellate Cells/metabolism , Liver/pathology , Liver Cirrhosis/etiology , Liver Cirrhosis/metabolism , Liver Neoplasms/pathology , Mice, Knockout , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolismABSTRACT
Intertwined spin and charge orders have been widely studied in high-temperature superconductors, since their fluctuations may facilitate electron pairing; however, they are rarely identified in heavily electron-doped iron selenides. Here, using scanning tunneling microscopy, we show that when the superconductivity of (Li0.84Fe0.16OH)Fe1-xSe is suppressed by introducing Fe-site defects, a short-ranged checkerboard charge order emerges, propagating along the Fe-Fe directions with an approximately 2aFe period. It persists throughout the whole phase space tuned by Fe-site defect density, from a defect-pinned local pattern in optimally doped samples to an extended order in samples with lower Tc or non-superconducting. Intriguingly, our simulations indicate that the charge order is likely driven by multiple-Q spin density waves originating from the spin fluctuations observed by inelastic neutron scattering. Our study proves the presence of a competing order in heavily electron-doped iron selenides, and demonstrates the potential of charge order as a tool to detect spin fluctuations.
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[This corrects the article DOI: 10.3389/fpsyg.2020.00247.].
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OBJECTIVE: To investigate the incidence of hepatotoxicity in acquired immunodeficiency syndrome (AIDS) patients on combined anti-retroviral therapy (cART) containing nevirapine (NVP) and to assess the risk factors and its impact on cART. METHODS: 330 AIDS patients from March 2003 to June 2008 at local county were enrolled and a retrospective study using Kaplan-meier survival and Multivariate logistic regression modeling was conducted. RESULTS: 267 out of 330 patients received NVP based cART and 63 cases received EFV-based cART. The deference of prevalences of hepatotoxicity between the two groups is statistically significant (Chi2 = 6.691, P = 0.01). 133 out of 267 (49.8%) patients on NVP based cART had at least one episode of ALT elevation during a median 21 months (interquartile ranges, IQR 6, 37) follow-up time, amounts for 28.5 cases per 100 person-years. Baseline ALT elevation (OR = 14.368, P = 0.017)and HCV co-infection (OR = 3.009, P = 0.000) were risk factors for cART related hepatotoxicity, while greatly increased CD4+ T(CD4) cell count was protective against hepatotoxicity development (OR = 0.996, P = 0.000). Patients co-infected with HCV received NVP-based cART had the higher probability of hepatotoxicity than those without HCV co-infection (Log rank: Chi2 = 16.764, P = 0.000). 23 out of the 133 subjects (17.3%) with NVP related hepatotoxicity discontinued cART temporarily or shifted NVP to efavirenz. CONCLUSION: NVP related hepatotoxicity was common among ARV naive HIV infected subjects in our cohort. Baseline ALT elevation and HCV co-infection were associated statistically with the development of hepatotoxicity. Hepatotoxicity led to discontinuing cART temporarily or switching to other regimens in some subjects. It suggested that NVP should be used with caution in patients co-infected with HCV among whom anti-HCV therapy before cART initiation may contribute to minimizing the probability of NVP associated hepatotoxicity.
Subject(s)
Acquired Immunodeficiency Syndrome/metabolism , Anti-Retroviral Agents/adverse effects , Chemical and Drug Induced Liver Injury/epidemiology , Liver/drug effects , Nevirapine/adverse effects , Acquired Immunodeficiency Syndrome/drug therapy , Adolescent , Adult , Asian People , Chemical and Drug Induced Liver Injury/virology , Female , Humans , Incidence , Liver/metabolism , Male , Middle Aged , Retrospective Studies , Risk Factors , Young AdultABSTRACT
[This corrects the article DOI: 10.3389/fpsyg.2020.00247.].
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The Depression Anxiety Stress Scale-21 (DASS-21) is an instrument in the assessment of mental health status. The current study recruited 1,532 Chinese hospital workers [74.4% female; mean age = 31.97 (SD = 9.70) years] to examine the reliability, latent structure, and measurement invariance of the DASS-21 between genders. The Cronbach's α values were greater than 0.90 for total score. This study examined four possible models of the DASS-21 using the confirmatory factor analysis (CFA) in Chinese hospital workers. The results from CFA revealed that the latent structure of the DASS-21 in medical staffs is best represented by a one-factor model. Then we used the one-factor model to examine measurement invariance across genders by using a multiple-group categorical CFA. All values of root mean square error approximation (RMSEA) were less than 0.08, all Comparative Fix Index (CFI) and Tucker-Lewis Index values were greater than 0.90, all ΔCFI (changes in CFI) values were less than 0.010, and ΔRMSEA (the changes in RMSEA) were less than 0.015. These findings supported the gender invariance of the DASS-21 among Chinese hospital workers.
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BACKGROUND: Screening for secondary traumatic stress (STS) is lacking in China. It is unclear whether Western models of STS can be adapted satisfactorily for use in non-Western regions. The 20-item Secondary Trauma Questionnaire (STQ) is a self-report measure of traumatic stress symptoms in individuals who have been influenced indirectly by suicide or violent injury of people important to the respondents. METHODS: Here, we assessed the psychometric properties of a newly developed Chinese version of the STQ in a potentially traumatized sample (N = 875) composed of doctors, nurses, teachers, civic administration staff, and social workers in China. We performed reliability and validity analyses. Subsequently, we split the total sample into two subsamples for exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) for measurement invariance analyses. RESULTS: The full scale demonstrated good internal consistency (Cronbach's α = 0.95-0.97), convergent validity, discriminant validity, and factorial validity. CFA affirmed a one-factor structure; the configural, metric, scalar, and strict invariances of the STQ were acceptable across genders. CONCLUSION: The present results indicate that the STQ is a reliable and valid self-report assessment for use with potentially traumatized people in China, and further supports the notion that the STQ is amenable to additional future cross-cultural adaptation.
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OBJECTIVES: To evaluate the rate of HIV seroconversion and the related risk factors among HIV discordant couples in Hubei Province, China. METHODS: HIV seroconversion rates and associated factors in discordant couples were identified during 2010-2012, based on existing data collected in serological and behavioral surveys between 2005 and 2007. RESULTS: At baseline, HIV transmission had occurred in 505 out of 1258 couples and the annual rate of HIV transmission was 6.3% in the absence of an intervention (40.14% after HIV exposure for 6.4 years). Five out of 753 discordant couples were found to have seroconverted during the 5-year follow-up observation after the implementation of interventions. Factors independently associated with HIV seroconversion included an HIV viral load >1000 copies/ml (odds ratio (OR) 18.706, 95% confidence interval (CI) 1.577-221.926), the index partner being on antiretroviral therapy (OR 0.019, 95% CI 0.002-0.180), and condom use in the past 6 months (OR 0.194, 95% CI 0.021-0.795). CONCLUSIONS: HIV-negative partners in serodiscordant couples were at risk of HIV infection if the index partner did not receive any intervention. It is strongly advised that existing interventions are used, such as couples consultations, condom use, and antiretroviral treatment, to minimize the risk of HIV transmission.
Subject(s)
HIV Infections/transmission , HIV Seropositivity/epidemiology , Adult , China/epidemiology , Family Characteristics , Female , Follow-Up Studies , HIV Infections/epidemiology , Humans , Male , Middle Aged , Prevalence , Risk Factors , Sexual PartnersABSTRACT
The ability to tune material properties using gating by electric fields is at the heart of modern electronic technology. It is also a driving force behind recent advances in two-dimensional systems, such as the observation of gate electric-field-induced superconductivity and metal-insulator transitions. Here, we describe an ionic field-effect transistor (termed an iFET), in which gate-controlled Li ion intercalation modulates the material properties of layered crystals of 1T-TaS2. The strong charge doping induced by the tunable ion intercalation alters the energetics of various charge-ordered states in 1T-TaS2 and produces a series of phase transitions in thin-flake samples with reduced dimensionality. We find that the charge-density wave states in 1T-TaS2 collapse in the two-dimensional limit at critical thicknesses. Meanwhile, at low temperatures, the ionic gating induces multiple phase transitions from Mott-insulator to metal in 1T-TaS2 thin flakes, with five orders of magnitude modulation in resistance, and superconductivity emerges in a textured charge-density wave state induced by ionic gating. Our method of gate-controlled intercalation opens up possibilities in searching for novel states of matter in the extreme charge-carrier-concentration limit.
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OBJECTIVE: To determine the incidence and survival time of acquired immunodeficiency syndrome-related malignancies among HIV-infected population. METHODS: A clinical database search, chart review and verification with health records were undertaken for all AIDS-defining cancers diagnosed in Zhongnan Hospital Wuhan University, Hubei Province, China. Kaplan-Meier method was used to evaluate survival time in HIV-infected patients with cancer. RESULTS: A total of 3,554 patients with 11,072 person-years of HIV follow-up care were reviewed from January 2004 to December 2008. Sixty-three cancer cases were identified. The median ages of HIV-positive cancer cases were 42.4 ± 8.8 years, CD4 count were 220.9 ± 142.3/µl. The common cancers were non-Hodgkin's lymphoma (NHL, 28.6%), cervical cancer (22.2%), liver cancer (17.5%). Statistically significantly elevated SIRs were observed in NHL (SIR in all = 34.5, 95% CI 11.7-89.9, SIR in males = 45.3, 95% CI 24.7-138.9, females = 12.2, 95% CI 3.9-38.2), invasive cervical cancer (SIR = 68.1, 95% CI 19.2-84.5), liver cancer (SIR = 6.0, 95% CI 2.6-12.2), nasopharyngeal cancer (SIR = 6.2, 95% CI 1.5-44.9), bladder cancer (SIR = 4.9, 95% CI 0.9-22.9), esophageal cancer (SIR = 3.1, 95% CI 0.7-14.3), and stomach cancer (SIR = 2.6, 95% CI 0.6-11.6). All cancers combined showed a statistically significantly elevated SIR of 4.1 (95% CI 2.5-4.6), SIR for all cancers was much higher in female (SIR = 4.8, 95% CI 3.2-7.3) than in male (SIR = 3.1, 95% CI 2.1-4.3). Among HIV-positive patients with cancer, the median survival time was 14.5 ± 3.8 months in NHL group, 28.9 ± 3.6 months in cervix group, 5.1 ± 1.1 months in liver group, and 26.7 ± 6.7 months in other groups. The median survival time in HIV-infected group (23.1 ± 3.5 months) was shorter than that in non-HIV-infected group (43.0 ± 5.1 months), (P < 0.05). CONCLUSIONS: NHL, cervical cancers and liver cancer are common cancers among HIV-infected individuals in Hubei, China. Most malignant diseases that arise in the setting of HIV infection tend to occur at a more advanced stage with shorter survival time.