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Interlayer excitons, with prolonged lifetimes and tunability, hold potential for advanced optoelectronics. Previous research on the interlayer excitons has been dominated by two-dimensional heterostructures. Here, we construct WSe2/GaN composite heterostructures, in which the doping concentration of GaN and the twist angle of bilayer WSe2 are employed as two ingredients for the manipulation of exciton behaviors and polarizations. The exciton energies in monolayer WSe2/GaN can be regulated continuously by the doping levels of the GaN substrate, and a remarkable increase in the valley polarizations is achieved. Especially in a heterostructure with 4°-twisted bilayer WSe2, a maximum polarization of 38.9% with a long lifetime is achieved for the interlayer exciton. Theoretical calculations reveal that the large polarization and long lifetime are attributed to the high exciton binding energy and large spin flipping energy during depolarization in bilayer WSe2/GaN. This work introduces a distinctive member of the interlayer exciton with a high degree of polarization and a long lifetime.
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Magnetic proximity interaction provides a promising route to manipulate the spin and valley degrees of freedom in van der Waals heterostructures. Here, we report a control of valley pseudospin in the WS2/MoSe2 heterostructure by utilizing the magnetic proximity effect of few-layered CrBr3 and, for the first time, observe a substantial difference in valley polarization of intra/interlayer excitons under different circularly polarized laser excitations, referred to as chirality-dependent valley polarization. Theoretical and experimental results reveal that the spin-selective charge transfer between MoSe2 and CrBr3, as well as between MoSe2 and WS2, is mostly responsible for the chiral feature of valley polarization in comparison with the proximity exchange field. This means that a long-distance manipulation of exciton behaviors in multilayer heterostructures can be achieved through spin-selective charge transfer. This work marks a significant advancement in the control of spin and valley pseudospin in multilayer structures.
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Patients with venous thromboembolism (VTE) comorbid renal insufficiency (RI) are at higher risk of bleeding and thrombosis. Recommendations in guidelines on anticoagulation therapy for those patients remain ambiguous. The goal of this study is to compare the efficacy and safety between different anticoagulant regimens in VTE patients comorbid RI at different stages of treatment and prophylaxis. We performed English-language searches of Pubmed, EMBASE, and Web of Science (inception to Nov 2022). RCTs evaluated anticoagulants for VTE treatment at the acute phase, extension phase, and prophylaxis in patients with RI and reported efficacy and safety outcomes were selected. The methodological quality of the studies was assessed at the outcome level using the risk-of-bias assessment tool developed by the Cochrane Bias Methods Group. A meta-analysis of twenty-five RCTs was conducted, comprising data from twenty-three articles, encompassing a total of 9,680 participants with RI. In the acute phase, the risk of bleeding was increased with novel oral anticoagulants (NOACs) compared to LMWH (RR 1.29, 95% CI 1.04-1.60). For the prophylaxis of VTE, NOACs were associated with an elevated risk of bleeding compared with placebo (RR 1.31, 95%CI 1.02-1.68). In comparison to non-RI patients, both NOACs and vitamin K antagonists (VKA) could increase the risk of bleeding among RI patients (RR 1.45, 95%CI 1.14-1.84 and RR 1.53, 95%CI 1.25-1.88, respectively) during acute phase, while NOACs may increase the incidence of VTE in RI population (RR 1.74, 95%CI 1.29-2.34). RI patients who are under routine anticoagulation have a significantly higher risk of adverse outcomes. LMWH is the most effective and safe option for VTE treatment or prophylaxis in patients with RI.
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Background: Lymphopenia is common in respiratory viral infection. However, no studies elucidated the impact of prolonged lymphopenia on worse outcome in the way of quantitative risk. Methods: Adult patients with laboratory-confirmed respiratory virus infection (influenza, SARS-CoV-2, and other viruses) between January 1st, 2016, and February 1st, 2023 were enrolled in this retrospective cohort study. Serial data of laboratory examination during hospitalization were acquired. The primary outcome was in-hospital all-cause death, and all information was obtained from the electronic medical records system. Legendre orthogonal polynomials (LOP), restricted cubic splines, and multivariable logistic regression were performed. Results: Finally, 2388 inpatients were involved in this study, including 436 patients with influenza, 1397 with SARS-CoV-2, and 319 with other respiratory virus infections. After being adjusted for age, corticosteroids, chronic kidney disease, chronic respiratory disease, cardiovascular disease, lymphopenia on admission and length of hospital stay, prolonged lymphopenia was significantly associated with death in influenza (OR 7.20, 95 % CI 2.27-22.77, p = 0. 0008 for lasting for 3-7 days; OR 17.80, 95 % CI 5.21-60.82, p < 0.0001 for lasting for more than 7 days) and SARS-CoV-2 (OR 3.07, 95 % CI 1.89-5.01, p < 0.0001 for lasting for 3-7 days; OR 6.28, 95 % CI 3.53-11.18, p < 0.0001 for lasting for more than 7 days), compared with a transient lymphopenia of 1-2 days, while no significant association was found in other respiratory viruses. Prolonged lymphopenia was also associated with multi-organ damage in influenza and SARS-CoV-2 infections. Conclusions: Prolonged lymphopenia was significantly associated with worse clinical prognoses in influenza and SARS-CoV-2 infections, but not in other respiratory virus infections.
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Background: Risk stratification for patients with acute pulmonary embolism (APE) is significantly important for treatment and prognosis evaluation. We aimed to develop a novel clot burden score on computed tomography pulmonary angiography (CTPA) based on deep learning (DL) algorithm for risk stratification of APE. Methods: The study retrospectively enrolled patients newly diagnosed with APE in China-Japan Friendship Hospital consecutively. We collected baseline data and CTPA parameters, and calculated four different clot burden scores, including Qanadli score, Mastora score, clot volume and clot ratio. The former two were calculated by two radiologists separately, while clot volume and clot ratio were based on the DL algorithm. The area under the curve (AUC) of four clot burden scores were analyzed. Results: Seventy patients were enrolled, including 17 in high-/intermediate-high risk and 53 in low-/intermediate-low risk. Clot burden was related to the risk stratification of APE. Among four clot burden scores, clot ratio had the highest AUC (0.719, 95% CI: 0.569-0.868) to predict patients with higher risk. In the patients with hemodynamically stable APE, only clot ratio presented statistical difference (P=0.046). Conclusions: Clot ratio is a new imaging marker of clot burden which correlates with the risk stratification of patients with APE. Higher clot ratio may indicate higher risk and acute right ventricular dysfunction in patients with hemodynamically stable status.
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Background: Elevated risk of venous thromboembolism (VTE) in patients with coronavirus disease 2019 (COVID-19) pneumonia has been recognized, while the risk factors associated with VTE in patients with non-COVID-19 pneumonia remain to be defined. This study aimed to conduct a meta-analysis and systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify potential risk factors for VTE in patients with pneumonia from the pre-COVID-19 era. Methods: PubMed, EMBASE, and Cochrane Library were searched. Two reviewers performed screening, full-text review, and extraction. Risk factors and odds ratio (OR) were estimated. Results: Of 595 articles identified, six studies were included. Pooled analysis suggested that age ≥60 years [OR =2.75, 95% confidence interval (CI): 2.55-2.97, P<0.001], mechanical ventilation (MV) (OR =9.48, 95% CI: 8.24-10.91, P<0.001), hypertension (OR =1.41, 95% CI: 1.09-1.83, P=0.010), diabetes (OR =1.49, 95% CI: 1.36-1.64, P<0.001), heart failure (OR =3.15, 95% CI: 1.05-9.41, P=0.040) and cancer (OR =2.86, 95% CI: 2.07-3.95, P<0.001) were associated with higher risk for deep vein thrombosis in patients with pneumonia. While age ≥60 years (OR =2.46, 95% CI: 2.21-2.73, P<0.001), bacterial pneumonia (OR =3.80, 95% CI: 1.65-8.73, P=0.002), hyperlipidemia (OR =1.55, 95% CI: 1.00-2.41, P=0.049), heart failure (OR =2.70, 95% CI: 2.05-3.56, P<0.001), chronic obstructive pulmonary disease (OR =4.73, 95% CI: 3.11-7.17, P<0.001) and cancer (OR =2.90, 95% CI: 2.39-3.53, P<0.001) were risk factors for pulmonary embolism in patients with pneumonia. Conclusions: Patients with non-COVID-19 pneumonia, particularly those with advanced age, MV, cardiovascular comorbidities or cancer, warrant individualized management during hospitalization. Our findings could contribute to refining risk prediction models and further risk stratification for VTE in patients with pneumonia in clinical practice.