Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), which can induce multisystem disease. Human angiotensin-converting enzyme 2 (ACE2) widely expressing in arterial and venous endothelial cells and arterial smooth muscle cells has been identified as a functional receptor for SARS-CoV-2. Dysfunction of ACE2 leads to abnormal activation of the renin-angiotensin system and a systemic endotheliitis that may relate to abnormal coagulation and sepsis. Meanwhile, innate immune response and inflammation activation participate in dysfunctional coagulation. Previous research indicated that dysfunctional coagulation was one of the important risk factors accountable for a high risk of severe disease and death in patients with COVID-19. Understanding the possible mechanisms of dysfunctional coagulation and appropriate anticoagulation therapeutic strategies are important to prevent disease deterioration and reduce fatality rates during the ongoing COVID-19 pandemic.

We introduce a multi-scale approach to obtain accurate atomic and electronic structures for atomically relaxed twisted bilayer graphene. High-level exact exchange and random phase approximation (EXX+RPA) correlation data provides the foundation to parametrize systematically improved force fields for molecular dynamic simulations that allow to relax twisted layered graphene systems containing millions of atoms making possible a fine sweeping of twist angles. These relaxed atomic positions are used as input for tight-binding electronic band-structure calculations where the distance and angle dependent interlayer hopping terms are extracted from density functional theory calculations and subsequent representation with Wannier orbitals. We benchmark our results against published force fields and widely used tight-binding models and discuss their impact in the spectrum around the flat band energies. We find that our relaxation scheme yields a magic angle of twisted bilayer graphene consistent with experiments between 1.0 • ∼ 1.1 • using commonly accepted Fermi velocities of graphene υF 1.0 ∼ 1.1 × 10 6 m/s that is enhanced by about 14%∼20% compared with often used local density approximation estimates. Finally, we present high-resolution spectral function calculations for comparison with experimental ARPES. Additional force field parameters are provided for hBN-layered materials.

Objective:To determine the effect of remote ischemic post-conditioning (RIPC) on acute ischemic stroke (AIS) patients undergoing intravenous thrombolysis (IVT).Methods:A single-center, randomized controlled trial was performed with AIS patients receiving IVT. Patients in the RIPC group were administered RIPC treatment (after IVT) during hospitalization. The primary endpoint was a score of 0 or 1 on the modified Rankin scale (mRS) at day 90. The safety, tolerability and neuroprotection biomarkers associated with RIPC were also examined.Results:We collected data from both RIPC (n=34) and controls (n=34). The average duration of hospitalization was 11.2 days. There was no significant difference between the two groups at admission for the NIHSS score (p=0.364) or occur to treatment time (p=0.889). An excellent recovery (mRS 0–1) at 3 months was obtained in 71.9% of the patients in the RIPC group vs 50.0% in the control group (adjusted risk ratio, 9.85; 95% CI, 1.54 to 63.16; P = 0.016). We further found significantly lower plasma S100 β (p=0.007) and higher vascular endothelial growth factor (p = 0.003) levels in the RIPC group than in controls.Conclusions:Repeated RIPC combined with IVT can significantly facilitate recovery of nerve function and improve clinical prognosis of patients with AIS.ClinicalTrial.gov identifier:NCT03218293Classification of Evidence:This study provides Class IV evidence that RIPC following tPA treatment of AIS significantly increases the proportion of patients with MRS 0 or 1 at 90 days.