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Twisted bilayers host many emergent phenomena in which the electronic excitations (quasiparticles, QPs) are closely intertwined with the local stacking order. By inspecting twisted hexagonal boron nitride (t-hBN), we show that nonlocal long-range interactions in large twisted systems cannot be reliably described by the local (high-symmetry) stacking and that the band gap variation (typically associated with the moiré excitonic potential) shows multiple minima with variable depth depending on the twist angle. We investigate twist angles of 2.45°, 2.88°, 3.48°, and 5.09° using the GW approximation together with stochastic compression to analyze the QP state interactions. We find that band-edge QP hybridization is suppressed for intermediate angles that exhibit two distinct local minima in the moiré potential (at AA region and saddle point (SP)) which become degenerate for the largest system (2.45°).

Backgroud: Hypotension is one of the most common and dangerous complications following combined spinal epidural anesthesia during elective cesarean delivery. Many methods are used to prevent or treat the hypotension with pharmacological or non-pharmacological measures. Our aim was to assess left-lateral position and phenylephrine prophylactic treatment for the prevention or treatment of maternal hypotension., Methods: A total of 127 pregnant women were enrolled to be analyzed. The primary outcome measure was the incidence of maternal hypotension and secondary outcome measures included maternal demographic characteristics, anesthesia-to-incision time interval, birthweight and Apgar scores., Results: The incidence of hypotension was 65.4 % in sequential reactive treatment and only 11.3 % achieved complete anesis after left-lateral position, significantly higher than 17.4 % in left-lateral position combined phenylephrine prophylactic treatment ( P  < 0.001). The increasing in gestational age may decrease the hypotension risk ( P  < 0.001). There were no significantly differences with maternal age, gravidity, parity, BMI before pregnancy, BMI before cesarean section, anesthesia-to-incision time interval, birthweight and Apgar scores ( P  > 0.05). The univariate logistic regression analysis revealed a significant association between treatment and hypotension (OR 0.11, 95 % CI 0.05-0.27). After adjusting for confounding variables, the risk of hypotension was decreased in subjects with treatment (OR 0.1, 95 % CI 0.04-0.25; OR 0.15, 95 % CI 0.05-0.43; OR 0.16, 95 % CI 0.05-0.46). The results of stratified and interaction analyses of the association between treatment revealed no interactive role from maternal age, gravidity and BMI before cesarean section ( P  > 0.05)., Conclusions: Single use of left-lateral position had limited effective and left-lateral position combined prophylactic phenylephrine used may be much better to prevent or treat hypetension, but larger studies with more robust data are needed to confirm these findings., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s).)

Four new triazole-decorated silver(I)-based cationic metal-organic frameworks (MOFs), {[Ag(L1)](BF 4 )} n ( 1 ), {[Ag(L1)](NO 3 )} n ( 2 ), {[Ag(L2)](BF 4 )} n ( 3 ), and {[Ag(L2)](NO 3 )} n ( 4 ), have been synthesized using two newly designed ligands, 3-fluoro-5-(4 H -1,2,4-triazol-4-yl)pyridine (L1) and 3-(4 H -1,2,4-triazol-4-yl)-5-(trifluoromethyl)pyridine (L2). When the fluorine atom was changed to a trifluoromethyl group at the same position, tremendous enhancement in the MOF dimensionality was achieved [two-dimensional to three-dimensional (3D)]. However, changing the metal salt (used for the synthesis) had no effect. The higher electron-withdrawing tendency of the trifluoromethyl group in L2 aided in the formation of higher-dimensional MOFs with different properties compared with those of the fluoro derivatives. The fluoride group was introduced in the ligand to make highly electron-deficient pores inside the MOFs that can accelerate the anion-exchange process. The concept was proved by density functional theory calculation of the MOFs. Both 3D cationic MOFs were used for dye adsorption, and a remarkable amount of dye was adsorbed in the MOFs. In addition, owing to their cationic nature, the MOFs selectively removed anionic dyes from a mixture of anionic, cationic, and neutral dyes in the aqueous phase. Interestingly, the present MOFs were also highly effective for the removal of oxoanions (MnO 4 - and Cr 2 O 7 2- ) from water.