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A Pd–COOCH3 species in the vapor-phase carbonylation of methyl nitrite is revealed to have two-fold reactivity, where the nucleophilicity of the Pd–C bond enables C–C coupling to give DMO and the electrophilicity of the π* orbital facilitates C–O coupling to afford DMC.

Crystalline materials AHg4Ga5S12 (A = Rb, Cs) with diamond-like anionic frameworks constructed by the aligned arrangement of tetrahedral units exhibit moderate second-order nonlinear optical (NLO) responses and high laser-induced damage thresholds.

Two novel quaternary nonlinear optical phosphides AIn3Si4P9 (A = Ca, Sr) with a unique double-helix structure are reported for the first time, resulting in a high laser-induced damage threshold, ∼7 times that of benchmark AgGaS2.

Boron nitride nanosheets (BNNSs) are regarded as promising two-dimensional materials in thermally conductive yet electrically insulating applications. Attributed to the strong interlayer "lip-lip" interactions in bulk hexagonal boron nitride (h-BN), high-efficiency exfoliation and scalable fabrication of BNNSs via the top-down strategies remain formidable challenges. Herein, an interesting observation is manifested that gallium-based liquid metal (LM) forming robust coordination interactions with h-BN helps reduce the lip-lip interlayer interactions and thus facilitates successful exfoliation under intense shearing force. For example, employing the ball-milling technique, the BNNS yield can increase to 41.21% with the assistance of LM at only 2 h milling time. Its exfoliation efficiency (yield/time) reaches as high as 26.72%/h, more than 2-fold that of other previously reported methods, including sonication and other ball-milling methods. Moreover, the exfoliated BNNSs are still found to be highly electrically insulating with a band gap of 4.65 eV, showing prospective potential in thermally conductive yet electrical insulating applications. As a proof of concept, a microwave-transparent heat spreader (cellulose nanofiber/BNNSs) is fabricated and verified for applications in high-frequency thermal-management fields.

Lithium (Li) metal anodes are candidates for the next-generation high-performance lithium-ion batteries (LIBs). However, uncontrolable Li dendrite growth leads to safety issues and a low Coulombic efficiency (CE), which hinders the commercialization of Li metal batteries. Stable Li anodes based on the tailored plane deposition and photoassisted synergistic current collectors are currently the subject of research; however, there are few related studies. To suppress the growth of Li dendrites and achieve dense Li deposition, we design a low-cost customized-facet/photoassisted synergistic dendrite-free anode. The tailored (002) plane endows it with a nanorod array/microsphere composite structure and exhibits a strong affinity for Li, which effectively reduces the Li

Complete postoperative analgesia is very important for puerperae after cesarean section. The objective of this study was to explore the optimal postoperative analgesia after cesarean section.A total of 180 full-term puerperae who underwent cesarean section in Hanzhong People's Hospital from March 2019 to March 2020 were enrolled and were randomly divided into three groups. Group A was given 0.9% normal saline, group B and C were given 0.4% ropivacaine for transversus abdominis plane block (TAPB). Postoperative patient-controlled intravenous analgesia (PCIA) pumps were 2 μg/kg sufentanil + 2.5 mg droperidol, 1.5 μg/kg and 1.3 μg/kg sufentanil, respectively. All puerperae were given different but effective analgesia programs. The primary outcome indicators were visual analog scores (VAS), the first compression time of postoperative analgesia pump and the total number of compressions in 48 h. The secondary outcome indicators were vital signs, Ramsay sedation scores, comfort scores (BCS), the frequency of analgesic rescue, postoperative side effects and satisfaction.The dynamic and static VAS scores of the puerperae in group B at TPCIA with sufentanil alone or combined with TAPB can be safely and effectively used for postoperative analgesia after cesarean section. PCIA combined with TAPB had better analgesic effect and lower incidence of side effects while reducing the dose of opioids. The results of this study provide new ideas and insights for the choice of analgesia after cesarean section.

Isoaspartate (isoAsp) is a damaging amino acid residue formed in proteins as a result of spontaneous deamidation. IsoAsp disrupts protein structures, making them prone to aggregation. Here we strengthened the link between isoAsp and Alzheimer's disease (AD) by novel approaches to isoAsp analysis in human serum albumin (HSA), the most abundant blood protein and a major carrier of amyloid beta (Aβ) and phosphorylated tau (p-tau) in blood. We discovered a reduced amount of anti-isoAsp antibodies (P < 0.0001), an elevated isoAsp level in HSA (P < 0.001), more HSA aggregates (P < 0.0001), and increased levels of free Aβ (P < 0.01) in AD blood compared to controls. We also found that deamidation significantly reduces HSA capacity to bind with Aβ and p-tau (P < 0.05). These suggest the presence in AD of a bottleneck in clearance of Aβ and p-tau, leading to their increased concentrations in the brain and facilitating their aggregations there.

With the continuous and rapid increase in the scale of subway operation, the security situation faced by the operating units is becoming increasingly severe. Based on the analysis of the characteristics of subway operation and the current situation of information construction, this paper deeply analyzes the main problems of subway operation safety information construction. Aiming at the problems of poor data circulation, difficult supervision, distrust, fear of leakage, poor timeliness, poor quality and insufficient certificates, this paper puts forward the construction requirements of subway operation safety platform. The platform model is designed from three aspects of block chain platform, platform logic architecture and Internet of Things forensics, and the new mode of safe and efficient management of subway operation is explored.