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[Display omitted] Li-rich Mn-based oxides (LRMOs) are considered as one of the most-promising cathode materials for next generation Li-ion batteries (LIBs) because of their high energy density. Nevertheless, the intrinsic shortcomings, such as the low first coulomb efficiency, severe capacity/voltage fade, and poor rate performance seriously limit its commercial application in the future. In this work, we construct successfully g-C 3 N 4 coating layer to modify Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 (LMNC) via a facile solution. The g-C 3 N 4 layer can alleviate the side-reaction between electrolyte and LMNC materials, and improve electronic conduction of LMNC. In addition, the g-C 3 N 4 layer can suppress the collapse of structure and improve cyclic stability of LMNC materials. Consequently, g-C 3 N 4 (4 wt%)-coated LMNC sample shows the highest initial coulomb efficiency (78.5%), the highest capacity retention ratio (78.8%) and the slightest voltage decay (0.48 V) after 300 loops. Besides, it also can provide high reversible capacity of about 300 and 93 mAh g−1 at 0.1 and 10C, respectively. This work proposes a novel approach to achieve next-generation high-energy density cathode materials, and g-C 3 N 4 (4 wt%)-coated LMNC shows an enormous potential as the cathode materials for next generation LIBs with excellent performance. [ABSTRACT FROM AUTHOR]

Background: To study the incidence and risk factors of shivering in pregnant women during cesarean section. Methods: We performed a prospective nested case-control study involving parturients scheduled for cesarean sections between July 2018 and May 2021. The overall incidence of intraoperative shivering and its potential risk factors were investigated. The potential risk factors evaluated were pain, anxiety, emergency surgery, transfer from the delivery room, epidural labor analgesia, membrane rupture, labor, and the timing of the surgery. Shivering and body temperature at different time points during the cesarean section were also recorded. The selected seven time points were: entering the operating room, post-anesthesia, post-disinfection, post-delivery, post-oxytocin, post additional hysterotonics, and before leaving the operating room. Results: We analyzed 212 cesarean section parturients. The overall incidence of shivering was 89 (42.0%). Multivariate logistic regression showed that anxiety, emergency delivery, and transfer from the delivery room to the operating room increased the overall shivering incidence (odds ratio = 1.77, 2.90, and 3.83, respectively). The peak shivering incidence occurred after skin disinfection (63, 29.7%), and the lowest body temperature occurred after oxytocin treatment (36.24 ± 0.30 °C). Stratified analysis of surgery origin showed that emergency delivery was a risk factor for shivering (odds ratio = 2.99) in women transferred from the obstetric ward to the operating room. Conclusion: Shivering occurred frequently during cesarean sections, with the peak incidence occurring after skin disinfection. Anxiety, emergency delivery, and transfer from the delivery room to the operating room increased the risk of shivering development during cesarean sections. Trial registration: The study protocol was registered online at China Clinical Registration Center (registration number: ChiCTR-ROC-17010532, Registered on 29 January 2017). [ABSTRACT FROM AUTHOR]

The NASICON structure of Na 3 V 2 (PO 4) 2 F 3 (NVPF) separates the valence electrons between the polyanion group and V and regulates the redox coupling energy. As a result, NVPF exhibits a high operating voltage in sodium-ion batteries. However, NVPF cathode material has poor specific capacity and low-rate performance. It is necessary to improve the electrochemical performance by increasing the electronic conductivity and accelerating the ion diffusion rate. Through morphology control, more active sites and ion channels can be provided to enhance rate performance and cycle stability. However, there are few reviews on how to control the morphology of NVPF. Therefore, this paper starts with the factors affecting the morphology of NVPF. The effects of pH value, surfactant, and external additives on its morphology were systematically summarized. On this basis, reasonable strategies, including morphology design, preparation method, structure control, surface modification, and defect engineering, are summarized. This paper provides theoretical support for the development of high-voltage NVPF. It provides inspiration for creating NVPF cathode materials with high specific capacity and high cycle performance. • The effects of various factors on the morphology of Na 3 V 2 (PO 4) 2 F 3 were systematically summarized. • The electrochemical properties of Na 3 V 2 (PO 4) 2 F 3 coated with different carbon sources were summarized. • The low-pressure platform caused by fluorine loss and its fluorine supplement measures are explained. • The effects of binders and electrolyte additives on Na 3 V 2 (PO 4) 2 F 3. [ABSTRACT FROM AUTHOR]