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Atmospheric gravity waves (GWs) can strongly modulate middle atmospheric circulation and can be a significant factor for the coupling between the lower atmosphere and the middle atmosphere. GWs are difficult to resolve in global atmospheric models due to their small scale; thus, GW observations play an important role in middle atmospheric studies. The climatology of GW variance and momentum in the low-latitude mesosphere and lower thermosphere (MLT) region are revealed using multiple meteor radars, which are located at Kunming (25.6°N, 103.8°E), Sanya (18.4°N, 109.6°E), and Fuke (19.5°N, 109.1°E). The climatology and longitudinal variations in GW momentum fluxes and variance over the low-latitude region are reported. The GWs show strong seasonal variations and can greatly control the mesospheric horizontal winds via modulation of the quasi-geostrophic balance and momentum deposition. The different GW activities between Kunming and Sanya/Fuke are possibly consistent with the unique prevailing surface winds over Kunming and the convective system over the Tibetan Plateau according to the European Centre for Medium-Range Weather Forecasts (ECMWF), Reanalysis v5 (ERA5) data, and outgoing longwave radiation (OLR) data. These findings provide insight for better understanding the coupling between the troposphere and mesosphere. [ABSTRACT FROM AUTHOR]

This article describes how to raise the TEM cells' operating bandwidth and lower their VSWR. A multi-stage curved-edge transition structure for minimizing VSWR and a magnetic loss mechanism for extending the operating bandwidth are proposed by evaluating the workings and constraints of TEM cells. A hybrid simulation strategy based on the particle swarm algorithm and 3D electromagnetic simulation (EM) software is suggested in order to identify the optimal quickly. In the 3D EM simulation software, the TEM cell's 3D model is created, the VSWR and return loss were solved for. It is possible to raise the operational bandwidth from 0–2 GHz to 0–5 GHz. At 0-3 GHz, measurement and simulation results are practically equal. At 3-4.5 GHz, measurement results differ somewhat from simulation results. At 4.5-5 GHz, measurement results greatly diverge from simulation results, and the parameters no longer fulfill standard criteria. [ABSTRACT FROM AUTHOR]

As the conversion efficiency of solar cell approaching its theoretical limits, reducing the power loss during the collection and transmission process is a promising way to improve the performance of solar cell. Cleaved edges create recombination centers, causing up to 0.8%abs (absolute efficiency) of power loss or even more for 156 × 156 mm silicon solar cell. Due to the complexity of edge passivation technique, alternative methods are desired. This article proposes a method to minimize this problem. It is found that most of the recombination current of edge comes from the recombination near the contact and the space charge region (SCR). As a result, keeping the cleaved edge a certain distance away from the contacts and SCR can improve performance effectively. On the other hand, contactless edge can reduce the recombination from the SCR without extra manufacturing difficulty. The results indicate the edge recombination loss can be reduced to less than 0.4%abs after the distance is optimized appropriately. [ABSTRACT FROM AUTHOR]

Objective To explore the effect of transitional care based on time-sensitive incentive theory on self-efficacy and self-management ability of women with postpartum hemorrhage. Methods A total of 112 pregnant women with postpartum hemorrhage who gave birth in the hospital from February 2018 to May 2019 were selected and divided into two groups according to the random number table method, each with 56 cases. The control group implemented routine postpartum care, and the observation group implemented transitional care based on time-sensitive incentive theory. The self-efficacy before and after nursing, changes in self-management ability and the incidence of complications were compared between the two groups. Results The general self-efficacy score of the observation group after 3 months of nursing was higher than that of the control group (P＜0. 05). The scores of self-concept, self-care skills, self-care consciousness of responsibility, health knowledge level and total score of exercise of self-care agency scale in the observation group were higher than those in the control group (P＜0. 01). There was no significant difference in complication rate between two groups(P＞0. 05). Conclusion Transitional care based on the time-sensitive incentive theory can enhance self-efficacy and self-management ability of women with postpartum hemorrhage. (目的 探讨基于时效性激励理论的延续性护理对产后出血产妇自我效能及自我管理能力的影响。方法 选择2018年2月—2019年5月医院分娩产后出血的产妇112例, 按随机数字表法分为2组, 各56例。对照组实施常规产后护理, 观察组实施基于时效性激励理论的延续性护理。对比2组护理前后自我效能感量表(GSES)评分、自我管理能力测定量表(ESCA)评分及并发症发生情况。结果 观察组护理3个月后 GSES评分高于对照组(P＜0. 05)。观察组护理3个月后自我概念、自我护理技能、自护责任感、健康知识水平及ESCA总分均高于对照组(P＜0. 01)。2组并发症发生率差异无统计学意义(P＞0. 05)。结论 基于时效性激励理论的延续性护理能升产后出血产妇自我效能及自我管理能力, 减少并发症发生风险。)

Interfacial solar evaporation technology is considered one of the most promising strategies for alleviating the scarcity of freshwater resources. However, solar-driven evaporation technology cannot eliminate the pollutants in the residual wastewater. To solve this problem, we have prepared a two-in-one solar-driven evaporation/photocatalysis system by decorating MoS2/covalent organic framework (COF) heterojunctions on wood (MoS2/COF-wood). Thanks to the unique porous structure of wood, it provides a strong guarantee for water transport and vapor release during the evaporation process. The introduction of MoS2 and COFs can promote the breaking of hydrogen bonds between water molecules, which leads to a significant decrease in the enthalpy of evaporation, achieving a water evaporation rate as high as 2.17 kg m−2 h−1 under 1 sun irradiation. Meanwhile, the resulting MoS2/COF-wood exhibits good salt resistance and reusability. In addition, the heterojunctions formed between COFs and MoS2 can effectively inhibit charge carrier complexation and improve the photocatalytic degradation ability of pollutants (over 99%). This study highlights the construction strategy of bifunctional wood-based materials for freshwater production and wastewater remediation. [ABSTRACT FROM AUTHOR]

Summary: Somatic cell totipotency in plant regeneration represents the forefront of the compelling scientific puzzles and one of the most challenging problems in biology. How somatic embryogenic competence is achieved in regeneration remains elusive.Here, we discover uncharacterized organelle‐based embryogenic differentiation processes of intracellular acquisition and intercellular transformation, and demonstrate the underlying regulatory system of somatic embryogenesis‐associated lipid transfer protein (SELTP) and its interactor calmodulin1 (CAM1) in cotton as the pioneer crop for biotechnology application. The synergistic CAM1 and SELTP exhibit consistent dynamical amyloplast–plasmodesmata (PD) localization patterns but show opposite functional effects.CAM1 inhibits the effect of SELTP to regulate embryogenic differentiation for plant regeneration. It is noteworthy that callus grafting assay reflects intercellular trafficking of CAM1 through PD for embryogenic transformation.This work originally provides insight into the mechanisms responsible for embryogenic competence acquisition and transformation mediated by the Ca2+/CAM1‐SELTP regulatory pathway, suggesting a principle for plant regeneration and cell/genetic engineering. [ABSTRACT FROM AUTHOR]