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• 3D/4D additive–subtractive manufacturing was developed for heterogeneous ceramics. • The printing of heterogeneous precursors contributed to the shape-changing strategy. • Local receramization of homogeneous ceramics facilitated the shape-keeping strategy. • High complexity, resolution, efficiency, and material diversity were achieved. The manufacturing of heterogeneous high-temperature material components is challenging for use in practical applications. Three-dimensional (3D) printing provides solutions to programmable constructing ceramic architectures. However, the development of heterogeneous ceramics is limited by low flexibility of heterogeneity, geometrical complexity, structural resolution, manufacturing efficiency, and material diversity. In this study, we demonstrated flexible and rapid approaches for fabricating complicated and precise heterogeneous ceramics by shape-changing (4D) or shape-keeping (3D) additive–subtractive manufacturing (ASM) methods. The shape-changing strategy for heterogeneous ceramics was achieved by global ceramization of heterogeneous precursors, while the shape-keeping strategy for heterogeneous ceramics was achieved by local receramization of homogeneous ceramics. Finite element analysis (FEA) simulations of the influence of the thermal shrinkage dominant in the shape-changing strategy on the shape deformation of heterogeneous ceramics could be valuable predictions of the experimental results. The 3D/4D ASM methods are generic for high-temperature materials and extendable to metallic and diamond materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Objective:Negative pressure wound therapy (NPWT) is considered to be an effective technique to promote the healing of various wounds. The aim of this study was to evaluate different wound dressings combined with NPWT in treating wounds in Wuzhishan pigs.Method:Excisions were made in the backs of the pigs and were covered with polyvinyl alcohol (PVA) dressing, polyurethane (PU) dressing or PU dressing with non-adherent membrane (PU-non-ad). NPWT was applied to the wound site. In the control group, basic occlusive dressing (gauze) without NPWT was applied. On days 0, 3, 7, 14, 21 and 28 post-surgery, the wound size was measured during dressing change, and wound healing rate (WHR) was calculated. In addition, blood perfusion within 2cm of the surrounding wound was measured by laser doppler flowmetry. Dressing specimen was collected and microbiology was analysed. Granulation tissues from the central part of the wounds were analysed for histology, vascular endothelial growth factor (VEGF) and cluster of differentiation 31 (CD31) mRNA expression.Results:The PU-non-ad-NPWT significantly (p<0.01) accelerated wound healing in the pigs. Further pathological analysis revealed that the non-adherent membrane effectively protected granulation tissue formation in PU-NPWT treated wounds. The blood perfusion analysis suggested that the non-adherent membrane improved the blood supply to the wound area. Microbiological analysis showed that non-adherent membrane decreased the bacterial load in the PU-NPWT dressing. VEGF and CD31 mRNA expression was upregulated in the wound tissue from the PU-non-ad-NPWT treated groups.Conclusion:In this study, the PU dressing with non-adherent membrane was an ideal dressing in NPWT-assisted wound healing.

Reflectance spectroscopy is rapid, inexpensive, and non-destructive and can provide important information about the mineralogy of rocks and sediments. We measured the reflectance spectroscopy of Miocene red clay deposits on the northeastern margin of the Tibetan Plateau, with the aim of developing a rapid methodology for detecting paleoclimatic changes. We obtained visible/near-infrared (VNIR) and short-wave infrared (SWIR) spectroscopy data from the red clay in the Jianzha Basin, and analyzed their relationship with independent paleoclimatic records, including mineral contents and environmental magnetic parameters. The results show that the VNIR parameters, including D500, D900, R500, and R900 (where D and R represent the depth and reflectance of the absorption peaks around 500 and 900 nm, respectively) are temperature-sensitive and correlated with the magnetic susceptibility, frequency-dependent magnetic susceptibility, and the marine δ18O record. The results of frequency-domain analysis of the VNIR parameters show that they reflect climate change on orbital timescales. SWIR parameters, such as AS1400, D1400/D1900 and D1900 (where AS represents the asymmetry of the absorption peaks around 1400 nm), are correlated with the illite and montmorillonite content, and they are sensitive to the weathering intensity. The spectral parameters of the eolian red clay in the Jianzha Basin reflect regional climatic changes caused by the uplift of the Tibetan Plateau at ∼8.5 Ma and global climatic cooling at ∼7.2 Ma, and thus they are applicable as both regional and global paleoenvironmental indicators.

The exploration–exploitation tradeoff is an inherent challenge in data-driven adaptive control. Though this tradeoff has been studied for multiarmed bandits (MABs) and reinforcement learning for linear systems, it is less well studied for learning-based control of nonlinear systems. A significant theoretical challenge in the nonlinear setting is that there is no explicit characterization of an optimal controller for a given set of cost and system parameters. We propose the use of a finite-horizon oracle controller with full knowledge of parameters as a reasonable surrogate to an optimal controller. This allows us to develop policies in the context of learning-based model-predictive control (MPC) and conduct a control-theoretic analysis using techniques from MPC and optimization theory to show that these policies achieve low regret with respect to this finite-horizon oracle. Our simulations exhibit the low regret of our policy on a heating, ventilation, and air-conditioning model with partially unknown cost function.

AbstractJD.comutilizes advanced analytical techniques to strengthen its supply chain capability. The end-to-end inventory management model, intelligent risk management system and consumer-to-manufacturer system are implemented to attain agility, resilience and shared value. These efforts have led to significant revenue increases, cost savings, and value creation across the retail ecosystem, benefiting consumers and business partners.

The oxidation behavior and kinetics of Ti2AlC–20vol.%TiB2composite at 600–900 °C in air were investigated. The results showed that the oxidation kinetics of the composite followed a logarithmic law within the given temperature range, which indicated that the composites had excellent oxidation resistance. The selective oxidation of Al in Ti2AlC was greatly enhanced, which facilitated the formation of a continuous and dense protective layer of Al2O3. Meanwhile, the existence of molten B2O3inhibited the outward diffusion of Ti and inward diffusion of oxygen, which prevented the growth of anatase TiO2at 600 °C and rutile TiO2at 700–900 °C. Therefore, the incorporation of TiB2completely inhibited the abnormally rapid oxidation of bulk Ti2AlC at 600 °C and improved its oxidation resistance at 700–900 °C.

Dense HfCxN1−xcarbonitride ceramics are very promising as potential ultra-high temperature ceramics (UHTCs) for application under extremely harsh environments. However, the thermophysical and mechanical properties of the HfCxN1−xcarbonitrides have not been investigated clearly. The present work prepared HfCxN1−x(x = 0.3, 0.4, 0.5, 0.6, 0.7) ceramics at 1950 °C under 30 MPa in flowing Ar atmosphere by using hot pressing sintering method. The relative densities of the samples obtained reached above 96%. Thermal conductivity of the as-prepared HfCxN1−xcarbonitrides ranged from 19 to 24 W m−1K−1 at room temperature. The increased role of electrons in thermal conduction caused by both increasing nitrogen content and increasing temperature, resulted in improved thermal conductivity, varying from 32 to 39 W m−1K−1. With increasing nitrogen content, the electrical conductivity also increased, ranging from 149 to 213 × 104 Ω−1m−1. With the increase of nitrogen content, Hf-C covalent bonds are gradually replaced by Hf-N covalent bonds with lower bond strength, resulting in HfC0.7N0.3exhibiting the highest room-temperature flexural strength and hardness, HfC0.3N0.7exhibiting the highest fracture toughness. Their mechanical properties are greatly improved over the binary HfC and HfN. The high-temperature flexural strength of the HfC0.7N0.3decreased from 324 MPa at 1000 °C, to 139 MPa at 1600 °C and 100 MPa at 2000 °C. Meanwhile, it was revealed that the high-temperature flexural strength decreased with increasing nitrogen content for the as-prepared HfCxN1−xcarbonitrides, similar to the changing trend of room-temperature flexural strength. The HfC0.3N0.7possessed high-temperature plasticity at 2000 °C, attributed to the ability of the coarser grain to produce numerous layer dislocations.

• The medium-entropy MAX phase ceramic was fabricated for the first time. • Nearly pure medium-entropy (TiVNb) 2 AlC was prepared by hot pressing. • (TiVNb) 2 AlC exhibits lower thermal conductivity compared to the individual MAX phases. • Young's modulus, Vickers hardness, and bending strength were reported. Medium- or high-entropy materials have great potential for applications due to their diverse compositions and unexpected physicochemical properties. Herein, a novel medium-entropy (TiVNb) 2 AlC was synthesized via hot pressing at 1400 °C from three individual M 2 AlC (M=Ti, V, Nb) MAX phases. The microstructure of (TiVNb) 2 AlC was characterized from the microscale to the atomic scale by scanning electron microscope microscopy (SEM), scanning transmission electron microscopy (STEM), and energy dispersive spectroscopy (EDS). The results showed that Ti, V, and Nb atoms were fully solid-soluble in the M-sites of the M 2 AlC MAX phase. Compared with three individual MAX phases, the thermal conductivity of (TiVNb) 2 AlC was reduced greatly in the temperature range of 293–1473 K, and its mechanical properties (including Young's modulus, Vickers hardness, and bending strength) were all increased due to the solid solution strengthening and electronic mechanism. [Display omitted] [ABSTRACT FROM AUTHOR]

To improve the atomic oxygen (AO) erosion resistance of Kapton for application as an aerospace material in low earth orbit (LEO), a graphene-modified polysiloxane-60 vol.% SiO2(G-PSS) composite coating was prepared and tested for AO exposure at a total flux of 1.86 × 1020atoms/cm2. The prepared coating with a thickness of 5 μm was smooth, with good adhesion and no macroscopic defects. Its AO erosion yield was 9.77 × 10−27–1.25 × 10−26cm3/atom, which was about three orders and one order of magnitude lower than that of Kapton and polysiloxane-60vol.%SiO2(PSS) hybrid coating, respectively. The beneficial effect of graphene was attributed to the effective inhibition of gas permeation by the single-layer graphene due to its unique structure and the more stable epoxy groups produced during the reaction of graphene with AO.

We describe a high-peak-power macro/micro pulse 1319 nm laser operation, which is produced by the acousto-optic Q-switched Nd:YAG oscillator that is side-pumped with quasi- continuous-wave laser diode. Under remaining a fixed macro pulse repetition frequency of 400 Hz, the lasing characteristics for different micro pulse schemes are investigated. To realize 1319 nm single wavelength oscillation, a birefringence-plate is employed to suppress the adjacent 1338 nm line. Under 390 W of pump power with $200 ~\mu \text{s}$ of pulse duration, an average Q-switched 1319 nm power is increased from 32.5 W to 51.5 W by increasing the repetition rate of micro pulse from 400 Hz to 1600 Hz, and the corresponding micro pulse width can be stretched from 124 ns to 154 ns. The calculated maximum peak power is 0.655 MW with a pulse energy of 81.2 mJ, which is the highest-result reported to date for Q-switched 1319 nm lasers.

The production of nitrogen-doped carbon quantum dots (N-CDs) from walnut shell waste is crucially important for green chemistry and sustainable development. Herein we fabricate N-CDs by a bottom-up solvothermal method and use the novel N-CDs to modify the electron transport layer (ETL) in perovskite solar cells (PVSCs). The N-CDs can produce 440 nm fluorescence under the excitation of 350 nm light with a quantum yield of 8.75%. Infrared absorption spectra show that N-CDs contain high proportions of nitrogen-containing and oxygen-containing functional groups. , Through the incorporation of N-CDs into SnO2 ETL, the formation of defects is inhibited, and crystallinity is improved. This is because the N-CDs contains a large number of functional groups such as nitrogen and oxygen and these groups would interact with the ETL and perovskite, which reduce the defect/trap centers in PVSCs. Therefore, the N-CDs modified PVSCs show improved power conversion efficiency. This study provides a novel way to use walnut shell waste to synthesize N-CDs and achieve efficient and stable perovskites solar cells.

The reoperation rate was significantly lower and patient satisfaction scores were significantly higher for SVF-gel compared with nanofat+high-density fat in restoring periorbital volume. There was no significant difference between 2 groups for periorbital rejuvenation.

Today’s supply chain is becoming complex and fragile. Hence, supply chain managers need to create and unlock the value of the smart supply chain. A smart supply chain requires connectivity, visibility, and agility, and it needs be integrated and intelligent. The digital twin (DT) concept satisfies these requirements. Therefore, we propose creating a DT-driven supply chain (DTSC) as an innovative and integrated solution for the smart supply chain. We provide background information to explain the DT concept and to demonstrate the method for building a DTSC by using the DT concept. We discuss three research opportunities in building a DTSC, including supply chain modeling, real-time supply chain optimization, and data usage in supply chain collaboration. Finally, we highlight a motivating case from JD.COM, China’s largest retailer by revenue, in applying the DTSC platform to address supply chain network reconfiguration challenges during the COVID-19 pandemic.

China’s dual urban–rural structure has resulted in rural residents with a lower social rank vis-à-vis urban residents. This research examined prosociality between lower class individuals (rural children) and higher class individuals (urban children), operationalized using the dictator game, which focuses on sharing resources with others. Two studies consistently showed that both rural and urban children were more likely to share more resources with rural partners than with urban partners. This tendency was more pronounced among urban, higher class children. This effect occurred in both within- and between-subject designs, when the allocated resources were money and notebooks, and in situations with and without a short period of social contact. The findings did not provide evidence for the view that lower class is associated with higher prosociality. Rather, the prosociality depended on the social class of both the actor and the target. This has implications for integrating migrant children into city life.

Many countries and governments consider smart cities a solution to global warming, population growth, and resource depletion. Numerous challenges arise while creating a smart city. Digital twins, along with the Internet of Things, fifth-generation wireless systems, blockchain, collaborative computing, simulation, and artificial intelligence technologies, offer great potential in the transformation of the current urban governance paradigm toward smart cities. In this paper, the concept of a digital twin city (DTC) is proposed. The characteristics, key technologies, and application scenarios of a DTC are elaborated upon. Further, we discuss the theories, research directions, and framework regarding DTCs.

A series of novel pyrazolopyridine compounds have been designed and prepared by a general synthetic route. Their activities against the replication of poliovirus-1, EV-A71, and CV-B3 enteroviruses were evaluated. The comprehensive understanding of the structure–activity relationship was obtained by utilizing the variation of four positions, namely, N1, C6, C4, and linker unit. From the screened analogues, the inhibitors with the highest selectivity indices at 50% inhibition of viral replication (SI50) were those with isopropyl at the N1 position and thiophenyl-2-yl unit at C6 position. Furthermore, the C4 position offered the greatest potential for improvement because many different N-aryl groups had better antiviral activities and compatibilities than the lead compound JX001. For example, JX040with a 2-pyridyl group was the analogue with the most potent activity against non-polio enteroviruses, and JX025, possessing a 3-sulfamoylphenyl moiety, had the best activity against polioviruses. In addition, analogue JX037, possessing a novel pyrazolopyridine heterocycle, was also shown to have good antienteroviral activity, which further enlarges the compound space for antienteroviral drug design.

CuCs-MCM as an efficient difunctional catalyst was developed for the transfer hydrogenation of biomass-derived furfural to furfuryl alcohol with formic acid as hydrogen donor, which played crucial roles in the decomposition of formic acid to hydrogen and hydrogenation of furfural to furfural alcohol.

Two new hydrostable two-dimensional (2D) uranyl coordination complexes were synthesized. Both of them show effective photocatalytic degradation of rhodamine B (RhB) in aqueous solution. The photocatalytic reaction mechanism was also studied by condition experiments and theoretical analysis.

Short-carbon-fibers (Csf) reinforced Ti3SiC2matrix composites (Csf/Ti3SiC2, the Csfcontent was 0 vol%, 2 vol%, 5 vol%, and 10 vol%) were fabricated by spark plasma sintering (SPS) using Ti3SiC2powders and Csfas starting materials at 1300 °C. The effects of Csfaddition on the phase compositions, microstructures, and mechanical properties (including hardness, flexural strength (sf), and KIC) of Csf/Ti3SiC2composites were investigated. The Csf, with bi-layered transition layers, i.e., TiC and SiC layers, were homogeneously distributed in the as-prepared Csf/Ti3SiC2composites. With the increase of Csfcontent, the KICof Csf/Ti3SiC2composites increased, but the sfdecreased, and the Vickers hardness decreased initially and then increased steadily when the Csfcontent was higher than 2 vol%. These changed performances (hardness, sf, and KIC) could be attributed to the introduction of Csfand the formation of stronger interfacial phases.

Threat appeals have been widely utilized in numerous types of public service announcements (PSAs), and previous research has focused on the impact of the inherent messages in these announcements. By examining the research on the effects of framing PSAs in terms of the threat of the message to oneself or others, we proposed a clear conceptualization of “threat‐target framing.” The first two studies addressed the direct effects of threat‐target framing and found that other‐oriented threat appeals can evoke more guilt than can self‐oriented threat appeals. Moreover, self‐oriented threat appeals can evoke more fear and immediately direct recipients' attention to the smoker than can other‐oriented threat appeals. Study 3 reported that a contextual factor—relationship norms—was introduced as a potential moderating factor. Results showed that relationship norms had the potential to moderate the effect of threat‐target framing on recipients' fear response, but not the effect on recipients' guilt and coping response. In sum, the results highlighted the importance of message framing of advertising copies and the placement context. Our findings may be useful in understanding the antecedents of the persuasiveness of PSAs.

The Belt and Road Initiative (BRI) is a massive, ambitious, long-term project initiated by the Chinese government, with participation from many other countries, to facilitate trade and improve logistics in an effort to promote global economic development. In this paper, we identified the supply chain and logistics innovations linked to the BRI. These innovations include new routes and modes for global trade, new supply chain design, reduction of cross-border logistics frictions, and entrepreneurial development. Examples of some of these innovations are emerging, while new ones are being developed. These innovations can enable businesses to improve their operational performances and create economic value. At the same time, to realize the full potentials of BRI, new work processes and technologies, incentive alignment, collaborations among businesses, and optimized planning are needed. This provides great opportunities for researchers to explore how to overcome barriers and achieve the full values of BRI.

A 100 W level kilohertz repetition-rate microsecond (µs)-pulse all-solid-state sodium beacon laser at 589 nm is demonstrated for the first time, to the best of our knowledge, via combining two independent µs-pulsed lasers. Each beamlet is generated by the sum-frequency mixing of pulsed 1064 and 1319 nm lasers in a lithium triborate (LBO) crystal, which operate at 500 Hz pulse repetition frequency with 61 W $p$p-polarized and 53 W $s$s-polarized output, respectively. An incoherent sequence combining technology of polarized laser beams is employed to add the two beamlets. The average power of the combined beam is up to 107.5 W with a combining efficiency of 94.3%. The combined beam has a 1 kHz repetition rate with ${\sim}{120}\;\unicode{x00B5} {\rm s}$∼120µs pulse duration and beam quality ${M^2} = {1.41}$M^2=1.41. The central wavelength with a linewidth of ${\sim}{0.3}\;{\rm GHz}$∼0.3GHz is locked to a sodium ${{\rm D}_{2a}}$D_2a absorption line. To the best of our knowledge, this is a record-high power operating at kilohertz for µs-pulsed solid-state sodium beacon lasers.

A void-free bonding technique was demonstrated for a large slab Nd: YAG crystal with a bonding surface dimension of $\sim{160}\;{\rm mm} \times {70}\;{\rm mm}$∼160mm×70mm. By using the novel fluxless oxide layer removal technology, the indium-oxide barrier problem was resolved. With the help of electrochemical-polished indium solder and a plasma-cleaned heat sink, the solderability of the indium was enhanced; in particular, the contact angle of the solder was improved from 51° to 31°. With the largest-bonding-size slab, a single-slab laser created a maximum output power of 7.3 kW under an absorbed pump power of 12.8 kW, corresponding to an optical to optical efficiency of 57% and a slope conversion of 67.8%. By detecting the wavefront of the interferometer before and after bonding, the RMS of wavefront was ${0.192}\lambda $0.192λ and ${0.434}\lambda $0.434λ ($\lambda = {633}\;{\rm nm}$λ=633nm), respectively. To the best of our knowledge, this is the largest void-free bonding size for a laser slab and the highest output power achieved from a single-slab crystal laser oscillator.

The security of the dynamic heterogeneous redundancy (DHR) architecture relies on the heterogeneity of its executors, which also defines the vulnerability of the mimic system. In order to select executors with reliable and significant dissimilarity as service executors, we propose a DHR executor selection algorithm based on historical credibility and dissimilarity clustering (HCDC), which adds two metrics of executor historical credibility and dissimilarity. First, to maximize the difference between heterogeneous executor pools, clustering is performed based on the dissimilarity of the executor. Second, the executor with the highest historical credibility is selected from the heterogeneous executor pool as the candidate pool. The historical credibility is dynamically updated by the negative feedback control based on the results of the multi-mode adjudicator. Finally, the dynamic scheduling algorithm selects the executors from the candidate pool to form the set of service executors. The simulation results demonstrate that, in comparison to existing methods, the algorithm reduces the attack success rate and average failure rate while increasing system reliability.

Retail business has been rapidly evolving in the past decades with the boom of internet, mobile technologies and most importantly e-commerce. Supply chain management, as a core part of retail business, has also gone through significant changes with new business scenarios and more advanced technologies in both algorithm design and computation power. In this review, we focus on several core components of supply chain management, i.e. vendor management, demand forecasting, inventory management and order fulfillment. We will discuss the key innovations from both academia and industry and highlight the current trend and future challenges.

Non-orthogonal multiple access (NOMA) attracts much attention from industry and academia as it promises more connections. One interesting yet important question is, “What is the number of maximally admissible users in NOMA?” In this letter, a lower bound of admissible user equipment (UE) number is derived, which relates to the spreading factor, the required signal to interference and noise ratio, and the noise power only. Also, the overloading factor, i.e., the normalized admissible UE number, can be presented as 1 $ {+}{\Delta }$ , where ${\Delta }$ denotes the capability of interference tolerance in NOMA. Further, with considering Rayleigh-distributed fading channels, stochastic analysis is used to get a clean expression of the probability of accessing the network successfully in NOMA. Numerical results show the current demodulation reference signal pattern in 5G needs to be enhanced and a lower modulation and coding scheme is more suitable to achieve a higher overloading.

China National Petroleum Corporation collaborated with researchers from the University of California and Tsinghua University to develop software for planning its natural gas pipelines. The work resulted in increased profits of $530 million between 2015 and 2017 and a budget reduction of more than $20 billion in construction costs for the subsequent five years.

The present study, for the first time, was designed to examine the antifibrosis effects of Shenge Yangfei Capsules (SGYF) on bleomycin-induced pulmonary injury and fibrosis in rats.

ObjectiveThere is little evidence that adjuvant therapy after radical surgical resection of hepatocellular carcinoma (HCC) improves recurrence-free survival (RFS) or overall survival (OS). We conducted a multicentre, randomised, controlled, phase IV trial evaluating the benefit of an aqueous extract of Trametes robinophilaMurr (Huaier granule) to address this unmet need.Design and resultsA total of 1044 patients were randomised in 2:1 ratio to receive either Huaier or no further treatment (controls) for a maximum of 96 weeks. The primary endpoint was RFS. Secondary endpoints included OS and tumour extrahepatic recurrence rate (ERR). The Huaier (n=686) and control groups (n=316) had a mean RFS of 75.5 weeks and 68.5 weeks, respectively (HR 0.67; 95% CI 0.55 to 0.81). The difference in the RFS rate between Huaier and control groups was 62.39% and 49.05% (95% CI 6.74 to 19.94; p=0.0001); this led to an OS rate in the Huaier and control groups of 95.19% and 91.46%, respectively (95% CI 0.26 to 7.21; p=0.0207). The tumour ERR between Huaier and control groups was 8.60% and 13.61% (95% CI −12.59 to −2.50; p=0.0018), respectively.ConclusionsThis is the first nationwide multicentre study, involving 39 centres and 1044 patients, to prove the effectiveness of Huaier granule as adjuvant therapy for HCC after curative liver resection. It demonstrated a significant prolongation of RFS and reduced extrahepatic recurrence in Huaier group.Trial registrationNCT01770431; Post-results.

This study evaluated and analyzed the grade of offensive and defensive ability of 12 women's volleyball teams in Rio Olympic Games by the methods of literature review, expert interview and technology statistics. Results: On the offensive side, teams of Serbia, USA, the Netherlands, Brazil and China had the most outstanding offensive capability, their WRSR was high and they were at B level. On the defensive side, team of USA had the best defense, and teams of Seville, Holland, China and USA were at B level. Team of Brazil was less defensive than other teams, was at C level; the WBSR of Serbia was the highest one. The offensive WRSR value, defensive WRSR value, and offensive and defensive WRSR value were significantly related to the final ranking. The Rio Olympic women's volleyball team was divided into 5 levels, and teams of China, Serbia, Holland and USA were at the first level, representing the highest level in the world. The common features of offensive and defensive tactics of high level women's volleyball teams in the Rio Olympics were as follows. The attacking point of the smash was changeable and the route was diversified; the service was very aggressive; block awareness was high and location was accurate; toss was high successful rate and the pass form was flexible; strong team was good at offence and defense, and focused on collaborative combat. [ABSTRACT FROM AUTHOR]

By using the methods of literature review, interview and mathematical statistics, this study collected and analyzed the results of 7 World Cups and World Championships of Freestyle Skiing Aerials in the season of 2016-2017, discussed the strengths and weaknesses of Chinese key athletes of freestyle skiing aerials, explored the working direction and priorities in training, analyzed the world pattern of freestyle skiing aerials and the competitive strength of major opponents. Conclusions: The main opponents of Chinese women's team in 2018 Pyeongchang Winter Olympic Games are from Australia, the United States and Russia, the main opponents of men's team are from Belarus, the United States and Russia; the Chinese Freestyle Skiing Aerials have power balance in men and women teams, and show a certain advantage. This study provided the following suggestions for the preparations. Chinese teams need to deeply analyze the scoring mles and competition rules to comprehensively understand the rule of winning; explore new mode of specific training to effectively improve the athletes' competition ability; strength thought and work style construction to promote both skills and ideals; dialectically understand the relationship between the difficulty and quality of action to improve athletes, competitive strength; conscientiously do a good job of prevention and treatment of athletes, injuries and diseases to effectively avoid non combat self loss; and establish and perfect the security system to constantly improve the level of management and security. [ABSTRACT FROM AUTHOR]

The application of a sodium laser guide star is the key difference between a modern adaptive optics system and traditional adaptive optics system. Especially in system such as multiconjugate adaptive optics, a sodium laser guide star asterism that is formed by several laser guide stars in a certain pattern is required to probe more atmospheric turbulence in different directions. To achieve this, a sodium laser guide star asterism launching platform is required. In this paper, we introduce the sodium laser guide star asterism launching platform built and tested on the 1.8 m telescope of Gaomeigu Observatory. The platform has two functions: one function is to compare the performance of sodium laser guide stars generated by different lasers at the same place, and the other function is to generate a sodium laser guide star asterism with an adjustable shape. The field test results at the beginning of 2021 verified the important role of the platform, which is also the first time that a sodium laser guide star asterism was realized in China.

Background Hypertension complicated with left ventricular hypertrophy (LVH) and diastolic dysfunction is one of the most common risks for heart failure with preserved ejection fraction (HFpEF). This study was designed to evaluate the influences of long-term beta-blocker prescription in these patients.Methods This retrospective analysis included eligible patients diagnosed with hypertension, LVH (left ventricular (LV) mass index >125 g/m2for men and >110 g/m2for women) and suspected diastolic dysfunction (E/E’ ratio between 8 and 15) and without clinical signs or symptoms of heart failure in our hospital medical record database (January 2005–December 2009). A total of eligible 1498 patients were enrolled, of whom 803 received beta-blocker prescription and 695 accepted non-beta-blocker therapy.Results With a median follow-up of 7.2 years, the new-onset symptomatic HFpEF occurred in 48 of 803 patients in the beta-blocker group (6.0%) and 92 of 695 patients in the non-beta-blocker group (13.2%, p< 0.001). Beta-blockers also generated more prominent improvement in diastolic function and LVH. And Cox proportional hazards model revealed that beta-blocker (hazard ratio (HR) 0.327, 95% confidence interval (CI): 0.121–0.540, p= 0.009) or angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker (ACEI/ARB) exposure (HR 0.422, 95% CI: 0.210–0.699, p= 0.015) was associated with a reduced risk of new onset of symptomatic HFpEF, and the elevation of LVMI (HR 1.210, 95% CI: 1.069–1.362, p= 0.040) or E/E’ (HR 1.398, 95% CI: 1.306–1.541, p= 0.032) was associated with a high risk of new onset of symptomatic HFpEF.Conclusions Long-term beta-blocker exposure was associated with protective effects in terms of the incidence of new-onset symptomatic HFpEF, LV diastolic dysfunction and LVH, which might be beneficial for the delay of HFpEF progression.

A 65 W quasi-continuous-wave microsecond-pulse solid-state sodium beacon laser tuned to the sodium D_2a line has been developed with a linewidth of 0.3 GHz, beam quality of M^2=1.38, and pulse width of 120 μs at a repetition rate of 500 Hz by sum-frequency mixing 1319 and 1064 nm diode-pumped Nd:YAG master-oscillator power-amplifier systems. The laser wavelength stability is less than ±0.15  GHz through feedback controlling. The laser spiking due to relaxation oscillations is suppressed by inserting frequency doublers in both 1319 and 1064 nm oscillators. Sodium D_2b re-pumping is accomplished by tuning the frequency of the electro-optic modulator with the right D_2a−D_2b offset. A bright sodium laser guide star with a photon return of 1820  photons/cm^2/s was achieved with the laser system when a 32 W circular polarized beam was projected to the sky during our field test at the Xinglong Observatory.

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ABSTRACTAntiviral drugs do not currently exist for the treatment of enterovirus infections, which are often severe and potentially life-threatening. We conducted high-throughput molecular screening and identified a structurally diverse set of compounds that inhibit the replication of coxsackievirus B3, a commonly encountered enterovirus. These compounds did not interfere with the function of the viral internal ribosome entry site or with the activity of the viral proteases, but they did drastically reduce the synthesis of viral RNA and viral proteins in infected cells. Sequence analysis of compound-resistant mutants suggests that the viral 2C protein is targeted by most of these compounds. These compounds demonstrated antiviral activity against a panel of the most commonly encountered enteroviruses and thus represent potential leads for the development of broad-spectrum anti-enteroviral drugs.

A low-timing-jitter high-power semiconductor saturable absorber mirror mode-locked picosecond (ps) 1063 nm Nd:GdVO_4 master oscillator power amplifier is presented. Using a single-pass Nd:GdVO_4 amplifier, an amplified laser with 21.5 W output power and 8.3 ps pulsewidth was achieved at 250 MHz repetition rate. Employing a servo control, an average RMS timing jitter of ∼222  fs was realized. This laser can be used as a drive laser for photocathode injectors in free-electron lasers.