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Background Although the efficacy of hepatitis B vaccines among hemodialysis patients has been documented, the long-term persistence of immunogenicity in this population remains largely unknown. We explored the long-term persistence of immunogenicity induced by different hepatitis B vaccine regimens in hemodialysis patients. Methods In initial study, we conducted a randomized, multicenter, double-blind, parallel-controlled trial among hemodialysis patients in 13 hospitals in Shanxi Province, China. A total of 352 hemodialysis patients were allocated to receive 3-dose 20 μg (IM20 group) and 3-dose 60 μg (IM60 group) recombinant hepatitis B vaccine at months 0, 1, and 6. Vaccine-induced immune responses were measured at month 7. In this study, the responders (anti-HBs ≥ 10 mIU/mL) were followed up at months 18, 24, 30, 36 and 42, respectively. We used the generalized log-rank test and generalized estimating equations (GEE) to analyze the long-term durability of responses and the kinetics of anti-HBs levels, respectively. Results A total of 284 patients were involved in the extended follow-up period. The duration of vaccine-induced response with 75% of patients maintained protective antibody were 12 months and 18 months in the IM20 group and IM60 group, respectively (P = 0.291). The long-term persistent immunogenicity induced by 3-dose 60 μg was more satisfactory than that by 3-dose 20 μg hepatitis B vaccine in patients with hemodialysis duration ≥ five years (P = 0.023). The peak anti-HBs levels in 100–1000 mIU/mL or ≥ 1000 mIU/mL were more likely to maintain long-term protective antibody compared to anti-HBs levels in 10–100 mIU/mL (P ＜ 0.05). The kinetic profile was similar between the two groups (P = 0.334). Conclusion High-dose 60 μg hepatitis B vaccine could lead a satisfactory long-term durability of immunogenicity among patients with hemodialysis duration of five years or more. Peak anti-HBs level after vaccination was associated with the long-term persistence of immunogenicity.

Metal phosphorus trichalcogenides (MPX3) have attracted extensive attention as promising two-dimensional (2D) layered materials in future electronic and optoelectronic devices. Here, for the first time, few-layer In4/3P2Se6 nanoflakes have been successfully exfoliated from home-made high-quality single crystals. The In4/3P2Se6 crystal belongs to the R3 space group, and possesses a weak van der Waals force between the adjacent layers and a direct bandgap of 1.99 eV. Furthermore, the In4/3P2Se6-based photodetectors show high performances in the visible light region, such as a high responsivity (R) of 4.93 A·W-1, a high external quantum efficiency (EQE) of 1509% and a fast response time, as low as 2.1 ms. In particular, the high detectivity (D) of the devices can reach up to 4.3 × 1013 Jones (light ON/OFF ratio ≈104) under illumination from a 405 nm light at a bias voltage of 1 V, which is favoured by the ultralow dark current (∼100 fA). These excellent performances pave the way for the implementation of In4/3P2Se6 nanoflakes as promising candidates for future optoelectronic detection applications.

There is an emerging need for semiconductors that can be processed at near ambient temperature with high mobility and device performance. Although multiple n-type options have been identified, the development of their p-type counterparts remains limited. Here, we report the realization of tellurium thin films through thermal evaporation at cryogenic temperatures for fabrication of high-performance wafer-scale p-type field-effect transistors. We achieve an effective hole mobility of ~35 cm2 V-1 s-1, on/off current ratio of ~104 and subthreshold swing of 108 mV dec-1 on an 8-nm-thick film. High-performance tellurium p-type field-effect transistors are fabricated on a wide range of substrates including glass and plastic, further demonstrating the broad applicability of this material. Significantly, three-dimensional circuits are demonstrated by integrating multi-layered transistors on a single chip using sequential lithography, deposition and lift-off processes. Finally, various functional logic gates and circuits are demonstrated.

Two-dimensional ferroelectric semiconductors (2DFeSs) have been attracting extensive research attention on account of their unique properties and versatile applications in random-access memory, digital signal processors, and neuromorphic computing. Germanium sulfide (GeS) is predicted as a typical 2DFeS with a large spontaneous polarization of 484 pC m−1. Furthermore, the moderate band gap equivalent to 1.63 eV of GeS provides it with significant potential to create a strong bulk photovoltage in the visible light range. However, the fabrication of chemically stable few-to-monolayer GeS has not been reported so far, owing to the strong interlayer force and high chemical reactivity of the surface. Herein we demonstrate a new method for fabricating high quality, air-stable, ultrathin GeS nanoflakes. The electrical characterization confirms the formation of few-layered GeS with a remarkable in-plane ferroelectric hysteresis, which is forbidden by the inversion symmetry in bulk GeS crystals. After applying a coercive field of about 18.1 kV cm−1, a switchable shift current can also be observed in the polarized GeS nanoflakes under light irradiation. To further enhance the photoresponsivity, few-layered InSe was transferred onto the GeS nanoflakes to form van der Waals ferroelectric diodes. The interfacial perturbation breaking the inversion symmetry results in the enhancement of robust dipoles in the GeS side along the interface, which can be tuned by the in-plane electric field. Overall, this work opens the door for exploring the low-dimensional ferroelectric memory and energy conversion applications based on 2D GeS nanoflakes and provides a deeper understanding of the photovoltaic mechanism with in-plane 2D ferroelectric diodes.

High performance photodetectors based on van der Waals heterostructures (vdWHs) are crucial to developing micro-nano-optoelectronic devices. However, reports show that it is difficult to balance fast response and high sensitivity. In this work, we design a photovoltaic field-effect photodiode (PVFED) based on the WSe2/MoS2/WSe2 double vdWHs, where the photovoltage that originated from one vdWH modulates the optoelectronic characteristics of another vdWH. The proposed photodiode exhibits an excellent self-powered ability with a high responsivity of 715 mA·W-1 and fast response time of 45 μs. This work demonstrates an efficient method that optimizes the photoelectric performance of vdWH by introducing the photovoltaic field effect.

Purpose. To compare the clinical outcomes of echelette extended range of vision (ERV) and diffractive bifocal intraocular lenses (IOLs). Methods. This is a prospective, consecutive, nonrandomized clinical trial. Seventy-three eligible patients (109 eyes) received the implantation of echelette ERV IOL (Tecnis Symfony ZXR00) or diffractive bifocal IOL (Tecnis ZMB00). 1 week, 1 month, and 3 months after surgery, visual acuities at different distances were examined. At 3 months, defocus curves, contrast sensitivities (CSs) with and without glare, optic path difference (OPD) scans, and questionnaires were evaluated. Regression analyses were applied to discover influence factors on postoperative vision. Results. ZXR00 showed better distance (P<0.05) and intermediate (P<0.001) visual acuities, while ZMB00 was better at distance-corrected near visual acuity (P<0.001). Multivariate analyses indicated that worse intermediate (P<0.001) and near vision (P=0.013) of ZMB00 might occur in patients with longer axial length. ZXR00 demonstrated smoother defocus curve and higher CSs. Superior modulation transfer function (MTF) and higher Strehl ratio (P<0.05) were shown in ZXR00. In questionnaire evaluation, ZXR00 received better outcomes in self-reported vision, Visual Function-14 (VF-14) questionnaire, Quality of Vision (QoV) questionnaire, satisfaction, and recommendation grades. Spectacle dependence did not differ between ZXR00 and ZMB00 statistically. Conclusion. ZXR00 proved to be remarkable in distance and intermediate vision, defocus curve smoothness, CSs, and visual comfort, while ZMB00 achieved better near vision. ZXR00 may attain better near vision if postoperative SE remains slightly negative. Patients with relatively longer axial length might receive less favorable intermediate and near vision after ZMB00 implantation. This trial is registered with ChiCTR-ONC-17011119.

Digital PCR is a powerful method for absolute nucleic acid quantification with unprecedented accuracy and precision. To promote the wider use and application of digital PCR, several major challenges still exist, including reduction of cost, integration of the instrumental platform, and simplification of operations. This paper describes a reusable microfluidic device that generates nanoliter droplet arrays based on step emulsification for the on-chip multiplex digital PCR of eight samples simultaneously. The device contains two glass plates that can be quickly assembled with prefilled mineral oil. Droplets are simply generated through the arrays of step emulsification nozzles driven by a single pressure controller and are self-assembled into monolayer droplet arrays in U-shaped chambers. The use of mineral oil eliminates bubble generation; thus, no overpressure is required during thermocycling. Moreover, the device can be reused many times after disassembly and a brief cleaning procedure, which significantly reduces the cost of the device per dPCR assays. The device was able to detect template DNA at concentrations as low as 10 copies/μL with a dynamic range of approximately 4 logs. We applied this device in the quantitative assessment of HER2 copy number variation, which is important for targeted therapy and prognosis of breast cancer. The performance was validated by 16 clinical samples, obtaining similar results to commercial digital PCR. We envision that this low-cost, reusable, and user-friendly device can be broadly used in various applications.

As a new hopeful two-dimensional (2D) layered semiconductor material in nanoscaled electronic devices, 2D InSe nanosheet has been constructed successfully and identified to be a native n-type semiconductor. In this work, we provide theoretical studies that Ag substituting In atom can generate p-type carriers in the InSe monolayer, and its formation energy is lower under Se-rich condition, which shows that the p-type Ag-doped InSe system can be fabricated experimentally. More importantly, compressive strain makes the impurity states move toward the valence band edge, and thus p-type conducting characteristics are further improved. These findings show that for native n-type 2D InSe nanosheet, the properties of p-type carriers and band gap can be tuned, which will be useful to design 2D InSe material-based electronic devices in the future.

Objectives: Either motor training or repetitive transcranial magnetic stimulation (rTMS) could modulate the neural plasticity after stroke. Therefore, synchronizing the two interventions may optimize the efficiency of recovery. In the present study, we aim to investigate the effect of rTMS along with hand grip training on the neurobehavioral and hand functional recovery in one cohort of subacute stroke patients.Methods: Thirty-nine stroke patients were enrolled in a single-center, single-blinded, randomized clinical trial. We tested different intervention effects of rTMS and hand grip training (group A), rTMS alone (group B), and hand grip training alone (group C). For the rTMS-treated groups, patients received 10 consecutive sessions of 5-Hz stimulation over the affected hemisphere with 750 pulses. Jebsen–Taylor Hand Function Test (JTHFT), Fugl-Meyer assessment of upper extremity (FMA-UE), grip strength, modified Barthel index (mBI), and ipsilesional motor evoked potential (iMEP) latency were assessed and compared across the groups.Results: We found that only rTMS along with hand grip training group all improved in JTHFT, FMA-UE, grip strength, and mBI (p ≤ 0.01) compared with the baseline among the three groups. Furthermore, this study demonstrated that rTMS plus hand grip training had much better results in improvement of neurobehavioral outcomes compared to the rTMS alone- and hand grip training alone-treated patients (p < 0.05). However, no significant differences were detected in neurophysiologic outcome between intra-groups and inter-groups (p > 0.05).Conclusion: These proof-of-concept results suggested that rTMS alone with hand grip training was a unique approach to promote hand functional recovery in stroke patients. It provided important information to design a large-scale multi-center clinical trial to further demonstrate the efficiency of the combination of central and peripheral stimulation.Clinical Trial Registration:http://www.chictr.org.cn (#ChiCTR1900023443).

The non/hypo-response rate of the hepatitis B vaccine among hemodialysis (HD) patients is still high, it is of great significance to explore the influencing factors and their relationships. To study the related factors and their relationships using logistic regression model and Chi-squared Automatic Interaction Detection (CHAID) decision tree model. A randomized controlled trial was conducted between February 2014 and May 2015 in China. HD patients being serologically negative for HBsAg and anti-HBs were randomly assigned to receive three intramuscular injections of the standard dose (20 µg) or high dose (60 µg) of recombinant hepatitis B vaccine at months 0, 1, and 6. Those with anti-HBs concentrations 4 times per 2 weeks) (OR = 1.918, 95%CI: 1.015–3.626) had a significant risk of non/hypo-response. While the CHAID analysis showed that gender, dose, and dialysis frequency were influencing factors of non/hypo-response, and gender is most important. The interaction between gender and dialysis frequency had the greatest effect on immunization, and followed by the interaction between dialysis frequency and vaccine dose. Taken together, gender, dose and dialysis frequency were influencing factors of hepatitis B vaccine in HD patients.

Background: Cognitive load plays a vital role in human cognitive activities, and effective measurement and intervention of cognitive load can improve learners' learning effect. As a new method of measurement, physiological measurement can show the neural mechanism of cognitive overload. MRI and EEG, as the first physiological measurement methods, have made great contributions to the related research of cognition，but they have unavoidable flaws to a certain extent. As a new physiological measurement method in recent years, fNIRS can effectively avoid the influence of the above equipment on the experiment. This study uses fNIRS to measure cognitive load with the N-back classic paradigm, aiming to explore whether the sensitivity of the prefrontal area to the task and the difficulty of the task will affect the cognitive load of the individual. Results: Through the GLM model to concretely analyze the brain activation area and use repeated measurement analysis of variance to compare behavioral data, it can be concluded that the prefrontal cortex can be effectively activated under the stimulation of work tasks. In a certain range, the prefrontal lobe activation becomes more obvious with the increase of cognitive load, but when the cognitive load exceeds the maximum limit that the prefrontal lobe can handle, the prefrontal lobe will be in a negative activation state.Conclusion: These results suggest when the task load is appropriate, the PFC can be most effectively activated for working memory processing. Therefore, learners should be analyzed in teaching activities so as to choose appropriate teaching content to ensure the maximization of teaching effect.

Metabolic dysfunction is becoming a predominant risk for the development of many comorbidities. Ischemic heart disease (IHD) still imposes the highest disease burden among all cardiovascular diseases worldwide. However, the contributions of metabolic risk factors to IHD over time have not been fully characterized. Here, we analyzed the global disease burden of IHD and 15 associated general risk factors from 1990 to 2019 by applying the methodology framework of the Global Burden of Disease Study. We found that the global death cases due to IHD increased steadily during that time frame, while the mortality rate gradually declined. Notably, metabolic risk factors have become the leading driver of IHD, which also largely contributed to the majority of IHD-related deaths shifting from developed countries to developing countries. These findings suggest an urgent need to implement effective measures to control metabolic risk factors to prevent further increases in IHD-related deaths.

The optimal configuration method of energy storage considering the impact of optimal operation of energy storage on economic income is an important foundation for commercial investment in energy storage. This paper proposes an optimal configuration model of user-side energy storage aiming at the net present value of the entire life cycle of the energy storage system, and comprehensively considering the income of user peak-valley arbitrage and the reduction of demand electricity charges caused by two-part tariff. Considering the problem that the model cannot be solved directly since the operating variables and planning variables in the model are coupled with each other and the model contains exponential variables, this paper proposes the method based on the feasible region discretization and variable iterative correction to reduce the difficulty of solving the original model. Finally, the optimized results of the user-side energy storage configuration are calculated with data from two typical areas of Beijing and Shanghai, which verified the validity and stability of the model.

Background To develop a sensitive and clinically applicable risk assessment tool identifying coronavirus disease 2019 (COVID-19) patients with a high risk of mortality at hospital admission. This model would assist frontline clinicians in optimizing medical treatment with limited resources. Methods 6415 patients from seven hospitals in Wuhan city were assigned to the training and testing cohorts. A total of 6351 patients from another three hospitals in Wuhan, 2169 patients from outside of Wuhan, and 553 patients from Milan, Italy were assigned to three independent validation cohorts. A total of 64 candidate clinical variables at hospital admission were analyzed by random forest and least absolute shrinkage and selection operator (LASSO) analyses. Results Eight factors, namely, Oxygen saturation, blood Urea nitrogen, Respiratory rate, admission before the date the national Maximum number of daily new cases was reached, Age, Procalcitonin, C-reactive protein (CRP), and absolute Neutrophil counts, were identified as having significant associations with mortality in COVID-19 patients. A composite score based on these eight risk factors, termed the OURMAPCN-score, predicted the risk of mortality among the COVID-19 patients, with a C-statistic of 0.92 (95% confidence interval [CI] 0.90–0.93). The hazard ratio for all-cause mortality between patients with OURMAPCN-score >11 compared with those with scores ≤ 11 was 18.18 (95% CI 13.93–23.71; p

Background To develop a sensitive risk score predicting the risk of mortality in patients with coronavirus disease 2019 (COVID-19) using complete blood count (CBC). Methods We performed a retrospective cohort study from a total of 13,138 inpatients with COVID-19 in Hubei, China, and Milan, Italy. Among them, 9,810 patients with ≥2 CBC records from Hubei were assigned to the training cohort. CBC parameters were analyzed as potential predictors for all-cause mortality and were selected by the generalized linear mixed model (GLMM). Findings Five risk factors were derived to construct a composite score (PAWNN score) using the Cox regression model, including platelet counts, age, white blood cell counts, neutrophil counts, and neutrophil:lymphocyte ratio. The PAWNN score showed good accuracy for predicting mortality in 10-fold cross-validation (AUROCs 0.92–0.93) and subsets with different quartile intervals of follow-up and preexisting diseases. The performance of the score was further validated in 2,949 patients with only 1 CBC record from the Hubei cohort (AUROC 0.97) and 227 patients from the Italian cohort (AUROC 0.80). The latent Markov model (LMM) demonstrated that the PAWNN score has good prediction power for transition probabilities between different latent conditions. Conclusions The PAWNN score is a simple and accurate risk assessment tool that can predict the mortality for COVID-19 patients during their entire hospitalization. This tool can assist clinicians in prioritizing medical treatment of COVID-19 patients. Funding This work was supported by National Key R&D Program of China (2016YFF0101504, 2016YFF0101505, 2020YFC2004702, 2020YFC0845500), the Key R&D Program of Guangdong Province (2020B1111330003), and the medical flight plan of Wuhan University (TFJH2018006)., Context and significance Researchers from Wuhan, China developed a complete blood count-based risk score (PAWNN score) that can predict mortality during the entire course of hospitalization in a large cohort with 13,138 COVID-19 patients. This risk score was validated in two independent cohorts from China and Italy and in a longitudinal model. The model can serve as a valuable tool for physicians with very limited medical resources to properly monitor and stratify COVID-19 patients and to reduce mortality., Graphical Abstract, Highlights The blood count-based PAWNN score can accurately predict mortality risk of COVID-19 PAWNN can properly stratify COVID-19 patients with limited medical resources, Liu et al. developed and validated a complete blood count-based score (PAWNN) that can predict mortality during the entire course of hospitalization in a cohort of 13,138 COVID-19 patients. The model can serve as a valuable tool to properly monitor and stratify COVID-19 patients with very limited medical resources.

In December 2019, SARS-CoV-2 was first detected in the samples obtained from three adult patients who suffered from an unknown viral pneumonia in Wuhan (Li et al. 2020). This unknown viral pneumonia is further named as coronavirus disease 2019 (COVID-19) by the World Health Organization. To date, the number of new COVID-19 cases has continued to skyrocket and the impact of SARS-CoV-2 on humans is far greater than any pathogen of this century in both breadth and depth. Previous studies have shown that adults with COVID-19 have symptoms of fever, dry cough, dyspnea, fatigue and lymphocytopenia. Moreover, COVID-19 is more likely to cause death in the elderly, especially those with chronic comorbidities (Huang et al. 2020). In Wuhan, more than 50, 000 COVID-19 cases have been confirmed, including over 780 pediatric patients, and only one child death case (Lu et al. 2020). Although the number of children cases was far fewer than that of adults, COVID-19 might endanger children's health and the information on children remains limited, especially in serological study. In the retrospective study, the investigators analyzed the epidemiological, clinical and serological characteristics of children with COVID-19 in Wuhan in the early stages of the outbreak, which might provide theoretical and practical help in controlling COVID-19 and similar emerging infectious diseases in the future.

A high proportion of renewable energy connected to the power grid has caused power quality problems. Voltage-sensitive loads are extremely susceptible to voltage fluctuations, causing power system safety issues and economic losses. Considering the uncertainty factor and the time-varying characteristic, a linearized random ZIP model (constant impedance (Z), constant current (I), and constant power (P)) with time-varying characteristics was proposed. In order to improve the voltage quality of the voltage-sensitive loads in the day-here stage in an active distribution network (ADN), a linearized two-stage active and reactive power coordinated stochastic optimization model was established. The day-ahead active and reactive power coordination optimization was to smooth the large voltage fluctuation and develop a reserve plan to eliminate the unbalanced power caused by the prediction error in the day-here optimization. In the day-here real-time redispatch, the voltage was further improved by the continuous reactive power compensation device. Finally, the simulation results on the IEEE-33 bus system showed that the control strategy could better eliminate the unbalanced power caused by the prediction error and obviously improve the voltage of sensitive loads in the real-time stage on the premise of maintaining economic optimality.

Supplemental Digital Content is available in the text., The prognostic power of circulating cardiac biomarkers, their utility, and pattern of release in coronavirus disease 2019 (COVID-19) patients have not been clearly defined. In this multicentered retrospective study, we enrolled 3219 patients with diagnosed COVID-19 admitted to 9 hospitals from December 31, 2019, to March 4, 2020, to estimate the associations and prognostic power of circulating cardiac injury markers with the poor outcomes of COVID-19. In the mixed-effects Cox model, after adjusting for age, sex, and comorbidities, the adjusted hazard ratio of 28-day mortality for high-sensitivity cardiac troponin I was 7.12 ([95% CI, 4.60–11.03] P

During the spacecraft assembly process, cables need to be frequently plugged in. Since the vacant electrical connectors are all wrapped in anti-static red cloth bags, the red cloth bags need to be opened one by one during the operation to find the electrical connectors to be operated. As a result, the labor intensity of electric fitting personnel has been increased. And repeated operations are performed beside the satellite increased operational risks such as bumps and mis plugging. Based on the work practice, this article puts forward a suggestion to increase the number and color of the electrical connector at the end of the cable branch and uses a certain type of electrical equipment to compare the work efficiency. This suggestion has a certain meaning to improve work efficiency of the final assembly and lower the risk of operation in electric fitting.

Line fault is the most important factor which affects the reliability of power supply in distribution network. After failure, it is needed to find fault cause quickly and accurately, which will eliminate potential safety hazard for grid operation from the source and reduce fault probability effectively. At present, analysis for fault cause always depends on human experience, which is lack of scientific quantitative basis and poor in time effectiveness. This paper mines out the gradational structure and space-lime distribution law of fault cause from fault historical records and proposes a line-fault cause analysis method based on decision-making tree. For the decision tree analysis, according to line type, time segment, territorial area, external environment and cause analysis level related with a fault, a modeling method based on machine learning for larger-/subcategory fault cause analysis is proposed and then a multi-level model library for line fault cause analysis is established. Based on fault historical records, the proposed method builds models offline and makes decisions on-line, which improves analysis speed. And the hierarchical analysis process of decision-making tree makes fault cause conclusion more detailed and accurate. Finally, a case is given to illustrate application of the method in detail.

The deployable thermal radiator is a thermal energy radiator which is gathered on the side wall of the spacecraft during launch and is deployed after orbiting. It has been widely used in foreign satellite platforms. In this paper, based on the requirements of a spacecraft for the first time to install a deployable thermal radiator, a full analysis of the installation conditions is come up with industrial robot-assisted assembly technology. A series of toolings is designed. A large-scale component installing method is proposed, which can effectively ensure the product installation reliability and greatly improve the overall assembly efficiency of the spacecraft assembly.

During the "13th Five-Year Plan" period, distributed generation develops rapidly, so it is urgent to study and establish an operation management system that adapts to high penetration distributed generation integration. Based on the analysis of typical national distributed generation operation management practices and experience, this paper proposes an operational management system adapted to China’s high penetration Distributed generation integration considering the current situation of distributed generation operation management and the issues that need to be focused on. The relevant measures and suggestions are conducive to promoting the coordinated development of distributed generation and power grid.

This paper is based on the requirements of a spacecraft for the first time to install a deployable thermal radiator. According to the structural characteristics of the deployable radiator and the assembly technology of industrial robot, this paper analyzes and proves the installation conditions of the deployable radiator comprehensively, and puts forward a large deployable flexible component installation method based on human-computer cooperation mode, which effectively guarantees the reliability of product installation, greatly improves the overall assembly efficiency and reliability of spacecraft assembly.

Summary Statins are lipid-lowering therapeutics with favorable anti-inflammatory profiles and have been proposed as an adjunct therapy for COVID-19. However, statins may increase the risk of SARS-CoV-2 viral entry by inducing ACE2 expression. Here, we performed a retrospective study on 13,981 patients with COVID-19 in Hubei Province, China, among which 1,219 received statins. Based on a mixed-effect Cox model after propensity score-matching, we found that the risk for 28-day all-cause mortality was 5.2% and 9.4% in the matched statin and non-statin groups, respectively, with an adjusted hazard ratio of 0.58. The statin use-associated lower risk of mortality was also observed in the Cox time-varying model and marginal structural model analysis. These results give support for the completion of ongoing prospective studies and randomized controlled trials involving statin treatment for COVID-19, which are needed to further validate the utility of this class of drugs to combat the mortality of this pandemic., Graphical Abstract, Highlights • Statin treatment among 13,981 patients with COVID-19 was retrospectively studied • Statin use in this cohort was associated with a lower risk of all-cause mortality • Adding an ACE inhibitor or an ARB did not affect statin-associated outcome in the cohort • The benefit of statins among this cohort may be due to immunomodulatory benefits, Statins have anti-inflammatory benefits and were suggested as an adjunct therapy for COVID-19. But statins may increase the expression of ACE2, the receptor for SARS-CoV-2. Here, Zhang et al. retrospectively analyzed 13,981 COVID-19 cases and found that in-hospital statin use is associated with a lower risk of all-cause mortality.

Contact reed and contact subassembly are used in kinds of mechanical inertial apparatus, and they are is the media between electric signal and mechanical movement. In this paper, in accordance with the problem in the process of producing, through the experiment and analysis, the cause is found and processing technique to solving the problem is presented. The technique can be used in the producing process and can increase the passing rate of the gyroscope. The technique can play an important role in improving the overall assembly quality of the instrument and the ex-factory pass rate, effectively improving the reliability of spacecraft assembly.

PURPOSE To compare the visual outcomes and optical quality of 2 presbyopia-correcting intraocular lenses (IOLs) with those of a monofocal IOL. SETTINGS Eye Center, the Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, Zhejiang, China. DESIGN Prospective cohort study. METHODS The study included patients who had cataract surgery and were implanted with a Tecnis Symfony Extended Range of Vision (EROV) IOL (ZXR00), a zonal refractive multifocal IOL (Lentis Comfort LS-313 MF15), or a monofocal IOL (Lentis L-313). Postoperative examinations took place at 1 week, 1 month, and 3 months and included visual acuity at far, intermediate, and near distances, defocus curves, contrast sensitivity, wavefront aberrations, and modulation transfer function (MTF). Patients completed the Visual Function Index questionnaire (VF-14), the Quality of Vision questionnaire (QoV), and a visual quality self-evaluation. RESULTS One hundred thirteen patients were enrolled. The EROV and multifocal IOLs achieved a significantly better range of intermediate vergences (P < .05), better distance-corrected intermediate visual acuity (P ≤ .001), higher VF-14 (P < .05) and visual quality self-evaluation scores (P < .05) than the monofocal IOL, but there were no significant differences between the 2 presbyopia-correcting IOLs. The EROV provided lower total wavefront aberrations and better MTF than the multifocal and the monofocal IOLs (P < .05) but demonstrated a worse QoV score (P < .05), especially for severity of halo (P < .01) and starburst (P < .05) symptoms. CONCLUSIONS Both the Tecnis Symfony ZXR00 and the Lentis Comfort LS-313 MF15 offered excellent visual restoration and stable distance and intermediate visual acuity, good subjective visual function, and good contrast sensitivity. The EROV IOL provided better objective optical quality and more prominent dysphotopsia symptoms than the multifocal IOL.

ZnO nanorods were grown on ITO substrate by CBD method. The XRD and SEM show that nanorods with hexagonal column structure were uniformly distributed. Then the optical properties of NRs were investigated. The transmittance spectrum shows a sharp absorption edge in the UV region. The reflection spectrum has a certain oscillation frequency, so the thickness of film can be obtained by the principle of light interference. The PL spectrum shows a UV emission peak at about 380 nm and a broad green emission centered at around 550 nm. By readily adjusting the preparation parameters, the green emission was very weak.

This paper studies the energy management problem in data centers. As the most energy-consuming sub-systems, server and cooling have been considered as the key of energy saving for data center. However, due to the fact that servers are not directly connected to cooling devices, it is not trivial to optimize them jointly. In this paper, we formulate the joint server and cooling energy management problem and analyze its challenges, and design a Learning-based Energy management Scheme (LEES) to solve the joint energy management problem. Firstly, machine learning methods are investigated in the cooling power modeling and cabinet temperature modeling. Based on the models, a simple yet efficient energy management scheme is proposed to find an optimized configuration of server load distribution, server status and air supply temperature setting for the data center to reduce the total energy consumption. Extensive simulation results demonstrate that our method is able to reduce the total energy consumption of data centers significantly.

Two-dimensional (2D) materials, particularly black phosphorus (bP), have demonstrated themselves to be excellent candidates for high-performance infrared photodetectors and transistors. However, high-quality bP can be obtained only via mechanical exfoliation from high-temperature- and high-pressure-grown bulk crystals and degrades rapidly when exposed to ambient conditions. Here, we report solution-synthesized and air-stable quasi-2D tellurium (Te) nanoflakes for short-wave infrared (SWIR) photodetectors. We perform comprehensive optical characterization via polarization-resolved transmission and reflection measurements and report the absorbance and complex refractive index of Te crystals. It is found that this material is an indirect semiconductor with a band gap of 0.31 eV. From temperature-dependent electrical measurements, we confirm this band-gap value and find that 12 nm thick Te nanoflakes show high hole mobilities of 450 and 1430 cm2 V-1 s-1 at 300 and 77 K, respectively. Finally, we demonstrate that despite its indirect band gap, Te can be utilized for high-performance SWIR photodetectors by employing optical cavity substrates consisting of Au/Al2O3 to dramatically increase the absorption in the semiconductor. By changing the thickness of the Al2O3 cavity, the peak responsivity of Te photoconductors can be tuned from 1.4 μm (13 A/W) to 2.4 μm (8 A/W) with a cutoff wavelength of 3.4 μm, fully capturing the SWIR band. An optimized room-temperature specific detectivity ( D*) of 2 × 109 cm Hz1/2 W-1 is obtained at a wavelength of 1.7 μm.

Production scheduling problems are typically combinational optimization problems named bases on the processing routes of jobs on different machines. In this paper, the flexible job shop scheduling problem aimed to minimize the maximum completion times of operations or makespan is considered. To solve such an NP-hard problem, variable neighborhood search (VNS) based on genetic algorithm is proposed to enhance the search ability and to balance the intensification and diversification. VNS algorithm has shown excellent capability of local search with systematic neighborhood search structures. External library is improved to save the optimal or near optimal solutions during the iterative process, and when the objective value of the optimal solutions are the same, the scheduling Gantt charts need to be considered. To evaluate the performance of our proposed algorithm, benchmark instances in different sizes are optimized. Consequently, the computational results and comparisons illustrate that the proposed algorithm is efficiency and effectiveness.

This paper presents a novel distributed secondary control method for both voltage and frequency regulation in islanded microgrids. Firstly, the large-signal dynamic model of inverter-interfaced distributed generation (DG) is formulated in the form of a multi-input multi-output nonlinear system, which can be converted to a partly linear one using input–output feedback linearization. Then, the linear-distributed model predictive controller is designated in each DG to realize the secondary voltage control by incorporating the forecasted behaviors of the local and neighboring DG units. Through the receding optimization index of every update process, the implementation of optimal control action accelerates the convergence rate for voltage magnitudes to the reference value. Following, after transforming the nonlinear DG dynamics into a first-order linear system, a distributed proportional integral algorithm is introduced in the frequency restoration while maintaining the accurate active power sharing. Our approach utilizes the distributed architecture, which indicates superior reliability and flexibility compared to the centralized manner; moreover, it can accommodate diverse uncertainties in communication links, model parameters, and time delays. Simulation results are provided to verify the effectiveness of the proposed control methodology.

A room temperature bonding method was developed in this study to bond vertical allied carbon nanotubes (CNTs) onto gold surface within 5 seconds, and the contact electrical resistance between the CNTs and metal surface was reduced by up to 99%. Unlike traditional thermocompression bonding method, the non-contact induction selective heating occurred at CNT/metal interface, avoiding high temperature and pressure applied on the device. In particular, the atomic study indicated that surface charges induced by the induction heating could improve the wetting between metal atoms and the CNT surface. In addition, the contact configure modification effectively facilitated the surface melting due to increased anharmonicity at the interface. As a result, the welding occurred at much lower temperature than the metal melting point. This behavior provides more material choices for targeting metallic surface rather than using metals with excellent wetting properties to the carbon nanotube. Also, the debonding process also showed that the bonding strength was higher than the tensile strength of CNT itself. The process is promising for large-scale and wafer-level CNT-based devices and thermal interface material assembly.

An important part of the low-frequency cable network spacecraft, in order to improve the efficiency of the spacecraft’s low-frequency cable network assembly process, according to the characteristics of the spacecraft cable network, based on the three-dimensional digital design of the spacecraft cable network, the spacecraft based on the three-dimensional model. The design and optimization of the cable network final assembly, a digital cable network final assembly was proposed to achieve the purpose of improving the efficiency and reliability of the cable network final assembly.

ZnO nanorods consisted of oriented aligned elongated-nanoparticles along the [0001] direction were readily prepared with tunable aspect ratios by a facile solvothermal method. An oriented-attachment growth mechanism was proposed based on time-dependent trails and first principle density function theory calculation. Control experiments indicated that the reaction medium played important roles to influence the oriented-attachment process and the aspect ratio could be tuned from ∼4.6 to ∼16.0 by simply altering the precursor dosages. The as-prepared ZnO nanorods were applied as photoanode materials in quantum-dot sensitized solar cells. The large pore size in the film structure and rough surface of the nanorod could enhance the quantum dots loading amounts and light scattering effect. In addition, the orderly aligned primary ENPs minimized the grain boundaries for suppressed recombination and provided a direct pathway for increased electron diffusion length. Meanwhile, the enhanced film hydrophilicity facilitated the electrolyte penetration and the regeneration of oxidized sensitizers. Therefore, a high power conversion efficiency of ∼4.83% was demonstrated, indicating substantial improvement compared with that of traditional nanoparticle based device (∼3.54%).

CdSe and CdS nanoparticles (NPs) are type I II-VI semiconductor materials with excellent optical properties. Usually various shapes of these NPs show a strong emission only from a CdSe or CdS single domain, while the emission from a CdSe core combined with a CdS shell is effectively suppressed due to the ultrafast hole relaxation from the CdS shell into the CdSe core. Therefore, the design and synthesis of heteronanostructures based on CdSe or CdS is of paramount importance in designing the ways of integrating these useful semiconductor materials into complex hybrid structures. Here we demonstrate the ligand-combination inducing growth method to prepare anisotropic core-shell (semiconductor-semiconductor) heteronanostructures, as well as anisotropic Au-semiconductor heteronanostructures. The NPs' anisotropic shape was confirmed by tilting a grid in TEM and their elemental composition was ascertained using EDX mapping in STEM mode. Furthermore, the photoluminescence excitation spectra were studied showing potential applications based on their unique optical properties. We believe that the mechanism investigation, the synthetic control, the obtained novel hybrid nanostructures and their optical properties will open doors to future studies on heterostructures based on semiconductors.

2D van der Waals heterostructures (vdWHs) offer tremendous opportunities in designing multifunctional electronic devices. Due to the ultrathin nature of 2D materials, the gate‐induced change in charge density makes amplitude control possible, creating a new programmable unilateral rectifier. The study of 2D vdWHs‐based reversible unilateral rectifier is lacking, although it can give rise to a new degree of freedom for modulating the output state. Here, a InSe/GeSe vdWH‐FET is constructed as a gate‐controllable half wave rectifier. The device exhibits stepless adjustment from forward to backward rectifying performance, leading to multiple operation states of output level. Near‐broken band alignment in the InSe/GeSe vdWH‐FET is a crucial feature for high‐performance reversible rectifier, which is shown to have backward and forward rectification ratio of 1:38 and 963:1, respectively. Being further explored as a new bridge rectifier, the InSe/GeSe device has great potential in future gate‐controllable alternating current/direct current convertor. These results indicate that 2D vdWHs with near‐broken band alignment can offer a pathway to simplify the commutating circuit and regulating speed circuit., A gate‐induced reversible AC/DC convertor is realized based on InSe/GeSe heterojunction with near‐broken band alignment. The device exhibits backward and forward rectification ratio of 1:38 and 963:1, respectively. A bridge rectifier based on the InSe/GeSe vdWHs is also proposed to simplify the commutating circuit and regulating speed circuit.

The rapidly increasing penetration of distributed generations (DGs) brings new challenges to the planning and operation of distribution networks. It is of great significance to assess the capacity of distribution networks to accommodate DGs. In this paper, a mixed-integer linear programming (MILP) model is proposed for the hosting capacity (HC) assessment of distribution networks. The employment of the linear formulations can ensure that the obtained solution is near global optimal. In the proposed model, the coordinated optimal operation of on-load tap changer (OLTC), voltage regulator, switchable capacitor bank (SCB) and static VAr compensator (SVC) is incorporated. Moreover, the voltage-independent characteristic of loads is also considered. The simulation conducted on the IEEE 33-bus system tests the validity and accuracy of the proposed method.

To improve the safe level of operation and security guarantee for distribution network. This paper proposes a risk assessment method based on cloud prediction model for distribution network. First, the cloud theory is used in distribution network main equipment failure prediction to build prediction rule based on cloud generator. On the basis of the prediction rule, a cloud-based distribution network main equipment failure rate prediction model is built. Then, failure rate and power outage user-hours of load were calculated based on distribution network main equipment failure rate and net topology with minimum path method. The assessment method could be used to estimate the risk of distribution network in order to scan the weakness in distribution operation. Finally, the test results of IEEE-RBTS BUS6 indicate the failure rate, failure time, risk of the load point can be calculated. The results demonstrate the effectiveness of the proposed method.

With the large-scale access of distributed generation in distribution network, operation control of distribution network faces new challenges. Active distribution network is not to distribute electric energy passively, but to achieve coordinated optimization of source-network-load-storage through active management. Considering different types of distributed generation such as wind power generation, photovoltaic power generation and so on, energy storage devices and flexible loads in active distribution network management, a day-ahead optimization model of active distribution network is established. Taking the day-ahead 24 hours active power output of the distributed generation as the optimization variable, and the minimum operating cost of electric power company as the objective function, the model can realize the maximum consumption of distributed generation and the economical and efficient operation of distribution network. The model is solved by means of adaptive particle swarm algorithm and verified by a modified IEEE 33-node distribution network.

With the access of distributed generation (DG), the structure of distribution network will be changed. Due to intermittent and randomness of the output of DG, it will bring risk to distribution system. In order to realize risk quantitative assessment of distribution network with DG, the outage model of DG and other component of distribution network are built firstly. Second, Latin hypercube sampling method which has smaller variance and faster convergence is proposed to sample and sort the system states. Then a risk assessment process with island isolation of distribution network with DG is proposed. According to the sampling result, the risk indexes are calculated and the risk level classification criteria is proposed in the paper. Finally, the rationality and effectiveness of blackout risk assessment method is verified with IEEE 39-bus distribution network. The simulation results show that the proposed method has smaller variance and faster convergence.

Detecting accurate concentrations of gas in environments with dynamically changing relative humidity conditions has been a challenge in gas sensing technology. We report a method to eliminate effects of humidity response in chemical-sensitive field-effect transistors using microheaters. Using a hydrogen gas sensor with Pt/FOTS active material as a test case, we demonstrate that a sensor response of 3844% to a relative humidity change of 50 to 90% at 25 °C can be reduced to a negligible response of 11.6% by utilizing microheaters. We also show the advantage of this technique in maintaining the same sensitivity in changing ambient temperatures and its application to the nitrogen dioxide gas sensors.

To meet the new demand of extensive interconnection, open and interactive, complementation and sharing, clean and efficient utilisation of various energy resources, the energy−Internet distribution network (EIDN) will lead the future development direction of the AC/DC distribution network. Firstly, the basic connotation and the technical features of EIDN are presented. Secondly, the structural characteristics of EIDN are analysed further. Moreover, a new structural model of EIDN is proposed in the AC/DC distribution network. Then the study proposes a method which can establish the new EIDN structural model. Finally, the application of the proposed EIDN structural model is simulated. The simulation results show that compared with the traditional network structural model, the new EIDN structural model can not only realise optimal allocation and connection sharing of various energy resources but also greatly enlarge the maximum allowable penetration of distributed energy resources and keep energy utilisation effective, secure, and sustainable. Therefore, it can have reference significance to the development of the future AC/DC distribution network

Objective: To investigate the effects of low frequency transcranial magnetic stimulation (LF-rTMS) combined with motor imagery (MI) on upper limb motor function during stroke rehabilitation.Background: Hemiplegic upper extremity activity obstacle is a common movement disorder after stroke. Compared with a single intervention, sequential protocol or combination of several techniques has been proven to be better for alleviating motor function disorder. Non-invasive neuromodulation techniques such as repetitive transcranial magnetic stimulation (rTMS) and motor imagery (MI) have been verified to augment the efficacy of rehabilitation.Methods:Participants were randomly assigned to 2 intervention cohorts: (1) experimental group (rTMS+MI group) was applied at 1 Hz rTMS over the primary motor cortex of the contralesional hemisphere combined with audio-based MI; (2) control group (rTMS group) received the same therapeutic parameters of rTMS combined with audiotape-led relaxation. LF-rTMS protocol was conducted in 10 sessions over 2 weeks for 30 min. Functional measurements include Wolf Motor Function Test (WMFT), the Fugl-Meyer Assessment Upper Extremity (UE-FMA) subscore, the Box and Block Test (BBT), and the Modified Barthel index (MBI) were conducted at baseline, the second week (week 2) and the fourth week (week 4).Results: All assessments of upper limb function improved in both groups at weeks 2 and 4. In particular, significant differences were observed between two groups at end-intervention and after intervention (p < 0.05). In these findings, we saw greater changes of WMFT (p < 0.01), UE-FMA (p < 0.01), BBT (p < 0.01), and MBI (p < 0.001) scores in the experimental group.Conclusions: LF-rTMS combined with MI had a positive effect on motor function of upper limb and can be used for the rehabilitation of upper extremity motor recovery in stroke patients.

Retinoblastoma (Rb) is the most common intra-ocular malignancy in children. The association of rs2279744, and rs937283 in MDM2 gene, and p21 rs1801270 polymorphism and RB development have been demonstrated. To provide a comprehensive assessment of and to clarify associations between the 3 SNPs (MDM2 rs2279744, MDM2 rs937283, and p21 rs1801270) and the risk of RB, we performed a meta-analysis of all the eligible case-control studies. We searched English databases include PubMed, Embase, Google Scholar, and Cochrane Library, using an upper date limit of January 1, 2018. The association between MDM2 rs2279744, MDM2 rs937283, and p21 rs1801270 polymorphisms and the risk of RB were estimated by calculating a pooled OR and 95% CI under a homozygote comparison, heterozygote comparison, dominant model, and recessive model. The statistical power analysis was performed using G∗Power. Our meta-analysis showed a significant association between RB susceptibility and MDM2 rs2279744 recessive model (OR = 1.427, 95%CI: 1.107-1.840, P = .006, I2 = 0%). Moreover, a significant link was observed between RB risk and MDM2 rs937283 homozygote comparison (OR = 0.471, 95%CI: 0.259-0.858, P = .014, I2 = 0%) and recessive model (OR = 0.587, 95%CI: 0.410-0.840, P = .004, I2 = 0%). However, no significant relationship between the p21 rs1801270 polymorphism and RB susceptibility was detected in any of the 4 models (P > .05). In conclusion, we found that significant association between the MDM2 rs2279744 polymorphism and increased RB risk, while MDM2 rs937283 polymorphism was associated with significantly decreased RB risk. However, as to the P21 rs1801270 polymorphism, a statistically significant association was not identified for RB.

In article number 1903252, Congxin Xia, Yufang Liu, Jingbo Li, Zhongming Wei, and co‐workers describe a reversible diode based on 2D InSe/GeSe van der Waals heterostructure. In the image, yellow lines decorated on the substrate, which are apparently severed but actually connected, implies the near‐broken band alignment of this diode. The diode can be effectively reversed by gate‐bias (control box) through the modulation of band alignment from staggered type to broken type. As shown in the cover image, the unique characteristics of this device are expected to be the core of a motor controller with the speed and direction modulation. [Image: see text]

Corticosteroid therapy is now recommended as a treatment in patients with severe COVID-19. But one key question is how to objectively identify severely ill patients who may benefit from such therapy. Here, we assigned 12,862 COVID-19 cases from 21 hospitals in Hubei Province equally to a training and a validation cohort. We found that a neutrophil-to-lymphocyte ratio (NLR) > 6.11 at admission discriminated a higher risk for mortality. Importantly, however, corticosteroid treatment in such individuals was associated with a lower risk of 60-day all-cause mortality. Conversely, in individuals with an NLR ≤ 6.11 or with type 2 diabetes, corticosteroid treatment was not associated with reduced mortality, but rather increased risks of hyperglycemia and infections. These results show that in the studied cohort corticosteroid treatment is associated with beneficial outcomes in a subset of COVID-19 patients who are non-diabetic and with severe symptoms as defined by NLR., Graphical Abstract, While corticosteroid therapy is effective in the treatment of patients with severe COVID-19, a quantitative clinical parameter to identify such severity and which patients would respond well to corticosteroids has not been developed. Here, Cai et al. find that a simple blood test that measures the neutrophil-to-leukocyte ratio at admission discriminates high versus low mortality risk and a better response to corticosteroid therapy.