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Internal electric field modulation by copper vacancy concentration of cuprous sulfide nanosheets for enhanced selective CO_(2) photoreduction

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Journal of Energy Chemistry 2024年第4期91卷 324-330页

作者： Xian Shi Weidong Dai xiaoqian Li Yang Bai Qin Ren yao Lei Xing'an Dong School of Chemistry and Environmental Engineering Sichuan University of Science&EngineeringZigong 643000SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation School of Oil&Natural Gas EngineeringSouthwest Petroleum UniversityChengdu 610500SichuanChina Chongqing Key Laboratory of Photo-Electric Functional Materials College of Physics and Electronic EngineeringChongqing Normal UniversityChongqing 401331SichuanChina Research Center for Environmental and Energy Catalysis Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu 611731SichuanChina

Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a challenge.Herein,cuprous sulfide nanosheets with different Cu vacancy concentration were employed to study IEF modulation and corresponding direct charge transfer.Among the samples,Cu_(1.8)S nanosheets possessed intensified IEF intensity compared with those of Cu_(2)S and Cu_(1.95)S nanosheets,suggesting that an enhanced IEF intensity could be achieved by introducing more Cu vacancies.This intensified IEF of Cu_(1.8)S nanosheets induced numerous photogenerated electrons to migrate to its surface,and the dissociative electrons were then captured by Cu vacancies,resulting in efficient charge separation spatially.In addition,the Cu vacancies on Cu_(1.8)S nanosheets accumulated electrons as active sites to lower the energy barrier of rate-determining step of CO_(2)photoreduction,leading to the selective conversion of CO_(2)to CO.Herein,the manipulation of IEF intensity through Cu vacancy concentration regulation of cuprous sulfide photocatalysts for efficient charge separation has been discussed,providing a scientific strategy to rationally improve photocata lytic performances for solar energy conversion.

关键词： Internal electric field intensity Cuprous sulfide photocatalysts Cu vacancies Charge separation Selective CO_(2) photoreduction

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Punicalagin prevents obesity-related cardiac dysfunction through promoting DNA demethylation in mice

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Food Science and Human Wellness 2024年第3期13卷 1465-1474页

作者： Shengjie Pei Run Liu Qingqing Ma Peng Jiang Xin He Zhongshi Qi Jiacheng Fang Xu Yang Zirui yao xiaoqian Liu Xianfeng Jing Lei Chen Duo Li Institute of Nutrition&Health Qingdao UniversityQingdao 266071China School of Public Health Qingdao UniversityQingdao 266071China Central Laboratory Guizhou Aerospace HospitalZunyi 563000China Health Centers of Licha Town Qingdao 266071China College of Computer Science and Technology Qingdao UniversityQingdao 266071China

The aim of this study was to investigate whether punicalagin(PU)could prevent obesity-related cardiac dysfunction by promoting DNA demethy lation,and to explore its possible mechanism.C57BL/6J mice were fed with standard diet,high-fat diet(HFD),HFD supplemented with resveratrol,low-dose PU(LPU)and high-dose PU(HPU)for 8 weeks.Compared with HFD group,body weight was significantly lower in PU treatment groups,number of cardionwocytes and the protein level of myosin heavy chain 7B were significantly higher in PU treatment groups.Levels of 5-hydroxymethylcytosine and 5-formylcytosine were significantly lower in HFD group than in other groups.Compared with the HFD group,the protein level of ten-eleven translocation enzyme(TET)2 was significantly higher in PU treatment groups,p-AMP-activated protein kinase(AMPK)was significantly higher in LPU group.Levels of total antioxidant capacity and the protein levels of complexesⅡ/Ⅲ/Ⅴ,oxoglutarate dehydrogenase,succinate dehydrogenase B and fumarate hdrolase were significantly lower in HFD group than PU treatment group.The ratio of(succinic acid+fumaric acid)/a-ketoglutarate was significantly higher in HFD group than other groups.In conclusion,PU up-regulated TETs enzyme activities and TET2 protein stability through alleviating mitochondrial dysfunction and activating AMPK,so as to promote DNA demethylation,thus preventing obesity-related cardiac dysfunction.

关键词： DNA demethylation Mitochondrial function Obesity-related cardiac dysfunction Punicalagin Ten-eleven translocation family enzymes

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A novel topology with controllable wideband baseband impedance for power amplifiers

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 308-315页

作者： yao yao Zhijiang DAI Mingyu LI School of Intelligent Technology and Engineering Chongqing University of Science and TechnologyChongqing400065China School of Microelectronics and Communication Engineering Chongqing UniversityChongqing400065China

This paper presents a novel topology to control the baseband impedance of a power amplifier(PA)to avoid performance deterioration in concurrent dual-band mode.This topology can avoid pure resonance of capacitors and inductors LC,which leads to a high impedance at some frequency points.Consequently,it can be applied to transmitters that are excited by broadband signals.In particular,by adjusting the circuit parameters and increasing stages,the impedance of the key frequency bands can be flexibly controlled.A PA is designed to support this design idea.Its saturated output power is around 46.7 dBm,and the drain efficiency is>68.2%(1.8-2.3 GHz).Under concurrent two-tone excitation,the drain efficiency reaches around 40%even under 5.5 dB back-off power with the tone spacing from 10 MHz to 500 MHz.These results demonstrate that the proposed topology is capable of controlling wideband baseband impedance.

关键词： Baseband impedance Concurrent dual-band Power amplifier

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新质生产力的时代内涵、战略价值与实现路径

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重庆大学学报(社会科学版) 2024年第1期30卷 112-128页

作者：姚树洁张小倩重庆大学经济与工商管理学院辽宁大学李安民经济研究院

加快形成新质生产力，是新时代背景下中国经济社会发展从传统要素驱动向创新驱动转型，提升生产效率和质量，促进经济增长持续健康发展，把握新工业革命浪潮，构筑新竞争优势、赢得发展主动权的题中应有之义。本文明确新质生产力的概念... 详细信息

加快形成新质生产力，是新时代背景下中国经济社会发展从传统要素驱动向创新驱动转型，提升生产效率和质量，促进经济增长持续健康发展，把握新工业革命浪潮，构筑新竞争优势、赢得发展主动权的题中应有之义。本文明确新质生产力的概念及内涵，揭示其理论逻辑、战略价值和实现路径。结合新质生产力的提出背景与相关论述，文章认为新质生产力必须具有“科技创新驱动”“产业高效低耗和环境可持续”“高品质生活和社会服务均等化”“数字赋能”和“国家治理能力现代化”等特征。解构改革开放以来中国新质生产力发展所积累的物质技术基础和政策环境保障，对比分析中国与全球主要国家数字经济发展水平与高科技产品的出口现状，以客观把握中国新质生产力的发展优势与不足。分析在内部面临产业升级滞后与创新能力不足、资源与环境约束、区域城乡发展不平衡、人口结构老龄化与劳动力成本上升、政府治理效率还需提升等“中等收入陷阱”的挑战，外部遭受贸易争端、技术封锁、人权和意识形态威胁、国家领土争端等“修昔底德陷阱”的压力下，新质生产力破解经济高质量发展难题的战略指导意义。进一步地，指出新质生产力的提升是实现国家安全的重要基础，为国家提供了强大的安全保障，有助于构建坚固的国家安全体系。在此基础上，国家安全稳定也是发展新质生产力的必要条件，两者相得益彰。最后，提出为发展新质生产力，尤其注重新质生产力的均衡布局；从内部加强自我建设，释放新质生产力的发展潜能，破除“中等收入陷阱”魔咒；打造安全稳定的外部环境，给新质生产力的发展提供基础保障，破除“修昔底德陷阱”魔咒，支撑构建强劲有力的“双循环”新发展格局。

关键词：新质生产力经济高质量发展区域均衡发展国家安全

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New progress of small-molecule drugs in the treatment of inflammatory bowel disease

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Chinese Medical Journal 2024年第5期137卷 556-558页

作者： Dongying yao Zhihua Ran Department of Gastroenterology Zhou Pu Hospital affiliated to Shanghai University of Health&Medical SciencesShanghai 201318China

With the advent of small-molecule drugs,treatment of inflammatory bowel disease(IBD)has reached a new stage.In contrast to biologics,small-molecule drugs can be made into oral dosage forms with a short half-life and are suitable for administration 1–2 times a day.Small-molecule drugs work by inhibiting the transmission of key intracellular signaling pathways in the pathogenesis of ulcerative colitis(UC)and Crohn’s disease(CD)[Figure 1].They do not induce anti-drug antibodies in patients or lead to loss of response after treatment.

关键词： drugs treatment inflammatory

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Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： Yang Yang Guanxin yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers respectively.The results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making

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Analysis of influencing factors of anxiety and depression in patients with periodontitis

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World Journal of Psychiatry 2024年第1期14卷 141-147页

作者： yao Kong Department of Stomatology Xinxiang Central HospitalXinxiang 453000Henan ProvinceChina

BACKGROUND Periodontitis is a chronic oral disease caused by pathogenic microorganisms that corrode tooth tissue,form periodontal pockets,absorb alveolar bone,and finally lead to tooth loss.During treatment,patients are prone to anxiety,tension,and other negative emotions,which affect their ability to face the disease and may also lead to aggravation of the original condition and affect oral health.Therefore,it is important to improve the negative psychology of patients with periodontitis to clarify the factors that may lead to negative psychological emotions.AIM To investigate the risk factors that may lead to anxiety and depression in patients with periodontitis.METHODS One hundred patients with periodontitis were selected between March 2022 and March 2023 at our hospital.All patients were assessed with the Zung Self-rating Depression Scale(SDS)(≥53 points indicate a depressive state)and Zung Selfrating Anxiety Scale(SAS)(≥50 points indicates an anxious state).In this study,patients who experienced anxiety or depression were included in the occurrence group and those without anxiety or depression were included in the nonoccurrence group.The baseline data of the two groups were compared to explore the risk factors for anxiety and depression in patients with periodontitis.RESULTS A total of 100 patients with periodontitis were included in this study.According to the SDS,38 patients(38.00%)developed depression,with an average SDS score of(68.52±5.85)points.According to the SAS,40 patients(40.00%)developed anxiety,and the average SAS score was(72.15±4.15)points.In this study,56 patients with anxiety or depression were included.Compared with the nonoccurrence group,the occurrence group had higher ages(≥60 years),lower level of hope(low level),educational level(high school or below),disease perception(poor),and sleep disorder(yes).The negative coping dimension scores of the simplified coping style questionnaire(SCSQ)and Dental Fear Scale(DFS)in the occurrence group were higher,whereas the score of the positive coping

关键词： Periodontitis Anxiety Depression Mental state Influencing factor

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Limits of Uneven Battery Power in Modular Multilevel Converter-based Battery Energy Storage Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 686-695页

作者： yao Pan Xiaofeng Sun Wei Zhao Xin Li yao Cai Institute of Electrical Engineering Yanshan UniversityQinhuangdao 066004China

For modular multilevel converter-based battery energy storage systems (MMC-BESS), uneven power among batteries of SMs will be deduced by battery aging, battery fault, etc., which will degrade performance and even lead to system failure. For maintaining the balance of capacitor voltage, this paper analyzes the limits of the uneven power of batteries, which are presented as the current limits in this paper. According to analysis, an analytical method is proposed that only the dc and fundamental frequency components of the arm current are used to calculate current limits. With the current limits it is able to evaluate the reasonability of power distribution among batteries. Meanwhile, increase of fundamental frequency component will enhance the current limits, and the dc component determines the size relationship between the absolute values of the upper and lower current limits. Finally, simulation model and experiment prototype are built for verifying the theoretical analysis and current limits calculation method, and satisfactory results are provided.

关键词： Arm current balance of capacitor voltage current limits MMC-BESS uneven power

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Reinforcement learning based adaptive control for uncertain mechanical systems with asymptotic tracking

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Defence Technology（防务技术） 2024年第4期34卷 19-28页

作者： Xiang-long Liang Zhi-kai yao yao-wen Ge Jian-yong yao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China College of Automation&College of Artificial Intelligence Nanjing University of Post and TelecommunicationNanjing210023China

This paper mainly focuses on the development of a learning-based controller for a class of uncertain mechanical systems modeled by the Euler-Lagrange formulation.The considered system can depict the behavior of a large class of engineering systems,such as vehicular systems,robot manipulators and satellites.All these systems are often characterized by highly nonlinear characteristics,heavy modeling uncertainties and unknown perturbations,therefore,accurate-model-based nonlinear control approaches become unavailable.Motivated by the challenge,a reinforcement learning(RL)adaptive control methodology based on the actor-critic framework is investigated to compensate the uncertain mechanical dynamics.The approximation inaccuracies caused by RL and the exogenous unknown disturbances are circumvented via a continuous robust integral of the sign of the error(RISE)control approach.Different from a classical RISE control law,a tanh(·)function is utilized instead of a sign(·)function to acquire a more smooth control signal.The developed controller requires very little prior knowledge of the dynamic model,is robust to unknown dynamics and exogenous disturbances,and can achieve asymptotic output tracking.Eventually,co-simulations through ADAMS and MATLAB/Simulink on a three degrees-of-freedom(3-DOF)manipulator and experiments on a real-time electromechanical servo system are performed to verify the performance of the proposed approach.

关键词： Adaptive control Reinforcement learning Uncertain mechanical systems Asymptotic tracking

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Lesson Learned from COVID-19 Retrospective Study: An Entropy-Based Clinical-Interpretable Scorecard for Mortality Risk Control at ICU Admission

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Tsinghua Science and Technology 2024年第1期29卷 34-45页

作者： Chong yao Chonghui Huangqi Anpeng Huang Laboratory of Network Information Security Beihang UniversityBeijing 100191China Andrew and Erna Viterbi School of Engineering University of Southern CaliforniaLos AnglesCA 90089USA Beijing Goodwill Information and Technology Co. Ltd.and Mobile Health LaboratoryPeking UniversityBeijing 100871China

With severe acute respiratory syndrome coronavirus 2 spreading globally and causing 2019 coronavirus disease(COVID-19),a challenge that we unprepared for was about how to optimally plan and distribute limited top-medical resources for patients in need of urgent care.To address this challenge,physicians desperately needed a scientific tool to methodically differentiate between cases with varying severity.In this study,the unique data of COVID-19 intensive care unit(ICU)patients provided by the national medical team in Wuhan were classified into discrete and continuous variable types.All continuous data were discretized using an entropy-based method and transformed into serial information margins,in which each information margin is related to a specific symptom or clinical meaning.Finally,all these native and processed discrete data were used to configure a readable scorecard through logistic regression,which is the desired scientific tool aforementioned.A total of 322 ICU patients(age:[median:64,interquartile range:54-75],males:178[55.28%],and death:72[22.36%])were included in the study.Probabilities of mortality in COVID-19 patients can be evaluated using a scorecard model(calibration slope:1.343,Brier:0.048,Dxy=0.972,and population stability index=0.071),with desired model performances(accuracy=0.948,area under curve=0.99,sensitivity=1,and specificity=0.939).This new model can interpret clinical meanings from complex data,and compare it with existing machine learning methods through a black-box mechanism.This new data-information model answers a critical question of how a computing algorithm produces clinically meaningful results that will help physicians logically allocate medical resources for COVID-19 patients.Notably,this tool has limitations,giving that this research is a retrospective study.Hopefully,this tool will be tested further and optimized for adaptation to similar clinical cases in the future.

关键词： COVID-19 scorecard clinical-interpretable machine learning ICU admission control

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