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Early intelligent active assistance in walking for hemiplegic patients under suspension protection: a randomized controlled trial
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作者 Ma Shanxin Zheng Jianling +5 位作者 Cheng Jian Lin Xi Li Qiuyuan Wang Li Zeng Yangkang Song Luping 《中国组织工程研究》 北大核心 2026年第12期3075-3082,共8页
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec... BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function. 展开更多
关键词 hemiplegia stroke suspension protection system personal assistant machine intelligent walking aid early rehabilitation active training walking function NEUROPLASTICITY gait analysis motor function recovery rehabilitation training balance ability
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PATENTS AS PROGRESS China advances IP protection in emerging industries to fuel new growth
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作者 Li Qing 《Beijing Review》 2026年第4期20-21,共2页
On July 11,2025,the global intellectual property(IP)spotlight fell on Geneva,Switzerland.At the 2025 World Intellectual Property Organization(WIPO)Global Awards,Chinese robotics firm Unitree Robotics was named one of ... On July 11,2025,the global intellectual property(IP)spotlight fell on Geneva,Switzerland.At the 2025 World Intellectual Property Organization(WIPO)Global Awards,Chinese robotics firm Unitree Robotics was named one of 10 winners,selected from more than 780 small and medium-sized enterprises(SMEs)and startups across 95 countries and regions.Since the awards were launched in 2022.Chinese companies have won prizes for four consecutive years. 展开更多
关键词 intellectual property geneva China patents PROGRESS emerging industries GROWTH IP protection
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Protective effect of Guanxinning on antipsychotic-induced cardiac impairment in long-term hospitalized psychiatric patients
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作者 Fu-Gang Luo Hao-Yu Xing +4 位作者 Jun-Jie Wang Wen-Ye Wu Kai-Jie Fang Hai-Dong Song Juan Yan 《World Journal of Psychiatry》 2026年第1期221-232,共12页
BACKGROUND Long-term antipsychotic therapy in psychiatric patients carries significant cardiovascular risks,including QT interval prolongation,myocardial injury,and functional impairment.Guanxinning,a traditional Chin... BACKGROUND Long-term antipsychotic therapy in psychiatric patients carries significant cardiovascular risks,including QT interval prolongation,myocardial injury,and functional impairment.Guanxinning,a traditional Chinese medicine formulation,has demonstrated cardioprotective potential in preclinical studies,but clinical evidence in this population remains limited.AIM To evaluate the cardioprotective effects of Guanxinning against antipsychotic-induced cardiac injury in long-term hospitalized psychiatric patients.METHODS A randomized,double-blind,placebo-controlled trial was conducted with 120 psychiatric inpatients receiving chronic antipsychotic therapy.Participants were allocated to:Intervention group:Conventional antipsychotics+Guanxinning tablets(0.38 g×4 tablets,ter in die);Control group:Conventional antipsychotics+identical placebo;Cardiac assessments at baseline and 12 months included:Electrocardiography(corrected QT interval),echocardiography(left ventricular ejection fraction,left ventricular end-diastolic diameter),serum biomarkers(cardiac troponin I,B-type natriuretic peptide,superoxide dismutase,malondialdehyde,high-sensitivity C-reactive protein).RESULTS Compared to controls,the Guanxinning group showed:Electrophysiological improvement:Corrected QT shortening(438±25 milliseconds vs 465±30 milliseconds,P<0.01).Functional enhancement:Left ventricular ejection fraction increase(58.5%±5.2%vs 53.8%±4.8%,P<0.05),left ventricular end-diastolic diameter reduction(49.8±3.5 mm vs 52.6±3.8 mm,P<0.05),Biochemical modulation:Reduced myocardial injury markers(cardiac troponin I:0.009 ng/mL vs 0.014 ng/mL;B-type natriuretic peptide:52 pg/mL vs 78 pg/mL,P<0.001),improved oxidative stress(superoxide dismutase:↑13.3 U/mL;malondialdehyde:↓0.9 nmol/mL,P<0.001),attenuated inflammation(high-sensitivity C-reactive protein:2.0 mg/L vs 3.2 mg/L,P<0.001).CONCLUSION Guanxinning significantly mitigates antipsychotic-induced cardiac injury in psychiatric patients,demonstrating:Normalization of electrophysiological parameters,Preservation of systolic/diastolic function,suppression of oxidative stress and inflammation.These findings support its clinical application as an adjunctive cardioprotective therapy,potentially through inhibition of myocardial apoptosis and antioxidant upregulation. 展开更多
关键词 GUANXINNING Antipsychotic drugs Cardiac function SCHIZOPHRENIA Cardiac protection
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Evolution of the protection system for traditional Chinese medicine varieties and the strategic responses of traditional Chinese medicine enterprises
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作者 Wenli Li Qian Sun +4 位作者 Xiang Li Zhaojun Meng Mengmeng Li Wenxia Ding Pengfei Zhang 《Asian Journal of Traditional Medicines》 2025年第3期130-139,共10页
The protection system for traditional Chinese medicine(TCM)varieties,as an important policy tool to promote the development of TCM,has a long history of over 30 years,from the promulgation of the“Regulations on the P... The protection system for traditional Chinese medicine(TCM)varieties,as an important policy tool to promote the development of TCM,has a long history of over 30 years,from the promulgation of the“Regulations on the Protection of Traditional Chinese Medicine Varieties”in 1992 to the comprehensive revision of the draft for soliciting opinions in 2022.The TCM protection system evolves to meet the needs of innovative development of TCM.This paper reviews the policy developments in TCM varieties protection,collates protection data(1993 to 2024),and analyzes enterprises application strategies amid impending regulatory changes. 展开更多
关键词 protection of traditional Chinese medicine(TCM)varieties policy evolution the exclusive logo of TCM protection patent and TCM protection integration intelligent manufacturing and internationalization
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State of the art and current trends on the metal corrosion and protection strategies in deep sea 被引量:2
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作者 Yangmin Wu Wenjie Zhao Liping Wang 《Journal of Materials Science & Technology》 2025年第12期192-213,共22页
Deep sea,with rich oil,gas,and mineral resources,plays an increasingly crucial role in scientific and industrial realms.However,the highly corrosive feature of deep sea hinders further exploration and development,whic... Deep sea,with rich oil,gas,and mineral resources,plays an increasingly crucial role in scientific and industrial realms.However,the highly corrosive feature of deep sea hinders further exploration and development,which requires metal materials with robust corrosion resistance.This review covers an in-depth and all-around overview of the up-to-date advances in corrosion and protection of metals in deep-sea environment.Firstly,the unique characteristics of deep-sea environment are summarized in detail.Subsequently,the corrosion performances of metals in both in situ and simulated deep-sea environments are illustrated systematically.Furthermore,corrosion prevent strategies of metals,including sacrificial anode protection,organic coatings,as well as coatings achieved by physical vapor deposition(PVD coatings),are highlighted.Finally,we outline current challenges and development trends of corrosion and protection of metals in deep-sea environment in the future.The purpose of this review is not only to summarize the recent progress on metal corrosion and protection in deep sea,but also to aid us in understanding them more comprehensively and deeply in a short time,so as to boost their fast development. 展开更多
关键词 Deep sea Corrosion protection Sacrificial anode protection Organic coatings PVD coatings
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Protecting cultural treasures
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作者 胡金莹 《疯狂英语(新读写)》 2025年第5期44-46,76,共4页
1 In Lichuan,Central China's Hubei Province,a family's dedication to preserving cultural heritage has become a beacon(灯塔)of inspiration.The Sun family,comprised of father Sun Hui and son Sun Ru,has been the ... 1 In Lichuan,Central China's Hubei Province,a family's dedication to preserving cultural heritage has become a beacon(灯塔)of inspiration.The Sun family,comprised of father Sun Hui and son Sun Ru,has been the backbone of the national cultural relics census in Lichuan since the 1970s,embodying the nation's spirit of protecting cultural treasures. 展开更多
关键词 protection Lichuan HubeiProvince protecting cultural treasures cultural relics census INSPIRATION cultural heritage cultural relics
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Topological considerations for reinforced concrete modular protection systems against near-field overpressure generated by close-in detonations
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作者 Sangyoung Han Kukjoo Kim +4 位作者 Hyeon-Jin Kim Jang-Woon Baek Hyun-Do Yun Gyu-Yong Kim Sangwoo Park 《Defence Technology(防务技术)》 2025年第11期112-125,共14页
With the increasing demand for secure infrastructure such as hydrogen refueling stations,chemical plants,and energy storage systems,the need for protective structures capable of withstanding close-in detonations has b... With the increasing demand for secure infrastructure such as hydrogen refueling stations,chemical plants,and energy storage systems,the need for protective structures capable of withstanding close-in detonations has become more critical.Existing design guidelines for protective walls(e.g.,UFC 3-340-02)primarily address mid-and far-field explosions,providing limited insights into near-field effects.Considering the effect of slight slopes(<40°)on reducing maximum reflected overpressure is deemed negligible.This study investigated the effectiveness of a reinforced concrete(RC)modular protection system(MPS)incorpo rating a diagonally tapered wall in attenuating re flected overpressures from closein detonations.Full-scale field experiments using a 51.3 kg TNT charge,representing the explosion energy of a typical hydrogen vessel rupture,demonstrated that a wall with a 7°slope significantly outperformed a vertical wall of equivalent concrete volume in terms of blast resistance.Observed structural responses included cracking,horizontal shear failure,and overturning.Complementary simulations using a validated computational fluid dynamics(CFD)model showed that the tapered wall reduced peak overpressure by 30%-40%compared to an equivalent vertical wall.This result highlights the potential of minor geometric modifications to enhance blast resilience.The tapered design effectively redirects incident blast waves,reducing localized damage while also conserving material,thus preserving modular benefits such as ease of transport and reusability.These findings suggest that diagonally tapered RC-based MPSs can offer a practical and resilient solution for industrial and military applications subject to near-field or sequential blast threats. 展开更多
关键词 Modular protective system protective wall Close-in detonation Near-field overpressure Full-scale explosion test
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How to Protect Our Eyes
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作者 皮红春 张超 《中学生英语》 2025年第27期6-6,共1页
As we all know,eyes are the windows of our souls.They make us see the colorful world and understand others’feelings.However,by①the wide use of digital devices like smartphones and computers,many of us are facing eye... As we all know,eyes are the windows of our souls.They make us see the colorful world and understand others’feelings.However,by①the wide use of digital devices like smartphones and computers,many of us are facing eye problems.So,it's important to protect our eyes。 展开更多
关键词 protect our eyes eye problems eye protection digital devices
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A Collaborative Protection Mechanism for System-on-Chip Functional Safety and Information Security in Autonomous Driving
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作者 Zhongyi Xu Lei Xin +1 位作者 Zhongbai Huang Deguang Wei 《Journal of Electronic Research and Application》 2025年第2期226-232,共7页
This article takes the current autonomous driving technology as the research background and studies the collaborative protection mechanism between its system-on-chip(SoC)functional safety and information security.It i... This article takes the current autonomous driving technology as the research background and studies the collaborative protection mechanism between its system-on-chip(SoC)functional safety and information security.It includes an introduction to the functions and information security of autonomous driving SoCs,as well as the main design strategies for the collaborative prevention and control mechanism of SoC functional safety and information security in autonomous driving.The research shows that in the field of autonomous driving,there is a close connection between the functional safety of SoCs and their information security.In the design of the safety collaborative protection mechanism,the overall collaborative protection architecture,SoC functional safety protection mechanism,information security protection mechanism,the workflow of the collaborative protection mechanism,and its strategies are all key design elements.It is hoped that this analysis can provide some references for the collaborative protection of SoC functional safety and information security in the field of autonomous driving,so as to improve the safety of autonomous driving technology and meet its practical application requirements. 展开更多
关键词 Autonomous driving SoC functional safety Information security Collaborative protection mechanism Collaborative protection architecture
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Novel insights into flow mechanics in ablative thermal protection systems
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作者 Hu REN 《Chinese Journal of Aeronautics》 2025年第10期288-289,共2页
1.Introduction to ablative TPS The Mars 2020 mission underscored the critical role of ablative Thermal Protection Systems(TPS)during atmospheric entry,where spacecraft encounter extreme aerodynamic heating.Established... 1.Introduction to ablative TPS The Mars 2020 mission underscored the critical role of ablative Thermal Protection Systems(TPS)during atmospheric entry,where spacecraft encounter extreme aerodynamic heating.Established in the mid-20th century,blunt body theories led to the creation of ablative heat shields that effectively manage thermal loads through thermo-chemo-mechanical decomposition.This paper revisits the development and application of ablative TPS materials,which are single-mission solutions capable of withstanding entry velocities surpassing 10 km/s. 展开更多
关键词 ablative thermal protection systems tps extreme aerodynamic heatingestablished body theories ablative tps Mars mission manage thermal loads atmospheric entrywhere ablative thermal protection systems
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Digital Inclusion:Research on the Digital Protection of Human Rights
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作者 YU Hao SHI Hanqing 《The Journal of Human Rights》 2025年第3期567-588,共22页
In the digital era,the protection of human rights inevitably integrates digital technology and presents distinctive relevant characteristics.Therefore,the concept of digital inclusion should be introduced.However,the ... In the digital era,the protection of human rights inevitably integrates digital technology and presents distinctive relevant characteristics.Therefore,the concept of digital inclusion should be introduced.However,the protection of human rights in the digital age still faces four significant challenges,namely,limitations in hardware systems with unrealized access rights,lack of digital competency with widening digital divide,low degree of empowerment and inefficiency in digital utilization,as well as frequent digital infringements and compromised digital rights.To address these challenges,it is essential to ensure barrier-free access to information technology to strengthen the foundation of human rights protection,promote the extensive participation of social entities to expand the scope of human rights protection,provide inclusive services for diverse groups to deepen the content of human rights protection,eliminate the digital divide to promote equal realization of human rights protection,and enhance citizens’digital literacy and capabilities to improve the efficacy of digital protection of human rights.Under the framework of digital inclusion,the specific measures to achieve the digital protection of human rights are led by the value orientation and practical needs of the rights to subsistence and development,aiming to advance the universal protection,differential protection,and enhanced protection of human rights through digital inclusion. 展开更多
关键词 digital inclusion human rights protection digital protection
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Assessing the corrosion protection property of coatings loaded with corrosion inhibitors using the real-time atmospheric corrosion monitoring technique 被引量:1
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作者 Xiaoxue Wang Lulu Jin +8 位作者 Jinke Wang Rongqiao Wang Xiuchun Liu Kai Gao Jingli Sun Yong Yuan Lingwei Ma Hongchang Qian Dawei Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期119-126,共8页
The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal materials.However,limited studies have applied ACM to the corrosion protection properties ... The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal materials.However,limited studies have applied ACM to the corrosion protection properties of organic coatings.This study compared a bare epoxy coating with one containing zinc phosphate corrosion inhibitors,both applied on ACM sensors,to observe their corrosion protection properties over time.Coatings with artificial damage via scratches were exposed to immersion and alternating dry and wet environments,which allowed for monitoring galvanic corrosion currents in real-time.Throughout the corrosion tests,the ACM currents of the zinc phosphate/epoxy coating were considerably lower than those of the blank epoxy coating.The trend in ACM current variations closely matched the results obtained from regular electrochemical tests and surface analysis.This alignment highlights the potential of the ACM technique in evaluating the corrosion protection capabilities of organic coatings.Compared with the blank epoxy coating,the zinc phosphate/epoxy coating showed much-decreased ACM current values that confirmed the effective inhibition of zinc phosphate against steel corrosion beneath the damaged coating. 展开更多
关键词 atmospheric corrosion monitoring technology corrosion inhibitor COATING carbon steel corrosion protection
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Blockchain-Enabled Data Secure Sharing with Privacy Protection Based on Proxy Re-Encryption in Web3.0 Applications 被引量:1
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作者 Ma Jiawei Zhou Haojie +2 位作者 Wang Sidie Song Jiyuan Tian Tian 《China Communications》 2025年第5期256-272,共17页
With the rapid development of web3.0 applications,the volume of data sharing is increasing,the inefficiency of big data file sharing and the problem of data privacy leakage are becoming more and more prominent,and the... With the rapid development of web3.0 applications,the volume of data sharing is increasing,the inefficiency of big data file sharing and the problem of data privacy leakage are becoming more and more prominent,and the existing data sharing schemes have been difficult to meet the growing demand for data sharing,this paper aims at exploring a secure,efficient and privacy-protecting data sharing scheme under web3.0 applications.Specifically,this paper adopts interplanetary file system(IPFS)technology to realize the storage of large data files to solve the problem of blockchain storage capacity limitation,and utilizes ciphertext policy attribute-based encryption(CP-ABE)and proxy re-encryption(PRE)technology to realize secure multi-party sharing and finegrained access control of data.This paper provides the detailed algorithm design and implementation of data sharing phases and processes,and analyzes the algorithms from the perspectives of security,privacy protection,and performance. 展开更多
关键词 blockchain data sharing privacy protection proxy re-encryption WEB3.0
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Evaluating Microplastic Concentrations in the Al Hoceima Marine Protected Area:Implications for Identifying Pollution Hotspots and Formulating Conservation Strategies 被引量:1
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作者 Hasna Bouazzati Asma Damghi +2 位作者 Abdelmounim El M’rini Souhail Karim Mohamed Maanan 《Sustainable Marine Structures》 2025年第2期1-21,共21页
Global marine ecosystems are signiicantly endangered by microplastic pollution,leading to comprehensive investigations into its distribution and impacts on the health of ecosystem.This research employs the Alseamar Au... Global marine ecosystems are signiicantly endangered by microplastic pollution,leading to comprehensive investigations into its distribution and impacts on the health of ecosystem.This research employs the Alseamar Autonomous Underwater Vehicle(AUV)known as Glider to investigate microplastic concentrations within the Al Hoceima Marine Protected Area(MPA).Our objective is to identify spatial patterns that reveal pollution hotspots and furnish data for targeted conservation efforts and pollution prevention.We aim to identify regions with elevated microplastic concentrations by meticulously analyzing microplastic level graphs,with a speciic focus on temporal variations.The results reveal notable patterns,such as increased densities aroundishing harbors and near urban centers,potentially linked to anthropogenic activities.Additionally,we observe variations in pollution levels throughout different glider operation cycles,underscoring the importance of understanding the spatio‑temporal dynamics of microplastic distribution.Al Hoceima Marine protected areas exhibiting lower microplastic concentrations illustrate the eficacy of such zones in alleviating pollution impacts,thereby underscoring the signiicance of conservation efforts in safeguarding marine biodiversity and ecosystem resilience.Ultimately,our research enhances our comprehension of the pressures exerted by humans on marine environments and underscores the necessity of proactive conservation measures to shield marine ecosystems from the threats posed by microplastic pollution. 展开更多
关键词 Microplastics Marine protected Area Al Hoceima Gliders Pollution Hotspots Conservation Strategies
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A spotlight on dosage and subject selection for effective neuroprotection: exploring the central role of mitochondria
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作者 John Mitrofanis Jonathan Stone +3 位作者 Michael R.Hamblin Pierre Magistretti Alim-Louis Benabid Glen Jeffery 《Neural Regeneration Research》 SCIE CAS 2025年第4期1081-1082,共2页
Neurons are notoriously vulnerable cell types.Even the slightest change in their internal and/or external environments will cause much distress and dysfunction,leading often to their death.A range of pathological cond... Neurons are notoriously vulnerable cell types.Even the slightest change in their internal and/or external environments will cause much distress and dysfunction,leading often to their death.A range of pathological conditions,including stroke,head trauma,and neurodegenerative disease,can generate stress in neurons,affecting their survival and proper function.In most neural pathologies,mitochondria become dysfunctional and this plays a pivotal role in the process of cell death.The challenge over the last few decades has been to develop effective interventions that improve neuronal homeostasis under pathological conditions.Such interventions,often referred to as disease-modifying or neuroprotective,have,however,proved frustratingly elusive,at both preclinical and,in particular,clinical levels.In this perspective,we highlight two factors that we feel are key to the development of effective neuroprotective treatments.These are:firstly,the choice of dose of intervention and method of application,and secondly,the selection of subjects,whether they be patients or the animal model. 展开更多
关键词 protective DOSAGE DISTRESS
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Simulation Studies of an Integrated Overcurrent Relay Protection Scheme for Distribution Systems 被引量:2
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作者 Z.Q. Bo X.Z. Dong +1 位作者 B.H. Zhang J.H. He 《Journal of Energy and Power Engineering》 2011年第1期55-62,共8页
This paper presents an integrated protection technique for power distribution systems. A novel integrated protection scheme based on overcurrent protection technique for distribution system is described, in which a sp... This paper presents an integrated protection technique for power distribution systems. A novel integrated protection scheme based on overcurrent protection technique for distribution system is described, in which a specially designed protection relay is installed at each substation of a network and responsible for the protection of every line sections connected to the substation busbar The conventional directional overcurrent and the new adaptive accelerated protection algorithms with multiple settings are implemented into the relay to cover all the protected line sections. The paper includes studies of a typical multi section distribution network to demonstrate the principle of the scheme. Studies show that the new scheme not only offer the new protection features for individual power line section, but also provide the characteristics of integrated protection. 展开更多
关键词 Overcurrent protection integrated protection centralized protection network protection digital substation powersystem simulation.
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Effectiveness analysis of corona protection materials for HV rotating machines
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作者 Victor Belko FENG Shengxi +2 位作者 Efrem Feklistov FENG Yu LIU Ji 《电机与控制学报》 北大核心 2025年第4期35-44,共10页
In this paper a fully parametrized finite element simulation model of the stator bar end is created using the COMSOL Multiphysics.The model allows conducting the comparison of different corona protection structures’d... In this paper a fully parametrized finite element simulation model of the stator bar end is created using the COMSOL Multiphysics.The model allows conducting the comparison of different corona protection structures’design,various materials properties,and finally optimizing the corona protection system.Several samples of SiC based nonlinear conductivity materials for corona protection were fabricated in laboratory and then investigated.The conductivity dependencies on electric field(0.05 to 1 kV/mm)and temperature(20 to 155℃)were measured.By comparing the heat-resistant grades of the corona protection material and the insulating material,the maximum working temperature of the corona protection material corresponds to the heat-resistant grade F of the insulating material.As the temperature increases,the nonlinear characteristics of the corona protection material in the experiment decrease dramatically,reducing the heat-resistant grade of the corona protection material.The decrease in the nonlinear characteristics of the corona protection material at the maximum operating temperature causes the maximum electric field strength at the end of the HV rotating machines end corona protection(ECP)exceeding the corona discharge electric field strength,resulting in corona phenomenon. 展开更多
关键词 stator windings partial discharges stress grading corona protection semiconductive materials surface resistance nonlinear properties
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Radioprotection and Medical Monitoring in Health Facilities in Douala, Cameroon
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作者 Owona Manga Léon Jules Mballa Amougou Jean Claude +4 位作者 Mbede Maggy Tchicaya Aimé François Giegui Chimène Pulchérie Manga Romaine Carine Mouelle Sone Albert 《Occupational Diseases and Environmental Medicine》 2025年第1期17-29,共13页
Introduction: The use of radioactive radiations in healthcare facilities must comply with radioprotection safety rules in order to avoid threatening the health of workers and patients. This study aimed to assess the w... Introduction: The use of radioactive radiations in healthcare facilities must comply with radioprotection safety rules in order to avoid threatening the health of workers and patients. This study aimed to assess the working conditions, the protective measures and the medical monitoring of workers directly involved in X-ray work at hospitals in Douala, Cameroon. Materials and Methods: A descriptive cross-sectional study was carried out during the 1st quarter of 2018, across various state and private health facilities of the city of Douala. Sampling was non-random, based on convenience and all the willing participants that fulfilled the inclusion criteria were enrolled. Quantitative analyses were conducted using EPI INFO 7.0 software and the results were presented in both univariate and bivariate forms. Results: The sample consisted of 56 men and 31 women with a mean age of 34.75 ± 8.77 years. X-ray technicians were over-represented (41.38%). Day/night shift work was the main work pattern (68.96%). The distribution of work zones A&B was known by 87.5% of the participants. Hazard warning signs were effective in work zones A and B (75.86%), and the walls of the premises were also reinforced in these work zones (88.51%), but the use of radiation dosimeters was rare (9.20%). Radiation aprons (94.30%) and hand-held dosimeters (63.20%) were the most commonly used personal protective equipment. The majority of the participants did not benefit from medical follow-up by an occupational health specialist (62.1%). Conclusion: The implementation of radiation protection measures remains a significant concern in Douala based health facilities, and requires stricter administrative controls and sanctions to prevent serious health consequences for exposed staff. 展开更多
关键词 Ionizing Radiation HOSPITAL Radiation protection Medical Monitoring Douala
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Assessment of Floristic Diversity at Two Protected Sites on the Outskirts of Sena Oura National Park, Chad
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作者 Robert Tchingonta Maxime Banoin +1 位作者 Koussou Mian-Oudanang Sougnabe Pabame 《Agricultural Sciences》 2025年第1期178-192,共15页
Two protected sites located on the outskirts of the Sena Oura National Park (PNSO) in West Mayo-Kebbi cover an area of 1800 m2 is pattern choose in pastoral enclave in both village. This study was undertaken to highli... Two protected sites located on the outskirts of the Sena Oura National Park (PNSO) in West Mayo-Kebbi cover an area of 1800 m2 is pattern choose in pastoral enclave in both village. This study was undertaken to highlight the floristic diversity of the herbaceous and woody vegetation on these sites in the offing to know the ability of charge into UBT that most support the park peripheral. It took place on two experimental sites on a natural course in two villages: Wazetelan and Massang. The approach used for the study was a survey using the systematic sampling method and a 30 m × 30 m plot. The survey consisted in listing all the taxa in a floristically homogeneous plot, each assigned the Braun-Blanquet dominance abundance coefficient. These surveys revealed a floristic richness of 73 species, 58 genera, including 46 herbaceous and 26 woody species. The Shannon result gives H1' = 0.12 bit for herbaceous species and H2' = 0.44 bit for woody species, meaning that the herbaceous and woody populations of all the surveys have a very low species diversity, as H' < 3 according to the Shannon index assessment threshold. Herbaceous species are divided into 13 families and 33 genera. The most represented families are Fabaceae (27.3%) and Poaceae (21.9%). Most of the other families (1.3%) have only one species, if any. Herbaceous species are divided into 33 genera grouped into 13 families. The most represented families are Fabaces (16 species), 34%, and Poaceae (12 species), 26%. The 26 woody species, most of which come from itinerant surveys, are distributed across 24 genera and 12 families, the most important of which is Fabaceae with 09 species (34.6%). This floristic assessment, in terms of quantity and quality, has enabled us to estimate the carrying capacity of the two pastoral enclaves in Dari and Goumadji cantons, and to guide the government’s actions with regard to rangeland management. 展开更多
关键词 Floristic Diversity protected Sites PERIPHERY Area Producty CHAD
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Biodiversity Characteristics and Protection Countermeasures of Yuncheng Salt Lake
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作者 Yan GUAN Yu ZHANG +2 位作者 Quanxi ZHANG Ruinan GAO Donggang GUO 《Asian Agricultural Research》 2025年第5期1-7,共7页
[Objectives]To explore biodiversity characteristics of Yuncheng Salt Lake and provide protection countermeasures.[Methods]According to the field survey data of 978 plant quadrats and cluster analysis,species diversity... [Objectives]To explore biodiversity characteristics of Yuncheng Salt Lake and provide protection countermeasures.[Methods]According to the field survey data of 978 plant quadrats and cluster analysis,species diversity indicators such as Margalef richness index and Shannon-Wiener index were selected to deeply explore the structure and diversity characteristics of higher plant communities in Yuncheng Salt Lake.[Results]There were 117 species belonging to 97 genera and 35 families of higher plants in Yuncheng Salt Lake,of which Asteraceae and Gramineae were dominant families,and the North Temperate Distribution Genus accounted for 27.35%of the total genera;according to profile coefficient method,the optimal cluster number was 7,which was divided into 7 plant community types,including Artemisia capillaris community and Suaeda glauca(Bunge)community;the Lolium perenne community was the highest(d=2.537),the Artemisia scoparia community was the best(E=0.658),the Suaeda salsa(L.)Pall community was the lowest(H′=1.779),and the spatial distribution of species showed a significant aggregation pattern.[Conclusions]We put forward some countermeasures for biodiversity protection,including constructing dynamic monitoring system,implementing adaptive management strategy and promoting multi-party collaborative governance,so as to provide scientific theoretical basis and practical guidance for ecological restoration and sustainable development of Yuncheng Salt Lake. 展开更多
关键词 Yuncheng SALT LAKE BIODIVERSITY Community classification Diversity index protectION COUNTERMEASURES
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