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Preoperative controlling nutritional status as an optimal prognostic nutritional index to predict the outcome for colorectal cancer 被引量:1
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作者 Li-Xiang Liu Hao Wang +6 位作者 Bo Gao Ting-Ting Xu Qing-Gang Yuan Shi-Zhen Zhou Chao Ding Ji Miao Wen-Xian Guan 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期343-353,共11页
BACKGROUND The controlling nutritional status(CONUT)score effectively reflects a patient’s nutritional status,which is closely related to cancer prognosis.This study invest-igated the relationship between the CONUT s... BACKGROUND The controlling nutritional status(CONUT)score effectively reflects a patient’s nutritional status,which is closely related to cancer prognosis.This study invest-igated the relationship between the CONUT score and prognosis after radical surgery for colorectal cancer,and compared the predictive ability of the CONUT score with other indexes.AIM To analyze the predictive performance of the CONUT score for the survival rate of colorectal cancer patients who underwent potentially curative resection.METHODS This retrospective analysis included 217 patients with newly diagnosed colorectal.The CONUT score was calculated based on the serum albumin level,total lymphocyte count,and total cholesterol level.The cutoff value of the CONUT score for predicting prognosis was 4 according to the Youden Index by the receiver operating characteristic curve.The associations between the CONUT score and the prognosis were performed using Kaplan-Meier curves and Cox regression analysis.RESULTS Using the cutoff value of the CONUT score,patients were stratified into CONUT low(n=189)and CONUT high groups(n=28).The CONUT high group had worse overall survival(OS)(P=0.013)and relapse-free survival(RFS)(P=0.015).The predictive performance of CONUT was superior to the modified Glasgow prognostic score,the prognostic nutritional index,and the neutrophil-to-lymphocyte ratio.Meanwhile,the predictive performances of CONUT+tumor node metastasis(TNM)stage for 3-year OS[area under the receiver operating characteristics curve(AUC)=0.803]and 3-year RFS(AUC=0.752)were no less than skeletal muscle mass index(SMI)+TNM stage.The CONUT score was negatively correlated with SMI(P<0.01).CONCLUSION As a nutritional indicator,the CONUT score could predict long-term outcomes after radical surgery for colorectal cancer,and its predictive ability was superior to other indexes.The correlation between the CONUT score and skeletal muscle may be one of the factors that play a predictive role. 展开更多
关键词 controlling nutritional status Colorectal cancer Prognostic marker SARCOPENIA Skeletal muscle
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Controlling the dynamic behavior of decentralized cluster through centralized approaches
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作者 袁大明 王培龙 +6 位作者 王鹏 马星宇 汪楚云 王璟 陈怀城 王高 叶方富 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期46-54,共9页
How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation... How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation of group patterns. Centralized systems excel in precise control over individual behavior within a group, ensuring high accuracy and controllability in task execution. Nevertheless, their sensitivity to group size may limit their adaptability to diverse tasks. In contrast, decentralized systems empower individuals with autonomous decision-making, enhancing adaptability and system robustness. Yet, this flexibility comes at the cost of reduced accuracy and efficiency in task execution. In this work, we present a unique method for regulating the centralized dynamic behavior of self-organizing clusters based on environmental interactions. Within this environment-coupled robot system, each robot possesses similar dynamic characteristics, and their internal programs are entirely identical. However, their behaviors can be guided by the centralized control of the environment, facilitating the accomplishment of diverse cluster tasks. This approach aims to balance the accuracy and flexibility of centralized control with the robustness and task adaptability of decentralized control. The proactive regulation of dynamic behavioral characteristics in active matter groups, demonstrated in this work through environmental interactions, holds the potential to introduce a novel technological approach and provide experimental references for studying the dynamic behavior control of large-scale artificial active matter systems. 展开更多
关键词 self-organizing system centralized control dynamics regulation
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Gypsum-based Silica Gel Humidity-controlling Composite Materials:Preparation,Characterization,and Performance
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作者 李曦 冉茂宇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期337-344,共8页
Gypsum was used as substrate,and silica gel was mixed into substrate at a certain mass ratio to prepare humidity-controlling composites;moreover,the moisture absorption and desorption properties of gypsum-based compos... Gypsum was used as substrate,and silica gel was mixed into substrate at a certain mass ratio to prepare humidity-controlling composites;moreover,the moisture absorption and desorption properties of gypsum-based composites were compared with adding different silica gel particle size and proportion.The morphological characteristics,the isothermal equilibrium moisture content curve,moisture absorption and desorption rate,moisture absorption and desorption stability,and humidity-conditioning performance were tested and analyzed.The experimental results show that,compared with pure-gypsum,the surface structure of the gypsum-based composites is relatively loose,the quantity,density and aperture of the pores in the structure increase.The absorption and desorption capacity increase along with the increase of silica gel particle size and silica gel proportion.When 3 mm silica gel particle size is added with a mass ratio of 40%,the maximum equilibrium moisture content of humidity-controlling composites is 0.161 g/g at 98% relative humidity(RH),3.22 times that of pure-gypsum.The moisture absorption and desorption rates are increased,the equilibrium moisture absorption and desorption rates are 2.68 times and 1.61 times that of pure-gypsum at 58.5% RH,respectively.The gypsum-based composites have a good stability,which has better timely response to dynamic humidity changes and can effectively regulate indoor humidity under natural conditions. 展开更多
关键词 humidity controlling composite materials GYPSUM silica gel
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Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin
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作者 Xu Zeng Tao Yang +5 位作者 Jian-Wei Feng Cong-Sheng Bian Ming Guan Wei Liu Bing-Cheng Guo Jin Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期791-805,共15页
Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fra... Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated. 展开更多
关键词 FRACTURES Development characteristics controlling factors Shale oil Sweet spot
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Controlling Reactivity of Palladium Amides for Selective Carbonylation towards Urea and Oxamide Derivatives
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作者 WANG Jin-hui CAO Yan-wei HE Lin 《分子催化(中英文)》 CAS CSCD 北大核心 2024年第4期297-308,共12页
Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.... Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.Herein,our study introduces a strategy employing palladium amides,harnessing their unique reactivity control,to direct the selective carbonylation of amines for the targeted synthesis of urea and oxamide derivatives.The palladium amide structure was elucidated using single-crystal X-ray diffraction.Controlled experiments and cyclic voltammetry studies further elucidate that the oxidation of palladium amide or its insertion into a carbonyl group diverges into distinct pathways.By employing sodium percarbonate as an eco-friendly oxidant and base,we have successfully constructed a switchable carbonylation system co-catalyzed by palladium and iodide under room temperature.The utilizing strategy in this study not only facilitates effective control over reaction selectivity but also mitigates the risk of explosions,a critical safety concern in traditional carbonylation methods. 展开更多
关键词 selectivity control palladium catalysis oxidative carbonylation AMINOCARBONYLATION green reagents
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Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China
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作者 Gang Li Xian-Ming Xiao +3 位作者 Bo-Wei Cheng Chen-Gang Lu Yue Feng Dong-Sheng Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1488-1507,共20页
The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not w... The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not well understood.In the present study,two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area,representing the deep-water shelf facies and shallowwater platform facies,respectively,were investigated on the differences of pore types,pore structure and methane adsorption capacity between them,and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were discussed.The results show that the organic matter(OM)pores in the YD4 shale samples are dominant,while the inorganic mineral(IM)pores in the YD5 shale samples are primary,with underdeveloped OM pores.The pore specific surface area(SSA)and pore volume(PV)of the YD4 shale samples are mainly from micropores and mesopores,respectively,while those of the YD5 shale samples are mainly from micropores and macropores,respectively.The methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples,with a maximum absolute adsorption capacity of 3.13 cm^(3)/g and 1.31 cm^(3)/g in average,respectively.Compared with the shallow-water platform shale,the deep-water shelf shale has a higher TOC content,a better kerogen type and more developed OM pores,which is the main mechanism for its higher adsorption capacity.The GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 34 m^(3)/t within a depth range of 1000—4000 m,with shale gas exploration and development potential,while the shallow-water platform shale has normally a GIP content of<1 m^(3)/t,with little shale gas potential.Considering the geological and geochemical conditions of shale gas formation and preservation,the deep-water shelf facies is the most favorable target for the Lower Cambrian shale gas exploration and development in the western Hubei area,South China. 展开更多
关键词 Lower Cambrian shale Deep-water shelf facies Shallow-waterplat form facies Pore structure Methane adsorption Gas-in-place content controlling factor
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Spatial-temporal heterogeneity and controlling factors of evapotranspiration in Nujiang River Basin based on Variable Infiltration Capacity(VIC)model
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作者 ZHANG Xianhe LIU Shiyin +1 位作者 ZHU Yu XIE Fuming 《Journal of Mountain Science》 SCIE CSCD 2024年第11期3598-3614,共17页
Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by la... Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by large elevation gradient and different vegetation zones with complex processes of water and energy exchange.The quality of ET from optical remote sensing is constrained by cloud cover which is common in the NRB in the monsoon seasons.To understand factors controlling the spatial-temporal heterogeneity of ET in NRB,we employed the Variable Infiltration Capacity(VIC)hydrological model by parameter optimization with support of quality controlled remote sensing ET product and observed river runoff series in the river.The modeled ET has increased during 1984-2018,which might be one of the reasons for the runoff decrease but precipitation increase in the same period.ET increase and runoff decrease tended to be quicker within altitudinal band of 2000-4000 m than in other areas in NRB.We observed that ET variation in different climatic zones were controlled by different factors.ET is generally positively correlated with precipitation,temperature,and shortwave radiation but negatively with relative humidity.In the Tundra Climate(Et)zone in the upper reach of NRB,ET is controlled by precipitation,while it is controlled by shortwave radiation in the snow climate with dry winter(Dw)zone.ET increase is influenced by the increase of temperature,wind speed,and shortwave radiation in the middle and downstream of NRB with warm temperate climate,fully humid(Cf)and warm temperate climate with dry winter(Cw). 展开更多
关键词 EVAPOTRANSPIRATION Variable infiltration capacity(VIC)model Spatial temporal heterogeneity Climate change controlling factors Nujiang River Basin
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Enrichment model and major controlling factors of below-source tight oil in Lower Cretaceous Fuyu reservoirs in northern Songliao Basin,NE China
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作者 WANG Xiaojun BAI Xuefeng +9 位作者 LI Junhui JIN Zhijun WANG Guiwen CHEN Fangju ZHENG Qiang HOU Yanping YANG Qingjie LI Jie LI Junwen CAI Yu 《Petroleum Exploration and Development》 SCIE 2024年第2期279-291,共13页
Based on the geochemical,seismic,logging and drilling data,the Fuyu reservoirs of the Lower Cretaceous Quantou Formation in northern Songliao Basin are systematically studied in terms of the geological characteristics... Based on the geochemical,seismic,logging and drilling data,the Fuyu reservoirs of the Lower Cretaceous Quantou Formation in northern Songliao Basin are systematically studied in terms of the geological characteristics,the tight oil enrichment model and its major controlling factors.First,the Quantou Formation is overlaid by high-quality source rocks of the Upper Cretaceous Qingshankou Formation,with the development of nose structure around sag and the broad and continuous distribution of sand bodies.The reservoirs are tight on the whole.Second,the configuration of multiple elements,such as high-quality source rocks,reservoir rocks,fault,overpressure and structure,controls the tight oil enrichment in the Fuyu reservoirs.The source-reservoir combination controls the tight oil distribution pattern.The pressure difference between source and reservoir drives the charging of tight oil.The fault-sandbody transport system determines the migration and accumulation of oil and gas.The positive structure is the favorable place for tight oil enrichment,and the fault-horst zone is the key part of syncline area for tight oil exploration.Third,based on the source-reservoir relationship,transport mode,accumulation dynamics and other elements,three tight oil enrichment models are recognized in the Fuyu reservoirs:(1)vertical or lateral migration of hydrocarbon from source rocks to adjacent reservoir rocks,that is,driven by overpressure,hydrocarbon generated is migrated vertically or laterally to and accumulates in the adjacent reservoir rocks;(2)transport of hydrocarbon through faults between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downward through faults to the sandbodies that are separated from the source rocks;and(3)migration of hydrocarbon through faults and sandbodies between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downwards through faults to the reservoir rocks that are separated from the source rocks,and then migrates laterally through sandbodies.Fourth,the differences in oil source conditions,charging drive,fault distribution,sandbody and reservoir physical properties cause the differential enrichment of tight oil in the Fuyu reservoirs.Comprehensive analysis suggests that the Fuyu reservoir in the Qijia-Gulong Sag has good conditions for tight oil enrichment and has been less explored,and it is an important new zone for tight oil exploration in the future. 展开更多
关键词 northern Songliao Basin Cretaceous Quantou Formation Qingshankou Formation upper generation and lower storage Fuyu reservoir tight oil main control factor enrichment model
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Differences in hydrocarbon accumulation and controlling factors of slope belt in graben basin: A case study of Pinghu Slope Belt in the Xihu sag of the east China Sea Shelf basin(ECSSB)
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作者 Bo Yan Hong-Qi Yuan +5 位作者 Ning Li Wei Zou Peng Sun Meng Li Yue-Yun Zhao Qian Zhao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期2901-2926,共26页
The Pinghu slope belt in the Xihu sag of the East China Sea Shelf Basin(ECSSB) is a crucial hydrocarbon production area in eastern China. However, due to the complex geological conditions, publications have lacked com... The Pinghu slope belt in the Xihu sag of the East China Sea Shelf Basin(ECSSB) is a crucial hydrocarbon production area in eastern China. However, due to the complex geological conditions, publications have lacked comprehensive research on the spatial-temporal coupling relationships of primary factors that impact hydrocarbon accumulation in the Pinghu slope belt. Furthermore, the hydrocarbon distribution patterns and the controlling factors across different study areas within the same slope belt are not yet fully understood. This study extensively utilized three-dimensional seismic data, well logging data,geochemical analysis, fluorescence analysis, and oil testing and production data to address these issues.Following a “stratification and differentiation” approach, the study identified seven distinct hydrocarbon migration and accumulation units(HMAU) in the Pinghu slope area based on the structural morphology characteristics, hydrocarbon source-reservoir-cap rock patterns, hydrocarbon migration pathways, and hydrocarbon supply range. Detailed analysis was conducted to examine the hydrocarbon distribution patterns and controlling factors within each migration and accumulation unit across different structural units, including high, medium, and low structural components. All data sources support a “southern-northern sub-area division, eastern-western sub-belt division, and variations in hydrocarbon accumulation” pattern in the Pinghu slope belt. The degree of hydrocarbon accumulation is controlled by the factors of structural morphology, hydrocarbon generation potential of source rocks, the spatial position of source slopes, fault sealing capacity, and sand body distribution. Furthermore, different coupling patterns of faults and sand bodies play a pivotal role in governing hydrocarbon enrichment systems across various migration and accumulation units. These observations indicate that three hydrocarbon accumulation patterns have been established within the slope belt, including near-source to far-source gentle slope with multiple hydrocarbon kitchens in the XP1-XP4 zones, near-source to middle-source gentle slope with dual-hydrocarbon kitchens in the XP5 zone, and near-source steep slope with a single hydrocarbon kitchen in the XP6-XP7 zones. These findings contribute to enhancing the theoretical system of hydrocarbon accumulation in the slope belt. 展开更多
关键词 East China Sea Shelf Basin(ECSSB) Pinghu slope belt Variation in hydrocarbon accumulation controlling factors of hydrocarbon accumulation Hydrocarbon accumulation pattern
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Treatment of Coronary Heart Disease from the Perspective of Liver Controlling Dispersion
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作者 Lijun Zhang Jingyun Sun +1 位作者 Tingting He Yalin Qian 《Journal of Clinical and Nursing Research》 2024年第2期158-164,共7页
The liver is in charge of distributing and regulating the movement of qi throughout the whole body,coordinating the transportation and transformation of the internal organs in the middle part of the body,promoting the... The liver is in charge of distributing and regulating the movement of qi throughout the whole body,coordinating the transportation and transformation of the internal organs in the middle part of the body,promoting the biochemical circulation of qi,blood,and body fluids,and regulating emotions.Liver dysfunction can disrupt the transportation and transformation of qi,blood,and body fluids,causing phlegm turbidity,blood stasis,and other unwanted symptoms.Poor regulation of emotion further aggravates the accumulation of pathological substances,resulting in the obstruction of heart vessels,and ultimately coronary heart disease(CHD).Through regulating lipid metabolism,inflammatory reaction,vasoactive substances,platelet function,neuroendocrine,and other factors,liver controlling dispersing qi plays a comprehensive role in the prognosis of atherosclerosis,the primary cause of CHD.Therefore,it is recommended to treat CHD from the perspective of liver-controlling dispersion. 展开更多
关键词 Liver controlling dispersion Coronary atherosclerotic heart disease ATHEROSCLEROSIS Traditional chinese medicine TREATMENT
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Study of Controlling Clutch Engagement for AMT Based on Fuzzy Logic 被引量:16
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作者 汤霞清 侯朝桢 陈云窗 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期45-49,共5页
The control of the clutch engagement for an automatic mechanical transmission in the process of a tracklayer getting to start is studied. The dynamic model of power transmission and automatic clutch system is develope... The control of the clutch engagement for an automatic mechanical transmission in the process of a tracklayer getting to start is studied. The dynamic model of power transmission and automatic clutch system is developed. Using tools of Simulink, the transient characteristics during the vehicle starting, including the jerk and the clutch slip time, are provided here. Based on the analyses of the simulation results and driver’s experiences, a fuzzy controller is designed to control the clutch engagement. Simulation results verify its value. 展开更多
关键词 CLUTCH automatic transmission fuzzy control
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线粒体移植治疗肌少症的潜力
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作者 李伟 尹洪涛 +3 位作者 孙永晨 徐卫娟 孙金玲 金晓东 《中国组织工程研究》 CAS 北大核心 2025年第13期2842-2848,共7页
背景:肌少症是衰老引起的骨骼肌质量和力量下降的一种综合性疾病,是老年人面临的主要健康挑战。越来越多的证据表明,线粒体功能障碍在肌少症的发病机制中起着关键作用。目的:总结线粒体质量控制失调导致肌少症的机制,探讨线粒体移植可... 背景:肌少症是衰老引起的骨骼肌质量和力量下降的一种综合性疾病,是老年人面临的主要健康挑战。越来越多的证据表明,线粒体功能障碍在肌少症的发病机制中起着关键作用。目的:总结线粒体质量控制失调导致肌少症的机制,探讨线粒体移植可能是治疗肌少症的潜在靶点。方法:以“sarcopenia,mitochondrial dysfunction,mitochondrial quality control,mitochondrial transplantation,limitations”和“肌少症,线粒体功能障碍,线粒体质量控制,线粒体移植,局限性”为关键词,检索PubMed和CNKI数据库2009-2023年间相关文献。结果与结论:线粒体功能障碍在肌少症发病机制中发挥关键作用,线粒体移植可能通过改善线粒体生物能量学和调节线粒体相关信号通路成为治疗肌少症的可能策略。虽然部分临床前和临床研究证实线粒体移植治疗各种疾病的潜力,但关于线粒体转移的具体细节方面仍有一些亟待解决的问题。 展开更多
关键词 肌少症 线粒体功能障碍 线粒体质量控制 线粒体移植 局限性
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Formation mechanism and organizational controlling of ultra-fine-grain copper processed by asymmetrical accumulative rolling-bond and annealing 被引量:2
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作者 王军丽 徐瑞东 +2 位作者 王绍华 钱天才 史庆南 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2672-2678,共7页
The initial copper with large grain sizes of 60-100 μm was processed by six passes asymmetrical accumulative rolling-bond (AARB) and annealing, the ultra-fine-grained (UFG) copper with grain size of 200 nm was ob... The initial copper with large grain sizes of 60-100 μm was processed by six passes asymmetrical accumulative rolling-bond (AARB) and annealing, the ultra-fine-grained (UFG) copper with grain size of 200 nm was obtained, and the microstructures and properties were studied. The results show that there are large sub-structures and also texture component C for the UFG copper obtained by six passes AARB, possessing high strength and microhardness in company with poor elongation and conductivity. Thereafter, the UFG copper was annealed at 220 °C for 35 min, in which the sub-structures disappear, the grain boundaries are composed of big angle grain boundaries, and the textures are composed of a variety of texture components and parts of twins. Compared with the UFG copper obtained by six passes AARB, the tensile strength and yield strength for the UFG copper obtained by six passes AARB and annealing at 220 °C for 35 min are decreased slightly, the elongation and conductivity are improved obviously. 展开更多
关键词 ultra-fine-grain copper asymmetrical accumulative rolling-bond ANNEALING formation mechanism organizational controlling elongation conductivity
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光电稳定平台的分数阶降阶自抗扰控制设计
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作者 陈旭 邸宏伟 +1 位作者 林国余 陈佳明 《电光与控制》 北大核心 2025年第1期95-99,共5页
为了提高光电稳定平台的动态性能与抗干扰能力,提出一种分数阶降阶自抗扰控制(FO-RADRC)算法。首先,利用系统输出信号的可测性和可靠性,采用降阶线性扩张状态观测器,提高观测效率和精度;然后,采用分数阶PD(FOPD)作为控制律,从而增强系... 为了提高光电稳定平台的动态性能与抗干扰能力,提出一种分数阶降阶自抗扰控制(FO-RADRC)算法。首先,利用系统输出信号的可测性和可靠性,采用降阶线性扩张状态观测器,提高观测效率和精度;然后,采用分数阶PD(FOPD)作为控制律,从而增强系统的稳定性和控制性能。通过数值仿真实验,与线性自抗扰算法和降阶线性自抗扰算法进行了对比分析。结果表明,所提算法在动态性能指标上均优于对比算法,且在不同频率的等效扰动作用下具有更强的扰动抑制能力。这些结果验证了所提改进算法在提升光电稳定平台控制效果方面的有效性和创新性。 展开更多
关键词 光电稳定平台 分数阶控制 自抗扰控制 降阶线性扩张状态观测器
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基于动力性模糊控制拖拉机遥控换挡设计研究
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作者 刘九庆 王宇航 项前 《农机化研究》 北大核心 2025年第1期218-225,233,共9页
为实现拖拉机遥控换挡,基于动力性模糊控制换挡设计了电控液压换挡系统,并在AMEsim中搭建仿真模型。根据发动机的调速特性,以油门开度、当前的车速和挡位为输入参数建立动力性换挡模型,并根据驾驶员意图和拖拉机状态建立二级模糊控制器... 为实现拖拉机遥控换挡,基于动力性模糊控制换挡设计了电控液压换挡系统,并在AMEsim中搭建仿真模型。根据发动机的调速特性,以油门开度、当前的车速和挡位为输入参数建立动力性换挡模型,并根据驾驶员意图和拖拉机状态建立二级模糊控制器对动力性换挡策略进行修正。同时,设置工况,在MatLab/Simulink中建立拖拉机传动系统模型,利用AMEsim-Simulink进行联合仿真,得到液压缸活塞杆位移曲线,对可行性进行了验证。对比传统换挡与动力性模糊控制换挡,以离合器冲击度、滑摩功等为控制目标进行仿真分析。结果表明:与传统换挡系统相比所设计的系统控制效果较优,满足拖拉机动力性适应性要求。 展开更多
关键词 拖拉机 模糊控制 遥控换挡 仿真分析
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基于自适应滑模控制器的PMSM调速策略研究
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作者 王要强 王秋旭 +2 位作者 聂福全 张晓光 梁军 《郑州大学学报(理学版)》 CAS 北大核心 2025年第1期88-94,共7页
为了提高永磁同步电机的调速性能,滑模控制逐渐取代PI控制被引入控制系统中。但是传统滑模控制中趋近律的趋近速度慢与固有抖振问题制约着滑模控制的发展,为此提出一种改进的滑模趋近律。首先,为了解决传统等速趋近律中趋近速度和抖振... 为了提高永磁同步电机的调速性能,滑模控制逐渐取代PI控制被引入控制系统中。但是传统滑模控制中趋近律的趋近速度慢与固有抖振问题制约着滑模控制的发展,为此提出一种改进的滑模趋近律。首先,为了解决传统等速趋近律中趋近速度和抖振难以平衡的问题,在所提趋近律中引入系统状态变量,并在滑模增益中引入指数项,使其在保证趋近速度的同时抑制滑模抖振。其次,由于开关函数在零点附近具有不连续的特性,会引起滑模抖振,为此采用sat函数代替常规开关函数,能够在保证响应速度的前提下抑制滑模抖振。然后,基于所提趋近律,设计永磁同步电机的滑模速度控制器。最后,仿真和实验结果表明,所提趋近律可以提高永磁同步电机调速系统的控制性能。 展开更多
关键词 永磁同步电机 滑模控制 自适应趋近律 sat函数 系统状态量
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The effects of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents:a meta-analysis
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作者 Xueyun Shao Longfei He Yangyang Liu 《Neural Regeneration Research》 SCIE CAS 2025年第5期1513-1520,共8页
Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase bra... Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase brain-derived neurotrophic factor levels in children and adolescents, the effects of specific types of exercise on brain-derived neurotrophic factor levels are still controversial. To address this issue, we used meta-analytic methods to quantitatively evaluate, analyze, and integrate relevant studies. Our goals were to formulate general conclusions regarding the use of exercise interventions, explore the physiological mechanisms by which exercise improves brain health and cognitive ability in children and adolescents, and provide a reliable foundation for follow-up research. We used the Pub Med, Web of Science, Science Direct, Springer, Wiley Online Library, Weipu, Wanfang, and China National Knowledge Infrastructure databases to search for randomized controlled trials examining the influences of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents. The extracted data were analyzed using Review Manager 5.3. According to the inclusion criteria, we assessed randomized controlled trials in which the samples were mainly children and adolescents, and the outcome indicators were measured before and after the intervention. We excluded animal experiments, studies that lacked a control group, and those that did not report quantitative results. The mean difference(MD;before versus after intervention) was used to evaluate the effect of exercise on brain-derived neurotrophic factor levels in children and adolescents. Overall, 531 participants(60 children and 471 adolescents, 10.9–16.1 years) were included from 13 randomized controlled trials. Heterogeneity was evaluated using the Q statistic and I^(2) test provided by Review Manager software. The meta-analysis showed that there was no heterogeneity among the studies(P = 0.67, I^(2) = 0.00%). The combined effect of the interventions was significant(MD = 2.88, 95% CI: 1.53–4.22, P < 0.0001), indicating that the brain-derived neurotrophic factor levels of the children and adolescents in the exercise group were significantly higher than those in the control group. In conclusion, different types of exercise interventions significantly increased brain-derived neurotrophic factor levels in children and adolescents. However, because of the small sample size of this meta-analysis, more high-quality research is needed to verify our conclusions. This metaanalysis was registered at PROSPERO(registration ID: CRD42023439408). 展开更多
关键词 adolescents brain-derived neurotrophic factor CHILDREN EXERCISE META-ANALYSIS randomized controlled trials
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Advanced Functional Electromagnetic Shielding Materials:A Review Based on Micro‑Nano Structure Interface Control of Biomass Cell Walls
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作者 Yang Shi Mingjun Wu +14 位作者 Shengbo Ge Jianzhang Li Anoud Saud Alshammari Jing Luo Mohammed A.Amin Hua Qiu Jinxuan Jiang Yazeed M.Asiri Runzhou Huang Hua Hou Zeinhom M.El‑Bahy Zhanhu Guo Chong Jia Kaimeng Xu Xiangmeng Chen 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期98-134,共37页
Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and... Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and hierarchical.Due to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding materials.Despite concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding materials.In particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be valuable.The preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and analyzed.The composite methods and fillers of various biomass materials were reviewed.this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field. 展开更多
关键词 Biomass materials Electromagnetic interference shielding Micro-nano structure interface control CONDUCTIVITY
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Effect of Four Pesticides on Controlling Autumn Cowpea Greenhouse Whitefly
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作者 彭昌家 白体坤 +2 位作者 丁攀 冯礼斌 杨宇衡 《Agricultural Science & Technology》 CAS 2016年第9期2119-2123,共5页
In order to mitigate the occurrence and damage of cowpea whitefly, reduce chemical pesticide consumption, residue and environmental pollution, the methods of forecasting, randomized block design andstatistical analysi... In order to mitigate the occurrence and damage of cowpea whitefly, reduce chemical pesticide consumption, residue and environmental pollution, the methods of forecasting, randomized block design andstatistical analysis were used in field efficacy trials, to study the control effect of cowpea anthracnose by usingchemical pesticides dinotefuran, acetamiprid, pymetrozine, and bio-pesticide avermectin. The results showed that after applying 1.85% avermectin EC 375 g, 20% dinotefuran SP 600 g, 5% acetamiprid WP 600 g, and 25% pymetrozine WP 600 g (control pesticide) per hm2 once every 5-8 days, and 3 times continuously underserious autumn occurrence of greenhouse whitefly, the control efficacy was 90.9%, 97.0%, 88.0%, 93.9%respectively on the 7th day after the pesticides application; 97.4%, 92.1%, 84.2%, 89.4% respectively on the 14th day after the pesticides application; and 95.6%, 86.7%, 82.2%, 84.5%, respectively on the 20th day afterthe pesticides application. The control effects among avermectin, acetamiprid and pymetrozine were not significantly different, while the effects of avermectin and pymetrozine were significantly higher than that of acetamiprid on the 7th day. The control effects among avermectin, dinotefuran and pymetrozine were not significantly different, while significantly higher than that of acetamiprid on the 14th day. The control effect of avermectin was significantly higher than that of dinotefuran, acetamiprid and pymetrozine on the 20th day. Meanwhile, the control effect of avermectin was slightly lower, higher and much higher than that of dinotefuran on the 7th, 14th, 20th day respectively after the treatment. These results indicated that the four pesticides,especiaLly biopesticide avermectin, were ideal pesticides, which could not only be used for controlling cowpea whitefly, but also realize modern, green, organic and ecological agricultural production. 展开更多
关键词 COWPEA Greenhouse whitefly Bio-pesticide AVERMECTINS Chemical pesticides DINOTEFURAN ACETAMIPRID PYMETROZINE Control effect
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基于预测误差法的无人机安全控制器设计
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作者 姜燕 王道波 +1 位作者 柏婷婷 张莹 《电光与控制》 北大核心 2025年第1期90-94,共5页
具备安全性的无人机控制器是保障无人机作战完整性的重要因素之一,该控制器能够在安全的界限范围内控制无人机的飞行性能。针对无人机的安全控制器的设计问题,首先,对无人机的闭环控制系统进行分析,并采用非参数预测误差估计的方法对闭... 具备安全性的无人机控制器是保障无人机作战完整性的重要因素之一,该控制器能够在安全的界限范围内控制无人机的飞行性能。针对无人机的安全控制器的设计问题,首先,对无人机的闭环控制系统进行分析,并采用非参数预测误差估计的方法对闭环控制系统中的执行机构模块进行辨识,以证明辨识得到的模型与实际模型无偏;其次,阐明了无人机安全性的含义,并在闭环控制系统的辨识模型的基础上,对无人机的安全控制器进行了设计;最后,以无人机飞行姿态角中的俯仰通道为例,对安全控制器性能进行了仿真验证。实验结果证明了无人机安全控制器的有效性,能够将无人机的飞行性能控制在安全范围内,为飞行安全提供保障。 展开更多
关键词 无人机 闭环控制系统 安全性 控制器 预测误差估计
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