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Enhancement of motor functional recovery in thoracic spinal cord injury: voluntary wheel running versus forced treadmill exercise
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作者 Do-Hun Lee Dan Cao +4 位作者 Younghye Moon Chen Chen Nai-Kui Liu Xiao-Ming Xu Wei Wu 《Neural Regeneration Research》 SCIE CAS 2025年第3期836-844,共9页
Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery ... Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. Bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury. 展开更多
关键词 behavioral assessment motor function neural plasticity running wheel exercise spinal cord injury treadmill exercise voluntary exercise
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Movement Function Assessment Based on Human Pose Estimation from Multi-View
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作者 Lingling Chen Tong Liu +1 位作者 Zhuo Gong Ding Wang 《Computer Systems Science & Engineering》 2024年第2期321-339,共19页
Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely u... Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely used in motion analysis,medical evaluation,and behavior monitoring.In this paper,the authors propose a method for multi-view human pose estimation.Two image sensors were placed orthogonally with respect to each other to capture the pose of the subject as they moved,and this yielded accurate and comprehensive results of three-dimensional(3D)motion reconstruction that helped capture their multi-directional poses.Following this,we propose a method based on 3D pose estimation to assess the similarity of the features of motion of patients with motor dysfunction by comparing differences between their range of motion and that of normal subjects.We converted these differences into Fugl–Meyer assessment(FMA)scores in order to quantify them.Finally,we implemented the proposed method in the Unity framework,and built a Virtual Reality platform that provides users with human–computer interaction to make the task more enjoyable for them and ensure their active participation in the assessment process.The goal is to provide a suitable means of assessing movement disorders without requiring the immediate supervision of a physician. 展开更多
关键词 Human pose estimation 3D pose reconstruction assessment of movement function plane of features of human motion
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Modified physiological and operative score for the enumeration of mortality and morbidity risk assessment model in general surgery 被引量:10
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作者 Lian-An Ding Li-Qun Sun +2 位作者 Shuang-Xi Chen Lin-Lin Qu Dong-Fang Xie 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第38期5090-5095,共6页
AIM: To establish a scoring system for predicting the incidence of postoperative complications and mortality in general surgery based on the physiological and operative severity score for the enumeration of mortality ... AIM: To establish a scoring system for predicting the incidence of postoperative complications and mortality in general surgery based on the physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM), and to evaluate its efficacy. METHODS: Eighty-four patients with postoperative complications or death and 172 patients without postoperative complications, who underwent surgery in our department during the previous 2 years, were retrospectively analyzed by logistic regression. Fifteen indexes were investigated including age, cardiovascular function, respiratory function, blood test results, endocrine function, central nervous system function, hepatic function, renal function, nutritional status, extent of operative trauma, and course of anesthesia. Modified POSSUM (M-POSSUM) was developed using significant risk factors with its efficacy evaluated. RESULTS: The significant risk factors were found to be age, cardiovascular function, respiratory function, hepatic function, renal function, blood test results, endocrine function, nutritional status, duration of operation, intraoperative blood loss, and course of anesthesia. These factors were all included in the scoring system. There were significant differences in the scores between the patients with and without postoperative complications, between the patients died and survived with complications, and between the patients died and survived without complications. The receiver operating characteristic curves showed that the M-POSSUM could accurately predict postoperative complications and mortality.CONCLUSION: M-POSSUM correlates well with postoperative complications and mortality, and is more accurate than POSSUM. 展开更多
关键词 术后发病率 死亡率 术前评估 常规急救 级性疾病
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Agroecosystem functional assessment and its difficulties
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作者 CAOZhi-Ping RichardDawson 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第3期404-407,共4页
Agroecosystem functional assessment indicators provide a necessary bridge between decision makers and scientists. The development of acceptable indicators, however, remains a difficult task because the current knowle... Agroecosystem functional assessment indicators provide a necessary bridge between decision makers and scientists. The development of acceptable indicators, however, remains a difficult task because the current knowledge and understanding of ecosystems is not sufficient to allow an objective assessment of all ecosystem functions. These difficulties were summarized from three perspectives. First, there are difficulties in individual function assessment. Of the four functions associated with agroecosystems energy flow, materials cycling, information flow and value flow data on material cycling and information flow remain difficult to obtain and the indicators relatively immature. Secondly, there are difficulties of integration. During the assessment process, the integration of the agroecosystem functions remains the biggest obstacle. Until now, there has been no practical or effective methodology established to resolve the problem. At present, the makeshift approach has been to weight the various indicators and then add them together. Thirdly, there is the problem of obscure concepts and concept confusion. When assessments of agroecosystems are conducted, concepts such as structure, function, benefit, and resource utilization are used extensively. To date, no logical relationship(either real or implied) has been developed between any of these concepts. Are they causes and results such that the relationship between them is linear, or are they independent from one another such that the relationship is parallel? Thus far, the essence of this question is yet to be explored. 展开更多
关键词 functional assessment INDICATORS AGROECOSYSTEMS ecological benefit
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Treatment assessment of radiotherapy using MR functional quantitative imaging
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作者 Zheng Chang Chunhao Wang 《World Journal of Radiology》 CAS 2015年第1期1-6,共6页
Recent developments in magnetic resonance(MR) functional quantitative imaging have made it a potentially powerful tool to assess treatment response in radiation therapy. With its abilities to capture functional inform... Recent developments in magnetic resonance(MR) functional quantitative imaging have made it a potentially powerful tool to assess treatment response in radiation therapy. With its abilities to capture functional information on underlying tissue characteristics, MR functional quantitative imaging can be valuable in assessing treatment response and as such to optimize therapeutic outcome. Various MR quantitative imaging techniques, including diffusion weighted imaging, diffusion tensor imaging, MR spectroscopy and dynamic contrastenhanced imaging, have been investigated and found useful for assessment of radiotherapy. However, various aspects including data reproducibility, interpretation of biomarkers, image quality and data analysis impose challenges on applications of MR functional quantitative imaging in radiotherapy assessment. All of these challenging issues shall be addressed to help us understand whether MR functional quantitative imaging is truly beneficial and contributes to future development of radiotherapy. It is evident that individualized therapy is the future direction of patient care. MR functional quantitative imaging might serves as an indispensable tool towards this promising direction. 展开更多
关键词 MR functional QUANTITATIVE imaging Radiation therapy TREATMENT assessment
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Assessment of hindlimb motor recovery affer severe thoracic spinal cord injury in rats: classification of CatWalk XT■ gait analysis parameters 被引量:1
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作者 Guoli Zheng Hao Zhang +6 位作者 Mohamed Tail Hao Wang Johannes Walter Thomas Skutella Andreas Unterberg Klaus Zweckberger Alexander Younsi 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第5期1084-1089,共6页
Assessment of locomotion recovery in preclinical studies of experimental spinal cord injury remains challenging. We studied the CatWalk XT■gait analysis for evaluating hindlimb functional recovery in a widely used an... Assessment of locomotion recovery in preclinical studies of experimental spinal cord injury remains challenging. We studied the CatWalk XT■gait analysis for evaluating hindlimb functional recovery in a widely used and clinically relevant thoracic contusion/compression spinal cord injury model in rats. Rats were randomly assigned to either a T9 spinal cord injury or sham laminectomy. Locomotion recovery was assessed using the Basso, Beattie, and Bresnahan open field rating scale and the CatWalk XT■gait analysis. To determine the potential bias from weight changes, corrected hindlimb(H) values(divided by the unaffected forelimb(F) values) were calculated. Six weeks after injury, cyst formation, astrogliosis, and the deposition of chondroitin sulfate glycosaminoglycans were assessed by immunohistochemistry staining. Compared with the baseline, a significant spontaneous recovery could be observed in the CatWalk XT■parameters max intensity, mean intensity, max intensity at%, and max contact mean intensity from 4 weeks after injury onwards. Of note, corrected values(H/F) of CatWalk XT■parameters showed a significantly less vulnerability to the weight changes than absolute values, specifically in static parameters. The corrected CatWalk XT■parameters were positively correlated with the Basso, Beattie, and Bresnahan rating scale scores, cyst formation, the immunointensity of astrogliosis and chondroitin sulfate glycosaminoglycan deposition. The CatWalk XT■gait analysis and especially its static parameters, therefore, seem to be highly useful in assessing spontaneous recovery of hindlimb function after severe thoracic spinal cord injury. Because many CatWalk XT■parameters of the hindlimbs seem to be affected by body weight changes, using their corrected values might be a valuable option to improve this dependency. 展开更多
关键词 Basso Beattie and Bresnahan rating scale behavioral assessment CatWalk XT■gait analysis contusive and compressive injury hindlimb motor function histological changes spinal cord injury spontaneous recovery THORACIC weight
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An Exploratory Investigation of Difficulties in Applying Functional Behavior Assessment and Implementing Behavioral Intervention Plans in ADHD Programs in Saudi Arabia
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作者 Abdulrahman Abdullah Abaoud 《International Journal of Mental Health Promotion》 2022年第4期595-601,共7页
Functional behavior assessment(FBA)and behavioral intervention plans(BIPs)can be effective for students with attention deficit hyperactivity disorder(ADHD);however,teachers may face difficulties when implementing FBA pr... Functional behavior assessment(FBA)and behavioral intervention plans(BIPs)can be effective for students with attention deficit hyperactivity disorder(ADHD);however,teachers may face difficulties when implementing FBA procedures and,in turn,BIPs because of lack of time,insufficient training,and multiplicity of beliefs.Thus,it is important to identify the difficulties teachers may face and the obstacles that can deter them from implementing intervention plans.This is a worthwhile endeavor because nearly all classrooms will have students with behavioral problems who will benefit from specifically designed educational interventions.This study aimed to identify the difficulties in applying FBA and the barriers in implementing BIPs among Saudi teachers in specialized ADHD programs.Using the descriptive-analytical approach,a questionnaire targeting difficulties and barriers was admi-nistered to 209 public school teachers from specialized ADHD programs in Saudi Arabia.The results revealed that the difficulty level of applying FBA in ADHD programs was high.The level of barriers in implementing BIPs was moderate.Finally,the study indicated that barriers in implementing BIPs could be predicted by the difficulties of applying FBA.The results suggest the importance offinding better practices,restructuring the provision of ADHD programs,training teachers,improving assessment tool availability,and ensuring cooperation between school administrators and teachers. 展开更多
关键词 functional behavior assessment(FBA) behavioral intervention plans(BIPs) attention deficit hyperactivity disorder(ADHD) Saudi Arabia
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A Preliminary Exploration of the Functional Value Assessment of Ecosystem Services in Aral City
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作者 Guona Luo Xiancan Li +2 位作者 Shuang Liu Muhang Li Shuya Zhang 《Journal of Atmospheric Science Research》 2022年第1期18-24,共7页
Using the principles and methods of eco-economics as the research object,Aral City comprehensively expounds the ecological service functions such as ecosystem regulation of climate,carbon sequestration,soil conservati... Using the principles and methods of eco-economics as the research object,Aral City comprehensively expounds the ecological service functions such as ecosystem regulation of climate,carbon sequestration,soil conservation,water conservation and purification environment,and evaluates its economic value.The total value of the estimated 2021 is 1303.65 million yuan.At the same time,the importance of ecological service functions of urban ecosystems,from large to small,is to sequester carbon and release oxygen,purify the environment,maintain soil,conserd water sources,regulate the climate.The ecosystem service function which needs to be paid attention to in the concept of ecological construction and restoration of the next stage of ecological construction in Aral City. 展开更多
关键词 City of Aral Ecosystem services function Economic value assessment
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Seismic loss assessment of RC high-rise buildings designed according to Eurocode 8
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作者 Jelena Pejovic Nina Serdar 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第3期807-824,共18页
A probabilistic seismic loss assessment of RC high-rise(RCHR)buildings designed according to Eurocode 8 and located in the Southern Euro-Mediterranean zone is presented herein.The loss assessment methodology is based ... A probabilistic seismic loss assessment of RC high-rise(RCHR)buildings designed according to Eurocode 8 and located in the Southern Euro-Mediterranean zone is presented herein.The loss assessment methodology is based on a comprehensive simulation approach which takes into account ground motion(GM)uncertainty,and the random effects in seismic demand,as well as in predicting the damage states(DSs).The methodology is implemented on three RCHR buildings of 20-story,30-story and 40-story with a core wall structural system.The loss functions described by a cumulative lognormal probability distribution are obtained for two intensity levels for a large set of simulations(NLTHAs)based on 60 GM records with a wide range of magnitude(M),distance to source(R)and different site soil conditions(SS).The losses expressed in percent of building replacement cost for RCHR buildings are obtained.In the estimation of losses,both structural(S)and nonstructural(NS)damage for four DSs are considered.The effect of different GM characteristics(M,R and SS)on the obtained losses are investigated.Finally,the estimated performance of the RCHR buildings are checked to ensure that they fulfill limit state requirements according to Eurocode 8. 展开更多
关键词 RC high-rise buildings seismic loss assessment loss functions nonlinear time-history analysis(NLTHA) cumulative lognormal probability distribution random effects Eurocode 8
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A systemic functional approach to EFL writing assessment
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作者 LI Qing-feng 《Sino-US English Teaching》 2010年第8期5-9,共5页
关键词 英语教学 教学方法 阅读 中国 美国
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食用菌多糖结构与功能研究进展
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作者 冯翠萍 乔瑶瑶 +8 位作者 李佳欣 梁国栋 云少君 曹谨玲 程艳芬 程菲儿 常明昌 孟俊龙 刘靖宇 《山西农业科学》 2024年第2期128-144,共17页
食用菌具有较高的营养价值和功能价值,多糖作为食用菌最主要的活性成分之一,不仅能够为机体供给能量,而且可以参与生物合成反应及细胞的各项生命活动。大多数食用菌多糖是α-葡聚糖、β-葡聚糖、混合α,β-葡聚糖,以及由果糖、半乳糖、... 食用菌具有较高的营养价值和功能价值,多糖作为食用菌最主要的活性成分之一,不仅能够为机体供给能量,而且可以参与生物合成反应及细胞的各项生命活动。大多数食用菌多糖是α-葡聚糖、β-葡聚糖、混合α,β-葡聚糖,以及由果糖、半乳糖、甘露糖等多种单糖组成的杂多糖,其中,β-葡聚糖是食用菌中最具生物活性的多糖。食用菌多糖具有多种生物活性。为了为食用菌多糖在功能性食品中的应用提供理论基础,综述了食用菌多糖的结构及其抗氧化、抗衰老、调节免疫、抗炎、抗肿瘤、降血糖、降血脂、抗病毒、抗辐射、抗突变、抑菌、抗疲劳、抗凝血等方面的功能及机理,并对其进行了展望。 展开更多
关键词 食用菌 多糖 结构 生理功能
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新型冠状病毒感染后潜水员适潜性评估
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作者 官振标 董宇超 +4 位作者 徐佳骏 俞旭华 文宇坤 刘霞 刘文武 《海军军医大学学报》 CAS CSCD 北大核心 2024年第3期352-357,共6页
新型冠状病毒感染(COVID-19)对全身几乎所有器官都会产生影响,其中最主要的受累器官为肺和心脏。随着COVID-19康复患者数量不断增加,越来越多的证据表明,因COVID-19住院治疗获得康复的患者中有相当大比例的人群存在后遗症,主要表现为呼... 新型冠状病毒感染(COVID-19)对全身几乎所有器官都会产生影响,其中最主要的受累器官为肺和心脏。随着COVID-19康复患者数量不断增加,越来越多的证据表明,因COVID-19住院治疗获得康复的患者中有相当大比例的人群存在后遗症,主要表现为呼吸系统和心血管系统的症状。对于潜水员,COVID-19后的运动耐受、心肺功能的恢复对其适潜性具有重要影响。一些组织和机构发布了潜水员COVID-19后的适潜性评估指南。本文对COVID-19后的呼吸和心血管系统后遗症及相关的适潜性评估方案进行简要介绍,并基于已有的相关要求和我国实际,初步提出我国潜水员COVID-19后的适潜性评估要求。 展开更多
关键词 新型冠状病毒感染 适潜性 评估 肺功能 运动耐受 心功能
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采用三次样条函数拟合蚊媒密度概率分布及其风险评估
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作者 曾四清 邓惠 +4 位作者 段金花 陈宗晶 芦瑞鹏 刘礼平 吴军 《中国卫生统计》 CSCD 北大核心 2024年第3期414-418,共5页
目的研究登革热蚊媒MOI风险的概率分布,为更加科学精准开展MOI风险评估提供新方法。方法采用三次样条函数、累积概率分布和Python语言编程对广州市2016—2019年各月MOI监测数据进行拟合分析。结果本研究绘制了广州市1-12月的MOI风险评... 目的研究登革热蚊媒MOI风险的概率分布,为更加科学精准开展MOI风险评估提供新方法。方法采用三次样条函数、累积概率分布和Python语言编程对广州市2016—2019年各月MOI监测数据进行拟合分析。结果本研究绘制了广州市1-12月的MOI风险评估概率分布表和分布图。1-12月各月累积概率小于0.01和0.05的MOI临界值分别在7.54~60.12、5.02~34.10之间。该临界值均在1月最低,其次是12月和2月;均在6月份最高,其次是5月和7月。1-12月各月MOI风险等级为传播、暴发和流行的概率分别在5.07%~66.60%、0.25%~36.19%、0.00%~16.80%之间。传播、暴发和流行的风险概率最低值均出现在1月,其次均在2月;最高值分别出现在7月、7月和6月,其次是6月、6月和5月。结论广州市各月的MOI风险概率分布具有显著的季节性消长规律和特征,在开展登革热蚊媒监测评估与控制工作中值得重视。三次样条函数和累积概率分布拟合法为开展MOI风险评估提供了新的分析方法。 展开更多
关键词 诱蚊诱卵指数 风险评估 三次样条函数 概率分布
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贮藏温度对火棘鲜果采后生理及功效活性成分的影响
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作者 陈一龙 商桑 +4 位作者 曾顺德 曾小峰 刁源 尹旭敏 高伦江 《食品研究与开发》 CAS 2024年第8期91-96,103,共7页
以重庆彭水野生火棘鲜果为试材,研究贮藏温度对火棘功效活性成分原花青素、黄酮、总酚和VC含量的影响,分析相关抗性酶超氧化物歧化酶(superoxide dismutase,SOD)、苯丙氨酸解氨酶(shenylalanine ammonia lyase,PAL)活性和次生代谢产物... 以重庆彭水野生火棘鲜果为试材,研究贮藏温度对火棘功效活性成分原花青素、黄酮、总酚和VC含量的影响,分析相关抗性酶超氧化物歧化酶(superoxide dismutase,SOD)、苯丙氨酸解氨酶(shenylalanine ammonia lyase,PAL)活性和次生代谢产物丙二醛(malondialdehyde,MDA)含量及腐损率变化趋势。结果表明:-5、-3、-1、1、3、5℃贮藏60 d原花青素保持率分别是初始含量的72.97%、65.43%、48.12%、29.76%、21.33%和19.22%;黄酮保持率分别为77.25%、76.27%、72.01%、60.39%、56.96%和35.19%;总酚保持率分别为83.66%、82.61%、62.80%、55.69%、48.51%和43.11%;VC保持率分别为87.17%、86.43%、75.46%、54.83%、36.06%和24.35%;SOD活性保持率分别为81.56%、79.78%、66.32%、27.86%、15.83%和11.25%;PAL活性保持率分别为57.43%、50.05%、42.00%、19.69%、15.62%和14.12%;MDA累积程度与初始含量相比,分别为2.19、2.59、4.51、6.52、7.52倍和8.54倍;腐损率与5℃贮藏60 d相比,分别低88.10%、87.94%、81.09%、54.25%和12.53%。-5、-3℃贮藏与5、3、1、-1℃贮藏相比均可有效保持原有功效成分、降低腐损率、减少MDA累积程度、保持较高SOD和PAL活性,但-5℃和-3℃贮藏差异不显著,-3℃可作为优选贮藏温度。 展开更多
关键词 贮藏温度 火棘鲜果 采后生理 功效活性 影响
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矢车菊-3-葡萄糖苷提取纯化、生物活性及稳态化技术的研究进展
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作者 高琦 孙铭阳 +3 位作者 袁兴铃 彭雪 王宁 薛友林 《现代食品科技》 CAS 北大核心 2024年第6期318-326,共9页
矢车菊-3-葡萄糖苷(Cyanidin-3-glucoside,C3G)是自然界中分布最为广泛的一种花青素,富含于水果、蔬菜和谷物中,具有抗氧化、抗癌、抗炎以及维持视觉健康等生理功能,在食品、医药等行业备受关注。提取纯化是利用C3G的重要步骤,但C3G在... 矢车菊-3-葡萄糖苷(Cyanidin-3-glucoside,C3G)是自然界中分布最为广泛的一种花青素,富含于水果、蔬菜和谷物中,具有抗氧化、抗癌、抗炎以及维持视觉健康等生理功能,在食品、医药等行业备受关注。提取纯化是利用C3G的重要步骤,但C3G在储存、加工过程中易受外界环境的影响而失去原有的颜色和生理价值。为促进C3G在食品领域的应用,该文汇总了C3G在不同食物中的含量及常见的提取纯化方法,概述了C3G抗氧化、抗癌、抗炎以及维持视觉健康等生物活性,并从生物大分子复合和分子修饰两个方面介绍了C3G的稳态化方法,为未来研究和综合开发利用C3G提供理论依据。 展开更多
关键词 矢车菊-3-葡萄糖苷 提取 纯化 生理功能 稳定性保持
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北京八达岭林场人工林生态服务功能评估
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作者 毛军 王立平 +6 位作者 高永龙 姚永刚 隗骥超 李卫兵 田赟 刘鹏 查天山 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期224-232,共9页
人工林生态服务功能评估是应用生态学领域研究的热点,也是数字生态和林业高质量发展的需求.本文以北京市八达岭林场人工林生态系统(混交林、针叶林、阔叶林)和天然灌木林为研究对象,以北京市森林资源规划设计调查资料(2004、2009、2014... 人工林生态服务功能评估是应用生态学领域研究的热点,也是数字生态和林业高质量发展的需求.本文以北京市八达岭林场人工林生态系统(混交林、针叶林、阔叶林)和天然灌木林为研究对象,以北京市森林资源规划设计调查资料(2004、2009、2014年)和八达岭林场碳通量实时监测为基础数据源,通过野外调查及典型样方观测,开展人工林生态服务功能评价,旨在探究森林生态系统结构优化和功能提升的森林经营建议.结果表明:1)2004−2014年八达岭林场针叶林和灌木林面积增长率分别为40.48%和3.32%,而阔叶林和混交林分别减少46.33%和3.57%,林场仍以混交林(703 hm^(2))和灌木林(1182 hm^(2))为主.2)2004−2014年阔叶林中椴树逐渐成为主要树种,2014年涵养水源量较2009年提高了1.55倍.油松作为混交林的优势树种,其涵养水源实物量2014年较2004年提高了67%.灌木林在2014年出现了较大幅度增加,涵养水源实物量较2004年提高了1倍左右,其价值量也相应增加.固碳、释氧、提供负氧离子、滞尘和吸收污染物等调节服务功能及其价值均表现为混交林最高,针叶林次之,阔叶林最低(P>0.05);各林分服务功能价值量与功能实物量变化趋势相同,灌木林固土和保肥功能优于其余3种林分,混交林和针叶林营养物质累积量和生物多样性优于阔叶林.3)2004−2014年保育土壤(92.91%)、生物多样性保护(4.33%)及涵养水源功能(2.33%)对人工林生态服务功能的贡献率大于固碳释氧(0.37%)、森林防护(0.04%)和净化大气环境(0.02%)功能,其中混交林和针叶林对人工林生态服务功能贡献大于阔叶林和灌木林.由此可见,林分类型和林分面积是影响人工林生态服务功能强弱的主要决定因素.八达岭人工林经营应持续保持保育土壤功能,在保证生物多样性的情况下,应注重固碳增汇功能,建议将现有林分多调整为混交林和灌木林,营造“异龄、复层”的理想人工林生态系统,逐渐提高北京八达岭人工林生态服务功能. 展开更多
关键词 人工林 生态系统 生态服务功能 价值评估 固碳增汇
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外源钙对甘草生长及生理特性的影响
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作者 安钰 张清云 +1 位作者 李生兵 王东清 《甘肃农业大学学报》 CAS CSCD 北大核心 2024年第1期185-193,共9页
【目的】为揭示宁夏中部干旱带甘草优质高产栽培过程中甘草对不同钙浓度的适应机制,探究了外源钙对甘草生长及生理生化特性的影响。【方法】以乌拉尔甘草为试验材料,设置0(CK)、5(G_(1))、10(G_(2))、15(G_(3))、20 mmol/L(G_(4))5个钙... 【目的】为揭示宁夏中部干旱带甘草优质高产栽培过程中甘草对不同钙浓度的适应机制,探究了外源钙对甘草生长及生理生化特性的影响。【方法】以乌拉尔甘草为试验材料,设置0(CK)、5(G_(1))、10(G_(2))、15(G_(3))、20 mmol/L(G_(4))5个钙浓度,分析比较了不同浓度外源钙处理下甘草生长、光合特性及抗氧化酶活性的变化,同时采用主成分分析和隶属函数法综合评价出适宜甘草生长的外源钙施用浓度。【结果】随着钙浓度的增加,甘草主根长、主根直径、单根鲜质量呈先增加后下降的趋势,且不同处理之间差异不显著;甘草叶片叶绿素含量、净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、胞间CO_(2)浓度(Ci)、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、过氧化物酶(POD)活性整体呈现先升后降的趋势,钙浓度为10 mmol/L时,Tr、Pn、Gs、SOD活性、CAT活性均达到峰值,且Pn、Gs显著高于对照(P<0.05)。MDA含量随着钙浓度的增加呈先下降后上升的趋势,各浓度处理间差异显著(P<0.05),钙浓度为10mmol/L时的MDA含量最低。综合评价结果表明,钙浓度为10mmol/L时,隶属函数值的均值最大,为0.739。【结论】施用外源钙有利于改善甘草的生理生化特性,促进生长发育;10mmol/L钙浓度是甘草生长的最佳施用量,可为干旱地区甘草的栽培模式提供理论依据。 展开更多
关键词 甘草 外源钙 生理特性 隶属函数法 主成分分析
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聊城市农田土壤污染评价及农业功能分区
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作者 王岩 王倩 +1 位作者 田晓飞 郭琳 《山东农业大学学报(自然科学版)》 北大核心 2024年第2期184-192,共9页
为探索聊城市农田土壤污染状况及农业功能分区,以2017~2020年采集的74个表层土样为研究对象,测定了8种重金属元素(Cd、Hg、As、Cu、Pb、Cr、Zn和Ni)、BHC_(s)、DDT_(s)和BaP的含量。依据《土壤环境质量农用地土壤污染风险管控标准》和... 为探索聊城市农田土壤污染状况及农业功能分区,以2017~2020年采集的74个表层土样为研究对象,测定了8种重金属元素(Cd、Hg、As、Cu、Pb、Cr、Zn和Ni)、BHC_(s)、DDT_(s)和BaP的含量。依据《土壤环境质量农用地土壤污染风险管控标准》和《绿色食品产地环境质量》作为评价标准,采用污染指数法开展了土壤环境质量评价和农业功能分区研究。采用ANOVA和LSD多重比较,确定了污染物的空间分布差异及其来源。依据山东省土壤背景值进行了重金属潜在生态风险评价。结果表明,除3个DDTs污染样点和1个Cd污染样点外,其他样点均处于清洁水平。在空间分布上,DDTs和Cr含量存在极显著差异,BaP和Hg存在显著差异。农业功能分区结果表明,绿色食品种植区、无公害食品种植区、观察种植区和污染区面积分别占研究区总面积的78.13%、9.45%、6.52%和5.90%。土壤环境生态风险水平以轻微为主,占总面积的77.03%。Hg和Cd在生态风险评估中占有较大比率,应高度警惕和严格监管。 展开更多
关键词 重金属 有机污染物 轻微污染 生态风险评价 农业功能分区
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人参副产物在动物生产中的应用研究进展
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作者 徐明磊 孙亚楠 陈双林 《饲料研究》 CAS 北大核心 2024年第1期167-170,共4页
人参副产物主要包括人参渣以及未被利用的人参茎叶、花果及根须等,富含人参皂苷、人参多糖等活性物质,具有提高免疫力、抗疲劳、抑菌及抗病毒等多种生物学功能。目前人参副产物主要作为废弃物进行处理,不仅未能充分发挥其功效,还造成了... 人参副产物主要包括人参渣以及未被利用的人参茎叶、花果及根须等,富含人参皂苷、人参多糖等活性物质,具有提高免疫力、抗疲劳、抑菌及抗病毒等多种生物学功能。目前人参副产物主要作为废弃物进行处理,不仅未能充分发挥其功效,还造成了资源浪费。人参副产物在动物生产中具有良好的应用前景,其中人参渣和人参茎叶可作为日粮成分或添加剂,人参茎叶中的人参皂苷还可作为动物疫苗佐剂。文章综述了人参副产物的生物学功能及其在动物生产中的应用现状,为提高人参副产物的综合利用及动物生产性能提供参考。 展开更多
关键词 人参副产物 生物功能 生理调控 动物生产
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立德树人视域下高级植物生理学核心课程设计与实践
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作者 郭晓红 汪秀志 +2 位作者 鞠世杰 郭景茹 于立红 《黑龙江农业科学》 2024年第7期87-91,共5页
核心课程的建设在研究生教育中起到至关重要的作用。本文以高级植物生理学为例,分析该课程在研究生培养中的地位和作用。坚持以“立德树人”为人才培养核心理念,提出了核心课程建设思路。该思路将思政育人贯穿于课程教学始终,通过引入... 核心课程的建设在研究生教育中起到至关重要的作用。本文以高级植物生理学为例,分析该课程在研究生培养中的地位和作用。坚持以“立德树人”为人才培养核心理念,提出了核心课程建设思路。该思路将思政育人贯穿于课程教学始终,通过引入国家级精品课程、相关教学视频、原创教学资源、最新科研成果等,构建了线上教学资源。采用线上线下混合式教学模式,通过全过程评价和多元化考核方式提升了教学质量。通过以上课程建设,将专业知识与思政教育有机融合,有效地提升研究生的综合素质。 展开更多
关键词 高级植物生理学 立德树人 线上线下混合式教学模式 多元化考核
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