期刊文献+
共找到4,447篇文章
< 1 2 223 >
每页显示 20 50 100
Analysis of Distribution of Public Toilets within Walking Range around Communities of the Elderly under the Model of Community Home-based Care for the Elderly: A Case Study of Changxindian, Fengtai District, Beijing
1
作者 TIAN Jiaqi ZHANG Miao HU Yan 《Journal of Landscape Research》 2024年第2期35-37,41,共4页
In recent years,under the influence of multiple factors such as traditional ideas and living economic conditions,the aging population in China continues to increase.Most of the elderly are more inclined to aged at hom... In recent years,under the influence of multiple factors such as traditional ideas and living economic conditions,the aging population in China continues to increase.Most of the elderly are more inclined to aged at home,and the first places for elderly activities are communities and the surrounding environment,which greatly affects the convenience of life and happiness of the elderly.In this paper,Changxindian area in Fengtai District of Beijing was as the research object,and detailed calculation and analysis were carried out by using POI data and arcGIS software.The relative location of residential areas and surrounding public toilets was explored,and the best location of public toilets in the daily walking area under the model of community home-based care for the elderly was further studied. 展开更多
关键词 Home-based care for the elderly The elderly Public toilets community
下载PDF
E-learning在医学教育领域内的实践与研究
2
作者 董慧琳 仇菲 《中国医药导报》 CAS 2023年第25期77-80,共4页
科学技术与医学教育的发展,对医学教育的过程及途径提出新要求。电子学习(E-learning)作为一种新型教学方式,早已在教育、培训等领域广泛应用,尤其是在国外。在国内医学教育领域中,E-learning也得到迅速发展,并发挥积极作用。随着这种... 科学技术与医学教育的发展,对医学教育的过程及途径提出新要求。电子学习(E-learning)作为一种新型教学方式,早已在教育、培训等领域广泛应用,尤其是在国外。在国内医学教育领域中,E-learning也得到迅速发展,并发挥积极作用。随着这种应用趋势的展开,不少学者对此进行相关研究。本文在对E-learning方式进行解读的基础上,追溯其发展历程与在医学教育领域内的应用现状,对相关的国内外研究资料进行回顾,为E-learning在国内医学教育的实践研究提供建设性启示。 展开更多
关键词 e-learning 医学教育 教学改革 自主学习
下载PDF
基于E-learning的翻转课堂模式在消化系统疾病实习教学中的应用效果 被引量:1
3
作者 李健 高建淑 +1 位作者 赵可可 高鸿亮 《新疆医科大学学报》 CAS 2023年第10期1408-1410,共3页
目的 探讨基于E-learning的翻转课堂模式在消化系统疾病实习教学中的应用效果。方法 选取2021年8月至2022年7月在新疆医科大学第一临床医学院就读的200名临床医学专业学生,采用随机数字表法分为研究组(100名)与对照组(100名)。研究组采... 目的 探讨基于E-learning的翻转课堂模式在消化系统疾病实习教学中的应用效果。方法 选取2021年8月至2022年7月在新疆医科大学第一临床医学院就读的200名临床医学专业学生,采用随机数字表法分为研究组(100名)与对照组(100名)。研究组采用基于E-learning的翻转课堂模式教学,对照组实施传统教学模式教学。比较两组学生自我评价、教师对学生能力评价以及理论考核和临床操作考核成绩。结果 研究组学生学习兴趣、学习效率、学习信心、总体满意度的自我评价均高于对照组(P均<0.05);带教教师对研究组学生自主学习能力、团队协作能力、临床思维能力、临床技能能力评价均高于对照组(P均<0.05);研究组学生理论考核和临床操作考核成绩均高于对照组(P均<0.05)。结论 基于E-learning的翻转课堂模式可有效培养学生临床思维和操作能力,提升消化系统疾病实习教学效率及教学效果。 展开更多
关键词 e-learning 翻转课堂 传统教学 消化系统疾病 实习教学
下载PDF
Insights into microbiota community dynamics and flavor development mechanism during golden pomfret(Trachinotus ovatus)fermentation based on single-molecule real-time sequencing and molecular networking analysis 被引量:1
4
作者 Yueqi Wang Qian Chen +5 位作者 Huan Xiang Dongxiao Sun-Waterhouse Shengjun Chen Yongqiang Zhao Laihao Li Yanyan Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期101-114,共14页
Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain unclear.This study shows the roles of the ... Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain unclear.This study shows the roles of the complex microbiota and the dynamic changes in microbial community and flavor compounds during fish fermentation.Single-molecule real-time sequencing and molecular networking analysis revealed the correlations among different microbial genera and the relationships between microbial taxa and volatile compounds.Mechanisms underlying flavor development were also elucidated via KEGG based functional annotations.Clostridium,Shewanella,and Staphylococcus were the dominant microbial genera.Forty-nine volatile compounds were detected in the fermented fish samples,with thirteen identified as characteristic volatile compounds(ROAV>1).Volatile profiles resulted from the interactions among the microorganisms and derived enzymes,with the main metabolic pathways being amino acid biosynthesis/metabolism,carbon metabolism,and glycolysis/gluconeogenesis.This study demonstrated the approaches for distinguishing key microbiota associated with volatile compounds and monitoring the industrial production of high-quality fermented fish products. 展开更多
关键词 Fermented golden pomfret Microbiota community Volatile compound Co-occurrence network Metabolic pathway
下载PDF
Blockchain-Based Decentralized Authentication Model for IoT-Based E-Learning and Educational Environments
5
作者 Osama A.Khashan Sultan Alamri +3 位作者 Waleed Alomoush Mutasem K.Alsmadi Samer Atawneh Usama Mir 《Computers, Materials & Continua》 SCIE EI 2023年第5期3133-3158,共26页
In recent times,technology has advanced significantly and is currently being integrated into educational environments to facilitate distance learning and interaction between learners.Integrating the Internet of Things... In recent times,technology has advanced significantly and is currently being integrated into educational environments to facilitate distance learning and interaction between learners.Integrating the Internet of Things(IoT)into education can facilitate the teaching and learning process and expand the context in which students learn.Nevertheless,learning data is very sensitive and must be protected when transmitted over the network or stored in data centers.Moreover,the identity and the authenticity of interacting students,instructors,and staff need to be verified to mitigate the impact of attacks.However,most of the current security and authentication schemes are centralized,relying on trusted third-party cloud servers,to facilitate continuous secure communication.In addition,most of these schemes are resourceintensive;thus,security and efficiency issues arise when heterogeneous and resource-limited IoT devices are being used.In this paper,we propose a blockchain-based architecture that accurately identifies and authenticates learners and their IoT devices in a decentralized manner and prevents the unauthorized modification of stored learning records in a distributed university network.It allows students and instructors to easily migrate to and join multiple universities within the network using their identity without the need for user re-authentication.The proposed architecture was tested using a simulation tool,and measured to evaluate its performance.The simulation results demonstrate the ability of the proposed architecture to significantly increase the throughput of learning transactions(40%),reduce the communication overhead and response time(26%),improve authentication efficiency(27%),and reduce the IoT power consumption(35%)compared to the centralized authentication mechanisms.In addition,the security analysis proves the effectiveness of the proposed architecture in resisting various attacks and ensuring the security requirements of learning data in the university network. 展开更多
关键词 Blockchain decentralized authentication Internet of Things(IoT) e-learning IoT security
下载PDF
Real Objects Understanding Using 3D Haptic Virtual Reality for E-Learning Education
6
作者 Samia Allaoua Chelloug Hamid Ashfaq +4 位作者 Suliman A.Alsuhibany Mohammad Shorfuzzaman Abdulmajeed Alsufyani Ahmad Jalal Jeongmin Park 《Computers, Materials & Continua》 SCIE EI 2023年第1期1607-1624,共18页
In the past two decades,there has been a lot of work on computer vision technology that incorporates many tasks which implement basic filtering to image classification.Themajor research areas of this field include obj... In the past two decades,there has been a lot of work on computer vision technology that incorporates many tasks which implement basic filtering to image classification.Themajor research areas of this field include object detection and object recognition.Moreover,wireless communication technologies are presently adopted and they have impacted the way of education that has been changed.There are different phases of changes in the traditional system.Perception of three-dimensional(3D)from two-dimensional(2D)image is one of the demanding tasks.Because human can easily perceive but making 3D using software will take time manually.Firstly,the blackboard has been replaced by projectors and other digital screens so such that people can understand the concept better through visualization.Secondly,the computer labs in schools are now more common than ever.Thirdly,online classes have become a reality.However,transferring to online education or e-learning is not without challenges.Therefore,we propose a method for improving the efficiency of e-learning.Our proposed system consists of twoand-a-half dimensional(2.5D)features extraction using machine learning and image processing.Then,these features are utilized to generate 3D mesh using ellipsoidal deformation method.After that,3D bounding box estimation is applied.Our results show that there is a need to move to 3D virtual reality(VR)with haptic sensors in the field of e-learning for a better understanding of real-world objects.Thus,people will have more information as compared to the traditional or simple online education tools.We compare our result with the ShapeNet dataset to check the accuracy of our proposed method.Our proposed system achieved an accuracy of 90.77%on plane class,85.72%on chair class,and car class have 72.14%.Mean accuracy of our method is 70.89%. 展开更多
关键词 Artificial intelligence e-learning online education system computer vision virtual reality 3D haptic
下载PDF
Student’s Health Exercise Recognition Tool for E-Learning Education
7
作者 Tamara al Shloul Madiha Javeed +4 位作者 Munkhjargal Gochoo Suliman AAlsuhibany Yazeed Yasin Ghadi Ahmad Jalal Jeongmin Park 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期149-161,共13页
Due to the recently increased requirements of e-learning systems,multiple educational institutes such as kindergarten have transformed their learning towards virtual education.Automated student health exercise is a di... Due to the recently increased requirements of e-learning systems,multiple educational institutes such as kindergarten have transformed their learning towards virtual education.Automated student health exercise is a difficult task but an important one due to the physical education needs especially in young learners.The proposed system focuses on the necessary implementation of student health exercise recognition(SHER)using a modified Quaternion-basedfilter for inertial data refining and data fusion as the pre-processing steps.Further,cleansed data has been segmented using an overlapping windowing approach followed by patterns identification in the form of static and kinematic signal patterns.Furthermore,these patterns have been utilized to extract cues for both patterned signals,which are further optimized using Fisher’s linear discriminant analysis(FLDA)technique.Finally,the physical exercise activities have been categorized using extended Kalmanfilter(EKF)-based neural networks.This system can be implemented in multiple educational establishments including intelligent training systems,virtual mentors,smart simulations,and interactive learning management methods. 展开更多
关键词 e-learning exercise recognition online physical education student’s healthcare
下载PDF
Delineation of an Urban Community Life Circle Based on a Machine-Learning Estimation of Spatiotemporal Behavioral Demand 被引量:3
8
作者 LI Chunjiang XIA Wanqu CHAI Yanwei 《Chinese Geographical Science》 SCIE CSCD 2021年第1期27-40,共14页
Delineating life circles is an essential prerequisite for urban community life circle planning. Recent studies combined the environmental contexts with residents’ global positioning system(GPS) data to delineate the ... Delineating life circles is an essential prerequisite for urban community life circle planning. Recent studies combined the environmental contexts with residents’ global positioning system(GPS) data to delineate the life circles. This method, however, is constrained by GPS data, and it can only be applied in the GPS surveyed communities. To address this limitation, this study developed a generalizable delineation method without the constraint of behavioral data. According to previous research, the community life circle consists of the walking-accessible range and internal structure. The core task to develop the generalizable method was to estimate the spatiotemporal behavioral demand for each plot of land to acquire the internal structure of the life circle, as the range can be delineated primarily based on environmental data. Therefore, behavioral demand estimation models were established through logistic regression and machine learning techniques, including decision trees and ensemble learning. The model with the lowest error rate was chosen as the final estimation model for each type of land. Finally, we used a community without GPS data as an example to demonstrate the effectiveness of the estimation models and delineation method. This article extends the existing literature by introducing spatiotemporal behavioral demand estimation models, which learn the relationships between environmental contexts, population composition and the existing delineated results based on GPS data to delineate the internal structure of the community life circle without employing behavioral data. Furthermore, the proposed method and delineation results also contributes to facilities adjustments and location selections in life circle planning, people-oriented transformation in urban planning, and activity space estimation of the population in evaluating and improving the urban policies. 展开更多
关键词 community life circle spatiotemporal behavioral demand demand estimation model decision tree ensemble learning
下载PDF
Effects of Biostimulation-Bioaugmentation on Coastal Microbial Community in an in situ Mesocosm System
9
作者 YUAN Fangzheng ZHAO Yangyong +2 位作者 DAI Yulai YANG Wen ZHU Jinyong 《Journal of Ocean University of China》 CAS CSCD 2024年第1期233-246,共14页
Globally,various types of pollution affect coastal waters as a result of human activities.Bioaugmentation and biostimulation are effective methods for treating water pollution.However,few studies have explored the res... Globally,various types of pollution affect coastal waters as a result of human activities.Bioaugmentation and biostimulation are effective methods for treating water pollution.However,few studies have explored the response of coastal prokaryotic and eukaryotic communities to bioaugmentation and biostimulation.Here,a 28-day outdoor mesocosm experiment with two treatments(bioaugmentation-A and combined treatment of bioaugmentation and biostimulation-AS)and a control(untreated-C)were carried out.The experiment was conducted in Meishan Bay to explore the composition,dynamics,and co-occurrence patterns of prokaryotic and eukaryotic communities in response to the A and AS using 16S rRNA and 18S rRNA gene amplicon sequencing.After treatment,Gammaproteobacteria and Epsilonproteobacteria were significantly increased in group AS compared to group C,while Flavobacteriia and Saprospirae were significantly reduced.Dinoflagellata was significantly reduced in AS compared to C,while Chrysophyta was significantly reduced in both AS and A.Compared to C,the principal response curve analyses of the prokaryotic and eukaryotic communities both showed an increasing trend followed by a decreasing trend for AS.Furthermore,the trends of prokaryotic and eukaryotic communities in group A were similar to those in group AS compared with group C,but AS changed them more than A did.According to the species weight table on principal response curves,a significant increase was observed in beneficial bacteria in prokaryotic communities,such as Rhodobacterales and Oceanospirillales,along with a decrease in autotrophs in eukaryotic communities,such as Chrysophyta and Diatom.Topological properties of network analysis reveal that A and AS complicate the interactions between the prokaryotic and eukaryotic communities.Overall,these findings expand our understanding of the response pattern of the bioaugmentation and biostimulation on coastal prokaryotic and eukaryotic communities. 展开更多
关键词 prokaryotic community eukaryotic community BIOAUGMENTATION BIOSTIMULATION coastal waters
下载PDF
Sport Participation and Community Capacity Building in Disadvantaged Urban Communities
10
作者 Ivana Matteucci 《Journal of Sociology Study》 2023年第1期1-9,共9页
The aim of this study was to investigate the relationships between sport and community by examining the role played by sports participation in community engagement and community capacity building in disadvantaged urba... The aim of this study was to investigate the relationships between sport and community by examining the role played by sports participation in community engagement and community capacity building in disadvantaged urban communities.From a conceptual standpoint,the study is based on the sociological theory of the community and Community Capacity Building(CCB)theory,which provide overviews of the concept of community and community capacity and its characteristics.Four disadvantaged urban communities were investigated.Two of these communities had sports programs,while the other two did not.The online questionnaire methodology was adopted to assess the socio-demographic characteristics and community engagement of the participants(knowledge of programs and participation in community activities),and subsequently,an analysis of the online social media narratives of the community members themselves was developed to measure the characteristics of their community capacity building.We found that community engagement and community capacity values were higher in the communities with sports programs.These findings are promising and suggest that approaches based on sports participation development could be fruitful,particularly in disadvantaged communities. 展开更多
关键词 community engagement community capacity building SPORT disadvantaged community online narratives
下载PDF
Implication of community-level ecophysiological parameterization to modelling ecosystem productivity:a case study across nine contrasting forest sites in eastern China
11
作者 Minzhe Fang Changjin Cheng +2 位作者 Nianpeng He Guoxin Si Osbert Jianxin Sun 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期1-11,共11页
Parameterization is a critical step in modelling ecosystem dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations... Parameterization is a critical step in modelling ecosystem dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations often arise from inappropriate model parameterization.Here we compared five methods for defining community-level specific leaf area(SLA)and leaf C:N across nine contrasting forest sites along the North-South Transect of Eastern China,including biomass-weighted average for the entire plant community(AP_BW)and four simplified selective sampling(biomass-weighted average over five dominant tree species[5DT_BW],basal area weighted average over five dominant tree species[5DT_AW],biomass-weighted average over all tree species[AT_BW]and basal area weighted average over all tree species[AT_AW]).We found that the default values for SLA and leaf C:N embedded in the Biome-BGC v4.2 were higher than the five computational methods produced across the nine sites,with deviations ranging from 28.0 to 73.3%.In addition,there were only slight deviations(<10%)between the whole plant community sampling(AP_BW)predicted NPP and the four simplified selective sampling methods,and no significant difference between the predictions of AT_BW and AP_BW except the Shennongjia site.The findings in this study highlights the critical importance of computational strategies for community-level parameterization in ecosystem process modelling,and will support the choice of parameterization methods. 展开更多
关键词 BIOME-BGC community traits Forest Ecosystems Model parameterization
下载PDF
Assessment of the Characteristics of Demersal Fish Communities Using Species-and Trait-Based Approaches in the Coastal Habitats Along Rongcheng Bay,Shandong Peninsula,China
12
作者 YUAN Shunjie SUN Xin +3 位作者 TU Zhong SUN Jie WANG Xianning ZHANG Peidong 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期786-796,共11页
Biodiversity declines have motivated many studies on the relationship between species diversity and ecosystem functioning.In this study,we described the spatial-temporal characteristics of demersal fish communities al... Biodiversity declines have motivated many studies on the relationship between species diversity and ecosystem functioning.In this study,we described the spatial-temporal characteristics of demersal fish communities along a coastal habitat in Rongcheng Bay,Shandong Peninsula,China with both species-based and biological trait-based approaches.The field survey was carried out monthly using traps from April to October of 2018,and divided into three seasons(spring:April and May;summer:June,July and August;autumn:September,October and November).The study area included five distinct habitats:seagrass bed,natural rocky reef,bare sand,artificial reef together with natural rocky reef,and artificial reef together with bare sand.We analyzed the fish communities with three taxonomic diversity indices,including Shannon-Wiener,Simpson,and Pielou Evenness,as well as four functional diversity indices,including FRic,FEve,FDiv,and FDis,based on 7 functional groups which are categorized into 27 traits.The results showed that there were no significant differences in taxonomic diversity indices among different habitats in the three seasons.However,significant differences were found in the functional richness of fish communities among different habitats in three seasons.Seagrass bed represented the highest functional richness in spring and autumn.This study demonstrates that seagrass bed is very important in enhancing the functional diversity of fish communities in a complex habitat.The study also indicates that the combination of taxonomic diversity and functional diversity will provide a more detailed description of the characteristics of fish communities. 展开更多
关键词 complex habitat biological traits BIODIVERSITY fish communities
下载PDF
Physiological and psychological responses to tended plant communities with varying color characteristics
13
作者 Siyuan Zheng Yanzhen Zhou Haiyan Qu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期183-201,共19页
Exposure to plants has been reported to promote health and reduce stress,and plant color has direct impacts on physical and mental health.We used images of common types of tended plant communities in Shenyang,China,wi... Exposure to plants has been reported to promote health and reduce stress,and plant color has direct impacts on physical and mental health.We used images of common types of tended plant communities in Shenyang,China,with combinations of yellow,green,and red foliage,as experimental stimuli.A total of 27 images were used as visual stimuli.We used electroencephalography to measureαwave activity(8-13 Hz)in 40 subjects while they viewed visual stimuli.These data were combined with subjective questionnaire data to analyze the relaxing effect of images of tended plant communities with different color types and proportions on people.The results revealed that,although there were slight differences between the electroencephalography and psychological findings,women were significantly more relaxed than men after viewing the images.Physiological and psychological responses varied with the types and proportions of colors in the tended plant communities:those of foliage with combinations of two or three colors induced stronger responses than images with a single color.Specifically,(1)for one-color plant communities,green or yellow plant communities induced a stronger relaxation effect than red plant communities;(2)for two-color plant communities,the optimal color proportion was 55%+45%,and the green+yellow and green+red color combinations induced a stronger relaxation effect;(3)for three-color plant communities,the relaxation effect was strongest when the color proportion was 55%green+25%yellow+20%red.These data would provide a plant color matching in future plant landscape design,which may be helpful for creating healthy and relaxing environments. 展开更多
关键词 Plant community Color type Color ratio ELECTROENCEPHALOGRAPHY Subjective questionnaire
下载PDF
Manure substitution improves maize yield by promoting soil fertility and mediating the microbial community in lime concretion black soil
14
作者 Minghui Cao Yan Duan +6 位作者 Minghao Li Caiguo Tang Wenjie Kan Jiangye Li Huilan Zhang Wenling Zhong Lifang Wu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期698-710,共13页
Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidif... Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidification,groundwater contamination and biodiversity reduction.Meanwhile,organic substitution has received increasing attention for its ecologically and environmentally friendly and productivity benefits.However,the linkages between manure substitution,crop yield and the underlying microbial mechanisms remain uncertain.To bridge this gap,a three-year field experiment was conducted with five fertilization regimes:i)Control,non-fertilization;CF,conventional synthetic fertilizer application;CF_(1/2)M_(1/2),1/2 N input via synthetic fertilizer and 1/2 N input via manure;CF_(1/4)M_(3/4),1/4 N input synthetic fertilizer and 3/4 N input via manure;M,manure application.All fertilization treatments were designed to have equal N input.Our results showed that all manure substituted treatments achieved high soil fertility indexes(SFI)and productivities by increasing the soil organic carbon(SOC),total N(TN)and available phosphorus(AP)concentrations,and by altering the bacterial community diversity and composition compared with CF.SOC,AP,and the soil C:N ratio were mainly responsible for microbial community variations.The co-occurrence network revealed that SOC and AP had strong positive associations with Rhodospirillales and Burkholderiales,while TN and C:N ratio had positive and negative associations with Micromonosporaceae,respectively.These specific taxa are implicated in soil macroelement turnover.Random Forest analysis predicted that both biotic(bacterial composition and Micromonosporaceae)and abiotic(AP,SOC,SFI,and TN)factors had significant effects on crop yield.The present work strengthens our understanding of the effects of manure substitution on crop yield and provides theoretical support for optimizing fertilization strategies. 展开更多
关键词 FERTILIZATION manure substitution soil fertility maize yield bacterial community
下载PDF
Nitrogen mineralization in the oldest climax communities in the eastern Mediterranean region
15
作者 Fatma Selcen Sakar Gürcan Güleryüz 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期213-228,共16页
In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest communities.In the oldest ... In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest communities.In the oldest pure communi-ties of Pinus nigra(PN),Fagus orientalis(FO),and Abies bornmuelleriana(AB)in the mountain range of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 year.Sampling locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding capacity(%),organic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest communities.F.orientalis had the highest annual net Nmin yield(43.9±4.8 kg ha^(-1) a^(-1)),P.nigra the lowest(30.5±4.2 kg ha^(-1) a^(-1)).Our findings show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling and that hydrolyzed tannic acids and total phenolic compounds effectively control N turnover.Tannic acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification. 展开更多
关键词 Oldest forest communities Nitrogen mineralization NITRIFICATION Tannic acid Total phenolic LITTER
下载PDF
Spatial Optimization and Reconstruction of Old Communities under the Background of Aging
16
作者 LI Yiwen LI Daoyong HE Qilin 《Journal of Landscape Research》 2024年第2期51-53,60,共4页
As aging becomes increasingly serious,how to make the life of the elderly more convenient and comfortable has become one of the social problems to be solved urgently.Old residential areas are one of spaces where the e... As aging becomes increasingly serious,how to make the life of the elderly more convenient and comfortable has become one of the social problems to be solved urgently.Old residential areas are one of spaces where the elderly gather.In this paper,the prominent problems in the community space of existing old residential areas that are not conducive to the life of the elderly were analyzed,and corresponding countermeasures to transform the community space were put forward.It is hoped that public space can play its due value and make old residential areas glow with new vitality. 展开更多
关键词 Aging adaptability community public space Elderly care community Space transformation
下载PDF
Effects of potassium lactate on sensory attributes,bacterial community succession and biogenic amines formation in Rugao ham
17
作者 Renyong Liao Ying Wang +4 位作者 Qiang Xia Changyu Zhou Fang Geng Daodong Pan Jinxuan Cao 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期198-210,共13页
To deepen the understanding in the effect of potassium lactate on the sensory quality and safety of Rugao ham,sensory attributes,physicochemical parameters,total volatile basic nitrogen(TVBN),microorganism community a... To deepen the understanding in the effect of potassium lactate on the sensory quality and safety of Rugao ham,sensory attributes,physicochemical parameters,total volatile basic nitrogen(TVBN),microorganism community and biogenic amines of Rugao ham manufactured with different potassium lactate levels(0%,0.5%,1%,2%)were investigated;the relationship between microbial community and the formation of TVBN and biogenic amines was further evaluated.With the increase of potassium lactate from 0%to 2%,the increased sensory scores and the decreased total aerobic bacterial count and TVBN were observed;the abundance of Staphylococcus increased,while the content of Halomonas decreased.LDA effect size(LEf Se)and correlations analysis showed that Staphylococcus equorum and Lactobacillus fermentum could be the key species to improve sensory scores and decrease biogenic amines and TVBN.Metabolic pathway analysis further showed that amino acids metabolism and nitrogen metabolism were mainly involved in decreasing TVBN and biogenic amines in the treatment of 2%potassium lactate. 展开更多
关键词 Rugao ham Potassium lactate Biogenic amines Microbial community Metabolic pathways
下载PDF
Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020
18
作者 Shi-Guang Wei Lin Li +3 位作者 Kun-Dong Bai Zhi-Feng Wen Jing-Gang Zhou Qin Lin 《Plant Diversity》 SCIE CAS CSCD 2024年第1期70-77,共8页
Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest chang... Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest changed over a 15-year period.Specifically,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya concinna.The numbers of individual deaths for common species were concentrated in the small and mid-diameter level.The spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats increased.In 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey years.Extreme weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved forests.Our findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure. 展开更多
关键词 community structure Death and renewal dynamics Species diversity dynamics South subtropical forest
下载PDF
The Burden of Undiagnosed Hypertension and Associated Risk Factors among Adults in a Rural Community in Imo Sate, South-East Nigeria
19
作者 Iwunze Anuli Egwim Jideuma +4 位作者 Onuoha Frank Olekanma Chinonye Ndukwu Chiagozie Igbonagwam Hope Dike Victor 《International Journal of Clinical Medicine》 CAS 2024年第2期101-122,共22页
Background: Cardiovascular diseases are the leading cause of death globally and hypertension is a major contributor to this burden. Many people with hypertension have poorly controlled blood pressure and up to half of... Background: Cardiovascular diseases are the leading cause of death globally and hypertension is a major contributor to this burden. Many people with hypertension have poorly controlled blood pressure and up to half of the adults with hypertension are unaware of their hypertensive status due to factors that bother on poor management and poor screening approaches. The implication is that people who have poor access to healthcare especially those in the rural communities are at increased risk of cardiovascular complications and all-cause mortality. Unfortunately, not much has been done to ascertain the burden of undiagnosed hypertension and associated risk factors in rural communities in Nigeria. Methods: We conducted a community-based cross-sectional study in a rural community in Imo State, Nigeria, on burden of undiagnosed hypertension with participants recruited via a multi-stage sampling method. An interviewer-administered questionnaire was used, and standardized instruments were applied to obtain, process and analyze the data. Tests of association between the independent variables and outcome were conducted using logistic regression. P-value of Results: A total of 380 adults participated in the study. The mean age was 44.2 years. The prevalence of undiagnosed hypertension was 35.8%. Logistic regression revealed that age, with the respondents in the age groups 26 - 35 years (OR = 10.647, 1.910 - 59.345, p-value = 0.007), 36 - 45 (OR = 3.680, 1.263 - 10.723, p-value = 0.017), 46 - 55 years (OR = 2.737, 1.114 - 6.727, p-value = 0.039), 56 - 65 years old (OR = 3.384, 1.610 - 7.115, p-value = 0.001);and being married (OR = 3.846, 1.118 - 13.233, p-value = 0.033), were independent risk factors for undiagnosed hypertension. Conclusion: The prevalence of undiagnosed hypertension in the rural population of South-East Nigeria is high. Younger age (26 - 35 years) had the highest odds of risk for occurrence of hypertension. Also being married was identified as a risk factor for undiagnosed hypertension. 展开更多
关键词 HYPERTENSION Undiagnosed Hypertension Risk Factors Rural community
下载PDF
Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem
20
作者 HAO Aihua LUO Zhengming CHEN Xiaojiang 《Journal of Mountain Science》 SCIE CSCD 2024年第1期146-159,共14页
Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradient... Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern China. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(P<0.05), and the percentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOC, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil C: N, p H, NO_(3)^(-)-N, or NH_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(P<0.01) and Shannon-Weiner index(P<0.05) at low elevational gradients but significantly decreased belowground biomass(P<0.05) at a depth of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(P<0.05), but significant nonlinear responses to soil temperature and soil moisture in the warmed treatment(P<0.05). The warmed aboveground biomass had a significant nonlinear response to soil temperature and significant linear responses to soil moisture(P<0.05). This study provided evidence that altitude is a factor in sensitivity to climate warming, and these different parameters(e.g., plant species richness, Shannon-Weiner index, soil temperature, soil moisture, SOC, and TN) can be used to measure this sensitivity. 展开更多
关键词 Warming effect Plant diversity pattern community structure change Elevation gradient Alpine meadow ecosystem Mount Wutai
下载PDF
上一页 1 2 223 下一页 到第
使用帮助 返回顶部