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Sustainability Assessment of Banana (Musa spp.) Yield Gap Reduction through Value Chain Development Interventions in Smallholder Farming Systems in Manicaland, Zimbabwe
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作者 Mthintwa Tawanda Hove Hlamalani Ngwenya Johan Van Niekerk 《Agricultural Sciences》 2024年第8期962-992,共31页
This study evaluated the effectiveness of donor supported agricultural value chain development projects in sustainably narrowing yield gaps for banana smallholder farmer producers in Manicaland, Zimbabwe. The study us... This study evaluated the effectiveness of donor supported agricultural value chain development projects in sustainably narrowing yield gaps for banana smallholder farmer producers in Manicaland, Zimbabwe. The study used a mixed methods research design that relied on farmers records for the quantitative analysis and focus group discussion and in-depth interviews for key experts for the qualitative aspects. A mix of regression analysis, t-tests, Pearsons’s correlation and analysis of variance statistical methods were used for the quantitative analysis while thematic response analysis was used for the qualitative engagements. The findings showed that by the end of the activity, the project had successfully narrowed the banana yield gaps to 18.66 tons per hectare working with a potential yield base of 40 tons. However, 5 years after the project closure the yield gap had fallen to 24.7 tons indicating a lack of sustainability of yield gap reduction. However, the yield gap slump does not override the fact that farmers on average were still able to sell approximately 5 tons per every 6 months after 5 years from the project closure which is beyond any poverty threshold. This suggests genuine upward economic mobility. Additionally, in analyzing what factors had the greatest influence on yield gap reduction, the access to fertilizer ranked highest where genetics, irrigation and improved agronomy followed in that respective order. The study further showed that farmers who receive value chain development support whilst at an already commercialized state tend to maintain productivity thresholds higher in comparison to those who are at a pre commercial state. This is evidenced by the fact that the pre commercial farmers had a yield reduction of 30.83 percent after 5 years of the project closure whereas the former realized a productivity growth of 7.84%. In conclusion, whilst the intervention was successful in transitioning farmers out of poverty, more investment should be made towards transitioning smallholder farmers to integrated soil fertility management practices and improvement of agronomic efficiency through stronger on field collaboration between research institutions, the government and development institutions. 展开更多
关键词 Yield Gap Value Chain development Soil Health Varietal Replacement Rate Sustainability and Economic Mobility
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New aspects of a small GTPase RAB35 in brain development and function
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作者 Ikuko Maejima Ken Sato 《Neural Regeneration Research》 SCIE CAS 2025年第7期1971-1980,共10页
In eukaryotic cells,organelles in the secretory,lysosomal,and endocytic pathways actively exchange biological materials with each other through intracellular membrane trafficking,which is the process of transporting t... In eukaryotic cells,organelles in the secretory,lysosomal,and endocytic pathways actively exchange biological materials with each other through intracellular membrane trafficking,which is the process of transporting the cargo of proteins,lipids,and other molecules to appropriate compartments via transport vesicles or intermediates.These processes are strictly regulated by various small GTPases such as the RAS-like in rat brain(RAB)protein family,which is the largest subfamily of the RAS superfamily.Dysfunction of membrane trafficking affects tissue homeostasis and leads to a wide range of diseases,including neurological disorders and neurodegenerative diseases.Therefore,it is important to understand the physiological and pathological roles of RAB proteins in brain function.RAB35,a member of the RAB family,is an evolutionarily conserved protein in metazoans.A wide range of studies using cultured mammalian cells and model organisms have revealed that RAB35 mediates various processes such as cytokinesis,endocytic recycling,actin bundling,and cell migration.RAB35 is also involved in neurite outgrowth and turnover of synaptic vesicles.We generated brain-specific Rab35 knockout mice to study the physiological roles of RAB35 in brain development and function.These mice exhibited defects in anxiety-related behaviors and spatial memory.Strikingly,RAB35 is required for the precise positioning of pyramidal neurons during hippocampal development,and thereby for normal hippocampal lamination.In contrast,layer formation in the cerebral cortex occurred superficially,even in the absence of RAB35,suggesting a predominant role for RAB35 in hippocampal development rather than in cerebral cortex development.Recent studies have suggested an association between RAB35 and neurodegenerative diseases,including Parkinson's disease and Alzheimer's disease.In this review,we provide an overview of the current understanding of subcellular functions of RAB35.We also provide insights into the physiological role of RAB35 in mammalian brain development and function,and discuss the involvement of RAB35 dysfunction in neurodegenerative diseases. 展开更多
关键词 ENDOCYTOSIS ENDOSOMES hippocampal development neurodegenerative diseases RAB35
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From Knowledge Transfer to Capability Development:The Future of PBL+CBL Teaching Method in Operating Room Nursing Education
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作者 Kun Zhu Jiao Zhou +3 位作者 Yaqing Cui Zhengyan Shi Juntao Li Jia Li 《Journal of Contemporary Educational Research》 2024年第10期185-191,共7页
Concomitant with the advancement of contemporary medical technology,the significance of perioperative nursing has been increasingly accentuated,necessitating elevated standards for the pedagogy of perioperative nursin... Concomitant with the advancement of contemporary medical technology,the significance of perioperative nursing has been increasingly accentuated,necessitating elevated standards for the pedagogy of perioperative nursing.Presently,the PBL(problem-based learning)pedagogical approach,when integrated with CBL(case-based learning),has garnered considerable interest.An extensive literature review has been conducted to analyze the application of the PBL-CBL fusion in the education of perioperative nursing.Findings indicate that this integrative teaching methodology not only enhances students’theoretical knowledge,practical competencies,and collaborative skills but also contributes to the elevation of teaching quality.In conclusion,the PBL-CBL teaching approach holds immense potential for broader application in perioperative nursing education.Nevertheless,it is imperative to continually refine this combined pedagogical strategy to further enhance the caliber of perioperative nursing instruction and to cultivate a greater number of exceptional nursing professionals in the operating room setting. 展开更多
关键词 Knowledge transfer Capability development PBL+CBL teaching method Operating room nursing EDUCATION
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Establishment of human cerebral organoid systems to model early neural development and assess the central neurotoxicity of environmental toxins
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作者 Daiyu Hu Yuanqing Cao +6 位作者 Chenglin Cai Guangming Wang Min Zhou Luying Peng Yantao Fan Qiong Lai Zhengliang Gao 《Neural Regeneration Research》 SCIE CAS 2025年第1期242-252,共11页
Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-li... Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and disease.To enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid culture.This involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid system.This cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology testing.As a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental toxins.Brain organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature differentiation.Cadmium exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic locations.The convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies. 展开更多
关键词 cadmium cell death cell proliferation cortical development environmental toxins neural progenitor cells NEUROGENESIS NEUROTOXICOLOGY ORGANOIDS stem cells
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An Exploration of Higher Vocational English Teachers’Professional Development on Students’Learning Ability in the Context of New Liberal Arts
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作者 Jing Xu Mohd Nazir Bin Zabit 《Journal of Contemporary Educational Research》 2024年第2期203-207,共5页
The concept of New Liberal Arts,a multidisciplinary combined integrator with Chinese values at its core,has brought new challenges to the teaching methods and professional development of higher-level English teachers.... The concept of New Liberal Arts,a multidisciplinary combined integrator with Chinese values at its core,has brought new challenges to the teaching methods and professional development of higher-level English teachers.Based on the evolving professional development process of higher vocational English teachers in the context of the New Liberal Arts,this article analyzes how English teachers can integrate multidisciplinary knowledge and adopt advanced educational technology in the teaching process.On this basis,it discusses the role of teachers’professional development in enhancing students’learning ability,such as through deepening disciplinary understanding,adopting innovative teaching strategies,and implementing personalized teaching.At the end of the article,based on a variety of pedagogical theories,we put forward suggestions,including continuous professional training,interdisciplinary cooperation,and the application of innovative teaching techniques,which are mainly aimed at helping higher vocational English teachers get rid of the dilemma of the new situation,adapt to the needs of the new liberal arts education as soon as possible,and then effectively improve students’abilities. 展开更多
关键词 New liberal arts Higher vocational education Professional development of English teachers Interdisciplinary teaching Personalized teaching
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Postnatal development of rat retina:a continuous observation and comparison between the organotypic retinal explant model and in vivo development
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作者 Baoqi Hu Rui Wang +8 位作者 Hanyue Zhang Xiou Wang Sijia Zhou Bo Ma Yan Luan Xin Wang Xinlin Chen Zhichao Zhang Qianyan Kang 《Neural Regeneration Research》 SCIE CAS 2025年第3期900-912,共13页
The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and contin... The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development studies.Thus,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo retina.In this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in vivo.Initially,we used SOX2 and PAX6 immunostaining to identify retinal progenitor cells.We then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,respectively.Ki-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between groups.Additionally,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,respectively.The timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant retinas.Our study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina development.The findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation. 展开更多
关键词 bipolar cells differentiation in vivo microglia Müller glia organotypic retinal explant culture postnatal retina development proliferation retinal progenitor cells
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GIS-based Ecological Suitability Assessment for Land Use——A Case Study of an Economic Development Zone in Shenyang
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作者 高会艳 王东明 《Agricultural Science & Technology》 CAS 2013年第9期1332-1334,共3页
Analysis indices of ecological suitability were selected through literature reviewing and expert consultation. Visualization of assessment course was achieved based on different land use functions with the help of Arc... Analysis indices of ecological suitability were selected through literature reviewing and expert consultation. Visualization of assessment course was achieved based on different land use functions with the help of ArcGIS9.0 and GIS layers with different properties were overlapped and computed with GIS grids. Hence, the areas were colored and reclassified(colors representing different ecological suitability degrees). Finally, land use functions can be readjusted by the evaluation results,providing references for rational planning of economic development zones. 展开更多
关键词 Ecological suitability assessment Economic development zone Environmental assessment
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Simulating the Effect of Hydrate Dissociation on Wellhead Stability During Oil and Gas Development in Deepwater 被引量:13
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作者 LI Qingchao CHENG Yuanfang +2 位作者 ZHANG Huaiwen YAN Chuanliang LIU Yuwen 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第1期35-45,共11页
It is well known that methane hydrate has been identified as an alternative resource due to its massive reserves and clean property. However, hydrate dissociation during oil and gas development(OGD) process in deep wa... It is well known that methane hydrate has been identified as an alternative resource due to its massive reserves and clean property. However, hydrate dissociation during oil and gas development(OGD) process in deep water can affect the stability of subsea equipment and formation. Currently, there is a serious lack of studies over quantitative assessment on the effects of hydrate dissociation on wellhead stability. In order to solve this problem, ABAQUS finite element software was used to develop a model and to evaluate the behavior of wellhead caused by hydrate dissociation. The factors that affect the wellhead stability include dissociation range, depth of hydrate formation and mechanical properties of dissociated hydrate region. Based on these, series of simulations were carried out to determine the wellhead displacement. The results revealed that, continuous dissociation of hydrate in homogeneous and isotropic formations can causes the non-linear increment in vertical displacement of wellhead. The displacement of wellhead showed good agreement with the settlement of overlying formations under the same conditions. In addition, the shallower and thicker hydrate formation can aggravate the influence of hydrate dissociation on the wellhead stability. Further, it was observed that with the declining elastic modulus and Poisson's ratio, the wellhead displacement increases. Hence, these findings not only confirm the effect of hydrate dissociation on the wellhead stability, but also lend support to the actions, such as cooling the drilling fluid, which can reduce the hydrate dissociation range and further make deepwater operations safer and more efficient. 展开更多
关键词 DISSOCIATION of HYDRATE oil and gas development in DEEPWATER WELLHEAD STability finite element simulation
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Development of Chinese Near-isogenic Line of Rice and Their Differentiating Ability of Pathogenic Races of Blast Fungus 被引量:11
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作者 LING Zhong-zhuan T. Mew WANG Jiu-lin LEI Cai-ling HUANG Ning 《Agricultural Sciences in China》 CAS CSCD 2001年第1期50-56,共7页
The rice( Oryza L. ) variety, Lijiangxintuanheigu(LTH), is a universally susceptible variety. A set of near-isogenic lines (NILs) of rice which has single resistance gene for each line was developed by use of LTH as r... The rice( Oryza L. ) variety, Lijiangxintuanheigu(LTH), is a universally susceptible variety. A set of near-isogenic lines (NILs) of rice which has single resistance gene for each line was developed by use of LTH as recurrent parent and Kusabue,Tsuyuake, K1, PiNo. 4, K60 and BL1, which are from Kiyosawa's differential varieties(KDV), as donor parents. Differentiating ability of these NILs to Philippine isolates was compared with that of their donor parents, KDV and IRRI' s NILs. The results of comparative studies were as follows: (1) Differentiating ability of Chinese NILs to Philippine isolates was much stronger than that of their donor parents and that of KDV. (2) Chinese NILs had similar ability to differentiate races to IRRI's NILs or higher differentiating ability than them. But IRRI's NILs almost had no differentiating ability to isolates from japonica rice-growing regions. They can not be used to differentiate races of isolates from japonica ricegrowing regions. Whereas, Chinese NILs can be used to differentiate races of isolates from both japonica ricegrowing regions and indica rice-growing regions. It was concluded that the set of Chinese NILs can be used as international differentials. 展开更多
关键词 Near-isogenic LINES PYRICULARIA grisa PATHOGENIC RACES DIFFERENTIATING ability
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Vulnerability and Sustainable Development Mode of Coal Cities in Northeast China 被引量:9
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作者 LI Bo TONG Lianjun 《Chinese Geographical Science》 SCIE CSCD 2008年第2期119-126,共8页
In this study, by carrying on the spot investigation to the seven coal cities in Northeast China and interview-ing with the local authority and the residents, the authors definite the vulnerability that is closed to e... In this study, by carrying on the spot investigation to the seven coal cities in Northeast China and interview-ing with the local authority and the residents, the authors definite the vulnerability that is closed to exposure, sensitiv-ity and resilience, and set up vulnerability model of coal cities in Northeast China. At the same time, the authors broadly illustrate how the components of natural-social-economic system act in the coal area, so as to probe the ways to reduce vulnerability more effectively, such as preferential national policy and so on. Furthermore, the article studies the relationship between vulnerability and sustainable development. Vulnerability is a spatio-temporal function of sus-tainable development. The regional sustainable development refrains the spiral ascending of vulnerability. And the re-gional vulnerability and sustainable development appear in turn. Then the article analyzes the natural vulnerability, so-cial vulnerability and economic vulnerability of coal cities in Northeast China. At last, combing vulnerability model and situation of coal cities in Northeast China, the authors put forward regional technology innovation mode, multi-dimension structure transformation mode, attracting investment mode and recycling economy mode to reduce vulnerability. 展开更多
关键词 VULNERability coal city sustainable development Northeast China
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Applicability and Prospect of China's Development Zone Model in Africa 被引量:5
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作者 WANG Xingping ZHU Kai +1 位作者 LI Yingcheng XU Jiabo 《Chinese Geographical Science》 SCIE CSCD 2017年第6期860-874,共15页
Development zones have been an important spatial approach to opening-up. They have also been major contributors to the processes of promoting economic development since China's reform and China's industrialization a... Development zones have been an important spatial approach to opening-up. They have also been major contributors to the processes of promoting economic development since China's reform and China's industrialization and urbanization. Along with im- provements in the worldwide industrial division of labor and the gradual implementation of China's development zones' Go Global strategy, it is necessary for Africa, a hot spot of global industrialization in recent years, to learn from China's development zone model. By attracting China's capital, technology and enterprises to Africa via Sino-African co-built development zones, a pattern of high com- plementarity and mutual development between China and Africa can be formed which does favor further improvement of the global industrial division of labor. In order to study the applicability and prospect of China's development zone model in Africa as per the above-mentioned international situation, this paper first sorts out the development course of China's development zones and discusses their roles in China's industrialization and urbanization. Subsequently, this paper analyzes the status quo of industrial development in Africa as a whole and the differences in industrial development between China and Africa, aiming to justify the timing of industrial transfer from China to Africa by constructing Sino-African co-built development zones. Lastly, this paper analyzes the current situation of six Sino-African co-built development zones by focusing on their operation modes, industry types and investment promotion models. In the authors' view, Sino-African co-built development zones can function as a new window of China-African cooperation, a new car- rier of African industrialization, and a new engine of global industrial restructuring. China should adhere to the general principles of 'Sino-African Integration, Multi-Cooperation, Mutual Benefit, Scientific Location, Systematic Planning, Cluster Growth and Open De- velopment' in the planning and construction of development zones in Africa, effectively promoting Africa as the very important part of the global industry system. 展开更多
关键词 development zones China AFRICA INDUSTRIALIZATION
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Inhibitory Ability of Children with Developmental Dyscalculia 被引量:1
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作者 张怀英 吴汉荣 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2011年第1期131-136,共6页
Inhibitory ability of children with developmental dyscalculia(DD) was investigated to explore the cognitive mechanism underlying DD.According to the definition of developmental dyscalculia,19 children with DD-only a... Inhibitory ability of children with developmental dyscalculia(DD) was investigated to explore the cognitive mechanism underlying DD.According to the definition of developmental dyscalculia,19 children with DD-only and 10 children with DD&RD(DD combined with reading disability) were selected step by step,children in two control groups were matched with children in case groups by gender and age,and the match ratio was 1:1.Psychological testing software named DMDX was used to measure inhibitory ability of the subjects.The differences of reaction time in number Stroop tasks and differences of accuracy in incongruent condition of color-word Stroop tasks and object inhibition tasks between DD-only children and their controls reached significant levels(P〈0.05),and the differences of reaction time in number Stroop tasks between dyscalculic and normal children did not disappear after controlling the non-executive components.The difference of accuracy in color-word incongruent tasks between children with DD&RD and normal children reached significant levels(P〈0.05).Children with DD-only confronted with general inhibitory deficits,while children with DD&RD confronted with word inhibitory deficits only. 展开更多
关键词 developmental dyscalculia CHILDREN DMDX software inhibitory ability
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Research from global Sustainable Development Goals(SDGs)to sustainability science based on the object-subject-process framework 被引量:9
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作者 Dajian Zhu 《Chinese Journal of Population,Resources and Environment》 2017年第1期8-20,共13页
Since United Nations adopted the global Sustainable Development Goals(SDGs) for the next15 years(2016-2030), sustainable development will further become a core concept and main principle to guide global and national e... Since United Nations adopted the global Sustainable Development Goals(SDGs) for the next15 years(2016-2030), sustainable development will further become a core concept and main principle to guide global and national economic and social development. According to this background, strengthening the integrative research on the theories and methodologies of sustainable development has been a strategically important mission. This article provided an analytic framework for sustainability science, named the object-subject-process(OSP) framework for examining the key issues encountered during the theoretical research and policy analysis. This study emphasized that, on the object dimension, sustainable development means to seek for economic and social development within biophysical limits of the earth and the relationship of environment, society, and economy should be containing and complementary rather than parallel and substitute; on the process dimension, sustainable development should adopt both the responsive and proactive strategies for the whole process management which employing pressure-state-response(PRS) model rather than dealing with one part of them; on the subject dimension, sustainable development research should involve the key stakeholders who are kind of collaborate governance rather than separate each other. From the perspective of sustainability science, green economy was utilized as a case study to explore the issues of object, process and subject and also the significance of green economy was discussed in this study. 展开更多
关键词 Sustainable development sustainability science object-process-subjectanalysis green economy
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Green Tourism in Mountain Regions-Reducing Vulnerability and Promoting People and Place Centric Development in the Himalayas 被引量:8
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作者 R. B. Singh D. K. Mishra 《Journal of Mountain Science》 SCIE CSCD 2004年第1期57-64,共8页
In recent years, mountain regions are attracting great attention to Indian tourists in general and foreign tourists in particular. The potential mountain resources for promoting green tourism are enormous in the form ... In recent years, mountain regions are attracting great attention to Indian tourists in general and foreign tourists in particular. The potential mountain resources for promoting green tourism are enormous in the form of natural and cultural heritage such as biosphere reserves, flora and fauna, lakes and rivers and traditional rural resources. In order to utilise tourism industry market, uncontrolled numbers of tourists and related haphazard infrastructural facilities in the vulnerable mountain regions pose serious environmental implications. The ecological pressures are threatening land, water and wild life resources through direct and indirect environmental impacts together with generation of solid and liquid wastes, so green tourism is emerging as an important task in order to develop new relationship between communities, government agencies and private sectors. The strategy focuses on ecological understanding, environmental protection and ecodevelopment. The major attributes of the green tourism include environmental conservation and education and distribution of income to local people based on strong partnership. Various knowledge systems go a long way for achieving the goals of the green tourism, which creates awareness about the value of environmental resources. Mountains have ecological, recreational, educational and scientific values, which need to be utilised in sustainable way. Various tourist activities and facilities need to be diversified in order to achieve multiple benefits including scientific field excursion, recreation in natural and cultural areas, community festivals and sport tourisms. Green tourism considers tourism development as an integral part of a national and regional development. The paper discusses the social, economic and environmental dimensions of the green tourism with particular reference to village tourism development programme taking empirical evidences from the Himalaya. Such programme also minimises biophysical and human vulnerability and risks in mountain regions. The environmental consciousness campaign and introduction of code through multi- purpose Tourist Resource Centres are gaining currency in above context. 展开更多
关键词 Mountain region green tourism development programme Kullu Himalaya
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Designing a Comprehensive Skill Evaluation and Vocational Ability Development Program for FTTH Installer 被引量:1
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作者 Takuo Kikuchi 《Computer Technology and Application》 2015年第1期5-13,共9页
Recently, FTTH (fiber to the home) is spreading rapidly, and communication technology has become an indispensable part in our lives. FTTH installers who build the infi'astructure must correspond to the progress of ... Recently, FTTH (fiber to the home) is spreading rapidly, and communication technology has become an indispensable part in our lives. FTTH installers who build the infi'astructure must correspond to the progress of technology while ensuring a high quality of installation, and it is struggling to its counterpart. The present study is undertaken in order to propose effective vocational ability development program for FTTH installers from the approach of their skill. They are information network cabling-related qualification system and competitions as the ability evaluation system. Then the author concludes that this program makes a contribution to improving their skill and maintaining the quality of the optical fiber network in analyzing some example of actual installation work and the measurement result of the OTDR(optical time domain reflect) meter. 展开更多
关键词 Vocational ability development program FTTH installer installation skill evaluation system.
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Vulnerability assessment of the Satluj catchment for sustainable development of hydroelectric projects in the northwestern Himalaya 被引量:1
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作者 Jagdish Chandra KUNIYAL Amit JAMWAL +3 位作者 Nidhi KANWAR Bhim CHAND Kireet KUMAR Pitamber Prasad DHYANI 《Journal of Mountain Science》 SCIE CSCD 2019年第12期2714-2738,共25页
Hydropower if scientifically developed is considered to be one of the clean and non-polluted renewable energy sources.But its impacts always exist on physical and social environment of the area.The present study was c... Hydropower if scientifically developed is considered to be one of the clean and non-polluted renewable energy sources.But its impacts always exist on physical and social environment of the area.The present study was conducted in the River Satluj basin which is well known for its hydropower potential.The main objective of the study was to understand the vulnerability of the Satluj basin and to develop a strategy for the development of hydropower projects.This basin has been facing many problems relating to construction of haphazard development of hydropower projects.This has led multi-hazards like landslides,floods,earthquakes,etc.Here,vulnerability assessment index was assessed quantitatively and qualitatively.Geographical Information System and people’s perception were used to study these aspects in the basin.The parameters considered for vulnerability assessment were slope,slope profile,relative relief,curvature,slope aspect,soil texture,lithology,river morphometry,precipitation,hydroelectric projects,land use and land cover,mass-movement,flood,geological elements and earthquake occurrences.The highest vulnerability was found in the middle zone,and finally on the basis of parameters analyzed;the hydropower’s development strategy was developed. 展开更多
关键词 Hazards Vulnerability assessment Hydroelectric projects Sustainable development Satluj basin
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Development of 30Cr06A,a high strength cast steel and its welding ability 被引量:3
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作者 GAO You-jin 《Journal of China University of Mining and Technology》 EI 2008年第2期296-299,共4页
High performance hydraulic supports have a high requirement in strength,toughness and welding ability of socket mate- rial.Targeting this problem,we analyzed the properties of the high strength socket material 30Cr06,... High performance hydraulic supports have a high requirement in strength,toughness and welding ability of socket mate- rial.Targeting this problem,we analyzed the properties of the high strength socket material 30Cr06,used in high performance hy- draulic supports both at home and abroad and developed a new kind of high strength cast steel 30Cr06A,by making use of an or- thogonal experiment,which provided the design conditions for its optimal composition.The result shows that the strength and toughness of the newly developed high strength cast steel 30Cr06A is much better than that of 30Cr06.Theoretical calculations,mechanical property tests and hardness distribution tests of welded joints were carried out for a study of the welding ability of the new material,which is proved to be very good.Therefore,this 30Cr06A material has been successfully used in the socket of high performance hydraulic support. 展开更多
关键词 Hydraulic support socket material 30Cr06A strength TOUGHNESS welding ability
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Trend and Interannual Variability of Chinese Air Pollution since 2000 in Association with Socioeconomic Development: A Brief Overview 被引量:7
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作者 LIN Jin-Tai PAN Da ZHANG Rui-Xiong 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第2期84-89,共6页
Abstract Chinese air pollution has increased in this century along with the rapid socioeconomic development and resulting anthropogenic emissions. While recent emission control measures have shown encouraging re sults... Abstract Chinese air pollution has increased in this century along with the rapid socioeconomic development and resulting anthropogenic emissions. While recent emission control measures have shown encouraging re sults and have reduced the levels of sulfur dioxide and primary aerosols, the concentrations of other air pollutants continue to grow, particularly secondary pollutants in cluding ozone and secondary aerosols. Meanwhile, a va riety of intentional and unintentional socioeconomic events have temporarily changed the pace, and even the signs, of growth of air pollution. These events include the short-term emission restrictions imposed during the Sino-African Summit, the Beijing Olympics and Para lympics, the Shanghai World Exposition (Shanghai Expo), the Guangzhou Asian Olympics, and the Shenzhen Uni versiade, as well as the unintentional emission reductions associated with the recent economic recession and the annual Chinese New Year. This paper presents a brief overview of trends and temporary perturbations of Chi nese air pollution since 2000, summarizing studies on anthropogenic emission inventories, atmospheric meas urements, and inverse modeling. It concludes with rec ommendations for future research. 展开更多
关键词 air pollution trend and variability socioeconomic development satellite measurements bottom-upemission inventories top-down constraints
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Thermal stability and microstructure development of cast and powder metallurgy produced Mg-Y-Zn alloy during heat treatment 被引量:3
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作者 Tomas Kekule Bohumil Smola +3 位作者 Martin Vlach Hana Kudrnova Veronika Kodetova Ivana Stulikova 《Journal of Magnesium and Alloys》 SCIE EI CAS 2017年第2期173-180,共8页
Response to isochronal annealing up to 440 ℃ of squeeze cast Mg–Y–Zn alloy and of the same alloy prepared by powder metallurgy(PM)and extruded at 280 ℃ was studied by resistivity and microhardness measurement,diff... Response to isochronal annealing up to 440 ℃ of squeeze cast Mg–Y–Zn alloy and of the same alloy prepared by powder metallurgy(PM)and extruded at 280 ℃ was studied by resistivity and microhardness measurement,differential scanning calorimetry(DSC)and microstructure investigation.Electrical resistivity was measured at 77 K and microhardness was measured at room temperature after each annealing step.DSC measurement was performed at various heating rates.Transmission and scanning electron microscopy and optical microscopy revealed ribbons of long-period ordered structure(LPSO)18R and planar defects within grain boundaries.Relatively high density of planar defects was found in grain interiors of the cast alloy with the grain size approximately 50μm.Well pronounced subgrains were observed in the PM prepared alloy.Secondary phase particles decorate grain boundaries in this alloy.Three precipitation processes were detected in the cast alloy during repeated isochronal annealing up to 440 ℃,whereas only one significant process was revealed in the PM alloy.These processes were identified as embedding of stacking faults by solutes,development and rearrangement(18R→14H)of LPSO phase and development of grain boundary particles.A coarsening of grain boundary particles rich in Y and Zn only proceeds in the PM alloy.Activation energies of the precipitation processes were determined.Microhardness exhibits good thermal stability against annealing up to 360 ℃ in the PM alloy. 展开更多
关键词 Mg-Y-Zn alloys Powder metallurgy MICROHARDNESS Microstructure development Electrical resistivity
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Development of the theory and technology for low permeability reservoirs in China 被引量:7
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作者 HU Wenrui WEI Yi BAO Jingwei 《Petroleum Exploration and Development》 2018年第4期685-697,共13页
The development theories of low-permeability oil and gas reservoirs are refined, the key development technologies are summarized, and the prospect and technical direction of sustainable development are discussed based... The development theories of low-permeability oil and gas reservoirs are refined, the key development technologies are summarized, and the prospect and technical direction of sustainable development are discussed based on the understanding and research on developed low-permeability oil and gas resources in China. The main achievements include:(1) the theories of low-permeability reservoir seepage, dual-medium seepage, relative homogeneity, etc.(2) the well location optimization technology combining favorable area of reservoir with gas-bearing prediction and combining pre-stack with post-stack;(3) oriented perforating multi-fracture, multistage sand adding, multistage temporary plugging, vertical well multilayer, horizontal and other fracturing techniques to improve productivity of single well;(4) the technology of increasing injection and keeping pressure, such as overall decreasing pressure, local pressurization, shaped charge stamping and plugging removal, fine separate injection, mild advanced water injection and so on;(5) enhanced recovery technology of optimization of injection-production well network in horizontal wells. To continue to develop low-permeability reserves economically and effectively, there are three aspects of work to be done well:(1) depending on technical improvement, continue to innovate new technologies and methods, establish a new mode of low quality reservoir development economically, determine the main technical boundaries and form replacement technology reserves of advanced development;(2) adhering to the management system of low cost technology & low cost, set up a complete set of low-cost dual integration innovation system through continuous innovation in technology and management;(3) striving for national preferential policies. 展开更多
关键词 low permeability oil and gas reservoir SEEPAGE THEORY volume FRACTURING WATERFLOODING technology WELL location optimization horizontal WELL technical development direction
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