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Nutrition impacts of non-solid cooking fuel adoption on under-five children in developing countries 被引量:1
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作者 Yalin Tang Yuhe Guo +1 位作者 Gang Xie Chengfang Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期397-413,共17页
This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demogra... This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demographic and Health Surveys(DHS).Results from both fixed effects(FE)and instrumental variable(IV)estimates show that using non-solid cooking fuel significantly improves the nutrition outcomes of under-five children.Compared with their peers from households mainly using solid fuel,children from households mainly using non-solid fuel exhibit a lower probability of experiencing stunting(by 5.9 percentage points)and being underweight(by 1.2 percentage points).Our further investigation provides evidence for several underlying mechanisms,such as improved indoor air quality,induced reduction in children’s respiratory symptoms,benefits on maternal health,and reduction in maternal time spent on fuel collection or cooking.Heterogenous analyses suggest that the nutrition benefits of using non-solid cooking fuel are more prominent among boys,children above three years old,and those from households of lower socioeconomic status,rural areas,and Southeast Asia. 展开更多
关键词 non-solid cooking fuel nutrition benefits under-five children developing countries
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Challenges to establishing and maintaining kidney transplantation programs in developing countries:What are the coping strategies?
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作者 Rabea Ahmed Gadelkareem Amr Mostafa Abdelgawad +4 位作者 Nasreldin Mohammed Mohammed Ali Zarzour Mahmoud Khalil Ahmed Reda Hisham Mokhtar Hammouda 《World Journal of Methodology》 2024年第2期1-16,共16页
Kidney transplantation(KT)is the optimal form of renal replacement therapy for patients with end-stage renal diseases.However,this health service is not available to all patients,especially in developing countries.The... Kidney transplantation(KT)is the optimal form of renal replacement therapy for patients with end-stage renal diseases.However,this health service is not available to all patients,especially in developing countries.The deceased donor KT programs are mostly absent,and the living donor KT centers are scarce.Single-center studies presenting experiences from developing countries usually report a variety of challenges.This review addresses these challenges and the opposing strategies by reviewing the single-center experiences of developing countries.The financial challenges hamper the infrastructural and material availability,coverage of transplant costs,and qualification of medical personnel.The sociocultural challenges influence organ donation,equity of beneficence,and regular follow-up work.Low interests and motives for transplantation may result from high medicolegal responsibilities in KT practice,intense potential psychosocial burdens,complex qualification protocols,and low productivity or compensation for KT practice.Low medical literacy about KT advantages is prevalent among clinicians,patients,and the public.The inefficient organizational and regulatory oversight is translated into inefficient healthcare systems,absent national KT programs and registries,uncoordinated job descriptions and qualification protocols,uncoordinated on-site investigations with regulatory constraints,and the prevalence of commercial KT practices.These challenges resulted in noticeable differences between KT services in developed and developing countries.The coping strategies can be summarized in two main mechanisms:The first mechanism is maximizing the available resources by increasing the rates of living kidney donation,promoting the expertise of medical personnel,reducing material consumption,and supporting the establishment and maintenance of KT programs.The latter warrants the expansion of the public sector and the elimination of non-ethical KT practices.The second mechanism is recruiting external resources,including financial,experience,and training agreements. 展开更多
关键词 CHALLENGES Coping strategies developing countries Kidney transplantation Low resources Single-center
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Food Security in Developing Countries: Factors and Mitigation
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作者 Hellen Abbo Owasa Abdoulaye Fofana Fall 《American Journal of Climate Change》 2024年第3期391-405,共15页
Since 1976, eradicating hunger has become one of the priority objectives of the United Nations, which is included in the Charter of Human Rights;the right to get adequate food. The qualification of food security in ti... Since 1976, eradicating hunger has become one of the priority objectives of the United Nations, which is included in the Charter of Human Rights;the right to get adequate food. The qualification of food security in time and space must analyze not only the three components it covers but also the relationships that these three components maintain. Climate change contributes to food insecurity, but it is not the only factor. To address food insecurity in various forms, greater food security must be combined with improved sustainable agricultural practices with minimal strain on the environment. This review of literature insists on the principles of food security, which in particular allows a better understanding of food insecurity in developing countries and favors a greater contribution of agriculture and food systems in general to nutritional progress. 展开更多
关键词 Food Security developing Countries Climate Change
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Research on Developing an Assessment Scale for Tourism Experience Elements of Ancient Shu Road Heritage Trail
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作者 Wang Yuan Wang Bo Zhou Jiang 《Contemporary Social Sciences》 2024年第5期118-142,共25页
Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse them... Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse thematic variations,and considerable tourist appeal,these paths have emerged as representative heritage trails,increasingly transforming into a novel tourism product experience that is highly favored by tourists and recognized by government authorities.However,research on ancient roads for tourism in China currently lacks a systematic theoretical framework,as well as relevant policies,regulations,and standards to guide their practical development.Therefore,there is a pressing need to draw upon international best practices and conduct foundational research to develop an experience element system that aligns with the perceptions,behaviors,and consumption characteristics of Chinese tourists,thereby advancing theoretical exploration in this field.This study focuses on the representative Ancient Shu Road as a case study and employs a mixed-method approach that integrates qualitative and quantitative research.It aims to construct a tourist-centric scale for the experience elements of ancient road tourism while analyzing the interactive relationship between these experience elements and tourist needs.This study addresses a significant gap in the development of indicator systems for domestic studies of ancient road tourism experiences.Ultimately,the study establishes a comprehensive scale that encompasses three core categories—trail resources and environment,facilities and services,and modes of tourism activities—along with eight primary dimensions:core resources,surrounding cultural environment,surrounding natural environment,tourism reception facilities and services,infrastructure and support services,information facilities and information services,and outdoor and recreational activities.This scale consists of thirty-two specific items,providing a robust reference for future research endeavors.Additionally,the study proposes specific development strategies related to key mechanisms,spatial configuration,and facility construction to enhance the overall development of ancient road tourism. 展开更多
关键词 ancient roads heritage trails tourism experience elements scale development
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Towards Lessening Learners’Aversive Emotions and Promoting Their Mental Health:Developing and Validating a Measurement of English Speaking Demotivation in the Chinese EFL Context
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作者 Chili Li Xinxin Zhao +2 位作者 Ziwen Pan Ting Yi Long Qian 《International Journal of Mental Health Promotion》 2024年第2期161-175,共15页
While a plethora of studies has been conducted to explore demotivation and its impact on mental health in second language(L2)education,scanty research focuses on demotivation in L2 speaking learning.Particularly,littl... While a plethora of studies has been conducted to explore demotivation and its impact on mental health in second language(L2)education,scanty research focuses on demotivation in L2 speaking learning.Particularly,little research explores the measures to quantify L2 speaking demotivation.The present two-phase study attempts to develop and validate an English Speaking Demotivation Scale(ESDS).To this end,an independent sample of 207 Chinese tertiary learners of English as a Foreign Language(EFL)participated in the development phase,and another group of 188 Chinese EFL learners was recruited for the validation of the scale.Exploratory Factor Analysis(EFA)and Confirmatory Factor Analysis(CFA)were employed to determine the factor structure of the scale.The EFA results revealed a six-factor solution with Teacher-related Factors in Learning Spoken English(TFLSE),Interest and Valence in Learning Spoken English(IVLSE),Self-efficacy in Learning Spoken English(SELSE),Negative Peer Influence in Learning Spoken English(NPILSE),Undesirable Environment for Learning Spoken English(UELSE),and Negative Influence of Assessment and Learning Materials in speaking class(NIALM).In the validation phase,Confirmatory Factor Analysis(CFA)was performed to validate the internal structure of the scale.The CFA results showed that the model fits the data well.Overall,the ESDS is a robust and trustworthy psychometric tool that could be utilized to examine L2 speaking demotivation.Implications for diminishing EFL learners’demotivation,lessening their aversive emotions and promoting their mental health are also discussed. 展开更多
关键词 Demotivation for learning English speaking ESDS scale development and validation Chinese EFL learners mental health
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基于POA的读写结合教学实践--以外研版高中英语教材Developing Ideas板块为例 被引量:1
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作者 刘钰 张华清 《中小学英语教学与研究》 北大核心 2023年第1期49-53,共5页
读写结合是实施综合性语言学习的重要途径。产出导向法(POA)强调通过语言输入为语言输出搭建支架,有助于落实读写结合教学,实现语言文化知识的学习理解和迁移应用。本文以外研版高中英语教材Developing Ideas板块为例,阐述基于POA进行... 读写结合是实施综合性语言学习的重要途径。产出导向法(POA)强调通过语言输入为语言输出搭建支架,有助于落实读写结合教学,实现语言文化知识的学习理解和迁移应用。本文以外研版高中英语教材Developing Ideas板块为例,阐述基于POA进行高中英语读写结合教学的策略:(1)输出驱动--呈现任务、尝试写作、激发动机。(2)输入促成--以读促写、搭建支架、迁移应用。(3)以评为学--师生合作、典型分析、完善修订。在此过程中,写作任务设计、阅读文本的选择等都有所要求。 展开更多
关键词 POA 读写结合教学 外研版developing ideas板块
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Selection and Validation of Reference Genes for Normalization of RT-qPCR Analysis in Developing or Abiotic-Stressed Tissues of Loquat (Eriobotrya japonica) 被引量:1
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作者 Shoukai Lin Shichang Xu +6 位作者 Liyan Huang Fuxiang Qiu Yihong Zheng Qionghao Liu Shiwei Ma Bisha Wu Jincheng Wu 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第4期1185-1201,共17页
Loquat(Eriobotrya japonica Lindl.)is a subtropical evergreen fruit tree that produces fruits with abundant nutrients and medicinal components.Confirming suitable reference genes for a set of loquat samples before qRT-... Loquat(Eriobotrya japonica Lindl.)is a subtropical evergreen fruit tree that produces fruits with abundant nutrients and medicinal components.Confirming suitable reference genes for a set of loquat samples before qRT-PCR experiments is essential for the accurate quantification of gene expression.In this study,eight candidate reference genes were selected from our previously published RNA-seq data,and primers for each candidate reference gene were designed and evaluated.The Cq values of the candidate reference genes were calculated by RT-qPCR in 31 different loquat samples,including 12 subgroups of developing or abiotic-stressed tissues.Different combinations of stable reference genes were screened according to a comprehensive rank,which was synthesized from the results of four algorithms,including the geNorm,NormFinder,BestKeeper andΔCt methods.The screened reference genes were verified by normalizing EjLGA1 in each subgroup.The obtained suitable combinations of reference genes for accurate normalization were GAPDH,EF1αand ACT for floral development;GAPDH,UBCE and ACT for fruit setting;EF1α,GAPDH and eIF2B for fruit ripening;ACT,EF1αand UBCE for leaves under heat stress;eIF2B,UBCE and EF1αfor leaves under freezing stress;EF1α,TUA and UBCE for leaves under salt stress;ACT,EF1αand eIF2B for immature pulp under freezing stress;ACT,UBCE and eIF2B for immature seeds under freezing stress;EF1α,eIF2B and UBCE for both immature pulp and seeds under freezing stress;UBCE,TUB and TUA for red-fleshed fruits under cold-storage stress;eIF2B,RPS3 and TUB for white-fleshed fruits under coldstorage stress;and eIF2B,UBCE and RPS3 for both red-and white-fleshed fruits under cold-storage stress.This study obtained different combinations of stable reference genes for accurate normalization in twelve subgroups of developing or abiotic-stressed tissues in loquat.To our knowledge,this is the first report to obtain stable reference genes for normalizing gene expression of abiotic-stressed tissues in E.japonica.The use of the three most stable reference genes could increase the reliability of future quantification experiments. 展开更多
关键词 LOQUAT Eriobotrya japonica reference genes qRT-PCR gene expression NORMALIZATION developing tissues abiotic-stressed tissues
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The molecular mechanism of WRINKLED1 transcription factor regulating oil accumulation in developing seeds of castor bean
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作者 Qing Tan Bing Han +5 位作者 Mohammad Enamul Haque Ye-Lan Li Yue Wang Di Wu Shi-Bo Wu Ai-Zhong Liu 《Plant Diversity》 SCIE CAS CSCD 2023年第4期469-478,共10页
The transcription factor WRINKLED1(WRI1),a member of AP2 gene family that contain typical AP2 domains,has been considered as a master regulator regulating oil biosynthesis in oilseeds.However,the regulatory mechanism ... The transcription factor WRINKLED1(WRI1),a member of AP2 gene family that contain typical AP2 domains,has been considered as a master regulator regulating oil biosynthesis in oilseeds.However,the regulatory mechanism of RcWRI1 in regulating oil accumulation during seed development has not been clearly addressed.Castor bean(Ricinus communis)is one of the most important non-edible oil crops and its seed oils are rich in hydroxy fatty acids,widely applied in industry.In this study,based on castor bean reference genome,three RcWRIs genes(RcWRI1,RcWRI2 and RcWRI3)were identified and the expressed association of RcWRI1 with oil accumulation were determined.Heterologous transformation of RcWRI1 significantly increased oil content in tobacco leaf,confirming that RcWRI1 activate lipid biosynthesis pathway.Using DNA Affinity Purification sequencing(DAP-seq)technology,we confirmed RcWRI1 binding with Transcription Start Site of genes and identified 7961 WRI1-binding candidate genes.Functionally,these identified genes were mainly involved in diverse metabolism pathways(including lipid biosynthesis).Three cis-elements AW-box([CnTnG](n)7[CG])and AW-boxes like([GnAnC](n)6[GC]/[GnAnC](n)7[G])bound with RcWRI1 were identified.Co-expression network analysis of RcWRI1 further found that RcWRI1 might be widely involved in biosynthesis of storage materials during seed development.In particular,yeast one hybrid experiments found that both AP2 domains within RcWRI1 were required in binding targeted genes.These results not only provide new evidence to understand the regulatory mechanism of RcWRI1 in regulation of oil accumulation during castor bean seed development,but also give candidate gene resource for subsequent genetic improvement toward increasing oil content in oilseed crops. 展开更多
关键词 Castor bean WRI transcription factor Oil accumulation developing seeds Lipid gene
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The barriers of joining in vitro fertilization programs among infertile couples in developing countries:A scoping review
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作者 Andriana K Dewi Anggi L Wicaksana +1 位作者 Muhammad Lutfi Agung Dewanto 《Asian pacific Journal of Reproduction》 2023年第4期147-154,I0001-I0003,共11页
Objective:To determine the barriers of joining in-vitro fertilization(IVF)programs among infertile couples in developing countries.Methods:This study assessed infertile couples and the barriers or associated factors r... Objective:To determine the barriers of joining in-vitro fertilization(IVF)programs among infertile couples in developing countries.Methods:This study assessed infertile couples and the barriers or associated factors resulting in delayed decision-making of joining IVF program by searching databases PubMed,ScienceDirect,EBSCO,ClinicalKey,and Cochrane Library from inception until December 31,2021.Additional search strategies were snowballing literature search and citation tracking.Results:Eleven articles were included in the scoping review.The cost was the greatest barrier of joining IVF program.Limited access and lack of assisted reproductive technology centers,few qualified infertility trained staff,insufficient government support,low priority in government policy,along with sociocultural factors,such as religion and false beliefs or myths were also majorly considered to be associated obstacles.Conclusions:The main barrier associated with IVF program among infertile couples in developing countries is the high cost of the IVF services. 展开更多
关键词 In vitro fertilization Assisted reproductive technology BARRIER developing countries
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Environmental Impact Assessment System and Process in Developing Countries
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作者 Ramesh Prasad Bhatt 《Open Journal of Ecology》 2023年第12期977-1009,共33页
Environmental impact assessment (EIA), a decision-making process for project appraisal and sustainability adopted globally as an administrative process to identify, predict, evaluate, and monitor projects from their f... Environmental impact assessment (EIA), a decision-making process for project appraisal and sustainability adopted globally as an administrative process to identify, predict, evaluate, and monitor projects from their feasibility, preconstruction, construction, and operation stages to mitigate the adverse impacts and enhance the beneficial impacts for the protection of the affected environment, The study objective is to explore global EIA systems and processes and find shortcomings and implications for making the best instrument or tool to protect the natural environment from man-made activities over the project cycle. For this, the relevant literature on the EIA system and process was reviewed and evaluated through the application of quantitative and qualitative approaches, including the assessment of legal instruments and the adoption of EIA methodologies in developing countries. EIA, initiated in the 1970s in the US and Australia, expanded to developing countries and was amended in East and Southeast Asia from the 1970s to the 2000s. The evaluation assessed that the South Asian countries follow UNEP and IAIA guidelines, utilizing national laws and expert consultations, with screening criteria and administrative processes based on established environmental legislation. Ad hoc, checklist, matrix, network, overlay, cost-benefit analysis, and predictive or simulation in EIA practice are used to assess the environmental impacts of development activities. Failure to recommend major projects undermines public trust and prevents mitigation measures from being implemented. Most developing countries have followed EIA to fulfill the legal requirement with shadow-off monitoring and follow-up rather than to upset, reduce, or compensate for the project impacts as per size, location, and severity of the project area. The research and guidelines outlined in the IAIA principles and process have synthesized the best EIA practices worldwide. Public participation, impact coverage, scientific mitigation, transparent evidence-based approaches, monitoring, follow-up, legitimate approaches, and future appraisal opportunities are major concerns to be included in best EIA practice. 展开更多
关键词 EIA Process and Practice Evolution developing Countries Legal Instruments IMPLICATIONS
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Digital Development Rights in Developing Countries:Where the Governance Rules for Cross-Border Data Flows
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作者 李艳华 JIANG Yu(译) 《The Journal of Human Rights》 2023年第5期1040-1066,共27页
The digital development rights in developing countries are based on establishing a new international economic order and ensuring equal participation in the digital globalization process to achieve people's well-ro... The digital development rights in developing countries are based on establishing a new international economic order and ensuring equal participation in the digital globalization process to achieve people's well-rounded development in the digital society.The relationship between cross-border data flows and the realization of digital development rights in developing countries is quite complex.Currently,developing countries seek to safeguard their existing digital interests through unilateral regulation to protect data sovereignty and multilateral regulation for cross-border data cooperation.However,developing countries still have to face internal conflicts between national digital development rights and individual and corporate digital development rights during the process of realizing digital development rights.They also encounter external contradictions such as developed countries interfering with developing countries'data sovereignty,developed countries squeezing the policy space of developing countries through dominant rules,and developing countries having conflicts between domestic and international rules.This article argues that balancing openness and security on digital trade platforms is the optimal solution for developing countries to realize their digital development rights.The establishment of WTO digital trade rules should inherently reflect the fundamental demands of developing countries in cross-border data flows.At the same time,given China's dual role as a digital powerhouse and a developing country,it should actively promote the realization of digital development rights in developing countries. 展开更多
关键词 developing countries digital development rights cross-border data flows governance rules
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Developing Projects with Low-code Combined with ChatGPT
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作者 Wei Xiong Bing Li +1 位作者 Zhao Wu Bo Hang 《计算机教育》 2023年第12期204-213,共10页
This paper aims to explore a simpler and more user-friendly way of generating software based on model-driven development.Previous studies have attempted to generate code from domain models,hoping to reduce coding time... This paper aims to explore a simpler and more user-friendly way of generating software based on model-driven development.Previous studies have attempted to generate code from domain models,hoping to reduce coding time by increasing modeling time.However,as code tools become more advanced,it is challenging to improve efficiency because models are abstract while implementations are concrete.This paper proposes a novel approach that integrates ChatGPT as a plug-in into the whole R&D process and combines it with our code generation tool to enhance R&D efficiency.We have developed some demos to demonstrate the effectiveness of our approach.According to our evaluation,our approach can save more than 90%of the work in implementing the code generation tool,leaving only about 10%of the work for code review,code improvement,and unit testing. 展开更多
关键词 ChatGPT Low-code Code generation Software engineering Project development
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Linking Competitors’ Knowledge and Developing Innovative Products Using Data Mining Techniques
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作者 Nasimalsadat Saesi Mohammad Taleghani 《Journal of Computer and Communications》 2023年第7期37-57,共21页
In this article, the relationship between the knowledge of competitors and the development of new products in the field of capital medical equipment has been investigated. In order to identify the criteria for measuri... In this article, the relationship between the knowledge of competitors and the development of new products in the field of capital medical equipment has been investigated. In order to identify the criteria for measuring competitors’ knowledge and developing new capital medical equipment products, marketing experts were interviewed and then a researcher-made questionnaire was compiled and distributed among the statistical sample of the research. Also, in order to achieve the goals of the research, a questionnaire among 100 members of the statistical community was selected, distributed and collected. To analyze the gathered data, the structural equation modeling (SEM) method was used in the SMART PLS 2 software to estimate the model and then the K-MEAN approach was used to cluster the capital medical equipment market based on the knowledge of actual and potential competitors. The results have shown that the knowledge of potential and actual competitors has a positive and significant effect on the development of new products in the capital medical equipment market. From the point of view of the knowledge of actual competitors, the market of “MRI”, “Ultrasound” and “SPECT” is grouped in the low knowledge cluster;“Pet MRI”, “CT Scan”, “Mammography”, “Radiography, Fluoroscopy and CRM”, “Pet CT”, “SPECT CT” and “Gamma Camera” markets are clustered in the medium knowledge. Finally, “Angiography” and “CBCT” markets are located in the knowledge cluster. From the perspective of knowledge of potential competitors, the market of “angiography”, “mammography”, “SPECT” and “SPECT CT” in the low knowledge cluster, “CT scan”, “radiography, fluoroscopy and CRM”, “pet CT”, “CBCT” markets in the medium knowledge cluster and “MRI”, “pet MRI”, “ultrasound” and “gamma camera” markets in the high knowledge cluster are located. 展开更多
关键词 Knowledge of Competitors Development of Products Innovative Products Data Mining Data Mining Techniques Medical Capital Goods Medical Capital Goods Market
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Status quo of Agriculture in Benin and Developing Strategy
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作者 刘开强 韦宇 +4 位作者 李孝琼 陈颖 郭嗣斌 黄玉溢 高国庆 《Agricultural Science & Technology》 CAS 2015年第4期777-781,共5页
Benin, a tropical country in west Africa, is one of the Ieast deveIoped countries confirmed by the United Nations. Benin is highIy dependent on agricuIture and reIativeIy rich in agricuIture resources. It&#39;s espec... Benin, a tropical country in west Africa, is one of the Ieast deveIoped countries confirmed by the United Nations. Benin is highIy dependent on agricuIture and reIativeIy rich in agricuIture resources. It&#39;s especial y suitabIe for agricuIture be-cause of the sufficient sunIight, raln and suitabIe temperature. AgricuIture export in Benin pIays an important part for both government and farmers. But the Iack of new varieties, appropriate technoIogy and modern service makes it difficuIt to deveI-op the agricuIture production rapidIy. Based on the introduction of agricuIture re-sources incIuding cIimate and Iand, this articIe malnIy showed the maln agricuIture productions and potential probIems in Benin, and then Iooked into the distance and deveIoping strategy on how to soIve the probIems. In order to deveIop the agricuI-ture sustalnabIy in Benin, it’s also suggested that the worId shouId strengthen the ald and share the fruits of new products, appropriate technoIogy and good man-agement methods. 展开更多
关键词 AgricuIture STATUS developing strategles BENIN
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Exploration and Practice of Developing Hybrid Rice for Realizing Food Self-sufficiency in East Timor 被引量:1
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作者 方远祥 唐启源 +2 位作者 李迪秦 张建华 黄大辉 《Agricultural Science & Technology》 CAS 2011年第11期1617-1620,F0003,共5页
The status, advantages and disadvantages of rice production in East Timor were investigated and analyzed, the results of comparison test and demonstrative cultivation through introducing 15 Chinese hybrid rice combina... The status, advantages and disadvantages of rice production in East Timor were investigated and analyzed, the results of comparison test and demonstrative cultivation through introducing 15 Chinese hybrid rice combinations into East Timor were summarized, the feasibility of developing hybrid rice in East Timor to realize food self-sufficiency were discussed and demonstrated, and the main corresponding technical strategies were proposed in this paper. 展开更多
关键词 East Timor Hybrid rice Demonstrative performance developing strategies
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Ultrastructure of Epidermis and Flesh of the Developing Apple Fruit 被引量:16
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作者 彭宜本 张大鹏 《Acta Botanica Sinica》 CSCD 2000年第8期794-802,共9页
The ultrastructure of the epidermis and flesh of apple ( Malus domestica Borkh cv. Red Fuji) fruit was systematically observed during the fruit development via transmission electron microscopy. The results showed t... The ultrastructure of the epidermis and flesh of apple ( Malus domestica Borkh cv. Red Fuji) fruit was systematically observed during the fruit development via transmission electron microscopy. The results showed that, in spite of the ultrastructural changes in many aspects of the developing fruit epidermal cells, it remained almost unchanged throughout the whole developmental process that the cytoplasm was filled with numerous endoplasmic reticula (ER). Most of these endoplasmic reticula were tube_like and rough_ER with enlarged cisterna from which many vesicles were produced. Some of the vesicles were shown to merge into vacuole. Some dynamic Golgi bodies were also found. All the ultrastructural characteristics showed that the epidermal cells have the features of excretory cells. The ultrastructure of the fruit flesh cells at the young fruit stage were shown to be metabolically active, characterized by the presence of numerous clustered plasmodesmata, cisterna enlarged_ and rough_ER filling the cytoplasm, plenty of vesicles and Golgi bodies, indicating their dynamic cellular transport function. Some giant_circular rough_ERs were found. All the ultrastructural features at this early developmental stage should be closely associated with the enlargement of the young fruit. At the rapid growing phase of the fruit the main changes were characterized by: the starch grain_filled amyloplasts, furcating of the single orifice of plasmodesmata, and the cytoplasm enrichment of both the Golgi body_formed vesicles and other vesicles. These features correspond well with those of a photoassimilate sink_cell. An ultrastructural degeneration phenomenon was observed at the fruit ripening stage, but the mitochondria and plasmalemma still remained intact, which might be related to the continuous development of fruit quality during the fruit ripening. 展开更多
关键词 APPLE FRUIT EPIDERMIS FLESH ULTRASTRUCTURE fruit development
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Hepatitis B:Epidemiology and prevention in developing countries 被引量:41
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作者 Elisabetta Franco Barbara Bagnato +3 位作者 Maria Giulia Marino Cristina Meleleo Laura Serino Laura Zaratti 《World Journal of Hepatology》 CAS 2012年第3期74-80,共7页
Hepatitis B virus(HBV)infection is a serious global public health problem.The infection may be transmitted through sexual intercourse,parenteral contact or from an infected mother to the baby at birth and,if contracte... Hepatitis B virus(HBV)infection is a serious global public health problem.The infection may be transmitted through sexual intercourse,parenteral contact or from an infected mother to the baby at birth and,if contracted early in life,may lead to chronic liver disease,including cirrhosis and hepatocellular carcinoma.On the basis of the HBV carrier rate,the world can be divided in 3 regions of high,medium and low endemicity.The major concern is about high endemicity countries,where the most common route of infection remains vertical transmission from mother to child.Screening of all pregnant women and passive immunization with human hepatitis B immunoglobulin are not affordable for many developing countries.The infection rate can be reduced by modifying behavior,improving individual education,testing all blood donations,assuring asepsis in clinical practice and screening all pregnant women.However,availability of a safe and efficacious vaccine and adoption of appropriate immunization strategies are the most effective means to prevent HBV infection and its consequences.The unsolved problem for poorest countries,where the number of people currently infected is high,is the cost of the vaccine.A future challenge is to overcome the social and economic hurdles of maintaining and improving a prevention policy worldwide to reduce the global burden of the disease. 展开更多
关键词 HEPATITIS B developing COUNTRIES ENDEMICITY SEROPREVALENCE VACCINE
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Epidemiological transition of colorectal cancer in developing countries: Environmental factors, molecular pathways, and opportunities for prevention 被引量:19
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作者 Faraz Bishehsari Mahboobeh Mahdavinia +2 位作者 Michele Vacca Reza Malekzadeh Renato Mariani-Costantini 《World Journal of Gastroenterology》 SCIE CAS 2014年第20期6055-6072,共18页
Colorectal cancer(CRC)is one of the leading causes of cancer and cancer-related mortality worldwide.The disease has been traditionally a major health problem in industrial countries,however the CRC rates are increasin... Colorectal cancer(CRC)is one of the leading causes of cancer and cancer-related mortality worldwide.The disease has been traditionally a major health problem in industrial countries,however the CRC rates are increasing in the developing countries that are undergoing economic growth.Several environmental risk factors,mainly changes in diet and life style,have been suggested to underlie the rise of CRC in these populations.Diet and lifestyle impinge on nuclear receptors,on the intestinal microbiota and on crucial molecular pathways that are implicated in intestinal carcinogenesis.In this respect,the epidemiological transition in several regions of the world offers a unique opportunity to better understand CRC carcinogenesis by studying the disease phenotypes and their environmental and molecular associations in different populations.The data from these studies may have important implications for the global prevention and treatment of CRC. 展开更多
关键词 Colorectal cancer developing countries Environment DIET Nuclear receptors Gut microbiota
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Hepatitis A:Epidemiology and prevention in developing countries 被引量:20
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作者 Elisabetta Franco Cristina Meleleo +2 位作者 Laura Serino Debora Sorbara Laura Zaratti 《World Journal of Hepatology》 CAS 2012年第3期68-73,共6页
Hepatitis A is the most common form of acute viral hepatitis in the world.Major geographical differences in endemicity of hepatitis A are closely related to hygienic and sanitary conditions and other indicators of the... Hepatitis A is the most common form of acute viral hepatitis in the world.Major geographical differences in endemicity of hepatitis A are closely related to hygienic and sanitary conditions and other indicators of the level of socioeconomic development.The anti-hepatitis A virus(HAV)seroprevalence rate is presently decreasing in many parts of the world,but in less developed regions and in several developing countries,HAV infection is still very common in the first years of life and seroprev-alence rates approach 100%.In areas of intermediate endemicity,the delay in the exposure to the virus has generated a huge number of susceptible adolescents and adults and significantly increased the average age at infection.As the severity of disease increases with age,this has led to outbreaks of hepatitis A.Several factors contribute to the decline of the infection rate,including rising socioeconomic levels,increased access to clean water and the availability of a hepatitis A vaccine that was developed in the 1990s.For populations with a high proportion of susceptible adults,implementing vaccination programs may be considered.In this report,we review available epidemiological data and implementation of vaccination strategies,particularly focusing on developing countries. 展开更多
关键词 HEPATITIS A developing COUNTRIES Endemic-ity SEROPREVALENCE VACCINE
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Comparative analysis of open and laparoscopic colectomy for malignancy in a developing country 被引量:9
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作者 Pierre-Anthony Leake Kristen Pitzul +1 位作者 Patrick O Roberts Joseph M Plummer 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2013年第11期294-299,共6页
AIM: To compare the short-term, including oncologic, outcomes of open vs laparoscopic colectomy for cancer in a developing country. METHODS: The records of patients who underwent elective open and laparoscopic colecto... AIM: To compare the short-term, including oncologic, outcomes of open vs laparoscopic colectomy for cancer in a developing country. METHODS: The records of patients who underwent elective open and laparoscopic colectomies for cancer at the University Hospital of the West Indies between January 2005 and December 2010 were retrospectively reviewed. Demographic(age, gender, Charlson comorbidity index score), peri-operative, post-operative and oncologic data were collected for each patient. Specific oncologic variables included lymph node yield, pathologic stage, grade, proximal, distal and circumferential margin involvement. Fisher's exact, Mann-Whitney, and binary logistic regression tests were used for analysis. Significance level was set atP < 0.05. RESULTS: There were 87 cases for open colectomy(OC) and 17 cases for laparoscopic colectomy(LC). Demographics did not significantly differ between OC and LC groups. Intra-operative blood loss and postoperative analgesic requirements did not significantly differ between groups. There was a trend towards longer operating times in OC group and shorter hospital stay in the LC group. Lymph node yield(14 vs 14, P = 0.619), proximal(10 cm vs 7 cm, P = 0.353) and distal(8 cm vs 8 cm, P = 0.57) resection margin distance and circumferential margin involvement(9 vs 0, P = 0.348) did not significantly differ between groups. Thirty-day morbidity was equivalent between groups(22 vs 6, P = 0.774). There were 6 deaths within 30 d of initial procedure, all in the OC group(6.9%). CONCLUSION: Laparoscopic colectomy in a developing country is oncologically safe and represents a option for colonic malignancies in these regions. Such data encourage the continued laparoscopic development. 展开更多
关键词 LAPAROSCOPY COLECTOMY Cancer developing COUNTRY COLORECTAL ONCOLOGY Short-term Outcomes
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