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Effects of Different Application Times of Tillering Fertilizer on Grain Yield and Population Development of Double-cropping Rice Transplanted by Machine
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作者 商庆银 吕伟生 +5 位作者 曾勇军 黄山 杨秀霞 谭雪明 石庆华 潘晓华 《Agricultural Science & Technology》 CAS 2015年第9期1860-1864,1868,共6页
The application of tillering fertilizer plays an important role in promoting rice tillering and improving rice yield. However, under the condition of mechanical transplanting, the optimal application time of tillering... The application of tillering fertilizer plays an important role in promoting rice tillering and improving rice yield. However, under the condition of mechanical transplanting, the optimal application time of tillering fertilizer is still unclear. In this study, the early rice cultivar Zhongjiazao 17 and late rice cultivar H You 518 were used as materials, and the effects of different application times of tillering fertilizer on yield and population development of double-cropping rice transplanted by machine were investigated. The tillering fertilizer was applied 7(D07), 10(D10) and 13(D13) d after the transplanting, respectively. The results showed that compared with those in the D07 treatment groups, the yield of early rice in the D10 and D13 treatment groups were reduced by 9.4% and 3.8%, respectively, and the yield of late rice in the D10 and D13 treatment groups were reduced by 4.5% and 12.6%,respectively. However, there were no significant differences in rice yield among the treatment groups. The application time of tillering fertilizer showed significant effects on grain number per panicle and seed setting rate of early rice. The grain number per panicle in the D10 treatment group was significantly lower than that in the D07 treatment group, and the seed setting rate of the D13 treatment group was significantly lower than that in the D07 treatment group(P〈0.05). For the late rice, the effect of application time of tillering fertilizer on effective tiller number was most obvious, and the effective tiller number in the D13 treatment group was significantly lower than that in the D07 treatment group(P〈0.05). Compared with those in the D07 treatment group, the effective tiller numbers, leaf area indexes and biomasses in the D10 and D13 treatment groups were all trended to be decreased. Therefore,to improve the quality of population and fulfill the high-yielding potential of double-cropping rice transplanted by machine, the tillering fertilizer should be applied as early as possible after rice seedlings turn green. 展开更多
关键词 Double-cropping rice Mechanical transplanting Tillering fertilizer Application time YIELD Population development
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Effects of Nitrogen Application Time on Caryopsis Development and Grain Quality of Rice Variety Yangdao 6 被引量:13
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作者 XIONG Fei WANG Zhong Gu Yun-jie CHEN Gang ZHOU Peng 《Rice science》 SCIE 2008年第1期57-62,共6页
A pot experiment was conducted to study the effects of different nitrogen application time (during the tillering or the booting stages) with the same nitrogen rates on the caryopsis development and grain quality of ... A pot experiment was conducted to study the effects of different nitrogen application time (during the tillering or the booting stages) with the same nitrogen rates on the caryopsis development and grain quality of rice variety Yangdao 6. The increased nitrogen fertilizer (urea), especially applied during the booting stage, could evidently increase the milled rice rate, head rice rate and protein content in rice grains compared with the control (no nitrogen application), and decrease chalky grain rate and amylose content. Moreover, the increased nitrogen fertilizer significantly affected the caryopsis development and enhanced the grain weight when nitrogen applied during the tillering and the booting stages, especially during the booting stage. During caryopsis development the increased nitrogen fertilizer applied during the tillering and booting stages could obviously decrease the total starch and amylose contents, but not obviously for the amylopectin content in rice grain. Increased topdressing of nitrogen fertilizer, especially applied during the booting stage, had significant effect on the development and structures of amyloplasts and proteinoplasts. That is, it could change the distribution, number and shape of amyloplasts and proteinoplasts in the endosperm cells especially in grain abdomen, Compared with the control the arrangements of amyloplasts and proteinoplasts were closer, with more numbers, higher density and less interspaces each ohter. Furthermore, most amyloplasts showed polyhedron under the increased nitrogen fertilizer level. 展开更多
关键词 caryopsis development rice quality AMYLOSE proteinoplast AMYLOPLAST STARCH nitrogen fertilizer fertilizer application time
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The IDD Transcription Factors:Their Functions in Plant Development and Environmental Response
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作者 Jing Liu Defeng Shu +5 位作者 Zilong Tan Mei Ma Huanhuan Yang Ning Guo Shipeng Li Dayong Cui 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第1期63-79,共17页
INDETERMINATE-DOMAIN proteins(IDDs)are a plant-specific transcription factor family characterized by a conserved ID domain with four zinc finger motifs.Previous studies have demonstrated that IDDs coordinate a diversi... INDETERMINATE-DOMAIN proteins(IDDs)are a plant-specific transcription factor family characterized by a conserved ID domain with four zinc finger motifs.Previous studies have demonstrated that IDDs coordinate a diversity of physiological processes and functions in plant growth and development,including floral transition,plant architecture,seed and root development,and hormone signaling.In this review,we especially summarized the latest knowledge on the functions and working models of IDD members in Arabidopsis,rice,and maize,particularly focusing on their role in the regulatory network of biotic and abiotic environmental responses,such as gravity,temperature,water,and pathogens.Understanding these mechanisms underlying the function of IDD proteins in these processes is important for improving crop yields by manipulating their activity.Overall,the review offers valuable insights into the functions and mechanisms of IDD proteins in plants,providing a foundation for further research and potential applications in agriculture. 展开更多
关键词 INDETERMINATE DOMAIN flowering time root development shoot gravitropism plant immunity hormonal signaling environmental responses
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Evaluation of reference genes for quantitative real-time PCR analysis of gene expression during early development processes of the tongue sole(Cynoglossus semilaevis) 被引量:3
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作者 MA Qian ZHUANG Zhimeng +2 位作者 FENG Wenrong LIU Shufang TANG Qisheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第10期90-97,共8页
Differential expression of genes is crucial to growth and development of fish. To select the appropriate genes for gene normalization during Cynoglossus semilaevis early developmental process, eight candidate referenc... Differential expression of genes is crucial to growth and development of fish. To select the appropriate genes for gene normalization during Cynoglossus semilaevis early developmental process, eight candidate reference genes (ACTB, B2M, EF1A, GADPH, RPL7, TUBA, UBCE and 18S) were tested for their adequacy by using quantitative real-time PCR. The results showed that the expression of all the examined genes exhibited tissue dependent variations in the mature C. semilaevis. EFIA was listed as the most stable reference among the 14 tissues by RefFinder. Furthermore, the recommended comprehensive ranking of the stability determined by RefFinder showed that 18S was the most stable gene during the early developmental stages (from oosphere to 90 days old) in this study. However, when divided the Ct value data of the above mentioned early developmental stages into two separate periods (embryo and post-hatching periods), TUBA and 18S represented the most stable references of these two developmental periods, respectively. Consequently, the reference gene should be carefully and accurately chosen even for studies of the same species at various developmental processes. The relevant data may help in selecting appropriate reference genes for mRNA expression analysis, and is of great value in the studies of fish growth and development. 展开更多
关键词 quantitative real-time PCR reference gene early development Cynoglossus semilaevis
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Egg Development Time (EDT) in <i>Mesocyclops ogunnus</i>
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作者 Moshe Gophen 《Open Journal of Modern Hydrology》 2018年第1期28-37,共10页
A study was carried out on the impacts of temperature and light/dark regime on the Egg Development Time (EDT) of the cyclopoida copepod, Mesocyclops ogunnus in Lake Kinneret. It was found that EDT was 148, 33 and 20 h... A study was carried out on the impacts of temperature and light/dark regime on the Egg Development Time (EDT) of the cyclopoida copepod, Mesocyclops ogunnus in Lake Kinneret. It was found that EDT was 148, 33 and 20 hours under 15°C, 22°C, and 27°C respectively. EDT was different between the two regimes of 12/12 hrs light/dark and 24 hrs light. Egg hatching and survival were higher under 24 hrs light regime. The results of temperature and light regime impacts on EDT indicate ecological implication on cyclopoida copepod population dynamics in lakes. The implication of the results to the global warming trend is also suggested. 展开更多
关键词 development EGGS Kinneret MESOCYCLOPS time
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Regional Economic Development Trend Prediction Method Based on Digital Twins and Time Series Network
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作者 Runguo Xu Xuehan Yu Xiaoxue Zhao 《Computers, Materials & Continua》 SCIE EI 2023年第8期1781-1796,共16页
At present,the interpretation of regional economic development(RED)has changed from a simple evaluation of economic growth to a focus on economic growth and the optimization of economic structure,the improvement of ec... At present,the interpretation of regional economic development(RED)has changed from a simple evaluation of economic growth to a focus on economic growth and the optimization of economic structure,the improvement of economic relations,and the change of institutional innovation.This article uses the RED trend as the research object and constructs the RED index to conduct the theoretical analysis.Then this paper uses the attention mechanism based on digital twins and the time series network model to verify the actual data.Finally,the regional economy is predicted according to the theoretical model.The specific research work mainly includes the following aspects:1)This paper introduced the development status of research on time series networks and economic forecasting at home and abroad.2)This paper introduces the basic principles and structures of long and short-term memory(LSTM)and convolutional neural network(CNN),constructs an improved CNN-LSTM model combined with the attention mechanism,and then constructs a regional economic prediction index system.3)The best parameters of the model are selected through experiments,and the trained model is used for simulation experiment prediction.The results show that the CNN-LSTM model based on the attentionmechanism proposed in this paper has high accuracy in predicting regional economies. 展开更多
关键词 Regional economic development attention mechanism digital twins time series network
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Knowledge Management of Software Productivity and Development Time
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作者 James A. Rodger Pankaj Pankaj Ata Nahouraii 《Journal of Software Engineering and Applications》 2011年第11期609-618,共10页
In this paper, we identify a set of factors that may be used to forecast software productivity and software development time. Software productivity was measured in function points per person hours, and software develo... In this paper, we identify a set of factors that may be used to forecast software productivity and software development time. Software productivity was measured in function points per person hours, and software development time was measured in number of elapsed days. Using field data on over 130 field software projects from various industries, we empirically test the impact of team size, integrated computer aided software engineering (ICASE) tools, software development type, software development platform, and programming language type on the software development productivity and development time. Our results indicate that team size, software development type, software development platform, and programming language type significantly impact software development productivity. However, only team size significantly impacts software development time. Our results indicate that effective management of software development teams, and using different management strategies for different software development type environments may improve software development productivity. 展开更多
关键词 SOFTWARE Engineering SOFTWARE Metrics FOURTH Generation LANGUAGES CASE TOOLS Field Study TOOLS And Techniques Models And Principles Team Size VOLATILITY development Platform And Type Productivity Elapsed development time
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The Time Horizon in the Evaluation of Sustainable Development
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作者 Manila De Iuliis Peter Brandon 《Journal of Civil Engineering and Architecture》 2012年第3期334-343,共10页
Current methods of evaluating long term Sustainable Development seldom take into account the time period over which an evaluation is made except through simplistic economic models which heavily discount the future. If... Current methods of evaluating long term Sustainable Development seldom take into account the time period over which an evaluation is made except through simplistic economic models which heavily discount the future. If sustainable development is to be a serious issue then the impact on the future of decisions made today must be properly assessed and evaluated. This requires a new understanding of time as a key feature of the Sustainability debate and new models of how this new understanding can be brought into the evaluation process. This was at the heart of the Torino declaration signed by the University organisations of the G8, G20 and developing nations in April 2009. Time is a critical part of the sustainability debate and is seldom addressed directly. This paper will provide a possible solution based on a strong theoretical and philosophical framework of how this difficult subject can be approached and applied to sustainable urban planning. The work presented is based on a philosophical model of the cosmos which has both internal and external credibility. It forms the basis ofa PhD study and has been applied to small case studies in Italy and elsewhere. These will be presented to encourage further study into this important area within the evaluation and assessment of sustainable development. 展开更多
关键词 time sustainable development sustainable urban planning temporal analysis.
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The Development of Arbitration Cause Should be Marched Forward With Times
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作者 YU Xiao song 《China's Foreign Trade》 2001年第12期4-4,共1页
It’s a golden season of harvest during which it was a fine autumn weather with the pale clouds and a light breeze blowing in September in Beijing. The China International Economic and Trade Arbitration Commission and... It’s a golden season of harvest during which it was a fine autumn weather with the pale clouds and a light breeze blowing in September in Beijing. The China International Economic and Trade Arbitration Commission and China Maritime Arbitration Commission held a forum of arbitrators on 26 to 28 September 2001s dealing with arbitrate work in a beautiful landscape place, Kuan Gou, a suburb in Beijing. Mr. Yu Xiaosong, the Chair- man of China Council for Promotion of International Trade/China Chamber of International Commerce, China Intemational Economic and Trade Arbitration Commission and China Maritime Arbitration Commission, gave a talk at the forum stressed that the development of arbitration cause in China should be marched with ticccccccccmes and adapted to the fast development in the situations both of home and abroad. Mr. Yu Xaosong’s talk put forward a kind of principles for the development of the arbitration cause in China, a part of which, we publish part of it here as a reference for the arbitrate circle colleagues. 展开更多
关键词 The development of Arbitration Cause Should be Marched Forward With times more WTO APEC
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Is it time to rethink the Alzheimer's disease drug development strategy by targeting its silent phase?
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作者 Benoit Souchet Mickael Audrain +3 位作者 Baptiste Billoir Laurent Lecanu Satoru Tada Jérome Braudeau 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第2期224-225,共2页
Alzheimer's disease (AD) is the most frequent cause of dementia in the western world. In clinical terms, AD is characterized by progres- sive cognitive decline that usually begins with memory impairment. As the dis... Alzheimer's disease (AD) is the most frequent cause of dementia in the western world. In clinical terms, AD is characterized by progres- sive cognitive decline that usually begins with memory impairment. As the disease progresses, AD inevitably affects all intellectual functions including executive functions, leading to complete dependence for basic activities of daily life and premature death. 展开更多
关键词 AD Is it time to rethink the Alzheimer’s disease drug development strategy by targeting its silent phase
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Embryonic skeleton development and neonatal learning and memory ability of rats anesthetized with pentobarbital sodium: Differences of administration occasion and time
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作者 Changling Peng Yuhua Zhu Ankang Hu Xiaorong Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第9期844-846,共3页
BACKGROUND: Generally speaking, anesthesia is often used in gravid body and it has been already proved that many kind of medicine can result in malformation. OBJECTIVE: To explore embryonic skeleton development and ne... BACKGROUND: Generally speaking, anesthesia is often used in gravid body and it has been already proved that many kind of medicine can result in malformation. OBJECTIVE: To explore embryonic skeleton development and neonatal learning and memory of rats anesthetized with pentobarbital sodium in gravid rats. DESIGN: A randomized control trial. SETTING: Laboratory Animal Center of Xuzhou Medical College. MATERIALS: A total of 80 adult female SD rats, of clean grade and weighing 220-240 g, were selected in this study. The main reagents were detailed as follows: pentobarbital sodium (Shanghai Xingzhi Chemical Plant, batch number: 921019); MG-2 maze test apparatus (Zhangjiagang Biomedical Instrument Factory); somatotype microscope (Beijing Taike Instrument Co., Ltd.). METHODS: ① A total of 160 SD rats of half males and females were selected in this study. All rats were copulated. The day that the plug was checked out in the vagina next day was looked as the first day of pregnancy. Gravid rats were divided randomly into four groups, including early anesthesia group, second anesthesia group, late anesthesia group and control group with 20 in each group. Rats in the early anesthesia group were injected with 25 mg/kg soluble pentobarbitone on the 7th day of pregnancy for once; rats in the second anesthesia group were anesthetized with 25 mg/kg soluble pentobarbitone on the 7th and the 14th days of pregnancy for once; rats in the late anesthesia group were anesthetized with 25 mg/kg soluble pentobarbitone on the 14th day of pregnancy for once; rats in the control group did not treat with anything. The time of anesthetizing was controlled in 3 to 4 hours and ether was absorbed while the time was not enough. ② Half of each group was sacrificed on day 20th of pregnancy and the fetus was taken out to be stained with alizarin red S. After stained, the fetal skeleton was examined. The learning and memorizing of one-month rats that were given birth by the rest gravid rats were tested through electric mare method. Determine their study ability according to their correct rate of 90% or above of arrival at the safe area in 20 s. After they finally learned to arrive at the safe area correctly, test them once more in 24 hours and record the correct rate of 15 times. MAIN OUTCOME MEASURES: The rate of malformation in fetus and ability of learning and memory in one-month rats. RESULTS: A total of 80 female rats were anesthetized in this experiment. Totally 490 immature rats were tested with maze testing machine and 196 fetuses were stained with alizarin red S to observe the development of their skeleton. However, one of the 80 female rats was led to death because of overdose. ① Malformation experiment: Learning ability of second anesthesia group was evidently different from the control group while the other two groups were not in the electric mare method. The fetal skeleton malformation rate of three experimental groups was 87.0%, 60.9% and 17.9%, respectively, while it was 5.6% in the control group. ② Electric mare method: Times of rats which arrived at the safe regions were respectively 49.0±31.0, 68.0±35.0, 47.0±31.0 and 44.0±21.0 in early anesthesia group, second anesthesia group, late anesthesia group and control group; and then, there was significant difference between the second anesthesia group and the control group (P < 0.05). Exact rates of memory of rats were respectively (64.36±14.35)%, (62.15±18.33)%, (54.19±12.28)% and (68.24±15.91)% in early anesthesia group, second anesthesia group, late anesthesia group and control group; and then, there were no significant differences as compared with the control group (P > 0.05). CONCLUSION: The influence of anesthesia with pentobarbital sodium is obvious in fetal skeleton development and learning and memory ability. 展开更多
关键词 Embryonic skeleton development and neonatal learning and memory ability of rats anesthetized with pentobarbital sodium Differences of administration occasion and time
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Development and application of the ideological and political education in universities during new media time
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作者 Yinan Su Siqing Dong 《International Journal of Technology Management》 2014年第5期80-82,共3页
Science and technology proceed by leaps and bounds; our network is growing at an alarming rate which is reflected in the rapid development and popularization. Facing highly developed information technology, and the ra... Science and technology proceed by leaps and bounds; our network is growing at an alarming rate which is reflected in the rapid development and popularization. Facing highly developed information technology, and the rapid development of the network, strengthen ideological and political education is very important, the network has put impressive and comprehensive impact on the university teachers and students' lives, learning, work, moral, ideological and political attitudes, moral outlook, political literacy, life values, and ideological and political education in universities is facing a new challenge ; Meanwhile, the network also provides many new challenges and opportunities, expanding the channel and space of ideological and political education, it also can improve the quality of the main ideological and political education of high demand. Therefore, the educators of ideological and political education in colleges should keep up the pace of the rapid development of large- era, became not only who has a good ideological and political quality and comprehensive cultural knowledge quality, but also has very high literal ability and a solid information of network technology skills, so they could give full play to the advantages of information networks, do research and create a new situation in a large network of ideological and political education, then make the traditional ideological and political education produce a qualitative leap. 展开更多
关键词 development APPLICATION ideological and political education new media time
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MODEL-BASED DEVELOPMENT OF REAL-TIME SOFTWARE SYSTEM FOR ELECTRONIC UNIT PUMP SYSTEM 被引量:1
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作者 YU Shitao YANG Shiwei YANG Lin GONG Yuanming ZHUO Bin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第1期25-30,共6页
A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-base... A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-based task division method is introduced and the multi-task software architecture is built in the software system for electronic unit pump (EUP) system. The V-model software development process is used to control algorithm of each task. The simulation results of the hardware-in-the-loop simulation system (HILSS) and the engine experimental results show that the OS is an efficient real-time kernel, and can meet the real-time demands of EUP system; The built multi-task software system is real-time, determinate and reliable. V-model development is a good development process of control algorithms for EUP system, the control precision of control system can be ensured, and the development cycle and cost are also decreased. 展开更多
关键词 Real-time operating system (RTOS) Multi-task V-model development Hardware-in-the-loop simulation system(HILSS) Electronic unit pump (EUP)
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Using a support vector machine method to predict the development indices of very high water cut oilfields 被引量:13
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作者 Zhong Yihua Zhao Lei +2 位作者 Liu Zhibin Xu Yao Li Rong 《Petroleum Science》 SCIE CAS CSCD 2010年第3期379-384,共6页
Because the oilfields in eastern China are in the very high water cut development stage, accurate forecast of oilfield development indices is important for exploiting the oilfields efficiently. Regarding the problems ... Because the oilfields in eastern China are in the very high water cut development stage, accurate forecast of oilfield development indices is important for exploiting the oilfields efficiently. Regarding the problems of the small number of samples collected for oilfield development indices, a new support vector regression prediction method for development indices is proposed in this paper. This method uses the principle of functional simulation to determine the input-output of a support vector machine prediction system based on historical oilfield development data. It chooses the kernel function of the support vector machine by analyzing time series characteristics of the development index; trains and tests the support vector machine network with historical data to construct the support vector regression prediction model of oilfield development indices; and predicts the development index. The case study shows that the proposed method is feasible, and predicted development indices agree well with the development performance of very high water cut oilfields. 展开更多
关键词 Oilfield development indices oilfield performance support vector regression high watercut time series
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STUDY ON MICROWAVE DIELECTRIC PROPERTIES OF EPOXY RESIN MIXTURES USED FOR RAPID PRODUCT DEVELOPMENT 被引量:6
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作者 P.K.D. V. Yarlagadda (School of Mechanical, Manufacturing and Medical Engineering Queensland University of Technology (QUT) George Street, Brisbane, Qld 4001, Australia) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2001年第1期1-12,共12页
This paper presents a preliminary study on the dielectric properties and curing of three different types of epoxy resins mixed at various stoichiometric mixture of hardener, flydust and aluminium powder under microwav... This paper presents a preliminary study on the dielectric properties and curing of three different types of epoxy resins mixed at various stoichiometric mixture of hardener, flydust and aluminium powder under microwave energy. In this work, the curing process of thin layers of epoxy resins using microwave radiation was investigated as an alternative technique that can' be implemented to develop a new rapid product development technique. In this study it was observed that the curing time and temperature were a function of the percentage of hardener and fillers presence in the epoxy resins. Initially dielectric properties of epoxy resins with hardener were measured which was directly correlated to the curing process in order to understand the properties of cured specimen. Tensile tests were conducted on the three different types of epoxy resins with hardener and fillers. Modifying dielectric properties of the mixtures a significant decrease in curing time was observed. In order to study the microstructural changes of cured specimen the morphology of the fracture surface was carried out by using scanning electron microscopy. 展开更多
关键词 MICROWAVE curing time epoxy resin rapid product development
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Development Timing Assessment of Ecotourism Landscapes in Anhui Dawang Grotto Scenic Area of China
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作者 卢洁 万涛 沈慧芳 《Journal of Landscape Research》 2011年第5期70-73,共4页
Through analyzing 7 types of tourist resources in the Dawang Grotto Scenic Area(physiographic landscapes,waterscapes,biologic landscapes,historical remains,constructions and facilities,tourist products,human activitie... Through analyzing 7 types of tourist resources in the Dawang Grotto Scenic Area(physiographic landscapes,waterscapes,biologic landscapes,historical remains,constructions and facilities,tourist products,human activities),this study summarized the characteristics of this scenic area as "diversified physiographic landscapes,colorful rural life,beautiful waterscapes,picturesque mountain landscapes,rich biologic landscapes,and profound humanistic resources".On this basis,experience of other experts and research scientists were borrowed,classification system of ecotourism resources,AHP method,Delphi method and the comprehensive evaluation model of tourist site were applied,by classifying evaluation factors into 3 categories:resource value,ecological security and development condition,to categorize and divide the hierarchy of impact factors,determine the correlation among factors of different hierarchies and at different organization levels,and obtain weights of evaluation factors.Furthermore,development timing of ecotourism landscape resources in the Entrance Plaza Zone,Shengjing Lake Scenic Spot,Idyllic Scenic Spot,Shishen Youxian Scenic Spot,Dongfu Qiankun Scenic Spot was respectively evaluated.It was found that Dongfeng Qiankun Scenic Spot has better resources than others do,it has potentials to be developed into a first-class tourist site,but its ecological security and development condition should be further improved,and other four scenic spots need planning and development fit for their own characteristics. 展开更多
关键词 ECOTOURISM landscapes Evaluation development TIMING
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A Process-Based Model for Simulating Phasic Developmentand Phenology in Rice 被引量:3
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作者 MENG Ya-li, CAO Wei-xing, ZHOU Zhi-guo and LIU Xin-wei(Nanjing Agricultural University/Key Laboratory of Crop Growth Regulation, Ministry of Agriculture, Nanjing 210095 , P.R. China) 《Agricultural Sciences in China》 CAS CSCD 2003年第11期1277-1284,共8页
A simulation model for phasic and phenological development of rice was developed using the scale of physiological development time, based on the ecophysiological development processes. The interaction of daily thermal... A simulation model for phasic and phenological development of rice was developed using the scale of physiological development time, based on the ecophysiological development processes. The interaction of daily thermal effectiveness, photoperiod effectiveness and intrinsic earliness(before heading), and basic filling duration factor(after heading)determined the daily physiological effectiveness, which accumulated to get physiological development time. The Beta and quadratic functions were used to describe daily thermal and photoperiod effectiveness, respectively. Five specific genetic parameters were added to adjust the genotypic differences in rice development so that all different varieties could reach the same physiological development time at a given development stage. The stages of seedling emergence, panicle initiation, heading, and maturity were validated using sowing dates under different ecological environments, with the RMSE of 1. 47, 5. 10, 4.58 and 3.37 days, respectively. The results showed that the model was not only explanatory and systematic but also accurate and applicable. 展开更多
关键词 RICE Phasic development PHENOLOGY Physiological development time Simulation model PREDICTION
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Flower Development and Photoperiodic Control of Flowering in Rice 被引量:4
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作者 XIANG Chao QU Li-jun +1 位作者 GAO Yong-ming SHI Ying-yao 《Rice science》 SCIE 2013年第2期79-87,共9页
Floral transition,which is referred to as a plant's transition from vegetative stage to reproductive stage,is considered to be a critical developmental switch in higher plants,for a timely flowering is a major factor... Floral transition,which is referred to as a plant's transition from vegetative stage to reproductive stage,is considered to be a critical developmental switch in higher plants,for a timely flowering is a major factor of reproductive success.Endogenous and environmental cues,such as photoperiod,light quality,plant hormones concentrations and temperature,provide information to the plants whether the environment is favorable for flowering.These cues promote,or prevent,flowering through a complex genetic network,mediated by a careful orchestration of temporal and spatial gene expression.One of such cues is photoperiod.Rice(Oryza sativa L.) serves as a powerful model species for the understanding of flowering in higher plants,including flower development and photoperiodic control of flowering.In this review,we overviewed and discussed the flower development and its model.We also overviewed the photoperiodic pathways in rice flowering control,and summarized the pathways at molecular level. 展开更多
关键词 RICE flowering time gene floral transition flower development PHOTOPERIOD
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Ectopic expression of OsNF-YA8,an endosperm-specific nuclear factor Y transcription-factor gene,causes vegetative and reproductive development defects in rice 被引量:3
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作者 Baixiao Niu Jing Xu +3 位作者 Zhiguo E Zhenyu Zhang Xinming Lu Chen Chen 《The Crop Journal》 SCIE CSCD 2023年第6期1719-1730,共12页
Nuclear factor Y(NF-Y),a group of conserved transcription-factor complexes that consist of NF-YA,B,and C subunits,is essential for developmental regulation and for responses to environmental changes in eukaryotes.We p... Nuclear factor Y(NF-Y),a group of conserved transcription-factor complexes that consist of NF-YA,B,and C subunits,is essential for developmental regulation and for responses to environmental changes in eukaryotes.We previously found that some NF-Y genes,such as OsNF-YA8,were expressed specifically in the endosperm of rice.In the present study,overexpression of OsNF-YA8 in rice resulted in reduced plant height due to suppressed cell elongation in internodes.Gibberellin(GA)biosynthetic genes,including OsCPS1,OsGA20ox1,and OsGA20ox2,were down-regulated.OsNF-YA8 bound to the promoters of these genes to repress their expression.Endogenous GA content was decreased in OsNF-YA8 overexpressors,whose dwarf phenotype could be partially rescued by exogenous GA treatment.The findings suggested that ectopic expression of OsNF-YA8 causes defective GA biosynthesis in vegetative stage.Heading date in OsNF-YA8 overexpressors was delayed,especially under short-day conditions.OsNFYA8 bound to the promoter of Heading Date 3a(Hd3a),the florigen gene in rice,to negatively regulate flowering.Either ectopic activation or knockout of OsNF-YA8 impaired seed development,as indicated by reduced seed size and increased grain chalkiness.These results suggest that ectopic expression of the endosperm-specific OsNF-YA8 in rice disrupts both vegetative and reproductive development. 展开更多
关键词 RICE OsNF-YA8 Plant height Flowering time Seed development
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A pilot study, a specially designed pillow may prevent developmental plagiocephaly by reducing pressure from the infant head 被引量:1
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作者 Anna Ohman 《Health》 2013年第6期32-37,共6页
Developmental plagiocephaly (DP) has been an increasing problem since the successful “back to sleep campaign”. The referrals for DP have increased by >400% during the years 2004 to 2008. Many infants spend less t... Developmental plagiocephaly (DP) has been an increasing problem since the successful “back to sleep campaign”. The referrals for DP have increased by >400% during the years 2004 to 2008. Many infants spend less time in the prone position nowadays and some of the risk factors for DP are as follows: less than 3 times per day for the tummy time, torticollis and slow achievement of motor milestones. There is a need for better information to the parents but also for other strategies to prevent DP. The aim of this study was to investigate the effect of a special pillow and thus to reduce pressure on the infant head. Method: infants aged zero to two months were included in the study. They were randomized to either intervention group or control group. Head shape was investigated on two occasions, on the second occasion motor development, mobility and muscle function of the neck were also investigated. The parents were asked about tummy time and sleep position. All infants were investigated by the same physical therapist, blinded to group belonging. Result: seven infants had CVAI >3.5 on the last assessment, five of these had not used any method to reduce pressure. Fishers exact test showed a tendency where infants with reduced pressure on the head had less DP (P 0.08). Paired t test showed significant decrease in CVAI for the infants who had had reduced pressure on the head (P 0.01). Among these infants the CVAI was zero for 47% in the last assessment. For the infants who had not had a reduction of pressure on the head, there was no indication of a decrease of CVAI (P 0.45), and only 12% of these infants had a CVAI that was zero in the last assessment. Conclusion: this pilot study shows that a specially designed pillow may prevent DP in young infants. However, a larger sample is needed to confirm or disprove this. The study is planned to go on until there are 200 participants. 展开更多
关键词 developmentAL PLAGIOCEPHALY INFANT Pillow MOTOR development Tummy time
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