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Delineation of urban growth boundary based on FLUS model under the perspective of land use evaluation in hilly mountainous areas
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作者 ZHANG Yunping LIN Jianping +3 位作者 HUANG Yimin CHEN Zebin ZHU Chenhui YUAN Hao 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1647-1662,共16页
With rapid economic development,the size of urban land in China is expanding dramatically.The Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control ... With rapid economic development,the size of urban land in China is expanding dramatically.The Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control the urban sprawl.Reasonable delineation of UGB can inhibit the disorderly spread of urban space and guide the normal development of the city.It is of practical significance for the construction of green urban space.The study utilizes GIS technology to establish a land construction suitability evaluation system for Nankang city,which is experiencing rapid urban expansion,and outlines the preliminary UGB under the future land use simulation(FLUS)model.At the same time,considering the coupled coordination of"Production-Living-Ecological Space",and based on the suitability evaluation,we revised the preliminary UGB by combining the advantages of the patch-generating land use simulation(PLUS)model and the convex hull model to delineate the final UGB.The results show that:1)the comprehensive score of the evaluation of the suitability of the construction of land from high to low shows the distribution of the center of the city to the surrounding circle type spread,the center of the city has the highest suitability score.The results of convex hull model show that the urban expansion type of Nankang is epitaxial.In the future,the urban expansion will mainly occur in the northern part of the city.The PLUS model predicts an increase of 3359.97 hm^(2)of construction land in Nankang by 2035,of which 2022.97 hm^(2)is urban construction land.2)The FLUS model has a prediction accuracy of 86.3%and delineates a preliminary UGB area of 9215.07 hm^(2).3)We used the results of the construction suitability evaluation,PLUS model simulation results,and convex hull model predictions to revise the originally delineated UGB.The final delineated UGB area is 8895.67 hm^(2)and it is capable of meeting the future development of the study area.The results of the delineation can promote sustainable urban development,and the delineation methodology can provide a reference basis for the preparation of territorial spatial planning. 展开更多
关键词 Urban sprawl FLUS model Spatial correction Urban growth boundary Sustainable development
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Effects of Water-retaining Agents on Growth, Development, Yield and Quality of Soybean under Drought Stress
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作者 Hui XIA Yan ZHANG +2 位作者 Yun HAN Shasha HU Hengbin ZHANG 《Plant Diseases and Pests》 2024年第3期34-39,共6页
[Objectives]The paper was to explore the effects of different doses of water-retaining agent on the growth and development indicators,yield and quality of soybean plants subjected to drought stress.[Methods]The effect... [Objectives]The paper was to explore the effects of different doses of water-retaining agent on the growth and development indicators,yield and quality of soybean plants subjected to drought stress.[Methods]The effects of drought stress(MDS)and drought stress with low(MDS-L),medium(MDS-M)and high doses(MDS-H)of the water-retaining agent on the growth and development indicators,root activity,MDA content,antioxidant enzyme activity,yield and quality of soybean were studied by field plot test,with the normal water supply serving as the control(CK).[Results]In response to drought stress,the plant height,stem diameter,and yield of soybean exhibited a notable decline.Additionally,the contents of protein,fat,linoleic acid,and linolenic acid in seeds demonstrated a significant reduction.Conversely,the root activity and antioxidant enzyme activity exhibited a noticeable decline,while the MDA content exhibited an increase.The application of varying doses of the water-retaining agent was found to significantly enhance soybean growth,stimulate root activity,and elevate antioxidant enzyme activity,while concurrently reducing MDA content.The observed effects were found to be dose-dependent,with the greatest effects observed at the highest dose.In comparison to MDS,the yields of soybean in the MDS-L,MDS-M,and MDS-H treatments exhibited a 18.38%,25.58%,and 46.26%increase,respectively.Additionally,the content of protein,fat,linoleic acid,and linolenic acid in seeds demonstrated a notable enhancement.[Conclusions]The application of the water-retaining agent has been demonstrated to significantly promote the growth of soybean plants under conditions of drought stress,resulting in an improvement in both the yield and the quality of the soybean crop.The recommended dosage of the water-retaining agent is 3.3 kg/667 m 2. 展开更多
关键词 SOYBEAN Water-retaining agent YIELD Quality growth and development Antioxidant enzyme activity
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The Function of GABA in Plant Cell Growth, Development and Stress Response
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作者 Yue Jin Lulu Zhi +3 位作者 Xin Tang Yilin Chen John T.Hancock Xiangyang Hu 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第8期2211-2225,共15页
Gamma-aminobutyric acid(GABA)is a ubiquitous four-carbon non-protein amino acid that is involved in various physiological processes of plant growth and development,such as root architecture,stem elongation,leaf senesc... Gamma-aminobutyric acid(GABA)is a ubiquitous four-carbon non-protein amino acid that is involved in various physiological processes of plant growth and development,such as root architecture,stem elongation,leaf senescence,pollen tube growth,fruit ripening,and seed germination.GABA is also related to plant stress responses,such as drought,salt,cold,and heat stresses.Regulation of GABA in plant stress responses is complex and involves multiple signaling pathways,including calcium and hormone signaling.This paper systematically reviews the synthesis,metabolic pathways and regulatory role of GABA in plants,which will provide new insights into the understanding of plant growth and stress responses and offer novel strategies for improving crop productivity and stress. 展开更多
关键词 GABA STRESS growth and development
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Assessing the Contribution of Ecotourism to Economic Growth and Rural Development Offered by Wildlife Resources to People Living in Communities around Matusadonha National Park
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作者 Jesse Zvikonyaukwa Kudakwashe Musengi Clarice P Mudzengi 《Journal of Sustainable Business and Economics》 2023年第2期12-24,共13页
Ecotourism is one of the major drivers of economic growth and rural development in many countries involved in wildlife resource management.The objective was to assess the contribution of ecotourism to economic growth ... Ecotourism is one of the major drivers of economic growth and rural development in many countries involved in wildlife resource management.The objective was to assess the contribution of ecotourism to economic growth and rural development offered to people living in communities around Matusadonha National Park.A total of 140 participants were interviewed and questionnaires were administered to the same number of people.Data were analysed using both qualitative and quantitative methods.Results show that the majority of participants(57%)were females.Safari operations were the major(54.7%)ecotourism activity in Matusadonha National Park.Above half(58.8%)of participants indicated that ecotourism contributed toward economic growth in communities around Matusadonha National Park.Most people(343)were employed on a part-time basis from 2000 to 2022.Participants indicated that the standard of living in most communities increased by more than 50%.Above 50%of participants were satisfied with the contribution of ecotourism towards rural development.It can be concluded that ecotourism has the potential to improve economic growth and rural development if close monitoring and accountability of funds are monitored closely.Local people should be included in the accountability of funds and management of wildlife resources to improve economic benefits to local people. 展开更多
关键词 ECOTOURISM Wildlife resources Matusadonha National Park Economic growth Rural development
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SPATULA as a Versatile Tool in Plant:The Progress and Perspectives of SPATULA(SPT)Transcriptional Factor
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作者 Lei Liang Xiangyang Hu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期517-531,共15页
With the rapid development of modern molecular biology and bioinformatics,many studies have proved that transcription factors play an important role in regulating the growth and development of plants.SPATULA(SPT)belon... With the rapid development of modern molecular biology and bioinformatics,many studies have proved that transcription factors play an important role in regulating the growth and development of plants.SPATULA(SPT)belongs to the bHLH transcription family and participates in many processes of regulating plant growth and development.This review systemically summarizes the multiple roles of SPT in plant growth,development,and stress response,including seed germination,flowering,leaf size,carpel development,and root elongation,which is helpful for us to better understand the functions of SPT. 展开更多
关键词 SPT BHLH plant growth plant development Arabidopsis thaliana
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Plant growth and their root development after inoculation of arbuscular mycorrhizal fungi in coal mine subsided areas 被引量:19
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作者 Yinli Bi Yanxu Zhang Hui Zou 《International Journal of Coal Science & Technology》 EI 2018年第1期47-53,共7页
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Studies on hybridization effects of different geographic populations of Chlamys farreri Ⅱ.The medium-term growth and development of Chlamys farreri populations from China and Russia and their reciprocal crosses 被引量:12
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作者 LiuXiaolin ChangYaqing +3 位作者 XiangJianhai LiFuhua LiuXianjie BrovkinaElenaPavlovna 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第2期255-264,共10页
Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultura... Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultural population (CC) (?) × Russian population (RW) (?) , Chinese wild population (CW) (?) × Russian population (RW) (?), Russian population (RW) (?) × Chinese wild population (CW) (?) , the study of the medium-term (6, 8, 10, 12 months) growth and development of Chlamys farreri was carried out. The four determined results indicated that there existed different extent heterosis (3% -52%) for the growth in three types of F1 hybrids, and the offspring derived from CC(?) ×R(?) had a stronger heterosis among the crosses at the medium-term; the uptrend among traits are wet weight >shell width>shell length> shell height, Chinese cultural population could be recognized as excellent parent, and seasonal variations influence very much on the daily increment and growth rate of each trait of Chlamys farreri and it is only able to survive and could barely grow in winter (6-8 months), but grows fast in temperate season (10-12 months). 展开更多
关键词 Chlamys farreri POPULATION HYBRIDIZATION medium-term growth and development HETEROSIS
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Modified halloysite nanotubes reduce the toxic effects of zearalenone in gestating sows on growth and muscle development of their offsprings 被引量:3
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作者 Rui Gao Qingwei Meng +4 位作者 Jianan Li Min Liu Yuanyuan Zhang Chongpeng Bi Anshan Shan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2016年第4期570-578,共9页
Background: Zearalenone (ZEN) is an estrogenic mycotoxin that is primarily produced by Fusarium fungi and has been proven to affect the reproductive capacity of many species to varying degrees. The present experime... Background: Zearalenone (ZEN) is an estrogenic mycotoxin that is primarily produced by Fusarium fungi and has been proven to affect the reproductive capacity of many species to varying degrees. The present experiment was designed to study the maternal persistent effects of zearalenone toxicity in gestating sows on growth and muscle development of their offsprings, and the alleviation of zearalenone toxicity by modified halloysite nanotubes (MHNTs). Methods: Eighteen sows were fed with one of three dietary treatments that included the following: (1) a control diet, (2) a contaminated grain diet (with 50 % moldy corn, 2.77 mg/kg ZEN), and (3) a contaminated grain diet (with 50 % moldy corn, 2.76 mg/kg ZEN) + 1% MHNTs. Each sow was exclusively fed its experimental diets from 35 to 70 d of gestation at a total of 2 kg daily. Muscle samples were collected from six piglets per treatment at birth, weaning and finishing. Results: The results showed that feeding the sows with the ZEN-contaminated diets from 35 to 70 d of gestation decreased the ADG, ADFI and G:F of their offsprings (P 〈 0.05). The muscle fiber numbers in the newborn, weaning and growing-finishing pigs and the muscle fiber diameters at birth and weaning were also decreased by maternal ZEN exposure (P 〈 0.05). The expressions of IGF-I, IGF-II, Myf-5 and Mstn at birth and IGF-II, Pax7, Myf-5 and MyoD1 at weaning were altered by feeding gestating sows with ZEN-contaminated diets (P 〈 0.05). The MHNTs reduced most of the ZEN-induced toxic effects: the ADG and ADFI on growth performance, the muscle fiber numbers at weaning and finishing and the muscle fiber diameters at weaning (P 〈 0.05). The expression levels of IGF-II and Mstn in newborn piglets and IGF-II and Myf-5 in weaning piglets were also prevented by adding 1% MHNTs (P 〈 0.05). Conclusions: The present study demonstrated that the offsprings of sows fed with ZEN-contaminated diets from 35 to 70 day of gestation exhibited weakening on growth performance, physiological changes in their muscle fibers and alterations of mRNA expression in their muscle tissues, and also indicated that MHNTs prevented most of the ZEN- induced weakening in the muscle tissues. 展开更多
关键词 growth MHNTs Muscle development offsprings SOWS ZEARALENONE
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Influences of the Populus deltoids seedlings treated with exogenous methyl jasmonate on the growth and development of Lymantria dispar larvae 被引量:2
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作者 HU Zeng-hui ZHAO Ling +2 位作者 YANG Di SHEN Ying-bai SHEN Fan-yi 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期277-280,共4页
Lyantria dispar larvae were fed with the leaves of Populus deltoids seedlings exposed to methyl jasmonate (MeJA) for 24 h. The growth and development of the larvae were investigated, and phenolics contents in treate... Lyantria dispar larvae were fed with the leaves of Populus deltoids seedlings exposed to methyl jasmonate (MeJA) for 24 h. The growth and development of the larvae were investigated, and phenolics contents in treated leaves including pyrocatechol, caffeic acid, coumarin, fernlic acid and benzoic acid were also surveyed by high-pressure liquid chromatography (HPLC). Results indicated that approximate digestibility, efficiency of conversion of ingested food, efficiency of conversion of digested food, and weight of the larvae were inhibited obviously, especially from the sixth day, which may result from the increase of total phenolics contents in treated leaves. This result provides strong supports for MeJA acting as the airborne signal molecule between woody plants. 展开更多
关键词 Interplant communication Defense response in Populus deltoids plants Exogenous MeJA growth and development of lymantria dispar Phenolics contents
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Thailand's economic growth and structural development projections in the context of environmental control 被引量:1
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作者 Sompote Kunnoot 《Chinese Journal of Population,Resources and Environment》 2015年第3期272-280,共9页
Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium(CGE) model to compare the following four scenarios:(1) stand... Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium(CGE) model to compare the following four scenarios:(1) standard growth with infinite supply of factors,(2) finite land supply,(3) fixed use of agricultural chemicals,and(4) combined finite land supply with fixed use of agricultural chemicals.The computable projections suggest that the economic cost of hypothetical environmental control in agriculture is small and further weakened by urbanization.The computed structural development points to efficiency improvements specific to sectors to return the economy to balanced growth. 展开更多
关键词 STRUCTURAL development ENVIRONMENTAL control ECONOMIC growth PROJECTION
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Effects of NaCl stress on the biochemical substances in Bt cotton as well as on the growth and development and adult oviposition selectivity of Helicoverpa armigera 被引量:2
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作者 LUO Junyu ZHANG Shuai +6 位作者 ZHU Xiangzhen JI Jichao ZHANG Kaixin WANG Chunyi ZHANG Lijuan WANG Li CUI Jinlie 《Journal of Cotton Research》 2019年第1期17-25,共9页
Background:Recently,due to the development of food security strategies,cotton has been planted in inland saline-alkali dry soils or in coastal some saline-alkali soils in China.Under the condition,to comprehensively p... Background:Recently,due to the development of food security strategies,cotton has been planted in inland saline-alkali dry soils or in coastal some saline-alkali soils in China.Under the condition,to comprehensively prevent and control Helicoverpa armigera in cotton fields with saline-alkali soils,it is important to study the larval growth and development of H.armigero and to study adult oviposition selectivity in H.armigera adults that feed on NaCI-stNaCled cotton plants.Results:In this study,Bt cotton GK19 was used for the experimental group and its nontransgenic parent Simian 3 was used for the control to study the effects of biochemical substances in cotton as well as larval growth and development and adult oviposition selectivity of H.armigera.The experiments were performed by growing cotton indoors under NaCl stress at concentrations of 0 mmol-L-1,75 mmol-L-1 and 150 mmol-L-1,respectively.The results showed that the expression of Bt protein was significantly inhibited for NaCI-stressed Bt cotNaClThe content of soluble protein and K+ in the leaves of cotton were decreased,while the content of gossypol and Na+were increased.In addition,the 5th instar H.armigera larvae exhibited shorten the life span in a 13-day trial period.Under enclosure treatments and at different female densities,the adult oviposition of H.armigera decreased on high NaCI-stressed nontransgenic coNaCl,while the oviposition on Bt cotton tended to first increase but then decrease under low,moderate and high NaCl stress treatments.Conclusions:Under certain content ranges of NaCl stress treatments,larval of H.armigera growth and development,and adult oviposition were no significant difference in the change for a certain period.However,under high NaCl stress,larval growth,development and adult oviposition were affected,which may provide insights for the prevention and control of H.armigero for Bt cotton in saline-alkali soils. 展开更多
关键词 NaCl stress Bt cotton BIOCHEMICAL substance HELICOVERPA ARMIGERA growth and development OVIPOSITION selectivity
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Functions of Nitrogen,Phosphorus and Potassium in Energy Status and Their Influences on Rice Growth and Development 被引量:1
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作者 MA Jiaying CHEN Tingting +8 位作者 LIN Jie FU Weimeng FENG Baohua LI Guangyan LI Hubo LI Juncai WU Zhihai TAO Longxing FU Guanfu 《Rice science》 SCIE CSCD 2022年第2期166-178,共13页
Nitrogen(N),phosphorus(P)and potassium(K)are important essential nutrients for plant growth and development,but their functions in energy status remains unclear.Here,we grew Nipponbare rice seedlings in a growth chamb... Nitrogen(N),phosphorus(P)and potassium(K)are important essential nutrients for plant growth and development,but their functions in energy status remains unclear.Here,we grew Nipponbare rice seedlings in a growth chamber for 20 d at 30℃/24℃day/night)under natural sunlight conditions with different nutrient regimes.The results showed that N had the strongest influence on the plant growth and development,followed by P and K.The highest nonstructural carbohydrate content,dry matter weight,net photosynthetic rate(Pn),ATP content,as well as NADH dehydrogenase,cytochrome oxidase and ATPase activities were found in the plants that received sufficient N,P and K.The lowest values of these parameters were detected in the N-deficient plants.Higher dry matter accumulation was observed in the K-deficient than in the P-deficient treatments,but there was no significant difference in the ratio of respiration rate to Pn between these two treatments,suggesting that differences in energy production efficiency may have accounted for this result.This hypothesis was confirmed by higher ATP contents and activities of NADH dehydrogenase,cytochrome oxidase and ATPase in the K-deficient plants than in the P-deficient plants.We therefore inferred different abilities in energy production efficiency among N,P and K in rice seedlings,which determined rice plant growth and development. 展开更多
关键词 RICE nutrient element PHOTOSYNtheSIS RESPIRATION plant growth and development energy production efficiency
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Advances in Studies of the Effects of Starvation on Growth and Development of Fish Larvae 被引量:2
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作者 SHAN Xiujuan HUANG Wei +1 位作者 CAO Liang WU Yunfei 《Journal of Ocean University of China》 SCIE CAS 2008年第3期319-326,共8页
Starvation has important effects on early development of fish. It determines the survival and growth of fish larvae,and plays an important role in the dynamics of fish population and fisheries recruitment. In this rev... Starvation has important effects on early development of fish. It determines the survival and growth of fish larvae,and plays an important role in the dynamics of fish population and fisheries recruitment. In this review,we discuss the current studies about the effects of starvation on growth and development of fish larval stage. The goals of this review are to understand some adaptive mechanisms and ecological countermeasures of starved fish larvae and to provide the scientific guideline for exploring early life history processes,evaluating the nutrition condition and growth of larval fish,protecting fish resource and breeding fish larvae. 展开更多
关键词 稚鱼 发育过程 饥饿现象 饲养技术
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The influence of Fe^(2+) on growth and development of cells enzy-matically isolated from Porphyra yezoensis blades 被引量:2
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作者 沈颂东 戴继勋 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第1期48-53,共6页
Fe2+ acted as an accessorial factor for many cellular enzymatic reactions is very important for seaweed growth and development, but the Fe2+ requirement in nori had not been seen. Porphyra yezoensis cells were separat... Fe2+ acted as an accessorial factor for many cellular enzymatic reactions is very important for seaweed growth and development, but the Fe2+ requirement in nori had not been seen. Porphyra yezoensis cells were separated enzymatically and cultured in a series of sterilized seawater media containing various concentra- tions of Fe2+. The growth development and cell were investigated in this work. Through this experiment, two biologically-meant concentration scales were found, one is low concentrations, 12.1–102.1 μg/L, 10–100 times than that in seawater, favoring the development of isolated cells of Porphyra and the other was high concentra- tions, more than 10mg/L inhibiting the cell growth, leading to the deformity and shrinkage of the cells. At the concentration of 50 mg/L, the cells stopped growing and died eventually. 展开更多
关键词 FE^2+ 海水 分离工艺 海洋化学
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Effect of Electromagnetic Radiation on the Growth and Development of Euproctis pseudoconspersa Strand
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作者 Chunjiang SHUAI 《Agricultural Biotechnology》 CAS 2019年第2期124-127,132,共5页
The principal component method is to recombine multiple correlated indexes into a group of non-correlated comprehensive indexes to replace the original indexes for evaluation. The paper took the test data of growth an... The principal component method is to recombine multiple correlated indexes into a group of non-correlated comprehensive indexes to replace the original indexes for evaluation. The paper took the test data of growth and development of Euproctis pseudoconspersa Strand as a basis and used the principal component analysis method to analyze and investigate the test data. The research results indicate that the principal component analysis method is a model with actual operation value and evaluation reliability. When the electromagnetic radiation is higher than 100 K, the growth and development indexes of E. pseudoconspersa Strand are correlated to electromagnetic radiation frequency to some extent. 展开更多
关键词 ELECTROMAGNETIC RADIATION Euproctis pseudoconspersa STRand growth and development
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Evaluation of Impact of Pollen Grains from Bt,Bt/CpTITransgenic Cotton and Bt Corn Plants on the Growth andDevelopment of the Mulberry Silkworm,Bombyx moriLinnaeus (Lepidoptera:Bombycidae)
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作者 LI Wen-dong, YE Gong-yin, WU Kong-ming, WANG Xiao-qi and GUO Yu-yuan(Institute of Plant Protection , Chinese Academy of Agricultural Sciences , Beijing 100094 , P. R. China College ofPlant Protection, Shenyang Agricultural University, Shenyang 110161 , P.R.China Institute of AppliedEntomology, Zhejiang University , Hangzhou 310029 , P.R.China) 《Agricultural Sciences in China》 CAS CSCD 2002年第12期1334-1343,共10页
The S-endotoxin genes of Bacillus thuringiensis (Bt) and proteinase inhibitor (PI) genes are two kinds of genes popularly used for developing transgenic plants resistant to insect pests. To clarify whether there is an... The S-endotoxin genes of Bacillus thuringiensis (Bt) and proteinase inhibitor (PI) genes are two kinds of genes popularly used for developing transgenic plants resistant to insect pests. To clarify whether there is any risk concerning the effects of pollens from these transgenic crops on non-target insects with economic importance, such as the effects on the growth and development as well as cocoon quality of the silkworm, Bombyx mori Linnaeus, a series of feeding experiments were conducted, using pollens from transgenic cotton or corn containing cry 1Ac, cry1A+CpTI or crylAb genes, compared with pollens from non-transgenic normal cotton and corn as well as the non-pollen treatment. In contrast to the latter ones, pollens from transgenic plants showed no significant adverse effects on larval mortality, cocoon weight, pupa weight, cocoon shell weight, pupation rate, emergence rate and fecundity of the silkworm after neonates were fed with the pollens for 72 h. In addition, no dosage effects of pollens were found. Though the duration of 1st instar larvae was prolonged in the case of feeding with transgenic pollens as compared with those of the non-pollen treatment , but they were not significantly different from those fed with pollens from non-transgenic cotton or corn. Meanwhile, the body weight of the 3rd instar molters fed with transgenic pollens was obviously different from those for non-pollen treatment, and was all significantly heavier than that of the controls. Consequently, it is considered that the adverse effect of pollens from transgenic insect-resistant cotton and corn on the growth and development of the silkworm is negligible. 展开更多
关键词 Bt/CpTI transgenic cotton Bt transgenic corn POLLEN Bombyx mori growth and development
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Changes in embryonic development,juvenile growth and physiological adaptation of the cuttlefish Sepia pharaonis in response to photoperiod manipulation
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作者 Maowang JIANG Huan CHEN +3 位作者 Shuangnan ZHOU Qingxi HAN Ruibing PENG Xiamin JIANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第5期2012-2027,共16页
Photoperiod is a key environmental indicator for re gulating embryonic development,individual growth and physiological processes in aquatic animals.In this study,differences in embryonic development and performance of... Photoperiod is a key environmental indicator for re gulating embryonic development,individual growth and physiological processes in aquatic animals.In this study,differences in embryonic development and performance of newly hatched cuttlefish juvenile exposed to five different cycles of light:dark(L:D):constant light,18 L:6D,12 L:12D,6 L:18D cycles,and constant darkness were evaluated.Prolonged exposure to light induced an accelerated rate of embryonic development,particularly after the red-bead stage.Principal component analysis(PCA)revealed that red-bead stage,heartbeat,endoskeleton formation,pigment appear,and six increments of cuttlebone were the main factors contributing to the embryonic development.Meaning that the duration time of these five stages were significantly different when exposed to photoperiod regimes,which may determine the duration of the incubation period of the embryos.Long term light has also affected the incubation parameters with an increased rate in hatching and shortened the incubation and hatching periods in the 12-24-h day length range.However,constant light and darkness environment appeared to have a greater effect on the stress of embryonic development,mainly reflected in the yolk shed ratio and the inking rate in the egg capsule.Moreover,the increase in the day length has contributed to improve the growth and survival of juveniles in the 12-18-h day length range;however,juveniles exposed to constant light and darkness experienced worse re sults in terms of growth,tissue glycogen content,dige stive enzymes of the digestive glands,and metabolic enzymes of the muscles.These finding suggest that prolonged light exposure accelerates the process of embryonic development,maximum feeding time is not necessarily a condition of optimal growth,and inappropriate light cycles can disturb the body’s endogenous controls.Therefore,the optimal photoperiod for the embryos development and juvenile growth of Sepia pharaonis were 12 h and 12-18 h of day length,respectively.These results are useful for increasing the production of this species during embryo incubation and juveniles rearing in aquaculture practice. 展开更多
关键词 PHOTOPERIOD embryonic development growth physiological changes CUTTLEFISH
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The Impact of Ecologic Factors on Growth and Development of Two Polygonatum Species
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作者 Saidahmat A. Omarov 《American Journal of Plant Sciences》 2019年第5期730-737,共8页
The research results of environment impact on growth and development of Polygonatum odoratum (Mill.) Druce and Polygonatum severtzowii Regel species are given in the article. The effect of light intensity, temperature... The research results of environment impact on growth and development of Polygonatum odoratum (Mill.) Druce and Polygonatum severtzowii Regel species are given in the article. The effect of light intensity, temperature and humidity factors was noted in the studied species. 展开更多
关键词 POLYGONATUM odoratum (Mill.) Druce POLYGONATUM severtzowii Regel growth development Environment FACTORS Tashkent BOTANICAL GARDEN
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The Disputes over "Normal Development" and "Natural Growth" of Farmers' Cooperatives——On the Basis of Empirical Analysis on Farmers' Cooperatives in Deyang City
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作者 CHAI Xu-xu QIN Zi-qiang +1 位作者 LIU Wen GUO Liu-xian 《Asian Agricultural Research》 2011年第6期101-104,共4页
Combining the disputes on the "normal development" and "natural growth" existing in farmers' cooperatives and according to the actual investigation statistics, the management model selection an... Combining the disputes on the "normal development" and "natural growth" existing in farmers' cooperatives and according to the actual investigation statistics, the management model selection and regulation (including model selection, policy encouragement, operation scale and scale selection ) of farmers'cooperatives in Deyang City, share structure and governance structure( including the establishment way and share structure, reserve sharing and dividend distribution, organization structure and policy-making mechanism), capital raising situation and financial support of farmers' cooperatives in Deyang City are analyzed empirically. It is pointed out the farmers' cooperatives should take the road "normal development". 展开更多
关键词 Farmers’cooperatives Normal development Natural growth China
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An Inquiry into the Relationship between Population Growth and Development:The Case of Malawi and Kenya
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作者 Simon Kipronoh Ruttoh Milward Tobias +1 位作者 Benard Kipngeno Ruttoh Ernest Kiplangat Kirui 《Journal of Environmental Science and Engineering(A)》 2018年第10期424-429,共6页
This paper sought to analyze the relationship between population growth and development. The motivation is that population growth has been blamed as a cause of being under development in LDS (Least Developed Countries... This paper sought to analyze the relationship between population growth and development. The motivation is that population growth has been blamed as a cause of being under development in LDS (Least Developed Countries). This is a descriptive study employing review of secondary data and reports. There is no direct relationship between population growth and being under development. This is supported by countries which are populous yet their economies are growing fast enabling them to graduate from developing and donor reliant to developed and donating countries. China and India are examples. Again, data show that socio-economic indicators were not any better when population sizes were low in the last 3 to 4 decades. Countries should focus on sound economic management to improve the supply side of goods and services which ultimately will result in reduced population growth as one of the effects. It is concluded that the notion of high population is built on the experienced and anticipated challenges in supplying goods and services that meet the demand and not on any standard measure as to what is standard population size for a country of a given physical size and natural resources. 展开更多
关键词 POPULATION development PER capita growth GDP (Gross DOMESTIC Product)
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