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Correlation of personality with individual reproductive success in shrub-nesting birds depends on their life history style
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作者 Jianchuan Li Wen Zhang +5 位作者 Ningning Sun Yujie Wang Lifang Gao Ran Feng Liqing Fan Bo Du 《Avian Research》 SCIE CSCD 2024年第1期42-49,共8页
Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain ... Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain unresolved.We addressed these two questions in three shrub-nesting birds,the Azure-winged Magpie(Cyanopica cyanus,AM),White-collared Blackbird(Turdus albocinctus,WB),and Brown-cheeked Laughingthrush(Trochalopteron henrici,BL).The personality type of an individual was first identified according to its response to a territorial intruder.Then,we compared the fleeing distance,breeding parameters,and differential expressed genes(DEGs) in the brain transcriptome between bold and shy breeders.In the three species,bold breeders exhibited more aggressiveness towards an intruder of their territory than did shy breeders.The reproductive success of bold breeders was significantly higher than that of shy breeders in AM but not in WB and BL.The three species shared one DEG,crabp1,which was up-regulated in bold relative to in shy individuals.By regulating the expression of corticotropin-releasing hormone,higher crabp1 gene expression can decrease cellular response to retinoic acid.Therefore,bold individuals are insensitive to external stresses and able to exhibit more aggressiveness to intruders than their shier counterparts.Aggressiveness is beneficial to bold individuals in AM but not in WB and BL because the former could evoke neighbors to make the same response of defending against intruders but the latter could not.Although a personality trait may have the same genetic basis across species,its correlation with reproductive success depends largely on the life history style of a species. 展开更多
关键词 BOLDNESS life history style PERSONALITY Reproductive success Transcriptome analysis
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Degradation and resynthesis of chlorophyll during increased oxidative stress and prolonged darkness differ between annual and perennial flax(Linum L.)
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作者 Kenyon J. Nisbett Abida Alokozai +2 位作者 Su Hyun Elizabeth Ko G. Adam Mott Jason C.L. Browna 《Oil Crop Science》 CSCD 2024年第2期121-130,共10页
Among plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the longest-living perennial having survived 43,600 years.As proposed by the Disp... Among plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the longest-living perennial having survived 43,600 years.As proposed by the Disposable Soma Theory,this lifespan variation among plants likely reflects differential investment of limited energy and nutrient resources,with perennials investing more energy and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple seasons.Such differential investment may be particularly important during periods of exogenous stress,which are known to accelerate biomolecular damage.The present study evaluated this hypothesis using annual and perennial flax(Linum L.)subjected to two exogenous stressors—increased oxidative stress(i.e.,foliar H2O2spraying)and complete prolonged darkness.As chlorophyll has been shown to exhibit degradation in response to changes in environmental conditions,we utilized changes in chlorophyll levels during and after periods of exogenous stress to evaluate our hypotheses.We predicted that i)perennials would exhibit a slower rate of chlorophyll degradation during exposure to exogenous stressors compared to annuals,and ii)perennials would exhibit a faster rate of chlorophyll resynthesis following such exposure compared to annuals.Chlorophyll levels before,during,and after exposure to both exogenous stressors were measured in two separate trails,once using image colour analysis and once using spectrophotometry.While chlorophyll degradation rates in response to oxidative stress did not differ between annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates following such exposure were significantly higher in perennials,as predicted.When plants were subjected to complete prolonged darkness,chlorophyll degradation rates were significantly lower in perennials than annuals,as predicted;however,when plants were subsequently reintroduced to natural photoperiod,chlorophyll resynthesis rates did not consistently differ between annuals and perennials,though they tended to be higher in the latter,as predicted.Overall,our study illuminates that evolutionary transitions between life history strategies in plants have been accompanied by physiological modifications to chlorophyll dynamics that permit perennial species to better maintain chlorophyll levels—and thus photosynthetic energy acquisition-in the face of exogenous stressors,which likely underlies their capacity to survive for multiple growing seasons.Future studies should explore whether other key biomolecules(e.g.,proteins,DNA)are also better maintained in perennial plants,especially in the face of exogenous stress. 展开更多
关键词 Ageing life history Maximum lifespan Oxidative stress Somatic maintenance
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A preliminary study on life history of marine red alga Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li
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作者 Bingxin HUANG Yao ZHANG +4 位作者 Yue CHU Youxuan GUO Junxia LIANG Jianan QIN Lanping DING 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期915-922,共8页
Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li is a common species in the genus Stylonema,but there are limited reports on morphological taxonomy and a lack of studies on life history and the regulation of ea... Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li is a common species in the genus Stylonema,but there are limited reports on morphological taxonomy and a lack of studies on life history and the regulation of early development.The early development,discoid formation,and erect thallus growth of Stylonema alsidii f.ramosum were observed under laboratory conditions.In addition,the influence of main environmental factors such as temperature and light intensity on its development was briefly studied,and various stages of its life history were observed.The result shows:(1)there are two reproductive modes:asexual reproduction and sexual reproduction;(2)the morphology of this species varies in different degrees under laboratory culture conditions;(3)sexual reproduction and asexual reproduction can coexist under suitable conditions.Five pathways of life history were inferred from experimental phenomena.Mature sporophytes form mature gametophytes by producing initially isolated or initially attached monospore,and mature gametophytes form mature sporophytes by fertilization of eggs and sperms.The sexual and asexual reproduction processes of Stylonema alsidii f.ramosum were reported for the first time,and this is also the first report on sexual reproduction in the genus Stylonema. 展开更多
关键词 Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li life history environmental factor asexual reproduction sexual reproduction
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Temperature Effect on the Life History of Three Types of Brachionus calyciflorus Females 被引量:4
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作者 席贻龙 黄祥飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第2期192-197,共6页
The effect of temperature on the life history characteristics of amictic females (AF), unfertilized mictic females (UMF) and fertilized mictic females (FMF) in Brachionus calyciflorus was studied with replicated indiv... The effect of temperature on the life history characteristics of amictic females (AF), unfertilized mictic females (UMF) and fertilized mictic females (FMF) in Brachionus calyciflorus was studied with replicated individual cultures at 20℃,25℃ and 30℃, and with algae Scenedesmus obliquus for their food. There were highly significant effects of both temperature and female type, independently and interactively, on the duration of juvenile and post-reproduction periods, and the number of eggs produced by the rotifer per life cycle. Among all the temperature-female type combinations, all the juvenile periods of FMF, and the post-reproduction periods of UMF and FMF at 20℃, were the longest, and the number of eggs produced by an UMF at 30℃ was the highest. There were highly significant effects of both temperature and female type on the duration of the reproduction period, but no clear correlation was observed between temperature and female type. The reproduction period of AF was longer than that of UMF and FMF. Only temperature influenced significantly the mean life-span of the three types of females. The duration of juvenile, reproduction and post-reproduction periods as well as the life-span of the three types of females were all reduced very significantly with rise of temperature, but the rates of reduction varied with female type. Among the three types of females, the number of eggs produced per life cycle by an UMF was the highest, and that of a FMF was the lowest. A significant relationship between the number of eggs produced per life cycle and temperature was observed only in the UMF. 展开更多
关键词 融合生殖 雌性 单体 有交织字母轮虫 循环
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Opportunistic-tended life history traits of Siniperca kneri in the Three Gorges Reservoir,China: potential responses to impoundment
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作者 ZHAO Shasha CHENG Fei +2 位作者 HOU Gang HU Zhengyu XIE Songguang 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第2期694-705,共12页
Reservoir impoundment changes original fluvial habitats into lentic environments. Fish species adapted to lentic habitats may take the advantage of such habitat changes and show typical life history traits might facil... Reservoir impoundment changes original fluvial habitats into lentic environments. Fish species adapted to lentic habitats may take the advantage of such habitat changes and show typical life history traits might facilitate the population increase. Siniperca kneri rarely occurred in fishery landing in the Three Gorges Reservoir (TGR) area before its impoundment in 2003, but it is now a dominant species. In this study, a total of 438 females of S . kneri were collected monthly during September 2012 through January 2014 using gill nets in the TGR. The age, growth, and reproductive biology were then investigated, and compared with other S . kneri populations. The standard length at age 1 was 149.9 mm in the TGR, which is larger than the three compared populations (i.e., Sandaohe Reservoir, Xinfengjiang Reservoir, and North River), but smaller than one (the Guishi Reservoir). The youngest mature female in the TGR was age 1, which is younger than that of the two compared populations (i.e., Xinfengjiang Reservoir and the North River). The relative fecundity in the TGR was 140 eggs/g, which is higher than that of the only available compared population (Xinfengjiang Reservoir, 96 eggs/g). Our results demonstrated that S . kneri in the TGR tended to have faster growth in the first year, a younger age at first maturation, and higher reproductive eff ort. We suggest that such opportunistic-tended life history traits might facilitate rapid increase of the population. 展开更多
关键词 SINIPERCA kneri life history TRAITS OPPORTUNISTIC growth REPRODUCTION COLONIZATION
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Life Cycle-Stages in History of Tourism in the Republic of Macedonia
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作者 Nikola V. Dimitrov 《Journal of Tourism and Hospitality Management》 2017年第5期173-188,共16页
关键词 life cycle TALC model history of TOURISM regulation theories FORD PARADIGM MACEDONIA
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Effects of life-history components on population dynamics of the rare endangered plant <i>Davidia involucrata</i> 被引量:1
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作者 Haimei You Yanhong Liu Kazue Fujiwara 《Natural Science》 2013年第1期62-70,共9页
In order to estimate the most effect stage and process on population growth and effective conserve the rare endangered plant Davidia involucrata, we analyzed the dynamics and the contributions of life-history componen... In order to estimate the most effect stage and process on population growth and effective conserve the rare endangered plant Davidia involucrata, we analyzed the dynamics and the contributions of life-history components on population dynamics based on Lefkovitch matrix model and sensitivity analysis. The life cycle of Davidia involucrata was divided into six stages (seed, seedling, juvenile, immature, early adult and late adult) based on the species characteristics and published literature data, the survival rates in each life-history stage were simulated using a static life table, and the fecundity of each stage was determined according to sample information. The results showed that the structure of the observed population was not ideal, and the numbers of seedlings and coppice shoots was similar. The population growth rate was influenced largely by individual growth process, and asexual reproduction made a larger contribution to population growth than sexual reproduction. However, sexual reproduction was more important than asexual reproduction, because most asexual reproducing individuals (the coppice shoots) were derived mainly from human destruction (e.g. felling trees). The most important stage was stage V (late adult), associated with seed production and germination. Therefore, conservation of Davidia involucrata populations should focus on stage V and sexual reproduction, in order to improve the seed production and germination rate, and to promote population stability and development. 展开更多
关键词 Davidia INVOLUCRATA Lefkovitch Matrix model life-history Stage Population ECOLOGY Sensitivity Analysis
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An Insight Into the Promise and Problems of Combining Life History and Grounded Theory Research
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作者 Bronwyn Betts 《Chinese Business Review》 2013年第2期84-92,共9页
关键词 生活史 教育工作者 终身学习 哲学方法 相互作用 经验数据 工作界面 现象学
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Covariation in Insular Life-history Traits of the Rice Frog(Fejervarya limnocharis)in Eastern China
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作者 Feng XU Gregory H.ADLER Yiming LI 《Asian Herpetological Research》 SCIE 2013年第1期28-35,共8页
Although shifts in life-history traits of insular vertebrates, as compared with mainland populations, have been observed in many taxa, few studies have examined the relationships among individual life-history traits o... Although shifts in life-history traits of insular vertebrates, as compared with mainland populations, have been observed in many taxa, few studies have examined the relationships among individual life-history traits on islands. Lifehistory theory also predicts that there is a trade-off between body size and reproductive effort, and between egg size and clutch size. We surveyed the rice frog, Fejervarya limnocharis, on 20 islands within the Zhoushan Archipelago and two nearby sites on the mainland of China to compare differences in life-history traits and to explore relationships among those traits. Rice frog females reached a greater body size on half of the smaller islands among the total 20 surveyed islands, and larger egg size, decreased clutch size and reduced reproductive effort on most of the islands when compared to the two mainland sites. Insular body size was negatively correlated with reproductive effort. There was a negative correlation between egg size and clutch size. Results suggest that life-history theory provides a good explanation for co-variation between body size and reproductive effort, and between egg size and clutch size in rice frogs on the islands. 展开更多
关键词 island syndrome life-history traits trade-off body size egg size clutch size reproductive effort
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Simulation of the distribution,growth,and survival rate of chub mackerel larvae and juveniles in the East China Sea 被引量:1
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作者 Wenjiang GUAN Xuelian MA +1 位作者 Weiwei HE Ruixing CAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1602-1619,共18页
In the East China Sea(ECS),chub mackerel Scomber japonicus constitutes an important coastal-pelagic fishery resource that is mainly exploited by Chinese,Japanese,and Korean light-purse seine fisheries.Because the earl... In the East China Sea(ECS),chub mackerel Scomber japonicus constitutes an important coastal-pelagic fishery resource that is mainly exploited by Chinese,Japanese,and Korean light-purse seine fisheries.Because the early life history of chub mackerel plays a significant role in its recruitment,we developed an individual-based model to study the distribution,growth,and survival rate of chub mackerel larvae and juveniles in the ECS to improve our understanding of the chub mackerel population structure and recruitment.Our results show that as body length rapidly increases,the swimming capacity of chub mackerel larvae and juveniles improves quickly,and their spatial distribution depends more on their habitat conditions than the ocean currents.Correspondingly,the juveniles from the central and southern ECS spawning ground are scarcely recruited into the Japan/East Sea(JES)or the western Pacific Ocean,but a significant proportion of juveniles from the northern ECS spawning ground still enter the JES and there are exchanges between the stocks in the ECS and JES.Thus,it seems more reasonable to assess and manage the chub mackerels in the ECS and JES as a stock.The water temperature and ocean primary production in the ECS are two important factors influencing the chub mackerel habitat conditions and their spatial and temporal distribution are significantly different as the spawning time changes.Therefore,the spawning time and location play an important role in the growth and survival rate of the larvae and juveniles.Generally,when chub mackerel spawns at the southern ECS spawning ground in March,the larva and juvenile growth and survival rate is relatively high;as spawning time moves forward,higher growth and survival rates would be expected for the chub mackerel spawned coastward or northward.For specific spawning sites,early or delayed spawning will reduce the survival rate. 展开更多
关键词 East China Sea(ECS) Scomber japonicus individual-based model early life history
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The history of interventional therapy for liver cancer in China 被引量:62
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作者 Mengxuan Zuo Jinhua Huang 《Journal of Interventional Medicine》 2018年第2期70-76,共7页
In China interventional therapy of liver cancer started in the 1980s. It is well-known that Professor Lin Gui is the founding father of Interventional radiology. Under the leadership of Lin Gui and other professors, i... In China interventional therapy of liver cancer started in the 1980s. It is well-known that Professor Lin Gui is the founding father of Interventional radiology. Under the leadership of Lin Gui and other professors, interventional therapy of liver cancer has swiftly progressed in China. Indeed, TAI, TAE, TACE and ablation therapy have witnessed great innovations in hardware facil ities, technical means, and therapeutic philosophy, while incorporating Chinese characteristics. As with the development of combined interventional therapy in China, interventional treatment of liver cancer has gradually started the process of precision and individualization. Actually, multidisciplinary, multimodal, and polymorphic treatments will be the most suitable pattern for liver cancer in the future, among which combination of interventional therapy with targeted, immunological treatments and information technology(IT) tools may bring a revolutionary breakthrough in liver cancer treatment. 展开更多
关键词 LIVER cancer history INTERVENTIONAL therapy EMBOLIZATION ablation MULTI-MODAL individualized treatment
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Study on fish life history traits and variation in the Taiwan Strait and its adjacent waters 被引量:3
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作者 HU Wenjia YE Guanqiong +4 位作者 LU Zhenbin DU Jianguo CHEN Mingru CHOU Loke Ming YANG Shengyun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第2期45-54,共10页
Large portions of the world's fishery resources are overexploited. Life history traits of fish species are important indicators to reveal different life history strategies and to indicate population responses to fish... Large portions of the world's fishery resources are overexploited. Life history traits of fish species are important indicators to reveal different life history strategies and to indicate population responses to fishing pressures. For this study, empirical data on fishing grounds located in the coastal area between Fujian Coast and Taiwan Island were collected. These areas have experienced severe overfishing in the past 30 years, leading to changes in the structure and function of the fish communities. Fifty-one commercial fish species in this fishing ground were selected to study the life history traits. Using the life history traits, all the species were grouped into five different life history strategies by principle component analysis. More than 60% of the species were categorized in Group 5 that was similar to r-strategists. Twenty-five commercial species were selected for further analysis of changes in life history variables, and to discuss the population responses to exploitation. Results showed that most of the species appeared to become smaller size, shorter life, earlier maturation and faster growing under long-term exploitation. The exploitation rate of each species was also calculated to further discuss the impacts of fishing pressures to fish populations. Four species were found with the severest changes on life history traits indicating some of the species might be more susceptible to exploitation. This study on fish life history traits and their long-term variations under fishing pressures could provide important scientific implications for fishery management and conservation. 展开更多
关键词 life history traits fish life history strategy fishery exploitation the Taiwan Strait
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Age structure and static life tables of the endangered Juniperus phoenicea L. in North Sinai Mountains, Egypt:implication for conservation 被引量:5
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作者 Emad A.FARAHAT 《Journal of Mountain Science》 SCIE CSCD 2020年第9期2170-2178,共9页
Studying the population ecology of endangered plants provides important baseline information for its monitoring and conservation.Juniperus phoenicea L.is an endangered species in arid ecosystems in Africa and the Midd... Studying the population ecology of endangered plants provides important baseline information for its monitoring and conservation.Juniperus phoenicea L.is an endangered species in arid ecosystems in Africa and the Middle East.The static life tables,survival curve and age structure of J.phoenicea populations from two mountains in North Sinai,Egypt(Gabal(G.)El-Halal and G.El-Maghara)were investigated.In each mountain,fifteen plots were selected,and field measurements such as stand density,tree height,and crown diameter were conducted.Moreover,44 trees were cored and crossdated according to standard dendrochronological procedures.The results showed that the tree ages ranged from 50 to 262 years at G.El-Halal and 96 to431 years at G.El-Maghara.Mature J.phoenicea individuals dominated the study area,with only a few individuals being younger than 100 years.Moreover,seedling recruitment was extremely limited.Since the studied J.phoenicea populations showed high mortality rates among both old and young individuals,there is an imminent need for establishing a conservation program to prevent its extinction in the future.Therefore,management and conservation efforts should be made to minimize human disturbance and protect the relic habitats of this endangered species at its southern distribution limits in Africa. 展开更多
关键词 Juniperus phoenicea Age distribution life history MORTALITY Endangered plant SINAI
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Application of Steel Fiber in Increasing the Strength, Life-Period and Reducing Overall Cost of Road Construction (by Minimizing the Thickness of Pavement)
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作者 Abdul Ahad Zishan Raza Khan Shumank Deep Srivastava 《World Journal of Engineering and Technology》 2015年第4期240-250,共11页
Recently, the use of steel fiber at high rates has been introduced as the sole method of reinforcement for fully elevated-suspended slabs having long span such as 5 m to 8 m each way, with a span to depth ratio of up ... Recently, the use of steel fiber at high rates has been introduced as the sole method of reinforcement for fully elevated-suspended slabs having long span such as 5 m to 8 m each way, with a span to depth ratio of up to 33 [1]. As a result of long practical experience the total replacement of traditional rebar is a new routine. Now it is also used in the designing of SFRC pavements over conventional concrete pavements. Within the project framework a demonstration of a steel-fiber-reinforced roller-compacted concrete (SFR-RCC) pavement was constructed in a rural as well as urban area. In order to assess the economical condition of the demonstration pavement, life cycle assessment (LCA) and life cycle cost analysis (LCCA) studies were undertaken. This is the advancement study of the various papers which is already published in many publications which serve as the main and important source of study for the research. Many applications of steel fiber are listed in the paper but the main output of this paper is that SFR-RCC is more economically sustainable than others and also helps in reducing the thickness of the pavement up to 20 to 25 percent, due to the excessive strength of steel fiber. The roads of the present system required high cost investment. And the life period is almost 20 years theoretically but the actual life of the road is depending on the maintenance and the applied load. The constructions of road have been done since the 3500 BC but the method does not change fully. Also the cost of the construction is increased continuously;as a result, the construction of roads is more and more complicated and time taken. For the better and economical construction of the roads, we use steel fibers in the composite pavement. The theoretical plan of the construction of composite pavement is given in the methodology, which gives the appropriate idea about the construction of road using steel fiber. Here we use the composite pavement in which the steel fiber is mixed in the concrete layer, after which the bitumen layer is laid for the smooth and suitable riding of the vehicles. 展开更多
关键词 Steel Fiber Reinforced CONCRETE (SFRC) ROADS history of ROADS life CYCLE Assessment (LCA) life CYCLE COST Analysis (LCCA) CONCRETE Reinforcement Economical Road
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A retrospective view on the history of natural sciences in XX-XXI
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作者 Vladislav Sergeyevich Olkhovsky 《Natural Science》 2010年第3期228-245,共18页
The presented paper is dedicated to a new ret-rospective view on the history of natural sci-ences in XX-XXI cc, partially including the sci-ence philosophy (mainly, the problems of the scientific realism, i.e. the cor... The presented paper is dedicated to a new ret-rospective view on the history of natural sci-ences in XX-XXI cc, partially including the sci-ence philosophy (mainly, the problems of the scientific realism, i.e. the correspondence of science to reality) and also a novel scheme for different classes of sciences with different ob-jects and paradigms. There are analyzed the chosen “great” and “grand” problems of phys-ics (including the comprehension of quantum mechanics, with a recently elaborated new chapter, connected with time as a quantum obs- ervable and time analysis of quantum processes) and also of natural sciences as a whole. The particular attention is paid to the interpretation questions and slightly to the aspects, inevitably connected with the world- views of the res- earchers (which do often constitute a part of the interpretation questions). 展开更多
关键词 SCIENCE history SCIENCE realism paradigm PROBLEM of interpretation and comprehension of QUANTUM mechanics the WAVE-FUNCTION collapse the Einstein-Podolsky-Rosen paradox TIME as a QUANTUM observable canonically conjugated to energy maximal hermitian TIME operator TIME analysis of QUANTUM processes relationship be-tween physics and biology PROBLEM of origin of biologic life REDUCTIONISM cosmologic PROBLEM Big Bang anthropic principle
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Laboratory culture of the freshwater benthic gastropod Bellamya aeruginosa (Reeve) and its utility as a test species for sediment toxicity 被引量:23
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作者 Taowu Ma Shuangjiao Gong +4 位作者 Ke Zhou Cheng Zhu Kaidong Deng Qinghua Luo Zijian Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第2期304-313,共10页
This study aimed to develop original laboratory culture and sediment toxicity testing protocols for the freshwater gastropod Bellamya aeruginosa (Reeve), a new potential species for sediment toxicity testing. B. aer... This study aimed to develop original laboratory culture and sediment toxicity testing protocols for the freshwater gastropod Bellamya aeruginosa (Reeve), a new potential species for sediment toxicity testing. B. aeruginosa was successfully cultured with an effective culture system under proposed laboratory conditions. Optimal ad libitum feeding levels for larvae, juveniles, and adults were 2.0, 6.0, and 16.0 mg fish food/(snall.day), respectively. Mean survival rates of juveniles were higher than 90%, The snails could be sexed at 9 weeks of age, and their generation time is approximately 4 months. Reproduction continued all year around; the mean fecundity was 0.55 newborn/(female.day). The utility of this species for bioassays was evaluated in both 10-day and 28-day case studies with artificial sediments. The 10-day LC50 of Cu for larvae was 480 μg/g dry weight (dw), and the lowest observed effects concentration of Cu for survival and growth of larvae was 195 μg/g dw. Survival and growth are reliable indicators of acute toxicity. Larvae accumulated more Cu than adults. B. aeruginosa exhibited a higher sensitivity to Cu exposure than standard test species (Hyalella azteca and Chironomus tentans). The 28-day test of sediment toxicity with adults showed that fecundity was a robust endpoint indicator of reproductive toxicity, and the biochemical endpoints of superoxide dismutase, catalase, and glutathione could be used as sensitive biomarkers for Cu-induced oxidative damage. B. aeruginosa can be therefore recommended as a candidate for the standardization of the freshwater sediment toxicity test protocol. 展开更多
关键词 GASTROPOD CULTURES life history lowest observed effect concentration BIOACCUMULATION oxidative stress
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Larval diet affects development and reproduction of East Asian strain of the fall armyworm,Spodoptera frugiperda 被引量:12
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作者 HE Li-mei WANG Teng-li +3 位作者 CHEN Yu-chao GE Shi-shuai Kris AGWYCKHUYS WU Kong-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第3期736-744,共9页
In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded China and has since impacted local maize,sorghum and other crops.Here,we draw on laboratory experiments to show how different host crops(i.e.,ma... In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded China and has since impacted local maize,sorghum and other crops.Here,we draw on laboratory experiments to show how different host crops(i.e.,maize,sorghum,wheat and rice)and artificial diet affect larval growth and adult reproduction of one local FAW strain.Larval diet affected development duration,pupation rate,survival and emergence rate of pupae,and S.frugiperda adult fecundity.FAW attained the slowest larval development(19.4 days)on sorghum and the fastest(14.1 days)on artificial diet,with larvae attaining 99.6%survival on the latter food item.On rice,FAW larvae attained survival rate of 0.4%and were unable to pupate successfully.Pupation rate and pupal survival varied substantially between artificial diet and live plantlets at different phenological stages.Pupal weight was the highest(0.26 g)on artificial diet and the lowest(0.14 g)on sorghum,while FAW females reached the highest fecundity(699.7 eggs/female)on 2-leaf stage maize.Egg hatching rate equaled 93.6%on 4-or 5-leaf stage maize and 36.6%on artificial diet.FAW intrinsic rate of natural increase and the finite rate of increase varied between larval diets,reflecting how young maize leaves are the most suitable diet.Our findings can help to refine laboratory rearing protocols,devise population forecasting models or guide the deployment of‘area-wide’integrated pest management(IPM)modules in FAW-invaded areas of China and other Asian countries. 展开更多
关键词 developmental duration DEVELOPMENT FECUNDITY life history insect mass-rearing biology invasion biology
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Population life tables for the invasive fall armyworm,Spodoptera frugiperda fed on major oil crops planted in China 被引量:9
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作者 HE Li-mei WU Qiu-lin +1 位作者 GAO Xi-wu WU Kong-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第3期745-754,共10页
The fall armyworm(FAW),Spodoptera frugiperda,is a newly invasive,widespread agricultural pest in China.Understanding the suitability of the main field crops in Chinese agricultural system as host for this polyphagous ... The fall armyworm(FAW),Spodoptera frugiperda,is a newly invasive,widespread agricultural pest in China.Understanding the suitability of the main field crops in Chinese agricultural system as host for this polyphagous herbivore is especially important for making control strategy.Here,after FAWs were fed three important oil-bearing crops(oilseed rape,soybean and sunflower)planted in China and resultant population parameters were compared using the age-stage,two-sex life table method,survival of larvae on soybean was significantly lower than that on oilseed rape and sunflower.Developmental duration of larvae on soybean was also the longest(23.3 days).The highest pupation rate was recorded on sunflower.The highest pupal mass(0.19 g)was attained on oilseed rape,significantly higher than on the other host plants;the lowest mass was on soybean(0.15 g).On soybean,oilseed rape and sunflower,respectively,the average generation period was 42.21,39.10 and 40.44 d;the intrinsic rate of increase(r)was 0.0844,0.1041 and 0.1134;the finite rate of increase(λ)was 1.0881,1.1098 and 1.1202.While the most suitable host plant overall was sunflower,S.frugiperda completed development and increased its population on all three host plants.Thus,soybean,oilseed rape and sunflower were all suitable for FAW,and population monitoring and management of FAW in these crops should be increased. 展开更多
关键词 developmental duration FECUNDITY life history oil-bearing crops BIOLOGY invasion biology
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Changes in the population structure of Calanus sinicus during summer–autumn in the southern Yellow Sea 被引量:2
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作者 Yongqiang Shi Song Sun +3 位作者 Chaolun Li Guangtao Zhang Bo Yang Peng Ji 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第8期56-63,共8页
Calanus sinicus is a calanoid copepod widely distributed in coastal waters of China and Japan, and oversummering strategies may have major impacts on their population dynamics which in turn affect local marine food we... Calanus sinicus is a calanoid copepod widely distributed in coastal waters of China and Japan, and oversummering strategies may have major impacts on their population dynamics which in turn affect local marine food web structure. The abundance, stage composition, and sex composition of the planktonic copepod C. sinicus were studied from August to October 2002 in the southern Yellow Sea to understand how its population recovers from the over-summering state. Results showed that C. sinicus had low reproduction in August due to high temperature, except in waters near the Cheju Island with rich food and moderate bottom temperature, but the reproduction rates here decreased in September–October as food availability declined. When temperature dropped in September–October, C. sinicus actively propagated in coastal shallow waters. However, reproduction rates of C. sinicus individuals inhabiting the Yellow Sea Cold Water Mass(YSCWM) remained low during the three months of the study. The percentage of C. sinicus females was high during the reproductive period, which suggests that the sex composition of adult C. sinicus may reflect whether or not the population is in the reproductive mode.Numerous fifth copepodite stage(CV) C. sinicus aggregated in the YSCWM in a suspended developmental stage during the three months of this study, and they potentially served as the parental individuals for population development when conditions became optimal for reproduction later in the year. 展开更多
关键词 CALANUS SINICUS stage COMPOSITION SEX COMPOSITION population structure YELLOW Sea Cold Water Mass life history strategy
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Age and Body Size of the Shangcheng Stout Salamander Pachyhynobius shangchengensis(Caudata:Hynobiidae)from Southeastern China 被引量:2
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作者 Jianli XIONG Jianping GOU +3 位作者 Yong HUANG Baowei ZHANG Hongtao REN Tao PAN 《Asian Herpetological Research》 SCIE CSCD 2020年第3期219-224,共6页
Age and body size a re critical for understanding life history evolution and ecology.In this study,the age and body size of the Shangcheng stout salamander,Pachyhynobius shangchengensis,from a population in Anhui Prov... Age and body size a re critical for understanding life history evolution and ecology.In this study,the age and body size of the Shangcheng stout salamander,Pachyhynobius shangchengensis,from a population in Anhui Province,China,were studied by skeletochronology.The mean age was 8.8±0.2(mean±SD)years in females and 9.6±0.2 in males and ranged 5-13 years for both sexes.The mean age was significantly different between sexes.The mean body size and mass were(100.21±0.91)mm and(31.76±0.73)g in females,and(105.31±1.23)mm and(37.14±1.12)g in males,respectively.Males were significantly larger and heavier than females,indicating sexual size dimorphism.There was a significant positive correlation among body size,body mass,and age,suggesting that the oldest individuals are larger and heavier.The growth rate in males was significantly higher than in females.The present study provides preliminary data on life-history traits which can be helpful for future studies of this species and other hynobiid salamanders. 展开更多
关键词 age structure growth rate life history SKELETOCHRONOLOGY
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