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Asexual Reproduction of Aurelia coerulea Polyps in situ on Settling Plates in Jiaozhou Bay,China
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作者 MI Tiezhu ZHU Jianbin +2 位作者 ZHEN Yu WANG Guoshan WANG Jianyan 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第5期1371-1380,共10页
Jellyfish blooms are increasingly prevalent coastal phenomena,with Aurelia coerulea being a significant contributor.The complex life history of jellyfish,featuring a sessile polyp stage,is a key factor in bloom format... Jellyfish blooms are increasingly prevalent coastal phenomena,with Aurelia coerulea being a significant contributor.The complex life history of jellyfish,featuring a sessile polyp stage,is a key factor in bloom formation,yet it is challenging to study in the field.This study aimed to describe the asexual reproduction of A.coerulea polyps in Jiaozhou Bay,China,and to assess their ability to form sedentary colonies and their relationship with environmental factors.Using settling plates,we observed polyps in situ and documented three asexual reproduction modes:budding,strobilation,and podocyst formation.Environmental parameters including temperature,salinity,dissolved oxygen(DO),chlorophyll a(Chl a),and the biomass of phytoplankton and zooplankton were monitored.Budding was the predominant reproductive method,featuring stolon budding in autumn and direct budding during the winter and spring seasons.Strobilation took place in the colder months,releasing ephyrae between April and May.Polyp abundance was positively correlated with seawater temperature and negatively correlated with DO concentration.Polyps at 1.0 m depth showed higher survivorship and proliferation over 8 months,whereas those at 2.0 m depth experienced a steady decline and died within 4 months.The study enhances our understanding of the life cycle and asexual reproduction strategies of A.coerulea polyps in the field,with implications for predicting and managing jellyfish blooms.The findings underscore the importance of temperature and DO in polyp survival and suggest that initial polyp population proliferation is crucial for long-term survival. 展开更多
关键词 jellyfish bloom POLYPS BUDDING strobilation asexual reproduction
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The life-history trait trade-offs mediated by reproduction and immunity in the brown planthopper,Nilaparvata lugens Stål
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作者 Dan Sun Hongfeng Wang +4 位作者 Jiahui Zeng Qiuchen Xu Mingyun Wang Xiaoping Yu Xuping Shentu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期2018-2032,共15页
Reproduction and immune defense are costly functions,and they are expected to tradeoff with each other to drive evolution.The brown planthopper(BPH),Nilaparvata lugens Stål(Hemiptera,Delphacidae),is a global supe... Reproduction and immune defense are costly functions,and they are expected to tradeoff with each other to drive evolution.The brown planthopper(BPH),Nilaparvata lugens Stål(Hemiptera,Delphacidae),is a global superpest that mostly damages rice crops.Yeast-like symbionts(YLS)exist in the abdominal fat body tissue and are tightly associated with the development,growth,and reproduction of BPH.Our previous research demonstrated that mating behavior promotes the release of YLS from the fat body into the hemolymph in the BPH,thereby triggering an immune response.Additionally,the fitness costs related to life-history traits of BPH(such as survival rate)have a strong dependence on the relative abundance of YLS.However,the possible relationship between reproduction and the immune response in BPH has not been identified.In this study,an omics-based approach was used to analyze the transcriptome of fat body tissues in mated and unmated BPH at 72 h post-eclosion,from which two antimicrobial peptide genes,NlDefensin A(NlDfA)and NlDefensin B(NlDfB),were selected since they were highly expressed in mated BPH.Subsequently,the full-length cDNA sequences of the NlDfA and NlDfB genes were cloned and analyzed.qPCR results showed up-regulation of the NlDfA and NlDfB genes in mated BPH when compared to unmated BPH.Spatial-temporal expression analysis indicated that the NlDfA and NlDfB genes were expressed in all tissues and developmental stages,and they were most highly expressed in the fat body at 24 h post-eclosion.Moreover,the symbionts in BPH were significantly inhibited by the in vitro expression of the NlDfA and NlDfB proteins.Furthermore,RNA interference(RNAi)-mediated suppression of NlDfA and NlDfB dramatically increased the relative abundance of YLS in the fat body,while YLS in the hemolymph decreased significantly.These BPHs also displayed some fitness disadvantages in survival,fecundity,hatchability,and possibly the vertical transmission of YLS from hemolymph to egg.Our results indicated that mating could heighten the immunity of BPH by upregulating the expression of the NlDfA and NlDfB genes,which protect the host from pathogen challenges during reproduction.However,the reduced content of YLS may act as a fitness disadvantage in dictating the life-history traits of BPH.This work has significant theoretical and practical implications for the precise green control technology that involves crucial gene targeting,as well as for the“endosymbionts for pest control”strategy in insects. 展开更多
关键词 Nilaparvata lugens reproduction immune defense trade-off
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Tissue distribution of cadmium and its effect on reproduction in Spodoptera exigua
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作者 Honghua Su Menglu Wu +3 位作者 Yong Yang Yan Deng Yizhong Yang Qingming Sun 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期195-204,共10页
Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua... Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua exposed to cadmium and its effects on the growth and development of the parents and the offspring were investigated.Under the stress of different concentrations of cadmium(0.2,3.2,and 51.2 mg kg^(-1)),the cadmium content in each tissue of S.exigua increased in a dose-dependent manner.At the larval stage,the highest cadmium accumulation was found in midgut in all three cadmium treatments,but at the adult stage,the highest cadmium content was found in fat body.In addition,the cadmium content in ovaries was much higher than in testes.When F1S.exigua was stressed by cadmium and the F_(2)generation was not fed a cadmium-containing diet,the larval survival,pupation rate,emergence rate and fecundity of the F_(2)generation were significantly reduced in the 51.2 mg kg^(-1)treatment compared to the corresponding F1generation.Even in the F_(2)generation of the 3.2 mg kg^(-1)treatment,the fecundity was significantly lower than in the parental generation.The fecundity of the only-female stressed treatment was significantly lower than that of the only-male stressed treatment at the 3.2 and 51.2 mg kg^(-1)cadmium exposure levels.When only mothers were stressed at the larval stage,the fecundity of the F_(2)generation was significantly lower than that of the F1generation in the 51.2 mg kg^(-1)treatment,and it was also significantly lower than in the 3.2 and 0.2 mg kg^(-1)treatments.The results of our study can provide useful information for forecasting the population increase trends under different heavy metal stress conditions and for the reliable environmental risk assessment of heavy metal pollution. 展开更多
关键词 heavy metal pollution CADMIUM Spodoptera exigua tissue distribution reproduction
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Sex-specific facilitation and reproduction of the gynodioecious cushion plant Arenaria polytrichoides on the Himalaya-Hengduan mountains,SW China
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作者 Xufang Chen Yazhou Zhang +3 位作者 Lishen Qian Renyu Zhou Hang Sun Jianguo Chen 《Plant Diversity》 SCIE CAS CSCD 2024年第2期247-255,共9页
When benefiting other beneficiaries,cushion plants may reciprocally receive feedback effects.The feedback effects on different sex morphs,however,remains unclear.In this study,taking the gynodioecious Arenaria polytri... When benefiting other beneficiaries,cushion plants may reciprocally receive feedback effects.The feedback effects on different sex morphs,however,remains unclear.In this study,taking the gynodioecious Arenaria polytrichiodes as a model species,we aimed to assess the sex-specific facilitation intensity of cushion plant by measuring the beneficiary cover ratio,and to assess the potential costs in cushion reproductive functions by measuring the flower and fruit cover ratios.The total beneficiary cover ratio was similar between females and hermaphrodites.Females produced much less flowers but more fruits than hermaphrodites.These results suggested that females and hermaphrodites possess similar facilitation intensity,and female cushion A.polytrichoides may allocate more resources saved from pollen production to seed production,while hermaphrodites possibly allocate more resources to pollen production hence reducing seed production.The surface areas covered by beneficiaries produced less flowers and fruits than areas without beneficiaries.In addition,strong negative correlations between beneficiary cover and flower cover were detected for both females and hermaphrodites,but the correlation strength were similar for these two sex morphs.However,the correlation between beneficiary cover and fruit cover was only significantly negative for females,suggesting that beneficiary plants negatively affect fruit reproduction of females while have neutral effects on hermaphrodites.All the results suggest that to facilitate other beneficiaries can induce reproductive costs on cushion A.polytrichoides,with females possibly suffering greater cost than hermaphrodites.Such differentiation in reproductive costs between sex morphs,in long-term perspective,may imply sex imbalance in population dynamics. 展开更多
关键词 Facilitation intensity Feedback effect Sex-specific facilitation Nurse plant Population dynamics Reproductive function
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Scale Breeding and Reproduction Technique of Ficus tikoua Bur.Container Seedlings
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作者 Tinghong TAN Fan GAO +5 位作者 Yang XIAO Mingxing DAI Shunping BAI Shimei LIAO Chaojun FENG Chunfang WU 《Plant Diseases and Pests》 CAS 2023年第5期16-18,23,共4页
Based on the principle of asexual reproduction,a kind of scale breeding and reproduction technique of Ficus tikoua Bur.container seedlings was explored by using the characteristics of strong adaptability to the enviro... Based on the principle of asexual reproduction,a kind of scale breeding and reproduction technique of Ficus tikoua Bur.container seedlings was explored by using the characteristics of strong adaptability to the environment and fast growth and reproduction.Using non-woven bag as a breeding container for seedlings,the scale breeding and reproduction technique of F.tikoua container seedlings was summarized through the important links of seedling bed construction,seedling collection,soil configuration,container selection,cutting cultivation,field management,and disease and pest control.This technique can achieve differential,massive and sustainable efficient breeding and reproduction of F.tikoua seedlings in a short time. 展开更多
关键词 Ficus tikoua Bur Pharmaceutical/food resource Asexual reproduction Container seedling Scale breeding and reproduction
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EcR/USP-1-mediated ecdysteroid signaling regulates wolf spider(Pardosa pseudoannulata) development and reproduction
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作者 Zhi-Ming Yang Yang-Yang Yan +2 位作者 Yong Wu Na Yu Ze-Wen Liu 《Zoological Research》 SCIE CAS CSCD 2023年第1期43-52,共10页
Lycosidae females demonstrate meticulous maternal care of offspring by carrying egg sacs and juvenile spiderlings during the reproductive stage. Nuclear receptors(NRs), especially the ecdysone receptor(EcR) and ultras... Lycosidae females demonstrate meticulous maternal care of offspring by carrying egg sacs and juvenile spiderlings during the reproductive stage. Nuclear receptors(NRs), especially the ecdysone receptor(EcR) and ultraspiracle(USP), have attracted considerable attention in the regulation of arthropod development and reproduction due to their pivotal roles in ecdysteroid signaling cascades. In the present study, 23 NRs, including one EcR and two USPs, were identified in the genome of the predatory wolf spider Pardosa pseudoannulata. RNA interference(RNAi) targeting EcR and USP-1inhibited spiderling development and resulted in nonviable eggs in the egg sacs. EcR and USP-1responded to changes in ecdysteroid levels, and interference in ecdysteroid biosynthesis led to similar phenotypes as ds EcR and ds USP-1 treatments.These findings suggest that EcR/USP-1-mediated ecdysteroid signaling regulates P. pseudoannulata development and reproduction. The P.pseudoannulata females with suppressed ecdysteroid signaling proactively consumed their non-viable egg sacs, resulting in a 7.19 d shorter first reproductive cycle than the controls. Termination of the failed reproductive cycle enabled the spiders to produce a new egg sac more rapidly. This reproductive strategy may partially rescue the reduction in population growth due to non-viable eggs and compensate for the physiological expenditure of wasted maternal care, which would be beneficial for the conservation of P.pseudoannulata populations and their natural control of insect pests. 展开更多
关键词 Pardosa pseudoannulata Ecdysone receptor ULTRASPIRACLE DEVELOPMENT reproduction
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Performance in Survival,Development and Reproduction of Aphis glycines Matsumura Virginoparae at High Temperatures
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作者 Liu Jian Liu Zhe +3 位作者 Wu Ci-rui Liu Dai-lin Huo Dong-bo Sun Wen-peng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2023年第1期20-27,共8页
The soybean aphid,Aphis glycines Matsumura,is an important pest of soybean,which is native to Asia.In this study,A.glycines fed on soybean(AgFS)and A.glycines fed on wild soybean(AgFW)were reared at 25℃,27℃,29℃,31... The soybean aphid,Aphis glycines Matsumura,is an important pest of soybean,which is native to Asia.In this study,A.glycines fed on soybean(AgFS)and A.glycines fed on wild soybean(AgFW)were reared at 25℃,27℃,29℃,31℃,33℃and 35℃,respectively,and some of the life parameters were determined.At temperature ranging from 25℃to 31℃,nymphs of AgFS and AgFW all developed into adults successfully.Only a few nymphs of AgFS and AgFW developed into adults at 33℃and no nymphs could develop into adults at 35℃.Lifespan,fecundity and body size of AgFS and AgFW adults all decreased gradually with temperatures increasing from 25℃to 33℃.At 25℃,the intrinsic rate of increase of AgFS was as big as that at 27℃,which was smaller than that at 29℃,but was bigger than that at 31℃.Intrinsic rate of increase of AgFW decreased gradually with temperatures increasing from 25℃to 31℃.Nymph stage duration of AgFW was longer than or as long as that of AgFS;adult lifespan of AgFW was shorter than or as long as that of AgFS.Adult fecundity,intrinsic rate of increase and adult body size of AgFW were all smaller than or as big as those of AgFS.It showed that AgFS and AgFW both survived and developed well at temperature ranging from 25℃to 31℃,and AgFW was more adaptive to low temperatures.These results were important to study the adaptability of A.glycines to high temperatures and for predicting its dynamics in the temperature keeping rising region. 展开更多
关键词 Aphis glycines Matsumura DEVELOPMENT reproduction high temperature
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Effects of Different Levels of Garlic Powder Incorporated in the Feed Enriched with Stylosanthes guianensis on Reproduction and Pre-Weaning Growth Performances of Cavies (Cavia porcellus)
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作者 Martin Vidal Tatang Emile Miégoué +6 位作者 Margaret Mary Momo Chongsi Wouafo David Fokom Nyah Cédric Kwayep Paulette Ntsafack Tobou France-Gina Djoumessi Mathieu Duclos Fogang Fernand Tendonkeng 《Open Journal of Animal Sciences》 2023年第4期574-589,共16页
In order to increase the productivity of the local cavies as a meat animal, a study was carried out between November 2021 and March 2022 at the Research and Experimental Farm, Animal Nutrition and Production Research ... In order to increase the productivity of the local cavies as a meat animal, a study was carried out between November 2021 and March 2022 at the Research and Experimental Farm, Animal Nutrition and Production Research Unit of the Faculty of Agronomy and Agricultural Sciences (FAAS) and the Microbiology and Anti-Microbial Research Unite of the University of Dschang on 72 cavies aged between 4 and 5 months and weighing an average of 450 ± 50 g produced on the farm, including 60 females and 12 males. The females were distributed according to a completely randomized factorial design in twelve (12) rearing boxes numbered G1 to G12, with 15 females per group distributed in 03 boxes and receiving iso-nitrogenated experimental diet (18% protein) R0 enriched with 20% of Stylosanthes guianensis (0% garlic powder), R0.25 (0.25% garlic powder), R0.50 (0.50% garlic powder) and R0.75 (0.75% garlic powder). Females were identified by numbered ear tags and mated with a sex ratio of 5 females for 1 male. Drinking water enriched with vitamin C (01 tablet of 240 mg in 1.5 liters of water) was served ad libitum and renewed daily. The males were removed after 31 days. A form was established to record the weight of each pregnant female, any abortions during gestation, the date of parturition and the date of birth of each newborn, as well as the number of live-born or stillborn pups. After parturition, the weights of female and newborn cavies were recorded weekly until the 3<sup>rd</sup> week. The number of cavies that died before weaning and the number of live weaned cavies were also recorded. Reproductive performance significantly increased (p 0.05) fertility rate and net fertility rate, litter size, birth viability rate, and pre-weaning viability rate with rations containing garlic powder, compared to the control ration, especially with the R0.50 ration. In addition, birth mortality and pre-weaning mortality were significantly lower (p 0.05) with rations containing the additive, compared to those of the control ration (R0). However, the R0.50 ration showed the lowest rates, followed by the R0.25 ration, and finally the R0.75 ration. Weight development of young cavies increased with all rations but was more marked with the R0.50 ration. Only total weight gain (TG) and average daily weight gain (ADG) in the pre-weaning phase were significantly increased (p < 0.05) with rations R0.25 and R0.50. 展开更多
关键词 Cavy Garlic Powder Pre-Weaning Growth reproduction Stylosanthes guianensis
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Russian Collaborative Development of Reproduction Technologies for the Sustainable Management of Amphibian Biodiversity
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作者 Victor K.UTESHEV Edith N.GAKHOVA +5 位作者 Ludmila I.KRAMAROVA Natalia V.SHISHOVA Svetlana A.KAUROVA Elena A.KIDOVA Artem A.KIDOV Robert K.BROWNE 《Asian Herpetological Research》 SCIE CSCD 2023年第1期103-115,共13页
Reproduction technologies(RTs)can provide for the reliable reproduction of amphibians,as well as perpetuation of species genetic variation with the use of biobanks.In 1982,in anticipation of the biodiversity conservat... Reproduction technologies(RTs)can provide for the reliable reproduction of amphibians,as well as perpetuation of species genetic variation with the use of biobanks.In 1982,in anticipation of the biodiversity conservation crisis,major Russian institutions collaborated in a dynamic program to develop and implement RTs for the sustainable management of amphibian biodiversity.An initial primary focus was the captive breeding of threatened Russian endemic anuran and caudate species,using RTs that varied from environmental manipulation to the use of exogenous gonadotropic hormones to stimulate reproduction.These species were mostly from Palearctic or cool mountain regions,but also included a wide range of species from warm regions.Other early achievements included the successful cryopreservation of anuran spermatozoa and anuran diploid pluripotent cell nuclei,in order to store both the matrilineal and patrilineal genomes in biobanks,with their subsequent development to the blastula stage after implantation into enucleated oocytes.After the turn of the 21st Century,in support of the priorities of the Amphibian Conservation Action Plan(2007),we developed RTs for the refrigerated storage of testicular or urinary spermatozoa for days to weeks at 4℃,the cryopreservation of urinary spermatozoa using anovel cryoprotectant,the in vitro fertilisation of hormonally induced oocytes either fresh or after refrigerated ex situ or in situ storage,and the artificial insemination of salamanders with fresh spermatozoa.In this article,we describe previously unpublished techniques and techniques from obscure Russian sources. 展开更多
关键词 artificial fertilisation assisted reproductive technologies(ART) CRYOPRESERVATION gonadotropic hormones OOCYTES SPERMATOZOA storage urinary spermatozoa
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Anti-Müllerian Hormone and Its Utility in Cattle Reproduction
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作者 Garza Arredondo Aimé Jazmín Moreno Degollado Gustavo +4 位作者 Adolfo-Soto Dominguez Pérez Hernández Raymundo Alejandro Rosales S. Cedillo Zamora-Ávila Diana Castillo-Velázquez Uziel 《Open Journal of Veterinary Medicine》 CAS 2023年第1期1-11,共11页
Reproductive biotechnologies offer us greater possibilities to improve animal genetics. However, the success of these depends on different factors such as the proper selection of the donor female. For this reason, end... Reproductive biotechnologies offer us greater possibilities to improve animal genetics. However, the success of these depends on different factors such as the proper selection of the donor female. For this reason, endocrine markers have been used to evaluate the ovarian reserve, which allow a successful selection of donors. Recent research has shown, among other things, that concentrations greater than 0.130 ng/mL of anti-Mullerian hormone (also known as Muller-inhibiting substance, which is a member of the transforming growth factor beta superfamily of growth and differentiation factors) are related to donors of more than fifteen transferable embryos. Therefore, this review describes studies showing that the measurement of anti-Müllerian hormone concentrations, before superovulation programs, reduces the costs per embryo produced. 展开更多
关键词 AMH Anti-Müllerian Hormone Reproductive Techniques Follicular Population Granulosa Cells SUPEROVULATION
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ISSUES AND MEASURES ON ASSISTED REPRODUCTION BY ACUPUNCTURE ABROAD 被引量:2
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作者 彭艳 丛晶 +1 位作者 侯丽辉 吴效科 《World Journal of Acupuncture-Moxibustion》 2007年第2期31-34,共4页
As the application of acupuncture has been increased year by year in the field of overseas reproduction, it has become crucial to give a scientific and objective evaluation of the safety and efficacy of acupuncture in... As the application of acupuncture has been increased year by year in the field of overseas reproduction, it has become crucial to give a scientific and objective evaluation of the safety and efficacy of acupuncture in the field of assisted reproduction, which attaches great importance to the sustainable development of acupuncture in the field of reproduction. This article aims to introduce the current situation of overseas clinical study in the field of assisted reproduction, analyze the existing issues profoundly and put forward measures to solve them, in order to enhance the level of international clinical study of acupuncture. 展开更多
关键词 Acupuncture Assisted reproduction Clinical study
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Research on Development Mode of Solid Ancient Towns Based on Cultural Reproduction——A Case Study of Zouma Ancient Town in China 被引量:1
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作者 陈琴 李俊 张述林 《Journal of Landscape Research》 2011年第8期28-31,共4页
The paper had pointed out hollow ancient town was the result of urbanization and desire; and analyzed that hollowness made ancient towns degenerate in nature, economy and social function, seriously blocking the sustai... The paper had pointed out hollow ancient town was the result of urbanization and desire; and analyzed that hollowness made ancient towns degenerate in nature, economy and social function, seriously blocking the sustainable development of economic society of ancient towns. Based on the connotation and idea of cultural reproduction, in terms of application of basic theories of cultural ecology and restoration ecology, it had established tourism development of solid ancient towns, which had been analyzed specifically from the perspectives of representation of ancient towns'scene, cultural realization and cultural promotion. By taking Zouwa Ancient Town in the west of the main urban area of Chongqing City for example, it had discussed tourism development practice of ancient towns, emphasized making Zouma scene reappear from the aspects of pattern protection, restoration and treatment of ecological environment, ancient towns' protection and cultural facilities' construction, experiencing and publicizing Zouma culture. It also highlighted taking historical and cultural heritages as the theme of tourist products, and proposed development mode of solid ancient towns, realizing reproduction of cultural heritage. 展开更多
关键词 HOLLOW ANCIENT TOWNS CULTURAL reproduction Development mode Solidness
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ON THE BASIC REPRODUCTION NUMBER OF GENERAL BRANCHING PROCESSES 被引量:1
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作者 蓝国烈 马志明 孙苏勇 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期1081-1094,共14页
Under a very general condition (TNC condition) we show that the spectral radius of the kernel of a general branching process is a threshold parameter and hence plays a role as the basic reproduction number in usual ... Under a very general condition (TNC condition) we show that the spectral radius of the kernel of a general branching process is a threshold parameter and hence plays a role as the basic reproduction number in usual CMJ processes. We discuss also some properties of the extinction probability and the generating operator of general branching processes. As an application in epidemics, in the final section we suggest a generalization of SIR model which can describe infectious diseases transmission in an inhomogeneous population. 展开更多
关键词 general branching process extinction probability reproduction kernel spectral radius TNC condition basic reproduction number SIR model
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Advances in Small RNAs and Sexual Reproduction in Plants
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作者 王俊 何桥 +5 位作者 汪卫星 向素琼 孙海艳 李晓林 梁国鲁 郭启高 《Agricultural Science & Technology》 CAS 2013年第2期211-214,229,共5页
Small RNAs are non-coding RNA molecules with 20-30 nucleotides (nt) in length that mainly play regulatory roles in gene expression at the post-transcription level by directly cutting target mRNA or inhibiting its tr... Small RNAs are non-coding RNA molecules with 20-30 nucleotides (nt) in length that mainly play regulatory roles in gene expression at the post-transcription level by directly cutting target mRNA or inhibiting its translation. Small RNAs play regulatory roles in the growth and development process of plants at the core of gene regulatory networks, which has been widely studied and confirmed in sporophyte generation of plants. However, few researches have been conducted on small RNAs and gametophyte generation. It is reported that small RNAs play important roles in floral organ development, gametogenesis, fertilization, and early zygotic development of plants. In addition, various small RNAs also play roles in controlling genetic integrity, cell differentiation and functions during the sexual reproduction process of plants. However, most of the specific functions of small RNAs in the sexual reproduction process are unknown yet. This study mainly aimed to introduce small RNAs in plants, summarize the latest advances in researches of small RNAs and plant sexual reproduction, and make prospect on its future. 展开更多
关键词 Small RNA Sexual reproduction Floral organ development GAMETOGENESIS FERTILIZATION Early zygotic development
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Study on Flowering, Cultivation, and Reproduction of Agave americana Var. Marginata Hort. (Agavaceae) 被引量:2
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作者 刘方农 彭世逞 刘联仁 《Agricultural Science & Technology》 CAS 2012年第9期1864-1869,共6页
Agave americana Var. Marginata Hort. (Agavaceae) is a perennial herb. This paper summarized its classification, distribution, morphological characteristics, habit, flowering and fruiting, cultivation and reproductio... Agave americana Var. Marginata Hort. (Agavaceae) is a perennial herb. This paper summarized its classification, distribution, morphological characteristics, habit, flowering and fruiting, cultivation and reproduction, as well as multiple uses in daily life, which provided references for the exploitation and utilization of Agave americana Vat. Marginata Hort. (Agavaceae). 展开更多
关键词 Agave americana Var. Marginata Hort. (Agavaceae) Flowering andfruiting Cultivation and reproduction Multiple uses
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The role of dietary fibre in pig production,with a particular emphasis on reproduction 被引量:16
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作者 Selene Jarrett Cheryl J.Ashworth 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第4期783-793,共11页
Fibres from a variety of sources are a common constituent of pig feeds. They provide a means to utilise locallyproduced plant materials which are often a by-product of the food or drink industry. The value of a high f... Fibres from a variety of sources are a common constituent of pig feeds. They provide a means to utilise locallyproduced plant materials which are often a by-product of the food or drink industry. The value of a high fibre diet in terms of producing satiety has long been recognised. However the addition of fibre can reduce feed intake, which is clearly detrimental during stages of the production cycle when nutrient needs are high, for example in growing piglets and during lactation. More recently, fibre has been found to promote novel benefits to pig production systems,particularly given the reduction in antimicrobial use world-wide, concern for the welfare of animals fed a restricted diet and the need to ensure that such systems are more environmentally friendly. For example, inclusion of dietary fibre can alter the gut microbiota in ways that could reduce the need for antibiotics, while controlled addition of certain fibre types may reduce nitrogen losses into the environment and so reduce the environmental cost of pig production.Of particular potential value is the opportunity to use crude fibre concentrates as ’functional’ feed additives to improve young pig growth and welfare. Perhaps the greatest opportunity for the use of high fibre diets is to improve the reproductive efficiency of pigs. Increased dietary fibre before mating improves oocyte maturation, prenatal survival and litter size; providing a consumer-acceptable means of increasing the amount of saleable meat produced per sow. The mechanisms responsible for these beneficial effects remain to be elucidated. However, changes in plasma and follicular fluid concentrations of key hormones and metabolites, as well as effects of the hypothalamic satiety centre on gonadotrophin secretion and epigenetic effects are strong candidates. 展开更多
关键词 FIBRE PIG PREGNANCY Production reproduction
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Impact of the Three Gorges Dam on reproduction of four major Chinese carps species in the middle reaches of the Changjiang River 被引量:19
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作者 黎明政 段中华 +2 位作者 高欣 曹文宣 刘焕章 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第5期885-893,共9页
Silver carp(Hypophthalmichthys molitrix),bighead carp(Aristichthys nobilis),grass carp(Ctenopharyngodon idella),and black carp(Mylopharyngodon piceus) are the four major Chinese carps and are commercially important aq... Silver carp(Hypophthalmichthys molitrix),bighead carp(Aristichthys nobilis),grass carp(Ctenopharyngodon idella),and black carp(Mylopharyngodon piceus) are the four major Chinese carps and are commercially important aquaculture species in China.Reproduction of these carp has declined since the construction of the Three Gorges Dam(TGD) due to an altered water flow and thermal regime in the Changjiang(Yangtze) River.However,details of the changes in reproduction of the four species are not well understood.To assess the impact of the TGD on reproduction of the four carp,we investigated their eggs and larvae at Yidu City,which is 80 km below the TGD,during 2005-2012.We examined differences in larval abundance of the four species in the Jianli section(350 km downstream of the TGD) before(1997-2002)and after(2003-2012) construction of the TGD.Based on these observations,the first spawning date of the four species was delayed a mean of about 25 days after the dam was constructed.Mean egg abundance in the Yidu section of the river was 249 million and mean larval abundance was 464 million,which were significant decreases since the 1980 s.Moreover,larval abundance in the Jianli section after the dam was constructed was significantly lower than that before construction(ANCOVA,P<0.05).The observed larval abundance accounted for only 24.66%of the predicted value in 2003 when the dam was first inundated.The present spawning grounds between the TGD and Yidu section of the river are very similar to those described in the 1980 s,and some spawning grounds exist upstream of the TGD.Large free-flowing stretches upstream of the TGD and the creation of artificially flooded downstream reaches are needed to stimulate spawning and effectively conserve these four major Chinese carps species. 展开更多
关键词 Changjiang(Yangtze) River Three Gorges Dam Chinese carp reproduction eggs and larvae
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Effect of temperature and irradiance on the growth and reproduction of Enteromorpha prolifera J.Ag.(Chlorophycophyta,Chlorophyceae) 被引量:8
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作者 付刚 姚建亭 +7 位作者 刘福利 刘吉东 王秀良 付万冬 李大鹏 周名江 孙松 段德麟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第4期357-362,共6页
Effect of temperature and irradiance on growth and reproduction of Enteromorpha prolifera that bloomed offshore along the Qingdao coast in summer 2008, was studied. It was showed that E. prolifera propagated mainly as... Effect of temperature and irradiance on growth and reproduction of Enteromorpha prolifera that bloomed offshore along the Qingdao coast in summer 2008, was studied. It was showed that E. prolifera propagated mainly asexually with specific growth rate (SGR) of 10.47 at 25℃/40 μmol m^-2s^-1. Under this condition, gametes with two flagellate formed and released in 5 days. At the beginning of the development, the unicell gamete divided into two cells with heteropolarity, and then the apical cell developed into thalli primordial cells, whereas the basal cell developed into rhizoid primordial cells. In 8-day culture, the monoplast gamete developed into juvenile germling of 240 μm in length. Unreleased gametes can develop directly within the alga body. E. prolifera could either reproduce through lateral branching or fragmenting except apomixis revealed by Microscopic observation. On aged tissue of E. prolifera, although the degraded pigments partially remained in faded algal filaments, numerous vegetative cells could still divide actively in the algal tissues. 展开更多
关键词 Enteromorpha prolifera growth reproduction gamete development
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The type, position and age effect on the cutting reproduction of Picea crassifolia and its rooting mechanism in the Qilian Mountains 被引量:6
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作者 Jianjun Kang Wenzhi Zhao +3 位作者 Ming Zhao Guangyu Li Jiqiang Zhang Zhisheng Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期993-1002,共10页
Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its r... Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its rooting mechanism, cuttings of P. crassifolia with different cutting types (softwood, hardwood and root), positions (top, upper, middle and bottom) and ages (7, 10, 15, 20, 25 year-old) were cultivated in a field experiment. One- year old softwood and hardwood cuttings were collected from 7-, 10-, 15-, 20-, and 25 year-old healthy ortets to analyze the changes from endogenous hormones and organic nutrients. Results indicate that the softwood cut- tings (0.5-1.0 cm in diameter) from upper branches of 15 year-old ortets shows better growth performance by improving rooting indexes, including a significant increasein rooting rate and a decrease in basal rot rate. Concomi- tantly, increasing rooting quantity and root length also increased. It is noteworthy that the high rooting rate of P. crassifolia cuttings due to its ability to accumulate high concentrations of indole-3-acetic acid (IAA) and total carbon (TC) rather than abscisic acid (ABA) and total nitrogen (TN). The rooting rate was mainly regulated by the IAA/ABA and TC/TN ratio. In summary, our results suggest that the softwood cuttings (0.5-1.0 cm in diameter) from upper branches of 15 year-old P. crassifolia can be considered as an effective strategy to improve cutting rooting rate, and the IAA/ABA and TC/TN ratio was one of the main factors limiting the cutting rooting rate of P. crassifolia. 展开更多
关键词 Picea crassifolia Kom TYPE Positionand age effect Cutting reproduction Rooting rate HORMONES Organic substances
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Adult nutrition affects reproduction and flight performance of the invasive fall armyworm,Spodoptera frugiperda in China 被引量:6
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作者 HE Li-mei JIANG Shan +5 位作者 CHEN Yu-chao Kris AGWYCKHUYS GE Shi-shuai HE Wei GAO Xi-wu WU Kong-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第3期715-726,共12页
Floral resources,such as carbohydrate-rich nectar or pollen,can bolster fitness and raise reproductive output of adult lepidopterans.Here,we used laboratory experiments to assess how those plant-derived foods impact a... Floral resources,such as carbohydrate-rich nectar or pollen,can bolster fitness and raise reproductive output of adult lepidopterans.Here,we used laboratory experiments to assess how those plant-derived foods impact adult fecundity,reproductive physiology and flight performance of an invasive strain of the fall armyworm,Spodoptera frugiperda(FAW;Lepidoptera:Noctuidae)in China.More specifically,supplementary feeding on bee pollen and honey enhanced FAW flight duration,testis size,ovarian development,longevity and adult fecundity.FAW adults attained the longest pre-oviposition(10.8 days)and oviposition period(6.8 days)and longevity(19.2 days)on 5%acacia honey.Upon access to 2.5%acacia honey and 2.5‰pine pollen,S.frugiperda attained the highest mating rate(79.7%),fecundity(644.9 eggs/female)and egg hatching rate(82.3%).Feeding on honey further delayed decay of male testes,while ovarian development was enhanced when female moths were allowed access to 2.5%honey and 2.5‰pine pollen.Upon feeding on 5%honey solution,S.frugiperda engaged in flight over the longest duration(9.5 h),distance(29.9 km)and speed(3.1 km h-1).Honey had a comparatively greater effect on the above parameters than pollen.Our findings help decipher FAW invasion patterns and population dynamics,facilitate the development of nutritional attractants,and contribute to integrated pest management of this newly-invasive pest in eastern Asia. 展开更多
关键词 supplementary nutrition FECUNDITY adult reproduction flight parameter invasion biology nutritional physiology
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