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Perspective for Vegetative Reproduction of Eleaagnus macrophylla Thunb Species and Shepherdia canadensis (L.) Nutt
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作者 Norkulova Lobar Uchkunovna Haydarov Khislat Kudratovich 《American Journal of Plant Sciences》 2025年第1期22-27,共6页
Elaeagnaceae Juss. belongs to the family Elaeagnus L. and Shepherdia Nutt. This study aims at the significance and vegetative reproduction of species of the family (Elaeagnus macrophylla Thunb. and Shepherdia canadens... Elaeagnaceae Juss. belongs to the family Elaeagnus L. and Shepherdia Nutt. This study aims at the significance and vegetative reproduction of species of the family (Elaeagnus macrophylla Thunb. and Shepherdia canadensis (L.) Nutt.) in the national economy. The trials were carried out in the experimental site of SamSU’s Botanic Garden, which is named after Sharof Rashidov. The study’s findings are based on the results obtained by planting cuttings of S. canadensis and E. macrophylla species of varying sizes and durations, as well as the cuttings’ roots and the impacts of growth chemicals. 展开更多
关键词 ELAEAGNACEAE ELAEAGNUS Shepherdia Vegetative reproduction ATTRACTIVENESS Bioactive Compound BUSH and Cuttings
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Supplementation of high levels of essential fatty acids using soybean oil in lactation diets benefits the subsequent reproduction of sows but can be detrimental to the performance of young sows if provided after weaning
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作者 Garrin Lee Shipman David Rosero Eric van Heugten 《Journal of Animal Science and Biotechnology》 2025年第4期1704-1717,共14页
Background This study investigated the potential impacts of increasing linoleic andα-linolenic acid intake during lactation and wean-to-breeding on subsequent reproduction of sows.A total of 309 sows(PIC Camborough L... Background This study investigated the potential impacts of increasing linoleic andα-linolenic acid intake during lactation and wean-to-breeding on subsequent reproduction of sows.A total of 309 sows(PIC Camborough L42)were balanced by parity(140 and 169 sows representing parity 1 to 2[P1-2]and 3 to 9[P3+],respectively)and assigned within parity to a 2×2 factorial arrangement.Factors included essential fatty acid(EFA)supplementation(control diets containing 1.2%linoleic and 0.15%α-linolenic acid or diets with 3.0%linoleic and 0.38%α-linolenic acid)and supplementation period(lactation or wean-to-breeding).Tallow(low EFA diets)or soybean oil(high EFA diets)were included at 4%in sorghum-soybean meal-wheat middlings-based diets to attain targeted EFA levels.Results High levels of EFA fed during lactation had no effect on feed intake or litter performance,but increased subsequent farrowing rate(P=0.027;82.1%vs.70.4%),tended to reduce the proportion of sows removed(P=0.070;12.4%vs.20.8%),decreased the number of total pigs born in the following litter(P=0.072;15.3 vs.16.2),and increased total pigs born alive per 100 sows weaned(P=0.062;1,122 vs.974),regardless of sow parity.Young sows(P1-2)consuming the high EFA diet during lactation displayed a shorter wean-to-estrus interval(P=0.035;4.2 vs.4.6),but P3+sows were unaffected.Increasing EFA intake for P3+sows,but not P1-2 sows,resulted in more sows bred by d 5(P=0.028;91.1%vs.81.7%)and more mummies in the subsequent litter(P=0.040;0.32 vs.0.16).Feeding increased EFA to P1-2 sows during the wean-to-breeding period decreased subsequent farrowing rate(P=0.042;72.0%vs.87.7%),and increased removal rate(P=0.003;28.8%vs.9.4%).Total pigs born alive per 100 sows weaned was reduced(P=0.007)in P1-2 sows when supplemented with EFA during wean-breeding(939 vs.1,149)but was not impacted in P3+sows(1,131 vs.982).Conclusions Supplemental EFA in lactation diets benefited subsequent reproduction of sows,regardless of parity.Increasing dietary levels of EFA during the wean-to-breeding period to younger sows negatively impacted subsequent reproduction. 展开更多
关键词 α-Linolenic acid LACTATION Linoleic acid SOWS Subsequent reproduction Wean-to-breeding
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Plasticity,Contingency,and Virtuality in the Age of Automatic Reproduction
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作者 Szymon Wróbel 《Philosophy Study》 2025年第4期135-144,共10页
In this paper,the author follows the trail of C.Malabou,Q.Meillassoux,and G.Deleuze and tries to test three philosophical concepts that seem to be particularly threatened in the era of automatic digital reproduction.T... In this paper,the author follows the trail of C.Malabou,Q.Meillassoux,and G.Deleuze and tries to test three philosophical concepts that seem to be particularly threatened in the era of automatic digital reproduction.These three concepts are plasticity(defended for many years by C.Malabou),contingency(reconstructed by Q.Meillassoux),and virtuality(developed by G.Deleuze).The main task of the text will be to reflect on which of these three concepts better protects our thinking against automation and stays faithful to the ideal of creativity.In what sense are plasticity,contingency,and the possibility of virtualization the a priori condition of any transformation,physical or intellectual,affective or conceptual metamorphosis?In what sense are these three concepts the only conditions for the survival of every living being?Would a being without contingency,plasticity,and disposition to virtualization simply be a dead being? 展开更多
关键词 automatic society CONTINGENCY PLASTICITY technical reproduction VIRTUALIZATION
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Research and development of the pulse acquisition system and the pulse biomimetic reproduction system
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作者 YI Kai MA Yunjing +2 位作者 GUO Shen LIU Heng XU Bin 《Journal of Traditional Chinese Medicine》 2025年第1期213-220,共8页
The paper is an introduction to the front-end pulse acquisition and the back-end pulse biomimetic reproduction system.This system is capable of faithfully replicating the complete pulse waveform collected at the front... The paper is an introduction to the front-end pulse acquisition and the back-end pulse biomimetic reproduction system.This system is capable of faithfully replicating the complete pulse waveform collected at the front end.Traditional Chinese Medicine(TCM)practitioners analyze and diagnose the pulse patterns at the replication end.Meanwhile,the obtained pulse waveforms are analyzed and learnt by a neural network based on key diagnostic points in TCM pulse taking,which enables the determination of the corresponding relationships between different pulse waveforms and various pulse patterns in TCM pulse taking.With the support of clinical samples,an auxiliary diagnostic system for TCM pulse patterns ensures the accuracy of pulse pattern replication. 展开更多
关键词 pulse taking medicine Chinese traditional pulse acquisition system pulse biomimetic reproduction system
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The Limitations of Social Reproduction Theory in Explaining Social Unpaid Work in the Global South
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作者 Yuqian Liu 《Journal of Contemporary Educational Research》 2025年第1期176-179,共4页
This paper defines and explores the concept of social reproduction work,highlighting its significance and the fact that women are its primary contributors.It identifies key social issues faced by social reproduction w... This paper defines and explores the concept of social reproduction work,highlighting its significance and the fact that women are its primary contributors.It identifies key social issues faced by social reproduction workers,including marginalization,neglect,and unequal access to resources.Additionally,the study examines the primary challenges encountered by these workers:the lack of direct economic benefits,difficulty in balancing work and family responsibilities,and the significant physical and mental strain associated with unpaid labor.Using the theoretical framework of the capitalist economic system,the paper delves into the root causes of the caregiving crisis.Furthermore,it critiques the applicability of reproduction work theories in explaining unpaid care work in the Global South.Three key limitations are outlined:the neglect of informal economic systems in the Global South,persistent gender inequality,and the dynamic nature of global economic migration. 展开更多
关键词 SOCIOLOGY Social reproduction Care work
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Practice and hygiene of adolescent reproduction health in agricultural area:a qualitative study
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作者 Tantut Susanto Ira Rahmawati +4 位作者 Raudlatul Jannah Pratiwi Puspitho Andini Nuning Dwi Merina Wahyuni Fauziah Alice Yuen Loke 《Frontiers of Nursing》 2025年第1期27-36,共10页
Objective: Adolescent reproduction health (ARH) differs greatly based on religions, religious norms, culture, and ethnicities in the Indonesian context. The value of local wisdom was considered too binding, traditiona... Objective: Adolescent reproduction health (ARH) differs greatly based on religions, religious norms, culture, and ethnicities in the Indonesian context. The value of local wisdom was considered too binding, traditional, and outdated, particularly on ARH in agricultural areas. The purpose of the study was to identify the problems, challenges, and needs, specifically for ARH, in the agricultural area of Indonesia. Methods: A qualitative study was performed among 41 communities, including 28 village officials (VOs), 9 community health volunteers (CHVs), and 9 adolescents. The data were collected through in-depth interviews and FGD. An thematic analysis was used to describe the phenomena. Results: This research obtained results regarding ARH in terms of communication patterns, daily behavior, reproductive practices, and hygiene of adolescent reproductive organs, especially in agricultural areas. Conclusions: The differences in the perspective of ARH are influenced by environment, parental roles, religion, ethnicity, and knowledge. 展开更多
关键词 ADOLESCENT local wisdom reproductive health practice hygiene AGRICULTURAL
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A narrative review of spermbots in assisted reproduction:Integrating AI for enhanced fertility outcomes and future innovations
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作者 Neeraj Vishwakarma Nancy Nair +1 位作者 Charu Pareek Namrata Choudhary 《Asian pacific Journal of Reproduction》 2025年第3期99-104,共6页
Sperm-structure-integrating nanodecorated microrobots have shown promise in medicine delivery and infertility treatment.A variety of spermbots use cutting-edge nanomaterials and 3D printing technology to enhance their... Sperm-structure-integrating nanodecorated microrobots have shown promise in medicine delivery and infertility treatment.A variety of spermbots use cutting-edge nanomaterials and 3D printing technology to enhance their functioning,such as biomimetic sperms and flagellate microorganisms.The success rates of assisted reproductive technology techniques like in vitro fertilisation(IVF)and intracytoplasmic sperm injection(ICSI)may increase as a result of these developments.Furthermore,the incorporation of artificial intelligence(AI)into spermbots has the potential to optimize reproductive therapies by reducing inherited illnesses through genetic screening and editing.However,before the widespread implementation of spermbots in clinical practice,several critical aspects must be addressed.Thorough investigations into biocompatibility,ethical considerations,and long-term safety are necessary to ensure that these technologies are safe and effective for in vivo applications. 展开更多
关键词 Spermbots Micro robotics Artificial intelligence(AI) Assisted reproductive technology(ART) Intracytoplasmic sperm injection(ICSI) Male infertility
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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 被引量:1
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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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Hepatitis B virus infection, infertility, and assisted reproduction
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作者 Lingjian ZHANG Fangfang ZHANG +1 位作者 Zhiyuan MA Jie JIN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2024年第8期672-685,共14页
Background:Hepatitis B virus(HBV)is one of the most widespread viruses worldwide and a major cause of hepatitis,cirrhosis,and hepatocellular carcinoma.Previous studies have revealed the impacts of HBV infection on fer... Background:Hepatitis B virus(HBV)is one of the most widespread viruses worldwide and a major cause of hepatitis,cirrhosis,and hepatocellular carcinoma.Previous studies have revealed the impacts of HBV infection on fertility.An increasing number of infertile couples with chronic hepatitis B(CHB)virus infection choose assisted reproductive technology(ART)to meet their fertility needs.Despite the high prevalence of HBV,the effects of HBV infection on assisted reproduction treatment remain limited and contradictory.Objective:The aim of this study was to provide a comprehensive overview of the effect of HBV infection on fertility and discuss its effects on pregnancy outcomes,vertical transmission,pregnancy complications,and viral activity during ART treatment.Methods:We conducted a literature search in PubMed for studies on HBV infection and ART published from 1996 to 2022.Results:HBV infection negatively affected fertility in both males and females.Existing research shows that HBV infection may increase the risk of pregnancy complications in couples undergoing assisted reproduction treatment.The impact of HBV infection on the pregnancy outcomes of ART is still controversial.Current evidence does not support that ART increases the risk of vertical transmission of HBV,while relevant studies are limited.With the development of ART,the risk of HBV reactivation(HBVr)is increasing,especially due to the wide application of immunosuppressive therapy.Conclusions:Regular HBV infection screening and HBVr risk stratification and management are essential to prevent HBVr during ART.The determination of optimal strategy and timing of prophylactic anti-HBV therapy during ART still needs further investigation. 展开更多
关键词 Assisted reproductive technology(ART) Hepatitis B virus(HBV) Immunosuppressive agent PREGNANCY
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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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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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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:19
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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:22
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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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