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Insulin-like Growth Factor-I (IGF-I) in Reproduction System of Female Bovine
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作者 QI Meiyu ZviRoth LIU Di 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第4期84-87,共4页
Insulin-like growth factor-I (IGF-I) plays a key role in female reproduction, because it has the effect of anti-apoptosis improving cell proliferation, transformation and differentiation. This paper reviewed the eff... Insulin-like growth factor-I (IGF-I) plays a key role in female reproduction, because it has the effect of anti-apoptosis improving cell proliferation, transformation and differentiation. This paper reviewed the effects of IGF-I on ovary, follicle growth, acquisition of oocyte competence and preimplantation embryo viability, and then summarized different points about IGF-1 for reproduction system 展开更多
关键词 IGF-1 BOVINE reproduction system OVARY follicle OOCYTE preimplantation embryo
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Unidirectional Sound Signage for Speech Frequency Range Using Multiple-Loudspeaker Reproduction System
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作者 Vecky Canisius Poekoel Koshiro Hira +1 位作者 Yoshifumi Chisaki Tsuyoshi Usagawa 《Open Journal of Acoustics》 2013年第4期120-126,共7页
Human safety is the most important issue in disaster management. Speech is a sound signal containing information that is easily and quickly understood by humans. Using speech as sound signage in emergency systems can ... Human safety is the most important issue in disaster management. Speech is a sound signal containing information that is easily and quickly understood by humans. Using speech as sound signage in emergency systems can effectively increase human safety in low or poor visibility conditions such as in smoke-filled situations. However, reflections of sound through walls, floor surfaces, and ceilings will affect clarity of speech. Unfortunately, because of the characteristics of sound reproduction systems, a single loudspeaker propagates sound waves omni-directionally at low frequencies. This paper proposes a simple multiple-loudspeaker system for reproducing sound with uni-directional characteristics. The proposed system consists mainly of a primary loudspeaker for introducing sound in the desired beam, a secondary loudspeaker for reducing gain in the undesired direction, and digital filters. An adaptive finite-impulse-response (FIR) filter is used to produce the controlling sound by implementing a filtered-x least-mean-square algorithm, and a delay filter for adjusting the time alignment of sound propagation between primary and secondary sources at the control point. Several operational conditions for illustrating real situations and reflections were considered in an anechoic chamber. Experimental results show the directivity patterns of the proposed multiple-loudspeaker system for the required conditions. In a low frequency range, the system is able to control unidirectional propagation;there is a sound beam in the desired direction and, conversely, reduction of gain in the undesired direction around the control point. 展开更多
关键词 Uni-Directional reproduction system Multiple-Loudspeaker system Adaptive Filter Propagation Low Frequency
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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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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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Patterns and drivers of plant sexual systems in the dry-hot valley region of southwestern China
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作者 Rong Ma Qi Xu +3 位作者 Yongqian Gao Deli Peng Hang Sun Bo Song 《Plant Diversity》 SCIE CAS CSCD 2024年第2期158-168,共11页
Sexual systems play important roles in angiosperm evolution and exhibit substantial variations among different floras. Thus, studying their evolution in a whole flora is crucial for understanding the formation and mai... Sexual systems play important roles in angiosperm evolution and exhibit substantial variations among different floras. Thus, studying their evolution in a whole flora is crucial for understanding the formation and maintenance of plant biodiversity and predicting its responses to environmental change. In this study, we determined the patterns of plant sexual systems and their associations with geographic elements and various life-history traits in dry-hot valley region of southwestern China, an extremely vulnerable ecosystem. Of the 3166 angiosperm species recorded in this area, 74.5% were hermaphroditic,13.5% were monoecious and 12% were dioecious, showing a high incidence of diclinous species. Diclinous species were strongly associated with tropical elements, whereas hermaphroditic species were strongly associated with temperate and cosmopolitan elements. We also found that hermaphroditism was strongly associated with showy floral displays, specialist entomophily, dry fruits and herbaceous plants.Dioecy was strongly associated with inconspicuous, pale-colored flowers, generalist entomophily, fleshy fruits, and woody plants, whereas monoecy was strongly associated with inconspicuous, pale-colored flowers, anemophily, dry fruits, and herbaceous plants. In addition, hermaphroditic species with generalist entomophily tended to flower in the dry season, whereas diclinous species with specialist entomophily tended to flower in the rainy season. However, independent of sexual systems, plants that produce dry fruits tended to flower in the rainy season and set fruits in the dry season, but the opposite pattern was found for fleshy fruit-producing plants. Our results suggest that in the dry-hot valleys, plant sexual systems are associated with geographic elements as well as various life-history traits that are sensitive to environmental change. 展开更多
关键词 Floral traits Fruit type Growth form Pollination system Reproductive phenology
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How cushion communities are maintained in alpine ecosystems: A review and case study on alpine cushion plant reproduction 被引量:5
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作者 Jianguo Chen Yanbo Li +1 位作者 Yang Yang Hang Sun 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第4期221-228,共8页
Cushion species occur in nearly all alpine environments worldwide. In past decades, the adaptive and ecosystem-engineering roles of such highly specialized life forms have been well studied. However, the adaptive stra... Cushion species occur in nearly all alpine environments worldwide. In past decades, the adaptive and ecosystem-engineering roles of such highly specialized life forms have been well studied. However, the adaptive strategies responsible for cushion species reproductive success and maintenance in severe alpine habitats remain largely unclear. In this study, we reviewed the current understanding of reproductive strategies and population persistence in alpine cushion species. We then present a preliminary case study on the sexual reproduction of Arenaria polytrichoides(Caryophyllaceae), a typical cushion species inhabiting high elevations of the Himalaya Hengduan Mountains, which is a hotspot for diversification of cushion species. Finally, we highlight the limitations of our current understanding of alpine cushion species reproduction and propose future directions for study. 展开更多
关键词 Alpine ecosystem Cushion plant Community recruitment Growth rate Life-span reproduction
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EXPERIMENT WITH ONE DIMENSIONAL DATA FOR REPRODUCTION OF ATTRACTOR STRUCTURE IN N-DIMENSIONAL SYSTEM
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作者 林振山 朱焰宇 《Journal of Tropical Meteorology》 SCIE 1997年第1期105-112,共8页
Illustrated with the Rossler and Lorenz systems, the topological structure is reproduced using univariable temporal series. The study shows that there are a number of principal vectors reproduced withone-dimensional t... Illustrated with the Rossler and Lorenz systems, the topological structure is reproduced using univariable temporal series. The study shows that there are a number of principal vectors reproduced withone-dimensional temporal series,which reflect from a certain aspect the topological structure for the system attractors. 展开更多
关键词 phase space principal VECTORS reproduction of TOPOLOGICAL STRUCTURE
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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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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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The peptide fraction of Bothrops jararaca snake venom induces toxicological effects on the male reproductive system after local envenomation in mice
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作者 CARLOS ALBERTO-SILVA ANA CAROLINA DE ARAUJO +1 位作者 RODRIGO SIMÃO BONFIM JOYCE MEIRE GILIO 《BIOCELL》 SCIE 2023年第2期289-295,共7页
Bothrops envenomation is complex and provokes prominent local tissue damage and systemic disturbances,but little is known about their effects on the male reproductive system.After intratesticular injection,the bioacti... Bothrops envenomation is complex and provokes prominent local tissue damage and systemic disturbances,but little is known about their effects on the male reproductive system.After intratesticular injection,the bioactive peptide fraction(Bj-PF)obtained from Bothrops jararaca snake venom changes the structure of different stages of the seminiferous epithelium cycle in adult mice.For the first time,we investigated whether local envenomation of Bj-PF induces toxicological effects on the male reproductive system,particularly on the seminiferous epithelium and Sertoli cells.Male adult mice were treated with 0.24 mg.kg^(-1) by intramuscular(i.m.)injection for 24 h.The testes samples were collected for morphological and morphometric evaluation.The toxicological effects of Bj-PF were also analyzed on mitochondrial metabolism and nitrite(NO2)production in 15P-1 Sertoli cell culture.Bj-PF changed the structure and function of the seminiferous epithelium,particularly the disruption of the epithelium and the presence of degenerated germ cells in the adluminal compartment,but there were no alterations in the basal compartment.Bj-PF increased the thickness of the seminiferous epithelium and decreased the lumen diameter of the tubule.Semiquantitative histological assessment of the degree of tubule degeneration revealed that Bj-PF also increased the number of hypospermatogenic tubules compared to control.Bj-PF reduced NO2 levels in 15P-1 Sertoli cells without changing the mitochondrial metabolism.Overall,the fact that Bj-PF alters the structure and function of the seminiferous epithelium suggests that bioactive peptides found in B.jararaca snake venom can have toxicological effects on the reproductive systems of affected male mice,providing new insight into the biological characteristics of snake venom and therapeutic strategies for envenomation inflammation. 展开更多
关键词 Snake venom Bothrops jararaca Reproductive toxicology Seminiferous epithelium
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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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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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Study on Breeding Practices and Reproductive Performance of Black-Head Somali Sheep under Traditional Management System: The Case of Awbarre District, Eastern Ethiopia
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作者 Abdi Abdilahi Kawnin Abdimahad +1 位作者 Abdulahi Mahamed Abdimawlid Ali 《Open Journal of Animal Sciences》 CAS 2023年第1期20-33,共14页
The study was conducted in the Awbarre district of the Fafen zone of the Somali regional state of Ethiopia. The objective of the study was to assess the breeding practices and reproductive performance of Black-head So... The study was conducted in the Awbarre district of the Fafen zone of the Somali regional state of Ethiopia. The objective of the study was to assess the breeding practices and reproductive performance of Black-head Somali sheep under a traditional management system. Purposive and simple random sampling techniques were used to select targeted kebeles and households, respectively. A total of 120 households were selected from four kebeles, each of 30 households, based on the production system and sheep population. Semi-structured questionnaires, group discussions, key informants interviews and field observations were used to generate the required data. The primary purpose of keeping sheep was for income generation, followed by saving as a future asset. The majority (89.2%) of the respondents separated male and female animals during herding. The selection criteria for breeding rams were appearance, growth, pedigree, and color while for breeding ewes were appearance, adaptability, pedigree, color, and lamb growth. The overall weaning age of Black-head Somali sheep in the study area was 3.7 months for both males & females. The castration of male sheep was common for the purpose of fattening, fattening with breeding control and breeding control as well. The castration is mainly performed during the summer and autumn and the methods of castration were both traditional and modern methods, the traditional castration method being the most important one in pastoral areas. The age of sexual maturity was 7.64 months for rams and 8.97 months for ewe’s male and female lambs in the pastoral area and 8.42 & 8.38 for rams & ewes in agro-pastoral and overall lambing interval was 11 months. On average, the ewe of Black-head Somali sheep in pastoral & agro-pastoral could produce 9.49 & 9.57 lambs, respectively in their lifetime. As the pastoralists and agro-pastoralists indicated the source of the breeding ram was their own, so the exchange of breeding ram is recommended to minimize the risk of inbreeding and further studies of on-farm performance investigation would be necessary to be carried out so as to understand the uniqueness of the breed better. 展开更多
关键词 Black-Head Somali Sheep Breeding Practice Reproductive Performance Selection Criteria
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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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Occupational,environmental and psychosocial factors impacting reproductive health of women working in manufacturing sector in India:a systematic review
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作者 Bishal Patangia Anuradha Sathiyaseelan +1 位作者 Noel Singh Dias Ashwini M 《Life Research》 2023年第2期1-9,共9页
Background:Women working in manufacturing are exposed to harmful chemicals and gases;environmental and psychosocial factors such as stress,anxiety,and burnout severely affect their reproductive health.Like physiologic... Background:Women working in manufacturing are exposed to harmful chemicals and gases;environmental and psychosocial factors such as stress,anxiety,and burnout severely affect their reproductive health.Like physiological factors,psychosocial factors equality disrupts women’s reproductive health who are working in such aversive circumstances.Method:The current study is a systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis checklist.The primary sources of articles were central databases such as SCOPUS,Web of Science,PubMed,and others.Cambridge Quality Checklist was used to measure the quality of the review articles.Result:A total of 14 articles were found eligible for the review;5 studies were on occupational health in general,3 studies addressed menstrual distress,3 studies on pregnancy,and 3 on menopausal issues.Pandemic experiences increase the health risk with the rise in food and financial insecurity among manufacturing workers.Conclusion:Psychosocial factors such as stress,anxiety,loneliness,discrimination,and depression are associated with a risk to reproductive health.The uncertainty caused by the pandemic was a major stressor for the manufacturing workers in India.The findings would represent significant challenges and factors affecting women’s reproductive health.Proper interventions and measures could be taken to regulate health risks. 展开更多
关键词 manufacturing workers psychosocial factors reproductive health WOMEN
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Utilization of online systems to promote youth participation in research:A methodological study
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作者 Marie Salem Lance Pollack +1 位作者 Alex Zepeda Kathleen P Tebb 《World Journal of Methodology》 2023年第4期210-222,共13页
BACKGROUND Online surveys can align with youth’s increased use of the internet and can be a mechanism for expanding youth participation in research.This is particularly important during the coronavirus disease 2019(C... BACKGROUND Online surveys can align with youth’s increased use of the internet and can be a mechanism for expanding youth participation in research.This is particularly important during the coronavirus disease 2019(COVID-19)pandemic,when inperson interactions are limited.However,the advantages and drawbacks of online systems used for research need to be carefully considered before utilizing such methodologies.AIM To describe and discuss the strengths and limitations of an online system developed to recruit adolescent girls for a sexual health research study and conduct a three-month follow up survey.METHODS This methodology paper examines the use of an online system to recruit and follow participants three months after their medical visit to evaluate a mobile sexual and reproductive health application,Health-E You/Salud iTuTM,for adolescent girls attending school-based health centers(SBHCs)across the United States.SBHC staff gave adolescent girls a web link to an online eligibility and consent survey.Participants were then asked to complete two online surveys(baseline and 3-month follow-up).Surveys,reminders,and incentives to complete them were distributed through short message service(SMS)text messages.Upon completing each survey,participants were also sent an email with a link to an electronic gift card as a thank-you for their participation.Barriers to implementing this system were discussed with clinicians and staff at each participating SBHC.RESULTS This online recruitment and retention system enabled participant recruitment at 26 different SBHCs in seven states across the United States.Between September 2021 and June 2022,415 adolescent girls were screened using the Qualtrics online survey platform,and 182 were eligible to participate.Of those eligible,78.0%(n=142)completed the baseline survey.Participants were racially,geographically,and linguistically diverse.Most of the participants(89.4%)were non-White,and 40.8%spoke Spanish.A total of 62.0%(n=88)completed the 3-month follow-up survey.Limitations of this system included reliance on internet access(via Wi-Fi or cell service),which was not universally available or reliable.In addition,an individual unrelated to the study obtained the survey link,filled out multiple surveys,and received multiple gift cards before the research team discovered and stopped this activity.As a result,additional security protocols were instituted.CONCLUSION Online systems for health research can increase the reach and diversity of study participants,reduce costs for research personnel time and travel,allow for continued study operation when in-person visits are limited(such as during the COVID-19 pandemic),and connect youth with research using technology.However,there are challenges and limitations to online systems,which include limited internet access,intermittent internet connection,data security concerns,and the potential for fraudulent users.These challenges should be considered prior to using online systems for research. 展开更多
关键词 Online recruitment Adolescents Sexual and reproductive health Mobile data Methodology paper Data security
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Male Reproductive System and Spermatogenesis in Homoptera(Insecta:Hemiptera) 被引量:7
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作者 田润刚 袁锋 张雅林 《Entomotaxonomia》 CSCD 北大核心 2006年第4期241-253,共13页
Morphology of the male reproductive system, chromosome behaviors during meiosis and spem tail structures in Homoptera and Heteroptera are compared in this paper. The sheathed testis is found in Fulgoroidea and Heterop... Morphology of the male reproductive system, chromosome behaviors during meiosis and spem tail structures in Homoptera and Heteroptera are compared in this paper. The sheathed testis is found in Fulgoroidea and Heteroptera, and unsheathed testis occurs in Cicadoidea, Cicadelloidea, Cercopoidea, Membracoidea, Psyloidea, Aphidoidea, Aleyrodoidea and Coccoidea. The testis also can be divide into three types by the shape of testicular follicles. The sphere-shaped type is found in Cicadoidea, Cicadelloidea, Cercopoidea, Membracoidea, Aphidoidea and Aleyrodoidea, the tube-shaped type observed in Fulgoroidea, Psyloidea and Coccoidea, and the lamella-shaped type represented by Heteroptera. It is suggested the unsheathed testis may be the primitive type in Homoptera. Meiosis can be divided into 6 type at least, i.e. 1) Cicadoid type; 2) Fulgoroid type; 3) Psyloid type; 4) Aphidoid type; 5) Aleyrodoid type; and 6) Coccoid type. At least four groups exhibit a diffuse stage during meiosis prophase l, they are Psyloidea, Fulgoroidea, Coccoidea and Heteroptera. Sperm tail structures are similar to those reported from other insects with a typical 9+9+2 axoneme except that in Aleyrodoidea and Coccoidea whose sperm tail is degenerated. 展开更多
关键词 HEMIPTERA HOMOPTERA reproductive system SPERMATOGENESIS MEIOSIS sperm structure
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