期刊文献+
共找到457篇文章
< 1 2 23 >
每页显示 20 50 100
Ozone Emitted During Copying Process-A Potential Cause of Pathological Oxidative Stress and Potential Oxidative Damage in the Bodies of Operators 被引量:12
1
作者 JUN-FUZHOU WEI-WEICHEN GUI-ZHONGTONG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2003年第2期95-104,共10页
To estimate the impact of copying on the indoor air quality, and to investigate whether ozone emitted during such a process induces pathological oxidative stress and potential oxidative damage in the bodies of operato... To estimate the impact of copying on the indoor air quality, and to investigate whether ozone emitted during such a process induces pathological oxidative stress and potential oxidative damage in the bodies of operators. Methods 67 copying operators (CO) and 67 healthy volunteers (HV) were enrolled in a random control study, in which levels of lipoperoxide (LPO) in plasma and erythrocytes, and levels of vitamin C (VC), vitamin E (VE) and b-carotene (b-CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined by spectrophotometric methods. Results Compared with the HV group, the average values of LPO in plasma and erythrocytes in the CO group were significantly increased (P<0.0001), while those of VC, VE and b-CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the CO group were significantly decreased (P<0.0001). Pearson product-moment correlation analysis showed that with increase of ozone level in copying sites and duration of exposure to ozone, the values of LPO in plasma and erythrocytes in the bodies of operators were gradually increased,while those of VC, VE, b-CAR, SOD, CAT and GPX were decreased in the same manner. Odds ratio (OR) of risk of biochemical parameters reflecting potential oxidative damage of the copying operators ranged from 4.440 to 13.516, and 95 % CI of OR was from 2.113 to 34.061. Reliability coefficient () of the biochemical parameters used to reflect the potential oxidative damage of the operators was 0.8156, standardized item =0.9929, P<0.0001. Conclusion Findings in the present study suggest that there exist a series of free radical chain reactions and pathological oxidative stress induced by high dose ozone in the operators, thereby causing potential oxidative and lipoperoxidative damages in their bodies. 展开更多
关键词 OZONE Oxidation LIPOPEROXIDATION Antioxidant Antioxidase Oxidative stress Oxidative damage copying copying operators Copier
在线阅读 下载PDF
Mate-choice copying: Status quo and where to go 被引量:4
2
作者 Klaudia WITTE Nina KNIEL Ilka Maria KURECK 《Current Zoology》 SCIE CAS CSCD 2015年第6期1073-1081,共9页
Mate-choice copying is a fascinating and widespread mate-choice strategy. Individuals gather public information about potential mates by observing others during sexual interactions and choose or reject the same indivi... Mate-choice copying is a fascinating and widespread mate-choice strategy. Individuals gather public information about potential mates by observing others during sexual interactions and choose or reject the same individual as a mate as the observed individual did before. The influence of copying behavior on an individual's mate choice can be so strong that socially acquired information can override genetically based preferences for certain phenotypes. Thus, mate-choice copying enforces dy- namic processes in sexual selection. Here, we review the current state of research on mate-choice copying and focus on sex-specific aspects. We present evidence that mate-choice copying can support the evolution of novel sexual ornaments, and we discuss potential costs of mate-choice copying when public information is not reliable. Moreover, we discuss the conflict faced by males that copy since mate-choice copying increases sperm competition. In conclusion we suggest interesting topics for future research in mate-choice copying . 展开更多
关键词 Mate-choice copying Public information Audience effect Sperm competition Novel ornaments
原文传递
STUDY ON COPYING QUALITY IN CONTOUR GRINDING
3
作者 Wang Wanshan Wang Bo +1 位作者 Lu Shubin Shan Ruilan(Northeastern University)Guo Changsheng(University of Massachusetts, U .S.A.) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1995年第1期47-50,共17页
A criterion is proposed to the feasibility on radial copying grinding, i.e.the pressure angleapplying to a point on the workpiece contour to be profiled should be smaller than its angle limit.Therefore, the expression... A criterion is proposed to the feasibility on radial copying grinding, i.e.the pressure angleapplying to a point on the workpiece contour to be profiled should be smaller than its angle limit.Therefore, the expressions of the angle applying to copying grinding and the angle limit to copyingmechanism are derived, with the measures taken for the quality improvement of copying movementin contour grinding discussed. 展开更多
关键词 copying grinding Pressure angle in copying Angle limit
全文增补中
Demonstrating mate choice copying in spiders requires further research
4
作者 R.Tucker GILMAN Kasey FOWLER-FINN Eileen A.HEBETS 《Current Zoology》 SCIE CAS CSCD 2020年第2期215-216,共2页
Mate choice copying-when individuals learn to prefer mates or mate types that have been chosen by others-can influence trait evo-lution and speciation(Varela et al.2018;Dion et al.2019).Most examples of mate choice co... Mate choice copying-when individuals learn to prefer mates or mate types that have been chosen by others-can influence trait evo-lution and speciation(Varela et al.2018;Dion et al.2019).Most examples of mate choice copying are from fish,birds,and mammals including humans(Varela et al.2018).However,2 invertebrate examples-fruit flies and wolf spiders-have been used to argue that the phenomenon may be phylogenetically widespread,and perhaps the rule rather than the exception in nature(Varela et al.2018).Here,we revisit the evidence for mate choice copying in wolf spiders(Fowler-Fimn et al.2015)in light of new data(Gilman et al.2018).Then,we discuss why mate choice copying is a phenomenon that is likely to occur in wolf spiders,and why this deserves attention. 展开更多
关键词 invertebrates MATE CHOICE copying SCHIZOCOSA sexual selection SPECIATION spiders
原文传递
Entanglement Preserving in Quantum Copying of Three-Qubit Entangled State
5
作者 TONG Zhao-Yang KUANG Le-Man 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第11期541-546,共6页
We study the degree to which quantum entanglement survives when a three-qubit entangled state iscopied by using local and non-local processes, respectively, and investigate iterating quantum copyingfor the three-qubit... We study the degree to which quantum entanglement survives when a three-qubit entangled state iscopied by using local and non-local processes, respectively, and investigate iterating quantum copyingfor the three-qubitsystem. There may exist inter-three-qubit entanglement and inter-two-qubit entanglement for the three-qubit system.We show that both local and non-local copying processes degrade quantum entanglement in the three-particle systemdue to a residual correlation between the copied output and the copying machine. We also show that the inter-two-qubitentanglement is preserved better than the inter-three-qubit entanglement in the local cloning process. We find thatnon-local cloning is much more efficient than the local copying for broadcasting entanglement, and output state vianon-local cloning exhibits the fidelity better than local cloning. 展开更多
关键词 ENTANGLED states QUANTUM entanglement QUANTUM copying
在线阅读 下载PDF
Entanglement Preserving in Quantum Copying of Three-Qubit Entangled State
6
作者 TONGZhao-Yang KUANGLe-Man 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第5期541-546,共6页
We study the degree to which quantum entanglement survives when a three-qubit entangled state iscopied by using local and non-local processes, respectively, and investigate iterating quantum copyingfor the three-qubit... We study the degree to which quantum entanglement survives when a three-qubit entangled state iscopied by using local and non-local processes, respectively, and investigate iterating quantum copyingfor the three-qubitsystem. There may exist inter-three-qubit entanglement and inter-two-qubit entanglement for the three-qubit system.We show that both local and non-local copying processes degrade quantum entanglement in the three-particle systemdue to a residual correlation between the copied output and the copying machine. We also show that the inter-two-qubitentanglement is preserved better than the inter-three-qubit entanglement in the local cloning process. We find thatnon-local cloning is much more efficient than the local copying for broadcasting entanglement, and output state vianon-local cloning exhibits the fidelity better than local cloning. 展开更多
关键词 entangled states quantum entanglement quantum copying
在线阅读 下载PDF
Motion-copying method with symbol sequence-based phase switch control for intelligent optical manufacturing
7
作者 Yutang Wang Dapeng Tian +2 位作者 Haixiang Hu Yan Li Shiquan Ni 《Light(Advanced Manufacturing)》 2024年第2期1-13,共13页
Implementation of robot-based motion control in optical machining demonstrably enhances the machining quality.The introduction of motion-copying method enables learning and replicating manipulation from experienced te... Implementation of robot-based motion control in optical machining demonstrably enhances the machining quality.The introduction of motion-copying method enables learning and replicating manipulation from experienced technicians.Nevertheless,the location uncertainties of objects and frequent switching of manipulated spaces in practical applications impose constraints on their further advancement.To address this issue,a motion-copying system with a symbol-sequence-based phase switch control(SSPSC)scheme was developed by transferring the operating skills and intelligence of technicians to mechanisms.The manipulation process is decomposed,symbolised,rearranged,and reproduced according to the manufacturing characteristics regardless of the change in object location.A force-sensorless adaptive sliding-mode-assisted reaction force observer(ASMARFOB),wherein a novel dual-layer adaptive law was designed for high-performance fine force sensing,was established.The uniformly ultimate boundedness(UUB)of the ASMARFOB is guaranteed based on the Lyapunov stability theory,and the switching stability of the SSPSC was examined.Validation simulations and experiments demonstrated that the proposed method enables better motion reproduction with high consistency and adaptability.The findings of this study can provide effective theoretical and practical guidance for high-precision intelligent optical manufacturing. 展开更多
关键词 Intelligent optical manufacturing Motion copy Uncertain environments Phase switch control Reaction force observer
原文传递
Single-nucleotide polymorphisms and copy number variations drive adaptive evolution to freezing stress in a subtropical evergreen broadleaved tree:Hexaploid wild Camellia oleifera 被引量:1
8
作者 Haoxing Xie Kaifeng Xing +3 位作者 Jun Zhou Yao Zhao Jian Zhang Jun Rong 《Plant Diversity》 2025年第2期214-228,共15页
Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wil... Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wild C.oleifera can serve as a case for studying the molecular bases of adaptive evolution to freezing stress.Here,47 wild C.oleifera from 11 natural distribution sites in China and 4 relative species of C.oleifera were selected for genome sequencing.“Min Temperature of Coldest Month”(BIO6)had the highest comprehensive contribution to wild C.oleifera distribution.The population genetic structure of wild C.oleifera could be divided into two groups:in cold winter(BIO6≤0℃)and warm winter(BIO6>0℃)areas.Wild C.oleifera in cold winter areas might have experienced stronger selection pressures and population bottlenecks with lower N_(e) than those in warm winter areas.155 singlenucleotide polymorphisms(SNPs)were significantly correlated with the key bioclimatic variables(106 SNPs significantly correlated with BIO6).Twenty key SNPs and 15 key copy number variation regions(CNVRs)were found with genotype differentiation>50%between the two groups of wild C.oleifera.Key SNPs in cis-regulatory elements might affect the expression of key genes associated with freezing tolerance,and they were also found within a CNVR suggesting interactions between them.Some key CNVRs in the exon regions were closely related to the differentially expressed genes under freezing stress.The findings suggest that rich SNPs and CNVRs in polyploid trees may contribute to the adaptive evolution to freezing stress. 展开更多
关键词 Adaptive evolution Camellia oleifera Copy number variations Freezing stress POLYPLOID Single-nucleotide polymorphisms
在线阅读 下载PDF
Hua Shou and his Elaboration of the Fourteen Meridians (Shi Si Jing Fa Hui)
9
作者 Yongxuan Liang Hongmei Kaneko 《Journal of Traditional Chinese Medical Sciences》 2025年第4期445-446,共2页
Hua Shou(1304-1386)styled himself Ying Ning Sheng.He was also known as Hua Boren.His ancestral home was in Xiang Town,Xu Prefecture(present Xuchang,Henan province).His birth place was Yizhen,Jiangsu province.Later he ... Hua Shou(1304-1386)styled himself Ying Ning Sheng.He was also known as Hua Boren.His ancestral home was in Xiang Town,Xu Prefecture(present Xuchang,Henan province).His birth place was Yizhen,Jiangsu province.Later he moved to Yuyao,Zhejiang province.He was one of the distinguished practitioners of the late Yuan and early Ming dynasties.His writings include Elaboration of the Fourteen Meridians(Shi Si Jing Fa Hui),Notes on Handwritten Copy of Basic Questions(Du Su Wen Chao),The Essentials for Physicians(Zhen Jia Shu Yao). 展开更多
关键词 handwritten copy basic questions du Fourteen Meridians Notes Handwritten Copy elaboration fourteen meridians shi Shi Si Jing Fa Hui hua borenhis Essentials Physicians Hua Shou
暂未订购
Prolonged passive vibration of Achilles and patellar tendons decreases effort perception during subsequent cycling tasks
10
作者 Florian Marchand Benjamin Pageaux +1 位作者 Nicolas Forestier Florian Monjo 《Journal of Sport and Health Science》 2025年第5期124-133,共10页
Background:The perception of effort is a key determinant of endurance performance and a barrier to physical activity in inactive populations.From a neurophysiological viewpoint,effort perception is thought to arise fr... Background:The perception of effort is a key determinant of endurance performance and a barrier to physical activity in inactive populations.From a neurophysiological viewpoint,effort perception is thought to arise from the brain processing of an efference copy of the motor command in sensory areas.However,recent research suggests that feedback from muscle spindles plays a significant role in this perception.In this study,tendon vibration protocols were employed to attenuate sensory feedback during subsequent cycling exercises.The aim was to assess whether vibration would increase cycling power output,muscle activation,and heart rate at fixed perceived effort intensities.Methods:Fifteen healthy young participants completed 2 experimental visits(vibration and sham).In each visit,participants performed two 3-min cycling bouts,1 at a moderate perceived effort intensity and 1 at a strong perceived effort intensity,before(pre)and after(post)an actual or a sham vibration protocol.Vibration was applied bilaterally on the patellar and Achilles tendons for 10 min.Power output,heart rate,and vastus lateralis electromyography(VL EMG)were recorded and averaged for each bout.Absolute values as well as relative change(%)between pre and post conditions were compared across sham and vibration conditions.Results:At moderate perceived effort,power output,heart rate,and VL EMG increased post-vibration compared to pre-vibration(p<0.05),while no difference was observed in the sham condition.At strong perceived effort,power output and VL EMG decreased post-sham(p<0.05)but remained unchanged post-vibration.Moreover,the relative change between pre and post conditions was significantly higher in the vibration conditions compared to the sham condition for all variables.Conclusion:This study shows that tendon vibration reduces effort perception during subsequent cycling bouts.This effect is likely a consequence of vibration-induced reduction in muscle spindle reafferent signaling to the brain,but this mechanism remains to be further elucidated.From an applied perspective,these findings highlight tendon vibration as a promising tool for enhancing physical activity engagement. 展开更多
关键词 Efference copy Muscle spindles PACING Physical activity Sense of effort
在线阅读 下载PDF
Linking rhizosphere bacterial life-history strategies with wheat growth under drought stress
11
作者 Yanshuo Pan Binhui Liu +7 位作者 Shan Zhuang Hongzhe Wang Yanjie Qi Jieyin Chen Didier Lesueur Liang Xiao Yuzhong Li Dongfei Han 《Soil Ecology Letters》 2025年第3期307-318,共12页
The metabolic complexity of microorganisms can be simplified by classifying them into r-strategists and K-strategists.However,their associations with plant growth during drought remain largely unclear.Herein,we used t... The metabolic complexity of microorganisms can be simplified by classifying them into r-strategists and K-strategists.However,their associations with plant growth during drought remain largely unclear.Herein,we used the ribosomal RNA gene operon(rrn)copy number to characterize bacterial life-history strategies,with increased rrn copy numbers suggesting a shift from K-to r-strategies.We generated a series of bacterial communities with increased rrn copy numbers in rhizosphere.Drought decreased rhizosphere bacterial rrn copy numbers,rather than in root,indicating a prevalence of K-strategies during drought stress in rhizosphere.The rrn copy numbers of rhizosphere communities were negatively related to wheat growth during drought,while no significant associations were observed in control treatment.Rhizosphere bacterial communities with higher rrn copy numbers exhibited less community dissimilarity and tended to be more stable.Moreover,the abundance of most predicted functions decreased with rrn copy numbers in drought-stressed rhizosphere.Co-occurrence network analysis indicated that increased rrn copy numbers in rhizosphere community improved the proportion of negative to positive cohesion,implying more stable networks.Our findings bring up innovative knowledge about the relationships between microbial life-history strategies,communities and plant growth,and highlights the importance of plant-microorganism interactions for plant growth during stress. 展开更多
关键词 life-history strategies rrn copy numbers co-occurrence network plant growth drought stress
原文传递
Biological and translational attributes of mitochondrial DNA copy number:Laboratory perspective to clinical relevance
12
作者 Deepak Parchwani Ragini Singh Digisha Patel 《World Journal of Methodology》 2025年第3期38-55,共18页
The mitochondrial DNA copy number(mtDNAcn)plays a vital role in cellular energy metabolism and mitochondrial health.As mitochondria are responsible for adenosine triphosphate production through oxidative phosphorylati... The mitochondrial DNA copy number(mtDNAcn)plays a vital role in cellular energy metabolism and mitochondrial health.As mitochondria are responsible for adenosine triphosphate production through oxidative phosphorylation,maintaining an appropriate mtDNAcn level is vital for the overall cellular function.Alterations in mtDNAcn have been linked to various diseases,including neurodegenerative disorders,metabolic conditions,and cancers,making it an important biomarker for understanding the disease pathogenesis.The accurate estimation of mtDNAcn is essential for clinical applications.Quantitative polymerase chain reaction and next-generation sequencing are commonly employed techniques with distinct advantages and limitations.Clinically,mtDNAcn serves as a valuable indicator for early diagnosis,disease progression,and treatment response.For instance,in oncology,elevated mtDNAcn levels in blood samples are associated with tumor aggressiveness and can aid in monitoring treatment efficacy.In neurodegenerative diseases such as Alzheimer’s and Parkinson’s,altered mtDNAcn patterns provide insights into disease mechanisms and progression.Understanding and estimating mtDNAcn are critical for advancing diagnostic and therapeutic strategies in various medical fields.As research continues to uncover the implications of mtDNAcn alterations,its potential as a clinical biomarker is likely to expand,thereby enhancing our ability to diagnose and manage complex diseases. 展开更多
关键词 Mitochondrial DNA copy number Mitochondrial DNA Quantitative polymerase chain reaction Cancer Neurodegenerative disease AGING
暂未订购
Health risks of rare earth elements exposure:Impact on mitochondrial DNA copy number and micronucleus frequency
13
作者 Shiyi Hong Yali Zhang +6 位作者 Qiaojian Zhang Zekang Su Guiping Hu Li Wang Shanfa Yu Xiaojun Zhu Guang Jia 《Journal of Environmental Sciences》 2025年第5期150-160,共11页
Toxic effects in terms of mitochondria and hereditary substances have been characterized in vitro for individual rare earth elements,while,the joint effects of mixed elements exposure in the population remain ambiguou... Toxic effects in terms of mitochondria and hereditary substances have been characterized in vitro for individual rare earth elements,while,the joint effects of mixed elements exposure in the population remain ambiguous.Based on the Occupational Chromate Exposure Dynamic Cohort of China,this study investigated the relationship between 15 blood rare earth elements(cerium,dysprosium,erbium,europium,gadolinium,holmium,lanthanum,lutetium,neodymium,praseodymium,samarium,terbium,thulium,yttrium,and ytterbium)and mitochondrial DNA copy number(MtDNACN)as well as peripheral blood lymphocyte micronucleus frequency(MNF).The elastic net was used to select elements highly correlated with effect indicators,whose dose-response relationships were further illustrated by restricted cubic splines.Bayesian kernel regressionwas employed to explore the combined effects of elements and the contributions of single element.The results showed that most rare earth elementswere positively correlatedwith effect indicators,with yttrium showing the strongest association(β(95%CI):0.139(0.1089–0.189)for MtDNACN,0.937(0.345–1.684)for MNF).In the mixed exposure model,with the exposure level fixed at the 50th percentile as the reference,the effect estimates on MtDNACN and MNF increased by 0.228 and 0.598 units,respectively,at the 75th percentile.The single effect analysis implied that yttrium,lanthanum and terbium contributed the most to the elevation of MtDNACN,while yttrium posed the highest risk for genetic damage,accordingly,we provided recommendations to prioritize these elements of concern.In addition,we observed a chief mediating effect of MtDNACN on the elevation of MNF caused by lanthanum,whereas further mechanistic exploration is required to confirm this finding. 展开更多
关键词 Rare earth elements Mitochondrial DNA copy number Micronucleus frequency Mixed effect
原文传递
Unraveling the missing heritability of amyotrophic lateral sclerosis:Should we focus more on copy number variations?
14
作者 Maria Guarnaccia Valentina La Cognata +2 位作者 Giulia Gentile Giovanna Morello Sebastiano Cavallaro 《Neural Regeneration Research》 2026年第5期1997-1998,共2页
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive degeneration of upper and lower motor neurons in the brainstem and spinal cord,leading to muscle weakness,para... Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive degeneration of upper and lower motor neurons in the brainstem and spinal cord,leading to muscle weakness,paralysis,and respiratory failure (Morgan and Orrell,2016). 展开更多
关键词 degeneration upper lower motor neurons unraveling neurodegenerative disorder missing heritability amyotrophic lateral sclerosis copy number variations
暂未订购
Copying La Tomatina
15
《Beijing Review》 2009年第33期46-47,共2页
In order to celebrate its second anniversary,a shopping center in Guiyang,capital of southwest China’s Guizhou Province,organized a tomato fight on July 20.The idea was based on the famed tomato festivalin Spain.
关键词 copying La Tomatina LA
原文传递
Genome-wide investigation to assess copy number variants in the Italian local chicken population 被引量:3
16
作者 Filippo Cendron Martino Cassandro Mauro Penasa 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期563-577,共15页
Background Copy number variants(CNV)hold significant functional and evolutionary importance.Numerous ongoing CNV studies aim to elucidate the etiology of human diseases and gain insights into the population structure ... Background Copy number variants(CNV)hold significant functional and evolutionary importance.Numerous ongoing CNV studies aim to elucidate the etiology of human diseases and gain insights into the population structure of livestock.High-density chips have enabled the detection of CNV with increased resolution,leading to the identification of even small CNV.This study aimed to identify CNV in local Italian chicken breeds and investigate their distribution across the genome.Results Copy number variants were mainly distributed across the first six chromosomes and primarily associated with loss type CNV.The majority of CNV in the investigated breeds were of types 0 and 1,and the minimum length of CNV was significantly larger than that reported in previous studies.Interestingly,a high proportion of the length of chromosome 16 was covered by copy number variation regions(CNVR),with the major histocompatibility complex being the likely cause.Among the genes identified within CNVR,only those present in at least five animals across breeds(n=95)were discussed to reduce the focus on redundant CNV.Some of these genes have been associated to functional traits in chickens.Notably,several CNVR on different chromosomes harbor genes related to muscle development,tissue-specific biological processes,heat stress resistance,and immune response.Quantitative trait loci(QTL)were also analyzed to investigate potential overlapping with the identified CNVR:54 out of the 95 gene-containing regions overlapped with 428 QTL associated to body weight and size,carcass characteristics,egg production,egg components,fat deposition,and feed intake.Conclusions The genomic phenomena reported in this study that can cause changes in the distribution of CNV within the genome over time and the comparison of these differences in CNVR of the local chicken breeds could help in preserving these genetic resources. 展开更多
关键词 CHICKEN Copy number variant CONSERVATION Local breed SNP
在线阅读 下载PDF
Sperm function, mitochondrial activity and in vivo fertility are associated to their mitochondrial DNA content in pigs 被引量:2
17
作者 Marc Llavanera Yentel Mateo‑Otero +2 位作者 Estel Vinolas‑Vergés Sergi Bonet Marc Yeste 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1550-1558,共9页
Background Despite their low abundance in sperm, mitochondria have diverse functions in this cell type, includ-ing energy production, signalling and calcium regulation. In humans, sperm mitochondrial DNA content(mtDNA... Background Despite their low abundance in sperm, mitochondria have diverse functions in this cell type, includ-ing energy production, signalling and calcium regulation. In humans, sperm mitochondrial DNA content(mtDNAc) has been reported to be negatively linked to sperm function and fertility. Yet, the association between mtDNAc and sperm function in livestock remains unexplored. For this reason, this study aimed to shed some light on the link between mtDNAc and sperm function and fertilising potential in pigs. A qPCR method for mtDNAc quantification was optimised for pig sperm, and the association of this parameter with sperm motility, kinematics, mitochondrial activity, and fertility was subsequently interrogated.Results First, the q PCR method was found to be sensitive and efficient for mtDNAc quantification in pig sperm. By using this technique, mtDNAc was observed to be associated to sperm motility, mitochondrial activity and in vivo, but not in vitro, fertility outcomes. Specifically, sperm with low mtDNAc were seen to exhibit greater motility but decreased mitochondrial activity and intracellular reactive oxygen species. Interestingly, samples with lower mtD-NAc showed higher conception and farrowing rates, but similar in vitro fertilisation rates and embryo development, when compared to those with greater mtDNAc.Conclusions These findings enrich our comprehension of the association of mtDNAc with sperm biology, and lay the foundation for future research into employing this parameter as a molecular predictor for sperm function and fer-tility in livestock. 展开更多
关键词 FERTILITY MITOCHONDRIA MOTILITY mtDNA copy number qPCR SPERM
在线阅读 下载PDF
Single-crystallization of electrolytic copper foils 被引量:1
18
作者 Xingguang Li Mengze Zhao +13 位作者 Quanlin Guo Chong Zhao Mingchao Ding Dingxin Zou Zhiqiang Ding Zhiqiang Zhang Menglin He Kehai Liu Muhong Wu Zhihong Zhang Enge Wang Ying Fu Kaihui Liu Zhibin Zhang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第9期112-118,共7页
Depending on the production process,copper(Cu)foils can be classified into two types,i.e.,rolled copper(r-Cu)foils and electrolytic copper(e-Cu)foils.Owing to their high electrical conductivity and ductility at low co... Depending on the production process,copper(Cu)foils can be classified into two types,i.e.,rolled copper(r-Cu)foils and electrolytic copper(e-Cu)foils.Owing to their high electrical conductivity and ductility at low cost,e-Cu foils are employed extensively in modern industries and account for more than 98%of the Cu foil market share.However,industrial e-Cu foils have never been single-crystallized due to their high density of grain boundaries,various grain orientations and vast impurities originating from the electrochemical deposition process.Here,we report a methodology of transforming industrial e-Cu foils into single crystals by facet copy from a single-crystal template.Different facets of both low and high indices are successfully produced,and the thickness of the single crystal can reach 500μm.Crystallographic characterizations directly recognized the single-crystal copy process,confirming the complete assimilation impact from the template.The obtained single-crystal e-Cu foils exhibit remarkably improved ductility(elongation-to-fracture of 105%vs.25%),fatigue performance(the average numbers of cycles to failure of 1600 vs.200)and electrical property(electrical conductivity of 102.6%of the international annealed copper standard(IACS)vs.98.5%)than original ones.This work opens up a new avenue for the preparation of single-crystal e-Cu foils and may expand their applications in high-speed,flexible,and wearable devices. 展开更多
关键词 Electrolytic copper foil Single-crystallization Facet copy Grain growth Mechanical property
原文传递
Clinical manifestations and the prenatal diagnosis of trisomy 7 mosaicism:Two case reports 被引量:1
19
作者 Fei Hou Yan Li Hua Jin 《World Journal of Clinical Cases》 SCIE 2024年第8期1544-1548,共5页
BACKGROUND The clinical manifestations of trisomy 7 mosaicism are diverse and nonspecific,so prenatal diagnosis is very difficult.CASE SUMMARY Two pregnant women with abnormal prenatal screening results were included.... BACKGROUND The clinical manifestations of trisomy 7 mosaicism are diverse and nonspecific,so prenatal diagnosis is very difficult.CASE SUMMARY Two pregnant women with abnormal prenatal screening results were included.One was a 22-year-old woman(G1P0).At 31st week of gestation,ultrasound revealed that the posterior horn of the left lateral ventricle was 10 mm and the right renal pelvis had a separation of 7 mm.The other pregnant woman was 33 years old(G2P1L1A0),and her fetus was found to have a cardiac malformation at the 24th week of gestation.Copy number variation sequencing,whole-exome sequencing and karyotype analysis were carried out after amniocentesis,and both fetuses were diagnosed with trisomy 7 mosaicism.After parental counseling,one woman continued the pregnancy,and the other woman terminated the pregnancy.CONCLUSION In trisomy 7 mosaicism,the low proportion of trisomy does not lead to abortion,but can result in abnormal fetal development,which can be detected via ultrasound.Therefore,clinicians need to pay more attention to various aspects of fetal growth and development,combining with imaging,cellular,molecular genetics and other methods to perform comprehensive evaluations of fetuses to provide more reliable genetic counseling for pregnant women. 展开更多
关键词 Trisomy 7 mosaicism Copy number variation sequencing Whole-exome sequencing Karyotype analysis Prenatal diagnosis Case report
暂未订购
Exploring the interplay of T cell receptor-V gene copy numbers and major histocompatibility complex selection pressure in avian species:Insights into immune system evolution and reproductive investment
20
作者 Lin Sun Chunhong Liang +2 位作者 Shidi Qin Ying Zhu Ke He 《Avian Research》 SCIE CSCD 2024年第4期503-511,共9页
Birds,a fascinating and diverse group occupying various habitats worldwide,exhibit a wide range of life-history traits,reproductive methods,and migratory behaviors,all of which influence their immune systems.The assoc... Birds,a fascinating and diverse group occupying various habitats worldwide,exhibit a wide range of life-history traits,reproductive methods,and migratory behaviors,all of which influence their immune systems.The association between major histocompatibility complex(MHC)genes and certain ecological factors in response to pathogen selection has been extensively studied;however,the role of the co-working molecule T cell receptor(TCR)remains poorly understood.This study aimed to analyze the copy numbers of TCR-V genes,the selection pressure(ωvalue)on MHC genes using available genomic data,and their potential ecological correlates across 93 species from 13 orders.The study was conducted using the publicly available genome data of birds.Our findings suggested that phylogeny influences the variability in TCR-V gene copy numbers and MHC selection pressure.The phylogenetic generalized least squares regression model revealed that TCR-Vαδcopy number and MHC-I selection pressure were positively associated with body mass.Clutch size was correlated with MHC selection pressure,and Migration was correlated with TCR-Vβcopy number.Further analyses revealed that the TCR-Vβcopy number was positively correlated with MHC-IIB selection pressure,while the TCR-Vγcopy number was negatively correlated with MHC-I peptide-binding region selection pressure.Our findings suggest that TCR-V diversity is significant in adaptive evolution and is related to species’life-history strategies and immunological defenses and provide valuable insights into the mechanisms underlying TCR-V gene duplication and MHC selection in avian species. 展开更多
关键词 Copy number variation Immune genes MHC selection pressure Pathogen selection TCR-V gene
在线阅读 下载PDF
上一页 1 2 23 下一页 到第
使用帮助 返回顶部