期刊文献+
共找到3,577篇文章
< 1 2 179 >
每页显示 20 50 100
Endoscopic retrograde cholangiopancreatography in pediatric and adult populations:17-year experience from Pakistan with trends,complications,and global comparison
1
作者 Noval Zakaria Muhammad U Tahseen +16 位作者 Talha S Niaz Muhammad Asim Asma Yaseen Shanil Kadir Sajida Qureshi Shahriyar Ghazanfar Aftab Leghari Muhammad A Taj Arif R Siddiqui Abeer Altaf Naseer Ahmed Areeba Raza Javeria Salman Umer B Shoaib Mehreen Siyal Abdul K Durvesh Saad K Niaz 《World Journal of Gastrointestinal Endoscopy》 2025年第11期79-89,共11页
BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP)is an essential diagnostic and therapeutic procedure for pancreatobiliary disorders.However,few large-scale studies from South Asia have examined long-ter... BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP)is an essential diagnostic and therapeutic procedure for pancreatobiliary disorders.However,few large-scale studies from South Asia have examined long-term ERCP outcomes,particularly using established quality benchmarks.AIM To evaluate ERCP indications,success rates,complications,and quality performance at a high-volume tertiary care center in Pakistan over a 17-year period.METHODS This retrospective study analyzed 13215 ERCP procedures performed between 2006 and 2023.Data included demographics,indications,cannulation rates,complications,and pediatric cases.Findings were assessed against American Society of Gastroenterology/European Society of Gastrointestinal Endoscopy quality indicators.RESULTS Biliary ERCP accounted for 93.1%of procedures;choledocholithiasis was the most common indication(40%).Cannulation success was 93.9%for biliary and 94.2%for pancreatic ERCP.Pediatric ERCP comprised 4%of cases,mostly for stones and chronic pancreatitis.Bleeding(1.7%)and post-ERCP pancreatitis(2.3%)were the most frequent complications.Performance met or exceeded most American Society of Benchmarks.CONCLUSION This study offers insight into nearly two decades of ERCP practice within a public sector hospital.Our experience echoes the quality and efficiency of ERCP not previously available in Pakistan.As healthcare systems in resourcelimited sectors expand,our findings serve as a reference point.Continued training and quality improvement studies can further enhance ERCP effectiveness in the region and beyond. 展开更多
关键词 Endoscopic retrograde cholangiopancreatography PEDIATRIC Adult populations Global comparison BILIARY PANCREATIC Pakistan
暂未订购
Identification of High-Risk Populations: The Cornerstone of Effective and Cost-Efficient Cancer Screening
2
作者 Wei Cao Fei Wang Ni Li 《Biomedical and Environmental Sciences》 2025年第4期401-402,共2页
Cancer screening is a strategy focused on highrisk populations rather than universal populationwide screening, based on a comprehensive evaluation of epidemiological principles and practical feasibility. The effective... Cancer screening is a strategy focused on highrisk populations rather than universal populationwide screening, based on a comprehensive evaluation of epidemiological principles and practical feasibility. The effectiveness of screening depends on factors such as disease prevalence, as well as the sensitivity and specificity of the screening technology employed. 展开更多
关键词 epidemiological principles practical feasibility cancer screening screening technology sensitivity high risk populations disease prevalence practical feasibility epidemiological principles
暂未订购
Evaluation of heterotic effects and inbreeding depression of F_(2) populations of Brassica juncea based on yield and yield-contributing traits
3
作者 Fatema Tuj Johora Niloy Gain +1 位作者 Md.Zahidur Rahman Jamilur Rahman 《Oil Crop Science》 2025年第3期223-234,共12页
Indian mustard is recognized as a resilient and economically important oilseed crop.However,its potential remains untapped due to the limited availability of short-duration,high-yielding varieties capable of out-compe... Indian mustard is recognized as a resilient and economically important oilseed crop.However,its potential remains untapped due to the limited availability of short-duration,high-yielding varieties capable of out-competing other rabi crops.Considering this notion,we have evaluated twenty-one F_(2) and six BC1F1 populations derived from seven diversified parents of Brassica juncea following a Randomized Complete Block Design at Sher-e-Bangla Agricultural University.Based on key agronomic traits,the genetic components,heterosis,inbreeding depression,and gene action were studied to select early maturing and high-yielding populations.The percentage of heterosis was manifested in various cross-combinations,including P4×P6(91.45%for yield per plant)and P5×P6(28.52%for thousand seed weight),emerging as promising candidates for increasing productivity while managing negative inbreeding effects.Conversely,significant inbreeding depression was noted in traits like days to siliquae maturity and yield,particularly in crosses,P1×P2(6.29%)and P3×P5(21.74%),underscoring the need for careful selection in breeding programs to mitigate these effects.Variance analysis indicated that both additive and non-additive genetic interactions play a pivotal role in the inheritance patterns of the traits of interest.Among the six backcrosses,one promising line was(P5×P6)×P5,demonstrating early maturity(107.00 DAS)with improved seed yield(12.47 g).This combination exhibited the potential for enhancing the adaptability and productivity by maintaining the maturity index and accelerating yield.Furthermore,significant phenotypic variation across yield-contributing traits was notable,whereas thousand seed weight and yield per plant showed high broad-sense and narrow-sense of heritability.Besides,positive correlations between seed yield and its attributing traits were noted,suggesting potential avenues for selection breeding.Collectively,the ob-tained findings enhance the understanding of genetic mechanisms underlying heterosis and inbreeding depres-sion in B.juncea,providing insights and effective strategies for developing superior cultivars with optimized agronomic traits. 展开更多
关键词 HETEROSIS Inbreeding depression Genetic components F_(2)populations BACKCROSSING
在线阅读 下载PDF
Allogeneic hematopoietic cell transplantation in vulnerable populations: Advances and perspectives
4
作者 Yi Fan Jia Chen 《Chinese Journal of Cancer Research》 2025年第4期547-550,共4页
Allogeneic hematopoietic cell transplantation(allo-HCT) remains a cornerstone therapy for severe hematologic malignancies, offering a potential cure when conventional therapies are ineffective. However, not all patien... Allogeneic hematopoietic cell transplantation(allo-HCT) remains a cornerstone therapy for severe hematologic malignancies, offering a potential cure when conventional therapies are ineffective. However, not all patients are suitable recipients of allo-HCT, particularly the elderly patients and those with high comorbidity burdens.Furthermore, patients who develop relapse or graft failure after initial transplantation encounter additional challenges when evaluated for a second transplant. 展开更多
关键词 ADVANCES PERSPECTIVES elderly patients conventional therapies severe hematologic malignancies vulnerable populations graft failure allogeneic hematopoietic cell transplantation allo hct
暂未订购
Conservation of Wild Plants with Extremely Small Populations under the Delineation of Ecological Protection Red Lines
5
作者 Shuyan GUO Ying YANG +6 位作者 Qizhen SU Yuan BIAN Lin ZHU Huirui GUAN Zhongyun ZHANG Jin ZHAO Rui JI 《Asian Agricultural Research》 2025年第5期8-19,共12页
The implementation of the ecological protection red line serves as a crucial protective barrier for the conservation of wild plants with extremely small populations by delineating specific geographical areas designate... The implementation of the ecological protection red line serves as a crucial protective barrier for the conservation of wild plants with extremely small populations by delineating specific geographical areas designated for their conservation.The implementation of a comprehensive set of conservation measures aimed at establishing a biodiversity conservation network for wild plants with extremely small populations has laid the foundation for the health and stability of ecosystems,as well as the harmonious coexistence of humans and the natural environment.Research on the conservation of wild plants with extremely small populations serves as a critical foundation for informing and enhancing the effective conservation of such populations.This paper provides a systematic examination of the theoretical and practical conservation status of certain wild plants with extremely small populations and discusses the conservation trends of these populations within the framework of ecological protection red line delineation.In the future,strategies for the conservation of wild plants with extremely small populations should be integrated with an analysis of the causes of endangerment.This approach will provide a robust foundation for applied research focused on the conservation of these vulnerable plant populations. 展开更多
关键词 Wild plants with extremely small populations Conservation research Cause of endangerment Conservation countermeasure
在线阅读 下载PDF
Deep gene exchange break among Konosirus punctatus populations across the northwestern Pacific inferred from AFLP and ISSR markers
6
作者 Na Song Yiping Ying +1 位作者 Yang Zhang Tianxiang Gao 《Acta Oceanologica Sinica》 2025年第1期104-112,共9页
The correct understanding of fish population structure plays a positive role in their fishery management.The dotted gizzard shad,Konosirus punctatus,is widely distributed in the coastal waters of the northwestern Paci... The correct understanding of fish population structure plays a positive role in their fishery management.The dotted gizzard shad,Konosirus punctatus,is widely distributed in the coastal waters of the northwestern Pacific.With the over-exploitation of economically important fishes,its importance is increasingly prominent.To further examine the population genetic structure of K.punctatus across the northwestern Pacific,the amplified fragment length polymorphism(AFLP)and the inter-simple sequence repeats(ISSRs)were employed to perform genetic variation analysis.The results showed that the combination of polyacrylamide gel electrophoresis and silver staining can effectively detect genetic variation for K.punctatus populations.The average proportions of polymorphic loci were 46.26%and 87.13%for AFLP and ISSR markers,respectively,and the genetic diversity parameters showed no obvious differences among populations.Both analysis molecular variance(AMOVA)and pairwise F_(st)suggested that there was significant genetic differentiation between Chinese and Japanese populations.All samples also clustered into two clades based on the unweighted pair-group method analysis(UPGMA)tree by two markers,which indicated significant genetic differentiation among populations.Consistent with the previous studies,there are two highly differentiated groups at the nuclear gene level and they were suggested to be treated as two separate genetic management units.The results of the present study could provide the genetic management strategy for this important economic species. 展开更多
关键词 Konosirus punctatus population genetic differentiation AFLP ISSR
在线阅读 下载PDF
Evolutionary divergence on the Qinghai-Xizang Plateau:How life-history traits shape the diversity of plateau zokor and pika populations
7
作者 Yunyang Wei Tao Zhang +8 位作者 Zifeng Li Qinyang Hua Liduo Yin Menglong Lei Shilei Zhao Shanshan Gu Xin Zhang Hao He Xuemei Lu 《Journal of Genetics and Genomics》 2025年第9期1096-1108,共13页
Understanding how species diverge and adapt is fundamental to unraveling biodiversity.While environmental impacts on species evolution are well-documented,the roles of intrinsic life-history traits remain underexplore... Understanding how species diverge and adapt is fundamental to unraveling biodiversity.While environmental impacts on species evolution are well-documented,the roles of intrinsic life-history traits remain underexplored.The Qinghai-Xizang Plateau,with its harsh conditions and unique biodiversity,offers a natural laboratory for such investigations.Here,we examine two sympatric small mammals—the solitary,low-dispersal plateau zokor(Eospalax baileyi)and the social,high-dispersal plateau pika(Ochotona curzoniae)—to elucidate how life-history traits shape population structures and adaptive strategies.Through whole-genome sequencing and cardiac-blood phenotype analyses,we reveal striking differences in their evolutionary trajectories.Despite enduring similar environmental pressures,plateau zokor populations exhibit pronounced genetic subdivisions,high inbreeding,and distinct local adaptations.In contrast,plateau pika populations display genetic panmixia,widespread diversity,and adaptive uniformity.Demographic inference highlights that plateau zokors experienced severe population bottlenecks and restricted gene flow during glacial periods,underscoring the impact of dispersal capacity on evolutionary outcomes.Our findings demonstrate that intrinsic biological traits,particularly dispersal ability,fundamentally influence genetic architecture,population connectivity,and local adaptation.This study not only provides empirical evidence of how life-history traits shape evolutionary dynamics but also offers a framework for integrating intrinsic and extrinsic factors in understanding biodiversity formation. 展开更多
关键词 Life-history traits Population structure High-altitude adaptation Genetic diversity Plateau zokor Plateau pika
原文传递
Enhanced risk assessment framework integrating distribution dynamics,genetically inferred populations,and morphological traits of Diploderma lizards
8
作者 Qi Xiao Xiu-Dong Shi +5 位作者 Lin Shi Zhong-Yi Yao You-Hua Chen Wei-Zhao Yang Zi-Yan Liao Yin Qi 《Zoological Research》 2025年第1期15-26,共12页
Assessing the threat status of species in response to global change is critical for biodiversity monitoring and conservation efforts.However,current frameworks,even the IUCN Red List,often neglect critical factors suc... Assessing the threat status of species in response to global change is critical for biodiversity monitoring and conservation efforts.However,current frameworks,even the IUCN Red List,often neglect critical factors such as genetic diversity and the impacts of climate and land-use changes,hindering effective conservation planning.To address these limitations,we developed an enhanced extinction risk assessment framework using Diploderma lizards as a model.This framework incorporates long-term field surveys,environmental data,and land-use information to predict distributional changes for 10 recently described Diploderma species on the Qinghai-Xizang Plateau,which hold ecological significance but remain underassessed in conservation assessment.By integrating the distribution data and genetically inferred effective population sizes(Ne),we conducted scenario analyses and used a rank-sum approach to calculate Risk ranking scores(RRS)for each species.This approach revealed significant discrepancies with the IUCN Red List assessments.Notably,D.yangi and D.qilin were identified as facing the highest extinction risk.Furthermore,D.vela,D.batangense,D.flaviceps,D.dymondi,D.yulongense,and D.laeviventre,currently classified as“Least Concern”,were found to warrant reclassification as“Vulnerable”due to considerable threat from projected range contractions.Exploring the relationship between morphology and RRS revealed that traits such as snout-vent length and relative tail length could serve as potential predictors of extinction risk,offering preliminary metrics for assessing species vulnerability when comprehensive data are unavailable.This study enhances the precision of extinction risk assessment frameworks and demonstrates their capacity to refine and update risk assessments,especially for lesser-known taxa. 展开更多
关键词 LIZARD Extinction Risk Assessment IUCN Red List Conservation Status Effective Population Size Morphological Traits
在线阅读 下载PDF
Elevated extinction risk of low-elevation populations of two songbirds on the Taiwan island
9
作者 Xuntao Ma Yadan Liu +2 位作者 Zhang Zhang Mingwang Zhang Feng Dong 《Avian Research》 2025年第3期467-472,共6页
Prevailing concerns on mountainous biodiversity are concentrated on the impacts of climate change at higher elevations. However, the lower elevations are facing additional human disturbance and are expected to suffer ... Prevailing concerns on mountainous biodiversity are concentrated on the impacts of climate change at higher elevations. However, the lower elevations are facing additional human disturbance and are expected to suffer from higher extinction risk but have attracted less conservation attention. Here, we employed population genomics to compare extinction risk two common songbirds—the Vinous-throated Parrotbill (Sinosuthora webbiana) and the Rufous-capped Babbler (Cyanoderma ruficeps)—at lower and higher elevations on the Taiwan island. As the result, we observed decreased genetic diversity and increased genetic load and thus elevated extinction risk in the low-elevation populations of both birds in the eastern slope of the Central Mountains on the Taiwan island. In contrast, genetic-load patterns of both birds in the western slope might be confused by substantial gene flow across lower and higher elevations. These results, on the one hand, call for conservation efforts to lower elevations in mountains and, on the other hand, highlight the importance of population connection in maintaining population viability under impending global change. 展开更多
关键词 Extinction risk Genetic load Human disturbance Mountainous biodiversityi Population genomics
在线阅读 下载PDF
KCNQ1 rs2237895 gene polymorphism increases susceptibility to type 2 diabetes mellitus in Asian populations 被引量:1
10
作者 Dong-Xu Li Li-Ping Yin +4 位作者 Yu-Qi Song Nan-Nan Shao Huan Zhu Chen-Sen He Jiang-Jie Sun 《World Journal of Diabetes》 SCIE 2024年第3期552-564,共13页
BACKGROUND The association of single nucleotide polymorphism of KCNQ1 gene rs2237895 with type 2 diabetes mellitus(T2DM)is currently controversial.It is unknown whether this association can be gene realized across dif... BACKGROUND The association of single nucleotide polymorphism of KCNQ1 gene rs2237895 with type 2 diabetes mellitus(T2DM)is currently controversial.It is unknown whether this association can be gene realized across different populations.AIM To determine the association of KCNQ1 rs2237895 with T2DM and provide reliable evidence for genetic susceptibility to T2DM.METHODS We searched PubMed,Embase,Web of Science,Cochrane Library,Medline,Baidu Academic,China National Knowledge Infrastructure,China Biomedical Literature Database,and Wanfang to investigate the association between KCNQ1 gene rs2237895 and the risk of T2DM up to January 12,2022.Review Manager 5.4 was used to analyze the association of the KCNQ1 gene rs2237895 polymorphism with T2DM and to evaluate the publication bias of the selected literature.RESULTS Twelve case–control studies(including 11273 cases and 11654 controls)met our inclusion criteria.In the full population,allelic model[odds ratio(OR):1.19;95%confidence interval(95%CI):1.09–1.29;P<0.0001],recessive model(OR:1.20;95%CI:1.11–1.29;P<0.0001),dominant model(OR:1.27.95%CI:1.14–1.42;P<0.0001),and codominant model(OR:1.36;95%CI:1.15–1.60;P=0.0003)(OR:1.22;95%CI:1.10–1.36;P=0.0002)indicated that the KCNQ1 gene rs2237895 polymorphism was significantly correlated with susceptibility to T2DM.In stratified analysis,this association was confirmed in Asian populations:allelic model(OR:1.25;95%CI:1.13–1.37;P<0.0001),recessive model(OR:1.29;95%CI:1.11–1.49;P=0.0007),dominant model(OR:1.35;95%CI:1.20–1.52;P<0.0001),codominant model(OR:1.49;95%CI:1.22–1.81;P<0.0001)(OR:1.26;95%CI:1.16–1.36;P<0.0001).In non-Asian populations,this association was not significant:Allelic model(OR:1.06,95%CI:0.98–1.14;P=0.12),recessive model(OR:1.04;95%CI:0.75–1.42;P=0.83),dominant model(OR:1.06;95%CI:0.98–1.15;P=0.15),codominant model(OR:1.08;95%CI:0.82–1.42;P=0.60.OR:1.15;95%CI:0.95–1.39;P=0.14).CONCLUSION KCNQ1 gene rs2237895 was significantly associated with susceptibility to T2DM in an Asian population.Carriers of the C allele had a higher risk of T2DM.This association was not significant in non-Asian populations. 展开更多
关键词 Type 2 diabetes mellitus KCNQ1 rs2237895 Single nucleotide polymorphism Asian populations
暂未订购
Evolutionary game dynamics of combining two different aspiration-driven update rules in structured populations
11
作者 杨智昊 杨彦龙 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期182-191,共10页
In evolutionary games,most studies on finite populations have focused on a single updating mechanism.However,given the differences in individual cognition,individuals may change their strategies according to different... In evolutionary games,most studies on finite populations have focused on a single updating mechanism.However,given the differences in individual cognition,individuals may change their strategies according to different updating mechanisms.For this reason,we consider two different aspiration-driven updating mechanisms in structured populations:satisfied-stay unsatisfied shift(SSUS)and satisfied-cooperate unsatisfied defect(SCUD).To simulate the game player’s learning process,this paper improves the particle swarm optimization algorithm,which will be used to simulate the game player’s strategy selection,i.e.,population particle swarm optimization(PPSO)algorithms.We find that in the prisoner’s dilemma,the conditions that SSUS facilitates the evolution of cooperation do not enable cooperation to emerge.In contrast,SCUD conditions that promote the evolution of cooperation enable cooperation to emerge.In addition,the invasion of SCUD individuals helps promote cooperation among SSUS individuals.Simulated by the PPSO algorithm,the theoretical approximation results are found to be consistent with the trend of change in the simulation results. 展开更多
关键词 evolutionary game dynamics aspiration-driven update structured populations
原文传递
Comparative Study of Genetic Structure and Genetic Diversity betweenWild and Cultivated Populations of Taxus cuspidata,Northeast China 被引量:2
12
作者 Dandan Wang Xiaohong Li Yanwen Zhang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期355-369,共15页
Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is... Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is,33 wild yews and 28 cultivated yews were used to analyze the differences and correlations of the kinship,genetic diversity,and genetic structure between them by specific length amplified fragment sequencing(SLAF-seq).Finally,470725 polymorphic SLAF tags and 58622 valid SNP markers were obtained.Phylogenetic analysis showed that 61 samples were classified into 2 clusters:wild populations and cultivated populations,and some wild yews were categorized into the cultivated populations;the genetic diversity analysis showed that the Nei diversity index of wild populations(0.4068)was smaller than that of cultivated populations(0.4414),and the polymorphic information content(PIC)of wild populations(0.2861)was smaller than that of cultivated populations(0.3309).The genetic differentiation analysis showed that the total populations of gene diversity(H_(t))of cultivated and wild populations were respectively 0.8159 and 0.5685,the coefficient of gene differentiation(G_(st))of cultivated and wild populations was respectively 0.3021 and 0.1068,and the gene flow(N_(m))(2.4967)of wild populations was larger than cultivated populations(0.8199).The molecular variance(AMOVA)revealed that inter-population variation accounted for 29.57%of the total genetic variation,while intra-population variation accounted for 70.42% of the total genetic variation(p<0.001),this suggested that the genetic variation in the T.cuspidata is mainly attributed to within-population factors.In conclusion,the genetic distance between geographical ecological groups of wild populations was generally smaller than that of cultivated populations,and the degree of genetic diversity and genetic differentiation was smaller than that of cultivated populations.As evident,the utilization of SLAF-seq technology enables efficient and accurate development of SNP markers suitable for genetic analysis of T.cuspidata species.These developed SNP markers can provide a molecular foundation for T.cuspidata breeding,construction of genetic maps,variety identification,and association analysis of agronomic traits. 展开更多
关键词 T.cuspidata SLAF-seq SNP wild population cultivated population genetic structure
在线阅读 下载PDF
Changes in the adult sex ratio of six duck species breeding populations over two decades
13
作者 Monika Homolkova Petr Musil +4 位作者 Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova Sarka Neuzilova Jan Zouhar 《Avian Research》 SCIE CSCD 2024年第2期202-210,共9页
Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of research... Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered species.Species with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction risk.In this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard Netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in South Bohemia,Czechia,between 2004 and 2022.This evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the NAO index(North Atlantic Oscillation index)on them,indicating climate conditions in winter.We determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and males.In the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early 2020s.However,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population. 展开更多
关键词 Adult sex ratio Breeding population Population dynamics Red-listed species WATERFOWL Winter weather conditions
在线阅读 下载PDF
A homing rescue gene drive with multiplexed gRNAs reaches high frequency in cage populations but generates functional resistance
14
作者 Shibo Hou Jingheng Chen +3 位作者 Ruobing Feng Xuejiao Xu Nan Liang Jackson Champer 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2024年第8期836-843,共8页
CRISPR homing gene drives have considerable potential for managing populations of medically and agriculturally significant insects.They operate by Cas9 cleavage followed by homology-directed repair,copying the drive a... CRISPR homing gene drives have considerable potential for managing populations of medically and agriculturally significant insects.They operate by Cas9 cleavage followed by homology-directed repair,copying the drive allele to the wild-type chromosome and thus increasing in frequency and spreading throughout a population.However,resistance alleles formed by end-joining repair pose a significant obstacle.To address this,we create a homing drive targeting the essential hairy gene in Drosophila melanogaster.Nonfunctional resistance alleles are recessive lethal,while drive carriers have a recoded“rescue”version of hairy.The drive inheritance rate is moderate,and multigenerational cage studies show drive spread to 96%–97%of the population.However,the drive does not reach 100%due to the formation of functional resistance alleles despite using four gRNAs.These alleles have a large deletion but likely utilize an alternate start codon.Thus,revised designs targeting more essential regions of a gene may be necessary to avoid such functional resistance.Replacement of the rescue element’s native 3'UTR with a homolog from another species increases drive inheritance by 13%–24%.This was possibly because of reduced homology between the rescue element and surrounding genomic DNA,which could also be an important design consideration for rescue gene drives. 展开更多
关键词 Genedrive Homing drive Rescueelement Population modification Multiplexed gRNAs Resistance alleles Cage study
原文传递
Photosynthetic response to a winter heatwave in leading and trailing edge populations of the intertidal red alga Corallina offi-cinalis(Rhodophyta)
15
作者 Regina Kolzenburg Federica Ragazzola +3 位作者 Laura Tamburello Katy R.Nicastro Christopher D.McQuaid Gerardo I.Zardi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第7期70-77,共8页
Marine heatwaves(MHWs)caused by anthropogenic climate change are becoming a key driver of change at the ecosystem level.Thermal conditions experienced by marine organisms across their distribution,particularly towards... Marine heatwaves(MHWs)caused by anthropogenic climate change are becoming a key driver of change at the ecosystem level.Thermal conditions experienced by marine organisms across their distribution,particularly towards the equator,are likely to approach their physiological limits,resulting in extensive mortality and subsequent changes at the population level.Populations at the margins of their species’distribution are thought to be more sensitive to climate-induced environmental pressures than central populations,but our understanding of variability in fitness-related physiological traits in trailing versus leading-edge populations is limited.In a laboratory simulation study,we tested whether two leading(Iceland)and two trailing(Spain)peripheral populations of the intertidal macroalga Corallina officinalis display different levels of maximum potential quantum efficiency(Fv/Fm)resilience to current and future winter MHWs scenarios.Our study revealed that ongoing and future local winter MHWs will not negatively affect leading-edge populations of C.officinalis,which exhibited stable photosynthetic efficiency throughout the study.Trailing edge populations showed a positive though non-significant trend in photosynthetic efficiency throughout winter MHWs exposure.Poleward and equatorward populations did not produce significantly different results,with winter MHWs having no negative affect on Fv/Fm of either population.Additionally,we found no long-term regional or population-level influence of a winter MHWs on this species’photosynthetic efficiency.Thus,we found no statistically significant difference in thermal stress responses between leading and trailing populations.Nonetheless,C.officinalis showed a trend towards higher stress responses in southern than northern populations.Because responses rest on a variety of local population traits,they are difficult to predict based solely on thermal pressures. 展开更多
关键词 marginal population coralline algae climate change ECOPHYSIOLOGY PHOTOPHYSIOLOGY MACROALGAE FV/FM
在线阅读 下载PDF
Multi-environment BSA-seq using large F3 populations is able to achieve reliable QTL mapping with high power and resolution: An experimental demonstration in rice
16
作者 Yan Zheng Ei Ei Khine +9 位作者 Khin Mar Thi Ei Ei Nyein Likun Huang Lihui Lin Xiaofang Xie Min Htay Wai Lin Khin Than Oo Myat Myat Moe San San Aye Weiren Wu 《The Crop Journal》 SCIE CSCD 2024年第2期549-557,共9页
Bulked-segregant analysis by deep sequencing(BSA-seq) is a widely used method for mapping QTL(quantitative trait loci) due to its simplicity, speed, cost-effectiveness, and efficiency. However, the ability of BSA-seq ... Bulked-segregant analysis by deep sequencing(BSA-seq) is a widely used method for mapping QTL(quantitative trait loci) due to its simplicity, speed, cost-effectiveness, and efficiency. However, the ability of BSA-seq to detect QTL is often limited by inappropriate experimental designs, as evidenced by numerous practical studies. Most BSA-seq studies have utilized small to medium-sized populations, with F2populations being the most common choice. Nevertheless, theoretical studies have shown that using a large population with an appropriate pool size can significantly enhance the power and resolution of QTL detection in BSA-seq, with F_(3)populations offering notable advantages over F2populations. To provide an experimental demonstration, we tested the power of BSA-seq to identify QTL controlling days from sowing to heading(DTH) in a 7200-plant rice F_(3)population in two environments, with a pool size of approximately 500. Each experiment identified 34 QTL, an order of magnitude greater than reported in most BSA-seq experiments, of which 23 were detected in both experiments, with 17 of these located near41 previously reported QTL and eight cloned genes known to control DTH in rice. These results indicate that QTL mapping by BSA-seq in large F_(3)populations and multi-environment experiments can achieve high power, resolution, and reliability. 展开更多
关键词 BSA-seq QTL mapping Large F3 population Multi-environment experiment Cross-validation
在线阅读 下载PDF
Dependence of Rydberg-atom-based sensor performance on different Rydberg atom populations in one atomic-vapor cell
17
作者 武博 姚佳伟 +2 位作者 吴逢川 安强 付云起 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期365-370,共6页
The atomic-vapor cell is a vital component for Rydberg atomic microwave sensors,and impacts on overall capability of Rydberg sensors.However,the conventional analysis approach on effect of vapor-cell length contains t... The atomic-vapor cell is a vital component for Rydberg atomic microwave sensors,and impacts on overall capability of Rydberg sensors.However,the conventional analysis approach on effect of vapor-cell length contains two implicit assumptions,that is,the same atomic population density and buffer gas pressure,which make it unable to accurately capture actual response about effect of Rydberg-atom-based sensor performance on different Rydberg atom populations.Here,utilizing a stepped cesium atomic-vapor cell with five different dimensions at the same atomic population density and buffer gas pressure,the height and full width at half maximum of electromagnetically induced transparency(EIT)signal,and the sensitivity of the atomic superheterodyne sensor are comprehensively investigated under conditions of the same Rabi frequencies(saturated laser power).It is identified that EIT signal height is proportional to the cell length,full width at half maximum and sensitivity grow with the increment of cell length to a certain extent.Employing the coherent integration signal theory and atomic linear expansion coefficient method,theoretical analysis of the EIT height and sensitivity are further investigated.The results could shed new light on understanding and design of ultrahigh-sensitivity Rydberg atomic microwave sensors and find promising applications in quantum measurement,communication,and imaging. 展开更多
关键词 Rydberg atom population Rydberg-atom-based receiver stepped atomic-vapor cell
原文传递
Analysis of Genetic Structure of Natural Populations of Castanopsis fargesii by RAPDs 被引量:12
18
作者 朱其慧 潘惠新 +3 位作者 诸葛强 尹佟明 邹惠渝 黄敏仁 《Acta Botanica Sinica》 CSCD 2002年第11期1321-1326,共6页
Genetic diversity and population genetic structure in 188 individuals from five natural populations of Castampsis fargesii Franch. were studied by RAPD markers. Three hundred and eighty-five loci were identified with ... Genetic diversity and population genetic structure in 188 individuals from five natural populations of Castampsis fargesii Franch. were studied by RAPD markers. Three hundred and eighty-five loci were identified with 41 oligonucleotide primers, out of which 157 loci were polymorphic and accounted for 40.78% of total genetic diversity at species level. Shannon's indices of diversity (I) and Nei's gene diversity ( h) were 0.459 7 and 0.296 at the species level, respectively. The result showed that genetic variation of C. fargesii populations mainly existed within populations. Genetic differentiation (Hsp-hpop)/Hsp estimated with Shannon's index of diversity and coefficient of gene differentiation (Gst) were 0.047 6 and 0.042 9 respectively, which were confirmed by the analysis of molecular variance (AMOVA). Therefore, it is apparent that within-population variation accounted for 94.97% and among-populations variation accounted for only 5.03% of the total genetic diversity. AMOVA also indicated that there was significant differentiation among populations as well as among individuals within a population. 展开更多
关键词 Castanopsis fargesii natural populations RAPD genetic structure
在线阅读 下载PDF
Multi Location Field Evaluation of BC1F2 Sorghum Populations for Striga Resistance in Niger
19
作者 Ousseini Ardaly Abdou Aissata Mamadou Ibrahim +2 位作者 Yaw Eleblu John Saviour Ofori Kwadwo Ousmane Zakari Moussa 《American Journal of Plant Sciences》 CAS 2024年第10期1010-1021,共12页
In Niger, a landlocked country, sorghum is the second staple food cultivated over the country by smallholder farmer. The crop is important for human and animal consumption. Despite its importance, the crop is affected... In Niger, a landlocked country, sorghum is the second staple food cultivated over the country by smallholder farmer. The crop is important for human and animal consumption. Despite its importance, the crop is affected by biotic and abiotic constraints. Among those constraints, striga has a high impact on yield. In fact, to survive, farmers are growing their local preferred sorghum varieties wish is highly sensible to the weed. Striga management is a challenge that requires a permanent solution. In addition, the development of high-yielding Striga resistant genotypes will be appreciated by farmers. The development of striga resistance will be based on the breeding population performances under farmer’s diverse environmental conditions adaptation. The main objective of this study is to evaluate two breeding populations for striga resistance in two different environments at Boulke and Dibissou in Tahoua region, to identify the early and high-yielding striga tolerant genotypes under natural infestation. 展开更多
关键词 Striga Resistance SORGHUM Breeding Population Multi Environment
在线阅读 下载PDF
上一页 1 2 179 下一页 到第
使用帮助 返回顶部