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Comparative Study of Genetic Structure and Genetic Diversity betweenWild and Cultivated Populations of Taxus cuspidata,Northeast China
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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
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Evolutionary game dynamics of combining two different aspiration-driven update rules in structured populations
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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
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Dependence of Rydberg-atom-based sensor performance on different Rydberg atom populations in one atomic-vapor cell
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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
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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
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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
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KCNQ1 rs2237895 gene polymorphism increases susceptibility to type 2 diabetes mellitus in Asian populations
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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
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Study on Resource Status and Protection Countermeasures of Wild Plant Species with Extremely Small Populations(PSESP)in Xinjiang
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作者 Li CHEN Ting NIU Xin HAN 《Meteorological and Environmental Research》 CAS 2022年第2期83-97,I0002-I0010,共24页
In recent years,the protection of PSESP has gradually become a hot issue in biodiversity research.Through the investigation and analysis of PSESP in Xinjiang,it is shown that:①there are 75 species of PSESP in Xinjian... In recent years,the protection of PSESP has gradually become a hot issue in biodiversity research.Through the investigation and analysis of PSESP in Xinjiang,it is shown that:①there are 75 species of PSESP in Xinjiang,including 22 species of trees,18 species of shrubs and 35 species of herbs.The habitats are mainly in extremely cold,extremely dry or extremely narrow conditions such as snow line,desert,mountain,wetland and so on.②53 species(70.67%)are listed as national or autonomous region protected plants,and 22 species of PSESP are not listed in the protection;there are 70 species of PSESP listed in the red list,accounting for 93.33%.③The PSESP in Xinjiang are mainly distributed in the Altai Mountains,western Tianshan Mountains,Pamir Plateau and Karakoram Mountains;they are distributed in all kinds of nature reserves,forest parks,wetland parks and other natural ecological protection areas in Xinjiang.Ammopiptanthus nanus(M.Pop.)Cheng F.,Cistanche tubulosa(Schenk)Wight,Calligonum roborovskii A.Los.and Prunus cerasifera Ehrhart have not been found in the literature,indicating that they are distributed in protected areas.In order to provide a theoretical basis for the conservation of biodiversity in Xinjiang,this paper puts forward some suggestions on the protection of PSESP. 展开更多
关键词 Wild plant species with extremely small populations(psesp) Resource status Protection countermeasures XINJIANG
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Research Progress on Manglietia ventii,A Wild Plant Species with Extremely Small Populations
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作者 Bin WANG Xinglin AN +3 位作者 Zherong WU Hongmei ZHAO Xiangxin YU Xingmei AI 《Asian Agricultural Research》 2023年第3期40-46,共7页
Manglietia ventii is a wild plant species with extremely small populations endemic to Yunnan,mainly distributed in southeast Yunnan.Due to the continuous deterioration of natural habitats,excessive felling and utiliza... Manglietia ventii is a wild plant species with extremely small populations endemic to Yunnan,mainly distributed in southeast Yunnan.Due to the continuous deterioration of natural habitats,excessive felling and utilization of human beings,and the decline of breeding ability,the number of individuals in the population has decreased significantly.Through field investigation and literature review,the research status of M.ventii in systematics,conservation ecology,reproductive biology,genetic diversity,endangered mechanism and resource protection at home and abroad are systematically reviewed.And the future research direction is prospected.It is necessary to strengthen the research on the basic characteristics of M.ventii,explore the transmission route of M.ventii and deepen the development and utilization of resources,in order to provide a theoretical support for the protection and sustainable utilization of germplasm resources of M.ventii,and provide a reference for the protection of other wild plant species with extremely small populations. 展开更多
关键词 Manglietia ventii Plant species with extremely small populations(psesp) Research progress
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State of Local Populations of Aegilops triuncalis L. in Uzbekistan
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作者 Mamatkasimov T. Odilbek Abduraimov S. Ozodbek +2 位作者 Maxmudov V. Azizbek Mavlanov J. Bekzod Allamurotov L. Akmal 《American Journal of Plant Sciences》 2023年第11期1305-1315,共11页
The genus Aegilops L. is considered one of the important representatives of the wild relative of cultivated plants. The article presents the place of Aegilops triuncialis L. in plant communities and the status of popu... The genus Aegilops L. is considered one of the important representatives of the wild relative of cultivated plants. The article presents the place of Aegilops triuncialis L. in plant communities and the status of populations in the flora of Uzbekistan. The research was carried out in various botanical and geographical regions of Uzbekistan during 2021-2023 years. During the research, the existing literature and geobotanical records, samples stored in the Institute of Botany (TASH) fund, and data on the GBIF international website were analyzed. Based on literary sources, more than 100 local points were recorded. The vitality structure of 11 cenopopulations was studied during field research. Various abiotic and biotic factors influencing the state of populations were analyzed. The main cenopopulations of the species were observed to spread in various grassy shrubland communities. 展开更多
关键词 Aegilops triuncalis L. Uzbekistan POPULATION DISTRIBUTION FLORA HERBARIUM TASH
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Comparative study of type 2 diabetes mellitus-associated gut microbiota between the Dai and Han populations
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作者 Ling-Tong Tang Lei Feng +6 位作者 Hui-Ying Cao Rui Shi Bei-Bei Luo Yan-Bi Zhang Yan-Mei Liu Jian Zhang Shuang-Yue Li 《World Journal of Diabetes》 SCIE 2023年第12期1766-1783,共18页
BACKGROUND The global prevalence of type 2 diabetes mellitus(T2DM)is increasing.T2DM is associated with alterations of the gut microbiota,which can be affected by age,illness,and genetics.Previous studies revealed tha... BACKGROUND The global prevalence of type 2 diabetes mellitus(T2DM)is increasing.T2DM is associated with alterations of the gut microbiota,which can be affected by age,illness,and genetics.Previous studies revealed that there are discriminating microbiota compositions between the Dai and the Han populations.However,the specific gut microbiota differences between the two populations have not been elucidated.AIM To compare the gut microbiota differences in subjects with and without T2DM in the Dai and Han populations.METHODS A total of 35 subjects of the Han population(including 15 healthy children,8 adult healthy controls,and 12 adult T2DM patients)and 32 subjects of the Dai population(including 10 healthy children,10 adult healthy controls,and 12 adult T2DM patients)were enrolled in this study.Fasting venous blood samples were collected from all the subjects for biochemical analysis.Fecal samples were collected from all the subjects for DNA extraction and 16S rRNA sequencing,which was followed by analyses of the gut microbiota composition.RESULTS No significant difference in alpha diversity was observed between healthy children and adults.The diversity of gut microbiota was decreased in T2DM patients compared to the healthy adults in both the Dai and Han populations. There was a significant difference in gut microbiota between healthy children and healthy adults in the Hanpopulation with an increased abundance of Bacteroidetes and decreased Firmicutes in children. However, thisdifference was less in the Dai population. Significant increases in Bacteroidetes in the Han population and Proteobacteriain the Dai population and decreases in Firmicutes in both the Han and Dai population were observed inT2DM patients compared to healthy adults. Linear discriminant analysis Effect Size analysis also showed that thegut microbiota was different between the Han and Dai populations in heathy children, adults, and T2DM patients.Four bacteria were consistently increased and two consistently decreased in the Han population compared to theDai population.CONCLUSION Differences in gut microbiota were found between the Han and Dai populations. A significant increase inBacteroidetes was related to the occurrence of T2DM in the Han population, while a significant increase in Proteobacteriawas related to the occurrence of T2DM in the Dai population. 展开更多
关键词 Gut microbiota Type 2 diabetes mellitus Dai population Han population GENETICS ETHNIC
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Ozone pollution threatens bird populations to collapse:an imminent ecological threat?
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作者 Evgenios Agathokleous Pierre Sicard +1 位作者 Zhaozhong Feng Elena Paoletti 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1653-1656,共4页
While bird populations are declining,the factors associated with this decline are unclear.Based on laboratory experiments,air pollution has long been recognized as a factor causing oxidative stress and adversely aff e... While bird populations are declining,the factors associated with this decline are unclear.Based on laboratory experiments,air pollution has long been recognized as a factor causing oxidative stress and adversely aff ecting bird health.Recently,studies employing an epidemiological approach have reported signifi cant declines in avian populations in Central Europe and the United States due to air pollution,and ozone in particular.We advocate that urgent actions are needed to mitigate these eff ects,which threaten biodiversity and environmental health,and propose a series of measures which can enlighten the path toward mitigating air pollution eff ects on avian populations. 展开更多
关键词 Air pollution BIOSECURITY Bird population BIODIVERSITY ORNITHOLOGY Ozone risk
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Control of epileptic activities in a cortex network of multiple coupled neural populations under electromagnetic induction
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作者 Zhongkui SUN Yuanyuan LIU +1 位作者 Xiaoli YANG Wei XU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第3期499-514,共16页
Epilepsy is believed to be associated with the abnormal synchronous neuronal activity in the brain,which results from large groups or circuits of neurons.In this paper,we choose to focus on the temporal lobe epilepsy,... Epilepsy is believed to be associated with the abnormal synchronous neuronal activity in the brain,which results from large groups or circuits of neurons.In this paper,we choose to focus on the temporal lobe epilepsy,and establish a cortex network of multiple coupled neural populations to explore the epileptic activities under electromagnetic induction.We demonstrate that the epileptic activities can be controlled and modulated by electromagnetic induction and coupling among regions.In certain regions,these two types of control are observed to show exactly reverse effects.The results show that the strong electromagnetic induction is conducive to eliminating the epileptic seizures.The coupling among regions has a conduction effect that the previous normal background activity of the region gives way to the epileptic discharge,owing to coupling with spike wave discharge regions.Overall,these results highlight the role of electromagnetic induction and coupling among the regions in controlling and modulating epileptic activities,and might provide novel insights into the treatments of epilepsy. 展开更多
关键词 EPILEPSY electromagnetic induction multiple coupled neural population dynamical transition
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Genome-wide recombination variation in biparental segregating and reciprocal backcross populations provides information for introgression breeding in Brassica napus
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作者 Meng Wang Graham J.King +6 位作者 Lei Shi Ruiyuan Li Yi Zhang Xiaohua Wang Jinling Meng Jinxing Tu Jun Zou 《The Crop Journal》 SCIE CSCD 2023年第1期208-219,共12页
Variation in patterns of recombination in plant genomes provides information about species evolution,genetic diversity and crop improvement. We investigated meiotic crossovers generated in biparental segregating and r... Variation in patterns of recombination in plant genomes provides information about species evolution,genetic diversity and crop improvement. We investigated meiotic crossovers generated in biparental segregating and reciprocal backcross populations of the allopolyploid genome of rapeseed(Brassica napus)(AACC, 2n = 38). A structured set of 1445 intercrossed lines was derived from two homozygous de novo genome-assembled parents that represented the major genetic clusters of semi-winter Chinese and winter European rapeseeds, and was used to increase QTL resolution and achieve genomic reciprocal introgression. A high-density genetic map constructed with 6161 genetic bins and anchored centromere regions was used to establish the pattern of recombination variation in each chromosome. Around 93%of the genome contained crossovers at a mean rate of 3.8 c M Mb^(-1), with the remaining 7% attributed to centromeres or low marker density. Recombination hotspots predominated in the A genome, including two-thirds of those associated with breeding introgression from B. rapa. Genetic background might affect recombination variation. Introgression of genetic diversity from European winter to Chinese semi-winter rapeseed showed an increase in crossover rate under the semi-winter environment. Evidence for an elevated recombination rate having historically contributed to selective trait improvement includes accumulation of favorable alleles for seed oil content on hotspots of chromosome A10. Conversely, strong artificial selection may affect recombination rate variation, as appears to be the case with a coldspot resulting from strong selection for glucosinolate alleles on A09. But the cold region would be promptly reactivated by crossing design indicated by the pedigree analysis. Knowledge of recombination hotspots and coldspots associated with QTL for 22 traits can guide selection strategies for introgression breeding between the two gene pools. These results and rich genomic resources broaden our understanding of recombination behavior in allopolyploids and may advance rapeseed genetic improvement. 展开更多
关键词 ALLOPOLYPLOID Meiotic crossovers Brassica napus Historical introgression Reciprocal backcross population
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Measuring stellar populations,dust attenuation and ionized gas at kpc scales in 10010 nearby galaxies using the integral field spectroscopy from MaNGA
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作者 李牛 李成 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期1-7,共7页
As one of the three major experiments of the fourth-generation Sloan Digital Sky Survey(SDSS-IV),the Mapping Nearby Galaxies at Apatch Point Observatory(MaNGA)survey has obtained high-quality integral field spectrosco... As one of the three major experiments of the fourth-generation Sloan Digital Sky Survey(SDSS-IV),the Mapping Nearby Galaxies at Apatch Point Observatory(MaNGA)survey has obtained high-quality integral field spectroscopy(IFS)with a resolution of 1–2 kpc for104galaxies in the local universe during its six-year operation from July 2014 through August 2020.It is crucial to reliably measure the physical properties of the different components in each spectrum before one can use the data for any scientific study.In the past years we have made lots of efforts to develop a novel technique of full spectral fitting,which estimates a model-independent dust attenuation curve from each spectrum,thus allowing us to break the degeneracy between dust attenuation and stellar population properties when fitting the spectrum with stellar population synthesis models.We have applied our technique to the final data release of Ma NGA,and obtained measurements of stellar population properties and emission line parameters,as well as the kinematics and dust attenuation of both stellar and ionized gas components.In this paper we describe our technique and the content and format of our data products.The whole dataset is publicly available in Science Data Bank with the link https://doi.org/10.57760/sciencedb.j00113.00088. 展开更多
关键词 integral field spectroscopy stellar populations dust attenuation ionized gas
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An easy,convenient statistical method to analyze bark beetle populations
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作者 Andrzej Borkowski 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期2027-2040,共14页
A non-invasive method to estimate the number of Trypodendron lineatum holes on dead standing pines(Pinus sylvestris L.)was developed using linear and nonlinear estimations.A clas sical linear regres sion model was fir... A non-invasive method to estimate the number of Trypodendron lineatum holes on dead standing pines(Pinus sylvestris L.)was developed using linear and nonlinear estimations.A clas sical linear regres sion model was first used to analyze the relationship between the number of holes caused by T.lineatum on selected stem units and the total number of holes on an entire dead stem of P.sylvestris.Then,to obtain a better fit of the regression function to the data for the stem unit selected in the first step,piecewise linear regression(PLR)was used.Last,in an area used to evaluate wood decomposition(method validation),the total and mean numbers of T.lineatum holes were estimated for single dead trees and for a sample(n=8 dead trees).Data were collected in 2009(data set D1),in 2010-2014(data set D2)and in 2020(data set D3)in forests containing P.sylvestris located within Suchedniow-Oblegorek Landscape Park,Poland.A model was constructed with three linear equations.An evaluation of model accuracy showed that it was highly effective regardless of the density of T.lineatum holes and sample size.The method enables the evaluation of the biological role of this species in the decomposition of dead standing wood of P.sylvestris in strictly protected areas. 展开更多
关键词 Trypodendron lineatum Pinus sylvestris POPULATION Wood decomposition Forest management Piecewise linear regression
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Leadership,communication,and science:three pillars essential to public health emergency response and closing the gap in the HIV response among key populations
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作者 Tafadzwa Dzinamarira Enos Moyo +2 位作者 Perseverance Moyo Munashe Chimene Grant Murewanhema 《Global Health Journal》 2023年第4期182-185,共4页
Globally,there have been multiple public health emergencies in recent decades.High rates of morbidity,occasionally mortality,and economic instability are usually associated with pandemics.One of the epidemics that has... Globally,there have been multiple public health emergencies in recent decades.High rates of morbidity,occasionally mortality,and economic instability are usually associated with pandemics.One of the epidemics that has significantly increased morbidity and mortality worldwide is the human immunodeficiency virus(HIV)and acquired immune deficiency syndrome(AIDS)pandemic.HIV has a disproportionately negative impact on key populations.Strong leadership,effective communication,and sound science are necessary for public health emergency(PHE)responses to be successful.These three PHE response pllars are also essential for bridging the HIV response gap among key populations in the setting of restrictive laws.In this review,we explored the importance of these three pillars of successful PHEs responses,and how they are essential to closing the gap in the HIV response among key populations.Leaders must make decisions and instil a sense of authority in the populace during PHEs to foster trust and confidence.Leaders should base their choices on scientific evidence.Effective communication during PHEs should be proactive,polite,imaginative,innovative,and constructive.To address gaps in the HIV response among key populations,leaders must create a supportive environment for effective communication and scientific research,communication should be used to raise awareness of HIV and to dispel stigma and discrimination,while science should provide evidence of efficacy and effectiveness of interventions amongkey populations. 展开更多
关键词 Public health emergencies LEADERSHIP COMMUNICATION SCIENCE Key populations HIV response
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1990—2019年中国结直肠癌疾病负担变化趋势分析 被引量:1
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作者 周海茸 王巍巍 +1 位作者 罗鹏飞 洪忻 《肿瘤防治研究》 CAS 2024年第2期115-120,共6页
目的 分析1990-2019年中国结直肠癌疾病负担变化趋势及定量估计影响因素。方法 利用2019年全球疾病负担研究结果,分析1990-2019年我国结直肠癌疾病负担以及危险因素归因疾病负担的变化情况,并采用Gupta分解法定量估算人口增长、老龄化... 目的 分析1990-2019年中国结直肠癌疾病负担变化趋势及定量估计影响因素。方法 利用2019年全球疾病负担研究结果,分析1990-2019年我国结直肠癌疾病负担以及危险因素归因疾病负担的变化情况,并采用Gupta分解法定量估算人口增长、老龄化、年龄别患病率和疾病严重程度的改变对疾病负担变化的贡献。结果 1990-2019年我国结直肠癌标化伤残调整寿命年率(DALY rates)呈上升趋势,2019年DALY值较1990年增长了191.12%,其中34.54%可归因于人口增长、111.36%可归因于人口老龄化、77.56%可归因于年龄别患病率的增加、-32.34%归因于疾病严重程度。牛奶摄入不足位列2019年结直肠癌的首要危险因素,其次是谷物摄入不足和钙摄入不足;11种可改变的危险因素中,高BMI所致标化DALY率较1990年增幅最大(225.15%),年均增长4.14%,纤维素摄入不足所致标化DALY率较1990年降幅最大(-44.23%),年均减少2.00%。结论 1990-2019年,我国结直肠癌疾病负担呈上升趋势,人口老龄化是导致结直肠癌疾病负担增长最主要的原因,卫生行政部门应采取相应措施应对老龄化带来的不利影响。 展开更多
关键词 结直肠癌 疾病负担 人口老龄化 危险因素
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人口迁移流动与城镇化发展战略任务 被引量:1
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作者 任远 《北京行政学院学报》 北大核心 2024年第1期107-117,共11页
本世纪以来,特别是2010年以来,我国人口迁移流动和城镇化表现出的特点是:流动人口数量继续增长,人口流动向东部地区尤其是东南沿海地区转移,人口迁移流动存在“南强北弱”和“北人南迁”趋势,人口城镇化水平继续提高和中西部地区城镇化... 本世纪以来,特别是2010年以来,我国人口迁移流动和城镇化表现出的特点是:流动人口数量继续增长,人口流动向东部地区尤其是东南沿海地区转移,人口迁移流动存在“南强北弱”和“北人南迁”趋势,人口城镇化水平继续提高和中西部地区城镇化增长更快,人口更明显地向特大城市和超大城市集聚,带来超大、特大城市数量增加,并在此基础上带动若干核心城市都市圈和城市群发展等。结合人口迁移流动态势,直面我国城镇化发展进程所面临的战略任务,提出应加快推进农业转移人口和流动人口的市民化,在城镇化过程中实现更加平衡的国家发展,以及在不同地区实践多样性和因地制宜的城镇化发展。 展开更多
关键词 人口迁移流动 城镇化 市民化 农业转移人口
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番茄潜叶蛾种群定殖与种群重建及延续能力研究
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作者 张桂芬 万坤 +9 位作者 潘梦妮 王龙 黄聪 王玉生 张毅波 冼晓青 杨念婉 桂富荣 刘万学 万方浩 《中国农业科学》 CAS CSCD 北大核心 2024年第3期514-524,共11页
【背景】番茄潜叶蛾(Tuta absoluta)是一种对番茄等作物最具毁灭性危害的世界检疫性害虫,2017年首次在我国西北新疆伊犁的露地番茄发现,2018年又在我国西南云南临沧的保护地番茄发生,目前已快速传播至我国20余个省级区域。【目的】以成... 【背景】番茄潜叶蛾(Tuta absoluta)是一种对番茄等作物最具毁灭性危害的世界检疫性害虫,2017年首次在我国西北新疆伊犁的露地番茄发现,2018年又在我国西南云南临沧的保护地番茄发生,目前已快速传播至我国20余个省级区域。【目的】以成虫为对象在室内笼罩条件下,研究明确番茄潜叶蛾的种群定殖、种群重建及延续能力。【方法】每笼接入不同数量(2、4、6、8、10头)的番茄潜叶蛾成虫(性比1:1),通过评价其产卵量和幼虫孵化率,研究繁殖体数量对番茄潜叶蛾种群定殖能力的影响;以1对成虫(2头,性比1:1)为起始繁殖体数量,通过种群数量动态监测、虫态(龄期)个体数量占比及丰富度指数R评价,研究番茄潜叶蛾的种群重建和延续能力。【结果】以5个繁殖体数量(2、4、6、8、10头,性比1:1)接入番茄潜叶蛾成虫,各繁殖体数量的总计产卵量分别为93.1、194.9、271.3、311.5和400.2粒,差异显著;平均单雌产卵量分别为93.1、97.4、90.4、77.9和80.0粒,差异显著,且繁殖体数量为1♀:1♂、2♀:2♂和3♀:3♂的平均单雌产卵量明显高于4♀:4♂和5♀:5♂;此外,在5个繁殖体起始数量处理中,卵孵化为幼虫的比率均比较高,为91.3%—92.7%;综合分析结果显示,种群定殖能力大小依次为5♀:5♂>3♀:3♂>4♀:4♂>2♀:2♂>1♀:1♂。1对(2头,性比1:1)番茄潜叶蛾成虫即可重新建立种群,约90 d(3个世代)后种群即可达到稳定状态。在168 d(约5个世代)的种群重建和种群延续过程中,仅在最初的0—91 d范围观察到3个较为明显的种群发生高峰(世代),高峰日总计虫量(蛹未予计入)较起始繁殖体数量分别增加77.8、60.5和60.1倍,其中,成虫数量分别增加6.4、4.1和7.7倍;之后,各虫态(卵、1—4龄幼虫、成虫)同时发生,世代重叠现象明显,种群数量趋于稳定并波动增长,总计种群数量持续稳定在96.6—140.6头,不同虫态(龄期)个体数量占比在16.67%上下波动,丰富度指数R稳定在1.011—1.094。【结论】番茄潜叶蛾1对成虫即具有较高的生殖与存活能力,传入的起始繁殖体数量越大,番茄潜叶蛾成功定殖的可能性越大;1头雌虫和1头雄虫即可重新建立种群并使种群得以稳定延续。1对成虫的传入即具有较大的入侵风险并产生足够多的后代以满足种群延续和扩张,因此,在番茄潜叶蛾防控工作中,应加强对该虫的监测预警,并力争在其点片发生期予以灭除。 展开更多
关键词 番茄潜叶蛾 繁殖体数量 种群定殖 种群重建 种群延续 虫态(龄期)丰富度
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改进群体智能算法的无线传感器网络覆盖优化 被引量:1
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作者 贾润亮 张海玉 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期155-166,共12页
为解决无线传感器网络(Wireless Sensor Networks,WSN)节点分布不均和随机部署中的低覆盖率问题,该文提出一种改进群体智能算法的无线传感器网络覆盖优化算法,即改进的黑猩猩优化和哈里斯鹰优化的混合优化算法(Improved Chimp Optimizat... 为解决无线传感器网络(Wireless Sensor Networks,WSN)节点分布不均和随机部署中的低覆盖率问题,该文提出一种改进群体智能算法的无线传感器网络覆盖优化算法,即改进的黑猩猩优化和哈里斯鹰优化的混合优化算法(Improved Chimp Optimization and Harris Hawk Optimization Algorithm,ICHHO).该算法首先对黑猩猩优化算法(Chimpanzee Optimization Algorithm,ChOA)进行改进,使用Levy Flight来改善其探索阶段,然后设计一个更新的公式来计算猎物逃逸能量,作为开发和探索之间的选择因素.传感器节点随机部署后,将ICHHO在传感器节点上执行,按照改进策略更新个体位置信息,计算相应的适应程度,找到最优传感器位置,并根据传感器概率模型确定网络最优覆盖率.仿真结果验证了ICHHO对于解决WSN覆盖问题的适用性,与其他优化算法的对比结果显示,ICHHO在提高覆盖率方面优于其他算法. 展开更多
关键词 无线传感器网络 黑猩猩优化 哈里斯鹰优化 覆盖率 群体智能算法
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巴里坤县城镇与牧区人群血浆致动脉粥样硬化指数与尿酸水平的相关性分析
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作者 玛依娜·卡哈尔 张蓓 +2 位作者 朱语秋 杜满茜 孙玉萍 《检验医学与临床》 CAS 2024年第11期1558-1561,1567,共5页
目的分析巴里坤县城镇与牧区人群血浆致动脉粥样硬化指数(AIP)与尿酸水平的相关性。方法选取2018年9月至2021年3月在新疆维吾尔自治区哈密市巴里坤县医院进行体检的1388例体检人群(城镇人群675例,牧区人群713例)作为研究对象。按照是否... 目的分析巴里坤县城镇与牧区人群血浆致动脉粥样硬化指数(AIP)与尿酸水平的相关性。方法选取2018年9月至2021年3月在新疆维吾尔自治区哈密市巴里坤县医院进行体检的1388例体检人群(城镇人群675例,牧区人群713例)作为研究对象。按照是否患有高尿酸血症分别将城镇人群和牧区人群分为城镇高尿酸血症组(285例)、城镇对照组(390例)和牧区高尿酸血症组(141例)、牧区对照组(572例)。比较城镇高尿酸血症组和城镇对照组临床资料,以及牧区高尿酸血症组和牧区对照组临床资料。采用Spearman相关分析城镇高尿酸血症组和牧区高尿酸血症组的AIP与尿酸水平的相关性。采用多因素Logistic回归分析城镇人群及牧区人群发生高尿酸血症的危险因素。结果城镇高尿酸血症组体质量指数(BMI)、舒张压、AIP、尿酸、总胆固醇(TC)、甘油三酯(TG)水平高于城镇对照组,腰围大于城镇对照组,差异均有统计学意义(P<0.05)。牧区高尿酸血症组BMI、AIP、尿酸、TG水平高于牧区对照组,年龄、腰围大于牧区对照组,TC、高密度脂蛋白胆固醇(HDL-C)水平低于牧区对照组,差异均有统计学意义(P<0.05)。Spearman相关分析结果显示,城镇高尿酸血症组和牧区高尿酸血症组的AIP与尿酸水平均呈正相关(r_(s)=0.384、0.405,P<0.05)。多因素Logistic回归分析结果显示,BMI升高、腰围增大是城镇人群发生高尿酸血症的独立危险因素(P<0.05)。AIP升高,HDL-C、TC水平降低,腰围、年龄增大是牧区人群发生高尿酸血症的独立危险因素(P<0.05)。结论城镇与牧区人群AIP与尿酸水平密切相关,对预测该地区人群高尿酸血症的发生具有重要意义。 展开更多
关键词 城镇人群 牧区人群 血浆致动脉粥样硬化指数 尿酸 相关性
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