Lignin metabolism plays a pivotal role in plant defense against pathogens and is always positively correlated as a response to pathogen infection. Thus, understanding resistance genes against plant pathogens depends o...Lignin metabolism plays a pivotal role in plant defense against pathogens and is always positively correlated as a response to pathogen infection. Thus, understanding resistance genes against plant pathogens depends on a genetic analysis of the lignin response. This study used eight Upland cotton lines to construct a multi-parent advanced generation intercross(MAGIC) population(n=280), which exhibited peculiar characteristics from the convergence of various alleles coding for advantageous traits. In order to measure the lignin response to Verticillium wilt(LRVW), the artificial disease nursery(ADN) and rotation nursery(RN) were prepared for MAGIC population planting in four environments. The stem lignin contents were collected, and the LRVW was measured with the lignin value of ADN/RN in each environment, which showed significant variations. We employed 9 323 high-quality single-nucleotide polymorphism(SNP) markers obtained from the Cotton-SNP63K array for genotyping the MAGIC population. The SNPs were distributed through the whole genome with 4.78 SNP/Mb density, ranging from 1.14(ChrA06) to 10.08(ChrD08). In addition, a genome-wide association study was performed using a Mixed Linear Model(MLM) for LRVW. Three stable quantitative trait loci(QTLs), qLRVW-A04, qLRVW-A10, and qLRVW-D05, were identified in more than two environments. Two key candidate genes, Ghi_D05G01046 and Ghi_D05G01221, were selected within the QTLs through the combination of variations in the coding sequence, induced expression patterns, and function annotations. Both genes presented nonsynonymous mutations in coding regions and were strongly induced by Verticillium dahliae. Ghi_D05G01046 encodes a leucine-rich extensin(LRx) protein involved in Arabidopsis cell wall biosynthesis and organization. Ghi_D05G01221 encodes a transcriptional co-repressor novel interactor of novel interactor of jasmonic acid ZIM-domain(JAZ–NINJA), which functions in the jasmonic acid(JA) signaling pathway. In summary, the study creates valuable genetic resources for breeding and QTL mapping and opens up a new perspective to uncover the genetic basis of VW resistance in Upland cotton.展开更多
The sizes of Astyanax mexicanus blind cavefish populations of North-East Mexico are demographic parameters of great importance for investigating a variety of ecological,evolutionary,and conservation issues.However,few...The sizes of Astyanax mexicanus blind cavefish populations of North-East Mexico are demographic parameters of great importance for investigating a variety of ecological,evolutionary,and conservation issues.However,few estimates have been obtained.For these mobile animals living in an environment difficult to explore as a whole,methods based on capture-mark-recapture are appropriate,but their feasibility and interpretation of results depend on several assumptions that must be carefully examined.Here,we provide evidence that minimally invasive genetic identification from captures at different time intervals(three days and three years)can give insights into cavefish population size dynamics as well as other important demographic parameters of interest.We also provide tools to calibrate sampling and genotyping efforts necessary to reach a given level of precision.Our results suggest that the El Pachón cave population is currently very small,of an order of magnitude of a few hundreds of individuals,and is distributed in a relatively isolated area.The probable decline in population size in the El Pachón cave since the last census in 1971 raises serious conservation issues.展开更多
The identification of loci and markers associated with milled grain appearance traits is essential for breeding high-yielding and good-quality rice variety.To detect stable loci for these characteristics,grain length(...The identification of loci and markers associated with milled grain appearance traits is essential for breeding high-yielding and good-quality rice variety.To detect stable loci for these characteristics,grain length(GL),grain width(GW),grain length/width(GLW),chalkiness degree(CD),chalky-grain rate(CR)and translucency degree(TD)of 378 rice lines were evaluated in three seasons.These lines were derived from a multi-parent advanced generation intercross(MAGIC)population.展开更多
AIM:To estimate post-war burdens of trachomatous trichiasis(TT)and multi-level risk factors among displaced population in Raya Kobo districts,implication for urgent action.METHODS:A community-based cross-sectional stu...AIM:To estimate post-war burdens of trachomatous trichiasis(TT)and multi-level risk factors among displaced population in Raya Kobo districts,implication for urgent action.METHODS:A community-based cross-sectional study was conducted among 603 participants from randomly selected 14 displaced slums in the Raya Kobo district.The data was collected from February 16th to March 30th,2023.Study participants were selected using the multistage sampling technique.A structured questionnaire and ophthalmic loupe with×2.5 magnificence were used to collect from participants.Multi-level binary logistic regression was used to determine associated factors with TT infection.Adjusted odds ratio(AOR)with 95%confidence interval(CI)were claimed for the strength of association at P<0.05.RESULTS:We recruited 602(99.9%)participants for the final analysis.From the total,126(20.9%)and 98(16.3%,95%CI:13.5%-19.4%)participants were diagnosed with active trachoma&TT infection,respectively.Being age≥45y(AOR=7.9,95%CI:2.4-25.3),having multiple eye infections(AOR=2.73,95%CI:1.47-5.29),poor wealth index(AOR=9.2;95%CI:2.7-23.7)and twice face washing per day(AOR=0.082,95%CI:0.03-0.21)has identified as individual as factors for TT infection.Whereas,distance between clean water source≥10 km(AOR=6.5,95%CI:3.9-31.3),and latrine availability(AOR=0.35,95%CI:0.21-0.58)were the two community-level factors associated with TT infections.CONCLUSION:The high prevalence of TT infection post-war throughout the study districts indicates a need for urgent clinical intervention in addition to rapid scaling up surgery,antibiotics,facial cleanliness,and environmental improvement(SAFE)strategies,strategy for high-risk population.Age≥45y,distance from the clean water source,poor wealth indexes,and eye infection are identified to be risk factors for TT infection.Furthermore,community-level preventative factors for TT infection are found as latrine availability and face washing practice.展开更多
[Objective] The changes of fungi in different soil layers and sand dunes of artificial vegetation areas in Ningxia Shapotou during different times were studied. [Method]The number of soil fungi in different soil layer...[Objective] The changes of fungi in different soil layers and sand dunes of artificial vegetation areas in Ningxia Shapotou during different times were studied. [Method]The number of soil fungi in different soil layers at same plot and in same soil layer at different plots were changed significantly.The quantitative distribution of fungi was the most in Cuiliugou but the fewest in quicksand among all soil types.[Result] The quantity of soil fungi in grasslands was varied in different soil layers at the same sample and in the same soil layer at different sample plots. The quantity of fungi from different soil types distributed mostly in Cuiliugou, a natural desert steppe, but little in quicksand. The species and quantity of fungi in CuiLiugou was the most in different types of sand-fixing lands. [Conclusion] The quantity of soil fungi in artificial vegetation areas raises with the increase of sand-fixing ages, The enhancement of vegetation construction and artificial management measures in inland is helpful for improving present situation of desertification.展开更多
A new breeding population of Mandarin Duck (Aix gaIericulata, Linnaeus) was first recorded in 2003 in Jiao- tanzhuang-Hehekou region of Pingshan county, Hebei Province, China. Recently, the gradually increasing popu...A new breeding population of Mandarin Duck (Aix gaIericulata, Linnaeus) was first recorded in 2003 in Jiao- tanzhuang-Hehekou region of Pingshan county, Hebei Province, China. Recently, the gradually increasing population indicates that there are suitable breeding habitats (such as foraging habitats and nesting sites) for Mandarin Duck. However, these habitats are always close to human disturbances, which are the potential risk for their population. Therefore, it is urgent to put forward an applicable protection strategy, in order to strengthen the public awareness for this unprotected population.展开更多
The scalar of Japanese yew (Taxus cuspidata) population and the relationship between individual distribution and site factors were analyzed according to investigating data in 74 sample belts with a total sampled are...The scalar of Japanese yew (Taxus cuspidata) population and the relationship between individual distribution and site factors were analyzed according to investigating data in 74 sample belts with a total sampled area of 436.872 hm2 in Muling Nature Reserve. The result showed that the distribution rules of Japanese yew population were correlated to elevation, slope position, slope aspect and slope gradient. The optimal distribution range in elevation for the natural Japanese yew population is at the attitudes of 700-800 m. The amounts of Japanese yew individuals on shady slope were more than those on sunny slope. On top slope and mid-slope, the individual amounts of Japanese yew are more than those on toe slope. Most of Japanese yew individuals occurred on slope gradient of less than 15. The scalar of the population was decreased with the slope gradient increasing.展开更多
Mutations in GJB2 gene are the most frequently found mutations in patients with nonsyndromic hearing impairment. However, the spectrum and prevalence of mutations in this gene vary among different ethnic groups. In Ch...Mutations in GJB2 gene are the most frequently found mutations in patients with nonsyndromic hearing impairment. However, the spectrum and prevalence of mutations in this gene vary among different ethnic groups. In China, 30,000 infants are born with congenital hearing impairment annually. In order to provide appropriate genetic testing and counseling to the families, we investigated the molecular etiology of nonsyndromic deafness in 103 unrelated school children attending Nantong School for the Deaf and Mute in Jiangsu Province, China. The coding exon of the GJB2 gene was PCR amplified and sequenced. Sixty two GJB2 mutant alleles were identified in 35.9% (37/103) of the patients. Twenty five patients carried two pathogenic mutations and 12 patients carried one mutant allele. The 235delC was the most common mutation accounting for 69.4% (43/62) of GJB2 mutant alleles. The GJB2 mutant alleles accounted for 30.1% (62/206) of all chromosomes responsible for nonsyndromic hearing impairment. Testing of the 3 most prevalent deleterious frame shift mutations in this cohort detected 100% of all GJB2 mutant alleles. These results demonstrate that an effective genetic testing of GJB2 gene for patients and families with nonsyndromic hearing impairment is possible.展开更多
BACKGROUND: It is of significance for single nucleotide polymorphisms (SNPs), a difference of rank, which exists widely in biology, genetics and other fields. OBJECTIVE: To detect polymorphism sites in exon-4 of p...BACKGROUND: It is of significance for single nucleotide polymorphisms (SNPs), a difference of rank, which exists widely in biology, genetics and other fields. OBJECTIVE: To detect polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene of healthy people in Han nationality in Zhejiang province. DESIGN: Simple random sampling. SETTING: Department of Surgery of the 118 Hospital of Chinese PLA.PARTICIPANTS: A total of 80 healthy people in Han nationality were selected from hospitals in Zhejiang province from August 2005 to January 2006. There were 43 males and 37 females aged from 3 to 78 years with the mean age of 39.5 years, and all subjects were consent. DNA which was used in genetic analysis was selected from peripheral venous blood of all subjects and maintained at -20℃.METHODS: Polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene were detected with directly DNA sequencing technique. MAIN OUTCOME MEASURES : Polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene of healthy people in Han nationality in Zhejiang province. RESULTS: A total of 80 samples were involved in the final analysis. SNPs sites were found at the 119^th base of exon-4 of p53 gene (the 72^nd codon of p53 gene), the 670^th base of upper start codon in promotor of Fas gene (Fas-670), and the 995^th base of intron-7 of Fas gene, especially SNPs in the 995^th base of intron-7 pf Fas gene, i.e. C→A transversion, was a new site.CONCLUSION : One unknown SNPs site is discovered in intron-7 of Fas gene of people in Han nationality in Zhejiang province. This study also proves that the 72^nd codon exists in p53 gene and the -670 polymorphism site exists in promotor of Fas gene.展开更多
In this paper, we discuss and analyze theoretically probeabsorption-amplification response in a four-level coherent atomic system with vacuum-inducedcoherence via changing the sign of the parameter f, with f denoting ...In this paper, we discuss and analyze theoretically probeabsorption-amplification response in a four-level coherent atomic system with vacuum-inducedcoherence via changing the sign of the parameter f, with f denoting the ratio of a pair of dipolemoments associated with a doublet of closely upper hypernne sublevels. We find that the amplitude ofthe probe amplification for the case f = -1 can be about one order of magnitude larger than thatachievable for the case f = 1. In addition, with respect to the case f = -1 the probe amplificationcan be maintained all the time with weak incoherent pumping for a wide range of the probe detuning.展开更多
In this paper, before the implementation of ecological laboratory experiments, the population interaction dynamics of an algae-fish system were studied mathematically and numerically. The purpose of this study was to ...In this paper, before the implementation of ecological laboratory experiments, the population interaction dynamics of an algae-fish system were studied mathematically and numerically. The purpose of this study was to explore how filter-feeding fish population affects the growth dynamics of the algae population. Mathematically theoretical works have been pursuing the investigation of some key conditions for stability of the equilibrium and existence of Hopf bifurcation. Numerical simulation works have been parsing the discovery of the growth dynamics of the algae population in view of population interaction dynamics, which in turn could prove the feasibility of the theoretical derivation and reveal the relationship between filter-feeding fish abundance and algal biomass in fish-drift algae communiyua. Furthermore, it was successful to show that the filter-feeding fish population may be a crucial factor in controlling the proliferation of the algae population, which could also directly grasp the evolution of community dynamics. All these results were expected to be useful in the study of community dynamics and laboratory elimination experiment of the algae population.展开更多
In many fields such as signal processing,machine learning,pattern recognition and data mining,it is common practice to process datasets containing huge numbers of features.In such cases,Feature Selection(FS)is often i...In many fields such as signal processing,machine learning,pattern recognition and data mining,it is common practice to process datasets containing huge numbers of features.In such cases,Feature Selection(FS)is often involved.Meanwhile,owing to their excellent global search ability,evolutionary computation techniques have been widely employed to the FS.So,as a powerful global search method and calculation fast than other EC algorithms,PSO can solve features selection problems well.However,when facing a large number of feature selection,the efficiency of PSO drops significantly.Therefore,plenty of works have been done to improve this situation.Besides,many studies have shown that an appropriate population initialization can effectively help to improve this problem.So,basing on PSO,this paper introduces a new feature selection method with filter-based population.The proposed algorithm uses Principal Component Analysis(PCA)to measure the importance of features first,then based on the sorted feature information,a population initialization method using the threshold selection and the mixed initialization is proposed.The experiments were performed on several datasets and compared to several other related algorithms.Experimental results show that the accuracy of PSO to solve feature selection problems is significantly improved after using proposed method.展开更多
[Objective] This study aimed to conduct genetic analysis on agronomic traits of doubled haploid population in tobacco. [Method] Main agronomic traits of DH population in tobacco were investigated, including plant heig...[Objective] This study aimed to conduct genetic analysis on agronomic traits of doubled haploid population in tobacco. [Method] Main agronomic traits of DH population in tobacco were investigated, including plant height, effective number of leaves, lumbar leaf length, lumbar leaf width, intermodal distance and pericaulome length. Based on the estimation of skewness coefficient and kurtosis coefficient of Hongda x Hicks Broad Leaf populations, the number of gene pairs was calculated. [Result] The number of gene pairs controlling plant height (topping plant height and natural plant height) is 10.20 and 10.80, respectively; the number of gene pairs con- trolling leaf number (effective number of leaves and natural number of leaves) is 6.21 and 6.25, respectively; the number of gene pairs controlling pericaulome length, intermodal distance, lumbar leaf length and lumbar leaf width is 8.51, 15.30, 20.36 and 17.45, respectively. [Conclusion] This study revealed the characteristics of genetic variation of tobacco traits, which provided theoretical basis for the breeding of new varieties.展开更多
Sideband manipulation of population inversion in a three-level A atomic configuration is investigated theoretically. Compared with the case of a nearly monochromatic field, a population inversion between an excited st...Sideband manipulation of population inversion in a three-level A atomic configuration is investigated theoretically. Compared with the case of a nearly monochromatic field, a population inversion between an excited state and a ground state has been found in a wide sideband intensity range by increasing the difference in frequency between three components. Furthermore, the population inversion can be controlled by the sum of the relative phases of the sideband components of the trichromatic pump field with respective to the phase of the central component. Changing the sum phase from 0 to π, the population inversion between the excited state and the ground state can increase within nearly half of the sideband intensity range. At the same time, the sideband intensity range that corresponds to the system exhibiting inversion ρ00 〉 ρ11 also becomes wider evidently.展开更多
With the development of society, people's life consciousness is also changing, China town features becomes a hot topic at present. At the same time, "the provisions of the 13th Five-Year" plan clearly played a posi...With the development of society, people's life consciousness is also changing, China town features becomes a hot topic at present. At the same time, "the provisions of the 13th Five-Year" plan clearly played a positive role in pushing forward the construction of the town's characteristics, to create a set of characteristics, industry, town charm in one. With the development of reform and opening-up Chinese, feature of the town is not only exist as an important carrier of urban population centers in the form of evacuation, to a certain extent, it also played a "cohesion", integration into the world economy through the industrial chain. The development mode of Chinese characteristics of the town, according to the situation of China is very suitable for the party Can alleviate the "urban diseases" this problem, on the other hand, can prevent the "empty countryside" this problem, the construction of Chinese feature of the town, to a certain extent also can promote and promote the further development of urbanization, the economic and social advancement is also very important and irreplaceable role.展开更多
基金financed by the National Natural Science Foundation of China (31760402 and 31771844)the Innovation Leadership Program in Sciences and Technologies for Young and Middle-aged Scientists of Xinjiang Production and Construction Corps, China (2019CB027)。
文摘Lignin metabolism plays a pivotal role in plant defense against pathogens and is always positively correlated as a response to pathogen infection. Thus, understanding resistance genes against plant pathogens depends on a genetic analysis of the lignin response. This study used eight Upland cotton lines to construct a multi-parent advanced generation intercross(MAGIC) population(n=280), which exhibited peculiar characteristics from the convergence of various alleles coding for advantageous traits. In order to measure the lignin response to Verticillium wilt(LRVW), the artificial disease nursery(ADN) and rotation nursery(RN) were prepared for MAGIC population planting in four environments. The stem lignin contents were collected, and the LRVW was measured with the lignin value of ADN/RN in each environment, which showed significant variations. We employed 9 323 high-quality single-nucleotide polymorphism(SNP) markers obtained from the Cotton-SNP63K array for genotyping the MAGIC population. The SNPs were distributed through the whole genome with 4.78 SNP/Mb density, ranging from 1.14(ChrA06) to 10.08(ChrD08). In addition, a genome-wide association study was performed using a Mixed Linear Model(MLM) for LRVW. Three stable quantitative trait loci(QTLs), qLRVW-A04, qLRVW-A10, and qLRVW-D05, were identified in more than two environments. Two key candidate genes, Ghi_D05G01046 and Ghi_D05G01221, were selected within the QTLs through the combination of variations in the coding sequence, induced expression patterns, and function annotations. Both genes presented nonsynonymous mutations in coding regions and were strongly induced by Verticillium dahliae. Ghi_D05G01046 encodes a leucine-rich extensin(LRx) protein involved in Arabidopsis cell wall biosynthesis and organization. Ghi_D05G01221 encodes a transcriptional co-repressor novel interactor of novel interactor of jasmonic acid ZIM-domain(JAZ–NINJA), which functions in the jasmonic acid(JA) signaling pathway. In summary, the study creates valuable genetic resources for breeding and QTL mapping and opens up a new perspective to uncover the genetic basis of VW resistance in Upland cotton.
基金supported by a CNRS MITI (Mission pour les Initiatives Transverses et Interdisciplinaires) grant “Expérimentation en Milieux Extrêmes” to S.R.collaborative grants from Agence Nationale de la Recherche (BLINDTEST)Institut Diversité Ecologie et Evolution du Vivant to S.R. and D.C
文摘The sizes of Astyanax mexicanus blind cavefish populations of North-East Mexico are demographic parameters of great importance for investigating a variety of ecological,evolutionary,and conservation issues.However,few estimates have been obtained.For these mobile animals living in an environment difficult to explore as a whole,methods based on capture-mark-recapture are appropriate,but their feasibility and interpretation of results depend on several assumptions that must be carefully examined.Here,we provide evidence that minimally invasive genetic identification from captures at different time intervals(three days and three years)can give insights into cavefish population size dynamics as well as other important demographic parameters of interest.We also provide tools to calibrate sampling and genotyping efforts necessary to reach a given level of precision.Our results suggest that the El Pachón cave population is currently very small,of an order of magnitude of a few hundreds of individuals,and is distributed in a relatively isolated area.The probable decline in population size in the El Pachón cave since the last census in 1971 raises serious conservation issues.
基金supported by the earmarked fund for China Agriculture Research System(Grant No.CARS-01)Young Elite Scientists Sponsorship Program by China Association for Science and Technology(Grant No.2020QNRC001)Hunan Academy of Agricultural Sciences Scientific and Technological Innovation Project,China(Grant No.2017JC10)。
文摘The identification of loci and markers associated with milled grain appearance traits is essential for breeding high-yielding and good-quality rice variety.To detect stable loci for these characteristics,grain length(GL),grain width(GW),grain length/width(GLW),chalkiness degree(CD),chalky-grain rate(CR)and translucency degree(TD)of 378 rice lines were evaluated in three seasons.These lines were derived from a multi-parent advanced generation intercross(MAGIC)population.
文摘AIM:To estimate post-war burdens of trachomatous trichiasis(TT)and multi-level risk factors among displaced population in Raya Kobo districts,implication for urgent action.METHODS:A community-based cross-sectional study was conducted among 603 participants from randomly selected 14 displaced slums in the Raya Kobo district.The data was collected from February 16th to March 30th,2023.Study participants were selected using the multistage sampling technique.A structured questionnaire and ophthalmic loupe with×2.5 magnificence were used to collect from participants.Multi-level binary logistic regression was used to determine associated factors with TT infection.Adjusted odds ratio(AOR)with 95%confidence interval(CI)were claimed for the strength of association at P<0.05.RESULTS:We recruited 602(99.9%)participants for the final analysis.From the total,126(20.9%)and 98(16.3%,95%CI:13.5%-19.4%)participants were diagnosed with active trachoma&TT infection,respectively.Being age≥45y(AOR=7.9,95%CI:2.4-25.3),having multiple eye infections(AOR=2.73,95%CI:1.47-5.29),poor wealth index(AOR=9.2;95%CI:2.7-23.7)and twice face washing per day(AOR=0.082,95%CI:0.03-0.21)has identified as individual as factors for TT infection.Whereas,distance between clean water source≥10 km(AOR=6.5,95%CI:3.9-31.3),and latrine availability(AOR=0.35,95%CI:0.21-0.58)were the two community-level factors associated with TT infections.CONCLUSION:The high prevalence of TT infection post-war throughout the study districts indicates a need for urgent clinical intervention in addition to rapid scaling up surgery,antibiotics,facial cleanliness,and environmental improvement(SAFE)strategies,strategy for high-risk population.Age≥45y,distance from the clean water source,poor wealth indexes,and eye infection are identified to be risk factors for TT infection.Furthermore,community-level preventative factors for TT infection are found as latrine availability and face washing practice.
文摘[Objective] The changes of fungi in different soil layers and sand dunes of artificial vegetation areas in Ningxia Shapotou during different times were studied. [Method]The number of soil fungi in different soil layers at same plot and in same soil layer at different plots were changed significantly.The quantitative distribution of fungi was the most in Cuiliugou but the fewest in quicksand among all soil types.[Result] The quantity of soil fungi in grasslands was varied in different soil layers at the same sample and in the same soil layer at different sample plots. The quantity of fungi from different soil types distributed mostly in Cuiliugou, a natural desert steppe, but little in quicksand. The species and quantity of fungi in CuiLiugou was the most in different types of sand-fixing lands. [Conclusion] The quantity of soil fungi in artificial vegetation areas raises with the increase of sand-fixing ages, The enhancement of vegetation construction and artificial management measures in inland is helpful for improving present situation of desertification.
基金supported by Natural Science Foun-dation of Hebei Province (D2006000701, C2007000247)Doctoral Fund of Hebei Normal University (L2008B11)
文摘A new breeding population of Mandarin Duck (Aix gaIericulata, Linnaeus) was first recorded in 2003 in Jiao- tanzhuang-Hehekou region of Pingshan county, Hebei Province, China. Recently, the gradually increasing population indicates that there are suitable breeding habitats (such as foraging habitats and nesting sites) for Mandarin Duck. However, these habitats are always close to human disturbances, which are the potential risk for their population. Therefore, it is urgent to put forward an applicable protection strategy, in order to strengthen the public awareness for this unprotected population.
基金This work was supported by Northeast Forestry University fund Program from Science and Technology Department of Heilongjiang Province (LC05C14)
文摘The scalar of Japanese yew (Taxus cuspidata) population and the relationship between individual distribution and site factors were analyzed according to investigating data in 74 sample belts with a total sampled area of 436.872 hm2 in Muling Nature Reserve. The result showed that the distribution rules of Japanese yew population were correlated to elevation, slope position, slope aspect and slope gradient. The optimal distribution range in elevation for the natural Japanese yew population is at the attitudes of 700-800 m. The amounts of Japanese yew individuals on shady slope were more than those on sunny slope. On top slope and mid-slope, the individual amounts of Japanese yew are more than those on toe slope. Most of Japanese yew individuals occurred on slope gradient of less than 15. The scalar of the population was decreased with the slope gradient increasing.
基金This work was supported by the Chinese National Nature Science Foundation research Grant 30572015Beijing Nature Science Foundation research Grant 7062062.
文摘Mutations in GJB2 gene are the most frequently found mutations in patients with nonsyndromic hearing impairment. However, the spectrum and prevalence of mutations in this gene vary among different ethnic groups. In China, 30,000 infants are born with congenital hearing impairment annually. In order to provide appropriate genetic testing and counseling to the families, we investigated the molecular etiology of nonsyndromic deafness in 103 unrelated school children attending Nantong School for the Deaf and Mute in Jiangsu Province, China. The coding exon of the GJB2 gene was PCR amplified and sequenced. Sixty two GJB2 mutant alleles were identified in 35.9% (37/103) of the patients. Twenty five patients carried two pathogenic mutations and 12 patients carried one mutant allele. The 235delC was the most common mutation accounting for 69.4% (43/62) of GJB2 mutant alleles. The GJB2 mutant alleles accounted for 30.1% (62/206) of all chromosomes responsible for nonsyndromic hearing impairment. Testing of the 3 most prevalent deleterious frame shift mutations in this cohort detected 100% of all GJB2 mutant alleles. These results demonstrate that an effective genetic testing of GJB2 gene for patients and families with nonsyndromic hearing impairment is possible.
文摘BACKGROUND: It is of significance for single nucleotide polymorphisms (SNPs), a difference of rank, which exists widely in biology, genetics and other fields. OBJECTIVE: To detect polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene of healthy people in Han nationality in Zhejiang province. DESIGN: Simple random sampling. SETTING: Department of Surgery of the 118 Hospital of Chinese PLA.PARTICIPANTS: A total of 80 healthy people in Han nationality were selected from hospitals in Zhejiang province from August 2005 to January 2006. There were 43 males and 37 females aged from 3 to 78 years with the mean age of 39.5 years, and all subjects were consent. DNA which was used in genetic analysis was selected from peripheral venous blood of all subjects and maintained at -20℃.METHODS: Polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene were detected with directly DNA sequencing technique. MAIN OUTCOME MEASURES : Polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene of healthy people in Han nationality in Zhejiang province. RESULTS: A total of 80 samples were involved in the final analysis. SNPs sites were found at the 119^th base of exon-4 of p53 gene (the 72^nd codon of p53 gene), the 670^th base of upper start codon in promotor of Fas gene (Fas-670), and the 995^th base of intron-7 of Fas gene, especially SNPs in the 995^th base of intron-7 pf Fas gene, i.e. C→A transversion, was a new site.CONCLUSION : One unknown SNPs site is discovered in intron-7 of Fas gene of people in Han nationality in Zhejiang province. This study also proves that the 72^nd codon exists in p53 gene and the -670 polymorphism site exists in promotor of Fas gene.
文摘In this paper, we discuss and analyze theoretically probeabsorption-amplification response in a four-level coherent atomic system with vacuum-inducedcoherence via changing the sign of the parameter f, with f denoting the ratio of a pair of dipolemoments associated with a doublet of closely upper hypernne sublevels. We find that the amplitude ofthe probe amplification for the case f = -1 can be about one order of magnitude larger than thatachievable for the case f = 1. In addition, with respect to the case f = -1 the probe amplificationcan be maintained all the time with weak incoherent pumping for a wide range of the probe detuning.
文摘In this paper, before the implementation of ecological laboratory experiments, the population interaction dynamics of an algae-fish system were studied mathematically and numerically. The purpose of this study was to explore how filter-feeding fish population affects the growth dynamics of the algae population. Mathematically theoretical works have been pursuing the investigation of some key conditions for stability of the equilibrium and existence of Hopf bifurcation. Numerical simulation works have been parsing the discovery of the growth dynamics of the algae population in view of population interaction dynamics, which in turn could prove the feasibility of the theoretical derivation and reveal the relationship between filter-feeding fish abundance and algal biomass in fish-drift algae communiyua. Furthermore, it was successful to show that the filter-feeding fish population may be a crucial factor in controlling the proliferation of the algae population, which could also directly grasp the evolution of community dynamics. All these results were expected to be useful in the study of community dynamics and laboratory elimination experiment of the algae population.
基金This work is supported by National Natural Science Foundation of China(Grant Nos.61876089,61403206)by Science and Technology Program of Ministry of Housing and Urban-Rural Development(2019-K-141)+1 种基金by Entrepreneurial Team of Sponge City(2017R02002)by Innovation and entrepreneurship training program for College Students。
文摘In many fields such as signal processing,machine learning,pattern recognition and data mining,it is common practice to process datasets containing huge numbers of features.In such cases,Feature Selection(FS)is often involved.Meanwhile,owing to their excellent global search ability,evolutionary computation techniques have been widely employed to the FS.So,as a powerful global search method and calculation fast than other EC algorithms,PSO can solve features selection problems well.However,when facing a large number of feature selection,the efficiency of PSO drops significantly.Therefore,plenty of works have been done to improve this situation.Besides,many studies have shown that an appropriate population initialization can effectively help to improve this problem.So,basing on PSO,this paper introduces a new feature selection method with filter-based population.The proposed algorithm uses Principal Component Analysis(PCA)to measure the importance of features first,then based on the sorted feature information,a population initialization method using the threshold selection and the mixed initialization is proposed.The experiments were performed on several datasets and compared to several other related algorithms.Experimental results show that the accuracy of PSO to solve feature selection problems is significantly improved after using proposed method.
基金Supported by Project of Yunnan Tobacco Company(2010YN02,2011YN04)~~
文摘[Objective] This study aimed to conduct genetic analysis on agronomic traits of doubled haploid population in tobacco. [Method] Main agronomic traits of DH population in tobacco were investigated, including plant height, effective number of leaves, lumbar leaf length, lumbar leaf width, intermodal distance and pericaulome length. Based on the estimation of skewness coefficient and kurtosis coefficient of Hongda x Hicks Broad Leaf populations, the number of gene pairs was calculated. [Result] The number of gene pairs controlling plant height (topping plant height and natural plant height) is 10.20 and 10.80, respectively; the number of gene pairs con- trolling leaf number (effective number of leaves and natural number of leaves) is 6.21 and 6.25, respectively; the number of gene pairs controlling pericaulome length, intermodal distance, lumbar leaf length and lumbar leaf width is 8.51, 15.30, 20.36 and 17.45, respectively. [Conclusion] This study revealed the characteristics of genetic variation of tobacco traits, which provided theoretical basis for the breeding of new varieties.
基金Project supported by the National Natural Science Foundation of China (Grant No 60708008)the Project of Academic Leaders in Shanghai,China (Grant No 07XD14030)the Knowledge Innovation Program of the Chinese Academy of Sciences
文摘Sideband manipulation of population inversion in a three-level A atomic configuration is investigated theoretically. Compared with the case of a nearly monochromatic field, a population inversion between an excited state and a ground state has been found in a wide sideband intensity range by increasing the difference in frequency between three components. Furthermore, the population inversion can be controlled by the sum of the relative phases of the sideband components of the trichromatic pump field with respective to the phase of the central component. Changing the sum phase from 0 to π, the population inversion between the excited state and the ground state can increase within nearly half of the sideband intensity range. At the same time, the sideband intensity range that corresponds to the system exhibiting inversion ρ00 〉 ρ11 also becomes wider evidently.
文摘With the development of society, people's life consciousness is also changing, China town features becomes a hot topic at present. At the same time, "the provisions of the 13th Five-Year" plan clearly played a positive role in pushing forward the construction of the town's characteristics, to create a set of characteristics, industry, town charm in one. With the development of reform and opening-up Chinese, feature of the town is not only exist as an important carrier of urban population centers in the form of evacuation, to a certain extent, it also played a "cohesion", integration into the world economy through the industrial chain. The development mode of Chinese characteristics of the town, according to the situation of China is very suitable for the party Can alleviate the "urban diseases" this problem, on the other hand, can prevent the "empty countryside" this problem, the construction of Chinese feature of the town, to a certain extent also can promote and promote the further development of urbanization, the economic and social advancement is also very important and irreplaceable role.