The airborne pollen grains of Afyon have been studied for a two_year period (1999-2000) with a Durham sampler. A total of 14 367 pollen grains belonging to 40 taxa have been identified and recorded with some unidentif...The airborne pollen grains of Afyon have been studied for a two_year period (1999-2000) with a Durham sampler. A total of 14 367 pollen grains belonging to 40 taxa have been identified and recorded with some unidentified ones. Of them, 6 732 were identified in 1999 and 7 635 in 2000. Of the total pollen grains, 69.67% were arboreal, 26.64% non_arboreal and 3.68 % unidentified. The majority of the investigated pollen grains were from Pinus, Gramineae, Cupressaceae, Platanus , Chenopodiaceae/Amaranthaceae, Quercus, Ailanthus, Moraceae, Juglans , Salix, Cedrus and Rosaceae. The highest level of pollen grains was in May.展开更多
Urticaceae Juss.is a large cosmopolitan family and taxonomically difficult group,partly because it encompasses a broad range of morphological diversity and many of the diagnostic characters（e.g.flower,achene.stipule,...Urticaceae Juss.is a large cosmopolitan family and taxonomically difficult group,partly because it encompasses a broad range of morphological diversity and many of the diagnostic characters（e.g.flower,achene.stipule,bract）require a microscope for accurate determination.Meanwhile,most Uriiceae species have stinging hairs which make them more difficult to collect and identify.As a result,the infra-familial classification of Urticaceae has been controversial for more than a century.A research group led by Prof.展开更多
Invasive hybridization and introgression pose a serious threat to the persistence of many native species. Understand- ing the effects of hybridization on native populations （e.g., fitness consequences） requires nume...Invasive hybridization and introgression pose a serious threat to the persistence of many native species. Understand- ing the effects of hybridization on native populations （e.g., fitness consequences） requires numerous species-diagnostic loci dis- tributed genome-wide. Here we used RAD sequencing to discover thousands of single-nucleotide polymorphisms （SNPs） that are diagnostic between rainbow trout （RBT, Oncorhynchus mykiss）, the world＇s most widely introduced fish, and native westslope cutthroat trout （WCT, （9. clarkii lewisi） in the northern Rocky Mountains, USA. We advanced previous work that identified 4,914 species-diagnostic loci by using longer sequence reads （100 bp vs. 60 bp） and a larger set of individuals （n = 84）. We sequenced RAD libraries for individuals from diverse sampling sources, including native populations of WCT and hatchery broodstocks of WCT and RBT. We also took advantage of a newly released reference genome assembly for RBT to align our RAD loci. In total, we discovered 16,788 putatively diagnostic SNPs, 10,267 of which we mapped to anchored chromosome locations on the RBT genome. A small portion of previously discovered putative diagnostic loci （325 of 4,914） were no longer diagnostic （i.e., fixed between species） based on our wider survey of non-hybridized RBT and WCT individuals. Our study suggests that RAD loci mapped to a draft genome assembly could provide the marker density required to identify genes and chromosomal regions in- fluencing selection in admixed populations of conservation concern and evolutionary interest [Current Zoology 61 （1）： 146-154, 2015].展开更多
The covariate-specific receiver operating characteristic(ROC) curve is an important tool for evaluating the classification accuracy of a diagnostic test when it is associated with certain covariates. In this paper,a w...The covariate-specific receiver operating characteristic(ROC) curve is an important tool for evaluating the classification accuracy of a diagnostic test when it is associated with certain covariates. In this paper,a weighted Wilcoxon estimator is constructed for estimating this curve under the framework of location-scale model for the test result. The asymptotic normality is established, both for the regression parameter estimator and the estimator for the covariate-specific ROC curve at a fixed false positive point. Simulation results show that the Wilcoxon estimator compares favorably to its main competitors in terms of the standard error, especially when outliers exist in the covariates. As an illustration, the new procedure is applied to the dementia data from the national Alzheimer's coordinating center.展开更多
文摘The airborne pollen grains of Afyon have been studied for a two_year period (1999-2000) with a Durham sampler. A total of 14 367 pollen grains belonging to 40 taxa have been identified and recorded with some unidentified ones. Of them, 6 732 were identified in 1999 and 7 635 in 2000. Of the total pollen grains, 69.67% were arboreal, 26.64% non_arboreal and 3.68 % unidentified. The majority of the investigated pollen grains were from Pinus, Gramineae, Cupressaceae, Platanus , Chenopodiaceae/Amaranthaceae, Quercus, Ailanthus, Moraceae, Juglans , Salix, Cedrus and Rosaceae. The highest level of pollen grains was in May.
文摘Urticaceae Juss.is a large cosmopolitan family and taxonomically difficult group,partly because it encompasses a broad range of morphological diversity and many of the diagnostic characters（e.g.flower,achene.stipule,bract）require a microscope for accurate determination.Meanwhile,most Uriiceae species have stinging hairs which make them more difficult to collect and identify.As a result,the infra-familial classification of Urticaceae has been controversial for more than a century.A research group led by Prof.
文摘Invasive hybridization and introgression pose a serious threat to the persistence of many native species. Understand- ing the effects of hybridization on native populations （e.g., fitness consequences） requires numerous species-diagnostic loci dis- tributed genome-wide. Here we used RAD sequencing to discover thousands of single-nucleotide polymorphisms （SNPs） that are diagnostic between rainbow trout （RBT, Oncorhynchus mykiss）, the world＇s most widely introduced fish, and native westslope cutthroat trout （WCT, （9. clarkii lewisi） in the northern Rocky Mountains, USA. We advanced previous work that identified 4,914 species-diagnostic loci by using longer sequence reads （100 bp vs. 60 bp） and a larger set of individuals （n = 84）. We sequenced RAD libraries for individuals from diverse sampling sources, including native populations of WCT and hatchery broodstocks of WCT and RBT. We also took advantage of a newly released reference genome assembly for RBT to align our RAD loci. In total, we discovered 16,788 putatively diagnostic SNPs, 10,267 of which we mapped to anchored chromosome locations on the RBT genome. A small portion of previously discovered putative diagnostic loci （325 of 4,914） were no longer diagnostic （i.e., fixed between species） based on our wider survey of non-hybridized RBT and WCT individuals. Our study suggests that RAD loci mapped to a draft genome assembly could provide the marker density required to identify genes and chromosomal regions in- fluencing selection in admixed populations of conservation concern and evolutionary interest [Current Zoology 61 （1）： 146-154, 2015].
基金supported by National Natural Science Foundation of China (Grant Nos. 11401561 and 11301031)
文摘The covariate-specific receiver operating characteristic(ROC) curve is an important tool for evaluating the classification accuracy of a diagnostic test when it is associated with certain covariates. In this paper,a weighted Wilcoxon estimator is constructed for estimating this curve under the framework of location-scale model for the test result. The asymptotic normality is established, both for the regression parameter estimator and the estimator for the covariate-specific ROC curve at a fixed false positive point. Simulation results show that the Wilcoxon estimator compares favorably to its main competitors in terms of the standard error, especially when outliers exist in the covariates. As an illustration, the new procedure is applied to the dementia data from the national Alzheimer's coordinating center.
