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Southeast China (southeast + china)
Selected AbstractsGENE FLOW AND SPECIES DELIMITATION: A CASE STUDY OF TWO PINE SPECIES WITH OVERLAPPING DISTRIBUTIONS IN SOUTHEAST CHINAEVOLUTION, Issue 8 2010Yong Feng Zhou Species delimitation detected by molecular markers is complicated by introgression and incomplete lineage sorting between species. Recent modeling suggests that fixed genetic differences between species are highly related to rates of intraspecific gene flow. However, it remains unclear whether such differences are due to high levels of intraspecific gene flow overriding the spread of introgressed alleles or favoring rapid lineage sorting between species. In pines, chloroplast (cp) and mitochondrial (mt) DNAs are normally paternally and maternally inherited, respectively, and thus their relative rates of intraspecific gene flow are expected to be high and low, respectively. In this study, we used two pine species with overlapping geographical distributions in southeast China, P. massoniana and P. hwangshanensis, as a model system to examine the association between organelle gene flow and variation within and between species. We found that cpDNA variation across these two pine species is more species specific than mtDNA variation and almost delimits taxonomic boundaries. The shared mt/cp DNA genetic variation between species shows no bias in regard to parapatric versus allopatric species' distributions. Our results therefore support the hypothesis that high intraspecific gene flow has accelerated cpDNA lineage sorting between these two pine species. [source] Middle Pleistocene human cranium from Tangshan (Nanjing), Southeast China: A new reconstruction and comparisons with Homo erectus from Eurasia and AfricaAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2005Wu Liu Abstract The morphology and affinities of early and middle Pleistocene Homo erectus in East Asia have been explored since the late nineteenth century. A fragmentary hominid cranium (Nanjing no.1) recovered in Tangshan near Nanjing, China bears directly on these issues. In the present study, the morphological features of Nanjing no.1 are described and compared with Homo erectus from both Eurasia and Africa. Our results indicate that this middle Pleistocene hominid fossil should be referred to as Homo erectus. The sharing of typical Homo erectus features with African and European counterparts demonstrates that Homo erectus is a widely distributed lineage that evolved during the million years after its Pliocene origins. The differences between Nanjing no.1 and Zhoukoudian suggest certain level of regional variation in East Asian Homo erectus. Am J Phys Anthropol, 2005. © 2004 Wiley-Liss, Inc. [source] Refined Geographic Distribution of the Oriental ALDH2*504Lys (nee 487Lys) VariantANNALS OF HUMAN GENETICS, Issue 3 2009Hui Li Summary Mitochondrial aldehyde dehydrogenase (ALDH2) is one of the most important enzymes in human alcohol metabolism. The oriental ALDH2*504Lys variant functions as a dominant negative, greatly reducing activity in heterozygotes and abolishing activity in homozygotes. This allele is associated with serious disorders such as alcohol liver disease, late onset Alzheimer disease, colorectal cancer, and esophageal cancer, and is best known for protection against alcoholism. Many hundreds of papers in various languages have been published on this variant, providing allele frequency data for many different populations. To develop a highly refined global geographic distribution of ALDH2*504Lys, we have collected new data on 4,091 individuals from 86 population samples and assembled published data on a total of 80,691 individuals from 366 population samples. The allele is essentially absent in all parts of the world except East Asia. The ALDH2*504Lys allele has its highest frequency in Southeast China, and occurs in most areas of China, Japan, Korea, Mongolia, and Indochina with frequencies gradually declining radially from Southeast China. As the indigenous populations in South China have much lower frequencies than the southern Han migrants from Central China, we conclude that ALDH2*504Lys was carried by Han Chinese as they spread throughout East Asia. Esophageal cancer, with its highest incidence in East Asia, may be associated with ALDH2*504Lys because of a toxic effect of increased acetaldehyde in the tissue where ingested ethanol has its highest concentration. While the distributions of esophageal cancer and ALDH2*504Lys do not precisely correlate, that does not disprove the hypothesis. In general the study of fine scale geographic distributions of ALDH2*504Lys and diseases may help in understanding the multiple relationships among genes, diseases, environments, and cultures. [source] Bacterial diversity in various coastal mariculture ponds in Southeast China and in diseased eels as revealed by culture and culture-independent molecular techniquesAQUACULTURE RESEARCH, Issue 9 2010Yonghui Zeng Abstract Mariculture ponds are widely distributed in Chinese coasts and have become a threat to the health of coastal ecosystems. In order to improve our understanding on the microbial composition in mariculture environments, we sampled a variety of ponds farming different animals or plants around the Dongshan Island and Xiamen Island in Southeast China and isolated cultures from the tissues of diseased eels. Analysis by polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE), clone library and direct culturing methods revealed highly diverse bacterial communities in these samples. Bacterial communities in the Dongshan samples were dominated by Alphaproteobacteria, Gammaproteobacteria and Bacteroidetes. The Gracilaria verrucosa pond harbours the most abundant species (20 DGGE bands), followed by Epinephelus diacanthus pond (18 bands), Haliotis diversicolor supertexta pond I (18 bands) and Penaeus vannamei pond (11 bands). In comparison with surface waters, Penacus orientalis pond sediment showed a much more complex bacterial community, from which only sequences affiliated with Deltaproteobacteria, Firmicutes, Acidobacteria and candidate phylum TM6 were found. Bacterial cultures in diseased eels were closely related to two pathogenic genera, Aeromonas in Gammaproteobacteria and Bacillus, in Firmicutes. Clones affiliated with another two genera, Escherichia and Vibrio, that have pathogenic potentials were also identified. Phylogenetic analysis of a total of 131 sequences showed that 48.9% of the sequences were clustered into Gammaproteobacteria and formed the most abundant group, followed by Alphaproteobacteria (19.1%), Firmicutes (7.6%), Bacteroidetes (5.3%), Deltaproteobacteria (5.3%), Actinobacteria (4.6%), Chloroplast (3.8%), Acidobacteria (2.3%), Cyanobacteria (1.5%), Betaproteobacteria (0.7%) and TM6 (0.7%). 43.7% (28/64) of the phylogenetic clusters cannot be classified into any known genus and 44.3% (58/131) of the sequences show <95% similarity to public database records, suggesting that abundant novel species exist in mariculture ponds. Gathering bacterial diversity data in mariculture ponds and diseased fish is meaningful for the prevention and control of fish diseases and for the improvement of our understanding of microbial ecology in a pond environment. [source] Secular trends of hypospadias prevalence and factors associated with it in southeast China during 1993,2005BIRTH DEFECTS RESEARCH, Issue 6 2010Lei Jin Abstract BACKGROUND The aim of this study is to describe the prevalence of hypospadias and its time trends during 1993,2005 in southeast China, and to explore the potential risk factors. METHODS The study population included all male live and still births (at least 20 weeks of gestation) in 11 cities and counties in Jiangsu and Zhejiang Provinces in Southeast China born during January 1, 1993, through December 31, 2005. RESULTS Overall prevalence of hypospadias was 5.8 per 10,000 male births and presented an increasing trend during 1993,2005 (with , of 3.94, p = 0.047). Prevalence of coronal hypospadias and those with unknown sites increased from 1.7 and 0.3 per 10,000 male births in 1993 to 3.6 and 1.4 per 10,000 male births in 2005, respectively (with , of 7.29 and 9.05, p = 0.007 and p = 0.002, respectively), but prevalence of perineal hypospadias decreased (with , of 7.13, p = 0.008). Maternal fever during first trimester, birth of twins or more children, and year of birth were independent risk factors for hypospadias, with odds ratios of 4.14 (95% CI, 1.32,12.83), 3.37 (95% CI, 1.73,6.58), and 1.04 (95% CI, 1.00,1.08), respectively, after adjusting for confounding factors with multivariable logistic regression analysis. CONCLUSIONS Prevalence of hypospadias increased during 1993,2005 in the two provinces in southeast China. Maternal fever in the first trimester and birth of twins or more children are associated with the risk for hypospadias. Birth Defects Research (Part A), 2010. © 2010 Wiley-Liss, Inc. [source] Petrology and Geochemistry of the Huangshan Granitic Intrusion in Anhui Province, Southeast China: Implications for Petrogenesis and GeodynamicsACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 3 2010Shu ZHANG Abstract: The Huangshan granitic intrusion in Anhui province, SE China, is tectonically located at the southeastern boundary of the Yangtze Block. Based on the contact relation and the petrography, the Huangshan granitic intrusion can be divided into four stages, from early to late, medium-grained monzogranite, coarse-grained porphyric granite, fine-medium grained porphyric granite, and fine-coarse grained granite. All rocks from the Huangshan granitic intrusion display similar petrological and geochemical characteristics, i.e. relatively high SiO2 (>75%) and alkali (7.85%,8.59%), low CaO(<1%), high Fe-number (FeOT/(MgO+FeOT) = 0.93,0.97) and A/CNK (atomic Al/(Ca+Na+K)) = 1.04,1.19. They are also enriched in rare earth elements (REE, except for Eu, with a total REE contents ranging from 116 ppm to 421 ppm), high strength field elements such as Zr, Hf, Nb, but depleted in Ba, Sr and Ni. The 10 000×Ga/Al ratios are higher than 2.6, which are consistent with the A-type granitoids. Based on the classification diagrams proposed by Eby, the Huangshan granite can be classified into the A2 group, which is usually believed to be formed under an extensional tectonic setting. Their Nd isotopic compositions suggest that the primary magmas of the Huangshan granite are predominantly derived from the Proterozoic andesitic rocks in the region, and this conclusion is also supported by REE modeling. The systemic investigations on the geochemistry of the Huangshan granitic intrusion can provide significant implications for the understanding of the petrogenesis and the geodynamic regime of southeastern China during the Late-Mesozoic. [source] Neoproterozoic Tectonic Setting of Southeast China: New Constraints from SHRIMP U-Pb Zircon Ages and Petrographic Studies on the Mamianshan GroupACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 2 2010Ganguo WU Abstract: Precambrian tectonic history of Zhejiang, Fujian, and Jiangxi provinces of south China is important for understanding the tectonic evolution of South China but its magmatic activity, petrogenesis, stratigraphic sequence of the Mamianshan Group is still strongly controversial. Here we present new sensitive high resolution ion micro-probe (SHRIMP) U-Pb zircon geochronological data for the Mamianshan Group and petrographical data to constrain the tectonic framework of the regions. Our results showed that the SHRIMP U-Pb zircon age of green schists of the Dongyan Formation is 796.544.3 Ma, the Daling Formation is 756.2±7.2 Ma, and mica-quartz schist of the Longbeixi Formation is 825.5±9.8 Ma. These data indicate that the Mamianshan Group was formed not in the Mesoproterozoic, but in the Neoproterozoic and its stratigraphic sequences should be composed of Longbeixi, Dongyan, and Daling Formations from the bottom to the top. Rocks from this Group, from Zhejiang, Fujian and Jiangxi provinces, constituted the upper basement of the Cathaysia Block that overlay the lower basement of the Mayuan Group. Detailed petrographic studies demonstrate that the amphibole schists of the Dongyan Formation in the Mamianshan Group were formed within an intra-arc rift setting rather than a continental rift as previously suggested. Rather, this island-arc type formation was developed by collision and/or subduction between various blocks resulting from the breakup of the supercontinent Rodinia at c.850,750 Ma. The Zhuzhou conglomerate, distributed near Dikou Town, Jian'ou City, Fujian Province and previously considered as evidence of the Mesoproterozoic Dikou movement, is shown here not to be the basal conglomerate above the angular unconformity between the upper and lower basements. Our conclusions have important implications for understanding the Precambrian tectonics of South China. [source] PAX9 polymorphisms and susceptibility to sporadic tooth agenesis: a case,control study in southeast ChinaEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2008Yongchu Pan Tooth agenesis is one of the most common developmental disorders in humans. The PAX9 gene, which plays an important role in odontogenesis, is associated with familial and sporadic tooth agenesis. A case,control study was performed in 102 subjects with tooth agenesis (cases) and 116 healthy controls. We genotyped four PAX9 gene polymorphisms using a polymerase chain reaction,restriction fragment length polymorphism (PCR-RFLP) assay. The allele and genotype frequencies of the four polymorphisms were not significantly different between the controls and the subjects with tooth agenesis. Similar results were observed in a subgroup analysis of test subjects only with mandibular incisor agenesis. Further analysis showed no significant difference in the haplotype distribution between the controls and the subjects with tooth agenesis or mandibular incisor agenesis. However, we found that the AGGC haplotype was associated with a decreased risk of tooth agenesis, compared with the most common haplotype, AGCC (odds ratio, 0.14; 95% confidence interval: 0.00,0.95). These results suggest that the four PAX9 polymorphisms alone have a non-significant main effect on the risk of tooth agenesis but that the AGGC haplotype may have a protective effect associated with a decreased risk of tooth agenesis. [source] GENE FLOW AND SPECIES DELIMITATION: A CASE STUDY OF TWO PINE SPECIES WITH OVERLAPPING DISTRIBUTIONS IN SOUTHEAST CHINAEVOLUTION, Issue 8 2010Yong Feng Zhou Species delimitation detected by molecular markers is complicated by introgression and incomplete lineage sorting between species. Recent modeling suggests that fixed genetic differences between species are highly related to rates of intraspecific gene flow. However, it remains unclear whether such differences are due to high levels of intraspecific gene flow overriding the spread of introgressed alleles or favoring rapid lineage sorting between species. In pines, chloroplast (cp) and mitochondrial (mt) DNAs are normally paternally and maternally inherited, respectively, and thus their relative rates of intraspecific gene flow are expected to be high and low, respectively. In this study, we used two pine species with overlapping geographical distributions in southeast China, P. massoniana and P. hwangshanensis, as a model system to examine the association between organelle gene flow and variation within and between species. We found that cpDNA variation across these two pine species is more species specific than mtDNA variation and almost delimits taxonomic boundaries. The shared mt/cp DNA genetic variation between species shows no bias in regard to parapatric versus allopatric species' distributions. Our results therefore support the hypothesis that high intraspecific gene flow has accelerated cpDNA lineage sorting between these two pine species. [source] Tracking neolithic interactions in southeast China: Evidence from stone adze geochemistryGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 8 2005Zhengfu Guo The authors conducted a sourcing study of stone adzes recently excavated from the Damaoshan site on Dongshan Island, Fujian province, China. They used XRF, ICP-MS, and petrographic thin-section techniques for geochemical and petrographic analysis of six stone adzes from the site and three geological samples from Dongshan Island. The chemical data of these samples compared with other lavas in Fujian, Zhejiang, Penghu, and Taiwan suggest that the Damaoshan people imported stone raw materials either from the Penghu Archipelago in the Taiwan Strait or from the Niutoushan area on the Fujian coast. This indicates that exchange networks along the southeast coast of China, and possibly spanning the Taiwan Strait, had developed as early as 4300,5000 yr B. P. © 2005 Wiley Periodicals, Inc. [source] Recent expansion of highly pathogenic avian influenza H5N1: a critical reviewIBIS, Issue 2 2007M. GAUTHIER-CLERC Wild birds, particularly waterfowl, are a key element of the viral ecology of avian influenza. Highly pathogenic avian influenza (HPAI) virus, subtype H5N1, was first detected in poultry in November 1996 in southeast China, where it originated. The virus subsequently dispersed throughout most of Asia, and also to Africa and Europe. Despite compelling evidence that the virus has been dispersed widely via human activities that include farming, and marketing of poultry, migratory birds have been widely considered to be the primary source of its global dispersal. Here we present a critical examination of the arguments both for and against the role of migratory birds in the global dispersal of HPAI H5N1. We conclude that, whilst wild birds undoubtedly contribute to the local spread of the virus in the wild, human commercial activities, particularly those associated with poultry, are the major factors that have determined its global dispersal. [source] Diabetes, pre-diabetes and associated risks on Minnesota code-indicated major electrocardiogram abnormality among Chinese: a cross-sectional diabetic study in Fujian province, southeast ChinaOBESITY REVIEWS, Issue 4 2009L. Lin Summary The goal of this study was to determine the prevalence of diabetes mellitus (DM), impaired glucose regulation (IGR) and related metabolic disorders (overweight, obesity and hypertension) in a Chinese population (20,74 years old). An additional goal was to investigate the relationship between glucose metabolism and the Minnesota code-indicated major abnormal electrocardiogram (MA-ECG). There were 3960 individuals selected from urban and rural areas of Fujian, China from July 2007 to May 2008 by multistage-stratified sampling. Ultimately, data from 3208 subjects (20,74 years old) were analysed (including physical measurements, blood biochemical analysis, oral glucose tolerance test and 12-lead resting ECG). According to World Health Organization diagnostic criteria, the prevalence rates of DM and IGR were 9.51% (male, 10.08%; female, 9.14%) and 14.40% (male, 14.48%; female, 14.35%) respectively. Newly diagnosed DM was found in 53.44% of the diabetic subjects. Based on the 2000 China census, the age-standardized prevalence rates of DM and IGR were 7.19% (male, 7.74%; female, 6.61%) and 11.96 % (male, 12.35%; female, 11.56%) respectively. The age-standardized prevalence rates of DM and IGR in urban areas (7.74% and 12.97% respectively) were slightly but no significantly higher than in rural areas (6.67%, 10.86%). The prevalence rates of overweight, obesity and hypertension were 25.50%, 3.52% and 28.52% respectively (age- and sex- standardized rates: 23.69%, 3.02 % and 22.45 %). After adjusting for other confounding risk factors, multiple logistic regression analysis showed that DM and impaired glucose tolerance were independent risk factors for MA-ECG. Non-diabetic subjects with increased 30-min plasma glucose (PG) after an oral glucose load had a higher risk of MA-ECG after adjusting for other risk factors, especially in those with normal glucose tolerance but with 30-min PG , 7.8 mmol L,1 (odds ratio = 1.371 [1.055,1.780]). The prevalence rates of DM and IGR as well as other metabolic disorders have increased dramatically in the last decade in China, especially in rural areas, with many undiagnosed cases of DM. Even slightly elevated PG levels may predict early cardiovascular events. [source] Fertility and Distorted Sex Ratios in a Rural Chinese County: Culture, State, and PolicyPOPULATION AND DEVELOPMENT REVIEW, Issue 4 2003Rachel Murphy This article explores how gender bias in population policies interacts with local culture to reinforce distortions in sex ratios among infants and young children in rural China. It argues that population policies introduce new sources of inequality into local culture while, conversely, gender inequalities embedded in local culture influence formal population policy and practice. Applying an institutional approach to the study of an agricultural county in Jiangxi province, southeast China, the analysis identifies four ways in which an interplay between gender bias in policy and culture produces gendered fertility outcomes: (1) the creation of gendered official categories such as "daughter-only households"; (2) a male bias embedded in local government; (3) the use of local gender norms in state pedagogy; and (4) the reworking or subverting of official norms in ways that reinforce gender inequalities in local reproductive culture. The article concludes that despite indications of contestation of village patriarchy, discrimination against daughters is likely to persist. [source] Phylogenetic analysis and species identification of popular shrimp species in southeast China using the first internally transcribed spacer of ribosomal DNAAQUACULTURE RESEARCH, Issue 11 2009Zhigang Wu Abstract The ribosomal DNA internally transcribed spacer 1 (ITS1) was investigated in the search for an appropriate genetic marker that was suitable for phylogenetic study and species identification of eight major exported shrimp species in southeast China. Using the selected primers, the amplified ITS1 sequences exhibited a high degree of length polymorphisms, ranging from 448 bp in Metapenaeopsis dalei to 1491 bp in Macrobrachium nipponense. Many microsatellite loci were found at the 5, end and in the middle region of ITS1, which seemed to be associated with intragenomic sequence variation among samples of the same species. This variation might obscure the phylogenetic relationship between some shrimp populations, but the separation of five Penaeus species was well supported. In combination with polymerase chain reaction-restriction fragment length polymerism methods analysis, ITS1 sequences from shrimp species belonging to different families and genera could also be easily discernable. The results suggested that ITS1 was highly variable among different shrimp groups and could be an appropriate marker for species identification and molecular systematic studies. [source] Secular trends of hypospadias prevalence and factors associated with it in southeast China during 1993,2005BIRTH DEFECTS RESEARCH, Issue 6 2010Lei Jin Abstract BACKGROUND The aim of this study is to describe the prevalence of hypospadias and its time trends during 1993,2005 in southeast China, and to explore the potential risk factors. METHODS The study population included all male live and still births (at least 20 weeks of gestation) in 11 cities and counties in Jiangsu and Zhejiang Provinces in Southeast China born during January 1, 1993, through December 31, 2005. RESULTS Overall prevalence of hypospadias was 5.8 per 10,000 male births and presented an increasing trend during 1993,2005 (with , of 3.94, p = 0.047). Prevalence of coronal hypospadias and those with unknown sites increased from 1.7 and 0.3 per 10,000 male births in 1993 to 3.6 and 1.4 per 10,000 male births in 2005, respectively (with , of 7.29 and 9.05, p = 0.007 and p = 0.002, respectively), but prevalence of perineal hypospadias decreased (with , of 7.13, p = 0.008). Maternal fever during first trimester, birth of twins or more children, and year of birth were independent risk factors for hypospadias, with odds ratios of 4.14 (95% CI, 1.32,12.83), 3.37 (95% CI, 1.73,6.58), and 1.04 (95% CI, 1.00,1.08), respectively, after adjusting for confounding factors with multivariable logistic regression analysis. CONCLUSIONS Prevalence of hypospadias increased during 1993,2005 in the two provinces in southeast China. Maternal fever in the first trimester and birth of twins or more children are associated with the risk for hypospadias. Birth Defects Research (Part A), 2010. © 2010 Wiley-Liss, Inc. [source] | ||||||||||||||||