South China (south + china)

Distribution by Scientific Domains
Distribution within Earth and Environmental Science

Terms modified by South China

  • south china plate
  • south china sea

  • Selected Abstracts

    Morpho-anatomy of the lobopod Magadictyon cf. haikouensis from the Early Cambrian Chengjiang Lagerstätte, South China

    ACTA ZOOLOGICA, Issue 4 2007
    Jianni Liu
    Abstract Magadictyon haikouensis (Luo and Hu, 1999) from the Early Cambrian Chengjiang Lagerstätte, an incomplete specimen of a large lobopod with strong appendages, has been regarded as related to the lobopods Microdictyon and Onychodictyon. Newly discovered complete specimens of Magadictyon cf. haikouensis (found by the Early Life Institute field team) show that the taxon, in addition to its strong appendages with appendicules, also had a head bearing similar caecum-like structures to those of the arthropod Naraoia and Chelicerate, ,Peytoia'-like mouthparts and frontal appendages. Because of their similarity, the caecum-like structures of Magadictyon cf. haikouensis are considered to be homologous with those of stem-group arthropods. The ,Peytoia'-like mouthparts and the frontal appendages are similar to those of the AOPK (Anomalocaris,Opabinia,Pambdelurion,Kerygmachela) group. In addition, the appendages with appendicules show that Magadictyon cf. haikouensis is closely related to Onychodictyon. Therefore, Magadictyon cf. haikouensis is regarded here as a rare transitional form between lobopods and arthropods. Besides, together with other lobopods, the morphology of Magadictyon cf. haikouensis demonstrates that the Cambrian lobopods appear to have been diverse and not particularly closely related to one another, and do not seem to represent a monophyletic clade. [source]

    An attenuation model for distant earthquakes

    Adrian Chandler
    Abstract Large magnitude earthquakes generated at source,site distances exceeding 100km are typified by low-frequency (long-period) seismic waves. Such induced ground shaking can be disproportionately destructive due to its high displacement, and possibly high velocity, shaking characteristics. Distant earthquakes represent a potentially significant safety hazard in certain low and moderate seismic regions where seismic activity is governed by major distant sources as opposed to nearby (regional) background sources. Examples are parts of the Indian sub-continent, Eastern China and Indo-China. The majority of ground motion attenuation relationships currently available for applications in active seismic regions may not be suitable for handling long-distance attenuation, since the significance of distant earthquakes is mainly confined to certain low to moderate seismicity regions. Thus, the effects of distant earthquakes are often not accurately represented by conventional empirical models which were typically developed from curve-fitting earthquake strong-motion data from active seismic regions. Numerous well-known existing attenuation relationships are evaluated in this paper, to highlight their limitations in long-distance applications. In contrast, basic seismological parameters such as the Quality factor (Q -factor) could provide a far more accurate representation for the distant attenuation behaviour of a region, but such information is seldom used by engineers in any direct manner. The aim of this paper is to develop a set of relationships that provide a convenient link between the seismological Q -factor (amongst other factors) and response spectrum attenuation. The use of Q as an input parameter to the proposed model enables valuable local seismological information to be incorporated directly into response spectrum predictions. The application of this new modelling approach is demonstrated by examples based on the Chi-Chi earthquake (Taiwan and South China), Gujarat earthquake (Northwest India), Nisqually earthquake (region surrounding Seattle) and Sumatran-fault earthquake (recorded in Singapore). Field recordings have been obtained from these events for comparison with the proposed model. The accuracy of the stochastic simulations and the regression analysis have been confirmed by comparisons between the model calculations and the actual field observations. It is emphasized that obtaining representative estimates for Q for input into the model is equally important.Thus, this paper forms part of the long-term objective of the authors to develop more effective communications across the engineering and seismological disciplines. Copyright © 2003 John Wiley & Sons, Ltd. [source]

    Contaminant pattern and bioaccumulation of legacy and emerging organhalogen pollutants in the aquatic biota from an e-waste recycling region in South China

    Ying Zhang
    Abstract Legacy pollutants, polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), and some emerging organhalogen pollutants, such as polybrominated diphenyl ethers (PBDEs), hexabromobenzene (HBB), pentabromotoluene (PBT), 2,3,4,5,6-pentabromoethyl benzene (PBEB), 1,2- bis (2,4,6-tribromophenoxy) ethane (BTBPE), and dechlorane plus (DP), were detected in an aquatic food chain (invertebrates and fish) from an e-waste recycling region in South China. Polychlorinated biphenyls, DDTs, PBDEs, and HBB were detected in more than 90% of the samples, with respective concentrations ranging from not detected (ND),32,000,ng/g lipid weight, ND,850,ng/g lipid weight, 8 to 1,300,ng/g lipid weight, and 0.28 to 240,ng/g lipid weight. Pentabromotoluene, PBEB, BTBPE, and DP were also quantifiable in collected samples with a concentration range of ND,40,ng/g lipid weight. The elevated levels of PCBs and PBDEs in the organisms, compared with those in non-e-waste regions in South China, suggest that these two kinds of pollutants derived mainly from e-waste recycling practices. Hexabromobenzene was significantly correlated with PBDEs, implying that HBB come from the release of e-waste along with PBDEs and/or the pyrolysis of BDE209. Most of the compounds whose trophic magnification factor (TMF) could be calculated were found to biomagnify (TMF > 1). Hexabromobenzene was also found, for the first time, to biomagnify in the present food web, with a TMF of 2.1. Environ. Toxicol. Chem. 2010;29:852,859. © 2010 SETAC [source]

    High-resolution Lopingian (Late Permian) timescale of South China

    GEOLOGICAL JOURNAL, Issue 2-3 2010
    Shu-Zhong Shen
    Abstract The Lopingian represents the last epoch of the Palaeozoic Era and is bracketed by two severe biotic mass extinctions associated with dramatic environmental changes. The Lopingian Epoch lasted about 7 millions years and was also bracketed by large volcanic eruptions with the Emeishan volcanics at the base and the Siberian traps at the top. Considerable data have accumulated recently and in this paper we attempt to summarize these findings in a high-resolution Lopingian (Late Permian) timescale that integrates currently available multiple biostratigraphic, isotope chemostratigraphic, geochronologic and magnetostratigraphic data. In South China at least 13 conodont zones, multiple polarity zones and large carbon isotope fluctuations in the Lopingian are recognized and provide the high-resolution calibration that is essential to study this Late Permian interval characterized by Earth's largest biotic extinction. We also present a global correlation chart for the marine Lopingian Series. Copyright © 2010 John Wiley & Sons, Ltd. [source]

    Lopingian (Late Permian) high-resolution conodont biostratigraphy in Iran with comparison to South China zonation

    GEOLOGICAL JOURNAL, Issue 2-3 2010
    Shu-Zhong Shen
    Abstract Lopingian (Late Permian) conodonts and stratigraphy in northwest and central Iran have become hotly debated issues recently. We here use a sample-population approach, to develop a high-resolution conodont biostratigraphic framework for the Lopingian of Iran based on a re-examination of collections studied by Sweet from the Kuh-e-Ali Bashi area, northwest Iran; samples from the Abadeh C section and a nearby Permian-Triassic boundary section in the Abadeh area; and on published data. Six Wuchiapingian conodont zones, the Clarkina dukouensis, C. asymmetrica, C. leveni, C. guangyuanensis, C. transcaucasica and C. orientalis zones, and eight Changhsingian conodont zones, the Clarkina wangi, C. subcarinata, C. changxingensis, C. bachmanni, C. nodosa, C. yini, C. abadehensis and C. hauschkei zones, are described and figured. Diagnoses of ontogenetic characteristics to population variations of all the zone-naming species are re-described based on a sample-population taxonomic concept. The high-resolution Lopingian conodont zonation in Iran is closely correlative with its counterpart in South China. However, slightly different evolutionary trends in Clarkina populations existed at the very end of the Changhsingian in Iran and South China. This reflects a geographical cline and/or facies dependence and endemism in Clarkina populations rather than stratigraphic incompleteness of sections in either Iran or South China. Copyright © 2010 John Wiley & Sons, Ltd. [source]

    The diversification and extinction of Doushantuo-Pertatataka acritarchs in South China: causes and biostratigraphic significance

    GEOLOGICAL JOURNAL, Issue 3-4 2007
    Zhou Chuanming
    Abstract The Ediacaran Period immediately follows the last Cryogenian glaciation,the ,635,Ma Marinoan or Nantuo glaciation, and it is also punctuated by another brief glaciation,the ,582,Ma Gaskiers glaciation. It is possible that these glaciations may have had significant impact on Ediacaran biological evolution (e.g. the appearance or disappearance of Doushantuo-Pertatataka acritarchs). Alternative hypotheses propose that the diversification of Doushantuo-Pertatataka acritarchs was caused by the Acraman bolide impact or by emerging eumetazoans. To test these hypotheses, high-resolution geochronological and biostratigraphic data are required. The Doushantuo Formation in South China, radiometrically constrained between ,635 and ,551,Ma, has the potential to clarify the global picture of early-middle Ediacaran evolution. Here we present preliminary biostratigraphic data from the Doushantuo Formation in the East Yangtze Gorges area and new ,13C chemostratigraphic data from the Doushantuo Formation at Weng'an. These and previously published palaeontological data, aided by the tool of ,13C chemostratigraphy, indicate that the biostratigraphic record of the Doushantuo Formation is locally sensitive to the availability of specific taphonomic windows. In the East Yangtze Gorges area, Doushantuo-Pertatataka acritarchs first appeared shortly after the termination of the Nantuo glaciation and gradually diversified throughout the Doushantuo Formation. At Weng'an, however, such acritarchs first appear,abruptly and in much greater diversity,in phosphorite of the upper Doushantuo Formation, immediately above a subaerial exposure surface. Thus, the biostratigraphic pattern in the East Yangtze Gorges area permits, whereas that at Weng'an apparently disallows, a causal relationship between the Nantuo glaciation and the diversification of Doushantuo-Pertatataka acritarchs. We conclude that the biostratigraphic record is incomplete at Weng'an, where the early Ediacaran evolutionary history is not preserved. The South China data indicate that special attention has to be paid to taphonomic and palaeoenvironmental analysis before extrapolating local and regional biostratigraphic ranges to make global interpretations. It is less clear when Doushantuo-Pertatataka acritarchs disappeared. Previous investigators have variously suggested that they disappeared before, at, or after, the Gaskiers glaciation. These hypotheses are difficult to test because of the lack of sedimentary evidence for the Gaskiers glaciation in South China and other regions (e.g. South Australia) where Doushantuo-Pertatataka acritarchs are abundant. In Australia, Doushantuo-Pertatataka acritarchs are thought to have experienced a sharp decline after the Egan glaciation, which may well be equivalent to the Gaskiers glaciation. If true, then Doushantuo-Pertatataka acritarchs are largely restricted to the interval between the Nantuo and Gaskiers glaciations. This conclusion allows us to place constraints on the possible causes of the diversification and extinction of Doushantuo-Pertatataka acritarchs and has important implications for the biostratigraphic significance of Doushantuo-Pertatataka acritarchs. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    ,-diversity fluctuations in Early,Mid Ordovician brachiopod communities of South China

    GEOLOGICAL JOURNAL, Issue 3-4 2006
    R.-B. Zhan
    Abstract Lower to Middle Ordovician transitional strata (Acrograptus filiformis Biozone to Exigraptus clavus Biozone) of the Upper Yangtze Platform contain rich and diverse brachiopods, particularly in the Daguanshan Formation of Sichuan Province, the Meitan Formation of Guizhou Province, and the Yingpan Formation of Houping, Chongqing City. On the basis of multivariate analyses of 207 samples (about 15,000 brachiopod specimens) and 61 species from these strata, 23 brachiopod-dominated communities and associations are delineated through six graptolitic biozones (Acrograptus filiformis to Exigraptus clavus biozones). The disparity of brachiopod associations or ,-diversity, as measured by the number of contemporaneous associations across variable ecological settings, was low in the A. filiformis Biozone and increased through the overlying graptolitic biozones to reach an acme in the Azygograptus suecisus and Expansograptus hirundo biozones, where as many as nine different brachiopod associations thrived in mid-shelf and also established in inner- and outer-shelf environments. Despite a sharp increase in ,-diversity within the Didymograptellus eobifidus Biozone, ,-diversity remained relatively low, with only three distinct brachiopod communities. The diversity of brachiopod associations suffered an abrupt drop in the E. clavus Biozone, as a result of a major faunal turnover event, with only a single Metorthis Community present in an upper mid-shelf setting. Temporally, brachiopod associations appear to be most stable in mid-shelf settings, with the Paralenorthis, Sinorthis, Desmorthis, and Euorthisina communities having a relatively high ,-diversity and lasting through two to five graptolitic biozones. In both species composition and temporal duration, the brachiopod associations at the shallow- (BA1 to upper BA2) and deep-shelf (BA4) settings are unstable, characterized by low ,-diversity and rapid vertical changes. This study implies that, during the Early and Mid Ordovician, brachiopod communities already attained a high level of organization in mid-shelf settings, but remained poorly established in high-stress environments of very shallow or very deep shelf settings. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    Ordovician graptolite evolutionary radiation: a review

    GEOLOGICAL JOURNAL, Issue 3-4 2006
    Chen Xu
    Abstract Based on the global graptolite genera and higher rank taxa, we propose three radiation stages through the Ordovician. The isograptid type of development is present within anisograptids predominating in the Tremadocian. Thus, the evolutionary radiation of the Anisograptid fauna from Tremadocian is proposed as the beginning of the Ordovician graptolite radiation. The second graptolite radiation event is the radiation of the Dichograptid fauna, which began from the T. fruticosus Biozone. The third radiation event, the radiation of Diplograptid fauna began immediately after that of the dichograptids. This radiation includes the peak in total diversity of all the Ordovician graptoloids in the Nemagraptus gracilis Biozone. The radiation extended through the Sandbian and Katian and then was interrupted by a major extinction during the early Hirnantian. Thus, the Ordovician graptolite radiation events coincide with those of the three graptolite faunas proposed by Bulman. The distribution and expansion of the Ordovician graptolites in South China may exemplify the graptolite origination pattern, which begins from the slope belt and expanded into both the shelf and oceanic zones. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    Distinctiveness of the cagA Genotype in Children and Adults with Peptic Symptoms in South China

    HELICOBACTER, Issue 4 2009
    Juan Li
    Abstract Background:,Helicobacter pylori infection is different between children and adults, not only in infection rate but also in virulence genotypes. However, the 3, region of CagA, important in stomach carcinogenesis, still remains unclear in children. The present study aims to compare the frequency of cagA and the distribution of its subtypes between children and adults in South China. Materials and Methods:, One hundred and twenty-eight children and 99 adults with peptic symptoms were enrolled in our research. Histology, rapid urease test, and real-time polymerase chain reaction (PCR) assay were used to diagnose H. pylori infection. vacA s1 was detected by real-time PCR, and EPIYA motifs in the 3, region of CagA by conventional PCR and DNA sequencing. Results:,H. pylori infection was diagnosed in 53 children and 62 adults. vacA s1 was identified in 90.6% and 91.9% of infected children and adults, respectively. Furthermore, cagA was identified in 73.6% and 82.3% of infected children and adults, respectively. No patient with multiple cagA subtypes was observed. A higher prevalence of more virulent cagA genotype was found in children compared to adults (p < .05). Thirty-eight of 39 (97.4%) cagA -positive children were found to have EPIYA-ABD and only one (2.6%) with EPIYA-ABC. In adults, four types of EPIYA motifs , ABC (29.4%), ABD (64.7%), ABAB (2%), and AAD (3.9%) , were identified, and the ABD type was found more commonly in severe diseases, such as atrophic gastritis (53.3%) and gastric cancer (71.4%). Conclusion:,cagA genotypes in children and in adults are different, and EPIYA-ABD may have potential clinical implication in the development of gastric cancer in South China. [source]

    Strategic HRM in China: Configurations and competitive advantage

    Irene H. Chow
    The strategic HR literature suggests that a firm will perform better through internal appropriate fit among HRM practices (the configuration fit) and through external appropriate fit between a firm's HRM practices and business strategy. The present study adopts a configuration approach to identify unique patterns of HR practices and business strategy that are posited to be maximally effective. The proposed relationships were empirically tested by surveying with a sample of 241 business firms in Guangzhou, South China, to find out the extent that four HR configurations could be successfully adopted in the Chinese context. The results revealed that HR configurations are significantly related to effect in predicting overall outcome performance and turnover, but not significantly related to effect on sales growth and profit growth rates. Research findings showed not only competitive strategies are significantly related to effect on HR configurations. The results also showed significant interaction effects between HR configurations and business strategy in their effect on profit and sales growth. These results further extended support for a contingency perspective in strategic HRM to the Chinese context, with significant practical implications for managing HRM in China. © 2008 Wiley Periodicals, Inc. [source]

    ApoG2, a novel inhibitor of antiapoptotic Bcl-2 family proteins, induces apoptosis and suppresses tumor growth in nasopharyngeal carcinoma xenografts

    Zhe-Yu Hu
    Abstract Nasopharyngeal carcinoma (NPC) is a common malignant tumor in South China. It has been reported that overexpression of antiapoptotic Bcl-2 family proteins in NPC has caused the lack of long-term efficacy of conventional therapies. Apogossypolone (ApoG2), a novel small-molecule inhibitor of antiapoptotic Bcl-2 family proteins, has been discovered as the optimized derivative of gossypol. In this study, we found that in NPC cells, ApoG2 totally blocked the antiapoptotic function of Bcl-2 family proteins without affecting the expression levels of these proteins. ApoG2 selectively inhibited proliferation of 3 NPC cell lines (C666-1, CNE-1 and CNE-2) that highly expressed the antiapoptotic Bcl-2 proteins. This inhibitory activity was associated with release of cytochrome c, activation of caspase-9 and caspase-3 and apoptosis of sensitive NPC cells. However, ApoG2 had no obvious inhibitory effect on NPC cell line HONE-1, which expressed antiapoptotic Bcl-2 and Bcl-xL at a low level. We further found that ApoG2 effectively suppressed tumor growth of NPC xenografts in nude mice and enhanced the antitumor effect of CDDP (cisplatin) on NPC cells in vitro and in vivo. Immunohistochemical results showed that the expression of CD31 decreased after ApoG2 treatment, which suggested inhibition of angiogenesis in NPC xenografts. Our findings strongly suggest that ApoG2 may serve as a novel inhibitor of Bcl-2 family proteins and, by targeting these proteins, may become a promising drug for the treatment of NPC. © 2008 Wiley-Liss, Inc. [source]

    Inter-decadal variation of the summer precipitation in East China and its association with decreasing Asian summer monsoon.

    Part I: Observed evidences
    Abstract In recent two decades, North and Northeast China have suffered from severe and persistent droughts while the Yangtze River basin and South China have undergone much more significant heavy rainfall/floods events. This long-term change in the summer precipitation and associated large-scale monsoon circulation features have been examined by using the new dataset of 740 surface stations for recent 54 years (1951,2004) and about 123-yr (1880,2002) records of precipitation in East China. The following new findings have been highlighted: (1) One dominating mode of the inter-decadal variability of the summer precipitation in China is the near-80-yr oscillation. Other modes of 12-yr and 30,40-yr oscillations also play an important role in affecting regional inter-decadal variability. (2) In recent 54 years, the spatial pattern of the inter-decadal variability of summer precipitation in China is mainly structured with two meridional modes: the dipole pattern and the positive-negative-positive ("+ , + " pattern). In this period, a regime transition of meridional precipitation mode from "+ , + " pattern to dipole pattern has been completed. In the process of southward movement of much precipitation zone, two abrupt climate changing points that occurred in 1978 and 1992, respectively, were identified. (3) Accompanying the afore-described precipitation changes, the East Asian summer monsoon have experienced significant weakening, with northward moisture transport and convergence by the East Asian summer monsoon greatly weakened, thus leading to much deficient moisture supply for precipitation in North China. (4) The significant weakening of the component of the tropical upper-level easterly jet (TEJ) has made a dominating contribution to the weakening of the Asian summer monsoon system. The cooling in the high troposphere at mid- and high latitudes and the possible warming at low latitude in the Asian region is likely to be responsible for the inter-decadal weakening of the TEJ. Copyright © 2007 Royal Meteorological Society [source]

    Ten-year climatology of summer monsoon over South China and its surroundings simulated from a regional climate model

    Yiming Liu
    Abstract In a previous study by the authors, a regional climate model (hereafter the RCM) developed to study the summer monsoon over South China (SC) and the South China Sea (SCS) has been tested and found to be able to simulate to a large extent the precipitation over this region for the months of May and June. To examine the interannual variability of the summer monsoon here, it is necessary to establish a model climatology to serve as a comparison and to reduce or even remove any systematic model biases. This paper presents the analyses of such a 10-year climatology (1991,2000). The model was initialized on 1 April and integrated up to the end of June for the ten years. The initial atmospheric conditions and lateral boundary data used in this study are from the European Centre for Medium-range Weather Forecasts ,40-year' reanalyses. The RCM can reproduce well the main features of the monsoon circulation and vertical structure of the atmosphere. The RCM can simulate the intensification and northwestward displacement of the south Asian upper anticyclones from May to June, as well as the low-level moisture transport from the Bay of Bengal to SC. In the simulation, the average SCS summer monsoon onset occurs in the fourth pentad of May, which is consistent with the results from previous observational research. In addition, the RCM can reproduce the main characteristics of the onset such as the change of the low-level zonal flow from easterly to westerly as well as the rapid increase in daily precipitation. The SC and SCS precipitation anomalies have the correct sign in almost all the years. The shortcomings of the model simulation include an under-prediction of the strength of the subtropical high over the Northwest Pacific and the moisture transport from the Bay of Bengal to the Indochina Peninsula (IC) and SCS. A cold bias in surface air temperature is also observed, with the 10-year mean biases of the simulated surface air temperature over SC, SCS and IC in May and June being about ,2.1 °C, ,2.4 °C and ,1.4 °C respectively. The 10-year mean biases of the simulated daily precipitation rate over SC, SCS and IC are about 2.0, ,3.8 and 3.5 mm d,1 respectively. Copyright © 2005 Royal Meteorological Society. [source]

    Zooplankton Distribution in Tropical Reservoirs, South China

    Qiu-Qi Lin
    Abstract The zooplankton of 18 reservoirs of South China was investigated in 2000. 61 Rotifera species, 23 Cladoceras and 14 Copepodas were identified. The most frequent Rotifera genera were Keratella, Brachionus, Trichocerca, Diurella, Ascomorpha, Polyarthra, Ploesoma, Asplanchna, Pompholyx and Conochilus. Bosmina longirostris, Bosminopsis deitersi, Diaphanosoma birgei, D. brachyurum and Moina micrura were typical of Cladocera in the reservoirs. Phyllodiaptomus tunguidus, Neodiaptomus schmackeri and Mesocyclops leuckarti were the most frequent Copepoda and M. leuckarti dominated Copepoda in most reservoirs. High zooplankton species richness with low abundance was characteristic of the throughflowing reservoir, whereas low species richness with low abundance was found in the reservoir with the longest retention time. Relative high abundance and medium species diversity were the distinction of intermediate retention time reservoirs. [source]

    Effects of Relationship Values and Goal Interdependence on Guanxi Between Foreign Managers and Chinese Employees,

    Nancy Chen Yi-Feng
    Foreign managers are advised to develop effective relationships with Chinese employees who as collectivists are thought to value relationships, particularly guanxi, with their leaders. However, foreign managers typically do not have the background and prior experiences typically used to develop guanxi in China. In an experiment with 120 participants in South China, Chinese employees with foreign managers who communicated that they wanted a relationship (compared to no relationship) with them concluded that they interacted better and had little relational and task conflict. Chinese employees who discussed their views within a cooperative (compared to competitive) context helped their leader, productively integrated their diverse views into the decision, and concluded that they had little relational and task conflict. [source]


    ABSTRACT Leaves of Adinandra nitida are consumed in southern China as health tea (Shiyacha) and as herbal medicine. In this study, the methanol and supercritical fluid extracts from leaves of A. nitida were obtained by traditional solvent extraction and supercritical carbon dioxide extraction, respectively. Both the extracts showed high 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. By using ultraviolet-visible spectrometry (UV), infrared spectrometry (IR), nuclear magnetic resonance, electrospray ionization mass spectrometry (ESI-MS), high-performance liquid chromatography-ESI/MS, the main bioactive constituents in the methanol extract (ME) were identified as camellianin A, camellianin B, apigenin. By analysis of gas chromatography-mass spectrometry, a total of 16 compounds accounting for 98.79% of the supercritical fluid extract (SFE) were identified as ,-sitosterol, vitamin E, ,-tocopherol and so on. These compounds found in ME and SFE could contribute to the DPPH radical scavenging performance of the extracts in this study. PRACTICAL APPLICATION Adinandra nitida is a kind of particular wild plant in South China. Few reports have been published about it in the world. In this study, the methanol and supercritical fluid extracts from leaves of A. nitida were respectively obtained by two kinds of industrially significant methods, traditional solvent extraction and supercritical carbon dioxide extraction. By using ultraviolet-visible spectrometry (UV), infrared spectrometry (IR), nuclear magnetic resonance, electrospray ionization mass spectrometry (ESI-MS), high-performance liquid chromatography-ESI/MS, gas chromatography-MS, the main bioactive constituents in the two extracts were identified as flavonoids and plant sterols. Both the extracts showed high 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and this activity of the flavonoid-rich methanol extract was 10 times more than that of butylated hydroxytoluene. These results showed that leaves of A. nitida is a new kind of natural antioxidant-rich, flavonoid-rich plant source with great commercial interest in the food and phytopharmaceutical market. [source]

    Seed Dynamics in Relation to Gaps in a Tropical Montane Rainforest of Hainan Island, South China: (II) Seed Bank

    Run-Guo Zang
    Abstract Spatial and temporal patterns of seed bank dynamics in relation to gaps in an old growth tropical montane rainforest of Hainan Island, South China, were studied over two consecutive years. From June 2001 to June 2003, soil seed bank sampling blocks were taken near each of the four sides of each seed trap and immediately put into a nursery for observation of seedling emergence dynamics in four seasons (each experiment in each season). The abundances of seedlings that emerged from seed banks showed the trend of vine functional group (VFG) > shrub functional group (SFG) > tree functional group (TFG) > herb functional group (HFG), but the trend in species richness of seedlings that emerged from the soil seed banks was TFG > VFG > SFG > HFG. The abundances of seedlings that emerged from seed banks in the three gap zones showed no significant differences, but significant differences did exist for the species richness. The time of sampling or seasons of experiments had significant influences on both the species richness and seedling abundances. The seedling emergence processes of each experiment all revealed the unimodal patterns. Few emergences occurred 1 year after each experiment. Compared with those under closed canopies, the recruitment rates from seed to seedlings and from seedlings to saplings in gaps were higher, but the mortality rates from saplings to big trees were also higher in the gaps. [source]

    Regulation of Light Energy Utilization and Distribution of Photosynthesis in Five Subtropical Woody Plants

    Nan Liu
    Abstract The adaptations and responses of photosynthesis to long- and short-term growth light gradient treatments were investigated in five subtropical forest plants, namely Pinus massoniana Lamb., Schima superba Gardn. et Champ., Castanopsis fissa (Champ. ex Benth.) Rehd. et Wils., Acmena acuminatissima (BI.) Merr et Perry, and Cryptocarya concinna Hance. With diurnal changes in sunlight and air temperature, the de-epoxidation state and lutein content in the five woody plants under three light intensities first increased and then decreased during the day. However, maximal photochemical efficiency (Fv/Fm; where Fm is the maximum fluorescence yield and Fv is variable fluorescence) and the photochemical quantum yields of photosystem (PS) II (,PSII) of the species examined changed in the opposite manner, with those in plants grown under 100% natural light changing the most. After long-term treatment (21 months), anti-oxidant capacity (1, 1-diphenyl-2-picrylhydrazyl radical (DPPH·)-scavenging capacity) and utilization of excitation energy showed differences in modulation by different light intensities. It was shown that A. acuminatissima and C. concinna, as dominant species in the late succession stage of a subtropical forest in Dinghu mountain, South China, were better able to adapt to different light environments. However, P. massoniana, the pioneer species of this forest, exhibited less adaptation to low light intensity and was definitely eliminated by the forest succession process. [source]

    Genetic Diversity of Cryphonectria hypovirus 1 in China, Japan and Italy

    F.-X. Liu
    Abstract The aim of this study was to examine the origin of Cryphonectria hypovirus 1 (CHV1) which infects chestnut blight fungus, Cryphonectria parasitica. The genetic diversity of 39 CHV1 isolates from China, Japan and Italy was assessed by combining sequencing and restriction fragment length polymorphic (RFLP) experiments. Based on their partial sequences, 26 CHV1 isolates within 26 haplotypes were grouped into three subtypes. The 17 viruses from China were distributed between subtypes I and III, while all four of the isolates from Japan were subtype II. Of the five isolates from Italy, four were subtype I, and one (IT 192) was subtype III. Our analysis of the geographic distribution of the isolates indicated that all but one of the Chinese subtype III CHV1s are present in northern China; meanwhile all but three of the Chinese subtype I CHV1s are present in South China. Unlike in Europe where there is one predominant CHV1 subtype, our distribution analysis indicates that there has been gene flow between the populations in Asia. Cluster analysis based on the RFLP banding patterns showed that the viral isolates could be separated into four clusters. Most of the viral isolates (29 of 39, 74.4%) were grouped into one large cluster. Greater genetic diversity was observed among the CHV1s from China than among those from Japan and Italy. The Italian isolates were genetically more similar to the Japanese and South Chinese isolates than to the North Chinese isolates, indicating that CHV1 in Italy may have originated from Japan and/or South China. [source]

    A gregarious lingulid brachiopod Longtancunella chengjiangensis from the Lower Cambrian, South China

    LETHAIA, Issue 1 2007
    Longtancunella chengjiangensis, one of the sparse lingulid brachiopods from the Early Cambrian Chengjiang Lagerstätten of southwestern China, is characterized by a sub-circular shell shape, stout pedicle, and notably by gregarious occurrences in the fossils. This brachiopod form was briefly reported in 1999, but its detailed description, however, remains to be done. The material in our collection is remarkably well preserved and allows accounts of the shell morphology and of valve interiors, including lophophores, mantle canals, and a digestive tract. When compared with the coeval lingulid brachiopod Xianshanella haikouensis Zhang & Han, 2004, L. chengjiangensis exhibits some distinct features, notably tenuous marginal setae and distinguishable mantle canals and a relative short pedicle tapering posteriorly. [source]

    Biotic diachroneity during the Ordovician Radiation: evidence from South China

    LETHAIA, Issue 3 2006
    Renbin Zhan
    The Ordovician radiation was one of the most marked and sustained increases in Phanerozoic biodiversification; nevertheless it occurred against a background of minimal global climatic and environmental perturbations. Detailed investigations of the Ordovician successions on the Yangtze Platform of the South China palaeoplate indicate that: (1) the brachiopod ,- and ,-diversity changes are diachronous; (2) macroevolutionary patterns were different across the South China palaeoplate, with the Early Ordovician brachiopod radiation first occurring in normal marine, shallow-water environments and then moving gradually to both nearer-shore and offshore locations; (3) the main contributors to the initial Ordovician brachiopod radiation were the Orthida and Pentamerida; the typical Ordovician brachiopod fauna, dominated by the Orthida and Strophomenida, did not appear until the late Mid Ordovician (Undulograptus austrodentatus Biozone) when the Strophomenida apparently replaced the dominant position of the Pentamerida within the fauna; (4) different ecotypes (e.g., sessile benthos, mobile benthos together with pelagic and planktonic organisms) demonstrate substantially different macroevolutionary patterns. The Ordovician brachiopod radiation of South China was apparently earlier than that suggested by global trends together with the data available from other palaeoplates or terranes, which may be related to its unique palaeogeographic position (peri-Gondwanan terrane gradually moving to equatorial latitudes). [source]

    Surviving the end-Ordovician extinctions: evidence from the earliest Silurian brachiopods of northeastern Jiangxi and western Zhejiang provinces, East China

    LETHAIA, Issue 1 2006
    Earliest Rhuddanian (Silurian) brachiopods are recorded from the basal part of the Lower Llandovery Shiyang and Anji formations in western Zhejiang and northeastern Jiangxi provinces, East China. Associated graptolites including Normalograptus jerini indicate the lowest Rhuddanian Akidograptus ascensus Biozone. The surviving brachiopod fauna includes 19 genera dominated by orthids and strophomenids, whereas pentamerids and atrypids that inhabited mainly warmer water regimes, and were almost absent in the cool/cold Hirnantia Fauna, occur rarely in the studied fauna. Each family is represented by a single genus that seeded their recovery. The predominance of these long-ranging and widely distributed genera is one of major characters of the brachiopod survival in east China. From qualitative and quantitative analysis of faunal composition, diversity and abundance, with evidences from palaeoecology and palaeogeography, the Levenea qianbeiensis Association, Katastrophomena-Leptaena-Levenea Association, and Glyptorthis-Epitomyonia-Levenea Association are recognized and assigned to BA (Benthic Assemblage) 2, BA3, and an ecozone close to the BA3-4 boundary respectively. No Lazarus genera are recorded in this study. Skenidioides and Epitomyonia were chiefly regarded as deeper-water taxa in the Ordovician and Silurian, but are recorded from shallow-water in east China during the early Rhuddanian, indicating an ecologic experiment with these taxa migrating from deep into shallower, better-oxygenated sites at the crisis time and during the subsequent survival interval. This study further demonstrates that the brachiopod faunal turnover after the end-Ordovician extinctions may not have been completed until the late Rhuddanian in South China. [source]

    Diversity and extinction patterns of Permian coral faunas of China

    LETHAIA, Issue 4 2000
    Xiang-Dong Wang
    Coral diversity and extinction patterns in the Permian of China are revealed through statistical analyses of 56 coral families, 263 genera and 2100 species from five consecutive time intervals. The highest coral diversity is in the Chuanshanian, with 753 species, 167 genera and 39 families. In contrast, the lowest diversity is in the Changhsingian, with only 68 species, 20 genera and 10 families. Two decreases in diversity can be recognized during the Permian. The first occurred at the end of the Maokouan (end-Guadalupian) and is marked by the loss of 75.6% of coral families, 77.8% of coral genera and 82.2% of coral species. The second major diversity drop took place at the end of the Changhsingian, when all rugose and tabulate corals became extinct. The extinction at the end of the Guadalupian in Pangea may be related to the middle Permian global regression. However, in South China the end-Maokouan extinction may be related to the eruption of the Omeishan Basalt. A triple-zoned palaeobiogeographical pattern is well expressed by coral diversity. [source]

    A population-based epidemiologic study of irritable bowel syndrome in South China: stratified randomized study by cluster sampling

    L. S. Xiong
    Summary Background :,The detailed population-based data on irritable bowel syndrome in South China are lacking. Aims :,To assess the prevalence of irritable bowel syndrome in South China and its impact on health-related quality of life. Subjects and methods :,A face-to-face interview was carried out in South China to assess the prevalence of irritable bowel syndrome. Random clustered sampling of permanent inhabitants aged 18,80 years was carried out under stratification of urban and suburban areas. The impact of irritable bowel syndrome on health-related quality of life was evaluated using the Chinese version of SF-36. Results :,A total of 4178 subjects (1907 male and 2271 female) were interviewed. The adjusted prevalence of irritable bowel syndrome in South China is 11.50% according to the Manning criteria and 5.67% according to the Rome II criteria. Factors including history of analgesic use such as non-steroidal anti-inflammatory drug (odds ratio 3.83), history of food allergies (odds ratio 2.68), psychological distress (odds ratio 2.18), life events (odds ratio 1.89), history of dysentery (odds ratio 1.63) and negative coping style (odds ratio 1.28) were significantly associated with the presence of irritable bowel syndrome (P < 0.05). Irritable bowel syndrome was significantly associated with a decrement in health-related quality of life score. Conclusion :,Irritable bowel syndrome is a common disorder in South China and has a negative impact on health-related quality of life. [source]

    Grounding displacement: Uncivil urban spaces in postreform South China

    This historical,ethnographic study of village enclaves in Guangzhou explores the intensified entrenchment of villagers in a Maoist past when they faced market fluidities of a postreform present. It underscores a rural,urban spatiality and a cultural divide between villagers, migrants, and urbanites that are simultaneously transgressed and reinforced. It highlights discursive categories and institutional practices that incarcerate the residents, who juggle lingering socialist parameters with compelling market forces and state development priorities. Connectivity and exclusion, agency and victimization, groundedness and dislocation as lived experience are captured by the historically thick social ethos in the enclaves. This article rethinks issues of emplacement and displacement, dichotomy, and process. [source]


    PALAEONTOLOGY, Issue 2 2009
    Abstract:, Based on new, bed-rock controlled material from Oman and Utah, USA, the Early Triassic genus Guodunites, which was recently erected on the basis of scarce specimens from northwestern Guangxi, South China, is now shown to be a representative of Proptychitidae. This solves the question of the previously unknown phylogenetic affinity of this genus. The genus is restricted to the late middle Smithian, and to date, its biogeographical distribution comprises Oman, South China and Utah, thus indicating an essentially low palaeolatitudinal distribution during the Early Triassic. Its palaeobiogeographical distribution further strengthens the existence of significant equatorial faunal exchanges between both sides of the Panthalassa at that time. It also suggests that, in addition to the potential stepping stones represented by Panthalassic terranes, vigorous equatorial oceanic currents must have contributed largely to the dispersal of ammonoids during such time intervals. [source]


    PALAEONTOLOGY, Issue 1 2009
    Abstract:, The eastern Alborz Mountains of Iran comprise a significant peri-Gondwanan terrane relevant to the early evolution of late Cambrian , early Ordovician brachiopods incorporated into the emerging benthic biota of the Paleozoic Evolutionary Fauna. A low diversity brachiopod assemblage from the late Tremadocian unit of the Lashkarak Formation contains six new species including the polytoechioideans Polytoechia and Protambonites and the orthoideans Paralenorthis, Ranorthis, Tarfaya and Xianorthis. The fauna preserves the earliest records of Polytoechia, unknown previously outside Laurentia and the Uralian margin of Baltica, and of Paralenorthis and Ranorthis, which were widespread along Gondwanan margins and in Baltica from the Floian (Arenig), plus Xianorthis, known hitherto only from the Floian of South China. The enigmatic Tarfaya has an impunctate shell fabric and setigerous perforations along the posterior margin, indicating placement within the Orthoidea in a new Family Tarfayidae. New species of Polytoechia, Protambonites, Paralenorthis, Ranorthis, Tarfaya, Xianorthis are described. [source]


    PALAEONTOLOGY, Issue 2 2007
    Abstract:, Twenty-nine Arenig and Llanvirn trilobite species, representing 20 genera in the Asaphidae, Cyclopygidae, Dikelokephalinidae, Nileidae, Raphiophoridae, Remopleurididae, Taihungshaniidae and Trinucleidae, are treated in a taxonomic review of the South Chinese Asaphida. This review is based on large collections of trilobite material made from five formations at nine localities in western Hubei, northern Hunan and southern Shaanxi, representing a wide range of benthic marine environments across the Yangtze Platform and Jiangnan Transitional Belt regions of the South China Plate. Most South Chinese representatives of the Asaphidae are reassigned to the Nobiliasaphinae on the basis of cranidial and hypostomal characters, and taxonomic revisions are given for Liomegalaspides and Opsimasaphus pseudodawanicus. Taihungshania shui and T. tachengssuensis are revised and redescribed, and the establishment of lectotypes for these species and T. brevica clarifies the status of the type material of Taihungshania. Nileus walcotti is revised and restricted biogeographically to the South China Plate; material from Xinjiang previously assigned to this species is reassigned to N. sericeus sp. nov. The new raphiophorid species Raphioampyx sinankylosus is described. Aocaspis, Incaia and Raphioampyx are recorded for the first time from South China, and the latter two genera are also recorded for the first time from the Arenig. [source]


    PALAEONTOLOGY, Issue 3 2006
    Abstract:, The ontogeny of Pseudopetigurus deprati Turvey et al., 2006 from the Ordovician Dawan Formation (Arenigian), Anhui Province, South China, is described. The presence of an anterior cranidial border in Pseudopetigurus is recognized for the first time. On account of the short (tr.), spindle-shaped anterior border, and the distinct, steeply inclined, wall-like pygidial margin, Pseudopetigurus is assigned to the family Dimeropygidae, the first genus of this family endemic to Gondwana. It has previously been regarded as a member of family Isocolidae. Cladistic analysis of species assigned to Dimeropygidae supports the monophyly of a clade including Dimeropyge, Dimeropygiella, Ischyrotoma, Pseudohystricurus and Pseudopetigurus, which may represent a subfamily Dimeropyginae. The distribution of Dimeropyginae shows a predominantly palaeotropical distribution, while the Gondwana Pseudopetigurus must have diverged from the dimeropygine common ancestor in pre-Arenigian time. [source]


    PALAEONTOLOGY, Issue 2 2006
    Abstract:, Brachiopods from the late Ordovician (late Caradoc) Dulankara Formation of the Chu-Ili Range, Kazakhstan, are reviewed. Those from the upper two members of the formation, the Degeres and Akkol members, are systematically described. New genera from the Dulankara Formation are Nikitinamena (Plectambonitoidea: Leptellinidae), with type species Nikitinamena bicostata sp. nov., and Weberorthis (Orthoidea: Plectorthidae), with type species Mimella brevis Rukavishnikova. Another new genus is Glyptomenoides (Strophomenoidea: Glyptomenidae), with type species Rafinesquina girvanensis Salmon from the Caradoc of Girvan, Scotland. Other new species from the Dulankara Formation are Holtedahlina orientalis, Platymena tersa, Christiania proclivis, Leangella (Leangella) paletsae, Metambonites subcarinatus, Ogmoplecia nesca and Plectorthis licta. The ecology and assemblages of all three members of the Dulankara Formation are identified or reviewed, and their palaeogeographical significance assessed: the Chu-Ili Terrane (on which the Dulankara Formation was situated during the Ordovician) formed part of the relatively low-latitude peri-Gondwanan complex of terranes, and was probably not far from North and South China. The faunal links suggested between the Dulankara brachiopods and contemporary faunas from Australia are now perceived to be weaker than previously thought. [source]