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Showing papers by "Chinese Academy of Sciences published in 2003"


Journal ArticleDOI
John W. Belmont1, Paul Hardenbol, Thomas D. Willis, Fuli Yu1, Huanming Yang2, Lan Yang Ch'Ang, Wei Huang3, Bin Liu2, Yan Shen3, Paul K.H. Tam4, Lap-Chee Tsui4, Mary M.Y. Waye5, Jeffrey Tze Fei Wong6, Changqing Zeng2, Qingrun Zhang2, Mark S. Chee7, Luana Galver7, Semyon Kruglyak7, Sarah S. Murray7, Arnold Oliphant7, Alexandre Montpetit8, Fanny Chagnon8, Vincent Ferretti8, Martin Leboeuf8, Michael S. Phillips8, Andrei Verner8, Shenghui Duan9, Denise L. Lind10, Raymond D. Miller9, John P. Rice9, Nancy L. Saccone9, Patricia Taillon-Miller9, Ming Xiao10, Akihiro Sekine, Koki Sorimachi, Yoichi Tanaka, Tatsuhiko Tsunoda, Eiji Yoshino, David R. Bentley11, Sarah E. Hunt11, Don Powell11, Houcan Zhang12, Ichiro Matsuda13, Yoshimitsu Fukushima14, Darryl Macer15, Eiko Suda15, Charles N. Rotimi16, Clement Adebamowo17, Toyin Aniagwu17, Patricia A. Marshall18, Olayemi Matthew17, Chibuzor Nkwodimmah17, Charmaine D.M. Royal16, Mark Leppert19, Missy Dixon19, Fiona Cunningham20, Ardavan Kanani20, Gudmundur A. Thorisson20, Peter E. Chen21, David J. Cutler21, Carl S. Kashuk21, Peter Donnelly22, Jonathan Marchini22, Gilean McVean22, Simon Myers22, Lon R. Cardon22, Andrew P. Morris22, Bruce S. Weir23, James C. Mullikin24, Michael Feolo24, Mark J. Daly25, Renzong Qiu26, Alastair Kent, Georgia M. Dunston16, Kazuto Kato27, Norio Niikawa28, Jessica Watkin29, Richard A. Gibbs1, Erica Sodergren1, George M. Weinstock1, Richard K. Wilson9, Lucinda Fulton9, Jane Rogers11, Bruce W. Birren25, Hua Han2, Hongguang Wang, Martin Godbout30, John C. Wallenburg8, Paul L'Archevêque, Guy Bellemare, Kazuo Todani, Takashi Fujita, Satoshi Tanaka, Arthur L. Holden, Francis S. Collins24, Lisa D. Brooks24, Jean E. McEwen24, Mark S. Guyer24, Elke Jordan31, Jane Peterson24, Jack Spiegel24, Lawrence M. Sung32, Lynn F. Zacharia24, Karen Kennedy29, Michael Dunn29, Richard Seabrook29, Mark Shillito, Barbara Skene29, John Stewart29, David Valle21, Ellen Wright Clayton33, Lynn B. Jorde19, Aravinda Chakravarti21, Mildred K. Cho34, Troy Duster35, Troy Duster36, Morris W. Foster37, Maria Jasperse38, Bartha Maria Knoppers39, Pui-Yan Kwok10, Julio Licinio40, Jeffrey C. Long41, Pilar N. Ossorio42, Vivian Ota Wang33, Charles N. Rotimi16, Patricia Spallone29, Patricia Spallone43, Sharon F. Terry44, Eric S. Lander25, Eric H. Lai45, Deborah A. Nickerson46, Gonçalo R. Abecasis41, David Altshuler47, Michael Boehnke41, Panos Deloukas11, Julie A. Douglas41, Stacey Gabriel25, Richard R. Hudson48, Thomas J. Hudson8, Leonid Kruglyak49, Yusuke Nakamura50, Robert L. Nussbaum24, Stephen F. Schaffner25, Stephen T. Sherry24, Lincoln Stein20, Toshihiro Tanaka 
18 Dec 2003-Nature
TL;DR: The HapMap will allow the discovery of sequence variants that affect common disease, will facilitate development of diagnostic tools, and will enhance the ability to choose targets for therapeutic intervention.
Abstract: The goal of the International HapMap Project is to determine the common patterns of DNA sequence variation in the human genome and to make this information freely available in the public domain. An international consortium is developing a map of these patterns across the genome by determining the genotypes of one million or more sequence variants, their frequencies and the degree of association between them, in DNA samples from populations with ancestry from parts of Africa, Asia and Europe. The HapMap will allow the discovery of sequence variants that affect common disease, will facilitate development of diagnostic tools, and will enhance our ability to choose targets for therapeutic intervention.

5,926 citations


Journal ArticleDOI
TL;DR: In this paper, the authors report new field data for the Ondor Sum melange in the Ulan valley, and present a new evaluation of the orogenic belt extending from the southern Mongolia cratonic boundary to the north China craton.
Abstract: [1] The Solonker suture records the termination of the central Asian Orogenic Belt (CAOB). However, tectonic development of the Solonker suture is poorly understood. We report new field data for the Ondor Sum melange in the Ulan valley, and present a new evaluation of the orogenic belt extending from the southern Mongolia cratonic boundary to the north China craton within the context of a new geological framework and tectonic model, which incorporates relevant data from the literature. The southern accretionary zone between the north China craton and the Solonker suture is characterized by the Mid-Ordovician-Early Silurian Ulan island arc-Ondor Sum subduction-accretion complex and the Bainaimiao arc. This zone was consolidated by the Carboniferous-Permian when it evolved into an Andean-type magmatic margin above a south dipping subduction zone. The northern accretionary zone north of the Solonker suture extends southward from a Devonian to Carboniferous active continental margin, through the Hegenshan ophiolite-arc accretionary complex to the Late Carboniferous Baolidao arc associated with some accreted Precambrian blocks. This northern zone had consolidated by the Permian when it developed into an Andean-type magmatic margin above a north dipping subduction zone. Final subduction of the central Asian ocean caused the two opposing active continental margins to collide, leading to formation of the Solonker suture in the end-Permian. Predominant northward subduction during final formation of the suture gave rise in the upper northern plate to a large-scale, postcollisional, south directed thrust and fold belt in the Triassic-Jurassic. In summary, the CAOB underwent three final stages of tectonic development: early Japanese-type accretion, Andean-type magmatism, and Himalayan-type collision.

1,596 citations


Journal ArticleDOI
TL;DR: In this paper, a thermodynamic model for the solubility of carbon dioxide (CO 2 ) in pure water and in aqueous NaCl solutions for temperatures from 273 to 533 K, for pressures from 0 to 2000 bar, and for ionic strength from 0.3 m is presented.

1,442 citations


Journal ArticleDOI
TL;DR: A simple but efficient gait recognition algorithm using spatial-temporal silhouette analysis is proposed that implicitly captures the structural and transitional characteristics of gait.
Abstract: Human identification at a distance has recently gained growing interest from computer vision researchers. Gait recognition aims essentially to address this problem by identifying people based on the way they walk. In this paper, a simple but efficient gait recognition algorithm using spatial-temporal silhouette analysis is proposed. For each image sequence, a background subtraction algorithm and a simple correspondence procedure are first used to segment and track the moving silhouettes of a walking figure. Then, eigenspace transformation based on principal component analysis (PCA) is applied to time-varying distance signals derived from a sequence of silhouette images to reduce the dimensionality of the input feature space. Supervised pattern classification techniques are finally performed in the lower-dimensional eigenspace for recognition. This method implicitly captures the structural and transitional characteristics of gait. Extensive experimental results on outdoor image sequences demonstrate that the proposed algorithm has an encouraging recognition performance with relatively low computational cost.

1,183 citations


Journal ArticleDOI
TL;DR: Periodic nanostructures are observed inside silica glass after irradiation by a focused beam of a femtosecond Ti:sapphire laser, resulting in the periodic modulation of electron plasma concentration and the structural changes in glass.
Abstract: Periodic nanostructures are observed inside silica glass after irradiation by a focused beam of a femtosecond Ti:sapphire laser Backscattering electron images of the irradiated spot reveal a periodic structure of stripelike regions of ~20 nm width with a low oxygen concentration, which are aligned perpendicular to the laser polarization direction These are the smallest embedded structures ever created by light The period of self-organized grating structures can be controlled from ~140 to 320 nm by the pulse energy and the number of irradiated pulses The phenomenon is interpreted in terms of interference between the incident light field and the electric field of the bulk electron plasma wave, resulting in the periodic modulation of electron plasma concentration and the structural changes in glass

1,115 citations


Journal ArticleDOI
TL;DR: This paper provides a comprehensive survey of research on computer-vision-based human motion analysis, namely human detection, tracking and activity understanding, and various methods for each issue are discussed in order to examine the state of the art.

1,106 citations


Journal ArticleDOI
TL;DR: A bank of spatial filters, whose kernels are suitable for iris recognition, is used to capture local characteristics of the iris so as to produce discriminating texture features and results show that the proposed method has an encouraging performance.
Abstract: With an increasing emphasis on security, automated personal identification based on biometrics has been receiving extensive attention over the past decade. Iris recognition, as an emerging biometric recognition approach, is becoming a very active topic in both research and practical applications. In general, a typical iris recognition system includes iris imaging, iris liveness detection, and recognition. This paper focuses on the last issue and describes a new scheme for iris recognition from an image sequence. We first assess the quality of each image in the input sequence and select a clear iris image from such a sequence for subsequent recognition. A bank of spatial filters, whose kernels are suitable for iris recognition, is then used to capture local characteristics of the iris so as to produce discriminating texture features. Experimental results show that the proposed method has an encouraging performance. In particular, a comparative study of existing methods for iris recognition is conducted on an iris image database including 2,255 sequences from 213 subjects. Conclusions based on such a comparison using a nonparametric statistical method (the bootstrap) provide useful information for further research.

1,052 citations


Journal ArticleDOI
10 Apr 2003-Nature
TL;DR: The isolation and characterization of MONOCULM 1 (MOC1), a gene that is important in the control of rice tillering, is reported, which encodes a putative GRAS family nuclear protein that is expressed mainly in the axillary bud and functions to initiate axillary buds and to promote their outgrowth.
Abstract: Tillering in rice (Oryza sativa L.) is an important agronomic trait for grain production, and also a model system for the study of branching in monocotyledonous plants. Rice tiller is a specialized grain-bearing branch that is formed on the unelongated basal internode and grows independently of the mother stem (culm) by means of its own adventitious roots. Rice tillering occurs in a two-stage process: the formation of an axillary bud at each leaf axil and its subsequent outgrowth. Although the morphology and histology and some mutants of rice tillering have been well described, the molecular mechanism of rice tillering remains to be elucidated. Here we report the isolation and characterization of MONOCULM 1 (MOC1), a gene that is important in the control of rice tillering. The moc1 mutant plants have only a main culm without any tillers owing to a defect in the formation of tiller buds. MOC1 encodes a putative GRAS family nuclear protein that is expressed mainly in the axillary buds and functions to initiate axillary buds and to promote their outgrowth.

951 citations


Journal ArticleDOI
08 May 2003-Nature
TL;DR: It is shown that increasing force first prolonged and then shortened the lifetimes of P-selectin complexes with P- selectin glycoprotein ligand-1, revealing both catch and slip bond behaviour.
Abstract: Bonds between adhesion molecules are often mechanically stressed. A striking example is the tensile force applied to selectin-ligand bonds, which mediate the tethering and rolling of flowing leukocytes on vascular surfaces(1-3). It has been suggested that

949 citations


Journal ArticleDOI
01 Nov 2003-Geology
TL;DR: In this paper, the authors reported the first example of such magmas from southern Tibet in an active continental collision environment, and their overall geochemical characteristics suggest an origin by melting of eclogites and/or garnet amphibolites in the lower part of thickened Tibetan crust.
Abstract: Adakites are geochemically distinct intermediate to felsic lavas found exclusively in subduction zones. Here we report the first example of such magmas from southern Tibet in an active continental collision environment. The Tibetan adakites were emplaced from ca. 26 to 10 Ma, and their overall geochemical characteristics suggest an origin by melting of eclogites and/or garnet amphibolites in the lower part (≥50 km) of thickened Tibetan crust. This lower-crustal melting required a significantly elevated geotherm, which we attribute to removal of the tectonically thickened lithospheric mantle in late Oligocene time. The identification of collision-type adakites from southern Tibet lends new constraints to not only the Himalayan-Tibetan orogenesis—how and when the Indian lithosphere started underthrusting Asia can be depicted—but also the growth of the early continental crust on Earth that consists dominantly of the tonalite-trondhjemite-granodiorite suites marked by adakitic geochemical affinities.

922 citations


Journal ArticleDOI
10 Jan 2003-Science
TL;DR: Functional analysis of the S140G mutant revealed a gain-of-function effect on the KCNQ1/KCNE1 and theKCNQ 1/ KCNE2 currents, which contrasts with the dominant negative or loss-of -function effects of the KCnQ1 mutations previously identified in patients with long QT syndrome.
Abstract: Atrial fibrillation (AF) is a common cardiac arrhythmia whose molecular etiology is poorly understood. We studied a family with hereditary persistent AF and identified the causative mutation (S140G) in the KCNQ1 (KvLQT1) gene on chromosome 11p15.5. The KCNQ1 gene encodes the pore-forming alpha subunit of the cardiac I(Ks) channel (KCNQ1/KCNE1), the KCNQ1/KCNE2 and the KCNQ1/KCNE3 potassium channels. Functional analysis of the S140G mutant revealed a gain-of-function effect on the KCNQ1/KCNE1 and the KCNQ1/KCNE2 currents, which contrasts with the dominant negative or loss-of-function effects of the KCNQ1 mutations previously identified in patients with long QT syndrome. Thus, the S140G mutation is likely to initiate and maintain AF by reducing action potential duration and effective refractory period in atrial myocytes.

Journal ArticleDOI
TL;DR: This series of crystal structures, which is the first, to the authors' knowledge, of any protein from the SARS virus, reveal substantial pH-dependent conformational changes, and an unexpected mode of inhibitor binding, providing a structural basis for rational drug design.
Abstract: A newly identified severe acute respiratory syndrome coronavirus (SARS-CoV), is the etiological agent responsible for the outbreak of SARS. The SARS-CoV main protease, which is a 33.8-kDa protease (also called the 3C-like protease), plays a pivotal role in mediating viral replication and transcription functions through extensive proteolytic processing of two replicase polyproteins, pp1a (486 kDa) and pp1ab (790 kDa). Here, we report the crystal structures of the SARS-CoV main protease at different pH values and in complex with a specific inhibitor. The protease structure has a fold that can be described as an augmented serine-protease, but with a Cys-His at the active site. This series of crystal structures, which is the first, to our knowledge, of any protein from the SARS virus, reveal substantial pH-dependent conformational changes, and an unexpected mode of inhibitor binding, providing a structural basis for rational drug design.

Journal ArticleDOI
TL;DR: The International Global Atmospheric Chemistry Program (IGAC) has conducted a series of Aerosol Characterization Experiments (ACE) that integrate in situ measurements, satellite observations, and models to reduce the uncertainty in calculations of the climate forcing due to aerosol particles as discussed by the authors.
Abstract: [1] The International Global Atmospheric Chemistry Program (IGAC) has conducted a series of Aerosol Characterization Experiments (ACE) that integrate in situ measurements, satellite observations, and models to reduce the uncertainty in calculations of the climate forcing due to aerosol particles. ACE-Asia, the fourth in this series of experiments, consisted of two focused components: (1) An intensive field study that sought to quantify the spatial and vertical distribution of aerosol concentrations and properties, the processes controlling their formation, evolution, and fate, and the column-integrated radiative effect of the aerosol (late March through May 2001). (2) A longer-term network of ground stations that used in situ and column-integrated measurements to quantify the chemical, physical, and optical properties of aerosols in the ACE-Asia study area and to assess their spatial and temporal (seasonal and interannual) variability (2000–2003). The approach of the ACE-Asia science team was to make simultaneous measurements of aerosol chemical, physical, and optical properties and their radiative impacts in a variety of air masses, often coordinated with satellite overpasses. Three aircraft, two research ships, a network of lidars, and many surface sites gathered data on Asian aerosols. Chemical transport models (CTMs) were integrated into the program from the start, being used in a forecast mode during the intensive observation period to identify promising areas for airborne and ship observations and then later as tools for integrating observations. The testing and improvement of a wide range of aerosol models (including microphysical, radiative transfer, CTM, and global climate models) was one important way in which we assessed our understanding of the properties and controlling processes of Asian aerosols. We describe here the scientific goals and objectives of the ACE-Asia experiment, its observational strategies, the types of observations made by the mobile platforms and stationary sites, the models that will integrate our understanding of the climatic effect of aerosol particles, and the types of data that have been generated. Eight scientific questions focus the discussion. The intensive observations took place during a season of unusually heavy dust, so we have a large suite of observations of dust and its interaction with air pollutants. Further information about ACE-Asia can be found on the project Web site at http://saga.pmel.noaa.gov/aceasia/.

Journal ArticleDOI
01 Jan 2003-Carbon
TL;DR: In this paper, the individual and competitive adsorption capacities of Pb 2+, Cu 2+ and Cd 2+ by nitric acid treated multiwalled carbon nanotubes (CNTs) were studied.

Journal ArticleDOI
TL;DR: A semiempirical method for the evaluation of hardness of multicomponent crystals is presented and it is found that bond density or electronic density, bond length, and degree of covalent bonding are three determinative factors for the hardness of a polar covalents crystal.
Abstract: Based on the idea that the hardness of covalent crystal is intrinsic and equivalent to the sum of the resistance to the indenter of each bond per unit area, a semiempirical method for the evaluation of hardness of multicomponent crystals is presented. Applied to beta-BC2N crystal, the predicted value of hardness is in good agreement with the experimental value. It is found that bond density or electronic density, bond length, and degree of covalent bonding are three determinative factors for the hardness of a polar covalent crystal. Our method offers the advantage of applicability to a broad class of materials and initializes a link between macroscopic property and electronic structure from first principles calculation.

Journal ArticleDOI
TL;DR: It was shown that the drugs were capsulated inside of the fibers and the drug release in the presence of proteinase K followed nearly zero-order kinetics due to the degradation of the PLLA fibers.

Journal ArticleDOI
03 Oct 2003-Science
TL;DR: It is shown that the magnetic monopole can appear in the crystal momentum space of solids in the accessible low-energy region in the context of the anomalous Hall effect.
Abstract: Efforts to find the magnetic monopole in real space have been made in cosmic rays and in particle accelerators, but there has not yet been any firm evidence for its existence because of its very heavy mass, ∼10 16 giga–electron volts We show that the magnetic monopole can appear in the crystal momentum space of solids in the accessible low-energy region (∼01 to 1 electron volts) in the context of the anomalous Hall effect We report experimental results together with first-principles calculations on the ferromagnetic crystal SrRuO 3 that provide evidence for the magnetic monopole in the crystal momentum space

Journal ArticleDOI
TL;DR: It has been concluded that the surfactant containing a single straight-chain hydrophobic segment and a terminal hydrophilic segment can modify the CNTs-suspending medium interface and prevent aggregation over long periods.

Journal ArticleDOI
TL;DR: A spectral method derived from graph theory was introduced to uncover hidden topological structures (i.e. quasi-cliques and quasi-bipartites) of complicated protein-protein interaction networks and suggest that they consist of biologically relevant functional groups.
Abstract: Interaction detection methods have led to the discovery of thousands of interactions between proteins, and discerning relevance within large-scale data sets is important to present-day biology. Here, a spectral method derived from graph theory was introduced to uncover hidden topological structures (i.e. quasi-cliques and quasi-bipartites) of complicated protein-protein interaction networks. Our analyses suggest that these hidden topological structures consist of biologically relevant functional groups. This result motivates a new method to predict the function of uncharacterized proteins based on the classification of known proteins within topological structures. Using this spectral analysis method, 48 quasi-cliques and six quasi-bipartites were isolated from a network involving 11,855 interactions among 2617 proteins in budding yeast, and 76 uncharacterized proteins were assigned functions.

Journal ArticleDOI
01 Jan 2003-Carbon
TL;DR: In this article, carbon nanotubes (CNTs) were oxidized with H2O2, KMnO4, and HNO3, and the experimental results suggest that cadmium(II) adsorption capacities for three kinds of oxidized CNTs increase due to the functional groups introduced by oxidation compared with the as-grown CNT.

Journal ArticleDOI
TL;DR: It is shown that although challenges still exist, the above‐mentioned obstacles are now being removed, and recent advances in technology and increases in statistical power provide the prospect of nuclear DNA analyses becoming routine practice, allowing allele‐discriminating characterization of scnp loci and microsatellite loci.
Abstract: Population-genetic studies have been remarkably productive and successful in the last decade following the invention of PCR technology and the introduction of mitochondrial and microsatellite DNA markers. While mitochondrial DNA has proven powerful for genealogical and evolutionary studies of animal populations, and microsatellite sequences are the most revealing DNA markers available so far for inferring population structure and dynamics, they both have important and unavoidable limitations. To obtain a fuller picture of the history and evolutionary potential of populations, genealogical data from nuclear loci are essential, and the inclusion of other nuclear markers, i.e. single copy nuclear polymorphic (scnp) sequences, is clearly needed. Four major uncertainties for nuclear DNA analyses of populations have been facing us, i.e. the availability of scnp markers for carrying out such analysis, technical laboratory hurdles for resolving haplotypes, difficulty in data analysis because of recombination, low divergence levels and intraspecific multifurcation evolution, and the utility of scnp markers for addressing population-genetic questions. In this review, we discuss the availability of highly polymorphic single copy DNA in the nuclear genome, describe patterns and rate of evolution of nuclear sequences, summarize past empirical and theoretical efforts to recover and analyse data from scnp markers, and examine the difficulties, challenges and opportunities faced in such studies. We show that although challenges still exist, the above-mentioned obstacles are now being removed. Recent advances in technology and increases in statistical power provide the prospect of nuclear DNA analyses becoming routine practice, allowing allele-discriminating characterization of scnp loci and microsatellite loci. This certainly will increase our ability to address more complex questions, and thereby the sophistication of genetic analyses of populations.

Journal ArticleDOI
TL;DR: In this paper, the authors show that pre-rifting granitoids are widespread in the Yangtze craton, South China, and they exhibit no temporal or spatial zonation, hence no simple genetic relationship can be established between the different granitoid types and geodynamic environments, as suggested previously.

Journal ArticleDOI
TL;DR: It has been proved that the reduct of a covering is the minimal covering that generates theSame covering lower approximation or the same covering upper approximation, so this concept is also a technique to get rid of redundancy in data mining.

Journal ArticleDOI
TL;DR: In this article, the spatial patterns and temporal variation of land-use change during 1995-2000 are studied by using the Landsat TM digital images, supported by the 1km GRID data of land use change and the comprehensive characters of physical, economic and social features.
Abstract: It is more and more acknowledged that land-use/cover dynamic change has become a key subject urgently to be dealt with in the study of global environmental change. Supported by the Landsat TM digital images, spatial patterns and temporal variation of land-use change during 1995 –2000 are studied in the paper. According to the land-use dynamic degree model, supported by the 1km GRID data of land-use change and the comprehensive characters of physical, economic and social features, a dynamic regionalization of land-use change is designed to disclose the spatial pattern of land-use change processes. Generally speaking, in the traditional agricultural zones, e.g., Huang-Huai-Hai Plains, Yangtze River Delta and Sichuan Basin, the built-up and residential areas occupy a great proportion of arable land, and in the interlock area of farming and pasturing of northern China and the oases agricultural zones, the reclamation of arable land is conspicuously driven by changes of production conditions, economic benefits and climatic conditions. The implementation of “returning arable land into woodland or grassland” policies has won initial success in some areas, but it is too early to say that the trend of deforestation has been effectively reversed across China. In this paper, the division of dynamic regionalization of land-use change is designed, for the sake of revealing the temporal and spatial features of land-use change and laying the foundation for the study of regional scale land-use changes. Moreover, an integrated study, including studies of spatial pattern and temporal process of land-use change, is carried out in this paper, which is an interesting try on the comparative studies of spatial pattern on change process and the change process of spatial pattern of land-use change.

Journal ArticleDOI
TL;DR: Current strategies for reducing sludge production based on these mechanisms: lysis-cryptic growth, uncoupling metabolism, maintenance metabolism, and predation on bacteria are reviewed.

Journal ArticleDOI
TL;DR: Quantile regression offers a more complete statistical model than mean regression and now has widespread applications as mentioned in this paper and provides a review of this technique and discusses some typical application areas, as well as various approaches to estimation.
Abstract: Summary. Quantile regression offers a more complete statistical model than mean regression and now has widespread applications. Consequently, we provide a review of this technique. We begin with an introduction to and motivation for quantile regression. We then discuss some typical application areas. Next we outline various approaches to estimation. We finish by briefly summarizing some recent research areas.

Journal ArticleDOI
TL;DR: In this paper, a nanostructured surface layer was formed on an AISI 304 stainless steel with low stacking-fault energy by means of the surface mechanical attrition treatment (SMAT).

Journal ArticleDOI
04 Dec 2003-Neuron
TL;DR: It is reported that ATP released from astrocytes as a result of neuronal activity can also modulate central synaptic transmission, and neuron-glia crosstalk may participate in activity-dependent synaptic modulation.

Journal ArticleDOI
TL;DR: In China, the geological background level of heavy metal is low, but with the activity of humans, soil, water, air, and plants are polluted by heavy metals in some cases and even affect human health through the food chain.
Abstract: Goal, Scope and Background. Heavy metal is among one of the pollutants, which cause severe threats to humans and the environment in China. The aim of the present review is to make information on the source of heavy metal pollution, distribution of heavy metals in the environment, and measures of pollution control accessible internationally, which are mostly published in Chinese. Methods. Information from scientific journals, university journals and governmental releases are compiled focusing mainly on Cd, Cu, Pb and Zn. Partly Al, As, Cr, Fe, Hg, Mn and Ni are included also in part as well. Results and Discussion. In soil, the average contents of Cd, Cu, Pb and Zn are 0.097, 22.6, 26.0 and 74.2 mg/kg, respectively. In the water of. the Yangtze River Basin, the concentrations of Cd, Cu, Pb and Zn are 0.080, 7.91, 15.7 and 18.7 pg/L, respectively. In reference to human activities, the heavy metal pollution comes from three sources: industrial emission, wastewater and solid waste. The environment such as soil, water and air were polluted by heavy metals in some cases. The contents of Cd, Cu, Pb and Zn even reach 3.16, 99.3, 84.1 and 147 mg/kg, respectively, in the soils of a wastewater irrigation zone. These contaminants pollute drinking water and food, and threaten human health. Some diseases resulting from pollution of geological and environmental origin, were observed with long-term and non-reversible effects. Conclusions. In China, the geological background level of heavy metal is low, but with the activity of humans, soil, water, air, and plants are polluted by heavy metals in some cases and even affect human health through the food chain. Recommendations and Outlook. To remediate and improve environmental quality is a long strategy for the polluted area to keep humans and animals healthy. Phytoremediation would be an effective technique to remediate the heavy metal pollutions.

Journal ArticleDOI
TL;DR: In this article, the authors measured the organic carbon and elemental carbon (EC) in atmospheric particles at 8 sites in four cities (Hong Kong, Guangzhou, Shenzhen and Zhuhai) of Pearl River Delta Region (PRDR), China during two winter months (January and February, 2002).