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Community Dynamics of Seed Rain in Mixed Evergreen Broad-leaved and Deciduous Forests in a Subtropical Mountain of Central China

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Journal of Integrative Plant Biology 2007年第9期49卷 1294-1303页

作者： Ze-hao Shen yuan-yuan Tang Nan lü Jun Zhao Dao-Xing li Gong-Fang Wang Department of Ecology College of Environmental Sciences the Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 China National Dalaoling Forest Park Yichang 435000 China

Seed dispersal is a key process within community dynamics. The spatial and temporal variations of seed dispersal and the interspecific differences are crucial for understanding species coexistence and community dynamics. This might also hold for the mixed evergreen broadleaved and deciduous forests in the mountains of subtropical China, but until now little existing knowledge is available for this question. In 2001, we chose to monitor the seed rain process of our mixed evergreen broad-leaved and deciduous forest communities in Mount Dalaoling National Forest Park, yichang, Hubei Province, China. The preliminary analyses show obvious variations in seed rain density, species compositions and timing of seed rain among four communities. The average seed rain densities of the four communities are 2.43 ± 5.15, 54.13 ±182.75, 10.05 ±19.30 and 24.91 ± 58.86 inds/m^2, respectively; about one tenth the values in other studies in subtropical forests of China. in each community, the seed production is dominated by a limited number of species, and the contributions from the others are generally minor. Fecundity of evergreen broadleaved tree species is weaker than deciduous species. The seed rain of four communities begins earlier than September, and stops before December, peaking from early September to late October. The beginning date, ending date and peak times of seed rain are extensively varied among the species, indicating different types of dispersal strategies. According to the existing data, the timing of seed rain is not determined by the climate conditions in the same period, while the density of seed rain may be affected by the disturbances of weather variations at a finer temporal resolution.

关键词： interspecific difference Mount Dalaoling mountain mixed evergreen broad-leaved and deciduous forests seed rain species composition weather effect.

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Progress in TIllING as a tool for functional genomics and improvement of crops

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Journal of Integrative Plant Biology 2014年第5期56卷 425-443页

作者： liang Chen liugen hao Martin A. J. Parry Andrew l. Phillips yin-Gang Hu State Key laboratory of Crop Stress Biology in Arid Areas and College of Agronomy Northwest A&F University Department of Plant Biology and Crop Science Rothamsted Research Institute of Water Saving Agriculture in Arid Regions of China Northwest A&F University

Food security is a global concern and substantial yield increases in crops are required to feed the growing world population. Mutagenesis is an important tool in crop improvement and is free of the regulatory restrictions imposed on genetically modified organisms. Targeting Induced local lesions in Genomes（TIllING）, which combines traditional chemical mutagenesis with high‐throughput genome‐wide screening for point mutations in desired genes, offers a powerful way to create novel mutant alleles for both functional genomics and improvement of crops. TIllING is generally applicable to genomes whether small or large, diploid or evenallohexaploid, and shows great potential to address the major challenge of linking sequence information to the function of genes and to modulate key traits for plant breeding. TIllING has been successfully applied in many crop species and recent progress in TIllING is summarized below, especially on the developments in mutation detection technology, application of TIllING in gene functional studies and crop breeding. The potential of TIllING/EcoTIllING for functional genetics and crop improvement is also discussed. Furthermore, a small‐scale forward strategy including backcross and selfing was conducted to release the potential mutant phenotypes masked in M2（or M3） plants.

关键词： Crop breeding functional genomics mutation detection TIllING

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Monitoring of renal ischemia reperfusion injury in rabbits by ultrasonic contrast and its relationship with expression of VEGF in renal tissue

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Asian Pacific Journal of Tropical Medicine 2016年第2期9卷 186-190页

作者： Peng hao Department of Ultrasound Huai'an First People's Hospital Nanjing Medical University

Objective: To evaluate the renal ischemia reperfusion injury(IRI) in rabbits using the ultrasonic contrast technique and discuss the clinical value of ultrasonic contrast technique in the diagnosis of renal IRI by comparing the time-intensity curve of renal cortex and the expression of vascular endothelial growth factor(VEGF) of renal tissue. Methods: Twenty 3-month-old New Zealand rabbits were randomly divided into 4 groups, namely Ctrl group, IRI-12 h, IRI-24 h and IRI-48 h groups. The two dimensional gray-scale ultrasonography was employed to determine and mark the position of rabbit kidney. Rabbits were given the intraperitoneal anesthesia with 20% urethane with the dosage of 5 m l/kg. The aseptic operation was performed after the local skin disinfection in the area of both kidneys. The right kidney of animals in the control group was excised without any treatment for the left kidney. After excising the right kidney of animals in groups of IRI-12 h, IRI-24 h and IRI-48 h, the aneurysm clip was used to clip the renal pedicle vessel of left kidney, in order to simulate the ischemia. Because of the tissue ischemia, it could be seen that the color of kidney was changed from bright red to dark red, which indicated the successful modeling of ischemia. The aneurysm clip was released after one hour of maintaining the ischemia. Then the kidney turned out to be bright red from dark red, which indicated that the reperfusion was completed. Taking this moment as the time of ischemia reperfusion, the wound was stitched up. A total of 12, 24 and 36 h after the operation, the two-dimensional and color Doppler flow imaging and ultrasonic contrast were employed for the examination. The dynamic changes of ultrasonic contrast were recorded. The quantitative analysis software(Qontra Xt) was adopted to analyze the time-intensity curve of echo at different positions of renal cortex. After the ultrasonic contrast testing, rabbits were put to death. The renal cortex tissue was isolated

关键词： Ischemia reperfusion injury Kidney Ultrasonic contrast VEGF

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NanoSIMS analytical technique and its applications in earth sciences

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Science China Earth Sciences 2015年第9期58卷 1758-1767页

作者： yANG Wei HU Sen ZHANG JianChao hao Jialong lIN yangTing Key laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences

Despite the significant improvement on spatial resolution, NanoSIMS still preserves relatively high mass resolution, sensitivity, and analytical precision. It has become an important analytical platform to determine chemical compositions of solid materials, and has been widely used in space, earth, life, and materials sciences, etc. By using a Cs＋ ion beam with a size as small as 50 nm scanning over sample surfaces, we are able to obtain high spatial resolution images of up to 7 species simultaneously. When utilizing Faraday cup, high analytical precision of 0.3‰-0.5‰ （1SD） for C, O and S isotopic analysis can be achieved. Although this precision level is still lower than that of conventional SIMS, it already meets the major requirements of Earth Sciences. In 2011, the first NanoSIMS of China （Cameca NanoSIMS 50l） was installed at Institute of Geology and Geophysics, Chinese Academy of Sciences. Based on the working mechanism and analytical modes of the instrument, this paper will systematically introduce the analytical methods established with the NanoSIMS and their potential applications in earth sciences. These methods include trace element distribution images in mineral zoning, high spatial resolution （2-5/am） Pb-Pb and U-Pb dating, water content and H isotopic analysis for silicate glass and apatite, C isotopic analysis for diamond and graphite, O isotopic analysis for carbonate, S isotopic analysis for sulfides. In addition, the specific requirements for sample preparation will also be introduced in order to facilitate domestic earth scientists＇ use.

关键词： NanoSIMS micro-beam analysis elemental distribution images Pb-Pb and U-Pb dating stable isotopes

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Physical statistical algorithm for precipitable water vapor inversion on land surface based on multi-source remotely sensed data

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Science China Earth Sciences 2015年第1期58卷 2340-2352页

作者： WANG yongQian SHI JianCheng WANG hao FENG Wenlan WANG yanJun College of Environmental and Resource Science Chengdu University of Information Technology State Key laboratory of Remote Sensing Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Chongqing Institute of Meteorological Sciences College of Electronic Engineering Chengdu University of Information Technology

Water vapor plays a crucial role in atmospheric processes that act over a wide range of temporal and spatial scales, from global climate to micrometeorology. The determination of water vapor distribution in the atmosphere and its changing pattern is very important. Although atmospheric scientists have developed a variety of means to measure precipitable water vapor(PWV) using remote sensing data that have been widely used, there are some limitations in using one kind satellite measurements for PWV retrieval over land. In this paper, a new algorithm is proposed for retrieving PWV over land by combining different kinds of remote sensing data and it would work well under the cloud weather conditions. The PWV retrieval algorithm based on near infrared data is more suitable to clear sky conditions with high precision. The 23.5 GHz microwave remote sensing data is sensitive to water vapor and powerful in cloud-covered areas because of its longer wavelengths that permit viewing into and through the atmosphere. Therefore, the PWV retrieval results from near infrared data and the indices combined by microwave bands remote sensing data which are sensitive to water vapor will be regressed to generate the equation for PWV retrieval under cloud covered areas. The algorithm developed in this paper has the potential to detect PWV under all weather conditions and makes an excellent complement to PWV retrieved by near infrared data. Different types of surface exert different depolarization effects on surface emissions, which would increase the complexity of the algorithm. In this paper, MODIS surface classification data was used to consider this influence. Compared with the GPS results, the root mean square error of our algorithm is 8 mm for cloud covered area. Regional consistency was found between the results from MODIS and our algorithm. Our algorithm can yield reasonable results on the surfaces covered by cloud where MODIS cannot be used to retrieve PWV.

关键词： satellite remote sensing precipitable water vapor visible/near infrared thermal infrared microwave

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Applications of graphene-based materials in environmental protection and detection

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Chinese Science Bulletin 2013年第22期58卷 2698-2710页

作者： lü MeiJiao lI Jing yANG Xuyu ZHANG ChangAn yANG Jia HU hao WANG XianBao Key laboratory for the Green Preparation and Application of Functional Materials Ministry of Education Faculty of Materials Science and Engineering Hubei University

Many efficient adsorbents and sensors based on graphene and functionalized graphene have been constructed for the removal and detection of environmental pollutants due to its unique physicochemical properties. In this article, recent research achievements are reviewed on the application of graphene-based materials in the environmental protection and detection. For environmental protection, modified graphene can adsorb heavy metal ions in a high efficiency and selectivity, and thus reduces them to metals for recycling. High adsorption capacity of graphene-based materials to kinds of organic pollutants in water was also presented. Several graphene-based sensors with high limit of detection were reported to detect heavy metal ions, toxic gases and organic pollutants in environment. Finally, a perspective on the future challenge of adsorbents and detection devices based on graphene is given.

关键词：改性石墨环境保护检测限材料应用重金属离子有机污染物物理化学性质

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Exfoliated Mg–Al–Fe layered double hydroxides/polyether sulfone mixed matrix membranes for adsorption of phosphate and fluoride from aqueous solutions

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Journal of Environmental Sciences 2018年第8期30卷 63-73页

作者： Zhiqian Jia Shuang hao Xiaoyu lu lab for Membrane Science and Technology College of Chemistry Beijing Normal University

Mg–Al–Fe layered double hydroxides（lDHs） were exfoliated and incorporated in polyether sulfone membranes for the removal of phosphate and fluoride for the first time. The exfoliation methods, coagulation bath, lDH amount, interfering ions, adsorption isotherm,desorption and reuse of the membranes were investigated. It was found that lDHs could be quickly exfoliated in formamide/N,N-dimethylformamide（DMF） solvent mixtures with sodium carboxymethyl cellulose as a stabilizer. The membranes displayed much higher adsorption capacity for phosphate（5.61 mg/g） and faster adsorption rate than the unexfoliated materials. With increased DMF content in the coagulation bath, the static and dynamic adsorption capacity rose. Interference from Cl-and SO4^（2-）（50 mg/l） on adsorption of phosphates was not apparent. The membranes displayed excellent reusability in dynamic adsorption/desorption. The membranes also showed high adsorption capacity for fluorides（1.61 mg/g）.

关键词： layered double hydroxides Membrane Adsorption Phosphate Fluoride Exfoliation

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A green and effective corrosion inhibitor of functionalized carbon dots

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Journal of Materials Science & Technology 2019年第10期35卷 2243-2253页

作者： yuwei ye Dongping yang hao Chen The Institute of Engineering Research Jiangxi University of Science and TechnologyGanzhou341000China Key laboratory of Marine Materials and Related Technology Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo315201China

In this work, a green and effective corrosion inhibitor of functionalized carbon dots(FCDs) was synthesized by the conjugation of imidazole and citric acid carbon dots(CA-CDs). The corrosion inhibition behavior of FCDs for Q235 steel in 1 M HCl solution was systematically investigated by electrochemical analysis, corrosion morphology and adsorption isotherm. The electrochemical results implied that the as-prepared FCDs inhibitor could effectively suppress the corrosion of Q235 steel in 1 M HCl solution. At the same time, the inhibition efficiency of steel in 1 M HCl solution was more than 90% when the inhibitor concentration exceeded 100 mg/l. This excellent property was attributed to the coverage of adsorption film on the steel surface, which conformed to the langmuir adsorption model. In addition, the analysis of adsorption isotherm displayed that the adsorption mechanism was the physicochemical interaction at the steel/solution interface.

关键词： Q235 steel Carbon dots Adsorption HCl solution

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Effect of sub-acute exposure to TiO_2 nanoparticles on oxidative stress and histopathological changes in Juvenile Carp (Cyprinus carpio)

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Journal of Environmental Sciences 2009年第10期21卷 1459-1466页

作者： hao linhua WANG Zhenyu XING Baoshan College of Environmentul Science and Engineering Ocean University of China Qingdao 266100 China. First Institute of Oceanography State Oceanic Administration Qingdao 266061 China. Department of Plant Soil and Insect Sciences University of Massachusetts Amherst MA 01003 USA.

Increasing application of nanotechnology highlights the need to clarify and understand nanotoxicity. Mammalian and in vitro studies have raised concerns about the toxicity of titanium dioxide nanoparticles （TiO2-NPs）, but there are limited data on ecotoxicity to aquatic organisms. In this work, the sub-acute toxicity of TiO2-NPs to carp （Cyprinus carpio） was assessed. Superoxide dismutase （SOD）, catalase （CAT） and peroxidase （POD） activities and lipid peroxidation （lPO） levels in liver, gill and brain tissues of carps varied with concentration of TiO2-NPs suspensions and exposure time （up to 8 d）. As a result, 100 and 200 mg/l TiO2-NPs caused statistically significant decrease in SOD, CAT and POD activities and significant increase in lPO levels in tissues （P 〈 0.05）, suggesting that the fish exposed to these two concentrations of TiO2-NPs suffered from the oxidative stress. The extent of depletion of antioxidant enzymes activities and the elevation of lPO in the liver was the greatest, indicating that the liver might be the most susceptible organ to TiO2-NPs exposure. In addition, carps had gill pathologies including edema and thickening of gill lamellae as well as gill filaments, and liver pathologies including necrotic and apoptosis hepatocytes after exposed to 100 and 200 mg/l TiO2-NPs for 20 d. These results indicated a potential risk from TiO2-NPs released into the aqueous environment.

关键词： TiO2 nanoparticles carp sub-acute toxicity oxidative stress histopathology

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Synthesis and Characterization of Tb-incorporated Apatite Nano-scale Powders

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Journal of Materials Science & Technology 2012年第9期28卷 773-778页

作者： l.J. Sun P.F. Ni D.G. Guo C.Q. Fang J. Wang F. yang X.F. Huang y.Z. hao H. Zhu K.W. Xu State Key laboratory for Mechanical Behavior of Materials School of Materials Science and Engineering Xi'an Jiaotong University Xi'an 710049 China School of Printing and Packaging Engineering Xi'an University of Technology Xi'an 710048 China Xi'an University of Arts and Science Xi'an 710065 China

Nano-scale Tb-incorporated apatite （nano-Tb-AP） particles with different Tb contents （Tb/（Tb＋Ca）） of 0%, 5%, 10% and 20% were synthesized through a simple wet chemical method in this study. The crystal structure, thermal stabilities, chemical groups, crystal morphologies and crystal sizes of the nano--Tb-AP particles were characterized by X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR）, and transmission electron microscopy （TEM）, respectively. It was found that lattice constants, particle sizes, crystalline and thermal stability varied with the doped Tb contents. With the increasing of Tb content, the lattice constants, particle size, length/diameter ratio, crystalline and thermal stability of nano-Tb-AP gradually decrease. Especially, almost all the 20%Tb-AP nano particles had been decomposed at 1200 ℃ while only a few of the decomposed products （β-TCP） were detected in the Tb-free nano apatite powders： This kind of nano-scale Tb-incorporated apatite exhibits an extremely potential clinic application because it integrates both the excellent biological functions of Tb element and apatite in human body.

关键词： Nano-scale powder Terbium (Tb) Wet chemical approach Apatite Biomedical materials

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