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Nano Research 2016年第3期9卷 622-632页

作者： Yang Gao Bo Wang Yanyu Lei Boon K. Teo Zhigang Wang Institute of Atomic and Molecular Physics Jilin University Changchun 130012 China Jilin Provincial Key Laboratory of AppliedAtomic and Molecular Spectroscopy Jilin University Changchun 130012 China College of Chemistry and Molecular Engineering Peking University Beijing 100871 China College of Chemistry and Chemical Engineering Kiamen University Xiamen 361005 China Beijing Computational Science Research Center Beijing 100084 China

Actinide elements encaged in a superatomic cluster can exhibit unique properties due to their hyperactive valence electrons. Herein, the electronic and spectroscopic properties of Th@Au14 are predicted and compared with that of the isoelectronic entities [Ac@Au14]- and [Pa@Au14]＋ using density functional theory. The calculation results indicate that these clusters all adopt a closed- shell superatomic 18-electron configuration of the 1S21p61D10 Jellium state. The absorption spectrum of Th@Au14 can be interpreted by the Jelliumatic orbital model. In addition, calculated spectra of pyridine-Th@Au14 complexes in the blue laser band exhibit strong peaks attributable to charge transfer （CT） from the metal to the pyridine molecule. These charge-transfer bands lead to a resonant surface-enhanced Raman scattering （SERS） enhancement of -104. This work suggests a basis for designing and synthesizing SERS substrate materials based on actinide-embedded gold superatom models.

关键词： actinide element DFT calculation gold nanoparticle superatomic orbital surface-enhanced Ramanscattering

Copper Delivery by the Copper Chaperone for Chloroplast and Cytosolic Copper/Zinc- Superoxide Dismutases： Regulation and Unexpected Phenotypes in an Arabidopsis Mutant

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Molecular Plant 2009年第6期2卷 1336-1350页

作者： Christopher M. Cohu Salah E. Abdel-Ghany Kathryn A. Gogolin Reynolds Alexander M. Onofrio Jared R. Bodecker Jeffrey A. Kimbrel Krishna K. Niyogi Marinus Pilon Biology Department Colorado State University Fort Collins CO 80523-1878 USA Department of Plant and Microbial Biology University of California Berkeley CA 94720-3102 USA

Copper （Cu） is an important mineral nutrient found in chloroplasts as a cofactor associated with plastocyanin and Cu/Zn superoxide dismutase （Cu/ZnSOD）. Superoxide dismutases are metallo-enzymes found in most oxygenic organisms with proposed roles in reducing oxidative stress. Several recent studies in Arabidopsis have shown that microRNAs and a SQUAMOSA promoter binding protein-like7 （SPL7） transcription factor function to down-regulate the expression of many Cu-proteins, including Cu/ZnSOD in both plastids and the cytosol, during growth on low Cu. Plants contain the Cu Chaperone for SOD （CCS） that delivers Cu to Cu/ZnSODs, and, in Arabidopsis, both cytosolic and plastidic CCS versions are encoded by one gene. In this study, we demonstrate that Arabiclopsis CCS transcript levels are regulated by Cu, mediated by microRNA 398 that was not previously predicted to target CCS. The microRNA target site is conserved in CCS of Oryza sativa. The data suggest that Cu-regulated microRNAs may have more mRNA targets than was previously predicted. A CCS null mutant has no measurable SOD activity in the chloroplast and cytosol, indicating an absolute requirement for CCS. When the CCS null mutant was grown on high Cu media, it lacked both Fe superoxide dismutase （FeSOD） and Cu/ZnSOD activity. However, this did not lead to a visual phenotype and no photosynthetic deficiencies were detected, even after high light stress. These results indicate that Cu/ZnSOD is not a pivotal component of the photosynthetic anti-oxidant system during growth in laboratory conditions.

关键词： Chloroplast photosynthesis copper homeostasis superoxide dismutase microRNA.

Generalized and species-specific prediction models for aboveground biomass in semi-steppe rangelands

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Journal of Plant Ecology 2019年第3期12卷 428-437页

作者： Anvar Sanaei Arshad Ali Khaled Ahmadaali Esfandiar Jahantab Department of Reclamation of Arid and Mountainous Regions Natural Resources FacultyUniversity of TehranKarajPO Box 31585-4314Iran Spatial Ecology Lab School of Life SciencesSouth China Normal UniversityGuangzhouGuangdong 510631China Department of Range and Watershed Management Faculty of Agricultural SciencesFasa UniversityFasaIran

Aims The accurate estimation of aboveground biomass in vegetation is critical for global carbon *** models provide an easy estimation of aboveground biomass at large spatial and temporal ***,only few prediction models are available for aboveground biomass in rangelands,as compared with *** addition to the development of prediction models,we tested whether such prediction models vary with plant growth forms and life spans,and with the inclusion of site and/or quadrat-specific *** we collected dataset of aboveground biomass from destructive harvesting of 8088 individual plants belonging to 79 species in 735 quadrats across 35 sites in semi-steppe rangelands in Iran.A logarithmic transformation of the power-law model was used to develop simple prediction models for the easy estimation of above-ground biomass using plant coverage and vegetation density as predictors for the species-specific model,multispecies and plants of different growth forms and life *** addition,additive and multiplicative linear regression models were developed by using plant coverage and one categorical variable from the site and/or quadrat-specific *** Findings The log-transformed power-law model based on plant coverage pre-cisely predicted aboveground biomass across the whole dataset for ei-ther most of the species-specific model,multispecies or plants of the same growth forms(shrubs,forbs or graminoids)and life spans(annuals,biennials or perennials).The addition of vegetation density as a single or in a compound predictor variable had relatively poor performance com-pared with the model having plant coverage *** generalizing at the levels of plant group forms and/or life spans did not substantially enhance the model-fit and validation of the plant coverage-based mul-tispecies model,the inclusion of plant growth forms or life spans as a categorical predictor variable had performed *** models in this study will

关键词： ecosystem functioning aboveground biomass plant coverage plant life spans prediction models vegetation density

Recruitment and functionality traits as bioindicators of ecological restoration success in the Lurg Hills district,Victoria,Australia

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Ecological Processes 2013年第1期2卷 286-296页

作者： Kristin Monie Singarayer Florentine Grant Palmer Centre for Environmental Management School of ScienceInformation Technology and EngineeringUniversity of BallaratPO Box 663BallaratVictoriaAustralia

Introduction:The Regent Honeyeater Project commenced ecological restoration in the Lurg district in 1994,with an aim to restore habitats for the critically endangered Regent Honeyeater Anthochaera phrygia and a range of other threatened and declining *** this context,our study aimed to explore whether plant reproduction can be an effective measure of ecological restoration ***:Evaluation involved comparing attributes at unrestored,restored and remnant sites to establish whether sites displayed evidence of a clear restoration *** age classes(unrestored,4–6 years old,8–10 years old,12–14 years old and remnant areas)and two landforms(upper hills and lower hills)were *** diversity of woody plant species—which have easily recognisable reproductive material and which all recruit seedlings—provides easily measured parameters that have the potential to allow the determination of early establishment success and long-term ecological development of restored ***:Restoration plantings developed in a hybrid state towards a benchmark in the lower hills;seedling species composition differed significantly among age classes,increasing in similarity with time since restoration,with some divergence from the target *** of functional groups with reproductive outputs was also significantly different among age classes;however,a restoration trajectory was only evident in the upper hills where sites converged towards the target ***:Divergence or deviation from the restoration trajectory was not deemed to be a restoration failure,as the variety of functional groups with fruits and diversity of seedlings recruiting indicated a potential increase in resilience in the future due to greater variability across the *** recruitment was effective in detecting development trends towards a restoration target in this study and therefore may be a useful measure that contributes to determining ecological

关键词： Restoration Assessment Ecological development Trajectory Monitoring

Conservation of IRE1-Regulated bZIP74 mRNA Unconventional Splicing in Rice （Oryza sativa L.） Involved in ER Stress Responses

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Molecular Plant 2012年第2期5卷 504-514页

作者： Sun-Jie Lu Zheng-Ting Yang Ling Sun Le Sun Ze-Ting Song Jian-Xiang Li State Key Laboratory of Genetic Engineering Institute of Plant BiologySchool of Life SciencesFudan UniversityShanghai200433China

Protein folding in the endoplasmic reticulum （ER） is a fundamental process in plant cells that is vulnerable to many environmental stresses. When unfolded or misfolded proteins accumulate in the ER, the well-conserved unfolded protein response （UPR） is initiated to mitigate the ER stress by enhancing the protein folding capability and/or accelerating the ER-associated protein degradation. Here, we report the conservation of the activation mechanism of OsbZIP74 （also known as OsbZIP50）, an important ER stress regulator in monocot plant rice （Oryza sativa L.）. Under normal conditions, OsbZIP74 mRNA encodes a basic leucine-zipper transcription factor with a putative transmembrane domain. When treating with ER stress-inducing agents such as tunicamycin and DTT, the conserved double stem-loop structures of OsbZIP74 mRNA are spliced out. Thereafter, the resulting new OsbZIP74 mRNA produces the nucleus-localized form of OsbZIP74 protein, eliminating the hydrophobic region. The activated form of OsbZIP74 has transcriptional activation activity in both yeast cells and Arabidopsis leaf protoplasts. The induction of OsbZIP74 splicing is much suppressed in the OsIRE1 knock- down rice plants, indicating the involvement of OslRE1 in OsbZIP74 splicing. we also demonstrate that the unconventional splicing of OsbZIP74 mRNA is associated with heat stress and salicylic acid, which is an important plant hormone in systemic acquired resistance against pathogen or parasite.

关键词： mRNA unconventional splicing unfolded protein response bZIP transcription factor IRE1 heat stress salicylic acid (SA) Oryza sativa.

Mapping paddy rice distribution using multi-temporal Landsat imagery in the Sanjiang Plain, northeast China

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Frontiers of Earth Science 2016年第1期10卷 49-62页

作者： Cui JIN Xiangming XIAO Jinwei DONG Yuanwei QIN Zongming WANG Department of Microbiology and Plant Biology Center for Spatial Analysis University of Oklahoma Norman OK 73019 USA Institute of Biodiversity Sciences Fudan University Shanghai 200433 China Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130102 China

Information of paddy rice distribution is essential for food production and methane emission calculation. Phenology-based algorithms have been uti- lized in the mapping of paddy rice fields by identifying the unique flooding and seedling transplanting phases using multi-temporal moderate resolution （500m to 1 km） images. In this study, we developed simple algorithms to identify paddy rice at a fine resolution at the regional scale using multi-temporal Landsat imagery. Sixteen Landsat images from 2010-2012 were used to generate the 30 m paddy rice map in the Sanjiang Plain, northeast China-one of the major paddy rice cultivation regions in China. Three vegetation indices, Normalized Difference Vegetation Index （NDVI）, Enhanced Vegetation Index （EVI）, and Land Surface Water Index （LSWI）, were used to identify rice fields during the flooding/transplanting and ripening phases. The user and producer accuracies of paddy rice on the resultant Landsat-based paddy rice map were 90% and 94%, respectively. The Landsat-based paddy rice map was an improvement over the paddy rice layer on the National Land Cover Dataset, which was generated through visual interpretation and digitalization on the fine-resolution images. The agricultural census data substantially underreported paddy rice area, raising serious concern about its use for studies on food security.

关键词： phenology flooding transplanting ripening,land use

Quantification of Adventitial Vasa Vasorum Vascularization in Double-injury Restenotic Arteries

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Chinese Medical Journal 2015年第15期128卷 2090-2096页

作者： Meng Ye Bai-Gen Zhang Lan Zhang Hui Xie Hao Zhang Department of Vascular Surgery Ren Ji Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200127 China

Background：Accumulating evidence indicates a potential role of adventitial vasa vasorum （VV） dysfunction in the pathophysiology of ***,characterization ofVV vascularization in restenotic arteries with primary lesions is still *** this study,we quantitatively evaluated the response of adventitial VV to vascular injury resulting from balloon angioplasty in diseased ***：Primary atherosclerotic-like lesions were induced by the placement of an absorbable thread surrounding the carotid artery of New Zealand *** weeks following double-injury induced that was induced by secondary balloon dilation,three-dimensional patterns of adventitial VV were reconstructed;the number,density,and endothelial surface of VV were quantified using micro-computed *** and immunohistochemistry were performed in order to examine the development of intimal ***：Results from our study suggest that double injured arteries have a greater number of VV,increased luminal surface,and an elevation in the intima/media ratio （I/M）,along with an accumulation ofmacrophages and smooth muscle cells in the intima,as compared to sham or single injury arteries.I/M and the number of VV were positively correlated （R^2 =0.82,P 〈 0.001）.Conclusions：Extensive adventitial VV neovascularization occurs in injured arteries after balloon angioplasty,which is associated with intimal *** assessment of adventitial VV response may provide insight into the basic biological process of postangioplasty restenosis.

关键词： Angioplasty Micro-computed Tomography Restenosis Vasa Vasorum

Detection and monitoring of insect resistance to transgenic Bt crops

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Insect Science 2006年第2期13卷 73-84页

作者： FANGNENG HUANG Department of Entomology Louisiana State University AgCenter Baton Rouge Louisiana USA

Transgenic crops expressing Bacillus thuringiensis （Bt） endotoxins havebecome one of the most important tools for managing corn and cotton insect pests in the US and other countries. The widespread adoption of transgenic Bt crops could place a high degree of selection pressure on the target insect populations and accelerate development of resistance, raising concerns about the long-term durability of Bt plants as an effective pest management tool. Conservation of Bt susceptibility in insects has become one of the most active research areas in modern agriculture. One of the key factors for a successful Bt resistance management plan is to have a cost-effective monitoring system that can provide information on. （i） the initial Bt resistance allele frequencies at low levels in field insect populations; and （ii） early shifts in Bt resistance allele frequencies so that proactive measures for managing resistance can be deployed well before field control failures. Developing such a monitoring program has been difficult because：（i） resistance traits that occur at very low frequencies are hard to detect; （ii） many factors affect the sensitivity and accuracy of a Bt resistance monitoring program; and （iii） monitoring resistance is costly. Several novel methods for detecting Bt resistance alleles developed during the last decade have made a cost-effective monitoring system possible. Future studies should focus on how to improve and standardize the methodologies for insect sampling and Bt resistance detection.

关键词： Bt resistance management resistance monitoring transgenic plants

Quantification of clay minerals by combined EWA/XRD method——Application in Triassic reservoirs of the Morecambe Gas Field,East Irish Sea, UK

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Science China Earth Sciences 2001年第4期44卷 307-317页

作者：徐建红 T.R.Astin 潘懋 Department of Geography Peking University Beijing 100871 China PRIS Reading University RG6 6AB UK

Illite has been considered the main constraint on permeability in the Morecambe Gas Field, East Irish Sea, UK. Previous research has emphasized the morphology rather than the amount of clay minerals. By applying a new method of clay mineral quantification, EWA/XRD, and applying statistical analysis methods, we are able to establish a quantitative model of illite distribution in the field. The result also leads to a better understanding of permeability distribution in reservoir sandstones.

关键词： clay mineral, quantification, EWA, XRD, Triassic, Morecambe.

Neuronal firing in the ventrolateral thalamus of patients with Parkinson＇s disease differs from that with essential tremor

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Chinese Medical Journal 2010年第6期123卷 695-701页

作者： CHEN Hai ZHUANG Ping MIAO Su-hua YUAN Gao ZHANG Yu-qing LI Jian-yu LI Yong-jie Beijing Institute of Functional Neurosurgery Department of NeurologyXuanwu HospitalCapital Medical UniversityKey Laboratory of Neurodegenerative DiseasesMinistry of EducationBeijing 100053China

Background Although thalamotomy could dramatically improve both parkinsonian resting tremor and essential tremor （ET）, the mechanisms are obviously different. This study aimed to investigate the neuronal activities in the ventrolateral thalamus of Parkinson＇s disease （PD） and ET. Methods Thirty-six patients （PD： 20, ET： 16） were studied. Microelectrode recordings in the ventral oral posterior （Vop）and the ventral intermediate nucleus （Vim） of thalamus was performed on these patients who underwent *** （EMG） was recorded simultaneously on the contralateral limbs to surgery. Single unit analysis and the interspike intervals （ISIs） were measured for each neuronal type. ISI histogram and auto-correlograms were constructed to estimate the pattern of neuronal firing. Mann-Whitney test and Kruskal-Wallis （K-W） test were used to compare the mean spontaneous firing rate （MSFR） of neurons of PD and ET patients. Results Three hundred and twenty-three neurons were obtained from 20 PD trajectories, including 151 （46.7%） tremor related neuronal activity, 74 neurons （22.9%） with tonic firing, and 98 （30.4%） neurons with irregular discharge. One hundred and eighty-seven neurons were identified from 16 ET trajectories including 46 （24.6%） tremor-related neuronal activity, 77 （41.2%） neurons with tonic firing, and 64 neurons （34.2%） with irregular discharge. The analysis of MSFR of neurons with tonic firing was 26.7 （3.4-68.3） Hz （n=74） and that of neurons with irregular discharge （n=98） was 13.9 （3.0-58.1） Hz in PD; whereas MSFR of neurons with tonic firing （n=77） was 48.8 （19.0-135.5） Hz and that of neurons with irregular discharge （n=64） was 26.3 （8.7-84.7） Hz in ET. There were significant differences in the MSFR of two types of neuron for PD and ET （K-W test, both P〈0.05）. Significant differences in the MSFR of neuron were also obtained from Vop and Vim of PD and ET （16.3 Hz vs. 34.8 Hz, 28.0 Hz vs. 49.9 Hz）（K-W test, both P 〈0.05）, respectively. Conclusi

关键词： Parkinson disease essential tremor ventrolateral thalamic nucleus microelectrodes