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| 1 | The spatial pattern of grassland aboveground biomass on Xizang Plateau and its climatic controls显示文摘Aims Grassland is the most widely distributed vegetation type on the Xizang Plateau.Accurate remote sensing estimation of the grass-land aboveground biomass(AGB)in this region is influenced by the types of vegetation indexes(VIs)used,the grain size(resolution)of the remote sensing data and the targeted ecosystem features.This study attempts to answer the following questions:(i)Which VI can most accurately reflect the grassland AGB distribution on the Xizang Plateau?(ii)How does the grain size of remote sensing imagery affect AGB reflection?(iii)What is the spatial distribution pattern of the grassland AGB on the plateau and its relationship with the climate?Methods We investigated 90 sample sites and measured site-specific AGBs using the harvest method for three grassland types(alpine meadow,alpine steppe and desert steppe).For each sample site,four VIs,namely,Normalized Difference VI(NDVI),Enhanced VI,Normalized Difference Water Index(NDWI)and Modified Soil-Adjusted VI(MSAVI)were extracted from the Moderate Resolution Imaging Spectroradiometer(MODIS)products with grain sizes of 250 m and 1 km.Linear regression models were employed to iden-tify the best estimator of the AGB for the entire grassland and the three individual grassland types.Paired Wilcoxon tests were applied to assess the grain size effect on the AGB estimation.General linear models were used to quantify the relationships between the spatial distribution of the grassland AGB and climatic factors.Important Findings The results showed that the best estimator for the entire grass-land AGB on the Xizang Plateau was MSAVI at a 250 m grain size(MSAVI_(250 m)).For each individual grassland type,the best estimator was MSAVI at a grain size of 250 m for alpine meadow,NDWI at a grain size of 1 km for alpine steppe and NDVI at a grain size of 1 km for desert steppe.The explanation ability of each VI for the grassland AGB did not significantly differ for the two grain sizes.Based on the best fit model(AGB=−10.80+139.13 MSAVI_(250 m)),the spatial pattern of the grassland AGB on the plateau was characterized.The AGB varied from 1 to 136 g m^(−2).Approximately 59%of total spatial variation in the AGB for the entire grassland was explained by the combination of the mean annual precipitation(MAP)and mean annual temperature.The explanatory power of MAP was weaker for each individual grassland type than that for the entire grassland.This study illustrated the high efficiency of the VIs derived from MODIS data in the grassland AGB estimation on the Xizang Plateau due to the vegetation homogeneity within a 1×1 km pixel in this region.Furthermore,MAP is a primary driver on the spatial variation of AGB at a regional scale. | Yanbin Jiang Jian Tao Yongqi Huang Juntao Zhu Li Tian Yangjian Zhang | 2015 | Journal of Plant Ecology2015，8，1： | 6 |
| 2 | The Relationship between Melt Season Sea Ice over the Bering Sea and Summer Precipitation over Mid-Latitude East Asia显示文摘Independent datasets consistently indicate a significant correlation between the sea ice variability in the Bering Sea during melt season and the summer rainfall variability in the Lake Baikal area and Northeastern China.In this study,four sea ice datasets(HadISST1,HadISST2.2,ERA-Interim and NOAA/NSIDC)and two global precipitation datasets(CRU V4.01 and GPCP V2.3)are used to investigate co-variations between melt season(March−April−May−June,MAMJ)Bering Sea ice cover(BSIC)and summer(June−July−August,JJA)East Asian precipitation.All datasets demonstrate a significant correlation between the MAMJ BSIC and the JJA rainfall in Lake Baikal−Northeastern China(Baikal−NEC).Based on the reanalysis datasets and the numerical sensitivity experiments performed in this study using Community Atmospheric Model version 5(CAM5),a mechanism to understand how the MAMJ BSIC influences the JJA Baikal−NEC rainfall is suggested.More MAMJ BSIC triggers a wave train and causes a positive sea level pressure(SLP)anomaly over the North Atlantic during MAMJ.The high SLP anomaly,associated with an anti-cyclonic wind stress circulation anomaly,favors the appearance of sea surface temperature(SST)anomalies in a zonal dipole-pattern in the North Atlantic during summer.The dipole SST anomaly drives a zonally orientated wave train,which causes a high anomaly geopotential height at 500 hPa over the Sea of Japan.As a result,the mean East Asian trough moves westward and a low geopotential height anomaly occurs over Baikal−NEC.This prevailing regional low pressure anomaly together with enhanced moisture transport from the western North Pacific and convergence over Baikal−NEC,positively influences the increased rainfall in summer. | Yurun TIAN Yongqi GAO Dong GUO | 2021 | Advances in Atmospheric Sciences2021，38，6： | 4 |
| 3 | Emission inventories of NOx from commercial energy consumption in china,1995-1998显示文摘 | Tian Hezhong Lu Yongqi | 2002 | Environ Sci Technol2002，36，： | 1 |
| 4 | Emission inventories of NOx from commercial consumption in China,1995-1998显示文摘 | Hao Jiming Tian Hezhong Lu Yongqi | 2002 | Environ Sci Technol2002，36，4： | 1 |
| 5 | Emission inventories of NOx from commercial energy consumption in China, 1995~1998 显示文摘 | Hao Jiming Tian Hezhong Lu Yongqi | 2002 | Environmental Science & Technology2002，36，4： | 1 |
| 6 | Weakly-coupled mode division multiplexing over conventional multi-mode fiber with intensity modulation and direct detection显示文摘Multi-mode fiber(MMF)links are expected to greatly enhance capacity to cope with rapidly increasing data traffic in optical short-reach systems and networks.Recently,mode division multiplexing(MDM)over MMF has been proposed,in which different modes in MMF are utilized as spatial channels for data transmission.Stronglycoupled MDM techniques utilizing coherent detection and multiplex-input-multiplex-output(MIMO)digital signal processing(DSP)are complex and expensive for shortreach transmission.So the weakly-coupled approach by significantly suppressing mode coupling in the fiber and optical components has been proposed.In this way,the signals in each mode can be independently transmitted and received using conventional intensity modulation and direct detection(IM-DD).In this paper,we elaborate the key technologies to realize weakly-coupled MDM transmission over conventional MMF,including mode characteristic in MMF and weakly-coupled mode multiplexer/ demultiplexer(MUX/DEMUX).We also present the upto-date experimental results for weakly-coupled MDM transmission over conventional OM3 MMF.We show that weakly-coupled MDM scheme is promising for high-speed optical interconnections and bandwidth upgrade of already-deployed MMF links. | Juhao LI Zhongying WU Dawei GE Jinglong ZHU Yu TIAN Yichi ZHANG Jinyi YU Zhengbin LI Zhangyuan CHEN Yongqi HE | 2019 | Frontiers of Optoelectronics2019，12，1： | 1 |
| 7 | Advances in research on chemical constituents and pharmacological effects of Paecilomyces hepiali显示文摘Paecilomyces hepiali is a fungus with edible and pharmaceutic value,isolated from Ophiocordyceps sinensis.Its main bioactive constituents contain alkaloids,cyclic dipeptides,steroids,organic acids,and polysaccharides.Due to the huge development potential of P.hepiali in the field of food and medicine,it has been developed into a variety of products that cater to the needs of the public.In this paper,the chemical constituents and their pharmacological effects of P.hepiali are reviewed,which can provide reference for the development and application of P.hepiali. | Akang Dan Yujia Hu Ruyan Chen Xiangyang Lin Yongqi Tian Shaoyun Wang | 2021 | Food Science and Human Wellness2021，10，4： | 1 |
| 8 | Anthropogenic nitrogen oxides Emissions in china in the period1990- 1998显示文摘 | Tian Hezhong Lu Yongqi | 2001 | Abstracts of Papers of American Chemistry Society2001，221，11： | 1 |
| 9 | Direct measurement of microscopic strain distribution near a crack tip显示文摘 | S. Yongqi C. Corletto W. L. Bradley J. Tian | 1996 | Experimental Mechanics1996，，3： | 1 |
| 10 | In vivo anti-aging properties on fat diet-induced high fat Drosophila melanogaster of n-butanol extract from Paecilomyces hepiali显示文摘The purpose of this study was to explore the potential of the development and application of Paecilomyces hepiali,a fungus with edible and medicinal value,as a foodborne antioxidant and anti-aging agent.Its n-butanol extract(PHE)from rice cultures was selected for anti-aging experiment because of significant free radical scavenging activity in vitro.In vivo,PHE could significantly prolong the mean lifespan,50%survival days,and the maximum lifespan of Drosophila on a high-fat diet.It is amazing that the mean lifespan increased from 19.1 days to 32.9 days,50%survival days increased from 15.7 days to 34.3 days,and the maximum lifespan extended from 44.7 days to 52.7 days,when the high-fat female Drosophila model was fed with 10μg/mL PHE.Further research showed that PHE reduced the accumulation of peroxide products and increased the activity of antioxidant enzymes.Then,through antioxidant activity tracking,dimerumic acid(compound 1,the IC_(50) value of 3.4μg/mL on DPPH free radicals scavenging activity),4,5-dihydroxy-3-methoxypentanoic acid(compound 2,new compound),and thymidine(compound 3)were isolated from PHE.It is worth mentioning that dimerumic acid,the major antioxidant compound of PHE(content up to 3%),was discovered in P.hepiali for the first time.It was concluded that PHE showed excellent anti-aging activity at a very low concentration on fat diet-induced high fat Drosophila melanogaster,and dimerumic acid may be its main material basis.These results indicated that PHE had the potential to be developed as antioxidant and anti-aging agent in the healthcare industry. | Akang Dan Yushi Chen Yongqi Tian Shaoyun Wang | 2023 | Food Science and Human Wellness2023，12，4： | 0 |
| 11 | Mitochondrial genome of Chthamalus challengeri(Crustacea:Sessilia): gene order comparison within Chthamalidae and phylogenetic consideration within Balanomorpha显示文摘Acorn barnacles are important model species in researches on intertidal ecology, larval development and biofouling. At present, with the development of mitochondrial genomics, it is helpful to understand the phylogenetic relationship from the mitogenomic level. The complete mitochondrial genome of Chthamalus challengeri was presented. The genome is a circular molecule of 15 358 bp. Compared with other species in Balanomorpha, the non-coding region is longer, while the length of the genes is similar to the other species. The overall A+T content of the mitochondrial genome of C. challengeri is 70.5%. There are variations of initiation and stop codons in the known Balanomorpha mitochondrial genomes. The C. challengeri and C. antennatus within the same genus share the identical gene arrangement. However, the gene arrangement of different genera in Chthamalidae is different, as there is a translocation between two tRNA genes and an inversion involving a large gene block. In particular, both srRNA and lrRNA of the two species in Chthamalus are encoded in the heavy strand, differing from the former Balanomorpha species. The topology and gene arrangement in Chthamalidae support each other. Phylogenetic analysis indicates that the Chthamalidae is monophyletic, while the Balanidae and Archaeobalanidae are polyphyletic. | Panpan Chen Jun Song Xin Shen Yuefeng Cai Ka Hou Chu Yongqi Li Mei Tian | 2019 | Acta Oceanologica Sinica2019，38，6： | 0 |
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