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1Nutrient concentrations and fluxes in the Changjiang Estuary during summer显示文摘In June 2003 and 2006 concentrations of nutrient were determined in the Changjiang Estuary.The data indicated that phosphate and nitrate did not behave conservatively in the estuary,but silicate behaved conservatively.An important mobilization of phosphate and nitrate was observed from the river up to halfway in the estuary.Both input flux(from river to estuary) and output flux(from estuary to coastal zone) of phosphate,silicate and nitrate were calculated from statistical interpretations of the salinity profiles.There was a large discrepancy between input and output fluxes of phosphate and nitrate.The river fluxes of silicate,phosphate and nitrate(f r ) are augmented 5.3%,28.9% and 36.6% in June 2003 and 1.0%,62.5%,31.7% in June 2006 by internal inputs(f i ).The phosphate and nitrate fluxes are enhanced through the estuarine process,while silicate flux is unaltered.The authors present some long-term data for nutrient concentrations and the ratios of silicon to nitrogen to phosphorus in the Changjiang Estuary.Silicate level falled in the last two decades,while concentration of nitrate increased.Phosphate concentration had no significant change.CHEN Hongtao YU Zhigang YAO Qingzheng MI Tiezhu LIU Pengxia 2010Acta Oceanologica Sinica2010,29,2:13
2Climatology and seasonal variability of satellite-derived chlorophyll a around the Shandong Peninsula显示文摘The chlorophyll a(Chl a)is an important indicator of marine ecosystems.The spatiotemporal variation of the Chl a greatly aff ects the mariculture and marine ranching in coastal waters of the Shandong Peninsula.In the current study,the climatology and seasonal variability of surface Chl-a concentration around the Shandong Peninsula are investigated based on 16 years(December 2002-November 2018)of satellite observations.The results indicate that the annual mean Chl-a concentration is greater in the Bohai Sea than in the Yellow Sea and decreases from coastal waters to off shore waters.The highest Chl-a concentrations are found in Laizhou Bay(4.2-8.0 mg/m^(3)),Haizhou Bay(4.2-5.9 mg/m^(3))and the northeast coast of the Shandong Peninsula(4.4-5.0 mg/m^(3)),resulting from the combined eff ects of the intense riverine input and long residence time caused by the concave shape of the coastline.The seasonal Chl-a concentration shows a significant spatial variation.The Chl-a concentrations in these three subregions generally exhibit an annual maximum in August/September,due to the combined eff ects of sea surface temperature,river discharge and sea surface wind.In the southeast coast region,however,the Chl-a concentration is lowest throughout the year and reaches a maximum in February with a minimum in July,forced by the seasonal evolution of the Yellow Sea Cold Water and monsoon winds.The interannual Chl-a concentration trends vary among regions and seasons.There are significant increasing trends over a large area around Haizhou Bay from winter to summer,which are mainly caused by the rising sea surface temperature and eutrophication.In other coastal areas,the Chl-a concentration shows decreasing trends,which are clearest in summer and induced by the weakening land rainfall.This study highlights the differences in the Chl-a dynamics among regions around the Shandong Peninsula and is helpful for further studies of coupled physical-ecological-human interactions at multiple scales.Xiukai SONG Yanzhen GU Fangguo ZHAI Peiliang LI Pengxia LIU Zizhou LIU Wenfan WU Yaozu CHEN Xiangyang JIANG Jianlong HE 2021Journal of Oceanology and Limnology2021,39,4:3
3Therapeutic Effect of Human Umbilical Cord Multipotent Mesenchymal Stromal Cells in a Rat Model of Stroke显示文摘Wenbin Liao Jiang Xie Jian Zhong Yongjun Liu Lei Du Bin Zhou Jie Xu Pengxia Liu Shaoguang Yang Jiming Wang Zhibo Han Zhong Chao Han 2009Transplantation2009,,3:2
4A high sensitivity localized surface plasmon resonance sensor based on D-shaped photonic crystal fiber for low refractive index detection显示文摘In this paper,a localized surface plasmon resonance(LSPR)refractive index sensor based on photonic crystal fiber(PCF)is proposed to solve the problem of low refractive index analyte detection.31 silver nanowires are placed on the surface of the D-shaped PCF,which increases the contact area between the plasma material and the analyte.The simulation results indicate that the maximum sensitivity of the sensor reaches 16400 nm/RIU,and the refractive index detection range is 1.26—1.33.It is proved that the sensor has a good prospect in low refractive index detection.PAN Honggang CAO Chuanbo ZHANG Ailing PAN Fei SUI Pengxia LIU Xinbo 2022Optoelectronics Letters2022,18,7:2
5Endothelial progenitor cell therapy in atherosclerosis: A double-edged sword?显示文摘Pengxia Liu Bin Zhou Dongsheng Gu Lei Zhang Zhongchao Han 2008Ageing Research Reviews2008,,2:1
6A Parallel ATPG Algorithm Based on Big Function Block显示文摘The paper presents a parallel ATPG algorithm - PTGBP, which aims at decreasing the complexity of the ATPG by partitioning circuit under test (CUT) to big function blocks (BFB) and processing them parallelly. PTGBP adopts hybrid circuit mode and hybrid fault model, and organizes the parallel course in term of master/slave mode. Master processor loads the whole netlist of CUT based on BFB, every slave processor loads logic level (gate/function block/basic logic units) netlist of a BFB. Test generation (TG) uses BFB input/output s-a-0/s-a-1 fault model; fault simulation uses logic level single stuck fault model. Master controls the PTGBP’s running course and ensures the correctness of its running result; slaves provide the results of fault sensitization compatible computation and fault simulation to master parallelly. PTGBP algorithm is under implementation.Zhide Zeng Pengxia Liu 2000湖南大学学报(自然科学版)2000,27,S2:1
7Submarine groundwater discharge and seasonal hypoxia off the Changjiang River Estuary显示文摘Hypoxia is a common phenomenon in the sea adjacent to the Changjiang River Estuary(CJE),one of the global major estuaries.Submarine groundwater discharge(SGD)is a widely recognized pathway for terrestrial materials entering the sea,and has been found to be significant off the CJE.We used a^(222)Rn mass balance model to estimate the SGD fluxes off the CJE and showed that it is linked to seasonal dissolved oxygen(DO)variations.Average SGD fluxes were estimated to be(0.012±0.010)m^(3)/(m^(2)·d)in winter,(0.034±0.015)m^(3)/(m^(2)·d)in summer,and(0.020±0.010)m^(3)/(m^(2)·d)in autumn.We found a significant negative correlation between DO concentrations and SGD rates with groundwater discharge being highest in the summer flood season.In addition,distribution patterns of SGD and hypoxia zones in summer are spatially overlapped,indicating that SGD is an important contributor to summer hypoxia in this region.Tianyi Zhu Bochao Xu Xiaoyi Guo Qinsheng Wei Ergang Lian Pengxia Liu William C.Burnett Qingzhen Yao Zhigang Yu 2023Acta Oceanologica Sinica2023,42,8:0
8Optimization of Shanghai Marine Environmental Monitoring Sites in the Identification of Boundaries of Different Water Quality Grades显示文摘Water quality is critical to ensure that marine resources and the environment are utilized in a sustainable manner. The objective of this study is therefore to investigate the optimum placement of marine environmental monitoring sites to monitor water quality in Shanghai, China. To improve the mapping or estimation accuracy of the areas with different water quality grades, the monitoring sites were fixed in transition bands between areas of different grades rather than in other positions. Following bidirectional optimization method, first, 18 candidate sites were selected by filtering out specific site categories. Second, three of these were, in turn, eliminated because of the rule defined by the changes in the areas of water quality grades and by the standard deviation of the interpolation errors of dissolved inorganic nitrogen(DIN) and phosphate(PO_4-P). Furthermore, indicator kriging was employed to depict the transition bands between different water quality grades whenever new sampling sites were added. The four optimization projects of the newly added sites reveal that, all optimized sites were distributed in the transition bands of different water grades, and at the same time in the areas where the historical sites were sparsely distributed. New sites were also found in the overlap region of different transition bands. Additional sites were especially required in these regions to discriminate the boundaries of different water quality grades. Using the bidirectional optimization method of the monitoring sites, the boundaries of different water quality grades could be determined with a higher precision. As a result, the interpolation errors of DIN and PO_4-P could theoretically decrease.FAN Haimei GAO Bingbo WANG Jinfeng QIN Xiaoguang LIU Pengxia HU Maogui XU Peng 2018Journal of Ocean University of China2018,17,4:0
9Spatiotemporal variations in the organic carbon accumulation rate in mangrove sediments from the Yingluo Bay,China,since 1900显示文摘Mangroves can not only provide multiple ecosystem service functions,but are also efficient carbon producers,capturers,and sinks.The estimation of the organic carbon accumulation rate(OCAR)in mangrove sediments is fundamental for elucidating the role of mangroves in the global carbon budget.In particular,understanding the past changes in the OCAR in mangrove sediments is vital for predicting the future role of mangroves in the rapidly changing environment.In this study,three dated sediment cores from interior and fringe of mangroves in the Yingluo Bay,China,were used to reconstruct the spatiotemporal variations of the calculated OCAR since 1900 in this area.The increasing OCAR in the mangrove interior was attributed to mangrove flourishment induced by climate change characterized by the rising temperature.However,in the mangrove fringe,the strengthening hydrodynamic conditions under the sea level rise were responsible for the decreasing OCAR,particularly after the1940 s.Furthermore,the duration of inundation by seawater was the primary factors controlling the spatial variability of the OCAR from the mangrove fringe to interior,while the strengthened hydrodynamic conditions after the 1940 s broke this original pattern.Yao Zhang Xianwei Meng PengXia Jun Zhang Dahai Liu Zhen Li Wanzhu Wang 2021Acta Oceanologica Sinica2021,40,8:0
10Melatonin delays leaf senescence in pak choi(Brassica rapa subsp.chinensis)by regulating biosynthesis of the second messenger cGMP显示文摘Melatonin(MT)is a low molecular weight compound with multiple biological functions in plants.It is known to delay leaf senescence in various species.However,no data are available on the MT signaling pathway in postharvest vegetables.This study demonstrates that MT increases cGMP concentration and the expression of the cGMP synthesis gene BcGC1 in pak choi.The c GMP inhibitor LY83583 destroys effect of MT delaying the leaf senescence.LY83583 also prevents MT treatment from reducing the expression of chlorophyll metabolism-related genes(BcNYC1,BcNOL,BcPPH1/2,BcSGR1/2,and BcPAO)and senescence genes(BcSAG12 and BcSAG21).It also inhibits MT from reducing the activity of the key chlorophyll catabolism enzymes Mg-dechelatase,pheophytinase,and pheide a oxygenase.Thus,the ability of MT to maintain high levels of chlorophyll metabolites is also destroyed.The Arabidopsis c GMP synthetic gene mutant atgc1 was used to confirm that delayed leaf senescence caused by MT is mediated,at least in part,by the second messenger c GMP.Xuesong Liu Ronghui An Guofeng Li Shufen Luo Huali Hu Pengxia Li 2024Horticultural Plant Journal2024,10,1:0
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