Based on the reconstructed MODIS data and ECMWF reanalysis data from 2003 to 2021,spatial correlations between chlorophyll a(Chl a)and sea surface temperature(SST),photosynthetically available radiation(PAR),aerosol o...Based on the reconstructed MODIS data and ECMWF reanalysis data from 2003 to 2021,spatial correlations between chlorophyll a(Chl a)and sea surface temperature(SST),photosynthetically available radiation(PAR),aerosol optical thickness(AOT),and wind speed(WS)in the Bohai Sea were analyzed from the perspective of time domain and frequency domain.Results indicate that the frequency domain analysis was more conducive to revealing the correlations between Chl a and environmental factors.The spatial pattern of time-domain correlations was similar to the isobaths of the Bohai Sea,which was positive in shallow waters and negative in deep waters for SST,PAR,and AOT,and was reversed for WS.Frequency-domain correlations were obtained by performing Fourier Transform and were higher than correlations in time domain.The spatial distributions indicated that the effects of SST and PAR on Chl a were greater than AOT and WS in the Bohai Sea.Additionally,cross-spectrum analysis was applied to explore the response relationships.A depth-dependent pattern was shown in correlations and time lags,indicating that the influential mechanism of environmental factors on Chl-a concentration is related to seawater depth.展开更多
Chlorophyll-a(Chl-a)concentration is a primary indicator for marine environmental monitoring.The spatio-temporal variations of sea surface Chl-a concentration in the Yellow Sea(YS)and the East China Sea(ECS)in 2001-20...Chlorophyll-a(Chl-a)concentration is a primary indicator for marine environmental monitoring.The spatio-temporal variations of sea surface Chl-a concentration in the Yellow Sea(YS)and the East China Sea(ECS)in 2001-2020 were investigated by reconstructing the MODIS Level 3 products with the data interpolation empirical orthogonal function(DINEOF)method.The reconstructed results by interpolating the combined MODIS daily+8-day datasets were found better than those merely by interpolating daily or 8-day data.Chl-a concentration in the YS and the ECS reached its maximum in spring,with blooms occurring,decreased in summer and autumn,and increased in late autumn and early winter.By performing empirical orthogonal function(EOF)decomposition of the reconstructed data fields and correlation analysis with several potential environmental factors,we found that the sea surface temperature(SST)plays a significant role in the seasonal variation of Chl a,especially during spring and summer.The increase of SST in spring and the upper-layer nutrients mixed up during the last winter might favor the occurrence of spring blooms.The high sea surface temperature(SST)throughout the summer would strengthen the vertical stratification and prevent nutrients supply from deep water,resulting in low surface Chl-a concentrations.The sea surface Chl-a concentration in the YS was found decreased significantly from 2012 to 2020,which was possibly related to the Pacific Decadal Oscillation(PDO).展开更多
Two field studies were conducted to measure pigments in the Southern Yellow Sea (SYS) and the northern East China Sea (NECS) in April (spring) and September (autumn) to evaluate the distribution pattern of phytoplankt...Two field studies were conducted to measure pigments in the Southern Yellow Sea (SYS) and the northern East China Sea (NECS) in April (spring) and September (autumn) to evaluate the distribution pattern of phytoplankton stock (Chl a concentration) and the impact of hydrological features such as water mass,mixing and tidal front on these patterns.The results indicated that the Chl a concentration was 2.43±2.64 (Mean ± SD) mg m-3 in April (range,0.35 to 17.02 mg m-3) and 1.75±3.10 mg m-3 in September (from 0.07 to 36.54 mg m-3) in 2003.Additionally,four areas with higher Chl a concentrations were observed in the surface water in April,while two were observed in September,and these areas were located within or near the point at which different water masses converged (temperature front area).The distribution pattern of Chl a was generally consistent between onshore and offshore stations at different depths in April and September.Specifically,higher Chl a concentrations were observed along the coastal line in September,which consisted of a mixing area and a tidal front area,although the distributional pattern of Chl a concentrations varied along transects in April.The maximum Chl a concentration at each station was observed in the surface and subsurface layer (0-10 m) for onshore stations and the thermocline layer (10-30 m) for offshore stations in September,while the greatest concentrations were generally observed in surface and subsurface water (0-10 m) in April.The formation of the Chl a distributional pattern in the SYS and NECS and its relationship with possible influencing factors is also discussed.Although physical forces had a close relationship with Chl a distribution,more data are required to clearly and comprehensively elucidate the spatial pattern dynamics of Chl a in the SYS and NECS.展开更多
The contraction of isolated rat and rabbit uteri induced by oxytocin and PGF2α was markedly inhibited by chlorpheniramine (Chl) and astemizolum (Ast) , both of which also decreased the resting tension of uteri, and t...The contraction of isolated rat and rabbit uteri induced by oxytocin and PGF2α was markedly inhibited by chlorpheniramine (Chl) and astemizolum (Ast) , both of which also decreased the resting tension of uteri, and their spontaneous contraction. The inhibitory effects of both drugs were dose-dependent. At high concentrations , Chl 7. 4 × 10-4 mol/L and Ast 10-4 mol/L could counteract the contraction of the uteri induced by Oxy and PGF2α, and their spontaneous contraction as well. They decreased the resting tension to the lower level. The mechanism of their non-special relaxed action on uteri could not be completely explained only by their H1-receptor blocking action. Whether they act by blocking calcium channel or by inhibiting calmodulin (CaM) remains to be further explored.展开更多
Aims: Twelve crude extracts were prepared from different parts of Pluchea sagittalis, Cecropia palmata and Brachiaria brizantha, and their effect on the light reaction of photosynthesis. Study Design: Use of fluoresce...Aims: Twelve crude extracts were prepared from different parts of Pluchea sagittalis, Cecropia palmata and Brachiaria brizantha, and their effect on the light reaction of photosynthesis. Study Design: Use of fluorescence of ChL a (Chlorophyll a) to detect inhibitors of photosynthesis in plant extracts. Place and Duration of Study: Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Departamento de Ciências Exatas e da Terra, Universidade Federal de Sao Paulo (UNIFESP), between July 2015 and January 2016. Methodology: The samples had their effect on the light reaction of photosynthesis studied by Chlorophyll a (Chl a) fluorescence transient by the use of chloroplasts isolated from spinach leaves. As negative controls we used the same amounts of DMSO that have been employed to solubilize the samples, and as positive control we have used 10 μM of the commercial herbicide DCMU (Diuron). Results: The extracts inhibited the photosynthesis, and their inhibition sites were located in the range of electron flow from OEC complex and between P<sub>680</sub> to Q<sub>A</sub> of PS II, and inhibited the photosystem II (PS II) by inducing the appearance of the transient bands K and J. Conclusion: Our results suggest an indicative that the photochemical apparatus probably is failing at the donor and acceptor sides of PSII, causing damage to electron transport during the photosynthesis phenomenon.展开更多
Carbon biomass,carbon-to-chlorophyll a ratio(C꞉Chl a),and the growth rate of phytoplankton cells were studied during four seasonal cruises in 2017 and 2018 in Jiaozhou Bay,China.Water samples were collected from 12 st...Carbon biomass,carbon-to-chlorophyll a ratio(C꞉Chl a),and the growth rate of phytoplankton cells were studied during four seasonal cruises in 2017 and 2018 in Jiaozhou Bay,China.Water samples were collected from 12 stations,and phytoplankton carbon biomass(phyto-C)was estimated from microscope-measured cell volumes.The phyto-C ranged from 5.05 to 78.52μg C/L in the bay,and it constituted a mean of 38.16% of the total particulate organic carbon in the bay.High phyto-C values appeared mostly in the northern or northeastern bay.Diatom carbon was predominant during all four cruises.Dinoflagellate carbon contributed much less(<30%)to the total phyto-C,and high values appeared often in the outer bay.The C꞉Chl a of phytoplankton cells varied from 11.50 to 61.45(mean 31.66),and high values appeared in the outer bay during all four seasons.The phyto-C was also used to calculate the intrinsic growth rates of phytoplankton cells in the bay,and phytoplankton growth rates ranged from 0.56 to 1.96/d;the rate was highest in summer(mean 1.79/d),followed by that in fall(mean 1.24/d)and spring(mean 1.17/d),and the rate was lowest in winter(mean 0.77/d).Temperature and silicate concentration were found to be the determining factors of phytoplankton growth rates in the bay.To our knowledge,this study is the first report on phytoplankton carbon biomass and C꞉Chl a based on water samples in Jiaozhou Bay,and it will provide useful information for studies on carbon-based food web calculations and carbon-based ecosystem models in the bay.展开更多
With specific designed prmers. CYP2B6 and CYP1A1 cDNA were generatecl by reverse transcrlI7tion-Polymerase chain reaction(RT-PCR )technlque Performed on total RNAs isolated frorn hum1ln liver and 3-rnethylch(,lanthren...With specific designed prmers. CYP2B6 and CYP1A1 cDNA were generatecl by reverse transcrlI7tion-Polymerase chain reaction(RT-PCR )technlque Performed on total RNAs isolated frorn hum1ln liver and 3-rnethylch(,lanthrene(3-Mtt)induc human amnion FL, cells. Cell llnes (CHL, 2B6 and CtHL-1A1 ) capableof expressing hunlan cytochome P 15O (CYP ) 2B6 and 1A1 were establishecl after transfection of corre-sponding eukaryotic reconlbinant expression plasmid with human CYP2ll6 and 1A1 cDNA lnserts respectlvely. These cell lines stably expressed the mRNAs and the enzymatic activltles cc)rresI’onding to ttYP2B6and CYP1A1, respectively’ Compared with Chinese hamster lung (CHL) cells, the n1icr()nucleus frecluencyin CHl,-2B6 cells is markedly lncreased when exPosed to nitrosamines,aflatoxln B, (AFB1) and cyclophos-Phamide (CPA). Thls is also in CHL-1A1 cells,when exposed to carcinogenic polycycllc aromatic hydrocar-bons.展开更多
基金Supported by the Key Research and Development Program of 14 th Five year Plan of China(No.2021YFC3200401-04)the Major Scientific and Technological Projects of Tianjin(No.18 ZXRHSF00270)。
文摘Based on the reconstructed MODIS data and ECMWF reanalysis data from 2003 to 2021,spatial correlations between chlorophyll a(Chl a)and sea surface temperature(SST),photosynthetically available radiation(PAR),aerosol optical thickness(AOT),and wind speed(WS)in the Bohai Sea were analyzed from the perspective of time domain and frequency domain.Results indicate that the frequency domain analysis was more conducive to revealing the correlations between Chl a and environmental factors.The spatial pattern of time-domain correlations was similar to the isobaths of the Bohai Sea,which was positive in shallow waters and negative in deep waters for SST,PAR,and AOT,and was reversed for WS.Frequency-domain correlations were obtained by performing Fourier Transform and were higher than correlations in time domain.The spatial distributions indicated that the effects of SST and PAR on Chl a were greater than AOT and WS in the Bohai Sea.Additionally,cross-spectrum analysis was applied to explore the response relationships.A depth-dependent pattern was shown in correlations and time lags,indicating that the influential mechanism of environmental factors on Chl-a concentration is related to seawater depth.
基金Supported by the Fundamental Research Funds for the Central Universities(Nos.202341017,202313024)。
文摘Chlorophyll-a(Chl-a)concentration is a primary indicator for marine environmental monitoring.The spatio-temporal variations of sea surface Chl-a concentration in the Yellow Sea(YS)and the East China Sea(ECS)in 2001-2020 were investigated by reconstructing the MODIS Level 3 products with the data interpolation empirical orthogonal function(DINEOF)method.The reconstructed results by interpolating the combined MODIS daily+8-day datasets were found better than those merely by interpolating daily or 8-day data.Chl-a concentration in the YS and the ECS reached its maximum in spring,with blooms occurring,decreased in summer and autumn,and increased in late autumn and early winter.By performing empirical orthogonal function(EOF)decomposition of the reconstructed data fields and correlation analysis with several potential environmental factors,we found that the sea surface temperature(SST)plays a significant role in the seasonal variation of Chl a,especially during spring and summer.The increase of SST in spring and the upper-layer nutrients mixed up during the last winter might favor the occurrence of spring blooms.The high sea surface temperature(SST)throughout the summer would strengthen the vertical stratification and prevent nutrients supply from deep water,resulting in low surface Chl-a concentrations.The sea surface Chl-a concentration in the YS was found decreased significantly from 2012 to 2020,which was possibly related to the Pacific Decadal Oscillation(PDO).
基金Supported by the National Natural Science Foundation of China (No.40606036)the National High Technology Research and Development Program (863 Program) (No.200lAA6360l0)the National Basic Research Program of China (973 Program) (No.2006CB400606)
文摘Two field studies were conducted to measure pigments in the Southern Yellow Sea (SYS) and the northern East China Sea (NECS) in April (spring) and September (autumn) to evaluate the distribution pattern of phytoplankton stock (Chl a concentration) and the impact of hydrological features such as water mass,mixing and tidal front on these patterns.The results indicated that the Chl a concentration was 2.43±2.64 (Mean ± SD) mg m-3 in April (range,0.35 to 17.02 mg m-3) and 1.75±3.10 mg m-3 in September (from 0.07 to 36.54 mg m-3) in 2003.Additionally,four areas with higher Chl a concentrations were observed in the surface water in April,while two were observed in September,and these areas were located within or near the point at which different water masses converged (temperature front area).The distribution pattern of Chl a was generally consistent between onshore and offshore stations at different depths in April and September.Specifically,higher Chl a concentrations were observed along the coastal line in September,which consisted of a mixing area and a tidal front area,although the distributional pattern of Chl a concentrations varied along transects in April.The maximum Chl a concentration at each station was observed in the surface and subsurface layer (0-10 m) for onshore stations and the thermocline layer (10-30 m) for offshore stations in September,while the greatest concentrations were generally observed in surface and subsurface water (0-10 m) in April.The formation of the Chl a distributional pattern in the SYS and NECS and its relationship with possible influencing factors is also discussed.Although physical forces had a close relationship with Chl a distribution,more data are required to clearly and comprehensively elucidate the spatial pattern dynamics of Chl a in the SYS and NECS.
文摘The contraction of isolated rat and rabbit uteri induced by oxytocin and PGF2α was markedly inhibited by chlorpheniramine (Chl) and astemizolum (Ast) , both of which also decreased the resting tension of uteri, and their spontaneous contraction. The inhibitory effects of both drugs were dose-dependent. At high concentrations , Chl 7. 4 × 10-4 mol/L and Ast 10-4 mol/L could counteract the contraction of the uteri induced by Oxy and PGF2α, and their spontaneous contraction as well. They decreased the resting tension to the lower level. The mechanism of their non-special relaxed action on uteri could not be completely explained only by their H1-receptor blocking action. Whether they act by blocking calcium channel or by inhibiting calmodulin (CaM) remains to be further explored.
文摘Aims: Twelve crude extracts were prepared from different parts of Pluchea sagittalis, Cecropia palmata and Brachiaria brizantha, and their effect on the light reaction of photosynthesis. Study Design: Use of fluorescence of ChL a (Chlorophyll a) to detect inhibitors of photosynthesis in plant extracts. Place and Duration of Study: Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Departamento de Ciências Exatas e da Terra, Universidade Federal de Sao Paulo (UNIFESP), between July 2015 and January 2016. Methodology: The samples had their effect on the light reaction of photosynthesis studied by Chlorophyll a (Chl a) fluorescence transient by the use of chloroplasts isolated from spinach leaves. As negative controls we used the same amounts of DMSO that have been employed to solubilize the samples, and as positive control we have used 10 μM of the commercial herbicide DCMU (Diuron). Results: The extracts inhibited the photosynthesis, and their inhibition sites were located in the range of electron flow from OEC complex and between P<sub>680</sub> to Q<sub>A</sub> of PS II, and inhibited the photosystem II (PS II) by inducing the appearance of the transient bands K and J. Conclusion: Our results suggest an indicative that the photochemical apparatus probably is failing at the donor and acceptor sides of PSII, causing damage to electron transport during the photosynthesis phenomenon.
基金Supported by the National Natural Science Foundation of China(Nos.31700425,91751202)the External Cooperation Program of Chinese Academy of Sciences(No.133137KYSB20200002)the Taishan Scholars Project to Song SUN。
文摘Carbon biomass,carbon-to-chlorophyll a ratio(C꞉Chl a),and the growth rate of phytoplankton cells were studied during four seasonal cruises in 2017 and 2018 in Jiaozhou Bay,China.Water samples were collected from 12 stations,and phytoplankton carbon biomass(phyto-C)was estimated from microscope-measured cell volumes.The phyto-C ranged from 5.05 to 78.52μg C/L in the bay,and it constituted a mean of 38.16% of the total particulate organic carbon in the bay.High phyto-C values appeared mostly in the northern or northeastern bay.Diatom carbon was predominant during all four cruises.Dinoflagellate carbon contributed much less(<30%)to the total phyto-C,and high values appeared often in the outer bay.The C꞉Chl a of phytoplankton cells varied from 11.50 to 61.45(mean 31.66),and high values appeared in the outer bay during all four seasons.The phyto-C was also used to calculate the intrinsic growth rates of phytoplankton cells in the bay,and phytoplankton growth rates ranged from 0.56 to 1.96/d;the rate was highest in summer(mean 1.79/d),followed by that in fall(mean 1.24/d)and spring(mean 1.17/d),and the rate was lowest in winter(mean 0.77/d).Temperature and silicate concentration were found to be the determining factors of phytoplankton growth rates in the bay.To our knowledge,this study is the first report on phytoplankton carbon biomass and C꞉Chl a based on water samples in Jiaozhou Bay,and it will provide useful information for studies on carbon-based food web calculations and carbon-based ecosystem models in the bay.
文摘With specific designed prmers. CYP2B6 and CYP1A1 cDNA were generatecl by reverse transcrlI7tion-Polymerase chain reaction(RT-PCR )technlque Performed on total RNAs isolated frorn hum1ln liver and 3-rnethylch(,lanthrene(3-Mtt)induc human amnion FL, cells. Cell llnes (CHL, 2B6 and CtHL-1A1 ) capableof expressing hunlan cytochome P 15O (CYP ) 2B6 and 1A1 were establishecl after transfection of corre-sponding eukaryotic reconlbinant expression plasmid with human CYP2ll6 and 1A1 cDNA lnserts respectlvely. These cell lines stably expressed the mRNAs and the enzymatic activltles cc)rresI’onding to ttYP2B6and CYP1A1, respectively’ Compared with Chinese hamster lung (CHL) cells, the n1icr()nucleus frecluencyin CHl,-2B6 cells is markedly lncreased when exPosed to nitrosamines,aflatoxln B, (AFB1) and cyclophos-Phamide (CPA). Thls is also in CHL-1A1 cells,when exposed to carcinogenic polycycllc aromatic hydrocar-bons.
