Spatial correlations in time and frequency domains between chlorophyll-a concentration and environmental factors in the Bohai Sea

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.

Spatio-temporal variability of surface chlorophyll a in the Yellow Sea and the East China Sea based on reconstructions of satellite data of 2001-2020

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).

乌头类中药对CHL细胞的DNA损伤作用

[目的]观察乌头类中药盐附子和乌头碱对CHL细胞(中国仓鼠肺成纤维细胞)的DNA损伤作用。[方法]采用单细胞凝胶电泳法检测盐附子、乌头碱对CHL细胞DNA即刻损伤的影响。在加和不加S9时,盐附子均设5个剂量组(终浓度分别为5、2.5、1.25、0.625、0.313 mg生药∕ml)、乌头碱设4个剂量组(终浓度分别为100、50、25、5μg/ml),试验同时设PBS阴性对照组和阳性对照组,阳性对照在不加S9时为0.1 mmol/ml重铬酸钾,加S9时为80μg/ml环磷酰胺。[结果]在加和不加S9时,盐附子各浓度组拖尾细胞率和拖尾细胞尾长与阴性对照比较差异无统计学意义(P﹥0.05),乌头碱100μg/ml和50μg/ml组拖尾细胞率和拖尾细胞尾长与阴性对照之间差异有统计学意义(P﹤0.05),乌头碱各浓度组拖尾细胞率和拖尾细胞尾长存在剂量反应关系。[结论]在本试验条件下,加与不加S9时,乌头碱浓度为100μg/ml和50μg/ml时对CHL细胞有DNA损伤作用;盐附子5、2.5、1.25、0.625、0.313 mg生药/ml时未观察到对CHL细胞有DNA损伤作用。

滇池Chl a与水质及气象指标的偏相关分析

基于1999-2010年滇池8个监测点的每月一次的水温、p H、透明度、溶解氧、高锰酸钾指数、BOD、铵氮、总磷、总氮等9个理化指标;以及水质观测同日的滇池大观楼气象站的日最高气温、日最低气温、日平均气温、日照时数、平均风速、日最大风速、日最大风速的风向等7个气象指标,采用SPSS软件对同日叶绿素a浓度进行偏相关分析,并根据偏相关分析的结果,分别对各监测点的显著相关因子进行回归分析,以明确各指标对Chl a的相关显著性和贡献程度。结果显示,9个水质指标中,在各观测点均与Chl a具有显著相关性的为p H、BOD、总氮或总磷,在部分观测点溶解氧、水温、高锰酸钾指数也与Chl a显著相关;相对于水质指标而言,7个气象指标基本上对Chla的影响不明显。

低剂量亚硝酸钠诱导CHL细胞DNA损伤的适应性反应

目的:研究低剂量亚硝酸钠(NaNO2)诱导CHL细胞DNA损伤的适应性反应及其形成机制。方法:采用单细胞凝胶电泳试验检测DNA的损伤程度。分别以浓度为0.01mg/L、0.1mg/L和1mg/L的NaNO2预处理CHL细胞6h后,观察细胞对随后的1g/L冲击剂量NaNO2的适应性反应;用3-氨基苯甲酰胺(3-AB)分别在低剂量预处理前和预处理6h后抑制聚ADP核糖聚合酶(PARP-1)的活性,观察其对适应性反应的阻断情况。结果:未经低剂量预处理的细胞,接触1g/L的NaNO218h后,DNA损伤较严重,其细胞拖尾率为7.87%,明显高于正常对照组(P<0.01);浓度为0.01mg/L和0.1mg/L的NaNO2预处理CHL细胞后,可明显缓解1g/L冲击剂量的NaNO2对CHL细胞DNA的损伤作用,其细胞拖尾率分别为3.55%和1.06%,明显低于未经低剂量NaNO2预处理组细胞的拖尾率(P<0.05;P<0.01);而经1mg/L的NaNO2预处理的细胞,接触1g/L的NaNO218h后,DNA损伤较严重,其细胞拖尾率为6.09%,与未经低剂量NaNO2预处理组细胞的拖尾率相比,差异无显著(P>0.05)。距离指标及复合指标也有相同趋势。在低剂量NaNO2预处理细胞前采用3AB抑制PARP-1活性可阻断适应性反应的产生;而在低剂量NaNO2预处理细胞6h后再用3AB抑制PARP-1活性,则不会阻断适应性反应的产生。结论:浓度等于或低于0.1mg/L的NaNO2可通过激活PARP-1诱导CHL细胞DNA损伤的适应性反应,而且,能诱导适应性反应的剂量很可能对机体DNA不造成损伤。

CYP2B6cDNA导入V79、FL和CHL细胞中稳定表达及其初步鉴定

ＣＹＰ２Ｂ６ｃＤＮＡ导入Ｖ７９、ＦＬ和ＣＨＬ细胞中稳定表达及其初步鉴定吴健敏，董海涛，余应年，朱丽君（浙江医科大学病理生理学教研室及医学分子生物学实验室杭州３１００３１）细胞色素Ｐ４５０是代谢活化大多数前致突变物／致癌物的主要酶系，在建株细胞中这些基...

褪黑激素对CHL细胞过氧化DNA断裂的防护作用

ＤＮＡ氧化性损伤同衰老及许多年龄相关疾病（肿瘤，心血管疾病）关系密切［１］。据报道，褪黑激素（Ｍｅｌａｔｏｎｉｎ，ＭＴ）参与哺乳类细胞许多重要的生理病理过程的调节，如矫正生物钟紊乱，增强免疫，抗氧化作用等［２］。ＤＮＡ链断裂是常见的过氧化损伤类型，为...

VIDAS CHL诊断法检测男性尿液中沙眼衣原体试验研究

[目的]为研究能否用全自动快速免疫(VIDASCHL)诊断法检测尿液中沙眼衣原体(CT)。[方法]采用VIDASCHL检测262例男性患者尿道拭子及尿液沉渣中CT抗原。[结果]与扩大金标准相比,VIDASCHL检测尿道拭子、尿沉渣敏感性分别为89.09%(P﹥0.05)、81.82%(P﹥0.05);特异性均为99.52%(P﹥0.05)。[结论]VI-DASCHL诊断法检测男性尿液中的沙眼衣原体具有高度敏感性和特异性。

转入人细胞色素P450-3A4基因的CHL细胞可代谢活化异环磷酰胺

环境污染物的致癌、致突变效应以及肿瘤化疗诱发第二肿瘤的风险是人们普遍关注的问题。大多数化学致癌物本身不具活性，必须在体内经过代谢活化才能诱发肿瘤。细胞色素Ｐ４５０（ＣＹＰ）同功酶系在外来化合物的代谢活化中起主要作用，可是目前用于遗传毒理学研究的建株细...

Distribution patterns of chlorophyll a in spring and autumn in association with hydrological features in the southern Yellow Sea and northern East China Sea

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.

Enzymatic activity and chlorophyll fluorescence imaging of maize seedlings (Zea mays L.) after exposure to low doses of chlorsulfuron and cadmium

The aim of this research was to study the influence of chlorsulfuron residue and cadmium on the enzymatic activity and photosynthetic apparatus of maize(Zea mays L.) plants. Chlorsulfuron and cadmium at 0.001 and 5.0 mg kg–1, respectively, were mixed and applied to soil prior to planting. The levels of chlorsulfuron-and cadmium-induced stress to plants were estimated by growth, chlorophyll content, lipid peroxide content, enzyme activities, and major fluorescence parameters of chlorophyll(revealed by the fluorescence imaging system Fluor Cam). Chlorsulfuron negatively affected the chlorophyll content, photochemical efficiency of photosystem II in the dark-adapted state, the maximum efficiency of photosystem II, photochemical quenching coefficient, and steady-state fluorescence decline ratio in the leaves of maize seedlings. However, cadmium did not produce noticeable changes. Plants that were exposed to both chlorsulfuron and cadmium showed an obvious increase in the steady-state fluorescence decline ratio. These results implied that the seedlings possessed more resistance to cadmium than to chlorsulfuron and their resistance to chlorsulfuron toxicity was enhanced by the presence of cadmium. The results also suggested that chlorophyll fluorescence imaging reveals overall alterations within the leaves but may not reflect small-scale effects on tissues, as numeric values of specific parameters are averages of the data collected from the whole leaf.

Carbon biomass,carbon-to-chlorophyll a ratio and the growth rate of phytoplankton in Jiaozhou Bay,China

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.

Quantification of the impact of environmental factors on chlorophyll in the open ocean

Many previous studies of the impact of oceanic environmental factors on chlorophyll(CHL)in a specific region focused on sea surface temperature(SST),mixed-layer depth(MLD),or wind stress(WS)alone.In this study,relationship between CHL and all those environmental factors(SST,MLD,and WS)in the open ocean was quantified for five regions within the subtropical gyres and the variation trend of 13-year(2003–2015)was analyzed using satellite observations and Argo measurements.The correlation analysis results show that MLD was correlated positively with CHL,SST was correlated negatively with CHL,and the correlation between CHL and WS was either positive or negative.Based on the significance of the correlations,models representing the relationships were established using the multiple linear regression and analyzed,showing that the environmental factors were the major determinants of CHL change.The regression coefficients show that both SST and MLD have remarkable effect on CHL.Our derived models could be used to diagnose the past changes,understand present variability,and predict the future state of CHL changes based on environmental factors,and help us understand the dynamics of CHL variation in the open ocean.

CHL细胞DNA解螺旋荧光分析法实验参数的选择及其应用

为确定ＣＨＬ细胞为测试靶细胞时ＦＡＤＵ的较佳实验参数，采用变化解旋温度及解旋液碱浓度，并根据Ｂｉｒｎｂｏｉｍ等的判断标准，结果表明解旋温度先０℃３０ｍｉｎ后１５℃６０ｍｉｎ；解旋液ＮａＯＨ浓度０４Ｎ效果较佳。并以此为条件把该法应用于检测过氧化氢（Ｈ２Ｏ２）诱导的ＤＮＡ过氧化损伤－适应及抗过氧化作用。

Inhibitory Effects of Chlorpheniramine and Astemizolum on Contraction of Isolated Rat and Rabbit Uteri Induced by Oxytocin and PGF_(2α)

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.

欧洲高血压学会一中国高血压联盟关于脑卒中患者最佳血压控制目标研究（ESH—CHL—SHOTtrial）方案简介（二）

随机序号由统计中心产生。当患者的信息输入电子化临床研究表格（eCRF）时，将会自动获得一个随机序号。

欧洲高血压学会一中国高血压联盟关于脑卒中患者最佳血压控制目标研究（ESH—CHL—SHOTtrial）方案简介（一）

脑卒中不仅是全世界最主要的致死病因之一，由于脑卒中幸存者的活动及认知能力严重损伤，它也是全球最主要的疾病负担。特别在远东与南欧人群中，脑卒中的发病率高于冠心病及其他循环系疾病，在人群中造成的健康寿命损害及医疗服务与社会经济负担较其他疾病更为严重。

Fluorescence of Chlorophyll a for Discovering Inhibitors of Photosynthesis in Plant Extracts

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 P680 to QA 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.