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Effects of e-e Interaction on the CDW of MX Complex

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Chinese Physics Letters 1994年第2期11卷 105-108页

作者： yu zhigang SUN Xin Department of Physics Fudan UniversityShanghai 200433

We have considered the effects of Hubbard repulsion on the charge-density-wave(CDW)state of halogen-bridged mixed-valence transition metal complex(MX complex)within mean field theory(MFT),and taken electron correlation into account by second-order perturbation relative to the mean field *** is seen correlation reduces the dimerization and narrows the band gap further compared with MFT.

关键词： state. narrow perturbation

Estimation of growth rate of Skeletonema costatum based on relative expression amount of PCNA gene

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Acta Oceanologica Sinica 2008年第6期27卷 149-158页

作者： HE Shanying yu zhigang College of Environmental Science and Engineering Zhejiang Gongshang University Hangzhou 310012 China College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266003 China

Partial sequence of Skeletonema costatum proliferating cell nuclear antigen （PCNA） gene was obtained by reverse transcriptase PCR（RT-PCR） and 3＇ rapid amplification of cDNA ends （3＇-RACE） techniques. Based on the obtained PCNA and cytochrome b gene（ Cyt b gene） sequences, a real-time fluorescent quantitative PCR （FQ-PCR） method was developed to detect the expression S. costatum PCNA gene, and this method was applied to study the relationship between the growth rate of S. costatum and the average expression amount of PCNA gene in a single cell. The expression amount of PCNA gene had large variation in cells collected at different culture phases, and the trend was well consistent with the growth rate, which suggested that the expression amount of PCNA gene correlated well with the cell division, and the PCNA could be a promising indicator for the S. costatum cell proliferation. Furthermore, using the PCNA gene as the objective gene and the Cyt b gene as the house-keeping gene, a new method for estimating the in situ growth rate of S. costatum was established by analysis of the relative expression quantity （REQ） of the PCNA gene.

关键词： Skeletonema costatum fluorescent quantitative PCR PCNA growth rate

Development of a real-time PCR method for Thalassiosira rotula rapid detection

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Acta Oceanologica Sinica 2007年第2期26卷 133-139页

作者： HE Shanying yu zhigang MI Tiezhu College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266003 China College of Environmental Science and Engineering Ocean University of China Qingdao 266003 China

Gene specific primers and DNA probe were designed based on the sequence of 18S rDNA cloned from the red tide alga Thalassiosira rotula. A real-time fluorescent quantitative PCR （RFQ - PCR） method was developed for quantitative detection of T. rotula. The RFQ - PCR assay data showed that the results obtained with the RFQ - PCR quite good agreement with those with the light microscope （LM） counting method, which suggested that the RFQ - PCR could be a useful method for red tide alga detection.

关键词： red tide Thalassiosira rotula fluorescent quantitative PCR 18S rDNA

Pigment signatures of some diatoms isolated from China seas

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Acta Oceanologica Sinica 2006年第1期25卷 108-118页

作者： YAO Peng yu zhigang DENG Chunmei College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266003 China

The photosynthetic pigments of 12 species （14 strains） of cultured diatoms from six genera under specific conditions were examined by the HPLC. The diatom genera were Skeletonema, Thalassiosira, Chaetoceros, Nitzschla, Phaeodactylum and Meuniera. All strains were isolated from China seas and most of them were from the Jiaozhou Bay, China. Fifteen pigments were identified and eight of them were various chlorophyll a derivatives. Chlorophyll a, c2 and c1 and the carotenoids fucoxanthin, diadinoxanthin, diatoxanthin and β, β-carotene existed in all species. The ratios of each pigment to chlorophyll a were compared with the results in literatures. The pigment ratios of this study generally fall within the ranges reported by the literatures although the maximum ratio of fucoxanthin to chlorophyll a was higher and the ratios of chlorophyll c and diatoxanthin to chlorophyll a were low. The pigment ratios are useful to understanding the pigment signatures of diatoms in the Jiaozhou Bay, China, and to setting up the chemotaxonomic method of phytoplankton in these sea areas.

关键词： diatoms pigment HPLC ratio Jiaozhou Bay

Photoinduced Ultrafast Process of Relaxation in Polymer

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Chinese Physics Letters 1993年第9期10卷 550-553页

作者： yu zhigang HUANG Qingfeng SUN Xin Natiomil Laboratory of Infra.red Physics Shanghai Institute of Technical PhysicsShanghai 200083 Department of Physics Fudtm UniversityShanghai 200433

On the basis of multi-phonon transition theory,the origin of the fust component(100fs)and the slow component(ns)in photoexcitiition dynfmiics is explained and their evolution time is *** these results,it is seen that the fast component is due to the formation from freii electron-hole pair to neutral bipolaron, and the slow one is due to the non-radiative decay of bipoltiron.

关键词： neutral decay radiative

Development of a Real-Time PCR Method (Taqman) for Rapid Identification and Quantification of Prorocentrum donghaiense

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Journal of Ocean University of China 2012年第3期11卷 366-374页

作者： yuAN Jian MI Tiezhu ZHEN yu yu zhigang College of Marine Life Sciences Ocean University of ChinaQingdao 266003P.R.China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100P.R.China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100P.R.China Key Laboratory of Marine Environment and Ecology Ministry of EducationOcean University of ChinaQingdao 266100P.R.China Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of ChinaQingdao 266100P.R.China

Prorocentrum donghaiense is a dinoflagellate that is widely distributed in the East China Sea and has become increasingly involved in Harmful Algal Blooms (HABs). Therefore, it is necessary to study this dinoflagellate to monitor HABs. In this study, 13 pairs of primers specific to P. donghaiense (within its internal transcribed spacer (ITS) regions) were designed for SYBR Green I real-time PCR. As the SYBR Green I real-time PCR could not identify P. donghaiense in a specific manner, a Taqman real-time PCR method was developed by designing a set of specific primers and a Taqman probe. A 10-fold serial dilution of recombinant plasmid containing ITS regions of P. donghaiense was prepared as standard samples and the standard curve was established. Additionally, we quantified the genomic DNA in P. donghaiense cells and utilized this DNA to prepare another 10-fold serial dilution of standard sample and accordingly set up the standard curve. The mathematic correlation between the cell number and its corresponding plasmid copy number was also established. In order to test the efficiency of the real-time PCR method, laboratory samples and P. donghaiense HAB field samples were employed for identification and quantitative analysis. As to laboratory samples, as few as 102 cells of P. donghaiense could be quantified precisely utilizing both centrifugation and filtration techniques. The quantification results from field samples by real-time PCR were highly similar to those by light microscopy. In conclusion, the real-time PCR could be applied to identify and quantify P. donghaiense in HABs.

关键词： Prorocentrum donghaiense Harmful Algal Blooms (HABs) internal transcribed spacer (ITS) recombinant plasmid real-time PCR

Plankton community composition in the Three Gorges Reservoir Region revealed by PCR-DGGE and its relationships with environmental factors

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Journal of Environmental Sciences 2008年第6期20卷 732-738页

作者： YAN Qingyun yu yuhe FENG Weisong yu zhigang CHEN Hongtao Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Ocean University of China Qingdao 266003 China

To explore the relationships between community composition and the environment in a reservoir ecosystem, plankton communities from the Three Gorges Reservoir Region were studied by PCR-denaturing gradient gel electrophoresis fingerprinting. Bacterial and eukaryotic operational taxonomic units （OTUs）, generated by DGGE analysis of the PCR-amplified 16S and 18S rRNA genes, were used as surrogates for the dominant ＂biodiversity units＂. OTU composition among the sites was heterogeneous; 46.7% of the total bacterial OTUs （45） and 64.1% of the eukaryotic OTUs （39） were identified in less than half of the sampling sites. Unweighted pair group method with arithmetic averages （UPGMA） clustering of the OTUs suggested that the plankton communities in the Xiangxi Rive sites were not always significantly different from those from the Yangtze River sites, despite clear differences in their environmental characterizations. Canonical correspondence analysis （CCA） was applied to further investigate the relationships between OTU composition and the environmental factors. The first two CCA ordination axes suggested that the bacterial community composition was primarily correlated with the variables of NO3^--N, dissolved oxygen （DO）, and SiO3^2--Si, whereas, the eukaryotic community was mainly correlated with the concentrations of DO, PO4^3--P, and SiO3^2--Si.

关键词： plankton community environmental factors denaturing gradient gel electrophoresis (DGGE) spatial pattern Three Gorges Reservoir Region

Influence of N, P, Fe Nutrients Availability on Nitrogen Metabolism-Relevant Genes Expression in Skeletonema marinoi

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Journal of Ocean University of China 2019年第1期18卷 239-252页

作者： JING Xiaoli MI Tiezhu ZHEN yu WANG Hualong yu zhigang College of Marine Life Science Ocean University of China Function Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and Technology Key Laboratory of Marine Environment and Ecology Ministry of Education College of Environmental Science and Engineering Ocean University of China Key Laboratory of Marine Chemical Theory and Technology Ministry of Education

Nitrogen(N), Phosphorus(P), and Iron(Fe) are essential elements for cellular structure and metabolism. In addition to dissolved inorganic nitrogen(DIN), phytoplankton is able to utilize dissolved organic nitrogen(DON). There is general consensus that both bacteria and higher plants nitrogen metabolism is affected by phosphate availability; this was also found to be true in coccolithophorid. Iron affects the structure and function of ecosystems through its effects on nitrogen metabolism. However, it is unclear how these nutrients affect Skeletonema marinoi's nitrogen metabolism. Here, using RT-qPCR, we investigate effects of N, P, and Fe on S. marinoi's nitrogen metabolism and nitrate reductase activity. These results illuminate that in S. marinoi, various nutrients have direct regulation on these genes expression at the molecular level. The varying degree of responses for these genes expression with differing N sources may act to increase the efficiency of nutrient capture when nitrate is limited. Suitable gene expression occurs at a N/P ratio of 16, which represents the atomic N/P ratio of phytoplankton cells and N/P concentrations in ocean; thus, nitrogen metabolism gene expression should be regulated by the existing N/P ratios in the phytoplankton's internal and external environment. Fe concentration has a direct and significant effect on nitrogen metabolism by regulating gene expression and nitrate reductase activity. Gene expression profiles identified in S. marinoi provide a foundation for understanding molecular mechanisms behind diatom nitrogen metabolism with changing N, P, and Fe nutrients allowing a basic understanding of how diatom growth is affected by nutrient utilization.

关键词： Skeletonema marinoi nitrogen metabolism relative gene expression RT-qPCR

Seasonal and spatial distribution of ammonia-oxidizing microorganism communities in surface sediments from the East China Sea

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Acta Oceanologica Sinica 2015年第8期34卷 83-92页

作者： HE Hui ZHEN yu MI Tiezhu LU Xinglan yu zhigang College of Marine Life Science Ocean University of China Key Laboratory of Marine Environment and Ecology Ministry of Education College of Environmental Science and Engineering Qingdao Key Laboratory of Marine Chemical Theory and Technology Ministry of Education

Ammonia oxidation plays a significant role in the nitrogen cycle in marine sediments. Seasonal and spatial distribution of ammonia-oxidizing archaea （AOA） and betaproteobacteria （13-AOB） in surface sediments from the East China Sea （ECS） were investigated using ammonia monooxygenase ct subunit （amoA） gene. In order to characterize the community of AOA and 13-AOB, real-time quantitative polymerase chain reaction （qPCR） was carried out in this study, along with environmental parameters. The abundance of 13-AOB amoA gene （2.17x 10^6-4.54x10^7 copy numbers per gram wet weight sediment） was always greater than that ofAOA amoA gene （2.18x 105-9.89x 10^6 copy numbers per gram wet weight sediment） in all sampling stations. The qPCR results were correlated with environmental parameters. AOA amoA gene copy numbers in April were positively related to temperature and nitrite concentration （p〈0.05）. 13-AOB amoA gene copy numbers in August correlated negatively with salinity （p〈0.01）, and correlated positively with ammonium concentration （p〈0.05）. With the increase of salinity, the amoA gene copy ratio of AOB to AOA had a tendency to decrease, which suggested 13-AOB dominated in the area of high level ammonium and AOA preferred high salinity area.

关键词： ammonia-oxidizing microorganisms sediment East China Sea