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Have a correct understanding of the attribute of geologic environmentgive full play to the role of geoscience in environmental protection

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Journal of Environmental sciences 1995年第4期7卷 491-501页

作者： Ha Chengyou(institute of Environmental geology, Ministry of geology and {3. resources, beijing 100081 , china)

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关键词： geologic environment attribute geologic resources geologic capacity geologic disaster.

The effects of K^+ growth conditions on the accumulation of cesium by the bacterium Thermus sp. TibetanG6

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Science china(Life sciences) 2006年第2期49卷 123-129页

作者： WANG Hailei1,2,3. KONG Fanjing1,2,3.& ZHENG Mianping1,2,3.1. R&D Center for Saline Lake and Epithermal Deposits, chinese Academy of Geological sciences, beijing 10003.,{3. 2. key Open laboratory of Saline Lake resources and Environment, chinese Academy of Geological sciences, beijing 10003.,{3. 3. institute of mineral resources, chinese Academy of Geological sciences, beijing 10003.,{3. R&D Center for Saline Lake Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China key Open laboratory of Saline Lake resources Environment Chinese Academy of Geological Sciences Beijing 100037 China institute of mineral resources Chinese Academy of Geological Sciences Beijing 100037 China

The accumulation of cesium by the bacterium Thermus sp. TibetanG6 was examined under different K+ growth conditions. The effects of external pH and Na+ on the accumulation of ce-sium were also studied, and the mechanism involved was discussed. K+ regimes played an important role in the accumulation of cesium by the strain TibetanG6. The quantity of cesium accumulated (24 h) was much higher in K+-deficient regime than that in K+-sufficient regime. The pH and Na+ had different effects on the accumulation of cesium in the two K+ regimes. IR spectra analyses indicated that the biosorption is a process of homeostasis with cesium initially accumulated on the cell wall.

关键词： Thermus sp. TibetanG6, cesium, bioaccumulation, K+-growth condition, pH, sodium, IR spectroscopy.

Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2, LIU Yu2 & TAN Ming3.. South china Sea institute of Oceanology, chinese Academy of {3.. Guangzhou 5103.1, china 2. State key laboratory of Loess and Quaternary geology, Earth Environmental institute, chinese Academy of {3., Xi’an 710075, china 3. institute of geology and geophysics, chinese Academy of {3., beijing 100029, china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China State key laboratory of Loess and Quaternary geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of geology and geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

Role of ubiquitination in meiotic recombination repair

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Science china(Life sciences) 2010年第4期53卷 447-454页

作者： CUI Li & LI Wei State key laboratory of Reproductive Biology, institute of Zoology, {3. Academy of sciences, beijing 100101, china 1. State key laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Programmed and unprogrammed double-strand breaks (DSBs) often arise from such physiological requirements as meiotic recombination, and exogenous insults, such as ionizing radiation (IR). Due to deleterious impacts on genome stability, DSBs must be appropriately processed and repaired in a regulatory manner. Recent investigations have indicated that ubiquitination is a critical factor in DNA damage response and meiotic recombination repair. This review summarizes the effects of proteins and complexes associated with ubiquitination with regard to homologous recombination (HR)-dependent DSB repair.

关键词： ubiquitin meiosis homologous recombination DNA double-strand breaks

Molecular basis of cryptorchidism-induced infertility

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Science china(Life sciences) 2010年第11期53卷 1274-1283页

作者： LIU YiXun & LI XiXia State key laboratory of Reproductive Biology, institute of Zoology, {3. Academy of sciences, beijing 100101, china 1. State key laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Artificial cryptorchidism or local testicular heat treatment can induce reversible oligospermia or azoospermia in monkeys and rats via germ cell apoptosis. Local warming of monkey testes in water at 43.C for 2 consecutive days (3. min per day) decreased the number of sperm in the semen by up to 80% on d 28, and the effect was completely reversed on d 144. Germ cells rely heavily on Sertoli cells for structural and nutritional support. Specialized junctions that play a pivotal role in spermatogenesis occur at sites of Sertoli-Sertoli and Sertoli-germ cell contact in the seminiferous epithelium. We demonstrated that expression of tight junction (TJ)-associated molecules, such as occludin and zonula occludens-1 (ZO-1), were greatly reduced 24–48 h after heat treatment, while the permeability of the blood-testis barrier (BTB) was simultaneously increased, but recovered 10 d later. These results indicate a reversible disruption of the BTB associated with transient inductions of transforming growth factor (TGF) β2 and β3.expression, p3. mitogen-activated protein kinase and extracellular signal-regulated kinase activation, and concomitant loss of occludin and ZO-1. This suggests that expression of TJ-associated molecules and the BTB was reversibly perturbed by mild testicular hyperthermia, and that the heat-induced induction of TGF-β might be involved in downregulating TJ-associated proteins, leading to cell junction reduction. This review discusses the changes in total gene expression patterns after experimental cryptorchidism in adult mouse testes, and the cloning of several novel, physiologically significant spermatogenesis-specific genes.

关键词： cryptorchidism spermatogenesis apoptosis heat stress Sertoli cells blood-testis barrier tight junction

Vermiform trace fossils from the Precambrian Ruyang Group, western Henan

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chinese Science Bulletin 1997年第3期42卷 251-254页

作者： HU Jianmin, MENG Qingren and LI Wenhou1 Xi’ an College of geology, Xi’an 710054, china 2. institute of {3., chinese Academy of sciences, beijing 100101, china 3.Department of geology, Northwest University, Xi’an 710069, china Xi’an College of geology Xi’an China institute of geophysics Chinese Academy of Sciences Beijing China Department of geology Northwest University Xi’an China

THE origin and evolution of Precambrian lives has been a long-standing controversial problem. It is now generally accepted by most paleontologists that the origin of metazoa can be traced back to more than 1000 Ma, because the Ediacara and latest pre-Ediacara fauna, such as the Huainan fauna, are featured by their diversification of forms, complicated structures

关键词： Precambrian trace fossil Ruyang Group.

Indosinian Foreland Fold-and-Thrust Belt Bordering Yunnan and Guangxi, china

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 391-397页

作者： WU Genyao institute of geology and geophysics, chinese Academy of sciences, {3. 100029 institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 [?]2Wu Genyao Male born in 1946 graduated from the Department of geology Peking University in 1968 obtained a DSc degree in 1985 now a research professor with the institute of geology and geophysics Chinese Academy of Sciences. His main research interest is regional tectonics and he has been working on the tethysides in South China and adjacent areas since 1987. Tel: (010) 62008118 Fax: (010) 62010846 E-mail: dizhikx@***

Recent discoveries of ophiolites indicate that there must be a Palaeotethyan geosuture zone bordering china and Vietnam, which separates the Vietbac block from the South china subcontinent. The Indosinian foreland fold-and-thrust belt bordering Yunnan and Guangxi provided further evidence for the palaeotethysides. The oceanic crust was subducted southwestwards while the magmatic arc migrated northeastwards, and the continent-arc collision occurred in the Late Triassic with the thrusting being extended towards the north or northeast. The features of thrust-nappe structure are discussed, which proved the continental margin of the Palaeotethyan ocean there to be a complicated one. A face-to-face collision occurred first along the NW-striking segment and then along the ENE-striking segment accompanied by transpression or oblique thrusting occurring along the NW-striking one.

关键词： thrust-nappe structure foreland fold-and-thrust belt palaeotethysides border between Yunnan and Guangxi

Four new species and a new chinese record of the nectrioid fungi

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Science china(Life sciences) 2010年第8期53卷 909-915页

作者： LUO Jing & ZHUANG WenYing key laboratory of Systematic Mycology and Lichenology, institute of Microbiology, {3. Academy of sciences, beijing 100101, china 1. key laboratory of Systematic Mycology and Lichenology Institute of Microbiology Chinese Academy of Sciences Beijing 100101 China

Four new species belonging to Bionectria, Calonectria, Haematonectria and Neonectria on plant substrates collected from nature reserves in southern and central china are described. Bionectria truncata has smooth perithecia of a flattened to shallow discoid apex, clavate asci with an apical ring, and ellipsoid, smooth to spinulose ascospores. Calonectria dicephalospora is characterized by pyriform perithecia with a warted surface, clavate asci with a simple apex and long, narrow stalk, and fusoid ascospores with a cap-like appendage at each end. Haematonectria lushanensis possesses warted perithecia which are laterally collapsing when dry, cylindrical asci with a simple apex, and ellipsoid, spinulose ascospores. Neonectria dinghushanica is distinguishable by subglobose perithecia with a warted surface, clavate asci, and striate ascospores. Morphological features of these new species are described comprehensively and compared with their related fungi. Neonectria castaneicola is recorded as new to china.

关键词： Bionectriaceae Nectriaceae morphology taxonomy

Spectroscopic evidence for triplet excitation energy transfer among carotenoids in the LH2 complex from photosynthetic bacterium Rhodopseudomonas palustris

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Science china Chemistry 2004年第1期47卷 80-90页

作者： FENG Juan, WANG Qian, ZHANG Xujia, HUANG Youguo, Al Xicheng, ZHANG Xingkang & ZHANG JianpingState key laboratory for Structural Chemistry of Unstable and Stable Species, institute of Chemistry, {3. Academy of sciences, beijing 100080, china National laboratory of Biomacromolecules, institute of Biophysics, {3. Academy of sciences, beijing 100101, china 1. State key laboratory for Structural Chemistry of Unstable and Stable Species institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 2. National laboratory of Biomacromolecules institute of Biophysics Chinese Academy of Sciences 100101 Beijing China

The LH2 complex from Rhodopsudomonas (Rps.) palustris is unique in the heterogeneous carotenoid compositions. The dynamics of triplet excited state Carotenoids (3.ar* has been investigated by means of sub-microsecond time-resolved absorption spectroscopy both at physiological temperature (295 K) and at cryogenic temperature (77K). Broad and asymmetric T n ←T 1 transient absorption was observed at room temperature following the photo-excitation of Car at 53. nm, which suggests the contribution from various carotenoid compositions having different numbers of conjugated C=C double bonds (Nc=c). The triplet absorption bands of different carotenoids, which superimposed at room temperature, could be clearly distinguished upon decreasing the temperature down to 77 K. At room temperature the shorter-wavelength side of the main Tn04T1 absorption band decayed rapidly to reach a spectral equilibration with a characteristic time constant of ∽1 μs, the same spectral dynamics, however, was not observed at 77 K. The aforementioned spectral dynamics can be explained in terms of the triplet-excitation transfer among heterogeneous carotenoid compositions. Global spectral analysis was applied to the time-resolved spectra at room temperature, which revealed two spectral components peaked at 545 and 565 nm, and assignable to the Tn04 T1 absorption of Cars with Nc=c=11 and Nc=c=13. respectively. Surprisingly, the decay time constant of a shorter-conjugated Car, i.e. 0.72 ?s (aerobic) and 1.3. ?s (anaerobic), is smaller than that of a longer-conjugated Car, i.e. 2.12 us (aerobic) and 3.75 ?s (anaerobic), which is contradictory to the general rule of carotenoids and relative polyenes. The results are explained in terms of triplet-excitation transfer among different types of Cars. It is postulated that two Cars with different conjugation lengths coexist in an α, β-subunit in the LH2 complex.

关键词： purple photosynthetic bacteria, carotenoid, excited-state, time-resolved spectroscopy.