14 resultados para Making and Evaluating Strategy: Learning from the Military

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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A new sulfur-containing guanidino derivative, halichondria sulfonic acid (1) showing anti-HIV-1 activity, and halistanol trisulfate (2) with anti-tumor activity have been isolated from the marine sponge Halichondria rugosa Ridley & Dendy collected in the

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Bioavailable water concentrations of polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and organochlorine pesticides (OCP) were measured in the water column from Three Gorges Reservoir (TGR) collected in May 2008 using semipermeable membrane devices (SPMDs). The sampling sites spanned the whole reservoir from the upstream Chongqing to the great dam covering more than 600 km long distance with water flow velocities ranging from <0.05 to 1.5 m s(-1). This is the first experience of SPMD application in the biggest reservoir in the world. The results of water sampling rates based on performance reference compounds (PRC) were tested to be significantly correlated with water flow velocities in the big river. Results of back-calculated aqueous concentrations based on PRC showed obvious regional variations of PAH, PCB and OCP levels in the reservoir. Total PAH ranged from 13.8 to 97.2 ng L-1, with the higher concentrations occurring in the region of upstream and near the dam. Phenanthrene, fluoranthene, pyrene and chrysene were the predominant PAH compounds in TGR water. Total PCB ranged from 0.08 to 0.51 ng L-1, with the highest one occurring in the region near the dam. PCB 28, 52, 101, 138, 153, 180, 118 were the most abundant PCB congeners in the water. The total OCP ranged from 2.33 to 3.60 ng L-1 and the levels showed homogenous distribution in the whole reservoir. HCH, DDT and HCB, PeCB were the major compounds of OCP fingerprints. Based on water quality criteria, the TGR water could be designated as being polluted by HCB and PAH. Data on PAH, PCB and OCP concentrations found in this survey can be used as reference levels for future POP monitoring programmes in TGR. (C) 2009 Elsevier Ltd. All rights reserved.

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We report on taxa from the diatom genera Gomphonema and Cymbella (Cymbellales, Bacillariophyta) found in the Jolmolungma Mountain region of China. This region is unique for its diversity of habitats, which include rivers, springs, moist soil, snowfields, swamps and lakes. We re-examine diatom taxa found in samples first documented in 1973 (Jao et A, 1973) and incorporate recent taxonomic revisions from the literature. In the genera Gomphonema and Cymbella we report 113 species and varieties. Of these 113 taxa, 59 are new record for China; 1 new combination, Encyonema jolmolungmensis, is made. Morphometric data and habitat features are reported for each taxon. Their distribution is strongly correlated to their microhabitats.

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A tumor necrosis factor receptor-associated factor 2 binding protein (T2BP) gene was isolated from the grass carp (Ctenopharyngodon idellus) by utilizing suppression subtractive hybridization (SSH) and rapid amplification of cDNA ends (RACE). The grass carp T2BP (GT2BP) gene contains an open reading frame of 579 nucleotide(s) (nt), encoding 193 amino acids, with 23 nt 5'-untranslated region and a long 3'-untranslated region of 434 nt including poly (A), 1 AUUUA motif and 4 AUUUUA motifs. No signal peptide has been detected in the predicted GT2BP, but a characteristic forkhead associated domain is present. The GT2BP mRNA shares 83% identity with the zebrafish DNA sequence, and they both have no introns in the genomic DNA. The putative transcription factor binding sites of GT2BP include two C/EBP alpha binding sites, and one c-Jun binding, one AP-1 binding, and one nuclear factor kappa B (NF kappa B) binding sites. Southern blot analysis revealed that the GT2BP was a single-copy gene. Individual difference was observed in GT2BP expression in examined organs of healthy grass carp. However, the expression of GT2BP in all examined organs in a fish with the highest copepod infection level and the significantly higher expression level in spleen and liver in infected fish may indicate its up-regulation with the parasite infection. (c) 2005 Elsevier B.V. All rights reserved.

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A viperin gene has been cloned from the mandarin fish (Siniperca chuatsi). From the first transcription initiation site, the mandarin fish viperin gene extends 3163 nucleotides to the end of the 3' untranslated region, and it contains six exons and five introns. The open reading frame of the viperin transcript has 1062 nucleotides which encode a 354 amino acid peptide. The amino acid sequence of mandarin fish viperin shows high identities with its homologues in teleosts and mammals except for the first 70 amino acids. A characteristic feature in the viperin promoter region was the presence of five putative ICSBP (IRF8) binding sites and one IRFI binding site. The viperin gene expressed mainly in lymphoid tissues before stimulation, but its expression can be examined in almost all the organs investigated after stimulation with virus or Poly I:C. The expression pattern and promoter sequence may be considered as the indirect evidence that the transcription of viperin is regulated by interferons or interferon induced genes. (C) 2004 Elsevier B.V. All rights reserved.

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Extraction and separation of yttrium from the rare earths in chloride medium using sec-octylphenoxy acetic acid (CA-12), tri-n-butyl phosphate (TBP) as modifier, in kerosene has been investigated. The separation coefficients, beta, were obtained and the extraction selectivity has been enhanced when compared with that of naphthenic acid. The experimental results indicated that CA-12-TBP system could be employed to separate yttrium, from rare earths. Fractional extraction (15 stages for extraction and 10 stages for scrubbing) was studied, the raffinate of the first stage was abundant in purity yttrium of 99.5%, with a yield of > 95%, percentage of yttrium in the mixture rare earths was less than 5% in the loaded organic phase of the 25th stage and loaded capability was about 0.2 mol/L.

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Three new polybrominated 1H-indoles, compounds 1-3, and three new aristolane sesquiterpenes, compounds 4-6, were isolated from the marine red alga Laurencia similis, together with seven known natural products. Their structures were elucidated on the basis of detailed spectroscopic and mass-spectrometric analyses, as well as by comparison with literature data.

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Based on Th-230-U-238 disequilibrium and major element data from mid-ocean ridge basalts (MORBs) and ocean island basalts (OIBs), this study calculates mantle melting parameters, and thereby investigates the origin of Th-230 excess. (Th-230/U-238) in global MORBs shows a positive correlation with Fe-8, P (o), Na-8, and F-melt (Fe-8 and Na-8 are FeO and Na2O contents respectively after correction for crustal fractionation relative to MgO = 8 wt%, P (o)=pressure of initial melting and F (melt)=degree of melt), while Th-230 excess in OIBs has no obvious correlation with either initial mantle melting depth or the average degree of mantle melting. Furthermore, compared with the MORBs, higher (Th-230/U-238) in OIBs actually corresponds to a lower melting degree. This suggests that the Th-230 excess in MORBs is controlled by mantle melting conditions, while the Th-230 excess in OIBs is more likely related to the deep garnet control. The vast majority of calculated initial melting pressures of MORBs with excess Th-230 are between 1.0 and 2.5 GPa, which is consistent with the conclusion from experiments in recent years that D (U)> D (Th) for Al-clinopyroxene at pressures of > 1.0 GPa. The initial melting pressure of OIBs is 2.2-3.5 GPa (around the spinel-garnet transition zone), with their low excess Ra-226 compared to MORBs also suggesting a deeper mantle source. Accordingly, excess Th-230 in MORBs and OIBs may be formed respectively in the spinel and garnet stability field. In addition, there is no obvious correlation of K2O/TiO2 with (Th-230/U-238) and initial melting pressure (P (o)) of MORBs, so it is proposed that the melting depth producing excess Th-230 does not tap the spinel-garnet transition zone. OIBs and MORBs in both (Th-230/U-238) vs. K2O/TiO2 and (Th-230/U-238) vs. P (o) plots fall in two distinct areas, indicating that the mineral phases which dominate their excess Th-230 are different. Ce/Yb-Ce curves of fast and slow ridge MORBs are similar, while, in comparison, the Ce/Yb-Ce curve for OIBs shows more influence from garnet. The mechanisms generating excess Th-230 in MORBs and OIBs are significantly different, with formation of excess Th-230 in the garnet zone only being suitable for OIBs.

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Four new species, Eudesme huanghaiensis Ding et Lu, E. qingdaoensis Ding et Lu, E. shandongensis Ding et Lu and Sphaerotrichia huanghaiensis Ding et Lu, from the western Yellow Sea coast of China are described. Eudesme huanghaiensis is mainly characterized by its spherical or sub-spherical sub-cortical cells, its rhizoidal filaments developing from the basal cells of sub-cortex and its broad sub-cortical and medullary layers. E. qingdaoensis is mainly characterized by its long medullary cells, generally hollow center of the medulla, short sub-cortex with only 3-4 cylindrical cells and long, slender and clavate terminal cells of the rhizoidal filaments. E. shandongensis is mainly characterized by its hollow frond, thick cell walls of both medulla and inner sub-cortical layers and the spherical terminal cells of the rhizoid filaments. Sphaerotrichia huanghaiensis is mainly characterized by its cylindrical, sparsely branched frond with acute angle, and its thick 5-6 layered sub-cortex with long assimilating filaments of 6-10 cells.

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Three homologous short-chain neurotoxins, named NT1, NT2 and NT3, were purified from the venom of Naja kaouthia. NT1 has an identical amino acid sequence to cobrotoxin from Naja naja atra [Biochemistry 32 (1993) 2131]. NT3 shares the same sequence with cobrotoxin b [J. Biochem. (Tokyo) 122 (1997) 1252], whereas NT2 is a novel 6 1 -residue neurotoxin. Tests of their physiological functions indicate that NT1 shows a greater inhibition of muscle contraction induced by electrical stimulation of the nerve than do NT2 and NT3. Homonuclear proton two-dimensional NMR methods were utilized to study the solution tertiary structure of NT2. A homology model-building method was employed to predict the structure of NT3. Comparison of the structures of these three toxins shows that the surface conformation of NT1 facilitates the substituted base residues, Arg28, Arg30, and Arg36, to occupy the favorable spatial location in the central region of loop 11, and the cation groups of all three arginines face out of the molecular surface of NT1 This may contribute greatly to the higher binding of NT1 with AchR compared to NT2 and NT3. (C) 2002 Elsevier Science B,V. All rights reserved.

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Surface sediments and bivalves were collected from the Changjiang Estuary in December 2003 and November 2004, respectively. Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in these samples were measured with high-resolution chromatography (HRGC)/High Resolution Mass Spectrometer (HRMS). The concentrations of total PCDD/Fs and toxic equivalent (TEQ) were 169.83 +/- 119.63 and 0.81 +/- 0.36 pg/g dry weight (dw) in sediments, and 580.33 +/- 240.17 and 7.24 +/- 3.65 pg/g dw in bivalves. The homolog compositions of PCDD/Fs were similar among samples, the most abundant congener was octa-chlorinated dibenzo-p-dioxin (OCDD) and then octa-chlorinated dibenzofuran (OCDF) and 1,2,3,4,6,7,8-hepta-chlorinated dibenzo-p-dioxin (HOCDD). The herbicide pentachlorophenol (PCP) and sodium pentachlorophenol (Na-PCP) were proved the main source of PCDD/Fs in this area.

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Living planktonic foraminifera (PF) samples from the Okinawa Trough of the northwestern Pacific Ocean were taken for DNA analysis. The SSU rDNA sequences of two PF species, Globigerina sp. and Pulleniatina obliquiloculata collected at Station WP01, were obtained and compared with those from the southwestern Pacific Ocean. Only small differences (< 0.7%-1.2% for P. obliquiloculata, and 0.3% for Globigerina sp.) were found between samples from the north- and south-western Pacific Ocean areas and this molecular evidence supported that these micropaleontological species are the same species, which implies that the West Pacific Ocean circulation system influences the planktonic foraminiferal gene communication.