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Sample records for acid auxotrophs constructed

  1. Arabidopsis thaliana auxotrophs reveal a tryptophan-independent biosynthetic pathway for indole-3-acetic acid.

    Normanly, J; Cohen, J D; Fink, G. R.

    1993-01-01

    We used tryptophan auxotrophs of the dicot Arabidopsis thaliana (wall cress) to determine whether tryptophan has the capacity to serve as a precursor to the auxin, indole-3-acetic acid (IAA). Quantitative gas chromatography-selected ion monitoring-mass spectrometry (GC-SIM-MS) revealed that the trp2-1 mutant, which is defective in the conversion of indole to tryptophan, accumulated amide- and ester-linked IAA at levels 38-fold and 19-fold, respectively, above those of the wild type. Tryptopha...

  2. Amino acid precursors for the detection of transketolase activity in Escherichia coli auxotrophs.

    Simon, Grégory; Bouzon, Madeleine; Charmantray, Franck; Hélaine, Virgil; Légeret, Bertrand; Marlière, Philippe; Hecquet, Laurence

    2009-07-15

    Probes were developed for the in vivo detection of transketolase activity by the use of a complementation assay in Escherichia coli auxotrophs They combine the d-threo ketose moiety recognised by transketolase and the side chain of leucine or methionine. These compounds were donor substrates of yeast transketolase leading to the release of the corresponding alpha-hydroxyaldehydes which could be converted in E. coli by a cascade of reactions into leucine or methionine required for cellular growth. PMID:19535247

  3. Influence of unsaturated fatty acids, membrane fluidity and oxygenation on the survival of an E. coli fatty acid auxotroph following γ-irradiation

    Escherichia coli K1060, a fatty acid auxotroph unable to either synthesize or degrade unsaturated fatty acids (uFAs), was used to study the effect of membrane fluidity on survival after exposure to ionizing radiation. Using this strain of E. coli, significant alterations in the fatty acid composition of the membrane have been produced and verified by gas chromatography. linolenic, oleic, elaidic and palmitelaidic acids were the uFAs used. Survival above the transition temperature (Tsub(t)) (liquid crystal reversible gel) was comparable for these fatty-acid-supplemented membranes after exposure to γ-irradiation, whereas γ-irradiation below Tsub(t) resulted in a significant decrease in survival. An oxygen enhancement effect was observed for each experimental condition employed. (author)

  4. Possible involvement of a plasmid in arginine auxotrophic mutation of Streptomyces kasugaensis.

    Nakano, M M; Ozawa, K; Ogawara, H

    1980-01-01

    Streptomyces kasugaensis gave arginine auxotrophic mutants at high frequency, The coupled loss and reappearance of plasmid deoxyribonucleic acid with arginine auxotrophy suggested that the insertion of the plasmid into chromosomal deoxyribonucleic acid caused the arginine auxotrophy.

  5. L-Tryptophan Production by Auxotrophic and Analogue Resistant Mutants of Aureobacterium flavescens

    Roy, A; S.K. Mukhopadhyay

    2011-01-01

    A number of tyrosine plus phenylalanine double auxotrophic mutants were isolated by N-methyl-N-nitro-N-nitrosoguanidine (MNNG) treatment of a locally isolated strain of Aureobacterium flavescens of which 11A39 and 11A17 were selected on the basis of their tryptophan production in a mineral salt medium over other isolated mutant strains. The mutational block in the aromatic amino acid biosynthetic pathway of the selected double auxotrophs were determined. By controlling pH of the production me...

  6. Enrichment of Auxotrophic Mutants in Streptomyces griseus

    Werner, Rolf G.; Demain, Arnold L.

    1980-01-01

    A method for the isolation and enrichment of tryptophan auxotrophic mutants of the indolmycin-producing strain Streptomyces griseus ATCC 12648 was developed, using penicillin selection. With UV irradiation of 2.2 × 104 μW cm−2, a mutation rate to tryptophan auxotrophy of 5.6 × 10−4 was achieved. With 300 μg ml−1 of penicillin G, an enrichment of tryptophan auxotrophs of about 1,000-fold was attained. Approximately 40% of all survivors were tryptophan auxotrophs.

  7. Auxotrophic complementation as a selectable marker for stable expression of foreign antigens in Mycobacterium bovis BCG.

    Borsuk, Sibele; Mendum, Tom A; Fagundes, Michel Quevedo; Michelon, Marcelo; Cunha, Cristina Wetzel; McFadden, Johnjoe; Dellagostin, Odir Antônio

    2007-11-01

    Mycobacterium bovis BCG has the potential to be an effective live vector for multivalent vaccines. However, most mycobacterial cloning vectors rely on antibiotic resistance genes as selectable markers, which would be undesirable in any practical vaccine. Here we report the use of auxotrophic complementation as a selectable marker that would be suitable for use in a recombinant vaccine. A BCG auxotrophic for the amino acid leucine was constructed by knocking out the leuD gene by unmarked homologous recombination. Expression of leuD on a plasmid not only allowed complementation, but also acted as a selectable marker. Removal of the kanamycin resistance gene, which remained necessary for plasmid manipulations in Escherichia coli, was accomplished by two different methods: restriction enzyme digestion followed by re-ligation before BCG transformation, or by Cre-loxP in vitro recombination mediated by the bacteriophage P1 Cre Recombinase. Stability of the plasmid was evaluated during in vitro and in vivo growth of the recombinant BCG in comparison to selection by antibiotic resistance. The new system was highly stable even during in vivo growth, as the selective pressure is maintained, whereas the conventional vector was unstable in the absence of selective pressure. This new system will now allow the construction of potential recombinante vaccine strains using stable multicopy plasmid vectors without the inclusion of antibiotic resistance markers. PMID:17888740

  8. Construction of a Food Grade Recombinant Bacillus subtilis Based on Replicative Plasmids with an Auxotrophic Marker for Biotransformation of d-Fructose to d-Allulose.

    He, Weiwei; Mu, Wanmeng; Jiang, Bo; Yan, Xin; Zhang, Tao

    2016-04-27

    A food grade recombinant Bacillus subtilis that produces d-psicose 3-epimerase (DPEase; EC 5.1.3.30) was constructed by transforming a replicative multicopy plasmid with a d-alanine racemase gene marker into B. subtilis 1A751 with the d-alanine racemase gene knocked out. The DPEase was expressed in B. subtilis without antibiotic resistance genes and without adding antibiotics during fermentation. Whole cells of the food grade recombinant B. subtilis were used to biotransform d-fructose to d-allulose. The two tandem promoters, including the HpaII and P43 promoters, increased expression levels compared to the use of one promoter, HpaII. For large-scale d-allulose production, the optimal enzyme dose was 40 enzyme activity units of dry cells per gram of d-fructose, which produced a 28.5% turnover yield in 60 min. The recombinant plasmid exhibited stability over 100 generations. This food grade recombinant B. subtilis may be used for large-scale d-allulose production in the food industry. PMID:27056339

  9. Generation of a Uracil Auxotroph Strain of the Probiotic Yeast Saccharomyces boulardii as a Host for the Recombinant Protein Production.

    Hamedi, Hassan; Misaghi, Ali; Modarressi, Mohammad Hossein; Salehi, Taghi Zahraei; Khorasanizadeh, Dorsa; Khalaj, Vahid

    2013-01-01

    BACKGROUND: Saccharomyces boulardii (S. boulardii) is the best known probiotic yeast. The genetic engineering of this probiotic strain requires the availability of appropriate mutants to accept various gene constructs carrying different selection markers. As the auxotrophy selection markers are under focus, we have generated a ura3 auxotroph mutant of S. boulardii for use in further genetic manipulations. METHODS: Classical UV mutagenesis was used for the generation of auxotroph mutants. The ...

  10. Tryptophan auxotrophs of Rhizobium japonicum.

    Wells, S E; Kuykendall, L D

    1983-01-01

    Eleven tryptophan-requiring mutants of Rhizobium japonicum I-110 ARS were isolated after nitrous acid mutagenesis and fell into five groups based on characterization by supplementation with intermediates and enzyme assays.

  11. Tryptophan auxotrophs were obtained by random transposon insertions in the Methanococcus maripaludis tryptophan operon.

    Porat, Iris; Whitman, William B

    2009-08-01

    Methanococcus maripaludis is an anaerobic, methane-producing archaeon that utilizes H(2) or formate for the reduction of CO(2) to methane. Tryptophan auxotrophs were constructed by in vitro insertions of the Tn5 transposon into the tryptophan operon, followed by transformation into M. maripaludis. This method could serve for rapid insertions into large cloned DNA regions. PMID:19566682

  12. Tryptophan auxotrophs were obtained by random transposon insertions in the Methanonococcus maripaludis tryptophan operon

    Porat, Iris; Whitman, William B.

    2009-01-01

    Methanococcus maripaludis is an anaerobic, methane-producing archaeon that utilizes H2 or formate for the reduction of CO2 to methane. Tryptophan auxotrophs were constructed by in vitro insertions of the Tn5 transposon into the tryptophan operon, followed by transformation into M. maripaludis. This method could serve for rapid insertions into large cloned DNA regions.

  13. A conserved suppressor mutation in a tryptophan auxotroph results in dysregulation of Pseudomonas quinolone signal synthesis.

    Knoten, Claire A; Wells, Greg; Coleman, James P; Pesci, Everett C

    2014-07-01

    Pseudomonas aeruginosa is a common nosocomial pathogen that relies on three cell-to-cell signals to regulate multiple virulence factors. The Pseudomonas quinolone signal (PQS; 2-heptyl-3-hydroxy-4-quinolone) is one of these signals, and it is known to be important for P. aeruginosa pathogenesis. PQS is synthesized in a multistep reaction that condenses anthranilate and a fatty acid. In P. aeruginosa, anthranilate is produced via the kynurenine pathway and two separate anthranilate synthases, TrpEG and PhnAB, the latter of which is important for PQS synthesis. Others have previously shown that a P. aeruginosa tryptophan auxotroph could grow on tryptophan-depleted medium with a frequency of 10(-5) to 10(-6). These revertants produced more pyocyanin and had increased levels of phnA transcript. In this study, we constructed similar tryptophan auxotroph revertants and found that the reversion resulted from a synonymous G-to-A nucleotide mutation within pqsC. This change resulted in increased pyocyanin and decreased PQS, along with an increase in the level of the pqsD, pqsE, and phnAB transcripts. Reporter fusion and reverse transcriptase PCR studies indicated that a novel transcript containing pqsD, pqsE, and phnAB occurs in these revertants, and quantitative real-time PCR experiments suggested that the same transcript appears in the wild-type strain under nutrient-limiting conditions. These results imply that the PQS biosynthetic operon can produce an internal transcript that increases anthranilate production and greatly elevates the expression of the PQS signal response protein PqsE. This suggests a novel mechanism to ensure the production of both anthranilate and PQS-controlled virulence factors. PMID:24748618

  14. Targeting tumors with nonreplicating Toxoplasma gondii uracil auxotroph vaccines.

    Fox, Barbara A; Sanders, Kiah L; Chen, Shan; Bzik, David J

    2013-09-01

    Toxoplasma gondii is an intracellular parasite that has evolved to actively control its invaded host cells. Toxoplasma triggers then actively regulates host innate interleukin-12 (IL-12) and interferon-γ (IFN-γ) responses that elicit T cell control of infection. A live, nonreplicating avirulent uracil auxotroph vaccine strain (cps) of Toxoplasma triggers novel innate immune responses that stimulate amplified CD8(+) T cell responses and life-long immunity in vaccinated mice. Here, we review recent reports showing that intratumoral treatment with cps activated immune-mediated regression of established solid tumors in mice. We speculate that a better understanding of host-parasite interaction at the molecular level and applying improved genetic models based on Δku80 Toxoplasma strains will stimulate development of highly effective immunotherapeutic cancer vaccine strategies using engineered uracil auxotrophs. PMID:23928100

  15. Targeting tumors with nonreplicating Toxoplasma gondii uracil auxotroph vaccines

    Fox, Barbara A.; Sanders, Kiah L; Chen, Shan; Bzik, David J.

    2013-01-01

    Toxoplasma gondii is an intracellular parasite that has evolved to actively control its invaded host cells. Toxoplasma triggers then actively regulates host innate IL-12 and interferon-γ responses that elicit T cell control of infection. A live, nonreplicating avirulent uracil auxotroph vaccine strain (cps) of Toxoplasma triggers novel innate immune responses that stimulate amplified CD8+ T cell responses and life-long immunity in vaccinated mice. Here, we review recent reports showing that i...

  16. Avirulent Uracil Auxotrophs Based on Disruption of Orotidine-5′-Monophosphate Decarboxylase Elicit Protective Immunity to Toxoplasma gondii ▿ †

    Fox, Barbara A.; Bzik, David J.

    2010-01-01

    The orotidine-5′-monophosphate decarboxylase (OMPDC) gene, encoding the final enzyme of the de novo pyrimidine biosynthesis pathway, was deleted using Toxoplasma gondii KU80 knockouts to develop an avirulent nonreverting pyrimidine auxotroph strain. Additionally, to functionally address the role of the pyrimidine salvage pathway, the uridine phosphorylase (UP) salvage activity was knocked out and a double knockout of UP and OMPDC was also constructed. The nonreverting ΔOMPDC, ΔUP, and ΔOMPDC ...

  17. HANDBOOK FOR CONSTRUCTED WETLANDS RECEIVING ACID MINE DRAINAGE

    In the summer of 1987, a pilot constructed wetland was built at the Big Five Tunnel in Idaho Springs, Colorado. This report details the theory, design and construction of wetlands receiving acid mine drainages, based on the second and third year of operation of this wetland, whic...

  18. Dithizone staining of intracellular zinc: an unexpected and versatile counterscreen for auxotrophic marker genes in Saccharomyces cerevisiae.

    Daniel S Yuan

    Full Text Available Auxotrophic marker genes such as URA3, LEU2, and HIS3 in Saccharomyces cerevisiae have long been used to select cells that have been successfully transformed with recombinant DNA. A longstanding challenge in working with these genes is that counterselection procedures are often lacking. This paper describes the unexpected discovery of a simple plate assay that imparts a bright red stain to cells experiencing nutritional stress from the lack of a marker gene. The procedure specifically stains a zinc-rich vesicular compartment analogous to the zinc-rich secretory vesicles found in insulin-secreting pancreatic islet cells and glutamate-secreting neurons. Staining was greatly diminished in zap1 mutants, which lack a homeostatic activator of zinc uptake, and in cot1 zrc1 double mutants, which lack the two yeast homologs of mammalian vesicle-specific zinc export proteins. Only one of 93 strains with temperature-sensitive alleles of essential genes exhibited an increase in dithizone staining at its non-permissive temperature, indicating that staining is not simply a sign of growth-arrested or dying cells. Remarkably, the procedure works with most commonly used marker genes, highlights subtle defects, uses no reporter constructs or expensive reagents, requires only a few hours of incubation, yields visually striking results without any instrumentation, and is not toxic to the cells. Many potential applications exist for dithizone staining, both as a versatile counterscreen for auxotrophic marker genes and as a powerful new tool for the genetic analysis of a biomedically important vesicular organelle.

  19. Avirulent uracil auxotrophs based on disruption of orotidine-5'-monophosphate decarboxylase elicit protective immunity to Toxoplasma gondii.

    Fox, Barbara A; Bzik, David J

    2010-09-01

    The orotidine-5'-monophosphate decarboxylase (OMPDC) gene, encoding the final enzyme of the de novo pyrimidine biosynthesis pathway, was deleted using Toxoplasma gondii KU80 knockouts to develop an avirulent nonreverting pyrimidine auxotroph strain. Additionally, to functionally address the role of the pyrimidine salvage pathway, the uridine phosphorylase (UP) salvage activity was knocked out and a double knockout of UP and OMPDC was also constructed. The nonreverting DeltaOMPDC, DeltaUP, and DeltaOMPDC DeltaUP knockout strains were evaluated for pyrimidine auxotrophy, for attenuation of virulence, and for their ability to elicit potent immunity to reinfection. The DeltaUP knockout strain was replication competent and virulent. In contrast, the DeltaOMPDC and DeltaOMPDC DeltaUP strains were uracil auxotrophs that rapidly lost their viability during pyrimidine starvation. Replication of the DeltaOMPDC strain but not the DeltaOMPDC DeltaUP strain was also partially rescued in vitro with uridine or cytidine supplementation. Compared to their hypervirulent parental type I strain, the DeltaOMPDC and DeltaOMPDC DeltaUP knockout strains exhibited extreme attenuation in murine virulence (approximately 8 logs). Genetic complementation of the DeltaOMPDC strain using a functional OMPDC allele restored normal replication and type I parental strain virulence phenotypes. A single immunization of mice with either the live critically attenuated DeltaOMPDC strain or the DeltaOMPDC DeltaUP knockout strain effectively induced potent protective immunity to lethal challenge infection. The avirulent nonreverting DeltaOMPDC and DeltaOMPDC DeltaUP strains provide new tools for the dissection of the host response to infection and are promising candidates for safe and effective Th1 vaccine platforms that can be easily genetically engineered. PMID:20605980

  20. 21 CFR 528.1070 - Bc6 recombinant deoxyribonucleic acid construct.

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Bc6 recombinant deoxyribonucleic acid construct... ANIMALS § 528.1070 Bc6 recombinant deoxyribonucleic acid construct. (a) Specifications and indications for use. Five copies of a human Bc6 recombinant deoxyribonucleic acid (rDNA) construct located at the...

  1. Effectiveness of a constructed wetland for acid mine drainage reclamation

    Acid mine drainage (AMD) from an abandoned coal mine in southcentral Kentucky had pH levels as low as 2.5 and iron concentrations as high as 630 mg/L. In the summer of 1992, the SCS constructed a wetland system to treat the AMD that involved use of both physical and biological treatment. The AMD was fed into three anoxic limestone beds, followed by an aeration pond, before entering a series of four cattail cells and a polishing pond. Flow of AMD was initiated in the fall of 1992, and chemical and biological monitoring were conducted throughout the winter months. Chemical analysis of the water along the flow path of the AMD during the first six months of operation indicated that the limestone beds improved the pH substantially, and that most of the metals were removed prior to the water entering the cattail cells. The effectiveness of the wetland system to improve water quality also was monitored using the cladoceran (Ceriodaphnia dubia) survival and reproduction test. Determination of toxic levels indicated a substantial improvement in water quality below the limestone beds, and a slight decrease in toxicity throughout the cattail cells. However, toxic levels stayed the same or increased in the polishing pond. Water quality monitoring will continue through the growing season of 1993 to assess the impact of plant growth on the reclamation of the AMD

  2. Design and construction of a whole cell bacterial 4-hydroxyphenylacetic acid and 2-phenylacetic acid bioassay

    Seppe eDierckx

    2015-06-01

    Full Text Available IntroductionAuxins are hormones that regulate plant growth and development. To accurately quantify the low levels of auxins present in plant and soil samples, sensitive detection methods are needed. In this study, the design and construction of two different whole cell auxin biosensors is illustrated. Both use the auxin responsive element HpaA as an input module and differ in output module. The first biosensor is combined with the gfp gene to produce a fluorescent biosensor. Whereas the second one is combined with the genes textit and phzS to produce a pyocyanin producing biosensor whose product can be measured electrochemically.section{Results} The fluorescent biosensor is able to detect 4-hydroxyphenylacetic acid (4-HPA and 2-phenylacetic acid (PAA concentrations from 15 µM to 3 mM in a dose-responsive manner. The pyocyanin producing biosensor is able to detect 4-HPA concentrations from 1.9 µM to 15.625 µM and PAA concentrations from 15.625 µM to 125 µM, both in a dose-responsive manner.ConclusionsA fluorescent whole cell auxin biosensor and an electrochemical whole cell auxin biosensor have been constructed and tested. Both are able to detect 4-HPA and PAA concentrations that are environmentally relevant in respect to plant growth.

  3. Avirulent Uracil Auxotrophs Based on Disruption of Orotidine-5′-Monophosphate Decarboxylase Elicit Protective Immunity to Toxoplasma gondii ▿ †

    Fox, Barbara A.; Bzik, David J.

    2010-01-01

    The orotidine-5′-monophosphate decarboxylase (OMPDC) gene, encoding the final enzyme of the de novo pyrimidine biosynthesis pathway, was deleted using Toxoplasma gondii KU80 knockouts to develop an avirulent nonreverting pyrimidine auxotroph strain. Additionally, to functionally address the role of the pyrimidine salvage pathway, the uridine phosphorylase (UP) salvage activity was knocked out and a double knockout of UP and OMPDC was also constructed. The nonreverting ΔOMPDC, ΔUP, and ΔOMPDC ΔUP knockout strains were evaluated for pyrimidine auxotrophy, for attenuation of virulence, and for their ability to elicit potent immunity to reinfection. The ΔUP knockout strain was replication competent and virulent. In contrast, the ΔOMPDC and ΔOMPDC ΔUP strains were uracil auxotrophs that rapidly lost their viability during pyrimidine starvation. Replication of the ΔOMPDC strain but not the ΔOMPDC ΔUP strain was also partially rescued in vitro with uridine or cytidine supplementation. Compared to their hypervirulent parental type I strain, the ΔOMPDC and ΔOMPDC ΔUP knockout strains exhibited extreme attenuation in murine virulence (∼8 logs). Genetic complementation of the ΔOMPDC strain using a functional OMPDC allele restored normal replication and type I parental strain virulence phenotypes. A single immunization of mice with either the live critically attenuated ΔOMPDC strain or the ΔOMPDC ΔUP knockout strain effectively induced potent protective immunity to lethal challenge infection. The avirulent nonreverting ΔOMPDC and ΔOMPDC ΔUP strains provide new tools for the dissection of the host response to infection and are promising candidates for safe and effective Th1 vaccine platforms that can be easily genetically engineered. PMID:20605980

  4. Construction of a stainless steel storage tank for phosphoric acid

    Buh, Igor

    2006-01-01

    The main purpose of this thesis was to get acquainted with all necessary procedures for steel storage tank manufacturing and assembly control. The representative storage tank was built from stainless steel and it was designed to hold 750 m3 of phosphoric acid. In the first section all legally mandatory control procedures are described and they are applied to our storage tank in the second section. Welding control is presented, which consists of destructive and non-destructive inspections of t...

  5. Feasibility of biohydrogen production from tofu wastewater with glutamine auxotrophic mutant of Rhodobacter sphaeroides

    Zheng, G.H.; Wang, L.; Kang, Z.H. [School of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping road, Shanghai 200092 (China)

    2010-12-15

    NH{sub 4}{sup +}, which is normally the integrant in organic wastewater, such as Tofu wastewater, is an inhibitor to hydrogen production by anoxygenic phototrophic bacterium. In order to release inhibition of NH{sub 4}{sup +} to biohydrogen generation by Rhodobacter sphaeroides, a glutamine auxotrophic mutant R. sphaeroides TJ-0803 was obtained by mutagenizing with ethyl methane sulfonate. The mutant could generate biohydrogen efficiently in the medium with high NH{sub 4}{sup +} concentration, because the inhibition of NH{sub 4}{sup +} to nitrogenase was released. Under suitable conditions, TJ-0803 could effectively produce biohydrogen from tofu wastewater, which commonly containing 50-60 mg L{sup -1} NH{sub 4}{sup +}, and the generation rate was increased by more than 100% compared with that from wild-type R. sphaeroides. (author)

  6. Construction of a cyanobacterium synthesizing cyclopropane fatty acids.

    Machida, Shuntaro; Shiraiwa, Yoshihiro; Suzuki, Iwane

    2016-09-01

    Microalgae have received much attention as a next-generation source of biomass energy. However, most of the fatty acids (FAs) from microalgae are multiply unsaturated; thus, the biofuels derived from them are fluid, but vulnerable to oxidation. In this study, we attempted to synthesize cyclopropane FAs in the cyanobacterium Synechocystis sp. PCC 6803 by expressing the cfa gene for cyclopropane FA synthase from Escherichia coli with the aim of producing FAs that are fluid and stable in response to oxidization. We successfully synthesized cyclopropane FAs in Synechocystis with a yield of ~30% of total FAs. Growth of the transformants was altered, particularly at low temperatures, but photosynthesis and respiration were not significantly affected. C16:1(∆9) synthesis in the desA(-)/desD(-) strain by expression of the desC2 gene for sn-2 specific ∆9 desaturase positively affected growth at low temperatures via promotion of various cellular processes, with the exceptions of photosynthesis and respiration. Estimation of the apparent activities of desaturases suggested that some acyl-lipid desaturases might recognize the lipid side chain. PMID:27263419

  7. Biohydrogen Production from Tofu Wastewater with Glutamine Auxotrophic Mutant of Rhodobacter sphaeroides

    Zheng, G. H.; Kang, Z. H.; Qian, Y. F.; Wang, L.; Zhou, Q.; Zhu, H. G.

    2008-02-01

    Hydrogen production from organic wastewater by photo-bacteria has been attracted more attention, not only because hydrogen is a clean energy, but also because it can be a process for organic wastewater pre-treatment. However NH4+, which normally is the integrant in organic wastewater, is the inhibitor to hydrogen production with photo-bacteria. In this study, the NH4+ effect on biohydrogen generation and nitrogenase activity of anoxygenic phototrophic bacteria-Rhodobacter sphaeroides was studied. Biohydrogen generation with wild-type R. sphaeroides was found to be more sensitive to NH4+ due to the obvious inhibition of NH4+ to its nitrogenase. For avoiding inhibition of NH4+ to biohydrogen generation of R. sphaeroides, a glutamine auxotrophic mutant R. sphaeroides AR-3 was obtained by EMS treatment. The mutant could generate biohydrogen efficiently in the medium with higher NH4+ concentration. Under suitable conditions, AR-3 produced biohydrogen from tofu wastewater with an average generation rate of 14.2 ml L-1h-1, it was increased by more than 100% compared with that from wild-type R. sphaeroides.

  8. Stimulation of cell proliferation and polyphosphoinositide turnover in a yeast sterol auxotroph by ergosterol

    The effect of ergosterol on cell division and phospholipid metabolism was investigated in strain GL7, a sterol auxotroph of Saccharmyces cerevisiae. When starved for ergosterol GL7 remains viable but grows very slowly and partially accumulates in the unbudded state. The readdition of ergosterol alone or together with cholesterol but not cholesterol alone stimulates both budding and cell proliferation noticeably after a lag of several hours. Within 10 min after ergosterol readdition to prelabeled cholesterol-grown cells the 32P and [3H] inositol content of the polyphosphoinositides increases markedly followed by an equally striking and rapid decrease. The phosphatidylinositol kinase activity in the membrane fraction also increases when cells growing on cholesterol were supplemented with a small amount of ergosterol. A serine specific casein kinase activity which is immunoprecipitable by antibody prepared against the Rous sarcoma virus transforming protein, pp60/sup v-src/, is enhanced in ergosterol-grown cells when compared to the kinase activity in cholesterol cells. Taken together the results suggest that increased poly-phosphoinositide turnover and protein phosphorylation are associated with or parallel the stimulation of cell proliferation by a small amount of the yeast's natural sterol

  9. Corrosion rate of construction materials in hot phosphoric acid with the contribution of anodic polarization

    Kouril, M.; Christensen, Erik; Eriksen, S.;

    2011-01-01

    The paper is focused on selection of a proper material for construction elements of water electrolysers, which make use of a 85% phosphoric acid as an electrolyte at temperature of 150 8C and which might be loaded with anodic polarization up to 2.5 V versus a saturated Ag/AgCl electrode (SSCE......% phosphoric acid at 150 8C and at polarization of 2.5 V/SSCE is tantalum. In that case, even a gentle cathodic polarization is harmful in such an acidic environment. Hydrogen reduction leads to tantalum hydride formation, to loss of mechanical properties and to complete disintegration of the metal. Contrary...... to tantalum, titanium is free of any corrosion resistance in hot phosphoric acid. Its corrosion rate ranges from tens of millimetres to metres per year depending on temperature of the acid. Alloy bonded tantalum coating was recognized as an effective corrosion protection for both titanium and stainless steel...

  10. Bioaccumulation of metals in constructed wetlands used to treat acid drainage

    Constructed wetlands are being used extensively as a potential mitigation for acid drainage. However, removal of metals to meet compliance requirements has varied among wetlands, ranging from partial to total success. In addition, wetlands are sinks for contaminants found in acid drainage, and bioaccumulation of these contaminants to levels that would adversely affect the food web is of growing concern. The primary objective of this project was to determine whether bioaccumulation of metals occurs in wetlands constructed for treatment of acid drainage. Water, sediment, plant and benthos samples were collected from two wetlands constructed by the Tennessee Valley Authority and a natural wetland in the spring and fall of 1992, and metal concentrations were determined. One of the constructed wetlands, Impoundment 1, has generally been in compliance for NPDES; the other, Widow's Creek, has never been in compliance. Preliminary results indicate similarities in sediment and plant metal concentrations between Impoundment 1 and the natural wetland and greater metal concentrations in the sediment and plants at Widow's Creek. Data also indicate that Mn, Zn, Cu, Ni, and Cr are being accumulated in the plants at each wetland. However, accumulation of metals by these plants probably accounts for only a small percentage of the removal of the annual metal load supplied to each wetland. Bioaccumulation of metals in the benthic organisms at each wetland is currently being investigated

  11. Phosphatidylserine biosynthesis in cultured Chinese hamster ovary cells. II. Isolation and characterization of phosphatidylserine auxotrophs

    Chinese hamster ovary (CHO) cell mutants that required exogenously added phosphatidylserine for cell growth were isolated by using the replica technique with polyester cloth, and three such mutants were characterized. Labeling experiments on intact cells with 32Pi and L-[U-14C]serine revealed that a phosphatidylserine auxotroph, designated as PSA-3, was strikingly defective in phosphatidylserine biosynthesis. When cells were grown for 2 days without phosphatidylserine, the phosphatidylserine content of PSA-3 was about one-third of that of the parent. In extracts of the mutant, the enzymatic activity of the base-exchange reaction of phospholipids with serine producing phosphatidylserine was reduced to 33% of that in the parent; in addition, the activities of base-exchange reactions of phospholipids with choline and ethanolamine in the mutant were also reduced to 1 and 45% of those in the parent, respectively. Furthermore, it was demonstrated that the serine-exchange activity in the parent was inhibited approximately 60% when choline was added to the reaction mixture whereas that in the mutant was not significantly affected. From the results presented here, we conclude the following. There are at least two kinds of serine-exchange enzymes in CHO cells; one (serine-exchange enzyme I) can catalyze the base-exchange reactions of phospholipids with serine, choline, and ethanolamine while the other (serine-exchange enzyme II) does not use the choline as a substrate. Serine-exchange enzyme I, in which mutant PSA-3 is defective, plays a major role in phosphatidylserine biosynthesis in CHO cells. Serine-exchange enzyme I is essential for the growth of CHO cells

  12. The use of constructed wetlands in the treatment of acid mine drainage

    US government regulations require that all effluents from industrial operations, including mining, meet certain water quality standards. Constructed wetlands have proven to be useful in helping to attain those standards. Application of this biotechnology to mine water drainage can reduce water treatment costs and improve water quality in streams and rivers adversely affected by acidic mine water drainage from abandoned mines. Over 400 constructed wetland water treatment systems have been built on mined lands largely as a result of research by the US Bureau of Mines. Wetlands are passive biological treatment systems that are relatively inexpensive to construct and require minimal maintenance. Chemical treatment costs are reduced sufficiently to repay the cost of construction in less than a year. The mine waste water is typically treated in a series of excavated ponds that resemble small marsh areas. The ponds are engineered to facilitate bacterial oxidation of iron. Ideally, the water then flows through a composted organic substrate supporting a population of sulphate-reducing bacteria which raises the pH. Constructed wetlands in the USA are described - their history, functions, construction methodologies, applicabilities, limitations and costs. (author). 26 refs, 2 figs

  13. Embedding methods for poly(L-lactic acid) microfiber mesh/human mesenchymal stem cell constructs.

    D'Alessandro, D; Battolla, B; Trombi, L; Barachini, S; Cascone, M G; Bernardini, N; Petrini, M; Mattii, L

    2009-01-01

    Fiber mesh scaffolds were recently investigated in tissue engineering as possible support for stem cell growth and differentiation, in order to repair lesion areas in clinical practice. In particular, the literature is focused on fiber mesh scaffolds constituted of biocompatible and resorbable polymeric structures, like poly(L-lactic acid) (PLLA). However, as regards the study of constructs constituted of PLLA microfibers and cells, only quantitative and SEM analyses were reported, lacking histological analysis. Histological evaluation of these constructs could give important information about cellular distribution in the scaffold, cell-scaffold interactions and extracellular matrix production. The purpose of our study was to find a valid method to analyze PLLA microfiber/cell constructs from both histological and histochemical angles. Biodegradable non-woven fiber meshes were prepared using hollow microfibers, based on PLLA. We first evaluated different embedding methods useable for histological analysis and the results showed that among the paraffin, Killik, and acrylic resin the only suitable medium was the latter. Then we employed the acrylic resin to embed the constructs made up of PLLA microfibers and bone marrow-derived human mesenchymal stromal cells, which we then analyzed with Toluidine Blue, PAS and Alcian Blue staining. These constructs, previously analyzed for cell viability by MTT and CCK-8 tests, showed viable/proliferating cells until 6 weeks of culture. The stainings performed on constructs confirmed viability data obtained with SEM and MTT/CCK-8 and supplied other information on the cell behaviors such as the distribution and organization onto the scaffold and the production of extracellular matrix molecules. In conclusion, this methodological study mainly suggests a suitable method to analyze PLLA microfiber/cell constructs, at the same time confirming and enriching the literature data on the compatibility between PLLA microfibers and hMSCs. PMID

  14. Genetic and biochemical characterization of a mutation (fatA) that allows trans unsaturated fatty acids to replace the essential cis unsaturated fatty acids of Escherichia coli.

    DeVeaux, L C; Cronan, J E; Smith, T L

    1989-01-01

    Unsaturated fatty acid auxotrophs of Escherichia coli are able to use only unsaturated fatty acids of the cis configuration as the required growth supplement. A mutation in the fatA gene allows such auxotrophs to utilize unsaturated fatty acids with a trans double bond as well as fatty acids having a cis double bond. The fatA gene was mapped to min 69 near argG, and the allele studied (fatA1) was found to be dominant over the wild-type gene. fatA1 mutant strains grew at similar rates when sup...

  15. Supramolecular Coordination Assemblies Constructed From Multifunctional Azole-Containing Carboxylic Acids

    Yuheng Deng

    2010-05-01

    Full Text Available This paper provides a brief review of recent progress in the field of metal coordination polymers assembled from azole-containing carboxylic acids and gives a diagrammatic summary of the diversity of topological structures in the resulting infinite metal-organic coordination networks (MOCNs. Azole-containing carboxylic acids are a favorable kind of multifunctional ligand to construct various metal complexes with isolated complexes and one, two and three dimensional structures, whose isolated complexes are not the focus of this review. An insight into the topology patterns of the infinite coordination polymers is provided. Analyzed topologies are compared with documented topologies and catalogued by the nature of nodes and connectivity pattern. New topologies which are not available from current topology databases are described and demonstrated graphically.

  16. Screening a wide host-range, waste-water metagenomic library in tryptophan auxotrophs of Rhizobium leguminosarum and of Escherichia coli reveals different classes of cloned trp genes.

    Li, Youguo; Wexler, Margaret; Richardson, David J; Bond, Philip L; Johnston, Andrew W B

    2005-12-01

    A metagenomic cosmid library was constructed, in which the insert DNA was derived from bacteria in a waste-water treatment plant and the vector was the wide host-range cosmid pLAFR3. The library was screened for clones that could correct defined tryptophan auxotrophs of the alpha-proteobacterium Rhizobium leguminosarum and of Escherichia coli. A total of 26 different cosmids that corrected at least one trp mutant in one or both of these species were obtained. Several cosmids corrected the auxotrophy of one or more R. leguminosarum trp mutants, but not the corresponding mutants in E. coli. Conversely, one cosmid corrected trpA, B, C, D and E mutants of E. coli but none of the trp mutants of R. leguminosarum. Two of the Trp+ cosmids were examined in more detail. One contained a trp operon that resembled that of the pathogen Chlamydophila caviae, containing the unusual kynU gene, which specifies kynureninase. The other, whose trp genes functioned in R. leguminosarum but not in E. coli, contained trpDCFBA in an operon that is likely co-transcribed with five other genes, most of which had no known link with tryptophan synthesis. The sequences of these TRP proteins, and the products of nine other genes encoded by this cosmid, failed to affiliate them with any known bacterial lineage. For one metagenomic cosmid, lac reporter fusions confirmed that its cloned trp genes were transcribed in R. leguminosarum, but not in E. coli. Thus, rhizobia, with their many sigma-factors, may be well-suited hosts for metagenomic libraries, cloned in wide host-range vectors. PMID:16309391

  17. Construction of HA-1-DC Nucleic-acid Vaccine and Induction of Specific Cytotoxic T Lymphocytes

    WANG Yaya; ZHANG Donghua; HU Jinmei; LIU Wenli; ZHOU hongsheng; ZHANG Lu; LIU Dan; HUANG Zhenqian; TAN Huo

    2007-01-01

    An HA-1-DC nucleic-acid vaccine was constructed to induce anti-leukemia effect after hematopoietic stem cell transplantation (HSCT). DCs were generated from HSCT donors in vitro, and its immunologic activity was assayed by using flow cytometry and mixed lymphocytes reaction.HA-1 gene was electroporated into the cultured DCs to construct a DC nucleic-acid vaccine. After transfection for 48 h, the expression of HA-1 protein could be detected by using Western blot. The DCs were cultured with syngenic lymphocytes to induce specific cytotoxic T lymphocytes (CTLs).The cytoxicity of the CTLs was detected by LDH assay. The results showed that The DCs derived from peripheral blood monocytes (PBMCs) expressed the phenotype of DCs, and were effective in stimulating proliferation of the allogenic lymphocytes. After electroporating for 48-h, HA-1 protein was detected by using Western blot. The cytotoxity of inducing CTLs was higher than the control group. It was suggested that minor histocompatibility antigen HA-1 could be considered as a target of immunotherapy against leukemia after HSCT.

  18. Synthesis, crystal structure and optical property of three coordination polymer constructed from m-phenylenediacrylate acid

    Xiao, YiFan; Wang, TingTing; Zeng, HePing, E-mail: hpzeng@scut.edu.cn

    2015-01-15

    Three new complexes of the wholly deprotonated flexible ligand m-phenylenediacrylate acid (H{sub 2}mpda), namely, [Zn (mpda) (H{sub 2}O)] [1], [Pr{sub 2}(mpda){sub 2}(H{sub 2}O){sub 2}(CHOO){sub 2}] [2], and [Mn{sub 2}(mpda){sub 2} (H{sub 2}O){sub 4}] [3], were synthesized by the solvothermal reaction. The complexes were characterized by IR spectroscopy, thermogravimetric analysis, and X-ray single-crystal diffraction. A mixed sample [Nd(mpda)(H{sub 2}O)(CHOO)·Pr(mpda)(H{sub 2}O)(CHOO)] [2{sup ]} was also synthesized and studied. Compounds [1] and [2] exhibit a selective sensing function with respect to acetone, and they are a potential luminescent sensory material for the selective detection of Zn{sup 2+} and Ni{sup 2+} ions, respectively. Furthermore, the fluorescent changes of compound [1] upon the addition of cations (Fe{sup 3+} and Zn{sup 2+}, Bi{sup 2+} and Zn{sup 2+}) are utilized to construct two logic gates at the molecular level. - Graphical abstract: Three new complexes of flexible ligand m-phenylenedicarboxylic acid were synthesized by solvothermal reaction. Three metal−organic frameworks exhibiting 1D, 2D, 3D structures, respectively. - Highlights: • Three new complexes of m-phenylenedicarboxylic acid were synthesized. • Three metal−organic frameworks exhibiting 1D, 2D, 3D structures, respectively. • [1] and [2] exhibits a very high quenching effect with acetone. • [1] and [2] are a potential luminescent sensory material for Zn{sup 2+}, Ni{sup 2+} ions. • Two logic gates have been constructed using compound [1].

  19. Ethanol production from acid hydrolysates based on the construction and demolition wood waste using Pichia stipitis.

    Cho, Dae Haeng; Shin, Soo-Jeong; Bae, Yangwon; Park, Chulhwan; Kim, Yong Hwan

    2011-03-01

    The feasibility of ethanol production from the construction and demolition (C&D) wood waste acid hydrolysates was investigated. The chemical compositions of the classified C&D wood waste were analyzed. Concentrated sulfuric acid hydrolysis was used to obtain the saccharide hydrolysates and the inhibitors in the hydrolysates were also analyzed. The C&D wood waste composed of lumber, plywood, particleboard, and medium density fiberboard (MDF) had polysaccharide (cellulose, xylan, and glucomannan) fractions of 60.7-67.9%. The sugar composition (glucose, xylose, and mannose) of the C&D wood wastes varied according to the type of wood. The additives used in the wood processing did not appear to be released into the saccharide solution under acid hydrolysis. Although some fermentation inhibitors were detected in the hydrolysates, they did not affect the ethanol production by Pichia stipitis. The hexose sugar-based ethanol yield and ethanol yield efficiency were 0.42-0.46 g ethanol/g substrate and 84.7-90.7%, respectively. Therefore, the C&D wood wastes dumped in landfill sites could be used as a raw material feedstock for the production of bioethanol. PMID:21251816

  20. Secretion of Rhoptry and Dense Granule Effector Proteins by Nonreplicating Toxoplasma gondii Uracil Auxotrophs Controls the Development of Antitumor Immunity.

    Fox, Barbara A; Sanders, Kiah L; Rommereim, Leah M; Guevara, Rebekah B; Bzik, David J

    2016-07-01

    Nonreplicating type I uracil auxotrophic mutants of Toxoplasma gondii possess a potent ability to activate therapeutic immunity to established solid tumors by reversing immune suppression in the tumor microenvironment. Here we engineered targeted deletions of parasite secreted effector proteins using a genetically tractable Δku80 vaccine strain to show that the secretion of specific rhoptry (ROP) and dense granule (GRA) proteins by uracil auxotrophic mutants of T. gondii in conjunction with host cell invasion activates antitumor immunity through host responses involving CD8α+ dendritic cells, the IL-12/interferon-gamma (IFN-γ) TH1 axis, as well as CD4+ and CD8+ T cells. Deletion of parasitophorous vacuole membrane (PVM) associated proteins ROP5, ROP17, ROP18, ROP35 or ROP38, intravacuolar network associated dense granule proteins GRA2 or GRA12, and GRA24 which traffics past the PVM to the host cell nucleus severely abrogated the antitumor response. In contrast, deletion of other secreted effector molecules such as GRA15, GRA16, or ROP16 that manipulate host cell signaling and transcriptional pathways, or deletion of PVM associated ROP21 or GRA3 molecules did not affect the antitumor activity. Association of ROP18 with the PVM was found to be essential for the development of the antitumor responses. Surprisingly, the ROP18 kinase activity required for resistance to IFN-γ activated host innate immunity related GTPases and virulence was not essential for the antitumor response. These data show that PVM functions of parasite secreted effector molecules, including ROP18, manipulate host cell responses through ROP18 kinase virulence independent mechanisms to activate potent antitumor responses. Our results demonstrate that PVM associated rhoptry effector proteins secreted prior to host cell invasion and dense granule effector proteins localized to the intravacuolar network and host nucleus that are secreted after host cell invasion coordinately control the

  1. Construction of hybrid cell with Phanerochaete chrysosporium todegrade terephthalic acid wastewater (I) phenotype evidence

    2000-01-01

    The fungi Phanerochaete chrysosporium (PC) and Saccharomyces cerevisiae Y99 and the native bacterium YZ1 were the three parental strains for construction of hybrid cells through protoplast fusion to degrade terephthalic acid (TPA) wastewater. The results showed that the native bacterium YZ1 protoplasm could integrate with that of PC to form the hybrid cell Fhh and the fungus Y99 protoplasm also could integrate with that of Fhh to form the hybrid cell Fhhh. The protoplasts of YZ1 and Y99 could change the morphology of PC spore and mycelinm for two times. The hybrid cell Fhhh got the best growth and degradation abilities in the wastewater. It suggested that the hybrid strains obtained from the inter-kingdom protoplast fusion of the three parental strains could create potential for the purification of TPA wastewater.

  2. Extended safety and efficacy studies of a live attenuated double leucine and pantothenate auxotroph of Mycobacterium tuberculosis as a vaccine candidate

    Sampson, Samantha L.; Mansfield, Keith G; Carville, Angela; Magee, D Mitchell; Quitugua, Teresa; Howerth, Elizabeth W.; Bloom, Barry R.; Hondalus, Mary K.

    2011-01-01

    We have previously described the development of a live, fully attenuated Mycobacterium tuberculosis (Mtb) vaccine candidate strain with two independent attenuating auxotrophic mutations in leucine and pantothenate biosynthesis. In the present work, those studies have been extended to include testing for protective efficacy in a long-term guinea pig survival model and safety testing in the highly tuberculosis susceptible Rhesus macaque. To model the safety of the ΔleuD ΔpanCD strain in HIV-inf...

  3. Predicting Three-Dimensional Conformations of Peptides Constructed of Only Glycine, Alanine, Aspartic Acid, and Valine

    Oda, Akifumi; Fukuyoshi, Shuichi

    2015-06-01

    The GADV hypothesis is a form of the protein world hypothesis, which suggests that life originated from proteins (Lacey et al. 1999; Ikehara 2002; Andras 2006). In the GADV hypothesis, life is thought to have originated from primitive proteins constructed of only glycine, alanine, aspartic acid, and valine ([GADV]-proteins). In this study, the three-dimensional (3D) conformations of randomly generated short [GADV]-peptides were computationally investigated using replica-exchange molecular dynamics (REMD) simulations (Sugita and Okamoto 1999). Because the peptides used in this study consisted of only 20 residues each, they could not form certain 3D structures. However, the conformational tendencies of the peptides were elucidated by analyzing the conformational ensembles generated by REMD simulations. The results indicate that secondary structures can be formed in several randomly generated [GADV]-peptides. A long helical structure was found in one of the hydrophobic peptides, supporting the conjecture of the GADV hypothesis that many peptides aggregated to form peptide multimers with enzymatic activity in the primordial soup. In addition, these results indicate that REMD simulations can be used for the structural investigation of short peptides.

  4. Construction of the Core of Pseudolaric Acid A and Mechanistic Studies on Intramolecular [4+3] Cycloaddition

    2001-01-01

    This paper describes the construction of hemiacetal 2, the core of pseudolaric acid A via oxidative cleavage of acetonide 6 or 7 and enolization-hemiacetalization of aldehyde 8. A plausible general mechanism for the intramolecular [4+3] cycloaddition of sulfoxide 4 to adduct 3 is suggested.

  5. Synthesis of nucleoside and nucleotide conjugates of bile acids, and polymerase construction of bile acid-functionalized DNA.

    Ikonen, Satu; Macícková-Cahová, Hana; Pohl, Radek; Sanda, Miloslav; Hocek, Michal

    2010-03-01

    Aqueous Sonogashira cross-coupling reactions of 5-iodopyrimidine or 7-iodo-7-deazaadenine nucleosides with bile acid-derived terminal acetylenes linked via an ester or amide tether gave the corresponding bile acid-nucleoside conjugates. Analogous reactions of halogenated nucleoside triphosphates gave directly bile acid-modified dNTPs. Enzymatic incorporation of these modified nucleotides to DNA was successfully performed using Phusion polymerase for primer extension. One of the dNTPs (dCTP bearing cholic acid) was also efficient for PCR amplification. PMID:20165813

  6. Production of L-threonine by auxotrophs and analogue resistant mutants of Escherichia coli

    A threonine overproducer, E. coli TF427, which is resistant to threonine analogue, α-amino-β-hydroxyvaleric acid (AHV), and requires both methionine and isoleucine was developed by the mutations of E. coli W3110 using N-methyl-N'-nitro-N-nitrosoguanidine (NTG) and UV. The E. coli TF427 produced 46.5 g/l of threonine in a 5-L jar fermentor after 44 hr cultivation. The aspartokinase I of TF427 was not inhibited by threonine, and its synthesis was not repressed by threonine plus isoleucine

  7. Use of submitochondrial particle (SMP) assays for assessing wetlands constructed for sequestering acid mine runoff

    Use of constructed wetlands to sequester metals from acid mine drainage is part of a USEPA SITE demonstration at Burleigh Tunnel near Silverplume, Colorado. Samples are collected on a seasonal basis for toxicity evaluation of two different pilot treatment systems. Water samples were obtained from the outflow of two experimental wetland cells utilizing either upflow and downflow treatment, as well as upstream and downstream of the discharge of Burleigh Tunnel to Clear Creek. Submitochondrial Particle (SMP), Ceriodaphnia dubia and Pimephales promelas acute bioassays were used to evaluate the water quality. The SMP bioassay is based on the electron transfer complex derived from mitochondria. Toxic responses result from subcellular perturbations of various subsets of enzyme systems contained in the complex. In prior work, a 0.79 r2 was reported between the SMP bioassay and P. promelas for 11 inorganics on the EPA Priority Pollutant list. The SMP bioassay provided data consistent with the whole organism results. The two most toxic samples: the Burleigh outflow, and the Clear Creek Upstream sample, gave C. dubia LC50s of 1.01% and 8.41%, respectively. The Burleigh outflow P. promelas LC50 was 1.55%. SMP EC50s for the Burleigh outflow and the Clear Creek Upstream sample were 0.63% and 1.63%, respectively. As the SMP bioassay requires 1 hour to run and costs approximately 1/10th of whole organism assays, it was feasible to determine EC50 values for 7 samples vs. the two sample LC50s determined using whole organism assays. The SMP bioassays can provide sufficient sampling density, at low cost, allowing effective delineation of wetland performance over time

  8. Transferability of different classical force fields for right and left handed α-helices constructed from enantiomeric amino acids.

    Biswas, Santu; Sarkar, Sujit; Pandey, Prithvi Raj; Roy, Sudip

    2016-02-21

    Amino acids can form d and l enantiomers, of which the l enantiomer is abundant in nature. The naturally occurring l enantiomer has a greater preference for a right handed helical conformation, and the d enantiomer for a left handed helical conformation. The other conformations, that is, left handed helical conformations of the l enantiomers and right handed helical conformations of the d enantiomers, are not common. The energetic differences between left and right handed alpha helical peptide chains constructed from enantiomeric amino acids are investigated using quantum chemical calculations (using the M06/6-311g(d,p) level of theory). Further, the performances of commonly used biomolecular force fields (OPLS/AA, CHARMM27/CMAP and AMBER) to represent the different helical conformations (left and right handed) constructed from enantiomeric (D and L) amino acids are evaluated. 5- and 10-mer chains from d and l enantiomers of alanine, leucine, lysine, and glutamic acid, in right and left handed helical conformations, are considered in the study. Thus, in total, 32 α-helical polypeptides (4 amino acids × 4 conformations of 5-mer and 10-mer) are studied. Conclusions, with regards to the performance of the force fields, are derived keeping the quantum optimized geometry as the benchmark, and on the basis of phi and psi angle calculations, hydrogen bond analysis, and different long range helical order parameters. PMID:26863595

  9. Lipophilic nucleic acids--a flexible construction kit for organization and functionalization of surfaces.

    Schade, Matthias; Berti, Debora; Huster, Daniel; Herrmann, Andreas; Arbuzova, Anna

    2014-06-01

    Lipophilic nucleic acids have become a versatile tool for structuring and functionalization of lipid bilayers and biological membranes as well as cargo vehicles to transport and deliver bioactive compounds, like interference RNA, into cells by taking advantage of reversible hybridization with complementary strands. This contribution reviews the different types of conjugates of lipophilic nucleic acids, and their physicochemical and self-assembly properties. Strategies for choosing a nucleic acid, lipophilic modification, and linker are discussed. Interaction with lipid membranes and its stability, dynamic structure and assembly of lipophilic nucleic acids upon embedding into biological membranes are specific points of the review. A large diversity of conjugates including lipophilic peptide nucleic acid and siRNA provides tailored solutions for specific applications in bio- and nanotechnology as well as in cell biology and medicine, as illustrated through some selected examples. PMID:24650567

  10. Role of dissimilatory sulfate reduction in wetlands constructed for acid coal mine drainage (AMD) treatment. Master's thesis

    Five constructed wetlands with different organic substrates were exposed to the same quantity/quality of acid mine drainage (AMD). During the 16-month exposure to AMD, all wetlands accumulated S in the forms of organic and reduced inorganic S and Fe in the form of iron sulfides. Iron sulfide and probably most of the organic S(C-bonded S) accumulation were end products of bacterial dissimilatory sulfate reduction. Results of study support the notion that sulfate reduction and accumulation of Fe sulfides contribute to Fe retention in wetlands exposed to AMD. Detailed information is provided

  11. Recoded organisms engineered to depend on synthetic amino acids.

    Rovner, Alexis J; Haimovich, Adrian D; Katz, Spencer R; Li, Zhe; Grome, Michael W; Gassaway, Brandon M; Amiram, Miriam; Patel, Jaymin R; Gallagher, Ryan R; Rinehart, Jesse; Isaacs, Farren J

    2015-02-01

    Genetically modified organisms (GMOs) are increasingly used in research and industrial systems to produce high-value pharmaceuticals, fuels and chemicals. Genetic isolation and intrinsic biocontainment would provide essential biosafety measures to secure these closed systems and enable safe applications of GMOs in open systems, which include bioremediation and probiotics. Although safeguards have been designed to control cell growth by essential gene regulation, inducible toxin switches and engineered auxotrophies, these approaches are compromised by cross-feeding of essential metabolites, leaked expression of essential genes, or genetic mutations. Here we describe the construction of a series of genomically recoded organisms (GROs) whose growth is restricted by the expression of multiple essential genes that depend on exogenously supplied synthetic amino acids (sAAs). We introduced a Methanocaldococcus jannaschii tRNA:aminoacyl-tRNA synthetase pair into the chromosome of a GRO derived from Escherichia coli that lacks all TAG codons and release factor 1, endowing this organism with the orthogonal translational components to convert TAG into a dedicated sense codon for sAAs. Using multiplex automated genome engineering, we introduced in-frame TAG codons into 22 essential genes, linking their expression to the incorporation of synthetic phenylalanine-derived amino acids. Of the 60 sAA-dependent variants isolated, a notable strain harbouring three TAG codons in conserved functional residues of MurG, DnaA and SerS and containing targeted tRNA deletions maintained robust growth and exhibited undetectable escape frequencies upon culturing ∼10(11) cells on solid media for 7 days or in liquid media for 20 days. This is a significant improvement over existing biocontainment approaches. We constructed synthetic auxotrophs dependent on sAAs that were not rescued by cross-feeding in environmental growth assays. These auxotrophic GROs possess alternative genetic codes that

  12. Research on the Construction of Tissue Engineering Scaffolds by Alginate-hyaluronic Acid with Different Characteristics

    LI Qin-hua; LIU Li; LIN Dong-qing

    2014-01-01

    This research uses alginate and hyaluronic acid as the main component to prepare support, then explores the possibilities as a tissue engineering scaffold. Firstly, prepare HA with various average molecular weight and alginate with different viscosity, mix them up at a certain proportion and make it into a AlgCa 2+-HA composite scaffold with a film-forming method. This article discusses the feasibility of this scaffold used in tissue engineering field according to the consequence of moisture content testing, mechanical analysis, and scanning electron microscopy analysis. The structure and properties of AlgCa2+-HA composite scaffold are closely related to some factors such as average molecular weight of hyaluronic acid, hyaluronic acid concentration, alginate viscosity, cross-linking agents and processing technology. The AlgCa 2+-HA composite material, which is at different proportions and adding different cross-linking agent,has some certain characteristics:moisture content ranging from 50%to 95%, tensile strength between 2.69 N/mm2 and 4.299 N/mm2, and elongation at break is about 58%to 160%. The prepared AlgCa2+-HA composite scaffolds can be used as tissue engineering scaffolds resulting from its high moisture content, good mechanical properties and ideal pore structure.

  13. Synthesis, structures and properties of two new chiral rare earth-organic frameworks constructed by L/D-tartaric acid

    Hu, Gonghao; Zhang, Haitao; Miao, Hao; Wang, Jiahong [College of Chemistry and Chemical Engineering, State Key Laboratory of Materials-oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009 (China); Xu, Yan, E-mail: yanxu@njtech.edu.cn [College of Chemistry and Chemical Engineering, State Key Laboratory of Materials-oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009 (China); State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093 (China)

    2015-09-15

    Hydrothermal reactions of rare earth cerium with L- or D- tartaric acid afford a pair of novel chiral enantiomer coordination polymers, namely, [Ce(L-tart)(CH{sub 2}OHCH{sub 2}OH)(H{sub 2}O)]Cl (L-1) and [Ce(D-tart)(CH{sub 2}OHCH{sub 2}OH)(H{sub 2}O)]Cl (D-1). Their structures were determined by single crystal X-ray diffraction analyses and further characterized by elemental analyses, XRD, IR spectra, and TG analyses. The circular dichroism (CD) spectra and second-harmonic generation (SHG) efficiency measurements proved that they are of structural chirality in the bulk samples. To the best of our knowledge, the enantiomers of L-1 and D-1 are the first 2D chiral dilayer frameworks constructed from L/D-tartrate ligands, ancillary ligand ethanediol and lanthanide ion Ce. - Graphical abstract: Hydrothermal reactions of rare earth cerium with L- or D- tartaric acid afford a pair of novel chiral enantiomer coordination polymers, namely, [Ce(L-tart)(CH{sub 2}OHCH{sub 2}OH)(H{sub 2}O)]Cl (L-1) and [Ce(D-tart)(CH{sub 2}OHCH{sub 2}OH)(H{sub 2}O)]Cl (D-1). Structural analysis indicates that the enantiomers of L-1 and D-1 are the first 2D chiral dilayer frameworks constructed from L/D-tartrate ligands and ancillary ligands ethanediol reacted with lanthanide ions Ce.

  14. Synthesis, structures and properties of two new chiral rare earth-organic frameworks constructed by L/D-tartaric acid

    Hydrothermal reactions of rare earth cerium with L- or D- tartaric acid afford a pair of novel chiral enantiomer coordination polymers, namely, [Ce(L-tart)(CH2OHCH2OH)(H2O)]Cl (L-1) and [Ce(D-tart)(CH2OHCH2OH)(H2O)]Cl (D-1). Their structures were determined by single crystal X-ray diffraction analyses and further characterized by elemental analyses, XRD, IR spectra, and TG analyses. The circular dichroism (CD) spectra and second-harmonic generation (SHG) efficiency measurements proved that they are of structural chirality in the bulk samples. To the best of our knowledge, the enantiomers of L-1 and D-1 are the first 2D chiral dilayer frameworks constructed from L/D-tartrate ligands, ancillary ligand ethanediol and lanthanide ion Ce. - Graphical abstract: Hydrothermal reactions of rare earth cerium with L- or D- tartaric acid afford a pair of novel chiral enantiomer coordination polymers, namely, [Ce(L-tart)(CH2OHCH2OH)(H2O)]Cl (L-1) and [Ce(D-tart)(CH2OHCH2OH)(H2O)]Cl (D-1). Structural analysis indicates that the enantiomers of L-1 and D-1 are the first 2D chiral dilayer frameworks constructed from L/D-tartrate ligands and ancillary ligands ethanediol reacted with lanthanide ions Ce.

  15. Adsorption compared with sulfide precipitation as metal removal processes from acid mine drainage in a constructed wetland

    Machemer, Steven D.; Wildeman, Thomas R.

    1992-01-01

    Metal removal processes from acid mine drainage were studied in an experimental constructed wetland in the Idaho Springs-Central City mining district of Colorado. The wetland was designed to passively remove heavy metals from the mine drainage flowing from the Big Five Tunnel. Concurrent studies were performed in the field on the waters flowing from the wetland and in the laboratory on the wetland substrate. Both studies suggest that there is competition for organic adsorption sites among Fe, Cu, Zn and Mn. Iron and Cu appear to be more strongly adsorbed than Zn and Mn. The adsorption of metals varies with the fluctuation of pH in the outflow water. Also indicated by field and laboratory studies is the microbial reduction of sulfate with a corresponding increase in the sulfide concentration of the water. As sulfide is generated. Cu and Zn are completely removed. The field results suggest that upon start up of a constructed wetland, the adsorption of dissolved metals onto organic sites in the substrate material will be an important process. Over time, sulfide precipitation becomes the dominant process for metal removal from acid mine drainage.

  16. Performance of the auxotrophic Saccharomyces cerevisiae BY4741 as host for the production of IL-1β in aerated fed-batch reactor: role of ACA supplementation, strain viability, and maintenance energy

    Zueco Jesus

    2009-12-01

    Full Text Available Abstract Background Saccharomyces cerevisiae BY4741 is an auxotrophic commonly used strain. In this work it has been used as host for the expression and secretion of human interleukin-1β (IL1β, using the cell wall protein Pir4 as fusion partner. To achieve high cell density and, consequently, high product yield, BY4741 [PIR4-IL1β] was cultured in an aerated fed-batch reactor, using a defined mineral medium supplemented with casamino acids as ACA (auxotrophy-complementing amino acid source. Also the S. cerevisiae mutant BY4741 Δyca1 [PIR4-IL1β], carrying the deletion of the YCA1 gene coding for a caspase-like protein involved in the apoptotic response, was cultured in aerated fed-batch reactor and compared to the parental strain, to test the effect of this mutation on strain robustness. Viability of the producer strains was examined during the runs and a mathematical model, which took into consideration the viable biomass present in the reactor and the glucose consumption for both growth and maintenance, was developed to describe and explain the time-course evolution of the process for both, the BY4741 parental and the BY4741 Δyca1 mutant strain. Results Our results show that the concentrations of ACA in the feeding solution, corresponding to those routinely used in the literature, are limiting for the growth of S. cerevisiae BY4741 [PIR4-IL1β] in fed-batch reactor. Even in the presence of a proper ACA supplementation, S. cerevisiae BY4741 [PIR4-IL1β] did not achieve a high cell density. The Δyca1 deletion did not have a beneficial effect on the overall performance of the strain, but it had a clear effect on its viability, which was not impaired during fed-batch operations, as shown by the kd value (0.0045 h-1, negligible if compared to that of the parental strain (0.028 h-1. However, independently of their robustness, both the parental and the Δyca1 mutant ceased to grow early during fed-batch runs, both strains using most of the

  17. A novel nanofiber Cur-loaded polylactic acid constructed by electrospinning

    Thu Trang Mai, Thi; Thu Thuy Nguyen, Thi; Duong Le, Quang; Ngoan Nguyen, Thi; Cham Ba, Thi; Binh Nguyen, Hai; Bich Hoa Phan, Thi; Tran, Dai Lam; Phuc Nguyen, Xuan; Park, Jun Seo

    2012-06-01

    Curcumin (Cur), extracted from the Curcuma longa L. plant, is well known for its anti-tumor, anti-oxidant, anti-inflammatory and anti-bacterial properties. Nanofiber mats of polylactic acid (PLA) loading Cur (5 wt%) were fabricated by electrospinning (e-spinning). Morphology and structure of the fibers were characterized by field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively. The diameters of the obtained fibers varied from 200 to 300 nm. The release capacity of curcumin from curcumin-loaded PLA fibers was investigated in phosphate buffer saline (PBS) containing ethanol. After 24 h, 50% of the curcumin was released from curcumin-loaded PLA fibers. These results of electrospun (e-spun) fibers exhibit the potential for biomedical application.

  18. A novel nanofiber Cur-loaded polylactic acid constructed by electrospinning

    Curcumin (Cur), extracted from the Curcuma longa L. plant, is well known for its anti-tumor, anti-oxidant, anti-inflammatory and anti-bacterial properties. Nanofiber mats of polylactic acid (PLA) loading Cur (5 wt%) were fabricated by electrospinning (e-spinning). Morphology and structure of the fibers were characterized by field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively. The diameters of the obtained fibers varied from 200 to 300 nm. The release capacity of curcumin from curcumin-loaded PLA fibers was investigated in phosphate buffer saline (PBS) containing ethanol. After 24 h, 50% of the curcumin was released from curcumin-loaded PLA fibers. These results of electrospun (e-spun) fibers exhibit the potential for biomedical application

  19. Two types of rare earth–organic frameworks constructed by racemic tartaric acid

    Hydrothermal reactions of rare earth oxides with racemic tartaric acid (H2tar) yielded 7 rare earth(III) MOFs with general formulas [R2(tar)3(H2O)2]n (R=Y (1), Sm (4), Eu (5), Tb (6), Dy (7)) and [R2(tar)2(C2O4)(H2O)2]n·4nH2O (R=La (2), Nd (3)). X-ray powder diffraction analysis and single-crystal X-ray diffraction analysis reveal that they present two different structural types. MOFs 1, 4, 5, 6 and 7 are isostructural and crystallize in the orthorhombic non-centrosymmetric space group Iba2, and feature unusual fsc-3,4-Iba2 topology. MOFs 2 and 3 are isostructural and crystallize in monoclinic P21/c space group and display rare fsx-4,5-P21/c topology containing hydrophilic channels bounded by triple helical chains along a axis. MOFs 3, 4, 5, 6 and 7 exhibit intense lanthanide characteristic photoluminescence at room temperature. - Graphical Abstract: [R2(tar)2(C2O4)(H2O)2]n·4nH2O (R=La (2), Nd (3)) display rare fsx-4,5-P21/c topology containing hydrophilic channels bounded by triple helical chains along a axis. Highlights: ► Two types of rare earth MOFs were synthesized by hydrothermal conditions. ► MOFs feature unusual fsc-3,4-Iba2 and rare fsx-4,5-P21/c topology structures. ► MOFs exhibit intense lanthanide characteristic photoluminescence.

  20. Microbial populations identified by fluorescence in situ hybridization in a constructed wetland treating acid coal mine drainage.

    Nicomrat, Duongruitai; Dick, Warren A; Tuovinen, Olli H

    2006-01-01

    Microorganisms are an integral part of the biogeochemical processes in wetlands, yet microbial communities in sediments within constructed wetlands receiving acid mine drainage (AMD) are only poorly understood. The purpose of this study was to characterize the microbial diversity and abundance in a wetland receiving AMD using fluorescence in situ hybridization (FISH) analysis. Seasonal samples of oxic surface sediments, comprised of Fe(III) precipitates, were collected from two treatment cells of the constructed wetland system. The pH of the bulk samples ranged between pH 2.1 and 3.9. Viable counts of acidophilic Fe and S oxidizers and heterotrophs were determined with a most probable number (MPN) method. The MPN counts were only a fraction of the corresponding FISH counts. The sediment samples contained microorganisms in the Bacteria (including the subgroups of acidophilic Fe- and S-oxidizing bacteria and Acidiphilium spp.) and Eukarya domains. Archaea were present in the sediment surface samples at detection in the bacterial community. The results from the FISH technique from this field study are consistent with results from other experiments involving enumeration by most probable number, dot-blot hybridization, and denaturing gradient gel electrophoresis analyses and with the geochemistry of the site. PMID:16825452

  1. Novel lanthanide complexes constructed from 3, 4-dimethoxybenzoic acid: crystal structures, spectrum and thermochemical properties

    Qi, Xiao-Xia; Wu, Jun-Chen [Testing and Analysis Center, Hebei Normal University, Shijiazhuang 050024 (China); College of Chemistry & Material Science, Hebei Normal University, Shijiazhuang 050024 (China); Ren, Ning, E-mail: ningren9@163.com [College of Chemical engineering & Material, Handan College, Handan 056005 (China); Zhao, Chun-Li [Raoyang High School of Hebei, Raoyang 053900 (China); Zhang, Jian-Jun, E-mail: jjzhang6@126.com [Testing and Analysis Center, Hebei Normal University, Shijiazhuang 050024 (China); College of Chemistry & Material Science, Hebei Normal University, Shijiazhuang 050024 (China); Zong, Guang-Cai; Gao, Jie [Testing and Analysis Center, Hebei Normal University, Shijiazhuang 050024 (China); College of Chemistry & Material Science, Hebei Normal University, Shijiazhuang 050024 (China)

    2015-09-10

    Graphical abstract: Four novel lanthanide coordination polymers [Ln(3,4-DMOBA){sub 3}(H{sub 2}O){sub 2}]·H{sub 2}O·C{sub 2}H{sub 5}OH (Ln = Sm(1), Tb(2), Dy(3), Ho(4); 3,4-DMOBA = 3, 4-dimethoxybenzoate) have been hydrothermal synthesized and characterized. Single crystal structures indicates 1 D stucture of the title complexes are linked by hydrogen bonds to form a three-dimensional (3-D) structure. Complex 2 exhibits the characteristic emission of Tb{sup 3+} ion({sup 5}D{sub 4} → {sup 7}F{sub 6-3}). The investigation of TG-FTIR and IR spectra of the evolved gases shows uncoordinated water and ethanol molecules tend to lose firstly, and then 3,4-DMOBA ligands begin to decompose. - Highlights: • Four lanthanide coordination polymers were synthesized and characterized. • 1-D chain structures of the title complexes are are linked by hydrogen bonds to form a 3-D structures. • Thermal decomposition processes of the title complexes were studied using TG-FTIR techniques. • IR spectra of evolved gases in thermal decomposition process were obtained and analyzed. - Abstract: Four novel lanthanide complexes [Ln(3,4-DMOBA){sub 3}(H{sub 2}O){sub 2}]·H{sub 2}O·C{sub 2}H{sub 5}OH (Ln = Sm(1), Tb(2), Dy(3), Ho(4); 3,4-DMOBA = 3, 4-dimethoxybenzoate) have been hydrothermal synthesized and characterized. Structural analyses reveal that adjacent lanthanide ions are connected by 3,4-DMOBA ligands adopting bridging bidentate mode to generate one-dimensional (1-D) structure with the uncoordinated water and ethanol molecules. 1-D structures are linked by hydrogen bonds to form a three-dimensional (3-D) structure, which is rarely observed in lanthanide carboxylic acids complexes. Under the radiation of UV light, complex 2 exhibits the characteristic emission of Tb{sup 3+} ion ({sup 5}D{sub 4} → {sup 7}F{sub 6-3}). The thermal decomposition mechanism is investigated by TG-FTIR technology. IR spectra of the evolved gases show that the uncoordinated water and ethanol

  2. Novel lanthanide complexes constructed from 3, 4-dimethoxybenzoic acid: crystal structures, spectrum and thermochemical properties

    Graphical abstract: Four novel lanthanide coordination polymers [Ln(3,4-DMOBA)3(H2O)2]·H2O·C2H5OH (Ln = Sm(1), Tb(2), Dy(3), Ho(4); 3,4-DMOBA = 3, 4-dimethoxybenzoate) have been hydrothermal synthesized and characterized. Single crystal structures indicates 1 D stucture of the title complexes are linked by hydrogen bonds to form a three-dimensional (3-D) structure. Complex 2 exhibits the characteristic emission of Tb3+ ion(5D4 → 7F6-3). The investigation of TG-FTIR and IR spectra of the evolved gases shows uncoordinated water and ethanol molecules tend to lose firstly, and then 3,4-DMOBA ligands begin to decompose. - Highlights: • Four lanthanide coordination polymers were synthesized and characterized. • 1-D chain structures of the title complexes are are linked by hydrogen bonds to form a 3-D structures. • Thermal decomposition processes of the title complexes were studied using TG-FTIR techniques. • IR spectra of evolved gases in thermal decomposition process were obtained and analyzed. - Abstract: Four novel lanthanide complexes [Ln(3,4-DMOBA)3(H2O)2]·H2O·C2H5OH (Ln = Sm(1), Tb(2), Dy(3), Ho(4); 3,4-DMOBA = 3, 4-dimethoxybenzoate) have been hydrothermal synthesized and characterized. Structural analyses reveal that adjacent lanthanide ions are connected by 3,4-DMOBA ligands adopting bridging bidentate mode to generate one-dimensional (1-D) structure with the uncoordinated water and ethanol molecules. 1-D structures are linked by hydrogen bonds to form a three-dimensional (3-D) structure, which is rarely observed in lanthanide carboxylic acids complexes. Under the radiation of UV light, complex 2 exhibits the characteristic emission of Tb3+ ion (5D4 → 7F6-3). The thermal decomposition mechanism is investigated by TG-FTIR technology. IR spectra of the evolved gases show that the uncoordinated water and ethanol molecules lose in the first step. And then 3,4-DMOBA ligand is decomposed into H2O, CO2 and other gaseous molecules as well as the gaseous

  3. Construction Strategy for an Internal Amplification Control for Real-Time Diagnostic Assays Using Nucleic Acid Sequence-Based Amplification: Development and Clinical Application

    Rodríguez-Lázaro, David; D'Agostino, Martin; Pla, Maria; Cook, Nigel

    2005-01-01

    An important analytical control in molecular amplification-based methods is an internal amplification control (IAC), which should be included in each reaction mixture. An IAC is a nontarget nucleic acid sequence which is coamplified simultaneously with the target sequence. With negative results for the target nucleic acid, the absence of an IAC signal indicates that amplification has failed. A general strategy for the construction of an IAC for inclusion in molecular beacon-based real-time nu...

  4. Construction of Yeast Vectors with Resistance to Geneticin

    林会兰; 张广; 周全; 陈国强

    2002-01-01

    Two Escherichia coli-Saccharomyces cerevisiae shuttle vectors containing a resistance marker to geneticin (G418) are constructed. Both vectors contain a kanamycin-resistant marker (KanMX4) module coding aminoglycoside 3'-phosphotransferase (APH) that renders E. coli resistant to kanamycin and S. cerevisiae to geneticin. These vectors overcome the shortage of the conventional yeast vectors bearing HIS3, TRP1, LEU2, and URA3 modules as selection markers, which require hosts to be auxotrophic. Green fluorescent protein (GFP) is used as the reporter to examine the functions of the vectors. The vectors are powerful tools for the convenient cloning and controlled expression of genes in most S. cerevisiae strains.

  5. Biomonitoring study of a constructed wetland site treating acid mine drainage. Research report, July 1990-June 1992

    Acid Mine Drainage (AMD) from an underground coal mine in the Jones Branch watershed in McCreary County, KY, substantially reduced water quality in Jones Branch. Downstream from the mine seeps, the pH was routinely below 4.5 and concentrations of most heavy metals, especially iron, were elevated. A cattail wetland (1,022 m2) was constructed on Jones Branch in 1989 to obviate the effects of the AMD. Monthly chemical monitoring was performed on the water from above, from below, and from the 26 cells within the wetland. Based on chemical monitoring, the wetland initially improved water quality, increasing the pH and removing substantial amounts of heavy metals. Beginning in the spring of 1991, water quality at the wetland outfall began to decline, and has not improved to date. To augment the chemical monitoring, a biomonitoring study was initiated in the spring of 1990. Acute 48-hr. static tests were conducted with newly hatched fathead minnows (Pimephales promelas). Median lethal concentration (LC50) values determined monthly reflects the decline in water quality at the outfall over time

  6. (1)H NMR metabolomic study of auxotrophic starvation in yeast using Multivariate Curve Resolution-Alternating Least Squares for Pathway Analysis.

    Puig-Castellví, Francesc; Alfonso, Ignacio; Piña, Benjamin; Tauler, Romà

    2016-01-01

    Disruption of specific metabolic pathways constitutes the mode of action of many known toxicants and it is responsible for the adverse phenotypes associated to human genetic defects. Conversely, many industrial applications rely on metabolic alterations of diverse microorganisms, whereas many therapeutic drugs aim to selectively disrupt pathogens' metabolism. In this work we analyzed metabolic changes induced by auxotrophic starvation conditions in yeast in a non-targeted approach, using one-dimensional proton Nuclear Magnetic Resonance spectroscopy ((1)H NMR) and chemometric analyses. Analysis of the raw spectral datasets showed specific changes linked to the different stages during unrestricted yeast growth, as well as specific changes linked to each of the four tested starvation conditions (L-methionine, L-histidine, L-leucine and uracil). Analysis of changes in concentrations of more than 40 metabolites by Multivariate Curve Resolution - Alternating Least Squares (MCR-ALS) showed the normal progression of key metabolites during lag, exponential and stationary unrestricted growth phases, while reflecting the metabolic blockage induced by the starvation conditions. In this case, different metabolic intermediates accumulated over time, allowing identification of the different metabolic pathways specifically affected by each gene disruption. This synergy between NMR metabolomics and molecular biology may have clear implications for both genetic diagnostics and drug development. PMID:27485935

  7. 1H NMR metabolomic study of auxotrophic starvation in yeast using Multivariate Curve Resolution-Alternating Least Squares for Pathway Analysis

    Puig-Castellví, Francesc; Alfonso, Ignacio; Piña, Benjamin; Tauler, Romà

    2016-01-01

    Disruption of specific metabolic pathways constitutes the mode of action of many known toxicants and it is responsible for the adverse phenotypes associated to human genetic defects. Conversely, many industrial applications rely on metabolic alterations of diverse microorganisms, whereas many therapeutic drugs aim to selectively disrupt pathogens’ metabolism. In this work we analyzed metabolic changes induced by auxotrophic starvation conditions in yeast in a non-targeted approach, using one-dimensional proton Nuclear Magnetic Resonance spectroscopy (1H NMR) and chemometric analyses. Analysis of the raw spectral datasets showed specific changes linked to the different stages during unrestricted yeast growth, as well as specific changes linked to each of the four tested starvation conditions (L-methionine, L-histidine, L-leucine and uracil). Analysis of changes in concentrations of more than 40 metabolites by Multivariate Curve Resolution – Alternating Least Squares (MCR-ALS) showed the normal progression of key metabolites during lag, exponential and stationary unrestricted growth phases, while reflecting the metabolic blockage induced by the starvation conditions. In this case, different metabolic intermediates accumulated over time, allowing identification of the different metabolic pathways specifically affected by each gene disruption. This synergy between NMR metabolomics and molecular biology may have clear implications for both genetic diagnostics and drug development. PMID:27485935

  8. Construction and Verification of LuxS-negative Mutants of Streptococcus Mutans and the Effect of the Absence of LuxS Gene on the Acid Tolerance

    YU Dan-ni; CHEN Jie; ZHANG Yao-chao; HAN Yu-zhi

    2009-01-01

    Objective: To knock out the entire Luxs gene of Streptococcus mutans(S.mutans) UA159 strain via homologous recombination and construct a Luxs-deleted mutant strain of S. Mutans. To study the difference between the acid resistance of S. Mutans Ingbritt C international standard strain and the acid resistance of LuxS mutant strain. Methods: Two DNA fragments locating in the upper and downstream of Luxs gene were amplified and a erythromycin resistance gene of PJT10 between them were engineered into PUC19 plasmid for constructing the recombination plasmid pUCluxKO. Electrotransformation of S.mutans cells with pUCluxKO-mutant resulted in isolation of erythromycin resistant S. Mutans transformants, which was identified by polymerase chain reaction, V.harveyi BB170 luminescence bioassay and sequencing analysis. Solutions of S. Mutans standard strain and LuxS mutant strain with same density were made and cultured at pH 3.5 to 7.0 BHI liquid for the same period.Terminal growth situation was compared.Firstly acidized in pH 5.5 BHI liquid,the two strains were cultured at pH 3.0 BHI liquid. The acid tolerance responses of the two strains were compared.Results:Restriction endonuclease analyses showed that pUCluxKO-mutant vector had been successfully recombined. The Luxs-deleted status of S.mutans mutants was confirmed by PCR with primers which were specific for the genes of Luxs and Erythromycin resistance. S.mutans mutant can not induce bioluminescence, indiating the mutant had been successfully recombined. After twenty generations of culture, the constructed Chinese S.mutans mutants were confirmed to be stable. Significant difference of aciduricity was observed between S.mutans standard strain and LuxS mutant strain.The acid resistance of standard strain was stronger than that of LuxS mutant strain.The two strains both displayed the capability of acid tolerance responses. Conclusion:The S.mutans gene allelic exchange plasmid is constructed correctively and a Luxs

  9. Eight supramolecular assemblies constructed from bis(benzimidazole) and organic acids through strong classical hydrogen bonding and weak noncovalent interactions

    Jin, Shouwen; Wang, Daqi

    2014-05-01

    Eight crystalline organic acid-base adducts derived from alkane bridged bis(N-benzimidazole) and organic acids (2,4,6-trinitrophenol, p-nitrobenzoic acid, m-nitrobenzoic acid, 3,5-dinitrobenzoic acid, 5-sulfosalicylic acid and oxalic acid) were prepared and characterized by X-ray diffraction analysis, IR, mp, and elemental analysis. Of the eight compounds five are organic salts (1, 4, 6, 7 and 8) and the other three (2, 3, and 5) are cocrystals. In all of the adducts except 1 and 8, the ratio of the acid and the base is 2:1. All eight supramolecular assemblies involve extensive intermolecular classical hydrogen bonds as well as other noncovalent interactions. The role of weak and strong noncovalent interactions in the crystal packing is ascertained. These weak interactions combined, all the complexes displayed 3D framework structure. The results presented herein indicate that the strength and directionality of the classical N+-H⋯O-, O-H⋯O, and O-H⋯N hydrogen bonds (ionic or neutral) and other nonbonding associations between acids and ditopic benzimidazoles are sufficient to bring about the formation of cocrystals or organic salts.

  10. Multicomponent hydrogen-bonding organic solids constructed from 6-hydroxy-2-naphthoic acid and N-heterocycles: Synthesis, structural characterization and synthon discussion

    Zong, Yingxia; Shao, Hui; Pang, Yanyan; Wang, Debao; Liu, Kang; Wang, Lei

    2016-07-01

    Seven novel multicomponent crystals involving various substituted organic amine molecules and 6-hydroxy-2-naphthoic acid were prepared and characterized by using single crystal X-ray diffraction, infrared and thermogravimetric analyses (TGA). Crystal structures with 1,4-bis(imidazol) butane (L1) 1, 1,4-bis(imidazol-1-ylmethyl)benzene (L2) 2, 1-phenyl piperazine 3, 2-amino-4-hydroxy-6-methyl pyrimidine 4, 4,4'-bipyridine 5, 5,5'-dimethyl-2,2'-dipyridine 6, 2-amino-4,6-dimethyl pyrimidine 7 were determined. Among the seven molecular complexes, total proton transfer from 6-hydroxy-2-naphthoic acid to coformer has occurred in crystals 1-4, while the remaining were cocrystals. X-ray single-crystal structures of these complexes reveal that strong hydrogen bonding O-H···O/N-H···O/O-H···N and weak C-H···O/C-H···π/π···π intermolecular interactions direct the packing modes of molecular crystals together. The analysis of supramolecular synthons in the present structures shows that some classical supramolecular synthons like pyridine-carboxylic acid heterosynthon R22 (7) and aminopyridine-carboxylic acid heterosynthon R22 (8), are again observed in constructing the hydrogen-bonding networks in this paper. Besides, we noticed that water molecules act as a significant hydrogen-bonding connector in constructing supramolecular architectures of 3, 4, 6, and 7.

  11. Processing large-diameter poly(L-lactic acid) microfiber mesh/mesenchymal stromal cell constructs via resin embedding: an efficient histologic method

    In this study, we performed a complete histologic analysis of constructs based on large diameter ( > 100 μm) poly-L-lactic acid (PLLA) microfibers obtained via dry-wet spinning and rat Mesenchymal Stromal Cells (rMSCs) differentiated towards the osteogenic lineage, using acrylic resin embedding. In many synthetic polymer-based microfiber meshes, ex post processability of fiber/cell constructs for histologic analysis may face deterring difficulties, leading to an incomplete investigation of the potential of these scaffolds. Indeed, while polymeric nanofiber (fiber diameter = tens of nanometers)/cell constructs can usually be embedded in common histologic media and easily sectioned, preserving the material structure and the antigenic reactivity, histologic analysis of large polymeric microfiber/cell constructs in the literature is really scant. This affects microfiber scaffolds based on FDA-approved and widely used polymers such as PLLA and its copolymers. Indeed, for such constructs, especially those with fiber diameter and fiber interspace much larger than cell size, standard histologic processing is usually inefficient due to inhomogeneous hardness and lack of cohesion between the synthetic and the biological phases under sectioning. In this study, the microfiber/MSC constructs were embedded in acrylic resin and the staining/reaction procedures were calibrated to demonstrate the possibility of successfully employing histologic methods in tissue engineering studies even in such difficult cases. We histologically investigated the main osteogenic markers and extracellular matrix molecules, such as alkaline phosphatase, osteopontin, osteocalcin, TGF-β1, Runx2, Collagen type I and the presence of amorphous, fibrillar and mineralized matrix. Biochemical tests were employed to confirm our findings. This protocol permitted efficient sectioning of the treated constructs and good penetration of the histologic reagents, thus allowing distribution and expression of

  12. Oxygen-dependent catabolism of indole-3-acetic acid in Bradyrhizobium japonicum

    Egebo, L A; Nielsen, S V; Jochimsen, B U

    1991-01-01

    Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid (IAA). Examination of this catabolism in strain 110 by in vivo experiments has revealed an enzymatic activity catalyzing the degradation of IAA and 5-hydroxy-indole-3-acetic acid. The activity requires...... oxygen-consuming opening of the indole ring analogous to the one catalyzed by tryptophan 2,3-dioxygenase. The pattern of metabolite usage by known tryptophan-auxotrophic mutants and studies of metabolites by high-performance liquid chromatography indicate that anthranilic acid is a terminal degradation...

  13. Construction of a Recombinant Leuconostoc mesenteroides CJNU 0147 Producing 1,4-Dihydroxy-2-Naphthoic Acid, a Bifidogenic Growth Factor.

    Eom, Ji-Eun; Moon, Gi-Seong

    2015-01-01

    1,4-Dihydroxy-2-naphthoic acid (DHNA), a precursor of menaquinone (vitamin K2), has an effect on growth stimulation of bifidobacteria and prevention of osteoporosis, making it a promising functional food material. Therefore, we tried to clone the menB gene encoding DHNA synthase from Leuconostoc mesenteroides CJNU 0147. Based on the genome sequence of Leu. mesenteroides ATCC 8293 (GenBank accession no., CP000414), a primer set (Leu_menBfull_F and Leu_menBfull_R) was designed for the PCR amplification of menB gene of CJNU 0147. A DNA fragment (1,190 bp), including the menB gene, was amplified, cloned into pGEM-T Easy vector, and sequenced. The deduced amino acid sequence of MenB (DHNA synthase) protein of CJNU 0147 had a 98% similarity to the corresponding protein of ATCC 8293. The menB gene was subcloned into pCW4, a lactic acid bacteria - E. coli shuttle vector, and transferred to CJNU 0147. The transcription of menB gene of CJNU 0147 (pCW4::menB) was increased, when compared with those of CJNU 0147 (pCW4) and CJNU 0147 (-). The DHNA was produced from it at a detectable level, indicating that the cloned menB gene of CJNU 0147 encoded a DHNA synthase which is responsible for the production of DHNA, resulting in an increase of bifidogenic growth stimulation activity. PMID:26877648

  14. Identification of novel secreted fatty acids that regulate nitrogen catabolite repression in fission yeast

    Sun, Xiaoying; Hirai, Go; Ueki, Masashi; Hirota, Hiroshi; Wang, Qianqian; Hongo, Yayoi; Nakamura, Takemichi; Hitora, Yuki; Takahashi, Hidekazu; Sodeoka, Mikiko; Osada, Hiroyuki; Hamamoto, Makiko; Yoshida, Minoru; Yashiroda, Yoko

    2016-01-01

    Uptake of poor nitrogen sources such as branched-chain amino acids is repressed in the presence of high-quality nitrogen sources such as NH4+ and glutamate (Glu), which is called nitrogen catabolite repression. Amino acid auxotrophic mutants of the fission yeast Schizosaccharomyces pombe were unable to grow on minimal medium containing NH4Cl or Glu even when adequate amounts of required amino acids were supplied. However, growth of these mutant cells was recovered in the vicinity of colonies of the prototrophic strain, suggesting that the prototrophic cells secrete some substances that can restore uptake of amino acids by an unknown mechanism. We identified the novel fatty acids, 10(R)-acetoxy-8(Z)-octadecenoic acid and 10(R)-hydroxy-8(Z)-octadecenoic acid, as secreted active substances, referred to as Nitrogen Signaling Factors (NSFs). Synthetic NSFs were also able to shift nitrogen source utilization from high-quality to poor nitrogen sources to allow adaptive growth of the fission yeast amino acid auxotrophic mutants in the presence of high-quality nitrogen sources. Finally, we demonstrated that the Agp3 amino acid transporter was involved in the adaptive growth. The data highlight a novel intra-species communication system for adaptation to environmental nutritional conditions in fission yeast. PMID:26892493

  15. New silver(I) coordination polymers constructed from pyrazine derivatives and aromatic carboxylic acids: Syntheses, structures and photoluminescence

    Zhang, Ting; Huang, Hua-Qi; Mei, Hong-Xin; Wang, Dan-Feng; Wang, Xiao-Xiang; Huang, Rong-Bin; Zheng, Lan-Sun

    2015-11-01

    Five one-dimensional to three-dimensional coordination polymers have been synthesized by 2-chlorobenzoic acid (HL1), 2-nitrobenzoic acid (HL2), o-toluic acid (HL3), 2,3,5-trimethylpyrazine (tpyz) and 2,3,5,6-tetramethylpyrazine (mpyz) in the presence of NH3·H2O in mixed solvents systems, namely, {Ag4(tpyz)2(L1)4}n (1), {Ag2(tpyz) (L2)2}n (2), {Ag2(tpyz) (L3)2}n (3), {Ag2(mpyz) (L1)2}n (4), {Ag(mpyz) (L2) (H2O)}n (5). All the complexes have been characterized by elemental analyses, IR spectra and X-ray diffraction. Compound 1 shows a 3D framework. The tpyz ligand links 1D chain which was connected by silver atom and L1 anion into 3D framework. Compounds 2 and 4 possess a similar 2D network with (4, 4) topology. Complex 3 also exhibits a two-dimensional structure. There is a 1D silver chain in 3, which is the main difference from 2 and 4. So, 3 shows three-connected (4 8, 3) topology. For 5, only one oxygen of L2 coordinated to Ag(I) ions. The L2 anions were arranged in both sides of the chain, which was connected by silver atoms and mpyz ligands. Then, the uncoordinated carboxylate oxygen with coordinated water 1molecule oxygen through the hydrogen bond made the resultant structure to a 3D framework. Complexes 1-5 spanning from one-dimensional chains to three-dimensional framework suggest that carboxylates and the kinds of pyrazine derivatives play significant roles in the formation of such coordination architectures. The photoluminescence and thermogravimetric analysis (TGA) of the complexes were also investigated.

  16. Comparative genomics of the lactic acid bacteria

    Makarova, K.; Slesarev, A.; Wolf, Y.; Sorokin, A.; Mirkin, B.; Koonin, E.; Pavlov, A.; Pavlova, N.; Karamychev, V.; Polouchine, N.; Shakhova, V.; Grigoriev, I.; Lou, Y.; Rokhsar, D.; Lucas, S.; Huang, K.; Goodstein, D. M.; Hawkins, T.; Plengvidhya, V.; Welker, D.; Hughes, J.; Goh, Y.; Benson, A.; Baldwin, K.; Lee, J. -H.; Diaz-Muniz, I.; Dosti, B.; Smeianov, V; Wechter, W.; Barabote, R.; Lorca, G.; Altermann, E.; Barrangou, R.; Ganesan, B.; Xie, Y.; Rawsthorne, H.; Tamir, D.; Parker, C.; Breidt, F.; Broadbent, J.; Hutkins, R.; O' Sullivan, D.; Steele, J.; Unlu, G.; Saier, M.; Klaenhammer, T.; Richardson, P.; Kozyavkin, S.; Weimer, B.; Mills, D.

    2006-06-01

    Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains. Phylogenetic analyses, comparison of gene content across the group, and reconstruction of ancestral gene sets indicate a combination of extensive gene loss and key gene acquisitions via horizontal gene transfer during the coevolution of lactic acid bacteria with their habitats.

  17. 产L 苹果酸重组大肠杆菌的构建%Construction of recombinant Escherichia coli for L-malic acid production

    吴亚斌; 张梁; 石贵阳

    2014-01-01

    Based on the synthesis pathway of succinic acid in E�coli B0013-1050,the synthesize pathway of L-malic acid was constructed by using Red homologus recombination combined with Xer/dif recombinase system to delete the gene fumB,fumC and maeB from chromosome,and a recombinant strain E�coli 2030 was obtained�L-malic acid of 12�5 g/L with yield of 52�1% was achieved in a 15-L bioreactor. The main by-products, including pyruvic acid and succinic acid were analyzed�To increase the yield of L-malic acid, the malate dehydrogenase encoded gene mdh from Aspergillus flavus was integrantly expressed as the recombinant strain and a recombinant strain E�coli 2040 was obtained. The concentration and the yield of L-malic acid increased to 14 g/L and 60�3% in a 15-L bioreactor, respectively�%基于产琥珀酸重组大肠杆菌E�coli B00131050的琥珀酸合成途径,利用Red同源重组技术结合Xer/dif重组系统敲除富马酸酶基因fumB、fumC,苹果酸酶基因maeB,构建L 苹果酸合成途径,最终得到重组大肠杆菌E�coli 2030,该菌株在15 L发酵罐中,产L 苹果酸12�5 g/L,葡萄糖苹果酸转化率为52�1%,同时对发酵产物中主要杂酸丙酮酸和琥珀酸的生产原因进行了初步的探讨与分析。为进一步提高L 苹果酸的转化率,整合表达来源于黄曲霉的苹果酸脱氢酶基因,构建重组菌E�coli 2040,在15 L发酵罐中产L 苹果酸14 g/L,葡萄糖苹果酸转化率提高到60�3%。

  18. Validity of manganese as a surrogate of heavy metals removal in constructed wetlands treating acidic mine water

    The evaluation of manganese as a surrogate for heavy metal behavior in two wetland treatment systems receiving acidic coal mine drainage in central Pennsylvania was investigated. The use of manganese as an indicator is based on physical/chemical treatment processes quite different from wetland treatment. The treatment systems represented one anoxic, subsurface flow system and one oxic surface flow system. Water quality parameters measured included pH, alkalinity, acidity, and a suite of metals. Correlation and linear regression analysis were used to evaluate the ability of a candidate predictor variable (indicator) to predict heavy metal concentrations and removal. The use of manganese as a predictor of effluent quality proved to be poor in both wetland treatment systems, as evidenced by low linear R2 values and negative correlations. Zinc emerged as the best predictor of the detectable heavy metals at the anoxic wetland. Zinc exhibited positive strong linear correlations with copper, cobalt, and nickel (R2 values of 0.843, 0.881, and 0.970, respectively). Effluent pH was a slightly better predictor of effluent copper levels in the anoxic wetland. Iron and cobalt effluent concentrations showed the only strong relationship (R2 value = 0.778) in the oxic system. The lack of good correlations with manganese strongly challenges its appropriateness as a surrogate for heavy metals in these systems

  19. Construction of antibacterial poly(ethylene terephthalate) films via layer by layer assembly of chitosan and hyaluronic acid.

    Del Hoyo-Gallego, Sara; Pérez-Álvarez, Leyre; Gómez-Galván, Flor; Lizundia, Erlantz; Kuritka, Ivo; Sedlarik, Vladimir; Laza, Jose Manuel; Vila-Vilela, Jose Luis

    2016-06-01

    Polyelectrolytic multilayers (PEMs) with enhanced antibacterial properties were built up onto commercial poly(ethylene terephthalate) (PET) films based on the layer by layer assembling of bacterial contact killing chitosan and bacterial repelling highly hydrated hyaluronic acid. The optimization of the aminolysis modification reaction of PET was carried out by the study of the mechanical properties and the surface characterization of the modified polymers. The layer by layer assembly was successfully monitored by TEM microscopy, surface zeta-potential, contact angle measurements and, after labeling with fluorescein isothiocyanate (FTIC) by absorption spectroscopy and confocal fluorescent microscopy. Beside, the stability of the PEMs was studied at physiological conditions in absence and in the presence of lysozyme and hyaluronidase enzymes. Antibacterial properties of the obtained PEMs against Escherichia coli were compared with original commercial PET. PMID:27083341

  20. Usefulness of biodegradable stents constructed of poly-/-lactic acid monofilaments in patients with benign esophageal stenosis

    2007-01-01

    AIM: To report 13 patients with benign esophageal stenosis treated with the biodegradable stent.METHODS: We developed a Ultraflex-type stent by knitting poly-l-lactic acid monofilaments.RESULTS: Two cases were esophageal stenosis caused by drinking of caustic liquid, 4 cases were due to surgical resection of esophageal cancers, and 7 cases were patients with esophageal cancer who received the preventive placement of biodegradable stents for postendoscopic mucosal dissection (ESD) stenosis. The preventive placement was performed within 2 to 3 d after ESD. In 10 of the 13 cases, spontaneous migration of the stents occurred between 10 to 21 d after placement. In these cases, the migrated stents were excreted with the feces, and no obstructive complications were experienced. In 3 cases, the stents remained at the proper location on d 21 after placement. No symptoms of re-stenosis were observed within the follow-up period of 7 mo to 2 years. Further treatment with balloon dilatation or replacement of the biodegradable stent was not required.CONCLUSION: Biodegradable stents were useful for the treatment of benign esophageal stenosis, particularly for the prevention of post-ESD stenosis.

  1. Synthesis and Characterization of Two New Chiral Copper(Ⅱ) Compounds Constructed from (+)-N-TosyI-L-glutamic Acid

    He Rong; Song Huihua; Wu Lili; Wei Zhen; Wang Tao

    2011-01-01

    Chiral coordination polymers have attracted intense interest mainly due to their potential applications. Hence, two new chiral copper(Ⅱ) coordination polymers { [Cu(tsgluO)(H2O)]2·3H2O}n (1) and [Cu(tsgluO)(2,2'-bipy)]n (2)(H2tsglu=(+)-N-tosyl-l-glutamic acid; 2,2'-bipy=2,2'-bipyridine) were synthesized in the absence or presence of 2,2'-bipy ligand and structurally characterized. A single crystal X-ray diffraction study revealed that compound 1 consists of a paddle-wheel dicopper(Ⅱ) core, which links other equivalents via four tsgluO2- ligands to form a 1D double chain. Such a chain is further interconnected through weak π-π stacking and hydrogen bonding interactions to form a 3D H-bonded supramolecular structure with 1D channels hosting lattice water molecules. Whereas, com-pound 2, containing the coordinating 2,2'-bipy, gives rise to a ladder-like 1D double chain. Antiferromagnetic in-teractions were observed in 1 and 2.

  2. Synthesis, Structures and Photoluminescent Properties of Two Novel Zinc(II) Compounds Constructed from 5-Sulfoisophthalic Acid

    Hydrothermal reaction of zinc(II) salts with 5-sulfoisophthalic acid monosodium salt (NaO3SC6H3-1,3-(COOH)2, NaH2- SIP) and 1,10-phenanthroline (phen) led to two new compounds, [Zn(phen)3]·2H2SIP·4H2O and [Zn(phen)2(H2O)2]· 2H2SIP·2H2O. They were characterized by element analysis, IR spectroscopy, thermal gravimetric analysis (TGA), X-ray powder diffraction (XRD), and single-crystal X-ray diffraction. Both compounds 1-2 represent the first example of Zn/phen/SIP system. The Zn (II) ion in 1 is six-coordinated by six nitrogen atoms from three phen molecules, and the H2SIP- ligands engage in the formation of hydrogen bond. The Zn(II) ion in 2 is coordinated by four nitrogen atoms from two phen molecules and two oxygen atoms from two water molecules. Moreover, both 1 and 2 are assembled into 3D supramolecular architectures by hydrogen bonds (O-H···O) and π-π interactions. Solvent water molecules occupying voids of the compounds serve as receptors or donors of the extensive O-H···O hydrogen bonds

  3. Structural variations and photoluminescent properties of a series of metal-organic frameworks constructed from 5-(4-carboxybenzoylamino)-isophthalic acid

    Five new metal-organic frameworks (MOFs) with 5-(4-carboxybenzoylamino)-isophthalic acid (H3L), namely, [Cd9L6(DMA)6]·4DMA (1), [Cd3L2(H2O)9]·4H2O (2), [LaL(H2O)4]·2H2O (3), [CeL(H2O)4]·H2O (4) and [Tb(HL)(H2L)(H2O)3]·5H2O (5) (DMA=N,N-dimethylacetamide), have been synthesized. Complex 1 shows a three-dimensional architecture generated from linkage of Cd–O chains via L3− ligands. Minor variations in synthetic conditions of 1 afforded 2, which features an interesting 2D→3D catenation architecture containing helical chains. Complexes 3 and 4 are isostructural and each feature a two-dimensional architecture constructed from the linkage of L3− with Ln3+. Complex 5 displays a chain-like structure, of which the most interesting feature is the existence of free carboxylic acid (–COOH) group which may confer unique functionality. Moreover, the investigations of the thermal stability, powder X-ray diffractions and solid-state photoluminescent properties for these crystalline materials have been carried out. - Graphical Abstract: Solvothermal reactions of tricarboxylate ligand H3L with Cd2+/Ln3+ has yielded a series of new MOFs containing interesting structural motifs. - Highlights: • A tricarboxylate ligand whose coordinating functionalities are not symmetry equivalent is employed to construct MOFs. • Complex 2 features an interesting 2D→3D catenation architecture containing helical chains. • Complex 3 feature chain-like structure containing free – COOH group, which may confer unique functionality. • Photoluminescent properties and thermal behaviors for 1–5 have been reported

  4. Construction of Prokaryotic Expressing Vector of Antisense Nucleic Acid of LasR and Its Effect on the Virulence of Pseudomonas Aeruginosus

    ZHANG Ling; ZHOU Junli; LI Jingming; LIAO Fang

    2007-01-01

    To construct a pUCP18/lasRantisense plasmid carrying the reversed gene and analyze its effect on the virulence of Pseudomonas aeruginosus, LasR gene was amplified from the genome of Pseudomonas aeruginosus by PCR and reversely recombined with plasmid pUCP18. The recombinant pUCP18/lasRantisense was verified by enzyme digestion, PCR and sequencing. The biological effects of pUCP18/lasRantisense were examined by using RT-PCR, NAD method and the assay of pyocyanin. Our results showed that the expected full length lasR fragment (721 bp) was extended from Pseudomonas aeruginosus gene with PCR. And it is consistent with LasR gene of Pseudomonas aeruginosa in GenBank (No. NC_002516). The recombinant plasmid was successfully constructed and transferred into Pseudomonas aeruginosus. The antisense nucleic acid of LasR gene could reduce the virulence of Pseudomonas aeruginosus and might serve as a new target site for treatment purpose.

  5. Neural network consistent empirical physical formula construction for density functional theory based nonlinear vibrational absorbance and intensity of 6-choloronicotinic acid molecule

    Yildiz, Nihat; Karabacak, Mehmet; Kurt, Mustafa; Akkoyun, Serkan

    2012-05-01

    Being directly related to the electric charge distributions in a molecule, the vibrational spectra intensities are both experimentally and theoretically important physical quantities. However, these intensities are inherently highly nonlinear and of complex pattern. Therefore, in particular for unknown detailed spatial molecular structures, it is difficult to make ab initio intensity calculations to compare with new experimental data. In this respect, we very recently initiated entirely novel layered feedforward neural network (LFNN) approach to construct empirical physical formulas (EPFs) for density functional theory (DFT) vibrational spectra of some molecules. In this paper, as a new and far improved contribution to our novel molecular vibrational spectra LFNN-EPF approach, we constructed LFFN-EPFs for absorbances and intensities of 6-choloronicotinic acid (6-CNA) molecule. The 6-CNA data, borrowed from our previous study, was entirely different and much larger than the vibrational intensity data of our formerly used LFNN-EPF molecules. In line with our another previous work which theoretically proved the LFNN relevance to EPFs, although the 6-CNA DFT absorbance and intensity were inherently highly nonlinear and sharply fluctuating in character, still the optimally constructed train set LFFN-EPFs very successfully fitted the absorbances and intensities. Moreover, test set (i.e. yet-to-be measured experimental data) LFNN-EPFs consistently and successfully predicted the absorbance and intensity data. This simply means that the physical law embedded in the 6-CNA vibrational data was successfully extracted by the LFNN-EPFs. In conclusion, these vibrational LFNN-EPFs are of explicit form. Therefore, by various suitable operations of mathematical analysis, they can be used to estimate the electronic charge distributions of the unknown molecule of the significant complexity. Additionally, these estimations can be combined with those of theoretical DFT atomic polar

  6. Physical size of the donor locus and transmission of Haemophilus influenzae ampicillin resistance genes by deoxyribonucleic acid-mediated transformation

    The properties of donor deoxyribonucleic acid (DNA) from three clinical isolates and its ability to mediate the transformation of competent Rd strains to ampicillin resistance were examined. A quantitative technique for determining the resistance of individual Haemophilus influenzae cells to ampicillin was developed. When this technique was used, sensitive cells failed to tolerate levels of ampicillin greater than 0.1 to 0.2 μg/ml, whereas three resistant type b β-lactamase-producing strains could form colonies 1- to 3-μg/ml levels of the antibiotic. DNA extracted from the resistant strains elicited transformation of the auxotrophic genes in a multiply auxotrophic Rd strain. For two of the donors, transformation to ampicillin resistance occurred after the uptake of a single DNA molecule approximately 104-fold less frequently than transformation of auxotrophic loci and was not observed to occur at all with the third. The frequency of transformation to ampicillin resistance was two- to fivefold higher in strain BC200 (Okinaka and Barnhart, 1974), which was cured of a defective prophage. All three clinical ampicillin-resistant strains were poor recipients, but the presence of the ampicillin resistant genes in strain BC200 did not reduce its competence

  7. Dosimetric Applications of Electronic Paramagnetic Resonance Measurements of Free Radicals Formed in Amino Acids: Construction of a Tissue-Equivalent Dosimeter Based on Alanine

    In the case of amino acids rupture of the molecules due to the action of radiation is found to produce free radicals. The number of these radicals can be measured by means of an electronic paramagnetic resonance spectrometer and this number is proportional to the dose absorbed. Alanine has been used for this purpose since it possesses this property over a wide dose range (from 10 to 5 x 106 rads). The present paper covers essentially the following points: (a) Pre-irradiation effect in non-irradiated alanine: this dose limits the minimum measurable dose to approximately 10 rads. The origin of this dose and means of re- ducing it have been studied; (b) Energy response of the alanine: by virtue of the close similarity of its composition to that of tissue, this dosimeter has a good energy response for gamma radiations; the loss of efficiency at low energies can be corrected by the addition of a higher Z material (Ba or Ca); (c) Response to neutrons: with neutrons the radical yield is lower than in the case of gamma radiation, although this yield can be increased by adding a hydrogenated substance (paraffin); (d) Construction of a dosimeter in pellet form: the addition of paraffin improves the response to neutrons and enables moulded pellets of the mixture to be produced. These are easier to use than alanine in powder form and the dosimeters can be produced in any desired form. (author)

  8. Construction of a Multiplex Promoter Reporter Platform to Monitor Staphylococcus aureus Virulence Gene Expression and the Identification of Usnic Acid as a Potent Suppressor of psm Gene Expression.

    Gao, Peng; Wang, Yanli; Villanueva, Iván; Ho, Pak Leung; Davies, Julian; Kao, Richard Yi Tsun

    2016-01-01

    As antibiotic resistance becomes phenomenal, alternative therapeutic strategies for bacterial infections such as anti-virulence treatments have been advocated. We have constructed a total of 20 gfp-luxABCDE dual-reporter plasmids with selected promoters from S. aureus virulence-associated genes. The plasmids were introduced into various S. aureus strains to establish a gfp-lux based multiplex promoter reporter platform for monitoring S. aureus virulence gene expressions in real time to identify factors or compounds that may perturb virulence of S. aureus. The gene expression profiles monitored by luminescence correlated well with qRT-PCR results and extrinsic factors including carbon dioxide and some antibiotics were shown to suppress or induce the expression of virulence factors in this platform. Using this platform, sub-inhibitory ampicillin was shown to be a potent inducer for the expression of many virulence factors in S. aureus. Bacterial adherence and invasion assays using mammalian cells were employed to measure S. aureus virulence induced by ampicillin. The platform was used for screening of natural extracts that perturb the virulence of S. aureus and usnic acid was identified to be a potent repressor for the expression of psm. PMID:27625639

  9. A New Dinuclear Gadolinium Complex Constructed from p-Phenylenediamine-N,N, N,N'-tetraacetic Acid and in situ Generated Oxalate

    YU Fang-Yong; HAO Zhi-Feng; LI Hai-Feng; HUSheng

    2012-01-01

    Routine solution reaction of Gd3+ and p-phenylenediamine-N,N,N′,N′-tetraacetic acid (p-PhDTA) yields a dinuclear complex [Gd2(ox)(p-PhDTA)2(H2O)10]·6H2O (ox = oxalate), which was characterized by single-crystal X-ray diffraction (MoKα radiation, = 0.71073), elemental analysis and IR. This complex crystallizes in the monoclinic system, space group P21/n with a = 10.2522(8), b = 10.0053(8), c = 23.8834(18), = 99.1080(10)°, V = 2419.0(3)3, Z = 2, Mr = 1367.32, Dc = 1.877 g/cm3, F(000) = 1368, = 2.830 mm-1, the final R = 0.0337 and wR = 0.0794 for 4747 observed reflections (I 〉 2 (I)). The exo-tetradentate oxalate ligand, generated in situ from the oxidative coupling of methanol, is incorporated to construct a dinuclear Gd2(ox)2 unit decorated with p-PhDTA ligands on the two sides with a monodentate coordination mode. The dinuclear molecules are further connected by the lattice water molecules to form a three-dimen- sional hydrogen network.

  10. Two new coordination polymers constructed by naphthalene-1,4-dicarboxylic acid and 2,4-diamino-6-methyl-triazine

    Li, Yamin; Xiao, Changyu; Zhang, Xudong; Xu, Yanhui; Li, Junrui; Lun, Huijie; Chen, Qi

    2013-08-01

    Two new transition metal coordination complexes, {[MnO(nda)](H2dmt)(H2O)}n (1), [Ag5(nda)2.5(dmt)]n (2), (H2nda=naphthalene-1,4-dicarboxylic acid, dmt=2,4-diamine-6-methyl-1,3,5-triazine) have been hydrothermally synthesized by the reactions of H2nda and dmt with the homologous MnCl2·4H2O and AgNO3, respectively, and characterized by single-crystal X-ray diffraction, IR spectra, elemental analysis, thermogravimetric analysis (TGA). The compound 1 exhibits a 3D network comprising 1D metal chain {MnO(CO2)2}n connected by the ligand nda2-, featuring a four-connected uninodal diamond -like topology. In compound 2, it is firstly observed that decanuclear silver units as secondary building units to construct 3D network by the ligands dmt and nda2-, with a rare 2-nodal (3,8)-connected tfz-d topology ({43}2{46.618.84}). The interactions within each Mn(II)-Mn(II) pair of compound 1 are antiferromagnetic (g=2.07, J=-1.42(1) cm-1, zj‧=-0.73(2) cm-1). In addition, compound 2 exhibits photoluminescent property at about 472 nm (λex=394 nm).

  11. Synthesis, structures of four coordination compounds constructed from o-methacrylamidobenzoic acid and their relationship between structure and solid state luminescence

    Four new coordination compounds, namely, Zn(o-MAABA)2(Phen) (1), [Cd(o-MAABA)2·2H2O]2 (2), ([Pb2Cl2(o-MAABA)2(Phen)4])·2H2O (3·2H2O), [Pb(NO3)(o-MAABA)(Phen)]n (4), where o-MAABA=o-methacrylamidobenzoic acid and phen=1, 10-phenanthroline, have been synthesized. All compounds were fully confirmed by FT-IR, elemental analysis and TGA analysis. Their structures were determined by single crystal X-ray diffraction, in which compound 1 shows a mononuclear structure, compounds 2 and 3 have binuclear structures and compound 4 shows an infinite chain. In 2 and 4, the adjacent chains are extended into a 3D supramolecular architecture via π–π interactions. Solid-state room temperature luminescence spectra revealed that emission bands of compound 1 were located at 524 nm (λex=352 nm) and compound 4 at 479 and 584 nm (λex=390 nm) assigned to the excimer formation. The emission at 454 nm (λex=340 nm) of compound 2 was mainly ascribed to the Ligand–Metal Charge Transfer (LMCT). - Graphical abstract: Four coordination compounds constructed by o-methacrylamidobenzoic, phenanthroline and metal ions are reported. The photoluminescent properties is studied, which is affected by the molecular stacking and LMCT.

  12. Construction and immunological evaluation of truncated hepatitis B core particles carrying HBsAg amino acids 119-152 in the major immunodominant region (MIR).

    Su, Qiudong; Yi, Yao; Guo, Minzhuo; Qiu, Feng; Jia, Zhiyuan; Lu, Xuexin; Meng, Qingling; Bi, Shengli

    2013-09-13

    Hepatitis B capsid protein expressed in Escherichia coli can reassemble into icosahedral particles, which could strongly enhance the immunogenicity of foreign epitopes, especially those inserted into its major immunodominant region. Herein, we inserted the entire 'α' antigenic determinant amino acids (aa) 119-152 of HBsAg into the truncated HBc (aa 1-144), between Asp(78) and Pro(79). Prokaryotic expression showed that the mosaic HBc was mainly in the form of inclusion bodies. After denaturation with urea, it was dialyzed progressively for protein renaturation. We observed that before and after renaturation, mosaic HBc was antigenic as determined by HBsAg ELISA and a lot of viruslike particles were observed after renaturation. Thus, we further purified the mosaic viruslike particles by (NH4)2SO4 precipitation, DEAE chromatography, and Sepharose 4FF chromatography. Negative staining electron microscopy demonstrated the morphology of the viruslike particles. Immunization of Balb/c mice with mosaic particles induced the production of anti-HBs antibody and Th1 cell immune response supported by ELISPOT and CD4/CD8 proportions assay. In conclusion, we constructed mosaic hepatitis core particles displaying the entire 'α' antigenic determinant on the surface and laid a foundation for researching therapeutic hepatits B vaccines. PMID:23969156

  13. Accelerated healing of diabetic wound using artificial dermis constructed with adipose stem cells and poly(L-glutamic acid)/chitosan scaffold

    SHEN Ting; PAN Zhi-gang; ZHOU Xiao; HONG Chao-yang

    2013-01-01

    Background Diabetic wound is one of the most serious complications of diabetes mellitus.There are no significantly effective therapies for chronic non-healing diabetes ulcer so far.This study aimed to explore the feasibility of healing impaired wound using artificial dermis constructed with human adipose derived stem cells (ASCs) and poly(L-glutamic acid)/chitosan (PLGA/CS) scaffold in streptozotocin-induced diabetic mice.Methods ASCs were isolated from fresh human lipoaspirates and expanded ex vivo for three passages,and then cells were seeded onto PLGA/CS scaffold to form artificial dermis.Expression of VEGF and TGFβ1 by ASCs presented in artificial dermis was determined.The artificial dermis was transplanted to treat the 20 mm × 20 mm full-thickness cutaneous wound created on the back of diabetic mice.Wound treated with scaffold alone and without treatment,and wound in normal non-diabetic mice served as control.Results Cells growing within scaffold showed great proliferation potential,depositing abundant collagen matrix.Meanwhile,expression of VEGF and TGF-β1 by seeded ASCs maintained at a consistent high level.After treated with ASC based artificial dermis,diabetic wounds exhibited significantly higher healing rate compared with wounds treated with scaffold alone or without treatment.Histological examination also demonstrated an improvement in cutaneous restoration with matrix deposition and organization.Further quantitative analysis showed that there was a significant increase in dermis thickness and collagen content on artificial dermis treated wounds.Conclusion ASC/PLGA artificial dermis can effectively accelerate diabetic wound healing by promoting angiogenic growth factors and dermal collagen synthesis.

  14. Construction and immunological evaluation of truncated hepatitis B core particles carrying HBsAg amino acids 119–152 in the major immunodominant region (MIR)

    Highlights: •The conformational HBV neutralization antigen domain was successfully displayed on the surface of truncated HBc particles. •Appropriate dialysis procedures to support the renaturing environment for the protein refolding. •Efficient purification procedures to obtain high purity and icosahedral particles of mosaic HBV antigen. •Strong immune responses not only including neutralization antibody response but also Th1 cell response were induced in mice. -- Abstract: Hepatitis B capsid protein expressed in Escherichia coli can reassemble into icosahedral particles, which could strongly enhance the immunogenicity of foreign epitopes, especially those inserted into its major immunodominant region. Herein, we inserted the entire ‘α’ antigenic determinant amino acids (aa) 119–152 of HBsAg into the truncated HBc (aa 1–144), between Asp78 and Pro79. Prokaryotic expression showed that the mosaic HBc was mainly in the form of inclusion bodies. After denaturation with urea, it was dialyzed progressively for protein renaturation. We observed that before and after renaturation, mosaic HBc was antigenic as determined by HBsAg ELISA and a lot of viruslike particles were observed after renaturation. Thus, we further purified the mosaic viruslike particles by (NH4)2SO4 precipitation, DEAE chromatography, and Sepharose 4FF chromatography. Negative staining electron microscopy demonstrated the morphology of the viruslike particles. Immunization of Balb/c mice with mosaic particles induced the production of anti-HBs antibody and Th1 cell immune response supported by ELISPOT and CD4/CD8 proportions assay. In conclusion, we constructed mosaic hepatitis core particles displaying the entire ‘α’ antigenic determinant on the surface and laid a foundation for researching therapeutic hepatits B vaccines

  15. Construction and immunological evaluation of truncated hepatitis B core particles carrying HBsAg amino acids 119–152 in the major immunodominant region (MIR)

    Su, Qiudong; Yi, Yao [National Institute for Viral Disease Control and Prevention, China Center for Disease Control and Prevention, Changbai Road 155, Changping District, Beijing 102206 (China); Guo, Minzhuo [Beijing Entry-Exit Inspection and Quarantine Beureau, Tianshuiyuan Lane 6, Chaoyang District, Beijing 100026 (China); Qiu, Feng; Jia, Zhiyuan; Lu, Xuexin; Meng, Qingling [National Institute for Viral Disease Control and Prevention, China Center for Disease Control and Prevention, Changbai Road 155, Changping District, Beijing 102206 (China); Bi, Shengli, E-mail: shengli_bi@163.com [National Institute for Viral Disease Control and Prevention, China Center for Disease Control and Prevention, Changbai Road 155, Changping District, Beijing 102206 (China)

    2013-09-13

    Highlights: •The conformational HBV neutralization antigen domain was successfully displayed on the surface of truncated HBc particles. •Appropriate dialysis procedures to support the renaturing environment for the protein refolding. •Efficient purification procedures to obtain high purity and icosahedral particles of mosaic HBV antigen. •Strong immune responses not only including neutralization antibody response but also Th1 cell response were induced in mice. -- Abstract: Hepatitis B capsid protein expressed in Escherichia coli can reassemble into icosahedral particles, which could strongly enhance the immunogenicity of foreign epitopes, especially those inserted into its major immunodominant region. Herein, we inserted the entire ‘α’ antigenic determinant amino acids (aa) 119–152 of HBsAg into the truncated HBc (aa 1–144), between Asp{sup 78} and Pro{sup 79}. Prokaryotic expression showed that the mosaic HBc was mainly in the form of inclusion bodies. After denaturation with urea, it was dialyzed progressively for protein renaturation. We observed that before and after renaturation, mosaic HBc was antigenic as determined by HBsAg ELISA and a lot of viruslike particles were observed after renaturation. Thus, we further purified the mosaic viruslike particles by (NH{sub 4}){sub 2}SO{sub 4} precipitation, DEAE chromatography, and Sepharose 4FF chromatography. Negative staining electron microscopy demonstrated the morphology of the viruslike particles. Immunization of Balb/c mice with mosaic particles induced the production of anti-HBs antibody and Th1 cell immune response supported by ELISPOT and CD4/CD8 proportions assay. In conclusion, we constructed mosaic hepatitis core particles displaying the entire ‘α’ antigenic determinant on the surface and laid a foundation for researching therapeutic hepatits B vaccines.

  16. Two new coordination polymers constructed by naphthalene-1,4-dicarboxylic acid and 2,4-diamino-6-methyl-triazine

    Two new transition metal coordination complexes, ([MnO(nda)](H2dmt)(H2O))n (1), [Ag5(nda)2.5(dmt)]n (2), (H2nda=naphthalene-1,4-dicarboxylic acid, dmt=2,4-diamine-6-methyl-1,3,5-triazine) have been hydrothermally synthesized by the reactions of H2nda and dmt with the homologous MnCl2·4H2O and AgNO3, respectively, and characterized by single-crystal X-ray diffraction, IR spectra, elemental analysis, thermogravimetric analysis (TGA). The compound 1 exhibits a 3D network comprising 1D metal chain (MnO(CO2)2)n connected by the ligand nda2−, featuring a four-connected uninodal diamond -like topology. In compound 2, it is firstly observed that decanuclear silver units as secondary building units to construct 3D network by the ligands dmt and nda2−, with a rare 2-nodal (3,8)-connected tfz-d topology ((43)2(46.618.84)). The interactions within each Mn(II)—Mn(II) pair of compound 1 are antiferromagnetic (g=2.07, J=−1.42(1) cm−1, zj′=−0.73(2) cm−1). In addition, compound 2 exhibits photoluminescent property at about 472 nm (λex=394 nm). - Graphical abstract: Two new transition metal coordination complexes 1–2 have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction, IR spectra, elemental analysis thermogravimetric analysis (TGA). Highlights: • The compound 1 exhibits a 3D network with four-connected uninodal diamond-like topology. • The first 3D network of 2 with a rare tfz-d topology consists of decanuclear silver clusters as secondary building units. • The magnetic measurement indicates the compound 1 shows antiferromagnetic interactions. • The photoluminescent property of 2 has been measured

  17. Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids to Five-, Six-, and Seven-Membered β-Substituted Cyclic Enones: Enantioselective Construction of All-Carbon Quaternary Stereocenters

    Kikushima, Kotaro

    2011-05-11

    The first enantioselective Pd-catalyzed construction of all-carbon quaternary stereocenters via 1,4-addition of arylboronic acids to β-substituted cyclic enones is reported. Reaction of a wide range of arylboronic acids and cyclic enones using a catalyst prepared from Pd(OCOCF(3))(2) and a chiral pyridinooxazoline ligand yields enantioenriched products bearing benzylic stereocenters. Notably, this transformation is tolerant to air and moisture, providing a practical and operationally simple method of synthesizing enantioenriched all-carbon quaternary stereocenters.

  18. Availability of Amino Acids Extends Chronological Lifespan by Suppressing Hyper-Acidification of the Environment in Saccharomyces cerevisiae.

    Yo Maruyama

    Full Text Available The chronological lifespan of Saccharomyces cerevisiae represents the duration of cell survival in the postdiauxic and stationary phases. Using a prototrophic strain derived from the standard auxotrophic laboratory strain BY4742, we showed that supplementation of non-essential amino acids to a synthetic defined (SD medium increases maximal cell growth and extends the chronological lifespan. The positive effects of amino acids can be reproduced by modulating the medium pH, indicating that amino acids contribute to chronological longevity in a cell-extrinsic manner by alleviating medium acidification. In addition, we showed that the amino acid-mediated effects on extension of chronological longevity are independent of those achieved through a reduction in the TORC1 pathway, which is mediated in a cell-intrinsic manner. Since previous studies showed that extracellular acidification causes mitochondrial dysfunction and leads to cell death, our results provide a path to premature chronological aging caused by differences in available nitrogen sources. Moreover, acidification of culture medium is generally associated with culture duration and cell density; thus, further studies are required on cell physiology of auxotrophic yeast strains during the stationary phase because an insufficient supply of essential amino acids may cause alterations in environmental conditions.

  19. Two new coordination polymers constructed by naphthalene-1,4-dicarboxylic acid and 2,4-diamino-6-methyl-triazine

    Li, Yamin, E-mail: liyamin@henu.edu.cn [Institute of Molecular and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004 (China); Xiao, Changyu [Institute of Molecular and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004 (China); Zhang, Xudong [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Xu, Yanhui [Department of Medical Imaging, Bethune Medical Non-Commissioned Officer' s, College, Shijiazhuang, Hebei 050081 (China); Li, Junrui; Lun, Huijie; Chen, Qi [Institute of Molecular and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004 (China)

    2013-08-15

    Two new transition metal coordination complexes, ([MnO(nda)](H{sub 2}dmt)(H{sub 2}O)){sub n} (1), [Ag{sub 5}(nda){sub 2.5}(dmt)]{sub n} (2), (H{sub 2}nda=naphthalene-1,4-dicarboxylic acid, dmt=2,4-diamine-6-methyl-1,3,5-triazine) have been hydrothermally synthesized by the reactions of H{sub 2}nda and dmt with the homologous MnCl{sub 2}·4H{sub 2}O and AgNO{sub 3}, respectively, and characterized by single-crystal X-ray diffraction, IR spectra, elemental analysis, thermogravimetric analysis (TGA). The compound 1 exhibits a 3D network comprising 1D metal chain (MnO(CO{sub 2}){sub 2}){sub n} connected by the ligand nda{sup 2−}, featuring a four-connected uninodal diamond -like topology. In compound 2, it is firstly observed that decanuclear silver units as secondary building units to construct 3D network by the ligands dmt and nda{sup 2−}, with a rare 2-nodal (3,8)-connected tfz-d topology ((4{sup 3}){sub 2}(4{sup 6}.6{sup 18}.8{sup 4})). The interactions within each Mn(II)—Mn(II) pair of compound 1 are antiferromagnetic (g=2.07, J=−1.42(1) cm{sup −1}, zj′=−0.73(2) cm{sup −1}). In addition, compound 2 exhibits photoluminescent property at about 472 nm (λ{sub ex}=394 nm). - Graphical abstract: Two new transition metal coordination complexes 1–2 have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction, IR spectra, elemental analysis thermogravimetric analysis (TGA). Highlights: • The compound 1 exhibits a 3D network with four-connected uninodal diamond-like topology. • The first 3D network of 2 with a rare tfz-d topology consists of decanuclear silver clusters as secondary building units. • The magnetic measurement indicates the compound 1 shows antiferromagnetic interactions. • The photoluminescent property of 2 has been measured.

  20. Stable Isotope Labeling by Amino Acids in Cell Culture (SILAC) Applied to Quantitative Proteomics of Bacillus subtilis

    Soufi, Boumediene; Kumar, C.; Gnad, F.;

    2010-01-01

    We applied stable isotope labeling by amino acids in cell culture (SILAC) to large-scale quantitative proteomics analyses of the model bacterium Bacillus subtilis in two physiological conditions: growth on succinate and growth under phosphate starvation. Using a B. subtilis strain auxotrophic for...... most comprehensive quantitative proteomics studies in bacteria, covering more than 75% of the B. subtilis genes expressed in the log phase of growth. Furthermore, we detect and quantify dynamics of 35 Ser/Thr/Tyr phosphorylation sites under growth on succinate, and 10 phosphorylation sites under...

  1. Engineering of FRT-lacZ fusion constructs: induction of the Pseudomonas aeruginosa fadAB1 operon by medium and long chain-length fatty acids

    Son, Mike S.; Nguyen, David T.; Kang, Yun (Kenneth); Hoang, Tung T.

    2008-01-01

    Without prior knowledge of the promoters of various genes in bacteria, it can be difficult to study gene regulation using reporter-gene fusions. Regulation studies of promoters are ideal at their native locus, which do not require prior knowledge of promoter regions. Based on a previous study with FRT-lacZ-KmR constructs, we constructed two novel FRT-lacZ-GmR plasmids. This allows easy engineering of P. aeruginosa reporter-gene fusions, post-mutant construction with the Flp-FRT system. We dem...

  2. Construction management

    Pellicer, Eugenio; Teixeira, José C; Moura, Helder P; Catalá, Joaquín

    2014-01-01

    The management of construction projects is a wide ranging and challenging discipline in an increasingly international industry, facing continual challenges and demands for improvements in safety, in quality and cost control, and in the avoidance of contractual disputes. Construction Management grew out of a Leonardo da Vinci project to develop a series of Common Learning Outcomes for European Managers in Construction. Financed by the European Union, the project aimed to develop a library of basic materials for developing construction management skills for use in a pan-European context. Focused exclusively on the management of the construction phase of a building project from the contractor's point of view, Construction Management covers the complete range of topics of which mastery is required by the construction management professional for the effective delivery of new construction projects. With the continued internationalisation of the construction industry, Construction Management will be required rea...

  3. Lambda gpP-DnaB Helicase Sequestration and gpP-RpoB Associated Effects: On Screens for Auxotrophs, Selection for Rif(R), Toxicity, Mutagenicity, Plasmid Curing.

    Hayes, Sidney; Wang, Wen; Rajamanickam, Karthic; Chu, Audrey; Banerjee, Anirban; Hayes, Connie

    2016-01-01

    The bacteriophage lambda replication initiation protein P exhibits a toxic effect on its Escherichia coli (E. coli) host, likely due to the formation of a dead-end P-DnaB complex, sequestering the replicative DnaB helicase from further activity. Intracellular expression of P triggers SOS-independent cellular filamentation and rapidly cures resident ColE1 plasmids. The toxicity of P is suppressed by alleles of P or dnaB. We asked whether P buildup within a cell can influence E. coli replication fidelity. The influence of P expression from a defective prophage, or when cloned and expressed from a plasmid was examined by screening for auxotrophic mutants, or by selection for rifampicin resistant (Rif(R)) cells acquiring mutations within the rpoB gene encoding the β-subunit of RNA polymerase (RNAP), nine of which proved unique. Using fluctuation assays, we show that the intracellular expression of P evokes a mutator effect. Most of the Rif(R) mutants remained P(S) and localized to the Rif binding pocket in RNAP, but a subset acquired a P(R) phenotype, lost sensitivity to ColE1 plasmid curing, and localized outside of the pocket. One P(R) mutation was identical to rpo*Q148P, which alleviates the UV-sensitivity of ruv strains defective in the migration and resolution of Holliday junctions and destabilizes stalled RNAP elongation complexes. The results suggest that P-DnaB sequestration is mutagenic and supports an earlier observation that P can interact with RNAP. PMID:27338450

  4. The potential of 3-dimensional construct engineered from poly(lactic-co-glycolic acid)/fibrin hybrid scaffold seeded with bone marrow mesenchymal stem cells for in vitro cartilage tissue engineering.

    Abdul Rahman, Rozlin; Mohamad Sukri, Norhamiza; Md Nazir, Noorhidayah; Ahmad Radzi, Muhammad Aa'zamuddin; Zulkifly, Ahmad Hafiz; Che Ahmad, Aminudin; Hashi, Abdurezak Abdulahi; Abdul Rahman, Suzanah; Sha'ban, Munirah

    2015-08-01

    Articular cartilage is well known for its simple uniqueness of avascular and aneural structure that has limited capacity to heal itself when injured. The use of three dimensional construct in tissue engineering holds great potential in regenerating cartilage defects. This study evaluated the in vitro cartilaginous tissue formation using rabbit's bone marrow mesenchymal stem cells (BMSCs)-seeded onto poly(lactic-co-glycolic acid) PLGA/fibrin and PLGA scaffolds. The in vitro cartilaginous engineered constructs were evaluated by gross inspection, histology, cell proliferation, gene expression and sulphated glycosaminoglycan (sGAG) production at week 1, 2 and 3. After 3 weeks of culture, the PLGA/fibrin construct demonstrated gross features similar to the native tissue with smooth, firm and glistening appearance, superior histoarchitectural and better cartilaginous extracellular matrix compound in concert with the positive glycosaminoglycan accumulation on Alcian blue. Significantly higher cell proliferation in PLGA/fibrin construct was noted at day-7, day-14 and day-21 (p<0.05 respectively). Both constructs expressed the accumulation of collagen type II, collagen type IX, aggrecan and sox9, showed down-regulation of collagen type I as well as produced relative sGAG content with PLGA/fibrin construct exhibited better gene expression in all profiles and showed significantly higher relative sGAG content at each time point (p<0.05). This study suggested that with optimum in vitro manipulation, PLGA/fibrin when seeded with pluripotent non-committed BMSCs has the capability to differentiate into chondrogenic lineage and may serve as a prospective construct to be developed as functional tissue engineered cartilage. PMID:26100682

  5. Design and characterization of auxotrophy-based amino acid biosensors.

    Felix Bertels

    Full Text Available Efficient and inexpensive methods are required for the high-throughput quantification of amino acids in physiological fluids or microbial cell cultures. Here we develop an array of Escherichia coli biosensors to sensitively quantify eleven different amino acids. By using online databases, genes involved in amino acid biosynthesis were identified that - upon deletion - should render the corresponding mutant auxotrophic for one particular amino acid. This rational design strategy suggested genes involved in the biosynthesis of arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, threonine, tryptophan, and tyrosine as potential genetic targets. A detailed phenotypic characterization of the corresponding single-gene deletion mutants indeed confirmed that these strains could neither grow on a minimal medium lacking amino acids nor transform any other proteinogenic amino acid into the focal one. Site-specific integration of the egfp gene into the chromosome of each biosensor decreased the detection limit of the GFP-labeled cells by 30% relative to turbidometric measurements. Finally, using the biosensors to determine the amino acid concentration in the supernatants of two amino acid overproducing E. coli strains (i.e. ΔhisL and ΔtdcC both turbidometrically and via GFP fluorescence emission and comparing the results to conventional HPLC measurements confirmed the utility of the developed biosensor system. Taken together, our study provides not only a genotypically and phenotypically well-characterized set of publicly available amino acid biosensors, but also demonstrates the feasibility of the rational design strategy used.

  6. Usability Constructs

    Hertzum, Morten; Clemmesen, Torkil; Hornbæk, Kasper Anders Søren;

    2007-01-01

    Whereas research on usability predominantly employs universal definitions of the aspects that comprise usability, people experience their use of information systems through personal constructs. Based on 48 repertory-grid interviews, this study investigates how such personal constructs are affecte...

  7. Construction practice

    One has elaborated a virtual computer model (VRC) of construction of the AP1000 project reactor to demonstrate its viability, to improve the NPP project making it more easy for construction with simultaneous reduction of time, costs and risk of construction. The approach ensured time sequence of the 3-D visualization of NPP at the construction stages. The VRC ensures optimization of scheme implementation time period and specifies the basic costs. The VRC application offers essential advantages when planning construction of a nuclear power facility

  8. Construction supervision in construction project

    Struna, Ervin

    2012-01-01

    Every construction project is a unique, complex process. Every completed structure is permanent act into space, and has therefore substantial influence upon social and natural environment. As a consequence, it is essential to provide professional supervision of the construction process that will ensure conformity of the construction with the project documentation and the building permit. The purpose of the thesis is to present the role of the construction supervision and the work of the s...

  9. Seq2Logo: a method for construction and visualization of amino acid binding motifs and sequence profiles including sequence weighting, pseudo counts and two-sided representation of amino acid enrichment and depletion

    Thomsen, Martin Christen Frølund; Nielsen, Morten

    2012-01-01

    Seq2Logo is a web-based sequence logo generator. Sequence logos are a graphical representation of the information content stored in a multiple sequence alignment (MSA) and provide a compact and highly intuitive representation of the position-specific amino acid composition of binding motifs, active...... sites, etc. in biological sequences. Accurate generation of sequence logos is often compromised by sequence redundancy and low number of observations. Moreover, most methods available for sequence logo generation focus on displaying the position-specific enrichment of amino acids, discarding the equally...... valuable information related to amino acid depletion. Seq2logo aims at resolving these issues allowing the user to include sequence weighting to correct for data redundancy, pseudo counts to correct for low number of observations and different logotype representations each capturing different aspects...

  10. Three silver-based complexes constructed from organic carboxylic acid and 4,4‧-bipyridine-like ligands: Syntheses, structures and photocatalytic properties

    Wang, Chong-chen; Jing, Huan-ping; Wang, Peng

    2014-09-01

    The reactions of AgNO3 with combinations of 4,4‧-bipyridine (bpy)/1,2-di(4-pyridyl)ethylene (dpe), and 5-aminophthalic acid (H2ap)/2,6-Naphthalenedicarboxylic acid (H2npdc)/4,4‧-stilbenedicarboxylic acid (H2sbdc) in aqueous alcohol/ammonia at room temperature produce crystals of [Ag4(bpy)4](ap)2·11H2O (1), [Ag2(bpy)2](npdc)·2H2O (2) and [Ag2(dpe)1.5(sbdc)0.5](sbdc)0.5·7H2O (3). All complexes 1, 2 and 3 consist of 1D infinite silver-ligand cationic chains, interspersed with organic carboxylate anions that provide charge compensation in the crystal structures. The lattice water molecules are situated among the framework of the crystal structure and show rich hydrogen-bonding interactions, which serve to orientate of the organic carboxylate anions in the crystal packing, while the presence of Ag⋯N and Ag⋯Ag contacts strengthens the frameworks. In addition, complexes 1-3 exhibit good photocatalytic activities for dye decolorization under UV light.

  11. Test Research on Compound Polycarboxylic Acid Admixture During Winter Construction%复合型聚羧酸外加剂在冬期施工应用中的试验研究

    杨建国; 王明明; 李忠雨; 娄维萍; 马学伟

    2011-01-01

    Based on the E bid section in one stage of Jinwan Square, reasonable test method is selected during the winter construction of compound polycarboxylic acid admixture.Besides, effects of different concrete mix proportions are studied on the concrete workability, and effects of different maintenance conditions are researched on concrete compressive strength.The optimum mixing amount is chosen by analyzing data to be applied in the engineering.Good economic benefit is obtained.The results show that compound polycarboxylic acid admixture can not only enhance mechanical performance of concrete, but also offer the convenient construction technology.%结合津湾广场一期E标段工程,在聚羧酸外加剂冬期施工中,恰当选取试验方法,考虑不同混凝土配合比对混凝土工作性的影响以及不同养护条件对混凝土抗压强度的影响.经过数据分析,优选了聚羧酸的最佳掺量,并应用于工程中,取得了良好的经济效果.结果表明:复合型聚羧酸外加剂不仅能提高混凝土的力学性能,而且能提供简便易行的施工工艺.

  12. Yeast mutants auxotrophic for choline or ethanolamine.

    Atkinson, K D; Jensen, B.; Kolat, A I; Storm, E M; Henry, S. A.; Fogel, S

    1980-01-01

    Three mutants of the yeast Saccharomyces cerevisiae which require exogenous ethanolamine or choline were isolated. The mutants map to a single locus (cho1) on chromosome V. The lipid composition suggests that cho1 mutants do not synthesize phosphatidylserine under any growth conditions. If phosphatidylethanolamine or phosphatidylcholine, which are usually derived from phosphatidylserine, were synthesized from exogenous ethanolamine or choline, the mutants grew and divided relatively normally....

  13. Torus Construction

    Valluri, Monica; Merritt, David

    1999-01-01

    The maximally compact representation of a regular orbit is in terms of its action-angle variables. Computing the map between a trajectory's Cartesian coordinates and its action-angle variables is called torus construction. This article reviews various approaches to torus construction and their application to galactic dynamics.

  14. Superstring construction

    1989-01-01

    The book includes a selection of papers on the construction of superstring theories, mainly written during the years 1984-1987. It covers ten-dimensional supersymmetric and non-supersymmetric strings, four-dimensional heterotic strings and four-dimensional type-II strings. An introduction to more recent developments in conformal field theory in relation to string construction is provided.

  15. Construction Management.

    Abbott, James F.

    This article provides a detailed discussion of a team approach to building that involves a construction manager, an architect, and a contractor. Bidding methods are outlined; the major components in construction management -- value engineering and fast track scheduling -- and the use of performance specifications are discussed. The construction…

  16. Bipolar battery construction

    Rippel, Wally E. (Inventor); Edwards, Dean B. (Inventor)

    1981-01-01

    A lightweight, bipolar battery construction for lead acid batteries in which a plurality of thin, rigid, biplates each comprise a graphite fiber thermoplastic composition in conductive relation to lead stripes plated on opposite flat surfaces of the plates, and wherein a plurality of nonconductive thermoplastic separator plates support resilient yieldable porous glass mats in which active material is carried, the biplates and separator plates with active material being contained and maintained in stacked assembly by axial compression of the stacked assembly. A method of assembling such a bipolar battery construction.

  17. Construction management

    PEFP, Proton Engineering Frontier Project, puts its aim to building 100MeV 20mA linear proton accelerator which is national facility for NT, BT, IT, and future technologies, expected to boost up the national industry competitiveness. This R and D, Construction Management is in charge of the supportive works as site selection, architecture and engineering of conventional facilities, and overall construction management. The major goals of this work are as follows: At first, architecture and engineering of conventional facilities. Second, construction management, audit and inspection on construction of conventional facilities. Lastly, cooperation with the project host organization for adjusting technical issues of overall construction. In this research, We made a conceptual design, basic design and detail design of conventional facilities. Also, we made the engineering support for host site construction as follows : selection of project host organization and host site selection, construction technical work for project host organization and procedure management and impact analysis on the delay of project site selection

  18. Construction mathematics

    Virdi, Surinder

    2006-01-01

    Taking a starting point below that of GCSE level, by assuming no prior mathematical knowledge, Surinder Virdi and Roy Baker take the reader step by step through the mathematical requirements for Level 2 and 3 Building and Construction courses.Unlike the majority of basic level maths texts available, this book focuses exclusively on mathematics as it is applied in actual construction practice. As such, topics specific to the construction industry are presented, as well as essential areas for Level 2 craft NVQs - for example, costing calculations, labor costs, cost of materials and setting out o

  19. Construction of two Cd(II) complexes by flexible adipic acid plus 2-((benzoimidazol-yl)methyl)-1H-tetrazole ligand

    Duan, Wanlu; Zhang, Yuhong; Wang, Xiuxiu; Meng, Xiangru

    2015-10-01

    Two new complexes with the formulas [Cd(bimt)(adi)]n (1) and {[Cd(bimt)(adi)0.5Br]·H2O}n (2) were synthesized through reactions of 2-((benzoimidazol-yl)methyl)-1H-tetrazole (bimt) with Cd(II) salts in the presence of adipic acid (H2adi). Single crystal X-ray analysis reveals that complex 1 shows a 1D chain structure in which adipate ligand coordinates to Cd(II) ions with μ3-bridging mode. Complex 2 displays a 2D layer structure with 4-connected (44·62) topology in which adipate ligand coordinates to Cd(II) ions with μ2-bridging mode. These results reveal that the versatile coordination modes of adipate ligands play an important role in controlling the structures of the complexes. In addition, their IR spectra, element analyses, PXRD patterns and luminescent properties are investigated.

  20. Worldwide construction

    The paper lists major construction projects in worldwide processing and pipelining, showing capacities, contractors, estimated costs, and time of construction. The lists are divided into refineries, petrochemical plants, sulfur recovery units, gas processing plants, pipelines, and related fuel facilities. This last classification includes cogeneration plants, coal liquefaction and gasification plants, biomass power plants, geothermal power plants, integrated coal gasification combined-cycle power plants, and a coal briquetting plant

  1. 基于PTS缺陷型大肠杆菌构建莽草酸生产菌%Construction of shikimic acid-producing engineered Escherichia coli strains based on ptsHIcrr mutants

    邹永康; 周军智; 孙旭; 蔡亚非; 戴红梅; 李树龙; 周长林; 方宏清

    2011-01-01

    对大肠杆菌芳香族氨基酸合成途径进行代谢流改造,以实现高效的生物制备莽草酸.以磷酸烯醇式丙酮酸-糖磷酸转移酶系统(PTS系统)敲除菌DH5αΔptsHIcrr(DHP)为基础,特异性敲除aroL,ydiB基因并转入受阿拉伯糖诱导表达的T7-RNA聚合酶基因,最终构建一系列产莽草酸宿主菌.再将aroE、aroB、tktA、glk、aroF组成的系列基因串联起来置于质粒上,在T7启动子控制下表达,经摇瓶培养检测得知,不同重组菌产莽草酸能力与对照相比均有明显提高,其中DHPYA-T7/pAOC-TGEFB菌株产量最高,可达到392 mg/L.为进一步构建高表达莽草酸工程菌奠定基础.%Metabolic engineering for aromatic amino acid biosynthesis pathway in Escherichia coli to acquire high-level biosynthesis of shikimic acid was reported. Knockout of aroL, ydiB genes and knock-in of T7-RNA-Polymerase gene which expression was controlled by L-arabinose based on the initial strain DH5α△ptsHlcrr (DHP), resulted in a series of shikimic acid-producing host strains. A series of tandem genes consisting of aroE, aroB, tktA, glk or aroFfbr were controlled by T7 promoter on plasmids were transformed into these host strains. According to the concentration of shikimic acid in shake-flask culture, all the engineered strains displayed high-potentiality compared to the control strain DHP, and the strain DHPYA-T7/pAOC-TGEFB synthesized the highest yield of 392 mg/L of shikimic acid. This study layed a strong foundation for constructing a high-level shikimic acid-producing engineered strain.

  2. 3,4,9,10-perylenetetracarboxylic acid/hemin nanocomposites act as redox probes and electrocatalysts for constructing a pseudobienzyme-channeling amplified electrochemical aptasensor.

    Yuan, Yali; Yuan, Ruo; Chai, Yaqin; Zhuo, Ying; Gan, Xianxue; Bai, Lijuan

    2012-10-29

    A simple wet-chemical strategy for the synthesis of 3,4,9,10-perylenetetracarboxylic acid (PTCA)/hemin nanocomposites through π-π interactions is demonstrated. Significantly, the hemin successfully conciliates PTCA redox activity with a pair of well-defined redox peaks and intrinsic peroxidase-like activity, which provides potential application of the PTCA self-derived redox activity as redox probes. Additionally, PTCA/hemin nanocomposites exhibit a good membrane-forming property, which not only avoids the conventional fussy process for redox probe immobilization, but also reduces the participation of the membrane materials that act as a barrier of electron transfer. On the basis of these unique properties, a pseudobienzyme-channeling amplified electrochemical aptasensor is developed that is coupled with glucose oxidase (GOx) for thrombin detection by using PTCA/hemin nanocomposites as redox probes and electrocatalysts. With the addition of glucose to the electrolytic cell, the GOx on the aptasensor surface bioelectrocatalyzed the reduction of glucose to produce H(2)O(2), which in turn was electrocatalyzed by the PTCA/hemin nanocomposites. Cascade schemes, in which an enzyme is catalytically linked to another enzyme, can produce signal amplification and therefore increase the biosensor sensitivity. As a result, a linear relationship for thrombin from 0.005 to 20 nM and a detection limit of 0.001 nM were obtained. PMID:23001991

  3. Construction safety

    Li, Rita Yi Man

    2013-01-01

    A close-to-ideal blend of suburb and city, speedy construction of towers of Babylon, the sparkling proportion of glass and steel buildings’ facade at night showcase the wisdom of humans. They also witness the footsteps, sweats and tears of architects and engineers. Unfortunately, these signatures of human civilizations are swathed in towering figures of construction accidents. Fretting about these on sites, different countries adopt different measures on sites. This book firstly sketches the construction accidents on sites, followed by a review on safety measures in some of the developing countries such as Bermuda, Egypt, Kuwait and China; as well as developed countries, for example, the United States, France and Singapore. It also highlights the enormous compensation costs with the courts’ experiences in the United Kingdom and Hong Kong.

  4. Construction Physics

    Bertelsen, Sven; Henrich, Guilherme; Koskela, Lauri; Rooke, John

    2007-01-01

    At the 14th annual conference in the International Group for Lean Construction in 2006 the authors presented the concept of construction as a process being fed by a number of flows out of which one is the critical one deciding the speed with which the process takes place. This contribution takes the idea further and sets out by discussing production in general and the underlying mental flow models associated with this understanding. It then suggests a new model for the understanding of the na...

  5. Construction work

    2004-01-01

    Construction work on building 179 will start on the 16th February 2004 and continue until November 2004. The road between buildings 179 and 158 will temporarily become a one way street from Route Democrite towards building 7. The parking places between buildings 179 and 7 will become obsolete. The ISOLDE collaboration would like to apologize for any inconveniences.

  6. pH非敏感型自交联共轭亚油酸囊泡的构建和表征%Construction and Characterization of a Novel pH-insensitive Self-crosslinked Ufasome of Conjugated Linoleic Acid

    樊晔; 方云; 高迪

    2014-01-01

    Conjugated linoleic acid( CLA) was employed as a molecular building block to construct a novel pH-insensitive fatty acid vesicle(FAV). First, CLA was semi-synthesized from linoleic acid through alkali isomerization. Subsequently, the ufasome(unsaturated fatty acid liposome) of CLA was self-assembled from the CLA molecules together with the CLA ions in response to pH, and a novel pH-insensitive FAV, the self-crosslinked-CLA FAV, was prepared by chemical tethering the CLA-ufasome through UV irradiation. The sui-table pH ranges and the CLA concentrations were determined by acid-base titration and surface tension mea-surement. The morphology of the self-crosslinked-CLA FAV was imaged by transmission electro microscopy ( TEM) and the pH-insensitive characteristic of the self-crosslinked-CLA FAV was tested by dynamic light scattering ( DLS ) . The experimental results indicated that the self-crosslinked-CLA FAV with diameter of 10-20 nm and wall thickness of 2.0 nm was obtained through a two-step procedure. At first, the CLA-ufa-some formed using the CLA species as a molecular building block at pH=8.6 and CLA concentration of 3 mmol/L, and then followed by UV irradiation self-crosslinking for 2.5 h. It was verified by DLS data that the self-crosslinked-CLA FAV is pH-insensitive in almost all pH ranges. Finally, the in vitro release results of 5-fluorouracil from the self-crosslinked-CLA FAV showed that the process was slow and sustainable.%以共轭亚油酸( Conjugated linoleic acid, CLA)为构造pH非敏感型脂肪酸囊泡( Fatty acid vesicle, FAV)的分子砌块,通过碱异构化法从亚油酸半合成CLA,然后采用pH刺激响应自组装法获得CLA的不饱和脂肪酸囊泡( Ufasome),采用紫外辐照诱导方式对CLA-ufasome实施囊泡内化学绑定,获得一种新的pH非敏感型FAV.通过酸碱滴定和表面张力实验确定CLA-ufasome形成的适宜pH范围和浓度,利用透射电子显微镜( TEM)表征了自交联CLA的FAV的

  7. Modelling Constructs

    Kindler, Ekkart

    2009-01-01

    There are many different notations and formalisms for modelling business processes and workflows. These notations and formalisms have been introduced with different purposes and objectives. Later, influenced by other notations, comparisons with other tools, or by standardization efforts, these...... notations have been extended in order to increase expressiveness and to be more competitive. This resulted in an increasing number of notations and formalisms for modelling business processes and in an increase of the different modelling constructs provided by modelling notations, which makes it difficult...... to compare modelling notations and to make transformations between them. One of the reasons is that, in each notation, the new concepts are introduced in a different way by extending the already existing constructs. In this chapter, we go the opposite direction: We show that it is possible to add...

  8. Constructive Interactions

    Lemoisson, Philippe; Cerri, Stefano A.; Mahe, Serge-André; Sallantin, Jean

    2003-01-01

    The new paradigm of "knowledge construction using experiential based and collaborative learning approaches" is an outstanding opportunity for interdisciplinary research. This document is an attempt to introduce and exemplify as much as possible using the lexicon of "social sciences", considerations and tools belonging to "artificial intelligence" (eg.:the machine learning tradition). In the paper we first draw a conceptual framework for rational agents in conversational interaction; then we u...

  9. Constructing Catalonia

    Bill Phillips

    2009-01-01

    Full Text Available Catalonia, in common with other nations, has long b een concerned with the question of identity and difference. Its problemati c relationship with Spain has led to an emphasis on differentiating itself from its larger neighbour (if we are to accept, as most Spaniards do not, that Catalonia is not Spain, a s ituation complicated by the loss of the Spanish colonies of Cuba and The Philippines in 189 8, and the Spanish Civil War and subsequent dictatorship from 1936 to 1976. Beginnin g in the late nineteenth century, the construction of a Catalan identity followed a simil ar route to that taken by other European nations such as England, Ireland and, inde ed, Spain, including an emphasis on rural values, activities and the countryside, and t he conversion of specifically local traditions into national past times. It is only in the last ten years or so that this model of Catalan identity has been recognised for what it is – a model constructed and encouraged for and by specific nationalist politica l interests. Ironically, Catalonia’s identity abroad has also been constructed and manip ulated for political purposes, but from quite a different perspective. Orwell’s /Homag e to Catalonia/ (1938 narrates an extremely blinkered version of the Spanish Civil Wa r which has achieved iconic status as a result of cold war politics. Subsequent portra yals of the Spanish Civil War – Valentine Cunningham’s /The Penguin Book of Spanish Civil War Verse/ (ed., Penguin, 1980, or Ken Loach’s 1995 film /Land and F reedom/ base their arguments unquestioningly on /Homage to Catalonia/, perpetuat ing a view of the nation’s recent history that is both reductive and inaccurate

  10. Constructing Costs

    Donner, Henrik af

    2000-01-01

    The economic analysis of building contracts is an unexplored field within Law and Economics. This paper makes an attempt to cast some light over the subject and encourage to more research within the field. The main purpose has been to describe why the actual price in a public construction project often turns out to be higher than the contract price and offer a way of handle that risk. In the paper a model is set up that shows an optimal contract given expectations on actual price and gaps in ...

  11. Syntheses, crystal structures and fluorescent properties of Cd(II), Hg(II) and Ag(I) coordination polymers constructed from 1H-1,2,4-triazole-1-acetic acid

    Three new d10 coordination polymers, namely [Cd(taa)Cl]n1, [Hg(taa)Cl]n2, and [Ag1.5(taa)(NO3)0.5]n3 (taa=1H-1,2,4-triazole-1-acatate anion) have been prepared and characterized by elemental analysis, IR, and single crystal X-ray diffraction. Compound 1 consists of two-dimensional layers constructed by carboxyl-linked helical chains, which are further linked through carboxyl group to generate a unique 3D open framework. Topological analysis reveals that the structure of 1 can be classified as an unprecedented (3,8)-connected network with the Schlaefli symbol (4.52)2(42.58.614.73.8). Compound 2 manifests a doubly interpenetrated decorated α-polonium cubic network with the Schlaefli symbol of (410.62.83). Compound 3 consists of 2D puckered layers made up of Ag centers and taa- bridges. In addition, all of these compounds are photoluminescent in the solid state with spectra that closely resemble those of the ligand precursor. - Graphical abstract: Three new compounds based on 1H-1,2,4-triazole-1-acetic acid and Cd(II), Hg(II) and Ag(I) salts display luminescent properties and may be potential candidates for luminescent materials.

  12. Constructing Brambles

    Chapelle, Mathieu; Mazoit, Frédéric; Todinca, Ioan

    Given an arbitrary graph G and a number k, it is well-known by a result of Seymour and Thomas [22] that G has treewidth strictly larger than k if and only if it has a bramble of order k + 2. Brambles are used in combinatorics as certificates proving that the treewidth of a graph is large. From an algorithmic point of view there are several algorithms computing tree-decompositions of G of width at most k, if such decompositions exist and the running time is polynomial for constant k. Nevertheless, when the treewidth of the input graph is larger than k, to our knowledge there is no algorithm constructing a bramble of order k + 2. We give here such an algorithm, running in {mathcal O}(n^{k+4}) time. For classes of graphs with polynomial number of minimal separators, we define a notion of compact brambles and show how to compute compact brambles of order k + 2 in polynomial time, not depending on k.

  13. A Constructed Wetland: From Monitoring To Action.

    Kowal, Dan

    1998-01-01

    Presents a water-quality monitoring project in a Denver school that has evolved into an experiment using a constructed wetland system to treat the acid-mine drainage from an abandoned gold mine. (PVD)

  14. Synthesis, crystal structure and properties of two 1D nano-chain coordination polymers constructed by lanthanide with pyridine-3,4-dicarboxylic acid and 1,10-phenanthroline

    The hydrothermal reactions of LnCl3.6H2O (Ln=Eu, Tb), pyridine-3,4-dicarboxylic acid (3,4-pydaH2), 1,10-phenthroline (phen) and NaOH in aqueous medium yield two metal-organic hybrid materials, [Eu2(3,4-pyda)3(phen)(H2O).H2O]n (1) and [Tb2(3,4-pyda)3(phen)(H2O).H2O]n (2), respectively. Both compounds have similar topology structure containing one-dimensional nano-chain, which is further assembled into a three-dimensional supramolecular network via π-π stacking interactions and hydrogen bonds. To the best of our knowledge, they represent the first example of nano-chain coordination polymers constructed by 3,4-pydaH2 and chelate heterocylic ligand. Interestingly, the 3,4-pyda anion exhibits three kinds of coordination modes in these complexes. The coordination modes of 3,4-pyda in complexes 1 and 2 have not been observed in other coordination polymers containing 3,4-pyda ligands. Compounds 1 and 2 exhibit strong fluorescent emission bands in the solid state at room temperature. Their magnetic analyses show that they exhibit different magnetic interactions. - Graphical abstract: Two novel lanthanide coordination polymers [M2(pydc)3(phen)(H2O).H2O]n (M=Eu(1) and Tb(2), pydc=pyridine-3,4-dicarboxylate, phen=1,10-phenthroline) have been synthesized and characterized. Both compounds reveal a one-dimensional nano-chain, which is further assembled into a three-dimensional supramolecular network via π-π stacking interactions and hydrogen bonds. Their luminescent and magnetic properties have been investigated

  15. Constructing Aligned Assessments Using Automated Test Construction

    Porter, Andrew; Polikoff, Morgan S.; Barghaus, Katherine M.; Yang, Rui

    2013-01-01

    We describe an innovative automated test construction algorithm for building aligned achievement tests. By incorporating the algorithm into the test construction process, along with other test construction procedures for building reliable and unbiased assessments, the result is much more valid tests than result from current test construction…

  16. Plasmid construction using recombination activity in the fission yeast Schizosaccharomyces pombe.

    Ayako Chino

    Full Text Available BACKGROUND: Construction of plasmids is crucial in modern genetic manipulation. As of now, the common method for constructing plasmids is to digest specific DNA sequences with restriction enzymes and to ligate the resulting DNA fragments with DNA ligase. Another potent method to construct plasmids, known as gap-repair cloning (GRC, is commonly used in the budding yeast Saccharomyces cerevisiae. GRC makes use of the homologous recombination activity that occurs within the yeast cells. Due to its flexible design and efficiency, GRC has been frequently used for constructing plasmids with complex structures as well as genome-wide plasmid collections. Although there have been reports indicating GRC feasibility in the fission yeast Schizosaccharomyces pombe, this species is not commonly used for GRC as systematic studies of reporting GRC efficiency in S. pombe have not been performed till date. METHODOLOGY/PRINCIPAL FINDINGS: We investigated GRC efficiency in S. pombe in this study. We first showed that GRC was feasible in S. pombe by constructing a plasmid that contained the LEU2 auxotrophic marker gene in vivo and showed sufficient efficiency with short homology sequences (>25 bp. No preference was shown for the sequence length from the cut site in the vector plasmid. We next showed that plasmids could be constructed in a proper way using 3 DNA fragments with 70% efficiency without any specific selections being made. The GRC efficiency with 3 DNA fragments was dramatically increased >95% in lig4Delta mutant cell, where non-homologous end joining is deficient. Following this approach, we successfully constructed plasmid vectors with leu1+, ade6+, his5+, and lys1+ markers with the low-copy stable plasmid pDblet as a backbone by applying GRC in S. pombe. CONCLUSIONS/SIGNIFICANCE: We concluded that GRC was sufficiently feasible in S. pombe for genome-wide gene functional analysis as well as for regular plasmid construction. Plasmids with different

  17. Polymer supported sulphanilic acid: A highly efficient and recyclable green heterogeneous catalyst for the construction of 4,5-dihydropyrano[3,2-c]chromenes under solvent-free conditions

    Jashmin P Patel; Jemin R Avalani; Dipak K Raval

    2013-05-01

    Polystyrene divinylbenzene supported sulphanilic acid was prepared, characterized and tested as an acidic catalyst in multicomponent organic synthesis. This is the first report focusing on the development of one-pot solvent-free synthesis of 4,5- dihydropyrano [3,2-c]chromenes under acidic conditions. It proved to be a versatile catalyst for microwave-assisted synthesis of 4,5-dihydropyrano[3,2-c]chromenes. This methodology is mild, high yielding, green and the catalyst could be easily recycled for several times.

  18. Concrete construction engineering handbook

    Nawy, Edward G

    2008-01-01

    Provides coverage of concrete construction engineering and technology. This work features discussions focusing on: the advances in engineered concrete materials; reinforced concrete construction; specialized construction techniques; and, design recommendations for high performance.

  19. High-performance liquid chromatography analysis of naturally occurring D-amino acids in sake.

    Gogami, Yoshitaka; Okada, Kaori; Oikawa, Tadao

    2011-11-01

    We measured all of the D- and L-amino acids in 141 bottles of sakes using HPLC. We used two precolumn derivatization methods of amino acid enantiomer detection with o-phthalaldehyde and N-acetyl-L-cysteine, as well as (+)-1-(9-fluorenyl)ethyl chloroformate/1-aminoadamantane and one postcolumn derivatization method with o-phthalaldehyde and N-acetyl-L-cysteine. We found that the sakes contained the D-amino acids forms of Ala, Asn, Asp, Arg, Glu, Gln, His, Ile, Leu, Lys, Ser, Tyr, Val, Phe, and Pro. We were not able to detect D-Met, D-Thr D-Trp in any of the sakes analyzed. The most abundant D-Ala, D-Asp, and D-Glu ranged from 66.9 to 524.3 μM corresponding to relative 34.4, 12.0, and 14.6% D-enantiomer. The basic parameters that generally determine the taste of sake such as the sake meter value (SMV; "Nihonshudo"), acidity ("Sando"), amino acid value ("Aminosando"), alcohol content by volume, and rice species of raw material show no significant relationship to the D-amino acid content of sake. The brewing water ("Shikomimizu") and brewing process had effects on the D-amino acid content of the sakes: the D-amino acid contents of the sakes brewed with deep-sea water "Kaiyoushinosousui", "Kimoto yeast starter", "Yamahaimoto", and the long aging process "Choukijukusei" are high compared with those of other sakes analyzed. Additionally, the D-amino acid content of sakes that were brewed with the adenine auxotroph of sake yeast ("Sekishoku seishu kobo", Saccharomyces cerevisiae) without pasteurization ("Hiire") increased after storage at 25 °C for three months. PMID:21555255

  20. Amino acids

    Amino acids are organic compounds that combine to form proteins . Amino acids and proteins are the building blocks of life. When proteins are digested or broken down, amino acids are left. The human body uses amino acids ...

  1. Determination of acute lethal and chronic lethal dose thresholds of valproic acid using 3D spheroids constructed from the immortal human hepatocyte cell line HepG2/C3A

    Fey, S. J.; Wrzesinski, K.

    2013-01-01

    describe here a culture system based on 3D spheroid culture of immortal hepatocytes which can determine the toxicity of valproic acid (or structurally or functionally related molecules) in vitro. The spheroids were used to follow changes in ATP production, glucose uptake and adenylate kinase following...

  2. Acid-Mediated N-H/α,β-C(sp(3))-H Trifunctionalization of Pyrrolidine: Intermolecular [3 + 2] Cycloaddition for the Construction of 2,3-Dihydro-1H-Pyrrolizine Derivatives.

    Zheng, Kai-Lu; Shu, Wen-Ming; Ma, Jun-Rui; Wu, Yan-Dong; Wu, An-Xin

    2016-08-01

    A one-pot acid-mediated reaction has been developed for the N-H/α,β-C(sp(3))-H trifunctionalization of pyrrolidine without any metallic reagents or external oxidants. This reaction involves the intermolecular [3 + 2] cycloaddition of in situ-generated azomethine ylides with acrylic esters to provide facile access to 2,3-dihydro-1H-pyrrolizine derivatives in high yields under mild conditions. PMID:27396906

  3. USAID Construction Assessment

    US Agency for International Development — The USAID construction assessment is a survey of the character, scope, value and management of construction activities supported by USAID during the period from...

  4. Professional entrepreneurial identity construction

    Ramsgaard, Michael Breum

    2014-01-01

    The present study investigates the construction of a professional identity as an entrepreneur in a sample of people with educational background in nutrition and health. The study examines the connection between professional identity construction and entrepreneurial business emergence using...

  5. Organizational Behaviour in Construction

    Kreiner, Kristian

    2013-01-01

    Review of: Organizational Behaviour in Construction / Anthony Walker (Wiley-Blackwell,2011 336 pp)......Review of: Organizational Behaviour in Construction / Anthony Walker (Wiley-Blackwell,2011 336 pp)...

  6. NANOTECHNOLOGY IN CONSTRUCTION

    Saeli, .

    2011-01-01

    Nanotechnology, which has a vast number of possibilities in construction, ranging from energy conservation and coatings to structural enhancement and stress monitoring, has not yet made an important difference in construction compared to other major industries even when there has been a big progress in awareness and investigation in the last years. Nanotechnology has the potential to extend the limits of construction bringing new and enhanced products that can foster the construction activity...

  7. Construction Management : Study Book

    Ilveskoski, Olli; Niittymäki, Seppo

    2015-01-01

    This publication is a summary of the Construction Management course handscript. The objective is that as the students gets involved with the Construction Management of Building Projects they will learn Construction Management topics like Building Process, Production planning, Quantity Take Off, Cost Estimation, Scheduling, Work Safety and Quality Control. The study book has been in use in Construction Management courses in Häme University of Applied Sciences.

  8. Track Construction Manual.

    Banke, Ron; Di Gennaro, Guy; Ediger, Rick; Garner, Lanny; Hersom, Steve; Miller, Jack; Nemeth, Ron; Petrucelli, Jim; Sierks, Donna; Smith, Don; Swank, Kevin; West, Kevin

    This book establishes guidelines for the construction and maintenance of tracks by providing information for building new tracks or upgrading existing tracks. Subjects covered include running track planning and construction, physical layout, available surfaces, and maintenance. General track requirements and construction specifications are…

  9. GPS Applications in Construction

    Stranger, J. W.

    2012-01-01

    This session will explore the use of GPS technology in the construction engineering aspects of highway projects. Discussion will include control of line and grade for construction equipment and how the state inspector can verify the construction is according to plans without physical surveying stakes.

  10. Engineering biotin prototrophic Corynebacterium glutamicum strains for amino acid, diamine and carotenoid production.

    Peters-Wendisch, P; Götker, S; Heider, S A E; Komati Reddy, G; Nguyen, A Q; Stansen, K C; Wendisch, V F

    2014-12-20

    The Gram-positive Corynebacterium glutamicum is auxotrophic for biotin. Besides the biotin uptake system BioYMN and the transcriptional regulator BioQ, this bacterium possesses functional enzymes for the last three reactions of biotin synthesis starting from pimeloyl-CoA. Heterologous expression of bioF from the Gram-negative Escherichia coli enabled biotin synthesis from pimelic acid added to the medium, but expression of bioF together with bioC and bioH from E. coli did not entail biotin prototrophy. Heterologous expression of bioWAFDBI from Bacillus subtilis encoding another biotin synthesis pathway in C. glutamicum allowed for growth in biotin-depleted media. Stable growth of the recombinant was observed without biotin addition for eight transfers to biotin-depleted medium while the empty vector control stopped growth after the first transfer. Expression of bioWAFDBI from B. subtilis in C. glutamicum strains overproducing the amino acids l-lysine and l-arginine, the diamine putrescine, and the carotenoid lycopene, respectively, enabled formation of these products under biotin-depleted conditions. Thus, biotin-prototrophic growth and production by recombinant C. glutamicum were achieved. PMID:24486440

  11. Towards green construction

    Sustainability is the key to any development works. In the operation phase, hydro power is the most sustainable form of energy. However construction activities for the same power station are usually far from being green. The popular myth is that construction activity converts green into grey. Despite this popular myth, construction of a hydro power project in Nepal has made the project area greener than earlier during the construction phase itself. Choice of construction technology, appropriate level of environmental impact assessment, monitoring of environmental parameters along side the construction progress followed by mitigation at the right time; launching community development programmes side by side, having environmental specification in contractual documents and self-reliance to fulfill environmental obligations by contractors itself are the key factors in the environmental management within the construction activities. The main conclusions in the paper is the need to change the way to think about the project constraints

  12. A 3-D Metal-Organic Framework Constructed with Manganese(ΙΙ), 4,4'-Oxybis(benzoic acid) and 2,2'-Biphenyl: Synthesis, Crystal Structure and Photoelectric Property Characterization

    Fu-Hou Lei; Kai-Sheng Diao; Yu-Qiu Ding; Long Li

    2012-01-01

    Assembly of 4,4'-oxybis(benzoic acid) (H2L) with manganese chloride in the presence of 2,2'-biphenyl (2,2'-bpy) affords a new coordination polymer [Mn3L3(2,2'-bpy)2]n (1), in which the [MnL2]n layers are extended by L bridges resulting in a three-dimensional (3-D) coordination framework. The network structure of 1 has unusual (2,6)-connectivity and represents a new type of (812·123)(8)(3) topology. These identical and complementary networks are entangled to generate a self...

  13. Acid Rain.

    Openshaw, Peter

    1987-01-01

    Provides some background information on acid deposition. Includes a historical perspective, describes some effects of acid precipitation, and discusses acid rain in the United Kingdom. Contains several experiments that deal with the effects of acid rain on water quality and soil. (TW)

  14. Construction Automation and Robotics

    Bock, Thomas

    2008-01-01

    Due to the high complexity of the construction process and the stagnating technological development a long-term preparation is necessary to adapt it to advanced construction methods. Architects, engineers and all other participants of the construction process have to be integrated in this adaptation process. The short- and long-term development of automation will take place step-by-step and will be oriented to the respective application and requirements. In the initial phase existing building...

  15. Tilt-up construction

    Crompton, Richard E.

    1992-01-01

    CIVINS Tilt-up construction is a special form of precast concrete construction. The technique is used for constructing buildings by prefabricating concrete wall sections (panels) in a horizontal position on either the building's floor slab or on a temporary casting slab. Once the wall sections have cured, they are tilted to a vertical position using a mobile crane, they are temporarily braced in their final upright position, and finally, they are tied into the building's roof and floor sys...

  16. Construction Project Organization

    Pytlíčková, Kateřina

    2014-01-01

    The bachelor‘s thesis deals with „Construction Project Organization“. The theoretical part of this thesis explains the basic concepts of project management, describes the project´s life cycle, time planning and deals with the change management at the end of the theoretical part. The practical part deals with the project management of construction and mainly with time planning done by construction work schedule. The issue is solved on a real project led by the Czech construction company, and t...

  17. HITACHI construction CAE system

    Construction and maintenance of nuclear power plants have important problems such as shortening the construction period and reducing the construction cost. Recently, the problem of insufficient construction labor has arisen, and as drastic strategic development has become a necessary counter-measure. The following four principles are included in the measures to be taken for efficient execution of the construction work within the short construction period: (1) reduction of on-site work and expansion of module block making, (2)improvement of the accuracy of the on-site work process, adjustment and expansion of the work in parallel with the construction process, (3)improvement of efficiency of the on-site work and mechanization and automation of the work, (4)improvement of the accuracy of the management of the construction. A three dimensional simulation system plant construction plan CAE, comprising five modules has been developed. A project management system was also developed to improve the accuracy and efficiency of management work in the field

  18. Five new Zn(II) and Cd(II) coordination polymers constructed by 3,5-bis-oxyacetate-benzoic acid: Syntheses, crystal structures, network topologies and luminescent properties

    Five Zn(II) and Cd(II) coordination polymers, [Zn2(BOABA)(bpp)(OH)]·0.5H2O (1), [Cd3(BOABA)2(bpp)2(H2O)6]·2H2O (2), [Cd3(BOABA)2(2,2′-bipy)3(H2O)4]·5.5H2O (3), [CdNa(BOABA)(H2O)]2·H2O (4) and [Cd2(BOABA)(bimb)Cl(H2O)2]·H2O (5) (H3BOABA=3,5-bis-oxyacetate-benzoic acid, bpp=1,3-bi(4-pyridyl)propane, 2,2′-bipy=2,2′-bipyridine, bimb=1,4-bis(imidazol-1′-yl)butane), have been solvothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra and TG analyses. 1 is an uninodal 4-connected 2D square grid network based on binuclear zinc clusters. 2 is 2D wavelike layer structure and further linked by hydrogen bonds into the final 3D (5,6,6)-connected topology network. 3 is 3-connected 2D topology network and the 2,2′-bipy ligands decorate in two different types. 4 is a (4,8)-connected 2D topology network with heterocaryotic {Cd2Na2} clusters and BOABA3– ligands. 5 can be rationalized as a (3,10)-connected 3D topology network with tetranuclear {Cd4Cl2} clusters and BOABA3– ligands. Meanwhile, photoluminescence studies revealed that these five coordination polymers display strong fluorescent emission bands in the solid state at room temperature. - Graphical abstract: Five new d10 metal(II) coordination polymers based on H3BOABA ligand were obtained and characterized. They display different topological structures and luminescent properties. Highlights: ► Five d10 metal(II) polymers based on 3,5-bis-oxyacetate-benzoic acid were obtained. ► The polymers were structurally characterized by single-crystal X-ray diffraction. ► Polymers 1–5 display different topological structures. ► They show strong fluorescent emission bands in the solid state.

  19. Rural Infrastructure Construction in New Socialist Countryside Construction

    Guo, Hong-sheng; Guo, Yue-jun

    2012-01-01

    In the background of new socialist countryside construction, rural infrastructure construction is favorable to consolidating fundamental position of agriculture, expanding rural job opportunities, increasing farmers’ income, and favorable to development of rural economy and the national economy. Rural infrastructure construction mainly includes construction of agricultural basic production conditions, construction of rural ecological environment, construction of agricultural service system,...

  20. Different Dimensional and Structural Variations in Coordination Compounds of Cadmium, Manganese and Nickel Constructed from the Ligand 2,2'-Bipyidine-3,3',6,6'-tetracarboxylic Acid (H4bptc)

    The reactions of hydrated CdCl2, MnCl2, and NiCl2 with 2,2'-bipyidine-3,3',6,6'-tetracarboxylic acid (H4bptc) afforded the mononuclear [CdII(H2bptc)(H2O)3]·H2O (1), linear [Cd(H2bptc)(H2O)]·3H2On (2), 3-D hetero-bimetallic [NaCd(Hbptc)(H2O)] (3), layer [Mn(H2bptc)(H2O)]n (4) and a dinuclear compound [Ni2(H2bptc)-(H2O)2]·6H2O (5). These compounds have been characterized by elemental analysis, IR, and their structures have been determined by X-ray crystallography. The thermal stabilities of 1-3 were measured by thermogravimetric analysis (TGA) and their solid state luminescence properties together with the free ligand H4bptc were investigated at room temperature

  1. Different Dimensional and Structural Variations in Coordination Compounds of Cadmium, Manganese and Nickel Constructed from the Ligand 2,2'-Bipyidine-3,3',6,6'-tetracarboxylic Acid (H{sub 4}bptc)

    Xiang, Jing; Yang, Tiantian; Fu, Lulu; Luo, Ya; Wu, Jiashou [Yangtze Univ., Jingzhou (China)

    2013-09-15

    The reactions of hydrated CdCl{sub 2}, MnCl{sub 2}, and NiCl{sub 2} with 2,2'-bipyidine-3,3',6,6'-tetracarboxylic acid (H{sub 4}bptc) afforded the mononuclear [Cd{sup II}(H{sub 2}bptc)(H{sub 2}O){sub 3}]·H{sub 2}O (1), linear [Cd(H{sub 2}bptc)(H{sub 2}O)]·3H{sub 2}O{sub n} (2), 3-D hetero-bimetallic [NaCd(Hbptc)(H{sub 2}O)] (3), layer [Mn(H{sub 2}bptc)(H{sub 2}O)]n (4) and a dinuclear compound [Ni{sub 2}(H{sub 2}bptc)-(H{sub 2}O){sub 2}]·6H{sub 2}O (5). These compounds have been characterized by elemental analysis, IR, and their structures have been determined by X-ray crystallography. The thermal stabilities of 1-3 were measured by thermogravimetric analysis (TGA) and their solid state luminescence properties together with the free ligand H{sub 4}bptc were investigated at room temperature.

  2. A 3-D Metal-Organic Framework Constructed with Manganese(ΙΙ, 4,4'-Oxybis(benzoic acid and 2,2'-Biphenyl: Synthesis, Crystal Structure and Photoelectric Property Characterization

    Fu-Hou Lei

    2012-09-01

    Full Text Available Assembly of 4,4'-oxybis(benzoic acid (H2L with manganese chloride in the presence of 2,2'-biphenyl (2,2'-bpy affords a new coordination polymer [Mn3L3(2,2'-bpy2]n (1, in which the [MnL2]n layers are extended by L bridges resulting in a three-dimensional (3-D coordination framework. The network structure of 1 has unusual (2,6-connectivity and represents a new type of (812·123(8(3 topology. These identical and complementary networks are entangled to generate a self-penetrating supramolecular lattice. Moreover, the fluorescence spectrum of 1 exhibits fluorescent emission in the solution of methanol at room temperature. Electrochemical investigation illustrates the electrochemical properties of the title compound. The structure (C62H40Mn3N4O15n is monoclinic with a = 14.2304(18, b = 17.019(2, c = 25.805(3 Å, α = γ = 90, β = 92.932(2° and space group C2/c.

  3. Safety in construction?

    Swuste, P.H.J.J.

    2013-01-01

    The available literature on Construction Safety is not very optimistic about the chances of evidence-based safety in the construction industry exerting a positive influence. Many articles indicate that the structures and processes that are designed to ensure safety in the industry are poor. Safety m

  4. Intentionality Versus Constructive Empiricism

    Buekens, F.A.I.; Muller, Archibald

    2012-01-01

    textabstractBy focussing on the intentional character of observation in science, we argue that Constructive Empiricism-B. C. van Fraassen's much debated and explored view of science-is inconsistent. We then argue there are at least two ways out of our Inconsistency Argument, one of which is more easily to square with Constructive Empiricism than the other.

  5. Nuclear reactor constructions

    A method of constructing a radiation shielding plug for use in the roof of the coolant containment vault of liquid metal cooled fast breeder reactors is described. The construction allows relative movement of that part of service cables and pipes which are carried by the fixed roof and that part which is carried by the rotatable plug. (U.K.)

  6. Financing Public Library Construction.

    Rohlf, Robert H.; Stoffel, Lester L.

    1987-01-01

    Reviews financing options available to Illinois public libraries for construction or expansion, including general obligation bonds, mortgage funds, building reserve funds, building fund levies, lease back arrangements, sale of air or ground development rights, interest on special funds, gift funds and grants, Library Service and Construction Act…

  7. Personal Usability Constructs

    Hertzum, Morten; Clemmensen, Torkil; Hornbæk, Kasper;

    2011-01-01

    Whereas the concept of usability is predominantly defined analytically, people relate to systems through personal usability constructs. Based on 48 repertory-grid interviews, this study investigates how such personal constructs are affected by two factors crucial to the international development...

  8. Curriculum Guide Construction Cluster.

    Kline, Ken

    As part of a model construction cluster curriculum development project, this guide was developed and implemented in the Beaverton (Oregon) School District. The curriculum guide contains 16 units covering the following topics: introduction to construction jobs; safety and first aid; blueprint readings; basic mathematics; site work; framing; roofing…

  9. Operations management for construction

    March, Chris

    2009-01-01

    Students studying construction management and related subjects need to have a broad understanding of the major aspects of controlling the building processes. Operations Management for Construction is one of three textbooks (Business Organisation, Operations Management and Finance Control) written to systematically cover the field. Focusing on construction sites and operations which are challenging to run, Chris March explores issues such as the setting up of the site, the deciding of the methodology of construction, and the sequence of work and resourcing. As changing and increasing regulations affect the way sites are managed, he also considers the issues and methods of successful administering, safety, quality and environment. Finally, the contractor's responsibility to the environment, including relationships with third parties, selection of materials, waste management and sustainability is discussed. Chris March has a wealth of practical experience in the construction industry, as well as considerable exp...

  10. VENTILATION NEEDS DURING CONSTRUCTION

    The purpose of this analysis is to determine ventilation needs during construction and development of the subsurface repository and develop systems to satisfy those needs. For this analysis, construction is defined as pre-emplacement excavation and development is excavation that takes place simultaneously with emplacement. The three options presented in the ''Overall Development and Emplacement Ventilation Systems'' analysis (Reference 5.5) for development ventilation will be applied to construction ventilation in this analysis as well as adding new and updated ventilation factors to each option for both construction and development. The objective of this analysis is to develop a preferred ventilation system to support License Application Design. The scope of this analysis includes: (1) Description of ventilation conditions; (2) Ventilation factors (fire hazards, dust control, construction logistics, and monitoring and control systems); (3) Local ventilation alternatives; (4) Global ventilation options; and (5) Evaluation of options

  11. VENTILATION NEEDS DURING CONSTRUCTION

    C.R. Gorrell

    1998-07-23

    The purpose of this analysis is to determine ventilation needs during construction and development of the subsurface repository and develop systems to satisfy those needs. For this analysis, construction is defined as pre-emplacement excavation and development is excavation that takes place simultaneously with emplacement. The three options presented in the ''Overall Development and Emplacement Ventilation Systems'' analysis (Reference 5.5) for development ventilation will be applied to construction ventilation in this analysis as well as adding new and updated ventilation factors to each option for both construction and development. The objective of this analysis is to develop a preferred ventilation system to support License Application Design. The scope of this analysis includes: (1) Description of ventilation conditions; (2) Ventilation factors (fire hazards, dust control, construction logistics, and monitoring and control systems); (3) Local ventilation alternatives; (4) Global ventilation options; and (5) Evaluation of options.

  12. Motivating Workers in Construction

    Jason E. Barg

    2014-01-01

    Full Text Available The study of the motivation of construction workers is limited to a relatively small body of knowledge. Although there is considerable research available regarding motivation and productivity, few researchers have provided a comprehensive analysis on the motivation of construction workers. The research stated that productivity in construction has not improved compared to other industry sectors such as manufacturing. This trend has been echoed in publications throughout the past five decades, and suggested that motivation is one of the key factors impacting productivity. This paper offers a comprehensive review of the published work that directly links the key words—construction and motivation. The findings have been presented in five themes, that is, motivation models, environment and culture, incentives and empowerment, and worker management. This paper concludes with two methods suggested by previous researchers to improve motivation of construction workers: (1 relevant worker incentives (intrinsic or extrinsic and (2 improved management practices, specifically regarding communication with workers.

  13. Utilization of mixed ligands to construct diverse Ni(II)-coordination polymers based on terphenyl-2,2‧,4,4‧-tetracarboxylic acid and varied N-donor co-ligands

    Wang, Chao; Zhao, Jun; Xia, Liang; Wu, Xue-Qian; Wang, Jian-Fang; Dong, Wen-Wen; Wu, Ya-Pan

    2016-06-01

    Three new coordination polymers, namely, {[Ni(H2L)(bix)(H2O)2]·2h2O}n (1), {[Ni(HL)(Hdpa)(H2O)2]·H2O}n (2), {[Ni(L)0.5(bpp)(H2O)]·H2O}n (3) (H4L=terphenyl-2,2‧,4,4‧-tetracarboxylic acid; bix=1,4-bis(imidazol-1-ylmethyl)benzene; dpa =4,4‧-dipyridylamine; bpp=1,3-bis(4-pyridyl)propane), based on rigid H4L ligand and different N-donor co-ligands, have been synthesized under hydrothermal conditions. Compound 1 features a 3D 4-connected 66-dia-type framework with H4L ligand adopts a μ2-bridging mode with two symmetry-related carboxylate groups in μ1-η1:η0 monodentate mode. Compound 2 displays a 1D [Ni(HL)(Hdpa)]n ribbon chains motif, in which the H4L ligand adopts a μ2-bridging mode with two carboxylate groups in μ1-η1:η1 and μ1-η1:η0 monodentate modes, while 3 possesses a (4,4)-connected 3D frameworks with bbf topology, with H4L ligand displays a μ4-bridging coordination mode. The H4L ligand displays not only different deprotonated forms but also diverse coordination modes and conformations. The structural diversities among 1-3 have been carefully discussed, and the roles of N-donor co-ligands in the self-assembly of coordination polymers have been well documented.

  14. Folic Acid

    ... found naturally in some foods, including leafy vegetables, citrus fruits, beans (legumes), and whole grains. Folic acid ... mcg of folic acid every day for good health. But older adults need to be sure they ...

  15. Diversity in coordination behavior of dipicolinic acid with lead(II), calcium(II), and nickel(II) in the presence of pyrazine and 2-amino-4-methylpyridine spacers in construction of three supramolecular architectures

    Eshtiagh-Hosseini, Hossein; Aghabozorg, Hossein; Mirzaei, Masoud; Amini, Mostafa M.; Chen, Ya-Guang; Shokrollahi, Ardeshir; Aghaei, Roghayyeh

    2010-06-01

    Three coordination compounds, [Pb(pydc)] n ( 1), [Ca 2(pydc) 2(H 2O) 6]·2pydcH 2 ( 2), and [ampyH] 2[Ni(H 2O) 6][Ni(pydc) 2] 2·2H 2O ( 3) (pydc = pyridine-2,6-dicarboxylate ion and ampy = 2-amino-4-methylpyridine), have been prepared by the hydrothermal method and characterized by elemental analyses, FTIR, 1H NMR spectroscopies, and single crystal X-ray diffraction. In 1 the connection of Pb(II) atom and pydc in a double-bridge and double-chelation coordination mode creates a layer structure extending in [2 0 2¯] plane, there is a π-π stacking interaction between these layers with a short face-to-face distance of 3.289 Å. Compound 2 consists of two pydcH 2 molecules and a binuclear calcium(II) complex formed by the single-bridge and double-chelation coordination of pydc ligand. Compound 3 consists of two coordination anions [Ni(pydc) 2] 2-, one coordination cation, [Ni(H 2O) 6] 2+, two protonated organic cations, ampyH +, and two water molecules. In [Ni(pydc) 2] 2-, Ni1 is coordinated by two (pydc) 2- ligands in a double-chelate mode, exhibiting an octahedral geometry. The π-π stacking interactions between pydcH 2 and the Ca complex in 2 and between pydc ligands in 3, and also the hydrogen bonds between coordination water molecules and pydcH 2/pydc are the 3D supramolecular architecture constructing force. The protonation constants of ampy, pz (pyrazine) and pydcH 2, as the building blocks of the proton transfer systems (pydcH 2-ampy and pydcH 2-pz) and their corresponding stability constants were determined by potentiometric studies. The stoichiometry and stability constants of pydc-ampy complex with Ni 2+ and pydc-pz complexes with Ca 2+ and Pb 2+ was investigated by potentiometric technique in aqueous solution. The results from solution studies were compared with the solid state data, in details.

  16. Constructing supramolecular nanostructure by hydrogen-bonding

    LI YiBao; ZENG QingDao; WANG ZhiHui; QI GuiCun; GUAN Li; FAN XiaoLin; WANG Chen

    2008-01-01

    The diquinoxalino (2.3-2'.3'-a.c) phenazine (DQP), containing 6 nitrogen atoms, was synthesized, and its adsorption and self-assembling behavior on highly oriented pyrolytic graphite (HOPG) was studied by scanning tunneling microscopy (STM) under ambient conditions. With 1,14-tetradecanedioic acid as a bridge, uniform two-dimensional arrays of 1,14-tetradecanedioic acid/DQP nanostrueture were suc-cessfully fabricated. The result illustrates that it is possible to construct and control supramolecular nanostructure by intermolecular hydrogen-bonding.

  17. Radon resistant new construction

    This paper consist of the awareness about the ill effects of radon gas and the methods adopted to detect the presence of radon gas and to remove the radon gas. It explains the installation of radon resistant structures during home construction. Radon is commonly found in the air and water, where it poses little risk. But radon that creeps into your home from the soil can be a much greater risk. Radon-resistant construction combines common building techniques and materials to seal entry points and route the gases outdoors, helping to prevent radon from entering the home. The benefits due to radon resistant construction is also explained in this paper. (author)

  18. Sustainability Base Construction Update

    Mewhinney, Michael

    2012-01-01

    Construction of the new Sustainability Base Collaborative support facility, expected to become the highest performing building in the federal government continues at NASA's Ames Research Center, Moffet Field, Calif. The new building is designed to achieve a platinum rating under the leadership in Energy and Environment Design (LEED) new construction standards for environmentally sustainable construction developed by the U. S. Green Building Council, Washington, D. C. When completed by the end of 2011, the $20.6 million building will feature near zero net energy consumption, use 90 percent less potable water than conventionally build buildings of equivalent size, and will result in reduced building maintenance costs.

  19. Construction and Demolition Waste

    Christensen, Thomas Højlund; Andersen, L.

    Construction and demolition waste (C&D waste) is the waste generated during the building, repair, remodeling or removal of constructions. The constructions can be roads, residential housing and nonresidential buildings. C&D waste has traditionally been considered without any environmental problems...... therefore should be managed accordingly. Another reason is that it has been documented that a large fraction of C&D waste (about 90 %) can be easily recycled and thus can conserve landfill capacity. C&D waste may conveniently be divided into three subcategories: Buildings, roads and excavations. This...

  20. Construction program management

    Delaney, Joseph

    2013-01-01

    Although construction is one of the largest industries in the United States, it lags behind other industries in its implementation of modern management techniques such as those contained in the Standard for Program Management (the Standard) by the Project Management Institute (PMI(R)). Construction Program Management details the successful use of the PMI(R) approach for the construction of capital programs. It demonstrates, through case studies, how implementation of PMI's set of tools and techniques can improve the chances of program success. Exploring tactical and strategic management method

  1. Construction Experience Program (CONEX)

    A summary of the activities of the NEA WGRNR is introduced. In particular the following tasks related to the ConEx (Construction Experience Program) are presented: Rationale and goals of the ConEx program, Development of the event construction database ConEx and its structure, ConEx procedure for program management (uses of ConEx to create knowledge, conclusions of the ConEx synthesis first report on lessons learned during construction, Potential ConEx program uses for operating experience, training, etc.)

  2. Utilization of acid tars

    Frolov, A.F.; Denisova, T.L.; Aminov, A.N.

    1987-01-01

    Freshly produced acid tar (FPAT), obtained as refinery waste in treating petroleum oils with sulfuric acid and oleum, contains 80% or more sulfuric acid. Of such tars, pond acid tars, which contain up to 80% neutral petroleum products and sulfonated resins, are more stable, and have found applications in the production of binders for paving materials. In this article the authors are presenting results obtained in a study of the composition and reactivity of FPAT and its stability in storage in blends with asphalts obtained in deasphalting operations, and the possibility of using the FPAT in road construction has been examined. In this work, wastes were used which were obtained in treating the oils T-750, KhF-12, I-8A, and MS-14. Data on the change in group chemical composition of FPAT are shown, and the acidity, viscosity, needle penetration, and softening point of acid tars obtained from different grades of oils are plotted as functions of the storage time. It is also shown that the fresh and hardened FPATs differ in their solubilities in various solvents.

  3. Quantitative constructional attributes selection in construction series of types

    P. Gendarz; M. Cielniak

    2011-01-01

    Purpose: The main aim of research was to analyze the selection process of quantitative constructional attributes in construction series of types.Design/methodology/approach: The quantitative constructional attributes selection process is based on constructional similarity theory.Findings: The constructional similarity theory allows to select the quantitative constructional attributes.Research limitations/implications: The final construction similarity is not complete because of adjusting the ...

  4. Construction Minerals Operations

    Department of Homeland Security — This map layer includes construction minerals operations in the United States. The data represent commodities covered by the Minerals Information Team (MIT) of the...

  5. Nuclear power plant construction

    The legal aspects of nuclear power plant construction in Brazil, derived from governamental political guidelines, are presented. Their evolution, as a consequence of tecnology development is related. (A.L.S.L.)

  6. Pluto's Putative Cryovolcanic Constructs

    Singer, K. N.; White, O. L.; Schenk, P. M.; Moore, J. M.; Spencer, J. R.; McKinnon, W. B.; Howard, A. D.; Stern, A. S.; Cook, J. C.; Grundy, W. M.; Cruikshank, D. P.; Beyer, R. A.; Umurhan, O.; Howett, C. J. A.; Parker, A. H.; Protopapa, S.; Lauer, T. R.; Weaver, H. A.; Young, L. A.; Olkin, C. B.; Ennico, K.

    2016-06-01

    New Horizons imaged two large mounds with deep central depressions on Pluto. Both features appear constructional, and have relatively young surfaces. This mapping is part of effort to characterize and assess the age and origin of the mounds.

  7. On Construction Grammar

    XIAO Kunxue

    2005-01-01

    Constructionist approach with its brand-new perspective has begun to demonstrate its dynamic power. This paper attempts to review the basic ideas, achievements and comparison with generative grammar of Construction Grammar and generalize some problems and future research prospects.

  8. Construction, fabrication, and installation

    This standard specifies the construction, fabrication, and installation requirements that apply to concrete containment structures of a containment system designated as class containment components, parts and appurtenances for nuclear power plants

  9. Power plant construction method

    Each building is covered at upper than the position of a ceiling crane, each of the ceiling crane always disposed for every building is moved to an optional building to treat equipments and building materials by each of the ceiling crane. A plurality of ceiling cranes are used for transporting one large and heavy weighted equipment or each ceiling crane is used also individually to transport equipments to each building, construction operations are thus conducted using a plurality of ceiling cranes in one identical building or in each of buildings in a state undergoing no influences of the outer circumstance by covering the roofs. Large sized or heavy weighted equipments can be carried in, to proceed the construction smoothly, and in addition, since the construction can be performed in a state scarcely undergoing influence of outer circumstance, the period of time required for the construction can be shortened. (N.H.)

  10. Passive solar construction handbook

    Levy, E.; Evans, D.; Gardstein, C.

    1981-08-01

    Many of the basic elements of passive solar design are reviewed. The unique design constraints presented in passive homes are introduced and many of the salient issues influencing design decisions are described briefly. Passive solar construction is described for each passive system type: direct gain, thermal storage wall, attached sunspace, thermal storage roof, and convective loop. For each system type, important design and construction issues are discussed and case studies illustrating designed and built examples of the system type are presented. Construction details are given and construction and thermal performance information is given for the materials used in collector components, storage components, and control components. Included are glazing materials, framing systems, caulking and sealants, concrete masonry, concrete, brick, shading, reflectors, and insulators. The Load Collector Ratio method for estimating passive system performance is appended, and other analysis methods are briefly summarized. (LEW)

  11. Constructions of Peripherality

    Carter, Helen Frances Lindsay

    2013-01-01

    rural area of Northern Ireland, and the manner in which peripherality is constructed by a variety of different actors in this debate. In the case discussed in the article, peripherality is constructed in different ways by different actors, yet the debate becomes somewhat polarised into the environmental......In this paper I focus on the concept of peripheralisation. In particular, I consider how peripheries can be discursively constructed in the debates surrounding planning cases, and how this might serve to legitimate particular interests. This is related to the case of a proposed golf resort in a...... values of a periphery versus the ‘need’ for economic development in such a periphery. In this paper I will analyse these constructions of peripherality and discuss the manner in which different framings of the region affects planning, and perhaps legitimates certain developments. This offers a...

  12. Predictable grammatical constructions

    Lucas, Sandra

    2015-01-01

    My aim in this paper is to provide evidence from diachronic linguistics for the view that some predictable units are entrenched in grammar and consequently in human cognition, in a way that makes them functionally and structurally equal to nonpredictable grammatical units, suggesting that these...... predictable units should be considered grammatical constructions on a par with the nonpredictable constructions. Frequency has usually been seen as the only possible argument speaking in favor of viewing some formally and semantically fully predictable units as grammatical constructions. However, this paper...... semantically and formally predictable. Despite this difference, [méllo INF], like the other future periphrases, seems to be highly entrenched in the cognition (and grammar) of Early Medieval Greek language users, and consequently a grammatical construction. The syntactic evidence speaking in favor of [méllo...

  13. Employment and winter construction

    Hansen, Ernst Jan de Place; Larsen, Jacob Norvig

    2011-01-01

    possibilities exist for reducing seasonal variation in employment? In addition to a literature review related to winter construction, European and national employment and meteorological data were studied. Finally, ministerial acts, ministerial orders or other public policy documents related to winter...

  14. Steep Cut Construction

    Kumaraswamy, Mohan

    2002-01-01

    One element of the CIVCAL project Web-based resources containing images, tables, texts and associated data on the Steep Cut Construction. This project describes construction of a petrol filling station on Pokfulam Road, Hong Kong. The project was unique in that the necessary area for the filling station was required to be cut from the base of a steeply sloping soil/rock slope adjacent to a busy highway.

  15. Constructing quantum codes

    2008-01-01

    Quantum error correcting codes are indispensable for quantum information processing and quantum computation.In 1995 and 1996,Shor and Steane gave first several examples of quantum codes from classical error correcting codes.The construction of efficient quantum codes is now an active multi-discipline research field.In this paper we review the known several constructions of quantum codes and present some examples.

  16. Construction of Permutation Snarks

    Hägglund, Jonas; Hoffmann-Ostenhof, Arthur

    2012-01-01

    A permutation snark is a snark which has a 2-factor $F_2$ consisting of two chordless circuits; $F_2$ is called the permutation 2-factor of $G$. We construct an infinite family $\\mathcal H$ of cyclically 5-edge connected permutation snarks. Moreover, we prove for every member $G \\in \\mathcal H$ that the permutation 2-factor given by the construction of $G$ is not contained in any circuit double cover of $G$.

  17. Education for sustainable construction

    Bragança, L.; Koukkari, Heli; Veljkovic, Milan; Borg, Ruben Paul

    2011-01-01

    The COST Action C25 "Sustainability of Constructions - Integrated Approach to Life-time Structural Engineering" is a network of scientists and researchers from 28 European countries and the EU Joint Research Centre in Ispra. It was established to promote science-based developments in sustainable construction in Europe through research on life-time structural engineering. The COST Action has been active since 2006.

  18. CONTRACT CONSTRUCTION ACTIVITY

    ANTOANETA CLAUDIA BUTUZA

    2010-01-01

    Full Text Available This paper presents the main types of contractual arrangements used worldwide in construction: traditional contracts, cost reimbursable type contracts, management contracts and other contractual arrangements such as partnership, offering two-phase, contracts in series and turnkey contracts. Also, based on a comparison of the main types of contractual arrangements a number of recommendations are suggested for choosing the appropriate type of contract construction project to be realized.

  19. KARATE WITH CONSTRUCTIVE LEARNING

    Srikrishna Karanam; Amarjot Singh; Devinder Kumar

    2012-01-01

    Any conventional learning process involves the traditional hierarchy of garnering of information and then recall gathered information. Constructive learning is an important research area having wide impact on teaching methods in education, learning theories, and plays a major role in many education reform movements. It is observed that constructive learning advocates the interconnection between emotions and learning. Human teachers identify the emotions of students with varying degrees of acc...

  20. Management for Construction Materials and Control of Construction Waste in Construction Industry: A Review

    A. A. Gulghane

    2015-04-01

    Full Text Available In recent treads a wide range of building materials is available for the construction of civil engineering structures. The total cost of materials may be up to 60% or more of the total cost incurred in construction project dependent upon the type of project. Effective construction materials management is a key to success for a construction project. Construction waste is another serious problem in construction industry. A large and various types of construction waste with different characteristics are created at all the stages of construction. Construction industries have a larger part in contributing environmental problems. The economic and environmental benefits must be gained from construction waste minimization. This paper presents a review on systematically investigation of the management of construction materials and construction waste, material management techniques, control of construction waste and existing situation of construction management and construction waste in the industry.

  1. AP1000 construction schedule

    Westinghouse performed this study as part of EPRI interest in advancing the use of computer aided processes to reduce the cost of nuclear power plants. EPRI believed that if one could relate appropriate portions of an advanced light water reactor plant model to activities in its construction sequence, and this relationship could be portrayed visually, then optimization of the construction sequence could be developed as never before. By seeing a 3-D representation of the plant at any point in its construction sequence, more informed decisions can be made on the feasibility or attractiveness of follow on or parallel steps in the sequence. The 3-D representation of construction as a function of time (4-D) could also increase the confidence of potential investors concerning the viability of the schedule and the plant ultimate cost. This study performed by Westinghouse confirmed that it is useful to be able to visualize a plant construction in 3-D as a function of time in order to optimize the sequence of construction activities. (author)

  2. Fat-1基因真核表达载体的构建及其对人口腔鳞癌细胞脂肪酸含量的影响%Construction of Fat-1 Eukaryotic Expression Vector and Its Effect on Fatty Acids Content of Human Oral Squamous Cell Carcinoma Cells

    李栋; 聂代邦; 王海军; 段新平; 逄大欣; 欧阳红生

    2011-01-01

    目的:构建真核表达载体 pcDNA3.1-Fat1,线性化稳定转染人口腔鳞癌细胞株Tca8113,检测其细胞内脂肪酸含量变化.方法:通过重叠延伸PCR方法人工合成利于真核表达的Fat-1基因,用基因重组技术构建真核表达载体pcDNA3.1-Fat-1,用脂质体转染真核细胞的方法转染人口腔鳞癌细胞株Tca8113,用气相色谱仪检测脂肪酸的变化情况.结果:测序及酶切鉴定成功合成真核偏好表达的Fat-1基因.与对照组相比,转染Fat-1基因的口腔癌细胞的n-3脂肪酸明显增多,n-6/n-3明显下降.结论:成功构建真核表达载体 pcDNA3.1-Fat1,并对口腔鳞癌细胞内脂肪酸含量产生明显影响,为进一步研究Fat-1基因在口腔鳞癌中的生物学功能奠定了基础.%Objective: To construct eukaryotic expression vector pcDNA3.1-Fat1 and transfect human oral squamous cell carcinoma cell line Tca8113, then tested the changes of fatty acids content in Tca8113.Methods: The Fat-1 gene was constructed by SOE-PCR.The pcDNA3.1-Fat1 was constructed by using recombinant DNA technology, human oral squamous carcinoma cells line Tca8113cells was transfected using lipofection method.The fatty acids content of the transfected Tca8113 cells was detected by using gas chromatography technology.Results: Eukaryotic expression vector pcDNA3.l-Fatl was successfully constructed and transfected into human oral squamous carcinoma cell lineTca8113.The cells that expressed the fat-1 gene had a lower n-6/n-3 PUFA ratio compared with the cells that expressed the control vector.Conclusion: The pcDNA3.1-Fat1 is successfully constructed, and it has significant effect on the PUFAs content of Tca8113 cells, which makes a foundation in the future study on the biological function of Fat-1 gene in human oral squamous carcinoma.

  3. Uso de entulho de construção civil como sistema de cobertura para abatimento de drenagem ácida de mina em uma mina abandonada de pirita Use of solid residues from civil construction as a covering system for acid mine drainage abatement in an abandoned pyrite mine

    Natália Cristiane de Moraes

    2011-06-01

    Full Text Available Em Ouro Preto/MG, pirita foi extraída em uma antiga mina, denominada Jazida de Pirita, durante os anos de 1930 a 1967. Considerada como uma das melhores jazidas de pirita no Brasil, essa mina foi explotada com o objetivo de atender à demanda por ácido sulfúrico, para fabricação de explosivos, da Fábrica Presidente Vargas em Piquete/SP. O local da mina está abandonado e tem, como principais passivos ambientais, a instabilidade das encostas e a geração de drenagem ácida. Atualmente, o local tem sido utilizado para lançamento clandestino de entulho na área o que contribui para o aumento do impacto ambiental. A Prefeitura de Ouro Preto, por sua vez, tem intenção de usar parte da área da mina para disposição de resíduo de construção civil. Esse artigo apresenta os resultados dos ensaios cinéticos realizados, em colunas de lixiviação, para avaliação do potencial de geração de drenagem ácida, em amostras coletadas da mina de pirita, e analisa a possibilidade de controle ou de minimização da drenagem ácida, utilizando-se do entulho como cobertura. Os resultados encontrados mostram que a utilização do entulho como sistema de cobertura foi eficiente na redução de acidez, na concentração de metais e sulfato presentes nas colunas analisadas.In Ouro Preto/MG, pyrite was exploited at an old mine from 1930 through 1967. Considered as one of the best resources of pyrite in Brazil, this mine was exploited in order to supply sulfuric acid for explosives manufacturing, at the President Vargas Plant in Piquete/SP. The mine site is abandoned and has slope instability and acid leakage generation as the main environmental liabilities. Lately, the site has been used for illegal deposition of all sorts of urban waste. The Ouro Preto Administration, on its turn, has the intention of using part of the mine site for the disposal of solid residues of civil construction. This paper presents the results of kinetic tests carried out, in

  4. Management for Construction Materials and Control of Construction Waste in Construction Industry: A Review

    A. A. Gulghane; Prof P. V. Khandve

    2015-01-01

    In recent treads a wide range of building materials is available for the construction of civil engineering structures. The total cost of materials may be up to 60% or more of the total cost incurred in construction project dependent upon the type of project. Effective construction materials management is a key to success for a construction project. Construction waste is another serious problem in construction industry. A large and various types of construction waste with different...

  5. Construction time of PWRs

    Carajilescov, Pedro; Moreira, Joao M.L., E-mail: pedro.carajilescov@ufabc.edu.b, E-mail: joao.moreira@ufabc.edu.b [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil). Center of Engineering, Modeling and Applied Social Sciences

    2011-07-01

    The cost of electricity generated by nuclear power is greatly affected by the capital cost, which is dependent on the construction time of the plant. This work analyses the construction time of PWRs in several countries with different market structure and licensing experience. Countries which succeeded to establish a more collaborative environment among utilities, constructors, regulators, and energy planners through effective partnerships were able to build PWRs in shorter times. The construction time in Germany, France and Russia was around 80 months and in Japan, about 60 months. The envelope of 95% of the cases includes a range between 50 and 250 months of construction time. The evaluations show that construction time of PWRs has been longer for countries that did not hold the technology to build their own reactors, and depended on contracts with foreign suppliers. The nominal power of the reactors was considered a measure of plant size, technology complexity and standardization. Countries with standardized reactor designs (France, Japan and Russia) were able to build plants in shorter times. (author)

  6. Construction time of PWRs

    The cost of electricity generated by nuclear power is greatly affected by the capital cost, which is dependent on the construction time of the plant. This work analyses the construction time of PWRs in several countries with different market structure and licensing experience. Countries which succeeded to establish a more collaborative environment among utilities, constructors, regulators, and energy planners through effective partnerships were able to build PWRs in shorter times. The construction time in Germany, France and Russia was around 80 months and in Japan, about 60 months. The envelope of 95% of the cases includes a range between 50 and 250 months of construction time. The evaluations show that construction time of PWRs has been longer for countries that did not hold the technology to build their own reactors, and depended on contracts with foreign suppliers. The nominal power of the reactors was considered a measure of plant size, technology complexity and standardization. Countries with standardized reactor designs (France, Japan and Russia) were able to build plants in shorter times. (author)

  7. Construction and Demolition Waste

    Christensen, Thomas Højlund; Andersen, L.

    2011-01-01

    Construction and demolition waste (C&D waste) is the waste generated during the building, repair, remodeling or removal of constructions. The constructions can be roads, residential housing and nonresidential buildings. C&D waste has traditionally been considered without any environmental problems...... and has just been landfilled. However, in recent years more focus has been put on C&D waste and data are starting to appear. One reason is that it has been recognized that C&D waste may include many materials that are contaminated either as part of their original design or through their use and...... therefore should be managed accordingly. Another reason is that it has been documented that a large fraction of C&D waste (about 90 %) can be easily recycled and thus can conserve landfill capacity. C&D waste may conveniently be divided into three subcategories: Buildings, roads and excavations. This...

  8. Constructing populations in biobanking

    Tupasela, Aaro; Snell, Karoliina; Cañada, Jose a.

    2015-01-01

    This article poses the question of whether biobanking practices and standards are giving rise to the construction of populations from which various biobanking initiatives increasingly draw on for legitimacy? We argue that although recent biobanking policies encourage various forms of engagement...... construction of populations, whereby specific nationalities, communities, societies, patient groups and political systems become imbued or bio-objectified with particular characteristics, such as compliant, distant, positive, commercialized or authoritarian. This bio-objectification process is problematic in...... relation to policy aspirations ascribed to biobanking engagement since it gives rise to reified notions of different populations....

  9. Logic, construction, computation

    Berger, Ulrich; Diener, Hannes; Seisenberger, Monika

    2012-01-01

    Over the last few decades the interest of logicians and mathematicians in constructive and computational aspects of their subjects has been steadily growing, and researchers from disparate areas realized that they can benefit enormously from the mutual exchange of techniques concerned with those aspects. A key figure in this exciting development is the logician and mathematician Helmut Schwichtenberg to whom this volume is dedicated on the occasion of his 70th birthday and his turning emeritus. The volume contains 20 articles from leading experts about recent developments in Constructive set t

  10. Construction Management Meets Today's Realities.

    Day, C. William

    1979-01-01

    Construction management--the control of cost and time from concept through construction--grew out of a need to meet the realities of today's economy. A checklist of services a construction manager provides is presented. (Author/MLF)

  11. Rural Infrastructure Construction in New Socialist Countryside Construction

    2012-01-01

    In the background of new socialist countryside construction,rural infrastructure construction is favorable to consolidating fundamental position of agriculture,expanding rural job opportunities,increasing farmers’ income,and favorable to development of rural economy and the national economy. Rural infrastructure construction mainly includes construction of agricultural basic production conditions,construction of rural ecological environment,construction of agricultural service system,and construction of rural living facilities. Finally,we put forward approaches and methods for strengthening rural infrastructure construction: firstly,increase fund input to provide financial support for rural infrastructure construction; second ly,make scientific village planning to ensure sustainability of rural infrastructure construction; thirdly,arouse farmers’ enthusiasm and initiative to promote stable development of rural infrastructure construction.

  12. Ibotenic acid and thioibotenic acid

    Hermit, Mette B; Greenwood, Jeremy R; Nielsen, Birgitte;

    2004-01-01

    In this study, we have determined and compared the pharmacological profiles of ibotenic acid and its isothiazole analogue thioibotenic acid at native rat ionotropic glutamate (iGlu) receptors and at recombinant rat metabotropic glutamate (mGlu) receptors expressed in mammalian cell lines....... Thioibotenic acid has a distinct pharmacological profile at group III mGlu receptors compared with the closely structurally related ibotenic acid; the former is a potent (low microm) agonist, whereas the latter is inactive. By comparing the conformational energy profiles of ibotenic and thioibotenic acid with...... the conformations preferred by the ligands upon docking to mGlu1 and models of the other mGlu subtypes, we propose that unlike other subtypes, group III mGlu receptor binding sites require a ligand conformation at an energy level which is prohibitively expensive for ibotenic acid, but not for...

  13. Increase of betulinic acid production in Saccharomyces cerevisiae by balancing fatty acids and betulinic acid forming pathways.

    Li, Jing; Zhang, Yansheng

    2014-04-01

    Betulinic acid is a plant-based triterpenoid that has been recognized for its antitumor and anti-HIV activities. The level of betulinic acid in its natural hosts is extremely low. In the present study, we constructed betulinic acid biosynthetic pathway in Saccharomyces cerevisiae by metabolic engineering. Given the betulinic acid forming pathways sharing the common substrate acetyl-CoA with fatty acid synthesis, the metabolic fluxes between the two pathways were varied by changing gene expressions, and their effects on betulinic acid production were investigated. We constructed nine S. cerevisiae strains representing nine combinations of the flux distributions between betulinic acid and fatty acid pathways. Our results demonstrated that it was possible to improve the betulinic acid production in S. cerevisiae while keeping a desirable growth phenotype by optimally balancing the carbon fluxes of the two pathways. Through modulating the expressions of the key genes on betulinic acid and fatty acid pathways, the difference in betulinic acid yield varied largely in the range of 0.01-1.92 mg L(-1) OD(-1). The metabolic engineering approach used in this study could be extended for synthesizing other triterpenoids in S. cerevisiae. PMID:24389702

  14. Federal Environmental Requirements for Construction

    Department of Veterans Affairs — This guide provides information on federal environmental requirements for construction projects. It is written primarily for owners of construction projects and for...

  15. Structural safety during construction

    Terwel, K.C.; Mud, M.; Frijters, A.

    2014-01-01

    Structural safety during construction is a main concern for the building industry. Collapses of temporary structures or incomplete permanent structures are a threat for the safety of persons. Based on data from Dutch Labour Inspectorate this study concluded that approximately 20% of the fatalities d

  16. Neuroeconomics: Constructing identity

    J.B. Davis

    2010-01-01

    The paper asks whether neuroeconomics will make instrumental use of neuroscience to adjudicate existing disputes in economics or be more seriously transformed by neuroscience in ways that might transform economics. The paper pursues the question by asking how neuroscience constructs an understanding

  17. Nanotechnologies for sustainable construction

    Geiker, Mette Rica; Andersen, Maj Munch

    2009-01-01

    This chapter aims to highlight key aspects and recent trends in the development and application of nanotechnology to facilitate sustainable construction, use and demolition of buildings and infrastructure structures, ‘nanoconstruction’. Nanotechnology is not a technology but a very diverse...

  18. Construct for excellence II

    McInnis, A

    2001-01-01

    Professor Arthur McInnis continues his review of the Report of the Construction Industry Review Committee ('CIRC'). This month he looks at its recommendations on risk management, quality, value management, sub-contractor registration, structured site supervision and independent audits — as well as a proposed new institutional framework.

  19. Skin Problems in Construction

    ... 1926.95 www.osha.gov Check the Label & Safety Data Sheet: OSHA’s Hazard Communication Standard – 29 CFR 1926.59 www.osha.gov/dsg/hazcom/index.html Physician’s Alert: Occupational Contact Dermatitis Among Construction Workers – give this Alert ...

  20. Construction of Resilient Functions

    ZHANG Jie; WEN Qiao-yan

    2005-01-01

    Based on the relationship between nonlinearity and resiliency of a multi-output function, we present a method for constructing nonintersecting linear codes from packing design. Through these linear codes, we obtain n-variable, moutput, t-resilient functions with very high nonlinearity.Their nonlinearities are currently the best results for most of cases.

  1. Constructions in Wonderland

    Jensen, Kim Ebensgaard; Shibuya, Yoshikata

    -gram analysis to some different texts, including Lewis Carroll's 1865 novel Alice's Adventures in Wonderland (AW), Mark Twain's 1884/5 novel The Adventures of Huckleberry Finn (HF), and some US presidential speeches, to identify frequently (co)occurring words that may be indicative of underlying constructions...

  2. Interlanguage Passive Construction

    Simargool, Nirada

    2008-01-01

    Because the appearance of the passive construction varies cross linguistically, differences exist in the interlanguage (IL) passives attempted by learners of English. One such difference is the widely studied IL pseudo passive, as in "*new cars must keep inside" produced by Chinese speakers. The belief that this is a reflection of L1 language…

  3. On the Kummer construction

    Andreatta, Marco; Wisniewski, Jaroslaw A.

    2008-01-01

    We discuss a generalization of Kummer construction which, on the base of an integral representation of a finite group and local resolution of its quotient, produces a higher dimensional variety with trivial canonical class. As an application we compute cohomology of some generalized Kummer varieties.

  4. Mortality table construction

    Sutawanir

    2015-12-01

    Mortality tables play important role in actuarial studies such as life annuities, premium determination, premium reserve, valuation pension plan, pension funding. Some known mortality tables are CSO mortality table, Indonesian Mortality Table, Bowers mortality table, Japan Mortality table. For actuary applications some tables are constructed with different environment such as single decrement, double decrement, and multiple decrement. There exist two approaches in mortality table construction : mathematics approach and statistical approach. Distribution model and estimation theory are the statistical concepts that are used in mortality table construction. This article aims to discuss the statistical approach in mortality table construction. The distributional assumptions are uniform death distribution (UDD) and constant force (exponential). Moment estimation and maximum likelihood are used to estimate the mortality parameter. Moment estimation methods are easier to manipulate compared to maximum likelihood estimation (mle). However, the complete mortality data are not used in moment estimation method. Maximum likelihood exploited all available information in mortality estimation. Some mle equations are complicated and solved using numerical methods. The article focus on single decrement estimation using moment and maximum likelihood estimation. Some extension to double decrement will introduced. Simple dataset will be used to illustrated the mortality estimation, and mortality table.

  5. Principles of constructional change

    Fried, Mirjam

    Oxford : Oxford University Press, 2013 - (Hoffmann, T.; Trousdale, G.), s. 419-437 ISBN 978-0-19-539668-3 R&D Projects: GA ČR GAP406/11/2021 Keywords : grammaticalization * gradualness of change * constructionalization * constructional map Subject RIV: AI - Linguistics

  6. Constructing Regional advantage

    Asheim, Bjørn T.; Boschma, Ron; Cooke, Phil

    2011-01-01

    This paper presents a regional innovation policy model based on the idea of constructing regional advantage. This policy model brings together concepts like related variety, knowledge bases and policy platforms. Related variety attaches importance to knowledge spillovers across complementary...... economic development within and between regions in action lines appropriate to incorporate the basic principles behind related variety and differentiated knowledge bases....

  7. Handley Page metal construction

    1929-01-01

    In this report Handley Page construction techniques are shown such as: solid-drawn tubular duralumin spars are used in the stabilizer; plain channel sections are used extensively for minor components; and the manner of assembling them into a stabilizer compression strut is shown.

  8. Constructive Approach Towards Protocells

    Sugawara, Tadashi; Kurihara, Kensuke; Suzuki, Kentaro

    2013-12-01

    In this chapter, we describe the construction of a self-reproducing giant vesicle (GV) and the replication of an informational substance (DNA) in the GV. The linkage between these two amplification dynamics has led to generation of a model protocell.

  9. Construction Mechanic 1 & C.

    Seitz, Thomas E.

    This Rate Training Manual and Nonresident Career Course (RTM/NRCC) form a self-study package that will enable Naval Construction Mechanics First and Chief to fulfill the requirements of their rating. (Persons holding these ratings direct and coordinate efforts of individuals and crews in maintaining, repairing, and overhauling automotive,…

  10. Construction Management: Planning Ahead.

    Arsht, Steven

    2003-01-01

    Explains that preconstruction planning is essential when undertaking the challenges of a school building renovation or expansion, focusing on developing a detailed estimate, creating an effective construction strategy, conducting reviews and value-engineering workshops, and realizing savings through effective risk analysis and contingency…

  11. ACCELERATING CONSTRUCTION INDUSTRY DEVELOPMENT

    Mohan M. Kumaraswamy

    2006-06-01

    Full Text Available The needs for construction industry development are initially viewed from the broader perspectives of imperatives for infrastructure development and national development. All these are clearly more critical in developing countries. A non-exhaustive set of potential drivers and common barriers to construction industry development is identified from previous research. These suggest the usefulness of consolidating a cluster of recent proposals and exercises aiming at (a construction organization development in terms of an over-arching management support system model, as well as improved information and knowledge management; and (b project team development in the context of relationally integrated teams and supply chains, joint risk management and ‘technology and knowledge exchange’ in joint ventures, as well as longer term public private partnerships. These apparently disparate research thrusts are threaded together into a pattern that may inspire, if not feed, specific research and development (R & D agendas for construction industry development in different countries according to their own priorities, constraints and stages of infrastructure and national development.

  12. Mirror Symmetry Constructions

    Clader, Emily

    2014-01-01

    These expository notes are based on lectures by Yongbin Ruan during a special semester on the B-model at the University of Michigan in Winter 2014. They outline and compare the mirror symmetry constructions of Batyrev-Borisov, Hori-Vafa, and Bergland-Hubsch-Krawitz.

  13. Energy-Friendly Construction

    2006-01-01

    A building is a base for human activities, but it also consumes a large amount of energy and resources. Of all the newly constructed buildings throughout China, it is estimated only 10 to 15 percent are up to the state standard, and over 80 percent require enormous energy consumption. This

  14. KARATE WITH CONSTRUCTIVE LEARNING

    Srikrishna Karanam

    2012-02-01

    Full Text Available Any conventional learning process involves the traditional hierarchy of garnering of information and then recall gathered information. Constructive learning is an important research area having wide impact on teaching methods in education, learning theories, and plays a major role in many education reform movements. It is observed that constructive learning advocates the interconnection between emotions and learning. Human teachers identify the emotions of students with varying degrees of accuracy and can improve the learning rate of the students by motivating them. In learning with computers, computers also should be given the capability to recognize emotions so as to optimize the learning process. Image Processing is a very popular tool used in the process of establishing the theory of Constructive Learning. In this paper we use the Optical Flow computation in image sequences to analyze the accuracy of the moves of a karate player. We have used the Lucas-Kanade method for computing the optical flow in image sequences. A database consisting of optical flow images by a group of persons learning karate is formed and the learning rates are analyzed in order to main constructive learning. The contours of flow images are compared with the standard images and the error graphs are plotted. Analysis of the emotion of the amateur karate player is made by observing the error plots.

  15. [Gastric Acid].

    Ruíz Chávez, R

    1996-01-01

    Gastric acid, a product of parietal cells secretion, full fills multiple biological roles which are absolutely necessary to keep corporal homeostasis. The production of the acid depends upon an effector cellular process represented in the first step by histamine, acetilcholine and gastrin, first messengers of the process. These interact with specific receptors than in sequence activate second messengers -cAMP and the calcium-calmodulin system- which afterwards activate a kinase. An specific protein is then phosphorilated by this enzyme, being the crucial factor that starts the production of acid. Finally, a proton bomb, extrudes the acid towards the gastric lumen. The secretion process mentioned above, is progressive lyactivated in three steps, two of which are stimulators -cephalic and gastric phases- and the other one inhibitor or intestinal phase. These stages are started by mental and neurological phenomena -thought, sight, smell or memory-; by food, drugs or other ingested substances; and by products of digestion. Changes in regulation of acid secretion, in the structure of gastro-duodenal mucosal barrier by a wide spectrum of factors and agents including food, drugs and H. pylori, are the basis of acid-peptic disease, entity in which gastric acid plays a fundamental role. From the therapeutic point of view, so at the theoretical as at the practical levels, t is possible to interfere with the secretion of acid by neutralization of some of the steps of the effector cellular process. An adequate knowledge of the basics related to gastric acid, allows to create strategies for the clinical handling of associated pathology, specifically in relation to peptic acid disease in all of the known clinical forms. PMID:12165790

  16. Quantitative constructional attributes selection in construction series of types

    P. Gendarz

    2011-11-01

    Full Text Available Purpose: The main aim of research was to analyze the selection process of quantitative constructional attributes in construction series of types.Design/methodology/approach: The quantitative constructional attributes selection process is based on constructional similarity theory.Findings: The constructional similarity theory allows to select the quantitative constructional attributes.Research limitations/implications: The final construction similarity is not complete because of adjusting the dimension values to preferred numbers, catalogue and standardized elements dimensions etc.Practical implications: Presented method was applied to generate the constructions series of types with the use of quantitative constructional attributes selection process.Originality/value: Described analysis presents the process of selecting the quantitative constructional attributes with computer aid.

  17. Total Synthesis of (±)-Mitorubrinic Acid

    Marsini, Maurice A.; Gowin, Kristoffer M.; Pettus, Thomas R. R.

    2006-01-01

    (±)-Mitorubrinic acid, a member of the azaphilone family of natural products, has been constructed in 12 steps. Key aspects of the synthesis include elaboration and oxidative dearomatization of an isocoumarin intermediate to provide the azaphilone nucleus with a disubstituted, unsaturated carboxylic acid side chain.

  18. The Specifications for Monitoring of Acid Rain

    Tang Jie

    2011-01-01

    Background Since China is a country seriously affected by acid rain pollution,it is a long-term fundamental work for acid rain pollution prevention and control in China by getting well informed of the characteristics of spatial and temporal changes in acid rain and long-term trends of these changes.In order to reach the national demand for acid rain monitoring data,the China Meteorological Administration (CMA) began to construct the network of acid rain monitoring stations in 1992.By the end of 2010,the total number of monitoring stations has exceeded 340.

  19. Constructing futures : industry leaders and future thinking in construction.

    Chan, Paul; Cooper, Rachel

    2010-01-01

    There is growing interest in future scenario planning of the construction industry but a disconnect between thinking about the future at the policy-making level and implementing real change. Constructing Futures: industry leaders and futures thinking in construction takes a thematic approach to the future of the UK construction industry by presenting the results of a series of in-depth interviews conducted with leading construction figures and structuring this material into chapters addressin...

  20. Recycling construction waste and re – use in road construction

    Kumlanc, Peter

    2005-01-01

    Construction activities have a huge harmful influence on environment, caused by the explotation of natural resourcess, production and transportation of materials, construction and demolition and finally the building itself. To minimize construction activities on environment, we need to reduce usage of primary sources and attend to prepare secundary sources. The present work describes recycling construction and demolition waste and re-using in building roads and other construction. In Diploma ...

  1. Foreign construction workers in Singapore.

    Ofori G

    1997-01-01

    Provides an overview of the construction industry in Singapore. Studies the structure of the construction workforce, the terms of employment, policies towards worker, the effects of employment of foreign workers on local industry, the reducing reliance on foreign construction workers, and the future trends in Singapore's requirements for construction workers.

  2. Constructing the Audience

    Willig, Ida

    2010-01-01

    No more than twenty years ago, the doors between the newsrooms and the marketing departments of Danish newspapers were tightly shut. Today, all major Danish newspapers work with reader profiles using marketing data to create journalistic concepts. This article identifies two dominant reader...... constructions in policy papers of Danish newspapers: the reader-as-citizen, which can be traced back to the late 1940s, and the reader-as-consumer, visible in the historically new reader profiles, where we also find a third reader construction, the reader-as-commodity. The development indicates a transformation...... from an Omnibus press system with a publicist logic of practice to a Segment press system with a commercial logic of practice....

  3. Construction with macromolecules

    Stefan Hecht

    2005-03-01

    Full Text Available The generation of nanosized features via the bottom-up organization of individual atoms and molecules represents one of the most rapidly emerging fields in modern science and technology. In order to gain general and modular access to nanostructures, a construction kit consisting of molecular building blocks with defined nanoscale dimensions, shape, and functionality is required. While nature has developed a hierarchical strategy to construct sophisticated and complex nanostructures, chemistry is just starting to explore artificial macromolecules as a means to synthesize specific nano-objects. In this review, recent advances in achieving control over conformation within macromolecules and the interconnection of conformationally defined subunits by either covalent bonds or self-assembly are discussed in analogy to natural structure evolution.

  4. Construction quality assurance report

    Roscha, V.

    1994-09-08

    This report provides a summary of the construction quality assurance (CQA) observation and test results, including: The results of the geosynthetic and soil materials conformance testing. The observation and testing results associates with the installation of the soil liners. The observation and testing results associated with the installation of the HDPE geomembrane liner systems. The observation and testing results associated with the installation of the leachate collection and removal systems. The observation and testing results associated with the installation of the working surfaces. The observation and testing results associated with in-plant manufacturing process. Summary of submittal reviews by Golder Construction Services, Inc. The submittal and certification of the piping material specifications. The observation and verification associated of the Acceptance Test Procedure results of the operational equipment functions. Summary of the ECNs which are incorporated into the project.

  5. Constructing populations in biobanking.

    Tupasela, Aaro; Snell, Karoliina; Cañada, Jose A

    2015-01-01

    This article poses the question of whether biobanking practices and standards are giving rise to the construction of populations from which various biobanking initiatives increasingly draw on for legitimacy? We argue that although recent biobanking policies encourage various forms of engagement with publics to ensure legitimacy, different biobanks conceptualize their engagement strategies very differently. We suggest that biobanks undertake a broad range of different strategies with regard to engagement. We argue that these different approaches to engagement strategies are contributing to the construction of populations, whereby specific nationalities, communities, societies, patient groups and political systems become imbued or bio-objectified with particular characteristics, such as compliant, distant, positive, commercialized or authoritarian. This bio-objectification process is problematic in relation to policy aspirations ascribed to biobanking engagement since it gives rise to reified notions of different populations. PMID:26194269

  6. Constructing Time Machines

    Shore, Graham M

    2003-01-01

    The existence of time machines, understood as spacetime constructions exhibiting physically realised closed timelike curves (CTCs), would raise fundamental problems with causality and challenge our current understanding of classical and quantum theories of gravity. In this paper, we investigate three proposals for time machines which share some common features: cosmic strings in relative motion, where the conical spacetime appears to allow CTCs; colliding gravitational shock waves, which in Aichelburg-Sexl coordinates imply discontinuous geodesics; and the superluminal propagation of light in gravitational radiation metrics in a modified electrodynamics featuring violations of the strong equivalence principle. While we show that ultimately none of these constructions creates a working time machine, their study illustrates the subtle levels at which causal self-consistency imposes itself, and we consider what intuition can be drawn from these examples for future theories.

  7. Construction quality assurance report

    This report provides a summary of the construction quality assurance (CQA) observation and test results, including: The results of the geosynthetic and soil materials conformance testing. The observation and testing results associates with the installation of the soil liners. The observation and testing results associated with the installation of the HDPE geomembrane liner systems. The observation and testing results associated with the installation of the leachate collection and removal systems. The observation and testing results associated with the installation of the working surfaces. The observation and testing results associated with in-plant manufacturing process. Summary of submittal reviews by Golder Construction Services, Inc. The submittal and certification of the piping material specifications. The observation and verification associated of the Acceptance Test Procedure results of the operational equipment functions. Summary of the ECNs which are incorporated into the project

  8. Constructing computer virus phylogenies

    Goldberg, L.A. [Warwick Univ., Coventry (United Kingdom) Dept. of Computer Science; Goldberg, P.W. [Aston Univ., Birmingham (United Kingdom) Dept. of Applied Mathematics; Phillips, C.A. [Sandia National Labs., Albuquerque, NM (United States); Sorkin, G.B. [International Business Machines Corp., Yorktown Heights, NY (United States). Thomas J. Watson Research Center

    1996-03-01

    There has been much recent algorithmic work on the problem of reconstructing the evolutionary history of biological species. Computer virus specialists are interested in finding the evolutionary history of computer viruses--a virus is often written using code fragments from one or more other viruses, which are its immediate ancestors. A phylogeny for a collection of computer viruses is a directed acyclic graph whose nodes are the viruses and whose edges map ancestors to descendants and satisfy the property that each code fragment is ``invented`` only once. To provide a simple explanation for the data, we consider the problem of constructing such a phylogeny with a minimal number of edges. In general, this optimization problem cannot be solved in quasi-polynomial time unless NQP=QP; we present positive and negative results for associated approximated problems. When tree solutions exist, they can be constructed and randomly sampled in polynomial time.

  9. Construction of thyroid simulators

    Full text: This work exposes the methodology of construction of thyroid simulators; which was developed considering the mathematical model for the man of reference proposed by Cristy M. The physical models are designed for different ages and is conformed by two concentric cylinders of polyvynil chloride and its anatomic form was molded with silicone (polyimethyl siloxano). The cavities that represent the lobes of the thyroid contain a radioactive solution. It was made a theoretical calculation of the damping factors for this structure reproducing the values reported in literature with a rank of acceptable uncertainty within the margin of energies of photons emitted by the radionuclides ones but using. Here a protocol of construction of these simulators appears to be used like patterns in dosimetry in alive. (orig.)

  10. Identification of the enzymatic basis for δ-aminolevulinic acid auxotrophy in a hemA mutant of escherichia coli

    The hemA mutation of Escherichia coli K-12 confers a requirement for δ-aminolevulinic acid (ALA). Cell extract prepared from the hemA strain SASX41B was incapable of producing ALA from either glutamate or glutamyl-tRNA, whereas extract of the hem+ strain HB101 formed colorimetrically detectable amounts of ALA and transferred label from 1-[14C]glutamate and 3,4-[3H]glutamyl-tRNA to ALA. Extracts of both strains converted glutamate-1-semialdehyde to ALA and were capable of aminoacylating tRNAGlu. Glutamyl-tRNA formed by extracts of both strains could be converted to ALA by the extract of hem+ cells. The extract of hemA cells did not convert glutamyl-tRNA formed by either strain to ALA. However, the hemA cell extract, when supplemented in vitro with glutamyl-tRNA dehydrogenase isolated from Chlorella vulgaris cells, formed about as much ALA as did the unsupplemented hem+ cell extract. We conclude from these observations that the enzyme activity that is lacking in the ALA auxotrophic strain carrying the hemA mutation is that of glutamyl-tRNA dehydrogenase