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Sample records for dato stenocereus griseus

  1. Efficient production of nonactin by Streptomyces griseus subsp. griseus.

    PubMed

    Zhan, Yulian; Zheng, Shaolun

    2016-08-01

    Here we report the production of the cyclic macrotetrolide nonactin from the fermentation culture of Streptomyces griseus subsp. griseus. Nonactin is a member of a family of naturally occurring cyclic ionophores known as the macrotetrolide antibiotics. Our fermentation procedure of Streptomyces griseus was performed at 30 °C and 200 rev·min(-1) for 5 days on a rotary shaker. Diaion HP-20 and Amberlite XAD-16 were added to the fermentation medium. Isolated yield of nonactin was up to 80 mg·L(-1) using our methodology. Nonactin is commonly known as an ammonium ionophore and also exhibits antibacterial, antiviral, and antitumor activities. It is also widely used for the preparation of ion-selective electrodes and sensors. Chemical synthesis of nonactin has been achieved by some groups; however, overall yields are very low, making efficient biosynthesis an attractive means of production. PMID:27405846

  2. Genetic recombination in Streptomyces griseus.

    PubMed Central

    Parag, Y

    1978-01-01

    Low-frequency (10(-6)) genetic recombination was observed in a cephamycin-producing strain of Streptomyces griseus. The recombinants were predominantly heteroclones. Heteroclone analysis was performed involving four heteroclones of one cross. In 100 mutants correlation was found between the type of auxotrophy and the level of antibiotic activity. A cross of this strain with a streptomycin-producing strain of S. griesus is described. PMID:415037

  3. Novel Biotransformations of 7-Ethoxycoumarin by Streptomyces griseus

    PubMed Central

    Sariaslani, F. Sima; Rosazza, John P.

    1983-01-01

    Biotransformation of 7-ethoxycoumarin by Streptomyces griseus resulted in the accumulation of two metabolites which were isolated and identified as 7-hydroxycoumarin and 7-hydroxy-6-methoxycoumarin. A novel series of biotransformation reactions is implicated in the conversion of the ethoxycoumarin substrate to these products, including O-deethylation, 6-hydroxylation to form a 6,7-dihydroxycoumarin catechol, and subsequent O-methylation. Either 7-hydroxycoumarin or 6,7-dihydroxycoumarin was biotransformed to 7-hydroxy-6-methoxycoumarin by S. griseus. Trace amounts of the isomeric 6-hydroxy-7-methoxycoumarin were detected when 6,7-dihydroxycoumarin was used as the substrate. Efforts to obtain a cell-free catechol-O-methyltransferase enzyme system from S. griseus were unsuccessful. However, [methyl-14C]methionine was used with cultures of S. griseus to form 7-hydroxy-6-[14C]methoxycoumarin. PMID:16346369

  4. Primary structure of Streptomyces griseus metalloendopeptidase II.

    PubMed

    Kojima, S; Kumazaki, T; Ishii, S; Miura, K

    1998-07-01

    Streptomyces griseus metalloendopeptidase II (SGMPII) is a unique protease, since it shows anomalous susceptibility to the proteinaceous "serine protease inhibitors" produced by Streptomyces, such as Streptomyces subtilisin inhibitor (SSI) and its homologous proteins. In this study, we analyzed the amino acid sequence of SGMPII by analyzing various peptide fragments produced enzymatically. The sequence of SGMPII, which is composed of 334 amino acids, showed no extensive similarity to SSI-insensitive metalloproteases produced by other species of Streptomyces, except for the amino acid residues essential for catalysis and zinc binding. However, SGMPII is 35-41% similar to thermolysin and its related metalloproteases, which are not inhibited by SSI, and the residues presumed to be critical for catalysis and zinc-binding are well conserved in SGMPII. Glu137 in a "His-Glu-Xaa-His" motif of SGMPII was identified as the residue modified by CICH2 CO-DL-(N-OH)Leu-Ala-Gly-NH2, an active-site-directed irreversible inhibitor of thermolysin-like metalloproteases. Based on the sequence comparison of SGMPII and other bacterial metalloproteases, we discuss the structural basis for the differences in substrate specificity and stability between SGMPII and other thermolysin-like proteases. A possible SSI-binding locus of SGMPII is also proposed. PMID:9720222

  5. Echolocation in the Risso's dolphin, Grampus griseus

    NASA Astrophysics Data System (ADS)

    Philips, Jennifer D.; Nachtigall, Paul E.; Au, Whitlow W. L.; Pawloski, Jeffrey L.; Roitblat, Herbert L.

    2003-01-01

    The Risso's dolphin (Grampus griseus) is an exclusively cephalopod-consuming delphinid with a distinctive vertical indentation along its forehead. To investigate whether or not the species echolocates, a female Risso's dolphin was trained to discriminate an aluminum cylinder from a nylon sphere (experiment 1) or an aluminum sphere (experiment 2) while wearing eyecups and free swimming in an open-water pen in Kaneohe Bay, Hawaii. The dolphin completed the task with little difficulty despite being blindfolded. Clicks emitted by the dolphin were acquired at average amplitudes of 192.6 dB re 1 μPa, with estimated sources levels up to 216 dB re 1 μPa-1 m. Clicks were acquired with peak frequencies as high as 104.7 kHz (Mfp=47.9 kHz), center frequencies as high as 85.7 kHz (Mf0=56.5 kHz), 3-dB bandwidths up to 94.1 kHz (MBW=39.7 kHz), and root-mean-square bandwidths up to 32.8 kHz (MRMS=23.3 kHz). Click durations were between 40 and 70 μs. The data establish that the Risso's dolphin echolocates, and that, aside from slightly lower amplitudes and frequencies, the clicks emitted by the dolphin were similar to those emitted by other echolocating odontocetes. The particular acoustic and behavioral findings in the study are discussed with respect to the possible direction of the sonar transmission beam of the species.

  6. Managing diversity: Domestication and gene flow in Stenocereus stellatus Riccob. (Cactaceae) in Mexico

    PubMed Central

    Cruse-Sanders, Jennifer M; Parker, Kathleen C; Friar, Elizabeth A; Huang, Daisie I; Mashayekhi, Saeideh; Prince, Linda M; Otero-Arnaiz, Adriana; Casas, Alejandro

    2013-01-01

    Microsatellite markers (N = 5) were developed for analysis of genetic variation in 15 populations of the columnar cactus Stenocereus stellatus, managed under traditional agriculture practices in central Mexico. Microsatellite diversity was analyzed within and among populations, between geographic regions, and among population management types to provide detailed insight into historical gene flow rates and population dynamics associated with domestication. Our results corroborate a greater diversity in populations managed by farmers compared with wild ones (HE = 0.64 vs. 0.55), but with regional variation between populations among regions. Although farmers propagated S. stellatus vegetatively in home gardens to diversify their stock, asexual recruitment also occurred naturally in populations where more marginal conditions have limited sexual recruitment, resulting in lower genetic diversity. Therefore, a clear-cut relationship between the occurrence of asexual recruitment and genetic diversity was not evident. Two managed populations adjacent to towns were identified as major sources of gene movement in each sampled region, with significant migration to distant as well as nearby populations. Coupled with the absence of significant bottlenecks, this suggests a mechanism for promoting genetic diversity in managed populations through long distance gene exchange. Cultivation of S. stellatus in close proximity to wild populations has led to complex patterns of genetic variation across the landscape that reflects the interaction of natural and cultural processes. As molecular markers become available for nontraditional crops and novel analysis techniques allow us to detect and evaluate patterns of genetic diversity, genetic studies provide valuable insights into managing crop genetic resources into the future against a backdrop of global change. Traditional agriculture systems play an important role in maintaining genetic diversity for plant species. PMID:23762520

  7. Transmission beam characteristics of a Risso's dolphin (Grampus griseus).

    PubMed

    Smith, Adam B; Kloepper, Laura N; Yang, Wei-Cheng; Huang, Wan-Hsiu; Jen, I-Fan; Rideout, Brendan P; Nachtigall, Paul E

    2016-01-01

    The echolocation system of the Risso's dolphin (Grampus griseus) remains poorly studied compared to other odontocete species. In this study, echolocation signals were recorded from a stationary Risso's dolphin with an array of 16 hydrophones and the two-dimensional beam shape was explored using frequency-dependent amplitude plots. Click source parameters were similar to those already described for this species. Centroid frequency of click signals increased with increasing sound pressure level, while the beamwidth decreased with increasing center frequency. Analysis revealed primarily single-lobed, and occasionally vertically dual-lobed, beam shapes. Overall beam directivity was found to be greater than that of the harbor porpoise, bottlenose dolphin, and a false killer whale. The relationship between frequency content, beam directivity, and head size for this Risso's dolphin deviated from the trend described for other species. These are the first reported measurements of echolocation beam shape and directivity in G. griseus. PMID:26827004

  8. Regulation of trehalose metabolism by Streptomyces griseus spores.

    PubMed Central

    McBride, M J; Ensign, J C

    1990-01-01

    Spores of Streptomyces griseus contain trehalose and trehalase, but trehalose is not readily hydrolyzed until spore germination is initiated. Trehalase in crude extracts of spores, germinated spores, and mycelia of S. griseus had a pH optimum of approximately 6.2, had a Km value for trehalose of approximately 11 mM, and was most active in buffers having ionic strengths of 50 to 200 mM. Inhibitors or activators or trehalase activity were not detected in extracts of spores or mycelia. Several lines of evidence indicated that trehalose and trehalase are both located in the spore cytoplasm. Spores retained their trehalose and most of their trehalase activity following brief exposure to dilute acid. Protoplasts formed by enzymatic removal of the spore walls in buffer containing high concentrations of solutes also retained their trehalose and trehalase activity. Protoplasts formed in buffer containing lower levels of solutes contained low levels of trehalose. The mechanism by which trehalose metabolism is regulated in S. griseus spores is unresolved. A low level of hydration of the cytoplasm of the dormant spores and an increased level of hydration during germination may account for the apparent inactivity of trehalase in dormant spores and the rapid hydrolysis of trehalose upon initiation of germination. Images PMID:2113908

  9. Quantification of polyphenols and flavonoid content and evaluation of anti-inflammatory and antimicrobial activities of Stenocereus stellatus extracts.

    PubMed

    Soto-Cabrera, Diego; Salazar, Juan R; Nogueda-Gutiérrez, Inés; Torres-Olvera, Mariana; Cerón-Nava, Anabelle; Rosales-Guevara, Juan; Terrazas, Teresa; Rosas-Acevedo, Hortensia

    2016-08-01

    The hexanic, ethyl acetate and methanolic extracts from branches of Stenocereus stellatus were tested in both the 12-O-tetradecanoylphorbol-13-acetate (TPA) - induced ear oedema model and antimicrobial activity assay. The % of oedema inhibition, the Minimum Inhibitory Concentration (MIC), as well as the polyphenolic and flavonoid content were determined. Also, extracts were analysed by gas chromatography-mass spectrometry (GC-MS). In TPA model, the three extracts showed moderate oedema inhibition. In the antimicrobial activity assay, methanolic extract shows better MIC against all strains. The lowest MICs were for Candida albicans (31 μg/mL) and Rhizopus sp. (15 μg/mL). Also, 50.78 mg eq. of gallic acid/g extract of polyphenol and 115.12 mg eq. of catequine/g extract of flavonoids content were founded in ethyl acetate extract. In the chromatographic analysis, β-sitosterol, β-amyrine, betulin and some other molecules were identified. The results show that S. stellatus possess antimicrobial activities against some fungus species. PMID:26395173

  10. Microbial colonization of injured cactus tissue (Stenocereus gummosus) and its relationship to the ecology of cactophilic Drosophila mojavensis.

    PubMed Central

    Fogleman, J C; Foster, J L

    1989-01-01

    Necrotic tissue of agria cactus (Stenocereus gummosus) serves as a feeding and breeding substrate for Drosophila mojavensis. This fly species is one of the four endemic Drosophila species in the Sonoran Desert. Freeze injuries were created in arms of agria cactus in Mexico to study the events of microbial colonization. Facultative anaerobic bacteria were the first microbes to be detected, and the exclusion of large arthropods by covering the injuries with netting did not affect bacterial colonization. Yeast growth lagged behind bacterial growth by 2 days, and excluding arthropods delayed the detection of yeasts by an additional 2 days. Thus, insects (such as Drosophila species) and other arthropods do play a role in the colonization of agria rots by yeasts. All injuries were attractive to D. mojavensis within 5 days, and these flies were shown to be carrying significant densities of both bacteria and yeasts. Analysis of the volatile compounds present in the developing rots over time indicated that the volatile pattern is dynamic. Ethanol and acetic acid were the two volatile substances most likely responsible for the initial attraction of the injuries for Drosophila species. PMID:2705763

  11. Engineering the primary substrate specificity of Streptomyces griseus trypsin.

    PubMed

    Page, Michael J; Wong, Sui-Lam; Hewitt, Jeff; Strynadka, Natalie C J; MacGillivray, Ross T A

    2003-08-01

    Streptomyces griseus trypsin (SGT) was chosen as a model scaffold for the development of serine proteases with enhanced substrate specificity. Recombinant SGT has been produced in a Bacillus subtilis expression system in a soluble active form and purified to homogeneity. The recombinant and native proteases have nearly identical enzymatic properties and structures. Four SGT mutants with alterations in the S1 substrate binding pocket (T190A, T190P, T190S, and T190V) were also expressed. The T190P mutant demonstrated the largest shift to a preference for Arg versus Lys in the P1 site. This was shown by a minor reduction in catalytic activity toward an Arg-containing substrate (k(cat) reduction of 25%). The crystal structures of the recombinant SGT and the T190P mutant in a complex with the inhibitor benzamidine were obtained at high resolution (approximately 1.9 A). The increase in P1 specificity, achieved with minimal effect on the catalytic efficiency, demonstrates that the T190P mutant is an ideal candidate for the design of additional substrate specificity engineered into the S2 to S4 binding pockets. PMID:12885239

  12. Purification and characterization of Streptomyces griseus metalloendopeptidases I and II.

    PubMed

    Tsuyuki, H; Kajiwara, K; Fujita, A; Kumazaki, T; Ishii, S

    1991-09-01

    Two metalloendopeptidases, designated as Streptomyces griseus metalloendopeptidases I and II (SGMPI and SGMPII), were isolated from a commercial Pronase P by a method including affinity chromatography on carbobenzoxy-L-alaninyl-triethylenetetraminyl-Sepharose (Z-Ala-T-Sepharose). The two enzymes differed from each other in behavior on ion-exchange chromatography but showed the same amino-terminal sequence at least up to the 20th residue. Their molecular weights were both estimated to be 37,000 by SDS-polyacrylamide gel electrophoresis. Elemental and amino acid composition analyses indicated that both of them contained about 1 g atom of zinc and one cystine residue per mol of protein. Cleavage specificities of the two enzymes toward synthetic peptide-substrates were very similar to those observed with thermolysin. EDTA, o-phenanthroline, and phosphoramidon strongly inhibited these enzymes, while typical serine-protease inhibitors and cysteine-protease inhibitors had no effect. The findings clearly indicate that SGMPI and SGMPII can be classified into the family of zinc-endopeptidases. It was unexpectedly found, however, that these metalloendopeptidases were strongly inhibited by protein serine-protease inhibitors produced by Streptomycetes, such as Streptomyces subtilisin inhibitor (SSI), alkaline protease inhibitor-2c' (API-2c'), and plasminostreptin (PS). PMID:1769959

  13. Studies on biological reduction of chromate by Streptomyces griseus.

    PubMed

    Poopal, Ashwini C; Laxman, R Seeta

    2009-09-30

    Chromium is a toxic heavy metal used in various industries and leads to environmental pollution due to improper handling. The most toxic form of chromium Cr(VI) can be converted to less toxic Cr(III) by reduction. Among the actinomycetes tested for chromate reduction, thirteen strains reduced Cr(VI) to Cr(III), of which one strain of Streptomyces griseus (NCIM 2020) was most efficient showing complete reduction within 24h. The organism was able to use a number of carbon sources as electron donors. Sulphate, nitrate, chloride and carbonate had no effect on chromate reduction during growth while cations such as Cd, Ni, Co and Cu were inhibitory to varying degrees. Chromate reduction was associated with the bacterial cells and sonication was the best method of cell breakage to release the enzyme. The enzyme was constitutive and did not require presence of chromate during growth for expression of activity. Chromate reduction with cell free extract (CFE) was observed without added NADH. However, addition of NAD(P)H resulted in 2-3-fold increase in activity. Chromate reductase showed optimum activity at 28 degrees C and pH 7. PMID:19410364

  14. [Lysis of the cell walls of streptococcus group A by Streptomyces griseus pronase].

    PubMed

    Savel'ev, E P; Petrov, G I

    1978-01-01

    The effect of Streptomyces griseus pronase on Streptococcus group A cell walls was studied. Cell walls were shown to be lysed by pronase, the lysis level being dependent on the molarity of the potassium-phosphate buffer used. With an increase in the buffer molarity from 0.005 M to 0.05 M lysis of cell walls decreased from 70-80% to 30%. By DEAE-cellulose chromatography lysates were separated into two fractions the first of which contained a group specific polysaccharide. A preparative method of obtaining a group specific polysaccharide of Streptococcus group A using Streptomyces griseus pronase under mild conditions is described. PMID:416431

  15. DISSEMINATED TOXOPLASMOSIS IN A MEDITERRANEAN PREGNANT RISSO'S DOLPHIN (GRAMPUS GRISEUS) WITH TRANSPLACENTAL FETAL INFECTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fatal disseminated toxoplasmosis was diagnosed in a Risso's dolphin (Grampus griseus) dam and its fetus based on pathologic findings, immunohistochemistry, and the structure of the parasite. The dolphin was stranded alive on the Spanish Mediterranean coast, and died a few hrs later. At necropsy the ...

  16. Purification of an antifungal endochitinase from a potential biocontrol Agent Streptomyces griseus.

    PubMed

    Rabeeth, M; Anitha, A; Srikanth, Geetha

    2011-08-15

    Streptomyces griseus (MTCC 9723) is a chitinolytic bacterium isolated from prawn cultivated pond soil of Peddapuram Village; East Godavari District was studied in detailed. Chitinase (EC 3.2.1.14) was extracted from the culture filtrate of Streptomyces griseus and purified by ammonium sulfate precipitation, DEAE-cellulose ionexchange chromatography, Sephadex G-100 and Sephadex G-200 gel filtration chromatography. The molecular mass of the purified chitinase was estimated to be 34, 32 kDa by SDS gel electrophoresis and confirmed by activity staining with Calcofluor White M2R. Chitinase was optimally active at pH of 6.0 and at 40 degrees C. The enzyme was stable from pH 5-9 and up to 20-50 degrees C. The chitinase exhibited Km and Vmax values of 400 mg and 180 IU mL(-1) for colloidal chitin. Among the metals and inhibitors that were tested, the Hg+, Hg2+ and P-chloromercuribenzoic acid completely inhibited the chitinase activity at 1 mM concentration. The purified chitinase showed high activity on colloidal chitin, chitobiose, and chitooligosaccharide. An in vitro assay proved that the crude chitinase, actively growing cells of S. griseus having antifungal activity against all studied fungal pathogen. This result implies that characteristics of S. griseus producing endochitinase made them suitable for biotechnological purpose such as for degradation of chitin containing waste and it might be a promising biocontrol agent for plant pathogens. PMID:22545353

  17. Interaction of trypsin-like protease from Streptomyces griseus with an immobilized inhibitor from kidney bean.

    PubMed

    Mosolov, V V; Fedurkina, N V; Valueva, T A

    1978-01-12

    An immobilized double-headed inhibitor from Phaseolus vulgaris L. selectively binds the trypsin-like enzyme produced by Streptomyces griseus. Binding takes place at pH 8.0, and at pH 2.0 the protease can be quantitatively released from the complex. Purified by affinity chromatography, the trypsin-like enzyme is homogeneous according to polyacrylamide gel electrophoresis and ultracentrifugation data. Physico-chemical and enzymic properties of the enzyme are identical to those exhibited by the enzyme purified by ion-exchange chromatography. Chymoelastases from Str. griseus as well as the subtilisin-like enzyme do not interact with an immobilized inhibitor. In solution, the inhibitor from P. vulgaris gives a stable ternary complex with bovine trypsin and chymotrypsin, whereas with an immobilized inhibitor the trypsin, if present, tends to displace chymotrypsin in an chymotrypsin inhibitor complex. This evidence suggests that immobilization results in considerable changes in inhibitor properties. PMID:413581

  18. Molecular characterization of a gene encoding a photolyase from Streptomyces griseus.

    PubMed Central

    Kobayashi, T; Takao, M; Oikawa, A; Yasui, A

    1989-01-01

    By using a synthetic DNA probe derived from an amino acid sequence in the most conserved region of three known photolyases (Escherichia coli, Anacystis nidulans and Saccharomyces cerevisiae), we isolated a DNA fragment containing two long open reading frames (ORFs) from a genomic DNA library of Streptomyces griseus. One ORF encodes a polypeptide of 455 amino acids (Mr 50594), which exhibits substantial similarities with the other three photolyases. Photoreactivation-repair deficient E. coli cells could be converted into photoreactivatable ones by introduction of plasmids harboring this ORF, indicating that this is the photolyase gene of S. griseus. The deduced aa sequence of Streptomyces photolyase was most similar to that of E. coli. The putative DNA binding site as well as cofactor binding regions were proposed. Images PMID:2501760

  19. Transcriptional Control by A-Factor of Two Trypsin Genes in Streptomyces griseus

    PubMed Central

    Kato, Jun-ya; Chi, Won-Jae; Ohnishi, Yasuo; Hong, Soon-Kwang; Horinouchi, Sueharu

    2005-01-01

    AdpA is the key transcriptional activator for a number of genes of various functions in the A-factor regulatory cascade in Streptomyces griseus, forming an AdpA regulon. Trypsin-like activity was detected at a late stage of growth in the wild-type strain but not in an A-factor-deficient mutant. Consistent with these observations, two trypsin genes, sprT and sprU, in S. griseus were found to be members of the AdpA regulon; AdpA activated the transcription of both genes by binding to the operators located at about −50 nucleotide positions with respect to the transcriptional start point. The transcription of sprT and sprU, induced by AdpA, was most active at the onset of sporulation. Most trypsin activity exerted by S. griseus was attributed to SprT, because trypsin activity in an sprT-disrupted mutant was greatly reduced but that in an sprU-disrupted mutant was only slightly reduced. This was consistent with the observation that the amount of the sprT mRNA was much greater than that of the sprU transcript. Disruption of both sprT and sprU (mutant ΔsprTU) reduced trypsin activity to almost zero, indicating that no trypsin genes other than these two were present in S. griseus. Even the double mutant ΔsprTU grew normally and developed aerial hyphae and spores over the same time course as the wild-type strain. PMID:15601713

  20. Genome Sequence of the Streptomycin-Producing Microorganism Streptomyces griseus IFO 13350▿ †

    PubMed Central

    Ohnishi, Yasuo; Ishikawa, Jun; Hara, Hirofumi; Suzuki, Hirokazu; Ikenoya, Miwa; Ikeda, Haruo; Yamashita, Atsushi; Hattori, Masahira; Horinouchi, Sueharu

    2008-01-01

    We determined the complete genome sequence of Streptomyces griseus IFO 13350, a soil bacterium producing an antituberculosis agent, streptomycin, which is the first aminoglycoside antibiotic, discovered more than 60 years ago. The linear chromosome consists of 8,545,929 base pairs (bp), with an average G+C content of 72.2%, predicting 7,138 open reading frames, six rRNA operons (16S-23S-5S), and 66 tRNA genes. It contains extremely long terminal inverted repeats (TIRs) of 132,910 bp each. The telomere's nucleotide sequence and secondary structure, consisting of several palindromes with a loop sequence of 5′-GGA-3′, are different from those of typical telomeres conserved among other Streptomyces species. In accordance with the difference, the chromosome has pseudogenes for a conserved terminal protein (Tpg) and a telomere-associated protein (Tap), and a novel pair of Tpg and Tap proteins is instead encoded by the TIRs. Comparisons with the genomes of two related species, Streptomyces coelicolor A3(2) and Streptomyces avermitilis, clarified not only the characteristics of the S. griseus genome but also the existence of 24 Streptomyces-specific proteins. The S. griseus genome contains 34 gene clusters or genes for the biosynthesis of known or unknown secondary metabolites. Transcriptome analysis using a DNA microarray showed that at least four of these clusters, in addition to the streptomycin biosynthesis gene cluster, were activated directly or indirectly by AdpA, which is a central transcriptional activator for secondary metabolism and morphogenesis in the A-factor (a γ-butyrolactone signaling molecule) regulatory cascade in S. griseus. PMID:18375553

  1. An ABC transporter involved in the control of streptomycin production in Streptomyces griseus.

    PubMed

    Takano, Hideaki; Toriumi, Naoe; Hirata, Mariko; Amano, Taisuke; Ohya, Takaaki; Shimada, Reona; Kusada, Hiroyuki; Amano, Sho-Ichi; Matsuda, Ko-Ichi; Beppu, Teruhiko; Ueda, Kenji

    2016-07-01

    We screened for a gene that inhibits streptomycin production in Streptomyces griseus when it is introduced on a high-copy-number plasmid pIJ702, and obtained a plasmid pKM545. The introduction of pKM545 abolished streptomycin production on all media tested including YMP-sugar and Nutrient broth. S1 protection analysis demonstrated that the introduction of this plasmid downregulated the transcriptional activity of the promoter preceding strR, the pathway-specific transcriptional regulator for streptomycin biosynthesis. The 2.8-kb BamHI fragment cloned onto pKM545 contained two coding sequences SGR_5442 and 5443. These coding sequences and the two downstream ones (SGR_5444 and 5445) constituted a possible operon structure designated to be rspABCD (regulation of streptomycin production). RspB and RspC exhibited a marked similarity with an ATP-binding domain and a membrane-associating domain of an ABC-2 type transporter, respectively, suggesting that the Rsp proteins comprise a membrane exporter. The gene cluster consisting of the rsp operon and the upstream divergent small coding sequence (SGR_5441) was widely distributed to Streptomyces genome. An rspB mutant of S. griseus produced 3-fold streptomycin of the parental strain in YMP liquid medium. The evidence implies that the Rsp translocator is involved in the export of a substance that specifies the expression level of streptomycin biosynthesis genes in S. griseus. PMID:27268270

  2. Detection and properties of A-factor-binding protein from Streptomyces griseus

    SciTech Connect

    Miyake, K.; Horinouchi, S.; Yoshida, M.; Chiba, N.; Mori, K.; Nogawa, N.; Morikawa, N.; Beppu, T. )

    1989-08-01

    The optically active form of tritium-labeled A-factor (2-isocapryloyl-3R-hydroxymethyl-gamma-butyrolactone), a pleiotropic autoregulator responsible for streptomycin production, streptomycin resistance, and sporulation in Streptomyces griseus, was chemically synthesized. By using the radioactive A-factor, a binding protein for A-factor was detected in the cytoplasmic fraction of this organism. The binding protein had an apparent molecular weight of approximately 26,000, as determined by gel filtration. Scatchard analysis suggested that A-factor bound the protein in the molar ratio of 1:1 with a binding constant, Kd, of 0.7 nM. The number of the binding protein was roughly estimated to be 37 per genome. The inducing material virginiae butanolide C (VB-C), which has a structure very similar to that of A-factor and is essential for virginiamycin production in Streptomyces virginiae, did not inhibit binding. In addition, no protein capable of specifically binding {sup 3}H-labeled VB-C was found in S. griseus. Together with the observation that VB-C had almost no biological activity on the restoration of streptomycin production or sporulation in an A-factor-deficient mutant of S. griseus, these results indicated that the binding protein had a strict ligand specificity. Examination for an A-factor-binding protein in Streptomyces coelicolor A3(2) and Streptomyces lividans showed the absence of any specifically binding protein.

  3. Multicentric Benign Epithelial Inclusions in a Free-ranging Risso's Dolphin (Grampus griseus).

    PubMed

    Diaz-Delgado, J; Quesada-Canales, O; Arbelo, M; Sierra, E; Edwards, J F; Suarez-Bonnet, A; Santana-Suarez, C; Espinosa de Los Monteros, A; Fernandez, A

    2016-01-01

    This report describes the histological and immunohistochemical features of multicentric, benign, epithelial inclusions (BEIs) in a free-ranging, adult, female Risso's dolphin (Grampus griseus). The differential diagnoses included ectopic hamartomatous epithelial inclusions, non-Müllerian choristoma, Müllerian choristoma and low-grade metastatic carcinoma/mesothelioma. The most likely diagnosis of such BEIs was multicentric, embolic, reactive mesothelium, as suggested by cytomorphological and immunophenotypical features of the BEIs, the occurrence of focal pleural rupture and the immunophenotype of the pleural mesothelium. The former represents a pathological condition not previously reported in a marine mammal species, rarely described in animals, and relatively infrequently recognized in man. PMID:27392421

  4. Synthetic analogues of chymostatin. Inhibition of chymotrypsin and Streptomyces griseus proteinase A.

    PubMed Central

    Tomkinson, N P; Galpin, I J; Beynon, R J

    1992-01-01

    A series of analogues of chymostatin, including Z-Arg-Leu-Phe-aldehyde (Z-Arg-Leu-Phe-H), have been synthesized. Analysis of the inhibitory potential of these analogues permits identification of residues and interactions that are important for inhibitory activity. Moreover, the structure-function relationship for Z-Arg-Leu-Phe-H and chymostatin inhibition of chymotrypsin and Streptomyces griseus proteinase A (SGPA) was probed further with the aid of molecular mechanics. This analysis identified interactions that provide an explanation for the enhanced activity of the natural product, chymostatin, over the synthetic analogues in the inhibition of chymotrypsin but not SGPA. PMID:1530579

  5. Differential Regulation of ftsZ Transcription during Septation of Streptomyces griseus

    PubMed Central

    Kwak, Jangyul; Dharmatilake, Amitha J.; Jiang, Hao; Kendrick, Kathleen E.

    2001-01-01

    Streptomyces has been known to form two types of septa. The data in this research demonstrated that Streptomyces griseus forms another type of septum near the base of sporogenic hyphae (basal septum). To understand the regulation of the septation machinery in S. griseus, we investigated the expression of the ftsZ gene. S1 nuclease protection assays revealed that four ftsZ transcripts were differentially expressed during morphological differentiation. The vegetative transcript (emanating from Pveg) is present at a moderate level during vegetative growth, but is switched off within the first 2 h of sporulation. Two sporulation-specific transcripts predominantly accumulated, and the levels increased by approximately fivefold together shortly before sporulation septa begin to form. Consistently, the sporulation-specific transcripts were expressed much earlier and more abundantly in a group of nonsporulating mutants that form their sporulation septa prematurely. Promoter-probe studies with two different reporter systems confirmed the activities of the putative promoters identified from the 5′ end point of the transcripts. The levels and expression timing of promoter activities were consistent with the results of nuclease protection assays. The aseptate phenotype of the Pspo mutant indicated that the increased transcription from Pspo is required for sporulation septation, but not for vegetative or basal septum formation. PMID:11489862

  6. Purification of histidase from Streptomyces griseus and nucleotide sequence of the hutH structural gene.

    PubMed Central

    Wu, P C; Kroening, T A; White, P J; Kendrick, K E

    1992-01-01

    Histidine ammonia-lyase (histidase) was purified to homogeneity from vegetative mycelia of Streptomyces griseus. The enzyme was specific for L-histidine and showed no activity against the substrate analog, D-histidine. Histidinol phosphate was a potent competitive inhibitor. Histidase displayed saturation kinetics with no detectable sigmoidal response. Neither thiol reagents nor a variety of divalent cations had any effect on the activity of the purified enzyme. High concentrations of potassium cyanide inactivated histidase in the absence of its substrate or histidinol phosphate, suggesting that, as in other histidases, dehydroalanine plays an important role in catalysis. The N-terminal amino acid sequence of histidase was used to construct a mixed oligonucleotide probe to identify and clone the histidase structural gene, hutH, from genomic DNA of the wild-type strain of S. griseus. The cloned DNA restored the ability of a histidase structural gene mutant to grow on L-histidine as the sole nitrogen source. The deduced amino acid sequence of hutH shows significant relatedness with histidase from bacteria and a mammal as well as phenylalanine ammonia-lyase from plants and fungi. Images PMID:1537807

  7. Molecular cloning of tetracycline resistance genes from Streptomyces rimosus in Streptomyces griseus and characterization of the cloned genes.

    PubMed Central

    Ohnuki, T; Katoh, T; Imanaka, T; Aiba, S

    1985-01-01

    Two tetracycline resistance genes of Streptomyces rimosus, an oxytetracycline producer, were cloned in Streptomyces griseus by using pOA15 as a vector plasmid. Expression of the cloned genes, designated as tetA and tetB was inducible in S. griseus as well as in the donor strain. The tetracycline resistance directed by tetA and tetB was characterized by examining the uptake of tetracycline and in vitro polyphenylalanine synthesis by the sensitive host and transformants with the resultant hybrid plasmids. Polyphenylalanine synthesis with crude ribosomes and the S150 fraction from S. griseus carrying the tetA plasmid was resistant to tetracycline, and, by a cross-test of ribosomes and S150 fraction coming from both the sensitive host and the resistant transformant, the resistance directed by tetA was revealed to reside mainly in crude ribosomes and slightly in the S150 fraction. However, the resistance in the crude ribosomes disappeared when they were washed with 1 M ammonium chloride. These results suggest that tetA specified the tetracycline resistance of the machinery for protein synthesis not through ribosomal subunits, but via an unidentified cytoplasmic factor. In contrast, S. griseus carrying the tetB plasmid accumulated less intracellular tetracycline than did the host, and the protein synthesis by reconstituting the ribosomes and S150 fraction was sensitive to the drug. Therefore, it is conceivable that tetB coded a tetracycline resistance determinant responsible for the reduced accumulation of tetracycline. Images PMID:2982781

  8. Evolution under domestication: ongoing artificial selection and divergence of wild and managed Stenocereus pruinosus (Cactaceae) populations in the Tehuacán Valley, Mexico

    PubMed Central

    Parra, Fabiola; Casas, Alejandro; Peñaloza-Ramírez, Juan Manuel; Cortés-Palomec, Aurea C.; Rocha-Ramírez, Víctor; González-Rodríguez, Antonio

    2010-01-01

    Background and Aims The Tehuacán Valley in Mexico is a principal area of plant domestication in Mesoamerica. There, artificial selection is currently practised on nearly 120 native plant species with coexisting wild, silvicultural and cultivated populations, providing an excellent setting for studying ongoing mechanisms of evolution under domestication. One of these species is the columnar cactus Stenocereus pruinosus, in which we studied how artificial selection is operating through traditional management and whether it has determined morphological and genetic divergence between wild and managed populations. Methods Semi-structured interviews were conducted with 83 households of three villages to investigate motives and mechanisms of artificial selection. Management effects were studied by comparing variation patterns of 14 morphological characters and population genetics (four microsatellite loci) of 264 plants from nine wild, silvicultural and cultivated populations. Key Results Variation in fruit characters was recognized by most people, and was the principal target of artificial selection directed to favour larger and sweeter fruits with thinner or thicker peel, fewer spines and pulp colours others than red. Artificial selection operates in agroforestry systems favouring abundance (through not felling plants and planting branches) of the preferred phenotypes, and acts more intensely in household gardens. Significant morphological divergence between wild and managed populations was observed in fruit characters and plant vigour. On average, genetic diversity in silvicultural populations (HE = 0·743) was higher than in wild (HE = 0·726) and cultivated (HE = 0·700) populations. Most of the genetic variation (90·58 %) occurred within populations. High gene flow (NmFST > 2) was identified among almost all populations studied, but was slightly limited by mountains among wild populations, and by artificial selection among wild and managed populations. Conclusions

  9. Aeromonas dhakensis pneumonia and sepsis in a neonate Risso's dolphin Grampus griseus from the Mediterranean Sea.

    PubMed

    Pérez, Lola; Abarca, M Lourdes; Latif-Eugenín, Fadua; Beaz-Hidalgo, Roxana; Figueras, M José; Domingo, Mariano

    2015-09-17

    A neonate Risso's dolphin Grampus griseus was found stranded alive on a beach in Catalonia, Spain. Rehabilitation attempts were unsuccessful and it died 2 d later, showing pneumonia and sepsis. A pure bacterial culture was obtained from all tissues and blood and identified as Aeromonas hydrophila using the API 20NE. However, sequencing the rpoD gene showed that the strain in fact belongs to A. dhakensis, making this the first report of fatal haemorrhagic-necrotizing pneumonia and sepsis due to this species in a marine mammal. The A. dhakensis strain GMV-704 produced β-haemolysis, possessed several virulence genes and showed sensitivity to several antimicrobials. This study provides a new potential host for A. dhakensis, and its potential virulence in dolphins and its presence in the marine environment may warrant considering this species a potential threat to marine mammals. PMID:26378409

  10. Interactions of Streptomyces serine-protease inhibitors with Streptomyces griseus metalloendopeptidase II.

    PubMed

    Kajiwara, K; Fujita, A; Tsuyuki, H; Kumazaki, T; Ishii, S

    1991-09-01

    Streptomyces griseus metalloendopeptidase II (SGMPII) was shown to form tight complexes with several Streptomyces protein inhibitors which had been believed to be specific to serine proteases, such as Streptomyces subtilisin inhibitor (SSI), plasminostreptin (PS), and alkaline protease inhibitor-2c' (API-2c'), as well as with Streptomyces metalloprotease inhibitor (SMPI). The dissociation constants of complexes between SGMPII and these inhibitors were successfully determined by using a novel fluorogenic bimane-peptide substrate. The values ranged from nM to pM. The results of studies by gel chromatographic and enzymatic analyses indicated that SGMPII is liberated from the complex with SSI by the addition of subtilisin BPN'. SGMPII and subtilisin BPN' proved, therefore, to interact with SSI in a competitive manner, despite the difference in the chemical nature of their active sites. PMID:1769961

  11. A modular family 19 chitinase found in the prokaryotic organism Streptomyces griseus HUT 6037.

    PubMed Central

    Ohno, T; Armand, S; Hata, T; Nikaidou, N; Henrissat, B; Mitsutomi, M; Watanabe, T

    1996-01-01

    The specificity of chitinase C-1 of Streptomyces griseus HUT 6037 for the hydrolysis of the beta-1,4-glycosidic linkages in partially acetylated chitosan is different from that of other microbial chitinases. In order to study the primary structure of this unique chitinase, the chiC gene specifying chitinase C-1 was cloned and its nucleotide sequence was determined. The gene encodes a polypeptide of 294 amino acids with a calculated size of 31.4 kDa. Comparison of the amino acid sequence of the deduced polypeptide with that of other proteins revealed a C-terminal catalytic domain displaying considerable sequence similarity to the catalytic domain of plant class I, II, and IV chitinases which form glycosyl hydrolase family 19. The N-terminal domain of the deduced polypeptide exhibits sequence similarity to substrate-binding domains of several microbial chitinases and cellulases but not to the chitin-binding domains of plant chitinases. The previously purified chitinase C-1 from S. griseus is suggested to be generated by proteolytic removal of the N-terminal chitin-binding domain and corresponds to the catalytic domain of the chitinase encoded by the chiC gene. High-performance liquid chromatography analysis of the hydrolysis products from N-acetyl chitotetraose revealed that chitinase C-1 catalyzes hydrolysis of the glycosidic bond with inversion of the anomeric configuration, in agreement with the previously reported inverting mechanism of plant class I chitinases. This is the first report of a family 19 chitinase found in an organism other than higher plants. PMID:8752320

  12. Biofiltration technology for the removal of toluene from polluted air using Streptomyces griseus.

    PubMed

    Mohamed, Elham F; Awad, Gamal; Andriantsiferana, Caroline; El-Diwany, Ahmed I

    2016-05-01

    Biofiltration technology has been recognized as a promising biotechnology for treating the volatile organic compounds (VOCs) present in polluted air. This study aims to investigate the performance of a biofiltration system of Streptomyces griseus sp. DSM-40759 immobilized on activated carbon (PICA S23) towards the adsorption and degradation of toluene vapour as well as to regenerate the activated carbon in situ. The batch studies were performed using nutrient agar medium and basal salt medium (BSM) for microbial growth. Initially the pre-cultures were incubated at a temperature of 28°C on a rotary shaker at 150 rpm. After two days, the strain S. griseus DSM-40759 was immobilized on a known weight of activated carbon (12 g). The results of biofilter performance showed three different stages with a quick adsorption phase with approximately 95% of toluene removal after 70 min, a slow biotransformation phase by immobilized cells. In the later, the removal efficiency decreased significantly with the extension of time and reached 60% during this stage. Moreover, a final quick removal phase by the immobilized cells had an average removal efficiency of toluene around 95% after 500 min. The toluene degradation was found to be more than 84% after the second cycle and the biofilter was still capable of removing additional toluene. Thus, the results demonstrated the feasibility and reusability of a new biofilter system for toluene removal as well as extending the activated carbon's capacity and this could be a potential solution to reuse the activated carbon in industrial application. PMID:26469210

  13. Landscape management and domestication of Stenocereus pruinosus (Cactaceae) in the Tehuacán Valley: human guided selection and gene flow

    PubMed Central

    2012-01-01

    Background Use of plant resources and ecosystems practiced by indigenous peoples of Mesoamerica commonly involves domestication of plant populations and landscapes. Our study analyzed interactions of coexisting wild and managed populations of the pitaya Stenocereus pruinosus, a columnar cactus used for its edible fruit occurring in natural forests, silviculturally managed in milpa agroforestry systems, and agriculturally managed in homegardens of the Tehuacán Valley, Mexico. We aimed at analyzing criteria of artificial selection and their consequences on phenotypic diversity and differentiation, as well as documenting management of propagules at landscape level and their possible contribution to gene flow among populations. Methods Semi-structured interviews were conducted to 83 households of the region to document perception of variation, criteria of artificial selection, and patterns of moving propagules among wild and managed populations. Morphological variation of trees from nine wild, silviculturally and agriculturally managed populations was analyzed for 37 characters through univariate and multivariate statistical methods. In addition, indexes of morphological diversity (MD) per population and phenotypic differentiation (PD) among populations were calculated using character states and frequencies. Results People recognized 15 pitaya varieties based on their pulp color, fruit size, form, flavor, and thorniness. On average, in wild populations we recorded one variety per population, in silviculturally managed populations 1.58 ± 0.77 varieties per parcel, and in agriculturally managed populations 2.19 ± 1.12 varieties per homegarden. Farmers select in favor of sweet flavor (71% of households interviewed) and pulp color (46%) mainly red, orange and yellow. Artificial selection is practiced in homegardens and 65% of people interviewed also do it in agroforestry systems. People obtain fruit and branches from different population types and move

  14. Accumulation of silicon in cacti native to the United States: characterization of silica bodies and cyclic oligosiloxanes in Stenocereus thurberi, Opuntia littoralis, Opuntia ficus-indica, and Opuntia stricta.

    PubMed

    Wright, Cynthia R; Waddell, Emanuel A; Setzer, William N

    2014-06-01

    Four different cactus species growing in the United States, Stenocereus thurberi growing in Organ Pipe Cactus National Monument, Arizona, Opuntia littoralis and Opuntia ficus-indica, growing on Santa Catalina Island, California, and Opuntia stricta, growing in northern Alabama, were examined for the presence of silica bodies (opaline phytoliths). Silica bodies were found in all four of these cactus species, parallelepiped-shaped crystals in S. thurberi, and starburst-shaped crystalline structures in the three Opuntia species. In addition, the essential oils of the four cactus species were obtained by hydrodistillation and analyzed by gas chromatography - mass spectrometry. To our surprise, S. thurberi, O. littoralis, and O. ficus-indica (but not O. stricta) essential oils contained cyclic oligosiloxanes. To our knowledge, cyclic oligosiloxanes have not been previously found as essential oil components. PMID:25115104

  15. Hearing abilities and sound reception of broadband sounds in an adult Risso's dolphin (Grampus griseus).

    PubMed

    Mooney, T Aran; Yang, Wei-Cheng; Yu, Hsin-Yi; Ketten, Darlene R; Jen, I-Fan

    2015-08-01

    While odontocetes do not have an external pinna that guides sound to the middle ear, they are considered to receive sound through specialized regions of the head and lower jaw. Yet odontocetes differ in the shape of the lower jaw suggesting that hearing pathways may vary between species, potentially influencing hearing directionality and noise impacts. This work measured the audiogram and received sensitivity of a Risso's dolphin (Grampus griseus) in an effort to comparatively examine how this species receives sound. Jaw hearing thresholds were lowest (most sensitive) at two locations along the anterior, midline region of the lower jaw (the lower jaw tip and anterior part of the throat). Responses were similarly low along a more posterior region of the lower mandible, considered the area of best hearing in bottlenose dolphins. Left- and right-side differences were also noted suggesting possible left-right asymmetries in sound reception or differences in ear sensitivities. The results indicate best hearing pathways may vary between the Risso's dolphin and other odontocetes measured. This animal received sound well, supporting a proposed throat pathway. For Risso's dolphins in particular, good ventral hearing would support their acoustic ecology by facilitating echo-detection from their proposed downward oriented echolocation beam. PMID:25925434

  16. Improved Production of Active Streptomyces griseus Trypsin with a Novel Auto-Catalyzed Strategy

    PubMed Central

    Zhang, Yunfeng; Ling, Zhenmin; Du, Guocheng; Chen, Jian; Kang, Zhen

    2016-01-01

    N-terminal sequences play crucial roles in regulating expression, translation, activation and enzymatic properties of proteins. To reduce cell toxicity of intracellular trypsin and increase secretory expression, we developed a novel auto-catalyzed strategy to produce recombinant trypsin by engineering the N-terminus of mature Streptomyces griseus trypsin (SGT). The engineered N-terminal peptide of SGT was composed of the thioredoxin, glycine-serine linker, His6-tag and the partial bovine trypsinogen pro-peptide (DDDDK). Furthermore, we constructed a variant TLEI with insertion of the artificial peptide at N-terminus and site-directed mutagenesis of the autolysis residue R145. In fed-batch fermentation, the production of extracellular trypsin activity was significantly improved to 47.4 ± 1.2 U·ml−1 (amidase activity, 8532 ± 142.2 U·ml−1 BAEE activity) with a productivity of 0.49 U·ml−1·h−1, which was 329% greater than that of parent strain Pichia pastoris GS115-SGT. This work has significant potential to be scaled-up for microbial production of SGT. In addition, the N-terminal peptide engineering strategy can be extended to improve heterologous expression of other toxic enzymes. PMID:26983398

  17. Faeriefungin: a new broad-spectrum antibiotic from Streptomyces griseus var. autotrophicus.

    PubMed

    Nair, M G; Putnam, A R; Mishra, S K; Mulks, M H; Taft, W H; Keller, J E; Miller, J R; Zhu, P P; Meinhart, J D; Lynn, D G

    1989-01-01

    Faeriefungin, a polyol polyene macrolide lactone antibiotic, was isolated from the mycelium of Streptomyces griseus var. autotrophicus, MSU-32058/ATCC 53668, collected from the soil sample of a fairy ring in an old lawn in Lansing, Michigan. Faeriefungin has some properties similar to the previously reported polyene macrolides, mycoticin and flavofungin, but possesses different physiochemical and biological properties. Aspergillus, Fusarium, Microsporum, Trichophyton, and Alternaria spp. were completely inhibited by faeriefungin at 3.2 micrograms/ml, Candida spp. at 5.5 micrograms/ml, and Pythium, Phialophora, Leptosphaeria spp., and some selected Gram-negative penicillin-resistant strains of Neisseria gonorrhoeae at 16.0 micrograms/ml. At a concentration of 100 ppm, it caused 100% mortality of mosquito larvae (Aedes aegypti, Rockefeller strain) and free-living nematodes (Panagrellus redivivus). Unlike the related polyene macrolides, faeriefungin is crystalline and stable with broad-spectrum antimicrobial and insecticidal activity. Preliminary cytotoxicity studies with human erythrocytes and rat liver epithelial cells indicated that faeriefungin and amphotericin B have comparable toxicity. Solution nmr study has indicated that faeriefungin is a mixture of two compounds, faerifungins A [1] and B [2], and that they differ in the attachment of a H or an Me at C-33. PMID:2509636

  18. Evidence suggests vocal production learning in a cross-fostered Risso's dolphin (Grampus griseus).

    PubMed

    Favaro, Livio; Neves, Silvana; Furlati, Stefano; Pessani, Daniela; Martin, Vidal; Janik, Vincent M

    2016-07-01

    Vocal learning is a rare skill in mammals, and we have limited information about the contexts in which they use it. Previous studies suggested that cetaceans in general are skilled at imitating sounds, but only few species have been studied to date. To expand this investigation to another species and to investigate the possible influence of the social environment on vocal learning, we studied the whistle repertoire of a female Risso's dolphin (Grampus griseus) that was stranded at an early age and was subsequently raised in a group of bottlenose dolphins (Tursiops truncatus). We show that this cross-fostered animal produced vocal signals more akin to those of its Tursiops poolmates than those of Risso's dolphins in the wild. This is one of very few systematic cross-fostering studies in cetaceans and the first to suggest vocal production learning in the Risso's dolphin. Our findings also suggest that social experience is a major factor in the development of the vocal repertoire in this species. PMID:26874843

  19. Inhibition of Streptomyces griseus metallo-endopeptidase II (SGMPII) by active-site-directed inhibitors.

    PubMed

    Kumazaki, T; Ishii, S; Yokosawa, H

    1994-03-01

    Inactivation of Streptomyces griseus metallo-endopeptidase II (SGMPII) by ClCH2CO-DL-(N-OH)Leu-OCH3 and by ClCH2CO-DL-(N-OH)Leu-Ala-Gly-NH2 was studied kinetically. These reagents cause irreversible inhibition of the enzyme in a pseudo-first order reaction, and the inhibition reaction exhibits saturation kinetics. The second-order rate constants for inactivation of SGMPII by ClCH2CO-DL-(N-OH)Leu-OCH3 and by ClCH2CO-DL-(N-OH)Leu-Ala-Gly-NH2 were measured to be 0.12 and 8.9 M-1.s-1, respectively. The order of affinities of metallo-endopeptidases towards these irreversible inhibitors is thermolysin > SGMPII > Pseudomonas aeruginosa elastase. A competitive inhibitor of SGMPII, L-Val-L-Trp, protects the enzyme against inactivation by ClCH2CO-DL-(N-OH)Leu-Ala-Gly-NH2 in a competitive manner. Furthermore, the pH profile of the inactivation closely resembles that for the hydrolysis of synthetic peptide substrates by the enzyme. These findings suggest that these reagents bind reversibly and react irreversibly at the active site of the enzyme. PMID:8056768

  20. Streptomyces griseus aminopeptidase is a calcium-activated zinc metalloprotein. Purification and properties of the enzyme.

    PubMed

    Spungin, A; Blumberg, S

    1989-08-01

    A heat-stable aminopeptidase with an N-terminal Ala-Pro-Asp-Ile-Pro-Leu sequence has been purified from Streptomyces griseus by heat treatment followed by gel-exclusion and anion-exchange chromatographic procedures. The enzyme is a monomeric zinc metalloenzyme showing an apparent molecular mass of 33 kDa by sodium dodecyl sulfate/polyacrylamide gel electrophoresis and 21 kDa by gel filtration on Superose 12. Calcium ions bind to the enzyme, pKCa 4.5, and activate it about sixfold when the substrate is leucine-4-nitroanilide (0.4 mM in 50 mM Tris/HCl pH 8.0, 25 degrees C). Binding of Ca2+ also contributes to the thermal stability of the protein. This aminopeptidase may be useful for two-stage assays of bacterial and mammalian metalloendopeptidases; it may also serve in studies of proteolytic enzyme activation by calcium ions. PMID:2503378

  1. Distribution of the Lyme Disease Spirochete Borrelia burgdorferi in Naturally and Experimentally Infected Western Gray Squirrels (Sciurus griseus)

    PubMed Central

    Jensen, Kelly; Salkeld, Daniel J.; Lane, Robert S.

    2010-01-01

    Abstract The dynamics of Borrelia burgdorferi infections within its natural hosts are poorly understood. We necropsied four wild-caught western gray squirrels (Sciurus griseus) that were acquired during a previous study that evaluated the reservoir competence of this rodent for the Lyme disease spirochete. One animal was infected experimentally, whereas the others were infected in the wild before capture. To investigate dissemination of B. burgdorferi and concurrent histopathologic lesions in different tissues, blood specimens, synovial and cerebrospinal fluid, ear-punch biopsies, and diverse tissue samples from skin and various organs were taken and examined by culture, polymerase chain reaction, and histology. Borrelia-positive cultures were obtained from three of the squirrels, that is, from skin biopsies (7 of 20 samples), ear-punch biopsies (2 of 8), and one (1 of 5) lymph node. Sequencing of amplicons confirmed B. burgdorferi sensu stricto (s.s.) infection in 9 of 10 culture-positive samples and in DNA extracted from all 10 positive cultures. The experimentally infected squirrel yielded most of the positive samples. In contrast, bodily fluids, all other organ specimens from these animals, and all samples from one naturally infected squirrel were negative for Borrelia for both assays. None of the necropsied squirrels exhibited specific clinical signs associated with B. burgdorferi. Similarly, necropsy and histological examination of tissues indicated the presence of underlying infectious processes, none of which could be ascribed conclusively to B. burgdorferi infection. Based on these results, obtained from a small number of animals investigated at a single time point, we suggest that B. burgdorferi s.s. infection in S. griseus may result in rather localized dissemination of spirochetes, and that mild or nonclinical disease might be more common after several months of infection duration. Since spirochetes could be detected in squirrels 7–21 months

  2. Unexpected Positive Buoyancy in Deep Sea Sharks, Hexanchus griseus, and a Echinorhinus cookei.

    PubMed

    Nakamura, Itsumi; Meyer, Carl G; Sato, Katsufumi

    2015-01-01

    We do not expect non air-breathing aquatic animals to exhibit positive buoyancy. Sharks, for example, rely on oil-filled livers instead of gas-filled swim bladders to increase their buoyancy, but are nonetheless ubiquitously regarded as either negatively or neutrally buoyant. Deep-sea sharks have particularly large, oil-filled livers, and are believed to be neutrally buoyant in their natural habitat, but this has never been confirmed. To empirically determine the buoyancy status of two species of deep-sea sharks (bluntnose sixgill sharks, Hexanchus griseus, and a prickly shark, Echinorhinus cookei) in their natural habitat, we used accelerometer-magnetometer data loggers to measure their swimming performance. Both species of deep-sea sharks showed similar diel vertical migrations: they swam at depths of 200-300 m at night and deeper than 500 m during the day. Ambient water temperature was around 15°C at 200-300 m but below 7°C at depths greater than 500 m. During vertical movements, all deep-sea sharks showed higher swimming efforts during descent than ascent to maintain a given swimming speed, and were able to glide uphill for extended periods (several minutes), indicating that these deep-sea sharks are in fact positively buoyant in their natural habitats. This positive buoyancy may adaptive for stealthy hunting (i.e. upward gliding to surprise prey from underneath) or may facilitate evening upward migrations when muscle temperatures are coolest, and swimming most sluggish, after spending the day in deep, cold water. Positive buoyancy could potentially be widespread in fish conducting daily vertical migration in deep-sea habitats. PMID:26061525

  3. Gender, season and management affect fecal glucocorticoid metabolite concentrations in captive goral (Naemorhedus griseus) in Thailand.

    PubMed

    Khonmee, Jaruwan; Brown, Janine L; Rojanasthien, Suvichai; Aunsusin, Anurut; Thumasanukul, Dissakul; Kongphoemphun, Adisorn; Siriaroonrat, Boripat; Tipkantha, Wanlaya; Punyapornwithaya, Veerasak; Thitaram, Chatchote

    2014-01-01

    Chinese goral (Naemorhedus griseus) are a threatened species in Thailand and the focus of captive breeding for possible reintroduction. However, little is known of their biology or what factors in the captive environment affect welfare. Our objective was to determine the impact of gender, season, and management on goral adrenal activity. We hypothesized that differences in fecal glucocorticoid concentrations would be related to animal density. Fecal samples were collected 3 days/week for 1 year from 63 individuals (n = 32 males, 31 females) at two facilities that house the majority of goral in Thailand: Omkoi Wildlife Sanctuary (Omkoi), an off-exhibit breeding center that houses goral in individual pens (16 pens; n = 8 males, 8 females) and in small family groups (8 pens; n = 8 males, 8 females); and the Chiang Mai Night Safari (NS), a zoo that maintains 31 goral (n = 17 males, 14 females) in one large pen. Glucocorticoid metabolite concentrations were higher in male than female goral at Omkoi throughout the year, and there was a seasonal effect on adrenal activity (p<0.05). Goral at Omkoi and NS were used to test the effect of animal density on fecal glucocorticoid excretion of goral housed in similar-sized enclosures. Overall, the highest levels were found at NS (n = 31 adults/pen; 27 m2 per animal) compared to Omkoi (n = 2 adults/pen; 400 m2 per animal) (p<0.05). Overall findings support our hypothesis that animal density and aspects of the captive environment impact adrenal steroid activity in captive goral. In addition, gender and season also had significant effects on glucocorticoid metabolite production. Potential stressors pertaining to the welfare of this species were identified, which will guide future efforts to improve management and create self-sustaining and healthy populations of this threatened species. PMID:24637886

  4. Gender, Season and Management Affect Fecal Glucocorticoid Metabolite Concentrations in Captive Goral (Naemorhedus griseus) in Thailand

    PubMed Central

    Khonmee, Jaruwan; Brown, Janine L.; Rojanasthien, Suvichai; Aunsusin, Anurut; Thumasanukul, Dissakul; Kongphoemphun, Adisorn; Siriaroonrat, Boripat; Tipkantha, Wanlaya; Punyapornwithaya, Veerasak; Thitaram, Chatchote

    2014-01-01

    Chinese goral (Naemorhedus griseus) are a threatened species in Thailand and the focus of captive breeding for possible reintroduction. However, little is known of their biology or what factors in the captive environment affect welfare. Our objective was to determine the impact of gender, season, and management on goral adrenal activity. We hypothesized that differences in fecal glucocorticoid concentrations would be related to animal density. Fecal samples were collected 3 days/week for 1 year from 63 individuals (n = 32 males, 31 females) at two facilities that house the majority of goral in Thailand: Omkoi Wildlife Sanctuary (Omkoi), an off-exhibit breeding center that houses goral in individual pens (16 pens; n = 8 males, 8 females) and in small family groups (8 pens; n = 8 males, 8 females); and the Chiang Mai Night Safari (NS), a zoo that maintains 31 goral (n = 17 males, 14 females) in one large pen. Glucocorticoid metabolite concentrations were higher in male than female goral at Omkoi throughout the year, and there was a seasonal effect on adrenal activity (p<0.05). Goral at Omkoi and NS were used to test the effect of animal density on fecal glucocorticoid excretion of goral housed in similar-sized enclosures. Overall, the highest levels were found at NS (n = 31 adults/pen; 27 m2 per animal) compared to Omkoi (n = 2 adults/pen; 400 m2 per animal) (p<0.05). Overall findings support our hypothesis that animal density and aspects of the captive environment impact adrenal steroid activity in captive goral. In addition, gender and season also had significant effects on glucocorticoid metabolite production. Potential stressors pertaining to the welfare of this species were identified, which will guide future efforts to improve management and create self-sustaining and healthy populations of this threatened species. PMID:24637886

  5. Unexpected Positive Buoyancy in Deep Sea Sharks, Hexanchus griseus, and a Echinorhinus cookei

    PubMed Central

    Nakamura, Itsumi; Meyer, Carl G.; Sato, Katsufumi

    2015-01-01

    We do not expect non air-breathing aquatic animals to exhibit positive buoyancy. Sharks, for example, rely on oil-filled livers instead of gas-filled swim bladders to increase their buoyancy, but are nonetheless ubiquitously regarded as either negatively or neutrally buoyant. Deep-sea sharks have particularly large, oil-filled livers, and are believed to be neutrally buoyant in their natural habitat, but this has never been confirmed. To empirically determine the buoyancy status of two species of deep-sea sharks (bluntnose sixgill sharks, Hexanchus griseus, and a prickly shark, Echinorhinus cookei) in their natural habitat, we used accelerometer-magnetometer data loggers to measure their swimming performance. Both species of deep-sea sharks showed similar diel vertical migrations: they swam at depths of 200–300 m at night and deeper than 500 m during the day. Ambient water temperature was around 15°C at 200–300 m but below 7°C at depths greater than 500 m. During vertical movements, all deep-sea sharks showed higher swimming efforts during descent than ascent to maintain a given swimming speed, and were able to glide uphill for extended periods (several minutes), indicating that these deep-sea sharks are in fact positively buoyant in their natural habitats. This positive buoyancy may adaptive for stealthy hunting (i.e. upward gliding to surprise prey from underneath) or may facilitate evening upward migrations when muscle temperatures are coolest, and swimming most sluggish, after spending the day in deep, cold water. Positive buoyancy could potentially be widespread in fish conducting daily vertical migration in deep-sea habitats. PMID:26061525

  6. Interaction of Streptomyces subtilisin inhibitor (SSI) with Streptomyces griseus metallo-endopeptidase II (SGMP II).

    PubMed

    Kumazaki, T; Kajiwara, K; Kojima, S; Miura, K; Ishii, S

    1993-10-01

    We have unexpectedly found that Streptomyces subtilisin inhibitor (SSI) and some other similar serine protease inhibitors produced by Streptomycetes strongly inhibit Streptomyces griseus metallo-endopeptidase II (SGMP II) [Kajiwara, K. et al. (1991) J. Biochem. 110, 350-354]. In order to elucidate the mode of their unusual interaction with SGMP II in more detail, we prepared twelve kinds of SSI analogues, in which one or two amino acid residues in the peptide segment from Thr64 to Val74 of wild-type SSI had been replaced or deleted by site-directed mutagenesis, and determined the dissociation constants of their complexes with SGMP II. Six analogues among them showed dissociation constants one order of magnitude lower than that of the wild type. Three had higher values. The results suggest that at least some residues in this segment are interacting with SGMP II in the complex. We also prepared an SSI mutant in which the disulfide bridge between Cys71 and Cys101 had been eliminated by replacing the two Cys residues with Ser residues. This mutated SSI inhibited SGMP II as strongly as the wild-type SSI did. While peptide bonds in the wild-type molecule did not suffer from the hydrolytic action of SGMP II except those at the amino-terminal fragile portion, the Pro72-Met73 bond of the mutant was specifically cleaved by the enzyme. This peptide bond, therefore, seems to play the role of the reactive site in the interaction of SSI with SGMP II. PMID:8276770

  7. A small lytic polysaccharide monooxygenase from Streptomyces griseus targeting α- and β-chitin.

    PubMed

    Nakagawa, Yuko S; Kudo, Madoka; Loose, Jennifer S M; Ishikawa, Takahiro; Totani, Kazuhide; Eijsink, Vincent G H; Vaaje-Kolstad, Gustav

    2015-03-01

    The lytic polysaccharide monooxygenases (LPMOs) have received considerable attention subsequent to their discovery because of their ability to boost the enzymatic conversion of recalcitrant polysaccharides. In the present study, we describe the enzymatic properties of SgLPMO10F, a small (15 kDa) auxilliary activity (AA) family 10 LPMO from Streptomyces griseus belonging to a clade of the phylogenetic tree without any characterized representative. The protein was expressed using a Brevibacillus-based expression system that had not been used previously for LPMO expression and that also ensures correct processing of the N-terminus crucial for LPMO activity. The enzyme was active towards both α- and β-chitin and showed stronger binding and a greater release of soluble oxidized products for the latter allomorph. In chitinase synergy assays, however, SgLPMO10F worked slightly better for α-chitin, increasing chitin solubilization yields by up to 30-fold and 20-fold for α- and β-chitin, respectively. Synergy experiments with various chitinases showed that the addition of SgLPMO10F leads to a substantial increase in the (GlcNAc)2 :GlcNAc product ratio, in reactions with α-chitin only. This underpins the structural differences between the substrates and also shows that, on α-chitin, SgLPMO10F affects the binding mode and/or degree of processivity of the chitinases tested. Variation in the only exposed aromatic residue in the substrate-binding surface of LPMO10s has previously been linked to preferential binding for α-chitin (exposed Trp) or β-chitin (exposed Tyr). Mutation of this residue, Tyr56, in SgLPMO10F to Trp had no detectable effect on substrate-binding preferences but, in synergy experiments, the mutant appeared to be more efficient on α-chitin. PMID:25605134

  8. Characterization of ssfR and ssgA, Two Genes Involved in Sporulation of Streptomyces griseus

    PubMed Central

    Jiang, Hao; Kendrick, Kathleen E.

    2000-01-01

    In the presence of cefoxitin, which inhibits septum formation during sporulation, Streptomyces griseus is unable to sporulate, retaining the sonication sensitivity of nonsporulating hyphae. Cefoxitin- and sonication-resistant mutant SKK2600 was isolated and showed many morphological differences from its parental strain. A 3.6-kb DNA fragment that complemented the mutations of SKK2600 contained two open reading frames (ORFs), either of which could complement SKK2600. One ORF, designated ssfR, encoded a protein containing a potential DNA-binding helix-turn-helix motif close to its N terminus. SsfR is similar to members of a large family of transcriptional regulators, particularly IclR of Escherichia coli. The second ORF was identified as ssgA, a previously described sporulation gene from S. griseus (S. Kawamoto and J. C. Ensign, Actinomycetology 9:136–151, 1995). A point mutation of C to T seven nucleotides upstream of the UGA stop codon of ssfR was responsible for the phenotype of isolated mutant strain SKK2600. Surprisingly, this mutation should not change the primary structure of SsfR. The ssfR and ssgA disruption mutants were constructed and showed the “white” mutant phenotype, with some growth medium dependence. In addition, the ssfR null mutant sporulated ectopically in phosphate starvation medium. PMID:10986257

  9. Effects of geolocation archival tags on reproduction and adult body mass of sooty shearwaters (Puffinus griseus)

    USGS Publications Warehouse

    Adams, J.; Scott, D.; McKechnie, S.; Blackwell, G.; Shaffer, S.A.; Moller, H.

    2009-01-01

    We attached 11 g (1.4% body-mass equivalent) global location sensing (GLS) archival tag packages to tarsi of 25 breeding sooty shearwaters (Puffinus griseus, titi) on Whenua Hou (Codfish Island), New Zealand during the chick-rearing period in 2005. Compared with chicks reared by non-handled adults that did not carry tags, deployment of tags on one or both adult parents ultimately resulted in 35% reduction in chick body mass and significantly reduced chick skeletal size preceding fledging (19 April). However, body mass between chick groups was not significantly different after controlling for skeletal size. Effects on chicks were more pronounced in six pairs where both parents carried tags. Chick mass was negatively related to the duration that adults carried tags. In this study, none of the chicks reared by pairs where both parents were tagged, 54% of chicks reared by pairs where one parent was tagged, and 83% of chicks reared by non-handled and non-tagged parents achieved a previously determined pre-fledging mass threshold (564 g; Sagar & Horning 1998). Body mass of adults carrying tags and returning from transequatorial migration the following year were 4% lighter on average than non-tagged birds, but this difference was not statistically significant. Reduced mass among chicks reared by adults carrying tags during the chick-provisioning period indicated that adults altered "normal" provisioning behaviours to maintain their own body condition at the expense of their chicks. Population-level information derived from telemetry studies can reveal important habitat-linked behaviours, unique aspects of seabird foraging behaviours, and migration ecology. Information for some species (e.g., overlap with fisheries) can aid conservation and marine ecosystem management. We advise caution, however, when interpreting certain data related to adult provisioning behaviours (e.g., time spent foraging, provisioning rates, etc.). If effects on individuals are of concern, we suggest

  10. Assessment of ovarian activity in captive goral (Naemorhedus griseus) using noninvasive fecal steroid monitoring.

    PubMed

    Khonmee, Jaruwan; Brown, Janine L; Taya, Kazuyoshi; Rojanasthien, Suvichai; Punyapornwithaya, Veerasak; Thumasanukul, Dissakul; Kongphoemphun, Adisorn; Siriaroonrat, Boripat; Tipkantha, Wanlaya; Pongpiachan, Petai; Thitaram, Chatchote

    2014-10-15

    To date, there is no information on gonadal steroidogenic activity of female goral (Naemorhedus griseus), a threatened species of Thailand. Captive goral populations have been established to produce animals for ex situ conservation and reintroduction, but as yet none are self-sustaining. The objectives of the present study were to (1) determine the influence of season on ovarian steriodogenic function; and (2) examine the relationship between gonadal hormone excretion and sexual behaviors throughout the year. Fecal samples were collected 5 to 7 days/wk for 15 months from 8 adult females housed at Omkoi Wildlife Breeding Center in Thailand and analyzed for ovarian steroid metabolites using validated enzyme immunoassays. Observations of sexual behaviors and mating were conducted each morning for 30 min/session. Based on fecal estrogen and progestagen metabolite concentrations, the overall estrous cycle length was about 21 days, with a 2- to 3-day follicular phase and an 18- to 20-day luteal phase. Sexual behaviors, most notably tail-up, increased for 2 to 3 days during the time estrogens were elevated during mating. Fecal progestagens were elevated during luteal phases and increased further during gestation, which lasted approximately 7 months. The lactation period was 5 months, and females were anestrus for 2 to 5 of those months, with the exception of one that cycled continuously throughout. Two females conceived around 2 months postpartum and so were pregnant during lactation. Birth records over the past 21 years indicated young are born throughout the year. This combined with the hormonal data suggests that female gorals are not strongly seasonal, at least in captivity, although there was considerable variation among females in estrogen and progestagen patterns. In conclusion, fecal steroid metabolite monitoring is an effective means of assessing ovarian function in this species and will be a useful tool for breeding management and planned development of

  11. Epidemiological studies on intestinal helminth parasites of the patagonian grey fox (Pseudalopex griseus) in Tierra del Fuego, Patagonia Argentina.

    PubMed

    Zanini, Fabián; Laferrara, Miguel; Bitsch, Matías; Pérez, Héctor; Elissondo, Maria Celina

    2006-03-31

    The present work was performed to study the intestinal helminths of the patagonian grey fox (Pseudalopex griseus) and to obtain information about its possible role in the sylvatic life cycle of Echinococcu granulosus in Tierra del Fuego, Patagonia Argentina. Eighty-one foxes were captured and subject to post-mortem analysis. Thirty-one foxes (38.3%) harboured helminths. A total of six helminth species were recovered. Only one adult of E. granulosus was found in the studied samples. The current study is the first report of the intestinal helminths of the patagonian grey fox in Tierra del Fuego, Argentina and showed that this specie is probably not an important reservoir host for E. granulosus. PMID:16414190

  12. CebR as a master regulator for cellulose/cellooligosaccharide catabolism affects morphological development in Streptomyces griseus.

    PubMed

    Marushima, Kazuya; Ohnishi, Yasuo; Horinouchi, Sueharu

    2009-10-01

    Streptomyces griseus mutants exhibiting deficient glucose repression of beta-galactosidase activity on lactose-containing minimal medium supplemented with a high concentration of glucose were isolated. One of these mutants had a 12-bp deletion in cebR, which encodes a LacI/GalR family regulator. Disruption of cebR in the wild-type strain caused the same phenotype as the mutant, indicating that CebR is required for glucose repression of beta-galactosidase activity. Recombinant CebR protein bound to a 14-bp inverted-repeat sequence (designated the CebR box) present in the promoter regions of cebR and the putative cellobiose utilization operon, cebEFG-bglC. The DNA-binding activity of CebR was impaired by cellooligosaccharides, including cellobiose, cellotriose, cellotetraose, cellopentaose, and cellohexaose. In agreement with this observation, transcription from the cebE and cebR promoters was greatly enhanced by the addition of cellobiose to the medium. Seven other genes containing one or two CebR boxes in their upstream regions were found in the S. griseus genome. Five of these genes encode putative secreted proteins: two cellulases, a cellulose-binding protein, a pectate lyase, and a protein of unknown function. These five genes and cebEFG-bglC were transcribed at levels 4 to 130 times higher in the DeltacebR mutant than in the wild-type strain, as determined by quantitative reverse transcription-PCR. These findings indicate that CebR is a master regulator of cellulose/cellooligosaccharide catabolism. Unexpectedly, the DeltacebR mutant formed very few aerial hyphae on lactose-containing medium, demonstrating a link between carbon source utilization and morphological development. PMID:19648249

  13. Biosynthesis of the antitumor chromomycin A3 in Streptomyces griseus: analysis of the gene cluster and rational design of novel chromomycin analogs.

    PubMed

    Menéndez, Nuria; Nur-e-Alam, Mohammad; Braña, Alfredo F; Rohr, Jürgen; Salas, José A; Méndez, Carmen

    2004-01-01

    The biosynthetic gene cluster of the aureolic acid type antitumor drug chromomycin A3 from S. griseus subsp. griseus has been identified and characterized. It spans 43 kb and contains 36 genes involved in polyketide biosynthesis and modification, deoxysugar biosynthesis and sugar transfer, pathway regulation and resistance. The organization of the cluster clearly differs from that of the closely related mithramycin. Involvement of the cluster in chromomycin A3 biosynthesis was demonstrated by disrupting the cmmWI gene encoding a polyketide reductase involved in side chain reduction. Three novel chromomycin derivatives were obtained, named chromomycin SK, chromomycin SA, and chromomycin SDK, which show antitumor activity and differ with respect to their 3-side chains. A pathway for the biosynthesis of chromomycin A3 and its deoxysugars is proposed. PMID:15112992

  14. Copper Levels in Tissues of Dolphins Tursiops truncatus, Stenella coeruleoalba and Grampus griseus from the Croatian Adriatic Coast.

    PubMed

    Bilandžić, Nina; Đokić, Maja; Sedak, Marija; Đuras, Martina; Gomerčić, Tomislav; Benić, Miroslav

    2016-09-01

    Copper concentrations were determined in muscle, liver, kidney, spleen and lung tissues of three dolphin species. Dolphins of Tursiops truncatus (young and adult), Stenella coeruleoalba and Grampus griseus were stranded along the Croatian coast. Concentrations in tissues of all three dolphin species were highest in the liver (4.92-16.5 μg/g) followed by kidney (2.85-5.29 μg/g). Similar levels were measured in muscle, spleen and lung in range 1.13-3.67 μg/g. Statistics analysis showed significant differences of Cu concentrations for muscle (p = 0.008), kidney (p = 0.04) and liver (p = 0.02) between the three dolphin species. Also, for all three species significant differences between tissue types of the same species were determined (p < 0.001, all). However, there were no significant differences in Cu levels of the same tissues between males and females within same species. Also, significant differences of body length and weight between three dolphin were found (p < 0.001, both). PMID:27246724

  15. Intracellular distribution of estradiol and estrogen binding sites in the uterus and oviducts of the green monkey (cercopithecus griseus)

    SciTech Connect

    Alekseeva, M.L.; Fanchenko, N.D.; Novikov, E.A.; Shchedrina, R.N.

    1986-03-01

    This paper describes a comparative investigation of changes in estradoil (E/sub 2/) and progesterone (P) concentrations in the blood plasma and concentrations of E/sub 2/ and estrogen binding sites (EBS) in the uterus and oviducts of C. griseus in the course of the menstrual cycle. A 0.25 aqueous solution of sucrose, 10mM Tris-HC1 buffer containing 1.5 mM EDTA, a 0.1M phosphate buffer containing 0.01% and 0.1% gelatin, antisera against E/sub 2/-17beta and P, labeled 3 /SUB H/ -E/sub 2/-17beta and /sup 3/H-P (specific radioactivity 104 and 96 Ci/nmole respectively), and their unlabeled analogs, 0.5, 1, and 5% suspensions of activated charcoal in buffer with the addition of 0.1% gelatin, and scintillation fluid consisting of 0.5% PPO and 0.05% POPOP in toluene were used. Indirect evidence shows the absence of any additional intracellular mechanisms affecting translocation of activated cytoplasmic estrogenreceptor complexes into the nucleus.

  16. First isolation of Leptospira interrogans from Lycalopex griseus (South American gray fox) in Argentina shows new MLVA genotype.

    PubMed

    Scialfa, Exequiel; Brihuega, Bibiana; Venzano, Agustín; Morris, Winston Eduardo; Bolpe, Jorge; Schettino, Mateo

    2013-01-01

    To identify carriers of Leptospira spp. in Argentina, wild animals were trapped in Buenos Aires Province during three nights, capturing 12 Didelphis albiventris (white-eared opossum), six Chaetophractus villosus (big hairy armadillo), five Lycalopex griseus (South American gray fox), and two Conepatus chinga (Molina's hog-nosed skunk). All were tested by microscopic agglutination test, and five (two gray foxes, two armadillos, and one skunk) were positive for Leptospira interrogans serovars Canicola and Icterohaemorrhagiae, L. borgpetersenii serovar Castellonis, and L. kirschneri serovar Grippotyphosa, at titers of 1:50 and 1:100. Kidney tissue from all animals was cultured, and one isolate of L. interrogans from a gray fox was obtained. Hamsters inoculated with the isolate died after 6 days with no macroscopic lesions at necropsy. However, histologic examination revealed glomerulonephritis, interstitial nephritis, and pneumonia. The Leptospira strain from the South American gray fox was analyzed serologically and its pathogenicity was established. Genotyping through multiple-locus variable-number tandem repeat analysis showed that the strain was a new genotype related to the L. interrogans serogroup Icterohaemorrhagiae. PMID:23307384

  17. Observations on Abundance of Bluntnose Sixgill Sharks, Hexanchus griseus, in an Urban Waterway in Puget Sound, 2003-2005

    PubMed Central

    Griffing, Denise; Larson, Shawn; Hollander, Joel; Carpenter, Tim; Christiansen, Jeff; Doss, Charles

    2014-01-01

    The bluntnose sixgill shark, Hexanchus griseus, is a widely distributed but poorly understood large, apex predator. Anecdotal reports of diver-shark encounters in the late 1990’s and early 2000’s in the Pacific Northwest stimulated interest in the normally deep-dwelling shark and its presence in the shallow waters of Puget Sound. Analysis of underwater video documenting sharks at the Seattle Aquarium’s sixgill research site in Elliott Bay and mark-resight techniques were used to answer research questions about abundance and seasonality. Seasonal changes in relative abundance in Puget Sound from 2003–2005 are reported here. At the Seattle Aquarium study site, 45 sixgills were tagged with modified Floy visual marker tags, along with an estimated 197 observations of untagged sharks plus 31 returning tagged sharks, for a total of 273 sixgill observations recorded. A mark-resight statistical model based on analysis of underwater video estimated a range of abundance from a high of 98 sharks seen in July of 2004 to a low of 32 sharks seen in March of 2004. Both analyses found sixgills significantly more abundant in the summer months at the Seattle Aquarium’s research station. PMID:24475229

  18. [Effect of preservation conditions on the viability and activity of Streptomyces griseus--producer of the antibiotic grizin].

    PubMed

    Trenina, G A; Lavrova, L N; Iustratova, L S; Kuklin, V V

    1983-03-01

    Strain AURIGenetics- 1552 of Str. griseus producing grisin used as a feed additive was obtained in the course of stepped selection. It is deposited at the Central Collection of Industrial Microorganisms of the USSR and designated as strain S-248. The strain was stored under varying conditions and their effect on its viability, morphological variation and antibiotic potency was studied. Investigation of the strain variation with respect to the cultural and morphological properties and the antibiotic production revealed definite correlation between the morphological properties of the culture and its capacity for the synthesis of the antibiotic. The medium G-1 containing KNO3 as the only source of nitrogen was found to be advantageous for maintaining the strain potency on storage with the method of subcultures or under a layer of mineral oil. It was shown that the strain can be successfully stored by lyophilization. This method in combination with selection of active variants from populations of lyophilized cells provided not only maintenance of the culture potency at the required level but also its increase. PMID:6407387

  19. Purification and characterization of an acidic amino acid specific endopeptidase of Streptomyces griseus obtained from a commercial preparation (Pronase).

    PubMed

    Yoshida, N; Tsuruyama, S; Nagata, K; Hirayama, K; Noda, K; Makisumi, S

    1988-09-01

    A protease was purified 163-fold from Pronase, a commercial product from culture filtrate of Streptomyces griseus, by a series of column chromatographies on CM-Toyopearl (Fractogel), Sephadex G-50, hydroxyapatite, and Z-Gly-D-Phe-AH-Sepharose 4B using Boc-Ala-Ala-Pro-Glu-pNA as a substrate. The final preparation was homogeneous by polyacrylamide gel electrophoresis (PAGE), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and gel isoelectric focusing. Studies on the substrate specificity with peptide p-nitroanilides revealed that this protease preferentially hydrolyzed peptide bonds on the carbonyl-terminal side of either glutamic acid or aspartic acid. It was most active at pH 8.8 for the hydrolysis of Boc-Ala-Ala-Pro-Glu-pNA. The molecular weight of the protease was estimated to be 20,000 by gel filtration on Sepharose 6B using 6 M guanidine hydrochloride as an eluent, and 22,000 by SDS-PAGE in the presence of 2-mercaptoethanol. The isoelectric point of the enzyme was 8.4. The enzyme was inactivated by diisopropyl phosphofluoridate (DFP) but not by p-chloromercuribenzoate (PCMB) or EDTA. PMID:3149277

  20. Severe glomerular disease in juvenile grey snapper Lutjanus griseus L. in the Gulf of Mexico caused by the myxozoan Sphaerospora motemarini n. sp.

    PubMed Central

    Holzer, Astrid S.; Pecková, Hanka; Patra, Sneha; Brennan, Nathan P.; Yanes-Roca, Carlos; Main, Kevan L.

    2013-01-01

    In the eastern Gulf of Mexico, off the coast of Florida, grey snapper, Lutjanus griseus was found to be infected with the myxozoan parasite Sphaerospora motemarini n. sp., with high prevalence (83%) and intensity of infection occuring in age-0 fish, and with parasite levels decreasing with age (age-1 snapper 40%; age-2 snapper 0%). The morphological, molecular and phylogenetic characterisation of the myxozoan showed that it is a member of the typically marine, polysporoplasmid Sphaerospora spp. which form a subclade within the Sphaerospora sensu stricto clade of myxozoans, which is characterised by large expansion segments in their SSU rDNA sequences. Presporogonic stages of S. motemarini n. sp. were detected in the blood, using PCR. Pseudoplasmodia and spores were found to develop in the renal corpuscles of the host, causing their massive expansion. Macroscopic and histopathological changes were observed in age-0 fish and show that S. motemarini n. sp. causes severe glomerulonephritis in L. griseus leading to a compromised host condition, which makes it more susceptible to stress (catch-and-release, predators, water quality) and can result in mortalities. These results are discussed in relation to the exploitation of grey snapper populations by commercial and recreational fisheries and with the observed increased mortalities with temperature along the coast of Florida. In the future, we would like to determine prevalence and intensity of infection with S. motemarini n. sp. in juvenile L. griseus in different areas of the Gulf of Mexico in order to be able to estimate the temperature dependence of S. motemarini n. sp. proliferation and to be able to predict its distribution and severity during climatic changes in the Gulf. PMID:24533325

  1. Affinity chromatography of trypsin and related enzymes. III. Purification of Streptomyces griseus trypsin using an affinity adsorbent containing a tryptic digest of protamine as a ligand.

    PubMed

    Yokosawa, H; Hanba, T; Ishii, S

    1976-04-01

    A new, simple method has been developed for the purification of Streptomyces griseus trypsin [EC 3.4.21.4] from Pronase. Only a single operation of affinity chromatography on an agarose derivative, which was easily prepared by coupling a tryptic digest of salmine to cyanogen bromide-activated Sepharose 4B, was required. A high degree of homogeneity was demonstrated for the purified enzyme by disc electrophoresis, SDS-polyacrylamide gel electrophoresis and gel filtration, as well as by active-site titration. The behavior of a carboxypeptides B [EC 3.4.12.3]-like enzyme present in Pronase is also discussed. PMID:819428

  2. Seasonal Sexual Segregation by Monomorphic Sooty Shearwaters Puffinus griseus Reflects Different Reproductive Roles during the Pre-Laying Period

    PubMed Central

    Hedd, April; Montevecchi, William A.; Phillips, Richard A.; Fifield, David A.

    2014-01-01

    Tracking technology has revolutionized knowledge of seabird movements; yet, few studies have examined sex differences in distribution and behavior of small to medium-sized, sexually-monomorphic seabirds. Application of bird-borne geolocation-immersion loggers revealed seasonal segregation in the sexually-monomorphic Sooty Shearwater Puffinus griseus, mainly in the pre-laying period, when there were clear differences in reproductive roles. Shearwaters first returned to the Falkland Islands on 27 Sept±8 d; males, on average, 8 d earlier than females. Prior to egg-laying, distribution at sea, colony attendance and behaviour depended on sex. Males foraged locally over the southern Patagonian Shelf and Burdwood Bank, spending mainly single days at sea and intervening nights in the burrow. Females, who flew for more of the day during this time, foraged in more distant areas of the northern Patagonian Shelf and Argentine Basin that were deeper, warmer and relatively more productive. Attendance of females at the colony was also more variable than that of males and, overall, males were present for significantly more of the pre-laying period (38 vs. 19% of time). Sex differences were reduced following egg-laying, with males and females using similar foraging areas and making trips of similar mean duration in incubation (7.6±2.7 d) and chick-rearing (1.4±1.3 d). Congruence continued into the non-breeding period, with both sexes showing similar patterns of activity and areas of occupancy in the NW Atlantic. Thus, seasonal changes in reproductive roles influenced patterns of sexual segregation; this occurred only early in the season, when male Sooty Shearwaters foraged locally, returning regularly to the colony to defend (or maintain) the burrow or the mate, while females concentrated on building resources for egg development in distant and relatively more productive waters. PMID:24416429

  3. Pathologic findings in Western gray squirrels (Sciurus griseus) from a notoedric mange epidemic in the San Bernardino Mountains, California.

    PubMed

    Stephenson, Nicole; Swift, Pam; Villepique, Jeffrey T; Clifford, Deana L; Nyaoke, Akinyi; De la Mora, Alfonso; Moore, Janet; Foley, Janet

    2013-12-01

    Notoedric mange, caused by the contagious, burrowing mite Notoedres centrifera, has been associated with several large-scale population declines of western gray squirrels (Sciurus griseus) and has been a significant obstacle to population recovery in Washington State where the species is listed as threatened. In 2009, residents and wildlife rehabilitators in the isolated San Bernardino Mountains of southern California reported a dramatic die-off of western gray squirrels, in what had been a previously dense and robust population. Individuals were observed suffering from abnormal neurologic behaviors (ataxia and obtundation) and severe skin disease. Full necropsy of five squirrels from the epidemic showed that all had moderate to severe infestation with mange mites and severe dermatitis characterized by hyperkeratosis, acanthosis, intralesional mites, intracorneal pustules and superficial bacteria. Mites from affected squirrels were evaluated by light and electron microscopy and identified as N. centrifera based on morphologic criteria. Additionally, the internal transcribed spacer-2 region of the mite was cloned, sequenced and accessioned in GenBank. The cause for the abnormal neurologic behavior was not confirmed on post-mortem examination. However, we hypothesize that mange can cause incoordination and obtundation as a result of malnutrition and dehydration, and intense pruritis may induce abnormal or erratic behavior that could be mistaken for neurologic signs. While we have characterized the severe impact this disease can have on individual animals, more work is needed to understand the impact on squirrel populations, particularly in view of the anecdotal reports of dramatic population declines that may take decades to recover. PMID:24533345

  4. Pathologic findings in Western gray squirrels (Sciurus griseus) from a notoedric mange epidemic in the San Bernardino Mountains, California☆

    PubMed Central

    Stephenson, Nicole; Swift, Pam; Villepique, Jeffrey T.; Clifford, Deana L.; Nyaoke, Akinyi; De la Mora, Alfonso; Moore, Janet; Foley, Janet

    2013-01-01

    Notoedric mange, caused by the contagious, burrowing mite Notoedres centrifera, has been associated with several large-scale population declines of western gray squirrels (Sciurus griseus) and has been a significant obstacle to population recovery in Washington State where the species is listed as threatened. In 2009, residents and wildlife rehabilitators in the isolated San Bernardino Mountains of southern California reported a dramatic die-off of western gray squirrels, in what had been a previously dense and robust population. Individuals were observed suffering from abnormal neurologic behaviors (ataxia and obtundation) and severe skin disease. Full necropsy of five squirrels from the epidemic showed that all had moderate to severe infestation with mange mites and severe dermatitis characterized by hyperkeratosis, acanthosis, intralesional mites, intracorneal pustules and superficial bacteria. Mites from affected squirrels were evaluated by light and electron microscopy and identified as N. centrifera based on morphologic criteria. Additionally, the internal transcribed spacer-2 region of the mite was cloned, sequenced and accessioned in GenBank. The cause for the abnormal neurologic behavior was not confirmed on post-mortem examination. However, we hypothesize that mange can cause incoordination and obtundation as a result of malnutrition and dehydration, and intense pruritis may induce abnormal or erratic behavior that could be mistaken for neurologic signs. While we have characterized the severe impact this disease can have on individual animals, more work is needed to understand the impact on squirrel populations, particularly in view of the anecdotal reports of dramatic population declines that may take decades to recover. PMID:24533345

  5. Characterization of FdmV as an Amide Synthetase for Fredericamycin A Biosynthesis in Streptomyces griseus ATCC 43944*

    PubMed Central

    Chen, Yihua; Wendt-Pienkowski, Evelyn; Ju, Jianhua; Lin, Shuangjun; Rajski, Scott R.; Shen, Ben

    2010-01-01

    Fredericamycin (FDM) A is a pentadecaketide natural product that features an amide linkage. Analysis of the fdm cluster from Streptomyces griseus ATCC 43944, however, failed to reveal genes encoding the types of amide synthetases commonly seen in natural product biosynthesis. Here, we report in vivo and in vitro characterizations of FdmV, an asparagine synthetase (AS) B-like protein, as an amide synthetase that catalyzes the amide bond formation in FDM A biosynthesis. This is supported by the findings that (i) inactivation of fdmV in vivo afforded the ΔfdmV mutant strain SB4027 that abolished FDM A and FDM E production but accumulated FDM C, a biosynthetic intermediate devoid of the characteristic amide linkage; (ii) FdmV in vitro catalyzes conversion of FDM C to FDM B, a known intermediate for FDM A biosynthesis (apparent Km = 162 ± 67 μm and kcat = 0.11 ± 0.02 min−1); and (iii) FdmV also catalyzes the amidation of FDM M-3, a structural analog of FDM C, to afford amide FDM M-6 in vitro, albeit at significantly reduced efficiency. Preliminary enzymatic studies revealed that, in addition to the common nitrogen sources (l-Gln and free amine) of class II glutamine amidotransferases (to which AS B belongs), FdmV can also utilize l-Asn as a nitrogen donor. The amide bond formation in FDM A biosynthesis is proposed to occur after C-8 hydroxylation but before the carbaspirocycle formation. PMID:20926388

  6. Substrate Recognition Mechanism and Substrate-Dependent Conformational Changes of an ROK Family Glucokinase from Streptomyces griseus

    PubMed Central

    Miyazono, Ken-ichi; Tabei, Nobumitsu; Morita, Sho; Ohnishi, Yasuo; Horinouchi, Sueharu

    2012-01-01

    Carbon catabolite repression (CCR) is a widespread phenomenon in many bacteria that is defined as the repression of catabolic enzyme activities for an unfavorable carbon source by the presence of a preferable carbon source. In Streptomyces, secondary metabolite production often is negatively affected by the carbon source, indicating the involvement of CCR in secondary metabolism. Although the CCR mechanism in Streptomyces still is unclear, glucokinase is presumably a central player in CCR. SgGlkA, a glucokinase from S. griseus, belongs to the ROK family glucokinases, which have two consensus sequence motifs (1 and 2). Here, we report the crystal structures of apo-SgGlkA, SgGlkA in complex with glucose, and SgGlkA in complex with glucose and adenylyl imidodiphosphate (AMPPNP), which are the first structures of an ROK family glucokinase. SgGlkA is divided into a small α/β domain and a large α+β domain, and it forms a dimer-of-dimer tetrameric configuration. SgGlkA binds a β-anomer of glucose between the two domains, and His157 in consensus sequence 1 plays an important role in the glucose-binding mechanism and anomer specificity of SgGlkA. In the structures of SgGlkA, His157 forms an HC3-type zinc finger motif with three cysteine residues in consensus sequence 2 to bind a zinc ion, and it forms two hydrogen bonds with the C1 and C2 hydroxyls of glucose. When the three structures are compared, the structure of SgGlkA is found to be modified by the binding of substrates. The substrate-dependent conformational changes of SgGlkA may be related to the CCR mechanism in Streptomyces. PMID:22101842

  7. Seasonal sexual segregation by monomorphic Sooty Shearwaters Puffinus griseus reflects different reproductive roles during the pre-laying period.

    PubMed

    Hedd, April; Montevecchi, William A; Phillips, Richard A; Fifield, David A

    2014-01-01

    Tracking technology has revolutionized knowledge of seabird movements; yet, few studies have examined sex differences in distribution and behavior of small to medium-sized, sexually-monomorphic seabirds. Application of bird-borne geolocation-immersion loggers revealed seasonal segregation in the sexually-monomorphic Sooty Shearwater Puffinus griseus, mainly in the pre-laying period, when there were clear differences in reproductive roles. Shearwaters first returned to the Falkland Islands on 27 Sept±8 d; males, on average, 8 d earlier than females. Prior to egg-laying, distribution at sea, colony attendance and behaviour depended on sex. Males foraged locally over the southern Patagonian Shelf and Burdwood Bank, spending mainly single days at sea and intervening nights in the burrow. Females, who flew for more of the day during this time, foraged in more distant areas of the northern Patagonian Shelf and Argentine Basin that were deeper, warmer and relatively more productive. Attendance of females at the colony was also more variable than that of males and, overall, males were present for significantly more of the pre-laying period (38 vs. 19% of time). Sex differences were reduced following egg-laying, with males and females using similar foraging areas and making trips of similar mean duration in incubation (7.6±2.7 d) and chick-rearing (1.4±1.3 d). Congruence continued into the non-breeding period, with both sexes showing similar patterns of activity and areas of occupancy in the NW Atlantic. Thus, seasonal changes in reproductive roles influenced patterns of sexual segregation; this occurred only early in the season, when male Sooty Shearwaters foraged locally, returning regularly to the colony to defend (or maintain) the burrow or the mate, while females concentrated on building resources for egg development in distant and relatively more productive waters. PMID:24416429

  8. Control by A-Factor of a Metalloendopeptidase Gene Involved in Aerial Mycelium Formation in Streptomyces griseus

    PubMed Central

    Kato, Jun-ya; Suzuki, Ayano; Yamazaki, Haruka; Ohnishi, Yasuo; Horinouchi, Sueharu

    2002-01-01

    In Streptomyces griseus, A-factor (2-isocapryloyl-3R-hydroxymethyl-γ-butyrolactone) switches on aerial mycelium formation and secondary metabolite biosynthesis. An A-factor-dependent transcriptional activator, AdpA, activates multiple genes required for morphological development and secondary metabolism in a programmed manner. A region upstream of a zinc-containing metalloendopeptidase gene (sgmA) was found among the DNA fragments that had been isolated as AdpA-binding sites. The primary product of sgmA consisted of N-terminal pre, N-terminal pro, mature, and C-terminal pro regions. sgmA was transcribed in an AdpA-dependent manner, and its transcription was markedly enhanced at the timing of aerial mycelium formation. AdpA bound two sites in the region upstream of the sgmA promoter; one was at about nucleotide position −60 (A site) with respect to the transcriptional start point of sgmA, and the other was at about position −260 (B site), as determined by DNase I footprinting. Transcriptional analysis with mutated promoters showed that the A site was essential for the switching on of sgmA transcription and that the B site was necessary for the marked enhancement of transcription at the timing of aerial mycelium formation. Disruption of the chromosomal sgmA gene resulted in a delay in aerial hypha formation by half a day. SgmA is therefore suggested to be associated with the programmed morphological development of Streptomyces, in which this peptidase, perhaps together with other hydrolytic enzymes, plays a role in the degradation of proteins in substrate hyphae for reuse in aerial hypha formation. PMID:12374836

  9. Control by A-factor of a metalloendopeptidase gene involved in aerial mycelium formation in Streptomyces griseus.

    PubMed

    Kato, Jun-ya; Suzuki, Ayano; Yamazaki, Haruka; Ohnishi, Yasuo; Horinouchi, Sueharu

    2002-11-01

    In Streptomyces griseus, A-factor (2-isocapryloyl-3R-hydroxymethyl-gamma-butyrolactone) switches on aerial mycelium formation and secondary metabolite biosynthesis. An A-factor-dependent transcriptional activator, AdpA, activates multiple genes required for morphological development and secondary metabolism in a programmed manner. A region upstream of a zinc-containing metalloendopeptidase gene (sgmA) was found among the DNA fragments that had been isolated as AdpA-binding sites. The primary product of sgmA consisted of N-terminal pre, N-terminal pro, mature, and C-terminal pro regions. sgmA was transcribed in an AdpA-dependent manner, and its transcription was markedly enhanced at the timing of aerial mycelium formation. AdpA bound two sites in the region upstream of the sgmA promoter; one was at about nucleotide position -60 (A site) with respect to the transcriptional start point of sgmA, and the other was at about position -260 (B site), as determined by DNase I footprinting. Transcriptional analysis with mutated promoters showed that the A site was essential for the switching on of sgmA transcription and that the B site was necessary for the marked enhancement of transcription at the timing of aerial mycelium formation. Disruption of the chromosomal sgmA gene resulted in a delay in aerial hypha formation by half a day. SgmA is therefore suggested to be associated with the programmed morphological development of Streptomyces, in which this peptidase, perhaps together with other hydrolytic enzymes, plays a role in the degradation of proteins in substrate hyphae for reuse in aerial hypha formation. PMID:12374836

  10. l-Asparaginase from Streptomyces griseus NIOT-VKMA29: optimization of process variables using factorial designs and molecular characterization of l-asparaginase gene

    PubMed Central

    Meena, Balakrishnan; Anburajan, Lawrance; Sathish, Thadikamala; Vijaya Raghavan, Rangamaran; Dharani, Gopal; Valsalan Vinithkumar, Nambali; Kirubagaran, Ramalingam

    2015-01-01

    Marine actinobacteria are known to be a rich source for novel metabolites with diverse biological activities. In this study, a potential extracellular L-asparaginase was characterised from the Streptomyces griseus NIOT-VKMA29. Box-Behnken based optimization was used to determine the culture medium components to enhance the L-asparaginase production. pH, starch, yeast extract and L-asparagine has a direct correlation for enzyme production with a maximum yield of 56.78 IU mL−1. A verification experiment was performed to validate the experiment and more than 99% validity was established. L-Asparaginase biosynthesis gene (ansA) from Streptomyces griseus NIOT-VKMA29 was heterologously expressed in Escherichia coli M15 and the enzyme production was increased threefold (123 IU mL−1) over the native strain. The ansA gene sequences reported in this study encloses several base substitutions with that of reported sequences in GenBank, resulting in altered amino acid sequences of the translated protein. PMID:26206135

  11. Karyotype morphology suggests that the Nyctibius griseus (Gmelin, 1789) carries an ancestral ZW-chromosome pair to the order Caprimulgiformes (Aves).

    PubMed

    Nieto, Leonardo Martin; Kretschmer, Rafael; Ledesma, Mario Angel; Garnero, Analía Del Valle; Gunski, Ricardo José

    2012-01-01

    Studies of karyotypes have been revealing important information on the taxonomic relationships and evolutionary patterns in various groups of birds. However, the order Caprimulgiformes is one of the least known in terms of its cytotaxonomy. So far, there are no cytogenetic data in the literature on birds belonging to 3 of 5 families of this order -Nyctibiidae, Steatornithidae and Aegothelidae. For this reason, the aim of our study was to describe the karyotype of Nyctibius griseus (Gmelin, 1789) (Aves, Nyctibiidae, Caprimulgiformes) and contribute with new data that could help to clarify the evolutionary relationships in this group. Bone marrow was cultured directly to obtain material for the chromosome study. C-banding was used to visualize the constitutive heterochromatin and Ag-NOR-banding to reveal nucleolus organizer regions. The diploid number observed was 2n=86±. Using sequential Giemsa/C-banding staining, we determined that the W chromosome was entirely C-band positive with the two most prominent markers in the interstitial and distal regions of the long arm. The nucleolus organizer regions showed a typical location in a pair of microchromosomes that exhibited Ag-NOR.The results obtained for Nyctibius griseus suggest that, of all the species studied in the references cited, it has the most ancestral sex chromosome composition of the order Caprimulgiformes. PMID:24260678

  12. Coinfection of western gray squirrel (Sciurus griseus) and other sciurid rodents with Borrelia burgdorferi sensu stricto and Anaplasma phagocytophilum in California.

    PubMed

    Nieto, Nathan C; Leonhard, Sarah; Foley, Janet E; Lane, Robert S

    2010-01-01

    Overlapping geographic distributions of tick-borne disease agents utilizing the same tick vectors are common, and coinfection of humans, domestic animals, wildlife, and ticks with both Borrelia burgdorferi and Anaplasma phagocytophilum has been frequently reported. This study was undertaken in order to evaluate the prevalence of both B. burgdorferi sensu stricto (hereinafter referred to as B. burgdorferi) and A. phagocytophilum in several species of sciurid rodents from northern California, USA. Rodents were either collected dead as road-kills or live-trapped in four state parks from 13 counties. Thirty-seven western gray squirrels (Sciurus griseus), nine nonnative eastern gray squirrels (S. carolinensis) and an eastern fox squirrel (S. niger), four Douglas squirrels (Tamiasciurus douglasii), and two northern flying squirrels (Glaucomys sabrinus) were tested by polymerase chain reaction (PCR) and serology for evidence of coinfection. Of the 14 individual S. griseus that were PCR-positive for B. burgdorferi, two (14%) also were PCR-positive for A. phagocytophilum and 11 (79%) had serologic evidence of A. phagocytophilum exposure. Two of the four Douglas squirrels were PCR positive for B. burgdorferi and seropositive to A. phagocytophilum. Evidence of coinfection with these zoonotic pathogens in western gray squirrels suggests that both bacteria may be maintained in a similar transmission cycle involving this sciurid and the western black-legged tick Ixodes pacificus, the primary bridging vector to humans in the far-western US. PMID:20090047

  13. L-Asparaginase from Streptomyces griseus NIOT-VKMA29: optimization of process variables using factorial designs and molecular characterization of L-asparaginase gene

    NASA Astrophysics Data System (ADS)

    Meena, Balakrishnan; Anburajan, Lawrance; Sathish, Thadikamala; Vijaya Raghavan, Rangamaran; Dharani, Gopal; Valsalan Vinithkumar, Nambali; Kirubagaran, Ramalingam

    2015-07-01

    Marine actinobacteria are known to be a rich source for novel metabolites with diverse biological activities. In this study, a potential extracellular L-asparaginase was characterised from the Streptomyces griseus NIOT-VKMA29. Box-Behnken based optimization was used to determine the culture medium components to enhance the L-asparaginase production. pH, starch, yeast extract and L-asparagine has a direct correlation for enzyme production with a maximum yield of 56.78 IU mL-1. A verification experiment was performed to validate the experiment and more than 99% validity was established. L-Asparaginase biosynthesis gene (ansA) from Streptomyces griseus NIOT-VKMA29 was heterologously expressed in Escherichia coli M15 and the enzyme production was increased threefold (123 IU mL-1) over the native strain. The ansA gene sequences reported in this study encloses several base substitutions with that of reported sequences in GenBank, resulting in altered amino acid sequences of the translated protein.

  14. ATP-Binding Cassette Transport System Involved in Regulation of Morphological Differentiation in Response to Glucose in Streptomyces griseus

    PubMed Central

    Seo, Jeong-Woo; Ohnishi, Yasuo; Hirata, Aiko; Horinouchi, Sueharu

    2002-01-01

    Streptomyces griseus NP4, which was derived by UV mutagenesis from strain IFO13350, showed a bald and wrinkled colony morphology in response to glucose. Mutant NP4 formed ectopic septa at intervals along substrate hyphae, and each of the compartments developed into a spore which was indistinguishable from an aerial spore in size, shape, and thickness of the spore wall and in susceptibility to lysozyme and heat. The ectopic spores of NP4 formed in liquid medium differed from “submerged spores” in lysozyme sensitivity. Shotgun cloning experiments with a library of the chromosomal DNA of the parental strain and mutant NP4 as the host gave rise to DNA fragments giving two different phenotypes; one complementing the bald phenotype of the host, and the other causing much severe wrinkled morphology in the host. Subcloning identified a gene (dasR) encoding a transcriptional repressor belonging to the GntR family that was responsible for the reversal of the bald phenotype and a gene (dasA) encoding a lipoprotein probably serving as a substrate-binding protein in an ATP-binding cassette (ABC) transport system that was responsible for the severe wrinkled morphology. These genes were adjacent but divergently encoded. Two genes, named dasB and dasC, encoding a membrane-spanning protein were present downstream of dasA, which suggested that dasRABC comprises a gene cluster for an ABC transporter, probably for sugar import. dasR was transcribed actively during vegetative growth, and dasA was transcribed just after commencement of aerial hypha formation and during sporulation, indicating that both were developmentally regulated. Transcriptional analysis and direct sequencing of dasRA in mutant NP4 suggested a defect of this mutant in the regulatory system to control the expression of these genes. Introduction of multicopies of dasA into the wild-type strain caused ectopic septation in very young substrate hyphae after only 1 day of growth and subsequent sporulation in response

  15. Control of the Streptomyces Subtilisin Inhibitor Gene by AdpA in the A-Factor Regulatory Cascade in Streptomyces griseus

    PubMed Central

    Hirano, Setsu; Kato, Jun-ya; Ohnishi, Yasuo; Horinouchi, Sueharu

    2006-01-01

    AdpA in the A-factor regulatory cascade in Streptomyces griseus activates a number of genes required for secondary metabolism and morphological differentiation, forming an AdpA regulon. The Streptomyces subtilisin inhibitor (SSI) gene, sgiA, in S. griseus was transcribed in response to AdpA, showing that sgiA is a member of the AdpA regulon. AdpA bound a single site upstream of the sgiA promoter at approximately position −70 with respect to its transcriptional start point. Mutational analysis of the AdpA-binding site showed that the AdpA-binding site was essential for transcriptional activation. Mutants in which sgiA was disrupted had higher trypsin, chymotrypsin, metalloendopeptidase, and total protease activities than the wild-type strain, which showed that SgiA modulated the activities of these extracellularly produced proteases. Because a number of genes encoding chymotrypsins, trypsins, and metalloendopeptidases, most of which are SSI-sensitive proteases, are also under the control of AdpA, the A-factor regulatory cascade was thought to play a crucial role in modulating the extracellular protease activities by triggering simultaneous production of the proteases and their inhibitor at a specific timing during growth. Mutants in which sgiA was disrupted grew normally and formed aerial hyphae and spores with the same time course as the wild-type strain. However, exogenous addition of purified SgiA to substrate mycelium grown on agar medium resulted in a delay in aerial mycelium formation, indicating that SgiA is involved in aerial hypha formation in conjunction with proteases. PMID:16923887

  16. Control of the Streptomyces Subtilisin inhibitor gene by AdpA in the A-factor regulatory cascade in Streptomyces griseus.

    PubMed

    Hirano, Setsu; Kato, Jun-ya; Ohnishi, Yasuo; Horinouchi, Sueharu

    2006-09-01

    AdpA in the A-factor regulatory cascade in Streptomyces griseus activates a number of genes required for secondary metabolism and morphological differentiation, forming an AdpA regulon. The Streptomyces subtilisin inhibitor (SSI) gene, sgiA, in S. griseus was transcribed in response to AdpA, showing that sgiA is a member of the AdpA regulon. AdpA bound a single site upstream of the sgiA promoter at approximately position -70 with respect to its transcriptional start point. Mutational analysis of the AdpA-binding site showed that the AdpA-binding site was essential for transcriptional activation. Mutants in which sgiA was disrupted had higher trypsin, chymotrypsin, metalloendopeptidase, and total protease activities than the wild-type strain, which showed that SgiA modulated the activities of these extracellularly produced proteases. Because a number of genes encoding chymotrypsins, trypsins, and metalloendopeptidases, most of which are SSI-sensitive proteases, are also under the control of AdpA, the A-factor regulatory cascade was thought to play a crucial role in modulating the extracellular protease activities by triggering simultaneous production of the proteases and their inhibitor at a specific timing during growth. Mutants in which sgiA was disrupted grew normally and formed aerial hyphae and spores with the same time course as the wild-type strain. However, exogenous addition of purified SgiA to substrate mycelium grown on agar medium resulted in a delay in aerial mycelium formation, indicating that SgiA is involved in aerial hypha formation in conjunction with proteases. PMID:16923887

  17. Three Chymotrypsin Genes Are Members of the AdpA Regulon in the A-Factor Regulatory Cascade in Streptomyces griseus

    PubMed Central

    Tomono, Ayami; Tsai, Yisan; Ohnishi, Yasuo; Horinouchi, Sueharu

    2005-01-01

    AdpA is a key transcriptional activator in the A-factor regulatory cascade in Streptomyces griseus, activating a number of genes required for secondary metabolism and morphological differentiation. Of the five chymotrypsin-type serine protease genes, sprA, sprB, and sprD were transcribed in response to AdpA, showing that these protease genes are members of the AdpA regulon. These proteases were predicted to play the same physiological role, since these protease genes were transcribed in a similar time course during growth and the matured enzymes showed high end-to-end similarity to one another. AdpA bound two sites upstream of the sprA promoter approximately at positions −375 and −50 with respect to the transcriptional start point of sprA. Mutational analysis of the AdpA-binding sites showed that both AdpA-binding sites were essential for transcriptional activation. AdpA bound a single site at position −50 in front of the sprB promoter and greatly enhanced the transcription of sprB. The AdpA-binding site at position −40 was essential for transcription of sprD, although there was an additional AdpA-binding site at position −180. Most chymotrypsin activity excreted by S. griseus was attributed to SprA and SprB, because mutant ΔsprAB, having a deletion in both sprA and sprB, lost almost all chymotrypsin activity, as did mutant ΔadpA. Even the double mutant ΔsprAB and triple mutant ΔsprABD grew normally and developed aerial hyphae and spores over the same time course as the wild-type strain. PMID:16159767

  18. Transcriptional Control by A-Factor of strR, the Pathway-Specific Transcriptional Activator for Streptomycin Biosynthesis in Streptomyces griseus

    PubMed Central

    Tomono, Ayami; Tsai, Yisan; Yamazaki, Haruka; Ohnishi, Yasuo; Horinouchi, Sueharu

    2005-01-01

    A-factor (2-isocapryloyl-3R-hydroxymethyl-γ-butyrolactone) triggers streptomycin production by inducing the transcription of strR, encoding the pathway-specific transcriptional activator, through signal transduction in the A-factor regulatory cascade in Streptomyces griseus. AdpA, one of the key transcriptional activators in the cascade, bound two upstream activation sites, approximately at nucleotide positions −270 and −50 with respect to the transcriptional start point of strR, as determined by gel mobility shift assays and DNase I footprinting. Transcriptional analysis of the strR promoter with mutated AdpA-binding sites showed that both sites were required for full transcriptional activation of strR by AdpA. Potassium permanganate footprinting showed that AdpA assisted RNA polymerase in forming an open complex at an appropriate position for transcriptional initiation of strR. Nine transcriptional units within the streptomycin biosynthesis gene cluster, including the strR-aphD operon, depended on StrR, indicating that StrR is the pathway-specific transcriptional activator for the whole gene cluster. Consistent with this, expression of strR under the control of a constitutively expressed promoter in an adpA null mutant caused the host to produce streptomycin. PMID:16077104

  19. A Single Target Is Sufficient To Account for the Biological Effects of the A-Factor Receptor Protein of Streptomyces griseus

    PubMed Central

    Kato, Jun-ya; Miyahisa, Ikuo; Mashiko, Mari; Ohnishi, Yasuo; Horinouchi, Sueharu

    2004-01-01

    In the model of the A-factor (2-isocapryloyl-3R-hydroxymethyl-γ-butyrolactone) regulatory cascade in Streptomyces griseus, A-factor binds ArpA, the A-factor receptor protein, that has bound to the adpA promoter and dissociates it from the DNA, thus inducing the transcription of adpA. AdpA switches on the transcription of a number of genes required for secondary metabolism and morphological differentiation, forming an AdpA regulon. Consistent with this model, arpA null mutants produced streptomycin and a yellow pigment in larger amounts and formed aerial hyphae from an earlier growth stage than the wild-type strain. On the other hand, mutant MK2, expressing a mutant ArpA (Trp119Ala), neither produced secondary metabolites nor formed aerial hyphae, because this A-factor-insensitive mutant ArpA always bound to and repressed the adpA promoter due to the amino acid replacement of Trp-119 with Ala. Introduction of adpA under the control of a foreign promoter into mutant MK2 restored all of the phenotypes that we could observe, which suggests that the only significant target of ArpA is adpA. In contrast to other γ-butyrolactone regulatory systems, disruption of arpA had no effect on A-factor production, indicating that ArpA does not regulate A-factor biosynthesis. Instead, A-factor production was found to be repressed by AdpA in a two-step regulatory feedback loop. PMID:15028707

  20. The proteolytic enzymes of the K-1 strain of Streptomyces griseus obtained from a commercial preparation (Pronase). Specificity and immobilization of aminopeptidase.

    PubMed

    Vosbeck, K D; Greenberg, B D; Awad, W M

    1975-05-25

    We recently described the purification of two aminopeptidases from Streptomyces griseus (Vosbeck, K.D., Chow, K.-F., and Awad, W.M., Jr. (1973) J. Biol. Chem. 248, 6329-6034). An analysis of the amino acid composition reveals very little differences in the two proteins. Each protein has alanine as the NH2-terminal residue. The aminopeptidases were treated separately with acetic anhydride; as noted in the past, the presence of glycerol is required to achieve excellent yields of acetylated active derivatives (Siegel, S., and Awad, W.M., Jr. (1973 J. Biol. Chem. 248, 3233-3240). However, in the present case much higher concentrations of glycerol (50%) are needed during acetylation to obtain derivatives with completely reacted NH2-terminal residues. The epsilon-amino groups were not completely acetylated. In contrast to the native enzymes, the acetylated derivatives show an affinity for DEAE-cellulose, a property consonant with the changes in net charge. The kinetic constants for each enzyme against L-leucine-p-nitroanilide do not change significantly after acetylation. The specificities of the two aminopeptidases were examined extensively on a semiquantitative basis. The activities are not restricted by the length of substrate chains. Each enzyme shows a preference for hydrophobic residues at the ultimate and penultimate positions. Charge residues are released a slower rates. No prolidase activity is demonstrable even at high enzyme to substrate ratios; however, NH2-terminal proline residues are released readily. D-Amino acid residues at the ultimate or penultimate position substantially reduce the rate of hydrolysis; D-leucyl-D-leucine is not hydrolyzed... PMID:805135

  1. Transcriptional Switch On of ssgA by A-Factor, Which Is Essential for Spore Septum Formation in Streptomyces griseus

    PubMed Central

    Yamazaki, Haruka; Ohnishi, Yasuo; Horinouchi, Sueharu

    2003-01-01

    A-factor (2-isocapryloyl-3R-hydroxymethyl-γ-butyrolactone) triggers morphological development and secondary metabolism in Streptomyces griseus. A transcriptional activator (AdpA) in the A-factor regulatory cascade switches on a number of genes required for both processes. AdBS11 was identified in a library of the DNA fragments that are bound by AdpA and mapped upstream of ssgA, which is essential for septum formation in aerial hyphae. Gel mobility shift assays and DNase I footprinting revealed three AdpA-binding sites at nucleotide positions about −235 (site 1), −110 (site 2), and +60 (site 3) with respect to the transcriptional start point, p1, of ssgA. ssgA had two transcriptional start points, one starting at 124 nucleotides (p1) and the other starting at 79 nucleotides (p2) upstream of the start codon of ssgA. Of the three binding sites, only sites 1 and 2 were required for transcriptional activation of p1 and p2 by AdpA. The transcriptional switch on of ssgA required the extracytoplasmic function sigma factor, σAdsA, in addition to AdpA. However, it was unlikely that σAdsA recognized the two ssgA promoters, since their −35 and −10 sequences were not similar to the promoter sequence motifs recognized by σBldN, a σAdsA homologue of Streptomyces coelicolor A3(2). An ssgA disruptant formed aerial hyphae, but did not form spores, irrespective of the carbon source of the medium, which indicated that ssgA is a member of the whi genes. Transcriptional analysis of ssfR, located just upstream of ssgA and encoding an IclR-type transcriptional regulator, suggested that no read-through from ssfR into ssgA occurred, and ssgA was transcribed in the absence of ssfR. ssgA was thus found to be controlled by AdpA and not by SsfR to a detectable extent. SsfR appeared to regulate spore septum formation independently of SsgA or through interaction with SsgA in some unknown way, because an ssfR disruptant also showed a whi phenotype. PMID:12562798

  2. Complex Structure of the DNA-binding Domain of AdpA, the Global Transcription Factor in Streptomyces griseus, and a Target Duplex DNA Reveals the Structural Basis of Its Tolerant DNA Sequence Specificity*

    PubMed Central

    Yao, Ming Dong; Ohtsuka, Jun; Nagata, Koji; Miyazono, Ken-ichi; Zhi, Yuehua; Ohnishi, Yasuo; Tanokura, Masaru

    2013-01-01

    AdpA serves as the global transcription factor in the A-factor regulatory cascade, controlling the secondary metabolism and morphological differentiation of the filamentous bacterium Streptomyces griseus. AdpA binds to over 500 operator regions with the consensus sequence 5′-TGGCSNGWWY-3′ (where S is G or C, W is A or T, Y is T or C, and N is any nucleotide). However, it is still obscure how AdpA can control hundreds of genes. To elucidate the structural basis of this tolerant DNA recognition by AdpA, we focused on the interaction between the DNA-binding domain of AdpA (AdpA-DBD), which consists of two helix-turn-helix motifs, and a target duplex DNA containing the consensus sequence 5′-TGGCGGGTTC-3′. The crystal structure of the AdpA-DBD-DNA complex and the mutant analysis of AdpA-DBD revealed its unique manner of DNA recognition, whereby only two arginine residues directly recognize the consensus sequence, explaining the strict recognition of G and C at positions 2 and 4, respectively, and the tolerant recognition of other positions of the consensus sequence. AdpA-DBD confers tolerant DNA sequence specificity to AdpA, allowing it to control hundreds of genes as a global transcription factor. PMID:24019524

  3. Hydrochemical and isotopic properties of the Mahmutlu and Bağdatoğlu mineralized thermal springs, Krşehir, Turkey

    NASA Astrophysics Data System (ADS)

    Ünsal, N.; Afşin, M.

    1999-12-01

    The present study identifies the hydrochemical and isotopic properties of the Mahmutlu and Bağdatoğlu mineralized thermal springs in Krşehir province, a geothermal field in central Anatolia, Turkey. Based on these properties, a hydrogeological regime is proposed in order to explain the Mahmutlu-Bağdatoğlu geothermal system. The relation between the concentrations of the environmental stable isotopes deuterium and oxygen-18 in the water is similar to the relationship in global meteoric water, indicating that the water is of meteoric origin. Evaluation of the geochemical characteristics of the water reveals that these two thermal springs belong to the same hydrogeological system. The hydrogeological system comprises a fractured limestone member of the Çevirme Formation and the Kervansaray Formation as reservoir rocks, and the Delicermak Formation as an overlying aquitard. The waters of the Mahmutlu and Bağdatoğlu springs are mainly of the Na-Cl-SO4 type that originate from the Pohrenk evaporite. The thermal waters are undersaturated with respect to calcite, dolomite, halite, and gypsum. The δ18O and δ2H contents indicate a δ18O shift in the Mahmutlu and Bağdatoğlu waters. The temperature range of the two reservoirs is estimated to be 98-158 °C, on the basis of Na+K+Ca and SiO2 geothermometers. RésuméCette étude présente les caractéristiques chimiques et isotopiques des sources thermales minéralisées de Mahmutlu et de Bağdatoğlu, dans la province de Krşehir, un champ géothermal d'Anatolie centrale (Turquie). Un fonctionnement hydrogéologique est proposéà partir de ces caractéristiques, permettant d'expliquer le système géothermal de Mahmatlu-Bağdatoğlu. La relation entre les teneurs en deutérium et celles en oxygène-18 des eaux est semblable à celle des eaux météoriques mondiales, ce qui indique que l'eau est d'origine météorique. Les caractéristiques géochimiques des eaux de ces deux sources montrent qu'elles appartiennent au

  4. Feeding Behavior of Subadult Sixgill Sharks (Hexanchus griseus) at a Bait Station

    PubMed Central

    McNeil, Bryan; Lowry, Dayv; Larson, Shawn; Griffing, Denise

    2016-01-01

    This is the first in-situ study of feeding behaviors exhibited by bluntnose sixgill sharks. Bait was placed beneath the Seattle Aquarium pier situated on the waterfront in Elliott Bay, Puget Sound, Washington at 20m of water depth. Cameras and lights were placed around the bait box to record sixgill shark presence and behavior while feeding. Analysis of feeding behavior revealed that sixgills utilize a bite comparable to many other elasmobranchs and aquatic vertebrates, have the ability to protrude their upper jaw, change their feeding behavior based on the situation, and employ sawing and lateral tearing during manipulation. The versatility of their feeding mechanism and the ability of sixgills to change their capture and food manipulation behaviors may have contributed to the species’ worldwide distribution and evolutionary success. PMID:27243237

  5. Feeding Behavior of Subadult Sixgill Sharks (Hexanchus griseus) at a Bait Station.

    PubMed

    McNeil, Bryan; Lowry, Dayv; Larson, Shawn; Griffing, Denise

    2016-01-01

    This is the first in-situ study of feeding behaviors exhibited by bluntnose sixgill sharks. Bait was placed beneath the Seattle Aquarium pier situated on the waterfront in Elliott Bay, Puget Sound, Washington at 20m of water depth. Cameras and lights were placed around the bait box to record sixgill shark presence and behavior while feeding. Analysis of feeding behavior revealed that sixgills utilize a bite comparable to many other elasmobranchs and aquatic vertebrates, have the ability to protrude their upper jaw, change their feeding behavior based on the situation, and employ sawing and lateral tearing during manipulation. The versatility of their feeding mechanism and the ability of sixgills to change their capture and food manipulation behaviors may have contributed to the species' worldwide distribution and evolutionary success. PMID:27243237

  6. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (South Florida): Gray, lane, mutton, and yellowtail snappers. [Lutjanus griseus; Lutjanus synagris; Lutjanus analis; Ocyurus chrysurus

    SciTech Connect

    Bortone, S.A.; Williams, J.L.

    1986-06-01

    These four snapper species have similar morphologies as well as life history and environmental requirements. With some exceptions they are restricted to tropical and subtropical coastal areas of the western Atlantic. Adults often associate with coral reef and other hard-bottom communities. Juveniles and pre-adults usually inhabit shallow, inshore areas and are often found in seagrass beds. Reproduction usually takes place offshore in the warmer months of the year. Fecundity is positively related to female body size, but there is substantial variation both within and among the species. Juveniles obtain adult body proportions at about 50 mm SL. Approximate total maximum lengths of adults are 900 mm for gray snapper, 446 mm for lane snapper, and 750 mm for mutton and yellowtail snappers. Otoliths are the most preferred body part used to determine age. Most snappers attain sexual maturity after 3 to 5 years at a size range of 180 to 350 mm FL. Males mature at a smaller size than females. Recent commercial catches of gray and lane snappers have been increasing, whereas mutton and yellowtail snappers show no clear trends. Sport fishing probably has a substantial impact on the stocks of all four species. All four snappers feed predominantly on small benthic fishes and crustaceans, but yellowtail snapper feed on more pelagic animals. Upper water temperature tolerance limits are 27.2 to 32.5/sup 0/C and lower limits are 11 to 14/sup 0/C.

  7. Projecting Range Limits with Coupled Thermal Tolerance - Climate Change Models: An Example Based on Gray Snapper (Lutjanus griseus) along the U.S. East Coast

    PubMed Central

    Hare, Jonathan A.; Wuenschel, Mark J.; Kimball, Matthew E.

    2012-01-01

    We couple a species range limit hypothesis with the output of an ensemble of general circulation models to project the poleward range limit of gray snapper. Using laboratory-derived thermal limits and statistical downscaling from IPCC AR4 general circulation models, we project that gray snapper will shift northwards; the magnitude of this shift is dependent on the magnitude of climate change. We also evaluate the uncertainty in our projection and find that statistical uncertainty associated with the experimentally-derived thermal limits is the largest contributor (∼ 65%) to overall quantified uncertainty. This finding argues for more experimental work aimed at understanding and parameterizing the effects of climate change and variability on marine species. PMID:23284974

  8. Laminar and cytoarchitectonic features of the cerebral cortex in the Risso's dolphin (Grampus griseus), striped dolphin (Stenella coeruleoalba), and bottlenose dolphin (Tursiops truncatus).

    PubMed

    Furutani, Rui

    2008-09-01

    The present investigation carried out Nissl, Klüver-Barrera, and Golgi studies of the cerebral cortex in three distinct genera of oceanic dolphins (Risso's dolphin, striped dolphin and bottlenose dolphin) to identify and classify cortical laminar and cytoarchitectonic structures in four distinct functional areas, including primary motor (M1), primary sensory (S1), primary visual (V1), and primary auditory (A1) cortices. The laminar and cytoarchitectonic organization of each of these cortical areas was similar among the three dolphin species. M1 was visualized as five-layer structure that included the molecular layer (layer I), external granular layer (layer II), external pyramidal layer (layer III), internal pyramidal layer (layer V), and fusiform layer (layer VI). The internal granular layer was absent. The cetacean sensory-related cortical areas S1, V1, and A1 were also found to have a five-layer organization comprising layers I, II, III, V and VI. In particular, A1 was characterized by the broadest layer I, layer II and developed band of pyramidal neurons in layers III (sublayers IIIa, IIIb and IIIc) and V. The patch organization consisting of the layer IIIb-pyramidal neurons was detected in the S1 and V1, but not in A1. The laminar patterns of V1 and S1 were similar, but the cytoarchitectonic structures of the two areas were different. V1 was characterized by a broader layer II than that of S1, and also contained the specialized pyramidal and multipolar stellate neurons in layers III and V. PMID:18625031

  9. Proteolytic enzymes of the K-1 strain of Streptomyces griseus obtained from a commercial preparation (Pronase). Purification and characterization of the carboxypeptidase.

    PubMed

    Seber, J F; Toomey, T P; Powell, J T; Brew, K; Awad, W M

    1976-01-10

    We described earlier the facilitated purifications of the trypsin and aminopeptidase components present in Pronase (Vosbeck, K. D., Chow, K. -F., and Awad, W. M., Jr. (1973) J. Biol. Chem. 248, 6029-6034). A partially resolved protein mixture left over after one of the steps in that procedure was passed through a Sephadex G-75 column. By this means, a component with carboxypeptidase activity was separated from associated serine endopeptidases. Further purification of this exopeptidase to apparent homogeneity was acheived by refiltration through the same Sephadex column and by CM-cellulose chromatography. A single protein band was observed after acrylamide gel electrophoresis; analysis by sedimentation equilibrium using the meniscus depletion method gave a molecular weight of 30,300. This enzyme demonstrates activity against Nalpha-benzyloxycarbonylglycyl-L-leucine and hippuryl-D,L-phenyllactate; no activity was found against Nalpha-acetyl-L-tyrosine ethyl ester, Nalpha-benzoyl-D,L-arginine-p-nitroanilide, or L-leuckne-p-nitroanilide. The maximum activity lies between pH values of 7 and 8; the enzyme is stable between pH values of 6 and 10. At room temperature 1,10-phenanthroline inactivates the enzyme completely whereas EDTA has no effect. Of the many cations tested, only Co2+, Ni2+, or Zn2+ restores activity to the 1,10-phenanthroline-treated enzyme; Co2+ provided 3 times the native activity. The metal in the native protein was found to be zinc. These findings are similar to those recorded with bovine pancreatic carboxypeptidase A, and suggest the possibility that the present enzyme may ge genetically related to the mammalian protein, as in previously noted examples of homology of three Pronase endopeptidases to pancreatic serine enzymes. PMID:399

  10. Datos Historicos de Puerto Rico (Historical Facts on Puerto Rico). Preliminary Edition.

    ERIC Educational Resources Information Center

    Chicago Board of Education, IL. Dept. of Curriculum.

    A volume of information about Puerto Rican history and culture is designed for use by teachers in the bilingual education program of the Chicago public schools to support cultural awareness among native Spanish-speaking students. Six chapters outline important information concerning: the history of Puerto Rico, some aspects of the life of the…

  11. La Asociación OB Bochum7 combinando datos IR y ópticos

    NASA Astrophysics Data System (ADS)

    Corti, M. A.; Bosch, G. L.; Niemela, V. S.

    We present the results of an analysis of IR data in the region of the galactic OB association Bo7, obtained from the archives of the IRAS satellite mission and the 2MASS survey. Bo7 is located at the end of Perseus spiral arm. Distances of possible members of the Bo7 association were determined calculating the absorption from the E(V-K) colour excess. These members had been previously selected according to their UBV colours and spectra. The distance values obtained with IR excess have a smaller error than those obtained considering the E(B-V) excess. An extended interstellar dust cloud (detected in IRAS maps) is found to be probably associated with the members of Bo7. Two IRAS point sources observed in the region have characteristics of star formation sites. One of these point sources has been observed in CS(2-1) by Bronfman et al. (1996), who determined a value of (LSR) velocity of 44 km/s, close to the velocity of stars in Bo7 (Corti et al. 2003). A group of main sequence O - B0.5 stars appear near the location of the aforementioned IRAS point source, suggesting sequential star formation in the Bo7 region.

  12. Longitudinal HIV Risk Behavior among the Drug Abuse Treatment Outcome Studies (DATOS) Adult Sample

    ERIC Educational Resources Information Center

    Murphy, Debra A.; Brecht, Mary-Lynn; Herbeck, Diane; Evans, Elizabeth; Huang, David; Hser, Yih-Ing

    2008-01-01

    Longitudinal trajectories for HIV risk were examined over 5 years following treatment among 1,393 patients who participated in the nationwide Drug Abuse Treatment Outcome Studies. Both injection drug use and sexual risk behavior declined over time, with most of the decline occurring between intake and the first-year follow-up. However, results of…

  13. Prospective Risk Factors and Treatment Outcomes among Adolescents in DATOS-A.

    ERIC Educational Resources Information Center

    Galaif, Elisha R.; Hser, Yih-Ing; Grella, Christine E.; Joshi, Vandana

    2001-01-01

    Relationships between risk factors and outcomes were examined for Drug Abuse Treatment Outcome Studies for Adolescents participants. For outpatient drug-free participants, drug use severity predicted less treatment retention; family drug involvement predicted more alcohol use after treatment. For residential participants, family drug involvement…

  14. Faridah bt. Dato Talib v. Mohd. Habibullah bin Mahmood [14 October 1989].

    PubMed

    1989-01-01

    The Malaysian court held that a Muslim wife could sue her Muslim husband for damages arising from assault and battery. It rejected the husband's argument that the suit must be adjudicated in a religious court because it was related to marriage, a topic for Muslims handled exclusively by religious courts. It concluded that assault and battery were not marital matters but criminal law matters. Moreover, it ruled for the same reason that the suit was not precluded by the Married Women Ordinance 1957, which prohibits a wife from suing her husband in tort, except for the protection or security of her property. PMID:12344524

  15. Funciones de partición atómicas: Fuentes confiables de datos

    NASA Astrophysics Data System (ADS)

    Merlo, D. C.; Milone, L. A.

    Se llevó a cabo una revisión minuciosa del cálculo de funciones de partición atómicas de átomos livianos, en estados neutro y una vez ionizados, partiendo del Hidrógeno y llegando al Sodio, incluyendo también al K I y el Ca II. Al respecto, se realizó una investigación exhaustiva de referencias bibliográficas existentes hasta el presente, las cuales fueron cotejadas con cálculos propios llevados a cabo mediante el procedimiento de depresión del contínuo (0.001 a 0.5 eV). Nuestros resultados muestran un muy buen acuerdo con las expresiones interpolatorias de Traving et al (1966), al presente, la referencia más completa en cuanto a especies atómicas consideradas. Puntualizamos, además, ciertas deficiencias de estas relaciones de ajuste para decrementos del potencial de ionización altos (Δ χ >= 0.5) eV).

  16. Diseno y desarrollo de una base de datos bibliograficos (Design and Development of a Bibliographic Database).

    ERIC Educational Resources Information Center

    Mattenella, L. E.; Velazco, J. W.

    1992-01-01

    This article briefly describes the development of bibliographic retrieval systems in the Instituto de Beneficio di Minerales (IN BE MI) in Salta, Argentina, using the Mini-micro CDS/ISIS software developed by Unesco. (LRW)

  17. NIDA-Drug Addiction Treatment Outcome Study (DATOS) Relapse as a Function of Spirituality/Religiosity

    PubMed Central

    Schoenthaler, Stephen J.; Blum, Kenneth; Braverman, Eric R.; Giordano, John; Thompson, Ben; Oscar-Berman, Marlene; Badgaiyan, Rajendra D.; Madigan, Margaret A.; Dushaj, Kristina; Li, Mona; Demotrovics, Zsolt; Waite, Roger L.; Gold, Mark S.

    2015-01-01

    Background The connection between religion/spirituality and deviance, like substance abuse, was first made by Durkheim who defined socially expected behaviors as norms. He explained that deviance is due in large part to their absence (called anomie), and concluded that spirituality lowers deviance by preserving norms and social bonds. Impairments in brain reward circuitry, as observed in Reward Deficiency Syndrome (RDS), may also result in deviance and as such we wondered if stronger belief in spirituality practice and religious belief could lower relapse from drugs of abuse. Methods The NIDA Drug Addiction Treatment Outcome Study data set was used to examine post hoc relapse rates among 2,947 clients who were interviewed at 12 months after intake broken down by five spirituality measures. Results Our main findings strongly indicate, that those with low spirituality have higher relapse rates and those with high spirituality have higher remission rates with crack use being the sole exception. We found significant differences in terms of cocaine, heroin, alcohol, and marijuana relapse as a function of strength of religious beliefs (x2 = 15.18, p = 0.028; logistic regression = 10.65, p = 0.006); frequency of attending religious services (x2 = 40.78, p < 0.0005; logistic regression = 30.45, p < 0.0005); frequency of reading religious books (x2 = 27.190, p < 0.0005; logistic regression = 17.31, p < 0.0005); frequency of watching religious programs (x2 = 19.02, p = 0.002; logistic regression = ns); and frequency of meditation/prayer (x2 = 11.33, p = 0.045; logistic regression = 9.650, p = 0.002). Across the five measures of spirituality, the spiritual participants reported between 7% and 21% less alcohol, cocaine, heroin, and marijuana use than the non-spiritual subjects. However, the crack users who reported that religion was not important reported significantly less crack use than the spiritual participants. The strongest association between remission and spirituality involves attending religious services weekly, the one marker of the five that involves the highest social interaction/social bonding consistent with Durkheim’s social bond theory. Conclusions Stronger spiritual/religious beliefs and practices are directly associated with remission from abused drugs except crack. Much like the value of having a sponsor, for clients who abuse drugs, regular spiritual practice, particularly weekly attendance at the religious services of their choice is associated with significantly higher remission. These results demonstrate the clinically significant role of spirituality and the social bonds it creates in drug treatment programs. PMID:26052556

  18. Búsqueda de Sitios para CTA: Análisis de Datos Satelitales

    NASA Astrophysics Data System (ADS)

    Suárez, A. E.; Medina, M. C.; Romero, G. E.

    The CTA Consortium has decided to implement a systematic search for sites for the Observatory. This search will be made in two different steps. The first one consists of a general determination of the possible sites on the basis of some very basic selection criteria, such as geographic latitude, altitude and extension of the flat area needed. For those sites passing these criteria, a more intensive characterization should be made, using available satellite data, together with existing ground or air-based measurements. In this work we compare the behavior of different sites analyzing the aerosol content and the total precipitable water vapor, measured by MODIS instrument. FULL TEXT IN SPANISH

  19. Clasificación de asterismos utilizando datos astrométricos

    NASA Astrophysics Data System (ADS)

    de Biasi, M. S.; Orellana, R. B.

    Based on accurate positions and proper motion data up to faint magnitudes, we have studied the regions of twenty three objects known in the literature as asterisms. A parametric method was applied to confirm the nature of these objects. The following objects have been classified: Alessi 11, Alessi 17, Brosch 1, Collinder 21, Dol-Dzim 1, Dolidze 31, Dolidze 43, Dolidze 50, Dolidze 51, NGC 272, NGC2063, NGC 2413, NGC 2664, NGC 5155, NGC 5284, NGC 6222, NGC 6360, NGC 6447, NGC 6476, NGC 6480, NGC 6605, NGC 6659, NGC 6728. FULL TEXT IN SPANISH

  20. Uso de los Datos de Biomonitoreo para Informar sobre la Evaluacion Infantil (American translation is: USING BIOMONITORING DATA TO INFORM EXPOSURE ASSESSMENT IN CHILDREN)

    EPA Science Inventory

    Discussing the challenges associated with estimating and interpreting toxicant exposures and health risks from biomonitoring data. This extended abstract was translated in Spanish and published in Acta Toxicologica Argentina.

  1. Consideraciones acerca del método de los arcos de reducción de datos VLBI astrométricos

    NASA Astrophysics Data System (ADS)

    de Biasi, M. S.; Arias, E. F.

    Con el propósito de construir un marco de referencia cuasi-inercial, desarrollamos un sistema de coordenadas inercial introduciendo un nuevo observable: el arco entre un par de radiofuentes. Este método proveerá una mejor herramienta para el análisis y reducción de observaciones VLBI. También conducirá a una solución en donde se determinarán independientemente los parámetros astrométricos y geodésicos. En este trabajo analizamos el caso ideal de observaciones simultáneas de un par de radiofuentes y el caso más realista de observaciones cuasisimultáneas.

  2. Extracción de conocimiento en bases de datos astronómicas mediante redes de neuronas artificiales: aplicaciones en la misión Gaia

    NASA Astrophysics Data System (ADS)

    Fustes Villadóniga, Diego

    2014-02-01

    In the so-called IT era, the capabilities of data acquisition systems have increased to such an extent that it has become difficult to store all the information they produce, and analyse it. This explosion of data has recently appeared in the field of Astronomy, where an increasing number of objects are being observed on a regular basis. An example of this is the upcoming Gaia mission, which will pick up multiple properties of a billion stars, whose information will have a volume of approximately a petabyte. The analysis of a similar amount of information inevitably requires the development of new data analysis methods to extract all the knowledge it contains. This thesis is devoted to the development of data analysis methods to be integrated in the Gaia pipeline, such that knowledge can be extracted from the data collected by the mission. In order to analyze the data from the Gaia mission, the European Space Agency organized the Data Processing and Analysis Consortium (DPAC) which is composed of hundreds of scientists and engineers. DPAC is divided into eight Coordination Units (CUs). This thesis is dedicated to algorithm development in CU8, which is responsible for source classification and astrophysical parameters (AP) estimation. Methods based on Artificial Neural Networks (ANNs) are developed to perform the tasks related to two different work packages in CU8: the GSP-Spec package (GWP-823), and the OA package (GWP-836). The GSP-Spec package is responsible for estimating stellar APs by means of the Radial Velocity Spectrograph (RVS) spectrum. This work presents the development of one of the GSP-Spec modules, which is based on the application of feed-forward ANNs. A methodology is described, based on the optimization of genetic algorithms and aimed at obtaining an optimal set of configuration parameters for the ANN in each case, depending on the signal to noise ratio (SNR) in the RVS spectrum and on the type of star to parameterize. Furthermore, in order to improve the AP estimates, wavelet signal processing techniques, applied to the RVS spectrum, are studied. Despite the effectiveness shown by ANNs in estimating APs, in principle they lack the ability to provide an uncertainty value on these estimates, making it impossible to determine their reliability. Because of this, a new architecture for the ANN is presented in which the inputs and outputs are reversed, so that the ANN estimates the RVS spectrum from the APs. Such an architecture is called Generative ANN (GANN) and is applied to the AP estimation of a set of simulated RVS spectra for the Gaia mission, where it is more effective than the conventional ANN model, in the case of faint stars with low SNR. Finally, the GANN can be applied for obtaining the posterior probability of each of the APs according to the RVS spectrum, allowing for their more complete analysis. Given the nature of the Gaia mission, which is the first astronomical mission that will observe, in an unbiased way, the entire sky up to magnitude 20, a large number of outliers are expected. The OA package in CU8 handles the processing of this type of objects, which are defined as those that could not be reliably classified by the methods in the upstream classification packages. OA methods are based on the unsupervised learning of all outliers. Such learning has two parts: clustering and dimensionality reduction. The Self-Organizing Map (SOM) algorithm is selected as a basis for this learning. Its effectiveness is demonstrated when it is applied, with an optimal configuration, to the Gaia simulations. Furthermore, the algorithm is applied to real outliers from the SDSS catalog. Since a subsequent identification of the clusters obtained by the SOM is necessary, two different methods of identification are applied. The first method is based on the similarity between the SOM prototypes and the Gaia simulations, and the second method is based on the recovery of stored classifications in the SIMBAD catalog by cross-matching celestial coordinates. Thanks to the visualization of the SOM planes, and to both methods of identification, it is possible to distinguish between valid observations and observational artifacts. Furthermore, the method allows for the selection of objects of interest for follow-up observations, in order to determine their nature.

  3. La Aplicacion de las Bases de Datos al Estudio Historico del Espanol (The Application of Databases to the Historical Study of Spanish).

    ERIC Educational Resources Information Center

    Nadal, Gloria Claveria; Lancis, Carlos Sanchez

    1997-01-01

    Notes that the employment of databases to the study of the history of a language is a method that allows for substantial improvement in investigative quality. Illustrates this with the example of the application of this method to two studies of the history of Spanish developed in the Language and Information Seminary of the Independent University…

  4. Extracción de conocimiento en bases de datos astronómicas mediante redes de neuronas artificiales: aplicaciones en la misión Gaia

    NASA Astrophysics Data System (ADS)

    Fustes Villadóniga, Diego

    2014-02-01

    In the so-called IT era, the capabilities of data acquisition systems have increased to such an extent that it has become difficult to store all the information they produce, and analyse it. This explosion of data has recently appeared in the field of Astronomy, where an increasing number of objects are being observed on a regular basis. An example of this is the upcoming Gaia mission, which will pick up multiple properties of a billion stars, whose information will have a volume of approximately a petabyte. The analysis of a similar amount of information inevitably requires the development of new data analysis methods to extract all the knowledge it contains. This thesis is devoted to the development of data analysis methods to be integrated in the Gaia pipeline, such that knowledge can be extracted from the data collected by the mission. In order to analyze the data from the Gaia mission, the European Space Agency organized the Data Processing and Analysis Consortium (DPAC) which is composed of hundreds of scientists and engineers. DPAC is divided into eight Coordination Units (CUs). This thesis is dedicated to algorithm development in CU8, which is responsible for source classification and astrophysical parameters (AP) estimation. Methods based on Artificial Neural Networks (ANNs) are developed to perform the tasks related to two different work packages in CU8: the GSP-Spec package (GWP-823), and the OA package (GWP-836). The GSP-Spec package is responsible for estimating stellar APs by means of the Radial Velocity Spectrograph (RVS) spectrum. This work presents the development of one of the GSP-Spec modules, which is based on the application of feed-forward ANNs. A methodology is described, based on the optimization of genetic algorithms and aimed at obtaining an optimal set of configuration parameters for the ANN in each case, depending on the signal to noise ratio (SNR) in the RVS spectrum and on the type of star to parameterize. Furthermore, in order to improve the AP estimates, wavelet signal processing techniques, applied to the RVS spectrum, are studied. Despite the effectiveness shown by ANNs in estimating APs, in principle they lack the ability to provide an uncertainty value on these estimates, making it impossible to determine their reliability. Because of this, a new architecture for the ANN is presented in which the inputs and outputs are reversed, so that the ANN estimates the RVS spectrum from the APs. Such an architecture is called Generative ANN (GANN) and is applied to the AP estimation of a set of simulated RVS spectra for the Gaia mission, where it is more effective than the conventional ANN model, in the case of faint stars with low SNR. Finally, the GANN can be applied for obtaining the posterior probability of each of the APs according to the RVS spectrum, allowing for their more complete analysis. Given the nature of the Gaia mission, which is the first astronomical mission that will observe, in an unbiased way, the entire sky up to magnitude 20, a large number of outliers are expected. The OA package in CU8 handles the processing of this type of objects, which are defined as those that could not be reliably classified by the methods in the upstream classification packages. OA methods are based on the unsupervised learning of all outliers. Such learning has two parts: clustering and dimensionality reduction. The Self-Organizing Map (SOM) algorithm is selected as a basis for this learning. Its effectiveness is demonstrated when it is applied, with an optimal configuration, to the Gaia simulations. Furthermore, the algorithm is applied to real outliers from the SDSS catalog. Since a subsequent identification of the clusters obtained by the SOM is necessary, two different methods of identification are applied. The first method is based on the similarity between the SOM prototypes and the Gaia simulations, and the second method is based on the recovery of stored classifications in the SIMBAD catalog by cross-matching celestial coordinates. Thanks to the visualization of the SOM planes, and to both

  5. Astrophysics in Schools: Playing with Observational Data. (Spanish Title: Astrofísica Escolar: Jugando con Datos Observacionales.) Astrofísica Escolar: Brincando com Dados Observacionais

    NASA Astrophysics Data System (ADS)

    Navone, Hugo D.; Scancich, Miriam; Vázquez, Rubén A.

    2011-07-01

    The use of observational records in the design of teaching sequences in Astrophysics in High Schools is quite uncommon. It is also uncommon the thematic approach within the context provided by Nature of Science. Besides these shortcomings, we should also consider the lack of proposals to use the computer as a laboratory from which nature is studied. These aspects expose the existence of a disconnection between school science and scientist's science, establishing the need for simple educational projects that promote interdisciplinary dialogue between the two fields of knowledge. Based on these assumptions, this paper presents the school reformulation of the redshift-distance problem as addressed by Hubble in his diagram, and explores the main educational dimensions emerging from it. The proposal is directed not only for senior students of high school and/or early 1st year students at University level, but also for students and teachers from teacher training colleges. Practical evidence shows that this proposal is viable, mobilizes interests about issues of Astrophysics and promotes a ludic and cooperative character among students. La utilización de registros observacionales en el diseño de secuencias didácticas en Astrofísica Escolar no es algo usual en el ámbito de la escuela media. Tampoco lo es el abordaje de temáticas desde el contexto que provee Naturaleza de la Ciencia. A estas carencias se le suma la falta de propuestas que hagan intervenir a la computadora como un laboratorio desde el cual se interpela a la naturaleza. Los aspectos mencionados exponen la existencia de un desajuste entre ciencia escolar y ciencia experta estableciendo la necesidad de elaborar proyectos educativos sencillos que promuevan el diálogo interdisciplinar entre ambos campos del conocimiento. Partiendo de estos presupuestos, en este trabajo se presenta la reformulación escolar del problema abordado por Hubble -que diera lugar al diagrama que lleva su nombre- y se exploran las principales dimensiones educativas que emergen del mismo. La propuesta está destinada a alumnos del último año de nivel medio y primeros años de la universidad, y a estudiantes y profesores de Institutos de Formación Docente. Las puestas en práctica realizadas muestran que la propuesta es viable, que moviliza inquietudes en torno a temáticas de Astrofísica y que se fortalece al adquirir un carácter lúdico y cooperativo. A utilização de registros observacionais na construção de seqüências didáticas em Astrofísica Escolar não é algo usual no ensino médio. Tampouco o é uma abordagem de temáticas dentro do contexto da Natureza da Ciência. Agrega-se a estas carências a falta de propostas que estimulem a utilização do computador como um laboratório para estudar a natureza. Os aspectos mencionados expõem a existência de um desajuste entre ciência escolar e ciência avançada, estabelecendo a necessidade de elaborar projetos educativos simples que promovam o diálogo interdisciplinar entre ambos campos do conhecimento. Partindo destes pressupostos, este trabalho apresenta a reformulação escolar do problema abordado por Hubble -a relação entre redshift e distância das galáxias- e se exploram as principais dimensões educativas que emergem do mesmo. A proposta está destinada a alunos do último ano do nível médio, primeiros anos do curso superior e a estudantes e professores de Institutos de Formação Docente. As atividades práticas realizadas mostram que a proposta é viável, que mobiliza inquietudes em torno da temática e da Astrofísica e que se fortalece ao adquirir um caráter lúdico e cooperativo.

  6. 50 CFR 216.161 - Specified activity and incidental take levels by species.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .... breviceps); pilot whale (Globicephala macrorhynchus); Atlantic spotted dolphin (Stenella frontalis); spinner dolphin (S. longirostris); bottlenose dolphin (Tursiops truncatus); Risso's dolphin (Grampus griseus); rough-toothed dolphin (Steno bredanensis); common dolphin (Delphinus delphis), false killer...

  7. 50 CFR 216.180 - Specified activity.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (Dephinapterus leucas), Stenella spp., Risso's dolphin (Grampus griseus), rough-toothed dolphin (Steno bredanensis), Fraser's dolphin (Lagenodelphis hosei), northern right-whale dolphin (Lissodelphis borealis), southern right whale dolphin (Lissodelphis peronii), short-beaked common dolphin (Delphius delphis),...

  8. 50 CFR 216.161 - Specified activity and incidental take levels by species.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... breviceps); pilot whale (Globicephala macrorhynchus); Atlantic spotted dolphin (Stenella frontalis); spinner dolphin (S. longirostris); bottlenose dolphin (Tursiops truncatus); Risso's dolphin (Grampus griseus); rough-toothed dolphin (Steno bredanensis); common dolphin (Delphinus delphis), false killer...

  9. 50 CFR 216.180 - Specified activity.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (Dephinapterus leucas), Stenella spp., Risso's dolphin (Grampus griseus), rough-toothed dolphin (Steno bredanensis), Fraser's dolphin (Lagenodelphis hosei), northern right-whale dolphin (Lissodelphis borealis), southern right whale dolphin (Lissodelphis peronii), short-beaked common dolphin (Delphius delphis),...

  10. 50 CFR 216.161 - Specified activity and incidental take levels by species.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .... breviceps); pilot whale (Globicephala macrorhynchus); Atlantic spotted dolphin (Stenella frontalis); spinner dolphin (S. longirostris); bottlenose dolphin (Tursiops truncatus); Risso's dolphin (Grampus griseus); rough-toothed dolphin (Steno bredanensis); common dolphin (Delphinus delphis), false killer...

  11. Taxonomy of the genus Lycalopex (Carnivora: Canidae) in Argentina

    USGS Publications Warehouse

    Zunino, G.E.; Vaccaro, O.B.; Canevari, M.; Gardner, A.L.

    1995-01-01

    Previously treated as species of Pseudalopex, Argentine members of the genus Lycalopex (L. griseus, L. gymnocercus, and L. culpaeus) are examined to clarify the taxonomic status of each named form. Principal components analyses of 26 cranial measurements of 151 adult specimens and 11 pelage characters of 111 specimens, clearly distinguish L. culpaeus from the other two taxa. Lycalopex griseus and L. gymnocercus show clinal variation in cranial measurements and pelage characters. Qualitative cranial characters, used as diagnostic for L. griseus and L. gymnocercus, revealed great nongeographic variation. We conclude that L. griseus and L. gymnocercus are conspecific, and should be known as L. gymnocercus. Therefore, we recognize only two species of the genus Lycalopex (L. culpaeus and L. gymnocercus) in Argentina. We also use this opportunity to review synonymies of the recognized species of Lycalopex.

  12. 75 FR 38078 - Incidental Taking of Marine Mammals; Taking of Marine Mammals Incidental to the Explosive Removal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ..., 2008 (73 FR 34875), and remain in effect through July 19, 2013. For detailed information on this action... bredanensis), Risso's dolphins (Grampus griseus), melon-headed whales (Peponocephala electra),...

  13. 50 CFR Appendix A to Part 635 - Species Tables

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., Carcharhinus isodon C. Pelagic Sharks Blue, Prionace glauca Oceanic whitetip, Carcharhinus longimanus Porbeagle..., Hexanchus griseus Smalltail, Carcharhinus porosus Whale, Rhincodon typus White, Carcharodon carcharias E... obesus Blue shark, Prionace glauca Bluefin tuna, Thunnus thynnus Dolphin fish, Coryphaena...

  14. Investigation of trophic level and niche partitioning of 7 cetacean species by stable isotopes, and cadmium and arsenic tissue concentrations in the western Pacific Ocean.

    PubMed

    Liu, J-Y; Chou, L-S; Chen, M-H

    2015-04-15

    A total of 24 stranded or bycatch cetaceans, including Balaenoptera omurai, Lagenodelphis hosei, Kogia sima, Stenella attenuata, Grampus griseus, Neophocaena phocaenoides, and Sousa chinensis, were collected from 2001 to 2011 in Taiwan. Using the muscular δ(13)C and δ(15)N data, three ecological groups were identified as the oceanic baleen whale, the neritic, and the coastal toothed whale groups, coinciding with their taxonomy, feeding habits and geographical distribution. A horizontal inshore to offshore distribution was found for the sympatric neritic toothed dolphins, G. griseus, K. sima, S. attenuata, and L. hosei in the outermost offshore waters, accompanying their growth. For the first time we identify Taiwan's Chinese white dolphin, S. chinensis, as an exclusive fish eater. Cd and As bioaccumulated in the G. griseus, L. hosei and S. attenuata increase as they grow. Prey-derived As- and Cd-induced health threats were found in L. hosei, and G. griseus. PMID:25684592

  15. Interconexión de la Estación Astrofísica de Bosque Alegre y la red local de datos del Observatorio Astronómico de Córdoba

    NASA Astrophysics Data System (ADS)

    Nicotra, M. A.; Anun, S.; Montes, M.; Goldes, G.; Carranza, G.

    We describe the outlines of a project for the interconnection between the Astrophysical Station of Bosque Alegre and the wide area network of the University of Córdoba. The Astrophysical Station is located 38.55 km (23.96 milles) from the Observatory of Córdoba. This location is suitable for radio links in the range of centimeters wavelenghts. In the last years, Spread-Spectrum technology equipments has become popular. Spread-Spectrum signals, contrary to narrow band radio signals, operates within a widthband 20 to 200 times broader than the widthband of the modulated information. Signals are modulated by special spreading codes, in such a way that emulates noisy signals. These codes are known under the generic designation of pseudo-random or pseudo-noise. In addition, the wide band is correlated with a low power density in the emitted signals. Spread-Spectrum equipment links are stable, exhibits low interferences with conventional radio transmitters, and their commercial prices are remarkably lower than those for the conventional microwave devices. Data links are compliant with Ethernet protocol networks and operates with data tramsmition rates up to 4 Mbits per second. The described equipment will enable the access to full-Internet services for visitor astronomers in Bosque Alegre. Also, it will be possible fast transfer for the observational data from telescope to computers in the local area network at Córdoba. This project must be considered as the second stage of another wide purpose project, which has the main purpose in transforming the Bosque Alegre Station as a fully robotic station controlled from the computational center at the Observatory in Cordoba. The advantages of robotic telescopes has recently been the subject of several discussions. However, it is now widely accepted that an automatic station enables some important options in the use of the astronomical instruments, such us the possibility of performing parallel programs, one of which is selected accordingly to environmental conditions in the instant of the observation.

  16. 50 CFR 218.181 - Permissible methods of taking.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (an average of 2 annually), (ii) Risso's dolphin (Grampus griseus)—10 (an average of 2 annually); (iii) Bottlenose dolphin (Tursiops truncatus)—3,070 (an average of 614 annually); (iv) Atlantic spotted dolphin (Stenella frontalis)—2,355 (an average of 471 annually); (v) Pantropical spotted dolphin (S....

  17. 50 CFR 218.102 - Permissible methods of taking.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (an average of 1,289 annually); (L) Striped dolphin (Stenella coeruleoalba)—44,290 (an average of 8,858 annually); (M) Short-beaked common dolphin (Delphinus delphis)—4,715 (an average of 943 annually); (N) Risso's dolphin (Grampus griseus)—33,865 (an average of 6,773 annually); (O) Bottlenose...

  18. 50 CFR 218.102 - Permissible methods of taking.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (an average of 1,289 annually); (L) Striped dolphin (Stenella coeruleoalba)—44,290 (an average of 8,858 annually); (M) Short-beaked common dolphin (Delphinus delphis)—4,715 (an average of 943 annually); (N) Risso's dolphin (Grampus griseus)—33,865 (an average of 6,773 annually); (O) Bottlenose...

  19. 50 CFR 218.112 - Permissible methods of taking.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (Globicephala macrorynchus)—10 (an average of 2 annually); (H) Striped dolphin (Stenella coeruleoalba)—200 (an average of 40 annually); (I) Short-beaked common dolphin (Globicephala macrorhynchus)—6280 (an average of 1256 annually); (J) Risso's dolphin (Grampus griseus)—500 (an average of 100 annually); (K)...

  20. 50 CFR 218.112 - Permissible methods of taking.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (Globicephala macrorynchus)—10 (an average of 2 annually); (H) Striped dolphin (Stenella coeruleoalba)—200 (an average of 40 annually); (I) Short-beaked common dolphin (Globicephala macrorhynchus)—6280 (an average of 1256 annually); (J) Risso's dolphin (Grampus griseus)—500 (an average of 100 annually); (K)...

  1. 50 CFR 218.181 - Permissible methods of taking.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (an average of 2 annually), (ii) Risso's dolphin (Grampus griseus)—10 (an average of 2 annually); (iii) Bottlenose dolphin (Tursiops truncatus)—3,070 (an average of 614 annually); (iv) Atlantic spotted dolphin (Stenella frontalis)—2,355 (an average of 471 annually); (v) Pantropical spotted dolphin (S....

  2. 50 CFR 218.181 - Permissible methods of taking.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (an average of 2 annually), (ii) Risso's dolphin (Grampus griseus)—10 (an average of 2 annually); (iii) Bottlenose dolphin (Tursiops truncatus)—3,070 (an average of 614 annually); (iv) Atlantic spotted dolphin (Stenella frontalis)—2,355 (an average of 471 annually); (v) Pantropical spotted dolphin (S....

  3. 50 CFR 218.102 - Permissible methods of taking.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (an average of 1,289 annually); (L) Striped dolphin (Stenella coeruleoalba)—44,290 (an average of 8,858 annually); (M) Short-beaked common dolphin (Delphinus delphis)—4,715 (an average of 943 annually); (N) Risso's dolphin (Grampus griseus)—33,865 (an average of 6,773 annually); (O) Bottlenose...

  4. 50 CFR 218.102 - Permissible methods of taking.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (an average of 1,289 annually); (L) Striped dolphin (Stenella coeruleoalba)—44,290 (an average of 8,858 annually); (M) Short-beaked common dolphin (Delphinus delphis)—4,715 (an average of 943 annually); (N) Risso's dolphin (Grampus griseus)—33,865 (an average of 6,773 annually); (O) Bottlenose...

  5. 50 CFR 218.102 - Permissible methods of taking.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (an average of 1,289 annually); (L) Striped dolphin (Stenella coeruleoalba)—44,290 (an average of 8,858 annually); (M) Short-beaked common dolphin (Delphinus delphis)—4,715 (an average of 943 annually); (N) Risso's dolphin (Grampus griseus)—33,865 (an average of 6,773 annually); (O) Bottlenose...

  6. 50 CFR 218.181 - Permissible methods of taking.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (an average of 2 annually), (ii) Risso's dolphin (Grampus griseus)—10 (an average of 2 annually); (iii) Bottlenose dolphin (Tursiops truncatus)—3,070 (an average of 614 annually); (iv) Atlantic spotted dolphin (Stenella frontalis)—2,355 (an average of 471 annually); (v) Pantropical spotted dolphin (S....

  7. 50 CFR 218.112 - Permissible methods of taking.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (Globicephala macrorynchus)—10 (an average of 2 annually); (H) Striped dolphin (Stenella coeruleoalba)—200 (an average of 40 annually); (I) Short-beaked common dolphin (Globicephala macrorhynchus)—6280 (an average of 1256 annually); (J) Risso's dolphin (Grampus griseus)—500 (an average of 100 annually); (K)...

  8. 50 CFR 218.112 - Permissible methods of taking.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (Globicephala macrorynchus)—10 (an average of 2 annually); (H) Striped dolphin (Stenella coeruleoalba)—200 (an average of 40 annually); (I) Short-beaked common dolphin (Globicephala macrorhynchus)—6280 (an average of 1256 annually); (J) Risso's dolphin (Grampus griseus)—500 (an average of 100 annually); (K)...

  9. 76 FR 37065 - Marine Mammals; File No. 14502

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ... FR 27286) that a request for a permit to import specimens for scientific research had been submitted... from Risso's (Grampus griseus), spinner (Stenella longirostris), and spotted (S. frontalis) dolphins... muscle, blubber, and teeth samples from Risso's, spinner, and spotted dolphins and short-finned...

  10. 77 FR 12010 - Marine Mammals; File Nos. 1076-1789 and 14502

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-28

    ... (72 FR 13092), authorized the receipt, import and export of marine mammal specimens (cetaceans and... June 17, 2011 (72 FR 13092), authorized the importation of samples from Risso's (Grampus griseus..., Colorado 80234 (Kristi West, Ph.D., Principal Investigator) and Russell Fielding, Ph.D., Department...

  11. 77 FR 13562 - Marine Mammals; File No. 14241

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-07

    ... INFORMATION: On December 16, 2011, notice was published in the Federal Register (76 FR 78242) that a request... following species in waters off the west coast of North America: Baird's beaked whale (Berardius bairdii), Cuvier's beaked whale (Ziphius cavirostris), Risso's dolphin (Grampus griseus), killer whale...

  12. 75 FR 29991 - Marine Mammals; receipt of application for permit amendment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-28

    ... July 15, 2009 (74 FR 3668), authorizes the permit holder to conduct research on cetacean behavior... (Globicephala macrorhynchus), long- finned pilot whale, Risso's dolphin (Grampus griseus), and false killer..., especially Cuvier's beaked whale (Ziphius cavirostris), and large delphinids such as long-finned pilot...

  13. 75 FR 47779 - Marine Mammals; File No. 14241

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-09

    ..., notice was published in the Federal Register (75 FR 29991) that a request for an amendment to the permit... (Grampus griseus), and false killer whale (Pseudorca crassidens). The new species for the project based off... beaked whale (Mesoplodon densirostris), Cuvier's beaked whale (Ziphius cavirostris), short-finned...

  14. First evidence of fish larvae producing sounds

    PubMed Central

    Staaterman, Erica; Paris, Claire B.; Kough, Andrew S.

    2014-01-01

    The acoustic ecology of marine fishes has traditionally focused on adults, while overlooking the early life-history stages. Here, we document the first acoustic recordings of pre-settlement stage grey snapper larvae (Lutjanus griseus). Through a combination of in situ and unprovoked laboratory recordings, we found that L. griseus larvae are acoustically active during the night, producing ‘knock’ and ‘growl’ sounds that are spectrally and temporally similar to those of adults. While the exact function and physiological mechanisms of sound production in fish larvae are unknown, we suggest that these sounds may enable snapper larvae to maintain group cohesion at night when visual cues are reduced. PMID:25274018

  15. [Production of vitamin B12 by fermentation].

    PubMed

    Oğultekin, R; Oner, M

    1985-10-01

    In this work, the methods and technology of vitamin B12 production were studied on laboratory scale. The microorganisms used for experiments were Streptomyces olivaceus IFO 3409, Streptomyces olivaceus CBS 355.53 and Streptomyces griseus CBS 161.45 which were brought from foreign countries. Vitamin B12 activity that have been obtained from fermentation experiments of each microorganisms are determined by microbiological assays using Lactobacillus leichmannii IFO 3073 (ATCC 4797) which is a test microorganism. As a result of these assays S. olivaceus IFO 3409 (2 micrograms/ml) was found as the most efficient strain were followed by S. olivaceus CBS 355.53 and S. griseus CBS 16.45 respectively. PMID:3938519

  16. A survey of the effects of proteases and glycosidases on culture of rabbit morulae to blastocysts.

    PubMed

    Kane, M T

    1986-09-01

    The effects of a range of commercially available proteases and glycosidases on blastocyst development and hatching were examined on rabbit embryos cultured from the morula stage in a defined medium supplemented with charcoal-treated bovine serum albumin. The proteases tested were trypsin, alpha-chymotrypsin, thrombin, elastase, plasmin, papain, clostripain, collagenase, Streptomyces griseus protease and cathepsin C. The glycosidases tested were neuraminidase, alpha-mannosidase, beta-galactosidase and hyaluronidase. None of these enzymes appeared to stimulate blastocyst growth. The only enzymes which digested the embryonic investments, the zona and mucin coat, sufficiently to cause complete blastocyst hatching were trypsin and Streptomyces griseus protease at relatively low concentrations (250 ng/ml) and chymotrypsin and elastase at higher concentrations. PMID:3531506

  17. Organizational and mutational analysis of a complete FR-008/candicidin gene cluster encoding a structurally related polyene complex.

    PubMed

    Chen, Shi; Huang, Xi; Zhou, Xiufen; Bai, Linquan; He, Jing; Jeong, Ki Jun; Lee, Sang Yup; Deng, Zixin

    2003-11-01

    The complete gene cluster for biosynthesis of a polyene complex, FR-008, spans 137.2 kb of the genome of Streptomyces sp. FR-008 consisting of six genes for a modular PKS and 15 additional genes. The extensive similarity to the partially characterized candicidin gene cluster in Streptomyces griseus IMRU3570, especially for genes involved in mycosamine biosynthesis, prompted us to compare the compounds produced by Streptomyces sp. FR-008 and Streptomyces griseus IMRU3570, and we found that FR-008 and candicidin complex are identical. A model for biosynthesis of a set of four structurally related FR-008/candicidin compounds was proposed. Deletion of the putative regulatory genes abolished antibiotic production, while disruption of putative glycosyltransferase and GDP-ketosugar aminotransferase functionalities led to the productions of a set of nonmycosaminated aglycones and a novel polyene complex with attachment of altered sugar moiety, respectively. PMID:14652074

  18. 9 CFR 3.104 - Space requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...'s dolphin 1.52 5.0 Delphinapterus leucas Beluga whale 4.27 14.0 Monodon monoceros Narwhale 3.96 13.0... 18.0 Grampus griseus Risso's dolphin 3.66 12.0 Orcinus orca Killer whale 7.32 24.0 Pseudorca carassidens False killer whale 4.35 14.3 Tursiops truncatus (Atlantic) Bottlenose dolphin 2.74 9.0...

  19. 9 CFR 3.104 - Space requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...'s dolphin 1.52 5.0 Delphinapterus leucas Beluga whale 4.27 14.0 Monodon monoceros Narwhale 3.96 13.0... 18.0 Grampus griseus Risso's dolphin 3.66 12.0 Orcinus orca Killer whale 7.32 24.0 Pseudorca carassidens False killer whale 4.35 14.3 Tursiops truncatus (Atlantic) Bottlenose dolphin 2.74 9.0...

  20. 9 CFR 3.104 - Space requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...'s dolphin 1.52 5.0 Delphinapterus leucas Beluga whale 4.27 14.0 Monodon monoceros Narwhale 3.96 13.0... 18.0 Grampus griseus Risso's dolphin 3.66 12.0 Orcinus orca Killer whale 7.32 24.0 Pseudorca carassidens False killer whale 4.35 14.3 Tursiops truncatus (Atlantic) Bottlenose dolphin 2.74 9.0...

  1. 9 CFR 3.104 - Space requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...'s dolphin 1.52 5.0 Delphinapterus leucas Beluga whale 4.27 14.0 Monodon monoceros Narwhale 3.96 13.0... 18.0 Grampus griseus Risso's dolphin 3.66 12.0 Orcinus orca Killer whale 7.32 24.0 Pseudorca carassidens False killer whale 4.35 14.3 Tursiops truncatus (Atlantic) Bottlenose dolphin 2.74 9.0...

  2. 9 CFR 3.104 - Space requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...'s dolphin 1.52 5.0 Delphinapterus leucas Beluga whale 4.27 14.0 Monodon monoceros Narwhale 3.96 13.0... 18.0 Grampus griseus Risso's dolphin 3.66 12.0 Orcinus orca Killer whale 7.32 24.0 Pseudorca carassidens False killer whale 4.35 14.3 Tursiops truncatus (Atlantic) Bottlenose dolphin 2.74 9.0...

  3. Protease-catalysed Direct Asymmetric Mannich Reaction in Organic Solvent

    NASA Astrophysics Data System (ADS)

    Xue, Yang; Li, Ling-Po; He, Yan-Hong; Guan, Zhi

    2012-10-01

    We reported the first enzyme-catalysed, direct, three-component asymmetric Mannich reaction using protease type XIV from Streptomyces griseus (SGP) in acetonitrile. Yields of up to 92% with enantioselectivities of up to 88% e.e. and diastereoselectivities of up to 92:8 (syn:anti) were achieved under the optimised conditions. This enzyme's catalytic promiscuity expands the application of this biocatalyst and provides a potential alternative method for asymmetric Mannich reactions.

  4. A Branch Point of Streptomyces Sulfur Amino Acid Metabolism Controls the Production of Albomycin

    PubMed Central

    Kulkarni, Aditya; Zeng, Yu; Zhou, Wei; Van Lanen, Steven; Zhang, Weiwen

    2015-01-01

    Albomycin (ABM), also known as grisein, is a sulfur-containing metabolite produced by Streptomyces griseus ATCC 700974. Genes predicted to be involved in the biosynthesis of ABM and ABM-like molecules are found in the genomes of other actinomycetes. ABM has potent antibacterial activity, and as a result, many attempts have been made to develop ABM into a drug since the last century. Although the productivity of S. griseus can be increased with random mutagenesis methods, understanding of Streptomyces sulfur amino acid (SAA) metabolism, which supplies a precursor for ABM biosynthesis, could lead to improved and stable production. We previously characterized the gene cluster (abm) in the genome-sequenced S. griseus strain and proposed that the sulfur atom of ABM is derived from either cysteine (Cys) or homocysteine (Hcy). The gene product, AbmD, appears to be an important link between primary and secondary sulfur metabolic pathways. Here, we show that propargylglycine or iron supplementation in growth media increased ABM production by significantly changing the relative concentrations of intracellular Cys and Hcy. An SAA metabolic network of S. griseus was constructed. Pathways toward increasing Hcy were shown to positively impact ABM production. The abmD gene and five genes that increased the Hcy/Cys ratio were assembled downstream of hrdBp promoter sequences and integrated into the chromosome for overexpression. The ABM titer of one engineered strain, SCAK3, in a chemically defined medium was consistently improved to levels ∼400% of the wild type. Finally, we analyzed the production and growth of SCAK3 in shake flasks for further process development. PMID:26519385

  5. The use of pronase enhances sensitivity of the PAP method in the detection of intracytoplasmic immunoglobulins.

    PubMed

    Pileri, S; Serra, L; Martinelli, G

    1980-01-01

    Application of immunocytochemistry to formalin-fixed, paraffin-embedded material tends to provide capricious results, even when employing the unlabelled antibody peroxidase-antiperoxidase (PAP) method. This study shows that treatment of tissue sections with pronase, a protease isolated from a strain of Streptomyces griseus, prior to performance of the PAP procedure greatly enhances its sensitivity. The optimum conditions for use of this enzyme in detecting intracellular immunoglobulins are given. PMID:6160845

  6. Protease-catalysed direct asymmetric Mannich reaction in organic solvent.

    PubMed

    Xue, Yang; Li, Ling-Po; He, Yan-Hong; Guan, Zhi

    2012-01-01

    We reported the first enzyme-catalysed, direct, three-component asymmetric Mannich reaction using protease type XIV from Streptomyces griseus (SGP) in acetonitrile. Yields of up to 92% with enantioselectivities of up to 88% e.e. and diastereoselectivities of up to 92:8 (syn:anti) were achieved under the optimised conditions. This enzyme's catalytic promiscuity expands the application of this biocatalyst and provides a potential alternative method for asymmetric Mannich reactions. PMID:23094136

  7. Protease-catalysed Direct Asymmetric Mannich Reaction in Organic Solvent

    PubMed Central

    Xue, Yang; Li, Ling-Po; He, Yan-Hong; Guan, Zhi

    2012-01-01

    We reported the first enzyme-catalysed, direct, three-component asymmetric Mannich reaction using protease type XIV from Streptomyces griseus (SGP) in acetonitrile. Yields of up to 92% with enantioselectivities of up to 88% e.e. and diastereoselectivities of up to 92:8 (syn:anti) were achieved under the optimised conditions. This enzyme's catalytic promiscuity expands the application of this biocatalyst and provides a potential alternative method for asymmetric Mannich reactions. PMID:23094136

  8. A Branch Point of Streptomyces Sulfur Amino Acid Metabolism Controls the Production of Albomycin.

    PubMed

    Kulkarni, Aditya; Zeng, Yu; Zhou, Wei; Van Lanen, Steven; Zhang, Weiwen; Chen, Shawn

    2016-01-01

    Albomycin (ABM), also known as grisein, is a sulfur-containing metabolite produced by Streptomyces griseus ATCC 700974. Genes predicted to be involved in the biosynthesis of ABM and ABM-like molecules are found in the genomes of other actinomycetes. ABM has potent antibacterial activity, and as a result, many attempts have been made to develop ABM into a drug since the last century. Although the productivity of S. griseus can be increased with random mutagenesis methods, understanding of Streptomyces sulfur amino acid (SAA) metabolism, which supplies a precursor for ABM biosynthesis, could lead to improved and stable production. We previously characterized the gene cluster (abm) in the genome-sequenced S. griseus strain and proposed that the sulfur atom of ABM is derived from either cysteine (Cys) or homocysteine (Hcy). The gene product, AbmD, appears to be an important link between primary and secondary sulfur metabolic pathways. Here, we show that propargylglycine or iron supplementation in growth media increased ABM production by significantly changing the relative concentrations of intracellular Cys and Hcy. An SAA metabolic network of S. griseus was constructed. Pathways toward increasing Hcy were shown to positively impact ABM production. The abmD gene and five genes that increased the Hcy/Cys ratio were assembled downstream of hrdBp promoter sequences and integrated into the chromosome for overexpression. The ABM titer of one engineered strain, SCAK3, in a chemically defined medium was consistently improved to levels ∼400% of the wild type. Finally, we analyzed the production and growth of SCAK3 in shake flasks for further process development. PMID:26519385

  9. The chromomycin CmmA acetyltransferase: a membrane-bound enzyme as a tool for increasing structural diversity of the antitumour mithramycin.

    PubMed

    García, Beatriz; González-Sabín, Javier; Menéndez, Nuria; Braña, Alfredo F; Núñez, Luz Elena; Morís, Francisco; Salas, José A; Méndez, Carmen

    2011-03-01

    Mithramycin and chromomycin A(3) are two structurally related antitumour compounds, which differ in the glycosylation profiles and functional group substitutions of the sugars. Chromomycin contains two acetyl groups, which are incorporated during the biosynthesis by the acetyltransferase CmmA in Streptomyces griseus ssp. griseus. A bioconversion strategy using an engineered S. griseus strain generated seven novel acetylated mithramycins. The newly formed compounds were purified and characterized by MS and NMR. These new compounds differ from their parental compounds in the presence of one, two or three acetyl groups, attached at 3E, 4E and/or 4D positions. All new mithramycin analogues showed antitumour activity at micromolar of lower concentrations. Some of the compounds showed improved activities against glioblastoma or pancreas tumour cells. The CmmA acetyltransferase was located in the cell membrane and was shown to accept several acyl-CoA substrates. All these results highlight the potential of CmmA as a tool to create structural diversity in these antitumour compounds. PMID:21342468

  10. Ain't No Neuroscience Mountain High Enough: Experiences of a Neurogardener.

    PubMed

    Abdullah, Jafri Malin

    2015-01-01

    16 years have passed since the idea was mooted in 1999 by five neurosurgeons in the corridors of Hotel Perdana, Kota Bharu. They were Dato' Dr Johari Siregar Bin Adnan, Dato' Professor Dr Ahmad Zubaidi Abdul Latif , Dr Azmin Kass Bin Rosman, Dato' Dr Mohammed Saffari Bin Mohammed Haspani and Professor Dato' Dr Jafri Malin Abdullah. They initiated the beginning of the first programme in Neurosurgery in Malaysia. The rest is history. PMID:26715890

  11. Pleiotropic role of the Sco1/SenC family copper chaperone in the physiology of Streptomyces

    PubMed Central

    Fujimoto, Masahiro; Yamada, Akio; Kurosawa, Junpei; Kawata, Akihiro; Beppu, Teruhiko; Takano, Hideaki; Ueda, Kenji

    2012-01-01

    Summary Antibiotic production and cell differentiation in Streptomyces is stimulated by micromolar levels of Cu2+. Here, we knocked out the Sco1/SenC family copper chaperone (ScoC) encoded in the conserved gene cluster ‘sco’ (the S treptomycescopper utilization) in Streptomyces coelicolor A3(2) and S. griseus. It is known that the Sco1/SenC family incorporates Cu2+ into the active centre of cytochrome oxidase (cox). The knockout caused a marked delay in antibiotic production and aerial mycelium formation on solid medium, temporal pH decline in glucose‐containing liquid medium, and significant reduction of cox activity in S. coelicolor. The scoC mutant produced two‐ to threefold higher cellular mass of the wild type exhibiting a marked cox activity in liquid medium supplied with 10 µM CuSO4, suggesting that ScoC is involved in not only the construction but also the deactivation of cox. The scoC mutant was defective in the monoamine oxidase activity responsible for cell aggregation and sedimentation. These features were similarly observed with regard to the scoC mutant of S. griseus. The scoC mutant of S. griseus was also defective in the extracellular activity oxidizing N,N′‐dimethyl‐p‐phenylenediamine sulfate. Addition of 10 µM CuSO4 repressed the activity of the conserved promoter preceding scoA and caused phenylalanine auxotrophy in some Streptomyces spp. probably because of the repression of pheA; pheA encodes prephenate dehydratase, which is located at the 3′ terminus of the putative operon structure. Overall, the evidence indicates that Sco is crucial for the utilization of copper under a low‐copper condition and for the activation of the multiple Cu2+‐containing oxidases that play divergent roles in the complex physiology of Streptomyces. PMID:22117562

  12. Phylogenetic revision of Minyomerus Horn, 1876 sec. Jansen & Franz, 2015 (Coleoptera, Curculionidae) using taxonomic concept annotations and alignments

    PubMed Central

    Jansen, M. Andrew; Franz, Nico M.

    2015-01-01

    Abstract This contribution adopts the taxonomic concept annotation and alignment approach. Accordingly, and where indicated, previous and newly inferred meanings of taxonomic names are individuated according to one specific source. Articulations among these concepts and pairwise, logically consistent alignments of original and revisionary classifications are also provided, in addition to conventional nomenclatural provenance information. A phylogenetic revision of the broad-nosed weevil genera Minyomerus Horn, 1876 sec. O’Brien & Wibmer (1982), and Piscatopus Sleeper, 1960 sec. O’Brien & Wibmer (1982) (Curculionidae [non-focal]: Entiminae [non-focal]: Tanymecini [non-focal]) is presented. Prior to this study, Minyomerus sec. O’Brien & Wibmer (1982) contained seven species, whereas the monotypic Piscatopus sec. O’Brien & Wibmer (1982) was comprised solely of Piscatopus griseus Sleeper, 1960 sec. O’Brien & Wibmer (1982). We thoroughly redescribe these recognized species-level entities and furthermore describe ten species as new to science: Minyomerus bulbifrons sec. Jansen & Franz (2015) (henceforth: [JF2015]), sp. n., Minyomerus aeriballux [JF2015], sp. n., Minyomerus cracens [JF2015], sp. n., Minyomerus gravivultus [JF2015], sp. n., Minyomerus imberbus [JF2015], sp. n., Minyomerus reburrus [JF2015], sp. n., Minyomerus politus [JF2015], sp. n., Minyomerus puticulatus [JF2015], sp. n., Minyomerus rutellirostris [JF2015], sp. n., and Minyomerus trisetosus [JF2015], sp. n. A cladistic analysis using 46 morphological characters of 22 terminal taxa (5/17 outgroup/ingroup) yielded a single most-parsimonious cladogram (L = 82, CI = 65, RI = 82). The analysis strongly supports the monophyly of Minyomerus [JF2015] with eight unreversed synapomorphies, and places Piscatopus griseus sec. O’Brien & Wibmer (1982) within the genus as sister to Minyomerus rutellirostris [JF2015]. Accordingly, Piscatopus sec. Sleeper (1960), syn. n. is changed to junior synonymy of

  13. Phylogenetic revision of Minyomerus Horn, 1876 sec. Jansen & Franz, 2015 (Coleoptera, Curculionidae) using taxonomic concept annotations and alignments.

    PubMed

    Jansen, M Andrew; Franz, Nico M

    2015-01-01

    This contribution adopts the taxonomic concept annotation and alignment approach. Accordingly, and where indicated, previous and newly inferred meanings of taxonomic names are individuated according to one specific source. Articulations among these concepts and pairwise, logically consistent alignments of original and revisionary classifications are also provided, in addition to conventional nomenclatural provenance information. A phylogenetic revision of the broad-nosed weevil genera Minyomerus Horn, 1876 sec. O'Brien & Wibmer (1982), and Piscatopus Sleeper, 1960 sec. O'Brien & Wibmer (1982) (Curculionidae [non-focal]: Entiminae [non-focal]: Tanymecini [non-focal]) is presented. Prior to this study, Minyomerus sec. O'Brien & Wibmer (1982) contained seven species, whereas the monotypic Piscatopus sec. O'Brien & Wibmer (1982) was comprised solely of Piscatopus griseus Sleeper, 1960 sec. O'Brien & Wibmer (1982). We thoroughly redescribe these recognized species-level entities and furthermore describe ten species as new to science: Minyomerus bulbifrons sec. Jansen & Franz (2015) (henceforth: [JF2015]), sp. n., Minyomerus aeriballux [JF2015], sp. n., Minyomerus cracens [JF2015], sp. n., Minyomerus gravivultus [JF2015], sp. n., Minyomerus imberbus [JF2015], sp. n., Minyomerus reburrus [JF2015], sp. n., Minyomerus politus [JF2015], sp. n., Minyomerus puticulatus [JF2015], sp. n., Minyomerus rutellirostris [JF2015], sp. n., and Minyomerus trisetosus [JF2015], sp. n. A cladistic analysis using 46 morphological characters of 22 terminal taxa (5/17 outgroup/ingroup) yielded a single most-parsimonious cladogram (L = 82, CI = 65, RI = 82). The analysis strongly supports the monophyly of Minyomerus [JF2015] with eight unreversed synapomorphies, and places Piscatopus griseus sec. O'Brien & Wibmer (1982) within the genus as sister to Minyomerus rutellirostris [JF2015]. Accordingly, Piscatopus sec. Sleeper (1960), syn. n. is changed to junior synonymy of Minyomerus [JF2015], and

  14. Agnonistic behavior in short-billed dowitchers feeding on a patchy resource

    USGS Publications Warehouse

    Mallory, E.P.; Schneider, D.C.

    1979-01-01

    In this paper we describe an instance of unusual, agonistic behavior in a flock of migrant Short-billed Dowitchers (Limnodromus griseus) . We compare this behavior to that of other flocks feeding at the same time at other locations in the same estuary and then present evidence suggesting that this behavior resulted from the patchy distribution of the probable foraging resource of this flock, eggs of the horseshoe crab (Limulus polyphemus). We propose that an extremely patchy resource has increased the agonistic behavior within the flock by increasing the variation in foraging success among individuals.

  15. The use of marine reserves in evaluating the dive fishery for the warty sea cucumber, Parastichopus parvimensis in California, U.S.A

    USGS Publications Warehouse

    Schroeder, S.C.; Reed, D.C.; Kushner, D.J.; Estes, J.A.; Ono, D.S.

    2001-01-01

    In this paper we describe an instance of unusual, agonistic behavior in a flock of migrant Short-billed Dowitchers (Limnodromus griseus) . We compare this behavior to that of other flocks feeding at the same time at other locations in the same estuary and then present evidence suggesting that this behavior resulted from the patchy distribution of the probable foraging resource of this flock, eggs of the horseshoe crab (Limulus polyphemus). We propose that an extremely patchy resource has increased the agonistic behavior within the flock by increasing the variation in foraging success among individuals.

  16. Secretion of Elastinolytic Enzymes and Their Propeptides by Pseudomonas aeruginosa

    PubMed Central

    Braun, Peter; de Groot, Arjan; Bitter, Wilbert; Tommassen, Jan

    1998-01-01

    Elastase of Pseudomonas aeruginosa is synthesized as a preproenzyme. The signal sequence is cleaved off during transport across the inner membrane and, in the periplasm, proelastase is further processed. We demonstrate that the propeptide and the mature elastase are both secreted but that the propeptide is degraded extracellularly. In addition, reduction of the extracellular proteolytic activity led to the accumulation of unprocessed forms of LasA and LasD in the extracellular medium, which shows that these enzymes are secreted in association with their propeptides. Furthermore, a hitherto undefined protein with homology to a Streptomyces griseus aminopeptidase accumulated under these conditions. PMID:9642203

  17. Secretion of elastinolytic enzymes and their propeptides by Pseudomonas aeruginosa.

    PubMed

    Braun, P; de Groot, A; Bitter, W; Tommassen, J

    1998-07-01

    Elastase of Pseudomonas aeruginosa is synthesized as a preproenzyme. The signal sequence is cleaved off during transport across the inner membrane and, in the periplasm, proelastase is further processed. We demonstrate that the propeptide and the mature elastase are both secreted but that the propeptide is degraded extracellularly. In addition, reduction of the extracellular proteolytic activity led to the accumulation of unprocessed forms of LasA and LasD in the extracellular medium, which shows that these enzymes are secreted in association with their propeptides. Furthermore, a hitherto undefined protein with homology to a Streptomyces griseus aminopeptidase accumulated under these conditions. PMID:9642203

  18. Population Genetic Structure of a Widespread Bat-Pollinated Columnar Cactus.

    PubMed

    Bustamante, Enriquena; Búrquez, Alberto; Scheinvar, Enrique; Eguiarte, Luis Enrique

    2016-01-01

    Bats are the main pollinators and seed dispersers of Stenocereus thurberi, a xenogamous columnar cactus of northwestern Mexico and a good model to illustrate spatial dynamics of gene flow in long-lived species. Previous studies in this cactus showed differences among populations in the type and abundance of pollinators, and in the timing of flowering and fruiting. In this study we analyzed genetic variability and population differentiation among populations. We used three primers of ISSR to analyze within and among populations genetic variation from eight widely separated populations of S. thurberi in Sonora, Mexico. Sixty-six out of 99 of the ISSR bands (P = 66.7%) were polymorphic. Total heterozygosity for all populations sampled revealed high genetic diversity (Hsp = 0.207, HBT = 0.224). The AMOVA showed that most of the genetic variation was within populations (80.5%). At the species level, estimates of population differentiation, θ = 0.175 and θB = 0.194, indicated moderate gene flow among populations. The absence of a significant correlation between genetic and geographic distances indicated little isolation by geographic distance. The large genetic variation and diversity found in S. thurberi is consistent with its open reproductive system and the high mobility of bats, a major pollinator. However, small changes in number or kind of pollinators and seed dispersal agents, in the directionality of migratory routes, and/or in the timing of flowering and fruiting among populations, can critically affect gene flow dynamics. PMID:27015281

  19. Microbial populations and activities in the rhizoplane of rock-weathering desert plants. I. Root colonization and weathering of igneous rocks.

    PubMed

    Puente, M E; Bashan, Y; Li, C Y; Lebsky, V K

    2004-09-01

    Dense layers of bacteria and fungi in the rhizoplane of three species of cactus (Pachycereus pringlei, Stenocereus thurberi, Opuntia cholla) and a wild fig tree (Ficus palmeri) growing in rocks devoid of soil were revealed by bright-field and fluorescence microscopy and field emission scanning electron microscopy. These desert plants are responsible for rock weathering in an ancient lava flow at La Purisima-San Isidro and in sedimentary rock in the Sierra de La Paz, both in Baja California Sur, Mexico. The dominant bacterial groups colonizing the rhizoplane were fluorescent pseudomonads and bacilli. Seven of these bacterial species were identified by the 16S rRNA molecular method. Unidentified fungal and actimomycete species were also present. Some of the root-colonizing microorganisms fixed in vitro N(2), produced volatile and non-volatile organic acids that subsequently reduced the pH of the rock medium in which the bacteria grew, and significantly dissolved insoluble phosphates, extrusive igneous rock, marble, and limestone. The bacteria were able to release significant amounts of useful minerals, such as P, K, Mg, Mn, Fe, Cu, and Zn from the rocks and were thermo-tolerant, halo-tolerant, and drought-tolerant. The microbial community survived in the rhizoplane of cacti during the annual 10-month dry season. This study indicates that rhizoplane bacteria on cacti roots in rock may be involved in chemical weathering in hot, subtropical deserts. PMID:15375735

  20. Population Genetic Structure of a Widespread Bat-Pollinated Columnar Cactus

    PubMed Central

    Bustamante, Enriquena; Búrquez, Alberto; Scheinvar, Enrique; Eguiarte, Luis Enrique

    2016-01-01

    Bats are the main pollinators and seed dispersers of Stenocereus thurberi, a xenogamous columnar cactus of northwestern Mexico and a good model to illustrate spatial dynamics of gene flow in long-lived species. Previous studies in this cactus showed differences among populations in the type and abundance of pollinators, and in the timing of flowering and fruiting. In this study we analyzed genetic variability and population differentiation among populations. We used three primers of ISSR to analyze within and among populations genetic variation from eight widely separated populations of S. thurberi in Sonora, Mexico. Sixty-six out of 99 of the ISSR bands (P = 66.7%) were polymorphic. Total heterozygosity for all populations sampled revealed high genetic diversity (Hsp = 0.207, HBT = 0.224). The AMOVA showed that most of the genetic variation was within populations (80.5%). At the species level, estimates of population differentiation, θ = 0.175 and θB = 0.194, indicated moderate gene flow among populations. The absence of a significant correlation between genetic and geographic distances indicated little isolation by geographic distance. The large genetic variation and diversity found in S. thurberi is consistent with its open reproductive system and the high mobility of bats, a major pollinator. However, small changes in number or kind of pollinators and seed dispersal agents, in the directionality of migratory routes, and/or in the timing of flowering and fruiting among populations, can critically affect gene flow dynamics. PMID:27015281

  1. Holocene vegetation and climate in the Puerto Blanco Mountains, southwestern Arizona

    NASA Astrophysics Data System (ADS)

    Van Devender, Thomas R.

    1987-01-01

    Plant macrofossils from 21 pack rat ( Neotoma sp.) middens at 535-605 m from the Puerto Blanco Mountains, southwestern Arizona, provide and excellent history of vegetation and climate for the last 14, 120 yr B.P. in the Sonoran Desert. A late Wisconsin juniper-Joshua tree woodland gave way to a transitional early Holocene desertscrub with sparse Juniperus californica (California juniper) by 10,540 yr B.P. Important Sonoran Desert plants including Carnegiea gigantea (saguaro) and Encelia farinosa (brittle bush) were dominants. Riparian trees such as Acacia greggii (catclaw acacia), Prosopis velutina (velvet mesquite), and Cerdicium floridum (blue palo verde) grew on dry, south-facing slopes in a middle Holocene Sonoran desertscrub in a warm, wet summer climate with frequent winter freezes. Modern subtropical Sonoran desertscrub formed about 4000 yr B.P. as summer rainfall and winter freezes declined. Cercidium microphyllum (foothills palo verde), Sapium biloculare (Mexican jumping bean), Olneya tesota (ironwood) and Stenocereus thurberi (organ pipe cactus) became dominant as riparian trees retreated to wash habitats. The inferences of a latest Wisconsin/early Holocene summer monsoonal maximum by J. E. Kutzbach (1983), Modeling of Holocene climates. In "Late-Quaternary Environments of the United States," Vol. 2, "The Holocene" (H. E. Wright, Ed.), pp. 271-277. Univ. of Minnesota Press, Minneapolis) are not supported for the Southwest. Apparently the persistence of late Wisconsin circulation patterns offset any increases in insolation.

  2. CO{sub 2} exchange environmental productivity indices, and productivity of agaves and cacti under current and elevated atmospheric CO{sub 2} concentrations. Final report

    SciTech Connect

    Nobel, P.S.

    1994-12-31

    The research described in the proposal investigated net CO{sub 2} uptake and biomass accumulation for an extremely productive CAM plant, the prickly pear cactus Opuntia ficus-indica, under conditions of elevated CO{sub 2} concentrations for relatively long periods. The influences of soil water status, air temperature, and the photosynthetic photon flux (PPF) on net CO{sub 2} uptake over 24-h periods were evaluated to enable predictions to be made based on an Environmental Productivity Index (EPI). Specifically, EPI predicts the fraction of maximal daily net CO{sub 2} uptake based on prevailing environmental conditions. It is the product of indices for temperature, soil water, and intercepted PPF, each of which range from 0.00 when that index factor completely inhibits net CO{sub 2} uptake to 1.00 when no limitation occurs. For instance, the Water Index is 1.00 under wet conditions and decreases to 0.00 during prolonged drought. Although the major emphasis of the research was on net C0{sub 2} uptake and the resulting biomass production for O. ficus-indica, effects of elevated CO{sub 2} concentrations on root: shoot ratios and on the activities of the two carboxylating enzymes were also investigated. Moreover, experiments were also done on other CAM plants, including Agave deserti, Agave salmiana, and Hylocereus undatus, and Stenocereus queretaroensis.

  3. CO{sub 2} exchange, environmental productivity indices, and productivity of Agaves and Cacti under current and elevated atmospheric CO{sub 2} concentrations. Terminal report

    SciTech Connect

    1995-06-01

    The research described in the proposal investigated net CO{sub 2} uptake and biomass accumulation for an extremely productive CAM plant, the prickly pear cactus Opuntia ficus-indica, under conditions of elevated CO{sub 2} concentrations for relatively long periods. The influences of soil water status, air temperature, and the photosynthetic photon flux (PPF) on net CO{sub 2} uptake over 24-h periods were evaluated to enable predictions to be made based on an Environmental Productivity Index (EPI). Specifically, EPI predicts the fraction of maximal daily net CO{sub 2} uptake based on prevailing environmental conditions. It is the product of indices for temperature, soil water, and intercepted PPF, each of which range from 0.00 when that index factor completely inhibits net CO{sub 2} uptake to 1.00 when no limitation occurs. For instance, the Water Index is 1.00 under wet conditions and decreases to 0.00 during prolonged drought. Although the major emphasis of the research was on net CO{sub 2} uptake and the resulting biomass production for O. ficus-indica, effects of elevated CO{sub 2} concentrations on root: shoot ratios and on the activities of the two carboxylating enzymes were also investigated. Moreover, experiments were also done on other CAM plants, including Agave deserti, Agave salmiana, and Hylocereus undatus, and Stenocereus queretaroensis.

  4. Bacterial degradation of natural and synthetic rubber.

    PubMed

    Bode, H B; Kerkhoff, K; Jendrossek, D

    2001-01-01

    The degradation of natural rubber (NR), synthetic poly(cis-1,4-isoprene) (SR), and cross-linked NR (latex gloves) by Gram-positive and Gram-negative bacteria was analyzed by weight loss, gel permeation chromatography, and determination of the protein content. Weight losses of 11-18% and an increase in protein up to 850 microg/mL after incubation of Nocardia sp. DSMZ43191, Streptomyces coelicolor, Streptomyces griseus, bacterial isolate 18a, Acinetobacter calcoaceticus, and Xanthomonas sp. with latex gloves as a carbon source indicated degradation of the polymer. An increase of protein up to 1250 microg/mL was obtained upon incubation of the bacteria with SR. No or only little weight losses and no increase in the protein content were found for nondegrading control strains such as Streptomyces lividans and Streptomyces exfoliatus and for mutants of degrading strains of S. coelicolor and S. griseus, which have been identified by their inability to produce clearing zones on opaque latex agar. Measurement of the average molecular weight of synthetic rubber before and after degradation showed a time-dependent shift to lower values for the degrading strains. Diketone derivates of oligo(cis-1,4-isoprene) were identified as metabolites of rubber degradation. An oxidative degradation pathway of poly(cis-1,4-isoprene) to acetyl-coenzymeA and propionyl-coenzymeA by beta-oxidation is suggested for bacterial degradation of isoprene rubber. PMID:11749186

  5. Diversity among Streptomyces Strains Causing Potato Scab

    PubMed Central

    Doering-Saad, Christiane; Kämpfer, Peter; Manulis, Shulamit; Kritzman, Giora; Schneider, Jörg; Zakrzewska-Czerwinska, Jolanta; Schrempf, Hildgund; Barash, Isaac

    1992-01-01

    Eighty Streptomyces isolates, including 35 potato scab-inducing strains and 12 reference strains of Streptomyces scabies, were physiologically characterized by a total of 329 miniaturized tests. Overall similarities of all strains were determined by numerical taxonomy, with the unweighted average linkage (UPGMA) algorithm and simple matching (Ssm) and Jaccard (Sj) coefficients used as measures for similarity. Three cluster groups (A to C) were defined at a similarity level of 80.1% (Ssm); these groups contained 14 clusters and 24 unclustered strains defined at a similarity level of 86.5% (Ssm). Cluster group A contained strains phenotypically related to S. griseus or S. exfoliatus, whereas cluster group B contained strains which were phenotypically related to S. violaceus or S. rochei. The majority of the pathogenic isolates and reference strains were assigned to S. violaceus (57%) and S. griseus (22%). A DNA probe derived from the rRNA operon of S. coelicolor IMET 40271 was used to detect restriction fragment length polymorphisms (RELPs) among 40 pathogenic and nonpathogenic Streptomyces isolates. Southern blots revealed a high degree of diversity among the pathogenic strains tested. No significant correlation between numerical classification and RFLP grouping of Streptomyces strains could be revealed. The results obtained suggest that RFLP data are of minor importance in classification of Streptomyces species and that genes for pathogenicity determinants are spread among different Streptomyces species by mobilizable elements. Images PMID:16348823

  6. Molecular assessment of the phylogeny and biogeography of a recently diversified endemic group of South American canids (Mammalia: Carnivora: Canidae)

    PubMed Central

    Tchaicka, Ligia; de Freitas, Thales Renato Ochotorena; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E.; Wayne, Robert K.; Eizirik, Eduardo

    2016-01-01

    Abstract To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus. PMID:27560989

  7. Trophic Relationships and Habitat Preferences of Delphinids from the Southeastern Brazilian Coast Determined by Carbon and Nitrogen Stable Isotope Composition

    PubMed Central

    Bisi, Tatiana Lemos; Dorneles, Paulo Renato; Lailson-Brito, José; Lepoint, Gilles; Azevedo, Alexandre de Freitas; Flach, Leonardo; Malm, Olaf; Das, Krishna

    2013-01-01

    To investigate the foraging habitats of delphinids in southeastern Brazil, we analyzed stable carbon (δ13C) and nitrogen (δ15N) isotopes in muscle samples of the following 10 delphinid species: Sotalia guianensis, Stenella frontalis, Tursiops truncatus, Steno bredanensis, Pseudorca crassidens, Delphinus sp., Lagenodelphis hosei, Stenella attenuata, Stenella longirostris and Grampus griseus. We also compared the δ13C and δ15N values among four populations of S. guianensis. Variation in carbon isotope results from coast to ocean indicated that there was a significant decrease in δ13C values from estuarine dolphins to oceanic species. S. guianensis from Guanabara Bay had the highest mean δ13C value, while oceanic species showed significantly lower δ13C values. The highest δ15N values were observed for P. crassidens and T. truncatus, suggesting that these species occupy the highest trophic position among the delphinids studied here. The oceanic species S. attenuata, G. griseus and L. hosei had the lowest δ15N values. Stable isotope analysis showed that the three populations of S. guianensis in coastal bays had different δ13C values, but similar δ15N results. Guiana dolphins from Sepetiba and Ilha Grande bays had different foraging habitat, with specimens from Ilha Grande showing more negative δ13C values. This study provides further information on the feeding ecology of delphinids occurring in southeastern Brazil, with evidence of distinctive foraging habitats and the occupation of different ecological niches by these species in the study area. PMID:24358155

  8. Genome-wide Distribution of AdpA, a Global Regulator for Secondary Metabolism and Morphological Differentiation in Streptomyces, Revealed the Extent and Complexity of the AdpA Regulatory Network

    PubMed Central

    Higo, Akiyoshi; Hara, Hirofumi; Horinouchi, Sueharu; Ohnishi, Yasuo

    2012-01-01

    AdpA is a global transcriptional activator triggering morphological differentiation and secondary metabolism in Streptomyces griseus. AdpA influences the expression of >1000 genes; however, the overall picture of the AdpA regulon remains obscure. Here, we took snapshots of the distribution of AdpA across the chromosome in living S. griseus cells using chromatin immunoprecipitation/chromatin affinity precipitation-seq analysis. In both liquid and solid cultures, AdpA bound to >1200 similar sites, which were located on not only in putative regulatory regions (65%), but also in regions (35%) that appeared not to affect transcription. Transcriptome analysis indicated that ∼40% of the AdpA-binding sites in putative regulatory regions were involved in gene regulation. AdpA was indicated to act as a transcriptional repressor as well as an activator. Expression profiles of AdpA-target genes were very different between liquid and solid cultures, despite their similar AdpA-binding profiles. We concluded that AdpA directly controls >500 genes in cooperation with other regulatory proteins. A comprehensive competitive gel mobility shift assay of AdpA with 304 selected AdpA-binding sites revealed several unique characteristics of the DNA-binding property of AdpA. This study provides the first experimental insight into the extent of the AdpA regulon, indicating that many genes are under the direct control of AdpA. PMID:22449632

  9. Identification and characterization of the afsR homologue regulatory gene from Streptomyces peucetius ATCC 27952.

    PubMed

    Parajuli, Niranjan; Viet, Hung Trinh; Ishida, Kenji; Tong, Hang Thi; Lee, Hei Chan; Liou, Kwangkyoung; Sohng, Jae Kyung

    2005-01-01

    We have isolated an afsR homologue, called afsR-p, through genome analysis of Streptomyces peucetius ATCC 27952. AfsR-p shares 60% sequence identity with AfsR from Streptomyces coelicolor A3 (2). afsR-p was expressed under the control of the ermE* promoter in its hosts S. peucetius, Streptomyces lividans TK 24, Streptomyces clavuligerus and Streptomyces griseus. We observed overproduction of doxorubicin (4-fold) in S. peucetius, gamma-actinorhodin (2.6-fold) in S. lividans, clavulanic acid (1.5-fold) in S. clavuligerus and streptomycin (slight) in S. griseus. Overproduction was due to expression of the gene in these strains as compared to the wild-type strains harboring the vector only. Comparative study of the expression of afsR-p revealed that regulatory networking in Streptomyces is not uniform. We speculate that phosphorylated AfsR-p becomes bound to the promoter region of afsS. The latter activates other regulatory genes, including pathway regulatory genes, and induces the production of secondary metabolites including antibiotics. We identified specific conserved amino acids and exploited them for the isolation of the partial sequence of the afsR homologue from S. clavuligerus and Streptomyces achromogens (rubradirin producer). Such findings provide additional evidence for the presence of a serine/threonine and tyrosine kinase-dependent global regulatory network in Streptomyces. PMID:15921897

  10. Molecular assessment of the phylogeny and biogeography of a recently diversified endemic group of South American canids (Mammalia: Carnivora: Canidae).

    PubMed

    Tchaicka, Ligia; Freitas, Thales Renato Ochotorena de; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E; Wayne, Robert K; Eizirik, Eduardo

    2016-01-01

    To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus. PMID:27560989

  11. The Level of AdpA Directly Affects Expression of Developmental Genes in Streptomyces coelicolor ▿ †

    PubMed Central

    Wolański, Marcin; Donczew, Rafał; Kois-Ostrowska, Agnieszka; Masiewicz, Paweł; Jakimowicz, Dagmara; Zakrzewska-Czerwińska, Jolanta

    2011-01-01

    AdpA is a key regulator of morphological differentiation in Streptomyces. In contrast to Streptomyces griseus, relatively little is known about AdpA protein functions in Streptomyces coelicolor. Here, we report for the first time the translation accumulation profile of the S. coelicolor adpA (adpASc) gene; the level of S. coelicolor AdpA (AdpASc) increased, reaching a maximum in the early stage of aerial mycelium formation (after 36 h), and remained relatively stable for the next several hours (48 to 60 h), and then the signal intensity decreased considerably. AdpASc specifically binds the adpASc promoter region in vitro and in vivo, suggesting that its expression is autoregulated; surprisingly, in contrast to S. griseus, the protein presumably acts as a transcriptional activator. We also demonstrate a direct influence of AdpASc on the expression of several genes whose products play key roles in the differentiation of S. coelicolor: STI, a protease inhibitor; RamR, an atypical response regulator that itself activates expression of the genes for a small modified peptide that is required for aerial growth; and ClpP1, an ATP-dependent protease. The diverse influence of AdpASc protein on the expression of the analyzed genes presumably results mainly from different affinities of AdpASc protein to individual promoters. PMID:21926228

  12. Molecular assessment of the phylogeny and biogeography of a recently diversified endemic group of South American canids (Mammalia: Carnivora: Canidae).

    PubMed

    Tchaicka, Ligia; Freitas, Thales Renato Ochotorena de; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E; Wayne, Robert K; Eizirik, Eduardo

    2016-07-25

    To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus. PMID:27459260

  13. Molecular and Functional Analyses of the Gene (eshA) Encoding the 52-Kilodalton Protein of Streptomyces coelicolor A3(2) Required for Antibiotic Production

    PubMed Central

    Kawamoto, Shinichi; Watanabe, Masakatsu; Saito, Natsumi; Hesketh, Andrew; Vachalova, Katerina; Matsubara, Keiko; Ochi, Kozo

    2001-01-01

    Analysis of proteins recovered in the S100 precipitate fraction of Streptomyces griseus after ultracentrifugation led to the identification of a 52-kDa protein which is produced during the late growth phase. The gene (eshA) which codes for this protein was cloned from S. griseus, and then its homologue was cloned from Streptomyces coelicolor A3(2). The protein was deduced to be 471 amino acids in length. The protein EshA is characterized by a central region that shows homology to the eukaryotic-type cyclic nucleotide-binding domains. Significant homology was also found to MMPI in Mycobacterium leprae, a major antigenic protein to humans. The eshA gene mapped near the chromosome end and was not essential for viability, as demonstrated by gene disruption experiments, but its disruption resulted in the abolishment of an antibiotic (actinorhodin but not undecylprodigiosin) production. Aerial mycelium was produced as abundantly as by the parent strain. Expression analysis of the EshA protein by Western blotting revealed that EshA is present only in late-growth-phase cells. The eshA gene was transcribed just preceding intracellular accumulation of the EshA protein, as determined by S1 nuclease protection, indicating that EshA expression is regulated at the transcription level. The expression of EshA was unaffected by introduction of the relA mutation, which blocks ppGpp synthesis. PMID:11567001

  14. Trophic relationships and habitat preferences of delphinids from the southeastern Brazilian coast determined by carbon and nitrogen stable isotope composition.

    PubMed

    Bisi, Tatiana Lemos; Dorneles, Paulo Renato; Lailson-Brito, José; Lepoint, Gilles; Azevedo, Alexandre de Freitas; Flach, Leonardo; Malm, Olaf; Das, Krishna

    2013-01-01

    To investigate the foraging habitats of delphinids in southeastern Brazil, we analyzed stable carbon (δ(13)C) and nitrogen (δ(15)N) isotopes in muscle samples of the following 10 delphinid species: Sotalia guianensis, Stenella frontalis, Tursiops truncatus, Steno bredanensis, Pseudorca crassidens, Delphinus sp., Lagenodelphis hosei, Stenella attenuata, Stenella longirostris and Grampus griseus. We also compared the δ(13)C and δ(15)N values among four populations of S. guianensis. Variation in carbon isotope results from coast to ocean indicated that there was a significant decrease in δ(13)C values from estuarine dolphins to oceanic species. S. guianensis from Guanabara Bay had the highest mean δ(13)C value, while oceanic species showed significantly lower δ(13)C values. The highest δ(15)N values were observed for P. crassidens and T. truncatus, suggesting that these species occupy the highest trophic position among the delphinids studied here. The oceanic species S. attenuata, G. griseus and L. hosei had the lowest δ(15)N values. Stable isotope analysis showed that the three populations of S. guianensis in coastal bays had different δ(13)C values, but similar δ(15)N results. Guiana dolphins from Sepetiba and Ilha Grande bays had different foraging habitat, with specimens from Ilha Grande showing more negative δ(13)C values. This study provides further information on the feeding ecology of delphinids occurring in southeastern Brazil, with evidence of distinctive foraging habitats and the occupation of different ecological niches by these species in the study area. PMID:24358155

  15. Transglutaminase from Streptomyces mobaraensis is activated by an endogenous metalloprotease.

    PubMed

    Zotzel, J; Keller, P; Fuchsbauer, H-L

    2003-08-01

    Streptomyces mobaraensis secretes a Ca2+-independent transglutaminase (TGase) that is activated by removing an N-terminal peptide from a precursor protein during submerged culture in a complex medium [Pasternack, R., Dorsch, S., Otterbach, J. T., Robenek, I. R., Wolf, S. & Fuchsbauer, H.-L. (1998) Eur. J. Biochem. 257, 570-576]. However, an activating protease could not be identified, probably because of the presence of a 14-kDa protein (P14) belonging to the Streptomyces subtilisin inhibitor family. In contrast, if the microorganism was allowed to grow on a minimal medium, several soluble proteases were extracted, among them the TGase-activating protease (TAMEP). TAMEP was purified by sequential chromatography on DEAE- and Arg-Sepharose and used to determine the cleavage site of TGase. It was clearly shown that the peptide bond between Phe(-4) and Ser(-5) was hydrolyzed, indicating that at least one additional peptidase is necessary to complete TGase processing, even if TAMEP cleavage was sufficient to obtain total activity. Sequence analysis from the N-terminus of TAMEP revealed the close relationship to a zinc endo-protease from S. griseus. The S. griseus protease differs from other members of the M4 protease family, such as thermolysin, in that it may be inhibited by the Streptomyces subtilisin inhibitor. P14 likewise inhibits TAMEP in approximately equimolar concentrations, suggesting its important role in regulating TGase activity. PMID:12869197

  16. Effects of natural and artificial selection on survival of columnar cacti seedlings: the role of adaptation to xeric and mesic environments

    PubMed Central

    Guillén, Susana; Terrazas, Teresa; Casas, Alejandro

    2015-01-01

    Escontria chiotilla, Polaskia chichipe, and Stenocereus pruinosus are species of Mexican columnar cacti that are economically important because of their edible fruits. These species are managed by gathering fruits from the wild, silvicultural management in agroforestry systems, and cultivation in home gardens. Previous studies reported that artificial selection favored individuals that produced larger fruits, which indirectly led to the production of larger seeds and seedlings, with possible effects on survival. We hypothesized that seedlings from managed populations would be larger but more susceptible to xeric conditions than those from wild populations. We evaluated the effects of artificial and natural selection on seedling survival of the three species in wild and managed populations, which were managed with low and high intensity, respectively. We tested seedling performance in gradients of shade (0, 40, and 80%) and humidity (low and high). A GLM of seedling survival showed significant differences among species, shade, and humidity treatments, with each species having environmental requirements associated with their particular adaptations. High humidity decreased seedling survival of all species, and high solar radiation decreased survival of S. pruinosus and P. chichipe. The effect of management type was significant only in S. pruinosus. Significant differences in the initial growth of seedlings among species were detected with ANOVA. In optimal conditions, the hypocotyl and the cotyledons decreased in size and the epicotyl grew, whereas under stress, these structures remained unchanged. The optimum conditions of shade and humidity varied among species and management types. The seedlings of S. pruinosus were the largest and the most susceptible, but in all species, seedlings from managed populations were more susceptible to environmental conditions. Thus, artificial selection influenced the susceptibility of these cacti to xeric environments. PMID

  17. Genomics of Ecological Adaptation in Cactophilic Drosophila

    PubMed Central

    Guillén, Yolanda; Rius, Núria; Delprat, Alejandra; Williford, Anna; Muyas, Francesc; Puig, Marta; Casillas, Sònia; Ràmia, Miquel; Egea, Raquel; Negre, Barbara; Mir, Gisela; Camps, Jordi; Moncunill, Valentí; Ruiz-Ruano, Francisco J.; Cabrero, Josefa; de Lima, Leonardo G.; Dias, Guilherme B.; Ruiz, Jeronimo C.; Kapusta, Aurélie; Garcia-Mas, Jordi; Gut, Marta; Gut, Ivo G.; Torrents, David; Camacho, Juan P.; Kuhn, Gustavo C.S.; Feschotte, Cédric; Clark, Andrew G.; Betrán, Esther; Barbadilla, Antonio; Ruiz, Alfredo

    2015-01-01

    Cactophilic Drosophila species provide a valuable model to study gene–environment interactions and ecological adaptation. Drosophila buzzatii and Drosophila mojavensis are two cactophilic species that belong to the repleta group, but have very different geographical distributions and primary host plants. To investigate the genomic basis of ecological adaptation, we sequenced the genome and developmental transcriptome of D. buzzatii and compared its gene content with that of D. mojavensis and two other noncactophilic Drosophila species in the same subgenus. The newly sequenced D. buzzatii genome (161.5 Mb) comprises 826 scaffolds (>3 kb) and contains 13,657 annotated protein-coding genes. Using RNA sequencing data of five life-stages we found expression of 15,026 genes, 80% protein-coding genes, and 20% noncoding RNA genes. In total, we detected 1,294 genes putatively under positive selection. Interestingly, among genes under positive selection in the D. mojavensis lineage, there is an excess of genes involved in metabolism of heterocyclic compounds that are abundant in Stenocereus cacti and toxic to nonresident Drosophila species. We found 117 orphan genes in the shared D. buzzatii–D. mojavensis lineage. In addition, gene duplication analysis identified lineage-specific expanded families with functional annotations associated with proteolysis, zinc ion binding, chitin binding, sensory perception, ethanol tolerance, immunity, physiology, and reproduction. In summary, we identified genetic signatures of adaptation in the shared D. buzzatii–D. mojavensis lineage, and in the two separate D. buzzatii and D. mojavensis lineages. Many of the novel lineage-specific genomic features are promising candidates for explaining the adaptation of these species to their distinct ecological niches. PMID:25552534

  18. Determinate primary root growth as an adaptation to aridity in Cactaceae: towards an understanding of the evolution and genetic control of the trait

    PubMed Central

    Shishkova, Svetlana; Las Peñas, María Laura; Napsucialy-Mendivil, Selene; Matvienko, Marta; Kozik, Alex; Montiel, Jesús; Patiño, Anallely; Dubrovsky, Joseph G.

    2013-01-01

    Background and Aims Species of Cactaceae are well adapted to arid habitats. Determinate growth of the primary root, which involves early and complete root apical meristem (RAM) exhaustion and differentiation of cells at the root tip, has been reported for some Cactoideae species as a root adaptation to aridity. In this study, the primary root growth patterns of Cactaceae taxa from diverse habitats are classified as being determinate or indeterminate, and the molecular mechanisms underlying RAM maintenance in Cactaceae are explored. Genes that were induced in the primary root of Stenocereus gummosus before RAM exhaustion are identified. Methods Primary root growth was analysed in Cactaceae seedlings cultivated in vertically oriented Petri dishes. Differentially expressed transcripts were identified after reverse northern blots of clones from a suppression subtractive hybridization cDNA library. Key Results All species analysed from six tribes of the Cactoideae subfamily that inhabit arid and semi-arid regions exhibited determinate primary root growth. However, species from the Hylocereeae tribe, which inhabit mesic regions, exhibited mostly indeterminate primary root growth. Preliminary results suggest that seedlings of members of the Opuntioideae subfamily have mostly determinate primary root growth, whereas those of the Maihuenioideae and Pereskioideae subfamilies have mostly indeterminate primary root growth. Seven selected transcripts encoding homologues of heat stress transcription factor B4, histone deacetylase, fibrillarin, phosphoethanolamine methyltransferase, cytochrome P450 and gibberellin-regulated protein were upregulated in S. gummosus root tips during the initial growth phase. Conclusions Primary root growth in Cactoideae species matches their environment. The data imply that determinate growth of the primary root became fixed after separation of the Cactiodeae/Opuntioideae and Maihuenioideae/Pereskioideae lineages, and that the genetic regulation of

  19. Inhibition of alcohol dehydrogenase after 2-propanol exposure in different geographic races of Drosophila mojavensis: lack of evidence for selection at the Adh-2 locus.

    PubMed

    Pfeiler, Edward; Reed, Laura K; Markow, Therese A

    2005-03-15

    High frequencies of the fast allele of alcohol dehydrogenase-2 (Adh-2F) are found in populations of Drosophila mojavensis that inhabit the Baja California peninsula (race BII) whereas the slow allele (Adh-2S) predominates at most other localities within the species' geographic range. Race BII flies utilize necrotic tissue of pitaya agria cactus (Stenocereus gummosus) which contains high levels of 2-propanol, whereas flies from most other localities utilize different cactus hosts in which 2-propanol levels are low. To test if 2-propanol acts as a selective force on Adh-2 genotype, or whether some other yet undetermined genetic factor is responsible, mature males of D. mojavensis lines derived from the Grand Canyon (race A) and Santa Catalina Island (race C), each with individuals homozygous for Adh-2F and Adh-2S, were exposed to 2-propanol for 24 h and ADH-2 specific activity was then determined on each genotype. Flies from five other localities homozygous for either the fast or slow allele also were examined. Results for all reported races of D. mojavensis were obtained. 2-propanol exposure inhibited ADH-2 specific activity in both genotypes from all localities, but inhibition was significantly less in two populations of race BII flies homozygous for Adh-2F. When F/F and S/S genotypes in flies from the same locality were compared, both genotypes showed high 2-propanol inhibition that was not statistically different, indicating that the F/F genotype alone does not provide a benefit against the inhibitory effects of 2-propanol. ADH-1 activity in female ovaries was inhibited less by 2-propanol than ADH-2. These results do not support the hypothesis that 2-propanol acts as a selective factor favoring the Adh-2F allele. PMID:15726639

  20. Western gray squirrel (Rodentia: Sciuridae): a primary reservoir host of Borrelia burgdorferi in Californian oak woodlands?

    PubMed

    Lane, Robert S; Mun, Jeomhee; Eisen, Rebecca J; Eisen, Lars

    2005-05-01

    In California, dense woodlands have been recognized as important biotopes where humans are exposed to the nymphal stage of the western blacklegged tick, Ixodes pacificus Cooley & Kohls, the primary vector of the Lyme disease spirochete Borrelia burgdorferi sensu stricto (s.s.), in the far-western United States. To identify the principal reservoir host(s) of this spirochete, and of closely related spirochetes in the B. burgdorferi sensu lato (s.l.) complex, in dense woodlands in Mendocino County, California, approximately 50 species of birds and mammals, including wood rats and kangaroo rats, were evaluated as potential hosts for vector ticks and borreliae in 2002 and 2003. Although polymerase chain reaction (PCR) and sequencing analyses revealed that many vertebrate species had been exposed to one or more members of the B. burgdorferi s.l. spirochetal complex, only the western gray squirrel, Sciurus griseus, fulfilled the major criteria for a reservoir host of B. burgdorferi s.s. Ear-punch biopsies from eight of 10 squirrels collected from five separate woodlands were PCR-positive for B. burgdorferi s.s., 47% of I. pacificus larvae (n = 64) and 31% of nymphs (n = 49) removed from squirrels contained B. burgdorferi s.l., and the engorgement status of I. pacificus larvae was associated positively with acquisition of spirochetes. Overall, 83 and 100% of the amplicons sequenced from PCR-positive I. pacificus larvae and nymphs, respectively, were identified as B. burgdorferi s.s, Among the five remaining positive I. pacificus larvae, three contained B. bissettii and two had uncharacterized B. burgdorferi s.l. Borrelia burgdorferi s.s. was detected in one of five larvae and zero of two nymphs of the Pacific Coast tick, Dermacentor occidentalis Marx, that likewise had been removed from squirrels. The rickettsial agent of human anaplasmosis, Anaplasma phagocytophilum, was detected in the blood or ear biopsies of two squirrels and in one (1.6%) of 64 I. pacificus larvae and

  1. Kinetics of leaping primates: influence of substrate orientation and compliance.

    PubMed

    Demes, B; Jungers, W L; Gross, T S; Fleagle, J G

    1995-04-01

    Our current knowledge about the forces leapers generate and absorb is very limited and based exclusively on rigid force platform measurements. In their natural environments, however, leapers take off and land on branches and tree trunks, and these may be compliant. We evaluated the influence of substrate properties on leaping kinetics in prosimian leapers by using a combined field and laboratory approach. Tree sway and the timing of takeoffs relative to the movements of trees were documented for animals under natural conditions in Madagascar. Field data collected on three species (Indri indri, Propithecus diadema, Propithecus verreauxi) indicate that in the majority of takeoffs, the substrate sways and the animals takeoff before the elastic rebound of the substrate. This implies that force is "wasted" to deform supports. Takeoff and landing forces were measured in an experimental setting with a compliant force pole at the Duke University Primate Center. Forces were recorded for 2 Propithecus verreauxi and 3 Hapalemur griseus. Peak takeoff forces were 9.6 (P. verreauxi) and 10.3 (H. griseus) times body weight, whereas peak landing forces were 6.7 (P. verreauxi) and 8.4 (H. griseus) times body weight. As part of the impulse generated does not translate into leaping distance but is used to deform the pole, greater effort is required to reach a given target substrate, and, consequently, takeoff forces are high. The landing forces, on the other hand, are damped by the pole/substrate yield that increases the time available for deceleration. Our results contrast with previous studies of leaping forces recorded with rigid platform measuring systems that usually report higher landing than takeoff forces. We conclude that 1) Leapers generate and are exposed to exceptionally high locomotory forces. The takeoff forces are higher than the landing forces when using compliant supports, indicating that the takeoff rather than the landing may be critical in interpreting leaping

  2. Winter status of White-eyed Vireos in northeastern Louisiana

    USGS Publications Warehouse

    Somershoe, S.G.; Twedt, D.J.

    2005-01-01

    In December 2004, February 2005, and June 2005, we recaptured a White-eyed Vireo (Vireo griseus) that was banded on 19 May 2004 at the same location on the Tensas River National Wildlife Refuge, Madison Parish, LA. This is the first documented permanent resident White-eyed Vireo outside of resident populations known from Florida and southern Texas. This individual appears to be resident near the northern limit of the winter range for the species. Although White-eyed Vireos are uncommon in northeastern Louisiana during winter, we detected other White-eyed Vireos during line transect surveys and banding during winters 2003-2004 and 2004-2005. The lack of research and observation of winter birds in northern Louisiana and the secretive and inconspicuous behavior of White-eyed Vireos in winter may have led to an underestimation of abundance at the northern limits of their winter range.

  3. First record of interspecific breeding of Least Bell's Vireo and White-eyed Vireo

    USGS Publications Warehouse

    Blundell, Melissa A.; Kus, Barbara E.

    2011-01-01

    We provide the first known documentation of a male Least Bell's Vireo (Vireo bellii pusillus) breeding with a female White-eyed Vireo (V. griseus) and the first report of a White-eyed Vireo breeding in California at the San Luis Rey River, Oceanside, San Diego County. We discovered the pair building a nest on 12 May 2010. The female laid four eggs, and the pair successfully raised and fledged four nestlings. We collected DNA samples from each nestling and the female during the nestling stage and banded them with a numbered federal leg band for future identification. We obtained detailed nest measurements after fledging and monitored the territory for further nesting attempts. No additional nesting attempts were detected.

  4. Common procedures in hedgehogs, prairie dogs, exotic rodents, and companion marsupials.

    PubMed

    Johnson-Delaney, Cathy A

    2006-05-01

    Nondomesticated species are commonly being kept as companion animals. These include the African pygmy hedgehog (Atelerix albi-ventris), the North American black-tailed prairie dog (Cynomys lu-dovicianus), and exotic rodents such as the degu (Octodon degus)and duprasi or fat-tailed gerbil (Pachyuromys duprasi). Common companion marsupials include the sugar glider (Petaurus breviceps),Bennett's or Tammar (Dama) wallabies (Macropus rufogriseus rufo-griseus and Macropus eugenii, respectively), the Brazilian or South American gray short-tailed opossum (Monodelphis domestica), and the North American Virginia opossum (Didelphis virginiana). Although many of these animals are now bred domestically and are fairly docile when human-raised, they are essentially wild animals and hence have strong instincts to hide illness and pain. PMID:16759954

  5. Residency of Reef Fish During Pile Driving Within a Shallow Pierside Environment.

    PubMed

    Iafrate, Joseph D; Watwood, Stephanie L; Reyier, Eric A; Gilchrest, Matthew; Crocker, Steven E

    2016-01-01

    The potential effects of pile driving on fish populations and commercial fisheries have received significant attention given the prevalence of construction occurring in coastal habitats throughout the world. In this study, we used acoustic telemetry to assess the movement and survival of free-ranging reef fish in Port Canaveral, FL, in response to 35 days of pile driving at an existing wharf complex. The site fidelity and behavior of 15 sheepshead (Archosargus probatocephalus) and 10 gray snapper (Lutjanus griseus) were determined before, during, and after pile driving. No obvious signs of mortality or injury to tagged fish were evident from the data. There was a significant decline in the residency index for mangrove snapper at the construction wharf after pile driving compared with the baseline, although this may be influenced by natural movements of this species in the study area rather than a direct response to pile driving. PMID:26610995

  6. Chitinase activity on amorphous chitin thin films: a quartz crystal microbalance with dissipation monitoring and atomic force microscopy study.

    PubMed

    Wang, Chao; Kittle, Joshua D; Qian, Chen; Roman, Maren; Esker, Alan R

    2013-08-12

    Chitinases are widely distributed in nature and have wide-ranging pharmaceutical and biotechnological applications. This work highlights a real-time and label-free method to assay Chitinase activity via a quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM). The chitin substrate was prepared by spincoating a trimethylsilyl chitin solution onto a silica substrate, followed by regeneration to amorphous chitin (RChi). The QCM-D and AFM results clearly showed that the hydrolysis rate of RChi films increased as Chitinase (from Streptomyces griseus) concentrations increased, and the optimal temperature and pH for Chitinase activity were around 37 °C and 6-8, respectively. The Chitinase showed greater activity on chitin substrates, having a high degree of acetylation, than on chitosan substrates, having a low degree of acetylation. PMID:23822524

  7. Purification and Characterization of a Keratinolytic Serine Proteinase from Streptomyces albidoflavus

    PubMed Central

    Bressollier, Philippe; Letourneau, François; Urdaci, Maria; Verneuil, Bernard

    1999-01-01

    Streptomyces strain K1-02, which was identified as a strain of Streptomyces albidoflavus, secreted at least six extracellular proteases when it was cultured on feather meal-based medium. The major keratinolytic serine proteinase was purified to homogeneity by a two-step procedure. This enzyme had a molecular weight of 18,000 and was optimally active at pH values ranging from 6 to 9.5 and at temperatures ranging from 40 to 70°C. Its sensitivity to protease inhibitors, its specificity on synthetic substrates, and its remarkably high level of NH2-terminal sequence homology with Streptomyces griseus protease B (SGPB) showed that the new enzyme, designated SAKase, was homologous to SGPB. We tested the activity of SAKase with soluble and fibrous substrates (elastin, keratin, and type I collagen) and found that it was very specific for keratinous substrates compared to SGPB and proteinase K. PMID:10347045

  8. Divergent effects of desferrioxamine on bacterial growth and characteristics.

    PubMed

    Eto, Daisei; Watanabe, Kenta; Saeki, Hisafumi; Oinuma, Ken-ichi; Otani, Ko-ichi; Nobukuni, Megumi; Shiratori-Takano, Hatsumi; Takano, Hideaki; Beppu, Teruhiko; Ueda, Kenji

    2013-04-01

    Desferrioxamines (DF's) are siderophores produced by some groups of bacteria. Previously, we discovered that DFE, produced by Streptomyces griseus, induced divergent developmental phenotypes in various Streptomyces isolates. In this study, we isolated bacteria whose phenotype was affected by the presence of 0.1 mM DFB from soil samples, and studied their phylogenetic position via 16 S rRNA gene-based analysis. Isolates belonging to Microbacterium grew only in the presence of DFB in the medium. DFB promoted growth of some isolates, while significantly inhibiting that of other divergent bacteria. Different groups of isolates were affected, not because of growth-related changes, but because of changes in the colony morphology based on possible stimulation of motility. An isolate affiliated with Janthinobacterium was stimulated for violacein production as well as for pilus formation. The wide and divergent effects of DFB suggest that availability of siderophores significantly affect the structure of microbial community. PMID:23232933

  9. Morphologic characteristics of pulmonary macrophages in cetaceans: particular reference to pulmonary intravascular macrophages as a newly identified type.

    PubMed

    Kawashima, M; Kuwamura, M; Takeya, M; Yamate, J

    2004-11-01

    We examined the morphologic characteristics of pulmonary macrophages in 42 specimens of Odontoceti (Globicephala macrorhynchus, Grampus griseus, Tursiops truncatus, Stenella attenuata, Stenella coeruleoalba, Berardius bairdii), using light and electron microscopes as well as immunohistochemistry with SRA-E5. SRA-E5-positive alveolar macrophages and pulmonary interstitial macrophages contained graphitic soots, indicating the clearance of airborne, aspirated foreign bodies. Pulmonary intravascular macrophages (PIMs), positive with SRA-E5, were present within pulmonary capillaries, attaching to applied endothelial cells by cell junctions. They showed cytoplasmic tubular structures of micropinocytosis vermiformis and erythrophagocytosis, indicating their contributory role in the clearance of blood-borne particles. The uptake of pathogens by PIMs may be associated with the inducement of acute lung injury, especially bacterial infectious pneumonia. This study revealed for the first time the presence of PIMs in cetaceans. PMID:15557077

  10. Retinal projections in two crocodilian species, Caiman crocodilus and Crocodylus niloticus.

    PubMed

    Derobert, Y; Médina, M; Rio, J P; Ward, R; Repérant, J; Marchand, M J; Miceli, D

    1999-08-01

    The retinal projections of Caiman crocodilus and Crocodylus niloticus were investigated by means of the orthograde axonal transport of either rhodamine beta-isothiocyanate or tritiated proline. In these two species, each tracer revealed contralateral retinal projections to three hypothalamic regions (subventricular gray matter, nucleus suprachiasmaticus, and area optica hypothalami lateralis), five thalamic regions (nuclei ovalis, dorsolateralis anterior, ventrolateralis and ventrobasalis, and lateral geniculate complex, of which six subcomponents can be distinguished), six pretectal regions (nuclei posterodorsalis, lentiformis mesencephali, griseus tectalis, geniculatus pretectalis, area optica commissurae posterior and area optica pretectalis lateroventralis), six outermost layers of the optic tectum, and the nucleus opticus tegmenti. Weak ipsilateral retinal projections have been observed in two hypothalamic nuclei and in the nucleus opticus tegmenti. Comparative analysis with other data show that the contralateral retinal projections of crocodiles are considerably more reptilian than avian. Moreover, crocodiles share with birds an extremely poor contingent of ipsilateral retinal projections. PMID:10424875

  11. Shorebird diet and size selection of nereid polychaetes in South Carolina coastal diked wetlands

    USGS Publications Warehouse

    Weber, Louise M.; Haig, Susan M.

    1997-01-01

    Coastal wetlands that are diked and managed may supplement declining natural habitat for migrating shorebirds (Charadriiformes). However, data on shorebird diet in these diked wetlands are scarce. We examined shorebird diet and prey size selection in brackish diked wetlands at the Yawkey Center on South Island, South Carolina, USA. Gut contents of seven Lesser Yellowlegs (Tringa flavipes) and seven Short-billed Dowitchers (Limnodromus griseus) were examined. The most common items in gut contents were mandibles of the nereid polychaete, Laeonereis culveri, followed by insects. L. culveri eaten by Short-billed Dowitchers were significantly larger than those eaten by Lesser Yellowlegs. This difference may be related to differences in bill length and feeding tactics. We make suggestions on how to maintain high numbers of L. culveri in diked wetlands, but more research on the timing of colonization by invertebrates is needed in shorebird conservation efforts.

  12. Identification of a cryptic type III polyketide synthase (1,3,6,8-tetrahydroxynaphthalene synthase) from Streptomyces peucetius ATCC 27952.

    PubMed

    Ghimire, Gopal Prasad; Oh, Tae-Jin; Liou, Kwangkyoung; Sohng, Jae Kyung

    2008-10-31

    We identified a 1,134-bp putative type III polyketide synthase from the sequence analysis of Streptomyces peucetius ATCC 27952, named Sp-RppA, which is characterized as 1,3,6,8-tetrahydroxynaphthalene synthase and shares 33% identity with SCO1206 from S. coelicolor A3(2) and 32% identity with RppA from S. griseus. The 1,3,6,8-tetrahydroxynaphthalene synthase is known to catalyze the sequential decarboxylative condensation, intramolecular cyclization, and aromatization of an oligoketide derived from five units of malonyl-CoA to give 1,3,6,8-tetrahydroxynaphthalene, which spontaneously oxidizes to form 2,5,7-trihydroxy-1,4-naphthoquinone (flaviolin). In this study, we report the in vivo expression and in vitro synthesis of flaviolin from purified gene product (Sp-RppA). PMID:18612244

  13. Engineering Protein Allostery: 1.05 Å Resolution Structure and Enzymatic Properties of a Na[superscript +]-activated Trypsin

    SciTech Connect

    Page, Michael J.; Carrell, Christopher J.; Di Cera, Enrico

    2008-05-28

    Some trypsin-like proteases are endowed with Na{sup +}-dependent allosteric enhancement of catalytic activity, but this important mechanism has been difficult to engineer in other members of the family. Replacement of 19 amino acids in Streptomyces griseus trypsin targeting the active site and the Na{sup +}-binding site were found necessary to generate efficient Na{sup +} activation. Remarkably, this property was linked to the acquisition of a new substrate selectivity profile similar to that of factor Xa, a Na{sup -} activated protease involved in blood coagulation. The X-ray crystal structure of the mutant trypsin solved to 1.05 {angstrom} resolution defines the engineered Na{sup +} site and active site loops in unprecedented detail. The results demonstrate that trypsin can be engineered into an efficient allosteric protease, and that Na+ activation is interwoven with substrate selectivity in the trypsin scaffold.

  14. Distribution of Cd and As in organs and tissues of four marine mammal species stranded along the Italian coasts.

    PubMed

    Bellante, Antonio; Sprovieri, Mario; Buscaino, Giuseppa; Buffa, Gaspare; Di Stefano, Vincenzo; Manta, Daniela Salvagio; Barra, Marco; Filiciotto, Francesco; Bonanno, Angelo; Mazzola, Salvatore

    2012-09-01

    Concentrations of Cd and As were determined in organs and tissues (muscle, heart, kidney, lung and liver) of four cetacean species (Stenella coeruleoalba, Truncatus truncatus, Grampus griseus and Ziphius cavirostris) stranded along the Italian coasts during the period 2000-2009. Significant differences were found between Cd concentrations in the different analysed tissues. Particularly, the kidney shows the highest concentrations of Cd in all analysed specimens, followed by the liver. No systematic or statistically significant difference in As concentrations was found in the analysed tissues. Considerable differences of Cd and As values in samples from different geographical areas (Sicily Channel, Adriatic Sea and Tyrrhenian Sea) were found, with the highest values measured in samples from the Sicily Channel. This basically suggests that anthropogenic and natural sources significantly affect Cd and As content in cetaceans. PMID:22797766

  15. Kinetics of Methyl t-Butyl Ether Cometabolism at Low Concentrations by Pure Cultures of Butane-Degrading Bacteria

    PubMed Central

    Liu, Catherine Y.; Speitel, Gerald E.; Georgiou, George

    2001-01-01

    Butane-oxidizing Arthrobacter (ATCC 27778) bacteria were shown to degrade low concentrations of methyl t-butyl ether (MTBE; range, 100 to 800 μg/liter) with an apparent half-saturation concentration (Ks) of 2.14 mg/liter and a maximum substrate utilization rate (kc) of 0.43 mg/mg of total suspended solids per day. Arthrobacter bacteria demonstrated MTBE degradation activity when grown on butane but not when grown on glucose, butanol, or tryptose phosphate broth. The presence of butane, tert-butyl alcohol, or acetylene had a negative impact on the MTBE degradation rate. Neither Methylosinus trichosporium OB3b nor Streptomyces griseus was able to cometabolize MTBE. PMID:11319100

  16. Behavioral Response of Reef Fish and Green Sea Turtles to Midfrequency Sonar.

    PubMed

    Watwood, Stephanie L; Iafrate, Joseph D; Reyier, Eric A; Redfoot, William E

    2016-01-01

    There is growing concern over the potential effects of high-intensity sonar on wild fish populations and commercial fisheries. Acoustic telemetry was employed to measure the movements of free-ranging reef fish and sea turtles in Port Canaveral, FL, in response to routine submarine sonar testing. Twenty-five sheepshead (Archosargus probatocephalus), 28 gray snapper (Lutjanus griseus), and 29 green sea turtles (Chelonia mydas) were tagged, with movements monitored for a period of up to 4 months using an array of passive acoustic receivers. Baseline residency was examined for fish and sea turtles before, during, and after the test event. No mortality of tagged fish or sea turtles was evident from the sonar test event. There was a significant increase in the daily residency index for both sheepshead and gray snapper at the testing wharf subsequent to the event. No broad-scale movement from the study site was observed during or immediately after the test. PMID:26611089

  17. Challenges in the Synthesis of a Unique Mono-Carboxylic Acid Antibiotic (+)-Zincophorin

    PubMed Central

    Song, Zhenlei; Lohse, Andrew G.; Hsung, Richard P.

    2009-01-01

    (+)-Zincophorin, also referred to as M144255 or griseochellin, is a polyoxygenated ionophoric antibiotic that was isolated from Streptomyces griseus in 1984. It possesses strong in vivo activity against Gram-positive bacteria and Clostridium coelchii. Its methyl ester was reported in a patent as having strong inhibitory properties against influenza WSN/virus with reduced toxicity for the host cell. Its ability to strongly bind with Zn2+, which is also present in its X-ray structure, is the basis for its name. Over the last two decades, (+)-zincophorin h as attracted an impressive array of synthetic efforts including Danishefsky's first total synthesis along with two recent elegant total syntheses reported by Cossy and Miyashita as well as our own formal total synthesis. This Account provides a comparison of the different synthetic efforts on this novel mono-carboxylic acid antibiotic and documents its interesting isolation, structure determination, and biological activities. PMID:19642422

  18. Interaction between aspergilli and streptomycetes in the soil of potted indoor plants: a preliminary report (contribution to the epidemiology of human aspergillosis).

    PubMed

    Staib, F; Mishra, S K; Blisse, A

    1980-02-29

    The soil of potted ornamental plants as a reservoir for Aspergillus species pathogenic for man is of epidemiological and ecological interest. Isolation of A. niger as the sole hyphomycete from the soil of potted African violets (Saintpaulia ionantha, Gesneriaceae), prompted us to look for A. inger on the surface of the roots of this plant. Small pieces of the roots were inoculated in the nutrient-free agar-gel with and without antibiotics. On the antibiotic-free gel, a dense growth of Streptomyces griseus was consistently observed around the root pieces. But the gel fortified with antibiotics showed pure growth of only A. niger. One of the two strains of S. ariseus isolated from the African violet, showed inhibitory effect against a number of fungi including A. niger but the other strain had no effect on this fungus. The possible influence of streptomycetes on the occurrence of aspergilli in the soil of potted ornamental plants is discussed. PMID:6769046

  19. Flotation of cadmium-loaded biomass.

    PubMed

    Matis, K A; Zouboulis, A I

    1994-07-01

    Biosorption of heavy metal ions such as Cd(2+) by dead biomass has been recognized as a potential alternative to existing removal technologies applied to wastewater treatment. Two bacterial strains were studied in the laboratory, streptomyces griseus and S. clavuligerus, an industrial by-product. Both washed and unwashed samples were examined. Foam flotation proposed in this work as the separation state following biosorption. Effective biomass separation was conducted in the presence of a frother, ethanol. The pH of the solution was a crucial parameter for flotation and also for metal binding. Other basic parameters of flotation examined were the initial cadmium concentration in the dilute aqueous solution and the quantity of biomass used. A study of zeta-potential measurements of the actinomycetes was carried out under the conditions used in the separation; surface tension was also measured. These provided useful information on the process. PMID:18618752

  20. Molecular characterization of a gene encoding extracellular serine protease isolated from a subtilisin inhibitor-deficient mutant of Streptomyces albogriseolus S-3253.

    PubMed Central

    Taguchi, S; Odaka, A; Watanabe, Y; Momose, H

    1995-01-01

    An extracellular serine protease produced by a mutant, M1, derived from Streptomyces albogriseolus S-3253 that no longer produces a protease inhibitor (Streptomyces subtilisin inhibitor [SSI]) was isolated. A 20-kDa protein was purified by its affinity for SSI and designated SAM-P20. The amino acid sequence of the amino-terminal region of SAM-P20 revealed high homology with the sequences of Streptomyces griseus proteases A and B, and the gene sequence confirmed the relationships. The sequence also revealed a putative amino acid signal sequence for SAM-P20 that apparently functioned to allow secretion of SAM-P20 from Escherichia coli carrying the recombinant gene. SAM-P20 produced by E. coli cells was shown to be sensitive to SSI inhibition. PMID:7887600

  1. [Structure and functions of bacterial proteinase precursors].

    PubMed

    Serkina, A V; Shevelev, A B; Chestukhina, G G

    2001-01-01

    The data on the precursors of bacterial proteases were generalized. The structure and special features of processing of the precursors of bacillary subtilisins, the alpha-lytic protease from Lysobacter enzymogenes and the related chymotrypsin-like proteases from Streptomyces griseus, and the metalloproteases from bacilli and Pseudomonas aeruginosa were discussed. The approaches to producing the precursors and the protease propeptides and to in vitro characterizing them were particularly analyzed. The following physiological functions of the propeptides within the protease precursors were considered probable: (a) inhibition of the proteases to protect the host cells from the proteolytic damage; (b) participation in the folding of the mature enzyme; and (c) providing for the protease interaction with the bacterial cell surveillance mechanisms, including protease translocation through the cell wall. PMID:11641907

  2. Purification, characterization cloning, and sequencing of metalloendopeptidase from Streptomyces septatus TH-2.

    PubMed

    Hatanaka, Tadashi; Yoshiko Uesugi, Jiro Arima; Iwabuchi, Masaki

    2005-02-15

    Streptomyces septatus TH-2 secretes a large amount of a protease when cultured on a medium containing K(2)HPO(4) and glucose. The enzyme was purified to homogeneity by a three-step procedure. This enzyme had a molecular mass of approximately 35kDa, and was particularly inhibited by EDTA and phosphoramidon. Its substrate specificity was investigated using novel fluorescence energy transfer combinatorial libraries. The protease was found to prefer Phe and Tyr at the P(1) position, a hydrophobic or basic residue at the P(2) position, and a basic or small residue at the P(3) position. Its gene was cloned and sequenced, and its deduced amino acid sequence contained an HEXXH consensus sequence for zinc binding, confirming that it encodes metalloendopeptidase. The primary structure of the enzyme showed 40 and 69% identities with that of thermolysin from Bacillus thermoproteolyticus and that of a metalloendopeptidase from Streptomyces griseus, respectively. PMID:15639229

  3. Peptide sequence information derived by pronase digestion and ammonium sulfate in-source decay matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

    PubMed

    Marzilli, L A; Golden, T R; Cotter, R J; Woods, A S

    2000-11-01

    We present the use of Pronase digestion and in-source decay in the presence of ammonium sulfate as complementary techniques to confirm the amino acid sequence of a peptide. Pronase, a commercial preparation from Streptomyces griseus, is a combination of proteolytic enzymes. It produces carboxypeptidase and aminopeptidase ladders using a single Pronase digestion and represents an inexpensive, nonspecific, and fast supplement to traditional sequencing enzymes. However, N-terminal peptidase activity appears dependent on the terminal amino acid residue. We also introduce the use of saturated ammonium sulfate as an "on-slide" sample additive to promote in-source fragmentation of peptides. Use of saturated ammonium sulfate resulted in a simple way to increase peptide backbone fragmentation and essentially produced either a cn or yn ion series. Together these techniques provide useful supplements to existing methods for peptide sequence information. PMID:11073263

  4. Inhibition of metalloendopeptidases by 2-mercaptoacetyl-dipeptides.

    PubMed

    Blumberg, S; Tauber, Z

    1983-10-17

    A series of 2-mercaptoacetyl-dipeptides, a potential group of metalloendopeptidase inhibitors, has been synthesized by coupling the N-hydroxysuccinimide ester of S-acetyl-2-mercaptoacetic acid with hydrophobic dipeptide methyl ester hydrochlorides, followed by hydrolysis with NaOH in aqueous methanol and acidification with HCl. Thus, the 2-mercaptoacetyl derivatives of L-phenylalanyl-L-leucine, L-leucyl-L-phenylalanine and L-leucyl-D-phenylalanine were prepared. The first two compounds inhibit effectively thermolysin from Bacillus thermoproteolyticus and a metalloendopeptidase isolated from Streptomyces griseus, with Ki values in the micromolar range or below. The third compound inhibits the two enzymes only poorly, showing the stereospecificity of the inhibition process. These inhibitors should provide a useful tool for the study of bacterial and mammalian metalloendopeptidases (or dipeptidyl carboxypeptidases) and for the assessment of their physiological role. PMID:6413206

  5. [The effect of enzymatic treatment using proteases on properties of persistent sodium current in CA1 pyramidal neurons of rat hippocampus].

    PubMed

    Lun'ko, O O; Isaiev, D S; Maxymiuk, O P; Kryshtal', O O; Isaieva, O V

    2014-01-01

    We investigated the effect of proteases, widely used for neuron isolation in electrophysiological studies, on the amplitude and kinetic characteristics of persistent sodium current (I(NaP)) in hippocampal CA1 pyramidal neurons. Properties of I(NaP) were studied on neurons isolated by mechanical treatment (control group) and by mechanical and enzymatic treatment using pronase E (from Streptomyces griseus) or protease type XXIII (from Aspergillus oryzae). We show that in neurons isolated with pronase E kinetic of activation and density of I(NaP) was unaltered. Enzymatic treatment with protease type XXIII did not alter I(NaP) activation but result in significant decrease in I(NaP) density. Our data indicates that enzymatic treatment using pronase E for neuron isolation is preferable for investigation of I(NaP). PMID:25097934

  6. Flotation of cadmium-loaded biomass

    SciTech Connect

    Matis, K.A.; Zouboulis, A.I. . Chemical Technology Div.)

    1994-07-01

    Biosorption of heavy metal ions such as Cd[sup 2+] by dead biomass has been recognized as a potential alternative to existing removal technologies applied to wastewater treatment. Two bacterial strains were studied in the laboratory, Streptomyces griseus and S. clavuligerus, an industrial by-product. Both washed and unwashed samples were examined. Foam flotation is proposed in this work as the separation stage following biosorption. Effective biomass separation was conducted in the presence of a frother, ethanol. The pH of the solution was a crucial parameter for flotation and also for metal binding. Other basic parameters of flotation examined were the initial cadmium concentration in the dilute aqueous solution and the quantity of biomass used. A study of [zeta]-potential measurements of the actinomycetes was carried out under the conditions used in the separation; surface tension was also measured. These provided useful information on the process.

  7. [Morphology of gametes in sea urchins from Peter the Great Bay, Sea of Japan].

    PubMed

    Drozdov, A L; Vinnikova, V V

    2010-01-01

    The fine structure of the gametes in six sea urchin species of the Sea of Japan was studied. The spermatozoons in Strongylocentrotus nudus, S. intermedius, Echinocardium cordatum, Scaphechinus mirabilis, Sc. grizeus and Echinarachnius parma are species-specific. The conical head and symmetrically disposed ring-shape mitochondrion are common to regular sea urchin sperm cells. S. nudus is characterized by the bulb-shaped head of the zoosperm; S. intermedius, by a bullet-shaped one. The zoosperm spearhead and small amount of postacrosome material are common to irregular sea urchins; the sperm width: length ratio varies for different species, with the highest for Sc. mirabilis. The zoosperm of Sc. griseus is characterized by two lipid drops in the cell center. Asymmetrical mitochondrion disposal is usual for E. parma. Actin filaments are found in the postacrosome material in the zoosperm of cordiform sea urchins. The differences in the fine structure of zoosperm in eurybiont species Ech. cordatum inhabiting the Sea of Japan and coastal areas of the Northeast Atlantic may bear record to the complex existence of species Ech. cordatum. The fine structure of zoosperm is unique for each of the studied families, Strongylocentrotidae, Scutellidae, and Loveniidae. The eggs of all the species are characterized by vitelline and tremelloid membranes. The vitelline membrane is formed by cytoplasm protrusions; the area between them is filled with fubrillary material. The tremelloid membrane is formed by fubrillary material associated with apical parts of microvilli of the vitelline membrane. The irregular sea urchins Sc. griseus, Sc. mirabilis and E. parma are characterized by chromatophores situated in the tremelloid membrane, with the highest abundance in Sc. mirabilis. PMID:20184121

  8. Intraguild Predation in Heteroptera: Effects of Density and Predator Identity on Dipteran Prey.

    PubMed

    Brahma, S; Sharma, D; Kundu, M; Saha, N; Saha, G K; Aditya, G

    2015-08-01

    In tropical freshwaters, different species of water bugs (Heteroptera) constitute a guild sharing similar prey resources including chironomid and mosquito larvae. Assuming possibilities of intraguild predation (IGP) among the constituent members, an attempt was made to evaluate the effects of prey and predator density on the mortality of mosquito and chironomid larvae (shared prey), using Laccotrephes griseus Guérin-Méneville (Hemiptera: Nepidae) and Ranatra filiformis Fabricius (Hemiptera: Nepidae) as IG predators and Anisops bouvieri Kirkaldy (Hemiptera: Notonectidae) as IG prey. The predation on mosquito and chironomid larvae varied with the density and combinations of the predators. When present as conspecific IG predators, L. griseus exhibited greater effect on the prey mortality than R. filiformis. The effects on shared prey suggest that the two predators are not substitutable in terms of the effect on the shared prey mortality. The mortality of A. bouvieri (IG prey) at low shared prey density was significantly different (p < 0.05) from high shared prey density. In view of predatory effect of the heteropteran predators on the dipteran larvae, the results suggest possible interference by the presence of A. bouvieri as an intermediate predator. It seems that the presence of heteropteran predators including A. bouvieri as IG prey may benefit the dipteran prey under situations when the density is low in tropical waters. The intensity of the predatory effect may differ based on the species composition at IG predator level. For mosquito biological control, the interactions between the predators may not be substitutable and are independent in their effects. PMID:26174962

  9. Distribution and Phylogenetic Analysis of Family 19 Chitinases in Actinobacteria

    PubMed Central

    Kawase, Tomokazu; Saito, Akihiro; Sato, Toshiya; Kanai, Ryo; Fujii, Takeshi; Nikaidou, Naoki; Miyashita, Kiyotaka; Watanabe, Takeshi

    2004-01-01

    In organisms other than higher plants, family 19 chitinase was first discovered in Streptomyces griseus HUT6037, and later, the general occurrence of this enzyme in Streptomyces species was demonstrated. In the present study, the distribution of family 19 chitinases in the class Actinobacteria and the phylogenetic relationship of Actinobacteria family 19 chitinases with family 19 chitinases of other organisms were investigated. Forty-nine strains were chosen to cover almost all the suborders of the class Actinobacteria, and chitinase production was examined. Of the 49 strains, 22 formed cleared zones on agar plates containing colloidal chitin and thus appeared to produce chitinases. These 22 chitinase-positive strains were subjected to Southern hybridization analysis by using a labeled DNA fragment corresponding to the catalytic domain of ChiC, and the presence of genes similar to chiC of S. griseus HUT6037 in at least 13 strains was suggested by the results. PCR amplification and sequencing of the DNA fragments corresponding to the major part of the catalytic domains of the family 19 chitinase genes confirmed the presence of family 19 chitinase genes in these 13 strains. The strains possessing family 19 chitinase genes belong to 6 of the 10 suborders in the order Actinomycetales, which account for the greatest part of the Actinobacteria. Phylogenetic analysis suggested that there is a close evolutionary relationship between family 19 chitinases found in Actinobacteria and plant class IV chitinases. The general occurrence of family 19 chitinase genes in Streptomycineae and the high sequence similarity among the genes found in Actinobacteria suggest that the family 19 chitinase gene was first acquired by an ancestor of the Streptomycineae and spread among the Actinobacteria through horizontal gene transfer. PMID:14766598

  10. Naturally Occurring Isoleucyl-tRNA Synthetase without tRNA-dependent Pre-transfer Editing*

    PubMed Central

    Cvetesic, Nevena; Dulic, Morana; Bilus, Mirna; Sostaric, Nikolina; Lenhard, Boris; Gruic-Sovulj, Ita

    2016-01-01

    Isoleucyl-tRNA synthetase (IleRS) is unusual among aminoacyl-tRNA synthetases in having a tRNA-dependent pre-transfer editing activity. Alongside the typical bacterial IleRS (such as Escherichia coli IleRS), some bacteria also have the enzymes (eukaryote-like) that cluster with eukaryotic IleRSs and exhibit low sensitivity to the antibiotic mupirocin. Our phylogenetic analysis suggests that the ileS1 and ileS2 genes of contemporary bacteria are the descendants of genes that might have arisen by an ancient duplication event before the separation of bacteria and archaea. We present the analysis of evolutionary constraints of the synthetic and editing reactions in eukaryotic/eukaryote-like IleRSs, which share a common origin but diverged through adaptation to different cell environments. The enzyme from the yeast cytosol exhibits tRNA-dependent pre-transfer editing analogous to E. coli IleRS. This argues for the presence of this proofreading in the common ancestor of both IleRS types and an ancient origin of the synthetic site-based quality control step. Yet surprisingly, the eukaryote-like enzyme from Streptomyces griseus IleRS lacks this capacity; at the same time, its synthetic site displays the 103-fold drop in sensitivity to antibiotic mupirocin relative to the yeast enzyme. The discovery that pre-transfer editing is optional in IleRSs lends support to the notion that the conserved post-transfer editing domain is the main checkpoint in these enzymes. We substantiated this by showing that under error-prone conditions S. griseus IleRS is able to rescue the growth of an E. coli lacking functional IleRS, providing the first evidence that tRNA-dependent pre-transfer editing in IleRS is not essential for cell viability. PMID:26921320

  11. Phylogenetic relationships among Lemuridae (Primates): evidence from mtDNA.

    PubMed

    Pastorini, Jennifer; Forstner, Michael R J; Martin, Robert D

    2002-10-01

    The family Lemuridae includes four genera: Eulemur, Hapalemur, Lemur,Varecia. Taxonomy and phylogenetic relationships between L. catta, Eulemur and Hapalemur, and of Varecia to these other lemurids, continue to be hotly debated. Nodal relationships among the five Eulemur species also remain contentious. A mitochondrial DNA sequence dataset from the ND 3, ND 4 L, ND 4 genes and five tRNAs (Gly, Arg, His, Ser, Leu) was generated to try to clarify phylogenetic relationships w ithin the Lemuridae. Samples (n=39) from all ten lemurid species were collected and analysed. Three Daubentonia madagascariensis were included as outgroup taxa. The approximately 2400 bp sequences were analysed using maximum parsimony, neighbor-joining and maximum likelihood methods. The results support monophyly of Eulemur, a basal divergence of Varecia, and a sister-group relationship for Lemur/Hapalemur. Based on tree topology, bootstrap values, and pairwise distance comparisons, we conclude thatVarecia and Eulemur both represent distinct genera separate from L. catta. H. griseus andH. aureus form a clade with strong support, but the sequence data do not permit robust resolution of the trichotomy involving H. simus, H. aureus/H. griseus and L. catta. Within Eulemur there is strong support for a clade containing E. fulvus, E. mongoz and E. rubriventer. However, analyses failed to clearly resolve relationships among those three species or with the more distantly related E. coronatus and E. macaco. Our sequencing data support the current subspecific status of E.m. macaco and E.m. flavifrons, and that of V.v. variegata and V.v. rubra. However, tree topology and relatively large genetic distances among individual V.v. variegata indicate that there may be more phylogenetic structure within this taxon than is indicated by current taxonomy. PMID:12393004

  12. Identification and functional analysis of genes controlling biosynthesis of 2-methylisoborneol

    PubMed Central

    Komatsu, Mamoru; Tsuda, Muneya; Ōmura, Satoshi; Oikawa, Hideaki; Ikeda, Haruo

    2008-01-01

    To identify the genes for biosynthesis of the off-flavor terpenoid alcohol, 2-methylisoborneol (2-MIB), the key genes encoding monoterpene cyclase were located in bacterial genome databases by using a combination of hidden Markov models, protein–family search, and the sequence alignment of their gene products. Predicted terpene cyclases were classified into three groups: sesquiterpene, diterpene, and other terpene cyclases. Genes of the terpene cyclase group that form an operon with a gene encoding S-adenosyl-l-methionine (SAM)-dependent methyltransferase were found in genome data of seven microorganisms belonging to actinomycetes, Streptomyces ambofaciens ISP5053, Streptomyces coelicolor A3(2), Streptomyces griseus IFO13350, Streptomyces lasaliensis NRRL3382R, Streptomyces scabies 87.22, Saccharopolyspora erythraea NRRL2338, and Micromonospora olivasterospora KY11048. Among six microorganisms tested, S. ambofaciens, S. coelicolor A3(2), S. griseus, and S. lasaliensis produced 2-MIB but M. olivasterospora produced 2-methylenebornane (2-MB) instead. The regions containing monoterpene cyclase and methyltransferase genes were amplified by PCR from S. ambofaciens, S. lasaliensis, and Saccharopolyspora erythraea, respectively, and their genes were heterologously expressed in Streptomyces avermitilis, which was naturally deficient of 2-MIB biosynthesis by insertion and deletion. All exoconjugants of S. avermitilis produced 2-MIB. Full-length recombinant proteins, monoterpene cyclase and methyltransferase of S. lasaliensis were expressed at high level in Escherichia coli. The recombinant methyltransferase catalyzed methylation at the C2 position of geranyl diphosphate (GPP) in the presence of SAM. 2-MIB was generated by incubation with GPP, SAM, recombinant methyltransferase, and terpene cyclase. We concluded that the biosynthetic pathway involves the methylation of GPP by GPP methyltransferase and its subsequent cyclization by monoterpene cyclase to 2-MIB. PMID

  13. Insights using a molecular approach into the life cycle of a tapeworm infecting great white sharks.

    PubMed

    Randhawa, Haseeb S

    2011-04-01

    The great white shark Carcharodon carcharias Linnaeus, 1758 is a versatile and fierce predator (and responsible for many shark attacks on humans). This apex predator feeds on a wide range of organisms including teleosts, other elasmobranchs, cephalopods, pinnipeds, and cetaceans. Although much is known about its diet, no trophic links have been empirically identified as being involved in the transmission of its tapeworm parasites. Recently, the use of molecular tools combined with phylogenetics has proven useful to identify larval and immature stages of marine tapeworms; utilization of the technique has been increasing rapidly. However, the usefulness of this approach remains limited by the availability of molecular data. Here, I employed gene sequence data from the D2 region of the large subunit of ribosomal DNA to link adults of the tapeworm Clistobothrium carcharodoni Dailey and Vogelbein, 1990 (Cestoda: Tetraphyllidea) to larvae for which sequence data for this gene are available. The sequences from the adult tapeworms were genetically identical (0% sequence divergence) to those available on GenBank for "SP" 'small' Scolex pleuronectis recovered from the striped dolphin (Stenella coeruleoalba) and Risso's dolphin (Grampus griseus). This study is the first to provide empirical evidence linking the trophic interaction between great white sharks and cetaceans as a definitive route for the successful transmission of a tetraphyllidean tapeworm. Using the intensity of infection data from this shark and from cetaceans as proxies for the extent of predation, I estimate that this individual shark would have consumed between 9 to 83 G. griseus , fresh, dead, or both, in its lifetime. PMID:21506792

  14. Phosphorylation of the AfsR product, a global regulatory protein for secondary-metabolite formation in Streptomyces coelicolor A3(2).

    PubMed Central

    Hong, S K; Kito, M; Beppu, T; Horinouchi, S

    1991-01-01

    The AfsR protein is essential for the biosynthesis at the wild-type level of A-factor, actinorhodin, and undecylprodigiosin in Streptomyces coelicolor A3(2) and Streptomyces lividans. Because overexpression of the afsR gene caused some deleterious effect on these strains, a multicopy plasmid carrying the whole afsR gene was introduced into Streptomyces griseus, from which a crude cell lysate was prepared as a protein source. The AfsR protein was purified to homogeneity from the cytoplasmic fraction through several steps of chromatography, including affinity column chromatography with ATP-agarose and use of anti-AfsR antibody for its detection. The molecular weight of AfsR was estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by gel filtration to be 105,300, which is in good agreement with that deduced from the nucleotide sequence of afsR. The purified AfsR protein was found to be phosphorylated through the transfer of the gamma-phosphate group of ATP in the presence of the cell extracts of S. coelicolor A3(2) and S. lividans. This phosphorylation proceeded very rapidly, and no competition was observed with CTP, GTP, UTP, or cyclic AMP. In the cell extract of S. griseus, no activity phosphorylating the AfsR protein was detected, suggesting that this activity is not generally present in Streptomyces spp. but is specific to certain species. It is conceivable that the extent of phosphorylation of the AfsR protein modulates its regulatory activity which, in turn, regulates expression of some target gene(s) involved in the secondary-metabolite formation in S. coelicolor A3(2). Images PMID:2007554

  15. Grados de comprobación de estudios de terapias integrales (PDQ®)—Versión para profesionales de salud

    Cancer.gov

    Información acerca de cómo sopesar la fuerza de los datos probatorios obtenidos de los estudios de investigación sobre terapias integrales, alternativas y complementarias en seres humanos con cáncer.

  16. In situ Management and Domestication of Plants in Mesoamerica

    PubMed Central

    Casas, Alejandro; Otero-Arnaiz, Adriana; Pérez-Negrón, Edgar; Valiente-Banuet, Alfonso

    2007-01-01

    Background and Aims Ethnobotanical studies in Mexico have documented that Mesoamerican peoples practise systems of in situ management of wild and weedy vegetation directed to control availability of useful plants. In situ management includes let standing, encouraging growing and protection of individual plants of useful species during clearance of vegetation, which in some cases may involve artificial selection. The aim of this study was to review, complement and re-analyse information from three case studies which examined patterns of morphological, physiological and genetic effects of artificial selection in plant populations under in situ management in the region. Methods Information on wild and in situ managed populations of the herbaceous weedy plants Anoda cristata and Crotalaria pumila, the tree Leucaena esculenta subsp. esculenta and the columnar cacti Escontria chiotilla, Polaskia chichipe and Stenocereus stellatus from Central Mexico was re-analysed. Analyses compared morphology and frequency of morphological variants, germination patterns, and population genetics parameters between wild and managed in situ populations of the species studied. Species of columnar cacti are under different management intensities and their populations, including cultivated stands of P. chichipe and S. stellatus, were also compared between species. Key Results Significant differences in morphology, germination patterns and genetic variation documented between wild, in situ managed and cultivated populations of the species studied are associated with higher frequencies of phenotypes favoured by humans in managed populations. Genetic diversity in managed populations of E. chiotilla and P. chichipe is slightly lower than in wild populations but in managed populations of S. stellatus variation was higher than in the wild. However, genetic distance between populations was generally small and influenced more by geographic distance than by management. Conclusions Artificial

  17. Stem biomechanics of three columnar cacti from the Sonoran Desert.

    PubMed

    Molina-Freaner, F; Tinoco-Ojanguren, C; Niklas, K

    1998-08-01

    The allometric relationship of stem length L with respect to mean stem diameter D was determined for 80 shoots of each of three columnar cactus species (Stenocereus thurberi, Lophocereus schottii, and S. gummosus) to determine whether this relationship accords with that predicted by each of three contending models purporting to describe the mechanical architecture of vertical shoots (i.e., geometric, stress, and elastic similitude, which predict L proportional to D(alpha), with alpha = 1/1, 1/2, and 2/3, respectively). In addition, anatomical, physical, and biomechanical stem properties were measured to determine how the stems of these three species maintain their elastic stability as they increase in size. Reduced major axis regression of L with respect to D showed that alpha = 2.82 ± 0.14 for S. thurberi, 2.32 ± 0.19 for L. schottii, and 4.21 ± 0.31 for S. gummosus. Thus, the scaling exponents for the allometry of L differed significantly from that predicted by each of the three biomechanical models. In contrast, these exponents were similar to that for the allometry previously reported for saguaro. Analyses of biomechanical data derived from bending tests performed on 30 stems selected from each of the three species indicated that the bulk stem tissue stiffness was roughly proportional to L2, while stem flexural rigidity (i.e., the ability to resist a bending force) scaled roughly as L3. Stem length was significantly and positively correlated with the volume fraction of wood, while regression analysis of the pooled data from the three species (i.e., 90 stems) indicated that bulk tissue stiffness scaled roughly as the 5/3-power of the volume fraction of wood in stems. These data were interpreted to indicate that wood served as the major stiffening agent in stems and that this tissue accumulates at a sufficient rate to afford unusually high scaling exponents tot stem length with respect to stem diameter (i.e., disproportionately large increments of stem length

  18. [Oleksandr Solomonovych Tsyperovych--gifted enzymologist, scientist and practician].

    PubMed

    Vynohradova, R P; Kolodzeĭs'ka, M V

    2007-01-01

    Professor O. S. Tsyperovich (15.12.1910-20.12.1976), Doctor of biology, was born in the city of Odessa, graduated from the Faculty of Chemistry of Shevchenko Kyiv State University as a specialist in organic chemistry (1930-1935). In 1935-1941 he worked at the Institute of Biochemistry of the Academy of Sciences of the Ukr.SSR (Kyiv) as a junior research worker, and then as a senior research worker at the Department of Enzymology. In 1941 O. S. Tsyperovich defended the thesis for the Candidate's degree dedicated to the investigation of synthetic effect of proteolytic enzymes, and he was awarded the title of the senior research worker. In 1941-1945 O. S. Tsyperovich struggled in the ranks of the Soviet Army, was awarded the Red Star Order, medals For Defense of Caucasus, For the Victory over Germany in the Great Patriotic War of 1941-1945. In 1946-1976 O. S. Tsyperovich worked at the Institute of Biochemistry of the Academy of Sciences of Ukraine. When investigating the mechanism of proteins denaturation he discovered the phenomenon of their "denaturational stabilization". New technological schemes of production of pepsin preparations were elaborated on the basis of the method of autholysis proposed by him. In 1954 O. S. Tsyperovich defended the thesis for the Doctor's Degree and was awarded the order The Badge of Honor. Beginning from 1963 he headed the laboratory, and from 1966 -- the Department of Chemistry and Biochemistry of Enzymes, in 1969 the title of professor was conferred on him. In the 60-70's O. S. Tsyperovich investigated hydrolytic enzymes of microorganisms with the purpose of their use in industry. Thus, the method of production of the preparation "pronasa" from Streptomyces griseus was developed, aminopeptidases, dipeptidases, a-amylase, cellulases, were investigated. Investigations in the field of preparative enzymology resulted in the development of technological scheme for creation of the following drugs for the purposes of medicine: medical

  19. Hospital Universiti Sains Malaysia (HUSM): 25 Years Of Excellent Service.

    PubMed

    Kamari, Zaidun

    2009-01-01

    Our Hospital University Sains Malaysia (HUSM) was given the Cabinet approval to exist under the Ministry of Education on 23 November 1982. The Deputy Prime Minister during that period, Yang Berhormat Tun Musa Hitam announced this after the cabinet meeting was held together with the presence of the Yang Berhormat Ministers of Health; and Education, Director of the Public Works Department and the Implementation and Coordinating Unit, Prime Minister's Department. The first patients moved in on 14 March 1983 and the inauguration of HUSM was done on 26 August 1984 by the Duli Yang Maha Mulia Tuanku Ismail Petra Ibni Al-Marhum Sultan Yahya Petra, the Sultan of Kelantan Darul Naim. HUSM celebrated it's 25th anniversary at the Dewan Utama, USM Health Campus on the 15th December 2008 which was inaugurated by Yang Berhormat, Minister of Higher Education Dato' Seri Mohamed Khaled Nordin. USM's Vice Chancellor Professor Tan Sri Dato' Dzulkifli Abdul Razak, Chairman of the USM Board of Directors Tan Sri Dato' Haji Dr. Ani bin Arope, Health Campus Director Professor Dato' Dr. Mafauzy Mohamed, former Campus Director, Dato' Prof Mohd Roslani Abdul Majid, the current and previous Hospital Directors and Deputy Directors since 1983 were present. The achievements of HUSM since its establishment and its vision to fulfil the University's Accelerated Programme for Excellence (APEX) are elaborated. PMID:22589644

  20. Differences in foraging activity of deep sea diving odontocetes in the Ligurian Sea as determined by passive acoustic recorders

    NASA Astrophysics Data System (ADS)

    Giorli, Giacomo; Au, Whitlow W. L.; Neuheimer, Anna

    2016-01-01

    Characterizing the trophic roles of deep-diving odontocete species and how they vary in space and time is challenged by our ability to observe foraging behavior. Though sampling methods are limited, foraging activity of deep-diving odontocetes can be monitored by recording their biosonar emissions. Daily occurrence of echolocation clicks was monitored acoustically for five months (July-December 2011) in the Ligurian Sea (Mediterranean Sea) using five passive acoustic recorders. Detected odontocetes included Cuvier's beaked whales (Zipuhius cavirostris), sperm whales (Physeter macrocephalus), Risso's dolphins (Grampus griseus), and long-finned pilot whales (Globicephala melas). The results indicated that the foraging strategies varied significantly over time, with sperm whales switching to nocturnal foraging in late September whereas Risso's dolphins and pilot whales foraged mainly at night throughout the sampling period. In the study area, winter nights are about five hours longer than summer nights and an analysis showed that pilot whales and Risso's dolphins adjusted their foraging activity with the length of the night, foraging longer during the longer winter nights. This is the first study to show that marine mammals exhibit diurnal foraging patterns closely correlated to sunrise and sunset.

  1. Data from camera surveys identifying co-occurrence and occupancy linkages between fishers (Pekania pennanti), rodent prey, mesocarnivores, and larger predators in mixed-conifer forests.

    PubMed

    Sweitzer, Rick A; Furnas, Brett J

    2016-03-01

    These data provide additional information relevant to the frequency of fisher detections by camera traps, and single-season occupancy and local persistence of fishers in small patches of forest habitats detailed elsewhere, "Landscape Fuel Reduction, Forest Fire, and Biophysical Linkages to Local Habitat Use and Local Persistence of Fishers (Pekania pennanti) in Sierra Nevada Mixed-conifer Forests" [10]. The data provides insight on camera trap detections of 3 fisher predators (bobcat [Lynx rufus]). Coyote [Canis latrans], mountain lion [Puma concolor], 5 mesocarnivores in the same foraging guild as fishers (gray fox [Urocyon cinereoargenteus]) ringtail [Bassariscus astutus], marten [Martes americana], striped skunk [Mephitis mephitis] spotted skunk [Spilogale gracilis], and 5 Sciuridae rodents that fishers consume as prey (Douglas squirrel [Tamiasciurus douglasii]), gray squirrel [Sciurus griseus], northern flying squirrel [Glaucomys sabrinus], long-eared chipmunk [Neotamias quadrimaculatus], California ground squirrel [Spermophilus beecheyi]. We used these data to identify basic patterns of co-occurrence with fishers, and to evaluate the relative importance of presence of competing mesocarnivores, rodent prey, and predators for fisher occupancy of small, 1 km(2) grid cells of forest habitat. PMID:26937448

  2. First report of gastrocotylinean post-oncomiracidia (Platyhelminthes: Monogenoidea: Heteronchoinea) on gills of flyingfish (Exocoetidae), snapper (Lutjanidae), dolphinfish (Coryphaenidae), and amberjack (Carangidae) from the Gulf of Mexico: decoy hosts and the dilution effect.

    PubMed

    Kritsky, Delane C; Bullard, Stephen A; Bakenhaster, Micah D

    2011-09-01

    Larvae, identified as post-oncomiracidia of the suborder Gastrocotylinea (Monogenoidea), were collected from formalin-fixed gills excised from six species of marine fishes captured from the Gulf of Mexico off Mississippi and Florida: common dolphinfish, Coryphaena hippurus and pompano dolphinfish, Coryphaena equiselis (both Perciformes, Coryphaenidae); gray snapper, Lutjanus griseus (Perciformes, Lutjanidae); greater amberjack, Seriola dumerili (Perciformes, Carangidae); and Atlantic flyingfish, Cheilopogon melanurus and sailfin flyingfish, Parexocoetus hillianus (both Beloniformes and Exocoetidae). Based on a combination of diagnostic morphological features, the specimens were divided into two basic forms, each of which was further subdivided into two morphotypes. No gastrocotylinean post-oncomiracidium had been reported previously from these hosts. Of the six host species, only C. hippurus serves as a host (unconfirmed) for the adult of a gastrocotylinean species, suggesting that the recorded fishes from the Gulf of Mexico comprise dead-end hosts acting as decoys for the oncomiracidia. These comparatively non-susceptible "decoy hosts" apparently dilute the susceptible fish-host population and by intercepting infective larvae (oncomiracidia) decrease the abundance of parasites on their typical hosts. PMID:21497672

  3. Philometrid nematodes infecting fishes from the Everglades National Park, Florida, U.S.A.

    PubMed

    Moravec, Frantisek; Bakenhaster, Micah

    2010-09-01

    The following three species of the Philometridae (Nematoda: Dracunculoidea) are described from marine perciform fishes of the Everglades National Park (northern Gulf of Mexico), Florida, U.S.A.: Philometra brevispicula sp. n. (male and females) from the subcutaneous tissue of mouth of the gray snapper Lutjanus griseus (Linnaeus) (Lutjanidae), Philometroides grandipapillatus sp. n. (only females) from pectoral fin muscle of the crevalle jack Caranx hippos (Linnaeus) (Carangidae), and Caranginema americanum Moravec, Montoya-Mendoza et Salgado-Maldonado, 2008 (females) from the subcutaneous fascia of trunk muscle in crevalle jack C. hippos. Philometra brevispicula is mainly characterized by small cephalic papillae of the external circle, the absence of oesophageal teeth and the presence of small caudal projections in gravid female, markedly short spicules (45 microm) in male, and by its location in the host. Philometroides grandipapillatus differs from congeners mainly in the shape of the cephalic region (narrow, conspicuously protruding), large cephalic papillae of the external circle and the absence of caudal projections in female, and by the site of infection in the host. Caranginema americanum is for the first time recorded from the northern Gulf of Mexico. PMID:20941913

  4. Sylvatic maintenance of Borrelia burgdorferi (Spirochaetales) in Northern California: untangling the web of transmission.

    PubMed

    Brown, R N; Peot, M A; Lane, R S

    2006-07-01

    Lyme borreliosis is associated with several genospecies of Borrelia burgdorferi sensu lato (s.l.) (Spirochaetales), but human disease has been associated only with Borrelia burgdorferi sensu stricto (s.s.) Johnson, Schmid, Hyde, Steigerwalt & Brenner in the western United States. Restriction fragment length polymorphism (RFLP) analysis of rrf-rrl amplicons from 124 tick and mammalian isolates from various habitats yielded 13 RFLP patterns. Of these patterns, six were patterns previously associated either with Borrelia bissettii Postic, Marti Ras, Lane, Hendson & Baranton or Borrelia burgdorferi s.s., and the remaining seven patterns belonged to diverse and previously uncharacterized Borrelia spp. Uncharacterized Borrelia spp. were cultured most frequently from Ixodes spinipalpis Hadwen & Nuttall and California kangaroo rats, Dipodomys californicus Merriam, inhabiting grasslands, and B. bissettii from I. spinipalpis and dusky-footed woodrats, Neotoma fuscipes Baird, associated with oak woodlands or chaparral. B. burgdorferi s.s. typically was isolated from host-seeking Ixodes pacificus Cooley & Kohls collected in dense oak woodlands, woodland-grass, or redwood forests. Although some isolates of B. burgdorferi s.s. were cultured from woodrats, there was no clear association of this human pathogen with any vertebrate host. These findings, along with recent evidence indicating that the western gray squirrel, Sciurus griseus Ord, may be an important reservoir of B. burgdorferi s.s. in Californian oak woodlands, suggest that our earlier hypothesis implicating an enzootic cycle involving woodrats and I. spinipalpis is insufficient to account for observed patterns of infection in nature. PMID:16892634

  5. Introduced and native congeners use different resource allocation strategies to maintain performance during infection.

    PubMed

    Coon, Courtney A C; Brace, Amber J; McWilliams, Scott R; McCue, Marshall D; Martin, Lynn B

    2014-01-01

    Abstract Hosts can manage parasitic infections using an array of tactics, which are likely to vary contingent on coevolutionary history between the host and the parasite. Here we asked whether coping ability of congeners that differ in host-parasite coevolutionary history differed in response to experimental infections with a coccidian parasite. House sparrows (Passer domesticus) and gray-headed sparrows (Passer griseus) are sympatric and ecologically similar, but house sparrows are recent colonizers of Kenya, the site of our comparison, whereas gray-headed sparrows are native. We evaluated three variables as barometers of infection coping ability: vertical flight, pectoral muscle size, and fat score. We also measured routing of a dose of (13)C-labeled leucine, an essential amino acid, among tissues to compare resource allocation strategies in response to infection. We found that burden effects on performance were minimal in both species, but house sparrows maintained considerably higher burdens than gray-headed sparrows regardless of exposure. House sparrows also had more exogeneous leucine tracer in all tissues after 24 h, demonstrating a difference in the way the two species allocate or distribute resources. We argue that house sparrows may be maintaining larger resource reserves to mitigate costs associated with exposure and infection. Additionally, in response to increased parasite exposure, gray-headed sparrows had less leucine tracer in their spleens and more in their gonads, whereas house sparrows did not change allocation, perhaps indicating a trade-off that is not experienced by the introduced species. PMID:24940920

  6. A new species of Limatulichthys Isbrücker & Nijssen (Loricariidae, Loricariinae) from the western Guiana Shield .

    PubMed

    Londoño-Burbano, Alejandro; Lefebvre, Stéphanie L; Lujan, Nathan K

    2014-01-01

    Limatulichthys nasarcus n. sp. is described as a new species based on 15 specimens from the Ventuari and Caura Rivers in Southern Venezuela. The new species can be distinguished from its only congener, L. griseus, by the presence of anterior abdominal plates half the size of those at center of abdomen (vs. plates similar in size); distinct spots less than half of diameter of naris across entire dorsum, including snout and head (vs. indistinct dorsal spots larger or equal than diameter of naris); lateral portions of head and opercle with dark well-defined spots larger than those on dorsum (vs. spots on lateral portions of head and opercle equal in size to those on remainder of body); snout profile in dorsal view broadly rounded (vs. acutely triangular); head longer (21.4-24.2 SL vs. 17.7-21.0%); and anal fin longer (15.7-18.0 SL vs. 13.7-15.6%). Distinctiveness of the two species is further supported by their non-overlapping distribution in multivariate morphospace. The disjunct distribution of L. nasarcus across both the Caura and Ventuari rivers exclusive of the main Orinoco River channel contributes to a growing body of evidence supporting the historical connection between headwaters of these drainages. The hypothesized existence of a 'proto-Berbice' paleodrainage provides one explanation for such a connection. PMID:25543793

  7. Shearwater Foraging in the Southern Ocean: The Roles of Prey Availability and Winds

    PubMed Central

    Raymond, Ben; Shaffer, Scott A.; Sokolov, Serguei; Woehler, Eric J.; Costa, Daniel P.; Einoder, Luke; Hindell, Mark; Hosie, Graham; Pinkerton, Matt; Sagar, Paul M.; Scott, Darren; Smith, Adam; Thompson, David R.; Vertigan, Caitlin; Weimerskirch, Henri

    2010-01-01

    Background Sooty (Puffinus griseus) and short-tailed (P. tenuirostris) shearwaters are abundant seabirds that range widely across global oceans. Understanding the foraging ecology of these species in the Southern Ocean is important for monitoring and ecosystem conservation and management. Methodology/Principal Findings Tracking data from sooty and short-tailed shearwaters from three regions of New Zealand and Australia were combined with at-sea observations of shearwaters in the Southern Ocean, physical oceanography, near-surface copepod distributions, pelagic trawl data, and synoptic near-surface winds. Shearwaters from all three regions foraged in the Polar Front zone, and showed particular overlap in the region around 140°E. Short-tailed shearwaters from South Australia also foraged in Antarctic waters south of the Polar Front. The spatial distribution of shearwater foraging effort in the Polar Front zone was matched by patterns in large-scale upwelling, primary production, and abundances of copepods and myctophid fish. Oceanic winds were found to be broad determinants of foraging distribution, and of the flight paths taken by the birds on long foraging trips to Antarctic waters. Conclusions/Significance The shearwaters displayed foraging site fidelity and overlap of foraging habitat between species and populations that may enhance their utility as indicators of Southern Ocean ecosystems. The results highlight the importance of upwellings due to interactions of the Antarctic Circumpolar Current with large-scale bottom topography, and the corresponding localised increases in the productivity of the Polar Front ecosystem. PMID:20532034

  8. Statistical power to detect change in a mangrove shoreline fish community adjacent to a nuclear power plant.

    PubMed

    Dolan, T E; Lynch, P D; Karazsia, J L; Serafy, J E

    2016-03-01

    An expansion is underway of a nuclear power plant on the shoreline of Biscayne Bay, Florida, USA. While the precise effects of its construction and operation are unknown, impacts on surrounding marine habitats and biota are considered by experts to be likely. The objective of the present study was to determine the adequacy of an ongoing monitoring survey of fish communities associated with mangrove habitats directly adjacent to the power plant to detect fish community changes, should they occur, at three spatial scales. Using seasonally resolved data recorded during 532 fish surveys over an 8-year period, power analyses were performed for four mangrove fish metrics (fish diversity, fish density, and the occurrence of two ecologically important fish species: gray snapper (Lutjanus griseus) and goldspotted killifish (Floridichthys carpio). Results indicated that the monitoring program at current sampling intensity allows for detection of <33% changes in fish density and diversity metrics in both the wet and the dry season in the two larger study areas. Sampling effort was found to be insufficient in either season to detect changes at this level (<33%) in species-specific occurrence metrics for the two fish species examined. The option of supplementing ongoing, biological monitoring programs for improved, focused change detection deserves consideration from both ecological and cost-benefit perspectives. PMID:26903208

  9. Development of a method to quantify gene expression levels for glycosylation pathway genes in chinese hamster ovary cell cultures.

    PubMed

    Clark, Kevin J-R; Harcum, Sarah W; Griffiths, Jennifer; Bailey, Kevin M

    2005-06-01

    Changes in protein glycosylation owing to changes in environmental conditions are not well understood. To better understand these relationships, methods to quantify controlling factors are needed. Because enzymes are translated from genes, the ability to quantify gene expression levels for glycosylation-related enzymes would be advantageous. We developed quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) assays to monitor gene expression in Chinese hamster ovary (CHO) cells for five terminal glycosylation genes. The five enzymes were sialidase, a putative alpha2,3-sialyltransferase, beta1,4-galactosyltransferase, cytosine monophosphate-sialic acid transporter, and uracil diphosphate-galactosyl transporter. Four of these CHO cell genes were publicly available from GenBank; however, the alpha2,3-sialyltransferase gene for Cricetulus griseus (CHO cell species) was not available and, therefore, was sequenced as a part of this work. The qRT-PCR primers and probes (based on the TaqMan chemistry) were designed and validated for these five genes. The gene expression profiles were obtained for CHO cells producing the recombinant interleukin-4/13 cytokine trap molecule in batch reactors. PMID:15917580

  10. Utilization of soluble starch by a recombinant Corynebacterium glutamicum strain: growth and lysine production.

    PubMed

    Seibold, Gerd; Auchter, Marc; Berens, Stephan; Kalinowski, Jörn; Eikmanns, Bernhard J

    2006-07-13

    Corynebacterium glutamicum, well known for the industrial production of amino acids, grows aerobically on a variety of mono- and disaccharides and on alcohols and organic acids as single or combined sources of carbon and energy. Members of the genera Corynebacterium and Brevibacterium were here tested for their ability to use the homopolysaccharide starch as a substrate for growth. None of the 24 type strains tested showed growth on or degradation of this substrate, indicating that none of the strains synthesized and secreted starch-degrading enzymes. Introducing the Streptomyces griseus amy gene on an expression vector into the lysine-producer C. glutamicum DM1730, we constructed a C. glutamicum strain synthesizing and secreting alpha-amylase into the culture broth. Although some high-molecular-weight degradation products remained in the culture broth, this recombinant strain effectively used soluble starch as carbon and energy substrate for growth and also for lysine production. Thus, employment of our construct allows avoidance of the cost-intensive enzymatic hydrolysis of the starch, which commercially is used as a substrate in industrial amino acid fermentations. PMID:16488498

  11. Elk3 from hamster--a ternary complex factor with strong transcriptional repressor activity.

    PubMed

    Hjortoe, Gertrud Malene; Weilguny, Dietmar; Willumsen, Berthe Marie

    2005-01-01

    Elk3 belongs to the Ets family of transcription factors, which are regulated by the Ras/mitogen-activated protein kinase-signaling pathway. In the absence of Ras, this protein is a strong inhibitor of transcription and may be directly involved in regulation of growth by downregulating the transcription of genes that are activated during entry into G1. We have isolated the Cricetulus griseus Elk3 gene from the Chinese hamster ovary (CHO) cell line and investigated the transcriptional potential of this factor. Transient transfections revealed that, in addition to its regulation of the c-fos promoter, Elk3 from CHO cells seems to inhibit other promoters controlling expression of proteins involved in G1/S phase progression; Cyclin D1 and DHFR. As has been described for the Elk3 homologs Net (Mouse) and Sap-2 (Human), the results of the present study further indicate that hamster Elk3 is a target of the Ras-Raf-MAPK pathway, and cotransfections with constitutively active H-ras relieves its negative transcriptional activity. No cells stably expressing exogenous Elk3 could be obtained, possibly due to an unspecified toxic or growth retarding effect. These findings support a possible role for Elk3 in growth regulation and reveal a high degree of homology for this protein across species. PMID:15684718

  12. Investigation of neutral endopeptidases (EC 3.4.24.11) and of neutral proteinases (EC 3.4.24.4) using a new sensitive two-stage enzymatic reaction.

    PubMed

    Indig, F E; Ben-Meir, D; Spungin, A; Blumberg, S

    1989-09-25

    A sensitive two-stage enzymatic reaction for mammalian and bacterial metalloendopeptidases has been developed using the substrate 3-carboxypropanoyl-alanyl-alanyl-leucine-4-nitroanilide supplemented with Streptomyces griseus amino-peptidase. Neutral endopeptidase EC 3.4.24.11 from bovine kidney hydrolyzes the substrate (pH 7.5, 25 degrees C) with a catalytic efficiency (kcat = 1.2 x 10(2) s-1, Km = 0.15 mM) of the highest ever reported for the enzyme acting on synthetic chromophoric and fluorogenic substrates. Thermolysin hydrolyzes the substrate at a faster rate (kcat = 1.2 x 10(3) s-1) but the overall efficiency is diminished by a higher Km (4.2 mM). Suspensions of human neutrophil cells and culture filtrates of Bacillus cereus have been assayed sensitively for their neutral endopeptidases and neutral proteinase activities, respectively. The assay provides a convenient tool for the kinetic investigation of neutral endopeptidases and neutral proteinases and for assessing their function in biological systems. PMID:2507355

  13. Isolation and evaluation of proteolytic actinomycete isolates as novel inducers of pearl millet downy mildew disease protection.

    PubMed

    Jogaiah, Sudisha; Kurjogi, Mahantesh; Govind, Sharathchandra Ramasandra; Huntrike, Shekar Shetty; Basappa, Vedamurthy Ankala; Tran, Lam-Son Phan

    2016-01-01

    Native endophytic actinomycetes isolated from pearl millet roots were examined for their efficacy to protect pearl millet against downy mildew. Nineteen of 39 isolates were found to be proteolytic, of which 7 strains could directly suppress the sporangium formation of Sclerospora graminicola, the pearl millet downy mildew pathogen. Thus, mycelial suspensions containing either spores or cell-free extract of these 7 isolates were used for seed-coating and -soaking treatments to test for their induction of downy mildew resistance. Results indicated that seed-coating overall provided better protection to downy mildew than seed-soaking. In both treatments, the tested isolates demonstrated differential abilities in downy mildew disease protection, with Streptomyces griseus SJ_UOM-07-09 and Streptosporangium roseum SJ_UOM-18-09 showing the highest protection rates. Additionally, the levels of disease protection conferred by the actinomycetes were just slightly lower than that of the systemic fungicide Apron, suggesting their effectiveness. Further studies revealed that the more rapid root colonization by SJ_UOM-18-09 resulted in faster and higher induced resistance in comparison with SJ_UOM-07-09 under greenhouse conditions, indicating that SJ_UOM-18-09 was superior than SJ_UOM-07-09 in inducing resistance. Results from this study provide comprehensive information on biocontrol functions of SJ_UOM- 18-09 with great potential to control downy mildew disease in pearl millet. PMID:27499196

  14. Static inflation and deflation pressure–volume curves from excised lungs of marine mammals

    PubMed Central

    Fahlman, Andreas; Loring, Stephen H.; Ferrigno, Massimo; Moore, Colby; Early, Greg; Niemeyer, Misty; Lentell, Betty; Wenzel, Frederic; Joy, Ruth; Moore, Michael J.

    2011-01-01

    SUMMARY Excised lungs from eight marine mammal species [harp seal (Pagophilus groenlandicus), harbor seal (Phoca vitulina), gray seal (Halichoerus grypush), Atlantic white-sided dolphin (Lagenorhynchus acutus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), long-finned pilot whale (Globicephala melas) and harbor porpoise (Phocoena phocoena)] were used to determine the minimum air volume of the relaxed lung (MAV, N=15), the elastic properties (pressure–volume curves, N=24) of the respiratory system and the total lung capacity (TLC). Our data indicate that mass-specific TLC (sTLC, l kg–1) does not differ between species or groups (odontocete vs phocid) and agree with that estimated (TLCest) from body mass (Mb) by applying the equation: TLCest=0.135 Mb0.92. Measured MAV was on average 7% of TLC, with a range from 0 to 16%. The pressure–volume curves were similar among species on inflation but diverged during deflation in phocids in comparison with odontocetes. These differences provide a structural basis for observed species differences in the depth at which lungs collapse and gas exchange ceases. PMID:22031747

  15. Data from camera surveys identifying co-occurrence and occupancy linkages between fishers (Pekania pennanti), rodent prey, mesocarnivores, and larger predators in mixed-conifer forests

    PubMed Central

    Sweitzer, Rick A.; Furnas, Brett J.

    2016-01-01

    These data provide additional information relevant to the frequency of fisher detections by camera traps, and single-season occupancy and local persistence of fishers in small patches of forest habitats detailed elsewhere, “Landscape Fuel Reduction, Forest Fire, and Biophysical Linkages to Local Habitat Use and Local Persistence of Fishers (Pekania pennanti) in Sierra Nevada Mixed-conifer Forests” [10]. The data provides insight on camera trap detections of 3 fisher predators (bobcat [Lynx rufus]). Coyote [Canis latrans], mountain lion [Puma concolor], 5 mesocarnivores in the same foraging guild as fishers (gray fox [Urocyon cinereoargenteus]) ringtail [Bassariscus astutus], marten [Martes americana], striped skunk [Mephitis mephitis] spotted skunk [Spilogale gracilis], and 5 Sciuridae rodents that fishers consume as prey (Douglas squirrel [Tamiasciurus douglasii]), gray squirrel [Sciurus griseus], northern flying squirrel [Glaucomys sabrinus], long-eared chipmunk [Neotamias quadrimaculatus], California ground squirrel [Spermophilus beecheyi]. We used these data to identify basic patterns of co-occurrence with fishers, and to evaluate the relative importance of presence of competing mesocarnivores, rodent prey, and predators for fisher occupancy of small, 1 km2 grid cells of forest habitat. PMID:26937448

  16. Impact of forest type and management strategy on avian densities in the Mississippi Alluvial Valley, USA

    USGS Publications Warehouse

    Twedt, D.J.; Wilson, R.R.; Henne-Kerr, J.L.; Hamilton, R.B.

    1999-01-01

    Avian territory densities were determined from 20 Breeding Bird Censuses in mature (>30 years) bottomland hardwood stand: and 18 Breeding Bird Censuses in young (6-9 years old) cottonwood (Populas deltoides) plantations in the Mississippi Alluvial Valley. Avian species richness, diversity, and territory density were greater (p 0.05). Even so, detrended correspondence analysis based on avian territory densities readily segregated forest types and silvicultural treatments. Timber harvest within bottomland hardwood stands resulted in a shift in bird communities toward those found in cottonwood stands by increasing the densities of early-successional species such as Indigo Bunting (Passerina cyanea), Yellow-breasted Chat (Icteria virens), and Common Yellowthroat (Geothlypis trichas). Conversely, regenerating cottonwood stands from root sprouts, rather than planting stem cuttings, resulted in a shift in bird communities toward those found in bottomland hardwood stands by increasing densities of species such as White-eyed Vireo (Vireo griseus) and Wood Thrush (Hylocichla mustelina). Tree species diversity, angular canopy cover, and midstory density were positively associated with bird species assemblages in bottomland hardwood stands, whereas vegetation density at ground level was positively associated with bird communities in cottonwood plantations. Conversion of agricultural fields to short-rotation cottonwood plantations results in increased breeding bird populations by adding up to 140 additional territories 40 ha-1. Even so, relative conservation values, derive, from indicator species analysis and Partners in Flight concern scores, suggest that mature bottomland hardwood forests are twice as 'valuable' for bird conservation as are cottonwood plantations.

  17. Biosystematics of alkaliphilic streptomycetes isolated from seven locations across a beach and dune sand system.

    PubMed

    Antony-Babu, Sanjay; Goodfellow, Michael

    2008-11-01

    Alkaliphilic streptomycetes were isolated from composite sand samples collected from six out of seven locations across a beach and dune sand system using starch-casein-nitrate agar supplemented with cycloheximide and buffered to pH 10.5. The isolates had colonial and chemotaxonomic properties consistent with their classification in the genus Streptomyces. They were assigned to 49 multimembered and 114 single-membered colour-groups given their ability to produce pigments on oatmeal and peptone-yeast-extract-iron agars and to corresponding taxa based on whole-genome rep-PCR banding patterns. Twenty-four isolates representing the colour and rep-PCR groups grew well from pH 5 to 11, and optimally at pH 9, as did phylogenetically close members of the Streptomyces griseus 16S rRNA gene clade. One hundred and twelve representative alkaliphilic streptomycetes formed a heterogeneous but distinct clade in the Streptomyces 16S rRNA gene tree. A 3-dimensional representation of 16S rRNA sequence data showed that the alkaliphilic streptomycetes formed a distinct group in multidimensional taxospace. It is evident that alkaliphilic streptomycetes are common in the beach and dune sand system and that representatives of this community form new centers of taxonomic variation within the genus Streptomyces that can be equated with species. PMID:18777141

  18. Variation in acoustic behavior of delphinids in the Pacific Ocean based on school size and species composition

    NASA Astrophysics Data System (ADS)

    Rankin, Shannon; Barlow, Jay

    2005-04-01

    Variation in acoustic behavior based on school size and species composition was examined for surveys in the eastern tropical Pacific (2000), along the U.S. West Coast (2001), and in the U.S. EEZ surrounding Hawaii (2002). Sounds were monitored using a towed hydrophone array, and vocal schools were defined as those producing any combination of whistles, burst pulses, and/or echolocation clicks. Delphinid schools containing mixed species were consistently more vocal than single species schools. Vocal schools of Stenella attenuata, S. longirostris, Delphinus delphis, and Lissodelphis borealis were significantly larger than non-vocal schools. Vocal schools of Tursiops truncatus and Grampus griseus were somewhat larger than non-vocal schools, although this relationship was not significant. There was no relationship between group size and vocal activity for S. coeruleoalba, Steno bredanensis, and Globicephala spp. For species without a strong group size effect, all but T. truncatus were more vocal in the Hawaiian waters. The ability to use acoustic techniques in dolphin population estimation depends on their effectiveness in consistently detecting dolphin schools. This study suggests that small single-species schools of S. attenuata, S. longirostris, D. delphis, and L. borealis are more likely to be missed during acoustic monitoring in these regions.

  19. Historical and current records of aquarium cetaceans in China.

    PubMed

    Zhang, Peijun; Sun, Ni; Yao, Zhiping; Zhang, Xianfeng

    2012-01-01

    The number of cetaceans housed in aquariums in China is increasing. Detailed information on the historical and current population status has not been reported, despite its importance for successful breeding and population management. Questionnaires were conducted between December 2006 and May 2009, and the information was used to construct studbooks. Our survey showed that 10 species had been introduced to aquariums since 1978, including 26 (with 15 in the current population) finless porpoises (Neophocaena phocaenoides), 5 (5) false killer whales (Pseudorca crassidens), 94 (80) common bottlenose dolphins (Tursiops truncatus), 48 (30) Indo-Pacific bottlenose dolphins (Tursiops aduncus), 36 (32) beluga whales (Delphinapterus leucas), 10 (10) pantropical spotted dolphins (Stenella attenuata), 8 (8) Risso's dolphins (Grampus griseus), 2 (2) short-finned pilot whales (Globicephala macrorhynchus), 2 (2) Pacific white-sided dolphins (Lagenorhynchus obliquidens), and 5 (0) baiji dolphins (Lipotes vexillifer). The number of cetaceans has increased markedly in the past 32 years, especially since 1995. Currently, 184 individuals are under human care throughout China, a number larger than any other country with an International Species Information System membership. In addition, the Annual Survival Rates of bottlenose dolphins (0.959) and beluga whales (0.968) were found higher than those reported previously (0.93-0.951 and 0.94-0.954, respectively). PMID:21674602

  20. Population identification of western hemisphere shorebirds throughout the annual cycle

    USGS Publications Warehouse

    Haig, Susan M.; Gratto-Trevor, C. L.; Mullins, Thomas D.; Colwell, M.A.

    1997-01-01

    Identification of relationships among geographically distinct populations of migratory species can provide an understanding of breeding and natal philopatry, migration pathways, and population mixing during winter. We used random amplified polymorphic DNA (RAPD) analyses to search for markers specific to difficult-to-differentiate shorebird species (e.g. long-billed dowitcher Limnodromus scolopaceus and short-billed dowitcher L. griseus) as well as geographically distinct breeding populations of Hudsonian godwits Limosa haemastica, red-necked phalaropes Phalaropus lobatus, semipalmated plovers Charadrius semipalmatus, dunlin Calidris alpina, pectoral sandpipers C. melanotos, semipalmated sandpipers C. pusilla and western sandpipers C. mauri. Markers clearly differentiated all shorebird species. Estimates of population differentiation varied greatly among species (FST= 0.095a??0.685) and correlated with interspecific variation in philopatry and geographical separation of breeding populations. We assigned individuals to putative breeding locales with greater certainty in well-differentiated species than in poorly differentiated species. Our findings indicate specific phylogeographical structure varies among species, which has strong implications for conservation of habitats within migratory corridors. We suggest that RAPDs are useful in identifying geographical populations of migratory species and that molecular markers should be considered for tracking migratory birds throughout the annual cycle.

  1. Automatic classification of delphinids based on the representative frequencies of whistles.

    PubMed

    Lin, Tzu-Hao; Chou, Lien-Siang

    2015-08-01

    Classification of odontocete species remains a challenging task for passive acoustic monitoring. Classifiers that have been developed use spectral features extracted from echolocation clicks and whistle contours. Most of these contour-based classifiers require complete contours to reduce measurement errors. Therefore, overlapping contours and partially detected contours in an automatic detection algorithm may increase the bias for contour-based classifiers. In this study, classification was conducted on each recording section without extracting individual contours. The local-max detector was used to extract representative frequencies of delphinid whistles and each section was divided into multiple non-overlapping fragments. Three acoustical parameters were measured from the distribution of representative frequencies in each fragment. By using the statistical features of the acoustical parameters and the percentage of overlapping whistles, correct classification rate of 70.3% was reached for the recordings of seven species (Tursiops truncatus, Delphinus delphis, Delphinus capensis, Peponocephala electra, Grampus griseus, Stenella longirostris longirostris, and Stenella attenuata) archived in MobySound.org. In addition, correct classification rate was not dramatically reduced in various simulated noise conditions. This algorithm can be employed in acoustic observatories to classify different delphinid species and facilitate future studies on the community ecology of odontocetes. PMID:26328716

  2. Retransformation of marker-free potato for enhanced resistance against fungal pathogens by pyramiding chitinase and wasabi defensin genes.

    PubMed

    Khan, Raham Sher; Darwish, Nader Ahmed; Khattak, Bushra; Ntui, Valentine Otang; Kong, Kynet; Shimomae, Kazuki; Nakamura, Ikuo; Mii, Masahiro

    2014-09-01

    Multi-auto-transformation vector system has been one of the strategies to produce marker-free transgenic plants without using selective chemicals and plant growth regulators and thus facilitating transgene stacking. In the study reported here, retransformation was carried out in marker-free transgenic potato CV. May Queen containing ChiC gene (isolated from Streptomyces griseus strain HUT 6037) with wasabi defensin (WD) gene (isolated from Wasabia japonica) to pyramid the two disease resistant genes. Molecular analyses of the developed shoots confirmed the existence of both the genes of interest (ChiC and WD) in transgenic plants. Co-expression of the genes was confirmed by RT-PCR, northern blot, and western blot analyses. Disease resistance assay of in vitro plants showed that the transgenic lines co-expressing both the ChiC and WD genes had higher resistance against the fungal pathogens, Fusarium oxysporum (Fusarium wilt) and Alternaria solani (early blight) compared to the non-transformed control and the transgenic lines expressing either of the ChiC or WD genes. The disease resistance potential of the transgenic plants could be increased by transgene stacking or multiple transformations. PMID:24802621

  3. 3-Amino-4-hydroxybenzoic acid production from sweet sorghum juice by recombinant Corynebacterium glutamicum.

    PubMed

    Kawaguchi, Hideo; Sasaki, Kengo; Uematsu, Kouji; Tsuge, Yota; Teramura, Hiroshi; Okai, Naoko; Nakamura-Tsuruta, Sachiko; Katsuyama, Yohei; Sugai, Yoshinori; Ohnishi, Yasuo; Hirano, Ko; Sazuka, Takashi; Ogino, Chiaki; Kondo, Akihiko

    2015-12-01

    The production of the bioplastic precursor 3-amino-4-hydroxybenzoic acid (3,4-AHBA) from sweet sorghum juice, which contains amino acids and the fermentable sugars sucrose, glucose and fructose, was assessed to address the limitations of producing bio-based chemicals from renewable feedstocks. Recombinant Corynebacterium glutamicum strain KT01 expressing griH and griI derived from Streptomyces griseus produced 3,4-AHBA from the sweet sorghum juice of cultivar SIL-05 at a final concentration (1.0 g l(-1)) that was 5-fold higher than that from pure sucrose. Fractionation of sweet sorghum juice by nanofiltration (NF) membrane separation (molecular weight cut-off 150) revealed that the NF-concentrated fraction, which contained the highest concentrations of amino acids, increased 3,4-AHBA production, whereas the NF-filtrated fraction inhibited 3,4-AHBA biosynthesis. Amino acid supplementation experiments revealed that leucine specifically enhanced 3,4-AHBA production by strain KT01. Taken together, these results suggest that sweet sorghum juice is a potentially suitable feedstock for 3,4-AHBA production by recombinant C. glutamicum. PMID:26409852

  4. Protein-mediated adhesion of the dissimilatory Fe(III)-reducing bacterium Shewanella alga BrY to hydrous ferric oxide

    SciTech Connect

    Caccavo, F. Jr.

    1999-11-01

    The rate and extent of bacterial Fe(III) mineral reduction are governed by molecular-scale interactions between the bacterial cell surface and the mineral surface. These interactions are poorly understood. This study examined the role of surface proteins in the adhesion of Shewanella alga BrY to hydrous ferric oxide (HFO). Enzymatic degradation of cell surface polysaccharides had no effect on cell adhesion to HFO. The proteolytic enzymes Streptomyces griseus protease and chymotrypsin inhibited the adhesion of S. alga BrY cells to HFO through catalytic degradation of surface proteins. Trypsin inhibited S. alga BrY adhesion solely through surface-coating effects. Protease and chymotrypsin also mediated desorption of adhered S. alga BrY cells from HFO while trypsin did not mediate cell desorption. Protease removed a single peptide band that represented a protein with an apparent molecular mass of 50 kDa. Chymotrypsin removed two peptide bands that represented proteins with apparent molecular masses of 60 and 31 kDa. These proteins represent putative HGO adhesion molecules. A. alga BrY adhesion was inhibited by up to 46% when cells were cultured at sub-MICs of chloramphenicol, suggesting that protein synthesis is necessary for adhesion. Proteins extracted from the surface of S. alga BrY cells inhibited adhesion to HFO by up to 41%. A number of these proteins bound specifically to HFO, suggesting that a complex system of surface proteins mediates S. alga BrY adhesion to HFO.

  5. Cetaceans of the Atlantic Frontier, north and west of Scotland

    NASA Astrophysics Data System (ADS)

    Weir, C. R.; Pollock, C.; Cronin, C.; Taylor, S.

    2001-05-01

    Surveys carried out to the north and west of Scotland have recorded 15 species of cetacean between 1979 and 1998. These were fin whale ( Balaenoptera physalus) , sei whale ( B. borealis) , minke whale ( B. acutorostrata) , humpback whale ( Megaptera novaeangliae) , sperm whale ( Physeter macrocephalus) , northern bottlenose whale ( Hyperoodon ampullatus) , Sowerby's beaked whale ( Mesoplodon bidens) , killer whale ( Orcinus orca) , long-finned pilot whale ( Globicephala melas) , Atlantic white-sided dolphin ( Lagenorhynchus acutus) , white-beaked dolphin ( L. albirostris) , Risso's dolphin ( Grampus griseus) , bottlenose dolphin ( Tursiops truncatus) , common dolphin ( Delphinus delphis) and harbour porpoise ( Phocoena phocoena) . Atlantic white-sided dolphin was the most abundant species in the region with a total of 6317 animals recorded. Harbour porpoise was the most frequently sighted cetacean species. The geographical distribution of sightings indicate that cetacean species have varying ecological requirements, with species such as sperm whale, pilot whale and white-sided dolphin favouring deep water off the continental shelf edge, while minke whale, white-beaked dolphin and harbour porpoise were apparently limited to the continental shelf. The diversity of species recorded in the region suggests that the Atlantic Frontier is an important habitat for cetaceans.

  6. Use of In-Biofilm Expression Technology To Identify Genes Involved in Pseudomonas aeruginosa Biofilm Development†

    PubMed Central

    Finelli, Antonio; Gallant, Claude V.; Jarvi, Keith; Burrows, Lori L.

    2003-01-01

    Mature Pseudomonas aeruginosa biofilms form complex three-dimensional architecture and are tolerant of antibiotics and other antimicrobial compounds. In this work, an in vivo expression technology system, originally designed to study virulence-associated genes in complex mammalian environments, was used to identify genes up-regulated in P. aeruginosa grown to a mature (5-day) biofilm. Five unique cloned promoters unable to promote in vitro growth in the absence of purines after recovery from the biofilm environment were identified. The open reading frames downstream of the cloned promoter regions were identified, and knockout mutants were generated. Insertional mutation of PA5065, a homologue of Escherichia coli ubiB, was lethal, while inactivation of PA0240 (a porin homologue), PA3710 (a putative alcohol dehydrogenase), and PA3782 (a homologue of the Streptomyces griseus developmental regulator adpA) had no effect on planktonic growth but caused defects in biofilm formation in static and flowing systems. In competition experiments, mutants demonstrated reduced fitness compared with the parent strain, comprising less than 0.0001% of total biofilm cells after 5 days. Therefore, using in-biofilm expression technology, we have identified novel genes that do not affect planktonic growth but are important for biofilm formation, development, and fitness. PMID:12700249

  7. Evolutionary Relations of Hexanchiformes Deep-Sea Sharks Elucidated by Whole Mitochondrial Genome Sequences

    PubMed Central

    Tanaka, Keiko; Tomita, Taketeru; Suzuki, Shingo; Hosomichi, Kazuyoshi; Sano, Kazumi; Doi, Hiroyuki; Kono, Azumi; Inoko, Hidetoshi; Kulski, Jerzy K.; Tanaka, Sho

    2013-01-01

    Hexanchiformes is regarded as a monophyletic taxon, but the morphological and genetic relationships between the five extant species within the order are still uncertain. In this study, we determined the whole mitochondrial DNA (mtDNA) sequences of seven sharks including representatives of the five Hexanchiformes, one squaliform, and one carcharhiniform and inferred the phylogenetic relationships among those species and 12 other Chondrichthyes (cartilaginous fishes) species for which the complete mitogenome is available. The monophyly of Hexanchiformes and its close relation with all other Squaliformes sharks were strongly supported by likelihood and Bayesian phylogenetic analysis of 13,749 aligned nucleotides of 13 protein coding genes and two rRNA genes that were derived from the whole mDNA sequences of the 19 species. The phylogeny suggested that Hexanchiformes is in the superorder Squalomorphi, Chlamydoselachus anguineus (frilled shark) is the sister species to all other Hexanchiformes, and the relations within Hexanchiformes are well resolved as Chlamydoselachus, (Notorynchus, (Heptranchias, (Hexanchus griseus, H. nakamurai))). Based on our phylogeny, we discussed evolutionary scenarios of the jaw suspension mechanism and gill slit numbers that are significant features in the sharks. PMID:24089661

  8. Building hierarchical models of avian distributions for the State of Georgia

    USGS Publications Warehouse

    Howell, J.E.; Peterson, J.T.; Conroy, M.J.

    2008-01-01

    To predict the distributions of breeding birds in the state of Georgia, USA, we built hierarchical models consisting of 4 levels of nested mapping units of decreasing area: 90,000 ha, 3,600 ha, 144 ha, and 5.76 ha. We used the Partners in Flight database of point counts to generate presence and absence data at locations across the state of Georgia for 9 avian species: Acadian flycatcher (Empidonax virescens), brownheaded nuthatch (Sitta pusilla), Carolina wren (Thryothorus ludovicianus), indigo bunting (Passerina cyanea), northern cardinal (Cardinalis cardinalis), prairie warbler (Dendroica discolor), yellow-billed cuckoo (Coccyxus americanus), white-eyed vireo (Vireo griseus), and wood thrush (Hylocichla mustelina). At each location, we estimated hierarchical-level-specific habitat measurements using the Georgia GAP Analysis18 class land cover and other Geographic Information System sources. We created candidate, species-specific occupancy models based on previously reported relationships, and fit these using Markov chain Monte Carlo procedures implemented in OpenBugs. We then created a confidence model set for each species based on Akaike's Information Criterion. We found hierarchical habitat relationships for all species. Three-fold cross-validation estimates of model accuracy indicated an average overall correct classification rate of 60.5%. Comparisons with existing Georgia GAP Analysis models indicated that our models were more accurate overall. Our results provide guidance to wildlife scientists and managers seeking predict avian occurrence as a function of local and landscape-level habitat attributes.

  9. Differentiations of Chitin Content and Surface Morphologies of Chitins Extracted from Male and Female Grasshopper Species

    PubMed Central

    Kaya, Murat; Lelešius, Evaldas; Nagrockaitė, Radvilė; Sargin, Idris; Arslan, Gulsin; Mol, Abbas; Baran, Talat; Can, Esra; Bitim, Betul

    2015-01-01

    In this study, we used Fourier transform infrared spectroscopy (FT-IR), elemental analysis (EA), thermogravimetric analysis (TGA), X-ray diffractometry (XRD), and scanning electron microscopy (SEM) to investigate chitin structure isolated from both sexes of four grasshopper species. FT-IR, EA, XRD, and TGA showed that the chitin was in the alpha form. With respect to gender, two main differences were observed. First, we observed that the quantity of chitin was greater in males than in females and the dry weight of chitin between species ranged from 4.71% to 11.84%. Second, using SEM, we observed that the male chitin surface structure contained 25 – 90nm wide nanofibers and 90 – 250 nm nanopores, while no pores or nanofibers were observed in the chitin surface structure of the majority of females (nanofibers were observed only in M. desertus females). In contrast, the elemental analysis, thermal properties, and crystalline index values for chitin were similar in males and females. Also, we carried out enzymatic digestion of the isolated chitins using commercial chitinase from Streptomyces griseus. We observed that there were no big differences in digestion rate of the chitins from both sexes and commercial chitin. The digestion rates were for grasshoppers’ chitins; 88.45–95.48% and for commercial chitin; 94.95%. PMID:25635814

  10. Niche dynamics of shorebirds in Delaware Bay: Foraging behavior, habitat choice and migration timing

    NASA Astrophysics Data System (ADS)

    Novcic, Ivana

    2016-08-01

    Niche differentiation through resource partitioning is seen as one of the most important mechanisms of diversity maintenance contributing to stable coexistence of different species within communities. In this study, I examined whether four species of migrating shorebirds, dunlins (Calidris alpina), semipalmated sandpipers (Calidris pusilla), least sandpipers (Calidris minutilla) and short-billed dowitchers (Limnodromus griseus), segregate by time of passage, habitat use and foraging behavior at their major stopover in Delaware Bay during spring migration. I tested the prediction that most of the separation between morphologically similar species will be achieved by differential migration timing. Despite the high level of overlap along observed niche dimensions, this study demonstrates a certain level of ecological separation between migrating shorebirds. The results of analyses suggest that differential timing of spring migration might be the most important dimension along which shorebird species segregate while at stopover in Delaware Bay. Besides differences in time of passage, species exhibited differences in habitat use, particularly least sandpipers that foraged in vegetated areas of tidal marshes more frequently than other species, as well as short-billed dowitchers that foraged in deeper water more often than small sandpipers did. Partitioning along foraging techniques was less prominent than segregation along temporal or microhabitat dimensions. Such ranking of niche dimensions emphasizes significance of temporal segregation of migratory species - separation of species by time of passage may reduce the opportunity for interspecific aggressive encounters, which in turn can have positive effects on birds' time and energy budget during stopover period.

  11. Cloning and analysis of a gene cluster from Streptomyces coelicolor that causes accelerated aerial mycelium formation in Streptomyces lividans.

    PubMed Central

    Ma, H; Kendall, K

    1994-01-01

    We describe the cloning and analysis of two overlapping DNA fragments from Streptomyces coelicolor that cause aerial mycelium to appear more rapidly than usual when introduced into Streptomyces lividans on a low-copy-number plasmid vector. Colonies of S. lividans TK64 harboring either clone produce visible aerial mycelia after only 48 h of growth, rather than the usual 72 to 96 h. From deletion and sequence analysis, this rapid aerial mycelium (Ram) phenotype appears to be due to a cluster of three genes that we have designated ramA, ramB, and ramR. Both ramA and ramB potentially encode 65-kDa proteins with homology to ATP-dependent membrane-translocating proteins. A chromosomal ramB disruption mutant of S. lividans was found to be severely defective in aerial mycelium formation. ramR could encode a 21-kDa protein with significant homology to the UhpA subset of bacterial two-component response regulator proteins. The overall organization and potential proteins encoded by the cloned DNA suggest that this is the S. coelicolor homolog of the amf gene cluster that has been shown to be important for aerial mycelium formation in Streptomyces griseus. However, despite the fact that the two regions probably have identical functions, there is relatively poor homology between the two gene clusters at the DNA sequence level. Images PMID:8206859

  12. Evaluation of squirrels (Rodentia: Sciuridae) as ecologically significant hosts for Anaplasma phagocytophilum in California.

    PubMed

    Nieto, Nathan C; Foley, Janet E

    2008-07-01

    Granulocytic anaplasmosis (GA), caused by Anaplasma phagocytophilum, is a potentially fatal, emerging rickettsial disease of humans, domestic animals, and wildlife. The purpose of this study was to determine whether sciurids from multiple areas of northern California were infested with ticks or exposed to or infected with A. phagocytophilum using polymerase chain reaction (PCR) and indirect-fluorescent antibody (IFA) serology. Sciurids of nine different tree- and ground-dwelling species were assessed: arboreal squirrels (western and eastern gray squirrels, Sciurus griseus and S. carolinensis, and Douglas squirrels, Tamiasciurus douglasii) but not northern flying squirrels (Glaucomys sabrinus) had greater evidence of exposure and current infection than did semiarboreal or ground dwelling sciurids (California ground squirrels, Spermophilus beecheyi, and chipmunks, Tamias spp.). Western gray squirrels had the most extensive exposure (70.7% seroprevalence and 12.1% PCR prevalence). Positive squirrels were identified in all regions where squirrels were collected. A logistic regression identified being a western gray squirrel (OR = 20.5, P = 2.95 X 10(-8)) and from the north coastal region of California (OR = 9.052, P = 1.41 X 10(-6)) as having the highest risk of exposure to A. phagocytophilum. Five of nine sciurid species had evidence of infestation with Ixodes pacificus or I. spinipalpis that could vector A. phagocytophilum. Extensive exposure from multiple areas suggests sciurids may be important in the maintenance of GA in California and indicates that studies of reservoir competence of these species are warranted. PMID:18714881

  13. Production of N-Acetyl-d-glucosamine from Mycelial Waste by a Combination of Bacterial Chitinases and an Insect N-Acetyl-d-glucosaminidase.

    PubMed

    Zhu, Weixing; Wang, Di; Liu, Tian; Yang, Qing

    2016-09-01

    N-Acetyl-d-glucosamine (GlcNAc) has great potential to be used as a food additive and medicine. The enzymatic degradation of chitin-containing biomass for producing GlcNAc is an eco-friendly approach but suffers from a high cost. The economical efficiency can be improved by both optimizing the member and ratio of the chitinolytic enzymes and using new inexpensive substrates. To address this, a novel combination of bacterial and insect chitinolytic enzymes was developed in this study to efficiently produce GlcNAc from the mycelia of Asperillus niger, a fermentation waste. This enzyme combination contained three bacterial chitinases (chitinase A from Serratia marcescens (SmChiA), SmChiB, SmChiC) and one insect N-acetyl-d-glucosaminidase from Ostrinia furnacalis (OfHex1) in a ratio of 39.1% of SmChiA, 26.7% of SmChiB, 32.9% of SmChiC, and 1.3% of OfHex1. A yield of 6.3 mM (1.4 mg/mL) GlcNAc with a purity of 95% can be obtained from 10 mg/mL mycelial powder in 24 h. The enzyme combination reported here exhibited 5.8-fold higher hydrolytic activity over the commercial chitinase preparation derived from Streptomyces griseus. PMID:27546481

  14. Shearwaters as ecosystem indicators: Towards fishery-independent metrics of fish abundance in the California Current

    NASA Astrophysics Data System (ADS)

    Lyday, Shannon E.; Ballance, Lisa T.; Field, David B.; David Hyrenbach, K.

    2015-06-01

    Shearwaters are ideal for monitoring ocean conditions in the California Current because these predators are abundant, conspicuous, and responsive to oceanographic variability. Herein we evaluated black-vented (Puffinus opisthomelas), Buller's (P. bulleri), flesh-footed (P. carneipes), pink-footed (P. creatopus), short-tailed (P. tenuirostris), and sooty (P. griseus) shearwaters as fishery-independent indicators of predatory or prey fish availability. We analyzed four years (1996, 2001, 2005, 2008) of monthly (August-November) National Oceanic and Atmospheric Administration seabird surveys, and United States Geological Survey Pacific Coast Fisheries Database catch, from the California coast to 200 nm offshore. An ordination of shearwater abundance and fish catch revealed that the shearwaters and 11 fish/squid species were significantly correlated with one or more of three principal components, which explained 86% of the variation and revealed distinct species assemblages. We evaluated multiple linear regression models for 19 fisheries using five shearwater metrics: density, aggregation, and behavior (traveling, stationary, feeding), three oceanographic indices, and latitude. Eight of these models had a shearwater metric as the primary predictor. In particular, feeding black-vented shearwater abundance explained 75% of dolphinfish (Coryphaena hippurus) longline catch. This research illustrates the utility of shearwaters as ecosystem indicators, with direct application for predicting fishery catch of commercial importance.

  15. Combining Breeding Bird Survey and distance sampling to estimate density of migrant and breeding birds

    USGS Publications Warehouse

    Somershoe, S.G.; Twedt, D.J.; Reid, B.

    2006-01-01

    We combined Breeding Bird Survey point count protocol and distance sampling to survey spring migrant and breeding birds in Vicksburg National Military Park on 33 days between March and June of 2003 and 2004. For 26 of 106 detected species, we used program DISTANCE to estimate detection probabilities and densities from 660 3-min point counts in which detections were recorded within four distance annuli. For most species, estimates of detection probability, and thereby density estimates, were improved through incorporation of the proportion of forest cover at point count locations as a covariate. Our results suggest Breeding Bird Surveys would benefit from the use of distance sampling and a quantitative characterization of habitat at point count locations. During spring migration, we estimated that the most common migrant species accounted for a population of 5000-9000 birds in Vicksburg National Military Park (636 ha). Species with average populations of 300 individuals during migration were: Blue-gray Gnatcatcher (Polioptila caerulea), Cedar Waxwing (Bombycilla cedrorum), White-eyed Vireo (Vireo griseus), Indigo Bunting (Passerina cyanea), and Ruby-crowned Kinglet (Regulus calendula). Of 56 species that bred in Vicksburg National Military Park, we estimated that the most common 18 species accounted for 8150 individuals. The six most abundant breeding species, Blue-gray Gnatcatcher, White-eyed Vireo, Summer Tanager (Piranga rubra), Northern Cardinal (Cardinalis cardinalis), Carolina Wren (Thryothorus ludovicianus), and Brown-headed Cowbird (Molothrus ater), accounted for 5800 individuals.

  16. Biotransformation of dihydroisosteviol and the effects of transformed products on steroidogenic gene expressions.

    PubMed

    Chang, Shwu-Fen; Yang, Li-Ming; Huang, Tsurng-Juhn; Chen, Chin-Yang; Sheu, Shiow-Yunn; Liu, Pan-Chun; Lin, Shwu-Jiuan

    2013-11-01

    The biotransformation of dihydroisosteviol with Absidia pseudocylindrospora ATCC 24169, Streptomyces griseus ATCC 10137, Mucor recurvatus MR36, and Aspergillus niger BCRC 31130 yielded 15 metabolites, eight of which were previously unknown. Structures of metabolites were established by 2D NMR techniques and HRMS data, two of which were further corroborated by chemical means, and another via single-crystal X-ray diffraction analysis. Subsequently, two steroidogenic cell lines (Y-1 mouse adrenal tumor and MA-10 mouse Leydig tumor cells) were used in a reverse transcription-PCR analysis to assess the effects of all compounds on steroidogenic gene expressions using forskolin as a positive control. The tested gene expressions included steroidogenic factor-1 (SF-1), steroidogenic acute regulatory protein (StAR), and cytochrome P450 side-chain cleavage (P450scc) enzyme. Gene expression profiles showed that ten of the tested compounds effectively suppressed P450SCC mRNA expression in both Y-1 and MA-10 cells. Several induced SF-1 gene expression and two enhanced StAR gene expression in Y-1 cells. By contrast, in MA-10 cells, one compound effectively suppressed StAR mRNA expression, whereas for others effectively suppressed SF-1 gene expression. The results suggest that analogs of dihydroisosteviol can be potential modulators to alter steroidogenic gene expressions and subsequent enzyme activities. PMID:23948258

  17. A novel detergent-stable solvent-tolerant serine thiol alkaline protease from Streptomyces koyangensis TN650.

    PubMed

    Ben Elhoul, Mouna; Zaraî Jaouadi, Nadia; Rekik, Hatem; Bejar, Wacim; Boulkour Touioui, Souraya; Hmidi, Maher; Badis, Abdelmalek; Bejar, Samir; Jaouadi, Bassem

    2015-08-01

    An alkaline proteinase (STAP) was produced from strain TN650 isolated from a Tunisian off-shore oil field and assigned as Streptomyces koyangensis strain TN650 based on physiological and biochemical properties and 16S rRNA gene sequencing. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS) analysis revealed that the purified enzyme was a monomer with a molecular mass of 45125.17-Da. The enzyme had an NH2-terminal sequence of TQSNPPSWGLDRIDQTTAFTKACSIKY, thus sharing high homology with those of Streptomyces proteases. The results showed that this protease was completely inhibited by phenylmethanesulfonyl fluoride (PMSF), diiodopropyl fluorophosphates (DFP), and partially inhibited by 5,5-dithio-bis-(2-nitro benzoic acid) (DTNB), which strongly suggested its belonging to the serine thiol protease family. Using casein as a substrate, the optimum pH and temperature values for protease activity were pH 10 and 70 °C, respectively. The protease was stable at pH 7-10 and 30-60 °C for 24 h. STAP exhibited high catalytic efficiency, significant detergent stability, and elevated organic solvent resistance compared to the SG-XIV proteases from S. griseus and KERAB from Streptomyces sp. AB1. The stap gene encoding STAP was isolated, and its DNA sequence was determined. These properties make STAP a potential candidate for future application in detergent formulations and non-aqueous peptide biocatalysis. PMID:26056991

  18. Total number and volume of Von Economo neurons in the cerebral cortex of cetaceans.

    PubMed

    Butti, Camilla; Sherwood, Chet C; Hakeem, Atiya Y; Allman, John M; Hof, Patrick R

    2009-07-10

    Von Economo neurons (VENs) are a type of large, layer V spindle-shaped neurons that were previously described in humans, great apes, elephants, and some large-brained cetaceans. Here we report the presence of Von Economo neurons in the anterior cingulate (ACC), anterior insular (AI), and frontopolar (FP) cortices of small odontocetes, including the bottlenose dolphin (Tursiops truncatus), the Risso's dolphin (Grampus griseus), and the beluga whale (Delphinapterus leucas). The total number and volume of VENs and the volume of neighboring layer V pyramidal neurons and layer VI fusiform neurons were obtained by using a design-based stereologic approach. Two humpback whale (Megaptera novaeangliae) brains were investigated for comparative purposes as representatives of the suborder Mysticeti. Our results show that the distribution of VENs in these cetacean species is comparable to that reported in humans, great apes, and elephants. The number of VENs in these cetaceans is also comparable to data available from great apes, and stereologic estimates indicate that VEN volume follows in these cetacean species a pattern similar to that in hominids, the VENs being larger than neighboring layer V pyramidal cells and conspicuously larger than fusiform neurons of layer VI. The fact that VENs are found in species representative of both cetacean suborders in addition to hominids and elephants suggests that these particular neurons have appeared convergently in phylogenetically unrelated groups of mammals possibly under the influence of comparable selective pressures that influenced specifically the evolution of cortical domains involved in complex cognitive and social/emotional processes. PMID:19412956

  19. Prion search and cellular prion protein expression in stranded dolphins.

    PubMed

    Di Guardo, G; Cocumelli, C; Meoli, R; Barbaro, K; Terracciano, G; Di Francesco, C E; Mazzariol, S; Eleni, C

    2012-01-01

    The recent description of a prion disease (PD) case in a free-ranging bottlenose dolphin (Tursiops truncatus) prompted us to carry out an extensive search for the disease-associated isoform (PrPSc) of the cellular prion protein (PrPC) in the brain and in a range of lymphoid tissues from 23 striped dolphins (Stenella coeruleoalba), 5 bottlenose dolphins and 2 Risso s dolphins (Grampus griseus) found stranded between 2007 and 2012 along the Italian coastline. Three striped dolphins and one bottlenose dolphin showed microscopic lesions of encephalitis, with no evidence of spongiform brain lesions being detected in any of the 30 free-ranging cetaceans investigated herein. Nevertheless, we could still observe a prominent PrPC immunoreactivity in the brain as well as in lymphoid tissues from these dolphins. Although immunohistochemical and Western blot investigations yielded negative results for PrPSc deposition in all tissues from the dolphins under study, the reported occurrence of a spontaneous PD case in a wild dolphin is an intriguing issue and a matter of concern for both prion biology and intra/inter-species transmissibility, as well as for cetacean conservation medicine. PMID:23034277

  20. Streptomyces beta-alanine:alpha-ketoglutarate aminotransferase, a novel omega-amino acid transaminase. Purification, crystallization, and enzymologic properties.

    PubMed

    Yonaha, K; Suzuki, K; Toyama, S

    1985-03-25

    An enzyme which catalyzes the transamination of beta-alanine with alpha-ketoglutarate was purified to homogeneity from Streptomyces griseus IFO 3102 and crystallized. Molecular weight of the enzyme was found to be 185,000 +/- 10,000 by a gel-filtration method. The enzyme consists of four subunits identical in molecular weight (51,000 +/- 1,000). The transaminase is composed of 483 amino acids/subunit containing 7 and 8 residues of half-cystine and methionine, respectively. The enzyme exhibits absorption maxima at 278 and 415 nm. The pyridoxal 5'-phosphate content was determined to be 4 mol/mol of enzyme. The enzyme catalyzes transamination of omega-amino acids including taurine and hypotaurine. beta-Alanine and DL-beta-aminoisobutyrate served as a good amino donor; the Michaelis constants are 8.0 and 12.5 mM, respectively. alpha-Ketoglutarate is the only amino acceptor (Km = 4.0 mM); pyruvate and oxalacetate are inactive. Based on the substrate specificity, the terminology of beta-alanine:alpha-ketoglutarate transaminase is proposed for the enzyme. Carbonyl reagents, HgCl2,DL-gabaculine, and alpha-fluoro-beta-alanine strongly inhibited the enzyme. PMID:3972825

  1. Fluorescent microbead-based immunoassay for anti-Erysipelothrix rhusiopathiae antibody detection in cetaceans.

    PubMed

    Melero, Mar; Giménez-Lirola, Luis G; Rubio-Guerri, Consuelo; Crespo-Picazo, José Luis; Sierra, Eva; García-Párraga, Daniel; García-Peña, Francisco Javier; Arbelo, Manuel; Álvaro, Teresa; Valls, Mónica; Sánchez-Vizcaíno, José Manuel

    2016-01-13

    A fluorescent microbead-based immunoassay (FMIA) for detection of anti-Erysipelothrix rhusiopathiae antibodies in pigs was adapted for use in cetaceans. The FMIA was validated and adjusted using serum samples from 10 vaccinated captive bottlenose dolphins Tursiops truncatus collected between 1 and 13 mo after immunization. The technique was then used to analyze specimens from 15 free-ranging cetaceans stranded alive on the Valencian Mediterranean coast between 2006 and 2014: 11 striped dolphins Stenella coeruleoalba, 3 Risso's dolphins Grampus griseus and 1 bottlenose dolphin Tursiops truncatus. One of these wild animals was confirmed to have died from E. rhusiopathiae septicemia, but no anti-E. rhusiopathiae antibodies were detected in its serum, pericardial fluid or milk samples. Another free-ranging individual, which lacked any signs or lesions that might be indicative of E. rhusiopathiae infection, showed high fluorescence intensity similar to that measured in captive dolphins at 6-13 mo after vaccination. These results suggest that this animal underwent an E. rhusiopathiae infection several months before stranding. The findings in the present study suggest that FMIA can be useful for detecting anti-E. rhusiopathiae antibodies in cetaceans, and its application to free-ranging animals is particularly interesting because of the great value of these specimens. Furthermore, the FMIA can be multiplexed to allow the determination of up to 100 analytes per sample in a single well, thereby reducing the cost, time and sample volume needed. PMID:26758657

  2. Prey preferences among the community of deep-diving odontocetes from the Bay of Biscay, Northeast Atlantic

    NASA Astrophysics Data System (ADS)

    Spitz, Jérôme; Cherel, Yves; Bertin, Stéphane; Kiszka, Jeremy; Dewez, Alexandre; Ridoux, Vincent

    2011-03-01

    Long-finned pilot whales ( Globicephala melas), Risso's dolphins ( Grampus griseus), melon-headed whales ( Peponocephala electra), Cuvier's beaked whales ( Ziphius cavirostris), Sowerby's beaked whales ( Mesoplodon bidens), northern bottlenose whales ( Hyperoodon ampullatus), sperm whales ( Physeter macrocephalus), dwarf sperm whales ( Kogia sima) and pygmy sperm whales ( Kogia breviceps) make up the large community of deep-diving odontocetes occurring off the Bay of Biscay, northeast Atlantic. The ecology of these toothed cetaceans is poorly documented worldwide. The present study described their prey preferences from stomach content analysis and showed resource partitioning within the assemblage. The majority of the species appeared to be mostly teutophageous. Fish was an important food source only for the Sowerby's beaked whale and, to a lesser extent, for the long-finned pilot whale. In terms of foraging habitats inferred from prey composition, either pelagic oceanic or demersal neritic habitats were exploited by toothed whales in the Bay of Biscay, with only the long-finned pilot whale foraging in the two habitats. Finally, with more than 14,000 identified cephalopods from 39 species, the present study highlighted also the poorly known deep-sea cephalopod community off the Bay of Biscay using top predators as biological samplers.

  3. Bacterial single-stranded DNA-binding proteins are phosphorylated on tyrosine

    PubMed Central

    Mijakovic, Ivan; Petranovic, Dina; Macek, Boris; Cepo, Tina; Mann, Matthias; Davies, Julian; Jensen, Peter R.; Vujaklija, Dusica

    2006-01-01

    Single-stranded DNA-binding proteins (SSBs) are required for repair, recombination and replication in all organisms. Eukaryotic SSBs are regulated by phosphorylation on serine and threonine residues. To our knowledge, phosphorylation of SSBs in bacteria has not been reported. A systematic search for phosphotyrosine-containing proteins in Streptomyces griseus by immunoaffinity chromatography identified bacterial SSBs as a novel target of bacterial tyrosine kinases. Since genes encoding protein-tyrosine kinases (PTKs) have not been recognized in streptomycetes, and SSBs from Streptomyces coelicolor (ScSSB) and Bacillus subtilis (BsSSB) share 38.7% identity, we used a B.subtilis protein-tyrosine kinase YwqD to phosphorylate two cognate SSBs (BsSSB and YwpH) in vitro. We demonstrate that in vivo phosphorylation of B.subtilis SSB occurs on tyrosine residue 82, and this reaction is affected antagonistically by kinase YwqD and phosphatase YwqE. Phosphorylation of B.subtilis SSB increased binding almost 200-fold to single-stranded DNA in vitro. Tyrosine phosphorylation of B.subtilis, S.coelicolor and Escherichia coli SSBs occured while they were expressed in E.coli, indicating that tyrosine phosphorylation of SSBs is a conserved process of post-translational modification in taxonomically distant bacteria. PMID:16549871

  4. Resynthesis of reactive site peptide bond and temporary inhibition of Streptomyces metalloproteinase inhibitor.

    PubMed

    Seeram, S S; Hiraga, K; Oda, K

    1997-10-01

    Streptomyces metalloproteinase inhibitor (SMPI) is a small proteinaceous inhibitor which inhibits metalloproteinases such as thermolysin (Ki =1.14 x 10(-10) M). When incubated with the enzyme, it is gradually hydrolyzed at the Cys64-Val65 peptide bond, which was identified as the reactive site by mutational analysis. To achieve a further understanding of the inhibition mechanism, we attempted to resynthesize the cleaved reactive site by using the enzyme catalytic action. The native inhibitor was resynthesized from the modified inhibitor (Ki =2.18 x 10(-8) M) by incubation with a catalytic amount of thermolysin under the same conditions as used for hydrolysis (pH 7.5, 25 degrees C), suggesting that SMPI follows the standard mechanism of inhibition of serine proteinase inhibitors. Temporary inhibition was observed when the native inhibitor and thermolysin were incubated at a 1:100 (mol/mol) enzyme-inhibitor ratio at 37 degrees C. SMPI showed temporary inhibition towards all the enzymes it inhibited. The inhibitory spectrum of SMPI was analyzed with various metalloproteinases based on the Ki values and limited proteolysis patterns. Pseudomonas elastase and Streptomyces griseus metalloproteinase II formed more stable complexes and showed much lower Ki values (approximately 2 pM) than thermolysin. In the limited proteolysis experiments weak inhibitors were degraded by the enzymes. SMPI did not inhibit almelysin, Streptomyces caespitosus neutral proteinase or matrix metalloproteinases. SMPI specifically inhibits metalloproteinases which are sensitive to phosphoramidon. PMID:9399583

  5. Sequence analysis of the aminoacylase-1 family. A new proposed signature for metalloexopeptidases.

    PubMed

    Biagini, A; Puigserver, A

    2001-03-01

    The amino acid sequence analysis of the human and porcine aminoacylases-1, the carboxypeptidase S precursor from Saccharomyces cerevisiae, the succinyl-diaminopimelate desuccinylase from Escherichia coli, Haemophilus influenzae and Corynebacterium glutamicum, the acetylornithine deacetylase from Escherichia coli and Dictyostelium discoideum and the carboxypeptidase G(2) precursor from Pseudomonas strain, using the Basic Local Alignment Search Tool (BLAST) and the Position-Specific Iterated BLAST (PSI-BLAST), allowed us to suggest that all these enzymes, which share common functional and biochemical features, belong to the same structural family. The three amino acid blocks which were found to be highly conserved, using the CLUSTAL W program, could be assigned to the catalytic active site, based on the general three-dimensional structure of the carboxypeptidase G(2) from the Pseudomonas strain precursor. Six additional proteins with the same signature have been retrieved after performing two successive PSI-BLAST iterations using the sequence of the conserved motif, namely Lactobacillus delbrueckii aminoacyl-histidine dipeptidase, Streptomyces griseus aminopeptidase, Saccharomyces cerevisiae aminopeptidase Y precursor, two Bacillus stearothermophilus N-carbamyl-L-amino acid amidohydrolases and Pseudomonas sp. hydantoin utilization protein C. The three conserved amino acid motifs corresponded to the following blocks: (i) [S, G, A]-H-x-D-x-V; (ii) G-x-x-D; and (iii) x-E-E. This new sequence signature is clearly different from that commonly reported in the literature for proteins belonging to the ArgE/DapE/CPG2/YscS family. PMID:11250542

  6. Recombinant expression, biochemical characterization and stabilization through proteolysis of an L-glutamate oxidase from Streptomyces sp. X-119-6.

    PubMed

    Arima, Jiro; Tamura, Takashi; Kusakabe, Hitoshi; Ashiuchi, Makoto; Yagi, Toshiharu; Tanaka, Hidehiko; Inagaki, Kenji

    2003-12-01

    L-glutamate oxidase (LGOX) from Streptomyces sp. X-119-6 is a protein of 150 kDa that has hexamer structure alpha2beta2gamma2. The gene encoding LGOX was cloned and heterologously expressed in Escherichia coli. LGOX isolated from the E. coli transformant had the structure of a one chain polypeptide. Although the recombinant LGOX exhibited catalytic activity, it was inferior to the LGOX isolated from Streptomyces sp. X-119-6 in catalytic efficiency. The recombinant LGOX exhibited low thermostability compared to the LGOX isolated from Streptomyces sp. X-119-6 and was an aggregated form. Proteolysis of the recombinant LGOX with the metalloendopeptidase from Streptomyces griseus (Sgmp) improved its catalytic efficiency at various pH. Furthermore, the Sgmp-treated recombinant LGOX had a subunit structure of alpha2beta2gamma2 and nearly the same enzymological character as the LGOX isolated from Streptomyces sp. X-119-6. A higher molecular species observed for the recombinant LGOX was not detected for the Sgmp-treated recombinant LGOX. These results prove that proteolysis by Sgmp is involved in the stabilization of the recombinant LGOX. PMID:14769868

  7. Non-specific depolymerization of chitosan by pronase and characterization of the resultant products.

    PubMed

    Kumar, Acharya B Vishu; Gowda, Lalitha R; Tharanathan, Rudrapatnam N

    2004-02-01

    Pronase (type XXV serine protease from Streptomyces griseus) efficiently depolymerizes chitosan, a linear beta-->1,4-linked polysaccharide of 2-amino-deoxyglucose and 2-amino-2-N-acetylamino-D-glucose, to low-molecular weight chitosans (LMWC), chito-oligomers (degree of polymerization, 2-6) and monomer. The maximum depolymerization occurred at pH 3.5 and 37 degrees C, and the reaction obeyed Michaelis-Menten kinetics with a Km of 5.21 mg.mL(-1) and Vmax of 138.55 nmoles.min(-1).mg(-1). The molecular mass of the major product, LMWC, varied between 9.0 +/- 0.5 kDa depending on the reaction time. Scanning electron microscopy of LMWC showed an approximately eightfold decrease in particle size and characterization by infrared spectroscopy, circular dichroism, X-ray diffractometry and 13C-NMR revealed them to possess a lower degree of acetylation, hydration and crystallinity compared to chitosan. Chitosanolysis by pronase is an alternative and inexpensive method to produce a variety of chitosan degradation products that have wide and varied biofunctionalities. PMID:14764087

  8. The role of Cu(I)-thiolate clusters during the proteolysis of Cu-thionein.

    PubMed

    Weser, U; Mutter, W; Hartmann, H J

    1986-03-01

    Rat liver Cu,Zn-[35S]thionein and yeast Cu-thionein were subjected to proteolysis in vitro using equilibrium dialysis. The partially copper-loaded vertebrate thionein (2-7 Cu/mol) was affected by different proteases including thermolysin, proteinase K, protease from Streptomyces griseus and lysosomal enzymes. Unlike the 2Cu-thionein the respective 7Cu-thiolate-centred metallothionein was hardly proteolytically digested. In contrast to fully copper-loaded native yeast Cu-thionein both the H2O2-oxidized and the metal-free protein were effectively cleaved in the presence of proteinase K. It is important to realize that the native Cu(I)-thiolate chromophore survives the proteolytic attack. When the copper-sulphur bonding is broken and the same amount of copper is unspecifically bound to the thionein portion, proteolysis proceeds identically with respect to the rate observed in the presence of the apoprotein. The unsuccessful proteolysis of native Cu-thionein is not attributable to a simple copper-dependent inhibition of the proteinases. It is suggested that prior to proteolysis the copper-sulphur clusters must be destroyed. PMID:3081372

  9. Anoikis-resistant MDCK cells carrying susceptibilities to TNF-alpha and verotoxin that are suitable for influenza virus cultivation.

    PubMed

    Tsutsumi, Reiko; Fujisaki, Shigemi; Shozushima, Masanori; Saito, Koichi; Sato, Shigehiro

    2006-10-01

    Madin-Darby canine kidney (MDCK) cells were originally anchorage-dependent epithelial cells. Here, we have isolated a novel MDCK-derived cell population, termed 6 M-4, by means of culturing MDCK cells in suspension for nearly 6 months in the presence of Streptomyces griseus metalloendopeptidase (MEP). The isolated cells showed unique proliferation characteristics, which differed from parental MDCK cells. They proliferated adherently on a polystyrene matrix, but proliferated non-adherently both in the presence of MEP and on a non-adhesive matrix coated with poly 2-methacryloyloxyethyl phosphorylcholine (MPC). The 6 M-4 cells consisted of at least two cell types. One type, termed 6 M-4-TR7, would not grow in soft agar and showed a novel phenotype in that the cells were susceptible to both TNF-alpha and verotoxin 1 (VT1). In addition, the isolated adhesion-independent cells sustained epithelial traits of parental MDCK cells. We further show that these MDCK-derivative cells are suitable for influenza virus cultivation. Hemagglutination (HA) titers of influenzaviruses A and B were increased in the suspension culture of 6 M-4-TR7 cells supplemented with the MEP in comparison to adherently growing cells in the presence of trypsin. PMID:19002866

  10. Disulfide bridge structure of ascidian trypsin inhibitor I: similarity to Kazal-type inhibitors.

    PubMed

    Kumazaki, T; Ishii, S

    1990-03-01

    The primary structures of ascidian trypsin inhibitors (iso-inhibitors I and II) were reported in the preceding paper (Kumazaki, T. et al. (1990) J. Biochem. 107, 409-413). Both of them have eight half-cystines in a molecule composed of 55 amino acid residues with a sequence showing no extensive homology to other known protease inhibitors. To locate the four disulfide bridges in the molecule, native inhibitor I was digested with thermolysin to yield cystine-containing peptides. The peptides were separated from each other by reversed-phase HPLC. A core peptide still containing six closely located half-cystines (e.g. -Cys-Arg-Cys and -Cys-Cys-) was further digested with Streptomyces griseus trypsin for cleavage of the Arg-Cys bond. On the other hand, the Cys-Cys bond was split by applying manual Edman degradation to the core peptide. Amino acid composition analyses of the resulting cystine peptides allowed us to define the whole disulfide bridge structure in the parent molecule. The topological relation between the disulfide loops and the reactive site suggested that the ascidian trypsin inhibitor may be classified as a member of the Kazal-type inhibitor family. PMID:2111316

  11. Application of bimane-peptide substrates to spectrofluorometric assays of metalloendopeptidases.

    PubMed

    Kajiwara, K; Kumazaki, T; Sato, E; Kanaoka, Y; Ishii, S

    1991-09-01

    A spectrofluorometric method for sensitive determination of metalloendopeptidase activity has been developed by using a bimane-peptide containing a tryptophan residue, i.e. 1,7-dioxo-2,5,6-trimethyl-1H,7H-pyrazolo[1,2-alpha]pyrazol-3-yl-methyl- thiomethylcarbonyl-phenylalanyl-tryptophanyl-leucine (Bim-SCH2CO-Phe-Trp-Leu-OH). Such an "intramolecularly quenched" substrate was originally designed for a sensitive assay of angiotensin I converting enzyme (ACE) [Sato, E. et al. (1989) Chem. Pharm. Bull. 37, 145-147]. All the typical metalloendopeptidases tested, such as thermolysin, Pseudomonas aeruginosa (Ps.) elastase, Streptomyces griseus metalloendopeptidases I and II (SGMPI and SGMPII), and alkinonase A, a metalloendopeptidase from Streptomyces violaceorectus, cleaved this substrate strictly at a Phe-Trp bond, leading to a marked increase in fluorescence. Kinetic parameters of the enzymatic hydrolyses of five kinds of analogous bimane substrates were compared to examine how the nature of neighboring amino acid residues on either side of the cleavable bond affects the catalytic efficiency of each of the metalloendopeptidases. Bim-SCH2CO-Phe-Trp-Leu-OH was most efficiently hydrolyzed by all of these enzymes. The use of this substrate made it possible to determine minute amounts of metalloendopeptidases, especially those originating from Streptomycetes (for example, as little as 10 fmol of SGMPII). PMID:1769960

  12. Identification of highly brominated analogues of Q1 in marine mammals.

    PubMed

    Teuten, Emma L; Pedler, Byron E; Hangsterfer, Alexandra N; Reddy, Christopher M

    2006-11-01

    Three novel halogenated organic compounds (HOCs) have been identified in the blubber of marine mammals from coastal New England with the molecular formulae C(9)H(3)N(2)Br(6)Cl, C(9)H(3)N(2)Br(7), and C(9)H(4)N(2)Br(5)Cl. They were identified using high and low resolution gas chromatography mass spectrometry (GCMS) and appear to be highly brominated analogues of Q1, a heptachlorinated HOC suspected to be naturally produced. These compounds were found in Atlantic white sided dolphin (Lagenorhynchus acutus), bottlenose dolphin (Tursiops truncatus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), harbor porpoise (Phocoena phocoena), beluga whale (Delphinapterus leucas), fin whale (Balaenoptera physalus), grey seal (Halichoerus grypus), harp seal (Phoca groenlandica) and a potential food source (Loligo pealei) with concentrations as high as 2.7 microg/g (lipid weight). The regiospecificity of C(9)H(3)N(2)Br(6)Cl is suggestive of a biogenic origin. Debromination of C(9)H(3)N(2)Br(6)Cl may be significant in the formation of C(9)H(4)N(2)Br(5)Cl. PMID:16517037

  13. Static inflation and deflation pressure-volume curves from excised lungs of marine mammals.

    PubMed

    Fahlman, Andreas; Loring, Stephen H; Ferrigno, Massimo; Moore, Colby; Early, Greg; Niemeyer, Misty; Lentell, Betty; Wenzel, Frederic; Joy, Ruth; Moore, Michael J

    2011-11-15

    Excised lungs from eight marine mammal species [harp seal (Pagophilus groenlandicus), harbor seal (Phoca vitulina), gray seal (Halichoerus grypush), Atlantic white-sided dolphin (Lagenorhynchus acutus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), long-finned pilot whale (Globicephala melas) and harbor porpoise (Phocoena phocoena)] were used to determine the minimum air volume of the relaxed lung (MAV, N=15), the elastic properties (pressure-volume curves, N=24) of the respiratory system and the total lung capacity (TLC). Our data indicate that mass-specific TLC (sTLC, l kg(-1)) does not differ between species or groups (odontocete vs phocid) and agree with that estimated (TLC(est)) from body mass (M(b)) by applying the equation: TLC(est)=0.135 M(b)(0.92). Measured MAV was on average 7% of TLC, with a range from 0 to 16%. The pressure-volume curves were similar among species on inflation but diverged during deflation in phocids in comparison with odontocetes. These differences provide a structural basis for observed species differences in the depth at which lungs collapse and gas exchange ceases. PMID:22031747

  14. A preliminary report on the distribution of lizards in Qatar.

    PubMed

    Cogălniceanu, Dan; Castilla, Aurora M; Valdeón, Aitor; Gosá, Alberto; Al-Jaidah, Noora; Alkuwary, Ali; Saifelnasr, Essam O H; Mas-Peinado, Paloma; Richer, Renee; Al-Hemaidi, Ahmad Amer Mohd

    2014-01-01

    We have updated the list of the lizard species present in Qatar and produced the first distribution maps based on two field surveys in 2012 and 2013. We used the QND95/Qatar National Grid with a grid of 10 × 10 km squares for mapping. Our results show the occurrence of 21 lizard species in Qatar, from the 15 species indicated in the last biodiversity report conducted in 2004. The most abundant family found in Qatar is Gekkonidae with nine species (Bunopus tuberculatus, Cyrtopodion scabrum, Hemidactylus robustus, H. flaviviridis, H. persicus, Stenodactylus arabicus, S. slevini, S. doriae, Pseudoceramodactylus khobarensis), followed by Lacertidae with four species (Acanthodactylus schmidti, A. opheodurus, Mesalina brevirostris, M. adramitana), Agamidae with three species (Trapelus flavimaculatus, Uromastyx aegyptia, Phrynocephalus arabicus), Scincidae with two species (Scincus mitranus, Trachylepis septemtaeniata), and Varanidae (Varanus griseus), Sphaerodactylidae (Pristurus rupestris) and Trogonophiidae (Diplometopon zarudnyi) with one species each. The species richness fluctuated largely across Qatar between one and eleven species per grid square. We believe that the lizard fauna records in Qatar are still incomplete and that additional studies are required. However, our study here fills a gap concerning lizard biodiversity knowledge in the Gulf Region. PMID:24493961

  15. Structure of an MmyB-Like Regulator from C. aurantiacus, Member of a New Transcription Factor Family Linked to Antibiotic Metabolism in Actinomycetes

    PubMed Central

    Xu, Qingping; van Wezel, Gilles P.; Chiu, Hsiu-Ju; Jaroszewski, Lukasz; Klock, Heath E.; Knuth, Mark W.; Miller, Mitchell D.; Lesley, Scott A.; Godzik, Adam; Elsliger, Marc-André; Deacon, Ashley M.; Wilson, Ian A.

    2012-01-01

    Actinomycetes are important bacterial sources of antibiotics and other secondary metabolites. Many antibiotic gene clusters are controlled by pathway-specific activators that act in response to growth conditions. Here we present the crystal structure of an MmyB-like transcription regulator MltR (PDB code 3pxp) (Caur_2278) from Chloroflexus aurantiacus, in complex with a fatty acid (myristic acid). MltR is a distant homolog of the methylenomycin activator MmyB and consists of an Xre-type N-terminal DNA-binding domain and a C-terminal ligand-binding module that is related to the Per-Arnt-Sim (PAS) domain. This structure has enabled identification of a new family of bacterial transcription factors that are distributed predominantly in actinomycetes. Bioinformatics analysis of MltR and other characterized family members suggest that they are likely associated with antibiotic and fatty acid metabolism in actinomycetes. Streptomyces coelicolor SCO4944 is a candidate as an ancestral member of the family. Its ortholog in S. griseus, SGR_6891, is induced by A-factor, a γ-butyrolactone that controls antibiotic production and development, and is adjacent to the A-factor synthase gen, afsA. The location of mltR/mmyB homologs, in particular those adjacent to less well-studied antibiotic-related genes, makes them interesting genetic markers for identifying new antibiotic genes. A model for signal-triggered DNA-binding by MltR is proposed. PMID:22844465

  16. Three new gonad-infecting species of Philometra (Nematoda: Philometridae) parasitic in Lutjanus spp. (Lutjanidae) in the northern Gulf of Mexico off Florida, USA.

    PubMed

    Moravec, Frantisek; Bakenhaster, Micah; Fajer-Avila, Emma J

    2014-08-01

    Based on light and scanning electron microscopical studies, three new gonad-infecting species of Philometra Costa, 1845 (Nematoda: Philometridae) are described from marine fishes of the genus Lutjanus Bloch (Perciformes: Lutjanidae) in the northern Gulf of Mexico: P. longispicula sp. n. from the ovary of the northern red snapper L. campechanus (Poey) (type host) and silk snapper L. vivanus (Cuvier); P. latispicula sp. n. from the ovary and rarely testes of the grey snapper L. griseus (Linnaeus); and P. synagridis sp. n. (only males available) from the ovary of the lane snapper Lutjanus synagris (Linnaeus). These species are mainly characterised by the lengths of spicules (378-690 microm, 135-144 microm and 186-219 microm, respectively) and spicule shapes, structure of the distal portion of the gubernaculum and the structure of the male caudal end. These are the first valid, nominal species of gonad-infecting philometrids reported from fishes of the family Lutjanidae in the western Atlantic region. PMID:25185406

  17. Proteolysis in dry fermented sausages: The effect of selected exogenous proteases.

    PubMed

    Díaz, O; Fernandez, M; De Fernando, G D; de la Hoz, L; Ordoñez, J A

    1997-05-01

    The effect of three commercial proteases (pronase E from Streptomyces griseus, aspartyl proteinase from Aspergillus oryzae and papain) on protein breakdown and the sensory characteristics of dry fermented sausages was investigated. Water soluble, non-protein, 5% phosphotungstic acid soluble, 5% sulphosalicylic acid soluble and total volatile basic nitrogen contents increased during fermentation, stabilizing later until the end of ripening (26th day). Nitrogen values were always greater in the aspartyl proteinase added batch in comparison with the other protease added batches. Total free amino acid changes showed a similar pattern to those observed for the 5% sulphosalicylic acid soluble nitrogen. The electrophoretic studies demonstrated that proteolysis of high molecular weight myofibrillar and sarcoplasmic proteins was more prominent in protease added batches. It was especially intensive in papain one. The dominant amino acids at the end of ripening were similar in all batches. Tyramine and histamine increased throughout ripening. No significant differences in sensory properties were found between control and pronase E and papain added batches, but they were significantly different (p < 0.01) from the sausages containing aspartyl proteinase, due to an excessive softening. The effect of exogenous enzyme addition on the flavour potentiation of dry fermented sausage is discussed. PMID:22061850

  18. Preliminary Observations of Population Genetics and Relatedness of the Broadnose Sevengill Shark, Notorynchus cepedianus, in Two Northeast Pacific Estuaries

    PubMed Central

    Larson, Shawn; Farrer, Debbie; Lowry, Dayv; Ebert, David A.

    2015-01-01

    The broadnose sevengill shark, Notorynchus cepedianus, a common coastal species in the eastern North Pacific, was sampled during routine capture and tagging operations conducted from 2005–2012. One hundred and thirty three biopsy samples were taken during these research operations in Willapa Bay, Washington and in San Francisco Bay, California. Genotypic data from seven polymorphic microsatellites (derived from the related sixgill shark, Hexanchus griseus) were used to describe N. cepedianus genetic diversity, population structure and relatedness. Diversity within N. cepedianus was found to be low to moderate with an average observed heterozygosity of 0.41, expected heterozygosity of 0.53, and an average of 5.1 alleles per microsatellite locus. There was no evidence of a recent population bottleneck based on genetic data. Analyses of genetic differences between the two sampled estuaries suggest two distinct populations with some genetic mixing of sharks sampled during 2005–2006. Relatedness within sampled populations was high, with percent relatedness among sharks caught in the same area indicating 42.30% first-order relative relationships (full or half siblings). Estuary-specific familial relationships suggest that management of N. cepedianus on the U.S. West Coast should incorporate stock-specific management goals to conserve this ecologically important predator. PMID:26052706

  19. A preliminary report on the distribution of lizards in Qatar

    PubMed Central

    Cogălniceanu, Dan; Castilla, Aurora M; Valdeón, Aitor; Gosá, Alberto; Al-Jaidah, Noora; Alkuwary, Ali; Saifelnasr, Essam O. H.; Mas-Peinado, Paloma; Richer, Renee; Al-Hemaidi, Ahmad Amer Mohd

    2014-01-01

    Abstract We have updated the list of the lizard species present in Qatar and produced the first distribution maps based on two field surveys in 2012 and 2013. We used the QND95/Qatar National Grid with a grid of 10 × 10 km squares for mapping. Our results show the occurrence of 21 lizard species in Qatar, from the 15 species indicated in the last biodiversity report conducted in 2004. The most abundant family found in Qatar is Gekkonidae with nine species (Bunopus tuberculatus, Cyrtopodion scabrum, Hemidactylus robustus, H. flaviviridis, H. persicus, Stenodactylus arabicus, S. slevini, S. doriae, Pseudoceramodactylus khobarensis), followed by Lacertidae with four species (Acanthodactylus schmidti, A. opheodurus, Mesalina brevirostris, M. adramitana), Agamidae with three species (Trapelus flavimaculatus, Uromastyx aegyptia, Phrynocephalus arabicus), Scincidae with two species (Scincus mitranus, Trachylepis septemtaeniata), and Varanidae (Varanus griseus), Sphaerodactylidae (Pristurus rupestris) and Trogonophiidae (Diplometopon zarudnyi) with one species each. The species richness fluctuated largely across Qatar between one and eleven species per grid square. We believe that the lizard fauna records in Qatar are still incomplete and that additional studies are required. However, our study here fills a gap concerning lizard biodiversity knowledge in the Gulf Region. PMID:24493961

  20. The Rakiura Titi Islands Restoration Project: community action to eradicate Rattus rattus and Rattus exulans for ecological restoration and cultural wellbeing

    USGS Publications Warehouse

    McClelland, P.J; Coote, R.; Trow, M.; Hutchins, P.; Nevins, HannahRose M.; Adams, Josh; Newman, J.; Moller, H.

    2011-01-01

    In 2003, a non-profit group, Ka Mate Nga Kiore, was set up to oversee the restoration of four Maori-owned islands off the south coast of Stewart Island, New Zealand. The first step in the restoration was to eradicate ship rats (Rattus rattus) from three islands and Pacific rats (R. exulans) from another. The eradication was funded by the Command Oil Spill Trustee Council which managed the mitigation money from an oil spill off the Californian coast in 1998. The funding was coordinated via Oikonos Ecosystem Knowledge, a non-profit USA group primarily involved in seabird research and restoration. The project was primarily to benefit sooty shearwater (Puffinus griseus) and to sustain a culturally important customary harvest of their chicks by Rakiura Maori. However, like all island eradications, a wide range of other species also benefited from the removal of rats. The New Zealand Department of Conservation provided technical advice and assistance for the planning and implementation of the eradication programme. This paper describes how, with appropriate funding, community and technical support, rodent eradications can be achieved on private islands. In this case, a range of institutions and individuals joined to achieve a common goal that highlighted a significant international conservation action. We urge that more international and local-community-led restoration projects be initiated in the future.

  1. Isolation and evaluation of proteolytic actinomycete isolates as novel inducers of pearl millet downy mildew disease protection

    PubMed Central

    Jogaiah, Sudisha; Kurjogi, Mahantesh; Govind, Sharathchandra Ramasandra; Huntrike, Shekar Shetty; Basappa, Vedamurthy Ankala; Tran, Lam-Son Phan

    2016-01-01

    Native endophytic actinomycetes isolated from pearl millet roots were examined for their efficacy to protect pearl millet against downy mildew. Nineteen of 39 isolates were found to be proteolytic, of which 7 strains could directly suppress the sporangium formation of Sclerospora graminicola, the pearl millet downy mildew pathogen. Thus, mycelial suspensions containing either spores or cell-free extract of these 7 isolates were used for seed-coating and -soaking treatments to test for their induction of downy mildew resistance. Results indicated that seed-coating overall provided better protection to downy mildew than seed-soaking. In both treatments, the tested isolates demonstrated differential abilities in downy mildew disease protection, with Streptomyces griseus SJ_UOM-07-09 and Streptosporangium roseum SJ_UOM-18-09 showing the highest protection rates. Additionally, the levels of disease protection conferred by the actinomycetes were just slightly lower than that of the systemic fungicide Apron, suggesting their effectiveness. Further studies revealed that the more rapid root colonization by SJ_UOM-18-09 resulted in faster and higher induced resistance in comparison with SJ_UOM-07-09 under greenhouse conditions, indicating that SJ_UOM-18-09 was superior than SJ_UOM-07-09 in inducing resistance. Results from this study provide comprehensive information on biocontrol functions of SJ_UOM- 18-09 with great potential to control downy mildew disease in pearl millet. PMID:27499196

  2. The utility of diversity profiling using Illumina 18S rRNA gene amplicon deep sequencing to detect and discriminate Toxoplasma gondii among the cyst-forming coccidia.

    PubMed

    Cooper, Madalyn K; Phalen, David N; Donahoe, Shannon L; Rose, Karrie; Šlapeta, Jan

    2016-01-30

    Next-generation sequencing (NGS) has the capacity to screen a single DNA sample and detect pathogen DNA from thousands of host DNA sequence reads, making it a versatile and informative tool for investigation of pathogens in diseased animals. The technique is effective and labor saving in the initial identification of pathogens, and will complement conventional diagnostic tests to associate the candidate pathogen with a disease process. In this report, we investigated the utility of the diversity profiling NGS approach using Illumina small subunit ribosomal RNA (18S rRNA) gene amplicon deep sequencing to detect Toxoplasma gondii in previously confirmed cases of toxoplasmosis. We then tested the diagnostic approach with species-specific PCR genotyping, histopathology and immunohistochemistry of toxoplasmosis in a Risso's dolphin (Grampus griseus) to systematically characterise the disease and associate causality. We show that the Euk7A/Euk570R primer set targeting the V1-V3 hypervariable region of the 18S rRNA gene can be used as a species-specific assay for cyst-forming coccidia and discriminate T. gondii. Overall, the approach is cost-effective and improves diagnostic decision support by narrowing the differential diagnosis list with more certainty than was previously possible. Furthermore, it supplements the limitations of cryptic protozoan morphology and surpasses the need for species-specific PCR primer combinations. PMID:26801593

  3. Three Anisakis spp. isolated from toothed whales stranded along the eastern Adriatic Sea coast.

    PubMed

    Blažeković, Kristina; Pleić, Ivana Lepen; Đuras, Martina; Gomerčić, Tomislav; Mladineo, Ivona

    2015-01-01

    Knowledge concerning cetacean ecology in the Mediterranean is limited but important for sustainable planning and enforcement of appropriate conservation measures. Any information that might help to elucidate their ecology is essential. We explored the population and genetic structures of Anisakis spp. nematodes isolated from four toothed whale species - bottlenose dolphins (Tursiops truncatus), striped dolphins (Stenella coeruleoalba), Risso's dolphins (Grampus griseus) and Cuvier's beaked whales (Ziphius cavirostris) - stranded along the eastern Adriatic Sea coast (1990-2012) to reveal more information on host ecological patterns. Lower parasite prevalence was observed in resident dolphin species compared with occasionally occurring species, as well as in young compared with adult dolphins, indicating different feeding habits related to age. No unequivocal relationship between the biological traits of a host (age, body length, body mass and blubber depth) and Anisakis population parameters was observed. Phylogenetic analysis revealed a new geographical record of Anisakis simplex sensu stricto (1.96%) and Anisakis physeteris (1.31%) in the Adriatic Sea in addition to resident Anisakis pegreffii (96.73%). In an assessment of the Adriatic Sea and oceans worldwide, the genetic structure of Anisakis revealed that A. pegreffii populations do not differ among various final host species but do differ with respect to geographical location in contrast to previously accepted Anisakis panmixia. PMID:25449948

  4. Community ecology and disease risk: lizards, squirrels, and the Lyme disease spirochete in California, USA.

    PubMed

    Salkeld, Daniel J; Lane, Robert S

    2010-01-01

    Vector-borne zoonotic diseases are often maintained in complex transmission cycles involving multiple vertebrate hosts and their arthropod vectors. In the state of California, U.S.A., the spirochete Borrelia burgdorferi, which causes Lyme disease, is transmitted between vertebrate hosts by the western black-legged tick, Ixodes pacificus. Several mammalian species serve as reservoir hosts of the spirochete, but levels of tick infestation, reservoir competence, and Borrelia-infection prevalence vary widely among such hosts. Here, we model the host (lizards, Peromyscus mice, Californian meadow voles, dusky-footed wood rats, and western gray squirrels), vector, and pathogen community of oak woodlands in northwestern California to determine the relative importance of different tick hosts. Observed infection prevalence of B. burgdorferi in host-seeking I. pacificus nymphs was 1.8-5.3%, and our host-community model estimated an infection prevalence of 1.6-2.2%. The western gray squirrel (Sciurus griseus) was the only source of infected nymphs. Lizards, which are refractory to Borrelia infection, are important in feeding subadult ticks but reduce disease risk (nymphal infection prevalence). Species identity is therefore critical in understanding and determining the local disease ecology. PMID:20380218

  5. Archivo de placas astrométricas del Observatorio de La Plata

    NASA Astrophysics Data System (ADS)

    di Sisto, R.; Orellana, R. B.

    Se ha realizado una base de datos con las placas fotográficas obtenidas con el Astrográfico del Observatorio de La Plata. Se han clasificado un total de 3000 placas obtenidas para asteroides y cometas. El acceso a la base de datos se hará por FTP y la misma contendrá la siguiente información: fecha y tiempo de exposición, coordenadas del centro de placa, tipo de emulsión fotográfica, estado de la placa, objeto fotografiado.

  6. Facts about Antibiotic Resistance

    MedlinePlus

    ... Trends and Cost Español: Datos breves Facts about Antibiotic Resistance Antibiotic resistance has been called one of the world’s most ... antibiotic use is a key strategy to control antibiotic resistance. Antibiotic resistance in children is of particular concern ...

  7. A Look at Psychometrics in the Netherlands.

    ERIC Educational Resources Information Center

    Hambleton, Ronald K.; Swaminathan, H.

    Comments are made on the review papers presented by six Dutch psychometricians: Ivo Molenaar, Wim van der Linden, Ed Roskam, Arnold Van den Wollenberg, Gideon Mellenbergh, and Dato de Gruijter. Molenaar has embraced a pragmatic viewpoint on Bayesian methods, using both empirical and pure approaches to solve educational research problems. Molenaar…

  8. Homogeneity and Entropy

    NASA Astrophysics Data System (ADS)

    Tignanelli, H. L.; Vazquez, R. A.; Mostaccio, C.; Gordillo, S.; Plastino, A.

    1990-11-01

    RESUMEN. Presentamos una metodologia de analisis de la homogeneidad a partir de la Teoria de la Informaci6n, aplicable a muestras de datos observacionales. ABSTRACT:Standard concepts that underlie Information Theory are employed in order design a methodology that enables one to analyze the homogeneity of a given data sample. Key : DATA ANALYSIS

  9. The Vocational Guidance Research Database: A Scientometric Approach

    ERIC Educational Resources Information Center

    Flores-Buils, Raquel; Gil-Beltran, Jose Manuel; Caballer-Miedes, Antonio; Martinez-Martinez, Miguel Angel

    2012-01-01

    The scientometric study of scientific output through publications in specialized journals cannot be undertaken exclusively with the databases available today. For this reason, the objective of this article is to introduce the "Base de Datos de Investigacion en Orientacion Vocacional" [Vocational Guidance Research Database], based on the use of…

  10. Higher Education and Social Commitment.

    ERIC Educational Resources Information Center

    Nasution, S.; Virasai, Banphot, Eds.

    The proceedings of the Regional Institute of Higher Education and Development's seminar and the meaning and implications of social commitment in higher education are reported. The welcoming address (S. Nasution) and the opening address (Y. B. Dato' Murad bin Mohd. Noor) welcome the participants and set the tone for the discussions to follow. The…

  11. Comunicado de prensa del Informe Anual sobre el Estado del Cáncer 2015

    Cancer.gov

    Por primera vez, los investigadores han usado datos a nivel nacional para determinar la incidencia de los cuatro subtipos moleculares principales de cáncer de seno (mama) por edad, raza y grupo étnico, nivel de pobreza y varios otros factores. El informe

  12. Modeling Treatment Motivation in Substance-Abusing Women with Children

    ERIC Educational Resources Information Center

    Wilke, Dina J.; Kamata, Akihito; Cash, Scottye J.

    2005-01-01

    Objectives: Children are often considered a primary motivator for women seeking substance abuse treatment. This study tested a model predicting treatment motivation in substance-abusing mothers. Methods: This study was a secondary analysis of the Drug Abuse Treatment Outcome Study (DATOS). It used structural equation modeling to describe factors…

  13. Trazando la materia oscura con cúmulos globulares

    NASA Astrophysics Data System (ADS)

    Forte, J. C.

    Se describe la estrategia adoptada para mapear la distribución de materia oscura y bariónica en galaxias elípticas cuyos cúmulos globulares están siendo observados con los telescopios VLT y Gemini. Se ejemplifican los resultados con los datos obtenidos en el cúmulo de Fornax.

  14. Complementos de vitamina E aumentan riesgo de cáncer de próstata

    Cancer.gov

    De acuerdo a una revisión ulterior de los datos del Estudio del Selenio y la Vitamina E para Prevenir el Cáncer (SELECT), los hombres que tomaron diariamente 400 unidades internacionales (U.I.) de vitamina E tuvieron más cánceres de próstata que los hombr

  15. Beneficios y riesgos de la terapia estrogénica en la menopausia varían por edad, de acuerdo con el e

    Cancer.gov

    Los datos de seguimiento a largo plazo del estudio Iniciativa para la Salud de la Mujer (WHI) proporcionan información nueva e importante sobre los posibles riesgos y beneficios de la terapia hormonal para tratar síntomas relacionadas con la menopausia.

  16. Combinación de Valores de Longitud del Día (LOD) según ventanas de frecuencia

    NASA Astrophysics Data System (ADS)

    Fernández, L. I.; Arias, E. F.; Gambis, D.

    El concepto de solución combinada se sustenta en el hecho de que las diferentes series temporales de datos derivadas a partir de distintas técnicas de la Geodesia Espacial son muy disimiles entre si. Las principales diferencias, fácilmente detectables, entre las distintas series son: diferente intervalo de muestreo, extensión temporal y calidad. Los datos cubren un período reciente de 27 meses (julio 96-oct. 98). Se utilizaron estimaciones de la longitud del día (LOD) originadas en 10 centros operativos del IERS (International Earth Rotation Service) a partir de las técnicas GPS (Global Positioning System) y SLR (Satellite Laser Ranging). La serie temporal combinada así obtenida se comparó con la solución EOP (Parámetros de la Orientación Terrestre) combinada multi-técnica derivada por el IERS (C04). El comportamiento del ruido en LOD para todas las técnicas mostró ser dependiente de la frecuencia (Vondrak, 1998). Por esto, las series dato se dividieron en ventanas de frecuencia, luego de haberles removido bies y tendencias. Luego, se asignaron diferentes factores de peso a cada ventana discriminando por técnicas. Finalmente estas soluciones parcialmente combinadas se mezclaron para obtener la solución combinada final. Sabemos que la mejor solución combinada tendrá una precisión menor que la precisión de las series temporales de datos que la originaron. Aun así, la importancia de una serie combinada confiable de EOP, esto es, de una precisión aceptable y libre de sistematismos evidentes, radica en la necesidad de una base de datos EOP de referencia para el estudio de fenómenos geofísicos que motivan variaciones en la rotación terrestre.

  17. Acoustic effects of the ATOC signal (75 Hz, 195 dB) on dolphins and whales

    SciTech Connect

    Au, W.W.; Nachtigall, P.E.; Pawloski, J.L.

    1997-05-01

    The Acoustic Thermometry of Ocean Climate (ATOC) program of Scripps Institution of Oceanography and the Applied Physics Laboratory, University of Washington, will broadcast a low-frequency 75-Hz phase modulated acoustic signal over ocean basins in order to study ocean temperatures on a global scale and examine the effects of global warming. One of the major concerns is the possible effect of the ATOC signal on marine life, especially on dolphins and whales. In order to address this issue, the hearing sensitivity of a false killer whale ({ital Pseudorca crassidens}) and a Risso{close_quote}s dolphin ({ital Grampus griseus}) to the ATOC sound was measured behaviorally. A staircase procedure with the signal levels being changed in 1-dB steps was used to measure the animals{close_quote} threshold to the actual ATOC coded signal. The results indicate that small odontocetes such as the {ital Pseudorca} and {ital Grampus} swimming directly above the ATOC source will not hear the signal unless they dive to a depth of approximately 400 m. A sound propagation analysis suggests that the sound-pressure level at ranges greater than 0.5 km will be less than 130 dB for depths down to about 500 m. Several species of baleen whales produce sounds much greater than 170{endash}180 dB. With the ATOC source on the axis of the deep sound channel (greater than 800 m), the ATOC signal will probably have minimal physical and physiological effects on cetaceans. {copyright} {ital 1997 Acoustical Society of America.}

  18. Transmission cycles of Borrelia burgdorferi and B. bissettii in relation to habitat type in northwestern California.

    PubMed

    Eisen, Lars; Eisen, Rebecca J; Mun, Jeomhee; Salkeld, Daniel J; Lane, Robert S

    2009-06-01

    This study was undertaken to determine which rodent species serve as primary reservoirs for the Lyme disease spirochete Borrelia burgdorferi in commonly occurring woodland types in inland areas of northwestern California, and to examine whether chaparral or grassland serve as source habitats for dispersal of B. burgdorferi- or B. bissettii-infected rodents into adjacent woodlands. The western gray squirrel (Sciurus griseus) was commonly infected with B. burgdorferi in oak woodlands, whereas examination of 30 dusky-footed woodrats (Neotoma fuscipes) and 280 Peromyscus spp. mice from 13 widely spaced Mendocino County woodlands during 2002 and 2003 yielded only one infected woodrat and one infected deer mouse (P. maniculatus). These data suggest that western gray squirrels account for the majority of production by rodents of fed Ixodes pacificus larvae infected with B. burgdorferi in the woodlands sampled. Infections with B. burgdorferi also were rare in woodrats (0/47, 0/3) and mice (3/66, 1/6) captured in chaparral and grassland, respectively, and therefore these habitats are unlikely sources for dispersal of this spirochete into adjacent woodlands. On the other hand, B. bissettii was commonly detected in both woodrats (22/47) and mice (15/66) in chaparral. We conclude that the data from this and previous studies in northwestern California are suggestive of a pattern where inland oak-woodland habitats harbor a B. burgdorferi transmission cycle driven primarily by I. pacificus and western gray squirrels, whereas chaparral habitats contain a B. bissettii transmission cycle perpetuated largely by I. spinipalpis, woodrats and Peromyscus mice. The dominant role of western gray squirrels as reservoirs of B. burgdorferi in certain woodlands offers intriguing opportunities for preventing Lyme disease by targeting these animals by means of either host-targeted acaricides or oral vaccination against B. burgdorferi. PMID:20514140

  19. Comparative anatomy of the foramen ovale in the hearts of cetaceans.

    PubMed

    Macdonald, Alastair A; Carr, Peter A; Currie, Richard J W

    2007-07-01

    The structure of the cardiac foramen ovale from 17 species representing six cetacean families, the Monodontidae, Phocoenidae, Delphinidae, Ziphiidae, Balaenidae and the Balaenopteridae, was studied using the scanning electron microscope. Eight white whale fetuses (Delphinapterus leucas) and a narwhal fetus (Monodon monoceros) represented the Monodontidae; one fetal and nine neonatal harbour porpoises (Phocoena phocoena) and a finless porpoise fetus (Neophocoena phocoenoides) represented the Phocoenidae; two white-beaked dolphin fetuses (Lagenorhynchus albirostris), four fetal and one neonatal Atlantic white-sided dolphins (Lagenorhynchus acutus), a Risso's dolphin fetus (Grampus griseus), two common bottle-nosed dolphin neonates (Tursiops truncatus), a female short-beaked common dolphin fetus (Delphinus delphis), four killer whale fetuses (Orcinus orca) and two long-finned pilot whale fetuses (Globicephala melas) represented the Delphinidae; two northern bottlenose whale fetuses (Hyperoodon ampullatus) represented the Ziphiidae; one bowhead whale fetus (Balaena mysticetus) represented the Balaenidae and five Common minke whale fetuses (Balaenoptera acutorostrata), one blue whale fetus (Balaenoptera musculus), nine fin whale fetuses (Balaenoptera physalus) and four humpback whale fetuses (Megaptera novaeangliae) represented the Balaenopteridae. The hearts of an additional two incompletely identified toothed and four baleen whale fetuses were also studied. In each species the fold of tissue derived from the cardiac septum primum and subtended by the foramen ovale had the appearance of a short tunnel or sleeve which was fenestrated at its distal end. In the toothed whales the tissue fold was tunnel-shaped with the interatrial septum as the floor whereas in baleen whales it was more sleeve-like. In toothed whales thin threads extended from the fold to insert into the interatrial septum whereas a network of threads covered the distal end of the sleeve in the baleen

  20. Ordination of breeding birds in relation to environmental gradients in three southeastern United States floodplain forests

    USGS Publications Warehouse

    Wakeley, J.S.; Guilfoyle, M.P.; Antrobus, T.J.; Fischer, R.A.; Barrow, W.C., Jr.; Hamel, P.B.

    2007-01-01

    We used an ordination approach to identify factors important to the organization of breeding bird communities in three floodplains: Cache River, Arkansas (AR), Iatt Creek, Louisiana (LA), and the Coosawhatchie River, South Carolina (SC), USA. We used 5-min point counts to sample birds in each study area each spring from 1995 to 1998, and measured ground-surface elevations and a suite of other habitat variables to investigate bird distributions and community characteristics in relation to important environmental gradients. In both AR and SC, the average number of Neotropical migrant species detected was lowest in semipermanently flooded Nyssa aquatica Linnaeus habitats and greatest in the highest elevation floodplain zone. Melanerpes carolinus Linnaeus, Protonotaria citrea Boddaert, Quiscalus quiscula Linnaeus, and other species were more abundant in N. aquatica habitats, whereas Wilsonia citrina Boddaert, Oporornis formosus Wilson, Vireo griseus Boddaert, and others were more abundant in drier floodplain zones. In LA, there were no significant differences in community metrics or bird species abundances among forest types. Canonical correspondence analyses revealed that structural development of understory vegetation was the most important factor affecting bird distributions in all three study areas; however, potential causes of these structural gradients differed. In AR and SC, differences in habitat structure were related to the hydrologic gradient, as indexed by ground-surface elevation. In LA, structural variations were related mainly to the frequency of canopy gaps. Thus, bird communities in all three areas appeared to be organized primarily in response to repeated localized disturbance. Our results suggest that regular disturbance due to flooding plays an important role in structuring breeding bird communities in floodplains subject to prolonged inundation, whereas other agents of disturbance (e.g., canopy gaps) may be more important in headwater systems

  1. Nutrient digestibility and evaluation of protein and carbohydrate fractionation of citrus by-products.

    PubMed

    Lashkari, S; Taghizadeh, A

    2013-08-01

    The protein and carbohydrate fractionation and nutrient digestibility of citrus by-products were determined. Ruminal, intestinal and total tract CP disappearance values were measured by a modified three-step (MTSP) method and in vitro CP disappearance method (IVCP). Test feeds were orange pulp (OP), lime pulp (LP), lemon pulp (LEP), grapefruit pulp (GP), sweet lemon pulp (SLP), bitter lemon pulp (BLP), bergamot orange pulp (BP) and tangerine pulp (TP). The rumen undegradable protein (RUP) fractions of the feedstuffs were obtained by ruminal incubation in three cannulated wethers and incubation in protease solution (protease type xiv, Streptomyces griseus). The data were analysed using completely randomized design. There were significant differences between the tested feeds in protein fractions and acid detergent insoluble nitrogen (ADIN; C fraction) was highest in GP (14.56%) (p<0.001). For carbohydrate fraction, the highest C fraction was also observed in GP (2.67%) and in relation to the other citrus pulps (p<0.001). Ruminal CP disappearance was highest in OP (71.89%) (p<0.001). The level of post-ruminal CP disappearance, measured by MTSP, was highest for BP (34.94%) (p<0.001). The highest in vitro dry matter digestibility (IVDMD) was found for TP (80.44%) followed by that estimated for BP (78.38%) (p<0.001). The estimated metabolizable energy (MJ/kg DM) varied from 9.77 for LP to 12.91 for BP. Tangerine pulp had the highest true rumen digestibility (TRD) (p<0.001). According to the results, it could be concluded that citrus by-products have high nutritive value and also, the in vitro techniques can be easily used to determine of the nutritive value of citrus by-products. PMID:22703299

  2. Does growth rate determine the rate of metabolism in shorebird chicks living in the Arctic?

    PubMed

    Williams, Joseph B; Tieleman, B Irene; Visser, G Henk; Ricklefs, Robert E

    2007-01-01

    We measured resting and peak metabolic rates (RMR and PMR, respectively) during development of chicks of seven species of shorebirds: least sandpiper (Calidris minutilla; adult mass 20-22 g), dunlin (Calidris alpina; 56-62 g), lesser yellowlegs (Tringa flavipes; 88-92 g), short-billed dowitcher (Limnodromus griseus; 85-112 g), lesser golden plover (Pluvialis dominicana; 150-156 g), Hudsonian godwit (Limosa haemastica; 205-274 g), and whimbrel (Numenius phaeopus; 380 g). We tested two opposing hypotheses: the growth rate-maturity hypothesis, which posits that growth rate in chicks is inversely related to functional maturity of tissues, and the fast growth rate-high metabolism hypothesis, which suggests that rapid growth is possible only with a concomitant increase in either RMR or PMR. We have found no evidence that chicks of shorebirds with fast growth rates have lower RMRs or lower PMRs, as would be predicted by the growth rate-maturity hypothesis, but our data suggested that faster-growing chest muscles resulted in increased thermogenic capacity, consistent with the fast growth-high metabolism hypothesis. The development of homeothermy in smaller species is a consequence primarily of greater metabolic intensities of heat-generating tissues. The maximum temperature gradient between a chick's body and environment that can be maintained in the absence of a net radiative load increased rapidly with body mass during development and was highest in least sandpipers and lowest among godwits. Chicks of smaller species could maintain a greater temperature gradient at a particular body mass because of their higher mass-specific maximum metabolic rates. PMID:17717813

  3. Diurnal and nocturnal visual capabilities in shorebirds as a function of their feeding strategies.

    PubMed

    Rojas, L M; McNeil, R; Cabana, T; Lachapelle, P

    1999-01-01

    Some shorebird species forage with the same feeding strategy at night and during daytime, e.g. visual pecking in the Wilson's Plover (Charadrius wilsonia) or tactile probing in the Short-billed Dowitcher (Limnodromus griseus). The American Woodcock (Scolopax minor) uses tactile probing, by day and by night, but sometimes pecks for insects during daytime. The Black-winged Stilt (Himantopus himantopus) is a visual pecker, both by day and by night, and sometimes forages tactilely on windy (agitated water surface) moonless nights. Territorial Willets (Catoptrophorus semipalmatus) are visual peckers during daylight and on moonlight conditions but switch to tactile feeding under lower light conditions. It could be postulated that some shorebird species would switch from visual feeding during daytime to tactile foraging at night because they have poor night vision compared to species that are always sight foragers irrespective of the time of the day. This issue was examined by comparing retinal structure and function in the above species. Electroretinograms (ERGs) were obtained at different light intensities from anesthetized birds, and the retinae were processed for histological observations. Based on ERGs, retinal sensitivity, and rod:cone ratios, both plovers and stilts are well adapted for nocturnal vision. Although they have low rod density compared to that of stilts and plovers, Willets and woodcocks have a scotopic retinal sensitivity similar to that of stilts and plovers but rank midway between plovers and dowitchers for the b-wave amplitude. Dowitchers have the lowest scotopic b-wave amplitude and retinal sensitivity and appear the least well adapted for night vision. Based on photopic ERGs and cone densities, although stilts, Willets and dowitchers appear as well adapted for daytime vision, plovers occupy the last rank of all species examined. Compared to the nighttime tactile feeders and those that switch from daytime visual pecking to tactile feeding at night

  4. Diversity and Distribution Patterns of Cetaceans in the Subtropical Southwestern Atlantic Outer Continental Shelf and Slope.

    PubMed

    Di Tullio, Juliana Couto; Gandra, Tiago B R; Zerbini, Alexandre N; Secchi, Eduardo R

    2016-01-01

    Temporal and spatial patterns of cetacean diversity and distribution were investigated through eight ship-based surveys carried out during spring and autumn between 2009 and 2014 on the outer continental shelf (~150m) and slope (1500m) off southeastern and southern Brazil (~23°S to ~34°S). The survey area was divided into southeast and south areas according to their oceanographic characteristics. Twenty-one species were observed in 503 sightings. The overall number of species was similar between the two areas, though it was higher in the spring in the south area. Five species were dominant and diversity varied more seasonally than spatially. ANOVA and kernel analyses showed that overall cetacean densities were higher in spring compared to autumn. Physeter macrocephalus, the most frequent species, concentrated throughout the south area at depths over 1000m in both seasons. Despite the overlapped occurrence at a broader scale, small delphinids presented latitudinal and in-offshore gradients as well as seasonal variation in distribution patterns, which could indicate habitat partitioning between some species. Delphinus delphis was only recorded in the south and its density decreased in areas where the presence of Stenella frontalis increased, mainly beyond the 250m isobath. Densities of S. longirostris and S. attenuata increased in lower latitudes and beyond the shelf break. The large delphinids Tursiops truncatus and Globicephala melas formed mixed groups in many occasions and were observed along the study area around depths of 500m. Grampus griseus was twice as frequent in the south area and densities increased in waters deeper than 600m. As expected, densities of both small and large migratory whales were higher during spring, over the continental slope, in the southeast area. The results presented here provided strong evidence on the importance of the outer continental shelf and slope to a diverse community of cetaceans occurring in the subtropical Southwestern

  5. Spring-time distributions of migratory marine birds in the southern California Current: Oceanic eddy associations and coastal habitat hotspots over 17 years

    NASA Astrophysics Data System (ADS)

    Yen, P. P. W.; Sydeman, W. J.; Bograd, S. J.; Hyrenbach, K. D.

    2006-02-01

    We used a 17-year time series of shipboard observations to address the hypothesis that marine birds associate with persistent hydrographic features in the southern California Current System (CCS). Overall, approximately 27,000 km of ocean habitat were surveyed, averaging 1600 km per cruise. We identified mesoscale features (eddy centers and the core of the California Current), based on dynamic height anomalies, and considered habitat associations for seven migratory seabird species: black-footed albatross ( Phoebastria nigripes), Cook's petrel ( Pterodroma cookii), Leach's storm-petrel ( Oceanodroma leucorhoa), dark shearwaters (mainly sooty shearwater Puffinus griseus, with a few short-tailed shearwaters Puffinus tenuirostris), northern fulmar ( Fulmarus glacialis), red phalarope ( Phalaropus fulicaria), and red-necked phalarope ( Phalaropus lobatus). We explored associations (presence/absence and density relationships) of marine birds with mesoscale features (eddies, current jet) and metrics of primary productivity (chlorophyll a and nitrate concentrations). Mesoscale eddies were consistently identified in the study region, but were spatially and temporally variable. The resolved eddies were large-scale features associated with meanders of the equatorward-flowing California Current. Cook's petrel was found offshore with no specific habitat affinities. Black-footed albatross, red phalarope, and Leach's storm petrel were found in association with offshore eddies and/or the core of the California Current, but the functional relationship for these species varied, possibly reflecting differences in flight capabilities. The more coastal species, including the shearwaters, fulmar, and red-necked phalarope, were positively associated with proxies of primary productivity. Of the hydrographic habitats considered, the upwelling region of Point Conception appears to be an important "hotspot" of sustained primary production and marine bird concentrations. Point Conception and

  6. First description of deep-water elasmobranch assemblages in the Exuma Sound, The Bahamas

    NASA Astrophysics Data System (ADS)

    Brooks, Edward J.; Brooks, Annabelle M. L.; Williams, Sean; Jordan, Lance K. B.; Abercrombie, Debra; Chapman, Demian D.; Howey-Jordan, Lucy A.; Grubbs, R. Dean

    2015-05-01

    Deep-sea chondrichthyans, like many deep-water fishes, are very poorly understood at the most fundamental biological, ecological and taxonomic levels. Our study represents the first ecological investigation of deep-water elasmobranch assemblages in The Bahamas, and the first assessment of species-specific resilience to capture for all of the species captured. Standardised deep-water longline surveys (n=69) were conducted September to December 2010 and 2011 between 472 m and 1024 m deep, resulting in the capture of 144 sharks from 8 different species. These included the Cuban dogfish, Squalus cubensis, the bigeye sixgill shark, Hexanchus nakamurai, the bluntnose sixgill shark, Hexanchus griseus, the smooth dogfish, Mustelus canis insularis, the roughskin dogfish, Centroscymnus owstoni, Springer's sawtail catshark, Galeus springeri and the false catshark, Pseudotriakis microdon. Preliminary genetic analysis indicated two or more species of gulper sharks, Centrophorus spp.; however, for the present study they were treated as a single species complex. Water depth and distance from the rocky structure of the Exuma Sound wall were inversely correlated with species richness, whereas seabed temperature was directly correlated with species richness. These variables also had a significant influence on the abundance and distribution of many species. Expanded depth ranges were established for S. cubensis and H. nakamurai, which, in the case of S. cubensis, is thought to be driven by thermal preferences. At-vessel mortality rates increased significantly with depth, and post-release mortality was thought to be high for some species, in part due to high post-release predation. This study highlights the importance of utilising strategic geographic locations that provide easy access to deep water, in combination with traditional expedition-based deep-ocean science, to accelerate the acquisition of fundamental ecological and biological insights into deep-sea elasmobranchs.

  7. The use of non destructive biomarkers in the study of marine mammals.

    PubMed

    M Cristina Fossi And Letizia Marsili

    1997-01-01

    Marine mammals have been subject to heavy anthropogenic pressure by direct killing and chemical pollution all over the world. Most studies of contamination and biomarker responses in marine mammals have been conducted using animals killed by hunting out of a total of 12 cetacean species studied, 45 of the specimens were obtained by sacrificing the animal; out of a total of eight pinniped species studied, 40 of the specimens were obtained by killing. The development of a series of non destructive techniques to evaluate biomarker responses and residue levels is recommended for the hazard assessment and conservation of endangered species of marine mammals. Here we review the current status of the non destructive biomarker approach in marine mammals, describing the biological materials available for non destructive tests in stranded brain, liver, blood, skin, subcutaneous blubber, muscle and fur and free ranging animals blood, skin biopsy, fur and faeces and the respective biomarker techniques mixed function oxidase activity and DNA damage in skin biopsy samples; porphyrins in faeces and fur; esterases, porphyrins, clinical biochemical parameter, vitamin A and micronuclei in blood samples. Residue analysis can be carried out in the various biological materials. We also report the results of applying this methodological approach to cetaceans minke whale Balaenoptera acutorostrata, fin whale-- Balaenoptera physalus, beluga whale-- Delphinapterus leucas, short finned pilot whale-- Globicephala macrorhynchus, harbour porpoise -- Phocoena phocoena, Rissos dolphin-- Risso s Grampus griseus, Dall s porpoise-- Phocoenoides dalli dalli, melon headed whale-- Peponocephala electra, bottlenose dolphin -- Tursiops truncatus, striped dolphin-- Stenella coeruleoalba, spinner dolphin-- Stenella longirostris, killer whale-- Orcinus orca and pinnipeds northern fur seal- Callorhinus ursinus, hooded seal-- Cystophora cristata, grey seal-- Halichoerus grypus, harbour seal-- Phoca vitulina

  8. Transmission cycles of Borrelia burgdorferi and B. bissettii in relation to habitat type in northwestern California

    PubMed Central

    Eisen, Lars; Eisen, Rebecca J.; Mun, Jeomhee; Salkeld, Daniel J.; Lane, Robert S.

    2008-01-01

    This study was undertaken to determine which rodent species serve as primary reservoirs for the Lyme disease spirochete Borrelia burgdorferi in commonly occurring woodland types in inland areas of northwestern California, and to examine whether chaparral or grassland serve as source habitats for dispersal of B. burgdorferi- or B. bissettii-infected rodents into adjacent woodlands. The western gray squirrel (Sciurus griseus) was commonly infected with B. burgdorferi in oak woodlands, whereas examination of 30 dusky-footed woodrats (Neotoma fuscipes) and 280 Peromyscus spp. mice from 13 widely spaced Mendocino County woodlands during 2002 and 2003 yielded only one infected woodrat and one infected deer mouse (P. maniculatus). These data suggest that western gray squirrels account for the majority of production by rodents of fed Ixodes pacificus larvae infected with B. burgdorferi in the woodlands sampled. Infections with B. burgdorferi also were rare in woodrats (0/47, 0/3) and mice (3/66, 1/6) captured in chaparral and grassland, respectively, and therefore these habitats are unlikely sources for dispersal of this spirochete into adjacent woodlands. On the other hand, B. bissettii was commonly detected in both woodrats (22/47) and mice (15/66) in chaparral. We conclude that the data from this and previous studies in northwestern California are suggestive of a pattern where inland oak-woodland habitats harbor a B. burgdorferi transmission cycle driven primarily by I. pacificus and western gray squirrels, whereas chaparral habitats contain a B. bissettii transmission cycle perpetuated largely by I. spinipalpis, woodrats and Peromyscus mice. The dominant role of western gray squirrels as reservoirs of B. burgdorferi in certain woodlands offers intriguing opportunities for preventing Lyme disease by targeting these animals by means of either host-targeted acaricides or oral vaccination against B. burgdorferi. PMID:20514140

  9. Cleavage of peptide bonds bearing ionizable amino acids at P{sub 1} by serine proteases with hydrophobic S{sub 1} pocket

    SciTech Connect

    Qasim, Mohammad A.; Song, Jikui; Markley, John L.; Laskowski, Michael

    2010-10-01

    Research highlights: {yields} Large pK shifts in ionizable groups when buried in the protein interior. {yields} Substrate dependent shifts in pH optimum for serine proteases. {yields} Lys side chain is a stronger acid in serine protease S{sub 1} pocket than Asp side chain. -- Abstract: Enzymatic hydrolysis of the synthetic substrate succinyl-Ala-Ala-Pro-Xxx-pNA (where Xxx = Leu, Asp or Lys) catalyzed by bovine chymotrypsin (CHYM) or Streptomyces griseus protease B (SGPB) has been studied at different pH values in the pH range 3-11. The pH optima for substrates having Leu, Asp, and Lys have been found to be 7.5-8.0, 5.5-6.0, and {approx}10, respectively. At the normally reported pH optimum (pH 7-8) of CHYM and SGPB, the substrate with Leu at the reactive site is more than 25,000-fold more reactive than that with Asp. However, when fully protonated, Asp is nearly as good a substrate as Leu. The pK values of the side chains of Asp and Lys in the hydrophobic S{sub 1} pocket of CHYM and SGPB have been calculated from pH-dependent hydrolysis data and have been found to be about 9 for Asp and 7.4 and 9.7 for Lys for CHYM and SGPB, respectively. The results presented in this communication suggest a possible application of CHYM like enzymes in cleaving peptide bonds contributed by acidic amino acids between pH 5 and 6.

  10. ET743: Chemical analysis of the sea squirt Ecteinascidia turbinata ecosystem.

    PubMed

    Manning, Thomas; Rhodes, Emily; Loftis, Richard; Phillips, Dennis; Demaria, Don; Newman, David; Rudloe, Jack

    2006-05-10

    The sea squirt Ecteinascidia turbinata produces the powerful drug ET743. In this study Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) and Matrix Assisted Laser Desorption Ionization-Mass Spectrometry (MALDI-MS) are systematically used to measure elemental and molecular species in a Florida Keys mangrove ecosystem that contains the sea squirt. ICP-AES is used to measure the concentration of 27 elements down to the parts per billion level in 16 organisms and 3 sediment samples that reside in the mangrove ecosystem including turtle grass, blue crabs, fire sponge, and lettuce slugs. MALDI-MS is used to search for ET743 in these same organisms and sediment samples. A mass spectral feature corresponding to ET743 is identified in the extract of the sea squirt, red mangrove root (Rhizophera mangle), the schoolmaster snapper (Lutjanus griseus), and a sediment sample taken from the ecosystem. We use MALDI-MS to study the impact that various environmental conditions, such as UV light, I(2), cation binding (Fe(+3), Zn(+2), Pb(+2), Cu(+2)), metal oxide nanoparticles (FeO, CuO, TiO(2), ZnO, Al(2)O(3)), a common mineral (CaCO(3)), and extremes in acidity (0.1 M HCl, 0.1 M NaOH) have on the ET743 structure. The data provide potential structures (degradation products, metal-ligand complexes, etc.) that might be present in organism or sedimentary extracts that are similar to ET743. We are studying the marine geochemistry of this ecosystem so a broth can be developed and tested for producing this marine natural product. PMID:16644544

  11. Interaction of proteases with legume seed inhibitors. Molecular features.

    PubMed

    de Seidl, D S

    1996-12-01

    Streptomyces griseus, but do not interact with either animal digestive or plant thiol enzymes. PMID:9137634

  12. New records of stink bugs (Hemiptera: Pentatomidae) from Colombia.

    PubMed

    Castro-Huertas, Valentina; Schwertner, Cristiano F; Fernández, Fernando

    2015-01-01

    New records of genera and species of stink bugs (Hemiptera: Pentatomidae) from Colombia are provided. Two genera are new records for South America: Alathetus and Schraderiellus. Fifteen genera are new record for Colombia: Agaclitus, Boea, Ceratozygum, Euthyrhynchus, Eritrachys, Doesburguedessa, Lopadusa, Marmessulus, Paralincus, Patanius, Peromatus, Phalaecus, Phoeacia, Rio, and Tyrannocoris. Forty-nine species from five subfamiles are recorded for the first time in Colombia. Asopinae: Coryzorhaphis carneolus Erichson, Coryzorhaphis superba Breddin, Euthyrhynchus floridanus (Linnaeus), Podisus sagitta Fabricius, Stiretrus anchorago (Fabricius), Stiretrus cinctellus Germar, Tylospilus peruvianus Horvath, Tyrannocoris nigriceps Thomas. Cyrtocorinae: Ceratozygum horridum (Germar). Discocephalinae: Agaclitus dromedarius Stål, Antiteuchus melanoleucus (Westwood), Antiteuchus sepulcralis (Fabricius), Dinocoris gibbosus (Fallou), Dinocoris variolosus (Linnaeus), Discocephalessa terminalis (Walker), Dryptocephala crenata Ruckes, Dryptocephala dentifrons (Latreille), Eurystethus ovalis Ruckes, Paralcippus dimidiatus (Ruckes), Alathetus rufitarsus Dallas, Eritrachys bituberculata Ruckes, Paralincus bimaculatus (Ruckes), Schraderiellus cinctus (Ruckes), Xynocoris recavus (Garbelotto & Campos). Edessinae: Brachystethus cribus (Fabricius), Brachystethus tricolor Bolívar, Doesburguedessa elongatispina Fernandes and Lopadusa fuscopunctata (Distant). Pentatominae: Banasa fulgida Thomas, Banasa paraexpallescens Thomas, Dichelops divisus (Walker), Dichelops nigrum Bergroth, Euschistus carbonerus Rolston, Mormidea bovilla (Distant), Mormidea triangularis (Walker), Murgantia bifasciata Herrich-Schaeffer, Murgantia violascens (Westwood), Oebalus pugnax (Fabricius), Oebalus ypsilon-griseus (DeGeer), Odmalea concolor (Walker), Patanius vittatus Rolston, Proxys albopunctulatus (Palisot), Proxys punctulatus (Palisot), Rhyncholepta grandicallosa Bergroth, Rio insularis Ruckes, Roferta

  13. Diversity and Distribution Patterns of Cetaceans in the Subtropical Southwestern Atlantic Outer Continental Shelf and Slope

    PubMed Central

    Di Tullio, Juliana Couto; Gandra, Tiago B. R.; Zerbini, Alexandre N.; Secchi, Eduardo R.

    2016-01-01

    Temporal and spatial patterns of cetacean diversity and distribution were investigated through eight ship-based surveys carried out during spring and autumn between 2009 and 2014 on the outer continental shelf (~150m) and slope (1500m) off southeastern and southern Brazil (~23°S to ~34°S). The survey area was divided into southeast and south areas according to their oceanographic characteristics. Twenty-one species were observed in 503 sightings. The overall number of species was similar between the two areas, though it was higher in the spring in the south area. Five species were dominant and diversity varied more seasonally than spatially. ANOVA and kernel analyses showed that overall cetacean densities were higher in spring compared to autumn. Physeter macrocephalus, the most frequent species, concentrated throughout the south area at depths over 1000m in both seasons. Despite the overlapped occurrence at a broader scale, small delphinids presented latitudinal and in-offshore gradients as well as seasonal variation in distribution patterns, which could indicate habitat partitioning between some species. Delphinus delphis was only recorded in the south and its density decreased in areas where the presence of Stenella frontalis increased, mainly beyond the 250m isobath. Densities of S. longirostris and S. attenuata increased in lower latitudes and beyond the shelf break. The large delphinids Tursiops truncatus and Globicephala melas formed mixed groups in many occasions and were observed along the study area around depths of 500m. Grampus griseus was twice as frequent in the south area and densities increased in waters deeper than 600m. As expected, densities of both small and large migratory whales were higher during spring, over the continental slope, in the southeast area. The results presented here provided strong evidence on the importance of the outer continental shelf and slope to a diverse community of cetaceans occurring in the subtropical Southwestern

  14. Seasonal and Ontogenetic Changes in Movement Patterns of Sixgill Sharks

    PubMed Central

    Andrews, Kelly S.; Williams, Greg D.; Levin, Phillip S.

    2010-01-01

    Background Understanding movement patterns is fundamental to population and conservation biology. The way an animal moves through its environment influences the dynamics of local populations and will determine how susceptible it is to natural or anthropogenic perturbations. It is of particular interest to understand the patterns of movement for species which are susceptible to human activities (e.g. fishing), or that exert a large influence on community structure, such as sharks. Methodology/Principal Findings We monitored the patterns of movement of 34 sixgill sharks Hexanchus griseus using two large-scale acoustic arrays inside and outside Puget Sound, Washington, USA. Sixgill sharks were residents in Puget Sound for up to at least four years before making large movements out of the estuary. Within Puget Sound, sixgills inhabited sites for several weeks at a time and returned to the same sites annually. Across four years, sixgills had consistent seasonal movements in which they moved to the north from winter to spring and moved to the south from summer to fall. Just prior to leaving Puget Sound, sixgills altered their behavior and moved twice as fast among sites. Nineteen of the thirty-four sixgills were detected leaving Puget Sound for the outer coast. Three of these sharks returned to Puget Sound. Conclusions/Significance For most large marine predators, we have a limited understanding of how they move through their environment, and this clouds our ability to successfully manage their populations and their communities. With detailed movement information, such as that being uncovered with acoustic monitoring, we can begin to quantify the spatial and temporal impacts of large predators within the framework of their ecosystems. PMID:20838617

  15. Bacterial versus fungal laccase: potential for micropollutant degradation

    PubMed Central

    2013-01-01

    Relatively high concentrations of micropollutants in municipal wastewater treatment plant (WWTP) effluents underscore the necessity to develop additional treatment steps prior to discharge of treated wastewater. Microorganisms that produce unspecific oxidative enzymes such as laccases are a potential means to improve biodegradation of these compounds. Four strains of the bacterial genus Streptomyces (S. cyaneus, S. ipomoea, S. griseus and S. psammoticus) and the white-rot fungus Trametes versicolor were studied for their ability to produce active extracellular laccase in biologically treated wastewater with different carbon sources. Among the Streptomyces strains evaluated, only S. cyaneus produced extracellular laccase with sufficient activity to envisage its potential use in WWTPs. Laccase activity produced by T. versicolor was more than 20 times greater, the highest activity being observed with ash branches as the sole carbon source. The laccase preparation of S. cyaneus (abbreviated LSc) and commercial laccase from T. versicolor (LTv) were further compared in terms of their activity at different pH and temperatures, their stability, their substrate range, and their micropollutant oxidation efficiency. LSc and LTv showed highest activities under acidic conditions (around pH 3 to 5), but LTv was active over wider pH and temperature ranges than LSc, especially at near-neutral pH and between 10 and 25°C (typical conditions found in WWTPs). LTv was also less affected by pH inactivation. Both laccase preparations oxidized the three micropollutants tested, bisphenol A, diclofenac and mefenamic acid, with faster degradation kinetics observed for LTv. Overall, T. versicolor appeared to be the better candidate to remove micropollutants from wastewater in a dedicated post-treatment step. PMID:24152339

  16. Bacterial versus fungal laccase: potential for micropollutant degradation.

    PubMed

    Margot, Jonas; Bennati-Granier, Chloé; Maillard, Julien; Blánquez, Paqui; Barry, David A; Holliger, Christof

    2013-01-01

    Relatively high concentrations of micropollutants in municipal wastewater treatment plant (WWTP) effluents underscore the necessity to develop additional treatment steps prior to discharge of treated wastewater. Microorganisms that produce unspecific oxidative enzymes such as laccases are a potential means to improve biodegradation of these compounds. Four strains of the bacterial genus Streptomyces (S. cyaneus, S. ipomoea, S. griseus and S. psammoticus) and the white-rot fungus Trametes versicolor were studied for their ability to produce active extracellular laccase in biologically treated wastewater with different carbon sources. Among the Streptomyces strains evaluated, only S. cyaneus produced extracellular laccase with sufficient activity to envisage its potential use in WWTPs. Laccase activity produced by T. versicolor was more than 20 times greater, the highest activity being observed with ash branches as the sole carbon source. The laccase preparation of S. cyaneus (abbreviated LSc) and commercial laccase from T. versicolor (LTv) were further compared in terms of their activity at different pH and temperatures, their stability, their substrate range, and their micropollutant oxidation efficiency. LSc and LTv showed highest activities under acidic conditions (around pH 3 to 5), but LTv was active over wider pH and temperature ranges than LSc, especially at near-neutral pH and between 10 and 25°C (typical conditions found in WWTPs). LTv was also less affected by pH inactivation. Both laccase preparations oxidized the three micropollutants tested, bisphenol A, diclofenac and mefenamic acid, with faster degradation kinetics observed for LTv. Overall, T. versicolor appeared to be the better candidate to remove micropollutants from wastewater in a dedicated post-treatment step. PMID:24152339

  17. Comparative anatomy of the foramen ovale in the hearts of cetaceans

    PubMed Central

    Macdonald, Alastair A; Carr, Peter A; Currie, Richard J W

    2007-01-01

    The structure of the cardiac foramen ovale from 17 species representing six cetacean families, the Monodontidae, Phocoenidae, Delphinidae, Ziphiidae, Balaenidae and the Balaenopteridae, was studied using the scanning electron microscope. Eight white whale fetuses (Delphinapterus leucas) and a narwhal fetus (Monodon monoceros) represented the Monodontidae; one fetal and nine neonatal harbour porpoises (Phocoena phocoena) and a finless porpoise fetus (Neophocoena phocoenoides) represented the Phocoenidae; two white-beaked dolphin fetuses (Lagenorhynchus albirostris), four fetal and one neonatal Atlantic white-sided dolphins (Lagenorhynchus acutus), a Risso's dolphin fetus (Grampus griseus), two common bottle-nosed dolphin neonates (Tursiops truncatus), a female short-beaked common dolphin fetus (Delphinus delphis), four killer whale fetuses (Orcinus orca) and two long-finned pilot whale fetuses (Globicephala melas) represented the Delphinidae; two northern bottlenose whale fetuses (Hyperoodon ampullatus) represented the Ziphiidae; one bowhead whale fetus (Balaena mysticetus) represented the Balaenidae and five Common minke whale fetuses (Balaenoptera acutorostrata), one blue whale fetus (Balaenoptera musculus), nine fin whale fetuses (Balaenoptera physalus) and four humpback whale fetuses (Megaptera novaeangliae) represented the Balaenopteridae. The hearts of an additional two incompletely identified toothed and four baleen whale fetuses were also studied. In each species the fold of tissue derived from the cardiac septum primum and subtended by the foramen ovale had the appearance of a short tunnel or sleeve which was fenestrated at its distal end. In the toothed whales the tissue fold was tunnel-shaped with the interatrial septum as the floor whereas in baleen whales it was more sleeve-like. In toothed whales thin threads extended from the fold to insert into the interatrial septum whereas a network of threads covered the distal end of the sleeve in the baleen

  18. Mitogenomic phylogenetic analyses of the Delphinidae with an emphasis on the Globicephalinae

    PubMed Central

    2011-01-01

    Background Previous DNA-based phylogenetic studies of the Delphinidae family suggest it has undergone rapid diversification, as characterised by unresolved and poorly supported taxonomic relationships (polytomies) for some of the species within this group. Using an increased amount of sequence data we test between alternative hypotheses of soft polytomies caused by rapid speciation, slow evolutionary rate and/or insufficient sequence data, and hard polytomies caused by simultaneous speciation within this family. Combining the mitogenome sequences of five new and 12 previously published species within the Delphinidae, we used Bayesian and maximum-likelihood methods to estimate the phylogeny from partitioned and unpartitioned mitogenome sequences. Further ad hoc tests were then conducted to estimate the support for alternative topologies. Results We found high support for all the relationships within our reconstructed phylogenies, and topologies were consistent between the Bayesian and maximum-likelihood trees inferred from partitioned and unpartitioned data. Resolved relationships included the placement of the killer whale (Orcinus orca) as sister taxon to the rest of the Globicephalinae subfamily, placement of the Risso's dolphin (Grampus griseus) within the Globicephalinae subfamily, removal of the white-beaked dolphin (Lagenorhynchus albirostris) from the Delphininae subfamily and the placement of the rough-toothed dolphin (Steno bredanensis) as sister taxon to the rest of the Delphininae subfamily rather than within the Globicephalinae subfamily. The additional testing of alternative topologies allowed us to reject all other putative relationships, with the exception that we were unable to reject the hypothesis that the relationship between L. albirostris and the Globicephalinae and Delphininae subfamilies was polytomic. Conclusion Despite their rapid diversification, the increased sequence data yielded by mitogenomes enables the resolution of a strongly

  19. Responses of algae, corals and fish to the reduction of macroalgae in fished and unfished patch reefs of Glovers Reef Atoll, Belize

    NASA Astrophysics Data System (ADS)

    McClanahan, T.; McField, M.; Huitric, M.; Bergman, K.; Sala, E.; Nyström, M.; Nordemar, I.; Elfwing, T.; Muthiga, N.

    2001-05-01

    Macroalgae were experimentally reduced by approximately 2.5 kg/m2 on eight similar-sized patch reefs of Glovers Reef Atoll, Belize, in September 1998. Four of these reefs were in a protected "no-take" zone and four were in a "general use" fishing zone. Eight adjacent reefs (four in each management zone) were also studied as unmanipulated controls to determine the interactive effect of algal reduction and fisheries management on algae, coral, fish, and rates of herbivory. The 16 reefs were sampled five times for 1 year after the manipulation. We found that the no-fishing zone had greater population densities for 13 of 30 species of fish, including four herbivorous species, but lower herbivory levels by sea urchins. However, there was lower stony coral cover and higher macroalgal cover in the "no-take" zone, both prior to and after the experiment. There were no significant effects of management on the percent cover of fleshy macroalgae. The algal reduction resulted in an increase in six fish species, including four herbivores and two which feed on invertebrates. One species, Lutjanus griseus, declined in experimental reefs. Macroalgal biomass quickly recovered from the reduction in both management areas within a few months, and by species-level community measures within 1 year, while stony coral was reduced in all treatments. Coral bleaching and Hurricane Mitch disturbed the site at the beginning of the study period and may explain the loss of stony coral and rapid increase in erect algae. We suggest that reducing macroalgae, as a technique to restore turf and encrusting coralline algae and stony corals, may work best after reefs have been fully protected from fishing for a period long enough to allow herbivorous fish to recover (i.e. >5 years). Further ecological studies on Glovers Reef are required to understand the shift from coral to algal dominance that has occurred on this reef in the last 25 years.

  20. Enhanced Detection of Post-Transcriptional Modifications Using a Mass-Exclusion List Strategy for RNA Modification Mapping by LC-MS/MS

    PubMed Central

    2015-01-01

    There has been a renewed appreciation for the dynamic nature of ribonucleic acid (RNA) modifications and for the impact of modified RNAs on organism health resulting in an increased emphasis on developing analytical methods capable of detecting modifications within specific RNA sequence contexts. Here we demonstrate that a DNA-based exclusion list enhances data dependent liquid chromatography tandem mass spectrometry (LC-MS/MS) detection of post-transcriptionally modified nucleosides within specific RNA sequences. This approach is possible because all post-transcriptional modifications of RNA, except pseudouridine, result in a mass increase in the canonical nucleoside undergoing chemical modification. Thus, DNA-based sequences reflect the state of the RNA prior to or in the absence of modification. The utility of this exclusion list strategy is demonstrated through the RNA modification mapping of total tRNAs from the bacteria Escherichia coli, Lactococcus lactis, and Streptomyces griseus. Creation of a DNA-based exclusion list is shown to consistently enhance the number of detected modified ribonuclease (RNase) digestion products by ∼20%. All modified RNase digestion products that were detected during standard data dependent acquisition (DDA) LC-MS/MS were also detected when the DNA-based exclusion list was used. Consequently, the increase in detected modified RNase digestion products is attributed to new experimental information only obtained when using the exclusion list. This exclusion list strategy should be broadly applicable to any class of RNA and improves the utility of mass spectrometry approaches for discovery-based analyses of RNA modifications, such as are required for studies of the epitranscriptome. PMID:26176336

  1. Microbial toxin's effect on mitochondrial survival by increasing K+ uptake.

    PubMed

    Saris, N-E Leo; Andersson, Maria A; Mikkola, Raimo; Andersson, Leif C; Teplova, Vera V; Grigoriev, Pavel A; Salkinoja-Salonen, Mirja S

    2009-08-01

    We studied the effects of toxins, which inhibited the motility of boar spermatozoa, on rat liver mitochondria. The toxins studied were originally from bacteria isolated from moisture-damaged buildings where inhabitants exhibited symptoms, or from food causing poisoning. Some strains of Bacillus cereus and Streptomyces griseus produced potassium ionophoric peptides cereulide and valinomycin (Mikkola, et al., European Journal of Biochemistry 1999; 263: 112-117). Of interest is that channels were formed in black-lipid membranes (BLM) with a selectivity of K(+) > Na(+) at a concentration of 26 nM. Recently, bafilomycin A1--an inhibitor of V-H(+)ATPases--was found also to be a K(+)-specific ionophore active at nanomolar concentrations (Teplova, et al., J Bioenerg Biomembr 2007; 39: 321-329), while B. amyloliquefaciens produced amylosin, a cation channel-forming peptide with a higher selectivity for K(+) over Na(+) at around 200 nM concentrations (Mikkola, et al., Toxicon 2007; 49: 1158-1171). Of interest is that channels were formed in BLM with a selectivity of K(+) > Na(+) at a concentration of 26 nM. The ionophores and the channel-forming amylosin caused swelling of energized mitochondria due to uptake of K(+), loss of membrane potential, inhibition of maximal respiration rates due to loss of pyridine nucleotides, and inhibition of ATP synthesis. Various cell types may have different sensitivities to the effects of the ionophores. Thus, the mitochondrial membrane potential in neuronal cells was more sensitive to cereulide than in differentiated Paju cells (Teplova, et al., Acta Biochimica Polonica 2004; 51: 539-544). Swelling causes release of proapoptotic factors from mitochondria, which explains that undifferentiated neuronal cells were sensitive, while differentiated Paju cells were resistant, which probably is due to them having an increased expression of the antiapoptotic protein Bcl-2 and the neuroprotective stanniocalcin. PMID:19736254

  2. Nesting success of birds in different silvicultural treatments in southeastern U.S. Pine Forests

    USGS Publications Warehouse

    Barber, D.R.; Martin, T.E.; Melchiors, M.A.; Thill, R.E.; Wigley, T.B.

    2001-01-01

    We examined nesting success and levels of nest predation and cowbird parasitism among five different silvicultural treatments: regenerating (3-6 years old), mid-rotation (12-15 years old), and thinned (17-23 years old) pine plantations, single-tree selection, and late-rotation pine-hardwood stands in the Ouachita Mountains of Arkansas from 1993 to 1995. We monitored 1674 nests. Differences in daily mortality and daily predation rate among two or more treatments were found for 4 and 3 of 12 species, respectively. These differences were lost following Bonferroni adjustments, but thinned stands had higher levels of predation than single-tree selection stands when predation levels were averaged across species. Daily predation rates were positively correlated with the relative abundance of birds, suggesting that nest predators respond to prey availability (i.e., nests) in a density-dependent manner. The relative abundance of cowbirds differed among treatments, with the highest densities in regenerating, thinned, and single-tree selection stands. Field Sparrows (Spizella pusilla) and Yellow-breasted Chats (Icteria virens) experienced higher levels of parasitism in thinned than regenerating plantations, whereas White-eyed Vireos (Vireo griseus) experienced higher parasitism in regenerating plantations than in mid-rotation or thinned plantations. Several shrub-nesting and 1 ground-nesting species had lower nesting success in thinned and regenerating plantations than has been reported in previously published studies. Thus, some seral stages of even-aged management may provide low-quality nesting habitat for several early-successional bird species. In contrast, many species nesting in mid-rotation and single-tree selection stands had nesting success similar to or greater than that found in previous studies, suggesting that some silvicultural treatments, when embedded in a largely forested landscape, may provide suitable habitat for forest land birds without affecting their

  3. Differential exposure to Anaplasma phagocytophilum in rodent species in northern California.

    PubMed

    Foley, Janet E; Clueit, S Bernadette; Brown, Richard N

    2008-01-01

    Anaplasma phagocytophilum is a zoonotic tick-borne rickettsial pathogen that causes granulocytic anaplasmosis (GA) in humans, horses, and dogs. In California, dusky-footed woodrats (Neotoma fuscipes) are a putative reservoir host, and Ixodes pacificus is a vector for transmission from rodents to humans, dogs, and horses. Cases are clustered in coastal and Sierra Nevada foothill regions, but not necessarily in proximity to infected woodrats. This study was designed to compare exposures and active infections of A. phagocytophilum in multiple rodents at a fine spatial scale in a hyperenzootic area and to evaluate the spatial clustering of infections. Of 331 rodents, the seroprevalence was 14.5%, with 60% in tree squirrels (Sciurus griseus and Tamiasciurus douglasii), 29% in woodrats, 14% in flying squirrels (Glaucomys sabrinus), and 5% in chipmunks (Tamias senex). No seropositive ground squirrels (Spermophilus beecheyi) were detected. The seroprevalence was significantly higher west of the Trinity River (23.1%) than east (11.8%) of the river. One Douglas squirrel and one western gray squirrel were polymerase chain reaction (PCR) positive. There was more spatial clustering among seropositive animals compared with all animals tested across the spatial scales evaluated, and this clustering was significantly greater than expected by chance alone. A significant cluster of 24 seropositive animals was found west of the Trinity River, with a population of 56 animals considered within the 50% population-at-risk, and a radius of 362.8 meters. The diversity of cricetine and sciurid rodents infected suggests that squirrels and chipmunks may be underappreciated contributors to A. phagocytophilum ecology in the western United States. The spatial clustering of exposed animals suggests interesting underlying spatially heterogeneous environmental variables that could facilitate the persistence of A. phagocytophilum in nature. PMID:18047398

  4. A Column Experiment To Determine Black Shale Degradation And Colonization By Means of δ13C and 14C Analysis Of Phospholipid Fatty Acids And DNA Extraction

    NASA Astrophysics Data System (ADS)

    Seifert, A.; Gleixner, G.

    2008-12-01

    We investigated the degradation of black shale organic matter by microbial communities. We inoculated two columns respectively, with the fungi Schizophyllum commune, the gram-positive bacterium Pseudomonas putida and the gram-negative bacteria Streptomyces griseus and Streptomyces chartreusis. These microorganisms are known to degrade a wide variety of organic macromolecules. Additionally, we had two sets of control columns. To one set the same nutrient solution was added as to the inoculated columns and to the other set only sterile deionised water was supplied. All columns contained 1.5 kg of freshly crushed not autoclaved black shale material with a particle size of 0.63-2 mm. The columns were incubated at 28° C and 60% humidity in the dark. The aim was to investigate, which microorganisms live on black shales and if these microorganisms are able to degrade ancient organic matter. We used compound specific stable isotope measurement techniques and compound specific 14C-dating methods. After 183 days PLFAs were extracted from the columns to investigate the microbial community, furthermore we extracted on one hand total-DNA of column material and on the other hand DNA from pure cultures isolates which grew on Kinks-agar B, Starch-casein-nitrate-agar (SCN) and on complete-yeast-medium-agar (CYM). According to the PLFA analysis bacteria dominated in the columns, whereas in pure cultures more fungi were isolated. A principal component analysis revealed differences between the columns in accordance with the inoculation, but it seems that the inoculated microorganisms were replaced by the natural population. For AMS measurements palmitic acid (C 16:0) was re-isolated from total-PLFA-extract with a preparative fraction collector (PFC). Preliminary results of the study revealed that microorganisms are able to degrade black shale material and that PLFA analysis are useful methods to be combined with analysis of stable isotope and 14C measurements to study microbial

  5. The Influence of Topographic and Dynamic Cyclic Variables on the Distribution of Small Cetaceans in a Shallow Coastal System

    PubMed Central

    de Boer, Marijke N.; Simmonds, Mark P.; Reijnders, Peter J. H.; Aarts, Geert

    2014-01-01

    The influence of topographic and temporal variables on cetacean distribution at a fine-scale is still poorly understood. To study the spatial and temporal distribution of harbour porpoise Phocoena phocoena and the poorly known Risso’s dolphin Grampus griseus we carried out land-based observations from Bardsey Island (Wales, UK) in summer (2001–2007). Using Kernel analysis and Generalized Additive Models it was shown that porpoises and Risso’s appeared to be linked to topographic and dynamic cyclic variables with both species using different core areas (dolphins to the West and porpoises to the East off Bardsey). Depth, slope and aspect and a low variation in current speed (for Risso’s) were important in explaining the patchy distributions for both species. The prime temporal conditions in these shallow coastal systems were related to the tidal cycle (Low Water Slack and the flood phase), lunar cycle (a few days following the neap tidal phase), diel cycle (afternoons) and seasonal cycle (peaking in August) but differed between species on a temporary but predictable basis. The measure of tidal stratification was shown to be important. Coastal waters generally show a stronger stratification particularly during neap tides upon which the phytoplankton biomass at the surface rises reaching its maximum about 2–3 days after neap tide. It appeared that porpoises occurred in those areas where stratification is maximised and Risso’s preferred more mixed waters. This fine-scale study provided a temporal insight into spatial distribution of two species that single studies conducted over broader scales (tens or hundreds of kilometers) do not achieve. Understanding which topographic and cyclic variables drive the patchy distribution of porpoises and Risso’s in a Headland/Island system may form the initial basis for identifying potentially critical habitats for these species. PMID:24466031

  6. Histological, immunohistochemical and pathological features of the pituitary gland of odontocete cetaceans from the Western gulf of Mexico.

    PubMed

    Cowan, D F; Haubold, E M; Tajima, Y

    2008-01-01

    Pituitary glands were recovered from dolphins and small whales found stranded along the Texas coast of the Gulf of Mexico over a 15-year period (1991-2006). One hundred animals of 14 species were found to be suitable for inclusion in this study. Of these, 72 were Atlantic bottlenose dolphins (Tursiops truncatus). Other species included were the melon-headed whale (Peponocephala electra), spinner dolphin (Stenella longirostris), striped dolphin (Stenella coeruleoalba), pantropical spotted dolphin (Stenella attenuata), pygmy sperm whale (Kogia breviceps), dwarf sperm whale (Kogia sima), Risso's dolphin (Grampus griseus), the short finned pilot whale (Globicephala macrorhyncha), false killer whale (Pseudorca crassidens), Fraser's dolphin (Lagenorhynchus hosei), rough-tooth dolphin (Steno bredanensis), Gervais's beaked whale (Mesoplodon europaeus) and an infant sperm whale (Physeter catodon). The pituitary weights in T. truncatus ranged from 0.69 g in a 109-cm long neonate to 3.44 g in a large (277 cm) male. More typical weights were in the range of 0.95-2.35 g (mean=1.65+/-0.70 g) The cetacean pituitary consisted of two distinct parts, the adenohypophysis and the neurohypophysis, which were separated by a thin fibrous membrane in all species examined, in contrast to terrestrial mammals in which the parts are apposed and joined through a pars intermedia. Cell types were identified with conventional stains and immunohistochemistry. Cells positive for adrenocorticotropic hormone, follicle stimulating hormone, growth hormone, melanocyte stimulating hormone, luteinizing hormone and prolactin were identified with appropriate antibodies. Lesions, which were few, included one pituicytoma of the pars nervosa and a squamous cyst in T. truncatus, and colloid cysts in several species. Nodular aggregates of single cell types were common, probably representing a physiological variant. PMID:18621384

  7. Predictive model for epoxide hydrolase-generated stereochemistry in the biosynthesis of nine-membered enediyne antitumor antibiotics.

    PubMed

    Horsman, Geoffrey P; Lechner, Anna; Ohnishi, Yasuo; Moore, Bradley S; Shen, Ben

    2013-08-01

    Nine-membered enediyne antitumor antibiotics C-1027, neocarzinostatin (NCS), and kedarcidin (KED) possess enediyne cores to which activity-modulating peripheral moieties are attached via (R)- or (S)-vicinal diols. We have previously shown that this stereochemical difference arises from hydrolysis of epoxide precursors by epoxide hydrolases (EHs) with different regioselectivities. The inverting EHs, such as SgcF, hydrolyze an (S)-epoxide substrate to yield an (R)-diol in C-1027 biosynthesis, whereas the retaining EHs, such as NcsF2 and KedF, hydrolyze an (S)-epoxide substrate to yield an (S)-diol in NCS and KED biosynthesis. We now report the characterization of a series of EH mutants and provide a predictive model for EH regioselectivity in the biosynthesis of the nine-membered enediyne antitumor antibiotics. A W236Y mutation in SgcF increased the retaining activity toward (S)-styrene oxide by 3-fold, and a W236Y/Q237M double mutation in SgcF, mimicking NcsF2 and KedF, resulted in a 20-fold increase in the retaining activity. To test the predictive utility of these mutations, two putative enediyne biosynthesis-associated EHs were identified by genome mining and confirmed as inverting enzymes, SpoF from Salinospora tropica CNB-440 and SgrF (SGR_625) from Streptomyces griseus IFO 13350. Finally, phylogenetic analysis of EHs revealed a familial classification according to inverting versus retaining activity. Taken together, these results provide a predictive model for vicinal diol stereochemistry in enediyne biosynthesis and set the stage for further elucidating the origins of EH regioselectivity. PMID:23844627

  8. A predictive model for epoxide hydrolase-generated stereochemistry in the biosynthesis of 9-membered enediyne antitumor antibiotics

    PubMed Central

    Horsman, Geoffrey P.; Lechner, Anna; Ohnishi, Yasuo; Moore, Bradley S.; Shen, Ben

    2013-01-01

    Nine-membered enediyne antitumor antibiotics C-1027, neocarzinostatin (NCS), and kedarcidin (KED) possess enediyne cores to which activity-modulating peripheral moieties are attached via (R)- or (S)-vicinal diols. We have previously shown that this stereochemical difference arises from hydrolysis of epoxide precursors by epoxide hydrolases (EHs) with different regioselectivities – the “inverting” EH, such as SgcF, hydrolyzes an (S)-epoxide substrate to yield an (R)-diol in C-1027 biosynthesis, while the “retaining” EHs, such as NcsF2 and KedF, hydrolyze an (S)-epoxide substrate to yield an (S)-diol in NCS and KED biosynthesis. We now report the characterization of a series of EH mutants and provide a predictive model for EH regioselectivity in the biosynthesis of the 9-membered enediyne antitumor antibiotics. A W236Y mutation in SgcF increased the retaining activity towards (S)-styrene oxide 3-fold, and a W236Y/Q237M double mutation in SgcF, mimicking NcsF2 and KedF, resulted in a 20-fold increase in the retaining activity. To test the predictive utility of these mutations, two putative enediyne biosynthesis-associated EHs were identified by genome mining and confirmed as inverting enzymes – SpoF from Salinospora tropica CNB-440 and SgrF (SGR_625) from Streptomyces griseus IFO 13350. Finally, phylogenetic analysis of EHs revealed a familial classification according to inverting versus retaining activity. Taken together, these results provide a predictive model for the vicinal diol stereochemistry in enediyne biosynthesis and set the stage for further elucidating the origins of EH regioselectivity. PMID:23844627

  9. Species Delimitation in Taxonomically Difficult Fungi: The Case of Hymenogaster

    PubMed Central

    Stielow, Benjamin; Bratek, Zoltan; Orczán, Akos Kund I.; Rudnoy, Szabolcs; Hensel, Gunnar; Hoffmann, Peter; Klenk, Hans-Peter; Göker, Markus

    2011-01-01

    Background False truffles are ecologically important as mycorrhizal partners of trees and evolutionarily highly interesting as the result of a shift from epigeous mushroom-like to underground fruiting bodies. Since its first description by Vittadini in 1831, inappropriate species concepts in the highly diverse false truffle genus Hymenogaster has led to continued confusion, caused by a large variety of prevailing taxonomical opinions. Methodology In this study, we reconsidered the species delimitations in Hymenogaster based on a comprehensive collection of Central European taxa comprising more than 140 fruiting bodies from 20 years of field work. The ITS rDNA sequence dataset was subjected to phylogenetic analysis as well as clustering optimization using OPTSIL software. Conclusions Among distinct species concepts from the literature used to create reference partitions for clustering optimization, the broadest concept resulted in the highest agreement with the ITS data. Our results indicate a highly variable morphology of H. citrinus and H. griseus, most likely linked to environmental influences on the phenology (maturity, habitat, soil type and growing season). In particular, taxa described in the 19th century frequently appear as conspecific. Conversely, H. niveus appears as species complex comprising seven cryptic species with almost identical macro- and micromorphology. H. intermedius and H. huthii are described as novel species, each of which with a distinct morphology intermediate between two species complexes. A revised taxonomy for one of the most taxonomically difficult genera of Basidiomycetes is proposed, including an updated identification key. The (semi-)automated selection among species concepts used here is of importance for the revision of taxonomically problematic organism groups in general. PMID:21311589

  10. [Proteolytic enzymes from Streptomyces fradiae: a metalloendopeptidase, subtilisin-like, and trypsin-like proteinases].

    PubMed

    Bormatova, M E; Ivanova, N M; Iusupova, M P; Voiushina, T L; Surova, I A; Chestukhina, G G; Stepanov, V M

    1996-02-01

    Three proteolytic enzymes-the metalloproteinase, SFMP, and two serine proteinases, SFSP and SFTP-have been isolated and purified from the culture fluid of Streptomyces fradiae using chromatography on bacitracin-silochrome, bacitracin-Sepharose, DEAE-cellulose and fractionation by ammonium sulfate. Study of physico-chemical and functional properties of the enzymes and structural analysis revealed that SFMP is a cysteine-containing metalloendopeptidase with M(r) of 36 kDa, has a peak activity for synthetic substrates at pH 7.0-7.5 and at 60-65 degrees C and is stable at pH 7.0-9.0. The serine proteinase SFSP is related to subtilisin-like enzymes, has a M(r) of 29 kDa and a pH optimum at 7.5-8.5 at temperature up to 50 degrees C. The proteinase is stable at pH 4.0-9.0 and retains 30% of its activity at 70 degrees C. The other serine proteinase, SFTP, has a M(r) of 26 kDa and is related to trypsin-like enzymes. Its activity for synthetic substrates of trypsin is maximal at pH 6.8-8.8 at 50 degrees C. The enzyme is stable at pH 4.5-8.5 and at temperature below 50 degrees C. It has been shown that Streptomyces fradiae, like Streptomyces griseus and other Streptomycetes, possesses an ability to secrete serine proteinases (SFSP and SFTP) related to two evolutionally distinct families of serine proteinases, i.e., subtilisin and chymotrypsin families. SFMP and SFSP have been isolated and characterized for the first time. PMID:8717499

  11. A continuous spectrophotometric assay for Pseudomonas aeruginosa LasA protease (staphylolysin) using a two-stage enzymatic reaction.

    PubMed

    Kessler, Efrat; Safrin, Mary; Blumberg, Shmaryahu; Ohman, Dennis E

    2004-05-15

    Pseudomonas aeruginosa LasA protease is a secreted metalloendopeptidase that can lyse Staphylococcus aureus cells by cleaving the pentaglycine bridges of their peptidoglycan. It can also degrade elastin and stimulate shedding of cell-surface proteoglycans, activities implicated in pathogenesis of P. aeruginosa infections. The activity of LasA protease can be assayed spectrophotometrically by following the reduction in turbidity of S. aureus cell suspensions. This assay, however, does not permit kinetic studies and its reproducibility is poor. Here we describe a two-stage enzymatic reaction for the continuous measurement of LasA protease activity using a defined substrate, succinyl-Gly-Gly-Phe-4-nitroanilide, supplemented with Streptomyces griseus aminopeptidase. Cleavage of the Gly-Phe bond by LasA protease is followed by hydrolysis of the product Phe-4-nitroanilide by the aminopeptidase and the rate of release of the chromophore (4-nitroaniline) is measured spectrophotometrically using a 96-well microplate reader. Activity of nanogram amounts of LasA protease could be determined within a few minutes. Furthermore, this assay permitted the determination of Km and kcat values for LasA protease, which were 0.46 mM and 11.8s(-1), respectively. Pseudomonas elastase was also active in the assay. However, it was less effective than LasA protease and its activity was inhibited by phosphoramidon. The assay is highly sensitive and reproducible, providing a convenient tool for further studies of LasA protease function(s) and mechanism of action. PMID:15113701

  12. Trypsin-kallikrein isoinhibitor K (type Kunitz) from snails (Helix pomatia). Purification and characterization.

    PubMed

    Dietl, T; Tschesche, H

    1975-10-15

    A basic proteinase inhibitor, isoinhibitor K, was purified by SE-Sephadex C-25 column chromatography from the mixture of acid-stable and heat-stable isoinhibitors of the snail (Helix pomatia). Isoinhibitor K is homogeneous in polyacrylamide gel, cellulose acetate and polyacrylamide-dodecylsulfate electrophoresis. From the electrophoretic mobility in dodecylsulfate-polyacrylamide gel and apparent molecular weight of 6500 +/- 200 was estimated. From the amino acid composition the inhibitor consists of 58 amino acid residues. It contains three disulfide bridges, a C-terminal valine and a lysine residue at the reactive site. Isoinhibitor K inhibits the enzymes: bovine trypsin and chymotrypsin, porcine plasmin and pancreatic kallikrein, the trypsin-like component of Streptomyces griseus proteinase-pronase E, and fungi proteinase K from Tritirachium album Limber, which is only inhibited very slightly in contrast to the effect of the mixture of isoinhibitors. The inhibitory effect of isoinhibitor K against these enzymes is compared to that of the mixture or of other isoinhibitors. The following enzymes are not inhibited by isoinhibitor K: Aspergillus proteinase P and alkaline bacillus proteinase 2231 (Röhm), which both are inhibited by the mixture of isoinhibitors. Porcine elastase, bacterial proteinase N (M) (Röhm), and a trypsin-like proteinase from wheat are not inhibited, porcine acrosin and porcine serum kallikrein only to a very minor extent by the mixture of isoinhibitors. Reactive-site peptide-bond cleavage during inhibition could not be detected. Thus, the inhibitory behaviour is just as broad in specificity and as unusual as that of the trypsin-kallikrein inhibitor (Kunitz) from bovine organs. The N-terminus is blocked by pyroglutamic acid. Isoinhibitor K is the main component of the isoinhibitors secreted into the mucus and amounts to 35-40% of the mixture. PMID:1081050

  13. The role of the white-eyed vireo in the dispersal of bersera fruit on the Yucatan Peninsula

    USGS Publications Warehouse

    Greenberg, R.; Foster, M.S.; Marquez-Valdelamar, L.

    1995-01-01

    White-eyed vireos (Vireo griseus) winter in the forests and secondary growth of the Yucatan Peninsula where Bursera simaruba (Burseraceae) is an abundant tree Twenty-five per cent of all white-eyed vireos observed foraging visited Bursera trees In addition, presence and abundance of territorial white-eyed vireos in small forest patches were correlated with the size of the Bursera crop Vireos were the most reliable dispersers of Bursera seeds These birds visited 32 of 35 trees observed for at least three hours. They accounted for approximately half of all bird visits, and two-thirds of the seeds dispersed. Most of the other species rarely visited (<5% of visits) or failed to remove seeds from the tree. Peculiarities of phenology and fruit structure may contribute to the tendency of Bursera to be dispersed by relatively few species The capsules of Bursera fruits do not open when the fruit ripens; birds apparently locate ripe fruit using visual cues, although these are few In addition, only a small portion of the crop ripens daily over a 7- or 8-month period. The vireo-Bursera simaruba relationship, found regionally on the Yucatan Peninsula, may result from the prolonged fruit ripening period (October-March), the relatively depauperate frugivore community and the relatively high density of small Bursera trees in the hurricane-disturbed dry forests. Small trees at all times, and all trees from October to February, depend upon territorial vireos for continuous, highly efficient local dispersal of a small number of fruits In March and April residual fruits ripen rapidly and synchronously, attracting a greater variety of visitors for broad spectrum dispersal during a period of food scarcity. Thus, Bursera has an unusual two-phase phenological pattern, perhaps alternately to take advantage of both specialized and opportunistic dispersers.

  14. Mercury bioaccumulation and trophic transfer in sympatric snapper species from the Gulf of Mexico.

    PubMed

    Bank, Michael S; Chesney, Edward; Shine, James P; Maage, Amund; Senn, David B

    2007-10-01

    Consumption of marine fish is a major route of toxic methyl mercury (MeHg) exposure to ocean apex predators and human populations. Here we explore the influence of trophic structure on total mercury (Hg) accumulation in red snapper (RS, Lutjanus campechanus) and gray snapper (GS, Lutjanus griseus) from the coastal Louisiana region of the Gulf of Mexico, west of the Mississippi River. The objectives of this investigation were to: (1) determine the effectiveness of the use of offshore recreational fishing charter boats and marinas as sources of fish samples and (2) compare species differences in Hg bioaccumulation, trophic position, and carbon sources. Our data show that length-normalized Hg concentrations (> or = 97% as MeHg in tissue of both species) were 230% greater in GS in comparison to RS collected from the same general area. Stable C and N isotope signatures (delta15N and delta13C) indicate that GS occupy a slightly higher trophic position (approximately 30% of one trophic position higher) on the Gulf food web in comparison to RS and that GS appear to incorporate higher trophic positioned prey, continually and at smaller sizes. Mercury was strongly correlated with combined delta15N and delta13C in pooled species data, arguing that most of the substantial difference in Hg bioaccumulation between RS and GS can be explained by modest differences in their trophic position and, to a lesser degree, carbon sources, which had low variation and high overlap among species. These observations demonstrate that even minor to moderate differences in trophic position and food habits in sympatric species can create relatively large differences in bioaccumulation regimes and underscores the importance of quantitative characterization of trophic structure in marine MeHg bioaccumulation studies. PMID:17974344

  15. Mapa Geologico de Venezuela a Escala 1:750,000

    USGS Publications Warehouse

    Hackley, Paul C.; Urbani, Franco; Karlsen, Alex W.; Garrity, Christopher P.

    2006-01-01

    Se presenta un mapa geologico digital de Venezuela sobre un fondo de relieve sombreado. Los datos geologicos e hidrologicos del norte del rio Orinoco proceden de la digitalizacion de mapas geologicos en papel a escala 1:500.000. Estos datos fueron integrados con el mapa geologico digital del Escudo de Guayana Venezolano, a su vez derivado de hojas en papel a escala 1:500.000. La informacion sobre los tipos de fallas mostrados en el mapa es igual que en las fuentes originales. Los poligonos geologicos fueron atribuidos por edad, litologia y nombre de la unidad siguiendo el Codigo geologico de Venezuela. Se incorporaron revisiones significativas de la geologia de la Cordillera de la Costa a partir de las nuevas hojas integradas a escala 1:25.000. Toda esta informacion geologico-estructural se sobrepuso a una imagen de relieve sombreado, producida por el procesamiento de los datos de radar interferometrico con 90 m (3 arcosegundos) de resolucion espacial obtenidos por la mision topografica de radar del transbordador espacial (SRTM). Las areas de la base de datos del SRTM carentes de informacion fueron llenadas por medio de la interpolacion de los datos de las celdas adyacentes. Para producir la imagen de relieve sombreado se uso una direccion de iluminacion de 315 deg con un angulo de 65 deg sobre el horizonte. La proyeccion usada en el mapa es conica equidistante, con latitudes de 4 y 9 deg norte como paralelos estandar y una longitud de 66 deg al oeste como meridiano central. Los datos en el mapa proceden primordialment de hojas a escala 1:500.000 y el producto esta preparado para una impresion optima en escala 1:750.000. Los usuarios pueden obtener ampliaciones mayores, sin embargo no se garantiza la precision del mapa a escalas mas detalladas. Especialmente en la region de Guayana, al sobreponer los mapas geologicos sobre la reciente imagen SRTM, se notan grandes discrepancias no sistematicas tanto en contactos como en fallas. Esto es debido a que los mapas

  16. Physical and Chemical Processes Opacity Project: an Overview and Some Preliminary Results

    NASA Astrophysics Data System (ADS)

    Mendoza, C.

    1990-11-01

    RESUMEN. El Proyecto de la Opacidad es un esfuerzo internacional dedicado a calcular con precisi6n la gran cantidad de datos at6micos que se necesitan para estimar opacidades en los envolventes estelares. Describimos el panorama general del proyecto incluyendo aspectos astrofisicos, flsico-at6micos y computacionales. El volumen y calidad de los datos que se estan generando se puede apreciar en los resultados preliminares que se presentan. ABSTRACT The Opacity Project is an international effort dedicated to the calculation of the vast, accurate, atomic data required to estimate stellar envelope opacities. We give an overview of the project including astrophysical, atomic-physical and computational aspects. The volume and quality of the data which are being generated can be appreciated in the preliminary results that are presented. }% words: ATOMIC PROCESSES - OPACITIES - STARS-INThRIORS

  17. Fotometría de grupos compactos de galaxias: Shakhbazian 37, 45, 166, 331 y 362

    NASA Astrophysics Data System (ADS)

    Campos, J. M.; Calderón, J. H.; Gimeno, N. G.; Díaz, R. J.

    Continuando con la fotometría CCD de Grupos de Galaxias Compactos de Shakhbazyan (SCGG) en este trabajo se presentan nuevos resultados preliminares sobre los grupos Shakbazyan 37, 45, 166, 331 y 362. EL objeto del proyecto es contribuir al estudio de las propiedades físicas de tales grupos y contribuir a las bases de datos para mejora de las estadísticas. Los datos fueron adquiridos con el Telescopio JKT del Observatorio Norte Europeo. El análisis de las imágenes en las bandas I y B como del índice de color B-I permitió reidentificar las galaxias catalogadas, resultando las mismas muy enrojecidas y verificando que predominan las galaxias tempranas, resultados consistentes con los obtenidos para otros grupos y por otros autores.

  18. Observación solar desde el espacio, resultados recientes

    NASA Astrophysics Data System (ADS)

    Machado, M. E.

    Presentaremos un resumen de los resultados más recientes sobre la física del sol, obtenidos por medio del análisis de datos de satélites artificiales como el Yohkoh, SOHO y COMPTON/GRO. En particular, nos referiremos a la acción y dinámica de los campos magnéticos en la generación de fenómenos activos y el calentamiento coronal.

  19. Astronomía y Física: un matrimonio Sartriano

    NASA Astrophysics Data System (ADS)

    Vucetich, H.

    Desde el siglo XVII, Física y Astronomía han formado un matrimonio similar al de Sartre y Beauvoir: lleno de amores contingentes, pero firme y duradero. En la charla examino tres de los frutos más recientes de este matrimonio: - La confirmación de la Relatividad General con datos astronómicos. - Astrofísica y Física de neutrinos. - Teorías de supercuerdas y astronomía.

  20. Ponte en onda: prende la energía limpia, (Spanish) Get Current

    SciTech Connect

    2015-05-01

    Cambiar a tecnologías de energía limpia significa que fortalecemos la economía y protegemos al medio ambiente. Este libreto de actividades educativas para todas las edades promueve el uso consciente de la energía, con datos de distintas formas de energía aplicables y una variedad de rompecabezas y crucigramas en temas energéticos.

  1. El medio interestelar alrededor de estrellas Of: HD 108

    NASA Astrophysics Data System (ADS)

    Cappa, C.; Testori, J. C.

    Hemos analizado la distribución del hidrógeno neutro interestelar en la vecindad de la estrella Of HD 108 en base a perfiles de la línea de 21 cm. Estos datos nos han permitido encontrar una probable burbuja interestelar asociada a la estrella. Comparamos estos resultados con la emisión en otros rangos espectrales y estimamos los principales parámetros físicos de la estructura.

  2. Ajuste de parámetros libres en teorías de campos camaleones a partir de espectros de nubes moleculares galácticas y experimentos terrestres

    NASA Astrophysics Data System (ADS)

    Teppa Pannia, F. A.; Landau, S. J.

    Resultados recientes, basados en el análisis de espectros moleculares de nubes galácticas a través del método del amoníaco, han arrojado nuevos límites sobre la variación del parámetro adimensional μ=m_e /m_p. Los resultados indican Δ μ/μ = (μ_{obs}-μ_{lab})/μ_{lab}= (2.2± 0.4_{est} ±0.3_{sist}) times 10 ^{-8}, en acuerdo con una variación no nula de dicha cantidad (Levshakov et al. 2010). En este trabajo, motivado por los datos astronómicos, estudiamos la solución lineal del modelo teórico fenomenológico de campo escalar camaleón, presentado por Mota y Shaw (2007), que predice variaciones en μ. Con el fin de cotejar estas predicciones con los resultados observacionales, utilizamos datos de experimentos terrestres que testean violaciones al Principio de Equivalencia para analizar el valor de los parámetros libres presentes en el modelo. El trabajo realizado muestra que la solución estudiada no se puede ajustar a los datos experimentales, sugiriendo que el modelo lineal debe ser descartado para explicar las observaciones astronómicas. FULL TEXT IN SPANISH

  3. Medición de placas astrométricas obtenidas con el telescopio Astrográfico de La Plata

    NASA Astrophysics Data System (ADS)

    di Sisto, R. P.; Orellana, R.

    El Observatorio de La Plata cuenta con un gran número de placas de asteroides y cometas obtenidas con el telescopio astrográfico, que cubren gran parte del cielo del hemisferio sur. En 1996 se recopilaron y clasificaron 2187 placas (Beca para estudiantes de la AAA 1996) de las cuales 2031 corresponden a asteroides. Los datos de cada placa se volcaron en una base de datos creada para facilitar su manejo y preservar la información. A partir de este trabajo se revisaron los MPC electrónicos y se identificaron aquellas placas de asteroides pertenecientes a nuestra base de datos cuyos resultados no fueron publicados en los mismos. De un total de 400 placas que no aparecían publicadas sobresalía un paquete constituído por 40 placas obtenidas en 1977. Estas últimas fueron reducidas utilizando las posiciones y movimientos propios de las estrellas de referencia obtenidas del catálogo SAO 2000 dadas para el sistema FK5. Las posiciones calculadas fueron enviadas y publicadas en los Minor Planet Circulars (MPC).

  4. Relevamiento total del hemisferio sur celeste en la frecuencia de 1420 MHz

    NASA Astrophysics Data System (ADS)

    Bava, J. A.; Colomb, F. R.; Hurrel, E.; Larrarte, J. J.; Sanz, A. J.; Testori, J. C.; Reich, P.; Reich, W.; Wielebinski, R.

    En el presente artículo se describe el relevamiento del cielo en el Hemisferio Sur Celeste en la frecuencia de 1420 MHz para declinaciones δ<= -19o realizado con la Antena II de 30 metros de diámetro del IAR. Este relevamiento posee igual sensibilidad (3xr.m.s=50 mK) que el realizado en el Hemisferio Norte con el radiotelescopio de 25 metros de Stockert de la Universidad de Bonn, operado por el Max-Planck Institute für Radioastronomie ( Reich W., 1982, A&ASS 48, 219; Reich P. and Reich W., 1986, A&ASS 63, 205). Con los datos obtenidos por ambos radiotelescopios se posee una base de datos de todo el cielo en esta frecuencia. En esta publicación presentamos los detalles del sistema receptor, técnicas de observación y reducción de datos, calibración y discusión de los errores en los resultados.

  5. La salud en personas con discapacidad intelectual en España: estudio europeo POMONA-II

    PubMed Central

    Martínez-Leal, Rafael; Salvador-Carulla, Luis; Gutiérrez-Colosía, Mencía Ruiz; Nadal, Margarida; Novell-Alsina, Ramón; Martorell, Almudena; González-Gordón, Rodrigo G.; Mérida-Gutiérrez, M. Reyes; Ángel, Silvia; Milagrosa-Tejonero, Luisa; Rodríguez, Alicia; García-Gutiérrez, Juan C.; Pérez-Vicente, Amado; García-Ibáñez, José; Aguilera-Inés, Francisco

    2011-01-01

    Introducción Estudios internacionales demuestran que existe un patrón diferenciado de salud y una disparidad en la atención sanitaria entre personas con discapacidad intelectual (DI) y población general. Objetivo Obtener datos sobre el estado de salud de las personas con DI y compararlos con datos de población general. Pacientes y métodos Se utilizó el conjunto de indicadores de salud P15 en una muestra de 111 sujetos con DI. Los datos de salud encontrados se compararon según el tipo de residencia de los sujetos y se utilizó la Encuesta Nacional de Salud 2006 para comparar estos datos con los de la población general. Resultados La muestra con DI presentó 25 veces más casos de epilepsia y el doble de obesidad. Un 20% presentó dolor bucal, y existió una alta presencia de problemas sensoriales, de movilidad y psicosis. Sin embargo, encontramos una baja presencia de patologías como la diabetes, la hipertensión, la osteoartritis y la osteoporosis. También presentaron una menor participación en programas de prevención y promoción de la salud, un mayor número de ingresos hospitalarios y un uso menor de los servicios de urgencia. Conclusiones El patrón de salud de las personas con DI difiere del de la población general, y éstas realizan un uso distinto de los servicios sanitarios. Es importante el desarrollo de programas de promoción de salud y de formación profesional específicamente diseñados para la atención de personas con DI, así como la implementación de encuestas de salud que incluyan datos sobre esta población. PMID:21948011

  6. The roles of birds, lizards, and rodents as hosts for the western black-legged tick Ixodes pacificus.

    PubMed

    Eisen, Lars; Eisen, Rebecca J; Lane, Robert S

    2004-12-01

    We compared the infestation by ixodid ticks of lizards, rodents, and birds collected simultaneously within areas representing common habitat types in Mendocino County, CA. Lizards were infested only by Ixodes pacificus Cooley and Kohls, birds by I. pacificus and Haemaphysalis leporispalustris (Packard), and rodents by I. pacificus, I. spinipalpis Hadwen and Nuttall, I. woodi Bishopp, Dermacentor occidentalis Marx, and D. variabilis (Say). Infestation by I. pacificus larvae and nymphs of lizards (Sceloporus occidentalis Baird and Girard; Elgaria spp.) and western gray squirrels (Sciurus griseus Ord) (means of 9-35 larvae and 5-6 nymphs per animal) was several times greater than for Neotoma fuscipes Baird woodrats, Peromyscus spp. mice, and birds (means of 0.9-3.5 larvae and 0-0.3 nymphs). Overall, Borrelia-refractory lizards accounted for 84% of I. pacificus larvae and 91% of nymphs collected from animals in dense woodlands. Bird species frequently utilizing tick-questing substrates such as leaf litter (guild I birds) were more heavily infested by I. pacificus subadults (5.2 larvae and 1.0 nymphs per bird) than guild IV birds with minimal perceived contact with tick-questing substrates (0.08 larvae and 0.06 nymphs per bird). Notably, guild I birds carried similar larval loads and at least 20-fold higher nymphal loads relative to woodrats and mice. Only guild IV birds carried as few I. pacificus nymphs as did these rodents. The ratios of larvae to nymphs suggest that, relative to birds, lizards, and squirrels (infested by 1.3-6.0 larvae per nymph), nocturnally active ground-dwelling rodents such as woodrats and mice are underutilized by the nymphal stage (69 to >100 larvae per nymph). The western gray squirrel and guild I-II birds (e.g., the dark-eyed junco, Junco hyemalis [L.]) were the only potential reservoirs of Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt, and Brenner (the causative agent of Lyme disease in North America) that were frequently infested

  7. Survey for evidence of Colorado tick fever virus outside of the known endemic area in California.

    PubMed

    Lane, R S; Emmons, R W; Devlin, V; Dondero, D V; Nelson, B C

    1982-07-01

    A virus very similar or identical to Colorado tick fever (CTF) virus was recovered from the blood clot of one of 104 black-tailed jack rabbits (Lepus californicus) examined during a survey for various zoonotic agents in mammals and ticks from the University of California, Hopland Field Station, Mendocino County, California, 1974--79. This is the first reported isolation of a CTF-like virus from L. californicus, and only the second time such a virus has been found in northwestern California. Mendocino County is located far outside the known distributional ranges of the most common mammalian hosts of CTF virus and of Dermacentor andersoni, the only proven tick vector for man. The viral isolate is very similar to a CTF-like virus previously recovered from the blood and spleen of a western gray squirrel (Sciurus griseus) from San Luis Obispo County, an area also outside of the previously-known CTF area. Virus was not isolated from 14 additional species of mammals (354 specimens) or from eight species of ticks (4,487 individuals), but CTF-neutralizing antibodies were detected in 28 of 771 (3.6%) sera from seven of 15 mammalian species including significant titers (greater than or equal to 1:8) in two species and one subspecies not previously reported as natural hosts, i.e., brush mouse (Peromyscus boylii), pinyon mouse (P. truei), and Columbian black-tailed deer (Odocoileus hemionus columbianus). CTF indirect immunofluorescent antibodies also were detected in 26 of 129 (20.2%) sera belonging to four of five mammalian species tested. Neutralizing antibodies were found in sera of deer from other localities in Mendocino County, from a deer mouse from Napa County, and from a brush rabbit from Monterey County as well. These findings suggest that a virus identical or similar to CTF virus is widespread in northwestern-westcentral California, and that surveillance for human cases of CTF or a similar disease should be extended to cover this region. PMID:7102919

  8. Composition of glycosaminoglycans in elasmobranchs including several deep-sea sharks: identification of chondroitin/dermatan sulfate from the dried fins of Isurus oxyrinchus and Prionace glauca.

    PubMed

    Higashi, Kyohei; Takeuchi, Yoshiki; Mukuno, Ann; Tomitori, Hideyuki; Miya, Masaki; Linhardt, Robert J; Toida, Toshihiko

    2015-01-01

    Shark fin, used as a food, is a rich source of glycosaminoglyans (GAGs), acidic polysaccharides having important biological activities, suggesting their nutraceutical and pharmaceutical application. A comprehensive survey of GAGs derived from the fin was performed on 11 elasmobranchs, including several deep sea sharks. Chondroitin sulfate (CS) and hyaluronic acid (HA) were found in Isurus oxyrinchus, Prionace glauca, Scyliorhinus torazame, Deania calcea, Chlamydoselachus anguineus, Mitsukurina owatoni, Mustelus griseus and Dasyatis akajei, respectively. CS was only found from Chimaera phantasma, Dalatias licha, and Odontaspis ferox, respectively. Characteristic disaccharide units of most of the CS were comprised of C- and D-type units. Interestingly, substantial amount of CS/dermatan sulfate (DS) was found in the dried fin (without skin and cartilage) of Isurus oxyrinchus and Prionace glauca. 1H-NMR analysis showed that the composition of glucuronic acid (GlcA) and iduronic acid (IdoA) in shark CS/DS was 41.2% and 58.8% (Isurus oxyrinchus), 36.1% and 63.9% (Prionace glauca), respectively. Furthermore, a substantial proportion of this CS/DS consisted of E-, B- and D-type units. Shark CS/DS stimulated neurite outgrowth of hippocampal neurons at a similar level as DS derived from invertebrate species. Midkine and pleiotrophin interact strongly with CS/DS from Isurus oxyrinchus and Prionace glauca, affording Kd values of 1.07 nM, 6.25 nM and 1.70 nM, 1.88 nM, respectively. These results strongly suggest that the IdoA-rich domain of CS/DS is required for neurite outgrowth activity. A detailed examination of oligosaccharide residues, produced by chondroitinase ACII digestion, suggested that the IdoA and B-type units as well as A- and C-type units were found in clusters in shark CS/DS. In addition, it was discovered that the contents of B-type units in these IdoA-rich domain increased in a length dependent manner, while C- and D-type units were located particularly in the

  9. Novel marine actinobacteria from emerald Andaman & Nicobar Islands: a prospective source for industrial and pharmaceutical byproducts

    PubMed Central

    2013-01-01

    Background Andaman and Nicobar Islands situated in the eastern part of Bay of Bengal are one of the distinguished biodiversity hotspot. Even though number of studies carried out on the marine flora and fauna, the studies on actinobacteria from Andaman and Nicobar Islands are meager. The aim of the present study was to screen the actinobacteria for their characterization and identify the potential sources for industrial and pharmaceutical byproducts. Results A total of 26 actinobacterial strains were isolated from the marine sediments collected from various sites of Port Blair Bay where no collection has been characterized previously. Isolates were categorized under the genera: Saccharopolyspora, Streptomyces, Nocardiopsis, Streptoverticillium, Microtetraspora, Actinopolyspora, Actinokineospora and Dactylosporangium. Majority of the isolates were found to produce industrially important enzymes such as amylase, protease, gelatinase, lipase, DNase, cellulase, urease and phosphatase, and also exhibited substantial antibacterial activity against human pathogens. 77% of isolates exhibited significant hemolytic activity. Among 26 isolates, three strains (NIOT-VKKMA02, NIOT-VKKMA22 and NIOT-VKKMA26) were found to generate appreciable extent of surfactant, amylase, cellulase and protease enzyme. NIOT-VKKMA02 produced surfactant using kerosene as carbon source and emulsified upto E24–63.6%. Moreover, NIOT-VKKMA02, NIOT-VKKMA22 and NIOT-VKKMA26 synthesized 13.27 U/ml, 9.85 U/ml and 8.03 U/ml amylase; 7.75 U/ml, 5.01 U/ml and 2.08 U/ml of cellulase and 11.34 U/ml, 6.89 U/ml and 3.51 U/ml of protease enzyme, respectively. Conclusions High diversity of marine actinobacteria was isolated and characterized in this work including undescribed species and species not previously reported from emerald Andaman and Nicobar Islands, including Streptomyces griseus, Streptomyces venezuelae and Saccharopolyspora salina. The enhanced salt, pH and temperature tolerance of the actinobacterial

  10. Marine bird aggregations associated with the tidally-driven plume and plume fronts of the Columbia River

    NASA Astrophysics Data System (ADS)

    Zamon, Jeannette E.; Phillips, Elizabeth M.; Guy, Troy J.

    2014-09-01

    Freshwater discharge from large rivers into the coastal ocean creates tidally-driven frontal systems known to enhance mixing, primary production, and secondary production. Many authors suggest that tidal plume fronts increase energy flow to fish-eating predators by attracting planktivorous fishes to feed on plankton aggregated by the fronts. However, few studies of plume fronts directly examine piscivorous predator response to plume fronts. Our work examined densities of piscivorous seabirds relative to the plume region and plume fronts of the Columbia River, USA. Common murres (Uria aalge) and sooty shearwaters (Puffinus griseus) composed 83% of all birds detected on mesoscale surveys of the Washington and Oregon coasts (June 2003-2006), and 91.3% of all birds detected on fine scale surveys of the plume region less than 40 km from the river mouth (May 2003 and 2006). Mesoscale comparisons showed consistently more predators in the central plume area compared to the surrounding marine area (murres: 10.1-21.5 vs. 3.4-8.2 birds km-2; shearwaters: 24.2-75.1 vs. 11.8-25.9 birds km-2). Fine scale comparisons showed that murre density in 2003 and shearwater density in both 2003 and 2006 were significantly elevated in the tidal plume region composed of the most recently discharged river water. Murres tended to be more abundant on the north face of the plume. In May 2003, more murres and shearwaters were found within 3 km of the front on any given transect, although maximum bird density was not necessarily found in the same location as the front itself. Predator density on a given transect was not correlated with frontal strength in either year. The high bird densities we observed associated with the tidal plume demonstrate that the turbid Columbia River plume does not necessarily provide fish with refuge from visual predators. Bird predation in the plume region may therefore impact early marine survival of Pacific salmon (Oncorhynchus spp.), which must migrate through the

  11. Cycloheximide: No Ordinary Bitter Stimulus

    PubMed Central

    Hettinger, Thomas P.; Formaker, Bradley K.; Frank, Marion E.

    2007-01-01

    Cycloheximide (CyX), a toxic antibiotic with a unique chemical structure generated by the actinomycete, Streptomyces griseus, has emerged as a primary focus of studies on mammalian bitter taste. Rats and mice avoid it at concentrations well below the thresholds for most bitter stimuli and T2R G-protein-coupled receptors specific for CyX with appropriate sensitivity are identified for those species. Like mouse and rat, golden hamsters, Mesocricetus auratus, also detected and rejected micromolar levels of CyX, although 1 mM CyX failed to activate the hamster chorda tympani nerve. Hamsters showed an initial tolerance for 500 μM CyX, but after that, avoidance of CyX dramatically increased, plasticity not reported for rat or mouse. As the hamster lineage branches well before division of the mouse-rat lineage in evolutionary time, differences between hamster and mouse-rat reactions to CyX are not surprising. Furthermore, unlike hamster LiCl-induced learned aversions, the induced CyX aversion neither specifically nor robustly generalized to other non-ionic bitter stimuli; and unlike adverse reactions to other chemosensory stimuli, aversions to CyX were not mollified by adding a sweetener. Thus, CyX is unlike other bitter stimuli. The gene for the high-affinity CyX receptor is a member of a cluster of 5 orthologous T2R genes that are likely rodent specific; this “CyX clade” is found in the mouse, rat and probably hamster, but not in the human or rabbit genome. The rodent CyX-T2R interaction may be one of multiple lineage-specific stimulus-receptor interactions reflecting a response to a particular environmental toxin. The combination of T2R multiplicity, species divergence and gene duplication results in diverse ligands for multiple species-specific T2R receptors, which confounds definition of ‘bitter’ stimuli across species. PMID:17400304

  12. Composition of Glycosaminoglycans in Elasmobranchs including Several Deep-Sea Sharks: Identification of Chondroitin/Dermatan Sulfate from the Dried Fins of Isurus oxyrinchus and Prionace glauca

    PubMed Central

    Higashi, Kyohei; Takeuchi, Yoshiki; Mukuno, Ann; Tomitori, Hideyuki; Miya, Masaki; Linhardt, Robert J.; Toida, Toshihiko

    2015-01-01

    Shark fin, used as a food, is a rich source of glycosaminoglyans (GAGs), acidic polysaccharides having important biological activities, suggesting their nutraceutical and pharmaceutical application. A comprehensive survey of GAGs derived from the fin was performed on 11 elasmobranchs, including several deep sea sharks. Chondroitin sulfate (CS) and hyaluronic acid (HA) were found in Isurus oxyrinchus, Prionace glauca, Scyliorhinus torazame, Deania calcea, Chlamydoselachus anguineus, Mitsukurina owatoni, Mustelus griseus and Dasyatis akajei, respectively. CS was only found from Chimaera phantasma, Dalatias licha, and Odontaspis ferox, respectively. Characteristic disaccharide units of most of the CS were comprised of C- and D-type units. Interestingly, substantial amount of CS/dermatan sulfate (DS) was found in the dried fin (without skin and cartilage) of Isurus oxyrinchus and Prionace glauca. 1H-NMR analysis showed that the composition of glucuronic acid (GlcA) and iduronic acid (IdoA) in shark CS/DS was 41.2% and 58.8% (Isurus oxyrinchus), 36.1% and 63.9% (Prionace glauca), respectively. Furthermore, a substantial proportion of this CS/DS consisted of E-, B- and D-type units. Shark CS/DS stimulated neurite outgrowth of hippocampal neurons at a similar level as DS derived from invertebrate species. Midkine and pleiotrophin interact strongly with CS/DS from Isurus oxyrinchus and Prionace glauca, affording Kd values of 1.07 nM, 6.25 nM and 1.70 nM, 1.88 nM, respectively. These results strongly suggest that the IdoA-rich domain of CS/DS is required for neurite outgrowth activity. A detailed examination of oligosaccharide residues, produced by chondroitinase ACII digestion, suggested that the IdoA and B-type units as well as A- and C-type units were found in clusters in shark CS/DS. In addition, it was discovered that the contents of B-type units in these IdoA-rich domain increased in a length dependent manner, while C- and D-type units were located particularly in the

  13. Marine bird and cetacean associations with bathymetric habitats and shallow-water topographies: implications for trophic transfer and conservation

    NASA Astrophysics Data System (ADS)

    Yen, Peggy P. W.; Sydeman, William J.; Hyrenbach, K. David

    2004-09-01

    We investigated the aggregative response of marine birds and cetaceans to bathymetric features in central California over 4 years, 1996-1997 and 2001-2002. A total of 1700 km 2 of ocean habitat was surveyed over six cruises. We considered the distribution of the most abundant marine birds and mammals in relation to bathymetry. We focused our analyses on eight focal taxa: Cassin's auklet ( Ptychoramphus aleuticus), common murre ( Uria aalge), sooty shearwater ( Puffinus grieus), phalarope species (red, and red-necked: Phalaropus fulicaria, Phalaropus lobatus), Dall's porpoise ( Phocoenoides dalli), Pacific white-sided dolphin ( Lagenorhynchus obliquidens), humpback whale ( Megaptera novaeangliae), and Risso's dolphin ( Grampus griseus). We evaluated associations of top predators with seven bathymetric indices and three distance measurements to shallow-water topographies. The bathymetric descriptors included (1) median depth, (2) depth coefficient of variation, (3) contour index, and shortest distance to (4) the mainland, (5) the continental shelf-break (200-m isobath), (6) the continental slope (1000-m isobath), and (7) pelagic waters (3000-m isobath). The measurements of shallow water topographies included the shortest distance to: (8) the Cordell Bank seamount, (9) the Farallon Island Archipelago (a breeding colony for auklets and murres), and (10) Monterey Canyon. We documented two instances of spatial autocorrelation (for Cassin's auklet and common murre) at lags (distances) of 0-3 and 3-9 km, respectively, and accounted for this spatial pattern in analyses of habitat associations. We found similar relationships between cetaceans and bathymetric features at both interannual and weekly time scales. Seabirds revealed both persistent and variable relationships through time. For the resident breeding murres, we detected an interannual trend in habitat use, with these birds shifting their distribution offshore over time. Our study demonstrates that resident and

  14. Post-settlement Life Cycle Migration Patterns and Habitat Preference of Coral Reef Fish that use Seagrass and Mangrove Habitats as Nurseries

    NASA Astrophysics Data System (ADS)

    Cocheret de la Morinière, E.; Pollux, B. J. A.; Nagelkerken, I.; van der Velde, G.

    2002-08-01

    Mangroves and seagrass beds have received considerable attention as nurseries for reef fish, but comparisons have often been made with different methodologies. Thus, relative importance of different habitats to specific size-classes of reef fish species remains unclear. In this study, 35 transects in 11 sites of mangroves, seagrass beds and coral reef were surveyed daily, in and in front of a marine bay on the island of Curaçao (Netherlands Antilles). The density and size-frequency of nine reef fish species (including herbivores, zoobenthivores and piscivores) was determined during a five-month period using a single methodology, viz. underwater visual census. All species were ' nursery species ' in terms of their high densities of juveniles in mangroves or seagrass beds. Relative density distribution of the size-classes of the selected species over mangroves and seagrass beds suggested high levels of preference for either mangroves or seagrass beds of some species, while other species used both habitats as a nursery. Spatial size distribution of the nine species suggested three possible models for Post-settlement Life Cycle Migrations (PLCM). Haemulon sciurus, Lutjanus griseus, L. apodus, and Acanthurus chirurgus appear to settle and grow up in bay habitats such as mangroves and seagrass beds, and in a later stage migrate to the coral reef (Long Distance PLCM). Juveniles of Acanthurus bahianus and Scarus taeniopterus were found only in bay habitats at close proximity to the coral reef or on the reef itself, and their migration pattern concerns a limited spatial scale (Short Distance PLCM). Some congeneric species carry out either Long Distance PLCM or Short Distance PLCM, thereby temporarily alleviating competition in reef habitats. Haemulon flavolineatum, Ocyurus chrysurus and Scarus iserti displayed a Stepwise PLCM pattern in which smallest juveniles dwell in the mouth of the bay, larger individuals then move to habitats deeper into the bay, where they grow up

  15. Ocean warming and seabird communities of the southern California Current System (1987-98): response at multiple temporal scales

    NASA Astrophysics Data System (ADS)

    Hyrenbach, K. David; Veit, Richard R.

    2003-08-01

    Declines in ocean productivity and shifts in species assemblages along the West Coast of North America during the second half of the XXth century have been attributed to the concurrent warming of the California Current. This paper addresses changes in the avifauna off southern California between May 1987 and September 1998, in response to shifting water mass distributions over short (<1 year) and long (interannual) temporal scales. More specifically, our research focuses on the relative importance of distinct foraging guilds and species assemblages with an affinity for warm and cold water. Over the long term, the avifauna off southern California shifted from a 'high-productivity' community typical of eastern boundary upwelling systems, to a 'low-productivity' assemblage similar to those inhabiting the subtropical gyres. Overall seabird abundance decreased; the relative importance of cold-water seabirds that dive in pursuit of prey declined; and warm-water species that feed at the surface and plunge to capture prey became more numerous. These community-level changes are consistent with the northward shifts in species ranges and the declining ocean productivity anticipated as a result of global warming. However, the response of individual taxa with an affinity for warm-water and cold-water conditions has been more difficult to predict, due to differences in species-specific responses to ocean warming. The three cold-water species investigated (Sooty Shearwater Puffinus griseus, Cassin's Auklet Ptychoramphus aleuticus, and Rhinoceros Auklet Cerorhinca monocerata) decreased in abundance during this study. On the other hand, only one of the six warm-water species considered (Pink-footed Shearwater, Puffinus creatopus) increased significantly over the long term. Yet, the warm-water Leach's Storm-petrel ( Oceanodroma leucorhoa) increased between 1987 and 1993, and then declined between 1994 and 1998. Moreover, cross-correlations between seasonally adjusted anomalies of

  16. At-sea distribution and abundance of seabirds off southern California: A 20-year comparison

    USGS Publications Warehouse

    Mason, J.W.; McChesney, G.J.; McIver, W.R.; Carter, H.R.; Takekawa, J.Y.; Golightly, R.T.; Ackerman, J.T.; Orthmeyer, D.L.; Perry, W.M.; Yee, J.L.; Pierson, M.O.; McCrary, M.D.

    2007-01-01

    We conducted aerial at-sea and coastal surveys to examine the distribution and abundance of seabirds off southern California, from Cambria, California, to the Mexican border. From May 1999-January 2002, we flew 102 d, covered >54,640 km of transect lines, and conducted nine complete surveys of southern California in January, May, and September. We identified 54 species comprising 12 families and counted >135,000 individuals. Seabird densities were greater along island and mainland coastlines than at sea and were usually greatest in January surveys. Densities were greatest at sea near the northern Channel Islands in January and north of Point Conception in May, and lowest in the southwestern portion of the Southern California Bight in all survey months. On coastal transects, seabird densities were greatest along central and southern portions of the mainland coastline from Point Arguello to Mexico. We estimated that 981,000 ?? 144,000 (x?? ?? SE) seabirds occurred in the study area in January, 862,000 ?? 95,000 in May, and 762,000 ?? 72,000 in September. California Gulls (Larus californicus), Western Grebes (Aechmophorus occidentalis), and Cassin's Auklets (Ptychoramphus aleuticus) were most abundant in January surveys at sea, whereas Sooty and Short-tailed shearwaters (Puffinus griseus and P. tenuirostris), phalaropes (Phalaropus spp.), and Western Gulls (Larus. occidentalis) were most abundant in May and September surveys. On coastal transects, California Gulls, Western Grebes, Western Gulls, and Surf Scoters (Melanitta perspicillata) were most abundant in January; Western Grebes, Western Gulls, Surf Scoters, and Brown Pelicans (Pelecanus occidentalis) were most abundant in May; and Sooty Shearwaters, Short-tailed Shearwaters, Western Gulls, Western Grebes, Brown Pelicans, and Heermann's Gulls (Larus heermanni) were most abundant in September. Compared to historical seabird densities collected in the same area two decades ago (1975-1978 and 1980-1983), abundance

  17. Top-down and bottom-up factors affecting seabird population trends in the California current system (1985-2006)

    NASA Astrophysics Data System (ADS)

    Ainley, David G.; David Hyrenbach, K.

    2010-03-01

    To characterize the environmental factors affecting seabird population trends in the central portion of the California current system (CCS), we analyzed standardized vessel-based surveys collected during the late spring (May-June) upwelling season over 22 yr (1985-2006). We tested the working hypothesis that population trends are related to species-specific foraging ecology, and predicted that temporal variation in population size should be most extreme in diving species with higher energy expenditure during foraging. We related variation in individual species abundance (number km -2) to seasonally lagged (late winter, early spring, late spring) and concurrent ocean conditions, and to long-term trends (using a proxy variable: year) during a multi-decadal period of major fluctuations in the El Niño-Southern oscillation (ENSO) and the Pacific decadal oscillation (PDO). We considered both remote (Multivariate ENSO Index, PDO) and local (coastal upwelling indices and sea-surface temperature) environmental variables as proxies for ocean productivity and prey availability. We also related seabird trends to those of potentially major trophic competitors, humpback ( Megaptera novaeangliae) and blue ( Balaenoptera musculus) whales, which increased in number 4-5-fold midway during our study. Cyclical oscillations in seabird abundance were apparent in the black-footed albatross ( Phoebastria nigripes), and decreasing trends were documented for ashy storm-petrel ( Oceanodroma homochroa), pigeon guillemot ( Cepphus columbus), rhinoceros auklet ( Cerorhinca monocerata), Cassin’s auklet ( Ptychoramphus aleuticus), and western gull ( Larus occidentalis); the sooty shearwater ( Puffinus griseus), exhibited a marked decline before signs of recovery at the end of the study period. The abundance of nine other focal species varied with ocean conditions, but without decadal or long-term trends. Six of these species have the largest global populations in the CCS, and four are highly

  18. Plectorhinchus caeruleonothus, a new species of sweetlips (Perciformes:
    Haemulidae) from northern Australia and the resurrection of P. unicolor (Macleay, 1883), species previously confused with P. schotaf (Forsskål, 1775).

    PubMed

    Johnson, Jeffrey W; Wilmer, Jessica Worthington

    2015-01-01

    Two distinct haemulid fishes from Australia and the Indo-Australian Archipelago respectively have long been confused with Plectorhinchus schotaf (Forsskål, 1775). Plectorhinchus caeruleonothus sp. nov. is described from 17 specimens collected off western and far northern Australia, between the Monte Bello Islands, Western Australia and Torres Strait, Queensland. It has also been confirmed outside this range by photographs taken at Ningaloo Reef and Exmouth Gulf, Western Australia, and at Claremont Isles and Lizard Island, Queensland. The new species is unique among the genus in having a combination of dorsal-fin rays XII, 18-20, lateral-line scales 56-61, gill rakers 7-9 on the upper limb and 18-20 on the lower limb of the first arch, nostrils minute, and fresh colouration in adults including body uniformly grey, cheek, opercles and posterior margin of the opercular membrane uniformly blue-grey, and rim of orbit and upper edge of maxilla dusky yellow. In contrast to its closest congeners, the juveniles have a distinctive pattern of narrow creamish-white to pale grey stripes on a dark grey to chocolate brown background on the head and body, and oblique dark stripes progressing with growth to spots on the caudal fin. Plectorhinchus unicolor (Macleay, 1883) from Japan to northern Australia is resurrected from the synonomy of P. schotaf and redescribed on the basis of the holotype and 24 non-type specimens. Plectorhinchus unicolor is most similar to P. schotaf, but can be distinguished by fresh colouration, modal dorsal and pectoral-fin ray counts and DNA barcoding. Plectorhinchus schotaf appears to be restricted to the region from southeast Africa to the Arabian Sea, including the Red Sea and Persian Gulf. Plectorhinchus griseus (Cuvier in Cuvier & Valenciennes, 1830) from Indian and Sri Lankan Seas has previously been treated as a junior synonym of P. schotaf, but in accordance with Smith (1962), is here confirmed as a valid species, readily distinguished from the

  19. Habitat use and preferences of cetaceans along the continental slope and the adjacent pelagic waters in the western Ligurian Sea

    NASA Astrophysics Data System (ADS)

    Azzellino, A.; Gaspari, S.; Airoldi, S.; Nani, B.

    2008-03-01

    The physical habitat of cetaceans occurring along the continental slope in the western Ligurian Sea was investigated. Data were collected from two different sighting platforms, one of the two being a whale-watching boat. Surveys, conducted from May to October and from 1996 to 2000, covered an area of approximately 3000 km 2 with a mean effort of about 10,000 km year -1. A total of 814 sightings was reported, including all the species occurring in the area: Stenella coeruleoalba, Balaenoptera physalus, Physeter macrocephalus, Globicephala melas, Grampus griseus, Ziphius cavirostris, Tursiops truncatus, Delphinus delphis. A Geographic Information System was used to integrate sighting data to a set of environmental characteristics, which included bottom gradient, area between different isobaths, and length and linearity of the isobaths within a cell unit. Habitat use was analysed by means of a multi-dimensional scaling, MDS, analysis. Significant differences were found in the habitat preference of most of the species regularly occurring in the area. Bottlenose dolphin, Risso's dolphin, sperm whale and Cuvier's beaked whale were found strongly associated to well-defined depth and slope gradient characteristics of the shelf-edge and the upper and lower slope. The hypothesis of habitat segregation was considered for Risso's dolphin, sperm whale and Cuvier's beaked whale. Canonical discriminant functions using depth and slope as predictors outlined clear and not overlapping habitat preferences for Risso's dolphin and Cuvier's beaked whale, whereas a partial overlapping of the habitat of the other two species was observed for sperm whale. Such a partitioning of the upper and lower slope area may be the result of the common feeding habits and suggests a possible competition of these three species. A temporal segregation in the use of the slope area was also observed for sperm whales and Risso's dolphins. Fin whales, and the occasionally encountered common dolphin and long

  20. Shorebird roost-site selection at two temporal scales: Is human disturbance a factor?

    USGS Publications Warehouse

    Peters, K.A.; Otis, D.L.

    2007-01-01

    1. Roost-site selection in shorebirds is governed by ambient factors, including environmental conditions and human disturbance. Determination of the extent to which these factors affect roost use and the associated implications for shorebird habitat protection is important for conservation strategies and informed management of human recreational use of these habitats. Shorebird conservation as a whole is a high priority world-wide because a large proportion of shorebird species is in decline. However, little is understood about the consistency of roost use by different species, what conditions affect species-specific roost-site selection, and at what spatial and temporal scales conditions influence selection. 2. We studied high-tide roost-site selection by eight species of non-breeding shorebirds on a critically important stopover and wintering refuge. We calculated spatial and temporal variability in roost use for each species based on counts and consistency of incidence. We then examined roost-site selection in relation to structural, environmental and human disturbance factors, and how this varied across spatial and temporal scales. 3. Most roosts were used less than 50% of the time, although larger roosts were used more consistently. This varied among species, with red knot Calidris canutus tending to concentrate at a few roosts and American oystercatcher Haematopus palliatus, dowitcher Limnodromus griseus and Limnodromus scolopaceus and ruddy turnstone Arenaria interpres more diffusely distributed among roosts. 4. At an annual scale, the principal factors affecting shorebird presence at roosts were roost length (size), local region, substrate and aspect. The extent and direction of these effects varied among species. Among years, red knots avoided roosts that had high average boat activity within 1000 m, but disturbance did not appear to be a factor for other species. 5. Daily roost use was influenced primarily by wind speed and the ability of roosts to

  1. Characterization of chito-oligosaccharides prepared by chitosanolysis with the aid of papain and Pronase, and their bactericidal action against Bacillus cereus and Escherichia coli

    PubMed Central

    2005-01-01

    Papain (from papaya latex; EC 3.4.22.2) and Pronase (from Streptomyces griseus; EC 3.4.24.31) caused optimum depolymerization of chitosan at pH 3.5 and 37 °C, resulting in LMMC (low molecular mass chitosan) and chito-oligomeric–monomeric mixture. The yield of the latter was 14–16% and 14–19% respectively for papain- and Pronase-catalysed reactions, depending on the reaction time (1–5 h). HPLC revealed the presence of monomer(s) and oligomers of DP (degree of polymerization) 2–6, which was also confirmed by matrix-assisted laser-desorption ionization–time-of-flight MS. Along with the chito-oligomers, the appearance of only GlcNAc (N-acetylglucosamine) in Pronase-catalysed chitosanolysis was indicative of its different action pattern compared with papain. Fourier-transform infrared, liquid-state 13C-NMR spectra and CD analyses of chito-oligomeric–monomeric mixture indicated the release of GlcNAc/GlcNAc-rich oligomers. The monomeric sequence at the non-reducing ends of chito-oligomers was elucidated using N-acetylglucosaminidase. The chito-oligomeric–monomeric mixture showed better growth inhibitory activity towards Bacillus cereus and Escherichia coli compared with native chitosan. Optimum growth inhibition was observed with chito-oligomers of higher DP having low degree of acetylation. The latter caused pore formation and permeabilization of the cell wall of B. cereus, whereas blockage of nutrient flow due to the aggregation of chito-oligomers–monomers was responsible for the growth inhibition and lysis of E. coli, which were evidenced by scanning electron microscopy analysis. The spillage of cytoplasmic enzymes and native PAGE of the cell-free supernatant of B. cereus treated with chito-oligomeric–monomeric mixture further confirmed bactericidal activity of the latter. Use of papain and Pronase, which are inexpensive and easily available, for chitosanolysis, is of commercial importance, as the products released are of considerable biomedical

  2. Hormonal control by A-factor of morphological development and secondary metabolism in Streptomyces

    PubMed Central

    Horinouchi, Sueharu; Beppu, Teruhiko

    2007-01-01

    Streptomyces griseus, a well-known industrial producer of streptomycin, is a member of the genus Streptomyces, which shows a complex life cycle resembling that of fungi. A-factor, a C13γ-butyrolactone compound, was discovered as a self-regulatory factor or a bacterial hormone to induce morphological differentiation and production of secondary metabolites, including streptomycin, in this organism. Accumulating evidence has revealed an A-factor-triggered signal cascade, which is composed of several key steps or components. These include: (i) AfsA catalyzing a crucial step of A-factor biosynthesis, (ii) the A-factor-specific receptor (ArpA), which acts as a transcriptional repressor for adpA, (iii) adpA, a sole target of ArpA, which encodes a global transcriptional activator AdpA, and (iv) a variety of members of the AdpA regulon, a set of the genes regulated by AdpA. A-factor is biosynthesized via five reaction steps, in which AfsA catalyzes acyl transfer between a β-ketoacyl-acyl carrier protein and the hydroxyl group of dihydroxyacetone phosphate. The receptor ArpA, belonging to the TetR family, is a homodimer, each subunit of which contains a helix-turn-helix DNA-binding motif and an A-factor-binding pocket. The three-dimensional structure and conformational change upon binding A-factor are elucidated, on the basis of X-ray crystallography of CprB, an ArpA homologue. AdpA, belonging to the AraC/XylS transcriptional activator family, binds operators upstream from the promoters of a variety of the target genes and activates their transcription, thus forming the AdpA regulon. Members of the AdpA regulon includes the pathway-specific transcriptional activator gene strR that activates the whole streptomycin biosynthesis gene cluster, in addition to a number of genes that direct the multiple cellular functions required for cellular differentiation in a concerted manner. A variety of A-factor homologues as well as homologues of afsA/arpA are distributed widely among

  3. Characterization of chito-oligosaccharides prepared by chitosanolysis with the aid of papain and Pronase, and their bactericidal action against Bacillus cereus and Escherichia coli.

    PubMed

    Vishu Kumar, Acharya B; Varadaraj, Mandyam C; Gowda, Lalitha R; Tharanathan, Rudrapatnam N

    2005-10-15

    Papain (from papaya latex; EC 3.4.22.2) and Pronase (from Streptomyces griseus; EC 3.4.24.31) caused optimum depolymerization of chitosan at pH 3.5 and 37 degrees C, resulting in LMMC (low molecular mass chitosan) and chito-oligomeric-monomeric mixture. The yield of the latter was 14-16% and 14-19% respectively for papain- and Pronase-catalysed reactions, depending on the reaction time (1-5 h). HPLC revealed the presence of monomer(s) and oligomers of DP (degree of polymerization) 2-6, which was also confirmed by matrix-assisted laser-desorption ionization-time-of-flight MS. Along with the chito-oligomers, the appearance of only GlcNAc (N-acetylglucosamine) in Pronase-catalysed chitosanolysis was indicative of its different action pattern compared with papain. Fourier-transform infrared, liquid-state 13C-NMR spectra and CD analyses of chito-oligomeric-monomeric mixture indicated the release of GlcNAc/GlcNAc-rich oligomers. The monomeric sequence at the non-reducing ends of chito-oligomers was elucidated using N-acetylglucosaminidase. The chito-oligomeric-monomeric mixture showed better growth inhibitory activity towards Bacillus cereus and Escherichia coli compared with native chitosan. Optimum growth inhibition was observed with chito-oligomers of higher DP having low degree of acetylation. The latter caused pore formation and permeabilization of the cell wall of B. cereus, whereas blockage of nutrient flow due to the aggregation of chito-oligomers-monomers was responsible for the growth inhibition and lysis of E. coli, which were evidenced by scanning electron microscopy analysis. The spillage of cytoplasmic enzymes and native PAGE of the cell-free supernatant of B. cereus treated with chito-oligomeric-monomeric mixture further confirmed bactericidal activity of the latter. Use of papain and Pronase, which are inexpensive and easily available, for chitosanolysis, is of commercial importance, as the products released are of considerable biomedical value. PMID

  4. Phospholipid protection against proteolysis of D-beta-hydroxybutyrate dehydrogenase, a lecithin-requiring enzyme.

    PubMed

    Maurer, A; McIntyre, J O; Churchill, S; Fleischer, S

    1985-02-10

    D-beta-Hydroxybutyrate dehydrogenase is a lipid-requiring enzyme which is localized on the inner face of the mitochondrial inner membrane. The apodehydrogenase, i.e. the purified enzyme devoid of lipid, has been purified from beef heart mitochondria and as such is inactive. It can be reactivated by insertion into phospholipid vesicles containing lecithin. Proteolytic digestion with different proteases has been carried out to obtain insight into the orientation of the enzyme in the membrane and to assess the extent of immersion of the protein into the phospholipid bilayer. Digestion of the apodehydrogenase with either trypsin, chymotrypsin, Staphylococcus aureus protease, thermolysin, carboxypeptidases A and Y, or Pronase (from Streptomyces griseus) leads to loss of activity, as assayed with phospholipid. Limited digestion with carboxypeptidase results in complete inactivation. Of the proteases tested, only Pronase and chymotrypsin cleave and inactivate the enzyme inserted into phospholipid vesicles (enzyme-phospholipid complex). For the enzyme-phospholipid complex, the loss of activity with Pronase digestion follows a single exponential decay to less than 10% of the initial activity. With chymotrypsin digestion, the staining intensity of the original approximately 31,500-dalton polypeptide decreases more rapidly than the loss of enzymic activity. The enzyme-phospholipid complex, after limited cleavage with chymotrypsin, retains enzymic activity and resonance energy transfer from protein to bound NADH and an approximately 26,000-dalton polypeptide is observed. Phospholipid alters the cleavage pattern with both chymotrypsin and Pronase, and the rate of inactivation of the enzyme-phospholipid complex is slowed in the presence of NAD(H). Moreover, the rate of inactivation of the apodehydrogenase with chymotrypsin is diminished approximately 3-fold in the presence of NAD+. Digestion of submitochondrial vesicles with either trypsin, chymotrypsin, or Pronase rapidly

  5. Regional characterisation of hydraulic properties of rock using air-lift data

    NASA Astrophysics Data System (ADS)

    Wladis, David; Gustafson, Gunnar

    les données disponibles présentent une certaine imprécision. Au départ, il faut cependant examiner l'utilité potentielle, c'est-à-dire la précision attendue, de données imprécises dans chaque cas spécifique. Cette étude analyse les possibilités d'obtenir des estimations de transmissivitéà partir de données d'air-lift dans des roches de socle en Suède, au mieux à un facteur 10 près par rapport aux données d'excellente qualité fournies par des essais d'injection. La précision attendue des résultats a été examinée analytiquement et grâce à des méthodes statistiques. Les résultats ont aussi été comparés aux données d'essais d'injection. Les résultats indiquent que les données obtenues par air-lift fournissent des estimations de transmissivitéà un facteur 10 près par comparaison avec celles des essais d'injection des exemples étudiés. L'étude montre aussi que la pénétration partielle et la fracturation hydraulique peuvent affecter les estimations seulement d'environ un facteur 5. Ainsi, le recours à des données existantes peut être économiquement plus intéressant que le recueil de nouvelles données dans les premières étapes des études hydrogéologiques. Resumen Los estudios hidrogeológicos, en general, y las estimaciones de propiedades hidráulicas en rocas, en particular, requieren gran cantidad de datos. En muchos países se han creado grandes bases de datos hidrogeológicos, recogidos y almacenados a lo largo de los años. Por tanto, el uso de los datos ya existentes, aunque imprecisos, puede suponer una alternativa barata a la recopilación de nuevos datos, particularmente en las primeras fases de un estudio hidrogeológico. Sin embargo la precisión y utilidad del método deben analizarse para cada caso específico. En este estudio se contempla la posibilidad de, a partir de datos de ensayos de inyección de aire realizados en Suecia, obtener valores estimativos de transmisividad dentro del orden de magnitud de los

  6. Actitudes de los candidatos y maestros de ciencias en servicio acerca del uso de las herramientas computadorizadas en las clases de ciencias

    NASA Astrophysics Data System (ADS)

    Bayuelo, Ezequiel

    Este estudio examino y comparo las actitudes de los candidatos a maestros de ciencias y los maestros de ciencias en servicio acerca de la utilizacion de las herramientas computadorizadas en las clases de ciencias. Tambien identifico y diferencio el uso que ellos dan a estas herramientas en las clases de ciencias. Este estudio presenta un diseno descriptivo exploratorio. Constituyeron la muestra trescientos diez sujetos que fueron candidatos a maestros de ciencias o maestros de ciencias en servicio. Para recoger los datos se construyo y valido un cuestionario de treinta y un itemes. Se utilizaron las pruebas estadisticas no parametricas Kruskal Wallis y Chi-cuadrado (test de homogeneidad) para establecer las diferencias entre las actitudes de los sujetos con relacion al uso de las herramientas computadorizadas en las clases de ciencias. Los hallazgos evidenciaron que son positivas y muy parecidas las actitudes de los candidatos a maestros y maestros en servicio hacia el uso de las herramientas computadorizadas. No hubo diferencias entre los candidatos y maestros en servicio en terminos de las actitudes de confianza y empatia hacia el uso de las herramientas computadorizadas en las clases de ciencias. En aspectos como el uso del banco de datos bibliografico Eric y el uso de las herramientas computadorizadas en actividades educativas como explorar conceptos, conceptuar, aplicar lo aprendido y hacer asignaciones hubo diferencias estadisticamente significativas entre los candidatos y los maestros en servicio. Al comparar las frecuencias observadas con las esperadas hubo mas maestros en servicio y menos candidatos que indicaron usar el anterior banco de datos y las herramientas computadorizadas en las mencionadas actividades educativas.

  7. [In Process Citation].

    PubMed

    Menal-Puey, Susana; Morán Del Ruste, Manuel; Marques-Lopes, Iva

    2016-01-01

    Introducción: una dieta vegetariana puede satisfacer las necesidades nutricionales si está bien planificada. En este sentido, los vegetarianos deben ser aconsejados para elegir alimentos alternativos a los productos de origen animal seleccionando el tamaño de porción adecuada de cada uno de ellos. El valor nutricional de las porciones de los alimentos vegetales tradicionales es bien conocido, sin embargo, el mercado vegetariano ofrece otros productos cuya composición química es menos conocida, ya que no son alimentos ampliamente consumidos por la población. Es necesario conocer tanto el contenido de nutrientes de las porciones de estos alimentos como la biodisponibilidad de estos nutrientes en la dieta vegetariana. Objetivos: este trabajo tiene como objetivo mejorar la información disponible sobre el aporte nutricional a la dieta de un adulto sano de las porciones de alimentos utilizados por la población vegetariana. Además, se discuten algunos puntos sobre la biodisponibilidad de los nutrientes más relevantes, y se proponen alternativas para mejorar su utilización. Métodos: los datos de composición de los alimentos veganos, por 100 g, se buscaron en bases de datos de composición de alimentos, y a partir de ellos se calculó la composición química de las porciones. Después, estos datos nutricionales se compararon con las ingestas dietéticas de referencia europeas para la población adulta, y se discutió la biodisponibilidad de los nutrientes más importantes. PMID:27238802

  8. Un nuevo estudio del cúmulo abierto Tr 14 en la región de Carina

    NASA Astrophysics Data System (ADS)

    García, B.; Malaroda, S.; Levato, H.; Morrell, N.

    Presentamos nuevos datos espectroscópicos de 9 objetos entre los miembros más brillantes de Tr 14. Hemos medido un total de 80 nuevos espectrogramas para contribuir a la determinación de la real naturaleza de estos objetos desde el punto de vista de la duplicidad. Del nuevo material debemos concluir que la mayoría de las estrellas en la muestra son simples. Sin embargo existen algunos objetos cuyo seguimiento debe continuar ya que no nos es posible efectuar conclusiones definitivas con el presente material.

  9. Resultados del relevamiento de HI en el Cielo Austral: 3. Relevamiento de Nubes de Alta Velocidad

    NASA Astrophysics Data System (ADS)

    Morras, R.; Bajaja, E.; Arnal, E. M.; Pöppel, W. G. L.

    Los resultados del relevamiento de HI del Hemisferio Austral fueron reprocesados con el fin de incrementar su sensibilidad. Así, se utilizó esta nueva base de datos con el fin de obtener un nuevo relevamiento de Nubes de Alta Velocidad en el cielo austral. El ruido r.m.s. alcanzado es de 0.015-0.020 K, con una resolución espectral de 8 km/seg. El cubrimiento espacial del relevamiento mejora en un factor 16 al realizado por Bajaja et al (1985).

  10. El medio interestelar alrededor de estrellas Of

    NASA Astrophysics Data System (ADS)

    Caballero, N.; Cappa, C.

    Se analiza la distribución del hidrógeno neutro interestelar en la vecindad de algunas estrellas Of con el fin de investigar la presencia de burbujas de H I vinculadas a las estrellas. Se determinan los parámetros físicos de las burbujas de H I encontradas y se comparan con estructuras similares vinculadas a estrellas Wolf-Rayet. El estudio se lleva a cabo en base a datos pertenecientes al relevamiento de Weaver y Willians (1973).

  11. Drug abuse relapse rates linked to level of education: can we repair hypodopaminergic-induced cognitive decline with nutrient therapy?

    PubMed

    Blum, Kenneth; Schoenthaler, Stephen J; Oscar-Berman, Marlene; Giordano, John; Madigan, Margaret A; Braverman, Eric R; Han, David

    2014-05-01

    It is well known that athletes and other individuals who have suffered painful injuries are at increased risk for all reward deficiency syndrome (RDS) behaviors, including substance use disorder (SUD). Comparing patient demographics and relapse rates in chemical dependence programs is pertinent because demographics may affect outcomes. Increased risk for relapse and lower academic achievement were found to have a significant association in recent outcome data from a holistic treatment center (HTC) located in North Miami Beach, FL. Relapse outcomes from the Drug Addiction Treatment Outcome Study (DATOS; n = 1738) and HTC (n = 224) were compared for a 12-month period. Post-discharge relapse was reported by 26% of HTC patients and 58% of patients in DATOS. When broken out by education level-less than high school, high school diploma, college degree, and graduate degree-HTC patient relapse was 50%, 36%, 33%, and 16%, respectively, and demonstrated an inverse linear association (F = 5.702; P = 0.017). Looking at DATOS patient relapse rates broken down by educational grades/years completed, patients who attended school between 7th grade and 4 years of college also demonstrated an inverse linear association (F = 5.563; P = 0.018). Additionally, the lowest performers, patients who reported their academic performance as "not so good," had the highest relapse (F = 4.226; P = 0.04). Albeit certain limitations, compared with DATOS patients, HTC patients produced significantly larger net differences in relapse rates (X 2 = 84.09; P = 0.0001), suggesting that other variables, such as the treatment model may also affect patient relapse. Our results implicate the use of vitamin and mineral supplements coupled with a well-researched natural dopamine agonist nutrient therapy; both have been shown to improve cognition and behavior, and thus academic achievement. That relapse is highest among addicts who have less education and who report lower grades is a factor that can be useful

  12. Cinética Química: el laboratorio

    NASA Astrophysics Data System (ADS)

    Cabañas Galán, B.

    La interpretación de las transformaciones químicas que se producen en la atmósfera requiere un profundo conocimiento de la cinética, productos y mecanismos de reacción de las posibles interacciones que pueden ocurrir entre las distintas especies presentes en ella. Información cuantitativa de este tipo es un prerrequisito para la construcción de modelos numéricos adecuados que expliquen el comportamiento químico-físico de la atmósfera. Esta información se obtiene a partir de experimentos realizados en laboratorios y por tanto independiente de medidas atmosféricas, por lo que los modelos atmosféricos derivados de ellos, pueden usarse para diagnosticar y predecir adecuadamente el comportamiento atmosférico. En esta exposición se recogen las técnicas experimentales más extendidas para la obtención de datos cinéticos así como los métodos de análisis de datos más utilizados en el estudio de las distintas reacciones de interés atmosférico. Se analizan sus características generales así como su adecuación a los distintos tipos de reacciones.

  13. Design of VLBI Array in South America

    NASA Astrophysics Data System (ADS)

    Carrara, E. A.; Abraham, Z.

    1990-11-01

    RESUMEN. Estudiamos la localizaci6n 6ptima de estaciones de \\ ras' en territorlo brasileno. Con una red VLBI de estaciones reales y ficti- cias simulamos observaciones. Se usan los datos generados de estps ex- perimentos para obtener Ia distribuci6n de brillo de radiofuentes fic- ticias por medlo de tecaicas de mapeo bIbrido. Se concluye que l mejor localizaci6n de estacionee'VLBI futuras, tomando en cuenta las estacio- nes de EUA y de Europa, se encuentra en el Norte-Noreste de razll. El analisis de los datos se hizo con los programas de CALTECH, los cuales estan instalados en una computadora VAX del Departamento de Astronomla del Instituto Astron6mico y Geoflsico de la Universidad de Sa"'o Paulo. ABSTRACT: In this work we study the optimum localization for future VLBI stations in the Brazilian territory. With a VLBI network of real and fictitious stations we make simulations of observations. The data generated in these experiments are used to obtain brightness distribution of a fictitious radio source by the hybrid mapping techniques. We conclude that the best localization of a future VLBI station taking into account the addition of US and European Stations, is roughly in North-Northeast sites in Brazil. The analysis of the data is made with the software of CALTECH, which is installed in the VAX computer of the Astronomy Department of Instituto e Geofisico - USP. Key `{` : INSTRUMENTS - INTERFEROMETRY

  14. Relevamiento de HI en el Hemisferio Austral

    NASA Astrophysics Data System (ADS)

    Arnal, E. M.; Bajaja, E.; Morras, R.; Pöppel, W. G. L.

    Un nuevo relevamiento de HI de todo el Hemisferio Austral, comprendido entre -90o <= δ <= -25o, está siendo observado con la antena I del IAR. El mismo es realizado con alta sensibilidad (r.m.s.<= 0.07 K) y alta resolución espectral (1 Km/s). Un total de ~50000 posiciones en el cielo serán observadas, espaciadas en una grilla (lxb) de (0.5o x 0.5o). El intervalo de velocidades cubierto en este relevamiento abarca el rango -450 km/s a +450 km/s en el sistema LSR. Esta base de datos será corregida por efectos de ``stray radiation''. Al presente se ha observado ~70% del total del relevamiento. El mismo es complementario de uno similar realizado en el Hemisferio Norte por Hartman y Burton (1996), con cubrimiento espacial, sensibilidad, resoluciones espaciales y en velocidad, similares a los del IAR. El objetivo final de ambos relevamientos es disponer de una base de datos uniforme en todo el cielo.

  15. New Curculionoidea (Coleoptera) records for Canada

    PubMed Central

    Douglas, Hume; Bouchard, Patrice; Anderson, Robert S.; de Tonnancour, Pierre; Vigneault, Robert; Webster, Reginald P.

    2013-01-01

    Abstract The following species of Curculionoidea are recorded from Canada for the first time, in ten cases also representing new records at the generic level: Ischnopterapion (Ischnopterapion) loti (Kirby, 1808); Stenopterapion meliloti (Kirby, 1808) (both Brentidae); Atrichonotus taeniatulus (Berg, 1881); Barinus cribricollis (LeConte, 1876); Caulophilus dubius (Horn, 1873); Cionus scrophulariae (Linnaeus, 1758); Cryptorhynchus tristis LeConte, 1876; Cylindrocopturus furnissi Buchanan, 1940; Cylindrocopturus quercus (Say, 1832); Desmoglyptus crenatus (LeConte, 1876); Pnigodes setosus LeConte, 1876; Pseudopentarthrum parvicollis (Casey, 1892); Sibariops confinis (LeConte, 1876); Sibariops confusus (Boheman, 1836); Smicronyx griseus LeConte, 1876; Smicronyx lineolatus Casey, 1892; Euwallacea validus (Eichhoff, 1875); Hylocurus rudis (LeConte, 1876); Lymantor alaskanus Wood, 1978; Phloeotribus scabricollis (Hopkins, 1916); Scolytus oregoni Blackman, 1934; Xyleborus celsus Eichhoff, 1868; Xyleborus ferrugineus (Fabricius, 1801); Xylosandrus crassiusculus (Motschulsky, 1866) (all Curculionidae). In addition the following species were recorded for the first time from these provinces and territories: Yukon – Dendroctonus simplex LeConte, 1868; Phloetribus piceae Swaine, 1911 (both Curculionidae); Northwest Territories – Loborhynchapion cyanitinctum (Fall, 1927) (Brentidae); Nunavut – Dendroctonus simplex LeConte, 1868 (Curculionidae); Alberta – Anthonomus tectus LeConte, 1876; Promecotarsus densus Casey, 1892; Dendroctonus ponderosae Hopkins, 1902; Hylastes macer LeConte, 1868; Rhyncolus knowltoni (Thatcher, 1940); Scolytus schevyrewi Semenov Tjan-Shansky, 1902 (all Curculionidae); Saskatchewan – Phloeotribus liminaris (Harris, 1852); Rhyncolus knowltoni (Thatcher, 1940); Scolytus schevyrewi Semenov Tjan-Shansky, 1902 (all Curculionidae); Manitoba – Cosmobaris scolopacea Germar, 1819; Listronotus maculicollis (Kirby, 1837); Listronotus punctiger LeConte, 1876

  16. Seasonal relationships between birds and arthropods in bottomland forest canopy gaps.

    SciTech Connect

    Bowen, Liessa, Thomas

    2004-12-31

    Bowen, Liessa, Thomas. 2004. Seasonal relationships between birds and arthropods in bottomland forest canopy gaps. PhD Dissertation. North Carolina State University. Raleigh, North Carolina. 98pp. I investigated the influence of arthropod availability and vegetation structure on avian habitat use at the center, edge, and adjacent to forest canopy gaps in 2001 and 2002. I used mist-netting and plot counts to estimate abundance of birds using three sizes (0.13, 0.26, and 0.5 ha) of 7-8 year old group-selection timber harvest openings during four seasons (spring migration, breeding, post-breeding, and fall migration) in a bottomland hardwood forest in the Upper Coastal Plain of South Carolina. I used foliage clipping, Malaise trapping, and pitfall trapping to determine arthropod abundance within each habitat, and I used a warm water crop-flush on captured birds to gather information about arthropods eaten. I observed more birds, including forest interior species, forest-edge spedge species, and several individual species, in early-successional canopy gap and gap-edge habitats than in surrounding mature forest during all seasons. I found a significant interaction between season and habitat type for several groups and individual species, suggesting a seasonal shift in habitat use. Captures of all birds, insectivorous birds, foliage- gleaners, ground-gleaners, aerial salliers, Hooded Warbler (Wilsonia citrina), Northern Cardinal (Cardinalis cardinalis), White-eyed Vireo (Vireo griseus), and Black-throated Blue Warbler (Dendroica caerulescens) were positively correlated with understory vegetation density during two or more seasons. I found relationships between insectivorous birds and leaf-dwelling Lepidoptera, insectivorous birds and ground-dwelling arthropods, foliage-gleaning birds and foliage-dwelling arthropods, and aerial salliers and flying arthropods, as well as between individual bird species and arthropods. Relationships were inconsistent, however, with many

  17. A prototype sensor system for the early detection of microbially linked spoilage in stored wheat grain

    NASA Astrophysics Data System (ADS)

    de Lacy Costello, B. P. J.; Ewen, R. J.; Gunson, H.; Ratcliffe, N. M.; Sivanand, P. S.; Spencer-Phillips, P. T. N.

    2003-04-01

    Sensors based on composites of metal oxides were fabricated and tested extensively under high-humidity and high-flow conditions with exposure to vapours reported to increase in the headspace of wheat grain (Triticum aestivum cv Hereward) colonized by fungi. The sensors that exhibited high sensitivity to target vapours combined with high stability were selected for inclusion into a four-sensor array prototype system. A sampling protocol aligned to parallel gas chromatography-mass spectrometry and human olfactory assessment studies was established for use with the sensor system. The sensor system was utilized to assess irradiated wheat samples that had been conditioned to 25% moisture content and inoculated with pathogens known to cause spoilage of grain in storage. These included the fungi Penicillium aurantiogriseum, Penicillium vulpinum, Penicillium verrucosum, Fusarium culmorum, Aspergillus niger, and Aspergillus flavus and the actinomycete, Streptomyces griseus. The sensor system successfully tracked the progress of the infections from a very early stage and the results were compared with human olfactory assessment panels run concurrently. A series of dilution studies were undertaken using previously infected grain mixed with sound grain, to improve the sensitivity and maximize the differentiation of the sensor system. An optimum set of conditions including incubation temperature, incubation time, sampling time, and flow rate were ascertained utilizing this method. The sensor system differentiated samples of sound grain from samples of sound grain with 1% (w/w) fungus infected grain added. Following laboratory trials, the prototype sensor system was evaluated in a commercial wheat grain intake facility. Thresholds calculated from laboratory tests were used to differentiate between sound and infected samples (classified by intake laboratory technicians) collected routinely from trucks delivering grain for use in food manufacture. All samples identified as having

  18. Thanks to 70 years of Inter American Statistical cooperation, the world’s largest integrated census microdata dissemination site www.ipums.org/international

    PubMed Central

    McCAA, ROBERT

    2014-01-01

    Seventy years of Inter American Statistical cooperation, symbolized by the 70th anniversary of Estadística, made possible the construction of IPUMS-International, the world’s largest integrated census microdata dissemination site, www.ipums.org/international. Currently, the site offers access to 238 samples totaling over 540 million person records representing 74 countries. The Americas, which account for only about one-seventh of the world’s population, amount to over one-third (36%) of the person records in the IPUMS-International database. Likewise, 35% of the citations in the IPUMS-International bibliography are for studies focused on Latin America, with about half of these analyzing a single Latin American country. This article discusses salient features of the IPUMS integration methods and system. National Statistical Institutes that have not yet entrusted 2010 census microdata to the initiative are invited to do so. Researchers and teachers are invited to use the data freely in analysis and teaching. Setenta años de cooperación estadística inter-Americana, simbolizada por el 70 aniversario de la revista Estadística, han hecho posible la construcción de IPUMS-internacional, la base en línea de microdatos censales harmonizados más grande del mundo, www.ipums.org/international. Actualmente, IPUMS proporciona acceso a 238 muestras con más de 540 millones de registros individuales de 74 países. Las Américas, que albergan una séptima parte de la población mundial, representan más de un tercio (36%) de todos los registros individuales en la base de datos IPUMS-internacional. Asimismo, el 35% de todas las referencias en la bibliografía de IPUMS son de estudios realizados sobre América Latina, la mitad de éstas basadas en un sólo país de la región. Este artículo presenta las principales características del sistema de integración y difusión de datos de IPUMS. Los Institutos Nacionales de Estadísticas que todavía no ha entregado la muestra

  19. [In Process Citation].

    PubMed

    Arroyo-Izaga, Marta; Andía Muñoz, Virginia; Demon, Geert

    2016-01-01

    Introducción: la población saharaui residente en los campamentos de Tinduf (Argelia) se considera vulnerable desde el punto de vista nutricional.Objetivos: evaluar los hábitos dietéticos de un grupo de mujeres emigrantes saharauis con el fin de obtener datos para diseñar un programa de educación nutricional (EN) destinado a mujeres residentes en los campamentos.Métodos: la información sobre hábitos dietéticos se registró a través de historias dietéticas. Los resultados de ingesta de macro y micronutrientes se compararon con los rangos aceptables de distribución y los requerimientos medios estimados. También se recogieron datos demográficos, socioeconómicos y sobre salud. Análisis estadístico: SPSS vs 22.0. A partir de los datos obtenidos y de la revisión de los programas de salud llevados a cabo en campamentos y de otros programas de EN se diseñó un programa específico.Resultados: la alimentación en campamentos se caracterizó por ser deficitaria en energía y por un bajo consumo de fibra (6,1 [2,8] g/día), de ácidos grasos monoinsaturados (6,9 [2,9]% del valor calórico total) y de la mayoría de los micronutrientes. El aumento en la disponibilidad de alimentos tras emigrar a España incrementó la ingesta calórica, pero la dieta siguió siendo inadecuada. El programa de EN diseñado se basó en la formación de formadoras. En este manuscrito se proporciona información detallada sobre la organización y el material a emplear en esta intervención educativa.Discusión y conclusión: la alimentación de las mujeres saharauis en campamentos y tras emigrar a España fue inadecuada, lo que corrobora que la aculturación puede estar asociada a cambios no saludables. Cabe esperar que el programa de EN diseñado contribuya a mejorar su bienestar nutricional. PMID:27019252

  20. Manual del espectrógrafo multifunción de Bosque Alegre

    NASA Astrophysics Data System (ADS)

    Díaz, R.; Paolantonio, S.; Carranza, G.; Goldes, G.

    Este manual consta de 120 páginas y resume las características del Espectrógrafo Multifunción instalado en el telescopio de 1.54 m de la Estación Astrofísica de Bosque Alegre. En este trabajo se describen, además, las técnicas a emplear para su puesta a punto y la secuencia de operaciones para la obtención de datos en cada uno de los modos que ya se encuentran en funcionamiento. Parte de este trabajo se realizó con el apoyo de la Asociación Argentina de Astronomía, a través de becas otorgadas a R.D. y S.P..

  1. Estudio multifrecuencia del medio interestelar cercano a HD 192281

    NASA Astrophysics Data System (ADS)

    Arnal, E. M.; Cappa, C.; Cichowolski, S.; Pineault, S.; St-Louis, N.

    Una de las causas que modifica la estructura y dinámica del medio interestelar es la acción que los vientos de las estrellas de gran masa ejercen sobre el mismo. En este trabajo, mediante el uso de datos interferométricos obtenidos en la banda de radio en la transición de 21-cm del Hidrógeno neutro y de imágenes de la emisión de continuo en las bandas de 408 y 1420 MHz, de imágenes HIRES del satélite IRAS en 60 y 100 micrones, y de observaciones de continuo obtenidas con radiotelescopios de disco simple en 2695, 4850 y 8350 MHz se ha realizado un estudio multifrecuencia de los efectos que los vientos estelares de HD 192281, una estrella de tipo espectral O5 Vn((f))p, han tenido sobre el medio interestelar que rodea a la misma.

  2. Resonancias en la región trans-neptuniana

    NASA Astrophysics Data System (ADS)

    Gallardo, T.; Ferraz-Mello, S.

    La expansión de la órbita del planeta Neptuno en la etapa de acreción del Sistema Solar exterior (Fernández e Ip 1984, 1996) parece ser un mecanismo eficiente para la captura de planetesimales en las resonancias exteriores con Neptuno (Malhotra 1995). Por otro lado, los estudios dinámicos realizados por varios autores indican que las resonancias son regiones de evolución estable, en contraste con el comportamiento caótico del resto de la región trans-neptuniana. Por estas razones, y si bien los datos observacionales son todavía muy limitados, se supone que los objetos descubiertos se encuentran en alguna de esas resonancias. En esta comunicación presentamos un estudio analítico y numérico de las principales resonancias exteriores con Neptuno.

  3. Espectro de radiación derivado de un modelo de colapso protoestelar

    NASA Astrophysics Data System (ADS)

    Coca, S.; Rohrmann, R.

    El exceso de emisión infrarroja en objetos protoestelares es atribuido usualmente a un disco de material en torno al cuerpo central. A pesar del avance alcanzado en la elaboración de modelos, aún existen dificultades para explicar la ley de temperatura del disco necesaria para reproducir las luminosidades y perfiles de energía observados. Nuestra propuesta consiste en determinar la distribución espectral de la radiación derivada de un particular modelo de colapso protoestelar, y estudiar la evolución del espectro desde estadíos tempranos de la contracción gravitatoria. Este plan es orientado a evaluar las propiedades del modelo (distribuciones de masa y temperatura del material circunestelar) por comparación con datos observacionales, a fin de inferir de ello los posibles ajustes requeridos en la teoría actualmente empleada.

  4. The type specimens of Calyptratae (Diptera) housed in non-traditional institutions in Argentina.

    PubMed

    Patitucci, Luciano Damián; Mulieri, Pablo Ricardo; Domínguez, M Cecilia; Mariluis, Juan Carlos

    2015-01-01

    The type material of species of Calyptratae Diptera belonging to Anthomyiidae, Calliphoridae, Fanniidae, Muscidae, Sarcophagidae, and Tachinidae, housed in the collections of non-traditional institutions in Argentina were examined. These collections were included in the recently created "Sistema Nacional de Datos Biológicos" (National Biological Data System). We examined four collections: "Administración Nacional de Laboratorios e Institutos de Salud 'Dr. Carlos G. Malbrán'" (ANLIS), "Instituto Nacional de Tecnología Agropecuaria, Castelar, Buenos Aires" (INTA), "Instituto Argentino de Investigaciones de las Zonas Áridas" (IADIZA); and "Fundación Félix de Azara" (CFA). Comparison of the original descriptions of these species with the label information revealed the existence of 24 holotypes, 5 lectotypes, 11 syntypes, and 441 paratypes/paralectotypes. Complete information is given for each type, including reference to the original description, label data, and preservation condition.  PMID:25661231

  5. Nuevos fenómenos en erupciones cometarias

    NASA Astrophysics Data System (ADS)

    Silva, A.

    Se discuten aquí tres procesos físicos novedosos encontrados en la actividad de cometas: 1) El rol de una distribución de granos de hielo como fuente extendida de H2O en la coma, 2) El efecto de una discontinuidad en el plasma cometario, llamada Cometopausa, sobre la excitación del radical OH , y 3) La actividad por erupciones a grandes distancias heliocéntricas (r > 5 AU). Con respecto a 1) y 2), se presentan modelos que ajustan bien con las observaciones. En cuanto a 3), se presentan explicaciones posibles al fenómeno, y se trata el interesante caso de Chirón 2060, basándose en observaciones propias tomadas desde el CASLEO y datos anteriores.

  6. Determinación de temperatura efectiva y gravedad superficial de estrellas B y A de secuencia principal

    NASA Astrophysics Data System (ADS)

    Nieva, M. F.; Pintado, O. I.; Adelman, S.; Rayle, K. E.; Sanders, S. E., Jr.

    Las temperaturas efectivas (Teff) y gravedades superficiales (log g) de un grupo de estrellas de tipo B y A de Secuencia Principal se determinaron en varias etapas. En una primera aproximación se usaron los índices fotométricos de Strömgren para realizar el cálculo con el programa de Napiwotski et al.(1993). Luego se hizo un ajuste comparando datos espectrofotométricos con flujos obtenidos con el modelo ATLAS9 en la región visible. Y a continuación se hizo un mejor ajuste comparando los perfiles de la línea Hγ con espectros sintéticos calculados con SYNTHE. Además, se analizó el efecto de usar el modelo de Canuto y Mazzitelli (1991), donde se considera The Mixing Length Theory, en modelos de atmósferas de estrellas.

  7. Nuevos sistemas de frecuencia intermedia para el IAR

    NASA Astrophysics Data System (ADS)

    Olalde, J. C.; Perilli, D.; Larrarte, J. J.

    Se presenta el diagrama en bloques de los nuevos sistemas de Frecuencia Intermedia para los dos radiómetros instalados en el IAR. Entre las características más importantes del sistema podemos mencionar la posibilidad de conectar cualquiera de las dos antenas a los ``backend" disponibles: analizador espectral de alta resolución (META II) de 0,05 Hz, autocorrelador de 1008 canales y contínuo. Se incorporan al sistema nuevos sintetizadores de frecuencia implementados con PLL y la moderna técnica de síntesis digital directa. Por último, el conjunto del sistema es susceptible de ser configurado por las computadoras de adquisición de datos, supervisadas por otra, que entrega el estado de funcionamiento actual y evita la selección de configuraciones incorrectas por parte del usuario.

  8. Informe trata el descenso del cáncer y los tumores cerebrales

    Cancer.gov

    Los índices de mortalidad en los Estados Unidos de todos los cánceres en hombres y mujeres siguieron bajando entre 2003 y 2007, que es el período más reciente del que se disponen datos, según el último Informe Anual a la Nación sobre el Estado del Cáncer. El informe encuentra también que el índice general combinado de nuevos diagnósticos de cáncer en hombres y mujeres decreció un promedio un poco menos de 1% por año en el mismo período.

  9. SDI-based business processes: A territorial analysis web information system in Spain

    NASA Astrophysics Data System (ADS)

    Béjar, Rubén; Latre, Miguel Á.; Lopez-Pellicer, Francisco J.; Nogueras-Iso, Javier; Zarazaga-Soria, F. J.; Muro-Medrano, Pedro R.

    2012-09-01

    Spatial Data Infrastructures (SDIs) provide access to geospatial data and operations through interoperable Web services. These data and operations can be chained to set up specialized geospatial business processes, and these processes can give support to different applications. End users can benefit from these applications, while experts can integrate the Web services in their own business processes and developments. This paper presents an SDI-based territorial analysis Web information system for Spain, which gives access to land cover, topography and elevation data, as well as to a number of interoperable geospatial operations by means of a Web Processing Service (WPS). Several examples illustrate how different territorial analysis business processes are supported. The system has been established by the Spanish National SDI (Infraestructura de Datos Espaciales de España, IDEE) both as an experimental platform for geoscientists and geoinformation system developers, and as a mechanism to contribute to the Spanish citizens knowledge about their territory.

  10. The Malaysian Orthopaedic Association humanitarian mission to Indonesia and Sri Lanka.

    PubMed

    Sharaf, I; Saw, A; Hyzan, Y; Sivananthan, K S

    2005-07-01

    The tsunami which occurred off the west coast of North Sumatra on December 26, 2004 devastated the coastal areas of North Sumatra, South-West Thailand, South-East India and Sri Lanka killing more than a quarter of a million people. The destruction was enormous with many coastal villages destroyed. The other countries affected were Malaysia, Myanmar, Maldives, Bangladesh, Somalia, Kenya, Tanzania and the Seychelles. In January 2005, volunteers went in weekly rotation to Banda Aceh in collaboration with Global Peace Mission. These were Dr Hyzan Yusof, Dr Suryasmi Duski, Dr Sharaf Ibrahim, Dr Saw Aik, Dr Kamariah Nor and Dr Nor Azlin. In Banda Aceh, the surgical procedures that we could do were limited to external fixation of open fractures and debriding infected wounds at the Indonesian Red Crescent field hospital. In February, a team comprising Dato Dr K S Sivananthan, Dr T Kumar and Dr S Vasan spent a week in Sri Lanka. In Sri Lanka, Dato Sivananthan and his team were able to perform elective orthopaedic operations in Dr Poonambalam Memorial Hospital. We appealed for national and international aid and received support from local hospitals and the orthopaedic industry. International aid bound for Banda Aceh arrived in Kuala Lumpur from the Philippine Orthopaedic Association, the Chiba Children's Hospital in Japan and the Chinese Orthopaedic Association. The COA donated 1.5 tons of orthopaedic equipments. A special handing over ceremony from the COA to the Indonesian Orthopaedic Association was held in Putrajaya in March. Malaysia Airlines flew in the donated equipment to Kuala Lumpur while the onward flight to Aceh was provided by the Royal Malaysian Air Force. In April, Dr Saw Aik and Dr Yong Su Mei joined the Tsu-Chi International Medical Association for volunteer services on Batam Island, Indonesia. The MOA acknowledges the many individuals and organizations, both governmental and non-governmental, for their contributions in the humanitarian efforts. PMID

  11. Programmed home visits by nursing professionals to older adults: prevention or treatment?1

    PubMed Central

    Dios-Guerra, Caridad; Carmona-Torres, Juan Manuel; Ruíz-Gándara, África; Muñoz-Alonso, Adoración; Rodríguez-Borrego, María-Aurora

    2015-01-01

    OBJETIVOS: conocer la repercusión de la visita domiciliaria de los profesionales en enfermería a personas de 65 años o más, pluripatológicas, en morbimortalidad. MÉTODO: estudio retrospectivo caso-control por auditoria de historias clínicas. Muestreo aleatorio. Variables principales morbilidad, mortalidad; descriptivas: visitas de la enfermera, filiación, datos clínicos y socio sanitarios. Análisis por medidas de tendencia central, dispersión, posición, tabulación, frecuencias relativas, absolutas; no paramétricas, contrastes χ2; Wilcoxon-Mann-Whitney. RESULTADOS: se estudiaron a 1743 pacientes, de ellos 199 recibieron visita domiciliaria; la edad media de quien recibe visita es de 81,99 años; estos presentan mayor número de patologías de media 3,76; habitan en domicilio particular, si bien en conjunto presentan más institucionalización que los controles; el 50% no tiene identificado el Cuidador Principal; es mayor el número de visitas de las enfermeras a los pacientes que viven en residencias (p < 0,001). El 50% de casos no tiene plan de cuidados, con relación significativa (p < 0,001). No existen diferencias significativas en tiempo de vida entre los casos y los controles. CONCLUSIÓN: la visita domiciliaria del profesional en enfermería no repercute en la morbimortalidad; visita a los pacientes cuando ya ha aparecido el problema de salud, no hay datos de prevención. PMID:26312638

  12. Aplicación de la metodología Molecular de Orbitales de Defecto Cuántico (MQDO) al cálculo de intensidades vibrónicas y vidas medias de niveles vibracionales

    NASA Astrophysics Data System (ADS)

    María Velasco Sanz, Ana

    Desde que se formuló, en 1996, la metodología Molecular de Orbitales de Defecto Cuántico (MQDO) [1], se han obtenido datos de calidad relativos a intensidades de bandas electrónicas que implican estados Rydberg para una gran variedad de sistemas moleculares [2]. Animados por los buenos resultados obtenidos, recientemente hemos abordado el estudio de transiciones vibrónicas, es decir aquellas que ocurren entre estados vibracionales que pertenecen a distintos estados Rydberg electrónicos. Como prototipo adecuado para nuestros propósitos hemos elegido la molécula de NO, importante en la química de la atmósfera, y para la cual existen en la bibliografía datos experimentales de calidad suficiente para contrastar la validez de nuestros resultados. En concreto, hemos calculado las fuerzas de oscilador y coeficientes de Einstein para transiciones electrónicas y vibrónicas de las principales bandas del NO, al igual que vidas medias radiativas de niveles vibracionales de dicha molécula. Las propiedades estudiadas son esenciales para la comprensión de los aspectos teóricos de los procesos físicos básicos relativos a la dispersión electrónica en moléculas heteronucleares con capas abiertas. Además, valores fiables de probabilidades de transición moleculares tienen importantes aplicaciones en Astrofísica, en la modelización de procesos fotodinámicos moleculares, etc., al igual que para evaluar más profundamente la validez de nuestra metodología teórica.

  13. Determinacion de periodos fundamentales del suelo mediante vibraciones ambientales en el municipio de Humacao, Puerto Rico

    NASA Astrophysics Data System (ADS)

    Cintron Aponte, Rommel

    La tecnica de Nakamura ha sido utilizada a nivel mundial para determinar periodos fundamentales del suelo. La tecnica consiste en calcular y graficar cocientes espectrales H/V de vibraciones ambientales registradas sobre el suelo. Mediciones de vibraciones ambientales fueron tomadas en 151 lugares dentro del municipio de Humacao, localizado al este de Puerto Rico. Los datos se procesaron utilizando espectros de Fourier y espectros de potencia. La tecnica fue validada al compararla con los resultados de cocientes espectrales H/V de registros de sismos debiles y tambien con una modelacion numerica realizada con datos de un ensayo "downhole". Las graficas de los cocientes espectrales H/V fueron divididas en casos y grupos, los cuales dependen de la facilidad para identificar el periodo fundamental pico y amplitudes en frecuencias menores de 1 Hz, respectivamente. Los resultados obtenidos con ambos espectros fueron comparados y se concluye que los mismos se complementan para proveer resultados mas confiables. Se crearon mapas de periodos fundamentales, factores de amplitud, isoperiodos y clasificacion sismica de sitio. Los mapas de isoperiodos fueron realizados en las zonas mas pobladas sobre depositos de suelo. El mapa de periodos fundamentales del suelo mostro buena correlacion con la geologia local. El mapa de clasificacion sismica derivado de periodos de sitio fue comparado con el mapa de clasificacion sismica derivado de barrenos geotecnicos. El mapa de clasificacion obtenido de periodos puede sobreestimar un poco algunas clasificaciones del suelo. Sin embargo, este mapa puede proveer un estimado aproximado de la velocidad de onda de corte promedio del suelo hasta una profundidad de 100 pies (30 metros).

  14. Obstáculos a la adherencia y retención en los sistemas de salud público y privado según pacientes y personal de salud

    PubMed Central

    Arístegui, Inés; Dorigo, Analía; Bofill, Lina; Bordatto, Alejandra; Lucas, Mar; Cabanillas, Graciela Fernández; Sued, Omar; Cahn, Pedro; Cassetti, Isabel; Weiss, Stephen; Jones., Deborah

    2016-01-01

    Resumen Introducción el Programa Nacional de Sida garantiza el acceso universal a los antirretrovirales, aun así las personas que reciben medicamentos a través del sistema público no logran obtener una carga viral indetectable en la misma proporción que los pacientes del sistema privado. Este estudio cualitativo tiene como objeto identificar los factores asociados a la adherencia y retención en la cascada de atención de VIH de los sistemas de salud público y privado de Buenos Aires, según las percepciones de pacientes y del personal de salud. Métodos se registraron datos cualitativos de 12 entrevistas semi-estructuradas a informantes clave y 4 grupos focales de pacientes y personal de salud tanto del sistema público como privado. Se codificaron y analizaron temas predeterminados sobre adherencia, utilizando el software QRS Nvivo9® de análisis de datos cualitativos. Resultados pacientes y personal de salud de ambos sistemas coinciden en la importancia del estigma asociado al VIH, la relación médicopaciente, la comunicación entre ambos y la división de responsabilidades en relación al tratamiento como aspectos fundamentales para la adherencia y retención en la cascada de atención. Se observan diferencias entre los sistemas en la forma en que algunos de estos aspectos actúan. Las barreras estructurales se presentan como principales obstáculos del sistema público. Discusión se resalta la necesidad de intervenciones focalizadas en la díada médico-paciente que considere las particularidades de cada sistema de atención para facilitar el compromiso del paciente en la adherencia. PMID:26878024

  15. El Sistema de Referencia Celeste convencional de la IAU

    NASA Astrophysics Data System (ADS)

    Arias, E. F.

    La Unión Astronómica Internacional (IAU) recomendó la adopción de un nuevo sistema de referencia celeste baricéntrico cuyo plano fundamental y origen de ascensiones rectas estén próximos, respectivamente, al ecuador y equinoccio dinámicos J2000.0. El nuevo sistema de referencia estará materializado por las posiciones J2000.0 de radiofuentes extragalácticas determinadas con la técnica de interferometría de larga línea de base (VLBI). El Working Group on Reference Frames de la IAU (WGRF) decidió adoptar (Grasse, 1995) al sistema de referencia celeste extragaláctico del Servicio Internacional de la Rotación Terrestre (IERS) como futuro sistema de referencia celeste convencional bajo el nombre International Celestial Reference System (ICRS) y encomendó su mantenimiento futuro al IERS. El marco de referencia que materializará al ICRS contiene posiciones precisas J2000.0 de más de 600 radiofuentes extragalácticas. Las coordenadas fueron ajustadas en una única solución VLBI en la cual se incluyeron todas las observaciones realizadas hasta octubre de 1995 con la técnica de adquisición de datos VLBI Mark III. Para minimizar los errores sistemáticos que pueden afectar la calidad del marco de referencia se introdujeron mejoras sustanciales en la modelización y en la selección de datos. Un subconjunto de objetos del marco de referencia se utilizó para referir las posiciones estelares determinadas con el satélite astrométrico Hipparcos al ICRS.

  16. Herbarium of the University of Malaga (Spain): Vascular Plants Collection

    PubMed Central

    García-Sánchez, José; Cabezudo, Baltasar

    2013-01-01

    la colección principal del herbario. La base de datos MGC-Cormof tiene como objetivo la digitalización y publicación de los datos asociados con los más de 76.000 ejemplares depositados en la colección, de los cuales el 97,2% de las muestras se encuentran identificadas a nivel de especie. Desde 2011, los Servicios Centrales de Investigación (SCAI) de la Universidad de Málaga son responsables de mantener el herbario y sus respectivas bases de datos. Esta colección está en continuo crecimiento, con una incorporación anual de unos 1.500 ejemplares. Casi el 96% de la colección está digitalizada, a través del programa Herbar v3.7.1 (F. Pando et al. 1996–2011) por lo que más de 73.000 especímenes son accesibles a través de la red de GBIF (http://data.gbif.org/datasets/resource/8105/). Actualmente, la colección MGC-Cormof está constituida por 247 familias y 8.110 taxones, distribuidos en angiospermas (93,97%), helechos y plantas afines (4,89%) y gimnospermas (1,14%). Las familias y géneros mejor representados en la colección son Compositae, Leguminosae, Gramineae, Labiatae, Caryophyllaceae, Teucrium, Silene, Asplenium, Linaria y Quercus. La mayoría de los especímenes provienen de la región del Mediterráneo Occidental, fundamentalmente del sur de España (Andalucía: 82% de las muestras) y del norte de Marruecos (2,17%). Aproximadamente, el 63% de las muestras se encuentran georreferenciadas. La identificación de los ejemplares de la colección ha sido realizada por personal del departamento de biología vegetal de la Universidad de Málaga y además un 40% de los ejemplares ha sido revisado por especialistas. La base de datos MGC-Cormof ha sido revisada mediante la herramienta DarwinTest v3.2 (Ortega-Maqueda and Pando 2008) antes de ser publicada en GBIF. Los datos incluidos en esta base de datos son importantes para trabajos de conservación, taxonomía, flora, cartografía, fenología, palinología, entre otros. PMID:24194668

  17. GIS-based hydrogeological databases and groundwater modelling

    NASA Astrophysics Data System (ADS)

    Gogu, Radu Constantin; Carabin, Guy; Hallet, Vincent; Peters, Valerie; Dassargues, Alain

    2001-12-01

    'applications qui ont été développées permet dès maintenant de prochaines avancées. L'intérêt grandit pour le potentiel d'intégration de la technologie des SIG et les modèles de simulation des nappes. Un outil de couplage a été créé entre le schéma de base de données spatiales et l'interface GMS (GroundWater Modelling System, système de modélisation de nappe) du modèle numérique de nappe. Suivant les requêtes en fonction du temps et de l'espace, les données hydrogéologiques stockées dans la base de données peuvent être aisément utilisées dans différents modèles numériques de nappes. Resumen. La fiabilidad y validez de los análisis de aguas subterráneas dependen enormemente de la disponibilidad de muchos datos de alta calidad. Integrarlos en una estructura consistente y lógica mediante un entorno informático sirve para asegurar su validez y disponibilidad, y rrepresenta una herramienta muy potente para ulteriores estudios hidrogeológicos. Se ha diseñado en la región de Valonia (Bélgica) una base de datos hidrogeológica basada en un sistema de información geográfica (GIS), con el que se dispone de útiles para elaborar análisis de vulnerabilidad y modelos hidregeológicos. Se ha utilizado datos de cinco cuencas fluviales, elegidas por sus características hidrogeológicas contrastadas, así como un conjunto de aplicaciones desarrolladas con vistas al futuro. El interés por el potencial que ofrece la integración de la tecnología GIS y los modelos de simulación de aguas subterráneas está en auge. Se ha desarrollado un "emulador" que integra el esquema espacial de la base de datos y la interfaz GMS (GroundWater Modelling System) de modelación numérica de aguas subterráneas. A partir de búsquedas temporales y espaciales, los datos hidrogeológicos almacenados en la base de datos pueden ser utilizados fácilmente en modelos numéricos diferentes de aguas subterráneas.

  18. Herbarium of the university of malaga (Spain): vascular plants collection.

    PubMed

    García-Sánchez, José; Cabezudo, Baltasar

    2013-01-01

    ón principal del herbario. La base de datos MGC-Cormof tiene como objetivo la digitalización y publicación de los datos asociados con los más de 76.000 ejemplares depositados en la colección, de los cuales el 97,2% de las muestras se encuentran identificadas a nivel de especie. Desde 2011, los Servicios Centrales de Investigación (SCAI) de la Universidad de Málaga son responsables de mantener el herbario y sus respectivas bases de datos. Esta colección está en continuo crecimiento, con una incorporación anual de unos 1.500 ejemplares. Casi el 96% de la colección está digitalizada, a través del programa Herbar v3.7.1 (F. Pando et al. 1996-2011) por lo que más de 73.000 especímenes son accesibles a través de la red de GBIF (http://data.gbif.org/datasets/resource/8105/). Actualmente, la colección MGC-Cormof está constituida por 247 familias y 8.110 taxones, distribuidos en angiospermas (93,97%), helechos y plantas afines (4,89%) y gimnospermas (1,14%). Las familias y géneros mejor representados en la colección son Compositae, Leguminosae, Gramineae, Labiatae, Caryophyllaceae, Teucrium, Silene, Asplenium, Linaria y Quercus. La mayoría de los especímenes provienen de la región del Mediterráneo Occidental, fundamentalmente del sur de España (Andalucía: 82% de las muestras) y del norte de Marruecos (2,17%). Aproximadamente, el 63% de las muestras se encuentran georreferenciadas. La identificación de los ejemplares de la colección ha sido realizada por personal del departamento de biología vegetal de la Universidad de Málaga y además un 40% de los ejemplares ha sido revisado por especialistas. La base de datos MGC-Cormof ha sido revisada mediante la herramienta DarwinTest v3.2 (Ortega-Maqueda and Pando 2008) antes de ser publicada en GBIF. Los datos incluidos en esta base de datos son importantes para trabajos de conservación, taxonomía, flora, cartografía, fenología, palinología, entre otros. PMID:24194668

  19. Hydrochemical tracers in the middle Rio Grande Basin, USA: 2. Calibration of a groundwater-flow model

    NASA Astrophysics Data System (ADS)

    Sanford, Ward E.; Plummer, L. Niel; McAda, Douglas P.; Bexfield, Laura M.; Anderholm, Scott K.

    té construit avec les logiciels MODFLOW, MODPATH et UCODE, et calibré en utilisant les concentrations en 14C et la position de certaines zones définies par les données hydrochimiques. L'estimation de certains paramètres a été réalisée en utilisant une combinaison de techniques de régression non linéaire et une méthode de recherche exhaustive (Brute Force Search) de l'erreur minimum entre les résultats des observations et les simulations. Les valeurs de la recharge calibrée sont substantiellement plus basses que celles estimées dans les modèles antérieurs. Les résultats d'une simulation en régime transitoire sur 30.000 ans suggèrent que la recharge au maximum de la dernière glaciation (last glacial maximum, LGM) était 10 fois supérieure au taux actuel, mais que la recharge qui a suivit la LGM était plus bas que la recharge actuelle. La calibración de un modelo de aguas subterráneas con el apoyo de datos hidroquímicos ha demostrado que la recarga relativamente baja en la cuenca media del Río Grande es probablemente responsable de una depresión de aguas subterráneas en el centro de la cuenca y de la presencia de una cantidad considerable de agua del Río Grande en el acuífero del Grupo Santa Fe. Los modelos propuestos con anterioridad para la cuenca tenían dificultades para reproducir estas características ya que no tenían datos hidroquímicos que permitieran delimitar los ritmos y distribución de recarga. El objetivo del presente estudio consistió en utilizar una gran cantidad de datos hidroquímicos disponibles para ayudar a calibrar los parámetros del modelo, incluyendo los ritmos de recarga. El modelo se construyó utilizando los modelos MODFLOW, MODPATH, y UCODE del USGS, mientras que la calibración se realizó en base a concentraciones de 14C y a la posición de ciertas zonas definidas con los datos hidroquímicos. La estimación de parámetros se realizó en base a una combinación de técnicas de regresiones no lineares y a una b

  20. Regional characterisation of hydraulic properties of rock using air-lift data

    NASA Astrophysics Data System (ADS)

    Wladis, David; Gustafson, Gunnar

    les données disponibles présentent une certaine imprécision. Au départ, il faut cependant examiner l'utilité potentielle, c'est-à-dire la précision attendue, de données imprécises dans chaque cas spécifique. Cette étude analyse les possibilités d'obtenir des estimations de transmissivitéà partir de données d'air-lift dans des roches de socle en Suède, au mieux à un facteur 10 près par rapport aux données d'excellente qualité fournies par des essais d'injection. La précision attendue des résultats a été examinée analytiquement et grâce à des méthodes statistiques. Les résultats ont aussi été comparés aux données d'essais d'injection. Les résultats indiquent que les données obtenues par air-lift fournissent des estimations de transmissivitéà un facteur 10 près par comparaison avec celles des essais d'injection des exemples étudiés. L'étude montre aussi que la pénétration partielle et la fracturation hydraulique peuvent affecter les estimations seulement d'environ un facteur 5. Ainsi, le recours à des données existantes peut être économiquement plus intéressant que le recueil de nouvelles données dans les premières étapes des études hydrogéologiques. Resumen Los estudios hidrogeológicos, en general, y las estimaciones de propiedades hidráulicas en rocas, en particular, requieren gran cantidad de datos. En muchos países se han creado grandes bases de datos hidrogeológicos, recogidos y almacenados a lo largo de los años. Por tanto, el uso de los datos ya existentes, aunque imprecisos, puede suponer una alternativa barata a la recopilación de nuevos datos, particularmente en las primeras fases de un estudio hidrogeológico. Sin embargo la precisión y utilidad del método deben analizarse para cada caso específico. En este estudio se contempla la posibilidad de, a partir de datos de ensayos de inyección de aire realizados en Suecia, obtener valores estimativos de transmisividad dentro del orden de magnitud de los

  1. Hydrochemical tracers in the middle Rio Grande Basin, USA: 2. Calibration of a groundwater-flow model

    NASA Astrophysics Data System (ADS)

    Sanford, Ward E.; Plummer, L. Niel; McAda, Douglas P.; Bexfield, Laura M.; Anderholm, Scott K.

    té construit avec les logiciels MODFLOW, MODPATH et UCODE, et calibré en utilisant les concentrations en 14C et la position de certaines zones définies par les données hydrochimiques. L'estimation de certains paramètres a été réalisée en utilisant une combinaison de techniques de régression non linéaire et une méthode de recherche exhaustive (Brute Force Search) de l'erreur minimum entre les résultats des observations et les simulations. Les valeurs de la recharge calibrée sont substantiellement plus basses que celles estimées dans les modèles antérieurs. Les résultats d'une simulation en régime transitoire sur 30.000 ans suggèrent que la recharge au maximum de la dernière glaciation (last glacial maximum, LGM) était 10 fois supérieure au taux actuel, mais que la recharge qui a suivit la LGM était plus bas que la recharge actuelle. La calibración de un modelo de aguas subterráneas con el apoyo de datos hidroquímicos ha demostrado que la recarga relativamente baja en la cuenca media del Río Grande es probablemente responsable de una depresión de aguas subterráneas en el centro de la cuenca y de la presencia de una cantidad considerable de agua del Río Grande en el acuífero del Grupo Santa Fe. Los modelos propuestos con anterioridad para la cuenca tenían dificultades para reproducir estas características ya que no tenían datos hidroquímicos que permitieran delimitar los ritmos y distribución de recarga. El objetivo del presente estudio consistió en utilizar una gran cantidad de datos hidroquímicos disponibles para ayudar a calibrar los parámetros del modelo, incluyendo los ritmos de recarga. El modelo se construyó utilizando los modelos MODFLOW, MODPATH, y UCODE del USGS, mientras que la calibración se realizó en base a concentraciones de 14C y a la posición de ciertas zonas definidas con los datos hidroquímicos. La estimación de parámetros se realizó en base a una combinación de técnicas de regresiones no lineares y a una b

  2. Operational tools and applications of EO satellite data to retrieve surface fluxes in semi-arid countries

    NASA Astrophysics Data System (ADS)

    Tanguy, Maliko

    ítulo 4), se evalúa la fiabilidad de una nueva parametrización para estimar el flujo de calor en el suelo (G) con el fin de ser utilizado en métodos de estimación de la evapotranspiración (ET) usando datos de teledetección. La parametrización de G se optimiza usando datos de flujo de energía obtenido durante las campañas del proyecto AMMA, y muestra buenos resultados y una mejora de las estimaciones del flujo de calor sensible (H) y de ET cuando se utiliza conjuntamente con el método del triángulo (Jiang & Islam, 2001). En una segunda parte (Capítulo 5), el método del triángulo se compara con valores de ET estimado por un modelo de superficie terrestre (JULES). Se intenta calibrar JULES usando el método del triángulo mediante simulaciones de Monte Carlo, pero los dos métodos muestran resultados muy diferentes, indicando que se necesita tareas de comparación profundizadas para poder evaluar la eficacia de estos modelos (de superficie terrestre y basados en la teledetección) para estimar los flujos de energía a la superficie. El capítulo 6 presenta un conjunto de ejemplos de aplicaciones operacionales para estimar los flujos de superficie usando datos de teledetección. El primer ejemplo consiste en el estudio de la evolución temporal de mapas de ET en África occidental bajo la influencia del monzón africano. En el segundo ejemplo, se aplica la nueva parametrización de G descrita en el capítulo 4 para calcular y analizar la evolución a largo plazo (2000-2009) de los componentes del balance de energía a la superficie, G, H y ET, en diferentes puntos de la cuenca del río Segura (Sureste español) utilizando datos del sensor MODIS-Terra (temperatura superficial y NDVI). La distribución temporal y espacial de ET revela diferentes controles sobre ET. En el último ejemplo, datos de temperatura superficial del mar del sensor MODIS-Aqua se utilizaron para validar un modelo matemático para calcular los flujos superficiales de una laguna costera del

  3. [In Process Citation].

    PubMed

    Moreno Rojas, Rafael; Moreno Ortega, Alicia; Medina Canalejo, Luis M; Vioque Amor, Montserrat; Cámara Martos, Fernando

    2016-01-01

    Introducción: el salmorejo cordobés está tomando fama a nivel nacional y reconocimiento internacional. Sin embargo, son muy diversas las formas de elaborarlo y, por tanto, las propiedades organolépticas y nutricionales del plato.Material y métodos: con la intención de realizar una estandarización del salmorejo y forma de elaboración que permita una posterior protección de su identidad, así como su caracterización nutricional, se ha realizado una encuesta sobre el 83% de los establecimientos de restauración de Córdoba (excluidos barrios periféricos y zona industrial) para indagar su forma de elaborarlo, en cuanto a denominación, ingredientes, preparación, precio, etc., mediante una encuesta administrada personalmente con 55 preguntas en 6 apartados.Resultado: el resultado ha sido que sólo un 21% de los establecimientos utiliza la denominación "salmorejo cordobés". Los ingredientes usados de forma sistemática se ajustan estadísticamente a una propuesta previa de sistematización y valoración nutricional, basada en datos bibliográficos y difundida en más de 50 idiomas, que corresponde a: 1.000 g de tomate, 200 g de pan de telera, 100 g de aceite de oliva virgen extra, 5 g de ajo de Montalbán y 10 g de sal. Esto corresponde por 100 g de producto a 117,4 kcal, 1,8 g de proteínas, 8,1 g de lípidos, 9,9 g de carbohidratos, 1,2 g de fibra y 380,7 mg de sodio. Como ingredientes extra minoritariamente se usa el vinagre (18% de las encuestas) y como guarnición de forma mayoritaria, taquitos de jamón y huevo duro, en tanto que algo más de un 25% añade un chorro de aceite sobre el producto terminado. Se elabora principalmente mediante vaso batidor o Termomix, siendo la receta usada de forma mayoritaria de origen familiar. Si bien se ha considerado tradicionalmente un plato estival, un 78% de establecimientos lo tienen todo el año. El 94% de los establecimientos lo consideran entre los diez platos más consumidos, y para el 18% es el m

  4. Linking Indices for Biodiversity Monitoring to Extinction Risk Theory

    PubMed Central

    Mccarthy, Michael A; Moore, Alana L; Krauss, Jochen; Morgan, John W; Clements, Christopher F

    2014-01-01

    Biodiversity indices often combine data from different species when used in monitoring programs. Heuristic properties can suggest preferred indices, but we lack objective ways to discriminate between indices with similar heuristics. Biodiversity indices can be evaluated by determining how well they reflect management objectives that a monitoring program aims to support. For example, the Convention on Biological Diversity requires reporting about extinction rates, so simple indices that reflect extinction risk would be valuable. We developed 3 biodiversity indices that are based on simple models of population viability that relate extinction risk to abundance. We based the first index on the geometric mean abundance of species and the second on a more general power mean. In a third index, we integrated the geometric mean abundance and trend. These indices require the same data as previous indices, but they also relate directly to extinction risk. Field data for butterflies and woodland plants and experimental studies of protozoan communities show that the indices correlate with local extinction rates. Applying the index based on the geometric mean to global data on changes in avian abundance suggested that the average extinction probability of birds has increased approximately 1% from 1970 to 2009. Conectando Índices para el Monitoreo de la Biodiversidad con la Teoría de Riesgo de Extinción Resumen Los índices de biodiversidad combinan frecuentemente los datos de diferentes especies cuando se usan en los programas de monitoreo. Las propiedades heurísticas pueden sugerir índices preferidos, pero carecemos de medios objetivos para discriminar a los índices con propiedades heurísticas similares. Los índices de biodiversidad pueden evaluarse al determinar qué tan bien reflejan los objetivos de manejo que un programa de monitoreo busca apoyar. Por ejemplo, la Convención sobre la Diversidad Biológica requiere reportar las tasas de extinción, así que los

  5. Pacific Continental Shelf Environmental Assessment (PaCSEA): aerial seabird and marine mammal surveys off northern California, Oregon, and Washington, 2011-2012

    USGS Publications Warehouse

    Adams, Josh; Felis, Jonathan J.; Mason, John W.; Takekawa, John Y.

    2014-01-01

    counted (19,033) with Common Murres (Uria aalge) representing the majority of individuals counted (70.4% of total). The remaining six most abundant taxa included: Surf/White-winged Scoters (Melanitta perspicillata/M. fusca; 4.8% of total), Herring/Thayer’s Gulls (Larus argentatus/L. thayeri; 3.8% of total), Cassin’s Auklets (Ptychoramphus aleuticus; 3.8% of total), Glaucous-winged Gulls (Larus glaucescens; 3.7% of total), Black-legged Kittiwakes (Rissa tridactyla; 2.0% of total), and Western Gulls (Larus occidentalis; 1.9% of total). During summer, five species comprised >95% of the total number of birds counted (17,063) with the majority comprised of Common Murres (54.1% of total) and Sooty Shearwaters (Puffinus griseus; 34.4% of total). The remaining most abundant three taxa included: Fork-tailed Storm-Petrels (Oceanodroma furcata; 3.3% of total), Western Gulls (2.1% of total), and Leach’s Storm-Petrels (Oceanodroma leucorhoa; 1.1% of total). During fall, nine species comprised >85% of the total number of birds counted (23,376) with the majority comprised of Common Murres (50.0% of total) and Sooty Shearwaters (10.5% of total). The remaining seven taxa included Cassin’s Auklets (5.2% of total), Surf/White-winged Scoters (5.1% of total), Fork-tailed Storm-Petrels (3.8% of total), Red/Red-necked Phalaropes (Phalaropus fulicarius/P. lobatus; 3.2% of total), California Gulls (Larus californicus; 3.1% of total), Northern Fulmars (Fulmarus glacialis; 2.7% of total), and Sabine’s Gulls (Xema sabini; 2.2% of total). Throughout the entire PaCSEA survey area, average densities (± SE) at sea for all marine birds combined were similar between fall (23.7 ± 1.9 birds km-2) and winter (24.0 ± 1.9 birds km-2) and least during summer (16.3 ± 2.2 birds km-2). Marine bird densities at sea varied according to bathymetric domain and season. Throughout the entire PaCSEA study area average densities (± SE) for all marine birds combined were greatest over the inner-shelf domain

  6. [Not Available].

    PubMed

    De Arriba Muñoz, Antonio; López Úbeda, Marta; Rueda Caballero, Carmen; Labarta Aizpún, José Ignacio; Ferrández Longás, Ángel

    2016-01-01

    Introducción: saber diagnosticar y tratar la obesidad se ha convertido en el mayor reto del siglo XXI, debido al aumento de su prevalencia.Objetivos: determinar los valores de normalidad de perímetro abdominal (PA) e índice de masa corporal (IMC) según edad y sexo en población española sana.Métodos: estudio longitudinal observacional realizado entre 1980 y 2014. Se incluyeron 165 niños y 169 niñas recién nacidas, recogiendo datos de forma anual hasta los 18 años (74 varones y 92 mujeres), y posteriormente a los 28 años (42 varones y 45 mujeres). Se realizó medición de peso, longitud/talla y perímetro abdominal. Se calcularon los percentiles (P3, P10, P25, P50, P75, P90, P97) de IMC y PA según edad y sexo.Resultados: se presentan datos evolutivos de IMC y PA durante la infancia, destacando cómo aumentan los valores entre los 18 y 28 años de los percentiles superiores al p50, sobre todo en mujeres. Existe una correlación positiva en relación al PA entre el valor obtenido a los 3 años con el valor de los 18 años y de los 28 años tanto en varones (r = 0,722 y r = 0,605, p = 0,000, respectivamente) como en mujeres(r = 0,922, r = 0,857, p = 0,000, respectivamente). Y entre los 18 y 28 años (r = 0,731, p = 0,000 para varones y r = 0,961, p = 0,000 para mujeres).Conclusión: se presentan valores de normalidad de PA e IMC según edad y sexo, que podrán utilizarse como herramienta de referencia para identificar a personas con riesgo de desarrollar enfermedades cardiovasculares o diabetes. PMID:27571663

  7. Evolución Dinámica de Cúmulos Estelares Abiertos

    NASA Astrophysics Data System (ADS)

    de La Fuente Marcos, R.

    Las estrellas que observamos no se formaron aisladamente, sino que lo hicieron en grupos o cúmulos. Estos sistemas estelares recibenel nombre de cúmulos estelares abiertos o galácticos cuando están constituidos por estrellas de la Población I. Los cúmulos abiertos se localizan preferentemente en el plano galáctico, y en muchos de ellos está teniendo lugar aún una activa formación estelar. El propósito principal de esta tesis doctoral es el estudio de la evolución dinámica de estos sistemas estelares por medio de simulaciones numéricas y de la comparación de sus resultados con datos observacionales. Con este fin se analizan los efectos que, sobre la dinámica de los cúmulos, ejercen varios fenómenos de interés astrofísico tales como el campo gravitatorio galáctico, la pérdida de masa causada por la evolución estelar y la presencia de binarias primordiales. En este trabajo se presentan los resultados de más de un centenar de modelos de cúmulos, con poblaciones comprendidas en el intervalo [100, 10.000] estrellas, calculados con NBODY5, un programa estándar en el campo de la Dinámica Estelar Experimental. De los mismos se deduce que el mecanismo principal que rige la dinámica de los cúmulos abiertos es la evolución estelar de su distribución de masas, encontrándose un comportamiento diferencial fuertemente dependiente de la población inicial del cúmulo. Los mecanismos responsables de la desintegración de los cúmulos abiertos son analizados en detalle, proponiéndose un modelo analítico que ajusta razonablemente los resultados de las simulaciones. Además, y con el fin de explicar el elevado número de sistemas múltiples observados en cúmulos abiertos, se estudian los efectos que, sobre los mismos, ejerce la presencia de una cierta fracción de binarias primordiales. El papel de las binarias tambiín depende de la riqueza del cúmulo y sus efectos se interrelacionan con aquellos debidos a la evolución estelar. Por último, se

  8. [In Process Citation].

    PubMed

    Álvarez-Altamirano, Karolina; Mendoza-Hernández, Alma Nubia; Carcoba-Tenorio, Carolina; García-García, José Antonio; Fuchs-Tarlovsky, Vanessa

    2016-01-01

    Introducción y objetivos: la terapia con antioxidantes durante la quimioterapia y radioterapia en pacientes con cáncer cervicouterino es controvertida. Mientras existe evidencia que sugiere que el uso de antioxidantes disminuye los efectos secundarios propios del tratamiento contra el cáncer, hay datos que sugieren que los antioxidantes incrementan el riesgo de recurrencia de cáncer por la afectación de la terapia de los tratamientos. Métodos: se dirigió un estudio clínico controlado en pacientes con cáncer cervicouterino que fueron suplementados con una mezcla de antioxidantes o placebo, con seguimiento por 4 años posteriores al término de su tratamiento antineoplásico para evaluar el efecto de los antioxidantes en la recurrencia. Tomamos datos de niveles de hemoglobina y albúmina. Se analizaron las diferencias entre grupos con la prueba de Chi-cuadrado, la sobrevida se calculó con un análisis multivariado por medio de regresión de COX. Resultados: se dio seguimiento a 103 pacientes con cáncer cervicouterino en etapa clínica IIB y IIIB de los cuales 48% fueron tratados con suplementación de antioxidantes y el 52% con placebo, originalmente y de estos se dio seguimiento a 88 pacientes durante 4 años. El 23,9% de los pacientes tratados presentaron recurrencia por cáncer mientras que el 76,1% no la presentó. El 21,6% de los pacientes presentaron metástasis, el 8% de los pacientes perteneció al grupo de antioxidantes y el 15,9% al grupo placebo (p > 0,05). Implicaciones para los pacientes supervivientes: la suplementación con antioxidantes aparentemente no interfiere con la recurrencia por cáncer, sin embargo no hay evidencia suficiente para probarlo. Posiblemente una dosis distinta sea la clave para un mejor efecto, pero serán necesarios futuros estudios que prueben efectos sobre otro tipo de dosis. Conclusiones: la suplementación con antioxidantes durante el tratamiento de pacientes con cáncer cervicouterino no tiene efectos en la

  9. [In Process Citation].

    PubMed

    Petter da Silva, Fhaira; Beatriz Dallepiane, Loiva; Ramos Kirsten, Vanessa; Maria Kirchner, Rosane

    2016-01-01

    Introducción: la esperanza de vida está aumentando y convirtiéndose en un fenómeno característico de los países desarrollados y, cada vez más, de los países en desarrollo, como Brasil. El proceso de envejecimiento produce cambios en algunas funciones fisiológicas, como la pérdida del olfato o gusto o pérdida de apetito, entre otros, que terminan alterando la ingesta de alimentos de estos individuos.Objetivos: este estudio tuvo como objetivo evaluar el consumo de alimentos de los ancianos y de los ancianos más longevos en una ciudad del sur de Brasil.Métodos: un estudio transversal realizado mediante visitas a domicilio en Palmeira das Missões - RS, Brasil. Los datos sociodemográficos, antropométricos y dietéticos fueron recogidos a través de cuestionarios y recordatorio de 24 horas. La adecuación de nutrientes se evaluó de acuerdo con las ingestas de referencia en la dieta. Los datos fueron analizados utilizando el software SPSS 18.0.Resultados: el estudio incluyó a 424 adultos mayores, el 84.4% (n = 358) de ellos menores de 80 años y el 15.6% (n = 66) con más de 80 años. La ingesta de energía y proteínas fue insuficiente tanto para jóvenes adultos como para los más ancianos. El consumo de vitaminas y minerales ha sido insuficiente en todos los adultos mayores a excepción del hierro, que presentaba una ingesta excesiva. Hubo una diferencia estadísticamente significativa entre las personas de edad y mayores sólo en cuanto al consumo de lípidos y vitamina B12. Conclusión: la mayoría de los estudios con personas mayores corrobora los resultados obtenidos en este artículo. Una ingesta inadecuada de nutrientes puede dar lugar a deficiencias nutricionales y, por lo tanto, a cambios fisiológicos y patológicos que pondrían en peligro la capacidad funcional de los ancianos. El consumo de energía y de macronutrientes resultó insuficiente tanto para los ancianos como para los ancianos más longevos. Además, el consumo de vitaminas y

  10. Las ideologias, las ciencias naturales y sus implicaciones en la educacion cientifica

    NASA Astrophysics Data System (ADS)

    Lozada Roldan, Sandra

    Este estudio ausculto las concepciones epistemologicas de los docentes de ciencia del nivel secundario con relacion a las ideologias y las ciencias naturales. Tambien examino las posiciones de los docentes ante asuntos publicos relacionados a la ciencia. Para propositos de este estudio se diseno y se valido el cuestionario con el cual se obtuvieron los resultados. La investigacion es de tipo cuantitativa y se utilizo como diseno la encuesta. El cuestionario se administro en varias actividades de desarrollo profesional para maestros de ciencia. Un total de 78 maestros del nivel secundario respondieron el cuestionario. Para analizar los datos obtenidos se utilizaron estadisticas descriptivas como la distribucion de frecuencia y el porciento. Ademas se establecieron codigos y categorias para describir las posiciones de los maestros ante asuntos publicos relacionados a la ciencia. Los analisis demostraron que entre los docentes participantes de este estudio prevalecen ciertas concepciones epistemologicas adecuadas acerca de las ciencias naturales, a la luz de la literatura consultada. Entre estas concepciones se destacan las siguientes: a) la filosofia materialista de las ciencias naturales, b) la naturaleza tentativa y constructivista del conocimiento cientifico, c) el uso de una metodologia que garantiza cierto grado de objetividad y con el que se justifican y validan los enunciados cientificos y d) la funcion instrumental del conocimiento cientifico. Sin embargo, entre los docentes participantes de este estudio prevalecen ciertas concepciones epistemologicas erroneas acerca de las ciencias naturales, a la luz de la literatura consultada. Entre estas concepciones se destacan las siguientes: a) tendencia inductivista en el que las teorias cientificas comienzan con observaciones que establecen generalizaciones, b) secuencia jerarquica de la metodologia cientifica. Ademas, entre los docentes participantes de este estudio prevalecen concepciones epistemologicas adecuadas

  11. Estudio comparativo de las moléculas isovalentes de interés atmosférico CF3Cl y CF3Br y sus correspondientes halógenos aislados Cl y Br.

    NASA Astrophysics Data System (ADS)

    Mayor, E.; Velasco, A. M.; Martín, I.; Lavín, C.

    Los estados Rydberg moleculares han suscitado en los últimos años un creciente interés entre los espectroscopistas experimentales, motivado en parte por el desarrollo de nuevas técnicas espectroscópicas capaces de investigar estos estados altamente excitados electrónicamente. Los procesos de fotoabsorción que implican estados Rydberg en los derivados halogenados del metano son de gran importancia, debido a su abundancia en la atmósfera y a sus implicaciones medioambientales. Por ello, la obtención de datos relativos a sus fuerzas de oscilador es de gran interés. En este trabajo se aborda el estudio de dichas propiedades para las moléculas isovalentes CF3Cl y CF3Br. Ambas moléculas presentan idéntica estructura electrónica para el estado fundamental por lo que se espera que sus espectros Rydberg presenten grandes similitudes, en ausencia de perturbaciones. Por ello y dada la escasez de datos relativos a fuerzas de oscilador, hemos establecido la corrección de nuestros resultados en base a las analogías esperadas en las intensidades espectrales correspondientes a transiciones análogas. Por otro lado, Novak y col. [1] han encontrado experimentalmente un marcado carácter atómico en el espectro correspondiente a estas moléculas, siendo muy similar a los de los átomos de Cl y Br. Por ello en el presente trabajo, además de establecer la comparación entre ambas moléculas hemos buscado las similitudes con sus respectivos halógenos. Los cálculos relativos a las especies moleculares se han realizado utilizando la Metodología Molécular de Orbítales de Defecto Cuántico (MQDO) [2], mientras que para el estudio de los átomos de Cl y Br se empleó la versión relativista del método (RQDO) [3].

  12. [Not Available].

    PubMed

    Santaliestra-Pasías, Alba M; Bel-Serrat, Silvia; Moreno, Luis A; Bueno, Gloria

    2016-01-01

    Introducción: la elevada prevalencia de obesidad en niños es un problema de salud global y conlleva el desarrollo de comorbilidades asociadas, como hipertensión, dislipemia, inflamación crónica e hiperinsulinemia, que a su vez son reconocidos factores de riesgo cardiovascular. Algunos estudios han observado que el consumo de productos lácteos podría ejercer un papel protector sobre el desarrollo de enfermedades cardiovasculares; sin embargo, la evidencia científica es bastante limitada en niños y adolescentes.Objetivos: investigar la relación entre el consumo de productos lácteos y factores de riesgo cardiovascular en poblaciones jóvenes.Material y métodos: se ha revisado la literatura reciente, incluyendo adicionalmente datos procedentes del estudio HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence). Se incluyó una muestra de adolescentes (12,5-17,5 años) provenientes de 8 ciudades europeas.Resultados: datos estadounidenses muestran una disminución en la frecuencia de consumo de leche, así como en el tamaño de la porción consumida. En el estudio HELENA los productos lácteos fueron el grupo de alimentos que mejor identificó a los adolescentes con bajo riesgo cardiovascular. Además, un consumo elevado de leche y yogur, así como de bebidas a base de leche y yogur, se asoció con niveles más bajos de grasa corporal, menor riesgo cardiovascular y mayor condición física cardiorrespiratoria.Conclusiones: son necesarios más estudios para proporcionar evidencia y comprender mejor los mecanismos subyacentes de la asociación entre la ingesta de lácteos, especialmente el yogur, y la obesidad, la diabetes, y otros factores de riesgo cardiovascular. PMID:27571861

  13. El rol de Ia colaboracion y el Modelo de Aprendizaje Basado en Proyectos (ABPr) mediante el lente de la Teoria de Actividad (CHAT): un estudio de caso con estudiantes de 9no grado

    NASA Astrophysics Data System (ADS)

    Delgado, Isabel C.

    Los modelos de eensenanza y aprendizaje constructivistas conceptualizan el aprendizaje como un proceso activo. El modelo de Aprendizaje Basado en Proyectos (ABPr) se distingue por una serie de componentes, entre los cuales se destaca el aspecto colaborativo y cooperativo como un reto al momento de su implantacion. Son pocas las investigaciones que se concentran en este aspecto del modelo. En este estudio, se analizaron las diversas interacciones que surgen durante la implantacion de una unidad curricular sobre el tema de Geologia de Puerto Rico, la cual se diseno con el modelo ABPr cuyo enfoque es orientacion a proyectos. Particularmente, se examinaron las interacciones sociales que surgen entre los pares y entre pares y docente durante el proceso de planificacion y desarrollo de los productos finales, al igual que las interacciones entre los estudiantes y el material didactico en estas etapas del modelo. La investigacion es de tipo cualitativo e incorpora como diseno el estudio de caso. Las diversas interacciones constituyen la unidad de analisis. En el estudio participaron 19 estudiantes de 9no grado, a quienes se organizaron en 5 grupos colaborativos por temas de interes (Pangea, Placas tectonicas, Volcanes, Tsunamis y Terremotos). Las tecnicas que se utilizaron para recopilar los datos fueron: observaciones participativas, grupos focales y analisis de documentos (cuadernos reflexivos y respuestas de los estudiantes a la pregunta central del proyecto). Para el analisis de los datos se aplico la teoria de actividad (CHAT) que concentra la unidad de analisis en la actividad humana en un contexto particular. Los resultados del estudio senalan que las interacciones entre pares, entre pares y docente, asi como entre estudiantes y material didactico son fundamentales en el proceso de aprendizaje. Una mayor interaccion entre pares durante las etapas de planificar y desarrollar los productos finales de la unidad, promueve una mejor comprension de los conceptos de la

  14. La utilizacion de los mapas conceptuales en la ensenanza de biologia y su efecto sobre el dominio del proceso de fotosintesis en los estudiantes universitarios

    NASA Astrophysics Data System (ADS)

    Gonzalez Rivera, Maria M.

    Se investigo el efecto de los mapas conceptuales sobre el dominio del proceso de fotosintesis en estudiantes universitarios. La investigacion utilizo dos estrategias: mapas conceptuales individuales y mapas conceptuales colaborativos, con el fin de investigar si existen diferencias significativas en el dominio del proceso de fotosintesis. El analisis de los datos incluyo aspectos cualitativos y cuantitativos. Se desprende del estudio que el 80% de los estudiantes describen la utilizacion de los mapas conceptuales como una experiencia beneficiosa. El 70% de los estudiantes expreso que los mapas conceptuales son utiles en el aprendizaje del proceso de fotosintesis y el 61% indico que facilitan la comprension de los conceptos. Los hallazgos mas importantes del analisis cuantitativo indican que los estudiantes que utilizaron los mapas conceptuales mejoraron significativamente su desempeno en la posprueba global. Se utilizo la prueba Mann-Whitney para investigar si existian diferencias significativas en la posprueba y preprueba global, el valor de W = 1945.0, para un valor p de 0.00, lo cual establece diferencias significativas. Para determinar si existian diferencias significativas entre la posprueba y preprueba del grupo individual, se realizo la prueba nuevamente. El valor de W correspondio a 490.5, que es significativo, con un valor p de 0.00. Se concluye que existen diferencias significativas entre la ejecucion de la posprueba y preprueba del grupo individual. Los datos proveen suficiente evidencia para sostener que los estudiantes que utilizaron la estrategia de mapas conceptuales individuales mejoraron el dominio del proceso de fotosintesis significativamente. Se realizo nuevamente la prueba para los resultados de posprueba y preprueba del grupo colaborativo. El valor de W correspondio a 446 con un valor p de 0.00. Se concluyo que existen diferencias significativas entre la ejecucion de la posprueba y preprueba del grupo colaborativo. Finalmente, se efectuo una

  15. Hydrogeology of a fractured shale (Opalinus Clay): Implications for deep geological disposal of radioactive wastes

    NASA Astrophysics Data System (ADS)

    Gautschi, Andreas

    2001-01-01

    ême lorsque des fractures et des failles existaient dans certains des intervalles d'essais. Ces mesures sont conformes aux données hydrogéologiques tirées du recoupement des argiles à Opalinus par dix tunnels du Jura plissé du nord de la Suisse. Malgré une tectonique intense, peu de manifestations de faibles venues d'eau ont été rencontrées dans plus de 6600 m de tunnel. Toutes les venues d'eau se sont produites dans des sections de tunnel où le recouvrement est inférieur à 200 m. Les données hydrauliques sont en bon accord avec les données hydrochimiques et isotopiques de l'eau porale des argiles. En se basant sur le grand nombre de données hydrogéologiques, qui portent en partie sur les environnements géologiques particulièrement peu propices, on peut avancer que le transport advectif le long des failles et des fractures n'est pas un facteur susceptible de remettre en question le choix de l'argile à Opalinus comme roche hôte pour le stockage de déchets radioactifs en formation géologique profonde. Resúmen. Dentro del programa suizo de eliminación de residuos radiactivos de alta actividad, se está investigando la posibilidad de utilizar unos esquistos Jurásicos (Arcilla Opalina) como depósito geológico. Las observaciones efectuadas en pozos en arcilla y los resultados de un programa de estudio alemán sobre eliminación de residuos peligrosos han demostrado que, a profundidades de entre 10 y 30 m, la permeabilidad de la Arcilla Opalina decrece en varios órdenes de magnitud. Los ensayos hidráulicos realizados en sondeos más profundos (en intervalos situados a más de 300 m) proporcionaron conductividades hidráulicas inferiores a 10-12 m/s, pese a que algunos de los intervalos interceptaban juntas y fallas. Estas medidas son coherentes con los datos hidrogeológicos de las secciones de Arcilla Opalina existentes en 10 túneles del Jurásico Plegado, al norte de Suiza. A pesar de las fallas extensivas, apenas se hallaron indicios de entrada de

  16. Estudio de eventos dinámicos en ondas milimétricas

    NASA Astrophysics Data System (ADS)

    Cristiani, G.; Martínez, G.; Raulin, J. P.; Giménez de Castro, G.; Rovira, M.

    El estudio de la actividad solar con el telescopio para ondas submilimétricas (SST), nos permite, por vez primera, trabajar con una resolución temporal de milisegundos. Este hecho ha permitido observar emisión nunca antes comprobada, pulsos o flashes extremadamente rápidos provenientes de las regiones activas, los cuales parecen preanunciar fulguraciones en dichas regiones. Se muestra, como ejemplo, una fulguración observada con el telescopio HASTA en Hα, y los pulsos rápidos que la preceden observados con el SST. Para cuantificar la influencia de la atmósfera terrestre en los datos registrados, se está estudiando la variabilidad temporal de las opacidades a las frecuecias de trabajo (212 y 405 Ghz), es decir los rangos de tiempo para los cuales la opacidad puede variar apreciablemente. Con este fin se calcula la eficiencia de cada canal multiplicada por la temperatura del Sol a estas frecuencias (estas son conocidas con una incerteza del 20 %). Se muestran los resultados obtenidos para cada canal, en donde se grafica este producto como función de la opacidad.

  17. Plan for a groundwater monitoring network in Taiwan

    NASA Astrophysics Data System (ADS)

    Hsu, Shiang-Kueen

    suivi des eaux souterraines à Taïwan". D'après ce programme, les données de base concernant les eaux souterraines, comprenant les mesures de niveau et les données de qualité, ont été acquises ; une base de données sûre est en cours d'élaboration, dans le but de gérer l'ensemble des ressources en eau. Cet article présente les buts, les stades de développement et une vue d'ensemble de ce plan. Le plan impose la mise en place de 517 stations de mesures hydrogéologiques et de 990 piézomètres en 17 ans. Selon ce programme, les variations du niveau des nappes doivent être suivies en continu, tandis que des échantillons pour la qualité de l'eau seront prélevés pour analyses uniquement au cours de la phase de foration, puis au moment de la mise en service des piézomètres. En 1996, le Département des Ressources en Eau et la Commission de Planification des Ressources en Eau ont été réunis pour former l'actuel Bureau des Ressources en Eau. Resumen En Taiwan, el rápido crecimiento económico, el aumento en el nivel de vida y los cambios sociales en los últimos años han resultado en un aumento en la demanda de agua. Por su estabilidad en términos de cantidad y calidad, las aguas subterráneas han sido durante años la fuente de agua para usos domésticos, agrícolas e industriales. En los últimos años, sin embargo, el establecimiento de un programa de gestión conjunta de aguas superficiales y subterráneas se ha visto comprometido por la falta de datos correspondientes a estas últimas. En 1992, el Departamento de Recursos de Agua (DWR) inició un programa titulado "Plan de Red de Control de Aguas Subterráneas en Taiwan". Bajo este programa, se están recogiendo datos básicos, incluyendo niveles piezométricos y datos de calidad, y se está construyendo una base de datos con el propósito de gestionar los recursos de agua totales. Este artículo presenta el marco, los objetivos y el estado de implantación del plan, que pretende la construcci

  18. Aceptabilidad del diagnóstico rápido casero para HIV entre hombres gay y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires.

    PubMed

    Balán, Iván C; Carballo-Diéguez, Alex; Marone, Rubén O; Pando, María A; Barreda, Victoria; Avila, María M

    2011-03-01

    El uso del diagnóstico rápido para HIV en Argentina, así como otros países de Latinoamérica, ha sido limitado hasta el momento. Este trabajo reporta los resultados provenientes de un estudio cualitativo realizado entre hombres gays y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires, Argentina. El objetivo principal del mismo fue conocer las ventajas y desventajas que los hombres G&HSH perciben en relación al diagnóstico rápido casero para HIV. Se realizaron ocho grupos focales con 73 participantes en los cuales se discutió acerca de las ventajas y desventajas del uso de los diagnósticos rápidos. Las respuestas fueron codificadas utilizando un programa para análisis de datos cualitativos (NVivo) y analizadas temáticamente. Los participantes describieron numerosas ventajas sobre el uso del diagnóstico rápido casero, aunque algunos reportaron importantes preocupaciones dentro de las cuales se destaca la posibilidad de impulsos suicidas si alguien recibe un resultado positivo estando solo. En términos generales se observó una gran aceptabilidad para el uso del diagnóstico rápido si el mismo es realizado por personal de salud en lugares acondicionados para este fin. PMID:25284951

  19. Cobertura de los sistemas de pensiones y factores asociados al acceso a una pensión de jubilación en México

    PubMed Central

    Murillo-López, Sandra; Venegas-Martínez, Francisco

    2016-01-01

    Resumen Objetivos: obtener estimaciones de indicadores de cobertura de las pensiones por jubilación o retiro para la población mexicana de 65 y más años, y evaluar el impacto que tienen los sistemas de pensiones en las transiciones al retiro de los adultos en edades medias y avanzadas en México. Para ello se utilizan datos microeconómicos provenientes de la Encuesta Nacional de Salud y Envejecimiento. Mediante análisis econométrico se identifican los factores sociodemográficos, económicos, laborales e institucionales que están asociados al acceso a una pensión de jubilación, o bien, a la dependencia de otras fuentes de ingresos. Se encontró que, en México, las transiciones al retiro del mercado de trabajo en las etapas avanzadas del ciclo de vida son limitadas debido a las características eminentemente contributivas de los esquemas de pensiones, los cuales favorecen a la población con trayectorias laborales formales y más estables asociadas a: características de género, oportunidades educativas y posibilidades de inserción en el mercado laboral. PMID:27524936

  20. Obtención de la curva de luz en la ocultación de 35 Sgr por Júpiter el 6 de marzo de 1996

    NASA Astrophysics Data System (ADS)

    Paolantonio, S.; Duffard, R.; Carranza, G.

    La ocultación de la estrella de quinta magnitud 35 Sgr por Júpiter, se produjo el 6 de Marzo de 1996 a las 13 hs. TU. El objetivo era medir el cambio del flujo de la estrella en el ingreso y egreso por el limbo del planeta. Con estos datos se pueden determinar parámetros físicos del planeta (radio, eccentricidad) y de su atmósfera (escala de altura, temperatura, densidad, presión) Para lograr ésto se programó la cámara CCD TH 7896 1024 x 1025 instalada en el telescopio de 1.54 m de Bosque Alegre con el objetivo de lograr 2 imágenes por segundo. De esta forma se obtuvieron 2100 imágenes de la inmersión y otras tantas de la emersión. Hubo que tener grandes precauciones para evitar la saturación del CCD ya que la observación se realizó de día. En este momento las imágenes se encuentran en el Department of Planetary Sciences, Lunar and Planetary Laboratory, University of Arizona, para su reducción.

  1. Estudio multifrecuencia del medio interestelar cercano a HD 192281

    NASA Astrophysics Data System (ADS)

    Arnal, E. M.; Cappa, C. E.; Cichowolski, S.; Pineault, S.; St-Louis, N.

    Una de las causas que modifica la estructura y dinámica del medio interestelar es la acción que los vientos de las estrellas de gran masa ejercen sobre el mismo. En este trabajo, mediante el uso de datos interferométricos obtenidos en la banda de radio en la transición de λ˜21-cm del hidrógeno neutro y de imágenes de la emisión de continuo en las bandas de 408 y 1420 MHz, de imágenes HIRES del satélite IRAS en 60 y 100μm, y de observaciones de continuo obtenidas con radiotelescopios de disco simple en 2695, 4850 y 8350 MHz se ha realizado un estudio multifrecuencia de los efectos que los vientos estelares de HD 192281, una estrella de tipo espectral O5,Vn((f))p, han tenido sobre el medio interestelar que rodea a la misma.

  2. Digitalización de diapositivas del Sol en H α

    NASA Astrophysics Data System (ADS)

    Missio, H.; Montenegro, C.; Montenegro, R.

    El objetivo de este trabajo ha sido el de obtener imágenes digitalizadas de las diapositivas tomadas del Sol en luz de hidrógeno de la línea correspondiente a Hα, y de esta manera llegar a convertir las mismas a un archivo digital para poder ser tratadas luego por computadora y poder contabilizar con exactitud, mediante un programa adecuado para tal fin, las zonas activas del Sol en la imagen digitalizada. En principio, para llegar a esto se pensó en la utilización de medios accesibles, y como detector se utilizó un fototransistor ubicado dentro de un soporte rectangular sobre dos ejes de desplazamiento X e Y. Se han obtenido con este procedimiento imágenes de buena calidad, construídas a partir de tres datos digitalizados en cada barrido que aportan la posición X e Y y la intensidad del pixel en ese punto indicada en 255 tonos de grises.

  3. Estudio multiespectral del remanente de supernova W 28

    NASA Astrophysics Data System (ADS)

    Dubner, G.; Velázquez, P.; Castelletti, G.

    Se presentan observaciones en continuo de radio con muy alta resolución angular y sensibilidad del remanente de supernova (RSN) W28. Las observaciones fueron realizadas con el interferómetro Very Large Array (Estados Unidos), en las configuraciones C y D, en 1415 y 324 MHz. Por la gran extensión de este remanente (diámetro ~ 1o), las observaciones en 1415 MHz se realizaron en modo mosaico, combinando 48 apuntamientos diferentes en una única imagen. En ambas frecuencias los datos se procesaron con el agregado de observaciones de menor resolución angular, a fin de recuperar información en todas las frecuencias espaciales y obtener estimaciones precisas de densidad de flujo. Las imágenes resultantes muestran por primera vez la presencia de extensiones con forma de arco, cuya naturaleza se investiga. Las observaciones en radio se comparan con una imagen óptica de W28, y con la emisión en rayos X, observada con el satélite ROSAT. Este remanente muestra una clara morfología híbrida, tipo cáscara en frecuencias de radio y de centro lleno en las bandas óptica y de rayos X blandos.

  4. Malaysia collaborates with the new york academy of sciences to develop an innovation-based economy.

    PubMed

    Wahome, Michel; Rubinstein, Ellis

    2011-07-01

    If Malaysia is to become a high-income country by 2020, it will have to transform into a knowledge-based, innovation economy. This goal will be achieved by developing an atmosphere conducive to experimentation and entrepreneurship at home; while reaching out to partners across the globe. One of Malaysia's newest partnerships is with the New York Academy of Sciences. The Academy has expertise in innovation and higher education and a long history of promoting science, education, and science-based solutions through a global network of scientists, industry-leaders, and policy-makers. Malaysia's Prime Minister, Dato' Sri Mohd Najib Tun Abdul Razak, leveraged the Academy's network to convene a science, technology, and innovation advisory council. This council would provide practical guidance to establish Malaysia as an innovation-based economy. Three initial focus areas, namely palm-oil biomass utilisation, establishment of smart communities, and capacity building in science and engineering, were established to meet short-term and long-term targets. PMID:22135594

  5. Realistic retrospective dose assessments to members of the public around Spanish nuclear facilities.

    PubMed

    Jiménez, M A; Martín-Valdepeñas, J M; García-Talavera, M; Martín-Matarranz, J L; Salas, M R; Serrano, J I; Ramos, L M

    2011-11-01

    In the frame of an epidemiological study carried out in the influence areas around the Spanish nuclear facilities (ISCIII-CSN, 2009. Epidemiological Study of The Possible Effect of Ionizing Radiations Deriving from The Operation of Spanish Nuclear Fuel Cycle Facilities on The Health of The Population Living in Their Vicinity. Final report December 2009. Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III, Consejo de Seguridad Nuclear. Madrid. Available from: http://www.csn.es/images/stories/actualidad_datos/especiales/epidemiologico/epidemiological_study.pdf), annual effective doses to public have been assessed by the Spanish Nuclear Safety Council (CSN) for over 45 years using a retrospective realistic-dose methodology. These values are compared with data from natural radiation exposure. For the affected population, natural radiation effective doses are in average 2300 times higher than effective doses due to the operation of nuclear installations (nuclear power stations and fuel cycle facilities). When considering the impact on the whole Spanish population, effective doses attributable to nuclear facilities represent in average 3.5×10(-5)mSv/y, in contrast to 1.6mSv/y from natural radiation or 1.3mSv/y from medical exposures. PMID:21827963

  6. Abundancias químicas de las estrellas CP del grupo HgMn μ Leporis y 53 Tauri. II. Boro, Berilio, Carbono, Magnesio, Aluminio y Silicio

    NASA Astrophysics Data System (ADS)

    López García, Z.; Malaroda, S. M.; Faraggiana, R.

    Se determinan las abundancias químicas de los elementos más livianos presentes en dos estrellas CP del grupo HgMn, μ Lep y 53 Tau, utilizando espectros IUE de alta resolución y técnicas de cálculo de espectros sintéticos. Para el cálculo de las líneas se utiliza la lista mas completa de datos atómicos disponible y el programa SYNTHE. Para el cálculo de la abundancia de un elemento se comparan, para cada imagen, los perfiles observados del mayor número de líneas presentes con los perfiles calculados obtenidos por variación de las abundancias iniciales, reteniendo la abundancia para la cual el acuerdo entre las líneas observadas y calculadas es considerado visualmente el mejor. Los resultados obtenidos son comparados con los estimados por la teoría de la difusión.

  7. Impact of rotavirus disease in Spain: an estimate of hospital admissions due to rotavirus.

    PubMed

    Visser, L E; Cano Portero, R; Gay, N J; Martínez Navarro, J F

    1999-01-01

    The epidemiology of rotavirus infection in Spain was investigated using information from existing surveillance systems. Reports from laboratories and data on hospital admissions were used to estimate the number of hospital admissions due to rotavirus infection. Between January 1989 and December 1995 there were 8265 reports of rotavirus identification in the Sistema de Información Microbiológica, a voluntary national laboratory surveillance system. Where age was reported, 89.2% were in children under 5 y old. This represents 21.8% of all pathogens identified in faecal specimens in children of this age group. Between January and December 1994 there were 5639 admissions coded as "infectious intestinal disease" and 8225 as "non-infective gastroenteritis" in children under 5 y of age in the Conjunto Mínimo Básico de Datos, an obligatory hospital admissions surveillance system which covers 83% of public hospitals. Using regression analysis of admission data and laboratory reports it was estimated that rotavirus infection accounted for 3519 (25.3%) of the hospital admissions. We estimate that 4239 admissions attributable to rotavirus occurred in children under 5 y of age in Spain in 1994, a rate of 2.5/1000 population in this age group. These estimates are lower than those published for other countries, where the burden of disease is considered high enough to warrant a national vaccination programme. A cost-effectiveness study with Spanish information is essential before embarking on a national vaccination programme. PMID:10088916

  8. El Proyecto Gémini: informe actualizado y técnica de observación

    NASA Astrophysics Data System (ADS)

    Sahade, J.; Lapasset, E.; Levato, H.

    Se describirá la situación actual en lo que se refiere al desarrollo del Proyecto Gémini en cuanto a su estructura, faz constructiva y programación general. Se informará sobre los planes a desarrollar en el tiempo de verificación científica y puesta a punto del instrumental, a partir de la primera imagen que se obtenga con el telescopio Gemini Norte. Se presentará, además, el plan operativo para observar con los telescopios Gemini tal cual está concebido hasta la fecha, describiéndose el proceso desde el mismo momento en que un investigador decide presentar una propuesta para observar con uno de los telescopios, hasta el archivo y derechos de propiedad sobre los datos. Se decribe también el ``soft" denominado Observing Tool (OT) que es clave en la planificación científica de Gemini y que puede ser utilizado ``off-line" en cualquier PC con un entorno windows.

  9. La enumeración de la soltería femenina en los censos de población: sesgo y propuesta de corrección

    PubMed Central

    McCaa, Robert; Esteve, Albert; Garcia, Joan

    2013-01-01

    Esta investigación tiene como objetivo investigar el efecto que la disolución de las uniones consensuales tiene en los niveles de soltería que proporciona el Censo de Población, niveles derivados de la variable estado civil. Para ello comparamos los datos censales con los de la Encuestas de Demografía y Salud (de ahora en adelante DHS) en aquellos países y años para los que disponemos de ambas fuentes en el mismo año o años adyacentes (Bolivia, Brasil, Colombia y Perú). Los resultados muestran claramente que las proporciones de nunca unidas derivadas de la variable censal ’Estado civil’ son sistemáticamente más elevadas que las estimadas a partir de las DHS. La razón de esta sobreestimación obedece al hecho de que personas que estuvieron en unión libre en el pasado se declaran solteras en el momento del Censo. La elevada proporción de mujeres solteras que tienen hijos según el Censo es una prueba de ello y a su vez una solución efectiva para corregir el sesgo. PMID:25593515

  10. Aceptabilidad del diagnóstico rápido casero para HIV entre hombres gay y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires

    PubMed Central

    Balán, Iván C.; Carballo-Diéguez, Alex; Marone, Rubén O.; Pando, María A.; Barreda, Victoria; Ávila, María M.

    2011-01-01

    Resumen El uso del diagnóstico rápido para HIV en Argentina, así como otros países de Latinoamérica, ha sido limitado hasta el momento. Este trabajo reporta los resultados provenientes de un estudio cualitativo realizado entre hombres gays y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires, Argentina. El objetivo principal del mismo fue conocer las ventajas y desventajas que los hombres G&HSH perciben en relación al diagnóstico rápido casero para HIV. Se realizaron ocho grupos focales con 73 participantes en los cuales se discutió acerca de las ventajas y desventajas del uso de los diagnósticos rápidos. Las respuestas fueron codificadas utilizando un programa para análisis de datos cualitativos (NVivo) y analizadas temáticamente. Los participantes describieron numerosas ventajas sobre el uso del diagnóstico rápido casero, aunque algunos reportaron importantes preocupaciones dentro de las cuales se destaca la posibilidad de impulsos suicidas si alguien recibe un resultado positivo estando solo. En términos generales se observó una gran aceptabilidad para el uso del diagnóstico rápido si el mismo es realizado por personal de salud en lugares acondicionados para este fin. PMID:25284951

  11. Morfología de la Coma del Cometa Hale - Bopp

    NASA Astrophysics Data System (ADS)

    Gil-Hutton, R.; Caballero, M.; Coldwell, G.; Cañada, M.; Godoy, G.; Trozzo, C.; Gómez, G.

    Para lograr comprender plenamente los procesos físicos que se desarrollan en los núcleos cometarios y obtener un modelo que explique, no sólo su actividad, sino también sus efectos sobre la coma, es necesario obtener información detallada para el mayor número de cometas posible, siendo las características más interesantes para estudiar la ubicación de las regiones activas, la presencia de jets, las tasas de producción de gas y polvo y la interacción de la coma con el viento solar. En la actualidad, con técnicas de procesamiento de imágenes y tecnología CCD se pueden obtener este tipo de datos para cometas que ingresan al sistema solar interior y estudiar, de esta manera, la morfología de sus comas, tratando de correlacionar la actividad detectada con algún modelo teórico. En este trabajo se presenta un estudio parcial de la actividad desarrollada por el cometa Hale-Bopp, y sus efectos sobre la morfología de su coma, desde agosto de 1995 hasta la fecha en base a imágenes adquiridas con el telescopio de 0.76 m. de la Estación Astronómica Dr. Carlos Ulrrico Cesco.

  12. Análisis fotométrico-espectroscópico de un par de binarias en NGC 3532

    NASA Astrophysics Data System (ADS)

    Gramajo, L.; González, J. F.

    Presentamos el informe de avance de un proyecto que apunta a la determinación de masas y radios de precisión en estrellas tempranas de cúmulos abiertos mediante el análisis fotométrico-espectroscópico de sistemas binarios detached con baja rotación. Con ello se pretende determinar el estado evolutivo de estas estrellas y confrontar su estructura con modelos estelares teóricos con distinto grado de ``overshooting". Los primeros objetos seleccionados son dos sistemas binarios de espectros dobles (BDA27 y BDA363) detectados en el cúmulo NGC 3532. Presentamos la órbita espectroscópica obtenida para la binaria eclipsante BDA27, para la cual obtuvimos un período de 4.29 días y una razón de masas q=0.62. Derivamos sus parámetros absolutos preliminares usando nuestra curva de velocidad y datos fotométricos existentes en la literatura, y presentamos estimas del alcance de nuestros resultados una vez que hayamos completado nuestras observaciones con nuevas curvas de luz.

  13. Mortality rates decline in Malaysia.

    PubMed

    1991-11-01

    Experiencing remarkable decreases in mortality rates over the past 3 decades, Malaysia currently has one of the lowest mortality rates among developing countries, a rate that compares favorably with those of developed countries. Between 1957 and 1989, the crude death rate dropped from 12.4/1000 population to 4.6. Over the same period, Malaysia recorded even greater decreases in the infant mortality rate, from 75.5/1000 births to 15.2. The Maternal mortality rate also declined from 1.48 in 1970 to 0.24 in 1988. The data indicates that mortality rates vary from state to state, and that rural areas have a higher mortality than urban areas. According to a study by the National Population and Family Development Board, the use of maternal and child health services has played an important role in reducing neonatal, perinatal, infant, child, and maternal mortality rates. Nearly all women in Malaysia receive antenatal services. While the country has achieved great gains on mortality rates, programs focusing on specific age and socioeconomic groups could lead to even greater reductions. The Minister for National Unity and Social Development, Dato Napsiah Omar, has called for the development of programs designed to improve the population's quality of life. PMID:12284509

  14. BAPA Database: Linking landslide occurrence with rainfall in Asturias (Spain)

    NASA Astrophysics Data System (ADS)

    Valenzuela, Pablo; José Domínguez-Cuesta, María; Jiménez-Sánchez, Montserrat

    2015-04-01

    Asturias is a region in northern Spain with a temperate and humid climate. In this region, slope instability processes are very common and often cause economic losses and, sometimes, human victims. To prevent the geological risk involved, it is of great interest to predict landslide spatial and temporal occurrence. Some previous investigations have shown the importance of rainfall as a trigger factor. Despite the high incidence of these phenomena in Asturias, there are no databases of recent and actual landslides. The BAPA Project (Base de Datos de Argayos del Principado de Asturias - Principality of Asturias Landslide Database) aims to create an inventory of slope instabilities which have occurred between 1980 and 2015. The final goal is to study in detail the relationship between rainfall and slope instabilities in Asturias, establishing precipitation thresholds and soil moisture conditions necessary to instability triggering. This work presents the database progress showing its structure divided into various fields that essentially contain information related to spatial, temporal, geomorphological and damage data.

  15. Autoguía para el telescopio 2,15 mts de CASLEO

    NASA Astrophysics Data System (ADS)

    Aballay, J. A.; Casagrande, A. R.; Pereyra, P. F.; Marún, A. H.

    Se está desarrollando un sistema de autoguía para el telescopio de 2,15 mts. El mismo se realizará aprovechando el Offset Guider. Al ocular móvil de éste se vinculará alguna cámara digital (ST4-ST7-CH250) para lograr la visión del objeto. El funcionamiento del equipo será el siguiente: primero, dadas las coordenadas del objeto a observar, se tomarán las coordenadas del telescopio para que, a través de una base de datos, se determine un campo de objetos que sirvan para la cámara de visión, luego, la PC obtendrá el offset entre la estrella de observación y la estrella seleccionada como guía, este valor será trasladado a los motores que posicionarán en forma automática el ocular. Una vez que la estrella es visualizada en la cámara (monitor de PC ) se correrá el programa que guiará el telescopio automáticamente.

  16. Plan for a groundwater monitoring network in Taiwan

    NASA Astrophysics Data System (ADS)

    Hsu, Shiang-Kueen

    suivi des eaux souterraines à Taïwan". D'après ce programme, les données de base concernant les eaux souterraines, comprenant les mesures de niveau et les données de qualité, ont été acquises ; une base de données sûre est en cours d'élaboration, dans le but de gérer l'ensemble des ressources en eau. Cet article présente les buts, les stades de développement et une vue d'ensemble de ce plan. Le plan impose la mise en place de 517 stations de mesures hydrogéologiques et de 990 piézomètres en 17 ans. Selon ce programme, les variations du niveau des nappes doivent être suivies en continu, tandis que des échantillons pour la qualité de l'eau seront prélevés pour analyses uniquement au cours de la phase de foration, puis au moment de la mise en service des piézomètres. En 1996, le Département des Ressources en Eau et la Commission de Planification des Ressources en Eau ont été réunis pour former l'actuel Bureau des Ressources en Eau. Resumen En Taiwan, el rápido crecimiento económico, el aumento en el nivel de vida y los cambios sociales en los últimos años han resultado en un aumento en la demanda de agua. Por su estabilidad en términos de cantidad y calidad, las aguas subterráneas han sido durante años la fuente de agua para usos domésticos, agrícolas e industriales. En los últimos años, sin embargo, el establecimiento de un programa de gestión conjunta de aguas superficiales y subterráneas se ha visto comprometido por la falta de datos correspondientes a estas últimas. En 1992, el Departamento de Recursos de Agua (DWR) inició un programa titulado "Plan de Red de Control de Aguas Subterráneas en Taiwan". Bajo este programa, se están recogiendo datos básicos, incluyendo niveles piezométricos y datos de calidad, y se está construyendo una base de datos con el propósito de gestionar los recursos de agua totales. Este artículo presenta el marco, los objetivos y el estado de implantación del plan, que pretende la construcci

  17. Estudio teórico del CO2. Orbitales de valencia y del ``core''

    NASA Astrophysics Data System (ADS)

    Olalla Gutiérrez, E.

    Hemos calculado las intensidades de las transiciones E1 a los miembros de las series de Rydberg con origen en los orbitales ``no enlazantes'' del dióxido de carbono, especie de conocida relevancia atmosférica. Se han computado, asimismo, los continuos de fotoionización correspondientes a los distintos canales de ionización, representándolos como densidad espectral de fuerza de oscilador frente a la energía del fotón incidente; mostramos los resultados df/dE para la fotoionización total de esta especie en el intervalo 15-60 eV. Todos los cálculos se han llevado a cabo mediante la formulación Molecular del Método de los Orbitales de Defecto Cuántico, MQDO [1,2]. La calidad de los resultados que presentamos se ha evaluado en base a la comparación con los datos, tanto experimentales como teóricos, disponibles en la bibliografía. El acuerdo encontrado es altamente satisfactorio

  18. BAPA Database: a Landslide Inventory in the Principality of Asturias (NW Spain) by Using Press Archives and Free Cartographic Servers

    NASA Astrophysics Data System (ADS)

    Valenzuela, P.; Domínguez-Cuesta, M. J.; Jiménez-Sánchez, M.; Mora García, M. A.

    2015-12-01

    Due to its geological and climatic conditions, landslides are very common and widespread phenomena in the Principality of Asturias (NW of Spain), causing economic losses and, sometimes, human victims. In this scenario, temporal prediction of instabilities becomes particularly important. Although previous knowledge indicates that rainfall is the main trigger, the lack of data hinders the proper temporal forecast of landslides in the region. To resolve this deficiency, a new landslide inventory is being developed: the BAPA (Base de datos de Argayos del Principado de Asturias-Principality of Asturias Landslide Database). Data collection is mainly performed through the gathering of local newspaper archives, with special emphasis on the registration of spatial and temporal information. Moreover, a BAPA App and a BAPA website (http://geol.uniovi.es/BAPA) have been developed to easily obtain additional information from authorities and private individuals. Presently, dataset covers the period 1980-2015, registering more than 2000 individual landslide events. Fifty-two per cent of the records provide accurate dates, showing the usefulness of press archives as temporal records. The use of free cartographic servers, such as Google Maps, Google Street View and Iberpix (Government of Spain), combined with the spatial descriptions and photographs contained in the press releases, makes it possible to determine the exact location in fifty-eight per cent of the records. Field work performed to date has allowed the validation of the methodology proposed to obtain spatial data. In addition, BAPA database contain information about: source, typology of landslides, triggers, damages and costs.

  19. Recovery among adolescents: models for post-treatment gains in drug abuse treatments.

    PubMed

    Joe, George W; Knight, Danica Kalling; Becan, Jennifer E; Flynn, Patrick M

    2014-03-01

    Recovery among adolescents undergoing substance abuse treatment was modeled in terms of pre-treatment motivation, therapeutic relationships, psychological functioning, treatment retention, legal pressures, DSM diagnoses, and client demographics. To address between program differences, a within-covariance matrix, based on 547 youth, was used. Applicability of the results across treatment modalities was also examined. The data were from the NIDA-sponsored DATOS Adolescent study. Results from structural equation models (estimated using Mplus) indicated that higher pre-treatment motivation predicted stronger counselor and in-treatment peer relationships, better counselor relationships and retention predicted less illegal drug use at follow-up, and DSM diagnosis was important in the treatment process. Overall, illegal drug use at follow-up was associated with post-treatment alcohol consumption, cigarette use, condom nonuse, psychological distress, criminality, and school non-attendance. The results document the importance of motivation and therapeutic relationships on recovery, even when taking into account the relative effects of legal pressures, DSM diagnoses, and demographics. PMID:24238715

  20. Telescopio Solar en Hα (HASTA)

    NASA Astrophysics Data System (ADS)

    Fernández Borda, R.; Francile, C.; Bagala, G.; Bauer, O.; Haerendel, G.; Rieger, E.; Rovira, M.

    El Telescopio Solar en Hα (Hα Solar Telescope for Argentina (-HASTA-) fue recientemente instalado en la Estación Astronómica de Altura Carlos Ulrrico Cesco (OAFA) en El Leoncito. Este instrumento estudiará la evolución de las fulguraciones solares desde tierra con alta resolución temporal y espacial. HASTA es un telescopio refractor de 110 mm con una distancia focal de 165 cm, un filtro Lyot sintonizable (±1Å) con un ancho de banda de 0.3 Å y una cámara CCD de alta resolución (1280×1024 pixels). Todo el conjunto es controlado en forma remota por una PC, la cual además adquiere datos del Sistema de Posicionamiento Global (GPS) y de la estación meteorológica. Diseñado para detectar fulguraciones, el instrumento trabaja en dos modos (patrullaje y fulguración) con una resolución espacial de 1.5 arcseg por pixel y una resolución temporal de 2 seg. HASTA comenzó a operar en Mayo de 1998 y, junto con otros tres instrumentos solares, que se están instalando o se instalaron, harán de El Leoncito un polo de observación solar importante en el Hemisferio Sur.

  1. La dinámica demográfica y la desigualdad educativa en Méxicoa

    PubMed Central

    Giorguli Saucedo, Silvia E.; Vargas Valle, Eunice D.; Ulloa, Viviana Salinas; Hubert, Celia; Potter, Joseph E.

    2015-01-01

    En este trabajo se presenta una investigación sobre el vínculo entre los procesos educativos y la dinámica demográfica en México. La tradición del pensamiento sobre población y desarrollo ha partido de la hipótesis de que el ritmo de crecimiento poblacional, el tamaño de las familias y la migración influyen sobre la acumulación de capital humano entre la población en edades escolares. Se explora aquí la relación del desempeño educativo de los jóvenes entre 14 y 23 años y la razón de dependencia juvenil, la fecundidad adolescente y la migración interna e internacional; para ello se utilizan datos agregados a escala municipal del año 2000. El análisis incluye indicadores de la oferta educativa municipal basados en estadísticas administrativas de la SEP. PMID:26146427

  2. Diseno de una Actividad de Aprendizaje Basada en la Argumentacion Dialogica en un curso Virtual de Biotecnologia y su Incidencia en el Desarrollo de Competencias Cientificas

    NASA Astrophysics Data System (ADS)

    Ortiz Benavides, Fedra Lorena

    El proposito de la investigacion fue evaluar la efectividad de una actividad de aprendizaje basado en la argumentacion dialogica en linea y su incidencia en el desarrollo de competencias cientificas. Se fundamenta en la teoria del aprendizaje socio cultural de Vigotsky (1984), los principios del diseno instruccional de la cognicion situada por Hung y Der-Thang (2001) y como estrategia se aplico la argumentacion dialogica utilizando el Modelo Argumentativo de Toulmin MAT (1984). El diseno experimental comparo dos grupos de estudiantes A y B en el curso virtual de Biotecnologia. El grupo A (experimental) desarrollo la discusion a partir de la estrategia disenada para este estudio y el grupo B (control) realizo la discusion desde las actividades tradicionales. El desarrollo de la competencia argumentativa se valoro con el instrumento de evaluacion para argumentacion dialogica en linea propuesta por Clark y Sampson (2008). La evaluacion de las competencias cientificas se realizo a partir de una postprueba. Los datos fueron analizados con pruebas estadisticas no parametricas. Los resultados de la investigacion, indicaron diferencias significativas en el nivel de la competencia argumental en el grupo experimental en comparacion al grupo control. Igualmente se demostro que existe una relacion positiva entre el nivel de desarrollo de la competencia argumentativa y el nivel de desarrollo de las competencias cientificas.

  3. Measurement and evaluation of national family planning programs.

    PubMed

    Mauldin, W P

    1967-03-01

    presentadas en formularios estandarizados, en las siguienies formas: 1. Informes nensuales por áreas administrativas, sobre los actuales servicios de planeamiento familiar proporcionados en la actualidad, de carácter permanente o de larga duración (al presente, esterilización y IUD de acuerdo a las siguientes características del receptor: residencia, edad, paridad (número de hijos vivos por sexo), y donde se enteró del programa, si es posible "clase";(probablemente educación de la madre, pero posiblemente ocupación del esposo, ingreso, o equivalente); prácticas anticonceptivas anteriores; intervalo; y deseo de tener más hijos. En un programa grande estos datos pueden obtenerse en base a una muestra. 2. Informes mensuales sobre la distribución de suministros anticonceptivos (condones, píldoras, sustancias efervescentes, etc.), los primeros suministros deben ir acompañados de un registro de las características del recipiente, como anteriormente; los suministros subsecuentes se regietrarán sólo en volumen bruto. Esto también se aplicará al ritmo, donde éste método se enseñe a un número considerable de mujeres. 3. Informes regulares sobre las actividades de planeamiento familiar de médicos privados, como una estimación del efecto catalítico del programa del gobierno sobre ci sector privado. 4. Datos generates mensuales, ppr áreas admirtistrativas importantes, sabre: visitas domiciliarias, reuniones, cuñas radiates y televisadas, avisos en los periódicos y personal que trabaja. 5. Para propósitos de seguimiento una entrevi eta de campo cada 6 a 12 meses a cada N mujer de las listas para (1) y (2) arriba, en un total de 300 o 400, para conocer las tasas de continuación y las razones de abandono (ej: desea otro hijo, insatisfecha can ci método, otras). Las mue.stras podrían ser de 300 cada una, con una supuesta experiencia de 6, 12, 18 y 24 meses. B. Un buen conjunto de datos sobre costa (datos sobre cotos actulaes atribuíbles directamente al

  4. Poblacion estelar joven embebida en la nube molecular galactica asociada a la fuente IRAS 18236-1205

    NASA Astrophysics Data System (ADS)

    Romero, Ricardo Retes

    2008-06-01

    En esta tesis presento una metodología de seleccion y estudio de la población estelar embebida en la nube molecular galactica asociada a la fuente IRAS 18236-1205. La fuente IRAS posee colores de region Ultra Compacta HII (UCHII) y tiene deteccióon en monosulfuro de carbono (CS), trazador molecular de alta densidad, lo cual da la posibilidad de definir la nube molecular asociada hacia esta region. Lo anterior muestra que esta es buena candidata a región de formación estelar masiva. La metodología de seleccion de la población embebida, est à basada por una parte, en la distribución del gas molecular monoxido de carbono (13CO) asociado a la fuente IRAS, nube molecular seleccionada del mapeo Galactic Ring Survey (GRS) realizado en 13CO. Otros pasos de la seleccion, se basan en los diagramas color-color y color-magnitud con datos del cercano infrarrrojo de 2MASS. Para el estudio de la componente estelar se usaron los catalogos de fuentes puntuales en el cercano, medio y lejano infrarrojo de 2MASS, SPITZER e IRAS, respectivamente. De los diagramas color-color y color-magnitud, usando datos de 2MASS, se construyo un criterio fotométrico para identificar los objetos estelares j ovenes embebidos en la region molecular. Aplicando modelos a la distribución espectral de energía (SED) de algunos ellos, se encontraron parametros estelares de objetos estelares j ovenes embebidos de masa intermedia y alta. Adicionalmente, se encontro un objeto de masa ´ intermedia no identifiado por el catalogo de 2MASS y su efecto sobre el medio interestelar, emision en la banda de [4.5] μm de IRAC-Spitzer asociado a un outflow. Dos de los objetos seleccionados por el criterio fotometrico resultaron ser objetos estelares jovenes de alta e intermedia masa (B1V/B2V y B8V/A0V respectivamente), los cuales deben estar asociados a la emision radiativa responsable de los colores de región UC HII. Otro objeto estelar joven de baja masa (F0V/F5V) fue encontrado en la region de estudio

  5. A protocol for eliciting nonmaterial values through a cultural ecosystem services frame

    PubMed Central

    Gould, Rachelle K; Klain, Sarah C; Ardoin, Nicole M; Satterfield, Terre; Woodside, Ulalia; Hannahs, Neil; Daily, Gretchen C; Chan, Kai M

    2015-01-01

    Servicios Ambientales Culturales Resumen Los deseos, necesidades y valores no materiales de los accionistas influyen frecuentemente sobre el éxito de los proyectos de conservación. Estas consideraciones son difíciles de articular y caracterizar, lo que resulta en entendimiento limitado en el manejo y la política. Concebimos un protocolo de entrevista diseñado para mejorar el entendimiento de los servicios ambientales culturales (SAC). El protocolo inicia con la discusión de actividades relacionadas con ecosistemas (p. ej.: recreación, cacería) y manejo; después señala a los SAC, dando pie a los valores que encierran conceptos identificados en la Evaluación Ambiental del Milenio (2005) y explorado en otras investigaciones sobre SAC. Hicimos pruebas piloto del protocolo en Hawái y Columbia Británica. En cada localidad entrevistamos a 30 individuos de diversos entornos. Analizamos los resultados de las dos localidades para determinar la efectividad del protocolo de entrevista en la obtención de valores no materiales. Los componentes cualitativos y espaciales del protocolo nos ayudaron a caracterizar los valores culturales, sociales y éticos asociados con el ecosistema de múltiples maneras. Los mapas y las preguntas de situación, o de tipo viñeta, ayudaron a los encuestados a articular valores difíciles de discutir. Las preguntas abiertas permitieron a los encuestados expresar una diversidad de valores ambientales y demostraron ser suficientemente flexibles para que los encuestados comunicaran valores que el protocolo no buscaba explícitamente. Finalmente, los resultados sugieren que ciertos valores, aquellos mencionados frecuentemente en la entrevista, son particularmente prominentes para poblaciones particulares. El protocolo puede proporcionar datos eficientes, contextuales y basados en lugar sobre la importancia de atributos ambientales particulares para el bienestar humano. Los datos cualitativos son complementarios para las evaluaciones cuantitativas y

  6. PREFACE: The 3rd ISESCO International Workshop and Conference On Nanotechnology 2012 (IWCN2012)

    NASA Astrophysics Data System (ADS)

    Umar, Akrajas Ali; Yahaya, Muhammad; Mat Salleh, Muhamad

    2013-04-01

    unwavering support dedicated by all the referees. Their tireless work has helped guarantee the high scientific level of this series. Many thanks are also addressed to the ISESCO, COMSATS, MASS, UKM and FST for their financial support. Logistics support provided by IMEN and MNA is also much appreciated. We realized that this volume would never have materialized without the hard work of Ms Siti Khatijah Md Saad who helped the editorial secretariat in many ways communicating with the authors and reviewers and checking and typesetting the papers in the final stage. Finally, great appreciation is addressed to all who have worked hard and given support ensuring that the conference was a success. Editors Associate Professor Dr Akrajas Ali Umar Professor Dr Muhamad Mat Salleh Professor Dato' Dr Muhammad Yahaya IWCN 2012 Organizing Committee International Advisory Board Professor Dato' Dr Muhammad Yahaya (UKM, Malaysia) Dr Faiq Bilal (ISESCO, Morocco) Professor Dr Michael Graetzel (Switzerland) Professor Dr Muhamad Rasat (Malaysia) Prof Dr Masbah R T Siregar (Indonesia) Associate Professor Dr Munetaka Oyama (Japan) Professor Dr Ismat Shah (USA) Professor Dr Muhamad Mat Salleh (Malaysia) Chairman Associate Professor Dr Mohammad Kassim Co-Chairman Dr Mohammad Hafizuddin Haji Jumali Secretary Dr Lorna Jeffry Minggu Treasurer Dr Sharina Abu Hanifah Committee Members Associate Professor Dr Mohd Azmi Abd Hamid Associate Professor Dr Akrajas Ali Umar Dr Zahari Ibarahim Dr Rozidawati Awang Dr Farah Hannan Anuar Secretariat Dr Khuzaimah Mohd Firdauz Ismail Izura Izzuddin Nor Huwaida Janil Jamil Siti Khatijah Md Saad Noor Razinah Rahmat Mark Lee Wun Fui Ng Kim Hang Lee Thian Khoon Law Kung Pui Choong Yan Yi

  7. Lunar Phases and Earthly Events: Beliefs from Different Education Levels. (Spanish Title: Fases de la Luna y Acontecimientos Terrestres: Creencia de Distintos Niveles de Instrucción.) As Fases da Lua e os Acontecimentos Terrestres: a Crença de Diferentes Níveis de Instrução

    NASA Astrophysics Data System (ADS)

    Darroz, Luiz Marcelo; da Rosa, Cleci Teresinha Werner; Alves Vizzotto, Patrick; Becker da Rosa, Álvaro

    2013-12-01

    This article presents the result of a research carried out in the first semester of 2013 with a group of 80 subjects from different education levels. In this research, we sought to investigate the earthly events that this group of people attributes to the phenomenon of lunar phases. For data collection we used semi-structured interviews guided by questions that aimed to keep the focus on subjects of the investigation. Interviews were recorded and transcribed, and the results were compared to scientific studies in the area after being quantitatively and qualitatively analyzed. Research data showed that the Moon and the phenomenon of lunar phases still fascinate and raise the interest of people. However, the lack of knowledge to find correct explanations to the phenomena involving the moon ends up originating a series of beliefs about its influence on earthly events. En este artículo se presenta el resultado de una investigación realizada en el primer semestre de 2013 con a un grupo de 80 individuos de distintos niveles de instrucción. En esta investigación, tratamos de averiguar cuáles son los acontecimientos terrestres que este grupo de personas atribuye al fenómeno las fases lunares. Como instrumento de colecta de datos, se emplearon entrevistas semiestructuradas guiadas por preguntas que trataban de mantener la atención de los entrevistados en el objeto investigado. Las entrevistas fueron grabadas y transcriptas, y los resultados, después de ser analizados cuantitatativa y cualitativamente, fueron confrontados con estudios científicos del área. Los datos de la investigación demuestran que la Luna y de sus fases continúan fascinando y despertando el interés de la población. Sin embargo, la falta de conocimientos para encontrar explicaciones correctas relacionadas a los fenómenos que ocurren con el astro acaba originando una serie de creencias en la población sobre su influencia en los sucesos terrestres. Apresenta-se neste artigo o resultado de uma

  8. Diagnóstico y cinética de plasmas de NxOy y aire a baja presión. Aplicaciones atmosféricas

    NASA Astrophysics Data System (ADS)

    Tanarro Onrubia, Isabel

    Los procesos cinéticos que tienen lugar en plasmas de óxidos de nitrógeno y de aire presentan relevancia en diferentes campos de investigación como son los relativos al control de contaminantes atmosféricos emitidos en procesos de combustión, a su formación en las superficies de las naves supersónicas y los vehículos espaciales al entrar en la atmósfera, o a su presencia en la ionosfera terrestre. En general, los fenómenos que tienen lugar en sistemas tan alejados del equilibrio termodinámico como los plasmas luminiscentes, son capaces de originar determinadas especies intermedias y productos finales de reacción a temperaturas y presiones mucho menores que las de otros procedimientos físico-químicos; y hacen posible reproducir y caracterizar en laboratorio ciertas especies inestables y mecanismos primordiales de la alta atmósfera. Por otra parte, las técnicas de resolución temporal aplicadas a plasmas modulados en amplitud resultan notablemente más sensibles que las medidas estacionarias para estimar la relevancia de los distintos mecanismos elementales o incluso para determinar sus constantes de velocidad. En este trabajo se presenta un estudio espectroscópico y espectrométrico comparativo de plasmas de óxidos de nitrógeno y de aire a baja presión (0.001-1 mbar) generados en descargas de cátodo hueco continuas o moduladas, y se propone un modelo cinético único y relativamente sencillo, que explica satisfactoriamente los comportamientos observados en todos ellos. Dicho modelo se basa en la resolución de un sistema de ecuaciones diferenciales dependientes del tiempo, que incluye los mecanismos elementales de disociación e ionización de los precursores y los productos, reacciones homogéneas entre especies atómicas, iónicas y moleculares, y reacciones heterogéneas. Al abordar estos sistemas, se constata una gran carencia de datos experimentales o teóricos sobre secciones eficaces o constantes de velocidad para las reacciones de

  9. The la Plata Astronomical Data Center

    NASA Astrophysics Data System (ADS)

    Marraco, H. G.

    1990-11-01

    RESUMEN. El Centro de Datos Astron6micos tiene su sede en la Facuitad de Ciencias Astron6micas y Geofisicas d la Universidad Nacional de La Plata y funciona por convenio entre esta facultad y el Centre des Stellaires de la Universite' Louis Pasteur en Estrasburgo (CDS), Francia. La finalidad de este centro es la de proveer a los astr6nomos del area con copias de los alrededor de 500 acumulados y/o preparados por el CDS a la vez que promover la producci6n y/o acumulaci6n de en el rea. Para la realizaci6n de esta tarea se cuenta con el apoyo del Centro Superior para el Procesamiento de la Informaci6n (CESPI) de la UNLP cuyos equipos se describen. Las tareas que se estan realizando incluyen la distribuci6n de SIMBAD a los astr6nomos argentinos y se efectuan ensayos de distribuci6n en linea de CD-ROM TEST DISK del Astronomical Data Center (ADC) de la NASA que contiene los 31 mas solicitados por los astr6nomos de todo el mundo. ABSTRACl The La Plata Astronomical Data Center operates by an agreement between the Facultad de Ciencias Astron6micas y Geofisicas at La Plata University and the Centre des Donnees Stellaires of Louis Pasteur University at Strasbourg (CDS), France. The purpose of the Center is to provide to the area astronomers with copies of the catalogs they need amongst those stored and/or prepared at CDS. At the same time the center will act of the astronomical data produced within its area. K words: DATA ANALYSIS

  10. Nuevas Galaxias Seyfert 1 Australes

    NASA Astrophysics Data System (ADS)

    Maza, J.; Ruiz, M. T.

    1987-05-01

    En 1984 se inició una extensión del "survey" de Tololo que de- sarrollara en 1975 Smith, con la cámara Curtis-Schmidt y el prisma UV delgado. Utilizando placas IIIaJ horneadas, sin filtro, expues tas 90 minutos sin ensanchamiento se han obtenido a la fecha más de 150 placas que cubren la zona entre -20° y -45° a latitudes galácticas mayores de 20°; se presenta un detalle de las franjas que comprende el survey Calan-Tololo, indicando el grado de completitud de las mismas. Se ha encontrado un gran número de galaxias con líneas de emisión entre las cuales las más frecuentes, más de 300, son galaxias irregulares con formación estelar violenta ("starburst galaxies"). Se ha encontrado un número de cuasares cercano a 100; casi todos ellos tienen la linea Lyman alfa en la zona entre 3300 y 5300 A, que corresponde a un rango de corrimientosal rojo 1.7< z <3.3 el cuasar con mayor corri- miento al rojo encontrado a la fecha en el survey tiene z = 3.1. La información detallada sobre cuasares y galaxias tipo "starburst" será presentada en otro lugar. Entre los objetos más interesantes encontrados en el survey Calán- Tololo destacan unas 50 nuevas galaxias Seyfert 1. Estas galaxias han sido encontradas por su fuerte exceso UV y su brillante núcleo, más que por sus intensas lineas de emisión. Hemos observado espectroscópicamente, en el Observatorio Interamericano de Cerro Tololo, 37 de ellas para las cuales se presentan cartas de identificación, coordenadas y los datos espectroscópicos obtenidos.

  11. Fotometría UBVI en NGC 6231

    NASA Astrophysics Data System (ADS)

    Baume, G. L.; Vázquez, R. A.; Feinstein, A.

    Se ha realizado fotometría CCD UBVI en la zona del cúmulo abierto NGC 6231, habiéndose observado 1062 estrellas hasta una magnitud V≈ 19. Esto posibilita tener una imagen clara de la parte inferior de la secuencia principal del cúmulo. Combinando nuestros datos con tipos espectrales tomados de la literatura pudimos re-derivar la ley de absorción en dirección a este cúmulo y encontrar que los valores de R muestran variaciones de estrella a estrella. La secuencia principal inferior muestra también algunos rasgos intrigantes: hay un codo notorio en V≈ 13.5 seguido por un gran ``spread'' de magnitudes a color constante entre las estrellas débiles y una inusualmente alta densidad de estrellas a lo largo de una banda que se extiende 1.5 mag encima de la ZAMS. Los cálculos indican que el número esperado de estrellas de campo en dirección al cúmulo debería ser menor que el observado. Una re-evaluación de las funciones de luminosidad y masa dentro de los límites -7.5 < MV < 1.5 mag y 2 Msolar < M arroja pendientes planas para ambas funciones, lo que parece ser típico de cúmulos muy jóvenes. Todos estos rasgos son congruentes con un escenario joven donde las estrellas en fase de contracción están arribando a la secuencia principal.

  12. Estudio de la fotoabsorción y fotoionización de la molécula de alta relevancia atmosférica no a través de los estados Rydberg con la metodología MQDO

    NASA Astrophysics Data System (ADS)

    Bustos, E.; Velasco, A. M.; Martín, I.; Lavín, C.

    Los procesos de fotoionización son de una importancia fundamental [1] y encuentran aplicación en un gran número de contextos científicos: Astrofísica [2], química de las radiaciones, biología. Los investigadores de dichos campos, necesitan de valores de fiables de secciones eficaces para la fotoionización parcial, la Fotoabsorción, así como para los procesos de fotofragmentación en amplios intervalos espectrales, particularmente en estudios de modelización [3-5]. En este trabajo se ha centrado la atención sobre el oxido nítrico, que se ha considerado apropiado y relevante por varios motivos: por el trascendental papel que representa en la física y química de la alta atmosfera [6], aparte de por estar íntimamente relacionado con los problemas de contaminación. Los procesos de recombinación disociativa [7] del NO, donde los estados Rydberg se encuentran directamente implicados, son relevantes, por ejemplo, en las regiones E y F de la ionosfera [7]. En este trabajo se estudia la fotoionización del NO desde el estado fundamental con la versión molecular del método del orbital de defecto cuántico (MQDO). Para ello se calcula el diferencial de las fuerzas de oscilador parciales que constituyen los canales de fotoionización del NO desde el estado fundamental. La continuidad del diferencial de fuerza de oscilador calculada a través del umbral de fotoionización, esto es, en las regiones del espectro discreta y del continua, se adopta como criterio de calidad la escasez de datos comparativos [8].

  13. [In Process Citation].

    PubMed

    Blázquez, Ferrán Padrós; Navarro Contreras, Gabriela; Garcidueñas Gallegos, Diana; Fulgencio Juárez, Mónica

    2016-01-01

    Introducción: la obesidad es una enfermedad asociada a diferentes trastornos físicos y emocionales que inciden en la calidad de vida y que representan un problema de elevada prevalencia en el mundo. La etiología es múltiple y compleja; se ha señalado la culpa como consecuencia del sobrepeso y, al mismo tiempo, como factor asociado al aumento de peso. En México no existen instrumentos para evaluar la culpa por obesidad y sobrepeso en niños y adolescentes. Objetivos: analizar la fiabilidad y validez de la Escala de Culpa por Obesidad o Sobrepeso para Niños y Adolescentes (ECOSNA) en población de Morelia (México). Material y métodos: se elaboró una versión preliminar basada en la bibliografía que se sometió a la revisión de jueces expertos. La escala obtenida de 6 ítems se aplicó a una muestra de 1.418 estudiantes de educación básica de 7 a 15 años. Se realizó un análisis factorial confir- matorio y se estudió la relación de la escala con otras variables como autoestima, sintomatología depresiva y ansiedad. Resultados: la escala resultó unifactorial, se obtuvo un índice alfa de Cronbach de 0,853. La escala ECOSNA mostró una correlación moderada e inversa con la escala de autoestima, y directa y baja con la sintomatología depresiva y la ansiedad clínica. Conclusión: los datos empíricos indican que la escala presenta una validez y confiabilidad satisfactorias. PMID:27238779

  14. Host Plants of Xylosandrus mutilatus in Mississippi

    SciTech Connect

    Stone, W.D.; Nebeker, T.E.; Gerard, P.D.

    2007-03-15

    Host range of Xylosandrus mutilatus (Blandford) in North America is reported here for the first time. Descriptive data such as number of attacks per host, size of stems at point of attacks, and height of attacks above ground are presented. Hosts observed in Mississippi were Acer rubrum L., Acer saccharum Marsh., Acer palmatum Thunb., Ostrya virginiana (Mill.) K. Koch., Cornus florida L., Fagus grandifolia Ehrh., Liquidamber styraciflua L., Carya spp., Liriodendron tulipifera L., Melia azedarach L., Pinus taeda L., Prunus serotina Ehrh., Prunus americana Marsh., Ulmus alata Michaux, and Vitus rotundifolia Michaux. Liquidamber styraciflua had significantly more successful attacks, significantly higher probability of attacks, and significantly higher number of adult beetles per host tree than did Carya spp., A. rubrum, and L. tulipifera. This information is relevant in determining the impact this exotic beetle may have in nurseries, urban areas, and other forestry systems where this beetle becomes established. (author) [Spanish] El rango de hospederos de Xylosandrus mutilatus (Blandford) en America del Norte esta reportado aqui por la primera vez. Se presentan datos descriptivos como el numero de ataques por hospederos, el tamano de los tallos en el punto de ataque y la altura por encima del nivel de tierra de los ataques. Los hospederos observados en el estado de Mississippi fueron Acer rubrum L., Acer saccharum Marsh., Acer palmatum Thunb., Ostrya virginiana (Mill.) K. Koch., Cornus florida L., Fagus grandifolia Ehrh., Liquidamber styraciflua L., Carya spp., Liriodendron tulipifera L., Melia azedarach L., Pinus taeda L., Prunus serotina Ehrh., Prunus americana Marsh., Ulmus alata Michaux y Vitus rotundifolia Michaux. Liquidamber styraciflua tuvo ataques significativamente mas exitosos, una probabilidad significativamente mas alta de ataques y un numero significativamente mayor de adultos de escarabajos por arbol hospedero que Carya spp., A. rubrum y L. tulipifera

  15. Estudio del sistema simbiótico AR Pavonis

    NASA Astrophysics Data System (ADS)

    Quiroga, C.; Brandi, E.; Ferrer, O.; García, L.; Barbá, R.

    Se presenta un estudio espectroscópico y polarimétrico de la binaria eclipsante AR Pavonis a partir de observaciones obtenidas con el telescopio de 2.15 m. del CASLEO (San Juan). El estudio de la naturaleza del sistema se realizó a través del análisis de algunos espectros reunidos entre los años 1990 y 1995 y de datos polarimétricos correspondientes al intervalo 1995 y 1997. El análisis espectroscópico indica que AR Pav está compuesta por una gigante roja M3.7 y una componente caliente compacta, con una temperatura mayor a 90000 K y una luminosidad del orden de 500Lsolar. A lo largo del período orbital, las variaciones observadas en flujo y en velocidades radiales, reflejan que las emisiones permitidas se forman en una región que rodea la componente caliente. El estudio de la polarización lineal de AR Pav indica que además de una componente interestelar, existe una componente intrínseca del sistema que varía temporalmente y con la longitud de onda de la luz polarizada. El distinto comportamiento del grado de polarización y del ángulo de posición observado en fases diferentes, sugiere que distintos mecanismos pueden estar actuando, dependiendo de la región de scattering observado a lo largo de la línea de la visual.

  16. International Celestial Reference Frame (ICRF): mantenimiento y extensión

    NASA Astrophysics Data System (ADS)

    Ma, C.; Arias, E. F.; Eubanks, T.; Fey, A. L.; Gontier, A.-M.; Jacobs, C. S.; Sovers, O. J.; Archinal, B. A.; Charlot, P.

    A partir de enero de 1998 el sistema de referencia celeste convencional está representado por el International Celestial Reference System (ICRS) y materializado a través de las coordenadas VLBI del conjunto de radiofuentes extragalácticas que conforman el International Celestial Reference Frame (ICRF). La primera realización del ICRF, fue elaborada en 1995 por un grupo de expertos designado por la IAU, la que encomendó al International Earth Rotation Service el mantenimiento del ICRS, del ICRF y del vínculo con marcos de referencia en otras frecuencias. Una primera extensión del ICRF se realizó entre abril y junio de 1999, con el objetivo primario de proveer posiciones de radiofuentes extragalácticas observadas a partir de julio de 1995 y de mejorar las posiciones de las fuentes ``candidatas" con la inclusión de observaciones adicionales. Objetivos secundarios fueron monitorear a las radiofuentes para verificar que siguen siendo adecuadas para realizar al ICRF y mejorar las técnicas de análisis de datos. Como resultado del nuevo análisis se obtuvo una solución a partir de la cual se construyó la primera extensión del ICRF, denominada ICRF - Ext.1. Ella representa al ICRS, sus fuentes de definición se mantienen con las mismas posiciones y errores que en la primera realización del ICRF; las demás radiofuentes tienen coordenadas mejor determinadas que en ICRF; el marco de referencia se densificó con el agregado de 59 nuevas radiofuentes.

  17. [Not Available].

    PubMed

    Ballesteros-Pomar, María; Villar-Taibo, Rocío; Calleja-Fernández, Alicia; Pintor-de-la-Maza, Begoña; Álvarez-Del-Campo, Cecilia; Vidal-Casariego, Alfonso; Cano-Rodríguez, Isidoro

    2016-01-01

    Los datos del estudio PREDYCES® nos revelaron que en España la desnutrición relacionada con la enfermedad (DRE) afecta a uno de cada cuatro pacientes hospitalizados. Esta cifra aumenta hasta el 36,8% en los pacientes hematológicos. Se calcula que un 20% de los pacientes oncológicos muere por complicaciones relacionadas con la DRE. Nuestro grupo se planteó en 2011 comenzar la implantación de un cribado nutricional en los servicios con mayor riesgo de DRE. La presente revisión trata de describir todo el proceso que hemos seguido para mejorar la situación nutricional en los pacientes ingresados en el Servicio de Hematología del Complejo Asistencial Universitario de León (CAULE), mayoritariamente con diagnóstico de neoplasias hematológicas. En un primer estudio piloto, detectamos una alta prevalencia de desnutrición, que tendió a aumentar durante la hospitalización. Además, solo el 8,3% los enfermos valorados recibieron algún tipo de soporte nutricional y no se estaban cubriendo sus necesidades ni calóricas ni proteicas, lo que se asociaba a un peor pronóstico. Por este motivo, nos decidimos a implantar de manera sistemática un cribado y una intervención nutricional adecuada, que comenzó en 2011 y que ha recibido el reconocimiento como Buena Práctica del Sistema Nacional de Salud. PMID:27269220

  18. Factores socio-económicos asociados a la percepción de situación socioeconómica entre adultos mayores de dos países latinoamericanos

    PubMed Central

    Brenes-Camacho, Gilbert

    2014-01-01

    El objetivo principal del artículo es estudiar la asociación entre la percepción subjetiva sobre la situación económica propia y una serie de medidas objetivas de bienestar socioeconómico –fuentes de ingresos, tenencia de vivienda, nivel educativo y transferencias familiares informales de dinero- entre adultos mayores de dos países Latinoamericanos: México y Costa Rica. Los datos se obtienen de las primeras rondas de dos encuestas sobre envejecimiento: CRELES para Costa Rica y ENASEM para México. La variable dependiente más importante se obtiene de las respuestas a las pregunta “¿Cómo califica su situación económica actual?” en Costa Rica y “¿Diría usted que su situación económica es…?” en México. Para ambas encuestas, las respuestas se codificaron en forma binaria; el código 0 representa las categorías Excelente, Muy buena y Buena, y el código 1 representa a las categorías Regular y Mala. Se encontró que el ingreso por jubilación es un importante determinante de la percepción de bienestar en ambos países. En Costa Rica, el ingreso del cónyuge y la tenencia de vivienda son importantes predictores de la percepción de bienestar, mientras que en México, los ingresos por transferencias están fuertemente asociados con dicha percepción. PMID:25360057

  19. Acceptability of an Embodied Conversational Agent-based Computer Application for Hispanic Women

    PubMed Central

    Wells, Kristen J.; Vázquez-Otero, Coralia; Bredice, Marissa; Meade, Cathy D.; Chaet, Alexis; Rivera, Maria I.; Arroyo, Gloria; Proctor, Sara K.; Barnes, Laura E.

    2015-01-01

    There are few Spanish language interactive, technology-driven health education programs. Objectives of this feasibility study were to: 1) learn more about computer and technology usage among Hispanic women living in a rural community; and 2) evaluate acceptability of the concept of using an embodied conversational agent (ECA) computer application among this population. A survey about computer usage history and interest in computers was administered to a convenience sample of 26 women. A sample video prototype of a hospital discharge ECA was administered followed by questions to gauge opinion about the ECA. Data indicate women exhibited both a high level of computer experience and enthusiasm for the ECA. Feedback from community is essential to ensure equity in state of the art dissemination of health information. Hay algunos programas interactivos en español que usan la tecnología para educar sobre la salud. Los objetivos de este estudio fueron: 1) aprender más sobre el uso de computadoras y tecnología entre mujeres Hispanas que viven en comunidades rurales y 2) evaluar la aceptabilidad del concepto de usar un programa de computadora utilizando un agente de conversación encarnado (ECA) en esta población. Se administro una encuesta sobre el historial de uso y del interés de aprender sobre computadoras fue a 26 mujeres por muestreo de conveniencia. Un ejemplo del prototipo ECA en forma de video de un alta hospitalaria fue administrado y fue seguido por preguntas sobre la opinión que tenían del ECA. Los datos indican que las mujeres mostraron un alto nivel de experiencia con las computadoras y un alto nivel de entusiasmo sobre el ECA. La retroalimentación de la comunidad es esencial para asegurar equidad en la diseminación de información sobre la salud con tecnología de punta. PMID:26671558

  20. [In Process Citation].

    PubMed

    Gómez-Candela, Carmen; Pérez Fernández, Laura; Sanz Paris, Alejandro; Burgos Peláez, Rosa; Matía Martín, Pilar; García Almeida, José M; Martín Palmero, Ángela

    2016-01-01

    Introducción: la malnutrición es un problema de primer orden en el paciente hospitalizado que prolonga la estancia hospitalaria y la tasa de infecciones. El paciente diabético representa un porcentaje importante de la población hospitalizada. El estudio VIDA tiene como objetivo analizar el estado nutricional de pacientes ancianos con diabetes hospitalizados en España.Objetivo: describir la población del estudio VIDA, incluyendo datos del perfil bioquímico y antropométrico en el momento del ingreso.Métodos: estudio multicéntrico, transversal, observacional llevado a cabo en 1098 pacientes mayores de 65 años. Se incluyeron 35 hospitales españoles.Resultados: la edad media de los pacientes ingresados fue 78 ± 7,1 años. El motivo de ingreso más frecuente fueron las infecciones respiratorias (32,4%). El 51,2% estaban diagnosticados de diabetes desde hacía más de 10 años. Un 33,09% recibía tratamiento con insulina. Un 39,07% presentaba riesgo de malnutrición y un 21,22% estaba mal nutrido en el momento del ingreso. Se encontró mayor prevalencia de malnutrición en el grupo de mujeres (p < 0,0002)Conclusiones: el estudio VIDA es el primero que analiza el estado nutricional de una cohorte de pacientes ancianos diabéticos en España. Enlos resultados de este proyecto se concluye que un 21,2% de la muestra presenta malnutrición. Esta condición es edad y sexo dependiente, y puede empeorar la tasa de mortalidad. PMID:27019239

  1. Estimaciones de Prevalencia del VIH por Género y Grupo de Riesgo en Tijuana, México: 2006

    PubMed Central

    Iñiguez-Stevens, Esmeralda; Brouwer, Kimberly C.; Hogg, Robert S.; Patterson, Thomas L.; Lozada, Remedios; Magis-Rodriguez, Carlos; Elder, John P.; Viani, Rolando M.; Strathdee, Steffanie A.

    2010-01-01

    OBJETIVO Estimar la prevalencia del VIH en adultos de 15-49 años de edad en Tijuana, México - en la población general y en subgrupos de riesgo en el 2006. METODOS Se obtuvieron datos demográficos del censo Mexicano del 2005, y la prevalencia del VIH se obtuvo de la literatura. Se construyó un modelo de prevalencia del VIH para la población general y de acuerdo al género. El análisis de sensibilidad consistió en estimar errores estándar del promedio-ponderado de la prevalencia del VIH y tomar derivados parciales con respecto a cada parámetro. RESULTADOS La prevalencia del VIH es 0.54%(N = 4,347) (Rango: 0.22%–0.86%, (N = 1,750–6,944)). Esto sugiere que 0.85%(Rango: 0.39%–1.31%) de los hombres y 0.22%(Rango: 0.04%–0.40%) de las mujeres podrían ser VIH-positivos. Los hombres que tienen sexo con hombres (HSH), las trabajadoras sexuales usuarias de drogas inyectables (MTS-UDI), MTS-noUDI, mujeres UDI, y los hombres UDI contribuyeron las proporciones más elevadas de personas infectadas por el VIH. CONCLUSIONES El número de adultos VIH-positivos entre subgrupos de riesgo en la población de Tijuana es considerable, marcando la necesidad de enforcar las intervenciones de prevención en sus necesidades específicas. El presente modelo estima que hasta 1 en cada 116 adultos podrían ser VIH-positivos. PMID:19685824

  2. Efectos combinados de la ampliación de la atención primaria de salud y de las transferencias condicionadas de dinero en efectivo sobre la mortalidad infantil en Brasil, 1998–2010*

    PubMed Central

    Guanais, Frederico C.

    2015-01-01

    Objetivos. Examiné los efectos combinados del acceso a la atención primaria mediante el Programa de Salud Familiar (PSF) y las transferencias condicionadas de dinero en efectivo del Programa Bolsa Familia (PBF) sobre la mortalidad infantil posneonatal (MIPN) en Brasil. Métodos. Empleé un análisis ecológico longitudinal usando datos en panel de 4 583 municipios brasileños de 1998 al 2010, con 54 253 observaciones en total. Estimé modelos de regresión de efectos fijos por mínimos cuadrados ordinarios, con la tasa de MIPN como la variable dependiente y el PSF, el PBF y sus interacciones como las principales variables independientes de interés. Resultados. La asociación de una mayor cobertura del PSF con una menor tasa de MIPN se volvió más fuerte conforme aumentaba la cobertura del PBF. En los promedios de todas las demás variables, cuando la cobertura de PBF era 25%, la MIPN predicha fue 5,24 (intervalo de confianza [IC] de 95% = 4,95, 5,53) para una cobertura del PSF de 0%, y de 3,54 (IC de 95% = 2,77, 4,31) para una cobertura del PSF de 100%. Cuando la cobertura del PBF era de 60%, la MIPN predicha fue 4,65 (IC de 95% = 4,36, 4,94) para una cobertura del PSF de 0%, y de 1,38 (IC de 95% = 0,88, 1,89) para una cobertura del PSF de 100%. Conclusiones. El efecto del PSF depende de la ampliación del PBF. Para las poblaciones empobrecidas y subatendidas, la combinación de intervenciones tanto del lado de la oferta como del lado de la demanda podría ser necesaria para mejorar los resultados en salud.

  3. [In Process Citation].

    PubMed

    Mauro-Martin, Ismael San; De la Calle-de la Rosa, Licia; Sanz-Rojo, Sara; Garicano-Vilar, Elena; Ciudad-Cabañas, María José; Collado-Yurrita, Luis

    2016-01-01

    Introducción: las enfermedades cardiovasculares (EC) constituyen la principal causa de muerte a nivel mundial. La etiología es multifactorial, pueden influir diversos factores como la dieta, los hábitos de vida, el nivel de ejercicio físico o la carga genética. El gran número de genes implicados, así como sus diversas variantes, pueden influir sobre el riesgo de padecer enfermedades cardiovasculares por medio de distintas vías.Objetivo: determinar la relación existente entre diferentes polimorfismos genéticos y el riesgo individual de EC en población infantil y adulta.Métodos: se llevó a cabo una búsqueda bibliográfica utilizando la base de datos PubMed. La búsqueda se limitó a un periodo de diez años y a metaanálisis realizados en humanos.Resultados: se establece relación entre el riesgo de enfermedad cardiovascular y los siguientes polimorfismos genéticos: cromosoma 9p21, apolipoproteína A5, apolipoproteínas E2, E3 y E4, gen PPARG o PPARϒ, genes implicados en el metabolismo lipídico, gen MTHFR, citocromo P450, factor V de coagulación o factor de Leiden (FVL) y gen VKORC.Conclusiones: Se han identificado un gran número de genes relacionados con la enfermedad cardiovascular. La carga genética puede influir de manera directa o indirecta sobre el riesgo cardiovascular, modificando factores de riesgo para enfermedad cardiovascular o actuando sobre la medicación empleada para tratarla. PMID:27019250

  4. Intake of energy and nutrients; harmonization of Food Composition Databases.

    PubMed

    Martinez-Victoria, Emilio; Martinez de Victoria, Ignacio; Martinez-Burgos, M Alba

    2015-01-01

    Food composition databases (FCDBs) provide detailed information about the nutritional composition of foods. The conversion of food consumption into nutrient intake need a Food composition database (FCDB) which lists the mean nutritional values for a given food portion. The limitations of FCDBs are sometimes little known by the users. Multicentre studies have raised several methodology challenges which allow to standardize nutritional assessments in different populations and geographical areas for food composition and nutrient intake. Differences between FCDBs include those attributed to technical matters, such as description of foods, calculation of energy and definition of nutrients, analytical methods, and principles for recipe calculation. Such differences need to be identified and eliminated before comparing data from different studies, especially when dietary data is related to a health outcome. There are ongoing efforts since 1984 to standardize FCDBs over the world (INFOODS, EPIC, EuroFIR, etc.). Food composition data can be gathered from different sources like private company analysis, universities, government laboratories and food industry. They can also be borrowed from scientific literature or even from the food labelling. There are different proposals to evaluate the quality of food composition data. For the development of a FCDB it is fundamental document in the most detailed way, each of the data values of the different components and nutrients of a food. The objective of AECOSAN (Agencia Española de Consumo Seguridad Alimentaria y Nutrición) and BEDCA (Base de Datos Española de Composición de Alimentos) association was the development and support of a reference FCDB in Spain according to the standards to be defined in Europe. BEDCA is currently the only FCDB developed in Spain with compiled and documented data following EuroFIR standards. PMID:25719784

  5. Precisión de las velocidades radiales obtenidas con el REOSC

    NASA Astrophysics Data System (ADS)

    González, J. F.; Lapasset, E.

    Complementando una línea de trabajo iniciada con anterioridad discutimos la estabilidad del espectrógrafo REOSC de CASLEO en DC para la medición de velocidades radiales en base al análisis de observaciones realizadas en enero y abril de 1997. En esas oportunidades obtuvimos 26 espectros de estrellas patrones y 27 espectros de 3 estrellas usadas como estrellas de referencia en nuestro programa de cúmulos abiertos. Además tomamos 26 espectros de crepúsculo con el telescopio en posiciones cubriendo el rango H=-4,+4 y δ =-90,+30. Mediante correlaciones cruzadas derivamos la velocidad de 19 órdenes en cada uno de estos espectros. En base a un análisis estadístico de los datos obtenidos discutimos la contribución de los distintos factores que afectan a la dispersión de lectura observada. En particular, la flexión del instrumento no introduciría errores significativos cuando se observa con masas de aire menores que 2.0. La dispersión de los valores de velocidad medidos para espectros de alta relación S/N de una misma estrella resultó del orden de 0.5 km/s. La comparación con los valores de velocidad publicados por distintos autores para las estrellas patrones no permite distinguir ninguna diferencia sistemática apreciable de las velocidades de CASLEO, siendo la media cuadrática de los residuos del orden de 1.0 km/s.

  6. [Not Available].

    PubMed

    Aguilera Eguía, Raúl; Jorquera Pino, Paula Jessica; Salgado, Claudia Jaqueline; Flores, Cherie

    2016-01-01

    Introducción: según la Organización Mundial de la Salud, la obesidad se puede definir como una acumulación anormal o excesiva de grasa que puede ser yatrogénica para la salud.Objetivo: resumir las revisiones sistemáticas Cochrane y no Cochrane que evalúen el efecto de la suplementación de calcio para la disminución del Índice de masa corporal en personas obesas.Materiales y métodos: se realizó una búsqueda en la base de datos Medline (1980 - septiembre de 2015), Metabuscador TripDatabase y Epistemonikos (hasta septiembre de 2015), Cochrane BVS (hasta septiembre de 2015); se buscó de forma manual en revistas relacionadas con el tema de interés; se buscaron actas de congresos y se realizaron seguimientos de referencias relevantes y se contactó con expertos en el área.Resultados: la búsqueda preliminar arrojó un total de 7.163 artículos potencialmente elegibles. Según los criterios de elegibilidad incluimos dos revisiones sistemáticas de estudios clínicos aleatorizados.Conclusión: el suplemento de calcio, al parecer, no incidiría en la disminución del índice de masa corporal, DM 0,12 (-0,62, 0,86); p = 0,75, presentando "muy baja evidencia" según GRADE, esto quiere decir que "presenta una gran incertidumbre sobre la estimación del efecto". PMID:27571676

  7. Assessment of hydraulic properties of sedimentary and volcanic aquifer systems under arid conditions in the Republic of Djibouti (Horn of Africa)

    NASA Astrophysics Data System (ADS)

    Jalludin, Mohamed; Razack, Moumtaz

    déduire la transmissivité. Concernant les aquifères volcaniques, la transmissivité a également été estimée à l'aide d'une relation empirique reliant la transmissivité et le débit spécifique corrigé des pertes de charge anormales. La transmissivité pour chaque aquifère couvre jusqu'à quatre ordres de grandeur, montrant la forte hétérogénéité de ces milieux. Pour les roches volcaniques, on observe que la transmissivité est d'autant meilleure que la roche est plus jeune. Leur transmissivité a ainsi diminué durant les temps géologiques. La compréhension des propriétés hydrauliques de ces aquifères complexes est à présent bien meilleure, ce qui permet d'envisager une gestion optimale de leurs ressources à l'aide de modèles numériques. La República de Yibuti (23.000 km2, 500.000 habitantes) está situada en el Cuerno de África, donde se han formado diversas unidades volcánicas-basaltos y riolitas-y rocas sedimentarias desde la expansión de los continentes acaecida al inicio de la deriva continental (hace 30 millones de años). La precipitación media anual es inferior a 150 mm. Las rocas volcánicas y sedimentarias, con dimensión inferior a 2.000 km2, constituyen acuíferos locales. Los basaltos estratificados forman un acuífero regional que se extiende a más de 9.000 km2. La multitud de datos existente ha sido almacenada desde los años 1960 en una base de datos. La transmisividad de estos acuíferos ha sido determinada mediante datos de ensayos de bombeo y una relación empírica que usa la capacidad específica corregida con las pérdidas turbulentas en el pozo. La transmisividad de estos acuíferos se comporta como una variable lognormal, hecho importante para los trabajos previstos de modelación con métodos estadísticos. La transmisividad de cada acuífero puede variar hasta en cuatro órdenes de magnitud, manifestando su gran heterogeneidad. Para los materiales volcánicos, la transmisividad es mayor cuanto más joven es

  8. Contribution of Systematic Reviews to Management Decisions

    PubMed Central

    COOK, CARLY N; POSSINGHAM, HUGH P; FULLER, RICHARD A

    2014-01-01

    Decisiones de Manejo Resumen Las revisiones sistemáticas resumen integralmente la evidencia sobre la efectividad de las intervenciones de conservación. Investigamos la contribución de las decisiones de manejo hechas por este creciente cuerpo de literatura. Identificamos 43 revisiones sistemáticas de evidencia de conservación, 23 de las cuales hicieron algunas conclusiones concretas relevantes al manejo. La mayoría de las revisiones se dirigían a intervenciones de conservación relevantes a las decisiones políticas; sólo el 35% consideraba intervenciones de manejo sobre-la-causa prácticas. La mayoría de las revisiones cubrieron solo una pequeña fracción de la amplitud geográfica y taxonómica a la que buscaban dirigirse (mediana = 13% de los países relevantes y 16% de los taxones relevantes). La probabilidad de que las revisiones tuvieran por lo menos algunas implicaciones para el manejo tendió a incrementar conforme la cobertura geográfica incrementaba y a declinar conforme aumentaba la amplitud taxonómica. Estos resultados sugieren que la amplitud de una revisión taxonómica requiere de una consideración cuidadosa. Las revisiones identificaron una media de 312 estudios primarios relevantes pero excluyeron 88% de estos por deficiencias en el diseño o fallas para coincidir con otros criterios de inclusión. Las revisiones resumieron en promedio 248 juegos de datos y 112 años de actividad de investigación, pero la probabilidad de que sus resultados tuvieran por lo menos algunas implicaciones para el manejo no incrementaron mientras la cantidad de investigación primaria resumida aumentaba. En algunos casos, las conclusiones fueron elusivas a pesar de la inclusión de cientos de conjuntos de datos y años de actividad de investigación acumulada. Las revisiones sistemáticas son una parte importante del juego de herramientas en la toma de decisiones de conservación, aunque consideramos que los beneficios de las revisiones sistemáticas podrían ser

  9. Distribution of stable isotopes in arid storms . II. A double-component model of kinematic wave flow and transport

    NASA Astrophysics Data System (ADS)

    Yakirevich, Alexander; Dody, Avraham; Adar, Eilon M.; Borisov, Viacheslav; Geyh, Mebus

    édible par rapport aux observations a été obtenu après un ajustement des paramètres par une méthode d'essais et d'erreurs. L'analyse de sensibilité et l'application du modèle ont ensuite été réalisés. Le modèle est plutôt sensible aux changements des paramètres caractérisant les zones de stockage dans les dépressions. Le modèle rend compte de l'effet de mémoire isotopique dans l'eau dans le stockage des dépressions entre les événements séquentiels de pluie. L'utilisation d'un modèle à double composante d'écoulement et de transport par onde cinématique permet un ajustement qualitatif et quantitatif adapté entre les distributions des δ18O calculées et observées dans l'écoulement de surface. Resumen Un nuevo método matemático basado en un modelo de doble componente de onda cinemática de flujo y transporte permite caracterizar la distribución isotópica dinámica de las tormentas en zonas áridas y la escorrentía. Este modelo describe el transporte y la evolución del δ18O en la lluvia, flujo superficial y escorrentía en una cuenca rocosa de clima árido con detención superficial distribuida uniformemente. El modelo se calibró numéricamente utilizando un conjunto de datos de descarga temporal y de distribución de δ18O para lluvia y escorrentía recogida en una pequeña cuenca rocosa en el Centro de Experimentación de Sede Boker, Israel. Se obtuvo un buen ajuste a los datos tras un ajuste de parámetros mediante prueba y error. Se realizó un análisis de sensibilidad que indicó que el modelo resulta ser bastante sensible a cambios en los parámetros que caracterizan las zonas de baja detención superficial. El modelo también refleja el efecto de la memoria isotópica en el agua de estas zonas de detención entre los distintos periodos de lluvias. El uso de un modelo de doble componente de onda cinemática de flujo y transporte proporciona un buen ajuste cualitativo y cuantitativo entre los datos medidos y calculados de δ18O en la

  10. Assessment of hydraulic properties of sedimentary and volcanic aquifer systems under arid conditions in the Republic of Djibouti (Horn of Africa)

    NASA Astrophysics Data System (ADS)

    Jalludin, Mohamed; Razack, Moumtaz

    déduire la transmissivité. Concernant les aquifères volcaniques, la transmissivité a également été estimée à l'aide d'une relation empirique reliant la transmissivité et le débit spécifique corrigé des pertes de charge anormales. La transmissivité pour chaque aquifère couvre jusqu'à quatre ordres de grandeur, montrant la forte hétérogénéité de ces milieux. Pour les roches volcaniques, on observe que la transmissivité est d'autant meilleure que la roche est plus jeune. Leur transmissivité a ainsi diminué durant les temps géologiques. La compréhension des propriétés hydrauliques de ces aquifères complexes est à présent bien meilleure, ce qui permet d'envisager une gestion optimale de leurs ressources à l'aide de modèles numériques. La República de Yibuti (23.000 km2, 500.000 habitantes) está situada en el Cuerno de África, donde se han formado diversas unidades volcánicas-basaltos y riolitas-y rocas sedimentarias desde la expansión de los continentes acaecida al inicio de la deriva continental (hace 30 millones de años). La precipitación media anual es inferior a 150 mm. Las rocas volcánicas y sedimentarias, con dimensión inferior a 2.000 km2, constituyen acuíferos locales. Los basaltos estratificados forman un acuífero regional que se extiende a más de 9.000 km2. La multitud de datos existente ha sido almacenada desde los años 1960 en una base de datos. La transmisividad de estos acuíferos ha sido determinada mediante datos de ensayos de bombeo y una relación empírica que usa la capacidad específica corregida con las pérdidas turbulentas en el pozo. La transmisividad de estos acuíferos se comporta como una variable lognormal, hecho importante para los trabajos previstos de modelación con métodos estadísticos. La transmisividad de cada acuífero puede variar hasta en cuatro órdenes de magnitud, manifestando su gran heterogeneidad. Para los materiales volcánicos, la transmisividad es mayor cuanto más joven es

  11. Analysis of phospholipid fatty acids (PLFA) to characterize microbial communities in aquifers

    NASA Astrophysics Data System (ADS)

    Green, Christopher T.; Scow, Kate M.

    techniques basées sur les lipides dans l'étude de la microbiologie des eaux souterraines est intéressante parce qu'elle ne nécessite pas de mise en culture et qu'elle peut fournir des données quantitatives sur les communautés dans leur ensemble. Toutefois, les effets combinés de changements physiologiques et phylogénétiques sur la composition d'une communauté peuvent brouiller l'interprétation des données de nombreuses questions se posent sur la validité des différentes techniques lipidiques. Malgré ces oppositions, la recherche basée sur les lipides a commencéà montrer des tendances dans la composition des communautés dans les aquifères pollués et dans ceux non perturbés ces résultats contribuent ainsi à notre compréhension de l'écologie microbienne des eaux souterraines et montrent qu'il existe un potentiel pour leur utilisation en vue d'une optimisation de la dépollution biologique des eaux souterraines. Resumen Se revisan distintas técnicas bioquímicas que se basan en el análisis de lípidos para caracterizar las comunidades microbianas en hábitats subsuperficiales, incluyendo acuíferos. Estas técnicas, entre las que se incluye el análisis de ácidos grasos fosfolípidos (PLFA), pueden proporcionar información sobre toda una serie de características de las comunidades microbianas, como su biomasa, fisiología, identidad taxonómica y funcional y composición. Además, el análisis estadístico multivariado de los datos de lípidos permite relacionar los cambios espaciales o temporales en las comunidades microbianas con factores ambientales. Las técnicas basadas en lípidos son muy útiles para el estudio microbiológico de las aguas subterráneas, puesto que no requieren cultivos y además proporcionan datos cuantitativos de comunidades completas. Sin embargo, la acción combinada de los cambios fisiológicos y filogenéticos en la composición de lípidos en una comunidad pueden confundir la interpretación de los datos, por lo

  12. Analysis of phospholipid fatty acids (PLFA) to characterize microbial communities in aquifers

    NASA Astrophysics Data System (ADS)

    Green, Christopher T.; Scow, Kate M.

    techniques basées sur les lipides dans l'étude de la microbiologie des eaux souterraines est intéressante parce qu'elle ne nécessite pas de mise en culture et qu'elle peut fournir des données quantitatives sur les communautés dans leur ensemble. Toutefois, les effets combinés de changements physiologiques et phylogénétiques sur la composition d'une communauté peuvent brouiller l'interprétation des données de nombreuses questions se posent sur la validité des différentes techniques lipidiques. Malgré ces oppositions, la recherche basée sur les lipides a commencéà montrer des tendances dans la composition des communautés dans les aquifères pollués et dans ceux non perturbés ces résultats contribuent ainsi à notre compréhension de l'écologie microbienne des eaux souterraines et montrent qu'il existe un potentiel pour leur utilisation en vue d'une optimisation de la dépollution biologique des eaux souterraines. Resumen Se revisan distintas técnicas bioquímicas que se basan en el análisis de lípidos para caracterizar las comunidades microbianas en hábitats subsuperficiales, incluyendo acuíferos. Estas técnicas, entre las que se incluye el análisis de ácidos grasos fosfolípidos (PLFA), pueden proporcionar información sobre toda una serie de características de las comunidades microbianas, como su biomasa, fisiología, identidad taxonómica y funcional y composición. Además, el análisis estadístico multivariado de los datos de lípidos permite relacionar los cambios espaciales o temporales en las comunidades microbianas con factores ambientales. Las técnicas basadas en lípidos son muy útiles para el estudio microbiológico de las aguas subterráneas, puesto que no requieren cultivos y además proporcionan datos cuantitativos de comunidades completas. Sin embargo, la acción combinada de los cambios fisiológicos y filogenéticos en la composición de lípidos en una comunidad pueden confundir la interpretación de los datos, por lo

  13. Mass Ejection from Old and Young Stars and the Sun

    NASA Astrophysics Data System (ADS)

    Jatenco-Pereira, V.; Opher, R.

    1990-11-01

    RESUMEN. Para poder explicar: 1) la enorme cantidad de perdida de masa y la baja velocidad asint5tica de las estrellas gigantes de o, y 2) los flujos de masa observados en protoestrellas, se sugiere un modelo para Ia perdida de masa, en donde se usa un flujo de ondas de Alfvencomo un mecanismo de aceleraci6n para los vientos de estrellas de tipo y vientos en protoestrellas. Se estudian los mecanismos de disipaci5n de las ondas de Alfven: los amortiguamientos no lineal, de superficie reso- nante y turbulento. En nuestro modelo se usa una divergente A(r) = A(R0) (r/r0)5 (donde A(r) es el area a una distancia radial r, y (A(r)/r2)max/(A(ro)/r02 - 10). Tambien se sugiere un modelo para una de hoyo coronal en el Sol. Se muestra que para satisfacer los datos observacionales en el Sol, tomando en cuenta la deposici6n del momento de las ondas de Alfven sobre el viento, se necesita: (a) una divergencia lenta en un hoyo coronal hasta una altura de 0.01 - 0.1 R seguido de (b) una divergencia rap ida de hasta una altura aproximada de 1 R . ABSTRACT: In order to explain (1) a large mass-loss rate and a small asymptotic flow speed of late-type giant stars and (2) the observed protostellar mass outflows, we suggest a model for mass loss, where we use a flux of Alfven waves as a mechanism of acceleration for late-type giant star winds and protostellar winds. We study the Alfven wave dissipation mechanisms: nonlinear damping, resonant surface damping, and turbulent damping. In our model we use a diverging geometry A(r) = A(r0) (r I r )S (where A(r) is the cross sectional area of the geometry at a radial distance r, and(A(r) I r2)max/(A(r0)/r02) = 10). We also suggest a model for a coronal hole geometry in the sun. We show that in order to satisfy the observational data of the sun, taking into account Alfven wave momentum deposition in the wind, we need: (a) a slow divergence in a coronal hole up t6 a height of 0.01 - 0.1 followed by (b) a rapid divergence up to a height of

  14. [In Process Citation].

    PubMed

    Guzmán-Mercado, Elizabeth; Vásquez-Garibay, Edgar M; Troyo-Sanroman, Rogelio; Romero-Velarde, Enrique

    2016-01-01

    Objetivo: identificar los hábitos alimentarios de adolescentes embarazadas en cuatro estados civiles diferentes: casada, cohabita con una pareja, soltera sin pareja y soltera con una pareja. Métodos: en estudio transversal, se incluyeron 321 adolescentes embarazadas de 13-19 años que acudieron al Hospital Civil de Guadalajara Dr. Juan I Menchaca, Guadalajara (Jalisco, México). Se encontraban sanas, en cualquier trimestre del embarazo y pertenecían a un nivel socioe-conómico bajo o medio-bajo. El estado civil se estratificó en: casadas; en unión libre; soltera con una pareja y soltera sin pareja. Se incluyeron datos socio-demográficos, económicos y de hábitos de alimentación. Se utilizaron pruebas de ANOVA, pruebas post-hoc para Chi 2 , razón de momios y modelos de regresión logística. Resultados: la frecuencia de las adolescentes casadas fue de 9,3%, 59,8% en unión libre, 15,3% eran solteras sin pareja y 15,6% solteras con pareja. La baja escolaridad (RM 2,6 [1,5-4,4]) y la ocupación en el hogar (RM 4,47 [1,99-10,0]) predominaron entre las adolescentes en unión libre; la ocupación en el hogar (RM 0,28 [0,127-0,61]) y cenar sin compañía (RM 4,12 [1,62-10,8]) fueron significativamente más frecuentes en adolescentes sin pareja. El consumo de verduras fue menor en las adolescentes casadas y en quienes cohabitaban con pareja; el consumo de frijoles y pan dulce fue menor en adolescentes embarazadas casadas. Conclusión: debido a que ciertas variables y hábitos de alimentación mostraron diferencias entre los grupos es pertinente analizar las adolescentes embarazadas de acuerdo a su estado civil. PMID:27238777

  15. Effect of acclimation to outdoor condition on the sexual performance of mass-produced Medflies (Diptera: Tephritidae)

    SciTech Connect

    Pereira, R.; Silva, N.; Quintal, C.; Abreu, R.; Andrade, J.; Dantas, L.

    2007-03-15

    Application of the sterile insect technique (SIT) as part of integrated area-wide programs to control the Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) require that the released males attract wild females and transfer sterile sperm. However, knowledge about male sexual performance after they are released is scarce. We conducted a study to evaluate male sexual performance in field cage tests, according to standard quality control procedures. Mass-reared 5-d-old sterile males from the genetic sexing strain VIENNA 7mix2000 were acclimated for 0, 1, and 3 d to outdoor conditions before competing with wild males for wild females. Although the proportion of mating (PM) in the test was satisfactory, the resulting relative sterility index (RSI) data showed no significant differences among the treatments. The data indicate that pre-conditioning males to outdoor conditions in Madeira did not confer an advantage in field cage sexual performance. (author) [Spanish] La aplicacion de la tecnica del insecto esteril (TIE) como parte de un programa integrado de amplio efecto para el control de la mosca mediterranea de la fruta Ceratitis capitata (Wiedemann) requiere que los machos liberados atraigan las hembras naturales y transfieran su esperma. Sin embargo, el conocimiento del desempeno sexual de los machos despues de ser liberados es muy escaso. Nosotros realizamos un estudio para evaluar el desempeno sexual de los machos en pruebas usando jaulas del campo, segun los procedimientos estandardizados de calidad. Machos esteriles de 5 dias de edad de la raza que separa los sexos geneticamente VIENNA 7mix2000 criados en masa fueron aclimatados por 0, 1 y 3 dias en condiciones de campo antes de competir con machos naturales para las hembras naturales. Aunque la proporcion del apareamiento en la prueba fue satisfactorio, el indice relativo de esterilidad (IRS) resultante no mostro ninguna diferencia significativa entre los tratamientos. Los datos indicaron que al

  16. [Not Available].

    PubMed

    MIján de la Torre, Alberto

    2016-01-01

    El síndrome de caquexia cancerosa es responsable de la muerte de un número significativo de pacientes con cáncer. Se caracteriza por la presencia de una ingesta reducida, con inflamación sistémica y un metabolismo alterado. Los enfermos presentan característicamente una progresiva pérdida de peso y de masa muscular, junto a deterioro funcional. La pérdida muscular se debe a la combinación de reducción de la síntesis proteica con aumento de su degradación. Ello conduce tanto a un acortamiento como a una reducción en el área de la fibra muscular. Asimismo, existen datos que apoyan que selectivamente algunos de los tipos de fibra muscular se ven más afectados. Es necesario definir bien los valores de corte de sarcopenia para diagnosticar la pérdida muscular y existen diferentes métodos. El sistema de la ubiquitina-proteasoma parece desempeñar un papel predominante en la degradación de la proteína miofibrilar. La tendencia a perder masa muscular en los pacientes con caquexia cancerosa parece estar asociada a la activación de señales catabólicas por citoquinas proinflamatorias, así como por productos tumorales del tipo factor inductor de proteólisis. En referencia a los factores pronósticos, el riesgo de muerte está bien documentado en pacientes con sarcopenia y, especialmente, en aquellos con obesidad asociada a la sarcopenia. Asimismo, se ha establecido una relación directa entre la pérdida intensa de masa muscular y la supervivencia en pacientes con diferentes tipos de tumores del tipo de cáncer de páncreas, pulmón, tracto biliar o cáncer colorrectal. Respecto de la terapia en el síndrome de caquexia cancerosa, es factible que requiera tratamiento con varios grupos combinados que incluyan, junto al soporte nutricional, fármacos orexígenos, con efecto anabólico y antinflamatorio, asociados a intervenciones que estimulen el ejercicio físico. PMID:27269215

  17. Influencia atmosférica en la rotación terrestre

    NASA Astrophysics Data System (ADS)

    Fernández, L. I.; Arias, E. F.; Brunini, C. A.

    Las observaciones de los parámetros de la orientación terrestre han alcanzado en estos últimos años una exactitud sin precedentes gracias al uso de modernas técnicas de geodesia espacial. Estudios previos han establecido que las variaciones en la rotación terrestre con períodos iguales o menores que dos años obedecen a cambios en la circulación atmosférica global. Para estos períodos puede comprobarse que existe un gran acuerdo entre las fluctuaciones de la longitud del día (LOD) y los cambios del momento angular atmosférico terrestre (AAM). Sin embargo, no existe un acuerdo general acerca de las causas que provocan las variaciones de largo período de la rotación de la Tierra, también conocidas como ``variaciones decenales''. En nuestro análisis examinamos las correlaciones entre las variaciones de los valores de LOD y las fluctuaciones en la componente polar del momento angular atmosférico terrestre. Con este propósito utilizamos los siguientes juegos de datos: las series de AAM, estimado siguiendo la definición de Barnes et al.(1983) para 2825 días provientes del National Meteorological Center (NMC) y del European Centre for Medium Range Weather Forecast (ECMWF); y las series de LOD que contienen valores alisados espaciados a intervalos de un día elaborados por el International Earth Rotation Service (IERS). Mostraremos que para los cambios anuales e interanuales en la rotación de la Tierra la influencia atmosférica es asombrosa, mientras que, tanto en las escalas temporales más grandes y como en las más pequeñas, ambas series, geodésica y atmosférica, parecen diverger aún cuando poseemos observaciones obtenidas con las técnicas más modernas al presente.

  18. RASTREO DEL CANCER COLORRECTAL CONOCIMIENTO Y ACTITUD DE LA POBLACION

    PubMed Central

    CASAL, ENRIQUE R.; VELAZQUEZ, ELIZABETH N.; MEJIA, RAUL M.; CUNEO, ALDO; PEREZ-STABLE, ELISEO J.

    2014-01-01

    Resumen El rastreo de cáncer colorrectal (CCR) cuenta con fuertes evidencias en su favor. Datos preliminares indican que a pesar de ello no se lleva a cabo con la frecuencia adecuada. Se intenta aquí determinar, dentro de un Sistema de Salud que cuenta con los recursos necesarios, los elementos que facilitan o generan barreras para concretar esta práctica preventiva, cuántos individuos lo ponen en práctica y qué predice esta conducta. Se realizó una encuesta telefónica a los afiliados de una Obra Social de empleados de la Universidad de Buenos Aires, de los que 132 completaron el cuestionario (tasa de respuesta 70%). Los elementos considerados facilitadores del rastreo obtuvieron respuestas afirmativas en el 64 a 97%, mientras que los que definían barreras un 11 a 27%. En este último grupo, una categoría diferenciada la constituía el miedo a los efectos adversos: 39%, y el sentimiento de vergüenza relacionado con los procedimientos: 30%. Un 33% de los encuestados tenían hecho un método de rastreo, mayoritariamente de sangre oculta (27), sigmoideoscopía (11) y colonoscopía (20). Una mayoría afirmó que “se haría el procedimiento si el médico se lo recomendara” (95%), o “no se lo haría excepto que su médico se lo aconseje” (87%). Contestar afirmativamente que “los médicos hacen lo mejor para los pacientes” se asoció con haberse hecho un método de rastreo de CCR, OR 1.55 (IC 95%: 1.02-2.37) p: 0.04. El grupo de individuos estudiado parece bien predispuesto para el rastreo del CCR, la recomendación médica sería aquí un determinante prominente para ponerlo en práctica. PMID:19414294

  19. Radioastronomía: Una Mirada Más Amplia

    NASA Astrophysics Data System (ADS)

    Bianchi, Viviana

    2004-12-01

    The existence of the celestial bodies is known due to the light they emit. But light is a small part of a bigger phenomenon known as electromagnetic radiation. The representation of all kinds of electromagnetic radiation as a function of its frequency is called the electromagnetic spectrum. If we only studied the visible part of the spectrum, we would ignore a great deal of information. The celestial bodies emit radiation in all the regions of the electromagnetic spectrum, with very different intensity. To capture these data, astronomers design new types of telescopes that capture radiation at different wavelengths, among them the radiotelescopes that, as the name indicates, detect radio waves. The radiotelescope can be compared to a regular radio set. A radio station sends information by means of radio waves. The radio set captures these waves by means of its antenna, processes it and reproduces the information (music, etc.) in audible form. In the field of radioastronomy, interesting observations can be carried out: radio emission from stars, nebulas, pulsars, distant galaxies and stars, radiogalaxies, the Milky Way, the Sun, Jupiter, etc. La presencia de los cuerpos celestes se conoce gracias a que emiten luz. Pero la luz constituye solo una pequeña parte de un fenómeno mucho mas amplio conocido como radiación electromagnética. La representación de todas las clases de radiación como función de su frecuencia se denomina espectro electromagnético. Si solo estudiáramos la parte visual del espectro ignoraríamos una gran cantidad de información. Los cuerpos celestes emiten radiación en todas las regiones del espectro electromagnético, aunque con muy distinta intensidad. Para captar estos datos, los astrónomos deben diseñar nuevos tipos de telescopios que puedan captar la radiación de distintas longitudes de ondas, entre ellos los radiotelescopios, qué como su nombre lo indica detectan ondas de radio. El radiotelescopio puede compararse a un aparato

  20. [Not Available].

    PubMed

    Molina Garrido, María José

    2016-01-01

    Cada vez es mayor el número de ancianos con diagnóstico de cáncer que acuden a las consultas de Oncología Médica. El proceso del envejecimiento y la gran variabilidad existente en la población geriátrica implican que, para hacer un abordaje adecuado del paciente, se deba considerar la edad fisiológica del anciano, y no su edad biológica. Para ello, es preciso hacer una evaluación somera, específica e individualizada a cada uno de los ancianos con diagnóstico de cáncer que acudan a nuestra consulta. La valoración geriátrica integral (VGI) es la herramienta clave que permite evaluarlos de forma adecuada, e incluso orienta la toma de decisiones "personalizada" en los ancianos con diagnóstico de cáncer. Dado que la VGI consume mucho tiempo en la consulta diaria, se están desarrollando distintas herramientas de cribado que permitan acortar la atención al paciente, al seleccionar aquellos ancianos que deban someterse a una VGI y aquellos en los que esta no sea necesaria. Se han publicado distintos modelos de VGI en la Oncogeriatría y se han desarrollado distintas herramientas de cribado de fragilidad; los más conocidos son el cuestionario Vulnerable Elders Survey-13 (VES-13) y el cuestionario G-8. En este artículo se hace una revisión acerca de la evidencia científica existente en cuanto a la atención y valoración del anciano oncológico, así como los distintos parámetros de los que se disponen para la toma de decisiones definitiva. Dichos datos reflejan el papel de la Oncogeriatría como la vía para ofrecer una atención global óptima a este grupo poblacional. PMID:27269217

  1. Forest fires and PM10 pollution: the March 2012 case in Northern Spain

    NASA Astrophysics Data System (ADS)

    Rasilla Álvarez, Domingo; García Codron, Juan Carlos; Carracedo Martín, Virginia

    2016-04-01

    Forest fires are one of the largest sources of particulate matter, carbon monoxide, volatile organic compounds and other pollutants at regional scale. They significantly impact on local air quality and human health, even far from their original sources. March 2012 was one of the largest fire activity late winter and early spring seasons across northern Spain and Portugal. Official statistics from the Spanish and Portuguese authorities show that, during that month, approximately 35.000 ha were burned, representing the top March season in Cantabria (N. Spain) and the northern distritos of Portugal since 1981, most of them occurring in the mountainous areas, as depicted from the FIRMS database (https://firms.modaps.eosdis.nasa.gov/). At the same time, an analysis of the pollution data (Airbase dataset; http://www.eea.europa.eu/) show an increase in PM10 average values and exceedences of the limit values across the same area simultaneously or immediately after the main fire activity episodes. A comprehensive analysis of this fire and pollution event was undertaken to analyze the possible contribution of forest fires and other sources of PM10 to the high levels of this pollutant at ground level. Besides statistics of fire activity, satellite "hot spots" and ground level pollution data, we have included in our analysis meteorological records (synoptic stations, upper air soundings), backtrajectories (http://ready.arl.noaa.gov/HYSPLIT.php) and dust forecast models (https://www.bsc.es/earth-sciences/mineral-dust/catalogo-datos-dust). The results show a good agreement between the spatial and temporal variability of the levels of PM10 and the direction of the pollution plumes downwind the forest fires. The activity was mostly concentrated during 3 events, the first one between February 25th to March 3rd; the second spanning from 10th to 17th, and the last one, the most severe of the three, at the end of March. The climatological background was favourable, because most of the

  2. [In Process Citation].

    PubMed

    Chacón-Cuberos, Ramón; Castro-Sánchez, Manuel; Muros-Molina, José Joaquín; Espejo-Garcés, Tamara; Zurita-Ortega, Félix; Linares-Manrique, Marta

    2016-01-01

    Introducción: la dieta mediterránea (DM) representa uno de los modelos dietéticos más completos y sanos según expresan numerosos estudios. En este sentido, la etapa universitaria supone un cambio sustancial en los hábitos alimentarios de los adultos jóvenes, alejándose de los estándares asociados a la DM. Objetivo: determinar el nivel de adherencia a la DM de un sector de población universitaria, estableciendo patrones de relación con el tipo de población en el que reside y hábitos de ocio digital asociados a videojuegos. Material y métodos: en esta investigación de diseño descriptivo y corte transversal participaron 490 estudiantes universitarios (M = 22,8 años; DT = 3,639), realizándose la recogida de datos mediante los cuestionarios KIDMED, Cuestionario de Experiencias Relacionadas con los Videojuegos (CERV) y Cuestionario sobre los Hábitos de Consumo de Videojuegos (CHCV). Resultados: más del 70% de la muestra necesitaba mejorar su alimentación y solo un 26,1% se alimentaba adecuadamente. Asimismo, los niveles de adicción a los videojuegos mostraron que un 17,8% de los participantes manifestaba problemas potenciales y un 2,7% severos. Se encontraron diferencias estadísticas en las relaciones dadas para la adhesión a la DM, la frecuencia de uso de videojuegos y el número de videojuegos jugados, concretando que los hábitos de consumo de videojuegos influyen en la adhesión a la DM en la etapa universitaria. Conclusión: ante el bajo porcentaje de universitarios que siguen una dieta de calidad óptima y su relación con el uso de videojuegos, resulta de vital importancia la creación de programas de intervención que mejoren la alimentación de este sector y disminuyan el tiempo de ocio sedentario. PMID:27238805

  3. Astronomía Gamma desde El Leoncito

    NASA Astrophysics Data System (ADS)

    Rovero, A. C.; Colombo, E.; Sahade, J.; Weekes, T. C.

    La astronomía gamma, en el extremo de energías detectadas hasta el presente, se encuentra en desarrollo en muchas partes del mundo y proporciona resultados sorprendentes a medida que la tecnología avanza en el desarrollo de nuevos detectores. La técnica Cherenkov Atmosférica es la utilizada para la detección, mediante telescopios en tierra, del efecto secundario causado por la radiación gamma de muy altas energías (E ≈ TeV). Por medio de telescopios o arreglos de detectores y utilizando la técnica mencionada, se han podido detectar algunas fuentes puntuales de mucha importancia astrofísica como la Nebulosa del Cangrejo y la galaxia de núcleo activo Markarian 421. El sistema instalado en San Juan, en cooperación con el grupo de Radiación Gamma del Observatorio Whipple, está constituído por tres colectores de 1.5m que registran pulsos de luz generados por las cascadas de partículas producidas por rayos cósmicos de todo tipo al entrar en la atmósfera terrestre. El sistema opera por barrido en ascención recta de la fuente observada que, para esta etapa del experimento, es el Centro Galáctico. Esta fuente extensa es conocida como emisor gamma de energías inferiores al TeV y ha sido observada anteriormente en este rango de energía desde el hemisferio norte pero con elevaciones bajas, situación no óptima para este tipo de técnica. Se presentan los primeros resultados del análisis de los datos obtenidos observando la región del Centro Galáctico, luego de dos años de observaciones, así como una descripción de la técnica Cherenkov Atmosférica y del equipo utilizado en la experiencia.

  4. [In Process Citation].

    PubMed

    Almeida Dos Santos, Alyne Dayana; Sabino Pinho, Cláudia Porto; Santos do Nascimento, Alexsandra Camila; Oliveira Costa, Ana Carolina

    2016-01-01

    Introducción: la sarcopenia se define como un síndrome geriátrico, multifactorial, caracterizado por la pérdida progresiva de masa muscular esquelética, asociada a consecuencias graves, tales como comorbideces, mala calidad de vida y mortandad. Objetivo: identificar la prevalencia y los factores asociados a la sarcopenia en ancianos atendidos ambulatoriamente. Métodos: estudio transversal y observacional realizado con pacientes ancianos de ambos sexos atendidos en ambulatorio geriátrico, entre junio y diciembre de 2014, en un hospital universitario ubicado en el nordeste brasileño. Se determinó la sarcopenia a través de la masa muscular (circunferencia de la pantorrilla < 31 cm), fuerza muscular (evaluada por la fuerza de prensión palmar < 30 kg para hombres y < 20 kg para mujeres) y velocidad de marcha (< 0,8 metros/segundo). Entre las variables de asociación, se consideraron aspectos socioeconómicos y demográficos, variables clínicas, estilo de vida y antropometría. La tabulación y análisis de los datos se realizaron por medio del paquete estadístico SPSS versión 13.0. Resultados: la muestra se compuso de 50 pacientes, con promedio de edad de 73,9 (± 7,4) años, en la que se verificó una prevalencia de sarcopenia del 18%. La sarcopenia fue más prevalente en individuos con edad ≥ 80 años (p = 0,012), en los ancianos con bajo peso según el IMC (p < 0,001), con desnutrición de acuerdo con la CB (p = 0,004) y en los pacientes sin hipertensión arterial (p = 0,027), no encontrándose asociación con variables socioeconómicas, clínicas y del estilo de vida. Conclusiones: la prevalencia de la sarcopenia fue significativa y semejante a la descrita por otros autores, encontrándose asociación con la edad avanzada, desnutrición y ausencia de hipertensión. PMID:27238782

  5. [Not Available].

    PubMed

    Ortega Anta, Rosa M; Jiménez Ortega, Ana Isabel; Perea Sánchez, José Miguel; Cuadrado Soto, Esther; López Sobaler, Ana M

    2016-01-01

    Objetivos: la hipertensión arterial es un problema sanitario frecuente y con repercusiones sanitarias graves, infradiagnosticado y modulado por los hábitos alimentarios, estilo de vida e ingesta de diversos nutrientes, por lo que analizar los datos más recientes sobre la implicación de la nutrición en la prevención y control de la hipertensión es el objeto de la presente revisión.Métodos: búsqueda bibliográfica en relación con el tema.Resultados: aunque las pautas más conocidas y seguidas son la restricción en la ingesta de sodio, el control de peso y la moderación en el consumo de alcohol, la mejora de la dieta (aumento en el consumo de cereales, verduras, frutas...) y la actividad física parecen tener un gran impacto en el control de las cifras de presión arterial (PA). Asimismo, un menor consumo de grasa saturada (con aumento de ácidos grasos monoinsaturados y omega-3), el aporte adecuado de calcio, magnesio, proteínas, vitamina D y fibra, y la mejora de la capacidad antioxidante de la dieta pueden tener gran importancia en la lucha contra el problema de la hipertensión. Teniendo en cuenta que la dieta media española no alcanza los aportes aconsejados para muchos de los nutrientes mencionados como favorables en el control de la PA, una aproximación de la dieta al ideal teórico puede ser de gran ayuda en la lucha contra este problema, que tiene gran impacto sanitario.Conclusiones: mejorar la alimentación, aumentando el consumo de verduras, legumbres, cereales integrales, pescado… puede tener un mayor beneficio en el control de la presión arterial que el seguimiento de pautas restrictivas más extendidas en la práctica. PMID:27571866

  6. Astronomy Teaching and Teachers Continuing Education: the Interdisciplinarity during a Total Lunar Eclipse. (Spanish Title: Enseñanza de la Astronomía y la Formación Continua de Profesores: la Interdisciplinariedad Durante un Eclipse Total de Luna.) Educação EM Astronomia E Formação Continuada de Professores: a Interdisciplinaridade Durante um Eclipse Lunar TOTAL

    NASA Astrophysics Data System (ADS)

    Langhi, Rodolfo

    2009-07-01

    This paper describes how 67 teachers from 23 cities, could awaken, in students, the scientific interest, using a natural astronomical phenomenon: a total lunar eclipse. Before and after of eclipse, meetings for continuing education were characterized by interdisciplinarity of astronomy and the importance of these observations. Working groups were formed by teachers and students, who organized the survey data, mobilizing the people in their cities. The results point ways about how to provide the scientific culture and the motivation to learn science in students, using approaches between the following communities: scientific, amateur and school. En este artículo se describe cómo 67 profesores de 23 ciudades, despertó el interés científico en los estudiantes mediante un fenómeno astronómico: un eclipse total de Luna. Antes y después del eclipse, reuniones para la formación continua se centraron en la interdisciplinariedad de la astronomía, y la importancia de las observaciones de este tipo de fenómeno. Profesores y estudiantes formaron grupos de trabajo para investigar datos durante el eclipse, con el participación de la comunidad en sus ciudades. Los resultados apuntan a las opciones que conducen a la cultura científica y la motivación para aprender la ciencia, utilizando las relaciones de los siguientes grupos: científicos, aficionados y la escuela. Este texto relata como 67 professores, provenientes de 23 cidades, puderam despertar, nos alunos, o interesse científico utilizando um fenômeno natural astronômico: um eclipse lunar total. O evento foi precedido e procedido por encontros de formação continuada, onde se caracterizou a interdisciplinaridade da astronomia e a importância das observações de fenômenos como estes. Grupos de trabalho foram formados por professores e alunos, que se organizaram para o levantamento conjunto de dados durante o fenômeno, além do envolvimento da comunidade em suas respectivas cidades. Os resultados apontam

  7. [In Process Citation].

    PubMed

    Rodríguez-Valle, Ana; Navarro-Ferrando, María Ángeles; Boj-Carceller, Diana; Escanero-Marcén, Jesús Fernando; Sanz-Paris, Alejandro

    2016-01-01

    Objetivo: poco se conoce sobre el impacto de orlistat en el sistema leptina. Estudiamos la respuesta de la leptina plasmática y la sensación de saciedad tras dos días de tratamiento con orlistat sin dieta hipocalórica ni pérdida de peso. Material y métodos: reclutamos veinte mujeres obesas en nuestras consultas externas de medicina. Habían recibido restricción dietética y modificación del estilo de vida, pero se habían mantenido obesas con peso corporal estable durante seis meses antes de su inclusión en el estudio. Resultados: las pacientes tomaron 120 mg de orlistat 3 veces al día y mantuvieron su dieta habitual. Al inicio y dos días después del tratamiento con orlistat se repitieron el examen físico, la sensación de hambre y la analítica. No hubo diferencias significativas en el consumo de energía de la dieta, el peso corporal y la relación cintura-cadera, así como en glucosa sérica, insulina y péptido C. Solamente las concentraciones de leptina y triglicéridos en suero disminuyeron (p: 0,0001 y 0,01, respectivamente). La disminución de la concentración de leptina en suero se correlacionó positivamente con cambios en la concentración de triglicéridos (p: 0.01, r2: 0,45). La sensación de hambre aumento antes de la cena y se correlacionó negativamente con la disminución de la leptina (p: 0,0001, r2: 0,74) y triglicéridos (p: 0,02, r2: 0.59). Conclusión: estos datos sugieren que la malabsorción parcial de grasas por el tratamiento con orlistat disminuye rápidamente los niveles plasmáticos de triglicéridos y leptina. Este descenso se asoció con aumento del apetito antes de la ingesta que sigue a la comida principal del día. PMID:27238788

  8. [In Process Citation].

    PubMed

    Martín Álvarez, Estefanía; Jiménez Cabanillas, María Victoria; Peña Caballero, Manuela; Serrano López, Laura; Kajarabille, Naroa; Díaz Castro, Javier; Ochoa Herrera, Julio José; Maldonado Lozano, José

    2016-01-01

    Introducción: el recién nacido prematuro de muy bajo peso (RNMBP) es inmunológicamente inmaduro y además presenta una alteración de las barreras naturales de defensa. Objetivo: evaluar los efectos que pueda tener la administración de calostro orofaríngeo, administrado durante los primeros 15 días posnatales, sobre los niveles de inmunoglobulina A (IgA) sérica en recién nacidos prematuros de muy bajo peso durante el primer mes de vida. Material y métodos: se desarrolló un estudio de intervención no aleatorizado con grupo control, en el que se incluyeron 38 recién nacidos con ≤ 32 + 6 semanas de gestación y/o menores de 1.500 g de peso. Los sujetos recibieron 0,2 ml de calostro de su madre cada 4 h, iniciándose el procedimiento en las primeras 24 h de vida hasta el 15.o día postnatal. Se midieron los niveles de IgA en la sangre al nacimiento, 3. er , 15.o y 30.o días de vida. Se registraron datos perinatales al nacimiento y durante el periodo de seguimiento. Resultados: IgA sérica aumentó de forma estadísticamente significativa en el grupo de intervención (M1 15,84 μg/ml, M2 20,07 μg/ml, M3 23,65 μg/ml, M4 30,34 μg/ml, p 0,001) y en el grupo control (M1 12,48 μg/ml, M2 16,48 μg/ml, p 0,018; M3 19,41 μg/ml, M4 22,48 μg/ml, p 0,001). Al mes de vida, los niveles de IgA sérica fueron significativamente mayores en el grupo de intervención que en el grupo control (p 0,026). Conclusiones: este estudio sugiere que la administración de calostro orofarínge. PMID:27238778

  9. [Not Available].

    PubMed

    Burgos Peláez, Rosa; Cuerda Compes, María Cristina; García-Luna, Pedro P; Martínez Faedo, Ceferino; Mauri Roca, Sílvia; Moreno Villares, José Manuel; Virgili Casas, M Nuria; Wanden-Berghe, Carmina

    2016-01-01

    Introducción:la nutrición parenteral (NP) a largo plazo puede asociarse a complicaciones graves, con un deterioro importante de la calidad de vida de los pacientes con síndrome de intestino corto (SIC). Teduglutida, un análogo del péptido-2 similar al glucagón, pertenece a una nueva familia terapéutica y representa el primer abordaje no sintomático del SIC. Objetivos: revisar los datos preclínicos y clínicos en cuanto a eficacia y seguridad de teduglutida. Resultados: la aprobación de teduglutida se basó en los resultados de un estudio en fase III de 24 semanas, doble ciego, controlado con placebo (STEPS). Pacientes con fallo intestinal por SIC dependientes de NP ≥ 3 veces/semana durante ≥ 12 meses recibieron 0,05 mg/kg de teduglutida (n = 43) o placebo (n = 43) 1 vez/día. En la semana 24 hubo significativamente más respondedores en el grupo de teduglutida que en el de placebo (63 vs.30%; p = 0,002). La reducción absoluta media del volumen de NP frente al valor basal en la semana 24 fue significativamente mayor con teduglutida (4,4 vs.2,3 l/semana; p < 0,001). La necesidad de NP se redujo ≥ 1 día en la semana 24 en el 54% de pacientes tratados con teduglutida vs.23% con placebo. Del total de pacientes que recibieron teduglutida en los ensayos en fase III (n = 134), el 12% consiguió una autonomía completa de la NP. Por lo general, la administración subcutánea de teduglutida se toleró bien. Conclusiones: se ha demostrado que teduglutida recupera la absorción intestinal y reduce significativamente la dependencia de la NP, consiguiendo incluso la independencia en algunos pacientes. PMID:27571675

  10. [Not Available].

    PubMed

    Baena González, Marta; Molina Recio, Guillermo

    2016-01-01

    Introducción: la disfagia es un síntoma que se refiere a la dificultad para mover el bolo alimentario desde la boca al estómago. A pesar de su relevancia y de la gravedad de sus posibles complicaciones, es poco conocida y estudiada. La prevalencia de la disfagia orofaríngea en enfermosde alzhéimer es de un 84% y puede originar complicaciones de gran trascendencia clínica como consecuencia de las alteraciones en la eficacia de la deglución, y en la seguridad de la misma.Objetivo: conocer el estado actual del conocimiento en relación al abordaje de la disfagia en enfermos de alzhéimer, localizando aquellos factores que permitan un diagnóstico precoz que facilite la prevención de complicaciones y la elección de la pauta de actuación más adecuada.Metodología: revisión sistemática. Estudios publicados entre 2005 y 2014 en inglés y castellano. Bases de datos: PubMed, Cochrane, Scopus, Elsevier, Scielo y Dialnet. Términos MeSH empleados: disfagia, dysphagia, alzheimer, modified y texture food.Resultados: el diagnóstico en los pacientes de alzhéimer se realiza mediante métodos clínicos y exploraciones complementarias como la videofluoroscopia, considerada como el estándar para el estudio de la disfagia orofaríngea, ya que permite identificar entre 1/3 y 1/4 de los pacientes que presentan aspiraciones silentes no diagnosticables clínicamente. Existen estrategias terapéuticas que incluyen cambios en el volumen y viscosidad del bolo, cambios posturales, maniobras deglutorias, procedimientos de rehabilitación y técnicas de incremento sensorial que han demostrado su eficacia, pero se trata de una labor compleja que exige un abordaje multidisciplinar para un correctodiagnóstico y tratamiento.Conclusiones: existe una escasa evidencia científica en el abordaje de la disfagia y un gran desconocimiento en cuanto a la alimentación de los enfermos de alzhéimer. Esta patología necesita una intervención multidisciplinar en la cual las medidas

  11. Implementacion de modulos constructivistas que atiendan "misconceptions" y lagunas conceptuales en temas de la fisica en estudiantes universitarios

    NASA Astrophysics Data System (ADS)

    Santacruz Sarmiento, Neida M.

    Este estudio se enfoco en los "misconception" y lagunas conceptuales en temas fundamentales de Fisica como son Equilibrio Termodinamico y Estatica de fluidos. En primer lugar se trabajo con la identificacion de "misconceptions" y lagunas conceptuales y se analizo en detalle la forma en que los estudiantes construyen sus propias teorias de fenomenos relacionados con los temas. Debido a la complejidad en la que los estudiantes asimilan los conceptos fisicos, se utilizo el metodo de investigacion mixto de tipo secuencial explicativo en dos etapas, una cuantitativa y otra cualitativa. La primera etapa comprendio cuatro fases: (1) Aplicacion de una prueba diagnostica para identificar el conocimiento previo y lagunas conceptuales. (2) Identificacion de "misconceptions" y lagunas del concepto a partir del conocimiento previo. (3) Implementacion de la intervencion por medio de modulos en el topico de Equilibrio Termodinamico y Estatica de Fluidos. (4) Y la realizacion de la pos prueba para analizar el impacto y la efectividad de la intervencion constructivista. En la segunda etapa se utilizo el metodo de investigacion cualitativo, por medio de una entrevista semiestructurada que partio de la elaboracion de un mapa conceptual y se finalizo con un analisis de datos conjuntamente. El desarrollo de este estudio permitio encontrar "misconceptions" y lagunas conceptuales a partir del conocimiento previo de los estudiantes participantes en los temas trabajados, que fueron atendidos en el desarrollo de las distintas actividades inquisitivas que se presentaron en el modulo constructivista. Se encontro marcadas diferencias entre la pre y pos prueba en los temas, esto se debio al requerimiento de habilidades abstractas para el tema de Estatica de Fluidos y al desarrollo intuitivo para el tema de Equilibrio Termodinamico, teniendo mejores respuestas en el segundo. Los participantes demostraron una marcada evolucion y/o cambio en sus estructuras de pensamiento, las pruebas estadisticas

  12. [In Process Citation].

    PubMed

    Santos, Carla Adriana; Fonseca, Jorge; Carolino, Elisabete; Lopes, Teresa; Sousa Guerreiro, António

    2016-01-01

    Introducción y objetivos: el cobre (Cu) es un oligoelemento muy estudiado, pero poco se sabe de su evolución en los pacientes alimentados por gastrostomía endoscópica (GEP). Pretendemos evaluar la evolución del Cu sérico desde la gastrostomía hasta 12 semanas después de la intervención en estos pacientes alimentados con preparaciones domésticas.  Métodos: realizamos un estudio observacional prospectivo para evaluar el Cu sérico, la albúmina, la transferrina y el índice de masa corporal (IMC) en el momento de la GEP, tras 4 semanas y 12 semanas después de la intervención. Los datos incluyen edad, género, NRS 2002 y enfermedad subyacente: cánceres de cabeza y cuello (CCC) y disfagia neurológica (DN). Después de la intervención, estos pacientes fueron alimentados conpreparaciones domésticas. Resultados: 146 enfermos (89 hombres), entre 21-95 años: CCC-56, DN-90. Valores de Cu entre 42-160 μg/dl (normal: 70-140 μg/dl); normales 89% (n = 130); bajos 11% (n = 16), albúmina baja: 53% (n = 77), transferrina baja: 65% (n = 94), IMC bajo: 53% (n = 78). Después de 4 semanas: valores normales de Cu en 93% y bajos en 7%, albúmina baja en 34%, transferrina baja en 52%. Tras 12 semanas: valores normales de Cu en 95% y bajos en 5%, albúmina baja en 25%, transferrina baja en 32%. No encontramos diferencias significativas en el Cusérico cuando se compara edad, género, enfermedad subyacente, IMC, albúmina y transferrina. Conclusiones: la mayoría de los enfermos presentan Cu sérico normal en el momento de la gastrostomía. Para los enfermos con Cu sérico bajo antes del procedimiento, la alimentación con preparaciones domésticas parece suficiente para su normalización progresiva. PMID:27238774

  13. [In Process Citation].

    PubMed

    Obispo Entrenas, Ana; Martín Carvajal, Francisco; Legupín Tubío, David; Lucena Navarro, Fabiola; García Caballero, Manuel; Gándara Adán, Norberto; Abilés Osinaga, Jimena

    2016-01-01

    Objetivo: el objetivo de este estudio fue evaluar la prevalencia de hipovitaminosis D en los candidatos a cirugía bariátrica (CB) y su relación con factores de riesgo y los componentes del síndrome metabólico.Material y métodos: los parámetros clínicos, antropométricos y bioquímicos se midieron en 56 pacientes caucásicos incluidos en un protocolo de cirugía bariátrica entre enero y junio de 2014. Los pacientes fueron estratificados en tres grupos de acuerdo al status de vitamina D: suficiencia (≥ 40 ng/ml), insuficiencia (40-20 ng/ml) y deficiencia (< 20 ng/ml).Resultados: se observó deficiencia de vitamina D en el 75% de los pacientes. Estos pacientes tenían mayor índice de masa corporal (p = 0,006) y concentraciones plasmáticas mas bajas de PTH (p = 0,045). Además, hubo más pacientes con diabetes mellitus tipo 2 (DM2) y dislipemia (DLPM) en el grupo con niveles de 25 (OH) D < 20 ng/ml. Asimismo la 25 (OH) D se correlacionó negativamente con la masa grasa (r = -0,504; p = 0,009), el IMC (r = -0,394; p = 0,046) y la hipertensión arterial (r = -0,637; p = 0,001).Conclusión: De nuestros hallazgos concluimos que la deficiencia de vitamina D es muy común entre los candidatos a CB y que la misma está asociada con DM2 y DLPM.Aunque hay pocos datos sobre el mejor tratamiento para el bajo nivel de vitamina D en los pacientes candidatos CB, la detección de la deficiencia de vitamina D debe realizarse de forma rutinaria en estos casos. PMID:27019241

  14. [Not Available].

    PubMed

    San Mauro Martín, Ismael; Cevallos, Vanesa; Pina Ordúñez, Diana; Garicano Vilar, Elena

    2016-01-01

    Introducción: existen alteraciones frecuentes en la alimentación de la población infantil femenina, y especialmente en atletas de deportes estéticos por la presión ejercida para mantener un cuerpo.Objetivos: evaluar los aspectos nutricionales, antropométricos y la percepción del peso de niñas que realizan gimnasia rítmica frente a un grupo control.Métodos: estudio descriptivo comparativo. Se compararon 25 niñas gimnastas con 25 niñas no gimnastas (control). Se realizó una valoración antropométrica, mediante protocolo ISAK, y nutricional, mediante un registro dietético de siete días; así como una valoración cuantitativa y cualitativa de la ingesta alimentaria, mediante el software DIAL. Se rellenó un cuestionario de hábitos y sobre la percepción de su peso corporal.Resultados: los datos antropométricos no presentaron diferencias significativas entre ambos grupos, excepto en los pliegues cutáneos y el porcentaje de grasa, el cual era estadísticamente inferior en gimnastas. La ingesta energética (1.413 ± 283 Kcal/día) de las gimnastas era inferior a la recomendada por la Food and Nutrition Board de acuerdo a su edad. La distribución de los macronutrientes cumplía con los valores normales establecidos (10-30% proteínas, 45-65% hidratos, 20-35% grasas). El 32% de las gimnastas y el 36,4% de las niñas control consideraron que les gustaría pesar menos.Conclusión: teniendo en cuenta la intensa actividad de las gimnastas, sus requerimientos energéticos deberían ajustarse a ello, ya que esto contribuirá a su desarrollo y crecimiento y a una mejor ejecución del ejercicio. En la muestra estudiada, el consumo de alimentos de las gimnastas se aleja de una alimentación equilibrada. No se observaron comportamientos diferentes en la percepción del peso entre ambos grupos. PMID:27571660

  15. [Not Available].

    PubMed

    Pérez-Flores, Juan Emmanuel; Chávez-Tostado, Mariana; Larios-Del-Toro, Youné Elizabeth; García-Rentería, Jesús; Rendrón-Félix, Jorge; Salazar-Parra, Marcela; Irusteta-Jiménez, Leire; Michel-Espinoza, Luis Rodrigo; Márquez-Valdez, Aída Rebeca; Cuesta-Márquez, Lisbeth; Álvarez-Villaseñor, Andrea Socorro; Fuentes-Orozco, Clotilde; González Ojeda, Alejandro

    2016-01-01

    Introducción: la desnutrición intrahospitalaria se ha descrito hace más de 70 años como un problema frecuente. En México se reportan cifras de entre el 20% al 50%; sin embargo no se ha estudiado su prevalencia ni su asociación con la morbilidad y mortalidad hospitalaria.Objetivos: evaluar el estado nutricional y su relación con la morbimortalidad hospitalaria en pacientes mexicanos.Métodos: cohorte prospectiva de pacientes que ingresaron en un hospital de referencia para una estancia hospitalaria mayor de 5 días. Se capturó peso, talla, índice de masa corporal (IMC), estado nutricional de acuerdo con la valoración global subjetiva (VGS) a su ingreso y egreso hospitalario, así como diagnóstico médico, complicaciones y mortalidad. Los datos fueron analizados mediante la prueba T de Student, prueba Chi-cuadrado y prueba Exacta de Fisher.Resultados: se incluyeron 610 pacientes en total, con un promedio de edad de 50,8 ± 17,32 años, 267 mujeres (43,8%) y 343 hombres (56,2%). Del total, 154 fueron catalogados con sospecha de desnutrición o desnutrición (pacientes expuestos, 25,2%) y 456 bien nutridos (pacientes no expuestos, 74,8%), con una relación de 1 a 3. La morbilidad total de la cohorte tuvo un RR = 2,70, IC 95 % (2,06-3,55) y la mortalidad con un RR = 2,64, IC 95% (1,74-4,0), siendo ambas estadísticamente significativas (p = 0,001).Conclusiones: el diagnóstico de desnutrición al ingreso hospitalario constituye un factor de riesgo para el desarrollo de complicaciones y mortalidad. Este padecimiento al ingreso en comparación con el paciente que no presenta desnutrición incrementó el riesgo de mortalidad hasta en 2.64 veces. PMID:27571661

  16. [Not Available].

    PubMed

    Germán Díaz, Marta; Moreno Villares, José Manuel; Gomis Muñoz, Pilar

    2016-01-01

    Introducción: la nutrición parenteral domiciliaria se ha convertido en un punto clave en el tratamiento de pacientes con fracaso intestinal crónico. A pesar de los importantes avances que se han producido en las últimas décadas, tanto en los accesos vasculares, como en las soluciones empleadas, las infecciones asociadas a catéter venoso central siguen constituyendo una de las complicaciones más importantes. Dentro de las estrategias para la prevención o el tratamiento de estas infecciones se encuentra el empleo de sellados con antisépticos, como el etanol o la taurolidina, o de antibióticos.Objetivo: el objetivo de este artículo es revisar la evidencia disponible sobre el empleo de sellados con antisépticos o antibióticos en el manejo de pacientes pediátricos con nutrición parenteral domiciliaria.Material y métodos: el uso de sellados con etanol o taurolidina para prevenir el desarrollo de infecciones asociadas a catéter central estaría indicado en pacientes con nutrición parenteral domiciliaria que hayan tenido más de una infección en el año anterior o que se consideren pacientes de riesgo. Los sellados con antibióticos están indicados en el tratamiento de bacteriemias asociadas a catéter central producidas por S. coagulasa-negativo o gramnegativos, asociados a un tratamiento sistémico, siempre que sea posible, con el fin de salvar el catéter. Se debería llevar a cabo la retirada del mismo cuando existan signos de infección del punto de entrada o del trayecto subcutáneo, o cuando el germen responsable de la infección sea S. aureus o Cándida.Conclusión: a pesar de que la fuerza de la evidencia sobre la eficacia del sellado en la prevención o el tratamiento de infecciones asociadas al catéter es limitada, tanto en el niño como en el adulto, cada vez existen más datos a usar esta alternativa en pacientes con nutrición parenteral domiciliaria en los que la atención y salvaguarda de los catéteres es primordial. PMID:27571647

  17. Use of IPA to demonstrate loss of forest interior birds from isolated woodlots

    USGS Publications Warehouse

    Robbins, C.S.; Boone, D.D.

    1983-01-01

    'Empleo de indices puntuales de abundancia (IPA) para demostrar la perdida de aves forestales en bosques aislados'. En Maryland, E.U., se seleccionaron bloques boscosos de diferente superficie, divididos en seis clase de tamano (2,8-6 ha, 7-14, 20-30, 34-80, 105-1300, mayores de 4000 ha). En estas ?islas' forestales fue programado un conjunto de muestreos puntuales con estas caracteristicas: 1) Cada punto se visito tres veces. 2) En cada visita se hicieron cuatro censos consecutivos de 5 minutos de duracion, empleando diferentes simbolos para machos cantores, adultos no cantores, aves en vuelo y aves inmaduras. 3) Los conteos se hicieron en tres epocas: final de Mayo, mitad de Junio y final de Junio. 4) Se dividio el tiempo de censo en tres priodos horarios: 5,15-6,30 ; 6,30-8; 8-9,30 hrs. 5) Los puntos se agruparon en co juntos de 4 a 9, considerando que un conjunto es el nlimero que un observador puede cubrir por manana. 6) La vegetacion fue descrita exhaustivamente en cuanto composicion y fisionomla. El principal objetivo que se busca consiste en conocer los requisitos areales de ciertas especies de bosque muy sensibles a la fragmentacion del habitat. Puede observarse (Figura 1) que una serie de migrantes de largo alcance se asientan en relacion con el aumento de la superficie del rodal arbo1ado, sabre todo en macizos de 4.000 o mas hectareas. Sin embargo, las especies sedentarias (Fig. 2) tienen pauta de presencia irregular en funcion del area, forestal, con tendencia a presentarse menos en los bosques mas extensos, Dryocopus pileatus, por excepcion, reacciona negativamente al pequeno tamano de la parcela arbolado, prefiriendo bosques grandes. Parecida respuesta da tambien Sitta carolinensis. Aunque se sabe poco de las exigencias areales de las aves forestales americanas, el metodo de los IPA resulta muy adecuado para esta clase de investigacion de tanto interes en gestion ambiental, posibilitando colectar gran cantidad de datos comparables en un periodo de

  18. [In Process Citation].

    PubMed

    Hernández-Morante, Juan José; Galindo-Muñoz, Joaquín Santiago; Barberá-Ortega, María Del Carmen

    2016-01-01

    Introducción: actualmente el tratamiento dietético de la obesidad no suele ser efectivo en muchos casos, probablemente porque se diseña fundamentalmente teniendo en cuenta el gasto energético mientras que otros aspectos relevantes, como los ritmos de hambre/saciedad, apenas son considerados. Los nuevos dispositivos móviles (smartphones) podrían ayudar a este respecto. Objetivo: desarrollar una aplicación para smartphones con el fin de analizar variables subjetivas relacionadas con el apetito de forma precisa y fiable.  Métodos: se analizaron las sensaciones subjetivas de apetito de 15 voluntarios sanos mediante dos métodos: papel-lápiz (P-P) y una nueva aplicación para smartphones. Las sensaciones de apetito se analizaron cada 30 minutos durante 4 horas en dos situaciones: desayuno alto en carbohidratos (HC) y alto en grasas (HF). Además, los sujetos completaron la aplicación cada 30 minutos en condiciones ambientales. Resultados: los datos derivados del ANOVA indican que no existieron diferencias respecto al método (P-P vs. aplicación) o comida (HC vs. HF) (p > 0.05) para las puntuaciones de hambre, deseo de comer y saciedad. Los coeficientes de regresión mostraron una elevada concordancia (R 2 : 0.94-0.98). El test de Bland-Altman también reveló una alta reciprocidad entre ambos métodos. Además, la aplicación fue capaz de medir las variaciones subjetivas de apetito en condiciones ambientales. Conclusión: la aplicación para smartphones fue capaz de determinar de forma fiable y precisa las variables subjetivas de apetito tanto en condiciones de laboratorio como ambientales, lo que confirma la idoneidad de esta aplicación para llevar a cabo futuros estudios en los que se evalúe la regulación del apetito en humanos. PMID:27238807

  19. Message from Vice-Chancellor

    NASA Astrophysics Data System (ADS)

    Nasir Ibrahim, Daing

    2013-12-01

    Engineering for their hardwork and relentless effort. Without their commitment and contributions, this event would not been possible and successfully delivered at this time. I wish you all a fruitful discourse. Thank you. Professor Dato' Dr Daing Nasir Ibrahim Vice-Chancellor, Universiti Malaysia Pahang

  20. Síndrome del Outlet Torácico: ¿Una Patología Siempre Quirúrgica? Análisis de una Serie de 31 Cirugías Realizadas por Vía Supraclavicular Serie clínica

    PubMed Central