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Sample records for mating-type mat loci

  1. Inversion of the chromosomal region between two mating type loci switches the mating type in Hansenula polymorpha.

    Science.gov (United States)

    Maekawa, Hiromi; Kaneko, Yoshinobu

    2014-11-01

    Yeast mating type is determined by the genotype at the mating type locus (MAT). In homothallic (self-fertile) Saccharomycotina such as Saccharomyces cerevisiae and Kluveromyces lactis, high-efficiency switching between a and α mating types enables mating. Two silent mating type cassettes, in addition to an active MAT locus, are essential components of the mating type switching mechanism. In this study, we investigated the structure and functions of mating type genes in H. polymorpha (also designated as Ogataea polymorpha). The H. polymorpha genome was found to harbor two MAT loci, MAT1 and MAT2, that are ∼18 kb apart on the same chromosome. MAT1-encoded α1 specifies α cell identity, whereas none of the mating type genes were required for a identity and mating. MAT1-encoded α2 and MAT2-encoded a1 were, however, essential for meiosis. When present in the location next to SLA2 and SUI1 genes, MAT1 or MAT2 was transcriptionally active, while the other was repressed. An inversion of the MAT intervening region was induced by nutrient limitation, resulting in the swapping of the chromosomal locations of two MAT loci, and hence switching of mating type identity. Inversion-deficient mutants exhibited severe defects only in mating with each other, suggesting that this inversion is the mechanism of mating type switching and homothallism. This chromosomal inversion-based mechanism represents a novel form of mating type switching that requires only two MAT loci.

  2. Mating-Type Genes and MAT Switching in Saccharomyces cerevisiae

    Science.gov (United States)

    Haber, James E.

    2012-01-01

    Mating type in Saccharomyces cerevisiae is determined by two nonhomologous alleles, MATa and MATα. These sequences encode regulators of the two different haploid mating types and of the diploids formed by their conjugation. Analysis of the MATa1, MATα1, and MATα2 alleles provided one of the earliest models of cell-type specification by transcriptional activators and repressors. Remarkably, homothallic yeast cells can switch their mating type as often as every generation by a highly choreographed, site-specific homologous recombination event that replaces one MAT allele with different DNA sequences encoding the opposite MAT allele. This replacement process involves the participation of two intact but unexpressed copies of mating-type information at the heterochromatic loci, HMLα and HMRa, which are located at opposite ends of the same chromosome-encoding MAT. The study of MAT switching has yielded important insights into the control of cell lineage, the silencing of gene expression, the formation of heterochromatin, and the regulation of accessibility of the donor sequences. Real-time analysis of MAT switching has provided the most detailed description of the molecular events that occur during the homologous recombinational repair of a programmed double-strand chromosome break. PMID:22555442

  3. Evolutionary Dynamics of Mating-Type Loci of Mycosphaerella spp. Occurring on Banana▿ †

    Science.gov (United States)

    Arzanlou, Mahdi; Crous, Pedro W.; Zwiers, Lute-Harm

    2010-01-01

    The devastating Sigatoka disease complex of banana is primarily caused by three closely related heterothallic fungi belonging to the genus Mycosphaerella: M. fijiensis, M. musicola, and M. eumusae. Previous phylogenetic work showing common ancestry led us to analyze the mating-type loci of these Mycosphaerella species occurring on banana. We reasoned that this might provide better insight into the evolutionary history of these species. PCR and chromosome-walking approaches were used to clone the mating-type loci of M. musicola and M. eumusae. Sequences were compared to the published mating-type loci of M. fijiensis and other Mycosphaerella spp., and a novel organization of the MAT loci was found. The mating-type loci of the examined Mycosphaerella species are expanded, containing two additional Mycosphaerella-specific genes in a unique genomic organization. The proteins encoded by these novel genes show a higher interspecies than intraspecies homology. Moreover, M. fijiensis, M. musicola, and M. eumusae contain two additional mating-type-like loci, containing parts of both MAT1-1-1 and MAT1-2-1. The data indicate that M. fijiensis, M. musicola, and M. eumusae share an ancestor in which a fusion event occurred between MAT1-1-1 and MAT1-2-1 sequences and in which additional genes became incorporated into the idiomorph. The new genes incorporated have since then evolved independently in the MAT1-1 and MAT1-2 loci. Thus, these data are an example of the evolutionary dynamics of fungal MAT loci in general and show the great flexibility of the MAT loci of Mycosphaerella species in particular. PMID:19915079

  4. Evolutionary dynamics of mating-type loci of Mycosphaerella spp. occurring on banana.

    Science.gov (United States)

    Arzanlou, Mahdi; Crous, Pedro W; Zwiers, Lute-Harm

    2010-01-01

    The devastating Sigatoka disease complex of banana is primarily caused by three closely related heterothallic fungi belonging to the genus Mycosphaerella: M. fijiensis, M. musicola, and M. eumusae. Previous phylogenetic work showing common ancestry led us to analyze the mating-type loci of these Mycosphaerella species occurring on banana. We reasoned that this might provide better insight into the evolutionary history of these species. PCR and chromosome-walking approaches were used to clone the mating-type loci of M. musicola and M. eumusae. Sequences were compared to the published mating-type loci of M. fijiensis and other Mycosphaerella spp., and a novel organization of the MAT loci was found. The mating-type loci of the examined Mycosphaerella species are expanded, containing two additional Mycosphaerella-specific genes in a unique genomic organization. The proteins encoded by these novel genes show a higher interspecies than intraspecies homology. Moreover, M. fijiensis, M. musicola, and M. eumusae contain two additional mating-type-like loci, containing parts of both MAT1-1-1 and MAT1-2-1. The data indicate that M. fijiensis, M. musicola, and M. eumusae share an ancestor in which a fusion event occurred between MAT1-1-1 and MAT1-2-1 sequences and in which additional genes became incorporated into the idiomorph. The new genes incorporated have since then evolved independently in the MAT1-1 and MAT1-2 loci. Thus, these data are an example of the evolutionary dynamics of fungal MAT loci in general and show the great flexibility of the MAT loci of Mycosphaerella species in particular.

  5. Comparative analysis of the mating-type loci from Neurospora crassa and Sordaria macrospora: identification of novel transcribed ORFs.

    Science.gov (United States)

    Pöggeler, S; Kück, U

    2000-03-01

    The mating-type locus controls mating and sexual development in filamentous ascomycetes. In the heterothallic ascomycete Neurospora crassa, the genes that confer mating behavior comprise dissimilar DNA sequences (idiomorphs) in the mat a and mat A mating partners. In the homothallic fungus Sordaria macrospora, sequences corresponding to both idiomorphs are located contiguously in the mating-type locus, which contains one chimeric gene, Smt A-3, that includes sequences which are similar to sequences found at the mat A and mat a mating-type idiomorphs in N. crassa. In this study, we describe the comparative transcriptional analysis of the chimeric mating-type region of S. macrospora and the corresponding region of the N. crassa mat a idiomorph. By means of RT-PCR experiments, we identified novel intervening sequences in the mating-type loci of both ascomycetes and, hence, concluded that an additional ORF, encoding a putative polypeptide of 79 amino acids, is present in the N. crassa mat a idiomorph. Furthermore, our analysis revealed co-transcription of the novel gene with the mat a-1 gene in N. crassa. The same mode of transcription was found in the corresponding mating-type region of S. macrospora, where the chimeric Smt A-3 gene is co-transcribed with the mat a-specific Smt a-1 gene. Analysis of a Smt A-3 cDNA revealed optional splicing of two introns. We believe that this is the first report of co-transcription of protein-encoding nuclear genes in filamentous fungi. Possible functions of the novel ORFs in regulating mating-type gene expression are discussed.

  6. The mating type-like loci of Candida glabrata.

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    Yáñez-Carrillo, Patricia; Robledo-Márquez, Karina A; Ramírez-Zavaleta, Candy Y; De Las Peñas, Alejandro; Castaño, Irene

    2014-01-01

    Candida glabrata, a haploid and opportunistic fungal pathogen that has not known sexual cycle, has conserved the majority of the genes required for mating and cell type identity. The C. glabrata genome contains three mating-type-like loci called MTL1, MTL2 and MTL3. The three loci encode putative transcription factors, a1, α1 and α2 that regulate cell type identity and sexual reproduction in other fungi like the closely related Saccharomyces cerevisiae. MTL1 can contain either a or α information. MTL2, which contains a information and MTL3 with α information, are relatively close to two telomeres. MTL1 and MTL2 are transcriptionally active, while MTL3 is subject to an incomplete silencing nucleated at the telomere that depends on the silencing proteins Sir2, Sir3, Sir4, yKu70/80, Rif1, Rap1 and Sum1. C. glabrata does not seem to maintain cell type identity, as cell type-specific genes are expressed regardless of the type (or even absence) of mating information. These data highlight important differences in the control of mating and cell type identity between the non-pathogenic yeast S. cerevisiae and C. glabrata, which might explain the absence of a sexual cycle in C. glabrata. The fact that C. glabrata has conserved the vast majority of the genes involved in mating might suggest that some of these genes perhaps have been rewired to control other processes important for the survival inside the host as a commensal or as a human pathogen. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  7. Evolutionary dynamics of mating-type loci of Mycosphaerella spp. occurring on banana

    NARCIS (Netherlands)

    Arzanlou, M.; Crous, P.W.; Zwiers, L.H.

    2010-01-01

    The devastating Sigatoka disease complex of banana is primarily caused by three closely related heterothallic fungi belonging to the genus Mycosphaerella: M. fijiensis, M. musicola, and M. eumusae. Previous phylogenetic work showing common ancestry led us to analyze the mating-type loci of these

  8. Functional characterization of MAT1-1-specific mating-type genes in the homothallic ascomycete Sordaria macrospora provides new insights into essential and nonessential sexual regulators.

    Science.gov (United States)

    Klix, V; Nowrousian, M; Ringelberg, C; Loros, J J; Dunlap, J C; Pöggeler, S

    2010-06-01

    Mating-type genes in fungi encode regulators of mating and sexual development. Heterothallic ascomycete species require different sets of mating-type genes to control nonself-recognition and mating of compatible partners of different mating types. Homothallic (self-fertile) species also carry mating-type genes in their genome that are essential for sexual development. To analyze the molecular basis of homothallism and the role of mating-type genes during fruiting-body development, we deleted each of the three genes, SmtA-1 (MAT1-1-1), SmtA-2 (MAT1-1-2), and SmtA-3 (MAT1-1-3), contained in the MAT1-1 part of the mating-type locus of the homothallic ascomycete species Sordaria macrospora. Phenotypic analysis of deletion mutants revealed that the PPF domain protein-encoding gene SmtA-2 is essential for sexual reproduction, whereas the alpha domain protein-encoding genes SmtA-1 and SmtA-3 play no role in fruiting-body development. By means of cross-species microarray analysis using Neurospora crassa oligonucleotide microarrays hybridized with S. macrospora targets and quantitative real-time PCR, we identified genes expressed under the control of SmtA-1 and SmtA-2. Both genes are involved in the regulation of gene expression, including that of pheromone genes.

  9. The Sclerotinia sclerotiorum Mating Type Locus (MAT) Contains a 3.6-kb Region That Is Inverted in Every Meiotic Generation

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    Maruthachalam, Karunakaran; Wu, Bo-Ming; Subbarao, Krishna V.

    2013-01-01

    Sclerotinia sclerotiorum is a fungal plant pathogen and the causal agent of lettuce drop, an economically important disease of California lettuce. The structure of the S. sclerotiorum mating type locus MAT has previously been reported and consists of two idiomorphs that are fused end-to-end as in other homothallics. We investigated the diversity of S. sclerotiorum MAT using a total of 283 isolates from multiple hosts and locations, and identified a novel MAT allele that differed by a 3.6-kb inversion and was designated Inv+, as opposed to the previously known S. sclerotiorum MAT that lacked the inversion and was Inv-. The inversion affected three of the four MAT genes: MAT1-2-1 and MAT1-2-4 were inverted and MAT1-1-1 was truncated at the 3’-end. Expression of MAT genes differed between Inv+ and Inv- isolates. In Inv+ isolates, only one of the three MAT1-2-1 transcript variants of Inv- isolates was detected, and the alpha1 domain of Inv+ MAT1-1-1 transcripts was truncated. Both Inv- and Inv+ isolates were self-fertile, and the inversion segregated in a 1∶1 ratio regardless of whether the parent was Inv- or Inv+. This suggested the involvement of a highly regulated process in maintaining equal proportions of Inv- and Inv+, likely associated with the sexual state. The MAT inversion region, defined as the 3.6-kb MAT inversion in Inv+ isolates and the homologous region of Inv- isolates, was flanked by a 250-bp inverted repeat on either side. The 250-bp inverted repeat was a partial MAT1-1-1 that through mediation of loop formation and crossing over, may be involved in the inversion process. Inv+ isolates were widespread, and in California and Nebraska constituted half of the isolates examined. We speculate that a similar inversion region may be involved in mating type switching in the filamentous ascomycetes Chromocrea spinulosa, Sclerotinia trifoliorum and in certain Ceratocystis species. PMID:23457637

  10. Functional Characterization of MAT1-1-Specific Mating-Type Genes in the Homothallic Ascomycete Sordaria macrospora Provides New Insights into Essential and Nonessential Sexual Regulators▿†

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    Klix, V.; Nowrousian, M.; Ringelberg, C.; Loros, J. J.; Dunlap, J. C.; Pöggeler, S.

    2010-01-01

    Mating-type genes in fungi encode regulators of mating and sexual development. Heterothallic ascomycete species require different sets of mating-type genes to control nonself-recognition and mating of compatible partners of different mating types. Homothallic (self-fertile) species also carry mating-type genes in their genome that are essential for sexual development. To analyze the molecular basis of homothallism and the role of mating-type genes during fruiting-body development, we deleted each of the three genes, SmtA-1 (MAT1-1-1), SmtA-2 (MAT1-1-2), and SmtA-3 (MAT1-1-3), contained in the MAT1-1 part of the mating-type locus of the homothallic ascomycete species Sordaria macrospora. Phenotypic analysis of deletion mutants revealed that the PPF domain protein-encoding gene SmtA-2 is essential for sexual reproduction, whereas the α domain protein-encoding genes SmtA-1 and SmtA-3 play no role in fruiting-body development. By means of cross-species microarray analysis using Neurospora crassa oligonucleotide microarrays hybridized with S. macrospora targets and quantitative real-time PCR, we identified genes expressed under the control of SmtA-1 and SmtA-2. Both genes are involved in the regulation of gene expression, including that of pheromone genes. PMID:20435701

  11. The mating type locus (MAT and sexual reproduction of Cryptococcus heveanensis: insights into the evolution of sex and sex-determining chromosomal regions in fungi.

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    Banu Metin

    2010-05-01

    Full Text Available Mating in basidiomycetous fungi is often controlled by two unlinked, multiallelic loci encoding homeodomain transcription factors or pheromones/pheromone receptors. In contrast to this tetrapolar organization, Cryptococcus neoformans/Cryptococcus gattii have a bipolar mating system, and a single biallelic locus governs sexual reproduction. The C. neoformans MAT locus is unusually large (>100 kb, contains >20 genes, and enhances virulence. Previous comparative genomic studies provided insights into how this unusual MAT locus might have evolved involving gene acquisitions into two unlinked loci and fusion into one contiguous locus, converting an ancestral tetrapolar system to a bipolar one. Here we tested this model by studying Cryptococcus heveanensis, a sister species to the pathogenic Cryptococcus species complex. An extant sexual cycle was discovered; co-incubating fertile isolates results in the teleomorph (Kwoniella heveanensis with dikaryotic hyphae, clamp connections, septate basidia, and basidiospores. To characterize the C. heveanensis MAT locus, a fosmid library was screened with C. neoformans/C. gattii MAT genes. Positive fosmids were sequenced and assembled to generate two large probably unlinked MAT gene clusters: one corresponding to the homeodomain locus and the other to the pheromone/receptor locus. Strikingly, two divergent homeodomain genes (SXI1, SXI2 are present, similar to the bE/bW Ustilago maydis paradigm, suggesting one or the other homeodomain gene was recently lost in C. neoformans/C. gattii. Sequencing MAT genes from other C. heveanensis isolates revealed a multiallelic homeodomain locus and at least a biallelic pheromone/receptor locus, similar to known tetrapolar species. Taken together, these studies reveal an extant C. heveanensis sexual cycle, define the structure of its MAT locus consistent with tetrapolar mating, and support the proposed evolutionary model for the bipolar Cryptococcus MAT locus revealing

  12. Cloning of the Lentinula edodes B mating-type locus and identification of the genetic structure controlling B mating.

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    Wu, Lin; van Peer, Arend; Song, Wenhua; Wang, Hong; Chen, Mingjie; Tan, Qi; Song, Chunyan; Zhang, Meiyan; Bao, Dapeng

    2013-12-01

    During the life cycle of heterothallic tetrapolar Agaricomycetes such as Lentinula edodes (Berk.) Pegler, the mating type system, composed of unlinked A and B loci, plays a vital role in controlling sexual development and resulting formation of the fruit body. L. edodes is produced worldwide for consumption and medicinal purposes, and understanding its sexual development is therefore of great importance. A considerable amount of mating type factors has been indicated over the past decades but few genes have actually been identified, and no complete genetic structures of L. edodes B mating-type loci are available. In this study, we cloned the matB regions from two mating compatible L. edodes strains, 939P26 and 939P42. Four pheromone receptors were identified on each new matB region, together with three and four pheromone precursor genes in the respective strains. Gene polymorphism, phylogenetic analysis and distribution of pheromone receptors and pheromone precursors clearly indicate a bipartite matB locus, each sublocus containing a pheromone receptor and one or two pheromone precursors. Detailed sequence comparisons of genetic structures between the matB regions of strains 939P42, 939P26 and a previously reported strain SUP2 further supported this model and allowed identification of the B mating type subloci borders. Mating studies confirmed the control of B mating by the identified pheromone receptors and pheromones in L. edodes. © 2013 Elsevier B.V. All rights reserved.

  13. Rapid and Efficient CRISPR/Cas9-Based Mating-Type Switching of Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Ze-Xiong Xie

    2018-01-01

    Full Text Available Rapid and highly efficient mating-type switching of Saccharomyces cerevisiae enables a wide variety of genetic manipulations, such as the construction of strains, for instance, isogenic haploid pairs of both mating-types, diploids and polyploids. We used the CRISPR/Cas9 system to generate a double-strand break at the MAT locus and, in a single cotransformation, both haploid and diploid cells were switched to the specified mating-type at ∼80% efficiency. The mating-type of strains carrying either rod or ring chromosome III were switched, including those lacking HMLα and HMRa cryptic mating loci. Furthermore, we transplanted the synthetic yeast chromosome V to build a haploid polysynthetic chromosome strain by using this method together with an endoreduplication intercross strategy. The CRISPR/Cas9 mating-type switching method will be useful in building the complete synthetic yeast (Sc2.0 genome. Importantly, it is a generally useful method to build polyploids of a defined genotype and generally expedites strain construction, for example, in the construction of fully a/a/α/α isogenic tetraploids.

  14. The smt-0 mutation which abolishes mating-type switching in fission yeast is a deletion

    DEFF Research Database (Denmark)

    Styrkársdóttir, U; Egel, R; Nielsen, O

    1993-01-01

    Mating-type switching in the fission yeast, S. pombe, is initiated by a DNA double-strand break (DSB) between the mat1 cassette and the H1 homology box. The mat1-cis-acting mutant, smt-0, abolishes mating-type switching and is shown here to be a 263-bp deletion. This deletion starts in the middle...

  15. Maintaining two mating types: structure of the mating type locus and its role in heterokaryosis in Podospora anserina.

    Science.gov (United States)

    Grognet, Pierre; Bidard, Frédérique; Kuchly, Claire; Tong, Laetitia Chan Ho; Coppin, Evelyne; Benkhali, Jinane Ait; Couloux, Arnaud; Wincker, Patrick; Debuchy, Robert; Silar, Philippe

    2014-05-01

    Pseudo-homothallism is a reproductive strategy elected by some fungi producing heterokaryotic sexual spores containing genetically different but sexually compatible nuclei. This lifestyle appears as a compromise between true homothallism (self-fertility with predominant inbreeding) and complete heterothallism (with exclusive outcrossing). However, pseudohomothallic species face the problem of maintaining heterokaryotic mycelia to fully benefit from this lifestyle, as homokaryons are self-sterile. Here, we report on the structure of chromosome 1 in mat+ and mat- isolates of strain S of the pseudohomothallic fungus Podospora anserina. Chromosome 1 contains either one of the mat+ and mat- mating types of P. anserina, which is mostly found in nature as a mat+/mat- heterokaryotic mycelium harboring sexually compatible nuclei. We identified a "mat" region ∼0.8 Mb long, devoid of meiotic recombination and containing the mating-type idiomorphs, which is a candidate to be involved in the maintenance of the heterokaryotic state, since the S mat+ and S mat- strains have different physiology that may enable hybrid-vigor-like phenomena in the heterokaryons. The mat region contains 229 coding sequences. A total of 687 polymorphisms were detected between the S mat+ and S mat- chromosomes. Importantly, the mat region is colinear between both chromosomes, which calls for an original mechanism of recombination inhibition. Microarray analyses revealed that 10% of the P. anserina genes have different transcriptional profiles in S mat+ and S mat-, in line with their different phenotypes. Finally, we show that the heterokaryotic state is faithfully maintained during mycelium growth of P. anserina, yet mat+/mat+ and mat-/mat- heterokaryons are as stable as mat+/mat- ones, evidencing a maintenance of heterokaryosis that does not rely on fitness-enhancing complementation between the S mat+ and S mat- strains.

  16. Functional analysis of mating type genes and transcriptome analysis during fruiting body development of botrytis cinerea

    NARCIS (Netherlands)

    Rodenburg, Sander Y.A.; Terhem, Razak B.; Veloso, Javier; Stassen, Joost H.M.; Kan, van Jan A.L.

    2018-01-01

    Botrytis cinerea is a plant-pathogenic fungus producing apothecia as sexual fruiting bodies. To study the function of mating type (MAT) genes, single-gene deletion mutants were generated in both genes of the MAT1-1 locus and both genes of the MAT1-2 locus. Deletion mutants in two MAT genes were

  17. Mating-type locus characterization and variation in Pyrenophora semeniperda

    Science.gov (United States)

    Julie Leanna Henry

    2015-01-01

    Pyrenophora semeniperda is a generalist fungal pathogen that occurs primarily on monocot seed hosts. It is in the phylum Ascomycota, which includes both self-compatible (homothallic) and self-incompatible (heterothallic) species. Homothallic fungal species contain complementary mating-type (MAT) idiomorphs in a single unikaryotic strain, while heterothallic strains...

  18. The fission yeast ubiquitin-conjugating enzymes UbcP3, Ubc15, and Rhp6 affect transcriptional silencing of the mating-type region

    DEFF Research Database (Denmark)

    Nielsen, Inga Sig; Nielsen, Olaf; Murray, Johanne M

    2002-01-01

    Genes transcribed by RNA polymerase II are silenced when introduced near the mat2 or mat3 mating-type loci of the fission yeast Schizosaccharomyces pombe. Silencing is mediated by a number of gene products and cis-acting elements. We report here the finding of novel trans-acting factors identified...... was not suppressed by a mutation in the 26S proteasome, suggesting that loss of silencing is not due to an increased degradation of silencing factors but rather to the posttranslational modification of proteins by ubiquitination. We discuss the implications of these results for the possible modes of action of UbcP3...

  19. Mating-type determination in Schizosaccharomyces pombe

    DEFF Research Database (Denmark)

    Ekwall, Karl; Thon, Genevieve

    2017-01-01

    Here we describe how mating-type tests are conducted in Schizosaccharomyces pombe. Two methods can be employed: matings with h− and h+ tester strains and polymerase chain reaction (PCR) for mat1 content.......Here we describe how mating-type tests are conducted in Schizosaccharomyces pombe. Two methods can be employed: matings with h− and h+ tester strains and polymerase chain reaction (PCR) for mat1 content....

  20. Mating type gene analysis in apparently asexual Cercospora species is suggestive of cryptic sex.

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    Groenewald, Marizeth; Groenewald, Johannes Z; Harrington, Thomas C; Abeln, Edwin C A; Crous, Pedro W

    2006-12-01

    The genus Cercospora consists of numerous important, apparently asexual plant pathogens. We designed degenerate primers from homologous sequences in related species to amplify part of the C. apii, C. apiicola, C. beticola, C. zeae-maydis and C. zeina mating type genes. Chromosome walking was used to determine the full length mating type genes of these species. Primers were developed to amplify and sequence homologous portions of the mating type genes of additional species. Phylogenetic analyses of these sequences revealed little variation among members of the C. apii complex, whereas C. zeae-maydis and C. zeina were found to be dissimilar. The presence of both mating types in approximately even proportions in C. beticola, C. zeae-maydis and C. zeina populations, in contrast to single mating types in C. apii (MAT1) and C. apiicola (MAT2), suggests that a sexual cycle may be active in some of these species.

  1. Mating-type genes from the homothallic fungus Sordaria macrospora are functionally expressed in a heterothallic ascomycete.

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    Pöggeler, S; Risch, S; Kück, U; Osiewacz, H D

    1997-10-01

    Homokaryons from the homothallic ascomycte Sordaria macrospora are able to enter the sexual pathway and to form fertile fruiting bodies. To analyze the molecular basis of homothallism and to elucidate the role of mating-products during fruiting body development, we cloned and sequenced the entire S. macrospora mating-type locus. Comparison of the Sordaria mating-type locus with mating-type idiomorphs from the heterothallic ascomycetes Neurospora crassa and Podospora anserina revealed that sequences from both idiomorphs (A/a and mat-/mat+, respectively) are contiguous in S. macrospora. DNA sequencing of the S. macrospora mating-type region allowed the identification of four open reading frames (ORFs), which were termed Smt-a1, SmtA-1, SmtA-2 and SmtA-3. While Smt-a1, SmtA-1, and SmtA-2 show strong sequence similarities with the corresponding N. crassa mating-type ORFs, SmtA-3 has a chimeric character. It comprises sequences that are similar to the A and a mating-type idiomorph from N. crassa. To determine functionality of the S. macrospora mating-type genes, we show that all ORFs are transcriptionally expressed. Furthermore, we transformed the S. macrospora mating-type genes into mat- and mat+ strains of the closely related heterothallic fungus P. anserina. The transformation experiments show that mating-type genes from S. macrospora induce fruiting body formation in P. anserina.

  2. Mating-type switching by chromosomal inversion in methylotrophic yeasts suggests an origin for the three-locus Saccharomyces cerevisiae system.

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    Hanson, Sara J; Byrne, Kevin P; Wolfe, Kenneth H

    2014-11-11

    Saccharomyces cerevisiae has a complex system for switching the mating type of haploid cells, requiring the genome to have three mating-type (MAT)-like loci and a mechanism for silencing two of them. How this system originated is unknown, because the three-locus system is present throughout the family Saccharomycetaceae, whereas species in the sister Candida clade have only one locus and do not switch. Here we show that yeasts in a third clade, the methylotrophs, have a simpler two-locus switching system based on reversible inversion of a section of chromosome with MATa genes at one end and MATalpha genes at the other end. In Hansenula polymorpha the 19-kb invertible region lies beside a centromere so that, depending on the orientation, either MATa or MATalpha is silenced by centromeric chromatin. In Pichia pastoris, the orientation of a 138-kb invertible region puts either MATa or MATalpha beside a telomere and represses transcription of MATa2 or MATalpha2. Both species are homothallic, and inversion of their MAT regions can be induced by crossing two strains of the same mating type. The three-locus system of S. cerevisiae, which uses a nonconservative mechanism to replace DNA at MAT, likely evolved from a conservative two-locus system that swapped genes between expression and nonexpression sites by inversion. The increasing complexity of the switching apparatus, with three loci, donor bias, and cell lineage tracking, can be explained by continuous selection to increase sporulation ability in young colonies. Our results provide an evolutionary context for the diversity of switching and silencing mechanisms.

  3. Presence and Functionality of Mating Type Genes in the Supposedly Asexual Filamentous Fungus Aspergillus oryzae

    Science.gov (United States)

    Wada, Ryuta; Maruyama, Jun-ichi; Yamaguchi, Haruka; Yamamoto, Nanase; Wagu, Yutaka; Paoletti, Mathieu; Archer, David B.; Dyer, Paul S.

    2012-01-01

    The potential for sexual reproduction in Aspergillus oryzae was assessed by investigating the presence and functionality of MAT genes. Previous genome studies had identified a MAT1-1 gene in the reference strain RIB40. We now report the existence of a complementary MAT1-2 gene and the sequencing of an idiomorphic region from A. oryzae strain AO6. This allowed the development of a PCR diagnostic assay, which detected isolates of the MAT1-1 and MAT1-2 genotypes among 180 strains assayed, including industrial tane-koji isolates. Strains used for sake and miso production showed a near-1:1 ratio of the MAT1-1 and MAT1-2 mating types, whereas strains used for soy sauce production showed a significant bias toward the MAT1-2 mating type. MAT1-1 and MAT1-2 isogenic strains were then created by genetic manipulation of the resident idiomorph, and gene expression was compared by DNA microarray and quantitative real-time PCR (qRT-PCR) methodologies under conditions in which MAT genes were expressed. Thirty-three genes were found to be upregulated more than 10-fold in either the MAT1-1 host strain or the MAT1-2 gene replacement strain relative to each other, showing that both the MAT1-1 and MAT1-2 genes functionally regulate gene expression in A. oryzae in a mating type-dependent manner, the first such report for a supposedly asexual fungus. MAT1-1 expression specifically upregulated an α-pheromone precursor gene, but the functions of most of the genes affected were unknown. The results are consistent with a heterothallic breeding system in A. oryzae, and prospects for the discovery of a sexual cycle are discussed. PMID:22327593

  4. The heterothallic sugarbeet pathogen Cercospora beticola contains exon fragments of both MAT genes that are homogenized by concerted evolution.

    Science.gov (United States)

    Bolton, Melvin D; de Jonge, Ronnie; Inderbitzin, Patrik; Liu, Zhaohui; Birla, Keshav; Van de Peer, Yves; Subbarao, Krishna V; Thomma, Bart P H J; Secor, Gary A

    2014-01-01

    Dothideomycetes is one of the most ecologically diverse and economically important classes of fungi. Sexual reproduction in this group is governed by mating type (MAT) genes at the MAT1 locus. Self-sterile (heterothallic) species contain one of two genes at MAT1 (MAT1-1-1 or MAT1-2-1) and only isolates of opposite mating type are sexually compatible. In contrast, self-fertile (homothallic) species contain both MAT genes at MAT1. Knowledge of the reproductive capacities of plant pathogens are of particular interest because recombining populations tend to be more difficult to manage in agricultural settings. In this study, we sequenced MAT1 in the heterothallic Dothideomycete fungus Cercospora beticola to gain insight into the reproductive capabilities of this important plant pathogen. In addition to the expected MAT gene at MAT1, each isolate contained fragments of both MAT1-1-1 and MAT1-2-1 at ostensibly random loci across the genome. When MAT fragments from each locus were manually assembled, they reconstituted MAT1-1-1 and MAT1-2-1 exons with high identity, suggesting a retroposition event occurred in a homothallic ancestor in which both MAT genes were fused. The genome sequences of related taxa revealed that MAT gene fragment pattern of Cercospora zeae-maydis was analogous to C. beticola. In contrast, the genome of more distantly related Mycosphaerella graminicola did not contain MAT fragments. Although fragments occurred in syntenic regions of the C. beticola and C. zeae-maydis genomes, each MAT fragment was more closely related to the intact MAT gene of the same species. Taken together, these data suggest MAT genes fragmented after divergence of M. graminicola from the remaining taxa, and concerted evolution functioned to homogenize MAT fragments and MAT genes in each species. Published by Elsevier Inc.

  5. Repression of a mating type cassette in the fission yeast by four DNA elements

    DEFF Research Database (Denmark)

    Ekwall, K; Nielsen, O; Ruusala, T

    1991-01-01

    The fission yeast, Schizosaccharomyces pombe, expresses one of two alternative mating types. They are specified by one of two determinants (M or P) present at the mat1 locus. In addition, silent copies of M and P are present on the same chromosome. In the present work we demonstrate that the diff...... partitioning in mitosis to Schizosaccharomyces pombe ars plasmids....

  6. Genomic structure and evolution of the mating type locus in the green seaweed Ulva partita.

    Science.gov (United States)

    Yamazaki, Tomokazu; Ichihara, Kensuke; Suzuki, Ryogo; Oshima, Kenshiro; Miyamura, Shinichi; Kuwano, Kazuyoshi; Toyoda, Atsushi; Suzuki, Yutaka; Sugano, Sumio; Hattori, Masahira; Kawano, Shigeyuki

    2017-09-15

    The evolution of sex chromosomes and mating loci in organisms with UV systems of sex/mating type determination in haploid phases via genes on UV chromosomes is not well understood. We report the structure of the mating type (MT) locus and its evolutionary history in the green seaweed Ulva partita, which is a multicellular organism with an isomorphic haploid-diploid life cycle and mating type determination in the haploid phase. Comprehensive comparison of a total of 12.0 and 16.6 Gb of genomic next-generation sequencing data for mt - and mt + strains identified highly rearranged MT loci of 1.0 and 1.5 Mb in size and containing 46 and 67 genes, respectively, including 23 gametologs. Molecular evolutionary analyses suggested that the MT loci diverged over a prolonged period in the individual mating types after their establishment in an ancestor. A gene encoding an RWP-RK domain-containing protein was found in the mt - MT locus but was not an ortholog of the chlorophycean mating type determination gene MID. Taken together, our results suggest that the genomic structure and its evolutionary history in the U. partita MT locus are similar to those on other UV chromosomes and that the MT locus genes are quite different from those of Chlorophyceae.

  7. Mating type genes in the genus Neofusicoccum: Mating strategies and usefulness in species delimitation.

    Science.gov (United States)

    Lopes, Anabela; Phillips, Alan J L; Alves, Artur

    2017-04-01

    The genus Neofusicoccum includes species with wide geographical and plant host distribution, some of them of economic importance. The genus currently comprises 27 species that are difficult to identify based on morphological features alone. Thus, species differentiation is based on phylogenetic species recognition using multigene genealogies. In this study, we characterised the mating type genes of Neofusicoccum species. Specific primers were designed to amplify and sequence MAT genes in several species and a PCR-based mating type diagnostic assay was developed. Homothallism was the predominant mating strategy among the species tested. Furthermore, the potential of mating type gene sequences for species delimitation was evaluated. Phylogenetic analyses were performed on both MAT genes and compared with multigene genealogies using sequences of the ribosomal internal transcribed spacer region, translation elongation factor 1-alpha and beta-tubulin. Phylogenies based on mating type genes could discriminate between the species analysed and are in concordance with the results obtained with the more conventional multilocus phylogenetic analysis approach. Thus, MAT genes represent a powerful tool to delimit cryptic species in the genus Neofusicoccum. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  8. Some evidence for skewed mating type distribution in Iranian populations of Rhynchosporium commune, the cause of barley scald disease

    Directory of Open Access Journals (Sweden)

    Arzanlou Mahdi

    2016-07-01

    Full Text Available Rhynchosporium commune (formerly known as Rhynchosporium secalis, the causal agent of scald disease on barley, is known to spread asexually by splash dispersed conidia. However, there are multiple lines of evidence for the possibility of a clandestine sexual cycle occurrence in this species including extensive genotypic diversity, equal distribution of mating type alleles across the world and expression of mating type genes. In the current study, the potential for the occurrence of a sexual cycle amongst the Iranian population of R. commune was assessed by analyzing distribution and frequency of the mating type alleles at both micro and macro-spatial scales. A total of 95 single-conidial R. commune isolates were obtained from different barley fields in Kurdistan province. Previously designed primers were applied in a multiplex PCR assay to study distribution and frequency of the mating type alleles within and between populations. Totally, 67 isolates were determined as MAT1-1 and the remaining 28 isolates as MAT1-2 throughout the sampling counties. The results obtained at a macro-spatial scale revealed that unlike Kamyaran county (both MAT1-1 and MAT1-2 at an equal ratio, an unequal distribution of mating type genes was dominant among R. commune isolates in both Mariwan and Dehgolan counties. Our findings support a predominantly asexual reproduction for Mariwan and Dehgolan counties and the possibility of sexual stage occurrence in Kamyarna county.

  9. The mating-type chromosome in the filamentous ascomycete Neurospora tetrasperma represents a model for early evolution of sex chromosomes.

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    Audrius Menkis

    2008-03-01

    Full Text Available We combined gene divergence data, classical genetics, and phylogenetics to study the evolution of the mating-type chromosome in the filamentous ascomycete Neurospora tetrasperma. In this species, a large non-recombining region of the mating-type chromosome is associated with a unique fungal life cycle where self-fertility is enforced by maintenance of a constant state of heterokaryosis. Sequence divergence between alleles of 35 genes from the two single mating-type component strains (i.e. the homokaryotic mat A or mat a-strains, derived from one N. tetrasperma heterokaryon (mat A+mat a, was analyzed. By this approach we were able to identify the boundaries and size of the non-recombining region, and reveal insight into the history of recombination cessation. The non-recombining region covers almost 7 Mbp, over 75% of the chromosome, and we hypothesize that the evolution of the mating-type chromosome in this lineage involved two successive events. The first event was contemporaneous with the split of N. tetrasperma from a common ancestor with its outcrossing relative N. crassa and suppressed recombination over at least 6.6 Mbp, and the second was confined to a smaller region in which recombination ceased more recently. In spite of the early origin of the first "evolutionary stratum", genealogies of five genes from strains belonging to an additional N. tetrasperma lineage indicate independent initiations of suppressed recombination in different phylogenetic lineages. This study highlights the shared features between the sex chromosomes found in the animal and plant kingdoms and the fungal mating-type chromosome, despite fungi having no separate sexes. As is often found in sex chromosomes of plants and animals, recombination suppression of the mating-type chromosome of N. tetrasperma involved more than one evolutionary event, covers the majority of the mating-type chromosome and is flanked by distal regions with obligate crossovers.

  10. Mixed-reproductive strategies, competitive mating-type distribution and life cycle of fourteen black morel species.

    Science.gov (United States)

    Du, Xi-Hui; Zhao, Qi; Xia, En-Hua; Gao, Li-Zhi; Richard, Franck; Yang, Zhu L

    2017-05-04

    Morchella species are well known world-round as popular and prized edible fungi due to their unique culinary flavor. Recently, several species have been successfully cultivated in China. However, their reproductive modes are still unknown, and their basic biology needs to be elucidated. Here, we use the morel genome information to investigate mating systems and life cycles of fourteen black morel species. Mating type-specific primers were developed to screen and genotype ascospores, hymenia and stipes from 223 ascocarps of the 14 species from Asia and Europe. Our data indicated that they are all heterothallic and their life cycles are predominantly haploid, but sterile haploid fruiting also exists. Ascospores in all species are mostly haploid, homokaryotic, and multinuclear, whereas aborted ascospores without any nuclei were also detected. Interestingly, we monitored divergent spatial distribution of both mating types in natural morel populations and cultivated sites, where the fertile tissue of fruiting bodies usually harbored both mating types, whereas sterile tissue of wild morels constantly had one MAT allele, while the sterile tissue of cultivated strains always exhibited both MAT alleles. Furthermore, MAT1-1-1 was detected significantly more commonly than MAT1-2-1 in natural populations, which strongly suggested a competitive advantage for MAT1-1 strains.

  11. Evidence for Sexual Reproduction: Identification, Frequency, and Spatial Distribution of Venturia effusa (Pecan Scab) Mating Type Idiomorphs.

    Science.gov (United States)

    Young, Carolyn A; Bock, Clive H; Charlton, Nikki D; Mattupalli, Chakradhar; Krom, Nick; Bowen, Joanna K; Templeton, Matthew; Plummer, Kim M; Wood, Bruce W

    2018-05-10

    Venturia effusa (syn. Fusicladium effusum), causal agent of pecan scab, is the most prevalent pathogen of pecan (Carya illinoinensis), causing severe yield losses in the southeastern United States. V. effusa is currently known only by its asexual (conidial) stage. However, the degree and distribution of genetic diversity observed within and among populations of V. effusa are typical of a sexually reproducing fungal pathogen, and comparable with other dothideomycetes with a known sexual stage, including the closely related apple scab pathogen, V. inaequalis. Using the mating type (MAT) idiomorphs from V. inaequalis, we identified a single MAT gene, MAT1-1-1, in a draft genome of V. effusa. The MAT1-1-1 locus is flanked by two conserved genes encoding a DNA lyase (APN2) and a hypothetical protein. The MAT locus spanning the flanking genes was amplified and sequenced from a subset of 14 isolates, of which 7 contained MAT1-1-1 and the remaining samples contained MAT1-2-1. A multiplex polymerase chain reaction screen was developed to amplify MAT1-1-1, MAT1-2-1, and a conserved reference gene encoding β-tubulin, and used to screen 784 monoconidial isolates of V. effusa collected from 11 populations of pecan across the southeastern United States. A hierarchical sampling protocol representing region, orchard, and tree allowed for analysis of MAT structure at different spatial scales. Analysis of this collection revealed the frequency of the MAT idiomorphs is in a 1:1 equilibrium of MAT1-1:MAT1-2. The apparent equilibrium of the MAT idiomorphs provides impetus for a renewed effort to search for the sexual stage of V. effusa. [Formula: see text] Copyright © 2018 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

  12. Fission yeast mating-type switching: programmed damage and repair

    DEFF Research Database (Denmark)

    Egel, Richard

    2005-01-01

    Mating-type switching in fission yeast follows similar rules as in budding yeast, but the underlying mechanisms are entirely different. Whilst the initiating double-strand cut in Saccharomyces cerevisiae requires recombinational repair for survival, the initial damage in Schizosaccharomyces pombe...

  13. Maintenance of sex-related genes and the co-occurrence of both mating types in Verticillium dahliae.

    Directory of Open Access Journals (Sweden)

    Dylan P G Short

    Full Text Available Verticillium dahliae is a cosmopolitan, soilborne fungus that causes a significant wilt disease on a wide variety of plant hosts including economically important crops, ornamentals, and timber species. Clonal expansion through asexual reproduction plays a vital role in recurring plant epidemics caused by this pathogen. The recent discovery of recombination between clonal lineages and preliminary investigations of the meiotic gene inventory of V. dahliae suggest that cryptic sex appears to be rare in this species. Here we expanded on previous findings on the sexual nature of V. dahliae. Only 1% of isolates in a global collection of 1120 phytopathogenic V. dahliae isolates contained the MAT1-1 idiomorph, whereas 99% contained MAT1-2. Nine unique multilocus microsatellite types comprised isolates of both mating types, eight of which were collected from the same substrate at the same time. Orthologs of 88 previously characterized sex-related genes from fungal model systems in the Ascoymycota were identified in the genome of V. dahliae, out of 93 genes investigated. Results of RT-PCR experiments using both mating types revealed that 10 arbitrarily chosen sex-related genes, including MAT1-1-1 and MAT1-2-1, were constitutively expressed in V. dahliae cultures grown under laboratory conditions. Ratios of non-synonymous (amino-acid altering to synonymous (silent substitutions in V. dahliae MAT1-1-1 and MAT1-2-1 sequences were indistinguishable from the ratios observed in the MAT genes of sexual fungi in the Pezizomycotina. Patterns consistent with strong purifying selection were also observed in 18 other arbitrarily chosen V. dahliae sex-related genes, relative to the patterns in orthologs from fungi with known sexual stages. This study builds upon recent findings from other laboratories and mounts further evidence for an ancestral or cryptic sexual stage in V. dahliae.

  14. The heterothallic sugarbeet pathogen Cercospora beticola contains exon fragments of both MAT genes that are homogenized by concerted evolution

    NARCIS (Netherlands)

    Bolton, M.D.; Jonge, de R.; Inderbitzin, P.; Liu, Z.; Birla, K.; Peer, Van de Y.; Subbarao, K.; Thomma, B.P.H.J.; Secor, G.

    2014-01-01

    Dothideomycetes is one of the most ecologically diverse and economically important classes of fungi. Sexual reproduction in this group is governed by mating type (MAT) genes at the MAT1 locus. Self-sterile (heterothallic) species contain one of two genes at MAT1 (MAT1-1-1 or MAT1-2-1) and only

  15. Sexual reproduction and mating-type-mediated strain development in the penicillin-producing fungus Penicillium chrysogenum.

    Science.gov (United States)

    Böhm, Julia; Hoff, Birgit; O'Gorman, Céline M; Wolfers, Simon; Klix, Volker; Binger, Danielle; Zadra, Ivo; Kürnsteiner, Hubert; Pöggeler, Stefanie; Dyer, Paul S; Kück, Ulrich

    2013-01-22

    Penicillium chrysogenum is a filamentous fungus of major medical and historical importance, being the original and present-day industrial source of the antibiotic penicillin. The species has been considered asexual for more than 100 y, and despite concerted efforts, it has not been possible to induce sexual reproduction, which has prevented sexual crosses being used for strain improvement. However, using knowledge of mating-type (MAT) gene organization, we now describe conditions under which a sexual cycle can be induced leading to production of meiotic ascospores. Evidence of recombination was obtained using both molecular and phenotypic markers. The identified heterothallic sexual cycle was used for strain development purposes, generating offspring with novel combinations of traits relevant to penicillin production. Furthermore, the MAT1-1-1 mating-type gene, known primarily for a role in governing sexual identity, was also found to control transcription of a wide range of genes with biotechnological relevance including those regulating penicillin production, hyphal morphology, and conidial formation. These discoveries of a sexual cycle and MAT gene function are likely to be of broad relevance for manipulation of other asexual fungi of economic importance.

  16. Evolutionary restoration of fertility in an interspecies hybrid yeast, by whole-genome duplication after a failed mating-type switch.

    Directory of Open Access Journals (Sweden)

    Raúl A Ortiz-Merino

    2017-05-01

    Full Text Available Many interspecies hybrids have been discovered in yeasts, but most of these hybrids are asexual and can replicate only mitotically. Whole-genome duplication has been proposed as a mechanism by which interspecies hybrids can regain fertility, restoring their ability to perform meiosis and sporulate. Here, we show that this process occurred naturally during the evolution of Zygosaccharomyces parabailii, an interspecies hybrid that was formed by mating between 2 parents that differed by 7% in genome sequence and by many interchromosomal rearrangements. Surprisingly, Z. parabailii has a full sexual cycle and is genetically haploid. It goes through mating-type switching and autodiploidization, followed by immediate sporulation. We identified the key evolutionary event that enabled Z. parabailii to regain fertility, which was breakage of 1 of the 2 homeologous copies of the mating-type (MAT locus in the hybrid, resulting in a chromosomal rearrangement and irreparable damage to 1 MAT locus. This rearrangement was caused by HO endonuclease, which normally functions in mating-type switching. With 1 copy of MAT inactivated, the interspecies hybrid now behaves as a haploid. Our results provide the first demonstration that MAT locus damage is a naturally occurring evolutionary mechanism for whole-genome duplication and restoration of fertility to interspecies hybrids. The events that occurred in Z. parabailii strongly resemble those postulated to have caused ancient whole-genome duplication in an ancestor of Saccharomyces cerevisiae.

  17. Tagging target genes of the mat1-2-1 transcription factor in Fusarium verticillioides (Gibberella fujikuroi MP-A)

    NARCIS (Netherlands)

    Keszthelyi, A.; Jeney, A.; Kerenyi, Z.; Mendes, O.; Waalwijk, C.; Hornok, L.

    2007-01-01

    Mating type in filamentous ascomycetes is controlled by idiomorphic alleles, named MAT1-1 and MAT1-2, which contain 1-3 genes. Of these genes MAT1-1-1 and MAT1-2-1 encode putative transcription factors and are thus considered to be the major regulators of sexual communication and mating. Fungi with

  18. Discovery of a modified tetrapolar sexual cycle in Cryptococcus amylolentus and the evolution of MAT in the Cryptococcus species complex.

    Directory of Open Access Journals (Sweden)

    Keisha Findley

    Full Text Available Sexual reproduction in fungi is governed by a specialized genomic region called the mating-type locus (MAT. The human fungal pathogenic and basidiomycetous yeast Cryptococcus neoformans has evolved a bipolar mating system (a, α in which the MAT locus is unusually large (>100 kb and encodes >20 genes including homeodomain (HD and pheromone/receptor (P/R genes. To understand how this unique bipolar mating system evolved, we investigated MAT in the closely related species Tsuchiyaea wingfieldii and Cryptococcus amylolentus and discovered two physically unlinked loci encoding the HD and P/R genes. Interestingly, the HD (B locus sex-specific region is restricted (∼2 kb and encodes two linked and divergently oriented homeodomain genes in contrast to the solo HD genes (SXI1α, SXI2a of C. neoformans and Cryptococcus gattii. The P/R (A locus contains the pheromone and pheromone receptor genes but has expanded considerably compared to other outgroup species (Cryptococcus heveanensis and is linked to many of the genes also found in the MAT locus of the pathogenic Cryptococcus species. Our discovery of a heterothallic sexual cycle for C. amylolentus allowed us to establish the biological roles of the sex-determining regions. Matings between two strains of opposite mating-types (A1B1×A2B2 produced dikaryotic hyphae with fused clamp connections, basidia, and basidiospores. Genotyping progeny using markers linked and unlinked to MAT revealed that meiosis and uniparental mitochondrial inheritance occur during the sexual cycle of C. amylolentus. The sexual cycle is tetrapolar and produces fertile progeny of four mating-types (A1B1, A1B2, A2B1, and A2B2, but a high proportion of progeny are infertile, and fertility is biased towards one parental mating-type (A1B1. Our studies reveal insights into the plasticity and transitions in both mechanisms of sex determination (bipolar versus tetrapolar and sexual reproduction (outcrossing versus inbreeding with

  19. Selecting one of several mating types through gene segment joining and deletion in Tetrahymena thermophila.

    Directory of Open Access Journals (Sweden)

    Marcella D Cervantes

    Full Text Available The unicellular eukaryote Tetrahymena thermophila has seven mating types. Cells can mate only when they recognize cells of a different mating type as non-self. As a ciliate, Tetrahymena separates its germline and soma into two nuclei. During growth the somatic nucleus is responsible for all gene transcription while the germline nucleus remains silent. During mating, a new somatic nucleus is differentiated from a germline nucleus and mating type is decided by a stochastic process. We report here that the somatic mating type locus contains a pair of genes arranged head-to-head. Each gene encodes a mating type-specific segment and a transmembrane domain that is shared by all mating types. Somatic gene knockouts showed both genes are required for efficient non-self recognition and successful mating, as assessed by pair formation and progeny production. The germline mating type locus consists of a tandem array of incomplete gene pairs representing each potential mating type. During mating, a complete new gene pair is assembled at the somatic mating type locus; the incomplete genes of one gene pair are completed by joining to gene segments at each end of germline array. All other germline gene pairs are deleted in the process. These programmed DNA rearrangements make this a fascinating system of mating type determination.

  20. Distribution of mating-type alleles and M13 PCR markers in the black leaf spot fungus Mycosphaerella fijiensis of bananas in Brazil.

    Science.gov (United States)

    Queiroz, C B; Miranda, E C; Hanada, R E; Sousa, N R; Gasparotto, L; Soares, M A; Silva, G F

    2013-02-08

    The fungus Mycosphaerella fijiensis is the causative agent of black sigatoka, which is one of the most destructive diseases of banana plants. Infection with this pathogen results in underdeveloped fruit, with no commercial value. We analyzed the distribution of the M. fijiensis mating-type system and its genetic variability using M13 phage DNA markers. We found a 1:1 distribution of mating-type alleles, indicating MAT1-1 and MAT1-2 idiomorphs. A polymorphism analysis using three different primers for M13 markers showed that only the M13 minisatellite primers generated polymorphic products. We then utilized this polymorphism to characterize 40 isolates from various Brazilian states. The largest genetic distances were found between isolates from the same location and between isolates from different parts of the country. Therefore, there was no correlation between the genetic similarity and the geographic origin of the isolates. The M13 marker was used to generate genetic fingerprints for five isolates; these fingerprints were compared with the band profiles obtained from inter-simple sequence repeat (UBC861) and inter-retrotransposon amplified polymorphism analyses. We found that the M13 marker was more effective than the other two markers for differentiating these isolates.

  1. Interaction between mating-type proteins from the homothallic fungus Sordaria macrospora.

    Science.gov (United States)

    Jacobsen, Sabine; Wittig, Michael; Pöggeler, Stefanie

    2002-06-01

    Mating-type genes control sexual development in ascomycetes. Little is known about their function in homothallic species, which are self-fertile and do not require a mating partner for sexual reproduction. The function of mating-type genes in the homothallic fungus Sordaria macrospora was assayed using a yeast system in order to find properties typical of eukaryotic transcription factors. We were able to demonstrate that the mating-type proteins SMTA-1 and SMTa-1 have domains capable of activating transcription of yeast reporter genes. Two-hybrid analysis for heterodimerization and homodimerization revealed the ability of SMTA-1 to interact with SMTa-1 and vice versa. These two proteins are encoded by different mating types in the related heterothallic species Neurospora crassa. The interaction between SMTA-1 and SMTa-1 was defined by experiments with truncated versions of SMTA-1 and in vitro by means of protein cross-linking. Moreover, we gained evidence for homodimerization of SMTA-1. Possible functions of mating-type proteins in the homothallic ascomycete S. macrospora are discussed.

  2. Genetics and Epigenetics of Mating Type Determination in Paramecium and Tetrahymena.

    Science.gov (United States)

    Orias, Eduardo; Singh, Deepankar Pratap; Meyer, Eric

    2017-09-08

    While sex is an ancient and highly conserved eukaryotic invention, self-incompatibility systems such as mating types or sexes appear to be derived limitations that show considerable evolutionary plasticity. Within a single class of ciliates, Paramecium and Tetrahymena species have long been known to present a wide variety of mating type numbers and modes of inheritance, but only recently have the genes involved been identified. Although similar transmembrane proteins mediate self/nonself recognition in both ciliates, the mechanisms of mating type determination differ widely, ranging from Mendelian systems to developmental nuclear differentiation, either stochastic or maternally inherited. The non-Mendelian systems rely on programmed editing of the germline genome that occurs during differentiation of the somatic nucleus, and they have co-opted different DNA recombination mechanisms-some previously unknown. Here we review the recent molecular advances and some remaining unsolved questions and discuss the possible implications of these diverse mechanisms for inbreeding/outbreeding balance regulation.

  3. The pat1 protein kinase controls transcription of the mating-type genes in fission yeast

    DEFF Research Database (Denmark)

    Nielsen, O; Egel, R; Nielsen, Olaf

    1990-01-01

    . This differentiation process is characterized by a transcriptional induction of the mating-type genes. Conjugation can also be induced in pat1-ts mutants by a shift to a semi-permissive temperature. The pat1 gene encodes a protein kinase, which also functions further downstream in the developmental pathway controlling...... of the mating-type genes in the zygote leads to complete loss of pat1 protein kinase activity causing entry into meiosis. Thus, pat1 can promote its own inactivation. We suggest a model according to which a stepwise inactivation of pat1 leads to sequential derepression of the processes of conjugation......The developmental programme of fission yeast brings about a transition from mitotic cell division to the dormant state of ascospores. In response to nitrogen starvation, two cells of opposite mating type conjugate to form a diploid zygote, which then undergoes meiosis and sporulation...

  4. Evolution of sexes from an ancestral mating-type specification pathway.

    Directory of Open Access Journals (Sweden)

    Sa Geng

    2014-07-01

    Full Text Available Male and female sexes have evolved repeatedly in eukaryotes but the origins of dimorphic sexes and their relationship to mating types in unicellular species are not understood. Volvocine algae include isogamous species such as Chlamydomonas reinhardtii, with two equal-sized mating types, and oogamous multicellular species such as Volvox carteri with sperm-producing males and egg-producing females. Theoretical work predicts genetic linkage of a gamete cell-size regulatory gene(s to an ancestral mating-type locus as a possible step in the evolution of dimorphic gametes, but this idea has not been tested. Here we show that, contrary to predictions, a single conserved mating locus (MT gene in volvocine algae-MID, which encodes a RWP-RK domain transcription factor-evolved from its ancestral role in C. reinhardtii as a mating-type specifier, to become a determinant of sperm and egg development in V. carteri. Transgenic female V. carteri expressing male MID produced functional sperm packets during sexual development. Transgenic male V. carteri with RNA interference (RNAi-mediated knockdowns of VcMID produced functional eggs, or self-fertile hermaphrodites. Post-transcriptional controls were found to regulate cell-type-limited expression and nuclear localization of VcMid protein that restricted its activity to nuclei of developing male germ cells and sperm. Crosses with sex-reversed strains uncoupled sex determination from sex chromosome identity and revealed gender-specific roles for male and female mating locus genes in sexual development, gamete fitness and reproductive success. Our data show genetic continuity between the mating-type specification and sex determination pathways of volvocine algae, and reveal evidence for gender-specific adaptations in the male and female mating locus haplotypes of Volvox. These findings will enable a deeper understanding of how a master regulator of mating-type determination in an ancestral unicellular species was

  5. Mating type gene analysis in apparently asexual Cercospora species is suggestive of cryptic sex

    NARCIS (Netherlands)

    Groenewald, M.; Groenewald, J.Z.; Harrington, T.C.; Abeln, E.C.A.; Crous, P.W.

    2006-01-01

    The genus Cercospora consists of numerous important, apparently asexual plant pathogens. We designed degenerate primers from homologous sequences in related species to amplify part of the C. apii, C. apiicola, C. beticola, C. zeae-maydis and C. zeina mating type genes. Chromosome walking was used to

  6. Synteny in toxigenic Fusarium species: the fumonisin gene cluster and the mating type region as examples

    NARCIS (Netherlands)

    Waalwijk, C.; Lee, van der T.A.J.; Vries, de P.M.; Hesselink, T.; Arts, J.; Kema, G.H.J.

    2004-01-01

    A comparative genomic approach was used to study the mating type locus and the gene cluster involved in toxin production ( fumonisin) in Fusarium proliferatum, a pathogen with a wide host range and a complex toxin profile. A BAC library, generated from F. proliferatum isolate ITEM 2287, was used to

  7. Cloning and analysis of the mating type idiomorphs from the barley pathogen Septoria passerinii

    NARCIS (Netherlands)

    Goodwin, S.B.; Cavaletto, J.R.; Zhang, G.; Waalwijk, C.; Kema, G.H.J.

    2003-01-01

    The genus Septoria contains more than 1000 species of plant pathogenic fungi, most of which have no known sexual stage. Species of Septoria without a known sexual stage could be recent derivatives of sexual species that have lost the ability to mate. To test this hypothesis, the mating-type region

  8. Talking Mats

    DEFF Research Database (Denmark)

    2012-01-01

    Talking Mats are visualizations in the handy size of a set of cards used to support interviews with people with mental disabilities.......Talking Mats are visualizations in the handy size of a set of cards used to support interviews with people with mental disabilities....

  9. Characterization of Phytophthora infestans populations in Colombia: first report of the A2 mating type.

    Science.gov (United States)

    Vargas, Angela M; Quesada Ocampo, Lina M; Céspedes, Maria Catalina; Carreño, Natalia; González, Adriana; Rojas, Alejandro; Zuluaga, A Paola; Myers, Kevin; Fry, William E; Jiménez, Pedro; Bernal, Adriana J; Restrepo, Silvia

    2009-01-01

    Phytophthora infestans, the causal agent of late blight in crops of the Solanaceae family, is one of the most important plant pathogens in Colombia. Not only are Solanum lycopersicum, and S. tuberosum at risk, but also several other solanaceous hosts (Physalis peruviana, S. betaceum, S. phureja, and S. quitoense) that have recently gained importance as new crops in Colombia may be at risk. Because little is known about the population structure of Phytophthora infestans in Colombia, we report here the phenotypic and molecular characterization of 97 isolates collected from these six different solanaceous plants in Colombia. All the isolates were analyzed for mating type, mitochondrial haplotypes, genotype for several microsatellites, and sequence of the internal transcribed spacer (ITS) region. This characterization identified a single individual of A2 mating type (from Physalis peruviana) for the first time in Colombia. All isolates had an ITS sequence that was at least 97% identical to the consensus sequence. Of the 97 isolates, 96 were mitochondrial haplotype IIa, with the single A2 isolate being Ia. All isolates were invariant for the microsatellites. Additionally, isolates collected from S. tuberosum and P. peruviana (64 isolates) were tested for: aggressiveness on both hosts, genotype for the isozymes (glucose-6-phosphate isomerase and peptidase), and restriction fragment length polymorphism fingerprint pattern as detected by RG57. Isolates from S. tuberosum were preferentially pathogenic on S. tuberosum, and isolates from P. peruviana were preferentially pathogenic on P. peruviana. The population from these two hosts was dominated by a single clonal lineage (59 of 64 individuals assayed), previously identified from Ecuador and Peru as EC-1. This lineage was mating type A1, IIa for mitochondrial DNA, invariant for two microsatellites, and invariant for both isozymes. The remaining four A1 isolates were in lineages very closely related to EC-1 (named EC-1.1, CO

  10. Mutations of the a mating-type gene in Neurospora crassa

    International Nuclear Information System (INIS)

    Griffiths, A.J.F.; DeLange, A.M.

    1978-01-01

    In Neurospora, the mating-type locus controls both mating (A + a is fertile) and heterokaryosis (A + a is incompatible). The two alleles appear stable: no novel fertility reactions have ever beeen reported, and attempts to separate fertility and heterokaryon incompatibility functions by recombination have been unsuccessful. In the present approach the locus was studied through a mutational analysis of heterokaryon incompatibility function. A selection system was used that detects vigorous (A + a) heterokaryotic colonies against a background of inhibited growth. Twenty-five mutants of an a strain were produced following mutagenic treatment with uv and NG: 15 were viable as homokaryons and 10 were not. All but one were infertile, but most showed an abortive mating reaction involving the production of barren, well-developed perithecia with A and (surprisingly) a testers. None of the mutants complement each other to restore fertility. Seven mutants have been mapped to the mating-type locus region of chromosome 1. Restoration of fertility was used to detect revertants, and these were found in five out of the eight mutants tested. (A dose response was observed). In four cases incompatibility was fully restored and in one case it was not. The results suggest two positive actions of the locus when in heterozygous (A/a) combination (the stimulation of some stage of ascus production and the inhibition of vegetative heterokaryosis), and one positive action in homozygous combinations

  11. Evaluation of mating type distribution and genetic diversity of three Magnaporthe oryzae avirulence genes, PWL-2, AVR-Pii and Avr-Piz-t, in Thailand rice blast isolates

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    Thanyaluk Sirisathaworn

    2017-02-01

    Full Text Available Rice blast disease, caused by the filamentous ascomycete fungus Magnaporthe oryzae (anamorph Pyricularia oryzae, has been ranked among the most important diseases of rice. The molecular mechanisms against this fungus follow the idea of “gene-for-gene interaction”, in which a plant resistance (R gene product recognizes a fungal avirulence (Avr effector and triggers the defense response. However, the Avr genes have been shown to be rapidly evolving resulting in high levels of genetic diversity. This study investigated genetic diversity that is influenced by sexual recombination and mutation for the adaptation of rice blast fungus to overcome the defense response. Mating type distribution and the nucleotide sequence variation of three avirulence genes were evaluated—PWL-2, Avr-Pii and Avr-Piz-t. In total, 77 rice blast isolates collected from infected rice plants in northern, northeastern and central Thailand in 2005, 2010 and 2012, were used in the analysis with mating type and avirulence gene-specific primers. The results revealed that all the tested blast isolates belonged to the mating type MAT1-2, suggesting a lack of sexual recombination within the population. The successful rates of PWL-2, Avr-Pii and Avr-Piz-t gene-specific primer amplification were 100%, 60% and 54%, respectively. Base substitution mutation was observed in coding regions of the Avr-Pii and Avr-Piz-t genes. Although these results showed a low level of genetic diversity in Thai rice blast isolates, non-synonymous mutations did occur which revealed common mechanisms of selective pressure that are prone to adaptation of Avr genes. The information on nucleotide sequence variation and the genetic diversity of Avr genes obtained from this study could be useful for planning novel strategies in the development of rice breeding programs in Thailand.

  12. The Hos2 Histone Deacetylase Controls Ustilago maydis Virulence through Direct Regulation of Mating-Type Genes.

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    Alberto Elías-Villalobos

    2015-08-01

    Full Text Available Morphological changes are critical for host colonisation in plant pathogenic fungi. These changes occur at specific stages of their pathogenic cycle in response to environmental signals and are mediated by transcription factors, which act as master regulators. Histone deacetylases (HDACs play crucial roles in regulating gene expression, for example by locally modulating the accessibility of chromatin to transcriptional regulators. It has been reported that HDACs play important roles in the virulence of plant fungi. However, the specific environment-sensing pathways that control fungal virulence via HDACs remain poorly characterised. Here we address this question using the maize pathogen Ustilago maydis. We find that the HDAC Hos2 is required for the dimorphic switch and pathogenic development in U. maydis. The deletion of hos2 abolishes the cAMP-dependent expression of mating type genes. Moreover, ChIP experiments detect Hos2 binding to the gene bodies of mating-type genes, which increases in proportion to their expression level following cAMP addition. These observations suggest that Hos2 acts as a downstream component of the cAMP-PKA pathway to control the expression of mating-type genes. Interestingly, we found that Clr3, another HDAC present in U. maydis, also contributes to the cAMP-dependent regulation of mating-type gene expression, demonstrating that Hos2 is not the only HDAC involved in this control system. Overall, our results provide new insights into the role of HDACs in fungal phytopathogenesis.

  13. Mating type regulates the radiation-associated stimulation of reciprocal translocation events in Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Fasullo, M.; Dave, P.

    1994-01-01

    Both ultraviolet (UV) and ionizing radiation were observed to stimulate mitotic, ectopic recombination between his3 recombinational substrates, generating reciprocal translocations in Saccharomyces cervisiae (yeast). The stimulation was greatest in diploid strains competent for sporulation and depends upon both the ploidy of the strain and heterozygosity at the MATlocus. The difference in levels of stimulation between MATa/MATalpha diploid and MATalpha haploid strains increases when cells are exposed to higher levels of UV radiation (sevenfold at 150 J/square metre), whereas when cells are exposed to higher levels of ionizing radiation (23.4 krad), only a twofold difference is observed. When the MATalpha gene was introduced by DNA transformation into a MATa/matalpha: LEU2 + diploid, the levels of radiation-induced ectopic recombination approach those obtained in a strain that is heterozygous at MAT. Conversely, when the MATa gene was introduced by DNA transformation into a MATalpha haploid, no enhanced stimulation of ectopic recombination was observed when cells were irradiated with ionizing radiation but a threefold enhancement was observed when cells were irradiated with UV. The increase in radiation stimulated ectopic recombination resulting from heterozygosity at MAT correlated with greater spontaneous ectopic recombination and higher levels of viability after irradiation. It is suggested that MAT functions that have been previously shown to control the level of mitotic, allelic recombination (homolog recombination) also control the level of mitotic, radiation-stimulated ectopic recombination between short dispersed repetitive sequences on non-homologous chromosomes

  14. Genetic Variation and Its Reflection on Posttranslational Modifications in Frequency Clock and Mating Type a-1 Proteins in Sordaria fimicola

    OpenAIRE

    Arif, Rabia; Akram, Faiza; Jamil, Tazeen; Mukhtar, Hamid; Lee, Siu Fai; Saleem, Muhammad

    2017-01-01

    Posttranslational modifications (PTMs) occur in all essential proteins taking command of their functions. There are many domains inside proteins where modifications take place on side-chains of amino acids through various enzymes to generate different species of proteins. In this manuscript we have, for the first time, predicted posttranslational modifications of frequency clock and mating type a-1 proteins in Sordaria fimicola collected from different sites to see the effect of environment o...

  15. Genetic Variation and Its Reflection on Posttranslational Modifications in Frequency Clock and Mating Type a-1 Proteins in Sordaria fimicola

    Directory of Open Access Journals (Sweden)

    Rabia Arif

    2017-01-01

    Full Text Available Posttranslational modifications (PTMs occur in all essential proteins taking command of their functions. There are many domains inside proteins where modifications take place on side-chains of amino acids through various enzymes to generate different species of proteins. In this manuscript we have, for the first time, predicted posttranslational modifications of frequency clock and mating type a-1 proteins in Sordaria fimicola collected from different sites to see the effect of environment on proteins or various amino acids pickings and their ultimate impact on consensus sequences present in mating type proteins using bioinformatics tools. Furthermore, we have also measured and walked through genomic DNA of various Sordaria strains to determine genetic diversity by genotyping the short sequence repeats (SSRs of wild strains of S. fimicola collected from contrasting environments of two opposing slopes (harsh and xeric south facing slope and mild north facing slope of Evolution Canyon (EC, Israel. Based on the whole genome sequence of S. macrospora, we targeted 20 genomic regions in S. fimicola which contain short sequence repeats (SSRs. Our data revealed genetic variations in strains from south facing slope and these findings assist in the hypothesis that genetic variations caused by stressful environments lead to evolution.

  16. Genetic Variation and Its Reflection on Posttranslational Modifications in Frequency Clock and Mating Type a-1 Proteins in Sordaria fimicola.

    Science.gov (United States)

    Arif, Rabia; Akram, Faiza; Jamil, Tazeen; Mukhtar, Hamid; Lee, Siu Fai; Saleem, Muhammad

    2017-01-01

    Posttranslational modifications (PTMs) occur in all essential proteins taking command of their functions. There are many domains inside proteins where modifications take place on side-chains of amino acids through various enzymes to generate different species of proteins. In this manuscript we have, for the first time, predicted posttranslational modifications of frequency clock and mating type a-1 proteins in Sordaria fimicola collected from different sites to see the effect of environment on proteins or various amino acids pickings and their ultimate impact on consensus sequences present in mating type proteins using bioinformatics tools. Furthermore, we have also measured and walked through genomic DNA of various Sordaria strains to determine genetic diversity by genotyping the short sequence repeats (SSRs) of wild strains of S. fimicola collected from contrasting environments of two opposing slopes (harsh and xeric south facing slope and mild north facing slope) of Evolution Canyon (EC), Israel. Based on the whole genome sequence of S. macrospora , we targeted 20 genomic regions in S. fimicola which contain short sequence repeats (SSRs). Our data revealed genetic variations in strains from south facing slope and these findings assist in the hypothesis that genetic variations caused by stressful environments lead to evolution.

  17. The transcription factor Rbf1 is the master regulator for b-mating type controlled pathogenic development in Ustilago maydis.

    Directory of Open Access Journals (Sweden)

    Kai Heimel

    Full Text Available In the phytopathogenic basidiomycete Ustilago maydis, sexual and pathogenic development are tightly connected and controlled by the heterodimeric bE/bW transcription factor complex encoded by the b-mating type locus. The formation of the active bE/bW heterodimer leads to the formation of filaments, induces a G2 cell cycle arrest, and triggers pathogenicity. Here, we identify a set of 345 bE/bW responsive genes which show altered expression during these developmental changes; several of these genes are associated with cell cycle coordination, morphogenesis and pathogenicity. 90% of the genes that show altered expression upon bE/bW-activation require the zinc finger transcription factor Rbf1, one of the few factors directly regulated by the bE/bW heterodimer. Rbf1 is a novel master regulator in a multilayered network of transcription factors that facilitates the complex regulatory traits of sexual and pathogenic development.

  18. Serotype, mating type and ploidy of Cryptococcus neoformans strains isolated from patients in Brazil Sorotipos, "mating type" e ploidia de amostras de C. neoformans isoladas de pacientes no Brasil

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    Misako OHKUSU

    2002-12-01

    Full Text Available Serotype, mating type and ploidy of 84 strains of Cryptococcus neoformans isolated from 61 AIDS and 23 non-AIDS patients admitted in a tertiary teaching hospital in São Paulo, Brazil were examined. Among 61 strains isolated from AIDS patients, 60 strains were var. grubii (serotype A. Only one strain was var. gattii (serotype B. No var. neoformans (serotype D was found. Among 23 strains isolated from non-AIDS patients, 15 were var. grubii (serotype A and the remaining 8 were var. gattii, all of which were serotype B. Seventy-three of the 75 serotype A strains were the heterothallic alpha type (MATalpha and the remaining 2 were untypable (asexual. Most of the MATalpha strains (69/73 were haploid and the remaining 4 strains were diploid. Similarly, both of the 2 asexual strains among the 75 serotype A strains were haploid. There were no alpha-mating type (MATalpha strains among the 84 isolates. All of the 8 var. gattii strains were serotype B and haploid. Among a total of 84 strains tested, neither serotype AD nor serotype D were found. Neither triploid nor tetraploid were found. These results suggest that the serological, sexual and ploidy characteristics in C. neoformans strains isolated from AIDS patients in São Paulo were rather simple, whereas strains isolated from non-AIDS patients presented serotype A and B with predominance of serotype A.Foram estudados os sorotipos, "mating type" e ploidia de 84 amostras de C. neoformans isoladas de 61 pacientes com AIDS e 23 não-AIDS em São Paulo. Das amostras isoladas de pacientes com AIDS, 60 foram identificadas como var. grubii (sorotipo A e 1 como var. gattii (sorotipo B. Não houve isolamento do sorotipo D. Entre as amostras isoladas, de pacientes não-AIDS, 15 foram de var. grubii (sorotipo A e as 8 restantes de var. gattii, todos do sorotipo B. Setenta e três dos 75 sorotipos A foram identificadas como cepas heterotálicas do fenótipo alfa (MATalfa e as 2 remanescentes n

  19. MAT FOR LEPTOSPIROSIS DIAGNOSIS

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    Esti Rahardianingtyas.

    2014-06-01

    Full Text Available Leptospirosis is a disease caused by bacterial infection leptospira interrogans.Leptospira bacteria is a spiral bacterium with solid strands with two flagella periplasmik.Septicaemic phase patient samples taken from the blood and cerebrospinal fluid, whereassamples taken at phase immune extracted from urine. The diagnosis of leptospirosis occurdirectly or indirectly. Diagnosis is done by directly isolate and identify the causative agents ofthe agent. Diagnosis is done indirectly by detecting specific antibodies from the patient's body.Gold Standard of the diagnosis of leptospirosis is MAT. Mat made by reacting antibodies toleptospira antigen. Positive results seen with clump formed.Key words: Leptospirosis, Leptospirosis Diagnostic, MAT (Microscopic Agglutination Test Leptospirosis merupakan penyakit yang disebabkan karena infeksi bakteri leptospirainterrogans. Bakteri leptospira merupakan bakteri spiral dengan untaian yang padat dengan duaflagella periplasmik. Sampel pasien pada fase septicaemic diambil dari darah dan cairanserebrospinal, sedangkan sampel yang diambil pada fase immune diambil dari urine. Diagnosisleptospirosis dilakukan secara langsung maupun tidak langsung. Diagnosis secara langsungdilakukan dengan cara mengisolasi agen penyebab dan mengidentifikasi agen tersebut. Diagnosissecara tidak langsung dilakukan dengan cara mendeteksi antibodi spesiflk dari dalam tubuhpasien. Gold Standart dari diagnosis leptospirosis adalah MAT. Mat dilakukan dengan caramereaksikan antibodi dengan antigen leptospira. Hasil positif dilihat dengan terbentuk gumpalanagglutinasiKata kunci: Leptospirosis, Leptospira, Leptospirosis Diagnosis.

  20. Genotyping of the MTL loci and susceptibility to two antifungal agents of Candida glabrata clinical isolates

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    María Teresa Lavaniegos-Sobrino

    2009-08-01

    Full Text Available The opportunistic fungal pathogen Candida glabrata is the second most common isolate from bloodstream infections worldwide and is naturally less susceptible to the antifungal drug fluconazole than other Candida species. C. glabrata is a haploid yeast that contains three mating-type like loci (MTL, although no sexual cycle has been described. Strains containing both types of mating information at the MTL1 locus are found in clinical isolates, but it is thought that strains containing type a information are more common. Here we investigated if a particular combination of mating type information at each MTLlocus is more prevalent in clinical isolates from hospitalized patients in Mexico and if there is a correlation between mating information and resistance to fluconazole and 5-fluorocytosine. We found that while both types of information at MTL1 are equally represented in a collection of 64 clinical isolates, the vast majority of isolates contain a-type information at MTL2 and α-type at MTL3. We also found no correlation of the particular combination of mating type information at the three MTL loci and resistance to fluconazole.

  1. The cacao pathogen Moniliophthora roreri (Marasmiaceae) possesses biallelic A and B mating loci but reproduces clonally.

    Science.gov (United States)

    Díaz-Valderrama, J R; Aime, M C

    2016-06-01

    The cacao pathogen Moniliophthora roreri belongs to the mushroom-forming family Marasmiaceae, but it has never been observed to produce a fruiting body, which calls to question its capacity for sexual reproduction. In this study, we identified potential A (HD1 and HD2) and B (pheromone precursors and pheromone receptors) mating genes in M. roreri. A PCR-based method was subsequently devised to determine the mating type for a set of 47 isolates from across the geographic range of the fungus. We developed and generated an 11-marker microsatellite set and conducted association and linkage disequilibrium (standardized index of association, IA(s)) analyses. We also performed an ancestral reconstruction analysis to show that the ancestor of M. roreri is predicted to be heterothallic and tetrapolar, which together with sliding window analyses support that the A and B mating loci are likely unlinked and follow a tetrapolar organization within the genome. The A locus is composed of a pair of HD1 and HD2 genes, whereas the B locus consists of a paired pheromone precursor, Mr_Ph4, and receptor, STE3_Mr4. Two A and B alleles but only two mating types were identified. Association analyses divided isolates into two well-defined genetically distinct groups that correlate with their mating type; IA(s) values show high linkage disequilibrium as is expected in clonal reproduction. Interestingly, both mating types were found in South American isolates but only one mating type was found in Central American isolates, supporting a prior hypothesis of clonal dissemination throughout Central America after a single or very few introductions of the fungus from South America.

  2. White-opaque Switching in Different Mating Type-like Locus Gene Types of Clinical Candida albicans Isolates

    Science.gov (United States)

    Li, Hou-Min; Shimizu-Imanishi, Yumi; Tanaka, Reiko; Li, Ruo-Yu; Yaguchi, Takashi

    2016-01-01

    Background: Candida albicans (C. albicans) can become a pathogen causing superficial as well as life-threatening systemic infections, especially in immunocompromised patients. Many phenotypic attributes contribute to its capacity to colonize human organs. In our study, 93 C. albicans isolates from patients of various candidiasis in a hospital of China were surveyed. We aimed to investigate the white-opaque (WO) switching competence, drug sensitivity, and virulence of mating type-like (MTL) a/α isolates. Methods: Internal transcribed spacer (ITS) gene and the MTL configuration were detected in all the isolates by reverse transcription-polymerase chain reaction. White/opaque phenotype and doubling time of cell growth were determined. The minimum inhibitory concentrations of antifungal agent were measured using broth microdilution method. Results: Sixty-four isolates (69.6%) were classified to serotype A, 19 (20.6%) to serotype B, and 9 (9.8%) to serotype C. Moreover, phylogenetic analysis showed that these isolates were divided into four different subgroups of ITS genotypes. Most of our clinical isolates were MTLa/α type, while 6.8% remained MTLa or MTLα type. The frequency of opaque phenotype was 71.0% (66 isolates). Following the guidelines of Clinical and Laboratory Standards Institute M27-A3, all isolates were susceptible to caspofungin and a few (0.6–3.2%) of them showed resistance against amphotericin B, flucytosine, fluconazole, itraconazole, and voriconazole. Conclusions: From these analyses, there were comparatively more C. albicans strains classified into serotype B, and the frequency of opaque phase strains was significant in the clinical isolates from China. Genetic, phenotypic, or drug susceptibility patterns were not significantly different from previous studies. MTLa/α isolates could also undergo WO switching which facilitates their survival. PMID:27824006

  3. A MADS box protein interacts with a mating-type protein and is required for fruiting body development in the homothallic ascomycete Sordaria macrospora.

    Science.gov (United States)

    Nolting, Nicole; Pöggeler, Stefanie

    2006-07-01

    MADS box transcription factors control diverse developmental processes in plants, metazoans, and fungi. To analyze the involvement of MADS box proteins in fruiting body development of filamentous ascomycetes, we isolated the mcm1 gene from the homothallic ascomycete Sordaria macrospora, which encodes a putative homologue of the Saccharomyces cerevisiae MADS box protein Mcm1p. Deletion of the S. macrospora mcm1 gene resulted in reduced biomass, increased hyphal branching, and reduced hyphal compartment length during vegetative growth. Furthermore, the S. macrospora Deltamcm1 strain was unable to produce fruiting bodies or ascospores during sexual development. A yeast two-hybrid analysis in conjugation with in vitro analyses demonstrated that the S. macrospora MCM1 protein can interact with the putative transcription factor SMTA-1, encoded by the S. macrospora mating-type locus. These results suggest that the S. macrospora MCM1 protein is involved in the transcriptional regulation of mating-type-specific genes as well as in fruiting body development.

  4. Diazotrophic microbial mats

    NARCIS (Netherlands)

    Severin, I.; Stal, L.J.; Seckbach, J.; Oren, A.

    2010-01-01

    Microbial mats have been the focus of scientific research for a few decades. These small-scale ecosystems are examples of versatile benthic communities of microorganisms, usually dominated by phototrophic bacteria (e.g., Krumbein et al., 1977; Jørgensen et al., 1983). They develop as vertically

  5. Isolation and characterization of the mating type locus of Mycosphaerella fijiensis, the causal agent of black leaf streak disease of banana

    NARCIS (Netherlands)

    Conde, L.; Waalwijk, C.; Canto-Canché, B.B.; Kema, G.H.J.; Crous, P.W.; James, A.C.; Abeln, E.C.A.

    2007-01-01

    Idiomorphs mat1-1 and mat1-2 from Mycosphaerella fijiensis, the causal agent of black leaf streak disease of banana, were isolated. Degenerate oligos were used to amplify the HMG box of the mat1-2 idiomorph from M. fijiensis, showing homology with the HMG box of Mycosphaerella graminicola. Using a

  6. Functional and Expression Analyses of the Pneumocystis MAT Genes Suggest Obligate Sexuality through Primary Homothallism within Host Lungs

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    S. Richard

    2018-02-01

    Full Text Available Fungi of the genus Pneumocystis are obligate parasites that colonize mammals’ lungs and are host species specific. Pneumocystis jirovecii and Pneumocystis carinii infect, respectively, humans and rats. They can turn into opportunistic pathogens in immunosuppressed hosts, causing severe pneumonia. Their cell cycle is poorly known, mainly because of the absence of an established method of culture in vitro. It is thought to include both asexual and sexual phases. Comparative genomic analysis suggested that their mode of sexual reproduction is primary homothallism involving a single mating type (MAT locus encompassing plus and minus genes (matMc, matMi, and matPi; Almeida et al., mBio 6:e02250-14, 2015. Thus, each strain would be capable of sexual reproduction alone (self-fertility. However, this is a working hypothesis derived from computational analyses that is, in addition, based on the genome sequences of single isolates. Here, we tested this hypothesis in the wet laboratory. The function of the P. jirovecii and P. carinii matMc genes was ascertained by restoration of sporulation in the corresponding mutant of fission yeast. Using PCR, we found the same single MAT locus in all P. jirovecii isolates and showed that all three MAT genes are often concomitantly expressed during pneumonia. Extensive homology searches did not identify other types of MAT transcription factors in the genomes or cis-acting motifs flanking the MAT locus that could have been involved in MAT switching or silencing. Our observations suggest that Pneumocystis sexuality through primary homothallism is obligate within host lungs to complete the cell cycle, i.e., produce asci necessary for airborne transmission to new hosts.

  7. Gene genealogies indicates abundant gene conversions and independent evolutionary histories of the mating-type chromosomes in the evolutionary history of Neurospora tetrasperma

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    Whittle Carrie A

    2010-07-01

    Full Text Available Abstract Background The self-fertile filamentous ascomycete Neurospora tetrasperma contains a large (~7 Mbp and young (mat chromosomes. The objective of the present study is to reveal the evolutionary history, including key genomic events, associated with the various regions of the mat chromosomes among ten strains representing all the nine known species (lineages contained within the N. tetrasperma species complex. Results Comparative analysis of sequence divergence among alleles of 24 mat-linked genes (mat A and mat a indicates that a large region of suppressed recombination exists within the mat chromosome for each of nine lineages of N. tetrasperma sensu latu. The recombinationally suppressed region varies in size and gene composition among lineages, and is flanked on both ends by normally recombining regions. Genealogical analyses among lineages reveals that eight gene conversion events have occurred between homologous mat A and mat a-linked alleles of genes located within the region of restricted recombination during the evolutionary history of N. tetrasperma. Conclusions We conclude that the region of suppressed recombination in the mat chromosomes has likely been subjected to independent contraction and/or expansion during the evolutionary history of the N. tetrasperma species complex. Furthermore, we infer that gene conversion events are likely a common phenomenon within this recombinationally suppressed genomic region. We argue that gene conversions might provide an efficient mechanism of adaptive editing of functional genes, including the removal of deleterious mutations, within the young recombinationally suppressed region of the mat chromosomes.

  8. Molecular ecology of microbial mats

    NARCIS (Netherlands)

    Bolhuis, H.; Cretoiu, M.S.; Stal, L.J.

    2014-01-01

    Phototrophic microbial mats are ideal model systems for ecological and evolutionary analysis of highly diverse microbial communities. Microbial mats are small-scale, nearly closed, and self-sustaining benthic ecosystems that comprise the major element cycles, trophic levels, and food webs. The steep

  9. Recurrent polymorphic mating type variation in Madagascan Bulbophyllum species (Orchidaceae) exemplifies a high incidence of auto-pollination in tropical orchids

    Science.gov (United States)

    Gamisch, Alexander; Fischer, Gunter A; Comes, Hans Peter

    2014-01-01

    The transition from outcrossing to self-fertilization is one of the most common evolutionary changes in angiosperms. The orchid family exemplifies this evolutionary trend but, because of a general lack of large-scale surveys on auto-pollination in orchid taxa, the incidence and modes of auto-pollination among (sub)tropical orchids remain poorly known. In the present study, we assessed the frequency and mode of auto-pollination within and among species of a largely monophyletic group of Madagascan Bulbophyllum. The capacity for autonomous fruit set was investigated by bagging experiments in the greenhouse and the field, complemented with detailed floral micromorphological studies of the gynostemium. Our survey comprises 393 accessions, representing at least 78 species, and thus approximately 37% of the species diversity of the genus in the Madagascan region. Our studies revealed that mating type is directly related to gynostemium structure, most often involving the presence or absence of a physical barrier termed ‘rostellum’. As a novel and unexpected finding, we identified eight species of a single lineage of Madagascan Bulbophyllum (termed ‘clade C’), in which auto-pollinating morphs (selfers), either lacking a rostellum or (rarely) possessing a stigmatic rostellum, co-exist with their pollinator-dependent conspecifics (outcrossers). We hypothesize that auto-pollination via rostellum abortion has a simple genetic basis, and probably evolved rapidly and recurrently by subtle changes in the timing of rostellum development (heterochrony). Thus, species of clade C may have an intrinsic genetic and developmental lability toward auto-pollination, allowing rapid evolutionary response under environmental, perhaps human-disturbed conditions favouring reproductive assurance. Overall, these findings should stimulate further research on the incidence, evolution, and maintenance of mating type variation in tropical orchids, as well as how they adapt(ed) to changing

  10. MICROBIAL MATS - A JOINT VENTURE

    NARCIS (Netherlands)

    VANGEMERDEN, H

    Microbial mats characteristically are dominated by a few functional groups of microbes: cyanobacteria, colorless sulfur bacteria, purple sulfur bacteria, and sulfate-reducing bacteria. Their combined metabolic activities result in steep environmental microgradients, particularly of oxygen and

  11. Allelic exchange of pheromones and their receptors reprograms sexual identity in Cryptococcus neoformans.

    OpenAIRE

    Brynne C Stanton; Steven S Giles; Mark W Staudt; Emilia K Kruzel; Christina M Hull

    2010-01-01

    Cell type specification is a fundamental process that all cells must carry out to ensure appropriate behaviors in response to environmental stimuli. In fungi, cell identity is critical for defining "sexes" known as mating types and is controlled by components of mating type (MAT) loci. MAT-encoded genes function to define sexes via two distinct paradigms: 1) by controlling transcription of components common to both sexes, or 2) by expressing specially encoded factors (pheromones and their rec...

  12. Mating type gene homologues and putative sex pheromone-sensing pathway in arbuscular mycorrhizal fungi, a presumably asexual plant root symbiont.

    Directory of Open Access Journals (Sweden)

    Sébastien Halary

    Full Text Available The fungal kingdom displays a fascinating diversity of sex-determination systems. Recent advances in genomics provide insights into the molecular mechanisms of sex, mating type determination, and evolution of sexual reproduction in many fungal species in both ancient and modern phylogenetic lineages. All major fungal groups have evolved sexual differentiation and recombination pathways. However, sexuality is unknown in arbuscular mycorrhizal fungi (AMF of the phylum Glomeromycota, an ecologically vital group of obligate plant root symbionts. AMF are commonly considered an ancient asexual lineage dating back to the Ordovician, approximately 460 M years ago. In this study, we used genomic and transcriptomic surveys of several AMF species to demonstrate the presence of conserved putative sex pheromone-sensing mitogen-activated protein (MAP kinases, comparable to those described in Ascomycota and Basidiomycota. We also find genes for high mobility group (HMG transcription factors, homologous to SexM and SexP genes in the Mucorales. The SexM genes show a remarkable sequence diversity among multiple copies in the genome, while only a single SexP sequence was detected in some isolates of Rhizophagus irregularis. In the Mucorales and Microsporidia, the sexM gene is flanked by genes for a triosephosphate transporter (TPT and a RNA helicase, but we find no evidence for synteny in the vicinity of the Sex locus in AMF. Nonetheless, our results, together with previous observations on meiotic machinery, suggest that AMF could undergo a complete sexual reproduction cycle.

  13. Genius loci / Madis Kõiv

    Index Scriptorium Estoniae

    Kõiv, Madis, 1929-2014

    2005-01-01

    Ettekanne 37. Kreutzwaldi päevadel Tartu Kirjandusmuuseumis 18.-19. dets. 1993, pealkirjaga "Kus on see Valga, kus on see Tartu...: Genius loci B. Kangro ja V. Uibopuu romaanides". Varem ilmunud: Akadeemia, 1994, nr. 4

  14. Matérn thinned Cox processes

    DEFF Research Database (Denmark)

    Andersen, Ina Trolle; Hahn, Ute

    2016-01-01

    and hard core behaviour can be achieved by applying a dependent Matérn thinning to a Cox process. An exact formula for the intensity of a Matérn thinned shot noise Cox process is derived from the Palm distribution. For the more general class of Matérn thinned Cox processes, formulae for the intensity...

  15. Matérn thinned Cox processes

    DEFF Research Database (Denmark)

    Andersen, Ina Trolle; Hahn, Ute

    of clustering and hard core behaviour can be achieved by applying a dependent Matérn thinning to a Cox process. An exact formula for the intensity of a Matérn thinned shot noise Cox process is derived from the Palm distribution. For the more general class of Matérn thinned Cox processes, formulae...

  16. Ectomycorrhizal mats alter forest soil biogeochemistry

    Science.gov (United States)

    Laurel A. Kluber; Kathryn M. Tinnesand; Bruce A. Caldwell; Susie M. Dunham; Rockie R. Yarwood; Peter J. Bottomley; David D. Myrold

    2010-01-01

    Dense hyphal mats formed by ectomycorrhizal (EcM) fungi are prominent features in Douglas-fir forest ecosystems, and have been estimated to cover up to 40% of the soil surface in some forest stands. Two morphotypes of EcM mats have been previously described: rhizomorphic mats, which have thick hyphal rhizomorphs and are found primarily in the organic horizon, and...

  17. Alternative Mating Type Configurations (a/α versus a/a or α/α) of Candida albicans Result in Alternative Biofilms Regulated by Different Pathways

    Science.gov (United States)

    Srikantha, Thyagarajan; Huang, Guanghua; Garnaas, Adam M.; Soll, David R.

    2011-01-01

    Similar multicellular structures can evolve within the same organism that may have different evolutionary histories, be controlled by different regulatory pathways, and play similar but nonidentical roles. In the human fungal pathogen Candida albicans, a quite extraordinary example of this has occurred. Depending upon the configuration of the mating type locus (a/α versus a/a or α/α), C. albicans forms alternative biofilms that appear similar morphologically, but exhibit dramatically different characteristics and are regulated by distinctly different signal transduction pathways. Biofilms formed by a/α cells are impermeable to molecules in the size range of 300 Da to 140 kDa, are poorly penetrated by human polymorphonuclear leukocytes (PMNs), and are resistant to antifungals. In contrast, a/a or α/α biofilms are permeable to molecules in this size range, are readily penetrated by PMNs, and are susceptible to antifungals. By mutational analyses, a/α biofilms are demonstrated to be regulated by the Ras1/cAMP pathway that includes Ras1→Cdc35→cAMP(Pde2—|)→Tpk2(Tpk1)→Efg1→Tec1→Bcr1, and a/a biofilms by the MAP kinase pathway that includes Mfα→Ste2→ (Ste4, Ste18, Cag1)→Ste11→Hst7→Cek2(Cek1)→Tec1. These observations suggest the hypothesis that while the upstream portion of the newly evolved pathway regulating a/a and α/α cell biofilms was derived intact from the upstream portion of the conserved pheromone-regulated pathway for mating, the downstream portion was derived through modification of the downstream portion of the conserved pathway for a/α biofilm formation. C. albicans therefore forms two alternative biofilms depending upon mating configuration. PMID:21829325

  18. Projet ViscoMatData

    OpenAIRE

    ENGUENG,; ABIB,

    2009-01-01

    ViscoMatData est un logiciel extranet d'une gestion d'une base de données multilingue sur les propriétés des matériaux viscoélastiques des chaussées. Ce rapport constitue l'un des livrables de la deuxième partie de ce projet. Pour présenter le travail réalisé durant cette deuxième partie, nous commencerons par faire un rappel sur le contexte du projet et le projet et le projet lui-même. Puis, nous nous intéresserons à l'architecture mise en place pour le développement, la réalisation et nous ...

  19. Preface - BraMat 2017

    Science.gov (United States)

    Munteanu, Daniel

    2018-04-01

    The main goal of the BraMat 2017 Conference was, as for the previous editions, to stimulate an international exchange of information in the field of materials science and engineering and to establish future research directions. The main topics of this edition included: ​Metallic materials (Section I), Biomaterials (Section II), Ceramics, polymers and composite materials (Section III), Surface engineering (Section IV), Nanomaterials (Section V), Welding engineering (Section VI), Safety engineering (Section VII), and Magnesium science and engineering (Section VIII).

  20. Safety Protocols at MAT Lab

    International Nuclear Information System (INIS)

    Wadawale, A.; Chopade, S.; Chaudhury, K.; Pal, M.K.; Kushwah, N.; Shah, A.Y.; Kedarnath, G.; Priyadarsini, K.I.; Jain, V.K.

    2017-01-01

    MAT Lab of Chemistry Division, BARC (A Class 10000 Clean room laboratory) has been in operation since 2004 for process development of ultra-purification of several strategically important materials (Ga, As, Sb, In, CsI and Ge) and synthesis of their organometallic compounds. Of these, work related to purification of As, Sb, and In, has been discontinued. Due to high toxicity and pyrophoric nature of some of the compounds, stringent safety regulations were formulated and subsequently implemented by the division

  1. Foam-mat drying technology: A review.

    Science.gov (United States)

    Hardy, Z; Jideani, V A

    2017-08-13

    This article reviews various aspects of foam-mat drying such as foam-mat drying processing technique, main additives used for foam-mat drying, foam-mat drying of liquid and solid foods, quality characteristics of foam-mat dried foods, and economic and technical benefits for employing foam-mat drying. Foam-mat drying process is an alternative method that allows the removal of water from liquid materials and pureed materials. In this drying process, a liquid material is converted into foam that is stable by being whipped after adding an edible foaming agent. The stable foam is then spread out in sheet or mat and dried by using hot air (40-90°C) at atmospheric pressure. Methyl cellulose (0.25-2%), egg white (3-20%), maltodextrin (0.5-05%), and gum Arabic (2-9%) are the commonly utilized additives for the foam-mat drying process at the given range, either combined together for their effectiveness or individual effect. The foam-mat drying process is suitable for heat sensitive, viscous, and sticky products that cannot be dried using other forms of drying methods such as spray drying because of the state of product. More interest has developed for foam-mat drying because of the simplicity, cost effectiveness, high speed drying, and improved product quality it provides.

  2. MatLab Script and Functional Programming

    Science.gov (United States)

    Shaykhian, Gholam Ali

    2007-01-01

    MatLab Script and Functional Programming: MatLab is one of the most widely used very high level programming languages for scientific and engineering computations. It is very user-friendly and needs practically no formal programming knowledge. Presented here are MatLab programming aspects and not just the MatLab commands for scientists and engineers who do not have formal programming training and also have no significant time to spare for learning programming to solve their real world problems. Specifically provided are programs for visualization. The MatLab seminar covers the functional and script programming aspect of MatLab language. Specific expectations are: a) Recognize MatLab commands, script and function. b) Create, and run a MatLab function. c) Read, recognize, and describe MatLab syntax. d) Recognize decisions, loops and matrix operators. e) Evaluate scope among multiple files, and multiple functions within a file. f) Declare, define and use scalar variables, vectors and matrices.

  3. Investigation of VEGGIE Root Mat

    Science.gov (United States)

    Subbiah, Arun M.

    2013-01-01

    VEGGIE is a plant growth facility that utilizes the phenomenon of capillary action as its primary watering system. A cloth made of Meta Aramid fiber, known as Nomex is used to wick water up from a reservoir to the bottom of the plants roots. This root mat system is intended to be low maintenance with no moving parts and requires minimal crew interface time. Unfortunately, the water wicking rates are inconsistent throughout the plant life cycle, thus causing plants to die. Over-wicking of water occurs toward the beginning of the cycle, while under-wicking occurs toward the middle. This inconsistency of wicking has become a major issue, drastically inhibiting plant growth. The primary objective is to determine the root cause of the inconsistent wicking through experimental testing. Suspect causes for the capillary water column to break include: a vacuum effect due to a negative pressure gradient in the water reservoir, contamination of material due to minerals in water and back wash from plant fertilizer, induced air bubbles while using syringe refill method, and material limitations of Nomex's ability to absorb and retain water. Experimental testing will be conducted to systematically determine the cause of under and over-wicking. Pressure gages will be used to determine pressure drop during the course of the plant life cycle and during the water refill process. A debubbler device will be connected to a root mat in order to equalize pressure inside the reservoir. Moisture and evaporation tests will simultaneously be implemented to observe moisture content and wicking rates over the course of a plant cycle. Water retention tests will be performed using strips of Nomex to determine materials wicking rates, porosity, and absorptivity. Through these experimental tests, we will have a better understanding of material properties of Nomex, as well as determine the root cause of water column breakage. With consistent test results, a forward plan can be achieved to resolve

  4. A novel type of silencing factor, Clr2, is necessary for transcriptional silencing at various chromosomal locations in the fission yeast Schizosaccharomyces pombe

    DEFF Research Database (Denmark)

    Bjerling, Pernilla; Ekwall, Karl; Egel, Richard

    2004-01-01

    The mating-type region of the fission yeast Schizosaccharomyces pombe comprises three loci: mat1, mat2-P and mat3-M. mat1 is expressed and determines the mating type of the cell. mat2-P and mat3-M are two storage cassettes located in a 17 kb heterochromatic region with features identical to those...... of mammalian heterochromatin. Mutations in the swi6+, clr1+, clr2+, clr3+, clr4+ and clr6+ genes were obtained in screens for factors necessary for silencing the mat2-P-mat3-M region. swi6+ encodes a chromodomain protein, clr3+ and clr6+ histone deacetylases, and clr4+ a histone methyltransferase. Here, we...

  5. Microbial communities and exopolysaccharides from Polynesian mats.

    Science.gov (United States)

    Rougeaux, H; Guezennec, M; Che, L M; Payri, C; Deslandes, E; Guezennec, J

    2001-03-01

    Microbial mats present in two shallow atolls of French Polynesia were characterized by high amounts of exopolysaccharides associated with cyanobacteria as the predominating species. Cyanobacteria were found in the first centimeters of the gelatinous mats, whereas deeper layers showing the occurrence of the sulfate reducers Desulfovibrio and Desulfobacter species as determined by the presence of specific biomarkers. Exopolysaccharides were extracted from these mats and partially characterized. All fractions contained both neutral sugars and uronic acids with a predominance of the former. The large diversity in monosaccharides can be interpreted as the result of exopolymer biosynthesis by either different or unidentified cyanobacterial species.

  6. BPS Jumping Loci are Automorphic

    Science.gov (United States)

    Kachru, Shamit; Tripathy, Arnav

    2018-06-01

    We show that BPS jumping loci-loci in the moduli space of string compactifications where the number of BPS states jumps in an upper semi-continuous manner—naturally appear as Fourier coefficients of (vector space-valued) automorphic forms. For the case of T 2 compactification, the jumping loci are governed by a modular form studied by Hirzebruch and Zagier, while the jumping loci in K3 compactification appear in a story developed by Oda and Kudla-Millson in arithmetic geometry. We also comment on some curious related automorphy in the physics of black hole attractors and flux vacua.

  7. Development of kenaf mat for slope stabilization

    Science.gov (United States)

    Ahmad, M. M.; Manaf, M. B. H. Ab; Zainol, N. Z.

    2017-09-01

    This study focusing on the ability of kenaf mat to act as reinforcement to laterite compared to the conventional geosynthetic in term of stabilizing the slope. Kenaf mat specimens studied in this paper are made up from natural kenaf fiber with 3mm thickness, 150mm length and 20mm width. With the same size of specimens, geosynthetic that obtain from the industry are being tested for both direct shear and tensile tests. Plasticity index of the soil sample used is equal to 13 which indicate that the soil is slightly plastic. Result shows that the friction angle of kenaf mat is higher compared to friction between soil particles itself. In term of resistance to tensile load, the tensile strength of kenaf mat is 0.033N/mm2 which is lower than the tensile strength of geosynthetic.

  8. DNA Barcoding the Canadian Arctic Flora: Core Plastid Barcodes (rbcL + matK) for 490 Vascular Plant Species

    Science.gov (United States)

    Saarela, Jeffery M.; Sokoloff, Paul C.; Gillespie, Lynn J.; Consaul, Laurie L.; Bull, Roger D.

    2013-01-01

    Accurate identification of Arctic plant species is critical for understanding potential climate-induced changes in their diversity and distributions. To facilitate rapid identification we generated DNA barcodes for the core plastid barcode loci (rbcL and matK) for 490 vascular plant species, representing nearly half of the Canadian Arctic flora and 93% of the flora of the Canadian Arctic Archipelago. Sequence recovery was higher for rbcL than matK (93% and 81%), and rbcL was easier to recover than matK from herbarium specimens (92% and 77%). Distance-based and sequence-similarity analyses of combined rbcL + matK data discriminate 97% of genera, 56% of species, and 7% of infraspecific taxa. There is a significant negative correlation between the number of species sampled per genus and the percent species resolution per genus. We characterize barcode variation in detail in the ten largest genera sampled (Carex, Draba, Festuca, Pedicularis, Poa, Potentilla, Puccinellia, Ranunculus, Salix, and Saxifraga) in the context of their phylogenetic relationships and taxonomy. Discrimination with the core barcode loci in these genera ranges from 0% in Salix to 85% in Carex. Haplotype variation in multiple genera does not correspond to species boundaries, including Taraxacum, in which the distribution of plastid haplotypes among Arctic species is consistent with plastid variation documented in non-Arctic species. Introgression of Poa glauca plastid DNA into multiple individuals of P. hartzii is problematic for identification of these species with DNA barcodes. Of three supplementary barcode loci (psbA–trnH, psbK–psbI, atpF–atpH) collected for a subset of Poa and Puccinellia species, only atpF–atpH improved discrimination in Puccinellia, compared with rbcL and matK. Variation in matK in Vaccinium uliginosum and rbcL in Saxifraga oppositifolia corresponds to variation in other loci used to characterize the phylogeographic histories of these Arctic-alpine species. PMID

  9. Library Spirit and Genius Loci

    DEFF Research Database (Denmark)

    Dahlkild, Nan

    2009-01-01

    The architecture and design of Nyborg Public Library in the light of the concepts "Library Spirit" and "Genius Loci", related to contemporary social and cultural movements, the development of the early welfare state and the "Scandinavian Style".......The architecture and design of Nyborg Public Library in the light of the concepts "Library Spirit" and "Genius Loci", related to contemporary social and cultural movements, the development of the early welfare state and the "Scandinavian Style"....

  10. Investigation of needleless electrospun PAN nanofiber mats

    Science.gov (United States)

    Sabantina, Lilia; Mirasol, José Rodríguez; Cordero, Tomás; Finsterbusch, Karin; Ehrmann, Andrea

    2018-04-01

    Polyacrylonitrile (PAN) can be spun from a nontoxic solvent (DMSO, dimethyl sulfoxide) and is nevertheless waterproof, opposite to the biopolymers which are spinnable from aqueous solutions. This makes PAN an interesting material for electrospinning nanofiber mats which can be used for diverse biotechnological or medical applications, such as filters, cell growth, wound healing or tissue engineering. On the other hand, PAN is a typical base material for producing carbon nanofibers. Nevertheless, electrospinning PAN necessitates convenient spinning parameters to create nanofibers without too many membranes or agglomerations. Thus we have studied the influence of spinning parameters on the needleless electrospinning process of PAN dissolved in DMSO and the resulting nanofiber mats.

  11. Fruiting Body Formation in Volvariella volvacea Can Occur Independently of Its MAT-A-Controlled Bipolar Mating System, Enabling Homothallic and Heterothallic Life Cycles

    Directory of Open Access Journals (Sweden)

    Bingzhi Chen

    2016-07-01

    Full Text Available Volvariella volvacea is an important crop in Southeast Asia, but erratic fruiting presents a serious challenge for its production and breeding. Efforts to explain inconsistent fruiting have been complicated by the multinucleate nature, typical lack of clamp connections, and an incompletely identified sexual reproductive system. In this study, we addressed the life cycle of V. volvacea using whole genome sequencing, cloning of MAT loci, karyotyping of spores, and fruiting assays. Microscopy analysis of spores had previously indicated the possible coexistence of heterothallic and homothallic life cycles. Our analysis of the MAT loci showed that only MAT-A, and not MAT-B, controlled heterokaryotization. Thus, the heterothallic life cycle was bipolar. Karyotyping of single spore isolates (SSIs using molecular markers supported the existence of heterokaryotic spores. However, most SSIs were clearly not heterokaryotic, yet contained structural variation (SV markers relating to both alleles of both parents. Heterokaryons from crossed, self-sterile homokaryons could produce fruiting bodies, agreeing with bipolar heterothallism. Meanwhile, some SSIs with two different MAT-A loci also produced fruiting bodies, which supported secondary homothallism. Next, SSIs that clearly contained only one MAT-A locus (homothallism were also able to fruit, demonstrating that self-fertile SSIs were not, per definition, secondary homothallic, and that a third life cycle or genetic mechanism must exist. Finally, recombination between SV markers was normal, yet 10 out of 24 SV markers showed 1:2 or 1:3 distributions in the spores, and large numbers of SSIs contained doubled SV markers. This indicated selfish genes, and possibly partial aneuploidy.

  12. HiRadMat: materials under scrutiny

    CERN Multimedia

    Anaïs Schaeffer

    2011-01-01

    CERN's new facility, HiRadMat (High Radiation to Materials), which is designed to test materials for the world's future particle accelerators, should be operational and welcoming its first experiments by the end of the year.   The HiRadMat facility, located in the TNC tunnel. The materials used in the LHC and its experiments are exposed to very high-energy particles. The LHC machine experts obviously didn't wait for the first collisions in the world's most powerful accelerator to put the materials through their paces - the equipment was validated following a series of stringent tests. And these tests will get even tougher now, with the arrival of HiRadMat. The tunnel that formerly housed the West Area Neutrino Facility (WANF) has been completely revamped to make way for CERN's latest facility, HiRadMat. Supported by the Radioprotection service, a team from the Engineering (EN) Department handled the dismantling operations from October 2009 to December 2010. "We could only work on disman...

  13. The loci recommended as universal barcodes for plants on the basis of floristic studies may not work with congeneric species as exemplified by DNA barcoding of Dendrobium species

    Directory of Open Access Journals (Sweden)

    Singh Hemant

    2012-01-01

    Full Text Available Abstract Background Based on the testing of several loci, predominantly against floristic backgrounds, individual or different combinations of loci have been suggested as possible universal DNA barcodes for plants. The present investigation was undertaken to check the applicability of the recommended locus/loci for congeneric species with Dendrobium species as an illustrative example. Results Six loci, matK, rbcL, rpoB, rpoC1, trnH-psbA spacer from the chloroplast genome and ITS, from the nuclear genome, were compared for their amplification, sequencing and species discrimination success rates among multiple accessions of 36 Dendrobium species. The trnH-psbA spacer could not be considered for analysis as good quality sequences were not obtained with its forward primer. Among the tested loci, ITS, recommended by some as a possible barcode for plants, provided 100% species identification. Another locus, matK, also recommended as a universal barcode for plants, resolved 80.56% species. ITS remained the best even when sequences of investigated loci of additional Dendrobium species available on the NCBI GenBank (93, 33, 20, 18 and 17 of ITS, matK, rbcL, rpoB and rpoC1, respectively were also considered for calculating the percent species resolution capabilities. The species discrimination of various combinations of the loci was also compared based on the 36 investigated species and additional 16 for which sequences of all the five loci were available on GenBank. Two-locus combination of matK+rbcL recommended by the Plant Working Group of Consortium for Barcoding of Life (CBOL could discriminate 86.11% of 36 species. The species discriminating ability of this barcode was reduced to 80.77% when additional sequences available on NCBI were included in the analysis. Among the recommended combinations, the barcode based on three loci - matK, rpoB and rpoC1- resolved maximum number of species. Conclusions Any recommended barcode based on the loci tested so

  14. The loci recommended as universal barcodes for plants on the basis of floristic studies may not work with congeneric species as exemplified by DNA barcoding of Dendrobium species.

    Science.gov (United States)

    Singh, Hemant Kumar; Parveen, Iffat; Raghuvanshi, Saurabh; Babbar, Shashi B

    2012-01-19

    Based on the testing of several loci, predominantly against floristic backgrounds, individual or different combinations of loci have been suggested as possible universal DNA barcodes for plants. The present investigation was undertaken to check the applicability of the recommended locus/loci for congeneric species with Dendrobium species as an illustrative example. Six loci, matK, rbcL, rpoB, rpoC1, trnH-psbA spacer from the chloroplast genome and ITS, from the nuclear genome, were compared for their amplification, sequencing and species discrimination success rates among multiple accessions of 36 Dendrobium species. The trnH-psbA spacer could not be considered for analysis as good quality sequences were not obtained with its forward primer. Among the tested loci, ITS, recommended by some as a possible barcode for plants, provided 100% species identification. Another locus, matK, also recommended as a universal barcode for plants, resolved 80.56% species. ITS remained the best even when sequences of investigated loci of additional Dendrobium species available on the NCBI GenBank (93, 33, 20, 18 and 17 of ITS, matK, rbcL, rpoB and rpoC1, respectively) were also considered for calculating the percent species resolution capabilities. The species discrimination of various combinations of the loci was also compared based on the 36 investigated species and additional 16 for which sequences of all the five loci were available on GenBank. Two-locus combination of matK+rbcL recommended by the Plant Working Group of Consortium for Barcoding of Life (CBOL) could discriminate 86.11% of 36 species. The species discriminating ability of this barcode was reduced to 80.77% when additional sequences available on NCBI were included in the analysis. Among the recommended combinations, the barcode based on three loci - matK, rpoB and rpoC1- resolved maximum number of species. Any recommended barcode based on the loci tested so far, is not likely to provide 100% species identification

  15. Evaluation of six candidate DNA barcode loci for identification of five important invasive grasses in eastern Australia.

    Directory of Open Access Journals (Sweden)

    Aisuo Wang

    Full Text Available Invasive grass weeds reduce farm productivity, threaten biodiversity, and increase weed control costs. Identification of invasive grasses from native grasses has generally relied on the morphological examination of grass floral material. DNA barcoding may provide an alternative means to identify co-occurring native and invasive grasses, particularly during early growth stages when floral characters are unavailable for analysis. However, there are no universal loci available for grass barcoding. We herein evaluated the utility of six candidate loci (atpF intron, matK, ndhK-ndhC, psbE-petL, ETS and ITS for barcode identification of several economically important invasive grass species frequently found among native grasses in eastern Australia. We evaluated these loci in 66 specimens representing five invasive grass species (Chloris gayana, Eragrostis curvula, Hyparrhenia hirta, Nassella neesiana, Nassella trichotoma and seven native grass species. Our results indicated that, while no single locus can be universally used as a DNA barcode for distinguishing the grass species examined in this study, two plastid loci (atpF and matK showed good distinguishing power to separate most of the taxa examined, and could be used as a dual locus to distinguish several of the invasive from the native species. Low PCR success rates were evidenced among two nuclear loci (ETS and ITS, and few species were amplified at these loci, however ETS was able to genetically distinguish the two important invasive Nassella species. Multiple loci analyses also suggested that ETS played a crucial role in allowing identification of the two Nassella species in the multiple loci combinations.

  16. Thermodynamics and phase transformations the selected works of Mats Hillert

    CERN Document Server

    Lilensten, Jean

    2006-01-01

    This book is a compendium of Mat Hillert's publications. Mat Hillert is a world specialist in metal alloy at the origin of a universal computing code used to calculate the diagrams of phase. This work is in English.

  17. Contributions of Ectomycorrhizal Fungal Mats to Forest Soil Carbon Cycles

    Science.gov (United States)

    Kluber, L. A.; Phillips, C. L.; Myrold, D. D.; Bond, B. J.

    2008-12-01

    Ectomycorrhizal (EM) fungi are a prominent and ubiquitous feature of forest soils, forming symbioses with most tree species, yet little is known about the magnitude of their impact on forest carbon cycles. A subset of EM fungi form dense, perennial aggregations of hyphae, which have elevated respiration rates compared with neighboring non-mat soils. These mats are a foci of EM activity and thereby a natural laboratory for examining how EM fungi impact forest soils. In order to constrain the contributions of EM fungi to forest soil respiration, we quantified the proportion of respiration derived from EM mat soils in an old-growth Douglas-fir stand in western Oregon. One dominant genus of mat-forming fungi, Piloderma, covered 56% of the soil surface area. Piloderma mats were monitored for respiration rates over 15 months and found to have on average 10% higher respiration than non-mat soil. At the stand level, this amounts to roughly 6% of soil respiration due to the presence of Piloderma mats. We calculate that these mats may constitute 27% of autotrophic respiration, based on respiration rates from trenched plots in a neighboring forest stand. Furthermore, enzyme activity and microbial community profiles in mat and non-mat soil provide evidence that specialized communities utilizing chitin contribute to this increased efflux. With 60% higher chitinase activity in mats, the breakdown of chitin is likely an important carbon flux while providing carbon and nitrogen to the microbial communities associated with mats. Quantitative PCR showed similar populations of fungi and bacteria in mat and non-mat soils; however, community analysis revealed distinct fungal and bacterial communities in the two soil types. The higher respiration associated with EM mats does not appear to be due only to a proliferation of EM fungi, but to a shift in overall community composition to organisms that efficiently utilize the unique resources available within the mat, including plant and

  18. Siwonhan-mat: The third taste of Korean foods

    Directory of Open Access Journals (Sweden)

    Soon Ah Kang

    2016-03-01

    Conclusion: Siwonhan-mat is a unique sensation found in Korean food. Understanding siwonhan-mat is a key to learning about Korean food and its food culture. Therefore, this paper serves an important role in understanding Korean food. Siwonhan-mat is often mistranslated using words to describe temperature, such as cool. This misinterpretation has resulted in confusion over the original meaning of siwonhan-mat and contributed to the incorrect usage of the word.

  19. Method for production of carbon nanofiber mat or carbon paper

    Science.gov (United States)

    Naskar, Amit K.

    2015-08-04

    Method for the preparation of a non-woven mat or paper made of carbon fibers, the method comprising carbonizing a non-woven mat or paper preform (precursor) comprised of a plurality of bonded sulfonated polyolefin fibers to produce said non-woven mat or paper made of carbon fibers. The preforms and resulting non-woven mat or paper made of carbon fiber, as well as articles and devices containing them, and methods for their use, are also described.

  20. Does siwonhan-mat represent delicious in Korean foods?

    Directory of Open Access Journals (Sweden)

    Dai Ja Jang

    2016-06-01

    Conclusion: Balancing kan is a determining factor of siwonhan-mat in Korean cuisine. Particularly, a strong association between siwonhan-mat and deliciousness was found in kuk and tang, suggesting the importance of siwonhan-mat in experiencing the best flavor in Korean food.

  1. Beaded Fiber Mats of PVA Containing Unsaturated Heteropoly Salt

    Institute of Scientific and Technical Information of China (English)

    Guo Cheng YANG; Yan PAN; Jian GONG; Chang Lu SHAO; Shang Bin WEN; Chen SHAO; Lun Yu QU

    2004-01-01

    Poly(vinyl alcohol) (PVA) fiber mats containing unsaturated heteropoly salt was prepared for the first time. IR, X-ray diffraction and SEM photographs characterized the beaded fiber mats.The viscoelasticity and the conductivity of the solution were the key factors that influence the formation of the beaded fiber mats.

  2. Developing DNA barcoding (matK) primers for marama bean ...

    African Journals Online (AJOL)

    The homology found with Tylosema fassoglensis (trnK gene) and Pisum sativum (matK gene) suggests that an identical region was amplified for Tylosema esculentum. A phylogenetic tree was constructed based on the matK sequences and the results suggest that the matK region can also be used in determining levels of ...

  3. Disruption of photoautotrophic intertidal mats by filamentous fungi

    DEFF Research Database (Denmark)

    Carreira, Cátia; Staal, Marc Jaap; Falkoski, Daniel

    2015-01-01

    Summary: Ring-like structures, 2.0-4.8cm in diameter, observed in photosynthetic microbial mats on the Wadden Sea island Schiermonnikoog (the Netherlands) showed to be the result of the fungus Emericellopsis sp. degrading the photoautotrophic top layer of the mat. The mats were predominantly comp...

  4. Fisetin up-regulates the expression of adiponectin in 3T3-L1 adipocytes via the activation of silent mating type information regulation 2 homologue 1 (SIRT1)-deacetylase and peroxisome proliferator-activated receptors (PPARs).

    Science.gov (United States)

    Jin, Taewon; Kim, Oh Yoen; Shin, Min-Jeong; Choi, Eun Young; Lee, Sung Sook; Han, Ye Sun; Chung, Ji Hyung

    2014-10-29

    Adiponectin, an adipokine, has been described as showing physiological benefits against obesity-related malfunctions and vascular dysfunction. Several natural compounds that promote the expression and secretion of adipokines in adipocytes could be useful for treating metabolic disorders. This study investigated the effect of fisetin, a dietary flavonoid, on the regulation of adiponectin in adipocytes using 3T3-L1 preadipocytes. The expression and secretion of adiponectin increased in 3T3-L1 cells upon treatment with fisetin in a dose-dependent manner. Fisetin-induced adiponectin secretion was inhibited by peroxisome proliferator-activated receptor (PPAR) antagonists. It was also revealed that fisetin increased the activities of PPARs and silent mating type information regulation 2 homologue 1 (SIRT1) in a dose-dependent manner. Furthermore, the up-regulation of adiponectin and the activation of PPARs induced by fisetin were prevented by a SIRT1 inhibitor. Fisetin also promoted deacetylation of PPAR γ coactivator 1 (PGC-1) and its interaction with PPARs. SIRT knockdown by siRNA significantly decreased both adiponectin production and PPARs-PGC-1 interaction. These results provide evidence that fisetin promotes the gene expression of adiponectin through the activation of SIRT1 and PPARs in adipocytes.

  5. Mekh-mat entrance examinations problems

    CERN Document Server

    Vardi, I

    2000-01-01

    This paper provides a complete solution set to 25 ``killer problems'' given to Jewish candidates to the Mekh--mat at Moscow State University during the 1970's and 1980's. Typically, the problems are at the mathematical olympiad level and some feature interesting theorems. However, a number of the problems are flawed, or even completely wrong. The paper therefore includes an evaluation of the problems in the style of a referee report.

  6. Chemical engineering and thermodynamics using Mat lab

    International Nuclear Information System (INIS)

    Kim Heon; Kim, Moon Gap; Lee, Hak Yeong; Yeo, Yeong Gu; Ham, Seong Won

    2002-02-01

    This book consists of twelve chapters and four appendixes about chemical engineering and thermodynamics using Mat lab, which deals with introduction, energy budget, entropy, thermodynamics process, generalization on any fluid, engineering equation of state for PVT properties, deviation of the function, phase equilibrium of pure fluid, basic of multicomponent, phase equilibrium of compound by state equation, activity model and reaction system. The appendixes is about summary of computer program, related mathematical formula and material property of pure component.

  7. A propósito de la introducción de aislamientos de Phytophthora infestans para investigación en Colombia Sorne thoughts concerning the import of the mating type A2 of Phytophthora infestans into Colombia

    Directory of Open Access Journals (Sweden)

    García Dominguez Celsa

    1997-12-01

    Full Text Available Phitophthora infestans es un patógeno heterotálico que requiere dos tipos de apareamiento, A 1 y A2, para que haya reproducción sexual. El tipo A 1 se encontraba distribuido en todas las zonas productoras de papa del mundo; pero, al final de los años 1970s el tipo A2 salió de México (su centro de origen, hacia Europa y al resto del mundo. Como en Colombia no se conocía la composición de las poblaciones de este patógeno, dos grupos de investigación de la Universidad Nacional iniciaron su estudio. El grupo de la Sede Bogotá optó por la importación del tipo A2 para realizar los trabajos de investigación. El presente comunicado es una reflexión sobre los riesgos y los cuidados que se deben tener al importar un patógeno que no está
    presente en el país.Phytophthora infestans is an heterothallic pathogen that requires the presence oftwo mating types, A1 and A2, for sexual reproduction. The A1 type had a worldwide distribution, but at the end of the 70s the A2 migrated from Mexico (the center of origin to Europe and from there to the rest of the world. Since in Colombia there was no information conceming the composition of the population of this pathogen, two research groups from the Universidad Nacional de Colombia initiated studies to determine the composition of the population of this pathogen. The group from Bogota imported the A2 type. The present work contains some thoughts on the risk involved when importing alien and exotic pathogens.

  8. Charpy V, an application in Mat lab

    International Nuclear Information System (INIS)

    Castillo M, J.A.; Torres V, M.

    2003-01-01

    The obtained results with the system Charpy V V 1 designed in Mat lab for the estimate of parameters of three mathematical models are shown. The adjustment of data is used to determine the fracture energy, the lateral expansion and the percentage of ductility of steels coming from the reactor vessels of Laguna Verde, Veracruz. The data come from test tubes type Charpy V of irradiated material and not irradiated. To verify our results they were compared with those obtained by General Electric of data coming from the Laguna Verde nuclear power plant. (Author)

  9. How compressible is recombinant battery separator mat?

    Energy Technology Data Exchange (ETDEWEB)

    Pendry, C. [Hollingsworth and Vose, Postlip Mills Winchcombe (United Kingdom)

    1999-03-01

    In the past few years, the recombinant battery separator mat (RBSM) for valve-regulated lead/acid (VRLA) batteries has become the focus of much attention. Compression, and the ability of microglass separators to maintain a level of `springiness` have helped reduce premature capacity loss. As higher compressions are reached, we need to determine what, if any, damage can be caused during the assembly process. This paper reviews the findings when RBSM materials, with different surface areas, are compressed under forces up to 500 kPa in the dry state. (orig.)

  10. Contributions of ectomycorrhizal fungal mats to forest soil respiration

    Science.gov (United States)

    C. Phillips; L.A. Kluber; J.P. Martin; B.A. Caldwell; B.J. Bond

    2012-01-01

    Distinct aggregations of fungal hyphae and rhizomorphs, or “mats”, formed by some genera of ectomycorrhizal (EcM) fungi are common features of soils in coniferous forests of the Pacific Northwest. We measured in situ respiration rates of Piloderma mats and neighboring non-mat soils in an old-growth Douglas-fir forest in western Oregon to investigate whether there was...

  11. Physical and Mechanical Properties of Jute Mat Reinforced Epoxy Composites

    Directory of Open Access Journals (Sweden)

    S.M Sadaf

    2011-11-01

    Full Text Available Cellulose jute fibre offers a number of benefits as reinforcement for synthetic polymers since it has a high specific strength and stiffness, low hardness, relatively low density and biodegradability. To reduce moisture uptake and hence to improve the mechanical properties of the composites, bleached jute mats were incorporated as reinforcing elements in the epoxy matrix. Composites at varying volume fractions and different orientations of jute mat were fabricated by hot compression machine under specific pressures and temperatures. Tensile, flexure, impact and water absorption tests of composites were conducted. Jute mat oriented at (0 ± 45–90° composites showed reduced strength compared to (0–90° fibre mat composites. Impact strength and water uptake of high volume fraction jute mat reinforced composites was higher compared to that of lower volume fraction composites. Fracture surfaces of jute mat composites were analyzed under SEM. Fracture surface of (0–90° jute mat oriented composites showed twisted fibres, while (0 ± 45–90° jute mat oriented composites had fibre pull-out without any twisting. Overall, composites containing 52% jute mat at orientations of (0–90° showed better properties compared to other fabricated composites.

  12. Evaluating the Feasibility of Five Candidate DNA Barcoding Loci for Philippine Lasianthus Jack (Lasiantheae: Rubiaceae).

    Science.gov (United States)

    Arshed, Muhammad Jefte C; Valdez, Marcos B; Alejandro, Grecebio Jonathan D

    2017-01-01

    The pantropical genus Lasianthus Jack is identified for high phenotypic plasticity making traditional taxonomic identification difficult. Having some members with important medicinal properties, a precise complimentary identification through DNA barcoding is needed for species delineation. In this study, 12 samples representing six Philippine Lasianthus species were used to determine the most efficient barcoding loci among the cpDNA markers ( mat K, rbc L, rps 16, and trn T-F) and nrDNA (ITS) based on the criteria of universality, discriminatory power, and resolution of species. The results revealed that ITS has the recommended primer universality, greatest interspecific divergences, and average resolution of species. Among the cpDNA markers, mat K and rbc L are recommended but with minimal resolution of species. While trn T-F showed moderate interspecific variations and resolution of Lasianthus species, rps 16 has the lowest interspecific divergence and resolution of species. Consequently, ITS is the potential ideal DNA barcode for Lasianthus species. ITS, mat K, and rps 16 markers have the excellent amplification and sequence qualityITS marker has the highest interspecific divergence with the maximum values, followed by mat K, rbc L, trn T-F, and rps 16, respectivelyAll markers except rps 16 yielded average resolution to Lasianthus speciesITS marker is the most ideal locus in terms of excellent universality, high interspecific discriminatory ability, and average species resolution. Abbreviations used: ITS: Internal Transcribe Spacer, mat K: maturase K, rbc L: ribulose-1,5-biphospahte-carboxylase, rps 16: ribosomal protein 16 small subunit gene.

  13. Universal Plant DNA Barcode Loci May Not Work in Complex Groups: A Case Study with Indian Berberis Species

    Science.gov (United States)

    Roy, Sribash; Tyagi, Antariksh; Shukla, Virendra; Kumar, Anil; Singh, Uma M.; Chaudhary, Lal Babu; Datt, Bhaskar; Bag, Sumit K.; Singh, Pradhyumna K.; Nair, Narayanan K.; Husain, Tariq; Tuli, Rakesh

    2010-01-01

    Background The concept of DNA barcoding for species identification has gained considerable momentum in animals because of fairly successful species identification using cytochrome oxidase I (COI). In plants, matK and rbcL have been proposed as standard barcodes. However, barcoding in complex genera is a challenging task. Methodology and Principal Findings We investigated the species discriminatory power of four reportedly most promising plant DNA barcoding loci (one from nuclear genome- ITS, and three from plastid genome- trnH-psbA, rbcL and matK) in species of Indian Berberis L. (Berberidaceae) and two other genera, Ficus L. (Moraceae) and Gossypium L. (Malvaceae). Berberis species were delineated using morphological characters. These characters resulted in a well resolved species tree. Applying both nucleotide distance and nucleotide character-based approaches, we found that none of the loci, either singly or in combinations, could discriminate the species of Berberis. ITS resolved all the tested species of Ficus and Gossypium and trnH-psbA resolved 82% of the tested species in Ficus. The highly regarded matK and rbcL could not resolve all the species. Finally, we employed amplified fragment length polymorphism test in species of Berberis to determine their relationships. Using ten primer pair combinations in AFLP, the data demonstrated incomplete species resolution. Further, AFLP analysis showed that there was a tendency of the Berberis accessions to cluster according to their geographic origin rather than species affiliation. Conclusions/Significance We reconfirm the earlier reports that the concept of universal barcode in plants may not work in a number of genera. Our results also suggest that the matK and rbcL, recommended as universal barcode loci for plants, may not work in all the genera of land plants. Morphological, geographical and molecular data analyses of Indian species of Berberis suggest probable reticulate evolution and thus barcode markers may

  14. Universal plant DNA barcode loci may not work in complex groups: a case study with Indian berberis species.

    Directory of Open Access Journals (Sweden)

    Sribash Roy

    Full Text Available BACKGROUND: The concept of DNA barcoding for species identification has gained considerable momentum in animals because of fairly successful species identification using cytochrome oxidase I (COI. In plants, matK and rbcL have been proposed as standard barcodes. However, barcoding in complex genera is a challenging task. METHODOLOGY AND PRINCIPAL FINDINGS: We investigated the species discriminatory power of four reportedly most promising plant DNA barcoding loci (one from nuclear genome--ITS, and three from plastid genome--trnH-psbA, rbcL and matK in species of Indian Berberis L. (Berberidaceae and two other genera, Ficus L. (Moraceae and Gossypium L. (Malvaceae. Berberis species were delineated using morphological characters. These characters resulted in a well resolved species tree. Applying both nucleotide distance and nucleotide character-based approaches, we found that none of the loci, either singly or in combinations, could discriminate the species of Berberis. ITS resolved all the tested species of Ficus and Gossypium and trnH-psbA resolved 82% of the tested species in Ficus. The highly regarded matK and rbcL could not resolve all the species. Finally, we employed amplified fragment length polymorphism test in species of Berberis to determine their relationships. Using ten primer pair combinations in AFLP, the data demonstrated incomplete species resolution. Further, AFLP analysis showed that there was a tendency of the Berberis accessions to cluster according to their geographic origin rather than species affiliation. CONCLUSIONS/SIGNIFICANCE: We reconfirm the earlier reports that the concept of universal barcode in plants may not work in a number of genera. Our results also suggest that the matK and rbcL, recommended as universal barcode loci for plants, may not work in all the genera of land plants. Morphological, geographical and molecular data analyses of Indian species of Berberis suggest probable reticulate evolution and thus

  15. Electrospinning and stabilization of chitosan nanofiber mats

    Science.gov (United States)

    Grimmelsmann, N.; Grothe, T.; Homburg, S. V.; Ehrmann, A.

    2017-10-01

    Chitosan is of special interest for biotechnological and medical applications due to its antibacterial, antifungal and other intrinsic physical and chemical properties. The biopolymer can, e.g., be used for biotechnological purposes, as a filter medium, in medical products, etc. In all these applications, the inner surface should be maximized to increase the contact area with the filtered medium etc. and thus the chitosan’s efficacy. Chitosan dissolves in acidic solutions, opposite to neutral water. Electrospinning is possible, e.g., by co-spinning with PEO (poly(ethylene oxide)). Tests with different chitosan:PEO ratios revealed that higher PEO fractions resulted in better spinnability and more regular fibre mats, but make stabilization of the fibre structure more challenging.

  16. Flygande mat - kabinpersonals måltidssituation

    OpenAIRE

    Johansson, Johanna; Hugosson, Ellen

    2015-01-01

    Inledning Yrket som kabinanställd inom flyget präglas av serviceanda och ansvar för passagerares säkerhet. Arbetsmiljön innebär fysiska påfrestningar vad gäller till exempel kabintryck och låg syrenivå. Mat och måltider intas under olika tider på dygnet och infaller sällan på normala måltidstider. Kabinpersonalens måltider regleras av regler, avtal och policyer rörande arbetstidens längd. Syfte Syftet var att undersöka kabinpersonalens måltider under arbetstid, med fokus på riktlinjer och pol...

  17. MAT@USC Candidates and Latino English Language Learners

    Science.gov (United States)

    Lomeli, Cynthia Leticia

    2012-01-01

    The purpose of this study was to further understand the perceptions of MAT@USC teacher candidates and how their perceptions and previous experiences affect the educational experiences of Latino English language learners. Three questions were developed to guide this study: (1) What are the perceptions of MAT@USC candidates in selected courses…

  18. Matting Of Hair Due To ′Sunsilk′ Shampoo

    Directory of Open Access Journals (Sweden)

    Nadeem Mohd

    1995-01-01

    Full Text Available Matting of hair been reported from time to time due to treatment of hair with detergent, shampoos, waving lotions, setting lotions and bleaches. A case of matting of hairs in a young girl due to a change in the brand of shampoo is reported.

  19. Effects of preprocessing method on TVOC emission of car mat

    Science.gov (United States)

    Wang, Min; Jia, Li

    2013-02-01

    The effects of the mat preprocessing method on total volatile organic compounds (TVOC) emission of car mat are studied in this paper. An appropriate TVOC emission period for car mat is suggested. The emission factors for total volatile organic compounds from three kinds of new car mats are discussed. The car mats are preprocessed by washing, baking and ventilation. When car mats are preprocessed by washing, the TVOC emission for all samples tested are lower than that preprocessed in other methods. The TVOC emission is in stable situation for a minimum of 4 days. The TVOC emitted from some samples may exceed 2500μg/kg. But the TVOC emitted from washed Polyamide (PA) and wool mat is less than 2500μg/kg. The emission factors of total volatile organic compounds (TVOC) are experimentally investigated in the case of different preprocessing methods. The air temperature in environment chamber and the water temperature for washing are important factors influencing on emission of car mats.

  20. Allelic exchange of pheromones and their receptors reprograms sexual identity in Cryptococcus neoformans.

    Directory of Open Access Journals (Sweden)

    Brynne C Stanton

    2010-02-01

    Full Text Available Cell type specification is a fundamental process that all cells must carry out to ensure appropriate behaviors in response to environmental stimuli. In fungi, cell identity is critical for defining "sexes" known as mating types and is controlled by components of mating type (MAT loci. MAT-encoded genes function to define sexes via two distinct paradigms: 1 by controlling transcription of components common to both sexes, or 2 by expressing specially encoded factors (pheromones and their receptors that differ between mating types. The human fungal pathogen Cryptococcus neoformans has two mating types (a and alpha that are specified by an extremely unusual MAT locus. The complex architecture of this locus makes it impossible to predict which paradigm governs mating type. To identify the mechanism by which the C. neoformans sexes are determined, we created strains in which the pheromone and pheromone receptor from one mating type (a replaced the pheromone and pheromone receptor of the other (alpha. We discovered that these "alpha(a" cells effectively adopt a new mating type (that of a cells; they sense and respond to alpha factor, they elicit a mating response from alpha cells, and they fuse with alpha cells. In addition, alpha(a cells lose the alpha cell type-specific response to pheromone and do not form germ tubes, instead remaining spherical like a cells. Finally, we discovered that exogenous expression of the diploid/dikaryon-specific transcription factor Sxi2a could then promote complete sexual development in crosses between alpha and alpha(a strains. These data reveal that cell identity in C. neoformans is controlled fully by three kinds of MAT-encoded proteins: pheromones, pheromone receptors, and homeodomain proteins. Our findings establish the mechanisms for maintenance of distinct cell types and subsequent developmental behaviors in this unusual human fungal pathogen.

  1. Allelic exchange of pheromones and their receptors reprograms sexual identity in Cryptococcus neoformans.

    Science.gov (United States)

    Stanton, Brynne C; Giles, Steven S; Staudt, Mark W; Kruzel, Emilia K; Hull, Christina M

    2010-02-26

    Cell type specification is a fundamental process that all cells must carry out to ensure appropriate behaviors in response to environmental stimuli. In fungi, cell identity is critical for defining "sexes" known as mating types and is controlled by components of mating type (MAT) loci. MAT-encoded genes function to define sexes via two distinct paradigms: 1) by controlling transcription of components common to both sexes, or 2) by expressing specially encoded factors (pheromones and their receptors) that differ between mating types. The human fungal pathogen Cryptococcus neoformans has two mating types (a and alpha) that are specified by an extremely unusual MAT locus. The complex architecture of this locus makes it impossible to predict which paradigm governs mating type. To identify the mechanism by which the C. neoformans sexes are determined, we created strains in which the pheromone and pheromone receptor from one mating type (a) replaced the pheromone and pheromone receptor of the other (alpha). We discovered that these "alpha(a)" cells effectively adopt a new mating type (that of a cells); they sense and respond to alpha factor, they elicit a mating response from alpha cells, and they fuse with alpha cells. In addition, alpha(a) cells lose the alpha cell type-specific response to pheromone and do not form germ tubes, instead remaining spherical like a cells. Finally, we discovered that exogenous expression of the diploid/dikaryon-specific transcription factor Sxi2a could then promote complete sexual development in crosses between alpha and alpha(a) strains. These data reveal that cell identity in C. neoformans is controlled fully by three kinds of MAT-encoded proteins: pheromones, pheromone receptors, and homeodomain proteins. Our findings establish the mechanisms for maintenance of distinct cell types and subsequent developmental behaviors in this unusual human fungal pathogen.

  2. Microbial mat ecosystems: Structure types, functional diversity, and biotechnological application

    Directory of Open Access Journals (Sweden)

    Cristina M. Prieto-Barajas

    2018-01-01

    Full Text Available Microbial mats are horizontally stratified microbial communities, exhibiting a structure defined by physiochemical gradients, which models microbial diversity, physiological activities, and their dynamics as a whole system. These ecosystems are commonly associated with aquatic habitats, including hot springs, hypersaline ponds, and intertidal coastal zones and oligotrophic environments, all of them harbour phototrophic mats and other environments such as acidic hot springs or acid mine drainage harbour non-photosynthetic mats. This review analyses the complex structure, diversity, and interactions between the microorganisms that form the framework of different types of microbial mats located around the globe. Furthermore, the many tools that allow studying microbial mats in depth and their potential biotechnological applications are discussed.

  3. Potential DNA barcodes for Melilotus species based on five single loci and their combinations.

    Directory of Open Access Journals (Sweden)

    Fan Wu

    Full Text Available Melilotus, an annual or biennial herb, belongs to the tribe Trifolieae (Leguminosae and consists of 19 species. As an important green manure crop, diverse Melilotus species have different values as feed and medicine. To identify different Melilotus species, we examined the efficiency of five candidate regions as barcodes, including the internal transcribed spacer (ITS and two chloroplast loci, rbcL and matK, and two non-coding loci, trnH-psbA and trnL-F. In total, 198 individuals from 98 accessions representing 18 Melilotus species were sequenced for these five potential barcodes. Based on inter-specific divergence, we analysed sequences and confirmed that each candidate barcode was able to identify some of the 18 species. The resolution of a single barcode and its combinations ranged from 33.33% to 88.89%. Analysis of pairwise distances showed that matK+rbcL+trnL-F+trnH-psbA+ITS (MRTPI had the greatest value and rbcL the least. Barcode gap values and similarity value analyses confirmed these trends. The results indicated that an ITS region, successfully identifying 13 of 18 species, was the most appropriate single barcode and that the combination of all five potential barcodes identified 16 of the 18 species. We conclude that MRTPI is the most effective tool for Melilotus species identification. Taking full advantage of the barcode system, a clear taxonomic relationship can be applied to identify Melilotus species and enhance their practical production.

  4. Spatial patterns of cyanobacterial mat growth on sand ripples

    Science.gov (United States)

    Mariotti, G.; Klepac-Ceraj, V.; Perron, J. T.; Bosak, T.

    2016-02-01

    Photosynthetic microbial mats produce organic matter, cycle nutrients, bind pollutants and stabilize sediment in sandy marine environments. Here, we investigate the influence of bedforms and wave motion on the growth rate, composition and spatial variability of microbial mats by growing cyanobacterial mats on a rippled bed of carbonate sand in a wave tank. The tank was forced with an oscillatory flow with velocities below the threshold for sediment motion yet able to induce a porewater flow within the sediment. Different spatial patterns developed in mats depending on the initial biochemistry of the water medium. When growing in a medium rich in nitrogen, phosphorous and micronutrients, mats grew faster on ripple troughs than on ripple crests. After two months, mats covered the bed surface uniformly, and the microbial communities on the crests and in the troughs had similar compositions. Differences in bed shear stress and nutrient availability between crests and troughs were not able to explain the faster growth in the troughs. We hypothesize that this growth pattern is due to a "strainer" effect, i.e. the suspended bacteria from the inoculum were preferentially delivered to troughs by the wave-induced porewater flow. In the experiments initiated in a medium previously used up by a microbial mat and thus depleted in nutrients, mats grew preferentially on the ripple crests. This spatial pattern persisted for nearly two years, and the microbial composition on troughs and crests was different. We attribute this pattern to the upwelling of porewater in the crests, which increased the delivery of nutrients from sediment to the cyanobacteria on the bed surface. Thus, the macroscopic patterns formed by photosynthetic microbial mats on sand ripples may be used to infer whether mats are nutrient-limited and whether they are recently colonized or older than a month.

  5. Diversity and stratification of archaea in a hypersaline microbial mat.

    Science.gov (United States)

    Robertson, Charles E; Spear, John R; Harris, J Kirk; Pace, Norman R

    2009-04-01

    The Guerrero Negro (GN) hypersaline microbial mats have become one focus for biogeochemical studies of stratified ecosystems. The GN mats are found beneath several of a series of ponds of increasing salinity that make up a solar saltern fed from Pacific Ocean water pumped from the Laguna Ojo de Liebre near GN, Baja California Sur, Mexico. Molecular surveys of the laminated photosynthetic microbial mat below the fourth pond in the series identified an enormous diversity of bacteria in the mat, but archaea have received little attention. To determine the bulk contribution of archaeal phylotypes to the pond 4 study site, we determined the phylogenetic distribution of archaeal rRNA gene sequences in PCR libraries based on nominally universal primers. The ratios of bacterial/archaeal/eukaryotic rRNA genes, 90%/9%/1%, suggest that the archaeal contribution to the metabolic activities of the mat may be significant. To explore the distribution of archaea in the mat, sequences derived using archaeon-specific PCR primers were surveyed in 10 strata of the 6-cm-thick mat. The diversity of archaea overall was substantial albeit less than the diversity observed previously for bacteria. Archaeal diversity, mainly euryarchaeotes, was highest in the uppermost 2 to 3 mm of the mat and decreased rapidly with depth, where crenarchaeotes dominated. Only 3% of the sequences were specifically related to known organisms including methanogens. While some mat archaeal clades corresponded with known chemical gradients, others did not, which is likely explained by heretofore-unrecognized gradients. Some clades did not segregate by depth in the mat, indicating broad metabolic repertoires, undersampling, or both.

  6. Water flow and solute transport in floating fen root mats

    Science.gov (United States)

    Stofberg, Sija F.; EATM van der Zee, Sjoerd

    2015-04-01

    Floating fens are valuable wetlands, found in North-Western Europe, that are formed by floating root mats when old turf ponds are colonized by plants. These terrestrialization ecosystems are known for their biodiversity and the presence of rare plant species, and the root mats reveal different vegetation zones at a small scale. The vegetation zones are a result of strong gradients in abiotic conditions, including groundwater dynamics, nutrients and pH. To prevent irreversible drought effects such as land subsidence and mineralization of peat, water management involves import of water from elsewhere to maintain constant surface water levels. Imported water may have elevated levels of salinity during dry summers, and salt exposure may threaten the vegetation. To assess the risk of exposure of the rare plant species to salinity, the hydrology of such root mats must be understood. Physical properties of root mats have scarcely been investigated. We have measured soil characteristics, hydraulic conductivity, vertical root mat movement and groundwater dynamics in a floating root mat in the nature reserve Nieuwkoopse Plassen, in the Netherlands. The root mat mostly consists of roots and organic material, in which the soil has a high saturated water content, and strongly varies in its stage of decomposition. We have found a distinct negative correlation between degree of decomposition and hydraulic conductivity, similar to observations for bogs in the literature. Our results show that the relatively young, thin edge of the root mat that colonizes the surface water has a high hydraulic conductivity and floats in the surface water, resulting in very small groundwater fluctuations within the root mat. The older part of the root mat, that is connected to the deeper peat layers is hydrologically more isolated and the material has a lower conductivity. Here, the groundwater fluctuates strongly with atmospheric forcing. The zones of hydraulic properties and vegetation, appear to

  7. The internal transcribed spacer (ITS region and trnH-psbA [corrected] are suitable candidate loci for DNA barcoding of tropical tree species of India.

    Directory of Open Access Journals (Sweden)

    Abhinandan Mani Tripathi

    Full Text Available DNA barcoding as a tool for species identification has been successful in animals and other organisms, including certain groups of plants. The exploration of this new tool for species identification, particularly in tree species, is very scanty from biodiversity-rich countries like India. rbcL and matK are standard barcode loci while ITS, and trnH-psbA are considered as supplementary loci for plants.Plant barcode loci, namely, rbcL, matK, ITS, trnH-psbA, and the recently proposed ITS2, were tested for their efficacy as barcode loci using 300 accessions of tropical tree species. We tested these loci for PCR, sequencing success, and species discrimination ability using three methods. rbcL was the best locus as far as PCR and sequencing success rate were concerned, but not for the species discrimination ability of tropical tree species. ITS and trnH-psbA were the second best loci in PCR and sequencing success, respectively. The species discrimination ability of ITS ranged from 24.4 percent to 74.3 percent and that of trnH-psbA was 25.6 percent to 67.7 percent, depending upon the data set and the method used. matK provided the least PCR success, followed by ITS2 (59. 0%. Species resolution by ITS2 and rbcL ranged from 9.0 percent to 48.7 percent and 13.2 percent to 43.6 percent, respectively. Further, we observed that the NCBI nucleotide database is poorly represented by the sequences of barcode loci studied here for tree species.Although a conservative approach of a success rate of 60-70 percent by both ITS and trnH-psbA may not be considered as highly successful but would certainly help in large-scale biodiversity inventorization, particularly for tropical tree species, considering the standard success rate of plant DNA barcode program reported so far. The recommended matK and rbcL primers combination may not work in tropical tree species as barcode markers.

  8. The SNF2-family member Fun30 promotes gene silencing in heterochromatic loci.

    Directory of Open Access Journals (Sweden)

    Ana Neves-Costa

    2009-12-01

    Full Text Available Chromatin regulates many key processes in the nucleus by controlling access to the underlying DNA. SNF2-like factors are ATP-driven enzymes that play key roles in the dynamics of chromatin by remodelling nucleosomes and other nucleoprotein complexes. Even simple eukaryotes such as yeast contain members of several subfamilies of SNF2-like factors. The FUN30/ETL1 subfamily of SNF2 remodellers is conserved from yeasts to humans, but is poorly characterized. We show that the deletion of FUN30 leads to sensitivity to the topoisomerase I poison camptothecin and to severe cell cycle progression defects when the Orc5 subunit is mutated. We demonstrate a role of FUN30 in promoting silencing in the heterochromatin-like mating type locus HMR, telomeres and the rDNA repeats. Chromatin immunoprecipitation experiments demonstrate that Fun30 binds at the boundary element of the silent HMR and within the silent HMR. Mapping of nucleosomes in vivo using micrococcal nuclease demonstrates that deletion of FUN30 leads to changes of the chromatin structure at the boundary element. A point mutation in the ATP-binding site abrogates the silencing function of Fun30 as well as its toxicity upon overexpression, indicating that the ATPase activity is essential for these roles of Fun30. We identify by amino acid sequence analysis a putative CUE motif as a feature of FUN30/ETL1 factors and show that this motif assists Fun30 activity. Our work suggests that Fun30 is directly involved in silencing by regulating the chromatin structure within or around silent loci.

  9. Vulnerability of R-MAT networks with communities

    Directory of Open Access Journals (Sweden)

    Nikolay Alexandrovich Kinash

    2016-06-01

    Full Text Available A generator R-MAT for modeling networks with different laws of link constructions within and between communities has been developed. Network attack simulations have been performed and pertinent robustness of diverse network combinations has been concluded.

  10. Fabrication of nanofiber mats from electrospinning of functionalized polymers

    Science.gov (United States)

    Oktay, Burcu; Kayaman-Apohan, Nilhan; Erdem-Kuruca, Serap

    2014-08-01

    Electrospinning technique enabled us to prepare nanofibers from synthetic and natural polymers. In this study, it was aimed to fabricate electrospun poly(vinyl alcohol) (PVA) based nanofibers by reactive electrospinning process. To improve endurance of fiber toward to many solvents, PVA was functionalized with photo-crosslinkable groups before spinning. Afterward PVA was crosslinked by UV radiation during electrospinning process. The nanofiber mats were characterized by scanning electron microscopy (SEM). The results showed that homogenous, uniform and crosslinked PVA nanofibers in diameters of about 200 nm were obtained. Thermal stability of the nanofiber mat was investigated with thermal gravimetric analysis (TGA). Also the potential use of this nanofiber mats for tissue engineering was examined. Osteosarcoma (Saos) cells were cultured on the nanofiber mats.

  11. Fabrication of nanofiber mats from electrospinning of functionalized polymers

    International Nuclear Information System (INIS)

    Oktay, Burcu; Kayaman-Apohan, Nilhan; Erdem-Kuruca, Serap

    2014-01-01

    Electrospinning technique enabled us to prepare nanofibers from synthetic and natural polymers. In this study, it was aimed to fabricate electrospun poly(vinyl alcohol) (PVA) based nanofibers by reactive electrospinning process. To improve endurance of fiber toward to many solvents, PVA was functionalized with photo-crosslinkable groups before spinning. Afterward PVA was crosslinked by UV radiation during electrospinning process. The nanofiber mats were characterized by scanning electron microscopy (SEM). The results showed that homogenous, uniform and crosslinked PVA nanofibers in diameters of about 200 nm were obtained. Thermal stability of the nanofiber mat was investigated with thermal gravimetric analysis (TGA). Also the potential use of this nanofiber mats for tissue engineering was examined. Osteosarcoma (Saos) cells were cultured on the nanofiber mats

  12. Thermal Protection System Materials (TPSM): 3D MAT

    Data.gov (United States)

    National Aeronautics and Space Administration — The 3D MAT Project seeks to design and develop a game changing Woven Thermal Protection System (TPS) technology tailored to meet the needs of the Orion Multi-Purpose...

  13. Counting viruses and bacteria in photosynthetic microbial mats

    NARCIS (Netherlands)

    Carreira, C; Staal, M.; Middelboe, M.; Brussaard, C.P.D.

    2015-01-01

    Viral abundances in benthic environments are the highest found in aquatic systems. Photosynthetic microbial mats represent benthic environments with high microbial activity and possibly high viral densities, yet viral abundances have not been examined in such systems. Existing extraction procedures

  14. Biodiversity of the microbial mat of the Garga hot spring.

    Science.gov (United States)

    Rozanov, Alexey Sergeevich; Bryanskaya, Alla Victorovna; Ivanisenko, Timofey Vladimirovich; Malup, Tatyana Konstantinovna; Peltek, Sergey Evgenievich

    2017-12-28

    Microbial mats are a good model system for ecological and evolutionary analysis of microbial communities. There are more than 20 alkaline hot springs on the banks of the Barguzin river inflows. Water temperature reaches 75 °C and pH is usually 8.0-9.0. The formation of microbial mats is observed in all hot springs. Microbial communities of hot springs of the Baikal rift zone are poorly studied. Garga is the biggest hot spring in this area. In this study, we investigated bacterial and archaeal diversity of the Garga hot spring (Baikal rift zone, Russia) using 16S rRNA metagenomic sequencing. We studied two types of microbial communities: (i) small white biofilms on rocks in the points with the highest temperature (75 °C) and (ii) continuous thick phototrophic microbial mats observed at temperatures below 70 °C. Archaea (mainly Crenarchaeota; 19.8% of the total sequences) were detected only in the small biofilms. The high abundance of Archaea in the sample from hot springs of the Baikal rift zone supplemented our knowledge of the distribution of Archaea. Most archaeal sequences had low similarity to known Archaea. In the microbial mats, primary products were formed by cyanobacteria of the genus Leptolyngbya. Heterotrophic microorganisms were mostly represented by Actinobacteria and Proteobacteria in all studied samples of the microbial mats. Planctomycetes, Chloroflexi, and Chlorobi were abundant in the middle layer of the microbial mats, while heterotrophic microorganisms represented mostly by Firmicutes (Clostridia, strict anaerobes) dominated in the bottom part. Besides prokaryotes, we detect some species of Algae with help of detection their chloroplasts 16 s rRNA. High abundance of Archaea in samples from hot springs of the Baikal rift zone supplemented our knowledge of the distribution of Archaea. Most archaeal sequences had low similarity to known Archaea. Metagenomic analysis of microbial communities of the microbial mat of Garga hot spring showed that

  15. Carbon cycling and calcification in hypersaline microbial mats

    OpenAIRE

    Ludwig, Rebecca

    2004-01-01

    Phototrophic microbial mats are laminated aggregations of microorganisms that thrive in extreme and oligotrophic environments. Primary production rates by oxygenic phototrophs are extremely high. Primary producers supply heterotrophic mat members with organic carbon, which in turn regenerate CO2 needed for autotrophic carbon fixation. Another potential source of CO2 is calcification, which is known to shift the carbonate equilibrium towards CO2. This thesis investigated the carbon cycle of mi...

  16. Le matérialisme scientifique

    Science.gov (United States)

    Meunier, Jean-François

    2004-03-01

    De nos jours, il arrive quotidiennement aux grands hommes d'avoir à fréquenter d'ignorants mortels épris d'une conviction maladive que la science est la grande responsable de tous les maux du monde. Évidemment sans physique atomique, il n'y aurait pas eu d'Hiroshima et sans révolution industrielle, pas de pollution et etc. Cependant, ces accusations envers le progrès technique sont tout à fait injustes, irréfléchies et, j'irai même jusqu'à dire, irresponsables, puisque le calcul, i.e. la planification, même la plus élémentaire, est ce qui caractérise le mieux, pragmatiquement, la société humaine. À mon avis, les problèmes sociaux tireraient plutôt leur origine de sciences sociales irréalistes, qui, concrètment, inspireraient ou serviraient d'alibis à ceux qui détiennent véritablement le pouvoir. Dans cet article, je tenterai donc de démontrer la meilleure véracité et efficacité du matérialisme scientifique. Cette doctrine, dont Mario Bunge est le plus illustre représentant, s'appuy sur les résultats théoriques et expérimentaux des sciences factuelles ainsi que sur l'exactitude logique des mathématiques, utilisées ici comme langage universel de l'expression des idées. Cette conception philosophique qui s'inspire principalement du modèle des théories physiques, stipule que les réalités sociales sont, comme tout autre réalité, matérielles, mathématisables et représentables comme des systèmes en interaction. En fait, le modèle des physiciens ayant historiquement fait ses preuves en matière de testabilité et de cohérence interne est proposé d'être appliquer aux sciences sociales, aujourd'hui scindées des sciences dites pures sous l'inspiration des pseudo penseurs néo-kantiens, phénoménologiques et post-moderne. Cette nouvelle approche permettrait ainsi d'évoluer plus exactement vers une compréhension des bases sociales et biologiques du comportement humain afin de développer une éthique sans cesse plus r

  17. Regulation of electron transfer processes affects phototrophic mat structure and activity

    Science.gov (United States)

    Ha, Phuc T.; Renslow, Ryan S.; Atci, Erhan; Reardon, Patrick N.; Lindemann, Stephen R.; Fredrickson, James K.; Call, Douglas R.; Beyenal, Haluk

    2015-01-01

    Phototrophic microbial mats are among the most diverse ecosystems in nature. These systems undergo daily cycles in redox potential caused by variations in light energy input and metabolic interactions among the microbial species. In this work, solid electrodes with controlled potentials were placed under mats to study the electron transfer processes between the electrode and the microbial mat. The phototrophic microbial mat was harvested from Hot Lake, a hypersaline, epsomitic lake located near Oroville (Washington, USA). We operated two reactors: graphite electrodes were polarized at potentials of -700 mVAg/AgCl [cathodic (CAT) mat system] and +300 mVAg/AgCl [anodic (AN) mat system] and the electron transfer rates between the electrode and mat were monitored. We observed a diel cycle of electron transfer rates for both AN and CAT mat systems. Interestingly, the CAT mats generated the highest reducing current at the same time points that the AN mats showed the highest oxidizing current. To characterize the physicochemical factors influencing electron transfer processes, we measured depth profiles of dissolved oxygen (DO) and sulfide in the mats using microelectrodes. We further demonstrated that the mat-to-electrode and electrode-to-mat electron transfer rates were light- and temperature-dependent. Using nuclear magnetic resonance (NMR) imaging, we determined that the electrode potential regulated the diffusivity and porosity of the microbial mats. Both porosity and diffusivity were higher in the CAT mats than in the AN mats. We also used NMR spectroscopy for high-resolution quantitative metabolite analysis and found that the CAT mats had significantly higher concentrations of osmoprotectants such as betaine and trehalose. Subsequently, we performed amplicon sequencing across the V4 region of the 16S rRNA gene of incubated mats to understand the impact of electrode potential on microbial community structure. These data suggested that variation in the

  18. Regulation of electron transfer processes affects phototrophic mat structure and activity

    Directory of Open Access Journals (Sweden)

    Haluk eBeyenal

    2015-09-01

    Full Text Available Phototrophic microbial mats are among the most diverse ecosystems in nature. These systems undergo daily cycles in redox potential caused by variations in light energy input and metabolic interactions among the microbial species. In this work, solid electrodes with controlled potentials were placed under mats to study the electron transfer processes between the electrode and the microbial mat. The phototrophic microbial mat was harvested from Hot Lake, a hypersaline, epsomitic lake located near Oroville (Washington, USA. We operated two reactors: graphite electrodes were polarized at potentials of -700 mVAg/AgCl (cathodic mat system and +300 mVAg/AgCl (anodic mat system and the electron transfer rates between the electrode and mat were monitored. We observed a diel cycle of electron transfer rates for both anodic and cathodic mat systems. Interestingly, the cathodic mats generated the highest reducing current at the same time points that the anodic mats showed the highest oxidizing current. To characterize the physicochemical factors influencing electron transfer processes, we measured depth profiles of dissolved oxygen and sulfide in the mats using microelectrodes. We further demonstrated that the mat-to-electrode and electrode-to-mat electron transfer rates were light- and temperature-dependent. Using nuclear magnetic resonance (NMR imaging, we determined that the electrode potential regulated the diffusivity and porosity of the microbial mats. Both porosity and diffusivity were higher in the cathodic mats than in the anodic mats. We also used NMR spectroscopy for high-resolution quantitative metabolite analysis and found that the cathodic mats had significantly higher concentrations of osmoprotectants such as betaine and trehalose. Subsequently, we performed amplicon sequencing across the V4 region of the 16S rRNA gene of incubated mats to understand the impact of electrode potential on microbial community structure. These data suggested that

  19. Regulation of electron transfer processes affects phototrophic mat structure and activity.

    Science.gov (United States)

    Ha, Phuc T; Renslow, Ryan S; Atci, Erhan; Reardon, Patrick N; Lindemann, Stephen R; Fredrickson, James K; Call, Douglas R; Beyenal, Haluk

    2015-01-01

    Phototrophic microbial mats are among the most diverse ecosystems in nature. These systems undergo daily cycles in redox potential caused by variations in light energy input and metabolic interactions among the microbial species. In this work, solid electrodes with controlled potentials were placed under mats to study the electron transfer processes between the electrode and the microbial mat. The phototrophic microbial mat was harvested from Hot Lake, a hypersaline, epsomitic lake located near Oroville (Washington, USA). We operated two reactors: graphite electrodes were polarized at potentials of -700 mVAg/AgCl [cathodic (CAT) mat system] and +300 mVAg/AgCl [anodic (AN) mat system] and the electron transfer rates between the electrode and mat were monitored. We observed a diel cycle of electron transfer rates for both AN and CAT mat systems. Interestingly, the CAT mats generated the highest reducing current at the same time points that the AN mats showed the highest oxidizing current. To characterize the physicochemical factors influencing electron transfer processes, we measured depth profiles of dissolved oxygen (DO) and sulfide in the mats using microelectrodes. We further demonstrated that the mat-to-electrode and electrode-to-mat electron transfer rates were light- and temperature-dependent. Using nuclear magnetic resonance (NMR) imaging, we determined that the electrode potential regulated the diffusivity and porosity of the microbial mats. Both porosity and diffusivity were higher in the CAT mats than in the AN mats. We also used NMR spectroscopy for high-resolution quantitative metabolite analysis and found that the CAT mats had significantly higher concentrations of osmoprotectants such as betaine and trehalose. Subsequently, we performed amplicon sequencing across the V4 region of the 16S rRNA gene of incubated mats to understand the impact of electrode potential on microbial community structure. These data suggested that variation in the

  20. Quantitative Trait Loci in Inbred Lines

    NARCIS (Netherlands)

    Jansen, R.C.

    2001-01-01

    Quantitative traits result from the influence of multiple genes (quantitative trait loci) and environmental factors. Detecting and mapping the individual genes underlying such 'complex' traits is a difficult task. Fortunately, populations obtained from crosses between inbred lines are relatively

  1. Biology and applications of human minisatellite loci.

    Science.gov (United States)

    Armour, J A; Jeffreys, A J

    1992-12-01

    Highly repetitive minisatellites' include the most variable human loci described to date. They have proved invaluable in a wide variety of genetic analyses, and despite some controversies surrounding their practical implementation, have been extensively adopted in civil and forensic casework. Molecular analysis of internal allelic structure has provided detailed insights into the repeat-unit turnover mechanisms operating in germline mutations, which are ultimately responsible for the extreme variability seen at these loci.

  2. Photosynthetic Microbial Mats are Exemplary Sources of Diverse Biosignatures (Invited)

    Science.gov (United States)

    Des Marais, D. J.; Jahnke, L. L.

    2013-12-01

    Marine cyanobacterial microbial mats are widespread, compact, self-contained ecosystems that create diverse biosignatures and have an ancient fossil record. Within the mats, oxygenic photosynthesis provides organic substrates and O2 to the community. Both the absorption and scattering of light change the intensity and spectral composition of incident radiation as it penetrates a mat. Some phototrophs utilize infrared light near the base of the photic zone. A mat's upper layers can become highly reduced and sulfidic at night. Counteracting gradients of O2 and sulfide shape the chemical environment and provide daily-contrasting microenvironments separated on a scale of a few mm. Radiation hazards (UV, etc.), O2 and sulfide toxicity elicit motility and other physiological responses. This combination of benefits and hazards of light, O2 and sulfide promotes the allocation of various essential mat processes between light and dark periods and to various depths in the mat. Associated nonphotosynthetic communities, including anaerobes, strongly influence many of the ecosystem's overall characteristics, and their processes affect any biosignatures that enter the fossil record. A biosignature is an object, substance and/or pattern whose origin specifically requires a biological agent. The value of a biosignature depends not only on the probability of life creating it, but also on the improbability of nonbiological processes producing it. Microbial mats create biosignatures that identify particular groups of organisms and also reveal attributes of the mat ecosystem. For example, branched hydrocarbons and pigments can be diagnostic of cyanobacteria and other phototrophic bacteria, and isoprenoids can indicate particular groups of archea. Assemblages of lipid biosignatures change with depth due to changes in microbial populations and diagenetic transformations of organic matter. The 13C/12C values of organic matter and carbonates reflect isotopic discrimination by particular

  3. Three new loci for determining x chromosome inactivation patterns

    DEFF Research Database (Denmark)

    Bertelsen, Birgitte; Tümer, Zeynep; Ravn, Kirstine

    2011-01-01

    . The reliability of the loci was validated by showing a high correlation between the results obtained by employing the new loci and the AR locus using DNA from 15 females who were informative for all four loci. Altogether, we show that these loci can be applied easily in molecular diagnostic laboratories, either...

  4. Two-step activation of meiosis by the mat1 locus in Schizosaccharomyces pombe

    DEFF Research Database (Denmark)

    Willer, M; Hoffmann, Ulla-Lisbeth; Styrkársdóttir, U

    1995-01-01

    in which the mat1 locus plays two roles in controlling meiosis. In the first instance, the mat1-Pc and mat1-Mc functions are required to produce the mating pheromones and receptors that allow the generation of a pheromone signal. This signal is required to induce the expression of mat1-Pm and mat1-Mm......The mat1 locus is a key regulator of both conjugation and meiosis in the fission yeast Schizosaccharomyces pombe. Two alternative DNA segments of this locus, mat1-P and mat1-M, specify the haploid cell types (Plus and Minus). Each segment includes two genes: mat1-P includes mat1-Pc and mat1-Pm....... This appears to be the major pheromone-dependent step in controlling meiosis since ectopic expression of these genes allows meiosis in the absence of mat1-Pc and mat1-Mc. The mat1-Pm and mat1-Mm products complete the initiation of meiosis by activating transcription of the mei3 gene....

  5. Thermomechanical analyses of phenolic foam reinforced with glass fiber mat

    International Nuclear Information System (INIS)

    Zhou, Jintang; Yao, Zhengjun; Chen, Yongxin; Wei, Dongbo; Wu, Yibing

    2013-01-01

    Highlights: • Over 10% glass fiber was used to reinforce phenolic foam in the shape of glass fiber mat. • Nucleating agents were used together with glass fiber mat and improved tensile strength of phenolic foam by 215.6%. • Nucleating agents lead to a smaller bubble size of phenolic foam. • The glass transition temperature of phenolic foam remained unchanged during the reinforcement. - Abstract: In this paper, thermomechanical analysis (TMA) and dynamic mechanical analysis were employed to study the properties of phenolic foam reinforced with glass fiber mat. Unreinforced phenolic foam was taken as the control sample. Mechanical tests and scanning electron microscopy were performed to confirm the results of TMA. The results show that glass fiber mat reinforcement improves the mechanical performance of phenolic foam, and nucleating agents improve it further. Phenolic foam reinforced with glass fiber mat has a smaller thermal expansion coefficient compared with unreinforced foam. The storage modulus of the reinforced phenolic foam is also higher than that in unreinforced foam, whereas the loss modulus of the former is lower than that of the latter. The glass transition temperature of the phenolic foam matrix remains unchanged during the reinforcement

  6. Critique de la dématérialisation

    OpenAIRE

    Robert , Pascal

    2004-01-01

    International audience; La notion de " dématérialisation " constitue actuellement l'une des pièces maîtresses de l'idéologie de la communication. Or, après enquête, nous constatons que la dématérialisation ne se rencontre ni dans les TIC ni dans les réseaux où se dévoilent en revanche un nouveau mode de matérialisation ainsi qu'un processus de virtualisation par changement d'échelle. Nous nous interrogeons donc sur la fonction sociale et politique que cette notion joue dans les discours qui l...

  7. Storage of yerba maté in controlled atmosphere

    Directory of Open Access Journals (Sweden)

    Sarah Lemos Cogo Prestes

    2014-04-01

    Full Text Available The aim of this study was to evaluate the effect of controlled atmosphere in the change of color, chlorophyll degradation and phenolic compounds concentration in yerba maté thickly ground (“cancheada” and thinly milled (“socada”. Yerba maté samples from the towns of Arvorezinha (RS - Brazil and São Mateus do Sul (PR - Brazil were stored in four levels of oxygen (1, 3, 6 and 20.9kPa of O2 and four levels of carbon dioxide (0, 3, 6 and 18kPa of CO2 and then were analyzed, after nine months of storage. According to the results, the O2 partial pressure reduction decreased the loss of green coloration, kept a higher content of chlorophylls and of total phenolic compounds. In relation to the different levels of CO2, a response as remarkable as O2 was not observed. The yerba maté that was thickly ground (“cancheada” presented a better storage potential than the one thinly milled (“socada” in the storage with O2 and with CO2. The 1kPa of O2 condition kept the yerba maté greener and with a higher content of chlorophylls and of total phenolic compounds after nine months of storage. The CO2 partial pressure kept the yerba maté coloration greener and with a higher content of chlorophylls and of total phenolic compounds, regardless of the level used, in the maté from both cultivation areas.

  8. Phylogenetic stratigraphy in the Guerrero Negro hypersaline microbial mat.

    Science.gov (United States)

    Harris, J Kirk; Caporaso, J Gregory; Walker, Jeffrey J; Spear, John R; Gold, Nicholas J; Robertson, Charles E; Hugenholtz, Philip; Goodrich, Julia; McDonald, Daniel; Knights, Dan; Marshall, Paul; Tufo, Henry; Knight, Rob; Pace, Norman R

    2013-01-01

    The microbial mats of Guerrero Negro (GN), Baja California Sur, Mexico historically were considered a simple environment, dominated by cyanobacteria and sulfate-reducing bacteria. Culture-independent rRNA community profiling instead revealed these microbial mats as among the most phylogenetically diverse environments known. A preliminary molecular survey of the GN mat based on only ∼1500 small subunit rRNA gene sequences discovered several new phylum-level groups in the bacterial phylogenetic domain and many previously undetected lower-level taxa. We determined an additional ∼119,000 nearly full-length sequences and 28,000 >200 nucleotide 454 reads from a 10-layer depth profile of the GN mat. With this unprecedented coverage of long sequences from one environment, we confirm the mat is phylogenetically stratified, presumably corresponding to light and geochemical gradients throughout the depth of the mat. Previous shotgun metagenomic data from the same depth profile show the same stratified pattern and suggest that metagenome properties may be predictable from rRNA gene sequences. We verify previously identified novel lineages and identify new phylogenetic diversity at lower taxonomic levels, for example, thousands of operational taxonomic units at the family-genus levels differ considerably from known sequences. The new sequences populate parts of the bacterial phylogenetic tree that previously were poorly described, but indicate that any comprehensive survey of GN diversity has only begun. Finally, we show that taxonomic conclusions are generally congruent between Sanger and 454 sequencing technologies, with the taxonomic resolution achieved dependent on the abundance of reference sequences in the relevant region of the rRNA tree of life.

  9. Flow of light energy in benthic photosynthetic microbial mats

    Energy Technology Data Exchange (ETDEWEB)

    Al-Najjar, Mohammad Ahmad A.

    2010-12-15

    The work in this thesis demonstrates the assessment of the energy budget inside microbial mat ecosystems, and the factors affecting light utilization efficiency. It presents the first balanced light energy budget for benthic microbial mat ecosystems, and shows how the budget and the spatial distribution of the local photosynthetic efficiencies within the euphotic zone depend on the absorbed irradiance (Jabs). The energy budget was dominated by heat dissipation on the expense of photosynthesis. The maximum efficiency of photosynthesis was at light limiting conditions When comparing three different marine benthic photosynthetic ecosystems (originated from Abu-Dhabi, Arctic, and Exmouth Gulf in Western Australia), differences in the efficiencies were calculated. The results demonstrated that the maximum efficiency depended on mat characteristics affecting light absorption and scattering; such as, photopigments ratio and distribution, and the structural organization of the photosynthetic organisms relative to other absorbing components of the ecosystem (i.e., EPS, mineral particles, detritus, etc.). The maximum efficiency decreased with increasing light penetration depth, and increased with increasing the accessory pigments (phycocyanin and fucoxanthin)/chlorophyll ratio. Spatial heterogeneity in photosynthetic efficiency, pigment distribution, as well as light acclimation in microbial mats originating from different geographical locations was investigated. We used a combined pigment imaging approach (variable chlorophyll fluorescence and hyperspectral imaging), and fingerprinting approach. For each mat, the photosynthetic activity was proportional to the local pigment concentration in the photic zone, but not for the deeper layers and between different mats. In each mat, yield of PSII and E1/2 (light acclimation) generally decreased in parallel with depth, but the gradients in both parameters varied greatly between samples. This mismatch between pigments concentration

  10. Targeting S-adenosylmethionine biosynthesis with a novel allosteric inhibitor of Mat2A

    Energy Technology Data Exchange (ETDEWEB)

    Quinlan, Casey L.; Kaiser, Stephen E.; Bolaños, Ben; Nowlin, Dawn; Grantner, Rita; Karlicek-Bryant, Shannon; Feng, Jun Li; Jenkinson, Stephen; Freeman-Cook, Kevin; Dann, Stephen G.; Wang, Xiaoli; Wells, Peter A.; Fantin, Valeria R.; Stewart, Al E.; Grant, Stephan K. (Pfizer)

    2017-05-29

    S-Adenosyl-L-methionine (SAM) is an enzyme cofactor used in methyl transfer reactions and polyamine biosynthesis. The biosynthesis of SAM from ATP and L-methionine is performed by the methionine adenosyltransferase enzyme family (Mat; EC 2.5.1.6). Human methionine adenosyltransferase 2A (Mat2A), the extrahepatic isoform, is often deregulated in cancer. We identified a Mat2A inhibitor, PF-9366, that binds an allosteric site on Mat2A that overlaps with the binding site for the Mat2A regulator, Mat2B. Studies exploiting PF-9366 suggested a general mode of Mat2A allosteric regulation. Allosteric binding of PF-9366 or Mat2B altered the Mat2A active site, resulting in increased substrate affinity and decreased enzyme turnover. These data support a model whereby Mat2B functions as an inhibitor of Mat2A activity when methionine or SAM levels are high, yet functions as an activator of Mat2A when methionine or SAM levels are low. The ramification of Mat2A activity modulation in cancer cells is also described.

  11. Microbial mat-induced sedimentary structures in siliciclastic sediments

    Indian Academy of Sciences (India)

    This paper addresses macroscopic signatures of microbial mat-related structures within the. 1.6Ga-old Chorhat Sandstone ... Sandstone differentiated in facies superposed one over the other and their respective structural assemblages (b). may be ..... within the classification of primary sedimentary struc- tures; J. Sed. Res.

  12. The Varian MAT-250 mass spectrometer. Steady isotopes laboratory

    International Nuclear Information System (INIS)

    Hernandez M, V.; Tavera D, M.L.

    1997-01-01

    This work treats over the performance and applications of the Varian Mat-250 mass spectrometer which is in the environmental isotope laboratory. It can be applied over topics such as: ions formation, acceleration and collimation, ions separation, ions detection, data transformation, sampling, δ notation. (Author)

  13. The Ububele Baby Mat Service – A primary preventative mental ...

    African Journals Online (AJOL)

    The Ububele Baby Mat Service is a community-based, parent–infant mental health intervention offered at five primary health care clinics in Alexandra Township, in Johannesburg. The aim of the intervention is to promote healthy caregiver-infant attachments. There has been a steady increase in the number of mother-baby ...

  14. Evaluation of the WavTrac Expeditionary Mobility Matting System

    Science.gov (United States)

    2017-04-01

    Dr. Timothy W. Rushing was Chief, APB; Dr. Gordon W. McMahon was Chief, ESMD; and Nicholas Boone was the Technical Director for Force Projection...were tan in color and had a nonskid material applied to the wearing surface. Typical mat dimensions were 12 ft, 2 in. wide by 48 ft, 6 in. long

  15. Social yoga mats: reinforcing synergy between physical and social activity

    DEFF Research Database (Denmark)

    Nagargoje, Arun; Sokoler, Tomas; Maybach, Karl

    2011-01-01

    This paper discusses our early research into the design space for digital technologies that extend the existing synergistic relationship between physical and social activity from fitness centers to the home. We focus on yoga activity for senior citizens and explore the concept of social yoga mats...

  16. Matting of Hair Due to Halo-egg Shampoo

    Directory of Open Access Journals (Sweden)

    Z M Mani

    1983-01-01

    Full Text Available A case of hair matting in an 18 year old female is reported. The hair got densely entangled immediately after washing the hair with ′Halo Egg′ shampoo. The hair was disentangled completely after prolonged dipping of the hair in arachis oil frr 5 days.

  17. Diversity of nitrogen-fixing bacteria in cyanobacterial mats

    NARCIS (Netherlands)

    Severin, I.; Acinas, S.G.; Stal, L.J.

    2010-01-01

    The structure of the microbial community and the diversity of the functional gene for dinitrogenase reductase and its transcripts were investigated by analyzing >1400 16S rRNA gene and nifH sequences from two microbial mats situated in the intertidal zone of the Dutch barrier island Schiermonnikoog.

  18. Response of cyanobacterial mats to nutrient and salinity changes

    Czech Academy of Sciences Publication Activity Database

    Rejmánková, E.; Komárková, Jaroslava

    2005-01-01

    Roč. 83, č. 2 (2005), s. 87-107 ISSN 0304-3770. [INTECOL International Wetlands Conference /7./. Utrecht, 25.07.2004-30.7.2004] Grant - others:NSF(US) 0089211 Institutional research plan: CEZ:AV0Z60170517 Keywords : cyanobacterial mats * Belize * P-N impact Subject RIV: EH - Ecology, Behaviour Impact factor: 1.344, year: 2005

  19. Advanced HVAC modeling with FemLab/Simulink/MatLab

    NARCIS (Netherlands)

    Schijndel, van A.W.M.

    2003-01-01

    The combined MatLab toolboxes FemLab and Simulink are evaluated as solvers for HVAC problems based on partial differential equations (PDEs). The FemLab software is designed to simulate systems of coupled PDEs, 1-D, 2-D or 3-D, nonlinear and time dependent. In order to show how the program works, a

  20. Coastal Microbial Mat Diversity along a Natural Salinity Gradient

    NARCIS (Netherlands)

    Bolhuis, H.; Fillinger, L.; Stal, L.J.

    2013-01-01

    The North Sea coast of the Dutch barrier island of Schiermonnikoog is covered by microbial mats that initiate a succession of plant communities that eventually results in the development of a densely vegetated salt marsh. The North Sea beach has a natural elevation running from the low water mark to

  1. GWAS identifies four novel eosinophilic esophagitis loci

    NARCIS (Netherlands)

    Sleiman, Patrick M. A.; Wang, Mei-Lun; Cianferoni, Antonella; Aceves, Seema; Gonsalves, Nirmala; Nadeau, Kari; Bredenoord, Albert J.; Furuta, Glenn T.; Spergel, Jonathan M.; Hakonarson, Hakon

    2014-01-01

    Eosinophilic esophagitis (EoE) is an allergic disorder characterized by infiltration of the oesophagus with eosinophils. We had previously reported association of the TSLP/WDR36 locus with EoE. Here we report genome-wide significant associations at four additional loci; c11orf30 and STAT6, which

  2. Matérn-based nonstationary cross-covariance models for global processes

    KAUST Repository

    Jun, Mikyoung

    2014-01-01

    -covariance models, based on the Matérn covariance model class, that are suitable for describing prominent nonstationary characteristics of the global processes. In particular, we seek nonstationary versions of Matérn covariance models whose smoothness parameters

  3. Two-step activation of meiosis by the mat1 locus in Schizosaccharomyces pombe

    DEFF Research Database (Denmark)

    Willer, M; Hoffmann, Ulla-Lisbeth; Styrkársdóttir, U

    1995-01-01

    of meiosis is based largely on indirect observations, and a more precise investigation of these events was required to define the interaction between the mat1 genes. Here we resolve this issue using synthetic pheromones and P/M strains with mutations in either mat1-Pc or mat1-Mc. Our results suggest a model...... in which the mat1 locus plays two roles in controlling meiosis. In the first instance, the mat1-Pc and mat1-Mc functions are required to produce the mating pheromones and receptors that allow the generation of a pheromone signal. This signal is required to induce the expression of mat1-Pm and mat1-Mm...

  4. The Varian MAT-250 mass spectrometer. Steady isotopes laboratory; Espectrometro de masas Varian MAT-250. Laboratorio de isotopos estables

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez M, V.; Tavera D, M.L. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    This work treats over the performance and applications of the Varian Mat-250 mass spectrometer which is in the environmental isotope laboratory. It can be applied over topics such as: ions formation, acceleration and collimation, ions separation, ions detection, data transformation, sampling, {delta} notation. (Author)

  5. Comment on "Performance of a spin based insulated gate field effect transistor" [cond-mat/0603260] [cond-mat/0603260

    OpenAIRE

    Bandyopadhyay, S.; Cahay, M.

    2006-01-01

    In a recent e-print [cond-mat/0603260] Hall and Flatte claim that a particular spin based field effect transistor (SPINFET), which they have analyzed, will have a lower threshold voltage, lower switching energy and lower leakage current than a comparable metal oxide semiconductor field effect transistor (MOSFET). Here, we show that all three claims of HF are invalid.

  6. Toolbox for the Modeling and Analysis of Thermodynamic Systems (T-MATS) Users' Workshop Presentations

    Science.gov (United States)

    Litt, Jonathan S. (Compiler)

    2018-01-01

    NASA Glenn Research Center hosted a Users' Workshop on the Toolbox for the Modeling and Analysis of Thermodynamic Systems (T-MATS) on August 21, 2017. The objective of this workshop was to update the user community on the latest features of T-MATS, and to provide a forum to present work performed using T-MATS. Presentations highlighted creative applications and the development of new features and libraries, and emphasized the flexibility and simulation power of T-MATS.

  7. Regulation of electron transfer processes affects phototrophic mat structure and activity

    OpenAIRE

    Ha, Phuc T.; Renslow, Ryan S.; Atci, Erhan; Reardon, Patrick N.; Lindemann, Stephen R.; Fredrickson, James K.; Call, Douglas R.; Beyenal, Haluk

    2015-01-01

    Phototrophic microbial mats are among the most diverse ecosystems in nature. These systems undergo daily cycles in redox potential caused by variations in light energy input and metabolic interactions among the microbial species. In this work, solid electrodes with controlled potentials were placed under mats to study the electron transfer processes between the electrode and the microbial mat. The phototrophic microbial mat was harvested from Hot Lake, a hypersaline, epsomitic lake located ne...

  8. Flakeboard thickness swelling. Part I, Stress relaxation in a flakeboard mat

    Science.gov (United States)

    R. L. Geimer; J. H. Kwon; J. Bolton

    1998-01-01

    The steam injection schedule best suited for dimensionally stabilizing a flake mat is one in which steam treatment is initiated before the press is closed and is continued at least until the mat attains target thickness. Experiments showed that resinless mats treated with 20 sec of steam at 600 kPa had maximum thickness swelling of 205% compared to 350% for resinless...

  9. Genetic variation of twenty autosomal STR loci and evaluate the ...

    African Journals Online (AJOL)

    SAM

    2014-03-12

    Mar 12, 2014 ... the second objective of the study was to evaluate the importance of these loci for forensic genetic purposes. ... of discrimination values for all tested loci was from 75 to 96%; therefore, those loci can be safely used to establish a ..... lists the frequency distribution of individual alleles within a given genetic ...

  10. Aspects of the ecology of mat-forming lichens

    Directory of Open Access Journals (Sweden)

    P. D. Crittenden

    2000-03-01

    Full Text Available Lichen species in the genera Cladonia (subgenus Cladina, Cetraria, Stereocaulon and Alectoria are important vegetation components on well-drained terrain and on elevated micro-sites in peatlands in boreal-Arctic regions. These lichens often form closed mats, the component thalli in which grow vertically upwards at the apices and die off in the older basal regions; they are therefore only loosely attached to the underlying soil. This growth habit is relatively unusual in lichens being found in <0.5% of known species. It might facilitate internal nutrienr recycling and higher growth rates and, together with the production of allelochemicals, it might underlie the considerable ecological success of mat-forming lichens; experiments to critically assess the importance of these processes are required. Mat-forming lichens can constitute in excess of 60% of the winter food intake of caribou and reindeer. Accordingly there is a pressing need for data on lichen growth rates, measured as mass increment, in order to help determine the carrying capacity of winter ranges for rhese herbivores and to better predict recovery rates following grazing. Trampling during the snow-free season fragments lichen thalli; mat-forming lichens regenerate very successfully from thallus fragments provided trampling does nor re-occur. Frequent recurrence of trampling creates disturbed habitats from which lichens will rapidly become eliminated consistent with J.P. Grime's CSR strategy theory. Such damage to lichen ground cover has occurred where reindeer or caribou are unable to migrate away from their winter range such as on small islands or where political boundaries have been fenced; it can also occur on summer range that contains a significant lichen component and on winter range where numbers of migrarory animals become excessive. Species of Stereocaulon, and other genera that contain cyanobacteria (most notably Peltigera and Nephroma, are among the principal agents of

  11. Radiation-induced mutation at minisatellite loci

    International Nuclear Information System (INIS)

    Dubrova, Y.E.; Nesterov, V.N.; Krouchinsky, N.G.

    1997-01-01

    We are studying the radiation-induced increase of mutation rate in minisatellite loci in mice and humans. Minisatellite mutations were scored by multilocus DNA fingerprint analysis in the progeny of γ-irradiated and non-irradiated mice. The frequency of mutation in offspring of irradiated males was 1.7 higher that in the control group. Germline mutation at human minisatellite loci was studied among children born in heavily polluted areas of the Mogilev district of Belarus after the Chernobyl accident and in a control population. The frequency of mutation assayed both by DNA fingerprinting and by eight single locus probes was found to be two times higher in the exposed families than in the control group. Furthermore, mutation rate was correlated with the parental radiation dose for chronic exposure 137 Cs, consistent with radiation-induction of germline mutation. The potential use of minisatellites in monitoring germline mutation in humans will be discussed

  12. Virulence attributes and hyphal growth of C. neoformans are quantitative traits and the MATalpha allele enhances filamentation.

    Directory of Open Access Journals (Sweden)

    Xiaorong Lin

    2006-11-01

    Full Text Available Cryptococcus neoformans is a fungal human pathogen with a bipolar mating system. It undergoes a dimorphic transition from a unicellular yeast to hyphal filamentous growth during mating and monokaryotic fruiting. The traditional sexual cycle that leads to the production of infectious basidiospores involves cells of both alpha and a mating type. Monokaryotic fruiting is a modified form of sexual reproduction that involves cells of the same mating type, most commonly alpha, which is the predominant mating type in both the environment and clinical isolates. However, some a isolates can also undergo monokaryotic fruiting. To determine whether mating type and other genetic loci contribute to the differences in fruiting observed between alpha and a cells, we applied quantitative trait loci (QTL mapping to an inbred population of F2 progeny. We discovered that variation in hyphal length produced during fruiting is a quantitative trait resulting from the combined effects of multiple genetic loci, including the mating type (MAT locus. Importantly, the alpha allele of the MAT locus enhanced hyphal growth compared with the a allele. Other virulence traits, including melanization and growth at 39 degrees C, also are quantitative traits that share a common QTL with hyphal growth. The Mac1 transcription factor, encoded in this common QTL, regulates copper homeostasis. MAC1 allelic differences contribute to phenotypic variation, and mac1Delta mutants exhibit defects in filamentation, melanin production, and high temperature growth. Further characterization of these QTL regions will reveal additional quantitative trait genes controlling biological processes central to fungal development and pathogenicity.

  13. Novel genetic loci associated with hippocampal volume

    OpenAIRE

    Hibar, Derrek P.; Adams, Hieab H. H.; Jahanshad, Neda; Chauhan, Ganesh; Stein, Jason L.; Hofer, Edith; Renteria, Miguel E.; Bis, Joshua C.; Arias-Vasquez, Alejandro; Ikram, M. Kamran; Desrivieres, Sylvane; Vernooij, Meike W.; Abramovic, Lucija; Alhusaini, Saud; Amin, Najaf

    2017-01-01

    International audience; The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal ...

  14. The loci controlling plasticity in flax

    Directory of Open Access Journals (Sweden)

    Bickel CL

    2012-02-01

    Full Text Available Cory L Bickel, Marshall Lukacs, Christopher A CullisCase Western Reserve University, Cleveland OH, USAAbstract: Flax undergoes heritable genomic changes in response to nutrient stress, including changes in total DNA content, rDNA copy number variation, and the appearance of Linum Insertion Sequence 1 (LIS-1. The nature of the genomic changes suggests a very different mechanism, which is not yet understood, from that of other DNA changes in response to stress, such as the activation of transposable elements. To identify the genes that control genomic changes in response to stress in flax, reciprocal crosses were made between a responsive flax line, Stormont cirrus, and an unresponsive line, Bethune. The ability of the F2 generation (from selfed F1 plants to respond to nutrient stress was assayed using the insertion of LIS-1 as the criteria for responsiveness. Twenty-nine out of 89 F2s responded at 5 weeks, suggesting that 3-4 dominant loci were all necessary for early LIS-1 insertion. Seventy out of 76 responded at 10 weeks, indicating two dominant loci independently capable of initiating LIS-1 insertion under prolonged nutrient stress. F1 plants and their progeny with either P1 or Bethune as the maternal parent were capable of responding with LIS-1 insertion, indicating that LIS-1 insertion is under nuclear genetic control and does not involve maternal factors. Thus, a small number of loci within the genome of Stormont cirrus appear to control the ability to respond to nutrient stress with LIS-1 insertion. A genetic map of the flax genome is currently under construction, and will be used to identify these loci within the genome.Keywords: nutrient stress, genomic plasticity, flax, Linum usitatissimum, LIS-1 

  15. Thermodynamics and phase transformations: the selected works of Mats Hillert

    International Nuclear Information System (INIS)

    Agren, J.; Brechet, Y.; Hutchinson, Ch.; Purdy, G.

    2006-01-01

    For over half a century, Mats Hillert has contributed greatly to the science of materials. He is widely known and respected as an innovator and an educator, a scientist with an enormous breadth of interest and depth of insight. In acknowledgment of his many contributions, a conference was held in Stockholm in December 2004 to mark his eightieth birthday. This volume was conceived prior to, and publicly announced during the conference. The difficult choice of twenty-four papers from a publication list of more than three hundred was carried out in consultation with Mats. He also suggested or approved the scientists who would be invited to write a brief introduction to each paper. A brief reading of the topics of the selected papers and their introductions reveals something of their range and depth. Several early selections (for example, those on 'The Role of Interfacial Energy during Solid State Phase Transformations', and 'A Solid-Solution Model for Inhomogeneous Systems') contained seminal material that established Mats as a leading figure in the study of phase transformations in solids. Others established his presence in the areas of solidification and computational thermodynamics. A review of his full publication list shows that he has consistently built upon those early foundational papers, and maintained a dominant position in those fields. Although many of his contributions have been of a theoretical nature, he has always maintained a close contact with experiment, and indeed, he has designed numerous critical experiments. This volume represents a judicious sampling of Mats Hillert's extensive body of work; it is necessarily incomplete, but it is hoped and expected that it will prove useful to students of materials science and engineering at all levels, and that it will inspire the further study and appreciation of his many contributions. (authors)

  16. Accuracy of Jump-Mat Systems for Measuring Jump Height.

    Science.gov (United States)

    Pueo, Basilio; Lipinska, Patrycja; Jiménez-Olmedo, José M; Zmijewski, Piotr; Hopkins, Will G

    2017-08-01

    Vertical-jump tests are commonly used to evaluate lower-limb power of athletes and nonathletes. Several types of equipment are available for this purpose. To compare the error of measurement of 2 jump-mat systems (Chronojump-Boscosystem and Globus Ergo Tester) with that of a motion-capture system as a criterion and to determine the modifying effect of foot length on jump height. Thirty-one young adult men alternated 4 countermovement jumps with 4 squat jumps. Mean jump height and standard deviations representing technical error of measurement arising from each device and variability arising from the subjects themselves were estimated with a novel mixed model and evaluated via standardization and magnitude-based inference. The jump-mat systems produced nearly identical measures of jump height (differences in means and in technical errors of measurement ≤1 mm). Countermovement and squat-jump height were both 13.6 cm higher with motion capture (90% confidence limits ±0.3 cm), but this very large difference was reduced to small unclear differences when adjusted to a foot length of zero. Variability in countermovement and squat-jump height arising from the subjects was small (1.1 and 1.5 cm, respectively, 90% confidence limits ±0.3 cm); technical error of motion capture was similar in magnitude (1.7 and 1.6 cm, ±0.3 and ±0.4 cm), and that of the jump mats was similar or smaller (1.2 and 0.3 cm, ±0.5 and ±0.9 cm). The jump-mat systems provide trustworthy measurements for monitoring changes in jump height. Foot length can explain the substantially higher jump height observed with motion capture.

  17. Matted-fiber divertor tagets for sputter resistance

    International Nuclear Information System (INIS)

    Gierszewski, P.J.; Todreas, N.E.; Mikic, B.; Yang, T.F.

    1981-06-01

    Reductions in net sputtering yields can be obtained by altering the surface topography to maximize redeposition of sputtered atoms. A simple analysis is used to indicate a potential reduction by a factor of 2 to 5 for matted fiber divertor targets, relatively independent of incident, reflected and sputtered atom distributions. The fiber temperature is also shown to be acceptable, even up to 10 MW/m 2 , for reasonably combinations of materials, fiber diameter and fiber spacing

  18. Alpha Matting with KL-Divergence Based Sparse Sampling.

    Science.gov (United States)

    Karacan, Levent; Erdem, Aykut; Erdem, Erkut

    2017-06-22

    In this paper, we present a new sampling-based alpha matting approach for the accurate estimation of foreground and background layers of an image. Previous sampling-based methods typically rely on certain heuristics in collecting representative samples from known regions, and thus their performance deteriorates if the underlying assumptions are not satisfied. To alleviate this, we take an entirely new approach and formulate sampling as a sparse subset selection problem where we propose to pick a small set of candidate samples that best explains the unknown pixels. Moreover, we describe a new dissimilarity measure for comparing two samples which is based on KLdivergence between the distributions of features extracted in the vicinity of the samples. The proposed framework is general and could be easily extended to video matting by additionally taking temporal information into account in the sampling process. Evaluation on standard benchmark datasets for image and video matting demonstrates that our approach provides more accurate results compared to the state-of-the-art methods.

  19. Phenotypic variation and characterization of mutant matting in shiitake

    International Nuclear Information System (INIS)

    Ibrahim Mahmood; Azhar Mohamad

    2016-01-01

    Shiitake (Lentinula edodes) is an edible mushroom that has many uses such as: pharmaceutical, nutraceutical and cosmeceutical industries. In this study, we will induce Shiitake to create the genetic variation via exposing the spores of shiitake to gamma (γ) ray at different doses (0-700 Gy) then make the matting between two different monokaryon mycelium (MM). potato dextrose agar (PDA), this media will be used for spore germination and monokaryon mycelium subculturing during this study. The compatibility of the matting will be observed macroscopically (observing on the plates of PDA) and microscopically (by observing the clamps test under the microscope (Olympus brand)). The finding of this study, there is no significant changing in the growth performance of irradiated monokaryon mycelium in comparing with non-irradiated mycelium. From 108 matting only 15 were compatibles. This study, the physical mutagen will be used followed by mating as a normal stage of life cycle for creating potential strain of shiitake with alteration in phenotypic characterization of dikaryon mycelium (DM) as a compatible mating for two MM. (author)

  20. Simulated Carbon Cycling in a Model Microbial Mat.

    Science.gov (United States)

    Decker, K. L.; Potter, C. S.

    2006-12-01

    We present here the novel addition of detailed organic carbon cycling to our model of a hypersaline microbial mat ecosystem. This ecosystem model, MBGC (Microbial BioGeoChemistry), simulates carbon fixation through oxygenic and anoxygenic photosynthesis, and the release of C and electrons for microbial heterotrophs via cyanobacterial exudates and also via a pool of dead cells. Previously in MBGC, the organic portion of the carbon cycle was simplified into a black-box rate of accumulation of simple and complex organic compounds based on photosynthesis and mortality rates. We will discuss the novel inclusion of fermentation as a source of carbon and electrons for use in methanogenesis and sulfate reduction, and the influence of photorespiration on labile carbon exudation rates in cyanobacteria. We will also discuss the modeling of decomposition of dead cells and the ultimate release of inorganic carbon. The detailed modeling of organic carbon cycling is important to the accurate representation of inorganic carbon flux through the mat, as well as to accurate representation of growth models of the heterotrophs under different environmental conditions. Because the model ecosystem is an analog of ancient microbial mats that had huge impacts on the atmosphere of early earth, this MBGC can be useful as a biological component to either early earth models or models of other planets that potentially harbor life.

  1. Hydroponic root mats for wastewater treatment-a review.

    Science.gov (United States)

    Chen, Zhongbing; Cuervo, Diego Paredes; Müller, Jochen A; Wiessner, Arndt; Köser, Heinz; Vymazal, Jan; Kästner, Matthias; Kuschk, Peter

    2016-08-01

    Hydroponic root mats (HRMs) are ecotechnological wastewater treatment systems where aquatic vegetation forms buoyant filters by their dense interwoven roots and rhizomes, sometimes supported by rafts or other floating materials. A preferential hydraulic flow is created in the water zone between the plant root mat and the bottom of the treatment system. When the mat touches the bottom of the water body, such systems can also function as HRM filter; i.e. the hydraulic flow passes directly through the root zone. HRMs have been used for the treatment of various types of polluted water, including domestic wastewater; agricultural effluents; and polluted river, lake, stormwater and groundwater and even acid mine drainage. This article provides an overview on the concept of applying floating HRM and non-floating HRM filters for wastewater treatment. Exemplary performance data are presented, and the advantages and disadvantages of this technology are discussed in comparison to those of ponds, free-floating plant and soil-based constructed wetlands. Finally, suggestions are provided on the preferred scope of application of HRMs.

  2. Determination of 210Po in tea, mat and their infusions and its annual intake by Syrians

    International Nuclear Information System (INIS)

    Al-Masri, M.S.; Nashawati, A.; Amin, Y.; Al-Akel, B.

    2004-01-01

    Polonium-210 was determined in 34 kinds of imported tea and 9 kinds of mat collected from the Syrian local market. The 210 Po concentration was found to vary from 5.5 to 39 Bq x kg -1 and 47 to 82 Bq x kg -1 in tea and mat samples, respectively. In addition 210 Po was also determined in tea and mat infusions where different infusion conditions have been examined: amount, temperature and infusion time. The results have shown that the amount of 210 Po transferred from tea and mat leaves to the aqueous extract ranged from 9 to 21% and 3 to 15%, respectively. The annual intake of 210 Po by Syrians due to tea consumption and mat infusions was calculated and found to be 9 Bq and 151 Bq for tea and mat respectively: washing of mat with warm water is recommended before preparation the infusions to decrease the annual intake of 210 Po. (author)

  3. Mucoadhesive electrospun chitosan-based nanofibre mats for dental caries prevention.

    Science.gov (United States)

    Samprasit, Wipada; Kaomongkolgit, Ruchadaporn; Sukma, Monrudee; Rojanarata, Theerasak; Ngawhirunpat, Tanasait; Opanasopit, Praneet

    2015-03-06

    The mucoadhesive electrospun nanofibre mats were developed using chitosan (CS) and thiolated chitosan (CS-SH) as mucoadhesive polymers. Garcinia mangostana (GM) extract was incorporated into nanofibre mats. The antibacterial activity in the single and combined agents was evaluated against dental caries pathogens. The morphology of mats was observed using SEM. The mats were evaluated for GM extract amount, mucoadhesion, in vitro release, antibacterial activity and cytotoxicity. The mucoadhesion and antibacterial activity were determined in healthy human volunteers. The prepared mats were in nanoscale with good physical and mucoadhesive properties. The CS-SH caused the higher mucoadhesion. All mats rapidly released active substances, which had the synergistic antibacterial activity. In addition, the reduction of bacteria and good mucoadhesion in the oral cavity occurred without cytotoxicity. The results suggest that mats have the potential to be mucoadhesive dosage forms to maintain oral hygiene by reducing the bacterial growth that causes the dental caries. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Studying Microbial Mat Functioning Amidst "Unexpected Diversity": Methodological Approaches and Initial Results from Metatranscriptomes of Mats Over Diel cycles, iTags from Long Term Manipulations, and Biogeochemical Cycling in Simplified Microbial Mats Constructed from Cultures

    Science.gov (United States)

    Bebout, B.; Bebout, L. E.; Detweiler, A. M.; Everroad, R. C.; Lee, J.; Pett-Ridge, J.; Weber, P. K.

    2014-12-01

    Microbial mats are famously amongst the most diverse microbial ecosystems on Earth, inhabiting some of the most inclement environments known, including hypersaline, dry, hot, cold, nutrient poor, and high UV environments. The high microbial diversity of microbial mats makes studies of microbial ecology notably difficult. To address this challenge, we have been using a combination of metagenomics, metatranscriptomics, iTags and culture-based simplified microbial mats to study biogeochemical cycling (H2 production, N2 fixation, and fermentation) in microbial mats collected from Elkhorn Slough, Monterey Bay, California. Metatranscriptomes of microbial mats incubated over a diel cycle have revealed that a number of gene systems activate only during the day in Cyanobacteria, while the remaining appear to be constitutive. The dominant cyanobacterium in the mat (Microcoleus chthonoplastes) expresses several pathways for nitrogen scavenging undocumented in cultured strains, as well as the expression of two starch storage and utilization cycles. Community composition shifts in response to long term manipulations of mats were assessed using iTags. Changes in community diversity were observed as hydrogen fluxes increased in response to a lowering of sulfate concentrations. To produce simplified microbial mats, we have isolated members of 13 of the 15 top taxa from our iTag libraries into culture. Simplified microbial mats and simple co-cultures and consortia constructed from these isolates reproduce many of the natural patterns of biogeochemical cycling in the parent natural microbial mats, but against a background of far lower overall diversity, simplifying studies of changes in gene expression (over the short term), interactions between community members, and community composition changes (over the longer term), in response to environmental forcing.

  5. A revised nomenclature for transcribed human endogenous retroviral loci

    Science.gov (United States)

    2011-01-01

    Background Endogenous retroviruses (ERVs) and ERV-like sequences comprise 8% of the human genome. A hitherto unknown proportion of ERV loci are transcribed and thus contribute to the human transcriptome. A small proportion of these loci encode functional proteins. As the role of ERVs in normal and diseased biological processes is not yet established, transcribed ERV loci are of particular interest. As more transcribed ERV loci are likely to be identified in the near future, the development of a systematic nomenclature is important to ensure that all information on each locus can be easily retrieved. Results Here we present a revised nomenclature of transcribed human endogenous retroviral loci that sorts loci into groups based on Repbase classifications. Each symbol is of the format ERV + group symbol + unique number. Group symbols are based on a mixture of Repbase designations and well-supported symbols used in the literature. The presented guidelines will allow newly identified loci to be easily incorporated into the scheme. Conclusions The naming system will be employed by the HUGO Gene Nomenclature Committee for naming transcribed human ERV loci. We hope that the system will contribute to clarifying a certain aspect of a sometimes confusing nomenclature for human endogenous retroviruses. The presented system may also be employed for naming transcribed loci of human non-ERV repeat loci. PMID:21542922

  6. Rigid Polyurethane Foam Thermal Insulation Protected with Mineral Intumescent Mat

    Directory of Open Access Journals (Sweden)

    Kirpluks Mikelis

    2014-12-01

    Full Text Available One of the biggest disadvantages of rigid polyurethane (PU foams is its low thermal resistance, high flammability and high smoke production. Greatest advantage of this thermal insulation material is its low thermal conductivity (λ, which at 18-28 mW/(m•K is superior to other materials. To lower the flammability of PU foams, different flame retardants (FR are used. Usually, industrially viable are halogenated liquid FRs but recent trends in EU regulations show that they are not desirable any more. Main concern is toxicity of smoke and health hazard form volatiles in PU foam materials. Development of intumescent passive fire protection for foam materials would answer problems with flammability without using halogenated FRs. It is possible to add expandable graphite (EG into PU foam structure but this increases the thermal conductivity greatly. Thus, the main advantage of PU foam is lost. To decrease the flammability of PU foams, three different contents 3%; 9% and 15% of EG were added to PU foam formulation. Sample with 15% of EG increased λ of PU foam from 24.0 to 30.0 mW/(m•K. This paper describes the study where PU foam developed from renewable resources is protected with thermally expandable intumescent mat from Technical Fibre Products Ltd. (TFP as an alternative to EG added into PU material. TFP produces range of mineral fibre mats with EG that produce passive fire barrier. Two type mats were used to develop sandwich-type PU foams. Also, synergy effect of non-halogenated FR, dimethyl propyl phosphate and EG was studied. Flammability of developed materials was assessed using Cone Calorimeter equipment. Density, thermal conductivity, compression strength and modulus of elasticity were tested for developed PU foams. PU foam morphology was assessed from scanning electron microscopy images.

  7. Solution-blown nanofiber mats from fish sarcoplasmic protein

    DEFF Research Database (Denmark)

    Sett, S.; Boutrup Stephansen, Karen; Yarin, A.L.

    2016-01-01

    In the present work, solution-blowing was adopted to form nanofibers from fish sarcoplasmic proteins (FSPs). Nanofiber mats containing different weight ratios (up to 90/10) of FSP in the FSP/nylon 6 blended nanofibers were formed from formic acid solutions, and compared to electrospun fibers made...... that the production rate of solution-blowing was increased 30-fold in relation to electrospinning. Overall, this study reveals FSP as an interesting biopolymeric alternative to synthetic polymers, and the introduction of FSP to nylon 6 provides a composite with controlled properties....

  8. Siwonhan-mat: The third taste of Korean foods

    OpenAIRE

    Soon Ah Kang; Hyun Ji Oh; Dai Ja Jang; Min Jung Kim; Dae Young Kwon

    2016-01-01

    Background: Smell and taste are frequently referenced senses when describing flavors of food. In addition to these two senses, Koreans have regarded that there is another sense of taste experienced through the body. This third sense, siwonhan-mat (시원한 맛), describes the sensation of the body including the tongue, stomach, and intestines when eating. While smell and taste play an important role in the enjoyment of food, it is also crucial to evaluate what your body can experience from eating. I...

  9. Determination of triiodothyronine using RIA-Mat T3 kit

    International Nuclear Information System (INIS)

    Hara, Masao

    1975-01-01

    A RIA-Mat T 3 kit was used for an in vitro measurement of triiodothyronine in serum. A resin strip was utilized to absorb free triiodothyronine after the serum was incubated with antibody against triiodothyronine. This test was easy to manipulate and the reproducibility test with same sera, dilution test, and recovery test were also satisfactory. The normal range of triiodothyronine determined with this test kit was 119 +- 40 ng/dl using 50 test sera. Ninety sera with various thyroid diseases were also determined. (auth.)

  10. Enhancement of the in-plane shear properties of carbon fiber composites containing carbon nanotube mats

    Science.gov (United States)

    Kim, Hansang

    2015-01-01

    The in-plane shear property of carbon fiber laminates is one of the most important structural features of aerospace and marine structures. Fiber-matrix debonding caused by in-plane shear loading is the major failure mode of carbon fiber composites because of the stress concentration at the interfaces. In this study, carbon nanotube mats (CNT mat) were incorporated in two different types of carbon fiber composites. For the case of woven fabric composites, mechanical interlocking between the CNTs and the carbon fibers increased resistance to shear failure. However, not much improvement was observed for the prepreg composites as a result of incorporation of the CNT mats. The reinforcement mechanism of the CNT mat layer was investigated by a fractographic study using scanning electron microscopy. In addition, the CNT mat was functionalized by three different methods and the effectiveness of the functionalization methods was determined and the most appropriate functionalization method for the CNT mat was air oxidation.

  11. Electrospun magnetic nanofibre mats – A new bondable biomaterial using remotely activated magnetic heating

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Yi [Department of Materials Engineering, University of British Columbia, Vancouver (Canada); Key Laboratory of Science & Technology of Eco-Textile, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai (China); Leung, Victor; Yuqin Wan, Lynn [Department of Materials Engineering, University of British Columbia, Vancouver (Canada); Dutz, Silvio [Institut für Biomedizinische Technik und Informatik, Technische Universität Ilmenau (Germany); Department of Nano Biophotonics, Leibniz Institute of Photonic Technology, Jena (Germany); Ko, Frank K., E-mail: frank.ko@ubc.ca [Department of Materials Engineering, University of British Columbia, Vancouver (Canada); Häfeli, Urs O., E-mail: urs.hafeli@ubc.ca [Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver (Canada)

    2015-04-15

    A solvothermal process was adopted to produce hydrophilic magnetite (Fe{sub 3}O{sub 4}) nanoparticles which were subsequently emulsified with a chloroform/methanol (70/30 v/v) solution of poly(caprolactone) (PCL) and then electrospun into a 0.2 mm thick PCL mat. The magnetic heating of the mats at a field amplitude of 25 kA/m and frequency of 400 kHz exhibited promising efficiency for magnetic hyperthermia, with a specific absorption rate of about 40 W/g for the magnetic mat. The produced heat was used to melt the magnetic mat onto the surrounding non-magnetic polymer mat from within, without destroying the nanostructure of the non-magnetic polymer more than 0.5 mm away. Magnetic nanofibre mats might thus be useful for internal heat sealing applications, and potentially also for thermotherapy.

  12. Novel genetic loci associated with hippocampal volume.

    Science.gov (United States)

    Hibar, Derrek P; Adams, Hieab H H; Jahanshad, Neda; Chauhan, Ganesh; Stein, Jason L; Hofer, Edith; Renteria, Miguel E; Bis, Joshua C; Arias-Vasquez, Alejandro; Ikram, M Kamran; Desrivières, Sylvane; Vernooij, Meike W; Abramovic, Lucija; Alhusaini, Saud; Amin, Najaf; Andersson, Micael; Arfanakis, Konstantinos; Aribisala, Benjamin S; Armstrong, Nicola J; Athanasiu, Lavinia; Axelsson, Tomas; Beecham, Ashley H; Beiser, Alexa; Bernard, Manon; Blanton, Susan H; Bohlken, Marc M; Boks, Marco P; Bralten, Janita; Brickman, Adam M; Carmichael, Owen; Chakravarty, M Mallar; Chen, Qiang; Ching, Christopher R K; Chouraki, Vincent; Cuellar-Partida, Gabriel; Crivello, Fabrice; Den Braber, Anouk; Doan, Nhat Trung; Ehrlich, Stefan; Giddaluru, Sudheer; Goldman, Aaron L; Gottesman, Rebecca F; Grimm, Oliver; Griswold, Michael E; Guadalupe, Tulio; Gutman, Boris A; Hass, Johanna; Haukvik, Unn K; Hoehn, David; Holmes, Avram J; Hoogman, Martine; Janowitz, Deborah; Jia, Tianye; Jørgensen, Kjetil N; Karbalai, Nazanin; Kasperaviciute, Dalia; Kim, Sungeun; Klein, Marieke; Kraemer, Bernd; Lee, Phil H; Liewald, David C M; Lopez, Lorna M; Luciano, Michelle; Macare, Christine; Marquand, Andre F; Matarin, Mar; Mather, Karen A; Mattheisen, Manuel; McKay, David R; Milaneschi, Yuri; Muñoz Maniega, Susana; Nho, Kwangsik; Nugent, Allison C; Nyquist, Paul; Loohuis, Loes M Olde; Oosterlaan, Jaap; Papmeyer, Martina; Pirpamer, Lukas; Pütz, Benno; Ramasamy, Adaikalavan; Richards, Jennifer S; Risacher, Shannon L; Roiz-Santiañez, Roberto; Rommelse, Nanda; Ropele, Stefan; Rose, Emma J; Royle, Natalie A; Rundek, Tatjana; Sämann, Philipp G; Saremi, Arvin; Satizabal, Claudia L; Schmaal, Lianne; Schork, Andrew J; Shen, Li; Shin, Jean; Shumskaya, Elena; Smith, Albert V; Sprooten, Emma; Strike, Lachlan T; Teumer, Alexander; Tordesillas-Gutierrez, Diana; Toro, Roberto; Trabzuni, Daniah; Trompet, Stella; Vaidya, Dhananjay; Van der Grond, Jeroen; Van der Lee, Sven J; Van der Meer, Dennis; Van Donkelaar, Marjolein M J; Van Eijk, Kristel R; Van Erp, Theo G M; Van Rooij, Daan; Walton, Esther; Westlye, Lars T; Whelan, Christopher D; Windham, Beverly G; Winkler, Anderson M; Wittfeld, Katharina; Woldehawariat, Girma; Wolf, Christiane; Wolfers, Thomas; Yanek, Lisa R; Yang, Jingyun; Zijdenbos, Alex; Zwiers, Marcel P; Agartz, Ingrid; Almasy, Laura; Ames, David; Amouyel, Philippe; Andreassen, Ole A; Arepalli, Sampath; Assareh, Amelia A; Barral, Sandra; Bastin, Mark E; Becker, Diane M; Becker, James T; Bennett, David A; Blangero, John; van Bokhoven, Hans; Boomsma, Dorret I; Brodaty, Henry; Brouwer, Rachel M; Brunner, Han G; Buckner, Randy L; Buitelaar, Jan K; Bulayeva, Kazima B; Cahn, Wiepke; Calhoun, Vince D; Cannon, Dara M; Cavalleri, Gianpiero L; Cheng, Ching-Yu; Cichon, Sven; Cookson, Mark R; Corvin, Aiden; Crespo-Facorro, Benedicto; Curran, Joanne E; Czisch, Michael; Dale, Anders M; Davies, Gareth E; De Craen, Anton J M; De Geus, Eco J C; De Jager, Philip L; De Zubicaray, Greig I; Deary, Ian J; Debette, Stéphanie; DeCarli, Charles; Delanty, Norman; Depondt, Chantal; DeStefano, Anita; Dillman, Allissa; Djurovic, Srdjan; Donohoe, Gary; Drevets, Wayne C; Duggirala, Ravi; Dyer, Thomas D; Enzinger, Christian; Erk, Susanne; Espeseth, Thomas; Fedko, Iryna O; Fernández, Guillén; Ferrucci, Luigi; Fisher, Simon E; Fleischman, Debra A; Ford, Ian; Fornage, Myriam; Foroud, Tatiana M; Fox, Peter T; Francks, Clyde; Fukunaga, Masaki; Gibbs, J Raphael; Glahn, David C; Gollub, Randy L; Göring, Harald H H; Green, Robert C; Gruber, Oliver; Gudnason, Vilmundur; Guelfi, Sebastian; Håberg, Asta K; Hansell, Narelle K; Hardy, John; Hartman, Catharina A; Hashimoto, Ryota; Hegenscheid, Katrin; Heinz, Andreas; Le Hellard, Stephanie; Hernandez, Dena G; Heslenfeld, Dirk J; Ho, Beng-Choon; Hoekstra, Pieter J; Hoffmann, Wolfgang; Hofman, Albert; Holsboer, Florian; Homuth, Georg; Hosten, Norbert; Hottenga, Jouke-Jan; Huentelman, Matthew; Hulshoff Pol, Hilleke E; Ikeda, Masashi; Jack, Clifford R; Jenkinson, Mark; Johnson, Robert; Jönsson, Erik G; Jukema, J Wouter; Kahn, René S; Kanai, Ryota; Kloszewska, Iwona; Knopman, David S; Kochunov, Peter; Kwok, John B; Lawrie, Stephen M; Lemaître, Hervé; Liu, Xinmin; Longo, Dan L; Lopez, Oscar L; Lovestone, Simon; Martinez, Oliver; Martinot, Jean-Luc; Mattay, Venkata S; McDonald, Colm; McIntosh, Andrew M; McMahon, Francis J; McMahon, Katie L; Mecocci, Patrizia; Melle, Ingrid; Meyer-Lindenberg, Andreas; Mohnke, Sebastian; Montgomery, Grant W; Morris, Derek W; Mosley, Thomas H; Mühleisen, Thomas W; Müller-Myhsok, Bertram; Nalls, Michael A; Nauck, Matthias; Nichols, Thomas E; Niessen, Wiro J; Nöthen, Markus M; Nyberg, Lars; Ohi, Kazutaka; Olvera, Rene L; Ophoff, Roel A; Pandolfo, Massimo; Paus, Tomas; Pausova, Zdenka; Penninx, Brenda W J H; Pike, G Bruce; Potkin, Steven G; Psaty, Bruce M; Reppermund, Simone; Rietschel, Marcella; Roffman, Joshua L; Romanczuk-Seiferth, Nina; Rotter, Jerome I; Ryten, Mina; Sacco, Ralph L; Sachdev, Perminder S; Saykin, Andrew J; Schmidt, Reinhold; Schmidt, Helena; Schofield, Peter R; Sigursson, Sigurdur; Simmons, Andrew; Singleton, Andrew; Sisodiya, Sanjay M; Smith, Colin; Smoller, Jordan W; Soininen, Hilkka; Steen, Vidar M; Stott, David J; Sussmann, Jessika E; Thalamuthu, Anbupalam; Toga, Arthur W; Traynor, Bryan J; Troncoso, Juan; Tsolaki, Magda; Tzourio, Christophe; Uitterlinden, Andre G; Hernández, Maria C Valdés; Van der Brug, Marcel; van der Lugt, Aad; van der Wee, Nic J A; Van Haren, Neeltje E M; van 't Ent, Dennis; Van Tol, Marie-Jose; Vardarajan, Badri N; Vellas, Bruno; Veltman, Dick J; Völzke, Henry; Walter, Henrik; Wardlaw, Joanna M; Wassink, Thomas H; Weale, Michael E; Weinberger, Daniel R; Weiner, Michael W; Wen, Wei; Westman, Eric; White, Tonya; Wong, Tien Y; Wright, Clinton B; Zielke, Ronald H; Zonderman, Alan B; Martin, Nicholas G; Van Duijn, Cornelia M; Wright, Margaret J; Longstreth, W T; Schumann, Gunter; Grabe, Hans J; Franke, Barbara; Launer, Lenore J; Medland, Sarah E; Seshadri, Sudha; Thompson, Paul M; Ikram, M Arfan

    2017-01-18

    The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (r g =-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness.

  13. Quantitative trait loci and metabolic pathways

    Science.gov (United States)

    McMullen, M. D.; Byrne, P. F.; Snook, M. E.; Wiseman, B. R.; Lee, E. A.; Widstrom, N. W.; Coe, E. H.

    1998-01-01

    The interpretation of quantitative trait locus (QTL) studies is limited by the lack of information on metabolic pathways leading to most economic traits. Inferences about the roles of the underlying genes with a pathway or the nature of their interaction with other loci are generally not possible. An exception is resistance to the corn earworm Helicoverpa zea (Boddie) in maize (Zea mays L.) because of maysin, a C-glycosyl flavone synthesized in silks via a branch of the well characterized flavonoid pathway. Our results using flavone synthesis as a model QTL system indicate: (i) the importance of regulatory loci as QTLs, (ii) the importance of interconnecting biochemical pathways on product levels, (iii) evidence for “channeling” of intermediates, allowing independent synthesis of related compounds, (iv) the utility of QTL analysis in clarifying the role of specific genes in a biochemical pathway, and (v) identification of a previously unknown locus on chromosome 9S affecting flavone level. A greater understanding of the genetic basis of maysin synthesis and associated corn earworm resistance should lead to improved breeding strategies. More broadly, the insights gained in relating a defined genetic and biochemical pathway affecting a quantitative trait should enhance interpretation of the biological basis of variation for other quantitative traits. PMID:9482823

  14. Microsatellite loci isolated from the scleractinian coral, Acropora nobilis.

    Science.gov (United States)

    Isomura, Naoko; Hidaka, Michio

    2008-05-01

    We report the isolation and characterization of eight microsatellite loci from the scleractinian coral, Acropora nobilis. The microsatellite loci were obtained using compound SSR primers or an enrichment protocol. All the loci were polymorphic with four to eight alleles per locus and observed heterozygosities ranging from 0.22 to 0.76. Some of the primers developed for the two congeners, Acropora palmata and Acropora millepora were applicable to A. nobilis. These loci are useful for studying the connectivity among A. nobilis populations in Okinawa, southern Japan. © 2007 The Authors.

  15. The contribution of microbial mats to the arsenic geochemistry of an ancient gold mine

    International Nuclear Information System (INIS)

    Drewniak, Lukasz; Maryan, Natalia; Lewandowski, Wiktor; Kaczanowski, Szymon; Sklodowska, Aleksandra

    2012-01-01

    The ancient Zloty Stok (SW Poland) gold mine is such an environment, where different microbial communities, able to utilize inorganic arsenic species As(III) and As(V), are found. The purpose of the present study was to (i) estimate prokaryotic diversity in the microbial mats in bottom sediments of this gold mine, (ii) identify microorganisms that can metabolize arsenic, and (iii) estimate their potential role in the arsenic geochemistry of the mine and in the environment. The oxidation/reduction experiments showed that the microbial mat community may significantly contribute to arsenic contamination in groundwater. The presence of both arsenite oxidizing and dissimilatory arsenate reducing bacteria in the mat was confirmed by the detection of arsenite oxidase and dissimilatory arsenate reductase genes, respectively. This work also demonstrated that microorganisms utilizing other compounds that naturally co-occur with arsenic are present within the microbial mat community and may contribute to the arsenic geochemistry in the environment. - Highlights: ► The microbial mats from this ancient gold mine are highly diverse community. ► As(III) oxidizing and As(V) reducing bacteria are present in the mats. ► As redox transformations are linked to the metabolism of microbial mats bacteria. ► Microbial mats play a crucial role in the As biogeochemical cycle within the mine. - The microbial mats from this ancient gold mine can mediate oxidation/reduction reaction of arsenic and in this way may significantly contribute to arsenic contamination in groundwater.

  16. Perfect simulation and moment properties for the Matérn type III process

    DEFF Research Database (Denmark)

    Møller, Jesper; Huber, Mark L.; Wolpert, Robert L.

    2010-01-01

    In a seminal work, Bertil Matérn introduced several types of processes for modeling repulsive point processes. In this paper an algorithm is presented for the perfect simulation of the Matérn III process within a bounded window in , fully accounting for edge effects. A simple upper bound on the m......In a seminal work, Bertil Matérn introduced several types of processes for modeling repulsive point processes. In this paper an algorithm is presented for the perfect simulation of the Matérn III process within a bounded window in , fully accounting for edge effects. A simple upper bound...

  17. Reconstruction of hyperspectral image using matting model for classification

    Science.gov (United States)

    Xie, Weiying; Li, Yunsong; Ge, Chiru

    2016-05-01

    Although hyperspectral images (HSIs) captured by satellites provide much information in spectral regions, some bands are redundant or have large amounts of noise, which are not suitable for image analysis. To address this problem, we introduce a method for reconstructing the HSI with noise reduction and contrast enhancement using a matting model for the first time. The matting model refers to each spectral band of an HSI that can be decomposed into three components, i.e., alpha channel, spectral foreground, and spectral background. First, one spectral band of an HSI with more refined information than most other bands is selected, and is referred to as an alpha channel of the HSI to estimate the hyperspectral foreground and hyperspectral background. Finally, a combination operation is applied to reconstruct the HSI. In addition, the support vector machine (SVM) classifier and three sparsity-based classifiers, i.e., orthogonal matching pursuit (OMP), simultaneous OMP, and OMP based on first-order neighborhood system weighted classifiers, are utilized on the reconstructed HSI and the original HSI to verify the effectiveness of the proposed method. Specifically, using the reconstructed HSI, the average accuracy of the SVM classifier can be improved by as much as 19%.

  18. Mechanisms of Mindfulness Training: Monitor and Acceptance Theory (MAT)1

    Science.gov (United States)

    Lindsay, Emily K.; Creswell, J. David

    2016-01-01

    Despite evidence linking trait mindfulness and mindfulness training with a broad range of effects, still little is known about its underlying active mechanisms. Mindfulness is commonly defined as (1) the ongoing monitoring of present-moment experience (2) with an orientation of acceptance. Building on conceptual, clinical, and empirical work, we describe a testable theoretical account to help explain mindfulness effects on cognition, affect, stress, and health outcomes. Specifically, Monitor and Acceptance Theory (MAT) posits that (1), by enhancing awareness of one’s experiences, the skill of attention monitoring explains how mindfulness improves cognitive functioning outcomes, yet this same skill can increase affective reactivity. Second (2), by modifying one’s relation to monitored experience, acceptance is necessary for reducing affective reactivity, such that attention monitoring and acceptance skills together explain how mindfulness improves negative affectivity, stress, and stress-related health outcomes. We discuss how MAT contributes to mindfulness science, suggest plausible alternatives to the account, and offer specific predictions for future research. PMID:27835764

  19. Coastal microbial mat diversity along a natural salinity gradient.

    Directory of Open Access Journals (Sweden)

    Henk Bolhuis

    Full Text Available The North Sea coast of the Dutch barrier island of Schiermonnikoog is covered by microbial mats that initiate a succession of plant communities that eventually results in the development of a densely vegetated salt marsh. The North Sea beach has a natural elevation running from the low water mark to the dunes resulting in gradients of environmental factors perpendicular to the beach. These gradients are due to the input of seawater at the low water mark and of freshwater from upwelling groundwater at the dunes and rainfall. The result is a natural and dynamic salinity gradient depending on the tide, rainfall and wind. We studied the microbial community composition in thirty three samples taken every ten meters along this natural salinity gradient by using denaturing gradient gel electrophoresis (DGGE of rRNA gene fragments. We looked at representatives from each Domain of life (Bacteria, Archaea and Eukarya and with a particular emphasis on Cyanobacteria. Analysis of the DGGE fingerprints together with pigment composition revealed three distinct microbial mat communities, a marine community dominated by diatoms as primary producers, an intermediate brackish community dominated by Cyanobacteria as primary producers and a freshwater community with Cyanobacteria and freshwater green algae.

  20. Lipid Biomarkers for a Hypersaline Microbial Mat Community

    Science.gov (United States)

    Jahnke, Linda L.; Embaye, Tsege; Turk, Kendra A.

    2003-01-01

    The use of lipid biomarkers and their carbon isotopic compositions are valuable tools for establishing links to ancient microbial ecosystems. As witnessed by the stromatolite record, benthic microbial mats grew in shallow water lagoonal environments where microorganisms had virtually no competition apart from the harsh conditions of hypersalinity, desiccation and intense light. Today, the modern counterparts of these microbial ecosystems find appropriate niches in only a few places where extremes eliminate eukaryotic grazers. Answers to many outstanding questions about the evolution of microorganisms and their environments on early Earth are best answered through study of these extant analogs. Lipids associated with various groups of bacteria can be valuable biomarkers for identification of specific groups of microorganisms both in ancient organic-rich sedimentary rocks (geolipids) and contemporary microbial communities (membrane lipids). Use of compound specific isotope analysis adds additional refinement to the identification of biomarker source, so that it is possible to take advantage of the 3C-depletions associated with various functional groups of organisms (i.e. autotrophs, heterotrophs, methanotrophs, methanogens) responsible for the cycling of carbon within a microbial community. Our recent work has focused on a set of hypersaline evaporation ponds at Guerrero Negro, Baja California Sur, Mexico which support the abundant growth of Microcoleus-dominated microbial mats. Specific biomarkers for diatoms, cyanobacteria, archaea, green nonsulfur (GNS), sulfate reducing, and methanotrophic bacteria have been identified. Analyses of the ester-bound fatty acids indicate a highly diverse microbial community, dominated by photosynthetic organisms at the surface.

  1. Zirconium Hydroxide-coated Nanofiber Mats for Nerve Agent Decontamination.

    Science.gov (United States)

    Kim, Sohee; Ying, Wu Bin; Jung, Hyunsook; Ryu, Sam Gon; Lee, Bumjae; Lee, Kyung Jin

    2017-03-16

    Diverse innovative fabrics with specific functionalities have been developed for requirements such as self-decontamination of chemical/biological pollutants and toxic nerve agents. In this work, Zr(OH) 4 -coated nylon-6,6 nanofiber mats were fabricated for the decontamination of nerve agents. Nylon-6,6 fabric was prepared via the electrospinning process, followed by coating with Zr(OH) 4 , which was obtained by the hydrolysis of Zr(OBu) 4 by a sol-gel reaction on nanofiber surfaces. The reaction conditions were optimized by varying the amounts of Zr(OBu) 4 ,the reaction time, and the temperature of the sol-gel reaction. The composite nanofibers show high decontamination efficiency against diisopropylfluorophosphate, which is a nerve agent analogue, due to its high nucleophilicity that aids in the catalysis of the hydrolysis of the phosphonate ester bonds. Composite nanofiber mats have a large potential and can be applied in specific fields such as military and medical markets. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Taxonomy, sexuality and mating types of Diaporthe adunca

    NARCIS (Netherlands)

    Linders, E.G.A.; Van der Aa, H.A.

    1995-01-01

    The perithecial stage of the pathogenic fungus Diaporthe adunca, found for the first time since 1851 in natural populations of its host Plantago lanceolata, is described. Analysis of artificial reciprocal crosses and progeny from naturally occurring perithecia indicated that D. adunca is

  3. lociNGS: a lightweight alternative for assessing suitability of next-generation loci for evolutionary analysis.

    Directory of Open Access Journals (Sweden)

    Sarah M Hird

    Full Text Available Genomic enrichment methods and next-generation sequencing produce uneven coverage for the portions of the genome (the loci they target; this information is essential for ascertaining the suitability of each locus for further analysis. lociNGS is a user-friendly accessory program that takes multi-FASTA formatted loci, next-generation sequence alignments and demographic data as input and collates, displays and outputs information about the data. Summary information includes the parameters coverage per locus, coverage per individual and number of polymorphic sites, among others. The program can output the raw sequences used to call loci from next-generation sequencing data. lociNGS also reformats subsets of loci in three commonly used formats for multi-locus phylogeographic and population genetics analyses - NEXUS, IMa2 and Migrate. lociNGS is available at https://github.com/SHird/lociNGS and is dependent on installation of MongoDB (freely available at http://www.mongodb.org/downloads. lociNGS is written in Python and is supported on MacOSX and Unix; it is distributed under a GNU General Public License.

  4. Nonparametric functional mapping of quantitative trait loci.

    Science.gov (United States)

    Yang, Jie; Wu, Rongling; Casella, George

    2009-03-01

    Functional mapping is a useful tool for mapping quantitative trait loci (QTL) that control dynamic traits. It incorporates mathematical aspects of biological processes into the mixture model-based likelihood setting for QTL mapping, thus increasing the power of QTL detection and the precision of parameter estimation. However, in many situations there is no obvious functional form and, in such cases, this strategy will not be optimal. Here we propose to use nonparametric function estimation, typically implemented with B-splines, to estimate the underlying functional form of phenotypic trajectories, and then construct a nonparametric test to find evidence of existing QTL. Using the representation of a nonparametric regression as a mixed model, the final test statistic is a likelihood ratio test. We consider two types of genetic maps: dense maps and general maps, and the power of nonparametric functional mapping is investigated through simulation studies and demonstrated by examples.

  5. Ecological and genetic interactions between cyanobacteria and viruses in a low-oxygen mat community inferred through metagenomics and metatranscriptomics.

    Science.gov (United States)

    Voorhies, Alexander A; Eisenlord, Sarah D; Marcus, Daniel N; Duhaime, Melissa B; Biddanda, Bopaiah A; Cavalcoli, James D; Dick, Gregory J

    2016-02-01

    Metagenomic and metatranscriptomic sequencing was conducted on cyanobacterial mats of the Middle Island Sinkhole (MIS), Lake Huron. Metagenomic data from 14 samples collected over 5 years were used to reconstruct genomes of two genotypes of a novel virus, designated PhV1 type A and PhV1 type B. Both viral genotypes encode and express nblA, a gene involved in degrading phycobilisomes, which are complexes of pigmented proteins that harvest light for photosynthesis. Phylogenetic analysis indicated that the viral-encoded nblA is derived from the host cyanobacterium, Phormidium MIS-PhA. The cyanobacterial host also has two complete CRISPR (clustered regularly interspaced short palindromic repeats) systems that serve as defence mechanisms for bacteria and archaea against viruses and plasmids. One 45 bp CRISPR spacer from Phormidium had 100% nucleotide identity to PhV1 type B, but this region was absent from PhV1 type A. Transcripts from PhV1 and the Phormidium CRISPR loci were detected in all six metatranscriptomic data sets (three during the day and three at night), indicating that both are transcriptionally active in the environment. These results reveal ecological and genetic interactions between viruses and cyanobacteria at MIS, highlighting the value of parallel analysis of viruses and hosts in understanding ecological interactions in natural communities. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  6. Microbial mat structures in profile: The Neoproterozoic Sonia Sandstone, Rajasthan, India

    Science.gov (United States)

    Samanta, Pradip; Mukhopadhyay, Soumik; Mondal, Anudeb; Sarkar, Subir

    2011-01-01

    Ubiquitous microorganisms, especially cyanobacteria preferably grow on the sediment surface thereby producing microbial mats. In the absence of grazers and bioturbators, microbial mat is a unique feature of the Proterozoic. Most of the papers so far published described a wide variety of bed surface microbial mat structures with rare illustrations from sections perpendicular to bedding. Nonetheless, bed surface exposures are relatively rare in rock records. This limitation of bed surface exposures in rock records suggest that a study of microbial mats in bed-across sections is needed. The 60 m thick coastal marine interval of the Sonia Sandstone Formation is bounded between two terrestrial intervals, a transgressive lag at the base and an unconformity at the top, and has been chosen for exploration of microbial mat structures in bed-across sections. A wide variety of microbial mat-induced structures in bed-across sections are preserved within the coastal interval of the Sonia Sandstone. Though many of these structures are similar in some aspects with bed surface structures, some of those presented here are new. The palaeogeographic range of these microbial structures extends from supralittoral to neritic. Diagenetic alterations of microbial mats produce pyrite and those zones are suitable for the preservation of microbial remains. SEM and EDAX analyses show fossil preservation of filamentous microbial remains that confirm the presence of microbial mats within the coastal interval of the Sonia Sandstone. Effects of proliferation of microbial mats in the siliciclastic depositional setting are numerous. The mat-cover on sediment surfaces hinders reworking and/or erosion of the sediments thereby increases the net sedimentation rate. Successive deposition and preservation of thick microbial mat layer under reducing environments should have a great potential for hydrocarbon production and preservation and therefore these Proterozoic formations could be a target for

  7. Evaluation of polyacrylonitrile electrospun nano-fibrous mats as leukocyte removal filter media.

    Science.gov (United States)

    Pourbaghi, Raha; Zarrebini, Mohammad; Semnani, Dariush; Pourazar, Abbasali; Akbari, Nahid; Shamsfar, Reihaneh

    2017-09-13

    Removal of leukocytes from blood products is the most effective means for elimination of undesirable side effects and prevention of possible reactions in recipients. Micro-fibrous mats are currently used for removal of leukocytes from blood. In this study, samples of electrospun nano-fibrous mats were produced. The performance of the produced electrospun nano-fibrous mats as means of leukocytes removal from fresh whole blood was both evaluated and compared with that of commercially available micro-fibrous mats. In order to produce the samples, polyacrylonitrile (PAN) nano-fibrous mats were made under different electrospinning conditions. Mean fiber diameter, pore characterization and surface roughness of the PAN nano-fibrous mats were determined using image processing technique. In order to evaluate the surface tension of the fabricated mats, water contact angle was measured. The leukocyte removal performance, erythrocytes recovery percent and hemolysis rate of the nano-fibrous mats were compared. The effectiveness of nano-fibrous mats in removing leukocyte was established using both scanning electron microscope and optical microscope. Results showed that for given weight, the fabricated nano-fibrous mats were not only more efficient but also more cost-effective than their commercial counterparts. Results confirmed that changes in mean fiber diameter, the number of layer and weight of each layer in the absence of any chemical reaction or physical surface modification, the fabricated nano-fibrous mats were able to remove 5-log of leukocytes. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2017. © 2017 Wiley Periodicals, Inc.

  8. Discovery and refinement of loci associated with lipid levels

    NARCIS (Netherlands)

    Willer, Cristen J.; Schmidt, Ellen M.; Sengupta, Sebanti; Peloso, Gina M.; Gustafsson, Stefan; Kanoni, Stavroula; Ganna, Andrea; Chen, Jin; Buchkovich, Martin L.; Mora, Samia; Beckmann, Jacques S.; Bragg-Gresham, Jennifer L.; Chang, Hsing-Yi; Demirkan, Ayşe; den Hertog, Heleen M.; Do, Ron; Donnelly, Louise A.; Ehret, Georg B.; Esko, Tõnu; Feitosa, Mary F.; Ferreira, Teresa; Fischer, Krista; Fontanillas, Pierre; Fraser, Ross M.; Freitag, Daniel F.; Gurdasani, Deepti; Heikkilä, Kauko; Hyppönen, Elina; Isaacs, Aaron; Jackson, Anne U.; Johansson, Asa; Johnson, Toby; Kaakinen, Marika; Kettunen, Johannes; Kleber, Marcus E.; Li, Xiaohui; Luan, Jian'an; Lyytikäinen, Leo-Pekka; Magnusson, Patrik K. E.; Mangino, Massimo; Mihailov, Evelin; Montasser, May E.; Müller-Nurasyid, Martina; Nolte, Ilja M.; O'Connell, Jeffrey R.; Palmer, Cameron D.; Perola, Markus; Petersen, Ann-Kristin; Sanna, Serena; Saxena, Richa; Service, Susan K.; Shah, Sonia; Shungin, Dmitry; Sidore, Carlo; Song, Ci; Strawbridge, Rona J.; Surakka, Ida; Tanaka, Toshiko; Teslovich, Tanya M.; Thorleifsson, Gudmar; van den Herik, Evita G.; Voight, Benjamin F.; Volcik, Kelly A.; Waite, Lindsay L.; Wong, Andrew; Wu, Ying; Zhang, Weihua; Absher, Devin; Asiki, Gershim; Barroso, Inês; Been, Latonya F.; Bolton, Jennifer L.; Bonnycastle, Lori L.; Brambilla, Paolo; Burnett, Mary S.; Cesana, Giancarlo; Dimitriou, Maria; Doney, Alex S. F.; Döring, Angela; Elliott, Paul; Epstein, Stephen E.; Eyjolfsson, Gudmundur Ingi; Gigante, Bruna; Goodarzi, Mark O.; Grallert, Harald; Gravito, Martha L.; Groves, Christopher J.; Hallmans, Göran; Hartikainen, Anna-Liisa; Hayward, Caroline; Hernandez, Dena; Hicks, Andrew A.; Holm, Hilma; Hung, Yi-Jen; Illig, Thomas; Jones, Michelle R.; Kaleebu, Pontiano; Kastelein, John J. P.; Khaw, Kay-Tee; Kim, Eric; Klopp, Norman; Komulainen, Pirjo; Kumari, Meena; Langenberg, Claudia; Lehtimäki, Terho; Lin, Shih-Yi; Lindström, Jaana; Loos, Ruth J. F.; Mach, François; McArdle, Wendy L.; Meisinger, Christa; Mitchell, Braxton D.; Müller, Gabrielle; Nagaraja, Ramaiah; Narisu, Narisu; Nieminen, Tuomo V. M.; Nsubuga, Rebecca N.; Olafsson, Isleifur; Ong, Ken K.; Palotie, Aarno; Papamarkou, Theodore; Pomilla, Cristina; Pouta, Anneli; Rader, Daniel J.; Reilly, Muredach P.; Ridker, Paul M.; Rivadeneira, Fernando; Rudan, Igor; Ruokonen, Aimo; Samani, Nilesh; Scharnagl, Hubert; Seeley, Janet; Silander, Kaisa; Stancáková, Alena; Stirrups, Kathleen; Swift, Amy J.; Tiret, Laurence; Uitterlinden, Andre G.; van Pelt, L. Joost; Vedantam, Sailaja; Wainwright, Nicholas; Wijmenga, Cisca; Wild, Sarah H.; Willemsen, Gonneke; Wilsgaard, Tom; Wilson, James F.; Young, Elizabeth H.; Zhao, Jing Hua; Adair, Linda S.; Arveiler, Dominique; Assimes, Themistocles L.; Bandinelli, Stefania; Bennett, Franklyn; Bochud, Murielle; Boehm, Bernhard O.; Boomsma, Dorret I.; Borecki, Ingrid B.; Bornstein, Stefan R.; Bovet, Pascal; Burnier, Michel; Campbell, Harry; Chakravarti, Aravinda; Chambers, John C.; Chen, Yii-Der Ida; Collins, Francis S.; Cooper, Richard S.; Danesh, John; Dedoussis, George; de Faire, Ulf; Feranil, Alan B.; Ferrières, Jean; Ferrucci, Luigi; Freimer, Nelson B.; Gieger, Christian; Groop, Leif C.; Gudnason, Vilmundur; Gyllensten, Ulf; Hamsten, Anders; Harris, Tamara B.; Hingorani, Aroon; Hirschhorn, Joel N.; Hofman, Albert; Hovingh, G. Kees; Hsiung, Chao Agnes; Humphries, Steve E.; Hunt, Steven C.; Hveem, Kristian; Iribarren, Carlos; Järvelin, Marjo-Riitta; Jula, Antti; Kähönen, Mika; Kaprio, Jaakko; Kesäniemi, Antero; Kivimaki, Mika; Kooner, Jaspal S.; Koudstaal, Peter J.; Krauss, Ronald M.; Kuh, Diana; Kuusisto, Johanna; Kyvik, Kirsten O.; Laakso, Markku; Lakka, Timo A.; Lind, Lars; Lindgren, Cecilia M.; Martin, Nicholas G.; März, Winfried; McCarthy, Mark I.; McKenzie, Colin A.; Meneton, Pierre; Metspalu, Andres; Moilanen, Leena; Morris, Andrew D.; Munroe, Patricia B.; Njølstad, Inger; Pedersen, Nancy L.; Power, Chris; Pramstaller, Peter P.; Price, Jackie F.; Psaty, Bruce M.; Quertermous, Thomas; Rauramaa, Rainer; Saleheen, Danish; Salomaa, Veikko; Sanghera, Dharambir K.; Saramies, Jouko; Schwarz, Peter E. H.; Sheu, Wayne H.-H.; Shuldiner, Alan R.; Siegbahn, Agneta; Spector, Tim D.; Stefansson, Kari; Strachan, David P.; Tayo, Bamidele O.; Tremoli, Elena; Tuomilehto, Jaakko; Uusitupa, Matti; van Duijn, Cornelia M.; Vollenweider, Peter; Wallentin, Lars; Wareham, Nicholas J.; Whitfield, John B.; Wolffenbuttel, Bruce H. R.; Ordovas, Jose M.; Boerwinkle, Eric; Palmer, Colin N. A.; Thorsteinsdottir, Unnur; Chasman, Daniel I.; Rotter, Jerome I.; Franks, Paul W.; Ripatti, Samuli; Cupples, L. Adrienne; Sandhu, Manjinder S.; Rich, Stephen S.; Boehnke, Michael; Deloukas, Panos; Kathiresan, Sekar; Mohlke, Karen L.; Ingelsson, Erik; Abecasis, Gonçalo R.

    2013-01-01

    Levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides and total cholesterol are heritable, modifiable risk factors for coronary artery disease. To identify new loci and refine known loci influencing these lipids, we examined 188,577

  9. Unraveling possible association between quantitative trait loci (QTL ...

    African Journals Online (AJOL)

    Unraveling possible association between quantitative trait loci (QTL) for partial resistance and nonhost resistance in food barley ( Hordeum vulgaris L.) ... Abstract. Many quantitative trait loci (QTLs) in different barley populations were discovered for resistance to Puccinia hordei and heterologous rust species. Partial ...

  10. Discovery and refinement of loci associated with lipid levels

    DEFF Research Database (Denmark)

    Willer, C. J.; Schmidt, E. M.; Sengupta, S.

    2013-01-01

    Levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides and total cholesterol are heritable, modifiable risk factors for coronary artery disease. To identify new loci and refine known loci influencing these lipids, we examined 188,577 individ...... of using genetic data from individuals of diverse ancestry and provide insights into the biological mechanisms regulating blood lipids to guide future genetic, biological and therapeutic research.......Levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides and total cholesterol are heritable, modifiable risk factors for coronary artery disease. To identify new loci and refine known loci influencing these lipids, we examined 188......,577 individuals using genome-wide and custom genotyping arrays. We identify and annotate 157 loci associated with lipid levels at P lipid levels in humans. Using dense genotyping in individuals of European, East Asian, South Asian and African ancestry...

  11. Species-Level Phylogeny and Polyploid Relationships in Hordeum (Poaceae) Inferred by Next-Generation Sequencing and In Silico Cloning of Multiple Nuclear Loci.

    Science.gov (United States)

    Brassac, Jonathan; Blattner, Frank R

    2015-09-01

    Polyploidization is an important speciation mechanism in the barley genus Hordeum. To analyze evolutionary changes after allopolyploidization, knowledge of parental relationships is essential. One chloroplast and 12 nuclear single-copy loci were amplified by polymerase chain reaction (PCR) in all Hordeum plus six out-group species. Amplicons from each of 96 individuals were pooled, sheared, labeled with individual-specific barcodes and sequenced in a single run on a 454 platform. Reference sequences were obtained by cloning and Sanger sequencing of all loci for nine supplementary individuals. The 454 reads were assembled into contigs representing the 13 loci and, for polyploids, also homoeologues. Phylogenetic analyses were conducted for all loci separately and for a concatenated data matrix of all loci. For diploid taxa, a Bayesian concordance analysis and a coalescent-based dated species tree was inferred from all gene trees. Chloroplast matK was used to determine the maternal parent in allopolyploid taxa. The relative performance of different multilocus analyses in the presence of incomplete lineage sorting and hybridization was also assessed. The resulting multilocus phylogeny reveals for the first time species phylogeny and progenitor-derivative relationships of all di- and polyploid Hordeum taxa within a single analysis. Our study proves that it is possible to obtain a multilocus species-level phylogeny for di- and polyploid taxa by combining PCR with next-generation sequencing, without cloning and without creating a heavy load of sequence data. © The Author(s) 2015. Published by Oxford University Press, on behalf of the Society of Systematic Biologists.

  12. Testing the utility of matK and ITS DNA regions for discrimination of Allium species

    Science.gov (United States)

    Molecular phylogenetic analysis of the genus Allium L. has been mainly based on the nucleotide sequences of ITS region. In 2009 matK and rbcL were accepted as a two-locus DNA barcode to classify plant species by the Consortium for the Barcode of Life (CBOL) Plant Working Group. MatK region has been ...

  13. Coastal microbial mats: the physiology of a small-scale ecosystem

    NARCIS (Netherlands)

    Stal, L.J.

    2001-01-01

    Coastal inter-tidal sandy sediments, salt marshes and mangrove forests often support the development of microbial mats. Microbial mats are complex associations of one or several functional groups of microorganisms and their formation usually starts with the growth of a cyanobacterial population on a

  14. COMPETITION BETWEEN ANOXYGENIC PHOTOTROPHIC BACTERIA AND COLORLESS SULFUR BACTERIA IN A MICROBIAL MAT

    NARCIS (Netherlands)

    VISSCHER, PT; VANDENENDE, FP; SCHAUB, BEM; VANGEMERDEN, H

    The populations of chemolithoautotrophic (colorless) sulfur bacteria and anoxygenic phototrophic bacteria were enumerated in a marine microbial mat. The highest population densities were found in the 0-5 mm layer of the mat: 2.0 X 10(9) cells CM-3 sediment, and 4.0 X 10(7) cells cm-3 sediment for

  15. Polycaprolactone-Chitin Nanofibrous Mats as Potential Scaffolds for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Min Sup Kim

    2012-01-01

    Full Text Available We describe here the preparation of poly(caprolactone (PCL-chitin nanofibrous mats by electrospinning from a blended solution of PCL and chitin dissolved in a cosolvent, 1,1,1,3,3,3-hexafluoro-2-propanol and trifluoroacetic acid. Scanning electron microscopy showed that the neutralized PCL-chitin nanofibrous mats were morphologically stable, with a mean diameter of 340.5±2.6 nm, compared with a diameter of 524.2±12.1 nm for PCL mats. The nanofibrous mats showed decreased water contact angles as the proportion of chitin increased. However, the tensile properties of nanofibrous mats containing 30~50% (wt/wt chitin were enhanced compared with PCL-only mats. In vitro studies showed that the viability of human dermal fibroblasts (HDFs for up to 7 days in culture was higher on composite (OD value: 1.42±0.09 than on PCL-only (0.51±0.14 nanofibrous mats, with viability correlated with chitin concentration. Together, our results suggest that PCL-chitin nanofibrous mats can be used as an implantable substrate to modulate HDF viability in tissue engineering.

  16. Design of a smart textile mat to study pressure distribution on multiple foam material configurations

    NARCIS (Netherlands)

    Donselaar, van R.; Chen, W.

    2011-01-01

    In this paper, we present a design of a smart textile pressure mat to study the pressure distribution with multiple foam material configurations for neonatal monitoring at Neonatal Intensive Care Units (NICU). A smart textile mat with 64 pressure sensors has been developed including software at the

  17. Evaluating carbon stores at the earth-atmosphere interface: moss and lichen mats of subarctic Alaska

    Science.gov (United States)

    Robert J. Smith; Sarah Jovan; Bruce. McCune

    2015-01-01

    A fundamental goal of the forest inventory in interior Alaska is to accurately estimate carbon pools in a way that sheds light on the feedbacks between forests and climate. In boreal forests, moss and lichen mats often serve as the interface between soils and the atmosphere, therefore characterizing the biomass and composition of mats is essential for understanding how...

  18. Electrospun chitosan-based nanocomposite mats reinforced with chitin nanocrystals for wound dressing

    CSIR Research Space (South Africa)

    Naseria, N

    2014-08-01

    Full Text Available The aim of this study was to develop electrospun chitosan/polyethylene oxide-based randomly oriented fiber mats reinforced with chitin nanocrystals (ChNC) for wound dressing. Microscopy studies showedporous mats of smooth and beadless fibers...

  19. Distinctive fungal and bacterial communities are associated with mats formed by ectomycorrhizal fungi

    Science.gov (United States)

    Laurel A. Kluber; Jane E. Smith; David D. Myrold

    2011-01-01

    The distinct rhizomorphic mats formed by ectomycorrhizal Piloderma fungi are common features of the organic soil horizons of coniferous forests of the Pacific Northwest. These mats have been found to cover 25-40% of the forest floor in some Douglas-fir stands, and are associated with physical and biochemical properties that distinguish them from...

  20. Estimation of axial stiffness of plant fibres from compaction of non-woven mats

    DEFF Research Database (Denmark)

    Gamstedt, E. K.; Bommier, E.; Madsen, Bo

    2014-01-01

    -plane randomly oriented fibre mats. The model by Toll is used to relate the load-displacement curve from the test to the Young modulus of the fibre, taking into account the natural variability in fibre cross section. Several tests have been performed on hemp fibre mats and compared with results from single...

  1. Methylmercury enters an aquatic food web through acidophilic microbial mats in Yellowstone National Park, Wyoming.

    Science.gov (United States)

    Boyd, Eric S; King, Susan; Tomberlin, Jeffery K; Nordstrom, D Kirk; Krabbenhoft, David P; Barkay, Tamar; Geesey, Gill G

    2009-04-01

    Microbial mats are a visible and abundant life form inhabiting the extreme environments in Yellowstone National Park (YNP), WY, USA. Little is known of their role in food webs that exist in the Park's geothermal habitats. Eukaryotic green algae associated with a phototrophic green/purple Zygogonium microbial mat community that inhabits low-temperature regions of acidic (pH approximately 3.0) thermal springs were found to serve as a food source for stratiomyid (Diptera: Stratiomyidae) larvae. Mercury in spring source water was taken up and concentrated by the mat biomass. Monomethylmercury compounds (MeHg(+)), while undetectable or near the detection limit (0.025 ng l(-1)) in the source water of the springs, was present at concentrations of 4-7 ng g(-1) dry weight of mat biomass. Detection of MeHg(+) in tracheal tissue of larvae grazing the mat suggests that MeHg(+) enters this geothermal food web through the phototrophic microbial mat community. The concentration of MeHg(+) was two to five times higher in larval tissue than mat biomass indicating MeHg(+) biomagnification occurred between primary producer and primary consumer trophic levels. The Zygogonium mat community and stratiomyid larvae may also play a role in the transfer of MeHg(+) to species in the food web whose range extends beyond a particular geothermal feature of YNP.

  2. Perfect simulation and moment properties for the Matérn type III process

    DEFF Research Database (Denmark)

    Møller, Jesper; Huber, Mark L.; Wolpert, Robert L.

    In a seminal work, Bertil Matérn introduced several types of processes for modeling repulsive point processes. In this paper an algorithm is presented for the perfect simulation of the Mat´ern III process within a bounded window in Rd fully accounting for edge effects. A simple upper bound...

  3. Polyelectrolyte-Functionalized Nanofiber Mats Control the Collection and Inactivation of Escherichia coli

    Directory of Open Access Journals (Sweden)

    Katrina A. Rieger

    2016-04-01

    Full Text Available Quantifying the effect that nanofiber mat chemistry and hydrophilicity have on microorganism collection and inactivation is critical in biomedical applications. In this study, the collection and inactivation of Escherichia coli K12 was examined using cellulose nanofiber mats that were surface-functionalized using three polyelectrolytes: poly (acrylic acid (PAA, chitosan (CS, and polydiallyldimethylammonium chloride (pDADMAC. The polyelectrolyte functionalized nanofiber mats retained the cylindrical morphology and average fiber diameter (~0.84 µm of the underlying cellulose nanofibers. X-ray photoelectron spectroscopy (XPS and contact angle measurements confirmed the presence of polycations or polyanions on the surface of the nanofiber mats. Both the control cellulose and pDADMAC-functionalized nanofiber mats exhibited a high collection of E. coli K12, which suggests that mat hydrophilicity may play a larger role than surface charge on cell collection. While the minimum concentration of polycations needed to inhibit E. coli K12 was 800 µg/mL for both CS and pDADMAC, once immobilized, pDADMAC-functionalized nanofiber mats exhibited a higher inactivation of E. coli K12, (~97%. Here, we demonstrate that the collection and inactivation of microorganisms by electrospun cellulose nanofiber mats can be tailored through a facile polyelectrolyte functionalization process.

  4. Polyelectrolyte-Functionalized Nanofiber Mats Control the Collection and Inactivation of Escherichia coli

    Science.gov (United States)

    Rieger, Katrina A.; Porter, Michael; Schiffman, Jessica D.

    2016-01-01

    Quantifying the effect that nanofiber mat chemistry and hydrophilicity have on microorganism collection and inactivation is critical in biomedical applications. In this study, the collection and inactivation of Escherichia coli K12 was examined using cellulose nanofiber mats that were surface-functionalized using three polyelectrolytes: poly (acrylic acid) (PAA), chitosan (CS), and polydiallyldimethylammonium chloride (pDADMAC). The polyelectrolyte functionalized nanofiber mats retained the cylindrical morphology and average fiber diameter (~0.84 µm) of the underlying cellulose nanofibers. X-ray photoelectron spectroscopy (XPS) and contact angle measurements confirmed the presence of polycations or polyanions on the surface of the nanofiber mats. Both the control cellulose and pDADMAC-functionalized nanofiber mats exhibited a high collection of E. coli K12, which suggests that mat hydrophilicity may play a larger role than surface charge on cell collection. While the minimum concentration of polycations needed to inhibit E. coli K12 was 800 µg/mL for both CS and pDADMAC, once immobilized, pDADMAC-functionalized nanofiber mats exhibited a higher inactivation of E. coli K12, (~97%). Here, we demonstrate that the collection and inactivation of microorganisms by electrospun cellulose nanofiber mats can be tailored through a facile polyelectrolyte functionalization process. PMID:28773422

  5. Electrospun polyvinylpyrrolidone (PVP)/green tea extract composite nanofiber mats and their antioxidant activities

    Science.gov (United States)

    Pusporini, Pusporini; Edikresnha, Dhewa; Sriyanti, Ida; Suciati, Tri; Miftahul Munir, Muhammad; Khairurrijal, Khairurrijal

    2018-05-01

    Electrospinning was employed to make PVP (polyvinylpyrrolidone)/GTE (green tea extract) composite nanofiber mats. The electrospun PVP nanofiber mat as well as the PVP/GTE nanofiber mats were uniform. The average fiber diameter of PVP/GTE composite nanofiber mat decreased with increasing the GTE weight fraction (or decreasing the PVP weight fraction) in the PVP/GTE solution because the PVP/GTE solution concentration decreased. Then, the broad FTIR peak representing the stretching vibrations of O–H in hydroxyl groups of phenols and the stretching of N–H in amine groups of the GTE paste shifted to higher wavenumbers in the PVP/GTE composite nanofiber mats. These peak shifts implied that PVP and catechins of GTE in the PVP/GTE composite nanofiber mats had intermolecular interactions via hydrogen bonds between carbonyl groups of PVP and hydroxyl groups of catechins in GTE. Lastly, the antioxidant activity of the PVP/GTE composite nanofiber mat increased with reducing the average fiber diameter because the amount of catechins in the composite nanofiber mat increased with the increase of surface area due to the reduction of the average fiber diameter.

  6. Biomedical Applications of Antibacterial Nanofiber Mats Made of Electrospinning with Wire Electrodes

    Directory of Open Access Journals (Sweden)

    Yi-Jun Pan

    2016-02-01

    Full Text Available Twisted stainless steel wires are used as wire electrodes for electrospinning the polyvinyl alcohol (PVA/zinc citrate nanofiber mats. The morphology and diameter of the nanofibers in PVA/zinc citrate nanofiber mats are evaluated. We measured the antibacterial efficacy against Staphylococcus aureus (S. aureus and Escherichia coli (E. coli of the nanofiber mats. We also examined the cell adhesion affinity of mammalian tissue culture cells on these nanofiber mats. Our results indicate that an increase in zinc citrate increases the viscosity and electrical conductivity of PVA solution. In addition, increasing zinc citrate results in a smaller diameter of nanofibers that reaches below 100 nm. According to the antibacterial test results, increasing zinc citrate enlarges the inhibition zone of S. aureus but only has a bacteriostatic effect against E. coli. Finally, cell adhesion test results indicate that all nanofiber mats have satisfactory cell attachment regardless of the content of zinc citrate.

  7. MatLab Programming for Engineers Having No Formal Programming Knowledge

    Science.gov (United States)

    Shaykhian, Linda H.; Shaykhian, Gholam Ali

    2007-01-01

    MatLab is one of the most widely used very high level programming languages for Scientific and engineering computations. It is very user-friendly and needs practically no formal programming knowledge. Presented here are MatLab programming aspects and not just the MatLab commands for scientists and engineers who do not have formal programming training and also have no significant time to spare for learning programming to solve their real world problems. Specifically provided are programs for visualization. Also, stated are the current limitations of the MatLab, which possibly can be taken care of by Mathworks Inc. in a future version to make MatLab more versatile.

  8. Convergent evolution of chromosomal sex-determining regions in the animal and fungal kingdoms.

    Directory of Open Access Journals (Sweden)

    James A Fraser

    2004-12-01

    Full Text Available Sexual identity is governed by sex chromosomes in plants and animals, and by mating type (MAT loci in fungi. Comparative analysis of the MAT locus from a species cluster of the human fungal pathogen Cryptococcus revealed sequential evolutionary events that fashioned this large, highly unusual region. We hypothesize that MAT evolved via four main steps, beginning with acquisition of genes into two unlinked sex-determining regions, forming independent gene clusters that then fused via chromosomal translocation. A transitional tripolar intermediate state then converted to a bipolar system via gene conversion or recombination between the linked and unlinked sex-determining regions. MAT was subsequently subjected to intra- and interallelic gene conversion and inversions that suppress recombination. These events resemble those that shaped mammalian sex chromosomes, illustrating convergent evolution in sex-determining structures in the animal and fungal kingdoms.

  9. Validity Study of a Jump Mat Compared to the Reference Standard Force Plate.

    Science.gov (United States)

    Rogan, Slavko; Radlinger, Lorenz; Imhasly, Caroline; Kneubuehler, Andrea; Hilfiker, Roger

    2015-12-01

    In the field of vertical jump diagnostics, force plates (FP) are the reference standard. Recently, despite a lack of evidence, jump mats have been used increasingly. Important factors in favor of jumping mats are their low cost and portability. This validity study compared the Haynl-Elektronik jump mat (HE jump mat) with the reference standard force plate. Ten healthy volunteers participated and each participant completed three series of five drop jumps (DJ). The parameters ground contact time (GCT) and vertical jump height (VJH) from the HE jump mat and the FP were used to evaluate the concurrent validity. The following statistical calculations were performed: Pearson's correlation (r), Bland-Altman plots (standard and for adjusted trend), and regression equations. The Bland-Altman plots suggest that the HE jump mat measures shorter contact times and higher jump heights than the FP. The trend-adjusted Bland-Altman plot shows higher mean differences and wider wing-spreads of confidence limits during longer GCT. During the VJH the mean differences and the wing-spreads of the confidence limits throughout the range present as relatively constant. The following regression equations were created, as close as possible to the true value: GCT = 5.920385 + 1.072293 × [value HE jump mat] and VJH = -1.73777 + 1.011156 × [value HE jump mat]. The HE jump mat can be recommended in relation to the validity of constraints. In this study, only a part of the quality criteria were examined. For the final recommendation it is advised to examine the HE jump mat on the other quality criteria (test-retest reliability, sensitivity change).

  10. Association mapping of partitioning loci in barley

    Directory of Open Access Journals (Sweden)

    Mackay Ian J

    2008-02-01

    Full Text Available Abstract Background Association mapping, initially developed in human disease genetics, is now being applied to plant species. The model species Arabidopsis provided some of the first examples of association mapping in plants, identifying previously cloned flowering time genes, despite high population sub-structure. More recently, association genetics has been applied to barley, where breeding activity has resulted in a high degree of population sub-structure. A major genotypic division within barley is that between winter- and spring-sown varieties, which differ in their requirement for vernalization to promote subsequent flowering. To date, all attempts to validate association genetics in barley by identifying major flowering time loci that control vernalization requirement (VRN-H1 and VRN-H2 have failed. Here, we validate the use of association genetics in barley by identifying VRN-H1 and VRN-H2, despite their prominent role in determining population sub-structure. Results By taking barley as a typical inbreeding crop, and seasonal growth habit as a major partitioning phenotype, we develop an association mapping approach which successfully identifies VRN-H1 and VRN-H2, the underlying loci largely responsible for this agronomic division. We find a combination of Structured Association followed by Genomic Control to correct for population structure and inflation of the test statistic, resolved significant associations only with VRN-H1 and the VRN-H2 candidate genes, as well as two genes closely linked to VRN-H1 (HvCSFs1 and HvPHYC. Conclusion We show that, after employing appropriate statistical methods to correct for population sub-structure, the genome-wide partitioning effect of allelic status at VRN-H1 and VRN-H2 does not result in the high levels of spurious association expected to occur in highly structured samples. Furthermore, we demonstrate that both VRN-H1 and the candidate VRN-H2 genes can be identified using association mapping

  11. Asexual propagation of a virulent clone complex in a human and feline outbreak of sporotrichosis.

    Science.gov (United States)

    Teixeira, Marcus de Melo; Rodrigues, Anderson Messias; Tsui, Clement K M; de Almeida, Luiz Gonzaga Paulo; Van Diepeningen, Anne D; van den Ende, Bert Gerrits; Fernandes, Geisa Ferreira; Kano, Rui; Hamelin, Richard C; Lopes-Bezerra, Leila Maria; Vasconcelos, Ana Tereza Ribeiro; de Hoog, Sybren; de Camargo, Zoilo Pires; Felipe, Maria Sueli Soares

    2015-02-01

    Sporotrichosis is one of the most frequent subcutaneous fungal infections in humans and animals caused by members of the plant-associated, dimorphic genus Sporothrix. Three of the four medically important Sporothrix species found in Brazil have been considered asexual as no sexual stage has ever been reported in Sporothrix schenckii, Sporothrix brasiliensis, or Sporothrix globosa. We have identified the mating type (MAT) loci in the S. schenckii (strain 1099-18/ATCC MYA-4821) and S. brasiliensis (strain 5110/ATCC MYA-4823) genomes by using comparative genomic approaches to determine the mating type ratio in these pathogen populations. Our analysis revealed the presence of a MAT1-1 locus in S. schenckii while a MAT1-2 locus was found in S. brasiliensis representing genomic synteny to other Sordariomycetes. Furthermore, the components of the mitogen-activated protein kinase (MAPK)-pheromone pathway, pheromone processing enzymes, and meiotic regulators have also been identified in the two pathogens, suggesting the potential for sexual reproduction. The ratio of MAT1-1 to MAT1-2 was not significantly different from 1:1 for all three Sporothrix species, but the population of S. brasiliensis in the outbreaks originated from a single mating type. We also explored the population genetic structure of these pathogens using sequence data of two loci to improve our knowledge of the pattern of geographic distribution, genetic variation, and virulence phenotypes. Population genetics data showed significant population differentiation and clonality with a low level of haplotype diversity in S. brasiliensis isolates from different regions of sporotrichosis outbreaks in Brazil. In contrast, S. schenckii isolates demonstrated a high degree of genetic variability without significant geographic differentiation, indicating the presence of recombination. This study demonstrated that two species causing the same disease have contrasting reproductive strategies and genetic variability

  12. An evolutionary reduction principle for mutation rates at multiple Loci.

    Science.gov (United States)

    Altenberg, Lee

    2011-06-01

    A model of mutation rate evolution for multiple loci under arbitrary selection is analyzed. Results are obtained using techniques from Karlin (Evolutionary Biology, vol. 14, pp. 61-204, 1982) that overcome the weak selection constraints needed for tractability in prior studies of multilocus event models.A multivariate form of the reduction principle is found: reduction results at individual loci combine topologically to produce a surface of mutation rate alterations that are neutral for a new modifier allele. New mutation rates survive if and only if they fall below this surface-a generalization of the hyperplane found by Zhivotovsky et al. (Proc. Natl. Acad. Sci. USA 91, 1079-1083, 1994) for a multilocus recombination modifier. Increases in mutation rates at some loci may evolve if compensated for by decreases at other loci. The strength of selection on the modifier scales in proportion to the number of germline cell divisions, and increases with the number of loci affected. Loci that do not make a difference to marginal fitnesses at equilibrium are not subject to the reduction principle, and under fine tuning of mutation rates would be expected to have higher mutation rates than loci in mutation-selection balance.Other results include the nonexistence of 'viability analogous, Hardy-Weinberg' modifier polymorphisms under multiplicative mutation, and the sufficiency of average transmission rates to encapsulate the effect of modifier polymorphisms on the transmission of loci under selection. A conjecture is offered regarding situations, like recombination in the presence of mutation, that exhibit departures from the reduction principle. Constraints for tractability are: tight linkage of all loci, initial fixation at the modifier locus, and mutation distributions comprising transition probabilities of reversible Markov chains.

  13. Genetic loci for retinal arteriolar microcirculation.

    Directory of Open Access Journals (Sweden)

    Xueling Sim

    Full Text Available Narrow arterioles in the retina have been shown to predict hypertension as well as other vascular diseases, likely through an increase in the peripheral resistance of the microcirculatory flow. In this study, we performed a genome-wide association study in 18,722 unrelated individuals of European ancestry from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium and the Blue Mountain Eye Study, to identify genetic determinants associated with variations in retinal arteriolar caliber. Retinal vascular calibers were measured on digitized retinal photographs using a standardized protocol. One variant (rs2194025 on chromosome 5q14 near the myocyte enhancer factor 2C MEF2C gene was associated with retinal arteriolar caliber in the meta-analysis of the discovery cohorts at genome-wide significance of P-value <5×10(-8. This variant was replicated in an additional 3,939 individuals of European ancestry from the Australian Twins Study and Multi-Ethnic Study of Atherosclerosis (rs2194025, P-value = 2.11×10(-12 in combined meta-analysis of discovery and replication cohorts. In independent studies of modest sample sizes, no significant association was found between this variant and clinical outcomes including coronary artery disease, stroke, myocardial infarction or hypertension. In conclusion, we found one novel loci which underlie genetic variation in microvasculature which may be relevant to vascular disease. The relevance of these findings to clinical outcomes remains to be determined.

  14. Utilization of MatPIV program to different geotechnical models

    Science.gov (United States)

    Aklik, P.; Idinger, G.

    2009-04-01

    The Particle Imaging Velocimetry (PIV) technique is being used to measure soil displacements. PIV has been used for many years in fluid mechanics; but for physical modeling in geotechnical engineering, this technique is still relatively new. PIV is a worldwide growth in soil mechanics over the last decade owing to the developments in digital cameras and laser technologies. The use of PIV is feasible provided the surface contains sufficient texture. A Cambridge group has shown that natural sand contains enough texture for applying PIV. In a texture-based approach, the only requirement is for any patch, big or small to be sufficiently unique so that statistical tracking of this patch is possible. In this paper, some of the soil mechanic's models were investigated such as retaining walls, slope failures, and foundations. The photographs were taken with the help of the high resolution digital camera, the displacements of soils were evaluated with free software named as MatPIV and the displacement graphics between the two images were obtained. Nikon D60 digital camera is 10.2 MB and it has special properties which makes it possible to use in PIV applications. These special properties are Airflow Control System and Image Sensor cleaning for protection against dust, Active D-Lighting for highlighted or shadowy areas while shooting, advanced three-point AF system for fast, efficient and precise autofocus. Its fast and continuous shooting mode enables up to 100 JPEG images at three frames per second. Norm Sand (DIN 1164) was used for all the models in a glass rectangular box. For every experiment, MatPIV was used to calculate the velocities from the two images. MatPIV program was used in two ways such as easy way and difficult way: In the easy way, the two images with 64*64 pixels with 50% or 75% overlap of the interrogation windows were taken into consideration and the calculation was performed with a single iteration through the images and the result consisted of four

  15. Antibacterial electrospun chitosan-polyethylene oxide nanocomposite mats containing ZIF-8 nanoparticles.

    Science.gov (United States)

    Kohsari, Iraj; Shariatinia, Zahra; Pourmortazavi, Seied Mahdi

    2016-10-01

    Antimicrobial chitosan-polyethylene oxide (CS-PEO) nanofiber mats loaded with 3, 5 and 10% (w/w) of zeolitic imidazolate framework-8 nanoparticles (ZIF-8 NPs, ∼60nm diameter) were developed by electrospinning technique. The CS-PEO-GA-3% ZIF-8 NPs crosslinked with glutaraldehyde (GA) vapor was also prepared. The electrospun mats were characterized by various analysis including FE-SEM, EDAX, elemental mapping, FT-IR, contact angle, TGA/DSC as well as tensile strength analysis. The nanofibers had average diameters within the range ∼70-120nm. Antimicrobial activities of the CS-PEO and CS-PEO-3% ZIF-8 mats were evaluated by the viable cell-counting method for determining their effectiveness in reducing or halting the growth of Staphylococcus aureus and Escherichia coli bacteria so that the CS-PEO mat containing 3% ZIF-8 revealed 100% bactericidal activity against both kinds of bacteria. The crosslinked CS-PEO-GA-3% ZIF-8 NPs sample was less thermally stable but more hydrophilic than its related non-crosslinked mat reflecting there was no need to crosslink the fibers using a chemical crosslinker having adverse effects. The highest hydrophobicity and appropriate thermal and tensile properties of CS-PEO-3% ZIF-8 NPs among those of the mats including 5 and 10% ZIF-8 NPs suggested that the mentioned mat is the most suitable sample for food coating applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. A Modeling Comparison of Methanogenesis from Noncompetitive vs Competitive Substrates in a Simulated Hypersaline Microbial Mat

    Science.gov (United States)

    Decker, K. L.; Potter, C.; Hoehler, T.

    2005-12-01

    The well-documented assumption about methanogens that co-occur in hypersaline mat communities with sulfate-reducing bacteria (SRB) is that they rely entirely on non-competitive substrates for methanogenesis. The reason for this is that during sulfate reduction, sulfur-reducing bacteria efficiently utilize H2, leaving a concentration too low for methanogenesis. Early results from recent work on a hypersaline microbial mat from salt evaporation ponds of Guerrero Negro, Baja, Mexico cast doubt that methanogenesis only occurs via non-competitive substrates, because it shows an excess of H2 in the mat rather than a paucity. We explore the use of our simulation model of the microbial biogeochemistry of a hypersaline mat (named MBGC) to compare methane production rates in a 1 cm thick mat when the methanogens use competitive substrates versus noncompetitive substrates. In the `non-competitive substrate' version of the model, methanogens rely exclusively on methylated amines that are accumulated as compatible solutes in cyanobacteria and released after lysis. In contrast, the `competitive substrate' models examine methanogen use of substrates (such as H2 + acetate) with different SRB population sizes (from absent to low). The comparison of these models of methane and sulfide biogeochemistry of a hypersaline mat has both ecological and geobiological significance, as one hypothesis of Archean microbial mats is that they existed in a low sulfate environment.

  17. Increasing Mechanical Properties of 2-D-Structured Electrospun Nylon 6 Non-Woven Fiber Mats

    Directory of Open Access Journals (Sweden)

    Chunhui Xiang

    2016-04-01

    Full Text Available Tensile strength, Young’s modulus, and toughness of electrospun nylon 6 non-woven fiber mats were improved by increasing individual nanofiber strength and fiber–fiber load sharing. Single-walled carbon nanotubes (CNTs were used as reinforcement to increase the strength of the electrospun nylon 6 nanofibers. Young’s modulus, tensile strength, and toughness of the nylon 6 non-woven fiber mats electrospun from 20 wt % solutions increased 51%, 87%, and 136%, respectively, after incorporating 1 wt % CNTs into the nylon 6 nanofibers. Three methods were investigated to enhance fiber–fiber load sharing: increasing friction between fibers, thermal bonding, and solvent bonding. The addition of beaded nylon 6 nanofibers into the non-woven fiber mats to increase fiber-fiber friction resulted in a statistically significantly increase in Young’s modulus over comparable smooth non-woven fiber mats. After annealing, tensile strength, elongation, and toughness of the nylon 6 non-woven fiber mats electrospun from 20 wt % + 10 wt % solutions increased 26%, 28%, and 68% compared to those from 20 wt % solutions. Solvent bonding with formic acid vapor at room temperature for 30 min caused increases of 56%, 67%, and 39% in the Young’s modulus, tensile strength, and toughness of non-woven fiber mats, respectively. The increases attributed to increased individual nanofiber strength and solvent bonding synergistically resulted in the improvement of Young’s modulus of the electrospun nylon 6 non-woven fiber mats.

  18. Organismal and spatial partitioning of energy and macronutrient transformations within a hypersaline mat

    Energy Technology Data Exchange (ETDEWEB)

    Mobberley, Jennifer M.; Lindemann, Stephen R.; Bernstein, Hans C.; Moran, James J.; Renslow, Ryan S.; Babauta, Jerome; Hu, Dehong; Beyenal, Haluk; Nelson, William C.

    2017-03-21

    Phototrophic mat communities are model ecosystems for studying energy cycling and elemental transformations because complete biogeochemical cycles occur over millimeter-to-centimeter scales. Characterization of energy and nutrient capture within hypersaline phototrophic mats has focused on specific processes and organisms, however little is known about community-wide distribution of and linkages between these processes. To investigate energy and macronutrient capture and flow through a structured community, the spatial and organismal distribution of metabolic functions within a compact hypersaline mat community from Hot Lake have been broadly elucidated through species-resolved metagenomics and geochemical, microbial diversity, and metabolic gradient measurements. Draft reconstructed genomes of abundant organisms revealed three dominant cyanobacterial populations differentially distributed across the top layers of the mat suggesting niche separation along light and oxygen gradients. Many organisms contained diverse functional profiles, allowing for metabolic response to changing conditions within the mat. Organisms with partial nitrogen and sulfur metabolisms were widespread indicating dependence upon metabolite exchange. In addition, changes in community spatial structure were observed over the diel. These results indicate that organisms within the mat community have adapted to the temporally dynamic environmental gradients in this hypersaline mat through metabolic flexibility and fluid syntrophic interactions, including shifts in spatial arrangements.

  19. Cantera Integration with the Toolbox for Modeling and Analysis of Thermodynamic Systems (T-MATS)

    Science.gov (United States)

    Lavelle, Thomas M.; Chapman, Jeffryes W.; May, Ryan D.; Litt, Jonathan S.; Guo, Ten-Huei

    2014-01-01

    NASA Glenn Research Center (GRC) has recently developed a software package for modeling generic thermodynamic systems called the Toolbox for the Modeling and Analysis of Thermodynamic Systems (T-MATS). T-MATS is a library of building blocks that can be assembled to represent any thermodynamic system in the Simulink (The MathWorks, Inc.) environment. These elements, along with a Newton Raphson solver (also provided as part of the T-MATS package), enable users to create models of a wide variety of systems. The current version of T-MATS (v1.0.1) uses tabular data for providing information about a specific mixture of air, water (humidity), and hydrocarbon fuel in calculations of thermodynamic properties. The capabilities of T-MATS can be expanded by integrating it with the Cantera thermodynamic package. Cantera is an object-oriented analysis package that calculates thermodynamic solutions for any mixture defined by the user. Integration of Cantera with T-MATS extends the range of systems that may be modeled using the toolbox. In addition, the library of elements released with Cantera were developed using MATLAB native M-files, allowing for quicker prototyping of elements. This paper discusses how the new Cantera-based elements are created and provides examples for using T-MATS integrated with Cantera.

  20. Modification of PLGA Nanofibrous Mats by Electron Beam Irradiation for Soft Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    Jae Baek Lee

    2015-01-01

    Full Text Available Biodegradable poly(lactide-co-glycolide (PLGA has found widespread use in modern medical practice. However, the degradation rate of PLGA should be adjusted for specific biomedical applications such as tissue engineering, drug delivery, and surgical implantation. This study focused on the effect of electron beam radiation on nanofibrous PLGA mats in terms of physical properties and degradation behavior with cell proliferation. PLGA nanofiber mats were prepared by electrospinning, and electron beam was irradiated at doses of 50, 100, 150, 200, 250, and 300 kGy. PLGA mats showed dimensional integrity after electron beam irradiation without change of fiber diameter. The degradation behavior of a control PLGA nanofiber (0 kGy and electron beam-irradiated PLGA nanofibers was analyzed by measuring the molecular weight, weight loss, change of chemical structure, and fibrous morphology. The molecular weight of the PLGA nanofibers decreased with increasing electron beam radiation dose. The mechanical properties of the PLGA nanofibrous mats were decreased with increasing electron beam irradiation dose. Cell proliferation behavior on all electron beam irradiated PLGA mats was similar to the control PLGA mats. Electron beam irradiation of PLGA nanofibrous mats is a potentially useful approach for modulating the biodegradation rate of tissue-specific nonwoven nanofibrous scaffolds, specifically for soft tissue engineering applications.

  1. Low-Light Anoxygenic Photosynthesis and Fe-S-Biogeochemistry in a Microbial Mat.

    Science.gov (United States)

    Haas, Sebastian; de Beer, Dirk; Klatt, Judith M; Fink, Artur; Rench, Rebecca McCauley; Hamilton, Trinity L; Meyer, Volker; Kakuk, Brian; Macalady, Jennifer L

    2018-01-01

    We report extremely low-light-adapted anoxygenic photosynthesis in a thick microbial mat in Magical Blue Hole, Abaco Island, The Bahamas. Sulfur cycling was reduced by iron oxides and organic carbon limitation. The mat grows below the halocline/oxycline at 30 m depth on the walls of the flooded sinkhole. In situ irradiance at the mat surface on a sunny December day was between 0.021 and 0.084 μmol photons m -2 s -1 , and UV light (97% sequence identity) of clones affiliated with Prosthecochloris , a genus within the green sulfur bacteria (GSB), which are obligate anoxygenic phototrophs. Typical photopigments of brown-colored GSB, bacteriochlorophyll e and (β-)isorenieratene, were abundant in mat samples and their absorption properties are well-adapted to harvest light in the available green and possibly even UV-A spectra. Sulfide from the water column (3-6 μmol L -1 ) was the main source of sulfide to the mat as sulfate reduction rates in the mats were very low (undetectable-99.2 nmol cm -3 d -1 ). The anoxic water column was oligotrophic and low in dissolved organic carbon (175-228 μmol L -1 ). High concentrations of pyrite (FeS 2 ; 1-47 μmol cm -3 ) together with low microbial process rates (sulfate reduction, CO 2 fixation) indicate that the mats function as net sulfide sinks mainly by abiotic processes. We suggest that abundant Fe(III) (4.3-22.2 μmol cm -3 ) is the major source of oxidizing power in the mat, and that abiotic Fe-S-reactions play the main role in pyrite formation. Limitation of sulfate reduction by low organic carbon availability along with the presence of abundant sulfide-scavenging iron oxides considerably slowed down sulfur cycling in these mats.

  2. Cross-genus amplification and characterisation of microsatellite loci ...

    African Journals Online (AJOL)

    Jennifer Lamb

    School of Biological and Conservation Sciences, New Biology Building, University of KwaZulu-Natal, University ... These six loci were informative in studies of population genetic structure of C. pumilus ..... The Human Genome Project and the.

  3. Quantile-Based Permutation Thresholds for Quantitative Trait Loci Hotspots

    NARCIS (Netherlands)

    Neto, Elias Chaibub; Keller, Mark P.; Broman, Andrew F.; Attie, Alan D.; Jansen, Ritsert C.; Broman, Karl W.; Yandell, Brian S.; Borevitz, J.

    Quantitative trait loci (QTL) hotspots (genomic locations affecting many traits) are a common feature in genetical genomics studies and are biologically interesting since they may harbor critical regulators. Therefore, statistical procedures to assess the significance of hotspots are of key

  4. Mapping of quantitative trait loci controlling Orobanche foetida Poir ...

    African Journals Online (AJOL)

    Mapping of quantitative trait loci controlling Orobanche foetida Poir. resistance in faba bean (Vicia faba L.) R Díaz-Ruiz, A Torres, MV Gutierrez, D Rubiales, JI Cubero, M Kharrat, Z Satovic, B Román ...

  5. Quantitative trait loci mapping for stomatal traits in interspecific ...

    Indian Academy of Sciences (India)

    M. Sumathi

    2018-02-23

    Feb 23, 2018 ... Journal of Genetics, Vol. ... QTL analysis was carried out to identify the chromosomal regions affecting ... Keywords. linkage map; quantitative trait loci; stomata; stress ..... of India for providing financial support for the project.

  6. Ancient conservation of trinucleotide microsatellite loci in polistine wasps

    DEFF Research Database (Denmark)

    Ezenwa, V O; Peters, J M; Zhu, Y

    1998-01-01

    Microsatellites have proven to be very useful genetic markers for studies of kinship, parentage, and gene mapping. If microsatellites are conserved among species, then those developed for one species can be used on related species, which would save the time and effort of developing new loci. We...... evaluated conservation of 27 trinucleotide loci that were derived from 2 species of Polistes wasps in cross-species applications on 27 species chosen from the major lineages of the Vespidae, which diverged as much as 144 million years ago. We further investigated cross-species polymorphism levels for 18...... of the loci. There was a clear relationship between cladistic distance and both conservation of the priming sites and heterozygosity. However the loci derived from P. bellicosus were much more widely conserved and polymorphic than were those derived from P. annularis. The disparity in cross-species utility...

  7. Cross-genus amplification and characterisation of microsatellite loci ...

    African Journals Online (AJOL)

    Cross-genus amplification and characterisation of microsatellite loci in the little free tailed bat, Chaerephon pumilus s. l. (Molossidae) from South Eastern Africa. Theshnie Naidoo, Angus Macdonald, Jennifer M Lamb ...

  8. Tracing biosignatures from the Recent to the Jurassic in sabkha-associated microbial mats

    Science.gov (United States)

    van der Land, Cees; Dutton, Kirsten; Andrade, Luiza; Paul, Andreas; Sherry, Angela; Fender, Tom; Hewett, Guy; Jones, Martin; Lokier, Stephen W.; Head, Ian M.

    2017-04-01

    Microbial mat ecosystems have been operating at the sediment-fluid interface for over 3400 million years, influencing the flux, transformation and preservation of carbon from the biosphere to the physical environment. These ecosystems are excellent recorders of rapid and profound changes in earth surface environments and biota as they often survive crisis-induced extreme paleoenvironmental conditions. Their biosignatures, captured in the preserved organic matter and the biominerals that form the microbialite rock, constitute a significant tool in understanding geobiological processes and the interactions of the microbial communities with sediments and with the prevailing physical chemical parameters, as well as the environmental conditions at a local and global scale. Nevertheless, the exact pathways of diagenetic organic matter transformation and early-lithification, essential for the accretion and preservation in the geological record as microbialites, are not well understood. The Abu Dhabi coastal sabkha system contains a vast microbial mat belt that is dominated by continuous polygonal and internally-laminated microbial mats across the upper and middle intertidal zones. This modern system is believed to be the best analogue for the Upper Jurassic Arab Formation, which is both a prolific hydrocarbon reservoir and source rock facies in the United Arab Emirates and in neighbouring countries. In order to characterise the processes that lead to the formation of microbialites we investigated the modern and Jurassic system using a multidisciplinary approach, including growth of field-sampled microbial mats under controlled conditions in the laboratory and field-based analysis of microbial communities, mat mineralogy and organic biomarker analysis. In this study, we focus on hydrocarbon biomarker data obtained from the surface of microbial mats actively growing in the intertidal zone of the modern system. By comparing these findings to data obtained from recently

  9. Microbial Mats on the Orkney Islands Revisited: Microenvironment and Microbial Community Composition

    DEFF Research Database (Denmark)

    Wieland, A.; Kühl, M.; McGowan, L.

    2003-01-01

    of these sediments. High amounts of algal lipids and slightly higher numbers (genera, abundances) of cyanobacteria were found in Waulkmill Bay mats. However, overall only a few genera and low numbers of unicellular and filamentous cyanobacteria were present in mats from Waulkmill and Swanbister beach, as deduced...... fragment length polymorphism) analysis in Swanbister beach mats, the depth distribution of different populations of purple and sulfate-reducing bacteria could be related to the microenvironmental conditions. Oxygen, but also sulfide and other (inorganic and organic) sulfur compounds, seems to play...

  10. MAT2B promotes adipogenesis by modulating SAMe levels and activating AKT/ERK pathway during porcine intramuscular preadipocyte differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Cunzhen; Chen, Xiaochang; Wu, Wenjing; Wang, Wusu; Pang, Weijun; Yang, Gongshe, E-mail: gsyang999@hotmail.com

    2016-05-15

    Intramuscular fat (IMF) has been demonstrated as one of the crucial factors of livestock meat quality. The MAT2B protein with MAT2α catalyzes the formation of methyl donor S- adenosylmethionine (SAMe) to mediate cell metabolism including proliferation and apoptosis. However, the regulatory effect of MAT2B on IMF deposition is still unclear. In this study, the effect of MAT2B on adipogenesis and its potential mechanism during porcine intramuscular preadipocyte differentiation was studied. The results showed that overexpression of MAT2B promoted adipogenesis and significantly up-regulated the mRNA and protein levels of adipogenic marker genes including FASN, PPARγ and aP2, consistently, knockdown of MAT2B inhibited lipid accumulation and down-regulated the mRNA and protein levels of the above genes. Furthermore, flow cytometry and EdU-labeling assay indicated that MAT2B regulate adipogenesis was partly due to influence intracellular SAMe levels and further affect cell clonal expansion. Also, increased expression of MAT2B activated the phosphorylations of AKT and ERK1/2, whereas knockdown of MAT2B blocked AKT signaling and repressed the phosphorylation of ERK1/2. Moreover, the inhibitory effect of LY294002 (a specific PI3K inhibitor) on the activities of AKT and ERK1/2 was partially recovered by overexpression of MAT2B in porcine intramuscular adipocytes. Finally, Co-IP experiments showed that MAT2B can directly interact with AKT. Taken together, our findings suggested that MAT2B acted as a positive regulator through modifying SAMe levels as well as activating AKT/ERK signaling pathway to promote porcine intramuscular adipocyte differentiation. - Highlights: • MAT2B up-regulates the expression of adipogenic marker genes and promotes porcine intramuscular preadipocyte differentiation. • MAT2B influences intracellular SAMe levels and further affects cell clonal expansion. • MAT2B interacts with AKT and activates AKT/ERK signaling pathway.

  11. Genius loci jako estetický problém

    OpenAIRE

    Křížová, Lucie

    2016-01-01

    (in English): Diploma thesis Genius loci as an aesthetic problem is addressed by defining the concept of genius loci and exploring its aesthetic implications and parallels. After clarification of the ontological nature of this phenomenon its commonalities will be monitored with selected concepts of environmental philosophy and aesthetics, especially the aesthetic dimension of the environmental experience. Publications of Christian Norberg-Schulz and David E. Cooper are used as a starting mate...

  12. Proactive control of proactive interference using the method of loci

    OpenAIRE

    Bass, Willa S.; Oswald, Karl M.

    2014-01-01

    Proactive interferencebuilds up with exposure to multiple lists of similar items with a resulting reduction in recall. This study examined the effectiveness of using a proactive strategy of the method of loci to reduce proactive interference in a list recall paradigm of categorically similar words. While all participants reported using some form of strategy to recall list words, this study demonstrated that young adults were able to proactively use the method of loci after 25 min of instructi...

  13. Drying Spirulina with Foam Mat Drying at Medium Temperature

    Directory of Open Access Journals (Sweden)

    Aji Prasetyaningrum

    2012-10-01

    Full Text Available Spirulina is a single cell blue green microalgae (Cyanobacteria containing many Phytonutrients (Beta-carotene, Chlorophyl, Xanthophyl, Phyocianin using as anti-carcinogen in food. Producing dry spirulina by quick drying process at medium temperature is very important to retain the Phytonutrient quality. Currently, the work is still challenging due to the gel formation that block the water diffusion from inside to the surface.  This research studies the performance of foam-mat drying on production of dry spirulina. In this method the spirulina was mixed with foaming agent (glair/egg albumen, popular as white egg at 2.5% by weight at air velocity 2.2 m/sec. Here, the effect of spirulina thickness and operational temperature on drying time and quality (Beta-carotene and color were observed. The drying time was estimated based on the measurement of water content in spirulina versus time. Result showed that the thicker spirulina, the longer drying time. Conversely, the higher operational temperature, faster drying time. At thickness ranging 1-3 mm and operational temperature below 70oC, the quality of spirulina can fit the market requirement

  14. Collimation and material science studies (ColMat) at GSI.

    CERN Document Server

    Stadlmann, J; Kollmus, H; Krause, M; Mustafin, E; Petzenhauser, I; Spiller, P; Strasik, I; Tahir, N; Tomut, M; Trautmann, C

    2010-01-01

    Within the frame of the EuCARD program, the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt is performing accelerator R&D in workpackage 8: ColMat. The coordinated effort is focussed on materials aspects important for building the FAIR accelerator facility at GSI and the LHC upgrade at CERN. Accelerator components and especially protection devices have to be operated in high dose environments. The radiation hazard occurs either by the primary proton and ion beams or the secondary radiation after initial beam loss. Detailed numerical simulations have been carried out to study the damage caused to solid targets by the full impact of the LHC beam as well as the SPS beam. Tungsten, copper and graphite as possible collimator materials have been studied. Experimental an theoretical studies on radiation damage on materials used for the LHC upgrade and the FAIR accelerators are performed at the present GSI experimental facilities. Technical decisions based on these results will have an impact on the F...

  15. Hydrogel-Electrospun Fiber Mat Composite Coatings for Neural Prostheses

    Directory of Open Access Journals (Sweden)

    Ning eHan

    2011-03-01

    Full Text Available Achieving stable, long-term performance of implanted neural prosthetic devices has been challenging because of implantation related neuron loss and a foreign body response that results in encapsulating glial scar formation. To improve neuron-prosthesis integration and form chronic, stable interfaces, we investigated the potential of neurotrophin-eluting hydrogel-electrospun fiber mat (EFM composite coatings. In particular, poly(ethylene glycol-poly(ε-caprolactone (PEGPCL hydrogel- poly(ε-caprolactone (PCL EFM composites were applied as coatings for multielectrode arrays (MEAs. Coatings were stable and persisted on electrode surfaces for over 1 month under an agarose gel tissue phantom and over 9 months in a PBS immersion bath. To demonstrate drug release, a neurotrophin, nerve growth factor (NGF, was loaded in the PEGPCL hydrogel layer, and coating cytotoxicity and sustained NGF release were evaluated using a PC12 cell culture model. Quantitative MTT assays showed that these coatings had no significant toxicity toward PC12 cells, and neurite extension at day 7 and 14 confirmed sustained release of NGF at biologically significant concentrations for at least 2 weeks. Our results demonstrate that hydrogel-EFM composite materials can be applied to neural prostheses as a means to improve neuron-electrode proximity and enhance long-term device performance and function.

  16. Laser cleaning of 19th century Congo rattan mats

    International Nuclear Information System (INIS)

    Carmona, N.; Oujja, M.; Roemich, H.; Castillejo, M.

    2011-01-01

    There is a growing interest by art conservators for laser cleaning of organic materials, such as wooden artworks, paper and textiles, since traditional cleaning with solvents can be a source of further decay and mechanical cleaning may be too abrasive for sensitive fibers. In this work we present a successful laser cleaning approach for 19th century rattan mats from the Brooklyn Museum collection of African Art, now part of the study collection at the Conservation Center in New York. Tests were carried out using the fundamental (1064 nm) and second harmonic (532 nm) wavelength of a Q-switched Nd:YAG laser to measure threshold values both for surface damage and color changes for different types of rattan samples. The irradiated substrates were investigated by optical microscopy, scanning electron microscopy and by UV-vis spectroscopy in order to determine the efficiency of laser cleaning and to assess possible deterioration effects that may have occurred as a result of laser irradiation. The study showed that by using the laser emission at 532 nm, a wavelength for which photon energy is below the bond dissociation level of the main cellulosic compounds and the water absorption is negligible, it is possible to select a range of laser fluences to remove the black dust layer without damaging the rattan material.

  17. Soil stabilization mat for lunar launch/landing site

    Science.gov (United States)

    Acord, Amy L.; Cohenour, Mark W.; Ephraim, Daniel; Gochoel, Dennis; Roberts, Jefferson G.

    1990-01-01

    Facilities which are capable of handling frequent arrivals and departures of spaceships between Earth and a lunar colony are necessary. The facility must be able to provide these services with minimal interruption of operational activity within the colony. The major concerns associated with the space traffic are the dust and rock particles that will be kicked up by the rocket exhaust. As a result of the reduced gravitation of the Moon, these particles scatter over large horizontal distances. This flying debris will not only seriously interrupt the routine operations of the colony, but could cause damage to the equipment and facilities surrounding the launch site. An approach to overcome this problem is presented. A proposed design for a lunar take-off/landing mat is presented. This proposal goes beyond dealing with the usual problems of heat and load resistances associated with take-off and landing, by solving the problem of soil stabilization at the site. Through adequate stabilization, the problem of flying debris is eliminated.

  18. Fatigue Characteristic of Chopped Strand Mat/Polyester Composite

    Directory of Open Access Journals (Sweden)

    I Made Astika

    2012-11-01

    Full Text Available The application of composite as an alternatif material to substitute of metal has better properties than metal such as light, high elasticity, corrosion and fatigue resistance. Some components in its application are subjected to millions of varying stress cycles that initiated to fatigue failure such as crack, delamination and fracture. The strength of composite is influenced by construction, fiber type, orientation and fiber fraction. The objective of this experiment is to investigate the fatigue characteristic on SCM composite. Material composite to be used is glass fiber with chopped strand mat (CSM as fiber and Yukalac 157 BQTN-EX with 1% hardener (Mexpox as matrix. The mold process was built with hand lay-up. Fiber volume fractions in composite are 40, 32 and 24 %. The tests to be done on composite are fatigue and tensile test. The research show that the increasing of fiber fraction in composite affects increasing of fatigue life, endurance limit and tensile strength. Fatigue failure modes of composite are debonding, matrix cracking, delamination and fiber fracture.

  19. Photosynthetic and Behavioral Versatility of the Cyanobacterium Oscillatoria-Boryana in a Sulfide-Rich Microbial Mat

    DEFF Research Database (Denmark)

    CASTENHOLZ, RW; JØRGENSEN, BB; DAMELIO, E.

    1991-01-01

    and predominant population which was spread over the mat surface during darkness and on overcast days ( 300 W m-2), O. boryana disappeared almost entirely from the mat surface to a position of about 1 mm below the surface pellicle of the mat. O2, sulfide, and pH microelectrodes inserted into excised mat cores...... photosynthesis of O. boryana occurred. This capability was confirmed for O. boryana by [C-14]-photoincorporation and sulfide-microelectrode experiments. Forced exposure to high irradiance levels (500-700 W m-2) was inhibitory to oxygenic photosynthesis in O. boryana, but these intensities impinging on mats...

  20. Characterization of EST-based SSR loci in the spruce budworm, Choristoneura fumiferana (Lepidoptera: Tortricidae)

    Science.gov (United States)

    B.M.T. Brunet; D. Doucet; B.R. Sturtevant; F.A.H. Sperling

    2013-01-01

    After identifying 114 microsatellite loci from Choristoneura fumiferana expressed sequence tags, 87 loci were assayed in a panel of 11 wild-caught individuals, giving 29 polymorphic loci. Further analysis of 20 of these loci on 31 individuals collected from a single population in northern Minnesota identified 14 in Hardy-Weinberg equilibrium.

  1. Unravelling Colletotrichum species associated with Camellia: employing ApMat and GS loci to resolve species in the C. gloeosporioides complex

    NARCIS (Netherlands)

    Liu, F.; Weir, B.S.; Damm, U.; Crous, P.W.; Wang, Y.; Liu, B.; Wang, M.; Zhang, M.; Cai, L.

    2015-01-01

    "We investigated the phylogenetic diversity of 144 Colletotrichum isolates associated with symptomatic and asymptomatic tissues of Camellia sinensis and other Camellia spp. from seven provinces in China (Fujian, Guizhou, Henan, Jiangxi, Sichuan, Yunnan, Zhejiang), and seven isolates obtained from

  2. Unravelling Colletotrichum species associated with Camellia: employing ApMat and GS loci to resolve species in the C. gloeosporioides complex

    NARCIS (Netherlands)

    Liu, F; Weir, B S; Damm, U; Crous, P W; Wang, Y; Liu, B; Wang, M; Zhang, M; Cai, L

    2015-01-01

    We investigated the phylogenetic diversity of 144 Colletotrichum isolates associated with symptomatic and asymptomatic tissues of Camellia sinensis and other Camellia spp. from seven provinces in China (Fujian, Guizhou, Henan, Jiangxi, Sichuan, Yunnan, Zhejiang), and seven isolates obtained from

  3. VocMat projekt - uudsed e-õppe võimalused turismiasjalistele / Heli Tooman

    Index Scriptorium Estoniae

    Tooman, Heli, 1949-

    2008-01-01

    Turismivaldkonna spetsialistidele mõeldud koolitusprojektist VocMat (Vocational Management Training for the Tourism Industry). Projekti partneriteks Eestis on Ettevõtluse Arendamise Sihtasutuse Turismiarenduskeskus ja Tartu Ülikooli Pärnu kolledzh. Lisa: Kokkuvõte

  4. Biocidal Activity of Plasma Modified Electrospun Polysulfone Mats Functionalized with Polyethyleneimine-Capped Silver Nanoparticles

    KAUST Repository

    Schiffman, Jessica D.; Wang, Yue; Giannelis, Emmanuel P.; Elimelech, Menachem

    2011-01-01

    loss of bacteria (Escherichia coli) viability. Time-dependent bacterial cytotoxicity studies indicate that the optimized PSf-AgNP mats exhibit a high level of inactivation against both Gram negative bacteria, Escherichia coli, and Gram positive bacteria

  5. Halloysite nanotube-based electrospun ceramic nanofibre mat: a novel support for zeolite membranes

    Science.gov (United States)

    Chen, Zhuwen; Zeng, Jiaying; Lv, Dong; Gao, Jinqiang; Zhang, Jian; Bai, Shan; Li, Ruili; Hong, Mei; Wu, Jingshen

    2016-12-01

    Some key parameters of supports such as porosity, pore shape and size are of great importance for fabrication and performance of zeolite membranes. In this study, we fabricated millimetre-thick, self-standing electrospun ceramic nanofibre mats and employed them as a novel support for zeolite membranes. The nanofibre mats were prepared by electrospinning a halloysite nanotubes/polyvinyl pyrrolidone composite followed by a programmed sintering process. The interwoven nanofibre mats possess up to 80% porosity, narrow pore size distribution, low pore tortuosity and highly interconnected pore structure. Compared with the commercial α-Al2O3 supports prepared by powder compaction and sintering, the halloysite nanotube-based mats (HNMs) show higher flux, better adsorption of zeolite seeds, adhesion of zeolite membranes and lower Al leaching. Four types of zeolite membranes supported on HNMs have been successfully synthesized with either in situ crystallization or a secondary growth method, demonstrating good universality of HNMs for supporting zeolite membranes.

  6. Synthesis of CuAlO2 nanofibrous mats by electrospinning

    International Nuclear Information System (INIS)

    Zhao Shizhen; Li Miaoyu; Liu Xiaomin; Han Gaoyi

    2009-01-01

    Electrospinning as a versatile method for preparation of nanofibers has been used to fabricate the polyvinylalcohol nanofibers containing equal molar of aluminum nitrate and copper acetate. After pretreated at 400 deg. C, the composite fibrous mats were annealed at 1100 deg. C in air for 5 h and then the delafossite-structured p-type CuAlO 2 ceramics fibrous mats were obtained. The obtained CuAlO 2 ceramics fibrous mats were characterized by scanning electrical microscope, X-ray diffraction and diffuse reflectance spectroscopy. The direct energy gap of the prepared CuAlO 2 ceramics fibrous mats was measured to be about 3.38 eV. The CuAlO 2 behaved like semiconductors and the thermally activated energy was about 0.25 eV.

  7. Temperature dependent transport and dielectric properties of cadmium titanate nanofiber mats

    Directory of Open Access Journals (Sweden)

    Z. Imran

    2013-03-01

    Full Text Available We investigate electrical and dielectric properties of cadmium titanate (CdTiO3 nanofiber mats prepared by electrospinning. The nanofibers were polycrystalline having diameter ∼50 nm-200 nm, average length ∼100 μm and crystallite size ∼25 nm. Alternating current impedance measurements were carried out from 318 K – 498 K. The frequency of ac signal was varied from 2 – 105 Hz. The complex impedance plots revealed two depressed semicircular arcs indicating the bulk and interface contribution to overall electrical behavior of nanofiber mats. The bulk resistance was found to increase with decrease in temperature exhibiting typical semiconductor like behavior. The modulus analysis shows the non-Debye type conductivity relaxation in nanofiber mats. The ac conductivity spectrum obeyed the Jonscher power law. Analysis of frequency dependent ac conductivity revealed presence of the correlated barrier hopping (CBH in nanofiber mats over the entire temperature range.

  8. A niche for cyanobacteria producing chlorophyll f within a microbial mat.

    Science.gov (United States)

    Ohkubo, Satoshi; Miyashita, Hideaki

    2017-10-01

    Acquisition of additional photosynthetic pigments enables photosynthetic organisms to survive in particular niches. To reveal the ecological significance of chlorophyll (Chl) f, we investigated the distribution of Chl and cyanobacteria within two microbial mats. In a 7-mm-thick microbial mat beneath the running water of the Nakabusa hot spring, Japan, Chl f was only distributed 4.0-6.5 mm below the surface, where the intensity of far-red light (FR) was higher than that of photosynthetically active radiation (PAR). In the same mat, two ecotypes of Synechococcus and two ecotypes of Chl f-producing Leptolyngbya were detected in the upper and deeper layers, respectively. Only the Leptolyngbya strains could grow when FR was the sole light source. These results suggest that the deeper layer of the microbial mat was a habitat for Chl f-producing cyanobacteria, and Chl f enabled them to survive in a habitat with little PAR.

  9. production and cost of cold patch road mats with bitumen extracted

    African Journals Online (AJOL)

    Jamiu

    This paper reports the production of bituminous road mats with bitumen sourced from the Nigerian Tar sand, recycled .... scrap tires are produced every year, which makes the disposal of ..... particles will be round or nearly round and will pass.

  10. Marine Microbial Mats and the Search for Evidence of Life in Deep Time and Space

    Science.gov (United States)

    Des Marais, David J.

    2011-01-01

    Cyanobacterial mats in extensive seawater evaporation ponds at Guerrero Negro, Baja California, Mexico, have been excellent subjects for microbial ecology research. The studies reviewed here have documented the steep and rapidly changing environmental gradients experienced by mat microorganisms and the very high rates of biogeochemical processes that they maintained. Recent genetic studies have revealed an enormous diversity of bacteria as well as the spatial distribution of Bacteria, Archaea and Eukarya. These findings, together with emerging insights into the intimate interactions between these diverse populations, have contributed substantially to our understanding of the origins, environmental impacts, and biosignatures of photosynthetic microbial mats. The biosignatures (preservable cells, sedimentary fabrics, organic compounds, minerals, stable isotope patterns, etc.) potentially can serve as indicators of past life on early Earth. They also can inform our search for evidence of any life on Mars. Mars exploration has revealed evidence of evaporite deposits and thermal spring deposits; similar deposits on Earth once hosted ancient microbial mat ecosystems.

  11. Controls on O2 Production in Cyanobacterial Mats and Implications for Earth's Oxygenation

    Science.gov (United States)

    Dick, Gregory J.; Grim, Sharon L.; Klatt, Judith M.

    2018-05-01

    Cyanobacterial mats are widely assumed to have been globally significant hot spots of biogeochemistry and evolution during the Archean and Proterozoic, but little is known about their quantitative contributions to global primary productivity or Earth's oxygenation. Modern systems show that mat biogeochemistry is the outcome of concerted activities and intimate interactions between various microbial metabolisms. Emerging knowledge of the regulation of oxygenic and sulfide-driven anoxygenic photosynthesis by versatile cyanobacteria, and their interactions with sulfur-oxidizing bacteria and sulfate-reducing bacteria, highlights how ecological and geochemical processes can control O2 production in cyanobacterial mats in unexpected ways. This review explores such biological controls on O2 production. We argue that the intertwined effects of light availability, redox geochemistry, regulation and competition of microbial metabolisms, and biogeochemical feedbacks result in emergent properties of cyanobacterial mat communities that are all critical yet largely overlooked mechanisms to potentially explain the protracted nature of Earth's oxygenation.

  12. Fabrication and In Vitro/In Vivo Performance of Mucoadhesive Electrospun Nanofiber Mats Containing α-Mangostin.

    Science.gov (United States)

    Samprasit, Wipada; Rojanarata, Theerasak; Akkaramongkolporn, Prasert; Ngawhirunpat, Tanasait; Kaomongkolgit, Ruchadaporn; Opanasopit, Praneet

    2015-10-01

    This study aimed to fabricate mucoadhesive electrospun nanofiber mats containing α-mangostin for the maintenance of oral hygiene and reduction of the bacterial growth that causes dental caries. Synthesized thiolated chitosan (CS-SH) blended with polyvinyl alcohol (PVA) was selected as the mucoadhesive polymer. α-Mangostin was incorporated into the CS-SH/PVA solution and electrospun to obtain nanofiber mats. Scanning electron microscopy, differential scanning calorimetry, X-ray diffraction, and tensile strength testing were used to characterize the mats. The swelling degree and mucoadhesion were also determined. The nanofiber mats were further evaluated regarding their α-mangostin content, in vitro α-mangostin release, antibacterial activity, cytotoxicity, in vivo performance, and stability. The results indicated that the mats were in the nanometer range. The α-mangostin was well incorporated into the mats, with an amorphous form. The mats showed suitable tensile strength, swelling, and mucoadhesive properties. The loading capacity increased when the initial amount of α-mangostin was increased. Rapid release of α-mangostin from the mats was achieved. Additionally, a fast bacterial killing rate occurred at the lowest concentration of nanofiber mats when α-mangostin was added to the mats. The mats were less cytotoxic after use for 72 h. Moreover, in vivo testing indicated that the mats could reduce the number of oral bacteria, with a good mouth feel. The mats maintained the amount of α-mangostin for 6 months. The results suggest that α-mangostin-loaded mucoadhesive electrospun nanofiber mats may be a promising material for oral care and the prevention of dental caries.

  13. Sway Area and Velocity Correlated With MobileMat Balance Error Scoring System (BESS) Scores.

    Science.gov (United States)

    Caccese, Jaclyn B; Buckley, Thomas A; Kaminski, Thomas W

    2016-08-01

    The Balance Error Scoring System (BESS) is often used for sport-related concussion balance assessment. However, moderate intratester and intertester reliability may cause low initial sensitivity, suggesting that a more objective balance assessment method is needed. The MobileMat BESS was designed for objective BESS scoring, but the outcome measures must be validated with reliable balance measures. Thus, the purpose of this investigation was to compare MobileMat BESS scores to linear and nonlinear measures of balance. Eighty-eight healthy collegiate student-athletes (age: 20.0 ± 1.4 y, height: 177.7 ± 10.7 cm, mass: 74.8 ± 13.7 kg) completed the MobileMat BESS. MobileMat BESS scores were compared with 95% area, sway velocity, approximate entropy, and sample entropy. MobileMat BESS scores were significantly correlated with 95% area for single-leg (r = .332) and tandem firm (r = .474), and double-leg foam (r = .660); and with sway velocity for single-leg (r = .406) and tandem firm (r = .601), and double-leg (r = .575) and single-leg foam (r = .434). MobileMat BESS scores were not correlated with approximate or sample entropy. MobileMat BESS scores were low to moderately correlated with linear measures, suggesting the ability to identify changes in the center of mass-center of pressure relationship, but not higher-order processing associated with nonlinear measures. These results suggest that the MobileMat BESS may be a clinically-useful tool that provides objective linear balance measures.

  14. Polymer solution, fiber mat, and nanofiber membrane-electrode-assembly therewith, and method of fabricating same

    DEFF Research Database (Denmark)

    2016-01-01

    of fibers. The fibers may further include particles of a catalyst. The fiber mat may be used to form an electrode or a membrane. In a further aspect, a fuel cell membrane-electrode-assembly has an anode electrode, a cathode electrode, and a membrane disposed between the anode electrode and the cathode...... electrode. Each of the anode electrode, the cathode electrode and the membrane may be formed with a fiber mat....

  15. Physicochemical characterization of different trademarks of compound Yerba Maté and their herbs

    OpenAIRE

    Scipioni,Griselda Patricia; Ferreyra,Darío Jorge; Schmalko,Miguel Eduardo

    2007-01-01

    The objectives of this study were to evaluate the physicochemical characteristics of the main herbs used in the mixture of yerba maté with other aromatic herbs and the characterization of the trademarks of compound yerba maté. Moisture, water extract, total ash, acid-insoluble ash and caffeine concentration were determined. Results showed higher values of moisture content, total and aci-insoluble ash and lower water extracts in the herbs. Determinations were carried out in nine trademarks of ...

  16. Engineering and Scientific Applications: Using MatLab(Registered Trademark) for Data Processing and Visualization

    Science.gov (United States)

    Sen, Syamal K.; Shaykhian, Gholam Ali

    2011-01-01

    MatLab(TradeMark)(MATrix LABoratory) is a numerical computation and simulation tool that is used by thousands Scientists and Engineers in many countries. MatLab does purely numerical calculations, which can be used as a glorified calculator or interpreter programming language; its real strength is in matrix manipulations. Computer algebra functionalities are achieved within the MatLab environment using "symbolic" toolbox. This feature is similar to computer algebra programs, provided by Maple or Mathematica to calculate with mathematical equations using symbolic operations. MatLab in its interpreter programming language form (command interface) is similar with well known programming languages such as C/C++, support data structures and cell arrays to define classes in object oriented programming. As such, MatLab is equipped with most of the essential constructs of a higher programming language. MatLab is packaged with an editor and debugging functionality useful to perform analysis of large MatLab programs and find errors. We believe there are many ways to approach real-world problems; prescribed methods to ensure foregoing solutions are incorporated in design and analysis of data processing and visualization can benefit engineers and scientist in gaining wider insight in actual implementation of their perspective experiments. This presentation will focus on data processing and visualizations aspects of engineering and scientific applications. Specifically, it will discuss methods and techniques to perform intermediate-level data processing covering engineering and scientific problems. MatLab programming techniques including reading various data files formats to produce customized publication-quality graphics, importing engineering and/or scientific data, organizing data in tabular format, exporting data to be used by other software programs such as Microsoft Excel, data presentation and visualization will be discussed.

  17. Fermentation couples Chloroflexi and sulfate-reducing bacteria to Cyanobacteria in hypersaline microbial mats

    Directory of Open Access Journals (Sweden)

    Jackson Z Lee

    2014-02-01

    Full Text Available Past studies of hydrogen cycling in hypersaline microbial mats have shown an active nighttime cycle, with production largely from Cyanobacteria and consumption from sulfate-reducing bacteria (SRB. However, the mechanisms and magnitude of hydrogen cycling have not been extensively studied. Two mats types near Guerrero Negro, Mexico -- permanently submerged Microcoleus microbial mats (GN-S, and intertidal Lyngbya microbial mats (GN-I -- were used in microcosm diel manipulation experiments with 3-(3,4-dichlorophenyl-1,1-dimethylurea (DCMU, molybdate, ammonium addition, and physical disruption to understand the processes responsible for hydrogen cycling between mat microbes. Across microcosms, H2 production occurred under dark anoxic conditions with simultaneous production of a suite of organic acids. H2 production was not significantly affected by inhibition of nitrogen fixation, but rather appears to result from constitutive fermentation of photosynthetic storage products by oxygenic phototrophs. Comparison to accumulated glycogen and to CO2 flux indicated that, in the GN-I mat, fermentation released almost all of the carbon fixed via photosynthesis during the preceding day, primarily as organic acids. Across mats, although oxygenic and anoxygenic phototrophs were detected, cyanobacterial [NiFe]-hydrogenase transcripts predominated. Molybdate inhibition experiments indicated that SRBs from a wide distribution of dsrA phylotypes were responsible for H2 consumption. Incubation with 13C-acetate and nanoSIMS (secondary ion mass-spectrometry indicated higher uptake in both Chloroflexi and SRBs relative to other filamentous bacteria. These manipulations and diel incubations confirm that Cyanobacteria were the main fermenters in Guerrero Negro mats and that the net flux of nighttime fermentation byproducts (not only hydrogen was largely regulated by the interplay between Cyanobacteria, SRBs, and Chloroflexi.

  18. Community structure and function of high-temperature chlorophototrophic microbial mats inhabiting diverse geothermal environments

    DEFF Research Database (Denmark)

    Klatt, Christian G.; Inskeep, William P.; Herrgard, Markus

    2013-01-01

    Six phototrophic microbial mat communities from different geothermal springs (YNP) were studied using metagenome sequencing and geochemical analyses. The primary goals of this work were to determine differences in community composition of high-temperature phototrophic mats distributed across...... the Yellowstone geothermal ecosystem, and to identify metabolic attributes of predominant organisms present in these communities that may correlate with environmental attributes important in niche differentiation. Random shotgun metagenome sequences from six phototrophic communities (average 53Mbp/site) were...

  19. Multiple loci associated with renal function in African Americans.

    Directory of Open Access Journals (Sweden)

    Daniel Shriner

    Full Text Available The incidence of chronic kidney disease varies by ethnic group in the USA, with African Americans displaying a two-fold higher rate than European Americans. One of the two defining variables underlying staging of chronic kidney disease is the glomerular filtration rate. Meta-analysis in individuals of European ancestry has identified 23 genetic loci associated with the estimated glomerular filtration rate (eGFR. We conducted a follow-up study of these 23 genetic loci using a population-based sample of 1,018 unrelated admixed African Americans. We included in our follow-up study two variants in APOL1 associated with end-stage kidney disease discovered by admixture mapping in admixed African Americans. To address confounding due to admixture, we estimated local ancestry at each marker and global ancestry. We performed regression analysis stratified by local ancestry and combined the resulting regression estimates across ancestry strata using an inverse variance-weighted fixed effects model. We found that 11 of the 24 loci were significantly associated with eGFR in our sample. The effect size estimates were not significantly different between the subgroups of individuals with two copies of African ancestry vs. two copies of European ancestry for any of the 11 loci. In contrast, allele frequencies were significantly different at 10 of the 11 loci. Collectively, the 11 loci, including four secondary signals revealed by conditional analyses, explained 14.2% of the phenotypic variance in eGFR, in contrast to the 1.4% explained by the 24 loci in individuals of European ancestry. Our findings provide insight into the genetic basis of variation in renal function among admixed African Americans.

  20. Enhancing the mechanical properties of electrospun polyester mats by heat treatment

    Directory of Open Access Journals (Sweden)

    M. Kancheva

    2015-01-01

    Full Text Available Microfibrous materials with a targeted design based on poly(L-lactic acid (PLA and poly(ε-caprolactone (PCL were prepared by electrospinning and by combining electrospinning and electrospraying. Several approaches were used: (i electrospinning of a common solution of the two polymers, (ii simultaneous electrospinning of two separate solutions of PLA and PCL, (iii electrospinning of PLA solution in conjunction with electrospraying of PCL solution, and (iv alternating layer-by-layer deposition by electrospinning of separate PLA and PCL solutions. The mats were heated at the melting temperature of PCL (60°", thus achieving melting of PCL fibers/particles and thermal sealing of the fibers. The mats subjected to thermal treatment were characterized by greater mean fiber diameters and reduced values of the water contact angle compared to the pristine mats. Heat treatment of the mats affected their thermal stability and led to an increase in the crystallinity degree of PLA incorporated in the mats, whereas that of PCL was reduced. All mats were characterized by enhanced mechanical properties after thermal treatment as compared to the non-treated fibrous materials.

  1. Electron microscopy study of microbial mat in the North Fiji basin hydrothermal vent

    Science.gov (United States)

    Park, H.; Kim, J. W.; Lee, J. W.

    2017-12-01

    Hydrothermal vent systems consisting of hydrothermal vent, hydrothermal sediment and microbial mat are widely spread around the ocean, particularly spreading axis, continental margin and back-arc basin. Scientists have perceived that the hydrothermal systems, which reflect the primeval earth environment, are one of the best places to reveal the origin of life and extensive biogeochemical process of microbe-mineral interaction. In the present study multiline of analytical methods (X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM)) were utilized to investigate the mineralogy/chemistry of microbe-mineral interaction in hydrothermal microbial mat. Microbial mat samples were recovered by Canadian scientific submersible ROPOS on South Pacific North Fiji basin KIOST hydrothermal vent expedition 1602. XRD analysis showed that red-colored microbial mat contains Fe-oxides and Fe-oxyhydroxides. Various morphologies of minerals in the red-colored microbial mat observed by SEM are mainly showed sheath shaped, resembled with Leptothrix microbial structure, stalks shaped, similar with Marioprofundus microbial structure and globule shaped microbial structures. They are also detected with DNA analysis. The cross sectional observation of microbial structures encrusted with Fe-oxide and Fe-oxyhydroxide at a nano scale by Transmission Electron Microscopy (TEM) and Focused Ion Beam (FIB) technique was developed to verify the structural/biogeochemical properties in the microbe-mineral interaction. Systematic nano-scale measurements on the biomineralization in the microbial mat leads the understandings of biogeochemical environments around the hydrothermal vent.

  2. Mechanical Properties of Natural Jute Fabric/Jute Mat Fiber Reinforced Polymer Matrix Hybrid Composites

    Directory of Open Access Journals (Sweden)

    Elsayed A. Elbadry

    2012-01-01

    Full Text Available Recycled needle punched jute fiber mats as a first natural fiber reinforcement system and these jute mats used as a core needle punched with recycled jute fabric cloths as skin layers as a second natural fiber reinforcement system were used for unsaturated polyester matrix composites via modifying the hand lay-up technique with resin preimpregnation into the jute fiber in vacuum. The effect of skin jute fabric on the tensile and bending properties of jute mat composites was investigated for different fiber weight contents. Moreover, the notch sensitivity of these composites was also compared by using the characteristic distance do calculated by Finite Element Method (FEM. The results showed that the tensile and flexural properties of jute mat composites increased by increasing the fiber weight content and by adding the jute fabric as skin layers. On the other hand, by adding the skins, the characteristic distance decreased and, therefore, the notch sensitivity of the composites increased. The fracture behavior investigated by SEM showed that extensive fiber pull-out mechanism was revealed at the tension side of jute mat composites under the bending load and by adding the jute cloth, the failure mode of jute mat was changed to fiber bridge mechanism.

  3. Sequester of metals and mineralization of organic contaminants with microbial mats

    International Nuclear Information System (INIS)

    Bender, J.; Phillips, P.; Gould, J.P.

    1995-01-01

    Several recalcitrant organic contaminants are completely mineralized to simple products by microbial mats. Contaminants include chlordane, PCB, TNT, petroleum distillates, BM compounds and TCE in a mixed contaminant solution containing Zn. Degradation rates are relatively rapid under both dark and light conditions. In addition to complete degradation of organic materials, mats have been used to reduce selenate to elemental selenium, remove Pb, Cd, Cu, Zn, Co, Cr, Fe and Mn from water and sequester uranium (U 238 ) at a rate of 3.19 mg/m 2 /h. Results of three pilot projects, including field pond treatment of mine drainage and bioreactor treatment of BTEX compounds will be reported. Microbial mats are natural heterotrophic and autotrophic communities dominated by cyanobacteria (blue-green algae). They are self-organized laminated structures annealed fightly together by slimy secretions from various microbial components. The surface slime of the mats effectively immobilizes the ecosystem to a variety of substrates, thereby stabilizing the most efficient internal microbial structure. Cyanobacteria mats are generated for bioremediation applications by enriching a water surface with ensiled grass clippings together with mat inocula developed in the laboratory

  4. Vitamin E-loaded silk fibroin nanofibrous mats fabricated by green process for skin care application.

    Science.gov (United States)

    Sheng, Xiaoyue; Fan, Linpeng; He, Chuanglong; Zhang, Kuihua; Mo, Xiumei; Wang, Hongsheng

    2013-05-01

    In the present study, we reported fabrication and skin benefit of a novel vitamin E (VE)-loaded silk fibroin (SF) nanofibrous mats. RRR-α-Tocopherol polyethylene glycol 1000 succinate (VE TPGS), a water-soluble derivative of VE, was incorporated into SF nanofiber successfully by aqua solution electrospinning for the first time. Morphology of the composite nanofibers changed with the different amount of VE TPGS: a ribbon-like shape for lower loading dose of VE TPGS, while a round shape for higher loading dose (more than 4% (wt/wt) based on the weight of SF). After treated with 75% (v/v) ethanol vapor, the composite nanofibrous mats showed an excellent water-resistant ability. In vitro study disclosed a sustained release behavior of VE TPGS disassociated from the nanofibrous mats. The mouse skin fibroblasts (L929 cells) cultured on the VE-loaded SF nanofibrous mats spread and proliferated much better than on cover slips. Moreover, the incorporation of VE TPGS was found strengthening the ability of SF nanofibrous mats on protecting the cells against oxidation stress induced by tert-butyl hydroperoxide. Our data presented impressive skin benefits of this VE-loaded SF nanofibrous mats, suggesting a promising applicative potential of this novel product on personal skin care, tissue regeneration and other related area. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Protein and Bacterial Antifouling Behavior of Melt-Coextruded Nanofiber Mats.

    Science.gov (United States)

    Kim, Si-Eun; Zhang, Cong; Advincula, Abigail A; Baer, Eric; Pokorski, Jonathan K

    2016-04-13

    Antifouling surfaces are important for biomedical devices to prevent secondary infections and mitigate the effects of the foreign body response. Herein, we describe melt-coextruded poly(ε-caprolactone) (PCL) nanofiber mats grafted with antifouling polymers. Nonwoven PCL fiber mats are produced using a multilayered melt coextrusion process followed by high-pressure hydroentanglement to yield porous patches. The resulting fiber mats show submicrometer cross-sectional fiber dimensions and yield pore sizes that were nearly uniform, with a mean pore size of 1.6 ± 0.9 μm. Several antifouling polymers, including hydrophilic, zwitterionic, and amphipathic molecules, are grafted to the surface of the mats using a two-step procedure that includes photochemistry followed by the copper-catalyzed azide-alkyne cycloaddition reaction. Fiber mats are evaluated using separate adsorption tests for serum proteins and E. coli. The results indicate that poly(oligo(ethylene glycol) methyl ether methacrylate)-co-(trifluoroethyl methacrylate) (poly(OEGMEMA-co-TFEMA)) grafted mats exhibit approximately 85% less protein adhesion and 97% less E. coli adsorption when compared to unmodified PCL fibermats. In dynamic antifouling testing, the amphiphilic fluorous polymer surface shows the highest flux and highest rejection value of foulants. The work presented within has implications on the high-throughput production of antifouling microporous patches for medical applications.

  6. Enhanced dechlorination of trichloroethylene using electrospun polymer nanofibrous mats immobilized with iron/palladium bimetallic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Hui [State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620 (China); College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Huang, Yunpeng; Shen, Mingwu; Guo, Rui; Cao, Xueyan [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Shi, Xiangyang, E-mail: xshi@dhu.edu.cn [State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620 (China); College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); CQM - Centro de Quimica da Madeira, Universidade da Madeira, Campus da Penteada, 9000-390 Funchal (Portugal)

    2012-04-15

    Fe/Pd bimetallic nanoparticles (NPs) have held great promise for treating trichloroethylene (TCE)-contaminated groundwater, without the accumulation of chlorinated intermediates. However, the conventionally used colloidal Fe/Pd NPs usually aggregate rapidly, resulting in a reduced reactivity. To reduce the particle aggregation, we employed electrospun polyacrylic acid (PAA)/polyvinyl alcohol (PVA) polymer nanofibers as a nanoreactor to immobilize Fe/Pd bimetallic NPs. In the study, the water-stable PAA/PVA nanofibrous mats were complexed with Fe (III) ions via the binding with the free carboxyl groups of PAA for subsequent formation and immobilization of zero-valent iron (ZVI) NPs. Fe/Pd bimetallic NPs were then formed by the partial reduction of Pd(II) ions with ZVI NPs. The formed electrospun nanofibrous mats containing Fe/Pd bimetallic NPs with a diameter of 2.8 nm were characterized by scanning electron microscopy, energy-dispersive spectroscopy, transmission electron microscopy, thermogravimetric analysis, and inductively coupled plasma-atomic emission spectroscopy. The Fe/Pd NP-containing electrospun PAA/PVA nanofibrous mats exhibited higher reactivity than that of the ZVI NP-containing mats or colloidal Fe/Pd NPs in the dechlorination of trichloroethylene (TCE), which was used as a model contaminant. With the high surface area to volume ratio, high porosity, and great reusability of the fibrous mats immobilized with the bimetallic NPs, the composite nanofibrous mats should be amenable for applications in remediation of various environmental contaminants.

  7. Enhanced dechlorination of trichloroethylene using electrospun polymer nanofibrous mats immobilized with iron/palladium bimetallic nanoparticles

    International Nuclear Information System (INIS)

    Ma, Hui; Huang, Yunpeng; Shen, Mingwu; Guo, Rui; Cao, Xueyan; Shi, Xiangyang

    2012-01-01

    Fe/Pd bimetallic nanoparticles (NPs) have held great promise for treating trichloroethylene (TCE)-contaminated groundwater, without the accumulation of chlorinated intermediates. However, the conventionally used colloidal Fe/Pd NPs usually aggregate rapidly, resulting in a reduced reactivity. To reduce the particle aggregation, we employed electrospun polyacrylic acid (PAA)/polyvinyl alcohol (PVA) polymer nanofibers as a nanoreactor to immobilize Fe/Pd bimetallic NPs. In the study, the water-stable PAA/PVA nanofibrous mats were complexed with Fe (III) ions via the binding with the free carboxyl groups of PAA for subsequent formation and immobilization of zero-valent iron (ZVI) NPs. Fe/Pd bimetallic NPs were then formed by the partial reduction of Pd(II) ions with ZVI NPs. The formed electrospun nanofibrous mats containing Fe/Pd bimetallic NPs with a diameter of 2.8 nm were characterized by scanning electron microscopy, energy-dispersive spectroscopy, transmission electron microscopy, thermogravimetric analysis, and inductively coupled plasma-atomic emission spectroscopy. The Fe/Pd NP-containing electrospun PAA/PVA nanofibrous mats exhibited higher reactivity than that of the ZVI NP-containing mats or colloidal Fe/Pd NPs in the dechlorination of trichloroethylene (TCE), which was used as a model contaminant. With the high surface area to volume ratio, high porosity, and great reusability of the fibrous mats immobilized with the bimetallic NPs, the composite nanofibrous mats should be amenable for applications in remediation of various environmental contaminants.

  8. Regulation of mat responses by a differentiation MAPK pathway in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Sheelarani Karunanithi

    Full Text Available Fungal species exhibit diverse behaviors when presented with extracellular challenges. Pathogenic fungi can undergo cell differentiation and biofilm formation in response to fluctuating nutrient levels, and these responses are required for virulence. In the model fungal eukaryote Saccharomyces cerevisiae, nutrient limitation induces filamentous growth and biofilm/mat formation. Both responses require the same signal transduction (MAPK pathway and the same cell adhesion molecule (Flo11 but have been studied under different conditions. We found that filamentous growth and mat formation are aspects of a related response that is regulated by the MAPK pathway. Cells in yeast-form mats differentiated into pseudohyphae in response to nutrient limitation. The MAPK pathway regulated mat expansion (in the plane of the XY-axis and substrate invasion (downward in the plane of the Z-axis, which optimized the mat's response to extracellular nutrient levels. The MAPK pathway also regulated an upward growth pattern (in the plane of the Z-axis in response to nutrient limitation and changes in surface rigidity. Upward growth allowed for another level of mat responsiveness and resembled a type of colonial chemorepulsion. Together our results show that signaling pathways play critical roles in regulating social behaviors in which fungal cells participate. Signaling pathways may regulate similar processes in pathogens, whose highly nuanced responses are required for virulence.

  9. Fabrication and Characterization of Electrospun Polycaprolactone Blended with Chitosan-Gelatin Complex Nanofibrous Mats

    Directory of Open Access Journals (Sweden)

    Yongfang Qian

    2014-01-01

    Full Text Available Design and fabrication of nanofibrous scaffolds should mimic the native extracellular matrix. This study is aimed at investigating electrospinning of polycaprolactone (PCL blended with chitosan-gelatin complex. The morphologies were observed from scanning electron microscope. As-spun blended mats had thinner fibers than pure PCL. X-ray diffraction was used to analyze the degree of crystallinity. The intensity at two peaks at 2θ of 21° and 23.5° gradually decreased with the percentage of chitosan-gelatin complex increasing. Moreover, incorporation of the complex could obviously improve the hydrophilicity of as-spun blended mats. Mechanical properties of as-spun nanofibrous mats were also tested. The elongation at break of fibrous mats increased with the PCL content increasing and the ultimate tensile strength varied with different weight ratios. The as-spun mats had higher tensile strength when the weight ratio of PCL to CS-Gel was 75/25 compared to pure PCL. Both as-spun PCL scaffolds and PCL/CS-Gel scaffolds supported the proliferation of porcine iliac endothelial cells, and PCL/CS-Gel had better cell viability than pure PCL. Therefore, electrospun PCL/Chitosan-gelatin nanofibrous mats with weight ratio of 75/25 have better hydrophilicity mechanical properties, and cell proliferation and thus would be a promising candidate for tissue engineering scaffolds.

  10. Late Archean mineralised cyanobacterial mats and their modern analogs

    Science.gov (United States)

    Kazmierczak, J.; Altermann, W.; Kremer, B.; Kempe, S.; Eriksson, P. G.

    2008-09-01

    ,c) reminiscent of common sheaths (glycocalix), typical for coccoidal colonial (pseudoparenchymatous) entophysalidacean or pleurocapsalean cyanobacteria (Fig. 2d-f). The remains of the coccoid sheaths and capsules are visible as a system of rimmed subglobular or irregularly polygonal pits separated from adjacent pits by 2-3 μm thick walls. Microprobe analyses show that the interiors of the pits are composed of almost pure calcium carbonate whereas the rims and walls of calcium carbonate with high admixture of silicates (mostly Al-Fe clay-like silicates) and dolomite. High magnification images of rims and walls confirm the microprobe data indicating authigenic character of the minerals forming both the carbonate infilling the pits interiors (CaCO3) and their rims and walls (CaCO3 + Al-Fe silicates + dolomite). EPSC Abstracts, Vol. 3, EPSC2008-A-00493, 2008 European Planetary Science Congress, Author(s) 2008 It seems that carbonates were the first mineral phase filling the spaces remained after the plasmolysis of the cyanobacterial cell contents, whereas the formation of silicates within the exopolysaccharides forming the bulk of the sheaths and capsules was a later diagenetic process. Microprobe analyses of mineralised modern coccoid cyanobacterial mats forming tower-like structures in the highly alkaline Lake Van, Turkey [3,4] display a set of elements indicative for the presence of authigenic carbonate and silicate minerals which are almost identical with that occurring in the studied Neoarchean samples. Also the optical and SEM images of polished and etched platelets of permineralised Lake Van microbialites are strikingly similar (Fig. 2d-f). Similarly as in modern cyanobacterial and other microbial mats, the process of early post mortem mineralisation, in the case of the Nauga Formation, was most probably associated with the action of heterotrophic bacteria upon the dead cyanobacterial biomass. Heterotrophic bacteria occupying EPS layers of living and dead cyanobacterial

  11. High-density genotyping of immune loci in Koreans and Europeans identifies eight new rheumatoid arthritis risk loci.

    Science.gov (United States)

    Kim, Kwangwoo; Bang, So-Young; Lee, Hye-Soon; Cho, Soo-Kyung; Choi, Chan-Bum; Sung, Yoon-Kyoung; Kim, Tae-Hwan; Jun, Jae-Bum; Yoo, Dae Hyun; Kang, Young Mo; Kim, Seong-Kyu; Suh, Chang-Hee; Shim, Seung-Cheol; Lee, Shin-Seok; Lee, Jisoo; Chung, Won Tae; Choe, Jung-Yoon; Shin, Hyoung Doo; Lee, Jong-Young; Han, Bok-Ghee; Nath, Swapan K; Eyre, Steve; Bowes, John; Pappas, Dimitrios A; Kremer, Joel M; Gonzalez-Gay, Miguel A; Rodriguez-Rodriguez, Luis; Ärlestig, Lisbeth; Okada, Yukinori; Diogo, Dorothée; Liao, Katherine P; Karlson, Elizabeth W; Raychaudhuri, Soumya; Rantapää-Dahlqvist, Solbritt; Martin, Javier; Klareskog, Lars; Padyukov, Leonid; Gregersen, Peter K; Worthington, Jane; Greenberg, Jeffrey D; Plenge, Robert M; Bae, Sang-Cheol

    2015-03-01

    A highly polygenic aetiology and high degree of allele-sharing between ancestries have been well elucidated in genetic studies of rheumatoid arthritis. Recently, the high-density genotyping array Immunochip for immune disease loci identified 14 new rheumatoid arthritis risk loci among individuals of European ancestry. Here, we aimed to identify new rheumatoid arthritis risk loci using Korean-specific Immunochip data. We analysed Korean rheumatoid arthritis case-control samples using the Immunochip and genome-wide association studies (GWAS) array to search for new risk alleles of rheumatoid arthritis with anticitrullinated peptide antibodies. To increase power, we performed a meta-analysis of Korean data with previously published European Immunochip and GWAS data for a total sample size of 9299 Korean and 45,790 European case-control samples. We identified eight new rheumatoid arthritis susceptibility loci (TNFSF4, LBH, EOMES, ETS1-FLI1, COG6, RAD51B, UBASH3A and SYNGR1) that passed a genome-wide significance threshold (p<5×10(-8)), with evidence for three independent risk alleles at 1q25/TNFSF4. The risk alleles from the seven new loci except for the TNFSF4 locus (monomorphic in Koreans), together with risk alleles from previously established RA risk loci, exhibited a high correlation of effect sizes between ancestries. Further, we refined the number of single nucleotide polymorphisms (SNPs) that represent potentially causal variants through a trans-ethnic comparison of densely genotyped SNPs. This study demonstrates the advantage of dense-mapping and trans-ancestral analysis for identification of potentially causal SNPs. In addition, our findings support the importance of T cells in the pathogenesis and the fact of frequent overlap of risk loci among diverse autoimmune diseases. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  12. Low-Light Anoxygenic Photosynthesis and Fe-S-Biogeochemistry in a Microbial Mat

    Directory of Open Access Journals (Sweden)

    Sebastian Haas

    2018-04-01

    Full Text Available We report extremely low-light-adapted anoxygenic photosynthesis in a thick microbial mat in Magical Blue Hole, Abaco Island, The Bahamas. Sulfur cycling was reduced by iron oxides and organic carbon limitation. The mat grows below the halocline/oxycline at 30 m depth on the walls of the flooded sinkhole. In situ irradiance at the mat surface on a sunny December day was between 0.021 and 0.084 μmol photons m-2 s-1, and UV light (<400 nm was the most abundant part of the spectrum followed by green wavelengths (475–530 nm. We measured a light-dependent carbon uptake rate of 14.5 nmol C cm-2 d-1. A 16S rRNA clone library of the green surface mat layer was dominated (74% by a cluster (>97% sequence identity of clones affiliated with Prosthecochloris, a genus within the green sulfur bacteria (GSB, which are obligate anoxygenic phototrophs. Typical photopigments of brown-colored GSB, bacteriochlorophyll e and (β-isorenieratene, were abundant in mat samples and their absorption properties are well-adapted to harvest light in the available green and possibly even UV-A spectra. Sulfide from the water column (3–6 μmol L-1 was the main source of sulfide to the mat as sulfate reduction rates in the mats were very low (undetectable-99.2 nmol cm-3 d-1. The anoxic water column was oligotrophic and low in dissolved organic carbon (175–228 μmol L-1. High concentrations of pyrite (FeS2; 1–47 μmol cm-3 together with low microbial process rates (sulfate reduction, CO2 fixation indicate that the mats function as net sulfide sinks mainly by abiotic processes. We suggest that abundant Fe(III (4.3–22.2 μmol cm-3 is the major source of oxidizing power in the mat, and that abiotic Fe-S-reactions play the main role in pyrite formation. Limitation of sulfate reduction by low organic carbon availability along with the presence of abundant sulfide-scavenging iron oxides considerably slowed down sulfur cycling in these mats.

  13. Live visualization of genomic loci with BiFC-TALE.

    Science.gov (United States)

    Hu, Huan; Zhang, Hongmin; Wang, Sheng; Ding, Miao; An, Hui; Hou, Yingping; Yang, Xiaojing; Wei, Wensheng; Sun, Yujie; Tang, Chao

    2017-01-11

    Tracking the dynamics of genomic loci is important for understanding the mechanisms of fundamental intracellular processes. However, fluorescent labeling and imaging of such loci in live cells have been challenging. One of the major reasons is the low signal-to-background ratio (SBR) of images mainly caused by the background fluorescence from diffuse full-length fluorescent proteins (FPs) in the living nucleus, hampering the application of live cell genomic labeling methods. Here, combining bimolecular fluorescence complementation (BiFC) and transcription activator-like effector (TALE) technologies, we developed a novel method for labeling genomic loci (BiFC-TALE), which largely reduces the background fluorescence level. Using BiFC-TALE, we demonstrated a significantly improved SBR by imaging telomeres and centromeres in living cells in comparison with the methods using full-length FP.

  14. New Microsatellite Loci for Prosopis alba and P. chilensis (Fabaceae

    Directory of Open Access Journals (Sweden)

    Cecilia F. Bessega

    2013-05-01

    Full Text Available Premise of the study: As only six useful microsatellite loci that exhibit broad cross-amplification are so far available for Prosopis species, it is necessary to develop a larger number of codominant markers for population genetic studies. Simple sequence repeat (SSR markers obtained for Prosopis species from a 454 pyrosequencing run were optimized and characterized for studies in P. alba and P. chilensis. Methods and Results: Twelve markers that were successfully amplified showed polymorphism in P. alba and P. chilensis. The number of alleles per locus ranged between two and seven and heterozygosity estimates ranged from 0.2 to 0.8. Most of these loci cross-amplify in P. ruscifolia, P. flexuosa, P. kuntzei, P. glandulosa, and P. pallida. Conclusions: These loci will enable genetic diversity studies of P. alba and P. chilensis and contribute to fine-scale population structure, indirect estimation of relatedness among individuals, and marker-assisted selection.

  15. New microsatellite loci for Prosopis alba and P. chilensis (Fabaceae).

    Science.gov (United States)

    Bessega, Cecilia F; Pometti, Carolina L; Miller, Joe T; Watts, Richard; Saidman, Beatriz O; Vilardi, Juan C

    2013-05-01

    As only six useful microsatellite loci that exhibit broad cross-amplification are so far available for Prosopis species, it is necessary to develop a larger number of codominant markers for population genetic studies. Simple sequence repeat (SSR) markers obtained for Prosopis species from a 454 pyrosequencing run were optimized and characterized for studies in P. alba and P. chilensis. • Twelve markers that were successfully amplified showed polymorphism in P. alba and P. chilensis. The number of alleles per locus ranged between two and seven and heterozygosity estimates ranged from 0.2 to 0.8. Most of these loci cross-amplify in P. ruscifolia, P. flexuosa, P. kuntzei, P. glandulosa, and P. pallida. • These loci will enable genetic diversity studies of P. alba and P. chilensis and contribute to fine-scale population structure, indirect estimation of relatedness among individuals, and marker-assisted selection.

  16. Proactive control of proactive interference using the method of loci.

    Science.gov (United States)

    Bass, Willa S; Oswald, Karl M

    2014-01-01

    Proactive interferencebuilds up with exposure to multiple lists of similar items with a resulting reduction in recall. This study examined the effectiveness of using a proactive strategy of the method of loci to reduce proactive interference in a list recall paradigm of categorically similar words. While all participants reported using some form of strategy to recall list words, this study demonstrated that young adults were able to proactively use the method of loci after 25 min of instruction to reduce proactive interference as compared with other personal spontaneous strategies. The implications of this study are that top-down proactive strategies such as the method of loci can significantly reduce proactive interference, and that the use of image and sequence or location are especially useful in this regard.

  17. Novel multiple sclerosis susceptibility loci implicated in epigenetic regulation.

    Science.gov (United States)

    Andlauer, Till F M; Buck, Dorothea; Antony, Gisela; Bayas, Antonios; Bechmann, Lukas; Berthele, Achim; Chan, Andrew; Gasperi, Christiane; Gold, Ralf; Graetz, Christiane; Haas, Jürgen; Hecker, Michael; Infante-Duarte, Carmen; Knop, Matthias; Kümpfel, Tania; Limmroth, Volker; Linker, Ralf A; Loleit, Verena; Luessi, Felix; Meuth, Sven G; Mühlau, Mark; Nischwitz, Sandra; Paul, Friedemann; Pütz, Michael; Ruck, Tobias; Salmen, Anke; Stangel, Martin; Stellmann, Jan-Patrick; Stürner, Klarissa H; Tackenberg, Björn; Then Bergh, Florian; Tumani, Hayrettin; Warnke, Clemens; Weber, Frank; Wiendl, Heinz; Wildemann, Brigitte; Zettl, Uwe K; Ziemann, Ulf; Zipp, Frauke; Arloth, Janine; Weber, Peter; Radivojkov-Blagojevic, Milena; Scheinhardt, Markus O; Dankowski, Theresa; Bettecken, Thomas; Lichtner, Peter; Czamara, Darina; Carrillo-Roa, Tania; Binder, Elisabeth B; Berger, Klaus; Bertram, Lars; Franke, Andre; Gieger, Christian; Herms, Stefan; Homuth, Georg; Ising, Marcus; Jöckel, Karl-Heinz; Kacprowski, Tim; Kloiber, Stefan; Laudes, Matthias; Lieb, Wolfgang; Lill, Christina M; Lucae, Susanne; Meitinger, Thomas; Moebus, Susanne; Müller-Nurasyid, Martina; Nöthen, Markus M; Petersmann, Astrid; Rawal, Rajesh; Schminke, Ulf; Strauch, Konstantin; Völzke, Henry; Waldenberger, Melanie; Wellmann, Jürgen; Porcu, Eleonora; Mulas, Antonella; Pitzalis, Maristella; Sidore, Carlo; Zara, Ilenia; Cucca, Francesco; Zoledziewska, Magdalena; Ziegler, Andreas; Hemmer, Bernhard; Müller-Myhsok, Bertram

    2016-06-01

    We conducted a genome-wide association study (GWAS) on multiple sclerosis (MS) susceptibility in German cohorts with 4888 cases and 10,395 controls. In addition to associations within the major histocompatibility complex (MHC) region, 15 non-MHC loci reached genome-wide significance. Four of these loci are novel MS susceptibility loci. They map to the genes L3MBTL3, MAZ, ERG, and SHMT1. The lead variant at SHMT1 was replicated in an independent Sardinian cohort. Products of the genes L3MBTL3, MAZ, and ERG play important roles in immune cell regulation. SHMT1 encodes a serine hydroxymethyltransferase catalyzing the transfer of a carbon unit to the folate cycle. This reaction is required for regulation of methylation homeostasis, which is important for establishment and maintenance of epigenetic signatures. Our GWAS approach in a defined population with limited genetic substructure detected associations not found in larger, more heterogeneous cohorts, thus providing new clues regarding MS pathogenesis.

  18. Isolation of human simple repeat loci by hybridization selection.

    Science.gov (United States)

    Armour, J A; Neumann, R; Gobert, S; Jeffreys, A J

    1994-04-01

    We have isolated short tandem repeat arrays from the human genome, using a rapid method involving filter hybridization to enrich for tri- or tetranucleotide tandem repeats. About 30% of clones from the enriched library cross-hybridize with probes containing trimeric or tetrameric tandem arrays, facilitating the rapid isolation of large numbers of clones. In an initial analysis of 54 clones, 46 different tandem arrays were identified. Analysis of these tandem repeat loci by PCR showed that 24 were polymorphic in length; substantially higher levels of polymorphism were displayed by the tetrameric repeat loci isolated than by the trimeric repeats. Primary mapping of these loci by linkage analysis showed that they derive from 17 chromosomes, including the X chromosome. We anticipate the use of this strategy for the efficient isolation of tandem repeats from other sources of genomic DNA, including DNA from flow-sorted chromosomes, and from other species.

  19. A PQL (protein quantity loci) analysis of mature pea seed proteins identifies loci determining seed protein composition.

    Science.gov (United States)

    Bourgeois, Michael; Jacquin, Françoise; Cassecuelle, Florence; Savois, Vincent; Belghazi, Maya; Aubert, Grégoire; Quillien, Laurence; Huart, Myriam; Marget, Pascal; Burstin, Judith

    2011-05-01

    Legume seeds are a major source of dietary proteins for humans and animals. Deciphering the genetic control of their accumulation is thus of primary significance towards their improvement. At first, we analysed the genetic variability of the pea seed proteome of three genotypes over 3 years of cultivation. This revealed that seed protein composition variability was under predominant genetic control, with as much as 60% of the spots varying quantitatively among the three genotypes. Then, by combining proteomic and quantitative trait loci (QTL) mapping approaches, we uncovered the genetic architecture of seed proteome variability. Protein quantity loci (PQL) were searched for 525 spots detected on 2-D gels obtained for 157 recombinant inbred lines. Most protein quantity loci mapped in clusters, suggesting that the accumulation of the major storage protein families was under the control of a limited number of loci. While convicilin accumulation was mainly under the control of cis-regulatory regions, vicilins and legumins were controlled by both cis- and trans-regulatory regions. Some loci controlled both seed protein composition and protein content and a locus on LGIIa appears to be a major regulator of protein composition and of protein in vitro digestibility. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. UV B-induced vertical migrations of cyanobacteria in a microbial mat

    International Nuclear Information System (INIS)

    Rebout, B.M.; Garcia-Pichel, F.

    1995-01-01

    Exposure to moderate doses of UV B (0.35 to 0.79 W m -2 s -1 or 0.98 to 2.2 μmol of photons m -2 s -1 at 310 nm) caused the surface layers of microbial mats from Solar Lake, Sinai, Egypt, to become visibly lighter green. Concurrent with the color change were rapid and dramatic reductions in gross photosynthesis and in the resultant high porewater oxygen concentrations in the surface layers of the mats. The depths at which both maximum gross photosynthesis and maximum oxygen concentrations occurred were displaced downward. In contrast, gross photosynthesis in the deeper layers of the mats increased in response to UV B incident upon the surface. The cessation of exposure to UV B partially reversed all of these changes. Taken together, these responses suggest that photoautotrophic members of the mat community, most likely the dominant cyanobacterium Microcoleus chthonoplastes, were migrating in response to the added UV B. The migration phenomenon was also observed in response to increases in visible radiation and UV A, but UV B was ca. 100-fold more effective than visible radiation and ca. 20-fold more effective than UV A in provoking the response. Migrating microorganisms within this mat are apparently able to sense UV B directly and respond behaviorally to limit their exposure to UV. Because of strong vertical gradients of light and dissolved substances in microbial mats, the migration and the resultant vertical redistribution of photosynthetic activity have important consequences for both the photobiology of the cyanobacteria and the net primary productivity of the mat ecosystem

  1. Assembly and Succession of Iron Oxide Microbial Mat Communities in Acidic Geothermal Springs

    Directory of Open Access Journals (Sweden)

    Jacob P. Beam

    2016-02-01

    Full Text Available Biomineralized ferric oxide microbial mats are ubiquitous features on Earth, are common in hot springs of Yellowstone National Park (YNP, WY, USA, and form due to direct interaction between microbial and physicochemical processes. The overall goal of this study was to determine the contribution of different community members to the assembly and succession of acidic high-temperature Fe(III-oxide mat ecosystems. Spatial and temporal changes in Fe(III-oxide accretion and the abundance of relevant community members were monitored over 70 days using sterile glass microscope slides incubated in the outflow channels of two acidic geothermal springs (pH = 3 - 3.5; temperature = 68 - 75 °C in YNP. Hydrogenobaculum spp. were the most abundant taxon identified during early successional stages (4 - 40 d, and have been shown to oxidize arsenite, sulfide, and hydrogen coupled to oxygen reduction. Iron-oxidizing populations of Metallosphaera yellowstonensis were detected within 4 d, and reached steady-state levels within 14 - 30 d, corresponding to visible Fe(III-oxide accretion. Heterotrophic archaea colonized near 30 d, and emerged as the dominant functional guild after 70 d and in mature Fe(III-oxide mats (1 - 2 cm thick. First-order rate constants of Fe(III-oxide accretion ranged from 0.046 - 0.05 d-1, and in situ microelectrode measurements showed that the oxidation of Fe(II is limited by the diffusion of O2 into the Fe(III-oxide mat. The formation of microterracettes also implicated O2 as a major variable controlling microbial growth and subsequent mat morphology. The assembly and succession of Fe(III-oxide mat communities follows a repeatable pattern of colonization by lithoautotrophic organisms, and the subsequent growth of diverse organoheterotrophs. The unique geochemical signatures and micromorphology of extant biomineralized Fe(III-oxide mats are useful for understanding other Fe(II-oxidizing systems.

  2. Confirmation of novel type 1 diabetes risk loci in families

    DEFF Research Database (Denmark)

    Cooper, J D; Howson, J M M; Smyth, D

    2012-01-01

    Over 50 regions of the genome have been associated with type 1 diabetes risk, mainly using large case/control collections. In a recent genome-wide association (GWA) study, 18 novel susceptibility loci were identified and replicated, including replication evidence from 2,319 families. Here, we......, the Type 1 Diabetes Genetics Consortium (T1DGC), aimed to exclude the possibility that any of the 18 loci were false-positives due to population stratification by significantly increasing the statistical power of our family study....

  3. Strategie di spazializzazione dei contenuti nel GeniusLoci Digitale

    Directory of Open Access Journals (Sweden)

    Davide Gasperi

    2013-07-01

    Full Text Available GeniusLoci Digitale is a software architecture of virtual tour that integrates various multimedia technologies (3D computer graphics, panoramas, dynamic maps, movies, pictures to represent the identity of places. The designer is interested in reproducing virtually complex aspects that define a context, which means the effect of meaning that distinguishes one place. GeniusLoci Digitale is in fact an architecture that evolves in search of a reproductive and communicative function which is recognizable to extend its development to the Open Source community.

  4. Effects of tacky mat contamination on bond degradation for Chemlok/liner and NBR/liner bonds

    Science.gov (United States)

    Padilla, A. M.

    1989-01-01

    Tacky mats are placed by the rubber lay-up areas for the solid rocket motor segments. These mats dust off the shoes prior to entering the platform where the lay-up work is performed. The possibility exists that a tacky mat could be touched with gloved hands prior to handling the uncured nitride butadiene rubber (NBR). Tests were run to determine if NBR were accidentally touched would there be any degradation of the liner/NBR bond. The tacky mats were judged solely on the basis of bond degradation caused by either direct or indirect contamination. Test results all indicate that there was no notable NBR/Chemlok or liner/NBR bond degradation on samples that came into contact with the tacky mat material. Testing procedures are described. The tacky mat adhesive composition does not contain fluorocarbons or release agents that would affect bonding.

  5. Microsatellite loci discovery from next-generation sequencing data and loci characterization in the epizoic barnacle Chelonibia testudinaria (Linnaeus, 1758

    Directory of Open Access Journals (Sweden)

    Christine Ewers-Saucedo

    2016-05-01

    Full Text Available Microsatellite markers remain an important tool for ecological and evolutionary research, but are unavailable for many non-model organisms. One such organism with rare ecological and evolutionary features is the epizoic barnacle Chelonibia testudinaria (Linnaeus, 1758. Chelonibia testudinaria appears to be a host generalist, and has an unusual sexual system, androdioecy. Genetic studies on host specificity and mating behavior are impeded by the lack of fine-scale, highly variable markers, such as microsatellite markers. In the present study, we discovered thousands of new microsatellite loci from next-generation sequencing data, and characterized 12 loci thoroughly. We conclude that 11 of these loci will be useful markers in future ecological and evolutionary studies on C. testudinaria.

  6. Microsatellite loci discovery from next-generation sequencing data and loci characterization in the epizoic barnacle Chelonibia testudinaria (Linnaeus, 1758)

    Science.gov (United States)

    Zardus, John D.; Wares, John P.

    2016-01-01

    Microsatellite markers remain an important tool for ecological and evolutionary research, but are unavailable for many non-model organisms. One such organism with rare ecological and evolutionary features is the epizoic barnacle Chelonibia testudinaria (Linnaeus, 1758). Chelonibia testudinaria appears to be a host generalist, and has an unusual sexual system, androdioecy. Genetic studies on host specificity and mating behavior are impeded by the lack of fine-scale, highly variable markers, such as microsatellite markers. In the present study, we discovered thousands of new microsatellite loci from next-generation sequencing data, and characterized 12 loci thoroughly. We conclude that 11 of these loci will be useful markers in future ecological and evolutionary studies on C. testudinaria. PMID:27231653

  7. Photosynthetic microbial mats today, on early Earth, (and on early Mars?)

    Science.gov (United States)

    Des Marais, D. J.

    2008-05-01

    Marine hypersaline cyanobacterial mats offer insights about their ancient ancestors, whose fossil record is 3.43 billion years old. Studies of mat microbiota have greatly expanded the known diversity of ancient microbial lineages. Their evolution was shaped by mat microenvironments, which can differ substantially from their surroundings. Oxygenic photosynthesis perhaps developed in microbial mats and probably triggered a major evolutionary transformation and diversification of the early biosphere. Gross primary production rates in cyanobacterial mats can rival the most productive ecosystems known. Sunlight changes in intensity and spectral composition as it penetrates mats, and counteracting gradients of O2 and sulfide shape the chemical microenvironment. A combination of benefits and hazards of light, O2 and sulfide promotes the allocation of the various essential mat processes between light and dark periods and to various depths in the mat. Close inspection has revealed surprises, for example: anoxygenic phototrophs inside cyanobacterial sheaths, record- high sulfate reduction rates in O2-saturated conditions, and high H2 fluxes into overlying waters. Diverse organic biomarker compounds have been documented that are amenable to long-term preservation. Such coordinated observations of populations, processes and products are making fundamental questions in ecology accessible. Cyanobacterial mats have robust fossil records in part because they populated stable continental platforms and margins, contributing to sediments having high preservation potential. Proterozoic cyanobacterial fossils and organic biomarkers are well documented. The 3.43 Ga Strelley Pool cherts, W. Australia, reveal diverse stromatolites that populated a partially restricted, low-energy shallow hypersaline basin. Molecular studies of extant bacteria hint that early chlorophyll-utilizing photosynthesizers required geochemical sources of reductants. Did these anoxygenic phototrophs once sustain an

  8. Isolation and characterization of eight novel microsatellite loci in the double-crested cormorant (Phalacrocorax auritus)

    Science.gov (United States)

    Mercer, Dacey; Haig, Susan; Mullins, Thomas

    2010-01-01

    We describe the isolation and characterization of eight microsatellite loci from the double-crested cormorant (Phalacrocorax auritus). Genetic variability was assessed using 60 individuals from three populations. All loci were variable with the number of alleles ranging from two to 17 per locus, and observed heterozygosity varying from 0.05 to 0.89. No loci showed signs of linkage disequilibrium and all loci conformed to Hardy–Weinberg equilibrium frequencies. Further, all loci amplified and were polymorphic in two related Phalacrocorax species. These loci should prove useful for population genetic studies of the double-crested cormorant and other pelecaniform species.

  9. Sewage, green algal mats anchored by lugworms, and the effects on Turbellaria and small Polychaeta

    Science.gov (United States)

    Reise, Karsten

    1983-06-01

    On sandy tidal flats at the Island of Sylt (North Sea) ephemeral mats of green algae covered wide areas in the vicinity of sewage outflows. Algae became anchored in the feeding funnels of lugworms ( Arenicola marina) and thus were able to resist displacement by tidal currents. Below the algal mats anoxic conditions extend to the sediment surface. After about one month a rough sea removed all algae. Polychaetes endured this short-term environmental deterioration, while the more sensitive Turbellaria decreased in abundance and species richness. Diatom-feeders were affected most, predators to a medium extent, and bacteria-feeders the least affected. Rare and very abundant species were more affected than moderately abundant ones. None of the turbellarian species increased in abundance and none colonized the algal mats above the sediment. In a semicontrolled experiment with daily hand-removal of drift algae from a 100-m2 plot within an extensive field of algal mats, this cleaned "island" served as a refuge to Turbellaria escaping from their algal covered habitat. Here abundance doubled relative to initial conditions and was 5-times higher than below algal mats.

  10. Russian Army Mat as a Code System Controlling Behaviour in the Russian army

    Directory of Open Access Journals (Sweden)

    Vadim Mikhailin

    2004-09-01

    Full Text Available This text is to be a shortened, restructured and based on somewhat another factological foundation version of my article “Russkii mat kak muzhskoi obstsennyi kod: problema proiskhozhdeniia i evoliutsiia statusa”, published in # 43 of Novoe Literaturnoe Obozrenie. Tracing the genesis of mat to the specific modes of behaviour, peculiar to the archaic male warrior bands, I’m going to show that the military milieu (and some other, structurally close to it social strata, has always been – and remain – absolutely adequate for the mat speaking. Moreover, mat has always carried on within these strata rather specific function connected with creating of one’s identity as a military, and its use offers various and sometimes the only possible means of impact at one’s equal or subordinate (or even superior. As a matter of fact, mat is a basis for a whole code system, controlling different military behaviour practices. The problems of the freshers’ adaptation and of the national specificities in the late Soviet and modern Russian army are to be considered with special respect.

  11. Biogeochemistry of an iron-rich hypersaline microbial mat (Camargue, France).

    Science.gov (United States)

    Wieland, A; Zopfi, J; Benthien, M; Kühl, M

    2005-01-01

    In situ microsensor measurements were combined with biogeochemical methods to determine oxygen, sulfur, and carbon cycling in microbial mats growing in a solar saltern (Salin-de-Giraud, France). Sulfate reduction rates closely followed the daily temperature changes and were highest during the day at 25 degrees C and lowest during the night at 11 degrees C, most probably fueled by direct substrate interactions between cyanobacteria and sulfate-reducing bacteria. Sulfate reduction was the major mineralization process during the night and the contribution of aerobic respiration to nighttime DIC production decreased. This decrease of aerobic respiration led to an increasing contribution of sulfide (and iron) oxidation to nighttime O2 consumption. A peak of elemental sulfur in a layer of high sulfate reduction at low sulfide concentration underneath the oxic zone indicated anoxygenic photosynthesis and/or sulfide oxidation by iron, which strongly contributed to sulfide consumption. We found a significant internal carbon cycling in the mat, and sulfate reduction directly supplied DIC for photosynthesis. The mats were characterized by a high iron content of 56 micromol Fe cm(-3), and iron cycling strongly controlled the sulfur cycle in the mat. This included sulfide precipitation resulting in high FeS contents with depth, and reactions of iron oxides with sulfide, especially after sunset, leading to a pronounced gap between oxygen and sulfide gradients and an unusual persistence of a pH peak in the uppermost mat layer until midnight.

  12. Rapid Reactivation of Cyanobacterial Photosynthesis and Migration upon Rehydration of Desiccated Marine Microbial Mats

    KAUST Repository

    Chennu, Arjun

    2015-12-24

    Desiccated cyanobacterial mats are the dominant biological feature in the Earth’s arid zones. While the response of desiccated cyanobacteria to rehydration is well-documented for terrestrial systems, information about the response in marine systems is lacking. We used high temporal resolution hyperspectral imaging, liquid chromatography, pulse-amplitude fluorometry, oxygen microsensors, and confocal laser microscopy to study this response in a desiccated microbial mat from Exmouth Gulf, Australia. During the initial 15 min after rehydration chlorophyll a concentrations increased 2–5 fold and cyanobacterial photosynthesis was re-established. Although the mechanism behind this rapid increase of chlorophyll a remains unknown, we hypothesize that it involves resynthesis from a precursor stored in desiccated cyanobacteria. The subsequent phase (15 min–48 h) involved migration of the reactivated cyanobacteria toward the mat surface, which led, together with a gradual increase in chlorophyll a, to a further increase in photosynthesis. We conclude that the response involving an increase in chlorophyll a and recovery of photosynthetic activity within minutes after rehydration is common for cyanobacteria from desiccated mats of both terrestrial and marine origin. However, the response of upward migration and its triggering factor appear to be mat-specific and likely linked to other factors.

  13. Rapid reactivation of cyanobacterial photosynthesis and migration upon rehydration of desiccated marine microbial mats

    Directory of Open Access Journals (Sweden)

    Arjun eChennu

    2015-12-01

    Full Text Available Desiccated cyanobacterial mats are the dominant biological feature in the Earth's arid zones. While the response of desiccated cyanobacteria to rehydration is well documented for terrestrial systems, information about the response in marine systems is lacking. We used high temporal resolution hyperspectral imaging, liquid chromatography, pulse-amplitude fluorometry, oxygen microsensors and confocal laser microscopy to study this response in a desiccated microbial mat from Exmouth Gulf, Australia. During the initial 15 minutes after rehydration chlorophyll a concentrations increased 2-5 fold and cyanobacterial photosynthesis was re-established. Although the mechanism behind this rapid increase of chlorophyll a remains unknown, we hypothesize that it involves resynthesis from a precursor stored in desiccated cyanobacteria. The subsequent phase (15 min – 48 h involved migration of the reactivated cyanobacteria towards the mat surface, which led, together with a gradual increase in chlorophyll a, to a further increase in photosynthesis. We conclude that the response involving an increase in chlorophyll a and recovery of photosynthetic activity within minutes after rehydration is common for cyanobacteria from desiccated mats of both terrestrial and aquatic origin. However the response of upward migration and its triggering factor appears to be mat-specific and likely linked to other factors.

  14. A Process for the Creation of T-MATS Propulsion System Models from NPSS data

    Science.gov (United States)

    Chapman, Jeffryes W.; Lavelle, Thomas M.; Litt, Jonathan S.; Guo, Ten-Huei

    2014-01-01

    A modular thermodynamic simulation package called the Toolbox for the Modeling and Analysis of Thermodynamic Systems (T-MATS) has been developed for the creation of dynamic simulations. The T-MATS software is designed as a plug-in for Simulink (Math Works, Inc.) and allows a developer to create system simulations of thermodynamic plants (such as gas turbines) and controllers in a single tool. Creation of such simulations can be accomplished by matching data from actual systems, or by matching data from steady state models and inserting appropriate dynamics, such as the rotor and actuator dynamics for an aircraft engine. This paper summarizes the process for creating T-MATS turbo-machinery simulations using data and input files obtained from a steady state model created in the Numerical Propulsion System Simulation (NPSS). The NPSS is a thermodynamic simulation environment that is commonly used for steady state gas turbine performance analysis. Completion of all the steps involved in the process results in a good match between T-MATS and NPSS at several steady state operating points. Additionally, the T-MATS model extended to run dynamically provides the possibility of simulating and evaluating closed loop responses.

  15. Linking phylogenetic and functional diversity to nutrient spiraling in microbial mats from Lower Kane Cave (USA).

    Science.gov (United States)

    Engel, Annette Summers; Meisinger, Daniela B; Porter, Megan L; Payn, Robert A; Schmid, Michael; Stern, Libby A; Schleifer, K H; Lee, Natuschka M

    2010-01-01

    Microbial mats in sulfidic cave streams offer unique opportunities to study redox-based biogeochemical nutrient cycles. Previous work from Lower Kane Cave, Wyoming, USA, focused on the aerobic portion of microbial mats, dominated by putative chemolithoautotrophic, sulfur-oxidizing groups within the Epsilonproteobacteria and Gammaproteobacteria. To evaluate nutrient cycling and turnover within the whole mat system, a multidisciplinary strategy was used to characterize the anaerobic portion of the mats, including application of the full-cycle rRNA approach, the most probable number method, and geochemical and isotopic analyses. Seventeen major taxonomic bacterial groups and one archaeal group were retrieved from the anaerobic portions of the mats, dominated by Deltaproteobacteria and uncultured members of the Chloroflexi phylum. A nutrient spiraling model was applied to evaluate upstream to downstream changes in microbial diversity based on carbon and sulfur nutrient concentrations. Variability in dissolved sulfide concentrations was attributed to changes in the abundance of sulfide-oxidizing microbial groups and shifts in the occurrence and abundance of sulfate-reducing microbes. Gradients in carbon and sulfur isotopic composition indicated that released and recycled byproduct compounds from upstream microbial activities were incorporated by downstream communities. On the basis of the type of available chemical energy, the variability of nutrient species in a spiraling model may explain observed differences in microbial taxonomic affiliations and metabolic functions, thereby spatially linking microbial diversity to nutrient spiraling in the cave stream ecosystem.

  16. Effects of Elevated Carbon Dioxide and Salinity on the Microbial Diversity in Lithifying Microbial Mats

    Directory of Open Access Journals (Sweden)

    Steven R. Ahrendt

    2014-03-01

    Full Text Available Atmospheric levels of carbon dioxide (CO2 are rising at an accelerated rate resulting in changes in the pH and carbonate chemistry of the world’s oceans. However, there is uncertainty regarding the impact these changing environmental conditions have on carbonate-depositing microbial communities. Here, we examine the effects of elevated CO2, three times that of current atmospheric levels, on the microbial diversity associated with lithifying microbial mats. Lithifying microbial mats are complex ecosystems that facilitate the trapping and binding of sediments, and/or the precipitation of calcium carbonate into organosedimentary structures known as microbialites. To examine the impact of rising CO2 and resulting shifts in pH on lithifying microbial mats, we constructed growth chambers that could continually manipulate and monitor the mat environment. The microbial diversity of the various treatments was compared using 16S rRNA gene pyrosequencing. The results indicated that elevated CO2 levels during the six month exposure did not profoundly alter the microbial diversity, community structure, or carbonate precipitation in the microbial mats; however some key taxa, such as the sulfate-reducing bacteria Deltasulfobacterales, were enriched. These results suggest that some carbonate depositing ecosystems, such as the microbialites, may be more resilient to anthropogenic-induced environmental change than previously thought.

  17. Reefs under Siege—the Rise, Putative Drivers, and Consequences of Benthic Cyanobacterial Mats

    Directory of Open Access Journals (Sweden)

    Amanda K. Ford

    2018-02-01

    Full Text Available Benthic cyanobacteria have commonly been a small but integral component of coral reef ecosystems, fulfilling the critical function of introducing bioavailable nitrogen to an inherently oligotrophic environment. Though surveys may have previously neglected benthic cyanobacteria, or grouped them with more conspicuous benthic groups, emerging evidence strongly indicates that they are becoming increasingly prevalent on reefs worldwide. Some species can form mats comprised by a diverse microbial consortium which allows them to exist across a wide range of environmental conditions. This review evaluates the putative driving factors of increasing benthic cyanobacterial mats, including climate change, declining coastal water quality, iron input, and overexploitation of key consumer and ecosystem engineer species. Ongoing global environmental change can increase growth rates and toxin production of physiologically plastic benthic cyanobacterial mats, placing them at a considerable competitive advantage against reef-building corals. Once established, strong ecological feedbacks [e.g., inhibition of coral recruitment, release of dissolved organic carbon (DOC] reinforce reef degradation. The review also highlights previously overlooked implications of mat proliferation, which can extend beyond reef health and affect human health and welfare. Though identifying (opportunistic consumers of mats remains a priority, their perceived low palatability implies that herbivore management alone may be insufficient to control their proliferation and must be accompanied by local measures to improve water quality and watershed management.

  18. Rapid Reactivation of Cyanobacterial Photosynthesis and Migration upon Rehydration of Desiccated Marine Microbial Mats

    KAUST Repository

    Chennu, Arjun; Grinham, Alistair; Polerecky, Lubos; de Beer, Dirk; Alnajjar, Mohammad Ahmad

    2015-01-01

    Desiccated cyanobacterial mats are the dominant biological feature in the Earth’s arid zones. While the response of desiccated cyanobacteria to rehydration is well-documented for terrestrial systems, information about the response in marine systems is lacking. We used high temporal resolution hyperspectral imaging, liquid chromatography, pulse-amplitude fluorometry, oxygen microsensors, and confocal laser microscopy to study this response in a desiccated microbial mat from Exmouth Gulf, Australia. During the initial 15 min after rehydration chlorophyll a concentrations increased 2–5 fold and cyanobacterial photosynthesis was re-established. Although the mechanism behind this rapid increase of chlorophyll a remains unknown, we hypothesize that it involves resynthesis from a precursor stored in desiccated cyanobacteria. The subsequent phase (15 min–48 h) involved migration of the reactivated cyanobacteria toward the mat surface, which led, together with a gradual increase in chlorophyll a, to a further increase in photosynthesis. We conclude that the response involving an increase in chlorophyll a and recovery of photosynthetic activity within minutes after rehydration is common for cyanobacteria from desiccated mats of both terrestrial and marine origin. However, the response of upward migration and its triggering factor appear to be mat-specific and likely linked to other factors.

  19. Diatom, cyanobacterial and microbial mats as indicators of hydrocarbon contaminated Arctic streams and waters

    Energy Technology Data Exchange (ETDEWEB)

    Ziervogel, H.; Selann, J.; Adeney, B. [EBA Engineering Consultants Ltd., Edmonton, AB (Canada); Nelson, J.A. [J.B. Services, Sarnia, ON (Canada); Murdock, E. [Nunavut Power, Iqaluit (Canada)

    2003-07-01

    An environmental assessment conducted at Repulse Bay, Nunavut in the summer of 2001 revealed a recent diesel spill flowing from the groundwater into a creek. The spill had not been reported. When Arctic surface waters mix with hydrocarbon impacted groundwater and sediments, distinctive mats of diatom, cyanobacteria and other bacteria are formed. These mats have the potential for phytoremediation of hydrocarbons. This paper explained the apparent dominance of mats in contaminated Arctic waters and why they promote biodegradation of hydrocarbons. Hydrocarbon-contaminated soils and groundwater are generally anaerobic. The higher dissolved carbon dioxide in polluted soils and groundwater can benefit photosynthetic cyanobacteria and diatom found in oligotrophic, lower alkalinity Arctic waters. The anaerobic and aerobic bacteria can potentially take advantage of the hydrogen substrate and the nitrogen fixing abilities of the cyanobacteria. Zooplankton predators may be killed off by the toxicity of the polluted groundwater. The paper provides examples where a microbial mat reduced the sulfate content of a hydrocarbon-impacted Arctic stream by 100 ppm, and where a pond covered in a benthic microbial mat showed no evidence of hydrocarbons in the water overlying sediments contaminated with hydrocarbons at concentrations measured at 30,000 ppm. 19 refs., 3 tabs., 8 figs.

  20. Growth, composition and metal removal potential of a Phormidium bigranulatum-dominated mat at elevated levels of cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Dhananjay [Plant Molecular Biology and Plant Physiology Lab, Lab no. 114, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110 067 (India); Yadav, Arpana [Laboratory of Algal Biology, Department of Botany, Banaras Hindu University, Varanasi 221 005 (India); Gaur, J.P., E-mail: gaurjp@yahoo.co.in [Laboratory of Algal Biology, Department of Botany, Banaras Hindu University, Varanasi 221 005 (India)

    2012-07-15

    Prompted by the fact that interaction of metals with cyanobacterial mats has been little studied, the present study evaluates the response of a cyanobacterial mat, dominated by Phormidium bigranulatum, to elevated concentrations of Cd{sup 2+} in the medium. The mat failed to grow at 7 {mu}M of Cd{sup 2+} when the metal as also the mat inoculum were simultaneously added to the medium right in the beginning of the experiment due to marked sensitivity of P. bigranulatum, the main constituent of the mat, to high concentrations of Cd{sup 2+}. However, the mat previously grown in Cd{sup 2+}-free medium for a time period of 1-4 weeks grew successfully when exposed to media containing very high concentrations of Cd{sup 2+}. Four-week-old mat could grow at 250 {mu}M of Cd{sup 2+}, which has been found toxic to many cyanobacteria and algae by previous researchers. Greater tolerance of older mats to Cd{sup 2+} may be due to greater proportion of exopolysaccharides, which are well known to sequester metal ions extracellularly, in them. Whereas the relative proportion of P. bigranulatum declined at high concentrations of the test metal that of green algae increased due most likely to their tolerance to Cd{sup 2+}. Air bubbles were seen entrapped in the mat due obviously to photosynthetic activity. Elevated concentrations of Cd{sup 2+} reduced the number of air bubbles in the mat. Decline in number of air bubbles at high concentrations of metal ions was more prominent in the case of younger mat than in the older one. The present study also evaluated changes in species composition of mats of different age that were subsequently grown in Cd{sup 2+} enriched culture medium. Younger mats showed change in species composition at very low concentrations of Cd{sup 2+}, but older mats showed little changes even at very high concentrations of the test metal. Hence older mats more strongly resisted to changes in its species composition than the younger ones upon exposure to high

  1. Extraction optimization of soluble compounds of yerba maté

    Directory of Open Access Journals (Sweden)

    César Sambiassi

    2002-06-01

    Full Text Available The objective of this research was the extraction optimization of water soluble compounds of yerba maté. Measures variables were extract concentration and weight of leaves and twigs. Controlled variables were time and temperature of extraction and water/solid relation. A surface response method of three variables was used as experimental design, with 20 experiences in each case. The range of each variable, defined in the experimental design, was: extraction time, 13.2 to 46.8 minutes; temperature, 48.2 to 81.8°C and water solid relation, 4.64 to 11.36 g water/100 g of dry solid. Extract weight varied from 13.14 to 29.56 g in leaves and 8.98 to 16.32 g in twigs (each one per 100 g of dry solid. Extract concentration varied between 2.17 and 3.43 g/100 ml in leaves and between 1.32 and 2.31 g/100 ml in twigs. The results were fit to a linear equation in each case.O objetivo desta pesquisa foi a otimização da extração aquosa da erva mate. As variáveis medidas foram a concentração do extrato e a massa das folhas e ramos. As variáveis controladas foram: o tempo e a temperatura de extração e a relação água/sólido. Como desenho experimental foi utilizado o método de resposta superficial de três variáveis, com vinte experiências em cada caso. A faixa de variação definida para as variáveis no desenho experimental foram: tempo de extração, de 13,2 a 46,8 minutos; temperatura, de 48,2 a 81,8 °C; relação água/sólido, de 4,64 a 11,36 gramas de água por gramas de sólido seco. A massa do extrato variou de 13,14 a 29,56 gramas para as folhas desramificadas e de 8,98 a 16,32 para os ramos (cada por 100 gramas de sólido seco. A concentração de extrato variou entre 2,17 a 3,43 g/ 100 ml nas folhas e entre 1,32 e 2,31 g/ 100 ml nos ramos. Os resultados foram, em ambos casos, ajustados para uma equação linear.

  2. Description of electrophoretic loci and tissue specific gene ...

    African Journals Online (AJOL)

    Protein electrophoresis was used to study the distributions and tissue specificity of gene expression of enzymes encoded by 42 loci in Rhinolophus clivosus and R. landeri, the genetically most divergent of the ten species of southern African horseshoe bats. No differences in gene expression were found between R.

  3. Novel loci and pathways significantly associated with longevity

    DEFF Research Database (Denmark)

    Zeng, Yi; Nie, Chao; Min, Junxia

    2016-01-01

    Only two genome-wide significant loci associated with longevity have been identified so far, probably because of insufficient sample sizes of centenarians, whose genomes may harbor genetic variants associated with health and longevity. Here we report a genome-wide association study (GWAS) of Han ...

  4. Novel Associations of Nonstructural Loci with Paraoxonase Activity

    Directory of Open Access Journals (Sweden)

    Ellen E. Quillen

    2012-01-01

    Full Text Available The high-density-lipoprotein-(HDL- associated esterase paraoxonase 1 (PON1 is a likely contributor to the antioxidant and antiatherosclerotic capabilities of HDL. Two nonsynonymous mutations in the structural gene, PON1, have been associated with variation in activity levels, but substantial interindividual differences remain unexplained and are greatest for substrates other than the eponymous paraoxon. PON1 activity levels were measured for three substrates—organophosphate paraoxon, arylester phenyl acetate, and lactone dihydrocoumarin—in 767 Mexican American individuals from San Antonio, Texas. Genetic influences on activity levels for each substrate were evaluated by association with approximately one million single nucleotide polymorphism (SNPs while conditioning on PON1 genotypes. Significant associations were detected at five loci including regions on chromosomes 4 and 17 known to be associated with atherosclerosis and lipoprotein regulation and loci on chromosome 3 that regulate ubiquitous transcription factors. These loci explain 7.8% of variation in PON1 activity with lactone as a substrate, 5.6% with the arylester, and 3.0% with paraoxon. In light of the potential importance of PON1 in preventing cardiovascular disease/events, these novel loci merit further investigation.

  5. Quantitative trait loci (QTL) mapping for inflorescence length traits in ...

    African Journals Online (AJOL)

    Lablab purpureus (L.) sweet is an ancient legume species whose immature pods serve as a vegetable in south and south-east Asia. The objective of this study is to identify quantitative trait loci (QTLs) associated with quantitative traits such as inflorescence length, peduncle length from branch to axil, peduncle length from ...

  6. Molecular and genetic analyses of potato cyst nematode resistance loci

    NARCIS (Netherlands)

    Bakker, E.H.

    2003-01-01

    This thesis describes the genomic localisation and organisation of loci that harbour resistance to the potato cyst nematode species Globodera pallida and G. rostochiensis . Resistance to the potato cyst nematodes G. pallida and G. rostochiensis is an important aspect in potato breeding. To gain

  7. Quantitative Trait Loci Affecting Calving Traits in Danish Holstein Cattle

    DEFF Research Database (Denmark)

    Thomasen, J R; Guldbrandtsen, B; Sørensen, P

    2008-01-01

    The objectives of this study were 1) to detect quantitative trait loci (QTL) affecting direct and maternal calving traits at first calving in the Danish Holstein population, 2) to distinguish between pleiotropic and linked QTL for chromosome regions affecting more than one trait, and 3) to detect...

  8. Allele frequency distribution for 21 autosomal STR loci in Bhutan.

    Science.gov (United States)

    Kraaijenbrink, Thirsa; van Driem, George L; Tshering of Gaselô, Karma; de Knijff, Peter

    2007-07-20

    We studied the allele frequency distribution of 21 autosomal STR loci contained in the AmpFlSTR Identifiler (Applied Biosystems), the Powerplex 16 (Promega) and the FFFL (Promega) multiplex PCR kits among 936 individuals from the Royal Kingdom of Bhutan. As such these are the first published autosomal DNA results from this country.

  9. Cross-genus amplification and characterisation of microsatellite loci ...

    African Journals Online (AJOL)

    Jennifer Lamb

    Unknown. RESULTS AND DISCUSSION. Three of the nine loci initially tested were discarded, as it was either not possible to amplify them across all sam- ples, or because the banding pattern was too ambiguous to score. The data were checked for errors in scoring due to stuttering, large allele dropout or null alleles using.

  10. Testing independence of fragment lengths within VNTR loci

    Energy Technology Data Exchange (ETDEWEB)

    Geisser, S. (Univ. of Minnesota, Minneapolis, MN (United States)); Johnson, W. (Univ. of California, Davis, CA (United States))

    1993-11-01

    Methods that were devised to test independence of the bivariate fragment lengths obtained from VNTR loci are applied to several population databases. It is shown that for many of the probes independence (Hardy-Weinberg equilibrium) cannot be sustained. 3 refs., 3 tabs.

  11. Quantitative trait loci associated with anthracnose resistance in sorghum

    Science.gov (United States)

    With an aim to develop a durable resistance to the fungal disease anthracnose, two unique genetic sources of resistance were selected to create genetic mapping populations to identify regions of the sorghum genome that encode anthracnose resistance. A series of quantitative trait loci were identifi...

  12. Blood Pressure Loci Identified with a Gene-Centric Array

    NARCIS (Netherlands)

    Johnson, Toby; Gaunt, Tom R.; Newhouse, Stephen J.; Padmanabhan, Sandosh; Tomaszewski, Maciej; Kumari, Meena; Morris, Richard W.; Tzoulaki, Ioanna; O'Brien, Eoin T.; Poulter, Neil R.; Sever, Peter; Shields, Denis C.; Thom, Simon; Wannamethee, Sasiwarang G.; Whincup, Peter H.; Brown, Morris J.; Connell, John M.; Dobson, Richard J.; Howard, Philip J.; Mein, Charles A.; Onipinla, Abiodun; Shaw-Hawkins, Sue; Zhang, Yun; Smith, George Davey; Day, Ian N. M.; Lawlor, Debbie A.; Goodall, Alison H.; Fowkes, F. Gerald; Abecasis, Goncalo R.; Elliott, Paul; Gateva, Vesela; Braund, Peter S.; Burton, Paul R.; Nelson, Christopher P.; Tobin, Martin D.; van der Harst, Pim; Glorioso, Nicola; Neuvrith, Hani; Salvi, Erika; Staessen, Jan A.; Stucchi, Andrea; Devos, Nabila; Jeunemaitre, Xavier; Plouin, Pierre-Francois; Tichet, Jean; Juhanson, Peeter; Org, Elin; Westra, Harm-Jan; Wolfs, Marcel G. M.; Franke, Lude

    2011-01-01

    Raised blood pressure (BP) is a major risk factor for cardiovascular disease. Previous studies have identified 47 distinct genetic variants robustly associated with BP, but collectively these explain only a few percent of the heritability for BP phenotypes. To find additional BP loci, we used a

  13. Quantitative trait loci for behavioural traits in chicken

    NARCIS (Netherlands)

    Buitenhuis, A.J.; Rodenburg, T.B.; Siwek, M.Z.; Cornelissen, S.J.B.; Nieuwland, M.G.B.; Crooijmans, R.P.M.A.; Groenen, M.A.M.; Koene, P.; Bovenhuis, H.; Poel, van der J.J.

    2005-01-01

    The detection of quantitative trait loci (QTL) of behavioural traits has mainly been focussed on mouse and rat. With the rapid development of molecular genetics and the statistical tools, QTL mapping for behavioural traits in farm animals is developing. In chicken, a total of 30 QTL involved in

  14. Supplementary data: Mapping of shoot fly tolerance loci in sorghum ...

    Indian Academy of Sciences (India)

    Supplementary data: Mapping of shoot fly tolerance loci in sorghum using SSR markers. D. B. Apotikar, D. Venkateswarlu, R. B. Ghorade, R. M. Wadaskar, J. V. Patil and P. L. Kulwal. J. Genet. 90, 59–66. Table 1. List of SSR primers for sorghum. Primer code. Forward and reverse. Annealing temperature (°C). Product.

  15. Biological insights from 108 schizophrenia-associated genetic loci

    DEFF Research Database (Denmark)

    Ripke, Stephan; Neale, Benjamin M.; Corvin, Aiden

    2014-01-01

    and 113,075 controls. We identify 128 independent associations spanning 108 conservatively defined loci that meet genome-wide significance, 83 of which have not been previously reported. Associations were enriched among genes expressed in brain, providing biological plausibility for the findings. Many...

  16. Determination of allele frequencies in nine short tandem repeat loci ...

    African Journals Online (AJOL)

    SERVER

    2008-04-17

    Apr 17, 2008 ... out the human genome. These loci are a rich source of highly polymorphic markers that may be detected using the polymerase chain reaction (PCR). PCR is a mimic of the normal cellular process of replication of DNA molecules. Each STR is distinguished by the number of times a sequence is repeated, ...

  17. Chromosomal localization of microsatellite loci in Drosophila mediopunctata

    Directory of Open Access Journals (Sweden)

    Renato Cavasini

    2015-03-01

    Full Text Available Drosophila mediopunctata has been used as a model organism for genetics and evolutionary studies in the last three decades. A linkage map with 48 microsatellite loci recently published for this species showed five syntenic groups, which had their homology determined to Drosophila melanogaster chromosomes. Then, by inference, each of the groups was associated with one of the five major chromosomes of D. mediopunctata. Our objective was to carry out a genetic (chromosomal analysis to increase the number of available loci with known chromosomal location. We made a simultaneous analysis of visible mutant phenotypes and microsatellite genotypes in a backcross of a standard strain and a mutant strain, which had each major autosome marked. Hence, we could establish the chromosomal location of seventeen loci; including one from each of the five major linkage groups previously published, and twelve new loci. Our results were congruent with the previous location and they open new possibilities to future work integrating microsatellites, chromosomal inversions, and genetic determinants of physiological and morphological variation.

  18. Development of polymorphic microsatellite loci for the tomato leaf ...

    Indian Academy of Sciences (India)

    lite loci for the tomato leaf miner, Tuta absoluta (Lepidoptera: Gelechiidae). J. Genet. 92, e110–e112. Online only ... idae) is a devastating pest of tomato originating from South. America (García and Espul 1982). .... ture of Aphis spiraecola (Hemiptera: Aphididae) on pear trees in. China identified using microsatellites.

  19. A Matérn model of the spatial covariance structure of point rain rates

    KAUST Repository

    Sun, Ying

    2014-07-15

    It is challenging to model a precipitation field due to its intermittent and highly scale-dependent nature. Many models of point rain rates or areal rainfall observations have been proposed and studied for different time scales. Among them, the spectral model based on a stochastic dynamical equation for the instantaneous point rain rate field is attractive, since it naturally leads to a consistent space–time model. In this paper, we note that the spatial covariance structure of the spectral model is equivalent to the well-known Matérn covariance model. Using high-quality rain gauge data, we estimate the parameters of the Matérn model for different time scales and demonstrate that the Matérn model is superior to an exponential model, particularly at short time scales.

  20. A Matérn model of the spatial covariance structure of point rain rates

    KAUST Repository

    Sun, Ying; Bowman, Kenneth P.; Genton, Marc G.; Tokay, Ali

    2014-01-01

    It is challenging to model a precipitation field due to its intermittent and highly scale-dependent nature. Many models of point rain rates or areal rainfall observations have been proposed and studied for different time scales. Among them, the spectral model based on a stochastic dynamical equation for the instantaneous point rain rate field is attractive, since it naturally leads to a consistent space–time model. In this paper, we note that the spatial covariance structure of the spectral model is equivalent to the well-known Matérn covariance model. Using high-quality rain gauge data, we estimate the parameters of the Matérn model for different time scales and demonstrate that the Matérn model is superior to an exponential model, particularly at short time scales.

  1. Chapitre 4. Matériaux de construction et de décoration

    OpenAIRE

    Harlé-Sambet, Yvonne; Cabart, Hubert; Charmoillaux, Julie; Girard, Ghislaine

    2017-01-01

    Si la brique apparaît comme le matériau le plus utilisé lors de la construction du château, on est cependant frappé par la variété des autres matériaux mis en œuvre. Les murs les plus anciens du logis est (XIIe siècle) ainsi que les fondations et le soubassement du château de brique (fin XIIIe siècle) sont constitués de maçonneries de galets liés au mortier. Le galet est en effet le matériau le plus fréquemment utilisé à toutes les époques dans les constructions du bas-Dauphiné. Cependant à B...

  2. Millimeter Wavelength Observations of Galactic Sources with the Mobile Anisotropy Telescope (MAT)

    Science.gov (United States)

    Cruz, K. L.; Caldwell, R.; Devlin, M. J.; Dorwart, W. B.; Herbig, T.; Miller, A. D.; Nolta, M. R.; Page, L. A.; Puchalla, J. L.; Torbet, E.; Tran, H. T.

    1999-12-01

    The Mobile Anisotropy Telescope (MAT) has completed two observing seasons (1997 and 1998) in Chile from the Cerro Toco site. Although the primary goal of MAT was to measure anisotropy in the Cosmic Microwave Background (CMB) radiation, the chosen observation scheme also allowed daily viewing of the Galactic Plane. We present filtered maps at 30, 40 and 144 GHz of a region of the Galactic Plane which contains several millimeter-bright regions including the Carinae nebula and IRAS 11097-6102. We report the best fit brightness temperatures as well as the total flux densities in the MAT beams (0.9, 0.6 and 0.2 degrees FWHM) . The data are calibrated with respect to Jupiter whose flux is known to better than 8% in all frequency bands. This work was funded by the National Science Foundation and the Packard Foundation.

  3. Gro2mat: a package to efficiently read gromacs output in MATLAB.

    Science.gov (United States)

    Dien, Hung; Deane, Charlotte M; Knapp, Bernhard

    2014-07-30

    Molecular dynamics (MD) simulations are a state-of-the-art computational method used to investigate molecular interactions at atomic scale. Interaction processes out of experimental reach can be monitored using MD software, such as Gromacs. Here, we present the gro2mat package that allows fast and easy access to Gromacs output files from Matlab. Gro2mat enables direct parsing of the most common Gromacs output formats including the binary xtc-format. No openly available Matlab parser currently exists for this format. The xtc reader is orders of magnitudes faster than other available pdb/ascii workarounds. Gro2mat is especially useful for scientists with an interest in quick prototyping of new mathematical and statistical approaches for Gromacs trajectory analyses. © 2014 Wiley Periodicals, Inc. Copyright © 2014 Wiley Periodicals, Inc.

  4. Does the evolutionary conservation of microsatellite loci imply function?

    Energy Technology Data Exchange (ETDEWEB)

    Shriver, M.D.; Deka, R.; Ferrell, R.E. [Univ. of Pittsburgh, PA (United States)] [and others

    1994-09-01

    Microsatellites are highly polymorphic tandem arrays of short (1-6 bp) sequence motifs which have been found widely distributed in the genomes of all eukaryotes. We have analyzed allele frequency data on 16 microsatellite loci typed in the great apes (human, chimp, orangutan, and gorilla). The majority of these loci (13) were isolated from human genomic libraries; three were cloned from chimpanzee genomic DNA. Most of these loci are not only present in all apes species, but are polymorphic with comparable levels of heterozygosity and have alleles which overlap in size. The extent of divergence of allele frequencies among these four species were studies using the stepwise-weighted genetic distance (Dsw), which was previously shown to conform to linearity with evolutionary time since divergence for loci where mutations exist in a stepwise fashion. The phylogenetic tree of the great apes constructed from this distance matrix was consistent with the expected topology, with a high bootstrap confidence (82%) for the human/chimp clade. However, the allele frequency distributions of these species are 10 times more similar to each other than expected when they were calibrated with a conservative estimate of the time since separation of humans and the apes. These results are in agreement with sequence-based surveys of microsatellites which have demonstrated that they are highly (90%) conserved over short periods of evolutionary time (< 10 million years) and moderately (30%) conserved over long periods of evolutionary time (> 60-80 million years). This evolutionary conservation has prompted some authors to speculate that there are functional constraints on microsatellite loci. In contrast, the presence of directional bias of mutations with constraints and/or selection against aberrant sized alleles can explain these results.

  5. Origins of amino acid transporter loci in trypanosomatid parasites

    Directory of Open Access Journals (Sweden)

    Jackson Andrew P

    2007-02-01

    Full Text Available Abstract Background Large amino acid transporter gene families were identified from the genome sequences of three parasitic protists, Trypanosoma brucei, Trypanosoma cruzi and Leishmania major. These genes encode molecular sensors of the external host environment for trypanosomatid cells and are crucial to modulation of gene expression as the parasite passes through different life stages. This study provides a comprehensive phylogenetic account of the origins of these genes, redefining each locus according to a positional criterion, through the integration of phyletic identity with comparative gene order information. Results Each locus was individually specified by its surrounding gene order and associated with homologs showing the same position ('homoeologs' in other species, where available. Bayesian and maximum likelihood phylogenies were in general agreement on systematic relationships and confirmed several 'orthology sets' of genes retained since divergence from the common ancestor. Reconciliation analysis quantified the scale of duplication and gene loss, as well as identifying further apparent orthology sets, which lacked conservation of genomic position. These instances suggested substantial genomic restructuring or transposition. Other analyses identified clear instances of evolutionary rate changes post-duplication, the effects of concerted evolution within tandem gene arrays and gene conversion events between syntenic loci. Conclusion Despite their importance to cell function and parasite development, the repertoires of AAT loci in trypanosomatid parasites are relatively fluid in both complement and gene dosage. Some loci are ubiquitous and, after an ancient origin through transposition, originated through descent from the ancestral trypanosomatid. However, reconciliation analysis demonstrated that unilateral expansions of gene number through tandem gene duplication, transposition of gene duplicates to otherwise well conserved genomic

  6. Spatial patterns and links between microbial community composition and function in cyanobacterial mats

    KAUST Repository

    Alnajjar, Mohammad Ahmad; Ramette, Alban; Kü hl, Michael; Hamza, Waleed; Klatt, Judith M.; Polerecky, Lubos

    2014-01-01

    We imaged reflectance and variable fluorescence in 25 cyanobacterial mats from four distant sites around the globe to assess, at different scales of resolution, spatial variabilities in the physiological parameters characterizing their photosynthetic capacity, including the absorptivity by chlorophyll a (Achl), maximum quantum yield of photosynthesis (Ymax), and light acclimation irradiance (Ik). Generally, these parameters significantly varied within individual mats on a sub-millimeter scale, with about 2-fold higher variability in the vertical than in the horizontal direction. The average vertical profiles of Ymax and Ik decreased with depth in the mat, while Achl exhibited a sub-surface maximum. The within-mat variability was comparable to, but often larger than, the between-sites variability, whereas the within-site variabilities (i.e., between samples from the same site) were generally lowest. When compared based on averaged values of their photosynthetic parameters, mats clustered according to their site of origin. Similar clustering was found when the community composition of the mats' cyanobacterial layers were compared by automated ribosomal intergenic spacer analysis (ARISA), indicating a significant link between the microbial community composition and function. Although this link is likely the result of community adaptation to the prevailing site-specific environmental conditions, our present data is insufficient to identify the main factors determining these patterns. Nevertheless, this study demonstrates that the spatial variability in the photosynthetic capacity and light acclimation of benthic phototrophic microbial communities is at least as large on a sub-millimeter scale as it is on a global scale, and suggests that this pattern of variability scaling is similar for the microbial community composition. © 2014 Al-Najjar, Ramette, Kühl, Hamza, Klatt and Polerecky.

  7. Anti-fatigue mats, low back pain, and electromyography: An interventional study.

    Science.gov (United States)

    Aghazadeh, Javad; Ghaderi, Mahmoud; Azghani, Mahmood-Reza; Khalkhali, Hamid-Reza; Allahyari, Teimour; Mohebbi, Iraj

    2015-01-01

    Increasing bilateral gluteus medius co-activation has been identified as one of the most important factors in developing low back pain due to prolonged standing in healthy people. This study aims to investigate the impact of an anti-fatigue mat on the bilateral gluteus medius co-activation pattern and to report the low back pain subjectively in 2 different standing positions on the normal rigid surface and on the anti-fatigue mat. While carrying out an easy simulated profession, 16 participants who had no low back pain background were requested to stand for 2 h in each position, with and without using the anti-fatigue floor mat, respectively. At the beginning of standing process and at every 15 min until the time of 120 min lapses, electric activities for the bilateral gluteus medius co-activation and subjective pain level in low back area were collected by the surface electromyogeraphy (EMG) and the visual analogue scale (VAS), respectively in each position. The obtained findings revealed that the anti-fatigue mat significantly decreased subjective pain level in low back area among 15 participants (p 0.05). The findings obtained under this study related to the impact of the anti-fatigue mat upon the low back pain based on the increase of > 10 mm on the VAS threshold, which showed that this intervention had no significant impact upon decreasing the number of patients suffering from the low back pain and also minimizing the bilateral gluteus medius co-activation in both pain developer groups (p > 0.05). However, 73% of the participants preferred to apply it. It seems that the anti-fatigue mat may be useful in reducing the low back pain although it objectively didn't significantly change the gluteus medius co-activation pattern related to the low back pain. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  8. Spatial patterns and links between microbial community composition and function in cyanobacterial mats

    KAUST Repository

    Alnajjar, Mohammad Ahmad

    2014-08-06

    We imaged reflectance and variable fluorescence in 25 cyanobacterial mats from four distant sites around the globe to assess, at different scales of resolution, spatial variabilities in the physiological parameters characterizing their photosynthetic capacity, including the absorptivity by chlorophyll a (Achl), maximum quantum yield of photosynthesis (Ymax), and light acclimation irradiance (Ik). Generally, these parameters significantly varied within individual mats on a sub-millimeter scale, with about 2-fold higher variability in the vertical than in the horizontal direction. The average vertical profiles of Ymax and Ik decreased with depth in the mat, while Achl exhibited a sub-surface maximum. The within-mat variability was comparable to, but often larger than, the between-sites variability, whereas the within-site variabilities (i.e., between samples from the same site) were generally lowest. When compared based on averaged values of their photosynthetic parameters, mats clustered according to their site of origin. Similar clustering was found when the community composition of the mats\\' cyanobacterial layers were compared by automated ribosomal intergenic spacer analysis (ARISA), indicating a significant link between the microbial community composition and function. Although this link is likely the result of community adaptation to the prevailing site-specific environmental conditions, our present data is insufficient to identify the main factors determining these patterns. Nevertheless, this study demonstrates that the spatial variability in the photosynthetic capacity and light acclimation of benthic phototrophic microbial communities is at least as large on a sub-millimeter scale as it is on a global scale, and suggests that this pattern of variability scaling is similar for the microbial community composition. © 2014 Al-Najjar, Ramette, Kühl, Hamza, Klatt and Polerecky.

  9. "Byrummets ånd. Genius Loci/The Spirit of Urban Spaces"

    DEFF Research Database (Denmark)

    Reeh, Henrik

    2004-01-01

    byrum, Genius loci, Christian Norberg-Schulz, Sønder Boulevard, Berlin, nykultur, fortove, barndomserindringer......byrum, Genius loci, Christian Norberg-Schulz, Sønder Boulevard, Berlin, nykultur, fortove, barndomserindringer...

  10. Association analyses of 249,796 individuals reveal 18 new loci associated with body mass index

    DEFF Research Database (Denmark)

    Speliotes, Elizabeth K; Willer, Cristen J; Berndt, Sonja I

    2010-01-01

    in up to 125,931 additional individuals. We confirmed 14 known obesity susceptibility loci and identified 18 new loci associated with body mass index (P SH2B1 and BDNF) map near key hypothalamic regulators...

  11. [A population genetic study of 22 autosomal loci of single nucleotide polymorphisms].

    Science.gov (United States)

    Tang, Jian-pin; Jiang, Feng-hui; Shi, Mei-sen; Xu, Chuan-chao; Chen, Rui; Lai, Xiao-pin

    2012-12-01

    To evaluate polymorphisms and forensic efficiency of 22 non-binary single nucleotide polymorphism (SNP) loci. One hundred ethnic Han Chinese individuals were recruited from Dongguan, Guangdong. The 22 loci were genotyped with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). Nine loci were found with a single allele, 4 loci were found to be biallelic, whilst 9 loci were found to have 3 alleles. For 13 polymorphic loci, the combined discrimination power and power of exclusion were 0.999 98 and 0.9330, respectively. For the 9 non-biallelic loci, the combined discrimination power and power of exclusion were 0.9998 and 0.8956, respectively. For motherless cases, the combined power of exclusion was 0.6405 for 13 polymorphic SNPs and 0.6405 for 9 non-binary SNPs. Non-binary loci have a greater discrimination power and exclusion power per SNP.

  12. Genes and quality trait loci (QTLs) associated with firmness in Malus x domestica

    KAUST Repository

    Marondedze, Claudius; Thomas, Ludivine

    2013-01-01

    , crunchiness and crispness. Fruit firmness is affected by the inheritance of alleles at multiple loci and their possible interactions with the environment. Identification of these loci is key for the determination of genetic candidate markers that can

  13. Modular development mat reinforcing and liners containment/annulus building. Final report supplement. Volume I

    International Nuclear Information System (INIS)

    Wainrib, J.

    1978-06-01

    The feasibility of developing a modular system approach for the construction of containment mats has been established. The investigative results obtained from a plant used for the modular study has determined that (1) modularization results in a 10-week reduction in the construction schedule critical path over that for the conventional approach, and (2) modularization is cost effective and could result in a savings of approximately $10,700,000. Accordingly, it is recommended that the modular system approach be adopted as standard practice for the construction of containment mats

  14. The effect Mat Pilates practice on muscle mass in elderly women

    Directory of Open Access Journals (Sweden)

    Leliz Cristina Sampaio Queiroz

    2016-01-01

    Full Text Available Objective: to verify that the Mat Pilates practice increases muscle mass in elderly women. Methods: quasi-experimental study with primary data collection and with a convenience sample. The muscle mass of 43 elderly was evaluated for 11 weeks, by calculating the arm muscle area, before and after the intervention. Results:statistically significant difference was observed (p<0.002 between the average value of the arm muscle area, before (35.56cm2 and after the exercises (42.72cm2. Conclusion: mat Pilates program generates positive effect on increasing the muscle mass of elderly.

  15. MAT-DB - A database for nuclear energy related materials data

    International Nuclear Information System (INIS)

    Over, H.H.

    2009-01-01

    The web-enabled materials database (Mat-DB) of JRC-IE has a long-term history in storing materials test data resulting from European and international research projects. The database structure and the user-guidance has bee permanently updated improved and optimized. The database is implemented in the secure ODIN portal: https://odin.jrc.ec.europa.eu of JRC-IE. This architecture guarantees fast access to confidential and public data and documentation which are stored in an inter-related document management database (DoMa). It is a part of JRC's nuclear knowledge management. Mat-DB hosts the whole pool of IAEA surveillance data of reactor pressure vessel materials from different nuclear power plants of the member states. Mat-DB contains also thousands of European GEN IV reactor systems related R and D materials data which are an important basis for the evaluating and extrapolating design data for candidate materials and setting up design rules covering high temperature exposure, irradiation and corrosion. Those data and rules would match also fusion related components. Mat-DB covers thermo-mechanical and thermo-physical properties data of engineering alloys at low, elevated and high temperatures for base materials and joints, including irradiated materials for nuclear fission and fusion applications, thermal barrier coated materials for gas turbines and properties of corroded materials. The corrosion part refers to weight gain/loss data of high temperature exposed engineering alloys and ceramic materials. For each test type the database structure reflects international test standards and recommendations. Mat-DB features an extensive library of evaluation programs for web-enabled assessment of uniaxial creep, fatigue, crack growth and high temperature corrosion properties. Evaluations can be performed after data retrieval or independently of Mat-DB by transferring other materials data in a given format to the programs. The fast evaluation processes help the user to

  16. MatMCNP: A Code for Producing Material Cards for MCNP

    Energy Technology Data Exchange (ETDEWEB)

    DePriest, Kendall Russell [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Saavedra, Karen C. [American Structurepoint, Inc., Indianapolis, IN (United States)

    2014-09-01

    A code for generating MCNP material cards (MatMCNP) has been written and verified for naturally occurring, stable isotopes. The program allows for material specification as either atomic or weight percent (fractions). MatMCNP also permits the specification of enriched lithium, boron, and/or uranium. In addition to producing the material cards for MCNP, the code calculates the atomic (or number) density in atoms/barn-cm as well as the multiplier that should be used to convert neutron and gamma fluences into dose in the material specified.

  17. Bagging system, soil stabilization mat, and tent frame for a lunar base

    Science.gov (United States)

    1990-01-01

    Georgia Tech's School of Textile and Fiber Engineering and School of Mechanical Engineering participated in four cooperative design efforts this year. Each of two interdisciplinary teams designed a system consisting of a lunar regolith bag and an apparatus for filling this bag. The third group designed a mat for stabilization of lunar soil during takeoff and landing, and a method for packaging and deploying this mat. Finally, the fourth group designed a sunlight diffusing tent to be used as a lunar worksite. Summaries of these projects are given.

  18. Contradicción, coherencia y compromiso: Matías Usero Torrente

    Directory of Open Access Journals (Sweden)

    Tezanos Gandarillas, Marisa

    2001-06-01

    Full Text Available The current article studies the figure of Matías Usero Torrente. His thought is considered by the author as a preceding of the principals ideas that emphasized about the relations between State and Society during the sixties in Spain.

    En el presente artículo se analiza la figura de Matías Usero Torrente. Su pensamiento es considerado por la autora del estudio como antecesor de las principales ideas que sobre las relaciones de la Iglesia con el Estado y la Sociedad cristalizaron en la década de los 60 en España.

  19. Interaction of gelatin with polyenes modulates antifungal activity and biocompatibility of electrospun fiber mats

    Directory of Open Access Journals (Sweden)

    Lakshminarayanan R

    2014-05-01

    Full Text Available Rajamani Lakshminarayanan,1,2 Radhakrishnan Sridhar,3,4 Xian Jun Loh,5 Muruganantham Nandhakumar,1 Veluchamy Amutha Barathi,1,6 Madhaiyan Kalaipriya,3,4 Jia Lin Kwan,1 Shou Ping Liu,1,2 Roger Wilmer Beuerman,1,2 Seeram Ramakrishna3,4,7 1Singapore Eye Research Institute, 2Signature Research Program in Neuroscience and Behavioral Disorders, Duke-NUS Graduate Medical School, 3Department of Mechanical Engineering, National University of Singapore, 4Center for Nanofibers and Nanotechnology, National University of Singapore, 5Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research, 3 Research Link, Singapore, 6Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, 7NUS Nanoscience and Nanotechnology Initiative, Singapore Abstract: Topical application of antifungals does not have predictable or well-controlled release characteristics and requires reapplication to achieve therapeutic local concentration in a reasonable time period. In this article, the efficacy of five different US Food and Drug Administration-approved antifungal-loaded (amphotericin B, natamycin, terbinafine, fluconazole, and itraconazole electrospun gelatin fiber mats were compared. Morphological studies show that incorporation of polyenes resulted in a two-fold increase in fiber diameter and the mats inhibit the growth of yeasts and filamentous fungal pathogens. Terbinafine-loaded mats were effective against three filamentous fungal species. Among the two azole antifungals compared, the itraconazole-loaded mat was potent against Aspergillus strains. However, activity loss was observed for fluconazole-loaded mats against all of the test organisms. The polyene-loaded mats displayed rapid candidacidal activities as well. Biophysical and rheological measurements indicate strong interactions between polyene antifungals and gelatin matrix. As a result, the polyenes stabilized the triple helical

  20. Microbial Diversity and Lipid Abundance in Microbial Mats from a Sulfidic, Saline, Warm Spring in Utah, USA

    Science.gov (United States)

    Gong, J.; Edwardson, C.; Mackey, T. J.; Dzaugis, M.; Ibarra, Y.; Course 2012, G.; Frantz, C. M.; Osburn, M. R.; Hirst, M.; Williamson, C.; Hanselmann, K.; Caporaso, J.; Sessions, A. L.; Spear, J. R.

    2012-12-01

    The microbial diversity of Stinking Springs, a sulfidic, saline, warm spring northeast of the Great Salt Lake was investigated. The measured pH, temperature, salinity, and sulfide concentration along the flow path ranged from 6.64-7.77, 40-28° C, 2.9-2.2%, and 250 μM to negligible, respectively. Five sites were selected along the flow path and within each site microbial mats were dissected into depth profiles based on the color and texture of the mat layers. Genomic DNA was extracted from each layer, and the 16S rRNA gene was amplified and sequenced on the Roche 454 Titanium platform. Fatty acids were also extracted from the mat layers and analyzed by liquid chromatography and mass spectrometry. The mats at Stinking Springs were classified into roughly two morphologies with respect to their spatial distribution: loose, sometimes floating mats proximal to the spring source; and thicker, well-laminated mats distal to the spring source. Loosely-laminated mats were found in turbulent stream flow environments, whereas well-laminated mats were common in less turbulent sheet flows. Phototrophs, sulfur oxidizers, sulfate reducers, methanogens, other bacteria and archaea were identified by 16S rRNA gene sequences. Diatoms, identified by microscopy and lipid analysis were found to increase in abundance with distance from the source. Methanogens were generally more abundant in deeper mat laminae. Photoheterotrophs were found in all mat layers. Microbial diversity increased significantly with depth at most sites. In addition, two distinct microbial streamers were identified and characterized at the two fast flowing sites. These two streamer varieties were dominated by either cyanobacteria or flavobacteria. Overall, our genomic and lipid analysis suggest that the physical and chemical environment is more predictive of the community composition than mat morphology. Site Map

  1. rMATS: robust and flexible detection of differential alternative splicing from replicate RNA-Seq data.

    Science.gov (United States)

    Shen, Shihao; Park, Juw Won; Lu, Zhi-xiang; Lin, Lan; Henry, Michael D; Wu, Ying Nian; Zhou, Qing; Xing, Yi

    2014-12-23

    Ultra-deep RNA sequencing (RNA-Seq) has become a powerful approach for genome-wide analysis of pre-mRNA alternative splicing. We previously developed multivariate analysis of transcript splicing (MATS), a statistical method for detecting differential alternative splicing between two RNA-Seq samples. Here we describe a new statistical model and computer program, replicate MATS (rMATS), designed for detection of differential alternative splicing from replicate RNA-Seq data. rMATS uses a hierarchical model to simultaneously account for sampling uncertainty in individual replicates and variability among replicates. In addition to the analysis of unpaired replicates, rMATS also includes a model specifically designed for paired replicates between sample groups. The hypothesis-testing framework of rMATS is flexible and can assess the statistical significance over any user-defined magnitude of splicing change. The performance of rMATS is evaluated by the analysis of simulated and real RNA-Seq data. rMATS outperformed two existing methods for replicate RNA-Seq data in all simulation settings, and RT-PCR yielded a high validation rate (94%) in an RNA-Seq dataset of prostate cancer cell lines. Our data also provide guiding principles for designing RNA-Seq studies of alternative splicing. We demonstrate that it is essential to incorporate biological replicates in the study design. Of note, pooling RNAs or merging RNA-Seq data from multiple replicates is not an effective approach to account for variability, and the result is particularly sensitive to outliers. The rMATS source code is freely available at rnaseq-mats.sourceforge.net/. As the popularity of RNA-Seq continues to grow, we expect rMATS will be useful for studies of alternative splicing in diverse RNA-Seq projects.

  2. Isolation and characterization of microsatellite loci from the Australasian sea snake, Aipysurus laevis

    DEFF Research Database (Denmark)

    Lukoschek, Vimoksalehi; Waycott, Michelle; Dunshea, Glenn

    2005-01-01

    We developed 13 microsatellite loci for the olive sea snake, Aipysurus laevis, using both enriched and unenriched genomic DNA libraries. Eleven codominant loci, that reliably amplified, were used to screen 32 individuals across the geographic range of A. laevis. Four loci had four or more alleles...... (maximum 12), whereas the other seven had either two or three. All but one locus was in Hardy-Weinberg equilibrium. These loci will provide useful markers to investigate population genetic structure for the olive sea snake....

  3. Identification of four novel susceptibility loci for oestrogen receptor negative breast cancer

    DEFF Research Database (Denmark)

    Couch, Fergus J; Kuchenbaecker, Karoline B; Michailidou, Kyriaki

    2016-01-01

    Common variants in 94 loci have been associated with breast cancer including 15 loci with genome-wide significant associations (P<5 × 10(-8)) with oestrogen receptor (ER)-negative breast cancer and BRCA1-associated breast cancer risk. In this study, to identify new ER-negative susceptibility loci...

  4. Multi-ethnic fine-mapping of 14 central adiposity loci

    NARCIS (Netherlands)

    Liu, C.T.; Buchkovich, M.L.; Winkler, T.W.; Heid, I.M.; Hottenga, J.J.; Boomsma, D.I.; de Geus, E.J.C.; Willemsen, G.; Borecki, I.B.; Fox, C.S.; Mohlke, K.L.; North, K.E.; Cupples, L.A.

    2014-01-01

    The Genetic Investigation of Anthropometric Traits (GIANT) consortium identified 14 loci in European Ancestry (EA) individuals associated with waist-to-hip ratio (WHR) adjusted for body mass index. These loci are wide and narrowingthe signalsremains necessary. Twelve of 14 loci identified inGIANTEA

  5. Identification of four novel susceptibility loci for oestrogen receptor negative breast cancer

    NARCIS (Netherlands)

    Couch, Fergus J; Kuchenbaecker, Karoline B; Michailidou, Kyriaki; Mendoza-Fandino, Gustavo A; Nord, Silje; Lilyquist, Janna; Olswold, Curtis; Hallberg, Emily; Agata, Simona; Ahsan, Habibul; Aittomäki, Kristiina; Ambrosone, Christine; Andrulis, Irene L; Anton-Culver, Hoda; Arndt, Volker; Arun, Banu K; Arver, Brita; Barile, Monica; Barkardottir, Rosa B; Barrowdale, Daniel; Beckmann, Lars; Beckmann, Matthias W; Benitez, Javier; Blank, Stephanie V; Blomqvist, Carl; Bogdanova, Natalia V; Bojesen, Stig E; Bolla, Manjeet K; Bonanni, Bernardo; Brauch, Hiltrud; Brenner, Hermann; Burwinkel, Barbara; Buys, Saundra S; Caldes, Trinidad; Caligo, Maria A; Canzian, Federico; Carpenter, Jane; Chang-Claude, Jenny; Chanock, Stephen J; Chung, Wendy K; Claes, Kathleen B M; Cox, Angela; Cross, Simon S; Cunningham, Julie M; Czene, Kamila; Daly, Mary B; Damiola, Francesca; Darabi, Hatef; de la Hoya, Miguel; Devilee, Peter; Diez, Orland; Ding, Yuan C; Dolcetti, Riccardo; Domchek, Susan M; Dorfling, Cecilia M; Dos-Santos-Silva, Isabel; Dumont, Martine; Dunning, Alison M; Eccles, Diana M; Ehrencrona, Hans; Ekici, Arif B; Eliassen, Heather; Ellis, Steve; Fasching, Peter A; Figueroa, Jonine; Flesch-Janys, Dieter; Försti, Asta; Fostira, Florentia; Foulkes, William D; Friebel, Tara; Friedman, Eitan; Frost, Debra; Gabrielson, Marike; Gammon, Marilie D; Ganz, Patricia A; Gapstur, Susan M; Garber, Judy; Gaudet, Mia M; Gayther, Simon A; Gerdes, Anne-Marie; Ghoussaini, Maya; Giles, Graham G; Glendon, Gord; Godwin, Andrew K; Goldberg, Mark S; Goldgar, David E; González-Neira, Anna; Greene, Mark H; Gronwald, Jacek; Guénel, Pascal; Gunter, Marc; Haeberle, Lothar; Haiman, Christopher A; Hamann, Ute; Hansen, Thomas V O; Hart, Steven; Healey, Sue; Heikkinen, Tuomas; Henderson, Brian E; Herzog, Josef; Hogervorst, Frans B L; Hollestelle, Antoinette; Hooning, Maartje J; Hoover, Robert N; Hopper, John L; Humphreys, Keith; Hunter, David J; Huzarski, Tomasz; Imyanitov, Evgeny N; Isaacs, Claudine; Jakubowska, Anna; James, Paul; Janavicius, Ramunas; Jensen, Uffe Birk; John, Esther M; Jones, Michael; Kabisch, Maria; Kar, Siddhartha; Karlan, Beth Y; Khan, Sofia; Khaw, Kay-Tee; Kibriya, Muhammad G; Knight, Julia A; Ko, Yon-Dschun; Konstantopoulou, Irene; Kosma, Veli-Matti; Kristensen, Vessela; Kwong, Ava; Laitman, Yael; Lambrechts, Diether; Lazaro, Conxi; Lee, Eunjung; Le Marchand, Loic; Lester, Jenny; Lindblom, Annika; Lindor, Noralane; Lindstrom, Sara; Liu, Jianjun; Long, Jirong; Lubinski, Jan; Mai, Phuong L; Makalic, Enes; Malone, Kathleen E; Mannermaa, Arto; Manoukian, Siranoush; Margolin, Sara; Marme, Frederik; Martens, John W M; McGuffog, Lesley; Meindl, Alfons; Miller, Austin; Milne, Roger L; Miron, Penelope; Montagna, Marco; Mazoyer, Sylvie; Mulligan, Anna M; Muranen, Taru A; Nathanson, Katherine L; Neuhausen, Susan L; Nevanlinna, Heli; Nordestgaard, Børge G; Nussbaum, Robert L; Offit, Kenneth; Olah, Edith; Olopade, Olufunmilayo I; Olson, Janet E; Osorio, Ana; Park, Sue K; Peeters, Petra H; Peissel, Bernard; Peterlongo, Paolo; Peto, Julian; Phelan, Catherine M; Pilarski, Robert; Poppe, Bruce; Pylkäs, Katri; Radice, Paolo; Rahman, Nazneen; Rantala, Johanna; Rappaport, Christine; Rennert, Gad; Richardson, Andrea; Robson, Mark; Romieu, Isabelle; Rudolph, Anja; Rutgers, Emiel J; Sanchez, Maria-Jose; Santella, Regina M; Sawyer, Elinor J; Schmidt, Daniel F; Schmidt, Marjanka K; Schmutzler, Rita K; Schumacher, Fredrick; Scott, Rodney; Senter, Leigha; Sharma, Priyanka; Simard, Jacques; Singer, Christian F; Sinilnikova, Olga M; Soucy, Penny; Southey, Melissa; Steinemann, Doris; Stenmark-Askmalm, Marie; Stoppa-Lyonnet, Dominique; Swerdlow, Anthony; Szabo, Csilla I; Tamimi, Rulla; Tapper, William; Teixeira, Manuel R; Teo, Soo-Hwang; Terry, Mary B; Thomassen, Mads; Thompson, Deborah; Tihomirova, Laima; Toland, Amanda E; Tollenaar, Robert A E M; Tomlinson, Ian; Truong, Thérèse; Tsimiklis, Helen; Teulé, Alex; Tumino, Rosario; Tung, Nadine; Turnbull, Clare; Ursin, Giski; van Deurzen, Carolien H M; van Rensburg, Elizabeth J; Varon-Mateeva, Raymonda; Wang, Zhaoming; Wang-Gohrke, Shan; Weiderpass, Elisabete; Weitzel, Jeffrey N; Whittemore, Alice; Wildiers, Hans; Winqvist, Robert; Yang, Xiaohong R; Yannoukakos, Drakoulis; Yao, Song; Zamora, M Pilar; Zheng, Wei; Hall, Per; Kraft, Peter; Vachon, Celine; Slager, Susan; Chenevix-Trench, Georgia; Pharoah, Paul D P; Monteiro, Alvaro A N; García-Closas, Montserrat; Easton, Douglas F; Antoniou, Antonis C

    2016-01-01

    Common variants in 94 loci have been associated with breast cancer including 15 loci with genome-wide significant associations (P<5 × 10(-8)) with oestrogen receptor (ER)-negative breast cancer and BRCA1-associated breast cancer risk. In this study, to identify new ER-negative susceptibility loci,

  6. Characterization and Modification of Electrospun Fiber Mats for Use in Composite Proton Exchange Membranes

    Science.gov (United States)

    Mannarino, Matthew Marchand

    Electrostatic fiber formation, or electrospinning, offers a particularly simple and robust method to create polymeric nanofibers of various sizes and morphologies. In electrospinning, a viscoelastic fluid is charged so that a liquid jet is ejected from the surface of the fluid (typically in the form of a drop supplied by a needle or spinneret) and collected on a grounded plate, creating a nonwoven fiber mat. Modification of the diameter of the fibers as well as the porosity, specific surface area, and mechanical properties of the mat allows one to tailor electrospun mats for specific applications. Despite the widespread and rapidly growing use of electrospinning in the fabrication of novel nanomaterials, there are no simple, universal methods of predicting, a priori, the properties of electrospun fibers from knowledge of the polymer solution properties and electrospinning operating conditions alone. Changing a single fluid or processing parameter can affect the jet and fiber formation through several mechanisms. For example, using a different solvent can change several properties of the electrospinning fluid, such as the dielectric constant, conductivity, surface tension, and solute-solvent interaction. The work in this thesis seeks to develop a simple relation for predicting terminal jet diameter during electrospinning, which accounts for solution viscoelasticity as well as solution conductivity and operating parameters that can be easily measured and controlled. The mechanical and tribological properties of electrospun fiber mats are of paramount importance to their utility as components in a variety of applications. Although some mechanical properties of these mats have been investigated previously, reports of their tribological properties are essentially nonexistent. In this thesis, electrospun nanofiber mats of poly(trimethyl hexamethylene terephthalamide) (PA 6(3)T) and poly(hexamethylene adipamide) (PA 6,6) are characterized mechanically and tribologically

  7. Effects of filamentous macroalgae mats on growth and survival of eelgrass, Zostera marina, seedlings

    DEFF Research Database (Denmark)

    Rasmussen, Jonas; Olesen, Birgit; Krause-Jensen, Dorte

    2012-01-01

    A laboratory experiment was conducted to assess the effect of filamentous algae mats on the performance of seedlings of the eelgrass, Zostera marina. The seedlings were covered by three levels (3, 6 and 9 cm) of natural (Chaetomorpha linum) and imitation algae mats and it was hypothesized that th...

  8. Effect of salinity on nitrogenase activity and composition of the active diazotrophic community in intertidal microbial mats

    NARCIS (Netherlands)

    Severin, I.; Confurius-Guns, V.; Stal, L.J.

    2012-01-01

    Microbial mats are often found in intertidal areas experiencing a large range of salinities. This study investigated the effect of changing salinities on nitrogenase activity and on the composition of the active diazotrophic community ( transcript libraries) of three types of microbial mats situated

  9. The ichthyofauna of drifting macrophyte mats in the Ivinhema River, upper Paraná River basin, Brazil

    Science.gov (United States)

    Bulla, C. K.; Gomes, Luiz Carlos; Miranda, Leandro E.; Agostinho, A. A.

    2011-01-01

    We describe the fish assemblages associated with drifting macrophyte mats and consider their possible role as dispersal vectors in the Ivinhema River, a major tributary of the upper Paraná River, Brazil. Fish associated with drifting mats were sampled in the main river channel during January and March 2005, when the wind and/or the increased water level were sufficient to transport macrophyte stands. Fish in the drifting mats were sampled with a floating sieve (4 m long x 2 m wide x 0.6 m high, and 2 mm mesh size). In the laboratory, larvae, juvenile, and adult fish were counted and identified to the lowest possible taxonomic level. In four drifting macrophyte mats we captured 218 individuals belonging to at least 28 species, 17 families, and 6 orders. Aphyocharax dentatus, Serrasalmus spp., and Trachelyopterus galeatus were the most abundant taxa associated with the mats, but species richness ranged from 6 to 24 species per mat. In addition, 85% of the total number of individuals caught was larvae and juveniles. Although preliminary and based on limited samples, this study of drifting macrophyte mats was the first one in the last unregulated stretch of the Paraná River remaining inside Brazilian territory, and alerts us to the potential role of macrophytes mats as dispersers of fish species in the region.

  10. Magnetoacoustic Tomography with Magnetic Induction (MAT-MI) for Imaging Electrical Conductivity of Biological Tissue: A Tutorial Review

    Science.gov (United States)

    Li, Xu; Yu, Kai; He, Bin

    2016-01-01

    Magnetoacoustic tomography with magnetic induction (MAT-MI) is a noninvasive imaging method developed to map electrical conductivity of biological tissue with millimeter level spatial resolution. In MAT-MI, a time-varying magnetic stimulation is applied to induce eddy current inside the conductive tissue sample. With the existence of a static magnetic field, the Lorentz force acting on the induced eddy current drives mechanical vibrations producing detectable ultrasound signals. These ultrasound signals can then be acquired to reconstruct a map related to the sample’s electrical conductivity contrast. This work reviews fundamental ideas of MAT-MI and major techniques developed in these years. First, the physical mechanisms underlying MAT-MI imaging are described including the magnetic induction and Lorentz force induced acoustic wave propagation. Second, experimental setups and various imaging strategies for MAT-MI are reviewed and compared together with the corresponding experimental results. In addition, as a recently developed reverse mode of MAT-MI, magneto-acousto-electrical tomography with magnetic induction (MAET-MI) is briefly reviewed in terms of its theory and experimental studies. Finally, we give our opinions on existing challenges and future directions for MAT-MI research. With all the reported and future technical advancement, MAT-MI has the potential to become an important noninvasive modality for electrical conductivity imaging of biological tissue. PMID:27542088

  11. Sequence analysis of Maturase K (matK): A chloroplast-encoding ...

    African Journals Online (AJOL)

    The application and utilization of sequence data has been found very informative in the characterization and phylogenetic relationship of different crops species. This study aimed to use bioinformatics tools to characterize the matK gene in some selected legumes with special reference to pigeon pea [cajanus cajan ...

  12. Mat-Rix-Toe: Improving Writing through a Game-Based Project in Linear Algebra

    Science.gov (United States)

    Graham-Squire, Adam; Farnell, Elin; Stockton, Julianna Connelly

    2014-01-01

    The Mat-Rix-Toe project utilizes a matrix-based game to deepen students' understanding of linear algebra concepts and strengthen students' ability to express themselves mathematically. The project was administered in three classes using slightly different approaches, each of which included some editing component to encourage the…

  13. Community phylogenetic analysis of moderately thermophilic cyanobacterial mats from China, the Philippines and Thailand.

    Science.gov (United States)

    Hongmei, Jing; Aitchison, Jonathan C; Lacap, Donnabella C; Peerapornpisal, Yuwadee; Sompong, Udomluk; Pointing, Stephen B

    2005-08-01

    Most community molecular studies of thermophilic cyanobacterial mats to date have focused on Synechococcus occurring at temperatures of approximately 50-65 degrees C. These reveal that molecular diversity exceeds that indicated by morphology, and that phylogeographic lineages exist. The moderately thermophilic and generally filamentous cyanobacterial mat communities occurring at lower temperatures have not previously been investigated at the community molecular level. Here we report community diversity in mats of 42-53 degrees C recovered from previously unstudied geothermal locations. Separation of 16S rRNA gene-defined genotypes from community DNA was achieved by DGGE. Genotypic diversity was greater than morphotype diversity in all mats sampled, although genotypes generally corresponded to observed morphotypes. Thirty-six sequences were recovered from DGGE bands. Phylogenetic analyses revealed these to form novel thermophilic lineages distinct from their mesophilic counterparts, within Calothrix, Cyanothece, Fischerella, Phormidium, Pleurocapsa, Oscillatoria and Synechococcus. Where filamentous cyanobacterial sequences belonging to the same genus were recovered from the same site, these were generally closely affiliated. Location-specific sequences were observed for some genotypes recovered from geochemically similar yet spatially separated sites, thus providing evidence for phylogeographic lineages that evolve in isolation. Other genotypes were more closely affiliated to geographically remote counterparts from similar habitats suggesting that adaptation to certain niches is also important.

  14. Welcome address / Mats Estonius, Toomas Hendrik Ilves, Eduardo Ibàñes, Uffe A. Baslev

    Index Scriptorium Estoniae

    2010-01-01

    Läänemere strateegia konverentsi avasõnad laususid Tallinna Ülikooli teadusprorektor Mats Estonius, Eesti Vabariigi president Toomas Hendrik Ilves ((vt. ka foto lk. 21), Hispaania Kuningriigi suursaadik Eestis Eduardo Ibáñes ja Taani Kuningriigi suursaadik Eestis Uffe A. Baslev

  15. MATS--Management Accounting Tutorial System. Version 1.0. Project Documentation.

    Science.gov (United States)

    Wardle, Andrew; O'Connor, Rodric

    The Management Accounting Tutorial System (MATS) is a management accounting database for a carpet manufacturing company. The system allows the display and output of monthly activities, and is intended to provide a means of illustrating the main topics of the second year management accounting course at Manchester University. The system itself…

  16. MATS--Management Accounting Tutorial System. Version 1.0. User Guide.

    Science.gov (United States)

    Wardle, Andrew; O'Connor, Rodric

    The Management Accounting Tutorial System (MATS) is a management accounting database for a carpet manufacturing company. The system allows the display and output of monthly activities, and is intended to provide a means of illustrating the main topics of the second year management accounting course at Manchester University. The system itself…

  17. The Use of Maltodextrin Matrices to Control the Release of Minerals from Fortified Maté

    Directory of Open Access Journals (Sweden)

    Miguel E. Schmalko

    2012-04-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE The aim of this research was to study the sensorial acceptance of a fortified food containing different minerals (calcium, magnesium and iron and to determine the actual quantities present (bioaccessibility when extracted in maté. A sensorial analysis was performed to compare sensorial quality of fortified and non-fortified maté. Although panelists identified differences between the fortified and non-fortified maté, only 3% of them commented on an unpleasant flavor. Sequential extraction assays were performed simulating maté consumption under laboratory conditions. Profile concentration diminished sharply after the second extraction. Magnesium was found to be completely extracted in the first 500 mL. Calcium and Iron were extracted in a very low percentage (29% and 25%, respectively. The outlet rate of the minerals was fitted to two models, and a good fitness (p < 0:001 in all cases was obtained.

  18. Modeling the pullout characteristics of welded wire mats embedded in silty sand

    International Nuclear Information System (INIS)

    Sampaco, C.L.; Anderson, L.R.; Nielson, M.R.

    1994-01-01

    This paper is an outgrowth of the on-going research on discrete finite element modeling of welded wire mesh reinforced soil structures such as the welded wire and RSE walls. The stiffness characteristics of the wire mesh-soil interfaces are modeled by a nonlinear hyperbolic relationship between the applied pullout stress and the associated mat placement. The relevant parameters are estimated from laboratory pullout tests that were conducted for welded wire mats embedded on silty sand. Since the bulk of the pullout resistance of welded wire mesh reinforcements is derived from the bearing resistance of the transverse wires that constitute the test mats. This feature permits proper evaluation of actual interface parameters for the actual reinforced soil structures in which the actual lengths of the mats are longer (i.e. more transverse members) than the specimen used in the laboratory pullout tests. The resulting pullout stress-displacement formulations are then verified by comparing the predicted pullout resistance to the existing specifications and design methods for estimated the pullout capacities of grid reinforcements. 22 refs., 13 figs

  19. Modular Algorithm Testbed Suite (MATS): A Software Framework for Automatic Target Recognition

    Science.gov (United States)

    2017-01-01

    NAVAL SURFACE WARFARE CENTER PANAMA CITY DIVISION PANAMA CITY, FL 32407-7001 TECHNICAL REPORT NSWC PCD TR-2017-004 MODULAR ...31-01-2017 Technical Modular Algorithm Testbed Suite (MATS): A Software Framework for Automatic Target Recognition DR...flexible platform to facilitate the development and testing of ATR algorithms. To that end, NSWC PCD has created the Modular Algorithm Testbed Suite

  20. Smart monitoring of fluid intake and bladder voiding using pressure sensitive mats.

    Science.gov (United States)

    Cohen-McFarlane, Madison; Green, James R; Knoefel, Frank; Goubran, Rafik

    2016-08-01

    Pressure sensitive mats have been used in noninvasive smart monitoring for a variety of problems including breathing rate monitoring, sleep monitoring, mobility, and weight. This paper describes a proof of concept application of pressure mats to monitor fluid intake/output (fluid cycle) events during the night. The ability to more accurately track such events has potential implications for monitoring those individuals who have nocturia, a condition where a person wakes at night to urinate. Data were collected from a healthy young female subject instructed to drink as much water as was comfortable (700mL) and lie in a supine position on a mattress located directly on three pressure mats. This was compared to an initial data set collected immediately after voiding but before drinking, 30 minutes after drinking, 60 minutes after drinking and a final data set after again voiding the bladder. The additional pressure from the 700mL of water was detectible and tracked over the course of the hour-long testing session under idealized conditions. This provides a proof-of-concept that nocturnal fluid intake and bladder voiding events can be tracked using non-invasive pressure-sensitive mats, however additional testing and development is required to achieve a deployable monitoring system.

  1. Eight-Week Traditional Mat Pilates Training-Program Effects on Adult Fitness Characteristics

    Science.gov (United States)

    Rogers, Kate; Gibson, Ann L.

    2009-01-01

    We investigated responses of adult, novice practitioners (n = 9) to an 8-week traditional mat Pilates program (P) that met 1 hr/day three times/week. Classes consisted primarily of beginner and intermediate level exercises. Compared to an active control group (C; n = 13) that showed no improvements, those in P significantly (p less than 0.05)…

  2. Rapid reactivation of cyanobacterial photosynthesis and migration upon rehydration of desiccated marine microbial mats

    NARCIS (Netherlands)

    Chennu, Arjun; Grinham, Alistair; Polerecky, Lubos; de Beer, Dirk; Al-Najjar, Mohammad A.A.

    2015-01-01

    Desiccated cyanobacterial mats are the dominant biological feature in the Earth's arid zones. While the response of desiccated cyanobacteria to rehydration is well-documented for terrestrial systems, information about the response in marine systems is lacking. We used high temporal resolution

  3. Cooperação jurídica internacional em matéria civil

    Directory of Open Access Journals (Sweden)

    Carmen Tiburcio

    2013-03-01

    Full Text Available O trabalho cuida dos sistemas e dos instrumentos de cooperação em matéria civil no âmbito do Mercosul: Protocolos de Las Leñas e Ouro Preto. Analisam-se os textos dos respectivos tratados, a jurisprudência brasileira e de outros países do Mercosul.

  4. Diatom-driven recolonization of microbial mat-dominated siliciclastic tidal flat sediments.

    Science.gov (United States)

    Pan, Jerónimo; Cuadrado, Diana G; Bournod, Constanza N

    2017-10-01

    Modern microbial mats and biofilms play a paramount role in sediment biostabilization. When sporadic storms affect tidal flats of Bahía Blanca Estuary, the underlying siliciclastic sediment is exposed by physical disruption of the mat, and in a few weeks' lapse, a microbial community re-establishes. With the objective of studying colonization patterns and the ecological succession of microorganisms at the scale of these erosional structures, these were experimentally made and their biological recolonization followed for 8 weeks, with replication in winter and spring. Motile pennate diatoms led the initial colonization following two distinct patterns: a dominance by Cylindrotheca closterium in winter and by naviculoid and nitzschioid diatoms in spring. During the first 7 days, cell numbers increased 2- to 17-fold. Cell densities further increased exhibiting sigmoidal community growth, reaching 2.9-8.9 × 106 cells cm-3 maxima around day 30; centric diatoms maintained low densities throughout. In 56 days after removal of the original mat, filamentous cyanobacteria that dominate mature mats did not establish a significant biomass, leading to the rejection of the hypothesis that cyanobacteria would drive the colonization. The observed dominance of pennate diatoms is attributed to extrinsic factors determined by tidal flooding, and intrinsic ones, e.g. motility, nutrient affinity and high growth rate. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Community ecology of hot spring cyanobacterial mats: predominant populations and their functional potential

    DEFF Research Database (Denmark)

    Klatt, C. G.; Wood, J. M.; Rusch, D. B.

    2011-01-01

    Phototrophic microbial mat communities from 60¿°C and 65¿°C regions in the effluent channels of Mushroom and Octopus Springs (Yellowstone National Park, WY, USA) were investigated by shotgun metagenomic sequencing. Analyses of assembled metagenomic sequences resolved six dominant chlorophototrophic...

  6. Contribution of Chloroflexus respiration to oxygen cycling in a hypersaline microbial mat from Lake Chiprana, Spain

    DEFF Research Database (Denmark)

    Polerecky, Lubos; Bachar, Ami; Schoon, Raphaela

    2007-01-01

    In dense stratified systems such as microbial mats, photosynthesis and respiration are coupled due to a tight spatial overlap between oxygen-producing and -consuming microorganisms. We combined microsensors and a membrane inlet mass spectrometer with two independent light sources emitting in the ...

  7. Organic matter degradation drives benthic cyanobacterial mat abundance on caribbean coral reefs

    NARCIS (Netherlands)

    Brocke, Hannah J.; Polerecky, Lubos; De Beer, Dirk; Weber, Miriam; Claudet, Joachim; Nugues, Maggy M.

    2015-01-01

    Benthic cyanobacterial mats (BCMs) are impacting coral reefs worldwide. However, the factors and mechanisms driving their proliferation are unclear. We conducted a multi-year survey around the Caribbean island of Curaçao, which revealed highest BCM abundance on sheltered reefs close to urbanised

  8. The Diffusive Boundary-Layer of Sediments - Oxygen Microgradients Over a Microbial Mat

    DEFF Research Database (Denmark)

    JØRGENSEN, BB; MARAIS, DJD

    1990-01-01

    Oxygen microelectrodes were used to analyze the distribution of the diffusive boundary layer (DBL) at the sedimen-water interface in relation to surface topography and flow velocity. The sediment, collected from saline ponds, was covered by a microbial mat that had high oxygen consumption rate...

  9. Clinical manifestation, serology marker & microscopic agglutination test (MAT) to mortality in human leptospirosis

    Science.gov (United States)

    Perdhana, S. A. P.; Susilo, R. S. B.; Arifin; Redhono, D.; Sumandjar, T.

    2018-03-01

    Leptospirosis is a potentially fatal zoonosis that is endemic in many tropical regions and causes large epidemics after heavy rainfall and flooding. Severe disease is estimated 5–15% of all human infections. Its mortality rate is 5-40%. MAT, isolation of the organism, or leptospiral DNA in PCR are used to confirm Leptospirosis. This cross-sectional analytic study recruited 26 hospitalized leptospirosis patients admitted to Dr. Moewardi Hospital Surakarta. The diagnosis was based on clinical, laboratory and epidemiological findings. The onset of the disease was the date when the first symptom started, and the end of the analysis was the date when the patient died or discharged. Modified Faine’s score ≥ 25 tend to die (45.5%) while modified Faine’s score 20 – 24 tend to heal (60%) (OR 1.250; CI 0.259-6.029; p=1.0). Seropositive IgM predicts mortality 7.8 times higher than seronegative IgM (OR 7.800; CI 1.162-52.353; p=0.038). MAT positive predict mortality 10.667 times higher than MAT negative (OR 10.667; CI 1.705-66.720; p=0.015). Clinical manifestation, MAT, and serologic marker are all correlated with mortality in Leptospirosis. However, statistically, clinical manifestation has an insignificant correlation.

  10. Mechanism study of selective heavy metal ion removal with polypyrrole-functionalized polyacrylonitrile nanofiber mats

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jianqiang; Luo, Chao [Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China); Qi, Genggeng [Department of Materials Science and Engineering, Cornell University, Ithaca, NY (United States); Pan, Kai, E-mail: pankai@mail.buct.edu.cn [Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China); Department of Materials Science and Engineering, Cornell University, Ithaca, NY (United States); Cao, Bing, E-mail: bcao@mail.buct.edu.cn [Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China)

    2014-10-15

    Graphical abstract: - Highlights: • PAN/PPy core/shell nanofiber used for Cr(VI) removal. • Adsorption mechanisms were investigated. • Selective adsorption performances were investigated. - Abstract: Polyacrylonitrile/polypyrrole (PAN/PPy) core/shell nanofiber mat was prepared through electrospinning followed by a simple chemical oxidation method. The polypyrrole-functionalized nanofiber mats showed selective adsorption performance for anions. The interaction between heavy metal anions and polypyrrole (especially the interaction between Cr{sub 2}O{sub 7}{sup 2−} and polypyrrole) during the adsorption process was studied. The results showed that the adsorption process included two steps: one was the anion exchange process between the Cl{sup −} and Cr(VI), and the other was the redox process for the Cr(VI) ions. The adsorption amount was related to the protonation time of the PAN/PPy nanofiber mat and increased as protonation time increased. Meanwhile, the Cr(VI) ions were reduced to Cr(III) through the reaction with amino groups of polypyrrole (from secondary amines to tertiary amines). PAN/PPy nanofiber mat showed high selectivity for Cr(VI), and the adsorption performance was nearly unaffected by other co-existing anions (Cl{sup −}, NO{sub 3}{sup −}, and SO{sub 4}{sup 2−}) except for PO{sub 4}{sup 3−} for the pH change.

  11. Super-Hydrophobic High Throughput Electrospun Cellulose Acetate (CA) Nanofibrous Mats as Oil Selective Sorbents

    Science.gov (United States)

    Han, Chao

    The threat of oil pollution increases with the expansion of oil exploration and production activities, as well as the industrial growth around the world. Use of sorbents is a common method to deal with the oil spills. In this work, an advanced sorbent technology is described. A series of non-woven Cellulose Acetate (CA) nanofibrous mats with a 3D fibrous structure were synthesized by a novel high-throughput electrospinning technique. The precursor was solutions of CA/ acetic acid-acetone in various concentrations. Among them, 15.0% CA exhibits a superhydrophobic surface property, with a water contact angle of 128.95°. Its oil sorption capacity is many times higher the oil sorption capacity of the best commercial sorbent available in the market. Also, it showed good buoyancy properties on the water both as dry-mat and oil-saturated mat. In addition, it is biodegradable, easily available, easily manufactured, so the CA nanofibrous mat is an excellent candidate as oil sorbent for oil spill in water treatment.

  12. Mechanism study of selective heavy metal ion removal with polypyrrole-functionalized polyacrylonitrile nanofiber mats

    International Nuclear Information System (INIS)

    Wang, Jianqiang; Luo, Chao; Qi, Genggeng; Pan, Kai; Cao, Bing

    2014-01-01

    Graphical abstract: - Highlights: • PAN/PPy core/shell nanofiber used for Cr(VI) removal. • Adsorption mechanisms were investigated. • Selective adsorption performances were investigated. - Abstract: Polyacrylonitrile/polypyrrole (PAN/PPy) core/shell nanofiber mat was prepared through electrospinning followed by a simple chemical oxidation method. The polypyrrole-functionalized nanofiber mats showed selective adsorption performance for anions. The interaction between heavy metal anions and polypyrrole (especially the interaction between Cr 2 O 7 2− and polypyrrole) during the adsorption process was studied. The results showed that the adsorption process included two steps: one was the anion exchange process between the Cl − and Cr(VI), and the other was the redox process for the Cr(VI) ions. The adsorption amount was related to the protonation time of the PAN/PPy nanofiber mat and increased as protonation time increased. Meanwhile, the Cr(VI) ions were reduced to Cr(III) through the reaction with amino groups of polypyrrole (from secondary amines to tertiary amines). PAN/PPy nanofiber mat showed high selectivity for Cr(VI), and the adsorption performance was nearly unaffected by other co-existing anions (Cl − , NO 3 − , and SO 4 2− ) except for PO 4 3− for the pH change

  13. In Situ Hydrogen Dynamics in a Hot Spring Microbial Mat during a Diel Cycle

    DEFF Research Database (Denmark)

    Revsbech, Niels Peter; Trampe, Erik Christian Løvbjerg; Lichtenberg, Mads

    2016-01-01

    decreasing to about 11 mol H2 liter1 just before sunrise. Another pulse of H2 production, reaching a peak concentration of 46 mol H2 liter1, was found in the early morning under dim light conditions too low to induce accumulation of O2 in the mat. The light stimulation of H2 accumulation indicated...

  14. Association analysis identifies 65 new breast cancer risk loci

    DEFF Research Database (Denmark)

    Michailidou, Kyriaki; Lindström, Sara; Dennis, Joe

    2017-01-01

    Breast cancer risk is influenced by rare coding variants in susceptibility genes, such as BRCA1, and many common, mostly non-coding variants. However, much of the genetic contribution to breast cancer risk remains unknown. Here we report the results of a genome-wide association study of breast...... cancer in 122,977 cases and 105,974 controls of European ancestry and 14,068 cases and 13,104 controls of East Asian ancestry. We identified 65 new loci that are associated with overall breast cancer risk at P risk single-nucleotide polymorphisms in these loci fall......-nucleotide polymorphisms in regulatory features was 2-5-fold enriched relative to the genome-wide average, with strong enrichment for particular transcription factor binding sites. These results provide further insight into genetic susceptibility to breast cancer and will improve the use of genetic risk scores...

  15. Seven newly identified loci for autoimmune thyroid disease.

    Science.gov (United States)

    Cooper, Jason D; Simmonds, Matthew J; Walker, Neil M; Burren, Oliver; Brand, Oliver J; Guo, Hui; Wallace, Chris; Stevens, Helen; Coleman, Gillian; Franklyn, Jayne A; Todd, John A; Gough, Stephen C L

    2012-12-01

    Autoimmune thyroid disease (AITD), including Graves' disease (GD) and Hashimoto's thyroiditis (HT), is one of the most common of the immune-mediated diseases. To further investigate the genetic determinants of AITD, we conducted an association study using a custom-made single-nucleotide polymorphism (SNP) array, the ImmunoChip. The SNP array contains all known and genotype-able SNPs across 186 distinct susceptibility loci associated with one or more immune-mediated diseases. After stringent quality control, we analysed 103 875 common SNPs (minor allele frequency >0.05) in 2285 GD and 462 HT patients and 9364 controls. We found evidence for seven new AITD risk loci (P test derived significance threshold), five at locations previously associated and two at locations awaiting confirmation, with other immune-mediated diseases.

  16. Mats and LaSpec: High-precision experiments using ion traps and lasers at Fair

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, D.; Lallena, A.M.; Blaum, K.; Bohm, C.; Cakirli, R.B.; Crespo Lopez-Urrutia, J.R.; Eliseev, S.; Ketelaer, J.; Kreim, M.S.; Kowalska, M.; Litvinov, Y.A.; Nagy, S.; Neidherr, D.; Repp, J.; Roux, C.; Schabinger, B.; Ullrich, J.; Nortershauser, W.; Eberhardt, K.; Geppert, C.; Kramer, J.; Krieger, A.; Sanchez, R.; Ahammed, M.; Das, P.; Ray, A.; Algora, A.; Rubio, B.; Tain, J.L.; Audi, G.; Lunney, D.; Naimi, S.; Aysto, J.; Jokinen, A.; Kolhinen, V.; Moore, I.; Beck, D.; Block, M.; Geissel, H.; Heinz, S.; Herfurth, F.; Litvinov, Y.A.; Minaya-Ramirez, E.; Plab, W.R.; Quint, W.; Scheidenberger, C.; Winkler, M.; Bender, M.; Billowes, J.; Campbell, P.; Flanagan, K.T.; Schwarz, S.; Bollen, G.; Ferrer, R.; George, S.; Kester, O.; Brodeur, M.; Brunner, T.; Delheij, P.; Dilling, J.; Ettenauer, S.; Lapierre, A.; Bushaw, B.A.; Cano-Ott, D.; Martinez, T.; Cortes, G.; Gomez-Hornillos, M.B.; Dax, A.; Herlert, A.; Yordanov, D.; De, A.; Dickel, T.; Geissel, H.; Jesch, C.; Kuhl, T.; Petrick, M.; PlaB, W.R.; Scheidenberger, C.; Garcia-Ramos, J.E.; Gartzke, E.; Habs, D.; Szerypo, J.; Thirolf, P.G.; Weber, C.; Gusev, Y.; Nesterenko, D.; Novikov, Y.N.; Popov, A.; Seliverstov, M.; Vasiliev, A.; Vorobjev, G.; Heenen, P.H.; Marx, G.; Schweikhard, L.; Ziegler, F.; Hobein, M.; Schuch, R.; Solders, A.; Suhonen, M.; Huber, G.; Wendt, K.; Huyse, M.; Koudriavtsev, I.; Neyens, G.; Van Duppen, P.; Le Blanc, F.; Matos, M.; Reinhard, P.G.; Schneider, D.

    2010-05-15

    Nuclear ground state properties including mass, charge radii, spins and moments can be determined by applying atomic physics techniques such as Penning-trap based mass spectrometry and laser spectroscopy. The MATS and LaSpec setups at the low-energy beamline at FAIR will allow us to extend the knowledge of these properties further into the region far from stability. With MATS (Precision Measurements of very short-lived nuclei using an Advanced Trapping System for highly-charged ions) at FAIR we aim to apply several techniques to very short-lived radionuclides: High-accuracy mass measurements, in-trap conversion electron and alpha spectroscopy, and trap-assisted spectroscopy. The experimental setup of MATS is a unique combination of an electron beam ion trap for charge breeding, ion traps for beam preparation, and a high-precision Penning trap system for mass measurements and decay studies. For the mass measurements, MATS offers both a high accuracy and a high sensitivity. A relative mass uncertainty of 10{sup -9} can be reached by employing highly-charged ions and a non-destructive Fourier-Transform Ion-Cyclotron-Resonance (FT-ICR) detection technique on single stored ions. Decay studies in ion traps will become possible with MATS. Laser spectroscopy of radioactive isotopes and isomers is an efficient and model-independent approach for the determination of nuclear ground and isomeric state properties. Hyperfine structures and isotope shifts in electronic transitions exhibit readily accessible information on the nuclear spin, magnetic dipole and electric quadrupole moments as well as root-mean-square charge radii. The accuracy of laser-spectroscopic-determined nuclear properties is very high while requirements concerning production rates are moderate. This Technical Design Report describes a new Penning trap mass spectrometry setup as well as a number of complementary experimental devices for laser spectroscopy. Since MATS and LaSpec require high-quality low

  17. Mats and LaSpec: High-precision experiments using ion traps and lasers at Fair

    International Nuclear Information System (INIS)

    Rodriguez, D.; Lallena, A.M.; Blaum, K.; Bohm, C.; Cakirli, R.B.; Crespo Lopez-Urrutia, J.R.; Eliseev, S.; Ketelaer, J.; Kreim, M.S.; Kowalska, M.; Litvinov, Y.A.; Nagy, S.; Neidherr, D.; Repp, J.; Roux, C.; Schabinger, B.; Ullrich, J.; Nortershauser, W.; Eberhardt, K.; Geppert, C.; Kramer, J.; Krieger, A.; Sanchez, R.; Ahammed, M.; Das, P.; Ray, A.; Algora, A.; Rubio, B.; Tain, J.L.; Audi, G.; Lunney, D.; Naimi, S.; Aysto, J.; Jokinen, A.; Kolhinen, V.; Moore, I.; Beck, D.; Block, M.; Geissel, H.; Heinz, S.; Herfurth, F.; Litvinov, Y.A.; Minaya-Ramirez, E.; Plab, W.R.; Quint, W.; Scheidenberger, C.; Winkler, M.; Bender, M.; Billowes, J.; Campbell, P.; Flanagan, K.T.; Schwarz, S.; Bollen, G.; Ferrer, R.; George, S.; Kester, O.; Brodeur, M.; Brunner, T.; Delheij, P.; Dilling, J.; Ettenauer, S.; Lapierre, A.; Bushaw, B.A.; Cano-Ott, D.; Martinez, T.; Cortes, G.; Gomez-Hornillos, M.B.; Dax, A.; Herlert, A.; Yordanov, D.; De, A.; Dickel, T.; Geissel, H.; Jesch, C.; Kuhl, T.; Petrick, M.; PlaB, W.R.; Scheidenberger, C.; Garcia-Ramos, J.E.; Gartzke, E.; Habs, D.; Szerypo, J.; Thirolf, P.G.; Weber, C.; Gusev, Y.; Nesterenko, D.; Novikov, Y.N.; Popov, A.; Seliverstov, M.; Vasiliev, A.; Vorobjev, G.; Heenen, P.H.; Marx, G.; Schweikhard, L.; Ziegler, F.; Hobein, M.; Schuch, R.; Solders, A.; Suhonen, M.; Huber, G.; Wendt, K.; Huyse, M.; Koudriavtsev, I.; Neyens, G.; Van Duppen, P.; Le Blanc, F.; Matos, M.; Reinhard, P.G.; Schneider, D.

    2010-01-01

    Nuclear ground state properties including mass, charge radii, spins and moments can be determined by applying atomic physics techniques such as Penning-trap based mass spectrometry and laser spectroscopy. The MATS and LaSpec setups at the low-energy beamline at FAIR will allow us to extend the knowledge of these properties further into the region far from stability. With MATS (Precision Measurements of very short-lived nuclei using an Advanced Trapping System for highly-charged ions) at FAIR we aim to apply several techniques to very short-lived radionuclides: High-accuracy mass measurements, in-trap conversion electron and alpha spectroscopy, and trap-assisted spectroscopy. The experimental setup of MATS is a unique combination of an electron beam ion trap for charge breeding, ion traps for beam preparation, and a high-precision Penning trap system for mass measurements and decay studies. For the mass measurements, MATS offers both a high accuracy and a high sensitivity. A relative mass uncertainty of 10 -9 can be reached by employing highly-charged ions and a non-destructive Fourier-Transform Ion-Cyclotron-Resonance (FT-ICR) detection technique on single stored ions. Decay studies in ion traps will become possible with MATS. Laser spectroscopy of radioactive isotopes and isomers is an efficient and model-independent approach for the determination of nuclear ground and isomeric state properties. Hyperfine structures and isotope shifts in electronic transitions exhibit readily accessible information on the nuclear spin, magnetic dipole and electric quadrupole moments as well as root-mean-square charge radii. The accuracy of laser-spectroscopic-determined nuclear properties is very high while requirements concerning production rates are moderate. This Technical Design Report describes a new Penning trap mass spectrometry setup as well as a number of complementary experimental devices for laser spectroscopy. Since MATS and LaSpec require high-quality low-energy beams

  18. Localized electron transfer rates and microelectrode-based enrichment of microbial communities within a phototrophic microbial mat

    Directory of Open Access Journals (Sweden)

    Jerome eBabauta

    2014-01-01

    Full Text Available Phototrophic microbial mats frequently exhibit sharp, light-dependent redox gradients that regulate microbial respiration on specific electron acceptors as a function of depth. In this work, a benthic phototrophic microbial mat from Hot Lake, a hypersaline, epsomitic lake located near Oroville in north-central Washington, was used to develop a microscale electrochemical method to study local electron transfer processes within the mat. To characterize the physicochemical variables influencing electron transfer, we initially quantified redox potential, pH and dissolved oxygen gradients by depth in the mat under photic and aphotic conditions. We further demonstrated that power output of a mat fuel cell was light-dependent. To study local electron transfer processes, we deployed a microscale electrode (microelectrode with tip size ~20 µm. To enrich a subset of microorganisms capable of interacting with the microelectrode, we anodically polarized the microelectrode in the mat. Subsequently, to characterize the microelectrode-associated community and compare it to the neighboring mat community, we performed amplicon sequencing of the V1-V3 region of the 16S gene. Differences in Bray-Curtis beta diversity, illustrated by large changes in relative abundance at the phylum level, suggested successful enrichment of specific mat community members on the microelectrode surface. The microelectrode-associated community exhibited substantially reduced alpha diversity and elevated relative abundances of Prosthecochloris, Loktanella, Catellibacterium, other unclassified members of Rhodobacteraceae, Thiomicrospira, and Limnobacter, compared with the community at an equivalent depth in the mat. Our results suggest that local electron transfer to an anodically polarized microelectrode selected for a specific microbial population, with substantially more abundance and diversity of sulfur-oxidizing phylotypes compared with the neighboring mat community.

  19. Localized electron transfer rates and microelectrode-based enrichment of microbial communities within a phototrophic microbial mat.

    Science.gov (United States)

    Babauta, Jerome T; Atci, Erhan; Ha, Phuc T; Lindemann, Stephen R; Ewing, Timothy; Call, Douglas R; Fredrickson, James K; Beyenal, Haluk

    2014-01-01

    Phototrophic microbial mats frequently exhibit sharp, light-dependent redox gradients that regulate microbial respiration on specific electron acceptors as a function of depth. In this work, a benthic phototrophic microbial mat from Hot Lake, a hypersaline, epsomitic lake located near Oroville in north-central Washington, was used to develop a microscale electrochemical method to study local electron transfer processes within the mat. To characterize the physicochemical variables influencing electron transfer, we initially quantified redox potential, pH, and dissolved oxygen gradients by depth in the mat under photic and aphotic conditions. We further demonstrated that power output of a mat fuel cell was light-dependent. To study local electron transfer processes, we deployed a microscale electrode (microelectrode) with tip size ~20 μm. To enrich a subset of microorganisms capable of interacting with the microelectrode, we anodically polarized the microelectrode at depth in the mat. Subsequently, to characterize the microelectrode-associated community and compare it to the neighboring mat community, we performed amplicon sequencing of the V1-V3 region of the 16S gene. Differences in Bray-Curtis beta diversity, illustrated by large changes in relative abundance at the phylum level, suggested successful enrichment of specific mat community members on the microelectrode surface. The microelectrode-associated community exhibited substantially reduced alpha diversity and elevated relative abundances of Prosthecochloris, Loktanella, Catellibacterium, other unclassified members of Rhodobacteraceae, Thiomicrospira, and Limnobacter, compared with the community at an equivalent depth in the mat. Our results suggest that local electron transfer to an anodically polarized microelectrode selected for a specific microbial population, with substantially more abundance and diversity of sulfur-oxidizing phylotypes compared with the neighboring mat community.

  20. Allele frequency distribution for 21 autosomal STR loci in Nepal.

    Science.gov (United States)

    Kraaijenbrink, T; van Driem, G L; Opgenort, J R M L; Tuladhar, N M; de Knijff, P

    2007-05-24

    The allele frequency distributions of 21 autosomal loci contained in the AmpFlSTR Identifiler, the Powerplex 16 and the FFFL multiplex PCR kits, was studied in 953 unrelated individuals from Nepal. Several new alleles (i.e. not yet reported in the NIST Short Tandem Repeat DNA Internet DataBase [http://www.cstl.nist.gov/biotech/strbase/]) have been detected in the process.

  1. Characteristics of Japanese inflammatory bowel disease susceptibility loci.

    Science.gov (United States)

    Arimura, Yoshiaki; Isshiki, Hiroyuki; Onodera, Kei; Nagaishi, Kanna; Yamashita, Kentaro; Sonoda, Tomoko; Matsumoto, Takayuki; Takahashi, Atsushi; Takazoe, Masakazu; Yamazaki, Keiko; Kubo, Michiaki; Fujimiya, Mineko; Imai, Kohzoh; Shinomura, Yasuhisa

    2014-08-01

    There are substantial differences in inflammatory bowel disease (IBD) genetics depending on the populations examined. We aimed to identify Japanese population-specific or true culprit susceptibility genes through a meta-analysis of past genetic studies of Japanese IBD. For this study, we reviewed 2,703 articles. The review process consisted of three screening stages: we initially searched for relevant studies and then relevant single nucleotide polymorphisms (SNPs). Finally, we adjusted them for the meta-analysis. To maximize our chances of analysis, we introduced proxy SNPs during the first stage. To minimize publication bias, no significant SNPs and solitary SNPs without pairs were combined to be reconsidered during the third stage. Additionally, two SNPs were newly genotyped. Finally, we conducted a meta-analysis of 37 published studies in 50 SNPs located at 22 loci corresponding to the total number of 4,853 Crohn's disease (CD), 5,612 ulcerative colitis (UC) patients, and 14,239 healthy controls. We confirmed that the NKX2-3 polymorphism is associated with common susceptibility to IBD and that HLA-DRB1*0450 alleles increase susceptibility to CD but reduce risk for UC while HLA-DRB1*1502 alleles increase susceptibility to UC but reduce CD risk. Moreover, we found individual disease risk loci: TNFSF15 and TNFα to CD and HLA-B*5201, and NFKBIL1 to UC. The genetic risk of HLA was substantially high (odds ratios ranged from 1.54 to 2.69) while that of common susceptibility loci to IBD was modest (odds ratio ranged from 1.13 to 1.24). Results indicate that Japanese IBD susceptibility loci identified by the meta-analysis are closely associated with the HLA regions.

  2. The signature of positive selection at randomly chosen loci.

    OpenAIRE

    Przeworski, Molly

    2002-01-01

    In Drosophila and humans, there are accumulating examples of loci with a significant excess of high-frequency-derived alleles or high levels of linkage disequilibrium, relative to a neutral model of a random-mating population of constant size. These are features expected after a recent selective sweep. Their prevalence suggests that positive directional selection may be widespread in both species. However, as I show here, these features do not persist long after the sweep ends: The high-frequ...

  3. Genetic polymorphisms of 20 autosomal STR loci in the Vietnamese population from Yunnan Province, Southwest China.

    Science.gov (United States)

    Zhang, Xiufeng; Hu, Liping; Du, Lei; Nie, Aiting; Rao, Min; Pang, Jing Bo; Nie, Shengjie

    2017-05-01

    The genetic polymorphisms of 20 autosomal short tandem repeat (STR) loci included in the PowerPlex® 21 kit were evaluated in 522 healthy unrelated Vietnamese from Yunnan, China. All of the loci reached the Hardy-Weinberg equilibrium. These loci were examined to determine allele frequencies and forensic statistical parameters. The combined discrimination power and probability of excluding paternity of the 20 STR loci were 0.999999999999999999999991 26 and 0.999999975, respectively. Results suggested that the 20 STR loci are highly polymorphic, which is suitable for forensic personal identification and paternity testing.

  4. Isolation and characterization of 21 polymorphic microsatellite loci in the Japanese dace (Tribolodon hakonensis)

    Science.gov (United States)

    Koizumi, Noriyuki; Quinn, Thomas W.; Park, Myeongsoo; Fike, Jennifer A.; Nishida, Kazuya; Takemura, Takeshi; Watabe, Keiji; Mori, Atsushi

    2011-01-01

    Twenty one polymorphic microsatellite loci for the Japanese dace (Tribolodon hakonensis) were isolated and characterized. The number of observed alleles per locus in 32 individuals ranged from 3 to 30. The observed and expected heterozygosities ranged from 0.125 to 0.969 and from 0.175 to 0.973, respectively. All loci conformed to Hardy–Weinberg equilibrium, no linkage disequilibrium was observed between pairs of loci and no loci showed evidence of null alleles. These microsatellite loci will be useful for investigating the intraspecific genetic variation and population structure of this species.

  5. PERMANENT GENETIC RESOURCES: Isolation and characterization of polymorphic microsatellite loci in common evening primrose (Oenothera biennis).

    Science.gov (United States)

    Larson, E L; Bogdanowicz, S M; Agrawal, A A; Johnson, M T J; Harrison, R G

    2008-03-01

    We developed nine polymorphic microsatellite loci for evening primrose (Oenothera biennis). These loci have two to 18 alleles per locus and observed heterozygosities ranging from 0 to 0.879 in a sample of 34 individuals. In a pattern consistent with the functionally asexual reproductive system of this species, 17/36 pairs of loci revealed significant linkage disequilibrium and three loci showed significant deviations from Hardy-Weinberg equilibrium. The loci will be informative in identifying genotypes in multigenerational field studies to assess changes in genotype frequencies. © 2007 The Authors.

  6. PHOTOGRAPHY AS A MEANS OF DEPICTING GENIUS LOCI?

    Directory of Open Access Journals (Sweden)

    Iulia DOROFTEI

    2016-10-01

    Full Text Available The paper aims to explore the concept of genius loci (spirit of a place starting from Christian Norberg-Schulz’s notable work “Genius Loci: Towards a Phenomenology of Architecture” and to reflect on the possibility of capturing the spirit of a place through photography. The problem arises in the context of a predominantly visual culture, where photography has become an accesible and omnipresent means of experiencing the world and, therefore, considered a convenient tool for gaining (a type of knowledge. A photographic method of exploring the spirirt of the place could serve in understanding local characteristics, in identifying the elements that make a place unique and recognizible. Norberg-Schulz’s position and other views on the concept of genius loci have been analysed. A photo-essay was employed in order to explore the spirit of the old town of Chefchaouen in Morocco and the ambiguity and dual nature of the concept. A critical reflection was conducted with respect to the results.

  7. The Red Queen lives: Epistasis between linked resistance loci.

    Science.gov (United States)

    Metzger, César M J A; Luijckx, Pepijn; Bento, Gilberto; Mariadassou, Mahendra; Ebert, Dieter

    2016-02-01

    A popular theory explaining the maintenance of genetic recombination (sex) is the Red Queen Theory. This theory revolves around the idea that time-lagged negative frequency-dependent selection by parasites favors rare host genotypes generated through recombination. Although the Red Queen has been studied for decades, one of its key assumptions has remained unsupported. The signature host-parasite specificity underlying the Red Queen, where infection depends on a match between host and parasite genotypes, relies on epistasis between linked resistance loci for which no empirical evidence exists. We performed 13 genetic crosses and tested over 7000 Daphnia magna genotypes for resistance to two strains of the bacterial pathogen Pasteuria ramosa. Results reveal the presence of strong epistasis between three closely linked resistance loci. One locus masks the expression of the other two, while these two interact to produce a single resistance phenotype. Changing a single allele on one of these interacting loci can reverse resistance against the tested parasites. Such a genetic mechanism is consistent with host and parasite specificity assumed by the Red Queen Theory. These results thus provide evidence for a fundamental assumption of this theory and provide a genetic basis for understanding the Red Queen dynamics in the Daphnia-Pasteuria system. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  8. Genome-wide association study identifies five new schizophrenia loci.

    LENUS (Irish Health Repository)

    Ripke, Stephan

    2011-10-01

    We examined the role of common genetic variation in schizophrenia in a genome-wide association study of substantial size: a stage 1 discovery sample of 21,856 individuals of European ancestry and a stage 2 replication sample of 29,839 independent subjects. The combined stage 1 and 2 analysis yielded genome-wide significant associations with schizophrenia for seven loci, five of which are new (1p21.3, 2q32.3, 8p23.2, 8q21.3 and 10q24.32-q24.33) and two of which have been previously implicated (6p21.32-p22.1 and 18q21.2). The strongest new finding (P = 1.6 × 10(-11)) was with rs1625579 within an intron of a putative primary transcript for MIR137 (microRNA 137), a known regulator of neuronal development. Four other schizophrenia loci achieving genome-wide significance contain predicted targets of MIR137, suggesting MIR137-mediated dysregulation as a previously unknown etiologic mechanism in schizophrenia. In a joint analysis with a bipolar disorder sample (16,374 affected individuals and 14,044 controls), three loci reached genome-wide significance: CACNA1C (rs4765905, P = 7.0 × 10(-9)), ANK3 (rs10994359, P = 2.5 × 10(-8)) and the ITIH3-ITIH4 region (rs2239547, P = 7.8 × 10(-9)).

  9. Novel multiple sclerosis susceptibility loci implicated in epigenetic regulation

    Science.gov (United States)

    Andlauer, Till F. M.; Buck, Dorothea; Antony, Gisela; Bayas, Antonios; Bechmann, Lukas; Berthele, Achim; Chan, Andrew; Gasperi, Christiane; Gold, Ralf; Graetz, Christiane; Haas, Jürgen; Hecker, Michael; Infante-Duarte, Carmen; Knop, Matthias; Kümpfel, Tania; Limmroth, Volker; Linker, Ralf A.; Loleit, Verena; Luessi, Felix; Meuth, Sven G.; Mühlau, Mark; Nischwitz, Sandra; Paul, Friedemann; Pütz, Michael; Ruck, Tobias; Salmen, Anke; Stangel, Martin; Stellmann, Jan-Patrick; Stürner, Klarissa H.; Tackenberg, Björn; Then Bergh, Florian; Tumani, Hayrettin; Warnke, Clemens; Weber, Frank; Wiendl, Heinz; Wildemann, Brigitte; Zettl, Uwe K.; Ziemann, Ulf; Zipp, Frauke; Arloth, Janine; Weber, Peter; Radivojkov-Blagojevic, Milena; Scheinhardt, Markus O.; Dankowski, Theresa; Bettecken, Thomas; Lichtner, Peter; Czamara, Darina; Carrillo-Roa, Tania; Binder, Elisabeth B.; Berger, Klaus; Bertram, Lars; Franke, Andre; Gieger, Christian; Herms, Stefan; Homuth, Georg; Ising, Marcus; Jöckel, Karl-Heinz; Kacprowski, Tim; Kloiber, Stefan; Laudes, Matthias; Lieb, Wolfgang; Lill, Christina M.; Lucae, Susanne; Meitinger, Thomas; Moebus, Susanne; Müller-Nurasyid, Martina; Nöthen, Markus M.; Petersmann, Astrid; Rawal, Rajesh; Schminke, Ulf; Strauch, Konstantin; Völzke, Henry; Waldenberger, Melanie; Wellmann, Jürgen; Porcu, Eleonora; Mulas, Antonella; Pitzalis, Maristella; Sidore, Carlo; Zara, Ilenia; Cucca, Francesco; Zoledziewska, Magdalena; Ziegler, Andreas; Hemmer, Bernhard; Müller-Myhsok, Bertram

    2016-01-01

    We conducted a genome-wide association study (GWAS) on multiple sclerosis (MS) susceptibility in German cohorts with 4888 cases and 10,395 controls. In addition to associations within the major histocompatibility complex (MHC) region, 15 non-MHC loci reached genome-wide significance. Four of these loci are novel MS susceptibility loci. They map to the genes L3MBTL3, MAZ, ERG, and SHMT1. The lead variant at SHMT1 was replicated in an independent Sardinian cohort. Products of the genes L3MBTL3, MAZ, and ERG play important roles in immune cell regulation. SHMT1 encodes a serine hydroxymethyltransferase catalyzing the transfer of a carbon unit to the folate cycle. This reaction is required for regulation of methylation homeostasis, which is important for establishment and maintenance of epigenetic signatures. Our GWAS approach in a defined population with limited genetic substructure detected associations not found in larger, more heterogeneous cohorts, thus providing new clues regarding MS pathogenesis. PMID:27386562

  10. Genetic maps of polymorphic DNA loci on rat chromosome 1

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Yan-Ping; Remmers, E.F.; Longman, R.E. [National Institutes of Health, Bethesda, MD (United States)] [and others

    1996-09-01

    Genetic linkage maps of loci defined by polymorphic DNA markers on rat chromosome 1 were constructed by genotyping F2 progeny of F344/N x LEW/N, BN/SsN x LEW/N, and DA/Bkl x F344/Hsd inbred rat strains. In total, 43 markers were mapped, of which 3 were restriction fragment length polymorphisms and the others were simple sequence length polymorphisms. Nineteen of these markers were associated with genes. Six markers for five genes, {gamma}-aminobutyric acid receptor {beta}3 (Gabrb3), syntaxin 2 (Stx2), adrenergic receptor {beta}3 (Gabrb3), syntaxin 2 (Stx2), adrenergic receptor {beta}1 (Adrb1), carcinoembryonic antigen gene family member 1 (Cgm1), and lipogenic protein S14 (Lpgp), and 20 anonymous loci were not previously reported. Thirteen gene loci (Myl2, Aldoa, Tnt, Igf2, Prkcg, Cgm4, Calm3, Cgm3, Psbp1, Sa, Hbb, Ins1, and Tcp1) were previously mapped. Comparative mapping analysis indicated that the large portion of rat chromosome 1 is homologous to mouse chromosome 7, although the homologous to mouse chromosome 7, although the homologs of two rat genes are located on mouse chromosomes 17 and 19. Homologs of the rat chromosome 1 genes that we mapped are located on human chromosomes 6, 10, 11, 12, 15, 16, and 19. 38 refs., 1 fig., 3 tabs.

  11. Four loci explain 83% of size variation in the horse.

    Directory of Open Access Journals (Sweden)

    Shokouh Makvandi-Nejad

    Full Text Available Horse body size varies greatly due to intense selection within each breed. American Miniatures are less than one meter tall at the withers while Shires and Percherons can exceed two meters. The genetic basis for this variation is not known. We hypothesize that the breed population structure of the horse should simplify efforts to identify genes controlling size. In support of this, here we show with genome-wide association scans (GWAS that genetic variation at just four loci can explain the great majority of horse size variation. Unlike humans, which are naturally reproducing and possess many genetic variants with weak effects on size, we show that horses, like other domestic mammals, carry just a small number of size loci with alleles of large effect. Furthermore, three of our horse size loci contain the LCORL, HMGA2 and ZFAT genes that have previously been found to control human height. The LCORL/NCAPG locus is also implicated in cattle growth and HMGA2 is associated with dog size. Extreme size diversification is a hallmark of domestication. Our results in the horse, complemented by the prior work in cattle and dog, serve to pinpoint those very few genes that have played major roles in the rapid evolution of size during domestication.

  12. Rapid spectrofluorometric screening of poly-hydroxyalkanoate-producing bacteria from microbial mats.

    Science.gov (United States)

    Berlanga, Mercedes; Montero, M T; Fernández-Borrell, Jordi; Guerrero, Ricardo

    2006-06-01

    Microbial mat ecosystems are characterized by both seasonal and diel fluctuations in several physicochemical variables, so that resident microorganisms must frequently adapt to the changing conditions of their environment. It has been pointed out that, under stress conditions, bacterial cells with higher contents of poly-hydroxyalkanoates (PHA) survive longer than those with lower PHA content. In the present study, PHA-producing strains from Ebro Delta microbial mats were selected using the Nile red dying technique and the relative accumulation of PHA was monitored during further laboratory cultivation. The number of heterotrophic isolates in trypticase soy agar (TSA) was ca. 107 colony-forming units/g microbial mat. Of these, 100 randomly chosen colonies were replicated on mineral salt agar limited in nitrogen, and Nile red was added to the medium to detect PHA. Orange fluorescence, produced upon binding of the dye to polymer granules in the cell, was detected in approximately 10% of the replicated heterotrophic isolates. The kinetics of PHA accumulation in Pseudomonas putida, and P. oleovorans were compared with those of several of the environmental isolates spectrofluorometry. PHA accumulation, measured as relative fluorescence intensity, resulted in a steady-state concentration after 48 h of incubation in all strains assayed. At 72 h, the maximum fluorescence intensity of each strain incubated with glucose and fructose was usually similar. MAT-28 strain accumulated more PHA than the other isolates. The results show that data obtained from environmental isolates can highly improve studies based on modeling-simulation programs, and that microbial mats constitute an excellent source for the isolation of PHA-producing strains with industrial applications.

  13. Total mercury and methyl-mercury contents and accumulation in polar microbial mats.

    Science.gov (United States)

    Camacho, Antonio; Rochera, Carlos; Hennebelle, Raphaëlle; Ferrari, Christophe; Quesada, Antonio

    2015-03-15

    Although polar regions are considered isolated and pristine areas, the organisms that inhabit these zones are exposed to global pollution. Heavy metals, such as mercury, are global pollutants and can reach almost any location on Earth. Mercury may come from natural, volcanic or geological sources, or result from anthropogenic sources, in particular industrial or mining activities. In this study, we have investigated one of the most prominent biological non-marine communities in both polar regions, microbial mats, in terms of their Hg and methyl-mercury (MeHg) concentrations and accumulation capacities. The main hypotheses posed argued on the importance of different factors, and to test them, we have measured Hg concentrations in microbial mats that were collected from 6 locations in different ecological situations. For this purpose, the direct anthropogenic impacts, volcanic influences, proximity to the seashore, latitudinal gradients and C contents were investigated. Our results show that, other than the direct anthropogenic influence, none of the other hypotheses alone satisfactorily explains the Hg content in microbial mats. In contrast, the MeHg contents were noticeably different between the investigated locations, with a higher proportion of MeHg on the McMurdo Ice Shelf (Antarctica) and a lower proportion on Ward Hunt Island (High Arctic). Furthermore, our results from in situ experiments indicated that the microbial mats from South Shetland Islands could quickly accumulate (48 h) Hg when Hg dissolved salts were supplied. Over short-term periods, these mats do not transform Hg into MeHg under field conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Characterization of new microsatellite loci for population genetic studies in the Smooth Cauliflower Coral (Stylophora sp.)

    KAUST Repository

    Banguera-Hinestroza, E.

    2013-01-09

    A total of one hundred microsatellites loci were selected from the draft genome of Stylophora pistillata and evaluated in previously characterized samples of Stylophora cf pistillata from the Red Sea. 17 loci were amplified successfully and tested in 24 individuals from samples belonging to a single population from the central region of the Red Sea. The number of alleles ranged from 3 to 15 alleles per locus, while observed heterozygosity ranged from 0. 292 to 0. 95. Six of these loci showed significant deviations from Hardy-Weinberg equilibrium (HWE) expectations, and 4/136 paired loci comparisons suggested linkage disequilibrium after Bonferroni corrections. After excluding loci with significant HWE deviation and evidence of null alleles, average genetic diversity over loci in the population studied (N = 24, Nloci = 11) was 0. 701 ± 0. 380. This indicates that these loci can be used effectively to evaluate genetic diversity and undertake population genetics studies in Stylophora sp. populations. 2013 The Author(s).

  15. Unisexual reproduction in Huntiella moniliformis.

    Science.gov (United States)

    Wilson, A M; Godlonton, T; van der Nest, M A; Wilken, P M; Wingfield, M J; Wingfield, B D

    2015-07-01

    Sexual reproduction in fungi is controlled by genes present at the mating type (MAT) locus, which typically harbors transcription factors that influence the expression of many sex-related genes. The MAT locus exists as two alternative idiomorphs in ascomycetous fungi and sexual reproduction is initiated when genes from both idiomorphs are expressed. Thus, the gene content of this locus determines whether a fungus is heterothallic (self-sterile) or homothallic (self-fertile). Recently, a unique sub-class of homothallism has been described in fungi, where individuals possessing a single MAT idiomorph can reproduce sexually in the absence of a partner. Using various mycological, molecular and bioinformatic techniques, we investigated the sexual strategies and characterized the MAT loci in two tree wound-infecting fungi, Huntiella moniliformis and Huntiella omanensis. H. omanensis was shown to exhibit a typically heterothallic sexual reproductive cycle, with isolates possessing either the MAT1-1 or MAT1-2 idiomorph. This was in contrast to the homothallism via unisexual reproduction that was shown in H. moniliformis, where only the MAT1-2-1 gene was present in sexually reproducing cultures. While the evolutionary benefit and mechanisms underpinning a unisexual mating strategy remain unknown, it could have evolved to minimize the costs, while retaining the benefits, of normal sexual reproduction. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Nine Loci for Ocular Axial Length Identified through Genome-wide Association Studies, Including Shared Loci with Refractive Error

    Science.gov (United States)

    Cheng, Ching-Yu; Schache, Maria; Ikram, M. Kamran; Young, Terri L.; Guggenheim, Jeremy A.; Vitart, Veronique; MacGregor, Stuart; Verhoeven, Virginie J.M.; Barathi, Veluchamy A.; Liao, Jiemin; Hysi, Pirro G.; Bailey-Wilson, Joan E.; St. Pourcain, Beate; Kemp, John P.; McMahon, George; Timpson, Nicholas J.; Evans, David M.; Montgomery, Grant W.; Mishra, Aniket; Wang, Ya Xing; Wang, Jie Jin; Rochtchina, Elena; Polasek, Ozren; Wright, Alan F.; Amin, Najaf; van Leeuwen, Elisabeth M.; Wilson, James F.; Pennell, Craig E.; van Duijn, Cornelia M.; de Jong, Paulus T.V.M.; Vingerling, Johannes R.; Zhou, Xin; Chen, Peng; Li, Ruoying; Tay, Wan-Ting; Zheng, Yingfeng; Chew, Merwyn; Rahi, Jugnoo S.; Hysi, Pirro G.; Yoshimura, Nagahisa; Yamashiro, Kenji; Miyake, Masahiro; Delcourt, Cécile; Maubaret, Cecilia; Williams, Cathy; Guggenheim, Jeremy A.; Northstone, Kate; Ring, Susan M.; Davey-Smith, George; Craig, Jamie E.; Burdon, Kathryn P.; Fogarty, Rhys D.; Iyengar, Sudha K.; Igo, Robert P.; Chew, Emily; Janmahasathian, Sarayut; Iyengar, Sudha K.; Igo, Robert P.; Chew, Emily; Janmahasathian, Sarayut; Stambolian, Dwight; Wilson, Joan E. Bailey; MacGregor, Stuart; Lu, Yi; Jonas, Jost B.; Xu, Liang; Saw, Seang-Mei; Baird, Paul N.; Rochtchina, Elena; Mitchell, Paul; Wang, Jie Jin; Jonas, Jost B.; Nangia, Vinay; Hayward, Caroline; Wright, Alan F.; Vitart, Veronique; Polasek, Ozren; Campbell, Harry; Vitart, Veronique; Rudan, Igor; Vatavuk, Zoran; Vitart, Veronique; Paterson, Andrew D.; Hosseini, S. Mohsen; Iyengar, Sudha K.; Igo, Robert P.; Fondran, Jeremy R.; Young, Terri L.; Feng, Sheng; Verhoeven, Virginie J.M.; Klaver, Caroline C.; van Duijn, Cornelia M.; Metspalu, Andres; Haller, Toomas; Mihailov, Evelin; Pärssinen, Olavi; Wedenoja, Juho; Wilson, Joan E. Bailey; Wojciechowski, Robert; Baird, Paul N.; Schache, Maria; Pfeiffer, Norbert; Höhn, René; Pang, Chi Pui; Chen, Peng; Meitinger, Thomas; Oexle, Konrad; Wegner, Aharon; Yoshimura, Nagahisa; Yamashiro, Kenji; Miyake, Masahiro; Pärssinen, Olavi; Yip, Shea Ping; Ho, Daniel W.H.; Pirastu, Mario; Murgia, Federico; Portas, Laura; Biino, Genevra; Wilson, James F.; Fleck, Brian; Vitart, Veronique; Stambolian, Dwight; Wilson, Joan E. Bailey; Hewitt, Alex W.; Ang, Wei; Verhoeven, Virginie J.M.; Klaver, Caroline C.; van Duijn, Cornelia M.; Saw, Seang-Mei; Wong, Tien-Yin; Teo, Yik-Ying; Fan, Qiao; Cheng, Ching-Yu; Zhou, Xin; Ikram, M. Kamran; Saw, Seang-Mei; Teo, Yik-Ying; Fan, Qiao; Cheng, Ching-Yu; Zhou, Xin; Ikram, M. Kamran; Saw, Seang-Mei; Wong, Tien-Yin; Teo, Yik-Ying; Fan, Qiao; Cheng, Ching-Yu; Zhou, Xin; Ikram, M. Kamran; Saw, Seang-Mei; Wong, Tien-Yin; Teo, Yik-Ying; Fan, Qiao; Cheng, Ching-Yu; Zhou, Xin; Ikram, M. Kamran; Saw, Seang-Mei; Tai, E-Shyong; Teo, Yik-Ying; Fan, Qiao; Cheng, Ching-Yu; Zhou, Xin; Ikram, M. Kamran; Saw, Seang-Mei; Teo, Yik-Ying; Fan, Qiao; Cheng, Ching-Yu; Zhou, Xin; Ikram, M. Kamran; Mackey, David A.; MacGregor, Stuart; Hammond, Christopher J.; Hysi, Pirro G.; Deangelis, Margaret M.; Morrison, Margaux; Zhou, Xiangtian; Chen, Wei; Paterson, Andrew D.; Hosseini, S. Mohsen; Mizuki, Nobuhisa; Meguro, Akira; Lehtimäki, Terho; Mäkelä, Kari-Matti; Raitakari, Olli; Kähönen, Mika; Burdon, Kathryn P.; Craig, Jamie E.; Iyengar, Sudha K.; Igo, Robert P.; Lass, Jonathan H.; Reinhart, William; Belin, Michael W.; Schultze, Robert L.; Morason, Todd; Sugar, Alan; Mian, Shahzad; Soong, Hunson Kaz; Colby, Kathryn; Jurkunas, Ula; Yee, Richard; Vital, Mark; Alfonso, Eduardo; Karp, Carol; Lee, Yunhee; Yoo, Sonia; Hammersmith, Kristin; Cohen, Elisabeth; Laibson, Peter; Rapuano, Christopher; Ayres, Brandon; Croasdale, Christopher; Caudill, James; Patel, Sanjay; Baratz, Keith; Bourne, William; Maguire, Leo; Sugar, Joel; Tu, Elmer; Djalilian, Ali; Mootha, Vinod; McCulley, James; Bowman, Wayne; Cavanaugh, H. Dwight; Verity, Steven; Verdier, David; Renucci, Ann; Oliva, Matt; Rotkis, Walter; Hardten, David R.; Fahmy, Ahmad; Brown, Marlene; Reeves, Sherman; Davis, Elizabeth A.; Lindstrom, Richard; Hauswirth, Scott; Hamilton, Stephen; Lee, W. Barry; Price, Francis; Price, Marianne; Kelly, Kathleen; Peters, Faye; Shaughnessy, Michael; Steinemann, Thomas; Dupps, B.J.; Meisler, David M.; Mifflin, Mark; Olson, Randal; Aldave, Anthony; Holland, Gary; Mondino, Bartly J.; Rosenwasser, George; Gorovoy, Mark; Dunn, Steven P.; Heidemann, David G.; Terry, Mark; Shamie, Neda; Rosenfeld, Steven I.; Suedekum, Brandon; Hwang, David; Stone, Donald; Chodosh, James; Galentine, Paul G.; Bardenstein, David; Goddard, Katrina; Chin, Hemin; Mannis, Mark; Varma, Rohit; Borecki, Ingrid; Chew, Emily Y.; Haller, Toomas; Mihailov, Evelin; Metspalu, Andres; Wedenoja, Juho; Simpson, Claire L.; Wojciechowski, Robert; Höhn, René; Mirshahi, Alireza; Zeller, Tanja; Pfeiffer, Norbert; Lackner, Karl J.; Donnelly, Peter; Barroso, Ines; Blackwell, Jenefer M.; Bramon, Elvira; Brown, Matthew A.; Casas, Juan P.; Corvin, Aiden; Deloukas, Panos; Duncanson, Audrey; Jankowski, Janusz; Markus, Hugh S.; Mathew, Christopher G.; Palmer, Colin N.A.; Plomin, Robert; Rautanen, Anna; Sawcer, Stephen J.; Trembath, Richard C.; Viswanathan, Ananth C.; Wood, Nicholas W.; Spencer, Chris C.A.; Band, Gavin; Bellenguez, Céline; Freeman, Colin; Hellenthal, Garrett; Giannoulatou, Eleni; Pirinen, Matti; Pearson, Richard; Strange, Amy; Su, Zhan; Vukcevic, Damjan; Donnelly, Peter; Langford, Cordelia; Hunt, Sarah E.; Edkins, Sarah; Gwilliam, Rhian; Blackburn, Hannah; Bumpstead, Suzannah J.; Dronov, Serge; Gillman, Matthew; Gray, Emma; Hammond, Naomi; Jayakumar, Alagurevathi; McCann, Owen T.; Liddle, Jennifer; Potter, Simon C.; Ravindrarajah, Radhi; Ricketts, Michelle; Waller, Matthew; Weston, Paul; Widaa, Sara; Whittaker, Pamela; Barroso, Ines; Deloukas, Panos; Mathew, Christopher G.; Blackwell, Jenefer M.; Brown, Matthew A.; Corvin, Aiden; Spencer, Chris C.A.; Bettecken, Thomas; Meitinger, Thomas; Oexle, Konrad; Pirastu, Mario; Portas, Laura; Nag, Abhishek; Williams, Katie M.; Yonova-Doing, Ekaterina; Klein, Ronald; Klein, Barbara E.; Hosseini, S. Mohsen; Paterson, Andrew D.; Genuth, S.; Nathan, D.M.; Zinman, B.; Crofford, O.; Crandall, J.; Reid, M.; Brown-Friday, J.; Engel, S.; Sheindlin, J.; Martinez, H.; Shamoon, H.; Engel, H.; Phillips, M.; Gubitosi-Klug, R.; Mayer, L.; Pendegast, S.; Zegarra, H.; Miller, D.; Singerman, L.; Smith-Brewer, S.; Novak, M.; Quin, J.; Dahms, W.; Genuth, Saul; Palmert, M.; Brillon, D.; Lackaye, M.E.; Kiss, S.; Chan, R.; Reppucci, V.; Lee, T.; Heinemann, M.; Whitehouse, F.; Kruger, D.; Jones, J.K.; McLellan, M.; Carey, J.D.; Angus, E.; Thomas, A.; Galprin, A.; Bergenstal, R.; Johnson, M.; Spencer, M.; Morgan, K.; Etzwiler, D.; Kendall, D.; Aiello, Lloyd Paul; Golden, E.; Jacobson, A.; Beaser, R.; Ganda, O.; Hamdy, O.; Wolpert, H.; Sharuk, G.; Arrigg, P.; Schlossman, D.; Rosenzwieg, J.; Rand, L.; Nathan, D.M.; Larkin, M.; Ong, M.; Godine, J.; Cagliero, E.; Lou, P.; Folino, K.; Fritz, S.; Crowell, S.; Hansen, K.; Gauthier-Kelly, C.; Service, J.; Ziegler, G.; Luttrell, L.; Caulder, S.; Lopes-Virella, M.; Colwell, J.; Soule, J.; Fernandes, J.; Hermayer, K.; Kwon, S.; Brabham, M.; Blevins, A.; Parker, J.; Lee, D.; Patel, N.; Pittman, C.; Lindsey, P.; Bracey, M.; Lee, K.; Nutaitis, M.; Farr, A.; Elsing, S.; Thompson, T.; Selby, J.; Lyons, T.; Yacoub-Wasef, S.; Szpiech, M.; Wood, D.; Mayfield, R.; Molitch, M.; Schaefer, B.; Jampol, L.; Lyon, A.; Gill, M.; Strugula, Z.; Kaminski, L.; Mirza, R.; Simjanoski, E.; Ryan, D.; Kolterman, O.; Lorenzi, G.; Goldbaum, M.; Sivitz, W.; Bayless, M.; Counts, D.; Johnsonbaugh, S.; Hebdon, M.; Salemi, P.; Liss, R.; Donner, T.; Gordon, J.; Hemady, R.; Kowarski, A.; Ostrowski, D.; Steidl, S.; Jones, B.; Herman, W.H.; Martin, C.L.; Pop-Busui, R.; Sarma, A.; Albers, J.; Feldman, E.; Kim, K.; Elner, S.; Comer, G.; Gardner, T.; Hackel, R.; Prusak, R.; Goings, L.; Smith, A.; Gothrup, J.; Titus, P.; Lee, J.; Brandle, M.; Prosser, L.; Greene, D.A.; Stevens, M.J.; Vine, A.K.; Bantle, J.; Wimmergren, N.; Cochrane, A.; Olsen, T.; Steuer, E.; Rath, P.; Rogness, B.; Hainsworth, D.; Goldstein, D.; Hitt, S.; Giangiacomo, J.; Schade, D.S.; Canady, J.L.; Chapin, J.E.; Ketai, L.H.; Braunstein, C.S.; Bourne, P.A.; Schwartz, S.; Brucker, A.; Maschak-Carey, B.J.; Baker, L.; Orchard, T.; Silvers, N.; Ryan, C.; Songer, T.; Doft, B.; Olson, S.; Bergren, R.L.; Lobes, L.; Rath, P. Paczan; Becker, D.; Rubinstein, D.; Conrad, P.W.; Yalamanchi, S.; Drash, A.; Morrison, A.; Bernal, M.L.; Vaccaro-Kish, J.; Malone, J.; Pavan, P.R.; Grove, N.; Iyer, M.N.; Burrows, A.F.; Tanaka, E.A.; Gstalder, R.; Dagogo-Jack, S.; Wigley, C.; Ricks, H.; Kitabchi, A.; Murphy, M.B.; Moser, S.; Meyer, D.; Iannacone, A.; Chaum, E.; Yoser, S.; Bryer-Ash, M.; Schussler, S.; Lambeth, H.; Raskin, P.; Strowig, S.; Zinman, B.; Barnie, A.; Devenyi, R.; Mandelcorn, M.; Brent, M.; Rogers, S.; Gordon, A.; Palmer, J.; Catton, S.; Brunzell, J.; Wessells, H.; de Boer, I.H.; Hokanson, J.; Purnell, J.; Ginsberg, J.; Kinyoun, J.; Deeb, S.; Weiss, M.; Meekins, G.; Distad, J.; Van Ottingham, L.; Dupre, J.; Harth, J.; Nicolle, D.; Driscoll, M.; Mahon, J.; Canny, C.; May, M.; Lipps, J.; Agarwal, A.; Adkins, T.; Survant, L.; Pate, R.L.; Munn, G.E.; Lorenz, R.; Feman, S.; White, N.; Levandoski, L.; Boniuk, I.; Grand, G.; Thomas, M.; Joseph, D.D.; Blinder, K.; Shah, G.; Boniuk; Burgess; Santiago, J.; Tamborlane, W.; Gatcomb, P.; Stoessel, K.; Taylor, K.; Goldstein, J.; Novella, S.; Mojibian, H.; Cornfeld, D.; Lima, J.; Bluemke, D.; Turkbey, E.; van der Geest, R.J.; Liu, C.; Malayeri, A.; Jain, A.; Miao, C.; Chahal, H.; Jarboe, R.; Maynard, J.; Gubitosi-Klug, R.; Quin, J.; Gaston, P.; Palmert, M.; Trail, R.; Dahms, W.; Lachin, J.; Cleary, P.; Backlund, J.; Sun, W.; Braffett, B.; Klumpp, K.; Chan, K.; Diminick, L.; Rosenberg, D.; Petty, B.; Determan, A.; Kenny, D.; Rutledge, B.; Younes, Naji; Dews, L.; Hawkins, M.; Cowie, C.; Fradkin, J.; Siebert, C.; Eastman, R.; Danis, R.; Gangaputra, S.; Neill, S.; Davis, M.; Hubbard, L.; Wabers, H.; Burger, M.; Dingledine, J.; Gama, V.; Sussman, R.; Steffes, M.; Bucksa, J.; Nowicki, M.; Chavers, B.; O’Leary, D.; Polak, J.; Harrington, A.; Funk, L.; Crow, R.; Gloeb, B.; Thomas, S.; O’Donnell, C.; Soliman, E.; Zhang, Z.M.; Prineas, R.; Campbell, C.; Ryan, C.; Sandstrom, D.; Williams, T.; Geckle, M.; Cupelli, E.; Thoma, F.; Burzuk, B.; Woodfill, T.; Low, P.; Sommer, C.; Nickander, K.; Budoff, M.; Detrano, R.; Wong, N.; Fox, M.; Kim, L.; Oudiz, R.; Weir, G.; Espeland, M.; Manolio, T.; Rand, L.; Singer, D.; Stern, M.; Boulton, A.E.; Clark, C.; D’Agostino, R.; Lopes-Virella, M.; Garvey, W.T.; Lyons, T.J.; Jenkins, A.; Virella, G.; Jaffa, A.; Carter, Rickey; Lackland, D.; Brabham, M.; McGee, D.; Zheng, D.; Mayfield, R.K.; Boright, A.; Bull, S.; Sun, L.; Scherer, S.; Zinman, B.; Natarajan, R.; Miao, F.; Zhang, L.; Chen;, Z.; Nathan, D.M.; Makela, Kari-Matti; Lehtimaki, Terho; Kahonen, Mika; Raitakari, Olli; Yoshimura, Nagahisa; Matsuda, Fumihiko; Chen, Li Jia; Pang, Chi Pui; Yip, Shea Ping; Yap, Maurice K.H.; Meguro, Akira; Mizuki, Nobuhisa; Inoko, Hidetoshi; Foster, Paul J.; Zhao, Jing Hua; Vithana, Eranga; Tai, E-Shyong; Fan, Qiao; Xu, Liang; Campbell, Harry; Fleck, Brian; Rudan, Igor; Aung, Tin; Hofman, Albert; Uitterlinden, André G.; Bencic, Goran; Khor, Chiea-Chuen; Forward, Hannah; Pärssinen, Olavi; Mitchell, Paul; Rivadeneira, Fernando; Hewitt, Alex W.; Williams, Cathy; Oostra, Ben A.; Teo, Yik-Ying; Hammond, Christopher J.; Stambolian, Dwight; Mackey, David A.; Klaver, Caroline C.W.; Wong, Tien-Yin; Saw, Seang-Mei; Baird, Paul N.

    2013-01-01

    Refractive errors are common eye disorders of public health importance worldwide. Ocular axial length (AL) is the major determinant of refraction and thus of myopia and hyperopia. We conducted a meta-analysis of genome-wide association studies for AL, combining 12,531 Europeans and 8,216 Asians. We identified eight genome-wide significant loci for AL (RSPO1, C3orf26, LAMA2, GJD2, ZNRF3, CD55, MIP, and ALPPL2) and confirmed one previously reported AL locus (ZC3H11B). Of the nine loci, five (LAMA2, GJD2, CD55, ALPPL2, and ZC3H11B) were associated with refraction in 18 independent cohorts (n = 23,591). Differential gene expression was observed for these loci in minus-lens-induced myopia mouse experiments and human ocular tissues. Two of the AL genes, RSPO1 and ZNRF3, are involved in Wnt signaling, a pathway playing a major role in the regulation of eyeball size. This study provides evidence of shared genes between AL and refraction, but importantly also suggests that these traits may have unique pathways. PMID:24144296

  17. 49 CFR 393.108 - How is the working load limit of a tiedown, or the load restraining value of a friction mat...

    Science.gov (United States)

    2010-10-01

    ... load restraining value of a friction mat, determined? 393.108 Section 393.108 Transportation Other... load restraining value of a friction mat, determined? (a) The working load limit (WLL) of a tiedown... load limits. (g) Friction mats which are not marked or rated by the manufacturer shall be considered to...

  18. Mapping of four distinct BCR-related loci to chromosome region 22q11: order of BCR loci relative to chronic myelogenous leukemia and acute lymphoblastic leukemia breakpoints

    International Nuclear Information System (INIS)

    Croce, C.M.; Huebner, K.; Isobe, M.; Fainstain, E.; Lifshitz, B.; Shtivelman, E.; Canaani, E.

    1987-01-01

    A probe derived from the 3' region of the BCR gene (breakpoint cluster region gene) detects four distinct loci in the human genome. One of the loci corresponds to the complete BCR gene, whereas the other contain a 3' segment of the gene. After HindIII cleavage of human DNA, these four loci are detected as 23-, 19-, 13-, and 9-kikobase-pair fragments, designated BCR4, BCR3, BCR2, and BCR1, respectively, with BCR1 deriving from the original complete BCR gene. All four BCR loci segregate 100% concordantly with human chromosome 22 in a rodent-human somatic cell hybrid panel and are located at chromosome region 22q11.2 by chromosomal in situ hybridization. The BCR2 and BCR4 loci are amplified in leukemia cell line K562 cells, indicating that they fall within the amplification unit that includes immunoglobulin λ light chain locus (IGL) and ABL locus on the K562 Philadelphia chromosome (Ph 1 ). Similarly, in mouse-human hybrids retaining a Ph 1 chromosome derived from an acute lymphoblastic leukemia-in the absence of the 9q + and 22, only BCR2 and BCR4 loci are retained. Thus, the order of loci on chromosome 22 is centromere → BCR2, BCR4, and IGL → BCR1 → BCR3 → SIS, possibly eliminating BCR2 and BCR4 loci as candidate targets for juxtaposition to the ABL gene in the acute lymphoblastic leukemia Ph 1 chromosome

  19. Phylogenetic Evidence for the Existence of Novel Thermophilic Bacteria in Hot Spring Sulfur-Turf Microbial Mats in Japan

    Science.gov (United States)

    Yamamoto, Hiroyuki; Hiraishi, Akira; Kato, Kenji; Chiura, Hiroshi X.; Maki, Yonosuke; Shimizu, Akira

    1998-01-01

    So-called sulfur-turf microbial mats, which are macroscopic white filaments or bundles consisting of large sausage-shaped bacteria and elemental sulfur particles, occur in sulfide-containing hot springs in Japan. However, no thermophiles from sulfur-turf mats have yet been isolated as cultivable strains. This study was undertaken to determine the phylogenetic positions of the sausage-shaped bacteria in sulfur-turf mats by direct cloning and sequencing of 16S rRNA genes amplified from the bulk DNAs of the mats. Common clones with 16S rDNA sequences with similarity levels of 94.8 to 99% were isolated from sulfur-turf mat samples from two geographically remote hot springs. Phylogenetic analysis showed that the phylotypes of the common clones formed a major cluster with members of the Aquifex-Hydrogenobacter complex, which represents the most deeply branching lineage of the domain bacteria. Furthermore, the bacteria of the sulfur-turf mat phylotypes formed a clade distinguishable from that of other members of the Aquifex-Hydrogenobacter complex at the order or subclass level. In situ hybridization with clone-specific probes for 16S rRNA revealed that the common phylotype of sulfur-turf mat bacteria is that of the predominant sausage-shaped bacteria. PMID:9572936

  20. Dynamics of bacterial populations during bench-scale bioremediation of oily seawater and desert soil bioaugmented with coastal microbial mats.

    Science.gov (United States)

    Ali, Nidaa; Dashti, Narjes; Salamah, Samar; Sorkhoh, Naser; Al-Awadhi, Husain; Radwan, Samir

    2016-03-01

    This study describes a bench-scale attempt to bioremediate Kuwaiti, oily water and soil samples through bioaugmentation with coastal microbial mats rich in hydrocarbonoclastic bacterioflora. Seawater and desert soil samples were artificially polluted with 1% weathered oil, and bioaugmented with microbial mat suspensions. Oil removal and microbial community dynamics were monitored. In batch cultures, oil removal was more effective in soil than in seawater. Hydrocarbonoclastic bacteria associated with mat samples colonized soil more readily than seawater. The predominant oil degrading bacterium in seawater batches was the autochthonous seawater species Marinobacter hydrocarbonoclasticus. The main oil degraders in the inoculated soil samples, on the other hand, were a mixture of the autochthonous mat and desert soil bacteria; Xanthobacter tagetidis, Pseudomonas geniculata, Olivibacter ginsengisoli and others. More bacterial diversity prevailed in seawater during continuous than batch bioremediation. Out of seven hydrocarbonoclastic bacterial species isolated from those cultures, only one, Mycobacterium chlorophenolicum, was of mat origin. This result too confirms that most of the autochthonous mat bacteria failed to colonize seawater. Also culture-independent analysis of seawater from continuous cultures revealed high-bacterial diversity. Many of the bacteria belonged to the Alphaproteobacteria, Flavobacteria and Gammaproteobacteria, and were hydrocarbonoclastic. Optimal biostimulation practices for continuous culture bioremediation of seawater via mat bioaugmentation were adding the highest possible oil concentration as one lot in the beginning of bioremediation, addition of vitamins, and slowing down the seawater flow rate. © 2016 The Author. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  1. Nanofiber mat spinal cord dressing-released glutamate impairs blood-spinal cord barrier

    Directory of Open Access Journals (Sweden)

    Dorota Sulejczak

    2016-12-01

    Full Text Available An excessive glutamate level can result in excitotoxic damage and death of central nervous system (CNS cells, and is involved in the pathogenesis of many CNS diseases. It may also be related to a failure of the blood-spinal cord barrier (BSCB. This study was aimed at examining the effects of extended administration of monosodium glutamate on the BSCB and spinal cord cells in adult male Wistar rats. The glutamate was delivered by subarachnoidal application of glutamate-carrying electrospun nanofiber mat dressing at the lumbar enlargement level. Half of the rats with the glutamate-loaded mat application were treated systemically with the histone deacetylase inhibitor valproic acid. A group of intact rats and a rat group with subarachnoidal application of an ‘empty’ (i.e., carrying no glutamate nanofiber mat dressing served as controls. All the rats were euthanized three weeks later and lumbar fragments of their spinal cords were harvested for histological, immunohistochemical and ultrastructural studies. The samples from controls revealed normal parenchyma and BSCB morphology, whereas those from rats with the glutamate-loaded nanofiber mat dressing showed many intraparenchymal microhemorrhages of variable sizes. The capillaries in the vicinity of the glutamate-carrying dressing (in the meninges and white matter alike were edematous and leaky, and their endothelial cells showed degenerative changes: extensive swelling, enhanced vacuo­lization and the presence of vascular intraluminal projections. However, endothelial tight junctions were generally well preserved. Some endothelial cells were dying by necrosis or apoptosis. The adjacent parenchyma showed astrogliosis with astrocytic hypertrophy and swelling of perivascular astrocytic feet. Neurons in the parenchyma revealed multiple symptoms of degeneration, including, inter alia, perikaryal, dendritic and axonal swelling, and destruction of organelles. All the damage symptoms were slightly less

  2. An investigation of electrospun Henna leaves extract-loaded chitosan based nanofibrous mats for skin tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Yousefi, Iman, E-mail: iman_yousefi@ut.ac.ir [School of Chemical Engineering, College of Engineering, University of Tehran, Tehran (Iran, Islamic Republic of); Medical Biomaterials Research Center (MBRC), Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Pakravan, Mehdi [Department of Chemical Engineering, Ecole Polytechnique de Montreal, Montreal, Quebec (Canada); Rahimi, Hoda [Department of Pharmacognosy, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Bahador, Abbas; Farshadzadeh, Zahra [Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Haririan, Ismael, E-mail: haririan@tums.ac.ir [Medical Biomaterials Research Center (MBRC), Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Department of Pharmaceutical Biomaterial, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Department of Pharmaceutics, School of Pharmacy, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2017-06-01

    Wound healing characteristics of some plant extracts have been well known for many years, and they have been utilized for such applications in traditional way. Recently electrospun nanofibrous mats showed promising properties for tissue engineering and especially for skin repair. It is expected that incorporation of plant extracts into such structures could provide higher performance and synergistic effect for biomedical and wound healing applications. The final purpose of this study is to fabricate chitosan based nanofiber mats loaded with a traditional plant extract of Lawsonia inermis (Henna) leaves to enhance the antibacterial efficacy and wound healing of the precursor nanofibers. The morphology, structure, mechanical properties and swelling and weight loss degree of the electrospun nanofibers have been investigated in this study. Antibacterial activity, cell biocompatibility evaluations and in vivo wound healing activity of the abovementioned mats were also studied. The FESEM images of Henna leaves extract-loaded nanofibers proved that homogeneous, smooth and defect free nanofibers of 64–87 nm in diameter have been prepared. Presence of Henna extract in the electrospun fibers was approved by Fourier Transform Infrared spectroscopy. Incorporation of Henna extract into the nanofiber mats exhibited significant synergistic antibacterial activity against bacterial cells. It was well supported by the results of cell viability and proliferation of human foreskin fibroblast cells on the prepared scaffolds. Therefore, the results of this work showed that Henna leaves extract incorporated chitosan nonwoven mats have a great potential to be used as the biodegradable, biobased and antibacterial wound healing dressings. - Highlights: • Henna leaves extract were successfully loaded into chitosan based nanofiber mats. • These mats demonstrated significant synergistic antibacterial activity. • Combined properties of chitosan nanofibers and Henna promoted cell

  3. An investigation of electrospun Henna leaves extract-loaded chitosan based nanofibrous mats for skin tissue engineering

    International Nuclear Information System (INIS)

    Yousefi, Iman; Pakravan, Mehdi; Rahimi, Hoda; Bahador, Abbas; Farshadzadeh, Zahra; Haririan, Ismael

    2017-01-01

    Wound healing characteristics of some plant extracts have been well known for many years, and they have been utilized for such applications in traditional way. Recently electrospun nanofibrous mats showed promising properties for tissue engineering and especially for skin repair. It is expected that incorporation of plant extracts into such structures could provide higher performance and synergistic effect for biomedical and wound healing applications. The final purpose of this study is to fabricate chitosan based nanofiber mats loaded with a traditional plant extract of Lawsonia inermis (Henna) leaves to enhance the antibacterial efficacy and wound healing of the precursor nanofibers. The morphology, structure, mechanical properties and swelling and weight loss degree of the electrospun nanofibers have been investigated in this study. Antibacterial activity, cell biocompatibility evaluations and in vivo wound healing activity of the abovementioned mats were also studied. The FESEM images of Henna leaves extract-loaded nanofibers proved that homogeneous, smooth and defect free nanofibers of 64–87 nm in diameter have been prepared. Presence of Henna extract in the electrospun fibers was approved by Fourier Transform Infrared spectroscopy. Incorporation of Henna extract into the nanofiber mats exhibited significant synergistic antibacterial activity against bacterial cells. It was well supported by the results of cell viability and proliferation of human foreskin fibroblast cells on the prepared scaffolds. Therefore, the results of this work showed that Henna leaves extract incorporated chitosan nonwoven mats have a great potential to be used as the biodegradable, biobased and antibacterial wound healing dressings. - Highlights: • Henna leaves extract were successfully loaded into chitosan based nanofiber mats. • These mats demonstrated significant synergistic antibacterial activity. • Combined properties of chitosan nanofibers and Henna promoted cell

  4. Environmental status of algal mat sites located at the east coast of Saudi Arabia following the Gulf War

    International Nuclear Information System (INIS)

    Al-Thukair, A.

    1993-01-01

    Remote sensing techniques and ground truth verification were used to provide information on algal mat locations and damage intensity caused by the oil spill. Pre and post oil spill satellite images, ground truth assessment were compared for damage evaluation. Locations and sites status (heavily oiled, recovering, and no algal mats) were conveyed in maps. Recovered sites are found in Abu Ali and Tanajib areas. However, recovery seems to be slower in Abu Ali area as compared to Tanajib. Different types and formations of algal mats were found in both areas. This differentiation is more likely to be attributable to coastal topography and tide regimes

  5. Large red cyanobacterial mats (Spirulina subsalsa Oersted ex Gomont in the shallow sublittoral of the southern Baltic

    Directory of Open Access Journals (Sweden)

    Piotr Balazy

    2014-06-01

    Full Text Available We report the first observation of large red cyanobacterial mats in the southern Baltic Sea. The mats (up to 2.5 m in diameter were observed by SCUBA divers at 7.7 m depth on loamy sediments in the Gulf of Gdańsk in mid-November 2013. The main structure of the mat was formed by cyanobacteria Spirulina subsalsa Oersted ex Gomont; a number of other cyanobacteria, diatoms and nematode species were also present. After a few days in the laboratory, the red trichomes of S. subsalsa started to turn blue-green in colour, suggesting the strong chromatic acclimation abilities of this species.

  6. Full-Scale Evaluation of DuraDeck (registered trademark) and MegaDeck (trademark) Matting Systems

    Science.gov (United States)

    2013-07-01

    plates studded with threaded bolts were placed ERDC/GSL TR-13-27 10 underneath two pre-drilled corners of the panel. The plates were positioned so...metal plates studded with threaded ERDC/GSL TR-13-27 4 Figure 1. DuraDeck® mat panel, top surface. Figure 2. DuraDeck® mat panel, bottom surface...ERDC/GSL TR-13-27 5 bolts , as shown in Figure 3, underneath the mat corners and then installing special connector nuts from the top surface

  7. Characterization and Exploitation of CRISPR Loci in Bifidobacterium longum

    Directory of Open Access Journals (Sweden)

    Claudio Hidalgo-Cantabrana

    2017-09-01

    Full Text Available Diverse CRISPR-Cas systems provide adaptive immunity in many bacteria and most archaea, via a DNA-encoded, RNA-mediated, nucleic-acid targeting mechanism. Over time, CRISPR loci expand via iterative uptake of invasive DNA sequences into the CRISPR array during the adaptation process. These genetic vaccination cards thus provide insights into the exposure of strains to phages and plasmids in space and time, revealing the historical predatory exposure of a strain. These genetic loci thus constitute a unique basis for genotyping of strains, with potential of resolution at the strain-level. Here, we investigate the occurrence and diversity of CRISPR-Cas systems in the genomes of various Bifidobacterium longum strains across three sub-species. Specifically, we analyzed the genomic content of 66 genomes belonging to B. longum subsp. longum, B. longum subsp. infantis and B. longum subsp. suis, and identified 25 strains that carry 29 total CRISPR-Cas systems. We identify various Type I and Type II CRISPR-Cas systems that are widespread in this species, notably I-C, I-E, and II-C. Noteworthy, Type I-C systems showed extended CRISPR arrays, with extensive spacer diversity. We show how these hypervariable loci can be used to gain insights into strain origin, evolution and phylogeny, and can provide discriminatory sequences to distinguish even clonal isolates. By investigating CRISPR spacer sequences, we reveal their origin and implicate phages and prophages as drivers of CRISPR immunity expansion in this species, with redundant targeting of select prophages. Analysis of CRISPR spacer origin also revealed novel PAM sequences. Our results suggest that CRISPR-Cas immune systems are instrumental in mounting diversified viral resistance in B. longum, and show that these sequences are useful for typing across three subspecies.

  8. Positive Selection on Loci Associated with Drug and Alcohol Dependence.

    Directory of Open Access Journals (Sweden)

    Brooke Sadler

    Full Text Available Much of the evolution of human behavior remains a mystery, including how certain disadvantageous behaviors are so prevalent. Nicotine addiction is one such phenotype. Several loci have been implicated in nicotine related phenotypes including the nicotinic receptor gene clusters (CHRNs on chromosomes 8 and 15. Here we use 1000 Genomes sequence data from 3 populations (Africans, Asians and Europeans to examine whether natural selection has occurred at these loci. We used Tajima's D and the integrated haplotype score (iHS to test for evidence of natural selection. Our results provide evidence for strong selection in the nicotinic receptor gene cluster on chromosome 8, previously found to be significantly associated with both nicotine and cocaine dependence, as well as evidence selection acting on the region containing the CHRNA5 nicotinic receptor gene on chromosome 15, that is genome wide significant for risk for nicotine dependence. To examine the possibility that this selection is related to memory and learning, we utilized genetic data from the Collaborative Studies on the Genetics of Alcoholism (COGA to test variants within these regions with three tests of memory and learning, the Wechsler Adult Intelligence Scale (WAIS Block Design, WAIS Digit Symbol and WAIS Information tests. Of the 17 SNPs genotyped in COGA in this region, we find one significantly associated with WAIS digit symbol test results. This test captures aspects of reaction time and memory, suggesting that a phenotype relating to memory and learning may have been the driving force behind selection at these loci. This study could begin to explain why these seemingly deleterious SNPs are present at their current frequencies.

  9. Surface modification and micromechanical properties of jute fiber mat reinforced polypropylene composites

    Directory of Open Access Journals (Sweden)

    2007-05-01

    Full Text Available A new treating method using sodium hydroxide (NaOH and Maleic anhydride-grafted polypropylene (MPP emulsion was introduced to treat jute fiber mat in order to enhance the performance of jute/polypropylene (PP composite prepared by film stacking method. The surface modifications of jute fiber mat have been found to be very effective in improving the fiber-matrix adhesion. It was shown that treatments changed not only the surface topography but also the distribution of diameter and strength for the jute fibers, which was analyzed by using a two-parameter Weibull distribution model. Consequently, the interfacial shear strength, flexural and tensile strength of the composites all increased, but the impact strength decreased slightly. These results have demonstrated a new approach to use natural materials to enhance the mechanical performances of composites.

  10. Productivity and species composition of algal mat communities exposed to a fluctuating thermal regime

    International Nuclear Information System (INIS)

    Tison, D.L.; Wilde, E.W.; Pope, D.H.; Fliermans, C.B.

    1981-01-01

    Algal mat communities growing in thermal effluents of production nuclear reactors at the Savannah River Plant, near Aiken, SC, are exposed to large temperature fluctuations resulting from reactor operations. Rates of primary production and species composition were monitored at 4 sites along a thermal gradient in a trough microcosm to determine how these large temperature fluctuations affected productivity and algal community structure. Blue-green algae (cyanobacteria) were the only phototrophic primary producers growing in water above 45 0 C. These thermophiles were able to survive and apparently adapt to ambient temperatures when the reactor was shut down. The algal mat communities exposed to 14 C-labeled dissolved organic compounds and a decrease in primary production were observed during periods of thermal fluctuation. The results show that the dominant phototrophs in this artificially heated aquatic habitat have been selected for their abiity to survive large temperature fluctuations and are similar to those of natural hot springs

  11. Mobilifilum chasei: morphology and ecology of a spirochete from an intertidal stratified microbial mat community

    Science.gov (United States)

    Margulis, L.; Hinkle, G.; Stolz, J.; Craft, F.; Esteve, I.; Guerrero, R.

    1990-01-01

    Spirochetes were found in the lower anoxiphototrophic layer of a stratified microbial mat (North Pond, Laguna Figueroa, Baja California, Mexico). Ultra-structural analysis of thin sections of field samples revealed spirochetes approximately 0.25 micrometer in diameter with 10 or more periplasmic flagella, leading to the interpretation that these spirochetes bear 10 flagellar insertions on each end. Morphometric study showed these free-living spirochetes greatly resemble certain symbiotic ones, i.e., Borrelia and certain termite spirochetes, the transverse sections of which are presented here. The ultrastructure of this spirochete also resembles Hollandina and Diplocalyx (spirochetes symbiotic in arthropods) more than it does Spirochaeta, the well known genus of mud-dwelling spirochetes. The new spirochete was detected in mat material collected both in 1985 and in 1987. Unique morphology (i.e., conspicuous outer coat of inner membrane, large number of periplasmic flagella) and ecology prompt us to name a new free-living spirochete.

  12. Living Dendrolitic Microbial Mats in Hamelin Pool, Shark Bay, Western Australia

    Directory of Open Access Journals (Sweden)

    Erica P. Suosaari

    2018-06-01

    Full Text Available Hamelin Pool, Shark Bay, Western Australia, is home to the largest and most diverse assemblage of living marine stromatolites, with shapes and sizes comparable to ancient structures. A recent field-intensive program revealed seasonally ephemeral occurrences of modern dendrolitic microbial mats forming in intertidal, low energy settings. Dominated by filamentous cyanobacteria, dendrolitic microbial mats are formed when filaments provide a supporting framework as a result of gliding mobility, to build a shrubby morphology. Dendrolites, known throughout the rock record, refer to macroscopic microbialites with mesostuctures composed of unlaminated arborescent structures called shrubs. In these modern examples, thick filaments of Lyngbya aestuarii form the “trunk” of the bush, with finer filaments of Lyngbya fragilis, Phormidium sp. and Schizothrix sp. forming the “branches” These biologically-influenced dendrolitic structures provide insight into the complex interplay of microbial communities and the environment, broadening our understanding of shrub and dendrolite formation throughout the rock record.

  13. Flavours – det smakar doft : Upplevelsen av mat och vin i kombination

    OpenAIRE

    Hult, Jonas; Lagnetoft, David; Nygren, Nadia

    2011-01-01

    Inledning: Den vetenskapliga förankringen om mat och vin i kombination är låg. Upplevelsenav en måltid involverar alla de mänskliga sinnena, vilket således har gjort den svår att mäta.Hur stor roll spelar egentligen grundsmakerna och krävs det ytterligare element för att lyfta enkombination av mat och vin till högre höjder?Bakgrund: Förutom smaklökarna på tungan som bildar den grundläggande uppfattningen avdet vi stoppar i munnen, är det främst munkänsla och flavours som bidrar till helheten ...

  14. Out-of-plane ultimate shear strength of RC mat-slab foundations

    International Nuclear Information System (INIS)

    Kumagai, Hitoshi; Nukui, Yasushi; Imamura, Akira; Terayama, Takeshi; Hagiwara, Tetsuya; Kojima, Isao

    2011-01-01

    There have been few studies on the out-of-plane shear in RC mat-slab foundations, and the reasonable method has been demanded to estimate ultimate shear strength of RC mat-slab foundations in the nuclear facilities. In the previous study, the out-of-plane loading tests on the 20 square slab specimens had been performed to collect the fundamental data. In this study, the test results were successfully predicted by 3D non-linear Finite Element Analysis. It has been confirmed that the ultimate shear stress in the slab specimen can be estimated by the Arakawa's formula, which is commonly used to estimate the shear strength of RC beams. (author)

  15. Association analysis identifies 65 new breast cancer risk loci

    OpenAIRE

    Michailidou, Kyriaki; Lindström, Sara; Dennis, Joe; Beesley, Jonathan; Hui, Shirley; Kar, Siddhartha; Lemaçon, Audrey; Soucy, Penny; Glubb, Dylan; Rostamianfar, Asha; Bolla, Manjeet K; Wang, Qin; Tyrer, Jonathan; Dicks, Ed; Lee, Andrew

    2017-01-01

    Breast cancer risk is influenced by rare coding variants in susceptibility genes, such as BRCA1, and many common, mostly non-coding variants. However, much of the genetic contribution to breast cancer risk remains unknown. Here we report the results of a genome-wide association study of breast cancer in 122,977 cases and 105,974 controls of European ancestry and 14,068 cases and 13,104 controls of East Asian ancestry. We identified 65 new loci that are associated with overall breast cancer ri...

  16. Mapping autism risk loci using genetic linkage and chromosomal rearrangements

    Science.gov (United States)

    Szatmari, Peter; Paterson, Andrew; Zwaigenbaum, Lonnie; Roberts, Wendy; Brian, Jessica; Liu, Xiao-Qing; Vincent, John; Skaug, Jennifer; Thompson, Ann; Senman, Lili; Feuk, Lars; Qian, Cheng; Bryson, Susan; Jones, Marshall; Marshall, Christian; Scherer, Stephen; Vieland, Veronica; Bartlett, Christopher; Mangin, La Vonne; Goedken, Rhinda; Segre, Alberto; Pericak-Vance, Margaret; Cuccaro, Michael; Gilbert, John; Wright, Harry; Abramson, Ruth; Betancur, Catalina; Bourgeron, Thomas; Gillberg, Christopher; Leboyer, Marion; Buxbaum, Joseph; Davis, Kenneth; Hollander, Eric; Silverman, Jeremy; Hallmayer, Joachim; Lotspeich, Linda; Sutcliffe, James; Haines, Jonathan; Folstein, Susan; Piven, Joseph; Wassink, Thomas; Sheffield, Val; Geschwind, Daniel; Bucan, Maja; Brown, Ted; Cantor, Rita; Constantino, John; Gilliam, Conrad; Herbert, Martha; Lajonchere, Clara; Ledbetter, David; Lese-Martin, Christa; Miller, Janet; Nelson, Stan; Samango-Sprouse, Carol; Spence, Sarah; State, Matthew; Tanzi, Rudolph; Coon, Hilary; Dawson, Geraldine; Devlin, Bernie; Estes, Annette; Flodman, Pamela; Klei, Lambertus; Mcmahon, William; Minshew, Nancy; Munson, Jeff; Korvatska, Elena; Rodier, Patricia; Schellenberg, Gerard; Smith, Moyra; Spence, Anne; Stodgell, Chris; Tepper, Ping Guo; Wijsman, Ellen; Yu, Chang-En; Rogé, Bernadette; Mantoulan, Carine; Wittemeyer, Kerstin; Poustka, Annemarie; Felder, Bärbel; Klauck, Sabine; Schuster, Claudia; Poustka, Fritz; Bölte, Sven; Feineis-Matthews, Sabine; Herbrecht, Evelyn; Schmötzer, Gabi; Tsiantis, John; Papanikolaou, Katerina; Maestrini, Elena; Bacchelli, Elena; Blasi, Francesca; Carone, Simona; Toma, Claudio; Van Engeland, Herman; De Jonge, Maretha; Kemner, Chantal; Koop, Frederieke; Langemeijer, Marjolein; Hijmans, Channa; Staal, Wouter; Baird, Gillian; Bolton, Patrick; Rutter, Michael; Weisblatt, Emma; Green, Jonathan; Aldred, Catherine; Wilkinson, Julie-Anne; Pickles, Andrew; Le Couteur, Ann; Berney, Tom; Mcconachie, Helen; Bailey, Anthony; Francis, Kostas; Honeyman, Gemma; Hutchinson, Aislinn; Parr, Jeremy; Wallace, Simon; Monaco, Anthony; Barnby, Gabrielle; Kobayashi, Kazuhiro; Lamb, Janine; Sousa, Ines; Sykes, Nuala; Cook, Edwin; Guter, Stephen; Leventhal, Bennett; Salt, Jeff; Lord, Catherine; Corsello, Christina; Hus, Vanessa; Weeks, Daniel; Volkmar, Fred; Tauber, Maïté; Fombonne, Eric; Shih, Andy; Meyer, Kacie

    2007-01-01

    Autism spectrum disorders (ASD) are common, heritable neurodevelopmental conditions. The genetic architecture of ASD is complex, requiring large samples to overcome heterogeneity. Here we broaden coverage and sample size relative to other studies of ASD by using Affymetrix 10K single nucleotide polymorphism (SNP) arrays and 1168 families with ≥ 2 affected individuals to perform the largest linkage scan to date, while also analyzing copy number variation (CNV) in these families. Linkage and CNV analyses implicate chromosome 11p12-p13 and neurexins, respectively, amongst other candidate loci. Neurexins team with previously-implicated neuroligins for glutamatergic synaptogenesis, highlighting glutamate-related genes as promising candidates for ASD. PMID:17322880

  17. Thirteen nuclear microsatellite loci for butternut (Juglans cinerea L.).

    Science.gov (United States)

    Hoban, Sean; Anderson, Robert; McCleary, Tim; Schlarbaum, Scott; Romero-Severson, Jeanne

    2008-05-01

    Butternut (Juglans cinerea L.) is an eastern North American forest tree severely threatened by an exotic fungal pathogen, Sirococcus clavigignenti-juglandacearum. We report here 13 nuclear microsatellites for genetic evaluation of the remaining natural populations. Summary statistics are reported for individuals from a population of butternuts in central Kentucky (N = 63). All markers were polymorphic, with an average of 13.7 alleles per locus observed. Four loci exhibited significantly fewer heterozygotes than expected under Hardy-Weinberg equilibrium (P < 0.05). © 2007 The Authors.

  18. Nine microsatellite loci developed from the octocoral, Paragorgia arborea

    Science.gov (United States)

    Coykendall, D. Katharine; Morrison, Cheryl L.

    2015-01-01

    Paragorgia arborea, or bubblegum coral, occurs in continental slope habitats worldwide, which are increasingly threatened by human activities such as energy development and fisheries practices. From 101 putative loci screened, nine microsatellite markers were developed from samples taken from Baltimore canyon in the western North Atlantic Ocean. The number of alleles ranged from two to thirteen per locus and each displayed equilibrium. These nuclear resources will help further research on population connectivity in threatened coral species where mitochondrial markers are known to lack fine-scale genetic diversity.

  19. Electrospun bioactive mats enriched with Ca-polyphosphate/retinol nanospheres as potential wound dressing

    OpenAIRE

    Müller, Werner E.G.; Tolba, Emad; Dorweiler, Bernhard; Schröder, Heinz C.; Diehl-Seifert, Bärbel; Wang, Xiaohong

    2015-01-01

    Background While electrospun materials have been frequently used in tissue engineering no wound dressings exist that significantly improved wound healing effectively. Methods We succeeded to fabricate three-dimensional (3D) electrospun poly(D,l-lactide) (PLA) fiber mats into which nanospheres, formed from amorphous calcium polyphosphate (polyP) nanoparticles (NP) and encapsulated retinol (“retinol/aCa-polyP-NS” nanospheres [NS]), had been incorporated. Results Experiments with MC3T3-E1 cells ...

  20. Matérn's hard core models of types I and II with arbitrary compact grains

    DEFF Research Database (Denmark)

    Kiderlen, Markus; Hörig, Mario

    Matérn's classical hard core models can be interpreted as models obtained from a stationary marked Poisson process by dependent thinning. The marks are balls of fixed radius, and a point is retained when its associated ball does not hit any other balls (type I) or when its random birth time is st...... of this model with the process of intact grains of the dead leaves model and the Stienen model leads to analogous results for the latter....

  1. Comparison of the active and resident community of a coastal microbial mat

    OpenAIRE

    Cardoso, Daniela Clara; Sandionigi, Anna; Cretoiu, Mariana Silvia; Casiraghi, Maurizio; Stal, Lucas; Bolhuis, Henk

    2017-01-01

    Coastal microbial mats form a nearly closed micro-scale ecosystem harboring a complex microbial community. Previous DNA based analysis did not necessarily provide information about the active fraction of the microbial community because it includes dormant, inactive cells as well as a potential stable pool of extracellular DNA. Here we focused on the active microbial community by comparing 16S rRNA sequences obtained from the ribosomal RNA pool with gene sequences obtained from the DNA fractio...

  2. The cyanobacterium Mastigocladus fulfills the nitrogen demand of a terrestrial hot spring microbial mat.

    Science.gov (United States)

    Estrella Alcamán, María; Fernandez, Camila; Delgado, Antonio; Bergman, Birgitta; Díez, Beatriz

    2015-10-01

    Cyanobacteria from Subsection V (Stigonematales) are important components of microbial mats in non-acidic terrestrial hot springs. Despite their diazotrophic nature (N2 fixers), their impact on the nitrogen cycle in such extreme ecosystems remains unknown. Here, we surveyed the identity and activity of diazotrophic cyanobacteria in the neutral hot spring of Porcelana (Northern Patagonia, Chile) during 2009 and 2011-2013. We used 16S rRNA and the nifH gene to analyze the distribution and diversity of diazotrophic cyanobacteria. Our results demonstrate the dominance of the heterocystous genus Mastigocladus (Stigonematales) along the entire temperature gradient of the hot spring (69-38 °C). In situ nitrogenase activity (acetylene reduction), nitrogen fixation rates (cellular uptake of (15)N2) and nifH transcription levels in the microbial mats showed that nitrogen fixation and nifH mRNA expression were light-dependent. Nitrogen fixation activities were detected at temperatures ranging from 58 °C to 46 °C, with maximum daily rates of 600 nmol C2H4 cm(-2) per day and 94.1 nmol N cm(-2) per day. These activity patterns strongly suggest a heterocystous cyanobacterial origin and reveal a correlation between nitrogenase activity and nifH gene expression during diurnal cycles in thermal microbial mats. N and C fixation in the mats contributed ~3 g N m(-2) per year and 27 g C m(-2) per year, suggesting that these vital demands are fully met by the diazotrophic and photoautotrophic capacities of the cyanobacteria in the Porcelana hot spring.

  3. Microbial mats in Antarctica as models for the search of life on the Jovian moon Europa

    International Nuclear Information System (INIS)

    Dudeja, S.; Bhattacherjee, A.B.; Chela-Flores, J.

    2008-06-01

    The possibility of sulfur patches on the Jovian satellite Europa being of biogenic origin is discussed. The presence of microbial mats and the accumulation of sulfur on the surface of some Antarctic subglacial lakes are correlated with the sulfur traces found on Europa by means of microbiological processes. Special attention has been paid to the influence of temperature and radiation on the icy surface of this Jovian satellite. An optimum penetration depth to look for biomarkers is proposed based on biogeochemical parameters. (author)

  4. SemMat: Federated Semantic Services Platform for Open materials Science and Engineering

    Science.gov (United States)

    2017-01-01

    SEMMAT: FEDERATED SEMANTIC SERVICES PLATFORM FOR OPEN MATERIALS SCIENCE AND ENGINEERING WRIGHT STATE UNIVERSITY JANUARY 2017 FINAL TECHNICAL...COVERED (From - To) JUL 2013 – JUN 2016 4. TITLE AND SUBTITLE SemMat: FEDERATED SEMANTIC SERVICES PLATFORM FOR OPEN MATERIALS SCIENCE AND ENGINEERING...models to represent materials data. This provides a data exchange scheme for materials science , which also includes provenance information to promote

  5. Yerba Mat? (Ilex paraguariensis) Metabolic, Satiety, and Mood State Effects at Rest and during Prolonged Exercise

    OpenAIRE

    Alkhatib, Ahmad; Atcheson, Roisin

    2017-01-01

    Yerba Mat? (YM), has become a popular herb ingested for enhancing metabolic health and weight-loss outcomes. No studies have tested the combined metabolic, satiety, and psychomotor effects of YM during exercise. We tested whether YM ingestion affects fatty acid oxidation (FAO), profile of mood state score (POMS), and subjective appetite scale (VAS), during prolonged moderate exercise. Twelve healthy active females were randomized to ingest either 2 g of YM or placebo (PLC) in a repeated-measu...

  6. Influence of layer-by-layer assembled electrospun poly (L-lactic acid) nanofiber mats on the bioactivity of endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Keke; Zhang, Xiazhi; Yang, Wufeng; Liu, Xiaoyan; Jiao, Yanpeng, E-mail: tjiaoyp@jnu.edu.cn; Zhou, Changren

    2016-12-30

    Highlights: • Layer-by-layer assembled PLLA nanofiber mats were successfully prepared. • The modified PLLA nanofiber mats enhanced the adhesion, proliferation of endothelial cells. • The modified PLLA nanofiber mats had inhibited the inflammatory response to some extent. - Abstract: Electrospun poly(L-lactic acid) (PLLA) nanofiber mats were successfully modified by deposition of multilayers with chitosan (CS), heparin (Hep) and graphene oxide (GO) through electrostatic layer-by-layer (LBL) self-assembly method. In this study, the surface properties of PLLA nanofiber mats before and after modification were investigated via scanning electron microscope (SEM), atomic force microscopy (AFM), attenuated total reflectance fourier transformation infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and water contact angle measurement. In addition, the cytocompatibility of the modified PLLA nanofiber mats were investigated by testing endothelial cells compatibility, including cell attachment, cell proliferation and cell cycle. The results revealed that the surfaces of modified PLLA nanofiber mats become much rougher, stifiness and the hydrophilicity of the LBL modified PLLA nanofiber mats were improved compared to original PLLA one. Moreover, the modified PLLA nanofiber mats had promoted the endothelial cells viability attachment significantly. Besides, we studied the PLLA nanofiber mats on the expression of necrosis factor (TNF-α), interleukine-1β (IL-1β), monocyte chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1) in endothelial cells. The results showed that modified PLLA nanofiber mats had inhibited the inflammatory response to some extent.

  7. Rubber matting on an obstacle course causes anterior cruciate ligament ruptures and its removal eliminates them.

    Science.gov (United States)

    Pope, Rodney P

    2002-04-01

    In June 1998, six unexpected anterior cruciate ligament (ACL) ruptures within 12 months were detected by routine injury surveillance in a cohort of Australian Army recruits. Local investigation, reported separately as a Case Report in this issue, suggested the cause to be an excessive coefficient of friction between rubber boot soles and newly laid rubber matting on one obstacle course, creating excessive knee torques. The matting was removed progressively, but not before two more ruptures occurred on one remaining section. In this retrospective study, chi 2 analyses were used to compare the incidence of ACL rupture in prehazard, hazard-exposed, and postintervention cohorts, and the average costs to the institution of each ACL rupture were determined. Zero, eight, and zero ACL ruptures occurred in the prehazard, hazard-exposed, and postintervention cohorts, respectively (chi 2 > 4.75 for 1 df, p < 0.03 for each change in incidence). The temporal relationships between hazard introduction or removal and changes in the incidence of ACL rupture were strong. The average institutional cost of each ACL rupture was AU$54,627 or US$34,322. Rubber matting on obstacle courses increases the risk of ACL rupture in the presence of speed and rubber-soled footwear. Routine injury surveillance and simple preventive processes save money and personnel.

  8. Location and associated carbon storage of erosional escarpments of seagrass Posidonia mats

    Directory of Open Access Journals (Sweden)

    Oscar eSerrano

    2016-03-01

    Full Text Available Seagrasses of the genus Posidonia can form an irregular seascape due to erosional processes exposing thick walls of organic matter-rich soils. However, little is known about the location and characteristics of these particular formations. Here we provide comprehensive estimates of organic carbon (Corg storage in P. oceanica and P. australis meadows, while providing insight into their location and mechanisms of formation, and highlighting future research directions. Erosional reef escarpments are restricted to shallow highly productive P. oceanica meadows from the Mediterranean Sea and P. australis meadows from the Indian Ocean, and sustain the existence of Corg-rich deposits in surrounding meadows. The thickness of the mat escarpments can reach up to 3 m and their length can vary from few to hundreds meters. Mechanisms of formation appear to differ among sites, from naturally-induced escarpments by wave action and/or tidal flow to human-induced escarpments by dredging activities. The inter-twined remains of seagrass shoots within the sediment matrix consolidate the sandy substrate and hold the exposed Posidonia mat escarpments together, maintaining a semi-rigid structure. This phenomenon is unusual but of exceptional importance in marine biogeochemical cycles, revealing the largest Corg sinks among seagrasses worldwide (ranging from 15-176 kg Corg m-2 in 2 m-thick mats accumulated at 2-249 g Corg m-2 yr-1 over 300 to 3000 yr.

  9. Distribution of phototrophic populations and primary production in a microbial mat from the Ebro Delta, Spain.

    Science.gov (United States)

    Martínez-Alonso, Maira; Mir, Joan; Caumette, Pierre; Gaju, Núria; Guerrero, Ricardo; Esteve, Isabel

    2004-03-01

    Microbial mats arising in the sand flats of the Ebro Delta (Tarragona, Spain) were investigated during the summer season, when the community was highly developed. These mats are composed of three pigmented layers of phototrophic organisms, an upper brown layer mainly composed of Lyngbya aestuarii and diatoms, an intermediate green layer of the cyanobacterium Microcoleus chthonoplastes, and an underlying pink layer of a so-far unidentified purple sulfur bacterium. In the photic zone, oxygenic phototrophs constitute about 58% of total photosynthetic biomass, measured as biovolume, and anoxygenic phototrophs represent 42%. Diatoms constitute 11.8% of the oxygenic biomass, M. chthonoplastes 61.2%, and L. aestuarii and coccoid cyanobacteria 20.6 and 6.4%, respectively. In this laminated community, organic matter has an autochthonous origin, and photosynthesis is the most important source of organic carbon. Oxygen production reaches up to 27.2 mmol O(2) m(-2) h(-1), measured at 1000 microE m(-2) s(-1) light intensity, whereas oxidation of sulfide in the light has been calculated to be 18.6 mmol S m(-2) h(-1). This amount represents 26% of the total photosynthetic production in terms of photoassimilated carbon, demonstrating the important role of anoxygenic phototrophs as primary producers in the pink layer of Ebro Delta microbial mats.

  10. Sulfate Reduction and Thiosulfate Transformations in a Cyanobacterial Mat during a Diel Oxygen Cycle

    DEFF Research Database (Denmark)

    JØRGENSEN, BB

    1994-01-01

    Bacterial sulfate reduction and transformations of thiosulfate were studied with radiotracers in a Microcoleus chthono-plastes-dominated microbial mat growing in a hypersaline pond at the Red Sea. The study showed how a diel cycle of oxygen evolution affected respiration by sulfate-reducing bacte......Bacterial sulfate reduction and transformations of thiosulfate were studied with radiotracers in a Microcoleus chthono-plastes-dominated microbial mat growing in a hypersaline pond at the Red Sea. The study showed how a diel cycle of oxygen evolution affected respiration by sulfate......-reducing bacteria and the metabolism of thiosulfate through oxidative and reductive pathways. Sulfate reduction occurred in both oxic and anoxic layers of the mat and varied diurnally, apparently according to temperature rather than to oxygen. Time course experiments showed that the radiotracer method...... underestimated sulfate reduction in the oxic zone due to rapid reoxidation of the produced sulfide. Extremely high reduction rates of up to 10 mu mol cm(-3) d(-1) were measured just below the euphotic zone. Although thiosulfate was simultaneously oxidized, reduced and disproportionated by bacteria in all layers...

  11. A class of Matérn-like covariance functions for smooth processes on a sphere

    KAUST Repository

    Jeong, Jaehong

    2015-02-01

    © 2014 Elsevier Ltd. There have been noticeable advancements in developing parametric covariance models for spatial and spatio-temporal data with various applications to environmental problems. However, literature on covariance models for processes defined on the surface of a sphere with great circle distance as a distance metric is still sparse, due to its mathematical difficulties. It is known that the popular Matérn covariance function, with smoothness parameter greater than 0.5, is not valid for processes on the surface of a sphere with great circle distance. We introduce an approach to produce Matérn-like covariance functions for smooth processes on the surface of a sphere that are valid with great circle distance. The resulting model is isotropic and positive definite on the surface of a sphere with great circle distance, with a natural extension for nonstationarity case. We present extensive numerical comparisons of our model, with a Matérn covariance model using great circle distance as well as chordal distance. We apply our new covariance model class to sea level pressure data, known to be smooth compared to other climate variables, from the CMIP5 climate model outputs.

  12. Estimation of axial stiffness of plant fibres from compaction of non-woven mats

    International Nuclear Information System (INIS)

    Gamstedt, E K; Bommier, E; Madsen, B

    2014-01-01

    Plant fibres are known to show a large variability in stiffness, which makes it time-consuming to experimentally characterize this property by conventional tensile testing. In this work, an alternative method is used, where the average fibre stiffness is back-calculated from compaction tests of in-plane randomly oriented fibre mats. The model by Toll is used to relate the load–displacement curve from the test to the Young modulus of the fibre, taking into account the natural variability in fibre cross section. Several tests have been performed on hemp fibre mats and compared with results from single-fibre tensile testing. The average back-calculated Young's modulus of the fibres was 45 GPa, whereas the average value from tensile testing ranged from 30 to 60 GPa. The straightforward compaction test can be useful in ranking of fibre stiffness, provided that the mat is composed of well-separated fibres and not of twisted yarns. (paper)

  13. A class of Matérn-like covariance functions for smooth processes on a sphere

    KAUST Repository

    Jeong, Jaehong; Jun, Mikyoung

    2015-01-01

    © 2014 Elsevier Ltd. There have been noticeable advancements in developing parametric covariance models for spatial and spatio-temporal data with various applications to environmental problems. However, literature on covariance models for processes defined on the surface of a sphere with great circle distance as a distance metric is still sparse, due to its mathematical difficulties. It is known that the popular Matérn covariance function, with smoothness parameter greater than 0.5, is not valid for processes on the surface of a sphere with great circle distance. We introduce an approach to produce Matérn-like covariance functions for smooth processes on the surface of a sphere that are valid with great circle distance. The resulting model is isotropic and positive definite on the surface of a sphere with great circle distance, with a natural extension for nonstationarity case. We present extensive numerical comparisons of our model, with a Matérn covariance model using great circle distance as well as chordal distance. We apply our new covariance model class to sea level pressure data, known to be smooth compared to other climate variables, from the CMIP5 climate model outputs.

  14. Superhydrophobic PVDF and PVDF-HFP nanofibrous mats with antibacterial and anti-biofouling properties

    Energy Technology Data Exchange (ETDEWEB)

    Spasova, M.; Manolova, N. [Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, Acad. G. Bonchev St, bl. 103A, BG-1113 Sofia (Bulgaria); Markova, N. [Institute of Microbiology, Bulgarian Academy of Sciences, Acad. G. Bonchev St, bl. 26, BG-1113 Sofia (Bulgaria); Rashkov, I., E-mail: rashkov@polymer.bas.bg [Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, Acad. G. Bonchev St, bl. 103A, BG-1113 Sofia (Bulgaria)

    2016-02-15

    Graphical abstract: - Highlights: • New PVDF and PVDF-HFP nanofibers decorated with ZnO nanoparticles and a model drug. • The nanofibrous materials were fabricated by one-pot electrospinning. • The obtained materials are superhybrophobic and possess antibacterial properties. - Abstract: Superhydrophobic nanofibrous materials of poly(vinylidene fluoride) (PVDF) and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) were prepared by one-pot electrospinning technique. The mats were decorated with ZnO nanoparticles with silanized surface and a model drug – 5-chloro-8-hydroxyquinolinol (5Cl8HQ). The obtained hybrid nanofibrous materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), contact angle measurements, mechanical and microbiological tests. The results showed that the incorporation of ZnO nanoparticles into PVDF and PVDF-HFP nanofibers increased the hydrophobicity (contact angle 152°), improved the thermal stability and imparted to the nanofibrous materials anti-adhesive and antimicrobial properties. The mats containing the model drug possessed antibacterial activity against Escherichia coli and Staphylococcus aureus. The results suggested that the obtained hybrid mats could find potential biomedical applications requiring antibacterial and anti-biofouling properties.

  15. The Harris and Beath footprinting mat: diagnostic validity and clinical use.

    Science.gov (United States)

    Silvino, N; Evanski, P M; Waugh, T R

    1980-09-01

    Pain on the plantar aspect of the forefoot is a common malady whose specific cause is often difficult to diagnose. Using the Berkemann Laboratory version of the original mat of Harris and Beath, and a calibration curve, the patterns on a footprint can be translated into their actual pressure values withhin the range of 0.27 kg/cm2 to 4.80 kg/cm2. Using the procedure presented here, inexperienced subjects were able to estimate the pressure values of random prints of unknown pressure within a standard deviation of 0.28 kg/cm2 from their actual values. The mat is valuable for diagnosis of pressure metatarsalgia and other disorders of the foot. The specificity was 0.77, sensitivity was 0.57, with the sum being equal to 1.34. These results indicate that there is a relatively large population of normal people wit excessive localized pressure under their metatarsal heads who do not complain of pain. The apparently low sensitivty of the mat in this study does not seem to be a limitation, but is an indication of the haziness involved in the differential diagnosis of forefoot pain. Pressure metatarsalgia can be quantitated by analysis of the Harris footprint.

  16. Biocidal Activity of Plasma Modified Electrospun Polysulfone Mats Functionalized with Polyethyleneimine-Capped Silver Nanoparticles

    KAUST Repository

    Schiffman, Jessica D.

    2011-11-01

    The incorporation of silver nanoparticles (AgNPs) into polymeric nanofibers has attracted a great deal of attention due to the strong antimicrobial activity that the resulting fibers exhibit. However, bactericidal efficacy of AgNP-coated electrospun fibrous mats has not yet been demonstrated. In this study, polysulfone (PSf) fibers were electrospun and surface-modified using an oxygen plasma treatment, which allowed for facile irreversible deposition of cationically charged polyethyleneimine (PEI)-AgNPs via electrostatic interactions. The PSf-AgNP mats were characterized for relative silver concentration as a function of plasma treatment time using ICP-MS and changes in contact angle. Plasma treatment of 60 s was the shortest time required for maximum loss of bacteria (Escherichia coli) viability. Time-dependent bacterial cytotoxicity studies indicate that the optimized PSf-AgNP mats exhibit a high level of inactivation against both Gram negative bacteria, Escherichia coli, and Gram positive bacteria, Bacillus anthracis and Staphylococcus aureus. © 2011 American Chemical Society.

  17. Resilience and receptivity worked in tandem to sustain a geothermal mat community amidst erratic environmental conditions.

    Science.gov (United States)

    Ghosh, Wriddhiman; Roy, Chayan; Roy, Rimi; Nilawe, Pravin; Mukherjee, Ambarish; Haldar, Prabir Kumar; Chauhan, Neeraj Kumar; Bhattacharya, Sabyasachi; Agarwal, Atima; George, Ashish; Pyne, Prosenjit; Mandal, Subhrangshu; Rameez, Moidu Jameela; Bala, Goutam

    2015-07-17

    To elucidate how geothermal irregularities affect the sustainability of high-temperature microbiomes we studied the synecological dynamics of a geothermal microbial mat community (GMMC) vis-à-vis fluctuations in its environment. Spatiotemporally-discrete editions of a photosynthetic GMMC colonizing the travertine mound of a circum-neutral hot spring cluster served as the model-system. In 2010 a strong geyser atop the mound discharged mineral-rich hot water, which nourished a GMMC continuum from the proximal channels (PC) upto the slope environment (SE) along the mound's western face. In 2011 that geyser extinguished and consequently the erstwhile mats disappeared. Nevertheless, two relatively-weaker vents erupted in the southern slope and their mineral-poor outflow supported a small GMMC patch in the SE. Comparative metagenomics showed that this mat was a relic of the 2010 community, conserved via population dispersal from erstwhile PC as well as SE niches. Subsequently in 2012, as hydrothermal activity augmented in the southern slope, ecological niches widened and the physiologically-heterogeneous components of the 2011 "seed-community" split into PC and SE meta-communities, thereby reclaiming either end of the thermal gradient. Resilience of incumbent populations, and the community's receptiveness towards immigrants, were the key qualities that ensured the GMMC's sustenance amidst habitat degradation and dispersal to discrete environments.

  18. The QMAP and MAT/TOCO Experiments for Measuring Anisotropy in the Cosmic Microwave Background

    Science.gov (United States)

    Miller, A.; Beach, J.; Bradley, S.; Caldwell, R.; Chapman, H.; Devlin, M. J.; Dorwart, W. B.; Herbig, T.; Jones, D.; Monnelly, G.; Netterfield, C. B.; Nolta, M.; Page, L. A.; Puchalla, J.; Robertson, T.; Torbet, E.; Tran, H. T.; Vinje, W. E.

    2002-06-01

    We describe two related experiments that measured the anisotropy in the cosmic microwave background (CMB). QMAP was a balloon-borne telescope that flew twice in 1996, collecting data on degree angular scales with an array of six high electron mobility transistor-based amplifiers (HEMTs). QMAP used an interlocking scan strategy to directly produce high signal-to-noise ratio CMB maps over a limited region of sky. The QMAP gondola was then refitted for ground-based work as the MAT/TOCO experiment. Observations were made from 5200 m on Cerro Toco in Northern Chile in 1997 and 1998 using time domain beam synthesis. MAT/TOCO measured the rise and fall of the CMB angular spectrum, thereby localizing the position of the first peak to lpeak=216+/-14. In addition to describing the instruments, we discuss the data selection methods, check for systematic errors, and compare the MAT/TOCO results to those from recent experiments. The previously reported data are updated to account for a small calibration shift and corrected to account for a small contribution from known sources of foreground emission. The resulting amplitude of the first peak for 160

  19. Electrospinning of doxorubicin loaded silica/poly(ɛ-caprolactone) hybrid fiber mats for sustained drug release

    Science.gov (United States)

    El Gohary, Mohammed I.; El Hady, Bothaina M. Abd; Saeed, Aziza A. Al; Tolba, Emad; El Rashedi, Ahlam M. I.; Saleh, Safaa

    2018-06-01

    Loading of anticancer drugs into electrospun fiber matrices is a portentous approach for clinical treatment of diseased tissues or organs. In this study, doxorubicin hydrochloride (DOX) is added to silica nanoparticles () during the formation of via the sol-gel approach. The obtained nanoparticles are then added to poly(-caprolactone) (PCL) and poly(ethylene oxide) (PEO) blend before electrospinning process via different methods. The effects of DOX addition as a free form or as nanoparticles on physical and chemical properties of obtained PCL-PEO fibers, as well as release profiles are evaluated to give a continual DOX release for several days. The morphology observed with scanning electron microscope (FESEM) revealed significant changes in the average diameter of obtained fibers ranging from 2164 nm to 659 nm and distribution of drug-loaded nanoparticles in the final mats according to the mode of additions. With the same manner, the releasing performances of obtained mats are quite different. Therefore, fabrication of drug loaded mats would offer a powerful approach to minimize serious side effects for clinical patients and allows us to control the drug concentration in the bloodstream.

  20. Free-living spirochetes from Cape Cod microbial mats detected by electron microscopy

    Science.gov (United States)

    Teal, T. H.; Chapman, M.; Guillemette, T.; Margulis, L.

    1996-01-01

    Spirochetes from microbial mats and anaerobic mud samples collected in salt marshes were studied by light microscopy, whole mount and thin section transmission electron microscopy. Enriched in cellobiose-rifampin medium, selective for Spirochaeta bajacaliforniensis, seven distinguishable spirochete morphotypes were observed. Their diameters ranged from 0.17 micron to > 0.45 micron. Six of these morphotypes came from southwest Cape Cod, Massachusetts: five from Microcoleus-dominated mat samples collected at Sippewissett salt marsh and one from anoxic mud collected at School Street salt marsh (on the east side of Eel Pond). The seventh morphotype was enriched from anoxic mud sampled from the north central Cape Cod, at the Sandy Neck salt marsh. Five of these morphotypes are similar or identical to previously described spirochetes (Leptospira, Spirochaeta halophila, Spirochaeta bajacaliforniensis, Spirosymplokos deltaeiberi and Treponema), whereas the other two have unique features that suggest they have not been previously described. One of the morphotypes resembles Spirosymplokos deltaeiberi (the largest free-living spirochete described), in its large variable diameter (0.4-3.0 microns), cytoplasmic granules, and spherical (round) bodies with composite structure. This resemblance permits its tentative identification as a Sippewissett strain of Spirosymplokos deltaeiberi. Microbial mats samples collected in sterile Petri dishes and stored dry for more than four years yielded many organisms upon rewetting, including small unidentified spirochetes in at least 4 out of 100 enrichments.

  1. Polyelectrolyte multilayer film-assisted formation of zero-valent iron nanoparticles onto polymer nanofibrous mats

    International Nuclear Information System (INIS)

    Xiao Shili; Shi Xiangyang; Wu Siqi; Shen Mingwu; Guo Rui; Wang Shanyuan

    2009-01-01

    A facile approach that combines the electrospinning technique and layer-by-layer (LbL) assembly method has been developed to synthesize and immobilize zero-valent iron nanoparticles (ZVI NPs) onto the surface of nanofibers for potential environmental applications. In this approach, negatively charged cellulose acetate (CA) nanofibers fabricated by electrospinning CA solution were modified with bilayers composed of positively charged poly(diallyl-dimethyl-ammoniumchloride) (PDADMAC) and negatively charged poly(acrylic acid) (PAA) through electrostatic LbL assembly approach to form composite nanofibrous mats. The composite nanofibrous mats were immersed into the ferrous iron solution to allow Fe(II) ions to complex with the free carboxyl groups of PAA, and then ZVI NPs were immobilized onto the composite nanofibrous mats instantly by reducing the ferrous cations. Combined scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and thermogravimetry analysis demonstrated that the ZVI NPs are successfully synthesized and uniformly distributed into the polyelectrolyte (PE) multilayer films assembled onto the CA nanofibers. The present approach to synthesis ZVI NPs opens a new avenue to fabricating various materials with high surface area for environmental, catalytic, and sensing applications.

  2. Preparation of Non-Woven Fiber Mats by Mixture of PVC and Epoxidized Natural Rubber

    International Nuclear Information System (INIS)

    Muhammad Hariz Othman; Mahathir Mohamed; Dahlan Mohd

    2014-01-01

    Eletrospun non-woven fibre mats prepared from ENR modified PVC were successfully fabricated at ambient temperature by electro spinning method. Liquid epoxidized natural rubber (LENR) was used because it is easier to handle compared to dried ENR. PVC was mixed with LENR based on 3 different ratios (9:1, 8:2 and 7:3). The effect of ENR on electrospinnibality of PVC was investigated.The morphologies and thermal properties of the electro span fibre mats were characterized and assessed using scanning calorimetry (DSC). The polymer solution concentration 16 aut % formed a diameter of the fibres were mainly affected by the addition of natural rubber and weight ratio of the solution. The diameter of the fibres also decreased with increasing amount of LENR in the solution. Thermal degradation involved two-step degradation with the first degradation representing the dehydro chlorination of PVC to form polyene and followed by the decomposition of LENR and the polyene.Addition of LENR into the sample caused the T g of electro spun fibre mats of PVC/LENR to shift toward lower temperature. (author)

  3. Development of microsatellite loci in Artocarpus altilis (Moraceae) and cross-amplification in congeneric species.

    Science.gov (United States)

    Witherup, Colby; Ragone, Diane; Wiesner-Hanks, Tyr; Irish, Brian; Scheffler, Brian; Simpson, Sheron; Zee, Francis; Zuberi, M Iqbal; Zerega, Nyree J C

    2013-07-01

    Microsatellite loci were isolated and characterized from enriched genomic libraries of Artocarpus altilis (breadfruit) and tested in four Artocarpus species and one hybrid. The microsatellite markers provide new tools for further studies in Artocarpus. • A total of 25 microsatellite loci were evaluated across four Artocarpus species and one hybrid. Twenty-one microsatellite loci were evaluated on A. altilis (241), A. camansi (34), A. mariannensis (15), and A. altilis × mariannensis (64) samples. Nine of those loci plus four additional loci were evaluated on A. heterophyllus (jackfruit, 426) samples. All loci are polymorphic for at least one species. The average number of alleles ranges from two to nine within taxa. • These microsatellite primers will facilitate further studies on the genetic structure and evolutionary and domestication history of Artocarpus species. They will aid in cultivar identification and establishing germplasm conservation strategies for breadfruit and jackfruit.

  4. Development of microsatellite loci in Artocarpus altilis (Moraceae) and cross-amplification in congeneric species1

    Science.gov (United States)

    Witherup, Colby; Ragone, Diane; Wiesner-Hanks, Tyr; Irish, Brian; Scheffler, Brian; Simpson, Sheron; Zee, Francis; Zuberi, M. Iqbal; Zerega, Nyree J. C.

    2013-01-01

    • Premise of the study: Microsatellite loci were isolated and characterized from enriched genomic libraries of Artocarpus altilis (breadfruit) and tested in four Artocarpus species and one hybrid. The microsatellite markers provide new tools for further studies in Artocarpus. • Methods and Results: A total of 25 microsatellite loci were evaluated across four Artocarpus species and one hybrid. Twenty-one microsatellite loci were evaluated on A. altilis (241), A. camansi (34), A. mariannensis (15), and A. altilis × mariannensis (64) samples. Nine of those loci plus four additional loci were evaluated on A. heterophyllus (jackfruit, 426) samples. All loci are polymorphic for at least one species. The average number of alleles ranges from two to nine within taxa. • Conclusions: These microsatellite primers will facilitate further studies on the genetic structure and evolutionary and domestication history of Artocarpus species. They will aid in cultivar identification and establishing germplasm conservation strategies for breadfruit and jackfruit. PMID:25202565

  5. Development of Microsatellite Loci in Artocarpus altilis (Moraceae and Cross-Amplification in Congeneric Species

    Directory of Open Access Journals (Sweden)

    Colby Witherup

    2013-07-01

    Full Text Available Premise of the study: Microsatellite loci were isolated and characterized from enriched genomic libraries of Artocarpus altilis (breadfruit and tested in four Artocarpus species and one hybrid. The microsatellite markers provide new tools for further studies in Artocarpus. Methods and Results: A total of 25 microsatellite loci were evaluated across four Artocarpus species and one hybrid. Twenty-one microsatellite loci were evaluated on A. altilis (241, A. camansi (34, A. mariannensis (15, and A. altilis × mariannensis (64 samples. Nine of those loci plus four additional loci were evaluated on A. heterophyllus (jackfruit, 426 samples. All loci are polymorphic for at least one species. The average number of alleles ranges from two to nine within taxa. Conclusions: These microsatellite primers will facilitate further studies on the genetic structure and evolutionary and domestication history of Artocarpus species. They will aid in cultivar identification and establishing germplasm conservation strategies for breadfruit and jackfruit.

  6. Avasõnad / Mats Estonius, Toomas Hendrik Ilves, Eduardo Ibáñes, Uffe A. Baslev

    Index Scriptorium Estoniae

    2010-01-01

    Konverentsi avasõnad laususid Tallinna Ülikooli prorektor Mats Estonius, Eesti Vabariigi president Toomas Hendrik Ilves, Hispaania Kuningriigi suursaadik Eestis Eduardo Ibáñes, Taani Kuningriigi suursaadik Eestis Uffe A. Baslev

  7. Mechanical and electro-rheological properties of electrospun poly(vinyl alcohol) nanofibre mats filled with carbon black nanoparticles

    International Nuclear Information System (INIS)

    Chuangchote, Surawut; Sirivat, Anuvat; Supaphol, Pitt

    2007-01-01

    The present contribution reports, for the first time, the mechanical and electro-rheological properties of electrospun poly(vinyl alcohol) (PVA) nanofibre mats with or without the incorporation of carbon black (CB) nanoparticles. The effects of sonication and the addition of CB on morphological appearance, average diameter of the as-spun fibre mats, and that of the individual fibres, were thoroughly investigated. Incorporation of CB (1-10% based on the weight of PVA) in 10% w/v PVA solution did not affect the morphology and average diameter of the obtained fibres (∼160 nm), but it affected both the mechanical and the electro-rheological properties of the as-spun PVA/CB fibre mats, in which the mats became more rigid with the addition and increasing amount of CB

  8. Expansion rate and geometry of floating vegetation mats on the margins of thermokarst lakes, northern Seward Peninsula, Alaska, USA

    Science.gov (United States)

    Parsekian, A.D.; Jones, Benjamin M.; Jones, M.; Grosse, G.; Walter, Anthony K.M.; Slater, L.

    2011-01-01

    Investigations on the northern Seward Peninsula in Alaska identified zones of recent (geometry is determined using geophysical and remote sensing measurements. The vegetation mats were observed to have an average thickness of 0.57m and petrophysical modeling indicated that gas content of 1.5-5% enabled floatation above the lake surface. Furthermore, geophysical investigation provides evidence that the mats form by thaw and subsidence of the underlying permafrost rather than terrestrialization. The temperature of the water below a vegetation mat was observed to remain above freezing late in the winter. Analysis of satellite and aerial imagery indicates that these features have expanded at maximum rates of 1-2myr-1 over a 56year period. Including the spatial coverage of floating 'thermokarst mats' increases estimates of lake area by as much as 4% in some lakes. ?? 2011 John Wiley & Sons, Ltd.

  9. Clinical evaluation of the Byk LIA-mat CA125 II assay: discussion of a reference value.

    Science.gov (United States)

    Bonfrer, J M; Korse, C M; Verstraeten, R A; van Kamp, G J; Hart, G A; Kenemans, P

    1997-03-01

    The Byk LIA-mat CA125 II assay was compared with the Centocor IRMA CA125 II. Serum samples studied (n = 1012) were obtained from 652 apparently healthy females, 61 pregnant women, and 299 patients with benign and malignant gynecological tumors. The CA125 II assay value at the 95th percentile of the total healthy group was 29 kU/L for the LIA-mat and 32 kU/L for the Centocor assay. For the LIA-mat assay the 95th percentile was 31 kU/L (Centocor 36 kU/L) for the group 55 years of age. By using ROC curves we found the optimal pretreatment Byk LIA-mat CA125 II value differentiating between benign and malignant ovarian tumors to be 95 kU/L. Pretreatment CA125 values > 1000 kU/L were detected in serum samples of patients with advanced epithelial ovarian cancer.

  10. Identification of heart rate–associated loci and their effects on cardiac conduction and rhythm disorders

    OpenAIRE

    den Hoed, Marcel; Eijgelsheim, Mark; Esko, Tõnu; Brundel, Bianca J J M; Peal, David S; Evans, David M; Nolte, Ilja M; Segrè, Ayellet V; Holm, Hilma; Handsaker, Robert E; Westra, Harm-Jan; Johnson, Toby; Isaacs, Aaron; Yang, Jian; Lundby, Alicia

    2013-01-01

    Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously established loci. Experimental downregulation of gene expression in Drosophila melanogaster and Danio rerio identified 20 genes at 11 loci that are relevant for heart rate regulation and highlight a rol...

  11. Genetics analysis of 38 STR loci in Uygur population from Southern Xinjiang of China.

    Science.gov (United States)

    Yuan, Li; Liu, Haibo; Liao, Qinxiang; Xu, Xu; Chen, Wen; Hao, Shicheng

    2016-05-01

    The allele frequencies and statistical parameters of 38 autosomal short tandem repeat (STR) loci were analyzed in the Uygur population from Southern Xinjiang of China with 290 unrelated individuals. The results show these 38 STR loci have high or medium power of discrimination and probabilities of exclusion. All loci are in Hardy-Weinberg equilibrium. The genetic distances between the Uygur population and other Chinese populations were also estimated.

  12. Black Mats, Spring-Fed Streams, and Late-Glacial-Age Recharge in the Southern Great Basin

    Science.gov (United States)

    Quade, Jay; Forester, R.M.; Pratt, W.L.; Carter, C.

    1998-01-01

    Black mats are prominent features of the late Pleistocene and Holocene stratigraphic record in the southern Great Basin. Faunal, geochemical, and sedimentological evidence shows that the black mats formed in several microenvironments related to spring discharge, ranging from wet meadows to shallow ponds. Small land snails such as Gastrocopta tappaniana and Vertigo berryi are the most common mollusk taxa present. Semiaquatic and aquatic taxa are less abundant and include Catinellids, Fossaria parva, Gyraulus parvus, and others living today in and around perennial seeps and ponds. The ostracodes Cypridopsis okeechobi and Scottia tumida, typical of seeps and low-discharge springs today, as well as other taxa typical of springs and wetlands, are common in the black mats. Several new species that lived in the saturated subsurface also are present, but lacustrine ostracodes are absent. The ??13C values of organic matter in the black mats range from -12 to -26???, reflecting contributions of tissue from both C3 (sedges, most shrubs and trees) and C4 (saltbush, saltgrass) plants. Carbon-14 dates on the humate fraction of 55 black mats fall between 11,800 to 6300 and 2300 14C yr B.P. to modern. The total absence of mats in our sample between 6300 and 2300 14C yr B.P. likely reflects increased aridity associated with the mid-Holocene Altithermal. The oldest black mats date to 11,800-11,600 14C yr B.P., and the peak in the 14C black mat distribution falls at ???10,000 14C yr B.P. As the formation of black mats is spring related, their abundance reflects refilling of valley aquifers starting no later than 11,800 and peaking after 11,000 14C yrB.P. Reactivation of spring-fed channels shortly before 11,200 14C yr B.P. is also apparent in the stratigraphic records from the Las Vegas and Pahrump Valleys. This age distribution suggests that black mats and related spring-fed channels in part may have formed in response to Younger Dryas (YD)-age recharge in the region. However, the

  13. Diversity and microevolution of CRISPR loci in Helicobacter cinaedi.

    Directory of Open Access Journals (Sweden)

    Junko Tomida

    Full Text Available Helicobacter cinaedi is associated with nosocomial infections. The CRISPR-Cas system provides adaptive immunity against foreign genetic elements. We investigated the CRISPR-Cas system in H. cinaedi to assess the potential of the CRISPR-based microevolution of H. cinaedi strains. A genotyping method based on CRISPR spacer organization was carried out using 42 H. cinaedi strains. The results of sequence analysis showed that the H. cinaedi strains used in this study had two CRISPR loci (CRISPR1 and CRISPR2. The lengths of the consensus direct repeat sequences in CRISPR1 and CRISPR2 were both 36 bp-long, and 224 spacers were found in the 42 H. cinaedi strains. Analysis of the organization and sequence similarity of the spacers of the H. cinaedi strains showed that CRISPR arrays could be divided into 7 different genotypes. Each genotype had a different ancestral spacer, and spacer acquisition/deletion events occurred while isolates were spreading. Spacer polymorphisms of conserved arrays across the strains were instrumental for differentiating closely-related strains collected from the same hospital. MLST had little variability, while the CRISPR sequences showed remarkable diversity. Our data revealed the structural features of H. cinaedi CRISPR loci for the first time. CRISPR sequences constitute a valuable basis for genotyping, provide insights into the divergence and relatedness between closely-related strains, and reflect the microevolutionary process of H. cinaedi.

  14. [SSR loci information analysis in transcriptome of Andrographis paniculata].

    Science.gov (United States)

    Li, Jun-Ren; Chen, Xiu-Zhen; Tang, Xiao-Ting; He, Rui; Zhan, Ruo-Ting

    2018-06-01

    To study the SSR loci information and develop molecular markers, a total of 43 683 Unigenes in transcriptome of Andrographis paniculata were used to explore SSR. The distribution frequency of SSR and the basic characteristics of repeat motifs were analyzed using MicroSAtellite software, SSR primers were designed by Primer 3.0 software and then validated by PCR. Moreover, the gene function analysis of SSR Unigene was obtained by Blast. The results showed that 14 135 SSR loci were found in the transcriptome of A. paniculata, which distributed in 9 973 Unigenes with a distribution frequency of 32.36%. Di-nucleotide and Tri-nucleotide repeat were the main types, accounted for 75.54% of all SSRs. The repeat motifs of AT/AT and CCG/CGG were the predominant repeat types of Di-nucleotide and Tri-nucleotide, respectively. A total of 4 740 pairs of SSR primers with the potential to produce polymorphism were designed for maker development. Ten pairs of primers in 20 pairs of randomly picked primers produced fragments with expected molecular size. The gene function of Unigenes containing SSR were mostly related to the basic metabolism function of A. paniculata. The SSR markers in transcriptome of A. paniculata show rich type, strong specificity and high potential of polymorphism, which will benefit the candidate gene mining and marker-assisted breeding. Copyright© by the Chinese Pharmaceutical Association.

  15. Evolution of Microsatellite Loci of Tropical and Temperate Anguilla Eels

    Directory of Open Access Journals (Sweden)

    Mei-Chen Tseng

    2012-04-01

    Full Text Available Anguilla eels are divided into temperate and tropical eels, based on their major distributions. The present study collected two temperate eels, Anguilla japonica and Anguilla anguilla, and two tropical eels, Anguilla marmorata and Anguilla bicolor pacifica, to examine two questions: do temperate and tropical Anguilla eels have different genetic polymorphic patterns?; and do temperate Anguilla japonica and Anguilla anguilla have a closer relationship to each other than to tropical eels? In total, 274 sequences were cloned and sequenced from six conserved microsatellite loci to examine polymorphic patterns of these four catadromous eels. Different mutational events, including substitutions, and repeat-unit deletions and insertions, appeared in major regions, while different point mutations were observed in flanking regions. The results implied that parallel patterns of microsatellite sequences occurred within both tropical and temperate freshwater eels. Consensus flanking sequences of six homologous loci from each of the four species were constructed. Genetic distances ranged from 0.044 (Anguilla bicolor pacifica vs. Anguilla marmorata to 0.061 (Anguilla marmorata vs. Anguilla anguilla. The tree topology suggests the hypothesis of Anguilla japonica and Anguilla anguilla being a sister group must be rejected.

  16. Genetic susceptibility loci, pesticide exposure and prostate cancer risk.

    Directory of Open Access Journals (Sweden)

    Stella Koutros

    Full Text Available Uncovering SNP (single nucleotide polymorphisms-environment interactions can generate new hypotheses about the function of poorly characterized genetic variants and environmental factors, like pesticides. We evaluated SNP-environment interactions between 30 confirmed prostate cancer susceptibility loci and 45 pesticides and prostate cancer risk in 776 cases and 1,444 controls in the Agricultural Health Study. We used unconditional logistic regression to estimate odds ratios (ORs and 95% confidence intervals (CIs. Multiplicative SNP-pesticide interactions were calculated using a likelihood ratio test. After correction for multiple tests using the False Discovery Rate method, two interactions remained noteworthy. Among men carrying two T alleles at rs2710647 in EH domain binding protein 1 (EHBP1 SNP, the risk of prostate cancer in those with high malathion use was 3.43 times those with no use (95% CI: 1.44-8.15 (P-interaction= 0.003. Among men carrying two A alleles at rs7679673 in TET2, the risk of prostate cancer associated with high aldrin use was 3.67 times those with no use (95% CI: 1.43, 9.41 (P-interaction= 0.006. In contrast, associations were null for other genotypes. Although additional studies are needed and the exact mechanisms are unknown, this study suggests known genetic susceptibility loci may modify the risk between pesticide use and prostate cancer.

  17. The signature of positive selection at randomly chosen loci.

    Science.gov (United States)

    Przeworski, Molly

    2002-03-01

    In Drosophila and humans, there are accumulating examples of loci with a significant excess of high-frequency-derived alleles or high levels of linkage disequilibrium, relative to a neutral model of a random-mating population of constant size. These are features expected after a recent selective sweep. Their prevalence suggests that positive directional selection may be widespread in both species. However, as I show here, these features do not persist long after the sweep ends: The high-frequency alleles drift to fixation and no longer contribute to polymorphism, while linkage disequilibrium is broken down by recombination. As a result, loci chosen without independent evidence of recent selection are not expected to exhibit either of these features, even if they have been affected by numerous sweeps in their genealogical history. How then can we explain the patterns in the data? One possibility is population structure, with unequal sampling from different subpopulations. Alternatively, positive selection may not operate as is commonly modeled. In particular, the rate of fixation of advantageous mutations may have increased in the recent past.

  18. Association analysis identifies 65 new breast cancer risk loci.

    Science.gov (United States)

    Michailidou, Kyriaki; Lindström, Sara; Dennis, Joe; Beesley, Jonathan; Hui, Shirley; Kar, Siddhartha; Lemaçon, Audrey; Soucy, Penny; Glubb, Dylan; Rostamianfar, Asha; Bolla, Manjeet K; Wang, Qin; Tyrer, Jonathan; Dicks, Ed; Lee, Andrew; Wang, Zhaoming; Allen, Jamie; Keeman, Renske; Eilber, Ursula; French, Juliet D; Qing Chen, Xiao; Fachal, Laura; McCue, Karen; McCart Reed, Amy E; Ghoussaini, Maya; Carroll, Jason S; Jiang, Xia; Finucane, Hilary; Adams, Marcia; Adank, Muriel A; Ahsan, Habibul; Aittomäki, Kristiina; Anton-Culver, Hoda; Antonenkova, Natalia N; Arndt, Volker; Aronson, Kristan J; Arun, Banu; Auer, Paul L; Bacot, François; Barrdahl, Myrto; Baynes, Caroline; Beckmann, Matthias W; Behrens, Sabine; Benitez, Javier; Bermisheva, Marina; Bernstein, Leslie; Blomqvist, Carl; Bogdanova, Natalia V; Bojesen, Stig E; Bonanni, Bernardo; Børresen-Dale, Anne-Lise; Brand, Judith S; Brauch, Hiltrud; Brennan, Paul; Brenner, Hermann; Brinton, Louise; Broberg, Per; Brock, Ian W; Broeks, Annegien; Brooks-Wilson, Angela; Brucker, Sara Y; Brüning, Thomas; Burwinkel, Barbara; Butterbach, Katja; Cai, Qiuyin; Cai, Hui; Caldés, Trinidad; Canzian, Federico; Carracedo, Angel; Carter, Brian D; Castelao, Jose E; Chan, Tsun L; David Cheng, Ting-Yuan; Seng Chia, Kee; Choi, Ji-Yeob; Christiansen, Hans; Clarke, Christine L; Collée, Margriet; Conroy, Don M; Cordina-Duverger, Emilie; Cornelissen, Sten; Cox, David G; Cox, Angela; Cross, Simon S; Cunningham, Julie M; Czene, Kamila; Daly, Mary B; Devilee, Peter; Doheny, Kimberly F; Dörk, Thilo; Dos-Santos-Silva, Isabel; Dumont, Martine; Durcan, Lorraine; Dwek, Miriam; Eccles, Diana M; Ekici, Arif B; Eliassen, A Heather; Ellberg, Carolina; Elvira, Mingajeva; Engel, Christoph; Eriksson, Mikael; Fasching, Peter A; Figueroa, Jonine; Flesch-Janys, Dieter; Fletcher, Olivia; Flyger, Henrik; Fritschi, Lin; Gaborieau, Valerie; Gabrielson, Marike; Gago-Dominguez, Manuela; Gao, Yu-Tang; Gapstur, Susan M; García-Sáenz, José A; Gaudet, Mia M; Georgoulias, Vassilios; Giles, Graham G; Glendon, Gord; Goldberg, Mark S; Goldgar, David E; González-Neira, Anna; Grenaker Alnæs, Grethe I; Grip, Mervi; Gronwald, Jacek; Grundy, Anne; Guénel, Pascal; Haeberle, Lothar; Hahnen, Eric; Haiman, Christopher A; Håkansson, Niclas; Hamann, Ute; Hamel, Nathalie; Hankinson, Susan; Harrington, Patricia; Hart, Steven N; Hartikainen, Jaana M; Hartman, Mikael; Hein, Alexander; Heyworth, Jane; Hicks, Belynda; Hillemanns, Peter; Ho, Dona N; Hollestelle, Antoinette; Hooning, Maartje J; Hoover, Robert N; Hopper, John L; Hou, Ming-Feng; Hsiung, Chia-Ni; Huang, Guanmengqian; Humphreys, Keith; Ishiguro, Junko; Ito, Hidemi; Iwasaki, Motoki; Iwata, Hiroji; Jakubowska, Anna; Janni, Wolfgang; John, Esther M; Johnson, Nichola; Jones, Kristine; Jones, Michael; Jukkola-Vuorinen, Arja; Kaaks, Rudolf; Kabisch, Maria; Kaczmarek, Katarzyna; Kang, Daehee; Kasuga, Yoshio; Kerin, Michael J; Khan, Sofia; Khusnutdinova, Elza; Kiiski, Johanna I; Kim, Sung-Won; Knight, Julia A; Kosma, Veli-Matti; Kristensen, Vessela N; Krüger, Ute; Kwong, Ava; Lambrechts, Diether; Le Marchand, Loic; Lee, Eunjung; Lee, Min Hyuk; Lee, Jong Won; Neng Lee, Chuen; Lejbkowicz, Flavio; Li, Jingmei; Lilyquist, Jenna; Lindblom, Annika; Lissowska, Jolanta; Lo, Wing-Yee; Loibl, Sibylle; Long, Jirong; Lophatananon, Artitaya; Lubinski, Jan; Luccarini, Craig; Lux, Michael P; Ma, Edmond S K; MacInnis, Robert J; Maishman, Tom; Makalic, Enes; Malone, Kathleen E; Kostovska, Ivana Maleva; Mannermaa, Arto; Manoukian, Siranoush; Manson, JoAnn E; Margolin, Sara; Mariapun, Shivaani; Martinez, Maria Elena; Matsuo, Keitaro; Mavroudis, Dimitrios; McKay, James; McLean, Catriona; Meijers-Heijboer, Hanne; Meindl, Alfons; Menéndez, Primitiva; Menon, Usha; Meyer, Jeffery; Miao, Hui; Miller, Nicola; Taib, Nur Aishah Mohd; Muir, Kenneth; Mulligan, Anna Marie; Mulot, Claire; Neuhausen, Susan L; Nevanlinna, Heli; Neven, Patrick; Nielsen, Sune F; Noh, Dong-Young; Nordestgaard, Børge G; Norman, Aaron; Olopade, Olufunmilayo I; Olson, Janet E; Olsson, Håkan; Olswold, Curtis; Orr, Nick; Pankratz, V Shane; Park, Sue K; Park-Simon, Tjoung-Won; Lloyd, Rachel; Perez, Jose I A; Peterlongo, Paolo; Peto, Julian; Phillips, Kelly-Anne; Pinchev, Mila; Plaseska-Karanfilska, Dijana; Prentice, Ross; Presneau, Nadege; Prokofyeva, Darya; Pugh, Elizabeth; Pylkäs, Katri; Rack, Brigitte; Radice, Paolo; Rahman, Nazneen; Rennert, Gadi; Rennert, Hedy S; Rhenius, Valerie; Romero, Atocha; Romm, Jane; Ruddy, Kathryn J; Rüdiger, Thomas; Rudolph, Anja; Ruebner, Matthias; Rutgers, Emiel J T; Saloustros, Emmanouil; Sandler, Dale P; Sangrajrang, Suleeporn; Sawyer, Elinor J; Schmidt, Daniel F; Schmutzler, Rita K; Schneeweiss, Andreas; Schoemaker, Minouk J; Schumacher, Fredrick; Schürmann, Peter; Scott, Rodney J; Scott, Christopher; Seal, Sheila; Seynaeve, Caroline; Shah, Mitul; Sharma, Priyanka; Shen, Chen-Yang; Sheng, Grace; Sherman, Mark E; Shrubsole, Martha J; Shu, Xiao-Ou; Smeets, Ann; Sohn, Christof; Southey, Melissa C; Spinelli, John J; Stegmaier, Christa; Stewart-Brown, Sarah; Stone, Jennifer; Stram, Daniel O; Surowy, Harald; Swerdlow, Anthony; Tamimi, Rulla; Taylor, Jack A; Tengström, Maria; Teo, Soo H; Beth Terry, Mary; Tessier, Daniel C; Thanasitthichai, Somchai; Thöne, Kathrin; Tollenaar, Rob A E M; Tomlinson, Ian; Tong, Ling; Torres, Diana; Truong, Thérèse; Tseng, Chiu-Chen; Tsugane, Shoichiro; Ulmer, Hans-Ulrich; Ursin, Giske; Untch, Michael; Vachon, Celine; van Asperen, Christi J; Van Den Berg, David; van den Ouweland, Ans M W; van der Kolk, Lizet; van der Luijt, Rob B; Vincent, Daniel; Vollenweider, Jason; Waisfisz, Quinten; Wang-Gohrke, Shan; Weinberg, Clarice R; Wendt, Camilla; Whittemore, Alice S; Wildiers, Hans; Willett, Walter; Winqvist, Robert; Wolk, Alicja; Wu, Anna H; Xia, Lucy; Yamaji, Taiki; Yang, Xiaohong R; Har Yip, Cheng; Yoo, Keun-Young; Yu, Jyh-Cherng; Zheng, Wei; Zheng, Ying; Zhu, Bin; Ziogas, Argyrios; Ziv, Elad; Lakhani, Sunil R; Antoniou, Antonis C; Droit, Arnaud; Andrulis, Irene L; Amos, Christopher I; Couch, Fergus J; Pharoah, Paul D P; Chang-Claude, Jenny; Hall, Per; Hunter, David J; Milne, Roger L; García-Closas, Montserrat; Schmidt, Marjanka K; Chanock, Stephen J; Dunning, Alison M; Edwards, Stacey L; Bader, Gary D; Chenevix-Trench, Georgia; Simard, Jacques; Kraft, Peter; Easton, Douglas F

    2017-11-02

    Breast cancer risk is influenced by rare coding variants in susceptibility genes, such as BRCA1, and many common, mostly non-coding variants. However, much of the genetic contribution to breast cancer risk remains unknown. Here we report the results of a genome-wide association study of breast cancer in 122,977 cases and 105,974 controls of European ancestry and 14,068 cases and 13,104 controls of East Asian ancestry. We identified 65 new loci that are associated with overall breast cancer risk at P < 5 × 10 -8 . The majority of credible risk single-nucleotide polymorphisms in these loci fall in distal regulatory elements, and by integrating in silico data to predict target genes in breast cells at each locus, we demonstrate a strong overlap between candidate target genes and somatic driver genes in breast tumours. We also find that heritability of breast cancer due to all single-nucleotide polymorphisms in regulatory features was 2-5-fold enriched relative to the genome-wide average, with strong enrichment for particular transcription factor binding sites. These results provide further insight into genetic susceptibility to breast cancer and will improve the use of genetic risk scores for individualized screening and prevention.

  19. Production and Consumption of Hydrogen in Hot Spring Microbial Mats Dominated by a Filamentous Anoxygenic Photosynthetic Bacterium

    Science.gov (United States)

    Otaki, Hiroyo; Everroad, R. Craig; Matsuura, Katsumi; Haruta, Shin

    2012-01-01

    Microbial mats containing the filamentous anoxygenic photosynthetic bacterium Chloroflexus aggregans develop at Nakabusa hot spring in Japan. Under anaerobic conditions in these mats, interspecies interaction between sulfate-reducing bacteria as sulfide producers and C. aggregans as a sulfide consumer has been proposed to constitute a sulfur cycle; however, the electron donor utilized for microbial sulfide production at Nakabusa remains to be identified. In order to determine this electron donor and its source, ex situ experimental incubation of mats was explored. In the presence of molybdate, which inhibits biological sulfate reduction, hydrogen gas was released from mat samples, indicating that this hydrogen is normally consumed as an electron donor by sulfate-reducing bacteria. Hydrogen production decreased under illumination, indicating that C. aggregans also functions as a hydrogen consumer. Small amounts of hydrogen may have also been consumed for sulfur reduction. Clone library analysis of 16S rRNA genes amplified from the mats indicated the existence of several species of hydrogen-producing fermentative bacteria. Among them, the most dominant fermenter, Fervidobacterium sp., was successfully isolated. This isolate produced hydrogen through the fermentation of organic carbon. Dispersion of microbial cells in the mats resulted in hydrogen production without the addition of molybdate, suggesting that simultaneous production and consumption of hydrogen in the mats requires dense packing of cells. We propose a cyclic electron flow within the microbial mats, i.e., electron flow occurs through three elements: S (elemental sulfur, sulfide, sulfate), C (carbon dioxide, organic carbon) and H (di-hydrogen, protons). PMID:22446313

  20. Environmental controls on photosynthetic microbial mat distribution and morphogenesis on a 3.42 Ga clastic-starved platform.

    Science.gov (United States)

    Tice, Michael M

    2009-12-01

    Three morphotypes of microbial mats are preserved in rocks deposited in shallow-water facies of the 3.42 Ga Buck Reef chert (BRC). Morphotype alpha consists of fine anastomosing and bifurcating carbonaceous laminations, which loosely drape underlying detrital grains or form silica-filled lenses. Morphotype beta consists of meshes of fine carbonaceous strands intergrown with detrital grains and dark laminations, which loosely drape coarse detrital grains. Morphotype gamma consists of fine, even carbonaceous laminations that tightly drape underlying detrital grains. Preservation of nearly uncompacted mat morphologies and detrital grains deposited during mat growth within a well-characterized sedimentary unit makes quantitative correlation between morphology and paleoenvironment possible. All mats are preserved in the shallowest-water interval of those rocks deposited below normal wave base and above storm wave base. This interval is bounded below by a transgressive lag formed during regional flooding and above by a small condensed section that marks a local relative sea-level maximum. Restriction of all mat morphotypes to the shallowest interval of the storm-active layer in the BRC ocean reinforces previous interpretations that these mats were constructed primarily by photosynthetic organisms. Morphotypes alpha and beta dominate the lower half of this interval and grew during deposition of relatively coarse detrital carbonaceous grains, while morphotype gamma dominates the upper half and grew during deposition of fine detrital carbonaceous grains. The observed mat distribution suggests that either light intensity or, more likely, small variations in ambient current energy acted as a first-order control on mat morphotype distribution. These results demonstrate significant environmental control on biological morphogenetic processes independent of influences from siliciclastic sedimentation.

  1. Timescales of Growth Response of Microbial Mats to Environmental Change in an Ice-Covered Antarctic Lake

    Directory of Open Access Journals (Sweden)

    Anne D. Jungblut

    2013-01-01

    Full Text Available Lake Vanda is a perennially ice-covered, closed-basin lake in the McMurdo Dry Valleys, Antarctica. Laminated photosynthetic microbial mats cover the floor of the lake from below the ice cover to >40 m depth. In recent decades, the water level of Lake Vanda has been rising, creating a “natural experiment” on development of mat communities on newly flooded substrates and the response of deeper mats to declining irradiance. Mats in recently flooded depths accumulate one lamina (~0.3 mm per year and accrue ~0.18 µg chlorophyll-a cm−2 y−1. As they increase in thickness, vertical zonation becomes evident, with the upper 2-4 laminae forming an orange-brown zone, rich in myxoxanthophyll and dominated by intertwined Leptolyngbya trichomes. Below this, up to six phycobilin-rich green/pink-pigmented laminae form a subsurface zone, inhabited by Leptolyngbya, Oscillatoria and Phormidium morphotypes. Laminae continued to increase in thickness for several years after burial, and PAM fluorometry indicated photosynthetic potential in all pigmented laminae. At depths that have been submerged for >40 years, mats showed similar internal zonation and formed complex pinnacle structures that were only beginning to appear in shallower mats. Chlorophyll-a did not change over time and these mats appear to represent resource-limited “climax” communities. Acclimation of microbial mats to changing environmental conditions is a slow process, and our data show how legacy effects of past change persist into the modern community structure.

  2. Novel Large Sulfur Bacteria in the Metagenomes of Groundwater-Fed Chemosynthetic Microbial Mats in the Lake Huron Basin

    OpenAIRE

    Allison M. Sharrar; Beverly E. Flood; Jake V. Bailey; Daniel S. Jones; Daniel S. Jones; Bopaiah A. Biddanda; Steven A. Ruberg; Daniel N. Marcus; Gregory J. Dick

    2017-01-01

    Little is known about large sulfur bacteria (LSB) that inhabit sulfidic groundwater seeps in large lakes. To examine how geochemically relevant microbial metabolisms are partitioned among community members, we conducted metagenomic analysis of a chemosynthetic microbial mat in the Isolated Sinkhole, which is in a deep, aphotic environment of Lake Huron. For comparison, we also analyzed a white mat in an artesian fountain that is fed by groundwater similar to Isolated Sinkhole, but that sits i...

  3. Chitosan-rectorite nanospheres immobilized on polystyrene fibrous mats via alternate electrospinning/electrospraying techniques for copper ions adsorption

    Science.gov (United States)

    Tu, Hu; Huang, Mengtian; Yi, Yang; Li, Zhenshun; Zhan, Yingfei; Chen, Jiajia; Wu, Yang; Shi, Xiaowen; Deng, Hongbing; Du, Yumin

    2017-12-01

    Chitosan (CS), as a kind of well characterized biopolymer, has been used for heavy metal adsorption due to its low cost and high efficacy. However, when used directly, chitosan particles had small surface area and weak mechanical strength which is unfavorable to metal adsorption and reused. Besides, it cannot be easily recycled that may cause a secondary pollution. In this paper, CS and layered silicate rectorite (REC) were fully mixed and the mixtures were subsequently electrosprayed nano-sized spheres, which were immobilized on the surface of electrospun polystyrene (PS) mats for metal adsorption. The morphology analysis taken from SEM confirmed that CS-REC nanospheres were loaded on the surface of PS fibrous mats. Small Angle X-ray diffraction patterns showed that the interlayer distance of REC in composite mats was enlarged by the intercalation of CS chains; such structure meant bigger surface area which was helpful for metal adsorption. The data of contact angle implied that PS mats coated with CS-REC nanospheres exhibited better hydrophilicity than PS mats, which was conductive to adsorption rate. Besides, the copper ions adsorption of composite mats was tested at different conditions including the adsorption time, the initial pH and the initial concentration of copper ion. The results demonstrated that PS mats coated with CS-REC nanospheres had the adsorption capacity up to 134 mg/g. In addition, the addition of REC containing Ca2+ could also improve the metal adsorption because of cation exchange. The desorption assay indicated that PS mats immobilized with CS and CS-REC still kept high adsorption ability which retained 74% and 78% after three adsorption-desorption cycles.

  4. Metagenomic Assembly of the Dominant Zetaproteobacteria in an Iron-oxidizing Hydrothermal Microbial Mat

    Science.gov (United States)

    Moyer, C. L.; Fullerton, H.

    2013-12-01

    Iron is the fourth most abundant element in the Earth's crust and is potentially one of the most abundant energy sources on the earth as an electron donor for chemolithoautotrophic growth coupled to Fe(II) oxidation. Despite the rapid abiotic oxidation rate of iron, many microbes have adapted to feeding off this fleeting energy source. One such bacterial class is the Zetaproteobacteria. Iron-dominated microbial mat material was collected with a small-scale syringe sampler from Loihi Seamount, Hawaii. From this sample, gDNA was extracted and prepared for paired-end Illumina sequencing. Reconstruction of SSU rDNA genes using EMERGE allowed for comparison to previous SSU rDNA surveys. Clone libraries and qPCR show these microbial mats to be dominated by Zetaproteobacteria. Results from our in silico reconstruction confirm these initial findings. RDP classification of the EMERGE reconstructed sequences resulted in 44% of the community being identified as Zetaproteobacteria. The most abundant SSU rDNA has 99% similarity to Zeta OTU-2, and only a 94% similarity to M. ferrooxidans PV-1. Zeta OTU-2 has been shown to be the most cosmopolitan population in iron-dominated hydrothermal systems from across Pacific Ocean. Metagenomic assembly has resulted in many contigs with high identity to M. ferrooxidans as identified, by BLAST. However, with large differences in SSU rRNA similarity, M. ferrooxidans PV-1 is not an adequate reference. Current work is focusing on reconstruction of the dominant microbial mat member, without the use of a reference genome through an iterative assembly approach. The resulting 'pan-genome' will be compared to other Zetaproteobacteria (at the class level) and the functional ecology of this cosmopolitan microbial mat community member will be extrapolated. Thus far, we have detected multiple housekeeping genes involved in DNA replication, transcription and translation. The most abundant metabolic gene we have found is Aconitase, a key enzyme in the

  5. Characterization of microsatellite loci from two-spotted octopus Octopus bimaculatus Verrill 1883 from pyrosequencing reads

    Science.gov (United States)

    Domínguez-Contreras, J. F.; Munguía-Vega, A.; Ceballos-Vázquez, B. P.; Arellano-Martínez, M.; Culver, Melanie

    2014-01-01

    We characterized 22 novel microsatellite loci in the two-spotted octopus Octopus bimaculatus using 454 pyrosequencing reads. All loci were polymorphic and will be used in studies of marine connectivity aimed at increasing sustainability of the resource. The mean number alleles per locus was 13.09 (range 7–19) and observed heterozygosities ranged from 0.50 to 1.00. Four loci pairs were linked and three deviated from Hardy–Weinberg equilibrium. Eighteen and 12 loci were polymorphic in Octopus bimaculoides and Octopus hubbsorum, respectively.

  6. Characterization of ten microsatellite loci in midget faded rattlesnake (Crotalus oreganus concolor)

    Science.gov (United States)

    Oyler-McCance, Sara J.; Parker, Joshua M.

    2010-01-01

    Primers for 10 microsatellite loci were developed for midget faded rattlesnake (Crotalus oreganus concolor), a small bodied subspecies of the Western Rattlesnake, which is found in the Colorado Plateau of eastern Utah, western Colorado and southwestern Wyoming. In a screen of 23 individuals from the most northern portion of the subspecies range in southwestern Wyoming, the 10 loci were found to have levels of variability ranging from 4 to 11 alleles. No loci were found to be linked, although one locus revealed significant departures from Hardy–Weinberg equilibrium. These microsatellite loci will be applicable for population genetic analyses, which will ultimately aid in management efforts for this rare subspecies of rattlesnake.

  7. PERMANENT GENETIC RESOURCES: Isolation and characterization of microsatellite loci from the Arctic cisco (Coregonus autumnalis).

    Science.gov (United States)

    Ramey, A; Graziano, S L; Nielsen, J L

    2008-03-01

    Eight polymorphic microsatellite loci were isolated and characterized for the Arctic cisco, Coregonus autumnalis. Loci were evaluated in 21 samples from the Colville River subsistence fishery. The number of alleles per locus ranged from two to 18. Observed heterozygosity of loci varied from 0.10 to 1.00, and expected heterozygosity ranged from 0.09 to 0.92. All eight microsatellite markers were in Hardy-Weinberg equilibrium. The loci presented here will be useful in describing population structure and exploring populations of origin for Arctic cisco. © 2007 Blackwell Publishing Ltd No claim to original US government works.

  8. Isolation and characterization of microsatellite loci from the Arctic cisco (Coregonus autumnalis)

    Science.gov (United States)

    Ramey, A.; Graziano, S.L.; Nielsen, J.L.

    2008-01-01

    Eight polymorphic microsatellite loci were isolated and characterized for the Arctic cisco, Coregonus autumnalis. Loci were evaluated in 21 samples from the Colville River subsistence fishery. The number of alleles per locus ranged from two to 18. Observed heterozygosity of loci varied from 0.10 to 1.00, and expected heterozygosity ranged from 0.09 to 0.92. All eight microsatellite markers were in Hardy-Weinberg equilibrium. The loci presented here will be useful in describing population structure and exploring populations of origin for Arctic cisco. ?? 2007 Blackwell Publishing Ltd.

  9. Community Structure of Lithotrophically-Driven Hydrothermal Microbial Mats from the Mariana Arc and Back-Arc

    Directory of Open Access Journals (Sweden)

    Kevin W. Hager

    2017-08-01

    Full Text Available The Mariana region exhibits a rich array of hydrothermal venting conditions in a complex geological setting, which provides a natural laboratory to study the influence of local environmental conditions on microbial community structure as well as large-scale patterns in microbial biogeography. We used high-throughput amplicon sequencing of the bacterial small subunit (SSU rRNA gene from 22 microbial mats collected from four hydrothermally active locations along the Mariana Arc and back-arc to explore the structure of lithotrophically-based microbial mat communities. The vent effluent was classified as iron- or sulfur-rich corresponding with two distinct community types, dominated by either Zetaproteobacteria or Epsilonproteobacteria, respectively. The Zetaproteobacterial-based communities had the highest richness and diversity, which supports the hypothesis that Zetaproteobacteria function as ecosystem engineers creating a physical habitat within a chemical environment promoting enhanced microbial diversity. Gammaproteobacteria were also high in abundance within the iron-dominated mats and some likely contribute to primary production. In addition, we also compare sampling scale, showing that bulk sampling of microbial mats yields higher diversity than micro-scale sampling. We present a comprehensive analysis and offer new insights into the community structure and diversity of lithotrophically-driven microbial mats from a hydrothermal region associated with high microbial biodiversity. Our study indicates an important functional role of for the Zetaproteobacteria altering the mat habitat and enhancing community interactions and complexity.

  10. Expansion rate and geometry of floating vegetation mats on the margins of thermokarst lakes, northern Seward Peninsula, Alaska, USA

    Science.gov (United States)

    Parsekian, A.D.; Jones, Benjamin M.; Jones, M.; Grosse, G.; Walter, Anthony K.M.; Slater, L.

    2011-01-01

    Investigations on the northern Seward Peninsula in Alaska identified zones of recent (<50years) permafrost collapse that led to the formation of floating vegetation mats along thermokarst lake margins. The occurrence of floating vegetation mat features indicates rapid degradation of near-surface permafrost and lake expansion. This paper reports on the recent expansion of these collapse features and their geometry is determined using geophysical and remote sensing measurements. The vegetation mats were observed to have an average thickness of 0.57m and petrophysical modeling indicated that gas content of 1.5-5% enabled floatation above the lake surface. Furthermore, geophysical investigation provides evidence that the mats form by thaw and subsidence of the underlying permafrost rather than terrestrialization. The temperature of the water below a vegetation mat was observed to remain above freezing late in the winter. Analysis of satellite and aerial imagery indicates that these features have expanded at maximum rates of 1-2myr-1 over a 56year period. Including the spatial coverage of floating 'thermokarst mats' increases estimates of lake area by as much as 4% in some lakes. ?? 2011 John Wiley & Sons, Ltd.

  11. Multifunctional ZnO/Nylon 6 nanofiber mats by an electrospinning-electrospraying hybrid process for use in protective applications

    Energy Technology Data Exchange (ETDEWEB)

    Vitchuli, Narendiran; Shi Quan; McCord, Marian; Zhang Xiangwu [Fiber and Polymer Science Program, Department of Textile Engineering, Chemistry and Science, North Carolina State University, Raleigh, NC 27695-8301 (United States); Nowak, Joshua; Bourham, Mohamed [Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27695-7909 (United States); Kay, Kathryn [Department of Microbiology, North Carolina State University, Raleigh, NC 27695-7610 (United States); Caldwell, Jane M; Breidt, Frederick, E-mail: bourham@ncsu.edu, E-mail: mmccord@ncsu.edu, E-mail: xiangwu_zhang@ncsu.edu [Department of Food Science, North Carolina Agricultural Research Service, North Carolina State University, Raleigh, NC 27695-7624 (United States)

    2011-10-15

    ZnO/Nylon 6 nanofiber mats were prepared by an electrospinning-electrospraying hybrid process in which ZnO nanoparticles were dispersed on the surface of Nylon 6 nanofibers without becoming completely embedded. The prepared ZnO/Nylon 6 nanofiber mats were evaluated for their abilities to kill bacteria or inhibit their growth and to catalytically detoxify chemicals. Results showed that these ZnO/Nylon 6 nanofiber mats had excellent antibacterial efficiency (99.99%) against both the Gram-negative Escherichia coli and Gram-positive Bacillus cereus bacteria. In addition, they exhibited good detoxifying efficiency (95%) against paraoxon, a simulant of highly toxic chemicals. ZnO/Nylon 6 nanofiber mats were also deposited onto nylon/cotton woven fabrics and the nanofiber mats did not significantly affect the moisture vapor transmission rates and air permeability values of the fabrics. Therefore, ZnO/Nylon 6 nanofiber mats prepared by the electrospinning-electrospraying hybrid process are promising material candidates for protective applications.

  12. Multifunctional ZnO/Nylon 6 nanofiber mats by an electrospinning–electrospraying hybrid process for use in protective applications

    Directory of Open Access Journals (Sweden)

    Narendiran Vitchuli, Quan Shi, Joshua Nowak, Kathryn Kay, Jane M Caldwell, Frederick Breidt, Mohamed Bourham, Marian McCord and Xiangwu Zhang

    2011-01-01

    Full Text Available ZnO/Nylon 6 nanofiber mats were prepared by an electrospinning–electrospraying hybrid process in which ZnO nanoparticles were dispersed on the surface of Nylon 6 nanofibers without becoming completely embedded. The prepared ZnO/Nylon 6 nanofiber mats were evaluated for their abilities to kill bacteria or inhibit their growth and to catalytically detoxify chemicals. Results showed that these ZnO/Nylon 6 nanofiber mats had excellent antibacterial efficiency (99.99% against both the Gram-negative Escherichia coli and Gram-positive Bacillus cereus bacteria. In addition, they exhibited good detoxifying efficiency (95% against paraoxon, a simulant of highly toxic chemicals. ZnO/Nylon 6 nanofiber mats were also deposited onto nylon/cotton woven fabrics and the nanofiber mats did not significantly affect the moisture vapor transmission rates and air permeability values of the fabrics. Therefore, ZnO/Nylon 6 nanofiber mats prepared by the electrospinning–electrospraying hybrid process are promising material candidates for protective applications.

  13. Bacterial and archaeal diversity in two hot spring microbial mats from the geothermal region of Tengchong, China.

    Science.gov (United States)

    Pagaling, Eulyn; Grant, William D; Cowan, Don A; Jones, Brian E; Ma, Yanhe; Ventosa, Antonio; Heaphy, Shaun

    2012-07-01

    We investigated the bacterial and archaeal diversity in two hot spring microbial mats from the geothermal region of Tengchong in the Yunnan Province, China, using direct molecular analyses. The Langpu (LP) laminated mat was found by the side of a boiling pool with temperature of 60-65 °C and a pH of 8.5, while the Tengchong (TC) streamer mat consisted of white streamers in a slightly acidic (pH 6.5) hot pool outflow with a temperature of 72 °C. Four 16S rRNA gene clone libraries were constructed and restriction enzyme analysis of the inserts was used to identify unique sequences and clone frequencies. From almost 200 clones screened, 55 unique sequences were retrieved. Phylogenetic analysis showed that the LP mat consisted of a diverse bacterial population [Cyanobacteria, Chloroflexi, Chlorobia, Nitrospirae, 'Deinococcus-Thermus', Proteobacteria (alpha, beta and delta subdivisions), Firmicutes, Bacteroidetes and Actinobacteria], while the archaeal population was dominated by methanogenic Euryarchaeota and Crenarchaeota. In contrast, the TC streamer mat consisted of a bacterial population dominated by Aquificae, while the archaeal population also contained Korarchaeota as well as Crenarchaeota and methanogenic Euryarchaeota. These mats harboured clone sequences affiliated to unidentified lineages, suggesting that they are a potential source for discovering novel bacteria and archaea.

  14. Preservation in microbial mats: mineralization by a talc-like phase of a fish embedded in a microbial sarcophagus

    Science.gov (United States)

    Iniesto, Miguel; Zeyen, Nina; López-Archilla, Ana; Bernard, Sylvain; Buscalioni, Ángela; Guerrero, M. Carmen; Benzerara, Karim

    2015-09-01

    Microbial mats have been repeatedly suggested to promote early fossilization of macroorganisms. Yet, experimental simulations of this process remain scarce. Here, we report results of 5 year-long experiments performed onfish carcasses to document the influence of microbial mats on mineral precipitation during early fossilization. Carcasses were initially placed on top of microbial mats. After two weeks, fishes became coated by the mats forming a compact sarcophagus, which modified the microenvironment close to the corpses. Our results showed that these conditions favoured the precipitation of a poorly crystalline silicate phase rich in magnesium. This talc-like mineral phase has been detected in three different locations within the carcasses placed in microbial mats for more than 4 years: 1) within inner tissues, colonized by several bacillary cells; 2) at the surface of bones of the upper face of the corpse buried in the mat; and 3) at the surface of several bones such as the dorsal fin which appeared to be gradually replaced by the Mg-silicate phase. This mineral phase has been previously shown to promote bacteria fossilization. Here we provide first experimental evidence that such Mg-rich phase can also be involved in exceptional preservation of animals.

  15. Experimental weed control of Najas marina ssp. intermedia and Elodea nuttallii in lakes using biodegradable jute matting

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    Markus A. Hoffmann

    2013-10-01

    Full Text Available The use of jute matting in managing the invasive aquatic macrophyte species Elodea nuttallii (Planch. H. St. John and Najas marina ssp. intermedia (Wolfg. ex Gorski Casper (Najas intermedia was studied in laboratory experiments and field trials. Four German lakes with predominant population of Najas intermedia or Elodea nuttalli were chosen for the experiment and areas between 150 and 300 m² were covered with jute textile. The effect of the matting on the growth of invasive and non-invasive macrophytes was determined through comparison with control transects. Biodegradable jute matting successfully suppressed the invasive macrophyte Najas intermedia and significantly reduced the growth of Elodea nuttalli in lakes. The results indicate that the capability of the matting to inhibit the growth of Elodea nuttallii and Najas intermedia depends on the mesh size of the jute weaving and that environmental conditions can affect its efficiency. Various indigenous species like Charales or Potamogeton pusillus L. were able to grow through the jute fabric and populate the treated areas. Until the end of the vegetation period, none of the invasive species were able to penetrate the covering and establish a stable population; in fact, in the subsequent year the jute matting affected only the spread of Najas intermedia. Jute matting proved to be an easy-to-use and cheap method to control the growth of Elodea nuttallii and Najas intermedia.

  16. Microbial mat of the thermal springs Kuchiger Republic of Buryatia: species composition, biochemical properties and electrogenic activity in biofuel cell

    Science.gov (United States)

    Aleksandrovich Yuriev, Denis; Viktorovna Zaitseva, Svetlana; Olegovna Zhdanova, Galina; Yurievich Tolstoy, Mikhail; Dondokovna Barkhutova, Darima; Feodorovna Vyatchina, Olga; Yuryevna Konovalova, Elena; Iosifovich Stom, Devard

    2018-02-01

    Electrogenic, molecular and some other properties of a microbial mat isolated from the Kuchiger hot spring (Kurumkansky District, Republic of Buryatia) were studied. Molecular analysis showed that representatives of Proteobacteria (85.5 % of the number of classified bacterial sequences) prevailed in the microbial mat of the Kuchiger springs, among which sulfur bacteria of the genus Thiothrix were the most numerous. In the microbial mat there were bacteria from the families Rhodocyclaceae, Comamonadaceae and Flavobacteriaceae. Phylum Bacteroidetes, Cyanobacteria/Chloroplast, Fusobacteria, Fibrobacteres, Acidobacteria, Chlorobi, Spirochaetes, Verrucomicrobia, Firmicutes, Deinococcus-Thermus, Chloroflexi and Actinobacteria are also noted in the composition of the microbial mat. Under the experimental conditions using Kuchiger-mat 16 as bioagents, glucose and peptone as substrates, the power of BFC was 240 and 221 mW / m2, respectively. When replacing the substrate with sodium acetate, the efficiency of the BFC was reduced by a factor of 10 (20 mW / m2). The prospects of using a microbial mat “Kuchiger-16” as an electrogen in BFC when utilizing alkaline waste water components to generate electricity are discussed.

  17. Les humains sont-ils des entités matérielles ?

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    Tauveron Matthias

    2012-07-01

    Full Text Available Nous étudions la sémantique des noms d’humains dans le lexique français. Dans la littérature, ces noms ont un positionnement indéterminé ou ambigu par rapport au critère concret/abstrait. Ce fait est regrettable car ce critère est considéré comme fondamental. Nous montrons leur positionnement particulier vis-à-vis de ce critère au travers de l’étude de métaphores attestées en corpus dans divers textes écrits. Nous suivons l’optique de Lakoff et Johnson en considérant que la métaphore est un révélateur des catégories de pensée. Dans cet esprit, la question est de savoir si les humains sont des entités matérielles ou non. L’étude est menée sur deux paramètres définitoires des entités matérielles : la masse et la spatialité. Nous apportons des caractérisations lexicales de ces deux propriétés. La masse est envisagée généralement, autour des noms, adjectifs et verbes relevés dans les dictionnaires. Nous proposons une synthèse des divers paramètres dénotant la spatialité dans la littérature, sous la forme de six points indépendants (forme, intérieur/extérieur, sous-parties, changement de posture, localisation, déplacement. L’étude de la spatialité est menée systématiquement dans ces directions grâce à des tests issus des caractérisations lexicales de ces aspects. Les tests font voir que, si les humains sont dotés d’une certaine dimension matérielle (qu’ils partagent ainsi avec les objets concrets, ils ont également au moins trois autres dimensions qui font qu’ils ne se réduisent pas à des objets matériels. Nous montrons ainsi que l’humain est, dans le lexique français, doté d’une multiplicité ontologique : en plus d’une dimension matérielle, il dispose d’une dimension psychologique, une dimension praxéologique et une dimension sociale. De plus, l’étude des métaphores montre que la dimension matérielle est souvent réduite voire anéantie par rapport aux

  18. Chondrichthyans of the San Matías Gulf, Patagonia, Argentina Los condrictios del Golfo San Matías, Patagonia, Argentina

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    María R PERIER

    2011-12-01

    Full Text Available The San Matías Gulf (SMG; 41°- 42° S; 64°- 65° W is the largest gulf in Northern Patagonia, Argentina. Up to date, the chondrichthyan fauna of this area has not been reported. Therefore, the aim of this work is to provide a list with species presence and biological characteristics of the chondrichthyans recorded in SMG during the last 30 years. A total of 13 sharks distributed in 11 families, 19 skates and rays distributed in six families, and one holocephalan have been so far recorded in SMG. From the zoogeographical point of view, this chondrichthyan fauna is a mixed assemblage of species typically found in the Argentinean and Magellanean Provinces. The holocephalan Callorhinchus callorynchus is the most landed chondricthyan of the local fishery. With it, five sharks and seven skates are also exploited.El Golfo San Matías (SMG; 41°- 42° S - 64°-65° O se encuentra ubicado en el norte de la Patagonia, Argentina. Hasta la fecha no se cuentan con reportes de la fauna de condrictios de esta zona. Por lo tanto, el objetivo de este trabajo es proporcionar una lista de la presencia y las características biológicas de los condrictios registrados en el SMG durante los últimos 30 años. Un total de 13 tiburones distribuidos en 11 familias, 19 batoideos distribuidos en seis familias y un holocefalo han sido reportados para la zona. Desde el punto de vista zoogeográfico, el SMG presenta un ensamble de especies pertenecientes a las Provincias Magallánica y Argentina. El holocefalo Callorhinchus callorynchus es el condrictio más desembarcado de la pesquería local. Con menor importancia son explotadas comercialmente, cinco especies de tiburones y siete de rayas.

  19. Multiple loci are associated with white blood cell phenotypes.

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    Michael A Nalls

    2011-06-01

    Full Text Available White blood cell (WBC count is a common clinical measure from complete blood count assays, and it varies widely among healthy individuals. Total WBC count and its constituent subtypes have been shown to be moderately heritable, with the heritability estimates varying across cell types. We studied 19,509 subjects from seven cohorts in a discovery analysis, and 11,823 subjects from ten cohorts for replication analyses, to determine genetic factors influencing variability within the normal hematological range for total WBC count and five WBC subtype measures. Cohort specific data was supplied by the CHARGE, HeamGen, and INGI consortia, as well as independent collaborative studies. We identified and replicated ten associations with total WBC count and five WBC subtypes at seven different genomic loci (total WBC count-6p21 in the HLA region, 17q21 near ORMDL3, and CSF3; neutrophil count-17q21; basophil count- 3p21 near RPN1 and C3orf27; lymphocyte count-6p21, 19p13 at EPS15L1; monocyte count-2q31 at ITGA4, 3q21, 8q24 an intergenic region, 9q31 near EDG2, including three previously reported associations and seven novel associations. To investigate functional relationships among variants contributing to variability in the six WBC traits, we utilized gene expression- and pathways-based analyses. We implemented gene-clustering algorithms to evaluate functional connectivity among implicated loci and showed functional relationships across cell types. Gene expression data from whole blood was utilized to show that significant biological consequences can be extracted from our genome-wide analyses, with effect estimates for significant loci from the meta-analyses being highly corellated with the proximal gene expression. In addition, collaborative efforts between the groups contributing to this study and related studies conducted by the COGENT and RIKEN groups allowed for the examination of effect homogeneity for genome-wide significant associations across

  20. Experimental Studies on Geocells and Mat Systems for Stabilization of Unpaved Shoulders and Temporary Roads

    Science.gov (United States)

    Guo, Jun

    Geosynthetics have been used to improve the performance of geomaterials, especially when weak soil exists in roadway applications. In this study, two types of geosynthetic materials, geocell and a mat system, were studied for their applications for unpaved roads and shoulders. The study of geocell was focused on its application for unpaved shoulders. The ability of geocell to improve different geomaterials over intermediate strength subgrade and its possible effect on vegetation were investigated. The study of the mat system was focused on investigating the performance of the mat system over soft and intermediate subgrade with different strengths under cyclic loading to simulate temporary roadway conditions. In the study of geocell for the application for unpaved shoulders, six large scale plate loading tests were conducted on a single type of geocell on target 5% CBR subgrade to investigate the benefits of geocell reinforcement on different base course and topsoil combinations. Different base course and topsoil combinations were investigated including: 200-mm thick unreinforced aggregate, 200-mm thick soil-aggregate mixture (50% aggregate and 50% top soil) with and without geocell reinforcement, 200-mm thick geocell-reinforced topsoil, 50-mm thick aggregate over 150-mm soil-aggregate mixture (50% aggregate and 50% top soil), and 50-mm thick top soil over 150-mm thick geocell-reinforced soil-aggregate mixture (50% aggregate and 50% top soil). Earth pressure cells were install at the interface between subgrade and base course to monitor the load distribution. The cyclic plate loading tests showed that geocell effectively reduced the permanent deformation and the geocell-reinforced soil-aggregate mixture slightly outperformed the unreinforced aggregate at the same thickness. The plate loading tests also suggested the topsoil cover resulted in large permanent deformations. A one-year long outdoor field vegetation test was conducted on base courses with different