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Sample records for sequences demonstrate latitudinal

  1. Optic nerve injury demonstrated by MRI with STIR sequences

    International Nuclear Information System (INIS)

    Takehara, S.; Tanaka, T.; Uemura, K.; Shinohara, Y.; Yamamoto, T.; Tokuyama, T.; Satoh, A.

    1994-01-01

    We studied nine patients with optic nerve injury associated with closed head trauma by magnetic resonance imaging (MRI) with short inversion time inversion recovery (STIR) sequences on 11 occasions from 4 days to 14 years after the injury: three studies were within 17 days and eight over 4 months to 14 years. MRI revealed abnormal high signal in 10 of the 11 injured nerves. MRI 4 days after the injury showed no abnormality. (orig.)

  2. When What's Inside Counts: Sequence of Demonstrated Actions Affects Preschooler's Categorization by Nonobvious Properties

    Science.gov (United States)

    Yu, Yue; Kushnir, Tamar

    2016-01-01

    This study explores the role of a particular social cue--the "sequence" of demonstrated actions and events--in preschooler's categorization. A demonstrator sorted objects that varied on both a surface feature (color) and a nonobvious property (sound made when shaken). Children saw a sequence of actions in which the nonobvious property…

  3. International Interlaboratory Digital PCR Study Demonstrating High Reproducibility for the Measurement of a Rare Sequence Variant.

    Science.gov (United States)

    Whale, Alexandra S; Devonshire, Alison S; Karlin-Neumann, George; Regan, Jack; Javier, Leanne; Cowen, Simon; Fernandez-Gonzalez, Ana; Jones, Gerwyn M; Redshaw, Nicholas; Beck, Julia; Berger, Andreas W; Combaret, Valérie; Dahl Kjersgaard, Nina; Davis, Lisa; Fina, Frederic; Forshew, Tim; Fredslund Andersen, Rikke; Galbiati, Silvia; González Hernández, Álvaro; Haynes, Charles A; Janku, Filip; Lacave, Roger; Lee, Justin; Mistry, Vilas; Pender, Alexandra; Pradines, Anne; Proudhon, Charlotte; Saal, Lao H; Stieglitz, Elliot; Ulrich, Bryan; Foy, Carole A; Parkes, Helen; Tzonev, Svilen; Huggett, Jim F

    2017-02-07

    This study tested the claim that digital PCR (dPCR) can offer highly reproducible quantitative measurements in disparate laboratories. Twenty-one laboratories measured four blinded samples containing different quantities of a KRAS fragment encoding G12D, an important genetic marker for guiding therapy of certain cancers. This marker is challenging to quantify reproducibly using quantitative PCR (qPCR) or next generation sequencing (NGS) due to the presence of competing wild type sequences and the need for calibration. Using dPCR, 18 laboratories were able to quantify the G12D marker within 12% of each other in all samples. Three laboratories appeared to measure consistently outlying results; however, proper application of a follow-up analysis recommendation rectified their data. Our findings show that dPCR has demonstrable reproducibility across a large number of laboratories without calibration. This could enable the reproducible application of molecular stratification to guide therapy and, potentially, for molecular diagnostics.

  4. Sample sequencing of vascular plants demonstrates widespread conservation and divergence of microRNAs.

    Science.gov (United States)

    Chávez Montes, Ricardo A; de Fátima Rosas-Cárdenas, Flor; De Paoli, Emanuele; Accerbi, Monica; Rymarquis, Linda A; Mahalingam, Gayathri; Marsch-Martínez, Nayelli; Meyers, Blake C; Green, Pamela J; de Folter, Stefan

    2014-04-23

    Small RNAs are pivotal regulators of gene expression that guide transcriptional and post-transcriptional silencing mechanisms in eukaryotes, including plants. Here we report a comprehensive atlas of sRNA and miRNA from 3 species of algae and 31 representative species across vascular plants, including non-model plants. We sequence and quantify sRNAs from 99 different tissues or treatments across species, resulting in a data set of over 132 million distinct sequences. Using miRBase mature sequences as a reference, we identify the miRNA sequences present in these libraries. We apply diverse profiling methods to examine critical sRNA and miRNA features, such as size distribution, tissue-specific regulation and sequence conservation between species, as well as to predict putative new miRNA sequences. We also develop database resources, computational analysis tools and a dedicated website, http://smallrna.udel.edu/. This study provides new insights on plant sRNAs and miRNAs, and a foundation for future studies.

  5. Genome Sequence of Enterococcus faecium Strain ICIS 96 Demonstrating Intermicrobial Antagonism Associated with Bacteriocin Production.

    Science.gov (United States)

    Pashkova, Tatiana M; Vasilchenko, Alexey S; Khlopko, Yuriy A; Kochkina, Elena E; Kartashova, Olga L; Sycheva, Maria V

    2018-03-08

    We report here the complete genome sequence of Enterococcus faecium strain ICIS 96, which was isolated from the feces of a horse. Bacteriological characterization of strain ICIS 96 revealed the absence of pathogenicity factors, while its spectrum of antagonistic activity was found to be broad, having activities associated with both Gram-positive and Gram-negative bacteria. Analysis of the E. faecium ICIS 96 genome revealed five genes associated with antimicrobial activity (enterocin [ent] A, ent B, lactobin A/cerein 7b, and ent L50 A/B). No genes that correlate with human pathogenicity were identified. Copyright © 2018 Pashkova et al.

  6. Latitudinal variation of the solar photospheric intensity

    OpenAIRE

    Rast, Mark P.; Ortiz, Ada; Meisner, Randle W.

    2007-01-01

    We have examined images from the Precision Solar Photometric Telescope (PSPT) at the Mauna Loa Solar Observatory (MLSO) in search of latitudinal variation in the solar photospheric intensity. Along with the expected brightening of the solar activity belts, we have found a weak enhancement of the mean continuum intensity at polar latitudes (continuum intensity enhancement $\\sim0.1 - 0.2%$ corresponding to a brightness temperature enhancement of $\\sim2.5{\\rm K}$). This appears to be thermal in ...

  7. Latitudinal Variation of Germane in Jovian Atmosphere

    Science.gov (United States)

    Hyder, A.; Lunine, J. I.; Wang, D.

    2017-12-01

    Wang et al (2016) presented a chemical-dynamical model for Jupiter's atmosphere that predicted abundances of Germane and other disequilibrium species as a function of latitude, under the assumption that only vertical transport is relevant and no horizontal advection occurs. The model disagrees with the latitudinal distributions derived from high-resolution spectral data acquired from the CRIRES instrument at the VLT as described in Giles et al. 2017. Wang et al. 2016 predicts a maximum molar abundance of Germane at (0.7±0.2) ppb with depletion at higher latitudes, while Giles et al. 2017 predicts a constant molar abundance of Germane at 0.58 ppb with no depletion. We explore an empirical horizontal term for the diffusive transport coefficient as a function of latitude, which does not produce a satisfactory result unless highly arbitrary variations of the vertical eddy mixing term as a function of latitude are imposed. We therefore also explore a horizontal wind from the equator that produces a constant latitudinal profile by transporting Germane-rich gas to the poles, effectively producing a Hadley cell. References: Giles, R. S., Fletcher, L. N., & Irwin, P. G. (2017). Latitudinal variability in Jupiter's tropospheric disequilibrium species: GeH 4, AsH 3 and PH 3. Icarus, 289, 254-269. Wang, D., Lunine, J.I., Mousis, O., 2016. Modeling the disequilibrium species for Jupiter and Saturn: implications for Juno and Saturn entry probe. Icarus 276, 21-38.

  8. Cloning and sequence analysis demonstrate the chromate reduction ability of a novel chromate reductase gene from Serratia sp.

    Science.gov (United States)

    Deng, Peng; Tan, Xiaoqing; Wu, Ying; Bai, Qunhua; Jia, Yan; Xiao, Hong

    2015-03-01

    The ChrT gene encodes a chromate reductase enzyme which catalyzes the reduction of Cr(VI). The chromate reductase is also known as flavin mononucleotide (FMN) reductase (FMN_red). The aim of the present study was to clone the full-length ChrT DNA from Serratia sp. CQMUS2 and analyze the deduced amino acid sequence and three-dimensional structure. The putative ChrT gene fragment of Serratia sp. CQMUS2 was isolated by polymerase chain reaction (PCR), according to the known FMN_red gene sequence from Serratia sp. AS13. The flanking sequences of the ChrT gene were obtained by high efficiency TAIL-PCR, while the full-length gene of ChrT was cloned in Escherichia coli for subsequent sequencing. The nucleotide sequence of ChrT was submitted onto GenBank under the accession number, KF211434. Sequence analysis of the gene and amino acids was conducted using the Basic Local Alignment Search Tool, and open reading frame (ORF) analysis was performed using ORF Finder software. The ChrT gene was found to be an ORF of 567 bp that encodes a 188-amino acid enzyme with a calculated molecular weight of 20.4 kDa. In addition, the ChrT protein was hypothesized to be an NADPH-dependent FMN_red and a member of the flavodoxin-2 superfamily. The amino acid sequence of ChrT showed high sequence similarity to the FMN reductase genes of Klebsiella pneumonia and Raoultella ornithinolytica , which belong to the flavodoxin-2 superfamily. Furthermore, ChrT was shown to have a 85.6% similarity to the three-dimensional structure of Escherichia coli ChrR, sharing four common enzyme active sites for chromate reduction. Therefore, ChrT gene cloning and protein structure determination demonstrated the ability of the gene for chromate reduction. The results of the present study provide a basis for further studies on ChrT gene expression and protein function.

  9. Cloning and sequence analysis demonstrate the chromate reduction ability of a novel chromate reductase gene from Serratia sp

    Science.gov (United States)

    DENG, PENG; TAN, XIAOQING; WU, YING; BAI, QUNHUA; JIA, YAN; XIAO, HONG

    2015-01-01

    The ChrT gene encodes a chromate reductase enzyme which catalyzes the reduction of Cr(VI). The chromate reductase is also known as flavin mononucleotide (FMN) reductase (FMN_red). The aim of the present study was to clone the full-length ChrT DNA from Serratia sp. CQMUS2 and analyze the deduced amino acid sequence and three-dimensional structure. The putative ChrT gene fragment of Serratia sp. CQMUS2 was isolated by polymerase chain reaction (PCR), according to the known FMN_red gene sequence from Serratia sp. AS13. The flanking sequences of the ChrT gene were obtained by high efficiency TAIL-PCR, while the full-length gene of ChrT was cloned in Escherichia coli for subsequent sequencing. The nucleotide sequence of ChrT was submitted onto GenBank under the accession number, KF211434. Sequence analysis of the gene and amino acids was conducted using the Basic Local Alignment Search Tool, and open reading frame (ORF) analysis was performed using ORF Finder software. The ChrT gene was found to be an ORF of 567 bp that encodes a 188-amino acid enzyme with a calculated molecular weight of 20.4 kDa. In addition, the ChrT protein was hypothesized to be an NADPH-dependent FMN_red and a member of the flavodoxin-2 superfamily. The amino acid sequence of ChrT showed high sequence similarity to the FMN reductase genes of Klebsiella pneumonia and Raoultella ornithinolytica, which belong to the flavodoxin-2 superfamily. Furthermore, ChrT was shown to have a 85.6% similarity to the three-dimensional structure of Escherichia coli ChrR, sharing four common enzyme active sites for chromate reduction. Therefore, ChrT gene cloning and protein structure determination demonstrated the ability of the gene for chromate reduction. The results of the present study provide a basis for further studies on ChrT gene expression and protein function. PMID:25667630

  10. Temporal sequence learning in winner-take-all networks of spiking neurons demonstrated in a brain-based device.

    Science.gov (United States)

    McKinstry, Jeffrey L; Edelman, Gerald M

    2013-01-01

    Animal behavior often involves a temporally ordered sequence of actions learned from experience. Here we describe simulations of interconnected networks of spiking neurons that learn to generate patterns of activity in correct temporal order. The simulation consists of large-scale networks of thousands of excitatory and inhibitory neurons that exhibit short-term synaptic plasticity and spike-timing dependent synaptic plasticity. The neural architecture within each area is arranged to evoke winner-take-all (WTA) patterns of neural activity that persist for tens of milliseconds. In order to generate and switch between consecutive firing patterns in correct temporal order, a reentrant exchange of signals between these areas was necessary. To demonstrate the capacity of this arrangement, we used the simulation to train a brain-based device responding to visual input by autonomously generating temporal sequences of motor actions.

  11. TRX-LOGOS - a graphical tool to demonstrate DNA information content dependent upon backbone dynamics in addition to base sequence.

    Science.gov (United States)

    Fortin, Connor H; Schulze, Katharina V; Babbitt, Gregory A

    2015-01-01

    It is now widely-accepted that DNA sequences defining DNA-protein interactions functionally depend upon local biophysical features of DNA backbone that are important in defining sites of binding interaction in the genome (e.g. DNA shape, charge and intrinsic dynamics). However, these physical features of DNA polymer are not directly apparent when analyzing and viewing Shannon information content calculated at single nucleobases in a traditional sequence logo plot. Thus, sequence logos plots are severely limited in that they convey no explicit information regarding the structural dynamics of DNA backbone, a feature often critical to binding specificity. We present TRX-LOGOS, an R software package and Perl wrapper code that interfaces the JASPAR database for computational regulatory genomics. TRX-LOGOS extends the traditional sequence logo plot to include Shannon information content calculated with regard to the dinucleotide-based BI-BII conformation shifts in phosphate linkages on the DNA backbone, thereby adding a visual measure of intrinsic DNA flexibility that can be critical for many DNA-protein interactions. TRX-LOGOS is available as an R graphics module offered at both SourceForge and as a download supplement at this journal. To demonstrate the general utility of TRX logo plots, we first calculated the information content for 416 Saccharomyces cerevisiae transcription factor binding sites functionally confirmed in the Yeastract database and matched to previously published yeast genomic alignments. We discovered that flanking regions contain significantly elevated information content at phosphate linkages than can be observed at nucleobases. We also examined broader transcription factor classifications defined by the JASPAR database, and discovered that many general signatures of transcription factor binding are locally more information rich at the level of DNA backbone dynamics than nucleobase sequence. We used TRX-logos in combination with MEGA 6.0 software

  12. Latitudinal shifts of introduced species: possible causes and implications

    Science.gov (United States)

    Qinfeng Guo; Dov F. Sax; Hong Qian; Regan Early

    2012-01-01

    This study aims to document shifts in the latitudinal distributions of non-native species relative to their own native distributions and to discuss possible causes and implications of these shifts. We used published and newly compiled data on intercontinentally introduced birds, mammals and plants. We found strong correlations between the latitudinal distributions...

  13. The Effect of Latitudinal Variation on Shrimp Reproductive Strategies.

    Science.gov (United States)

    van de Kerk, Madelon; Jones Littles, Chanda; Saucedo, Omar; Lorenzen, Kai

    2016-01-01

    Reproductive strategies comprise the timing and frequency of reproductive events and the number of offspring per reproductive event, depending on factors such as climate conditions. Therefore, species that exhibit plasticity in the allocation of reproductive effort can alter their behavior in response to climate change. Studying how the reproductive strategy of species varies along the latitudinal gradient can help us understand and predict how they will respond to climate change. We investigated the effects of the temporal allocation of reproductive effort on the population size of brown shrimp (Farfantepenaeus aztecus) along a latitudinal gradient. Multiple shrimp species exhibit variation in their reproductive strategies, and given the economic importance of brown shrimp to the commercial fishing sector of the Unites States, changes in the timing of their reproduction could have significant economic and social consequences. We used a stage-based, density-dependent matrix population model tailored to the life history of brown shrimp. Shrimp growth rates and environmental carrying capacity were varied based on the seasonal climate conditions at different latitudes, and we estimated the population size at equilibrium. The length of the growing season increased with decreasing latitude and the reproductive strategy leading to the highest population size changed from one annual birth pulse with high reproductive output to continuous low-output reproduction. Hence, our model confirms the classical paradigm of continuous reproduction at low latitudes, with increased seasonality of the breeding period towards the poles. Our results also demonstrate the potential for variation in climate to affect the optimal reproductive strategy for achieving maximum population sizes. Certainly, understanding these dynamics may inform more comprehensive management strategies for commercially important species like brown shrimp.

  14. The Effect of Latitudinal Variation on Shrimp Reproductive Strategies.

    Directory of Open Access Journals (Sweden)

    Madelon van de Kerk

    Full Text Available Reproductive strategies comprise the timing and frequency of reproductive events and the number of offspring per reproductive event, depending on factors such as climate conditions. Therefore, species that exhibit plasticity in the allocation of reproductive effort can alter their behavior in response to climate change. Studying how the reproductive strategy of species varies along the latitudinal gradient can help us understand and predict how they will respond to climate change. We investigated the effects of the temporal allocation of reproductive effort on the population size of brown shrimp (Farfantepenaeus aztecus along a latitudinal gradient. Multiple shrimp species exhibit variation in their reproductive strategies, and given the economic importance of brown shrimp to the commercial fishing sector of the Unites States, changes in the timing of their reproduction could have significant economic and social consequences. We used a stage-based, density-dependent matrix population model tailored to the life history of brown shrimp. Shrimp growth rates and environmental carrying capacity were varied based on the seasonal climate conditions at different latitudes, and we estimated the population size at equilibrium. The length of the growing season increased with decreasing latitude and the reproductive strategy leading to the highest population size changed from one annual birth pulse with high reproductive output to continuous low-output reproduction. Hence, our model confirms the classical paradigm of continuous reproduction at low latitudes, with increased seasonality of the breeding period towards the poles. Our results also demonstrate the potential for variation in climate to affect the optimal reproductive strategy for achieving maximum population sizes. Certainly, understanding these dynamics may inform more comprehensive management strategies for commercially important species like brown shrimp.

  15. Molecular evolution and the latitudinal biodiversity gradient.

    Science.gov (United States)

    Dowle, E J; Morgan-Richards, M; Trewick, S A

    2013-06-01

    Species density is higher in the tropics (low latitude) than in temperate regions (high latitude) resulting in a latitudinal biodiversity gradient (LBG). The LBG must be generated by differential rates of speciation and/or extinction and/or immigration among regions, but the role of each of these processes is still unclear. Recent studies examining differences in rates of molecular evolution have inferred a direct link between rate of molecular evolution and rate of speciation, and postulated these as important drivers of the LBG. Here we review the molecular genetic evidence and examine the factors that might be responsible for differences in rates of molecular evolution. Critical to this is the directionality of the relationship between speciation rates and rates of molecular evolution.

  16. Multilocus sequence typing and rtxA toxin gene sequencing analysis of Kingella kingae isolates demonstrates genetic diversity and international clones.

    Directory of Open Access Journals (Sweden)

    Romain Basmaci

    Full Text Available BACKGROUND: Kingella kingae, a normal component of the upper respiratory flora, is being increasingly recognized as an important invasive pathogen in young children. Genetic diversity of this species has not been studied. METHODS: We analyzed 103 strains from different countries and clinical origins by a new multilocus sequence-typing (MLST schema. Putative virulence gene rtxA, encoding an RTX toxin, was also sequenced, and experimental virulence of representative strains was assessed in a juvenile-rat model. RESULTS: Thirty-six sequence-types (ST and nine ST-complexes (STc were detected. The main STc 6, 14 and 23 comprised 23, 17 and 20 strains respectively, and were internationally distributed. rtxA sequencing results were mostly congruent with MLST, and showed horizontal transfer events. Of interest, all members of the distantly related ST-6 (n = 22 and ST-5 (n = 4 harboured a 33 bp duplication or triplication in their rtxA sequence, suggesting that this genetic trait arose through selective advantage. The animal model revealed significant differences in virulence among strains of the species. CONCLUSION: MLST analysis reveals international spread of ST-complexes and will help to decipher acquisition and evolution of virulence traits and diversity of pathogenicity among K. kingae strains, for which an experimental animal model is now available.

  17. A Latitudinal Metabolome of the Atlantic Ocean

    Science.gov (United States)

    Johnson, W.; Kido Soule, M. C.; Longnecker, K.; Kujawinski, E. B.

    2016-02-01

    Microbial consortia function via the exchange and transformation of small organic molecules or metabolites. These metabolites make up a pool of rapidly cycling organic matter in the ocean that is challenging to characterize due to its low concentrations. We seek to determine the distribution of these molecules and the factors that shape their abundance and flux. Through measurements of the abundance of a core set of metabolites, including nucleic acids, amino acids, sugars, vitamins, and signaling molecules, we gain a real-time snapshot of microbial activity. We used a targeted metabolomics technique to profile metabolite abundance in particulate and dissolved organic matter extracts collected from a 14,000 km transect running from 38˚S to 55˚N in the Western Atlantic Ocean. This extensive dataset is the first of its kind in the Atlantic Ocean and allows us to explore connections among metabolites as well as latitudinal trends in metabolite abundance. We found changes in the intracellular abundance of certain metabolites between low and high nutrient regions and a wide distribution of certain dissolved vitamins in the surface ocean. These measurements give us baseline data on the distribution of these metabolites and allow us to extend our understanding of microbial community activity in different regions of the ocean.

  18. Potential latitudinal variation in orodigestive tract cancers in Africa

    African Journals Online (AJOL)

    A latitudinal relationship has been found between the ... Africa should be focused in terms of regional variations to make best use of the fiscal allocation ..... Squamous cell carcinoma of the upper aerodigestive tract: Precursors and problematic.

  19. Latitudinal and longitudinal variation in aerosol characteristics from ...

    Indian Academy of Sciences (India)

    The physical and chemical properties of aerosols are strong ... Keywords. Aerosol optical characteristics; latitudinal and longitudinal variations; Bay of Bengal; Arabian Sea; pre- ...... of global sources of atmospheric soil dust identified with the ...

  20. Latitudinal diversity gradients in Mesozoic non-marine turtles

    Science.gov (United States)

    Nicholson, David B.; Holroyd, Patricia A.; Valdes, Paul; Barrett, Paul M.

    2016-11-01

    The latitudinal biodiversity gradient (LBG)-the pattern of increasing taxonomic richness with decreasing latitude-is prevalent in the structure of the modern biota. However, some freshwater taxa show peak richness at mid-latitudes; for example, extant Testudines (turtles, terrapins and tortoises) exhibit their greatest diversity at 25° N, a pattern sometimes attributed to recent bursts of climatically mediated species diversification. Here, we test whether this pattern also characterizes the Mesozoic distribution of turtles, to determine whether it was established during either their initial diversification or as a more modern phenomenon. Using global occurrence data for non-marine testudinate genera, we find that subsampled richness peaks at palaeolatitudes of 15-30° N in the Jurassic, 30-45° N through the Cretaceous to the Campanian, and from 30° to 60° N in the Maastrichtian. The absence of a significant diversity peak in southern latitudes is consistent with results from climatic models and turtle niche modelling that demonstrate a dearth of suitable turtle habitat in Gondwana during the Jurassic and Late Cretaceous. Our analyses confirm that the modern testudinate LBG has a deep-time origin and further demonstrate that LBGs are not always expressed as a smooth, equator-to-pole distribution.

  1. Phylogenetic and functional analysis of metagenome sequence from high-temperature archaeal habitats demonstrate linkages between metabolic potential and geochemistry

    Directory of Open Access Journals (Sweden)

    William P. Inskeep

    2013-05-01

    Full Text Available Geothermal habitats in Yellowstone National Park (YNP provide an unparalled opportunity to understand the environmental factors that control the distribution of archaea in thermal habitats. Here we describe, analyze and synthesize metagenomic and geochemical data collected from seven high-temperature sites that contain microbial communities dominated by archaea relative to bacteria. The specific objectives of the study were to use metagenome sequencing to determine the structure and functional capacity of thermophilic archaeal-dominated microbial communities across a pH range from 2.5 to 6.4 and to discuss specific examples where the metabolic potential correlated with measured environmental parameters and geochemical processes occurring in situ. Random shotgun metagenome sequence (~40-45 Mbase Sanger sequencing per site was obtained from environmental DNA extracted from high-temperature sediments and/or microbial mats and subjected to numerous phylogenetic and functional analyses. Analysis of individual sequences (e.g., MEGAN and G+C content and assemblies from each habitat type revealed the presence of dominant archaeal populations in all environments, 10 of whose genomes were largely reconstructed from the sequence data. Analysis of protein family occurrence, particularly of those involved in energy conservation, electron transport and autotrophic metabolism, revealed significant differences in metabolic strategies across sites consistent with differences in major geochemical attributes (e.g., sulfide, oxygen, pH. These observations provide an ecological basis for understanding the distribution of indigenous archaeal lineages across high temperature systems of YNP.

  2. Latitudinal gradients in degradation of marine dissolved organic carbon.

    Directory of Open Access Journals (Sweden)

    Carol Arnosti

    Full Text Available Heterotrophic microbial communities cycle nearly half of net primary productivity in the ocean, and play a particularly important role in transformations of dissolved organic carbon (DOC. The specific means by which these communities mediate the transformations of organic carbon are largely unknown, since the vast majority of marine bacteria have not been isolated in culture, and most measurements of DOC degradation rates have focused on uptake and metabolism of either bulk DOC or of simple model compounds (e.g. specific amino acids or sugars. Genomic investigations provide information about the potential capabilities of organisms and communities but not the extent to which such potential is expressed. We tested directly the capabilities of heterotrophic microbial communities in surface ocean waters at 32 stations spanning latitudes from 76°S to 79°N to hydrolyze a range of high molecular weight organic substrates and thereby initiate organic matter degradation. These data demonstrate the existence of a latitudinal gradient in the range of complex substrates available to heterotrophic microbial communities, paralleling the global gradient in bacterial species richness. As changing climate increasingly affects the marine environment, changes in the spectrum of substrates accessible by microbial communities may lead to shifts in the location and rate at which marine DOC is respired. Since the inventory of DOC in the ocean is comparable in magnitude to the atmospheric CO(2 reservoir, such a change could profoundly affect the global carbon cycle.

  3. Latitudinal variation in cranial dimorphism in Macaca fascicularis.

    Science.gov (United States)

    Schillaci, Michael A

    2010-02-01

    This study examines latitudinal and insular variation in the expression of sexual dimorphism in cranial length in three geographical groupings of Macaca fascicularis. In addition, the relationship between cranial length dimorphism (CLD) and sex-specific size is examined. The results of the study identified a significant relationship between CLD and latitude for only one of the three geographic groupings. Sex-specific relationships between cranial length and CLD were detected. The pattern of these relationships varied by geographic grouping. This study is important because it demonstrates that despite very similar levels of CLD in a single primate species, there exists important geographic variability in the correlates of that dimorphism. I suggest that geographically varying ecological factors may influence sex-specific natural selection and the intensity of CLD in M. fascicularis. Gaining a better understanding of this geographical variability will require that future research examines morphological variation, including CLD, within its corresponding ecological and social contexts. Such research should be comparative, and incorporate multiple geographically separated populations with disparate environmental settings.

  4. Latitudinal Gradients in Induced and Constitutive Resistance against Herbivores.

    Science.gov (United States)

    Anstett, Daniel N; Chen, Wen; Johnson, Marc T J

    2016-08-01

    Plants are hypothesized to evolve increased defense against herbivores at lower latitudes, but an increasing number of studies report evidence that contradicts this hypothesis. Few studies have examined the evolution of constitutive and induced resistance along latitudinal gradients. When induction is not considered, underlying patterns of latitudinal clines in resistance can be obscured because plant resistance represents a combination of induced and constitutive resistance, which may show contrasting patterns with latitude. Here, we asked if there are latitudinal gradients in constitutive versus induced resistance by using genotypes of Oenothera biennis (Onagraceae) sampled along an 18° latitudinal gradient. We conducted two bioassay experiments to compare the resistance of plant genotypes against one generalist (Spodoptera exigua) and one specialist (Acanthoscelidius acephalus) herbivore. These insects were assayed on: i) undamaged control plants, ii) plants that had been induced with jasmonic acid, and iii) plants induced with herbivore damage. Additionally, we examined latitudinal gradients of constitutive and induced chemical resistance by measuring the concentrations of total phenolics, the concentration of oxidized phenolics, and the percentage of phenolics that were oxidized. Spodoptera exigua showed lower performance on plants from lower latitudes, whereas A. acephalus showed no latitudinal pattern. Constitutive total phenolics were greater in plants from lower latitudes, but induced plants showed higher total phenolics at higher latitudes. Oxidative activity was greatest at higher latitudes regardless of induction. Overall, both latitude and induction have an impact on different metrics of plant resistance to herbivory. Further studies should consider the effect of induction and herbivore specialization more explicitly, which may help to resolve the controversy in latitudinal gradients in herbivory and defense.

  5. DEMONSTRATION BY MASS-SPECTROMETRY THAT PSEUDO-HEVEIN AND HEVEIN HAVE RAGGED C-TERMINAL SEQUENCES

    NARCIS (Netherlands)

    SOEDJANAATMADJA, UMS; HOFSTEENGE, J; JERONIMUSSTRATINGH, CM; BRUINS, AP; BEINTEMA, JJ

    1994-01-01

    The primary structure of pseudo-hevein, a minor hevein component from the latex of the rubber tree, Hevea brasiliensis, was determined. Six differences with the sequence of the major hevein component were found, one of which is a replacement of tryptophan by tyrosine in the carbohydrate binding

  6. The genetic effects of Late Quaternary climatic changes over a tropical latitudinal gradient: diversification of an Atlantic Forest passerine.

    Science.gov (United States)

    d'Horta, Fernando M; Cabanne, Gustavo S; Meyer, Diogo; Miyaki, Cristina Y

    2011-05-01

    The increase in biodiversity from high to low latitudes is a widely recognized biogeographical pattern. According to the latitudinal gradient hypothesis (LGH), this pattern was shaped by differential effects of Late Quaternary climatic changes across a latitudinal gradient. Here, we evaluate the effects of climatic changes across a tropical latitudinal gradient and its implications to diversification of an Atlantic Forest (AF) endemic passerine. We studied the intraspecific diversification and historical demography of Sclerurus scansor, based on mitochondrial (ND2, ND3 and cytb) and nuclear (FIB7) gene sequences. Phylogenetic analyses recovered three well-supported clades associated with distinct latitudinal zones. Coalescent-based methods were applied to estimate divergence times and changes in effective population sizes. Estimates of divergence times indicate that intraspecific diversification took place during Middle-Late Pleistocene. Distinct demographic scenarios were identified, with the southern lineage exhibiting a clear signature of demographic expansion, while the central one remained more stable. The northern lineage, contrasting with LGH predictions, exhibited a clear sign of a recent bottleneck. Our results suggest that different AF regions reacted distinctly, even in opposite ways, under the same climatic period, producing simultaneously favourable scenarios for isolation and contact among populations. © 2011 Blackwell Publishing Ltd.

  7. Latitudinal migration of sunspots based on the ESAI database

    Science.gov (United States)

    Zhang, Juan; Li, Fu-Yu; Feng, Wen

    2018-01-01

    The latitudinal migration of sunspots toward the equator, which implies there is propagation of the toroidal magnetic flux wave at the base of the solar convection zone, is one of the crucial observational bases for the solar dynamo to generate a magnetic field by shearing of the pre-existing poloidal magnetic field through differential rotation. The Extended time series of Solar Activity Indices (ESAI) elongated the Greenwich observation record of sunspots by several decades in the past. In this study, ESAI’s yearly mean latitude of sunspots in the northern and southern hemispheres during the years 1854 to 1985 is utilized to statistically test whether hemispherical latitudinal migration of sunspots in a solar cycle is linear or nonlinear. It is found that a quadratic function is statistically significantly better at describing hemispherical latitudinal migration of sunspots in a solar cycle than a linear function. In addition, the latitude migration velocity of sunspots in a solar cycle decreases as the cycle progresses, providing a particular constraint for solar dynamo models. Indeed, the butterfly wing pattern with a faster latitudinal migration rate should present stronger solar activity with a shorter cycle period, and it is located at higher latitudinal position, giving evidence to support the Babcock-Leighton dynamo mechanism.

  8. Bacterial assemblages of the eastern Atlantic Ocean reveal both vertical and latitudinal biogeographic signatures

    Science.gov (United States)

    Friedline, C. J.; Franklin, R. B.; McCallister, S. L.; Rivera, M. C.

    2012-06-01

    Microbial communities are recognized as major drivers of the biogeochemical processes in the oceans. However, the genetic diversity and composition of those communities is poorly understood. The aim of this study is to investigate the composition of bacterial assemblages in three different water layer habitats: surface (2-20 m), deep chlorophyll maximum (DCM; 28-90 m), and deep (100-4600 m) at nine stations along the eastern Atlantic Ocean from 42.8° N to 23.7° S. The sampling of three discrete, predefined habitat types from different depths, Longhurstian provinces, and geographical locations allowed us to investigate whether marine bacterial assemblages show spatial variation and to determine if the observed spatial variation is influenced by current environmental conditions, historical/geographical contingencies, or both. The PCR amplicons of the V6 region of the 16S rRNA from 16 microbial assemblages were pyrosequenced, generating a total of 352 029 sequences; after quality filtering and processing, 257 260 sequences were clustered into 2871 normalized operational taxonomic units (OTU) using a definition of 97% sequence identity. Community ecology statistical analyses demonstrate that the eastern Atlantic Ocean bacterial assemblages are vertically stratified and associated with water layers characterized by unique environmental signals (e.g., temperature, salinity, and nutrients). Genetic compositions of bacterial assemblages from the same water layer are more similar to each other than to assemblages from different water layers. The observed clustering of samples by water layer allows us to conclude that contemporary environments are influencing the observed biogeographic patterns. Moreover, the implementation of a novel Bayesian inference approach that allows a more efficient and explicit use of all the OTU abundance data shows a distance effect suggesting the influence of historical contingencies on the composition of bacterial assemblages. Surface

  9. Bacterial assemblages of the eastern Atlantic Ocean reveal both vertical and latitudinal biogeographic signatures

    Directory of Open Access Journals (Sweden)

    C. J. Friedline

    2012-06-01

    Full Text Available Microbial communities are recognized as major drivers of the biogeochemical processes in the oceans. However, the genetic diversity and composition of those communities is poorly understood. The aim of this study is to investigate the composition of bacterial assemblages in three different water layer habitats: surface (2–20 m, deep chlorophyll maximum (DCM; 28–90 m, and deep (100–4600 m at nine stations along the eastern Atlantic Ocean from 42.8° N to 23.7° S. The sampling of three discrete, predefined habitat types from different depths, Longhurstian provinces, and geographical locations allowed us to investigate whether marine bacterial assemblages show spatial variation and to determine if the observed spatial variation is influenced by current environmental conditions, historical/geographical contingencies, or both. The PCR amplicons of the V6 region of the 16S rRNA from 16 microbial assemblages were pyrosequenced, generating a total of 352 029 sequences; after quality filtering and processing, 257 260 sequences were clustered into 2871 normalized operational taxonomic units (OTU using a definition of 97% sequence identity. Community ecology statistical analyses demonstrate that the eastern Atlantic Ocean bacterial assemblages are vertically stratified and associated with water layers characterized by unique environmental signals (e.g., temperature, salinity, and nutrients. Genetic compositions of bacterial assemblages from the same water layer are more similar to each other than to assemblages from different water layers. The observed clustering of samples by water layer allows us to conclude that contemporary environments are influencing the observed biogeographic patterns. Moreover, the implementation of a novel Bayesian inference approach that allows a more efficient and explicit use of all the OTU abundance data shows a distance effect suggesting the influence of historical contingencies on the composition of bacterial

  10. RNA-Sequencing Analyses Demonstrate the Involvement of Canonical Transient Receptor Potential Channels in Rat Tooth Germ Development

    Directory of Open Access Journals (Sweden)

    Jun Yang

    2017-06-01

    Full Text Available Tooth development depends on multiple molecular interactions between the dental epithelium and mesenchyme, which are derived from ectodermal and ectomesenchymal cells, respectively. We report on a systematic RNA sequencing analysis of transcriptional expression levels from the bud to hard tissue formation stages of rat tooth germ development. We found that GNAO1, ENO1, EFNB1, CALM1, SIAH2, ATP6V0A1, KDELR2, GTPBP1, POLR2C, SORT1, and members of the canonical transient receptor potential (TRPC channel family are involved in tooth germ development. Furthermore, Cell Counting Kit 8 (CCK8 and Transwell migration assays were performed to explore the effects of these differentially expressed genes (DEGs on the proliferation and migration of dental pulp stem cells. Immunostaining revealed that TRPC channels are expressed at varying levels during odontogenesis. The identified genes represent novel candidates that are likely to be vital for rat tooth germ development. Together, the results provide a valuable resource to elucidate the gene regulatory mechanisms underlying mammalian tooth germ development.

  11. Variation in ribosomal and mitochondrial DNA sequences demonstrates the existence of intraspecific groups in Paramecium multimicronucleatum (Ciliophora, Oligohymenophorea).

    Science.gov (United States)

    Tarcz, Sebastian; Potekhin, Alexey; Rautian, Maria; Przyboś, Ewa

    2012-05-01

    This is the first phylogenetic study of the intraspecific variability within Paramecium multimicronucleatum with the application of two-loci analysis (ITS1-5.8S-ITS2-5'LSU rDNA and COI mtDNA) carried out on numerous strains originated from different continents. The species has been shown to have a complex structure of several sibling species within taxonomic species. Our analysis revealed the existence of 10 haplotypes for the rDNA fragment and 15 haplotypes for the COI fragment in the studied material. The mean distance for all of the studied P. multimicronucleatum sequence pairs was p=0.025/0.082 (rDNA/COI). Despite the greater variation of the COI fragment, the COI-derived tree topology is similar to the tree topology constructed on the basis of the rDNA fragment. P. multimicronucleatum strains are divided into three main clades. The tree based on COI fragment analysis presents a greater resolution of the studied P. multimicronucleatum strains. Our results indicate that the strains of P. multimicronucleatum that appear in different clades on the trees could belong to different syngens. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Multiplex Sequence Analysis Demonstrates the Competitive Growth Advantage of the A-to-G Mutants of Clarithromycin-Resistant Helicobacter pylori

    OpenAIRE

    Wang, Ge; Rahman, M. Sayeedur; Humayun, M. Zafri; Taylor, Diane E.

    1999-01-01

    Clarithromycin resistance in Helicobacter pylori is due to point mutation within the 23S rRNA. We examined the growth rates of different types of site-directed mutants and demonstrated quantitatively the competitive growth advantage of A-to-G mutants over other types of mutants by a multiplex sequencing assay. The results provide a rational explanation of why A-to-G mutants are predominantly observed among clarithromycin-resistant clinical isolates.

  13. Multiplex sequence analysis demonstrates the competitive growth advantage of the A-to-G mutants of clarithromycin-resistant Helicobacter pylori.

    Science.gov (United States)

    Wang, G; Rahman, M S; Humayun, M Z; Taylor, D E

    1999-03-01

    Clarithromycin resistance in Helicobacter pylori is due to point mutation within the 23S rRNA. We examined the growth rates of different types of site-directed mutants and demonstrated quantitatively the competitive growth advantage of A-to-G mutants over other types of mutants by a multiplex sequencing assay. The results provide a rational explanation of why A-to-G mutants are predominantly observed among clarithromycin-resistant clinical isolates.

  14. Comparative population genomics of latitudinal variation in Drosophila simulans and Drosophila melanogaster.

    Science.gov (United States)

    Machado, Heather E; Bergland, Alan O; O'Brien, Katherine R; Behrman, Emily L; Schmidt, Paul S; Petrov, Dmitri A

    2016-02-01

    Examples of clinal variation in phenotypes and genotypes across latitudinal transects have served as important models for understanding how spatially varying selection and demographic forces shape variation within species. Here, we examine the selective and demographic contributions to latitudinal variation through the largest comparative genomic study to date of Drosophila simulans and Drosophila melanogaster, with genomic sequence data from 382 individual fruit flies, collected across a spatial transect of 19 degrees latitude and at multiple time points over 2 years. Consistent with phenotypic studies, we find less clinal variation in D. simulans than D. melanogaster, particularly for the autosomes. Moreover, we find that clinally varying loci in D. simulans are less stable over multiple years than comparable clines in D. melanogaster. D. simulans shows a significantly weaker pattern of isolation by distance than D. melanogaster and we find evidence for a stronger contribution of migration to D. simulans population genetic structure. While population bottlenecks and migration can plausibly explain the differences in stability of clinal variation between the two species, we also observe a significant enrichment of shared clinal genes, suggesting that the selective forces associated with climate are acting on the same genes and phenotypes in D. simulans and D. melanogaster. © 2015 John Wiley & Sons Ltd.

  15. Latitudinal variations of TEC over Europe obtained from GPSobservations

    Directory of Open Access Journals (Sweden)

    P. Wielgosz

    2004-01-01

    Full Text Available GPS technique has opened broad possibilities to study the TEC distribution on a regular basis. In this paper, the latitudinal dependence of TEC over Europe for geographic latitudes ranging from 40°N to 75°N is presented. We discuss the day-to-day variations of the latitudinal TEC profiles for a period of 1999 to 2001 for both quiet and disturbed magnetic conditions. More than 4300 TEC profiles were created from the TEC maps with a one-hour interval. GPS data from 65 European permanent stations were used to produce the TEC maps. The comparison of GPS-derived TEC profiles with the IRI model is also discussed.

    Key words. Ionosphere (mid-latitude ionosphere; ionospheric disturbances

  16. Latitudinal variations of TEC over Europe obtained from GPSobservations

    Directory of Open Access Journals (Sweden)

    P. Wielgosz

    2004-01-01

    Full Text Available GPS technique has opened broad possibilities to study the TEC distribution on a regular basis. In this paper, the latitudinal dependence of TEC over Europe for geographic latitudes ranging from 40°N to 75°N is presented. We discuss the day-to-day variations of the latitudinal TEC profiles for a period of 1999 to 2001 for both quiet and disturbed magnetic conditions. More than 4300 TEC profiles were created from the TEC maps with a one-hour interval. GPS data from 65 European permanent stations were used to produce the TEC maps. The comparison of GPS-derived TEC profiles with the IRI model is also discussed. Key words. Ionosphere (mid-latitude ionosphere; ionospheric disturbances

  17. Functional trait space and the latitudinal diversity gradient

    DEFF Research Database (Denmark)

    Lamanna, Christine; Blonder, Benjamin; Violle, Cyrille

    2014-01-01

    The processes causing the latitudinal gradient in species richness remain elusive. Ecological theories for the origin of biodiversity gradients, such as competitive exclusion, neutral dynamics, and environmental filtering, make predictions for how functional diversity should vary at the alpha...... of trait combinations or that niche packing is stronger in the tropical zone. Although there are limitations in the data, our analyses suggest that multiple processes have shaped trait diversity in trees, reflecting no consistent support for any one theory....

  18. Widespread range expansions shape latitudinal variation in insect thermal limits

    Science.gov (United States)

    Lancaster, Lesley T.

    2016-06-01

    Current anthropogenic impacts, including habitat modification and climate change, may contribute to a sixth mass extinction. To mitigate these impacts and slow further losses of biodiversity, we need to understand which species are most at risk and identify the factors contributing to current and future declines. Such information is often obtained through large-scale, comparative and biogeographic analysis of lineages or traits that are potentially sensitive to ongoing anthropogenic change--for instance to predict which regions are most susceptible to climate change-induced biodiversity loss. However, for this approach to be generally successful, the underlying causes of identified geographical trends need to be carefully considered. Here, I augment and reanalyse a global data set of insect thermal tolerances, evaluating the contribution of recent and contemporary range expansions to latitudinal variation in thermal niche breadth. Previous indications that high-latitude ectotherms exhibit broad thermal niches and high warming tolerances held only for species undergoing range expansions or invasions. In contrast, species with stable or declining geographic ranges exhibit latitudinally decreasing absolute thermal tolerances and no latitudinal variation in tolerance breadths. Thus, non-range-expanding species, particularly insular or endemic species, which are often of highest conservation priority, are unlikely to tolerate future climatic warming at high latitudes.

  19. Sequence-Based Discovery Demonstrates That Fixed Light Chain Human Transgenic Rats Produce a Diverse Repertoire of Antigen-Specific Antibodies

    Directory of Open Access Journals (Sweden)

    Katherine E. Harris

    2018-04-01

    Full Text Available We created a novel transgenic rat that expresses human antibodies comprising a diverse repertoire of heavy chains with a single common rearranged kappa light chain (IgKV3-15-JK1. This fixed light chain animal, called OmniFlic, presents a unique system for human therapeutic antibody discovery and a model to study heavy chain repertoire diversity in the context of a constant light chain. The purpose of this study was to analyze heavy chain variable gene usage, clonotype diversity, and to describe the sequence characteristics of antigen-specific monoclonal antibodies (mAbs isolated from immunized OmniFlic animals. Using next-generation sequencing antibody repertoire analysis, we measured heavy chain variable gene usage and the diversity of clonotypes present in the lymph node germinal centers of 75 OmniFlic rats immunized with 9 different protein antigens. Furthermore, we expressed 2,560 unique heavy chain sequences sampled from a diverse set of clonotypes as fixed light chain antibody proteins and measured their binding to antigen by ELISA. Finally, we measured patterns and overall levels of somatic hypermutation in the full B-cell repertoire and in the 2,560 mAbs tested for binding. The results demonstrate that OmniFlic animals produce an abundance of antigen-specific antibodies with heavy chain clonotype diversity that is similar to what has been described with unrestricted light chain use in mammals. In addition, we show that sequence-based discovery is a highly effective and efficient way to identify a large number of diverse monoclonal antibodies to a protein target of interest.

  20. The genetic content of chromosomal inversions across a wide latitudinal gradient.

    Directory of Open Access Journals (Sweden)

    Pedro Simões

    Full Text Available There is increasing evidence regarding the role of chromosomal inversions in relevant biological processes such as local adaptation and speciation. A classic example of the adaptive role of chromosomal polymorphisms is given by the clines of inversion frequencies in Drosophila subobscura, repeatable across continents. Nevertheless, not much is known about the molecular variation associated with these polymorphisms. We characterized the genetic content of ca. 600 individuals from nine European populations following a latitudinal gradient by analysing 19 microsatellite loci from two autosomes (J and U and the sex chromosome (A, taking into account their chromosomal inversions. Our results clearly demonstrate the molecular genetic uniformity within a given chromosomal inversion across a large latitudinal gradient, particularly from Groningen (Netherlands in the north to Málaga (Spain in the south, experiencing highly diverse environmental conditions. This low genetic differentiation within the same gene arrangement across the nine European populations is consistent with the local adaptation hypothesis for th evolutionof chromosomal polymorphisms. We also show the effective role of chromosomal inversions in maintaining different genetic pools within these inverted genomic regions even in the presence of high gene flow. Inversions represent thus an important barrier to gene flux and can help maintain specific allelic combinations with positive effects on fitness. Consistent patterns of microsatellite allele-inversion linkage disequilibrium particularly in loci within inversions were also observed. Finally, we identified areas within inversions presenting clinal variation that might be under selection.

  1. Orbital forcing and role of the latitudinal insolation/temperature gradient

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Basil A.S. [University of Newcastle, School of Geography, Politics and Sociology, Newcastle upon Tyne (United Kingdom); ARVE Group, ISTE, EPFL, Lausanne (Switzerland); Brewer, Simon [CEREGE, Europole de l' Arbois, Aix-en-Provence (France)

    2009-02-15

    Orbital forcing of the climate system is clearly shown in the Earths record of glacial-interglacial cycles, but the mechanism underlying this forcing is poorly understood. Traditional Milankovitch theory suggests that these cycles are driven by changes in high latitude summer insolation, yet this forcing is dominated by precession, and cannot account for the importance of obliquity in the Ice Age record. Here, we investigate an alternative forcing based on the latitudinal insolation gradient (LIG), which is dominated by both obliquity (in summer) and precession (in winter). The insolation gradient acts on the climate system through differential solar heating, which creates the Earths latitudinal temperature gradient (LTG) that drives the atmospheric and ocean circulation. A new pollen-based reconstruction of the LTG during the Holocene is used to demonstrate that the LTG may be much more sensitive to changes in the LIG than previously thought. From this, it is shown how LIG forcing of the LTG may help explain the propagation of orbital signatures throughout the climate system, including the Monsoon, Arctic Oscillation and ocean circulation. These relationships are validated over the last (Eemian) Interglacial, which occurred under a different orbital configuration to the Holocene. We conclude that LIG forcing of the LTG explains many criticisms of classic Milankovitch theory, while being poorly represented in climate models. (orig.)

  2. Latitudinal variation in cold hardiness in introduced Tamarix and native Populus

    Science.gov (United States)

    Friedman, Jonathan M.; Roelle, James E.; Gaskin, John F.; Pepper, Alan E.; Manhart, James R.

    2008-01-01

    To investigate the evolution of clinal variation in an invasive plant, we compared cold hardiness in the introduced saltcedar (Tamarix ramosissima, Tamarix chinensis, and hybrids) and the native plains cottonwood (Populus deltoidessubsp. monilifera). In a shadehouse in Colorado (41°N), we grew plants collected along a latitudinal gradient in the central United States (29–48°N). On 17 occasions between September 2005 and June 2006, we determined killing temperatures using freeze-induced electrolyte leakage and direct observation. In midwinter, cottonwood survived cooling to −70°C, while saltcedar was killed at −33 to −47°C. Frost sensitivity, therefore, may limit northward expansion of saltcedar in North America. Both species demonstrated inherited latitudinal variation in cold hardiness. For example, from September through January killing temperatures for saltcedar from 29.18°N were 5–21°C higher than those for saltcedar from 47.60°N, and on September 26 and October 11, killing temperatures for cottonwood from 33.06°N were >43°C higher than those for cottonwood from 47.60°N. Analysis of nine microsatellite loci showed that southern saltcedars are more closely related to T. chinensis while northern plants are more closely related to T. ramosissima. Hybridization may have introduced the genetic variability necessary for rapid evolution of the cline in saltcedar cold hardiness.

  3. Tree growth and its climate signal along latitudinal and altitudinal gradients: comparison of tree rings between Finland and the Tibetan Plateau

    Directory of Open Access Journals (Sweden)

    L. Lyu

    2017-06-01

    Full Text Available Latitudinal and altitudinal gradients can be utilized to forecast the impact of climate change on forests. To improve the understanding of how these gradients impact forest dynamics, we tested two hypotheses: (1 the change of the tree growth–climate relationship is similar along both latitudinal and altitudinal gradients, and (2 the time periods during which climate affects growth the most occur later towards higher latitudes and altitudes. To address this, we utilized tree-ring data from a latitudinal gradient in Finland and from two altitudinal gradients on the Tibetan Plateau. We analysed the latitudinal and altitudinal growth patterns in tree rings and investigated the growth–climate relationship of trees by correlating ring-width index chronologies with climate variables, calculating with flexible time windows, and using daily-resolution climate data. High latitude and altitude plots showed higher correlations between tree-ring chronologies and growing season temperature. However, the effects of winter temperature showed contrasting patterns for the gradients. The timing of the highest correlation with temperatures during the growing season at southern sites was approximately 1 month ahead of that at northern sites in the latitudinal gradient. In one out of two altitudinal gradients, the timing for the strongest negative correlation with temperature at low-altitude sites was ahead of treeline sites during the growing season, possibly due to differences in moisture limitation. Mean values and the standard deviation of tree-ring width increased with increasing mean July temperatures on both types of gradients. Our results showed similarities of tree growth responses to increasing seasonal temperature between latitudinal and altitudinal gradients. However, differences in climate–growth relationships were also found between gradients due to differences in other factors such as moisture conditions. Changes in the timing of the most

  4. Latitudinal gradients in ecosystem engineering by oysters vary across habitats.

    Science.gov (United States)

    McAfee, Dominic; Cole, Victoria J; Bishop, Melanie J

    2016-04-01

    Ecological theory predicts that positive interactions among organisms will increase across gradients of increasing abiotic stress or consumer pressure. This theory has been supported by empirical studies examining the magnitude of ecosystem engineering across environmental gradients and between habitat settings at local scale. Predictions that habitat setting, by modifying both biotic and abiotic factors, will determine large-scale gradients in ecosystem engineering have not been tested, however. A combination of manipulative experiments and field surveys assessed whether along the east Australian coastline: (1) facilitation of invertebrates by the oyster Saccostrea glomerata increased across a latitudinal gradient in temperature; and (2) the magnitude of this effect varied between intertidal rocky shores and mangrove forests. It was expected that on rocky shores, where oysters are the primary ecosystem engineer, they would play a greater role in ameliorating latitudinal gradients in temperature than in mangroves, where they are a secondary ecosystem engineer living under the mangrove canopy. On rocky shores, the enhancement of invertebrate abundance in oysters as compared to bare microhabitat decreased with latitude, as the maximum temperatures experienced by intertidal organisms diminished. By contrast, in mangrove forests, where the mangrove canopy resulted in maximum temperatures that were cooler and of greater humidity than on rocky shores, we found no evidence of latitudinal gradients of oyster effects on invertebrate abundance. Contrary to predictions, the magnitude by which oysters enhanced biodiversity was in many instances similar between mangroves and rocky shores. Whether habitat-context modifies patterns of spatial variation in the effects of ecosystem engineers on community structure will depend, in part, on the extent to which the environmental amelioration provided by an ecosystem engineer replicates that of other co-occurring ecosystem engineers.

  5. A latitudinal study of oxygen isotopes within horsehair

    Science.gov (United States)

    Thompson, E.; Bronk Ramsey, C.; McConnell, J. R.

    2016-12-01

    This study aims to explore the hypothesis that 'if oxygen isotope ratios deplete with decreasing temperature then a study of oxygen isotope ratios within horsehair from Oxfordshire to Iceland will show a latitudinal depletion gradient'. By looking at oxygen isotope values at different geographical positions, we can track the relationship with latitude and with different regional climate features. This will provide a firmer understanding of how to compare climate records from different locations. Additionally, a comparison of the horse breeds from this study to those analysed within previous studies will create an even better understanding of the intra-species variation within the δ18O values of horsehair. A total of 24 horses were sampled on the 7th March from Thordale Stud in Shetland, the Icelandic Food And Veterinary Authority in Iceland, the Exmoor Pony Centre in Exmoor and the Pigeon House Equestrian Centre in Oxfordshire. By starting the sampling process from the most recent growth at the follicle, the sampling date becomes a chronological marker, temporally fixing the first sample within a sequential set of data points extending for one year or longer, depending on the length of each individual hair. The samples were analysed for oxygen isotope values using an IRMS coupled within a Sercon HTEA. Preliminary results show a latitudinal gradient is evident on comparison between the locations, consistent with the findings of Darling and Talbot's study of fresh water isotopes in the British Isles (2003). These results support the hypothesis, showing that a study of oxygen isotope ratios within horse hair from Oxfordshire to Iceland showing a latitudinal depletion gradient, consistent with a depletion of oxygen isotope ratios due to decreasing temperatures. Darling, W. and Talbot, J. (2003). The O and H stable isotope composition of freshwaters in the British Isles. 1. Rainfall. Hydrol. Earth System Science, 7(2), pp.163-181.

  6. Latitudinal distribution of earthquakes in the Andes and its peculiarity

    Directory of Open Access Journals (Sweden)

    B. W. Levin

    2009-12-01

    Full Text Available In the last decade, there has been growing interest in problems related to searching global spatiotemporal regularities in the distribution of seismic events on the Earth. The worldwide catalogs ISC were used for search of spatial and temporal distribution of earthquakes (EQ in the Pacific part of South America. We extracted all EQ from 1964 to 2004 with Mb>=4.0. The total number of events under study is near 30 000. The entire set of events was divided into six magnitude ranges (MR: 4.0<=Mb<4.5; 4.5<=Mb<5.0; 5.0<=Mb<5.5; 5.5<=Mb<6.0; 6.0<=Mb<6.5; and 6.5<=Mb. Further analysis was performed separately for each MR. The latitude distributions of the EQ number for all MR were studied. The whole region was divided in several latitudinal intervals (size of each interval was either 5° or 10°. The number of events in each latitudinal interval was normalized two times. After normalization we obtained the relative seismic event number generated per one kilometer of plate boundary. The maximum of seismic activity in the Pacific part of the South America is situated in latitude interval 20°–30° S. The comparative analysis was executed for the latitude distributions of the EQ number and the EQ energy released. Then the distributions of EQ hypocenter location in latitude and in depth were studied. The EQ sources for the high latitudes (up to 35° S are located on the depth (H between 20–80 km. It was shown, that full interval of depth in each latitudinal belt generally divides into three parts (clusters with close-cut separation boundaries (K1 – with 0K2 – with 120K3 – with H>=500 km.

  7. Radar measurements of the latitudinal variation of auroral ionization

    International Nuclear Information System (INIS)

    Vondrak, R.R.; Baron, M.J.

    1976-01-01

    The Chatanika, Alaska, incoherent scatter radar has been used to measure the spatial variation of auroral ionization. A two-dimensional (altitude, latitude) cross-sectional map of electron densities in the ionosphere is produced by scanning in the geomagnetic meridian plane. The altitutde variation of ionization is used to infer the differential energy distribution of the incident auroral electrons. The latitudinal variation of this energy distribution and the total energy input are obtained by use of the meridian-scanning technique. Examples are shown of observations made during an active aurora

  8. Latitudinal and longitudinal dispersion of energetic auroral protons

    Directory of Open Access Journals (Sweden)

    D. A. Lorentzen

    2000-01-01

    Full Text Available Using a collision by collision model from Lorentzen et al., the latitudinal and longitudinal dispersion of single auroral protons are calculated. The proton energies varies from 1 to 50 keV, and are released into the atmosphere at 700 km altitude. The dipole magnetic field has a dip-angle of 8 degrees. Results show that the main dispersion region is at high altitudes (300-350 km and occurs during the first few charge exchange collisions. As the proton travels further down the atmosphere the mean free path becomes smaller, and as a result the spreading effect will not be as pronounced. This means that the first few charge exchange collisions fully determines the width of both the latitudinal and longitudinal dispersion. The volume emission rate was calculated for energies between 1 and 50 keV, and it was found that dayside auroral hydrogen emissions rates were approximately 10 times weaker than nightside emission rates. Simulations were also performed to obtain the dependence of the particle dispersion as a function of initial pitch-angle. It was found that the dispersion varies greatly with initial pitch-angle, and the results are summarized in two tables; a main and an extreme dispersion region.Key words. Ionosphere (auroral ionosphere; · particle precipitation · Space plasma physics · (transport processes

  9. Latitudinal variation of the polar cusp during a geomagnetic storm

    International Nuclear Information System (INIS)

    Meng, C.

    1982-01-01

    Large amplitude latitudinal variation of the polar cusp position was observed during the intense geomagnetic storm of 15--16 February 1980. The observation of the polar cusp, identified as the region of intense but extremely soft electron precipitation, was made by two nearly noon-midnight orbit DMSP satellites over both northern and southern hemispheres. The latitudinal shift of the polar cusp is observed to be related to the intensity variation of the ring current indicated by the hourly Dst values. The polar cusp region moved from its normal location at approx.76 0 gm lat down to approx.62 0 gm lat at the peak of this storm. This movement took about 5 hours and was detected over both hemispheres. A drastic variation in the width of the cusp region was also observed; it is very narrow (approx.1 0 ) during the equatorial shift and expands to > or approx. =5 0 during the poleward recovery. Variation of the polar cusp latitude with that of the Dst index was also seen during the period before the intense storm

  10. Latitudinal and longitudinal dispersion of energetic auroral protons

    Directory of Open Access Journals (Sweden)

    D. A. Lorentzen

    Full Text Available Using a collision by collision model from Lorentzen et al., the latitudinal and longitudinal dispersion of single auroral protons are calculated. The proton energies varies from 1 to 50 keV, and are released into the atmosphere at 700 km altitude. The dipole magnetic field has a dip-angle of 8 degrees. Results show that the main dispersion region is at high altitudes (300-350 km and occurs during the first few charge exchange collisions. As the proton travels further down the atmosphere the mean free path becomes smaller, and as a result the spreading effect will not be as pronounced. This means that the first few charge exchange collisions fully determines the width of both the latitudinal and longitudinal dispersion. The volume emission rate was calculated for energies between 1 and 50 keV, and it was found that dayside auroral hydrogen emissions rates were approximately 10 times weaker than nightside emission rates. Simulations were also performed to obtain the dependence of the particle dispersion as a function of initial pitch-angle. It was found that the dispersion varies greatly with initial pitch-angle, and the results are summarized in two tables; a main and an extreme dispersion region.

    Key words. Ionosphere (auroral ionosphere; · particle precipitation · Space plasma physics · (transport processes

  11. Search for possible latitudinal ecotypes in Dumontia contorta (Rhodophyta)

    Science.gov (United States)

    Rietema, H.; van den Hoek, C.

    1984-09-01

    Effects of daylength and temperature on the formation of erect fronds (macrothalli) from crusts (microthalli) of Dumontia contorta (S. G. Gmel.) Rupr. from three localities in Nova Scotia and one locality in Southern Iceland were investigated and compared to such effects shown by strains from three different East Atlantic localities (Isle of Man; Zeeland, S. W. Netherlands; and Roscoff, Brittany, France). Although these strains showed small differences in their temperature-daylength responses, these could not be interpreted as latitudinal adaptations, and consequently no latitudinal ecotypes could be found for Dumontia contorta in the N. Atlantic Ocean. Upright fronds are formed at a broad temperature range of about 4°-18°C and at daylengths ≤ 13 h. Only in the southernmost part of its distribution area can high autumnal temperatures be expected to block the reappearance of upright fronds after passage of the critical daylength in September. In the larger part of the distribution area even summer temperatures are not high enough to block formation of uprights and here apparently only short daylengths initiate the reappearance of young upright fronds in autumn. The consequences of these aspects of the life history regulation for the geographic distribution are discussed.

  12. Latitudinal Dependence of the Radial IMF Component: Coronal Imprint

    Science.gov (United States)

    Suess, S. T.; Smith, E. J.

    1996-01-01

    Measurements by Ulysses have confirmed that there is no significant gradient with respect to heliomagnetic latitude in the radial component, B(sub r,) of the interplanetary magnetic field. In the corona, the plasma, beta is much less than 1, except directly above streamers, so longitudinal and latitudinal gradients in field strength will relax due to the transverse magnetic pressure gradient force as the solar wind carries magnetic flux away from the Sun. This happens quickly enough so that the field is essentially uniform by 5 - 10 solar radius, apparently remaining so as it is carried to beyond 1 AU. Here, we illustrate the coronal relaxation with a qualitative physical argument and by reference to a detailed Magneto HydroDynamics (MHD) simulation.

  13. Latitudinal oscillations of plasma within the Io torus

    Science.gov (United States)

    Cummings, W. D.; Dessler, A. J.; Hill, T. W.

    1980-01-01

    The equilibrium latitude and the period of oscillations about this equilibrium latitude are calculated for a plasma in a centrifugally dominated tilted dipole magnetic field representing Jupiter's inner magnetosphere. It is found that for a hot plasma the equilibrium latitude in the magnetic equator, for a cold plasma it is the centrifugal equator, and for a warm plasma it is somewhere in between. An illustrative model is adopted in which atoms are sputtered from the Jupiter-facing hemisphere of Io and escape Io's gravity to be subsequently ionized some distance from Io. Finally, it is shown that ionization generally does not occur at the equilibrium altitude, and that the resulting latitudinal oscillations provide an explanation for the irregularities in electron concentration within the torus, as reported by the radioastronomy experiment aboard Voyager I.

  14. Origination and immigration drive latitudinal gradients in marine functional diversity.

    Directory of Open Access Journals (Sweden)

    Sarah K Berke

    Full Text Available Global patterns in the functional attributes of organisms are critical to understanding biodiversity trends and predicting biotic responses to environmental change. In the first global marine analysis, we find a strong decrease in functional richness, but a strong increase in functional evenness, with increasing latitude using intertidal-to-outer-shelf bivalves as a model system (N = 5571 species. These patterns appear to be driven by the interplay between variation in origination rates among functional groups, and latitudinal patterns in origination and range expansion, as documented by the rich fossil record of the group. The data suggest that (i accumulation of taxa in spatial bins and functional categories has not impeded continued diversification in the tropics, and (ii extinctions will influence ecosystem function differentially across latitudes.

  15. Latitudinal and altitudinal controls of Titan's dune field morphometry

    Science.gov (United States)

    Le Gall, A.; Hayes, A. G.; Ewing, R.; Janssen, M. A.; Radebaugh, J.; Savage, C.; Encrenaz, P.; the Cassini Radar Team

    2012-01-01

    Dune fields dominate ˜13% of Titan's surface and represent an important sink of carbon in the methane cycle. Herein, we discuss correlations in dune morphometry with altitude and latitude. These correlations, which have important implications in terms of geological processes and climate on Titan, are investigated through the microwave electromagnetic signatures of dune fields using Cassini radar and radiometry observations. The backscatter and emissivity from Titan's dune terrains are primarily controlled by the amount of interdune area within the radar footprint and are also expected to vary with the degree of the interdunal sand cover. Using SAR-derived topography, we find that Titan's main dune fields (Shangri-La, Fensal, Belet and Aztlan) tend to occupy the lowest elevation areas in Equatorial regions occurring at mean elevations between ˜-400 and ˜0 m (relative to the geoid). In elevated dune terrains, we show a definite trend towards a smaller dune to interdune ratio and possibly a thinner sand cover in the interdune areas. A similar correlation is observed with latitude, suggesting that the quantity of windblown sand in the dune fields tends to decrease as one moves farther north. The altitudinal trend among Titan's sand seas is consistent with the idea that sediment source zones most probably occur in lowlands, which would reduce the sand supply toward elevated regions. The latitudinal preference could result from a gradual increase in dampness with latitude due to the asymmetric seasonal forcing associated with Titan's current orbital configuration unless it is indicative of a latitudinal preference in the sand source distribution or wind transport capacity.

  16. Trophic diversity, size and biomass spectrum of Bay of Bengal nematodes: A study case on depth and latitudinal patterns

    Science.gov (United States)

    Ansari, Kapuli Gani Mohamed Thameemul; Lyla, Somasundharanair; Khan, Syed Ajmal; Bhadury, Punyasloke

    2017-09-01

    Depth and latitudinal patterns of nematode functional attributes were investigated from 35 stations of Bay of Bengal (BoB) continental shelf. We aim to address whether depth and latitudinal variations can modify nematode community structure and their functional attributes (trophic diversity, size and biomass spectra). Global trend of depth and latitudinal related variations have also been noticed from BoB shelf in terms of nematode abundance and species richness, albeit heterogeneity patterns were encountered in functional attributes. Index of trophic diversity values revealed higher trophic diversity across the BoB shelf and suggested variety of food resource availability. However, downstream analysis of trophic status showed depth and latitude specific patterns but not reflected in terms of size and biomass spectrum. The peaks at different positions clearly visualized heterogeneity in distribution patterns for both size and biomass spectrum and also there was evidence of availability of diversified food resources. Nematode biomass spectra (NBS) constructed for nematode communities showed shift in peak biomass values towards lower to moderate size classes particularly in shallower depth but did not get reflected in latitudes. However, Chennai and Parangipettai transects demonstrated shift in peak biomass values towards higher biomass classes explaining the representation of higher nematode abundance. Our findings concluded that depth and latitudes are physical variables; they may not directly affect nematode community structure and functional attributes but they might influence the other factors such as food availability, sediment deposition and settlement rate. Our observations suggest that the local factors (seasonal character) of phytodetrital food flux can be very important for shaping the nematode community structure and success of nematode functional heterogeneity patterns across the Bay of Bengal shelf.

  17. Latitudinal environmental gradients and diel variability influence abundance and community structure of Chaetognatha in Red Sea coral reefs

    KAUST Repository

    Al-aidaroos, Ali M.

    2016-08-15

    The Red Sea has been recognized as a unique region to study the effects of ecohydrographic gradients at a basin-wide scale. Its gradient of temperature and salinity relates to the Indian Ocean monsoon and associated wind-driven transport of fertile and plankton-rich water in winter from the Gulf of Aden into the Red Sea. Subsequent evaporation and thermohaline circulation increase the salinity and decrease water temperatures toward the North. Compared with other ocean systems, however, relatively little is known about the zooplankton biodiversity of the Red Sea and how this relates to Red Sea latitudinal gradients. Among the most abundant zooplankton taxa are Chaetognatha, which play an important role as secondary consumers in most marine food webs. Since Chaetognatha are sensitive to changes in temperature and salinity, we surmised latitudinal changes in their biodiversity, community structure and diel variability along the coast of Saudi Arabia. Samples were collected at nine coral reefs spanning approximately 1500km, from the Gulf of Aqaba in the northern Red Sea to the Farasan Archipelago in the southern Red Sea. Thirteen Chaetognatha species belonging to two families (Sagittidae and Krohnittidae) were identified. Latitudinal environmental changes and availability of prey (i.e. Copepoda, Crustacea) altered Chaetognatha density and distribution. The cosmopolitan epiplanktonic Flaccisagitta enflata (38.1%) dominated the Chaetognatha community, and its abundance gradually decreased from South to North. Notable were two mesopelagic species (Decipisagitta decipiens and Caecosagitta macrocephala) in the near-reef surface mixed layers at some sites. This was related to wind-induced upwelling of deep water into the coral reefs providing evidence of trophic oceanic subsidies. Most Sagittidae occurred in higher abundances at night, whereas Krohnittidae were more present during the day. Chaetognatha with developing (stage II) or mature ovaries (stage III) were more active

  18. Contrasting growth forecasts across the geographical range of Scots pine due to altitudinal and latitudinal differences in climatic sensitivity.

    Science.gov (United States)

    Matías, Luis; Linares, Juan C; Sánchez-Miranda, Ángela; Jump, Alistair S

    2017-10-01

    Ongoing changes in global climate are altering ecological conditions for many species. The consequences of such changes are typically most evident at the edge of a species' geographical distribution, where differences in growth or population dynamics may result in range expansions or contractions. Understanding population responses to different climatic drivers along wide latitudinal and altitudinal gradients is necessary in order to gain a better understanding of plant responses to ongoing increases in global temperature and drought severity. We selected Scots pine (Pinus sylvestris L.) as a model species to explore growth responses to climatic variability (seasonal temperature and precipitation) over the last century through dendrochronological methods. We developed linear models based on age, climate and previous growth to forecast growth trends up to year 2100 using climatic predictions. Populations were located at the treeline across a latitudinal gradient covering the northern, central and southernmost populations and across an altitudinal gradient at the southern edge of the distribution (treeline, medium and lower elevations). Radial growth was maximal at medium altitude and treeline of the southernmost populations. Temperature was the main factor controlling growth variability along the gradients, although the timing and strength of climatic variables affecting growth shifted with latitude and altitude. Predictive models forecast a general increase in Scots pine growth at treeline across the latitudinal distribution, with southern populations increasing growth up to year 2050, when it stabilizes. The highest responsiveness appeared at central latitude, and moderate growth increase is projected at the northern limit. Contrastingly, the model forecasted growth declines at lowland-southern populations, suggesting an upslope range displacement over the coming decades. Our results give insight into the geographical responses of tree species to climate change

  19. Latitudinal Dependence of the Radial IMF Component - Interplanetary Imprint

    Science.gov (United States)

    Suess, S. T.; Smith, E. J.; Phillips, J.; Goldstein, B. E.; Nerney, S.

    1996-01-01

    Ulysses measurements have confirmed that there is no significant gradient with respect to heliomagnetic latitude in the radial component, B(sub r,), of the interplanetary magnetic field. There are two processes responsible for this observation. In the corona, the plasma beta is much less than 1, except directly above streamers, so both longitudinal and latitudinal (meridional) gradients in field strength will relax, due to the transverse magnetic pressure gradient force, as the solar wind carries magnetic flux away from the Sun. This happens so quickly that the field is essentially uniform by 5 solar radius. Beyond 10 solar radius, beta is greater than 1 and it is possible for a meridional thermal pressure gradient to redistribute magnetic flux - an effect apparently absent in Ulysses and earlier ICE and Interplanetary Magnetic Physics (IMP) data. We discuss this second effect here, showing that its absence is mainly due to the perpendicular part of the anisotropic thermal pressure gradient in the interplanetary medium being too small to drive significant meridional transport between the Sun and approx. 4 AU. This is done using a linear analytic estimate of meridional transport. The first effect was discussed in an earlier paper.

  20. Physiological constraints and latitudinal breeding season in the Canidae.

    Science.gov (United States)

    Valdespino, Carolina

    2007-01-01

    Physiological strategies that maximize reproductive success may be phylogenetically constrained or might have a plastic response to different environmental conditions. Among mammals, Canidae lend themselves to the study of these two influences on reproductive physiology because all the species studied to date have been characterized as monestrous (i.e., a single ovulatory event per breeding season), suggesting a phylogenetic effect. Greater flexibility could be associated with environments that are less seasonal, such as the tropics; however, little is known for many of the species from this region. To compensate for this lack of data, two regressions were done on the length of the reproductive season relative to the latitudinal distribution of a species: one with raw data and another with phylogenetically independent contrasts. There was a significant negative relationship, independent of phylogeny, with canids that have longer breeding seasons occurring at lower latitudes. In contrast, the pervasiveness of monestrus within Canidae appears to be phylogenetically constrained by their pairing/packing life and is most likely associated with monogamy. The persistence of the monestrous condition is supported by a captive study where a tropical canid, the fennec fox, Vulpes zerda, never exhibited polyestrous cycles despite a constant photoperiod (12L : 12D).

  1. Latitudinal beaming of Jupiter's low frequency radio emissions

    International Nuclear Information System (INIS)

    Alexander, J.K.; Desch, M.D.; Kaiser, M.L.; Thieman, J.R.

    1979-01-01

    By comparing Rae 1 and Imp 6 satelite measurements of Jupiter's radio emissions near 1 MHz with recent Voyager 1 and 2 observations in the same frequency range it is now possible to study the properties of the low frequency radiation pattern over a 10 0 range of latitudes with respect to the Jovian rotation equator. These observations, which cover a wider latitudinal range than is possible from the earth, are consistent with many aspect of earlier ground-based measurements that have been used to infer a sharp beaming pattern for the decameter wavelength emissions. We find marked, systematic changes in the statistical occurrence probability distributions with system III central meridian longitude as the Jovigraphic latitude of the observer changes over this range. Moreover, simultaneous observations by the two Voyager spacecraft, which are separated by up to 3 0 in Jovigraphic latitude, suggest that the instantaneous beam width may be no more than a few degrees at times. The new hectometer wave results can be interpreted in terms of a narrow, curved sheet at a fixed magnetic latitude into which the emission is beamed to escape the planet

  2. Latitudinal variation of air sea fluxes in the western Indian Ocean during austral summer and fall

    Digital Repository Service at National Institute of Oceanography (India)

    RameshKumar, M.R.; Rao, L.V.G.

    Daily and zonal (latitudinal belt) averages of heat and momentum fluxes were computed using bulk aerodynamic formulae, from the meteorological parameters measured onboard 'M.S. Thuleland' during the sixth Indian scientific expedition to Antarctica...

  3. Contrasting latitudinal patterns of life-history divergence in two genera of new world thrushes (Turdinae)

    Science.gov (United States)

    Boyce, Andy J.; Martin, Thomas E.

    2017-01-01

    Several long-standing hypotheses have been proposed to explain latitudinal patterns of life-history strategies. Here, we test predictions of four such hypotheses (seasonality, food limitation, nest predation and adult survival probability) by examining life-history traits and age-specific mortality rates of several species of thrushes (Turdinae) based on field studies at temperate and tropical sites and data gathered from the literature. Thrushes in the genus Catharus showed the typical pattern of slower life-history strategies in the tropics while co-occuring Turdus thrushes differed much less across latitudes. Seasonality is a broadly accepted hypothesis for latitudinal patterns, but the lack of concordance in latitudinal patterns between co-existing genera that experience the same seasonal patterns suggests seasonality cannot fully explain latitudinal trait variation in thrushes. Nest-predation also could not explain patterns based on our field data and literature data for these two genera. Total feeding rates were similar, and per-nestling feeding rates were higher at tropical latitudes in both genera, suggesting food limitation does not explain trait differences in thrushes. Latitudinal patterns of life histories in these two genera were closely associated with adult survival probability. Thus, our data suggest that environmental influences on adult survival probability may play a particularly strong role in shaping latitudinal patterns of life-history traits.

  4. 16S rRNA Amplicon Sequencing Demonstrates that Indoor-Reared Bumblebees (Bombus terrestris Harbor a Core Subset of Bacteria Normally Associated with the Wild Host.

    Directory of Open Access Journals (Sweden)

    Ivan Meeus

    Full Text Available A MiSeq multiplexed 16S rRNA amplicon sequencing of the gut microbiota of wild and indoor-reared Bombus terrestris (bumblebees confirmed the presence of a core set of bacteria, which consisted of Neisseriaceae (Snodgrassella, Orbaceae (Gilliamella, Lactobacillaceae (Lactobacillus, and Bifidobacteriaceae (Bifidobacterium. In wild B. terrestris we detected several non-core bacteria having a more variable prevalence. Although Enterobacteriaceae are unreported by non next-generation sequencing studies, it can become a dominant gut resident. Furthermore the presence of some non-core lactobacilli were associated with the relative abundance of bifidobacteria. This association was not observed in indoor-reared bumblebees lacking the non-core bacteria, but having a more standardized microbiota compared to their wild counterparts. The impact of the bottleneck microbiota of indoor-reared bumblebees when they are used in the field for pollination purpose is discussed.

  5. Quasi-periodic latitudinal shift of Saturn's main auroral emission

    Science.gov (United States)

    Roussos, E.; Palmaerts, B.; Grodent, D. C.; Radioti, K.; Krupp, N.; Yao, Z.

    2017-12-01

    The main component of the ultraviolet auroral emissions at Saturn consists in a ring of emission around each pole of the planet. This main ring of emission has been revealed to oscillate by a few degrees in the prenoon-premidnight direction with a period of 10.8h. This auroral oscillation is thought to be induced by a rotating external magnetospheric current system associated with the planetary period oscillations. Here we report, by means of auroral imaging sequences obtained with the Ultraviolet Imaging Spectrograph (UVIS) on board the Cassini spacecraft, the first direct observation of an additional motion of the main emission superimposed to this oscillation. The whole main emission ring exhibits step-like displacements in latitude mainly towards dayside, decoupled from the 10.8h oscillation. These latitude shifts recur around every hour, which is a typical short periodicity at Saturn previously identified in the aurora intensity, in the charged particle fluxes and in the magnetic field. This unique observation directly demonstrates what has been inferred from past in-situ and remote measurements: the 1-hour periodicities reveal a global and fundamental magnetospheric oscillation mode that acts independently of the local magnetospheric conditions. However, the magnetospheric mechanism responsible for these 1-hour auroral shifts is still unknown. It is possible that Alfvén waves inducing hourly magnetic fluctuations might also modify the place where the field-aligned electrons precipitate in the ionosphere and produce the main emission.

  6. Peatland Organic Matter Chemistry Trends Over a Global Latitudinal Gradient

    Science.gov (United States)

    Verbeke, B. A.; Hodgkins, S. B.; Carson, M. A.; Lamit, L. J.; Lilleskov, E.; Chanton, J.

    2017-12-01

    Peatlands contain a significant amount of the global soil carbon, and the climate feedback of carbon cycling within these peatland systems is still relatively unknown. Organic matter composition of peatlands plays a major role in determining carbon storage, and while high latitude peatlands seem to be the most sensitive to climate change, a global picture of peat organic matter chemistry is required to improve predictions and models of greenhouse gas emissions fueled by peatland decomposition. The objective of this research is to test the hypothesis that carbohydrate content of peatlands near the equator will be lower than high latitude peatlands, while aromatic content will be higher. As a part of the Global Peatland Microbiome Project (GPMP), around 2000 samples of peat from 10 to 70 cm across a latitudinal gradient of 79 N to 53 S were measured with Fourier transform infrared spectroscopy (FTIR) to examine the organic matter functional groups of peat. Carbohydrate and aromatic content, as determined by FTIR, are useful proxies of decomposition potential and recalcitrance, respectively. We found a highly significant relationship between carbohydrate and aromatic content, latitude, and depth. Carbohydrate content of high latitude sites were significantly greater than at sites near the equator, in contrast to aromatic content which showed the opposite trend. It is also clear that carbohydrate content decreases with depth while aromatic content increases with depth. Higher carbohydrate content at higher latitudes indicates a greater potential for lability and resultant mineralization to form the greenhouse gases, carbon dioxide and methane, whereas the composition of low latitude peatlands is consistent with their apparent stability. We speculate that the combination of low carbohydrates and high aromatics at warmer locations near the equator could foreshadow the organic matter composition of high latitude peat transitioning to a more recalcitrant form with a

  7. Latitudinal variation of phytoplankton communities in the western Arctic Ocean

    Science.gov (United States)

    Min Joo, Hyoung; Lee, Sang H.; Won Jung, Seung; Dahms, Hans-Uwe; Hwan Lee, Jin

    2012-12-01

    Recent studies have shown that photosynthetic eukaryotes are an active and often dominant component of Arctic phytoplankton assemblages. In order to explore this notion at a large scale, samples were collected to investigate the community structure and biovolume of phytoplankton along a transect in the western Arctic Ocean. The transect included 37 stations at the surface and subsurface chlorophyll a maximum (SCM) depths in the Bering Sea, Chukchi Sea, and Canadian Basin from July 19 to September 5, 2008. Phytoplankton (>2 μm) were identified and counted. A cluster analysis of abundance and biovolume data revealed different assemblages over the shelf, slope, and basin regions. Phytoplankton communities were composed of 71 taxa representing Dinophyceae, Cryptophyceae, Bacillariophyceae, Chrysophyceae, Dictyochophyceae, Prasinophyceae, and Prymnesiophyceae. The most abundant species were of pico- to nano-size at the surface and SCM depths at most stations. Nano- and pico-sized phytoplankton appeared to be dominant in the Bering Sea, whereas diatoms and nano-sized plankton provided the majority of taxon diversity in the Bering Strait and in the Chukchi Sea. From the western Bering Sea to the Bering Strait, the abundance, biovolume, and species diversity of phytoplankton provided a marked latitudinal gradient towards the central Arctic. Although pico- and nano-sized phytoplankton contributed most to cell abundance, their chlorophyll a contents and biovolumes were less than those of the larger micro-sized taxa. Micro-sized phytoplankton contributed most to the biovolume in the largely ice-free waters of the western Arctic Ocean during summer 2008.

  8. Some problems concerning the regularities in the development of the latitudinal distribution of solar magnetic fields

    International Nuclear Information System (INIS)

    Bumba, V.; Hejna, L.

    1988-01-01

    From the comparison of several modes of time development of the latitudinal distribution of solar magnetic fields, obtained by different authors using different basic observational material and different methods, the following results were obtained: At high solar latitudes (|φ|> or ∼ 40deg) all distributions agree irrespective of the method of construction. In zones of activity around the solar equator, there is a qualitatively good but quantitatively poor agreement of the integrated, directly observed fields (from Mt. Wilson Observatory) and of the highly integrated fields derived from Hα synoptic charts. The mode of field distribution at high latitudes, more uniform and unipolar, is probably different from the field distribution at low latitudes where the more concentrated leading polarity occupies practically the same area as the less concentrated following polarity fields, if they are highly integrated. The large difference between Makarov's distribution and other modes of distribution seems to be natural if we take the method of construction into account, and very probably represents its close relationship with the smaller magnetic field elements connected with newer activity, while the other types of distribution demonstrate larger-scale, redistributed, older fields. The areas covered by the positive and negative polarities on the whole Sun during the investigated one and a half solar cycles (No 20 and 21) are practically equal. (author). 5 figs., 10 refs

  9. Latitudinal cogradient variation of development time and growth rate and a negative latitudinal body weight cline in a widely distributed cabbage beetle.

    Directory of Open Access Journals (Sweden)

    Jianjun Tang

    Full Text Available The evolutionary and phenotypic responses to environmental gradients are often assumed to be the same, a phenomenon known as "cogradient variation". However, only a few insect species display cogradient variation in physiological traits along a latitudinal gradient. We found evidence for such a response in the examination of the life history traits of the cabbage beetle Colaphellus bowringi from 6 different geographical populations at 16, 19, 22, 24, 26 and 28°C. Our results showed that larval and pupal development times significantly decreased as rearing temperature increased, and that growth rates were positively correlated with temperature. Body weight tended to decrease with increasing temperature, consistent with the general pattern in ectothermic animals. Larval development time was positively correlated with latitude, whereas the growth rate decreased as latitude increased, showing an example of latitudinal cogradient variation. Body weight significantly decreased with increasing latitude in a stepwise manner, showing a negative latitudinal body weight cline. Females were significantly larger than males, consistent with the female biased sex dimorphism in insects. Body weight tended to decrease with increasing rearing temperature, whereas the differences in sexual size dimorphism (SSD tended to decrease with increasing body weight, which biased our results toward acceptance of Rensch's rule. We found that weight loss was an important regulator of SSD, and because male pupae lost significantly more weight at metamorphosis than female pupae, SSD was greater in adults than in pupae. Overall, our data provide a new example that a latitudinal cogradient variation in physiological traits is associated with a negative latitudinal body weight cline.

  10. Whole genome sequencing of a rare rotavirus from archived stool sample demonstrates independent zoonotic origin of human G8P[14] strains in Hungary.

    Science.gov (United States)

    Marton, Szilvia; Dóró, Renáta; Fehér, Enikő; Forró, Barbara; Ihász, Katalin; Varga-Kugler, Renáta; Farkas, Szilvia L; Bányai, Krisztián

    2017-01-02

    Genotype P[14] rotaviruses in humans are thought to be zoonotic strains originating from bovine or ovine host species. Over the past 30 years only few genotype P[14] strains were identified in Hungary totalinghuman rotaviruses whose genotype had been determined. In this study we report the genome sequence and phylogenetic analysis of a human genotype G8P[14] strain, RVA/Human-wt/HUN/182-02/2001/G8P[14]. The whole genome constellation (G8-P[14]-I2-R2-C2-M2-A11-N2-T6-E2-H3) of this strain was shared with another Hungarian zoonotic G8P[14] strain, RVA/Human-wt/HUN/BP1062/2004/G8P[14], although phylogenetic analyses revealed the two rotaviruses likely had different progenitors. Overall, our findings indicate that human G8P[14] rotavirus detected in Hungary in the past originated from independent zoonotic events. Further studies are needed to assess the public health risk associated with infections by various animal rotavirus strains. Copyright © 2016. Published by Elsevier B.V.

  11. Latitudinal dynamics of SAR-arcs relative to the local time

    International Nuclear Information System (INIS)

    Alekseev, V.N.; Ievenko, I.B.

    1991-01-01

    In November-December, 1988, January-April, 1989-1990, at the Maymaga station in Yakutia according to spectrophotometric data 47 events of the occurrence of red stable middle-latitudinal arcs (SAR-arcs) were recorded. On the basis of these data the latitudinal dynamics of SAR-arcs was studied depending on the local time and geomagnetic disturbance level. The uniform equatorial shift of SAR arcs in the night time is noticed, and a sharp increase of the speed of this motion can be caused by the nonstationary character of the magnetospheric activity

  12. Latitudinal variation of a defensive symbiosis in the Bugula neritina (Bryozoa sibling species complex.

    Directory of Open Access Journals (Sweden)

    Jonathan Linneman

    Full Text Available Mutualistic relationships are beneficial for both partners and are often studied within a single environment. However, when the range of the partners is large, geographical differences in selective pressure may shift the relationship outcome from positive to negative. The marine bryozoan Bugula neritina is a colonial invertebrate common in temperate waters worldwide. It is the source of bioactive polyketide metabolites, the bryostatins. Evidence suggests that an uncultured vertically transmitted symbiont, "Candidatus Endobugula sertula", hosted by B. neritina produces the bryostatins, which protect the vulnerable larvae from predation. Studies of B. neritina along the North American Atlantic coast revealed a complex of two morphologically similar sibling species separated by an apparent biogeographic barrier: the Type S sibling species was found below Cape Hatteras, North Carolina, while Type N was found above. Interestingly, the Type N colonies lack "Ca. Endobugula sertula" and, subsequently, defensive bryostatins; their documented northern distribution was consistent with traditional biogeographical paradigms of latitudinal variation in predation pressure. Upon further sampling of B. neritina populations, we found that both host types occur in wider distribution, with Type N colonies living south of Cape Hatteras, and Type S to the north. Distribution of the symbiont, however, was not restricted to Type S hosts. Genetic and microscopic evidence demonstrates the presence of the symbiont in some Type N colonies, and larvae from these colonies are endowed with defensive bryostatins and contain "Ca. Endobugula sertula". Molecular analysis of the symbiont from Type N colonies suggests an evolutionarily recent acquisition, which is remarkable for a symbiont thought to be transmitted only vertically. Furthermore, most Type S colonies found at higher latitudes lack the symbiont, suggesting that this host-symbiont relationship is more flexible than

  13. Smart trick at the border. Latitudinal control transformer increases import capacity

    International Nuclear Information System (INIS)

    Roggen, M.

    2002-01-01

    Starting in June 2002, energy consumers in the Netherlands can get more electric power from abroad. Without expensive system extensions, TenneT now has some 1000 MW of extra capacity available. And that is not all. Two latitudinal control transformers are able to control the capacity of the link as desired: 16 positions for import, and 16 for export [nl

  14. Functional microarray analysis of nitrogen and carbon cycling genes across an Antarctic latitudinal transect.

    NARCIS (Netherlands)

    Yergeau, E.; Kang, S.; He, Z.; Zhou, J.; Kowalchuk, G.A.

    2007-01-01

    Soil-borne microbial communities were examined via a functional gene microarray approach across a southern polar latitudinal gradient to gain insight into the environmental factors steering soil N- and C-cycling in terrestrial Antarctic ecosystems. The abundance and diversity of functional gene

  15. Defense pattern of Chinese cork oak across latitudinal gradients: influences of ontogeny, herbivory, climate and soil nutrients

    Science.gov (United States)

    Wang, Xiao-Fei; Liu, Jian-Feng; Gao, Wen-Qiang; Deng, Yun-Peng; Ni, Yan-Yan; Xiao, Yi-Hua; Kang, Feng-Feng; Wang, Qi; Lei, Jing-Pin; Jiang, Ze-Ping

    2016-06-01

    Knowledge of latitudinal patterns in plant defense and herbivory is crucial for understanding the mechanisms that govern ecosystem functioning and for predicting their responses to climate change. Using a widely distributed species in East Asia, Quercus variabilis, we aim to reveal defense patterns of trees with respect to ontogeny along latitudinal gradients. Six leaf chemical (total phenolics and total condensed tannin concentrations) and physical (cellulose, hemicellulose, lignin and dry mass concentration) defensive traits as well as leaf herbivory (% leaf area loss) were investigated in natural Chinese cork oak (Q. variabilis) forests across two ontogenetic stages (juvenile and mature trees) along a ~14°-latitudinal gradient. Our results showed that juveniles had higher herbivory values and a higher concentration of leaf chemical defense substances compared with mature trees across the latitudinal gradient. In addition, chemical defense and herbivory in both ontogenetic stages decreased with increasing latitude, which supports the latitudinal herbivory-defense hypothesis and optimal defense theory. The identified trade-offs between chemical and physical defense were primarily determined by environmental variation associated with the latitudinal gradient, with the climatic factors (annual precipitation, minimum temperature of the coldest month) largely contributing to the latitudinal defense pattern in both juvenile and mature oak trees.

  16. Seasonal latitudinal and secular variations in temperature trend - evidence for influence of anthropogenic sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, D E; Schwartz, S E; Wagener, R; Benkovitz, C M [University of California at San Diego, La Jolla, CA (United States). Scripps Institute of Oceanography

    1993-11-19

    Tropospheric aerosols increase the shortwave reflectivity of the Earth-atmosphere system both by scattering light directly, in the absence of clouds, and by enhancing cloud reflectivity. The radiative forcing of climate exerted by anthropogenic sulfate aerosols, derived mainly from SO[sub 2] emitted from fossil fuel combustion, is opposite that due to anthropogenic greenhouse gases and is estimated to be of comparable average magnitude in Northern Hemisphere midlatitudes. However, persuasive evidence of climate response to this forcing has thus far been lacking. Here we examine patterns of seasonal and latitudinal variations in temperature anomaly trend for evidence of such a response. Pronounced minima in the rate of temperature increase in summer months in Northern Hemisphere midlatitudes are consistent with the latitudinal distribution of anthropogenic sulfate and changes in the rate of SO[sub 2] emissions over the industrial era.

  17. ACTN3 allele frequency in humans covaries with global latitudinal gradient.

    Directory of Open Access Journals (Sweden)

    Scott M Friedlander

    Full Text Available A premature stop codon in ACTN3 resulting in α-actinin-3 deficiency (the ACTN3 577XX genotype is common in humans and reduces strength, muscle mass, and fast-twitch fiber diameter, but increases the metabolic efficiency of skeletal muscle. Linkage disequilibrium data suggest that the ACTN3 R577X allele has undergone positive selection during human evolution. The allele has been hypothesized to be adaptive in environments with scarce resources where efficient muscle metabolism would be selected. Here we test this hypothesis by using recently developed comparative methods that account for evolutionary relatedness and gene flow among populations. We find evidence that the ACTN3 577XX genotype evolved in association with the global latitudinal gradient. Our results suggest that environmental variables related to latitudinal variation, such as species richness and mean annual temperature, may have influenced the adaptive evolution of ACTN3 577XX during recent human history.

  18. On the physical causes of ENSO events and the ITCZ's extreme latitudinal displacements

    International Nuclear Information System (INIS)

    Njau, E.C.

    1988-08-01

    We predict the maximum latitudinal shifts of the Inter-Tropical convergence zone (ITCZ) over land masses due to variations in the surface or near-surface temperature fields. We also predict the mean locations of the ITCZ over oceans during northern hemisphere (NH) and southern hemisphere (SH) summers. All our predictions are shown to agree well with observations. Finally, on the basis of the association between the latitudinal location of the eastern pacific portion of the ITCZ and El Nino-Southern Oscillation (ENSO) events as well as some previous related work (Njau, 1985a; 1985b; 1986; 1987; 1988), we suggest possible physical causes of the ENSO events. (author). 39 refs, 1 fig., 2 tabs

  19. Phylogenetic niche conservatism explains an inverse latitudinal diversity gradient in freshwater arthropods

    Science.gov (United States)

    Morinière, Jérôme; van Dam, Matthew H.; Hawlitschek, Oliver; Bergsten, Johannes; Michat, Mariano C.; Hendrich, Lars; Ribera, Ignacio; Toussaint, Emmanuel F. A.; Balke, Michael

    2016-05-01

    The underlying mechanisms responsible for the general increase in species richness from temperate regions to the tropics remain equivocal. Many hypotheses have been proposed to explain this astonishing pattern but additional empirical studies are needed to shed light on the drivers at work. Here we reconstruct the evolutionary history of the cosmopolitan diving beetle subfamily Colymbetinae, the majority of which are found in the Northern hemisphere, hence exhibiting an inversed latitudinal diversity gradient. We reconstructed a dated phylogeny using 12 genes, to investigate the biogeographical history and diversification dynamics in the Colymbetinae. We aimed to identify the role that phylogenetic niche conservatism plays in the inversed diversification pattern seen in this group. Our results suggest that Colymbetinae originated in temperate climates, which supports the hypothesis that their distribution is the result of an ancestral adaptation to temperate environmental conditions rather than tropical origins, and that temperate niche conservatism can generate and/or maintain inverse latitudinal diversity gradients.

  20. Latitudinal and seasonal variations of lower atmospheric inertial gravity wave energy revealed by US radiosonde data

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, S.D.; Yi, F. [Wuhan Univ., Hubei (China). School of Electronic Information; Ministry of Education, Wuhan, Hubei (China). Key Lab. of Geospace Environment and Geodesy; State Observatory for Atmospheric Remote Sensing, Wuhan (China); Huang, C.M. [Wuhan Univ., Hubei (China). School of Electronic Information; Ministry of Education, Wuhan, Hubei (China). Key Lab. of Geospace Environment and Geodesy; State Observatory for Atmospheric Remote Sensing, Wuhan (China); Miami Univ., Oxford, OH (United States). Electrical and Computer Engineering Dept.; Zhou, Q. [Miami Univ., Oxford, OH (United States). Electrical and Computer Engineering Dept.

    2010-07-01

    The latitudinal and seasonal variations of gravity wave (GW) potential energy density (E{sub P}), kinetic energy density (E{sub K}), and total energy density (E{sub T}), i.e, the sum of potential and kinetic energy densities in the tropospheric (typically 2-10 km) and lower stratospheric (typically 18- 25 km) segments have been derived from 10 years (1998- 2007) of radiosonde observations over 92 United States stations in the Northern Hemisphere. The latitudinal variation of E{sub P} in the lower stratosphere is in good agreement with satellite observations. However, E{sub K} and E{sub T} in the lower stratosphere are different from satellite observations and the difference is believed to be linked with the latitudinal dependence of GW sources. Our analysis reveals that GW energy properties exhibit distinctive latitudinal and seasonal variations. The upward-propagating GW energy in the troposphere is larger than that in the lower stratosphere at low latitudes but the opposite holds true at high latitudes. The transition latitude, where the upward- propagating energies in the two altitude regions are the same, occurs at 35 N throughout the year. So striking differences between GW activity in the troposphere and lower stratosphere are not likely explained only by the background wind Doppler shifting due to strong tropospheric jets. Our analysis indicates that the region around tropopause, roughly from 10 km to 18 km, is an important source region, especially at latitudes below 35 N. Our studies strongly suggest that in order to fully understand the global GW activity in the lower atmosphere, the GW kinetic energy and its geographical and seasonal variations should be included, and more attention should be given to GWs in the troposphere and GW sources within the intermediate region, especially the upper troposphere. (orig.)

  1. Latitudinal variation of the topside electron temperature at different levels of solar activity

    Czech Academy of Sciences Publication Activity Database

    Truhlík, Vladimír; Bilitza, D.; Třísková, Ludmila

    2009-01-01

    Roč. 44, č. 6 (2009), s. 693-700 ISSN 0273-1177 R&D Projects: GA AV ČR IAA300420603 Grant - others: NASA (US) NNH06CD17C Institutional research plan: CEZ:AV0Z30420517 Keywords : Electron temperature * Solar activity variation * Latitudinal dependence Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.079, year: 2009

  2. Latitudinal and seasonal variations of lower atmospheric inertial gravity wave energy revealed by US radiosonde data

    Directory of Open Access Journals (Sweden)

    S. D. Zhang

    2010-05-01

    Full Text Available The latitudinal and seasonal variations of gravity wave (GW potential energy density (EP, kinetic energy density (EK, and total energy density (ET, i.e, the sum of potential and kinetic energy densities in the tropospheric (typically 2–10 km and lower stratospheric (typically 18–25 km segments have been derived from 10 years (1998–2007 of radiosonde observations over 92 United States stations in the Northern Hemisphere. The latitudinal variation of EP in the lower stratosphere is in good agreement with satellite observations. However, EK and ET in the lower stratosphere are different from satellite observations and the difference is believed to be linked with the latitudinal dependence of GW sources. Our analysis reveals that GW energy properties exhibit distinctive latitudinal and seasonal variations. The upward-propagating GW energy in the troposphere is larger than that in the lower stratosphere at low latitudes but the opposite holds true at high latitudes. The transition latitude, where the upward- propagating energies in the two altitude regions are the same, occurs at 35° N throughout the year. So striking differences between GW activity in the troposphere and lower stratosphere are not likely explained only by the background wind Doppler shifting due to strong tropospheric jets. Our analysis indicates that the region around tropopause, roughly from 10 km to 18 km, is an important source region, especially at latitudes below 35° N. Our studies strongly suggest that in order to fully understand the global GW activity in the lower atmosphere, the GW kinetic energy and its geographical and seasonal variations should be included, and more attention should be given to GWs in the troposphere and GW sources within the intermediate region, especially the upper troposphere.

  3. Temperature-stress resistance and tolerance along a latitudinal cline in North American Arabidopsis lyrata.

    Directory of Open Access Journals (Sweden)

    Guillaume Wos

    Full Text Available The study of latitudinal gradients can yield important insights into adaptation to temperature stress. Two strategies are available: resistance by limiting damage, or tolerance by reducing the fitness consequences of damage. Here we studied latitudinal variation in resistance and tolerance to frost and heat and tested the prediction of a trade-off between the two strategies and their costliness. We raised plants of replicate maternal seed families from eight populations of North American Arabidopsis lyrata collected along a latitudinal gradient in climate chambers and exposed them repeatedly to either frost or heat stress, while a set of control plants grew under standard conditions. When control plants reached maximum rosette size, leaf samples were exposed to frost and heat stress, and electrolyte leakage (PEL was measured and treated as an estimate of resistance. Difference in maximum rosette size between stressed and control plants was used as an estimate of tolerance. Northern populations were more frost resistant, and less heat resistant and less heat tolerant, but-unexpectedly-they were also less frost tolerant. Negative genetic correlations between resistance and tolerance to the same and different thermal stress were generally not significant, indicating only weak trade-offs. However, tolerance to frost was consistently accompanied by small size under control conditions, which may explain the non-adaptive latitudinal pattern for frost tolerance. Our results suggest that adaptation to frost and heat is not constrained by trade-offs between them. But the cost of frost tolerance in terms of plant size reduction may be important for the limits of species distributions and climate niches.

  4. Tree diversity patterns along the latitudinal gradient in the northwestern Russia

    Directory of Open Access Journals (Sweden)

    Elena Tikhonova

    2017-12-01

    Full Text Available Background One of the key forest characteristics is the biodiversity, particularly the diversity of trees which are forest ecosystem engineers. Nowadays the most worldwide common approach for assessment of forest conditions and dynamics is based on the systematic monitoring, performed at a set of regularly structured plots. To fulfill the existing gap in this sort of knowledge on the Russian forests, an extensive study of tree species diversity on a regular network was conducted in north-west of Russia. Methods The study used the ICP Forests monitoring network that spans over 1700 km along the western Russian border from forest-tundra in the north to broadleaved-coniferous forests in the south. Tree data were collected at 710 sites that were assigned along a regular grid. We performed series of statistical analyses of the tree species distribution and diversity in relation to environmental and anthropogenic factors. Results According to the Maxent species distribution modelling results only Pinus sylvestris, Betula sp. and Picea abies have the potential to grow throughout the study area. The locally maximum tree species diversity varies along the latitudinal gradient from 1 to 3 species in the north to 5–7 species in the south. Monocultural stands are relatively abundant across the study area, being especially common in the south taiga. The prevailing part of the monocultural stands is represented by Scots pine (72%. The age distribution of dominant trees has a clear connection with the intensity of forest use. We found that recent wildfire events had only little effect on tree diversity in the study area. Conclusions We demonstrated that ICP Forests monitoring network enables to successfully establish the main qualitative and quantitative relations of the spatial variation of tree species diversity to climatic, landscape, soil and anthropogenic factors. Analysis of the influence of these factors on tree species distribution allowed us to

  5. Latitudinal Clines of the Human Vitamin D Receptor and Skin Color Genes

    Directory of Open Access Journals (Sweden)

    Dov Tiosano

    2016-05-01

    Full Text Available The well-documented latitudinal clines of genes affecting human skin color presumably arise from the need for protection from intense ultraviolet radiation (UVR vs. the need to use UVR for vitamin D synthesis. Sampling 751 subjects from a broad range of latitudes and skin colors, we investigated possible multilocus correlated adaptation of skin color genes with the vitamin D receptor gene (VDR, using a vector correlation metric and network method called BlocBuster. We discovered two multilocus networks involving VDR promoter and skin color genes that display strong latitudinal clines as multilocus networks, even though many of their single gene components do not. Considered one by one, the VDR components of these networks show diverse patterns: no cline, a weak declining latitudinal cline outside of Africa, and a strong in- vs. out-of-Africa frequency pattern. We confirmed these results with independent data from HapMap. Standard linkage disequilibrium analyses did not detect these networks. We applied BlocBuster across the entire genome, showing that our networks are significant outliers for interchromosomal disequilibrium that overlap with environmental variation relevant to the genes’ functions. These results suggest that these multilocus correlations most likely arose from a combination of parallel selective responses to a common environmental variable and coadaptation, given the known Mendelian epistasis among VDR and the skin color genes.

  6. PHYSIOLOGICAL RESPONSES OF ECKLONIA RADIATA (LAMINARIALES) TO A LATITUDINAL GRADIENT IN OCEAN TEMPERATURE

    DEFF Research Database (Denmark)

    Stæhr, Peter Anton; Wernberg, Thomas

    2009-01-01

    We tested the ability of sporophytes of a small kelp, Ecklonia radiata (C. Agardh) J. Agardh, to adjust their photosynthesis, respiration, and cellular processes to increasingly warm ocean climates along a latitudinal gradient in ocean temperature (~4°C). Tissue concentrations of pigment and nutr......We tested the ability of sporophytes of a small kelp, Ecklonia radiata (C. Agardh) J. Agardh, to adjust their photosynthesis, respiration, and cellular processes to increasingly warm ocean climates along a latitudinal gradient in ocean temperature (~4°C). Tissue concentrations of pigment...... and nutrients decreased with increasing ocean temperature. Concurrently, a number of gradual changes in the metabolic balance of E. radiata took place along the latitudinal gradient. Warm-acclimatized kelps had 50% lower photosynthetic rates and 90% lower respiration rates at the optimum temperature than did...... cool-acclimatized kelps. A reduction in temperature sensitivity was also observed as a reduction in Q10-values from cool- to warm-acclimatized kelps for gross photosynthesis (Q10: 3.35 to 1.45) and respiration (Q10: 3.82 to 1.65). Respiration rates were more sensitive to increasing experimental...

  7. Different Planctomycetes diversity patterns in latitudinal surface seawater of the open sea and in sediment.

    Science.gov (United States)

    Shu, Qinglong; Jiao, Nianzhi

    2008-04-01

    The 16S rRNA gene approach was applied to investigate the diversity of Planctomycetes in latitudinal surface seawater of the Western Pacific Ocean. The results revealed that the Pirellula-Rhodopirellula-Blastopirellula clade dominated the Planctomycetes community at all surface seawater sites while the minority genera Gemmata and Planctomyces were only found at sites H5 and H2 respectively. Although the clone frequency of the PRB clade seemed stable (between 83.3% and 94.1%) for all surface seawater sites, the retrieved Pirellula-Rhodopirellula-Blastopirellula clade presented unexpected diversity. Interestingly, low latitude seawater appeared to have higher diversity than mid-latitudes. integral-LIBSHUFF software analysis revealed significantly different diversity patterns between in latitudinal surface seawater and in the sediment of South China Sea station M2896. Our data suggested that different hydrological and geographic features contributed to the shift of Planctomycetes diversity in marine environments. This is, to our knowledge, the first systematic assessment of Planctomycetes in latitudinal surface seawater of the open sea and the first comparison of diversity pattern between surface seawater and sediments and has broadened our understanding of Planctomycetes diversity in marine environments.

  8. Latitudinal gradient effect on the wing geometry of Auca coctei (Guérin(Lepidoptera, Nymphalidae

    Directory of Open Access Journals (Sweden)

    María-José Sanzana

    2013-12-01

    Full Text Available Latitudinal gradient effect on the wing geometry of Auca coctei (Guérin (Lepidoptera, Nymphalidae. When the environmental conditions change locally, the organisms and populations may also change in response to the selection pressure, so that the development of individuals may become affected in different degrees. There have been only a few studies in which the patterns of wing morphology variation have been looked into along a latitudinal gradient by means of geometric morphometrics. The aim of this work was to assess the morphologic differentiation of wing among butterfly populations of the species Auca coctei. For this purpose, 9 sampling locations were used which are representative of the distribution range of the butterfly and cover a wide latitudinal range in Chile. The wing morphology was studied in a total of 202 specimens of A. coctei (150 males and 52 females, based on digitization of 17 morphologic landmarks. The results show variation of wing shape in both sexes; however, for the centroid size there was significant variation only in females. Females show smaller centroid size at higher latitudes, therefore in this study the Bergmann reverse rule is confirmed for females of A. coctei. Our study extends morphologic projections with latitude, suggesting that wing variation is an environmental response from diverse origins and may influence different characteristics of the life history of a butterfly.

  9. Spatial and Temporal Growth Variation of Pinus heldreichii Christ. Growing along a Latitudinal Gradient in Kosovo and Albania

    OpenAIRE

    Bojaxhi, Faruk; Toromani, Elvin

    2017-01-01

    Background and Purpose: Trees growing at high elevations are particularly sensitive to climate variability. In this study, tree-ring chronologies of Pinus heldreichii Christ. have been developed to examine their dynamism along a 350 km latitudinal gradient. Materials and Methods: Sampling was conducted in 6 high elevation sites along a latitudinal gradient from Kosovo and Albania. Two opposite cores from 148 healthy and dominant P. heldreichii trees were taken using an increment borer. Th...

  10. Hatching response to temperature along a latitudinal gradient by the fairy shrimp Branchinecta lindahli (Crustacea; Branchiopoda; Anostraca in culture conditions

    Directory of Open Access Journals (Sweden)

    D. Christopher Rogers

    2014-08-01

    Full Text Available Branchinecta lindahli is a broadly distributed fairy shrimp, reported from a range of temporary wetland habitat types in arid western North America. This species’ eggs hatch after the habitat dries, refills from seasonal rain, and receives a strong cold shock during the winter low temperatures. I studied phenotypic variation in temperature responses in cultures collected from four populations across 8° of latitude with low average temperatures ranging from -8 to 8°C. Time to maturation, mature body size and first clutch size decreased, as temperature increased, with only minor body size variability at mortality, regardless of culture origin. No variation in individual egg size was observed, demonstrating that body size is sacrificed to produce at least a few normal eggs during unfavourable years. Latitudinal variation in hatching temperature demonstrated a pattern of adaptive significance, with some overlap between regional temperature hatching cues.  Phenotypic hatching temperature and growth rate responses may cause genetic segregation, selecting one cohort for warmer, dryer years and one cohort for cooler, wetter years.  Drier year selected cohorts can exploit habitats that have shorter hydroperiods even in wet years. This may lead to population specialisation and speciation by adapting to more extreme habitats

  11. Dynamical System Modeling to Simulate Donor T Cell Response to Whole Exome Sequencing-Derived Recipient Peptides Demonstrates Different Alloreactivity Potential in HLA-Matched and -Mismatched Donor-Recipient Pairs.

    Science.gov (United States)

    Abdul Razzaq, Badar; Scalora, Allison; Koparde, Vishal N; Meier, Jeremy; Mahmood, Musa; Salman, Salman; Jameson-Lee, Max; Serrano, Myrna G; Sheth, Nihar; Voelkner, Mark; Kobulnicky, David J; Roberts, Catherine H; Ferreira-Gonzalez, Andrea; Manjili, Masoud H; Buck, Gregory A; Neale, Michael C; Toor, Amir A

    2016-05-01

    Immune reconstitution kinetics and subsequent clinical outcomes in HLA-matched recipients of allogeneic stem cell transplantation (SCT) are variable and difficult to predict. Considering SCT as a dynamical system may allow sequence differences across the exomes of the transplant donors and recipients to be used to simulate an alloreactive T cell response, which may allow better clinical outcome prediction. To accomplish this, whole exome sequencing was performed on 34 HLA-matched SCT donor-recipient pairs (DRPs) and the nucleotide sequence differences translated to peptides. The binding affinity of the peptides to the relevant HLA in each DRP was determined. The resulting array of peptide-HLA binding affinity values in each patient was considered as an operator modifying a hypothetical T cell repertoire vector, in which each T cell clone proliferates in accordance with the logistic equation of growth. Using an iterating system of matrices, each simulated T cell clone's growth was calculated with the steady-state population being proportional to the magnitude of the binding affinity of the driving HLA-peptide complex. Incorporating competition between T cell clones responding to different HLA-peptide complexes reproduces a number of features of clinically observed T cell clonal repertoire in the simulated repertoire, including sigmoidal growth kinetics of individual T cell clones and overall repertoire, Power Law clonal frequency distribution, increase in repertoire complexity over time with increasing clonal diversity, and alteration of clonal dominance when a different antigen array is encountered, such as in SCT. The simulated, alloreactive T cell repertoire was markedly different in HLA-matched DRPs. The patterns were differentiated by rate of growth and steady-state magnitude of the simulated T cell repertoire and demonstrate a possible correlation with survival. In conclusion, exome wide sequence differences in DRPs may allow simulation of donor alloreactive T

  12. Impact of snow deposition on major and trace element concentrations and elementary fluxes in surface waters of the Western Siberian Lowland across a 1700 km latitudinal gradient

    Science.gov (United States)

    Shevchenko, Vladimir P.; Pokrovsky, Oleg S.; Vorobyev, Sergey N.; Krickov, Ivan V.; Manasypov, Rinat M.; Politova, Nadezhda V.; Kopysov, Sergey G.; Dara, Olga M.; Auda, Yves; Shirokova, Liudmila S.; Kolesnichenko, Larisa G.; Zemtsov, Valery A.; Kirpotin, Sergey N.

    2017-11-01

    In order to better understand the chemical composition of snow and its impact on surface water hydrochemistry in the poorly studied Western Siberia Lowland (WSL), the surface layer of snow was sampled in February 2014 across a 1700 km latitudinal gradient (ca. 56.5 to 68° N). We aimed at assessing the latitudinal effect on both dissolved and particulate forms of elements in snow and quantifying the impact of atmospheric input to element storage and export fluxes in inland waters of the WSL. The concentration of dissolved+colloidal (metalloids (As, Sb), Mo and U in the discontinuous to continuous permafrost zone (64-68° N) can be explained solely by melting of accumulated snow. The impact of snow deposition on riverine fluxes of elements strongly increased northward, in discontinuous and continuous permafrost zones of frozen peat bogs. This was consistent with the decrease in the impact of rock lithology on river chemical composition in the permafrost zone of the WSL, relative to the permafrost-free regions. Therefore, the present study demonstrates significant and previously underestimated atmospheric input of many major and trace elements to their riverine fluxes during spring floods. A broader impact of this result is that current estimations of river water fluxes response to climate warming in high latitudes may be unwarranted without detailed analysis of winter precipitation.

  13. Tested Demonstrations.

    Science.gov (United States)

    Gilbert, George L.

    1983-01-01

    An apparatus is described in which effects of pressure, volume, and temperature changes on a gas can be observed simultaneously. Includes use of the apparatus in demonstrating Boyle's, Gay-Lussac's, and Charles' Laws, attractive forces, Dalton's Law of Partial pressures, and in illustrating measurable vapor pressures of liquids and some solids.…

  14. Tested Demonstrations.

    Science.gov (United States)

    Gilbert, George L., Ed.

    1987-01-01

    Describes two demonstrations to illustrate characteristics of substances. Outlines a method to detect the changes in pH levels during the electrolysis of water. Uses water pistols, one filled with methane gas and the other filled with water, to illustrate the differences in these two substances. (TW)

  15. Faster speciation and reduced extinction in the tropics contribute to the Mammalian latitudinal diversity gradient.

    Directory of Open Access Journals (Sweden)

    Jonathan Rolland

    2014-01-01

    Full Text Available The increase in species richness from the poles to the tropics, referred to as the latitudinal diversity gradient, is one of the most ubiquitous biodiversity patterns in the natural world. Although understanding how rates of speciation and extinction vary with latitude is central to explaining this pattern, such analyses have been impeded by the difficulty of estimating diversification rates associated with specific geographic locations. Here, we use a powerful phylogenetic approach and a nearly complete phylogeny of mammals to estimate speciation, extinction, and dispersal rates associated with the tropical and temperate biomes. Overall, speciation rates are higher, and extinction rates lower, in the tropics than in temperate regions. The diversity of the eight most species-rich mammalian orders (covering 92% of all mammals peaks in the tropics, except that of the Lagomorpha (hares, rabbits, and pikas reaching a maxima in northern-temperate regions. Latitudinal patterns in diversification rates are strikingly consistent with these diversity patterns, with peaks in species richness associated with low extinction rates (Primates and Lagomorpha, high speciation rates (Diprotodontia, Artiodactyla, and Soricomorpha, or both (Chiroptera and Rodentia. Rates of range expansion were typically higher from the tropics to the temperate regions than in the other direction, supporting the "out of the tropics" hypothesis whereby species originate in the tropics and disperse into higher latitudes. Overall, these results suggest that differences in diversification rates have played a major role in shaping the modern latitudinal diversity gradient in mammals, and illustrate the usefulness of recently developed phylogenetic approaches for understanding this famous yet mysterious pattern.

  16. Latitudinal and seasonal capacity of the surface oceans as a reservoir of polychlorinated biphenyls

    International Nuclear Information System (INIS)

    Jurado, Elena; Lohmann, Rainer; Meijer, Sandra; Jones, Kevin C.; Dachs, Jordi

    2004-01-01

    The oceans play an important role as a global reservoir and ultimate sink of persistent organic pollutants (POPs) such as polychlorinated biphenyls congeners (PCBs). However, the physical and biogeochemical variables that affect the oceanic capacity to retain PCBs show an important spatial and temporal variability which have not been studied in detail, so far. The objective of this paper is to assess the seasonal and spatial variability of the ocean's maximum capacity to act as a reservoir of atmospherically transported and deposited PCBs. A level I fugacity model is used which incorporates the environmental variables of temperature, phytoplankton biomass, and mixed layer depth, as determined from remote sensing and from climatological datasets. It is shown that temperature, phytoplankton biomass and mixed layer depth influence the potential PCB reservoir of the oceans, being phytoplankton biomass specially important in the oceanic productive regions. The ocean's maximum capacities to hold PCBs are estimated. They are compared to a budget of PCBs in the surface oceans derived using a level III model that assumes steady state and which incorporates water column settling fluxes as a loss process. Results suggest that settling fluxes will keep the surface oceanic reservoir of PCBs well below its maximum capacity, especially for the more hydrophobic compounds. The strong seasonal and latitudinal variability of the surface ocean's storage capacity needs further research, because it plays an important role in the global biogeochemical cycles controlling the ultimate sink of PCBs. Because this modeling exercise incorporates variations in downward fluxes driven by phytoplankton and the extent of the water column mixing, it predicts more complex latitudinal variations in PCBs concentrations than those previously suggested. - Model calculations estimate the latitudinal and seasonal storage capacity of the surface oceans for PCBs

  17. Latitudinal variation in seasonal activity and mortality in ratsnakes (Elaphe obsoleta).

    Science.gov (United States)

    Sperry, Jinelle H; Blouin-Demers, Gabriel; Carfagno, Gerardo L F; Weatherhead, Patrick J

    2010-06-01

    The ecology of ectotherms should be particularly affected by latitude because so much of their biology is temperature dependent. Current latitudinal patterns should also be informative about how ectotherms will have to modify their behavior in response to climate change. We used data from a total of 175 adult black ratsnakes (Elaphe obsoleta) radio-tracked in Ontario, Illinois, and Texas, a latitudinal distance of >1500 km, to test predictions about how seasonal patterns of activity and mortality should vary with latitude. Despite pronounced differences in temperatures among study locations, and despite ratsnakes in Texas not hibernating and switching from diurnal to nocturnal activity in the summer, seasonal patterns of snake activity were remarkably similar during the months that snakes in all populations were active. Rather than being a function of temperature, activity may be driven by the timing of reproduction, which appears similar among populations. Contrary to the prediction that mortality should be highest in the most active population, overall mortality did not follow a clinal pattern. Winter mortality did increase with latitude, however, consistent with temperature limiting the northern distribution of ratsnakes. This result was opposite that found in the only previous study of latitudinal variation in winter mortality in reptiles, which may be a consequence of whether or not the animals exhibit true hibernation. Collectively, these results suggest that, at least in the northern part of their range, ratsnakes should be able to adjust easily to, and may benefit from, a warmer climate, although climate-based changes to the snakes' prey or habitat, for example, could alter that prediction.

  18. Investigation of Seasonal and Latitudinal Effects on the Expression of Clock Genes in Drosophila

    Science.gov (United States)

    Hosseini, Seyede Sanaz; Nazarimehr, Fahimeh; Jafari, Sajad

    The primary goal in this work is to develop a dynamical model capturing the influence of seasonal and latitudinal variations on the expression of Drosophila clock genes. To this end, we study a specific dynamical system with strange attractors that exhibit changes of Drosophila activity in a range of latitudes and across different seasons. Bifurcations of this system are analyzed to peruse the effect of season and latitude on the behavior of clock genes. Existing experimental data collected from the activity of Drosophila melanogaster corroborate the dynamical model.

  19. Latitudinal discontinuity in thermal conditions along the nearshore of central-northern Chile.

    Science.gov (United States)

    Tapia, Fabian J; Largier, John L; Castillo, Manuel; Wieters, Evie A; Navarrete, Sergio A

    2014-01-01

    Over the past decade, evidence of abrupt latitudinal changes in the dynamics, structure and genetic variability of intertidal and subtidal benthic communities along central-northern Chile has been found consistently at 30-32°S. Changes in the advective and thermal environment in nearshore waters have been inferred from ecological patterns, since analyses of in situ physical data have thus far been missing. Here we analyze a unique set of shoreline temperature data, gathered over 4-10 years at 15 sites between 28-35°S, and combine it with satellite-derived winds and sea surface temperatures to investigate the latitudinal transition in nearshore oceanographic conditions suggested by recent ecological studies. Our results show a marked transition in thermal conditions at 30-31°S, superimposed on a broad latitudinal trend, and small-scale structures associated with cape-and-bay topography. The seasonal cycle dominated temperature variability throughout the region, but its relative importance decreased abruptly south of 30-31°S, as variability at synoptic and intra-seasonal scales became more important. The response of shoreline temperatures to meridional wind stress also changed abruptly at the transition, leading to a sharp drop in the occurrence of low-temperature waters at northern sites, and a concurrent decrease in corticated algal biomass. Together, these results suggest a limitation of nitrate availability in nearshore waters north of the transition. The localized alongshore change results from the interaction of latitudinal trends (e.g., wind stress, surface warming, inertial period) with a major headland-bay system (Punta Lengua de Vaca at 30.25°S), which juxtaposes a southern stretch of coast characterized by upwelling with a northern stretch of coast characterized by warm surface waters and stratification. This transition likely generates a number of latitude-dependent controls on ecological processes in the nearshore that can explain species

  20. Assessment of tannin variation in Tamarisk foliage across a latitudinal gradient

    Science.gov (United States)

    Hussey, A.M.; Kimball, B.A.; Friedman, J.M.

    2011-01-01

    Certain phenotypic traits of plants vary with latitude of origin. To understand if tannin concentration varies among populations of tamarisk (Tamarix spp.) according to a latitudinal gradient, an analytical method was adapted from an enological tannin assay. The tannin content (wet basis) of tamarisk foliage collected from 160 plants grown in a common garden ranged from 8.26 to 62.36 mg/g and was not correlated with the latitude of the original North American plant collection site. Tannins do not contribute to observed differences in herbivory observed among these tamarisk populations.

  1. Latitudinal Trends in Abundant and Rare Bacterioplankton Community Structure and Diversity in Surface Waters of the Pacific Ocean

    Science.gov (United States)

    Jeffrey, W. H.; Moss, J. A.; Snyder, R.; Pakulski, J. D.

    2016-02-01

    To fully comprehend planktonic diversity and the roles of microorganisms in global biogeochemical cycling, we must recognize the distribution patterns of planktonic taxa and phylotypes and their controlling environmental factors. To advance this understanding, Illumina sequencing targeting the 16S rRNA gene was used to evaluate latitudinal patterns of bacterial taxa as well as diversity in surface waters in the Pacific Ocean. Surface water was collected at 37 stations at 370 km intervals in a 16,200 km transect from 71 N to 68 S in the Pacific Ocean from August to November 2003. These samples were collected on Sterivex filters and kept continuously at -80 C until recent processing which produced over 200k reads per site, half of which were discernible down to the genus level. Bray-Curtis analysis of known genera produced 4 major clusters—sub-Arctic/Arctic, tropical, temperate, and sub-Antarctic/Antarctic. Analysis of only the rare (< 1%) genera produced the same 4 major clusters, although the clusters were most congruent in their geographic distribution when only the abundant taxa were included. Key phyla responsible for these groupings include genera of the Proteobacteria and Cyanobacteria, and as expected, include the pronounced presence of Prochlorococcus in the temperate and equatorial regions. However, many robust trends such as unipolar and bipolar distribution in both the abundant (≥1%) and rare (< 1%) genera within phyla Verrucomicrobia, Actinobacteria, and Barteriodetes, were also apparent. The data sheds light on distribution patterns of the Oleibacter, Thalassobius, Olleya, Salegentibacter, Ulvibacter, Bizionia, Pirellula, and many other additional, understudied genera. Of the 655 identified genera, no significant gradients in gamma diversity were apparent when 12 commonly used species and phylogenetic indices were applied.

  2. Intra-Specific Latitudinal Clines in Leaf Carbon, Nitrogen, and Phosphorus and their Underlying Abiotic Correlates in Ruellia Nudiflora.

    Science.gov (United States)

    Abdala-Roberts, Luis; Covelo, Felisa; Parra-Tabla, Víctor; Terán, Jorge C Berny Mier Y; Mooney, Kailen A; Moreira, Xoaquín

    2018-01-12

    While plant intra-specific variation in the stoichiometry of nutrients and carbon is well documented, clines for such traits have been less studied, despite their potential to reveal the mechanisms underlying such variation. Here we analyze latitudinal variation in the concentration of leaf nitrogen (N), phosphorus (P), carbon (C) and their ratios across 30 populations of the perennial herb Ruellia nudiflora. In addition, we further determined whether climatic and soil variables underlie any such latitudinal clines in leaf traits. The sampled transect spanned 5° latitude (ca. 900 km) and exhibited a four-fold precipitation gradient and 2 °C variation in mean annual temperature. We found that leaf P concentration increased with precipitation towards lower latitudes, whereas N and C did not exhibit latitudinal clines. In addition, N:P and C:P decreased towards lower latitudes and latitudinal variation in the former was weakly associated with soil conditions (clay content and cation exchange capacity); C:N did not exhibit a latitudinal gradient. Overall, these results emphasize the importance of addressing and disentangling the simultaneous effects of abiotic factors associated with intra-specific clines in plant stoichiometric traits, and highlight the previously underappreciated influence of abiotic factors on plant nutrients operating under sharp abiotic gradients over smaller spatial scales.

  3. Speciation and the Latitudinal Diversity Gradient: Insights from the Global Distribution of Endemic Fish.

    Science.gov (United States)

    Hanly, Patrick J; Mittelbach, Gary G; Schemske, Douglas W

    2017-06-01

    The nearly universal pattern that species richness increases from the poles to the equator (the latitudinal diversity gradient [LDG]) has been of intense interest since its discovery by early natural-history explorers. Among the many hypotheses proposed to explain the LDG, latitudinal variation in (1) productivity, (2) time and area available for diversification, and (3) speciation and/or extinction rates have recently received the most attention. Because tropical regions are older and were formerly more widespread, these factors are often intertwined, hampering efforts to distinguish their relative contributions to the LDG. Here we examine the global distribution of endemic lake fishes to determine how lake age, area, and latitude each affect the probability of speciation and the extent of diversification occurring within a lake. We analyzed the distribution of endemic fishes worldwide (1,933 species and subspecies from 47 families in 2,746 lakes) and find that the probability of a lake containing an endemic species and the total number of endemics per lake increase with lake age and area and decrease with latitude. Moreover, the geographic locations of endemics in 34 of 41 families are found at lower latitudes than those of nonendemics. We propose that the greater diversification of fish at low latitudes may be driven in part by ecological opportunities promoted by tropical climates and by the coevolution of species interactions.

  4. A Latitudinal Diversity Gradient in Terrestrial Bacteria of the Genus Streptomyces

    Directory of Open Access Journals (Sweden)

    Cheryl P. Andam

    2016-04-01

    Full Text Available We show that Streptomyces biogeography in soils across North America is influenced by the regional diversification of microorganisms due to dispersal limitation and genetic drift. Streptomyces spp. form desiccation-resistant spores, which can be dispersed on the wind, allowing for a strong test of whether dispersal limitation governs patterns of terrestrial microbial diversity. We employed an approach that has high sensitivity for determining the effects of genetic drift. Specifically, we examined the genetic diversity and phylogeography of physiologically similar Streptomyces strains isolated from geographically distributed yet ecologically similar habitats. We found that Streptomyces beta diversity scales with geographic distance and both beta diversity and phylogenetic diversity manifest in a latitudinal diversity gradient. This pattern of Streptomyces biogeography resembles patterns seen for diverse species of plants and animals, and we therefore evaluated these data in the context of ecological and evolutionary hypotheses proposed to explain latitudinal diversity gradients. The data are consistent with the hypothesis that niche conservatism limits dispersal, and historical patterns of glaciation have limited the time for speciation in higher-latitude sites. Most notably, higher-latitude sites have lower phylogenetic diversity, higher phylogenetic clustering, and evidence of range expansion from lower latitudes. In addition, patterns of beta diversity partition with respect to the glacial history of sites. Hence, the data support the hypothesis that extant patterns of Streptomyces biogeography have been driven by historical patterns of glaciation and are the result of demographic range expansion, dispersal limitation, and regional diversification due to drift.

  5. A Latitudinal Diversity Gradient in Terrestrial Bacteria of the Genus Streptomyces

    Science.gov (United States)

    Andam, Cheryl P.; Doroghazi, James R.; Campbell, Ashley N.; Kelly, Peter J.; Choudoir, Mallory J.

    2016-01-01

    ABSTRACT We show that Streptomyces biogeography in soils across North America is influenced by the regional diversification of microorganisms due to dispersal limitation and genetic drift. Streptomyces spp. form desiccation-resistant spores, which can be dispersed on the wind, allowing for a strong test of whether dispersal limitation governs patterns of terrestrial microbial diversity. We employed an approach that has high sensitivity for determining the effects of genetic drift. Specifically, we examined the genetic diversity and phylogeography of physiologically similar Streptomyces strains isolated from geographically distributed yet ecologically similar habitats. We found that Streptomyces beta diversity scales with geographic distance and both beta diversity and phylogenetic diversity manifest in a latitudinal diversity gradient. This pattern of Streptomyces biogeography resembles patterns seen for diverse species of plants and animals, and we therefore evaluated these data in the context of ecological and evolutionary hypotheses proposed to explain latitudinal diversity gradients. The data are consistent with the hypothesis that niche conservatism limits dispersal, and historical patterns of glaciation have limited the time for speciation in higher-latitude sites. Most notably, higher-latitude sites have lower phylogenetic diversity, higher phylogenetic clustering, and evidence of range expansion from lower latitudes. In addition, patterns of beta diversity partition with respect to the glacial history of sites. Hence, the data support the hypothesis that extant patterns of Streptomyces biogeography have been driven by historical patterns of glaciation and are the result of demographic range expansion, dispersal limitation, and regional diversification due to drift. PMID:27073097

  6. The latitudinal inventory of sup(137)Cs in vegetation and topsoil in northern Canada, 1980

    International Nuclear Information System (INIS)

    Hutchison-Benson, E.; Svoboda, J.; Taylor, H.W.

    1985-01-01

    The latitudinal distribution of fallout sup(137)Cs in Canada has been determined along a transect extending from 50 degrees to 82 degrees N in 1980. The sup(137)Cs content of lichens, bryophytes, and cushionlike vascular species was measured at 16 sites between Brandon, Manitoba, and Alert, Ellesmere Island. Lichen species were shown to be the most effecive biological monitors of sup(137)Cs deposition because of their specific morphology, longevity, and slow growth rates. Dry, exposed ridges were the sites of the highest sup(137)Cs retention by plants. sup(137)Cs levels in vegetation followed a bell-shaped distribution along the transect and the maximum accumulation was measured in samples collected between 60 degrees and 70 degrees N ((10 nCi msup(-2) at 63 degrees N) (1 Ci = 37 GBq). This distribution is the combined results of the original latitudinal deposition of sup(137)Cs, the expired portion of its physical half-life, and the efficiency of biotic and abiotic removal processes along the studied corridor. It is suggested that the long-term implications of sup(137)Cs in the northern food chain ought to be followed and studied more closely in the light of the data presented

  7. Asymmetric changes of growth and reproductive investment herald altitudinal and latitudinal range shifts of two woody species.

    Science.gov (United States)

    Matías, Luis; Jump, Alistair S

    2015-02-01

    Ongoing changes in global climate are altering ecological conditions for many species. The consequences of such changes are typically most evident at the edge of the geographical distribution of a species, where range expansions or contractions may occur. Current demographical status at geographical range limits can help us to predict population trends and their implications for the future distribution of the species. Thus, understanding the comparability of demographical patterns occurring along both altitudinal and latitudinal gradients would be highly informative. In this study, we analyse the differences in the demography of two woody species through altitudinal gradients at their southernmost distribution limit and the consistency of demographical patterns at the treeline across a latitudinal gradient covering the complete distribution range. We focus on Pinus sylvestris and Juniperus communis, assessing their demographical structure (density, age and mortality rate), growth, reproduction investment and damage from herbivory on 53 populations covering the upper, central and lower altitudes as well as the treeline at central latitude and northernmost and southernmost latitudinal distribution limits. For both species, populations at the lowermost altitude presented older age structure, higher mortality, decreased growth and lower reproduction when compared to the upper limit, indicating higher fitness at the treeline. This trend at the treeline was generally maintained through the latitudinal gradient, but with a decreased growth at the northern edge for both species and lower reproduction for P. sylvestris. However, altitudinal and latitudinal transects are not directly comparable as factors other than climate, including herbivore pressure or human management, must be taken into account if we are to understand how to infer latitudinal processes from altitudinal data. © 2014 John Wiley & Sons Ltd.

  8. Range-wide latitudinal and elevational temperature gradients for the world's terrestrial birds: implications under global climate change.

    Directory of Open Access Journals (Sweden)

    Frank A La Sorte

    Full Text Available Species' geographical distributions are tracking latitudinal and elevational surface temperature gradients under global climate change. To evaluate the opportunities to track these gradients across space, we provide a first baseline assessment of the steepness of these gradients for the world's terrestrial birds. Within the breeding ranges of 9,014 bird species, we characterized the spatial gradients in temperature along latitude and elevation for all and a subset of bird species, respectively. We summarized these temperature gradients globally for threatened and non-threatened species and determined how their steepness varied based on species' geography (range size, shape, and orientation and projected changes in temperature under climate change. Elevational temperature gradients were steepest for species in Africa, western North and South America, and central Asia and shallowest in Australasia, insular IndoMalaya, and the Neotropical lowlands. Latitudinal temperature gradients were steepest for extratropical species, especially in the Northern Hemisphere. Threatened species had shallower elevational gradients whereas latitudinal gradients differed little between threatened and non-threatened species. The strength of elevational gradients was positively correlated with projected changes in temperature. For latitudinal gradients, this relationship only held for extratropical species. The strength of latitudinal gradients was better predicted by species' geography, but primarily for extratropical species. Our findings suggest threatened species are associated with shallower elevational temperature gradients, whereas steep latitudinal gradients are most prevalent outside the tropics where fewer bird species occur year-round. Future modeling and mitigation efforts would benefit from the development of finer grain distributional data to ascertain how these gradients are structured within species' ranges, how and why these gradients vary among

  9. The influence of band sum area, domain extent, and range sizes on the latitudinal mid-domain effect

    DEFF Research Database (Denmark)

    Romdal, Tom Skovlund; Colwell, Robert K.; Rahbek, Carsten

    2005-01-01

    of latitudinal distributions of New World birds (3706 species) on a 1° scale. Two previously published data sets for other taxa are also considered. We adjusted band sums (number of species per latitudinal band) for longitudinal area by constructing species-area curves for each band. Area-corrected richness...... patterns differed substantially from raw band sums, although both confirmed a strong, mid-tropical peak in richness. An MDE model accounted for 47% of the adjusted pattern, whereas area alone explained 13% of variation. Area-adjusted band sum data proved preferable to coastal transect data from the same...

  10. Disentangling the drivers of ß diversity along latitudinal and elevational gradients

    DEFF Research Database (Denmark)

    Kraft, Nathan J. B.; Comita, Liza S.; Chase, Jonathan M.

    2011-01-01

    that sampling alone predicts changes in ß diversity caused simply by changes in the sizes of species pools. For example, forest inventories sampled along latitudinal and elevational gradients show the well-documented pattern that ß diversity is higher in the tropics and at low elevations. However, after......Understanding spatial variation in biodiversity along environmental gradients is a central theme in ecology. Differences in species compositional turnover among sites (ß diversity) occurring along gradients are often used to infer variation in the processes structuring communities. Here, we show...... correcting for variation in pooled species richness (¿ diversity), these differences in ß diversity disappear. Therefore, there is no need to invoke differences in the mechanisms of community assembly in temperate versus tropical systems to explain these global-scale patterns of ß diversity....

  11. Latitudinal variation of diversity in European freshwater animals is not concordant across habitat types

    DEFF Research Database (Denmark)

    Hof, Christian; Brändle, Martin; Brandl, Roland

    2008-01-01

    Aim We analysed the variation of species richness in the European freshwater fauna across latitude. In particular, we compared latitudinal patterns in species richness and ß -diversity among species adapted to different habitat types. Location Europe. Methods We compiled data on occurrence for 14......,020 animal species across 25 pre-defined biogeographical regions of European freshwaters from the Limnofauna Europaea . Furthermore, we extracted information on the habitat preferences of species. We assigned species to three habitat types: species adapted to groundwater, lotic (running water) and lentic...... richness among species adapted to different habitat types are in part due to differences in the propensity for dispersal. Since lentic habitats are less persistent than lotic or groundwater habitats, lentic species evolved more efficient strategies for dispersal. The dispersal propensity of lentic species...

  12. Latitudinal environmental gradients and diel variability influence abundance and community structure of Chaetognatha in Red Sea coral reefs

    KAUST Repository

    Al-aidaroos, Ali M.; Karati, Kusum K.; El-sherbiny, Mohsen M.; Devassy, Reny P.; Kü rten, Benjamin

    2016-01-01

    is known about the zooplankton biodiversity of the Red Sea and how this relates to Red Sea latitudinal gradients. Among the most abundant zooplankton taxa are Chaetognatha, which play an important role as secondary consumers in most marine food webs. Since

  13. Environmental Factors Correlated with the Metabolite Profile of Vitis vinifera cv. Pinot Noir Berry Skins along a European Latitudinal Gradient

    Czech Academy of Sciences Publication Activity Database

    Del-Castillo-Alonso, M. Á.; Castagna, A.; Csepregi, K.; Hideg, É.; Jakab, G.; Jansen, M. A. K.; Jug, T.; Llorens, L.; Mátai, A.; Martínez-Lüscher, J.; Monforte, L.; Neugart, S.; Olejníčková, Julie; Ranieri, A.; Schödl-Hummel, K.; Schreiner, M.; Soriano, G.; Teszlák, P.; Tittmann, S.; Urban, Otmar; Verdaguer, D.; Zipoli, G.; Martínez-Abaigar, J.; Núñez-Olivera, E.

    2016-01-01

    Roč. 64, č. 46 (2016), s. 8722-8734 ISSN 0021-8561 Institutional support: RVO:67179843 Keywords : berry skins * Europe * hydroxylation ratios * latitudinal gradient * phenolic composition * solar radiation * ultraviolet radiation * Vitis vinifera cv. Pinot Noir Subject RIV: EH - Ecology, Behaviour Impact factor: 3.154, year: 2016

  14. Asymmetric responses to simulated global warming by populations of Colobanthus quitensis along a latitudinal gradient

    Directory of Open Access Journals (Sweden)

    Ian S. Acuña-Rodríguez

    2017-09-01

    Full Text Available The increase in temperature as consequence of the recent global warming has been reported to generate new ice-free areas in the Antarctic continent, facilitating the colonization and spread of plant populations. Consequently, Antarctic vascular plants have been observed extending their southern distribution. But as the environmental conditions toward southern localities become progressively more departed from the species’ physiological optimum, the ecophysiological responses and survival to the expected global warming could be reduced. However, if processes of local adaptation are the main cause of the observed southern expansion, those populations could appear constrained to respond positively to the expected global warming. Using individuals from the southern tip of South America, the South Shetland Islands and the Antarctic Peninsula, we assess with a long term experiment (three years under controlled conditions if the responsiveness of Colobanthus quitensis populations to the expected global warming, is related with their different foliar traits and photoprotective mechanisms along the latitudinal gradient. In addition, we tested if the release of the stress condition by the global warming in these cold environments increases the ecophysiological performance. For this, we describe the latitudinal pattern of net photosynthetic capacity, biomass accumulation, and number of flowers under current and future temperatures respective to each site of origin after three growing seasons. Overall, was found a clinal trend was found in the foliar traits and photoprotective mechanisms in the evaluated C. quitensis populations. On the other hand, an asymmetric response to warming was observed for southern populations in all ecophysiological traits evaluated, suggesting that low temperature is limiting the performance of C. quitensis populations. Our results suggest that under a global warming scenario, plant populations that inhabiting cold zones at

  15. Latitudinal profile of the ionospheric disturbance dynamo magnetic signature: comparison with the DP2 magnetic disturbance

    Directory of Open Access Journals (Sweden)

    K. Z. Zaka

    2009-09-01

    Full Text Available During magnetic storms, the auroral electrojets intensification affects the thermospheric circulation on a global scale. This process which leads to electric field and current disturbance at middle and low latitudes, on the quiet day after the end of a storm, has been attributed to the ionospheric disturbance dynamo (Ddyn. The magnetic field disturbance observed as a result of this process is the reduction of the H component amplitude in the equatorial region which constitutes the main characteristic of the ionospheric disturbance dynamo process, associated with a westward electric current flow. The latitudinal profile of the Ddyn disturbance dynamo magnetic signature exhibits an eastward current at mid latitudes and a westward one at low latitudes with a substantial amplification at the magnetic equator. Such current flow reveals an "anti-Sq" system established between the mid latitudes and the equatorial region and opposes the normal Sq current vortex. However, the localization of the eastward current and consequently the position and the extent of the "anti-Sq" current vortex changes from one storm to another. Indeed, for a strong magnetic storm, the eastward current is well established at mid latitudes about 45° N and for a weak magnetic storm, the eastward current is established toward the high latitudes (about 60° N, near the Joule heating region, resulting in a large "anti-Sq" current cell. The latitudinal profile of the Ddyn disturbance as well as the magnetic disturbance DP2 generated by the mechanism of prompt penetration of the magnetospheric convection electric field in general, show a weak disturbance at the low latitudes with a substantial amplification at the magnetic equator. Due to the intensity of the storm, the magnitude of the DP2 appears higher than the Ddyn over the American and Asian sector contrary to the African sector.

  16. Latitudinal range influences the seasonal variation in the foraging behavior of marine top predators.

    Directory of Open Access Journals (Sweden)

    Stella Villegas-Amtmann

    Full Text Available Non-migratory resident species should be capable of modifying their foraging behavior to accommodate changes in prey abundance and availability associated with a changing environment. Populations that are better adapted to change will have higher foraging success and greater potential for survival in the face of climate change. We studied two species of resident central place foragers from temperate and equatorial regions with differing population trends and prey availability associated to season, the California sea lion (Zalophus californianus (CSL whose population is increasing and the endangered Galapagos sea lion (Zalophus wollebaeki (GSL whose population is declining. To determine their response to environmental change, we studied and compared their diving behavior using time-depth recorders and satellite location tags and their diet by measuring C and N isotope ratios during a warm and a cold season. Based on latitudinal differences in oceanographic productivity, we hypothesized that the seasonal variation in foraging behavior would differ for these two species. CSL exhibited greater seasonal variability in their foraging behavior as seen in changes to their diving behavior, foraging areas and diet between seasons. Conversely, GSL did not change their diving behavior between seasons, presenting three foraging strategies (shallow, deep and bottom divers during both. GSL exhibited greater dive and foraging effort than CSL. We suggest that during the warm and less productive season a greater range of foraging behaviors in CSL was associated with greater competition for prey, which relaxed during the cold season when resource availability was greater. GSL foraging specialization suggests that resources are limited throughout the year due to lower primary production and lower seasonal variation in productivity compared to CSL. These latitudinal differences influence their foraging success, pup survival and population growth reflected in

  17. Leaf ultraviolet optical properties along a latitudinal gradient in the Arctic-Alpine life zone

    International Nuclear Information System (INIS)

    Robberecht, R.; Caldwell, M.M.; Billings, W.D.

    1980-01-01

    Leaf epidermal transmittance of terrestrial solar ultraviolet-B radiation (295 to 320 nm) was examined along a latitudinal gradient of solar uv-B radiation. In high uv-B radiation zones, e.g., equatorial and tropical regions, mean epidermal transmittance for the species examined was less than 2%. At higher latitudes, mean epidermal transmittance exceeded 5%. Although this latitudinal solar uv-B gradient represents more than a seven-fold difference in daily integrated uv-B irradiance, the calculated mean effective uv-B irradiance at the mesophyll of low-latitude species is not substantially different from that of species at higher latitudes. Species in high uv-B radiation environments appear to attenuate this radiation more effectively than those in lower irradiance environments. In most cases, absorption of uv-B in the epidermis is the major parameter effecting low transmittance. Reflectance from glabrous leaves is generally less than 10%. In some species, pubescent or glaucous leaf surfaces can reflect more than 40% of the uv-B radiation incident on a horizontal leaf, although such surface characteristics do not necessarily indicate high uv-B reflectance. Under controlled conditions, epidermal transmittance in Pisum sativum L. decreased in response to uv-B irradiation. The modification of epidermal transmittance, resulting in lower uv-B irradiance at the mesophyll, may represent a mechanism of plant acclimation to uv-B radiation. Such acclimation may have occurred in several wildland species of temperate-latitude origin that have invaded high uv-B irradiance equatorial and tropical regions

  18. Latitudinal and interhemispheric variation of stratospheric effects on mesospheric ice layer trends

    Science.gov (United States)

    Lübken, F.-J.; Berger, U.

    2011-02-01

    Latitudinal and interhemispheric differences of model results on trends in mesospheric ice layers and background conditions are analyzed. The model nudges to European Centre for Medium-Range Weather Forecasts data below ˜45 km. Greenhouse gas concentrations in the mesosphere are kept constant. Temperature trends in the mesosphere mainly come from shrinking of the stratosphere and from dynamical effects. Water vapor increases at noctilucent cloud (NLC) heights and decreases above due to increased freeze drying caused by temperature trends. There is no tendency for ice clouds in the Northern Hemisphere for extending farther southward with time. Trends of NLC albedo are similar to satellite measurements, but only if a time period longer than observations is considered. Ice cloud trends get smaller if albedo thresholds relevant to satellite instruments are applied, in particular at high polar latitudes. This implies that weak and moderate NLC is favored when background conditions improve for NLC formation, whereas strong NLC benefits less. Trends of ice cloud parameters are generally smaller in the Southern Hemisphere (SH) compared to the Northern Hemisphere (NH), consistent with observations. Trends in background conditions have counteracting effects on NLC: temperature trends would suggest stronger ice increase in the SH, and water vapor trends would suggest a weaker increase. Larger trends in NLC brightness or occurrence rates are not necessarily associated with larger (more negative) temperature trends. They can also be caused by larger trends of water vapor caused by larger freeze drying, which in turn can be caused by generally lower temperatures and/or more background water. Trends of NLC brightness and occurrence rates decrease with decreasing latitude in both hemispheres. The latitudinal variation of these trends is primarily determined by induced water vapor trends. Trends in NLC altitudes are generally small. Stratospheric temperature trends vary

  19. Asymmetric responses to simulated global warming by populations of Colobanthus quitensis along a latitudinal gradient.

    Science.gov (United States)

    Acuña-Rodríguez, Ian S; Torres-Díaz, Cristian; Hereme, Rasme; Molina-Montenegro, Marco A

    2017-01-01

    The increase in temperature as consequence of the recent global warming has been reported to generate new ice-free areas in the Antarctic continent, facilitating the colonization and spread of plant populations. Consequently, Antarctic vascular plants have been observed extending their southern distribution. But as the environmental conditions toward southern localities become progressively more departed from the species' physiological optimum, the ecophysiological responses and survival to the expected global warming could be reduced. However, if processes of local adaptation are the main cause of the observed southern expansion, those populations could appear constrained to respond positively to the expected global warming. Using individuals from the southern tip of South America, the South Shetland Islands and the Antarctic Peninsula, we assess with a long term experiment (three years) under controlled conditions if the responsiveness of Colobanthus quitensis populations to the expected global warming, is related with their different foliar traits and photoprotective mechanisms along the latitudinal gradient. In addition, we tested if the release of the stress condition by the global warming in these cold environments increases the ecophysiological performance. For this, we describe the latitudinal pattern of net photosynthetic capacity, biomass accumulation, and number of flowers under current and future temperatures respective to each site of origin after three growing seasons. Overall, was found a clinal trend was found in the foliar traits and photoprotective mechanisms in the evaluated C. quitensis populations. On the other hand, an asymmetric response to warming was observed for southern populations in all ecophysiological traits evaluated, suggesting that low temperature is limiting the performance of C. quitensis populations. Our results suggest that under a global warming scenario, plant populations that inhabiting cold zones at high latitudes could

  20. Increased temperatures negatively affect Juniperus communis seeds: evidence from transplant experiments along a latitudinal gradient.

    Science.gov (United States)

    Gruwez, R; De Frenne, P; Vander Mijnsbrugge, K; Vangansbeke, P; Verheyen, K

    2016-05-01

    With a distribution range that covers most of the Northern hemisphere, common juniper (Juniperus communis) has one of the largest ranges of all vascular plant species. In several regions in Europe, however, populations are decreasing in size and number due to failing recruitment. One of the main causes for this failure is low seed viability. Observational evidence suggests that this is partly induced by climate warming, but our mechanistic understanding of this effect remains incomplete. Here, we experimentally assess the influence of temperature on two key developmental phases during sexual reproduction, i.e. gametogenesis and fertilisation (seed phase two, SP2) and embryo development (seed phase three, SP3). Along a latitudinal gradient from southern France to central Sweden, we installed a transplant experiment with shrubs originating from Belgium, a region with unusually low juniper seed viability. Seeds of both seed phases were sampled during three consecutive years, and seed viability assessed. Warming temperatures negatively affected the seed viability of both SP2 and SP3 seeds along the latitudinal gradient. Interestingly, the effect on embryo development (SP3) only occurred in the third year, i.e. when the gametogenesis and fertilisation also took place in warmer conditions. We found strong indications that this negative influence mostly acts via disrupting growth of the pollen tube, the development of the female gametophyte and fertilisation (SP2). This, in turn, can lead to failing embryo development, for example, due to nutritional problems. Our results confirm that climate warming can negatively affect seed viability of juniper. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  1. The objective of this program is to develop innovative DNA detection technologies to achieve fast microbial community assessment. The specific approaches are (1) to develop inexpensive and reliable sequence-proof hybridization DNA detection technology (2) to develop quantitative DNA hybridization technology for microbial community assessment and (3) to study the microbes which have demonstrated the potential to have nuclear waste bioremediation

    International Nuclear Information System (INIS)

    Chen, Chung H.

    2004-01-01

    The objective of this program is to develop innovative DNA detection technologies to achieve fast microbial community assessment. The specific approaches are (1) to develop inexpensive and reliable sequence-proof hybridization DNA detection technology (2) to develop quantitative DNA hybridization technology for microbial community assessment and (3) to study the microbes which have demonstrated the potential to have nuclear waste bioremediation

  2. Galactic cosmic ray gradients, field-aligned and latitudinal, among Voyagers 1/2 and IMP-8

    Science.gov (United States)

    Roelof, E. C.; Decker, R. B.; Krimigis, S. M.; Venkatesan, D.; Lazarus, A. J.

    1982-01-01

    The present investigation represents a summary of a comprehensive analysis of the same subject conducted by Roelof et al. (1981). It is pointed out that the tandem earth-Jupiter trajectories of the Voyager 1/2 spacecraft, combined with baseline measurements from the earth-orbiting IMP 7/8 spacecraft, provide the first opportunity for unambiguously separating latitude from radial or field-aligned effects in galactic cosmic ray gradients. Attention is given to the method of data analysis, and the separation of field-aligned and latitudinal gradients. It is found that latitudinal gradients approximately equal to or greater than 1 percent per deg in the cosmic ray intensity were a common feature of the interplanetary medium between 1 and 5 AU in 1977-78. Except in the most disturbed periods, cosmic ray intensities are well-ordered in field-aligned structures.

  3. Latitudinal distribution of total ozone and NO[sub 2] over the Atlantic Ocean according to measurements in May 1988

    Energy Technology Data Exchange (ETDEWEB)

    Elokhov, A.S; Gruzdev, A.N. (Inst. Fiziki Atmosfery, Moscow (Russian Federation))

    1992-07-01

    Measurements of the total ozone and NO[sub 2] content conducted on board a ship in the 40 deg S - 40 deg N latitudinal belt in the Atlantic Ocean in the second half of May 1988 are reported. The main features of the latitudinal distributions of total ozone and NO[sub 2] are similar. Both distributions have minima in the equatorial zone of the Southern Hemisphere, and both the ozone and NO[sub 2] contents increase from tropical to subtropical latitudes. This increase is the strongest in the subtropical jet stream zone. The fine structure of the studied distributions is also revealed, and its relationship to stratosphere-troposphere exchange processes in the tropopause folding region is discussed. The evening total NO[sub 2] content systematically exceeds that of the morning due to diurnal variations. 20 refs.

  4. Latitudinal variation in nematode diversity and ecological roles along the Chinese coast.

    Science.gov (United States)

    Wu, Jihua; Chen, Huili; Zhang, Youzheng

    2016-11-01

    To test changes in the phylogenetic relatedness, niche breadth, and life-history strategies of nematodes along a latitudinal gradient. Sixteen wetland locations along the Pacific coast of China, from 20°N to 40°N. Linear regression was used to relate nematode phylogenetic relatedness (average taxonomic distinctness (AvTD) and average phylogenetic diversity [AvPD]), life-history group (based on " c - p " colonizer-persister group classification), and dietary specificity (based on guild classification of feeding selectivity) to latitude. Wetland nematode taxonomic diversity (richness and Shannon diversity indices) decreased with increasing latitude along the Chinese coast. Phylogenetic diversity indices (AvTD and AvPD) significantly increased with increasing latitude. This indicates that at lower latitudes, species within the nematode community were more closely related. With increasing latitude, the nematode relative richness and abundance decreased for selective deposit feeders but increased for nonselective deposit feeders. The proportion of general opportunists decreased with increasing latitude, but persisters showed the opposite trend. The annual temperature range and the pH of sediments were more important than vegetation type in structuring nematode communities. Nematode niche breadth was narrower at lower latitudes with respect to dietary specificity. Higher latitudes with a more variable climate favor r over K life-history strategists. Nematode communities at lower latitudes contained more closely related species.

  5. Latitudinal Gradient in Otolith Shape among Local Populations of Atlantic Herring (Clupea harengus L.) in Norway.

    Science.gov (United States)

    Libungan, Lísa Anne; Slotte, Aril; Husebø, Åse; Godiksen, Jane A; Pálsson, Snæbjörn

    2015-01-01

    Otolith shape analysis of Atlantic herring (Clupea harengus) in Norwegian waters shows significant differentiation among fjords and a latitudinal gradient along the coast where neighbouring populations are more similar to each other than to those sampled at larger distances. The otolith shape was obtained using quantitative shape analysis, the outlines were transformed with Wavelet and analysed with multivariate methods. The observed morphological differences are likely to reflect environmental differences but indicate low dispersal among the local herring populations. Otolith shape variation suggests also limited exchange between the local populations and their oceanic counterparts, which could be due to differences in spawning behaviour. Herring from the most northerly location (69°N) in Balsfjord, which is genetically more similar to Pacific herring (Clupea pallasii), differed in otolith shape from all the other populations. Our results suggest that the semi-enclosed systems, where the local populations live and breed, are efficient barriers for dispersal. Otolith shape can thus serve as a marker to identify the origin of herring along the coast of Norway.

  6. Latitudinal amplitude-phase structure of MHD waves: STARE radar observations and modeling

    Directory of Open Access Journals (Sweden)

    Pilipenko V.

    2016-09-01

    Full Text Available We have developed a numerical model that yields a steady-state distribution of field components of MHD wave in an inhomogeneous plasma box simulating the realistic magnetosphere. The problem of adequate boundary condition at the ionosphere–magnetosphere interface for coupled MHD mode is considered. To justify the model’s assumptions, we have derived the explicit inequality showing when the ionospheric inductive Hall effect can be neglected upon the consideration of Alfven wave reflection from the ionospheric boundaries. The model predicts a feature of the ULF spatial amplitude/phase distribution that has not been noticed by the field line resonance theory: the existence of a region with opposite phase delays on the source side of the resonance. This theoretical prediction is supported by the amplitude-phase latitudinal structures of Pc5 waves observed by STARE radar and IMAGE magnetometers. A gradual decrease in azimuthal wave number m at smaller L-shells was observed at longitudinally separated radar beams.

  7. Latitudinal distribution of cesium-137 fallout in 1990 on Saxifraga oppositofolia from Ellesmere Island, Canada

    International Nuclear Information System (INIS)

    France, R.L.; Svoboda, J.; Taylor, H.W.

    1993-01-01

    During the first ski traverse of Ellesmere Island in spring 1990, purple saxifrage (Saxifraga oppositifolia) was collected at 10 sites from 76 to 82 degrees N. Measured 137 Cs levels in this cushion plant displayed a progressive decrease in activity north of 78 degrees, reflecting past global patterns of radionuclide fallout. Lower 137 Cs activity at the southern end of Ellesmere Island may reflect a northward shift of the distribution maximum since a previous latitudinal survey conducted in 1979-1980. Levels of 137 in three species of lichen were consistently higher than those for nearby saxifrage, possibly owing to the larger exposure to fallout for much of the year and the slower rate of lichen growth. In support of previous research, no 134 Cs was detected, which indicated that Chernobyl fallout had not been deposited in significant quantities at these extreme northern latitudes. Specific activities in 1990 of saxifrage samples were compared with similar samples collected during 1979-1980 to derive an effective half-life of 6.2 ± 1.0 years for northern Ellesmere Island

  8. Latitudinal distribution of soft X-ray flares and dispairty in butterfly diagram

    Science.gov (United States)

    Pandey, K. K.; Yellaiah, G.; Hiremath, K. M.

    2015-04-01

    We present statistical analysis of about 63000 soft X-ray flare (class≥C) observed by geostationary operational environmental satellite (GOES) during the period 1976-2008. Class wise occurrence of soft X-ray (SXR) flare is in declining trend since cycle 21. The distribution pattern of cycle 21 shows the transit of hemispheric dominance of flare activity from northern to southern hemisphere and remains there during cycle 22 and 23. During the three cycles, 0-100, 21-300 latitude belts in southern hemisphere (SH) and 31-400 latitude belt in northern hemisphere (NH) are mightier. The 11-200 latitude belt of both hemisphere is mightiest. Correlation coefficient between consecutive latitude appears to be increasing from equator to poleward in northern hemisphere whereas pole to equatorward in southern hemisphere. Slope of the regression line fitted with asymmetry time series of daily flare counts is negative in all three cycles for different classes of flares. The yearly asymmetry curve fitted by a sinusoidal function varies from 5.6 to 11 years period and depends upon the intensity of flare. Variation, of curve fitted with wings of butterfly diagram, from first to second order polynomial suggests that latitudinal migration of flare activity varies from cycle to cycle, northern to southern hemisphere. The variation in slope of the butterfly wing of different flare class indicates the non uniform migration of flare activity.

  9. Paleomagnetism of Cretaceous limestones from western Tarim basin suggests negligible latitudinal offset yet significant clockwise rotation

    Science.gov (United States)

    Tan, X.; Gilder, S.; Chen, Y.; Cogné, J. P.; Courtillot, V. E.; Cai, J.

    2017-12-01

    Large northward translation of central Asian crustal blocks has been reported from paleomagnetism of Cretaceous and Tertiary terrestrial sediments. This motion was initially taken as evidence of deformation occurred in the Asian interior as a result of indentation of the Indian Plate. However, because the amount of motion is far greater than geological observations, accuracy of the paleomagnetic record has become a controversial issue. To solve the problem, it has been shown that the latitudinal offset can be entirely attributed to inclination shallowing during deposition and compaction processes (Tan et al., 2003; Tauxe and Kent, 2004). On the other hand, coeval volcanic rocks from central Asia did record steeper paleomagnetic inclinations than terrestrial rocks (Gilder et al., 2003). To extend the effort of solving the controversy, we report paleomagnetic results of Cretaceous limestones from western Tarim basin. Our results show that the majority of our collections have been overprinted. Fortunately, a special type of limestones preserved stable characteristic remanence. Fold tests suggest a primary origin of the magnetization. Comparison of the paleomagnetic direction with the coeval expected direction from reference poles indicates a negligible amount of northward movement consistent with previous result of inclination correction based on magnetic fabrics, and a pattern of clockwise rotation symmetric with the style observed in the western flank of the Pamir ranges. Rock magnetic data will also be presented to support the accurate paleomagnetic record.

  10. Ross Sea Mollusca from the Latitudinal Gradient Program: R/V Italica 2004 Rauschert dredge samples

    Directory of Open Access Journals (Sweden)

    Claudio Ghiglione

    2013-10-01

    Full Text Available Information regarding the molluscs in this dataset is based on the Rauschert dredge samples collected during the Latitudinal Gradient Program (LGP on board the R/V “Italica” in the Ross Sea (Antarctica in the austral summer 2004. A total of 18 epibenthic dredge deployments/samplings have been performed at four different locations at depths ranging from 84 to 515m by using a Rauschert dredge with a mesh size of 500µm. In total 8,359 specimens have been collected belonging to a total of 161 species. Considering this dataset in terms of occurrences, it corresponds to 505 discrete distributional records (incidence data. Of these, in order of abundance, 5,965 specimens were Gastropoda (accounting for 113 species, 1,323 were Bivalvia (accounting for 36 species, 949 were Aplacophora (accounting for 7 species, 74 specimens were Scaphopoda (3 species, 38 were Monoplacophora (1 species and, finally, 10 specimens were Polyplacophora (1 species. This data set represents the first large-scale survey of benthic micro-molluscs for the area and provides important information about the distribution of several species, which have been seldom or never recorded before in the Ross Sea. All vouchers are permanently stored at the Italian National Antarctic Museum (MNA, Section of Genoa, enabling future comparison and crosschecking. This material is also currently under study, from a molecular point of view, by the barcoding project “BAMBi” (PNRA 2010/A1.10.

  11. Latitudinal variation in avian incubation attentiveness and a test of the food limitation hypothesis

    Science.gov (United States)

    Chalfoun, A.D.; Martin, T.E.

    2007-01-01

    Avian incubation attentiveness has important fitness consequences through its influence on the number and quality of hatched young and energetic costs imposed on parents. Nest attentiveness is highly variable across species and geographical regions. We reviewed the literature and found a worldwide pattern that nest attentiveness of passerines is generally lower in south temperate and tropical regions than in north temperate regions. We also conducted a food manipulation experiment to assess the extent to which nest attentiveness may reflect proximate responses versus an evolved behaviour. We used the karoo prinia, Prinia maculosa, in South Africa, which has very low nest attentiveness (???49%) compared with that of many passerine birds. We provided supplemental food during early incubation to experimental females and compared nest attentiveness and on- and off-bout lengths of experimental and paired control females.??Nest attentiveness of females at food-provisioned nests was significantly higher than that of control females (57% versus 49%). Food-supplemented females also spent significantly less time off the nest than did control females, whereas mean on-bout lengths did not differ. However, mean nest attentiveness of food-provisioned females was still substantially below that of other similar bird species worldwide. Food can be an important proximate influence on parental care behaviour, but proximate influences of food do not explain broad latitudinal patterns of attentiveness. ?? 2007 The Association for the Study of Animal Behaviour.

  12. Global latitudinal species diversity gradient in deep-sea benthic foraminifera

    Science.gov (United States)

    Culver, Stephen J.; Buzas, Martin A.

    2000-02-01

    Global scale patterns of species diversity for modern deep-sea benthic foraminifera, an important component of the bathyal and abyssal meiofauna, are examined using comparable data from five studies in the Atlantic, ranging over 138° of latitude from the Norwegian Sea to the Weddell Sea. We show that a pattern of decreasing diversity with increasing latitude characterises both the North and South Atlantic. This pattern is confirmed for the northern hemisphere by independent data from the west-central North Atlantic and the Arctic basin. Species diversity in the North Atlantic northwards from the equator is variable until a sharp fall in the Norwegian Sea (ca. 65°N). In the South Atlantic species diversity drops from a maximum in latitudes less than 30°S and then decreases slightly from 40 to 70°S. For any given latitude, North Atlantic diversity is generally lower than in the South Atlantic. Both ecological and historical factors related to food supply are invoked to explain the formation and maintenance of the latitudinal gradient of deep-sea benthic foraminiferal species diversity. The gradient formed some 36 million years ago when global climatic cooling led to seasonally fluctuating food supply in higher latitudes.

  13. Latitudinal and longitudinal dependence of the cosmic ray diurnal anisotropy during 2001-2014

    International Nuclear Information System (INIS)

    Tezari, Anastasia; Mavromichalaki, Helen; Katsinis, Dimitrios; Kanellakopoulos, Anastasios; Kolovi, Sofia; Plainaki, Christina; National and Kapodistrian Univ. of Athens; Andriopoulou, Maria

    2016-01-01

    The diurnal anisotropy of cosmic ray intensity for the time period 2001 to 2014 is studied, covering the maximum and the descending phase of solar cycle 23, the minimum between solar cycles 23 and 24, and the ascending phase and maximum of solar cycle 24. Cosmic ray intensity data from 11 neutron monitor stations located at different places around the Northern Hemisphere obtained from the high-resolution Neutron Monitor Database (NMDB) were used. Special software was developed for the calculations of the amplitude and the phase of the diurnal anisotropy vectors on annual and monthly basis using Fourier analysis and for the creation of the harmonic dial diagrams. The geomagnetic bending for each station was taken into account in our calculations determined from the asymptotic cones of each station via the Tsyganenko96 (Tsyganenko and Stern, 1996) magnetospheric model. From our analysis, it was resulted that there is a different behavior of the diurnal anisotropy vectors during the different phases of the solar cycles depending on the solar magnetic field polarity. The latitudinal and longitudinal distribution of the cosmic ray diurnal anisotropy was also examined by grouping the stations according to their geographic coordinates, and it was shown that diurnal variation is modulated not only by the latitude but also by the longitude of the stations. The diurnal anisotropy during strong events of solar and/or cosmic ray activity is discussed.

  14. Latitudinal Gradient in Otolith Shape among Local Populations of Atlantic Herring (Clupea harengus L.) in Norway

    Science.gov (United States)

    Libungan, Lísa Anne; Slotte, Aril; Husebø, Åse; Godiksen, Jane A.; Pálsson, Snæbjörn

    2015-01-01

    Otolith shape analysis of Atlantic herring (Clupea harengus) in Norwegian waters shows significant differentiation among fjords and a latitudinal gradient along the coast where neighbouring populations are more similar to each other than to those sampled at larger distances. The otolith shape was obtained using quantitative shape analysis, the outlines were transformed with Wavelet and analysed with multivariate methods. The observed morphological differences are likely to reflect environmental differences but indicate low dispersal among the local herring populations. Otolith shape variation suggests also limited exchange between the local populations and their oceanic counterparts, which could be due to differences in spawning behaviour. Herring from the most northerly location (69°N) in Balsfjord, which is genetically more similar to Pacific herring (Clupea pallasii), differed in otolith shape from all the other populations. Our results suggest that the semi-enclosed systems, where the local populations live and breed, are efficient barriers for dispersal. Otolith shape can thus serve as a marker to identify the origin of herring along the coast of Norway. PMID:26101885

  15. Latitudinal and longitudinal dependence of the cosmic ray diurnal anisotropy during 2001-2014

    Energy Technology Data Exchange (ETDEWEB)

    Tezari, Anastasia; Mavromichalaki, Helen; Katsinis, Dimitrios; Kanellakopoulos, Anastasios; Kolovi, Sofia [National and Kapodistrian Univ. of Athens (Greece). Nuclear and Particle Physics Dept.; Plainaki, Christina [INAF-IAPS, Rome (Italy); National and Kapodistrian Univ. of Athens (Greece). Nuclear and Particle Physics Dept.; Andriopoulou, Maria [Austrian Academy of Sciences, Graz (Austria). Space Research Inst.

    2016-07-01

    The diurnal anisotropy of cosmic ray intensity for the time period 2001 to 2014 is studied, covering the maximum and the descending phase of solar cycle 23, the minimum between solar cycles 23 and 24, and the ascending phase and maximum of solar cycle 24. Cosmic ray intensity data from 11 neutron monitor stations located at different places around the Northern Hemisphere obtained from the high-resolution Neutron Monitor Database (NMDB) were used. Special software was developed for the calculations of the amplitude and the phase of the diurnal anisotropy vectors on annual and monthly basis using Fourier analysis and for the creation of the harmonic dial diagrams. The geomagnetic bending for each station was taken into account in our calculations determined from the asymptotic cones of each station via the Tsyganenko96 (Tsyganenko and Stern, 1996) magnetospheric model. From our analysis, it was resulted that there is a different behavior of the diurnal anisotropy vectors during the different phases of the solar cycles depending on the solar magnetic field polarity. The latitudinal and longitudinal distribution of the cosmic ray diurnal anisotropy was also examined by grouping the stations according to their geographic coordinates, and it was shown that diurnal variation is modulated not only by the latitude but also by the longitude of the stations. The diurnal anisotropy during strong events of solar and/or cosmic ray activity is discussed.

  16. Intra-Specific Latitudinal Clines in Leaf Carbon, Nitrogen, and Phosphorus and their Underlying Abiotic Correlates in Ruellia Nudiflora

    OpenAIRE

    Abdala-Roberts, Luis; Covelo, Felisa; Parra-Tabla, Víctor; Terán, Jorge C. Berny Mier y; Mooney, Kailen A.; Moreira, Xoaquín

    2018-01-01

    While plant intra-specific variation in the stoichiometry of nutrients and carbon is well documented, clines for such traits have been less studied, despite their potential to reveal the mechanisms underlying such variation. Here we analyze latitudinal variation in the concentration of leaf nitrogen (N), phosphorus (P), carbon (C) and their ratios across 30 populations of the perennial herb Ruellia nudiflora. In addition, we further determined whether climatic and soil variables underlie any ...

  17. Evolution of avian clutch size along latitudinal gradients: do seasonality, nest predation or breeding season length matter?

    Science.gov (United States)

    Griebeler, E M; Caprano, T; Böhning-Gaese, K

    2010-05-01

    Birds display a latitudinal gradient in clutch size with smaller clutches in the tropics and larger in the temperate region. Three factors have been proposed to affect this pattern: seasonality of resources (SR), nest predation and length of the breeding season (LBS). Here, we test the importance of these factors by modelling clutch size evolution within bird populations under different environmental settings. We use an individual-based ecogenetic simulation model that combines principles from population ecology and life history theory. Results suggest that increasing SR from the tropics to the poles by itself or in combination with a decreasing predation rate and LBS can generate the latitudinal gradient in clutch size. Annual fecundity increases and annual adult survival rate decreases from the tropics to the poles. We further show that the annual number of breeding attempts that (together with clutch size) determines total annual egg production is an important trait to understand latitudinal patterns in these life history characteristics. Field experiments that manipulate environmental factors have to record effects not only on clutch size, but also on annual number of breeding attempts. We use our model to predict the outcome of such experiments under different environmental settings.

  18. Regional and latitudinal patterns of soft-bottom macrobenthic invertebrates along French coasts: Results from the RESOMAR database

    Science.gov (United States)

    Gallon, Régis K.; Lavesque, Nicolas; Grall, Jacques; Labrune, Céline; Gremare, Antoine; Bachelet, Guy; Blanchet, Hugues; Bonifácio, Paulo; Bouchet, Vincent M. P.; Dauvin, Jean-Claude; Desroy, Nicolas; Gentil, Franck; Guerin, Laurent; Houbin, Céline; Jourde, Jérôme; Laurand, Sandrine; Le Duff, Michel; Le Garrec, Vincent; de Montaudouin, Xavier; Olivier, Frédéric; Orvain, Francis; Sauriau, Pierre-Guy; Thiebaut, Éric; Gauthier, Olivier

    2017-12-01

    This study aims to describe the patterns of soft bottom macrozoobenthic richness along French coasts. It is based on a collaborative database developed by the "Réseau des Stations et Observatoires Marins" (RESOMAR). We investigated patterns of species richness in sublittoral soft bottom habitats (EUNIS level 3) at two different spatial scales: 1) seaboards: English Channel, Bay of Biscay and Mediterranean Sea and 2) 0.5° latitudinal and longitudinal grid. Total observed richness, rarefaction curves and three incidence-based richness estimators (Chao2, ICE and Jacknife1) were used to compare soft bottom habitats species richness in each seaboard. Overall, the Mediterranean Sea has the highest richness and despite higher sampling effort, the English Channel hosts the lowest number of species. The distribution of species occurrence within and between seaboards was assessed for each major phylum using constrained rarefaction curves. The Mediterranean Sea hosts the highest number of exclusive species. In pairwise comparisons, it also shares a lower proportion of taxa with the Bay of Biscay (34.1%) or the English Channel (27.6%) than that shared between these two seaboards (49.7%). Latitudinal species richness patterns along the Atlantic and English Channel coasts were investigated for each major phylum using partial LOESS regression controlling for sampling effort. This showed the existence of a bell-shaped latitudinal pattern, highlighting Brittany as a hotspot for macrobenthic richness at the confluence of two biogeographic provinces.

  19. Mean annual precipitation explains spatiotemporal patterns of Cenozoic mammal beta diversity and latitudinal diversity gradients in North America.

    Directory of Open Access Journals (Sweden)

    Danielle Fraser

    Full Text Available Spatial diversity patterns are thought to be driven by climate-mediated processes. However, temporal patterns of community composition remain poorly studied. We provide two complementary analyses of North American mammal diversity, using (i a paleontological dataset (2077 localities with 2493 taxon occurrences spanning 21 discrete subdivisions of the Cenozoic based on North American Land Mammal Ages (36 Ma--present, and (ii climate space model predictions for 744 extant mammals under eight scenarios of future climate change. Spatial variation in fossil mammal community structure (β diversity is highest at intermediate values of continental mean annual precipitation (MAP estimated from paleosols (∼ 450 mm/year and declines under both wetter and drier conditions, reflecting diversity patterns of modern mammals. Latitudinal gradients in community change (latitudinal turnover gradients, aka LTGs increase in strength through the Cenozoic, but also show a cyclical pattern that is significantly explained by MAP. In general, LTGs are weakest when continental MAP is highest, similar to modern tropical ecosystems in which latitudinal diversity gradients are weak or undetectable. Projections under modeled climate change show no substantial change in β diversity or LTG strength for North American mammals. Our results suggest that similar climate-mediated mechanisms might drive spatial and temporal patterns of community composition in both fossil and extant mammals. We also provide empirical evidence that the ecological processes on which climate space models are based are insufficient for accurately forecasting long-term mammalian response to anthropogenic climate change and inclusion of historical parameters may be essential.

  20. TPA device for demonstration

    International Nuclear Information System (INIS)

    1980-02-01

    The TPA (torus plasma for amature) is a small race-trac type device made by the technical service division to demonstrate basic properties of plasma such as electron temperature, conductivity, effect of helical field for toroidal drift, and shape of plasma in mirror and cusp magnetic field in linear section. The plasmas are produced by RF discharge (-500W) and/or DC discharge (-30 mA) within glass discharge tube. Where major radius is 50 cm, length of linear section is 50 cm, toroidal magnetic field is 200 gauss. The device has been designed to be compact with only 100 V power source (-3.2 KW for the case without helical field) and to be full automatic sequence of operation. (author)

  1. Variation in size and growth of the great scallop Pecten maximus along a latitudinal gradient.

    Directory of Open Access Journals (Sweden)

    Laurent Chauvaud

    Full Text Available Understanding the relationship between growth and temperature will aid in the evaluation of thermal stress and threats to ectotherms in the context of anticipated climate changes. Most Pecten maximus scallops living at high latitudes in the northern hemisphere have a larger maximum body size than individuals further south, a common pattern among many ectotherms. We investigated differences in daily shell growth among scallop populations along the Northeast Atlantic coast from Spain to Norway. This study design allowed us to address precisely whether the asymptotic size observed along a latitudinal gradient, mainly defined by a temperature gradient, results from differences in annual or daily growth rates, or a difference in the length of the growing season. We found that low annual growth rates in northern populations are not due to low daily growth values, but to the smaller number of days available each year to achieve growth compared to the south. We documented a decrease in the annual number of growth days with age regardless of latitude. However, despite initially lower annual growth performances in terms of growing season length and growth rate, differences in asymptotic size as a function of latitude resulted from persistent annual growth performances in the north and sharp declines in the south. Our measurements of daily growth rates throughout life in a long-lived ectothermic species provide new insight into spatio-temporal variations in growth dynamics and growing season length that cannot be accounted for by classical growth models that only address asymptotic size and annual growth rate.

  2. Latitudinal diversity gradients in New World bats: are they a consequence of niche conservatism?

    Science.gov (United States)

    Ramos Pereira, Maria João; Palmeirim, Jorge M

    2013-01-01

    The increase in species diversity from the Poles to the Equator is a major biogeographic pattern, but the mechanisms underlying it remain obscure. Our aim is to contribute to their clarification by describing the latitudinal gradients in species richness and in evolutionary age of species of New World bats, and testing if those patterns may be explained by the niche conservatism hypothesis. Maps of species ranges were used to estimate species richness in a 100 x 100 km grid. Root distances in a molecular phylogeny were used as a proxy for the age of species, and the mean root distance of the species in each cell of the grid was estimated. Generalised additive models were used to relate latitude with both species richness and mean root distance. This was done for each of the three most specious bat families and for all Chiroptera combined. Species richness increases towards the Equator in the whole of the Chiroptera and in the Phyllostomidae and Molossidae, families that radiated in the tropics, but the opposite trend is observed in the Vespertilionidae, which has a presumed temperate origin. In the whole of the Chiroptera, and in the three main families, there were more basal species in the higher latitudes, and more derived species in tropical areas. In general, our results were not consistent with the predictions of niche conservatism. Tropical niche conservatism seems to keep bat clades of tropical origin from colonizing temperate zones, as they lack adaptations to survive cold winters, such as the capacity to hibernate. However, the lower diversity of Vespertilionidae in the Neotropics is better explained by competition with a diverse pre-existing community of bats than by niche conservatism.

  3. Toward Spectroscopically Detecting the Global Latitudinal Temperature Variation on the Solar Surface

    Science.gov (United States)

    Takeda, Y.; UeNo, S.

    2017-09-01

    A very slight rotation-induced latitudinal temperature variation (presumably on the order of several kelvin) on the solar surface is theoretically expected. While recent high-precision solar brightness observations reported its detection, confirmation by an alternative approach using the strengths of spectral lines is desirable, for which reducing the noise due to random fluctuation caused by atmospheric inhomogeneity is critical. Toward this difficult task, we carried out a pilot study of spectroscopically investigating the relative variation of temperature (T) at a number of points in the solar circumference region near to the limb (where latitude dependence should be detectable, if any exists) based on the equivalent widths (W) of 28 selected lines in the 5367 - 5393 Å and 6075 - 6100 Å regions. We paid special attention to i) clarifying which types of lines should be employed and ii) how much precision is attainable in practice. We found that lines with strong T-sensitivity (|log W/log T|) should be used and that very weak lines should be avoided because they inevitably suffer strong relative fluctuations (Δ W/W). Our analysis revealed that a precision of Δ T/T ≈ 0.003 (corresponding to ≈ 15 K) can be achieved at best by a spectral line with comparatively large |log W/log T|, although this can possibly be further improved When a number of lines are used all together. Accordingly, if many such favorable lines could be measured with subpercent precision of Δ W/W and by averaging the resulting Δ T/T from each line, the random noise would eventually be reduced to ≲ 1 K and detection of a very subtle amount of global T-gradient might be possible.

  4. Local and latitudinal variation in abundance: the mechanisms shaping the distribution of an ecosystem engineer.

    Science.gov (United States)

    Crutsinger, Gregory M; Gonzalez, Angélica L; Crawford, Kerri M; Sanders, Nathan J

    2013-01-01

    Ecological processes that determine the abundance of species within ecological communities vary across space and time. These scale-dependent processes are especially important when they affect key members of a community, such as ecosystem engineers that create shelter and food resources for other species. Yet, few studies have examined the suite of processes that shape the abundance of ecosystem engineers. Here, we evaluated the relative influence of temporal variation, local processes, and latitude on the abundance of an engineering insect-a rosette-galling midge, Rhopalomyia solidaginis (Diptera: Cecidomyiidae). Over a period of 3-5 years, we studied the density and size of galls across a suite of local experiments that manipulated genetic variation, soil nutrient availability, and the removal of other insects from the host plant, Solidago altissima (tall goldenrod). We also surveyed gall density within a single growing season across a 2,300 km latitudinal transect of goldenrod populations in the eastern United States. At the local scale, we found that host-plant genotypic variation was the best predictor of rosette gall density and size within a single year. We found that the removal of other insect herbivores resulted in an increase in gall density and size. The amendment of soil nutrients for four years had no effect on gall density, but galls were smaller in carbon-added plots compared to control and nitrogen additions. Finally, we observed that gall density varied several fold across years. At the biogeographic scale, we observed that the density of rosette gallers peaked at mid-latitudes. Using meta-analytic approaches, we found that the effect size of time, followed by host-plant genetic variation and latitude were the best predictors of gall density. Taken together, our study provides a unique comparison of multiple factors across different spatial and temporal scales that govern engineering insect herbivore density.

  5. Photosynthetic performance in Sphagnum transplanted along a latitudinal nitrogen deposition gradient.

    Science.gov (United States)

    Granath, Gustaf; Strengbom, Joachim; Breeuwer, Angela; Heijmans, Monique M P D; Berendse, Frank; Rydin, Håkan

    2009-04-01

    Increased N deposition in Europe has affected mire ecosystems. However, knowledge on the physiological responses is poor. We measured photosynthetic responses to increasing N deposition in two peatmoss species (Sphagnum balticum and Sphagnum fuscum) from a 3-year, north-south transplant experiment in northern Europe, covering a latitudinal N deposition gradient ranging from 0.28 g N m(-2) year(-1) in the north, to 1.49 g N m(-2) year(-1) in the south. The maximum photosynthetic rate (NP(max)) increased southwards, and was mainly explained by tissue N concentration, secondly by allocation of N to the photosynthesis, and to a lesser degree by modified photosystem II activity (variable fluorescence/maximum fluorescence yield). Although climatic factors may have contributed, these results were most likely attributable to an increase in N deposition southwards. For S. fuscum, photosynthetic rate continued to increase up to a deposition level of 1.49 g N m(-2) year(-1), but for S. balticum it seemed to level out at 1.14 g N m(-2) year(-1). The results for S. balticum suggested that transplants from different origin (with low or intermediate N deposition) respond differently to high N deposition. This indicates that Sphagnum species may be able to adapt or physiologically adjust to high N deposition. Our results also suggest that S. balticum might be more sensitive to N deposition than S. fuscum. Surprisingly, NP(max) was not (S. balticum), or only weakly (S. fuscum) correlated with biomass production, indicating that production is to a great extent is governed by factors other than the photosynthetic capacity.

  6. Latitudinal distribution of the Jovian plasma sheet ions observed by Juno JADE-I

    Science.gov (United States)

    Kim, T. K. H.; Valek, P. W.; McComas, D. J.; Allegrini, F.; Bagenal, F.; Bolton, S. J.; Connerney, J. E. P.; Ebert, R. W.; Levin, S.; Louarn, P.; Pollock, C. J.; Ranquist, D. A.; Szalay, J.; Thomsen, M. F.; Wilson, R. J.

    2017-12-01

    The Jovian plasma sheet is a region where the centrifugal force dominates the heavy ion plasma. Properties of the plasma sheet ions near the equatorial plane have been studied with in-situ measurements from the Pioneer, Voyager, and Galileo spacecraft. However, the ion properties for the off-equator regions are not well known due to the limited measurements. Juno is the first polar orbiting spacecraft that can investigate the high latitude region of the Jovian magnetosphere. With Juno's unique trajectory, we will investigate the latitudinal distribution of the Jovian plasma sheet ions using measurements from the Jovian Auroral Distributions Experiment Ion sensor (JADE-I). JADE-I measures an ion's energy-per-charge (E/Q) from 0.01 keV/q to 46.2 keV/q with an electrostatic analyzer (ESA) and a mass-per-charge (M/Q) up to 64 amu/q with a carbon-foil-based time-of-flight (TOF) mass spectrometer. We have shown that the ambiguity between and (both have M/Q of 16) can be resolved in JADE-I using a semi-empirical simulation tool based on carbon foil effects (i.e., charge state modification, angular scattering, and energy loss) from incident ions passing through the TOF mass spectrometer. Based on the simulation results, we have developed an Ion Composition Analysis Tool (ICAT) that determines ion composition at each energy step of JADE-I (total of 64 steps). The velocity distribution for each ion species can be obtained from the ion composition as a function of each energy step. Since there is an ambipolar electric field due to mobile electrons and equatorially confined heavy ions, we expect to see acceleration along the field line. This study will show the species separated velocity distribution at various latitudes to investigate how the plasma sheet ions evolve along the field line.

  7. Equatorial F-region plasma depletion drifts: latitudinal and seasonal variations

    Directory of Open Access Journals (Sweden)

    A. A. Pimenta

    2003-12-01

    Full Text Available The equatorial ionospheric irregularities have been observed in the past few years by different techniques (e.g. ground-based radar, digisonde, GPS, optical instruments, in situ satellite and rocket instrumentation, and its time evolution and propagation characteristics can be used to study important aspects of ionospheric dynamics and thermosphere-ionosphere coupling. At present, one of the most powerful optical techniques to study the large-scale ionospheric irregularities is the all-sky imaging photometer system, which normally measures the strong F-region nightglow 630 nm emission from atomic oxygen. The monochromatic OI 630 nm emission images usually show quasi-north-south magnetic field-aligned intensity depletion bands, which are the bottomside optical signatures of large-scale F-region plasma irregularities (also called plasma bubbles. The zonal drift velocities of the plasma bubbles can be inferred from the space-time displacement of the dark structures (low intensity regions seen on the images. In this study, images obtained with an all-sky imaging photometer, using the OI 630 nm nightglow emission, from Cachoeira Paulista (22.7° S, 45° W, 15.8° S dip latitude, Brazil, have been used to determine the nocturnal monthly and latitudinal variation characteristics of the zonal plasma bubble drift velocities in the low latitude (16.7° S to 28.7° S region. The east and west walls of the plasma bubble show a different evolution with time. The method used here is based on the western wall of the bubble, which presents a more stable behavior. Also, the observed zonal plasma bubble drift velocities are compared with the thermospheric zonal neutral wind velocities obtained from the HWM-90 model (Hedin et al., 1991 to investigate the thermosphere-ionosphere coupling. Salient features from this study are presented and discussed.Key words. Ionosphere (ionosphere-atmosphere interactions; ionospheric irregularities; instruments and techniques

  8. On the utilization of ionosonde data to analyze the latitudinal penetration of ionospheric storm effects

    International Nuclear Information System (INIS)

    Forbes, J.M.; Codrescu, M.; Hall, T.J.

    1988-01-01

    Upper atmosphere science is placing increased emphasis on global coupling between the magnetosphere, ionosphere, and thermosphere systems, particularly with regard to the penetration of dynamic, chemical, and electrodynamic effects from high to low latitudes during magnetically disturbed periods. An emerging potential exists for latitudinal and longitudinal chains of ionosondes to contribute uniquely to this thrust in ways complementary to the capabilities and shortcomings of other groundbased sensors and satellites. Here we illustrate a methodology whereby the fullest potential of such ionosonde data can be realized. Data from a chain of stations close to the -165 0 magnetic meridian and separated by about 5 0 in magnetic latitude are used to study the relationships between magnetic activity, hmF2, foF2, and inferred meridional winds during 17--28 April, 1979. Hourly values are fit in latitude using Legendre polynomials, and variations from quiet-time values are displayed in latitude-U.T. coordinates using a color graphics method which provides an illuminating illustration of the penetration of ionospheric disturbances in latitude and their dependence on Kp, storm time, and local time. Observed effects are interpreted in terms of plausible electric field, neutral wind, and neutral composition changes during the storm period. For instance, net depletions in foF2 occur over the entire disturbed interval down to about 25 0 --30 0 latitude, apparently due to such increased N 2 densities that the resulting enhanced plasma loss rates overcompensate and ''positive'' storm effects whereby southward winds elevate the F-layer peak to altitudes of reduced chemical loss

  9. Susceptibility to a metal under global warming is shaped by thermal adaptation along a latitudinal gradient.

    Science.gov (United States)

    Dinh Van, Khuong; Janssens, Lizanne; Debecker, Sara; De Jonge, Maarten; Lambret, Philippe; Nilsson-Örtman, Viktor; Bervoets, Lieven; Stoks, Robby

    2013-09-01

    Global warming and contamination represent two major threats to biodiversity that have the potential to interact synergistically. There is the potential for gradual local thermal adaptation and dispersal to higher latitudes to mitigate the susceptibility of organisms to contaminants and global warming at high latitudes. Here, we applied a space-for-time substitution approach to study the thermal dependence of the susceptibility of Ischnura elegans damselfly larvae to zinc in a common garden warming experiment (20 and 24 °C) with replicated populations from three latitudes spanning >1500 km in Europe. We observed a striking latitude-specific effect of temperature on the zinc-induced mortality pattern; local thermal adaptation along the latitudinal gradient made Swedish, but not French, damselfly larvae more susceptible to zinc at 24 °C. Latitude- and temperature-specific differences in zinc susceptibility may be related to the amount of energy available to defend against and repair damage since Swedish larvae showed a much stronger zinc-induced reduction of food intake at 24 °C. The pattern of local thermal adaptation indicates that the predicted temperature increase of 4 °C by 2100 will strongly magnify the impact of a contaminant such as zinc at higher latitudes unless there is thermal evolution and/or migration of lower latitude genotypes. Our results underscore the critical importance of studying the susceptibility to contaminants under realistic warming scenarios taking into account local thermal adaptation across natural temperature gradients. © 2013 John Wiley & Sons Ltd.

  10. A continuous latitudinal energy balance model to explore non-uniform climate engineering strategies

    Science.gov (United States)

    Bonetti, F.; McInnes, C. R.

    2016-12-01

    Current concentrations of atmospheric CO2 exceed measured historical levels in modern times, largely attributed to anthropogenic forcing since the industrial revolution. The required decline in emissions rates has never been achieved leading to recent interest in climate engineering for future risk-mitigation strategies. Climate engineering aims to offset human-driven climate change. It involves techniques developed both to reduce the concentration of CO2 in the atmosphere (Carbon Dioxide Removal (CDR) methods) and to counteract the radiative forcing that it generates (Solar Radiation Management (SRM) methods). In order to investigate effects of SRM technologies for climate engineering, an analytical model describing the main dynamics of the Earth's climate has been developed. The model is a time-dependent Energy Balance Model (EBM) with latitudinal resolution and allows for the evaluation of non-uniform climate engineering strategies. A significant disadvantage of climate engineering techniques involving the management of solar radiation is regional disparities in cooling. This model offers an analytical approach to design multi-objective strategies that counteract climate change on a regional basis: for example, to cool the Artic and restrict undesired impacts at mid-latitudes, or to control the equator-to-pole temperature gradient. Using the Green's function approach the resulting partial differential equation allows for the computation of the surface temperature as a function of time and latitude when a 1% per year increase in the CO2 concentration is considered. After the validation of the model through comparisons with high fidelity numerical models, it will be used to explore strategies for the injection of the aerosol precursors in the stratosphere. In particular, the model involves detailed description of the optical properties of the particles, the wash-out dynamics and the estimation of the radiative cooling they can generate.

  11. Genetic structure and bio-climatic modeling support allopatric over parapatric speciation along a latitudinal gradient

    Directory of Open Access Journals (Sweden)

    Rossetto Maurizio

    2012-08-01

    Full Text Available Abstract Background Four of the five species of Telopea (Proteaceae are distributed in a latitudinal replacement pattern on the south-eastern Australian mainland. In similar circumstances, a simple allopatric speciation model that identifies the origins of genetic isolation within temporal geographic separation is considered as the default model. However, secondary contact between differentiated lineages can result in similar distributional patterns to those arising from a process of parapatric speciation (where gene flow between lineages remains uninterrupted during differentiation. Our aim was to use the characteristic distributional patterns in Telopea to test whether it reflected the evolutionary models of allopatric or parapatric speciation. Using a combination of genetic evidence and environmental niche modelling, we focused on three main questions: do currently described geographic borders coincide with genetic and environmental boundaries; are there hybrid zones in areas of secondary contact between closely related species; did species distributions contract during the last glacial maximum resulting in distributional gaps even where overlap and hybridisation currently occur? Results Total genomic DNA was extracted from 619 individuals sampled from 36 populations representing the four species. Seven nuclear microsatellites (nSSR and six chloroplast microsatellites (cpSSR were amplified across all populations. Genetic structure and the signature of admixture in overlap zones was described using the Bayesian clustering methods implemented in STUCTURE and NewHybrids respectively. Relationships between chlorotypes were reconstructed as a median-joining network. Environmental niche models were produced for all species using environmental parameters from both the present day and the last glacial maximum (LGM. The nSSR loci amplified a total of 154 alleles, while data for the cpSSR loci produced a network of six chlorotypes. STRUCTURE revealed

  12. Genetic structure and bio-climatic modeling support allopatric over parapatric speciation along a latitudinal gradient.

    Science.gov (United States)

    Rossetto, Maurizio; Allen, Chris B; Thurlby, Katie A G; Weston, Peter H; Milner, Melita L

    2012-08-20

    Four of the five species of Telopea (Proteaceae) are distributed in a latitudinal replacement pattern on the south-eastern Australian mainland. In similar circumstances, a simple allopatric speciation model that identifies the origins of genetic isolation within temporal geographic separation is considered as the default model. However, secondary contact between differentiated lineages can result in similar distributional patterns to those arising from a process of parapatric speciation (where gene flow between lineages remains uninterrupted during differentiation). Our aim was to use the characteristic distributional patterns in Telopea to test whether it reflected the evolutionary models of allopatric or parapatric speciation. Using a combination of genetic evidence and environmental niche modelling, we focused on three main questions: do currently described geographic borders coincide with genetic and environmental boundaries; are there hybrid zones in areas of secondary contact between closely related species; did species distributions contract during the last glacial maximum resulting in distributional gaps even where overlap and hybridisation currently occur? Total genomic DNA was extracted from 619 individuals sampled from 36 populations representing the four species. Seven nuclear microsatellites (nSSR) and six chloroplast microsatellites (cpSSR) were amplified across all populations. Genetic structure and the signature of admixture in overlap zones was described using the Bayesian clustering methods implemented in STUCTURE and NewHybrids respectively. Relationships between chlorotypes were reconstructed as a median-joining network. Environmental niche models were produced for all species using environmental parameters from both the present day and the last glacial maximum (LGM).The nSSR loci amplified a total of 154 alleles, while data for the cpSSR loci produced a network of six chlorotypes. STRUCTURE revealed an optimum number of five clusters

  13. Equatorial F-region plasma depletion drifts: latitudinal and seasonal variations

    Directory of Open Access Journals (Sweden)

    A. A. Pimenta

    Full Text Available The equatorial ionospheric irregularities have been observed in the past few years by different techniques (e.g. ground-based radar, digisonde, GPS, optical instruments, in situ satellite and rocket instrumentation, and its time evolution and propagation characteristics can be used to study important aspects of ionospheric dynamics and thermosphere-ionosphere coupling. At present, one of the most powerful optical techniques to study the large-scale ionospheric irregularities is the all-sky imaging photometer system, which normally measures the strong F-region nightglow 630 nm emission from atomic oxygen. The monochromatic OI 630 nm emission images usually show quasi-north-south magnetic field-aligned intensity depletion bands, which are the bottomside optical signatures of large-scale F-region plasma irregularities (also called plasma bubbles. The zonal drift velocities of the plasma bubbles can be inferred from the space-time displacement of the dark structures (low intensity regions seen on the images. In this study, images obtained with an all-sky imaging photometer, using the OI 630 nm nightglow emission, from Cachoeira Paulista (22.7° S, 45° W, 15.8° S dip latitude, Brazil, have been used to determine the nocturnal monthly and latitudinal variation characteristics of the zonal plasma bubble drift velocities in the low latitude (16.7° S to 28.7° S region. The east and west walls of the plasma bubble show a different evolution with time. The method used here is based on the western wall of the bubble, which presents a more stable behavior. Also, the observed zonal plasma bubble drift velocities are compared with the thermospheric zonal neutral wind velocities obtained from the HWM-90 model (Hedin et al., 1991 to investigate the thermosphere-ionosphere coupling. Salient features from this study are presented

  14. Fire Regime along Latitudinal Gradients of Continuous to Discontinuous Coniferous Boreal Forests in Eastern Canada

    Directory of Open Access Journals (Sweden)

    Jeanne Portier

    2016-09-01

    Full Text Available Fire is the main disturbance in North American coniferous boreal forests. In Northern Quebec, Canada, where forest management is not allowed, the landscape is gradually constituted of more opened lichen woodlands. Those forests are discontinuous and show a low regeneration potential resulting from the cumulative effects of harsh climatic conditions and very short fire intervals. In a climate change context, and because the forest industry is interested in opening new territories to forest management in the north, it is crucial to better understand how and why fire risk varies from the north to the south at the transition between the discontinuous and continuous boreal forest. We used time-since-fire (TSF data from fire archives as well as a broad field campaign in Quebec’s coniferous boreal forests along four north-south transects in order to reconstruct the fire history of the past 150 to 300 years. We performed survival analyses in each transect in order to (1 determine if climate influences the fire risk along the latitudinal gradient; (2 fractionate the transects into different fire risk zones; and (3 quantify the fire cycle—defined as the time required to burn an area equivalent to the size of the study area—of each zone and compare its estimated value with current fire activity. Results suggest that drought conditions are moderately to highly responsible for the increasing fire risk from south to north in the three westernmost transects. No climate influence was observed in the last one, possibly because of its complex physical environment. Fire cycles are shortening from south to north, and from east to west. Limits between high and low fire risk zones are consistent with the limit between discontinuous and continuous forests, established based on recent fire activity. Compared to the last 40 years, fire cycles of the last 150–300 years are shorter. Our results suggest that as drought episodes are expected to become more frequent

  15. Annual and latitudinal variations of surface fluxes and meteorological variables at Arctic terrestrial sites

    Science.gov (United States)

    Grachev, Andrey; Uttal, Taneil; Persson, Ola; Konopleva-Akish, Elena; Crepinsek, Sara; Cox, Christopher; Fairall, Christopher; Makshtas, Alexander; Repina, Irina

    2016-04-01

    This study analyzes and discusses seasonal and latitudinal variations of surface fluxes (turbulent, radiative, and soil ground heat) and other ancillary surface/snow/permafrost data based on in-situ measurements made at two long-term research observatories near the coast of the Arctic Ocean located in Canada and Russia. The hourly averaged data collected at Eureka (Canadian territory of Nunavut) and Tiksi (East Siberia) located at two quite different latitudes (80.0 N and 71.6 N respectively) are analyzed in details to describe the seasons in the Arctic. Although Eureka and Tiksi are located at the different continents and at the different latitudes, the annual course of the surface meteorology and the surface fluxes are qualitatively very similar. The air and soil temperatures display the familiar strong seasonal trend with maximum of measured temperatures in mid-summer and minimum during winter. According to our data, variation in incoming short-wave solar radiation led the seasonal pattern of the air and soil temperatures, and the turbulent fluxes. During the dark Polar nights, air and ground temperatures are strongly controlled by long-wave radiation associated generally with cloud cover. Due to the fact that in average the higher latitudes receive less solar radiation than lower latitudes, a length of the convective atmospheric boundary layer (warm season) is shorter and middle-summer amplitude of the turbulent fluxes is generally less in Eureka than in Tiksi. However, since solar elevation angle at local midnight in the middle of Arctic summer is higher for Eureka as compared to Tiksi, stable stratification and upward turbulent flux for carbon dioxide is generally did not observed at Eureka site during summer seasons. It was found a high correlation between the turbulent fluxes of sensible and latent heat, carbon dioxide and the net solar radiation. A comprehensive evaluation of energy balance closure problem is performed based on the multi-year data sets

  16. Diversidade de abelhas (Hymenoptera, Apidae) ao longo de um gradiente latitudinal na Mata Atlântica

    OpenAIRE

    Gonçalves,Rodrigo Barbosa; Brandão,Carlos Roberto Ferreira

    2008-01-01

    A Mata Atlântica é um dos ambientes mais ricos e ameaçados do mundo, o que deveria ter estimulado em muito o estudo e a conservação do Bioma, mas a fauna de Hymenoptera permanece ainda relativamente pouco conhecida. Em especial, a fauna de abelhas da floresta ombrófila densa é pouco estudada em comparação à fauna das áreas abertas brasileiras. O projeto temático "Biodiversidade de Hymenoptera e Isoptera: riqueza e diversidade ao longo de um gradiente latitudinal na Mata Atlântica - a floresta...

  17. Caught in the act: Incipient speciation across a latitudinal gradient in a semifossorial mammal from Madagascar, the mole tenrec Oryzorictes hova (Tenrecidae).

    Science.gov (United States)

    Everson, Kathryn M; Hildebrandt, Kyndall B P; Goodman, Steven M; Olson, Link E

    2018-02-28

    Madagascar is one of the world's foremost biodiversity hotspots, yet a large portion of its flora and fauna remains undescribed and the driving forces of in situ diversification are not well understood. Recent studies have identified a widespread, latitudinally structured phylogeographic pattern in Madagascar's humid-forest mammals, amphibians, reptiles, and insects. Several factors may be driving this pattern, namely biogeographic barriers (i.e., rivers or valleys) or past episodes of forest contraction and expansion. In this study, we describe the phylogeographic structure of the small, semifossorial mammal Oryzorictes hova, one of Madagascar's two species of mole tenrec, found throughout Madagascar's eastern humid forest belt, from high-elevation montane forest to low-elevation forests, as well as disturbed habitat such as rice fields. Using one mitochondrial locus, four nuclear loci, and 31 craniomandibular measurements, we identified three distinct populations of O. hova associated with the northern, central, and southern regions of the island. We found little evidence of gene flow among these populations, so we treated each population as a potential species. We validated species limits using two Bayesian methods: BP&P, employing only DNA sequence data, and iBPP using both DNA and morphological data, and we assessed whether these methods are susceptible to producing false positive errors. Molecular and morphological data support the recognition of each of the three populations of O. hova as distinct species, but formal species descriptions will require additional data from type specimens. This study illustrates the importance of using integrative datasets, multiple methodological approaches, and extensive geographic sampling for species delimitation and adds evidence for a widespread phylogeographic pattern in Madagascar's humid forest taxa. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Vertebrate Herbivore Browsing on Neighboring Forage Species Increases the Growth and Dominance of Siberian Alder Across a Latitudinal Transect in Northern Alaska.

    Science.gov (United States)

    McNeill, E. M.; Ruess, R. W.

    2017-12-01

    Vertebrate herbivores strongly influence plant growth and architecture, biogeochemical cycling, and successional dynamics in boreal and arctic ecosystems. One of the most notable impacts of vertebrate herbivory is on the growth and spread of alder, a chemically-defended, N-fixing shrub whose distribution in the Alaskan arctic has expanded dramatically over the past 60 years. Although herbivore effects on thin-leaf alder are well described for interior Alaskan floodplains, no work has been conducted on the effects of herbivores on Siberian alder (Alnus viridis spp fruticosa), despite the increasing importance of this species to high latitude ecosystems. We characterized browsing by snowshoe hares, moose, and willow ptarmigan on dominant shrub species across topo-edaphic sequences within 5 ecoregions along a 600 km latitudinal transect extending from interior Alaska to the North Slope. Ptarmigan browsed wind-blown lowland and alpine sites devoid of trees in all regions; moose browsed predominantly willow species in hardwood and mixed forests and were absent north of the Brooks Range; snowshoe hares selected habitats and forage based on their local density and vulnerability to predators. Browsing intensity on Siberian alder was either undetectable or low, limited primarily to hare browsing on young ramets in the northern boreal forest where hare density relative to forage availability is highest. Overall, alder height growth was positively correlated with levels of herbivory on competing shrub species. Our data support the hypothesis that vertebrate herbivore browsing is indirectly augmenting the growth, dominance, and possible spread of Siberian alder throughout its northern Alaskan range. Given the potential high rates of N-fixation inputs by Siberian alder, we believe herbivores are also having strong indirect effects on biogeochemical cycling and possibly C storage in these landscapes.

  19. Sequence assembly

    DEFF Research Database (Denmark)

    Scheibye-Alsing, Karsten; Hoffmann, S.; Frankel, Annett Maria

    2009-01-01

    Despite the rapidly increasing number of sequenced and re-sequenced genomes, many issues regarding the computational assembly of large-scale sequencing data have remain unresolved. Computational assembly is crucial in large genome projects as well for the evolving high-throughput technologies and...... in genomic DNA, highly expressed genes and alternative transcripts in EST sequences. We summarize existing comparisons of different assemblers and provide a detailed descriptions and directions for download of assembly programs at: http://genome.ku.dk/resources/assembly/methods.html....

  20. Genome Sequencing

    DEFF Research Database (Denmark)

    Sato, Shusei; Andersen, Stig Uggerhøj

    2014-01-01

    The current Lotus japonicus reference genome sequence is based on a hybrid assembly of Sanger TAC/BAC, Sanger shotgun and Illumina shotgun sequencing data generated from the Miyakojima-MG20 accession. It covers nearly all expressed L. japonicus genes and has been annotated mainly based on transcr......The current Lotus japonicus reference genome sequence is based on a hybrid assembly of Sanger TAC/BAC, Sanger shotgun and Illumina shotgun sequencing data generated from the Miyakojima-MG20 accession. It covers nearly all expressed L. japonicus genes and has been annotated mainly based...

  1. [Variability of vegetation growth season in different latitudinal zones of North China: a monitoring by NOAA NDVI and MSAVI].

    Science.gov (United States)

    Wang, Hong; Li, Xiaobing; Han, Ruibo; Ge, Yongqin

    2006-12-01

    In this study, North China was latitudinally divided into five zones, i.e., 32 degrees - 36 degrees N (Zone I), 36 degrees - 40 degrees N (Zone II), 40 degrees - 44 degrees N (Zone III), 44 degrees - 48 degrees N (Zone IV) and 48 degrees - 52 degrees N (Zone V), and the NOAA/ AVHRR NDVI and MSAVI time-series images from 1982 to 1999 were smoothed with Savitzky-Golay filter algorithm. Based on the EOF analysis, the principal components of NDVI and MSAVI for the vegetations in different latitudinal zones of North China were extracted, the annual beginning and ending dates and the length of growth season in 1982 - 1999 were estimated, and the related parameters were linearly fitted, aimed to analyze the variability of vegetation growth season. The results showed that the beginning date of the growth season in different zones tended to be advanced, while the ending date tended to be postponed with increasing latitude. The length of the growth season was also prolonged, with the prolonging time exceeded 10 days.

  2. Galactic cosmic ray gradients, field-aligned and latitudinal, among Voyagers 1/2 and IMP-8

    International Nuclear Information System (INIS)

    Roelof, E.C.; Decker, R.B.; Krimigis, S.M.; Venkatesan, D.; Lazarus, A.J.

    1982-01-01

    The tandem Earth-Jupiter trajectories of the Voyager 1/2 spacecraft, combined with baseline measurements from the earth-orbiting IMP-7/8 spacecraft, provide the first opportunity for unambiguously separating latitude from radial or field-aligned effects in galactic cosmic ray gradients. Anti-coincidence solid-state detectors on the Voyager 1/2 LECP experiment measure nucleons > or approximately 20 MeV/nuc with large (28 cm 2 ) omnidirectional geometry factors. Anti-coincidence scintillators on the IMP-7/8 CPME with omnidirectional geometry factors comparable to those on Voyager measure nucleons > or approximately 35 MeV/nuc. Because the Voyagers are well-connected via the interplanetary magnetic field (IMF) to the near-Earth vicinity throughout their transit from 1-5 AU (September 1977 - February 1979), we obtained the first direct measurement of field-aligned gradients, i.e., those that do not depend upon ''corotation'' from one spacecraft to another over many days. Another new result is the unambiguous identification of nonuniform latitudinal gradients approximately 2-5% degree -1 in structures lasting 10-30 days. There is additional evidence for somewhat smaller latitudinal gradients, north to south and probably mixed with small field-aligned gradients -1 , which persist for several solar rotations

  3. Latitudinal distribution of zooplankton communities in the Western Pacific along 160°E during summer 2014

    Science.gov (United States)

    Sun, Dong; Wang, Chunsheng

    2017-05-01

    A total of 51 mesozooplankton samples collected with a WP2 net from 0 to 200 m depth along 160°E (4°S-46°N) in the Western Pacific from June to July 2014 were analyzed. The latitudinal distribution of mesozooplankton community structure was analyzed. The average biomass and abundance in different provinces generally increased with latitude: the biomass of zooplankton ranged from 1.18 mg DW m- 3 (11°N) to 97.81 mg DW m- 3 (45°N), and the abundance of zooplankton ranged from 45.11 ind. m- 3 (3°S) to 439.84 ind. m- 3 (41°N). The community structure of zooplankton also showed a significant latitudinal variation. At lower latitudes, calanoid copepods were the most abundant group, while cyclopoid copepods were the most abundant group at higher latitudes. Multidimensional scaling analysis of community structure and other physical/chemical/biological characteristics supported five ecological provinces in the northwestern Pacific: the Western Pacific Warm Pool Province (WARM), the North Pacific Tropical Gyre (NPTG), the North Pacific Subtropical Gyre (NPST), the Kuroshio Current Province (KURO) and the Pacific Subarctic Gyres Province (PSAG). The Kuroshio Current Province can be regarded as a transitional zone between the subarctic and northern subtropical area, and this transitional zone corresponds much more closely to the ecocline concept, rather than the ecotone concept.

  4. Temperature and diet effects on omnivorous fish performance: Implications for the latitudinal diversity gradient in herbivorous fishes

    Science.gov (United States)

    Behrens, M.D.; Lafferty, K.D.

    2007-01-01

    Herbivorous fishes show a clear latitudinal diversity gradient, making up a larger proportion of the fish species in a community in tropical waters than in temperate waters. One proposed mechanism that could drive this gradient is a physiological constraint due to temperature. One prediction based on this mechanism is that if herbivorous fishes could shift their diet to animal material, they would be better able to grow, survive, and reproduce in cold waters. We tested this prediction on the omnivore Girella nigricans under different temperature and diet regimes using RNA-DNA ratios as an indicator of performance. Fish had increased performance (100%) at low temperatures (12??C) when their diet was supplemented with animal material. In contrast, at higher temperatures (17, 22, and 27??C) fish showed no differences between diets. This indicates that omnivorous fishes could increase their performance at low temperatures by consuming more animal matter. This study supports the hypothesis that a relative increase in the nutritional value of plant material at warmer temperatures could drive the latitudinal diversity gradient in herbivorous fishes. ?? 2007 NRC.

  5. Seasonal and latitudinal variations of surface fluxes at two Arctic terrestrial sites

    Science.gov (United States)

    Grachev, Andrey A.; Persson, P. Ola G.; Uttal, Taneil; Akish, Elena A.; Cox, Christopher J.; Morris, Sara M.; Fairall, Christopher W.; Stone, Robert S.; Lesins, Glen; Makshtas, Alexander P.; Repina, Irina A.

    2017-11-01

    This observational study compares seasonal variations of surface fluxes (turbulent, radiative, and soil heat) and other ancillary atmospheric/surface/permafrost data based on in-situ measurements made at terrestrial research observatories located near the coast of the Arctic Ocean. Hourly-averaged multiyear data sets collected at Eureka (Nunavut, Canada) and Tiksi (East Siberia, Russia) are analyzed in more detail to elucidate similarities and differences in the seasonal cycles at these two Arctic stations, which are situated at significantly different latitudes (80.0°N and 71.6°N, respectively). While significant gross similarities exist in the annual cycles of various meteorological parameters and fluxes, the differences in latitude, local topography, cloud cover, snowfall, and soil characteristics produce noticeable differences in fluxes and in the structures of the atmospheric boundary layer and upper soil temperature profiles. An important factor is that even though higher latitude sites (in this case Eureka) generally receive less annual incoming solar radiation but more total daily incoming solar radiation throughout the summer months than lower latitude sites (in this case Tiksi). This leads to a counter-intuitive state where the average active layer (or thaw line) is deeper and the topsoil temperature in midsummer are higher in Eureka which is located almost 10° north of Tiksi. The study further highlights the differences in the seasonal and latitudinal variations of the incoming shortwave and net radiation as well as the moderating cloudiness effects that lead to temporal and spatial differences in the structure of the atmospheric boundary layer and the uppermost ground layer. Specifically the warm season (Arctic summer) is shorter and mid-summer amplitude of the surface fluxes near solar noon is generally less in Eureka than in Tiksi. During the dark Polar night and cold seasons (Arctic winter) when the ground is covered with snow and air temperatures

  6. Woody plant encroachment effect on soil organic carbon dynamics: results from a latitudinal gradient in Italy

    Science.gov (United States)

    Pellis, Guido; Chiti, Tommaso; Moscatelli, Maria Cristina; Marinari, Sara; Papale, Dario

    2016-04-01

    Woody plant encroachment into pastures and grasslands represents a significant land cover change phenomenon, with a considerable impact on carbon dynamics at an ecosystem level. It was estimated that 7.64% of the Southern Europe land was subject to that process between 1950 to 2010. As a result of woody encroachment, changes in vegetation composition can produce substantial changes to the soil organic carbon (SOC) cycle. Despite the numerous papers published on land-use change, an evaluation of the IPCC terrestrial carbon pools changes occurring during woody encroachment on abandoned pastures and grasslands is still lacking, particularly for the Italian territory. Therefore, the aim of this study was to investigate the role of woody encroachment on carbon sequestration over abandoned pastures and grasslands in Alpine and Apennine ecosystems, with a particular focus on the SOC. We applied a chronosequence approach to seven selected sites located along a latitudinal gradient in Italy. Each chronosequence consisted of a pasture currently managed, three sites abandoned at different times in the past and, finally, a mature forest stand representing the last phase of the succession. The European Commission sampling protocols to certify SOC changes was adopted to estimate the variations following woody encroachment. Soil samples were collected at different depths in the topsoil (0-30 cm) and subsoil (30-70 cm), despite the original protocol formulation being limited to the topsoil only. In addition, aboveground living biomass (AGB), dead wood and litter were also measured following international protocols. Considering all C pools together, woody plant encroachment leads to a progressive C stock accumulation in all the chronosequences. The total C stock of mature forest stands ranges from 1.78±0.11 times (Eastern Alps) to 2.48±0.31 times (central Apennine) the initial value on pastures. Unsurprisingly, the C stocks of AGB, dead wood and litter all increase during the

  7. Gradiente latitudinal de riqueza de espécies de formigas em cerrado: regra de Rapoport e efeitos da produtividade e heterogeneidade

    OpenAIRE

    Ribas, Carla Rodrigues

    2006-01-01

    O gradiente latitudinal de riqueza de espécies (GLRE) é um padrão bem documentado para diversos grupos de organismos. Apesar de várias hipóteses terem sido levantadas para explicar o gradiente algumas são tidas como mais promissoras, tais como as relacionadas à energia, a heterogeneidade ambiental, ao tempo evolutivo e ao efeito do domínio mediano. O objetivo dessa tese é testar a existência do gradiente latitudinal de riqueza de espécies de formigas arborícolas em cerrado, assim como testar ...

  8. Latitudinal variation in the symbiotic dinoflagellateSymbiodiniumof the common reef zoantharianPalythoa tuberculosaon the Saudi Arabian coast of the Red Sea

    KAUST Repository

    Reimer, James D.

    2016-08-08

    Aim The Red Sea presents an ideal setting to explore the variability of Symbiodinium over environmental, latitudinal and geographical gradients. We used sequences from two molecular markers to examine genetic diversity of Symbiodinium associated with the widely distributed zoantharian Palythoa tuberculosa in the northern and central Red Sea. Location Northern and central Red Sea. Methods Specimens (n = 329) were collected from 15 locations. Sequence data from nuclear ribosomal ITS2 (n = 269) and chloroplast minicircle psbAncr (n = 173) were phylogenetically analysed (maximum likelihood, neighbour joining), and Symbiodinium types identified for each P. tuberculosa colony. To establish whether environment was a strong predictor of Symbiodinium psbAncr lineage, SST, chlorophyll-a, salinity, and depth data were fit into a multinomial logistic regression using the package VGAM in the R statistical environment. Results Based on ITS2 and psbAncr results, P. tuberculosa colonies were shown to be in symbioses with Symbiodinium clade C (n = 172) and clade D (n = 1). Within clade C, four psbAncr lineages were observed; closely related lineages designated Pt-1-a and Pt-1-b, and closely related lineages Pt-3-a and Pt-3-b. By location, Pt-1-a dominated the sites within the Gulf of Aqaba (c. 86%, 37/43 colonies). At the entrance to the Gulf of Aqaba, Pt-3-a dominated (c. 88%, 15/17), while the more southern remaining sites in the Red Sea were dominated by Pt-3-b (c. 78%, 89/113). Main conclusions Multinomial logistic regression analyses established that predictions based on the combination of temperature, chlorophyll-a and salinity accurately reflected symbiont distributions in the central and northern Red Sea. Palythoa tuberculosa host Pt-1-a in the coldest region, the Gulf of Aqaba (annual average SST = 24.5–25.0 °C), while immediately to the south Pt-3-a dominates (SST = 26.0–26.5 °C), with warmest southern sites dominated by Pt-3-b (SST > 26.5 °C). The Gulf of Aqaba is

  9. Latitudinal exposure to DDTs, HCB, PCBs, PBDEs and DP in giant petrels (Macronectes spp.) across the Southern Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Roscales, Jose L., E-mail: jlroscales@iqog.csic.es [Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC (IQOG-CSIC), Juan de la Cierva 3, 28006 Madrid (Spain); González-Solís, Jacob; Zango, Laura [Institut de Recerca de la Biodiversitat (IRBio) and Department of Animal Biology, Universitat de Barcelona, Av Diagonal 643, 08028 Barcelona (Spain); Ryan, Peter G. [Percy FitzPatrick Institute, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch 7701 (South Africa); Jiménez, Begoña [Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC (IQOG-CSIC), Juan de la Cierva 3, 28006 Madrid (Spain)

    2016-07-15

    Studies on Persistent Organic Pollutants (POPs) in Antarctic wildlife are scarce, and usually limited to a single locality. As a result, wildlife exposure to POPs across the Southern Ocean is poorly understood. In this study, we report the differential exposure of the major southern ocean scavengers, the giant petrels, to POPs across a wide latitudinal gradient. Selected POPs (PCBs, HCB, DDTs, PBDEs) and related compounds, such as Dechlorane Plus (DP), were analyzed in plasma of southern giant petrels (Macronectes giganteus) breeding on Livingston (62°S 61°W, Antarctica), Marion (46°S 37°E, sub-Antarctic), and Gough (40°S 10°W, cool temperate) islands. Northern giant petrels (Macronectes halli) from Marion Island were also studied. Stable isotope ratios of C and N (δ{sup 13}C and δ{sup 15}N) were used as dietary tracers of the marine habitat and trophic level, respectively. Breeding locality was a major factor explaining petrel exposure to POPs compared with species and sex. Significant relationships between δ{sup 13}C values and POP burdens, at both inter- and intra-population levels, support latitudinal variations in feeding grounds as a key factor in explaining petrel pollutant burdens. Overall, pollutant levels in giant petrels decreased significantly with latitude, but the relative abundance (%) of the more volatile POPs increased towards Antarctica. DP was found at negligible levels compared with legacy POPs in Antarctic seabirds. Spatial POP patterns found in giant petrels match those predicted by global distribution models, and reinforce the hypothesis of atmospheric long-range transport as the main source of POPs in Antarctica. Our results confirm that wildlife movements out of the polar region markedly increase their exposure to POPs. Therefore, strategies for Antarctic wildlife conservation should consider spatial heterogeneity in exposure to marine pollution. Of particular relevance is the need to clarify the exposure of Antarctic predators to

  10. Adaptations to "Thermal Time" Constraints in Papilio: Latitudinal and Local Size Clines Differ in Response to Regional Climate Change.

    Science.gov (United States)

    Scriber, J Mark; Elliot, Ben; Maher, Emily; McGuire, Molly; Niblack, Marjie

    2014-01-21

    Adaptations to "thermal time" (=Degree-day) constraints on developmental rates and voltinism for North American tiger swallowtail butterflies involve most life stages, and at higher latitudes include: smaller pupae/adults; larger eggs; oviposition on most nutritious larval host plants; earlier spring adult emergences; faster larval growth and shorter molting durations at lower temperatures. Here we report on forewing sizes through 30 years for both the northern univoltine P. canadensis (with obligate diapause) from the Great Lakes historical hybrid zone northward to central Alaska (65° N latitude), and the multivoltine, P. glaucus from this hybrid zone southward to central Florida (27° N latitude). Despite recent climate warming, no increases in mean forewing lengths of P. glaucus were observed at any major collection location (FL to MI) from the 1980s to 2013 across this long latitudinal transect (which reflects the "converse of Bergmann's size Rule", with smaller females at higher latitudes). Unlike lower latitudes, the Alaska, Ontonogon, and Chippewa/Mackinac locations (for P. canadensis) showed no significant increases in D-day accumulations, which could explain lack of size change in these northernmost locations. As a result of 3-4 decades of empirical data from major collection sites across these latitudinal clines of North America, a general "voltinism/size/D-day" model is presented, which more closely predicts female size based on D-day accumulations, than does latitude. However, local "climatic cold pockets" in northern Michigan and Wisconsin historically appeared to exert especially strong size constraints on female forewing lengths, but forewing lengths quickly increased with local summer warming during the recent decade, especially near the warming edges of the cold pockets. Results of fine-scale analyses of these "cold pockets" are in contrast to non-significant changes for other Papilio populations seen across the latitudinal transect for P. glaucus

  11. Spatial and Temporal Growth Variation of Pinus heldreichii Christ. Growing along a Latitudinal Gradient in Kosovo and Albania

    Directory of Open Access Journals (Sweden)

    Faruk Bojaxhi

    2017-01-01

    Full Text Available Background and Purpose: Trees growing at high elevations are particularly sensitive to climate variability. In this study, tree-ring chronologies of Pinus heldreichii Christ. have been developed to examine their dynamism along a 350 km latitudinal gradient. Materials and Methods: Sampling was conducted in 6 high elevation sites along a latitudinal gradient from Kosovo and Albania. Two opposite cores from 148 healthy and dominant P. heldreichii trees were taken using an increment borer. The cores were mounted and sanded, and after a rigorous cross-dating, the ring widths were measured to a resolution of 0.01 mm using the LINTAB 6 measuring device. The ARSTAN program was used for tree-ring series detrending and site chronologies’ development. The relationship between radial growth and climate, as well as between temporal patterns of P. heldreichii growth were investigated using simple correlation analysis and principal component analysis (PCA over the common period 1951-2013. Results: Radial growth variability of Bosnian pine increased with latitude and elevation. Significant correlations among our chronologies and others from neighbouring countries indicated that our chronologies possess a good regional climatic signal. P. heldreichii growth at all sampling sites was significantly influenced by seasonal and mean annual temperatures, as well as by the July drought. Thus, temperature was the main driving force of species growth, showing a larger control at spatial scale than precipitation. The difference in species growth patterns along the latitudinal gradient is implicated by the common action of climatic and non-climatic factors (age and human activity. With continued warming and precipitation decrease during the second half of the 20th century, P. heldreichii growth from these high elevation sites resulted in being more sensitive to drought. This climatic signal is assumed to be stronger in the future due to climate change. Conclusions: P

  12. Sap-feeding insects on forest trees along latitudinal gradients in northern Europe: a climate-driven patterns.

    Science.gov (United States)

    Kozlov, Mikhail V; Stekolshchikov, Andrey V; Söderman, Guy; Labina, Eugenia S; Zverev, Vitali; Zvereva, Elena L

    2015-01-01

    Knowledge of the latitudinal patterns in biotic interactions, and especially in herbivory, is crucial for understanding the mechanisms that govern ecosystem functioning and for predicting their responses to climate change. We used sap-feeding insects as a model group to test the hypotheses that the strength of plant-herbivore interactions in boreal forests decreases with latitude and that this latitudinal pattern is driven primarily by midsummer temperatures. We used a replicated sampling design and quantitatively collected and identified all sap-feeding insects from four species of forest trees along five latitudinal gradients (750-1300 km in length, ten sites in each gradient) in northern Europe (59 to 70°N and 10 to 60°E) during 2008-2011. Similar decreases in diversity of sap-feeding insects with latitude were observed in all gradients during all study years. The sap-feeder load (i.e. insect biomass per unit of foliar biomass) decreased with latitude in typical summers, but increased in an exceptionally hot summer and was independent of latitude during a warm summer. Analysis of combined data from all sites and years revealed dome-shaped relationships between the loads of sap-feeders and midsummer temperatures, peaking at 17 °C in Picea abies, at 19.5 °C in Pinus sylvestris and Betula pubescens and at 22 °C in B. pendula. From these relationships, we predict that the losses of forest trees to sap-feeders will increase by 0-45% of the current level in southern boreal forests and by 65-210% in subarctic forests with a 1 °C increase in summer temperatures. The observed relationships between temperatures and the loads of sap-feeders differ between the coniferous and deciduous tree species. We conclude that climate warming will not only increase plant losses to sap-feeding insects, especially in subarctic forests, but can also alter plant-plant interactions, thereby affecting both the productivity and the structure of future forest ecosystems. © 2014

  13. Latitudinal distribution of the solar wind properties in the low- and high-pressure regimes: Wind observations

    Directory of Open Access Journals (Sweden)

    C. Lacombe

    Full Text Available The solar wind properties depend on λ, the heliomagnetic latitude with respect to the heliospheric current sheet (HCS, more than on the heliographic latitude. We analyse the wind properties observed by Wind at 1 AU during about 2.5 solar rotations in 1995, a period close to the last minimum of solar activity. To determine λ, we use a model of the HCS which we fit to the magnetic sector boundary crossings observed by Wind. We find that the solar wind properties mainly depend on the modulus |λ|. But they also depend on a local parameter, the total pressure (magnetic pressure plus electron and proton thermal pressure. Furthermore, whatever the total pressure, we observe that the plasma properties also depend on the time: the latitudinal gradients of the wind speed and of the proton temperature are not the same before and after the closest HCS crossing. This is a consequence of the dynamical stream interactions. In the low pressure wind, at low |λ|, we find a clear maximum of the density, a clear minimum of the wind speed and of the proton temperature, a weak minimum of the average magnetic field strength, a weak maximum of the average thermal pressure, and a weak maximum of the average β factor. This overdense sheet is embedded in a density halo. The latitudinal thickness is about 5° for the overdense sheet, and 20° for the density halo. The HCS is thus wrapped in an overdense sheet surrounded by a halo, even in the non-compressed solar wind. In the high-pressure wind, the plasma properties are less well ordered as functions of the latitude than in the low-pressure wind; the minimum of the average speed is seen before the HCS crossing. The latitudinal thickness of the high-pressure region is about 20°. Our observations are qualitatively consistent with the numerical model of Pizzo for the deformation of the heliospheric current sheet and plasma sheet.

    Key words: Interplanetary physics (solar wind

  14. Latitudinal exposure to DDTs, HCB, PCBs, PBDEs and DP in giant petrels (Macronectes spp.) across the Southern Ocean

    International Nuclear Information System (INIS)

    Roscales, Jose L.; González-Solís, Jacob; Zango, Laura; Ryan, Peter G.; Jiménez, Begoña

    2016-01-01

    Studies on Persistent Organic Pollutants (POPs) in Antarctic wildlife are scarce, and usually limited to a single locality. As a result, wildlife exposure to POPs across the Southern Ocean is poorly understood. In this study, we report the differential exposure of the major southern ocean scavengers, the giant petrels, to POPs across a wide latitudinal gradient. Selected POPs (PCBs, HCB, DDTs, PBDEs) and related compounds, such as Dechlorane Plus (DP), were analyzed in plasma of southern giant petrels (Macronectes giganteus) breeding on Livingston (62°S 61°W, Antarctica), Marion (46°S 37°E, sub-Antarctic), and Gough (40°S 10°W, cool temperate) islands. Northern giant petrels (Macronectes halli) from Marion Island were also studied. Stable isotope ratios of C and N (δ 13 C and δ 15 N) were used as dietary tracers of the marine habitat and trophic level, respectively. Breeding locality was a major factor explaining petrel exposure to POPs compared with species and sex. Significant relationships between δ 13 C values and POP burdens, at both inter- and intra-population levels, support latitudinal variations in feeding grounds as a key factor in explaining petrel pollutant burdens. Overall, pollutant levels in giant petrels decreased significantly with latitude, but the relative abundance (%) of the more volatile POPs increased towards Antarctica. DP was found at negligible levels compared with legacy POPs in Antarctic seabirds. Spatial POP patterns found in giant petrels match those predicted by global distribution models, and reinforce the hypothesis of atmospheric long-range transport as the main source of POPs in Antarctica. Our results confirm that wildlife movements out of the polar region markedly increase their exposure to POPs. Therefore, strategies for Antarctic wildlife conservation should consider spatial heterogeneity in exposure to marine pollution. Of particular relevance is the need to clarify the exposure of Antarctic predators to emerging

  15. Transformed composite sequences for improved qubit addressing

    Science.gov (United States)

    Merrill, J. True; Doret, S. Charles; Vittorini, Grahame; Addison, J. P.; Brown, Kenneth R.

    2014-10-01

    Selective laser addressing of a single atom or atomic ion qubit can be improved using narrow-band composite pulse sequences. We describe a Lie-algebraic technique to generalize known narrow-band sequences and introduce sequences related by dilation and rotation of sequence generators. Our method improves known narrow-band sequences by decreasing both the pulse time and the residual error. Finally, we experimentally demonstrate these composite sequences using 40Ca+ ions trapped in a surface-electrode ion trap.

  16. Insect temperature-body size trends common to laboratory, latitudinal and seasonal gradients are not found across altitudes

    DEFF Research Database (Denmark)

    Horne, Curtis R.; Hirst, Andrew G.; Atkinson, David

    2018-01-01

    Body size affects rates of most biological and ecological processes, from individual performance to ecosystem function, and is fundamentally linked to organism fitness. Within species, size at maturity can vary systematically with environmental temperature in the laboratory and across seasons...... altitude. Although the general direction of body size clines along altitudinal gradients has been examined previously, to our knowledge altitude-body size (A-S) clines have never been synthesised quantitatively, nor compared with temperature-size (T-S) responses measured under controlled laboratory......, as well as over latitudinal gradients. Recent meta-analyses have revealed a close match in the magnitude and direction of these size gradients in various arthropod orders, suggesting that these size responses share common drivers. As with increasing latitude, temperature also decreases with increasing...

  17. Environmental plasticity of Pinot noir grapevine leaves: A trans-European study of morphological and biochemical changes along a 1,500-km latitudinal climatic gradient.

    Science.gov (United States)

    Castagna, Antonella; Csepregi, Kristóf; Neugart, Susanne; Zipoli, Gaetano; Večeřová, Kristýna; Jakab, Gábor; Jug, Tjaša; Llorens, Laura; Martínez-Abaigar, Javier; Martínez-Lüscher, Johann; Núñez-Olivera, Encarnación; Ranieri, Annamaria; Schoedl-Hummel, Katharina; Schreiner, Monika; Teszlák, Péter; Tittmann, Susanne; Urban, Otmar; Verdaguer, Dolors; Jansen, Marcel A K; Hideg, Éva

    2017-11-01

    A 2-year study explored metabolic and phenotypic plasticity of sun-acclimated Vitis vinifera cv. Pinot noir leaves collected from 12 locations across a 36.69-49.98°N latitudinal gradient. Leaf morphological and biochemical parameters were analysed in the context of meteorological parameters and the latitudinal gradient. We found that leaf fresh weight and area were negatively correlated with both global and ultraviolet (UV) radiation, cumulated global radiation being a stronger correlator. Cumulative UV radiation (sumUVR) was the strongest correlator with most leaf metabolites and pigments. Leaf UV-absorbing pigments, total antioxidant capacities, and phenolic compounds increased with increasing sumUVR, whereas total carotenoids and xanthophylls decreased. Despite of this reallocation of metabolic resources from carotenoids to phenolics, an increase in xanthophyll-cycle pigments (the sum of the amounts of three xanthophylls: violaxanthin, antheraxanthin, and zeaxanthin) with increasing sumUVR indicates active, dynamic protection for the photosynthetic apparatus. In addition, increased amounts of flavonoids (quercetin glycosides) and constitutive β-carotene and α-tocopherol pools provide antioxidant protection against reactive oxygen species. However, rather than a continuum of plant acclimation responses, principal component analysis indicates clusters of metabolic states across the explored 1,500-km-long latitudinal gradient. This study emphasizes the physiological component of plant responses to latitudinal gradients and reveals the physiological plasticity that may act to complement genetic adaptations. © 2017 John Wiley & Sons Ltd.

  18. Latitudinal extent of the January 2005 solar proton event in the Northern Hemisphere from satellite observations of hydroxyl

    Directory of Open Access Journals (Sweden)

    P. T. Verronen

    2007-11-01

    Full Text Available We utilise hydroxyl observations from the MLS/Aura satellite instrument to study the latitudinal extent of particle forcing in the northern polar region during the January 2005 solar proton event. MLS is the first satellite instrument to observe HOx changes during such an event. We also predict the hydroxyl changes with respect to the magnetic latitude by the Sodankylä Ion and Neutral Chemistry model, estimating the variable magnetic cutoff energies for protons using a parameterisation based on magnetosphere modelling and the planetary magnetic index Kp. In the middle and lower mesosphere, HOx species are good indicators of the changes in the atmosphere during solar proton events, because they respond rapidly to both increases and decreases in proton forcing. Also, atmospheric transport has a negligible effect on HOx because of its short chemical lifetime. The observations indicate the boundary of the proton forcing and a transition region, from none to the "full" effect, which ranges from about 57 to 64 degrees of magnetic latitude. When saturating the rigidity cutoff Kp at 6 in the model, as suggested by earlier studies using observations of cosmic radio noise absorption, the equatorward boundary of the transition region is offset by ≈2 degrees polewards compared with the data, thus the latitudinal extent of the proton forcing in the atmosphere is underestimated. However, the model predictions are in reasonable agreement with the MLS measurements when the Kp index is allowed to vary within its nominal range, i.e., from 1 to 9 in the cutoff calculation.

  19. A genetically-based latitudinal cline in the emission of herbivore-induced plant volatile organic compounds.

    Science.gov (United States)

    Wason, Elizabeth L; Agrawal, Anurag A; Hunter, Mark D

    2013-08-01

    The existence of predictable latitudinal variation in plant defense against herbivores remains controversial. A prevailing view holds that higher levels of plant defense evolve at low latitudes compared to high latitudes as an adaptive plant response to higher herbivore pressure on low-latitude plants. To date, this prediction has not been examined with respect to volatile organic compounds (VOCs) that many plants emit, often thus attracting the natural enemies of herbivores. Here, we compared genetically-based constitutive and herbivore-induced aboveground vegetative VOC emissions from plants originating across a gradient of more than 10° of latitude (>1,500 km). We collected headspace VOCs from Asclepias syriaca (common milkweed) originating from 20 populations across its natural range and grown in a common garden near the range center. Feeding by specialist Danaus plexippus (monarch) larvae induced VOCs, and field environmental conditions (temperature, light, and humidity) also influenced emissions. Monarch damage increased plant VOC concentrations and altered VOC blends. We found that genetically-based induced VOC emissions varied with the latitude of plant population origin, although the pattern followed the reverse of that predicted-induced VOC concentration increased with increasing latitude. This pattern appeared to be driven by a greater induction of sesquiterpenoids at higher latitudes. In contrast, constitutive VOC emission did not vary systematically with latitude, and the induction of green leafy volatiles declined with latitude. Our results do not support the prevailing view that plant defense is greater at lower than at higher latitudes. That the pattern holds only for herbivore-induced VOC emission, and not constitutive emission, suggests that latitudinal variation in VOCs is not a simple adaptive response to climatic factors.

  20. The geography of fear: a latitudinal gradient in anti-predator escape distances of birds across Europe.

    Directory of Open Access Journals (Sweden)

    Mario Díaz

    Full Text Available All animals flee from potential predators, and the distance at which this happens is optimized so the benefits from staying are balanced against the costs of flight. Because predator diversity and abundance decreases with increasing latitude, and differs between rural and urban areas, we should expect escape distance when a predator approached the individual to decrease with latitude and depend on urbanization. We measured the distance at which individual birds fled (flight initiation distance, FID, which represents a reliable and previously validated surrogate measure of response to predation risk following a standardized protocol in nine pairs of rural and urban sites along a ca. 3000 km gradient from Southern Spain to Northern Finland during the breeding seasons 2009-2010. Raptor abundance was estimated by means of standard point counts at the same sites where FID information was recorded. Data on body mass and phylogenetic relationships among bird species sampled were extracted from the literature. An analysis of 12,495 flight distances of 714 populations of 159 species showed that mean FID decreased with increasing latitude after accounting for body size and phylogenetic effects. This decrease was paralleled by a similar cline in an index of the abundance of raptors. Urban populations had consistently shorter FIDs, supporting previous findings. The difference between rural and urban habitats decreased with increasing latitude, also paralleling raptor abundance trends. Overall, the latitudinal gradient in bird fear was explained by raptor abundance gradients, with additional small effects of latitude and intermediate effects of habitat. This study provides the first empirical documentation of a latitudinal trend in anti-predator behavior, which correlated positively with a similar trend in the abundance of predators.

  1. Quantum-Sequencing: Fast electronic single DNA molecule sequencing

    Science.gov (United States)

    Casamada Ribot, Josep; Chatterjee, Anushree; Nagpal, Prashant

    2014-03-01

    A major goal of third-generation sequencing technologies is to develop a fast, reliable, enzyme-free, high-throughput and cost-effective, single-molecule sequencing method. Here, we present the first demonstration of unique ``electronic fingerprint'' of all nucleotides (A, G, T, C), with single-molecule DNA sequencing, using Quantum-tunneling Sequencing (Q-Seq) at room temperature. We show that the electronic state of the nucleobases shift depending on the pH, with most distinct states identified at acidic pH. We also demonstrate identification of single nucleotide modifications (methylation here). Using these unique electronic fingerprints (or tunneling data), we report a partial sequence of beta lactamase (bla) gene, which encodes resistance to beta-lactam antibiotics, with over 95% success rate. These results highlight the potential of Q-Seq as a robust technique for next-generation sequencing.

  2. Biodiesel Mass Transit Demonstration

    Science.gov (United States)

    2010-04-01

    The Biodiesel Mass Transit Demonstration report is intended for mass transit decision makers and fleet managers considering biodiesel use. This is the final report for the demonstration project implemented by the National Biodiesel Board under a gran...

  3. Authoring Effective Demonstrations

    National Research Council Canada - National Science Library

    Fu, Dan; Jensen, Randy; Salas, Eduardo; Rosen, Michael A; Ramachandran, Sowmya; Upshaw, Christin L; Hinkelman, Elizabeth; Lampton, Don

    2007-01-01

    ... or human role-players for each training event. We report our ongoing efforts to (1) research the nature and purpose of demonstration, articulating guidelines for effective demonstration within a training context, and (2...

  4. Comparing Demonstratives in Kwa

    African Journals Online (AJOL)

    This paper is a comparative study of demonstrative forms in three K wa languages, ... relative distance from the deictic centre, such as English this and that, here and there. ... Mostly, the referents of demonstratives are 'activated' or at least.

  5. Polarized Light Corridor Demonstrations.

    Science.gov (United States)

    Davies, G. R.

    1990-01-01

    Eleven demonstrations of light polarization are presented. Each includes a brief description of the apparatus and the effect demonstrated. Illustrated are strain patterns, reflection, scattering, the Faraday Effect, interference, double refraction, the polarizing microscope, and optical activity. (CW)

  6. Next-generation sequencing

    DEFF Research Database (Denmark)

    Rieneck, Klaus; Bak, Mads; Jønson, Lars

    2013-01-01

    , Illumina); several millions of PCR sequences were analyzed. RESULTS: The results demonstrated the feasibility of diagnosing the fetal KEL1 or KEL2 blood group from cell-free DNA purified from maternal plasma. CONCLUSION: This method requires only one primer pair, and the large amount of sequence...... information obtained allows well for statistical analysis of the data. This general approach can be integrated into current laboratory practice and has numerous applications. Besides DNA-based predictions of blood group phenotypes, platelet phenotypes, or sickle cell anemia, and the determination of zygosity...

  7. Strategy Guideline: Demonstration Home

    Energy Technology Data Exchange (ETDEWEB)

    Savage, C.; Hunt, A.

    2012-12-01

    This guideline will provide a general overview of the different kinds of demonstration home projects, a basic understanding of the different roles and responsibilities involved in the successful completion of a demonstration home, and an introduction into some of the lessons learned from actual demonstration home projects. Also, this guideline will specifically look at the communication methods employed during demonstration home projects. And lastly, we will focus on how to best create a communication plan for including an energy efficient message in a demonstration home project and carry that message to successful completion.

  8. Strategy Guideline. Demonstration Home

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A.; Savage, C.

    2012-12-01

    This guideline will provide a general overview of the different kinds of demonstration home projects, a basic understanding of the different roles and responsibilities involved in the successful completion of a demonstration home, and an introduction into some of the lessons learned from actual demonstration home projects. Also, this guideline will specifically look at the communication methods employed during demonstration home projects. And lastly, we will focus on how to best create a communication plan for including an energy efficient message in a demonstration home project and carry that message to successful completion.

  9. Manufacturing Demonstration Facility (MDF)

    Data.gov (United States)

    Federal Laboratory Consortium — The U.S. Department of Energy Manufacturing Demonstration Facility (MDF) at Oak Ridge National Laboratory (ORNL) provides a collaborative, shared infrastructure to...

  10. Latitudinal Patterns in European Seagrass Carbon Reserves: Influence of Seasonal Fluctuations versus Short-Term Stress and Disturbance Events

    Science.gov (United States)

    Soissons, Laura M.; Haanstra, Eeke P.; van Katwijk, Marieke M.; Asmus, Ragnhild; Auby, Isabelle; Barillé, Laurent; Brun, Fernando G.; Cardoso, Patricia G.; Desroy, Nicolas; Fournier, Jerome; Ganthy, Florian; Garmendia, Joxe-Mikel; Godet, Laurent; Grilo, Tiago F.; Kadel, Petra; Ondiviela, Barbara; Peralta, Gloria; Puente, Araceli; Recio, Maria; Rigouin, Loic; Valle, Mireia; Herman, Peter M. J.; Bouma, Tjeerd J.

    2018-01-01

    Seagrass meadows form highly productive and valuable ecosystems in the marine environment. Throughout the year, seagrass meadows are exposed to abiotic and biotic variations linked to (i) seasonal fluctuations, (ii) short-term stress events such as, e.g., local nutrient enrichment, and (iii) small-scale disturbances such as, e.g., biomass removal by grazing. We hypothesized that short-term stress events and small-scale disturbances may affect seagrass chance for survival in temperate latitudes. To test this hypothesis we focused on seagrass carbon reserves in the form of starch stored seasonally in rhizomes, as these have been defined as a good indicator for winter survival. Twelve Zostera noltei meadows were monitored along a latitudinal gradient in Western Europe to firstly assess the seasonal change of their rhizomal starch content. Secondly, we tested the effects of nutrient enrichment and/or biomass removal on the corresponding starch content by using a short-term manipulative field experiment at a single latitude in the Netherlands. At the end of the growing season, we observed a weak but significant linear increase of starch content along the latitudinal gradient from south to north. This agrees with the contention that such reserves are essential for regrowth after winter, which is more severe in the north. In addition, we also observed a weak but significant positive relationship between starch content at the beginning of the growing season and past winter temperatures. This implies a lower regrowth potential after severe winters, due to diminished starch content at the beginning of the growing season. Short-term stress and disturbances may intensify these patterns, because our manipulative experiments show that when nutrient enrichment and biomass loss co-occurred at the end of the growing season, Z. noltei starch content declined. In temperate zones, the capacity of seagrasses to accumulate carbon reserves is expected to determine carbon-based regrowth

  11. Latitudinal variations in intermediate depth ventilation and biological production over northeastern Pacific Oxygen Minimum Zones during the last 60 ka

    Science.gov (United States)

    Cartapanis, Olivier; Tachikawa, Kazuyo; Bard, Edouard

    2012-10-01

    Mechanisms affecting past variability in the Oxygen Minimum Zone (OMZ) in the Eastern Tropical North Pacific (ETNP) are poorly known. We analyzed core MD02-2524, obtained from the Nicaragua Margin in the present ETNP OMZ for major and minor elements (titanium (Ti), brome (Br), silicon (Si), potassium (K), and calcium (Ca)) using an X-ray Fluorescence (XRF) core scanner, and redox-sensitive trace elements (uranium (U), molybdenum (Mo), and nickel (Ni)) determined by ICP-MS. The U and Mo content was higher during the deglaciation than during the Holocene and the last glacial maximum, whereas enrichment was not observed for Ni, an element closely associated with organic matter. High-resolution XRF scanning indicated that the Ca-based carbonate content had millennial-scale variability inversely correlated with Br-based organic matter and Si/K-based opal content during the last glacial period. The available data suggest no clear regional trend in biological productivity during the last deglaciation, but significant local variability in the coastal eastern equatorial Pacific. The trace element enrichment and the lack of a concomitant increase in biogenic phases indicated that an enhanced ETNP OMZ, at least between 15°N and 12°N at a water depth of 500-900 m, was principally caused by a reduced oxygen supply driven by oceanic circulation to the Nicaragua Basin during the deglaciation. The observed patterns can be interpreted as the distinct changes in the oxygenation state of northern and southern water masses at intermediate depths. We also found evidence for a decoupling between local productivity and pore water oxygenation for several millennial-scale events during Marine Isotopic Stage 3, indicating that remote oxygen consumption and/or oceanic ventilation impacted OMZ intensity. Multi-millennial scale variations of the productivity at Papagayo upwelling cell displayed an opposite trend from productivity at the Costa Rica Dome, in relation with the latitudinal shift

  12. Latitudinal Patterns in European Seagrass Carbon Reserves: Influence of Seasonal Fluctuations versus Short-Term Stress and Disturbance Events

    Directory of Open Access Journals (Sweden)

    Laura M. Soissons

    2018-02-01

    Full Text Available Seagrass meadows form highly productive and valuable ecosystems in the marine environment. Throughout the year, seagrass meadows are exposed to abiotic and biotic variations linked to (i seasonal fluctuations, (ii short-term stress events such as, e.g., local nutrient enrichment, and (iii small-scale disturbances such as, e.g., biomass removal by grazing. We hypothesized that short-term stress events and small-scale disturbances may affect seagrass chance for survival in temperate latitudes. To test this hypothesis we focused on seagrass carbon reserves in the form of starch stored seasonally in rhizomes, as these have been defined as a good indicator for winter survival. Twelve Zostera noltei meadows were monitored along a latitudinal gradient in Western Europe to firstly assess the seasonal change of their rhizomal starch content. Secondly, we tested the effects of nutrient enrichment and/or biomass removal on the corresponding starch content by using a short-term manipulative field experiment at a single latitude in the Netherlands. At the end of the growing season, we observed a weak but significant linear increase of starch content along the latitudinal gradient from south to north. This agrees with the contention that such reserves are essential for regrowth after winter, which is more severe in the north. In addition, we also observed a weak but significant positive relationship between starch content at the beginning of the growing season and past winter temperatures. This implies a lower regrowth potential after severe winters, due to diminished starch content at the beginning of the growing season. Short-term stress and disturbances may intensify these patterns, because our manipulative experiments show that when nutrient enrichment and biomass loss co-occurred at the end of the growing season, Z. noltei starch content declined. In temperate zones, the capacity of seagrasses to accumulate carbon reserves is expected to determine carbon

  13. Latitudinal variation of life-history traits of an exotic and a native impatiens species in Europe

    Science.gov (United States)

    Acharya, Kamal Prasad; De Frenne, Pieter; Brunet, Jörg; Chabrerie, Olivier; Cousins, Sara A. O.; Diekmann, Martin; Hermy, Martin; Kolb, Annette; Lemke, Isgard; Plue, Jan; Verheyen, Kris; Graae, Bente Jessen

    2017-05-01

    Understanding the responses of invasive and native populations to environmental change is crucial for reliable predictions of invasions in the face of global change. While comparisons of responses across invasive species with different life histories have been performed before, comparing functional traits of congeneric native and invasive species may help to reveal driving factors associated with invasion. Here we compared morphological functional trait patterns of an invasive species (Impatiens parviflora) with its congeneric native species (I. noli-tangere) along an approximately 1600 km European latitudinal gradient from France (49°34‧N) to Norway (63°40‧N). Soil nitrogen was recorded during six weeks of the growing season, and light, soil moisture, and nutrient availability were estimated for each sampled population using community weighted means of indicator values for co-occurring species. Temperature data were gathered from nearby weather stations. Both the native and invasive species are taller at higher latitudes and this response is strongest in the invasive species. Seed mass and number of seeds per capsule increase in I. noli-tangere but decrease in I. parviflora towards higher latitudes. Surprisingly, plant height in the invasive I. parviflora decreases with increasing soil nitrogen availability. The latitudinal pattern in seed mass is positively related to temperature in I. noli-tangere and negatively in I. parviflora. Leaf area of both species decreases with increasing Ellenberg indicator values for nitrogen and light but increases with increasing soil moisture. Soil nitrogen concentrations and Ellenberg indicator values for nitrogen have significant positive (I. noli-tangere) and negative (I. parviflora) effects on the number of seeds per capsule. Our results show that the native I. noli-tangere has efficient reproduction at its range edge while the invasive I. parviflora shows a marked decrease in seed size and seed number per capsule. These

  14. Examining the relationship between mercury and organic matter in lake sediments along a latitudinal transect in subarctic Canada

    Science.gov (United States)

    Galloway, Jennifer M.; Sanei, Hamed; Parsons, Michael; Swindles, Graeme T.; Macumber, Andrew L.; Patterson, R. Timothy; Palmer, Michael; Falck, Hendrik

    2016-04-01

    The accumulation of Hg in aquatic environments at both high and low latitudes can be controlled by organic matter through algal scavenging, thus complicating the interpretation of historical Hg profiles in lake sediments1,2,3. However, other recent studies suggest that algal scavenging is not important in governing Hg flux to sediments4, in some cases because of dilution by inorganic materials5. This study examines relationships between Hg and organic matter (OM) in over 100 lakes located between 60.5 and 65.4 °N and crossing the latitudinal tree-line in subarctic Canada. The latitudinal gradient approach in our study offers an opportunity to better understand climate and environmental controls on OM accumulation and its role in influencing Hg deposition in subarctic lacustrine environments. We used Rock Eval 6 pyrolysis to determine total organic carbon (TOC%), S1 (soluble OM consisting of degradable lipids and algal pigments), S2 (OM derived from highly aliphatic biomacromolecule structure of algal cell walls), and S3 (OM dominated by carbohydrates, lignins, and plant materials). Total Hg in sediments was measured using thermal decomposition, amalgamation, and atomic absorption spectrophotometry. In these lake sediments, S2 composes the majority of TOC (Pearson's r = 0.978, porganic matter and mercury in recent lake sediment: the physical-geochemical aspects. Appl Geochem 21: 1900-12. 2Outridge, P.M., Sanei, H., Stern, G.A., Hamilton, P.B., Goodarzi, F. 2007. Evidence for control of mercury accumulation rates in Canadian high Arctic lake sediments by variations of aquatic primary productivity. Environ Sci Technol 41: 5259-65. 3Wu, F., Zu, L., Liao, H., Guo, F., Zhao, X., Giesy, J. 2013. Relationship between mercury and organic carbon in sediment cores from Lakes Qinghai and Chenghai, China. J Soils Sediments 13: 1084-1092.4Kirk, J.L., Muir, D.C.G., Antoniades, D., Douglas, M.S.V., Evans, M.S., Jackson, T.A., Kling, H., Lamoureux, S., Lim, D.S.S., Pienitz, R

  15. Latitudinal changes of euphausiid assemblages related to the morphological variability of the sound scattering layer along Baja California, October 1994

    Directory of Open Access Journals (Sweden)

    J. Gómez-Gutiérrez

    1999-03-01

    Full Text Available Latitudinal changes in the euphausiid assemblages were compared to the morphological structure (size and compactness of the sound scattering layer (SSL during ten 24-h surveys made in October 1994 along the west coast of Baja California, México. During October, upwelling was found in the northern area from Punta Eugenia (28°N to Ensenada (30°N dominated by temperate species from the California Current System. In the southern sector of the peninsula, a northward movement of tropical waters transports a tropical zooplankton assemblage near Bahia Magdalena (24°N. The aggregation and the dispersion of the whole SSL (plankton and nekton were investigated using a single beam vertical echosounder, Simrad EY-200, working at 200 kHz and the Hydro Acoustic Data Acquisition System (HADAS that estimates patch variables of density and compactness. The size and shape of the SSL were obtained from the echogram visualization. The euphausiid species composition was obtained using an Isaacs-Kidd midwater trawl, bongo nets, and opening-closing nets. At Ensenada and Punta Eugenia, an area inhabited by a temperate euphausiid assemblage, large and dense SSLs were recorded over the continental shelf (mean sizes were 10-km and 7-km long with mean compactness of 15% and 19%. These regions were dominated by the neritic species Nyctiphanes simplex and the temperate species Nematoscelis difficilis, Euphausia pacifica, and Thysanoessa spinifera. In the southern area, a tropical euphausiid assemblage, dominated by Euphausia eximia, E tenera, and E. distinguenda, inhabits smaller and dispersed SSLs (mean size 5-km long and 11% compactness located in the offshore area. The euphausiid biomass of the most abundant species indicated, N. simplex and N. difficilis, had their highest standing stock in the north (393 and 643 mg C 1000 m-3, with E. eximia in the southern area (186 mg C 1000 m-3. Euphausiid assemblage development in different biological environments, is evidenced

  16. Innovative technology demonstration

    International Nuclear Information System (INIS)

    Anderson, D.B.; Luttrell, S.P.; Hartley, J.N.; Hinchee, R.

    1992-04-01

    The Innovative Technology Demonstration (ITD) program at Tinker Air Force Base (TAFB), Oklahoma City, Oklahoma, will demonstrate the overall utility and effectiveness of innovative technologies for site characterization, monitoring, and remediation of selected contaminated test sites. The current demonstration test sites include a CERCLA site on the NPL list, located under a building (Building 3001) that houses a large active industrial complex used for rebuilding military aircraft, and a site beneath and surrounding an abandoned underground tank vault used for storage of jet fuels and solvents. The site under Building 3001 (the NW Test Site) is contaminated with TCE and Cr +6 ; the site with the fuel storage vault (the SW Tanks Site) is contaminated with fuels, BTEX and TCE. These sites and others have been identified for cleanup under the Air Force's Installation Restoration Program (IRP). This document describes the demonstrations that have been conducted or are planned for the TAFB

  17. Laser Communications Relay Demonstration

    Data.gov (United States)

    National Aeronautics and Space Administration — LCRD is a minimum two year flight demonstration in geosynchronous Earth orbit to advance optical communications technology toward infusion into Deep Space and Near...

  18. Spacecraft Fire Safety Demonstration

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the Spacecraft Fire Safety Demonstration project is to develop and conduct large-scale fire safety experiments on an International Space Station...

  19. Education Payload Operation - Demonstrations

    Science.gov (United States)

    Keil, Matthew

    2009-01-01

    Education Payload Operation - Demonstrations (EPO-Demos) are recorded video education demonstrations performed on the International Space Station (ISS) by crewmembers using hardware already onboard the ISS. EPO-Demos are videotaped, edited, and used to enhance existing NASA education resources and programs for educators and students in grades K-12. EPO-Demos are designed to support the NASA mission to inspire the next generation of explorers.

  20. Reproductive output of a non-zooxanthellate temperate coral is unaffected by temperature along an extended latitudinal gradient.

    Directory of Open Access Journals (Sweden)

    Valentina Airi

    Full Text Available Global environmental change, in marine ecosystems, is associated with concurrent shifts in water temperature, circulation, stratification, and nutrient input, with potentially wide-ranging biological effects. Variations in seawater temperature might alter physiological functioning, reproductive efficiency, and demographic traits of marine organisms, leading to shifts in population size and abundance. Differences in temperature tolerances between organisms can identify individual and ecological characteristics, which make corals able to persist and adapt in a climate change context. Here we investigated the possible effect of temperature on the reproductive output of the solitary non-zooxanthellate temperate coral Leptopsammia pruvoti, along an 8° latitudinal gradient. Samples have been collected in six populations along the gradient and each polyp was examined using histological and cyto-histometric analyses. We coupled our results with previous studies on the growth, demography, and calcification of L. pruvoti along the same temperature gradient, and compared them with those of another sympatric zooxanthellate coral Balanophyllia europaea to understand which trophic strategy makes the coral more tolerant to increasing temperature. The non-zooxanthellate species seemed to be quite tolerant to temperature increases, probably due to the lack of the symbiosis with zooxanthellae. To our knowledge, this is the first field investigation of the relationship between reproductive output and temperature increase of a temperate asymbiotic coral, providing novel insights into the poorly studied non-zooxanthellate scleractinians.

  1. Reproductive output of a non-zooxanthellate temperate coral is unaffected by temperature along an extended latitudinal gradient.

    Science.gov (United States)

    Airi, Valentina; Prantoni, Selena; Calegari, Marco; Lisini Baldi, Veronica; Gizzi, Francesca; Marchini, Chiara; Levy, Oren; Falini, Giuseppe; Dubinsky, Zvy; Goffredo, Stefano

    2017-01-01

    Global environmental change, in marine ecosystems, is associated with concurrent shifts in water temperature, circulation, stratification, and nutrient input, with potentially wide-ranging biological effects. Variations in seawater temperature might alter physiological functioning, reproductive efficiency, and demographic traits of marine organisms, leading to shifts in population size and abundance. Differences in temperature tolerances between organisms can identify individual and ecological characteristics, which make corals able to persist and adapt in a climate change context. Here we investigated the possible effect of temperature on the reproductive output of the solitary non-zooxanthellate temperate coral Leptopsammia pruvoti, along an 8° latitudinal gradient. Samples have been collected in six populations along the gradient and each polyp was examined using histological and cyto-histometric analyses. We coupled our results with previous studies on the growth, demography, and calcification of L. pruvoti along the same temperature gradient, and compared them with those of another sympatric zooxanthellate coral Balanophyllia europaea to understand which trophic strategy makes the coral more tolerant to increasing temperature. The non-zooxanthellate species seemed to be quite tolerant to temperature increases, probably due to the lack of the symbiosis with zooxanthellae. To our knowledge, this is the first field investigation of the relationship between reproductive output and temperature increase of a temperate asymbiotic coral, providing novel insights into the poorly studied non-zooxanthellate scleractinians.

  2. Differences in protein expression among five species of stream stonefly (Plecoptera) along a latitudinal gradient in Japan.

    Science.gov (United States)

    Gamboa, Maribet; Tsuchiya, Maria Claret; Matsumoto, Suguru; Iwata, Hisato; Watanabe, Kozo

    2017-11-01

    Proteome variation among natural populations along an environmental gradient may provide insights into how the biological functions of species are related to their local adaptation. We investigated protein expression in five stream stonefly species from four geographic regions along a latitudinal gradient in Japan with varying climatic conditions. The extracted proteins were separated by two-dimensional gel electrophoresis and identified by matrix-assisted laser desorption/ionization of time-of-flight (MALDI TOF/TOF), yielding 446 proteins. Low interspecies variation in the proteome profiles was observed among five species within geographical regions, presumably due to the co-occurring species sharing the environments. However, large spatial variations in protein expression were found among four geographic regions, suggesting strong regulation of protein expression in heterogeneous environments, where the spatial variations were positively correlated with water temperature. We identified 21 unique proteins expressed specifically in a geographical region and six common proteins expressed throughout all regions. In warmer regions, metabolic proteins were upregulated, whereas proteins related to cold stress, the photoperiod, and mating were downregulated. Oxygen-related and energy-production proteins were upregulated in colder regions with higher altitudes. Thus, our proteomic approach is useful for identifying and understanding important biological functions related to local adaptations by populations of stoneflies. © 2017 Wiley Periodicals, Inc.

  3. Aridity promotes bet hedging via delayed hatching: a case study with two temporary pond crustaceans along a latitudinal gradient.

    Science.gov (United States)

    Pinceel, Tom; Vanschoenwinkel, Bram; Hawinkel, Wouter; Tuytens, Karen; Brendonck, Luc

    2017-05-01

    Climate change does affect not only average rainfall and temperature but also their variation, which can reduce the predictability of suitable conditions for growth and reproduction. This situation is problematic for inhabitants of temporary waters whose reproductive success depends on rainfall and evaporation that determine the length of the aquatic phase. For organisms with long-lived dormant life stages, bet hedging models suggest that a fraction of these should stay dormant during each growing season to buffer against the probability of total reproductive failure in variable environments. Thus far, however, little empirical evidence supports this prediction in aquatic organisms. We study geographic variation in delayed hatching of dormant eggs in natural populations of two crustaceans, Branchinella longirostris and Paralimnadia badia, that occur in temporary rock pools along a 725 km latitudinal aridity gradient in Western Australia. Consistent with bet hedging theory, populations of both species were characterised by delayed hatching under common garden conditions and hatching fractions decreased towards the drier end of the gradient where the probability of reproductive success was shown to be lower. This decrease was most pronounced in the species with the longer maturation time, presumably because it is more sensitive to the higher prevalence of short inundations. Overall, these findings illustrate that regional variation in climate can be reflected in differential investment in bet hedging and hints at a higher importance of delayed hatching to persist when the climate becomes harsher. Such strategies could become exceedingly relevant as determinants of vulnerability under climate change.

  4. AFLP genome scanning reveals divergent selection in natural populations of Liriodendron chinense (Magnoliaceae along a latitudinal transect

    Directory of Open Access Journals (Sweden)

    Aihong eYang

    2016-05-01

    Full Text Available Understanding adaptive genetic variation and its relation to environmental factors are important for understanding how plants adapt to climate change and for managing genetic resources. Genome scans for the loci exhibiting either notably high or low levels of population differentiation (outlier loci provide one means of identifying genomic regions possibly associated with convergent or divergent selection. In this study, we combined AFLP genome scan and environmental association analysis to test for signals of natural selection in natural populations of Liriodendron chinense (Chinese Tulip Tree; Magnoliaceae along a latitudinal transect. We genotyped 276 individuals from 11 populations of L. chinense using 987 AFLP markers. Two complementary methods (Dfdist and BayeScan and association analysis between AFLP loci and climate factors were applied to detect outlier loci. Our analyses recovered both neutral and potentially adaptive genetic differentiation among populations of L. chinense. We found moderate genetic diversity within populations and high genetic differentiation among populations with reduced genetic diversity towards the periphery of the species ranges. Nine AFLP marker loci showed evidence of being outliers for population differentiation for both detection methods. Of these, six were strongly associated with at least one climate factor. Temperature, precipitation and radiation were found to be three important factors influencing local adaptation of L. chinense. The outlier AFLP loci are likely not the target of natural selection, but the neighboring genes of these loci might be involved in local adaptation. Hence, these candidates should be validated by further studies.

  5. Insect herbivores associated with Baccharis dracunculifolia (Asteraceae: responses of gall-forming and free-feeding insects to latitudinal variation

    Directory of Open Access Journals (Sweden)

    Marcílio Fagundes

    2011-09-01

    Full Text Available The spatial heterogeneity hypothesis has been invoked to explain the increase in species diversity from the poles to the tropics: the tropics may be more diverse because they contain more habitats and microhabitats. In this paper, the spatial heterogeneity hypothesis prediction was tested by evaluating the variation in richness of two guilds of insect herbivores (gall-formers and free-feeders associated with Baccharis dracunculifolia (Asteraceae along a latitudinal variation in Brazil. The seventeen populations of B. dracunculifolia selected for insect herbivores sampling were within structurally similar habitats, along the N-S distributional limit of the host plant, near the Brazilian sea coast. Thirty shrubs were surveyed in each host plant population. A total of 8 201 galls and 864 free-feeding insect herbivores belonging to 28 families and 88 species were sampled. The majority of the insects found on B. dracunculifolia were restricted to a specific site rather than having ageographic distribution mirroring that of the host plant. Species richness of free-feeding insects was not affected by latitudinal variation corroborating the spatial heterogeneity hypothesis. Species richness of gall-forming insects was positively correlated with latitude, probably because galling insect associated with Baccharris genus radiated in Southern Brazil. Other diversity indices and evenness estimated for both gall-forming and free feeding insect herbivores, did not change with latitude, suggesting a general structure for different assemblages of herbivores associated with the host plant B. dracunculifolia. Thus it is probable that, insect fauna sample in each site resulted of large scale events, as speciation, migration and coevolution, while at local level, the population of these insects is regulated by ecological forces which operate in the system. Rev. Biol. Trop. 59 (3: 1419-1432. Epub 2011 September 01.La hipótesis de heterogeneidad espacial se ha

  6. Longitudinal and latitudinal variations in dynamic characteristics of the MLT (70−95km: a study involving the CUJO network

    Directory of Open Access Journals (Sweden)

    A. H. Manson

    2004-01-01

    Full Text Available The newly-installed MFR (medium frequency radar at Platteville (40°N, 105°W has provided the opportunity and impetus to create an operational network of middle- latitude MFRs stretching from 81°W–142°E. CUJO (Canada U.S. Japan Opportunity comprises systems at London (43°N, 81°W, Platteville (40°N, 105°W, Saskatoon (52°N, 107°W, Wakkanai (45°N, 142°E and Yamagawa (31°N, 131°E. It offers a significant 7000km longitudinal sector in the North American-Pacific region, and a useful range of latitudes (12–14° at two longitudes. Annual climatologies involving both height and frequency versus time contour plots for periods from 8h to 30 days, show that the changes with longitude are very significant and distinctive, often exceeding the local latitudinal variations. Comparisons with models and the recent UARS-HRDI global analysis of tides are discussed. The fits of the horizontal wave numbers of the longer period oscillations are provided in unique frequency versus time contour plots and shown to be consistent with the expected dominant modes. Annual climatologies of planetary waves (16 day, 2 day and gravity waves reveal strong seasonal and longitudinal variations. Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; waves and tides; climatology

  7. Longitudinal and latitudinal variations in dynamic characteristics of the MLT (70-95km): a study involving the CUJO network

    Science.gov (United States)

    Manson, A.; Meek, C.; Chshyolkova, T.; Avery, S.; Thorsen, D.; MacDougall, J.; Hocking, W.; Murayama, Y.; Igarashi, K.; Namboothiri, S.; Kishore, P.

    2004-02-01

    . The newly-installed MFR (medium frequency radar) at Platteville (40N, 105W) has provided the opportunity and impetus to create an operational network of middle- latitude MFRs stretching from W-E. CUJO (Canada U.S. Japan Opportunity) comprises systems at London (N, 81W), Platteville (40N, 105W), Saskatoon (52N, 107W), Wakkanai (45N, 142E) and Yamagawa (31N, 131E). It offers a significant 7000km longitudinal sector in the North American-Pacific region, and a useful range of latitudes (12-14) at two longitudes. Annual climatologies involving both height and frequency versus time contour plots for periods from 8h to 30 days, show that the changes with longitude are very significant and distinctive, often exceeding the local latitudinal variations. Comparisons with models and the recent UARS-HRDI global analysis of tides are discussed. The fits of the horizontal wave numbers of the longer period oscillations are provided in unique frequency versus time contour plots and shown to be consistent with the expected dominant modes. Annual climatologies of planetary waves (16 day, 2 day) and gravity waves reveal strong seasonal and longitudinal variations.

  8. Buried Waste Integrated Demonstration

    International Nuclear Information System (INIS)

    1994-03-01

    The Buried Waste Integrated Demonstration (BWID) supports the applied research, development, demonstration, and evaluation of a suite of advanced technologies that offer promising solutions to the problems associated with the remediation of buried waste. BWID addresses the difficult remediation problems associated with DOE complex-wide buried waste, particularly transuranic (TRU) contaminated buried waste. BWID has implemented a systems approach to the development and demonstration of technologies that will characterize, retrieve, treat, and dispose of DOE buried wastes. This approach encompasses the entire remediation process from characterization to post-monitoring. The development and demonstration of the technology is predicated on how a technology fits into the total remediation process. To address all of these technological issues, BWID has enlisted scientific expertise of individuals and groups from within the DOE Complex, as well as experts from universities and private industry. The BWID mission is to support development and demonstration of a suite of technologies that, when integrated with commercially-available technologies, forms a comprehensive, remediation system for the effective and efficient remediation of buried waste throughout the DOE Complex. BWID will evaluate and validate demonstrated technologies and transfer this information and equipment to private industry to support the Office of Environmental Restoration (ER), Office of Waste Management (WM), and Office of Facility Transition (FT) remediation planning and implementation activities

  9. Seasonal acclimation and latitudinal adaptation are of the same magnitude in Mytilus edulis and Mytilus trossulus mitochondrial respiration

    DEFF Research Database (Denmark)

    Thyrring, Jakob; Bundgård, Amanda Marie; Sejr, Mikael Kristian

    2017-01-01

    Species distribution models often assume homogeneous physiological performance within a species distribution range. This assumption potentially underestimates the distribution as it neglects physiological plasticity and adaptation among species and populations. Better knowledge on the physiological......% after cold acclimation. Combined, our results show that seasonal variation in mitochondrial respiration is of the same magnitude as large-scale (>1000 km) latitudinal variation. The high respiratory plasticity in Mytilus spp. improves fitness in changing temperature environments and supports their large...

  10. Learning From Demonstration?

    DEFF Research Database (Denmark)

    Koch, Christian; Bertelsen, Niels Haldor

    2014-01-01

    Demonstration projects are often used in the building sector to provide a basis for using new processes and/or products. The climate change agenda implies that construction is not only required to deliver value for the customer, cost reductions and efficiency but also sustainable buildings....... This paper reports on an early demonstration project, the Building of a passive house dormitory in the Central Region of Denmark in 2006-2009. The project was supposed to deliver value, lean design, prefabrication, quality in sustainability, certification according to German standards for passive houses......, and micro combined heat and power using hydrogen. Using sociological and business economic theories of innovation, the paper discusses how early movers of innovation tend to obtain only partial success when demonstrating their products and often feel obstructed by minor details. The empirical work...

  11. Solar renovation demonstration projects

    Energy Technology Data Exchange (ETDEWEB)

    Bruun Joergensen, O [ed.

    1998-10-01

    In the framework of the IEA SHC Programme, a Task on building renovation was initiated, `Task 20, Solar Energy in Building Renovation`. In a part of the task, Subtask C `Design of Solar Renovation Projects`, different solar renovation demonstration projects were developed. The objective of Subtask C was to demonstrate the application of advanced solar renovation concepts on real buildings. This report documents 16 different solar renovation demonstration projects including the design processes of the projects. The projects include the renovation of houses, schools, laboratories, and factories. Several solar techniques were used: building integrated solar collectors, glazed balconies, ventilated solar walls, transparent insulation, second skin facades, daylight elements and photovoltaic systems. These techniques are used in several simple as well as more complex system designs. (au)

  12. Biodenitrification demonstration test report

    International Nuclear Information System (INIS)

    Benear, A.K.; Murray, S.J.; Lahoda, E.J.; Leslie, J.W.; Patton, J.B.; Menako, C.R.

    1987-08-01

    A two-column biodenitrification (BDN) facility was constructed at the Feed Materials Production Center (FMPC) in 1985 and 1986 to test the feasibility of biological treatment for industrial nitrate-bearing waste water generated at FMPC. This demonstration facility comprises one-half of the proposed four-column production facility. A demonstration test was conducted over a four month period in 1987. The results indicate the proposed BDN production facility can process FMPC industrial wastewater in a continuous manner while maintaining an effluent that will consistently meet the proposed NPDES limits for combined nitrate nitrogen (NO 3 -N) and nitrite nitrogen (NO 2 -N). The proposed NPDES limits are 62 kg/day average and 124 kg/day maximum. These limits were proportioned to determine that the two-column demonstration facility should meet the limits of 31 kg/day average and 62 kg/day maximum

  13. Distributed picture compilation demonstration

    Science.gov (United States)

    Alexander, Richard; Anderson, John; Leal, Jeff; Mullin, David; Nicholson, David; Watson, Graham

    2004-08-01

    A physical demonstration of distributed surveillance and tracking is described. The demonstration environment is an outdoor car park overlooked by a system of four rooftop cameras. The cameras extract moving objects from the scene, and these objects are tracked in a decentralized way, over a real communication network, using the information form of the standard Kalman filter. Each node therefore has timely access to the complete global picture and because there is no single point of failure in the system, it is robust. The demonstration system and its main components are described here, with an emphasis on some of the lessons we have learned as a result of applying a corpus of distributed data fusion theory and algorithms in practice. Initial results are presented and future plans to scale up the network are also outlined.

  14. Photovoltaic demonstration projects

    Energy Technology Data Exchange (ETDEWEB)

    Gillett, W B; Hacker, R J; Kaut, W [eds.

    1991-01-01

    This book, the proceedings of the fourth PV-Contractors' Meeting organized by the Commission of the European Communities, Directorate-General for Energy, held at Brussels on 21 and 22 November 1989, provides an overview of the photovoltaic demonstration projects which have been supported in the framework of the Energy Demonstration Program since 1983. It includes reports by each of the contractors who submitted proposals in 1983, 1984, 1985 and 1986, describing progress with their projects. Summaries of the discussions held at the meeting, which included contractors whose projects were submitted in 1987, are also presented. The different technologies which are being demonstrated concern the modules, the cabling of the array, structure design, storage strategy and power conditioning. The various applications include desalination, communications, dairy farms, water pumping, and warning systems. Papers have been processed separately for inclusion on the data base.

  15. Electric vehicle demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Ouellet, M. [National Centre for Advanced Transportation, Saint-Jerome, PQ (Canada)

    2010-07-01

    The desirable characteristics of Canadian projects that demonstrate vehicle use in real-world operation and the appropriate mechanism to collect and disseminate the monitoring data were discussed in this presentation. The scope of the project was on passenger cars and light duty trucks operating in plug-in electric vehicle (PHEV) or battery electric vehicle modes. The presentation also discussed the funding, stakeholders involved, Canadian travel pattern analysis, regulatory framework, current and recent electric vehicle demonstration projects, and project guidelines. It was concluded that some demonstration project activities may have been duplicated as communication between the proponents was insufficient. It was recommended that data monitoring using automatic data logging with minimum reliance on logbooks and other user entry should be emphasized. figs.

  16. Innovative technology demonstrations

    International Nuclear Information System (INIS)

    Anderson, D.B.; Luttrell, S.P.; Hartley, J.N.

    1992-08-01

    Environmental Management Operations (EMO) is conducting an Innovative Technology Demonstration Program for Tinker Air Force Base (TAFB). Several innovative technologies are being demonstrated to address specific problems associated with remediating two contaminated test sites at the base. Cone penetrometer testing (CPT) is a form of testing that can rapidly characterize a site. This technology was selected to evaluate its applicability in the tight clay soils and consolidated sandstone sediments found at TAFB. Directionally drilled horizontal wells was selected as a method that may be effective in accessing contamination beneath Building 3001 without disrupting the mission of the building, and in enhancing the extraction of contamination both in ground water and in soil. A soil gas extraction (SGE) demonstration, also known as soil vapor extraction, will evaluate the effectiveness of SGE in remediating fuels and TCE contamination contained in the tight clay soil formations surrounding the abandoned underground fuel storage vault located at the SW Tanks Site. In situ sensors have recently received much acclaim as a technology that can be effective in remediating hazardous waste sites. Sensors can be useful for determining real-time, in situ contaminant concentrations during the remediation process for performance monitoring and in providing feedback for controlling the remediation process. Following the SGE demonstration, the SGE system and SW Tanks test site will be modified to demonstrate bioremediation as an effective means of degrading the remaining contaminants in situ. The bioremediation demonstration will evaluate a bioventing process in which the naturally occurring consortium of soil bacteria will be stimulated to aerobically degrade soil contaminants, including fuel and TCE, in situ

  17. Innovative technology demonstrations

    International Nuclear Information System (INIS)

    Anderson, D.B.; Hartley, J.N.; Luttrell, S.P.

    1992-04-01

    Currently, several innovative technologies are being demonstrated at Tinker Air Force Base (TAFB) to address specific problems associated with remediating two contaminated test sites at the base. Cone penetrometer testing (CPT) is a form of testing that can rapidly characterize a site. This technology was selected to evaluate its applicability in the tight clay soils and consolidated sandstone sediments found at TAFB. Directionally drilled horizontal wells have been successfully installed at the US Department of Energy's (DOE) Savannah River Site to test new methods of in situ remediation of soils and ground water. This emerging technology was selected as a method that may be effective in accessing contamination beneath Building 3001 without disrupting the mission of the building, and in enhancing the extraction of contamination both in ground water and in soil. A soil gas extraction (SGE) demonstration, also known as soil vapor extraction, will evaluate the effectiveness of SGE in remediating fuels and TCE contamination contained in the tight clay soil formations surrounding the abandoned underground fuel storage vault located at the SW Tanks Site. In situ sensors have recently received much acclaim as a technology that can be effective in remediating hazardous waste sites. Sensors can be useful for determining real-time, in situ contaminant concentrations during the remediation process for performance monitoring and in providing feedback for controlling the remediation process. A demonstration of two in situ sensor systems capable of providing real-time data on contamination levels will be conducted and evaluated concurrently with the SGE demonstration activities. Following the SGE demonstration, the SGE system and SW Tanks test site will be modified to demonstrate bioremediation as an effective means of degrading the remaining contaminants in situ

  18. Gigashot Optical Laser Demonstrator

    Energy Technology Data Exchange (ETDEWEB)

    Deri, R. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-10-13

    The Gigashot Optical Laser Demonstrator (GOLD) project has demonstrated a novel optical amplifier for high energy pulsed lasers operating at high repetition rates. The amplifier stores enough pump energy to support >10 J of laser output, and employs conduction cooling for thermal management to avoid the need for expensive and bulky high-pressure helium subsystems. A prototype amplifier was fabricated, pumped with diode light at 885 nm, and characterized. Experimental results show that the amplifier provides sufficient small-signal gain and sufficiently low wavefront and birefringence impairments to prove useful in laser systems, at repetition rates up to 60 Hz.

  19. Photovoltaic demonstration projects 2

    Energy Technology Data Exchange (ETDEWEB)

    Gillett, W B; Hacker, R J [Halcrow (William) and Partners, Swindon (UK); Kaut, W [eds.

    1989-01-01

    This book, the proceedings of the third Photovoltaic Contractors' Meeting organised by the Commission of the European Communities, Directorate-General for Energy provides an overview of the photovoltaic demonstration projects which have been supported by the Energy Directorate of the Commission of the European Communities since 1983. It includes reports by each of the contractors who submitted proposals in 1983, 1984 and 1985, describing progress with their projects. The different technologies which are being demonstrated concern the modules, the cabling of the array, structure design, storage strategy and power conditioning. The various applications include powering of houses, villages, recreation centres, water desalination, communications, dairy farms, water pumping and warning systems. (author).

  20. Adding Feminist Therapy to Videotape Demonstrations.

    Science.gov (United States)

    Konrad, Jennifer L.; Yoder, Janice D.

    2000-01-01

    Provides directions for presenting a 32-minute series of four videotape segments that highlights the fundamental features of four approaches to psychotherapy, extending its reach to include a feminist perspective. Describes the approaches and included segments. Reports that students' comments demonstrate that the video sequence provided a helpful…

  1. Inseparable Phone Books Demonstration

    Science.gov (United States)

    Balta, Nuri; Çetin, Ali

    2017-01-01

    This study is aimed at first introducing a well-known discrepant event; inseparable phone books and second, turning it into an experiment for high school or middle school students. This discrepant event could be used especially to indicate how friction force can be effective in producing an unexpected result. Demonstration, discussion, explanation…

  2. PHARUS ASAR demonstrator

    NARCIS (Netherlands)

    Smith, A.J.E.; Bree, R.J.P. van; Calkoen, C.J.; Dekker, R.J.; Otten, M.P.G.; Rossum, W.L. van

    2001-01-01

    PHARUS is a polarimetric phased array C-band Synthetic Aperture Radar (SAR), designed and built for airborne use. Advanced SAR (ASAR) data in image and alternating polarization mode have been simulated with PHARUS to demonstrate the use of Envisat for a number of typical SAR applications that are

  3. Demonstrating the Gas Laws.

    Science.gov (United States)

    Holko, David A.

    1982-01-01

    Presents a complete computer program demonstrating the relationship between volume/pressure for Boyle's Law, volume/temperature for Charles' Law, and volume/moles of gas for Avagadro's Law. The programing reinforces students' application of gas laws and equates a simulated moving piston to theoretical values derived using the ideal gas law.…

  4. Astronomy LITE Demonstrations

    Science.gov (United States)

    Brecher, Kenneth

    2006-12-01

    Project LITE (Light Inquiry Through Experiments) is a materials, software, and curriculum development project. It focuses on light, optics, color and visual perception. According to two recent surveys of college astronomy faculty members, these are among the topics most often included in the large introductory astronomy courses. The project has aimed largely at the design and implementation of hands-on experiences for students. However, it has also included the development of lecture demonstrations that employ novel light sources and materials. In this presentation, we will show some of our new lecture demonstrations concerning geometrical and physical optics, fluorescence, phosphorescence and polarization. We have developed over 200 Flash and Java applets that can be used either by teachers in lecture settings or by students at home. They are all posted on the web at http://lite.bu.edu. For either purpose they can be downloaded directly to the user's computer or run off line. In lecture demonstrations, some of these applets can be used to control the light emitted by video projectors to produce physical effects in materials (e.g. fluorescence). Other applets can be used, for example, to demonstrate that the human percept of color does not have a simple relationship with the physical frequency of the stimulating source of light. Project LITE is supported by Grant #DUE-0125992 from the NSF Division of Undergraduate Education.

  5. A Magnetic Circuit Demonstration.

    Science.gov (United States)

    Vanderkooy, John; Lowe, June

    1995-01-01

    Presents a demonstration designed to illustrate Faraday's, Ampere's, and Lenz's laws and to reinforce the concepts through the analysis of a two-loop magnetic circuit. Can be made dramatic and challenging for sophisticated students but is suitable for an introductory course in electricity and magnetism. (JRH)

  6. Remote monitoring demonstration

    International Nuclear Information System (INIS)

    Caskey, Susan; Olsen, John

    2006-01-01

    The recently upgraded remote monitoring system at the Joyo Experimental Reactor uses a DCM-14 camera module and GEMINI software. The final data is compatible both with the IAEA-approved GARS review software and the ALIS software that was used for this demonstration. Features of the remote monitoring upgrade emphasized compatibility with IAEA practice. This presentation gives particular attention to the selection process for meeting network security considerations at the O'arai site. The Joyo system is different from the NNCA's ACPF system, in that it emphasizes use of IAEA standard camera technology and data acquisition and transmission software. In the demonstration itself, a temporary virtual private network (VPN) between the meeting room and the server at Sandia in Albuquerque allowed attendees to observe data stored from routine transmissions from the Joyo Fresh Fuel Storage to Sandia. Image files from a fuel movement earlier in the month showed Joyo workers and IAEA inspectors carrying out a transfer. (author)

  7. Commercial incineration demonstration

    International Nuclear Information System (INIS)

    Borduin, L.C.; Neuls, A.S.

    1981-01-01

    Low-level radioactive wastes (LLW) generated by nuclear utilities presently are shipped to commercial burial grounds for disposal. Substantially increasing shipping and disposal charges have sparked renewed industry interest in incineration and other advanced volume reduction techniques as potential cost-saving measures. Repeated inquiries from industry sources regarding LLW applicability of the Los Alamos controlled-air incineration (CAI) design led DOE to initiate this commercial demonstration program in FY-1980. The selected program approach to achieving CAI demonstration at a utility site is a DOE sponsored joint effort involving Los Alamos, a nuclear utility, and a liaison subcontractor. Required development tasks and responsibilities of the particpants are described. Target date for project completion is the end of FY-1985

  8. Photovoltaic demonstration projects

    Energy Technology Data Exchange (ETDEWEB)

    Kaut, W [Commission of the European Communities, Brussels (Belgium); Gillett, W B; Hacker, R J [Halcrow Gilbert Associates Ltd., Swindon (GB)

    1992-12-31

    This publication, comprising the proceedings of the fifth contractor`s meeting organized by the Commission of the European Communities, Directorate-General for Energy, provides an overview of the photovoltaic demonstration projects which have been supported in the framework of the energy demonstration programme since 1983. It includes reports by each of the contractors who submitted proposals in 1987 and 1988, describing progress within their projects. Projects accepted from earlier calls for proposals and not yet completed were reviewed by a rapporteur and are discussed in the summary section. The results of the performance monitoring of all projects and the lessons drawn from the practical experience of the projects are also presented in the summaries and conclusions. Contractors whose projects were submitted in 1989 were also present at the meeting and contributed to the reported discussions. This proceeding is divided into four sessions (General, Housing, technical presentations, other applications) and 24 papers are offered.

  9. AVNG system demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Thron, Jonathan Louis [Los Alamos National Laboratory; Mac Arthur, Duncan W [Los Alamos National Laboratory; Kondratov, Sergey [VNIIEF; Livke, Alexander [VNIIEF; Razinkov, Sergey [VNIIEF

    2010-01-01

    An attribute measurement system (AMS) measures a number of unclassified attributes of potentially classified material. By only displaying these unclassified results as red or green lights, the AMS protects potentially classified information while still generating confidence in the measurement result. The AVNG implementation that we describe is an AMS built by RFNC - VNIIEF in Sarov, Russia. To provide additional confidence, the AVNG was designed with two modes of operation. In the secure mode, potentially classified measurements can be made with only the simple red light/green light display. In the open mode, known unclassified material can be measured with complete display of the information collected from the radiation detectors. The AVNG demonstration, which occurred in Sarov, Russia in June 2009 for a joint US/Russian audience, included exercising both modes of AVNG operation using a number of multi-kg plutonium sources. In addition to describing the demonstration, we will show photographs and/or video taken of AVNG operation.

  10. Antares: preliminary demonstrator results

    International Nuclear Information System (INIS)

    Kouchner, A.

    2000-05-01

    The ANTARES collaboration is building an undersea neutrino telescope off Toulon (Mediterranean sea) with effective area ∼ 0.1 km 2 . An extensive study of the site properties has been achieved together with software analysis in order to optimize the performance of the detector. Results are summarized here. An instrumented line, linked to shore for first time via an electro-optical cable, has been immersed late 1999. The preliminary results of this demonstrator line are reported. (author)

  11. The Majorana Demonstrator

    Energy Technology Data Exchange (ETDEWEB)

    Aguayo, Estanislao; Fast, James E.; Hoppe, Eric W.; Keillor, Martin E.; Kephart, Jeremy D.; Kouzes, Richard T.; LaFerriere, Brian D.; Merriman, Jason H.; Orrell, John L.; Overman, Nicole R.; Avignone, Frank T.; Back, Henning O.; Combs, Dustin C.; Leviner, L.; Young, A.; Barabash, Alexander S.; Konovalov, S.; Vanyushin, I.; Yumatov, Vladimir; Bergevin, M.; Chan, Yuen-Dat; Detwiler, Jason A.; Loach, J. C.; Martin, R. D.; Poon, Alan; Prior, Gersende; Vetter, Kai; Bertrand, F.; Cooper, R. J.; Radford, D. C.; Varner, R. L.; Yu, Chang-Hong; Boswell, M.; Elliott, S.; Gehman, Victor M.; Hime, Andrew; Kidd, M. F.; LaRoque, B. H.; Rielage, Keith; Ronquest, M. C.; Steele, David; Brudanin, V.; Egorov, Viatcheslav; Gusey, K.; Kochetov, Oleg; Shirchenko, M.; Timkin, V.; Yakushev, E.; Busch, Matthew; Esterline, James H.; Tornow, Werner; Christofferson, Cabot-Ann; Horton, Mark; Howard, S.; Sobolev, V.; Collar, J. I.; Fields, N.; Creswick, R.; Doe, Peter J.; Johnson, R. A.; Knecht, A.; Leon, Jonathan D.; Marino, Michael G.; Miller, M. L.; Robertson, R. G. H.; Schubert, Alexis G.; Wolfe, B. A.; Efremenko, Yuri; Ejiri, H.; Hazama, R.; Nomachi, Masaharu; Shima, T.; Finnerty, P.; Fraenkle, Florian; Giovanetti, G. K.; Green, M.; Henning, Reyco; Howe, M. A.; MacMullin, S.; Phillips, D.; Snavely, Kyle J.; Strain, J.; Vorren, Kris R.; Guiseppe, Vincente; Keller, C.; Mei, Dong-Ming; Perumpilly, Gopakumar; Thomas, K.; Zhang, C.; Hallin, A. L.; Keeter, K.; Mizouni, Leila; Wilkerson, J. F.

    2011-09-03

    A brief review of the history and neutrino physics of double beta decay is given. A description of the MAJORANA DEMONSTRATOR research and development program, including background reduction techniques, is presented in some detail. The application of point contact (PC) detectors to the experiment is discussed, including the effectiveness of pulse shape analysis. The predicted sensitivity of a PC detector array enriched to 86% to 76Ge is given.

  12. IGCC technology and demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Palonen, J [A. Ahlstrom Corporation, Karhula (Finland). Hans Ahlstrom Lab.; Lundqvist, R G [A. Ahlstrom Corporation, Helsinki (Finland); Staahl, K [Sydkraft AB, Malmoe (Sweden)

    1997-12-31

    Future energy production will be performed by advanced technologies that are more efficient, more environmentally friendly and less expensive than current technologies. Integrated gasification combined cycle (IGCC) power plants have been proposed as one of these systems. Utilising biofuels in future energy production will also be emphasised since this lowers substantially carbon dioxide emissions into the atmosphere due to the fact that biomass is a renewable form of energy. Combining advanced technology and biomass utilisation is for this reason something that should and will be encouraged. A. Ahlstrom Corporation of Finland and Sydkraft AB of Sweden have as one part of company strategies adopted this approach for the future. The companies have joined their resources in developing a biomass-based IGCC system with the gasification part based on pressurised circulating fluidized-bed technology. With this kind of technology electrical efficiency can be substantially increased compared to conventional power plants. As a first concrete step, a decision has been made to build a demonstration plant. This plant, located in Vaernamo, Sweden, has already been built and is now in commissioning and demonstration stage. The system comprises a fuel drying plant, a pressurised CFB gasifier with gas cooling and cleaning, a gas turbine, a waste heat recovery unit and a steam turbine. The plant is the first in the world where the integration of a pressurised gasifier with a gas turbine will be realised utilising a low calorific gas produced from biomass. The capacity of the Vaernamo plant is 6 MW of electricity and 9 MW of district heating. Technology development is in progress for design of plants of sizes from 20 to 120 MWe. The paper describes the Bioflow IGCC system, the Vaernamo demonstration plant and experiences from the commissioning and demonstration stages. (orig.)

  13. IGCC technology and demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Palonen, J. [A. Ahlstrom Corporation, Karhula (Finland). Hans Ahlstrom Lab.; Lundqvist, R.G. [A. Ahlstrom Corporation, Helsinki (Finland); Staahl, K. [Sydkraft AB, Malmoe (Sweden)

    1996-12-31

    Future energy production will be performed by advanced technologies that are more efficient, more environmentally friendly and less expensive than current technologies. Integrated gasification combined cycle (IGCC) power plants have been proposed as one of these systems. Utilising biofuels in future energy production will also be emphasised since this lowers substantially carbon dioxide emissions into the atmosphere due to the fact that biomass is a renewable form of energy. Combining advanced technology and biomass utilisation is for this reason something that should and will be encouraged. A. Ahlstrom Corporation of Finland and Sydkraft AB of Sweden have as one part of company strategies adopted this approach for the future. The companies have joined their resources in developing a biomass-based IGCC system with the gasification part based on pressurised circulating fluidized-bed technology. With this kind of technology electrical efficiency can be substantially increased compared to conventional power plants. As a first concrete step, a decision has been made to build a demonstration plant. This plant, located in Vaernamo, Sweden, has already been built and is now in commissioning and demonstration stage. The system comprises a fuel drying plant, a pressurised CFB gasifier with gas cooling and cleaning, a gas turbine, a waste heat recovery unit and a steam turbine. The plant is the first in the world where the integration of a pressurised gasifier with a gas turbine will be realised utilising a low calorific gas produced from biomass. The capacity of the Vaernamo plant is 6 MW of electricity and 9 MW of district heating. Technology development is in progress for design of plants of sizes from 20 to 120 MWe. The paper describes the Bioflow IGCC system, the Vaernamo demonstration plant and experiences from the commissioning and demonstration stages. (orig.)

  14. Lunar Water Resource Demonstration

    Science.gov (United States)

    Muscatello, Anthony C.

    2008-01-01

    In cooperation with the Canadian Space Agency, the Northern Centre for Advanced Technology, Inc., the Carnegie-Mellon University, JPL, and NEPTEC, NASA has undertaken the In-Situ Resource Utilization (ISRU) project called RESOLVE. This project is a ground demonstration of a system that would be sent to explore permanently shadowed polar lunar craters, drill into the regolith, determine what volatiles are present, and quantify them in addition to recovering oxygen by hydrogen reduction. The Lunar Prospector has determined these craters contain enhanced hydrogen concentrations averaging about 0.1%. If the hydrogen is in the form of water, the water concentration would be around 1%, which would translate into billions of tons of water on the Moon, a tremendous resource. The Lunar Water Resource Demonstration (LWRD) is a part of RESOLVE designed to capture lunar water and hydrogen and quantify them as a backup to gas chromatography analysis. This presentation will briefly review the design of LWRD and some of the results of testing the subsystem. RESOLVE is to be integrated with the Scarab rover from CMIJ and the whole system demonstrated on Mauna Kea on Hawaii in November 2008. The implications of lunar water for Mars exploration are two-fold: 1) RESOLVE and LWRD could be used in a similar fashion on Mars to locate and quantify water resources, and 2) electrolysis of lunar water could provide large amounts of liquid oxygen in LEO, leading to lower costs for travel to Mars, in addition to being very useful at lunar outposts.

  15. Waste and Disposal: Demonstration

    International Nuclear Information System (INIS)

    Neerdael, B.; Buyens, M.; De Bruyn, D.; Volckaert, G.

    2002-01-01

    Within the Belgian R and D programme on geological disposal, demonstration experiments have become increasingly important. In this contribution to the scientific report 2001, an overview is given of SCK-CEN's activities and achievements in the field of large-scale demonstration experiments. In 2001, main emphasis was on the PRACLAY project, which is a large-scale experiment to demonstrate the construction and the operation of a gallery for the disposal of HLW in a clay formation. The PRACLAY experiment will contribute to enhance understanding of water flow and mass transport in dense clay-based materials as well as to improve the design of the reference disposal concept. In the context of PRACLAY, a surface experiment (OPHELIE) has been developed to prepare and to complement PRACLAY-related experimental work in the HADES Underground Research Laboratory. In 2001, efforts were focussed on the operation of the OPHELIE mock-up. SCK-CEN also contributed to the SELFRAC roject which studies the self-healing of fractures in a clay formation

  16. Constraints and trade-offs in climate-dependent adaptation: energy budgets and growth in a latitudinal cline

    Directory of Open Access Journals (Sweden)

    Hans O. Pörtner

    2005-12-01

    Full Text Available Characteristics of temperature-dependent metabolic adaptation as well as their implications for associated changes in energy budgets are analysed based on comparisons of fish and invertebrates from various latitudinal clines in northern and southern hemispheres and on integrated ecological and physiological approaches. To identify putative “bottlenecks” of adaptation and for a general cause and effect understanding, the temperature sensitivity of growth as a key energy budget component is investigated, considering underlying processes at population, whole animal and cellular levels. Available data support the hypothesis that natural selection favours individuals for energy efficiency and maximised growth, but is subject to constraints of limited energy availability and temperature. According to emerging relationships between energy turnover, temperature variability and thermal tolerance, the notion that selection should favour a certain metabolic rate according to mean temperature is too simplistic. Within the energy budget, savings in maintenance costs set free energy for growth, visible as growth increments at a low standard metabolic rate. Such energy savings are maximised at the permanently low temperature of the Antarctic. However, some variability persists as pelagic lifestyles in the Antarctic are fuelled by higher metabolic rates at the expense of reduced growth. Temperature variability in the cold, as in the Subarctic, causes a rise in maintenance costs at the expense of growth, but in favour of exercise and thus foraging capacity. Such transitions in energy cost between sub-polar and polar areas are not visible in the southern hemisphere, where there is less temperature variability. However, these patterns—as well as many of the underlying mechanisms—still remain incompletely investigated, especially with respect to the suggested hierarchy in energy allocation to energy budget components.

  17. Drift, selection, or migration? Processes affecting genetic differentiation and variation along a latitudinal gradient in an amphibian.

    Science.gov (United States)

    Cortázar-Chinarro, Maria; Lattenkamp, Ella Z; Meyer-Lucht, Yvonne; Luquet, Emilien; Laurila, Anssi; Höglund, Jacob

    2017-08-14

    Past events like fluctuations in population size and post-glacial colonization processes may influence the relative importance of genetic drift, migration and selection when determining the present day patterns of genetic variation. We disentangle how drift, selection and migration shape neutral and adaptive genetic variation in 12 moor frog populations along a 1700 km latitudinal gradient. We studied genetic differentiation and variation at a MHC exon II locus and a set of 18 microsatellites. Using outlier analyses, we identified the MHC II exon 2 (corresponding to the β-2 domain) locus and one microsatellite locus (RCO8640) to be subject to diversifying selection, while five microsatellite loci showed signals of stabilizing selection among populations. STRUCTURE and DAPC analyses on the neutral microsatellites assigned populations to a northern and a southern cluster, reflecting two different post-glacial colonization routes found in previous studies. Genetic variation overall was lower in the northern cluster. The signature of selection on MHC exon II was weaker in the northern cluster, possibly as a consequence of smaller and more fragmented populations. Our results show that historical demographic processes combined with selection and drift have led to a complex pattern of differentiation along the gradient where some loci are more divergent among populations than predicted from drift expectations due to diversifying selection, while other loci are more uniform among populations due to stabilizing selection. Importantly, both overall and MHC genetic variation are lower at northern latitudes. Due to lower evolutionary potential, the low genetic variation in northern populations may increase the risk of extinction when confronted with emerging pathogens and climate change.

  18. Methodology of satellite microwave diagnostics of latitudinal-zonal and seasonal variations of frozen soil and sea ice

    Directory of Open Access Journals (Sweden)

    V. V. Melentiev

    2013-01-01

    Full Text Available In the frame of the work we have had investigated the utility of 6.9GHz dual polarization passive microwave data from the sensor AMSR-E for quantitative assessment of spatial and temporal variations of permafrost, seasonally frozen grounds and sea ice properties along the transect 70° E in 2005–2008 years. Analysis of the factors which could be detected with using study of the spatial-temporal variations of the microwave emissivity (brightness temperatures of the system «Earth-atmosphere» was carried out with using in situ data obtained from meteorological stations situated along the investigated transect of the Western Siberia and geocryologic station Marre-Sale (Yamal Peninsula. A new method of visualization of the brightness temperatures in spatial-temporal dimensions was suggested and practical applied. Eight latitudinal zones with intrinsic peculiarities of the spatial and seasonal variability of the brightness temperatures were revealed and investigated in many details. Comparison of the location of these zones with geographic distribution of biomes in Western Siberia was provided and it shows that satellite passive microwave information can be used for classification of the territories inside biomes. In frame of this study the annual brightness temperatures course for tundra zone area has been strictly divided into four periods (seasons characterized by different types of microwave emissivity variations. For boreal needle-leaved forest zone these seasons are manifested weaker. Comprehensive analysis of the satellite microwave survey data and corresponding the in situ data has shown satisfactory correlation between the brightness temperatures of the tundra areas on the Yamal Peninsula and their thermodynamic ground-trough temperatures at the square of geocryologic station Marre-Sale during winter period of stable frozen conditions and vegetation period. In these periods one-channel satellite microwave survey could be applied for the

  19. Dependence of Arctic climate on the latitudinal position of stationary waves and to high-latitudes surface warming

    Science.gov (United States)

    Shin, Yechul; Kang, Sarah M.; Watanabe, Masahiro

    2017-12-01

    Previous studies suggest large uncertainties in the stationary wave response under global warming. Here, we investigate how the Arctic climate responds to changes in the latitudinal position of stationary waves, and to high-latitudes surface warming that mimics the effect of Arctic sea ice loss under global warming. To generate stationary waves in an atmospheric model coupled to slab ocean, a series of experiments is performed where the thermal forcing with a zonal wavenumber-2 (with zero zonal-mean) is prescribed at the surface at different latitude bands in the Northern Hemisphere. When the stationary waves are generated in the subtropics, the cooling response dominates over the warming response in the lower troposphere due to cloud radiative effects. Then, the low-level baroclinicity is reduced in the subtropics, which gives rise to a poleward shift of the eddy driven jet, thereby inducing substantial cooling in the northern high latitudes. As the stationary waves are progressively generated at higher latitudes, the zonal-mean climate state gradually becomes more similar to the integration with no stationary waves. These differences in the mean climate affect the Arctic climate response to high-latitudes surface warming. Additional surface heating over the Arctic is imposed to the reference climates in which the stationary waves are located at different latitude bands. When the stationary waves are positioned at lower latitudes, the eddy driven jet is located at higher latitude, closer to the prescribed Arctic heating. As baroclinicity is more effectively perturbed, the jet shifts more equatorward that accompanies a larger reduction in the poleward eddy transport of heat and momentum. A stronger eddy-induced descending motion creates greater warming over the Arctic. Our study calls for a more accurate simulation of the present-day stationary wave pattern to enhance the predictability of the Arctic warming response in a changing climate.

  20. Spatial analyses of benthic habitats to define coral reef ecosystem regions and potential biogeographic boundaries along a latitudinal gradient.

    Directory of Open Access Journals (Sweden)

    Brian K Walker

    Full Text Available Marine organism diversity typically attenuates latitudinally from tropical to colder climate regimes. Since the distribution of many marine species relates to certain habitats and depth regimes, mapping data provide valuable information in the absence of detailed ecological data that can be used to identify and spatially quantify smaller scale (10 s km coral reef ecosystem regions and potential physical biogeographic barriers. This study focused on the southeast Florida coast due to a recognized, but understudied, tropical to subtropical biogeographic gradient. GIS spatial analyses were conducted on recent, accurate, shallow-water (0-30 m benthic habitat maps to identify and quantify specific regions along the coast that were statistically distinct in the number and amount of major benthic habitat types. Habitat type and width were measured for 209 evenly-spaced cross-shelf transects. Evaluation of groupings from a cluster analysis at 75% similarity yielded five distinct regions. The number of benthic habitats and their area, width, distance from shore, distance from each other, and LIDAR depths were calculated in GIS and examined to determine regional statistical differences. The number of benthic habitats decreased with increasing latitude from 9 in the south to 4 in the north and many of the habitat metrics statistically differed between regions. Three potential biogeographic barriers were found at the Boca, Hillsboro, and Biscayne boundaries, where specific shallow-water habitats were absent further north; Middle Reef, Inner Reef, and oceanic seagrass beds respectively. The Bahamas Fault Zone boundary was also noted where changes in coastal morphologies occurred that could relate to subtle ecological changes. The analyses defined regions on a smaller scale more appropriate to regional management decisions, hence strengthening marine conservation planning with an objective, scientific foundation for decision making. They provide a framework

  1. Analysis of temporal-longitudinal-latitudinal characteristics in the global ionosphere based on tensor rank-1 decomposition

    Science.gov (United States)

    Lu, Shikun; Zhang, Hao; Li, Xihai; Li, Yihong; Niu, Chao; Yang, Xiaoyun; Liu, Daizhi

    2018-03-01

    Combining analyses of spatial and temporal characteristics of the ionosphere is of great significance for scientific research and engineering applications. Tensor decomposition is performed to explore the temporal-longitudinal-latitudinal characteristics in the ionosphere. Three-dimensional tensors are established based on the time series of ionospheric vertical total electron content maps obtained from the Centre for Orbit Determination in Europe. To obtain large-scale characteristics of the ionosphere, rank-1 decomposition is used to obtain U^{(1)}, U^{(2)}, and U^{(3)}, which are the resulting vectors for the time, longitude, and latitude modes, respectively. Our initial finding is that the correspondence between the frequency spectrum of U^{(1)} and solar variation indicates that rank-1 decomposition primarily describes large-scale temporal variations in the global ionosphere caused by the Sun. Furthermore, the time lags between the maxima of the ionospheric U^{(2)} and solar irradiation range from 1 to 3.7 h without seasonal dependence. The differences in time lags may indicate different interactions between processes in the magnetosphere-ionosphere-thermosphere system. Based on the dataset displayed in the geomagnetic coordinates, the position of the barycenter of U^{(3)} provides evidence for north-south asymmetry (NSA) in the large-scale ionospheric variations. The daily variation in such asymmetry indicates the influences of solar ionization. The diurnal geomagnetic coordinate variations in U^{(3)} show that the large-scale EIA (equatorial ionization anomaly) variations during the day and night have similar characteristics. Considering the influences of geomagnetic disturbance on ionospheric behavior, we select the geomagnetic quiet GIMs to construct the ionospheric tensor. The results indicate that the geomagnetic disturbances have little effect on large-scale ionospheric characteristics.

  2. High-resolution 3-μm spectra of Jupiter: Latitudinal spectral variations influenced by molecules, clouds, and haze

    Science.gov (United States)

    Kim, Sang J.; Geballe, T. R.; Kim, J. H.; Jung, A.; Seo, H. J.; Minh, Y. C.

    2010-08-01

    We present latitudinally-resolved high-resolution ( R = 37,000) pole-to-pole spectra of Jupiter in various narrow longitudinal ranges, in spectral intervals covering roughly half of the spectral range 2.86-3.53 μm. We have analyzed the data with the aid of synthetic spectra generated from a model jovian atmosphere that included lines of CH 4, CH 3D, NH 3, C 2H 2, C 2H 6, PH 3, and HCN, as well as clouds and haze. Numerous spectral features of many of these molecular species are present and are individually identified for the first time, as are many lines of H3+ and a few unidentified spectral features. In both polar regions the 2.86-3.10-μm continuum is more than 10 times weaker than in spectra at lower latitudes, implying that in this wavelength range the single-scattering albedos of polar haze particles are very low. In contrast, the 3.24-3.53 μm the weak polar and equatorial continua are of comparable intensity. We derive vertical distributions of NH 3, C 2H 2 and C 2H 6, and find that the mixing ratios of NH 3 and C 2H 6 show little variation between equatorial and polar regions. However, the mixing ratios of C 2H 2 in the northern and southern polar regions are ˜6 and ˜3 times, respectively, less than those in the equatorial regions. The derived mixing ratio curves of C 2H 2 and C 2H 6 extend up to the 10 -6 bar level, a significantly higher altitude than most previous results in the literature. Further ground-based observations covering other longitudes are needed to test if these mixing ratios are representative values for the equatorial and polar regions.

  3. Latitudinal and seasonal variability of the micrometeor input function: A study using model predictions and observations from Arecibo and PFISR

    Science.gov (United States)

    Fentzke, J. T.; Janches, D.; Sparks, J. J.

    2009-05-01

    In this work, we use a semi-empirical model of the micrometeor input function (MIF) together with meteor head-echo observations obtained with two high power and large aperture (HPLA) radars, the 430 MHz Arecibo Observatory (AO) radar in Puerto Rico (18°N, 67°W) and the 450 MHz Poker flat incoherent scatter radar (PFISR) in Alaska (65°N, 147°W), to study the seasonal and geographical dependence of the meteoric flux in the upper atmosphere. The model, recently developed by Janches et al. [2006a. Modeling the global micrometeor input function in the upper atmosphere observed by high power and large aperture radars. Journal of Geophysical Research 111] and Fentzke and Janches [2008. A semi-empirical model of the contribution from sporadic meteoroid sources on the meteor input function observed at arecibo. Journal of Geophysical Research (Space Physics) 113 (A03304)], includes an initial mass flux that is provided by the six known meteor sources (i.e. orbital families of dust) as well as detailed modeling of meteoroid atmospheric entry and ablation physics. In addition, we use a simple ionization model to treat radar sensitivity issues by defining minimum electron volume density production thresholds required in the meteor head-echo plasma for detection. This simplified approach works well because we use observations from two radars with similar frequencies, but different sensitivities and locations. This methodology allows us to explore the initial input of particles and how it manifests in different parts of the MLT as observed by these instruments without the need to invoke more sophisticated plasma models, which are under current development. The comparisons between model predictions and radar observations show excellent agreement between diurnal, seasonal, and latitudinal variability of the detected meteor rate and radial velocity distributions, allowing us to understand how individual meteoroid populations contribute to the overall flux at a particular

  4. Temperature regulation of marine heterotrophic prokaryotes increases latitudinally as a breach between bottom-up and top-down controls

    KAUST Repository

    Moran, Xose Anxelu G.

    2017-04-19

    Planktonic heterotrophic prokaryotes make up the largest living biomass and process most organic matter in the ocean. Determining when and where the biomass and activity of heterotrophic prokaryotes are controlled by resource availability (bottom-up), predation and viral lysis (top-down) or temperature will help in future carbon cycling predictions. We conducted an extensive survey across subtropical and tropical waters of the Atlantic, Indian and Pacific Oceans during the Malaspina 2010 Global Circumnavigation Expedition and assessed indices for these three types of controls at 109 stations (mostly from the surface to 4000 m depth). Temperature control was approached by the apparent activation energy in eV (ranging from 0.46 to 3.41), bottom-up control by the slope of the log-log relationship between biomass and production rate (ranging from -0.12 to 1.09) and top-down control by an index that considers the relative abundances of heterotrophic nanoflagellates and viruses (ranging from 0.82 to 4.83). We conclude that temperature becomes dominant (i.e. activation energy >1.5 eV) within a narrow window of intermediate values of bottom-up (0.3-0.6) and top-down 0.8-1.2) controls. A pervasive latitudinal pattern of decreasing temperature regulation towards the Equator, regardless of the oceanic basin, suggests that the impact of global warming on marine microbes and their biogeochemical function will be more intense at higher latitudes. Our analysis predicts that 1°C ocean warming will result in increased biomass of heterotrophic prokaryoplankton only in waters with <26°C of mean annual surface temperature. This article is protected by copyright. All rights reserved.

  5. Germination responses to current and future temperatures of four seeder shrubs across a latitudinal gradient in western Iberia.

    Science.gov (United States)

    Chamorro, Daniel; Luna, Belén; Moreno, José M

    2017-01-01

    Species differ in their temperature germination niche. Populations of a species may similarly differ across the distribution range of the species. Anticipating the impacts of climate variability and change requires understanding the differential sensitivity to germination temperature among and within species. Here we studied the germination responses of four hard-seeded Cistaceae seeders to a range of current and future temperatures. Seeds were collected at sites across the Iberian Peninsula and exposed or not exposed to a heat shock to break dormancy, then set to germinate under four temperature regimes. Temperatures were varied daily and seasonally, simulating the temperature range across the gradient, plus an increased temperature simulating future climate. Time to germination onset and cumulative germination at the end of each season were analyzed for the effects of temperature treatments, seasons, and local climate (temperature of the germination period, T gp ) at each site. T gp was a significant covariate of germination in all species but Cistus populifolius. Temperature treatments significantly affected Cistus ladanifer, C. salviifolius, and Halimium ocymoides. Germination occurred in simulated autumn conditions, with little germination occurring at later seasons, except in unheated seeds of H. ocymoides. Exposure to a heat shock changed the sensitivity to temperature treatments and the relationships with T gp . Germination responses to temperature differ not only among species but also within species across their latitudinal range. The responses were idiosyncratic and related to the local climate of the population. This germination variability complicates generalizing the impacts of climate variability and climate change. © 2017 Botanical Society of America.

  6. The origin of soil organic matter controls its composition and bioreactivity across a mesic boreal forest latitudinal gradient

    Science.gov (United States)

    Kohl, L.; Philben, M. J.; Edwards, K. A.; Podrebarac, F. A.; Jamie, W.; Ziegler, S. E.

    2017-12-01

    Warmer climates have been associated with reduced soil organic matter (SOM) bioreactivity, lower respiration rates at a given temperature, which is typically attributed to the presence of more decomposed SOM. Cross site studies, however, indicate that ecosystem regime shifts associated with long-term climate warming can affect SOM properties through changes in vegetation and plant litter inputs to soils. The relative importance of these two controls, diagenesis and inputs, on SOM properties as ecosystems experience climate warming remains poorly understood. To address this, we characterized the elemental, chemical (nuclear magnetic resonance spectroscopy and total hydrolysable amino acids), and isotopic composition of plant litter and SOM across a well-constrained mesic boreal forest latitudinal transect in Atlantic Canada. Results across forest sites within each of three climate regions indicated that (1) climate history and diagenesis affect distinct parameters of SOM chemistry, (2) increases in SOM bioreactivity with latitude were associated with elevated proportions of carbohydrates relative to plant waxes and lignin, and (3) despite the common forest type across regions, differences in SOM chemistry by climate region were associated with chemically distinct litter inputs and not different degrees of diagenesis. Climate effects on vascular plant litter chemistry explained only part of the regional differences in SOM chemistry, most notably the higher protein content of SOM from warmer regions. Greater proportions of lignin and aliphatic compounds and smaller proportions of carbohydrates in warmer sites' soils were explained by the higher proportion of vascular plant relative to moss litter in the warmer forests. These results indicate that a climate induced decrease in the proportion of moss inputs will not only impact SOM chemistry but also increase the resistance of SOM to decomposition, thus significantly altering SOM cycling in these boreal forest soils.

  7. Memory and learning with rapid audiovisual sequences

    Science.gov (United States)

    Keller, Arielle S.; Sekuler, Robert

    2015-01-01

    We examined short-term memory for sequences of visual stimuli embedded in varying multisensory contexts. In two experiments, subjects judged the structure of the visual sequences while disregarding concurrent, but task-irrelevant auditory sequences. Stimuli were eight-item sequences in which varying luminances and frequencies were presented concurrently and rapidly (at 8 Hz). Subjects judged whether the final four items in a visual sequence identically replicated the first four items. Luminances and frequencies in each sequence were either perceptually correlated (Congruent) or were unrelated to one another (Incongruent). Experiment 1 showed that, despite encouragement to ignore the auditory stream, subjects' categorization of visual sequences was strongly influenced by the accompanying auditory sequences. Moreover, this influence tracked the similarity between a stimulus's separate audio and visual sequences, demonstrating that task-irrelevant auditory sequences underwent a considerable degree of processing. Using a variant of Hebb's repetition design, Experiment 2 compared musically trained subjects and subjects who had little or no musical training on the same task as used in Experiment 1. Test sequences included some that intermittently and randomly recurred, which produced better performance than sequences that were generated anew for each trial. The auditory component of a recurring audiovisual sequence influenced musically trained subjects more than it did other subjects. This result demonstrates that stimulus-selective, task-irrelevant learning of sequences can occur even when such learning is an incidental by-product of the task being performed. PMID:26575193

  8. Memory and learning with rapid audiovisual sequences.

    Science.gov (United States)

    Keller, Arielle S; Sekuler, Robert

    2015-01-01

    We examined short-term memory for sequences of visual stimuli embedded in varying multisensory contexts. In two experiments, subjects judged the structure of the visual sequences while disregarding concurrent, but task-irrelevant auditory sequences. Stimuli were eight-item sequences in which varying luminances and frequencies were presented concurrently and rapidly (at 8 Hz). Subjects judged whether the final four items in a visual sequence identically replicated the first four items. Luminances and frequencies in each sequence were either perceptually correlated (Congruent) or were unrelated to one another (Incongruent). Experiment 1 showed that, despite encouragement to ignore the auditory stream, subjects' categorization of visual sequences was strongly influenced by the accompanying auditory sequences. Moreover, this influence tracked the similarity between a stimulus's separate audio and visual sequences, demonstrating that task-irrelevant auditory sequences underwent a considerable degree of processing. Using a variant of Hebb's repetition design, Experiment 2 compared musically trained subjects and subjects who had little or no musical training on the same task as used in Experiment 1. Test sequences included some that intermittently and randomly recurred, which produced better performance than sequences that were generated anew for each trial. The auditory component of a recurring audiovisual sequence influenced musically trained subjects more than it did other subjects. This result demonstrates that stimulus-selective, task-irrelevant learning of sequences can occur even when such learning is an incidental by-product of the task being performed.

  9. Demonstration of HITEX

    International Nuclear Information System (INIS)

    Morrison, H.D.; Woodall, K.B.

    1993-01-01

    A model reactor for HITEX successfully demonstrated the concept of high-temperature isotopic exchange in a closed loop simulating the conditions for fusion fuel cleanup. The catalyst of platinum on alumina pellets provided a surface area large enough to operate the reactor at 400 degrees celsius with flow rates up to 2 L/min. A 15-L tank containing a mixture of 4% CD 4 in H 2 was depleted in deuterium within 75 minutes down to 100 ppm HD above the natural concentration of HD in the make-up hydrogen stream. The application to tritium removal from tritiated impurities in a hydrogen stream will work as well or better

  10. Visual Electricity Demonstrator

    Science.gov (United States)

    Lincoln, James

    2017-09-01

    The Visual Electricity Demonstrator (VED) is a linear diode array that serves as a dynamic alternative to an ammeter. A string of 48 red light-emitting diodes (LEDs) blink one after another to create the illusion of a moving current. Having the current represented visually builds an intuitive and qualitative understanding about what is happening in a circuit. In this article, I describe several activities for this device and explain how using this technology in the classroom can enhance the understanding and appreciation of physics.

  11. Exploration Medical System Demonstration

    Science.gov (United States)

    Rubin, D. A.; Watkins, S. D.

    2014-01-01

    BACKGROUND: Exploration class missions will present significant new challenges and hazards to the health of the astronauts. Regardless of the intended destination, beyond low Earth orbit a greater degree of crew autonomy will be required to diagnose medical conditions, develop treatment plans, and implement procedures due to limited communications with ground-based personnel. SCOPE: The Exploration Medical System Demonstration (EMSD) project will act as a test bed on the International Space Station (ISS) to demonstrate to crew and ground personnel that an end-to-end medical system can assist clinician and non-clinician crew members in optimizing medical care delivery and data management during an exploration mission. Challenges facing exploration mission medical care include limited resources, inability to evacuate to Earth during many mission phases, and potential rendering of medical care by non-clinicians. This system demonstrates the integration of medical devices and informatics tools for managing evidence and decision making and can be designed to assist crewmembers in nominal, non-emergent situations and in emergent situations when they may be suffering from performance decrements due to environmental, physiological or other factors. PROJECT OBJECTIVES: The objectives of the EMSD project are to: a. Reduce or eliminate the time required of an on-orbit crew and ground personnel to access, transfer, and manipulate medical data. b. Demonstrate that the on-orbit crew has the ability to access medical data/information via an intuitive and crew-friendly solution to aid in the treatment of a medical condition. c. Develop a common data management framework that can be ubiquitously used to automate repetitive data collection, management, and communications tasks for all activities pertaining to crew health and life sciences. d. Ensure crew access to medical data during periods of restricted ground communication. e. Develop a common data management framework that

  12. Commercial incineration demonstration

    International Nuclear Information System (INIS)

    Vavruska, J.S.; Borduin, L.C.

    1982-01-01

    Low-level radioactive wastes (LLW) generated by nuclear utilities presently are shipped to commercial burial grounds for disposal. Increasing transportation and disposal costs have caused industry to consider incineration as a cost-effective means of volume reduction of combustible LLW. Repeated inquiries from the nuclear industry regarding the applicability of the Los Alamos controlled air incineration (CAI) design led the DOE to initiate a commercial demonstration program in FY-1980. Development studies and results in support of this program involving ion exchange resin incineration and fission/activation product distributions within the Los Alamos CAI are described

  13. Demonstration tokamak power plant

    International Nuclear Information System (INIS)

    Abdou, M.; Baker, C.; Brooks, J.; Ehst, D.; Mattas, R.; Smith, D.L.; DeFreece, D.; Morgan, G.D.; Trachsel, C.

    1983-01-01

    A conceptual design for a tokamak demonstration power plant (DEMO) was developed. A large part of the study focused on examining the key issues and identifying the R and D needs for: (1) current drive for steady-state operation, (2) impurity control and exhaust, (3) tritium breeding blanket, and (4) reactor configuration and maintenance. Impurity control and exhaust will not be covered in this paper but is discussed in another paper in these proceedings, entitled Key Issues of FED/INTOR Impurity Control System

  14. Smart Grid Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Craig [National Rural Electric Cooperative Association, Arlington, VA (United States); Carroll, Paul [National Rural Electric Cooperative Association, Arlington, VA (United States); Bell, Abigail [National Rural Electric Cooperative Association, Arlington, VA (United States)

    2015-03-11

    The National Rural Electric Cooperative Association (NRECA) organized the NRECA-U.S. Department of Energy (DOE) Smart Grid Demonstration Project (DE-OE0000222) to install and study a broad range of advanced smart grid technologies in a demonstration that spanned 23 electric cooperatives in 12 states. More than 205,444 pieces of electronic equipment and more than 100,000 minor items (bracket, labels, mounting hardware, fiber optic cable, etc.) were installed to upgrade and enhance the efficiency, reliability, and resiliency of the power networks at the participating co-ops. The objective of this project was to build a path for other electric utilities, and particularly electrical cooperatives, to adopt emerging smart grid technology when it can improve utility operations, thus advancing the co-ops’ familiarity and comfort with such technology. Specifically, the project executed multiple subprojects employing a range of emerging smart grid technologies to test their cost-effectiveness and, where the technology demonstrated value, provided case studies that will enable other electric utilities—particularly electric cooperatives— to use these technologies. NRECA structured the project according to the following three areas: Demonstration of smart grid technology; Advancement of standards to enable the interoperability of components; and Improvement of grid cyber security. We termed these three areas Technology Deployment Study, Interoperability, and Cyber Security. Although the deployment of technology and studying the demonstration projects at coops accounted for the largest portion of the project budget by far, we see our accomplishments in each of the areas as critical to advancing the smart grid. All project deliverables have been published. Technology Deployment Study: The deliverable was a set of 11 single-topic technical reports in areas related to the listed technologies. Each of these reports has already been submitted to DOE, distributed to co-ops, and

  15. Electrodynamic Dust Shield Demonstrator

    Science.gov (United States)

    Stankie, Charles G.

    2013-01-01

    The objective of the project was to design and manufacture a device to demonstrate a new technology developed by NASA's Electrostatics and Surface Physics Laboratory. The technology itself is a system which uses magnetic principles to remove regolith dust from its surface. This project was to create an enclosure that will be used to demonstrate the effectiveness of the invention to The Office of the Chief Technologist. ONE of the most important challenges of space exploration is actually caused by something very small and seemingly insignificant. Dust in space, most notably on the moon and Mars, has caused many unforeseen issues. Dirt and dust on Earth, while a nuisance, can be easily cleaned and kept at bay. However, there is considerably less weathering and erosion in space. As a result, the microscopic particles are extremely rough and abrasive. They are also electrostatically charged, so they cling to everything they make contact with. This was first noted to be a major problem during the Apollo missions. Dust would stick to the spacesuits, and could not be wiped off as predicted. Dust was brought back into the spacecraft, and was even inhaled by astronauts. This is a major health hazard. Atmospheric storms and other events can also cause dust to coat surfaces of spacecraft. This can cause abrasive damage to the craft. The coating can also reduce the effectiveness of thermal insulation and solar panels.' A group of engineers at Kennedy Space Center's Electrostatics and Surface Physics Laboratory have developed a new technology, called the Electrodynamic Dust Shield, to help alleviate these problems. It is based off of the electric curtain concept developed at NASA in 1967. "The EDS is an active dust mitigation technology that uses traveling electric fields to transport electrostatically charged dust particles along surfaces. To generate the traveling electric fields, the EDS consists of a multilayer dielectric coating with an embedded thin electrode grid

  16. Fuel Cell Demonstration Program

    Energy Technology Data Exchange (ETDEWEB)

    Gerald Brun

    2006-09-15

    In an effort to promote clean energy projects and aid in the commercialization of new fuel cell technologies the Long Island Power Authority (LIPA) initiated a Fuel Cell Demonstration Program in 1999 with six month deployments of Proton Exchange Membrane (PEM) non-commercial Beta model systems at partnering sites throughout Long Island. These projects facilitated significant developments in the technology, providing operating experience that allowed the manufacturer to produce fuel cells that were half the size of the Beta units and suitable for outdoor installations. In 2001, LIPA embarked on a large-scale effort to identify and develop measures that could improve the reliability and performance of future fuel cell technologies for electric utility applications and the concept to establish a fuel cell farm (Farm) of 75 units was developed. By the end of October of 2001, 75 Lorax 2.0 fuel cells had been installed at the West Babylon substation on Long Island, making it the first fuel cell demonstration of its kind and size anywhere in the world at the time. Designed to help LIPA study the feasibility of using fuel cells to operate in parallel with LIPA's electric grid system, the Farm operated 120 fuel cells over its lifetime of over 3 years including 3 generations of Plug Power fuel cells (Lorax 2.0, Lorax 3.0, Lorax 4.5). Of these 120 fuel cells, 20 Lorax 3.0 units operated under this Award from June 2002 to September 2004. In parallel with the operation of the Farm, LIPA recruited government and commercial/industrial customers to demonstrate fuel cells as on-site distributed generation. From December 2002 to February 2005, 17 fuel cells were tested and monitored at various customer sites throughout Long Island. The 37 fuel cells operated under this Award produced a total of 712,635 kWh. As fuel cell technology became more mature, performance improvements included a 1% increase in system efficiency. Including equipment, design, fuel, maintenance

  17. Fusion-power demonstration

    International Nuclear Information System (INIS)

    Henning, C.D.; Logan, B.G.; Carlson, G.A.; Neef, W.S.; Moir, R.W.; Campbell, R.B.; Botwin, R.; Clarkson, I.R.; Carpenter, T.J.

    1983-01-01

    As a satellite to the MARS (Mirror Advanced Reactor Study) a smaller, near-term device has been scoped, called the FPD (Fusion Power Demonstration). Envisioned as the next logical step toward a power reactor, it would advance the mirror fusion program beyond MFTF-B and provide an intermediate step toward commercial fusion power. Breakeven net electric power capability would be the goal such that no net utility power would be required to sustain the operation. A phased implementation is envisioned, with a deuterium checkout first to verify the plasma systems before significant neutron activation has occurred. Major tritium-related facilities would be installed with the second phase to produce sufficient fusion power to supply the recirculating power to maintain the neutral beams, ECRH, magnets and other auxiliary equipment

  18. Spent fuel pyroprocessing demonstration

    International Nuclear Information System (INIS)

    McFarlane, L.F.; Lineberry, M.J.

    1995-01-01

    A major element of the shutdown of the US liquid metal reactor development program is managing the sodium-bonded spent metallic fuel from the Experimental Breeder Reactor-II to meet US environmental laws. Argonne National Laboratory has refurbished and equipped an existing hot cell facility for treating the spent fuel by a high-temperature electrochemical process commonly called pyroprocessing. Four products will be produced for storage and disposal. Two high-level waste forms will be produced and qualified for disposal of the fission and activation products. Uranium and transuranium alloys will be produced for storage pending a decision by the US Department of Energy on the fate of its plutonium and enriched uranium. Together these activities will demonstrate a unique electrochemical treatment technology for spent nuclear fuel. This technology potentially has significant economic and technical advantages over either conventional reprocessing or direct disposal as a high-level waste option

  19. Industrial demonstration trials

    International Nuclear Information System (INIS)

    Gelee, M.; Fabre, C.; Villepoix, R. de; Fra, J.; Le Foulgoc, L.; Morel, Y.; Querite, P.; Roques, R.

    1975-01-01

    Prototypes of the plant components, meeting the specifications set by the process and built by industrial firms in collaboration with the supervisor and the C.E.A., are subjected to trial runs on the UF 6 test bench of the Pierrelatte testing zone. These items of equipment (diffuser, compressor, exchanger) are placed in an industrial operation context very similar to that of an enrichment plant. Their performance is measured within a broad region around the working point and their reliability observed over periods up to several tens of thousands of hours. Between 1969 and 1973 six industrial demonstration test benches have been built, marking the stages in the technical preparation of the 1973 file on the basis of which the decision of building was taken by Eurodif [fr

  20. Fusion Power Demonstration III

    International Nuclear Information System (INIS)

    Lee, J.D.

    1985-07-01

    This is the third in the series of reports covering the Fusion Power Demonstration (FPD) design study. This volume considers the FPD-III configuration that incorporates an octopole end plug. As compared with the quadrupole end-plugged designs of FPD-I and FPD-II, this octopole configuration reduces the number of end cell magnets and shortens the minimum ignition length of the central cell. The end-cell plasma length is also reduced, which in turn reduces the size and cost of the end cell magnets and shielding. As a contiuation in the series of documents covering the FPD, this report does not stand alone as a design description of FPD-III. Design details of FPD-III subsystems that do not differ significantly from those of the FPD-II configuration are not duplicated in this report

  1. Fusion power demonstration

    International Nuclear Information System (INIS)

    Henning, C.D.; Logan, B.G.

    1983-01-01

    As a satellite to the MARS (Mirror Advanced Reactor Study) a smaller, near-term device has been scoped, called the FPD (Fusion Power Demonstration). Envisioned as the next logical step toward a power reactor, it would advance the mirror fusion program beyond MFTF-B and provide an intermediate step toward commercial fusion power. Breakeven net electric power capability would be the goal such that no net utility power would be required to sustain the operation. A phased implementation is envisioned, with a deuterium checkout first to verify the plasma systems before significant neutron activation has occurred. Major tritium-related facilities would be installed with the second phase to produce sufficient fusion power to supply the recirculating power to maintain the neutral beams, ECRH, magnets and other auxiliary equipment

  2. Dynamic wall demonstration project

    Energy Technology Data Exchange (ETDEWEB)

    Nakatsui, L.; Mayhew, W.

    1990-12-01

    The dynamic wall concept is a ventilation strategy that can be applied to a single family dwelling. With suitable construction, outside air can be admitted through the exterior walls of the house to the interior space to function as ventilation air. The construction and performance monitoring of a demonstration house built to test the dynamic wall concept in Sherwood Park, Alberta, is described. The project had the objectives of demonstrating and assessing the construction methods; determining the cost-effectiveness of the concept in Alberta; analyzing the operation of the dynamic wall system; and determining how other components and systems in the house interact with the dynamic wall. The exterior wall construction consisted of vinyl siding, spun-bonded polyolefin-backed (SBPO) rigid fiberglass sheathing, 38 mm by 89 mm framing, fiberglass batt insulation and 12.7 mm drywall. The mechanical system was designed to operate in the dynamic (negative pressure) mode, however flexibility was provided to allow operation in the static (balanced pressure) mode to permit monitoring of the walls as if they were in a conventional house. The house was monitored by an extensive computerized monitoring system. Dynamic wall operation was dependent on pressure and temperature differentials between indoor and outdoor as well as wind speed and direction. The degree of heat gain was found to be ca 74% of the indoor-outdoor temperature differential. Temperature of incoming dynamic air was significantly affected by solar radiation and measurement of indoor air pollutants found no significant levels. 4 refs., 34 figs., 11 tabs.

  3. Latitudinal and radial variation of >2 GeV/n protons and alpha-particles at solar maximum: ULYSSES COSPIN/KET and neutron monitor network observations

    Directory of Open Access Journals (Sweden)

    A. V. Belov

    2003-06-01

    Full Text Available Ulysses, launched in October 1990, began its second out-of-ecliptic orbit in September 1997. In 2000/2001 the spacecraft passed from the south to the north polar regions of the Sun in the inner heliosphere. In contrast to the first rapid pole to pole passage in 1994/1995 close to solar minimum, Ulysses experiences now solar maximum conditions. The Kiel Electron Telescope (KET measures also protons and alpha-particles in the energy range from 5 MeV/n to >2 GeV/n. To derive radial and latitudinal gradients for >2 GeV/n protons and alpha-particles, data from the Chicago instrument on board IMP-8 and the neutron monitor network have been used to determine the corresponding time profiles at Earth. We obtain a spatial distribution at solar maximum which differs greatly from the solar minimum distribution. A steady-state approximation, which was characterized by a small radial and significant latitudinal gradient at solar minimum, was interchanged with a highly variable one with a large radial and a small – consistent with zero – latitudinal gradient. A significant deviation from a spherically symmetric cosmic ray distribution following the reversal of the solar magnetic field in 2000/2001 has not been observed yet. A small deviation has only been observed at northern polar regions, showing an excess of particles instead of the expected depression. This indicates that the reconfiguration of the heliospheric magnetic field, caused by the reappearance of the northern polar coronal hole, starts dominating the modulation of galactic cosmic rays already at solar maximum.Key words. Interplanetary physics (cosmic rays; energetic particles – Space plasma physics (charged particle motion and acceleration

  4. A Demonstration of Lusail

    KAUST Repository

    Mansour, Essam; Abdelaziz, Ibrahim; Ouzzani, Mourad; Aboulnaga, Ashraf; Kalnis, Panos

    2017-01-01

    There has been a proliferation of datasets available as interlinked RDF data accessible through SPARQL endpoints. This has led to the emergence of various applications in life science, distributed social networks, and Internet of Things that need to integrate data from multiple endpoints. We will demonstrate Lusail; a system that supports the need of emerging applications to access tens to hundreds of geo-distributed datasets. Lusail is a geo-distributed graph engine for querying linked RDF data. Lusail delivers outstanding performance using (i) a novel locality-aware query decomposition technique that minimizes the intermediate data to be accessed by the subqueries, and (ii) selectivityawareness and parallel query execution to reduce network latency and to increase parallelism. During the demo, the audience will be able to query actually deployed RDF endpoints as well as large synthetic and real benchmarks that we have deployed in the public cloud. The demo will also show that Lusail outperforms state-of-the-art systems by orders of magnitude in terms of scalability and response time.

  5. A Demonstration of Lusail

    KAUST Repository

    Mansour, Essam

    2017-05-10

    There has been a proliferation of datasets available as interlinked RDF data accessible through SPARQL endpoints. This has led to the emergence of various applications in life science, distributed social networks, and Internet of Things that need to integrate data from multiple endpoints. We will demonstrate Lusail; a system that supports the need of emerging applications to access tens to hundreds of geo-distributed datasets. Lusail is a geo-distributed graph engine for querying linked RDF data. Lusail delivers outstanding performance using (i) a novel locality-aware query decomposition technique that minimizes the intermediate data to be accessed by the subqueries, and (ii) selectivityawareness and parallel query execution to reduce network latency and to increase parallelism. During the demo, the audience will be able to query actually deployed RDF endpoints as well as large synthetic and real benchmarks that we have deployed in the public cloud. The demo will also show that Lusail outperforms state-of-the-art systems by orders of magnitude in terms of scalability and response time.

  6. Demonstration exercise 'Cavtat 09'

    International Nuclear Information System (INIS)

    Trut, D.

    2009-01-01

    The demonstration exercise is to show a terrorist attack in urban area resulting in a certain number of injured people. On 7th April 2009 a terrorist group HAL 9000 is in Cavtat and set up an explosive devices with chemical reagents in several spots with intention to activate them and cause great number of victims. On the same day, in area of the Cavtat Croatia Hotel, which is hosting the world CBMTS Congress, Cavtat Police Station notice several masked persons, in escapement. Hotel personnel alerted the County 112 Center about noticed devices placed by chlorine dioxide tanks, for water conditioning. Intervention police came to block entrance to this area and evacuate hotel's guests and congress members. An explosion and fire occurs from where the position of water-conditioning plant and chlorine dioxide tank. The 112 Center alarms fire-fighters for fight fire and decontamination action and HAZMAT Civil Support Team from Georgia (participated the congress). In the meantime, guests have been instructed not to leave their rooms and to hermetically close doors and windows with available material to keep away potential toxic fume. Decision makers form the County Protection and Rescue Headquarters monitors the situation till the end of alert for the population in the area of Cavtat.(author)

  7. Tidd PFBC demonstration project

    Energy Technology Data Exchange (ETDEWEB)

    Marrocco, M. [American Electric Power, Columbus, OH (United States)

    1997-12-31

    The Tidd project was one of the first joint government-industry ventures to be approved by the US Department of Energy (DOE) in its Clean Coal Technology Program. In March 1987, DOE signed an agreement with the Ohio Power Company, a subsidiary of American Electric Power, to refurbish the then-idle Tidd plant on the banks of the Ohio River with advanced pressurized fluidized bed technology. Testing ended after 49 months of operation, 100 individual tests, and the generation of more than 500,000 megawatt-hours of electricity. The demonstration plant has met its objectives. The project showed that more than 95 percent of sulfur dioxide pollutants could be removed inside the advanced boiler using the advanced combustion technology, giving future power plants an attractive alternative to expensive, add-on scrubber technology. In addition to its sulfur removal effectiveness, the plant`s sustained periods of steady-state operation boosted its availability significantly above design projections, heightening confidence that pressurized fluidized bed technology will be a reliable, baseload technology for future power plants. The technology also controlled the release of nitrogen oxides to levels well below the allowable limits set by federal air quality standards. It also produced a dry waste product that is much easier to handle than wastes from conventional power plants and will likely have commercial value when produced by future power plants.

  8. Osmolality and non-structural carbohydrate composition in the secondary phloem of trees across a latitudinal gradient in Europe

    Directory of Open Access Journals (Sweden)

    Anna eLintunen

    2016-06-01

    Full Text Available Phloem osmolality and its components are involved in basic cell metabolism, cell growth, and in various physiological processes including the ability of living cells to withstand drought and frost. Osmolality and sugar composition responses to environmental stresses have been extensively studied for leaves, but less for the secondary phloem of plant stems and branches. Leaf osmotic concentration and the share of pinitol and raffinose among soluble sugars increase with increasing drought or cold stress, and osmotic concentration is adjusted with osmoregulation. We hypothesize that similar responses occur in the secondary phloem of branches. We collected living bark samples from branches of adult Pinus sylvestris, Picea abies, Betula pendula and Populus tremula trees across Europe, from boreal Northern Finland to Mediterranean Portugal. In all studied species, the observed variation in phloem osmolality was mainly driven by variation in phloem water content, while tissue solute content was rather constant across regions. Osmoregulation, in which osmolality is controlled by variable tissue solute content, was stronger for Betula and Populus in comparison to the evergreen conifers. Osmolality was lowest in mid-latitude region, and from there increased by 37% towards northern Europe and 38% towards southern Europe due to low phloem water content in these regions. The ratio of raffinose to all soluble sugars was negligible at mid-latitudes and increased towards north and south, reflecting its role in cold and drought tolerance. For pinitol, another sugar known for contributing to stress tolerance, no such latitudinal pattern was observed. The proportion of sucrose was remarkably low and that of hexoses (i.e. glucose and fructose high at mid-latitudes. The ratio of starch to all non-structural carbohydrates increased towards the northern latitudes in agreement with the build-up of osmotically inactive C reservoir that can be converted into soluble

  9. Carbon isotope evidence for the latitudinal distribution and wind speed dependence of the air-sea gas transfer velocity

    International Nuclear Information System (INIS)

    Krakauer, Nir Y.

    2006-01-01

    The air-sea gas transfer velocity is an important determinant of the exchange of gases, including CO 2 , between the atmosphere and ocean, but the magnitude of the transfer velocity and what factors control it remains poorly known. Here, we use oceanic and atmospheric observations of 14 C and 13 C to constrain the global mean gas transfer velocity as well as the exponent of its wind speed dependence, utilizing the distinct signatures left by the air-sea exchange of 14 CO 2 and 13 CO 2 . While the atmosphere and ocean inventories of 14 CO 2 and 13 CO 2 constrain the mean gas transfer velocity, the latitudinal pattern in the atmospheric and oceanic 14 C and 13 C distributions contain information about the wind speed dependence. We computed the uptake of bomb 14 C by the ocean for different transfer velocity patterns using pulse response functions from an ocean general circulation model, and evaluated the match between the predicted bomb 14 C concentrations and observationally based estimates for the 1970s-1990s. Using a wind speed climatology based on satellite measurements, we solved either for the best-fit global relationship between gas exchange and mean wind speed or for the mean gas transfer velocity over each of 11 ocean regions. We also compared the predicted consequences of different gas exchange relationships on the rate of change and interhemisphere gradient of 14 C in atmospheric CO 2 with tree-ring and atmospheric measurements. Our results suggest that globally, the dependence of the air-sea gas transfer velocity on wind speed is close to linear, with an exponent of 0.5 ± 0.4, and that the global mean gas transfer velocity at a Schmidt number of 660 is 20 ± 3 cm/hr, similar to the results of previous analyses. We find that the air-sea flux of 13 C estimated from atmosphere and ocean observations also suggests a lower than quadratic dependence of gas exchange on wind speed

  10. Multi-source analysis reveals latitudinal and altitudinal shifts in range of Ixodes ricinus at its northern distribution limit

    Directory of Open Access Journals (Sweden)

    Kristoffersen Anja B

    2011-05-01

    Full Text Available Abstract Background There is increasing evidence for a latitudinal and altitudinal shift in the distribution range of Ixodes ricinus. The reported incidence of tick-borne disease in humans is on the rise in many European countries and has raised political concern and attracted media attention. It is disputed which factors are responsible for these trends, though many ascribe shifts in distribution range to climate changes. Any possible climate effect would be most easily noticeable close to the tick's geographical distribution limits. In Norway- being the northern limit of this species in Europe- no documentation of changes in range has been published. The objectives of this study were to describe the distribution of I. ricinus in Norway and to evaluate if any range shifts have occurred relative to historical descriptions. Methods Multiple data sources - such as tick-sighting reports from veterinarians, hunters, and the general public - and surveillance of human and animal tick-borne diseases were compared to describe the present distribution of I. ricinus in Norway. Correlation between data sources and visual comparison of maps revealed spatial consistency. In order to identify the main spatial pattern of tick abundance, a principal component analysis (PCA was used to obtain a weighted mean of four data sources. The weighted mean explained 67% of the variation of the data sources covering Norway's 430 municipalities and was used to depict the present distribution of I. ricinus. To evaluate if any geographical range shift has occurred in recent decades, the present distribution was compared to historical data from 1943 and 1983. Results Tick-borne disease and/or observations of I. ricinus was reported in municipalities up to an altitude of 583 metres above sea level (MASL and is now present in coastal municipalities north to approximately 69°N. Conclusion I. ricinus is currently found further north and at higher altitudes than described in

  11. New MR pulse sequence

    International Nuclear Information System (INIS)

    Harms, S.E.; Flamig, D.P.; Griffey, R.H.

    1990-01-01

    This paper describes a method for fat suppression for three-dimensional MR imaging. The FATS (fat-suppressed acquisition with echo time shortened) sequence employs a pair of opposing adiabatic half-passage RF pulses tuned on fat resonance. The imaging parameters are as follows: TR, 20 msec; TE, 21.7-3.2 msec; 1,024 x 128 x 128 acquired matrix; imaging time, approximately 11 minutes. A series of 54 examinations were performed. Excellent fat suppression with water excitation is achieved in all cases. The orbital images demonstrate superior resolution of small orbital lesions. The high signal-to-noise ratio (SNR) in cranial studies demonstrates excellent petrous bone and internal auditory canal anatomy

  12. Diversidade dos Belytinae (Hymenoptera: Diaprioidea: Diapriidae) ao longo de um gradiente latitudinal de Mata Atlântica Ombrófila Densa

    OpenAIRE

    Alex Leite Quadros

    2015-01-01

    Os principais objetivos deste trabalho foram conhecer a distribuição da riqueza dos Hymenoptera parasitoides Diapriidae Belytinae ao longo de um gradiente latitudinal da Mata Atlântica e explicar as causas do padrão de riqueza encontrado por comparação com os padrões descritos para outros grupos. Os Belytinae exercem papel chave na regulação natural de populações de muitas espécies de Mycetophilidae e Sciaridae (Diptera) e o conhecimento sobre a diversidade desta subfamília no bioma Mata Atlâ...

  13. Patrones de diversidad de aves a lo largo de un gradiente latitudinal de bosques ribereños del río Paraná medio, Argentina

    OpenAIRE

    Berduc, Alfredo; Lorenzón, Rodrigo Ezequiel; Beltzer, Adolfo Héctor

    2015-01-01

    Se estudió la variación de la riqueza de especies (diversidad alfa), la diversidad beta, la abundancia y la equidad de ensambles de aves a lo largo de un gradiente latitudinal de 500 km de bosques ribereños. Se muestrearon 5 localidades ubicadas en dirección norte-sur mediante una técnica mixta: transectos y puntos de conteo. La riqueza de especies decreció con el incremento de la latitud, reproduciendo el patrón de la riqueza regional informado en estudios previos. Los resultados apoyaron la...

  14. Kinesthetic Transverse Wave Demonstration

    Science.gov (United States)

    Pantidos, Panagiotis; Patapis, Stamatis

    2005-09-01

    This is a variation on the String and Sticky Tape demonstration "The Wave Game," suggested by Ron Edge. A group of students stand side by side, each one holding a card chest high with both hands. The teacher cues the first student to begin raising and lowering his card. When he starts lowering his card, the next student begins to raise his. As succeeding students move their cards up and down, a wave such as that shown in the figure is produced. To facilitate the process, students' motions were synchronized with the ticks of a metronome (without such synchronization it was nearly impossible to generate a satisfactory wave). Our waves typically had a frequency of about 1 Hz and a wavelength of around 3 m. We videotaped the activity so that the students could analyze the motions. The (17-year-old) students had not received any prior instruction regarding wave motion and did not know beforehand the nature of the exercise they were about to carry out. During the activity they were asked what a transverse wave is. Most of them quickly realized, without teacher input, that while the wave propagated horizontally, the only motion of the transmitting medium (them) was vertical. They located the equilibrium points of the oscillations, the crests and troughs of the waves, and identified the wavelength. The teacher defined for them the period of the oscillations of the motion of a card to be the total time for one cycle. The students measured this time and then several asserted that it was the same as the wave period. Knowing the length of the waves and the number of waves per second, the next step can easily be to find the wave speed.

  15. Shotgun protein sequencing.

    Energy Technology Data Exchange (ETDEWEB)

    Faulon, Jean-Loup Michel; Heffelfinger, Grant S.

    2009-06-01

    A novel experimental and computational technique based on multiple enzymatic digestion of a protein or protein mixture that reconstructs protein sequences from sequences of overlapping peptides is described in this SAND report. This approach, analogous to shotgun sequencing of DNA, is to be used to sequence alternative spliced proteins, to identify post-translational modifications, and to sequence genetically engineered proteins.

  16. Multimodal sequence learning.

    Science.gov (United States)

    Kemény, Ferenc; Meier, Beat

    2016-02-01

    While sequence learning research models complex phenomena, previous studies have mostly focused on unimodal sequences. The goal of the current experiment is to put implicit sequence learning into a multimodal context: to test whether it can operate across different modalities. We used the Task Sequence Learning paradigm to test whether sequence learning varies across modalities, and whether participants are able to learn multimodal sequences. Our results show that implicit sequence learning is very similar regardless of the source modality. However, the presence of correlated task and response sequences was required for learning to take place. The experiment provides new evidence for implicit sequence learning of abstract conceptual representations. In general, the results suggest that correlated sequences are necessary for implicit sequence learning to occur. Moreover, they show that elements from different modalities can be automatically integrated into one unitary multimodal sequence. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Sequence Read Archive (SRA)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Sequence Read Archive (SRA) stores raw sequencing data from the next generation of sequencing platforms including Roche 454 GS System®, Illumina Genome...

  18. Broad-scale latitudinal variation in female reproductive success contributes to the maintenance of a geographic range boundary in bagworms (Lepidoptera: Psychidae.

    Directory of Open Access Journals (Sweden)

    Marc Rhainds

    Full Text Available BACKGROUND: Geographic range limits and the factors structuring them are of great interest to biologists, in part because of concerns about how global change may shift range boundaries. However, scientists lack strong mechanistic understanding of the factors that set geographic range limits in empirical systems, especially in animals. METHODOLOGY/PRINCIPAL FINDINGS: Across dozens of populations spread over six degrees of latitude in the American Midwest, female mating success of the evergreen bagworm Thyridopteryx ephemeraeformis (Lepidoptera: Psychidae declines from ∼100% to ∼0% near the edge of the species range. When coupled with additional latitudinal declines in fecundity and in egg and pupal survivorship, a spatial gradient of bagworm reproductive success emerges. This gradient is associated with a progressive decline in local abundance and an increased risk of local population extinction, up to a latitudinal threshold where extremely low female fitness meshes spatially with the species' geographic range boundary. CONCLUSIONS/SIGNIFICANCE: The reduction in fitness of female bagworms near the geographic range limit, which concords with the abundant centre hypothesis from biogeography, provides a concrete, empirical example of how an Allee effect (increased pre-reproductive mortality of females in sparsely populated areas may interact with other demographic factors to induce a geographic range limit.

  19. Diurnal, seasonal and latitudinal variations of electron temperature measured by the SROSS C2 satellite at 500 km altitude and comparison with the IRI

    Directory of Open Access Journals (Sweden)

    P. K. Bhuyan

    2002-06-01

    Full Text Available The diurnal, seasonal and latitudinal variations of electron temperature Te, measured by the SROSS C2 satellite at equatorial and the low-latitudes during the low solar activity period of 1995–1997 are investigated. The average height of the satellite was ~ 500 km and it covered the latitude belt of –31° to 34° and the longitude range of 40°–100°. Te varies between 700–800 K during night-time (20:00–04:00 LT, rises sharply during sunrise (04:00–06:00 LT to reach a level of ~ 3500 K within a couple of hours and then falls between 07:00–10:00 LT to a daytime average value of ~ 1600 K. A secondary maximum is observed around 16:00–18:00 LT in summer. Latitudinal gradients in Te have been observed during the morning enhancement and daytime hours. Comparison of measured and International Reference Ionosphere (IRI predicted electron temperature reveals that the IRI predicts nighttime Te well within ~ 100 K of observation, but at other local times, the predicted Te is less than that measured in all seasons.Key words. Ionosphere, equatorial ionosphere, plasma temperature, and density

  20. Analysis of the Latitudinal Variability of Tropospheric Ozone in the Arctic Using the Large Number of Aircraft and Ozonesonde Observations in Early Summer 2008

    Science.gov (United States)

    Ancellet, Gerard; Daskalakis, Nikos; Raut, Jean Christophe; Quennehen, Boris; Ravetta, Francois; Hair, Jonathan; Tarasick, David; Schlager, Hans; Weinheimer, Andrew J.; Thompson, Anne M.; hide

    2016-01-01

    The goal of the paper are to: (1) present tropospheric ozone (O3) climatologies in summer 2008 based on a large amount of measurements, during the International Polar Year when the Polar Study using Aircraft, Remote Sensing, Surface Measurements, and Models of Climate Chemistry, Aerosols, and Transport (POLARCAT) campaigns were conducted (2) investigate the processes that determine O3 concentrations in two different regions (Canada and Greenland) that were thoroughly studied using measurements from 3 aircraft and 7 ozonesonde stations. This paper provides an integrated analysis of these observations and the discussion of the latitudinal and vertical variability of tropospheric ozone north of 55oN during this period is performed using a regional model (WFR-Chem). Ozone, CO and potential vorticity (PV) distributions are extracted from the simulation at the measurement locations. The model is able to reproduce the O3 latitudinal and vertical variability but a negative O3 bias of 6-15 ppbv is found in the free troposphere over 4 km, especially over Canada. Ozone average concentrations are of the order of 65 ppbv at altitudes above 4 km both over Canada and Greenland, while they are less than 50 ppbv in the lower troposphere. The relative influence of stratosphere-troposphere exchange (STE) and of ozone production related to the local biomass burning (BB) emissions is discussed using differences between average values of O3, CO and PV for Southern and Northern Canada or Greenland and two vertical ranges in the troposphere: 0-4 km and 4-8 km. For Canada, the model CO distribution and the weak correlation (less than 30%) of O3 and PV suggests that stratosphere troposphere exchange (STE) is not the major contribution to average tropospheric ozone at latitudes less than 70 deg N, due to the fact that local biomass burning (BB) emissions were significant during the 2008 summer period. Conversely over Greenland, significant STE is found according to the better O3 versus PV

  1. ROBOT LEARNING OF OBJECT MANIPULATION TASK ACTIONS FROM HUMAN DEMONSTRATIONS

    Directory of Open Access Journals (Sweden)

    Maria Kyrarini

    2017-08-01

    Full Text Available Robot learning from demonstration is a method which enables robots to learn in a similar way as humans. In this paper, a framework that enables robots to learn from multiple human demonstrations via kinesthetic teaching is presented. The subject of learning is a high-level sequence of actions, as well as the low-level trajectories necessary to be followed by the robot to perform the object manipulation task. The multiple human demonstrations are recorded and only the most similar demonstrations are selected for robot learning. The high-level learning module identifies the sequence of actions of the demonstrated task. Using Dynamic Time Warping (DTW and Gaussian Mixture Model (GMM, the model of demonstrated trajectories is learned. The learned trajectory is generated by Gaussian mixture regression (GMR from the learned Gaussian mixture model.  In online working phase, the sequence of actions is identified and experimental results show that the robot performs the learned task successfully.

  2. Information Integration Technology Demonstration (IITD)

    National Research Council Canada - National Science Library

    Loe, Richard

    2001-01-01

    The objectives of the Information Integration Technology Demonstration (IITD) were to investigate, design a software architecture and demonstrate a capability to display intelligence data from multiple disciplines...

  3. Adaptations to “Thermal Time” Constraints in Papilio: Latitudinal and Local Size Clines Differ in Response to Regional Climate Change

    Science.gov (United States)

    Scriber, J. Mark; Elliot, Ben; Maher, Emily; McGuire, Molly; Niblack, Marjie

    2014-01-01

    Adaptations to “thermal time” (=Degree-day) constraints on developmental rates and voltinism for North American tiger swallowtail butterflies involve most life stages, and at higher latitudes include: smaller pupae/adults; larger eggs; oviposition on most nutritious larval host plants; earlier spring adult emergences; faster larval growth and shorter molting durations at lower temperatures. Here we report on forewing sizes through 30 years for both the northern univoltine P. canadensis (with obligate diapause) from the Great Lakes historical hybrid zone northward to central Alaska (65° N latitude), and the multivoltine, P. glaucus from this hybrid zone southward to central Florida (27° N latitude). Despite recent climate warming, no increases in mean forewing lengths of P. glaucus were observed at any major collection location (FL to MI) from the 1980s to 2013 across this long latitudinal transect (which reflects the “converse of Bergmann’s size Rule”, with smaller females at higher latitudes). Unlike lower latitudes, the Alaska, Ontonogon, and Chippewa/Mackinac locations (for P. canadensis) showed no significant increases in D-day accumulations, which could explain lack of size change in these northernmost locations. As a result of 3–4 decades of empirical data from major collection sites across these latitudinal clines of North America, a general “voltinism/size/D-day” model is presented, which more closely predicts female size based on D-day accumulations, than does latitude. However, local “climatic cold pockets” in northern Michigan and Wisconsin historically appeared to exert especially strong size constraints on female forewing lengths, but forewing lengths quickly increased with local summer warming during the recent decade, especially near the warming edges of the cold pockets. Results of fine-scale analyses of these “cold pockets” are in contrast to non-significant changes for other Papilio populations seen across the latitudinal

  4. Nonparametric combinatorial sequence models.

    Science.gov (United States)

    Wauthier, Fabian L; Jordan, Michael I; Jojic, Nebojsa

    2011-11-01

    This work considers biological sequences that exhibit combinatorial structures in their composition: groups of positions of the aligned sequences are "linked" and covary as one unit across sequences. If multiple such groups exist, complex interactions can emerge between them. Sequences of this kind arise frequently in biology but methodologies for analyzing them are still being developed. This article presents a nonparametric prior on sequences which allows combinatorial structures to emerge and which induces a posterior distribution over factorized sequence representations. We carry out experiments on three biological sequence families which indicate that combinatorial structures are indeed present and that combinatorial sequence models can more succinctly describe them than simpler mixture models. We conclude with an application to MHC binding prediction which highlights the utility of the posterior distribution over sequence representations induced by the prior. By integrating out the posterior, our method compares favorably to leading binding predictors.

  5. Explaining the harmonic sequence paradox.

    Science.gov (United States)

    Schmidt, Ulrich; Zimper, Alexander

    2012-05-01

    According to the harmonic sequence paradox, an expected utility decision maker's willingness to pay for a gamble whose expected payoffs evolve according to the harmonic series is finite if and only if his marginal utility of additional income becomes zero for rather low payoff levels. Since the assumption of zero marginal utility is implausible for finite payoff levels, expected utility theory - as well as its standard generalizations such as cumulative prospect theory - are apparently unable to explain a finite willingness to pay. This paper presents first an experimental study of the harmonic sequence paradox. Additionally, it demonstrates that the theoretical argument of the harmonic sequence paradox only applies to time-patient decision makers, whereas the paradox is easily avoided if time-impatience is introduced. ©2011 The British Psychological Society.

  6. Lunar fingerprints in the modulated incoming solar radiation: In situ insolation and latitudinal insolation gradients as two important interpretative metrics for paleoclimatic data records and theoretical climate modeling

    Science.gov (United States)

    Cionco, Rodolfo Gustavo; Valentini, José Ernesto; Quaranta, Nancy Esther; Soon, Willie W.-H.

    2018-01-01

    We present a new set of solar radiation forcing that now incorporated not only the gravitational perturbation of the Sun-Earth-Moon geometrical orbits but also the intrinsic solar magnetic modulation of the total solar irradiance (TSI). This new dataset, covering the past 2000 years as well as a forward projection for about 100 years based on recent result by Velasco-Herrera et al. (2015), should provide a realistic basis to examine and evaluate the role of external solar forcing on Earth climate on decadal, multidecadal to multicentennial timescales. A second goal of this paper is to propose both in situ insolation forcing variable and the latitudinal insolation gradients (LIG) as two key metrics that are subjected to a deterministic modulation by lunar nodal cycle which are often confused with tidal forcing impacts as assumed and interpreted in previous studies of instrumental and paleoclimatic records. Our new results and datasets are made publicly available for all at PANGAEA site.

  7. Genome Sequence Databases (Overview): Sequencing and Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Lapidus, Alla L.

    2009-01-01

    From the date its role in heredity was discovered, DNA has been generating interest among scientists from different fields of knowledge: physicists have studied the three dimensional structure of the DNA molecule, biologists tried to decode the secrets of life hidden within these long molecules, and technologists invent and improve methods of DNA analysis. The analysis of the nucleotide sequence of DNA occupies a special place among the methods developed. Thanks to the variety of sequencing technologies available, the process of decoding the sequence of genomic DNA (or whole genome sequencing) has become robust and inexpensive. Meanwhile the assembly of whole genome sequences remains a challenging task. In addition to the need to assemble millions of DNA fragments of different length (from 35 bp (Solexa) to 800 bp (Sanger)), great interest in analysis of microbial communities (metagenomes) of different complexities raises new problems and pushes some new requirements for sequence assembly tools to the forefront. The genome assembly process can be divided into two steps: draft assembly and assembly improvement (finishing). Despite the fact that automatically performed assembly (or draft assembly) is capable of covering up to 98% of the genome, in most cases, it still contains incorrectly assembled reads. The error rate of the consensus sequence produced at this stage is about 1/2000 bp. A finished genome represents the genome assembly of much higher accuracy (with no gaps or incorrectly assembled areas) and quality ({approx}1 error/10,000 bp), validated through a number of computer and laboratory experiments.

  8. Buried Waste Integrated Demonstration lessons learned: 1993 technology demonstrations

    International Nuclear Information System (INIS)

    Kostelnik, K.M.; Owens, K.J.

    1994-01-01

    An integrated technology demonstration was conducted by the Buried Waste Integrated Demonstration (BWID) at the Idaho National Engineering Laboratory Cold Test Pit in the summer of 1993. This program and demonstration was sponsored by the US Department of Energy Office of Technology Development. The demonstration included six technologies representing a synergistic system for the characterization and retrieval of a buried hazardous waste site. The integrated technology demonstration proved very successful and a summary of the technical accomplishments is presented. Upon completion of the integrated technology demonstration, cognizant program personnel participated in a lessons learned exercise. This exercise was conducted at the Simplot Decision Support Center at Idaho State University and lessons learned activity captured additional information relative to the integration of technologies for demonstration purposes. This information will be used by BWID to enhance program planning and strengthen future technology demonstrations

  9. Abundance of two Pelagibacter ubique bacteriophage genotypes along a latitudinal transect in the North and South Atlantic Oceans

    Directory of Open Access Journals (Sweden)

    Erin M Eggleston

    2016-09-01

    Full Text Available This study characterizes viral and bacterial dynamics along a latitudinal transect in the Atlantic Ocean from approximately 10N to 40S. Overall viral abundance decreased with depth, on average there were 1.64 ± 0.71 x107 virus like particles (VLPs in surface waters, decreasing to an average of 6.50 ± 2.26 x105 VLPs in Antarctic Bottom Water. This decrease was highly correlated to bacterial abundance. There are six major water masses in the Southern Tropical Atlantic Ocean, and inclusion of water mass, temperature and salinity variables explained a majority of the variation in total viral abundance. Recent discovery of phages infecting bacteria of the SAR11 clade of Alphaproteobacteria (i.e. pelagiphages leads to intriguing questions about the roles they play in shaping epipelagic communities. Viral-size fraction DNA from epipelagic water was used to quantify the abundance of two pelagiphages, using pelagiphage-specific quantitative PCR primers and probes along the transect. We found that HTVC010P, a member of a podoviridae sub-family, was most abundant in surface waters. Copy numbers ranged from an average of 1.03 ± 2.38 x 105 copies ml-1 in surface waters, to 5.79 ± 2.86 x103 in the deep chlorophyll maximum. HTVC008M, a T4-like myovirus, was present in the deep chlorophyll maximum (5.42±2.8x103 copies ml-1 on average, although it was not as highly abundant as HTVC010P in surface waters (6.05±3.01x103 copies ml-1 on average. Interestingly, HTVC008M was only present at a few of the most southern stations, suggesting latitudinal biogeography of SAR11 phages.

  10. Propagation properties of Rossby waves for latitudinal β-plane variations of f and zonal variations of the shallow water speed

    Directory of Open Access Journals (Sweden)

    C. T. Duba

    2012-05-01

    Full Text Available Using the shallow water equations for a rotating layer of fluid, the wave and dispersion equations for Rossby waves are developed for the cases of both the standard β-plane approximation for the latitudinal variation of the Coriolis parameter f and a zonal variation of the shallow water speed. It is well known that the wave normal diagram for the standard (mid-latitude Rossby wave on a β-plane is a circle in wave number (ky,kx space, whose centre is displaced −β/2 ω units along the negative kx axis, and whose radius is less than this displacement, which means that phase propagation is entirely westward. This form of anisotropy (arising from the latitudinal y variation of f, combined with the highly dispersive nature of the wave, gives rise to a group velocity diagram which permits eastward as well as westward propagation. It is shown that the group velocity diagram is an ellipse, whose centre is displaced westward, and whose major and minor axes give the maximum westward, eastward and northward (southward group speeds as functions of the frequency and a parameter m which measures the ratio of the low frequency-long wavelength Rossby wave speed to the shallow water speed. We believe these properties of group velocity diagram have not been elucidated in this way before. We present a similar derivation of the wave normal diagram and its associated group velocity curve for the case of a zonal (x variation of the shallow water speed, which may arise when the depth of an ocean varies zonally from a continental shelf.

  11. Equatorial seawater temperatures and latitudinal temperature gradients during the Middle to Late Jurassic: the stable isotope record of brachiopods and oysters from Gebel Maghara, Egypt

    Science.gov (United States)

    Alberti, Matthias; Fürsich, Franz T.; Abdelhady, Ahmed A.; Andersen, Nils

    2017-04-01

    The Jurassic climate has traditionally been described as equable, warmer than today, with weak latitudinal temperature gradients, and no polar glaciations. This view changed over the last decades with studies pointing to distinct climate fluctuations and the occasional presence of polar ice caps. Most of these temperature reconstructions are based on stable isotope analyses of fossil shells from Europe. Additional data from other parts of the world is slowly completing the picture. Gebel Maghara in the northern Sinai Peninsula of Egypt exposes a thick Jurassic succession. After a phase of terrestrial sedimentation in the Early Jurassic, marine conditions dominated since the end of the Aalenian. The stable isotope (δ18O, δ13C) composition of brachiopod and oyster shells was used to reconstruct seawater temperatures from the Bajocian to the Kimmeridgian at a palaeolatitude of ca. 3°N. Throughout this time interval, temperatures were comparatively constant aorund an average of 25.7°C. Slightly warmer conditions existed in the Early Bathonian ( 27.0°C), while the Kimmeridgian shows the lowest temperatures ( 24.3°C). The seasonality has been reconstructed with the help of high-resolution sampling of two oyster shells and was found to be very low (temperature gradients. During the Middle Jurassic, this gradient was much steeper than previously expected and comparable to today. During the Kimmeridgian, temperatures in Europe were generally warmer leading to weaker latitudinal gradients. Based on currently used estimates for the δ18O value of seawater during the Jurassic, reconstructed water temperatures for localities above the thermocline in Egypt and Europe were mostly lower than Recent sea-surface temperatures. These results improve our understanding of the Jurassic climate and its influence on marine faunal diversity patterns.

  12. Hardware Accelerated Sequence Alignment with Traceback

    Directory of Open Access Journals (Sweden)

    Scott Lloyd

    2009-01-01

    in a timely manner. Known methods to accelerate alignment on reconfigurable hardware only address sequence comparison, limit the sequence length, or exhibit memory and I/O bottlenecks. A space-efficient, global sequence alignment algorithm and architecture is presented that accelerates the forward scan and traceback in hardware without memory and I/O limitations. With 256 processing elements in FPGA technology, a performance gain over 300 times that of a desktop computer is demonstrated on sequence lengths of 16000. For greater performance, the architecture is scalable to more processing elements.

  13. Long sequence correlation coprocessor

    Science.gov (United States)

    Gage, Douglas W.

    1994-09-01

    A long sequence correlation coprocessor (LSCC) accelerates the bitwise correlation of arbitrarily long digital sequences by calculating in parallel the correlation score for 16, for example, adjacent bit alignments between two binary sequences. The LSCC integrated circuit is incorporated into a computer system with memory storage buffers and a separate general purpose computer processor which serves as its controller. Each of the LSCC's set of sequential counters simultaneously tallies a separate correlation coefficient. During each LSCC clock cycle, computer enable logic associated with each counter compares one bit of a first sequence with one bit of a second sequence to increment the counter if the bits are the same. A shift register assures that the same bit of the first sequence is simultaneously compared to different bits of the second sequence to simultaneously calculate the correlation coefficient by the different counters to represent different alignments of the two sequences.

  14. Roles of repetitive sequences

    Energy Technology Data Exchange (ETDEWEB)

    Bell, G.I.

    1991-12-31

    The DNA of higher eukaryotes contains many repetitive sequences. The study of repetitive sequences is important, not only because many have important biological function, but also because they provide information on genome organization, evolution and dynamics. In this paper, I will first discuss some generic effects that repetitive sequences will have upon genome dynamics and evolution. In particular, it will be shown that repetitive sequences foster recombination among, and turnover of, the elements of a genome. I will then consider some examples of repetitive sequences, notably minisatellite sequences and telomere sequences as examples of tandem repeats, without and with respectively known function, and Alu sequences as an example of interspersed repeats. Some other examples will also be considered in less detail.

  15. Anomaly Detection in Sequences

    Data.gov (United States)

    National Aeronautics and Space Administration — We present a set of novel algorithms which we call sequenceMiner, that detect and characterize anomalies in large sets of high-dimensional symbol sequences that...

  16. DNA sequencing conference, 2

    Energy Technology Data Exchange (ETDEWEB)

    Cook-Deegan, R.M. [Georgetown Univ., Kennedy Inst. of Ethics, Washington, DC (United States); Venter, J.C. [National Inst. of Neurological Disorders and Strokes, Bethesda, MD (United States); Gilbert, W. [Harvard Univ., Cambridge, MA (United States); Mulligan, J. [Stanford Univ., CA (United States); Mansfield, B.K. [Oak Ridge National Lab., TN (United States)

    1991-06-19

    This conference focused on DNA sequencing, genetic linkage mapping, physical mapping, informatics and bioethics. Several were used to study this sequencing and mapping. This article also discusses computer hardware and software aiding in the mapping of genes.

  17. sequenceMiner algorithm

    Data.gov (United States)

    National Aeronautics and Space Administration — Detecting and describing anomalies in large repositories of discrete symbol sequences. sequenceMiner has been open-sourced! Download the file below to try it out....

  18. Integrated Ground Operations Demonstration Units

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall goal of the AES Integrated Ground Operations Demonstration Units (IGODU) project is to demonstrate cost efficient cryogenic operations on a relevant...

  19. Cargo Data Management Demonstration System

    Science.gov (United States)

    1974-02-01

    Delays in receipt and creation of cargo documents are a problem in international trade. The work described demonstrates some of the advantages and capabilities of a computer-based cargo data management system. A demonstration system for data manageme...

  20. Teleoperation for learning by demonstration

    DEFF Research Database (Denmark)

    Kukliński, Kamil; Fischer, Kerstin; Marhenke, Ilka

    2014-01-01

    Learning by demonstration is a useful technique to augment a robot's behavioral inventory, and teleoperation allows lay users to demonstrate novel behaviors intuitively to the robot. In this paper, we compare two modes of teleoperation of an industrial robot, the demonstration by means of a data...... glove and by means of a control object (peg). Experiments with 16 lay users, performing assembly task on the Cranfield benchmark objects, show that the control peg leads to more success, more efficient demonstration and fewer errors....

  1. Helicopter detection and classification demonstrator

    NARCIS (Netherlands)

    Koersel, A.C. van

    2000-01-01

    A technology demonstrator that detects and classifies different helicopter types automatically, was developed at TNO-FEL. The demonstrator is based on a PC, which receives its acoustic input from an all-weather microphone. The demonstrator uses commercial off-the-shelf hardware to digitize the

  2. Targeted assembly of short sequence reads.

    Directory of Open Access Journals (Sweden)

    René L Warren

    Full Text Available As next-generation sequence (NGS production continues to increase, analysis is becoming a significant bottleneck. However, in situations where information is required only for specific sequence variants, it is not necessary to assemble or align whole genome data sets in their entirety. Rather, NGS data sets can be mined for the presence of sequence variants of interest by localized assembly, which is a faster, easier, and more accurate approach. We present TASR, a streamlined assembler that interrogates very large NGS data sets for the presence of specific variants by only considering reads within the sequence space of input target sequences provided by the user. The NGS data set is searched for reads with an exact match to all possible short words within the target sequence, and these reads are then assembled stringently to generate a consensus of the target and flanking sequence. Typically, variants of a particular locus are provided as different target sequences, and the presence of the variant in the data set being interrogated is revealed by a successful assembly outcome. However, TASR can also be used to find unknown sequences that flank a given target. We demonstrate that TASR has utility in finding or confirming genomic mutations, polymorphisms, fusions and integration events. Targeted assembly is a powerful method for interrogating large data sets for the presence of sequence variants of interest. TASR is a fast, flexible and easy to use tool for targeted assembly.

  3. Orbital Express fluid transfer demonstration system

    Science.gov (United States)

    Rotenberger, Scott; SooHoo, David; Abraham, Gabriel

    2008-04-01

    Propellant resupply of orbiting spacecraft is no longer in the realm of high risk development. The recently concluded Orbital Express (OE) mission included a fluid transfer demonstration that operated the hardware and control logic in space, bringing the Technology Readiness Level to a solid TRL 7 (demonstration of a system prototype in an operational environment). Orbital Express (funded by the Defense Advanced Research Projects Agency, DARPA) was launched aboard an Atlas-V rocket on March 9th, 2007. The mission had the objective of demonstrating technologies needed for routine servicing of spacecraft, namely autonomous rendezvous and docking, propellant resupply, and orbital replacement unit transfer. The demonstration system used two spacecraft. A servicing vehicle (ASTRO) performed multiple dockings with the client (NextSat) spacecraft, and performed a variety of propellant transfers in addition to exchanges of a battery and computer. The fluid transfer and propulsion system onboard ASTRO, in addition to providing the six degree-of-freedom (6 DOF) thruster system for rendezvous and docking, demonstrated autonomous transfer of monopropellant hydrazine to or from the NextSat spacecraft 15 times while on orbit. The fluid transfer system aboard the NextSat vehicle was designed to simulate a variety of client systems, including both blowdown pressurization and pressure regulated propulsion systems. The fluid transfer demonstrations started with a low level of autonomy, where ground controllers were allowed to review the status of the demonstration at numerous points before authorizing the next steps to be performed. The final transfers were performed at a full autonomy level where the ground authorized the start of a transfer sequence and then monitored data as the transfer proceeded. The major steps of a fluid transfer included the following: mate of the coupling, leak check of the coupling, venting of the coupling, priming of the coupling, fluid transfer, gauging

  4. Rapid Multiplex Small DNA Sequencing on the MinION Nanopore Sequencing Platform

    Directory of Open Access Journals (Sweden)

    Shan Wei

    2018-05-01

    Full Text Available Real-time sequencing of short DNA reads has a wide variety of clinical and research applications including screening for mutations, target sequences and aneuploidy. We recently demonstrated that MinION, a nanopore-based DNA sequencing device the size of a USB drive, could be used for short-read DNA sequencing. In this study, an ultra-rapid multiplex library preparation and sequencing method for the MinION is presented and applied to accurately test normal diploid and aneuploidy samples’ genomic DNA in under three hours, including library preparation and sequencing. This novel method shows great promise as a clinical diagnostic test for applications requiring rapid short-read DNA sequencing.

  5. Optics Demonstrations Using Cylindrical Lenses

    Science.gov (United States)

    Ivanov, Dragia; Nikolov, Stefan

    2015-01-01

    In this paper we consider the main properties of cylindrical lenses and propose several demonstrational experiments that can be performed with them. Specifically we use simple glasses full of water to demonstrate some basic geometrical optics principles and phenomena. We also present some less standard experiments that can be performed with such…

  6. A Comprehensive General Chemistry Demonstration

    Science.gov (United States)

    Sweeder, Ryan D.; Jeffery, Kathleen A.

    2013-01-01

    This article describes the use of a comprehensive demonstration suitable for a high school or first-year undergraduate introductory chemistry class. The demonstration involves placing a burning candle in a container adjacent to a beaker containing a basic solution with indicator. After adding a lid, the candle will extinguish and the produced…

  7. Development of microsatellite markers using next-generation sequencing for the columnar cactus Echinopsis chiloensis (Cactaceae).

    Science.gov (United States)

    Ossa, Carmen G; Larridon, Isabel; Peralta, Gioconda; Asselman, Pieter; Pérez, Fernanda

    2016-12-01

    The aim of this study was to develop microsatellite markers as a tool to study population structure, genetic diversity and effective population size of Echinopsis chiloensis, an endemic cactus from arid and semiarid regions of Central Chile. We developed 12 polymorphic microsatellite markers for E. chiloensis using next-generation sequencing and tested them in 60 individuals from six sites, covering all the latitudinal range of this species. The number of alleles per locus ranged from 3 to 8, while the observed (Ho) and expected (He) heterozygosity ranged from 0.0 to 0.80 and from 0.10 to 0.76, respectively. We also detected significant differences between sites, with F ST values ranging from 0.05 to 0.29. Microsatellite markers will enable us to estimate genetic diversity and population structure of E. chiloensis in future ecological and phylogeographic studies.

  8. Offsite demonstrations for MWLID technologies

    International Nuclear Information System (INIS)

    Williams, C.; Gruebel, R.

    1995-01-01

    The goal of the Offsite Demonstration Project for Mixed Waste Landfill Integrated Demonstration (MWLID)-developed environmental site characterization and remediation technologies is to facilitate the transfer, use, and commercialization of these technologies to the public and private sector. The meet this goal, the project identified environmental restoration needs of mixed waste and/or hazardous waste landfill owners (Native American, municipal, DOE, and DoD); documenting potential demonstration sites and the contaminants present at each site; assessing the environmental regulations that would effect demonstration activities; and evaluating site suitability for demonstrating MWLID technologies at the tribal and municipal sites identified. Eighteen landfill sites within a 40.2-km radius of Sandia National Laboratories are listed on the CERCLIS Site/Event Listing for the state of New Mexico. Seventeen are not located within DOE or DoD facilities and are potential offsite MWLID technology demonstration sites. Two of the seventeen CERCLIS sites, one on Native American land and one on municipal land, were evaluated and identified as potential candidates for off-site demonstrations of MWLID-developed technologies. Contaminants potentially present on site include chromium waste, household/commercial hazardous waste, volatile organic compounds, and petroleum products. MWLID characterization technologies applicable to these sites include Magnetometer Towed Array, Cross-borehole Electromagnetic Imaging, SitePlanner trademark/PLUME, Hybrid Directional Drilling, Seamist trademark/Vadose Zone Monitoring, Stripping Analyses, and x-ray Fluorescence Spectroscopy for Heavy Metals

  9. Sequencing of chloroplast genome using whole cellular DNA and Solexa sequencing technology

    Directory of Open Access Journals (Sweden)

    Jian eWu

    2012-11-01

    Full Text Available Sequencing of the chloroplast genome using traditional sequencing methods has been difficult because of its size (>120 kb and the complicated procedures required to prepare templates. To explore the feasibility of sequencing the chloroplast genome using DNA extracted from whole cells and Solexa sequencing technology, we sequenced whole cellular DNA isolated from leaves of three Brassica rapa accessions with one lane per accession. In total, 246 Mb, 362Mb, 361 Mb sequence data were generated for the three accessions Chiifu-401-42, Z16 and FT, respectively. Microreads were assembled by reference-guided assembly using the cpDNA sequences of B. rapa, Arabidopsis thaliana, and Nicotiana tabacum. We achieved coverage of more than 99.96% of the cp genome in the three tested accessions using the B. rapa sequence as the reference. When A. thaliana or N. tabacum sequences were used as references, 99.7–99.8% or 95.5–99.7% of the B. rapa chloroplast genome was covered, respectively. These results demonstrated that sequencing of whole cellular DNA isolated from young leaves using the Illumina Genome Analyzer is an efficient method for high-throughput sequencing of chloroplast genome.

  10. Exome sequencing and genetic testing for MODY.

    Directory of Open Access Journals (Sweden)

    Stefan Johansson

    Full Text Available Genetic testing for monogenic diabetes is important for patient care. Given the extensive genetic and clinical heterogeneity of diabetes, exome sequencing might provide additional diagnostic potential when standard Sanger sequencing-based diagnostics is inconclusive.The aim of the study was to examine the performance of exome sequencing for a molecular diagnosis of MODY in patients who have undergone conventional diagnostic sequencing of candidate genes with negative results.We performed exome enrichment followed by high-throughput sequencing in nine patients with suspected MODY. They were Sanger sequencing-negative for mutations in the HNF1A, HNF4A, GCK, HNF1B and INS genes. We excluded common, non-coding and synonymous gene variants, and performed in-depth analysis on filtered sequence variants in a pre-defined set of 111 genes implicated in glucose metabolism.On average, we obtained 45 X median coverage of the entire targeted exome and found 199 rare coding variants per individual. We identified 0-4 rare non-synonymous and nonsense variants per individual in our a priori list of 111 candidate genes. Three of the variants were considered pathogenic (in ABCC8, HNF4A and PPARG, respectively, thus exome sequencing led to a genetic diagnosis in at least three of the nine patients. Approximately 91% of known heterozygous SNPs in the target exomes were detected, but we also found low coverage in some key diabetes genes using our current exome sequencing approach. Novel variants in the genes ARAP1, GLIS3, MADD, NOTCH2 and WFS1 need further investigation to reveal their possible role in diabetes.Our results demonstrate that exome sequencing can improve molecular diagnostics of MODY when used as a complement to Sanger sequencing. However, improvements will be needed, especially concerning coverage, before the full potential of exome sequencing can be realized.

  11. Notional Airspace Operations Demonstration Plan

    Science.gov (United States)

    Trongale, Nicholas A.

    2006-01-01

    The airspace operations demonstration (AOD) is intended to show that the Access 5 Step 1 functional requirements can be met. The demonstration will occur in two phases. The initial on-range phase will be carried out in restricted airspace to demonstrate the cooperative collision avoidance (CCA) functional requirements and to provide risk-reduction for the AOD by allowing the test team to rehearse some elements of the demonstration mission. The CCA system to be used in these flights is based on Automatic Dependent Surveillance-Broadcast (ADS-B) which is a commercially-available system by which airplanes constantly broadcast their current position and altitude to other aircraft and ground resources over a dedicated radio datalink. The final phase will occur in the national airspace (NAS) and will be the formal demonstration of the remainder of the proposed functional requirements. The general objectives of the AOD are as follows: (1) Demonstrate that the UAS can aviate in the NAS (2) Demonstrate that the UAS can navigate in the NAS (3) Demonstrate that the UAS can communicate with the NAS (4) Demonstrate that the UAS can perform selected collision avoidance functions in the NAS (5) Demonstrate that the UAS can evaluate and avoid weather conflicts in the NAS (6) Demonstrate that the UAS can provide adequate command and control in the NAS In addition to the stated objectives, there are a number of goals for the flight demonstration. The demo can be accomplished successfully without achieving these goals, but these goals are to be used as a guideline for preparing for the mission. The goals are: (1) Mission duration of at least 24 hours (2) Loiter over heavy traffic to evaluate the data block issue identified during the Access 5 Airspace Operations Simulations (3) Document the contingency management process and lessons learned (4) Document the coordination process for Ground Control Stations (GCS) handoff (5) Document lessons learned regarding the process of flying in

  12. Nonparametric Inference for Periodic Sequences

    KAUST Repository

    Sun, Ying

    2012-02-01

    This article proposes a nonparametric method for estimating the period and values of a periodic sequence when the data are evenly spaced in time. The period is estimated by a "leave-out-one-cycle" version of cross-validation (CV) and complements the periodogram, a widely used tool for period estimation. The CV method is computationally simple and implicitly penalizes multiples of the smallest period, leading to a "virtually" consistent estimator of integer periods. This estimator is investigated both theoretically and by simulation.We also propose a nonparametric test of the null hypothesis that the data have constantmean against the alternative that the sequence of means is periodic. Finally, our methodology is demonstrated on three well-known time series: the sunspots and lynx trapping data, and the El Niño series of sea surface temperatures. © 2012 American Statistical Association and the American Society for Quality.

  13. Demonstration of Cauchy: Understanding Algebraic

    Directory of Open Access Journals (Sweden)

    T.L. Costa

    2012-11-01

    Full Text Available ABSTRACT: In this study we present some considerations about the End of Course Work undergraduate Full Degree in Mathematics / UFMT, drafted in 2011, and by taking title "A story about Cauchy and Euler's theorem on polyhedra" that gave birth to our research project Master of Education, begun in 2012, on the approaches of Euler's theorem on polyhedra in mathematics textbooks. At work in 2011 presented some considerations about the history of Euler's theorem for polyhedra which focus the demonstration presented by Cauchy (1789-1857, who tries to generalize it, relying on assumptions not observable in Euclidean geometry. Therefore, we seek the accessible literature on the history of mathematics; relate some aspects of the demonstration Cauchy with historical events on the development of mathematics in the nineteenth century, which allowed the acceptance of such a demonstration by mathematicians of his time.Keywords: History of Mathematics. Euler's Theorem on Polyhedra. Demonstration of Cauchy.

  14. CT Demonstration of Caput Medusae

    Science.gov (United States)

    Weber, Edward C.; Vilensky, Joel A.

    2009-01-01

    Maximum intensity and volume rendered CT displays of caput medusae are provided to demonstrate both the anatomy and physiology of this portosystemic shunt associated with portal hypertension. (Contains 2 figures.)

  15. Fuel Gas Demonstration Plant Program. Volume I. Demonstration plant

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    The objective of this project is for Babcock Contractors Inc. (BCI) to provide process designs, and gasifier retort design for a fuel gas demonstration plant for Erie Mining Company at Hoyt Lake, Minnesota. The fuel gas produced will be used to supplement natural gas and fuel oil for iron ore pellet induration. The fuel gas demonstration plant will consist of five stirred, two-stage fixed-bed gasifier retorts capable of handling caking and non-caking coals, and provisions for the installation of a sixth retort. The process and unit design has been based on operation with caking coals; however, the retorts have been designed for easy conversion to handle non-caking coals. The demonstration unit has been designed to provide for expansion to a commercial plant (described in Commercial Plant Package) in an economical manner.

  16. Sequences for Student Investigation

    Science.gov (United States)

    Barton, Jeffrey; Feil, David; Lartigue, David; Mullins, Bernadette

    2004-01-01

    We describe two classes of sequences that give rise to accessible problems for undergraduate research. These problems may be understood with virtually no prerequisites and are well suited for computer-aided investigation. The first sequence is a variation of one introduced by Stephen Wolfram in connection with his study of cellular automata. The…

  17. Sequence History Update Tool

    Science.gov (United States)

    Khanampompan, Teerapat; Gladden, Roy; Fisher, Forest; DelGuercio, Chris

    2008-01-01

    The Sequence History Update Tool performs Web-based sequence statistics archiving for Mars Reconnaissance Orbiter (MRO). Using a single UNIX command, the software takes advantage of sequencing conventions to automatically extract the needed statistics from multiple files. This information is then used to populate a PHP database, which is then seamlessly formatted into a dynamic Web page. This tool replaces a previous tedious and error-prone process of manually editing HTML code to construct a Web-based table. Because the tool manages all of the statistics gathering and file delivery to and from multiple data sources spread across multiple servers, there is also a considerable time and effort savings. With the use of The Sequence History Update Tool what previously took minutes is now done in less than 30 seconds, and now provides a more accurate archival record of the sequence commanding for MRO.

  18. Computer simulation of replacement sequences in copper

    International Nuclear Information System (INIS)

    Schiffgens, J.O.; Schwartz, D.W.; Ariyasu, R.G.; Cascadden, S.E.

    1978-01-01

    Results of computer simulations of , , and replacement sequences in copper are presented, including displacement thresholds, focusing energies, energy losses per replacement, and replacement sequence lengths. These parameters are tabulated for six interatomic potentials and shown to vary in a systematic way with potential stiffness and range. Comparisons of results from calculations made with ADDES, a quasi-dynamical code, and COMENT, a dynamical code, show excellent agreement, demonstrating that the former can be calibrated and used satisfactorily in the analysis of low energy displacement cascades. Upper limits on , , and replacement sequences were found to be approximately 10, approximately 30, and approximately 14 replacements, respectively. (author)

  19. Latitudinal patterns in phenotypic plasticity and fitness-related traits: assessing the climatic variability hypothesis (CVH with an invasive plant species.

    Directory of Open Access Journals (Sweden)

    Marco A Molina-Montenegro

    Full Text Available Phenotypic plasticity has been suggested as the main mechanism for species persistence under a global change scenario, and also as one of the main mechanisms that alien species use to tolerate and invade broad geographic areas. However, contrasting with this central role of phenotypic plasticity, standard models aimed to predict the effect of climatic change on species distributions do not allow for the inclusion of differences in plastic responses among populations. In this context, the climatic variability hypothesis (CVH, which states that higher thermal variability at higher latitudes should determine an increase in phenotypic plasticity with latitude, could be considered a timely and promising hypothesis. Accordingly, in this study we evaluated, for the first time in a plant species (Taraxacum officinale, the prediction of the CVH. Specifically, we measured plastic responses at different environmental temperatures (5 and 20°C, in several ecophysiological and fitness-related traits for five populations distributed along a broad latitudinal gradient. Overall, phenotypic plasticity increased with latitude for all six traits analyzed, and mean trait values increased with latitude at both experimental temperatures, the change was noticeably greater at 20° than at 5°C. Our results suggest that the positive relationship found between phenotypic plasticity and geographic latitude could have very deep implications on future species persistence and invasion processes under a scenario of climate change.

  20. Species composition, diversity and stratification in subtropical evergreen broadleaf forests along a latitudinal thermal gradient in the Ryukyu Archipelago, Japan

    Directory of Open Access Journals (Sweden)

    S.M. Feroz

    2015-07-01

    Full Text Available A well-developed evergreen broadleaf forest exists in the northern part of Okinawa and in the central part of the Ishigaki Islands in the Ryukyu Archipelago, Japan. All woody plants were identified to species level and their heights and diameters were measured in a 750m2 plot in Okinawa and a 400m2 plot in the Ishigaki Islands. Species overlap, dominance, diversity, multi-strata structure, and spatial distribution were calculated. The floristic composition in Okinawa was found to be different from that in Ishigaki. The species overlap between strata was higher in Okinawa than in Ishigaki. Species diversity and evenness tended to increase from the top down in Okinawa and the reverse in Ishigaki. Mean tree weight of each stratum decreased and tree density increased from top down in both forests. This trend resembled the mean weight–density trajectory of self-thinning plant populations. The degree of stand stratification, species richness and species diversity for trees with DBH ⩾4.5  cm increased along the latitudinal thermal gradient in the Ryukyu Archipelago. Thus, trees in the lower strata of Okinawa and upper strata of Ishigaki are important for sustainable maintenance of higher woody species diversity in the Ryukyu Archipelago.

  1. Latitudinal Distributions of Auroral Zone Electric Fields and Ground Magnetic Perturbations and Their Response to Variations in the Interplanetary Magnetic Field

    International Nuclear Information System (INIS)

    Horwitz, J.L.; Doupnik, J.R.; Banks, P.M.; Kamide, Y.; Akasofu, S.

    1978-01-01

    Chatanika observations of latitudinal distributions of convection electric fields (E 1 ) are compared with isointensity ΔH contours in latitude and time from the Alaskan magnetometer chain and with the north-south component of the interplanetary magnetic field (IMF B/sub z/m) from Imp-J. As expected, northward electric fields were generally observed within latitude and time regions where ΔH was positive, while southward electric fields were observed within negative ΔH regions. However, correlation between the magnitudes of the electric fields and of the ΔH perturbations was not strong, owing to variability in ionospheric conductivities produced by precipitation and solar illumination. In the midnight sector the northward-to-southward transition in the electric field and positive-to-negative ΔH transition were roughly collocated (to within 1 hour in local time) as signatures of the Harang discontinuity. The most important findings are that (1) southward (northward) IMF B/sub z/m transitions caused rapid equatorward (poleward) shifts of the electric field and ΔH patterns and (2) southward IMF B/sub z/ transitions, magnetospheric substorms, and local time transitions of the Harang discontinuity can all lead to northward-to-southward transitions of the electric field in the midnight sector. Due to the interlaced phasing of each of these three causal mechanisms a highly complex temporal pattern of electric fields results

  2. Carbon dioxide emissions from fossil fuel consumption and cement manufacture, 1751-1991, and an estimate of their isotopic composition and latitudinal distribution

    Energy Technology Data Exchange (ETDEWEB)

    Andres, R.J.; Marland, G.; Boden, T.; Bischof, S. [University of Alaska, Fairbanks, AK (USA). Inst. of Northern Engineering

    2000-05-01

    This work briefly discusses four of the current research emphases at Oak Ridge National Laboratory regarding the emission of CO{sub 2} from fossil fuel consumption, natural gas flaring, and cement manufacture. These emphases include: (1) updating the 1950 to present time series of CO{sub 2} emissions from fossil fuel consumption and cement manufacture, (2) extending this time series back to 1751, (3) gridding the data at 1 x 1{degree} resolution, and (4) estimating the isotopic signature of these emissions. A latitudinal distribution of carbon emissions is being completed. A southward shift in the major mass of CO{sub 2} emissions is occurring from European-North American latitudes toward Central-Southeast Asian latitudes, reflecting the growth of population and industrialization at these lower latitudes. The carbon isotopic signature of these CO{sub 2} emissions has been reexamined. The emissions of the past two decades were approximately 1% lighter than previously estimated. 37 refs., 5 figs., 5 tabs.

  3. Progenesis in Proctoeces lintoni (Fellodistomidae), a parasite of Fissurella crassa (Archaeogastropoda) in a latitudinal gradient in the Pacific Coast of South America.

    Science.gov (United States)

    Oliva, M E; Huaquin, L G

    2000-08-01

    The fellodistomid Proctoeces lintoni is a common parasite of the gonads of key-hole limpets Fissurella spp. (Archaeogastropoda). It has also been found in the mantle of Octopus vulgaris and as an intestinal parasite of haemulid and gobiesocid fishes. Fissurella crassa, a host for progenetic P. lintoni, can be found from Huarmey, Peni (10 degrees S) to Chiloé, Chile (42 degrees S). Proctoeces lintoni has been found parasitizing fishes and molluscs from Callao, Peni (12 degrees S) to Valdivia, Chile (39 degrees S). Progenesis is thought to be a latitude-dependent phenomenon, and high progenesis is expected at higher latitude. In the present article, the association between latitude and progenesis was examined over a latitudinal gradient of about 3,000 km. Data suggest that progenesis of P. lintoni infecting F. crassa was not associated with latitude. Low levels of progenesis found in the Peruvian population could be a consequence of parasite-induced mortality rather than of low latitude, as would be predicted by the latitude dependence hypothesis.

  4. Latitudinal patterns in phenotypic plasticity and fitness-related traits: assessing the climatic variability hypothesis (CVH) with an invasive plant species.

    Science.gov (United States)

    Molina-Montenegro, Marco A; Naya, Daniel E

    2012-01-01

    Phenotypic plasticity has been suggested as the main mechanism for species persistence under a global change scenario, and also as one of the main mechanisms that alien species use to tolerate and invade broad geographic areas. However, contrasting with this central role of phenotypic plasticity, standard models aimed to predict the effect of climatic change on species distributions do not allow for the inclusion of differences in plastic responses among populations. In this context, the climatic variability hypothesis (CVH), which states that higher thermal variability at higher latitudes should determine an increase in phenotypic plasticity with latitude, could be considered a timely and promising hypothesis. Accordingly, in this study we evaluated, for the first time in a plant species (Taraxacum officinale), the prediction of the CVH. Specifically, we measured plastic responses at different environmental temperatures (5 and 20°C), in several ecophysiological and fitness-related traits for five populations distributed along a broad latitudinal gradient. Overall, phenotypic plasticity increased with latitude for all six traits analyzed, and mean trait values increased with latitude at both experimental temperatures, the change was noticeably greater at 20° than at 5°C. Our results suggest that the positive relationship found between phenotypic plasticity and geographic latitude could have very deep implications on future species persistence and invasion processes under a scenario of climate change.

  5. Buried Waste Integrated Demonstration Plan

    International Nuclear Information System (INIS)

    Kostelnik, K.M.

    1991-12-01

    This document presents the plan of activities for the Buried Waste Integrated Demonstration (BWID) program which supports the environmental restoration (ER) objectives of the Department of Energy (DOE) Complex. Discussed in this plan are the objectives, organization, roles and responsibilities, and the process for implementing and managing BWID. BWID is hosted at the Idaho National Engineering Laboratory (INEL), but involves participants from throughout the DOE Complex, private industry, universities, and the international community. These participants will support, demonstrate, and evaluate a suite of advanced technologies representing a comprehensive remediation system for the effective and efficient remediation of buried waste. The processes for identifying technological needs, screening candidate technologies for applicability and maturity, selecting appropriate technologies for demonstration, field demonstrating, evaluation of results and transferring technologies to environmental restoration programs are also presented. This document further describes the elements of project planning and control that apply to BWID. It addresses the management processes, operating procedures, programmatic and technical objectives, and schedules. Key functions in support of each demonstration such as regulatory coordination, safety analyses, risk evaluations, facility requirements, and data management are presented

  6. Auditory demonstrations simulating Mayan architecture

    Science.gov (United States)

    Lubman, David

    2005-09-01

    Fascination with the ancient temples and ball court at Chichen Itza provide rich opportunities for science education. Children of all ages are delighted to learn that the sound of handclaps scattered from long temple staircases are transformed into bird chirps. Their engagement in such seemingly magical phenomena provides magic moments for teaching acoustical principals, including the picket-fence effect (PFE). PFE transforms impulsive sounds scattered from spatially periodic structures into tonal sounds. PFE is demonstrated with a computer possessing a sound card and a simple sound editing program. The inverse relationship between tonal frequency and the time interval between periodic impulses is easily demonstrated. The number of impulses needed to produce an audible tone is easily demonstrated and compared with the number of steps on the staircase. Transformation of audible tones into downward-gliding chirps is simulated by monotonically increasing the time between impulses. The Great Ball Court also provides opportunities for acoustical demonstration. Observers clapping their hands while standing between the long, tall, and parallel walls of the playing field marvel at the profound flutter echo heard for about 1.5 s. The flutter echo sonogram demonstrates the speed of sound and frequency-selective atmospheric attenuation.

  7. Demonstration of reliability centered maintenance

    International Nuclear Information System (INIS)

    Schwan, C.A.; Morgan, T.A.

    1991-04-01

    Reliability centered maintenance (RCM) is an approach to preventive maintenance planning and evaluation that has been used successfully by other industries, most notably the airlines and military. Now EPRI is demonstrating RCM in the commercial nuclear power industry. Just completed are large-scale, two-year demonstrations at Rochester Gas ampersand Electric (Ginna Nuclear Power Station) and Southern California Edison (San Onofre Nuclear Generating Station). Both demonstrations were begun in the spring of 1988. At each plant, RCM was performed on 12 to 21 major systems. Both demonstrations determined that RCM is an appropriate means to optimize a PM program and improve nuclear plant preventive maintenance on a large scale. Such favorable results had been suggested by three earlier EPRI pilot studies at Florida Power ampersand Light, Duke Power, and Southern California Edison. EPRI selected the Ginna and San Onofre sites because, together, they represent a broad range of utility and plant size, plant organization, plant age, and histories of availability and reliability. Significant steps in each demonstration included: selecting and prioritizing plant systems for RCM evaluation; performing the RCM evaluation steps on selected systems; evaluating the RCM recommendations by a multi-disciplinary task force; implementing the RCM recommendations; establishing a system to track and verify the RCM benefits; and establishing procedures to update the RCM bases and recommendations with time (a living program). 7 refs., 1 tab

  8. Latitudinal and longitudinal behavior of the geomagnetic field during a disturbed period: A case study using wavelet techniques

    Science.gov (United States)

    Klausner, Virginia; Domingues, Margarete Oliveira; Mendes, Odim; da Costa, Aracy Mendes; Papa, Andres Reinaldo Rodriguez; Gonzalez, Arian Ojeda

    2016-11-01

    -components. In the latitude range from ∼ 40 ° S to ∼ 60 ° N, the wavelet signatures do not show remarkable differences, except for the amplitudes of the wavelet coefficients. The sequence of transient field variations detected at auroral latitudes is probably associated to occurrences of substorms, while at lower latitudes, these variations are associated to the enhancement of the ring current.

  9. Demonstration of blind quantum computing.

    Science.gov (United States)

    Barz, Stefanie; Kashefi, Elham; Broadbent, Anne; Fitzsimons, Joseph F; Zeilinger, Anton; Walther, Philip

    2012-01-20

    Quantum computers, besides offering substantial computational speedups, are also expected to preserve the privacy of a computation. We present an experimental demonstration of blind quantum computing in which the input, computation, and output all remain unknown to the computer. We exploit the conceptual framework of measurement-based quantum computation that enables a client to delegate a computation to a quantum server. Various blind delegated computations, including one- and two-qubit gates and the Deutsch and Grover quantum algorithms, are demonstrated. The client only needs to be able to prepare and transmit individual photonic qubits. Our demonstration is crucial for unconditionally secure quantum cloud computing and might become a key ingredient for real-life applications, especially when considering the challenges of making powerful quantum computers widely available.

  10. Savannah River Plant incinerator demonstration

    International Nuclear Information System (INIS)

    Lewandowski, K.E.

    1983-01-01

    A full-scale incineration process was demonstrated at the Savannah River Laboratory (SRL) using nonradioactive waste. From October 1981 through September 1982, 15,700 kilograms of solid waste and 5.7 m 3 of solvent were incinerated. Emissions of off-gas components (NO/sub x/, SO 2 , CO, and particulates) were well below South Carolina state standards. Volume reductions of 20:1 for solid waste and 7:1 for Purex solvent/lime slurry were achieved. The process has been relocated and upgraded by the Savannah River Plant to accept low-level beta-gamma combustibles. During a two-year demonstration, the facility will incinerate slightly radioactive ( 3 ) solvent and suspect level (< 1 mR/h at 0.0254 meter) solid wastes. This demonstration will begin in early 1984

  11. Compressing DNA sequence databases with coil

    Directory of Open Access Journals (Sweden)

    Hendy Michael D

    2008-05-01

    Full Text Available Abstract Background Publicly available DNA sequence databases such as GenBank are large, and are growing at an exponential rate. The sheer volume of data being dealt with presents serious storage and data communications problems. Currently, sequence data is usually kept in large "flat files," which are then compressed using standard Lempel-Ziv (gzip compression – an approach which rarely achieves good compression ratios. While much research has been done on compressing individual DNA sequences, surprisingly little has focused on the compression of entire databases of such sequences. In this study we introduce the sequence database compression software coil. Results We have designed and implemented a portable software package, coil, for compressing and decompressing DNA sequence databases based on the idea of edit-tree coding. coil is geared towards achieving high compression ratios at the expense of execution time and memory usage during compression – the compression time represents a "one-off investment" whose cost is quickly amortised if the resulting compressed file is transmitted many times. Decompression requires little memory and is extremely fast. We demonstrate a 5% improvement in compression ratio over state-of-the-art general-purpose compression tools for a large GenBank database file containing Expressed Sequence Tag (EST data. Finally, coil can efficiently encode incremental additions to a sequence database. Conclusion coil presents a compelling alternative to conventional compression of flat files for the storage and distribution of DNA sequence databases having a narrow distribution of sequence lengths, such as EST data. Increasing compression levels for databases having a wide distribution of sequence lengths is a direction for future work.

  12. Protecting genomic sequence anonymity with generalization lattices.

    Science.gov (United States)

    Malin, B A

    2005-01-01

    Current genomic privacy technologies assume the identity of genomic sequence data is protected if personal information, such as demographics, are obscured, removed, or encrypted. While demographic features can directly compromise an individual's identity, recent research demonstrates such protections are insufficient because sequence data itself is susceptible to re-identification. To counteract this problem, we introduce an algorithm for anonymizing a collection of person-specific DNA sequences. The technique is termed DNA lattice anonymization (DNALA), and is based upon the formal privacy protection schema of k -anonymity. Under this model, it is impossible to observe or learn features that distinguish one genetic sequence from k-1 other entries in a collection. To maximize information retained in protected sequences, we incorporate a concept generalization lattice to learn the distance between two residues in a single nucleotide region. The lattice provides the most similar generalized concept for two residues (e.g. adenine and guanine are both purines). The method is tested and evaluated with several publicly available human population datasets ranging in size from 30 to 400 sequences. Our findings imply the anonymization schema is feasible for the protection of sequences privacy. The DNALA method is the first computational disclosure control technique for general DNA sequences. Given the computational nature of the method, guarantees of anonymity can be formally proven. There is room for improvement and validation, though this research provides the groundwork from which future researchers can construct genomics anonymization schemas tailored to specific datasharing scenarios.

  13. HIV Sequence Compendium 2015

    Energy Technology Data Exchange (ETDEWEB)

    Foley, Brian Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Leitner, Thomas Kenneth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Apetrei, Cristian [Univ. of Pittsburgh, PA (United States); Hahn, Beatrice [Univ. of Pennsylvania, Philadelphia, PA (United States); Mizrachi, Ilene [National Center for Biotechnology Information, Bethesda, MD (United States); Mullins, James [Univ. of Washington, Seattle, WA (United States); Rambaut, Andrew [Univ. of Edinburgh, Scotland (United Kingdom); Wolinsky, Steven [Northwestern Univ., Evanston, IL (United States); Korber, Bette Tina Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-10-05

    This compendium is an annual printed summary of the data contained in the HIV sequence database. We try to present a judicious selection of the data in such a way that it is of maximum utility to HIV researchers. Each of the alignments attempts to display the genetic variability within the different species, groups and subtypes of the virus. This compendium contains sequences published before January 1, 2015. Hence, though it is published in 2015 and called the 2015 Compendium, its contents correspond to the 2014 curated alignments on our website. The number of sequences in the HIV database is still increasing. In total, at the end of 2014, there were 624,121 sequences in the HIV Sequence Database, an increase of 7% since the previous year. This is the first year that the number of new sequences added to the database has decreased compared to the previous year. The number of near complete genomes (>7000 nucleotides) increased to 5834 by end of 2014. However, as in previous years, the compendium alignments contain only a fraction of these. A more complete version of all alignments is available on our website, http://www.hiv.lanl.gov/ content/sequence/NEWALIGN/align.html As always, we are open to complaints and suggestions for improvement. Inquiries and comments regarding the compendium should be addressed to seq-info@lanl.gov.

  14. Mapping sequences by parts

    Directory of Open Access Journals (Sweden)

    Guziolowski Carito

    2007-09-01

    Full Text Available Abstract Background: We present the N-map method, a pairwise and asymmetrical approach which allows us to compare sequences by taking into account evolutionary events that produce shuffled, reversed or repeated elements. Basically, the optimal N-map of a sequence s over a sequence t is the best way of partitioning the first sequence into N parts and placing them, possibly complementary reversed, over the second sequence in order to maximize the sum of their gapless alignment scores. Results: We introduce an algorithm computing an optimal N-map with time complexity O (|s| × |t| × N using O (|s| × |t| × N memory space. Among all the numbers of parts taken in a reasonable range, we select the value N for which the optimal N-map has the most significant score. To evaluate this significance, we study the empirical distributions of the scores of optimal N-maps and show that they can be approximated by normal distributions with a reasonable accuracy. We test the functionality of the approach over random sequences on which we apply artificial evolutionary events. Practical Application: The method is illustrated with four case studies of pairs of sequences involving non-standard evolutionary events.

  15. Demonstrating Interactions of Transcription Factors with DNA by Electrophoretic Mobility Shift Assay.

    Science.gov (United States)

    Yousaf, Nasim; Gould, David

    2017-01-01

    Confirming the binding of a transcription factor with a particular DNA sequence may be important in characterizing interactions with a synthetic promoter. Electrophoretic mobility shift assay is a powerful approach to demonstrate the specific DNA sequence that is bound by a transcription factor and also to confirm the specific transcription factor involved in the interaction. In this chapter we describe a method we have successfully used to demonstrate interactions of endogenous transcription factors with sequences derived from endogenous and synthetic promoters.

  16. The Colliding Beams Sequencer

    International Nuclear Information System (INIS)

    Johnson, D.E.; Johnson, R.P.

    1989-01-01

    The Colliding Beam Sequencer (CBS) is a computer program used to operate the pbar-p Collider by synchronizing the applications programs and simulating the activities of the accelerator operators during filling and storage. The Sequencer acts as a meta-program, running otherwise stand alone applications programs, to do the set-up, beam transfers, acceleration, low beta turn on, and diagnostics for the transfers and storage. The Sequencer and its operational performance will be described along with its special features which include a periodic scheduler and command logger. 14 refs., 3 figs

  17. Phylogenetic Trees From Sequences

    Science.gov (United States)

    Ryvkin, Paul; Wang, Li-San

    In this chapter, we review important concepts and approaches for phylogeny reconstruction from sequence data.We first cover some basic definitions and properties of phylogenetics, and briefly explain how scientists model sequence evolution and measure sequence divergence. We then discuss three major approaches for phylogenetic reconstruction: distance-based phylogenetic reconstruction, maximum parsimony, and maximum likelihood. In the third part of the chapter, we review how multiple phylogenies are compared by consensus methods and how to assess confidence using bootstrapping. At the end of the chapter are two sections that list popular software packages and additional reading.

  18. Demonstrating Fermat's Principle in Optics

    Science.gov (United States)

    Paleiov, Orr; Pupko, Ofir; Lipson, S. G.

    2011-01-01

    We demonstrate Fermat's principle in optics by a simple experiment using reflection from an arbitrarily shaped one-dimensional reflector. We investigated a range of possible light paths from a lamp to a fixed slit by reflection in a curved reflector and showed by direct measurement that the paths along which light is concentrated have either…

  19. Some Field Demonstrations in India

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Some Field Demonstrations in India. 2x150kVAR STATCOM at M/s Hindusthan Latex, Trivandrum. 250kVAR, 800V dc, 2-level STATCOM (Installed at Peekey Steels, Calicut). 250kVAR,800V dc, UPQC at CDAC, Trivandrum. REFERENCE: Website www. cdac.gov.in.

  20. Flexible-Rotor Balancing Demonstration

    Science.gov (United States)

    Giordano, J.; Zorzi, E.

    1986-01-01

    Report describes method for balancing high-speed rotors at relatively low speeds and discusses demonstration of method on laboratory test rig. Method ensures rotor brought up to speeds well over 20,000 r/min smoothly, without excessive vibration amplitude at critical speeds or at operating speed.

  1. A Demonstration and a Souvenir

    Science.gov (United States)

    Lentz, Randy

    1978-01-01

    Describes an activity using interchangeable, preset tool holders to provide a demonstration for parents or students attending a school's open house session that produces a small souvenir (an aluminum mini-chalice) for them. A procedure sheet for the school's individual lathe and specification diagrams for making the cup are provided. (TA)

  2. NDT performance demonstration in Spain

    International Nuclear Information System (INIS)

    Bollini, G.J.

    1994-01-01

    The experience obtained from the in-service inspection of reactor pressure vessels (RPV) of Spanish nuclear power plants and the participation in several international programs, such as PISC, has shown the need for a performance demonstration, not only for the ultrasonic inspection techniques of RPV, but also for other ISI non-destructive techniques as in the case of eddy current inspection of steam generator tubing. Section XI of the ASME Code, which is applied in Spain for ISI, has incorporated recently the Appendix VIII for performance demonstration of ultrasonic inspection techniques. As a direct consequence of this, a Spanish project for performance demonstration of ultrasonic inspection techniques has been launched recently, which includes the manufacturing of full-scale mock-ups of nozzle to vessel welds, reactor vessel welds, wrought austenitic piping welds and ferritic piping welds of PWR and BWR nuclear power plants from different suppliers. This considerable technical effort will let the different Spanish organizations which are part of the project to participate and colaborate with similar international projects and in particular with a European initiative for performance demonstration. (Author)

  3. SunJammer Technology Demonstration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Sunjammer Project is a NASA funded contract to L?Garde Inc. to fly a solar sail demonstration for a period of approximately one year. L?Garde is also partnered...

  4. The buried waste integrated demonstration

    International Nuclear Information System (INIS)

    Kostelnik, K.M.

    1991-01-01

    There are numerous locations throughout the Department of Energy (DOE) Complex where wastes have been buried in the ground or stored for future disposal. Much of this buried waste is contaminated with hazardous and radioactive materials. An extensive research program has been initiated at the Idaho National Engineering Laboratory (INEL) to develop and demonstrate advanced remediation techniques for DOE Complex buried waste. The purpose of the Buried Waste Integrated Demonstration (BWID), is to develop a scientifically sound and deployable remediation system consisting of advanced technologies which address the buried waste characteristics of the DOE Complex. This comprehensive remediation system win include technologies for the entire remediation cycle (cradle-to-grave). Technologies developed and demonstrated within the BWID will be transferred to the DOE Complex sites with buried waste, to private industry, and to universities. Multidirectional technology transfer is encouraged by the BWID. Identification and evaluation of plausible technological solutions are an ongoing activity of the BWID. A number of technologies are currently under development throughout the DOE Complex, private industry, and universities. Technology integration mechanisms have been established by BWID to facilitate collaborative research and demonstration of applicable remedial technologies for buried waste. Successful completion of the BWID will result in the development of a proven and deployable system at the INEL and other DOE Complex buried waste sites, thereby supporting the DOE Complex's environmental restoration objectives

  5. E/Z MAS demonstration

    International Nuclear Information System (INIS)

    Boor, M.G.; Hurford, J.M.; Landry, R.P.; Martinez, B.J.; Solem, A.M.; Whiteson, R.; Zardecki, A.

    1998-01-01

    Los Alamos National Laboratory has developed E/Z MAS, a new generation nuclear material accountability application based on the latest technology and designed for facilities required to track nuclear materials with a simple-to-use interface. E/Z MAS is based on years of experience spent developing nuclear material accounting systems. E/Z MAS uses a modern relational database with a web server and enables users on a classified local area network to interact with the database with web browsers. The E/Z MAS Demonstration poster session demonstrates the E/Z MAS functions required by an operational nuclear facility to track material as it enters and leaves a facility and to account for the material as it moves through a process. The generation of internal facility reports and external reports for the Russian Federal system will be demonstrated. Bar-code readers will be used to demonstrate the ability of EZ MAS to automate certain functions, such as physical inventories at facilities

  6. US GCFR demonstration plant design

    International Nuclear Information System (INIS)

    Hunt, P.S.; Snyder, H.J.

    1980-05-01

    A general description of the US GCFR demonstration plant conceptual design is given to provide a context for more detailed papers to follow. The parameters selected for use in the design are presented and the basis for parameter selection is discussed. Nuclear steam supply system (NSSS) and balance of plant (BOP) component arrangements and systems are briefly discussed

  7. Satellite Demonstration: The Videodisc Technology.

    Science.gov (United States)

    Propp, George; And Others

    1979-01-01

    Originally part of a symposium on educational media for the deaf, the paper describes a satellite demonstration of video disc materials. It is explained that a panel of deaf individuals in Washington, D.C. and another in Nebraska came into direct two-way communication for the first time, and video disc materials were broadcast via the satellite.…

  8. Probabilistic Motor Sequence Yields Greater Offline and Less Online Learning than Fixed Sequence.

    Science.gov (United States)

    Du, Yue; Prashad, Shikha; Schoenbrun, Ilana; Clark, Jane E

    2016-01-01

    It is well acknowledged that motor sequences can be learned quickly through online learning. Subsequently, the initial acquisition of a motor sequence is boosted or consolidated by offline learning. However, little is known whether offline learning can drive the fast learning of motor sequences (i.e., initial sequence learning in the first training session). To examine offline learning in the fast learning stage, we asked four groups of young adults to perform the serial reaction time (SRT) task with either a fixed or probabilistic sequence and with or without preliminary knowledge (PK) of the presence of a sequence. The sequence and PK were manipulated to emphasize either procedural (probabilistic sequence; no preliminary knowledge (NPK)) or declarative (fixed sequence; with PK) memory that were found to either facilitate or inhibit offline learning. In the SRT task, there were six learning blocks with a 2 min break between each consecutive block. Throughout the session, stimuli followed the same fixed or probabilistic pattern except in Block 5, in which stimuli appeared in a random order. We found that PK facilitated the learning of a fixed sequence, but not a probabilistic sequence. In addition to overall learning measured by the mean reaction time (RT), we examined the progressive changes in RT within and between blocks (i.e., online and offline learning, respectively). It was found that the two groups who performed the fixed sequence, regardless of PK, showed greater online learning than the other two groups who performed the probabilistic sequence. The groups who performed the probabilistic sequence, regardless of PK, did not display online learning, as indicated by a decline in performance within the learning blocks. However, they did demonstrate remarkably greater offline improvement in RT, which suggests that they are learning the probabilistic sequence offline. These results suggest that in the SRT task, the fast acquisition of a motor sequence is driven

  9. DOE's annealing prototype demonstration projects

    International Nuclear Information System (INIS)

    Warren, J.; Nakos, J.; Rochau, G.

    1997-01-01

    One of the challenges U.S. utilities face in addressing technical issues associated with the aging of nuclear power plants is the long-term effect of plant operation on reactor pressure vessels (RPVs). As a nuclear plant operates, its RPV is exposed to neutrons. For certain plants, this neutron exposure can cause embrittlement of some of the RPV welds which can shorten the useful life of the RPV. This RPV embrittlement issue has the potential to affect the continued operation of a number of operating U.S. pressurized water reactor (PWR) plants. However, RPV material properties affected by long-term irradiation are recoverable through a thermal annealing treatment of the RPV. Although a dozen Russian-designed RPVs and several U.S. military vessels have been successfully annealed, U.S. utilities have stated that a successful annealing demonstration of a U.S. RPV is a prerequisite for annealing a licensed U.S. nuclear power plant. In May 1995, the Department of Energy's Sandia National Laboratories awarded two cost-shared contracts to evaluate the feasibility of annealing U.S. licensed plants by conducting an anneal of an installed RPV using two different heating technologies. The contracts were awarded to the American Society of Mechanical Engineers (ASME) Center for Research and Technology Development (CRTD) and MPR Associates (MPR). The ASME team completed its annealing prototype demonstration in July 1996, using an indirect gas furnace at the uncompleted Public Service of Indiana's Marble Hill nuclear power plant. The MPR team's annealing prototype demonstration was scheduled to be completed in early 1997, using a direct heat electrical furnace at the uncompleted Consumers Power Company's nuclear power plant at Midland, Michigan. This paper describes the Department's annealing prototype demonstration goals and objectives; the tasks, deliverables, and results to date for each annealing prototype demonstration; and the remaining annealing technology challenges

  10. Sequence complexity and work extraction

    International Nuclear Information System (INIS)

    Merhav, Neri

    2015-01-01

    We consider a simplified version of a solvable model by Mandal and Jarzynski, which constructively demonstrates the interplay between work extraction and the increase of the Shannon entropy of an information reservoir which is in contact with a physical system. We extend Mandal and Jarzynski’s main findings in several directions: first, we allow sequences of correlated bits rather than just independent bits. Secondly, at least for the case of binary information, we show that, in fact, the Shannon entropy is only one measure of complexity of the information that must increase in order for work to be extracted. The extracted work can also be upper bounded in terms of the increase in other quantities that measure complexity, like the predictability of future bits from past ones. Third, we provide an extension to the case of non-binary information (i.e. a larger alphabet), and finally, we extend the scope to the case where the incoming bits (before the interaction) form an individual sequence, rather than a random one. In this case, the entropy before the interaction can be replaced by the Lempel–Ziv (LZ) complexity of the incoming sequence, a fact that gives rise to an entropic meaning of the LZ complexity, not only in information theory, but also in physics. (paper)

  11. Gomphid DNA sequence data

    Data.gov (United States)

    U.S. Environmental Protection Agency — DNA sequence data for several genetic loci. This dataset is not publicly accessible because: It's already publicly available on GenBank. It can be accessed through...

  12. Yeast genome sequencing:

    DEFF Research Database (Denmark)

    Piskur, Jure; Langkjær, Rikke Breinhold

    2004-01-01

    For decades, unicellular yeasts have been general models to help understand the eukaryotic cell and also our own biology. Recently, over a dozen yeast genomes have been sequenced, providing the basis to resolve several complex biological questions. Analysis of the novel sequence data has shown...... of closely related species helps in gene annotation and to answer how many genes there really are within the genomes. Analysis of non-coding regions among closely related species has provided an example of how to determine novel gene regulatory sequences, which were previously difficult to analyse because...... they are short and degenerate and occupy different positions. Comparative genomics helps to understand the origin of yeasts and points out crucial molecular events in yeast evolutionary history, such as whole-genome duplication and horizontal gene transfer(s). In addition, the accumulating sequence data provide...

  13. Irvine Smart Grid Demonstration, a Regional Smart Grid Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Yinger, Robert [Southern California Edison Company, Rosemead, CA (United States); Irwin, Mark [Southern California Edison Company, Rosemead, CA (United States)

    2015-12-29

    ISGD was a comprehensive demonstration that spanned the electricity delivery system and extended into customer homes. The project used phasor measurement technology to enable substation-level situational awareness, and demonstrated SCE’s next-generation substation automation system. It extended beyond the substation to evaluate the latest generation of distribution automation technologies, including looped 12-kV distribution circuit topology using URCIs. The project team used DVVC capabilities to demonstrate CVR. In customer homes, the project evaluated HAN devices such as smart appliances, programmable communicating thermostats, and home energy management components. The homes were also equipped with energy storage, solar PV systems, and a number of energy efficiency measures (EEMs). The team used one block of homes to evaluate strategies and technologies for achieving ZNE. A home achieves ZNE when it produces at least as much renewable energy as the amount of energy it consumes annually. The project also assessed the impact of device-specific demand response (DR), as well as load management capabilities involving energy storage devices and plug-in electric vehicle charging equipment. In addition, the ISGD project sought to better understand the impact of ZNE homes on the electric grid. ISGD’s SENet enabled end-to-end interoperability between multiple vendors’ systems and devices, while also providing a level of cybersecurity that is essential to smart grid development and adoption across the nation. The ISGD project includes a series of sub-projects grouped into four logical technology domains: Smart Energy Customer Solutions, Next-Generation Distribution System, Interoperability and Cybersecurity, and Workforce of the Future. Section 2.3 provides a more detailed overview of these domains.

  14. Dynamic Sequence Assignment.

    Science.gov (United States)

    1983-12-01

    D-136 548 DYNAMIIC SEQUENCE ASSIGNMENT(U) ADVANCED INFORMATION AND 1/2 DECISION SYSTEMS MOUNTAIN YIELW CA C A 0 REILLY ET AL. UNCLSSIIED DEC 83 AI/DS...I ADVANCED INFORMATION & DECISION SYSTEMS Mountain View. CA 94040 84 u ,53 V,..’. Unclassified _____ SCURITY CLASSIFICATION OF THIS PAGE REPORT...reviews some important heuristic algorithms developed for fas- ter solution of the sequence assignment problem. 3.1. DINAMIC MOGRAMUNIG FORMULATION FOR

  15. HIV Sequence Compendium 2010

    Energy Technology Data Exchange (ETDEWEB)

    Kuiken, Carla [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Foley, Brian [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Leitner, Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Apetrei, Christian [Univ. of Pittsburgh, PA (United States); Hahn, Beatrice [Univ. of Alabama, Tuscaloosa, AL (United States); Mizrachi, Ilene [National Center for Biotechnology Information, Bethesda, MD (United States); Mullins, James [Univ. of Washington, Seattle, WA (United States); Rambaut, Andrew [Univ. of Edinburgh, Scotland (United Kingdom); Wolinsky, Steven [Northwestern Univ., Evanston, IL (United States); Korber, Bette [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2010-12-31

    This compendium is an annual printed summary of the data contained in the HIV sequence database. In these compendia we try to present a judicious selection of the data in such a way that it is of maximum utility to HIV researchers. Each of the alignments attempts to display the genetic variability within the different species, groups and subtypes of the virus. This compendium contains sequences published before January 1, 2010. Hence, though it is called the 2010 Compendium, its contents correspond to the 2009 curated alignments on our website. The number of sequences in the HIV database is still increasing exponentially. In total, at the time of printing, there were 339,306 sequences in the HIV Sequence Database, an increase of 45% since last year. The number of near complete genomes (>7000 nucleotides) increased to 2576 by end of 2009, reflecting a smaller increase than in previous years. However, as in previous years, the compendium alignments contain only a small fraction of these. Included in the alignments are a small number of sequences representing each of the subtypes and the more prevalent circulating recombinant forms (CRFs) such as 01 and 02, as well as a few outgroup sequences (group O and N and SIV-CPZ). Of the rarer CRFs we included one representative each. A more complete version of all alignments is available on our website, http://www.hiv.lanl.gov/content/sequence/NEWALIGN/align.html. Reprints are available from our website in the form of both HTML and PDF files. As always, we are open to complaints and suggestions for improvement. Inquiries and comments regarding the compendium should be addressed to seq-info@lanl.gov.

  16. General LTE Sequence

    OpenAIRE

    Billal, Masum

    2015-01-01

    In this paper,we have characterized sequences which maintain the same property described in Lifting the Exponent Lemma. Lifting the Exponent Lemma is a very powerful tool in olympiad number theory and recently it has become very popular. We generalize it to all sequences that maintain a property like it i.e. if p^{\\alpha}||a_k and p^\\b{eta}||n, then p^{{\\alpha}+\\b{eta}}||a_{nk}.

  17. Pairwise Sequence Alignment Library

    Energy Technology Data Exchange (ETDEWEB)

    2015-05-20

    Vector extensions, such as SSE, have been part of the x86 CPU since the 1990s, with applications in graphics, signal processing, and scientific applications. Although many algorithms and applications can naturally benefit from automatic vectorization techniques, there are still many that are difficult to vectorize due to their dependence on irregular data structures, dense branch operations, or data dependencies. Sequence alignment, one of the most widely used operations in bioinformatics workflows, has a computational footprint that features complex data dependencies. The trend of widening vector registers adversely affects the state-of-the-art sequence alignment algorithm based on striped data layouts. Therefore, a novel SIMD implementation of a parallel scan-based sequence alignment algorithm that can better exploit wider SIMD units was implemented as part of the Parallel Sequence Alignment Library (parasail). Parasail features: Reference implementations of all known vectorized sequence alignment approaches. Implementations of Smith Waterman (SW), semi-global (SG), and Needleman Wunsch (NW) sequence alignment algorithms. Implementations across all modern CPU instruction sets including AVX2 and KNC. Language interfaces for C/C++ and Python.

  18. Incineration demonstration at Savannah River

    International Nuclear Information System (INIS)

    Lewandowski, K.E.; Becker, G.W.; Mersman, K.E.; Roberson, W.A.

    1983-01-01

    A full-scale incineration process for Savannah River Plant (SRP) low level beta-gamma combustible waste was demonstrated at the Savannah River Laboratory (SRL) using nonradioactive wastes. From October 1981 through September 1982, 15,700 kilograms of solid waste and 5.7 m 3 of solvent were incinerated. Emissions of off-gas components (NO/sub x/, SO 2 , CO, and particulates) were well below South Carolina state standards. Volume reductions of 20:1 for solid waste and 7:1 for Purex solvent/lime slurry were achieved. Presently, the process is being upgraded by SRP to accept radioactive wastes. During a two-year SRP demonstration, the facility will be used to incinerate slightly radioactive ( 3 ) solvent and suspect level (<1 mR/hr at 0.0254 meter) solid wastes

  19. Plasma hearth process demonstration project

    International Nuclear Information System (INIS)

    Geimer, R.M.; Gillins, R.L.

    1995-01-01

    The Plasma Hearth Process (PHP) demonstration project is one of the key technology projects in the US Department of Energy (DOE) Office of Technology Development Mixed Waste Focus Area. The PHP is a high temperature thermal treatment process using a plasma arc torch in a stationary, refractory lined chamber that destroys organics and stabilizes the residuals in a nonleaching, vitrified waste form, greatly improving the disposability of the waste. This paper describes the PHP system and summarizes test results to date, including volume reduction, destruction and removal efficiencies for organic wastes, and emission characteristics. Tests performed so far demonstrate that the PHP adresses DOE mixed waste final waste form requirements and US Environmental Protection Agency Toxicity Characteristic Leaching Procedure requirements

  20. Actinide Separation Demonstration Facility, Tarapur

    International Nuclear Information System (INIS)

    Vishwaraj, I.

    2017-01-01

    Partitioning of minor actinide from high level waste could have a substantial impact in lowering the radio toxicity associated with high level waste as well as it will reduce the burden on geological repository. In Indian context, the partitioned minor actinide could be routed into the fast breeder reactor systems scheduled for commissioning in the near period. The technological breakthrough in solvent development has catalyzed the partitioning programme in India, leading to the setting up and hot commissioning of the Actinide Separation Demonstration Facility (ASDF) at BARC, Tarapur. The engineering scale Actinide Separation Demonstration Facility (ASDF) has been retrofitted in an available radiological hot cell situated adjacent to the Advanced Vitrification Facility (AVS). This location advantage ensures an uninterrupted supply of high-level waste and facilitates the vitrification of the high-level waste after separation of minor actinides

  1. Earth Science Capability Demonstration Project

    Science.gov (United States)

    Cobleigh, Brent

    2006-01-01

    A viewgraph presentation reviewing the Earth Science Capability Demonstration Project is shown. The contents include: 1) ESCD Project; 2) Available Flight Assets; 3) Ikhana Procurement; 4) GCS Layout; 5) Baseline Predator B Architecture; 6) Ikhana Architecture; 7) UAV Capability Assessment; 8) The Big Picture; 9) NASA/NOAA UAV Demo (5/05 to 9/05); 10) NASA/USFS Western States Fire Mission (8/06); and 11) Suborbital Telepresence.

  2. Mixed Waste Landfill Integrated Demonstration

    International Nuclear Information System (INIS)

    1994-02-01

    The mission of the Mixed Waste Landfill Integrated Demonstration (MWLID) is to demonstrate, in contaminated sites, new technologies for clean-up of chemical and mixed waste landfills that are representative of many sites throughout the DOE Complex and the nation. When implemented, these new technologies promise to characterize and remediate the contaminated landfill sites across the country that resulted from past waste disposal practices. Characterization and remediation technologies are aimed at making clean-up less expensive, safer, and more effective than current techniques. This will be done by emphasizing in-situ technologies. Most important, MWLID's success will be shared with other Federal, state, and local governments, and private companies that face the important task of waste site remediation. MWLID will demonstrate technologies at two existing landfills. Sandia National Laboratories' Chemical Waste Landfill received hazardous (chemical) waste from the Laboratory from 1962 to 1985, and the Mixed-Waste Landfill received hazardous and radioactive wastes (mixed wastes) over a twenty-nine year period (1959-1988) from various Sandia nuclear research programs. Both landfills are now closed. Originally, however, the sites were selected because of Albuquerque's and climate and the thick layer of alluvial deposits that overlay groundwater approximately 480 feet below the landfills. This thick layer of ''dry'' soils, gravel, and clays promised to be a natural barrier between the landfills and groundwater

  3. Salt decontamination demonstration test results

    International Nuclear Information System (INIS)

    Snell, E.B.; Heng, C.J.

    1983-06-01

    The Salt Decontamination Demonstration confirmed that the precipitation process could be used for large-scale decontamination of radioactive waste sale solution. Although a number of refinements are necessary to safely process the long-term requirement of 5 million gallons of waste salt solution per year, there were no observations to suggest that any fundamentals of the process require re-evaluation. Major accomplishments were: (1) 518,000 gallons of decontaminated filtrate were produced from 427,000 gallons of waste salt solution from tank 24H. The demonstration goal was to produce a minimum of 200,000 gallons of decontaminated salt solution; (2) cesium activity in the filtrate was reduced by a factor of 43,000 below the cesium activity in the tank 24 solution. This decontamination factor (DF) exceeded the demonstration goal of a DF greater than 10,000; (3) average strontium-90 activity in the filtrate was reduced by a factor of 26 to less than 10 3 d/m/ml versus a goal of less than 10 4 d/m/ml; and (4) the concentrated precipitate was washed to a final sodium ion concentration of 0.15 M, well below the 0.225 M upper limit for DWPF feed. These accomplishments were achieved on schedule and without incident. Total radiation exposure to personnel was less than 350 mrem and resulted primarily from sampling precipitate slurry inside tank 48. 3 references, 6 figures, 2 tables

  4. Aerospace Communications Security Technologies Demonstrated

    Science.gov (United States)

    Griner, James H.; Martzaklis, Konstantinos S.

    2003-01-01

    In light of the events of September 11, 2001, NASA senior management requested an investigation of technologies and concepts to enhance aviation security. The investigation was to focus on near-term technologies that could be demonstrated within 90 days and implemented in less than 2 years. In response to this request, an internal NASA Glenn Research Center Communications, Navigation, and Surveillance Aviation Security Tiger Team was assembled. The 2-year plan developed by the team included an investigation of multiple aviation security concepts, multiple aircraft platforms, and extensively leveraged datalink communications technologies. It incorporated industry partners from NASA's Graphical Weather-in-the-Cockpit research, which is within NASA's Aviation Safety Program. Two concepts from the plan were selected for demonstration: remote "black box," and cockpit/cabin surveillance. The remote "black box" concept involves real-time downlinking of aircraft parameters for remote monitoring and archiving of aircraft data, which would assure access to the data following the loss or inaccessibility of an aircraft. The cockpit/cabin surveillance concept involves remote audio and/or visual surveillance of cockpit and cabin activity, which would allow immediate response to any security breach and would serve as a possible deterrent to such breaches. The datalink selected for the demonstrations was VDL Mode 2 (VHF digital link), the first digital datalink for air-ground communications designed for aircraft use. VDL Mode 2 is beginning to be implemented through the deployment of ground stations and aircraft avionics installations, with the goal of being operational in 2 years. The first demonstration was performed December 3, 2001, onboard the LearJet 25 at Glenn. NASA worked with Honeywell, Inc., for the broadcast VDL Mode 2 datalink capability and with actual Boeing 757 aircraft data. This demonstration used a cockpitmounted camera for video surveillance and a coupling to

  5. Integration Process for the Habitat Demonstration Unit

    Science.gov (United States)

    Gill, Tracy; Merbitz, Jerad; Kennedy, Kriss; Tri, Terry; Howe, A. Scott

    2010-01-01

    The Habitat Demonstration Unit (HDU) is an experimental exploration habitat technology and architecture test platform designed for analog demonstration activities The HDU project has required a team to integrate a variety of contributions from NASA centers and outside collaborators and poses a challenge in integrating these disparate efforts into a cohesive architecture To complete the development of the HDU from conception in June 2009 to rollout for operations in July 2010, a cohesive integration strategy has been developed to integrate the various systems of HDU and the payloads, such as the Geology Lab, that those systems will support The utilization of interface design standards and uniquely tailored reviews have allowed for an accelerated design process Scheduled activities include early fit-checks and the utilization of a Habitat avionics test bed prior to equipment installation into HDU A coordinated effort to utilize modeling and simulation systems has aided in design and integration concept development Modeling tools have been effective in hardware systems layout, cable routing and length estimation, and human factors analysis Decision processes on the shell development including the assembly sequence and the transportation have been fleshed out early on HDU to maximize the efficiency of both integration and field operations Incremental test operations leading up to an integrated systems test allows for an orderly systems test program The HDU will begin its journey as an emulation of a Pressurized Excursion Module (PEM) for 2010 field testing and then may evolve to a Pressurized Core Module (PCM) for 2011 and later field tests, depending on agency architecture decisions The HDU deployment will vary slightly from current lunar architecture plans to include developmental hardware and software items and additional systems called opportunities for technology demonstration One of the HDU challenges has been designing to be prepared for the integration of

  6. Nitrous oxide and methane in the Atlantic Ocean between 50°N and 52°S: Latitudinal distribution and sea-to-air flux

    Science.gov (United States)

    Forster, Grant; Upstill-Goddard, Rob C.; Gist, Niki; Robinson, Carol; Uher, Gunther; Woodward, E. Malcolm S.

    2009-07-01

    We discuss nitrous oxide (N 2O) and methane (CH 4) distributions in 49 vertical profiles covering the upper ˜300 m of the water column along two ˜13,500 km transects between ˜50°N and ˜52°S during the Atlantic Meridional Transect (AMT) programme (AMT cruises 12 and 13). Vertical N 2O profiles were amenable to analysis on the basis of common features coincident with Longhurst provinces. In contrast, CH 4 showed no such pattern. The most striking feature of the latitudinal depth distributions was a well-defined "plume" of exceptionally high N 2O concentrations coincident with very low levels of CH 4, located between ˜23.5°N and ˜23.5°S; this feature reflects the upwelling of deep waters containing N 2O derived from nitrification, as identified by an analysis of N 2O, apparent oxygen utilization (AOU) and NO 3-, and presumably depleted in CH 4 by bacterial oxidation. Sea-to-air emissions fluxes for a region equivalent to ˜42% of the Atlantic Ocean surface area were in the range 0.40-0.68 Tg N 2O yr -1 and 0.81-1.43 Tg CH 4 yr -1. Based on contemporary estimates of the global ocean source strengths of atmospheric N 2O and CH 4, the Atlantic Ocean could account for ˜6-15% and 4-13%, respectively, of these source totals. Given that the Atlantic Ocean accounts for around 20% of the global ocean surface, on unit area basis it appears that the Atlantic may be a slightly weaker source of atmospheric N 2O than other ocean regions but it could make a somewhat larger contribution to marine-derived atmospheric CH 4 than previously thought.

  7. High density of tree-cavities and snags in tropical dry forest of western Mexico raises questions for a latitudinal gradient.

    Directory of Open Access Journals (Sweden)

    Leopoldo Vázquez

    Full Text Available It has been suggested that a latitudinal gradient exists of a low density of snags and high density of naturally-formed tree-cavities in tropical vs. temperate forests, though few cavities may have characteristics suitable for nesting by birds. We determined snag and cavity density, characteristics, and suitability for birds in a tropical dry forest biome of western Mexico, and evaluated whether our data fits the trend of snag and cavity density typically found in tropical moist and wet forests. We established five 0.25-ha transects to survey and measure tree-cavities and snags in each of three vegetation types of deciduous, semi-deciduous, and mono-dominant Piranhea mexicana forest, comprising a total of 3.75 ha. We found a high density of 77 cavities/ha, with 37 cavities suitable for birds/ha, where density, and characteristics of cavities varied significantly among vegetation types. Lowest abundance of cavities occurred in deciduous forest, and these were in smaller trees, at a lower height, and with a narrower entrance diameter. Only 8.6% of cavities were excavated by woodpeckers, and only 11% of cavities were occupied, mainly by arthropods, though 52% of all cavities were unsuitable for birds. We also found a high density of 56 snags/ha, with greatest density in deciduous forest (70 snags/ha, though these were of significantly smaller diameter, and snags of larger diameter were more likely to contain cavities. The Chamela-Cuixmala tropical dry forest had the highest density of snags recorded for any tropical or temperate forest, and while snag density was significantly correlated with mean snag dbh, neither latitude nor mean dbh predicted snag density in ten forest sites. The high spatial aggregation of snag and cavity resources in tropical dry forest may limit their availability, particularly for large-bodied cavity adopters, and highlights the importance of habitat heterogeneity in providing resources for primary and secondary cavity-nesters.

  8. Ecological Diversity in South American Mammals: Their Geographical Distribution Shows Variable Associations with Phylogenetic Diversity and Does Not Follow the Latitudinal Richness Gradient.

    Directory of Open Access Journals (Sweden)

    Paula Nilda Fergnani

    Full Text Available The extent to which the latitudinal gradient in species richness may be paralleled by a similar gradient of increasing functional or phylogenetic diversity is a matter of controversy. We evaluated whether taxonomic richness (TR is informative in terms of ecological diversity (ED, an approximation to functional diversity and phylogenetic diversity (AvPD using data on 531 mammal species representing South American old autochthonous (marsupials, xenarthrans, mid-Cenozoic immigrants (hystricognaths, primates and newcomers (carnivorans, artiodactyls. If closely related species are ecologically more similar than distantly related species, AvPD will be a strong predictor of ED; however, lower ED than predicted from AvPD may be due to species retaining most of their ancestral characters, suggesting niche conservatism. This pattern could occur in tropical rainforests for taxa of tropical affinity (old autochthonous and mid-Cenozoic immigrants and in open and arid habitats for newcomers. In contrast, higher ED than expected from AvPD could occur, possibly in association with niche evolution, in arid and open habitats for taxa of tropical affinity and in forested habitats for newcomers. We found that TR was a poor predictor of ED and AvPD. After controlling for TR, there was considerable variability in the extent to which AvPD accounted for ED. Taxa of tropical affinity did not support the prediction of ED deficit within tropical rainforests, rather, they showed a mosaic of regions with an excess of ED interspersed with zones of ED deficit within the tropics; newcomers showed ED deficit in arid and open regions. Some taxa of tropical affinity showed excess of ED in tropical desert areas (hystricognaths or temperate semideserts (xenarthrans; newcomers showed excess of ED at cold-temperate latitudes in the Northern Hemisphere. This result suggests that extreme climatic conditions at both temperate and tropical latitudes may have promoted niche evolution in

  9. Carbon dioxide emissions from fossil fuel consumption and cement manufacture, 1751-1991; and an estimate of their isotopic composition and latitudinal distribution

    Energy Technology Data Exchange (ETDEWEB)

    Andres, R.J.; Marland, G.; Boden, T.; Bischof, S.

    1994-10-01

    This work briefly discusses four of the current research emphases at Oak Ridge National Laboratory regarding the emission of carbon dioxide (CO{sub 2}) from fossil fuel consumption, natural gas flaring and cement manufacture. These emphases include: (1) updating the 1950 to present time series of CO{sub 2} emissions from fossil fuel consumption and cement manufacture, (2) extending this time series back to 1751, (3) gridding the data at 1{sup 0} by 1{sup 0} resolution, and (4) estimating the isotopic signature of these emissions. In 1991, global emissions of CO{sub 2} from fossil fuel and cement increased 1.5% over 1990 levels to 6188 {times} 10{sup 6} metric tonnes C. The Kuwaiti oil fires can account for all of the increase. Recently published energy data (Etemad et al., 1991) allow extension of the CO emissions time series back to 1751. Preliminary examination shows good agreement with two other, but shorter, energy time series. A latitudinal distribution of carbon emissions is being completed. A southward shift in the major mass of CO{sub 2} emissions is occurring from European-North American latitudes towards central-southeast Asian latitudes, reflecting the growth of population and industrialization at these lower latitudes. The carbon isotopic signature of these emissions has been re-examined. The emissions of the last two decades are approximately 1{per_thousand} lighter than previously reported (Tans, 1981). This lightening of the emissions signature is due to fossil fuel gases and liquids, including a revision of their {delta}{sup 13}C isotopic signature and an increased production rate.

  10. Biogenic CaCO3 and Opal Depositions and Their Latitudinal Comparison During the Past 600 ka in the Central Equatorial Pacific

    Directory of Open Access Journals (Sweden)

    Boo-Keun Khim

    2015-01-01

    Full Text Available The orbital-scale variations in biogenic CaCO3 and opal abundance in two piston cores collected in the central equatorial Pacific (core PC5101 from a southern site at _ and core PC5103 from a northern site at _ were compared to assess latitudinal differences. The correlation between the oxygen isotope stratigraphy of planktonic foraminifera (Globigerinoides sacculifer of PC5103 with the LR04 stacks provides the age of PC5103 to be approximately 950 ka. The age of PC5103 was further refined by correlating the CaCO3 content with the well-dated core RC11-210. The age of PC5101 was also constrained by the same CaCO3 chronostratigraphic correlation with RC11-210, resulting in an age of approximately 650 ka. Distinct orbital-scale series of CaCO3 and opal variations appear to be parallel between the two cores during the past 600 ka, which are controlled mainly by eccentricity with an approximate periodicity of 100 ka. It is worth noting that the biogenic CaCO3 and opal deposition patterns in the two cores differ between interglacial and glacial periods. During interglacial periods the biogenic opal content is higher in the southern core than in the northern core, which corresponds with the present-day condition. In contrast the CaCO3 content is higher in the northern core, which is contradictory to the present-day northward decreasing CaCO3 deposition pattern from the Equator. The collection site of PC5101 is approximately 350 m deeper than that of PC5103, which significantly promotes CaCO3 dissolution and causes unexpectedly high CaCO3 content at the northern site in contrast to the biogenic opal content.

  11. Increasing minimum daily temperatures are associated with enhanced pesticide use in cultivated soybean along a latitudinal gradient in the mid-western United States.

    Directory of Open Access Journals (Sweden)

    Lewis H Ziska

    Full Text Available Assessments of climate change and food security often do not consider changes to crop production as a function of altered pest pressures. Evaluation of potential changes may be difficult, in part, because management practices are routinely utilized in situ to minimize pest injury. If so, then such practices, should, in theory, also change with climate, although this has never been quantified. Chemical (pesticide applications remain the primary means of managing pests in industrialized countries. While a wide range of climate variables can influence chemical use, minimum daily temperature (lowest 24 h recorded temperature in a given year can be associated with the distribution and thermal survival of many agricultural pests in temperate regions. The current study quantifies average pesticide applications since 1999 for commercial soybean grown over a 2100 km North-South latitudinal transect for seven states that varied in minimum daily temperature (1999-2013 from -28.6°C (Minnesota to -5.1°C (Louisiana. Although soybean yields (per hectare did not vary by state, total pesticide applications (kg of active ingredient, ai, per hectare increased from 4.3 to 6.5 over this temperature range. Significant correlations were observed between minimum daily temperatures and kg of ai for all pesticide classes. This suggested that minimum daily temperature could serve as a proxy for pesticide application. Longer term temperature data (1977-2013 indicated greater relative increases in minimum daily temperatures for northern relative to southern states. Using these longer-term trends to determine short-term projections of pesticide use (to 2023 showed a greater comparative increase in herbicide use for soybean in northern; but a greater increase in insecticide and fungicide use for southern states in a warmer climate. Overall, these data suggest that increases in pesticide application rates may be a means to maintain soybean production in response to rising

  12. High density of tree-cavities and snags in tropical dry forest of western Mexico raises questions for a latitudinal gradient.

    Science.gov (United States)

    Vázquez, Leopoldo; Renton, Katherine

    2015-01-01

    It has been suggested that a latitudinal gradient exists of a low density of snags and high density of naturally-formed tree-cavities in tropical vs. temperate forests, though few cavities may have characteristics suitable for nesting by birds. We determined snag and cavity density, characteristics, and suitability for birds in a tropical dry forest biome of western Mexico, and evaluated whether our data fits the trend of snag and cavity density typically found in tropical moist and wet forests. We established five 0.25-ha transects to survey and measure tree-cavities and snags in each of three vegetation types of deciduous, semi-deciduous, and mono-dominant Piranhea mexicana forest, comprising a total of 3.75 ha. We found a high density of 77 cavities/ha, with 37 cavities suitable for birds/ha, where density, and characteristics of cavities varied significantly among vegetation types. Lowest abundance of cavities occurred in deciduous forest, and these were in smaller trees, at a lower height, and with a narrower entrance diameter. Only 8.6% of cavities were excavated by woodpeckers, and only 11% of cavities were occupied, mainly by arthropods, though 52% of all cavities were unsuitable for birds. We also found a high density of 56 snags/ha, with greatest density in deciduous forest (70 snags/ha), though these were of significantly smaller diameter, and snags of larger diameter were more likely to contain cavities. The Chamela-Cuixmala tropical dry forest had the highest density of snags recorded for any tropical or temperate forest, and while snag density was significantly correlated with mean snag dbh, neither latitude nor mean dbh predicted snag density in ten forest sites. The high spatial aggregation of snag and cavity resources in tropical dry forest may limit their availability, particularly for large-bodied cavity adopters, and highlights the importance of habitat heterogeneity in providing resources for primary and secondary cavity-nesters.

  13. Phenological models to predict the main flowering phases of olive ( Olea europaea L.) along a latitudinal and longitudinal gradient across the Mediterranean region

    Science.gov (United States)

    Aguilera, Fátima; Fornaciari, Marco; Ruiz-Valenzuela, Luis; Galán, Carmen; Msallem, Monji; Dhiab, Ali Ben; la Guardia, Consuelo Díaz-de; del Mar Trigo, María; Bonofiglio, Tommaso; Orlandi, Fabio

    2015-05-01

    The aim of the present study was to develop pheno-meteorological models to explain and forecast the main olive flowering phenological phases within the Mediterranean basin, across a latitudinal and longitudinal gradient that includes Tunisia, Spain, and Italy. To analyze the aerobiological sampling points, study periods from 13 years (1999-2011) to 19 years (1993-2011) were used. The forecasting models were constructed using partial least-squares regression, considering both the flowering start and full-flowering dates as dependent variables. The percentages of variance explained by the full-flowering models (mean 84 %) were greater than those explained by the flowering start models (mean 77 %). Moreover, given the time lag from the North African areas to the central Mediterranean areas in the main olive flowering dates, the regional full-flowering predictive models are proposed as the most useful to improve the knowledge of the influence of climate on the olive tree floral phenology. The meteorological parameters related to the previous autumn and both the winter and the spring seasons, and above all the temperatures, regulate the reproductive phenology of olive trees in the Mediterranean area. The mean anticipation of flowering start and full flowering for the future period from 2081 to 2100 was estimated at 10 and 12 days, respectively. One question can be raised: Will the olive trees located in the warmest areas be northward displaced or will they be able to adapt their physiology in response to the higher temperatures? The present study can be considered as an approach to design more detailed future bioclimate research.

  14. The use of coded PCR primers enables high-throughput sequencing of multiple homolog amplification products by 454 parallel sequencing.

    Directory of Open Access Journals (Sweden)

    Jonas Binladen

    2007-02-01

    Full Text Available The invention of the Genome Sequence 20 DNA Sequencing System (454 parallel sequencing platform has enabled the rapid and high-volume production of sequence data. Until now, however, individual emulsion PCR (emPCR reactions and subsequent sequencing runs have been unable to combine template DNA from multiple individuals, as homologous sequences cannot be subsequently assigned to their original sources.We use conventional PCR with 5'-nucleotide tagged primers to generate homologous DNA amplification products from multiple specimens, followed by sequencing through the high-throughput Genome Sequence 20 DNA Sequencing System (GS20, Roche/454 Life Sciences. Each DNA sequence is subsequently traced back to its individual source through 5'tag-analysis.We demonstrate that this new approach enables the assignment of virtually all the generated DNA sequences to the correct source once sequencing anomalies are accounted for (miss-assignment rate<0.4%. Therefore, the method enables accurate sequencing and assignment of homologous DNA sequences from multiple sources in single high-throughput GS20 run. We observe a bias in the distribution of the differently tagged primers that is dependent on the 5' nucleotide of the tag. In particular, primers 5' labelled with a cytosine are heavily overrepresented among the final sequences, while those 5' labelled with a thymine are strongly underrepresented. A weaker bias also exists with regards to the distribution of the sequences as sorted by the second nucleotide of the dinucleotide tags. As the results are based on a single GS20 run, the general applicability of the approach requires confirmation. However, our experiments demonstrate that 5'primer tagging is a useful method in which the sequencing power of the GS20 can be applied to PCR-based assays of multiple homologous PCR products. The new approach will be of value to a broad range of research areas, such as those of comparative genomics, complete mitochondrial

  15. Exploration Medical System Demonstration Project

    Science.gov (United States)

    Chin, D. A.; McGrath, T. L.; Reyna, B.; Watkins, S. D.

    2011-01-01

    A near-Earth Asteroid (NEA) mission will present significant new challenges including hazards to crew health created by exploring a beyond low earth orbit destination, traversing the terrain of asteroid surfaces, and the effects of variable gravity environments. Limited communications with ground-based personnel for diagnosis and consultation of medical events require increased crew autonomy when diagnosing conditions, creating treatment plans, and executing procedures. Scope: The Exploration Medical System Demonstration (EMSD) project will be a test bed on the International Space Station (ISS) to show an end-to-end medical system assisting the Crew Medical Officers (CMO) in optimizing medical care delivery and medical data management during a mission. NEA medical care challenges include resource and resupply constraints limiting the extent to which medical conditions can be treated, inability to evacuate to Earth during many mission phases, and rendering of medical care by a non-clinician. The system demonstrates the integration of medical technologies and medical informatics tools for managing evidence and decision making. Project Objectives: The objectives of the EMSD project are to: a) Reduce and possibly eliminate the time required for a crewmember and ground personnel to manage medical data from one application to another. b) Demonstrate crewmember's ability to access medical data/information via a software solution to assist/aid in the treatment of a medical condition. c) Develop a common data management architecture that can be ubiquitously used to automate repetitive data collection, management, and communications tasks for all crew health and life sciences activities. d) Develop a common data management architecture that allows for scalability, extensibility, and interoperability of data sources and data users. e) Lower total cost of ownership for development and sustainment of peripheral hardware and software that use EMSD for data management f) Provide

  16. AAEC builds synroc demonstration plant

    International Nuclear Information System (INIS)

    O'Hagan, R.

    1986-01-01

    A demonstration plant to test the feasibility of an Australian-developed method of immobilising radioactive waste is being built at the Australian Atomic Energy Commission's Lucas Heights Research Laboratories. The plant will operate as if radioactive waste was actually being processed, but non-radioactive elements of a similar composition will be used. The process involves the simulated waste being mixed into a slurry with the main SYNROC ingredients and then converted to a powder. The powder is moved about the plant in bellows-type containers by robots

  17. Charge sniffer for electrostatics demonstrations

    Science.gov (United States)

    Dinca, Mihai P.

    2011-02-01

    An electronic electroscope with a special design for demonstrations and experiments on static electricity is described. It operates as an electric charge sniffer by detecting slightly charged objects when they are brought to the front of its sensing electrode. The sniffer has the advantage of combining high directional sensitivity with a logarithmic bar display. It allows for the identification of electric charge polarity during charge separation by friction, peeling, electrostatic induction, batteries, or secondary coils of power transformers. Other experiments in electrostatics, such as observing the electric field of an oscillating dipole and the distance dependence of the electric field generated by simple charge configurations, are also described.

  18. Dynamic Underground Stripping Demonstration Project

    International Nuclear Information System (INIS)

    Aines, R.; Newmark, R.; McConachie, W.; Rice, D.; Ramirez, A.; Siegel, W.; Buettner, M.; Daily, W.; Krauter, P.; Folsom, E.; Boegel, A.J.; Bishop, D.; udel, K.

    1992-03-01

    LLNL is collaborating with the UC Berkeley College of Engineering to develop and demonstrate a system of thermal remediation and underground imaging techniques for use in rapid cleanup of localized underground spills. Called ''Dynamic Stripping'' to reflect the rapid and controllable nature of the process, it will combine steam injection, direct electrical heating, and tomographic geophysical imaging in a cleanup of the LLNL gasoline spill. In the first 8 months of the project, a Clean Site engineering test was conducted to prove the field application of the techniques before moving to the contaminated site in FY 92

  19. Adaptive Processing for Sequence Alignment

    KAUST Repository

    Zidan, Mohammed A.; Bonny, Talal; Salama, Khaled N.

    2012-01-01

    Disclosed are various embodiments for adaptive processing for sequence alignment. In one embodiment, among others, a method includes obtaining a query sequence and a plurality of database sequences. A first portion of the plurality of database sequences is distributed to a central processing unit (CPU) and a second portion of the plurality of database sequences is distributed to a graphical processing unit (GPU) based upon a predetermined splitting ratio associated with the plurality of database sequences, where the database sequences of the first portion are shorter than the database sequences of the second portion. A first alignment score for the query sequence is determined with the CPU based upon the first portion of the plurality of database sequences and a second alignment score for the query sequence is determined with the GPU based upon the second portion of the plurality of database sequences.

  20. Adaptive Processing for Sequence Alignment

    KAUST Repository

    Zidan, Mohammed A.

    2012-01-26

    Disclosed are various embodiments for adaptive processing for sequence alignment. In one embodiment, among others, a method includes obtaining a query sequence and a plurality of database sequences. A first portion of the plurality of database sequences is distributed to a central processing unit (CPU) and a second portion of the plurality of database sequences is distributed to a graphical processing unit (GPU) based upon a predetermined splitting ratio associated with the plurality of database sequences, where the database sequences of the first portion are shorter than the database sequences of the second portion. A first alignment score for the query sequence is determined with the CPU based upon the first portion of the plurality of database sequences and a second alignment score for the query sequence is determined with the GPU based upon the second portion of the plurality of database sequences.

  1. Flambeau River Biofuels Demonstration Plant

    Energy Technology Data Exchange (ETDEWEB)

    Byrne, Robert J. [Flambeau River Biofuels, Inc., Park Falls, WI (United States)

    2012-07-30

    Flambeau River BioFuels, Inc. (FRB) proposed to construct a demonstration biomass-to-liquids (BTL) biorefinery in Park Falls, Wisconsin. The biorefinery was to be co-located at the existing pulp and paper mill, Flambeau River Papers, and when in full operation would both generate renewable energy – making Flambeau River Papers the first pulp and paper mill in North America to be nearly fossil fuel free – and produce liquid fuels from abundant and renewable lignocellulosic biomass. The biorefinery would serve to validate the thermochemical pathway and economic models for BTL production using forest residuals and wood waste, providing a basis for proliferating BTL conversion technologies throughout the United States. It was a project goal to create a compelling new business model for the pulp and paper industry, and support the nation’s goal for increasing renewable fuels production and reducing its dependence on foreign oil. FRB planned to replicate this facility at other paper mills after this first demonstration scale plant was operational and had proven technical and economic feasibility.

  2. Parker Hybrid Hydraulic Drivetrain Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Collett, Raymond [Parker-Hannifin Corporation, Cleveland, OH (United States); Howland, James [Parker-Hannifin Corporation, Cleveland, OH (United States); Venkiteswaran, Prasad [National Energy Technology Lab. (NETL), Morgantown, WV (United States)

    2014-03-31

    This report examines the benefits of Parker Hannifin hydraulic hybrid brake energy recovery systems used in commercial applications for vocational purposes. A detailed background on the problem statement being addressed as well as the solution set specific for parcel delivery will be provided. Objectives of the demonstration performed in high start & stop applications included opportunities in fuel usage reduction, emissions reduction, vehicle productivity, and vehicle maintenance. Completed findings during the demonstration period and parallel investigations with NREL, CALSTART, along with a literature review will be provided herein on this research area. Lastly, results identified in the study by third parties validated the savings potential in fuel reduction of on average of 19% to 52% over the baseline in terms of mpg (Lammert, 2014, p11), Parker data for parcel delivery vehicles in the field parallels this at a range of 35% - 50%, emissions reduction of 17.4% lower CO2 per mile and 30.4% lower NOx per mile (Gallo, 2014, p15), with maintenance improvement in the areas of brake and starter replacement, while leaving room for further study in the area of productivity in terms of specific metrics that can be applied and studied.

  3. Reactor-vessel-sectioning demonstration

    International Nuclear Information System (INIS)

    Lundgren, R.A.

    1981-09-01

    A technical demonstration was successfully completed of simulated reactor vessel sectioning using the combined techniques of air arc gouging and flame cutting. A 4-ft x 3-ft x 9-in. thick sample was fabricated of A36 carbon steel to simulate a reactor vessel wall. A 1/4-in. layer of stainless steel (SS) was tungsten inert gas (TIG)-welded to the carbon steel. Several techniques were considered to section the simulated reactor vessel; air arc gouging was selected to penetrate the stainless steel, and flame cutting was selected to sever the carbon steel. Three sectioning operations were demonstrated. For all three, the operating parameters were the same; but the position of the sample was varied. For the first cut, the sample was placed in a horizontal position, and it was successfully severed from the SS side. For the second cut, the sample was turned over and cut from the carbon steel side. Cutting from the carbon steel side has the advantages of cost reduction

  4. Energy 2007. Research, development, demonstration; Energi 07. Forskning, udvikling, demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Byriel, I.P.; Justesen, Helle; Beck, A.; Borup Jensen, J.; Rosenfeldt Jakobsen, Kl; Jacobsen, Steen Hartvig (eds.)

    2007-08-10

    Danish energy research is in an exciting and challenging situation. Rising oil prices, unstable energy supply, climate policy responsibilities and globalization have brought development of new environmentally friendly and more efficient energy technologies into focus. Promising international markets for newly developed energy technologies are emerging, and at the same time well established Danish positions of strength are challenged by new strong actors on the global market. The Danish government has set to work on its vision of an appreciable strengthening of public energy research funding through the recent law on the energy technological development and demonstration programme EUDP and the realization of globalization funds. The interaction between basic and applied research must be kept intact. In this report the various Danish energy research programmes administered by Energinet.dk, Danish Energy Authority, Danish Energy Association, Danish Council for Strategic Research's Programme Commission on Energy and Environment and Danish National Advanced Technology Foundation, coordinate their annual reports for the first time. The aim of Energy 2007 is to give the reader an idea of how the energy research programmes collaborate on solving the major energy technology challenges - also in an international context. (BA)

  5. Main sequence mass loss

    International Nuclear Information System (INIS)

    Brunish, W.M.; Guzik, J.A.; Willson, L.A.; Bowen, G.

    1987-01-01

    It has been hypothesized that variable stars may experience mass loss, driven, at least in part, by oscillations. The class of stars we are discussing here are the δ Scuti variables. These are variable stars with masses between about 1.2 and 2.25 M/sub θ/, lying on or very near the main sequence. According to this theory, high rotation rates enhance the rate of mass loss, so main sequence stars born in this mass range would have a range of mass loss rates, depending on their initial rotation velocity and the amplitude of the oscillations. The stars would evolve rapidly down the main sequence until (at about 1.25 M/sub θ/) a surface convection zone began to form. The presence of this convective region would slow the rotation, perhaps allowing magnetic braking to occur, and thus sharply reduce the mass loss rate. 7 refs

  6. The Liquid Argon Purity Demonstrator

    Energy Technology Data Exchange (ETDEWEB)

    Adamowski, M.; Carls, B.; Dvorak, E.; Hahn, A.; Jaskierny, W.; Johnson, C.; Jostlein, H.; Kendziora, C.; Lockwitz, S.; Pahlka, B.; Plunkett, R.; Pordes, S.; Rebel, B.; Schmitt, R.; Stancari, M.; Tope, T.; Voirin, E.; Yang, T.

    2014-07-01

    The Liquid Argon Purity Demonstrator was an R&D test stand designed to determine if electron drift lifetimes adequate for large neutrino detectors could be achieved without first evacuating the cryostat. We describe here the cryogenic system, its operations, and the apparatus used to determine the contaminant levels in the argon and to measure the electron drift lifetime. The liquid purity obtained by this system was facilitated by a gaseous argon purge. Additionally, gaseous impurities from the ullage were prevented from entering the liquid at the gas-liquid interface by condensing the gas and filtering the resulting liquid before returning to the cryostat. The measured electron drift lifetime in this test was greater than 6 ms, sustained over several periods of many weeks. Measurements of the temperature profile in the argon, to assess convective flow and boiling, were also made and are compared to simulation.

  7. Prototypical Rod Consolidation Demonstration Project

    International Nuclear Information System (INIS)

    1993-05-01

    The objective of Phase 3 of the Prototypical Rod consolidation Demonstration Project (PRCDP) was to procure, fabricate, assemble, and test the Prototypical Rod consolidation System as described in the NUS Phase 2 Final Design Report. This effort required providing the materials, components, and fabricated parts which makes up all of the system equipment. In addition, it included the assembly, installation, and setup of this equipment at the Cold Test Facility. During the Phase 3 effort the system was tested on a component, subsystem, and system level. This volume 1, discusses the PRCDP Phase 3 Test Program that was conducted by the HALLIBURTON NUS Environmental Corporation under contract AC07-86ID12651 with the United States Department of Energy. This document, Volume 1, Book 2 discusses the following topics: Fuel Rod Extraction System Test Results and Analysis Reports and Clamping Table Test Results and Analysis Reports

  8. Prototypical Rod Consolidation Demonstration Project

    International Nuclear Information System (INIS)

    1993-05-01

    The objective of Phase 3 of the Prototypical Rod consolidation Demonstration Project (PRCDP) was to procure, fabricate, assemble, and test the Prototypical Rod consolidation System as described in the NUS Phase 2 Final Design Report. This effort required providing the materials, components, and fabricated parts which makes up all of the system equipment. In addition, it included the assembly, installation, and setup of this equipment at the Cold Test Facility. During the Phase 3 effort the system was tested on a component, subsystem, and system level. This volume 1, discusses the PRCDP Phase 3 Test Program that was conducted by the HALLIBURTON NUS Environmental Corporation under contract AC07-86ID12651 with the United States Department of Energy. This document, Volume 1, Book 1 discusses the following topics: the background of the project; test program description; summary of tests and test results; problem evaluation; functional requirements confirmation; recommendations; and completed test documentation for tests performed in Phase 3

  9. Prototypical Rod Consolidation Demonstration Project

    International Nuclear Information System (INIS)

    1993-05-01

    The objective of Phase III of the Prototypical Rod Consolidation Demonstration Project (PRCDP) was to procure, fabricate, assemble, and test the Prototypical Rod Consolidation System as described in the NUS Phase II Final Design Report. This effort required providing the materials, components, and fabricated parts which makes up all of the system equipment. In addition, it included the assembly, installation, and setup of this equipment at the Cold Test Facility. During the Phase III effort the system was tested on a component, subsystem, and system level. Volume IV provides the Operating and Maintenance Manual for the Prototypical Rod Consolidation System that was installed at the Cold Test Facility. This document, Book 1 of Volume IV, discusses: Process overview functional descriptions; Control system descriptions; Support system descriptions; Maintenance system descriptions; and Process equipment descriptions

  10. Demonstration of creep during filtration

    DEFF Research Database (Denmark)

    Christensen, Morten Lykkegaard; Bugge, Thomas Vistisen; Kirchheiner, Anders Løvenbalk

    The classical filtration theory assumes a unique relationship between the local filter cake porosity and the local effective pressure. For a number of compressible materials, it has however been observed that during the consolidation stage this may not be the case. It has been found...... that the production of filtrate also depends on the characteristic time for the filter cake solids to deform. This is formulated in the Terzaghi-Voigt model in which a secondary consolidation is introduced. The secondary consolidation may be visualized by plots of the relative cake deformation (U) v.s. the square...... root of time. Even more clearly it is demonstrated by plotting the liquid pressure at the cake piston interface v.s. the relative deformation (to be shown). The phenomenon of a secondary consolidation processes is in short called creep. Provided that the secondary consolidation rate is of the same...

  11. Prototypical Rod Consolidation Demonstration Project

    International Nuclear Information System (INIS)

    1993-05-01

    The objective of Phase 3 of the Prototypical Rod consolidation Demonstration Project (PRCDP) was to procure, fabricate, assemble, and test the Prototypical Rod consolidation System as described in the NUS Phase 2 Final Design Report. This effort required providing the materials, components, and fabricated parts which makes up all of the system equipment. In addition, it included the assembly, installation, and setup of this equipment at the Cold Test Facility. During the Phase 3 effort the system was tested on a component, subsystem, and system level. This volume 1, discusses the PRCDP Phase 3 Test Program that was conducted by the HALLIBURTON NUS Environmental Corporation under contract AC07-86ID12651 with the United States Department of Energy. This document, Volume 1, Book 9 discusses the following topics: Integrated System Normal Operations Test Results and Analysis Report; Integrated System Off-Normal Operations Test Results and Analysis Report; and Integrated System Maintenance Operations Test Results and Analysis Report

  12. Clean Coal Diesel Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Robert Wilson

    2006-10-31

    A Clean Coal Diesel project was undertaken to demonstrate a new Clean Coal Technology that offers technical, economic and environmental advantages over conventional power generating methods. This innovative technology (developed to the prototype stage in an earlier DOE project completed in 1992) enables utilization of pre-processed clean coal fuel in large-bore, medium-speed, diesel engines. The diesel engines are conventional modern engines in many respects, except they are specially fitted with hardened parts to be compatible with the traces of abrasive ash in the coal-slurry fuel. Industrial and Municipal power generating applications in the 10 to 100 megawatt size range are the target applications. There are hundreds of such reciprocating engine power-plants operating throughout the world today on natural gas and/or heavy fuel oil.

  13. Alderney 5 complex demonstration project

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, D. [High Performance Energy Systems, Halifax, NS (Canada)

    2008-07-01

    The Halifax Regional Municipality (HRM) is the largest municipality in Atlantic Canada. This presentation described the flagship facility and the energy efficiency retrofit of five HRM-owned buildings called the Alderney 5 complex. The 5 objectives of the demonstration project involved a district-scale cooling project; replacement of chillers with harbour cooling; and replacement of a high exergy system with a low exergy system. Synergies and challenges of the project were also identified. The presentation also referred to borehole thermal energy storage; existing Halifax Harbour cooling; Halifax Harbour temperatures; cold energy geothermal borehole field; and the benefits of advanced concentric boreholes. A project update and progress to date were also provided. The Alderney 5 project represents the first concentric borehole technology for use to store and retrieve cold energy. tabs., figs.

  14. Prototypical Rod Consolidation Demonstration Project

    International Nuclear Information System (INIS)

    1993-05-01

    The objective of Phase 3 of the Prototypical Rod consolidation Demonstration Project (PRCDP) was to procure, fabricate, assemble, and test the Prototypical Rod consolidation System as described in the NUS Phase 2 Final Design Report. This effort required providing the materials, components, and fabricated parts which makes up all of the system equipment. In addition, it included the assembly, installation, and setup of this equipment at the Cold Test Facility. During the Phase 3 effort the system was tested on a component, subsystem, and system level. This volume 1, discusses the PRCDP Phase 3 Test Program that was conducted by the HALLIBURTON NUS Environmental Corporation under contract AC07-86ID12651 with the United States Department of Energy. This document, Volume 1, Book 8 discusses Control System SOT Tests Results and Analysis Report. This is a continuation of Book 7

  15. Deep Space Habitat Concept Demonstrator

    Science.gov (United States)

    Bookout, Paul S.; Smitherman, David

    2015-01-01

    This project will develop, integrate, test, and evaluate Habitation Systems that will be utilized as technology testbeds and will advance NASA's understanding of alternative deep space mission architectures, requirements, and operations concepts. Rapid prototyping and existing hardware will be utilized to develop full-scale habitat demonstrators. FY 2014 focused on the development of a large volume Space Launch System (SLS) class habitat (Skylab Gen 2) based on the SLS hydrogen tank components. Similar to the original Skylab, a tank section of the SLS rocket can be outfitted with a deep space habitat configuration and launched as a payload on an SLS rocket. This concept can be used to support extended stay at the Lunar Distant Retrograde Orbit to support the Asteroid Retrieval Mission and provide a habitat suitable for human missions to Mars.

  16. Navy fuel cell demonstration project.

    Energy Technology Data Exchange (ETDEWEB)

    Black, Billy D.; Akhil, Abbas Ali

    2008-08-01

    This is the final report on a field evaluation by the Department of the Navy of twenty 5-kW PEM fuel cells carried out during 2004 and 2005 at five Navy sites located in New York, California, and Hawaii. The key objective of the effort was to obtain an engineering assessment of their military applications. Particular issues of interest were fuel cell cost, performance, reliability, and the readiness of commercial fuel cells for use as a standalone (grid-independent) power option. Two corollary objectives of the demonstration were to promote technological advances and to improve fuel performance and reliability. From a cost perspective, the capital cost of PEM fuel cells at this stage of their development is high compared to other power generation technologies. Sandia National Laboratories technical recommendation to the Navy is to remain involved in evaluating successive generations of this technology, particularly in locations with greater environmental extremes, and it encourages their increased use by the Navy.

  17. Prototypical Rod Construction Demonstration Project

    International Nuclear Information System (INIS)

    1993-05-01

    The objective of Phase 3 of the Prototypical Rod consolidation Demonstration Project (PRCDP) was to procure, fabricate, assemble, and test the Prototypical Rod consolidation System as described in the NUS Phase 2 Final Design Report. This effort required providing the materials, components, and fabricated parts which makes up all of the system equipment. In addition, it included the assembly, installation, and setup of this equipment at the Cold Test Facility. During the Phase 3 effort the system was tested on a component, subsystem, and system level. This volume 1, discusses the PRCDP Phase 3 Test Program that was conducted by the HALLIBURTON NUS Environmental Corporation under contract AC07-86ID12651 with the United States Department of Energy. This document, Volume 1, Book 3 discusses the following topics: Downender Test Results and Analysis Report; NFBC Canister Upender Test Results and Analysis Report; Fuel Assembly Handling Fixture Test Results and Analysis Report; and Fuel Canister Upender Test Results and Analysis Report

  18. Prototypical Rod Consolidation Demonstration Project

    International Nuclear Information System (INIS)

    1993-05-01

    The objective of Phase III of the Prototypical Rod Consolidation Demonstration Project (PRCDP) was to procure, fabricate, assemble, and test the Prototypical Rod Consolidation System as described in the NUS Phase II Final Design Report. This effort required providing the materials, components, and fabricated parts which makes up all of the system equipment. In addition, it included the assembly, installation, and setup of this equipment at the Cold Test Facility. During the Phase III effort the system was tested on a component, subsystem, and system level. Volume IV provides the Operating and Maintenance Manual for the Prototypical Rod Consolidation System that was installed at the Cold Test Facility. This document, Book 4 of Volume IV, discusses: Off-normal operating and recovery procedures; Emergency response procedures; Troubleshooting procedures; and Preventive maintenance procedures

  19. Reactor-vessel-sectioning demonstration

    International Nuclear Information System (INIS)

    Lundgren, R.A.

    1981-07-01

    A successful technical demonstration of simulated reactor vessel sectioning was completed using the combined techniques of air arc gouging and flame cutting. A 4-ft x 3-ft x 9-in. thick sample was fabricated of A36 carbon steel to simulate a reactor vessel wall. A 1/4-in layer of stainless steel (SS) was tungsten inert gas (TIG)-welded to the carbon steel. Several techniques were considered to section the simulated reactor vessel: an air arc gouger was chosen to penetrate the stainless steel, and flame cutting was selected to sever the carbon steel. After the simulated vessel was successfully cut from the SS side, another cut was made, starting from the carbon steel side. This cut was also successful. Cutting from the carbon steel side has the advantages of cost reduction since the air arc gouging step is eliminated and contamination controlled because the molten metal is blown inward

  20. Performance Demonstration Program Management Plan

    International Nuclear Information System (INIS)

    2005-01-01

    To demonstrate compliance with the Waste Isolation Pilot Plant (WIPP) waste characterization program, each testing and analytical facility performing waste characterization activities participates in the Performance Demonstration Program (PDP). The PDP serves as a quality control check against expected results and provides information about the quality of data generated in the characterization of waste destined for WIPP. Single blind audit samples are prepared and distributed by an independent organization to each of the facilities participating in the PDP. There are three elements within the PDP: analysis of simulated headspace gases, analysis of solids for Resource Conservation and Recovery Act (RCRA) constituents, and analysis for transuranic (TRU) radionuclides using nondestructive assay (NDA) techniques. Because the analysis for TRU radionuclides using NDA techniques involves both the counting of drums and standard waste boxes, four PDP plans are required to describe the activities of the three PDP elements. In accordance with these PDP plans, the reviewing and approving authority for PDP results and for the overall program is the CBFO PDP Appointee. The CBFO PDP Appointee is responsible for ensuring the implementation of each of these plans by concurring with the designation of the Program Coordinator and by providing technical oversight and coordination for the program. The Program Coordinator will designate the PDP Manager, who will coordinate the three elements of the PDP. The purpose of this management plan is to identify how the requirements applicable to the PDP are implemented during the management and coordination of PDP activities. The other participants in the program (organizations that perform site implementation and activities under CBFO contracts or interoffice work orders) are not covered under this management plan. Those activities are governed by the organization's quality assurance (QA) program and procedures or as otherwise directed by CBFO.

  1. Next-generation sequencing of multiple individuals per barcoded library by deconvolution of sequenced amplicons using endonuclease fragment analysis

    DEFF Research Database (Denmark)

    Andersen, Jeppe D; Pereira, Vania; Pietroni, Carlotta

    2014-01-01

    The simultaneous sequencing of samples from multiple individuals increases the efficiency of next-generation sequencing (NGS) while also reducing costs. Here we describe a novel and simple approach for sequencing DNA from multiple individuals per barcode. Our strategy relies on the endonuclease...... digestion of PCR amplicons prior to library preparation, creating a specific fragment pattern for each individual that can be resolved after sequencing. By using both barcodes and restriction fragment patterns, we demonstrate the ability to sequence the human melanocortin 1 receptor (MC1R) genes from 72...... individuals using only 24 barcoded libraries....

  2. Electricity sequence control

    International Nuclear Information System (INIS)

    Shin, Heung Ryeol

    2010-03-01

    The contents of the book are introduction of control system, like classification and control signal, introduction of electricity power switch, such as push-button and detection switch sensor for induction type and capacitance type machinery for control, solenoid valve, expression of sequence and type of electricity circuit about using diagram, time chart, marking and term, logic circuit like Yes, No, and, or and equivalence logic, basic electricity circuit, electricity sequence control, added condition, special program control about choice and jump of program, motor control, extra circuit on repeat circuit, pause circuit in a conveyer, safety regulations and rule about classification of electricity disaster and protective device for insulation.

  3. Demonstration of Data Interactive Publications

    Science.gov (United States)

    Domenico, B.; Weber, J.

    2012-04-01

    This is a demonstration version of the talk given in session ESSI2.4 "Full lifecycle of data." For some years now, the authors have developed examples of online documents that allowed the reader to interact directly with datasets, but there were limitations that restricted the interaction to specific desktop analysis and display tools that were not generally available to all readers of the documents. Recent advances in web service technology and related standards are making it possible to develop systems for publishing online documents that enable readers to access, analyze, and display the data discussed in the publication from the perspective and in the manner from which the author wants it to be represented. By clicking on embedded links, the reader accesses not only the usual textual information in a publication, but also data residing on a local or remote web server as well as a set of processing tools for analyzing and displaying the data. With the option of having the analysis and display processing provided on the server (or in the cloud), there are now a broader set of possibilities on the client side where the reader can interact with the data via a thin web client, a rich desktop application, or a mobile platform "app." The presentation will outline the architecture of data interactive publications along with illustrative examples.

  4. Demonstration poloidal coil test facility

    International Nuclear Information System (INIS)

    Sato, Masahiko; Kawano, Katumi; Tada, Eisuke

    1989-01-01

    A new compact cryogenic cold compressor was developed by Japan Atomic Energy Research Institute (JAERI) in collaboration with Isikawajima-Harima Heavy Industries Co., Ltd. (IHI) in order to produce the supercritical helium below 4.2 K for Demonstration Poloidal Coils (DPC) which are forced-flow cooled type superconducting pulse coils. This compressor is one of key components for DPC test facility. The cold compressor reduces pressure in liquid helium bath, which contains liquid helium of around 3,000 l, down to 0.5 atm efficiently. Consequently, supercritical helium down to 3.5 K is produced and supplied to the DPC coils. A centrifugal compressor with dynamic gas bearing is selected as a compressor mechanism to realize high adiabatic efficiency and large flow rate. In this performance tests, the compressor was operated for 220 h at saturated condition from 0.5 to 1.0 atm without any failure. High adiabatic efficiency (more than 60 %) is achieved with wide flow range (25-65 g/s) and the design value is fully satisfied. The compressor can rotate up to 80,000 rpm at maximum then the coil supply temperature of supercritical helium is 3.5 K. (author)

  5. Demonstration of superconducting micromachined cavities

    Energy Technology Data Exchange (ETDEWEB)

    Brecht, T., E-mail: teresa.brecht@yale.edu; Reagor, M.; Chu, Y.; Pfaff, W.; Wang, C.; Frunzio, L.; Devoret, M. H.; Schoelkopf, R. J. [Department of Applied Physics, Yale University, New Haven, Connecticut 06511 (United States)

    2015-11-09

    Superconducting enclosures will be key components of scalable quantum computing devices based on circuit quantum electrodynamics. Within a densely integrated device, they can protect qubits from noise and serve as quantum memory units. Whether constructed by machining bulk pieces of metal or microfabricating wafers, 3D enclosures are typically assembled from two or more parts. The resulting seams potentially dissipate crossing currents and limit performance. In this letter, we present measured quality factors of superconducting cavity resonators of several materials, dimensions, and seam locations. We observe that superconducting indium can be a low-loss RF conductor and form low-loss seams. Leveraging this, we create a superconducting micromachined resonator with indium that has a quality factor of two million, despite a greatly reduced mode volume. Inter-layer coupling to this type of resonator is achieved by an aperture located under a planar transmission line. The described techniques demonstrate a proof-of-principle for multilayer microwave integrated quantum circuits for scalable quantum computing.

  6. Prototypical Rod Consolidation Demonstration Project

    International Nuclear Information System (INIS)

    1993-05-01

    The objective of Phase 3 of the Prototypical Rod consolidation Demonstration Project (PRCDP) was to procure, fabricate, assemble, and test the Prototypical Rod consolidation System as described in the NUS Phase 2 Final Design Report. This effort required providing the materials, components, and fabricated parts which makes up all of the system equipment. In addition, it included the assembly, installation, and setup of this equipment at the Cold Test Facility. During the Phase 3 effort the system was tested on a component, subsystem, and system level. This volume 1, discusses the PRCDP Phase 3 Test Program that was conducted by the HALLIBURTON NUS Environmental Corporation under contract AC07-86ID12651 with the United States Department of Energy. This document, Volume 1, Book 4 discusses the following topics: Rod Compaction/Loading System Test Results and Analysis Report; Waste Collection System Test Results and Analysis Report; Waste Container Transfer Fixture Test Results and Analysis Report; Staging and Cutting Table Test Results and Analysis Report; and Upper Cutting System Test Results and Analysis Report

  7. Dynamic underground stripping demonstration project

    International Nuclear Information System (INIS)

    Newmark, R.L.

    1992-04-01

    LLNL is collaborating with the UC Berkeley College of Engineering to develop and demonstrate a system of thermal remediation techniques for rapid cleanup of localized underground spills. Called dynamic stripping to reflect the rapid and controllable nature of the process, it will combine steam injection, direct electrical heating, and tomographic geophysical imaging in a cleanup of the LLNL gasoline spill. In the first eight months of the project, a Clean Site engineering test was conducted to prove the field application of the techniques. Tests then began on the contaminated site in FY 1992. This report describes the work at the Clean Site, including design and performance criteria, test results, interpretations, and conclusions. We fielded 'a wide range of new designs and techniques, some successful and some not. In this document, we focus on results and performance, lessons learned, and design and operational changes recommended for work at the contaminated site. Each section focuses on a different aspect of the work and can be considered a self-contained contribution

  8. Prototypical Rod Consolidation Demonstration Project

    International Nuclear Information System (INIS)

    1993-05-01

    The objective of Phase 3 of the Prototypical Rod consolidation Demonstration Project (PRCDP) was to procure, fabricate, assemble, and test the Prototypical Rod consolidation System as described in the NUS Phase 2 Final Design Report. This effort required providing the materials, components, and fabricated parts which makes up all of the system equipment. In addition, it included the assembly, installation, and setup of this equipment at the Cold Test Facility. During the Phase 3 effort the system was tested on a component, subsystem, and system level. This volume 1, discusses the PRCDP Phase 3 Test Program that was conducted by the HALLIBURTON NUS Environmental Corporation under contract AC07-86ID12651 with the United States Department of Energy. This document, Volume 1, Book 5 discusses the following topics: Lower Cutting System Test Results and Analysis Report; NFBC Loading System Test Results and Analysis Report; Robotic Bridge Transporter Test Results and Analysis Report; RM-10A Remotec Manipulator Test Results and Analysis Report; and Manipulator Transporter Test Results and Analysis Report

  9. Ionosphere Waves Service - A demonstration

    Science.gov (United States)

    Crespon, François

    2013-04-01

    In the frame of the FP7 POPDAT project the Ionosphere Waves Service was developed by ionosphere experts to answer several questions: How make the old ionosphere missions more valuable? How provide scientific community with a new insight on wave processes that take place in the ionosphere? The answer is a unique data mining service accessing a collection of topical catalogues that characterize a huge number of Atmospheric Gravity Waves, Travelling Ionosphere Disturbances and Whistlers events. The Ionosphere Waves Service regroups databases of specific events extracted by experts from a ten of ionosphere missions which end users can access by applying specific searches and by using statistical analysis modules for their domain of interest. The scientific applications covered by the IWS are relative to earthquake precursors, ionosphere climatology, geomagnetic storms, troposphere-ionosphere energy transfer, and trans-ionosphere link perturbations. In this presentation we propose to detail the service design, the hardware and software architecture, and the service functions. The service interface and capabilities will be the focus of a demonstration in order to help potential end-users for their first access to the Ionosphere Waves Service portal. This work is made with the support of FP7 grant # 263240.

  10. Biological sequence analysis

    DEFF Research Database (Denmark)

    Durbin, Richard; Eddy, Sean; Krogh, Anders Stærmose

    This book provides an up-to-date and tutorial-level overview of sequence analysis methods, with particular emphasis on probabilistic modelling. Discussed methods include pairwise alignment, hidden Markov models, multiple alignment, profile searches, RNA secondary structure analysis, and phylogene...

  11. THE RHIC SEQUENCER

    International Nuclear Information System (INIS)

    VAN ZEIJTS, J.; DOTTAVIO, T.; FRAK, B.; MICHNOFF, R.

    2001-01-01

    The Relativistic Heavy Ion Collider (RHIC) has a high level asynchronous time-line driven by a controlling program called the ''Sequencer''. Most high-level magnet and beam related issues are orchestrated by this system. The system also plays an important task in coordinated data acquisition and saving. We present the program, operator interface, operational impact and experience

  12. Twin anemia polycythemia sequence

    NARCIS (Netherlands)

    Slaghekke, Femke

    2014-01-01

    In this thesis we describe that Twin Anemia Polycythemia Sequence (TAPS) is a form of chronic feto-fetal transfusion in monochorionic (identical) twins based on a small amount of blood transfusion through very small anastomoses. For the antenatal diagnosis of TAPS, Middle Cerebral Artery – Peak

  13. simple sequence repeat (SSR)

    African Journals Online (AJOL)

    In the present study, 78 mapped simple sequence repeat (SSR) markers representing 11 linkage groups of adzuki bean were evaluated for transferability to mungbean and related Vigna spp. 41 markers amplified characteristic bands in at least one Vigna species. The transferability percentage across the genotypes ranged ...

  14. Cerebellar patients demonstrate preserved implicit knowledge of association strengths in musical sequences.

    Science.gov (United States)

    Tillmann, Barbara; Justus, Timothy; Bigand, Emmanuel

    2008-03-01

    Recent findings suggest the involvement of the cerebellum in perceptual and cognitive tasks. Our study investigated whether cerebellar patients show musical priming based on implicit knowledge of tonal-harmonic music. Participants performed speeded phoneme identification on sung target chords, which were either related or less-related to prime contexts in terms of the tonal-harmonic system. As groups, both cerebellar patients and age-matched controls showed facilitated processing for related targets, as previously observed for healthy young adults. The outcome suggests that an intact cerebellum is not mandatory for accessing implicit knowledge stored in long-term memory and for its influence on perception. One patient showed facilitated processing for less-related targets (suggesting sensory priming). The findings suggest directions for future research on auditory perception in cerebellar patients to further our understanding of cerebellar functions.

  15. Demonstrating the Effectiveness of an Integrated and Intensive Research Methods and Statistics Course Sequence

    Science.gov (United States)

    Pliske, Rebecca M.; Caldwell, Tracy L.; Calin-Jageman, Robert J.; Taylor-Ritzler, Tina

    2015-01-01

    We developed a two-semester series of intensive (six-contact hours per week) behavioral research methods courses with an integrated statistics curriculum. Our approach includes the use of team-based learning, authentic projects, and Excel and SPSS. We assessed the effectiveness of our approach by examining our students' content area scores on the…

  16. Sequence embedding for fast construction of guide trees for multiple sequence alignment

    LENUS (Irish Health Repository)

    Blackshields, Gordon

    2010-05-14

    Abstract Background The most widely used multiple sequence alignment methods require sequences to be clustered as an initial step. Most sequence clustering methods require a full distance matrix to be computed between all pairs of sequences. This requires memory and time proportional to N 2 for N sequences. When N grows larger than 10,000 or so, this becomes increasingly prohibitive and can form a significant barrier to carrying out very large multiple alignments. Results In this paper, we have tested variations on a class of embedding methods that have been designed for clustering large numbers of complex objects where the individual distance calculations are expensive. These methods involve embedding the sequences in a space where the similarities within a set of sequences can be closely approximated without having to compute all pair-wise distances. Conclusions We show how this approach greatly reduces computation time and memory requirements for clustering large numbers of sequences and demonstrate the quality of the clusterings by benchmarking them as guide trees for multiple alignment. Source code is available for download from http:\\/\\/www.clustal.org\\/mbed.tgz.

  17. Distribución latitudinal y batimétrica de las especies más abundantes y frecuentes en la fauna acompañante del camarón del Golfo de California, México

    Directory of Open Access Journals (Sweden)

    CarlosHiram Rábago-Quiroz

    2011-03-01

    Full Text Available Latitudinal and bathymetric distribution of the most abundant and frequent species in the shrimp bycatch from the Gulf of California, Mexico. The Gulf of California is one of the most mega-diverse regions in the world, for which few fishery information is available. We present here latitudinal and bathymetric distribution of the most abundant and frequent bycatch species from the Gulf of California. The samples were obtained from a total of 111 hauls taken during seven research cruises of the closed shrimp season (2002-2005-2007, and also, from research cruises made at depths up to 90m. Due to the high variety species in this experimental shrimp bycatch, only those with highest biological value index (BVI were selected. A total of fifteen species had the highest BVI and represented about 60% of the total abundance. A total of 16 508 organisms were analyzed, representing 243 fish, crustacean, mollusk and echinoderm species. Fish were the most abundant, being the most frequent species: Urobatis halleri, Synodus scituliceps, Diplectrum pacificum, Haemulopsis nitidus and Eucinostomus argenteus. A wide latitudinal distribution of these species along the study area, as well as a bathymetric distribution from 9 to 67m depth, was observed. Two of these species were found at 325m depth. Due to the wide bathymetric distribution obtained, total abundances and sizes for each species by depth strata should be determined, and one can assume that deeper than 25m, the capture of these species decreases, and these areas can be used as natural repopulation areas, for depths where they are mainly captured by the commercial shrimp fishery. Rev. Biol. Trop. 59 (1: 255- 267. Epub 2011 March 01.

  18. Magnetic Launch Assist Demonstration Test

    Science.gov (United States)

    2001-01-01

    This image shows a 1/9 subscale model vehicle clearing the Magnetic Launch Assist System, formerly referred to as the Magnetic Levitation (MagLev), test track during a demonstration test conducted at the Marshall Space Flight Center (MSFC). Engineers at MSFC have developed and tested Magnetic Launch Assist technologies. To launch spacecraft into orbit, a Magnetic Launch Assist System would use magnetic fields to levitate and accelerate a vehicle along a track at very high speeds. Similar to high-speed trains and roller coasters that use high-strength magnets to lift and propel a vehicle a couple of inches above a guideway, a launch-assist system would electromagnetically drive a space vehicle along the track. A full-scale, operational track would be about 1.5-miles long and capable of accelerating a vehicle to 600 mph in 9.5 seconds. This track is an advanced linear induction motor. Induction motors are common in fans, power drills, and sewing machines. Instead of spinning in a circular motion to turn a shaft or gears, a linear induction motor produces thrust in a straight line. Mounted on concrete pedestals, the track is 100-feet long, about 2-feet wide and about 1.5-feet high. The major advantages of launch assist for NASA launch vehicles is that it reduces the weight of the take-off, the landing gear, the wing size, and less propellant resulting in significant cost savings. The US Navy and the British MOD (Ministry of Defense) are planning to use magnetic launch assist for their next generation aircraft carriers as the aircraft launch system. The US Army is considering using this technology for launching target drones for anti-aircraft training.

  19. Coal ash artificial reef demonstration

    International Nuclear Information System (INIS)

    Livingston, R.J.; Brendel, G.F.; Bruzek, D.A.

    1991-01-01

    This experimental project evaluated the use of coal ash to construct artificial reefs. An artificial reef consisting of approximately 33 tons of cement-stabilized coal ash blocks was constructed in approximately 20 feet of water in the Gulf of Mexico approximately 9.3 miles west of Cedar Key, Florida. The project objectives were: (1) demonstrate that a durable coal ash/cement block can be manufactured by commercial block-making machines for use in artificial reefs, and (2) evaluate the possibility that a physically stable and environmentally acceptable coal ash/cement block reef can be constructed as a means of expanding recreational and commercial fisheries. The reef was constructed in February 1988 and biological surveys were made at monthly intervals from May 1988 to April 1989. The project provided information regarding: Development of an optimum design mix, block production and reef construction, chemical composition of block leachate, biological colonization of the reef, potential concentration of metals in the food web associated with the reef, acute bioassays (96-hour LC 50 ). The Cedar Key reef was found to be a habitat that was associated with a relatively rich assemblage of plants and animals. The reef did not appear to be a major source of heavy metals to species at various levels of biological organization. GAI Consultants, Inc (GAI) of Monroeville, Pennsylvania was the prime consultant for the project. The biological monitoring surveys and evaluations were performed by Environmental Planning and Analysis, Inc. of Tallahassee, Florida. The chemical analyses of biological organisms and bioassay elutriates were performed by Savannah Laboratories of Tallahassee, Florida. Florida Power Corporation of St. Petersburg, Florida sponsored the project and supplied ash from their Crystal River Energy Complex

  20. Targeted sequencing of plant genomes

    Science.gov (United States)

    Mark D. Huynh

    2014-01-01

    Next-generation sequencing (NGS) has revolutionized the field of genetics by providing a means for fast and relatively affordable sequencing. With the advancement of NGS, wholegenome sequencing (WGS) has become more commonplace. However, sequencing an entire genome is still not cost effective or even beneficial in all cases. In studies that do not require a whole-...

  1. Almost convergence of triple sequences

    OpenAIRE

    Ayhan Esi; M.Necdet Catalbas

    2013-01-01

    In this paper we introduce and study the concepts of almost convergence and almost Cauchy for triple sequences. Weshow that the set of almost convergent triple sequences of 0's and 1's is of the first category and also almost everytriple sequence of 0's and 1's is not almost convergent.Keywords: almost convergence, P-convergent, triple sequence.

  2. A few Smarandache Integer Sequences

    OpenAIRE

    Ibstedt, Henry

    2010-01-01

    This paper deals with the analysis of a few Smarandache Integer Sequences which first appeared in Properties or the Numbers, F. Smarandache, University or Craiova Archives, 1975. The first four sequences are recurrence generated sequences while the last three are concatenation sequences.

  3. A persistent Holocene wetting trend in arid central Asia, with wettest conditions in the late Holocene, revealed by multi-proxy analyses of loess-paleosol sequences in Xinjiang, China

    Science.gov (United States)

    Chen, Fahu; Jia, Jia; Chen, Jianhui; Li, Guoqiang; Zhang, Xiaojian; Xie, Haichao; Xia, Dunsheng; Huang, Wei; An, Chengbang

    2016-08-01

    There are significant differences in the interpretation of the moisture (precipitation) history of arid central Asia (ACA) during the Holocene, as inferred on one hand from speleothem oxygen isotope records, and on the other from lake sediments. Here we present the results of measurements of climatically-sensitive magnetic properties and soil color from four well-dated loess-paleosol sequences from the northern slopes of the Tienshan Mountains and the Yili River valley, Xinjiang, China, in the core area of ACA. Our results demonstrate that the characteristic Holocene paleosol, indicating relatively moist conditions, generally formed after ∼6 ka (1 ka = 1000 cal yr BP) in the study region, and that the accumulation of unweathered loess prevailed during the early Holocene, indicating a dry climate at that time. The magnetic proxies further reveal a trend of generally increasing moisture since the Last Glacial Maximum, with the wettest climate occurring during the late Holocene. This trend of increasing moisture during the Holocene is representative of the Xinjiang region and possibly of the whole of the core area of ACA, and is in marked contrast both to the mid-Holocene moisture maximum observed in the East Asian summer monsoon region and to the general decrease in the strength of the Indian summer monsoon since the early Holocene. Our findings are supported by the results of a climate simulation which indicate a trend of increasing summer and winter precipitation during the Holocene in the core area of ACA, caused mainly by an increase in the strength of the westerlies effected by an increasing latitudinal insolation gradient and by a negative trend of the Arctic Oscillation (AO) or North Atlantic Oscillation (NAO).

  4. Equatorial paleomagnetic time-averaged field results from 0-5 Ma lavas from Kenya and the latitudinal variation of angular dispersion

    Science.gov (United States)

    Opdyke, Neil D.; Kent, Dennis V.; Huang, Kainian; Foster, David A.; Patel, J. P.

    2010-05-01

    higher dispersion near the equator and the smaller latitudinal gradient in dispersion estimated by Johnson et al. (2008). A new database is presented, and the included studies support a systematic decrease of dispersion from high to low latitudes.

  5. Establishing a framework for comparative analysis of genome sequences

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, A.K.

    1995-06-01

    This paper describes a framework and a high-level language toolkit for comparative analysis of genome sequence alignment The framework integrates the information derived from multiple sequence alignment and phylogenetic tree (hypothetical tree of evolution) to derive new properties about sequences. Multiple sequence alignments are treated as an abstract data type. Abstract operations have been described to manipulate a multiple sequence alignment and to derive mutation related information from a phylogenetic tree by superimposing parsimonious analysis. The framework has been applied on protein alignments to derive constrained columns (in a multiple sequence alignment) that exhibit evolutionary pressure to preserve a common property in a column despite mutation. A Prolog toolkit based on the framework has been implemented and demonstrated on alignments containing 3000 sequences and 3904 columns.

  6. Allele Re-sequencing Technologies

    DEFF Research Database (Denmark)

    Byrne, Stephen; Farrell, Jacqueline Danielle; Asp, Torben

    2013-01-01

    The development of next-generation sequencing technologies has made sequencing an affordable approach for detection of genetic variations associated with various traits. However, the cost of whole genome re-sequencing still remains too high to be feasible for many plant species with large...... alternative to whole genome re-sequencing to identify causative genetic variations in plants. One challenge, however, will be efficient bioinformatics strategies for data handling and analysis from the increasing amount of sequence information....

  7. Multilocus Sequence Typing

    OpenAIRE

    Belén, Ana; Pavón, Ibarz; Maiden, Martin C.J.

    2009-01-01

    Multilocus sequence typing (MLST) was first proposed in 1998 as a typing approach that enables the unambiguous characterization of bacterial isolates in a standardized, reproducible, and portable manner using the human pathogen Neisseria meningitidis as the exemplar organism. Since then, the approach has been applied to a large and growing number of organisms by public health laboratories and research institutions. MLST data, shared by investigators over the world via the Internet, have been ...

  8. Achalasia Carcinoma Sequence

    OpenAIRE

    Makmun, Dadang

    2001-01-01

    We report a case of carcinoma of the esophagus in a 58 years old woman with achalasia, who has been diagnosed since 30 years ago, which initiated by surgical treatment (myotomy) and the symptoms recurred since 3 years ago. According to the progress of the disease, Malignancy was strongly suspected due to prolonged stasis and mucosal irritation caused by achalasia (achalasia carcinoma sequence). Because of these contributing factors for the development of serious complications such as Malignan...

  9. Sequencing BPS spectra

    Energy Technology Data Exchange (ETDEWEB)

    Gukov, Sergei [Walter Burke Institute for Theoretical Physics, California Institute of Technology,1200 E California Blvd, Pasadena, CA 91125 (United States); Max-Planck-Institut für Mathematik,Vivatsgasse 7, D-53111 Bonn (Germany); Nawata, Satoshi [Walter Burke Institute for Theoretical Physics, California Institute of Technology,1200 E California Blvd, Pasadena, CA 91125 (United States); Centre for Quantum Geometry of Moduli Spaces, University of Aarhus,Nordre Ringgade 1, DK-8000 (Denmark); Saberi, Ingmar [Walter Burke Institute for Theoretical Physics, California Institute of Technology,1200 E California Blvd, Pasadena, CA 91125 (United States); Stošić, Marko [CAMGSD, Departamento de Matemática, Instituto Superior Técnico,Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Mathematical Institute SANU,Knez Mihajlova 36, 11000 Belgrade (Serbia); Sułkowski, Piotr [Walter Burke Institute for Theoretical Physics, California Institute of Technology,1200 E California Blvd, Pasadena, CA 91125 (United States); Faculty of Physics, University of Warsaw,ul. Pasteura 5, 02-093 Warsaw (Poland)

    2016-03-02

    This paper provides both a detailed study of color-dependence of link homologies, as realized in physics as certain spaces of BPS states, and a broad study of the behavior of BPS states in general. We consider how the spectrum of BPS states varies as continuous parameters of a theory are perturbed. This question can be posed in a wide variety of physical contexts, and we answer it by proposing that the relationship between unperturbed and perturbed BPS spectra is described by a spectral sequence. These general considerations unify previous applications of spectral sequence techniques to physics, and explain from a physical standpoint the appearance of many spectral sequences relating various link homology theories to one another. We also study structural properties of colored HOMFLY homology for links and evaluate Poincaré polynomials in numerous examples. Among these structural properties is a novel “sliding” property, which can be explained by using (refined) modular S-matrix. This leads to the identification of modular transformations in Chern-Simons theory and 3d N=2 theory via the 3d/3d correspondence. Lastly, we introduce the notion of associated varieties as classical limits of recursion relations of colored superpolynomials of links, and study their properties.

  10. Sequencing BPS spectra

    International Nuclear Information System (INIS)

    Gukov, Sergei; Nawata, Satoshi; Saberi, Ingmar; Stošić, Marko; Sułkowski, Piotr

    2016-01-01

    This paper provides both a detailed study of color-dependence of link homologies, as realized in physics as certain spaces of BPS states, and a broad study of the behavior of BPS states in general. We consider how the spectrum of BPS states varies as continuous parameters of a theory are perturbed. This question can be posed in a wide variety of physical contexts, and we answer it by proposing that the relationship between unperturbed and perturbed BPS spectra is described by a spectral sequence. These general considerations unify previous applications of spectral sequence techniques to physics, and explain from a physical standpoint the appearance of many spectral sequences relating various link homology theories to one another. We also study structural properties of colored HOMFLY homology for links and evaluate Poincaré polynomials in numerous examples. Among these structural properties is a novel “sliding” property, which can be explained by using (refined) modular S-matrix. This leads to the identification of modular transformations in Chern-Simons theory and 3d N=2 theory via the 3d/3d correspondence. Lastly, we introduce the notion of associated varieties as classical limits of recursion relations of colored superpolynomials of links, and study their properties.

  11. Image sequence analysis

    CERN Document Server

    1981-01-01

    The processing of image sequences has a broad spectrum of important applica­ tions including target tracking, robot navigation, bandwidth compression of TV conferencing video signals, studying the motion of biological cells using microcinematography, cloud tracking, and highway traffic monitoring. Image sequence processing involves a large amount of data. However, because of the progress in computer, LSI, and VLSI technologies, we have now reached a stage when many useful processing tasks can be done in a reasonable amount of time. As a result, research and development activities in image sequence analysis have recently been growing at a rapid pace. An IEEE Computer Society Workshop on Computer Analysis of Time-Varying Imagery was held in Philadelphia, April 5-6, 1979. A related special issue of the IEEE Transactions on Pattern Anal­ ysis and Machine Intelligence was published in November 1980. The IEEE Com­ puter magazine has also published a special issue on the subject in 1981. The purpose of this book ...

  12. A Forceful Demonstration by FORS

    Science.gov (United States)

    1998-09-01

    .). In addition, detailed computer software was provided to prepare the complex astronomical observations with FORS in advance and to monitor the instrument performance by quality checks of the scientific data accumulated. In return for building FORS for the community of European astrophysicists, the scientists in the three institutions of the FORS Consortium have received a certain amount of Guaranteed Observing Time at the VLT. This time will be used for various research projects concerned, among others, with minor bodies in the outer solar system, stars at late stages of their evolution and the clouds of gas they eject, as well as galaxies and quasars at very large distances, thereby permitting a look-back towards the early epoch of the universe. First tests of FORS1 at the VLT UT1: a great success After careful preparation, the FORS consortium has now started the so-called commissioning of the instrument. This comprises the thorough verification of the specified instrument properties at the telescope, checking the correct functioning under software control from the Paranal control room and, at the end of this process, a demonstration that the instrument fulfills its scientific purpose as planned. While performing these tests, the commissioning team at Paranal were able to obtain images of various astronomical objects, some of which are shown here. Two of these were obtained on the night of "FORS First Light". The photos demonstrate some of the impressive posibilities with this new instrument. They are based on observations with the FORS standard resolution collimator (field size 6.8 x 6.8 armin = 2048 x 2048 pixels; 1 pixel = 0.20 arcsec). Spiral galaxy NGC 1288 ESO PR Photo 37a/98 ESO PR Photo 37a/98 [Preview - JPEG: 800 x 908 pix - 224k] [High-Res - JPEG: 3000 x 3406 pix - 1.5Mb] A colour image of spiral galaxy NGC 1288, obtained on the night of "FORS First Light". The first photo shows a reproduction of a colour composite image of the beautiful spiral galaxy NGC

  13. Foundations of Sequence-to-Sequence Modeling for Time Series

    OpenAIRE

    Kuznetsov, Vitaly; Mariet, Zelda

    2018-01-01

    The availability of large amounts of time series data, paired with the performance of deep-learning algorithms on a broad class of problems, has recently led to significant interest in the use of sequence-to-sequence models for time series forecasting. We provide the first theoretical analysis of this time series forecasting framework. We include a comparison of sequence-to-sequence modeling to classical time series models, and as such our theory can serve as a quantitative guide for practiti...

  14. Novel expressed sequence tag- simple sequence repeats (EST ...

    African Journals Online (AJOL)

    Using different bioinformatic criteria, the SUCEST database was used to mine for simple sequence repeat (SSR) markers. Among 42,189 clusters, 1,425 expressed sequence tag- simple sequence repeats (EST-SSRs) were identified in silico. Trinucleotide repeats were the most abundant SSRs detected. Of 212 primer pairs ...

  15. Infinite sequences and series

    CERN Document Server

    Knopp, Konrad

    1956-01-01

    One of the finest expositors in the field of modern mathematics, Dr. Konrad Knopp here concentrates on a topic that is of particular interest to 20th-century mathematicians and students. He develops the theory of infinite sequences and series from its beginnings to a point where the reader will be in a position to investigate more advanced stages on his own. The foundations of the theory are therefore presented with special care, while the developmental aspects are limited by the scope and purpose of the book. All definitions are clearly stated; all theorems are proved with enough detail to ma

  16. SNAD: sequence name annotation-based designer

    Directory of Open Access Journals (Sweden)

    Gorbalenya Alexander E

    2009-08-01

    Full Text Available Abstract Background A growing diversity of biological data is tagged with unique identifiers (UIDs associated with polynucleotides and proteins to ensure efficient computer-mediated data storage, maintenance, and processing. These identifiers, which are not informative for most people, are often substituted by biologically meaningful names in various presentations to facilitate utilization and dissemination of sequence-based knowledge. This substitution is commonly done manually that may be a tedious exercise prone to mistakes and omissions. Results Here we introduce SNAD (Sequence Name Annotation-based Designer that mediates automatic conversion of sequence UIDs (associated with multiple alignment or phylogenetic tree, or supplied as plain text list into biologically meaningful names and acronyms. This conversion is directed by precompiled or user-defined templates that exploit wealth of annotation available in cognate entries of external databases. Using examples, we demonstrate how this tool can be used to generate names for practical purposes, particularly in virology. Conclusion A tool for controllable annotation-based conversion of sequence UIDs into biologically meaningful names and acronyms has been developed and placed into service, fostering links between quality of sequence annotation, and efficiency of communication and knowledge dissemination among researchers.

  17. Radial and latitudinal dependencies of discontinuities in the solar wind between 0.3 and 19 AU and −80° and +10°

    Directory of Open Access Journals (Sweden)

    A. Söding

    2001-07-01

    Full Text Available Directional discontinuities (DD from 5 missions at 7 different locations between 0.3 and 19 AU and −80° and +10° in the 3D heliosphere are investigated during minimum solar activity. The data are surveyed using the identification criteria of Burlaga (1969 (B and Tsurutani and Smith (1979 (TS. The rate of occurrence depends linearly on the solar wind velocity caused by the geometric effect of investigating a larger plasma volume if the solar wind velocity νsw increases. The radial dependence is proportional to r–0.78 (TS criterion and r–1.28 (B criterion, respectively. This dependence is not only due to an increasing miss rate with increasing distance. The DDs must be unstable or some other physical effect must exist. After normalization of the daily rates to 400 km/s and 1 AU, no dependence on heliographic latitude or on solar wind structures is observable. This means that the DDs are uniformly distributed on a spherical shell. Normalized 64 DD per day are identified with both criteria. But large variations of the daily rate still occur, indicating that other influences must exist. The ratio of the rates of rotational (RDs and tangential discontinuities (TDs depends on the solar wind structures. In high speed streams, relatively more RDs exist than in low speed streams. In the inner heliosphere (r < 10 AU, no radial or latitudinal dependence of the portions of the DD types occur. 55% clear RDs, 10% clear TDs and 33% EDs (either discontinuities are observed, but the portions differ with regard to the criteria used. In the middle heliosphere (10 AU< r < 40 AU, the DD types are more uniformly distributed. The distribution of the directional change ω over the transition evolves to an increase of smaller ω with increasing distance from the sun. The evolution is yielded by the anisotropic RDs with small ω. The spatial thickness dkm in kilometers increases with distance. The thickness drg normalized to the proton gyro radius decreases by a

  18. Reconstruction of precipitation variability in the Strait of Yucatan associated with latitudinal shifts in the position of the Intertropical Convergence Zone since the Last Glacial Maximum

    Science.gov (United States)

    Staines-Urías, Francisca; Seidenkrantz, Marit-Solveig; Fischel, Andrea; Kuijpers, Antoon

    2017-04-01

    The elemental composition of sediments from gravity core HOLOVAR11-03 provides a ca. 40 ka record of past climate variability in the Strait of Yucatan, between the Caribbean Sea and the Gulf of Mexico, a region where precipitation variability is determined by the seasonal position of the Intertropical Convergence Zone (ITCZ). Within this region, sea level pressure decreases and rainfall increases as the ITCZ moves north of the equator in response to increased solar insolation in the Northern Hemisphere during boreal summer. In contrast, as the ITCZ retracts southward towards the equator during boreal winter, rainfall diminishes and the regional sea level pressure gradient strengthens. On interannual, multidecadal and millennial timescales, fluctuations in the average latitudinal position of the ITCZ in response to insolation forcing modulate the intensity and duration of the seasonal regimens, determining average regional precipitation and, ultimately, the elemental composition of the marine sedimentary record. Regionally, higher titanium and iron content in marine sediments reflect greater terrigenous input from inland runoff, indicating greater precipitation, hence a more northerly position of the ITCZ. Correspondingly, Ti and Fe concentration data were used to reconstruct regional rainfall variability since the Last Glacial Maxima (LGM ˜24 cal ka BP). HOLOVAR11-03 age model (based on 4 AMS 14C dates obtained from multi-specific samples of planktic foraminifera) shows stable sedimentation rates in the area throughout the cored period. Nonetheless, higher terrestrial mineral input is observed since the LGM and all through the last glacial termination (24 to 12 cal ka BP), indicating a period of increased precipitation. In contrast, lower Ti and Fe values are typical for the period between 12 and 8 cal ka BP, indicating reduced precipitation. A positive trend characterizes the following interval, showing a return to wetter conditions lasting until 5 cal ka BP

  19. Efeito do gradiente altitudinal/latitudinal sobre espécies de aves florestais da família Furnariidae na Bacia do Rio Tibagi, Paraná, Brasil Effect of altitudinal/latitudinal gradient about forest ovenbirds species (Aves: Furnariidae in the Tibagi river basin, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Fernando de L. Fávaro

    2006-03-01

    Full Text Available Variações na riqueza e abundância de Furnariidae florestais foram analisadas ao longo do gradiente altitudinal/latitudinal da bacia do rio Tibagi (BRT, Paraná, Brasil. A Floresta Ombrófila Mista (1060 m a.n.m. é a formação dominante no sul da BRT, enquanto que a Floresta Estacional Semidecidual (298 m a.n.m., ocorre no norte. O número total de espécies obtidas na BRT foi 14. A riqueza e a abundância de Furnariidae foram maiores no sul (12 espécies, IPA = 2,01 do que no norte (cinco espécies, IPA = 0,45 da BRT. As similaridades também foram altas entre o sul e o centro da BRT. A estrutura da comunidade de Furnariidae também apresentou correlação positiva entre o sul e o centro da BRT (coeficiente de correlação por postos de Spearman; r s = 0,96, r s = 0,89, r s = 1,00. As relações evolutivas de alguns representantes de Furnariidae com o sul da América do Sul e com os Andes podem explicar a maior presença desta família no sul da BRT. Um outro aspecto que também pode ajudar a explicar os resultados apresentados por Furnariidae são as semelhanças entre a Floresta Ombrófila Mista do sul da BRT e outras florestas temperadas da América do Sul.Variations in richness and abundance of forest ovenbirds (Aves: Furnariidae were studied along an altitudinal/latitudinal gradient of the Tibagi river basin (TRB, southern Brazil. Mixed Temperate Rain Forest (1060 m a.s.l. is the dominant forest in the southern TRB while Seasonal Semideciduous Forest (298 m a.s.l. occurs in the northern. The total number of species obtained in the TRB was 14. Richness and Abundance of Furnariidae were greater in the southern (12 species, IPA = 2.01 than in the northern (five species, IPA = 0.45 TRB. Similarities were also greatest in the southern and in the middle TRB. The community structure of Furnariidae also presented a positive correlation between the southern and the middle TRB (Spearman's rank correlation coefficient; r s = 0.96, r s = 0.89, r s

  20. Fast global sequence alignment technique

    KAUST Repository

    Bonny, Mohamed Talal; Salama, Khaled N.

    2011-01-01

    fast alignment algorithm, called 'Alignment By Scanning' (ABS), to provide an approximate alignment of two DNA sequences. We compare our algorithm with the wellknown sequence alignment algorithms, the 'GAP' (which is heuristic) and the 'Needleman

  1. Next-Generation Sequencing Platforms

    Science.gov (United States)

    Mardis, Elaine R.

    2013-06-01

    Automated DNA sequencing instruments embody an elegant interplay among chemistry, engineering, software, and molecular biology and have built upon Sanger's founding discovery of dideoxynucleotide sequencing to perform once-unfathomable tasks. Combined with innovative physical mapping approaches that helped to establish long-range relationships between cloned stretches of genomic DNA, fluorescent DNA sequencers produced reference genome sequences for model organisms and for the reference human genome. New types of sequencing instruments that permit amazing acceleration of data-collection rates for DNA sequencing have been developed. The ability to generate genome-scale data sets is now transforming the nature of biological inquiry. Here, I provide an historical perspective of the field, focusing on the fundamental developments that predated the advent of next-generation sequencing instruments and providing information about how these instruments work, their application to biological research, and the newest types of sequencers that can extract data from single DNA molecules.

  2. Rapid Polymer Sequencer

    Science.gov (United States)

    Stolc, Viktor (Inventor); Brock, Matthew W (Inventor)

    2013-01-01

    Method and system for rapid and accurate determination of each of a sequence of unknown polymer components, such as nucleic acid components. A self-assembling monolayer of a selected substance is optionally provided on an interior surface of a pipette tip, and the interior surface is immersed in a selected liquid. A selected electrical field is impressed in a longitudinal direction, or in a transverse direction, in the tip region, a polymer sequence is passed through the tip region, and a change in an electrical current signal is measured as each polymer component passes through the tip region. Each of the measured changes in electrical current signals is compared with a database of reference electrical change signals, with each reference signal corresponding to an identified polymer component, to identify the unknown polymer component with a reference polymer component. The nanopore preferably has a pore inner diameter of no more than about 40 nm and is prepared by heating and pulling a very small section of a glass tubing.

  3. The advantages of SMRT sequencing

    OpenAIRE

    Roberts, Richard J; Carneiro, Mauricio O; Schatz, Michael C

    2013-01-01

    Of the current next-generation sequencing technologies, SMRT sequencing is sometimes overlooked. However, attributes such as long reads, modified base detection and high accuracy make SMRT a useful technology and an ideal approach to the complete sequencing of small genomes.

  4. Putting instruction sequences into effect

    NARCIS (Netherlands)

    Bergstra, J.A.

    2011-01-01

    An attempt is made to define the concept of execution of an instruction sequence. It is found to be a special case of directly putting into effect of an instruction sequence. Directly putting into effect of an instruction sequences comprises interpretation as well as execution. Directly putting into

  5. Region segmentation along image sequence

    International Nuclear Information System (INIS)

    Monchal, L.; Aubry, P.

    1995-01-01

    A method to extract regions in sequence of images is proposed. Regions are not matched from one image to the following one. The result of a region segmentation is used as an initialization to segment the following and image to track the region along the sequence. The image sequence is exploited as a spatio-temporal event. (authors). 12 refs., 8 figs

  6. Image encryption using random sequence generated from generalized information domain

    International Nuclear Information System (INIS)

    Zhang Xia-Yan; Wu Jie-Hua; Zhang Guo-Ji; Li Xuan; Ren Ya-Zhou

    2016-01-01

    A novel image encryption method based on the random sequence generated from the generalized information domain and permutation–diffusion architecture is proposed. The random sequence is generated by reconstruction from the generalized information file and discrete trajectory extraction from the data stream. The trajectory address sequence is used to generate a P-box to shuffle the plain image while random sequences are treated as keystreams. A new factor called drift factor is employed to accelerate and enhance the performance of the random sequence generator. An initial value is introduced to make the encryption method an approximately one-time pad. Experimental results show that the random sequences pass the NIST statistical test with a high ratio and extensive analysis demonstrates that the new encryption scheme has superior security. (paper)

  7. Didactic demonstrations of superfluidity and superconductivity phenomena

    International Nuclear Information System (INIS)

    Aniola-Jedrzejak, L.; Lewicki, A.; Pilipowicz, A.; Tarnawski, Z.; Bialek, H.

    1980-01-01

    In order to demonstrate to students phenomena of superfluidity and superconductivity a special helium cryostat has been constructed. The demonstrated effects, construction of the cryostat and the method of demonstration are described. (author)

  8. Sequence modelling and an extensible data model for genomic database

    Energy Technology Data Exchange (ETDEWEB)

    Li, Peter Wei-Der [California Univ., San Francisco, CA (United States); Univ. of California, Berkeley, CA (United States)

    1992-01-01

    The Human Genome Project (HGP) plans to sequence the human genome by the beginning of the next century. It will generate DNA sequences of more than 10 billion bases and complex marker sequences (maps) of more than 100 million markers. All of these information will be stored in database management systems (DBMSs). However, existing data models do not have the abstraction mechanism for modelling sequences and existing DBMS`s do not have operations for complex sequences. This work addresses the problem of sequence modelling in the context of the HGP and the more general problem of an extensible object data model that can incorporate the sequence model as well as existing and future data constructs and operators. First, we proposed a general sequence model that is application and implementation independent. This model is used to capture the sequence information found in the HGP at the conceptual level. In addition, abstract and biological sequence operators are defined for manipulating the modelled sequences. Second, we combined many features of semantic and object oriented data models into an extensible framework, which we called the ``Extensible Object Model``, to address the need of a modelling framework for incorporating the sequence data model with other types of data constructs and operators. This framework is based on the conceptual separation between constructors and constraints. We then used this modelling framework to integrate the constructs for the conceptual sequence model. The Extensible Object Model is also defined with a graphical representation, which is useful as a tool for database designers. Finally, we defined a query language to support this model and implement the query processor to demonstrate the feasibility of the extensible framework and the usefulness of the conceptual sequence model.

  9. Sequence modelling and an extensible data model for genomic database

    Energy Technology Data Exchange (ETDEWEB)

    Li, Peter Wei-Der (California Univ., San Francisco, CA (United States) Lawrence Berkeley Lab., CA (United States))

    1992-01-01

    The Human Genome Project (HGP) plans to sequence the human genome by the beginning of the next century. It will generate DNA sequences of more than 10 billion bases and complex marker sequences (maps) of more than 100 million markers. All of these information will be stored in database management systems (DBMSs). However, existing data models do not have the abstraction mechanism for modelling sequences and existing DBMS's do not have operations for complex sequences. This work addresses the problem of sequence modelling in the context of the HGP and the more general problem of an extensible object data model that can incorporate the sequence model as well as existing and future data constructs and operators. First, we proposed a general sequence model that is application and implementation independent. This model is used to capture the sequence information found in the HGP at the conceptual level. In addition, abstract and biological sequence operators are defined for manipulating the modelled sequences. Second, we combined many features of semantic and object oriented data models into an extensible framework, which we called the Extensible Object Model'', to address the need of a modelling framework for incorporating the sequence data model with other types of data constructs and operators. This framework is based on the conceptual separation between constructors and constraints. We then used this modelling framework to integrate the constructs for the conceptual sequence model. The Extensible Object Model is also defined with a graphical representation, which is useful as a tool for database designers. Finally, we defined a query language to support this model and implement the query processor to demonstrate the feasibility of the extensible framework and the usefulness of the conceptual sequence model.

  10. Log-balanced combinatorial sequences

    Directory of Open Access Journals (Sweden)

    Tomislav Došlic

    2005-01-01

    Full Text Available We consider log-convex sequences that satisfy an additional constraint imposed on their rate of growth. We call such sequences log-balanced. It is shown that all such sequences satisfy a pair of double inequalities. Sufficient conditions for log-balancedness are given for the case when the sequence satisfies a two- (or more- term linear recurrence. It is shown that many combinatorially interesting sequences belong to this class, and, as a consequence, that the above-mentioned double inequalities are valid for all of them.

  11. Sequence memory based on coherent spin-interaction neural networks.

    Science.gov (United States)

    Xia, Min; Wong, W K; Wang, Zhijie

    2014-12-01

    Sequence information processing, for instance, the sequence memory, plays an important role on many functions of brain. In the workings of the human brain, the steady-state period is alterable. However, in the existing sequence memory models using heteroassociations, the steady-state period cannot be changed in the sequence recall. In this work, a novel neural network model for sequence memory with controllable steady-state period based on coherent spininteraction is proposed. In the proposed model, neurons fire collectively in a phase-coherent manner, which lets a neuron group respond differently to different patterns and also lets different neuron groups respond differently to one pattern. The simulation results demonstrating the performance of the sequence memory are presented. By introducing a new coherent spin-interaction sequence memory model, the steady-state period can be controlled by dimension parameters and the overlap between the input pattern and the stored patterns. The sequence storage capacity is enlarged by coherent spin interaction compared with the existing sequence memory models. Furthermore, the sequence storage capacity has an exponential relationship to the dimension of the neural network.

  12. Universal sequence map (USM of arbitrary discrete sequences

    Directory of Open Access Journals (Sweden)

    Almeida Jonas S

    2002-02-01

    Full Text Available Abstract Background For over a decade the idea of representing biological sequences in a continuous coordinate space has maintained its appeal but not been fully realized. The basic idea is that any sequence of symbols may define trajectories in the continuous space conserving all its statistical properties. Ideally, such a representation would allow scale independent sequence analysis – without the context of fixed memory length. A simple example would consist on being able to infer the homology between two sequences solely by comparing the coordinates of any two homologous units. Results We have successfully identified such an iterative function for bijective mappingψ of discrete sequences into objects of continuous state space that enable scale-independent sequence analysis. The technique, named Universal Sequence Mapping (USM, is applicable to sequences with an arbitrary length and arbitrary number of unique units and generates a representation where map distance estimates sequence similarity. The novel USM procedure is based on earlier work by these and other authors on the properties of Chaos Game Representation (CGR. The latter enables the representation of 4 unit type sequences (like DNA as an order free Markov Chain transition table. The properties of USM are illustrated with test data and can be verified for other data by using the accompanying web-based tool:http://bioinformatics.musc.edu/~jonas/usm/. Conclusions USM is shown to enable a statistical mechanics approach to sequence analysis. The scale independent representation frees sequence analysis from the need to assume a memory length in the investigation of syntactic rules.

  13. Global patterns in seasonal activity of influenza A/H3N2, A/H1N1, and B from 1997 to 2005: viral coexistence and latitudinal gradients.

    Directory of Open Access Journals (Sweden)

    Brian S Finkelman

    Full Text Available Despite a mass of research on the epidemiology of seasonal influenza, overall patterns of infection have not been fully described on broad geographic scales and for specific types and subtypes of the influenza virus. Here we provide a descriptive analysis of laboratory-confirmed influenza surveillance data by type and subtype (A/H3N2, A/H1N1, and B for 19 temperate countries in the Northern and Southern hemispheres from 1997 to 2005, compiled from a public database maintained by WHO (FluNet. Key findings include patterns of large scale co-occurrence of influenza type A and B, interhemispheric synchrony for subtype A/H3N2, and latitudinal gradients in epidemic timing for type A. These findings highlight the need for more countries to conduct year-round viral surveillance and report reliable incidence data at the type and subtype level, especially in the Tropics.

  14. Distribuição Geográfica e Dispersão Alti-latitudinal de Alguns Gêneros e Espécies da Tribo Triatomini Jeannel, 1919 (Hemiptera, Reduviidae, Triatominae

    Directory of Open Access Journals (Sweden)

    Galvão Cleber

    1998-01-01

    Full Text Available Geographical Distribution and Alti-latitudinal Dispersion of Some Genera and Species of the Tribe Triatomini Jeannel, 1919 (Hemiptera, Reduviidae, Triatominae - With the currently known distribution of genera and species of the tribe Triatomini Jeannel, 1919, maps and diagrams were prepared, showing the geographical area occupied by the species and their respective dispersion in grades of latitude and altitude. Two genera are not treated: Panstrongylus Berg, 1879, already published and Triatoma Laporte, 1832, that is being published partially in several articles. Genus Eratyrus Stal, 1859, has two species, while Dipetalogaster Usinger, 1939, Mepraia Mazza, Gajardo & Joerg, 1940, Paratriatoma Barber, 1938 and recently created genus Hermanlentia Jurberg & Galvão, 1997, have only one each. The study of these maps and diagrams permits a better knowledge about some ecological requirements of Chagas' disease vectors and detects gaps in the geographical distribution, where the species were not found but probably they could be prevalent

  15. Biomolecule Sequencer: Next-Generation DNA Sequencing Technology for In-Flight Environmental Monitoring, Research, and Beyond

    Science.gov (United States)

    Smith, David J.; Burton, Aaron; Castro-Wallace, Sarah; John, Kristen; Stahl, Sarah E.; Dworkin, Jason Peter; Lupisella, Mark L.

    2016-01-01

    On the International Space Station (ISS), technologies capable of rapid microbial identification and disease diagnostics are not currently available. NASA still relies upon sample return for comprehensive, molecular-based sample characterization. Next-generation DNA sequencing is a powerful approach for identifying microorganisms in air, water, and surfaces onboard spacecraft. The Biomolecule Sequencer payload, manifested to SpaceX-9 and scheduled on the Increment 4748 research plan (June 2016), will assess the functionality of a commercially-available next-generation DNA sequencer in the microgravity environment of ISS. The MinION device from Oxford Nanopore Technologies (Oxford, UK) measures picoamp changes in electrical current dependent on nucleotide sequences of the DNA strand migrating through nanopores in the system. The hardware is exceptionally small (9.5 x 3.2 x 1.6 cm), lightweight (120 grams), and powered only by a USB connection. For the ISS technology demonstration, the Biomolecule Sequencer will be powered by a Microsoft Surface Pro3. Ground-prepared samples containing lambda bacteriophage, Escherichia coli, and mouse genomic DNA, will be launched and stored frozen on the ISS until experiment initiation. Immediately prior to sequencing, a crew member will collect and thaw frozen DNA samples, connect the sequencer to the Surface Pro3, inject thawed samples into a MinION flow cell, and initiate sequencing. At the completion of the sequencing run, data will be downlinked for ground analysis. Identical, synchronous ground controls will be used for data comparisons to determine sequencer functionality, run-time sequence, current dynamics, and overall accuracy. We will present our latest results from the ISS flight experiment the first time DNA has ever been sequenced in space and discuss the many potential applications of the Biomolecule Sequencer for environmental monitoring, medical diagnostics, higher fidelity and more adaptable Space Biology Human

  16. International interlaboratory study comparing single organism 16S rRNA gene sequencing data: Beyond consensus sequence comparisons

    Science.gov (United States)

    Olson, Nathan D.; Lund, Steven P.; Zook, Justin M.; Rojas-Cornejo, Fabiola; Beck, Brian; Foy, Carole; Huggett, Jim; Whale, Alexandra S.; Sui, Zhiwei; Baoutina, Anna; Dobeson, Michael; Partis, Lina; Morrow, Jayne B.

    2015-01-01

    This study presents the results from an interlaboratory sequencing study for which we developed a novel high-resolution method for comparing data from different sequencing platforms for a multi-copy, paralogous gene. The combination of PCR amplification and 16S ribosomal RNA gene (16S rRNA) sequencing has revolutionized bacteriology by enabling rapid identification, frequently without the need for culture. To assess variability between laboratories in sequencing 16S rRNA, six laboratories sequenced the gene encoding the 16S rRNA from Escherichia coli O157:H7 strain EDL933 and Listeria monocytogenes serovar 4b strain NCTC11994. Participants performed sequencing methods and protocols available in their laboratories: Sanger sequencing, Roche 454 pyrosequencing®, or Ion Torrent PGM®. The sequencing data were evaluated on three levels: (1) identity of biologically conserved position, (2) ratio of 16S rRNA gene copies featuring identified variants, and (3) the collection of variant combinations in a set of 16S rRNA gene copies. The same set of biologically conserved positions was identified for each sequencing method. Analytical methods using Bayesian and maximum likelihood statistics were developed to estimate variant copy ratios, which describe the ratio of nucleotides at each identified biologically variable position, as well as the likely set of variant combinations present in 16S rRNA gene copies. Our results indicate that estimated variant copy ratios at biologically variable positions were only reproducible for high throughput sequencing methods. Furthermore, the likely variant combination set was only reproducible with increased sequencing depth and longer read lengths. We also demonstrate novel methods for evaluating variable positions when comparing multi-copy gene sequence data from multiple laboratories generated using multiple sequencing technologies. PMID:27077030

  17. International interlaboratory study comparing single organism 16S rRNA gene sequencing data: Beyond consensus sequence comparisons

    Directory of Open Access Journals (Sweden)

    Nathan D. Olson

    2015-03-01

    Full Text Available This study presents the results from an interlaboratory sequencing study for which we developed a novel high-resolution method for comparing data from different sequencing platforms for a multi-copy, paralogous gene. The combination of PCR amplification and 16S ribosomal RNA gene (16S rRNA sequencing has revolutionized bacteriology by enabling rapid identification, frequently without the need for culture. To assess variability between laboratories in sequencing 16S rRNA, six laboratories sequenced the gene encoding the 16S rRNA from Escherichia coli O157:H7 strain EDL933 and Listeria monocytogenes serovar 4b strain NCTC11994. Participants performed sequencing methods and protocols available in their laboratories: Sanger sequencing, Roche 454 pyrosequencing®, or Ion Torrent PGM®. The sequencing data were evaluated on three levels: (1 identity of biologically conserved position, (2 ratio of 16S rRNA gene copies featuring identified variants, and (3 the collection of variant combinations in a set of 16S rRNA gene copies. The same set of biologically conserved positions was identified for each sequencing method. Analytical methods using Bayesian and maximum likelihood statistics were developed to estimate variant copy ratios, which describe the ratio of nucleotides at each identified biologically variable position, as well as the likely set of variant combinations present in 16S rRNA gene copies. Our results indicate that estimated variant copy ratios at biologically variable positions were only reproducible for high throughput sequencing methods. Furthermore, the likely variant combination set was only reproducible with increased sequencing depth and longer read lengths. We also demonstrate novel methods for evaluating variable positions when comparing multi-copy gene sequence data from multiple laboratories generated using multiple sequencing technologies.

  18. Short sequence motifs, overrepresented in mammalian conservednon-coding sequences

    Energy Technology Data Exchange (ETDEWEB)

    Minovitsky, Simon; Stegmaier, Philip; Kel, Alexander; Kondrashov,Alexey S.; Dubchak, Inna

    2007-02-21

    Background: A substantial fraction of non-coding DNAsequences of multicellular eukaryotes is under selective constraint. Inparticular, ~;5 percent of the human genome consists of conservednon-coding sequences (CNSs). CNSs differ from other genomic sequences intheir nucleotide composition and must play important functional roles,which mostly remain obscure.Results: We investigated relative abundancesof short sequence motifs in all human CNSs present in the human/mousewhole-genome alignments vs. three background sets of sequences: (i)weakly conserved or unconserved non-coding sequences (non-CNSs); (ii)near-promoter sequences (located between nucleotides -500 and -1500,relative to a start of transcription); and (iii) random sequences withthe same nucleotide composition as that of CNSs. When compared tonon-CNSs and near-promoter sequences, CNSs possess an excess of AT-richmotifs, often containing runs of identical nucleotides. In contrast, whencompared to random sequences, CNSs contain an excess of GC-rich motifswhich, however, lack CpG dinucleotides. Thus, abundance of short sequencemotifs in human CNSs, taken as a whole, is mostly determined by theiroverall compositional properties and not by overrepresentation of anyspecific short motifs. These properties are: (i) high AT-content of CNSs,(ii) a tendency, probably due to context-dependent mutation, of A's andT's to clump, (iii) presence of short GC-rich regions, and (iv) avoidanceof CpG contexts, due to their hypermutability. Only a small number ofshort motifs, overrepresented in all human CNSs are similar to bindingsites of transcription factors from the FOX family.Conclusion: Human CNSsas a whole appear to be too broad a class of sequences to possess strongfootprints of any short sequence-specific functions. Such footprintsshould be studied at the level of functional subclasses of CNSs, such asthose which flank genes with a particular pattern of expression. Overallproperties of CNSs are affected by

  19. Genomic sequencing in clinical trials

    OpenAIRE

    Mestan, Karen K; Ilkhanoff, Leonard; Mouli, Samdeep; Lin, Simon

    2011-01-01

    Abstract Human genome sequencing is the process by which the exact order of nucleic acid base pairs in the 24 human chromosomes is determined. Since the completion of the Human Genome Project in 2003, genomic sequencing is rapidly becoming a major part of our translational research efforts to understand and improve human health and disease. This article reviews the current and future directions of clinical research with respect to genomic sequencing, a technology that is just beginning to fin...

  20. Biosensors for DNA sequence detection

    Science.gov (United States)

    Vercoutere, Wenonah; Akeson, Mark

    2002-01-01

    DNA biosensors are being developed as alternatives to conventional DNA microarrays. These devices couple signal transduction directly to sequence recognition. Some of the most sensitive and functional technologies use fibre optics or electrochemical sensors in combination with DNA hybridization. In a shift from sequence recognition by hybridization, two emerging single-molecule techniques read sequence composition using zero-mode waveguides or electrical impedance in nanoscale pores.

  1. ABS: Sequence alignment by scanning

    KAUST Repository

    Bonny, Mohamed Talal

    2011-08-01

    Sequence alignment is an essential tool in almost any computational biology research. It processes large database sequences and considered to be high consumers of computation time. Heuristic algorithms are used to get approximate but fast results. We introduce fast alignment algorithm, called Alignment By Scanning (ABS), to provide an approximate alignment of two DNA sequences. We compare our algorithm with the well-known alignment algorithms, the FASTA (which is heuristic) and the \\'Needleman-Wunsch\\' (which is optimal). The proposed algorithm achieves up to 76% enhancement in alignment score when it is compared with the FASTA Algorithm. The evaluations are conducted using different lengths of DNA sequences. © 2011 IEEE.

  2. ABS: Sequence alignment by scanning

    KAUST Repository

    Bonny, Mohamed Talal; Salama, Khaled N.

    2011-01-01

    Sequence alignment is an essential tool in almost any computational biology research. It processes large database sequences and considered to be high consumers of computation time. Heuristic algorithms are used to get approximate but fast results. We introduce fast alignment algorithm, called Alignment By Scanning (ABS), to provide an approximate alignment of two DNA sequences. We compare our algorithm with the well-known alignment algorithms, the FASTA (which is heuristic) and the 'Needleman-Wunsch' (which is optimal). The proposed algorithm achieves up to 76% enhancement in alignment score when it is compared with the FASTA Algorithm. The evaluations are conducted using different lengths of DNA sequences. © 2011 IEEE.

  3. Fast global sequence alignment technique

    KAUST Repository

    Bonny, Mohamed Talal

    2011-11-01

    Bioinformatics database is growing exponentially in size. Processing these large amount of data may take hours of time even if super computers are used. One of the most important processing tool in Bioinformatics is sequence alignment. We introduce fast alignment algorithm, called \\'Alignment By Scanning\\' (ABS), to provide an approximate alignment of two DNA sequences. We compare our algorithm with the wellknown sequence alignment algorithms, the \\'GAP\\' (which is heuristic) and the \\'Needleman-Wunsch\\' (which is optimal). The proposed algorithm achieves up to 51% enhancement in alignment score when it is compared with the GAP Algorithm. The evaluations are conducted using different lengths of DNA sequences. © 2011 IEEE.

  4. Winnowing DNA for rare sequences: highly specific sequence and methylation based enrichment.

    Directory of Open Access Journals (Sweden)

    Jason D Thompson

    Full Text Available Rare mutations in cell populations are known to be hallmarks of many diseases and cancers. Similarly, differential DNA methylation patterns arise in rare cell populations with diagnostic potential such as fetal cells circulating in maternal blood. Unfortunately, the frequency of alleles with diagnostic potential, relative to wild-type background sequence, is often well below the frequency of errors in currently available methods for sequence analysis, including very high throughput DNA sequencing. We demonstrate a DNA preparation and purification method that through non-linear electrophoretic separation in media containing oligonucleotide probes, achieves 10,000 fold enrichment of target DNA with single nucleotide specificity, and 100 fold enrichment of unmodified methylated DNA differing from the background by the methylation of a single cytosine residue.

  5. Winnowing DNA for rare sequences: highly specific sequence and methylation based enrichment.

    Science.gov (United States)

    Thompson, Jason D; Shibahara, Gosuke; Rajan, Sweta; Pel, Joel; Marziali, Andre

    2012-01-01

    Rare mutations in cell populations are known to be hallmarks of many diseases and cancers. Similarly, differential DNA methylation patterns arise in rare cell populations with diagnostic potential such as fetal cells circulating in maternal blood. Unfortunately, the frequency of alleles with diagnostic potential, relative to wild-type background sequence, is often well below the frequency of errors in currently available methods for sequence analysis, including very high throughput DNA sequencing. We demonstrate a DNA preparation and purification method that through non-linear electrophoretic separation in media containing oligonucleotide probes, achieves 10,000 fold enrichment of target DNA with single nucleotide specificity, and 100 fold enrichment of unmodified methylated DNA differing from the background by the methylation of a single cytosine residue.

  6. Multilocus Sequence Typing of Total-Genome-Sequenced Bacteria

    DEFF Research Database (Denmark)

    Larsen, Mette Voldby; Cosentino, Salvatore; Rasmussen, Simon

    2012-01-01

    Accurate strain identification is essential for anyone working with bacteria. For many species, multilocus sequence typing (MLST) is considered the "gold standard" of typing, but it is traditionally performed in an expensive and time-consuming manner. As the costs of whole-genome sequencing (WGS...

  7. Perchlorate Removal, Destruction, and Field Monitoring Demonstration

    National Research Council Canada - National Science Library

    Coppola, Edward N; Davis, Andrea

    2006-01-01

    The objectives of this demonstration were to evaluate and demonstrate a complete perchlorate ion exchange process for groundwater that included a unique, regenerable, perchlorate-selective ion exchange resin...

  8. HTI retrieval demonstration project execution plan

    International Nuclear Information System (INIS)

    Ellingson, D.R.

    1997-01-01

    This plan describes the process for demonstrating the retrieval of difficult Hanford tank waste forms utilizing commercial technologies and the private sector to conduct the operations. The demonstration is to be conducted in Tank 241-C-106

  9. Introduction to Methods Demonstrations for Authentication

    International Nuclear Information System (INIS)

    Kouzes, Richard T.; Hansen, Randy R.; Pitts, W. K.

    2002-01-01

    During the Trilateral Initiative Technical Workshop on Authentication and Certification, PNNL will demonstrate some authentication technologies. This paper briefly describes the motivation for these demonstrations and provide background on them

  10. Dog Y chromosomal DNA sequence: identification, sequencing and SNP discovery

    Directory of Open Access Journals (Sweden)

    Kirkness Ewen

    2006-10-01

    Full Text Available Abstract Background Population genetic studies of dogs have so far mainly been based on analysis of mitochondrial DNA, describing only the history of female dogs. To get a picture of the male history, as well as a second independent marker, there is a need for studies of biallelic Y-chromosome polymorphisms. However, there are no biallelic polymorphisms reported, and only 3200 bp of non-repetitive dog Y-chromosome sequence deposited in GenBank, necessitating the identification of dog Y chromosome sequence and the search for polymorphisms therein. The genome has been only partially sequenced for one male dog, disallowing mapping of the sequence into specific chromosomes. However, by comparing the male genome sequence to the complete female dog genome sequence, candidate Y-chromosome sequence may be identified by exclusion. Results The male dog genome sequence was analysed by Blast search against the human genome to identify sequences with a best match to the human Y chromosome and to the female dog genome to identify those absent in the female genome. Candidate sequences were then tested for male specificity by PCR of five male and five female dogs. 32 sequences from the male genome, with a total length of 24 kbp, were identified as male specific, based on a match to the human Y chromosome, absence in the female dog genome and male specific PCR results. 14437 bp were then sequenced for 10 male dogs originating from Europe, Southwest Asia, Siberia, East Asia, Africa and America. Nine haplotypes were found, which were defined by 14 substitutions. The genetic distance between the haplotypes indicates that they originate from at least five wolf haplotypes. There was no obvious trend in the geographic distribution of the haplotypes. Conclusion We have identified 24159 bp of dog Y-chromosome sequence to be used for population genetic studies. We sequenced 14437 bp in a worldwide collection of dogs, identifying 14 SNPs for future SNP analyses, and

  11. SVX Sequencer Board

    International Nuclear Information System (INIS)

    Utes, M.

    1997-01-01

    The SVX Sequencer boards are 9U by 280mm circuit boards that reside in slots 2 through 21 of each of eight Eurocard crates in the D0 Detector Platform. The basic purpose is to control the SVX chips for data acquisition and when a trigger occurs, to gather the SVX data and relay the data to the VRB boards in the Movable Counting House. Functions and features are as follows: (1) Initialization of eight SVX chip strings using the MIL-STD-1553 data bus; (2) Real time manipulation of the SVX control lines to effect data acquisition, digitization, and readout based on the NRZ/Clock signals from the Controller; (3) Conversion of 8-bit electrical SVX readout data to an optical signal operating at 1.062 Gbit/sec, sent to the VRB. Eight HDIs will be serviced per board; (4) Built-in logic analyzer which can record the most important control and data lines during a data acquisition cycle and put this recorded information onto the 1553 bus; (5) Identification header and end of data trailer tacked onto data stream; (6) 1553 register which can read the current values of the control and data lines; (7) 1553 register which can test the optical link; (8) 1553 registers for crossing pulse width, calibration pulse voltage, and calibration pipeline select; (9) 1553 register for reading the optical drivers status link; (10) 1553 register for power control of SVX chips and ignoring bad SVX strings; (11) Front panel displays and LEDs show the board status at a glance; (12) In-system programmable EPLDs are programmed via 1553 or Altera's 'Bitblaster'; (13) Automatic readout abort after 45us; (14) Supplies BUSY signal back to Trigger Framework; (15) Supports a heartbeat system to prevent excessive SVX current draw; and (16) Supports a SVX power trip feature if heartbeat failure occurs.

  12. Sequence Algebra, Sequence Decision Diagrams and Dynamic Fault Trees

    International Nuclear Information System (INIS)

    Rauzy, Antoine B.

    2011-01-01

    A large attention has been focused on the Dynamic Fault Trees in the past few years. By adding new gates to static (regular) Fault Trees, Dynamic Fault Trees aim to take into account dependencies among events. Merle et al. proposed recently an algebraic framework to give a formal interpretation to these gates. In this article, we extend Merle et al.'s work by adopting a slightly different perspective. We introduce Sequence Algebras that can be seen as Algebras of Basic Events, representing failures of non-repairable components. We show how to interpret Dynamic Fault Trees within this framework. Finally, we propose a new data structure to encode sets of sequences of Basic Events: Sequence Decision Diagrams. Sequence Decision Diagrams are very much inspired from Minato's Zero-Suppressed Binary Decision Diagrams. We show that all operations of Sequence Algebras can be performed on this data structure.

  13. Sequencing genes in silico using single nucleotide polymorphisms

    Directory of Open Access Journals (Sweden)

    Zhang Xinyi

    2012-01-01

    Full Text Available Abstract Background The advent of high throughput sequencing technology has enabled the 1000 Genomes Project Pilot 3 to generate complete sequence data for more than 906 genes and 8,140 exons representing 697 subjects. The 1000 Genomes database provides a critical opportunity for further interpreting disease associations with single nucleotide polymorphisms (SNPs discovered from genetic association studies. Currently, direct sequencing of candidate genes or regions on a large number of subjects remains both cost- and time-prohibitive. Results To accelerate the translation from discovery to functional studies, we propose an in silico gene sequencing method (ISS, which predicts phased sequences of intragenic regions, using SNPs. The key underlying idea of our method is to infer diploid sequences (a pair of phased sequences/alleles at every functional locus utilizing the deep sequencing data from the 1000 Genomes Project and SNP data from the HapMap Project, and to build prediction models using flanking SNPs. Using this method, we have developed a database of prediction models for 611 known genes. Sequence prediction accuracy for these genes is 96.26% on average (ranges 79%-100%. This database of prediction models can be enhanced and scaled up to include new genes as the 1000 Genomes Project sequences additional genes on additional individuals. Applying our predictive model for the KCNJ11 gene to the Wellcome Trust Case Control Consortium (WTCCC Type 2 diabetes cohort, we demonstrate how the prediction of phased sequences inferred from GWAS SNP genotype data can be used to facilitate interpretation and identify a probable functional mechanism such as protein changes. Conclusions Prior to the general availability of routine sequencing of all subjects, the ISS method proposed here provides a time- and cost-effective approach to broadening the characterization of disease associated SNPs and regions, and facilitating the prioritization of candidate

  14. Sequencing of the Hepatitis C Virus: A Systematic Review.

    Directory of Open Access Journals (Sweden)

    Brendan Jacka

    Full Text Available Since the identification of hepatitis C virus (HCV, viral sequencing has been important in understanding HCV classification, epidemiology, evolution, transmission clustering, treatment response and natural history. The length and diversity of the HCV genome has resulted in analysis of certain regions of the virus, however there has been little standardisation of protocols. This systematic review was undertaken to map the location and frequency of sequencing on the HCV genome in peer reviewed publications, with the aim to produce a database of sequencing primers and amplicons to inform future research. Medline and Scopus databases were searched for English language publications based on keyword/MeSH terms related to sequence analysis (9 terms or HCV (3 terms, plus "primer" as a general search term. Exclusion criteria included non-HCV research, review articles, duplicate records, and incomplete description of HCV sequencing methods. The PCR primer locations of accepted publications were noted, and purpose of sequencing was determined. A total of 450 studies were accepted from the 2099 identified, with 629 HCV sequencing amplicons identified and mapped on the HCV genome. The most commonly sequenced region was the HVR-1 region, often utilised for studies of natural history, clustering/transmission, evolution and treatment response. Studies related to genotyping/classification or epidemiology of HCV genotype generally targeted the 5'UTR, Core and NS5B regions, while treatment response/resistance was assessed mainly in the NS3-NS5B region with emphasis on the Interferon sensitivity determining region (ISDR region of NS5A. While the sequencing of HCV is generally constricted to certain regions of the HCV genome there is little consistency in the positioning of sequencing primers, with the exception of a few highly referenced manuscripts. This study demonstrates the heterogeneity of HCV sequencing, providing a comprehensive database of previously

  15. High-throughput sequence alignment using Graphics Processing Units

    Directory of Open Access Journals (Sweden)

    Trapnell Cole

    2007-12-01

    Full Text Available Abstract Background The recent availability of new, less expensive high-throughput DNA sequencing technologies has yielded a dramatic increase in the volume of sequence data that must be analyzed. These data are being generated for several purposes, including genotyping, genome resequencing, metagenomics, and de novo genome assembly projects. Sequence alignment programs such as MUMmer have proven essential for analysis of these data, but researchers will need ever faster, high-throughput alignment tools running on inexpensive hardware to keep up with new sequence technologies. Results This paper describes MUMmerGPU, an open-source high-throughput parallel pairwise local sequence alignment program that runs on commodity Graphics Processing Units (GPUs in common workstations. MUMmerGPU uses the new Compute Unified Device Architecture (CUDA from nVidia to align multiple query sequences against a single reference sequence stored as a suffix tree. By processing the queries in parallel on the highly parallel graphics card, MUMmerGPU achieves more than a 10-fold speedup over a serial CPU version of the sequence alignment kernel, and outperforms the exact alignment component of MUMmer on a high end CPU by 3.5-fold in total application time when aligning reads from recent sequencing projects using Solexa/Illumina, 454, and Sanger sequencing technologies. Conclusion MUMmerGPU is a low cost, ultra-fast sequence alignment program designed to handle the increasing volume of data produced by new, high-throughput sequencing technologies. MUMmerGPU demonstrates that even memory-intensive applications can run significantly faster on the relatively low-cost GPU than on the CPU.

  16. Using Daily Horoscopes To Demonstrate Expectancy Confirmation.

    Science.gov (United States)

    Munro, Geoffrey D.; Munro, James E.

    2000-01-01

    Describes a classroom demonstration that uses daily horoscopes to show the effect that expectation can have on judgment. Addresses the preparation, procedure, and results of the demonstration, and student evaluations. States that the demonstration appears to be effective for teaching students about expectancy confirmation. (CMK)

  17. 40 CFR 117.14 - Demonstration projects.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Demonstration projects. 117.14 Section... DETERMINATION OF REPORTABLE QUANTITIES FOR HAZARDOUS SUBSTANCES Applicability § 117.14 Demonstration projects... research or demonstration projects relating to the prevention, control, or abatement of hazardous substance...

  18. Cone penetrometer demonstration standard startup review checklist

    International Nuclear Information System (INIS)

    KRIEG, S.A.

    1998-01-01

    Startup readiness for the Cone Penetrometer Demonstration in AX Tank Farm will be verified through the application of a Standard Startup Review Checklist. This is a listing of those items essential to demonstrating readiness to start the Cone Penetrometer Demonstration in AX Tank Farm

  19. Digital PCR provides sensitive and absolute calibration for high throughput sequencing

    Directory of Open Access Journals (Sweden)

    Fan H Christina

    2009-03-01

    Full Text Available Abstract Background Next-generation DNA sequencing on the 454, Solexa, and SOLiD platforms requires absolute calibration of the number of molecules to be sequenced. This requirement has two unfavorable consequences. First, large amounts of sample-typically micrograms-are needed for library preparation, thereby limiting the scope of samples which can be sequenced. For many applications, including metagenomics and the sequencing of ancient, forensic, and clinical samples, the quantity of input DNA can be critically limiting. Second, each library requires a titration sequencing run, thereby increasing the cost and lowering the throughput of sequencing. Results We demonstrate the use of digital PCR to accurately quantify 454 and Solexa sequencing libraries, enabling the preparation of sequencing libraries from nanogram quantities of input material while eliminating costly and time-consuming titration runs of the sequencer. We successfully sequenced low-nanogram scale bacterial and mammalian DNA samples on the 454 FLX and Solexa DNA sequencing platforms. This study is the first to definitively demonstrate the successful sequencing of picogram quantities of input DNA on the 454 platform, reducing the sample requirement more than 1000-fold without pre-amplification and the associated bias and reduction in library depth. Conclusion The digital PCR assay allows absolute quantification of sequencing libraries, eliminates uncertainties associated with the construction and application of standard curves to PCR-based quantification, and with a coefficient of variation close to 10%, is sufficiently precise to enable direct sequencing without titration runs.

  20. Demonstrating Heisenberg-limited unambiguous phase estimation without adaptive measurements

    International Nuclear Information System (INIS)

    Higgins, B L; Wiseman, H M; Pryde, G J; Berry, D W; Bartlett, S D; Mitchell, M W

    2009-01-01

    We derive, and experimentally demonstrate, an interferometric scheme for unambiguous phase estimation with precision scaling at the Heisenberg limit that does not require adaptive measurements. That is, with no prior knowledge of the phase, we can obtain an estimate of the phase with a standard deviation that is only a small constant factor larger than the minimum physically allowed value. Our scheme resolves the phase ambiguity that exists when multiple passes through a phase shift, or NOON states, are used to obtain improved phase resolution. Like a recently introduced adaptive technique (Higgins et al 2007 Nature 450 393), our experiment uses multiple applications of the phase shift on single photons. By not requiring adaptive measurements, but rather using a predetermined measurement sequence, the present scheme is both conceptually simpler and significantly easier to implement. Additionally, we demonstrate a simplified adaptive scheme that also surpasses the standard quantum limit for single passes.

  1. Quantifying population genetic differentiation from next-generation sequencing data

    DEFF Research Database (Denmark)

    Fumagalli, Matteo; Garrett Vieira, Filipe Jorge; Korneliussen, Thorfinn Sand

    2013-01-01

    method for quantifying population genetic differentiation from next-generation sequencing data. In addition, we present a strategy to investigate population structure via Principal Components Analysis. Through extensive simulations, we compare the new method herein proposed to approaches based...... on genotype calling and demonstrate a marked improvement in estimation accuracy for a wide range of conditions. We apply the method to a large-scale genomic data set of domesticated and wild silkworms sequenced at low coverage. We find that we can infer the fine-scale genetic structure of the sampled......Over the last few years, new high-throughput DNA sequencing technologies have dramatically increased speed and reduced sequencing costs. However, the use of these sequencing technologies is often challenged by errors and biases associated with the bioinformatical methods used for analyzing the data...

  2. SeqLib: a C ++ API for rapid BAM manipulation, sequence alignment and sequence assembly.

    Science.gov (United States)

    Wala, Jeremiah; Beroukhim, Rameen

    2017-03-01

    We present SeqLib, a C ++ API and command line tool that provides a rapid and user-friendly interface to BAM/SAM/CRAM files, global sequence alignment operations and sequence assembly. Four C libraries perform core operations in SeqLib: HTSlib for BAM access, BWA-MEM and BLAT for sequence alignment and Fermi for error correction and sequence assembly. Benchmarking indicates that SeqLib has lower CPU and memory requirements than leading C ++ sequence analysis APIs. We demonstrate an example of how minimal SeqLib code can extract, error-correct and assemble reads from a CRAM file and then align with BWA-MEM. SeqLib also provides additional capabilities, including chromosome-aware interval queries and read plotting. Command line tools are available for performing integrated error correction, micro-assemblies and alignment. SeqLib is available on Linux and OSX for the C ++98 standard and later at github.com/walaj/SeqLib. SeqLib is released under the Apache2 license. Additional capabilities for BLAT alignment are available under the BLAT license. jwala@broadinstitue.org ; rameen@broadinstitute.org. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

  3. Capillary gel electrophoresis for rapid, high resolution DNA sequencing.

    OpenAIRE

    Swerdlow, H; Gesteland, R

    1990-01-01

    Capillary gel electrophoresis has been demonstrated for the separation and detection of DNA sequencing samples. Enzymatic dideoxy nucleotide chain termination was employed, using fluorescently tagged oligonucleotide primers and laser based on-column detection (limit of detection is 6,000 molecules per peak). Capillary gel separations were shown to be three times faster, with better resolution (2.4 x), and higher separation efficiency (5.4 x) than a conventional automated slab gel DNA sequenci...

  4. Chameleon sequences in neurodegenerative diseases

    International Nuclear Information System (INIS)

    Bahramali, Golnaz; Goliaei, Bahram; Minuchehr, Zarrin; Salari, Ali

    2016-01-01

    Chameleon sequences can adopt either alpha helix sheet or a coil conformation. Defining chameleon sequences in PDB (Protein Data Bank) may yield to an insight on defining peptides and proteins responsible in neurodegeneration. In this research, we benefitted from the large PDB and performed a sequence analysis on Chameleons, where we developed an algorithm to extract peptide segments with identical sequences, but different structures. In order to find new chameleon sequences, we extracted a set of 8315 non-redundant protein sequences from the PDB with an identity less than 25%. Our data was classified to “helix to strand (HE)”, “helix to coil (HC)” and “strand to coil (CE)” alterations. We also analyzed the occurrence of singlet and doublet amino acids and the solvent accessibility in the chameleon sequences; we then sorted out the proteins with the most number of chameleon sequences and named them Chameleon Flexible Proteins (CFPs) in our dataset. Our data revealed that Gly, Val, Ile, Tyr and Phe, are the major amino acids in Chameleons. We also found that there are proteins such as Insulin Degrading Enzyme IDE and GTP-binding nuclear protein Ran (RAN) with the most number of chameleons (640 and 405 respectively). These proteins have known roles in neurodegenerative diseases. Therefore it can be inferred that other CFP's can serve as key proteins in neurodegeneration, and a study on them can shed light on curing and preventing neurodegenerative diseases.

  5. Direct, rapid RNA sequence analysis

    International Nuclear Information System (INIS)

    Peattie, D.A.

    1987-01-01

    The original methods of RNA sequence analysis were based on enzymatic production and chromatographic separation of overlapping oligonucleotide fragments from within an RNA molecule followed by identification of the mononucleotides comprising the oligomer. Over the past decade the field of nucleic acid sequencing has changed dramatically, however, and RNA molecules now can be sequenced in a variety of more streamlined fashions. Most of the more recent advances in RNA sequencing have involved one-dimensional electrophoretic separation of 32 P-end-labeled oligoribonucleotides on polyacrylamide gels. In this chapter the author discusses two of these methods for determining the nucleotide sequences of RNA molecules rapidly: the chemical method and the enzymatic method. Both methods are direct and degradative, i.e., they rely on fragmatic and chemical approaches should be utilized. The single-strand-specific ribonucleases (A, T 1 , T 2 , and S 1 ) provide an efficient means to locate double-helical regions rapidly, and the chemical reactions provide a means to determine the RNA sequence within these regions. In addition, the chemical reactions allow one to assign interactions to specific atoms and to distinguish secondary interactions from tertiary ones. If the RNA molecule is small enough to be sequenced directly by the enzymatic or chemical method, the probing reactions can be done easily at the same time as sequencing reactions

  6. Chameleon sequences in neurodegenerative diseases.

    Science.gov (United States)

    Bahramali, Golnaz; Goliaei, Bahram; Minuchehr, Zarrin; Salari, Ali

    2016-03-25

    Chameleon sequences can adopt either alpha helix sheet or a coil conformation. Defining chameleon sequences in PDB (Protein Data Bank) may yield to an insight on defining peptides and proteins responsible in neurodegeneration. In this research, we benefitted from the large PDB and performed a sequence analysis on Chameleons, where we developed an algorithm to extract peptide segments with identical sequences, but different structures. In order to find new chameleon sequences, we extracted a set of 8315 non-redundant protein sequences from the PDB with an identity less than 25%. Our data was classified to "helix to strand (HE)", "helix to coil (HC)" and "strand to coil (CE)" alterations. We also analyzed the occurrence of singlet and doublet amino acids and the solvent accessibility in the chameleon sequences; we then sorted out the proteins with the most number of chameleon sequences and named them Chameleon Flexible Proteins (CFPs) in our dataset. Our data revealed that Gly, Val, Ile, Tyr and Phe, are the major amino acids in Chameleons. We also found that there are proteins such as Insulin Degrading Enzyme IDE and GTP-binding nuclear protein Ran (RAN) with the most number of chameleons (640 and 405 respectively). These proteins have known roles in neurodegenerative diseases. Therefore it can be inferred that other CFP's can serve as key proteins in neurodegeneration, and a study on them can shed light on curing and preventing neurodegenerative diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Farey sequences and resistor networks

    Indian Academy of Sciences (India)

    Green's function, while the perturbation of a network is investigated in [3]. ... In Theorem 1 below, we employ the Farey sequence to establish a strict .... We next show that the Farey sequence method is applicable for circuits with n or fewer.

  8. DNA Sequencing by Capillary Electrophoresis

    Science.gov (United States)

    Karger, Barry L.; Guttman, Andras

    2009-01-01

    Sequencing of human and other genomes has been at the center of interest in the biomedical field over the past several decades and is now leading toward an era of personalized medicine. During this time, DNA sequencing methods have evolved from the labor intensive slab gel electrophoresis, through automated multicapillary electrophoresis systems using fluorophore labeling with multispectral imaging, to the “next generation” technologies of cyclic array, hybridization based, nanopore and single molecule sequencing. Deciphering the genetic blueprint and follow-up confirmatory sequencing of Homo sapiens and other genomes was only possible by the advent of modern sequencing technologies that was a result of step by step advances with a contribution of academics, medical personnel and instrument companies. While next generation sequencing is moving ahead at break-neck speed, the multicapillary electrophoretic systems played an essential role in the sequencing of the Human Genome, the foundation of the field of genomics. In this prospective, we wish to overview the role of capillary electrophoresis in DNA sequencing based in part of several of our articles in this journal. PMID:19517496

  9. Graphene nanodevices for DNA sequencing

    NARCIS (Netherlands)

    Heerema, S.J.; Dekker, C.

    2016-01-01

    Fast, cheap, and reliable DNA sequencing could be one of the most disruptive innovations of this decade, as it will pave the way for personalized medicine. In pursuit of such technology, a variety of nanotechnology-based approaches have been explored and established, including sequencing with

  10. Chameleon sequences in neurodegenerative diseases

    Energy Technology Data Exchange (ETDEWEB)

    Bahramali, Golnaz [Institute of Biochemistry and Biophysics, University of Tehran, Tehran (Iran, Islamic Republic of); Goliaei, Bahram, E-mail: goliaei@ut.ac.ir [Institute of Biochemistry and Biophysics, University of Tehran, Tehran (Iran, Islamic Republic of); Minuchehr, Zarrin, E-mail: minuchehr@nigeb.ac.ir [Department of Systems Biotechnology, National Institute of Genetic Engineering and Biotechnology, (NIGEB), Tehran (Iran, Islamic Republic of); Salari, Ali [Department of Systems Biotechnology, National Institute of Genetic Engineering and Biotechnology, (NIGEB), Tehran (Iran, Islamic Republic of)

    2016-03-25

    Chameleon sequences can adopt either alpha helix sheet or a coil conformation. Defining chameleon sequences in PDB (Protein Data Bank) may yield to an insight on defining peptides and proteins responsible in neurodegeneration. In this research, we benefitted from the large PDB and performed a sequence analysis on Chameleons, where we developed an algorithm to extract peptide segments with identical sequences, but different structures. In order to find new chameleon sequences, we extracted a set of 8315 non-redundant protein sequences from the PDB with an identity less than 25%. Our data was classified to “helix to strand (HE)”, “helix to coil (HC)” and “strand to coil (CE)” alterations. We also analyzed the occurrence of singlet and doublet amino acids and the solvent accessibility in the chameleon sequences; we then sorted out the proteins with the most number of chameleon sequences and named them Chameleon Flexible Proteins (CFPs) in our dataset. Our data revealed that Gly, Val, Ile, Tyr and Phe, are the major amino acids in Chameleons. We also found that there are proteins such as Insulin Degrading Enzyme IDE and GTP-binding nuclear protein Ran (RAN) with the most number of chameleons (640 and 405 respectively). These proteins have known roles in neurodegenerative diseases. Therefore it can be inferred that other CFP's can serve as key proteins in neurodegeneration, and a study on them can shed light on curing and preventing neurodegenerative diseases.

  11. Commercial Art: Scope and Sequence.

    Science.gov (United States)

    Nashville - Davidson County Metropolitan Public Schools, TN.

    This scope and sequence guide, developed for a commercial art vocational education program, represents an initial step in the development of a systemwide articulated curriculum sequence for all vocational programs within the Metropolitan Nashville Public School System. It was developed as a result of needs expressed by teachers, parents, and the…

  12. Rapid Diagnostics of Onboard Sequences

    Science.gov (United States)

    Starbird, Thomas W.; Morris, John R.; Shams, Khawaja S.; Maimone, Mark W.

    2012-01-01

    Keeping track of sequences onboard a spacecraft is challenging. When reviewing Event Verification Records (EVRs) of sequence executions on the Mars Exploration Rover (MER), operators often found themselves wondering which version of a named sequence the EVR corresponded to. The lack of this information drastically impacts the operators diagnostic capabilities as well as their situational awareness with respect to the commands the spacecraft has executed, since the EVRs do not provide argument values or explanatory comments. Having this information immediately available can be instrumental in diagnosing critical events and can significantly enhance the overall safety of the spacecraft. This software provides auditing capability that can eliminate that uncertainty while diagnosing critical conditions. Furthermore, the Restful interface provides a simple way for sequencing tools to automatically retrieve binary compiled sequence SCMFs (Space Command Message Files) on demand. It also enables developers to change the underlying database, while maintaining the same interface to the existing applications. The logging capabilities are also beneficial to operators when they are trying to recall how they solved a similar problem many days ago: this software enables automatic recovery of SCMF and RML (Robot Markup Language) sequence files directly from the command EVRs, eliminating the need for people to find and validate the corresponding sequences. To address the lack of auditing capability for sequences onboard a spacecraft during earlier missions, extensive logging support was added on the Mars Science Laboratory (MSL) sequencing server. This server is responsible for generating all MSL binary SCMFs from RML input sequences. The sequencing server logs every SCMF it generates into a MySQL database, as well as the high-level RML file and dictionary name inputs used to create the SCMF. The SCMF is then indexed by a hash value that is automatically included in all command

  13. Accident sequence quantification with KIRAP

    International Nuclear Information System (INIS)

    Kim, Tae Un; Han, Sang Hoon; Kim, Kil You; Yang, Jun Eon; Jeong, Won Dae; Chang, Seung Cheol; Sung, Tae Yong; Kang, Dae Il; Park, Jin Hee; Lee, Yoon Hwan; Hwang, Mi Jeong.

    1997-01-01

    The tasks of probabilistic safety assessment(PSA) consists of the identification of initiating events, the construction of event tree for each initiating event, construction of fault trees for event tree logics, the analysis of reliability data and finally the accident sequence quantification. In the PSA, the accident sequence quantification is to calculate the core damage frequency, importance analysis and uncertainty analysis. Accident sequence quantification requires to understand the whole model of the PSA because it has to combine all event tree and fault tree models, and requires the excellent computer code because it takes long computation time. Advanced Research Group of Korea Atomic Energy Research Institute(KAERI) has developed PSA workstation KIRAP(Korea Integrated Reliability Analysis Code Package) for the PSA work. This report describes the procedures to perform accident sequence quantification, the method to use KIRAP's cut set generator, and method to perform the accident sequence quantification with KIRAP. (author). 6 refs

  14. Accident sequence quantification with KIRAP

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Un; Han, Sang Hoon; Kim, Kil You; Yang, Jun Eon; Jeong, Won Dae; Chang, Seung Cheol; Sung, Tae Yong; Kang, Dae Il; Park, Jin Hee; Lee, Yoon Hwan; Hwang, Mi Jeong

    1997-01-01

    The tasks of probabilistic safety assessment(PSA) consists of the identification of initiating events, the construction of event tree for each initiating event, construction of fault trees for event tree logics, the analysis of reliability data and finally the accident sequence quantification. In the PSA, the accident sequence quantification is to calculate the core damage frequency, importance analysis and uncertainty analysis. Accident sequence quantification requires to understand the whole model of the PSA because it has to combine all event tree and fault tree models, and requires the excellent computer code because it takes long computation time. Advanced Research Group of Korea Atomic Energy Research Institute(KAERI) has developed PSA workstation KIRAP(Korea Integrated Reliability Analysis Code Package) for the PSA work. This report describes the procedures to perform accident sequence quantification, the method to use KIRAP`s cut set generator, and method to perform the accident sequence quantification with KIRAP. (author). 6 refs.

  15. Repeated DNA sequences in fungi

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, S K

    1974-11-01

    Several fungal species, representatives of all broad groups like basidiomycetes, ascomycetes and phycomycetes, were examined for the nature of repeated DNA sequences by DNA:DNA reassociation studies using hydroxyapatite chromatography. All of the fungal species tested contained 10 to 20 percent repeated DNA sequences. There are approximately 100 to 110 copies of repeated DNA sequences of approximately 4 x 10/sup 7/ daltons piece size of each. Repeated DNA sequence homoduplexes showed on average 5/sup 0/C difference of T/sub e/50 (temperature at which 50 percent duplexes dissociate) values from the corresponding homoduplexes of unfractionated whole DNA. It is suggested that a part of repetitive sequences in fungi constitutes mitochondrial DNA and a part of it constitutes nuclear DNA. (auth)

  16. [Complete genome sequencing and sequence analysis of BCG Tice].

    Science.gov (United States)

    Wang, Zhiming; Pan, Yuanlong; Wu, Jun; Zhu, Baoli

    2012-10-04

    The objective of this study is to obtain the complete genome sequence of Bacillus Calmette-Guerin Tice (BCG Tice), in order to provide more information about the molecular biology of BCG Tice and design more reasonable vaccines to prevent tuberculosis. We assembled the data from high-throughput sequencing with SOAPdenovo software, with many contigs and scaffolds obtained. There are many sequence gaps and physical gaps remained as a result of regional low coverage and low quality. We designed primers at the end of contigs and performed PCR amplification in order to link these contigs and scaffolds. With various enzymes to perform PCR amplification, adjustment of PCR reaction conditions, and combined with clone construction to sequence, all the gaps were finished. We obtained the complete genome sequence of BCG Tice and submitted it to GenBank of National Center for Biotechnology Information (NCBI). The genome of BCG Tice is 4334064 base pairs in length, with GC content 65.65%. The problems and strategies during the finishing step of BCG Tice sequencing are illuminated here, with the hope of affording some experience to those who are involved in the finishing step of genome sequencing. The microarray data were verified by our results.

  17. How Next-Generation Sequencing Has Aided Our Understanding of the Sequence Composition and Origin of B Chromosomes

    Directory of Open Access Journals (Sweden)

    Alevtina Ruban

    2017-10-01

    Full Text Available Accessory, supernumerary, or—most simply—B chromosomes, are found in many eukaryotic karyotypes. These small chromosomes do not follow the usual pattern of segregation, but rather are transmitted in a higher than expected frequency. As increasingly being demonstrated by next-generation sequencing (NGS, their structure comprises fragments of standard (A chromosomes, although in some plant species, their sequence also includes contributions from organellar genomes. Transcriptomic analyses of various animal and plant species have revealed that, contrary to what used to be the common belief, some of the B chromosome DNA is protein-encoding. This review summarizes the progress in understanding B chromosome biology enabled by the application of next-generation sequencing technology and state-of-the-art bioinformatics. In particular, a contrast is drawn between a direct sequencing approach and a strategy based on a comparative genomics as alternative routes that can be taken towards the identification of B chromosome sequences.

  18. Universal sequence replication, reversible polymerization and early functional biopolymers: a model for the initiation of prebiotic sequence evolution.

    Directory of Open Access Journals (Sweden)

    Sara Imari Walker

    Full Text Available Many models for the origin of life have focused on understanding how evolution can drive the refinement of a preexisting enzyme, such as the evolution of efficient replicase activity. Here we present a model for what was, arguably, an even earlier stage of chemical evolution, when polymer sequence diversity was generated and sustained before, and during, the onset of functional selection. The model includes regular environmental cycles (e.g. hydration-dehydration cycles that drive polymers between times of replication and functional activity, which coincide with times of different monomer and polymer diffusivity. Template-directed replication of informational polymers, which takes place during the dehydration stage of each cycle, is considered to be sequence-independent. New sequences are generated by spontaneous polymer formation, and all sequences compete for a finite monomer resource that is recycled via reversible polymerization. Kinetic Monte Carlo simulations demonstrate that this proposed prebiotic scenario provides a robust mechanism for the exploration of sequence space. Introduction of a polymer sequence with monomer synthetase activity illustrates that functional sequences can become established in a preexisting pool of otherwise non-functional sequences. Functional selection does not dominate system dynamics and sequence diversity remains high, permitting the emergence and spread of more than one functional sequence. It is also observed that polymers spontaneously form clusters in simulations where polymers diffuse more slowly than monomers, a feature that is reminiscent of a previous proposal that the earliest stages of life could have been defined by the collective evolution of a system-wide cooperation of polymer aggregates. Overall, the results presented demonstrate the merits of considering plausible prebiotic polymer chemistries and environments that would have allowed for the rapid turnover of monomer resources and for

  19. BAMUD Features Demonstration by System View

    Directory of Open Access Journals (Sweden)

    D. Kocur

    2004-09-01

    Full Text Available Direct-sequence code-division multiple access (DS-CDMA is afrequently used wireless technology in DS-CDMA communications. Theconventional DS-CDMA detector follows a single-user detection strategyin which each user is detected separately without regard for the otherusers. The better strategy is multi-user detection (MUD, whereinformation about multiple users is used to improve detection of eachindividual user. This paper presents an adaptive multi-user detectorconverging (for any initialization to the minimum mean square error(MMSE detector without requiring training sequences. This blindmulti-user detector (BAMUD requires no more knowledge than does theconventional single-user detector. The structure of adaptive blinddetector is simulated by the system design tool SystemView. The aimfocus is to verify theoretical knowledge of BAMUD structure usinghardware-oriented PC-based model in SystemView.

  20. Evaluation of a pooled strategy for high-throughput sequencing of cosmid clones from metagenomic libraries.

    Science.gov (United States)

    Lam, Kathy N; Hall, Michael W; Engel, Katja; Vey, Gregory; Cheng, Jiujun; Neufeld, Josh D; Charles, Trevor C

    2014-01-01

    High-throughput sequencing methods have been instrumental in the growing field of metagenomics, with technological improvements enabling greater throughput at decreased costs. Nonetheless, the economy of high-throughput sequencing cannot be fully leveraged in the subdiscipline of functional metagenomics. In this area of research, environmental DNA is typically cloned to generate large-insert libraries from which individual clones are isolated, based on specific activities of interest. Sequence data are required for complete characterization of such clones, but the sequencing of a large set of clones requires individual barcode-based sample preparation; this can become costly, as the cost of clone barcoding scales linearly with the number of clones processed, and thus sequencing a large number of metagenomic clones often remains cost-prohibitive. We investigated a hybrid Sanger/Illumina pooled sequencing strategy that omits barcoding altogether, and we evaluated this strategy by comparing the pooled sequencing results to reference sequence data obtained from traditional barcode-based sequencing of the same set of clones. Using identity and coverage metrics in our evaluation, we show that pooled sequencing can generate high-quality sequence data, without producing problematic chimeras. Though caveats of a pooled strategy exist and further optimization of the method is required to improve recovery of complete clone sequences and to avoid circumstances that generate unrecoverable clone sequences, our results demonstrate that pooled sequencing represents an effective and low-cost alternative for sequencing large sets of metagenomic clones.