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Sample records for cis-regulatory module explorer

  1. CREME: Cis-Regulatory Module Explorer for the Human Genome

    Energy Technology Data Exchange (ETDEWEB)

    Loots, G G; Sharan, R; Ovcharenko, I; Ben-Hur, A

    2004-02-11

    The binding of transcription factors to specific regulatory sequence elements is a primary mechanism for controlling gene transcription. Eukaryotic genes are often regulated by several transcription factors, whose binding sites are tightly clustered and form cis-regulatory modules. In this paper we present a web-server, CREME, for identifying and visualizing cis-regulatory modules in the promoter regions of a given set of potentially co-regulated genes. CREME relies on a database of putative transcription factor binding sites that have been annotated across the human genome using a library of position weight matrices and evolutionary conservation with the mouse and rat genomes. A search algorithm is applied to this dataset to identify combinations of transcription factors whose binding sites tend to co-occur in close proximity in the promoter regions of the input gene set. The identified cis-regulatory modules are statistically scored and significant combinations are reported and graphically visualized. Our web-server is available at http://creme.dcode.org/.

  2. Computational methods for the detection of cis-regulatory modules.

    Science.gov (United States)

    Van Loo, Peter; Marynen, Peter

    2009-09-01

    Metazoan transcription regulation occurs through the concerted action of multiple transcription factors that bind co-operatively to cis-regulatory modules (CRMs). The annotation of these key regulators of transcription is lagging far behind the annotation of the transcriptome itself. Here, we give an overview of existing computational methods to detect these CRMs in metazoan genomes. We subdivide these methods into three classes: CRM scanners screen sequences for CRMs based on predefined models that often consist of multiple position weight matrices (PWMs). CRM builders construct models of similar CRMs controlling a set of co-regulated or co-expressed genes. CRM genome screeners screen sequences or complete genomes for CRMs as homotypic or heterotypic clusters of binding sites for any combination of transcription factors. We believe that CRM scanners are currently the most advanced methods, although their applicability is limited. Finally, we argue that CRM builders that make use of PWM libraries will benefit greatly from future advances and will prove to be most instrumental for the annotation of regulatory regions in metazoan genomes. PMID:19498042

  3. Twine: display and analysis of cis-regulatory modules

    OpenAIRE

    Pearson, Joseph C.; Crews, Stephen T.

    2013-01-01

    Summary: Many algorithms analyze enhancers for overrepresentation of known and novel motifs, with the goal of identifying binding sites for direct regulators of gene expression. Twine is a Java GUI with multiple graphical representations (‘Views’) of enhancer alignments that displays motifs, as IUPAC consensus sequences or position frequency matrices, in the context of phylogenetic conservation to facilitate cis-regulatory element discovery. Thresholds of phylogenetic conservation and motif s...

  4. Studying the functional conservation of cis-regulatory modules and their transcriptional output

    OpenAIRE

    Bailey Timothy L; Bauer Denis C

    2008-01-01

    Abstract Background Cis-regulatory modules (CRMs) are distinct, genomic regions surrounding the target gene that can independently activate the promoter to drive transcription. The activation of a CRM is controlled by the binding of a certain combination of transcription factors (TFs). It would be of great benefit if the transcriptional output mediated by a specific CRM could be predicted. Of equal benefit would be identifying in silico a specific CRM as the driver of the expression in a spec...

  5. Evolutionarily Assembled cis-Regulatory Module at a Human Ciliopathy Locus

    Science.gov (United States)

    Lee, Jeong Ho; Silhavy, Jennifer L.; Lee, Ji Eun; Al-Gazali, Lihadh; Thomas, Sophie; Davis, Erica E.; Bielas, Stephanie L.; Hill, Kiley J.; Iannicelli, Miriam; Brancati, Francesco; Gabriel, Stacey B.; Russ, Carsten; Logan, Clare V.; Sharif, Saghira Malik; Bennett, Christopher P.; Abe, Masumi; Hildebrandt, Friedhelm; Diplas, Bill H.; Attié-Bitach, Tania; Katsanis, Nicholas; Rajab, Anna; Koul, Roshan; Sztriha, Laszlo; Waters, Elizabeth R.; Ferro-Novick, Susan; Woods, C. Geoffrey; Johnson, Colin A.; Valente, Enza Maria; Zaki, Maha S.; Gleeson, Joseph G.

    2013-01-01

    Neighboring genes are often coordinately expressed within cis-regulatory modules, but evidence that nonparalogous genes share functions in mammals is lacking. Here, we report that mutation of either TMEM138 or TMEM216 causes a phenotypically indistinguishable human ciliopathy, Joubert syndrome. Despite a lack of sequence homology, the genes are aligned in a head-to-tail configuration and joined by chromosomal rearrangement at the amphibian-to-reptile evolutionary transition. Expression of the two genes is mediated by a conserved regulatory element in the noncoding intergenic region. Coordinated expression is important for their interdependent cellular role in vesicular transport to primary cilia. Hence, during vertebrate evolution of genes involved in ciliogenesis, nonparalogous genes were arranged to a functional gene cluster with shared regulatory elements. PMID:22282472

  6. Validation of skeletal muscle cis-regulatory module predictions reveals nucleotide composition bias in functional enhancers.

    Directory of Open Access Journals (Sweden)

    Andrew T Kwon

    2011-12-01

    Full Text Available We performed a genome-wide scan for muscle-specific cis-regulatory modules (CRMs using three computational prediction programs. Based on the predictions, 339 candidate CRMs were tested in cell culture with NIH3T3 fibroblasts and C2C12 myoblasts for capacity to direct selective reporter gene expression to differentiated C2C12 myotubes. A subset of 19 CRMs validated as functional in the assay. The rate of predictive success reveals striking limitations of computational regulatory sequence analysis methods for CRM discovery. Motif-based methods performed no better than predictions based only on sequence conservation. Analysis of the properties of the functional sequences relative to inactive sequences identifies nucleotide sequence composition can be an important characteristic to incorporate in future methods for improved predictive specificity. Muscle-related TFBSs predicted within the functional sequences display greater sequence conservation than non-TFBS flanking regions. Comparison with recent MyoD and histone modification ChIP-Seq data supports the validity of the functional regions.

  7. Studying the functional conservation of cis-regulatory modules and their transcriptional output

    Directory of Open Access Journals (Sweden)

    Bailey Timothy L

    2008-04-01

    Full Text Available Abstract Background Cis-regulatory modules (CRMs are distinct, genomic regions surrounding the target gene that can independently activate the promoter to drive transcription. The activation of a CRM is controlled by the binding of a certain combination of transcription factors (TFs. It would be of great benefit if the transcriptional output mediated by a specific CRM could be predicted. Of equal benefit would be identifying in silico a specific CRM as the driver of the expression in a specific tissue or situation. We extend a recently developed biochemical modeling approach to manage both prediction tasks. Given a set of TFs, their protein concentrations, and the positions and binding strengths of each of the TFs in a putative CRM, the model predicts the transcriptional output of the gene. Our approach predicts the location of the regulating CRM by using predicted TF binding sites in regions near the gene as input to the model and searching for the region that yields a predicted transcription rate most closely matching the known rate. Results Here we show the ability of the model on the example of one of the CRMs regulating the eve gene, MSE2. A model trained on the MSE2 in D. melanogaster was applied to the surrounding sequence of the eve gene in seven other Drosophila species. The model successfully predicts the correct MSE2 location and output in six out of eight Drosophila species we examine. Conclusion The model is able to generalize from D. melanogaster to other Drosophila species and accurately predicts the location and transcriptional output of MSE2 in those species. However, we also show that the current model is not specific enough to function as a genome-wide CRM scanner, because it incorrectly predicts other genomic regions to be MSE2s.

  8. Computational and molecular dissection of an X-box cis-Regulatory module

    OpenAIRE

    Warrington, Timothy Burton

    2015-01-01

    Ciliopathies are a class of human diseases marked by dysfunction of the cellular organelle, cilia. While many of the molecular components that make up cilia have been identified and studied, comparatively little is understood about the transcriptional regulation of genes encoding these components. The conserved transcription factor Regulatory Factor X (RFX)/DAF-19, which acts through binding to the cis-regulatory motif known as X-box, has been shown to regulate ciliary genes in many animals f...

  9. ModuleMiner - improved computational detection of cis-regulatory modules: are there different modes of gene regulation in embryonic development and adult tissues?

    OpenAIRE

    Van Loo, Peter; Aerts, Stein; Thienpont, Bernard; De Moor, Bart; Moreau, Yves; Marynen, Peter

    2008-01-01

    We present ModuleMiner, a novel algorithm for computationally detecting cis-regulatory modules (CRMs) in a set of co-expressed genes. ModuleMiner outperforms other methods for CRM detection on benchmark data, and successfully detects CRMs in tissue-specific microarray clusters and in embryonic development gene sets. Interestingly, CRM predictions for differentiated tissues exhibit strong enrichment close to the transcription start site, whereas CRM predictions for embryonic development gene s...

  10. CisMiner: genome-wide in-silico cis-regulatory module prediction by fuzzy itemset mining.

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    Carmen Navarro

    Full Text Available Eukaryotic gene control regions are known to be spread throughout non-coding DNA sequences which may appear distant from the gene promoter. Transcription factors are proteins that coordinately bind to these regions at transcription factor binding sites to regulate gene expression. Several tools allow to detect significant co-occurrences of closely located binding sites (cis-regulatory modules, CRMs. However, these tools present at least one of the following limitations: 1 scope limited to promoter or conserved regions of the genome; 2 do not allow to identify combinations involving more than two motifs; 3 require prior information about target motifs. In this work we present CisMiner, a novel methodology to detect putative CRMs by means of a fuzzy itemset mining approach able to operate at genome-wide scale. CisMiner allows to perform a blind search of CRMs without any prior information about target CRMs nor limitation in the number of motifs. CisMiner tackles the combinatorial complexity of genome-wide cis-regulatory module extraction using a natural representation of motif combinations as itemsets and applying the Top-Down Fuzzy Frequent- Pattern Tree algorithm to identify significant itemsets. Fuzzy technology allows CisMiner to better handle the imprecision and noise inherent to regulatory processes. Results obtained for a set of well-known binding sites in the S. cerevisiae genome show that our method yields highly reliable predictions. Furthermore, CisMiner was also applied to putative in-silico predicted transcription factor binding sites to identify significant combinations in S. cerevisiae and D. melanogaster, proving that our approach can be further applied genome-wide to more complex genomes. CisMiner is freely accesible at: http://genome2.ugr.es/cisminer. CisMiner can be queried for the results presented in this work and can also perform a customized cis-regulatory module prediction on a query set of transcription factor binding

  11. Conserved cis-regulatory modules in promoters of genes encoding wheat high-molecular-weight glutenin subunits

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    Catherine eRAVEL

    2014-11-01

    Full Text Available The concentration and composition of the gliadin and glutenin seed storage proteins (SSPs in wheat flour are the most important determinants of its end-use value. In cereals, the synthesis of SSPs is predominantly regulated at the transcriptional level by a complex network involving at least five cis-elements in gene promoters. The high-molecular-weight glutenin subunits (HMW-GS are encoded by two tightly linked genes located on the long arms of group 1 chromosomes. Here, we sequenced and annotated the HMW-GS gene promoters of 22 electrophoretic wheat alleles to identify putative cis-regulatory motifs. We focused on 24 motifs known to be involved in SSP gene regulation. Most of them were identified in at least one HMW-GS gene promoter sequence. A common regulatory framework was observed in all the HMW-GS gene promoters, as they shared conserved cis-regulatory modules including all the five motifs known to regulate the transcription of SSP genes. This common regulatory framework comprises a composite box made of the GATA motifs and GCN4-like Motifs (GLMs and was shown to be functional as the GLMs are able to bind a bZIP transcriptional factor SPA (Storage Protein Activator. In addition to this regulatory framework, each HMW-GS gene promoter had additional motifs organized differently. The promoters of most highly expressed x-type HMW-GS genes contain an additional box predicted to bind R2R3-MYB transcriptional factors. However, the differences in annotation between promoter alleles could not be related to their level of expression. In summary, we identified a common modular organization of HMW-GS gene promoters but the lack of correlation between the cis-motifs of each HMW-GS gene promoter and their level of expression suggests that other cis-elements or other mechanisms regulate HMW-GS gene expression.

  12. Does positive selection drive transcription factor binding site turnover? A test with Drosophila cis-regulatory modules.

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    Bin Z He

    2011-04-01

    Full Text Available Transcription factor binding site(s (TFBS gain and loss (i.e., turnover is a well-documented feature of cis-regulatory module (CRM evolution, yet little attention has been paid to the evolutionary force(s driving this turnover process. The predominant view, motivated by its widespread occurrence, emphasizes the importance of compensatory mutation and genetic drift. Positive selection, in contrast, although it has been invoked in specific instances of adaptive gene expression evolution, has not been considered as a general alternative to neutral compensatory evolution. In this study we evaluate the two hypotheses by analyzing patterns of single nucleotide polymorphism in the TFBS of well-characterized CRM in two closely related Drosophila species, Drosophila melanogaster and Drosophila simulans. An important feature of the analysis is classification of TFBS mutations according to the direction of their predicted effect on binding affinity, which allows gains and losses to be evaluated independently along the two phylogenetic lineages. The observed patterns of polymorphism and divergence are not compatible with neutral evolution for either class of mutations. Instead, multiple lines of evidence are consistent with contributions of positive selection to TFBS gain and loss as well as purifying selection in its maintenance. In discussion, we propose a model to reconcile the finding of selection driving TFBS turnover with constrained CRM function over long evolutionary time.

  13. Finding cis-regulatory modules in Drosophila using phylogenetic hidden Markov models

    DEFF Research Database (Denmark)

    Wong, Wendy S W; Nielsen, Rasmus

    2007-01-01

    MOTIVATION: Finding the regulatory modules for transcription factors binding is an important step in elucidating the complex molecular mechanisms underlying regulation of gene expression. There are numerous methods available for solving this problem, however, very few of them take advantage of th...

  14. Network discovery pipeline elucidates conserved time-of-day-specific cis-regulatory modules.

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    Todd P Michael

    2008-02-01

    Full Text Available Correct daily phasing of transcription confers an adaptive advantage to almost all organisms, including higher plants. In this study, we describe a hypothesis-driven network discovery pipeline that identifies biologically relevant patterns in genome-scale data. To demonstrate its utility, we analyzed a comprehensive matrix of time courses interrogating the nuclear transcriptome of Arabidopsis thaliana plants grown under different thermocycles, photocycles, and circadian conditions. We show that 89% of Arabidopsis transcripts cycle in at least one condition and that most genes have peak expression at a particular time of day, which shifts depending on the environment. Thermocycles alone can drive at least half of all transcripts critical for synchronizing internal processes such as cell cycle and protein synthesis. We identified at least three distinct transcription modules controlling phase-specific expression, including a new midnight specific module, PBX/TBX/SBX. We validated the network discovery pipeline, as well as the midnight specific module, by demonstrating that the PBX element was sufficient to drive diurnal and circadian condition-dependent expression. Moreover, we show that the three transcription modules are conserved across Arabidopsis, poplar, and rice. These results confirm the complex interplay between thermocycles, photocycles, and the circadian clock on the daily transcription program, and provide a comprehensive view of the conserved genomic targets for a transcriptional network key to successful adaptation.

  15. A Hox Transcription Factor Collective Binds a Highly Conserved Distal-less cis-Regulatory Module to Generate Robust Transcriptional Outcomes.

    Science.gov (United States)

    Uhl, Juli D; Zandvakili, Arya; Gebelein, Brian

    2016-04-01

    cis-regulatory modules (CRMs) generate precise expression patterns by integrating numerous transcription factors (TFs). Surprisingly, CRMs that control essential gene patterns can differ greatly in conservation, suggesting distinct constraints on TF binding sites. Here, we show that a highly conserved Distal-less regulatory element (DCRE) that controls gene expression in leg precursor cells recruits multiple Hox, Extradenticle (Exd) and Homothorax (Hth) complexes to mediate dual outputs: thoracic activation and abdominal repression. Using reporter assays, we found that abdominal repression is particularly robust, as neither individual binding site mutations nor a DNA binding deficient Hth protein abolished cooperative DNA binding and in vivo repression. Moreover, a re-engineered DCRE containing a distinct configuration of Hox, Exd, and Hth sites also mediated abdominal Hox repression. However, the re-engineered DCRE failed to perform additional segment-specific functions such as thoracic activation. These findings are consistent with two emerging concepts in gene regulation: First, the abdominal Hox/Exd/Hth factors utilize protein-protein and protein-DNA interactions to form repression complexes on flexible combinations of sites, consistent with the TF collective model of CRM organization. Second, the conserved DCRE mediates multiple cell-type specific outputs, consistent with recent findings that pleiotropic CRMs are associated with conserved TF binding and added evolutionary constraints. PMID:27058369

  16. Combinatorial regulation modules on GmSBP2 promoter: a distal cis-regulatory domain confines the SBP2 promoter activity to the vascular tissue in vegetative organs.

    Science.gov (United States)

    Waclawovsky, Alessandro J; Freitas, Rejane L; Rocha, Carolina S; Contim, Luis Antônio S; Fontes, Elizabeth P B

    2006-01-01

    The Glycine max sucrose binding protein (GmSBP2) promoter directs phloem-specific expression of reporter genes in transgenic tobacco. Here, we identified cis-regulatory domains (CRD) that contribute with positive and negative regulation for the tissue-specific pattern of the GmSPB2 promoter. Negative regulatory elements in the distal CRD-A (-2000 to -700) sequences suppressed expression from the GmSBP2 promoter in tissues other than seed tissues and vascular tissues of vegetative organs. Deletion of this region relieved repression resulting in a constitutive promoter highly active in all tissues analyzed. Further deletions from the strong constitutive -700GmSBP2 promoter delimited several intercalating enhancer-like and repressing domains that function in a context-dependent manner. Histochemical examination revealed that the CRD-C (-445 to -367) harbors both negative and positive elements. This region abolished promoter expression in roots and in all tissues of stems except for the inner phloem. In contrast, it restores root meristem expression when fused to the -132pSBP2-GUS construct, which contains root meristem expression-repressing determinants mapped to the 44-bp CRD-G (-136 to -92). Thus, the GmSBP2 promoter is functionally organized into a proximal region with the combinatorial modular configuration of plant promoters and a distal domain, which restricts gene expression to the vascular tissues in vegetative organs. PMID:16574256

  17. Abundant raw material for cis-regulatory evolution in humans

    Science.gov (United States)

    Rockman, Matthew V.; Wray, Gregory A.

    2002-01-01

    Changes in gene expression and regulation--due in particular to the evolution of cis-regulatory DNA sequences--may underlie many evolutionary changes in phenotypes, yet little is known about the distribution of such variation in populations. We present in this study the first survey of experimentally validated functional cis-regulatory polymorphism. These data are derived from more than 140 polymorphisms involved in the regulation of 107 genes in Homo sapiens, the eukaryote species with the most available data. We find that functional cis-regulatory variation is widespread in the human genome and that the consequent variation in gene expression is twofold or greater for 63% of the genes surveyed. Transcription factor-DNA interactions are highly polymorphic, and regulatory interactions have been gained and lost within human populations. On average, humans are heterozygous at more functional cis-regulatory sites (>16,000) than at amino acid positions (human phenotypic variation.

  18. Using hexamers to predict cis-regulatory motifs in Drosophila

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    Kibler Dennis

    2005-10-01

    Full Text Available Abstract Background Cis-regulatory modules (CRMs are short stretches of DNA that help regulate gene expression in higher eukaryotes. They have been found up to 1 megabase away from the genes they regulate and can be located upstream, downstream, and even within their target genes. Due to the difficulty of finding CRMs using biological and computational techniques, even well-studied regulatory systems may contain CRMs that have not yet been discovered. Results We present a simple, efficient method (HexDiff based only on hexamer frequencies of known CRMs and non-CRM sequence to predict novel CRMs in regulatory systems. On a data set of 16 gap and pair-rule genes containing 52 known CRMs, predictions made by HexDiff had a higher correlation with the known CRMs than several existing CRM prediction algorithms: Ahab, Cluster Buster, MSCAN, MCAST, and LWF. After combining the results of the different algorithms, 10 putative CRMs were identified and are strong candidates for future study. The hexamers used by HexDiff to distinguish between CRMs and non-CRM sequence were also analyzed and were shown to be enriched in regulatory elements. Conclusion HexDiff provides an efficient and effective means for finding new CRMs based on known CRMs, rather than known binding sites.

  19. cis-Regulatory control of the initial neurogenic pattern of onecut gene expression in the sea urchin embryo.

    Science.gov (United States)

    Barsi, Julius C; Davidson, Eric H

    2016-01-01

    Specification of the ciliated band (CB) of echinoid embryos executes three spatial functions essential for postgastrular organization. These are establishment of a band about 5 cells wide which delimits and bounds other embryonic territories; definition of a neurogenic domain within this band; and generation within it of arrays of ciliary cells that bear the special long cilia from which the structure derives its name. In Strongylocentrotus purpuratus the spatial coordinates of the future ciliated band are initially and exactly determined by the disposition of a ring of cells that transcriptionally activate the onecut homeodomain regulatory gene, beginning in blastula stage, long before the appearance of the CB per se. Thus the cis-regulatory apparatus that governs onecut expression in the blastula directly reveals the genomic sequence code by which these aspects of the spatial organization of the embryo are initially determined. We screened the entire onecut locus and its flanking region for transcriptionally active cis-regulatory elements, and by means of BAC recombineered deletions identified three separated and required cis-regulatory modules that execute different functions. The operating logic of the crucial spatial control module accounting for the spectacularly precise and beautiful early onecut expression domain depends on spatial repression. Previously predicted oral ectoderm and aboral ectoderm repressors were identified by cis-regulatory mutation as the products of goosecoid and irxa genes respectively, while the pan-ectodermal activator SoxB1 supplies a transcriptional driver function. PMID:26522848

  20. Parallel Evolution of Chordate Cis-Regulatory Code for Development

    OpenAIRE

    Doglio, Laura; Goode, Debbie K.; Maria C. Pelleri; Pauls, Stefan; Frabetti, Flavia; Shimeld, Sebastian M; Vavouri, Tanya; Elgar, Greg

    2013-01-01

    Urochordates are the closest relatives of vertebrates and at the larval stage, possess a characteristic bilateral chordate body plan. In vertebrates, the genes that orchestrate embryonic patterning are in part regulated by highly conserved non-coding elements (CNEs), yet these elements have not been identified in urochordate genomes. Consequently the evolution of the cis-regulatory code for urochordate development remains largely uncharacterised. Here, we use genome-wide comparisons between C...

  1. Discovering cis-regulatory RNAs in Shewanella genomes by Support Vector Machines.

    Science.gov (United States)

    Xu, Xing; Ji, Yongmei; Stormo, Gary D

    2009-04-01

    An increasing number of cis-regulatory RNA elements have been found to regulate gene expression post-transcriptionally in various biological processes in bacterial systems. Effective computational tools for large-scale identification of novel regulatory RNAs are strongly desired to facilitate our exploration of gene regulation mechanisms and regulatory networks. We present a new computational program named RSSVM (RNA Sampler+Support Vector Machine), which employs Support Vector Machines (SVMs) for efficient identification of functional RNA motifs from random RNA secondary structures. RSSVM uses a set of distinctive features to represent the common RNA secondary structure and structural alignment predicted by RNA Sampler, a tool for accurate common RNA secondary structure prediction, and is trained with functional RNAs from a variety of bacterial RNA motif/gene families covering a wide range of sequence identities. When tested on a large number of known and random RNA motifs, RSSVM shows a significantly higher sensitivity than other leading RNA identification programs while maintaining the same false positive rate. RSSVM performs particularly well on sets with low sequence identities. The combination of RNA Sampler and RSSVM provides a new, fast, and efficient pipeline for large-scale discovery of regulatory RNA motifs. We applied RSSVM to multiple Shewanella genomes and identified putative regulatory RNA motifs in the 5' untranslated regions (UTRs) in S. oneidensis, an important bacterial organism with extraordinary respiratory and metal reducing abilities and great potential for bioremediation and alternative energy generation. From 1002 sets of 5'-UTRs of orthologous operons, we identified 166 putative regulatory RNA motifs, including 17 of the 19 known RNA motifs from Rfam, an additional 21 RNA motifs that are supported by literature evidence, 72 RNA motifs overlapping predicted transcription terminators or attenuators, and other candidate regulatory RNA motifs

  2. Brachyury, Foxa2 and the cis-Regulatory Origins of the Notochord.

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    Diana S José-Edwards

    2015-12-01

    Full Text Available A main challenge of modern biology is to understand how specific constellations of genes are activated to differentiate cells and give rise to distinct tissues. This study focuses on elucidating how gene expression is initiated in the notochord, an axial structure that provides support and patterning signals to embryos of humans and all other chordates. Although numerous notochord genes have been identified, the regulatory DNAs that orchestrate development and propel evolution of this structure by eliciting notochord gene expression remain mostly uncharted, and the information on their configuration and recurrence is still quite fragmentary. Here we used the simple chordate Ciona for a systematic analysis of notochord cis-regulatory modules (CRMs, and investigated their composition, architectural constraints, predictive ability and evolutionary conservation. We found that most Ciona notochord CRMs relied upon variable combinations of binding sites for the transcription factors Brachyury and/or Foxa2, which can act either synergistically or independently from one another. Notably, one of these CRMs contains a Brachyury binding site juxtaposed to an (AC microsatellite, an unusual arrangement also found in Brachyury-bound regulatory regions in mouse. In contrast, different subsets of CRMs relied upon binding sites for transcription factors of widely diverse families. Surprisingly, we found that neither intra-genomic nor interspecific conservation of binding sites were reliably predictive hallmarks of notochord CRMs. We propose that rather than obeying a rigid sequence-based cis-regulatory code, most notochord CRMs are rather unique. Yet, this study uncovered essential elements recurrently used by divergent chordates as basic building blocks for notochord CRMs.

  3. Brachyury, Foxa2 and the cis-Regulatory Origins of the Notochord.

    Science.gov (United States)

    José-Edwards, Diana S; Oda-Ishii, Izumi; Kugler, Jamie E; Passamaneck, Yale J; Katikala, Lavanya; Nibu, Yutaka; Di Gregorio, Anna

    2015-12-01

    A main challenge of modern biology is to understand how specific constellations of genes are activated to differentiate cells and give rise to distinct tissues. This study focuses on elucidating how gene expression is initiated in the notochord, an axial structure that provides support and patterning signals to embryos of humans and all other chordates. Although numerous notochord genes have been identified, the regulatory DNAs that orchestrate development and propel evolution of this structure by eliciting notochord gene expression remain mostly uncharted, and the information on their configuration and recurrence is still quite fragmentary. Here we used the simple chordate Ciona for a systematic analysis of notochord cis-regulatory modules (CRMs), and investigated their composition, architectural constraints, predictive ability and evolutionary conservation. We found that most Ciona notochord CRMs relied upon variable combinations of binding sites for the transcription factors Brachyury and/or Foxa2, which can act either synergistically or independently from one another. Notably, one of these CRMs contains a Brachyury binding site juxtaposed to an (AC) microsatellite, an unusual arrangement also found in Brachyury-bound regulatory regions in mouse. In contrast, different subsets of CRMs relied upon binding sites for transcription factors of widely diverse families. Surprisingly, we found that neither intra-genomic nor interspecific conservation of binding sites were reliably predictive hallmarks of notochord CRMs. We propose that rather than obeying a rigid sequence-based cis-regulatory code, most notochord CRMs are rather unique. Yet, this study uncovered essential elements recurrently used by divergent chordates as basic building blocks for notochord CRMs. PMID:26684323

  4. Detailed map of a cis-regulatory input function

    Science.gov (United States)

    Setty, Y.; Mayo, A. E.; Surette, M. G.; Alon, U.

    2003-06-01

    Most genes are regulated by multiple transcription factors that bind specific sites in DNA regulatory regions. These cis-regulatory regions perform a computation: the rate of transcription is a function of the active concentrations of each of the input transcription factors. Here, we used accurate gene expression measurements from living cell cultures, bearing GFP reporters, to map in detail the input function of the classic lacZYA operon of Escherichia coli, as a function of about a hundred combinations of its two inducers, cAMP and isopropyl -D-thiogalactoside (IPTG). We found an unexpectedly intricate function with four plateau levels and four thresholds. This result compares well with a mathematical model of the binding of the regulatory proteins cAMP receptor protein (CRP) and LacI to the lac regulatory region. The model is also used to demonstrate that with few mutations, the same region could encode much purer AND-like or even OR-like functions. This possibility means that the wild-type region is selected to perform an elaborate computation in setting the transcription rate. The present approach can be generally used to map the input functions of other genes.

  5. Changes in Cis-regulatory Elements during Morphological Evolution

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    Yu-Lee Paul

    2012-10-01

    Full Text Available How have animals evolved new body designs (morphological evolution? This requires explanations both for simple morphological changes, such as differences in pigmentation and hair patterns between different Drosophila populations and species, and also for more complex changes, such as differences in the forelimbs of mice and bats, and the necks of amphibians and reptiles. The genetic changes and pathways involved in these evolutionary steps require identification. Many, though not all, of these events occur by changes in cis-regulatory (enhancer elements within developmental genes. Enhancers are modular, each affecting expression in only one or a few tissues. Therefore it is possible to add, remove or alter an enhancer without producing changes in multiple tissues, and thereby avoid widespread (pleiotropic deleterious effects. Ideally, for a given step in morphological evolution it is necessary to identify (i the change in phenotype, (ii the changes in gene expression, (iii the DNA region, enhancer or otherwise, affected, (iv the mutation involved, (v the nature of the transcription or other factors that bind to this site. In practice these data are incomplete for most of the published studies upon morphological evolution. Here, the investigations are categorized according to how far these analyses have proceeded.

  6. Deciphering cis-regulatory control in inflammatory cells.

    Science.gov (United States)

    Ghisletti, Serena; Natoli, Gioacchino

    2013-01-01

    In innate immune system cells, such as macrophages and dendritic cells, deployment of inducible gene expression programmes in response to microbes and danger signals requires highly precise regulatory mechanisms. The inflammatory response has to be tailored based on both the triggering stimulus and its dose, and it has to be unfolded in a kinetically complex manner that suits the different phases of the inflammatory process. Genomic characterization of regulatory elements in this context indicated that transcriptional regulators involved in macrophage specification act as pioneer transcription factors (TFs) that generate regions of open chromatin that enable the recruitment of TFs activated in response to external inputs. Therefore, competence for responses to a specific stimulus is programmed at an early stage of differentiation by factors involved in lineage commitment and maintenance of cell identity, which are responsible for the organization of a cell-type-specific cis-regulatory repertoire. The basic functional and organizational principles that regulate inflammatory gene expression in professional cells of the innate immune system provide general paradigms on the interplay between differentiation and environmental responses. PMID:23650641

  7. The search for cis-regulatory driver mutations in cancer genomes

    OpenAIRE

    Poulos, Rebecca C.; Sloane, Mathew A; Hesson, Luke B; Wong, Jason W. H.

    2015-01-01

    With the advent of high-throughput and relatively inexpensive whole-genome sequencing technology, the focus of cancer research has begun to shift toward analyses of somatic mutations in non-coding cis-regulatory elements of the cancer genome. Cis-regulatory elements play an important role in gene regulation, with mutations in these elements potentially resulting in changes to the expression of linked genes. The recent discoveries of recurrent TERT promoter mutations in melanoma, and recurrent...

  8. Cis-regulatory Evolution of Chalcone-Synthase Expression in the Genus Arabidopsis

    OpenAIRE

    de Meaux, J. (Juliette); Pop, A.(National Institute for Physics and Nuclear Engineering, Bucharest, Romania); Mitchell-Olds, T.

    2006-01-01

    The contribution of cis-regulation to adaptive evolutionary change is believed to be essential, yet little is known about the evolutionary rules that govern regulatory sequences. Here, we characterize the short-term evolutionary dynamics of a cis-regulatory region within and among two closely related species, A. lyrata and A. halleri, and compare our findings to A. thaliana. We focused on the cis-regulatory region of chalcone synthase (CHS), a key enzyme involved in the synthesis of plant sec...

  9. Mutagenesis of GATA motifs controlling the endoderm regulator elt-2 reveals distinct dominant and secondary cis-regulatory elements.

    Science.gov (United States)

    Du, Lawrence; Tracy, Sharon; Rifkin, Scott A

    2016-04-01

    Cis-regulatory elements (CREs) are crucial links in developmental gene regulatory networks, but in many cases, it can be difficult to discern whether similar CREs are functionally equivalent. We found that despite similar conservation and binding capability to upstream activators, different GATA cis-regulatory motifs within the promoter of the C. elegans endoderm regulator elt-2 play distinctive roles in activating and modulating gene expression throughout development. We fused wild-type and mutant versions of the elt-2 promoter to a gfp reporter and inserted these constructs as single copies into the C. elegans genome. We then counted early embryonic gfp transcripts using single-molecule RNA FISH (smFISH) and quantified gut GFP fluorescence. We determined that a single primary dominant GATA motif located 527bp upstream of the elt-2 start codon was necessary for both embryonic activation and later maintenance of transcription, while nearby secondary GATA motifs played largely subtle roles in modulating postembryonic levels of elt-2. Mutation of the primary activating site increased low-level spatiotemporally ectopic stochastic transcription, indicating that this site acts repressively in non-endoderm cells. Our results reveal that CREs with similar GATA factor binding affinities in close proximity can play very divergent context-dependent roles in regulating the expression of a developmentally critical gene in vivo. PMID:26896592

  10. Bacterial regulon modeling and prediction based on systematic cis regulatory motif analyses

    Science.gov (United States)

    Liu, Bingqiang; Zhou, Chuan; Li, Guojun; Zhang, Hanyuan; Zeng, Erliang; Liu, Qi; Ma, Qin

    2016-03-01

    Regulons are the basic units of the response system in a bacterial cell, and each consists of a set of transcriptionally co-regulated operons. Regulon elucidation is the basis for studying the bacterial global transcriptional regulation network. In this study, we designed a novel co-regulation score between a pair of operons based on accurate operon identification and cis regulatory motif analyses, which can capture their co-regulation relationship much better than other scores. Taking full advantage of this discovery, we developed a new computational framework and built a novel graph model for regulon prediction. This model integrates the motif comparison and clustering and makes the regulon prediction problem substantially more solvable and accurate. To evaluate our prediction, a regulon coverage score was designed based on the documented regulons and their overlap with our prediction; and a modified Fisher Exact test was implemented to measure how well our predictions match the co-expressed modules derived from E. coli microarray gene-expression datasets collected under 466 conditions. The results indicate that our program consistently performed better than others in terms of the prediction accuracy. This suggests that our algorithms substantially improve the state-of-the-art, leading to a computational capability to reliably predict regulons for any bacteria.

  11. The search for cis-regulatory driver mutations in cancer genomes.

    Science.gov (United States)

    Poulos, Rebecca C; Sloane, Mathew A; Hesson, Luke B; Wong, Jason W H

    2015-10-20

    With the advent of high-throughput and relatively inexpensive whole-genome sequencing technology, the focus of cancer research has begun to shift toward analyses of somatic mutations in non-coding cis-regulatory elements of the cancer genome. Cis-regulatory elements play an important role in gene regulation, with mutations in these elements potentially resulting in changes to the expression of linked genes. The recent discoveries of recurrent TERT promoter mutations in melanoma, and recurrent mutations that create a super-enhancer regulating TAL1 expression in T-cell acute lymphoblastic leukaemia (T-ALL), have sparked significant interest in the search for other somatic cis-regulatory mutations driving cancer development. In this review, we look more closely at the TERT promoter and TAL1 enhancer alterations and use these examples to ask whether other cis-regulatory mutations may play a role in cancer susceptibility. In doing so, we make observations from the data emerging from recent research in this field, and describe the experimental and analytical approaches which could be adopted in the hope of better uncovering the true functional significance of somatic cis-regulatory mutations in cancer. PMID:26356674

  12. Hunting for Cis-Regulatory Elements in Proteins.

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    Gibson, Toby J; Kumar, Manjeet

    2016-02-24

    A new bioinformatics tool predicts natively disordered protein control elements that function in cis, opening the door to more systematic studies of this biomedically important class of protein modules. PMID:27135160

  13. cis-Regulatory and Protein Evolution in Orthologous and Duplicate Genes

    OpenAIRE

    Castillo-Davis, Cristian I.; Hartl, Daniel L.; Achaz, Guillaume

    2004-01-01

    The relationship between protein and regulatory sequence evolution is a central question in molecular evolution. It is currently not known to what extent changes in gene expression are coupled with the evolution of protein coding sequences, or whether these changes differ among orthologs (species homologs) and paralogs (duplicate genes). Here, we develop a method to measure the extent of functionally relevant cis-regulatory sequence change in homologous genes, and validate it using microarray...

  14. Genome-wide de novo prediction of cis-regulatory binding sites in prokaryotes

    OpenAIRE

    Zhang, Shaoqiang; Xu, Minli; Li, Shan; Su, Zhengchang

    2009-01-01

    Although cis-regulatory binding sites (CRBSs) are at least as important as the coding sequences in a genome, our general understanding of them in most sequenced genomes is very limited due to the lack of efficient and accurate experimental and computational methods for their characterization, which has largely hindered our understanding of many important biological processes. In this article, we describe a novel algorithm for genome-wide de novo prediction of CRBSs with high accuracy. We desi...

  15. Bounded search for de novo identification of degenerate cis-regulatory elements

    Directory of Open Access Journals (Sweden)

    Khetani Radhika S

    2006-05-01

    Full Text Available Abstract Background The identification of statistically overrepresented sequences in the upstream regions of coregulated genes should theoretically permit the identification of potential cis-regulatory elements. However, in practice many cis-regulatory elements are highly degenerate, precluding the use of an exhaustive word-counting strategy for their identification. While numerous methods exist for inferring base distributions using a position weight matrix, recent studies suggest that the independence assumptions inherent in the model, as well as the inability to reach a global optimum, limit this approach. Results In this paper, we report PRISM, a degenerate motif finder that leverages the relationship between the statistical significance of a set of binding sites and that of the individual binding sites. PRISM first identifies overrepresented, non-degenerate consensus motifs, then iteratively relaxes each one into a high-scoring degenerate motif. This approach requires no tunable parameters, thereby lending itself to unbiased performance comparisons. We therefore compare PRISM's performance against nine popular motif finders on 28 well-characterized S. cerevisiae regulons. PRISM consistently outperforms all other programs. Finally, we use PRISM to predict the binding sites of uncharacterized regulons. Our results support a proposed mechanism of action for the yeast cell-cycle transcription factor Stb1, whose binding site has not been determined experimentally. Conclusion The relationship between statistical measures of the binding sites and the set as a whole leads to a simple means of identifying the diverse range of cis-regulatory elements to which a protein binds. This approach leverages the advantages of word-counting, in that position dependencies are implicitly accounted for and local optima are more easily avoided. While we sacrifice guaranteed optimality to prevent the exponential blowup of exhaustive search, we prove that the error

  16. Identification of a cis-regulatory element by transient analysis of co-ordinately regulated genes

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    Allan Andrew C

    2008-07-01

    Full Text Available Abstract Background Transcription factors (TFs co-ordinately regulate target genes that are dispersed throughout the genome. This co-ordinate regulation is achieved, in part, through the interaction of transcription factors with conserved cis-regulatory motifs that are in close proximity to the target genes. While much is known about the families of transcription factors that regulate gene expression in plants, there are few well characterised cis-regulatory motifs. In Arabidopsis, over-expression of the MYB transcription factor PAP1 (PRODUCTION OF ANTHOCYANIN PIGMENT 1 leads to transgenic plants with elevated anthocyanin levels due to the co-ordinated up-regulation of genes in the anthocyanin biosynthetic pathway. In addition to the anthocyanin biosynthetic genes, there are a number of un-associated genes that also change in expression level. This may be a direct or indirect consequence of the over-expression of PAP1. Results Oligo array analysis of PAP1 over-expression Arabidopsis plants identified genes co-ordinately up-regulated in response to the elevated expression of this transcription factor. Transient assays on the promoter regions of 33 of these up-regulated genes identified eight promoter fragments that were transactivated by PAP1. Bioinformatic analysis on these promoters revealed a common cis-regulatory motif that we showed is required for PAP1 dependent transactivation. Conclusion Co-ordinated gene regulation by individual transcription factors is a complex collection of both direct and indirect effects. Transient transactivation assays provide a rapid method to identify direct target genes from indirect target genes. Bioinformatic analysis of the promoters of these direct target genes is able to locate motifs that are common to this sub-set of promoters, which is impossible to identify with the larger set of direct and indirect target genes. While this type of analysis does not prove a direct interaction between protein and DNA

  17. Conservation of shh cis-regulatory architecture of the coelacanth is consistent with its ancestral phylogenetic position

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    Lang Michael

    2010-11-01

    Full Text Available Abstract Background The modern coelacanth (Latimeria is the extant taxon of a basal sarcopterygian lineage and sister group to tetrapods. Apart from certain apomorphic traits, its morphology is characterized by a high degree of retention of ancestral vertebrate structures and little morphological change. An insight into the molecular evolution that may explain the unchanged character of Latimeria morphology requires the analysis of the expression patterns of developmental regulator genes and their cis-regulatory modules (CRMs. Results We describe the comparative and functional analysis of the sonic hedgehog (shh genomic region of Latimeria menadoensis. Several putative enhancers in the Latimeria shh locus have been identified by comparisons to sarcopterygian and actinopterygian extant species. Specific sequence conservation with all known actinopterygian enhancer elements has been detected. However, these elements are selectively missing in more recently diverged actinopterygian and sarcopterygian species. The functionality of the putative Latimeria enhancers was confirmed by reporter gene expression analysis in transient transgenic zebrafish and chick embryos. Conclusions Latimeria shh CRMs represent the ancestral set of enhancers that have emerged before the split of lobe-finned and ray-finned fishes. In contrast to lineage-specific losses and differentiations in more derived lineages, Latimeria shh enhancers reveal low levels of sequence diversification. High overall sequence conservation of shh conserved noncoding elements (CNE is consistent with the general trend of high levels of conservation of noncoding DNA in the slowly evolving Latimeria genome.

  18. Plasticity of the cis-regulatory input function of a gene.

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    Avraham E Mayo

    2006-04-01

    Full Text Available The transcription rate of a gene is often controlled by several regulators that bind specific sites in the gene's cis-regulatory region. The combined effect of these regulators is described by a cis-regulatory input function. What determines the form of an input function, and how variable is it with respect to mutations? To address this, we employ the well-characterized lac operon of Escherichia coli, which has an elaborate input function, intermediate between Boolean AND-gate and OR-gate logic. We mapped in detail the input function of 12 variants of the lac promoter, each with different point mutations in the regulator binding sites, by means of accurate expression measurements from living cells. We find that even a few mutations can significantly change the input function, resulting in functions that resemble Pure AND gates, OR gates, or single-input switches. Other types of gates were not found. The variant input functions can be described in a unified manner by a mathematical model. The model also lets us predict which functions cannot be reached by point mutations. The input function that we studied thus appears to be plastic, in the sense that many of the mutations do not ruin the regulation completely but rather result in new ways to integrate the inputs.

  19. Transcription of Mammalian cis-Regulatory Elements Is Restrained by Actively Enforced Early Termination.

    Science.gov (United States)

    Austenaa, Liv M I; Barozzi, Iros; Simonatto, Marta; Masella, Silvia; Della Chiara, Giulia; Ghisletti, Serena; Curina, Alessia; de Wit, Elzo; Bouwman, Britta A M; de Pretis, Stefano; Piccolo, Viviana; Termanini, Alberto; Prosperini, Elena; Pelizzola, Mattia; de Laat, Wouter; Natoli, Gioacchino

    2015-11-01

    Upon recruitment to active enhancers and promoters, RNA polymerase II (Pol II) generates short non-coding transcripts of unclear function. The mechanisms that control the length and the amount of ncRNAs generated by cis-regulatory elements are largely unknown. Here, we show that the adaptor protein WDR82 and its associated complexes actively limit such non-coding transcription. WDR82 targets the SET1 H3K4 methyltransferases and the nuclear protein phosphatase 1 (PP1) complexes to the initiating Pol II. WDR82 and PP1 also interact with components of the transcriptional termination and RNA processing machineries. Depletion of WDR82, SET1, or the PP1 subunit required for its nuclear import caused distinct but overlapping transcription termination defects at highly expressed genes and active enhancers and promoters, thus enabling the increased synthesis of unusually long ncRNAs. These data indicate that transcription initiated from cis-regulatory elements is tightly coordinated with termination mechanisms that impose the synthesis of short RNAs. PMID:26593720

  20. Genome-wide de novo prediction of cis-regulatory binding sites in prokaryotes

    Science.gov (United States)

    Zhang, Shaoqiang; Xu, Minli; Su, Zhengchang

    2009-01-01

    Although cis-regulatory binding sites (CRBSs) are at least as important as the coding sequences in a genome, our general understanding of them in most sequenced genomes is very limited due to the lack of efficient and accurate experimental and computational methods for their characterization, which has largely hindered our understanding of many important biological processes. In this article, we describe a novel algorithm for genome-wide de novo prediction of CRBSs with high accuracy. We designed our algorithm to circumvent three identified difficulties for CRBS prediction using comparative genomics principles based on a new method for the selection of reference genomes, a new metric for measuring the similarity of CRBSs, and a new graph clustering procedure. When operon structures are correctly predicted, our algorithm can predict 81% of known individual binding sites belonging to 94% of known cis-regulatory motifs in the Escherichia coli K12 genome, while achieving high prediction specificity. Our algorithm has also achieved similar prediction accuracy in the Bacillus subtilis genome, suggesting that it is very robust, and thus can be applied to any other sequenced prokaryotic genome. When compared with the prior state-of-the-art algorithms, our algorithm outperforms them in both prediction sensitivity and specificity. PMID:19383880

  1. A primer on regression methods for decoding cis-regulatory logic

    Energy Technology Data Exchange (ETDEWEB)

    Das, Debopriya; Pellegrini, Matteo; Gray, Joe W.

    2009-03-03

    The rapidly emerging field of systems biology is helping us to understand the molecular determinants of phenotype on a genomic scale [1]. Cis-regulatory elements are major sequence-based determinants of biological processes in cells and tissues [2]. For instance, during transcriptional regulation, transcription factors (TFs) bind to very specific regions on the promoter DNA [2,3] and recruit the basal transcriptional machinery, which ultimately initiates mRNA transcription (Figure 1A). Learning cis-Regulatory Elements from Omics Data A vast amount of work over the past decade has shown that omics data can be used to learn cis-regulatory logic on a genome-wide scale [4-6]--in particular, by integrating sequence data with mRNA expression profiles. The most popular approach has been to identify over-represented motifs in promoters of genes that are coexpressed [4,7,8]. Though widely used, such an approach can be limiting for a variety of reasons. First, the combinatorial nature of gene regulation is difficult to explicitly model in this framework. Moreover, in many applications of this approach, expression data from multiple conditions are necessary to obtain reliable predictions. This can potentially limit the use of this method to only large data sets [9]. Although these methods can be adapted to analyze mRNA expression data from a pair of biological conditions, such comparisons are often confounded by the fact that primary and secondary response genes are clustered together--whereas only the primary response genes are expected to contain the functional motifs [10]. A set of approaches based on regression has been developed to overcome the above limitations [11-32]. These approaches have their foundations in certain biophysical aspects of gene regulation [26,33-35]. That is, the models are motivated by the expected transcriptional response of genes due to the binding of TFs to their promoters. While such methods have gathered popularity in the computational domain

  2. [Identification and mapping of cis-regulatory elements within long genomic sequences].

    Science.gov (United States)

    Akopov, S B; Chernov, I P; Vetchinova, A S; Bulanenkova, S S; Nikolaev, L G

    2007-01-01

    The publication of the human and other metazoan genome sequences opened up the possibility for mapping and analysis of genomic regulatory elements. Unfortunately, experimental data on genomic positions of such sequences as enhancers, silencers, insulators, transcription terminators, and replication origins are very limited, especially at the whole genome level. As most genomic regulatory elements (e.g., enhancers) are generally gene-, tissue-, or cell-specific, the prediction of these elements in silico is often ambiguous. Therefore, the development of high-throughput experimental approaches for identification and mapping of genomic functional elements is highly desirable. In this review we discuss novel approaches to high-throughput experimental identification of mammalian genomes cis-regulatory elements which is a necessary step toward the complete genome annotation. PMID:18240562

  3. Cis-regulatory architecture of a brain signaling center predates the origin of chordates.

    Science.gov (United States)

    Yao, Yao; Minor, Paul J; Zhao, Ying-Tao; Jeong, Yongsu; Pani, Ariel M; King, Anna N; Symmons, Orsolya; Gan, Lin; Cardoso, Wellington V; Spitz, François; Lowe, Christopher J; Epstein, Douglas J

    2016-05-01

    Genomic approaches have predicted hundreds of thousands of tissue-specific cis-regulatory sequences, but the determinants critical to their function and evolutionary history are mostly unknown. Here we systematically decode a set of brain enhancers active in the zona limitans intrathalamica (zli), a signaling center essential for vertebrate forebrain development via the secreted morphogen Sonic hedgehog (Shh). We apply a de novo motif analysis tool to identify six position-independent sequence motifs together with their cognate transcription factors that are essential for zli enhancer activity and Shh expression in the mouse embryo. Using knowledge of this regulatory lexicon, we discover new Shh zli enhancers in mice and a functionally equivalent element in hemichordates, indicating an ancient origin of the Shh zli regulatory network that predates the chordate phylum. These findings support a strategy for delineating functionally conserved enhancers in the absence of overt sequence homologies and over extensive evolutionary distances. PMID:27064252

  4. Lessons from Domestication: Targeting Cis-Regulatory Elements for Crop Improvement.

    Science.gov (United States)

    Swinnen, Gwen; Goossens, Alain; Pauwels, Laurens

    2016-06-01

    Domestication of wild plant species has provided us with crops that serve our human nutritional needs. Advanced DNA sequencing has propelled the unveiling of underlying genetic changes associated with domestication. Interestingly, many changes reside in cis-regulatory elements (CREs) that control the expression of an unmodified coding sequence. Sequence variation in CREs can impact gene expression levels, but also developmental timing and tissue specificity of expression. When genes are involved in multiple pathways or active in several organs and developmental stages CRE modifications are favored in contrast to mutations in coding regions, due to the lack of detrimental pleiotropic effects. Therefore, learning from domestication, we propose that CREs are interesting targets for genome editing to create new alleles for plant breeding. PMID:26876195

  5. Nutritional control of gene expression in Drosophila larvae via TOR, Myc and a novel cis-regulatory element

    Directory of Open Access Journals (Sweden)

    Grewal Savraj S

    2010-01-01

    Full Text Available Abstract Background Nutrient availability is a key determinant of eukaryotic cell growth. In unicellular organisms many signaling and transcriptional networks link nutrient availability to the expression of metabolic genes required for growth. However, less is known about the corresponding mechanisms that operate in metazoans. We used gene expression profiling to explore this issue in developing Drosophila larvae. Results We found that starvation for dietary amino acids (AA's leads to dynamic changes in transcript levels of many metabolic genes. The conserved insulin/PI3K and TOR signaling pathways mediate nutrition-dependent growth in Drosophila and other animals. We found that many AA starvation-responsive transcripts were also altered in TOR mutants. In contrast, although PI3K overexpression induced robust changes in the expression of many metabolic genes, these changes showed limited overlap with the AA starvation expression profile. We did however identify a strong overlap between genes regulated by the transcription factor, Myc, and AA starvation-responsive genes, particularly those involved in ribosome biogenesis, protein synthesis and mitochondrial function. The consensus Myc DNA binding site is enriched in promoters of these AA starvation genes, and we found that Myc overexpression could bypass dietary AA to induce expression of these genes. We also identified another sequence motif (Motif 1 enriched in the promoters of AA starvation-responsive genes. We showed that Motif 1 was both necessary and sufficient to mediate transcriptional responses to dietary AA in larvae. Conclusions Our data suggest that many of the transcriptional effects of amino acids are mediated via signaling through the TOR pathway in Drosophila larvae. We also find that these transcriptional effects are mediated through at least two mechanisms: via the transcription factor Myc, and via the Motif 1 cis-regulatory element. These studies begin to elucidate a nutrient

  6. Characterization of Putative cis-Regulatory Elements in Genes Preferentially Expressed in Arabidopsis Male Meiocytes

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    Junhua Li

    2014-01-01

    Full Text Available Meiosis is essential for plant reproduction because it is the process during which homologous chromosome pairing, synapsis, and meiotic recombination occur. The meiotic transcriptome is difficult to investigate because of the size of meiocytes and the confines of anther lobes. The recent development of isolation techniques has enabled the characterization of transcriptional profiles in male meiocytes of Arabidopsis. Gene expression in male meiocytes shows unique features. The direct interaction of transcription factors (TFs with DNA regulatory sequences forms the basis for the specificity of transcriptional regulation. Here, we identified putative cis-regulatory elements (CREs associated with male meiocyte-expressed genes using in silico tools. The upstream regions (1 kb of the top 50 genes preferentially expressed in Arabidopsis meiocytes possessed conserved motifs. These motifs are putative binding sites of TFs, some of which share common functions, such as roles in cell division. In combination with cell-type-specific analysis, our findings could be a substantial aid for the identification and experimental verification of the protein-DNA interactions for the specific TFs that drive gene expression in meiocytes.

  7. The Hematopoietic Stem and Progenitor Cell Cistrome: GATA Factor-Dependent cis-Regulatory Mechanisms.

    Science.gov (United States)

    Hewitt, K J; Johnson, K D; Gao, X; Keles, S; Bresnick, E H

    2016-01-01

    Transcriptional regulators mediate the genesis and function of the hematopoietic system by binding complex ensembles of cis-regulatory elements to establish genetic networks. While thousands to millions of any given cis-element resides in a genome, how transcriptional regulators select these sites and how site attributes dictate functional output is not well understood. An instructive system to address this problem involves the GATA family of transcription factors that control vital developmental and physiological processes and are linked to multiple human pathologies. Although GATA factors bind DNA motifs harboring the sequence GATA, only a very small subset of these abundant motifs are occupied in genomes. Mechanistic studies revealed a unique configuration of a GATA factor-regulated cis-element consisting of an E-box and a downstream GATA motif separated by a short DNA spacer. GATA-1- or GATA-2-containing multiprotein complexes at these composite elements control transcription of genes critical for hematopoietic stem cell emergence in the mammalian embryo, hematopoietic progenitor cell regulation, and erythroid cell maturation. Other constituents of the complex include the basic helix-loop-loop transcription factor Scl/TAL1, its heterodimeric partner E2A, and the Lim domain proteins LMO2 and LDB1. This chapter reviews the structure/function of E-box-GATA composite cis-elements, which collectively constitute an important sector of the hematopoietic stem and progenitor cell cistrome. PMID:27137654

  8. Mapping Association between Long-Range Cis-Regulatory Regions and Their Target Genes Using Comparative Genomics

    Science.gov (United States)

    Mongin, Emmanuel; Dewar, Ken; Blanchette, Mathieu

    In chordates, long-range cis-regulatory regions are involved in the control of transcription initiation (either as repressors or enhancers). They can be located as far as 1 Mb from the transcription start site of the target gene and can regulate more than one gene. Therefore, proper characterization of functional interactions between long-range cis-regulatory regions and their target genes remains problematic. We present a novel method to predict such interactions based on the analysis of rearrangements between the human and 16 other vertebrate genomes. Our method is based on the assumption that genome rearrangements that would disrupt the functional interaction between a cis-regulatory region and its target gene are likely to be deleterious. Therefore, conservation of synteny through evolution would be an indication of a functional interaction. We use our algorithm to classify a set of 1,406,084 putative associations from the human genome. This genome-wide map of interactions has many potential applications, including the selection of candidate regions prior to in vivo experimental characterization, a better characterization of regulatory regions involved in position effect diseases, and an improved understanding of the mechanisms and importance of long-range regulation.

  9. Changes in cis-regulatory elements of a key floral regulator are associated with divergence of inflorescence architectures.

    Science.gov (United States)

    Kusters, Elske; Della Pina, Serena; Castel, Rob; Souer, Erik; Koes, Ronald

    2015-08-15

    Higher plant species diverged extensively with regard to the moment (flowering time) and position (inflorescence architecture) at which flowers are formed. This seems largely caused by variation in the expression patterns of conserved genes that specify floral meristem identity (FMI), rather than changes in the encoded proteins. Here, we report a functional comparison of the promoters of homologous FMI genes from Arabidopsis, petunia, tomato and Antirrhinum. Analysis of promoter-reporter constructs in petunia and Arabidopsis, as well as complementation experiments, showed that the divergent expression of leafy (LFY) and the petunia homolog aberrant leaf and flower (ALF) results from alterations in the upstream regulatory network rather than cis-regulatory changes. The divergent expression of unusual floral organs (UFO) from Arabidopsis, and the petunia homolog double top (DOT), however, is caused by the loss or gain of cis-regulatory promoter elements, which respond to trans-acting factors that are expressed in similar patterns in both species. Introduction of pUFO:UFO causes no obvious defects in Arabidopsis, but in petunia it causes the precocious and ectopic formation of flowers. This provides an example of how a change in a cis-regulatory region can account for a change in the plant body plan. PMID:26220938

  10. Deciphering Cis-Regulatory Element Mediated Combinatorial Regulation in Rice under Blast Infected Condition.

    Science.gov (United States)

    Deb, Arindam; Kundu, Sudip

    2015-01-01

    Combinations of cis-regulatory elements (CREs) present at the promoters facilitate the binding of several transcription factors (TFs), thereby altering the consequent gene expressions. Due to the eminent complexity of the regulatory mechanism, the combinatorics of CRE-mediated transcriptional regulation has been elusive. In this work, we have developed a new methodology that quantifies the co-occurrence tendencies of CREs present in a set of promoter sequences; these co-occurrence scores are filtered in three consecutive steps to test their statistical significance; and the significantly co-occurring CRE pairs are presented as networks. These networks of co-occurring CREs are further transformed to derive higher order of regulatory combinatorics. We have further applied this methodology on the differentially up-regulated gene-sets of rice tissues under fungal (Magnaporthe) infected conditions to demonstrate how it helps to understand the CRE-mediated combinatorial gene regulation. Our analysis includes a wide spectrum of biologically important results. The CRE pairs having a strong tendency to co-occur often exhibit very similar joint distribution patterns at the promoters of rice. We couple the network approach with experimental results of plant gene regulation and defense mechanisms and find evidences of auto and cross regulation among TF families, cross-talk among multiple hormone signaling pathways, similarities and dissimilarities in regulatory combinatorics between different tissues, etc. Our analyses have pointed a highly distributed nature of the combinatorial gene regulation facilitating an efficient alteration in response to fungal attack. All together, our proposed methodology could be an important approach in understanding the combinatorial gene regulation. It can be further applied to unravel the tissue and/or condition specific combinatorial gene regulation in other eukaryotic systems with the availability of annotated genomic sequences and suitable

  11. Identification of High-Impact cis-Regulatory Mutations Using Transcription Factor Specific Random Forest Models.

    Science.gov (United States)

    Svetlichnyy, Dmitry; Imrichova, Hana; Fiers, Mark; Kalender Atak, Zeynep; Aerts, Stein

    2015-11-01

    Cancer genomes contain vast amounts of somatic mutations, many of which are passenger mutations not involved in oncogenesis. Whereas driver mutations in protein-coding genes can be distinguished from passenger mutations based on their recurrence, non-coding mutations are usually not recurrent at the same position. Therefore, it is still unclear how to identify cis-regulatory driver mutations, particularly when chromatin data from the same patient is not available, thus relying only on sequence and expression information. Here we use machine-learning methods to predict functional regulatory regions using sequence information alone, and compare the predicted activity of the mutated region with the reference sequence. This way we define the Predicted Regulatory Impact of a Mutation in an Enhancer (PRIME). We find that the recently identified driver mutation in the TAL1 enhancer has a high PRIME score, representing a "gain-of-target" for MYB, whereas the highly recurrent TERT promoter mutation has a surprisingly low PRIME score. We trained Random Forest models for 45 cancer-related transcription factors, and used these to score variations in the HeLa genome and somatic mutations across more than five hundred cancer genomes. Each model predicts only a small fraction of non-coding mutations with a potential impact on the function of the encompassing regulatory region. Nevertheless, as these few candidate driver mutations are often linked to gains in chromatin activity and gene expression, they may contribute to the oncogenic program by altering the expression levels of specific oncogenes and tumor suppressor genes. PMID:26562774

  12. Recurrent modification of a conserved cis-regulatory element underlies fruit fly pigmentation diversity.

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    William A Rogers

    2013-08-01

    Full Text Available The development of morphological traits occurs through the collective action of networks of genes connected at the level of gene expression. As any node in a network may be a target of evolutionary change, the recurrent targeting of the same node would indicate that the path of evolution is biased for the relevant trait and network. Although examples of parallel evolution have implicated recurrent modification of the same gene and cis-regulatory element (CRE, little is known about the mutational and molecular paths of parallel CRE evolution. In Drosophila melanogaster fruit flies, the Bric-à-brac (Bab transcription factors control the development of a suite of sexually dimorphic traits on the posterior abdomen. Female-specific Bab expression is regulated by the dimorphic element, a CRE that possesses direct inputs from body plan (ABD-B and sex-determination (DSX transcription factors. Here, we find that the recurrent evolutionary modification of this CRE underlies both intraspecific and interspecific variation in female pigmentation in the melanogaster species group. By reconstructing the sequence and regulatory activity of the ancestral Drosophila melanogaster dimorphic element, we demonstrate that a handful of mutations were sufficient to create independent CRE alleles with differing activities. Moreover, intraspecific and interspecific dimorphic element evolution proceeded with little to no alterations to the known body plan and sex-determination regulatory linkages. Collectively, our findings represent an example where the paths of evolution appear biased to a specific CRE, and drastic changes in function were accompanied by deep conservation of key regulatory linkages.

  13. Recurrent Modification of a Conserved Cis-Regulatory Element Underlies Fruit Fly Pigmentation Diversity

    Science.gov (United States)

    Rogers, William A.; Salomone, Joseph R.; Tacy, David J.; Camino, Eric M.; Davis, Kristen A.; Rebeiz, Mark; Williams, Thomas M.

    2013-01-01

    The development of morphological traits occurs through the collective action of networks of genes connected at the level of gene expression. As any node in a network may be a target of evolutionary change, the recurrent targeting of the same node would indicate that the path of evolution is biased for the relevant trait and network. Although examples of parallel evolution have implicated recurrent modification of the same gene and cis-regulatory element (CRE), little is known about the mutational and molecular paths of parallel CRE evolution. In Drosophila melanogaster fruit flies, the Bric-à-brac (Bab) transcription factors control the development of a suite of sexually dimorphic traits on the posterior abdomen. Female-specific Bab expression is regulated by the dimorphic element, a CRE that possesses direct inputs from body plan (ABD-B) and sex-determination (DSX) transcription factors. Here, we find that the recurrent evolutionary modification of this CRE underlies both intraspecific and interspecific variation in female pigmentation in the melanogaster species group. By reconstructing the sequence and regulatory activity of the ancestral Drosophila melanogaster dimorphic element, we demonstrate that a handful of mutations were sufficient to create independent CRE alleles with differing activities. Moreover, intraspecific and interspecific dimorphic element evolution proceeded with little to no alterations to the known body plan and sex-determination regulatory linkages. Collectively, our findings represent an example where the paths of evolution appear biased to a specific CRE, and drastic changes in function were accompanied by deep conservation of key regulatory linkages. PMID:24009528

  14. Bioinformatic analysis of cis-regulatory interactions between progesterone and estrogen receptors in breast cancer

    Directory of Open Access Journals (Sweden)

    Matloob Khushi

    2014-11-01

    Full Text Available Chromatin factors interact with each other in a cell and sequence-specific manner in order to regulate transcription and a wealth of publically available datasets exists describing the genomic locations of these interactions. Our recently published BiSA (Binding Sites Analyser database contains transcription factor binding locations and epigenetic modifications collected from published studies and provides tools to analyse stored and imported data. Using BiSA we investigated the overlapping cis-regulatory role of estrogen receptor alpha (ERα and progesterone receptor (PR in the T-47D breast cancer cell line. We found that ERα binding sites overlap with a subset of PR binding sites. To investigate further, we re-analysed raw data to remove any biases introduced by the use of distinct tools in the original publications. We identified 22,152 PR and 18,560 ERα binding sites (<5% false discovery rate with 4,358 overlapping regions among the two datasets. BiSA statistical analysis revealed a non-significant overall overlap correlation between the two factors, suggesting that ERα and PR are not partner factors and do not require each other for binding to occur. However, Monte Carlo simulation by Binary Interval Search (BITS, Relevant Distance, Absolute Distance, Jaccard and Projection tests by Genometricorr revealed a statistically significant spatial correlation of binding regions on chromosome between the two factors. Motif analysis revealed that the shared binding regions were enriched with binding motifs for ERα, PR and a number of other transcription and pioneer factors. Some of these factors are known to co-locate with ERα and PR binding. Therefore spatially close proximity of ERα binding sites with PR binding sites suggests that ERα and PR, in general function independently at the molecular level, but that their activities converge on a specific subset of transcriptional targets.

  15. Combining computational prediction of cis-regulatory elements with a new enhancer assay to efficiently label neuronal structures in the medaka fish.

    Directory of Open Access Journals (Sweden)

    Emmanuel Mongin

    Full Text Available The developing vertebrate nervous system contains a remarkable array of neural cells organized into complex, evolutionarily conserved structures. The labeling of living cells in these structures is key for the understanding of brain development and function, yet the generation of stable lines expressing reporter genes in specific spatio-temporal patterns remains a limiting step. In this study we present a fast and reliable pipeline to efficiently generate a set of stable lines expressing a reporter gene in multiple neuronal structures in the developing nervous system in medaka. The pipeline combines both the accurate computational genome-wide prediction of neuronal specific cis-regulatory modules (CRMs and a newly developed experimental setup to rapidly obtain transgenic lines in a cost-effective and highly reproducible manner. 95% of the CRMs tested in our experimental setup show enhancer activity in various and numerous neuronal structures belonging to all major brain subdivisions. This pipeline represents a significant step towards the dissection of embryonic neuronal development in vertebrates.

  16. ChIP-Seq-Annotated Heliconius erato Genome Highlights Patterns of cis-Regulatory Evolution in Lepidoptera.

    Science.gov (United States)

    Lewis, James J; van der Burg, Karin R L; Mazo-Vargas, Anyi; Reed, Robert D

    2016-09-13

    Uncovering phylogenetic patterns of cis-regulatory evolution remains a fundamental goal for evolutionary and developmental biology. Here, we characterize the evolution of regulatory loci in butterflies and moths using chromatin immunoprecipitation sequencing (ChIP-seq) annotation of regulatory elements across three stages of head development. In the process we provide a high-quality, functionally annotated genome assembly for the butterfly, Heliconius erato. Comparing cis-regulatory element conservation across six lepidopteran genomes, we find that regulatory sequences evolve at a pace similar to that of protein-coding regions. We also observe that elements active at multiple developmental stages are markedly more conserved than elements with stage-specific activity. Surprisingly, we also find that stage-specific proximal and distal regulatory elements evolve at nearly identical rates. Our study provides a benchmark for genome-wide patterns of regulatory element evolution in insects, and it shows that developmental timing of activity strongly predicts patterns of regulatory sequence evolution. PMID:27626657

  17. MotifCombinator: a web-based tool to search for combinations of cis-regulatory motifs

    Directory of Open Access Journals (Sweden)

    Tsunoda Tatsuhiko

    2007-03-01

    Full Text Available Abstract Background A combination of multiple types of transcription factors and cis-regulatory elements is often required for gene expression in eukaryotes, and the combinatorial regulation confers specific gene expression to tissues or environments. To reveal the combinatorial regulation, computational methods are developed that efficiently infer combinations of cis-regulatory motifs that are important for gene expression as measured by DNA microarrays. One promising type of computational method is to utilize regression analysis between expression levels and scores of motifs in input sequences. This type takes full advantage of information on expression levels because it does not require that the expression level of each gene be dichotomized according to whether or not it reaches a certain threshold level. However, there is no web-based tool that employs regression methods to systematically search for motif combinations and that practically handles combinations of more than two or three motifs. Results We here introduced MotifCombinator, an online tool with a user-friendly interface, to systematically search for combinations composed of any number of motifs based on regression methods. The tool utilizes well-known regression methods (the multivariate linear regression, the multivariate adaptive regression spline or MARS, and the multivariate logistic regression method for this purpose, and uses the genetic algorithm to search for combinations composed of any desired number of motifs. The visualization systems in this tool help users to intuitively grasp the process of the combination search, and the backup system allows users to easily stop and restart calculations that are expected to require large computational time. This tool also provides preparatory steps needed for systematic combination search – i.e., selecting single motifs to constitute combinations and cutting out redundant similar motifs based on clustering analysis. Conclusion

  18. Characterization and identification of cis-regulatory elements in Arabidopsis based on single-nucleotide polymorphism information.

    Science.gov (United States)

    Korkuc, Paula; Schippers, Jos H M; Walther, Dirk

    2014-01-01

    Identifying regulatory elements and revealing their role in gene expression regulation remains a central goal of plant genome research. We exploited the detailed genomic sequencing information of a large number of Arabidopsis (Arabidopsis thaliana) accessions to characterize known and to identify novel cis-regulatory elements in gene promoter regions of Arabidopsis by relying on conservation as the hallmark signal of functional relevance. Based on the genomic layout and the obtained density profiles of single-nucleotide polymorphisms (SNPs) in sequence regions upstream of transcription start sites, the average length of promoter regions in Arabidopsis could be established at 500 bp. Genes associated with high degrees of variability of their respective upstream regions are preferentially involved in environmental response and signaling processes, while low levels of promoter SNP density are common among housekeeping genes. Known cis-elements were found to exhibit a decreased SNP density than sequence regions not associated with known motifs. For 15 known cis-element motifs, strong positional preferences relative to the transcription start site were detected based on their promoter SNP density profiles. Five novel candidate cis-element motifs were identified as consensus motifs of 17 sequence hexamers exhibiting increased sequence conservation combined with evidence of positional preferences, annotation information, and functional relevance for inducing correlated gene expression. Our study demonstrates that the currently available resolution of SNP data offers novel ways for the identification of functional genomic elements and the characterization of gene promoter sequences. PMID:24204023

  19. Cis-regulatory programs in the development and evolution of vertebrate paired appendages.

    Science.gov (United States)

    Gehrke, Andrew R; Shubin, Neil H

    2016-09-01

    Differential gene expression is the core of development, mediating the genetic changes necessary for determining cell identity. The regulation of gene activity by cis-acting elements (e.g., enhancers) is a crucial mechanism for determining differential gene activity by precise control of gene expression in embryonic space and time. Modifications to regulatory regions can have profound impacts on phenotype, and therefore developmental and evolutionary biologists have increasingly focused on elucidating the transcriptional control of genes that build and pattern body plans. Here, we trace the evolutionary history of transcriptional control of three loci key to vertebrate appendage development (Fgf8, Shh, and HoxD/A). Within and across these regulatory modules, we find both complex and flexible regulation in contrast with more fixed enhancers that appear unchanged over vast timescales of vertebrate evolution. The transcriptional control of vertebrate appendage development was likely already incredibly complex in the common ancestor of fish, implying that subtle changes to regulatory networks were more likely responsible for alterations in phenotype rather than the de novo addition of whole regulatory domains. Finally, we discuss the dangers of relying on inter-species transgenesis when testing enhancer function, and call for more controlled regulatory swap experiments when inferring the evolutionary history of enhancer elements. PMID:26783722

  20. Shared Enhancer Activity in the Limbs and Phallus and Functional Divergence of a Limb-Genital cis-Regulatory Element in Snakes.

    Science.gov (United States)

    Infante, Carlos R; Mihala, Alexandra G; Park, Sungdae; Wang, Jialiang S; Johnson, Kenji K; Lauderdale, James D; Menke, Douglas B

    2015-10-12

    The amniote phallus and limbs differ dramatically in their morphologies but share patterns of signaling and gene expression in early development. Thus far, the extent to which genital and limb transcriptional networks also share cis-regulatory elements has remained unexplored. We show that many limb enhancers are retained in snake genomes, suggesting that these elements may function in non-limb tissues. Consistent with this, our analysis of cis-regulatory activity in mice and Anolis lizards reveals that patterns of enhancer activity in embryonic limbs and genitalia overlap heavily. In mice, deletion of HLEB, an enhancer of Tbx4, produces defects in hindlimbs and genitalia, establishing the importance of this limb-genital enhancer for development of these different appendages. Further analyses demonstrate that the HLEB of snakes has lost hindlimb enhancer function while retaining genital activity. Our findings identify roles for Tbx4 in genital development and highlight deep similarities in cis-regulatory activity between limbs and genitalia. PMID:26439399

  1. Decoding a signature-based model of transcription cofactor recruitment dictated by cardinal cis-regulatory elements in proximal promoter regions.

    Directory of Open Access Journals (Sweden)

    Christopher Benner

    2013-11-01

    Full Text Available Genome-wide maps of DNase I hypersensitive sites (DHSs reveal that most human promoters contain perpetually active cis-regulatory elements between -150 bp and +50 bp (-150/+50 bp relative to the transcription start site (TSS. Transcription factors (TFs recruit cofactors (chromatin remodelers, histone/protein-modifying enzymes, and scaffold proteins to these elements in order to organize the local chromatin structure and coordinate the balance of post-translational modifications nearby, contributing to the overall regulation of transcription. However, the rules of TF-mediated cofactor recruitment to the -150/+50 bp promoter regions remain poorly understood. Here, we provide evidence for a general model in which a series of cis-regulatory elements (here termed 'cardinal' motifs prefer acting individually, rather than in fixed combinations, within the -150/+50 bp regions to recruit TFs that dictate cofactor signatures distinctive of specific promoter subsets. Subsequently, human promoters can be subclassified based on the presence of cardinal elements and their associated cofactor signatures. In this study, furthermore, we have focused on promoters containing the nuclear respiratory factor 1 (NRF1 motif as the cardinal cis-regulatory element and have identified the pervasive association of NRF1 with the cofactor lysine-specific demethylase 1 (LSD1/KDM1A. This signature might be distinctive of promoters regulating nuclear-encoded mitochondrial and other particular genes in at least some cells. Together, we propose that decoding a signature-based, expanded model of control at proximal promoter regions should lead to a better understanding of coordinated regulation of gene transcription.

  2. ‘In silico expression analysis’, a novel PathoPlant web tool to identify abiotic and biotic stress conditions associated with specific cis-regulatory sequences

    Science.gov (United States)

    Machens, Fabian; Brill, Yuri; Romanov, Artyom; Bülow, Lorenz; Hehl, Reinhard

    2014-01-01

    Using bioinformatics, putative cis-regulatory sequences can be easily identified using pattern recognition programs on promoters of specific gene sets. The abundance of predicted cis-sequences is a major challenge to associate these sequences with a possible function in gene expression regulation. To identify a possible function of the predicted cis-sequences, a novel web tool designated ‘in silico expression analysis’ was developed that correlates submitted cis-sequences with gene expression data from Arabidopsis thaliana. The web tool identifies the A. thaliana genes harbouring the sequence in a defined promoter region and compares the expression of these genes with microarray data. The result is a hierarchy of abiotic and biotic stress conditions to which these genes are most likely responsive. When testing the performance of the web tool, known cis-regulatory sequences were submitted to the ‘in silico expression analysis’ resulting in the correct identification of the associated stress conditions. When using a recently identified novel elicitor-responsive sequence, a WT-box (CGACTTTT), the ‘in silico expression analysis’ predicts that genes harbouring this sequence in their promoter are most likely Botrytis cinerea induced. Consistent with this prediction, the strongest induction of a reporter gene harbouring this sequence in the promoter is observed with B. cinerea in transgenic A. thaliana. Database URL: http://www.pathoplant.de/expression_analysis.php. PMID:24727366

  3. A cis-regulatory sequence from a short intergenic region gives rise to a strong microbe-associated molecular pattern-responsive synthetic promoter.

    Science.gov (United States)

    Lehmeyer, Mona; Hanko, Erik K R; Roling, Lena; Gonzalez, Lilian; Wehrs, Maren; Hehl, Reinhard

    2016-06-01

    The high gene density in Arabidopsis thaliana leaves only relatively short intergenic regions for potential cis-regulatory sequences. To learn more about the regulation of genes harbouring only very short upstream intergenic regions, this study investigates a recently identified novel microbe-associated molecular pattern (MAMP)-responsive cis-sequence located within the 101 bp long intergenic region upstream of the At1g13990 gene. It is shown that the cis-regulatory sequence is sufficient for MAMP-responsive reporter gene activity in the context of its native promoter. The 3' UTR of the upstream gene has a quantitative effect on gene expression. In context of a synthetic promoter, the cis-sequence is shown to achieve a strong increase in reporter gene activity as a monomer, dimer and tetramer. Mutation analysis of the cis-sequence determined the specific nucleotides required for gene expression activation. In transgenic A. thaliana the synthetic promoter harbouring a tetramer of the cis-sequence not only drives strong pathogen-responsive reporter gene expression but also shows a high background activity. The results of this study contribute to our understanding how genes with very short upstream intergenic regions are regulated and how these regions can serve as a source for MAMP-responsive cis-sequences for synthetic promoter design. PMID:26833485

  4. 'In silico expression analysis', a novel PathoPlant web tool to identify abiotic and biotic stress conditions associated with specific cis-regulatory sequences.

    Science.gov (United States)

    Bolívar, Julio C; Machens, Fabian; Brill, Yuri; Romanov, Artyom; Bülow, Lorenz; Hehl, Reinhard

    2014-01-01

    Using bioinformatics, putative cis-regulatory sequences can be easily identified using pattern recognition programs on promoters of specific gene sets. The abundance of predicted cis-sequences is a major challenge to associate these sequences with a possible function in gene expression regulation. To identify a possible function of the predicted cis-sequences, a novel web tool designated 'in silico expression analysis' was developed that correlates submitted cis-sequences with gene expression data from Arabidopsis thaliana. The web tool identifies the A. thaliana genes harbouring the sequence in a defined promoter region and compares the expression of these genes with microarray data. The result is a hierarchy of abiotic and biotic stress conditions to which these genes are most likely responsive. When testing the performance of the web tool, known cis-regulatory sequences were submitted to the 'in silico expression analysis' resulting in the correct identification of the associated stress conditions. When using a recently identified novel elicitor-responsive sequence, a WT-box (CGACTTTT), the 'in silico expression analysis' predicts that genes harbouring this sequence in their promoter are most likely Botrytis cinerea induced. Consistent with this prediction, the strongest induction of a reporter gene harbouring this sequence in the promoter is observed with B. cinerea in transgenic A. thaliana. DATABASE URL: http://www.pathoplant.de/expression_analysis.php. PMID:24727366

  5. An in vivo cis-regulatory screen at the type 2 diabetes associated TCF7L2 locus identifies multiple tissue-specific enhancers.

    Directory of Open Access Journals (Sweden)

    Daniel Savic

    Full Text Available Genome-wide association studies (GWAS have repeatedly shown an association between non-coding variants in the TCF7L2 locus and risk for type 2 diabetes (T2D, implicating a role for cis-regulatory variation within this locus in disease etiology. Supporting this hypothesis, we previously localized complex regulatory activity to the TCF7L2 T2D-associated interval using an in vivo bacterial artificial chromosome (BAC enhancer-trapping reporter strategy. To follow-up on this broad initial survey of the TCF7L2 regulatory landscape, we performed a fine-mapping enhancer scan using in vivo mouse transgenic reporter assays. We functionally interrogated approximately 50% of the sequences within the T2D-associated interval, utilizing sequence conservation within this 92-kb interval to determine the regulatory potential of all evolutionary conserved sequences that exhibited conservation to the non-eutherian mammal opossum. Included in this study was a detailed functional interrogation of sequences spanning both protective and risk alleles of single nucleotide polymorphism (SNP rs7903146, which has exhibited allele-specific enhancer function in pancreatic beta cells. Using these assays, we identified nine segments regulating various aspects of the TCF7L2 expression profile and that constitute nearly 70% of the sequences tested. These results highlight the regulatory complexity of this interval and support the notion that a TCF7L2 cis-regulatory disruption leads to T2D predisposition.

  6. Preaxial polydactyly/triphalangeal thumb is associated with changed transcription factor-binding affinity in a family with a novel point mutation in the long-range cis-regulatory element ZRS

    DEFF Research Database (Denmark)

    Farooq, Muhammad; Troelsen, Jesper T; Boyd, Mette;

    2010-01-01

    A cis-regulatory sequence also known as zone of polarizing activity (ZPA) regulatory sequence (ZRS) located in intron 5 of LMBR1 is essential for expression of sonic hedgehog (SHH) in the developing posterior limb bud mesenchyme. Even though many point mutations causing preaxial duplication defects...

  7. Cis-regulatory control of the nuclear receptor Coup-TF gene in the sea urchin Paracentrotus lividus embryo.

    Directory of Open Access Journals (Sweden)

    Lamprini G Kalampoki

    Full Text Available Coup-TF, an orphan member of the nuclear receptor super family, has a fundamental role in the development of metazoan embryos. The study of the gene's regulatory circuit in the sea urchin embryo will facilitate the placement of this transcription factor in the well-studied embryonic Gene Regulatory Network (GRN. The Paracentrotus lividus Coup-TF gene (PlCoup-TF is expressed throughout embryonic development preferentially in the oral ectoderm of the gastrula and the ciliary band of the pluteus stage. Two overlapping λ genomic clones, containing three exons and upstream sequences of PlCoup-TF, were isolated from a genomic library. The transcription initiation site was determined and 5' deletions and individual segments of a 1930 bp upstream region were placed ahead of a GFP reporter cassette and injected into fertilized P.lividus eggs. Module a (-532 to -232, was necessary and sufficient to confer ciliary band expression to the reporter. Comparison of P.lividus and Strongylocentrotus purpuratus upstream Coup-TF sequences, revealed considerable conservation, but none within module a. 5' and internal deletions into module a, defined a smaller region that confers ciliary band specific expression. Putative regulatory cis-acting elements (RE1, RE2 and RE3 within module a, were specifically bound by proteins in sea urchin embryonic nuclear extracts. Site-specific mutagenesis of these elements resulted in loss of reporter activity (RE1 or ectopic expression (RE2, RE3. It is proposed that sea urchin transcription factors, which bind these three regulatory sites, are necessary for spatial and quantitative regulation of the PlCoup-TF gene at pluteus stage sea urchin embryos. These findings lead to the future identification of these factors and to the hierarchical positioning of PlCoup-TF within the embryonic GRN.

  8. Maps of cis-Regulatory Nodes in Megabase Long Genome Segments are an Inevitable Intermediate Step Toward Whole Genome Functional Mapping.

    Science.gov (United States)

    Nikolaev, Lev G; Akopov, Sergey B; Chernov, Igor P; Sverdlov, Eugene D

    2007-04-01

    The availability of complete human and other metazoan genome sequences has greatly facilitated positioning and analysis of various genomic functional elements, with initial emphasis on coding sequences. However, complete functional maps of sequenced eukaryotic genomes should include also positions of all non-coding regulatory elements. Unfortunately, experimental data on genomic positions of a multitude of regulatory sequences, such as enhancers, silencers, insulators, transcription terminators, and replication origins are very limited, especially at the whole genome level. Since most genomic regulatory elements (e.g. enhancers) are generally gene-, tissue-, or cell-specific, the prediction of these elements by computational methods is difficult and often ambiguous. Therefore, the development of high-throughput experimental approaches for identifying and mapping genomic functional elements is highly desirable. At the same time, the creation of whole-genome map of hundreds of thousands of regulatory elements in several hundreds of tissue/cell types is presently far beyond our capabilities. A possible alternative for the whole genome approach is to concentrate efforts on individual genomic segments and then to integrate the data obtained into a whole genome functional map. Moreover, the maps of polygenic fragments with functional cis-regulatory elements would provide valuable data on complex regulatory systems, including their variability and evolution. Here, we reviewed experimental approaches to the realization of these ideas, including our own developments of experimental techniques for selection of cis-acting functionally active DNA fragments from large (megabase-sized) segments of mammalian genomes. PMID:18660850

  9. Maps of cis-Regulatory Nodes in Megabase Long Genome Segments are an Inevitable Intermediate Step Toward Whole Genome Functional Mapping

    Science.gov (United States)

    Nikolaev, Lev G; Akopov, Sergey B; Chernov, Igor P; Sverdlov, Eugene D

    2007-01-01

    The availability of complete human and other metazoan genome sequences has greatly facilitated positioning and analysis of various genomic functional elements, with initial emphasis on coding sequences. However, complete functional maps of sequenced eukaryotic genomes should include also positions of all non-coding regulatory elements. Unfortunately, experimental data on genomic positions of a multitude of regulatory sequences, such as enhancers, silencers, insulators, transcription terminators, and replication origins are very limited, especially at the whole genome level. Since most genomic regulatory elements (e.g. enhancers) are generally gene-, tissue-, or cell-specific, the prediction of these elements by computational methods is difficult and often ambiguous. Therefore, the development of high-throughput experimental approaches for identifying and mapping genomic functional elements is highly desirable. At the same time, the creation of whole-genome map of hundreds of thousands of regulatory elements in several hundreds of tissue/cell types is presently far beyond our capabilities. A possible alternative for the whole genome approach is to concentrate efforts on individual genomic segments and then to integrate the data obtained into a whole genome functional map. Moreover, the maps of polygenic fragments with functional cis-regulatory elements would provide valuable data on complex regulatory systems, including their variability and evolution. Here, we reviewed experimental approaches to the realization of these ideas, including our own developments of experimental techniques for selection of cis-acting functionally active DNA fragments from large (megabase-sized) segments of mammalian genomes. PMID:18660850

  10. Promoter analysis reveals cis-regulatory motifs associated with the expression of the WRKY transcription factor CrWRKY1 in Catharanthus roseus.

    Science.gov (United States)

    Yang, Zhirong; Patra, Barunava; Li, Runzhi; Pattanaik, Sitakanta; Yuan, Ling

    2013-12-01

    WRKY transcription factors (TFs) are emerging as an important group of regulators of plant secondary metabolism. However, the cis-regulatory elements associated with their regulation have not been well characterized. We have previously demonstrated that CrWRKY1, a member of subgroup III of the WRKY TF family, regulates biosynthesis of terpenoid indole alkaloids in the ornamental and medicinal plant, Catharanthus roseus. Here, we report the isolation and functional characterization of the CrWRKY1 promoter. In silico analysis of the promoter sequence reveals the presence of several potential TF binding motifs, indicating the involvement of additional TFs in the regulation of the TIA pathway. The CrWRKY1 promoter can drive the expression of a β-glucuronidase (GUS) reporter gene in native (C. roseus protoplasts and transgenic hairy roots) and heterologous (transgenic tobacco seedlings) systems. Analysis of 5'- or 3'-end deletions indicates that the sequence located between positions -140 to -93 bp and -3 to +113 bp, relative to the transcription start site, is critical for promoter activity. Mutation analysis shows that two overlapping as-1 elements and a CT-rich motif contribute significantly to promoter activity. The CrWRKY1 promoter is induced in response to methyl jasmonate (MJ) treatment and the promoter region between -230 and -93 bp contains a putative MJ-responsive element. The CrWRKY1 promoter can potentially be used as a tool to isolate novel TFs involved in the regulation of the TIA pathway. PMID:23979312

  11. Distinct cis regulatory elements govern the expression of TAG1 in embryonic sensory ganglia and spinal cord.

    Directory of Open Access Journals (Sweden)

    Yoav Hadas

    Full Text Available Cell fate commitment of spinal progenitor neurons is initiated by long-range, midline-derived, morphogens that regulate an array of transcription factors that, in turn, act sequentially or in parallel to control neuronal differentiation. Included among these are transcription factors that regulate the expression of receptors for guidance cues, thereby determining axonal trajectories. The Ig/FNIII superfamily molecules TAG1/Axonin1/CNTN2 (TAG1 and Neurofascin (Nfasc are co-expressed in numerous neuronal cell types in the CNS and PNS - for example motor, DRG and interneurons - both promote neurite outgrowth and both are required for the architecture and function of nodes of Ranvier. The genes encoding TAG1 and Nfasc are adjacent in the genome, an arrangement which is evolutionarily conserved. To study the transcriptional network that governs TAG1 and Nfasc expression in spinal motor and commissural neurons, we set out to identify cis elements that regulate their expression. Two evolutionarily conserved DNA modules, one located between the Nfasc and TAG1 genes and the second directly 5' to the first exon and encompassing the first intron of TAG1, were identified that direct complementary expression to the CNS and PNS, respectively, of the embryonic hindbrain and spinal cord. Sequential deletions and point mutations of the CNS enhancer element revealed a 130bp element containing three conserved E-boxes required for motor neuron expression. In combination, these two elements appear to recapitulate a major part of the pattern of TAG1 expression in the embryonic nervous system.

  12. PlantPAN: Plant promoter analysis navigator, for identifying combinatorial cis-regulatory elements with distance constraint in plant gene groups

    Directory of Open Access Journals (Sweden)

    Huang Hsien-Da

    2008-11-01

    Full Text Available Abstract Background The elucidation of transcriptional regulation in plant genes is important area of research for plant scientists, following the mapping of various plant genomes, such as A. thaliana, O. sativa and Z. mays. A variety of bioinformatic servers or databases of plant promoters have been established, although most have been focused only on annotating transcription factor binding sites in a single gene and have neglected some important regulatory elements (tandem repeats and CpG/CpNpG islands in promoter regions. Additionally, the combinatorial interaction of transcription factors (TFs is important in regulating the gene group that is associated with the same expression pattern. Therefore, a tool for detecting the co-regulation of transcription factors in a group of gene promoters is required. Results This study develops a database-assisted system, PlantPAN (Plant Promoter Analysis Navigator, for recognizing combinatorial cis-regulatory elements with a distance constraint in sets of plant genes. The system collects the plant transcription factor binding profiles from PLACE, TRANSFAC (public release 7.0, AGRIS, and JASPER databases and allows users to input a group of gene IDs or promoter sequences, enabling the co-occurrence of combinatorial transcription factor binding sites (TFBSs within a defined distance (20 bp to 200 bp to be identified. Furthermore, the new resource enables other regulatory features in a plant promoter, such as CpG/CpNpG islands and tandem repeats, to be displayed. The regulatory elements in the conserved regions of the promoters across homologous genes are detected and presented. Conclusion In addition to providing a user-friendly input/output interface, PlantPAN has numerous advantages in the analysis of a plant promoter. Several case studies have established the effectiveness of PlantPAN. This novel analytical resource is now freely available at http://PlantPAN.mbc.nctu.edu.tw.

  13. Exploration of external light trapping for photovoltaic modules.

    Science.gov (United States)

    van Dijk, Lourens; van de Groep, Jorik; Di Vece, Marcel; Schropp, Ruud E I

    2016-07-11

    The reflection of incident sunlight by photovoltaic modules prevents them from reaching their theoretical energy conversion limit. We explore the effectiveness of a universal external light trap that can tackle this reflection loss. A unique feature of external light traps is their capability to simultaneously recycle various broadband sources of reflection on the module level, such as the reflection from the metal front grid, the front interfaces, the reflective backside of the cell, and the white back sheet. The reflected light is recycled in the space between the solar cell and a mirror above the solar cell. A concentrator funnels the light into this cage through a small aperture in the mirror. As a proof-of-principle experiment, a significant reflectance reduction of a bare crystalline silicon (c-Si) photodiode is demonstrated. In contrast to conventional light trapping methods, external light trapping does not induce any damage to the active solar cell material. Moreover, this is a universally applicable technology that enables the use of thin and planar solar cells of superior electrical quality that were so far hindered by limited optical absorption. We considered several trap designs and identified fabrication issues. A series of prototype millimeter-scale external metal light traps were milled and applied on an untextured c-Si photodiode, which is used as a model for future thin solar cells. We determined the concentrator transmittance and analyzed the effect of both the concentration factor and cage height on the absorptance and spatial intensity distribution on the surface of the solar cell. This relatively simple and comprehensive light management solution can be a promising candidate for highly efficient solar modules using thin c-Si solar cells. PMID:27410902

  14. The Novelty Exploration Bonus and Its Attentional Modulation

    Science.gov (United States)

    Krebs, Ruth M.; Schott, Bjorn H.; Schutze, Hartmut; Duzel, Emrah

    2009-01-01

    We hypothesized that novel stimuli represent salient learning signals that can motivate "exploration" in search for potential rewards. In computational theories of reinforcement learning, this is referred to as the novelty "exploration bonus" for rewards. If true, stimulus novelty should enhance the reward anticipation signals in brain areas that…

  15. Formation of Regulatory Modules by Local Sequence Duplication

    OpenAIRE

    Nourmohammad, Armita; Lässig, Michael

    2011-01-01

    Author Summary Since Jacob and Monod stressed the importance of gene regulation in evolution, our understanding of the mechanisms of regulation has substantially advanced. In higher eukaryotes, genes often have complex regulatory input, which is encoded in cis-regulatory sequence with multiple transcription factor binding sites. However, the modes of genome evolution generating regulatory complexity are much less understood. This study reports a surprising finding: in fly regulatory modules, ...

  16. New and under explored epigenetic modulators in search of new paradigms.

    Science.gov (United States)

    Alam, Mohammad Abrar; Reddy, Yeruva Suman; Ali, Mohamad Akbar

    2015-01-01

    Aberrant regulation of epigenetic pathways causes many diseases including aging, cancer, diabetes, viral pathogenesis, drug addiction etc. and it has been estimated that epigenetic aberrations are at least ten to forty times more frequent in cancers than genetic mutations. Present epigenetic modulators hold great promise for a variety of diseases, and important tools for biological applications but these molecules have many dose limiting toxicities and existing paradigms lack desired efficacy. Synthesis and biological studies of epigenetic modulators have been attractive targets for medicinal and synthetic organic chemists in recent years. This review article provides deep insight into the new and under explored epigenetic modulators. These molecules have the potential to be used as unique template with novel pharmacophores. PMID:25256243

  17. Exploration

    Science.gov (United States)

    Wilburn, D.R.; Porter, K.E.

    1999-01-01

    This summary of international nonfuel mineral exploration activities for 1998 draws on available data from literature, industry and US Geological Survey (USGS) specialists. Data on exploration budgets by region and commodity are reported, significant mineral discoveries and exploration target areas are identified and government programs affecting the mineral exploration industry are discussed. Inferences and observations on mineral industry direction are drawn from these data and discussions.

  18. Thermal Control System Development to Support the Crew Exploration Vehicle and Lunar Surface Access Module

    Science.gov (United States)

    Anderson, Molly; Westheimer, David

    2006-01-01

    All space vehicles or habitats require thermal management to maintain a safe and operational environment for both crew and hardware. Active Thermal Control Systems (ATCS) perform the functions of acquiring heat from both crew and hardware within a vehicle, transporting that heat throughout the vehicle, and finally rejecting that energy into space. Almost all of the energy used in a space vehicle eventually turns into heat, which must be rejected in order to maintain an energy balance and temperature control of the vehicle. For crewed vehicles, Active Thermal Control Systems are pumped fluid loops that are made up of components designed to perform these functions. NASA has recently evaluated all of the agency s technology development work and identified key areas that must be addressed to aid in the successful development of a Crew Exploration Vehicle (CEV) and a Lunar Surface Access Module (LSAM). The technologies that have been selected and are currently under development include: fluids that enable single loop ATCS architectures, a gravity insensitive vapor compression cycle heat pump, a sublimator with reduced sensitivity to feedwater contamination, an evaporative heat sink that can operate in multiple ambient pressure environments, a compact spray evaporator, and lightweight radiators that take advantage of carbon composites and advanced optical coatings.

  19. 5-HTTLPR modulates the recognition accuracy and exploration of emotional facial expressions

    Directory of Open Access Journals (Sweden)

    Sabrina eBoll

    2014-07-01

    Full Text Available Individual genetic differences in the serotonin transporter-linked polymorphic region (5-HTTLPR have been associated with variations in the sensitivity to social and emotional cues as well as altered amygdala reactivity to facial expressions of emotion. Amygdala activation has further been shown to trigger gaze changes towards diagnostically relevant facial features. The current study examined whether altered socio-emotional reactivity in variants of the 5-HTTLPR promoter polymorphism reflects individual differences in attending to diagnostic features of facial expressions. For this purpose, visual exploration of emotional facial expressions was compared between a low (n=39 and a high (n=40 5-HTT expressing group of healthy human volunteers in an eye tracking paradigm. Emotional faces were presented while manipulating the initial fixation such that saccadic changes towards the eyes and towards the mouth could be identified. We found that the low versus the high 5-HTT group demonstrated greater accuracy with regard to emotion classifications, particularly when faces were presented for a longer duration. No group differences in gaze orientation towards diagnostic facial features could be observed. However, participants in the low 5-HTT group exhibited more and faster fixation changes for certain emotions when faces were presented for a longer duration and overall face fixation times were reduced for this genotype group. These results suggest that the 5-HTT gene influences social perception by modulating the general vigilance to social cues rather than selectively affecting the pre-attentive detection of diagnostic facial features.

  20. Exploration

    International Nuclear Information System (INIS)

    Oil and gas exploration is a unique kind of business. Businesses providing a vast and ever-changing panoply of products to markets are a focus of several disciplines' energetic study and analysis. The product inventory problem is robust, pertinent, and meaningful, and it merits the voluminous and protracted attention received from keen business practitioners. Prototypical business practitioners, be they trained by years of business hurly-burly, or sophisticated MBAs with arrays of mathematical algorithms and computers, are not normally prepared, however, to recognize the unique nature of exploration's inventories. Put together such a business practitioner with an explorationist and misunderstandings, hidden and open, are inevitable and predictably rife. The first purpose of this paper is to articulate the inherited inventory handling paradigms of business practitioners in relation to exploration's inventories. To do so, standard pedagogy in business administration is used and a case study of an exploration venture is presented. A second purpose is to show the burdens that the misunderstandings create. The result is not just business plans that go awry, but public policies that have effects opposite from those intended

  1. EXPLORING OCCUPATIONAL OPPORTUNITIES IN ORNAMENTAL HORTICULTURE. HORTICULTURE-SERVICE OCCUPATIONS, MODULE NO. 1.

    Science.gov (United States)

    Ohio State Univ., Columbus. Center for Vocational and Technical Education.

    THE MAJOR OBJECTIVE OF THIS MODULE IS TO DEVELOP STUDENT UNDERSTANDING OF OCCUPATIONAL OPPORTUNITIES AVAILABLE IN ORNAMENTAL HORTICULTURE. IT IS ONE OF A SERIES DESIGNED TO PREPARE HIGH SCHOOL STUDENTS FOR HORTICULTURE SERVICE OCCUPATIONS. IT WAS DEVELOPED BY A NATIONAL TASK FORCE ON THE BASIS OF RESEARCH FROM STATE STUDIES. SUGGESTIONS FOR…

  2. An exploration of deep level defects in compound semiconductors using optoelectronic modulation spectroscopy

    CERN Document Server

    Chiu, C H

    2001-01-01

    The work is concerned with the detection and characterisation of defect states within semiconductor materials. OptoElectronic Modulation Spectroscopy (OEMS) has been adapted to isolate the electrical and optical responses of traps in semiconductor device and materials. Sub band-gap photons are used to permit penetration into the semiconductor to excite charges in deep defect states. In order to isolate the effect of back-plane charge traps in MESFET structures gate depletion region modulation of the channel current has been eliminated by using a closed loop control system to stabilise the gate depletion capacitance continuously throughout the measurement of the OEMS spectrum. Any change of the channel current will then be due only to the charges within the back-plane interface depletion region between the active layer and buffer/substrate. Depth defined OEMS has also been demonstrated and used to detect defects situated between two preset gate depletion regions. The location of the defect states is therefore ...

  3. Neural mechanisms of infant learning: differences in frontal theta activity during object exploration modulate subsequent object recognition.

    Science.gov (United States)

    Begus, Katarina; Southgate, Victoria; Gliga, Teodora

    2015-05-01

    Investigating learning mechanisms in infancy relies largely on behavioural measures like visual attention, which often fail to predict whether stimuli would be encoded successfully. This study explored EEG activity in the theta frequency band, previously shown to predict successful learning in adults, to directly study infants' cognitive engagement, beyond visual attention. We tested 11-month-old infants (N = 23) and demonstrated that differences in frontal theta-band oscillations, recorded during infants' object exploration, predicted differential subsequent recognition of these objects in a preferential-looking test. Given that theta activity is modulated by motivation to learn in adults, these findings set the ground for future investigation into the drivers of infant learning. PMID:26018832

  4. Exploring Cystic Fibrosis Using Bioinformatics Tools: A Module Designed for the Freshman Biology Course

    Science.gov (United States)

    Zhang, Xiaorong

    2011-01-01

    We incorporated a bioinformatics component into the freshman biology course that allows students to explore cystic fibrosis (CF), a common genetic disorder, using bioinformatics tools and skills. Students learn about CF through searching genetic databases, analyzing genetic sequences, and observing the three-dimensional structures of proteins…

  5. Exploring Ramsey-coherent population trapping atomic clock realized with pulsed microwave modulated laser

    International Nuclear Information System (INIS)

    A scheme for a Ramsey-coherent population trapping (CPT) atomic clock that eliminates the acousto-optic modulator (AOM) is proposed and experimentally studied. Driven by a periodically microwave modulated current, the vertical-cavity surface-emitting laser emits a continuous beam that switches between monochromatic and multichromatic modes. Ramsey-CPT interference has been studied with this mode-switching beam. In eliminating the AOM, which is used to generate pulsed laser in conventional Ramsey-CPT atomic clock, the physics package of the proposed scheme is virtually the same as that of a conventional compact CPT atomic clock, although the resource budget for the electronics will slightly increase as a microwave switch should be added. By evaluating and comparing experimentally recorded signals from the two Ramsey-CPT schemes, the short-term frequency stability of the proposed scheme was found to be 46% better than the scheme with AOM. The experimental results suggest that the implementation of a compact Ramsey-CPT atomic clock promises better frequency stability

  6. Patterns of cis regulatory variation in diverse human populations.

    Directory of Open Access Journals (Sweden)

    Barbara E Stranger

    Full Text Available The genetic basis of gene expression variation has long been studied with the aim to understand the landscape of regulatory variants, but also more recently to assist in the interpretation and elucidation of disease signals. To date, many studies have looked in specific tissues and population-based samples, but there has been limited assessment of the degree of inter-population variability in regulatory variation. We analyzed genome-wide gene expression in lymphoblastoid cell lines from a total of 726 individuals from 8 global populations from the HapMap3 project and correlated gene expression levels with HapMap3 SNPs located in cis to the genes. We describe the influence of ancestry on gene expression levels within and between these diverse human populations and uncover a non-negligible impact on global patterns of gene expression. We further dissect the specific functional pathways differentiated between populations. We also identify 5,691 expression quantitative trait loci (eQTLs after controlling for both non-genetic factors and population admixture and observe that half of the cis-eQTLs are replicated in one or more of the populations. We highlight patterns of eQTL-sharing between populations, which are partially determined by population genetic relatedness, and discover significant sharing of eQTL effects between Asians, European-admixed, and African subpopulations. Specifically, we observe that both the effect size and the direction of effect for eQTLs are highly conserved across populations. We observe an increasing proximity of eQTLs toward the transcription start site as sharing of eQTLs among populations increases, highlighting that variants close to TSS have stronger effects and therefore are more likely to be detected across a wider panel of populations. Together these results offer a unique picture and resource of the degree of differentiation among human populations in functional regulatory variation and provide an estimate for the transferability of complex trait variants across populations.

  7. Deciphering cis-regulatory control in inflammatory cells

    OpenAIRE

    Ghisletti, Serena; Natoli, Gioacchino

    2013-01-01

    In innate immune system cells, such as macrophages and dendritic cells, deployment of inducible gene expression programmes in response to microbes and danger signals requires highly precise regulatory mechanisms. The inflammatory response has to be tailored based on both the triggering stimulus and its dose, and it has to be unfolded in a kinetically complex manner that suits the different phases of the inflammatory process. Genomic characterization of regulatory elements in this context indi...

  8. Computational methods to dissect cis-regulatory transcriptional networks

    Indian Academy of Sciences (India)

    Vibha Rani

    2007-12-01

    The formation of diverse cell types from an invariant set of genes is governed by biochemical and molecular processes that regulate gene activity. A complete understanding of the regulatory mechanisms of gene expression is the major function of genomics. Computational genomics is a rapidly emerging area for deciphering the regulation of metazoan genes as well as interpreting the results of high-throughput screening. The integration of computer science with biology has expedited molecular modelling and processing of large-scale data inputs such as microarrays, analysis of genomes, transcriptomes and proteomes. Many bioinformaticians have developed various algorithms for predicting transcriptional regulatory mechanisms from the sequence, gene expression and interaction data. This review contains compiled information of various computational methods adopted to dissect gene expression pathways.

  9. Exploration of whole brain networks modulated by acupuncture at analgesia acupoint ST36 using scale-specific wavelet correlation analysis

    Institute of Scientific and Technical Information of China (English)

    CHENG Hao; YAN Hao; BAI Li-jun; WANG Bao-guo

    2013-01-01

    Background Previous studies have demonstrated that acupuncture could modulate various brain systems in the resting brain networks.Graph theoretical analysis offers a novel way to investigate the functional organization of the large-scale cortical networks modulated by acupuncture at whole brain level.In this study,we used wavelets correlation analysis to estimate the pairwise correlations between 90 cortical and subcortical human brain regions in normal human volunteers scanned during the post-stimulus resting state.Methods Thirty-two college students,all right-handed and acupuncture na(i)ve,participated in this study.Every participant received only one acupoint stimulation,resulting in 16 subjects in one group.Both structural functional magnetic resonance imaging (fMRI) data (3D sequence with a voxel size of 1 mm3 for anatomical localization) and functional fMRI data (TR=1500 ms,TE=30 ms,flip angle=90°) were collected for each subject.After thresholding the resulting scale-specific wavelet correlation matrices to generate undirected binary graphs,we compared graph metrics of brain organization following verum manual acupuncture (ACU) and sham acupuncture (SHAM) groups.Results The topological parameters of the large-scale brain networks in ACU group were different from those of the SHAM group at multiple scales.There existed distinct modularity functional brain networks during the post-stimulus resting state following ACU and SHAM at multiple scales.Conclusions The distinct modulation patterns of the resting brain attributed to the specific effects evoked by acupuncture.In addition,we also identified that there existed frequency-specific modulation in the post-stimulus resting brain following ACU and SHAM.The modulation may be related to the effects of verum acupuncture on modulating special disorder treatment.This preliminary finding may provide a new clue to understand the relatively functionoriented specificity of acupuncture effects.

  10. Acetylcholine-Based Entropy in Response Selection: A Model of How Striatal Interneurons Modulate Exploration, Exploitation, and Response Variability in Decision Making

    Directory of Open Access Journals (Sweden)

    Andrea eStocco

    2012-02-01

    Full Text Available The basal ganglia play a fundamental role in decision making. Their contribution is typically modeled within a reinforcement learning framework, with the basal ganglia learning to select the options associated with highest value and their dopamine inputs conveying performance feedback. This basic framework, however, does not account for the role of cholinergic interneurons in the striatum, and does not easily explain certain dynamic aspects of decision-making and skill acquisition like the generation of exploratory actions. This paper describes BABE (Basal ganglia Acetylcholine-Based Entropy, a model of the acetylcholine system in the striatum that provides a unified explanation for these phenomena. According to this model, cholinergic interneurons in the striatum control the level of variability in behavior by modulating the number of possible responses that are considered by the basal ganglia, as well as the level of competition between them. This mechanism provides a natural way to account for the role of basal ganglia in generating behavioral variability during the acquisition of certain cognitive skills, as well as for modulating exploration and exploitation in decision making. Compared to a typical reinforcement learning model, BABE showed a greater modulation of response variability in the face of changes in the reward contingencies, allowing for faster learning (and re-learning of option values. Finally, the paper discusses the possible applications of the model to other domains.

  11. Neural mechanisms of infant learning: differences in frontal theta activity during object exploration modulate subsequent object recognition

    OpenAIRE

    Begus, Katarina; Southgate, Victoria; Gliga, Teodora

    2015-01-01

    Investigating learning mechanisms in infancy relies largely on behavioural measures like visual attention, which often fail to predict whether stimuli would be encoded successfully. This study explored EEG activity in the theta frequency band, previously shown to predict successful learning in adults, to directly study infants' cognitive engagement, beyond visual attention. We tested 11-month-old infants (N = 23) and demonstrated that differences in frontal theta-band oscillations, recorded d...

  12. Synthetic and Receptor Signaling Explorations of the Mitragyna Alkaloids: Mitragynine as an Atypical Molecular Framework for Opioid Receptor Modulators.

    Science.gov (United States)

    Kruegel, Andrew C; Gassaway, Madalee M; Kapoor, Abhijeet; Váradi, András; Majumdar, Susruta; Filizola, Marta; Javitch, Jonathan A; Sames, Dalibor

    2016-06-01

    Mu-opioid receptor agonists represent mainstays of pain management. However, the therapeutic use of these agents is associated with serious side effects, including potentially lethal respiratory depression. Accordingly, there is a longstanding interest in the development of new opioid analgesics with improved therapeutic profiles. The alkaloids of the Southeast Asian plant Mitragyna speciosa, represented by the prototypical member mitragynine, are an unusual class of opioid receptor modulators with distinct pharmacological properties. Here we describe the first receptor-level functional characterization of mitragynine and related natural alkaloids at the human mu-, kappa-, and delta-opioid receptors. These results show that mitragynine and the oxidized analogue 7-hydroxymitragynine, are partial agonists of the human mu-opioid receptor and competitive antagonists at the kappa- and delta-opioid receptors. We also show that mitragynine and 7-hydroxymitragynine are G-protein-biased agonists of the mu-opioid receptor, which do not recruit β-arrestin following receptor activation. Therefore, the Mitragyna alkaloid scaffold represents a novel framework for the development of functionally biased opioid modulators, which may exhibit improved therapeutic profiles. Also presented is an enantioselective total synthesis of both (-)-mitragynine and its unnatural enantiomer, (+)-mitragynine, employing a proline-catalyzed Mannich-Michael reaction sequence as the key transformation. Pharmacological evaluation of (+)-mitragynine revealed its much weaker opioid activity. Likewise, the intermediates and chemical transformations developed in the total synthesis allowed the elucidation of previously unexplored structure-activity relationships (SAR) within the Mitragyna scaffold. Molecular docking studies, in combination with the observed chemical SAR, suggest that Mitragyna alkaloids adopt a binding pose at the mu-opioid receptor that is distinct from that of classical opioids. PMID

  13. Hypervelocity Impact of Unstressed and Stressed Titanium in a Whipple Configuration in Support of the Orion Crew Exploration Vehicle Service Module Propellant Tanks

    Science.gov (United States)

    Nahra, Henry K.; Christiansen, Eric; Piekutowski, Andrew; Lyons, Frankel; Keddy, Christopher; Salem, Jonathan; Miller, Joshua; Bohl, William; Poormon, Kevin; Greene, Nathanel; Rodriquez, Karen

    2010-01-01

    Hypervelocity impacts were performed on six unstressed and six stressed titanium coupons with aluminium shielding in order to assess the effects of the partial penetration damage on the post impact micromechanical properties of titanium and on the residual strength after impact. This work is performed in support of the definition of the penetration criteria of the propellant tanks surfaces for the service module of the crew exploration vehicle where such a criterion is based on testing and analyses rather than on historical precedence. The objective of this work is to assess the effects of applied biaxial stress on the damage dynamics and morphology. The crater statistics revealed minute differences between stressed and unstressed coupon damage. The post impact residual stress analyses showed that the titanium strength properties were generally unchanged for the unstressed coupons when compared with undamaged titanium. However, high localized strains were shown near the craters during the tensile tests.

  14. Gene set-based module discovery in the breast cancer transcriptome

    Directory of Open Access Journals (Sweden)

    Zhang Michael Q

    2009-02-01

    Full Text Available Abstract Background Although microarray-based studies have revealed global view of gene expression in cancer cells, we still have little knowledge about regulatory mechanisms underlying the transcriptome. Several computational methods applied to yeast data have recently succeeded in identifying expression modules, which is defined as co-expressed gene sets under common regulatory mechanisms. However, such module discovery methods are not applied cancer transcriptome data. Results In order to decode oncogenic regulatory programs in cancer cells, we developed a novel module discovery method termed EEM by extending a previously reported module discovery method, and applied it to breast cancer expression data. Starting from seed gene sets prepared based on cis-regulatory elements, ChIP-chip data, and gene locus information, EEM identified 10 principal expression modules in breast cancer based on their expression coherence. Moreover, EEM depicted their activity profiles, which predict regulatory programs in each subtypes of breast tumors. For example, our analysis revealed that the expression module regulated by the Polycomb repressive complex 2 (PRC2 is downregulated in triple negative breast cancers, suggesting similarity of transcriptional programs between stem cells and aggressive breast cancer cells. We also found that the activity of the PRC2 expression module is negatively correlated to the expression of EZH2, a component of PRC2 which belongs to the E2F expression module. E2F-driven EZH2 overexpression may be responsible for the repression of the PRC2 expression modules in triple negative tumors. Furthermore, our network analysis predicts regulatory circuits in breast cancer cells. Conclusion These results demonstrate that the gene set-based module discovery approach is a powerful tool to decode regulatory programs in cancer cells.

  15. Conserved non-coding regulatory signatures in Arabidopsis co-expressed gene modules.

    Directory of Open Access Journals (Sweden)

    Jacob B Spangler

    Full Text Available Complex traits and other polygenic processes require coordinated gene expression. Co-expression networks model mRNA co-expression: the product of gene regulatory networks. To identify regulatory mechanisms underlying coordinated gene expression in a tissue-enriched context, ten Arabidopsis thaliana co-expression networks were constructed after manually sorting 4,566 RNA profiling datasets into aerial, flower, leaf, root, rosette, seedling, seed, shoot, whole plant, and global (all samples combined groups. Collectively, the ten networks contained 30% of the measurable genes of Arabidopsis and were circumscribed into 5,491 modules. Modules were scrutinized for cis regulatory mechanisms putatively encoded in conserved non-coding sequences (CNSs previously identified as remnants of a whole genome duplication event. We determined the non-random association of 1,361 unique CNSs to 1,904 co-expression network gene modules. Furthermore, the CNS elements were placed in the context of known gene regulatory networks (GRNs by connecting 250 CNS motifs with known GRN cis elements. Our results provide support for a regulatory role of some CNS elements and suggest the functional consequences of CNS activation of co-expression in specific gene sets dispersed throughout the genome.

  16. Exploration of the Proposition Language Module Theory%语言模块理论的上位命题探略

    Institute of Scientific and Technical Information of China (English)

    奚家文; 李放放; 熊哲宏

    2014-01-01

    作为认知科学中的重要理论,语言模块理论为现今新技术条件下的语言认知机制研究提供了有效进路,其上位命题是“心理(或认知)是模块性的”。文章试图考察该上位命题中隐含的认识论问题,分析了模块理论中功能主义的核心假设,从计算与结构两个角度论证了模块化的认知机制,阐释了模块理论对相对主义这一认识论难题的破解。%Language module theory , as an important theory in cognitive science , provides an effective ap-proach to the study of language cognitive mechanism under current condition of new technologies .The superior proposition is that “psychological ( or cognitive ) is the module .” This paper tries to understand the implied ques-tion of epistemology , analyzes the core assumption of functionalism in module theory , demonstrates the cognitive mechanism of modular from the two aspects of calculation and structure , explains the solution of relativism by mod-ule theory .

  17. Dissection of transcriptional and cis-regulatory control of differentiation in human pancreatic cancer.

    Science.gov (United States)

    Diaferia, Giuseppe R; Balestrieri, Chiara; Prosperini, Elena; Nicoli, Paola; Spaggiari, Paola; Zerbi, Alessandro; Natoli, Gioacchino

    2016-03-15

    The histological grade of carcinomas describes the ability of tumor cells to organize in differentiated epithelial structures and has prognostic and therapeutic impact. Here, we show that differential usage of the genomic repertoire of transcriptional enhancers leads to grade-specific gene expression programs in human pancreatic ductal adenocarcinoma (PDAC). By integrating gene expression profiling, epigenomic footprinting, and loss-of-function experiments in PDAC cell lines of different grade, we identified the repertoires of enhancers specific to high- and low-grade PDACs and the cognate set of transcription factors acting to maintain their activity. Among the candidate regulators of PDAC differentiation, KLF5 was selectively expressed in pre-neoplastic lesions and low-grade primary PDACs and cell lines, where it maintained the acetylation of grade-specific enhancers, the expression of epithelial genes such as keratins and mucins, and the ability to organize glandular epithelia in xenografts. The identification of the transcription factors controlling differentiation in PDACs will help clarify the molecular bases of its heterogeneity and progression. PMID:26769127

  18. Mapping cis-Regulatory Domains in the Human Genome UsingMulti-Species Conservation of Synteny

    Energy Technology Data Exchange (ETDEWEB)

    Ahituv, Nadav; Prabhakar, Shyam; Poulin, Francis; Rubin, EdwardM.; Couronne, Olivier

    2005-06-13

    Our inability to associate distant regulatory elements with the genes that they regulate has largely precluded their examination for sequence alterations contributing to human disease. One major obstacle is the large genomic space surrounding targeted genes in which such elements could potentially reside. In order to delineate gene regulatory boundaries we used whole-genome human-mouse-chicken (HMC) and human-mouse-frog (HMF) multiple alignments to compile conserved blocks of synteny (CBS), under the hypothesis that these blocks have been kept intact throughout evolution at least in part by the requirement of regulatory elements to stay linked to the genes that they regulate. A total of 2,116 and 1,942 CBS>200 kb were assembled for HMC and HMF respectively, encompassing 1.53 and 0.86 Gb of human sequence. To support the existence of complex long-range regulatory domains within these CBS we analyzed the prevalence and distribution of chromosomal aberrations leading to position effects (disruption of a genes regulatory environment), observing a clear bias not only for mapping onto CBS but also for longer CBS size. Our results provide a genome wide data set characterizing the regulatory domains of genes and the conserved regulatory elements within them.

  19. Identification and Characterization of a cis-Regulatory Element for Zygotic Gene Expression in Chlamydomonas reinhardtii.

    Science.gov (United States)

    Hamaji, Takashi; Lopez, David; Pellegrini, Matteo; Umen, James

    2016-01-01

    Upon fertilization Chlamydomonas reinhardtii zygotes undergo a program of differentiation into a diploid zygospore that is accompanied by transcription of hundreds of zygote-specific genes. We identified a distinct sequence motif we term a zygotic response element (ZYRE) that is highly enriched in promoter regions of C reinhardtii early zygotic genes. A luciferase reporter assay was used to show that native ZYRE motifs within the promoter of zygotic gene ZYS3 or intron of zygotic gene DMT4 are necessary for zygotic induction. A synthetic luciferase reporter with a minimal promoter was used to show that ZYRE motifs introduced upstream are sufficient to confer zygotic upregulation, and that ZYRE-controlled zygotic transcription is dependent on the homeodomain transcription factor GSP1. We predict that ZYRE motifs will correspond to binding sites for the homeodomain proteins GSP1-GSM1 that heterodimerize and activate zygotic gene expression in early zygotes. PMID:27172209

  20. RAR/RXR binding dynamics distinguish pluripotency from differentiation associated cis-regulatory elements

    OpenAIRE

    Chatagnon, Amandine; Veber, Philippe; Morin, Valérie; Bedo, Justin; Triqueneaux, Gérard; Sémon, Marie; Laudet, Vincent; D'Alché-Buc, Florence; Benoit, Gérard

    2015-01-01

    In mouse embryonic cells, ligand-activated retinoic acid receptors (RARs) play a key role in inhibiting pluripotency-maintaining genes and activating some major actors of cell differentiation. To investigate the mechanism underlying this dual regulation, we performed joint RAR/RXR ChIP-seq and mRNA-seq time series during the first 48 h of the RA-induced Primitive Endoderm (PrE) differentiation process in F9 embryonal carcinoma (EC) cells. We show here that this dual regulation is associated w...

  1. RAR/RXR binding dynamics distinguish pluripotency from differentiation associated cis-regulatory elements.

    Science.gov (United States)

    Chatagnon, Amandine; Veber, Philippe; Morin, Valérie; Bedo, Justin; Triqueneaux, Gérard; Sémon, Marie; Laudet, Vincent; d'Alché-Buc, Florence; Benoit, Gérard

    2015-05-26

    In mouse embryonic cells, ligand-activated retinoic acid receptors (RARs) play a key role in inhibiting pluripotency-maintaining genes and activating some major actors of cell differentiation. To investigate the mechanism underlying this dual regulation, we performed joint RAR/RXR ChIP-seq and mRNA-seq time series during the first 48 h of the RA-induced Primitive Endoderm (PrE) differentiation process in F9 embryonal carcinoma (EC) cells. We show here that this dual regulation is associated with RAR/RXR genomic redistribution during the differentiation process. In-depth analysis of RAR/RXR binding sites occupancy dynamics and composition show that in undifferentiated cells, RAR/RXR interact with genomic regions characterized by binding of pluripotency-associated factors and high prevalence of the non-canonical DR0-containing RA response element. By contrast, in differentiated cells, RAR/RXR bound regions are enriched in functional Sox17 binding sites and are characterized with a higher frequency of the canonical DR5 motif. Our data offer an unprecedentedly detailed view on the action of RA in triggering pluripotent cell differentiation and demonstrate that RAR/RXR action is mediated via two different sets of regulatory regions tightly associated with cell differentiation status. PMID:25897113

  2. Extensive conservation of ancient microsynteny across metazoans due to cis-regulatory constraints

    OpenAIRE

    Irimia, Manuel; Tena, Juan J.; Alexis, Maria S.; Fernandez-Miñan, Ana; Maeso, Ignacio; Bogdanović, Ozren; de la Calle-Mustienes, Elisa; Roy, Scott W; Gómez-Skarmeta, José L.; Fraser, Hunter B.

    2012-01-01

    The order of genes in eukaryotic genomes has generally been assumed to be neutral, since gene order is largely scrambled over evolutionary time. Only a handful of exceptional examples are known, typically involving deeply conserved clusters of tandemly duplicated genes (e.g., Hox genes and histones). Here we report the first systematic survey of microsynteny conservation across metazoans, utilizing 17 genome sequences. We identified nearly 600 pairs of unrelated genes that have remained tight...

  3. Evolving New Skeletal Traits by cis-Regulatory Changes in Bone Morphogenetic Proteins.

    Science.gov (United States)

    Indjeian, Vahan B; Kingman, Garrett A; Jones, Felicity C; Guenther, Catherine A; Grimwood, Jane; Schmutz, Jeremy; Myers, Richard M; Kingsley, David M

    2016-01-14

    Changes in bone size and shape are defining features of many vertebrates. Here we use genetic crosses and comparative genomics to identify specific regulatory DNA alterations controlling skeletal evolution. Armor bone-size differences in sticklebacks map to a major effect locus overlapping BMP family member GDF6. Freshwater fish express more GDF6 due in part to a transposon insertion, and transgenic overexpression of GDF6 phenocopies evolutionary changes in armor-plate size. The human GDF6 locus also has undergone distinctive regulatory evolution, including complete loss of an enhancer that is otherwise highly conserved between chimps and other mammals. Functional tests show that the ancestral enhancer drives expression in hindlimbs but not forelimbs, in locations that have been specifically modified during the human transition to bipedalism. Both gain and loss of regulatory elements can localize BMP changes to specific anatomical locations, providing a flexible regulatory basis for evolving species-specific changes in skeletal form. PMID:26774823

  4. A cis-Regulatory Mutation of PDSS2 Causes Silky-Feather in Chickens

    OpenAIRE

    Feng, Chungang; Gao, Yu; Dorshorst, Ben; Song, Chi; Gu, Xiaorong; Li, Qingyuan; Li, Jinxiu; Liu, Tongxin; Rubin, Carl-Johan; Zhao, Yiqiang; Wang, Yanqiang; Fei, Jing; Li, Huifang; Chen, Kuanwei; Qu, Hao

    2014-01-01

    Author Summary The feather is an excellent model for evolution and development due to its complex structure and vast diversity. Some chickens have silky-feather because of a loss of hooklets in pennaceous feathers, while most chickens have the wild-type normal feather. Hooklets are formed in the last differentiation stage of the life cycle of a pennaceous feather. Chickens with silky-feather are homozygous for a recessive allele (hookless, h). Silkie chicken from China is one of the breeds sh...

  5. Cis-regulatory mechanisms of left/right asymmetric neuron-subtype specification in C. elegans

    OpenAIRE

    Etchberger, John F.; Eileen B Flowers; Poole, Richard J.; Bashllari, Enkelejda; Hobert, Oliver

    2008-01-01

    Anatomically and functionally defined neuron types are sometimes further classified into individual subtypes based on unique functional or molecular properties. To better understand how developmental programs controlling neuron type specification are mechanistically linked to programs controlling neuronal subtype specification, we have analyzed a neuronal subtype specification program that occurs across the left/right axis in the nervous system of the nematode C. elegans. A terminal selector ...

  6. Exploring binary and ternary modulations on a PA-LCoS device for holographic data storage in a PVA/AA photopolymer

    OpenAIRE

    Martínez Guardiola, Francisco Javier; Fernández Fernández, Roberto; Márquez Ruiz, Andrés; Gallego Rico, Sergi; Álvarez López, Mariela Lázara; Pascual Villalobos, Inmaculada; Beléndez Vázquez, Augusto

    2015-01-01

    We focus on the novelty of three elements in holographic data storage systems (HDSS): the data pager, where we introduce a parallel-aligned liquid crystal on silicon (PA-LCoS) microdisplay; the recording material, where we consider the highly versatile PVA/AA photopolymer; and also in the architecture of the object arm, where a convergent correlator system is introduced. We show that PA-LCoS devices cannot implement pure hybrid-ternary modulated (HTM) data pages but a rather close approximati...

  7. Artificial neural network-based exploration of gene-nutrient interactions in folate and xenobiotic metabolic pathways that modulate susceptibility to breast cancer.

    Science.gov (United States)

    Naushad, Shaik Mohammad; Janaki Ramaiah, M; Pavithrakumari, Manickam; Jayapriya, Jaganathan; Hussain, Tajamul; Alrokayan, Salman A; Gottumukkala, Suryanarayana Raju; Digumarti, Raghunadharao; Kutala, Vijay Kumar

    2016-04-15

    In the current study, an artificial neural network (ANN)-based breast cancer prediction model was developed from the data of folate and xenobiotic pathway genetic polymorphisms along with the nutritional and demographic variables to investigate how micronutrients modulate susceptibility to breast cancer. The developed ANN model explained 94.2% variability in breast cancer prediction. Fixed effect models of folate (400μg/day) and B12 (6μg/day) showed 33.3% and 11.3% risk reduction, respectively. Multifactor dimensionality reduction analysis showed the following interactions in responders to folate: RFC1 G80A×MTHFR C677T (primary), COMT H108L×CYP1A1 m2 (secondary), MTR A2756G (tertiary). The interactions among responders to B12 were RFC1G80A×cSHMT C1420T and CYP1A1 m2×CYP1A1 m4. ANN simulations revealed that increased folate might restore ER and PR expression and reduce the promoter CpG island methylation of extra cellular superoxide dismutase and BRCA1. Dietary intake of folate appears to confer protection against breast cancer through its modulating effects on ER and PR expression and methylation of EC-SOD and BRCA1. PMID:26784656

  8. Power Module

    OpenAIRE

    Gang Fang

    2009-01-01

    Abstract: In this paper, we discuss the upgrade problem of module, and introduce the concepts of the power module, regular power module and uniform power module. We give some results of them. Key words: power group; power module; regular power module; uniform power module

  9. Late Toxicity After Intensity-Modulated Radiation Therapy for Localized Prostate Cancer: An Exploration of Dose–Volume Histogram Parameters to Limit Genitourinary and Gastrointestinal Toxicity

    International Nuclear Information System (INIS)

    Purpose: To characterize the late genitourinary (GU) and gastrointestinal (GI) toxicity for prostate cancer patients treated with intensity-modulated radiation therapy (IMRT) and propose dose–volume histogram (DVH) guidelines to limit late treatment-related toxicity. Methods and Materials: In this study 296 consecutive men were treated with IMRT for adenocarcinoma of the prostate. Most patients received treatment to the prostate with or without proximal seminal vesicles (90%), to a median dose of 76 Gy. Concurrent androgen deprivation therapy was given to 150 men (51%) for a median of 4 months. Late toxicity was defined by Common Toxicity Criteria version 3.0 as greater than 3 months after radiation therapy completion. Four groupings of DVH parameters were defined, based on the percentage of rectal or bladder tissue receiving 70 Gy (V70), 65 Gy (V65), and 40 Gy (V40). These DVH groupings, as well as clinical and treatment characteristics, were correlated to maximal Grade 2+ GU and GI toxicity. Results: With a median follow-up of 41 months, the 4-year freedom from maximal Grade 2+ late toxicity was 81% and 91% for GU and GI systems, respectively, and by last follow-up, the rates of Grade 2+ GU and GI toxicity were 9% and 5%, respectively. On multivariate analysis, whole-pelvic IMRT was associated with Grade 2+ GU toxicity and age was associated with Grade 2+ GI toxicity. Freedom from Grade 2+ GI toxicity at 4 years was 100% for men with rectal V70 ≤10%, V65 ≤20%, and V40 ≤40%; 92% for men with rectal V70 ≤20%, V65 ≤40%, and V40 ≤80%; and 85% for men exceeding these criteria (p = 0.13). These criteria were more highly associated with GI toxicity in men aged ≥70 years (p = 0.07). No bladder dose–volume relationships were associated with the risk of GU toxicity. Conclusions: IMRT is associated with low rates of severe GU or GI toxicity after treatment for prostate cancer. Rectal dose constraints may help limit late GI morbidity.

  10. Groups, rings, modules

    CERN Document Server

    Auslander, Maurice

    2014-01-01

    This classic monograph is geared toward advanced undergraduates and graduate students. The treatment presupposes some familiarity with sets, groups, rings, and vector spaces. The four-part approach begins with examinations of sets and maps, monoids and groups, categories, and rings. The second part explores unique factorization domains, general module theory, semisimple rings and modules, and Artinian rings. Part three's topics include localization and tensor products, principal ideal domains, and applications of fundamental theorem. The fourth and final part covers algebraic field extensions

  11. Abelian modules

    OpenAIRE

    S. Halıcıoğlu; Harmanci, A.; GÜNGÖROĞLU, G.; N. Agayev

    2009-01-01

    In this note, we introduce abelian modules as a generalization of abelian rings. Let R be an arbitrary ring with identity. A module M is called abelian if, for any m Î M and any a Î R, any idempotent e Î R, mae=mea. We prove that every reduced module, every symmetric module, every semicommutative module and every Armendariz module is abelian. For an abelian ring R, we show that the module MR is abelian iff M[x]R[x] is abelian. We produce an example to show that M[x, α] need not be abe...

  12. On Staggered Indecomposable Virasoro Modules

    CERN Document Server

    Kytölä, Kalle

    2009-01-01

    In this article, certain indecomposable Virasoro modules are studied. Specifically, the Virasoro mode L_0 is assumed to be non-diagonalisable, possessing Jordan blocks of rank two. Moreover, the module is further assumed to have a highest weight submodule, the "left module", and that the quotient by this submodule yields another highest weight module, the "right module". Such modules, which have been called staggered, have appeared repeatedly in the logarithmic conformal field theory literature, but their theory has not been explored in full generality. Here, such a theory is developed for the Virasoro algebra using rather elementary techniques. The focus centres on two different but related questions typically encountered in practical studies: How can one identify a given staggered module, and how can one demonstrate the existence of a proposed staggered module. The text is liberally peppered throughout with examples illustrating the general concepts. These have been carefully chosen for their physical relev...

  13. Exploration technology

    Energy Technology Data Exchange (ETDEWEB)

    Roennevik, H.C. [Saga Petroleum A/S, Forus (Norway)

    1996-12-31

    The paper evaluates exploration technology. Topics discussed are: Visions; the subsurface challenge; the creative tension; the exploration process; seismic; geology; organic geochemistry; seismic resolution; integration; drilling; value creation. 4 refs., 22 figs.

  14. GEOPHYSICAL EXPLORATION

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>20101939 Bi Bingkun (No.1 Geological Surveying Party,Henan Bureau of Geology and Mineral Resources Exploration and Development,Luoyang 471023,China) Application of the Electric Method to Bauxite Exploration,Henan Province

  15. Environmental and genetic interactions reveal FLOWERING LOCUS C as a modulator of the natural variation for the plasticity of flowering in Arabidopsis.

    Science.gov (United States)

    Méndez-Vigo, Belén; Savic, Marija; Ausín, Israel; Ramiro, Mercedes; Martín, Beatriz; Picó, F Xavier; Alonso-Blanco, Carlos

    2016-02-01

    The timing of flowering initiation depends strongly on the environment, a property termed as the plasticity of flowering. Such plasticity determines the adaptive potential of plants because it provides phenotypic buffer against environmental changes, and its natural variation contributes to evolutionary adaptation. We addressed the genetic mechanisms of the natural variation for this plasticity in Arabidopsis thaliana by analysing a population of recombinant inbred lines derived from Don-0 and Ler accessions collected from distinct climates. Quantitative trait locus (QTL) mapping in four environmental conditions differing in photoperiod, vernalization treatment and ambient temperature detected the folllowing: (i) FLOWERING LOCUS C (FLC) as a large effect QTL affecting flowering time differentially in all environments; (ii) numerous QTL displaying smaller effects specifically in some conditions; and (iii) significant genetic interactions between FLC and other loci. Hence, the variation for the plasticity of flowering is determined by a combination of environmentally sensitive and specific QTL, and epistasis. Analysis of FLC from Don identified a new and more active allele likely caused by a cis-regulatory deletion covering the non-coding RNA COLDAIR. Further characterization of four FLC natural alleles showed different environmental and genetic interactions. Thus, FLC appears as a major modulator of the natural variation for the plasticity of flowering to multiple environmental factors. PMID:26173848

  16. Efficient Electro-Optical Modulation Based on Indium Tin Oxide

    CERN Document Server

    Shi, Kaifeng

    2015-01-01

    We experimentally demonstrate several electro-optical modulators based on transparent conducting oxides. Our previous work demonstrated the modulator structure on glass substrate with broadband bias polarity-dependent modulation. Further exploration shows similar modulation effect of the modulator on quartz and silicon substrate.

  17. Cis-regulatory control of the nodal gene, initiator of the sea urchin oral ectoderm gene network

    OpenAIRE

    Nam, Jongmin; Su, Yi-Hsien; Lee, Pei Yun; Robertson, Anthony J; Coffman, James A.; Davidson, Eric H.

    2007-01-01

    Expression of the nodal gene initiates the gene regulatory network which establishes the transcriptional specification of the oral ectoderm in the sea urchin embryo. This gene encodes a TGFβ ligand, and in Strongylocentrotus purpuratus its transcription is activated in the presumptive oral ectoderm at about the 30-cell stage. Thereafter Nodal signaling occurs among all cells of the oral ectoderm territory, and nodal expression is required for expression of oral ectoderm regulatory genes. The ...

  18. Tissue-specific expression of the human alpha 1-antitrypsin gene is controlled by multiple cis-regulatory elements.

    OpenAIRE

    Shen, R F; Li, Y.; Sifers, R N; Wang, H.; Hardick, C; Tsai, S. Y.; Woo, S L

    1987-01-01

    Human alpha 1-antitrypsin (AAT) is expressed in the liver, and a 318 bp fragment immediately flanking the CAP site of the gene was found to be sufficient to drive the expression of a reporter gene (CAT) specifically in hepatoma cells. The enhancing activity however, was orientation-dependent. The DNA fragment was separated into a distal region and a proximal region. A "core enhancer" sequence GTGGTTTC is present within the distal region and is capable of activity enhancement in both orientati...

  19. Tissue-specific expression of the human alpha 1-antitrypsin gene is controlled by multiple cis-regulatory elements.

    Science.gov (United States)

    Shen, R F; Li, Y; Sifers, R N; Wang, H; Hardick, C; Tsai, S Y; Woo, S L

    1987-10-26

    Human alpha 1-antitrypsin (AAT) is expressed in the liver, and a 318 bp fragment immediately flanking the CAP site of the gene was found to be sufficient to drive the expression of a reporter gene (CAT) specifically in hepatoma cells. The enhancing activity however, was orientation-dependent. The DNA fragment was separated into a distal region and a proximal region. A "core enhancer" sequence GTGGTTTC is present within the distal region and is capable of activity enhancement in both orientations when complemented by the proximal region in the sense orientation. The results strongly suggest that there are multiple cis-acting elements in the human AAT gene that confer cell specificity for its expression. Nuclear proteins prepared from the hepatoma cells bound specifically to the proximal region in a band-shifting assay that was resistant to competition by the globin promoter DNA. Foot-printing analysis showed a protected domain within the proximal region that contains a nearly perfect palindromic sequence TGGTTAATATTCACCA, which may be important in the regulation of AAT expression in the liver. PMID:2823229

  20. The contribution of cis-regulatory elements to head-to-head gene pairs’ co-expression pattern

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Transcription regulation is one of the most critical pipelines in biological process,in which cis-elements play the role as gene expression regulators.We attempt to deduce the principles underlying the co-expression of "head-to-head" gene pairs by analyzing activities or behaviors of the shared cis-elements.A network component analysis was performed to estimate the impact of cis-elements on gene promoters and their activities under different conditions.Our discoveries reveal how biological system uses those regulatory elements to control the expression pattern of "head-to-head" gene pairs and the whole transcription regulation system.

  1. Identification of Predictive Cis-Regulatory Elements Using a Discriminative Objective Function and a Dynamic Search Space.

    Directory of Open Access Journals (Sweden)

    Rahul Karnik

    Full Text Available The generation of genomic binding or accessibility data from massively parallel sequencing technologies such as ChIP-seq and DNase-seq continues to accelerate. Yet state-of-the-art computational approaches for the identification of DNA binding motifs often yield motifs of weak predictive power. Here we present a novel computational algorithm called MotifSpec, designed to find predictive motifs, in contrast to over-represented sequence elements. The key distinguishing feature of this algorithm is that it uses a dynamic search space and a learned threshold to find discriminative motifs in combination with the modeling of motifs using a full PWM (position weight matrix rather than k-mer words or regular expressions. We demonstrate that our approach finds motifs corresponding to known binding specificities in several mammalian ChIP-seq datasets, and that our PWMs classify the ChIP-seq signals with accuracy comparable to, or marginally better than motifs from the best existing algorithms. In other datasets, our algorithm identifies novel motifs where other methods fail. Finally, we apply this algorithm to detect motifs from expression datasets in C. elegans using a dynamic expression similarity metric rather than fixed expression clusters, and find novel predictive motifs.

  2. In planta analysis of a cis-regulatory cytokinin response motif in Arabidopsis and identification of a novel enhancer sequence.

    Science.gov (United States)

    Ramireddy, Eswarayya; Brenner, Wolfram G; Pfeifer, Andreas; Heyl, Alexander; Schmülling, Thomas

    2013-07-01

    The phytohormone cytokinin plays a key role in regulating plant growth and development, and is involved in numerous physiological responses to environmental changes. The type-B response regulators, which regulate the transcription of cytokinin response genes, are a part of the cytokinin signaling system. Arabidopsis thaliana encodes 11 type-B response regulators (type-B ARRs), and some of them were shown to bind in vitro to the core cytokinin response motif (CRM) 5'-(A/G)GAT(T/C)-3' or, in the case of ARR1, to an extended motif (ECRM), 5'-AAGAT(T/C)TT-3'. Here we obtained in planta proof for the functionality of the latter motif. Promoter deletion analysis of the primary cytokinin response gene ARR6 showed that a combination of two extended motifs within the promoter is required to mediate the full transcriptional activation by ARR1 and other type-B ARRs. CRMs were found to be over-represented in the vicinity of ECRMs in the promoters of cytokinin-regulated genes, suggesting their functional relevance. Moreover, an evolutionarily conserved 27 bp long T-rich region between -220 and -193 bp was identified and shown to be required for the full activation by type-B ARRs and the response to cytokinin. This novel enhancer is not bound by the DNA-binding domain of ARR1, indicating that additional proteins might be involved in mediating the transcriptional cytokinin response. Furthermore, genome-wide expression profiling identified genes, among them ARR16, whose induction by cytokinin depends on both ARR1 and other specific type-B ARRs. This together with the ECRM/CRM sequence clustering indicates cooperative action of different type-B ARRs for the activation of particular target genes. PMID:23620480

  3. Cis-Regulatory Elements Determine Germline Specificity and Expression Level of an Isopentenyltransferase Gene in Sperm Cells of Arabidopsis.

    Science.gov (United States)

    Zhang, Jinghua; Yuan, Tong; Duan, Xiaomeng; Wei, Xiaoping; Shi, Tao; Li, Jia; Russell, Scott D; Gou, Xiaoping

    2016-03-01

    Flowering plant sperm cells transcribe a divergent and complex complement of genes. To examine promoter function, we chose an isopentenyltransferase gene known as PzIPT1. This gene is highly selectively transcribed in one sperm cell morphotype of Plumbago zeylanica, which preferentially fuses with the central cell during fertilization and is thus a founding cell of the primary endosperm. In transgenic Arabidopsis (Arabidopsis thaliana), PzIPT1 promoter displays activity in both sperm cells and upon progressive promoter truncation from the 5'-end results in a progressive decrease in reporter production, consistent with occurrence of multiple enhancer sites. Cytokinin-dependent protein binding motifs are identified in the promoter sequence, which respond with stimulation by cytokinin. Expression of PzIPT1 promoter in sperm cells confers specificity independently of previously reported Germline Restrictive Silencer Factor binding sequence. Instead, a cis-acting regulatory region consisting of two duplicated 6-bp Male Gamete Selective Activation (MGSA) motifs occurs near the site of transcription initiation. Disruption of this sequence-specific site inactivates expression of a GFP reporter gene in sperm cells. Multiple copies of the MGSA motif fused with the minimal CaMV35S promoter elements confer reporter gene expression in sperm cells. Similar duplicated MGSA motifs are also identified from promoter sequences of sperm cell-expressed genes in Arabidopsis, suggesting selective activation is possibly a common mechanism for regulation of gene expression in sperm cells of flowering plants. PMID:26739233

  4. Changes in cis-regulatory elements of a key floral regulator are associated with divergence of inflorescence architectures

    OpenAIRE

    Kusters, E.; Pina, Della, S.; Castel, R; Souer, E.; Koes, R

    2015-01-01

    Higher plant species diverged extensively with regard to the moment (flowering time) and position (inflorescence architecture) at which flowers are formed. This seems largely caused by variation in the expression patterns of conserved genes that specify floral meristem identity (FMI), rather than changes in the encoded proteins. Here, we report a functional comparison of the promoters of homologous FMI genes from Arabidopsis, petunia, tomato and Antirrhinum. Analysis of promoter-reporter cons...

  5. Changes in cis-regulatory elements of a key floral regulator are associated with divergence of inflorescence architectures

    NARCIS (Netherlands)

    E. Kusters; S. Della Pina; R. Castel; E. Souer; R. Koes

    2015-01-01

    Higher plant species diverged extensively with regard to the moment (flowering time) and position (inflorescence architecture) at which flowers are formed. This seems largely caused by variation in the expression patterns of conserved genes that specify floral meristem identity (FMI), rather than ch

  6. A Survey of 6,300 Genomic Fragments for cis-Regulatory Activity in the Imaginal Discs of Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Aurélie Jory

    2012-10-01

    Full Text Available Over 6,000 fragments from the genome of Drosophila melanogaster were analyzed for their ability to drive expression of GAL4 reporter genes in the third-instar larval imaginal discs. About 1,200 reporter genes drove expression in the eye, antenna, leg, wing, haltere, or genital imaginal discs. The patterns ranged from large regions to individual cells. About 75% of the active fragments drove expression in multiple discs; 20% were expressed in ventral, but not dorsal, discs (legs, genital, and antenna, whereas ∼23% were expressed in dorsal but not ventral discs (wing, haltere, and eye. Several patterns, for example, within the leg chordotonal organ, appeared a surprisingly large number of times. Unbiased searches for DNA sequence motifs suggest candidate transcription factors that may regulate enhancers with shared activities. Together, these expression patterns provide a valuable resource to the community and offer a broad overview of how transcriptional regulatory information is distributed in the Drosophila genome.

  7. Instant node package module

    CERN Document Server

    Ali, Juzer

    2013-01-01

    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. A practical exploration of the lifecycle of creating node modules as well as learning all of the top features that npm has to offer.Intended for readers who want to create their first node.js modules. The programming paradigm of JavaScript is not covered so a foundation in these concepts would be beneficial.

  8. Distinct repressing modules on the distal region of the SBP2 promoter contribute to its vascular tissue-specific expression in different vegetative organs.

    Science.gov (United States)

    Freitas, Rejane L; Carvalho, Claudine M; Fietto, Luciano G; Loureiro, Marcelo E; Almeida, Andrea M; Fontes, Elizabeth P B

    2007-11-01

    The Glycine max sucrose binding protein (GmSBP2) promoter directs vascular tissue-specific expression of reporter genes in transgenic tobacco. Here we showed that an SBP2-GFP fusion protein under the control of the GmSBP2 promoter accumulates in the vascular tissues of vegetative organs, which is consistent with the proposed involvement of SBP in sucrose transport-dependent physiological processes. Through gain-of-function experiments we confirmed that the tissue-specific determinants of the SBP2 promoter reside in the distal cis-regulatory domain A, CRD-A (position -2000 to -700) that is organized into a modular configuration to suppress promoter activity in tissues other than vascular tissues. The four analyzed CRD-A sub-modules, designates Frag II (-1785/-1508), Frag III (-1507/-1237), Frag IV (-1236/-971) and Frag V (-970/-700), act independently to alter the constitutive pattern of -92pSBP2-mediated GUS expression in different organs. Frag V fused to -92pSBP2-GUS restored the tissue-specific pattern of the full-length promoter in the shoot apex, but not in other organs. Likewise, Frag IV confined GUS expression to the vascular bundle of leaves, whereas Frag II mediated vascular specific expression in roots. Strong stem expression-repressing elements were located at positions -1485 to -1212, as Frag III limited GUS expression to the inner phloem. We have also mapped a procambium silencer to the consensus sequence CAGTTnCaAccACATTcCT which is located in both distal and proximal upstream modules. Fusion of either repressing element-containing module to the constitutive -92pSBP2 promoter suppresses GUS expression in the elongation zone of roots. Together our results demonstrate the unusual aspect of distal sequences negatively controlling tissue-specificity of a plant promoter. PMID:17710554

  9. TRI Explorer

    Data.gov (United States)

    U.S. Environmental Protection Agency — TRI Explorer provides powerful, flexible, user-friendly access to Toxics Release Inventory (TRI) data to help communities identify facilities and chemical disposal...

  10. PROSPECTING EXPLORATION

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    20152148 Chen Qiang(No.106 Geological Party,Guizhou Bureau of Geology and Mineral Exploration and Development,Zunyi563009,China);Ye Deshu Discussion of Reasonable Exploratory Grid of Sedimentary Bauxite Deposit in Wuzhengdao Area of Guizhou

  11. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20090712 Ge Mingjun(General Institution of Mineral Exploration & Development in Qiqihaer of Heilongjiang Province,Qiqihaer 161006,China) Application of Emulsified Diesel Oil Drilling Fluid in Under-Balanced Drilling(Exploration Engineering(Rock & Soil Drilling and Tunneling),ISSN1672-7428,CN11-5063/TD,34(11),2007,p.43-45,1 illus.,2 tables,4 refs.)

  12. On staggered indecomposable Virasoro modules

    International Nuclear Information System (INIS)

    In this article, certain indecomposable Virasoro modules are studied. Specifically, the Virasoro mode L0 is assumed to be non-diagonalisable, possessing Jordan blocks of rank two. Moreover, the module is further assumed to have a highest weight submodule, the ''left module'', and that the quotient by this submodule yields another highest weight module, the ''right module''. Such modules, which have been called staggered, have appeared repeatedly in the logarithmic conformal field theory literature, but their theory has not been explored in full generality. Here, such a theory is developed for the Virasoro algebra using rather elementary techniques. The focus centres on two different but related questions typically encountered in practical studies: How can one identify a given staggered module, and how can one demonstrate the existence of a proposed staggered module. Given just the values of the highest weights of the left and right modules, themselves subject to simple necessary conditions, invariants are defined which together with the knowledge of the left and right modules uniquely identify a staggered module. The possible values of these invariants form a vector space of dimension zero, one or two, and the structures of the left and right modules limit the isomorphism classes of the corresponding staggered modules to an affine subspace (possibly empty). The number of invariants and affine restrictions is purely determined by the structures of the left and right modules. Moreover, in order to facilitate applications, the expressions for the invariants and restrictions are given by formulae as explicit as possible (they generally rely on expressions for Virasoro singular vectors). Finally, the text is liberally peppered throughout with examples illustrating the general concepts. These have been carefully chosen for their physical relevance or for the novel features they exhibit. (orig.)

  13. On staggered indecomposable Virasoro modules

    Energy Technology Data Exchange (ETDEWEB)

    Kytoelae, Kalle [Geneve Univ. (Switzerland); Ridout, David [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2009-06-15

    In this article, certain indecomposable Virasoro modules are studied. Specifically, the Virasoro mode L0 is assumed to be non-diagonalisable, possessing Jordan blocks of rank two. Moreover, the module is further assumed to have a highest weight submodule, the ''left module'', and that the quotient by this submodule yields another highest weight module, the ''right module''. Such modules, which have been called staggered, have appeared repeatedly in the logarithmic conformal field theory literature, but their theory has not been explored in full generality. Here, such a theory is developed for the Virasoro algebra using rather elementary techniques. The focus centres on two different but related questions typically encountered in practical studies: How can one identify a given staggered module, and how can one demonstrate the existence of a proposed staggered module. Given just the values of the highest weights of the left and right modules, themselves subject to simple necessary conditions, invariants are defined which together with the knowledge of the left and right modules uniquely identify a staggered module. The possible values of these invariants form a vector space of dimension zero, one or two, and the structures of the left and right modules limit the isomorphism classes of the corresponding staggered modules to an affine subspace (possibly empty). The number of invariants and affine restrictions is purely determined by the structures of the left and right modules. Moreover, in order to facilitate applications, the expressions for the invariants and restrictions are given by formulae as explicit as possible (they generally rely on expressions for Virasoro singular vectors). Finally, the text is liberally peppered throughout with examples illustrating the general concepts. These have been carefully chosen for their physical relevance or for the novel features they exhibit. (orig.)

  14. Farside explorer

    DEFF Research Database (Denmark)

    Mimoun, David; Wieczorek, Mark A.; Alkalai, Leon;

    2012-01-01

    the most radio-quiet region of near-Earth space, determine the internal structure and thermal evolution of the Moon, from crust to core, and quantify impact hazards in near-Earth space by the measurement of flashes generated by impact events. The Farside Explorer flight system includes two identical solar......Farside Explorer is a proposed Cosmic Vision medium-size mission to the farside of the Moon consisting of two landers and an instrumented relay satellite. The farside of the Moon is a unique scientific platform in that it is shielded from terrestrial radio-frequency interference, it recorded...... the primary differentiation and evolution of the Moon, it can be continuously monitored from the Earth-Moon L2 Lagrange point, and there is a complete lack of reflected solar illumination from the Earth. Farside Explorer will exploit these properties and make the first radio-astronomy measurements from...

  15. GEOPHYSICAL EXPLORATION

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20091853 An Jinzhen(School of Earth and Space Sciences,Peking University,Beijing 100871,China);Zhou Pinggen Experiments on Exploring and Monitoring Landslip-Mass Using Geoelectric Resistivity Observations(Acta Seismologica Sinica,ISSN0253-3782,CN11-2021/P,30(3),2008,p.254-261,6 illus.,1 table,19 refs.)Key words:resistivity methods,landslidesIn the experiments,a high-density resistivity method is used to explore the electric structure of landslip mass,and a resistivity-changing anisotropy method is used to monitor the orientation and speed of main fracture extending of landslip mass.The results are as follows:1)the exploring experiments have verified a part of creep deformation borderline,the depth and thickness of groundwater horizon,and the property of super strata in the landslip mass investigated formerly,which have proved that the landslip belts contain rich groundwater

  16. PROSPECTING EXPLORATION

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20112102 Chen Yiying(Shijiazhuang University of Economics,Shijiazhuang 050031,China);Li Wenbin Automatic Generation of Complicated Fault in Geological Section(Coal Geology & Exploration,ISSN1001-1986,CN61-1155/P,38(5),2010,p.7-12,8 illus.,13 refs.)Key words:faults,map compilation The researches of this paper are the basic theories and essential techniques of simulating complicated faults,and a series of approaches are proposed.Based on the practical geological exploration,data types are analyzed and database is normalized.The strata recovering technique is

  17. GEOCHEMICAL EXPLORATION

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    20150448Cen Kuang(State Key Laboratory of Geological Processes and Mineral Resources,School of Earth Sciences and Resources,China University of Geosciences,Beijing 100083,China);Liu Xiuli The Application of the Aerosol Geochemical Exploration Method to the Jinwozi Gold Deposit(Geophysical and Geochemical Exploration,ISSN1000-8918,CN11-1906/P,38(1),2014,p.18-22,6illus.,12refs.)Key words:gold ores,geogas methods,Xinjiang The application of the aerosol theory and technology to deep prospecting is the basic problem discussed in this paper.The aerosol theory and technology were applied in the

  18. WebPASS Explorer (HR Personnel Management)

    Data.gov (United States)

    US Agency for International Development — WebPass Explorer (WebPASS Framework): USAID is partnering with DoS in the implementation of their WebPass Post Personnel (PS) Module. WebPassPS does not replace...

  19. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>20131973 Luo Zhili(Chengdu University of Technology,Chengdu 610059,China);Sun Wei Reviews of the Exploration History of Stratigraphic Wells in the Sichuan Basin and Analysis of the Obtained Geological Effects(Natural Gas Industry,ISSN1000-0976,CN51-1179/TE,32(4),2012,p.9-12,1illus.,10)

  20. Exploring Television.

    Science.gov (United States)

    Kuhns, William

    "Exploring Television" is an inquiry/discovery textbook designed to help students to understand, analyze, criticize, evaluate, and judge the experiences they have had in front of the television set. The text consists of three main parts. "The Medium" inquires into the radio-movie origins of television and prompts research into the networks and…

  1. PROSPECTING EXPLORATION

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20090715 Chen Tao(Team 604,Geo-Exploration Bureau of Nonferrous Metals of Jilin Province,Huadian 132400,China);Zhao Tieying Present Utilizing Situation and Protective Planning of Mineral Resources in Huadian County,Jilin Province(Jilin Geology,ISSN1001-2427,CN22-1099/P,27(1),2008,p.96-100,4 refs.)

  2. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    20152094 Cai Xiaowen(No.145 Brigade,Gansu Bureau of Coal Geology,Zhangye734000,China);Chen Xiqing Performance Evaluation and Field Application of GFT AntiCollapse and Drag Reduction Agent(Exploration Engineering,ISSN1672-7428,CN11-

  3. Pregnane and Xenobiotic Receptor gene expression in liver cells is modulated by Ets-1 in synchrony with transcription factors Pax5, LEF-1 and c-jun

    Energy Technology Data Exchange (ETDEWEB)

    Kumari, Sangeeta; Saradhi, Mallampati; Rana, Manjul; Chatterjee, Swagata [Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067 (India); Aumercier, Marc [IRI, CNRS USR 3078, Université de Lille-Nord de France, Parc CNRS de la Haute Borne, 50 Avenue de Halley, BP 70478, 59658 Villeneuve d’Ascq Cedex (France); Mukhopadhyay, Gauranga [Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067 (India); Tyagi, Rakesh K., E-mail: rktyagi@yahoo.com [Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067 (India)

    2015-01-15

    Nuclear receptor PXR is predominantly expressed in liver and intestine. Expression of PXR is observed to be dysregulated in various metabolic disorders indicating its involvement in disease development. However, information available on mechanisms of PXR self-regulation is fragmentary. The present investigation identifies some of the regulatory elements responsible for its tight regulation and low cellular expression. Here, we report that the PXR-promoter is a target for some key transcription factors like PU.1/Ets-1, Pax5, LEF-1 and c-Jun. Interestingly, we observed that PXR-promoter responsiveness to Pax5, LEF-1 and c-Jun, is considerably enhanced by Ets transcription factors (PU.1 and Ets-1). Co-transfection of cells with Ets-1, LEF-1 and c-Jun increased PXR-promoter activity by 5-fold and also induced expression of endogenous human PXR. Site-directed mutagenesis and transfection studies revealed that two Ets binding sites and two of the three LEF binding sites in the PXR-promoter are functional and have a positive effect on PXR transcription. Results suggest that expression of Ets family members, in conjunction with Pax5, LEF-1 and c-Jun, lead to coordinated up-regulation of PXR gene transcription. Insights obtained on the regulation of PXR gene have relevance in offering important cues towards normal functioning as well as development of several metabolic disorders via PXR signaling. - Highlights: • The study identified cis-regulatory elements in the nuclear receptor PXR promoter. • Several trans-acting factors modulating the PXR-promoter have been identified. • PU.1/Ets-1, Pax5, LEF-1, c-Jun, LyF-VI and NF-1 act as modulators of the PXR-promoter. • Ets-1 in conjunction with LEF-1 and c-Jun exhibit 5-fold activation of the PXR-promoter. • Insights into PXR-regulation have relevance in normal and pathological conditions.

  4. Pregnane and Xenobiotic Receptor gene expression in liver cells is modulated by Ets-1 in synchrony with transcription factors Pax5, LEF-1 and c-jun

    International Nuclear Information System (INIS)

    Nuclear receptor PXR is predominantly expressed in liver and intestine. Expression of PXR is observed to be dysregulated in various metabolic disorders indicating its involvement in disease development. However, information available on mechanisms of PXR self-regulation is fragmentary. The present investigation identifies some of the regulatory elements responsible for its tight regulation and low cellular expression. Here, we report that the PXR-promoter is a target for some key transcription factors like PU.1/Ets-1, Pax5, LEF-1 and c-Jun. Interestingly, we observed that PXR-promoter responsiveness to Pax5, LEF-1 and c-Jun, is considerably enhanced by Ets transcription factors (PU.1 and Ets-1). Co-transfection of cells with Ets-1, LEF-1 and c-Jun increased PXR-promoter activity by 5-fold and also induced expression of endogenous human PXR. Site-directed mutagenesis and transfection studies revealed that two Ets binding sites and two of the three LEF binding sites in the PXR-promoter are functional and have a positive effect on PXR transcription. Results suggest that expression of Ets family members, in conjunction with Pax5, LEF-1 and c-Jun, lead to coordinated up-regulation of PXR gene transcription. Insights obtained on the regulation of PXR gene have relevance in offering important cues towards normal functioning as well as development of several metabolic disorders via PXR signaling. - Highlights: • The study identified cis-regulatory elements in the nuclear receptor PXR promoter. • Several trans-acting factors modulating the PXR-promoter have been identified. • PU.1/Ets-1, Pax5, LEF-1, c-Jun, LyF-VI and NF-1 act as modulators of the PXR-promoter. • Ets-1 in conjunction with LEF-1 and c-Jun exhibit 5-fold activation of the PXR-promoter. • Insights into PXR-regulation have relevance in normal and pathological conditions

  5. Exploring quadrangulations

    KAUST Repository

    Peng, Chihan

    2014-01-01

    Here we presented a framework to explore quad mesh topologies. The core of our work is a systematic enumeration algorithm that can generate all possible quadrangular meshes inside a defined boundary with an upper limit of v3-v5 pairs. The algorithm is orders of magnitude more efficient than previous work. The combination of topological enumeration and shape-space exploration demonstrates that mesh topology has a powerful influence on geometry. The Fig. 18. A gallery of different quadrilateral meshes for a Shuriken. The quadrilaterals of the model were colored in a postprocess. Topological variations have distinctive, interesting patterns of mesh lines. © 2014 ACM 0730-0301/2014/01-ART3 15.00.

  6. Virtual exploration

    Energy Technology Data Exchange (ETDEWEB)

    Milwood-Hargrave, M.; Francis, A.M. (Ikon Geoscience, Twickenham, Middlesex (United Kingdom))

    1993-09-01

    With the now commonplace implementation of interactive interpretation workstations, the process of generating a time model for a prospect has been simplified and accelerated. This paper shows that for many structural traps, the critical interpretation steps are in subsequently generating a valid depth model, evaluating the depth structure, and being able to realistically assess confidence limits of the model. The development of a comprehensive velocity model is a key element of any depth conversion. Lateral velocity variations across an area are capable of generating structures where the time interpretation is flat. An example is shown in this paper, and the effect of altering the velocity field and the resulting changes to the structure are described. Forward and inverse modeling are used to show that the structure is more favorable than was first expected from the depth conversion. From this example, the idea of sensitivity testing of a number of simple structures is developed. A fully interactive ray trace modeling system integrated with an interpretation workstation allows different confidence limits to be rapidly tested and evaluated. By extending the model into the third dimension, specific scenarios can be constructed in three-dimension (3-D) and uncertainty limits tested on a complete reservoir. Further than this, the construction of type models in 3-D allows the concept of [open quotes]virtual exploration[close quotes] to be realized, whereby specific exploration concepts can be investigated and tested. The virtual exploration model, and its associated seismic data set, form an ideal educational, planning, and training tool for all levels of geophysicists and geologists.

  7. Space exploration

    CERN Document Server

    90, Sol

    2008-01-01

    Space Exploration, is one book in the Britannica Illustrated Science Library Series that is correlated to the science curriculum in grades 5-8. The Britannica Illustrated Science Library is a visually compelling set that covers earth science, life science, and physical science in 16 volumes.  Created for ages 10 and up, each volume provides an overview on a subject and thoroughly explains it through detailed and powerful graphics-more than 1,000 per volume-that turn complex subjects into information that students can grasp.  Each volume contains a glossary with full definitions for vocabulary

  8. Photonics Explorer Workshop

    Science.gov (United States)

    Prasad, Amrita; Debaes, Nathalie

    2014-07-01

    The Photonics Explorer is an intra-curricular educational kit developed in a European project with a pan-European collaboration of over 35 teachers and science education professors. Unlike conventional educational outreach kits, the Photonics Explorer is specifically designed to integrate seamlessly in school curricula and enhance and complement the teaching and learning of science and optics in the classroom. The kit equips teachers with class sets of experimental components, provided within a supporting didactic framework and is designed for lower and upper secondary students (12-18 years). The kit is provided completely free of charge to teachers in conjunction with teacher training courses. The workshop will provide an overview of the Photonics Explorer intra-curricular kit and give teachers the opportunity to work hands-on with the material and didactic content of two modules, `Light Signals' (lower secondary) and `Diffraction and Interference'(upper secondary). We also aim to receive feedback regarding the content, components and didactic framework from teachers from non- European countries, to understand the relevance of the kit for their teaching and the ability for such a kit to integrate into non-EU curricula.

  9. Geoelectrical exploration

    Science.gov (United States)

    Barseem, Mostafa Said; El Lateef, Talaat Ali Abd; Ezz El Deen, Hosny Mahomud; Abdel Rahman, Abd Allah Al Abaseiry

    2015-12-01

    Sinai development is a goal of successive governments in Egypt. The present study is a geoelectrical exploration to find appropriate solutions of the problems affecting the land of a Research Station in Southeast Al Qantara. This research station is one of the Desert Research Center stations to facilitate the development of desert land for agriculture by introducing applied research. It suffers from some problems which can be summarized in the shortage of irrigation water and water logging. The appropriate solutions of these problems have been delineated by the results of 1D and 2D geoelectrical measurements. Electrical resistivity (ER) revealed the subsurface sedimentary sequences and extension of subsurface layers in the horizontal and vertical directions, especially, the water bearing layer. Additionally it helped to choose the most suitable places to drill productive wells with a good condition.

  10. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20111381 Geng Tao(Xi’an Center of Geological Survey of CGS,Xi’an 710054,China);Liu Kuanhou Application of Accurate Inspection of CQG2000 Quasi-Geoid Model to Regional Gravity Survey in Qinghai-Tibetan Plateau(Northwestern Geology,ISSN1009-6248,CN61-1149/P,43(2),2010,p.1-7,1 illus.,2 tables,4 refs.)Key words:gravity exploration,Global Positioning System,Qinghai-Tibetan Plateau During regional gravity survey,accuracy of orthometric height may affect the accuracy of gravity survey directly.The field test in Qinghai-Tibetan Plateau show that the accuracy of CQG2000 quasi-geoid model can satisfy the accuracy of orthometric height during the 1∶200 000 regional gravity survey.Based on the test,the authors summarize the method how the accuracy of height measurement

  11. Lightweight Trauma Module - LTM

    Science.gov (United States)

    Hatfield, Thomas

    2008-01-01

    Current patient movement items (PMI) supporting the military's Critical Care Air Transport Team (CCATT) mission as well as the Crew Health Care System for space (CHeCS) have significant limitations: size, weight, battery duration, and dated clinical technology. The LTM is a small, 20 lb., system integrating diagnostic and therapeutic clinical capabilities along with onboard data management, communication services and automated care algorithms to meet new Aeromedical Evacuation requirements. The Lightweight Trauma Module is an Impact Instrumentation, Inc. project with strong Industry, DoD, NASA, and Academia partnerships aimed at developing the next generation of smart and rugged critical care tools for hazardous environments ranging from the battlefield to space exploration. The LTM is a combination ventilator/critical care monitor/therapeutic system with integrated automatic control systems. Additional capabilities are provided with small external modules.

  12. Modulation of ultrasound to produce multifrequency radiation force1

    OpenAIRE

    Urban, Matthew W.; Fatemi, Mostafa; Greenleaf, James F.

    2010-01-01

    Dynamic radiation force has been used in several types of applications, and is performed by modulating ultrasound with different methods. By modulating ultrasound, energy can be transmitted to tissue, in this case a dynamic force to elicit a low frequency cyclic displacement to inspect the material properties of the tissue. In this paper, different types of modulation are explored including amplitude modulation (AM), double sideband suppressed carrier amplitude modulation AM, linear frequency...

  13. [Exploring Aeronautics

    Science.gov (United States)

    Robinson, Brandi

    2004-01-01

    This summer I have been working with the N.A.S.A. Project at Cuyahoga Community College (Tri-C) under the title of Exploring Aeronautics Project Leader. The class that I have worked with is comprised of students that will enter the eighth grade in the fall of 2004. The program primarily focuses upon math proficiency and individualized class projects. My duties have encompassed both realms. During the first 2-3 weeks of my internship, I worked at NASA Glenn Research Center (GRC) researching, organizing, and compiling information for weekly Scholastic Challenges and the Super Scholastic Challenge. I was able to complete an overview of Scholastic Challenge and staff responsibilities regarding the competition; a proposal for an interactive learning system, Quizdom; a schedule for challenge equipment, as well as a schedule listing submission deadlines for the staff. Also included in my tasks, during these first 2-3 weeks, were assisting Tammy Allen and Candice Thomas with the student application review and interview processes for student applicants. For the student and parent orientation, I was assigned publications and other varying tasks to complete before the start of the program. Upon the commencement of the program, I changed location from NASA GRC to Tri-C Metro Campus, where student classes for the Cleveland site are held. During the duration of the program, I work with the instructor for the Exploring Aeronautics class, kkkk, assisting in classroom management, daily attendance, curriculum, project building, and other tasks as needed. These tasks include the conducting of the weekly competition, known as Scholastic Challenge. As a Project Leader, I am also responsible for one subject area of the Scholastic Challenge aspect of the N.A.S.A. Project curriculum. Each week I have to prepare a mission that the participants will take home the following Monday and at least 10 questions that will be included in the pool of questions used for the Scholastic Challenge

  14. Exploring Mars

    Science.gov (United States)

    Breuil, Stéphanie

    2016-04-01

    Mars is our neighbour planet and has always fascinated humans as it has been seen as a potential abode for life. Knowledge about Mars is huge and was constructed step by step through numerous missions. It could be difficult to describe these missions, the associated technology, the results, the questions they raise, that's why an activity is proposed, that directly interests students. Their production is presented in the poster. Step 1: The main Mars feature and the first Mars explorations using telescope are presented to students. It should be really interesting to present "Mars Canals" from Percival Lowell as it should also warn students against flawed interpretation. Moreover, this study has raised the big question about extra-terrestrial life on Mars for the first time. Using Google Mars is then a good way to show the huge knowledge we have on the planet and to introduce modern missions. Step 2: Students have to choose and describe one of the Mars mission from ESA and NASA. They should work in pairs. Web sites from ESA and NASA are available and the teacher makes sure the main missions will be studied. Step 3: Students have to collect different pieces of information about the mission - When? Which technology? What were the main results? What type of questions does it raise? They prepare an oral presentation in the form they want (role play, academic presentation, using a poster, PowerPoint). They also have to produce playing cards about the mission that could be put on a timeline. Step 4: As a conclusion, the different cards concerning different missions are mixed. Groups of students receive cards and they have to put them on a timeline as fast as possible. It is also possible to play the game "timeline".

  15. The reconstruction of condition-specific transcriptional modules provides new insights in the evolution of yeast AP-1 proteins.

    Directory of Open Access Journals (Sweden)

    Christel Goudot

    Full Text Available AP-1 proteins are transcription factors (TFs that belong to the basic leucine zipper family, one of the largest families of TFs in eukaryotic cells. Despite high homology between their DNA binding domains, these proteins are able to recognize diverse DNA motifs. In yeasts, these motifs are referred as YRE (Yap Response Element and are either seven (YRE-Overlap or eight (YRE-Adjacent base pair long. It has been proposed that the AP-1 DNA binding motif preference relies on a single change in the amino acid sequence of the yeast AP-1 TFs (an arginine in the YRE-O binding factors being replaced by a lysine in the YRE-A binding Yaps. We developed a computational approach to infer condition-specific transcriptional modules associated to the orthologous AP-1 protein Yap1p, Cgap1p and Cap1p, in three yeast species: the model yeast Saccharomyces cerevisiae and two pathogenic species Candida glabrata and Candida albicans. Exploitation of these modules in terms of predictions of the protein/DNA regulatory interactions changed our vision of AP-1 protein evolution. Cis-regulatory motif analyses revealed the presence of a conserved adenine in 5' position of the canonical YRE sites. While Yap1p, Cgap1p and Cap1p shared a remarkably low number of target genes, an impressive conservation was observed in the YRE sequences identified by Yap1p and Cap1p. In Candida glabrata, we found that Cgap1p, unlike Yap1p and Cap1p, recognizes YRE-O and YRE-A motifs. These findings were supported by structural data available for the transcription factor Pap1p (Schizosaccharomyces pombe. Thus, whereas arginine and lysine substitutions in Cgap1p and Yap1p proteins were reported as responsible for a specific YRE-O or YRE-A preference, our analyses rather suggest that the ancestral yeast AP-1 protein could recognize both YRE-O and YRE-A motifs and that the arginine/lysine exchange is not the only determinant of the specialization of modern Yaps for one motif or another.

  16. Conservation and Evolution of Cis-Regulatory Systems in Ascomycete Fungi

    OpenAIRE

    Gasch Audrey P; Moses Alan M; Chiang Derek Y; Fraser Hunter B; Berardini Mark; Eisen Michael B

    2004-01-01

    Relatively little is known about the mechanisms through which gene expression regulation evolves. To investigate this, we systematically explored the conservation of regulatory networks in fungi by examining the cis-regulatory elements that govern the expression of coregulated genes. We first identified groups of coregulated Saccharomyces cerevisiae genes enriched for genes with known upstream or downstream cis-regulatory sequences. Reasoning that many of these gene groups are coregulated in ...

  17. Q-modules

    OpenAIRE

    Q-modules,

    2009-01-01

    In this paper we characterize Q-modules and almost Q-modules. Next we estblish some equivalent conditions for an almost Q-module to be a Q-module. Using these results, some characterizations are given for Noetherian Q-modules.

  18. Module theory, extending modules and generalizations

    CERN Document Server

    Tercan, Adnan

    2016-01-01

    The main focus of this monograph is to offer a comprehensive presentation of known and new results on various generalizations of CS-modules and CS-rings. Extending (or CS) modules are generalizations of injective (and also semisimple or uniform) modules. While the theory of CS-modules is well documented in monographs and textbooks, results on generalized forms of the CS property as well as dual notions are far less present in the literature. With their work the authors provide a solid background to module theory, accessible to anyone familiar with basic abstract algebra. The focus of the book is on direct sums of CS-modules and classes of modules related to CS-modules, such as relative (injective) ejective modules, (quasi) continuous modules, and lifting modules. In particular, matrix CS-rings are studied and clear proofs of fundamental decomposition results on CS-modules over commutative domains are given, thus complementing existing monographs in this area. Open problems round out the work and establish the...

  19. An optical modulator

    OpenAIRE

    Thévenaz, Luc; Dainesi, Paolo

    2003-01-01

    An optical modulator is arranged to compensate for the thermo-optical modulating effects induced by charge-injection based phase modulators. It comprises first modulator means (3), that receive optical radiation (11, 21), direct it along an optical path, apply a first predetermined optical phase modulation by the injection of free charges into the optical path, and output optical radiation (13, 22) so modulated. Compensator means (4) apply, to optical radiation output from (13, 22), or to be ...

  20. Temporary Suppression of Tinnitus by Modulated Sounds

    OpenAIRE

    Reavis, Kelly M.; Rothholtz, Vanessa S.; Tang, Qing; Carroll, Jeff A.; Djalilian, Hamid; Zeng, Fan-Gang

    2012-01-01

    Despite high prevalence of tinnitus and its impact on quality life, there is no cure for tinnitus at present. Here, we report an effective means to temporarily suppress tinnitus by amplitude- and frequency-modulated tones. We systematically explored the interaction between subjective tinnitus and 17 external sounds in 20 chronic tinnitus sufferers. The external sounds included traditionally used unmodulated stimuli such as pure tones and white noise and dynamically modulated stimuli known to ...

  1. Exploring the Universe.

    Science.gov (United States)

    Aviation/Space, 1982

    1982-01-01

    Highlights National Aeronautics and Space Administration's (NASA) space exploration studies, focusing on Voyager at Saturn, advanced Jupiter exploration, infrared observatory, space telescope, Dynamics Explorers (satellites designed to provide understanding of earth/sun energy relationship), and ozone studies. (JN)

  2. Intensity modulated proton therapy

    OpenAIRE

    Kooy, H. M.; Grassberger, C

    2015-01-01

    Intensity modulated proton therapy (IMPT) implies the electromagnetic spatial control of well-circumscribed “pencil beams” of protons of variable energy and intensity. Proton pencil beams take advantage of the charged-particle Bragg peak—the characteristic peak of dose at the end of range—combined with the modulation of pencil beam variables to create target-local modulations in dose that achieves the dose objectives. IMPT improves on X-ray intensity modulated beams (intensity modulated radio...

  3. Transient heliosheath modulation

    Science.gov (United States)

    Quenby, J. J.; Webber, W. R.

    2015-10-01

    Voyager 1 has explored the solar wind-interstellar medium interaction region between the terminal shock and heliopause, following the intensity distribution of Galactic cosmic ray protons above 200 MeV energy. Before this component reached the expected galactic flux level at 121.7 au from the Sun, four episodes of rapid intensity change occurred with a behaviour similar to that found in Forbush Decreases in the inner Solar system, rather than that expected from a mechanism related to models for the long-term modulation found closer to the Sun. Because the mean solar wind flow is both expected and observed to be perpendicular to the radial direction close to the heliopause, an explanation is suggested in terms of transient radial flows related to possible heliopause boundary flapping. It is necessary that the radial flows are of the order either of the sound speed found for conditions downstream of the terminal shock or of the fluctuations found near the boundary by the Voyager 1 Low Energy Charged Particle detector and that the relevant cosmic ray diffusion perpendicular to the mean field is controlled by `slab' fluctuations accounting for about 20 per cent of the total power in the field variance. However, additional radial drift motion related to possible north to south gradients in the magnetic field may allow the inclusion of some diffusion according to the predictions of a theory based upon the presence of 2D turbulence. The required field gradients may arise due to field variation in the field carried by solar plasma flow deflected away from the solar equatorial plane. Modulation amounting to a total 30 per cent drop in galactic intensity requires explanation by a combination of transient effects.

  4. Integration of Bioinformatics and Synthetic Promoters Leads to the Discovery of Novel Elicitor-Responsive cis-Regulatory Sequences in Arabidopsis1[C][W][OA

    Science.gov (United States)

    Koschmann, Jeannette; Machens, Fabian; Becker, Marlies; Niemeyer, Julia; Schulze, Jutta; Bülow, Lorenz; Stahl, Dietmar J.; Hehl, Reinhard

    2012-01-01

    A combination of bioinformatic tools, high-throughput gene expression profiles, and the use of synthetic promoters is a powerful approach to discover and evaluate novel cis-sequences in response to specific stimuli. With Arabidopsis (Arabidopsis thaliana) microarray data annotated to the PathoPlant database, 732 different queries with a focus on fungal and oomycete pathogens were performed, leading to 510 up-regulated gene groups. Using the binding site estimation suite of tools, BEST, 407 conserved sequence motifs were identified in promoter regions of these coregulated gene sets. Motif similarities were determined with STAMP, classifying the 407 sequence motifs into 37 families. A comparative analysis of these 37 families with the AthaMap, PLACE, and AGRIS databases revealed similarities to known cis-elements but also led to the discovery of cis-sequences not yet implicated in pathogen response. Using a parsley (Petroselinum crispum) protoplast system and a modified reporter gene vector with an internal transformation control, 25 elicitor-responsive cis-sequences from 10 different motif families were identified. Many of the elicitor-responsive cis-sequences also drive reporter gene expression in an Agrobacterium tumefaciens infection assay in Nicotiana benthamiana. This work significantly increases the number of known elicitor-responsive cis-sequences and demonstrates the successful integration of a diverse set of bioinformatic resources combined with synthetic promoter analysis for data mining and functional screening in plant-pathogen interaction. PMID:22744985

  5. Integration of bioinformatics and synthetic promoters leads to the discovery of novel elicitor-responsive cis-regulatory sequences in Arabidopsis.

    Science.gov (United States)

    Koschmann, Jeannette; Machens, Fabian; Becker, Marlies; Niemeyer, Julia; Schulze, Jutta; Bülow, Lorenz; Stahl, Dietmar J; Hehl, Reinhard

    2012-09-01

    A combination of bioinformatic tools, high-throughput gene expression profiles, and the use of synthetic promoters is a powerful approach to discover and evaluate novel cis-sequences in response to specific stimuli. With Arabidopsis (Arabidopsis thaliana) microarray data annotated to the PathoPlant database, 732 different queries with a focus on fungal and oomycete pathogens were performed, leading to 510 up-regulated gene groups. Using the binding site estimation suite of tools, BEST, 407 conserved sequence motifs were identified in promoter regions of these coregulated gene sets. Motif similarities were determined with STAMP, classifying the 407 sequence motifs into 37 families. A comparative analysis of these 37 families with the AthaMap, PLACE, and AGRIS databases revealed similarities to known cis-elements but also led to the discovery of cis-sequences not yet implicated in pathogen response. Using a parsley (Petroselinum crispum) protoplast system and a modified reporter gene vector with an internal transformation control, 25 elicitor-responsive cis-sequences from 10 different motif families were identified. Many of the elicitor-responsive cis-sequences also drive reporter gene expression in an Agrobacterium tumefaciens infection assay in Nicotiana benthamiana. This work significantly increases the number of known elicitor-responsive cis-sequences and demonstrates the successful integration of a diverse set of bioinformatic resources combined with synthetic promoter analysis for data mining and functional screening in plant-pathogen interaction. PMID:22744985

  6. Different cis-Regulatory DNA Elements Mediate Developmental Stage- and Tissue-specific Expression of the Human COL2A1 Gene in Transgenic Mice

    OpenAIRE

    Leung, Keith K.H.; Ng, Ling Jim; Ho, Ken K.Y.; Tam, Patrick P L; Cheah, Kathryn S. E.

    1998-01-01

    Expression of the type II collagen gene (human COL2A1, mouse Col2a1) heralds the differentiation of chondrocytes. It is also expressed in progenitor cells of some nonchondrogenic tissues during embryogenesis. DNA sequences in the 5' flanking region and intron 1 are known to control tissue- specific expression in vitro, but the regulation of COL2A1 expression in vivo is not clearly understood. We have tested the regulatory activity of DNA sequences from COL2A1 on the expression of a lacZ repor...

  7. Theria-specific homeodomain and cis-regulatory element evolution of the Dlx3-4 bigene cluster in 12 different mammalian species.

    Science.gov (United States)

    Sumiyama, Kenta; Miyake, Tsutomu; Grimwood, Jane; Stuart, Andrew; Dickson, Mark; Schmutz, Jeremy; Ruddle, Frank H; Myers, Richard M; Amemiya, Chris T

    2012-12-01

    The mammalian Dlx3 and Dlx4 genes are configured as a bigene cluster, and their respective expression patterns are controlled temporally and spatially by cis-elements that largely reside within the intergenic region of the cluster. Previous work revealed that there are conspicuously conserved elements within the intergenic region of the Dlx3-4 bigene clusters of mouse and human. In this paper we have extended these analyses to include 12 additional mammalian taxa (including a marsupial and a monotreme) in order to better define the nature and molecular evolutionary trends of the coding and non-coding functional elements among morphologically divergent mammals. Dlx3-4 regions were fully sequenced from 12 divergent taxa of interest. We identified three theria-specific amino acid replacements in homeodomain of Dlx4 gene that functions in placenta. Sequence analyses of constrained nucleotide sites in the intergenic non-coding region showed that many of the intergenic conserved elements are highly conserved and have evolved slowly within the mammals. In contrast, a branchial arch/craniofacial enhancer I37-2 exhibited accelerated evolution at the branch between the monotreme and therian common ancestor despite being highly conserved among therian species. Functional analysis of I37-2 in transgenic mice has shown that the equivalent region of the platypus fails to drive transcriptional activity in branchial arches. These observations, taken together with our molecular evolutionary data, suggest that theria-specific episodic changes in the I37-2 element may have contributed to craniofacial innovation at the base of the mammalian lineage. PMID:22951979

  8. Isolation and analysis of MPF2-like MADS-box genes from Physaleae and characterization of their cis-regulatory regions

    OpenAIRE

    Riß, Simone

    2009-01-01

    Species with large inflated lantern-like calyces occur in several genera of the family Solanaceae. In Physalis, this morphological novelty has been termed �Chinese lantern� or �Inflated-Calyx-Syndrome� (ICS). It has been shown that in Physalis floridana the MADS-box transcription factor MPF2 is expressed in floral organs, while expression of its ortholog STMADS16 from Solanum tuberosum is solely restricted to vegetative tissues. Expression of MPF2 in floral organs is not only important for fo...

  9. Opportunities and Challenges for Power Electronics in PV Modules (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, S.; Deline, C.; Wohlgemuth, J.; Marion, B.; Granata, J.

    2011-02-01

    The presentation describes the value of adding DC converters and other power electronics to modules to improve their output even when shading or bad cells would otherwise decrease the module output. The presentation was part of a workshop sponsored by ARPA-E exploring the opportunities for power electronics to support PV applications.

  10. Making Authentic Data Accessible: The Sensing the Environment Inquiry Module

    Science.gov (United States)

    Griffis, Kathy; Thadani, Vandana; Wise, Joe

    2008-01-01

    We report on the development of a middle school life sciences inquiry module, Sensing the Environment. This "data-enriched" inquiry module includes a series of activities exploring the nature of science, photosynthesis, transpiration, and natural selection, which culminates in students' querying authentic environmental data to support a scientific…

  11. Undergraduate Laboratory Experiment Modules for Probing Gold Nanoparticle Interfacial Phenomena

    Science.gov (United States)

    Karunanayake, Akila G.; Gunatilake, Sameera R.; Ameer, Fathima S.; Gadogbe, Manuel; Smith, Laura; Mlsna, Deb; Zhang, Dongmao

    2015-01-01

    Three gold-nanoparticle (AuNP) undergraduate experiment modules that are focused on nanoparticles interfacial phenomena have been developed. Modules 1 and 2 explore the synthesis and characterization of AuNPs of different sizes but with the same total gold mass. These experiments enable students to determine how particle size affects the AuNP…

  12. A Trigonometric Exploration.

    Science.gov (United States)

    DiDomenico, Angelo S.

    1992-01-01

    Gives an example of an open exploration using trigonometric relationships in which the law of cosines can be deduced from the law of sines. Discusses the characteristics and value of the exploration process. (MDH)

  13. Exploration and Mining Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2002-09-01

    This Exploration and Mining Technology Roadmap represents the third roadmap for the Mining Industry of the Future. It is based upon the results of the Exploration and Mining Roadmap Workshop held May 10 ñ 11, 2001.

  14. Exploration cost-cutting

    Energy Technology Data Exchange (ETDEWEB)

    Huttrer, J.

    1996-12-31

    This presentation by Jerry Huttrer, President, Geothermal Management Company, discusses the general state of exploration in the geothermal industry today, and mentions some ways to economize and perhaps save costs of geothermal exploration in the future. He suggests an increased use of satellite imagery in the mapping of geothermal resources and the identification of hot spots. Also, coordinating with oil and gas exploration efforts, the efficiency of the exploration task could be optimized.

  15. A Vigorous Explorer Program

    OpenAIRE

    Elvis, Martin; Beasley, Matthew; Brissenden, Roger; Chakrabarti, Supriya; Cherry, Michael; Devlin, Mark; Edelstein, Jerry; Eisenhardt, Peter; Feldman, Paul; Ford, Holland; Gehrels, Neil; Golub, Leon; Marshall, Herman; Martin, Christopher; Mather, John

    2009-01-01

    Explorers have made breakthroughs in many fields of astrophysics. The science from both these missions contributed to three Nobel Prizes - Giacconi (2002), Mather, and Smoot (2006). Explorers have: marked the definitive beginning of precision cosmology, discovered that short gamma-ray bursts are caused by compact star mergers and have measured metalicity to redshifts z>6. NASA Explorers do cutting-edge science that cannot be done by facility-class instruments. The Explorer program provides a ...

  16. Transient Heliosheath Modulation

    CERN Document Server

    Quenby, J J

    2014-01-01

    Voyager 1 has explored the solar wind-interstellar medium interaction region between the terminal shock and heliopause following the intensity distribution of galactic cosmic ray protons above 200 MeV energy. Before this component reached the galactic level at 121.7 AU, 4 episodes of rapid intensity change occured similar to the Forbush Decreases found near the sun, rather than the expected result of models related to those describing Long Term Modulation in the inner solar system. Because the mean solar wind flow is both expected and observed to be perpendicular to the radial direction close to the heliopause, explanation is given in terms of transient radial flows related to possible heliopause boundary flapping. It is necessary that radial flows are at the sound speed found for conditions downstream of the teminal shock and that the relevant perpendicular cosmic ray diffusion is controlled by 'slab' field fluctuations accounting for 20 percent or less of the total power in field variance. However, addition...

  17. Modulated pressure waves in large elastic tubes.

    Science.gov (United States)

    Mefire Yone, G R; Tabi, C B; Mohamadou, A; Ekobena Fouda, H P; Kofané, T C

    2013-09-01

    Modulational instability is the direct way for the emergence of wave patterns and localized structures in nonlinear systems. We show in this work that it can be explored in the framework of blood flow models. The whole modified Navier-Stokes equations are reduced to a difference-differential amplitude equation. The modulational instability criterion is therefore derived from the latter, and unstable patterns occurrence is discussed on the basis of the nonlinear parameter model of the vessel. It is found that the critical amplitude is an increasing function of α, whereas the region of instability expands. The subsequent modulated pressure waves are obtained through numerical simulations, in agreement with our analytical expectations. Different classes of modulated pressure waves are obtained, and their close relationship with Mayer waves is discussed. PMID:24089964

  18. Primordial Inflation Polarization Explorer: Status and Plans

    Science.gov (United States)

    Kogut, Alan

    2009-01-01

    The Primordial Inflation Polarization Explorer is a balloon-borne instrument to measure the polarization of the cosmic microwave background in order to detect the characteristic signature of gravity waves created during an inflationary epoch in the early universe. PIPER combines cold /I.G K\\ optics, 5120 bolometric detectors, and rapid polarization modulation using VPM grids to achieve both high sensitivity and excellent control of systematic errors. I will discuss the current status and plans for the PIPER instrument.

  19. Modulating lignin in plants

    Science.gov (United States)

    Apuya, Nestor; Bobzin, Steven Craig; Okamuro, Jack; Zhang, Ke

    2013-01-29

    Materials and methods for modulating (e.g., increasing or decreasing) lignin content in plants are disclosed. For example, nucleic acids encoding lignin-modulating polypeptides are disclosed as well as methods for using such nucleic acids to generate transgenic plants having a modulated lignin content.

  20. Polarization modulators for CMBPol

    International Nuclear Information System (INIS)

    We review a number of technologies that are candidates for active polarization modulators for CMBPol. The technologies are appropriate for instruments that use bolometric detectors and include birefringent crystal-based and metal-mesh-based half-wave plates, variable phase polarization modulator, Faraday rotator, and photolithographed modulators. We also give a current account of the status of millimeter-wave orthomode transducers.

  1. Polarization modulators for CMBPol

    Energy Technology Data Exchange (ETDEWEB)

    Ade, P A R; Savini, G [Cardiff University, School of Physics and Astronomy, Queens Buildings, The Parade, Cardiff, CF24 3AA (United Kingdom); Chuss, D T [NASA Goddard Space Flight Center, Code 665, Greenbelt, MD, 20771 (United States); Hanany, S [School of Physics and Astronomy, University of Minnesota/Twin Cities, Minneapolis, MN, 55455 (United States); Haynes, V; Pisano, G [University of Manchester, School of Physics and Astronomy - Alan Turing Building, Upper Brooke street, Manchester, M13 4PL (United Kingdom); Keating, B G [Department of Physics, University of California, San Diego, La Jolla, CA 92093-0424 (United States); Kogut, A [Code 665 Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Ruhl, J E [Physics Department, Case Western Reserve University, Cleveland, OH, 44106 (United States); Wollack, E J [Observational Cosmology Laboratory, NASA/GSFC, Greenbelt, MD 20771 (United States)

    2009-03-01

    We review a number of technologies that are candidates for active polarization modulators for CMBPol. The technologies are appropriate for instruments that use bolometric detectors and include birefringent crystal-based and metal-mesh-based half-wave plates, variable phase polarization modulator, Faraday rotator, and photolithographed modulators. We also give a current account of the status of millimeter-wave orthomode transducers.

  2. Towards a sustainable modular robot system for planetary exploration

    Science.gov (United States)

    Hossain, S. G. M.

    This thesis investigates multiple perspectives of developing an unmanned robotic system suited for planetary terrains. In this case, the unmanned system consists of unit-modular robots. This type of robot has potential to be developed and maintained as a sustainable multi-robot system while located far from direct human intervention. Some characteristics that make this possible are: the cooperation, communication and connectivity among the robot modules, flexibility of individual robot modules, capability of self-healing in the case of a failed module and the ability to generate multiple gaits by means of reconfiguration. To demonstrate the effects of high flexibility of an individual robot module, multiple modules of a four-degree-of-freedom unit-modular robot were developed. The robot was equipped with a novel connector mechanism that made self-healing possible. Also, design strategies included the use of series elastic actuators for better robot-terrain interaction. In addition, various locomotion gaits were generated and explored using the robot modules, which is essential for a modular robot system to achieve robustness and thus successfully navigate and function in a planetary environment. To investigate multi-robot task completion, a biomimetic cooperative load transportation algorithm was developed and simulated. Also, a liquid motion-inspired theory was developed consisting of a large number of robot modules. This can be used to traverse obstacles that inevitably occur in maneuvering over rough terrains such as in a planetary exploration. Keywords: Modular robot, cooperative robots, biomimetics, planetary exploration, sustainability.

  3. CS-Rickart modules

    OpenAIRE

    Abyzov, A. N.; Nhan, T. H. N.

    2014-01-01

    In this paper, we introduce and study the concept of CS-Rickart modules, that is a module analogue of the concept of ACS rings. A ring $R$ is called a right weakly semihereditary ring if every its finitly generated right ideal is of the form $P\\oplus S,$ where $P_R$ is a projective module and $S_R$ is a singular module. We describe the ring $R$ over which $\\mathrm{Mat}_n (R)$ is a right ACS ring for any $n \\in \\mathbb {N}$. We show that every finitely generated projective right $R$-module wil...

  4. Exploration Blueprint: Data Book

    Science.gov (United States)

    Drake, Bret G. (Editor)

    2007-01-01

    The material contained in this report was compiled to capture the work performed by the National Aeronautics and Space Administration's (NASA's) Exploration study team in the late 2002 timeframe. The "Exploration Blueprint Data Book" documents the analyses and findings of the 90-day Agency-wide study conducted from September - November 2002. During the summer of 2002, the NASA Deputy Administrator requested that a study be performed with the following objectives: (1) Develop the rationale for exploration beyond low-Earth orbit (2) Develop roadmaps for how to accomplish the first steps through humans to Mars (3) Develop design reference missions as a basis for the roadmaps 4) Make recommendations on what can be done now to effect this future This planning team, termed the Exploration Blueprint, performed architecture analyses to develop roadmaps for how to accomplish the first steps beyond LEO through the human exploration of Mars. The previous NASA Exploration Team activities laid the foundation and framework for development of NASA's Integrated Space Plan. The reference missions resulting from the analysis performed by the Exploration Blueprint team formed the basis for requirement definition, systems development, technology roadmapping, and risk assessments for future human exploration beyond low-Earth orbit. Emphasis was placed on developing recommendations on what could be done now to effect future exploration activities. The Exploration Blueprint team embraced the "Stepping Stone" approach to exploration where human and robotic activities are conducted through progressive expansion outward beyond low-Earth orbit. Results from this study produced a long-term strategy for exploration with near-term implementation plans, program recommendations, and technology investments. Specific results included the development of a common exploration crew vehicle concept, a unified space nuclear strategy, focused bioastronautics research objectives, and an integrated human

  5. International exploration by independent

    International Nuclear Information System (INIS)

    Recent industry trends indicate that the smaller U.S. independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. Foreign finding costs per barrel usually are accepted to be substantially lower than domestic costs because of the large reserve potential of international plays. To get involved in overseas exploration, however, requires the explorationist to adapt to different cultural, financial, legal, operational, and political conditions. Generally, foreign exploration proceeds at a slower pace than domestic exploration because concessions are granted by a country's government, or are explored in partnership with a national oil company. First, the explorationist must prepare a mid- to long-term strategy, tailored to the goals and the financial capabilities of the company; next, is an ongoing evaluation of quality prospects in various sedimentary basins, and careful planning and conduct of the operations. To successfully explore overseas also requires the presence of a minimum number of explorationists and engineers thoroughly familiar with the various exploratory and operational aspects of foreign work. Ideally, these team members will have had a considerable amount of on-site experience in various countries and climates. Independents best suited for foreign expansion are those who have been financially successful in domestic exploration. When properly approached, foreign exploration is well within the reach of smaller U.S. independents, and presents essentially no greater risk than domestic exploration; however, the reward can be much larger and can catapult the company into the 'big leagues.'

  6. Reduced Multiplication Modules

    Indian Academy of Sciences (India)

    Karim Samei

    2011-05-01

    An -module is called a multiplication module if for each submodule of , = for some ideal of . As defined for a commutative ring , an -module is said to be reduced if the intersection of prime submodules of is zero. The prime spectrum and minimal prime submodules of the reduced module are studied. Essential submodules of are characterized via a topological property. It is shown that the Goldie dimension of is equal to the Souslin number of Spec (). Also a finitely generated module is a Baer module if and only if Spec () is an extremally disconnected space; if and only if it is a -module. It is proved that a prime submodule is minimal in if and only if for each $x\\in N,\\mathrm{Ann}(x)\

  7. Frequency modulation in nuclear magnetometer

    International Nuclear Information System (INIS)

    A version of the frequency-modulation magnetometer based on a particular design of the field-modulation nuclear magnetometer is proposed. Disadvantages of field modulation and advantages of frequency modulation are pointed out

  8. Modulation indices for volumetric modulated arc therapy

    International Nuclear Information System (INIS)

    The aim of this study is to present a modulation index (MI) for volumetric modulated arc therapy (VMAT) based on the speed and acceleration analysis of modulating-parameters such as multi-leaf collimator (MLC) movements, gantry rotation and dose-rate, comprehensively. The performance of the presented MI (MIt) was evaluated with correlation analyses to the pre-treatment quality assurance (QA) results, differences in modulating-parameters between VMAT plans versus dynamic log files, and differences in dose-volumetric parameters between VMAT plans versus reconstructed plans using dynamic log files. For comparison, the same correlation analyses were performed for the previously suggested modulation complexity score (MCSv), leaf travel modulation complexity score (LTMCS) and MI by Li and Xing (MI Li and Xing). In the two-tailed unpaired parameter condition, p values were acquired. The Spearman’s rho (rs) values of MIt, MCSv, LTMCS and MI Li and Xing to the local gamma passing rate with 2%/2 mm criterion were −0.658 (p < 0.001), 0.186 (p = 0.251), 0.312 (p = 0.05) and −0.455 (p = 0.003), respectively. The values of rs to the modulating-parameter (MLC positions) differences were 0.917, −0.635, −0.857 and 0.795, respectively (p < 0.001). For dose-volumetric parameters, MIt showed higher statistically significant correlations than the conventional MIs. The MIt showed good performance for the evaluation of the modulation-degree of VMAT plans. (paper)

  9. The Primordial Inflation Explorer (PIXIE)

    Science.gov (United States)

    Kogut, Alan; Chuss, David T.; Dotson, Jessie; Dwek, Eli; Fixsen, Dale J.; Halpern, Mark; Hinshaw, Gary F.; Meyer, Stephan; Moseley, S. Harvey; Seiffert, Michael D.; Spergel, David N.; Wollack, Edward J.

    2014-01-01

    The Primordial Inflation Explorer is an Explorer-class mission to measure the gravity-wave signature of primordial inflation through its distinctive imprint on the linear polarization of the cosmic microwave background. PIXIE uses an innovative optical design to achieve background-limited sensitivity in 400 spectral channels spanning 2.5 decades in frequency from 30 GHz to 6 THz (1 cm to 50 micron wavelength). Multi-moded non-imaging optics feed a polarizing Fourier Transform Spectrometer to produce a set of interference fringes, proportional to the difference spectrum between orthogonal linear polarizations from the two input beams. Multiple levels of symmetry and signal modulation combine to reduce the instrumental signature and confusion from unpolarized sources to negligible levels. PIXIE will map the full sky in Stokes I, Q, and U parameters with angular resolution 2.6 deg and sensitivity 0.2 µK per 1 deg square pixel. The principal science goal is the detection and characterization of linear polarization from an inflationary epoch in the early universe, with tensor-to-scalar ratio r less than 10(exp -3) at 5 standard deviations. In addition, PIXIE will measure the absolute frequency spectrum to constrain physical processes ranging from inflation to the nature of the first stars to the physical conditions within the interstellar medium of the Galaxy. We describe the PIXIE instrument and mission architecture with an emphasis on the expected level of systematic error suppression.

  10. Geochemical exploration for uranium

    International Nuclear Information System (INIS)

    This Technical Report is designed mainly to introduce the methods and techniques of uranium geochemical exploration to exploration geologists who may not have had experience with geochemical exploration methods in their uranium programmes. The methods presented have been widely used in the uranium exploration industry for more than two decades. The intention has not been to produce an exhaustive, detailed manual, although detailed instructions are given for a field and laboratory data recording scheme and a satisfactory analytical method for the geochemical determination of uranium. Rather, the intention has been to introduce the concepts and methods of uranium exploration geochemistry in sufficient detail to guide the user in their effective use. Readers are advised to consult general references on geochemical exploration to increase their understanding of geochemical techniques for uranium

  11. Visual explorer facilitator's guide

    CERN Document Server

    Palus, Charles J

    2010-01-01

    Grounded in research and practice, the Visual Explorer™ Facilitator's Guide provides a method for supporting collaborative, creative conversations about complex issues through the power of images. The guide is available as a component in the Visual Explorer Facilitator's Letter-sized Set, Visual Explorer Facilitator's Post card-sized Set, Visual Explorer Playing Card-sized Set, and is also available as a stand-alone title for purchase to assist multiple tool users in an organization.

  12. The exploration metaphor

    Science.gov (United States)

    Mcgreevy, Michael W.

    1991-01-01

    NASA's experience in planetary exploration has demonstrated that the desktop workstation is inadequate for many visualization situations. The primary mission displays for the unmanned Surveyor missions to the moon during the mid-1960's, for example, were environmental images assembled on the inside surfaces of spherical shells. Future exploration missions will greatly benefit from advances in digital computer and display technology, but there remain unmet user interface needs. Alternative user interfaces and metaphors are needed for planetary exploration and other interactions with complex spatial environments. These interfaces and metaphors would enable the user to directly explore environments and naturally manipulate objects in those environments. Personal simulators, virtual workstations, and telepresence user interfaces are systems capable of providing this integration of user space and task space. The Exploration Metaphor is a useful concept for guiding the design of user interfaces for virtual environments and telepresence. To apply the Exploration Metaphor is to assert that computing is like exploration, and to support objects, operations, and contexts comparable to those encountered in the exploration of natural environments. The Exploration Metaphor, under development for user interfaces in support of NASA's planetary exploration missions and goals, will also benefit other applications where complex spatial information must be visualized. Visualization methods and systems for planetary exploration are becoming increasingly integrated and interactive as computing technology improves. These advances will benefit from virtual environment and telepresence interface technology. A key development has been the processing of multiple images and other sensor data to create detailed digital models of the planets and moons. Data from images of the Earth, Mars, and Miranda, for example, have been converted into 3D models, and dynamic virtual fly-overs have been

  13. SoOSiM: Operating System and Programming Language Exploration

    OpenAIRE

    Baaij, Christiaan; Kuper, Jan; Schubert, Lutz; Lipari, G; Cucinotta, T

    2012-01-01

    SoOSiM is a simulator developed for the purpose of exploring operating system concepts and operating system modules. The simulator provides a highly abstracted view of a computing system, consisting of computing nodes, and components that are concurrently executed on these nodes. OS modules are subsequently modelled as components that progress as a result of reacting to two types of events: messages from other components, or a system-wide tick event. Using this abstract view, a developer can ...

  14. Scouting's Explorer Program

    Science.gov (United States)

    Claerhout, John M.

    1970-01-01

    This article suggests the relationship which the Explorer program could have with colleges, employers, and the students and employees of the future. Exploring as a process of finding out can help young people find their identity, personally and vocationally, and enable college carrer counselors to expand on a sound foundation of vocational…

  15. Central modulators of human pain: Effects of oxytocin, exam stress, breathing exercises and transcranial magnetic stimulation

    OpenAIRE

    Zunhammer, Matthias

    2014-01-01

    The available means to control human pain are insufficient, novel mechanisms of pain modulation must be explored and understood. This cumulative dissertation comprises four studies, which explored potential means to modulate pain in the central nervous system. An overview on the current understanding of pain, its basic mechanisms, and its known modulators is provided. Study 1 tested if a high intranasal dose of the neuro-hypophyseal hormone oxytocin affected perception and processing of therm...

  16. Directed network modules

    CERN Document Server

    Pálla, G; Farkas, I J; Pollner, P; Vicsek, T; Derenyi, Imre; Farkas, Illes J.; Palla, Gergely; Pollner, Peter; Vicsek, Tamas

    2007-01-01

    A search technique locating network modules, i.e., internally densely connected groups of nodes in directed networks is introduced by extending the Clique Percolation Method originally proposed for undirected networks. After giving a suitable definition for directed modules we investigate their percolation transition in the Erdos-Renyi graph both analytically and numerically. We also analyse four real-world directed networks, including Google's own webpages, an email network, a word association graph and the transcriptional regulatory network of the yeast Saccharomyces cerevisiae. The obtained directed modules are validated by additional information available for the nodes. We find that directed modules of real-world graphs inherently overlap and the investigated networks can be classified into two major groups in terms of the overlaps between the modules. Accordingly, in the word-association network and among Google's webpages the overlaps are likely to contain in-hubs, whereas the modules in the email and t...

  17. Uranium exploration in Ecuador

    International Nuclear Information System (INIS)

    The 600-km segment of the Andean Cordillera in Ecuador includes zones that can be correlated, geologically, with uranium districts elsewhere in the Andes. It is believed that these essentially unexplored zones have the potential for economic uranium mineralization. Exploration activity to date has been limited, although it has involved both geochemical and radiometric techniques to evaluate geological concepts. Minor uranium occurrences (with chemical analyses up to 100 ppm) have been encountered, which provide further incentive to commence large-scale systematic exploration. It is recognized that a very large exploration budget and considerable technical expertise will be required to ensure exploration success. Consequently, participation by groups of proven capability from other countries will be sought for Ecuador's national exploration programme. (author)

  18. A photovoltaic module

    OpenAIRE

    Krebs, Frederik C.; Sommer-Larsen, Peter

    2013-01-01

    The present invention relates to a photovoltaic module comprising a carrier substrate, said carrier substrate carrying a purely printed structure comprising printed positive and negative module terminals, a plurality of printed photovoltaic cell units each comprising one or more printed photovoltaic cells, wherein the plurality of printed photovoltaic cell units are electrically connected in series between the positive and the negative module terminals such that any two neighbouring photovolt...

  19. The ANTARES Optical Module

    OpenAIRE

    the ANTARES Collaboration

    2001-01-01

    The ANTARES collaboration is building a deep sea neutrino telescope in the Mediterranean Sea. This detector will cover a sensitive area of typically 0.1 km-squared and will be equipped with about 1000 optical modules. Each of these optical modules consists of a large area photomultiplier and its associated electronics housed in a pressure resistant glass sphere. The design of the ANTARES optical module, which is a key element of the detector, has been finalized following extensive R & D studi...

  20. Model theory and modules

    CERN Document Server

    Prest, M

    1988-01-01

    In recent years the interplay between model theory and other branches of mathematics has led to many deep and intriguing results. In this, the first book on the topic, the theme is the interplay between model theory and the theory of modules. The book is intended to be a self-contained introduction to the subject and introduces the requisite model theory and module theory as it is needed. Dr Prest develops the basic ideas concerning what can be said about modules using the information which may be expressed in a first-order language. Later chapters discuss stability-theoretic aspects of module

  1. Bracket for photovoltaic modules

    Science.gov (United States)

    Ciasulli, John; Jones, Jason

    2014-06-24

    Brackets for photovoltaic ("PV") modules are described. In one embodiment, a saddle bracket has a mounting surface to support one or more PV modules over a tube, a gusset coupled to the mounting surface, and a mounting feature coupled to the gusset to couple to the tube. The gusset can have a first leg and a second leg extending at an angle relative to the mounting surface. Saddle brackets can be coupled to a torque tube at predetermined locations. PV modules can be coupled to the saddle brackets. The mounting feature can be coupled to the first gusset and configured to stand the one or more PV modules off the tube.

  2. Delphi Accounts Receivable Module

    Data.gov (United States)

    Department of Transportation — Delphi accounts receivable module contains the following data elements, but are not limited to customer information, cash receipts, line of accounting details, bill...

  3. Silicon photonic heater-modulator

    Science.gov (United States)

    Zortman, William A.; Trotter, Douglas Chandler; Watts, Michael R.

    2015-07-14

    Photonic modulators, methods of forming photonic modulators and methods of modulating an input optical signal are provided. A photonic modulator includes a disk resonator having a central axis extending along a thickness direction of the disk resonator. The disk resonator includes a modulator portion and a heater portion. The modulator portion extends in an arc around the central axis. A PN junction of the modulator portion is substantially normal to the central axis.

  4. International exploration by independents

    International Nuclear Information System (INIS)

    Recent industry trends indicate that the smaller US independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. It is usually accepted that foreign finding costs per barrel are substantially lower than domestic because of the large reserve potential of international plays. To get involved overseas requires, however, an adaptation to different cultural, financial, legal, operational, and political conditions. Generally foreign exploration proceeds at a slower pace than domestic because concessions are granted by the government, or are explored in partnership with the national oil company. First, a mid- to long-term strategy, tailored to the goals and the financial capabilities of the company, must be prepared; it must be followed by an ongoing evaluation of quality prospects in various sedimentary basins, and a careful planning and conduct of the operations. To successfully explore overseas also requires the presence on the team of a minimum number of explorationists and engineers thoroughly familiar with the various exploratory and operational aspects of foreign work, having had a considerable amount of onsite experience in various geographical and climatic environments. Independents that are best suited for foreign expansion are those that have been financially successful domestically, and have a good discovery track record. When properly approached foreign exploration is well within the reach of smaller US independents and presents essentially no greater risk than domestic exploration; the reward, however, can be much larger and can catapult the company into the big leagues

  5. A Vigorous Explorer Program

    CERN Document Server

    Elvis, Martin; Brissenden, Roger; Chakrabarti, Supriya; Cherry, Michael; Devlin, Mark; Edelstein, Jerry; Eisenhardt, Peter; Feldman, Paul; Ford, Holland; Gehrels, Neil; Golub, Leon; Marshall, Herman; Martin, Christopher; Mather, John; McCandliss, Stephan; McConnell, Mark; McDowell, Jonathan; Meier, David; Millan, Robyn; Mitchell, John; Moos, Warren; Murray, Steven S; Nousek, John; Oegerle, William; Ramsey, Brian; Green, James; Grindlay, Jonathan; Kaaret, Philip; Kaiser, Mary Elizabeth; Kaltenegger, Lisa; Kasper, Justin; Krolik, Julian; Kruk, Jeffrey W; Latham, David; MacKenty, John; Mainzer, Amanda; Ricker, George; Rinehart, Stephen; Romaine, Suzanne; Scowen, Paul; Silver, Eric; Sonneborn, George; Stern, Daniel; Swain, Mark; Swank, Jean; Traub, Wesley; Weisskopf, Martin; Werner, Michael; Wright, Edward

    2009-01-01

    Explorers have made breakthroughs in many fields of astrophysics. The science from both these missions contributed to three Nobel Prizes - Giacconi (2002), Mather, and Smoot (2006). Explorers have: marked the definitive beginning of precision cosmology, discovered that short gamma-ray bursts are caused by compact star mergers and have measured metalicity to redshifts z>6. NASA Explorers do cutting-edge science that cannot be done by facility-class instruments. The Explorer program provides a rapid response to changing science and technology, to enable cutting-edge science at moderate cost. Explorers also enable innovation, and engage & train scientists, managers and engineers, adding human capital to NASA and the nation. The astrophysics Explorer launch rate now being achieved is 1 per 3 years, and budget projections are in the $150M/year range for the next five years. A newly Vigorous Explorer Program should be created to: 1. Reach the long-stated goal of annual astrophysics launches; 2. Find additional ...

  6. The AMPTE CCE Spacecraft. [Active Magnetospheric Particle Tracer Explorer Charge Composition Explorer

    Science.gov (United States)

    Dassoulas, J.; Peterson, M. R.; Margolies, D. L.

    1985-01-01

    The flight segment of the Active Magnetospheric Particle Tracer Explorers (AMPTE) Program consisted of three separate spacecraft which were launched 'piggyback' into orbit aboard a Delta 3924 launch vehicle, from Cape Canaveral, FL, on August 16, 1984. The three spacecaft are the Charge Composition Explorer (CCE), built for NASA by the Applied Physics Laboratory of the Johns Hopkins University (APL/JHU); the Ion Release Module (IRM), built in the Federal Republic of Germany; and the United Kingdom Subsatellite (UKS), built in the United Kingdom. This paper describes the CCE Spacecraft design, development, and early performance in orbit.

  7. Exploration: A misunderstood business

    International Nuclear Information System (INIS)

    The business of exploration is persistently misunderstand. Why? Misunderstandings persist and even pervade educated, sophisticated, and obviously capable business practitioners and savants of an array of disciplines - finance, economics, and the management sciences. Routine and appropriate assumptions that apply for most businesses invoke nonsense applied to exploration, a unique business. The uniqueness of exploration, unrecognized, sustains the misunderstandings. The authors will not here obliterate these obdurate misunderstandings with some revelation. They show, however, how the misunderstandings naturally arise among those who certainly are not used to being naive

  8. Composite Crew Module (CCM) Permeability Characterization

    Science.gov (United States)

    Kirsch, Michael T.

    2013-01-01

    In January 2007, the NASA Administrator chartered the NASA Engineering and Safety Center (NESC) to form an Agency team to design and build a composite crew module in 18 months in order to gain hands-on experience in anticipation that future exploration systems may be made of composite materials. One of the conclusions from this Composite Crew Module Primary Structure assessment was that there was a lack of understanding regarding the ability for composite pressure shells to contain consumable gases, which posed a technical risk relative to the use of a metallic design. After the completion of the Composite Crew Module test program, the test article was used in a new program to assess the overall leakage/permeability and identify specific features associated with high leak rates. This document contains the outcome of the leakage assessment.

  9. Phase-Modulated Optical Communication Systems

    CERN Document Server

    Ho, Keang-Po

    2005-01-01

    Fiber-optic communication systems have revolutionized our telecommunication infrastructures – currently, almost all telephone land-line, cellular, and internet communications must travel via some form of optical fibers. In these transmission systems, neither the phase nor frequency of the optical signal carries information – only the intensity of the signal is used. To transmit more information in a single optical carrier, the phase of the optical carrier must be explored. As a result, there is renewed interest in phase-modulated optical communications, mainly in direct-detection DPSK signals for long-haul optical communication systems. When optical amplifiers are used to maintain certain signal level among the fiber link, the system is limited by amplifier noises and fiber nonlinearities. Phase-Modulated Optical Communication Systems surveys this newly popular area, covering the following topics: The transmitter and receiver for phase-modulated coherent lightwave systems Method for performance analysis o...

  10. Module Architecture for in Situ Space Laboratories

    Science.gov (United States)

    Sherwood, Brent

    2010-01-01

    The paper analyzes internal outfitting architectures for space exploration laboratory modules. ISS laboratory architecture is examined as a baseline for comparison; applicable insights are derived. Laboratory functional programs are defined for seven planet-surface knowledge domains. Necessary and value-added departures from the ISS architecture standard are defined, and three sectional interior architecture options are assessed for practicality and potential performance. Contemporary guidelines for terrestrial analytical laboratory design are found to be applicable to the in-space functional program. Densepacked racks of system equipment, and high module volume packing ratios, should not be assumed as the default solution for exploration laboratories whose primary activities include un-scriptable investigations and experimentation on the system equipment itself.

  11. The modulation of spatial congruency by object-based attention: analysing the "locus" of the modulation.

    Science.gov (United States)

    Luo, Chunming; Lupiáñez, Juan; Funes, María Jesús; Fu, Xiaolan

    2011-12-01

    Earlier studies have demonstrated that spatial cueing differentially reduces stimulus-stimulus congruency (e.g., spatial Stroop) interference but not stimulus-response congruency (e.g., Simon; e.g., Lupiáñez & Funes, 2005). This spatial cueing modulation over spatial Stroop seems to be entirely attributable to object-based attention (e.g., Luo, Lupiáñez, Funes, & Fu, 2010). In the present study, two experiments were conducted to further explore whether the cueing modulation of spatial Stroop is object based and/or space based and to analyse the "locus" of this modulation. In Experiment 1, we found that the cueing modulation over spatial Stroop is entirely object based, independent of stimulus-response congruency. In Experiment 2, we observed that the modulation of object-based attention over the spatial Stroop only occurred at a short cue-target interval (i.e., stimulus onset asynchrony; SOA), whereas the stimulus-response congruency effect was not modulated either by object-based or by location-based attentional cueing. The overall pattern of results suggests that the spatial cueing modulation over spatial Stroop arises from object-based attention and occurs at the perceptual stage of processing. PMID:21923623

  12. PIPER: Primordial Inflation Polarization Explorer

    Science.gov (United States)

    Lazear, Justin; Ade, P.; Benford, D. J.; Bennett, C. L.; Chuss, D. T.; Dotson, J. L.; Eimer, J.; Fixsen, D. J.; Halpern, M.; Hinderks, J.; Hinshaw, G. F.; Irwin, K.; Jhabvala, C.; Johnson, B.; Kogut, A. J.; Mirel, P.; Moseley, S. H.; Staguhn, J.; Switzer, E.; Tucker, C. E.; Weston, A.; Wollack, E.

    2014-01-01

    The Primordial Inflation Polarization ExploreR (PIPER) is a balloon-borne cosmic microwave background (CMB) polarization experiment searching for large-angular scale B-mode polarization to constrain Inflation in the early universe. The Inflationary Big Bang theory predicts that the epoch of inflation will result in a background of gravitational waves. These gravitational waves imprinted their unique B-mode signature on the CMB polarization, two features of which are a peak at ell ~ 80 and a "bump" below ell ~ 10 in the B-mode angular power spectrum. The ell ~ 80 "recombination" peak is the first peak caused by gravitational waves imprinting tensor (B-mode) perturbations onto the CMB spectrum during recombination. Gravitational waves at larger scales have not yet entered the horizon and may not contribute, and at smaller scales have decayed away by other interactions, giving rise to a peak at horizon scale. The ell ~ 10 "reionization" bump is caused by a similar mechanism as the recombination peak, where gravitational waves imprint B-mode perturbations into the spectrum, now at larger horizon scales. PIPER will target the reionization bump while keeping enough angular resolution to measure the recombination peak, with sensitivity down to tensor-to-scalar ratio r = 0.007. A series of flights alternating between north and south will produce nearly full-sky temperature and polarization maps and measure the low-ell spectra. 5120 transition edge sensor (TES) bolometers each with 20 arcmin beamwidth, distributed into 4 rectangular close-packed arrays maintained at 150 mK will provide small-scale resolution and sensitivity. PIPER consists of two co-aligned telescopes, each with a front-end variable-delay polarization modulator rapidly modulating either the Q or U Stokes parameters to provide polarization sensitivity and mitigate systematic errors. To achieve background-limited sensitivity, the entire instrument is enclosed in an open bucket dewar maintained at 1.5 K. PIPER

  13. The Strip Module

    DEFF Research Database (Denmark)

    Pedersen, Tommy

    1996-01-01

    When the behaviour of a ship in waves is to be predicted it is convenient to have a tool which includes different approaches to the problem.The aim of this project is to develop such a tool named the strip theory module. The strip theory module will consist of submodules dependent on the I-ship c...

  14. The FPAX fastbus module

    International Nuclear Information System (INIS)

    The FPAX is a Fastbus module with 4 independent, 2 slave and 2 master, ports on two segments. It operates as a normal master on either segment or as a Block-Mover on both. The processor board is based on a 68020 microprocessor. A local/network switch allows operation as a host or as a normal module on the Fastbus network

  15. Cosmetology. Computerized Learning Modules.

    Science.gov (United States)

    Finnerty, Kathy, Ed.

    Intended to help reading-limited students meet course objectives, these 11 modules are based on instructional materials in cosmetology that have a higher readability equivalent. Modules cover bacteriology, chemical waving, scalp and hair massage, chemistry, hair shaping, hairstyling, chemical hair relaxing, hair coloring, skin and scalp,…

  16. Arts of urban exploration

    DEFF Research Database (Denmark)

    Pinder, David

    2005-01-01

    This paper addresses ways in which artists and cultural practitioners have recently been using forms of urban exploration as a means of engaging with, and intervening in, cities. It takes its cues from recent events on the streets of New York that involved exploring urban spaces through artistic...... that experimental modes of exploration can play a vital role in the development of critical approaches to the cultural geographies of cities. In particular, discussion centres on the political significance of these spatial practices, drawing out what they have to say about two interconnected themes: ‘rights...... to the city’ and ‘writing the city’. Through addressing recent cases of psychogeographical experimentation in terms of these themes, the paper raises broad questions about artistic practices and urban exploration to introduce this theme issue on ‘Arts of urban exploration’ and to lead into the specific...

  17. Uranium exploration in Australia

    International Nuclear Information System (INIS)

    Australia has more low-cost uranium in deposits than any other country, but finding it is not easy. While the price for uranium has been low, little was found but now exploration is starting to increase.

  18. Birth Control Explorer

    Science.gov (United States)

    ... Relationships STIs Media Facebook Twitter Tumblr Shares · 5 Birth Control Explorer Sort by all methods most effective methods ... 100% effective method of birth control. LEARN MORE IUD An IUD is a T-shaped device that ...

  19. Advanced Exploration Systems Program

    Data.gov (United States)

    National Aeronautics and Space Administration — AES consists of more than 35 projects that target high-priority capabilities needed for human exploration such as crew mobility, deep-space habitation, vehicle...

  20. Academics explore humidity's benefits.

    Science.gov (United States)

    Mortimer, Dave

    2008-11-01

    The effects of humidification on hospital superbugs are being explored by some of the UK's top academics, in what Dave Mortimer, national sales manager for Vapac Humidity Control, explains are the UK's first such studies. PMID:19044148

  1. Brazilian uranium exploration program

    International Nuclear Information System (INIS)

    General information on Brazilian Uranium Exploration Program, are presented. The mineralization processes of uranium depoits are described and the economic power of Brazil uranium reserves is evaluated. (M.C.K.)

  2. Exploring Clinical Overview

    DEFF Research Database (Denmark)

    Fleron, Benedicte

    Clinical overview is explored at four emergency departments (EDs) during the introduction of a new IT system to support hereof. Important aspects of clinical overview are described for the clinical practice and for the further development of the IT system.......Clinical overview is explored at four emergency departments (EDs) during the introduction of a new IT system to support hereof. Important aspects of clinical overview are described for the clinical practice and for the further development of the IT system....

  3. Exploring ambiguous realms

    DEFF Research Database (Denmark)

    Clemensen, Nana

    2016-01-01

    In Hang'ombe Village in rural Zambia, the relative lack of physical boundaries between the activities of family members allow children to observe the actions and discussions of adults on close hand, exposing them to the ambiguities of daily life. Children explore these ambiguities in their intera...... interactions, testing social roles and conventions. This article explores the vigilance and creative agency displayed by Hang'ombe children, in an environment spurring their acquisition of distinct social and discursive skills....

  4. Exploring Vietnam's oil potential

    International Nuclear Information System (INIS)

    A brief review is given of the oil production potential in Vietnam. Since Since 1987, the country has been open to foreign investment in offshore exploration but has suffered from a US embargo on trade and economic ties. Nevertheless some exploration has occurred and twenty production sharing contracts with international oil companies has been signed. To date most of the finds have been non-commercial but optimism remains high. (U.K.)

  5. Modulation gamma resonance spectroscopy

    International Nuclear Information System (INIS)

    Possibility to control dynamic processes in a matter through gamma-resonance modulation by high-frequency external variable fields in excess of inverse lifetimes of the Moessbauer nuclei excited states, that is, within the megahertz frequency range lies in the heart of the modulation gamma-resonance spectroscopy. Through the use of the gamma-resonance process theoretical analysis methods and of the equation solution method for the density matrix with the secondary quantization of gamma-radiation field one attacks the problems dealing with the effect of both variable fields and relaxation on gamma-resonance. One has studied the gamma-radiation ultrasound modulation stages. One points out a peculiar role of the gamma-magnetic resonance effect in modulation gamma resonance spectroscopy formation. One forecasts development of the modulation gamma-resonance spectroscopy into the nonlinear gamma-resonance spectroscopy

  6. Solar energy modulator

    Science.gov (United States)

    Hale, R. R. (Inventor); Mcdougal, A. R.

    1984-01-01

    A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror, therby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening.

  7. DLR’s Antarctic Greenhouse Module Project

    OpenAIRE

    Schubert, Daniel; Poulet, Lucie; Zeidler, Conrad; Zabel, Paul

    2013-01-01

    Humanity’s plans to further explore the solar system requires the development of bio-regenerative life support systems (BLSS), fully incorporated into the habitat infrastructure. A Greenhouse Module (GHM) would contribute to food production, CO2 reduction, O2 production, water recycling and waste management. It is essential to test these GHM technologies in a similar environment to space and with relevant mass flows in order to increase their Technology Readiness Level. The German Aerospa...

  8. Exploration Laboratory Analysis

    Science.gov (United States)

    Krihak, M.; Ronzano, K.; Shaw, T.

    2016-01-01

    The Exploration Laboratory Analysis (ELA) project supports the Exploration Medical Capability (ExMC) risk to minimize or reduce the risk of adverse health outcomes and decrements in performance due to in-flight medical capabilities on human exploration missions. To mitigate this risk, the availability of inflight laboratory analysis instrumentation has been identified as an essential capability for manned exploration missions. Since a single, compact space-ready laboratory analysis capability to perform all exploration clinical measurements is not commercially available, the ELA project objective is to demonstrate the feasibility of emerging operational and analytical capability as a biomedical diagnostics precursor to long duration manned exploration missions. The initial step towards ground and flight demonstrations in fiscal year (FY) 2015 was the down selection of platform technologies for demonstrations in the space environment. The technologies selected included two Small Business Innovation Research (SBIR) performers: DNA Medicine Institutes rHEALTH X and Intelligent Optical Systems later flow assays combined with Holomics smartphone analyzer. The selection of these technologies were based on their compact size, breadth of analytical capability and favorable ability to process fluids in a space environment, among several factors. These two technologies will be advanced to meet ground and flight demonstration success criteria and requirements that will be finalized in FY16. Also, the down selected performers will continue the technology development phase towards meeting prototype deliverables in either late 2016 or 2017.

  9. International exploration by independents

    International Nuclear Information System (INIS)

    Recent industry trends indicate that the smaller U.S. independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. The problems of communications and logistics caused by different cultures and by geographic distances must be carefully evaluated. A mid-term to long-term strategy tailored to the goals and the financial capabilities of the company should be prepared and followed by a careful planning of the operations. This paper addresses some aspects of foreign exploration that should be considered before an independent venture into the foreign field. It also provides some guidelines for conducting successful overseas operations. When properly assessed, foreign exploration is well within the reach of smaller U.S. independents and presents no greater risk than domestic exploration; the rewards, however, can be much larger. Furthermore, the Oil and Gas Journal surveys of the 300 largest U.S. petroleum companies show that companies with a consistent foreign exploration policy have fared better financially during difficult times

  10. Probe for the exploration of deposits

    International Nuclear Information System (INIS)

    The exploration probes work by means of a prompt (n,γ) analysis, activation analysis or X-ray fluorescence analysis. The neutrons or gamma radiation are provided by a californium-252 source or a cobalt-57 source which are placed in the probe. The probe is in the form of a pipe consisting of single modules. Each module contains a part of the whole radiation producing, shielding, detector, detector cooling and detector electronic system. They can be screwed onto one another and can be exchanged for other parts. A melt cryostatat or a compressor is used as cooling device, a germanium-(Li) detector as detector, and bismuth and heavy water as shielding. All measuring process can thus be carried out in situ in a relatively short measuring time. (DG)

  11. Debris Disk Explorer : Exploring Stellar Dust Rings

    Science.gov (United States)

    Roberts, Lewis C.; Bryden, G.; Traub, W. A.; Unwin, S. C.; Trauger, J. T.; Krist, J. E.; Star Halo Team

    2013-01-01

    The Debris Disk Explorer (DDX) is a proposed balloon-borne science investigation of debris disks around nearby stars. Debris disks are analogs of the Asteroid Belt (mainly rocky) and Kuiper Belt (mainly icy) in our Solar System. DDX will measure the size, shape, brightness, and color of a statistically significant sample of disks. These measurements will enable us to probe these fundamental questions: what do debris disks tell us about the evolution of planetary systems; how are debris disks produced; how are debris disks shaped by planets; what materials are debris disks made of; how much dust do debris disks make as they grind down; and how long do debris disks live? The DDX instrument is a 0.7-m diameter ultra-light weight off-axis telescope and an imaging coronagraph on a gondola carried by a stratospheric balloon. Its data product is a set of images of each targeted debris disk in multiple broad visible wavelength bands. DDX will address its science questions by taking high-resolution, multi-wavelength images of the debris disks around tens of nearby stars. Two flights are planned; an overnight test flight within the United States followed by a half-global flight in the Southern Hemisphere. This longer flight is needed to fully explore the set of known debris disks accessible only to DDX. It will achieve a raw contrast of 10^-7, with a processed contrast of 10^-8. No existing telescope can match the DDX contrast and resolution performance. A second objective of DDX is to use the near-space environment to raise the Technology Readiness Level (TRL) internal coronagraphs, deformable mirrors, and wavefront sensing and control, all potentially needed for a future space-based telescope for high-contrast exoplanet imaging, for example the Astrophysics Focused Telescope Asset (AFTA) Design Reference study.

  12. Priorities for Venus Exploration

    Science.gov (United States)

    Glaze, L. S.; Beauchamp, P. M.; Chin, G.; Crisp, D.; Grimm, R. E.; Herrick, R. R.; Johnston, S.; Limaye, S. S.; Smrekar, S. E.; Ocampo, A.; Thompson, T. W.

    2013-12-01

    Venus remains one of the most enigmatic bodies in our Solar System. Important questions remain regarding the origin and evolution of the atmosphere, the history of the surface and interior, and how the surface and atmosphere interact. In a broader context, understanding Venus has implications for understanding the evolution of terrestrial planets in our Solar System as well as for interpreting the growing set of observations of extra-solar planets. The Venus Exploration Analysis Group (VEXAG), established in 2005, is chartered by NASA's Planetary Science Division and reports its findings to the NASA Advisory Council. Open to all interested scientists, VEXAG regularly evaluates Venus exploration goals, scientific objectives, investigations and critical measurement requirements, including especially recommendations in the NRC Decadal Survey and the Solar System Exploration Strategic Roadmap. At the last general meeting in November 2012, VEXAG resolved to update the scientific priorities and strategies for Venus exploration. To achieve this goal, three major tasks were defined for 2013, (1) update the document prioritizing Goals, Objectives and Investigations for Venus Exploration, (2) develop a Roadmap for Venus exploration that is consistent with VEXAG priorities as well as Planetary Decadal Survey priorities, and (3) develop a white paper on technologies for Venus missions. Proposed versions of all three documents were presented at the VEXAG general meeting in November 2013. Here, we present the findings and final versions of all three documents for community comment and feedback. A follow-on Workshop on Venus Exploration Targets is also being planned for the early summer of 2014. The workshop will provide a forum for the Venus science community to discuss approaches for addressing high priority investigations. Participants will be encouraged to present their ideas for specific targets on Venus (interior, surface and atmosphere) as well as to present specific data

  13. Photovoltaic module and interlocked stack of photovoltaic modules

    Science.gov (United States)

    Wares, Brian S.

    2014-09-02

    One embodiment relates to an arrangement of photovoltaic modules configured for transportation. The arrangement includes a plurality of photovoltaic modules, each photovoltaic module including a frame. A plurality of individual male alignment features and a plurality of individual female alignment features are included on each frame. Adjacent photovoltaic modules are interlocked by multiple individual male alignment features on a first module of the adjacent photovoltaic modules fitting into and being surrounded by corresponding individual female alignment features on a second module of the adjacent photovoltaic modules. Other embodiments, features and aspects are also disclosed.

  14. On Modules Whose Singular Subgenerated Modules Are Weakly Injective

    Institute of Scientific and Technical Information of China (English)

    S. Dhompongsa; J. Sanwong; S.Plubtieng; H.Tansee

    2001-01-01

    Rings over which every singular right module is injective (briefly,right SI-rings) were introduced and investigated by Goodearl. Weakly injective modules, as a generalization of injective modules, were introduced by Jain and modules are weakly injective, which we call SwI-rings. This concept is extended to SwI-modules, i.e., modules whose singular subgenerated modules are weakly injective. Several characterizations and properties of SwI-rings and SwI-modules are obtained which generalize some earlier known results on SI-rings and weakly semisimple rings.

  15. EXOMARS Descent Module GNC Performance

    Science.gov (United States)

    Portigliotti, S.; Capuano, M.; Montagna, M.; Martella, P.; Venditto, P.

    2007-08-01

    The ExoMars mission is the first ESA led robotic mission of the Aurora Programme and combines technology development with investigations of major scientific interest. Italy is by far the major contributor to the mission through the strong support of the Italian Space Agency (ASI). ExoMars will search for traces of past and present life, characterize the Mars geochemistry and water distribution, improve the knowledge of the Mars environment and geophysics, and identify possible surface hazards to future human exploration missions. ExoMars will also validate the technology for safe Entry, Descent and Landing (EDL) of a large size Descent Module (DM) carrying a Rover with medium range surface mobility and the access to subsurface. The ExoMars project is presently undergoing its Phase B1 with Thales Alenia Space-Italia as Industrial Prime Contractor. Additionally, as Descent Module responsible, a dedicated simulation tool is under development in Thales Alenia Space-Italia, Turin site, for the end-to-end design and validation / verification of the DM Entry Descent and Landing.

  16. Bioelectric modulation of macrophage polarization

    Science.gov (United States)

    Li, Chunmei; Levin, Michael; Kaplan, David L.

    2016-02-01

    Macrophages play a critical role in regulating wound healing and tissue regeneration by changing their polarization state in response to local microenvironmental stimuli. The native roles of polarized macrophages encompass biomaterials and tissue remodeling needs, yet harnessing or directing the polarization response has been largely absent as a potential strategy to exploit in regenerative medicine to date. Recent data have revealed that specific alteration of cells’ resting potential (Vmem) is a powerful tool to direct proliferation and differentiation in a number of complex tissues, such as limb regeneration, craniofacial patterning and tumorigenesis. In this study, we explored the bioelectric modulation of macrophage polarization by targeting ATP sensitive potassium channels (KATP). Glibenclamide (KATP blocker) and pinacidil (KATP opener) treatment not only affect macrophage polarization, but also influence the phenotype of prepolarized macrophages. Furthermore, modulation of cell membrane electrical properties can fine-tune macrophage plasticity. Glibenclamide decreased the secretion and gene expression of selected M1 markers, while pinacidil augmented M1 markers. More interestingly, glibencalmide promoted macrophage alternative activation by enhancing certain M2 markers during M2 polarization. These findings suggest that control of bioelectric properties of macrophages could offer a promising approach to regulate macrophage phenotype as a useful tool in regenerative medicine.

  17. Intelligent spacecraft module

    Science.gov (United States)

    Oungrinis, Konstantinos-Alketas; Liapi, Marianthi; Kelesidi, Anna; Gargalis, Leonidas; Telo, Marinela; Ntzoufras, Sotiris; Paschidi, Mariana

    2014-12-01

    The paper presents the development of an on-going research project that focuses on a human-centered design approach to habitable spacecraft modules. It focuses on the technical requirements and proposes approaches on how to achieve a spatial arrangement of the interior that addresses sufficiently the functional, physiological and psychosocial needs of the people living and working in such confined spaces that entail long-term environmental threats to human health and performance. Since the research perspective examines the issue from a qualitative point of view, it is based on establishing specific relationships between the built environment and its users, targeting people's bodily and psychological comfort as a measure toward a successful mission. This research has two basic branches, one examining the context of the system's operation and behavior and the other in the direction of identifying, experimenting and formulating the environment that successfully performs according to the desired context. The latter aspect is researched upon the construction of a scaled-model on which we run series of tests to identify the materiality, the geometry and the electronic infrastructure required. Guided by the principles of sensponsive architecture, the ISM research project explores the application of the necessary spatial arrangement and behavior for a user-centered, functional interior where the appropriate intelligent systems are based upon the existing mechanical and chemical support ones featured on space today, and especially on the ISS. The problem is set according to the characteristics presented at the Mars500 project, regarding the living quarters of six crew-members, along with their hygiene, leisure and eating areas. Transformable design techniques introduce spatial economy, adjustable zoning and increased efficiency within the interior, securing at the same time precise spatial orientation and character at any given time. The sensponsive configuration is

  18. Evolution of MPCV Service Module Propulsion and GNC Interface Requirements

    Science.gov (United States)

    Hickman, Heather K.; Dickens, Kevin W.; Madsen, Jennifer M.; Gutkowski, Jeffrey P.; Ierardo, Nicola; Jaeger, Markus; Lux, Johannes; Freundenberger, John L.; Paisley, Jonathan

    2014-01-01

    The Orion Multi-Purpose Crew Vehicle Service Module Propulsion Subsystem provides propulsion for the integrated Crew and Service Module. Updates in the exploration architecture between Constellation and MPCV as well as NASA's partnership with the European Space Agency have resulted in design changes to the SM Propulsion Subsystem and updates to the Propulsion interface requirements with Guidance Navigation and Control. This paper focuses on the Propulsion and GNC interface requirement updates between the Constellation Service Module and the European Service Module and how the requirement updates were driven or supported by architecture updates and the desired use of hardware with heritage to United States and European spacecraft for the Exploration Missions, EM-1 and EM-2.

  19. The ANTARES optical module

    International Nuclear Information System (INIS)

    The ANTARES collaboration is building a deep sea neutrino telescope in the Mediterranean Sea. This detector will cover a sensitive area of typically 0.1 km2 and will be equipped with about 1000 optical modules. Each of these optical modules consists of a large area photomultiplier and its associated electronics housed in a pressure resistant glass sphere. The design of the ANTARES optical module, which is a key element of the detector, has been finalized following extensive R and D studies and is reviewed here in detail

  20. Optical modulator including grapene

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ming; Yin, Xiaobo; Zhang, Xiang

    2016-06-07

    The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.

  1. Functorial Test Modules

    OpenAIRE

    Blickle, Manuel; Stäbler, Axel

    2016-01-01

    In this article we introduce a slight modification of the definition of test modules which is an additive functor $\\tau$ on the category of coherent Cartier modules. We show that in many situations this modification agrees with the usual definition of test modules. Furthermore, we show that for a smooth morphism $f \\colon X \\to Y$ of $F$-finite schemes one has a natural isomorphism $f^! \\circ \\tau \\cong \\tau \\circ f^!$. If $f$ is quasi-finite and of finite type we construct a natural transfor...

  2. Water heater control module

    Science.gov (United States)

    Hammerstrom, Donald J

    2013-11-26

    An advanced electric water heater control system that interfaces with a high temperature cut-off thermostat and an upper regulating thermostat. The system includes a control module that is electrically connected to the high-temperature cut-off thermostat and the upper regulating thermostat. The control module includes a switch to open or close the high-temperature cut-off thermostat and the upper regulating thermostat. The control module further includes circuitry configured to control said switch in response to a signal selected from the group of an autonomous signal, a communicated signal, and combinations thereof.

  3. BepiColombo: Exploring Mercury

    Science.gov (United States)

    Geelen, K.; Novara, M.; Fugger, S.; Benkhoff, J.

    2014-04-01

    BepiColombo is an interdisciplinary mission to explore Mercury, the planet closest to the sun, carried out jointly between the European Space Agency and the Japanese Aerospace Exploration Agency. The mission consists of two orbiters dedicated to the detailed study of the planet and of its magnetosphere, the Mercury Planetary Orbiter (MPO) and the Mercury Magnetospheric Orbiter (MMO). The MPO is ESA's scientific contribution to the mission and comprises 11 science instruments. It is a three-axis-stabilized, nadir-pointing spacecraft which will be placed in a polar orbit with a period of approximately 2.3 hours, a periapsis of 480 km and an apoapsis of 1500 km, providing excellent spatial resolution over the entire planet surface. The interplanetary transfer is performed by an Electric Propulsion Module, which is jettisoned when Mercury is reached. It will set off in July 2016 on a journey to the smallest and least explored terrestrial planet in our Solar System. When it arrives at Mercury in January 2024, it will endure temperatures in excess of 350 °C and gather data during its 1 year nominal mission, with a possible 1-year extension. The difficulty of reaching, surviving and operating in the harsh environment of a planet so close to the sun, makes BepiColombo one of the most challenging planetary projects undertaken by ESA so far. A range of major challenges need to be overcome to enable the mission including the electric propulsion system, development of a new Multi-Layer Insulation able to withstand the high temperatures, an original solar panel design, stringent pointing requirements to be maintained in extreme conditions varying from a solar flux of 10 solar constants to eclipse conditions etc. The scientific payload of both spacecraft will provide the detailed information necessary to understand the origin and evolution of the planet itself and its surrounding environment. The scientific objectives focus on a global characterization of Mercury through the

  4. Marine Mineral Exploration

    DEFF Research Database (Denmark)

    exploration requires knowledge of mineral deposits and models of their formation, of geophysical and geochemical exploration methods, and of data evaluation and interpretation methods. These topics are described in detail by an international group of authors. A short description is also given of marine......The past 20 years have seen extensive marine exploration work by the major industrialized countries. Studies have, in part, been concentrated on Pacific manganese nodule occurrences and on massive sulfides on mid-oceanic ridges. An international jurisdictional framework of the sea-bed mineral...... resources was negotiated by the United Nations Conference on the Law of the Sea (UNCLOS III). A most important outcome of this conference was the establishment of an Exclusive Economic Zone (EEZ) of at least 200 nautical miles for all coastal states and the recognition of a deep-sea regime. Mineral deposits...

  5. Interactive Chemical Reactivity Exploration

    CERN Document Server

    Haag, Moritz P; Bosson, Mael; Redon, Stephane; Reiher, Markus

    2014-01-01

    Elucidating chemical reactivity in complex molecular assemblies of a few hundred atoms is, despite the remarkable progress in quantum chemistry, still a major challenge. Black-box search methods to find intermediates and transition-state structures might fail in such situations because of the high-dimensionality of the potential energy surface. Here, we propose the concept of interactive chemical reactivity exploration to effectively introduce the chemist's intuition into the search process. We employ a haptic pointer device with force-feedback to allow the operator the direct manipulation of structures in three dimensions along with simultaneous perception of the quantum mechanical response upon structure modification as forces. We elaborate on the details of how such an interactive exploration should proceed and which technical difficulties need to be overcome. All reactivity-exploration concepts developed for this purpose have been implemented in the Samson programming environment.

  6. Exploring Responses to Xenophobia: Using Workshopping as Critical Pedagogy

    Science.gov (United States)

    Singh, L.; Francis, D.

    2010-01-01

    Our article arises out of our involvement in an undergraduate module (Drama Education 310) at UKZN Faculty of Education, where we used workshop theatre to explore how students construct knowledge and develop socio-cultural understandings of critical events in society such as Xenophobia. The project reflects how young black students constitute…

  7. Exploring general gauge mediation

    International Nuclear Information System (INIS)

    We explore various aspects of General Gauge Mediation (GGM). We present a reformulation of the correlation functions used in GGM, and further elucidate their IR and UV properties. Additionally we clarify the issue of UV sensitivity in the calculation of the soft masses in the MSSM, highlighting the role of the supertrace over the messenger spectrum. Finally, we present weakly coupled messenger models which fully cover the parameter space of GGM. These examples demonstrate that the full parameter space of GGM is physical and realizable. Thus it should be considered a valid basis for future phenomenological explorations of gauge mediation.

  8. Exploring the solar system

    CERN Document Server

    Bond, Peter

    2012-01-01

    The exploration of our solar system is one of humanity's greatest scientific achievements. The last fifty years in particular have seen huge steps forward in our understanding of the planets, the sun, and other objects in the solar system. Whilst planetary science is now a mature discipline - involving geoscientists, astronomers, physicists, and others - many profound mysteries remain, and there is indeed still the tantalizing possibility that we may find evidence of life on another planet in our system.Drawing upon the latest results from the second golden age of Solar System exploration, aut

  9. Exploring Opponent Formats

    DEFF Research Database (Denmark)

    Jensen, Mads Møller; Rasmussen, Majken; Grønbæk, Kaj

    2013-01-01

    The recent growth in development and research in computer-supported physical games has sprouted a wide variety of games merging qualities from both computer games and sports. Despite the increasing interest in this type of games, exploration of their specific game mechanics and the understanding ...... football-training platform, as well as games designed to explore the different opponent formats. The games are qualitatively evaluated to illuminate the qualities of and distinctions between different types of opponent formats, proposed by the framework terminology....

  10. Robotics for Human Exploration

    Science.gov (United States)

    Fong, Terrence; Deans, Mathew; Bualat, Maria

    2013-01-01

    Robots can do a variety of work to increase the productivity of human explorers. Robots can perform tasks that are tedious, highly repetitive or long-duration. Robots can perform precursor tasks, such as reconnaissance, which help prepare for future human activity. Robots can work in support of astronauts, assisting or performing tasks in parallel. Robots can also perform "follow-up" work, completing tasks designated or started by humans. In this paper, we summarize the development and testing of robots designed to improve future human exploration of space.

  11. GREET Pretreatment Module

    Energy Technology Data Exchange (ETDEWEB)

    Adom, Felix K.; Dunn, Jennifer B.; Han, Jeongwoo

    2014-09-01

    A wide range of biofuels and biochemicals can be produced from biomass via different pretreatment technologies that yield sugars. This report documents the material and energy flows that occur when fermentable sugars from four lignocellulosic feedstocks (corn stover, miscanthus, switchgrass, and poplar) are produced via dilute acid pretreatment and ammonia fiber expansion. These flows are documented for inclusion in the pretreatment module of the Greenhouses Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. Process simulations of each pretreatment technology were developed in Aspen Plus. Material and energy consumption data from Aspen Plus were then compiled in the GREET pretreatment module. The module estimates the cradle-to-gate fossil energy consumption (FEC) and greenhouse gas (GHG) emissions associated with producing fermentable sugars. This report documents the data and methodology used to develop this module and the cradle-to-gate FEC and GHG emissions that result from producing fermentable sugars.

  12. A photovoltaic module

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to a photovoltaic module comprising a carrier substrate, said carrier substrate carrying a purely printed structure comprising printed positive and negative module terminals, a plurality of printed photovoltaic cell units each comprising one or more printed...... photovoltaic cells, wherein the plurality of printed photovoltaic cell units are electrically connected in series between the positive and the negative module terminals such that any two neighbouring photovoltaic cell units are electrically connected by a printed interconnecting electrical conductor. The...... carrier substrate comprises a foil and the total thickness of the photovoltaic module is below 500 [mu]m. Moreover, the nominal voltage level between the positive and the negative terminals is at least 5 kV DC....

  13. Ultrasound Modulated Bioluminescence Tomography

    CERN Document Server

    Bal, Guillaume

    2013-01-01

    We propose a method to reconstruct the density of a luminescent source in a highly-scattering medium from ultrasound modulated optical measurements. Our approach is based on the solution to a hybrid inverse source problem for the diffusion equation.

  14. Isothermal Containment Module

    Science.gov (United States)

    1999-01-01

    Isothermal Containment Modules are the temperature-controlling carrier that BioServe built to carry Commercial Generic Bioprocessing Apparatus (CGBA) and in the future, Space Automated Bioproduct Lab (SABL) to the International Space Station.

  15. Electrical modulation of emissivity

    OpenAIRE

    Vassant, Simon; Moldovan Doyen, Ioana Cristina; Marquier, François; Pardo, F.; Gennser, Ulf; Cavanna, Antonella; Pelouard, Jean-Luc; Greffet, Jean-Jacques

    2013-01-01

    We demonstrate that it is possible to modulate the thermal emission through an electrical modulation of the emissivity. The basic idea is to design a device where absorption is due to a resonant phenomenon. If the resonance can be electrically controlled, then absorption and, therefore, thermal emission can be controlled. We demonstrate this general concept using THz resonant absorption by surface phonon polaritons coupled through a gold grating. In our device, absorption is mostly due to a s...

  16. Renewal, Modulation and Superstatistics

    OpenAIRE

    Allegrini, Paolo; Barbi, Francesco; Grigolini, Paolo; Paradisi, Paolo

    2005-01-01

    We consider two different proposals to generate a time series with the same non-Poisson distribution of waiting times, to which we refer to as renewal and modulation. We show that, in spite of the apparent statistical equivalence, the two time series generate different physical effects. Renewal generates aging and anomalous scaling, while modulation yields no aging and either ordinary or anomalous diffusion, according to the prescription used for its generation. We argue, in fact, that the ph...

  17. Directed network modules

    Science.gov (United States)

    Palla, Gergely; Farkas, Illés J.; Pollner, Péter; Derényi, Imre; Vicsek, Tamás

    2007-06-01

    A search technique locating network modules, i.e. internally densely connected groups of nodes in directed networks is introduced by extending the clique percolation method originally proposed for undirected networks. After giving a suitable definition for directed modules we investigate their percolation transition in the Erdos Rényi graph both analytically and numerically. We also analyse four real-world directed networks, including Google's own web-pages, an email network, a word association graph and the transcriptional regulatory network of the yeast Saccharomyces cerevisiae. The obtained directed modules are validated by additional information available for the nodes. We find that directed modules of real-world graphs inherently overlap and the investigated networks can be classified into two major groups in terms of the overlaps between the modules. Accordingly, in the word-association network and Google's web-pages, overlaps are likely to contain in-hubs, whereas the modules in the email and transcriptional regulatory network tend to overlap via out-hubs.

  18. Second generation SLAC modulator

    International Nuclear Information System (INIS)

    The Stanford Linear Accelerator Laboratory has undertaken the construction of a single pass electron-positron collider. In order to reach required beam energy 235 new klystrons needed upgraded modulator systems. The collider will use 50 GeV electrons and positrons. The increase in accelerator energy from the present 30 GeV necessitates the replacement of existing 35 MW klystrons with new 67 MW units. The doubling of klystron output power required a redesign of the modulator system. The 67 MW klystron needs a 350 kV beam voltage pulse with a 3.7 μs pulse width. A new pulse transformer was designed to deliver the increased voltage and pulse width. Pulse cable design was evaluated to obtain increased reliability of that critical element. The modulator, with the exception of its power supply, was rebuilt to produce the required power increase while enhancing reliability and improving maintainability. An investigation of present thyratron switch tube performance under the new operating conditions resulted in agitation and some warranted panic but these conditions were mitigated after several successful experiments and some evolutionary narrowing of the klystron pulse width. The discussion will cover the upgraded modulator system specifications and some details of the new pulse transformer tank, pulse cable, modulator, and modulator switch tube

  19. Directed network modules

    International Nuclear Information System (INIS)

    A search technique locating network modules, i.e. internally densely connected groups of nodes in directed networks is introduced by extending the clique percolation method originally proposed for undirected networks. After giving a suitable definition for directed modules we investigate their percolation transition in the Erdos-Renyi graph both analytically and numerically. We also analyse four real-world directed networks, including Google's own web-pages, an email network, a word association graph and the transcriptional regulatory network of the yeast Saccharomyces cerevisiae. The obtained directed modules are validated by additional information available for the nodes. We find that directed modules of real-world graphs inherently overlap and the investigated networks can be classified into two major groups in terms of the overlaps between the modules. Accordingly, in the word-association network and Google's web-pages, overlaps are likely to contain in-hubs, whereas the modules in the email and transcriptional regulatory network tend to overlap via out-hubs

  20. Second generation SLAC modulator

    Energy Technology Data Exchange (ETDEWEB)

    Donaldson, A.R.; Cron, J.C.; Hanselman, R.R.

    1986-06-01

    The Stanford Linear Accelerator Laboratory has undertaken the construction of a single pass electron-positron collider. In order to reach required beam energy 235 new klystrons needed upgraded modulator systems. The collider will use 50 GeV electrons and positrons. The increase in accelerator energy from the present 30 GeV necessitates the replacement of existing 35 MW klystrons with new 67 MW units. The doubling of klystron output power required a redesign of the modulator system. The 67 MW klystron needs a 350 kV beam voltage pulse with a 3.7 ..mu..s pulse width. A new pulse transformer was designed to deliver the increased voltage and pulse width. Pulse cable design was evaluated to obtain increased reliability of that critical element. The modulator, with the exception of its power supply, was rebuilt to produce the required power increase while enhancing reliability and improving maintainability. An investigation of present thyratron switch tube performance under the new operating conditions resulted in agitation and some warranted panic but these conditions were mitigated after several successful experiments and some evolutionary narrowing of the klystron pulse width. The discussion will cover the upgraded modulator system specifications and some details of the new pulse transformer tank, pulse cable, modulator, and modulator switch tube.

  1. Photovoltaic module reliability workshop

    Energy Technology Data Exchange (ETDEWEB)

    Mrig, L. (ed.)

    1990-01-01

    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986--1990. The reliability Photo Voltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warranties available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the US, PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  2. Photovoltaic module reliability workshop

    Science.gov (United States)

    Mrig, L.

    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986 to 1990. The reliability photovoltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warrantees available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the U.S., PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  3. Directed network modules

    Energy Technology Data Exchange (ETDEWEB)

    Palla, Gergely [Statistical and Biological Physics Research Group of HAS, Pazmany Peter Setany 1A, Budapest, H-1117 (Hungary); Farkas, Illes J [Statistical and Biological Physics Research Group of HAS, Pazmany Peter Setany 1A, Budapest, H-1117 (Hungary); Pollner, Peter [Statistical and Biological Physics Research Group of HAS, Pazmany Peter Setany 1A, Budapest, H-1117 (Hungary); Derenyi, Imre [Department of Biological Physics, Eoetvoes University, Pazmany Peter Setany 1A, Budapest, H-1117 (Hungary); Vicsek, Tamas [Statistical and Biological Physics Research Group of HAS, Pazmany Peter Setany 1A, Budapest, H-1117 (Hungary)

    2007-06-15

    A search technique locating network modules, i.e. internally densely connected groups of nodes in directed networks is introduced by extending the clique percolation method originally proposed for undirected networks. After giving a suitable definition for directed modules we investigate their percolation transition in the Erdos-Renyi graph both analytically and numerically. We also analyse four real-world directed networks, including Google's own web-pages, an email network, a word association graph and the transcriptional regulatory network of the yeast Saccharomyces cerevisiae. The obtained directed modules are validated by additional information available for the nodes. We find that directed modules of real-world graphs inherently overlap and the investigated networks can be classified into two major groups in terms of the overlaps between the modules. Accordingly, in the word-association network and Google's web-pages, overlaps are likely to contain in-hubs, whereas the modules in the email and transcriptional regulatory network tend to overlap via out-hubs.

  4. Geophysics in uranium exploration

    International Nuclear Information System (INIS)

    There are no revolutionary new methods of uranium exploration on the horizon. Continuing improvements in existing methods and types of instrumentation are to be expected, but the main scope of improvement will hinge upon using the best of the available methods more meticulously and systematically, and paying more attention to the analysis of data. (author)

  5. SpaceExplorer

    DEFF Research Database (Denmark)

    Hansen, Thomas Riisgaard

    2007-01-01

    Web pages are designed to be displayed on a single screen, but as more and more screens are being introduced in our surroundings a burning question becomes how to design, interact, and display web pages on multiple devices and displays. In this paper I present the SpaceExplorer prototype, which...

  6. Exploring Racism through Photography

    Science.gov (United States)

    Fey, Cass; Shin, Ryan; Cinquemani, Shana; Marino, Catherine

    2010-01-01

    Photography is a powerful medium with which to explore social issues and concerns through the intersection of artistic form and concept. Through the discussions of images and suggested activities, students will understand various ways photographers have documented and addressed racism and discrimination. This Instructional Resource presents a…

  7. Exploring Opponent Formats

    DEFF Research Database (Denmark)

    Jensen, Mads Møller; Rasmussen, Majken; Grønbæk, Kaj

    2013-01-01

    The recent growth in development and research in computer-supported physical games has sprouted a wide variety of games merging qualities from both computer games and sports. Despite the increasing interest in this type of games, exploration of their specific game mechanics and the understanding ...

  8. The design explorer project

    DEFF Research Database (Denmark)

    Pejtersen, Annelise Mark; Sonnenwald, Diane H.; Buur, Jacob;

    1997-01-01

    It is widely recognized that the increasingly dynamic and competitive business environment requires the exploration and integration of specialized knowledge from different domains in order to create innovative and competitive artefacts and reduce design and development costs. This paper presents ...... industries, manufacturing, hospitals and libraries....

  9. Exploring the Educational Future

    Science.gov (United States)

    Merritt, Elizabeth E.

    2012-01-01

    Futures studies uses scenarios--stories of the future--to explore how trends and events shaping our world may play out in future decades. This article features a short scenario set in California in 2037, depicting twelve-year-old Moya and her brother mart, whose "fenced community" has opted for a system of self-directed, online learning to educate…

  10. Exploring Careers. Office Occupations.

    Science.gov (United States)

    Bureau of Labor Statistics (DOL), Washington, DC.

    "Exploring Careers" is a career education resource program, published in fifteen separate booklets, for junior high school-age students. It provides information about the world of work and offers its readers a way of learning about themselves and relating that information to career choices. The publications aim to build career awareness by means…

  11. Exploration Medical Capability

    Science.gov (United States)

    Watkins, Sharmila; Baumann, David; Wu, Jimmy; Barsten, Kristina

    2010-01-01

    Exploration Medical Capability (ExMC) is an element of NASA's Human Research Program (HRP). ExMC's goal is to address the risk of the Inability to Adequately Recognize or Treat an Ill or Injured Crewmember. This poster highlights the approach ExMC has taken to address this goal and our current areas of interest. The Space Medicine Exploration Medical Condition List (SMEMCL) was created to identify medical conditions of concern during exploration missions. The list was derived from space flight medical incidents, the shuttle medical checklist, the International Space Station medical checklist, and expert opinion. The conditions on the list were prioritized according to mission type by a panel comprised of flight surgeons, physician astronauts, engineers, and scientists. From the prioritized list, the ExMC element determined the capabilities needed to address the medical conditions of concern. Where such capabilities were not currently available, a gap was identified. The element s research plan outlines these gaps and the tasks identified to achieve the desired capabilities for exploration missions. This poster is being presented to inform the audience of the gaps and tasks being investigated by ExMC and to encourage discussions of shared interests and possible future collaborations.

  12. Trends in exploration expenditures

    International Nuclear Information System (INIS)

    The American Petroleum Institute and the Department of Energy have contributed to the U.S. petroleum industry estimates of expenditures in exploration. The estimates of expenditures were for scattered years until 1959; from that year forward a continuous record is available. The petroleum industry in the United States is now spending about $10 billion per year in the search for new oil and gas fields. In 1986 dollars, this level is about that of the 1960s, a period of reduced exploratory effort. In the 1960s and 1970s the industry spent about 25% of its revenue in exploration. In the 1980s the percentage spent in exploration has decreased; in the period 1985 to 1988 the percent of revenue spent in exploring for new oil and gas fields was at or about 15% - a significantly lower level from past history. Levels of exploratory overhead, previously at the level of 10% of revenue, have been about 20% in the 1985 to 1988 period. Expenditure levels tell much about the reinvestment rate of the industry and the optimism or pessimism of those who approve funds for the search for new oil and gas fields

  13. Antarctica: Discovery & Exploration.

    Science.gov (United States)

    Gascoigne, Toss; Collett, Peter

    An examination of Antarctica, from the first sightings to the heroic explorations of the late 18th and early 19th centuries to modern-day research, is presented in this book. Twelve chapters are as follows: (1) The search begins; (2) Whalers and sealers: bites and nibbles; (3) The new continent: first sight; (4) Wintering: the first party; (5)…

  14. Oil Exploration Mapping

    Science.gov (United States)

    1994-01-01

    After concluding an oil exploration agreement with the Republic of Yemen, Chevron International needed detailed geologic and topographic maps of the area. Chevron's remote sensing team used imagery from Landsat and SPOT, combining images into composite views. The project was successfully concluded and resulted in greatly improved base maps and unique topographic maps.

  15. Exploring Sound with Insects

    Science.gov (United States)

    Robertson, Laura; Meyer, John R.

    2010-01-01

    Differences in insect morphology and movement during singing provide a fascinating opportunity for students to investigate insects while learning about the characteristics of sound. In the activities described here, students use a free online computer software program to explore the songs of the major singing insects and experiment with making…

  16. Beam tests of ATLAS SCT silicon strip detector modules

    International Nuclear Information System (INIS)

    The design and technology of the silicon strip detector modules for the Semiconductor Tracker (SCT) of the ATLAS experiment have been finalised in the last several years. Integral to this process has been the measurement and verification of the tracking performance of the different module types in test beams at the CERN SPS and the KEK PS. Tests have been performed to explore the module performance under various operating conditions including detector bias voltage, magnetic field, incidence angle, and state of irradiation up to 3x1014 protons per square centimetre. A particular emphasis has been the understanding of the operational consequences of the binary readout scheme

  17. Exploring the Views of Students on the Use of Facebook in University Teaching and Learning

    Science.gov (United States)

    Donlan, Leah

    2014-01-01

    Facebook use among students is almost ubiquitous; however, its use for formal academic purposes remains contested. Through an online survey monitoring student use of module Facebook pages and focus groups, this study explores students' current academic uses of Facebook and their views on using Facebook within university modules. Students…

  18. Distraction task rather than focal attention modulates gamma activity associated with auditory steady-state responses (ASSRs)

    DEFF Research Database (Denmark)

    Griskova-Bulanova, Inga; Ruksenas, Osvaldas; Dapsys, Kastytis; Maciulis, Valentinas; Arnfred, Sidse Marie Hemmingsen

    2011-01-01

    To explore the modulation of auditory steady-state response (ASSR) by experimental tasks, differing in attentional focus and arousal level.......To explore the modulation of auditory steady-state response (ASSR) by experimental tasks, differing in attentional focus and arousal level....

  19. Strictly homogeneous laterally complete modules

    Science.gov (United States)

    Chilin, V. I.; Karimov, J. A.

    2016-03-01

    Let A be a laterally complete commutative regular algebra and X be a laterally complete A-module. In this paper we introduce a notion of homogeneous and strictly homogeneous A-modules. It is proved that any homogeneous A-module is strictly homogeneous A-module, if the Boolean algebra of all idempotents in A is multi-σ-finite.

  20. Logistics Modeling for Lunar Exploration Systems

    Science.gov (United States)

    Andraschko, Mark R.; Merrill, R. Gabe; Earle, Kevin D.

    2008-01-01

    The extensive logistics required to support extended crewed operations in space make effective modeling of logistics requirements and deployment critical to predicting the behavior of human lunar exploration systems. This paper discusses the software that has been developed as part of the Campaign Manifest Analysis Tool in support of strategic analysis activities under the Constellation Architecture Team - Lunar. The described logistics module enables definition of logistics requirements across multiple surface locations and allows for the transfer of logistics between those locations. A key feature of the module is the loading algorithm that is used to efficiently load logistics by type into carriers and then onto landers. Attention is given to the capabilities and limitations of this loading algorithm, particularly with regard to surface transfers. These capabilities are described within the context of the object-oriented software implementation, with details provided on the applicability of using this approach to model other human exploration scenarios. Some challenges of incorporating probabilistics into this type of logistics analysis model are discussed at a high level.

  1. Relativistic Astrophysics Explorer

    CERN Document Server

    Kaaret, P E

    2003-01-01

    The great success of the Rossi X-Ray Timing Explorer (RXTE) has shown that X-ray timing is an excellent tool for the study of strong gravitational fields and the measurement of fundamental physical properties of black holes and neutron stars. Here, we describe a next-generation X-ray timing mission, the Relativistic Astrophysics Explorer (RAE), designed to fit within the envelope of a medium-sized mission. The instruments will be a narrow-field X-ray detector array with an area of 6 m^2 equal to ten times that of RXTE and a wide-field X-ray monitor. We describe the science made possible with this mission, the design of the instruments, and results on prototype large-area X-ray detectors.

  2. The Relativistic Astrophysics Explorer

    Science.gov (United States)

    Kaaret, P.

    The great success of the Rossi X-Ray Timing Explorer (RXTE) has shown that X-ray timing is an excellent tool for the study of strong gravitational fields and the measurement of fundamental physical properties of black holes and neutron stars. Here, we describe a next-generation X-ray timing mission, the Relativistic Astrophysics Explorer (RAE), designed to fit within the envelope of a medium-sized mission. The instruments will be a narrow-field X-ray detector array with an area of 60,000 cm2 equal to ten times that of RXTE and a wide-field X-ray monitor. We describe the science made possible with this mission, the design of the instruments, and results on prototype large-area X-ray detectors.

  3. The Primordial Inflation Explorer

    Science.gov (United States)

    Kogut, Alan J.

    2012-01-01

    The Primordial Inflation Explorer is an Explorer-class mission to measure the gravity-wave signature of primordial inflation through its distinctive imprint on the linear polarization of the cosmic microwave background. PIXIE uses an innovative optical design to achieve background-limited sensitivity in 400 spectral channels spanning 2.5 decades in frequency from 30 GHz to 6 THz (1 cm to 50 micron wavelength). The principal science goal is the detection and characterization of linear polarization from an inflationary epoch in the early universe, with tensor-to-scalar ratio r < 10(exp -3) at 5 standard deviations. The rich PIXIE data set will also constrain physical processes ranging from Big Bang cosmology to the nature of the first stars to physical conditions within the interstellar medium of the Galaxy. I describe the PIXIE instrument and mission architecture needed to detect the inflationary signature using only 4 semiconductor bolometers.

  4. Exploring textual data

    CERN Document Server

    Lebart, Ludovic; Berry, Lisette

    1998-01-01

    Researchers in a number of disciplines deal with large text sets requiring both text management and text analysis. Faced with a large amount of textual data collected in marketing surveys, literary investigations, historical archives and documentary data bases, these researchers require assistance with organizing, describing and comparing texts. Exploring Textual Data demonstrates how exploratory multivariate statistical methods such as correspondence analysis and cluster analysis can be used to help investigate, assimilate and evaluate textual data. The main text does not contain any strictly mathematical demonstrations, making it accessible to a large audience. This book is very user-friendly with proofs abstracted in the appendices. Full definitions of concepts, implementations of procedures and rules for reading and interpreting results are fully explored. A succession of examples is intended to allow the reader to appreciate the variety of actual and potential applications and the complementary processin...

  5. Autonomous single camera exploration

    OpenAIRE

    Vidal-Calleja, Teresa A.; Sanfeliu, Alberto; Andrade-Cetto, J.

    2006-01-01

    In this paper we present an active exploration strategy for a mobile robot navigating in 3D. The aim is to control a moving robot that autonomously builds a visual feature map while at the same time optimises its localisation in this map. The technique chooses the most appropriate commands maximising the information gain between prior states and measurements, while performing 6DOF bearing only SLAM at video rate. Maximising the mutual information helps the vehicle avoid ill-conditioned measur...

  6. Exploring volumetrically indexed cups

    Science.gov (United States)

    Jones, Dustin L.

    2011-03-01

    This article was inspired by a set of 12 cylindrical cups, which are volumetrically indexed; that is to say, the volume of cup n is equal to n times the volume of cup 1. Various sets of volumetrically indexed cylindrical cups are explored. I demonstrate how this children's toy is ripe for mathematical investigation, with connections to geometry, algebra and differential calculus. Students with an understanding of these topics should be able to complete the analysis and related exercises contained herein.

  7. Juno I -- Explorer I

    Science.gov (United States)

    1958-01-01

    Juno I, a slightly modified Jupiter-C launch vehicle, shortly before the January 31, 1958 launch of America's first satellite, Explorer I. The Jupiter-C, developed by Dr. Wernher von Braun and the rocket team at Redstone Arsenal in Huntsville, Alabama, consisted of a modified version of the Redstone rocket's first stage and two upper stages of clustered Baby Sergeant rockets developed by the Jet Propulsion Laboratory.

  8. Exploring the Visual Landscape

    OpenAIRE

    Nijhuis, S.; Van Lammeren, R.; van Der Hoeven, F

    2011-01-01

    Exploring the Visual Landscape is about the combination of landscape research and planning, visual perception and Geographic Information Science. It showcases possible ways of getting a grip on themes like: landscape openness, cluttering of the rural landscape, high-rise buildings in relation to cityscape, historic landscapes and motorway panoramas. It offers clues for visual landscape assessment of spaces in cities, parks and rural areas. In that respect, it extends the long tradition in the...

  9. Exploring Embodied Wellbeing

    OpenAIRE

    Bunne, Astrid

    2013-01-01

    Phenomenological theory and neuroscience suggest that there is no mind-body separation. Yet current mental healthcare services focus mainly on cognitive aspects of the individual in their interventions of depression and anxiety. In consonance with the recent shift from a pathological dominance to a focus on wellbeing, this study acknowledges neglected areas of body and wellbeing in psychological research and healthcare practices by exploring the concept of ‘embodied wellbeing.’ Using particip...

  10. Interactive Chemical Reactivity Exploration

    OpenAIRE

    Haag, Moritz P.; Vaucher, Alain C.; Bosson, Mael; Redon, Stephane; Reiher, Markus

    2014-01-01

    Elucidating chemical reactivity in complex molecular assemblies of a few hundred atoms is, despite the remarkable progress in quantum chemistry, still a major challenge. Black-box search methods to find intermediates and transition-state structures might fail in such situations because of the high-dimensionality of the potential energy surface. Here, we propose the concept of interactive chemical reactivity exploration to effectively introduce the chemist's intuition into the search process. ...

  11. Separation film module. Bunri maku module

    Energy Technology Data Exchange (ETDEWEB)

    Ninomiya, Y.; Takada, N. (, Chiba (Japan))

    1990-10-09

    The separation film module used for the production of dry air by separating vapor from air and for the concentration of alcohol from a mixed gas of alcohol and water has hollow yarn of polyimide resin in a tubular container. The gas permeated through the separation film is discharged from the permeated gas exit provided at an end of the container, and the unpermeated gas is exhausted from the core pipe provided at the center of the tubulsr container. However, the module has a problem of poor airtightness at the connection when the machining is not accurate or when thermal expansion occurs because the core pipe is communicated with the unpermeated gas discharge pipe via a rigid joint pipe. This invention relates to a solution to the problem by providing an expansion joint between the discharge end of the core pipe and the unpermeated gas discharge pipe. A joint pipe with a bellows in the middle is used as the said joint pipe. 3 figs.

  12. Solar cell module. Taiyo denchi module

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Akihiko; Matsumoto, Hitoshi.

    1989-09-06

    In the conventional solar cell module, the cell cost is elevated because the cross sections of the cell edge is surrounded with frames of various shape and the gap is filled with a sealant. In additionn, the top end of the module frame is placed roughly 1 mm above the glass surface; the photoelectromotive force part is covered with such deposits as soils and sands, thus badly affecting the photovoltaic generation. In this invention, weather-proof opaque paint is coated around the surface glass to interrupt the light irradiation to the adhesive resin layer between the glass and the back sheet, thus preventing the degradation of the resin layer. Cost is low because of using a thin film. The light interruption by the deposits can be prevented. The photoelectromotive force element is a n-type CdS film or CdS/CdTe. The resin layer around the glass is a thermoplastic polyolefin which is modified with acid anhydrides. 5 figs.

  13. Bunch identification module

    International Nuclear Information System (INIS)

    This module provides bunch identification and timing signals for the PEP Interaction areas. Timing information is referenced to the PEP master oscillator, and adjusted in phase as a function of region. Identification signals are generated in a manner that allows observers in all interaction regions to agree on an unambiguous bunch identity. The module provides bunch identification signals via NIM level logic, upon CAMAC command, and through LED indicators. A front panel ''region select'' switch allows the same module to be used in all regions. The module has two modes of operation: a bunch identification mode and a calibration mode. In the identification mode, signals indicate which of the three bunches of electrons and positrons are interacting, and timing information about beam crossing is provided. The calibration mode is provided to assist experimenters making time of flight measurements. In the calibration mode, three distinct gating signals are referenced to a selected bunch, allowing three timing systems to be calibrated against a common standard. Physically, the bunch identifier is constructed as a single width CAMAC module. 2 figs., 1 tab

  14. Bayesian Adaptive Exploration

    Science.gov (United States)

    Loredo, Thomas J.

    2004-04-01

    I describe a framework for adaptive scientific exploration based on iterating an Observation-Inference-Design cycle that allows adjustment of hypotheses and observing protocols in response to the results of observation on-the-fly, as data are gathered. The framework uses a unified Bayesian methodology for the inference and design stages: Bayesian inference to quantify what we have learned from the available data and predict future data, and Bayesian decision theory to identify which new observations would teach us the most. When the goal of the experiment is simply to make inferences, the framework identifies a computationally efficient iterative ``maximum entropy sampling'' strategy as the optimal strategy in settings where the noise statistics are independent of signal properties. Results of applying the method to two ``toy'' problems with simulated data-measuring the orbit of an extrasolar planet, and locating a hidden one-dimensional object-show the approach can significantly improve observational efficiency in settings that have well-defined nonlinear models. I conclude with a list of open issues that must be addressed to make Bayesian adaptive exploration a practical and reliable tool for optimizing scientific exploration.

  15. Exploration EVA System

    Science.gov (United States)

    Kearney, Lara

    2004-01-01

    In January 2004, the President announced a new Vision for Space Exploration. NASA's Office of Exploration Systems has identified Extravehicular Activity (EVA) as a critical capability for supporting the Vision for Space Exploration. EVA is required for all phases of the Vision, both in-space and planetary. Supporting the human outside the protective environment of the vehicle or habitat and allow ing him/her to perform efficient and effective work requires an integrated EVA "System of systems." The EVA System includes EVA suits, airlocks, tools and mobility aids, and human rovers. At the core of the EVA System is the highly technical EVA suit, which is comprised mainly of a life support system and a pressure/environmental protection garment. The EVA suit, in essence, is a miniature spacecraft, which combines together many different sub-systems such as life support, power, communications, avionics, robotics, pressure systems and thermal systems, into a single autonomous unit. Development of a new EVA suit requires technology advancements similar to those required in the development of a new space vehicle. A majority of the technologies necessary to develop advanced EVA systems are currently at a low Technology Readiness Level of 1-3. This is particularly true for the long-pole technologies of the life support system.

  16. NREL module energy rating methodology

    Energy Technology Data Exchange (ETDEWEB)

    Whitaker, C.; Newmiller, J.; Kroposki, B. [National Renewable Energy Laboratory, Golden, CO (United States)] [and others

    1995-11-01

    The goals of this project were to develop a tool for: evaluating one module in different climates; comparing different modules; provide a Q&D method for estimating periodic energy production; provide an achievable module rating; provide an incentive for manufacturers to optimize modules to non-STC conditions; and to have a consensus-based, NREL-sponsored activity. The approach taken was to simulate module energy for five reference days of various weather conditions. A performance model was developed.

  17. Hilbert modules and their representation

    OpenAIRE

    Takahaschi, Alfonso

    2012-01-01

    A Hilbert module over a  C*-algebra A with identity is an unitary A-module H, endowed with an inner product taking values in A. We consider these modules and derive some of their elementary properties. Later we consider fields of Hilbert modules and obtain a representation of H by means of continuous sections. This result will be used in other papers ([7] and [8]) to get a duality  theorem and to study special Hilbert modules.

  18. Primordial Inflation Polarization Explorer (Phase 2)

    Science.gov (United States)

    Kogurt, Alan; Bennett, Charles

    This is the Lead Proposal for the proposed investigation "Primordial Inflation Polarization Explorer (Phase 2)" We propose to fly the Primordial Inflation Polarization Explorer (PIPER) to measure the polarization of the cosmic microwave background (CMB) and search for the imprint of gravitational waves produced during an inflationary epoch in the early universe. Such a signal is expected to exist: the simplest inflation models predict tensor-to-scalar ratio 0.01 optimized to detect the inflationary signal on large angular scales. It consists of two co-aligned telescopes cooled to 1.5 K within a large liquid helium bucket dewar. A variable-delay polarization modulator (VPM) on each telescope chops between linear and circular polarization to isolate the polarized signal while rejecting the much brighter unpolarized emission. PIPER's innovative architecture combines cryogenic optics with kilo-pixel detector arrays to provide unprecedented sensitivity to CMB polarization. The fast modulation between linear and circular polarization takes advantage of the lack of astrophysical circular polarization to eliminate common sources of systematic error. The sensitivity and control of systematic errors in turn enable measurements over most of the sky from mid-latitude launch sites; long-duration Antarctic flights are not required. With sensitivity r proposed work, including detector development, polarization modulation, instrument integration, and cryogenic ballooning. The team includes the Instrument Integration Lead and Instrument Test Lead for the Wilkinson Microwave Anisotropy Probe (WMAP) as well as the lead authors for the systematic error papers for the ground-breaking COBE-DMR, COBE-FIRAS, and WMAP instruments. The team has demonstrated expertise in data analysis including pipeline development, foreground modeling, and cosmological parameter fitting. PIPER began development in 2009 and is nearing completion. With first flight scheduled soon, the development schedule

  19. Modulations physiologiques et comportementales de la douleur sociale

    OpenAIRE

    Cristofori, Irène

    2011-01-01

    Pain is a form of social non-physical pain arising from the perception of social exclusion. The importance of understanding its behavioral and neuronal modulations has a critical value, since its long lasting consequences can be extremely harmful. In this thesis I firstly explored these issues through a behavioral SCR study (Skin Conductance Recording), and successively through three iEEG studies in patients with epilepsy (intracranial EEG). The SCR study explored the direction in which socia...

  20. Multilevel Modulation formats for Optical Communication

    DEFF Research Database (Denmark)

    Jensen, Jesper Bevensee

    2008-01-01

    This thesis studies the use of multilevel modulation formats for optical communication systems. Multilevel modulation is an attractive method of increasing the spectral efficiency of optical communication systems. Various modulation formats employing phase modulation, amplitude modulation or a...

  1. Phase modulated multiphoton microscopy

    CERN Document Server

    Karki, Khadga Jung; Pullerits, Tonu

    2015-01-01

    We show that the modulation of the phases of the laser beams of ultra-short pulses leads to modulation of the two photon fluorescence intensity. The phase modulation technique when used in multi-photon microscopy can improve the signal to noise ratio. The technique can also be used in multiplexing the signals in the frequency domain in multi-focal raster scanning microscopy. As the technique avoids the use of array detectors as well as elaborate spatiotemporal multiplexing schemes it provides a convenient means to multi-focal scanning in axial direction. We show examples of such uses. Similar methodology can be used in other non-linear scanning microscopies, such as second or third harmonic generation microscopy.

  2. Hollow dimension of modules

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In this paper, we are interested in the following general question: Given a module Mwhich has finite hollow dimension and which has a finite collection of submodules Ki (1≤i≤n) such that M=K1+... +Kn, can we find an expression for the hollow dimension of Min terms of hollow dimensions of modules built up in some way from K1 Kn? We prove the following theorem:Let Mbe an amply supplemented module having finite hollow dimension and let Ki (1≤i≤n) be a finite collection of submodules of Msuch that M=K1+...+Kn. Then the hollow dimension h(M) of Mis the sum of the hollow dimensions of Ki (1≤i≤n) ifand only if Ki is a supplement of K1+...+Ki-1+Ki+1+...+Kn in Mfor each 1≤i≤n.

  3. Flat covers of modules

    CERN Document Server

    Xu, Jinzhong

    1996-01-01

    Since the injective envelope and projective cover were defined by Eckmann and Bas in the 1960s, they have had great influence on the development of homological algebra, ring theory and module theory. In the 1980s, Enochs introduced the flat cover and conjectured that every module has such a cover over any ring. This book provides the uniform methods and systematic treatment to study general envelopes and covers with the emphasis on the existence of flat cover. It shows that Enochs' conjecture is true for a large variety of interesting rings, and then presents the applications of the results. Readers with reasonable knowledge in rings and modules will not have difficulty in reading this book. It is suitable as a reference book and textbook for researchers and graduate students who have an interest in this field.

  4. Quantitative velocity modulation spectroscopy

    Science.gov (United States)

    Hodges, James N.; McCall, Benjamin J.

    2016-05-01

    Velocity Modulation Spectroscopy (VMS) is arguably the most important development in the 20th century for spectroscopic study of molecular ions. For decades, interpretation of VMS lineshapes has presented challenges due to the intrinsic covariance of fit parameters including velocity modulation amplitude, linewidth, and intensity. This limitation has stifled the growth of this technique into the quantitative realm. In this work, we show that subtle changes in the lineshape can be used to help address this complexity. This allows for determination of the linewidth, intensity relative to other transitions, velocity modulation amplitude, and electric field strength in the positive column of a glow discharge. Additionally, we explain the large homogeneous component of the linewidth that has been previously described. Using this component, the ion mobility can be determined.

  5. Power module assembly

    Science.gov (United States)

    Campbell, Jeremy B.; Newson, Steve

    2011-11-15

    A power module assembly of the type suitable for deployment in a vehicular power inverter, wherein the power inverter has a grounded chassis, is provided. The power module assembly comprises a conductive base layer electrically coupled to the chassis, an insulating layer disposed on the conductive base layer, a first conductive node disposed on the insulating layer, a second conductive node disposed on the insulating layer, wherein the first and second conductive nodes are electrically isolated from each other. The power module assembly also comprises a first capacitor having a first electrode electrically connected to the conductive base layer, and a second electrode electrically connected to the first conductive node, and further comprises a second capacitor having a first electrode electrically connected to the conductive base layer, and a second electrode electrically connected to the second conductive node.

  6. Individualized training module

    International Nuclear Information System (INIS)

    An individualized training module is a device for providing an individual trainee with the training he needs in a format where he can proceed on his own, without regard for the capabilities or even the presence of other students. It is based on a pretest, each item of which is referenced to a training activity. Each activity also has a test or performance qualification to verify that the desired learning occurred. Typically, the module as a variety of training activities; the scope is purposely narrow; and the instructional materials combine commercial and instructor made materials. The instructor creates the activities based upon desired scope and depth and the training materials and budget available

  7. Photovoltaic concentrator module technology

    Science.gov (United States)

    Richards, Elizabeth H.; Chamberlin, Jay L.; Boes, Eldon C.

    Significant developments in the development of photovoltaic (PV) concentrator technology are described. Concentrator cell research, advances in PV concentrator cell technology, and PV concentrator module development are described. Reliability issues currently of concern, including the applicability of wet insulation resistance tests to concentrator modules, correlation of accelerated thermal cycling tests with life expectancy in the field, and the importance of quality assurance during manufacture, are discussed. Two PV concentrator power systems installed in 1989 are discussed. A PV concentrator initiative program established by the DOE is given, and the results of the latest cost study are presented.

  8. Automation and robotics for Human MARS Exploration

    Science.gov (United States)

    von Richter, L. A. J.; Griethe, W.; Hofmann, P.; Putz, P.

    2002-01-01

    for a human exploration mission. The Human Exploration Mission (HEM) will establish an infrastructure on the surface of Mars co- operating with a tele-communication system located in an orbit around Mars. The landed elements of the Mars Base will be scattered on the Mars surface and they need to be transported by a dedicated system to the Mars Base i.e. by the so called Utility Truck. Furthermore the Utility Truck shall support the assembly of the Mars base elements infrastructure and the subsequent operations on the Martian surface. The infrastructure on Mars shall consist of habitation and laboratory modules, a bio/greenhouse, a mobile pressurised laboratory, landers, an astronaut return vehicle, an in-situ resources utilisation facility and a power generation unit. Besides these elements constituting the human base infrastructure it will comprise astronaut remotely-controlled rovers and rovers with various degrees of autonomy. Figure 1: The Mobile Pressurised Laboratory (by Astrium) The following A&R systems and subsystems are considered to be key elements for a Robotic and finally a Human Exploration of Mars: Europe has to achieve a key role within the A&R devices. It has to be pointed out, however, that it will be essential for the success of future European Mars exploration activities that this effort will be conducted in co-ordination with other space agencies around the world.

  9. Comprehensive Healthcare module: medical and pharmacy students’ shared learning experiences

    Directory of Open Access Journals (Sweden)

    Chai-Eng Tan

    2014-10-01

    Full Text Available Introduction: The Comprehensive Healthcare (CHC module was developed to introduce pre-clinical medical and pharmacy students to the concept of comprehensive healthcare. This study aims to explore their shared learning experiences within this module. Methodology: During this module, medical and pharmacy students conducted visits to patients’ homes and to related community-based organisations in small groups. They were required to write a reflective journal on their experiences regarding working with other professions as part of their module assessment. Highly scored reflective journals written by students from the 2011/2012 academic session were selected for analysis. Their shared learning experiences were identified via thematic analysis. We also analysed students’ feedback regarding the module. Results: Analysis of 25 selected reflective journals revealed several important themes: ‘Understanding of impact of illness and its relation to holistic care’, ‘Awareness of the role of various healthcare professions’ and ‘Generic or soft skills for inter-professional collaboration’. Although the primary objective of the module was to expose students to comprehensive healthcare, the students learnt skills required for future collaborative practice from their experiences. Discussion: The CHC module provided early clinical exposure to community-based health issues and incorporated some elements of inter-professional education. The students learnt about the roles of other healthcare professions and acquired soft skills required for future collaborative practice during this module.

  10. Transcriptional modules related to hepatocellular carcinoma survival: coexpression network analysis.

    Science.gov (United States)

    Xu, Xinsen; Zhou, Yanyan; Miao, Runchen; Chen, Wei; Qu, Kai; Pang, Qing; Liu, Chang

    2016-06-01

    We performed weighted gene coexpression network analysis (WGCNA) to gain insights into the molecular aspects of hepatocellular carcinoma (HCC). Raw microarray datasets (including 488 samples) were downloaded from the Gene Expression Omnibus (GEO) website. Data were normalized using the RMA algorithm. We utilized the WGCNA to identify the coexpressed genes (modules) after non-specific filtering. Correlation and survival analyses were conducted using the modules, and gene ontology (GO) enrichment was applied to explore the possible mechanisms. Eight distinct modules were identified by the WGCNA. Pink and red modules were associated with liver function, whereas turquoise and black modules were inversely correlated with tumor staging. Poor outcomes were found in the low expression group in the turquoise module and in the high expression group in the red module. In addition, GO enrichment analysis suggested that inflammation, immune, virus-related, and interferon-mediated pathways were enriched in the turquoise module. Several potential biomarkers, such as cyclin-dependent kinase 1 (CDK1), topoisomerase 2α (TOP2A), and serpin peptidase inhibitor clade C (antithrombin) member 1 (SERPINC1), were also identified. In conclusion, gene signatures identified from the genome-based assays could contribute to HCC stratification. WGCNA was able to identify significant groups of genes associated with cancer prognosis. PMID:27052251

  11. Magnetically modulated fluorescent probes in turbid media

    CERN Document Server

    Yang,; Chen, Hongyu; Anker, Jeffrey N

    2010-01-01

    Magnetically modulated optical nanoprobes (MagMOONs) were used to detect and distinguish probe fluorescence from autofluorescent backgrounds in turbid media. MagMOONs are micro/nano-sized particles with magnetically controlled orientation and orientation-dependent fluorescence. These probes blink when they rotate in response to rotating external magnetic fields. This blinking signal can be separated from backgrounds enabling spectrochemical sensing in media with strong autofluorescence. We explore the effect of scattering on MagMOON fluorescence. Turbid media reduce the modulated MagMOON signal due to a combination of attenuation of fluorescence signal and reduction in contrast between "On" and "Off" states. The blinking MagMOON fluorescence spectrum can be detected in turbid non-dairy creamer solution with extinction 2.0, and through 9 mm of chicken breast tissue, suggesting that whole mouse imaging is feasible by using this strategy.

  12. Exploring Monte Carlo methods

    CERN Document Server

    Dunn, William L

    2012-01-01

    Exploring Monte Carlo Methods is a basic text that describes the numerical methods that have come to be known as "Monte Carlo." The book treats the subject generically through the first eight chapters and, thus, should be of use to anyone who wants to learn to use Monte Carlo. The next two chapters focus on applications in nuclear engineering, which are illustrative of uses in other fields. Five appendices are included, which provide useful information on probability distributions, general-purpose Monte Carlo codes for radiation transport, and other matters. The famous "Buffon's needle proble

  13. Exploring yawning with neuroimaging.

    Science.gov (United States)

    Nahab, Fatta B

    2010-01-01

    The neural mechanisms responsible for spontaneous yawning as well as contagious yawning are not well characterized. Neuroimaging is an essential tool for helping to identify the seminal neural structures and their inter-related functions to carry out this complex stereotyped motor program. Studies to date have explored the structural neural correlates of yawning through a series of lesion-based case reports and identified participatory structures at various levels of the central nervous system. Functional neuroimaging methods like fMRI have also shed led on the genesis of contagious yawning, though cohesive models explaining the neural mechanisms of contagious motor programs such as yawning remain limited. PMID:20357471

  14. Exploring rationality in schizophrenia

    DEFF Research Database (Denmark)

    Revsbech, Rasmus; Mortensen, Erik Lykke; Owen, Gareth;

    2015-01-01

    Background Empirical studies of rationality (syllogisms) in patients with schizophrenia have obtained different results. One study found that patients reason more logically if the syllogism is presented through an unusual content. Aims To explore syllogism-based rationality in schizophrenia. Method...... Thirty-eight first-admitted patients with schizophrenia and 38 healthy controls solved 29 syllogisms that varied in presentation content (ordinary v. unusual) and validity (valid v. invalid). Statistical tests were made of unadjusted and adjusted group differences in models adjusting for intelligence and...... differences became non-significant. Conclusions When taking intelligence and neuropsychological performance into account, patients with schizophrenia and controls perform similarly on syllogism tests of rationality....

  15. 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

  16. Exploring C++ 11

    CERN Document Server

    Lischner, Ray

    2014-01-01

    Exploring C++ divides C++ up into bite-sized chunks that will help you learn the language one step at a time. Assuming no familiarity with C++, or any other C-based language, you'll be taught everything you need to know in a logical progression of small lessons that you can work through as quickly or as slowly as you need.C++ can be a complicated language. Writing even the most straight-forward of programs requires you to understand many disparate aspects of the language and how they interact with one another. C++ doesn't lend itself to neat compartmentalization the way other languages do. Rat

  17. Uranium exploration techniques

    International Nuclear Information System (INIS)

    The subject is discussed under the headings: introduction (genetic description of some uranium deposits; typical concentrations of uranium in the natural environment); sedimentary host rocks (sandstones; tabular deposits; roll-front deposits; black shales); metamorphic host rocks (exploration techniques); geologic techniques (alteration features in sandstones; favourable features in metamorphic rocks); geophysical techniques (radiometric surveys; surface vehicle methods; airborne methods; input surveys); geochemical techniques (hydrogeochemistry; petrogeochemistry; stream sediment geochemistry; pedogeochemistry; emanometry; biogeochemistry); geochemical model for roll-front deposits; geologic model for vein-like deposits. (U.K.)

  18. Time Series Explorer

    Science.gov (United States)

    Loredo, Thomas

    The key, central objectives of the proposed Time Series Explorer project are to develop an organized collection of software tools for analysis of time series data in current and future NASA astrophysics data archives, and to make the tools available in two ways: as a library (the Time Series Toolbox) that individual science users can use to write their own data analysis pipelines, and as an application (the Time Series Automaton) providing an accessible, data-ready interface to many Toolbox algorithms, facilitating rapid exploration and automatic processing of time series databases. A number of time series analysis methods will be implemented, including techniques that range from standard ones to state-of-the-art developments by the proposers and others. Most of the algorithms will be able to handle time series data subject to real-world problems such as data gaps, sampling that is otherwise irregular, asynchronous sampling (in multi-wavelength settings), and data with non-Gaussian measurement errors. The proposed research responds to the ADAP element supporting the development of tools for mining the vast reservoir of information residing in NASA databases. The tools that will be provided to the community of astronomers studying variability of astronomical objects (from nearby stars and extrasolar planets, through galactic and extragalactic sources) will revolutionize the quality of timing analyses that can be carried out, and greatly enhance the scientific throughput of all NASA astrophysics missions past, present, and future. The Automaton will let scientists explore time series - individual records or large data bases -- with the most informative and useful analysis methods available, without having to develop the tools themselves or understand the computational details. Both elements, the Toolbox and the Automaton, will enable deep but efficient exploratory time series data analysis, which is why we have named the project the Time Series Explorer. Science

  19. Significance of biofilm proteins in modulating cyprid metamorphosis of Balanus amphitrite (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.; KrishnaKumar, S.

    The role of biofilm proteins in modulating cyprid metamorphosis is not well understood. In the present investigation this possibility was explored by disrupting biofilm proteins using commercially available protease. The influence of natural biofilm...

  20. Modulation of the Post-Ischemic Immune Response to Improve Stroke Outcome

    OpenAIRE

    Becker, Kyra J.

    2010-01-01

    Recent advances in understanding how the post-stroke immune response may contribute to ischemic brain injury are discussed. In particular, the potential of modulating the post-ischemic immune response to improve stroke outcome is explored.

  1. Cadmium telluride module development

    Energy Technology Data Exchange (ETDEWEB)

    Albrigth, S.P.; Chamberlin, R.R.; Jordan, J.F. (Photon Energy, Inc., El Paso, TX (USA))

    1991-05-01

    Efficiencies of up to 12.3% have been achieved on small devices. It is expected that 14% efficiency will be exceeded on small devices by improving the fill factors on the present devices in the reasonably near future. Efficiencies in the range 16%-18% are expected to be achieved in the longer term. Modules of 6 W, approximately 929 cm{sup 2} in area with an active area efficiency of over 8% (aperture efficiency of 7.3%) have been achieved. The feasibility of producing 4 ft{sup 2} modules of CdS/CdTe has been shown and requires further efforts in order to realize the overall potentials. The structural integrity of the encapsulation design has been studied by thermal cycling and outdoor life testing. Submodules have been life tested for over 270 days with no observable degradation by the SERI Outdoor Reliability and Life Testing Laboratory. In addition to further optimization of materials and device structure, module output in the future will be increased by an improvement in the uniformity of the deposition process, and by minimizing the loss of active area due to cell division interconnections. Module output is expected to attain 135 W m{sup -2} in the mid 1990s and over 150 W m{sup -2} in the long term. (orig.).

  2. Modulated Luminescent Tomography

    OpenAIRE

    Stefanov, Plamen; Cong, Wenxiang; Wang, Ge

    2014-01-01

    We propose and analyze a mathematical model of Modulated Luminescent Tomography. We show that when single X-rays or focused X-rays are used as an excitation, the problem is similar to the inversion of weighted X-ray transforms. In particular, we give an explicit inversion in the case of Dual Cone X-ray excitation.

  3. Modelling the Photovoltaic Module

    DEFF Research Database (Denmark)

    Katsanevakis, Markos

    2011-01-01

    This paper refers into various ways in simulation the Photovoltaic (PV) module behaviour under any combination of solar irradiation and ambient temperature. There are three different approaches presented here briefly and one of them is chosen because of its good accuracy and relatively low...

  4. Special Attachments. Module 19.

    Science.gov (United States)

    South Carolina State Dept. of Education, Columbia. Office of Vocational Education.

    This module on special attachments, one in a series dealing with industrial sewing machines, their attachments, and operation, covers four topics: gauges; cording attachment; zipper foot; and hemming, shirring, and binding. For each topic these components are provided: an introduction, directions, an objective, learning activities, student…

  5. Special Operation. Module 20.

    Science.gov (United States)

    South Carolina State Dept. of Education, Columbia. Office of Vocational Education.

    This module on special operations, one in a series dealing with industrial sewing machines, their attachments, and operation, covers two topics: topstitching and mitering. For each topic these components are provided: an introduction, directions, an objective, learning activities, student information, a student self-check, and a check-out…

  6. ALICE silicon strip module

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    This small silicon detector strip will be inserted into the inner tracking system (ITS) on the ALICE detector at CERN. This detector relies on state-of-the-art particle tracking techniques. These double-sided silicon strip modules have been designed to be as lightweight and delicate as possible as the ITS will eventually contain five square metres of these devices.

  7. Mars Exploration Rover mission

    Science.gov (United States)

    Crisp, Joy A.; Adler, Mark; Matijevic, Jacob R.; Squyres, Steven W.; Arvidson, Raymond E.; Kass, David M.

    2003-10-01

    In January 2004 the Mars Exploration Rover mission will land two rovers at two different landing sites that show possible evidence for past liquid-water activity. The spacecraft design is based on the Mars Pathfinder configuration for cruise and entry, descent, and landing. Each of the identical rovers is equipped with a science payload of two remote-sensing instruments that will view the surrounding terrain from the top of a mast, a robotic arm that can place three instruments and a rock abrasion tool on selected rock and soil samples, and several onboard magnets and calibration targets. Engineering sensors and components useful for science investigations include stereo navigation cameras, stereo hazard cameras in front and rear, wheel motors, wheel motor current and voltage, the wheels themselves for digging, gyros, accelerometers, and reference solar cell readings. Mission operations will allow commanding of the rover each Martian day, or sol, on the basis of the previous sol's data. Over a 90-sol mission lifetime, the rovers are expected to drive hundreds of meters while carrying out field geology investigations, exploration, and atmospheric characterization. The data products will be delivered to the Planetary Data System as integrated batch archives.

  8. Human exploration mission studies

    Science.gov (United States)

    Cataldo, Robert L.

    1989-01-01

    The Office of Exploration has established a process whereby all NASA field centers and other NASA Headquarters offices participate in the formulation and analysis of a wide range of mission strategies. These strategies were manifested into specific scenarios or candidate case studies. The case studies provided a systematic approach into analyzing each mission element. First, each case study must address several major themes and rationale including: national pride and international prestige, advancement of scientific knowledge, a catalyst for technology, economic benefits, space enterprise, international cooperation, and education and excellence. Second, the set of candidate case studies are formulated to encompass the technology requirement limits in the life sciences, launch capabilities, space transfer, automation, and robotics in space operations, power, and propulsion. The first set of reference case studies identify three major strategies: human expeditions, science outposts, and evolutionary expansion. During the past year, four case studies were examined to explore these strategies. The expeditionary missions include the Human Expedition to Phobos and Human Expedition to Mars case studies. The Lunar Observatory and Lunar Outpost to Early Mars Evolution case studies examined the later two strategies. This set of case studies established the framework to perform detailed mission analysis and system engineering to define a host of concepts and requirements for various space systems and advanced technologies. The details of each mission are described and, specifically, the results affecting the advanced technologies required to accomplish each mission scenario are presented.

  9. Exploration Supply Chain Simulation

    Science.gov (United States)

    2008-01-01

    The Exploration Supply Chain Simulation project was chartered by the NASA Exploration Systems Mission Directorate to develop a software tool, with proper data, to quantitatively analyze supply chains for future program planning. This tool is a discrete-event simulation that uses the basic supply chain concepts of planning, sourcing, making, delivering, and returning. This supply chain perspective is combined with other discrete or continuous simulation factors. Discrete resource events (such as launch or delivery reviews) are represented as organizational functional units. Continuous resources (such as civil service or contractor program functions) are defined as enabling functional units. Concepts of fixed and variable costs are included in the model to allow the discrete events to interact with cost calculations. The definition file is intrinsic to the model, but a blank start can be initiated at any time. The current definition file is an Orion Ares I crew launch vehicle. Parameters stretch from Kennedy Space Center across and into other program entities (Michaud Assembly Facility, Aliant Techsystems, Stennis Space Center, Johnson Space Center, etc.) though these will only gain detail as the file continues to evolve. The Orion Ares I file definition in the tool continues to evolve, and analysis from this tool is expected in 2008. This is the first application of such business-driven modeling to a NASA/government-- aerospace contractor endeavor.

  10. Product Module Rig Test

    Science.gov (United States)

    Holdeman, James D. (Technical Monitor); Chiappetta, Louis, Jr.; Hautman, Donald J.; Ols, John T.; Padget, Frederick C., IV; Peschke, William O. T.; Shirley, John A.; Siskind, Kenneth S.

    2004-01-01

    The low emissions potential of a Rich-Quench-Lean (RQL) combustor for use in the High Speed Civil Transport (HSCT) application was evaluated as part of Work Breakdown Structure (WBS) 1.0.2.7 of the NASA Critical Propulsion Components (CPC) Program under Contract NAS3-27235. Combustion testing was conducted in cell 1E of the Jet Burner Test Stand at United Technologies Research Center. Specifically, a Rich-Quench-Lean combustor, utilizing reduced scale quench technology implemented in a quench vane concept in a product-like configuration (Product Module Rig), demonstrated the capability of achieving an emissions index of nitrogen oxides (NOx EI) of 8.5 gm/Kg fuel at the supersonic flight condition (relative to the program goal of 5 gm/Kg fuel). Developmental parametric testing of various quench vane configurations in the more fundamental flametube, Single Module Rig Configuration, demonstrated NOx EI as low as 5.2. All configurations in both the Product Module Rig configuration and the Single Module Rig configuration demonstrated exceptional efficiencies, greater than 99.95 percent, relative to the program goal of 99.9 percent efficiency at supersonic cruise conditions. Sensitivity of emissions to quench orifice design parameters were determined during the parametric quench vane test series in support of the design of the Product Module Rig configuration. For the rectangular quench orifices investigated, an aspect ratio (length/width) of approximately 2 was found to be near optimum. An optimum for orifice spacing was found to exist at approximately 0.167 inches, resulting in 24 orifices per side of a quench vane, for the 0.435 inch quench zone channel height investigated in the Single Module Rig. Smaller quench zone channel heights appeared to be beneficial in reducing emissions. Measurements were also obtained in the Single Module Rig configuration on the sensitivity of emissions to the critical combustor parameters of fuel/air ratio, pressure drop, and residence

  11. Fundamentals of spread spectrum modulation

    CERN Document Server

    Ziemer, Rodger E

    2007-01-01

    This lecture covers the fundamentals of spread spectrum modulation, which can be defined as any modulation technique that requires a transmission bandwidth much greater than the modulating signal bandwidth, independently of the bandwidth of the modulating signal. After reviewing basic digital modulation techniques, the principal forms of spread spectrum modulation are described. One of the most important components of a spread spectrum system is the spreading code, and several types and their characteristics are described. The most essential operation required at the receiver in a spread spect

  12. The Needs Analysis in Self-Concept Module Development

    Science.gov (United States)

    Yusop, Yusni Mohamad; Sumari, Melati; Mohamed, Fatanah; Said, Shahriza; Azeez, Mohd Ibrahim K.; Jamil, Mohd Ridhuan Mohd

    2015-01-01

    This research studies needs analyses conducted to examine the need for a self-concept module. Two types of analyses had been conducted; content analysis and experts' consensus. Content analysis was conducted to explore the issues of self-concept from the theory and literature perspective. Later, needs analysis had also been carried out to observe…

  13. Nanomedicine Approaches to Modulate Neural Stem Cells in Brain Repair.

    Science.gov (United States)

    Santos, Tiago; Boto, Carlos; Saraiva, Cláudia M; Bernardino, Liliana; Ferreira, Lino

    2016-06-01

    We explore the concept of modulating neural stem cells and their niches for brain repair using nanotechnology-based approaches. These approaches include stimulating cell proliferation, recruitment, and differentiation to functionally recover damaged areas. Nanoscale-engineered materials potentially overcome limited crossing of the blood-brain barrier, deficient drug delivery, and cell targeting. PMID:26917252

  14. Geothermal Energy: Resource and Utilization. A Teaching Module.

    Science.gov (United States)

    Nguyen, Van Thanh

    The search for new energy resources as alternatives to fossil fuels have generated new interest in the heat of the earth itself. New geothermal areas with a variety of characteristics are being explored, as are new ways of extracting work from naturally heated steam and hot water. Some of this effort is discussed in this three-part module. Five…

  15. Development of protected cartographic database generating parallel module

    OpenAIRE

    GIBADULLIN R.; RAHMATULLIN F.; RIYANOV R.

    2015-01-01

    This article explores the possibilities of geographic information system QGIS to work with DBMS PostgreSQL. Software module for parallel encryption/decryption of cartographic data has been developed and its further analyze on test database in order to get experimental evaluation of encryption/decryption speed was made

  16. Improving FCS Accountability: Increasing STEM Awareness with Interior Design Modules

    Science.gov (United States)

    Etheredge, Jessica; Moody, Dana; Cooper, Ashley

    2014-01-01

    This paper demonstrates ways in which family and consumer sciences (FCS) educators can explore more opportunities to integrate Science, Technology, Engineering, and Math (STEM) principles into secondary education curriculum. Interior design is used as a case study for creating learning modules that incorporate STEM principles in a creative and…

  17. Outsourcing R&D Modules of a New Developing Technology

    DEFF Research Database (Denmark)

    Pedersen, Jørgen Lindgaard; Perunovic, Zoran

    2004-01-01

    The paper explores some of the dimensions of the R&D processes: modularity, uncertainty and outsourcing. Ways to divide R&D effort into modules and to argue, either in direction of its modularity, or interdependency, are presented. Further on, uncertainties are segmented into the majors and minor...

  18. Lunar Module 5 mated with Spacecraft Lunar Module Adapter (SLA)

    Science.gov (United States)

    1969-01-01

    Interior view of the Kennedy Space Center's (KSC) Manned Spacecraft Operations Building showing Lunar Module 5 mated to its Spacecraft Lunar Module Adapter (SLA). LM-5 is scheduled to be flown on the Apollo 11 lunar landing mission.

  19. Seeing red: affect modulation and chromatic color responses on the Rorschach.

    Science.gov (United States)

    Malone, Johanna C; Stein, Michelle B; Slavin-Mulford, Jenelle; Bello, Iruma; Sinclair, S Justin; Blais, Mark A

    2013-01-01

    Psychoanalytic theories suggest that color perception on the Rorschach relates to affective modulation. However, this idea has minimal empirical support. Using a clinical sample, the authors explored the cognitive and clinical correlates of Rorschach color determinants and differences among four affective modulation subtypes: Controlled, Balanced, Under-Controlled, and Flooded. Subtypes were differentiated by measures of affective regulation, reality testing/confusion, and personality traits. Initial support for the relationship of chromatic color response styles and affective modulation was found. PMID:23428172

  20. Explorations in statistics: statistical facets of reproducibility.

    Science.gov (United States)

    Curran-Everett, Douglas

    2016-06-01

    Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This eleventh installment of Explorations in Statistics explores statistical facets of reproducibility. If we obtain an experimental result that is scientifically meaningful and statistically unusual, we would like to know that our result reflects a general biological phenomenon that another researcher could reproduce if (s)he repeated our experiment. But more often than not, we may learn this researcher cannot replicate our result. The National Institutes of Health and the Federation of American Societies for Experimental Biology have created training modules and outlined strategies to help improve the reproducibility of research. These particular approaches are necessary, but they are not sufficient. The principles of hypothesis testing and estimation are inherent to the notion of reproducibility in science. If we want to improve the reproducibility of our research, then we need to rethink how we apply fundamental concepts of statistics to our science. PMID:27231259

  1. An Innovative Context-Based Module to Introduce Students to the Optical Properties of Materials

    Science.gov (United States)

    Testa, I.; Lombardi, S.; Monroy, G.; Sassi, E.

    2011-01-01

    A context-based module to introduce secondary school students to the study of the optical properties of materials and geometric optics is presented. The module implements an innovative teaching approach in which the behaviour of the chosen application, in this article, the optical fibre, is iteratively explored and modelled by means of a…

  2. Retrospect to Human Deep Space Exploration History and Its Prospect in China

    Institute of Scientific and Technical Information of China (English)

    Ye Peijian; Peng Jing

    2006-01-01

    The definition, goal and impacts of deep space exploration are summarized. After a retrospect to past deep exploration activities of human being to date, both recent deep space missions and future missions in 5 years are also listed. There are also brief introductions about the future strategic plans of NASA, ESA,RAKA, JAXA and ISRO. Then authors analyze some important features of global deep space exploration scheme. Key technologies of deep space exploration are also determined. The status of China deep exploration plan is introduced including CE-1 lunar orbiter, the subsequent China Lunar Exploration Program, especially proposal for the second stage of China Lunar Exploration Program, Mars exploration program of China with Russia Kuafu mission, Hard X-Ray Modulated Telescope, Space Solar Telescope. At the end, some suggestions for China future deep space exploration are made.

  3. NASA Robotics for Space Exploration

    Science.gov (United States)

    Fischer, RIchard T.

    2007-01-01

    This presentation focuses on NASA's use of robotics in support of space exploration. The content was taken from public available websites in an effort to minimize any ITAR or EAR issues. The agenda starts with an introduction to NASA and the "Vision for Space Exploration" followed by NASA's major areas of robotic use: Robotic Explorers, Astronaut Assistants, Space Vehicle, Processing, and In-Space Workhorse (space infrastructure). Pictorials and movies of NASA robots in use by the major NASA programs: Space Shuttle, International Space Station, current Solar Systems Exploration and Mars Exploration, and future Lunar Exploration are throughout the presentation.

  4. Exploring the Moon

    CERN Document Server

    Harland, David M

    2008-01-01

    David Harland opens with a review of the robotic probes, namely the Rangers which returned television before crashing into the Moon, the Surveyors which ''soft landed'' in order to investigate the nature of the surface, and the Lunar Orbiters which mapped prospective Apollo landing sites. He then outlines the historic landing by Apollo 11 in terms of what was discovered, and how over the next several missions the program was progressively geared up to enable the final three missions each to spend three days on comprehensive geological investigations. He concludes with a review of the robotic spacecraft that made remote-sensing observations of the Moon. Although aimed at the enthusiast, and can be read as an adventure in exploration, the book develops the scientific theme of lunar geology, and therefore will be of use as background reading for undergraduate students of planetary sciences. In addition, with the prospect of a resumption of human missions, it will help journalists understand what Apollo achieved ...

  5. Nutrition for Space Exploration

    Science.gov (United States)

    Smith, Scott M.

    2005-01-01

    Nutrition has proven to be critical throughout the history of human exploration, on both land and water. The importance of nutrition during long-duration space exploration is no different. Maintaining optimal nutritional status is critical for all bodily systems, especially in light of the fact that that many are also affected by space flight itself. Major systems of concern are bone, muscle, the cardiovascular system, the immune system, protection against radiation damage, and others. The task ahead includes defining the nutritional requirements for space travelers, ensuring adequacy of the food system, and assessing crew nutritional status before, during, and after flight. Accomplishing these tasks will provide significant contributions to ensuring crew health on long-duration missions. In addition, development and testing of nutritional countermeasures to effects of space flight is required, and assessment of the impact of other countermeasures (such as exercise and pharmaceuticals) on nutrition is also critical for maintaining overall crew health. Vitamin D stores of crew members are routinely low after long-duration space flight. This occurs even when crew members take vitamin D supplements, suggesting that vitamin D metabolism may be altered during space flight. Vitamin D is essential for efficient absorption of calcium, and has numerous other benefits for other tissues with vitamin D receptors. Protein is a macronutrient that requires additional study to define the optimal intake for space travelers. Administration of protein to bed rest subjects can effectively mitigate muscle loss associated with disuse, but too much or too little protein can also have negative effects on bone. In another bed rest study, we found that the ratio of protein to potassium was correlated with the level of bone resorption: the higher the ratio, the more bone resorption. These relationships warrant further study to optimize the beneficial effect of protein on both bone and muscle

  6. Exploring Entrepreneurial Network Relationships

    DEFF Research Database (Denmark)

    Norus, Jesper

    2003-01-01

    explores four different strategies for dealing with network relations; the research oriented strategy, the incubator strategy, the industrial partnering strategy, and the policy-oriented strategy. The research-oriented strategy is narrowly focusing on how a biotechnology firm transforms their scientific...... of bringing the technologies from an experimental stage at a research lab to be able handle industrial processes and full-scale production. Last but not least the policy oriented strategy focus on problem of having products approved by the public authorities.Theoretically the article draws upon network...... theories and a dynamic view of network relations. That is done in order to capture the nature of the relationships between different types of actors, but also in order to emphasize the informal nature of some of these relationships.The article has a dual purpose; 1) From a corporate point of view...

  7. Bayesian Adaptive Exploration

    CERN Document Server

    Loredo, T J

    2004-01-01

    I describe a framework for adaptive scientific exploration based on iterating an Observation--Inference--Design cycle that allows adjustment of hypotheses and observing protocols in response to the results of observation on-the-fly, as data are gathered. The framework uses a unified Bayesian methodology for the inference and design stages: Bayesian inference to quantify what we have learned from the available data and predict future data, and Bayesian decision theory to identify which new observations would teach us the most. When the goal of the experiment is simply to make inferences, the framework identifies a computationally efficient iterative ``maximum entropy sampling'' strategy as the optimal strategy in settings where the noise statistics are independent of signal properties. Results of applying the method to two ``toy'' problems with simulated data--measuring the orbit of an extrasolar planet, and locating a hidden one-dimensional object--show the approach can significantly improve observational eff...

  8. Exploring String Theory Backgrounds

    CERN Document Server

    Williams, B P

    2004-01-01

    This thesis examines phenomenological and theoretical questions by exploring string theoretic backgrounds. Part I focuses on cosmology. First we propose that the induced metric along a brane moving through a curved bulk may be interpreted as the cosmology of the brane universe, providing a resolution to the apparent cosmological singularity on the brane. We then look at various decay channels of the certain meta-stable de Sitter vacua and show that there exist NS5-brane meditated decays which are much faster than decays to decompactification. Part II discusses a new class of nongeometric vacua in string theory. These backgrounds may be described locally as T2 fibrations. By enlarging the monodromy group of the fiber to include perturbative stringy duality symmetries we are able to explicitly construct nongeometric backgrounds.

  9. Exploring Oman's Energy Sector

    Science.gov (United States)

    Al-Saqlawi, Juman; Madani, Kaveh; Mac Dowell, Niall

    2016-04-01

    Located in a region where over 40% of the world's oil and gas reserves lie and in a trend similar to that of its neighbors, Oman's economy has been reliant on crude oil export since the 1970's. Being aware of the dangers of this reliance along with the discovery of Natural Gas since the 1980s, the Omani government's policy of diversifying its economy has shifted its reliance on Oil to another fossil fuel, namely Natural Gas. Given that energy is the lifeline of Oman's economy, effective and efficient forward planning and policy development is essential for the country's current and future economic development. This presentation explores the current status of the energy sector in Oman from home production and import to eventual final uses. The presentation highlights the major issues with Oman's current energy policies and suggests various strategies that could be adopted by Oman for a more efficient and sustainable future.

  10. KEEPING Exploring New Frontiers

    Institute of Scientific and Technical Information of China (English)

    Yan Manman

    2010-01-01

    @@ "To live fully is to surge ahead constantly. After achieving what you have aimed at, you should aim higher.Therefore, success doesn't mean what level you are at, but the journey of achieving next level". This is the meaning of success in the eyes of Guy Lam, Chairman of Pacrim International Capital Inc, Over 20 years since he began to engage in business, He has been keeping it in mind that the value of life lies in the journey to new creation but not the level of ownership. Therefore, when he achieved one success after another in different fields, Guy was never content with the achievement he had obtained.but more eager to explore new frontiers.

  11. Ice Giant Exploration

    Science.gov (United States)

    Rymer, A. M.; Arridge, C. S.; Masters, A.; Turtle, E. P.; Simon, A. A.; Hofstadter, M. D.; Turrini, D.; Politi, R.

    2015-12-01

    The Ice Giants in our solar system, Uranus and Neptune, are fundamentally different from their Gas Giant siblings Jupiter and Saturn, from the different proportions of rock and ice to the configuration of their planetary magnetic fields. Kepler space telescope discoveries of exo-planets indicate that planets of this type are among the most ubiquitous universally and therefore a future mission to explore the nature of the Ice Giants in our own solar system will provide insights into the nature of extra-solar system objects in general. Uranus has the smallest self- luminosity of all the planets, potentially related to catastrophic events early in the planet's history, which also may explain Uranus' large obliquity. Uranus' atmosphere is subject to extreme seasonal forcing making it unique in the Solar System. Neptune is also unique in a number of ways, notably its large moon Triton which is likely a captured Kuiper Belt Object and one of only two moons in the solar system with a robustly collisional atmosphere. Similar to Uranus, the angle between the solar wind and the magnetic dipole axis is subject to large-amplitude variations on both diurnal and seasonal timescales, but peculiarly it has one of the quietest magnetospheres of the solar system, at least according to Voyager 2, the only spacecraft to encounter Neptune to date. A comprehensive mission, as advocated in the Decadal Survey, would provide enormous science return but is also challenging and expensive. In this presentation we will discuss mission scenarios and suggest how collaboration between disciplines and internationally can help us to pursue a mission that includes Ice Giant exploration.

  12. Prime Submodules and Flat Modules

    Institute of Scientific and Technical Information of China (English)

    A.AZIZI

    2007-01-01

    In this paper, some characterizations of prime submodules in fiat modules and, particularly,in free modules are given. Furthermore, the height of prime submodules and some saturated chain of prime submodules are also given.

  13. Generic ISIS Transport Module Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of the Generic ISIS Transport Module is to provide a means to bring living specimens to and from orbit. In addition to living specimens, the module can...

  14. Artinianness of local cohomology modules

    Science.gov (United States)

    Aghapournahr, Moharram; Melkersson, Leif

    2014-04-01

    Some uniform theorems on the artinianness of certain local cohomology modules are proven in a general situation. They generalize and imply previous results about the artinianness of some special local cohomology modules in the graded case.

  15. Modulating macrophage response to biomaterials

    Science.gov (United States)

    Zaveri, Toral

    Macrophages recruited to the site of biomaterial implantation are the primary mediators of the chronic foreign body response to implanted materials. Since foreign body response limits performance and functional life of numerous implanted biomaterials/medical devices, various approaches have been investigated to modulate macrophage interactions with biomaterial surfaces to mitigate this response. In this work we have explored two independent approaches to modulate the macrophage inflammatory response to biomaterials. The first approach targets surface integrins, cell surface receptors that mediate cell adhesion to biomaterials through adhesive proteins spontaneously adsorbed on biomaterial surfaces. The second approach involves surface modification of biomaterials using nanotopographic features since nanotopography has been reported to modulate cell adhesion and viability in a cell type-dependent manner. More specifically, Zinc Oxide (ZnO) nanorod surface was investigated for its role in modulating macrophage adhesion and survival in vitro and foreign body response in vivo. For the first approach, we have investigated the role of integrin Mac-1 and RGD-binding integrins in the in-vivo osteolysis response and macrophage inflammatory processes of phagocytosis as well as inflammatory cytokine secretion in response to particulate biomaterials. We have also investigated the in vivo foreign body response (FBR) to subcutaneously implanted biomaterials by evaluating the thickness of fibrous capsule formed around the implants after 2 weeks of implantation. The role of Mac-1 integrin was isolated using a Mac-1 KO mouse and comparing it to a WT control. The role of RGD binding integrins in FBR was investigated by coating the implanted biomaterial with ELVAX(TM) polymer loaded with Echistatin which contains the RGD sequence. For the in-vivo osteolysis study and to study the in-vitro macrophage response to particulate biomaterials, we used the RGD peptide encapsulated in ELVAX

  16. Automation &robotics for future Mars exploration

    Science.gov (United States)

    Schulte, W.; von Richter, A.; Bertrand, R.

    2003-04-01

    Automation and Robotics (A&R) are currently considered as a key technology for Mars exploration. initiatives in this field aim at developing new A&R systems and technologies for planetary surface exploration. Kayser-Threde led the study AROMA (Automation &Robotics for Human Mars Exploration) under ESA contract in order to define a reference architecture of A&R elements in support of a human Mars exploration program. One of the goals was to define new developments and to maintain the competitiveness of European industry within this field. We present a summary of the A&R study in respect to a particular system: The Autonomous Research Island (ARI). In the Mars exploration scenario initially a robotic outpost system lands at pre-selected sites in order to search for life forms and water and to analyze the surface, geology and atmosphere. A&R systems, i.e. rovers and autonomous instrument packages, perform a number of missions with scientific and technology development objectives on the surface of Mars as part of preparations for a human exploration mission. In the Robotic Outpost Phase ARI is conceived as an automated lander which can perform in-situ analysis. It consists of a service module and a micro-rover system for local investigations. Such a system is already under investigation and development in other TRP activities. The micro-rover system provides local mobility for in-situ scientific investigations at a given landing or deployment site. In the long run ARI supports also human Mars missions. An astronaut crew would travel larger distances in a pressurized rover on Mars. Whenever interesting features on the surface are identified, the crew would interrupt the travel and perform local investigations. In order to save crew time ARI could be deployed by the astronauts to perform time-consuming investigations as for example in-situ geochemistry analysis of rocks/soil. Later, the crew could recover the research island for refurbishment and deployment at another

  17. Modulational instability of nematic phase

    Indian Academy of Sciences (India)

    T Mithun; K Porsezian

    2014-02-01

    We numerically observe the effect of homogeneous magnetic field on the modulationally stable case of polar phase in = 2 spinor Bose–Einstein condensates (BECs). Also we investigate the modulational instability of uniaxial and biaxial (BN) states of polar phase. Our observations show that the magnetic field triggers the modulational instability and demonstrate that irrespective of the magnetic field effect the uniaxial and biaxial nematic phases show modulational instability.

  18. On closed weak supplemented modules

    Institute of Scientific and Technical Information of China (English)

    ZENG Qing-yi; SHI Mei-hua

    2006-01-01

    A module M is called closed weak supplemented if for any closed submodule N of M, there is a submodule K of M such that M=K+N and K(c)N<<M. Any direct summand of closed weak supplemented module is also closed weak supplemented.Any nonsingular image of closed weak supplemented module is closed weak supplemented. Nonsingular V-rings in which all nonsingular modules are closed weak supplemented are characterized in Section 4.

  19. Mineral exploration in developing countries

    International Nuclear Information System (INIS)

    The chapter provides an overview and comparisons of mineral exploration in Botswana and Papua New Guinea, including selection comparisons with Australia and Canada. It describes the history of exploration in Botswana and PNG. The concluding section summarizes the findings

  20. Deep Exploration via Bootstrapped DQN

    OpenAIRE

    Osband, Ian; Blundell, Charles; Pritzel, Alexander; Van Roy, Benjamin

    2016-01-01

    Efficient exploration in complex environments remains a major challenge for reinforcement learning. We propose bootstrapped DQN, a simple algorithm that explores in a computationally and statistically efficient manner through use of randomized value functions. Unlike dithering strategies such as epsilon-greedy exploration, bootstrapped DQN carries out temporally-extended (or deep) exploration; this can lead to exponentially faster learning. We demonstrate these benefits in complex stochastic ...

  1. Weighted network modules

    International Nuclear Information System (INIS)

    The inclusion of link weights into the analysis of network properties allows a deeper insight into the (often overlapping) modular structure of real-world webs. We introduce a clustering algorithm clique percolation method with weights (CPMw) for weighted networks based on the concept of percolating k-cliques with high enough intensity. The algorithm allows overlaps between the modules. First, we give detailed analytical and numerical results about the critical point of weighted k-clique percolation on (weighted) Erdos-Renyi graphs. Then, for a scientist collaboration web and a stock correlation graph we compute three-link weight correlations and with the CPMw the weighted modules. After reshuffling link weights in both networks and computing the same quantities for the randomized control graphs as well, we show that groups of three or more strong links prefer to cluster together in both original graphs

  2. Weighted network modules

    Science.gov (United States)

    Farkas, Illés; Ábel, Dániel; Palla, Gergely; Vicsek, Tamás

    2007-06-01

    The inclusion of link weights into the analysis of network properties allows a deeper insight into the (often overlapping) modular structure of real-world webs. We introduce a clustering algorithm clique percolation method with weights (CPMw) for weighted networks based on the concept of percolating k-cliques with high enough intensity. The algorithm allows overlaps between the modules. First, we give detailed analytical and numerical results about the critical point of weighted k-clique percolation on (weighted) Erdos Rényi graphs. Then, for a scientist collaboration web and a stock correlation graph we compute three-link weight correlations and with the CPMw the weighted modules. After reshuffling link weights in both networks and computing the same quantities for the randomized control graphs as well, we show that groups of three or more strong links prefer to cluster together in both original graphs.

  3. NEUROBIOLOGICAL MODULATORS OF ANXIETY

    Directory of Open Access Journals (Sweden)

    Mohale Deepak S.

    2012-01-01

    Full Text Available Anxiety can be a core symptom of various mental/ behavioral disorders such as major depressive disorders, obsessive-compulsive disorders, panic disorder, adaptive disorder, post-traumatic stress disorder, social withdrawal disorder, and various phobias. The neuroanatomic circuits that support fear and anxiety behavior are modulated by a variety of neurochemicals, these include the peptidergic neurotransmitters, Corticotrophin releasing factor (CRF, neuropeptide Y (NPY, and substance P, the monoaminergic transmitters, Norepinephrine (NE, serotonin (5-hydroxytryptamine or 5-HT, and dopamine (DA, and the amino acid transmitters, Gamma Aminobuteric Acid (GABA and glutamate and many more. These neurochemical systems subserve important adaptive functions in preparing the organism for responding to threat or stress, by increasing vigilance, modulating memory, mobilizing energy stores, and elevating cardiovascular function. Nevertheless, these biological responses to threat and stress can become maladaptive if they are chronically or inappropriately activated.

  4. Weighted network modules

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, Illes [Department of Biological Physics, Eoetvoes University, Budapest, H-1117 (Hungary); Abel, Daniel [Department of Biological Physics, Eoetvoes University, Budapest, H-1117 (Hungary); Palla, Gergely [Department of Biological Physics, Eoetvoes University, Budapest, H-1117 (Hungary); Vicsek, Tamas [Department of Biological Physics, Eoetvoes University, Budapest, H-1117 (Hungary)

    2007-06-15

    The inclusion of link weights into the analysis of network properties allows a deeper insight into the (often overlapping) modular structure of real-world webs. We introduce a clustering algorithm clique percolation method with weights (CPMw) for weighted networks based on the concept of percolating k-cliques with high enough intensity. The algorithm allows overlaps between the modules. First, we give detailed analytical and numerical results about the critical point of weighted k-clique percolation on (weighted) Erdos-Renyi graphs. Then, for a scientist collaboration web and a stock correlation graph we compute three-link weight correlations and with the CPMw the weighted modules. After reshuffling link weights in both networks and computing the same quantities for the randomized control graphs as well, we show that groups of three or more strong links prefer to cluster together in both original graphs.

  5. FERMI multi-chip module

    CERN Multimedia

    This FERMI multi-chip module contains five million transistors. 25 000 of these modules will handle the flood of information through parts of the ATLAS and CMS detectors at the LHC. To select interesting events for recording, crucial decisions are taken before the data leaves the detector. FERMI modules are being developed at CERN in partnership with European industry.

  6. Thermal modulation for gas chromatography

    Science.gov (United States)

    Hasselbrink, Ernest F. (Inventor); Libardoni, Mark (Inventor); Stewart, Kristine (Inventor); Waite, J. Hunter (Inventor); Block, Bruce P. (Inventor); Sacks, Richard D. (Inventor)

    2007-01-01

    A thermal modulator device for gas chromatography and associated methods. The thermal modulator device includes a recirculating fluid cooling member, an electrically conductive capillary in direct thermal contact with the cooling member, and a power supply electrically coupled to the capillary and operable for controlled resistive heating of the capillary. The capillary can include more than one separate thermally modulated sections.

  7. Higher Level Orderings on Modules

    Institute of Scientific and Technical Information of China (English)

    Min WU; Guang Xing ZENG

    2005-01-01

    The aim of this paper is to investigate higher level orderings on modules over commutative rings. On the basis of the theory of higher level orderings on fields and commutative rings, some results involving existence of higher level orderings are generalized to the category of modules over commutative rings. Moreover, a strict intersection theorem for higher level orderings on modules is established.

  8. Physics. Module 1. Mechanics

    OpenAIRE

    Бовтрук, Алла Георгіївна; Мєняйлов, Сергій Миколайович; Максимов, Сергій Леонідович; Поліщук, Аркадій Петрович

    2009-01-01

    Ukraine’s joining Bologna process requires creating new books in physics (in English in particular). The book is developed for all forms of studying physics on the Credit-based Modular System basis in higher school. «Physics. Module 1. Mechanics» presents Newtonian mechanics and Special theory of relativity. It contains eight Study Units which include theoretical information, test questions, sample problems, laboratory works and individual home tasks. It is designed for students of engi...

  9. Chemical release module facility

    Science.gov (United States)

    Reasoner, D. L.

    1980-01-01

    The chemical release module provides the capability to conduct: (1) thermite based metal vapor releases; (2) pressurized gas releases; (3) dispersed liquid releases; (4) shaped charge releases from ejected submodules; and (5) diagnostic measurements with pi supplied instruments. It also provides a basic R-F and electrical system for: (1) receiving and executing commands; (2) telemetering housekeeping data; (3) tracking; (4) monitoring housekeeping and control units; and (5) ultrasafe disarming and control monitoring.

  10. Digital CAMAC modules

    International Nuclear Information System (INIS)

    Data sheets and block diagrams of new CAMAC modules are presented. These consist of a RS232C serial interface, a crate controller for the personnel computer IBM PC/AT, a 24-bit word to 16-bit word converter, a 4K of 16-bit words buffer memory, an input register for ECL logical level signals, a tester for the type A1 crate controllers and a multichannel analyzer tester. 15 refs.; 8 figs.; 1 tab

  11. Weighted network modules

    OpenAIRE

    Farkas, Illes J.; Abel, Daniel; Palla, Gergely; Vicsek, Tamas

    2007-01-01

    The inclusion of link weights into the analysis of network properties allows a deeper insight into the (often overlapping) modular structure of real-world webs. We introduce a clustering algorithm (CPMw, Clique Percolation Method with weights) for weighted networks based on the concept of percolating k-cliques with high enough intensity. The algorithm allows overlaps between the modules. First, we give detailed analytical and numerical results about the critical point of weighted k-clique per...

  12. Modulating aging and longevity

    DEFF Research Database (Denmark)

    Rattan, Suresh

    Provides information and an evaluation of a variety of approaches tried for modulating aging and longevity, including dietary supplementation with antioxidants, vitamins and hormones, genetic engineering, life-style alterations, and hormesis through mild stress. After decades of systematic...... mild stress. The goal of research on ageing is not to increase human longevity regardless of the consequences, but to increase active longevity free from disability and functional dependence...

  13. Adaptive modulations of martensites

    Czech Academy of Sciences Publication Activity Database

    Kaufmann, S.; Roßler, U.K.; Heczko, Oleg; Wuttig, M.; Buschbeck, J.; Schultz, L.; Fähler, S.

    2010-01-01

    Roč. 104, č. 14 (2010), 145702/1-145702/4. ISSN 0031-9007 Institutional research plan: CEZ:AV0Z10100520 Keywords : adaptive concept of modulated martensite * martensitic Ni-Mn-Ga films * austenite * 14M martensite Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 7.621, year: 2010 http://link.aps.org/doi/10.1103/PhysRevLett.104.145702

  14. COMBINING MODULES FOR MOVEMENT

    OpenAIRE

    Bizzi, E; Cheung, V.C.K.; d’Avella, A.; Saltiel, P.; Tresch, M.

    2007-01-01

    We review experiments supporting the hypothesis that the vertebrate motor system produces movements by combining a small number of units of motor output. Using a variety of approaches such as microstimulation of the spinal cord, NMDA iontophoresis, and an examination of natural behaviors in intact and deafferented animals we have provided evidence for a modular organization of the spinal cord. A module is a functional unit in the spinal cord that generates a specific motor output by imposing ...

  15. Explorations in Statistics: Permutation Methods

    Science.gov (United States)

    Curran-Everett, Douglas

    2012-01-01

    Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This eighth installment of "Explorations in Statistics" explores permutation methods, empiric procedures we can use to assess an experimental result--to test a null hypothesis--when we are reluctant to trust statistical…

  16. Explorations in Statistics: the Bootstrap

    Science.gov (United States)

    Curran-Everett, Douglas

    2009-01-01

    Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This fourth installment of Explorations in Statistics explores the bootstrap. The bootstrap gives us an empirical approach to estimate the theoretical variability among possible values of a sample statistic such as the…

  17. The CDF TESTCLK module - Providing system level clocking and triggering for Run 2 prototyping crates

    International Nuclear Information System (INIS)

    The TESTCLK module was specifically designed for use in prototyping crates for the Colliding Detector Facility (CDF) Run 2 Experiment at Fermi National Accelerator Laboratory. The TESTCLK Module allows the user to supply system clocks and trigger signals to stand-alone crates. This module has allowed designers of the CDF Run 2 electronics to thoroughly test their modules, despite the lack of a DAQ system supplied clock and trigger interface. This paper will explore the features that were found important to incorporate into the TESTCLK, and describe how they were implemented. The paper will also describe how the TESTCLK module has been used to support the initial implementation of the DAQ system at CDF. This has allowed data taking and testing of CDF Electronic modules before production clock and trigger modules became available

  18. Modulated reheating by curvaton

    CERN Document Server

    Choi, Ki-Young

    2012-01-01

    There might be a light scalar field during inflation which is not responsible for the accelerating inflationary expansion. Then, its quantum fluctuation is stretched during inflation. This scalar field could be a curvaton, if it decays at a late time. In addition, if the inflaton decay rate depends on the light scalar field expectation value by interactions between them, density perturbations could be generated by the quantum fluctuation of the light field when the inflaton decays. This is modulated reheating mechanism. We study curvature perturbation in models where a light scalar field does not only play a role of curvaton but also induce modulated reheating at the inflaton decay. We calculate the non-linearity parameters as well as the scalar spectral index and the tensor-to-scalar ratio. We find that there is a parameter region where non-linearity parameters are also significantly enhanced by the cancellation between the modulated effect and the curvaton contribution. For the simple quadratic potential mo...

  19. Solar Module Fabrication

    Directory of Open Access Journals (Sweden)

    A. El Amrani

    2007-04-01

    Full Text Available One of the most important steps in the photovoltaic industry is the encapsulation of the solar cells. It consists to connect the cells in order to provide useful power for any application and also protect them from environmental damages which cause corrosion, and mechanical shocks. In this paper, we present the encapsulation process we have developed at Silicon Technology Unit (UDTS for monocrystalline silicon solar cells. We will focus particularly on the thermal treatment, the most critical step in the process, which decides on the quality and the reliability of the module. This thermal treatment is conducted in two steps: the lamination and the polymerization. Several tests of EVA reticulation have been necessary for setting technological parameters such as the level of vacuum, the pressure, the temperature, and the time. The quality of our process has been confirmed by the tests conducted on our modules at the European Laboratory of Joint Research Centre (JRC of ISPRA (Italy. The electrical characterization of the modules has showed that after the encapsulation the current has been improved by a factor of 4% to 6% and the power gain by a factor of 4% to 7%. This is mainly due to the fact of using a treated glass, which reduces the reflection of the light at a level as low as 8%.

  20. Allosteric modulation of caspases.

    Science.gov (United States)

    Häcker, Hans-Georg; Sisay, Mihiret Tekeste; Gütschow, Michael

    2011-11-01

    Caspases are proteolytic enzymes mainly involved in the induction and execution phases of apoptosis. This type of programmed cell death is an essential regulatory process required to maintain the integrity and homeostasis of multicellular organisms. Inappropriate apoptosis is attributed a key role in many human diseases, including neurodegenerative disorders, ischemic damage, autoimmune diseases and cancer. Allosteric modulation of the function of a protein occurs when the regulatory trigger, such as the binding of a small effector or inhibitor molecule, takes place some distance from the protein's active site. In recent years, several caspases have been identified that possess allosteric sites and binding of small molecule to these sites resulted in the modulation of enzyme activities. Regulation of caspase activity by small molecule allosteric modulators is believed to be of great therapeutic importance. In this review we give brief highlights on recent developments in identifying and characterizing natural and synthetic allosteric inhibitors as well as activators of caspases and discuss their potential in drug discovery and protein engineering. PMID:21807025

  1. Psychopathic traits affect the visual exploration of facial expressions.

    Science.gov (United States)

    Boll, Sabrina; Gamer, Matthias

    2016-05-01

    Deficits in emotional reactivity and recognition have been reported in psychopathy. Impaired attention to the eyes along with amygdala malfunctions may underlie these problems. Here, we investigated how different facets of psychopathy modulate the visual exploration of facial expressions by assessing personality traits in a sample of healthy young adults using an eye-tracking based face perception task. Fearless Dominance (the interpersonal-emotional facet of psychopathy) and Coldheartedness scores predicted reduced face exploration consistent with findings on lowered emotional reactivity in psychopathy. Moreover, participants high on the social deviance facet of psychopathy ('Self-Centered Impulsivity') showed a reduced bias to shift attention towards the eyes. Our data suggest that facets of psychopathy modulate face processing in healthy individuals and reveal possible attentional mechanisms which might be responsible for the severe impairments of social perception and behavior observed in psychopathy. PMID:27016126

  2. Uranium exploration in Ethiopia

    International Nuclear Information System (INIS)

    Full text: Radioactive exploration dates back to 1955 and since then little progress has been made. Few pits and trenches in some places show radioactive anomalies.The Wadera radioactive anomaly occurs within the lower part of Wadera series, Southern Ethiopia. As observed from a trench the anomalous bed has a thickness of 0.9-1.2 m and is made of reddish-grey thin bedded sandstones.The presence of Xenotime in arkosic sandstone points to the sedimentary origin of mineralization. It was noticed that the sandstone in the lower part of Wadera series has at places a radioactivity 2-3 times higher than adjacent gneisses. The presence of a placer of such a type in the Wadera series is probably a clue for the existence of larger deposits in the area. In 2007 geological, geochemical and geophysical surveys were conducted to identify and delineate Uranium mineralization in three localities(Kuro, Kalido and Gueti) of Werri area, southern Ethiopia. Kaolinization, silicification, epidotization and chloritization are the main types of alteration associated with different units in the area. Uranium-bearing grains which are hosted in pegmatite veins and associated with magnetite/or ilmenite were observed in the three localities. Geochemical exploration accompanied by geological mapping and radiometric survey was done by employing heavy mineral concentrate, soil, chip and trench channel sampling. Radiometric readings of total count, U,Th and K were taken using GAD-6.Soil and trench geochemical samples of the localities analyzed by ICP-MS have shown 0.1 to 3.8 ppm and 3.9 to 147 ppm Uranium and 3.5 to 104.7 ppm and 3.9 to 147ppm Thorium respectively. Radiometric reading is higher in pegmatite veins that host Uranium-bearing minerals and some course grained pegmatoidal granite varieties. The areas recognized for Uranium associations need further investigations using state-of-the-art to discover economic deposits for development and utilization of the resource. (author)

  3. Control of Foxp3 stability through modulation of TET activity.

    Science.gov (United States)

    Yue, Xiaojing; Trifari, Sara; Äijö, Tarmo; Tsagaratou, Ageliki; Pastor, William A; Zepeda-Martínez, Jorge A; Lio, Chan-Wang J; Li, Xiang; Huang, Yun; Vijayanand, Pandurangan; Lähdesmäki, Harri; Rao, Anjana

    2016-03-01

    Ten-eleven translocation (TET) enzymes oxidize 5-methylcytosine (5mC) to 5-hydroxymethylcytosine and other oxidized methylcytosines, intermediates in DNA demethylation. In this study, we examine the role of TET proteins in regulating Foxp3, a transcription factor essential for the development and function of regulatory T cells (T reg cells), a distinct lineage of CD4(+) T cells that prevent autoimmunity and maintain immune homeostasis. We show that during T reg cell development in the thymus, TET proteins mediate the loss of 5mC in T reg cell-specific hypomethylated regions, including CNS1 and CNS2, intronic cis-regulatory elements in the Foxp3 locus. Similar to CNS2-deficient T reg cells, the stability of Foxp3 expression is markedly compromised in T reg cells from Tet2/Tet3 double-deficient mice. Vitamin C potentiates TET activity and acts through Tet2/Tet3 to increase the stability of Foxp3 expression in TGF-β-induced T reg cells. Our data suggest that targeting TET enzymes with small molecule activators such as vitamin C might increase induced T reg cell efficacy. PMID:26903244

  4. Receiver Gain Modulation Circuit

    Science.gov (United States)

    Jones, Hollis; Racette, Paul; Walker, David; Gu, Dazhen

    2011-01-01

    A receiver gain modulation circuit (RGMC) was developed that modulates the power gain of the output of a radiometer receiver with a test signal. As the radiometer receiver switches between calibration noise references, the test signal is mixed with the calibrated noise and thus produces an ensemble set of measurements from which ensemble statistical analysis can be used to extract statistical information about the test signal. The RGMC is an enabling technology of the ensemble detector. As a key component for achieving ensemble detection and analysis, the RGMC has broad aeronautical and space applications. The RGMC can be used to test and develop new calibration algorithms, for example, to detect gain anomalies, and/or correct for slow drifts that affect climate-quality measurements over an accelerated time scale. A generalized approach to analyzing radiometer system designs yields a mathematical treatment of noise reference measurements in calibration algorithms. By treating the measurements from the different noise references as ensemble samples of the receiver state, i.e. receiver gain, a quantitative description of the non-stationary properties of the underlying receiver fluctuations can be derived. Excellent agreement has been obtained between model calculations and radiometric measurements. The mathematical formulation is equivalent to modulating the gain of a stable receiver with an externally generated signal and is the basis for ensemble detection and analysis (EDA). The concept of generating ensemble data sets using an ensemble detector is similar to the ensemble data sets generated as part of ensemble empirical mode decomposition (EEMD) with exception of a key distinguishing factor. EEMD adds noise to the signal under study whereas EDA mixes the signal with calibrated noise. It is mixing with calibrated noise that permits the measurement of temporal-functional variability of uncertainty in the underlying process. The RGMC permits the evaluation of EDA by

  5. Endogenous strategy in exploration.

    Science.gov (United States)

    Solman, Grayden J F; Kingstone, Alan

    2015-12-01

    We examined the characteristics of endogenous exploratory behaviors in a generalized search task in which guidance signals (e.g., landmarks, semantics, visual saliency, layout) were limited or precluded. Individuals looked for the highest valued cell in an array and were scored on the quality of the best value they could find. Exploration was guided only by the cells that had been previously examined, and the value of this guidance was manipulated by adjusting spatial autocorrelation to produce relatively smooth and rough landscapes-that is, arrays in which nearby cells had unrelated values (low correlation = rough) or similar values (high correlation = smooth). For search in increasingly rough as compared with smooth arrays, we found reduced performance despite increased sampling and increased time spent searching after revelation of a searcher's best cell. Spatially, sampling strategies tended toward more excursive, branching, and space-filling patterns as correlation decreased. Using a novel generalized-recurrence analysis, we report that these patterns reflect an increase in systematic search paths, characterized by regularized sweeps with localized infilling. These tendencies were likewise enhanced for high-performance as compared with low-performance participants. The results suggest a trade-off between guidance (in smooth arrays) and systematicity (in rough arrays), and they provide insight into the particular strategic approaches adopted by searchers when exogenous guiding information is minimized. PMID:26214501

  6. International Ultraviolet Explorer (IUE)

    Science.gov (United States)

    Boehm, Karl-Heinz

    1992-01-01

    The observation, data reduction, and interpretation of ultraviolet spectra (obtained with the International Ultraviolet Explorer) of Herbig-Haro objects, stellar jets, and (in a few cases) reflection nebulae in star-forming regions is discussed. Intermediate results have been reported in the required semi-annual reports. The observations for this research were obtained in 23 (US1) IUE shifts. The spectra were taken in the low resolution mode with the large aperture. The following topics were investigated: (1) detection of UV spectra of high excitation Herbig-Haro (HH) objects, identification of emission lines, and a preliminary study of the energy distribution of the ultraviolet continuum; (2) details of the continuum energy distribution of these spectra and their possible interpretation; (3) the properties of the reddening (extinction) of HH objects; (4) the possible time variation of strong emission lines in high excitation HH objects; (5) the ultraviolet emission of low excitation HH objects, especially in the fluorescent lines of the H2 molecule; (6) the ultraviolet emission in the peculiar object HH24; (7) the spatial emission distribution of different lines and different parts of the continuum in different HH objects; and (8) some properties of reflection nebula, in the environment of Herbig-Haro objects. Each topic is discussed.

  7. Dynamics Explorer guest investigator

    Science.gov (United States)

    Sojka, Jan J.

    1991-01-01

    A data base of satellite particle, electric field, image, and plasma data was used to determine correlations between the fields and the particle auroral boundaries. A data base of 8 days of excellent coverage from all instruments was completed. The geomagnetic conditions associated with each of the selected data periods, the number of UV image passes per study day that were obtained, and the total number of UV images for each day are given in tabular form. For each of the days listed in Table 1, both Vector Electric Field Instrument (VEFI) electric potential data and LAPI integrated particle energy fluxes were obtained. On the average, between 8 and 11 passes of useful data per day were obtained. These data are displayed in a format such that either the statistical electric field model potential or the statistical precipitation energy flux could be superimposed. The Heppner and Maynard (1987) and Hardy et al. (1987) models were used for the electric potential and precipitation, respectively. In addition, the auroral image intensity along the Dynamics Explorer-2 satellite pass could be computed and plotted along with the LAPI precipitation data and Hardy et al. (1987) values.

  8. Human Space Exploration

    Science.gov (United States)

    Jeevarajan, Antony

    2014-01-01

    The Mars probe, launched by India a few months ago, is on its way to Mars. At this juncture, it is appropriate to talk about the opportunities presented to us for the Human Exploration of Mars. I am planning to highlight some of the challenges to take humans to Mars, descend, land, stay, ascend and return home safely. The logistics of carrying the necessary accessories to stay at Mars will be delivered in multiple stages using robotic missions. The primary ingredients for human survival is air, water, food and shelter and the necessity to recycle the primary ingredients will be articulated. Humans have to travel beyond the van Allen radiation belt under microgravity condition during this inter-planetary travel for about 6 months minimum one way. The deconditioning of human system under microgravity conditions and protection of humans from Galactic cosmic radiation during the travel should be taken into consideration. The multi-disciplinary effort to keep the humans safe and functional during this journey will be addressed.

  9. Exploring the dusty Universe

    Directory of Open Access Journals (Sweden)

    Borghese, F

    2005-11-01

    Full Text Available Dust is an ubiquitous inhabitant of the interstellar medium, and leaves an unmistakable signature in its optical properties, and physico-chemical evolution. Although there is little direct knowledge of the true nature of interstellar dust grains, strong evidences point toward the possibility that such grains are composites of many small monomers (mainly made of silicates and carbonaceous materials. We consider two different models of fluffy dust aggregates, occurring as result of ballistic particle-cluster and cluster-cluster aggregation, and a cluster with a Gaussian-like sphere size distribution. We study the optical properties of such composite structures through the multipole fields and the Transition Matrix approach. Our results show the severe limits of applicability of the effective medium theories. By comparing radiation and gravitational forces, we also infer some relevant insights into the dynamical evolution of composite grains in the Solar System. We finally explore the possible role of composite fluffy dust grains in igniting an extraterrestrial prebiotic chemistry.

  10. Using creative writing to explore facilitation skills in practice

    OpenAIRE

    Ann Price; Kathrin Hirter; Clare Lippiatt; Kerry O’Neill

    2016-01-01

    Background: Facilitation skills are key to the effective use of practice development strategies. Students on a masters degree in practice development and innovation undertake a module on facilitation skills that incorporates the use of a creative writing piece to explore facilitation. The aim of this article is to critically reflect on the use of creative writing within an assignment from the lecturer’s perspective. Critical reflection: The Rolfe et al. (2001) model of reflection will be ...

  11. Heart rate variability: a tool to explore the sleeping brain?

    OpenAIRE

    Chouchou, Florian; Desseilles, Martin

    2014-01-01

    Sleep is divided into two main sleep stages: (1) non-rapid eye movement sleep (non-REMS), characterized among others by reduced global brain activity; and (2) rapid eye movement sleep (REMS), characterized by global brain activity similar to that of wakefulness. Results of heart rate variability (HRV) analysis, which is widely used to explore autonomic modulation, have revealed higher parasympathetic tone during normal non-REMS and a shift toward sympathetic predominance during normal REMS. M...

  12. Irrelevant tactile stimulation biases visual exploration in external coordinates

    OpenAIRE

    Ossandón, José P.; Peter König; Tobias Heed

    2015-01-01

    We evaluated the effect of irrelevant tactile stimulation on humans’ free-viewing behavior during the exploration of complex static scenes. Specifically, we address the questions of (1) whether task-irrelevant tactile stimulation presented to subjects’ hands can guide visual selection during free viewing; (2) whether tactile stimulation can modulate visual exploratory biases that are independent of image content and task goals; and (3) in which reference frame these effects occur. Tactile sti...

  13. The Primordial Inflation Polarization Explorer (PIPER)

    Science.gov (United States)

    Lazear, Justin Scott; Ade, Peter A.; Benford, Dominic J.; Bennett, Charles L.; Chuss, David T.; Dotson, Jessie L.; Eimer, Joseph R.; Fixsen, Dale J.; Halpern, Mark; Hinderks, James; Hinshaw, Gary F.; Irwin, Kent; Jhabvala, Christine; Johnson, Bradley; Kogut, Alan; Lowe, Luke; McMahon, Jeff J.; Miller, Timothy M.; Mirel, Paul; Moseley, S. Harvey; Rodriguez, Samelys; Staguhn, Johannes G.; Switzer, Eric R.; Tucker, Carole E.; Weston, Amy; Wollack, Edward

    2014-01-01

    The Primordial Inflation Polarization ExploreR (Piper) is a balloon-borne cosmic microwave background (CMB) polarimeter designed to search for evidence of inflation by measuring the large-angular scale CMB polarization signal. Bicep2 recently reported a detection of B-mode power corresponding to the tensor-to-scalar ratio r = 0.2 on approximately 2 degree scales. If the Bicep2 signal is caused by inflationary gravitational waves (IGWs), then there should be a corresponding increase in B-mode power on angular scales larger than 18 degrees. Piper is currently the only suborbital instrument capable of fully testing and extending the Bicep2 results by measuring the B-mode power spectrum on angular scales theta ? = approximately 0.6 deg to 90 deg, covering both the reionization bump and recombination peak, with sensitivity to measure the tensor-to-scalar ratio down to r = 0.007, and four frequency bands to distinguish foregrounds. Piper will accomplish this by mapping 85% of the sky in four frequency bands (200, 270, 350, 600 GHz) over a series of 8 conventional balloon flights from the northern and southern hemispheres. The instrument has background-limited sensitivity provided by fully cryogenic (1.5 K) optics focusing the sky signal onto four 32×40-pixel arrays of time-domain multiplexed Transition-Edge Sensor (TES) bolometers held at 140 milli-Kelvin. Polarization sensitivity and systematic control are provided by front-end Variabledelay Polarization Modulators (VPMs), which rapidly modulate only the polarized sky signal at 3 Hz and allow Piper to instantaneously measure the full Stokes vector (I,Q,U,0V) for each pointing. We describe the Piper instrument and progress towards its first flight.

  14. Planetary Exploration Panel PEX: Support for lunar exploration

    Science.gov (United States)

    Ehrenfreund, Pascale

    2010-05-01

    The new era of space exploration will be international, human-centric, transdisciplinary and participatory. It will also provide an opportunity to inspire, motivate, and involve an ever increasing number of countries. The objective of the COSPAR Panel on Space Exploration (PEX) is to provide the best, independent, input to support the development of worldwide space exploration programs and to safeguard the scientific assets of solar system objects. The input will be drawn from expertise provided via the contacts maintained by COSPAR's various Associates within the international community and scientific entities. For lunar exploration, the International Lunar Exploration Working Group (ILEWG) and the Lunar Exploration Analysis Group (LEAG), as well as other committees, represent important foci for an even broader base of expertise. Seven NASA Lunar Science Institute nodes are actively supporting space exploration in the US. In addition, the International Space Exploration Coordination group ISECG was established to implement the Global Exploration Strategy GES, contained in a document that was elaborated by representatives of 14 space agencies. PEX provides synergies of existing documents and roadmaps of each of these bodies to support existing space exploration groups, foster transnational alliances and support joint research and education.

  15. Habitat Concepts for Deep Space Exploration

    Science.gov (United States)

    Smitherman, David; Griffin, Brand N.

    2014-01-01

    Future missions under consideration requiring human habitation beyond the International Space Station (ISS) include deep space habitats in the lunar vicinity to support asteroid retrieval missions, human and robotic lunar missions, satellite servicing, and Mars vehicle servicing missions. Habitat designs are also under consideration for missions beyond the Earth-Moon system, including transfers to near-Earth asteroids and Mars orbital destinations. A variety of habitat layouts have been considered, including those derived from the existing ISS designs and those that could be fabricated from the Space Launch System (SLS) propellant tanks. This paper presents a comparison showing several options for asteroid, lunar, and Mars mission habitats using ISS derived and SLS derived modules and identifies some of the advantages and disadvantages inherent in each. Key findings indicate that the larger SLS diameter modules offer built-in compatibility with the launch vehicle, single launch capability without on-orbit assembly, improved radiation protection, lighter structures per unit volume, and sufficient volume to accommodate consumables for long duration missions without resupply. The information provided with the findings includes mass and volume comparison data that should be helpful to future exploration mission planning efforts.

  16. Bent Electro-Absorption Modulator

    DEFF Research Database (Denmark)

    2002-01-01

    The present invention relates to a method and a device for modulating optical signals based on modulating bending losses in bend, quantum well semiconductor waveguide sections. The complex refractive index of the optical active semiconducting components of the waveguide section is modulated by...... applying a variable electric or electronmagnetic field. The modulation of the complex refractive index results in a modulation of the refractive index contrast and the absorption coefficient for the waveguide at the frequency of the light. By carefully adjusting the composition of the semiconducting...... components and the applied electric field in relation to the frequency of the modulated radiation, the bending losses (and possibly coupling losses) will provide extinction of light guided by the bent waveguide section. The refractive index contract may be modulated while keeping the absorption coefficient...

  17. Extension closure of relative syzygy modules

    Institute of Scientific and Technical Information of China (English)

    黄兆泳

    2003-01-01

    In this paper we introduce the notion of relative syzygy modules. We then study the extensionclosure of the category of modules consisting of relative syzygy modules (resp. relative k-torsionfree modules).

  18. Studying Sciences through the Integrated Science Modules

    Directory of Open Access Journals (Sweden)

    Radu Lucian Oltean

    2014-10-01

    Full Text Available In order to stimulate students’ interest for Science study, an active learning Science method of teaching was implemented, making the transition to the model based on exploration and investigation. The “PROFILES – Education through Sciences” training program oriented to improve teaching activities was organized in the frame of European Project “PROFILES – Professional Reflection-Oriented Focus on Inquiry-based Learning and Education through Science” (code: 5.2.2.1-SiS-2010-2.2.1-266589. The general objective of the training program consisted on forming and developing specificcompetences of Science teachers in order to develop an educational process based on scientific inquiry and integrated approach of the Sciences curriculum. Teachers have created Integrated Science Modules that were implemented in the classroom as an active learning Science method.The present paper aims to emphasize the students’ feedback after the implementation of Integrated Science Modules in the classroom. The study is focused on students’ perception of Science topics related with everyday life and importance for thesociety.Keywords: Integrated Science Modules, Profiles Project, CPD Programme.

  19. Exploring oxidative modifications of tyrosine

    DEFF Research Database (Denmark)

    Houée-Lévin, C; Bobrowski, K; Horakova, L;

    2015-01-01

    Protein oxidation is increasingly recognised as an important modulator of biochemical pathways controlling both physiological and pathological processes. While much attention has focused on cysteine modifications in reversible redox signalling, there is increasing evidence that other protein resi...

  20. Spatial light modulation based on photoinduced change in the complex refractive index of bacteriorhodopsin

    Science.gov (United States)

    Takei, Hiroyuki; Shimizu, Norio

    1996-04-01

    Bacteriorhodopsin exhibits photoinduced changes in both absorption and refractive index at 633 nm. To explore the possibility of exploiting this property in constructing a photoaddressed spatial light modulator, we investigated the transmission property of a Fabry-Perot interferometer containing a bacteriorhodopsin thin film. Film was formed that had a phase shift of pi /4 and sufficient interference fringe contrast for spatial light modulation. This establishes the possibility of constructing a spatial light modulator that features nonlinear input-output characteristics and can operate at moderate light intensities of the order of tens of milliwatts per centimeter square. spatial light modulation, complex refractive index.

  1. Modulation of whistlers

    Science.gov (United States)

    Sivokon', V. P.; Bogdanov, V. V.; Druzhin, G. I.; Cherneva, N. V.; Kubyshkin, A. V.; Sannikov, D. V.; Agranat, I. V.

    2014-11-01

    Analysis of the experimental data obtained at Paratunka observatory (53.02° N, 158.65° E; L = 2.3) has revealed a nonstandard form of whistlers involving spectral lines that are symmetric with respect to the whistler. We have shown that this form is most likely due to the amplitude modulation of whistlers by electromagnetic pulses with a length of around 1 s and carrier frequency of around 1.1 kHz. We have suggested that these pulses could be emitted by the auroral electrojet modified by heating radiation from the HAARP facility (62.30° N, 145.30° W; L > 4.2).

  2. A photoelectrical module

    Energy Technology Data Exchange (ETDEWEB)

    Zhukov, K.V.; Nevezhin, O.A.; Rosstokinskiy, V.V.; Ryabikov, S.V.; Strebkov, D.S.; Tveryanovich, E.V.

    1983-01-01

    The photoelectric module, which contains an optical element with trapezoidal transverse cross section, whose lateral facets reflect radiation and different sized bases serve as the facets for input and output of radiation, and photoconverters installed in contact with the output facet, is distinguished by the fact that in order to increase the specific power, the optical element is made of a material transparent to solar radiation in the form of a prism of full internal reflection, where the lesser base of the optical element serves as the output facet for the radiation.

  3. How bees distinguish patterns by green and blue modulation

    Directory of Open Access Journals (Sweden)

    Horridge A

    2015-10-01

    Full Text Available Adrian Horridge Biological Sciences, Australian National University, Canberra, ACT, Australia Abstract: In the 1920s, Mathilde Hertz found that trained bees discriminated between shapes or patterns of similar size by something related to total length of contrasting contours. This input is now interpreted as modulation in green and blue receptor channels as flying bees scan in the horizontal plane. Modulation is defined as total contrast irrespective of sign multiplied by length of edge displaying that contrast, projected to vertical, therefore, combining structure and contrast in a single input. Contrast is outside the eye; modulation is a phasic response in receptor pathways inside. In recent experiments, bees trained to distinguish color detected, located, and measured three independent inputs and the angles between them. They are the tonic response of the blue receptor pathway and modulation of small-field green or (less preferred blue receptor pathways. Green and blue channels interacted intimately at a peripheral level. This study explores in more detail how various patterns are discriminated by these cues. The direction of contrast at a boundary was not detected. Instead, bees located and measured total modulation generated by horizontal scanning of contrasts, irrespective of pattern. They also located the positions of isolated vertical edges relative to other landmarks and distinguished the angular widths between vertical edges by green or blue modulation alone. The preferred inputs were the strongest green modulation signal and angular width between outside edges, irrespective of color. In the absence of green modulation, the remaining cue was a measure and location of blue modulation at edges. In the presence of green modulation, blue modulation was inhibited. Black/white patterns were distinguished by the same inputs in blue and green receptor channels. Left–right polarity and mirror images could be discriminated by retinotopic green

  4. The Primordial Inflation Polarization Explorer (PIPER)

    CERN Document Server

    Gandilo, Natalie N; Benford, Dominic; Bennett, Charles L; Chuss, David T; Dotson, Jessie L; Eimer, Joseph R; Fixsen, Dale J; Halpern, Mark; Hilton, Gene; Hinshaw, Gary F; Irwin, Kent; Jhabvala, Christine; Kimball, Mark; Kogut, Alan; Lowe, Luke; McMahon, Jeff J; Miller, Timothy M; Mirel, Paul; Moseley, S Harvey; Pawlyk, Samuel; Rodriguez, Samelys; Sharp, Elmer; Shirron, Peter; Staguhn, Johannes G; Sullivan, Dan F; Switzer, Eric R; Taraschi, Peter; Tucker, Carole E; Wollack, Edward J

    2016-01-01

    The Primordial Inflation Polarization ExploreR (PIPER) is a balloon-borne telescope designed to measure the polarization of the Cosmic Microwave Background on large angular scales. PIPER will map 85% of the sky at 200, 270, 350, and 600 GHz over a series of 8 conventional balloon flights from the northern and southern hemispheres. The first science flight will use two 32x40 arrays of backshort-under-grid transition edge sensors, multiplexed in the time domain, and maintained at 100 mK by a Continuous Adiabatic Demagnetization Refrigerator. Front-end cryogenic Variable-delay Polarization Modulators provide systematic control by rotating linear to circular polarization at 3 Hz. Twin telescopes allow PIPER to measure Stokes I, Q, U, and V simultaneously. The telescope is maintained at 1.5 K in an LHe bucket dewar. Cold optics and the lack of a warm window permit sensitivity at the sky-background limit. The ultimate science target is a limit on the tensor-to-scalar ratio of r ~ 0.007, from the reionization bump t...

  5. Interactive online optics modules for the college physics course

    Science.gov (United States)

    Hoeling, Barbara M.

    2012-04-01

    A new learning tool for geometrical optics is presented which has been developed for an algebra based introductory college physics course for life science majors. The interactive online learning module contains images, videos of problem solutions, short animated videos, and interactive animations, which allow students to actively explore the physics content beyond the pictures in a textbook. These elements are accompanied by narration and a transcript to guide the students while allowing them to navigate freely between the different parts of the module. The results of student learning, a comparison with a control group, and a survey of student attitudes toward this new instruction method are discussed.

  6. Cell asymmetry correction for temperature modulated differential scanning calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Ishikiriyama, K.; Wunderlich, B. [Tennessee Univ., Knoxville, TN (United States). Dept. of Chemistry]|[Oak Ridge National Lab., TN (United States)

    1996-12-31

    The quality of measurement of heat capacity by differential scanning calorimetry (DSC) is based on strict symmetry of the twin calorimeter, which is important for temperature-modulated DSC. Heat capacities for sapphire-filled and empty aluminium calorimeters (pans) under designed cell imbalance caused by different pan-masses were measured. In addition, positive and negative signs of asymmetry were explored by analyzing the phase-shift between temperature and heat flow for sapphire and empty runs. The phase shifts change by more than 18{degree} depending on asymmetry sign. Once the asymmetry sign is determined, the asymmetry correction for modulated DSC can be made.

  7. Mineral exploration in South Africa

    International Nuclear Information System (INIS)

    While the level of mineral exploration in much of Africa over the last ten to fifteen years has stagnated or declines, it has risen dramatically in South Africa. This chapter reviews this growth trend along with changes in the type of minerals sought through these exploration expenditures, and then identifies factors important to these shifts over time in the level and distribution of exploration expenditures. The chapter describes certain aspects of the South African mining industry which are important for exploration and which distinguish South Africa from other mineral-producing countries. Annual exploration expenditures for South Africa are shown in millions of current and constant (1982) and in figure 5-2 for the period from 1960 to 1983. The data include exploration for nonfuel minerals as well as two mineral fuels - uranium and coal

  8. CCDTL conditioning report: Module 2 and Module 3

    CERN Document Server

    Muranaka, T; Giguet, J M; Marques Balula, J; Delrieux, M

    2014-01-01

    Two CCDTL modules for Linac4 have been conditioned at SM18. The modules were tuned for resonance at 352.2 MHz, and stable operation has been achieved with 800 μs RF pulses with a repetition rate of 2 Hz. Maximum power of 700 kW loaded in cells has been achieved with a nominal Linac4 klystron and modulator setup. Since those were the first CCDTL modules to be conditioned, both hardware and software have been developed along with the conditionings.

  9. Influence of module requirements on flat plate module design evolution

    Science.gov (United States)

    Arnett, J. C.; Ross, R. G., Jr.

    1980-01-01

    Photovoltaic module design features and performance characteristics have undergone significant evolutionary changes between pre-1975 First Generation configurations and current Third Generation design technology. A major contributor to this evolution was an iterative process of continuing design guideline and specification development for major module procurements. Module manufacturers have actively responded to these evolving requirements through progressively improving designs. This iterative/feedback process is described. Interim design guidelines and preliminary design options reflecting the LSA 1982 Module Technical Readiness Specification (November 1979) are described with respect to previous design and performance requirements.

  10. Bill would expand ocean exploration

    Science.gov (United States)

    Showstack, Randy

    Legislation introduced by U.S. Congressman James Greenwood (R-Penn.) on June 9 could lead to increased study and exploration of the world's oceans.“The Exploration of the Seas Act” (House Resolution 2090) would direct the Secretary of Commerce to contract with the National Academy of Sciences to establish a Coordinated Oceanographic Program Advisory Panel to report to Congress on the adoption and establishment of an international effort to explore the potential of the oceans.

  11. Exploring Conditional Rewriting Logic Computations

    OpenAIRE

    Alpuente Frasnedo, María; Ballis, Demis; Frechina Navarro, Francisco; Sapina, Julia

    2015-01-01

    Trace exploration is concerned with techniques that allow computation traces to be dynamically searched for specific contents. Depending on whether the exploration is carried backward or forward, trace exploration techniques allow provenance tracking or impact tracking to be done. The aim of provenance tracking is to show how (parts of) a program output depends on (parts of) its input and to help estimate which input data need to be modified to accomplish a change in the ...

  12. Steam generator module

    International Nuclear Information System (INIS)

    The module of the steam generator is arranged such that the first working medium flows through the tubes of the heat exchange bundle and the second working medium flows through the intertube space. At least one side of the module is provided with a lid which is provided with a system of through-flow apertures. The apertures are expanded and provided with a thread in the direction of the outer side of the lid. They are coaxial with the tubes of the heat exchange bundle at the point of their anchorage in the tube plate. The apertures are closed with plugs with a male thread and the sealing surfaces are formed between the thread joint and the space of the first working medium. The plugs extend into the space of the heat exchange bundle and form a throttle which replaces the classical stop and allow for dismantling. This arrangement of the modular steam generator allows the control of the inner surfaces of heat exchange pipes and also the cleaning of these inner surfaces. (E.S.)

  13. Sustaining Exploration in Mature Basins

    International Nuclear Information System (INIS)

    Exploration is a business like any other business driven by opportunity, resources and expectation of profit. Therefore, exploration will thrive anywhere the opportunities are significant, the resources are available and the outlook for profit (or value creation) is good. To sustain exploration activities anywhere, irrespective of the environment, there must be good understanding of the drivers of these key investment criteria. This paper will examine these investment criteria as they relate to exploration business and address the peculiarity of exploration in mature basin. Mature basins are unique environment that lends themselves a mix of fears, paradigms and realities, particularly with respect to the perception of value. To sustain exploration activities in a mature basin, we need to understand these perceptions relative to the true drivers of profitability. Exploration in the mature basins can be as profitable as exploration in emerging basins if the dynamics of value definition-strategic and fiscal values are understood by operators, regulators and co ventures alike. Some suggestions are made in this presentation on what needs to be done in addressing these dynamic investment parameters and sustaining exploration activities in mature basins

  14. Avionics Architecture for Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Avionics Architectures for Exploration Project team will develop a system level environment and architecture that will accommodate equipment from multiple...

  15. RNA-seq analyses of blood-induced changes in gene expression in the mosquito vector species, Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Olson Ken E

    2011-01-01

    Full Text Available Abstract Background Hematophagy is a common trait of insect vectors of disease. Extensive genome-wide transcriptional changes occur in mosquitoes after blood meals, and these are related to digestive and reproductive processes, among others. Studies of these changes are expected to reveal molecular targets for novel vector control and pathogen transmission-blocking strategies. The mosquito Aedes aegypti (Diptera, Culicidae, a vector of Dengue viruses, Yellow Fever Virus (YFV and Chikungunya virus (CV, is the subject of this study to look at genome-wide changes in gene expression following a blood meal. Results Transcriptional changes that follow a blood meal in Ae. aegypti females were explored using RNA-seq technology. Over 30% of more than 18,000 investigated transcripts accumulate differentially in mosquitoes at five hours after a blood meal when compared to those fed only on sugar. Forty transcripts accumulate only in blood-fed mosquitoes. The list of regulated transcripts correlates with an enhancement of digestive activity and a suppression of environmental stimuli perception and innate immunity. The alignment of more than 65 million high-quality short reads to the Ae. aegypti reference genome permitted the refinement of the current annotation of transcript boundaries, as well as the discovery of novel transcripts, exons and splicing variants. Cis-regulatory elements (CRE and cis-regulatory modules (CRM enriched significantly at the 5'end flanking sequences of blood meal-regulated genes were identified. Conclusions This study provides the first global view of the changes in transcript accumulation elicited by a blood meal in Ae. aegypti females. This information permitted the identification of classes of potentially co-regulated genes and a description of biochemical and physiological events that occur immediately after blood feeding. The data presented here serve as a basis for novel vector control and pathogen transmission

  16. Semiconductor-laser modulation techniques

    International Nuclear Information System (INIS)

    Three simple modulation techniques for semiconductor lasers have been described. The first technique employs a single constant current source and is suitable for low frequency modulation up to 500 Khz. The second and third techniques employ two constant current sources each with current summing of subtraction and are suitable for higher frequency modulation up to several MHz. Schematic diagrams of designed, developed and tested circuits, implementing each of the above mentioned schemes, have also been presented. (author)

  17. Lehmer problem and Drinfeld modules

    OpenAIRE

    Demangos, Luca

    2013-01-01

    We propose a lower bound estimate in Dobrowolski's style of the canonical height on a certain family of Drinfeld modules of characteristic 0, including under some hypothesis on their degree and their base field, the complex multiplication case, extending so a previous result of L. Denis on Carlitz modules. Our study is focused on the highest possible level of precision on the parameters involved with rapport to the main values which characterize the Drinfeld module (height, base field degree ...

  18. Developments in Directional Modulation Technology

    OpenAIRE

    Ding, Yuan; Fusco, Vincent F.

    2016-01-01

    Directional modulation (DM), as a promising physical-layer security technique, is able to secure wireless communications by virtue of the property of its direction-dependent signal modulation format transmission. Here modulated signal waveform signatures can only be detected by legitimate receiver(s) positioned along a-prior assigned directions. This paper reviews the development in DM technology over recent years, and provides some recommendations for future studies.

  19. Multiple Differential Networks Strategy Reveals Carboplatin and Melphalan-Induced Dynamic Module Changes in Retinoblastoma.

    Science.gov (United States)

    Chen, Cui; Ma, Feng-Wei; Du, Cui-Yun; Wang, Ping

    2016-01-01

    BACKGROUND Retinoblastoma (RB) is the most common malignant tumor of the eye in childhood. The objective of this paper was to investigate carboplatin (CAR)- and melphalan (MEL)-induced dynamic module changes in RB based on multiple (M) differential networks, and to generate systems-level insights into RB progression. MATERIAL AND METHODS To achieve this goal, we constructed M-differential co-expression networks (DCNs), assigned a weight to each edge, and identified seed genes in M DCNs by ranking genes based on their topological features. Starting with seed genes, a module search was performed to explore candidate modules in CAR and MEL condition. M-DMs were detected according to significance evaluations of M-modules, which originated from refinement of candidate modules. Further, we revealed dynamic changes in M-DM activity and connectivity on the basis of significance of Module Connectivity Dynamic Score (MCDS). RESULTS In the present study, M=2, a total of 21 seed genes were obtained. By assessing module search, refinement, and evaluation, we gained 18 2-DMs. Moreover, 3 significant 2-DMs (Module 1, Module 2, and Module 3) with dynamic changes across CAR and MEL condition were determined, and we denoted them as dynamic modules. Module 1 had 27 nodes of which 6 were seed genes and 56 edges. Module 2 was composed of 28 nodes and 54 edges. A total of 28 nodes interacted with 45 edges presented in Module 3. CONCLUSIONS We have identified 3 dynamic modules with changes induced by CAR and MEL in RB, which might give insights in revealing molecular mechanism for RB therapy. PMID:27144687

  20. Photovoltaic concentrator module improvements study

    Energy Technology Data Exchange (ETDEWEB)

    Levy, S.L.; Kerschen, K.A. (Black and Veatch, Kansas City, MO (United States)); Hutchison, G. (Solar Kinetics, Inc., Dallas, TX (United States)); Nowlan, M.J. (Spire Corp., Bedford, MA (United States))

    1991-08-01

    This report presents results of a project to design and fabricate an improved photovoltaic concentrator module. Using previous work as a baseline, this study conducted analyses and testing to select major module components and design features. The lens parquet and concentrator solar cell were selected from the highest performing, available components. A single 185X point-focus module was fabricated by the project team and tested at Sandia. Major module characteristics include a 6 by 4 compression-molded acrylic lens parquet (0.737 m{sup 2} area), twenty-four 0.2 ohms-cm, FZ, p-Si solar cells (1.56 cm{sup 2} area) soldered to ceramic substrates and copper heat spreaders, and an aluminized steel housing with corrugated bottom. This project marked the first attempt to use prismatic covers on solar cells in a high-concentration, point-focus application. Cells with 15 percent metallization were obtained, but problems with the fabrication and placement of prismatic covers on these cells lead to the decision not to use covers in the prototype module. Cell assembly fabrication, module fabrication, and module optical design activities are presented here. Test results are also presented for bare cells, cell assemblies, and module. At operating conditions of 981 watts/m{sup 2} DNI and an estimated cell temperature of 65{degrees}C, the module demonstrated an efficiency of 13.9 percent prior to stressed environmental exposure. 12 refs., 56 figs., 7 tabs.

  1. Adjustable extender for instrument module

    International Nuclear Information System (INIS)

    A blank extender module used to mount an instrument module in front of its console for repair or test purposes has been equipped with a rotatable mount and means for locking the mount at various angles of rotation for easy accessibility. The rotatable mount includes a horizontal conduit supported by bearings within the blank module. The conduit is spring-biased in a retracted position within the blank module and in this position a small gear mounted on the conduit periphery is locked by a fixed pawl. The conduit and instrument mount can be pulled into an extended position with the gear clearing the pawl to permit rotation and adjustment of the instrument

  2. Hybrid grapheme plasmonic waveguide modulators

    Science.gov (United States)

    Ansell, D.; Thackray, B. D.; Aznakayeva, D. E.; Thomas, P.; Auton, G. H.; Marshall, O. P.; Rodriguez, F. J.; Radko, I. P.; Han, Z.; Bozhevolnyi, S. I.; Grigorenko, A. N.

    2016-03-01

    The unique optical and electronic properties of graphene allow one to realize active optical devices. While several types of graphene-based photonic modulators have already been demonstrated, the potential of combining the versatility of graphene with sub-wavelength field confinement of plasmonic/metallic structures is not fully realized. Here we report fabrication and study of hybrid graphene-plasmonic modulators. We consider several types of modulators and identify the most promising one for light modulation at telecom and near-infrared. Our proof-of-concept results pave the way towards on-chip realization of efficient graphene-based active plasmonic waveguide devices for optical communications.

  3. Water-module interaction studies

    Science.gov (United States)

    Mon, G.; Wen, L.; Ross, R., Jr.

    Mechanisms by which moisture enters photovoltaic modules and techniques for reducing such interactions are reported. Results from a study of the effectiveness of various module sealants are given. Techniques for measuring the rate and quantity of moisture ingress are discussed. It is shown that scribe lines and porous frit bridging conductors provide preferential paths for moisture ingress and that moisture diffusion by surface/interfacial paths is considerably more rapid than diffusion by bulk paths, which implies that thin-film substrate and supersubstrate modules are much more vulnerable to moist environments than are bulk-encapsulated crystalline-silicon modules. Design approaches that reduce moisture entry are discussed.

  4. Learning, Exploration and Chaotic Policies

    Science.gov (United States)

    Potapov, Alexei B.; Ali, M. K.

    We consider different versions of exploration in reinforcement learning. For the test problem, we use navigation in a shortcut maze. It is shown that chaotic ɛ-greedy policy may be as efficient as a random one. The best results were obtained with a model chaotic neuron. Therefore, exploration strategy can be implemented in a deterministic learning system such as a neural network.

  5. Exploring Civilizations with 'Seven Wolves'

    Institute of Scientific and Technical Information of China (English)

    Yang Jie

    2007-01-01

    @@ Beijing - A farewell party for the CCTV (China Central Television) crew 'Road to Civilizations-Global Exploration Tour of World Major Civilizations' - the world's first TV series documenting the journey of exploring the 12 civilizations in the human world, was sponsored by Fujian Septwolves Industry Co., Ltd and held at the Beijing Landmark hotel on 16 January.

  6. Colombia extends its exploration horizon

    International Nuclear Information System (INIS)

    The Return 1 Contract, currently being awarded under the tender system, faithfully reflects Colombia's new approach to hydrocarbon exploration and exploitation. This policy aims to increase reserves and has Ecopetrol assume a more aggressive role in its direct activities by sharing the exploration risks with private partners

  7. Modulated differential scanning calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Sauerbrunn, S.R.; Crowe, B.S.; Reading, M. [TA Instruments Inc., New Castle, DE (United States)

    1993-12-31

    Modulated DSC (MDSC){sup tm} is a new patent-pending extension to conventional DSC which provides information about the reversing and nonreversing characteristics of thermal events. This additional information aids interpretation and allows unique insights into the structure and behavior of materials. Data presented will demonstrate three uses of MDSC. First, the overlapping crystallization peak and glass transition in a bilayer film of polycarbonate and PET are separated by MDSC. Second, the glass transition and endothermic relaxation of epoxy are separated. Third, MDSC gives a direct measurement of the sample heat capacity. The ability to separate reversing and nonreversing transitions, as well as the ability to directly measure heat capacity, offers thermal analysis another tool for solving tough materials characterization problems.

  8. Modulated structure of nepheline

    OpenAIRE

    Friese, K.; Grzechnik, A.; Petricek, V.; Schönleber, A.; Smaalen, S. van; Morgenroth, W.

    2011-01-01

    The incommensurately modulated structure of a natural nepheline of composition K(0.54)Na(3.24)Ca(0.03)Al(3.84)Si(4.16)O(16) has been determined in superspace. The compound crystallizes in the trigonal centered superspace group X3(00γ)0 with γ = 0.2048 (10), X = (0, 0, 0, 0), (1/3, 2/3, 0, 2/3), (2/3, 1/3, 0, 1/3), a = 17.2889 (8) and c = 8.3622 (10) Å. The structure is characterized by a framework of corner-connected (Al,Si)O(4) tetrahedra. The additional cations are incorporated in two diffe...

  9. Digital Communication and Modulation

    DEFF Research Database (Denmark)

    Sørensen, John Aasted

    2011-01-01

    communication system.   Sessions in class with active participation by the students. The time will be divided between lectures and the students solving problems, including simulating digital communication building blocks in Matlab. Combines lectures and hands-on work. Semester: E2011 Extent: 7.5 ects......, the fundamental principles for modulation and detection in Gaussian noise is treated. This includes the principles for the determination of the bit-error rate for a digital communication system. During the course, a selection of small Matlab exercises are prepared, for simulation of parts of a....... Performance of a Digital Comunication System. Prepare and explain a model for bit-error probability versus the energy used per bit and channel noise, corresponding to the specific course contents. System Simulation. Prepare and explain a simulation program in Matlab for simulating a minor part of a digital...

  10. Digital Communication and Modulation

    DEFF Research Database (Denmark)

    Sørensen, John Aasted

    2011-01-01

    communication system. Sessions in class with active participation by the students. The time will be divided between lectures and the students solving problems, including simulating digital communication building blocks in Matlab. Combines lectures and hands-on work. Semester: F2011 Extent: 7.5 ects......, the fundamental principles for modulation and detection in Gaussian noise is treated. This includes the principles for the determination of the bit-error rate for a digital communication system. During the course, a selection of small Matlab exercises are prepared, for simulation of parts of a....... Performance of a Digital Comunication System. Prepare and explain a model for bit-error probability versus the energy used per bit and channel noise, corresponding to the specific course contents. System Simulation. Prepare and explain a simulation program in Matlab for simulating a minor part of a digital...

  11. Whistler modulational instability.

    Science.gov (United States)

    Brinca, A. L.

    1973-01-01

    Derivation of the modulational instability characteristics of whistlers in cold and hot plasmas. The cold-plasma analysis considers both ion motion and relativistic effects; the unstable band, with a growth rate proportional to (B/B sub zero)squared, is contiguous to Omega sub e/4 and, depending on the plasma density, lies above or below that frequency (Omega sub e is the electron cyclotron frequency of the static magnetic field; B and B sub zero are the whistler and static magnetic fields). In hot plasmas, stability occurs between Omega sub e/4 and Omega prime (less than Omega sub e), with Omega prime depending mainly on the mean energy and anisotropy of the energetic electron population; the complementary unstable band has a growth rate proportional to (B/B sub zero) to the 1/2 power. The relevance of the instability to whistlers in the magnetosphere is discussed.

  12. New pulse modulator with low switching frequency

    OpenAIRE

    Golub V. S.

    2014-01-01

    The author presents an integrating pulse modulator (analog signal converter) with the pulse frequency and duration modulation similar to sigma-delta modulation (with low switching frequency), without quantization. The modulator is characterized by the absence of the quantization noise inherent in sigma-delta modulator, and a low switching frequency, unlike the pulse-frequency modulator. The modulator is recommended, in particular, to convert signals at the input of the class D power amplifier.

  13. International Collaboration for Venus Exploration

    Science.gov (United States)

    Cutts, James; Limaye, Sanjay; Zasova, Ludmila; Wilson, Colin; Ocampo, Adriana; Glaze, Lori; Svedhem, H.; Nakamura, Masato; Widemann, Thomas

    The Venus Exploration Analysis Group (VEXAG) was established by NASA in July 2005 to identify scientific priorities and strategy for exploration of Venus. From the outset, VEXAG has been open to the international community participation and has followed the progress of the ESA Venus Express Mission and the JAXA Akasuki mission as well exploring potential broad international partnerships for Venus exploration through coordinated science and missions. This paper discussed three mechanisms through which these collaborations are being explored in which VEXAG members participate One pathway for international collaboration has been through COSPAR. The International Venus Exploration Working Group (IVEWG) was formed during the 2012 COSPAR general assembly in Mysore, India. Another potentially significant outcome has been the IVEWG’s efforts to foster a formal dialog between IKI and NASA/PSD on the proposed Venera D mission resulting in a meeting in June 2013 to be followed by a discussion at the 4MS3 conference in October 2013. This has now resulted in an agreement between NASA/PSD and IKI to form a joint Science Definition Team for Venera D. A second pathway has been through an international focus on comparative climatology. Scientists from the established space faring nations participated in a first international conference on Comparative Climatology for Terrestrial Planet (CCTP) in Boulder Colorado in June 2012 sponsored by several international scientific organizations. A second conference is planned for 2015. The Planetary Robotics Exploration Coordinating Group (PRECG) of International Academy of Astronautics (IAA) the IAA has been focusing on exploring affordable contributions to the robotic exploration by non-space-faring nations wishing to get involved in planetary exploration. PRECG has sponsored a two year study of Comparative Climatology for which Venus is the focal point and focused on engaging nations without deep space exploration capabilities. A third

  14. Parametric and modulational instabilities of the discrete nonlinear Schroedinger equation

    International Nuclear Information System (INIS)

    We examine the parametric and modulational instabilities arising in a non-autonomous, discrete nonlinear Schroedinger equation. The principal motivation for our study stems from the dynamics of Bose-Einstein condensates trapped in a deep optical lattice. We find that under periodic variations of the heights of the interwell barriers (or equivalently of the scattering length), in addition to the modulational instability, a window of parametric instability becomes available to the system. We explore this instability through multiple-scale analysis and identify it numerically. Its principal dynamical characteristic is that, typically, it develops over much larger times than the modulational instability, a feature that is qualitatively justified by comparison of the corresponding instability growth rates

  15. Aligned natural inflation with modulations

    Science.gov (United States)

    Choi, Kiwoon; Kim, Hyungjin

    2016-08-01

    The weak gravity conjecture applied for the aligned natural inflation indicates that generically there can be a modulation of the inflaton potential, with a period determined by sub-Planckian axion scale. We study the oscillations in the primordial power spectrum induced by such modulation, and discuss the resulting observational constraints on the model.

  16. Aligned natural inflation with modulations

    CERN Document Server

    Choi, Kiwoon

    2015-01-01

    The weak gravity conjecture applied for the aligned natural inflation indicates that generically there can be a modulation of the inflaton potential, with a period determined by sub-Planckian axion scale. We study the oscillations in the primordial power spectrum induced by such modulation, and discuss the resulting observational constraints on the model.

  17. Aligned natural inflation with modulations

    Directory of Open Access Journals (Sweden)

    Kiwoon Choi

    2016-08-01

    Full Text Available The weak gravity conjecture applied for the aligned natural inflation indicates that generically there can be a modulation of the inflaton potential, with a period determined by sub-Planckian axion scale. We study the oscillations in the primordial power spectrum induced by such modulation, and discuss the resulting observational constraints on the model.

  18. Aligned natural inflation with modulations

    OpenAIRE

    Kiwoon Choi; Hyungjin Kim

    2016-01-01

    The weak gravity conjecture applied for the aligned natural inflation indicates that generically there can be a modulation of the inflaton potential, with a period determined by sub-Planckian axion scale. We study the oscillations in the primordial power spectrum induced by such modulation, and discuss the resulting observational constraints on the model.

  19. Modular crystals as modulated structures

    DEFF Research Database (Denmark)

    Elcoro, L.; Perez-Mato, J.M.; Friese, K.; Petricek, V.; Balic Zunic, Tonci; Olsen, L.A.

    2008-01-01

    The use of the superspace formalism is extended to the description and refinement of the homologous series of modular structures with two symmetry-related modules with different orientations. The lillianite homologous series has been taken as a study case. Starting from a commensurate modulated...

  20. Input/output interface module

    Science.gov (United States)

    Ozyazici, E. M.

    1980-01-01

    Module detects level changes in any of its 16 inputs, transfers changes to its outputs, and generates interrupts when changes are detected. Up to four changes-in-state per line are stored for later retrieval by controlling computer. Using standard TTL logic, module fits 19-inch rack-mounted console.

  1. Voice recording module in PACS

    International Nuclear Information System (INIS)

    This paper discusses the development and implementation of picture archiving and communications system (PACS) modules and their value in reducing the burden of storage, transmission, and access to patient image files. The authors describe the integration of a voice-recording module in the existing PACS system. The implementation procedure is presented and the benefits are given

  2. Exploring Venus: the Venus Exploration Analysis Group (VEXAG)

    Science.gov (United States)

    Ocampo, A.; Atreya, S.; Thompson, T.; Luhmann, J.; Mackwell, S.; Baines, K.; Cutts, J.; Robinson, J.; Saunders, S.

    In July 2005 NASA s Planetary Division established the Venus Exploration Analysis Group VEXAG http www lpi usra edu vexag in order to engage the scientific community at large in identifying scientific priorities and strategies for the exploration of Venus VEXAG is a community-based forum open to all interested in the exploration of Venus VEXAG was designed to provide scientific input and technology development plans for planning and prioritizing the study of Venus over the next several decades including a Venus surface sample return VEXAG regularly evaluates NASA s Venus exploration goals scientific objectives investigations and critical measurement requirements including the recommendations in the National Research Council Decadal Survey and NASA s Solar System Exploration Strategic Roadmap VEXAG will take into consideration the latest scientific results from ESA s Venus Express mission and the MESSENGER flybys as well as the results anticipated from JAXA s Venus Climate Orbiter together with science community inputs from venues such as the February 13-16 2006 AGU Chapman Conference to identify the scientific priorities and strategies for future NASA Venus exploration VEXAG is composed of two co-chairs Sushil Atreya University of Michigan Ann Arbor and Janet Luhmann University of California Berkeley VEXAG has formed three focus groups in the areas of 1 Planetary Formation and Evolution Surface and Interior Volcanism Geodynamics etc Focus Group Lead Steve Mackwell LPI 2 Atmospheric Evolution Dynamics Meteorology

  3. Modulational instability of two waves

    International Nuclear Information System (INIS)

    The stability of a plasma in the presence of two propagating waves (modulation interaction) is considered. It is shown under what circumstances it is necessary to use open-quotes renormalizedclose quotes expressions for both the linear dielectric function and the effective third-order response. The typical behavior of both kinds of interaction are found for the specific case of Langmuir waves in a uniform and isotropic collisionless plasma. Criteria are established under which it is possible to disregard the effect of the interference terms in both the zeroth approximation and in the equations for the modulational perturbations when studying the modulational interaction of two pump waves. The calculated modulational instability growth rates are compared with the growth rates of the modulational instability for a single monochromatic mode. 13 refs

  4. Modulated amplitude waves in Bose-Einstein condensates

    International Nuclear Information System (INIS)

    We analyze spatiotemporal structures in the Gross-Pitaevskii equation to study the dynamics of quasi-one-dimensional Bose-Einstein condensates (BECs) with mean-field interactions. A coherent structure ansatz yields a parametrically forced nonlinear oscillator, to which we apply Lindstedt's method and multiple-scale perturbation theory to determine the dependence of the intensity of periodic orbits ('modulated amplitude waves') on their wave number. We explore BEC band structure in detail using Hamiltonian perturbation theory and supporting numerical simulations

  5. Hsp90 modulates CAG repeat instability in human cells

    OpenAIRE

    Mittelman, David; Sykoudis, Kristen; Hersh, Megan; Lin, Yunfu; Wilson, John H.

    2010-01-01

    The Hsp90 molecular chaperone has been implicated as a contributor to evolution in several organisms by revealing cryptic variation that can yield dramatic phenotypes when the chaperone is diverted from its normal functions by environmental stress. In addition, as a cancer drug target, Hsp90 inhibition has been documented to sensitize cells to DNA-damaging agents, suggesting a function for Hsp90 in DNA repair. Here we explore the potential role of Hsp90 in modulating the stability of nucleoti...

  6. Module for adaptative teaching planning for a tutoring system

    OpenAIRE

    Ceyca Ceyca, Jorge Omar; Pazos Rangel, Rodolfo A.; Ruiz Vanoye, Jorge Alberto

    2007-01-01

    The teaching process has been strengthened by the emergence of modern computer technologies, which have permitted developing distance education mainly through the use of the Internet. In this field tutoring systems have become one the most benefited and important tools for teaching. However, adapting tutoring systems to students’ capacity is one the issues that has just begun being explored [1, 2]. This paper describes a module for adaptive teaching planning for a tutoring system that is u...

  7. Development of food ingredients for modulation of glycemia

    OpenAIRE

    Kett, Anthony Paul

    2013-01-01

    Starches are a source of digestible carbohydrate and are frequently used in formulated food products in the presence of other carbohydrates, proteins and fat. This thesis explored the effect of addition of neutral (Konjac glucomannan) or charged (milk proteins) polymers on the physical characteristics and digestion kinetics of waxy maize starch. The aim was to identify mechanisms to modulate the pasting properties and subsequent susceptibility to amylolytic digestion. Addition of αs- or β-cas...

  8. Electric field switching in a resonant tunneling diode electroabsorption modulator

    OpenAIRE

    Figueiredo, J.M.L.; Ironside, C. N.; Stanley, C.R.

    2005-01-01

    The basic mechanism underlying electric field switching produced by a resonant tunnelling diode (RTD) is analysed and the theory compared with experimental results; agreement to within 12% is achieved. The electro-absorption modulator (EAM) device potential of this effect is explored in an optical waveguide configuration. It is shown that a RTD-EAM can provide significant absorption coefficient change, via the Franz-Keldysh effect, at appropriate optical communication wavelengths around 1550 ...

  9. Endocannabinoids modulate human blood–brain barrier permeability in vitro

    OpenAIRE

    Hind, William H.; Tufarelli, Cristina; Neophytou, Maria; Anderson, Susan I; England, Timothy J.; O'Sullivan, Saoirse E

    2015-01-01

    Background and Purpose Endocannabinoids alter permeability at various epithelial barriers, and cannabinoid receptors and endocannabinoid levels are elevated by stroke, with potential neuroprotective effects. We therefore explored the role of endocannabinoids in modulating blood–brain barrier (BBB) permeability in normal conditions and in an ischaemia/reperfusion model. Experimental Approach Human brain microvascular endothelial cell and astrocyte co-cultures modelled the BBB. Ischaemia was mo...

  10. What Can "Social Practice" Theory and "Socio-Cultural" Theory Contribute to Our Understanding of the Processes of Module Design?

    Science.gov (United States)

    Binns, Carole

    2015-01-01

    This article discusses the data obtained from an online survey of academic staff who are involved in module design and who are employed within one university. The survey was used as a baselining tool to explore the nature of current module design practice within the survey sample. Do academics consistently employ the pragmatic approaches…

  11. Identifying Effective Design Features of Technology-Infused Inquiry Learning Modules: A Two-Year Study of Students' Inquiry Abilities

    Science.gov (United States)

    Hsu, Ying-Shao; Fang, Su-Chi; Zhang, Wen-Xin; Hsin-Kai, Wu; Wu, Pai-Hsing; Hwang, Fu-Kwun

    2016-01-01

    The two-year study aimed to explore how students' development of different inquiry abilities actually benefited from the design of technology-infused learning modules. Three learning modules on the topics of seasons, environmental issues and air pollution were developed to facilitate students' inquiry abilities: questioning, planning, analyzing,…

  12. Borehole logging for uranium exploration

    International Nuclear Information System (INIS)

    The present text has been prepared taking into account the requirements of both developing countries, which might be at an incipient stage of uranium exploration, and industrialized countries, where more advanced exploration and resource evaluation techniques are commonly in use. While it was felt necessary to include some discussion of exploration concepts and fundamental physical principles underlying various logging methods, it was not the intention of the consultants to provide a thorough, detailed explanation of the various techniques, or even to give a comprehensive listing thereof. However, a list of references has been included, and it is strongly recommended that the serious student of mineral logging consult this list for further guidance

  13. Exploring Geometric Shapes with Touch

    CERN Document Server

    Pietrzak, Thomas; Brewster, Stephen A; Martin, Benoît; Pecci, Isabelle; 10.1007/978-3-642-03655-2_18

    2012-01-01

    We propose a new technique to help users to explore geometric shapes without vision. This technique is based on a guidance using directional cues with a pin array. This is an alternative to the usual technique that consists of raising the pins corresponding to dark pixels around the cursor. In this paper we compare the exploration of geometric shapes with our new technique in unimanual and bimanual conditions. The users made fewer errors in unimanual condition than in bimanual condition. However they did not explore the shapes more quickly and there was no difference in confidence in their answer.

  14. Exploration through Business Model Innovation

    DEFF Research Database (Denmark)

    Knab, Sebastian; Rohrbeck, René

    2015-01-01

    utilities in the emerging virtual power plant market. Based on the behavioral theory of the firm, we study how the cognitive and physical elements of an incumbent’s strategy can be changed and how these changes affect its business model innovation activities in the exploration process. Our preliminary......With this research we aim to enhance our understanding about how incumbents can explore emerging opportunities through business model innovation. Using a multiple-case, longitudinal research design spanning 2008 to 2014 we investigate exploration activities of the four largest German energy...

  15. Force Modulator System

    Energy Technology Data Exchange (ETDEWEB)

    Redmond Clark

    2009-04-30

    Many metal parts manufacturers use large metal presses to shape sheet metal into finished products like car body parts, jet wing and fuselage surfaces, etc. These metal presses take sheet metal and - with enormous force - reshape the metal into a fully formed part in a manner of seconds. Although highly efficient, the forces involved in forming metal parts also damage the press itself, limit the metals used in part production, slow press operations and, when not properly controlled, cause the manufacture of large volumes of defective metal parts. To date, the metal-forming industry has not been able to develop a metal-holding technology that allows full control of press forces during the part forming process. This is of particular importance in the automotive lightweighting efforts under way in the US automotive manufacturing marketplace. Metalforming Controls Technology Inc. (MC2) has developed a patented press control system called the Force Modulator that has the ability to control these press forces, allowing a breakthrough in stamping process control. The technology includes a series of hydraulic cylinders that provide controlled tonnage at all points in the forming process. At the same time, the unique cylinder design allows for the generation of very high levels of clamping forces (very high tonnages) in very small spaces; a requirement for forming medium and large panels out of HSS and AHSS. Successful production application of these systems testing at multiple stamping operations - including Ford and Chrysler - has validated the capabilities and economic benefits of the system. Although this technology has been adopted in a number of stamping operations, one of the primary barriers to faster adoption and application of this technology in HSS projects is system cost. The cost issue has surfaced because the systems currently in use are built for each individual die as a custom application, thus driving higher tooling costs. This project proposed to better

  16. New NASA Technologies for Space Exploration

    Science.gov (United States)

    Calle, Carlos I.

    2015-01-01

    NASA is developing new technologies to enable planetary exploration. NASA's Space Launch System is an advance vehicle for exploration beyond LEO. Robotic explorers like the Mars Science Laboratory are exploring Mars, making discoveries that will make possible the future human exploration of the planet. In this presentation, we report on technologies being developed at NASA KSC for planetary exploration.

  17. ABSOLUTELY E-PURE MODULES AND E-PURE SPLIT MODULES

    Institute of Scientific and Technical Information of China (English)

    Yan Hangyu

    2011-01-01

    We first introduce the concepts of absolutely E-pure modules and Epure split modules. Then, we characterize the IF rings in terms of absolutely E-pure modules. The E-pure split modules are also characterized.

  18. Programmable Thermostat Module Upgrade for the Multipurpose Logistics Module

    Science.gov (United States)

    Clark, D. W.; Glasgow, S. d.; Reagan, S. E.; Presson, K. H.; Howard, D. E.; Smith, D. A.

    2007-01-01

    The STS-121/ULF 1.1 mission was the maiden flight of the programmable thermostat module (PTM) system used to control the 28 V shell heaters on the multi-purpose logistics module (MPLM). These PTMs, in conjunction with a data recorder module (DRM), provide continuous closed loop temperature control and data recording of MPLM on-orbit heater operations. This Technical Memorandum discusses the hardware design, development, test, and verification (DDT&V) activities performed at the Marshall Space Flight Center as well as the operational implementation and mission performance.

  19. Opinion dynamics with disagreement and modulated information

    CERN Document Server

    Sîrbu, Alina; Servedio, Vito D P; Tria, Francesca

    2012-01-01

    Opinion dynamics concerns social processes through which populations or groups of individuals agree or disagree on specific issues. As such, modelling opinion dynamics represents an important research area that has been progressively acquiring relevance in many different domains. Existing approaches have mostly represented opinions through discrete binary or continuous variables by exploring a whole panoply of cases: e.g. independence, noise, external effects, multiple issues. In most of these cases the crucial ingredient is an attractive dynamics through which similar or similar enough agents get closer. Only rarely the possibility of explicit disagreement has been taken into account (i.e., the possibility for a repulsive interaction among individuals' opinions), and mostly for discrete or 1-dimensional opinions, through the introduction of additional model parameters. Here we introduce a new model of opinion formation, which focuses on the interplay between the possibility of explicit disagreement, modulate...

  20. Ferrite Nanoparticles in Pharmacological Modulation of Angiogenesis

    Science.gov (United States)

    Deshmukh, Aparna; Radha, S.; Khan, Y.; Tilak, Priya

    2011-07-01

    Nanoparticles are being explored in the targeted drug delivery of pharmacological agents : angiogenesis being one such novel application which involves formation of new blood vessels or branching of existing ones. The present study involves the use of ferrite nanoparticles for precise therapeutic modulation of angiogenesis. The ferrite nanoparticles synthesized by co-precipitation of ferrous and ferric salts by a suitable base, were found to be 10-20 nm from X-ray diffraction and TEM measurements. The magnetization measurements showed superparamagnetic behavior of the uncoated nanoparticles. These ferrite nanoparticles were found to be bio-compatible with lymphocytes and neural cell lines from the biochemical assays. The chick chorioallantoic membrane(CAM) from the shell of fertile white Leghorn eggs was chosen as a model to study angiogenic activity. An enhancement in the angiogenic activity in the CAM due to addition of uncoated ferrite nanoparticles was observed.

  1. cis Determinants of Promoter Threshold and Activation Timescale

    Directory of Open Access Journals (Sweden)

    Anders S. Hansen

    2015-08-01

    Full Text Available Although the relationship between DNA cis-regulatory sequences and gene expression has been extensively studied at steady state, how cis-regulatory sequences affect the dynamics of gene induction is not known. The dynamics of gene induction can be described by the promoter activation timescale (AcTime and amplitude threshold (AmpThr. Combining high-throughput microfluidics with quantitative time-lapse microscopy, we control the activation dynamics of the budding yeast transcription factor, Msn2, and reveal how cis-regulatory motifs in 20 promoter variants of the Msn2-target-gene SIP18 affect AcTime and AmpThr. By modulating Msn2 binding sites, we can decouple AmpThr from AcTime and switch the SIP18 promoter class from high AmpThr and slow AcTime to low AmpThr and either fast or slow AcTime. We present a model that quantitatively explains gene-induction dynamics on the basis of the Msn2-binding-site number, TATA box location, and promoter nucleosome organization. Overall, we elucidate the cis-regulatory logic underlying promoter decoding of TF dynamics.

  2. Exploration in the United States

    International Nuclear Information System (INIS)

    This chapter examines issues on U.S. exploration expenditures and discoveries available in 1984 when the chapter was completed. Reviewing the limitations of these data as part of the analysis the section presents two measures of exploration success: gross value of discoveries from 1940 to 1982 and success ratios from 1955 to 1982. It also analyzes the distribution of success among various types of companies and geologic deposit types. For uranium, exploration from 1940 to 1957 supplied adequate reserves for nuclear weapons. Development of nuclear power plants led to another boom between 1967 and 1980, largely terminated by major high-grade discoveries in Canada and Australia, along with decreased demand. Uranium exploration is now dormant

  3. Electromagnetic exploration system. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    1978-11-01

    A design for a cost effective, highly flexible, and portable controlled source EM exploration system is presented. The design goals of the CMOS micro-processor based receiver and its companion transmitter are listed. (MHR)

  4. Mars Exploration Rover Surface Operations

    Science.gov (United States)

    Erickson, J. K.; Adler, M.; Crisp, J.; Mishkin, A.; Welch, R.

    2002-01-01

    The Mars Exploration Rover Project is an ambitious mission to land two highly capable rovers on Mars and concurrently explore the Martian surface for three months each. Launching in 2003, surface operations will commence on January 4, 2004 with the first landing, followed by the second landing on January 25. The prime mission for the second rover will end on April 27, 2004. The science objectives of exploring multiple locations within each of two widely separated and scientifically distinct landing sites will be accomplished along with the demonstration of key surface exploration technologies for future missions. This paper will provide an overview of the planned mission, and also focus on the different operations challenges inherent in operating these two very off road vehicles, and the solutions adopted to enable the best utilization of their capabilities for high science return and responsiveness to scientific discovery.

  5. Isotope analysis in petroleum exploration

    International Nuclear Information System (INIS)

    The study about isotopic analysis in petroleum exploration performed at Petrobras Research Center is showed. The results of the petroleum recuperation in same Brazilian basin and shelves are comented. (L.H.L.L.)

  6. Contemporary Priorities for Mars Exploration

    Science.gov (United States)

    Eisen, H.; Sherwood, B.

    2012-06-01

    Human/robotic exploration implemented by an SMD/HEOMD/OCT partnership should refocus mission objectives beyond either refining prior measurements, or fixating on a singular sample return Pathway. The opportunity cost of default is too high.

  7. Exobiology in Solar System Exploration

    Science.gov (United States)

    Carle, Glenn C. (Editor); Schwartz, Deborah E. (Editor); Huntington, Judith L. (Editor)

    1992-01-01

    A symposium, 'Exobiology in Solar System Exploration,' was held on 24-26 Aug. 1988. The symposium provided an in-depth investigation of the role of Exobiology in solar system exploration. It is expected that the symposium will provide direction for future participation of the Exobiology community in solar system exploration and alert the Planetary community to the continued importance of an Exobiology Flight Program. Although the focus of the symposium was primarily on Exobiology in solar system exploration missions, several ground based and Earth-orbital projects such as the Search for Extraterrestrial Intelligence, Gas Grain Facility, and Cosmic Dust Collection Facility represent upcoming research opportunities planned to accommodate the goals and objectives of the Exobiology community as well. This report contains papers for all but one of the presentations given at the symposium.

  8. The business of petroleum exploration

    International Nuclear Information System (INIS)

    This book contains the proceedings of the Business of Petroleum Exploration. The following topics are included: Petroleum business; Economic aspects of the business; Managing business; and Legal, Political, Ethical and environment aspects of the business

  9. OCGen Module Mooring Project

    Energy Technology Data Exchange (ETDEWEB)

    McEntee, Jarlath [Ocean Renewable Power Company, LLC, Portland, ME (United States)

    2015-02-06

    Ocean Renewable Power Company's OCGen Module Mooring Project provided an extensive research, design, development, testing and data collection effort and analysis conducted with respect to a positively buoyant, submerged MHK device secured to the seabed using a tensioned mooring system. Different analytic tools were evaluated for their utility in the design of submerged systems and their moorings. Deployment and testing of a prototype OCGen® system provided significant data related to mooring line loads and system attitude and station keeping. Mooring line loads were measured in situ and reported against flow speeds. The Project made a significant step in the development of designs, methodologies and practices related to floating and mooring of marine hydrokinetic (MHK) devices. Importantly for Ocean Renewable Power Company, the Project provided a sound basis for advancing a technically and commercially viable OCGen® Power System. The OCGen® Power System is unique in the MHK industry and, in itself, offers distinct advantages of MHK devices that are secured to the seabed using fixed structural frames. Foremost among these advantages are capital and operating cost reductions and increased power extraction by allowing the device to be placed at the most energetic level of the water column.

  10. Living Systems Energy Module

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-26

    The Living Systems Energy Module, renamed Voyage from the Sun, is a twenty-lesson curriculum designed to introduce students to the major ways in which energy is important in living systems. Voyage from the Sun tells the story of energy, describing its solar origins, how it is incorporated into living terrestrial systems through photosynthesis, how it flows from plants to herbivorous animals, and from herbivores to carnivores. A significant part of the unit is devoted to examining how humans use energy, and how human impact on natural habitats affects ecosystems. As students proceed through the unit, they read chapters of Voyage from the Sun, a comic book that describes the flow of energy in story form (Appendix A). During the course of the unit, an ``Energy Pyramid`` is erected in the classroom. This three-dimensional structure serves as a classroom exhibit, reminding students daily of the importance of energy and of the fragile nature of our living planet. Interactive activities teach students about adaptations that allow plants and animals to acquire, to use and to conserve energy. A complete list of curricular materials and copies of all activity sheets appear in Appendix B.

  11. Fiber Attachment Module Experiment

    Science.gov (United States)

    Agostini, Reinaldo J.

    2014-01-01

    Hollow Fiber Membrane Bioreactors (HFMB) are ideal systems for biological pretreatment of wastewater, however, optimization is still underway. The Fiber Attachment Module Experiment (FAME) allows the simultaneous testing of potential materials, treatments on these and varying inoculums. Polydimethylsiloxane (PDMS), the material chosen for its ideal oxygen permeation properties, was treated with 1 sodium hydroxide 0.1 M ether for 18 seconds and ultraviolet (UV) irradiation oxygen plasma (OP) exposure for 1 hour. Preliminary chemistry and visual data indicate promising treatments when using OP and sodium hydroxide as treatments for PDMS fibers; however, due to the biological nature of the experiment, time is a constraint. Sodium hydroxide treatment chemistry data shows nitrification is occurring as urea and ammonia are decreasing and nitrite is increasing. A higher amount of biofilm can also be observed for this particular case. During the final two weeks of the internship x-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and acridine orange (AO) cell counts will be employed for treatment effectiveness on the first batch of treatments (ether and sodium hydroxide). These same strategies will be used for the second batch of experiments due in four weeks (2nd week of August).

  12. Bringing life to space exploration.

    Science.gov (United States)

    Noor, A K; Doyle, R J; Venneri, S L

    1999-11-01

    Characteristics of 21st century space exploration are examined. Characteristics discussed include autonomy, evolvability, robotic outposts, and an overview of future missions. Sidebar articles examine the application of lessons from biological systems to engineered systems and mission concepts taking shape at NASA. Those mission concepts include plans for Mars missions, sample return missions for Venus and a comet nucleus, Europa orbiter and lander missions, a Titan organics explorer, and a terrestrial planet finder. PMID:11542653

  13. Designerly Ways of Exploring Crowds

    OpenAIRE

    Li, J.; Vermeeren, A.P.O.S.; De Ridder, H.

    2014-01-01

    In this article, we present examples of using designerly ways to explore “crowd” phenomenon in a cross-disciplinary project named EWiDS. The phrase ‘designerly ways’ refers to visual communication methods such as drawings and videos, which are widely acknowledged as effective approaches to crossdisciplinary collaboration. This study started with designerly ways of exploring crowd experience and crowd management. Three crowd situations, public transportation, outdoor event, and indoor event, w...

  14. Exploring Geometric Shapes with Touch

    OpenAIRE

    Pietrzak, Thomas; Crossan, Andrew; Brewster, Stephen,; Martin, Benoît; Pecci, Isabelle

    2009-01-01

    We propose a new technique to help users to explore geometric shapes without vision. This technique is based on a guidance using directional cues with a pin array. This is an alternative to the usual technique that consists of raising the pins corresponding to dark pixels around the cursor. In this paper we compare the exploration of geometric shapes with our new technique in unimanual and bimanual conditions. The users made fewer errors in unimanual condition than in bimanual condition. Howe...

  15. Exploring Marketing in Micro Firms

    OpenAIRE

    WÀgar, Karolina; Björk, Peter; Ravald, Annika; West, Björn

    2007-01-01

    Purpose - The purpose of the paper is to explore the practice of marketing in micro firms. Which are the challenges micro firms encounter and how do they handle them? Methodology - The research methodology is based on the theory-in-use approach (Zaltman, Heffring & LeMasters 1982) in order to inductively explore the practice of marketing in micro firms. The empirical findings rest on ten case studies, where data has been generated through repeated interactions with each case. Find...

  16. Guided exploration in virtual environments

    Science.gov (United States)

    Beckhaus, Steffi; Eckel, Gerhard; Strothotte, Thomas

    2001-06-01

    We describe an application supporting alternating interaction and animation for the purpose of exploration in a surround- screen projection-based virtual reality system. The exploration of an environment is a highly interactive and dynamic process in which the presentation of objects of interest can give the user guidance while exploring the scene. Previous systems for automatic presentation of models or scenes need either cinematographic rules, direct human interaction, framesets or precalculation (e.g. precalculation of paths to a predefined goal). We report on the development of a system that can deal with rapidly changing user interest in objects of a scene or model as well as with dynamic models and changes of the camera position introduced interactively by the user. It is implemented as a potential-field based camera data generating system. In this paper we describe the implementation of our approach in a virtual art museum on the CyberStage, our surround-screen projection-based stereoscopic display. The paradigm of guided exploration is introduced describing the freedom of the user to explore the museum autonomously. At the same time, if requested by the user, guided exploration provides just-in-time navigational support. The user controls this support by specifying the current field of interest in high-level search criteria. We also present an informal user study evaluating this approach.

  17. Quadratic and 2-Crossed Modules of Algebras

    Institute of Scientific and Technical Information of China (English)

    Z. Arvasi; E. Ulualan

    2007-01-01

    In this work, we define the quadratic modules for commutative algebras and give relations among 2-crossed modules, crossed squares, quadratic modules and simplicial commutative algebras with Moore complex of length 2.

  18. High-Efficiency Power Module

    Science.gov (United States)

    Simons, Rainee N. (Inventor); Wintucky, Edwin G. (Inventor)

    2015-01-01

    One or more embodiments of the present invention pertain to an all solid-state microwave power module. The module includes a plurality of solid-state amplifiers configured to amplify a signal using a low power stage, a medium power stage, and a high power stage. The module also includes a power conditioner configured to activate a voltage sequencer (e.g., bias controller) when power is received from a power source. The voltage sequencer is configured to sequentially apply voltage to a gate of each amplifier and sequentially apply voltage to a drain of each amplifier.

  19. Photovoltaic module with adhesion promoter

    Science.gov (United States)

    Xavier, Grace

    2013-10-08

    Photovoltaic modules with adhesion promoters and methods for fabricating photovoltaic modules with adhesion promoters are described. A photovoltaic module includes a solar cell including a first surface and a second surface, the second surface including a plurality of interspaced back-side contacts. A first glass layer is coupled to the first surface by a first encapsulating layer. A second glass layer is coupled to the second surface by a second encapsulating layer. At least a portion of the second encapsulating layer is bonded directly to the plurality of interspaced back-side contacts by an adhesion promoter.

  20. Matching polytopes and Specht modules

    CERN Document Server

    Liu, Ricky Ini

    2009-01-01

    We prove that the dimension of the Specht module of a forest $G$ is the same as the normalized volume of the matching polytope of $G$. We also associate to $G$ a symmetric function $s_G$ (analogous to the Schur symmetric function $s_\\lambda$ for a partition $\\lambda$) and investigate its combinatorial and representation-theoretic properties in relation to the Specht module and Schur module of $G$. We then use this to define notions of standard and semistandard tableaux for forests.

  1. Induced modules over group algebras

    CERN Document Server

    Karpilovsky, Gregory

    1990-01-01

    In 1898 Frobenius discovered a construction which, in present terminology, associates with every module of a subgroup the induced module of a group. This construction proved to be of fundamental importance and is one of the basic tools in the entire theory of group representations.This monograph is designed for research mathematicians and advanced graduate students and gives a picture of the general theory of induced modules as it exists at present. Much of the material has until now been available only in research articles. The approach is not intended to be encyclopedic, rather each topic is

  2. Modulational instabilities in discrete lattices

    International Nuclear Information System (INIS)

    We study analytically and numerically modulational instabilities in discrete nonlinear chains, taking the discrete Klein-Gordon model as an example. We show that discreteness can drastically change the conditions for modulational instability; e.g., at small wave numbers a nonlinear carrier wave is unstable to all possible modulations of its amplitude if the wave amplitude exceeds a certain threshold value. Numerical simulations show the validity of the analytical approach for the initial stage of the time evolution, provided that the harmonics generated by the nonlinear terms are considered. The long-term evolution exhibits chaoticlike states

  3. Modulation of systemic immune responses through commensal gastrointestinal microbiota.

    Directory of Open Access Journals (Sweden)

    Kyle M Schachtschneider

    Full Text Available Colonization of the gastrointestinal (GI tract is initiated during birth and continually seeded from the individual's environment. Gastrointestinal microorganisms play a central role in developing and modulating host immune responses and have been the subject of investigation over the last decades. Animal studies have demonstrated the impact of GI tract microbiota on local gastrointestinal immune responses; however, the full spectrum of action of early gastrointestinal tract stimulation and subsequent modulation of systemic immune responses is poorly understood. This study explored the utility of an oral microbial inoculum as a therapeutic tool to affect porcine systemic immune responses. For this study a litter of 12 pigs was split into two groups. One group of pigs was inoculated with a non-pathogenic oral inoculum (modulated, while another group (control was not. DNA extracted from nasal swabs and fecal samples collected throughout the study was sequenced to determine the effects of the oral inoculation on GI and respiratory microbial communities. The effects of GI microbial modulation on systemic immune responses were evaluated by experimentally infecting with the pathogen Mycoplasma hyopneumoniae. Coughing levels, pathology, toll-like receptors 2 and 6, and cytokine production were measured throughout the study. Sequencing results show a successful modulation of the GI and respiratory microbiomes through oral inoculation. Delayed type hypersensitivity responses were stronger (p = 0.07, and the average coughing levels and respiratory TNF-α variance were significantly lower in the modulated group (p<0.0001 and p = 0.0153, respectively. The M. hyopneumoniae infection study showed beneficial effects of the oral inoculum on systemic immune responses including antibody production, severity of infection and cytokine levels. These results suggest that an oral microbial inoculation can be used to modulate microbial communities, as well as

  4. Modulation of lymphopoiesis

    Energy Technology Data Exchange (ETDEWEB)

    Rosse, C.

    1991-01-01

    During the current project period we have demonstrated correspondence between animal models and in vitro models of modulated lymphopoiesis. Our finding that G-CSF, a growth factor for neutrophil granulocytes, suppresses lymphopoiesis in long term bone marrow cultures (LTBMC) has important implications both for understanding the regulatory mechanisms of hemopoiesis and for clinical use of recombinant growth factors that are beginning to be widely used for the treatment of a variety of diseases. During the present project period we adopted LTBMC systems developed by others for the purposes of our specific aims. Also we developed a novel long term culture system for NK cells. The discovery of a new growth factor, O-CSF, specific for osteoclasts and the establishment of a clonal assay system that provides evidence for a new class of hemopoietic progenitor cells, the osteoclast progenitor, are important contributions. Given the important role T cells play in the immune response and in the regulation of other lymphohemopoietic cell lineages through the lymphokines they secrete, the need for an in vitro system that lends itself to the analysis of T cell maturation and to the testing of factors that may adversely affect T lymphopoiesis cannot be overemphasized. We believe that we can exploit an advantageous set of circumstances that present an excellent opportunity for initiating a focused experimental program for developing such a system. By a systematic and selective analysis of molecular interactions between heterogenous thymic stromal cells and T cell progenitors at different stages of maturation, it will be possible for our program to define the complement of critical cellular interactions on which successive stages of T lymphopoiesis depend. The experiments we propose will lay a rational foundation for the development of a long term culture system for T lymphopoiesis. 24 refs., 7 figs.

  5. Identification of melanoma biomarkers based on network modules by integrating the human signaling network with microarrays

    Directory of Open Access Journals (Sweden)

    Chunyun Huang

    2014-01-01

    Full Text Available Background: Melanoma is a leading cause of cancer death. Thus, accurate prognostic biomarkers that will assist rational treatment planning need to be identified. Methods: Microarray analysis of melanoma and normal tissue samples was performed to identify differentially expressed modules (DEMs from the signaling network and ultimately detect molecular markers to support histological examination. Network motifs were extracted from the human signaling network. Then, significant expression-correlation differential modules were identified by comparing the network module expression-correlation differential scores under normal and disease conditions using the gene expression datasets. Finally, we obtained DEMs by the Wilcoxon rank test and considered the average gene expression level in these modules as the classification features for diagnosing melanoma. Results: In total, 99 functional DEMs were identified from the signaling network and gene expression profiles. The area under the curve scores for cancer module genes, melanoma module genes, and whole network modules are 92.4%, 90.44%, and 88.45%, respectively. The classification efficiency rates for nonmodule features are 71.04% and 79.38%, which correspond to the features of cancer genes and melanoma cancer genes, respectively. Finally, we acquired six significant molecular biomarkers, namely, module 10 (CALM3, Ca 2+ , PKC, PDGFRA, phospholipase-g, PIB5PA, and phosphatidylinositol-3-kinase, module 14 (SRC, Src homology 2 domain-containing [SHC], SAM68, GIT1, transcription factor-4, CBLB, GRB2, VAV2, LCK, YES, PTCH2, downstream of tyrosine kinase [DOK], and KIT, module 16 (ELK3, p85beta, SHC, ZFYVE9, TGFBR1, TGFBR2, CITED1, SH3KBP1, HCK, DOK, and KIT, module 45 (RB, CCND3, CCNA2, CDK4, and CDK6, module 75 (PCNA, CDK4, and CCND1, and module 114 (PSD93, NMDAR, and FYN. Conclusion: We explored the gene expression profile and signaling network in a global view and identified DEMs that can be used as

  6. Active Thermal Control System Development for Exploration

    Science.gov (United States)

    Westheimer, David

    2007-01-01

    All space vehicles or habitats require thermal management to maintain a safe and operational environment for both crew and hardware. Active Thermal Control Systems (ATCS) perform the functions of acquiring heat from both crew and hardware within a vehicle, transporting that heat throughout the vehicle, and finally rejecting that energy into space. Almost all of the energy used in a space vehicle eventually turns into heat, which must be rejected in order to maintain an energy balance and temperature control of the vehicle. For crewed vehicles, Active Thermal Control Systems are pumped fluid loops that are made up of components designed to perform these functions. NASA has been actively developing technologies that will enable future missions or will provide significant improvements over the state of the art technologies. These technologies have are targeted for application on the Crew Exploration Vehicle (CEV), or Orion, and a Lunar Surface Access Module (LSAM). The technologies that have been selected and are currently under development include: fluids that enable single loop ATCS architectures, a gravity insensitive vapor compression cycle heat pump, a sublimator with reduced sensitivity to feedwater contamination, an evaporative heat sink that can operate in multiple ambient pressure environments, a compact spray evaporator, and lightweight radiators that take advantage of carbon composites and advanced optical coatings.

  7. Capabilities of a FOXSI Small Explorer

    Science.gov (United States)

    Inglis, A. R.; Christe, S.; Glesener, L.; Krucker, S.; Dennis, B. R.; Shih, A.; Wilson-Hodge, C.; Gubarev, M.; Hudson, H. S.; Kontar, E.; Buitrago Casas, J. C.; Drake, J. F.; Caspi, A.; Holman, G.; Allred, J. C.; Ryan, D.; Alaoui, M.; White, S. M.; Saint-Hilaire, P.; Klimchuk, J. A.; Hannah, I. G.; Antiochos, S. K.; Grefenstette, B.; Ramsey, B.; Jeffrey, N. L. S.; Reep, J. W.; Schwartz, R. A.; Ireland, J.

    2015-12-01

    We present the FOXSI (Focusing Optics X-ray Solar Imager) small explorer (SMEX) concept, a mission dedicated to studying particle acceleration and energy release on the Sun. FOXSI is designed as a 3-axis stabilized spacecraft in low-Earth orbit making use of state-of-the-art grazing incidence focusing optics, allowing for direct imaging of solar X-rays. The current design being studied features three telescope modules deployed in a low-inclination low-earth orbit (LEO). With a 15 meter focal length enabled by a deployable boom, FOXSI will observe the Sun in the 3-50 keV energe range. The FOXSI imaging concept has already been tested on two sounding rocket flights, in 2012 and 2014 and on the HEROES balloon payload flight in 2013. FOXSI will image the Sun with an angular resolution of 5'', a spectral resolution of 0.5 keV, and sub-second temporal resolution using CdTe detectors. In this presentation we investigate the science objectives and targets which can be accessed from this mission. Because of the defining characteristic of FOXSI is true imaging spectroscopy with high dynamic range and sensitivity, a brand-new perspective on energy release on the Sun is possible. Some of the science targets discussed here include; flare particle acceleration processes, electron beams, return currents, sources of solar energetic particles (SEPs), as well as understanding X-ray emission from active region structures and the quiescent corona.

  8. An Embedded Reconfigurable Logic Module

    Science.gov (United States)

    Tucker, Jerry H.; Klenke, Robert H.; Shams, Qamar A. (Technical Monitor)

    2002-01-01

    A Miniature Embedded Reconfigurable Computer and Logic (MERCAL) module has been developed and verified. MERCAL was designed to be a general-purpose, universal module that that can provide significant hardware and software resources to meet the requirements of many of today's complex embedded applications. This is accomplished in the MERCAL module by combining a sub credit card size PC in a DIMM form factor with a XILINX Spartan I1 FPGA. The PC has the ability to download program files to the FPGA to configure it for different hardware functions and to transfer data to and from the FPGA via the PC's ISA bus during run time. The MERCAL module combines, in a compact package, the computational power of a 133 MHz PC with up to 150,000 gate equivalents of digital logic that can be reconfigured by software. The general architecture and functionality of the MERCAL hardware and system software are described.

  9. Photovoltaic Module Qualification Plus Testing

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, S.; Wohlgemuth, J.; Kempe, M.; Bosco, N.; Hacke, P.; Jordan, D.; Miller, D. C.; Silverman, T. J.; Phillips, N.; Earnest, T.; Romero, R.

    2013-12-01

    This report summarizes a set of test methods that are in the midst of being incorporated into IEC 61215 for certification of a module design or other tests that go beyond certification to establish bankability.

  10. Flip-Flop Digital Modulator

    Science.gov (United States)

    Eno, R. F.

    1984-01-01

    Clock switched on and off in response to data signal. Flip-flop modulator generates square-wave carrier frequency that is half clock frequency and turns carrier on and off. Final demodulator output logical inverse of data input.

  11. Ultrasound-modulated bioluminescence tomography

    Science.gov (United States)

    Bal, Guillaume; Schotland, John C.

    2014-03-01

    We propose a method to reconstruct the density of a luminescent source in a highly scattering medium from ultrasound-modulated optical measurements. Our approach is based on the solution to a hybrid inverse source problem for the diffusion equation.

  12. Defining Modules, Modularity and Modularization

    DEFF Research Database (Denmark)

    Miller, Thomas Dedenroth; Pedersen, Per Erik Elgård

    The paper describes the evolution of the concept of modularity in a historical perspective. The main reasons for modularity are: create variety, utilize similarities, and reduce complexity. The paper defines the terms: Module, modularity, and modularization....

  13. Compact energy conversion module Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This STTR project delivers a compact vibration-based Energy Conversion Module (ECM) that powers sensors for purposes like structural health monitoring (SHM). NASA...

  14. Molecular mechanisms of decreased smooth muscle differentiation marker expression after vascular injury

    OpenAIRE

    Regan, Christopher P.; Adam, Paul J.; Madsen, Cort S.; Owens, Gary K.

    2000-01-01

    While it is well established that phenotypic modulation of vascular smooth muscle cells (VSMCs) contributes to the development and progression of vascular lesions, little is known regarding the molecular mechanisms of phenotypic modulation in vivo. Here we show that vascular injury reduces transcription of VSMC differentiation marker genes, and we identify cis regulatory elements that may mediate this decrease. Using a carotid wire-injury model in mice carrying transgenes for smooth muscle α-...

  15. Factors Modulating Software Design Quality

    OpenAIRE

    S., Poornima. U.; V, Suma.

    2014-01-01

    Object oriented approach is one of the popular software development approach for managing complex systems with massive set of requirements. Unlike procedural approach, this approach captures the requirements as set of data rather than services. Further, class is considered as a key unit of the solution-domain with data and services wrapped together, representing architectural design of a basic module. Thus, system complexity is directly related to the number of modules and the degree of inter...

  16. Installing Python Modules with pip

    OpenAIRE

    Fred Gibbs

    2013-01-01

    This lesson shows you how to download and install Python modules. There are many ways to install external modules, but for the purposes of this lesson, we’re going to use a program called pip. As of Python 2.7.9 and newer, pip is installed by default. This tutorial will be helpful for anyone using older versions of Python (which are still quite common).

  17. Wideband Sigma-Delta Modulators

    OpenAIRE

    Yuan, Xiaolong

    2010-01-01

    Sigma-delta modulators (SDM) have come up as an attractive candidatefor analog-to-digital conversion in single chip front ends thanks to the continuousimproving performance. The major disadvantage is the limited bandwidthdue to the need of oversampling. Therefore, extending these convertersto broadband applications requires lowering the oversampling ratio (OSR) inorder. The aim of this thesis is the investigation on the topology and structureof sigma-delta modulators suitable for wideband app...

  18. Installing Python Modules with pip

    Directory of Open Access Journals (Sweden)

    Fred Gibbs

    2013-05-01

    Full Text Available This lesson shows you how to download and install Python modules. There are many ways to install external modules, but for the purposes of this lesson, we’re going to use a program called pip. As of Python 2.7.9 and newer, pip is installed by default. This tutorial will be helpful for anyone using older versions of Python (which are still quite common.

  19. Attentional Modulation of Binocular Rivalry

    OpenAIRE

    Chris ePaffen; David eAlais

    2011-01-01

    Ever since Wheatstone initiated the scientific study of binocular rivalry, it has been debated whether the phenomenon is under attentional control. In recent years, the issue of attentional modulation of binocular rivalry has seen a revival. Here we review the classical studies as well as recent advances in the study of attentional modulation of binocular rivalry. We show that (1) voluntary control over binocular rivalry is possible, yet limited, (2) both endogenous and exogenous attention in...

  20. Flavonoid modulation of GABAA receptors

    OpenAIRE

    Jane R. Hanrahan; Chebib, Mary; Johnston, Graham A. R.

    2011-01-01

    There has been a resurgence of interest in synthetic and plant-derived flavonoids as modulators of γ-amino butyric acid-A (GABAA) receptor function influencing inhibition mediated by the major inhibitory neurotransmitter GABA in the brain. Areas of interest include (i) flavonoids that show subtype selectivity in recombinant receptor studies in vitro consistent with their behavioural effects in vivo, (ii) flumazenil-insensitive modulation of GABAA receptor function by flavonoids, (iii) the abi...