WorldWideScience

Sample records for bacteria elicit divergent

  1. Distinct gut-derived lactic acid bacteria elicit divergent dendritic cell-mediated NK cell responses

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Zeuthen, Louise Hjerrild; Christensen, Hanne;

    2007-01-01

    Lactic acid bacteria (LAB) are abundant in the gastrointestinal tract where they continuously regulate the immune system. NK cells are potently activated by dendritic cells (DCs) matured by inflammatory stimuli, and NK cells are present in the gut epithelium and in mesenteric lymph nodes...... in their ability to induce DC-dependent IFN-gamma production by NK cells. This suggests that DCs stimulated by gut LAB may expand the pool of NK cells and increase their cytotoxic potential. Specific LAB, inducing high levels of IL-12 in DCs, may promote amplification of a type-1 response via potent stimulation...... of IFN-gamma production in NK cells. Combining IFN-gamma-inducing and non-inducing LAB completely abrogates DC-mediated IFN-gamma production by NK cells, and therefore LAB modulating IFN-gamma production in NK cells may be important regulators of the immune response....

  2. Chitin elicitation of natural product production in marine bacteria

    DEFF Research Database (Denmark)

    Månsson, Maria; Wietz, Matthias; Larsen, Thomas Ostenfeld;

    on glucose-based medium. The different phenotypic responses to a natural growth substrate may reflect different niche-adaptations or ecological functions of the compounds produced and it represents a fruitful approach for elicitation of natural product production in marine bacteria.......Genome sequences reveal that our current standard laboratory conditions only support a fraction of the potential secondary metabolism in bacteria.1 Thus, we must rethink cultivation, detection, and isolation strategies for bacterial secondary metabolites in order to explore the huge, so far...... uncharacterized chemical potential of these organisms. As part of a new project on ecology-driven drug discovery at the Technical University of Denmark, we investigate the use of chitin to elicit or alter production of antibacterial compounds in marine bacteria. Within our large collection of Gram...

  3. An ancient divergence among the bacteria. [methanogenic phylogeny

    Science.gov (United States)

    Balch, W. E.; Magrum, L. J.; Fox, G. E.; Wolfe, R. S.; Woese, C. R.

    1977-01-01

    The 16S ribosomal RNZs from two species of met methanogenic bacteria, the mesophile Methanobacterium ruminantium and the thermophile Methanobacterium thermoautotrophicum, have been characterized in terms of the oligonucleotides produced by digestion with T1 ribonuclease. These two organisms are found to be sufficiently related that they can be considered members of the same genus or family. However, they bear only slight resemblance to 'typical' Procaryotic genera; such as Escherichia, Bacillus and Anacystis. The divergence of the methanogenic bacteria from other bacteria may be the most ancient phylogenetic event yet detected - antedating considerably the divergence of the blue green algal line for example, from the main bacterial line.

  4. Assessing Associative Distance among Ideas Elicited by Tests of Divergent Thinking

    Science.gov (United States)

    Acar, Selcuk; Runco, Mark A.

    2014-01-01

    Tests of divergent thinking represent the most commonly used assessment of creative potential. Typically they are scored for total ideational output (fluency), ideational originality, and, sometimes, ideational flexibility. That scoring system provides little information about the underlying process and about the associations among ideas. It also…

  5. The major sigma factor (RpoD) from Helicobacter pylori and other gram-negative bacteria shows an enhanced rate of divergence.

    OpenAIRE

    Solnick, J. V.; Hansen, L M; Syvanen, M

    1997-01-01

    Sequence analysis of the Helicobacter pylori major sigma factor (RpoD) shows that it is highly divergent, which may be related to the marked diversity of the H. pylori chromosome. Furthermore, the rate of divergence of RpoD among other gram-negative bacteria is much greater than that among gram-positive bacteria. This suggests that RpoD from gram-negative bacteria is functionally less constrained than that from gram-positive bacteria.

  6. Psychoactive bacteria Lactobacillus rhamnosus (JB-1) elicits rapid frequency facilitation in vagal afferents.

    Science.gov (United States)

    Perez-Burgos, Azucena; Wang, Bingxian; Mao, Yu-Kang; Mistry, Bhavik; McVey Neufeld, Karen-Anne; Bienenstock, John; Kunze, Wolfgang

    2013-01-15

    Mounting evidence supports the influence of the gut microbiome on the local enteric nervous system and its effects on brain chemistry and relevant behavior. Vagal afferents are involved in some of these effects. We previously showed that ingestion of the probiotic bacterium Lactobacillus rhamnosus (JB-1) caused extensive neurochemical changes in the brain and behavior that were abrogated by prior vagotomy. Because information can be transmitted to the brain via primary afferents encoded as neuronal spike trains, our goal was to record those induced by JB-1 in vagal afferents in the mesenteric nerve bundle and thus determine the nature of the signals sent to the brain. Male Swiss Webster mice jejunal segments were cannulated ex vivo, and serosal and luminal compartments were perfused separately. Bacteria were added intraluminally. We found no evidence for translocation of labeled bacteria across the epithelium during the experiment. We recorded extracellular multi- and single-unit neuronal activity with glass suction pipettes. Within minutes of application, JB-1 increased the constitutive single- and multiunit firing rate of the mesenteric nerve bundle, but Lactobacillus salivarius (a negative control) or media alone were ineffective. JB-1 significantly augmented multiunit discharge responses to an intraluminal distension pressure of 31 hPa. Prior subdiaphragmatic vagotomy abolished all of the JB-1-evoked effects. This detailed exploration of the neuronal spike firing that encodes behavioral signaling to the brain may be useful to identify effective psychoactive bacteria and thereby offer an alternative new perspective in the field of psychiatry and comorbid conditions.

  7. Gluconacetobacter diazotrophicus Elicits a Sugarcane Defense Response Against a Pathogenic Bacteria Xanthomonas albilineans

    Science.gov (United States)

    Vinagre, Fabiano; Estevez, Yandi; Bernal, Aydiloide; Perez, Juana; Cavalcanti, Janaina; Santana, Ignacio; Hemerly, Adriana S

    2006-01-01

    A new role for the plant growth-promoting nitrogen-fixing endophytic bacteria Gluconacetobacter diazotrophicus has been identified and characterized while it is involved in the sugarcane-Xanthomonas albilineans pathogenic interactions. Living G.diazotrophicus possess and/or produce elicitor molecules which activate the sugarcane defense response resulting in the plant resistance to X. albilineans, in this particular case controlling the pathogen transmission to emerging agamic shoots. A total of 47 differentially expressed transcript derived fragments (TDFs) were identified by cDNA-AFLP. Transcripts showed significant homologies to genes of the ethylene signaling pathway (26%), proteins regulates by auxins (9%), β-1,3 Glucanase proteins (6%) and ubiquitin genes (4%), all major signaling mechanisms. Results point toward a form of induction of systemic resistance in sugarcane-G. diazotrophicus interactions which protect the plant against X. albilineans attack. PMID:19516988

  8. Horizontal Gene Transfers from Bacteria to Entamoeba Complex: A Strategy for Dating Events along Species Divergence.

    Science.gov (United States)

    Romero, Miguel; Cerritos, R; Ximenez, Cecilia

    2016-01-01

    Horizontal gene transfer has proved to be relevant in eukaryotic evolution, as it has been found more often than expected and related to adaptation to certain niches. A relatively large list of laterally transferred genes has been proposed and evaluated for the parasite Entamoeba histolytica. The goals of this work were to elucidate the importance of lateral gene transfer along the evolutionary history of some members of the genus Entamoeba, through identifying donor groups and estimating the divergence time of some of these events. In order to estimate the divergence time of some of the horizontal gene transfer events, the dating of some Entamoeba species was necessary, following an indirect dating strategy based on the fossil record of plausible hosts. The divergence between E. histolytica and E. nuttallii probably occurred 5.93 million years ago (Mya); this lineage diverged from E. dispar 9.97 Mya, while the ancestor of the latter separated from E. invadens 68.18 Mya. We estimated times for 22 transferences; the most recent occurred 31.45 Mya and the oldest 253.59 Mya. Indeed, the acquisition of genes through lateral transfer may have triggered a period of adaptive radiation, thus playing a major role in the evolution of the Entamoeba genus. PMID:27239333

  9. Deep mitochondrial divergence within a Heliconius butterfly species is not explained by cryptic speciation or endosymbiotic bacteria

    Directory of Open Access Journals (Sweden)

    Muñoz Astrid G

    2011-12-01

    Full Text Available Abstract Background Cryptic population structure can be an indicator of incipient speciation or historical processes. We investigated a previously documented deep break in the mitochondrial haplotypes of Heliconius erato chestertonii to explore the possibility of cryptic speciation, and also the possible presence of endosymbiont bacteria that might drive mitochondrial population structure. Results Among a sample of 315 individuals from 16 populations of western Colombia, two principal mtDNA clades were detected with 2.15% divergence and we confirmed this structure was weakly associated with geography. The first mtDNA clade included 87% of individuals from northern populations and was the sister group of H. erato members of Andes western, while the second clade contained most individuals from southern populations (78%, which shared haplotypes with an Ecuadorian race of H. erato. In contrast, analysis using AFLP markers showed H. e. chestertonii to be a genetically homogeneous species with no association between mitochondrial divergence and AFLP structure. The lack of congruence between molecular markers suggests that cryptic speciation is not a plausible explanation for the deep mitochondrial divergence in H. e chestertonii. We also carried out the first tests for the presence of endosymbiontic bacteria in Heliconius, and identified two distinct lineages of Wolbachia within H. e. chestertonii. However, neither of the principal mitochondrial clades of H. e. chestertonii was directly associated with the patterns of infection. Conclusions We conclude that historical demographic processes are the most likely explanation for the high mitochondrial differentiation in H. e. chestertonii, perhaps due to gene flow between Cauca valley H. e. chestertonii and west Pacific slope populations of H. erato.

  10. Divergent pro-inflammatory profile of human dendritic cells in response to commensal and pathogenic bacteria associated with the airway microbiota

    DEFF Research Database (Denmark)

    Larsen, Jeppe Madura; Steen-Jensen, Daniel Bisgaard; Laursen, Janne Marie;

    2012-01-01

    of individual bacterial species are unknown. In this study, we compared the immune stimulatory capacity on human monocyte-derived dendritic cells (DCs) of selected airway commensal and pathogenic bacteria predominantly associated with lungs of asthma or COPD patients (pathogenic Haemophillus spp. and Moraxella...... spp.), healthy lungs (commensal Prevotella spp.) or both (commensal Veillonella spp. and Actinomyces spp.). All bacteria were found to induce activation of DCs as demonstrated by similar induction of CD83, CD40 and CD86 surface expression. However, asthma and COPD-associated pathogenic bacteria...... provoked a 3-5 fold higher production of IL-23, IL-12p70 and IL-10 cytokines compared to the commensal bacteria. Based on the differential cytokine production profiles, the studied airway bacteria could be segregated into three groups (Haemophilus spp. and Moraxella spp. vs. Prevotella spp. and Veillonella...

  11. Finite Divergence

    DEFF Research Database (Denmark)

    Hansen, Michael Edberg; Pandya, P. K.; Chaochen, Zhou

    1995-01-01

    of behaviour arises in many representations of hybrid systems, and also in theories of nonlinear systems. The aim is to provide a theory where pathological behaviour such as finite divergence can be analysed-if only to prove that it does not occur in systems of interest. Finite divergence is studied using......Real-time and hybrid systems have been studied so far under the assumption of finite variability. In this paper, we consider models in which systems exhibiting finite divergence can also be analysed. In such systems, the state of the system can change infinitely often in a finite time. This kind...

  12. Diverging Cohesion?

    DEFF Research Database (Denmark)

    Charron, Nicholas

    2016-01-01

    – which we define here as a combination of impartial bureaucratic practices, corruption and the rule of law – limits, and in some cases reverses the tendency towards greater divergence linked to trade. Countries with high levels of state capacity – that is, those that have greater government effectiveness......, stronger rule of law and lower corruption – experience lower levels of divergence, as they have the mechanisms to counterbalance the strong centripetal forces linked to openness. This claim is tested on countries that have experienced relatively high levels of increases in levels of economic and political...

  13. Axiomatising Divergence

    NARCIS (Netherlands)

    Lohrey, M.; D'Argenio, P.R.; Hermanns, H.; Widmayer, P.; Triguero Ruiz, F.; Morales Bueno, R.; Hennessy, M.; Eidenbenz, S.; Conejo, R.

    2002-01-01

    This paper develops sound and complete axiomatisations for the divergence sensitive spectrum of weak bisimulation equivalence. The axiomatisations can be extended to a considerable fragment of the linear time - branching time spectrum with silent moves, partially solving an open problem posed in [5

  14. Belief Elicitation in Experiments

    DEFF Research Database (Denmark)

    Blanco, Mariana; Engelmann, Dirk; Koch, Alexander;

    Belief elicitation in economics experiments usually relies on paying subjects according to the accuracy of stated beliefs in addition to payments for other decisions. Such incentives, however, allow risk-averse subjects to hedge with their stated beliefs against adverse outcomes of other decisions...... in the experiment. This raises two questions: (i) can we trust the existing belief elicitation results, (ii) can we avoid potential hedging confounds? Our results instill confidence regarding both issues. We propose an experimental design that eliminates hedging opportunities, and use this to test for the empirical...

  15. On Mean Divergence Measures

    OpenAIRE

    Taneja, Inder Jeet

    2005-01-01

    Arithmetic, geometric and harmonic means are the three classical means famous in the literature. Another mean such as square-root mean is also known. In this paper, we have constructed divergence measures based on nonnegative differences among these means, and established an interesting inequality by use of properties of Csiszar's f-divergence. Connections of new mean divergences measures with classical divergence measures such as Jeffreys-Kullback-Leibler J-divergence, Sibson-Burbea-Rao Jens...

  16. Elicitation threshold of cobalt chloride

    DEFF Research Database (Denmark)

    Fischer, Louise A; Johansen, Jeanne D; Voelund, Aage;

    2016-01-01

    BACKGROUND: Cobalt is a strong skin sensitizer (grade 5 of 5 in the guinea-pig maximization test) that is used in various industrial and consumer applications. To prevent sensitization to cobalt and elicitation of allergic cobalt dermatitis, information about the elicitation threshold level of co...... individuals, and thereby the basis for future prevention of cobalt allergy.......BACKGROUND: Cobalt is a strong skin sensitizer (grade 5 of 5 in the guinea-pig maximization test) that is used in various industrial and consumer applications. To prevent sensitization to cobalt and elicitation of allergic cobalt dermatitis, information about the elicitation threshold level...... of cobalt is important. OBJECTIVE: To identify the dermatitis elicitation threshold levels in cobalt-allergic individuals. MATERIALS AND METHODS: Published patch test dose-response studies were reviewed to determine the elicitation dose (ED) levels in dermatitis patients with a previous positive patch test...

  17. Quantum skew divergence

    Energy Technology Data Exchange (ETDEWEB)

    Audenaert, Koenraad M. R., E-mail: koenraad.audenaert@rhul.ac.uk [Department of Mathematics, Royal Holloway University of London, Egham TW20 0EX, United Kingdom and Department of Physics and Astronomy, University of Ghent, S9, Krijgslaan 281, B-9000 Ghent (Belgium)

    2014-11-15

    In this paper, we study the quantum generalisation of the skew divergence, which is a dissimilarity measure between distributions introduced by Lee in the context of natural language processing. We provide an in-depth study of the quantum skew divergence, including its relation to other state distinguishability measures. Finally, we present a number of important applications: new continuity inequalities for the quantum Jensen-Shannon divergence and the Holevo information, and a new and short proof of Bravyi's Small Incremental Mixing conjecture.

  18. Atom laser divergence

    OpenAIRE

    Le Coq, Yann; Thywissen, Joseph H.; Rangwala, Sadiq A.; Gerbier, Fabrice; Richard, Simon; Delannoy, Guillaume; Bouyer, Philippe; Aspect, Alain

    2001-01-01

    We measure the angular divergence of a quasi-continuous, rf-outcoupled, free-falling atom laser as a function of the outcoupling frequency. The data is compared to a Gaussian-beam model of laser propagation that generalizes the standard formalism of photonic lasers. Our treatment includes diffraction, magnetic lensing, and interaction between the atom laser and the condensate. We find that the dominant source of divergence is the condensate-laser interaction.

  19. Potent and Broadly Reactive HIV-2 Neutralizing Antibodies Elicited by a Vaccinia Virus Vector Prime-C2V3C3 Polypeptide Boost Immunization Strategy▿ †

    Science.gov (United States)

    Marcelino, José Maria; Borrego, Pedro; Rocha, Cheila; Barroso, Helena; Quintas, Alexandre; Novo, Carlos; Taveira, Nuno

    2010-01-01

    Human immunodeficiency virus type 2 (HIV-2) infection affects about 1 to 2 million individuals, the majority living in West Africa, Europe, and India. As for HIV-1, new strategies for the prevention of HIV-2 infection are needed. Our aim was to produce new vaccine immunogens that elicit the production of broadly reactive HIV-2 neutralizing antibodies (NAbs). Native and truncated envelope proteins from the reference HIV-2ALI isolate were expressed in vaccinia virus or in bacteria. This source isolate was used due to its unique phenotype combining CD4 independence and CCR5 usage. NAbs were not elicited in BALB/c mice by single immunization with a truncated and fully glycosylated envelope gp125 (gp125t) or a recombinant polypeptide comprising the C2, V3, and C3 envelope regions (rpC2-C3). A strong and broad NAb response was, however, elicited in mice primed with gp125t expressed in vaccinia virus and boosted with rpC2-C3. Serum from these animals potently neutralized (median 50% neutralizing titer, 3,200) six of six highly divergent primary HIV-2 isolates. Coreceptor usage and the V3 sequence of NAb-sensitive isolates were similar to that of the vaccinating immunogen (HIV-2ALI). In contrast, NAbs were not reactive on three X4 isolates that displayed major changes in V3 loop sequence and structure. Collectively, our findings demonstrate that broadly reactive HIV-2 NAbs can be elicited by using a vaccinia virus vector-prime/rpC2-C3-boost immunization strategy and suggest a potential relationship between escape to neutralization and cell tropism. PMID:20844029

  20. Decoherence and infrared divergence

    Indian Academy of Sciences (India)

    J Kupsch

    2002-08-01

    The dynamics of a particle which is linearly coupled to a boson field is investigated. The boson field induces superselection rules for the momentum of the particle, if the field is infrared divergent. Thereby the Hamiltonian of the total system remains bounded from below.

  1. Emotion Eliciting in Affective Design

    DEFF Research Database (Denmark)

    Lai, Yoke Chin

    2014-01-01

    outlines the concept of an integrated design method that is developed to aid novice designer through the conceptual design stage. Multi-modal stimulation is used in this design method to induce user’s emotion, a key element in the user’s mental model. Visio-haptic Augmented Reality technology is integrated...... with 3D digital prototype as emotion stimulus. To form a closed loop reflective model, the emotion response from the user is assessed with an emotion assessment tool. Emotion ontology is established to form the backbone of the emotion assessment tool.......A successful product needs the designer’s conceptual model congruent with the user’s mental model. The fundamental affective design principle also applies to assistive product design. Eliciting effectively the user’s mental model has been a big challenge for most novice designers. This paper...

  2. Nested Inequalities Among Divergence Measures

    CERN Document Server

    Taneja, Inder Jeet

    2011-01-01

    In this paper we have considered a single inequality having 11 known divergence measures. This inequality include measures like: Jeffryes-Kullback-Leiber J-divergence, Jensen-Shannon divergence (Burbea-Rao, 1982), arithmetic-geometric mean divergence (Taneja, 1995), Hellinger discrimination, symmetric chi-square divergence, triangular discrimination, etc. All these measures are well-known in the literature on Information theory and Statistics. This sequence of 11 measures also include measures due to Kumar and Johnson (2005) and Jain and Srivastava (2007). Three measures arising due to some mean divergences also appears in this inequality. Based on non-negative differences arising due to this single inequality of 11 measures, we have put more than 40 divergence measures in nested or sequential form. Idea of reverse inequalities is also introduced.

  3. Mechanisms of protein sequence divergence and incompatibility.

    Directory of Open Access Journals (Sweden)

    Alon Wellner

    Full Text Available Alignments of orthologous protein sequences convey a complex picture. Some positions are utterly conserved whilst others have diverged to variable degrees. Amongst the latter, many are non-exchangeable between extant sequences. How do functionally critical and highly conserved residues diverge? Why and how did these exchanges become incompatible within contemporary sequences? Our model is phosphoglycerate kinase (PGK, where lysine 219 is an essential active-site residue completely conserved throughout Eukaryota and Bacteria, and serine is found only in archaeal PGKs. Contemporary sequences tested exhibited complete loss of function upon exchanges at 219. However, a directed evolution experiment revealed that two mutations were sufficient for human PGK to become functional with serine at position 219. These two mutations made position 219 permissive not only for serine and lysine, but also to a range of other amino acids seen in archaeal PGKs. The identified trajectories that enabled exchanges at 219 show marked sign epistasis - a relatively small loss of function with respect to one amino acid (lysine versus a large gain with another (serine, and other amino acids. Our findings support the view that, as theoretically described, the trajectories underlining the divergence of critical positions are dominated by sign epistatic interactions. Such trajectories are an outcome of rare mutational combinations. Nonetheless, as suggested by the laboratory enabled K219S exchange, given enough time and variability in selection levels, even utterly conserved and functionally essential residues may change.

  4. A comparison of five elicitation techniques for elicitation of attributes of low involvement products

    DEFF Research Database (Denmark)

    Bech-Larsen, Tino; Nielsen, Niels Asger

    1999-01-01

    the complex elicitation of idiosyncratic attributes or simpler picking procedures, has been developed to elicitate such attributes. The purpose of the study presented here is to com-pare attributes of a low involvement product, viz. vegetable oil, elicited by five different techniques on a number...

  5. Requirements Elicitation Problems: A Literature Analysis

    Directory of Open Access Journals (Sweden)

    Bill Davey

    2015-06-01

    Full Text Available Requirements elicitation is the process through which analysts determine the software requirements of stakeholders. Requirements elicitation is seldom well done, and an inaccurate or incomplete understanding of user requirements has led to the downfall of many software projects. This paper proposes a classification of problem types that occur in requirements elicitation. The classification has been derived from a literature analysis. Papers reporting on techniques for improving requirements elicitation practice were examined for the problem the technique was designed to address. In each classification the most recent or prominent techniques for ameliorating the problems are presented. The classification allows the requirements engineer to be sensitive to problems as they arise and the educator to structure delivery of requirements elicitation training.

  6. Divergence in dialogue.

    Directory of Open Access Journals (Sweden)

    Patrick G T Healey

    Full Text Available One of the best known claims about human communication is that people's behaviour and language use converge during conversation. It has been proposed that these patterns can be explained by automatic, cross-person priming. A key test case is structural priming: does exposure to one syntactic structure, in production or comprehension, make reuse of that structure (by the same or another speaker more likely? It has been claimed that syntactic repetition caused by structural priming is ubiquitous in conversation. However, previous work has not tested for general syntactic repetition effects in ordinary conversation independently of lexical repetition. Here we analyse patterns of syntactic repetition in two large corpora of unscripted everyday conversations. Our results show that when lexical repetition is taken into account there is no general tendency for people to repeat their own syntactic constructions. More importantly, people repeat each other's syntactic constructions less than would be expected by chance; i.e., people systematically diverge from one another in their use of syntactic constructions. We conclude that in ordinary conversation the structural priming effects described in the literature are overwhelmed by the need to actively engage with our conversational partners and respond productively to what they say.

  7. Methanotrophic bacteria.

    OpenAIRE

    Hanson, R S; Hanson, T. E.

    1996-01-01

    Methane-utilizing bacteria (methanotrophs) are a diverse group of gram-negative bacteria that are related to other members of the Proteobacteria. These bacteria are classified into three groups based on the pathways used for assimilation of formaldehyde, the major source of cell carbon, and other physiological and morphological features. The type I and type X methanotrophs are found within the gamma subdivision of the Proteobacteria and employ the ribulose monophosphate pathway for formaldehy...

  8. Pepsin homologues in bacteria

    Directory of Open Access Journals (Sweden)

    Bateman Alex

    2009-09-01

    and fusion event might be very ancient indeed, preceding the divergence of bacteria and eukaryotes. It is unclear whether all the bacterial homologues are derived from horizontal gene transfer, but those from the plant symbionts probably are. The homologues from oceanic bacteria are most closely related to memapsins (or BACE-1 and BACE-2, but are so divergent that they are close to the root of the phylogenetic tree and to the division of the A1 family into two subfamilies.

  9. Stereoscopy Amplifies Emotions Elicited by Facial Expressions.

    Science.gov (United States)

    Hakala, Jussi; Kätsyri, Jari; Häkkinen, Jukka

    2015-12-01

    Mediated facial expressions do not elicit emotions as strongly as real-life facial expressions, possibly due to the low fidelity of pictorial presentations in typical mediation technologies. In the present study, we investigated the extent to which stereoscopy amplifies emotions elicited by images of neutral, angry, and happy facial expressions. The emotional self-reports of positive and negative valence (which were evaluated separately) and arousal of 40 participants were recorded. The magnitude of perceived depth in the stereoscopic images was manipulated by varying the camera base at 15, 40, 65, 90, and 115 mm. The analyses controlled for participants' gender, gender match, emotional empathy, and trait alexithymia. The results indicated that stereoscopy significantly amplified the negative valence and arousal elicited by angry expressions at the most natural (65 mm) camera base, whereas stereoscopy amplified the positive valence elicited by happy expressions in both the narrowed and most natural (15-65 mm) base conditions. Overall, the results indicate that stereoscopy amplifies the emotions elicited by mediated emotional facial expressions when the depth geometry is close to natural. The findings highlight the sensitivity of the visual system to depth and its effect on emotions. PMID:27551358

  10. Anaerobic bacteria

    Science.gov (United States)

    Brook I, Goldstein EJ. Diseases caused by non-spore forming anaerobic bacteria. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 297. Stedman's Online ...

  11. Eliciting Subjective Probabilities with Binary Lotteries

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Martínez-Correa, Jimmy; Swarthout, J. Todd

    2014-01-01

    We evaluate a binary lottery procedure for inducing risk neutral behavior in a subjective belief elicitation task. Prior research has shown this procedure to robustly induce risk neutrality when subjects are given a single risk task defined over objective probabilities. Drawing a sample from...... the same subject population, we find evidence that the binary lottery procedure also induces linear utility in a subjective probability elicitation task using the Quadratic Scoring Rule. We also show that the binary lottery procedure can induce direct revelation of subjective probabilities in subjects...

  12. Eliciting Subjective Probabilities with Binary Lotteries

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Martínez-Correa, Jimmy; Swarthout, J. Todd

    We evaluate the binary lottery procedure for inducing risk neutral behavior in a subjective belief elicitation task. Harrison, Martínez-Correa and Swarthout [2013] found that the binary lottery procedure works robustly to induce risk neutrality when subjects are given one risk task defined over...... objective probabilities. Drawing a sample from the same subject population, we find evidence that the binary lottery procedure induces linear utility in a subjective probability elicitation task using the Quadratic Scoring Rule. We also show that the binary lottery procedure can induce direct revelation...

  13. Protozoan Response to the Addition of Bacterial Predators and Other Bacteria to Soil †

    OpenAIRE

    Casida, L. E.

    1989-01-01

    Representatives of several categories of bacteria were added to soil to determine which of them might elicit responses from the soil protozoa. The various categories were nonobligate bacterial predators of bacteria, prey bacteria for these predators, indigenous bacteria that are normally present in high numbers in soil, and non-native bacteria that often find their way in large numbers into soil. The soil was incubated and the responses of the indigenous protozoa were determined by most-proba...

  14. Hyperbolic Divergence Cleaning for SPH

    CERN Document Server

    Tricco, Terrence S

    2012-01-01

    We present SPH formulations of Dedner et al's hyperbolic/parabolic divergence cleaning scheme for magnetic and velocity fields. Our implementation preserves the conservation properties of SPH which is important for stability. This is achieved by deriving an energy term for the Psi field, and imposing energy conservation on the cleaning subsystem of equations. This necessitates use of conjugate operators for divB and gradPsi in the numerical equations. For both the magnetic and velocity fields, the average divergence error in the system is reduced by an order of magnitude with our cleaning algorithm. Divergence errors in SPMHD are maintained to < 1%, even for realistic 3D applications with a corresponding gain in numerical stability. Density errors for an oscillating elliptic water drop using weakly compressible SPH are reduced by a factor of two.

  15. Sequences of Inequalities Among New Divergence Measures

    OpenAIRE

    Taneja, Inder Jeet

    2010-01-01

    There are three classical divergence measures exist in the literature on information theory and statistics. These are namely, Jeffryes-Kullback-Leiber J-divergence. Sibson-Burbea-Rao Jensen-Shannon divegernce and Taneja arithemtic-geometric mean divergence. These three measures bear an interesting relationship among each other and are based on logarithmic expressions. The divergence measures like Hellinger discrimination, symmetric chi-square divergence, and triangular discrimination are also...

  16. Generalized Symmetric Divergence Measures and Metric Spaces

    CERN Document Server

    da Costa, G A T F

    2011-01-01

    Recently, Taneja studied two one parameter generalizations of J-divergence, Jensen-Shannon divergence and Arithmetic-Geometric divergence. These two generalizations in particular contain measures like: Hellinger discrimination, symmetric chi-square divergence, and triangular discrimination. These measures are well known in the literature of Statistics and Information theory. In this paper our aim is to prove metric space properties for square root of these two symmetric generalized divergence measures.

  17. A Discussion of Usefulness and Pitfall of Elicitation and Introspection

    Institute of Scientific and Technical Information of China (English)

    陈燕娜

    2013-01-01

    Nowadays, many scholars would like to use evidence derived from elicitation and introspection in their research. Both elicitation and introspection are common methods of data collection. The essay discusses the usefulness and pitfall of elicitation and introspection. It finds out that both elicitation and introspection have their own advantages and disadvantages.

  18. Bounds on Nonsymmetric Divergence Measure in terms of Other Symmetric and Nonsymmetric Divergence Measures.

    Science.gov (United States)

    Jain, K C; Chhabra, Praphull

    2014-01-01

    Vajda (1972) studied a generalized divergence measure of Csiszar's class, so called "Chi-m divergence measure." Variational distance and Chi-square divergence are the special cases of this generalized divergence measure at m = 1 and m = 2, respectively. In this work, nonparametric nonsymmetric measure of divergence, a particular part of Vajda generalized divergence at m = 4, is taken and characterized. Its bounds are studied in terms of some well-known symmetric and nonsymmetric divergence measures of Csiszar's class by using well-known information inequalities. Comparison of this divergence with others is done. Numerical illustrations (verification) regarding bounds of this divergence are presented as well.

  19. Possible divergences in Tsallis' thermostatistics

    Science.gov (United States)

    Plastino, A.; Rocca, M. C.

    2013-12-01

    Lutsko and Boon have shown via elegant theoretical reasoning (EPL, 95 (2011) 20006), that Tsallis' thermostatistics is affected by divergence problems. We explicitly verify such fact in trying to compute the nonextensive q-partition function for the harmonic oscillator in more than two dimensions. One can see that it indeed diverges. The appeal to the so-called q-Laplace transform, where the q-exponential function plays the role of the ordinary exponential, is seen to overcome the serious problem envisaged by Lutsko and Boon.

  20. Systematic variations in divergence angle

    CERN Document Server

    Okabe, Takuya

    2012-01-01

    Practical methods for quantitative analysis of radial and angular coordinates of leafy organs of vascular plants are presented and applied to published phyllotactic patterns of various real systems from young leaves on a shoot tip to florets on a flower head. The constancy of divergence angle is borne out with accuracy of less than a degree. It is shown that apparent fluctuations in divergence angle are in large part systematic variations caused by the invalid assumption of a fixed center and/or by secondary deformations, while random fluctuations are of minor importance.

  1. Affective multimodal mirror: sensing and eliciting laughter

    NARCIS (Netherlands)

    Melder, W.A.; Truong, K.P.; Uyl, M. den; Leeuwen, D.A. van; Neerincx, M.A.; Loos, L.R.; Stock Plum, B.

    2007-01-01

    In this paper, we present a multimodal affective mirror that senses and elicits laughter. Currently, the mirror contains a vocal and a facial affect-sensing module, a component that fuses the output of these two modules to achieve a user-state assessment, a user state transition model, and a compone

  2. Distinguishing Between Social Reinforcement and Social Elicitation.

    Science.gov (United States)

    Bloom, Kathleen

    1984-01-01

    Discusses the distinction between species-typical (elicitation) and operant reinforcement interpretations of infant/adult social interaction; considers procedural and analytic components of Poulson's 1983 paper (v36 p471-89); and clarifies differences in Poulson's interpretation and the author's interpretation of the vocal conditioning studies of…

  3. Acting green elicits a literal warm glow

    NARCIS (Netherlands)

    Taufik, Danny; Bolderdijk, Jan Willem; Steg, Linda

    2015-01-01

    Environmental policies are often based on the assumption that people only act environmentally friendly if some extrinsic reward is implicated, usually money(1,2). We argue that people might also be motivated by intrinsic rewards: doing the right thing (such as acting environmentally friendly) elicit

  4. Big bacteria

    DEFF Research Database (Denmark)

    Schulz, HN; Jørgensen, BB

    2001-01-01

    , the 80 x 600 mum large Epulopiscium sp. from the gut of tropical fish, are presumably living in a very nutrient-rich medium. Many large bacteria contain numerous inclusions in the cells that reduce the volume of active cytoplasm. The most striking examples of competitive advantage from large cell size...

  5. Can packaging elements elicit consumers’ emotional responses?

    DEFF Research Database (Denmark)

    Liao, Lewis; Corsi, Armando; Lockshin, Larry;

    Emotion has been an important concept in many areas of consumer research such as judgment, decision-making and advertising. Little research has been done on emotion in packaging adopting the physiological measures used in other areas. This paper draws on past studies in advertising that measure...... emotional responses toward image, colour and font, and apply them to packaging research. The study tests the extent at which packaging can elicit consumers’ spontaneous emotional response for each of those three elements, by using skin conductance, facial electromyography (EMG) and selfassessment scales....... The results show that packaging can elicit an emotional response via different elements. The paper also raises concerns about the accuracy of using selfreport measures of emotional responses to packaging research....

  6. The Divergence of Neandertal and Modern Human Y Chromosomes.

    Science.gov (United States)

    Mendez, Fernando L; Poznik, G David; Castellano, Sergi; Bustamante, Carlos D

    2016-04-01

    Sequencing the genomes of extinct hominids has reshaped our understanding of modern human origins. Here, we analyze ∼120 kb of exome-captured Y-chromosome DNA from a Neandertal individual from El Sidrón, Spain. We investigate its divergence from orthologous chimpanzee and modern human sequences and find strong support for a model that places the Neandertal lineage as an outgroup to modern human Y chromosomes-including A00, the highly divergent basal haplogroup. We estimate that the time to the most recent common ancestor (TMRCA) of Neandertal and modern human Y chromosomes is ∼588 thousand years ago (kya) (95% confidence interval [CI]: 447-806 kya). This is ∼2.1 (95% CI: 1.7-2.9) times longer than the TMRCA of A00 and other extant modern human Y-chromosome lineages. This estimate suggests that the Y-chromosome divergence mirrors the population divergence of Neandertals and modern human ancestors, and it refutes alternative scenarios of a relatively recent or super-archaic origin of Neandertal Y chromosomes. The fact that the Neandertal Y we describe has never been observed in modern humans suggests that the lineage is most likely extinct. We identify protein-coding differences between Neandertal and modern human Y chromosomes, including potentially damaging changes to PCDH11Y, TMSB4Y, USP9Y, and KDM5D. Three of these changes are missense mutations in genes that produce male-specific minor histocompatibility (H-Y) antigens. Antigens derived from KDM5D, for example, are thought to elicit a maternal immune response during gestation. It is possible that incompatibilities at one or more of these genes played a role in the reproductive isolation of the two groups.

  7. The Divergence of Neandertal and Modern Human Y Chromosomes

    Science.gov (United States)

    Mendez, Fernando L.; Poznik, G. David; Castellano, Sergi; Bustamante, Carlos D.

    2016-01-01

    Sequencing the genomes of extinct hominids has reshaped our understanding of modern human origins. Here, we analyze ∼120 kb of exome-captured Y-chromosome DNA from a Neandertal individual from El Sidrón, Spain. We investigate its divergence from orthologous chimpanzee and modern human sequences and find strong support for a model that places the Neandertal lineage as an outgroup to modern human Y chromosomes—including A00, the highly divergent basal haplogroup. We estimate that the time to the most recent common ancestor (TMRCA) of Neandertal and modern human Y chromosomes is ∼588 thousand years ago (kya) (95% confidence interval [CI]: 447–806 kya). This is ∼2.1 (95% CI: 1.7–2.9) times longer than the TMRCA of A00 and other extant modern human Y-chromosome lineages. This estimate suggests that the Y-chromosome divergence mirrors the population divergence of Neandertals and modern human ancestors, and it refutes alternative scenarios of a relatively recent or super-archaic origin of Neandertal Y chromosomes. The fact that the Neandertal Y we describe has never been observed in modern humans suggests that the lineage is most likely extinct. We identify protein-coding differences between Neandertal and modern human Y chromosomes, including potentially damaging changes to PCDH11Y, TMSB4Y, USP9Y, and KDM5D. Three of these changes are missense mutations in genes that produce male-specific minor histocompatibility (H-Y) antigens. Antigens derived from KDM5D, for example, are thought to elicit a maternal immune response during gestation. It is possible that incompatibilities at one or more of these genes played a role in the reproductive isolation of the two groups. PMID:27058445

  8. The Divergence of Neandertal and Modern Human Y Chromosomes.

    Science.gov (United States)

    Mendez, Fernando L; Poznik, G David; Castellano, Sergi; Bustamante, Carlos D

    2016-04-01

    Sequencing the genomes of extinct hominids has reshaped our understanding of modern human origins. Here, we analyze ∼120 kb of exome-captured Y-chromosome DNA from a Neandertal individual from El Sidrón, Spain. We investigate its divergence from orthologous chimpanzee and modern human sequences and find strong support for a model that places the Neandertal lineage as an outgroup to modern human Y chromosomes-including A00, the highly divergent basal haplogroup. We estimate that the time to the most recent common ancestor (TMRCA) of Neandertal and modern human Y chromosomes is ∼588 thousand years ago (kya) (95% confidence interval [CI]: 447-806 kya). This is ∼2.1 (95% CI: 1.7-2.9) times longer than the TMRCA of A00 and other extant modern human Y-chromosome lineages. This estimate suggests that the Y-chromosome divergence mirrors the population divergence of Neandertals and modern human ancestors, and it refutes alternative scenarios of a relatively recent or super-archaic origin of Neandertal Y chromosomes. The fact that the Neandertal Y we describe has never been observed in modern humans suggests that the lineage is most likely extinct. We identify protein-coding differences between Neandertal and modern human Y chromosomes, including potentially damaging changes to PCDH11Y, TMSB4Y, USP9Y, and KDM5D. Three of these changes are missense mutations in genes that produce male-specific minor histocompatibility (H-Y) antigens. Antigens derived from KDM5D, for example, are thought to elicit a maternal immune response during gestation. It is possible that incompatibilities at one or more of these genes played a role in the reproductive isolation of the two groups. PMID:27058445

  9. Unstructured Direct Elicitation of Decision Rules

    OpenAIRE

    Ding, Min; John R. Hauser; Dong, Songting; Dzyabura, Daria; Yang, Zhilin; Su, Chenting; Gaskin, Steven

    2010-01-01

    We investigate the feasibility of unstructured direct-elicitation (UDE) of decision rules consumers use to form consideration sets. With incentives to think hard and answer truthfully, tested formats ask respondents to state non-compensatory, compensatory, or mixed rules for agents who will select a product for the respondents. In a mobile-phone study two validation tasks (one delayed 3 weeks) ask respondents to indicate which of 32 mobile phones they would consider from a fractional 4[supers...

  10. Essays on probability elicitation scoring rules

    Science.gov (United States)

    Firmino, Paulo Renato A.; dos Santos Neto, Ademir B.

    2012-10-01

    In probability elicitation exercises it has been usual to considerer scoring rules (SRs) to measure the performance of experts when inferring about a given unknown, Θ, for which the true value, θ*, is (or will shortly be) known to the experimenter. Mathematically, SRs quantify the discrepancy between f(θ) (the distribution reflecting the expert's uncertainty about Θ) and d(θ), a zero-one indicator function of the observation θ*. Thus, a remarkable characteristic of SRs is to contrast expert's beliefs with the observation θ*. The present work aims at extending SRs concepts and formulas for the cases where Θ is aleatory, highlighting advantages of goodness-of-fit and entropy-like measures. Conceptually, it is argued that besides of evaluating the personal performance of the expert, SRs may also play a role when comparing the elicitation processes adopted to obtain f(θ). Mathematically, it is proposed to replace d(θ) by g(θ), the distribution that model the randomness of Θ, and do also considerer goodness-of-fit and entropylike metrics, leading to SRs that measure the adherence of f(θ) to g(θ). The implications of this alternative perspective are discussed and illustrated by means of case studies based on the simulation of controlled experiments. The usefulness of the proposed approach for evaluating the performance of experts and elicitation processes is investigated.

  11. Hyperbolic Divergence Cleaning for SPH

    OpenAIRE

    Tricco, Terrence S.; Price, Daniel J.

    2012-01-01

    We present SPH formulations of Dedner et al's hyperbolic/parabolic divergence cleaning scheme for magnetic and velocity fields. Our implementation preserves the conservation properties of SPH which is important for stability. This is achieved by deriving an energy term for the Psi field, and imposing energy conservation on the cleaning subsystem of equations. This necessitates use of conjugate operators for divB and gradPsi in the numerical equations. For both the magnetic and velocity fields...

  12. Inflation divergence within the SADC

    OpenAIRE

    Jaunky Chandr Vishal

    2010-01-01

    This study investigates the feasibility of a monetary union in the Southern African Development Community (SADC) by testing for inflation convergence for 11 members. Quarterly data over the period 1992:3 – 2001:4 are employed. Various panel unit root tests are applied to test whether the purchasing power parity (PPP) holds. Overall, strong evidence of a unit root is found. This implies inflation divergence among the SADC members.

  13. Relative Divergence Measures and Information Inequalities

    OpenAIRE

    Taneja, Inder Jeet

    2005-01-01

    There are many information and divergence measures exist in the literature on information theory and statistics. The most famous among them are Kullback-Leiber's (1951)relative information and Jeffreys (1946) J-divergence, Information radius or Jensen difference divergence measure due to Sibson (1969) also known in the literature. Burbea and Rao (1982) has also found its applications in the literature. Taneja (1995) studied another kind of divergence measure based on arithmetic and geometric ...

  14. Genetic divergence of tomato subsamples

    Directory of Open Access Journals (Sweden)

    André Pugnal Mattedi

    2014-02-01

    Full Text Available Understanding the genetic variability of a species is crucial for the progress of a genetic breeding program and requires characterization and evaluation of germplasm. This study aimed to characterize and evaluate 101 tomato subsamples of the Salad group (fresh market and two commercial controls, one of the Salad group (cv. Fanny and another of the Santa Cruz group (cv. Santa Clara. Four experiments were conducted in a randomized block design with three replications and five plants per plot. The joint analysis of variance was performed and characteristics with significant complex interaction between control and experiment were excluded. Subsequently, the multicollinearity diagnostic test was carried out and characteristics that contributed to severe multicollinearity were excluded. The relative importance of each characteristics for genetic divergence was calculated by the Singh's method (Singh, 1981, and the less important ones were excluded according to Garcia (1998. Results showed large genetic divergence among the subsamples for morphological, agronomic and organoleptic characteristics, indicating potential for genetic improvement. The characteristics total soluble solids, mean number of good fruits per plant, endocarp thickness, mean mass of marketable fruit per plant, total acidity, mean number of unmarketable fruit per plant, internode diameter, internode length, main stem thickness and leaf width contributed little to the genetic divergence between the subsamples and may be excluded in future studies.

  15. Boiling flow through diverging microchannel

    Indian Academy of Sciences (India)

    V S Duryodhan; S G Singh; Amit Agrawal

    2013-12-01

    An experimental study of flow boiling through diverging microchannel has been carried out in this work, with the aim of understanding boiling in nonuniform cross-section microchannel. Diverging microchannel of 4° of divergence angle and 146 m hydraulic diameter (calculated at mid-length) has been employed for the present study with deionised water as working fluid. Effect of mass flux (118–1182 kg/m2-s) and heat flux (1.6–19.2 W/cm2) on single and two-phase pressure drop and average heat transfer coefficient has been studied. Concurrently, flow visualization is carried out to document the various flow regimes and to correlate the pressure drop and average heat transfer coefficient to the underlying flow regime. Four flow regimes have been identified from the measurements: bubbly, slug, slug–annular and periodic dry-out/rewetting. Variation of pressure drop with heat flux shows one maxima which corresponds to transition from bubbly to slug flow. It is shown that significantly large heat transfer coefficient (up to 107 kW/m2-K) can be attained for such systems, for small pressure drop penalty and with good flow stability.

  16. A symmetric divergence measure and its bounds

    Directory of Open Access Journals (Sweden)

    K. C. Jain

    2011-12-01

    Full Text Available A new symmetric divergence measure is proposed which is useful in comparing two probability distributions. This non-parametric measure belongs to the Csiszar's $f$ divergence class. Its properties are studied and bounds are obtained in terms of some well known divergence measures. A numerical illustration based on the probability distribution is carried out.

  17. Belief Elicitation : A Horse Race among Truth Serums

    NARCIS (Netherlands)

    Trautmann, S.T.; van de Kuilen, G.

    2011-01-01

    In survey studies, probabilistic expectations about uncertain events are typically elicited by asking respondents for their introspective beliefs. If more complex procedures are feasible, beliefs can be elicited by incentive compatible revealed preference mechanisms (“truth serums”). Various mechani

  18. Some Inequalities Among New Divergence Measures

    CERN Document Server

    Taneja, Inder Jeet

    2010-01-01

    There are three classical divergence measures exist in the literature on information theory and statistics. These are namely, Jeffryes-Kullback-Leiber J-divergence. Burbea-Rao Jensen-Shannon divegernce and Taneja arithmetic-geometric mean divergence. These three measures bear an interesting relationship among each other and are based on logarithmic expressions. The divergence measures like Hellinger discrimination symmetric chi^2 - divergence, and triangular discrimination are also known in the literature and are not based on logarithmic expressions. Past years Dragomir et al., Kumar and Johnson and Jain and Srivastava studied different kind of divergence measures. In this paper, we worked with inequalities relating these new measures with the previous know one. An idea of exponential divergence is also developed.

  19. Statistical inference based on divergence measures

    CERN Document Server

    Pardo, Leandro

    2005-01-01

    The idea of using functionals of Information Theory, such as entropies or divergences, in statistical inference is not new. However, in spite of the fact that divergence statistics have become a very good alternative to the classical likelihood ratio test and the Pearson-type statistic in discrete models, many statisticians remain unaware of this powerful approach.Statistical Inference Based on Divergence Measures explores classical problems of statistical inference, such as estimation and hypothesis testing, on the basis of measures of entropy and divergence. The first two chapters form an overview, from a statistical perspective, of the most important measures of entropy and divergence and study their properties. The author then examines the statistical analysis of discrete multivariate data with emphasis is on problems in contingency tables and loglinear models using phi-divergence test statistics as well as minimum phi-divergence estimators. The final chapter looks at testing in general populations, prese...

  20. Ultraviolet divergences and supersymmetric theories

    International Nuclear Information System (INIS)

    This article is closely related to the one by Ferrara in these same Proceedings. It deals with what is perhaps the most fascinating property of supersymmetric theories, their improved ultraviolet behavior. My aim here is to present a survey of the state of the art as of August, 1984, and a somewhat more detailed discussion of the breakdown of the superspace power-counting beyond N = 2 superfields. A method is also described for simplifying divergence calculations that uses the locality of subtracted Feynman integrals. 74 references

  1. Isolated sleep paralysis elicited by sleep interruption.

    Science.gov (United States)

    Takeuchi, T; Miyasita, A; Sasaki, Y; Inugami, M; Fukuda, K

    1992-06-01

    We elicited isolated sleep paralysis (ISP) from normal subjects by a nocturnal sleep interruption schedule. On four experimental nights, 16 subjects had their sleep interrupted for 60 minutes by forced awakening at the time when 40 minutes of nonrapid eye movement (NREM) sleep had elapsed from the termination of rapid eye movement (REM) sleep in the first or third sleep cycle. This schedule produced a sleep onset REM period (SOREMP) after the interruption at a high rate of 71.9%. We succeeded in eliciting six episodes of ISP in the sleep interruptions performed (9.4%). All episodes of ISP except one occurred from SOREMP, indicating a close correlation between ISP and SOREMP. We recorded verbal reports about ISP experiences and recorded the polysomnogram (PSG) during ISP. All of the subjects with ISP experienced inability to move and were simultaneously aware of lying in the laboratory. All but one reported auditory/visual hallucinations and unpleasant emotions. PSG recordings during ISP were characterized by a REM/W stage dissociated state, i.e. abundant alpha electroencephalographs and persistence of muscle atonia shown by the tonic electromyogram. Judging from the PSG recordings, ISP differs from other dissociated states such as lucid dreaming, nocturnal panic attacks and REM sleep behavior disorders. We compare some of the sleep variables between ISP and non-ISP nights. We also discuss the similarities and differences between ISP and sleep paralysis in narcolepsy.

  2. Isolated sleep paralysis elicited by sleep interruption.

    Science.gov (United States)

    Takeuchi, T; Miyasita, A; Sasaki, Y; Inugami, M; Fukuda, K

    1992-06-01

    We elicited isolated sleep paralysis (ISP) from normal subjects by a nocturnal sleep interruption schedule. On four experimental nights, 16 subjects had their sleep interrupted for 60 minutes by forced awakening at the time when 40 minutes of nonrapid eye movement (NREM) sleep had elapsed from the termination of rapid eye movement (REM) sleep in the first or third sleep cycle. This schedule produced a sleep onset REM period (SOREMP) after the interruption at a high rate of 71.9%. We succeeded in eliciting six episodes of ISP in the sleep interruptions performed (9.4%). All episodes of ISP except one occurred from SOREMP, indicating a close correlation between ISP and SOREMP. We recorded verbal reports about ISP experiences and recorded the polysomnogram (PSG) during ISP. All of the subjects with ISP experienced inability to move and were simultaneously aware of lying in the laboratory. All but one reported auditory/visual hallucinations and unpleasant emotions. PSG recordings during ISP were characterized by a REM/W stage dissociated state, i.e. abundant alpha electroencephalographs and persistence of muscle atonia shown by the tonic electromyogram. Judging from the PSG recordings, ISP differs from other dissociated states such as lucid dreaming, nocturnal panic attacks and REM sleep behavior disorders. We compare some of the sleep variables between ISP and non-ISP nights. We also discuss the similarities and differences between ISP and sleep paralysis in narcolepsy. PMID:1621022

  3. Rumen bacteria

    International Nuclear Information System (INIS)

    The rumen is the most extensively studied gut community and is characterized by its high population density, wide diversity and complexity of interactions. This complex, mixed microbial culture is comprised of prokaryote organisms including methane-producing archaebacteria, eukaryote organisms, such as ciliate and flagellate protozoa, anaerobic phycomycete fungi and bacteriophage. Bacteria are predominant (up to 1011 viable cells per g comprising 200 species) but a variety of ciliate protozoa occur widely (104-106/g distributed over 25 genera). The anaerobic fungi are also widely distributed (zoospore population densities of 102-104/g distributed over 5 genera). The occurrence of bacteriophage is well documented (107-109 particles/g). This section focuses primarily on the widely used methods for the cultivation and the enumeration of rumen microbes, especially bacteria, which grow under anaerobic conditions. Methods that can be used to measure hydrolytic enzymes (cellulases, xylanases, amylases and proteinases) are also described, along with cell harvesting and fractionation procedures. Brief reference is also made to fungi and protozoa, but detailed explanations for culturing and enumerating these microbes is presented in Chapters 2.4 and 2.5

  4. Role of Heterotrophic Bacteria in Marine Ecological Processes

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, N.

    of Heterotrophic Bacteria in Marine Ecological Processes N. Ramaiah National Institute of Oceanography, Dona Paula, Goa 403 004, INDIA Introduction To the students of biology, the term bacterium elicits smallness, abundance, invidiousness, and completeness....1 to 4 ?m in length, the abilities of decomposing innumerable organic molecules and several xenobiotics bring heterotrophic bacteria to the centre-stage of nutrient cycling within the earth?s ecosystems. All the world oceans are one contiguous water body...

  5. Needs Elicitation for Novel Pervasive Healthcare Technology

    DEFF Research Database (Denmark)

    Thorpe, Julia Rosemary; Forchhammer, B. H.; Maier, Anja

    2016-01-01

    It is widely accepted that engaging with end-users to elicit their needs is beneficial when designing a new artefact. This can be particularly challenging, however, when end-users are limited in their ability to provide input. When there is broad variation in users' needs, a further challenge...... is to include the large number of users required to represent the entire population. Failure to do so may lead to a solution that is over specialised to fit the needs of only a small subset of users. Both challenges are common in healthcare applications in which the end-user is also care recipient (or patient......). What if instead of trying to engage vastly many users in design activities, we could hear the voice of the patient by tapping into existing channels within the health care service system? Many interactions between healthcare providers and patients involve knowledge transfer. Observing these could...

  6. DISSIPATIVE DIVERGENCE OF RESONANT ORBITS

    Energy Technology Data Exchange (ETDEWEB)

    Batygin, Konstantin [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Morbidelli, Alessandro, E-mail: kbatygin@gps.caltech.edu [Departement Cassiopee, Universite de Nice-Sophia Antipolis, Observatoire de la Cote d' Azur, F-06304 Nice (France)

    2013-01-01

    A considerable fraction of multi-planet systems discovered by the observational surveys of extrasolar planets reside in mild proximity to first-order mean-motion resonances. However, the relative remoteness of such systems from nominal resonant period ratios (e.g., 2:1, 3:2, and 4:3) has been interpreted as evidence for lack of resonant interactions. Here, we show that a slow divergence away from exact commensurability is a natural outcome of dissipative evolution and demonstrate that libration of critical angles can be maintained tens of percent away from nominal resonance. We construct an analytical theory for the long-term dynamical evolution of dissipated resonant planetary pairs and confirm our calculations numerically. Collectively, our results suggest that a significant fraction of the near-commensurate extrasolar planets are in fact resonant and have undergone significant dissipative evolution.

  7. Guises and disguises of quadratic divergences

    Energy Technology Data Exchange (ETDEWEB)

    Cherchiglia, A.L., E-mail: adriano@fisica.ufmg.br [Departamento de Física, ICEx, Universidade Federal de Minas Gerais, P.O. BOX 702, 30.161-970, Belo Horizonte, MG (Brazil); Vieira, A.R., E-mail: arvieira@fisica.ufmg.br [Departamento de Física, ICEx, Universidade Federal de Minas Gerais, P.O. BOX 702, 30.161-970, Belo Horizonte, MG (Brazil); Hiller, Brigitte, E-mail: brigitte@teor.fis.uc.pt [Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-516 Coimbra (Portugal); Baêta Scarpelli, A.P., E-mail: scarpelli.apbs@dpf.gov.br [Setor Técnico-Científico, Departamento de Polícia Federal, Rua Hugo D’Antola, 95 - Lapa, São Paulo (Brazil); Sampaio, Marcos, E-mail: marcos.sampaio@durham.ac.uk [Departamento de Física, ICEx, Universidade Federal de Minas Gerais, P.O. BOX 702, 30.161-970, Belo Horizonte, MG (Brazil); Centre for Particle Theory, Department of Mathematical Sciences, Durham University, South Road Durham DH1 3LE (United Kingdom)

    2014-12-15

    In this contribution, we present a new perspective on the control of quadratic divergences in quantum field theory, in general, and in the Higgs naturalness problem, in particular. Our discussion is essentially based on an approach where UV divergences are parameterized, after being reduced to basic divergent integrals (BDI) in one internal momentum, as functions of a cutoff and a renormalization group scale λ. We illustrate our proposal with well-known examples, such as the gluon vacuum self energy of QCD and the Higgs decay in two photons within this approach. We also discuss frameworks in effective low-energy QCD models, where quadratic divergences are indeed fundamental.

  8. Mucosal Vaccination and Therapy with Genetically Modified Lactic Acid Bacteria

    NARCIS (Netherlands)

    Wells, J.

    2011-01-01

    Lactic acid bacteria (LAB) have proved to be effective mucosal delivery vehicles that overcome the problem of delivering functional proteins to the mucosal tissues. By the intranasal route, both live and killed LAB vaccine strains have been shown to elicit mucosal and systemic immune responses that

  9. Inequalities among New Non-Symmetric Divergence and Chi-Square Divergence Measure

    OpenAIRE

    Ram Naresh Saraswat

    2015-01-01

    Information divergence measures and their bounds are well known in the literature of Information Theory. In this research paper, we shall consider a new non-symmetric information divergence measure. Upper and lower bounds of new non-symmetric divergence measure are also considered.

  10. Inequalities among New Non-Symmetric Divergence and Chi-Square Divergence Measure

    Directory of Open Access Journals (Sweden)

    Ram Naresh Saraswat

    2015-12-01

    Full Text Available Information divergence measures and their bounds are well known in the literature of Information Theory. In this research paper, we shall consider a new non-symmetric information divergence measure. Upper and lower bounds of new non-symmetric divergence measure are also considered.

  11. Expert elicitation of population-level effects of disturbance

    Science.gov (United States)

    Fleishman, Erica; Burgman, Mark; Runge, Michael C.; Schick, Robert S; Krauss, Scott; Popper, Arthur N.; Hawkins, Anthony

    2016-01-01

    Expert elicitation is a rigorous method for synthesizing expert knowledge to inform decision making and is reliable and practical when field data are limited. We evaluated the feasibility of applying expert elicitation to estimate population-level effects of disturbance on marine mammals. Diverse experts estimated parameters related to mortality and sublethal injury of North Atlantic right whales (Eubalaena glacialis). We are now eliciting expert knowledge on the movement of right whales among geographic regions to parameterize a spatial model of health. Expert elicitation complements methods such as simulation models or extrapolations from other species, sometimes with greater accuracy and less uncertainty.

  12. Expert Elicitation of Population-Level Effects of Disturbance.

    Science.gov (United States)

    Fleishman, Erica; Burgman, Mark; Runge, Michael C; Schick, Robert S; Kraus, Scott

    2016-01-01

    Expert elicitation is a rigorous method for synthesizing expert knowledge to inform decision making and is reliable and practical when field data are limited. We evaluated the feasibility of applying expert elicitation to estimate population-level effects of disturbance on marine mammals. Diverse experts estimated parameters related to mortality and sublethal injury of North Atlantic right whales (Eubalaena glacialis). We are now eliciting expert knowledge on the movement of right whales among geographic regions to parameterize a spatial model of health. Expert elicitation complements methods such as simulation models or extrapolations from other species, sometimes with greater accuracy and less uncertainty. PMID:26610972

  13. Power Divergences in Overlapping Wilson Lines

    OpenAIRE

    Berwein, Matthias

    2014-01-01

    We discuss the divergence structure of Wilson line operators with partially overlapping segments on the basis of the cyclic Wilson loop as an explicit example. The generalized exponentiation theorem is used to show the exponentiation and factorization of power divergences for certain linear combinations of associated loop functions.

  14. Power divergences in overlapping Wilson lines

    Science.gov (United States)

    Berwein, Matthias

    2016-01-01

    We discuss the divergence structure of Wilson line operators with partially overlapping segments on the basis of the cyclic Wilson loop as an explicit example. The generalized exponentiation theorem is used to show the exponentiation and factorization of power divergences for certain linear combinations of associated loop functions.

  15. Duality of Maximum Entropy and Minimum Divergence

    Directory of Open Access Journals (Sweden)

    Shinto Eguchi

    2014-06-01

    Full Text Available We discuss a special class of generalized divergence measures by the use of generator functions. Any divergence measure in the class is separated into the difference between cross and diagonal entropy. The diagonal entropy measure in the class associates with a model of maximum entropy distributions; the divergence measure leads to statistical estimation via minimization, for arbitrarily giving a statistical model. The dualistic relationship between the maximum entropy model and the minimum divergence estimation is explored in the framework of information geometry. The model of maximum entropy distributions is characterized to be totally geodesic with respect to the linear connection associated with the divergence. A natural extension for the classical theory for the maximum likelihood method under the maximum entropy model in terms of the Boltzmann-Gibbs-Shannon entropy is given. We discuss the duality in detail for Tsallis entropy as a typical example.

  16. Acting green elicits a literal warm glow

    Science.gov (United States)

    Taufik, Danny; Bolderdijk, Jan Willem; Steg, Linda

    2015-01-01

    Environmental policies are often based on the assumption that people only act environmentally friendly if some extrinsic reward is implicated, usually money. We argue that people might also be motivated by intrinsic rewards: doing the right thing (such as acting environmentally friendly) elicits psychological rewards in the form of positive feelings, a phenomenon known as warm glow. Given the fact that people's psychological state may affect their thermal state, we expected that this warm glow could express itself quite literally: people who act environmentally friendly may perceive the temperature to be higher. In two studies, we found that people who learned they acted environmentally friendly perceived a higher temperature than people who learned they acted environmentally unfriendly. The underlying psychological mechanism pertains to the self-concept: learning you acted environmentally friendly signals to yourself that you are a good person. Together, our studies show that acting environmentally friendly can be psychologically rewarding, suggesting that appealing to intrinsic rewards can be an alternative way to encourage pro-environmental actions.

  17. Introducing Forum Theatre to Elicit and Advocate Children's Views

    Science.gov (United States)

    Hammond, Nick

    2013-01-01

    Eliciting and advocating the voice of the child remains at the heart of international political agenda and also remains a central role for educational psychologists (EPs). Previous research indicates that EPs tend to use language-based methods for eliciting and advocating views of children. However, these approaches are often limited. Taking a…

  18. Belief elicitation in experiments: Is there a hedging problem?

    DEFF Research Database (Denmark)

    Blanco, Mariana; Engelmann, Dirk; Koch, Alexander;

    2010-01-01

    Belief-elicitation experiments usually reward accuracy of stated beliefs in addition to payments for other decisions. But this allows risk-averse subjects to hedge with their stated beliefs against adverse outcomes of the other decisions. So can we trust the existing belief-elicitation results? A...

  19. Elicited Emotions and Cognitive Functioning in Preschool Children

    Science.gov (United States)

    Blau, Rivka; Klein, Pnina S.

    2010-01-01

    In this study, the effects of eliciting positive and negative emotions on various cognitive functions of four- to five-year-old preschool children were examined. Emotions were elicited through presentations of "happy" and "sad" video clips, before the children performed the cognitive tasks. Behavioural (facial expressions) and physiological (heart…

  20. Anger elicitation in Tonga and Germany: The impact of culture on cognitive determinants of emotions

    Directory of Open Access Journals (Sweden)

    Andrea eBender

    2012-10-01

    Full Text Available The cognitive appraisal of an event is crucial for the elicitation and differentiation of emotions, and causal attributions are an integral part of this process. In an interdisciplinary project comparing Tonga and Germany, we examined how cultural differences in attribution tendencies affect emotion assessment and elicitation. Data on appraising causality and responsibility and on emotional responses were collected through questionnaires based on experimentally designed vignettes, and were related to culture-specific values, norms, and the prevailing self-concept. The experimental data support our hypothesis that—driven by culturally defined self-concepts and corresponding attribution tendencies—members of the two cultures cognitively appraise events in diverging manners and consequently differ in their emotional responses. Ascription of responsibility to self and/or circumstances, in line with a more interdependent self-concept, co-varies with higher ratings of shame, guilt and sadness, whereas ascription of responsibility to others, in line with a less interdependent self-concept, co-varies with higher ratings of anger. These findings support the universal contingency hypothesis and help to explain cultural differences in this domain on a fine-grained level.

  1. A Redox 2-Cys Mechanism Regulates the Catalytic Activity of Divergent Cyclophilins1[W

    Science.gov (United States)

    Campos, Bruna Medéia; Sforça, Mauricio Luis; Ambrosio, Andre Luis Berteli; Domingues, Mariane Noronha; Brasil de Souza, Tatiana de Arruda Campos; Barbosa, João Alexandre Ribeiro Gonçalvez; Leme, Adriana Franco Paes; Perez, Carlos Alberto; Whittaker, Sara Britt-Marie; Murakami, Mario Tyago; Zeri, Ana Carolina de Matos; Benedetti, Celso Eduardo

    2013-01-01

    The citrus (Citrus sinensis) cyclophilin CsCyp is a target of the Xanthomonas citri transcription activator-like effector PthA, required to elicit cankers on citrus. CsCyp binds the citrus thioredoxin CsTdx and the carboxyl-terminal domain of RNA polymerase II and is a divergent cyclophilin that carries the additional loop KSGKPLH, invariable cysteine (Cys) residues Cys-40 and Cys-168, and the conserved glutamate (Glu) Glu-83. Despite the suggested roles in ATP and metal binding, the functions of these unique structural elements remain unknown. Here, we show that the conserved Cys residues form a disulfide bond that inactivates the enzyme, whereas Glu-83, which belongs to the catalytic loop and is also critical for enzyme activity, is anchored to the divergent loop to maintain the active site open. In addition, we demonstrate that Cys-40 and Cys-168 are required for the interaction with CsTdx and that CsCyp binds the citrus carboxyl-terminal domain of RNA polymerase II YSPSAP repeat. Our data support a model where formation of the Cys-40-Cys-168 disulfide bond induces a conformational change that disrupts the interaction of the divergent and catalytic loops, via Glu-83, causing the active site to close. This suggests a new type of allosteric regulation in divergent cyclophilins, involving disulfide bond formation and a loop-displacement mechanism. PMID:23709667

  2. The constancy of gene conservation across divergent bacterial orders

    Directory of Open Access Journals (Sweden)

    Ackermann Martin

    2009-01-01

    Full Text Available Abstract Background Orthologous genes are frequently presumed to perform similar functions. However, outside of model organisms, this is rarely tested. One means of inferring changes in function is if there are changes in the level of gene conservation and selective constraint. Here we compare levels of gene conservation across three bacterial groups to test for changes in gene functionality. Findings The level of gene conservation for different orthologous genes is highly correlated across clades, even for highly divergent groups of bacteria. These correlations do not arise from broad differences in gene functionality (e.g. informational genes vs. metabolic genes, but instead seem to result from very specific differences in gene function. Furthermore, these functional differences appear to be maintained over very long periods of time. Conclusion These results suggest that even over broad time scales, most bacterial genes are under a nearly constant level of purifying selection, and that bacterial evolution is thus dominated by selective and functional stasis.

  3. Seven Means, Generalized Triangular Discrimination, and Generating Divergence Measures

    OpenAIRE

    Inder Jeet Taneja

    2013-01-01

    Jensen-Shannon, J-divergence and Arithmetic-Geometric mean divergences are three classical divergence measures known in the information theory and statistics literature. These three divergence measures bear interesting inequality among the three non-logarithmic measures known as triangular discrimination, Hellingar’s divergence and symmetric chi-square divergence. However, in 2003, Eve studied seven means from a geometrical point of view, which are Harmonic, Geometric, Arithmetic, Heronian, C...

  4. Generalized Non-Symmetric Divergence Measures and Inequalities

    OpenAIRE

    Taneja, Inder Jeet; Kumar, Pranesh

    2005-01-01

    In this paper we consider one parameter generalizations of some non - symmetric divergence measures. Measures are \\textit{relative information}, $\\chi ^2 - $\\textit{divergence}, \\textit{relative J-divergence}, \\textit{relative Jensen-Shannon divergence}and \\textit{relative arithmetic and geometric divergence}. All the generalizations considered can be written as particular cases of Csisz\\'{a}r \\textit{f-divergence}. By conditioning the probability distributions, relationships among the \\texti...

  5. Stora's fine notion of divergent amplitudes

    CERN Document Server

    Várilly, Joseph C

    2016-01-01

    Stora and coworkers refined the notion of divergent quantum amplitude, somewhat upsetting the standard power-counting recipe. This unexpectedly clears the way to new prototypes for free and interacting field theories of bosons of any mass and spin.

  6. Zero modes and divergence of entanglement entropy

    CERN Document Server

    Mallayya, Krishnanand; Shankaranarayanan, S; Padmanabhan, T

    2014-01-01

    We investigate the cause of the divergence of the entanglement entropy for the free scalar fields in $(1+1)$ and $(D + 1)$ dimensional space-times. In a canonically equivalent set of variables, we show explicitly that the divergence in the entanglement entropy in $(1 + 1)-$ dimensions is due to the accumulation of large number of near-zero frequency modes as opposed to the commonly held view of divergence having UV origin. The feature revealing the divergence in zero modes is related to the observation that the entropy is invariant under a hidden scaling transformation even when the Hamiltonian is not. We discuss the role of dispersion relations and the dimensionality of the space-time on the behavior of entanglement entropy.

  7. Generalized Symmetric Divergence Measures and the Probability of Error

    CERN Document Server

    Taneja, Inder Jeet

    2011-01-01

    There are three classical divergence measures exist in the literature on information theory and statistics. These are namely, Jeffryes-Kullback-Leiber J-divergence. Sibson-Burbea-Rao Jensen-Shannon divegernce and Taneja Arithemtic-Geometric divergence}. These three measures bear an interesting relationship among each other. The divergence measures like Hellinger discrimination, symmetric chi-square divergence, and triangular discrimination are also known in the literature. In this paper our aim is to give connections of generalized divergences of J-divergence and Jensen-Shannon divergence with probability of error.

  8. Evaluation of a Fluorescent Lectin-Based Staining Technique for Some Acidophilic Mining Bacteria

    OpenAIRE

    Fife, Dee Jay; Bruhn, Debby F.; Miller, Karen S.; Stoner, Daphne L.

    2000-01-01

    A fluorescence-labeled wheat germ agglutinin staining technique (R. K. Sizemore et al., Appl. Environ. Microbiol. 56:2245–2247, 1990) was modified and found to be effective for staining gram-positive, acidophilic mining bacteria. Bacteria identified by others as being gram positive through 16S rRNA sequence analyses, yet clustering near the divergence of that group, stained weakly. Gram-negative bacteria did not stain. Background staining of environmental samples was negligible, and pyrite an...

  9. Spoonerisms as Sequencer Conflicts: Evidence from Artifically Elicited Errors

    Science.gov (United States)

    Baars, Bernard J.; Motley, Michael T.

    1976-01-01

    Presents evidence that spoonerisms result from a conflict in word sequencing that carries through to phoneme sequencing, and in the process illustrates the use of some techniques for the experimental elicitation of spoonerisms. (Author/RK)

  10. CCSI Risk Estimation: An Application of Expert Elicitation

    Energy Technology Data Exchange (ETDEWEB)

    Engel, David W.; Dalton, Angela C.

    2012-10-01

    The Carbon Capture Simulation Initiative (CCSI) is a multi-laboratory simulation-driven effort to develop carbon capture technologies with the goal of accelerating commercialization and adoption in the near future. One of the key CCSI technical challenges is representing and quantifying the inherent uncertainty and risks associated with developing, testing, and deploying the technology in simulated and real operational settings. To address this challenge, the CCSI Element 7 team developed a holistic risk analysis and decision-making framework. The purpose of this report is to document the CCSI Element 7 structured systematic expert elicitation to identify additional risk factors. We review the significance of and established approaches to expert elicitation, describe the CCSI risk elicitation plan and implementation strategies, and conclude by discussing the next steps and highlighting the contribution of risk elicitation toward the achievement of the overarching CCSI objectives.

  11. Elicitation of preferences for improvements in ostomy pouches

    DEFF Research Database (Denmark)

    Bonnichsen, Ole

    This paper attempts to examine and measure ostomates’ preferences for improvements in ostomy pouches. Described are the study design, elicitation procedure and resulting preference structure of the Swedish ostomate sample. The method used to elicit the preferences is a Discrete Choice Experiment ......, emphasis should be placed on this attribute when decisions are made as to the allocation of scarce health care resources within research and development aimed at improving ostomy pouches.......This paper attempts to examine and measure ostomates’ preferences for improvements in ostomy pouches. Described are the study design, elicitation procedure and resulting preference structure of the Swedish ostomate sample. The method used to elicit the preferences is a Discrete Choice Experiment...... (DCE), where respondents are asked to choose between alternatives in choice sets. Each alternative is comprised of a number of attributes relating to the adhesive, filter and flexibility of ostomy pouches. The choice between alternatives made by the respondent implies an implicit trade-off between...

  12. Elicitation of normative and fairness judgments: Do incentives matter?

    OpenAIRE

    Štěpán Veselý

    2015-01-01

    Krupka and Weber (2013) introduce an incentive-compatible coordination game as an alternative method for elicitation of normative judgments. I show, however, that people provide virtually the same responses in incentivized and non-incentivized versions of the Krupka-Weber game. Besides ratings of social appropriateness, I also elicit ratings of fairness of all possible offers in an ultimatum game. Ratings of social appropriateness and fairness are similar for low offers (bel...

  13. Utilizing online serious games to facilitate distributed requirements elicitation

    OpenAIRE

    Ghanbari, Hadi; Similä, Jouni; Markkula, Jouni

    2015-01-01

    Requirements elicitation is one of the most important and challenging activities in software development projects. A variety of challenges related to requirements elicitation are reported in the literature, of which the lack of proper communication and knowledge transfer between software stakeholders are among the most important. Communication and knowledge transfer are becoming even bigger challenges with the current increase in globally distributed software development projects due to the t...

  14. Eliciting Multi-touch Selection Gestures for Interactive Data Graphics

    OpenAIRE

    Willett, Wesley; Lan, Qi; Isenberg, Petra

    2014-01-01

    International audience; We report the results of a study in which we elicited selection gestures for multi-touch data graphics. The selection of data items is a common and extremely important form of interaction with data graphics, and serves as the basis for many other data interaction techniques. However, interactive charting tools for multi-touch displays typically only provide dedicated multi-touch gestures for single-point selection or zooming. Our study used gesture elicitation to explo...

  15. The new vaccines: building viruses that elicit antitumor immunity

    OpenAIRE

    Restifo, Nicholas P

    1996-01-01

    Whereas cancer cells are poor immunogens, some viruses are capable of eliciting powerful and lifelong immunity. Recombinant viruses and plasmid DNA encoding tumor-associated antigens can elicit powerful and specific immune responses that can be enhanced by the use of cytokines and costimulatory molecules. These immune responses have destroyed growing tumor cells in experimental animal models. For the first time, immunotherapeutic strategies that employ recombinant viruses are being tested in ...

  16. Bacteria isolated from amoebae/bacteria consortium

    Science.gov (United States)

    Tyndall, Richard L.

    1995-01-01

    New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

  17. NVC Based Model for Selecting Effective Requirement Elicitation Technique

    Directory of Open Access Journals (Sweden)

    Md. Rizwan Beg

    2012-10-01

    Full Text Available Requirement Engineering process starts from gathering of requirements i.e.; requirements elicitation. Requirementselicitation (RE is the base building block for a software project and has very high impact onsubsequent design and builds phases as well. Accurately capturing system requirements is the major factorin the failure of most of software projects. Due to the criticality and impact of this phase, it is very importantto perform the requirements elicitation in no less than a perfect manner. One of the most difficult jobsfor elicitor is to select appropriate technique for eliciting the requirement. Interviewing and Interactingstakeholder during Elicitation process is a communication intensive activity involves Verbal and Nonverbalcommunication (NVC. Elicitor should give emphasis to Non-verbal communication along with verbalcommunication so that requirements recorded more efficiently and effectively. In this paper we proposea model in which stakeholders are classified by observing non-verbal communication and use it as a basefor elicitation technique selection. We also propose an efficient plan for requirements elicitation which intendsto overcome on the constraints, faced by elicitor.

  18. Properties of classical and quantum Jensen-Shannon divergence

    NARCIS (Netherlands)

    Briët, J.; Harremoës, P.

    2009-01-01

    Jensen-Shannon divergence (JD) is a symmetrized and smoothed version of the most important divergence measure of information theory, Kullback divergence. As opposed to Kullback divergence it determines in a very direct way a metric; indeed, it is the square of a metric. We consider a family of diver

  19. Bleach vs. Bacteria

    Science.gov (United States)

    ... Articles | Inside Life Science Home Page Bleach vs. Bacteria By Sharon Reynolds Posted April 2, 2014 Your ... hypochlorous acid to help kill invading microbes, including bacteria. Researchers funded by the National Institutes of Health ...

  20. Bounded divergence measures based on Bhattacharyya coefficient

    CERN Document Server

    Roman, Ahmed; Shastry, Mahesh C

    2012-01-01

    We introduce a new class of entropy based measure for calculating the distance between probability distributions. Our measure, called the bounded Bhattacharyya distance (BBD) is based on the Bhattacharyya distance, and is symmetric, positive semi-definite, and bounded. Unlike the Kullback-Leibler divergence, BBD does not require probability density functions to be absolutely continuous with respect to each other. We show that BBD belongs to the class of Csiszars f-divergences and derive certain relationship between BBD and well known measures such as Bhattacharyya, Hellinger and Jensen-Shannon divergence. Bounds on Bayesian error probability are established with BBD measure. The second derivative of BBD is proportional to the Fishers information. For distributions with vector valued parameters of the same family, the curvature matrix can be used to get the Rao's geodesic distance between parametric distributions.

  1. Diverging expectations in buyer-seller relationships

    DEFF Research Database (Denmark)

    Andersen, Poul Houman; Christensen, Poul Rind; Damgaard, Torben

    2009-01-01

    Many firms assume that outsourcing partnerships may allow them to strengthen their overall competitiveness. Lured by its intuitive appeal, several enter into such partnerships, only to realize that they represent a marginal rather than a magical solution to their quest for increasing market...... performance. An important reason for this is the diverging beliefs and expectations held by both parties in the buyer-seller dyad. The purpose of this contribution is to develop a framework for understanding the divergences in expectations and relationship norms in cross-cultural business relationships among...... SMEs. We discuss four relational expectations derived from the B2B literature on relational norms for addressing these divergences: Quality, frequency and scope of communication, role specifications and coordination of work nature of planning horizons, and trustworthiness and link these to relationship...

  2. Vibhakti Divergence between Sanskrit and Hindi

    Science.gov (United States)

    Shukla, Preeti; Shukl, Devanand; Kulkarni, Amba

    Translation divergence at various levels between languages arises due to the different conventions followed by different languages for coding the information of grammatical relations. Though Sanskrit and Hindi belong to the same Indo-Aryan family and structurally as well as lexically Hindi inherits a lot from Sanskrit, yet divergences are observed at the level of function words such as vibhaktis. Pāṇini in his Aṣṭādhyāyī has assigned a default vibhakti to kārakas alongwith many scopes for exceptions. He handles these exceptions either by imposing a new kāraka role or by assigning a special vibhakti. However, these methods are not acceptable in Hindi in toto. Based on the nature of deviation, we propose seven cases of divergences in this paper.

  3. An Exponential Regulator for Rapidity Divergences

    CERN Document Server

    Li, Ye; Zhu, Hua Xing

    2016-01-01

    Finding an efficient and compelling regularization of soft and collinear degrees of freedom at the same invariant mass scale, but separated in rapidity is a persistent problem in high-energy factorization. In the course of a calculation, one encounters divergences unregulated by dimensional regularization, often called rapidity divergences. Once regulated, a general framework exists for their renormalization, the rapidity renormalization group (RRG), leading to fully resummed calculations of transverse momentum (to the jet axis) sensitive quantities. We examine how this regularization can be implemented via a multi-differential factorization of the soft-collinear phase-space, leading to an (in principle) alternative non-perturbative regularization of rapidity divergences. As an example, we examine the fully-differential factorization of a color singlet's momentum spectrum in a hadron-hadron collision at threshold. We show how this factorization acts as a mother theory to both traditional threshold and transve...

  4. Bacteria and lignin degradation

    Institute of Scientific and Technical Information of China (English)

    Jing LI; Hongli YUAN; Jinshui YANG

    2009-01-01

    Lignin is both the most abundant aromatic (phenolic) polymer and the second most abundant raw material.It is degraded and modified by bacteria in the natural world,and bacteria seem to play a leading role in decomposing lignin in aquatic ecosystems.Lignin-degrading bacteria approach the polymer by mechanisms such as tunneling,erosion,and cavitation.With the advantages of immense environmental adaptability and biochemical versatility,bacteria deserve to be studied for their ligninolytic potential.

  5. Generalized Symmetric Divergence Measures and the Probability of Error

    OpenAIRE

    Taneja, Inder Jeet

    2011-01-01

    There are three classical divergence measures exist in the literature on information theory and statistics. These are namely, Jeffryes-Kullback-Leiber J-divergence. Sibson-Burbea-Rao Jensen-Shannon divegernce and Taneja Arithmetic-Geometric divergence. These three measures bear an interesting relationship among each other. The divergence measures like Hellinger discrimination, symmetric chi-square divergence, and triangular discrimination are also known in the literature. In this paper, we ha...

  6. Temporary divergence paralysis in viral meningitis.

    Science.gov (United States)

    Bakker, Stef L M; Gan, Ivan M

    2008-06-01

    A 43-year-old woman who reported diplopia and headache was found to have comitant esotropia at distance fixation and normal alignment at reading distance (divergence paralysis). Eye movement, including abduction, was normal as was the rest of the neurologic examination. Brain MRI was normal. Lumbar puncture showed an elevated opening pressure and a cerebrospinal fluid formula consistent with viral meningitis. The patient was treated with intravenous fluids and analgesics and with a temporary prism to alleviate diplopia. Within 3 weeks, she had fully recovered. This is the first report of divergence palsy in viral meningitis.

  7. Interactions between the microbiota and pathogenic bacteria in the gut.

    Science.gov (United States)

    Bäumler, Andreas J; Sperandio, Vanessa

    2016-07-01

    The microbiome has an important role in human health. Changes in the microbiota can confer resistance to or promote infection by pathogenic bacteria. Antibiotics have a profound impact on the microbiota that alters the nutritional landscape of the gut and can lead to the expansion of pathogenic populations. Pathogenic bacteria exploit microbiota-derived sources of carbon and nitrogen as nutrients and regulatory signals to promote their own growth and virulence. By eliciting inflammation, these bacteria alter the intestinal environment and use unique systems for respiration and metal acquisition to drive their expansion. Unravelling the interactions between the microbiota, the host and pathogenic bacteria will produce strategies for manipulating the microbiota against infectious diseases. PMID:27383983

  8. Interactions between the microbiota and pathogenic bacteria in the gut.

    Science.gov (United States)

    Bäumler, Andreas J; Sperandio, Vanessa

    2016-07-06

    The microbiome has an important role in human health. Changes in the microbiota can confer resistance to or promote infection by pathogenic bacteria. Antibiotics have a profound impact on the microbiota that alters the nutritional landscape of the gut and can lead to the expansion of pathogenic populations. Pathogenic bacteria exploit microbiota-derived sources of carbon and nitrogen as nutrients and regulatory signals to promote their own growth and virulence. By eliciting inflammation, these bacteria alter the intestinal environment and use unique systems for respiration and metal acquisition to drive their expansion. Unravelling the interactions between the microbiota, the host and pathogenic bacteria will produce strategies for manipulating the microbiota against infectious diseases.

  9. Differences in TCDD-elicited gene expression profiles in human HepG2, mouse Hepa1c1c7 and rat H4IIE hepatoma cells

    Directory of Open Access Journals (Sweden)

    Burgoon Lyle D

    2011-04-01

    Full Text Available Abstract Background 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD is an environmental contaminant that elicits a broad spectrum of toxic effects in a species-specific manner. Current risk assessment practices routinely extrapolate results from in vivo and in vitro rodent models to assess human risk. In order to further investigate the species-specific responses elicited by TCDD, temporal gene expression responses in human HepG2, mouse Hepa1c1c7 and rat H4IIE cells were compared. Results Microarray analysis identified a core set of conserved gene expression responses across species consistent with the role of AhR in mediating adaptive metabolic responses. However, significant species-specific as well as species-divergent responses were identified. Computational analysis of the regulatory regions of species-specific and -divergent responses suggests that dioxin response elements (DREs are involved. These results are consistent with in vivo rat vs. mouse species-specific differential gene expression, and more comprehensive comparative DRE searches. Conclusions Comparative analysis of human HepG2, mouse Hepa1c1c7 and rat H4IIE TCDD-elicited gene expression responses is consistent with in vivo rat-mouse comparative gene expression studies, and more comprehensive comparative DRE searches, suggesting that AhR-mediated gene expression is species-specific.

  10. Intracellular Bacteria in Protozoa

    Science.gov (United States)

    Görtz, Hans-Dieter; Brigge, Theo

    Intracellular bacteria in humans are typically detrimental, and such infections are regarded by the patients as accidental and abnormal. In protozoa it seems obvious that many bacteria have coevolved with their hosts and are well adapted to the intracellular way of life. Manifold interactions between hosts and intracellular bacteria are found, and examples of antibacterial resistance of unknown mechanisms are observed. The wide diversity of intracellular bacteria in protozoa has become particularly obvious since they have begun to be classified by molecular techniques. Some of the bacteria are closely related to pathogens; others are responsible for the production of toxins.

  11. Influence of natural substrates and co-occurring marine bacteria on the production of secondary metabolites by Photobacterium halotolerans

    DEFF Research Database (Denmark)

    Månsson, Maria; Giobergia, Sonia; Møller, Kirsten A.;

    Genome sequences reveal that our current standard laboratory conditions only support a fraction of the potential secondary metabolism in bacteria. Thus, we must rethink cultivation, detection, and isolation strategies for bacterial secondary metabolites in order to explore the huge, so far unchar...... uncharacterized chemical potential of these organisms. We are currently investigating the use of natural substrates and co-cultures with commensal bacteria to elicit or alter production of antibacterial compounds in marine bacteria....

  12. Quantum Field Theory without Divergences: Quantum Spacetime

    OpenAIRE

    Gadiyar, G. H.

    1994-01-01

    A fundamental length is introduced into physics in a way which respects the principles of relativity and quantum field theory. This improves the properties of quantum field theory: divergences are removed. How to quantize gravity is also indicated. When the fundamental length tends to zero the present version of quantum field theory is recovered.

  13. Taming infrared divergences in the effective potential

    Energy Technology Data Exchange (ETDEWEB)

    Elias-Miro, J. [IFAE, Univ. Autonoma de Barcelona (Spain); Universitat Autonoma de Barcelona (Spain). Dept. de Fisica; Espinosa, J.R. [IFAE, Univ. Autonoma de Barcelona (Spain); ICREA, Institucio Catalana de Recerca i Estudis Avancats, Barcelona (Spain); Konstandin, T. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2014-06-15

    The Higgs effective potential in the Standard Model (SM), calculated perturbatively, generically suffers from infrared (IR) divergences when the (field-dependent) tree-level mass of the Goldstone bosons goes to zero. Such divergences can affect both the potential and its first derivative and become worse with increasing loop order. In this paper we show that these IR divergences are spurious, we perform a simple resummation of all IR-problematic terms known (up to three loops) and explain how to extend the resummation to cure all such divergences to any order. The method is of general applicability and would work in scenarios other than the SM. Our discussion has some bearing on a scenario recently proposed as a mechanism for gauge mediation of scale breaking in the ultraviolet, in which it is claimed that the low-energy Higgs potential is non-standard. We argue that all non-decoupling effects from the heavy sector can be absorbed in the renormalization of low-energy parameters leading to a SM-like effective theory.

  14. Coxiella burnetii and Leishmania mexicana residing within similar parasitophorous vacuoles elicit disparate host responses

    Directory of Open Access Journals (Sweden)

    Jess A Millar

    2015-08-01

    Full Text Available Coxiella burnetii is a bacterium that thrives in an acidic parasitophorous vacuole (PV derived from lysosomes. Leishmania mexicana, a eukaryote, has also independently evolved to live in a morphologically similar PV. As Coxiella and Leishmania are highly divergent organisms that cause different diseases, we reasoned that their respective infections would likely elicit distinct host responses despite producing phenotypically similar parasite-containing vacuoles. The objective of this study was to investigate, at the molecular level, the macrophage response to each pathogen. Infection of THP-1 (human monocyte/macrophage cells with Coxiella and Leishmania elicited disparate host responses. At 5 days post-infection, when compared to uninfected cells, 1057 genes were differentially expressed (746 genes up- and 311 genes down-regulated in C. burnetii infected cells, whereas 698 genes (534 genes up- and 164 genes down-regulated were differentially expressed in L. mexicana infected cells. Interestingly, of the 1755 differentially expressed genes identified in this study, only 126 genes (~7% are common to both infections. We also discovered that 1090 genes produced mRNA isoforms at significantly different levels under the two infection conditions, suggesting that alternate proteins encoded by the same gene might have important roles in host response to each infection. Additionally, we detected 257 micro RNAs (miRNAs that were expressed in THP-1 cells and identified miRNAs that were specifically expressed during Coxiella or Leishmania infections. Collectively, this study identified host mRNAs and miRNAs that were influenced by Coxiella and/or Leishmania infections. Intriguingly, our data indicate that although their PVs are morphologically similar, Coxiella and Leishmania have evolved different strategies that perturb distinct host processes to create and thrive within their respective intracellular niches.

  15. Expert elicitation on the uncertainties associated with chronic wasting disease.

    Science.gov (United States)

    Tyshenko, Michael G; Oraby, Tamer; Darshan, Shalu; Westphal, Margit; Croteau, Maxine C; Aspinall, Willy; Elsaadany, Susie; Krewski, Daniel; Cashman, Neil

    2016-01-01

    A high degree of uncertainty exists for chronic wasting disease (CWD) transmission factors in farmed and wild cervids. Evaluating the factors is important as it helps to inform future risk management strategies. Expert opinion is often used to assist decision making in a number of health, science, and technology domains where data may be sparse or missing. Using the "Classical Model" of elicitation, a group of experts was asked to estimate the most likely values for several risk factors affecting CWD transmission. The formalized expert elicitation helped structure the issues and hence provide a rational basis for estimating some transmission risk factors for which evidence is lacking. Considered judgments regarding environmental transmission, latency of CWD transmission, management, and species barrier were provided by the experts. Uncertainties for many items were determined to be large, highlighting areas requiring more research. The elicited values may be used as surrogate values until research evidence becomes available. PMID:27556566

  16. Expert elicitation on the uncertainties associated with chronic wasting disease.

    Science.gov (United States)

    Tyshenko, Michael G; Oraby, Tamer; Darshan, Shalu; Westphal, Margit; Croteau, Maxine C; Aspinall, Willy; Elsaadany, Susie; Krewski, Daniel; Cashman, Neil

    2016-01-01

    A high degree of uncertainty exists for chronic wasting disease (CWD) transmission factors in farmed and wild cervids. Evaluating the factors is important as it helps to inform future risk management strategies. Expert opinion is often used to assist decision making in a number of health, science, and technology domains where data may be sparse or missing. Using the "Classical Model" of elicitation, a group of experts was asked to estimate the most likely values for several risk factors affecting CWD transmission. The formalized expert elicitation helped structure the issues and hence provide a rational basis for estimating some transmission risk factors for which evidence is lacking. Considered judgments regarding environmental transmission, latency of CWD transmission, management, and species barrier were provided by the experts. Uncertainties for many items were determined to be large, highlighting areas requiring more research. The elicited values may be used as surrogate values until research evidence becomes available.

  17. A Novel Lactic Acid Bacteria Growth-stimulating Peptide from Broad Bean (Vicia faba .) Protein Hydrolysates

    OpenAIRE

    Ping Xiao; Yuan Liu; Rizwan-ur-Rehman; Ran Kang; Yanping Wang

    2015-01-01

    In this study, broad bean protein hydrolysates (BPH) produced by alcalase with strong-stimulating activity for lactic acid bacteria (LAB) was first time reported. In order to obtain the key peptide that have growth-stimulating activity for lactic acid bacteria (LAB), gel filtration chromatography and Reverse Phase High Performance Liquid Chromatography (RP-HPLC) were applied to isolate and purify the peptides from BPH. Finally, F4-2 elicited the highest activity for LAB, corresponding to amin...

  18. Genomics of Probiotic Bacteria

    Science.gov (United States)

    O'Flaherty, Sarah; Goh, Yong Jun; Klaenhammer, Todd R.

    Probiotic bacteria from the Lactobacillus and Bifidobacterium species belong to the Firmicutes and the Actinobacteria phylum, respectively. Lactobacilli are members of the lactic acid bacteria (LAB) group, a broadly defined family of microorganisms that ferment various hexoses into primarily lactic acid. Lactobacilli are typically low G + C gram-positive species which are phylogenetically diverse, with over 100 species documented to date. Bifidobacteria are heterofermentative, high G + C content bacteria with about 30 species of bifidobacteria described to date.

  19. Learning Chemistry from Bacteria

    OpenAIRE

    Clardy, Jon

    2013-01-01

    Dr. Jon Clardy Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Harvard University All animals, including humans, originated and evolved on a planet already teeming with bacteria, and the two kingdoms of life have been competing and cooperating through their joint history. Although bacteria are most familiar as pathogens, some bacteria produce small molecules that are essential for the biology of animals and other eukaryotes. This lecture explores some of...

  20. Structured Language Requirement Elicitation Using Case Base Reasoning

    Directory of Open Access Journals (Sweden)

    Marryam Murtaza

    2013-12-01

    Full Text Available Requirement elicitation is very difficult process in highly challenging and business based software as well as in real time software. Common problems associated with these types of software are rapidly changing the requirements and understanding the language of the layman person. In this study, a framework for requirement elicitation by using knowledge based system is proposed, which is very helpful for knowledge documentation, intelligent decision support, self-learning and more specifically it is very helpful for case based reasoning and explanation. Basically in this method requirements are gathered from Artificial Intelligence (AI expert system from various sources e.g., via interviews, scenarios or use cases. Then, these are converted into structured natural language using ontology and this new problem/case is put forward to Case Based Reasoning (CBR. CBR based on its previous information having similar requirements combines with new case and suggests a proposed solution. Based on this solution a prototype is developed and delivered to customer. The use of case-based reasoning in requirements elicitation process has greatly reduced the burden and saved time of requirement analyst and results in an effective solution for handling complex or vague requirements during the elicitation process.

  1. The Role of Elicited Verbal Imitation in Toddlers' Word Learning

    Science.gov (United States)

    Hodges, Rosemary; Munro, Natalie; Baker, Elise; McGregor, Karla; Docking, Kimberley; Arciuli, Joanne

    2016-01-01

    This study is about the role of elicited verbal imitation in toddler word learning. Forty-eight toddlers were taught eight nonwords linked to referents. During training, they were asked to imitate the nonwords. Naming of the referents was tested at three intervals (one minute later [uncued], five minutes, and 1-7 days later [cued]) and recognition…

  2. Teacher Burnout and Self-Efficacy in Eliciting Social Support.

    Science.gov (United States)

    Brouwers, Andre; Evers, Will J. G.; Tomic, Welko

    This study examined the relationship between perceived lack of social support, perceived self-efficacy in eliciting support at the workplace, and the three successive burnout symptoms (emotional exhaustion, depersonalization, and personal accomplishment) in a sample of 277 Dutch secondary school teachers. The study hypothesized that teachers'…

  3. Classifying groupware tools to improve communication in geographically distributed elicitation

    OpenAIRE

    Martín, Adriana; Martinez, Claudia; Martínez Carod, Nadina; Aranda, Gabriela N.; Cechich, Alejandra

    2003-01-01

    In a scene where stakeholders are geographically distributed, communication presents new challenges for research areas. Considering the characteristics of interpersonal communication and the virtual area where it is carried out, the importance of applying interdisciplinary approaches, such as Cognitive Engineering, is currently increasing. Particularly, our proposal aims at improving the interaction between stakeholders by applying learning models when eliciting distributed software requireme...

  4. Obstacle avoidance to elicit freezing of gait during treadmill walking.

    NARCIS (Netherlands)

    Snijders, A.H.; Weerdesteijn, V.G.M.; Hagen, Y.J.; Duysens, J.E.J.; Giladi, N.; Bloem, B.R.

    2010-01-01

    Freezing of gait (FOG) is a common and disabling feature of Parkinson's disease (PD). Detailed pathophysiological studies are hampered by the fact that FOG episodes are difficult to elicit in a gait laboratory. We evaluated whether the need to avoid sudden obstacles on a treadmill can provoke FOG. W

  5. Multisensory integration affects ERP components elicited by exogenous cues

    NARCIS (Netherlands)

    Santangelo, Valerio; Lubbe, van der Rob H.J.; Belardinelli, Marta Olivetti; Postma, Albert

    2008-01-01

    revious studies have shown that the amplitude of event related brain potentials (ERPs) elicited by a combined audiovisual stimulus is larger than the sum of a single auditory and visual stimulus. This enlargement is thought to reflect multisensory integration. Based on these data, it may be hypothes

  6. Creating a Framework: Art Therapy Elicits the Narrative

    Science.gov (United States)

    Harber, Karen

    2011-01-01

    A case study illustrates how art therapy was used to elicit the narrative of an adolescent male student in transition from incarceration to a transfer school setting. Childhood trauma was addressed in individual sessions and within a literacy group co-led by a reading specialist. The art therapist responded to the client's needs by broadening the…

  7. Conditioned craving cues elicit an automatic approach tendency

    NARCIS (Netherlands)

    D. van Gucht; D. Vansteenwegen; O. Van den Bergh; T. Beckers

    2008-01-01

    In two experiments, we used a Pavlovian differential conditioning procedure to induce craving for chocolate. As a result of repeated pairing with chocolate intake, initially neutral cues came to elicit an automatic approach tendency in a speeded stimulus-response compatibility reaction time task. Th

  8. Computational Support for Early Elicitation and Classification of Tone

    Science.gov (United States)

    Bird, Steven; Lee, Haejoong

    2014-01-01

    Investigating a tone language involves careful transcription of tone on words and phrases. This is challenging when the phonological categories--the tones or melodies--have not been identified. Effects such as coarticulation, sandhi, and phrase-level prosody appear as obstacles to early elicitation and classification of tone. This article presents…

  9. Expert Elicitation Method Selection Process and Method Comparison

    Energy Technology Data Exchange (ETDEWEB)

    Dalton, Angela C.; Brothers, Alan J.; Walsh, Stephen J.; Whitney, Paul D.

    2010-09-21

    Research on integrative modeling has gained considerable attention in recent years and expert opinion has been increasingly recognized as an important data source and modeling contributor. However, little research has systematically compared and evaluated expert elicitation methods in terms of their ability to link to computational models that capture human behavior and social phenomena. In this paper, we describe a decision-making process we used for evaluating and selecting a task specific elicitation method within the framework of integrative computational social-behavioral modeling. From the existing literature, we identified the characteristics of problems that each candidate method is well suited to address. A small-scale expert elicitation was also conducted to evaluate the comparative strength and weaknesses of the methods against a number of consensus-based decision criteria. By developing a set of explicit method evaluation criteria and a description characterizing decision problems for the candidate methods, we seek to gain a better understanding of the feasibility and cost-effectiveness of integrating elicitation methods with computational modeling techniques. This serves an important first step toward expanding our research effort and trajectory toward greater interdisciplinary modeling research of human behavior.

  10. A Task that Elicits Reasoning: A Dual Analysis

    Science.gov (United States)

    Yankelewitz, Dina; Mueller, Mary; Maher, Carolyn A.

    2010-01-01

    This paper reports on the forms of reasoning elicited as fourth grade students in a suburban district and sixth grade students in an urban district worked on similar tasks involving reasoning with the use of Cuisenaire rods. Analysis of the two data sets shows similarities in the reasoning used by both groups of students on specific tasks, and the…

  11. Adaptive Mixture Methods Based on Bregman Divergences

    CERN Document Server

    Donmez, Mehmet A; Kozat, Suleyman S

    2012-01-01

    We investigate adaptive mixture methods that linearly combine outputs of $m$ constituent filters running in parallel to model a desired signal. We use "Bregman divergences" and obtain certain multiplicative updates to train the linear combination weights under an affine constraint or without any constraints. We use unnormalized relative entropy and relative entropy to define two different Bregman divergences that produce an unnormalized exponentiated gradient update and a normalized exponentiated gradient update on the mixture weights, respectively. We then carry out the mean and the mean-square transient analysis of these adaptive algorithms when they are used to combine outputs of $m$ constituent filters. We illustrate the accuracy of our results and demonstrate the effectiveness of these updates for sparse mixture systems.

  12. Enhancing Divergent Search through Extinction Events

    DEFF Research Database (Denmark)

    Lehman, Joel; Miikkulainen, Risto

    2015-01-01

    A challenge in evolutionary computation is to create representations as evolvable as those in natural evolution. This paper hypothesizes that extinction events, i.e. mass extinctions, can significantly increase evolvability, but only when combined with a divergent search algorithm, i.e. a search...... driven towards diversity (instead of optimality). Extinctions amplify diversity-generation by creating unpredictable evolutionary bottlenecks. Persisting through multiple such bottlenecks is more likely for lineages that diversify across many niches, resulting in indirect selection pressure...... for the capacity to evolve. This hypothesis is tested through experiments in two evolutionary robotics domains. The results show that combining extinction events with divergent search increases evolvability, while combining them with convergent search offers no similar benefit. The conclusion is that extinction...

  13. Multiple Source Adaptation and the Renyi Divergence

    CERN Document Server

    Mansour, Yishay; Rostamizadeh, Afshin

    2012-01-01

    This paper presents a novel theoretical study of the general problem of multiple source adaptation using the notion of Renyi divergence. Our results build on our previous work [12], but significantly broaden the scope of that work in several directions. We extend previous multiple source loss guarantees based on distribution weighted combinations to arbitrary target distributions P, not necessarily mixtures of the source distributions, analyze both known and unknown target distribution cases, and prove a lower bound. We further extend our bounds to deal with the case where the learner receives an approximate distribution for each source instead of the exact one, and show that similar loss guarantees can be achieved depending on the divergence between the approximate and true distributions. We also analyze the case where the labeling functions of the source domains are somewhat different. Finally, we report the results of experiments with both an artificial data set and a sentiment analysis task, showing the p...

  14. Higgsed Stueckelberg vector and Higgs quadratic divergence

    Directory of Open Access Journals (Sweden)

    Durmuş Ali Demir

    2015-01-01

    Full Text Available Here we show that, a hidden vector field whose gauge invariance is ensured by a Stueckelberg scalar and whose mass is spontaneously generated by the Standard Model Higgs field contributes to quadratic divergences in the Higgs boson mass squared, and even leads to its cancellation at one-loop when Higgs coupling to gauge field is fine-tuned. In contrast to mechanisms based on hidden scalars where a complete cancellation cannot be achieved, stabilization here is complete in that the hidden vector and the accompanying Stueckelberg scalar are both free from quadratic divergences at one-loop. This stability, deriving from hidden exact gauge invariance, can have important implications for modeling dark phenomena like dark matter, dark energy, dark photon and neutrino masses. The hidden fields can be produced at the LHC.

  15. Flow over convergent and divergent wall riblets

    Energy Technology Data Exchange (ETDEWEB)

    Koeltzsch, K.; Dinkelacker, A.; Grundmann, R. [Institut fuer Luft- und Raumfahrttechnik, Technische Universitaet Dresden, 36460 Merkers (Germany)

    2002-08-01

    Fast swimming sharks have small riblets on their skin, which are assumed to improve the swimming performance of the fish. Fluid dynamic experiments in water as well as in air confirm this assumption. With riblet surfaces as compared to smooth surfaces, drag reductions up to about 10% were measured. The overall riblet pattern on sharks shows parallel riblets directed from head to tail, but besides this overall pattern fast swimming sharks have also small areas with converging riblets and others with diverging riblets. In the present study the velocity field over convergent and divergent riblet patterns is investigated by hot-wire measurements in turbulent pipe flow. Significant changes in the near wall velocity field were found. (orig.)

  16. Nucleosomes shape DNA polymorphism and divergence.

    Directory of Open Access Journals (Sweden)

    Sasha A Langley

    2014-07-01

    Full Text Available An estimated 80% of genomic DNA in eukaryotes is packaged as nucleosomes, which, together with the remaining interstitial linker regions, generate higher order chromatin structures [1]. Nucleosome sequences isolated from diverse organisms exhibit ∼10 bp periodic variations in AA, TT and GC dinucleotide frequencies. These sequence elements generate intrinsically curved DNA and help establish the histone-DNA interface. We investigated an important unanswered question concerning the interplay between chromatin organization and genome evolution: do the DNA sequence preferences inherent to the highly conserved histone core exert detectable natural selection on genomic divergence and polymorphism? To address this hypothesis, we isolated nucleosomal DNA sequences from Drosophila melanogaster embryos and examined the underlying genomic variation within and between species. We found that divergence along the D. melanogaster lineage is periodic across nucleosome regions with base changes following preferred nucleotides, providing new evidence for systematic evolutionary forces in the generation and maintenance of nucleosome-associated dinucleotide periodicities. Further, Single Nucleotide Polymorphism (SNP frequency spectra show striking periodicities across nucleosomal regions, paralleling divergence patterns. Preferred alleles occur at higher frequencies in natural populations, consistent with a central role for natural selection. These patterns are stronger for nucleosomes in introns than in intergenic regions, suggesting selection is stronger in transcribed regions where nucleosomes undergo more displacement, remodeling and functional modification. In addition, we observe a large-scale (∼180 bp periodic enrichment of AA/TT dinucleotides associated with nucleosome occupancy, while GC dinucleotide frequency peaks in linker regions. Divergence and polymorphism data also support a role for natural selection in the generation and maintenance of these

  17. Automated leukocyte recognition using fuzzy divergence.

    Science.gov (United States)

    Ghosh, Madhumala; Das, Devkumar; Chakraborty, Chandan; Ray, Ajoy K

    2010-10-01

    This paper aims at introducing an automated approach to leukocyte recognition using fuzzy divergence and modified thresholding techniques. The recognition is done through the segmentation of nuclei where Gamma, Gaussian and Cauchy type of fuzzy membership functions are studied for the image pixels. It is in fact found that Cauchy leads better segmentation as compared to others. In addition, image thresholding is modified for better recognition. Results are studied and discussed.

  18. COMPARATIVE FINANCIAL STATEMENTS. CONVERGENCE VERSUS DIVERGENCE

    Directory of Open Access Journals (Sweden)

    Nicolae ECOBICI

    2010-09-01

    Full Text Available In this paper I compared the Romanian financial statements with the US GAAP financial statements in terms of two criteria: first the reference period and secondly the shape, structure and content of financial statements. Nowadays the two accounting systems, the French and Anglo-Saxon, tend to harmonize. I will present the convergences and the divergences between the financial statements of Romania, subject to OMFP 3055/2009, in parallel with the Anglo-Saxon accounting system.

  19. Generalized divergence measures for survival and reliability data

    Science.gov (United States)

    Vonta, Ilia; Karagrigoriou, Alex

    2012-11-01

    Measures of divergence or discrepancy are used either to measure mutual information concerning two variables or to construct model selection criteria. In this paper we are focusing on divergence measures that are based on a class of measures known as Csiszar's divergence measures. We focus on some generalizations of measures of divergence and propose a class of goodness of fit tests based on Csiszar's class of measures designed for censored survival or reliability data.

  20. On the Benefits of Divergent Search for Evolved Representations

    DEFF Research Database (Denmark)

    Lehman, Joel; Risi, Sebastian; Stanley, Kenneth O

    2012-01-01

    explicit objectives that are consequently divergent may implicitly reward lineages that continually diverge, thereby indirectly selecting for evolvable representations that are better able to diverge further. This paper reviews a range of past results that support such a hypothesis from a method called...... novelty search, which explicitly rewards novelty, i.e. behaviors that diverge from previously encountered behaviors. In many experiments, novelty search demonstrates significant representational advantages over traditional fitness-based search, such as evolving more compact solutions, uncovering more...

  1. How honey kills bacteria

    NARCIS (Netherlands)

    P.H.S. Kwakman; A.A. te Velde; L. de Boer; D. Speijer; C.M.J.E. Vandenbroucke-Grauls; S.A.J. Zaat

    2010-01-01

    With the rise in prevalence of antibiotic-resistant bacteria, honey is increasingly valued for its antibacterial activity. To characterize all bactericidal factors in a medical-grade honey, we used a novel approach of successive neutralization of individual honey bactericidal factors. All bacteria t

  2. Metallization of bacteria cells

    Institute of Scientific and Technical Information of China (English)

    LI; Xiangfeng; (黎向锋); LI; Yaqin; (李雅芹); CAI; Jun; (蔡军); ZHANG; Deyuan; (张德远)

    2003-01-01

    Bacteria cells with different standard shapes are well suited for use as templates for the fabrication of magnetic and electrically conductive microstructures. In this paper, metallization of bacteria cells is demonstrated by an electroless deposition technique of nickel-phosphorus initiated by colloid palladium-tin catalyst on the surfaces of Citeromyces matritensis and Bacillus cereus. The activated and metallized bacteria cells have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction analysis (XRD). Results showed that both Citeromyces matritensis and Bacillus cereus had no deformation in shape after metallization; the metallized films deposited on the surfaces of bacteria cells are homogeneous in thickness and noncrystalline in phase structure. The kinetics of colloid palladium-tin solution and electroless plating on bacteria cells is discussed.

  3. Edge Extraction with an Anisotropic Vector Field using Divergence Map

    Directory of Open Access Journals (Sweden)

    Giuliani Donatella

    2012-08-01

    Full Text Available The aim of this work is the extraction of edges by a deformable contour procedure, using an external force field derived from an anisotropic flow, with different external and initial conditions. By evaluating the divergence of the force field, we have generated a divergence map associated with it in order to analyze the field convergence. As we know, the divergence measures the intensity of convergence or divergence of a vector field at a given point, so by means level curves of the divergence map, we have automatically selected an initial contour for the deformation process. The initial curve must include areas from which the vector field diverges pushing it towards the edges. Furthermore the divergence map brings out the presence of curves pointing to the most significant geometric parts of boundaries corresponding to high curvature values, in this way it will result better defined the geometrical shape of the extracted object.

  4. Expert elicitation for a national-level volcano hazard model

    Science.gov (United States)

    Bebbington, Mark; Stirling, Mark; Cronin, Shane; Wang, Ting; Jolly, Gill

    2016-04-01

    The quantification of volcanic hazard at national level is a vital pre-requisite to placing volcanic risk on a platform that permits meaningful comparison with other hazards such as earthquakes. New Zealand has up to a dozen dangerous volcanoes, with the usual mixed degrees of knowledge concerning their temporal and spatial eruptive history. Information on the 'size' of the eruptions, be it in terms of VEI, volume or duration, is sketchy at best. These limitations and the need for a uniform approach lend themselves to a subjective hazard analysis via expert elicitation. Approximately 20 New Zealand volcanologists provided estimates for the size of the next eruption from each volcano and, conditional on this, its location, timing and duration. Opinions were likewise elicited from a control group of statisticians, seismologists and (geo)chemists, all of whom had at least heard the term 'volcano'. The opinions were combined via the Cooke classical method. We will report on the preliminary results from the exercise.

  5. Between participants, props and stage: Eliciting insights through interaction

    DEFF Research Database (Denmark)

    Cramer-Petersen, Claus Lundgaard; Marijnissen, Thomas

    2012-01-01

    How can we develop innovative concepts? The purpose of this paper is to investigate how generative prototype sessions can elicit so-called tacit and latent knowledge from participants through interaction and play. To illustrate this, a session from the design process will be described along with ...... an indiscernible blend of different types of knowledge, but that tacit and latent constitutes an important part.......How can we develop innovative concepts? The purpose of this paper is to investigate how generative prototype sessions can elicit so-called tacit and latent knowledge from participants through interaction and play. To illustrate this, a session from the design process will be described along with a...... brief take on current theories. It is discussed how practical tools and methods along with the dynamics occurring during such a session can translate actor knowledge to become useful throughout a the entire design process. The paper concludes that knowledge gained from generative prototype sessions is...

  6. Arousal recognition system based on heartbeat dynamics during auditory elicitation.

    Science.gov (United States)

    Nardelli, Mimma; Valenza, Gaetano; Greco, Alberto; Lanata, Antonio; Scilingo, Enzo Pasquale

    2015-08-01

    This study reports on the recognition of different arousal levels, elicited by affective sounds, performed using estimates of autonomic nervous system dynamics. Specifically, as a part of the circumplex model of affect, arousal levels were recognized by properly combining information gathered from standard and nonlinear analysis of heartbeat dynamics, which was derived from the electrocardiogram (ECG). Affective sounds were gathered from the International Affective Digitized Sound System and grouped into four different levels of arousal. A group of 27 healthy volunteers underwent such elicitation while ECG signals were continuously recorded. Results showed that a quadratic discriminant classifier, as applied implementing a leave-one-subject-out procedure, achieved a recognition accuracy of 84.26%. Moreover, this study confirms the crucial role of heartbeat nonlinear dynamics for emotion recognition, hereby estimated through lagged Poincare plots. PMID:26737686

  7. Gene duplication and divergence produce divergent MHC genotypes without disassortative mating.

    Science.gov (United States)

    Dearborn, Donald C; Gager, Andrea B; McArthur, Andrew G; Gilmour, Morgan E; Mandzhukova, Elena; Mauck, Robert A

    2016-09-01

    Genes of the major histocompatibility complex (MHC) exhibit heterozygote advantage in immune defence, which in turn can select for MHC-disassortative mate choice. However, many species lack this expected pattern of MHC-disassortative mating. A possible explanation lies in evolutionary processes following gene duplication: if two duplicated MHC genes become functionally diverged from each other, offspring will inherit diverse multilocus genotypes even under random mating. We used locus-specific primers for high-throughput sequencing of two expressed MHC Class II B genes in Leach's storm-petrels, Oceanodroma leucorhoa, and found that exon 2 alleles fall into two gene-specific monophyletic clades. We tested for disassortative vs. random mating at these two functionally diverged Class II B genes, using multiple metrics and different subsets of exon 2 sequence data. With good statistical power, we consistently found random assortment of mates at MHC. Despite random mating, birds had MHC genotypes with functionally diverged alleles, averaging 13 amino acid differences in pairwise comparisons of exon 2 alleles within individuals. To test whether this high MHC diversity in individuals is driven by evolutionary divergence of the two duplicated genes, we built a phylogenetic permutation model. The model showed that genotypic diversity was strongly impacted by sequence divergence between the most common allele of each gene, with a smaller additional impact of monophyly of the two genes. Divergence of allele sequences between genes may have reduced the benefits of actively seeking MHC-dissimilar mates, in which case the evolutionary history of duplicated genes is shaping the adaptive landscape of sexual selection. PMID:27376487

  8. Manipulation and stretching of bacteria and liposomes by Microfluidics

    Science.gov (United States)

    Zussman, Eyal; Salalha, Wael

    2006-03-01

    Microfluidic technology can be useful in lab-on-a-chip applications of biological assays, environmental monitoring, detection of toxic materials, as well as for assembly of nano- and micro-scale objects into more complex systems. In this work we focused on the orientation of rod-shaped bacteria (Bacillus) by employing shear flow and a high rate elongation flow, and stretching of giant liposomes with diameter size of tens of microns, which can be used as a simplified model for cell behavior. This was achieved by flows of dilute rod-like bacteria and liposome suspensions within a micro-channel by means of a capillary-driven motion. Fluidic alignment situations were tested, firstly by Venturi-like flow which produces a sufficiently converging and diverging flow, and secondly by sink-like flow in a converging microchannel. In the first method we found that the converging part of the flow aligns rod-like bacteria, whereas the diverging part disaligns them, while in the second method the rod-like bacteria can perfectly align along the streamlines. In addition we used the same technology to test liposome deformation while they are flowing through a Venturi-like microchannel. The microfluidics devices were fabricated from poly(dimethylsiloxane) (PDMS) by soft lithographic techniques.

  9. Multiple Membrane Interactions and Versatile Vesicle Deformations Elicited by Melittin

    OpenAIRE

    Kingo Takiguchi; Michio Homma; Yasunori Yokoyama; Yohko Tanaka-Takiguchi; Tomoyoshi Takahashi; Fumimasa Nomura

    2013-01-01

    Melittin induces various reactions in membranes and has been widely studied as a model for membrane-interacting peptide; however, the mechanism whereby melittin elicits its effects remains unclear. Here, we observed melittin-induced changes in individual giant liposomes using direct real-time imaging by dark-field optical microscopy, and the mechanisms involved were correlated with results obtained using circular dichroism, cosedimentation, fluorescence quenching of tryptophan residues, and e...

  10. UML for Early Requirements Elicitation: A Regulation based Approach

    OpenAIRE

    Regev, Gil; Wegmann, Alain

    2002-01-01

    Early requirements of information systems are often understood in terms of the elicitation of stakeholders' high-level goals to be supported by the system under discussion. Stakeholders' goals are considered as the ultimate explanation of requirements. It is assumed that the notion of a high-level goal is natural and that high-level goals need no explanation with regard to their origins. We believe that these assumptions result in the definition of inadequate goals. We propose an organization...

  11. Neutrosophic Logic for Mental Model Elicitation and Analysis

    Directory of Open Access Journals (Sweden)

    Karina Pérez-Teruel

    2014-03-01

    Full Text Available Mental models are personal, internal representations of external reality that people use to interact with the world around them. They are useful in multiple situations such as muticriteria decision making, knowledge management, complex system learning and analysis. In this paper a framework for mental models elicitation and analysis based on neutrosophic Logic is presented. An illustrative example is provided to show the applicability of the proposal. The paper ends with conclusion future research directions.

  12. Classical vs. crowdsourcing surveys for eliciting geographic relevance criteria

    OpenAIRE

    De Sabbata, Stefano; Alonso, Omar; Mizzaro, Stefano

    2012-01-01

    Geographic relevance aims to assess the relevance of physical entities (e.g., shops and museums) in geographic space for a mobile user in a given context, thereby shifting the focus from the digital world (the realm of classical information retrieval) to the physical world. We study the elicitation of geographic relevance criteria by means of both a classical survey and an Amazon Mechanical Turk (a crowdsourcing platform) survey. This allows us to obtain three results: first, we gather a set ...

  13. The Elicitation of Subjective Probabilities with Applications in Agricultural Economics

    OpenAIRE

    Patricia E. NORRIS; Randall A. Kramer

    1990-01-01

    Probability judgements are important components of decision making under uncertainty. In particular, economic decisions can be aided by assuring more accurate assessment of probabilities and more realistic modelling of economic problems through the inclusion of subjective probabilities. The purpose of this paper is to describe the techniques which can be used to elicit subjective probabilities and the ways in which these techniques can be incorporated into agricultural economics research. The...

  14. Gender difference in N170 elicited under oddball task

    OpenAIRE

    Choi, Damee; Egashira, Yuka; Takakura, Jun’ya; Motoi, Midori; Nishimura, Takayuki; Watanuki, Shigeki

    2015-01-01

    Background: Some studies have reported gender differences in N170, a face-selective event-related potential (ERP) component. This study investigated gender differences in N170 elicited under oddball paradigm in order to clarify the effect of task demand on gender differences in early facial processing. Findings: Twelve males and 10 females discriminated targets (emotional faces) from non-targets (emotionally neutral faces) under an oddball paradigm, pressing a button as quickly as possible in...

  15. Gender difference in N170 elicited under oddball task

    OpenAIRE

    Choi, Damee; Egashira, Yuka; Takakura, Jun’ya; Motoi, Midori; Nishimura, Takayuki; Watanuki, Shigeki

    2015-01-01

    Background Some studies have reported gender differences in N170, a face-selective event-related potential (ERP) component. This study investigated gender differences in N170 elicited under oddball paradigm in order to clarify the effect of task demand on gender differences in early facial processing. Findings Twelve males and 10 females discriminated targets (emotional faces) from non-targets (emotionally neutral faces) under an oddball paradigm, pressing a button as quickly as possible in r...

  16. Some Divergence Properties of Asset Price Models

    Science.gov (United States)

    Stummer, Wolfgang

    2001-12-01

    We consider asset price processes Xt which are weak solutions of one-dimensional stochastic differential equations of the form (equation (2)) Such price models can be interpreted as non-lognormally-distributed generalizations of the geometric Brownian motion. We study properties of the Iα-divergence between the law of the solution Xt and the corresponding drift-less measure (the special case α=1 is the relative entropy). This will be applied to some context in statistical information theory as well as to arbitrage theory and contingent claim valuation. For instance, the seminal option pricing theorems of Black-Scholes and Merton appear as a special case.

  17. Probabilistic divergence measures for detecting interspecies recombination.

    Science.gov (United States)

    Husmeier, D; Wright, F

    2001-01-01

    This paper proposes a graphical method for detecting interspecies recombination in multiple alignments of DNA sequences. A fixed-size window is moved along a given DNA sequence alignment. For every position, the marginal posterior probability over tree topologies is determined by means of a Markov chain Monte Carlo simulation. Two probabilistic divergence measures are plotted along the alignment, and are used to identify recombinant regions. The method is compared with established detection methods on a set of synthetic benchmark sequences and two real-world DNA sequence alignments.

  18. The Eurozone Dynamic Cohesion: Convergence or Divergence

    Directory of Open Access Journals (Sweden)

    Antonin Rusek

    2013-08-01

    Full Text Available The long term economic dynamics of the Eurozone’s original 12 countries (Greece, Italy, Spain, Portugal, Ireland, Germany, Netherlands, Luxembourg, Belgium, Austria, Finland, France is analyzed and compared. It is today increasingly recognized that the diverging competitiveness between the Eurozone members is at the root of the current crisis. But the competitiveness dynamics and its impact on the crucial fiscal and financial variables during the common currency existence is seldom analyzed and compared, especially as far as the different groups of countries (and/or different areas within the Eurozone are concerned.

  19. Projection Pursuit Through ϕ-Divergence Minimisation

    Directory of Open Access Journals (Sweden)

    Jacques Touboul

    2010-06-01

    Full Text Available In his 1985 article (“Projection pursuit”, Huber demonstrates the interest of his method to estimate a density from a data set in a simple given case. He considers the factorization of density through a Gaussian component and some residual density. Huber’s work is based on maximizing Kullback–Leibler divergence. Our proposal leads to a new algorithm. Furthermore, we will also consider the case when the density to be factorized is estimated from an i.i.d. sample. We will then propose a test for the factorization of the estimated density. Applications include a new test of fit pertaining to the elliptical copulas.

  20. More on divergences in brane world models

    CERN Document Server

    Smolyakov, Mikhail N

    2013-01-01

    In this note a model in a space-time with compact extra dimension, describing five-dimensional fermion fields interacting with electromagnetic field localized on a brane, is presented. This model can be considered as a toy model for examining possible consequences of localization of gauge fields on a brane. It is shown that in the limit of infinite extra dimension the lowest order amplitudes of some processes in the resulting four-dimensional effective theory are divergent. Such a "localization catastrophe" can be inherent to more realistic bane world models with infinite extra dimension.

  1. Comparative genomics of Thermus thermophilus and Deinococcus radiodurans: divergent routes of adaptation to thermophily and radiation resistance

    Directory of Open Access Journals (Sweden)

    Daly Michael J

    2005-10-01

    Full Text Available Abstract Background Thermus thermophilus and Deinococcus radiodurans belong to a distinct bacterial clade but have remarkably different phenotypes. T. thermophilus is a thermophile, which is relatively sensitive to ionizing radiation and desiccation, whereas D. radiodurans is a mesophile, which is highly radiation- and desiccation-resistant. Here we present an in-depth comparison of the genomes of these two related but differently adapted bacteria. Results By reconstructing the evolution of Thermus and Deinococcus after the divergence from their common ancestor, we demonstrate a high level of post-divergence gene flux in both lineages. Various aspects of the adaptation to high temperature in Thermus can be attributed to horizontal gene transfer from archaea and thermophilic bacteria; many of the horizontally transferred genes are located on the single megaplasmid of Thermus. In addition, the Thermus lineage has lost a set of genes that are still present in Deinococcus and many other mesophilic bacteria but are not common among thermophiles. By contrast, Deinococcus seems to have acquired numerous genes related to stress response systems from various bacteria. A comparison of the distribution of orthologous genes among the four partitions of the Deinococcus genome and the two partitions of the Thermus genome reveals homology between the Thermus megaplasmid (pTT27 and Deinococcus megaplasmid (DR177. Conclusion After the radiation from their common ancestor, the Thermus and Deinococcus lineages have taken divergent paths toward their distinct lifestyles. In addition to extensive gene loss, Thermus seems to have acquired numerous genes from thermophiles, which likely was the decisive contribution to its thermophilic adaptation. By contrast, Deinococcus lost few genes but seems to have acquired many bacterial genes that apparently enhanced its ability to survive different kinds of environmental stresses. Notwithstanding the accumulation of

  2. Tamoxifen-elicited uterotrophy: cross-species and cross-ligand analysis of the gene expression program

    Directory of Open Access Journals (Sweden)

    Forgacs Agnes L

    2009-04-01

    Full Text Available Abstract Background Tamoxifen (TAM is a well characterized breast cancer drug and selective estrogen receptor modulator (SERM which also has been associated with a small increase in risk for uterine cancers. TAM's partial agonist activation of estrogen receptor has been characterized for specific gene promoters but not at the genomic level in vivo.Furthermore, reducing uncertainties associated with cross-species extrapolations of pharmaco- and toxicogenomic data remains a formidable challenge. Results A comparative ligand and species analysis approach was conducted to systematically assess the physiological, morphological and uterine gene expression alterations elicited across time by TAM and ethynylestradiol (EE in immature ovariectomized Sprague-Dawley rats and C57BL/6 mice. Differential gene expression was evaluated using custom cDNA microarrays, and the data was compared to identify conserved and divergent responses. 902 genes were differentially regulated in all four studies, 398 of which exhibit identical temporal expression patterns. Conclusion Comparative analysis of EE and TAM differentially expressed gene lists suggest TAM regulates no unique uterine genes that are conserved in the rat and mouse. This demonstrates that the partial agonist activities of TAM extend to molecular targets in regulating only a subset of EE-responsive genes. Ligand-conserved, species-divergent expression of carbonic anhydrase 2 was observed in the microarray data and confirmed by real time PCR. The identification of comparable temporal phenotypic responses linked to related gene expression profiles demonstrates that systematic comparative genomic assessments can elucidate important conserved and divergent mechanisms in rodent estrogen signalling during uterine proliferation.

  3. Extracellular communication in bacteria

    DEFF Research Database (Denmark)

    Chhabra, S.R.; Philipp, B.; Eberl, L.;

    2005-01-01

    molecules, in different Gram-positive and Gram-negative bacteria they control pathogenicity, secondary metabolite production, biofilm differentiation, DNA transfer and bioluminescence. The development of biosensors for the detection of these signal molecules has greatly facilitated their subsequent chemical...

  4. Indicator For Pseudomonas Bacteria

    Science.gov (United States)

    Margalit, Ruth

    1990-01-01

    Characteristic protein extracted and detected. Natural protein marker found in Pseudomonas bacteria. Azurin, protein containing copper readily extracted, purified, and used to prepare antibodies. Possible to develop simple, fast, and accurate test for marker carried out in doctor's office.

  5. World health inequality: convergence, divergence, and development.

    Science.gov (United States)

    Clark, Rob

    2011-02-01

    Recent studies characterize the last half of the twentieth century as an era of cross-national health convergence, with some attributing welfare gains in the developing world to economic growth. In this study, I examine the extent to which welfare outcomes have actually converged and the extent to which economic development is responsible for the observed trends. Drawing from estimates covering 195 nations during the 1955-2005 period, I find that life expectancy averages converged during this time, but that infant mortality rates continuously diverged. I develop a narrative that implicates economic development in these contrasting trends, suggesting that health outcomes follow a "welfare Kuznets curve." Among poor countries, economic development improves life expectancy more than it reduces infant mortality, whereas the situation is reversed among wealthier nations. In this way, development has contributed to both convergence in life expectancy and divergence in infant mortality. Drawing from 674 observations across 163 countries during the 1980-2005 period, I find that the positive effect of GDP PC on life expectancy attenuates at higher levels of development, while the negative effect of GDP PC on infant mortality grows stronger.

  6. The future costs of nuclear power using multiple expert elicitations: effects of RD&D and elicitation design

    Science.gov (United States)

    Díaz Anadón, Laura; Nemet, Gregory; Verdolini, Elena

    2013-09-01

    Characterization of the anticipated performance of energy technologies to inform policy decisions increasingly relies on expert elicitation. Knowledge about how elicitation design factors impact the probabilistic estimates emerging from these studies is, however, scarce. We focus on nuclear power, a large-scale low-carbon power option, for which future cost estimates are important for the design of energy policies and climate change mitigation efforts. We use data from three elicitations in the USA and in Europe and assess the role of government research, development, and demonstration (RD&D) investments on expected nuclear costs in 2030. We show that controlling for expert, technology, and design characteristics increases experts’ implied public RD&D elasticity of expected costs by 25%. Public sector and industry experts’ cost expectations are 14% and 32% higher, respectively than academics. US experts are more optimistic than their EU counterparts, with median expected costs 22% lower. On average, a doubling of public RD&D is expected to result in an 8% cost reduction, but the uncertainty is large. The difference between the 90th and 10th percentile estimates is on average 58% of the experts’ median estimates. Public RD&D investments do not affect uncertainty ranges, but US experts are less confident about costs than Europeans.

  7. The future costs of nuclear power using multiple expert elicitations: effects of RD and D and elicitation design

    International Nuclear Information System (INIS)

    Characterization of the anticipated performance of energy technologies to inform policy decisions increasingly relies on expert elicitation. Knowledge about how elicitation design factors impact the probabilistic estimates emerging from these studies is, however, scarce. We focus on nuclear power, a large-scale low-carbon power option, for which future cost estimates are important for the design of energy policies and climate change mitigation efforts. We use data from three elicitations in the USA and in Europe and assess the role of government research, development, and demonstration (RD and D) investments on expected nuclear costs in 2030. We show that controlling for expert, technology, and design characteristics increases experts’ implied public RD and D elasticity of expected costs by 25%. Public sector and industry experts’ cost expectations are 14% and 32% higher, respectively than academics. US experts are more optimistic than their EU counterparts, with median expected costs 22% lower. On average, a doubling of public RD and D is expected to result in an 8% cost reduction, but the uncertainty is large. The difference between the 90th and 10th percentile estimates is on average 58% of the experts’ median estimates. Public RD and D investments do not affect uncertainty ranges, but US experts are less confident about costs than Europeans. (letter)

  8. Seven Means, Generalized Triangular Discrimination, and Generating Divergence Measures

    Directory of Open Access Journals (Sweden)

    Inder Jeet Taneja

    2013-04-01

    Full Text Available Jensen-Shannon, J-divergence and Arithmetic-Geometric mean divergences are three classical divergence measures known in the information theory and statistics literature. These three divergence measures bear interesting inequality among the three non-logarithmic measures known as triangular discrimination, Hellingar’s divergence and symmetric chi-square divergence. However, in 2003, Eve studied seven means from a geometrical point of view, which are Harmonic, Geometric, Arithmetic, Heronian, Contra-harmonic, Root-mean square and Centroidal. In this paper, we have obtained new inequalities among non-negative differences arising from these seven means. Correlations with generalized triangular discrimination and some new generating measures with their exponential representations are also presented.

  9. A Sequence of Inequalities among Difference of Symmetric Divergence Measures

    CERN Document Server

    Taneja, Inder Jeet

    2011-01-01

    In this paper we have considered two one parametric generalizations. These two generalizations have in articular the well known measures such as: J-divergence, Jensen-Shannon divergence and Arithmetic-Geometric mean divergence. These three measures are with logarithmic expressions. Also, we have particular cases the measures such as: Hellinger discrimination, symmetric chi-square divergence, and triangular discrimination. These three measures are also well-known in the literature of statistics, and are without logarithmic expressions. Still, we have one more non logarithmic measure as particular case calling it d-divergence. These seven measures bear an interesting inequality. Based on this inequality, we have considered different difference of divergence measures and established a sequence of inequalities among themselves.

  10. The fecal bacteria

    Science.gov (United States)

    Sadowsky, Michael J.; Whitman, Richard L.

    2011-01-01

    The Fecal Bacteria offers a balanced, integrated discussion of fecal bacteria and their presence and ecology in the intestinal tract of mammals, in the environment, and in the food supply. This volume covers their use in examining and assessing water quality in order to offer protection from illnesses related to swimming in or ingesting contaminated water, in addition to discussing their use in engineering considerations of water quality, modeling, monitoring, and regulations. Fecal bacteria are additionally used as indicators of contamination of ready-to-eat foods and fresh produce. The intestinal environment, the microbial community structure of the gut microbiota, and the physiology and genomics of this broad group of microorganisms are explored in the book. With contributions from an internationally recognized group of experts, the book integrates medicine, public health, environmental, and microbiological topics in order to provide a unique, holistic understanding of fecal bacteria. Moreover, it shows how the latest basic science and applied research findings are helping to solve problems and develop effective management strategies. For example, readers will discover how the latest tools and molecular approaches have led to our current understanding of fecal bacteria and enabled us to improve human health and water quality. The Fecal Bacteria is recommended for microbiologists, clinicians, animal scientists, engineers, environmental scientists, food safety experts, water quality managers, and students. It will help them better understand fecal bacteria and use their knowledge to protect human and environmental health. They can also apply many of the techniques and molecular tools discussed in this book to the study of a broad range of microorganisms in a variety of habitats.

  11. Structured tradeoffs preference elicitation: Evaluating CRWMS design and operations

    International Nuclear Information System (INIS)

    Preliminary studies over the past few years have yielded multiple design and operations alternatives for the planned Civilian Radioactive Waste Management System (CRWMS). Waste isolation, pre-closure health and safety, and life cycle cost are among the many factors considered in developing these alternatives. The task of CRWMS designers is complicated by substantial heat and nuclear radiation energy output of the spent nuclear fuel and high level waste intended for disposal in an underground repository. Not only must the usual effectiveness, operability and cost objectives be balanced, but done so in the context of a constantly changing environment. Particular alternatives sometimes are favored by virtue of their outstanding performance relative to one of these factors. The Ultimate success of the potential repository, however, depends on reaching a defensible and traceable final decision through simultaneous and systematic weighing of all relevant factors. This paper documents the outcome of Structured Tradeoffs Preference (STP) elicitation as a method for the simultaneous and systematic weighing of factors relevant to repository thermal loading, waste package (WP) design, and emplacement mode decisions. The study provided a low-cost early indication of directions of further research on CRWMS design and operations likely to be most fruitful. The method of STP elicitation was utilized to avoid potential biases documented in other efforts which use only unstructured decision making, or open-quotes well-considered judgmentclose quotes. The STP elicitation procedure presented here complements the use of a parameter network-model pyramid suggested elsewhere in this proceedings to provide a framework for precisely articulating technical questions needing answers. It also forms an independent crosscheck of systems engineering study results and performance assessment modeling

  12. Carrier relaxation time divergence in single and double layer cuprates

    Science.gov (United States)

    Schneider, M. L.; Rast, S.; Onellion, M.; Demsar, J.; Taylor, A. J.; Glinka, Y.; Tolk, N. H.; Ren, Y. H.; Lüpke, G.; Klimov, A.; Xu, Y.; Sobolewski, R.; Si, W.; Zeng, X. H.; Soukiassian, A.; Xi, X. X.; Abrecht, M.; Ariosa, D.; Pavuna, D.; Krapf, A.; Manzke, R.; Printz, J. O.; Williamsen, M. S.; Downum, K. E.; Guptasarma, P.; Bozovic, I.

    2003-12-01

    We report the transient optical pump-probe reflectivity measurements on single and double layer cuprate single crystals and thin films of ten different stoichiometries. We find that with sufficiently low fluence the relaxation time (tauR) of all samples exhibits a power law divergence with temperature (T): tauR ∝ T^{-3 ± 0.5}. Further, the divergence has an onset temperature above the superconducting transition temperature for all superconducting samples. Possible causes of this divergence are discussed.

  13. DIVERGENCE - FREE WAVELET SOLUTION TO THE STOKES PROBLEM

    Institute of Scientific and Technical Information of China (English)

    Yingchun Jiang

    2007-01-01

    In this paper, we use divergence-free wavelets to give an adaptive solution to the velocity field of the Stokes problem. We first use divergence-free wavelets to discretize the divergence-free weak formulation of the Stokes problem and obtain a discrete positive definite linear system of equations whose coefficient matrix is quasi-sparse; Secondly, an adaptive scheme is used to solve the discrete linear system of equations and the error estimation and complexity analysis are given.

  14. Hyperbolic Divergence Cleaning Method for Godunov Smoothed Particle Magnetohydrodynamics

    Science.gov (United States)

    Iwasaki, K.; Inutsuka, S.-I.

    2013-04-01

    In this paper, we implement a divergence cleaning method into Godunov smoothed particle magnetohydrodynamics (GSPM). In the GSPM, to describe MHD shocks accurately, a Riemann solver is applied to the SPH method instead of artificial viscosity and resistivity that have been used in previous works. We confirmed that the divergence cleaning method reduces divergence errors significantly. The performance of the method is demonstrated in the numerical simulations of a strongly magnetized gas and bipolar outflow from the first core.

  15. Repeated adaptive divergence of microhabitat specialization in avian feather lice

    OpenAIRE

    Johnson Kevin P; Shreve Scott M; Smith Vincent S

    2012-01-01

    Abstract Background Repeated adaptive radiations are evident when phenotypic divergence occurs within lineages, but this divergence into different forms is convergent when compared across lineages. Classic examples of such repeated adaptive divergence occur in island (for example, Caribbean Anolis lizards) and lake systems (for example, African cichlids). Host-parasite systems in many respects are analogous to island systems, where host species represent isolated islands for parasites whose l...

  16. Rates of genomic divergence in humans, chimpanzees and their lice

    OpenAIRE

    Johnson, Kevin P.; Allen, Julie M; Olds, Brett P.; Mugisha, Lawrence; Reed, David L; Paige, Ken N.; Pittendrigh, Barry R.

    2014-01-01

    The rate of DNA mutation and divergence is highly variable across the tree of life. However, the reasons underlying this variation are not well understood. Comparing the rates of genetic changes between hosts and parasite lineages that diverged at the same time is one way to begin to understand differences in genetic mutation and substitution rates. Such studies have indicated that the rate of genetic divergence in parasites is often faster than that of their hosts when comparing single genes...

  17. State-Dependent Divergences in the Entanglement Entropy

    CERN Document Server

    Marolf, Donald

    2016-01-01

    We show the entanglement entropy in certain quantum field theories to contain state-dependent divergences. Both perturbative and holographic examples are exhibited. However, quantities such as the relative entropy and the generalized entropy of black holes remain finite, due to cancellation of divergences. We classify all possible state-dependent divergences that can appear in both perturbatively renormalizeable and holographic covariant $d\\le 6$ quantum field theories.

  18. Divergence with gene flow within the recent chipmunk radiation (Tamias)

    OpenAIRE

    Sullivan, J.; Demboski, J R; Bell, K C; Hird, S.; Sarver, B; Reid, N; Good, J M

    2014-01-01

    Increasing data have supported the importance of divergence with gene flow (DGF) in the generation of biological diversity. In such cases, lineage divergence occurs on a shorter timescale than does the completion of reproductive isolation. Although it is critical to explore the mechanisms driving divergence and preventing homogenization by hybridization, it is equally important to document cases of DGF in nature. Here we synthesize data that have accumulated over the last dozen or so years on...

  19. Eliciting Audience's Experience to Improve Interactive Art Installation

    DEFF Research Database (Denmark)

    Baharin, Hanif; Morrison, Ann

    2006-01-01

    Designing with the users in mind is one of the widely accepted design practices in the Interaction Design field. On the other hand, it can be said that audience's experience is the heart of an interactive art. Since Interaction Design has shown that user's involvement in the design process can...... be beneficial, it is speculated that involving the audiences in the creative process of developing an interactive art piece can make the artist improve the art in general and the audience's experience in particular. In this paper, the experience of eliciting the experience of the audiences of an interactive art...

  20. Integrating Effectiveness, Transparency and Fairness into a Value Elicitation Process

    International Nuclear Information System (INIS)

    As part of the evaluation of Canada's proposed nuclear fuel waste disposal concept, the Federal Environmental Assessment and Review Panel (FEARP) undertook an extensive, nation-wide public hearing process. The hearing process itself was contentious and has been criticized on numerous grounds. It is our contention that the fundamental weakness of the FEARP process was that it was designed as an information-based forum, as opposed to a value-based forum.' Our observations and analyses of these hearings indicate that the FEARP envisioned a different purpose and a different outcome of this process than the public in general. As a result, public acceptability for the Concept or even the assessment process itself was not garnered due to a failure in the process to identify, address and incorporate values. To address this, we proposed a seven-step value elicitation process specifically designed to assess public acceptability of the disposal concept. An unfortunate consequence of the flawed public consultation process employed by the FEARP is that it is unclear exactly what it is the public finds unacceptable. Both from discussions and observations, it is difficult to ascertain whether the unacceptability lies with the Concept itself and/or the process by which the Concept was to be assessed. As a result, there is uncertainty as to what questions should be asked and how should the 'unacceptability' be addressed. In other words, does Canada need a new concept? Does Canada need to develop a mechanism for assessing the public acceptability of the Concept? Or both? The inability of the current process to answer such fundamental questions demonstrates the importance of developing an effective public acceptability and consultation process. We submit that, to create an acceptable Public Participation mechanism, it is necessary to found the construction of such a mechanism on the principles of effectiveness, transparency and fairness. Moreover, we believe that the larger decision

  1. Elicited Salience and Salience-Based Level-k

    OpenAIRE

    Wolff, Irenaeus

    2016-01-01

    A level-k model based on a specific salience-pattern is the only model in the literature that accounts for behaviour in hide-and-seek games. This paper presents nine different experiments designed to measure salience. The elicited salience patterns tend to be similar, but none of them is similar to the pattern needed to allow the level-k model explain the hide-and-seek data. When based on any of the empirical salience measures, the salience-based level-k model does not fit the data well. p...

  2. Eliciting Informative Feedback: The Peer-Prediction Method

    Science.gov (United States)

    Miller, Nolan; Resnick, Paul; Zeckhauser, Richard

    Many recommendation and decision processes depend on eliciting evaluations of opportunities, products, and vendors. A scoring system is devised that induces honest reporting of feedback. Each rater merely reports a signal, and the system applies proper scoring rules to the implied posterior beliefs about another rater's report. Honest reporting proves to be a Nash Equilibrium. The scoring schemes can be scaled to induce appropriate effort by raters and can be extended to handle sequential interaction and continuous signals. We also address a number of practical implementation issues that arise in settings such as academic reviewing and on-line recommender and reputation systems.

  3. Expert Panel Elicitation of Seismicity Following Glaciation in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Hora, Stephen; Jensen, Mikael (eds.)

    2005-12-15

    The Swedish Radiation Protection Authority, the Swedish Nuclear Power Inspectorate and the Swedish Nuclear Fuel and Waste Management Company have jointly carried out a project on expert panel elicitation on the issue of glacial induced Swedish earthquakes. Following a broad nomination procedure, 5 experts were chosen by a selection committee of 4 professors within Earth sciences disciplines. The 5 experts presented judgments about the frequency of earthquakes greater the magnitude 6 within 10 km for two Swedish sites, Oskarshamn and Forsmark, in connection with a glaciation cycle. The experts' median value vas 0,1 earthquakes for one glaciation cycle.

  4. Expert Panel Elicitation of Seismicity Following Glaciation in Sweden

    International Nuclear Information System (INIS)

    The Swedish Radiation Protection Authority, the Swedish Nuclear Power Inspectorate and the Swedish Nuclear Fuel and Waste Management Company have jointly carried out a project on expert panel elicitation on the issue of glacial induced Swedish earthquakes. Following a broad nomination procedure, 5 experts were chosen by a selection committee of 4 professors within Earth sciences disciplines. The 5 experts presented judgments about the frequency of earthquakes greater the magnitude 6 within 10 km for two Swedish sites, Oskarshamn and Forsmark, in connection with a glaciation cycle. The experts' median value vas 0,1 earthquakes for one glaciation cycle

  5. Reliability and Security - Convergence or Divergence

    Directory of Open Access Journals (Sweden)

    Emil BURTESCU

    2010-01-01

    Full Text Available Reliability, as every technical field, must adapt to the new demands imposed by reality. Started initially as a field designed to control and ensure the smooth functionality of an element or technical system, reliability has reached the stage where the discussion is about the reliability management, similar to the other top-level fields. Security has its own contribution to the reliability of a system; a reliable system is a system with reliable security. In order for a system to be reliable, that means clear and safe, all its components must be reliable. In the following pages we will talk about the two main facts - reliability and security - to determine both the convergence and the divergence points.

  6. Some Divergence Properties of Asset Price Models

    Directory of Open Access Journals (Sweden)

    Wolfgang Stummer

    2001-12-01

    Full Text Available Abstract: We consider asset price processes Xt which are weak solutions of one-dimensional stochastic differential equations of the form (equation (2 Such price models can be interpreted as non-lognormally-distributed generalizations of the geometric Brownian motion. We study properties of the Iα-divergence between the law of the solution Xt and the corresponding drift-less measure (the special case α=1 is the relative entropy. This will be applied to some context in statistical information theory as well as to arbitrage theory and contingent claim valuation. For instance, the seminal option pricing theorems of Black-Scholes and Merton appear as a special case.

  7. Genetic divergence in land races of rice

    Directory of Open Access Journals (Sweden)

    T.Rajesh, K.Paramasivam and S.Thirumeni

    2010-03-01

    Full Text Available Genetic diversity was assessed in 29 land races of rice using Mahalanobis’s D2 statistics. Eight quantitativecharacters including grain yield were considered for the study. Based on genetic distances, the 29 genotypeswere grouped into five clusters. The mode of distribution of genotypes from different geographic regions intovarious clusters was at random indicating that geographical diversity and genetic diversity were not related .Thecharacters days to first flowering and single plant yield contributed maximum towards genetic divergence. Themaximum inter cluster distance was recorded between cluster IV and cluster V. The genotypes in these clustersVattan and Vellai Chitraikar (cluster IV and Thulasi Manjari (cluster V may serve as potential donors forfuture hybridization programmes.

  8. Ultraviolet divergences in the cyclic Wilson loop and their renormalization

    OpenAIRE

    Berwein, Matthias

    2013-01-01

    We discuss the cyclic Wilson loop, i.e. a rectangular Wilson loop that spans the entire compactified time axis in the imaginary time formalism. The result of a perturbative calculation at $O(\\alpha_s^2)$ is given, with the main focus on the ultraviolet divergences of this operator. Based on a general analysis of divergences in loop diagrams, we find that, unlike usual Wilson loops, the cyclic loop does not have cusp divergences but intersection divergences, where the intersections arise due t...

  9. Suppression effects of Weibel instability for fast electron divergence

    Directory of Open Access Journals (Sweden)

    Sakagami H.

    2013-11-01

    Full Text Available Quasi-static magnetic fields, which are induced by the Weibel instability and grow to more than hundred Megagauss, lead to large divergence angle of fast electrons, hence lower energy coupling. To suppress the divergence, two different structures, namely density trough and punched out holes, are introduced to targets. In the density trough target, the Weibel instability is enhanced and the divergence is getting worse. On the other hand, the divergence angle is improved but the number of electrons is degraded for fast electrons (<3 MeV in the punched out target.

  10. Temperature Influence on Divergence Angles of Quartz Crystal Wollaston Prism

    International Nuclear Information System (INIS)

    We propose a structural angle and main refractive indices as two key factors to understand the temperature influence on the divergence angles of the Wollaston prism. The temperature influence on the divergence angles of quartz crystal Wollaston prism is studied theoretically The results show that divergence angles decrease with increasing temperature, while the divergence angle of e-light decrease more quickly than that of o-light. The testing system is established to verify the above results, and the experimental results are in agreement well with the theoretical analysis. (fundamental areas of phenomenology (including applications))

  11. Sandwiched R\\'enyi Divergence Satisfies Data Processing Inequality

    OpenAIRE

    Beigi, Salman

    2013-01-01

    Sandwiched (quantum) $\\alpha$-R\\'enyi divergence has been recently defined in the independent works of Wilde et al. (arXiv:1306.1586) and M\\"uller-Lennert et al (arXiv:1306.3142v1). This new quantum divergence has already found applications in quantum information theory. Here we further investigate properties of this new quantum divergence. In particular we show that sandwiched $\\alpha$-R\\'enyi divergence satisfies the data processing inequality for all values of $\\alpha> 1$. Moreover we prov...

  12. Protective immunity to H7N9 influenza viruses elicited by synthetic DNA vaccine.

    Science.gov (United States)

    Yan, Jian; Villarreal, Daniel O; Racine, Trina; Chu, Jaemi S; Walters, Jewell N; Morrow, Matthew P; Khan, Amir S; Sardesai, Niranjan Y; Kim, J Joseph; Kobinger, Gary P; Weiner, David B

    2014-05-19

    Despite an intensive vaccine program influenza infections remain a major health problem, due to the viruses' ability to change its envelope glycoprotein hemagglutinin (HA), through shift and drift, permitting influenza to escape protection induced by current vaccines or natural immunity. Recently a new variant, H7N9, has emerged in China causing global concern. First, there have been more than 130 laboratory-confirmed human infections resulting in an alarmingly high death rate (32.3%). Second, genetic changes found in H7N9 appear to be associated with enabling avian influenza viruses to spread more effectively in mammals, thus transmitting infections on a larger scale. Currently, no vaccines or drugs are effectively able to target H7N9. Here, we report the rapid development of a synthetic consensus DNA vaccine (pH7HA) to elicit potent protective immunity against the H7N9 viruses. We show that pH7HA induces broad antibody responses that bind to divergent HAs from multiple new members of the H7N9 family. These antibody responses result in high-titer HAI against H7N9. Simultaneously, this vaccine induces potent polyfunctional effector CD4 and CD8T cell memory responses. Animals vaccinated with pH7HA are completely protected from H7N9 virus infection and any morbidity associated with lethal challenge. This study establishes that this synthetic consensus DNA vaccine represents a new tool for targeting emerging infection, and more importantly, its design, testing and development into seed stock for vaccine production in a few days in the pandemic setting has significant implications for the rapid deployment of vaccines protecting against emerging infectious diseases.

  13. Novel molecular pathways elicited by mutant FGFR2 may account for brain abnormalities in Apert syndrome.

    Directory of Open Access Journals (Sweden)

    Erika Yeh

    Full Text Available Apert syndrome (AS, the most severe form craniosynostosis, is characterized by premature fusion of coronal sutures. Approximately 70% of AS patients carry S252W gain-of-function mutation in FGFR2. Besides the cranial phenotype, brain dysmorphologies are present and are not seen in other FGFR2-asociated craniosynostosis, such as Crouzon syndrome (CS. Here, we hypothesized that S252W mutation leads not only to overstimulation of FGFR2 downstream pathway, but likewise induces novel pathological signaling. First, we profiled global gene expression of wild-type and S252W periosteal fibroblasts stimulated with FGF2 to activate FGFR2. The great majority (92% of the differentially expressed genes (DEGs were divergent between each group of cell populations and they were regulated by different transcription factors. We than compared gene expression profiles between AS and CS cell populations and did not observe correlations. Therefore, we show for the first time that S252W mutation in FGFR2 causes a unique cell response to FGF2 stimulation. Since our gene expression results suggested that novel signaling elicited by mutant FGFR2 might be associated with central nervous system (CNS development and maintenance, we next investigated if DEGs found in AS cells were also altered in the CNS of an AS mouse model. Strikingly, we validated Strc (stereocilin in newborn Fgfr2(S252W/+ mouse brain. Moreover, immunostaining experiments suggest a role for endothelial cells and cerebral vasculature in the establishment of characteristic CNS dysmorphologies in AS that has not been proposed by previous literature. Our approach thus led to the identification of new target genes directly or indirectly associated with FGFR2 which are contributing to the pathophysiology of AS.

  14. Attenuated Salmonella typhimurium carrying shRNA-expressing vectors elicit RNA interference in murine bladder tumors

    Institute of Scientific and Technical Information of China (English)

    Nan YANG; Sheng-hua LI; Yun-zhe L(U); Li-shan CHEN; Da-ming REN

    2011-01-01

    Aim: To examine whether attenuated Salmonella typhimurium (S typhimurium) could be used as an anti-cancer agent or a tumortargeting vehicle for delivering shRNA-expressing pDNA into cancer cells in a mouse tumor model.Methods: Mouse bladder transitional cancer cell line (BTT-T739) expressing GFP was used, in which the GFP expression level served as an indicator of RNA interference (RNAi). BTT-T739-GFP tumor-bearing mice (4-6 weeks) were treated with S typhimurium carrying plasmids encoding shRNA against gfp or scrambled shRNA. The mRNA and protein expression levels of GFP were assessed 5 d after the bacteria administration, and the antitumor effects of S typhimurium were evaluated.Results: In BTT-T739-GFP tumor-bearing mice, S typhirnurium (1×109 cfu, po) preferentially accumulated within tumors for as long as 40 d, and formed a tumor-to-normal tissue ratio that exceeded 1000/1. S typhimurium carrying plasmids encoding shRNA against gfp inhibited the expression of GFP in tumor cells by 73.4%. Orally delivered S typhimurium significantly delayed tumor growth and prolonged the survival of tumor-bearing mice.Conclusion: This study demonstrates that attenuated S typhimurium can be used for both delivering shRNA-expressing vectors into tumor cells and eliciting RNAi, thus exerting anti-tumor activity, which may represent a new strategy for the treatment of solid tumors.

  15. Botanical and biological pesticides elicit a similar Induced Systemic Response in tomato (Solanum lycopersicum) secondary metabolism.

    Science.gov (United States)

    Pretali, Luca; Bernardo, Letizia; Butterfield, Timothy S; Trevisan, Marco; Lucini, Luigi

    2016-10-01

    Natural pesticides have attracted substantial interest due to the increase in organic agriculture and enhanced attention to environmental pollution. Plant Growth Promoting Bacteria (PGPB) are applied for both disease control and growth enhancement; PGPBs are known to elicit Induced Systemic Response (ISR) in plants. However, less is known about the effect of botanical pesticides, such as the azadirachtin-containing neem extracts, on plant metabolism. This study aimed to investigate the effects of foliar application of the above-mentioned natural pesticides on the metabolic profiling of tomato. Leaf application of Bacillus subtilis fostered Induced Systemic Resistance (ISR) in treated plants via the Jasmonic acid pathway, and enhanced production of secondary metabolites such as flavonoids, phytoalexins and auxins. Changes in sterols and terpenes, as well as an increase in glucosinolates were also observed. Interestingly, azadirachtin-treated tomatoes also showed an increase in ISR and our results revealed that most of the enriched metabolites are shared with a B. subtilis treatment, suggesting conserved biochemical responses. These (un)expected findings indicate that plants are not insensitive to application of natural pesticide and while Azadirachtin is applied as a direct pesticide, it also stimulates a defense response in tomatoes very similar to B. subtilis induced ISR. PMID:27251587

  16. Anaerobic bacteria in otitis media.

    Science.gov (United States)

    Fulghum, R S; Daniel, H J; Yarborough, J G

    1977-01-01

    Anaerobic bacteria, Peptostrepotococcus intermedius and Propionibacterium acnes, were found in mixed culture specimens from four to ten tested cases of chronic secretory otitis media. These anaerobic bacteria were in a mixed infection flora with aerobic bacteria most often Staphylococcus epidermidis and Cornybacterium sp. which do not fit any established species. The findings of anaerobic bacteria in otitis media is consistent with the sporadic report of the involvement of anaerobic bacteria in otitis media in the literature since 1898.

  17. Eliciting and communicating expert judgments: Methodology and application to nuclear safety

    International Nuclear Information System (INIS)

    The most ambitious and certainly the most extensive formal expert judgment process was the elicitation of numerous events and uncertain quantities for safety issues in five nuclear power plants in the U.S. The general methodology for formal expert elicitations are described. An overview of the expert elicitation process of NUREG 1150 is provided and the elicitation of probabilities for the interfacing systems loss of coolant accident LOCA (ISL) in PWRs is given as an example of this elicitation process. Some lessons learned from this study are presented. (DG)

  18. Expert Elicitation Survey on Future Wind Energy Costs

    Energy Technology Data Exchange (ETDEWEB)

    Wiser, Ryan; Jenni, Karen; Seel, Joachim; Baker, Erin; Hand, Maureen; Lantz, Eric; Smith, Aaron

    2016-09-12

    Wind energy supply has grown rapidly over the last decade. However, the long-term contribution of wind to future energy supply, and the degree to which policy support is necessary to motivate higher levels of deployment, depends -- in part -- on the future costs of both onshore and offshore wind. Here, we summarize the results of an expert elicitation survey of 163 of the world's foremost wind experts, aimed at better understanding future costs and technology advancement possibilities. Results suggest significant opportunities for cost reductions, but also underlying uncertainties. Under the median scenario, experts anticipate 24-30% reductions by 2030 and 35-41% reductions by 2050 across the three wind applications studied. Costs could be even lower: experts predict a 10% chance that reductions will be more than 40% by 2030 and more than 50% by 2050. Insights gained through expert elicitation complement other tools for evaluating cost-reduction potential, and help inform policy and planning, R&D and industry strategy.

  19. Emotion elicitation: A comparison of pictures and films

    Directory of Open Access Journals (Sweden)

    Meike Katrin Uhrig

    2016-02-01

    Full Text Available AbstractPictures and film clips are widely used and accepted stimuli to elicit emotions. Based on theoretical arguments it is often assumed that the emotional effects of films exceed those of pictures, but to date this assumption has not been investigated directly. The aim of the present study was to compare pictures and films in terms of their capacity to induce emotions verified by means of explicit measures. Stimuli were (a single pictures presented for 6 s, (b a set of three consecutive pictures with emotionally congruent contents presented for 2 s each, (c short film clips with a duration of 6 s. A total of 144 participants rated their emotion and arousal states following stimulus presentation. Repeated-measures ANOVAs revealed that the film clips and 3-picture version were as effective as the classical 1-picture method to elicit positive emotions, however, modulation towards positive valence was little. Modulation toward negative valence was more effective in general. Film clips were less effective than pictorial stimuli in producing the corresponding emotion states (all p < .001 and were less arousing (all p ≤ .02. Possible reasons for these unexpected results are discussed.

  20. Hypoglycemic activity of withanolides and elicitated Withania somnifera.

    Science.gov (United States)

    Gorelick, Jonathan; Rosenberg, Rivka; Smotrich, Avinoam; Hanuš, Lumír; Bernstein, Nirit

    2015-08-01

    Withania somnifera, known in India as Asghawhanda, is used traditionally to treat many medical problems including diabetes and has demonstrated therapeutic activity in various animal models as well as in diabetic patients. While much of W. somnifera's therapeutic activity is attributed to withanolides, their role in the anti-diabetic activity of W. somnifera has not been adequately studied. In the present study, we evaluated the anti-diabetic activity of W. somnifera extract and purified withanolides, as well as the effect of various elicitors on this activity. W. somnifera leaf and root extracts increased glucose uptake in myotubes and adipocytes in a dose dependent manner, with the leaf extract more active than the root extract. Leaf but not root extract increased insulin secretion in basal pancreatic beta cells but not in stimulated cells. Six withanolides isolated from W. somnifera were tested for anti-diabetic activity based on glucose uptake in skeletal myotubes. Withaferin A was found to increase glucose uptake, with 10μM producing a 54% increase compared with control, suggesting that withaferin A is at least partially responsible for W. somnifera's anti-diabetic activity. Elicitors applied to the root growing solutions affected the physiological state of the plants, altering membrane leakage or osmotic potential. Methyl salicylate and chitosan increased withaferin A content by 75% and 69% respectively, and extracts from elicited plants increased glucose uptake to a higher extent than non-elicited plants, demonstrating a correlation between increased content of withaferin A and anti-diabetic activity.

  1. Investigation on Divergent Exit Curvature Effect on Nozzle Pressure Ratio of Supersonic Convergent Divergent Nozzle

    OpenAIRE

    aShyamshankar.M.B; Sankar.V

    2015-01-01

    The objective of this project work is to computationally analyze shock waves in the Convergent Divergent (CD) Nozzle. The commercial CFD code Fluent is employed to analyze the compressible flow through the nozzle. The analysis is about NPR (Nozzle Pressure Ratio) i.e., the ratio between exit pressure of the nozzle to ambient pressure. The various models of CD Nozzle are designed and the results are compared. The flow characteristic of shockwave for various design of CD Nozzle is a...

  2. Metric Redefinition and UV Divergences in Quantum Einstein Gravity

    CERN Document Server

    Solodukhin, Sergey N

    2015-01-01

    I formulate several statements demonstrating that the local metric redefinition can be used to reduce the UV divergences present in the quantum action for the Einstein gravity in $d=4$ dimensions. In its most general form, the proposal is that any UV divergences in the quantum action can be removed by an appropriate field re-definition and a renormalization of cosmological constant.

  3. Divergence and Convergence between Oral and Written Communication.

    Science.gov (United States)

    Rubin, Donald L.

    1987-01-01

    Differences and similarities between oral and written communication as applied to writing instruction are discussed with examples of divergent oral and written styles among speakers of nonstandard dialects, code switching between speech and writing, convergence and divergence in the development of writing skills, and the role of talking in writing…

  4. Measurements of Wind Divergence with Volume Imaging Lidar

    Science.gov (United States)

    Young, P. W.; Eloranta, E. W.

    1992-01-01

    Mesoscale horizontal divergence and vertical motion in the boundary layer are key ingredients in atmospheric and climate modeling. These quantities are very difficult to measure. This paper presents a technique for determining the divergence over a 10 km x 5 km area from lidar images depicting the spatial distribution of the naturally occurring atmospheric aerosols.

  5. Properties of classical and quantum Jensen-Shannon divergence

    Science.gov (United States)

    Briët, Jop; Harremoës, Peter

    2009-05-01

    Jensen-Shannon divergence (JD) is a symmetrized and smoothed version of the most important divergence measure of information theory, Kullback divergence. As opposed to Kullback divergence it determines in a very direct way a metric; indeed, it is the square of a metric. We consider a family of divergence measures ( JDα for α>0 ), the Jensen divergences of order α , which generalize JD as JD1=JD . Using a result of Schoenberg, we prove that JDα is the square of a metric for αɛ(0,2] , and that the resulting metric space of probability distributions can be isometrically embedded in a real Hilbert space. Quantum Jensen-Shannon divergence (QJD) is a symmetrized and smoothed version of quantum relative entropy and can be extended to a family of quantum Jensen divergences of order α (QJDα) . We strengthen results by Lamberti and co-workers by proving that for qubits and pure states, QJDα1/2 is a metric space which can be isometrically embedded in a real Hilbert space when αɛ(0,2] . In analogy with Burbea and Rao’s generalization of JD, we also define general QJD by associating a Jensen-type quantity to any weighted family of states. Appropriate interpretations of quantities introduced are discussed and bounds are derived in terms of the total variation and trace distance.

  6. On bounds of some dynamic information divergence measures

    Directory of Open Access Journals (Sweden)

    S. M. Sunoj

    2013-05-01

    Full Text Available In this paper, we obtain certain bounds for some dynamic information divergences measures viz. Renyi’s divergence of order α and Kerridge’s inaccuracy, using likelihood ratio ordering. The results are also extended to weighted models and theoretical examples are given to supplement the results.

  7. Maps on Quantum States Preserving Bregman and Jensen Divergences

    Science.gov (United States)

    Virosztek, Dániel

    2016-09-01

    We describe the structure of the bijective transformations on the set of density operators which preserve the Bregman f-divergence for an arbitrary differentiable strictly convex function f. Furthermore, we determine the preservers of the Jensen f-divergence in the case when the generating function f belongs to a recently introduced function class called Matrix Entropy Class.

  8. Metric redefinition and UV divergences in quantum Einstein gravity

    Science.gov (United States)

    Solodukhin, Sergey N.

    2016-03-01

    I formulate several statements demonstrating that the local metric redefinition can be used to reduce the UV divergences present in the quantum action for the Einstein gravity in d = 4 dimensions. In its most general form, the proposal is that any UV divergences in the quantum action can be removed by an appropriate field re-definition and a renormalization of cosmological constant.

  9. Metric redefinition and UV divergences in quantum Einstein gravity

    OpenAIRE

    Solodukhin, Sergey N.

    2016-01-01

    I formulate several statements demonstrating that the local metric redefinition can be used to reduce the UV divergences present in the quantum action for the Einstein gravity in $d=4$ dimensions. In its most general form, the proposal is that any UV divergences in the quantum action can be removed by an appropriate field re-definition and a renormalization of cosmological constant.

  10. Turbulent boundary layer over a convergent and divergent superhydrophobic surface

    Science.gov (United States)

    Nadeem, Muhammad; Hwang, Jinyul; Sung, Hyung Jin

    2015-11-01

    Direct numerical simulation (DNS) of spatially developing turbulent boundary layer (TBL) over a convergent and divergent superhydrophobic surface (SHS) was performed. The convergent and divergent SHS was aligned in the streamwise direction. The SHS was modeled as a pattern of slip and no-slip surfaces. For comparison, DNS of TBL over a straight SHS was also carried out. The momentum thickness Reynolds number was varied from 800 to 1400. The gas fraction of the convergent and divergent SHS was the same as that of the straight SHS, keeping the slip area constant. The slip velocity in the convergent SHS was higher than that of the straight SHS. An optimal streamwise length of the convergent and divergent SHS was obtained. The convergent and divergent SHS gave more drag reduction than the straight SHS. The convergent and divergent SHS led to the modification of near wall-turbulent structures, resembling the narrowing and widening streaky structures near the wall. The convergent and divergent SHS had a relatively larger damping effect on near-wall turbulence than the straight SHS. These observations will be further analyzed statistically to demonstrate the effect of the convergent and divergent SHS on the interaction of inner and outer regions of TBL.

  11. Parametric R-norm directed-divergence convex function

    Science.gov (United States)

    Garg, Dhanesh; Kumar, Satish

    2016-06-01

    In this paper, we define parametric R-norm directed-divergence convex function and discuss their special cases and prove some properties similar to Kullback-Leibler information measure. From R-norm divergence measure new information measures have also been derived and their relations with different measures of entropy have been obtained and give its application in industrial engineering.

  12. Cultural Divergence Related to Urban Proximity on American Indian Reservations.

    Science.gov (United States)

    Price, John A.

    The scattered reservation segments of a single U.S. or Canadian Indian tribe have often culturally diverged from one another in recent historical times. This divergence is particularly marked in more urban regions, such as California, and among tribes where some of the reservations are near cities. As tribalism has become less important and urban…

  13. Mycophagous soil bacteria

    NARCIS (Netherlands)

    Rudnick, M.B.

    2015-01-01

    Abstract

    Soil microorganisms evolved several strategies to compete for limited nutrients in soil. Bacteria of the genus Collimonas developed a way to exploit fungi as a source of organic nutrients. This strategy has been termed “mycophagy&r

  14. Exceptional giftedness in early adolescence and intrafamilial divergent thinking.

    Science.gov (United States)

    Runco, M A; Albert, R S

    1986-08-01

    Two groups of boys and their parents (N=54) were given five divergent thinking tests as one part of a longitudinal investigation on exceptional giftedness in early adolescence. One groups of adolescents was selected because their IQs were above 150, and the other group, was selected because of their outstanding math-science abilities. Canonical and bivariate analyses indicated that there was a strong correlation between the adolescents' divergent thinking test scores and their parents' divergent thinking test scores (Rc=.55). Additionally, there was some indication that these correlations differed in the two exceptionally gifted groups, with the high-IQ group having divergent thinking test scores related to those of both parents, and the math-science group having divergent thinking test scores related only to those of their mothers. These findings are very consistent with earlier investigations on exceptionally gifted adolescents.

  15. Divergent clonal selection dominates medulloblastoma at recurrence.

    Science.gov (United States)

    Morrissy, A Sorana; Garzia, Livia; Shih, David J H; Zuyderduyn, Scott; Huang, Xi; Skowron, Patryk; Remke, Marc; Cavalli, Florence M G; Ramaswamy, Vijay; Lindsay, Patricia E; Jelveh, Salomeh; Donovan, Laura K; Wang, Xin; Luu, Betty; Zayne, Kory; Li, Yisu; Mayoh, Chelsea; Thiessen, Nina; Mercier, Eloi; Mungall, Karen L; Ma, Yusanne; Tse, Kane; Zeng, Thomas; Shumansky, Karey; Roth, Andrew J L; Shah, Sohrab; Farooq, Hamza; Kijima, Noriyuki; Holgado, Borja L; Lee, John J Y; Matan-Lithwick, Stuart; Liu, Jessica; Mack, Stephen C; Manno, Alex; Michealraj, K A; Nor, Carolina; Peacock, John; Qin, Lei; Reimand, Juri; Rolider, Adi; Thompson, Yuan Y; Wu, Xiaochong; Pugh, Trevor; Ally, Adrian; Bilenky, Mikhail; Butterfield, Yaron S N; Carlsen, Rebecca; Cheng, Young; Chuah, Eric; Corbett, Richard D; Dhalla, Noreen; He, An; Lee, Darlene; Li, Haiyan I; Long, William; Mayo, Michael; Plettner, Patrick; Qian, Jenny Q; Schein, Jacqueline E; Tam, Angela; Wong, Tina; Birol, Inanc; Zhao, Yongjun; Faria, Claudia C; Pimentel, José; Nunes, Sofia; Shalaby, Tarek; Grotzer, Michael; Pollack, Ian F; Hamilton, Ronald L; Li, Xiao-Nan; Bendel, Anne E; Fults, Daniel W; Walter, Andrew W; Kumabe, Toshihiro; Tominaga, Teiji; Collins, V Peter; Cho, Yoon-Jae; Hoffman, Caitlin; Lyden, David; Wisoff, Jeffrey H; Garvin, James H; Stearns, Duncan S; Massimi, Luca; Schüller, Ulrich; Sterba, Jaroslav; Zitterbart, Karel; Puget, Stephanie; Ayrault, Olivier; Dunn, Sandra E; Tirapelli, Daniela P C; Carlotti, Carlos G; Wheeler, Helen; Hallahan, Andrew R; Ingram, Wendy; MacDonald, Tobey J; Olson, Jeffrey J; Van Meir, Erwin G; Lee, Ji-Yeoun; Wang, Kyu-Chang; Kim, Seung-Ki; Cho, Byung-Kyu; Pietsch, Torsten; Fleischhack, Gudrun; Tippelt, Stephan; Ra, Young Shin; Bailey, Simon; Lindsey, Janet C; Clifford, Steven C; Eberhart, Charles G; Cooper, Michael K; Packer, Roger J; Massimino, Maura; Garre, Maria Luisa; Bartels, Ute; Tabori, Uri; Hawkins, Cynthia E; Dirks, Peter; Bouffet, Eric; Rutka, James T; Wechsler-Reya, Robert J; Weiss, William A; Collier, Lara S; Dupuy, Adam J; Korshunov, Andrey; Jones, David T W; Kool, Marcel; Northcott, Paul A; Pfister, Stefan M; Largaespada, David A; Mungall, Andrew J; Moore, Richard A; Jabado, Nada; Bader, Gary D; Jones, Steven J M; Malkin, David; Marra, Marco A; Taylor, Michael D

    2016-01-21

    The development of targeted anti-cancer therapies through the study of cancer genomes is intended to increase survival rates and decrease treatment-related toxicity. We treated a transposon-driven, functional genomic mouse model of medulloblastoma with 'humanized' in vivo therapy (microneurosurgical tumour resection followed by multi-fractionated, image-guided radiotherapy). Genetic events in recurrent murine medulloblastoma exhibit a very poor overlap with those in matched murine diagnostic samples (<5%). Whole-genome sequencing of 33 pairs of human diagnostic and post-therapy medulloblastomas demonstrated substantial genetic divergence of the dominant clone after therapy (<12% diagnostic events were retained at recurrence). In both mice and humans, the dominant clone at recurrence arose through clonal selection of a pre-existing minor clone present at diagnosis. Targeted therapy is unlikely to be effective in the absence of the target, therefore our results offer a simple, proximal, and remediable explanation for the failure of prior clinical trials of targeted therapy. PMID:26760213

  16. Region segmentation using information divergence measures.

    Science.gov (United States)

    Hibbard, Lyndon S

    2004-09-01

    Image segmentations based on maximum likelihood or maximum a posteriori analyses of object textures usually assume parametric models (e.g., Gaussian) for distributions of these features. For real images, parameter accuracy and model stationarity may be elusive, so that model-free inference methods ought to have an advantage over those that are model-dependent. Functions of the relative entropy (RE) from information theory can produce minimum error, model-free inferences, and can detect the boundary of an image object by maximizing the RE between the pixel distributions inside and outside a flexible curve contour. A generalization of the RE -- the Jensen-Rényi divergence (JRD) -- computes optimal n-way decisions and can contour multiple objects in an image simultaneously. Seed regions expand naturally and multiple contours tend not to overlap. An edge detector based on the JRD, combined with multivariate pixel segmentation, generally improved the error of the segmentation. We apply these functions to contour patient anatomy in X-ray computed tomography for radiotherapy treatment planning.

  17. Divergent clonal selection dominates medulloblastoma at recurrence

    Science.gov (United States)

    Morrissy, A. Sorana; Garzia, Livia; Shih, David J. H.; Zuyderduyn, Scott; Huang, Xi; Skowron, Patryk; Remke, Marc; Cavalli, Florence M. G.; Ramaswamy, Vijay; Lindsay, Patricia E.; Jelveh, Salomeh; Donovan, Laura K.; Wang, Xin; Luu, Betty; Zayne, Kory; Li, Yisu; Mayoh, Chelsea; Thiessen, Nina; Mercier, Eloi; Mungall, Karen L.; Ma, Yusanne; Tse, Kane; Zeng, Thomas; Shumansky, Karey; Roth, Andrew J. L.; Shah, Sohrab; Farooq, Hamza; Kijima, Noriyuki; Holgado, Borja L.; Lee, John J. Y.; Matan-Lithwick, Stuart; Liu, Jessica; Mack, Stephen C.; Manno, Alex; Michealraj, K. A.; Nor, Carolina; Peacock, John; Qin, Lei; Reimand, Juri; Rolider, Adi; Thompson, Yuan Y.; Wu, Xiaochong; Pugh, Trevor; Ally, Adrian; Bilenky, Mikhail; Butterfield, Yaron S. N.; Carlsen, Rebecca; Cheng, Young; Chuah, Eric; Corbett, Richard D.; Dhalla, Noreen; He, An; Lee, Darlene; Li, Haiyan I.; Long, William; Mayo, Michael; Plettner, Patrick; Qian, Jenny Q.; Schein, Jacqueline E.; Tam, Angela; Wong, Tina; Birol, Inanc; Zhao, Yongjun; Faria, Claudia C.; Pimentel, José; Nunes, Sofia; Shalaby, Tarek; Grotzer, Michael; Pollack, Ian F.; Hamilton, Ronald L.; Li, Xiao-Nan; Bendel, Anne E.; Fults, Daniel W.; Walter, Andrew W.; Kumabe, Toshihiro; Tominaga, Teiji; Collins, V. Peter; Cho, Yoon-Jae; Hoffman, Caitlin; Lyden, David; Wisoff, Jeffrey H.; Garvin, James H.; Stearns, Duncan S.; Massimi, Luca; Schüller, Ulrich; Sterba, Jaroslav; Zitterbart, Karel; Puget, Stephanie; Ayrault, Olivier; Dunn, Sandra E.; Tirapelli, Daniela P. C.; Carlotti, Carlos G.; Wheeler, Helen; Hallahan, Andrew R.; Ingram, Wendy; MacDonald, Tobey J.; Olson, Jeffrey J.; Van Meir, Erwin G.; Lee, Ji-Yeoun; Wang, Kyu-Chang; Kim, Seung-Ki; Cho, Byung-Kyu; Pietsch, Torsten; Fleischhack, Gudrun; Tippelt, Stephan; Ra, Young Shin; Bailey, Simon; Lindsey, Janet C.; Clifford, Steven C.; Eberhart, Charles G.; Cooper, Michael K.; Packer, Roger J.; Massimino, Maura; Garre, Maria Luisa; Bartels, Ute; Tabori, Uri; Hawkins, Cynthia E.; Dirks, Peter; Bouffet, Eric; Rutka, James T.; Wechsler-Reya, Robert J.; Weiss, William A.; Collier, Lara S.; Dupuy, Adam J.; Korshunov, Andrey; Jones, David T. W.; Kool, Marcel; Northcott, Paul A.; Pfister, Stefan M.; Largaespada, David A.; Mungall, Andrew J.; Moore, Richard A.; Jabado, Nada; Bader, Gary D.; Jones, Steven J. M.; Malkin, David; Marra, Marco A.; Taylor, Michael D.

    2016-01-01

    The development of targeted anti-cancer therapies through the study of cancer genomes is intended to increase survival rates and decrease treatment-related toxicity. We treated a transposon–driven, functional genomic mouse model of medulloblastoma with ‘humanized’ in vivo therapy (microneurosurgical tumour resection followed by multi-fractionated, image-guided radiotherapy). Genetic events in recurrent murine medulloblastoma exhibit a very poor overlap with those in matched murine diagnostic samples (<5%). Whole-genome sequencing of 33 pairs of human diagnostic and post-therapy medulloblastomas demonstrated substantial genetic divergence of the dominant clone after therapy (<12% diagnostic events were retained at recurrence). In both mice and humans, the dominant clone at recurrence arose through clonal selection of a pre-existing minor clone present at diagnosis. Targeted therapy is unlikely to be effective in the absence of the target, therefore our results offer a simple, proximal, and remediable explanation for the failure of prior clinical trials of targeted therapy. PMID:26760213

  18. Diversity and Divergence of Dinoflagellate Histone Proteins.

    Science.gov (United States)

    Marinov, Georgi K; Lynch, Michael

    2015-12-08

    Histone proteins and the nucleosomal organization of chromatin are near-universal eukaroytic features, with the exception of dinoflagellates. Previous studies have suggested that histones do not play a major role in the packaging of dinoflagellate genomes, although several genomic and transcriptomic surveys have detected a full set of core histone genes. Here, transcriptomic and genomic sequence data from multiple dinoflagellate lineages are analyzed, and the diversity of histone proteins and their variants characterized, with particular focus on their potential post-translational modifications and the conservation of the histone code. In addition, the set of putative epigenetic mark readers and writers, chromatin remodelers and histone chaperones are examined. Dinoflagellates clearly express the most derived set of histones among all autonomous eukaryote nuclei, consistent with a combination of relaxation of sequence constraints imposed by the histone code and the presence of numerous specialized histone variants. The histone code itself appears to have diverged significantly in some of its components, yet others are conserved, implying conservation of the associated biochemical processes. Specifically, and with major implications for the function of histones in dinoflagellates, the results presented here strongly suggest that transcription through nucleosomal arrays happens in dinoflagellates. Finally, the plausible roles of histones in dinoflagellate nuclei are discussed.

  19. Divergence-free Hardy space on

    Institute of Scientific and Technical Information of China (English)

    LOU; Zengjian

    2004-01-01

    [1]Gilbert, J. E., Hogan, J. A., Lakey, J. D., Atomic decomposition of divergence-free Hardy spaces, Mathematica Moraviza, 1997, Special Volume, Proc. IWAA: 33-52.[2]Chang, D. C., Krantz, S. G., Stein, E. M., HP theory on a smooth domain in RN and elliptic boundary value problems, J. Funct. Anal., 1993, 114: 286-347.[3]Schwarz, G., Hodge Decomposition-A method for solving boundary value problems, Lecture Notes in Mathematics, Vol. 1607, Berlin Heidelberg: Springer-Verlag, 1995.[4]Girault, V., Raviart, P. A., Finite Element Methods for Navier-Stokes Equations, Theory and Algorithms, Berlin Heidelberg: Springer-Verlag, 1986.[5]Stein, E. M., Singular Integrals and Differentiability Properties of Functions, Princeton: Princeton Univ. Press,1970.[6]Davies, B., Heat Kernels and Spectral Theory, Cambridge: Cambridge University Press, 1989.[7]Geymonat, G., Miller, S., Triantafylidis, N., Homogenization of nonlinear elastic materials, microscopic bifurcation and microscopic loss of rank-one convexity, Arch. Rational Mech. Anal., 1993, 122: 231-290.[8]Ball, J., Convexity conditions and existence theorems in nonlinear elasticity, Arch. Rational Mech. Anal., 1977,63: 337-403.[9]Zhang, K., On the coercivity of elliptic systems in two dimensional spaces, Bull. Austral. Math. Soc., 1996, 54:423-430.

  20. Molecular mimicry and horror autotoxicus: do chlamydial infections elicit autoimmunity?

    Science.gov (United States)

    Swanborg, Robert H; Boros, Dov L; Whittum-Hudson, Judith A; Hudson, Alan P

    2006-11-30

    All species of the order Chlamydiales are obligate intracellular eubacterial pathogens of their various hosts. Two chlamydial species, Chlamydia trachomatis and Chlamydia pneumoniae, are primarily human pathogens, and each is known to cause important diseases. Some strains of C. trachomatis are sexually transmitted and frequently cause severe reproductive problems, primarily in women. Other strains of the organism serve as the aetiological agents for blinding trachoma, still the leading cause of preventable blindness in underdeveloped nations. C. pneumoniae is a respiratory pathogen known to cause community-acquired pneumonia. Importantly, both organisms engender an immunopathogenic response in the human host, and both have been associated with widely diverse, relatively common and currently idiopathic chronic diseases, most of which include an important autoimmune component. In this article, we explore the available experimental data regarding the possible elicitation of autoimmunity in various contexts by chlamydial infection, and we suggest several avenues for research to explore this potentially important issue further.

  1. Cripto-1 vaccination elicits protective immunity against metastatic melanoma.

    Science.gov (United States)

    Ligtenberg, M A; Witt, K; Galvez-Cancino, F; Sette, A; Lundqvist, A; Lladser, A; Kiessling, R

    2016-05-01

    Metastatic melanoma is a fatal disease that responds poorly to classical treatments but can be targeted by T cell-based immunotherapy. Cancer vaccines have the potential to generate long-lasting cytotoxic CD8(+) T cell responses able to eradicate established and disseminated tumors. Vaccination against antigens expressed by tumor cells with enhanced metastatic potential represents a highly attractive strategy to efficiently target deadly metastatic disease. Cripto-1 is frequently over-expressed in human carcinomas and melanomas, but is expressed only at low levels on normal differentiated tissues. Cripto-1 is particularly upregulated in cancer-initiating cells and is involved in cellular processes such as cell migration, invasion and epithelial-mesenchymal transition, which are hallmarks of aggressive cancer cells able to initiate metastatic disease. Here, we explored the potential of Cripto-1 vaccination to target metastatic melanoma in a preclinical model. Cripto-1 was overexpressed in highly metastatic B16F10 cells as compared to poorly metastatic B16F1 cells. Moreover, B16F10 cells grown in sphere conditions to enrich for cancer stem cells (CSC) progressively upregulated cripto1 expression. Vaccination of C57Bl/6 mice with a DNA vaccine encoding mouse Cripto-1 elicited a readily detectable/strong cytotoxic CD8(+) T cell response specific for a H-2 Kb-restricted epitope identified based on its ability to bind H-2(b) molecules. Remarkably, Cripto-1 vaccination elicited a protective response against lung metastasis and subcutaneous challenges with highly metastatic B16F10 melanoma cells. Our data indicate that vaccination against Cripto-1 represents a novel strategy to be tested in the clinic. PMID:27467944

  2. Knowledge elicitation techniques and application to nuclear plant maintenance

    Science.gov (United States)

    Doyle, E. Kevin

    The new millennium has brought with it the opportunity of global trade which in turn requires the utmost in efficiency from each individual industry. This includes the nuclear power industry, a point which was emphasized when the electrical generation industry began to be de regulated across North America the late 1990s and re-emphasized when the northeast power grid of North America collapsed in the summer of 2003. This dissertation deals with reducing the cost of the maintenance function of Candu nuclear power plants and initiating a strong link between universities and the Canadian nuclear industry. Various forms of RCM (reliability-centred maintenance) have been the tools of choice in industry for improving the maintenance function during the last 20 years. In this project, pilot studies, conducted at Bruce Power between 1999 and 2005, and reported on in this dissertation, lay out a path to implement statistical improvements as the next step after RCM in reducing the cost of the maintenance. Elicitation protocols, designed for the age group being elicited, address the much-documented issue of a lack of data. Clear, graphical, inferential statistical interfaces are accentuated and developed to aid in building the teams required to implement the various methodologies and to help in achieving funding targets. Graphical analysis and Crow/AMSAA (army materials systems analysis activity) plots are developed and demonstrated from the point of view of justifying the expenditures of cost reduction efforts. This dissertation ultimately speaks to the great opportunity being presented by this approach at this time: of capturing the baby-boom generation's huge pool of knowledge before those people retire. It is expected that the protocols and procedures referenced here will have applicability across the many disciplines where collecting expert information from a similar age group is required.

  3. Can bacteria save the planet?

    OpenAIRE

    Hunter, Philip

    2010-01-01

    Bacteria might just hold the key to preserving the environment for our great grandchildren. Philip Hunter explores some of the novel ways in which systems biology and biotechnology are harnessing bacteria to produce renewable energy and clean up pollution.

  4. Manufacture of Probiotic Bacteria

    Science.gov (United States)

    Muller, J. A.; Ross, R. P.; Fitzgerald, G. F.; Stanton, C.

    Lactic acid bacteria (LAB) have been used for many years as natural biopreservatives in fermented foods. A small group of LAB are also believed to have beneficial health effects on the host, so called probiotic bacteria. Probiotics have emerged from the niche industry from Asia into European and American markets. Functional foods are one of the fastest growing markets today, with estimated growth to 20 billion dollars worldwide by 2010 (GIA, 2008). The increasing demand for probiotics and the new food markets where probiotics are introduced, challenges the industry to produce high quantities of probiotic cultures in a viable and stable form. Dried concentrated probiotic cultures are the most convenient form for incorporation into functional foods, given the ease of storage, handling and transport, especially for shelf-stable functional products. This chapter will discuss various aspects of the challenges associated with the manufacturing of probiotic cultures.

  5. Lipoprotein sorting in bacteria.

    Science.gov (United States)

    Okuda, Suguru; Tokuda, Hajime

    2011-01-01

    Bacterial lipoproteins are synthesized as precursors in the cytoplasm and processed into mature forms on the cytoplasmic membrane. A lipid moiety attached to the N terminus anchors these proteins to the membrane surface. Many bacteria are predicted to express more than 100 lipoproteins, which play diverse functions on the cell surface. The Lol system, composed of five proteins, catalyzes the localization of Escherichia coli lipoproteins to the outer membrane. Some lipoproteins play vital roles in the sorting of other lipoproteins, lipopolysaccharides, and β-barrel proteins to the outer membrane. On the basis of results from biochemical, genetic, and structural studies, we discuss the biogenesis of lipoproteins in bacteria, their importance in cellular functions, and the molecular mechanisms underlying efficient sorting of hydrophobic lipoproteins to the outer membrane through the hydrophilic periplasm. PMID:21663440

  6. Exopolysaccharides from Marine Bacteria

    Institute of Scientific and Technical Information of China (English)

    CHI Zhenming; FANG Yan

    2005-01-01

    Microbial polysaccharides represent a class of important products of growing interest for many sectors of industry. In recent years, there has been a growing interest in isolating new exopolysaccharides (EPSs)-producing bacteria from marine environments, particularly from various extreme marine environments. Many new marine microbial EPSs with novel chemical compositions, properties and structures have been found to have potential applications in fields such as adhesives,textiles, pharmaceuticals and medicine for anti-cancer, food additives, oil recovery and metal removal in mining and industrial waste treatments, etc This paper gives a brief summary of the information about the EPSs produced by marine bacteria,including their chemical compositions, properties and structures, together with their potential applications in industry.

  7. Total Bregman Divergence and its Applications to Shape Retrieval.

    Science.gov (United States)

    Liu, Meizhu; Vemuri, Baba C; Amari, Shun-Ichi; Nielsen, Frank

    2010-01-01

    Shape database search is ubiquitous in the world of biometric systems, CAD systems etc. Shape data in these domains is experiencing an explosive growth and usually requires search of whole shape databases to retrieve the best matches with accuracy and efficiency for a variety of tasks. In this paper, we present a novel divergence measure between any two given points in [Formula: see text] or two distribution functions. This divergence measures the orthogonal distance between the tangent to the convex function (used in the definition of the divergence) at one of its input arguments and its second argument. This is in contrast to the ordinate distance taken in the usual definition of the Bregman class of divergences [4]. We use this orthogonal distance to redefine the Bregman class of divergences and develop a new theory for estimating the center of a set of vectors as well as probability distribution functions. The new class of divergences are dubbed the total Bregman divergence (TBD). We present the l1-norm based TBD center that is dubbed the t-center which is then used as a cluster center of a class of shapes The t-center is weighted mean and this weight is small for noise and outliers. We present a shape retrieval scheme using TBD and the t-center for representing the classes of shapes from the MPEG-7 database and compare the results with other state-of-the-art methods in literature.

  8. Divergences in the vacuum energy for frequency-dependent interactions

    Science.gov (United States)

    Vassilevich, D. V.

    2009-03-01

    We propose a method for determining ultraviolet divergences in the vacuum energy for systems whose spectrum of perturbations is defined through a nonlinear spectrum problem, i.e., when the fluctuation operator itself depends on the frequency. The method is applied to the plasma shell model, which describes some properties of the interaction of electromagnetic field with fullerenes. We formulate a scalar model, which simplifies the matrix structure, but keeps the frequency dependence of the plasma shell, and calculate the ultraviolet divergences in the case when the plasma sheet is slightly curved. The divergent terms are expressed in terms of surface integrals of corresponding invariants.

  9. Divergences in the vacuum energy for frequency-dependent interactions

    CERN Document Server

    Vassilevich, D V

    2009-01-01

    We propose a method for determining ultra-violet divergences in the vacuum energy for systems whose spectrum of perturbations is defined through a non-linear spectrum problem, i.e, when the fluctuation operator itself depends on the frequency. The method is applied to the plasma shell model, which describes some properties of the interaction of electromagnetic field with fullerens. We formulate a scalar model, which simplifies the matrix structure, but keeps the frequency dependence of the plasma shell, and calculate the ultra-violet divergences in the case when the plasma sheet is slightly curved. The divergent terms are expressed in terms of surface integrals of corresponding invariants.

  10. Carrier Rexlaxation Time Divergence in Single and Double Layer Cuprates.

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M.; Rast, S.; Onellion, M.; Demsar, J.; Taylor, A. J.; Glinka, Y.; Tolk, N. H.; Ren, Y. H.; Lupke, G.; Klimov, A.; Sobolewski, R.; Xu, Y.; Si, Weidong; Zeng, X. H.; Soukiassian, A.; Xi, X. X.; Abrecht, M.; Ariosa, D.; Pavuna, D.; Drapf, A.; Manzke, R.; Printz, J. O.; Williamsen, M. S.; Downum, K. E.; Guptasarma, P.

    2003-06-20

    We report the transient optical pump-probe reflectivity measurements on single and double layer cuprate single crystals and thin films of ten different stoichiometries. We find that with sufficiently low fluence the relaxation time (tau [sub R] of all samples exhibits a power law divergence with temperature (T): tau [sub R] [proportional to] T[sup -3 [plus or minus] 0.5]. Further, the divergence has an onset temperature above the superconducting transition temperature for all superconducting samples. Possible causes of this divergence are discussed.

  11. Metric Divergence Measures and Information Value in Credit Scoring

    Directory of Open Access Journals (Sweden)

    Guoping Zeng

    2013-01-01

    Full Text Available Recently, a series of divergence measures have emerged from information theory and statistics and numerous inequalities have been established among them. However, none of them are a metric in topology. In this paper, we propose a class of metric divergence measures, namely, , and study their mathematical properties. We then study an important divergence measure widely used in credit scoring, called information value. In particular, we explore the mathematical reasoning of weight of evidence and suggest a better alternative to weight of evidence. Finally, we propose using as alternatives to information value to overcome its disadvantages.

  12. Functional Promiscuity of Two Divergent Paralogs of Type III Plant Polyketide Synthases.

    Science.gov (United States)

    Pandith, Shahzad A; Dhar, Niha; Rana, Satiander; Bhat, Wajid Waheed; Kushwaha, Manoj; Gupta, Ajai P; Shah, Manzoor A; Vishwakarma, Ram; Lattoo, Surrinder K

    2016-08-01

    Plants effectively defend themselves against biotic and abiotic stresses by synthesizing diverse secondary metabolites, including health-protective flavonoids. These display incredible chemical diversity and ubiquitous occurrence and confer impeccable biological and agricultural applications. Chalcone synthase (CHS), a type III plant polyketide synthase, is critical for flavonoid biosynthesis. It catalyzes acyl-coenzyme A thioesters to synthesize naringenin chalcone through a polyketidic intermediate. The functional divergence among the evolutionarily generated members of a gene family is pivotal in driving the chemical diversity. Against this backdrop, this study was aimed to functionally characterize members of the CHS gene family from Rheum emodi, an endangered and endemic high-altitude medicinal herb of northwestern Himalayas. Two full-length cDNAs (1,179 bp each), ReCHS1 and ReCHS2, encoding unique paralogs were isolated and characterized. Heterologous expression and purification in Escherichia coli, bottom-up proteomic characterization, high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry analysis, and enzyme kinetic studies using five different substrates confirmed their catalytic potential. Phylogenetic analysis revealed the existence of higher synonymous mutations in the intronless divergents of ReCHS. ReCHS2 displayed significant enzymatic efficiency (Vmax/Km) with different substrates. There were significant spatial and altitudinal variations in messenger RNA transcript levels of ReCHSs correlating positively with metabolite accumulation. Furthermore, the elicitations in the form of methyl jasmonate, salicylic acid, ultraviolet B light, and wounding, chosen on the basis of identified cis-regulatory promoter elements, presented considerable differences in the transcript profiles of ReCHSs. Taken together, our results demonstrate differential propensities of CHS paralogs in terms of the accumulation of flavonoids and

  13. The Role of Colonic Bacteria in the Metabolism of the Natural Isoflavone Daidzin to Equol

    OpenAIRE

    Fatemeh Rafii

    2015-01-01

    Isoflavones are found in leguminous plants, especially soybeans. They have a structural similarity to natural estrogens, which enables them to bind to estrogen receptors and elicit biological activities similar to natural estrogens. They have been suggested to be beneficial for the prevention and therapy of hormone-dependent diseases. After soy products are consumed, the bacteria of the intestinal microflora metabolize isoflavones to metabolites with altered absorption, bioavailability, and e...

  14. Global Association between Thermophilicity and Vancomycin Susceptibility in Bacteria.

    Science.gov (United States)

    Roy, Chayan; Alam, Masrure; Mandal, Subhrangshu; Haldar, Prabir K; Bhattacharya, Sabyasachi; Mukherjee, Trinetra; Roy, Rimi; Rameez, Moidu J; Misra, Anup K; Chakraborty, Ranadhir; Nanda, Ashish K; Mukhopadhyay, Subhra K; Ghosh, Wriddhiman

    2016-01-01

    Exploration of the aquatic microbiota of several circum-neutral (6.0-8.5 pH) mid-temperature (55-85°C) springs revealed rich diversities of phylogenetic relatives of mesophilic bacteria, which surpassed the diversity of the truly-thermophilic taxa. To gain insight into the potentially-thermophilic adaptations of the phylogenetic relatives of Gram-negative mesophilic bacteria detected in culture-independent investigations we attempted pure-culture isolation by supplementing the enrichment media with 50 μg ml(-1) vancomycin. Surprisingly, this Gram-positive-specific antibiotic eliminated the entire culturable-diversity of chemoorganotrophic and sulfur-chemolithotrophic bacteria present in the tested hot water inocula. Moreover, it also killed all the Gram-negative hot-spring isolates that were obtained in vancomycin-free media. Concurrent literature search for the description of Gram-negative thermophilic bacteria revealed that at least 16 of them were reportedly vancomycin-susceptible. While these data suggested that vancomycin-susceptibility could be a global trait of thermophilic bacteria (irrespective of their taxonomy, biogeography and Gram-character), MALDI Mass Spectroscopy of the peptidoglycans of a few Gram-negative thermophilic bacteria revealed that tandem alanines were present in the fourth and fifth positions of their muropeptide precursors (MPPs). Subsequent phylogenetic analyses revealed a close affinity between the D-alanine-D-alanine ligases (Ddl) of taxonomically-diverse Gram-negative thermophiles and the thermostable Ddl protein of Thermotoga maritima, which is well-known for its high specificity for alanine over other amino acids. The Ddl tree further illustrated a divergence between the homologs of Gram-negative thermophiles and mesophiles, which broadly coincided with vancomycin-susceptibility and vancomycin-resistance respectively. It was thus hypothesized that thermophilic Ddls have been evolutionarily selected to favor a D-ala-D-ala bonding

  15. Global association between thermophilicity and vancomycin susceptibility in bacteria

    Directory of Open Access Journals (Sweden)

    Chayan eRoy

    2016-03-01

    Full Text Available Exploration of the aquatic microbiota of several circum-neutral (6.0-8.5 pH mid-temperature (55-85 OC springs revealed rich diversities of phylogenetic relatives of mesophilic bacteria, which surpassed the diversity of the truly-thermophilic taxa. To gain insight into the potentially-thermophilic adaptations of the phylogenetic relatives of Gram-negative mesophilic bacteria detected in culture-independent investigations we attempted pure-culture isolation by supplementing the enrichment media with 50 µg ml-1 vancomycin. Surprisingly, this Gram-positive-specific antibiotic eliminated the entire culturable-diversity of chemoorganotrophic and sulfur-chemolithotrophic bacteria present in the tested hot water inocula. Moreover, it also killed all the Gram-negative hot-spring isolates that were obtained in vancomycin-free media. Concurrent literature search for the description of Gram-negative thermophilic bacteria revealed that at least 16 of them were reportedly vancomycin-susceptible. While these data suggested that vancomycin-susceptibility could be a global trait of thermophilic bacteria (irrespective of their taxonomy, biogeography and Gram-character, MALDI Mass Spectroscopy of the peptidoglycans of a few Gram-negative thermophilic bacteria revealed that tandem alanines were present in the fourth and fifth positions of their muropeptide precursors (MPPs. Subsequent phylogenetic analyses revealed a close affinity between the D-alanine-D-alanine ligases (Ddl of taxonomically-diverse Gram-negative thermophiles and the thermostable Ddl protein of Thermotoga maritima, which is well-known for its high specificity for alanine over other amino acids. The Ddl tree further illustrated a divergence between the homologs of Gram-negative thermophiles and mesophiles, which broadly coincided with vancomycin-susceptibility and vancomycin-resistance respectively. It was thus hypothesized that thermophilic Ddls have been evolutionarily selected to favor a D

  16. Role of mantle flow in Nubia-Somalia plate divergence

    Science.gov (United States)

    Stamps, D. S.; Iaffaldano, G.; Calais, E.

    2015-01-01

    Present-day continental extension along the East African Rift System (EARS) has often been attributed to diverging sublithospheric mantle flow associated with the African Superplume. This implies a degree of viscous coupling between mantle and lithosphere that remains poorly constrained. Recent advances in estimating present-day opening rates along the EARS from geodesy offer an opportunity to address this issue with geodynamic modeling of the mantle-lithosphere system. Here we use numerical models of the global mantle-plates coupled system to test the role of present-day mantle flow in Nubia-Somalia plate divergence across the EARS. The scenario yielding the best fit to geodetic observations is one where torques associated with gradients of gravitational potential energy stored in the African highlands are resisted by weak continental faults and mantle basal drag. These results suggest that shear tractions from diverging mantle flow play a minor role in present-day Nubia-Somalia divergence.

  17. Multiple solutions for possibly degenerate equations in divergence form

    Directory of Open Access Journals (Sweden)

    Andrea Pinamonti

    2016-08-01

    Full Text Available Via variational methods, we establish the existence of at least two distinct weak solutions for the Dirichlet problem associated to a possibly degenerate equation in divergence form.

  18. Scalar Field Quantization Without Divergences In All Spacetime Dimensions

    CERN Document Server

    Klauder, John R

    2011-01-01

    Covariant, self-interacting scalar quantum field theories admit solutions for low enough spacetime dimensions, but when additional divergences appear in higher dimensions, the traditional approach leads to results, such as triviality, that are less than satisfactory. Guided by idealized but soluble nonrenormalizable models, a nontraditional proposal for the quantization of covariant scalar field theories is advanced, which achieves a term-by-term, divergence-free, perturbation analysis of interacting models expanded about a suitable pseudofree theory, which differs from a free theory by an O(\\hbar^2) counterterm. These positive features are secured within a functional integral formulation by a local, nonclassical, counterterm that effectively transforms parameter changes in the action from generating mutually singular measures, which are the basis for divergences, to equivalent measures, thereby removing all divergences. The use of an alternative model about which to perturb is already supported by properties...

  19. Eliciting Parents' Individual Requirements for an Inclusive Digital School System.

    Science.gov (United States)

    Eftring, Håkan; Rassmus-Gröhn, Kirsten; Hedvall, Per-Olof

    2016-01-01

    Parents often have a busy time sorting out their life puzzles, including getting information about their children's activities in school. More and more communication between teachers and parents take place via digital school systems. It can be hard for parents to find the information they are looking for and the teacher decides when information is sent and what communication method to use. All parents, but especially parents with disabilities, might have individual preferences on how to receive information and how to adapt meetings at school. In this paper we present a project where we involved parents and teachers in focus groups, an idea workshop and iterative user trials of a digital prototype. The goal was to elicit parents' individual requirements for an inclusive digital school system, where they can store their individual preferences about how and when to receive information from school and what requirements they have on meetings at school. Preliminary results show that we managed to create open and focused discussions among parents and teachers. The parents reacted very positively on an onboarding page with the possibility to quickly and easily enter preferences after their first log in, but more work needs to be done on how preferences are categorized on the onboarding page. Finally, parents need to get clear feedback from teachers and school when they have entered or updated preferences, so they can trust that their preferences will be met. PMID:27534306

  20. Multiple Membrane Interactions and Versatile Vesicle Deformations Elicited by Melittin

    Directory of Open Access Journals (Sweden)

    Kingo Takiguchi

    2013-04-01

    Full Text Available Melittin induces various reactions in membranes and has been widely studied as a model for membrane-interacting peptide; however, the mechanism whereby melittin elicits its effects remains unclear. Here, we observed melittin-induced changes in individual giant liposomes using direct real-time imaging by dark-field optical microscopy, and the mechanisms involved were correlated with results obtained using circular dichroism, cosedimentation, fluorescence quenching of tryptophan residues, and electron microscopy. Depending on the concentration of negatively charged phospholipids in the membrane and the molecular ratio between lipid and melittin, melittin induced the “increasing membrane area”, “phased shrinkage”, or “solubilization” of liposomes. In phased shrinkage, liposomes formed small particles on their surface and rapidly decreased in size. Under conditions in which the increasing membrane area, phased shrinkage, or solubilization were mainly observed, the secondary structure of melittin was primarily estimated as an α-helix, β-like, or disordered structure, respectively. When the increasing membrane area or phased shrinkage occurred, almost all melittin was bound to the membranes and reached more hydrophobic regions of the membranes than when solubilization occurred. These results indicate that the various effects of melittin result from its ability to adopt various structures and membrane-binding states depending on the conditions.

  1. Affective monitoring: A generic mechanism for affect elicitation

    Directory of Open Access Journals (Sweden)

    Hans ePhaf

    2012-03-01

    Full Text Available In this paper we sketch a new framework for affect elicitation, which is based on previous evolutionary and connectionist modeling and experimental work from our group. Affective monitoring is considered a local match-mismatch process within a module of the neural network. Negative affect is raised instantly by mismatches, incongruency, disfluency, novelty, incoherence, and dissonance, whereas positive affect follows from matches, congruency, fluency, familiarity, coherence, and resonance, at least when an initial mismatch can be solved quickly. Affective monitoring is considered an evolutionary-early conflict and change detection process operating at the same level as, for instance, attentional selection. It runs in parallel and imparts affective flavour to emotional behavior systems, which involve evolutionary-prepared stimuli and action tendencies related to for instance defensive, exploratory, attachment, or appetitive behavior. Positive affect is represented in the networks by high-frequency oscillations, presumably in the gamma band. Negative affect corresponds to more incoherent lower-frequency oscillations, presumably in the theta band. For affect to become conscious, large-scale synchronization of the oscillations over the network and the construction of emotional experiences are required. These constructions involve perceptions of bodily states and action tendencies, but also appraisals as well as efforts to regulate the emotion. Importantly, affective monitoring accompanies every kind of information processing, but conscious emotions, which result from the later integration of affect in a cognitive context, are much rarer events.

  2. Cancer-induced immunosuppression: IL-18-elicited immunoablative NK cells.

    Science.gov (United States)

    Terme, Magali; Ullrich, Evelyn; Aymeric, Laetitia; Meinhardt, Kathrin; Coudert, Jérôme D; Desbois, Mélanie; Ghiringhelli, François; Viaud, Sophie; Ryffel, Bernard; Yagita, Hideo; Chen, Lieping; Mécheri, Salaheddine; Kaplanski, Gilles; Prévost-Blondel, Armelle; Kato, Masashi; Schultze, Joachim L; Tartour, Eric; Kroemer, Guido; Degli-Esposti, Mariapia; Chaput, Nathalie; Zitvogel, Laurence

    2012-06-01

    During cancer development, a number of regulatory cell subsets and immunosuppressive cytokines subvert adaptive immune responses. Although it has been shown that tumor-derived interleukin (IL)-18 participates in the PD-1-dependent tumor progression in NK cell-controlled cancers, the mechanistic cues underlying this immunosuppression remain unknown. Here, we show that IL-18 converts a subset of Kit(-) (CD11b(-)) into Kit(+) natural killer (NK) cells, which accumulate in all lymphoid organs of tumor bearers and mediate immunoablative functions. Kit(+) NK cells overexpressed B7-H1/PD-L1, a ligand for PD-1. The adoptive transfer of Kit(+) NK cells promoted tumor growth in two pulmonary metastases tumor models and significantly reduced the dendritic and NK cell pools residing in lymphoid organs in a B7-H1-dependent manner. Neutralization of IL-18 by RNA interference in tumors or systemically by IL-18-binding protein dramatically reduced the accumulation of Kit(+)CD11b(-) NK cells in tumor bearers. Together, our findings show that IL-18 produced by tumor cells elicits Kit(+)CD11b(-) NK cells endowed with B7-H1-dependent immunoablative functions in mice. PMID:22427351

  3. Dreamed movement elicits activation in the sensorimotor cortex.

    Science.gov (United States)

    Dresler, Martin; Koch, Stefan P; Wehrle, Renate; Spoormaker, Victor I; Holsboer, Florian; Steiger, Axel; Sämann, Philipp G; Obrig, Hellmuth; Czisch, Michael

    2011-11-01

    Since the discovery of the close association between rapid eye movement (REM) sleep and dreaming, much effort has been devoted to link physiological signatures of REM sleep to the contents of associated dreams [1-4]. Due to the impossibility of experimentally controlling spontaneous dream activity, however, a direct demonstration of dream contents by neuroimaging methods is lacking. By combining brain imaging with polysomnography and exploiting the state of "lucid dreaming," we show here that a predefined motor task performed during dreaming elicits neuronal activation in the sensorimotor cortex. In lucid dreams, the subject is aware of the dreaming state and capable of performing predefined actions while all standard polysomnographic criteria of REM sleep are fulfilled [5, 6]. Using eye signals as temporal markers, neural activity measured by functional magnetic resonance imaging (fMRI) and near-infrared spectroscopy (NIRS) was related to dreamed hand movements during lucid REM sleep. Though preliminary, we provide first evidence that specific contents of REM-associated dreaming can be visualized by neuroimaging.

  4. Mesencephalic stimulation elicits inhibition of phrenic nerve activity in cat.

    Science.gov (United States)

    Gallman, E A; Lawing, W L; Millhorn, D E

    1991-05-01

    1. Previous work from this laboratory has indicated that the mesencephalon is the anatomical substrate for a mechanism capable of inhibiting central respiratory drive in glomectomized cats for periods of up to 1 h or more following brief exposure to systemic hypoxia; phrenic nerve activity was used as an index of central respiratory drive. 2. The present study was undertaken to further localize the region responsible for the observed post-hypoxic inhibition of respiratory drive. We studied the phrenic nerve response to stimulations of the mesencephalon in anaesthetized, paralysed peripherally chemo-denervated cats with end-expired PCO2 and body temperature servo-controlled. 3. Stimulations of two types were employed. Electrical stimulation allowed rapid determination of sites from which phrenic inhibition could be elicited. Microinjections of excitatory amino acids were used subsequently in order to confine excitation to neuronal cell bodies and not axons of passage. 4. Stimulation of discrete regions of the ventromedial aspect of the mesencephalon in the vicinity of the red nucleus produced substantial inhibition of phrenic activity which lasted up to 45 min. Stimulation of other areas of the mesencephalon either produced no phrenic inhibition or resulted in a slight stimulation of phrenic activity. 5. The results are discussed in the context of the central respiratory response to hypoxia. PMID:1676420

  5. Immunological responses elicited by different infection regimes with Strongyloides ratti.

    Directory of Open Access Journals (Sweden)

    Steve Paterson

    Full Text Available Nematode infections are a ubiquitous feature of vertebrate life. In nature, such nematode infections are acquired by continued exposure to infective stages over a prolonged period of time. By contrast, experimental laboratory infections are typically induced by the administration of a single (and often large dose of infective stages. Previous work has shown that the size of an infection dose can have significant effects on anti-nematode immune responses. Here we investigated the effect of different infection regimes of Strongyloides ratti, comparing single and repeated dose infections, on the host immune response that was elicited. We considered and compared infections of the same size, but administered in different ways. We considered infection size in two ways: the maximum dose of worms administered and the cumulative worm exposure time. We found that both infection regimes resulted in Th2-type immune response, characterised by IL4 and IL13 produced by S. ratti stimulated mesenteric lymph node cells, anti-S. ratti IgG(1 and intestinal rat mast cell protease II (RMCPII production. We observed some small quantitative immunological differences between different infection regimes, in which the concentration of IL4, IL13, anti-S. ratti IgG(1 and IgG(2a and RMCPII were affected. However, these differences were quantitatively relatively modest compared with the temporal dynamics of the anti-S. ratti immune response as a whole.

  6. Point of view filming and the elicitation interview.

    Science.gov (United States)

    Skinner, Jonathan; Gormley, Gerard J

    2016-08-01

    Face-to-face interviews are a fundamental research tool in qualitative research. Whilst this form of data collection can provide many valuable insights, it can often fall short of providing a complete picture of a research subject's experiences. Point of view (PoV) interviewing is an elicitation technique used in the social sciences as a means of enriching data obtained from research interviews. Recording research subjects' first person perspectives, for example by wearing digital video glasses, can afford deeper insights into their experiences. PoV interviewing can promote making visible the unverbalizable and does not rely as much on memory as the traditional interview. The use of such relatively inexpensive technology is gaining interest in health profession educational research and pedagogy, such as dynamic simulation-based learning and research activities. In this interview, Dr Gerry Gormley (a medical education researcher) talks to Dr Jonathan Skinner (an anthropologist with an interest in PoV interviewing), exploring some of the many crossover implications with PoV interviewing for medical education research and practice. PMID:27438056

  7. Point of view filming and the elicitation interview.

    Science.gov (United States)

    Skinner, Jonathan; Gormley, Gerard J

    2016-08-01

    Face-to-face interviews are a fundamental research tool in qualitative research. Whilst this form of data collection can provide many valuable insights, it can often fall short of providing a complete picture of a research subject's experiences. Point of view (PoV) interviewing is an elicitation technique used in the social sciences as a means of enriching data obtained from research interviews. Recording research subjects' first person perspectives, for example by wearing digital video glasses, can afford deeper insights into their experiences. PoV interviewing can promote making visible the unverbalizable and does not rely as much on memory as the traditional interview. The use of such relatively inexpensive technology is gaining interest in health profession educational research and pedagogy, such as dynamic simulation-based learning and research activities. In this interview, Dr Gerry Gormley (a medical education researcher) talks to Dr Jonathan Skinner (an anthropologist with an interest in PoV interviewing), exploring some of the many crossover implications with PoV interviewing for medical education research and practice.

  8. Naturalistic Enactment to Elicit and Recognize Caregiver State Anxiety.

    Science.gov (United States)

    Miranda, Darien; Favela, Jesus; Ibarra, Catalina; Cruz, Netzahualcoyotl

    2016-09-01

    Caring for people with dementia imposes significant stress on family members and caregivers. Often, these informal caregivers have no coping strategy to deal with these behaviors. Anxiety and stress episodes are often triggered by problematic behaviors exhibited by the person who suffers from dementia. Detecting these behaviors could help them in dealing with them and reduce caregiver burden. However, work on anxiety detection using physiological signals has mostly been done under controlled conditions. In this paper we describe an experiment aimed at inducing anxiety among caregivers of people with dementia under naturalistic conditions. We report an experiment, using the naturalistic enactment technique, in which 10 subjects were asked to care for an older adult who acts as if she experiences dementia. We record physiological signals from the participants (GSR, HR, EEG) during the sessions that lasted for approximately 30 min. We explain how we obtained ground truth from self-report and observation data. We conducted two different tests using the Support Vector Machine technique. We obtained an average precision of 77.8 % and 38.1 % recall when classifying two different possible states: "Anxious" and "Not anxious". Analysis of the data provides evidence that the experiment elicits state anxiety and that it can be detected using wearable sensors. Furthermore, if episodes of problematic behaviors can also be detected, the recognition of anxiety in the caregiver can be improved, leading to the enactment of appropriate interventions to help caregivers cope with anxiety episodes. PMID:27443338

  9. Dreamed movement elicits activation in the sensorimotor cortex.

    Science.gov (United States)

    Dresler, Martin; Koch, Stefan P; Wehrle, Renate; Spoormaker, Victor I; Holsboer, Florian; Steiger, Axel; Sämann, Philipp G; Obrig, Hellmuth; Czisch, Michael

    2011-11-01

    Since the discovery of the close association between rapid eye movement (REM) sleep and dreaming, much effort has been devoted to link physiological signatures of REM sleep to the contents of associated dreams [1-4]. Due to the impossibility of experimentally controlling spontaneous dream activity, however, a direct demonstration of dream contents by neuroimaging methods is lacking. By combining brain imaging with polysomnography and exploiting the state of "lucid dreaming," we show here that a predefined motor task performed during dreaming elicits neuronal activation in the sensorimotor cortex. In lucid dreams, the subject is aware of the dreaming state and capable of performing predefined actions while all standard polysomnographic criteria of REM sleep are fulfilled [5, 6]. Using eye signals as temporal markers, neural activity measured by functional magnetic resonance imaging (fMRI) and near-infrared spectroscopy (NIRS) was related to dreamed hand movements during lucid REM sleep. Though preliminary, we provide first evidence that specific contents of REM-associated dreaming can be visualized by neuroimaging. PMID:22036177

  10. Corporate governance of financial intermediaries: convergence and divergence

    OpenAIRE

    Nedelchev, Miroslav

    2012-01-01

    The paper reviews the corporate governance from his evolution point of view. The used perspective is a discussion between convergence and divergence in corporate governance of financial intermediaries. The discussion is core for researches in scientific and implementation papers for last fifty years. Based on “principal-agent” model the paper illustrates both the dynamics of corporate governance and contemporary points of view for convergence and divergence of systems and practices. Th...

  11. Varying the Divergence of Multiple Parallel Laser Beams

    Science.gov (United States)

    Kovalik, Joseph M.; Wright, Malcolm W.

    2008-01-01

    A provision for controlled variation of the divergence of a laser beam or of multiple parallel laser beams has been incorporated into the design of a conceptual free-space optical-communication station from which the transmitted laser beam(s) would be launched via a telescope. The original purpose to be served by this provision was to enable optimization, under various atmospheric optical conditions, of the divergence of a laser beam or beams transmitted from a ground station to a spacecraft.

  12. Numerical Optimization of converging diverging miniature cavitating nozzles

    Science.gov (United States)

    Chavan, Kanchan; Bhingole, B.; Raut, J.; Pandit, A. B.

    2015-12-01

    The work focuses on the numerical optimization of converging diverging cavitating nozzles through nozzle dimensions and wall shape. The objective is to develop design rules for the geometry of cavitating nozzles for desired end-use. Two main aspects of nozzle design which affects the cavitation have been studied i.e. end dimensions of the geometry (i.e. angle and/or curvature of the inlet, outlet and the throat and the lengths of the converging and diverging sections) and wall curvatures(concave or convex). Angle of convergence at the inlet was found to control the cavity growth whereas angle of divergence of the exit controls the collapse of cavity. CFD simulations were carried out for the straight line converging and diverging sections by varying converging and diverging angles to study its effect on the collapse pressure generated by the cavity. Optimized geometry configurations were obtained on the basis of maximum Cavitational Efficacy Ratio (CER)i.e. cavity collapse pressure generated for a given permanent pressure drop across the system. With increasing capabilities in machining and fabrication, it is possible to exploit the effect of wall curvature to create nozzles with further increase in the CER. Effect of wall curvature has been studied for the straight, concave and convex shapes. Curvature has been varied and effect of concave and convex wall curvatures vis-à-vis straight walls studied for fixed converging and diverging angles.It is concluded that concave converging-diverging nozzles with converging angle of 20° and diverging angle of 5° with the radius of curvature 0.03 m and 0.1530 m respectively gives maximum CER. Preliminary experiments using optimized geometry are indicating similar trends and are currently being carried out. Refinements of the CFD technique using two phase flow simulations are planned.

  13. Dimensional regularization and infrared divergences in quantum electrodynamics

    International Nuclear Information System (INIS)

    Dimensional continuation was devised as a powerful regularization method for ultraviolet divergences in quantum field theories. Recently it was clear, at least for quantum electrodynamics, that such a method could be employed for factorizing out infrared divergences from the on-shell S-matrix elements. This provides a renormalization scheme on the electron mass-shell without using a gauge violating ''photon mass''. (author)

  14. Metric redefinition and UV divergences in quantum Einstein gravity

    Directory of Open Access Journals (Sweden)

    Sergey N. Solodukhin

    2016-03-01

    Full Text Available I formulate several statements demonstrating that the local metric redefinition can be used to reduce the UV divergences present in the quantum action for the Einstein gravity in d=4 dimensions. In its most general form, the proposal is that any UV divergences in the quantum action can be removed by an appropriate field re-definition and a renormalization of cosmological constant.

  15. Average Contrastive Divergence for Training Restricted Boltzmann Machines

    OpenAIRE

    Xuesi Ma; Xiaojie Wang

    2016-01-01

    This paper studies contrastive divergence (CD) learning algorithm and proposes a new algorithm for training restricted Boltzmann machines (RBMs). We derive that CD is a biased estimator of the log-likelihood gradient method and make an analysis of the bias. Meanwhile, we propose a new learning algorithm called average contrastive divergence (ACD) for training RBMs. It is an improved CD algorithm, and it is different from the traditional CD algorithm. Finally, we obtain some experimental resul...

  16. Policy Convergence and Divergence in Scotland under Devolution

    OpenAIRE

    Keating, Michael

    2005-01-01

    The scope for divergence of public policy between Scotland and the rest of the UK is constrained by institutional, political and contextual factors. The policy capacity of the Scottish Executive is limited but increasing. Distinct Scottish policy communities are emerging, but there is variation by sector. There are important divergences in the organization and delivery of public services. Scotland is more committed than England to the traditional public sector model, emphasizing egalitarianis...

  17. Divergences in the Euro Area: a Cause for Concern?

    OpenAIRE

    Björkstén, Nils; Syrjänen, Miika

    1999-01-01

    Evidence suggests that after a period of convergence in the early and mid-1990s, the euro area economies may have started diverging. As a consequence, the common monetary policy could become well-suited for a number of countries. This paper studies the extent and severity of the recent divergences, and discusses the capacity of exposed countries to compensate for nationally suboptimal monetary conditions through other policy channels. As a step toward developing an analytical framework for mo...

  18. Biogeography of thermophilic phototrophic bacteria belonging to Roseiflexus genus.

    Science.gov (United States)

    Gaisin, Vasil A; Grouzdev, Denis S; Namsaraev, Zorigto B; Sukhacheva, Marina V; Gorlenko, Vladimir M; Kuznetsov, Boris B

    2016-03-01

    Isolated environments such as hot springs are particularly interesting for studying the microbial biogeography. These environments create an 'island effect' leading to genetic divergence. We studied the phylogeographic pattern of thermophilic anoxygenic phototrophic bacteria, belonging to the Roseiflexus genus. The main characteristic of the observed pattern was geographic and geochronologic fidelity to the hot springs within Circum-Pacific and Alpine-Himalayan-Indonesian orogenic belts. Mantel test revealed a correlation between genetic divergence and geographic distance among the phylotypes. Cluster analysis revealed a regional differentiation of the global phylogenetic pattern. The phylogeographic pattern is in correlation with geochronologic events during the break up of Pangaea that led to the modern configuration of continents. To our knowledge this is the first geochronological scenario of intercontinental prokaryotic taxon divergence. The existence of the modern phylogeographic pattern contradicts with the existence of the ancient evolutionary history of the Roseiflexus group proposed on the basis of its deep-branching phylogenetic position. These facts indicate that evolutionary rates in Roseiflexus varied over a wide range.

  19. Biogeography of thermophilic phototrophic bacteria belonging to Roseiflexus genus.

    Science.gov (United States)

    Gaisin, Vasil A; Grouzdev, Denis S; Namsaraev, Zorigto B; Sukhacheva, Marina V; Gorlenko, Vladimir M; Kuznetsov, Boris B

    2016-03-01

    Isolated environments such as hot springs are particularly interesting for studying the microbial biogeography. These environments create an 'island effect' leading to genetic divergence. We studied the phylogeographic pattern of thermophilic anoxygenic phototrophic bacteria, belonging to the Roseiflexus genus. The main characteristic of the observed pattern was geographic and geochronologic fidelity to the hot springs within Circum-Pacific and Alpine-Himalayan-Indonesian orogenic belts. Mantel test revealed a correlation between genetic divergence and geographic distance among the phylotypes. Cluster analysis revealed a regional differentiation of the global phylogenetic pattern. The phylogeographic pattern is in correlation with geochronologic events during the break up of Pangaea that led to the modern configuration of continents. To our knowledge this is the first geochronological scenario of intercontinental prokaryotic taxon divergence. The existence of the modern phylogeographic pattern contradicts with the existence of the ancient evolutionary history of the Roseiflexus group proposed on the basis of its deep-branching phylogenetic position. These facts indicate that evolutionary rates in Roseiflexus varied over a wide range. PMID:26826142

  20. LEA/LANSAD : Convergences/Divergences LEA/LANSAD : Convergences/Divergences

    Directory of Open Access Journals (Sweden)

    Elizabeth Crosnier

    2011-08-01

    Full Text Available Les secteurs LEA (Langues Étrangères Appliquées et LANSAD (LANgues pour Spécialistes d'Autres Disciplines ont pour même objectif de développer des compétences communicationnelles. Même si leurs politiques et leurs méthodes d’enseignement divergent au travers de pratiques et de critères différents, ils sont confrontés à des obstacles similaires qui entravent leur mission. Au vu de ces convergences et de ces divergences, nous proposons de nous intéresser à la motivation des étudiants et des enseignants dans la mesure où elle concerne les deux formations. Il s’agit de s’interroger sur les facteurs qui interviennent comme éléments déclencheurs. Nous avons choisi notamment les programmes, l’évaluation de l’erreur ainsi que les besoins et les perspectives de carrière. Nous pensons qu’une recherche/action commune fournira aux enseignants et aux apprenants LEA et LANSAD un apport particulièrement précieux. Nous avons réellement besoin de données fiables résultant d’enquêtes d’envergure afin de mettre fin à la confusion qui prévaut en matière de prises de décisions et d’évaluation. Un travail effectué conjointement permettrait également d’obtenir davantage de reconnaissance de la part de nos institutions.LEA (Applied Languages and LANSAD (Languages for Students of Other Disciplines curricula aim at providing students with English communication skills. Even if they adopt diverging teaching policies and approaches by using different criteria and training practices, they have to face similar obstacles to meeting their goals. Their similarities and discrepancies suggest that student and teacher motivation can be regarded as a major concern for the two communities. The question is to investigate some triggering factors, namely the syllabi, error assessment, and career needs and prospects. To this end, joint action research is likely to be most valuable to LEA and LANSAD teachers and learners alike. We do

  1. Inference by Minimizing Size, Divergence, or their Sum

    CERN Document Server

    Riedel, Sebastian; McCallum, Andrew

    2012-01-01

    We speed up marginal inference by ignoring factors that do not significantly contribute to overall accuracy. In order to pick a suitable subset of factors to ignore, we propose three schemes: minimizing the number of model factors under a bound on the KL divergence between pruned and full models; minimizing the KL divergence under a bound on factor count; and minimizing the weighted sum of KL divergence and factor count. All three problems are solved using an approximation of the KL divergence than can be calculated in terms of marginals computed on a simple seed graph. Applied to synthetic image denoising and to three different types of NLP parsing models, this technique performs marginal inference up to 11 times faster than loopy BP, with graph sizes reduced up to 98%-at comparable error in marginals and parsing accuracy. We also show that minimizing the weighted sum of divergence and size is substantially faster than minimizing either of the other objectives based on the approximation to divergence present...

  2. New divergence measures and their application in multimodal image registration

    Science.gov (United States)

    Shi, Yonggang

    2005-07-01

    Information theoretic divergence measures, especially mutual information, have been widely employed in multimodal image registration. Mutual information is the Kullback-Leibler divergence between the joint distribution of the two images' grey values and the product of their marginal distributions. Apart from these metrics, however, there are other measures which could be considered for the task of image registration. In this paper, the connections are investigated between mutual information, Kullback-Leibler divergence and Shannon inequality. In information theory, Inequalities connect information divergence with other measures of discrimination between probability distributions. Based on these connections and inequality theory, a novel definition of generalized divergence measures is proposed. Three classical inequalities, arithmetic-geometric inequality, Cauchy-Schwarz inequality, and Minkowski inequality are analyzed, hence, corresponding divergence measures are given, which are used for registration measures. The measures are applied to rigid registration of multimodal medical images. This paper compares the performance of mutual information with the proposed registration measures. Simulation results show that the new measures are effective and efficient, and may be more robust to noise, and furthermore, some of them need less execution time than mutual information.

  3. MHC adaptive divergence between closely related and sympatric African cichlids.

    Directory of Open Access Journals (Sweden)

    Jonatan Blais

    Full Text Available BACKGROUND: The haplochromine cichlid species assemblages of Lake Malawi and Victoria represent some of the most important study systems in evolutionary biology. Identifying adaptive divergence between closely-related species can provide important insights into the processes that may have contributed to these spectacular radiations. Here, we studied a pair of sympatric Lake Malawi species, Pseudotropheus fainzilberi and P. emmiltos, whose reproductive isolation depends on olfactory communication. We tested the hypothesis that these species have undergone divergent selection at MHC class II genes, which are known to contribute to olfactory-based mate choice in other taxa. METHODOLOGY/PRINCIPAL FINDINGS: Divergent selection on functional alleles was inferred from the higher genetic divergence at putative antigen binding sites (ABS amino acid sequences than at putatively neutrally evolving sites at intron 1, exon 2 synonymous sequences and exon 2 amino acid residues outside the putative ABS. In addition, sympatric populations of these fish species differed significantly in communities of eukaryotic parasites. CONCLUSIONS/SIGNIFICANCE: We propose that local host-parasite coevolutionary dynamics may have driven adaptive divergence in MHC alleles, influencing odor-mediated mate choice and leading to reproductive isolation. These results provide the first evidence for a novel mechanism of adaptive speciation and the first evidence of adaptive divergence at the MHC in closely related African cichlid fishes.

  4. Qualitative Evaluation of Divergent Thinking in Patients with Schizophrenia

    Directory of Open Access Journals (Sweden)

    Takahiro Nemoto

    2005-01-01

    Full Text Available Patients with schizophrenia show deficits across a broad spectrum of neurocognitive domains. In particular, deficits in verbal fluency are common. Verbal fluency tests are neuropsychological tests that assess frontal lobe function or executive function but also assess divergent thinking. However, few studies have considered the impairment of verbal fluency from the viewpoint of divergent thinking. To consider the structure of divergent thinking, not only verbal assessments but also non-verbal assessments are indispensable. We administered several fluency tests, the idea fluency test, the design fluency test, and word (letter and category fluency tests to 26 patients with schizophrenia and 26 healthy control subjects to evaluate divergent thinking in both groups and assessed their responses qualitatively. An acceptable minimal level of intelligence was maintained in the patient group. Although attention and executive functioning were relatively preserved in the subjects with schizophrenia, they demonstrated significant deficits in divergent thinking and had particular difficulty in producing ideas and designs requiring concept flexibility, a conversion of viewpoint, originality, or novelty. Research on deficits in divergent thinking in patients with schizophrenia may contribute to the development of cognitive and behavioral rehabilitation programs.

  5. Azospirillum genomes reveal transition of bacteria from aquatic to terrestrial environments.

    Directory of Open Access Journals (Sweden)

    Florence Wisniewski-Dyé

    2011-12-01

    Full Text Available Fossil records indicate that life appeared in marine environments ∼3.5 billion years ago (Gyr and transitioned to terrestrial ecosystems nearly 2.5 Gyr. Sequence analysis suggests that "hydrobacteria" and "terrabacteria" might have diverged as early as 3 Gyr. Bacteria of the genus Azospirillum are associated with roots of terrestrial plants; however, virtually all their close relatives are aquatic. We obtained genome sequences of two Azospirillum species and analyzed their gene origins. While most Azospirillum house-keeping genes have orthologs in its close aquatic relatives, this lineage has obtained nearly half of its genome from terrestrial organisms. The majority of genes encoding functions critical for association with plants are among horizontally transferred genes. Our results show that transition of some aquatic bacteria to terrestrial habitats occurred much later than the suggested initial divergence of hydro- and terrabacterial clades. The birth of the genus Azospirillum approximately coincided with the emergence of vascular plants on land.

  6. Nitrogen control in bacteria.

    Science.gov (United States)

    Merrick, M J; Edwards, R A

    1995-12-01

    Nitrogen metabolism in prokaryotes involves the coordinated expression of a large number of enzymes concerned with both utilization of extracellular nitrogen sources and intracellular biosynthesis of nitrogen-containing compounds. The control of this expression is determined by the availability of fixed nitrogen to the cell and is effected by complex regulatory networks involving regulation at both the transcriptional and posttranslational levels. While the most detailed studies to date have been carried out with enteric bacteria, there is a considerable body of evidence to show that the nitrogen regulation (ntr) systems described in the enterics extend to many other genera. Furthermore, as the range of bacteria in which the phenomenon of nitrogen control is examined is being extended, new regulatory mechanisms are also being discovered. In this review, we have attempted to summarize recent research in prokaryotic nitrogen control; to show the ubiquity of the ntr system, at least in gram-negative organisms; and to identify those areas and groups of organisms about which there is much still to learn. PMID:8531888

  7. Chemical communication in bacteria

    Science.gov (United States)

    Suravajhala, Srinivasa Sandeep; Saini, Deepak; Nott, Prabhu

    Luminescence in Vibrio fischeri is a model for quorum-sensing-gene-regulation in bacteria. We study luminescence response of V. fischeri to both internal and external cues at the single cell and population level. Experiments with ES114, a wild-type strain, and ainS mutant show that luminescence induction in cultures is not always proportional to cell-density and there is always a basal level of luminescence. At any given concentration of the exogenously added signals, C6-HSL and C8-HSL, luminescence per cell reaches a maximum during the exponential phase and decreases thereafter. We hypothesize that (1) C6-HSL production and LuxR activity are not proportional to cell-density, and (2) there is a shift in equilibrium from C6-HSL to C8-HSL during the later stages of growth of the culture. RT-PCR analysis of luxI and luxR shows that the expression of these genes is maximum corresponding to the highest level of luminescence. The shift in equilibrium is shown by studying competitive binding of C6-HSL and C8-HSL to LuxR. We argue that luminescence is a unicellular behaviour, and an intensive property like per cell luminescence is more important than gross luminescence of the population in understanding response of bacteria to chemical signalling. Funding from the Department of Science and Technology, India is acknowledged.

  8. Beneficial bacteria inhibit cachexia.

    Science.gov (United States)

    Varian, Bernard J; Goureshetti, Sravya; Poutahidis, Theofilos; Lakritz, Jessica R; Levkovich, Tatiana; Kwok, Caitlin; Teliousis, Konstantinos; Ibrahim, Yassin M; Mirabal, Sheyla; Erdman, Susan E

    2016-03-15

    Muscle wasting, known as cachexia, is a debilitating condition associated with chronic inflammation such as during cancer. Beneficial microbes have been shown to optimize systemic inflammatory tone during good health; however, interactions between microbes and host immunity in the context of cachexia are incompletely understood. Here we use mouse models to test roles for bacteria in muscle wasting syndromes. We find that feeding of a human commensal microbe, Lactobacillus reuteri, to mice is sufficient to lower systemic indices of inflammation and inhibit cachexia. Further, the microbial muscle-building phenomenon extends to normal aging as wild type animals exhibited increased growth hormone levels and up-regulation of transcription factor Forkhead Box N1 [FoxN1] associated with thymus gland retention and longevity. Interestingly, mice with a defective FoxN1 gene (athymic nude) fail to inhibit sarcopenia after L. reuteri therapy, indicating a FoxN1-mediated mechanism. In conclusion, symbiotic bacteria may serve to stimulate FoxN1 and thymic functions that regulate inflammation, offering possible alternatives for cachexia prevention and novel insights into roles for microbiota in mammalian ontogeny and phylogeny. PMID:26933816

  9. The time-dose-response relationship for elicitation of contact dermatitis in isoeugenol allergic individuals

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Johansen, Jeanne Duus; Bruze, M;

    2001-01-01

    The elicitation response in allergic contact dermatitis is dose dependent, but the time-concentration relationship for elicitation has not previously been described. In this study 27 isoeugenol-sensitive patients participated in serial dilution patch tests with isoeugenol and a double-blinded Rep...

  10. Dynamic Assessment of Elicited Imitation: A Case Analysis of an Advanced L2 English Speaker

    Science.gov (United States)

    van Compernolle, Rémi A.; Zhang, Haomin

    2014-01-01

    The focus of this paper is on the design, administration, and scoring of a dynamically administered elicited imitation test of L2 English morphology. Drawing on Vygotskian sociocultural psychology, particularly the concepts of zone of proximal development and dynamic assessment, we argue that support provided during the elicited imitation test…

  11. Stone Soup: Photo-Elicitation as a Learning Tool in the Food Geography Classroom

    Science.gov (United States)

    Kurtz, Hilda E.; Wood, Jason

    2014-01-01

    This paper showcases self-reflective and inclusive pedagogy using photo-elicitation in a food geography course assignment. The Stone Soup project positions students as both researchers and participant-subjects in a participant-driven photo-elicitation (PDPE) study of students' foodways. Student papers for this assignment demonstrate rich…

  12. Eliciting and communicating expert judgments: methodology and application to nuclear safety

    International Nuclear Information System (INIS)

    Expert judgment has always been used informally in the analysis of complex engineering problems. Increasingly, however, the use of expert judgment has been formalized by eliciting judgments in an explicit, documented and often quantitative way. In nuclear safety studies the need for formal elicitation of expert judgments arises because of the lack of data and experiences, the need to adapt model results to the specific circumstances of a plant, and the large uncertainties surrounding the events and quantities that characterize an accident sequence. The recognition of the need for a formal elicitation of expert judgments has led to one of the most extensive expert elicitation processes to date in the context of the NUREG 1150 study. About 30 safety issues were quantified using expert judgments about probabilities of various uncertain events and quantities, ranging from the failure of a check valve in the cooling system to the pressure built up due to hydrogen production to release fractions of various radionuclides. In total, some 1000 probability distributions were elicited from some 50 experts. This paper first motivates the use of formal expert elicitation in complex engineering studies and describes the methodology of formal expert elicitation. Subsequently, it describes the overall approach of NUREG 1150 and provides an example of the elicitation of the probability of a bypass failure in a pressurized water reactor. The paper ends by discussing some lessons learned, problems encountered and by providing some recommendations

  13. Identifying and Responding to Personal Stressors: Utilizing Photo Elicitation in Health Education Courses

    Science.gov (United States)

    Hunter, Theresa

    2014-01-01

    The "Photo Elicitation Project" teaching idea applies the techniques of photo elicitation to stress prevention and management. This activity is designed to help students identify their personal stressors and to determine which stress prevention strategies are most useful for them. Objectives: students will be able to (a) identify current…

  14. Photo elicitation interviews as a way of accessing primary school students' attitudes

    DEFF Research Database (Denmark)

    Nissen, Stine Karen; Schmidt, Maria Christina Secher; Tonnesen, Pia Beck

    2016-01-01

    explores the potential of photo-elicitation interviews as a qualitative path to affect. This particular type of interview is shaped as conversations about self-produced images of mathematics. When conducting the photo elicitation interviews, researchers also introduce their own photographs...

  15. Photo-Elicitation and Visual Semiotics: A Unique Methodology for Studying Inclusion for Children with Disabilities

    Science.gov (United States)

    Stockall, Nancy

    2013-01-01

    The methodology in this paper discusses the use of photographs as an elicitation strategy that can reveal the thinking processes of participants in a qualitatively rich manner. Photo-elicitation techniques combined with a Piercian semiotic perspective offer a unique method for creating a frame of action for later participant analysis. Illustrative…

  16. Episodic Development in Preschool Children's Play-Prompted and Direct-Elicited Narratives

    Science.gov (United States)

    Ilgaz, Hande; Aksu-Koc, Ayhan

    2005-01-01

    This study investigated the premise that action, manifested here through pretend play, is a semiotic arena that can enhance narrative development. It was hypothesized that children would produce structurally more complex narratives in play-prompted elicitation than in direct elicitation conditions, and that this competence would increase with age.…

  17. Role of phosphodiesterase-4 on ethanol elicited locomotion and narcosis.

    Science.gov (United States)

    Baliño, Pablo; Ledesma, Juan Carlos; Aragon, Carlos M G

    2016-02-01

    The cAMP signaling pathway has emerged as an important modulator of the pharmacological effects of ethanol. In this respect, the cAMP-dependent protein kinase has been shown to play an important role in the modulation of several ethanol-induced behavioral actions. Cellular levels of cAMP are maintained by the activity of adenylyl cyclases and phosphodiesterases. In the present work we have focused on ascertaining the role of PDE4 in mediating the neurobehavioral effects of ethanol. For this purpose, we have used the selective PDE4 inhibitor Ro 20-1724. This compound has been proven to enhance cellular cAMP response by PDE4 blockade and can be administered systemically. Swiss mice were injected intraperitoneally (i.p.) with Ro 20-1724 (0-5 mg/kg; i.p.) at different time intervals before ethanol (0-4 g/kg; i.p.) administration. Immediately after the ethanol injection, locomotor activity, loss of righting reflex, PKA footprint and enzymatic activity were assessed. Pretreatment with Ro 20-1724 increased ethanol-induced locomotor stimulation in a dose-dependent manner. Doses that increased locomotor stimulation did not modify basal locomotion or the suppression of motor activity produced by high doses of this alcohol. Ro 20-1724 did not alter the locomotor activation produced by amphetamine or cocaine. The time of loss of righting reflex evoked by ethanol was increased after pretreatment with Ro 20-1724. This effect was selective for the narcotic effects of ethanol since Ro 20-1724 did not affect pentobarbital-induced narcotic effects. Moreover, Ro 20-1724 administration increased the PKA footprint and enzymatic activity response elicited by ethanol. These data provide further evidence of the key role of the cAMP signaling pathway in the central effects of ethanol.

  18. Impact of discussion on preferences elicited in a group setting

    Directory of Open Access Journals (Sweden)

    Milne Ruairidh

    2006-03-01

    Full Text Available Abstract Background The completeness of preferences is assumed as one of the axioms of expected utility theory but has been subject to little empirical study. Methods Fifteen non-health professionals was recruited and familiarised with the standard gamble technique. The group then met five times over six months and preferences were elicited independently on 41 scenarios. After individual valuation, the group discussed the scenarios, following which preferences could be changed. Changes made were described and summary measures (mean and median before and after discussion compared using paired t test and Wilcoxon Signed Rank Test. Semi-structured telephone interviews were carried out to explore attitudes to discussing preferences. These were transcribed, read by two investigators and emergent themes described. Results Sixteen changes (3.6% were made to preferences by seven (47% of the fifteen members. The difference between individual preference values before and after discussion ranged from -0.025 to 0.45. The average effect on the group mean was 0.0053. No differences before and after discussion were statistically significant. The group valued discussion highly and suggested it brought four main benefits: reassurance; improved procedural performance; increased group cohesion; satisfying curiosity. Conclusion The hypothesis that preferences are incomplete cannot be rejected for a proportion of respondents. However, brief discussion did not result in substantial number of changes to preferences and these did not have significant impact on summary values for the group, suggesting that incompleteness, if present, may not have an important effect on cost-utility analyses.

  19. Divergent immune responses to house dust mite lead to distinct structural-functional phenotypes.

    Science.gov (United States)

    Johnson, Jill R; Swirski, Filip K; Gajewska, Beata U; Wiley, Ryan E; Fattouh, Ramzi; Pacitto, Stephanie R; Wong, Jonathan K; Stämpfli, Martin R; Jordana, Manel

    2007-09-01

    Asthma is a chronic airway inflammatory disease that encompasses three cardinal processes: T helper (Th) cell type 2 (Th2)-polarized inflammation, bronchial hyperreactivity, and airway wall remodeling. However, the link between the immune-inflammatory phenotype and the structural-functional phenotype remains to be fully defined. The objective of these studies was to evaluate the relationship between the immunologic nature of chronic airway inflammation and the development of abnormal airway structure and function in a mouse model of chronic asthma. Using IL-4-competent and IL-4-deficient mice, we created divergent immune-inflammatory responses to chronic aeroallergen challenge. Immune-inflammatory, structural, and physiological parameters of chronic allergic airway disease were evaluated in both strains of mice. Although both strains developed airway inflammation, the profiles of the immune-inflammatory responses were markedly different: IL-4-competent mice elicited a Th2-polarized response and IL-4-deficient mice developed a Th1-polarized response. Importantly, this chronic Th1-polarized immune response was not associated with airway remodeling or bronchial hyperresponsiveness. Transient reconstitution of IL-4 in IL-4-deficient mice via an airway gene transfer approach led to partial Th2 repolarization and increased bronchial hyperresponsiveness, along with full reconstitution of airway remodeling. These data show that distinct structural-functional phenotypes associated with chronic airway inflammation are strictly dependent on the nature of the immune-inflammatory response. PMID:17586699

  20. Comparison of elicitation methods for moral and affective beliefs in the theory of planned behaviour.

    Science.gov (United States)

    Dean, M; Arvola, A; Vassallo, M; Lähteenmäki, L; Raats, M M; Saba, A; Shepherd, R

    2006-09-01

    Although the theory of planned behaviour (TPB) has been applied successfully in the area of food choice, it has been criticized for its pure utilitarian approach to the factors determining behaviour. Despite the increase in predictive power of the model with added components such as affective attitude and moral and ethical concerns, in most studies the elicitation process still only addresses people's utilitarian beliefs about the behaviour with little attention paid to other aspects. This study compares the traditional method of elicitation of advantages and disadvantages with two other methods (word association and open-ended) in the elicitations of beliefs, attitudes and moral concerns in relation to the consumption of organic foods. Results show the traditional method to be best for eliciting cognitive beliefs, open-ended emotion task for eliciting emotional beliefs and open-ended beliefs task best for moral concerns. The advantages and disadvantages of each method are discussed. PMID:16782230

  1. Metaphors of Distress: Photo-Elicitation Enhances a Discourse Analysis of Parents' Accounts.

    Science.gov (United States)

    Kantrowitz-Gordon, Ira; Vandermause, Roxanne

    2016-07-01

    In research on sensitive topics, photo-elicitation can be a profound aid to data collection and interpretation processes. Photo-elicitation methods were used in this manner in a discourse analysis of parents' distress at least 6 months after preterm birth. After an initial interview, participants were asked to take digital photographs representing their distress and to return for a second interview to discuss the photographs. The elicited photo representations supported participants' engagement with their current or past distress and generated new meanings from the reappraisal of old photographs. Photo-elicitation demonstrated the embodiment of parents' distress in the child and the placement of distress in specific locations. Photographs of documents showed the power of the written word in generating and maintaining distress. Participants used existing photographs from their child's photo history to generate rich metaphors for their distress as parents. These findings have implications for enhancing interpretive health research by incorporating photo-elicitation methods.

  2. Azospirillum genomes reveal transition of bacteria from aquatic to terrestrial environments.

    OpenAIRE

    Florence Wisniewski-Dyé; Kirill Borziak; Gurusahai Khalsa-Moyers; Gladys Alexandre; Sukharnikov, Leonid O.; Kristin Wuichet; Gregory B Hurst; W Hayes McDonald; Robertson, Jon S.; Valérie Barbe; Alexandra Calteau; Zoé Rouy; Sophie Mangenot; Claire Prigent-Combaret; Philippe Normand

    2011-01-01

    International audience Fossil records indicate that life appeared in marine environments ∼3.5 billion years ago (Gyr) and transitioned to terrestrial ecosystems nearly 2.5 Gyr. Sequence analysis suggests that "hydrobacteria" and "terrabacteria" might have diverged as early as 3 Gyr. Bacteria of the genus Azospirillum are associated with roots of terrestrial plants; however, virtually all their close relatives are aquatic. We obtained genome sequences of two Azospirillum species and analyze...

  3. Immunomodulatory properties of probiotic bacteria

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen

    2007-01-01

    Certain lactic acid bacteria (LAB) are part of the commensal intestinal flora and considered beneficial for health, as they compete with pathogens for adhesion sites in the intestine and ferment otherwise indigestible compounds. Another important property of these so-called probiotic bacteria...... with bacteria, and the cytokine pattern induced by specific bacteria resembled the pattern induced in MoDC, except for TNF-alpha and IL-6, which were induced in response to different bacteria in blood DC/monocytes and monocyte-derived DC. Autologous NK cells produced IFN-gamma when cultured with blood DC......, monocytes and monocyte-derived DC and IL-12-inducing bacteria, whereas only DC induced IFN-gamma production in allogeneic T cells. In vitro-generated DC is a commonly used model of tissue DC, but they differ in certain aspects from intestinal DC, which are in direct contact with the intestinal microbiota...

  4. Cable Bacteria in Freshwater Sediments

    DEFF Research Database (Denmark)

    Risgaard-Petersen, Nils; Kristiansen, Michael; Frederiksen, Rasmus;

    2015-01-01

    In marine sediments cathodic oxygen reduction at the sediment surface can be coupled to anodic sulfide oxidation in deeper anoxic layers through electrical currents mediated by filamentous, multicellular bacteria of the Desulfobulbaceae family, the so-called cable bacteria. Until now, cable...... bacteria have only been reported from marine environments. In this study, we demonstrate that cable bacteria also occur in freshwater sediments. In a first step, homogenized sediment collected from the freshwater stream Giber Å, Denmark, was incubated in the laboratory. After 2 weeks, pH signatures...... marine cable bacteria, with the genus Desulfobulbus as the closest cultured lineage. The results of the present study indicate that electric currents mediated by cable bacteria could be important for the biogeochemistry in many more environments than anticipated thus far and suggest a common evolutionary...

  5. Functional tradeoffs underpin salinity-driven divergence in microbial community composition.

    Directory of Open Access Journals (Sweden)

    Chris L Dupont

    Full Text Available Bacterial community composition and functional potential change subtly across gradients in the surface ocean. In contrast, while there are significant phylogenetic divergences between communities from freshwater and marine habitats, the underlying mechanisms to this phylogenetic structuring yet remain unknown. We hypothesized that the functional potential of natural bacterial communities is linked to this striking divide between microbiomes. To test this hypothesis, metagenomic sequencing of microbial communities along a 1,800 km transect in the Baltic Sea area, encompassing a continuous natural salinity gradient from limnic to fully marine conditions, was explored. Multivariate statistical analyses showed that salinity is the main determinant of dramatic changes in microbial community composition, but also of large scale changes in core metabolic functions of bacteria. Strikingly, genetically and metabolically different pathways for key metabolic processes, such as respiration, biosynthesis of quinones and isoprenoids, glycolysis and osmolyte transport, were differentially abundant at high and low salinities. These shifts in functional capacities were observed at multiple taxonomic levels and within dominant bacterial phyla, while bacteria, such as SAR11, were able to adapt to the entire salinity gradient. We propose that the large differences in central metabolism required at high and low salinities dictate the striking divide between freshwater and marine microbiomes, and that the ability to inhabit different salinity regimes evolved early during bacterial phylogenetic differentiation. These findings significantly advance our understanding of microbial distributions and stress the need to incorporate salinity in future climate change models that predict increased levels of precipitation and a reduction in salinity.

  6. Radiation-resistant asporogenic bacteria

    International Nuclear Information System (INIS)

    This paper reports the biological and ecological examinations on the radiation-resistant asporogenic bacteria (mainly concerning Micrococcus radiodurans). Radiation-resistant asporogenic bacteria were isolated from the irradiated areas of the natural world as well as from the general areas and from the Rn waters in the Misasa hot spring. The acquiring of the tolerance to radiation in bacteria was also examined. In addition, the future problems of microbiological treatment with irradiation were mentioned. (Tsukamoto, Y.)

  7. Bacteriophages of methanotrophic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Tyutikow, F.M. (All-Union Research Inst. for Genetics and Selection of Industrial Microorganisms, Moscow, USSR); Bespalova, I.A.; Rebentish, B.A.; Aleksandrushkina, N.N.; Krivisky, A.S.

    1980-10-01

    Bacteriophages of methanotrophic bacteria have been found in 16 out of 88 studied samples (underground waters, pond water, soil, gas and oil installation waters, fermentor cultural fluids, bacterial paste, and rumen of cattle) taken in different geographic zones of the Soviet Union. Altogether, 23 phage strains were isolated. By fine structure, the phages were divided into two types (with very short or long noncontractile tails); by host range and serological properties, they fell into three types. All phages had guanine- and cytosine-rich double-stranded deoxyribonucleic acid consisting of common nitrogen bases. By all of the above-mentioned properties, all phages within each of the groups were completely identical to one another, but differed from phages of other groups.

  8. Bacteria, phages and septicemia.

    Directory of Open Access Journals (Sweden)

    Ausra Gaidelyte

    Full Text Available The use of phages is an attractive option to battle antibiotic resistant bacteria in certain bacterial infections, but the role of phage ecology in bacterial infections is obscure. Here we surveyed the phage ecology in septicemia, the most severe type of bacterial infection. We observed that the majority of the bacterial isolates from septicemia patients spontaneously secreted phages active against other isolates of the same bacterial strain, but not to the strain causing the disease. Such phages were also detected in the initial blood cultures, indicating that phages are circulating in the blood at the onset of sepsis. The fact that most of the septicemic bacterial isolates carry functional prophages suggests an active role of phages in bacterial infections. Apparently, prophages present in sepsis-causing bacterial clones play a role in clonal selection during bacterial invasion.

  9. Estimating a geographically explicit model of population divergence.

    Science.gov (United States)

    Knowles, L Lacey; Carstens, Bryan C

    2007-03-01

    Patterns of genetic variation can provide valuable insights for deciphering the relative roles of different evolutionary processes in species differentiation. However, population-genetic models for studying divergence in geographically structured species are generally lacking. Since these are the biogeographic settings where genetic drift is expected to predominate, not only are population-genetic tests of hypotheses in geographically structured species constrained, but generalizations about the evolutionary processes that promote species divergence may also be potentially biased. Here we estimate a population-divergence model in montane grasshoppers from the sky islands of the Rocky Mountains. Because this region was directly impacted by Pleistocene glaciation, both the displacement into glacial refugia and recolonization of montane habitats may contribute to differentiation. Building on the tradition of using information from the genealogical relationships of alleles to infer the geography of divergence, here the additional consideration of the process of gene-lineage sorting is used to obtain a quantitative estimate of population relationships and historical associations (i.e., a population tree) from the gene trees of five anonymous nuclear loci and one mitochondrial locus in the broadly distributed species Melanoplus oregonensis. Three different approaches are used to estimate a model of population divergence; this comparison allows us to evaluate specific methodological assumptions that influence the estimated history of divergence. A model of population divergence was identified that significantly fits the data better compared to the other approaches, based on per-site likelihood scores of the multiple loci, and that provides clues about how divergence proceeded in M. oregonensis during the dynamic Pleistocene. Unlike the approaches that either considered only the most recent coalescence (i.e., information from a single individual per population) or did not

  10. A New Measure of Fuzzy Directed Divergence and Its Application in Image Segmentation

    Directory of Open Access Journals (Sweden)

    P.K Bhatia

    2013-03-01

    Full Text Available An approach to develop new measures of fuzzy directed divergence is proposed here. A new measure of fuzzy directed divergence is proposed, and some mathematical properties of this measure are proved. The application of fuzzy directed divergence in image segmentation is explained. The proposed technique minimizes the fuzzy divergence or the separation between the actual and ideal thresholded image.

  11. Expression Divergence of Tandemly Arrayed Genes in Human and Mouse

    Directory of Open Access Journals (Sweden)

    Valia Shoja

    2007-01-01

    Full Text Available Tandemly arrayed genes (TAGs account for about one third of the duplicated genes in eukaryotic genomes, yet there has not been any systematic study of their gene expression patterns. Taking advantage of recently published large-scale microarray data sets, we studied the expression divergence of 361 two-member TAGs in human and 212 two-member TAGs in mouse and examined the effect of sequence divergence, gene orientation, and chromosomal proximity on the divergence of TAG expression patterns. Our results show that there is a weak negative correlation between sequence divergence of TAG members and their expression similarity. There is also a weak negative correlation between chromosomal proximity of TAG members and their expression similarity. We did not detect any significant relationship between gene orientation and expression similarity. We also found that downstream TAG members do not show significantly narrower expression breadth than upstream members, contrary to what we predict based on TAG expression divergence hypothesis that we propose. Finally, we show that both chromosomal proximity and expression correlation in TAGs do not differ significantly from their neighboring non-TAG gene pairs, suggesting that tandem duplication is unlikely to be the cause for the higher-than-random expression association between neighboring genes on a chromosome in human and mouse.

  12. Sufficient Statistics for Divergence and the Probability of Misclassification

    Science.gov (United States)

    Quirein, J.

    1972-01-01

    One particular aspect is considered of the feature selection problem which results from the transformation x=Bz, where B is a k by n matrix of rank k and k is or = to n. It is shown that in general, such a transformation results in a loss of information. In terms of the divergence, this is equivalent to the fact that the average divergence computed using the variable x is less than or equal to the average divergence computed using the variable z. A loss of information in terms of the probability of misclassification is shown to be equivalent to the fact that the probability of misclassification computed using variable x is greater than or equal to the probability of misclassification computed using variable z. First, the necessary facts relating k-dimensional and n-dimensional integrals are derived. Then the mentioned results about the divergence and probability of misclassification are derived. Finally it is shown that if no information is lost (in x = Bz) as measured by the divergence, then no information is lost as measured by the probability of misclassification.

  13. Total Bregman divergence and its applications to DTI analysis.

    Science.gov (United States)

    Vemuri, Baba C; Liu, Meizhu; Amari, Shun-Ichi; Nielsen, Frank

    2011-02-01

    Divergence measures provide a means to measure the pairwise dissimilarity between "objects," e.g., vectors and probability density functions (pdfs). Kullback-Leibler (KL) divergence and the square loss (SL) function are two examples of commonly used dissimilarity measures which along with others belong to the family of Bregman divergences (BD). In this paper, we present a novel divergence dubbed the Total Bregman divergence (TBD), which is intrinsically robust to outliers, a very desirable property in many applications. Further, we derive the TBD center, called the t-center (using the l(1)-norm), for a population of positive definite matrices in closed form and show that it is invariant to transformation from the special linear group. This t-center, which is also robust to outliers, is then used in tensor interpolation as well as in an active contour based piecewise constant segmentation of a diffusion tensor magnetic resonance image (DT-MRI). Additionally, we derive the piecewise smooth active contour model for segmentation of DT-MRI using the TBD and present several comparative results on real data.

  14. Rotational and divergent kinetic energy in the mesoscale model ALADIN

    Directory of Open Access Journals (Sweden)

    V. Blažica

    2013-03-01

    Full Text Available Kinetic energy spectra from the mesoscale numerical weather prediction (NWP model ALADIN with horizontal resolution 4.4 km are split into divergent and rotational components which are then compared at horizontal scales below 300 km and various vertical levels. It is shown that about 50% of kinetic energy in the free troposphere in ALADIN is divergent energy. The percentage increases towards 70% near the surface and in the upper troposphere towards 100 hPa. The maximal percentage of divergent energy is found at stratospheric levels around 100 hPa and at scales below 100 km which are not represented by the global models. At all levels, the divergent energy spectra are characterised by shallower slopes than the rotational energy spectra, and the difference increases as horizontal scales become larger. A very similar vertical distribution of divergent energy is obtained by using the standard ALADIN approach for the computation of spectra based on the extension zone and by applying detrending approach commonly used in mesoscale NWP community.

  15. Concrete ensemble Kalman filters with rigorous catastrophic filter divergence.

    Science.gov (United States)

    Kelly, David; Majda, Andrew J; Tong, Xin T

    2015-08-25

    The ensemble Kalman filter and ensemble square root filters are data assimilation methods used to combine high-dimensional, nonlinear dynamical models with observed data. Ensemble methods are indispensable tools in science and engineering and have enjoyed great success in geophysical sciences, because they allow for computationally cheap low-ensemble-state approximation for extremely high-dimensional turbulent forecast models. From a theoretical perspective, the dynamical properties of these methods are poorly understood. One of the central mysteries is the numerical phenomenon known as catastrophic filter divergence, whereby ensemble-state estimates explode to machine infinity, despite the true state remaining in a bounded region. In this article we provide a breakthrough insight into the phenomenon, by introducing a simple and natural forecast model that transparently exhibits catastrophic filter divergence under all ensemble methods and a large set of initializations. For this model, catastrophic filter divergence is not an artifact of numerical instability, but rather a true dynamical property of the filter. The divergence is not only validated numerically but also proven rigorously. The model cleanly illustrates mechanisms that give rise to catastrophic divergence and confirms intuitive accounts of the phenomena given in past literature.

  16. Sandwiched Rényi divergence satisfies data processing inequality

    Energy Technology Data Exchange (ETDEWEB)

    Beigi, Salman [School of Mathematics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5746, Tehran (Iran, Islamic Republic of)

    2013-12-15

    Sandwiched (quantum) α-Rényi divergence has been recently defined in the independent works of Wilde et al. [“Strong converse for the classical capacity of entanglement-breaking channels,” preprint http://arxiv.org/abs/arXiv:1306.1586 (2013)] and Müller-Lennert et al. [“On quantum Rényi entropies: a new definition, some properties and several conjectures,” preprint http://arxiv.org/abs/arXiv:1306.3142v1 (2013)]. This new quantum divergence has already found applications in quantum information theory. Here we further investigate properties of this new quantum divergence. In particular, we show that sandwiched α-Rényi divergence satisfies the data processing inequality for all values of α > 1. Moreover we prove that α-Holevo information, a variant of Holevo information defined in terms of sandwiched α-Rényi divergence, is super-additive. Our results are based on Hölder's inequality, the Riesz-Thorin theorem and ideas from the theory of complex interpolation. We also employ Sion's minimax theorem.

  17. Scalar field quantization without divergences in all spacetime dimensions

    Science.gov (United States)

    Klauder, John R.

    2011-07-01

    Covariant, self-interacting scalar quantum field theories admit solutions for low enough spacetime dimensions, but when additional divergences appear in higher dimensions, the traditional approach leads to results, such as triviality, that are less than satisfactory. Guided by idealized but soluble nonrenormalizable models, a nontraditional proposal for the quantization of covariant scalar field theories is advanced, which achieves a term-by-term, divergence-free, perturbation analysis of interacting models expanded about a suitable pseudofree theory, which differs from a free theory by an O(planck2) counterterm. These positive features are realized within a functional integral formulation by a local, nonclassical, counterterm that effectively transforms parameter changes in the action from generating mutually singular measures, which are the basis for divergences, to equivalent measures, thereby removing all divergences. The use of an alternative model about which to perturb is already supported by properties of the classical theory and is allowed by the inherent ambiguity in the quantization process itself. This procedure not only provides acceptable solutions for models for which no acceptable, faithful solution currently exists, e.g. phiv4n, for spacetime dimensions n >= 4, but offers a new, divergence-free solution for less-singular models as well, e.g. phiv4n, for n = 2, 3. Our analysis implies similar properties for multicomponent scalar models, such as those associated with the Higgs model.

  18. Genome-wide functional divergence after the symbiosis of proteobacteria with insects unraveled through a novel computational approach.

    Directory of Open Access Journals (Sweden)

    Christina Toft

    2009-04-01

    Full Text Available Symbiosis has been among the most important evolutionary steps to generate biological complexity. The establishment of symbiosis required an intimate metabolic link between biological systems with different complexity levels. The strict endo-cellular symbiotic bacteria of insects are beautiful examples of the metabolic coupling between organisms belonging to different kingdoms, a eukaryote and a prokaryote. The host (eukaryote provides the endosymbiont (prokaryote with a stable cellular environment while the endosymbiont supplements the host's diet with essential metabolites. For such communication to take place, endosymbionts' genomes have suffered dramatic modifications and reconfigurations of proteins' functions. Two of the main modifications, loss of genes redundant for endosymbiotic bacteria or the host and bacterial genome streamlining, have been extensively studied. However, no studies have accounted for possible functional shifts in the endosymbiotic proteomes. Here, we develop a simple method to screen genomes for evidence of functional divergence between two species clusters, and we apply it to identify functional shifts in the endosymbiotic proteomes. Despite the strong effects of genetic drift in the endosymbiotic systems, we unexpectedly identified genes to be under stronger selective constraints in endosymbionts of aphids and ants than in their free-living bacterial relatives. These genes are directly involved in supplementing the host's diet with essential metabolites. A test of functional divergence supports a strong relationship between the endosymbiosis and the functional shifts of proteins involved in the metabolic communication with the insect host. The correlation between functional divergence in the endosymbiotic bacterium and the ecological requirements of the host uncovers their intimate biochemical and metabolic communication and provides insights on the role of symbiosis in generating species diversity.

  19. Noise Characteristics of Overexpanded Jets from Convergent-Divergent Nozzles

    Science.gov (United States)

    Zaman, K. B. M. Q.

    2008-01-01

    A broadband noise component occurring in the overexpanded flow regime with convergent-divergent nozzles is identified. Relative to a convergent nozzle, at same pressure ratios, this excess noise can lead to a large increase in the overall sound pressure levels. Several features distinguish it from the more familiar broadband shock associated noise. Unlike the latter, it is observed even at shallow polar locations and there is no noticeable shift of the spectral content in frequency with observation angle. The amplitudes are found to be more pronounced with nozzles having larger half-angle of the divergent section. The noise apparently occurs when a shock resides within the divergent section of the nozzle and results from random unsteady motion of the shock.

  20. Ice flux divergence anomalies on 79north Glacier, Greenland

    DEFF Research Database (Denmark)

    Seroussi, H.; Morlighem, M.; Rignot, E.;

    2011-01-01

    The ice flux divergence of a glacier is an important quantity to examine because it determines the rate of temporal change of its thickness. Here, we combine high-resolution ice surface velocity observations of Nioghalvfjerdsfjorden (79north) Glacier, a major outlet glacier in north Greenland......, with a dense grid of ice thickness data collected with an airborne radar sounder in 1998, to examine its ice flux divergence. We detect large variations, up to 100 m/yr, in flux divergence on grounded ice that are incompatible with what we know of the glacier surface mass balance, basal mass balance...... onto a regular grid using a scheme (here block kriging) that does not conserve mass or ice flux. This problem is not unique to 79north Glacier but is common to all conventional ice thickness surveys of glaciers and ice sheets; and fundamentally limits the application of ice thickness grids to high...

  1. Android Malware Detection Using Kullback-Leibler Divergence

    Directory of Open Access Journals (Sweden)

    Vanessa N. COOPER

    2015-03-01

    Full Text Available Many recent reports suggest that mareware applications cause high billing to victims by sending and receiving hidden SMS messages. Given that, there is a need to develop necessary technique to identify malicious SMS operations as well as differentiate between good and bad SMS operations within applications.In this paper, we apply Kullback-Leibler Divergence (KLD as a distance metric to identify the difference between good and bad SMS operations. We develop a set of elements that represent sending or receiving of SMS messages, both legitimately and maliciously. Then, we compare the divergence of the trained set of elements. Our evaluation shows that the divergence between good and bad applications remains significantly high, whereas between two applications performing the same SMS operations remain low. We evaluate the proposed KLD-based concept for identifying a set of malware applications. The initial results show that our approach can identify all known malware and has less false positive warning.

  2. A genomic island linked to ecotype divergence in Atlantic cod

    DEFF Research Database (Denmark)

    Hansen, Jakob Hemmer; Eg Nielsen, Einar; Therkildsen, Nina O.;

    2013-01-01

    gene flow and large effective population sizes, properties which theoretically could restrict divergence in local genomic regions. We identify a genomic region of strong population differentiation, extending over approximately 20 cM, between pairs of migratory and stationary ecotypes examined at two......The genomic architecture underlying ecological divergence and ecological speciation with gene flow is still largely unknown for most organisms. One central question is whether divergence is genome‐wide or localized in ‘genomic mosaics’ during early stages when gene flow is still pronounced....... Empirical work has so far been limited, and the relative impacts of gene flow and natural selection on genomic patterns have not been fully explored. Here, we use ecotypes of Atlantic cod to investigate genomic patterns of diversity and population differentiation in a natural system characterized by high...

  3. Sub-lethal levels of electric current elicit the biosynthesis of plant secondary metabolites.

    Science.gov (United States)

    Kaimoyo, Evans; Farag, Mohamed A; Sumner, Lloyd W; Wasmann, Catherine; Cuello, Joel L; VanEtten, Hans

    2008-01-01

    Many secondary metabolites that are normally undetectable or in low amounts in healthy plant tissue are synthesized in high amounts in response to microbial infection. Various abiotic and biotic agents have been shown to mimic microorganisms and act as elicitors of the synthesis of these plant compounds. In the present study, sub-lethal levels of electric current are shown to elicit the biosynthesis of secondary metabolites in transgenic and non-transgenic plant tissue. The production of the phytoalexin (+)-pisatin by pea was used as the main model system. Non-transgenic pea hairy roots treated with 30-100 mA of electric current produced 13 times higher amounts of (+)-pisatin than did the non-elicited controls. Electrically elicited transgenic pea hairy root cultures blocked at various enzymatic steps in the (+)-pisatin biosynthetic pathway also accumulated intermediates preceding the blocked enzymatic step. Secondary metabolites not usually produced by pea accumulated in some of the transgenic root cultures after electric elicitation due to the diversion of the intermediates into new pathways. The amount of pisatin in the medium bathing the roots of electro-elicited roots of hydroponically cultivated pea plants was 10 times higher 24 h after elicitation than in the medium surrounding the roots of non-elicited control plants, showing not only that the electric current elicited (+)-pisatin biosynthesis but also that the (+)-pisatin was released from the roots. Seedlings, intact roots or cell suspension cultures of fenugreek (Trigonella foenum-graecum), barrel medic, (Medicago truncatula), Arabidopsis thaliana, red clover (Trifolium pratense) and chickpea (Cicer arietinum) also produced increased levels of secondary metabolites in response to electro-elicitation. On the basis of our results, electric current would appear to be a general elicitor of plant secondary metabolites and to have potential for application in both basic and commercial research. PMID:18331050

  4. Phenotypic and genetic divergence within a single whitefish form - detecting the potential for future divergence.

    Science.gov (United States)

    Hirsch, Philipp Emanuel; Eckmann, Reiner; Oppelt, Claus; Behrmann-Godel, Jasminca

    2013-12-01

    Human-induced nutrient input can change the selection regime and lead to the loss of biodiversity. For example, eutrophication caused speciation reversal in polymorphic whitefish populations through a flattening of littoral-pelagic selection gradients. We investigated the current state of phenotypic and genetic diversity in whitefish (Coregonus macrophthalmus) in a newly restored lake whose nutrient load has returned to pre-eutrophication levels and found that whitefish spawning at different depths varied phenotypically and genetically: individuals spawning at shallower depth had fewer gill rakers, faster growth, and a morphology adapted to benthic feeding, and they showed higher degrees of diet specialization than deeper spawning individuals. Microsatellite analyses complemented the phenotype analyses by demonstrating reproductive isolation along different spawning depths. Our results indicate that whitefish still retain or currently regain phenotypic and genetic diversity, which was lost during eutrophication. Hence, the population documented here has a potential for future divergence because natural selection can target phenotypes specialized along re-established littoral-pelagic selection gradients. The biodiversity, however, will have better chances to return if managers acknowledge the evolutionary potential within the local whitefish and adapt fishing and stocking measures. PMID:24478795

  5. Swimming bacteria in liquid crystal

    Science.gov (United States)

    Sokolov, Andrey; Zhou, Shuang; Aranson, Igor; Lavrentovich, Oleg

    2014-03-01

    Dynamics of swimming bacteria can be very complex due to the interaction between the bacteria and the fluid, especially when the suspending fluid is non-Newtonian. Placement of swimming bacteria in lyotropic liquid crystal produces a new class of active materials by combining features of two seemingly incompatible constituents: self-propelled live bacteria and ordered liquid crystals. Here we present fundamentally new phenomena caused by the coupling between direction of bacterial swimming, bacteria-triggered flows and director orientations. Locomotion of bacteria may locally reduce the degree of order in liquid crystal or even trigger nematic-isotropic phase transition. Microscopic flows generated by bacterial flagella disturb director orientation. Emerged birefringence patterns allow direct optical observation and quantitative characterization of flagella dynamics. At high concentration of bacteria we observed the emergence of self-organized periodic texture caused by bacteria swimming. Our work sheds new light on self-organization in hybrid bio-mechanical systems and can lead to valuable biomedical applications. Was supported by the US DOE, Office of Basic Energy Sciences, Division of Materials Science and Engineering, under the Contract No. DE AC02-06CH11357.

  6. Convergence Analysis of Contrastive Divergence Algorithm Based on Gradient Method with Errors

    OpenAIRE

    Xuesi Ma; Xiaojie Wang

    2015-01-01

    Contrastive Divergence has become a common way to train Restricted Boltzmann Machines; however, its convergence has not been made clear yet. This paper studies the convergence of Contrastive Divergence algorithm. We relate Contrastive Divergence algorithm to gradient method with errors and derive convergence conditions of Contrastive Divergence algorithm using the convergence theorem of gradient method with errors. We give specific convergence conditions of Contrastive Divergence ...

  7. Repeated adaptive divergence of microhabitat specialization in avian feather lice

    Directory of Open Access Journals (Sweden)

    Johnson Kevin P

    2012-06-01

    Full Text Available Abstract Background Repeated adaptive radiations are evident when phenotypic divergence occurs within lineages, but this divergence into different forms is convergent when compared across lineages. Classic examples of such repeated adaptive divergence occur in island (for example, Caribbean Anolis lizards and lake systems (for example, African cichlids. Host-parasite systems in many respects are analogous to island systems, where host species represent isolated islands for parasites whose life cycle is highly tied to that of their hosts. Thus, host-parasite systems might exhibit interesting cases of repeated adaptive divergence as seen in island and lake systems. The feather lice of birds spend their entire life cycle on the body of the host and occupy distinct microhabitats on the host: head, wing, body and generalist. These microhabitat specialists show pronounced morphological differences corresponding to how they escape from host preening. We tested whether these different microhabitat specialists were a case of repeated adaptive divergence by constructing both morphological and molecular phylogenies for a diversity of avian feather lice, including many examples of head, wing, body and generalist forms. Results Morphological and molecular based phylogenies were highly incongruent, which could be explained by rampant convergence in morphology related to microhabitat specialization on the host. In many cases lice from different microhabitat specializations, but from the same group of birds, were sister taxa. Conclusions This pattern indicates a process of repeated adaptive divergence of these parasites within host group, but convergence when comparing parasites across host groups. These results suggest that host-parasite systems might be another case in which repeated adaptive radiations could be relatively common, but potentially overlooked, because morphological convergence can obscure evolutionary relationships.

  8. Using expert elicitation to prioritize resource allocation for risk identification for nanosilver.

    Science.gov (United States)

    Fauss, Emma; Gorman, Michael E; Swami, Nathan

    2009-01-01

    This article introduces a method to identify risks through expert elicitation, using silver nanotechnology as a case study. Unique features of the method include supplying experts with a list of silver nanotechnology products, and conducting the elicitation in an extended interview format that captures the experts' reasoning. The end result is a series of graphical representations of expert thinking from which high-risk scenarios and knowledge gaps can be reliably inferred. This methodology, combined with other approaches to expert elicitation, can help identify knowledge and oversight gaps, and can be used as part of an adaptive management strategy. PMID:20122116

  9. Evolution of Weighted Networks by Duplication-Divergence Mechanism

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-Guo; YAN Jia-Ren; LIU Zi-Ran; WANG Li

    2006-01-01

    @@ The duplication and divergence process is ubiquitous in nature and man-made networks. Motivated by the duplication-divergence mechanism which depicts the growth of protein networks, we propose a weighted network model in which topological evolution is coupled with weight dynamics. Large scale numerical results indicate that our model can naturally generate networks with power-law-like distributions of degree, strength and weight.The degree-strength correlation is illustrated as well. These properties are in agreement well with empirical data observed in real-world systems. Furthermore, by altering the retention probability σ, weighted, structured exponential networks are realized.

  10. The direct Flow parametric Proof of Gauss' Divergence Theorem revisited

    DEFF Research Database (Denmark)

    Markvorsen, Steen

    The standard proof of the divergence theorem in undergraduate calculus courses covers the theorem for static domains between two graph surfaces. We show that within first year undergraduate curriculum, the flow proof of the dynamic version of the divergence theorem - which is usually considered...... only much later in more advanced math courses - is comprehensible with only a little extension of the first year curriculum. Moreover, it is more intuitive than the static proof. We support this intuition further by unfolding and visualizing a few examples with increasing complexity. In these examples...

  11. Investigation of bias of hedonic scores when co-eliciting product attribute information using CATA questions

    DEFF Research Database (Denmark)

    Jaeger, Sara R.; Giacalone, Davide; Roigard, Cristina M.;

    2013-01-01

    have been claimed to have a smaller effect on hedonic scores than other attribute such as just-about-right or intensity scales. In this research, nine studies using consumers as participants examined effects on hedonic product scores when sensory attribute information was co-elicited using CATA...... (appearance, aroma, flavour, taste, aftertaste, mouthfeel). The present research suggests that co-elicitation of hedonic scores and product attribute information using CATA questions may bias the hedonic scores, but not that it certainly will do so. This needs to be recognised, leading to more widespread...... acceptance that co-elicitation has merit. Investigators should decide on whether or not to co-elicit product attribute information using CATA questions on a case-by-case basis, acknowledging that bias may occur. Further research is needed to understand when/when not bias is likely to occur....

  12. Intra-administration associations and withdrawal symptoms: morphine-elicited morphine withdrawal.

    Science.gov (United States)

    McDonald, Robert V; Siegel, Shepard

    2004-02-01

    On the basis of a conditioning analysis, some drug "withdrawal symptoms" are conditional responses elicited by stimuli paired with the drug effect. Prior demonstrations of conditional elicitation of withdrawal symptoms evaluated the role of environmental cues; however, pharmacological cues also typically signal a drug effect. Within each administration, early drug onset cues (DOCs) may become associated with the later, larger drug effect (intra-administration associations). This experiment evaluated the contribution of intra-administration associations to withdrawal symptoms. The results indicated that (a). 5 mg/kg morphine elicited behavioral and thermic withdrawal symptoms in rats previously injected on a number of occasions with 50 mg/kg morphine and that (b). DOC-elicited withdrawal symptoms are not a sensitized response to the opiate but rather an associative phenomenon. PMID:14769091

  13. Auditory evoked fields elicited by spectral, temporal, and spectral-temporal changes in human cerebral cortex

    Directory of Open Access Journals (Sweden)

    Hidehiko eOkamoto

    2012-05-01

    Full Text Available Natural sounds contain complex spectral components, which are temporally modulated as time-varying signals. Recent studies have suggested that the auditory system encodes spectral and temporal sound information differently. However, it remains unresolved how the human brain processes sounds containing both spectral and temporal changes. In the present study, we investigated human auditory evoked responses elicited by spectral, temporal, and spectral-temporal sound changes by means of magnetoencephalography (MEG. The auditory evoked responses elicited by the spectral-temporal change were very similar to those elicited by the spectral change, but those elicited by the temporal change were delayed by 30 – 50 ms and differed from the others in morphology. The results suggest that human brain responses corresponding to spectral sound changes precede those corresponding to temporal sound changes, even when the spectral and temporal changes occur simultaneously.

  14. EXPERT ELICITATION OF ACROSS-TECHNOLOGY CORRELATIONS FOR REACTOR CAPITAL COSTS

    Energy Technology Data Exchange (ETDEWEB)

    Brent Dixon; Various

    2014-06-01

    Calculations of the uncertainty in the Levelized Cost at Equilibrium (LCAE) of generating nuclear electricity typically assume that the costs of the system component, notably reactors, are uncorrelated. Partial cancellation of independent errors thus gives rise to unrealistically small cost uncertainties for fuel cycles that incorporate multiple reactor technologies. This summary describes an expert elicitation of correlations between overnight reactor construction costs. It also defines a method for combining the elicitations into a single, consistent correlation matrix suitable for use in Monte Carlo LCAE calculations. Both the elicitation and uncertainty propagation methods are demonstrated through a pilot study where cost correlations between eight reactor technologies were elicited from experts in the US DOE Fuel Cycle Research

  15. A Systematic Review to Identify the Use of Preference Elicitation Methods in Healthcare Decision Making

    NARCIS (Netherlands)

    Weernink, Marieke G.M.; Janus, Sarah I.M.; Til, van Janine A.; Raisch, D.W.; Manen, van Jeannette G.; IJzerman, Maarten J.

    2014-01-01

    Introduction Preference elicitation methods help to increase patient-centred medical decision making (MDM) by measuring benefit and value. Preferences can be applied in decisions regarding reimbursement, including health technology assessment (HTA); market access, including benefit–risk assessment (

  16. Effects of Partially N-acetylated Chitosans to Elicit Resistance Reaction on Brassica napus L.

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xue-kun; TANG Zhang-lin; CHEN Li; GUO Yi-hong; CHEN Yun-ping; LI Jia-na

    2002-01-01

    The effects to elicit resistance reaction on oilseed rape (Brassica napus L. cv Xinongchangjiao )by four partially N-acetylated chitosan 7B, 8B, 9B and 10B (Degree of acetylation (D. A. ) is 30%, 20%,10%, 0%, respectively) and Glycol chitosan (GC, D.A. is 0%) were investigated and compared. Results showed that chitosan were similar to salicylic acid (SA), and could induce resistance reaction, but the reaction was influenced by the degree of acetylation of chitosan. Fully deacetylated chitosans, 10B and GC, elicited chitinase activity, but partially acetylated chitosan, 7B, 8B and 9B, inhibited chitinase activity. Phenyalanine ammonia-lyase (PAL) was also elicited. Elicitor activity increased with on increasing degree of acetylation, 7B induced highest PAL activity among all chitosans. All chitosans induced peroxidase (POD) in a similar level.After elicited by glycol chitosan, like SA treatment, the seedlings increased disease resistance to Sclerotinia sclerotiorum significantly.

  17. Conditioning stimulation techniques for enhancement of transcranially elicited evoked motor responses

    NARCIS (Netherlands)

    Journee, H. -L.; Polak, H. E.; De Kleuver, M.

    2007-01-01

    Introduction. - In spite of the use of multipulse, transcranial electrical stimulation (TES) is still insufficient in a subgroup of patients to elicit motor-evoked potentials during intraoperative neurophysiological monitoring (IONM). Classic facilitation methods used in awake patients are precluded

  18. Modeling Elicitation effects in contingent valuation studies: a Monte Carlo Analysis of the bivariate approach

    OpenAIRE

    Genius, Margarita; Strazzera, Elisabetta

    2005-01-01

    A Monte Carlo analysis is conducted to assess the validity of the bivariate modeling approach for detection and correction of different forms of elicitation effects in Double Bound Contingent Valuation data. Alternative univariate and bivariate models are applied to several simulated data sets, each one characterized by a specific elicitation effect, and their performance is assessed using standard selection criteria. The bivariate models include the standard Bivariate Probit model, and an al...

  19. Quality Requirements Elicitation based on Inquiry of Quality-Impact Relationships

    OpenAIRE

    Fotrousi, Farnaz; Fricker, Samuel (Ed.); Fiedler, Markus

    2014-01-01

    Quality requirements, an important class of non functional requirements, are inherently difficult to elicit. Particularly challenging is the definition of good-enough quality. The problem cannot be avoided though, because hitting the right quality level is critical. Too little quality leads to churn for the software product. Excessive quality generates unnecessary cost and drains the resources of the operating platform. To address this problem, we propose to elicit the specific relationships ...

  20. Sinalbins A and B, phytoalexins from Sinapis alba: elicitation, isolation, and synthesis.

    Science.gov (United States)

    Pedras, M S; Zaharia, I L

    2000-10-01

    The chemical structure and synthesis of sinalbin A is described. This cruciferous phytoalexin is produced by white mustard (Sinapis alba) after treatment with biotic and abiotic elicitors. In addition, a related metabolite, named sinalbin B, is present in extracts from elicited plants, but not in those from non-elicited controls. Sinalbin B, which was also synthesized, appears to be both a phytoalexin and a biosynthetic precursor of sinalbin A. PMID:11142844

  1. The Future Prospect of PV and CSP Solar Technologies: An Expert Elicitation Survey

    OpenAIRE

    Bosetti, Valentina; CATENACCI Michela; Fiorese, Giulia; Verdolini, Elena

    2012-01-01

    In this paper we present and discuss the results of an expert elicitation survey on solar technologies. Sixteen leading European experts from the academic world, the private sector and international institutions took part in this expert elicitation survey on Photovoltaic (PV) and Concentrated Solar Power (CSP) technologies. The survey collected probabilistic information on (1) how Research, Development and Demonstration (RD&D) investments will impact the future costs of solar technologies and...

  2. Evaluation of Antioxidant and Antibacterial Potentials of Nigella sativa L. Suspension Cultures under Elicitation

    Directory of Open Access Journals (Sweden)

    Hera Chaudhry

    2015-01-01

    Full Text Available Nigella sativa L. (family Ranunculaceae is an annual herb of immense medicinal properties because of its major active components (i.e., thymoquinone (TQ, thymohydroquinone (THQ, and thymol (THY. Plant tissue culture techniques like elicitation, Agrobacterium mediated transformation, hairy root culture, and so on, are applied for substantial metabolite production. This study enumerates the antibacterial and antioxidant potentials of N. sativa epicotyl suspension cultures under biotic and abiotic elicitation along with concentration optimization of the elicitors for enhanced TQ and THY production. Cultures under different concentrations of pectin and manganese chloride (MnCl2 elicitation (i.e., 5 mg/L, 10 mg/L, and 15 mg/L showed that the control, MnCl2 10 mg/L, and pectin 15 mg/L suspension extracts greatly inhibited the growth of E. coli, S. typhimurium, and S. aureus (MIC against E. coli, i.e., 2.35±0.8, 2.4±0.2, and 2.46±0.5, resp.. Elicitation decreased SOD enzyme activity whereas CAT enzyme activity increased remarkably under MnCl2 elicitation. MnCl2 10 mg/L and pectin 15 mg/L elicitation enhanced the DPPH radical inhibition ability, but ferric scavenging activity was comparable to the control. TQ and THY were quantified by LC-MS/MS in the cultures with high bioactive properties revealing maximum content under MnCl2 10 mg/L elicitation. Therefore, MnCl2 elicitation can be undertaken on large scale for sustainable metabolite production.

  3. Micropolar Fluids Using B-spline Divergence Conforming Spaces

    KAUST Repository

    Sarmiento, Adel

    2014-06-06

    We discretized the two-dimensional linear momentum, microrotation, energy and mass conservation equations from micropolar fluids theory, with the finite element method, creating divergence conforming spaces based on B-spline basis functions to obtain pointwise divergence free solutions [8]. Weak boundary conditions were imposed using Nitsche\\'s method for tangential conditions, while normal conditions were imposed strongly. Once the exact mass conservation was provided by the divergence free formulation, we focused on evaluating the differences between micropolar fluids and conventional fluids, to show the advantages of using the micropolar fluid model to capture the features of complex fluids. A square and an arc heat driven cavities were solved as test cases. A variation of the parameters of the model, along with the variation of Rayleigh number were performed for a better understanding of the system. The divergence free formulation was used to guarantee an accurate solution of the flow. This formulation was implemented using the framework PetIGA as a basis, using its parallel stuctures to achieve high scalability. The results of the square heat driven cavity test case are in good agreement with those reported earlier.

  4. Mass generation and the problem of seagull divergences

    CERN Document Server

    Figueiredo, C T

    2016-01-01

    The gluon mass generation is a purely non-perturbative effect, and the natural framework to study it in the continuum are the Schwinger-Dyson equations (SDEs) of the theory. At the level of the SDEs the generation of such a mass is associated with the existence of infrared finite solutions for the gluon propagator. From the theoretical point of view, the dynamical gluon mass generation has been traditionally plagued with seagull divergences. In this work, we will review how such divergences can be eliminated completely by virtue of a characteristic identity, valid in dimensional regularization. As a pedagogical example, we will first discuss in the context of scalar QED how it is possible to eliminate all seagull divergences, by triggering the aforementioned special identity, which enforces the masslessness of the photon. Then, we will discuss what happens in QCD and present an Ansatz for the three gluon vertex, which completely eliminates all seagull divergences and at same time allows for the possibility of...

  5. THE DIVERGENCE OF LAGRANGE INTERPOLATION FOR |x|α

    Institute of Scientific and Technical Information of China (English)

    Zhikang Lu; Xifang Ge

    2005-01-01

    This paper shows that the sequence of Lagrange interpolation polynomials corresponding to the function f(x) = |x|α(1 <α< 2) on [-1, 1] can diverge everywhere in the interval except at zero and the end-points.

  6. Constrained Transport vs. Divergence Cleanser Options in Astrophysical MHD Simulations

    Science.gov (United States)

    Lindner, Christopher C.; Fragile, P.

    2009-01-01

    In previous work, we presented results from global numerical simulations of the evolution of black hole accretion disks using the Cosmos++ GRMHD code. In those simulations we solved the magnetic induction equation using an advection-split form, which is known not to satisfy the divergence-free constraint. To minimize the build-up of divergence error, we used a hyperbolic cleanser function that simultaneously damped the error and propagated it off the grid. We have since found that this method produces qualitatively and quantitatively different behavior in high magnetic field regions than results published by other research groups, particularly in the evacuated funnels of black-hole accretion disks where Poynting-flux jets are reported to form. The main difference between our earlier work and that of our competitors is their use of constrained-transport schemes to preserve a divergence-free magnetic field. Therefore, to study these differences directly, we have implemented a constrained transport scheme into Cosmos++. Because Cosmos++ uses a zone-centered, finite-volume method, we can not use the traditional staggered-mesh constrained transport scheme of Evans & Hawley. Instead we must implement a more general scheme; we chose the Flux-CT scheme as described by Toth. Here we present comparisons of results using the divergence-cleanser and constrained transport options in Cosmos++.

  7. A highly divergent 33 kDa Cryptosporidium parvum antigen

    Science.gov (United States)

    Previous studies comparing the genome sequences of Cryptosporidium parvum with C. hominis identified a number of highly divergent genes that might reflect positive selection for host specificity. In the present study, a C. parvum sequence, namely cgd8-5370, whose amino acid sequence differs appreci...

  8. Divergent Thinking as an Indicator of Creative Potential

    Science.gov (United States)

    Runco, Mark A.; Acar, Selcuk

    2012-01-01

    Divergent thinking (DT) tests are very often used in creativity studies. Certainly DT does not guarantee actual creative achievement, but tests of DT are reliable and reasonably valid predictors of certain performance criteria. The validity of DT is described as reasonable because validity is not an all-or-nothing attribute, but is, instead, a…

  9. STUDIES ON GENETIC DIVERGENCE IN GOSSYPIUM ARBOREUM L.

    Directory of Open Access Journals (Sweden)

    Rumesh Ranjan

    2014-08-01

    Full Text Available On the basis of D2 values, sixty genotypes were grouped into eight clusters containing one to fourteen genotypes. These clusters consisted of genotypes with different geographical origins and indicated no correlation between genetic divergence and geographical divergence. The genotypes of Cluster VIII showed maximum genetic divergence with Cluster I and cluster V. The genotypes belonging to cluster VIII and cluster I may be selected for hybridization for generating genetic variability. Cluster VI having six genotypes was found to be best performing for agronomic characters followed by cluster VIII with one genotype and cluster V with eight genotypes. Thus to generate desirable genetic variability the crossing between cluster VI, VIII and V genotypes would be useful. It is suggested that hybridization among the genotypes of above said clusters would produce segregants for more than one economic character which can serve as parents of hybrids. Days to first flower followed by seed cotton yield per plant, number of monopods and plant height contribute maximum toward divergence.

  10. Ground state energies from converging and diverging power series expansions

    Science.gov (United States)

    Lisowski, C.; Norris, S.; Pelphrey, R.; Stefanovich, E.; Su, Q.; Grobe, R.

    2016-10-01

    It is often assumed that bound states of quantum mechanical systems are intrinsically non-perturbative in nature and therefore any power series expansion methods should be inapplicable to predict the energies for attractive potentials. However, if the spatial domain of the Schrödinger Hamiltonian for attractive one-dimensional potentials is confined to a finite length L, the usual Rayleigh-Schrödinger perturbation theory can converge rapidly and is perfectly accurate in the weak-binding region where the ground state's spatial extension is comparable to L. Once the binding strength is so strong that the ground state's extension is less than L, the power expansion becomes divergent, consistent with the expectation that bound states are non-perturbative. However, we propose a new truncated Borel-like summation technique that can recover the bound state energy from the diverging sum. We also show that perturbation theory becomes divergent in the vicinity of an avoided-level crossing. Here the same numerical summation technique can be applied to reproduce the energies from the diverging perturbative sums.

  11. Gauge-Invariance and Infrared Divergences in the Luminosity Distance

    CERN Document Server

    Biern, Sang Gyu

    2016-01-01

    Measurements of the luminosity distance have played a key role in discovering the late-time cosmic accel- eration. However, when accounting for inhomogeneities in the Universe, its interpretation has been plagued with infrared divergences in its theoretical predictions, which are in some cases used to explain the cosmic ac- celeration without dark energy. The divergences in most calculations are artificially removed by imposing an infrared cut-off scale. For the first time, we show that a gauge-invariant calculation of the luminosity distance is devoid of such divergences and consistent with the equivalence principle, eliminating the need to impose a cut-off scale. We present proper numerical calculations of the luminosity distance using the gauge-invariant expression and demonstrate that the numerical results with an ad hoc cut-off scale in previous calculations have negligible systematic errors as long as the cut-off scale is larger than the horizon scale. We discuss the origin of infrared divergences and t...

  12. Rates of genomic divergence in humans, chimpanzees and their lice.

    Science.gov (United States)

    Johnson, Kevin P; Allen, Julie M; Olds, Brett P; Mugisha, Lawrence; Reed, David L; Paige, Ken N; Pittendrigh, Barry R

    2014-02-22

    The rate of DNA mutation and divergence is highly variable across the tree of life. However, the reasons underlying this variation are not well understood. Comparing the rates of genetic changes between hosts and parasite lineages that diverged at the same time is one way to begin to understand differences in genetic mutation and substitution rates. Such studies have indicated that the rate of genetic divergence in parasites is often faster than that of their hosts when comparing single genes. However, the variation in this relative rate of molecular evolution across different genes in the genome is unknown. We compared the rate of DNA sequence divergence between humans, chimpanzees and their ectoparasitic lice for 1534 protein-coding genes across their genomes. The rate of DNA substitution in these orthologous genes was on average 14 times faster for lice than for humans and chimpanzees. In addition, these rates were positively correlated across genes. Because this correlation only occurred for substitutions that changed the amino acid, this pattern is probably produced by similar functional constraints across the same genes in humans, chimpanzees and their ectoparasites. PMID:24403325

  13. Play and Divergent Problem Solving: Evidence Supporting a Reciprocal Relationship.

    Science.gov (United States)

    Wyver, Shirley R.; Spence, Susan H.

    1999-01-01

    Three studies examined the relationship between specific forms of preschoolers' social and pretend play and divergent/convergent problem solving. Naturalistic and experimental designs were used to provide clearer account of relationship and to challenge assumption of single direction of influence. Results support complex reciprocal causality model…

  14. Divergent RNA transcription: a role in promoter unwinding?

    Science.gov (United States)

    Naughton, Catherine; Corless, Samuel; Gilbert, Nick

    2013-01-01

    New approaches using biotinylated-psoralen as a probe for investigating DNA structure have revealed new insights into the relationship between DNA supercoiling, transcription and chromatin compaction. We explore a hypothesis that divergent RNA transcription generates negative supercoiling at promoters facilitating initiation complex formation and subsequent promoter clearance.

  15. Stimulating Divergent Thinking in Junior High Career Education.

    Science.gov (United States)

    Ranke, Charlotte; Champoux, Ellen M.

    1981-01-01

    Describes a middle school career-oriented teaching unit with emphasis on teaching for divergent thinking. The unit provides hands-on opportunities for eighth-grade students to explore careers using the knowledge and skills developed in their home economics class. The careers are restaurant management, hospitality service, and interior design. (CT)

  16. Deep mtDNA divergences indicate cryptic species in a fig-pollinating wasp

    Directory of Open Access Journals (Sweden)

    Martin Joanne

    2006-10-01

    Full Text Available Abstract Background Figs and fig-pollinating wasps are obligate mutualists that have coevolved for ca 90 million years. They have radiated together, but do not show strict cospeciation. In particular, it is now clear that many fig species host two wasp species, so there is more wasp speciation than fig speciation. However, little is known about how fig wasps speciate. Results We studied variation in 71 fig-pollinating wasps from across the large geographic range of Ficus rubiginosa in Australia. All wasps sampled belong to one morphological species (Pleistodontes imperialis, but we found four deep mtDNA clades that differed from each other by 9–17% nucleotides. As these genetic distances exceed those normally found within species and overlap those (10–26% found between morphologically distinct Pleistodontes species, they strongly suggest cryptic fig wasp species. mtDNA clade diversity declines from all four present in Northern Queensland to just one in Sydney, near the southern range limit. However, at most sites multiple clades coexist and can be found in the same tree or even the same fig fruit and there is no evidence for parallel sub-division of the host fig species. Both mtDNA data and sequences from two nuclear genes support the monophyly of the "P. imperialis complex" relative to other Pleistodontes species, suggesting that fig wasp divergence has occurred without any host plant shift. Wasps in clade 3 were infected by a single strain (W1 of Wolbachia bacteria, while those in other clades carried a double infection (W2+W3 of two other strains. Conclusion Our study indicates that cryptic fig-pollinating wasp species have developed on a single host plant species, without the involvement of host plant shifts, or parallel host plant divergence. Despite extensive evidence for coevolution between figs and fig wasps, wasp speciation may not always be linked strongly with fig speciation.

  17. Sampling bacteria with a laser

    Science.gov (United States)

    Schwarzwälder, Kordula; Rutschmann, Peter

    2014-05-01

    Water quality is a topic of high interest and it's getting more and more important due to climate change and the implementation of European Water Framework Directive (WFD). One point of interest here is the inflow of bacteria into a river caused by combined sewer overflows which lead untreated wastewater including bacteria directly into a river. These bacteria remain in the river for a certain time, they settle down and can be remobilised again. In our study we want to investigate these processes of sedimentation and resuspension and use the results for the development of a software module coupled with the software Flow3D. Thereby we should be able to simulate and therefore predict the water quality influenced by combined sewer overflows. Hence we need to get information about the bacteria transport and fate. We need to know about the size of the bacteria or of the bacteria clumps and the size of the particles the bacteria are attached to. The agglomerates lead to different characteristics and velocities of settlement. The timespan during this bacteria can be detected in the bulk phase depends on many factors like the intensity of UV light, turbidity of the water, the temperature of the water, if there are grazers and a lot more. The size, density and composition of the agglomerates is just a part of all these influencing factors, but it is extremely difficult to differ between the other effects if we have no information about the simple sedimentation in default of these basic information. However we have a big problem getting the data. The chaining between bacteria or bacteria and particles is not too strong, so filtering the water to get a sieving curve may destroy these connections. We did some experiments similar to PIV (particle image velocimetry) measurements and evaluated the pictures with a macro written for the software ImageJ. Doing so we were able to get the concentration of bacteria in the water and collect information about the size of the bacteria. We

  18. An oral recombinant Salmonella enterica serovar Typhimurium mutant elicits systemic antigen-specific CD8+ T cell cytokine responses in mice

    Directory of Open Access Journals (Sweden)

    Chin'ombe Nyasha

    2009-04-01

    Full Text Available Abstract Background The induction of antigen-specific CD8+ T cell cytokine responses against an attenuated, oral recombinant Salmonella enterica serovar Typhimurium vaccine expressing a green fluorescent protein (GFP model antigen was investigated. A GFP expression plasmid was constructed in which the gfp gene was fused in-frame with the 5' domain of the Escherichia coli β-galactosidase α-gene fragment with expression under the lac promoter. Groups of mice were orally immunized three times with the bacteria and systemic CD8+ T cell cytokine responses were evaluated. Results High level of the GFP model antigen was expressed by the recombinant Salmonella vaccine vector. Systemic GFP-specific CD8+ T cell cytokine (IFN-γ and IL-4 immune responses were detected after mice were orally vaccinated with the bacteria. It was shown that 226 net IFN-γ and 132 net IL-4 GFP-specific SFUs/10e6 splenocytes were formed in an ELISPOT assay. The level of IFN-γ produced by GFP peptide-stimulated cells was 65.2-fold above background (p Conclusion These results suggested that a high expressing recombinant Salmonella vaccine given orally to mice would elicit antigen-specific CD8+ T cell responses in the spleen. Salmonella bacteria may, therefore, be used as potential mucosal vaccine vectors.

  19. Beer spoilage bacteria and hop resistance

    NARCIS (Netherlands)

    Sakamoto, K; Konings, WN

    2003-01-01

    For brewing industry, beer spoilage bacteria have been problematic for centuries. They include some lactic acid bacteria such as Lactobacillus brevis, Lactobacillus lindneri and Pediococcus damnosus, and some Gram-negative bacteria such as Pectinatus cerevisiiphilus, Pectinatus frisingensis and Mega

  20. On Unified Generalizations of Relative Jensen--Shannon and Arithmetic--Geometric Divergence Measures, and Their Properties

    OpenAIRE

    Kumar, Pranesh; Taneja, Inder Jeet

    2005-01-01

    In this paper we shall consider one parametric generalization of some non-symmetric divergence measures. The \\textit{non-symmetric divergence measures} are such as: Kullback-Leibler \\textit{relative information}, $\\chi ^2-$\\textit{divergence}, \\textit{relative J -- divergence}, \\textit{relative Jensen -- Shannon divergence} and \\textit{relative Arithmetic -- Geometric divergence}. All the generalizations considered can be written as particular cases of Csisz\\'{a}r's \\textit{f-divergence}. By ...

  1. Antimicrobial Effect of Lactic Acid Bacteria against Common Pathogenic Bacteria

    Directory of Open Access Journals (Sweden)

    Mohammad Mohammaddoost Chakoosari ( Msc

    2016-01-01

    Full Text Available Background and Objective: Probiotics are living microorganisms that have beneficial effects on the health of digestive system. The aim of this study was to evaluate the antimicrobial ability of acidic and neutral supernatants (culture supernatant of lactic acid bacteria against common bacterial pathogens. Methods: Four species of lactic acid bacteria (Lactobacillus plantarum PTCC1745, Lactobacillus PTCC1608, Lactobacillus Saki PTCC1712 and Lactobacillus Lactis PTCC1336 were obtained from the microbial collection of Iranian Research Organization for Science and Technology in Lyophilized form. The antimicrobial activity of neutral and acidic supernatants against bacterial pathogens was investigated using the Disk and Well Diffusion Agar methods. Results: Lactic acid bacteria showed good antimicrobial ability against six pathogenic bacteria with the highest inhibitory effect observed in Lactococcus lactis against E. coli PTCC1399 through well method with an average diameter of 14 mm inhibition zone. In this study, the well diffusion method was far more sensitive compared to the disk method and acidic supernatants showed higher antimicrobial efficiency compared to neutral types. Conclusion: the Metabolites produced by lactic acid bacteria are able to inhibit the growth of pathogenic bacteria that can be an important and practical solution for the prevention and treatment of infections and ultimately improve human health. Keywords: Lactobacillus; Lactococcus; Probiotic; Antibacterial

  2. Impaired cardiovascular function caused by different stressors elicits a common pathological and transcriptional response in zebrafish embryos.

    Science.gov (United States)

    Chen, Jing

    2013-09-01

    Zebrafish embryos have been widely used to study the genes and processes needed for normal vertebrate heart development. We recently observed that exposure to 2,3,7,8-tetra-chlorodibenzo-p-dioxin (TCDD) or retinoic acid (RA) produces very similar signs of heart failure in developing zebrafish via divergent molecular pathways. The fact that diverse stressors and mutations cause severe pericardial edema and circulatory collapse in developing zebrafish has been largely unexplored. We hypothesized that unrelated chemicals can trigger a common pathological response leading to the same end-stage heart failure. To test this hypothesis, we compared the effects of TCDD, RA, carbaryl, valproic acid, and morpholino oligonucleotide (MO) knockdown of TBX5 on the developing heart in zebrafish embryos. These model stressors have all been previously reported to affect zebrafish heart development, and elicited very similar signs of embryonic heart failure. Microarray analysis showed that one cluster of 92 transcripts affected by these different treatments was significantly downregulated by all treatments. This gene cluster is composed of transcripts required for chromosome assembly, DNA replication, and cell cycle progression. We refer to this cluster as the cell cycle gene cluster (CCGC). Immunohistochemistry revealed that downregulation of the CCGC precedes a halt in cardiomyocyte proliferation in the hearts of zebrafish exposed to any of the treatments. Previous work has shown that the initial response to TCDD is a decrease in cardiac output. Since this precedes the signs of edema, heart failure, and fall in CCGC expression, we postulated that any factor that decreases cardiac output will produce the same syndrome of heart failure responses. To test this, we used MO knockdown of cardiac troponin T2 (TNNT2) to specifically block contractility. The TNNT2-MO produced exactly the same signs of cardiotoxicity as the other treatments, including downregulation of the signature CCGC

  3. Mitochondrial divergence between slow- and fast-aging garter snakes.

    Science.gov (United States)

    Schwartz, Tonia S; Arendsee, Zebulun W; Bronikowski, Anne M

    2015-11-01

    Mitochondrial function has long been hypothesized to be intimately involved in aging processes--either directly through declining efficiency of mitochondrial respiration and ATP production with advancing age, or indirectly, e.g., through increased mitochondrial production of damaging free radicals with age. Yet we lack a comprehensive understanding of the evolution of mitochondrial genotypes and phenotypes across diverse animal models, particularly in species that have extremely labile physiology. Here, we measure mitochondrial genome-types and transcription in ecotypes of garter snakes (Thamnophis elegans) that are adapted to disparate habitats and have diverged in aging rates and lifespans despite residing in close proximity. Using two RNA-seq datasets, we (1) reconstruct the garter snake mitochondrial genome sequence and bioinformatically identify regulatory elements, (2) test for divergence of mitochondrial gene expression between the ecotypes and in response to heat stress, and (3) test for sequence divergence in mitochondrial protein-coding regions in these slow-aging (SA) and fast-aging (FA) naturally occurring ecotypes. At the nucleotide sequence level, we confirmed two (duplicated) mitochondrial control regions one of which contains a glucocorticoid response element (GRE). Gene expression of protein-coding genes was higher in FA snakes relative to SA snakes for most genes, but was neither affected by heat stress nor an interaction between heat stress and ecotype. SA and FA ecotypes had unique mitochondrial haplotypes with amino acid substitutions in both CYTB and ND5. The CYTB amino acid change (Isoleucine → Threonine) was highly segregated between ecotypes. This divergence of mitochondrial haplotypes between SA and FA snakes contrasts with nuclear gene-flow estimates, but correlates with previously reported divergence in mitochondrial function (mitochondrial oxygen consumption, ATP production, and reactive oxygen species consequences).

  4. Screening of aspartate dehydrogenase of bacteria

    OpenAIRE

    Fukuda, Shoko; Okamura, Tokumitsu; Yasumasa, Izumi; Takeno, Tomomi; Ohsugi, Masahiro

    2001-01-01

    Fifty-two strains of bacteria cultured under aerobic conditions and 12 strains of bacteria cultured under anaerobic conditions demonstrated high activity staining of aspartate dehydrogenase with NAD^+. Four strains of bacteria cultured under aerobic conditions and 7 strains of bacteria cultured under anaerobic conditions demonstrated high activity staining of aspartate dehydrogenase with NADP^+. Seven strains of bacteria cultured under aerobic conditions and 4 strains of bacteria cultured und...

  5. Population genomics of early events in the ecological differentiation of bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, Jesse B. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Broad Inst., Cambridge, MA (United States); Friedman, Jonatan [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Cordero, Otto X. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Preheim, Sarah P.. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Timberlake, Sonia C. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Szabo, Gitta [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Polz, Martin F. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Alm, Eric J. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Broad Inst., Cambridge, MA (United States)

    2012-04-06

    Genetic exchange is common among bacteria, but its effect on population diversity during ecological differentiation remains controversial. A fundamental question is whether advantageous mutations lead to selection of clonal genomes or, as in sexual eukaryotes, sweep through populations on their own. Here, we show that in two recently diverged populations of ocean bacteria, ecological differentiation has occurred akin to a sexual mechanism: A few genome regions have swept through subpopulations in a habitat-specific manner, accompanied by gradual separation of gene pools as evidenced by increased habitat specificity of the most recent recombinations. These findings reconcile previous, seemingly contradictory empirical observations of the genetic structure of bacterial populations and point to a more unified process of differentiation in bacteria and sexual eukaryotes than previously thought.

  6. Bacteria, fungi and protozoa paper

    Data.gov (United States)

    U.S. Environmental Protection Agency — Bacteria and fungi in source and treated drinking water This dataset is associated with the following publication: King , D., S. Pfaller , M. Donohue , S. Vesper ,...

  7. Adherention ability of intestinal bacteria

    OpenAIRE

    Morgensternová, Tereza

    2014-01-01

    Probiotics are live microorganisms that provide positive health benefits. Bacteria of the genus Bifidobacterium belong to this group. These bacteria have to meet a number of criteria so that they could be considered for probiotic. These include the ability to survive, grow, and be metabolically active in the gastrointestinal tract of the recipient. Probiotics protect the intestinal mucus from the adhesion of pathogenic organisms. The aim of this thesis was to test the ability of different ...

  8. Thymidine kinase diversity in bacteria

    DEFF Research Database (Denmark)

    Sandrini, Michael; Clausen, A.R.; Munch-Petersen, B.;

    2006-01-01

    Thymidine kinases (TKs) appear to be almost ubiquitous and are found in nearly all prokaryotes, eukaryotes, and several viruses. They are the key enzymes in thymidine salvage and activation of several anti-cancer and antiviral drugs. We show that bacterial TKs can be subdivided into 2 groups. The....... The TKs from Gram-positive bacteria are more closely related to the eukaryotic TK1 enzymes than are TKs from Gram-negative bacteria....

  9. A comparative effect of 3 disinfectants on heterotrophic bacteria, iron bacteria and sulfate-reducing bacteria

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The disinfection effect of chlorine dioxide, chlorine and their mixture on heterotrophic bacteria, iron bacteria and sulfate-reducing bacteria in circulating cooling water was studied. The results of the test indicated that high purity chlorine dioxide was the most effective biocide in the 3 disinfectants, and with a dosage of 0.5mg/L, chlorine dioxide could obtain perfect effect. High purity chloride dioxide could have the excellent effect with the pH value of 6 to 10, and could keep it within 72 h. Chlorine and their mixture couldn't reach the effect of chlorine dioxide.

  10. Bioreporter bacteria for landmine detection

    Energy Technology Data Exchange (ETDEWEB)

    Burlage, R.S. [Oak Ridge National Lab., TN (United States); Youngblood, T. [Frisby Technologies, Aiken, SC (United States); Lamothe, D. [American Technologies, Inc., Huntsville, AL (United States). Ordnance/Explosives Environmental Services Div.

    1998-04-01

    Landmines (and other UXO) gradually leak explosive chemicals into the soil at significant concentrations. Bacteria, which have adapted to scavenge low concentrations of nutrients, can detect these explosive chemicals. Uptake of these chemicals results in the triggering of specific bacterial genes. The authors have created genetically recombinant bioreporter bacteria that detect small concentrations of energetic chemicals. These bacteria are genetically engineered to produce a bioluminescent signal when they contact specific explosives. A gene for a brightly fluorescent compound can be substituted for increased sensitivity. By finding the fluorescent bacteria, you find the landmine. Detection might be accomplished using stand-off illumination of the minefield and GPS technology, which would result in greatly reduced risk to the deminers. Bioreporter technology has been proven at the laboratory scale, and will be tested under field conditions in the near future. They have created a bacterial strain that detects sub-micromolar concentrations of o- and p-nitrotoluene. Related bacterial strains were produced using standard laboratory protocols, and bioreporters of dinitrotoluene and trinitrotoluene were produced, screening for activity with the explosive compounds. Response time is dependent on the growth rate of the bacteria. Although frill signal production may require several hours, the bacteria can be applied over vast areas and scanned quickly, producing an equivalent detection speed that is very fast. This technology may be applicable to other needs, such as locating buried explosives at military and ordnance/explosive manufacturing facilities.

  11. Divergência genética em linhagens de melancia Genetic divergence in watermelon lines

    Directory of Open Access Journals (Sweden)

    Flávio de França Souza

    2005-06-01

    Full Text Available A divergência genética entre 31 genótipos de melancia foi avaliada por meio da análise de variáveis canônicas e de técnicas de agrupamento (Tocher e método hierárquico de Ward baseadas na distância generalizada de Mahalanobis (D²ii'. Trinta linhagens, obtidas a partir de acessos coletados no Nordeste brasileiro e a cultivar 'Crimson Sweet' foram avaliadas quanto ao número de dias para o aparecimento da primeira flor masculina e da primeira flor feminina (NDM e NDF; número do nó da primeira flor masculina e da primeira flor feminina (NGM e NGF; número de frutos por planta (NFP; comprimento de rama principal (CRP; peso médio de fruto (PMF; teor de sólidos solúveis (TSS; diâmetro transversal e longitudinal do fruto (DTF e DLF e espessura média de casca (EMC. O experimento foi realizado em delineamento de blocos ao acaso com três repetições, compostas por parcelas de sete plantas. As características que mais contribuíram para a divergência entre as linhagens foram número de frutos por planta, diâmetro longitudinal, teor de sólidos solúveis e peso médio de fruto. Foram formados três grupos por meio do método de otimização de Tocher, três por meio do método hierárquico de Ward e quatro grupos pela dispersão gráfica baseada nas duas primeiras variáveis canônicas. Neste caso, o grupo I compôs-se de sete linhagens de Pernambuco e uma da Bahia; o grupo II reuniu todas as 21 linhagens do Maranhão; os grupos III e IV foram compostos pela linhagem 97-0247.008 (Pernambuco e pela cultivar Crimson Sweet, respectivamente. As linhagens 87-019.021 e 87-019.022 foram as mais semelhantes, enquanto a linhagem 87-019.023 e 'Crimson Sweet' apresentaram maior dissimilaridade pela distância generalizada Mahalanobis (D²ii'. Os cruzamentos mais promissores serão aqueles realizados entre Crimson Sweet e as linhagens do grupo II. Cruzamentos entre Crimson Sweet e as linhagens do grupo I serão interessantes para a obtenção de

  12. Diversity of extremophilic purple phototrophic bacteria in Soap Lake, a Central Washington (USA) Soda Lake.

    Science.gov (United States)

    Asao, Marie; Pinkart, Holly C; Madigan, Michael T

    2011-08-01

    Culture-based and culture-independent methods were used to explore the diversity of phototrophic purple bacteria in Soap Lake, a small meromictic soda lake in the western USA. Among soda lakes, Soap Lake is unusual because it consists of distinct upper and lower water bodies of vastly different salinities, and its deep waters contain up to 175 mM sulfide. From Soap Lake water new alkaliphilic purple sulfur bacteria of the families Chromatiaceae and Ectothiorhodospiraceae were cultured, and one purple non-sulfur bacterium was isolated. Comparative sequence analysis of pufM, a gene that encodes a key photosynthetic reaction centre protein universally found in purple bacteria, was used to measure the diversity of purple bacteria in Soap Lake. Denaturing gradient gel electrophoresis and subsequent phylogenetic analyses of pufMs amplified from Soap Lake water revealed that a significant diversity of purple bacteria inhabit this soda lake. Although close relatives of several of the pufM phylotypes obtained from cultured species could also be detected in Soap Lake water, several other more divergent pufM phylotypes were also detected. It is possible that Soap Lake purple bacteria are major contributors of organic matter into the ecosystem of this lake, especially in its extensive anoxic and sulfidic deep waters. PMID:21410624

  13. Isolation and Identification of Concrete Environment Bacteria

    Science.gov (United States)

    Irwan, J. M.; Anneza, L. H.; Othman, N.; Husnul, T.; Alshalif, A. F.

    2016-07-01

    This paper presents the isolation and molecular method for bacteria identification through PCR and DNA sequencing. Identification of the bacteria species is required in order to fully utilize the bacterium capability for precipitation of calcium carbonate in concrete. This process is to enable the addition of suitable catalyst according to the bacterium enzymatic pathway that is known through the bacteria species used. The objective of this study is to isolate, enriched and identify the bacteria species. The bacteria in this study was isolated from fresh urine and acid mine drainage water, Kota Tinggi, Johor. Enrichment of the isolated bacteria was conducted to ensure the bacteria survivability in concrete. The identification of bacteria species was done through polymerase chain reaction (PCR) and rRDNA sequencing. The isolation and enrichment of the bacteria was done successfully. Whereas, the results for bacteria identification showed that the isolated bacteria strains are Bacillus sp and Enterococus faecalis.

  14. Divergent series, summability and resurgence II simple and multiple summability

    CERN Document Server

    Loday-Richaud, Michèle

    2016-01-01

    Addressing the question how to “sum” a power series in one variable when it diverges, that is, how to attach to it analytic functions, the volume gives answers by presenting and comparing the various theories of k-summability and multisummability. These theories apply in particular to all solutions of ordinary differential equations. The volume includes applications, examples and revisits, from a cohomological point of view, the group of tangent-to-identity germs of diffeomorphisms of C studied in volume 1. With a view to applying the theories to solutions of differential equations, a detailed survey of linear ordinary differential equations is provided which includes Gevrey asymptotic expansions, Newton polygons, index theorems and Sibuya’s proof of the meromorphic classification theorem that characterizes the Stokes phenomenon for linear differential equations. This volume is the second of a series of three entitled Divergent Series, Summability and Resurgence. It is aimed at graduate students and res...

  15. Evolutionary divergency of giant tortoises in Gal?pagos

    Science.gov (United States)

    Fritts, T.H.

    1984-01-01

    The giant tortoises in the Galapagos Archipelago diverge considerably in size, and in shape and other carapace characteristics. The saddleback morphotype is known only from insular faunas lacking large terrestrial predators (i.e. Galapagos and Mauritius) and in Galapagos is associated with xeric habitats where vertical feeding range and vertical reach in agonistic encounters are adaptive. The large domed morphotype is associated with relatively cool, mesic habitats where intraspecific competition for food and other resources may be less intense than in xeric habitats. Other external characteristics that differ between tortoise populations are also correlated with ecological variation. Tortoises have radiated into a mosaic of ecological conditions in the Galapagos but critical data are lacking on the role of genetic and environmental controls on phenotypic variation. Morphological divergence in tortoises is potentially a better indicator of present ecological conditions than of evolutionary relationships.

  16. The $\\Omega$ dependence of the velocity divergence distribution

    CERN Document Server

    Bernardeau, F; Hivon, E; Bouchet, F R

    1996-01-01

    We present a series of results investigating the $\\Omega$ dependence of the distribution function of the large scale local cosmic velocity divergence. Analytical studies using perturbation theory techniques indicate that the shape of this distribution should be strongly dependent on $\\Omega$. This dependence is all the more interesting as it does not involve biases of the galaxy distribution with respect to the underlying density distribution, making it a potentially promising and useful basis for new and alternative methods to obtain bias-independent estimates of $\\Omega$. After a description of the $\\Omega$ dependent characteristics expected in the shape of the velocity divergence PDF, we study this distribution on the basis of a set of $N$-body simulations. To analyze the discretely sampled velocity field yielded by the latter, we apply a set of recently developed numerical tools, the ``Voronoi'' and ``Delaunay'' methods. These two methods were devised specifically for the purpose of investigating statisti...

  17. Perturbation Theory in Supersymmetric QED: Infrared Divergences and Gauge Invariance

    CERN Document Server

    Dine, Michael; Haber, Howard E; Haskins, Laurel Stephenson

    2016-01-01

    We study some aspects of perturbation theory in $N=1$ supersymmetric abelian gauge theories with massive charged matter. In general gauges, infrared (IR) divergences and nonlocal behavior arise in 1PI diagrams, associated with a $1/k^4$ term in the propagator for the vector superfield. We examine this structure in supersymmetric QED. The IR divergences are gauge-dependent and must cancel in physical quantities like the electron pole mass. We demonstrate that cancellation takes place in a nontrivial way, amounting to a reorganization of the perturbative series from powers of $e^2$ to powers of $e$. We also show how these complications are avoided in cases where a Wilsonian effective action can be defined.

  18. Blind Deconvolution of Seismic Data Using f-Divergences

    Directory of Open Access Journals (Sweden)

    Bing Zhang

    2011-09-01

    Full Text Available This paper proposes a new approach to the seismic blind deconvolution problem in the case of band-limited seismic data characterized by low dominant frequency and short data records, based on Csiszár’s f-divergence. In order to model the probability density function of the deconvolved data, and obtain the closed form formula of Csiszár’s f-divergence, mixture Jones’ family of distributions (MJ is introduced, by which a new criterion for blind deconvolution is constructed. By applying Neidell’s wavelet model to the inverse filter, we then make the optimization program for multivariate reduce to univariate case. Examples are provided showing the good performance of the method, even in low SNR situations.

  19. Genetic Divergence and Dispersal of Yellow Fever Virus, Brazil

    Science.gov (United States)

    Bryant, Juliet E.; Travassos da Rosa, Amelia P.A.; Tesh, Robert B.; Rodrigues, Sueli G.; Barrett, Alan D.T.

    2004-01-01

    An analysis of 79 yellow fever virus (YFV) isolates collected from 1935 to 2001 in Brazil showed a single genotype (South America I) circulating in the country, with the exception of a single strain from Rondônia, which represented South America genotype II. Brazilian YFV strains have diverged into two clades; an older clade appears to have become extinct and another has become the dominant lineage in recent years. Pairwise nucleotide diversity between strains ranged from 0% to 7.4%, while amino acid divergence ranged from 0% to 4.6%. Phylogenetic analysis indicated traffic of virus variants through large geographic areas and suggested that migration of infected people may be an important mechanism of virus dispersal. Isolation of vaccine virus from a patient with a fatal case suggests that vaccine-related illness may have been misdiagnosed in the past. PMID:15498159

  20. A divergence-cleaning scheme for cosmological SPMHD simulations

    CERN Document Server

    Stasyszyn, F A; Beck, A M

    2012-01-01

    In magnetohydrodynamics (MHD), the magnetic field is evolved by the induction equation and coupled to the gas dynamics by the Lorentz force. We perform numerical smoothed particle magnetohydrodynamics (Spmhd) simulations and study the influence of a numerical magnetic divergence. For instabilities arising from divergence B related errors, we find the hyperbolic/parabolic cleaning scheme suggested by Dedner et al. 2002 to give good results and prevent numerical artifacts from growing. Additionally, we demonstrate that certain current Spmhd implementations of magnetic field regularizations give rise to unphysical instabilities in long-time simulations. We also find this effect when employing Euler potentials (divergenceless by definition), which are not able to follow the winding-up process of magnetic field lines properly. Furthermore, we present cosmological simulations of galaxy cluster formation at extremely high resolution including the evolution of magnetic fields. We show synthetic Faraday rotation maps ...

  1. Divergence-free MHD Simulations with the HERACLES Code

    Directory of Open Access Journals (Sweden)

    Vides J.

    2013-12-01

    Full Text Available Numerical simulations of the magnetohydrodynamics (MHD equations have played a significant role in plasma research over the years. The need of obtaining physical and stable solutions to these equations has led to the development of several schemes, all requiring to satisfy and preserve the divergence constraint of the magnetic field numerically. In this paper, we aim to show the importance of maintaining this constraint numerically. We investigate in particular the hyperbolic divergence cleaning technique applied to the ideal MHD equations on a collocated grid and compare it to the constrained transport technique that uses a staggered grid to maintain the property. The methods are implemented in the software HERACLES and several numerical tests are presented, where the robustness and accuracy of the different schemes can be directly compared.

  2. Content-based network model with duplication and divergence

    Science.gov (United States)

    Şengün, Yasemin; Erzan, Ayşe

    2006-06-01

    We construct a minimal content-based realization of the duplication and divergence model of genomic networks introduced by Wagner [Proc. Natl. Acad. Sci. 91 (1994) 4387] and investigate the scaling properties of the directed degree distribution and clustering coefficient. We find that the content-based network exhibits crossover between two scaling regimes, with log-periodic oscillations for large degrees. These features are not present in the original gene duplication model, but inherent in the content-based model of Balcan and Erzan. The scaling form of the degree distribution of the content-based model turns out to be robust under duplication and divergence, with some re-adjustment of the scaling exponents, while the out-clustering coefficient goes over from a weak power-law dependence on the degree, to an exponential decay under mutations which include splitting and merging of strings.

  3. Stable divergence angles of a magnetic dipole spiral array

    Energy Technology Data Exchange (ETDEWEB)

    Fan, X.D.; Bursill, L.A.

    1996-03-01

    An analytical model is introduced for Douady and Couder`s [1992] experiment, where phyllotactic patterns appear as a dynamical result of the interaction between magnetic dipoles. The difference equation for the divergence angle (i.e. the angle between successive radial vectors) is obtained by solving the equations of motion with a second nearest neighbour (SNN) approximation. A one dimensional map analysis as well as a comprehensive analytical proof shows that the divergence angle always converges to a single attractor regardless of the initial conditions. This attractor is approximately the Fibonacci angle ({approx} 138 deg) within variations due to a growth factor {mu} of the pattern. The system is proved to be stable with the SNN approximation. Further analysis with a third nearest neighbour approximation (TNN) shows extra linearly stable attractors may appear around the Lucas angle at {approx} 99.5 deg. 7 refs., 5 figs.

  4. Immunization with Brucella VirB proteins reduces organ colonization in mice through a Th1-type immune response and elicits a similar immune response in dogs.

    Science.gov (United States)

    Pollak, Cora N; Wanke, María Magdalena; Estein, Silvia M; Delpino, M Victoria; Monachesi, Norma E; Comercio, Elida A; Fossati, Carlos A; Baldi, Pablo C

    2015-03-01

    VirB proteins from Brucella spp. constitute the type IV secretion system, a key virulence factor mediating the intracellular survival of these bacteria. Here, we assessed whether a Th1-type immune response against VirB proteins may protect mice from Brucella infection and whether this response can be induced in the dog, a natural host for Brucella. Splenocytes from mice immunized with VirB7 or VirB9 responded to their respective antigens with significant and specific production of gamma interferon (IFN-γ), whereas interleukin-4 (IL-4) was not detected. Thirty days after an intraperitoneal challenge with live Brucella abortus, the spleen load of bacteria was almost 1 log lower in mice immunized with VirB proteins than in unvaccinated animals. As colonization reduction seemed to correlate with a Th1-type immune response against VirB proteins, we decided to assess whether such a response could be elicited in the dog. Peripheral blood mononuclear cells (PBMCs) from dogs immunized with VirB proteins (three subcutaneous doses in QuilA adjuvant) produced significantly higher levels of IFN-γ than cells from control animals upon in vitro stimulation with VirB proteins. A skin test to assess specific delayed-type hypersensitivity was positive in 4 out of 5 dogs immunized with either VirB7 or VirB9. As both proteins are predicted to locate in the outer membrane of Brucella organisms, the ability of anti-VirB antibodies to mediate complement-dependent bacteriolysis of B. canis was assessed in vitro. Sera from dogs immunized with either VirB7 or VirB9, but not from those receiving phosphate-buffered saline (PBS), produced significant bacteriolysis. These results suggest that VirB-specific responses that reduce organ colonization by Brucella in mice can be also elicited in dogs.

  5. Immunization with Brucella VirB proteins reduces organ colonization in mice through a Th1-type immune response and elicits a similar immune response in dogs.

    Science.gov (United States)

    Pollak, Cora N; Wanke, María Magdalena; Estein, Silvia M; Delpino, M Victoria; Monachesi, Norma E; Comercio, Elida A; Fossati, Carlos A; Baldi, Pablo C

    2015-03-01

    VirB proteins from Brucella spp. constitute the type IV secretion system, a key virulence factor mediating the intracellular survival of these bacteria. Here, we assessed whether a Th1-type immune response against VirB proteins may protect mice from Brucella infection and whether this response can be induced in the dog, a natural host for Brucella. Splenocytes from mice immunized with VirB7 or VirB9 responded to their respective antigens with significant and specific production of gamma interferon (IFN-γ), whereas interleukin-4 (IL-4) was not detected. Thirty days after an intraperitoneal challenge with live Brucella abortus, the spleen load of bacteria was almost 1 log lower in mice immunized with VirB proteins than in unvaccinated animals. As colonization reduction seemed to correlate with a Th1-type immune response against VirB proteins, we decided to assess whether such a response could be elicited in the dog. Peripheral blood mononuclear cells (PBMCs) from dogs immunized with VirB proteins (three subcutaneous doses in QuilA adjuvant) produced significantly higher levels of IFN-γ than cells from control animals upon in vitro stimulation with VirB proteins. A skin test to assess specific delayed-type hypersensitivity was positive in 4 out of 5 dogs immunized with either VirB7 or VirB9. As both proteins are predicted to locate in the outer membrane of Brucella organisms, the ability of anti-VirB antibodies to mediate complement-dependent bacteriolysis of B. canis was assessed in vitro. Sera from dogs immunized with either VirB7 or VirB9, but not from those receiving phosphate-buffered saline (PBS), produced significant bacteriolysis. These results suggest that VirB-specific responses that reduce organ colonization by Brucella in mice can be also elicited in dogs. PMID:25540276

  6. The use of expert elicitation in environmental health impact assessment: a seven step procedure

    Directory of Open Access Journals (Sweden)

    van der Sluijs Jeroen P

    2010-04-01

    Full Text Available Abstract Background Environmental health impact assessments often have to deal with substantial uncertainties. Typically, the knowledge-base is limited with incomplete, or inconsistent evidence and missing or ambiguous data. Consulting experts can help to identify and address uncertainties. Methods Formal expert elicitation is a structured approach to systematically consult experts on uncertain issues. It is most often used to quantify ranges for poorly known parameters, but may also be useful to further develop qualitative issues such as definitions, assumptions or conceptual (causal models. A thorough preparation and systematic design and execution of an expert elicitation process may increase the validity of its outcomes and transparency and trustworthiness of its conclusions. Various expert elicitation protocols and methods exist. However, these are often not universally applicable, and need customization to suite the needs of a specific study. In this paper, we set out to develop a widely applicable method for the use of expert elicitation in environmental health impact assessment. Results We present a practical yet flexible seven step procedure towards organising expert elicitation in the context of environmental health impact assessment, based on existing protocols. We describe how customization for specific applications is always necessary. In particular, three issues affect the choice of methods for a particular application: the types of uncertainties considered, the intended use of the elicited information, and the available resources. We outline how these three considerations guide choices regarding the design and execution of expert elicitation. We present signposts to sources where the issues are discussed in more depth to give the newcomer the insights needed to make the protocol work. The seven step procedure is illustrated using examples from earlier published elicitations in the field of environmental health research

  7. Distance-dependent patterns of molecular divergences in tuatara mitogenomes

    OpenAIRE

    Subramanian, Sankar; Mohandesan, Elmira; Millar, Craig D; David M Lambert

    2015-01-01

    Population genetic models predict that populations that are geographically close to each other are expected to be genetically more similar to each other compared to those that are widely separate. However the patterns of relationships between geographic distance and molecular divergences at neutral and constrained regions of the genome are unclear. We attempted to clarify this relationship by sequencing complete mitochondrial genomes of the relic species Tuatara (Sphenodon punctatus) from ten...

  8. Compulsory education - in schools only? : divergent developments in Germany

    OpenAIRE

    Schirrmacher, Thomas

    2012-01-01

    Germany is the focus of this paper, owing to the fact that since 1938 it has had the strictest laws on compulsory schooling worldwide. As a result, homeschooling in Germany has become virtually impossible. There are interesting divergences between policy and practice in the German setting, both in the country’s educational history and present educational problems. The Länder (federal states) have the responsibility for education, and they are taking a much stricter line against homeschoolers ...

  9. Divergence via Abstraction' Practices for Inventing New Puzzles

    OpenAIRE

    Sugiyama, Kozo; Maeda, Atsuhiko; Mizumoto, Akinori

    2003-01-01

    To invent new puzzles, we take a systematic approach called divergence via abstraction. Existing popular puzzles called permutation puzzles and cyclic puzzles are abstracted and converted into other media such as graphs, blocks, sounds, and robots, while preserving their logic. We implement puzzle generators on different media and variations of generated puzzles are shown. Merits and demerits of new puzzles are evaluated comparing with the original puzzles. This systematic approach can flexib...

  10. Investigating the interaction between schizotypy, divergent thinking and cannabis use

    OpenAIRE

    Schafer, G.; Feilding, A.; Morgan, C J; Agathangelou, M.; Freeman, T P; Valerie Curran, H.

    2012-01-01

    Cannabis acutely increases schizotypy and chronic use is associated with elevated rates of psychosis. Creative individuals have higher levels of schizotypy, however links between cannabis use, schizotypy and creativity have not been investigated. We investigated the effects of cannabis smoked naturalistically on schizotypy and divergent thinking, a measure of creativity. One hundred and sixty cannabis users were tested on 1 day when sober and another day when intoxicated with cannabis. State ...

  11. Divergence and convergence in early embryonic stages of metazoans

    OpenAIRE

    Galis, Frietson; Sinervo, Barry

    2002-01-01

    The early stages of organogenesis in metazoans differ drastically between higher order taxa such as phyla and classes. The segmented germ band stage in insects, the nauplius stage of crustaceans, and the neurula/pharyngula stage in vertebrates are examples of this diversification. In striking contrast with this divergence, is the similarity of these stages within these taxa, i.e., within insects, crustaceans, and vertebrates. The early stages of organogenesis, or phylotypic stages, have, thus...

  12. Reconciling divergent estimates of oil and gas methane emissions

    OpenAIRE

    Zavala-Araiza, Daniel; Lyon, David R; Alvarez, Ramón A.; Davis, Kenneth J.; Harriss, Robert; Herndon, Scott C.; Karion, Anna; Kort, Eric Adam; Lamb, Brian K.; Lan, Xin; Marchese, Anthony J.; Pacala, Stephen W.; Robinson, Allen L.; Shepson, Paul B.; Sweeney, Colm

    2015-01-01

    Past studies reporting divergent estimates of methane emissions from the natural gas supply chain have generated conflicting claims about the full greenhouse gas footprint of natural gas. Top-down estimates based on large-scale atmospheric sampling often exceed bottom-up estimates based on source-based emission inventories. In this work, we reconcile top-down and bottom-up methane emissions estimates in one of the country’s major natural gas production basins using easily replicable measureme...

  13. Relative Entropies and Jensen Divergences in the Classical Limit

    Directory of Open Access Journals (Sweden)

    A. M. Kowalski

    2015-01-01

    Full Text Available Metrics and distances in probability spaces have shown to be useful tools for physical purposes. Here we use this idea, with emphasis on Jensen Divergences and relative entropies, to investigate features of the road towards the classical limit. A well-known semiclassical model is used and recourse is made to numerical techniques, via the well-known Bandt and Pompe methodology, to extract probability distributions from the pertinent time-series associated with dynamical data.

  14. Chromosomal speciation and molecular divergence - Accelerated evolution in rearranged chromosomes

    OpenAIRE

    Navarro, Arcadi; Barton, Nick

    2003-01-01

    Humans and their closest evolutionary relatives, the chimpanzees, differ in ~1.24% of their genomic DNA sequences. The fraction of these changes accumulated during the speciation processes that have separated the two lineages may be of special relevance in understanding the basis of their differences. We analyzed human and chimpanzee sequence data to search for the patterns of divergence and polymorphism predicted by a theoretical model of speciation. According to the model, positively select...

  15. Kullback-Leibler Divergence Approach to Partitioned Update Kalman Filter

    OpenAIRE

    Raitoharju, Matti; García-Fernández, Ángel F.; Piché, Robert

    2016-01-01

    Kalman filtering is a widely used framework for Bayesian estimation. The partitioned update Kalman filter applies a Kalman filter update in parts so that the most linear parts of measurements are applied first. In this paper, we generalize partitioned update Kalman filter, which requires the use oft the second order extended Kalman filter, so that it can be used with any Kalman filter extension. To do so, we use a Kullback-Leibler divergence approach to measure the nonlinearity of the measure...

  16. Singular divergence instability thresholds of kinematically constrained circulatory systems

    International Nuclear Information System (INIS)

    Static instability or divergence threshold of both potential and circulatory systems with kinematic constraints depends singularly on the constraints' coefficients. Particularly, the critical buckling load of the kinematically constrained Ziegler's pendulum as a function of two coefficients of the constraint is given by the Plücker conoid of degree n=2. This simple mechanical model exhibits a structural instability similar to that responsible for the Velikhov–Chandrasekhar paradox in the theory of magnetorotational instability.

  17. Evidence for five divergent thioredoxin h sequences in Arabidopsis thaliana.

    OpenAIRE

    Rivera-Madrid, R.; Mestres, D; Marinho, P.; Jacquot, J P; Decottignies, P; Miginiac-Maslow, M; Meyer, Y.

    1995-01-01

    Five different clones encoding thioredoxin homologues were isolated from Arabidopsis thaliana cDNA libraries. On the basis of the sequences they encode divergent proteins, but all belong to the cytoplasmic thioredoxins h previously described in higher plants. The five proteins obtained by overexpressing the coding sequences in Escherichia coli present typical thioredoxin activities (NADP(+)-malate dehydrogenase activation and reduction by Arabidopsis thioredoxin reductase) despite the presenc...

  18. Does alexithymia explain variation in cue-elicited craving reported by methamphetamine-dependent individuals?

    Science.gov (United States)

    Saladin, Michael E; Santa Ana, Elizabeth J; LaRowe, Steven D; Simpson, Annie N; Tolliver, Bryan K; Price, Kimber L; McRae-Clark, Aimee L; Brady, Kathleen T

    2012-01-01

    Drug craving is an important motivational phenomenon among addicted individuals, and successful management of craving is essential to both the initiation and maintenance of abstinence. Although craving in response to drug cues is common in drug-dependent individuals, it is not universal. At the present time, it is not known why approximately 20-30% of all addicted persons fail to report appreciable craving in laboratory-based cue reactivity studies. This study examined the possibility that alexithymia, a personality attribute characterized by a difficulty identifying and describing emotions, may contribute to the impoverished cue-elicited craving experienced by some addicts. Specifically, we tested the hypothesis that alexithymia, as measured by the Toronto Alexithymia Scale (TAS), would be inversely related to the magnitude of cue-elicited craving obtained in a cue reactivity protocol. Forty methamphetamine-dependent individuals completed the TAS and provided craving ratings for methamphetamine after presentation of methamphetamine-associated cues. Thirteen participants (32%) reported no methamphetamine cue-elicited craving. Contrary to expectation, TAS factor 1 (a measure of difficulty identifying feelings) scores were positively associated with cue-elicited craving. Thus, the results suggest that increasing difficulty-identifying feelings may be associated with higher cue-elicited craving. Clinical implications for this finding are discussed.

  19. The capsaicin cough reflex in eczema patients with respiratory symptoms elicited by perfume.

    Science.gov (United States)

    Elberling, Jesper; Dirksen, Asger; Johansen, Jeanne Duus; Mosbech, Holger

    2006-03-01

    Respiratory symptoms elicited by perfume are common in the population but have unclear pathophysiology. Increased capsaicin cough responsiveness has been associated with the symptoms, but it is unknown whether the site of the symptoms in the airways influences this association. The aim of this study was to investigate the association between the site of airway symptoms elicited by perfume and cough responsiveness to bronchial challenge with capsaicin. 21 eczema patients with respiratory symptoms elicited by perfume were compared with 21 healthy volunteers in a sex- and age-matched case control study. The participants completed a symptom questionnaire and underwent a bronchial challenge with capsaicin. Lower, but not upper, respiratory symptoms elicited by perfume were associated with increased capsaicin cough responsiveness. Having severe symptoms to perfume (n=11) did not relate to the site of the symptoms in the airways and was not associated with increased capsaicin cough responsiveness. In conclusion, respiratory symptoms elicited by perfume may reflect local hyperreactivity related to defensive reflexes in the airways, and measurements of the capsaicin cough reflex are relevant when patients with lower respiratory symptoms related to environmental perfume exposures are investigated.

  20. The capsaicin cough reflex in eczema patients with respiratory symptoms elicited by perfume

    DEFF Research Database (Denmark)

    Elberling, Jesper; Dirksen, Asger; Johansen, Jeanne Duus;

    2006-01-01

    Respiratory symptoms elicited by perfume are common in the population but have unclear pathophysiology. Increased capsaicin cough responsiveness has been associated with the symptoms, but it is unknown whether the site of the symptoms in the airways influences this association. The aim of this st......Respiratory symptoms elicited by perfume are common in the population but have unclear pathophysiology. Increased capsaicin cough responsiveness has been associated with the symptoms, but it is unknown whether the site of the symptoms in the airways influences this association. The aim...... of this study was to investigate the association between the site of airway symptoms elicited by perfume and cough responsiveness to bronchial challenge with capsaicin. 21 eczema patients with respiratory symptoms elicited by perfume were compared with 21 healthy volunteers in a sex- and age-matched case...... control study. The participants completed a symptom questionnaire and underwent a bronchial challenge with capsaicin. Lower, but not upper, respiratory symptoms elicited by perfume were associated with increased capsaicin cough responsiveness. Having severe symptoms to perfume (n=11) did not relate...

  1. Comparison of elicitation potential of chloroatranol and atranol--2 allergens in oak moss absolute.

    Science.gov (United States)

    Johansen, Jeanne D; Bernard, Guillaume; Giménez-Arnau, Elena; Lepoittevin, Jean-Pierre; Bruze, Magnus; Andersen, Klaus E

    2006-04-01

    Chloroatranol and atranol are degradation products of chloroatranorin and atranorin, respectively, and have recently been identified as important contact allergens in the natural fragrance extract, oak moss absolute. Oak moss absolute is widely used in perfumery and is the cause of many cases of fragrance allergic contact dermatitis. Chloroatranol elicits reactions at very low levels of exposure. In oak moss absolute, chloroatranol and atranol are present together and both may contribute to the allergenicity and eliciting capacity of the natural extract. In this study, 10 eczema patients with known sensitization to chloroatranol and oak moss absolute were tested simultaneously to a serial dilution of chloroatranol and atranol in ethanol, in equimolar concentrations (0.0034-1072 microM). Dose-response curves were estimated and analysed by logistic regression. The estimated difference in elicitation potency of chloroatranol relative to atranol based on testing with equimolar concentrations was 217% (95% confidence interval 116-409%). Both substances elicited reactions at very low levels of exposure. It is concluded that the differences in elicitation capacity between the 2 substances are counterbalanced by exposure being greater to atranol than to chloroatranol and that both substances contribute to the clinical problems seen in oak moss absolute-sensitized individuals. PMID:16650093

  2. Human antigen-presenting cells respond differently to gut-derived probiotic bacteria but mediate similar strain-dependent NK and T cell activation

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Zeuthen, Louise Hjerrild; Ferlazzo, Guido;

    2007-01-01

    (APC) was compared; blood myeloid dendritic cells (DC), monocyte-derived DC and monocytes, and the effector response of natural killer cells and naïve T cells was characterized. Maturation induced by gut-derived bacteria differed between APC, with blood DC and monocytes responding with the production...... of IL-6 and tumour necrosis factor-alpha to bacteria, which elicited mainly IL-10 in monocyte-derived DC. In contrast, comparable IFN-gamma production patterns were found in both natural killer cells and T cells induced by all bacteria-matured APC. An inhibitory effect of certain strains on this IFN......, in vitro assessment of the immunomodulatory effects of distinct strains may depend strongly on the cell type used as a model. To select the most appropriate model for screening of beneficial bacteria in human cells, the response to strains of intestinal bacteria of three types of antigen-presenting cells...

  3. Adaptive divergence in embryonic thermal plasticity among Atlantic salmon populations.

    Science.gov (United States)

    Côte, J; Roussel, J-M; Le Cam, S; Guillaume, F; Evanno, G

    2016-08-01

    In the context of global changes, the long-term viability of populations of endangered ectotherms may depend on their adaptive potential and ability to cope with temperature variations. We measured responses of Atlantic salmon embryos from four populations to temperature variations and used a QST -FST approach to study the adaptive divergence among these populations. Embryos were reared under two experimental conditions: a low temperature regime at 4 °C until eyed-stage and 10 °C until the end of embryonic development and a high temperature regime with a constant temperature of 10 °C throughout embryonic development. Significant variations among populations and population × temperature interactions were observed for embryo survival, incubation time and length. QST was higher than FST in all but one comparison suggesting an important effect of divergent selection. QST was also higher under the high-temperature treatment than at low temperature for length and survival due to a higher variance among populations under the stressful warmer treatment. Interestingly, heritability was lower for survival under high temperature in relation to a lower additive genetic variance under that treatment. Overall, these results reveal an adaptive divergence in thermal plasticity in embryonic life stages of Atlantic salmon suggesting that salmon populations may differentially respond to temperature variations induced by climate change. These results also suggest that changes in temperature may alter not only the adaptive potential of natural populations but also the selection regimes among them. PMID:27177256

  4. Velocity field measurements in oblique static divergent vocal fold models

    Science.gov (United States)

    Erath, Byron

    2005-11-01

    During normal phonation, the vocal fold cycle is characterized by the glottal opening transitioning from a convergent to a divergent passage and then closing before the cycle is repeated. Under ordinary phonatory conditions, both vocal folds, which form the glottal passage, move in phase with each other, creating a time-varying symmetric opening. However, abnormal pathological conditions, such as unilateral paralysis, and polyps, can result in geometrical asymmetries between the vocal folds throughout the phonatory cycle. This study investigates pulsatile flow fields through 7.5 times life-size vocal fold models with included divergence angles of 5 to 30 degrees, and obliquities between the vocal folds of up to 15 degrees. Flow conditions were scaled to match physiological parameters. Data were taken at the anterior posterior mid-plane using phase-averaged Particle Image Velocimetry (PIV). Viscous flow phenomena including the Coanda effect, flow separation points, and jet "flapping" were investigated. The results are compared to previously reported work of flow through symmetric divergent vocal fold models.

  5. Bayesian-Pearson Divergence Estimator Based on Grouped Data

    Institute of Scientific and Technical Information of China (English)

    BaoxueZhang; QingxunMeng

    2004-01-01

    A new method along with Bayesian approach for estimating the parameter in the distribution function F(x; θ) by using grouped data is developed in this paper. The support of F(x;θ) is divided into disjointed intervals as -∞ = x0 < x1 <… < xk-1 divergence D(p; q) is introduced to scale the distance between the probabilities pj(θ),j = 1,..., k and the samples from the posterior distribution (Dirichlet distribution) of the probabilities. Then by minimizing the Pearson divergence D(p;q), the ‘posterior' samples of the parameter θ can be obtained, through which statistical inference including Bayesian-Pearson Divergence Estimator of the parameter can be processed. Simulations and a numerical example emt:loying this method are presented.

  6. Beam divergence effects on high power optical parametric oscillation

    Institute of Scientific and Technical Information of China (English)

    Li Hui-Qing; Geng Ai-Cong; Bo Yong; Wu Ling-An; Cui Da-Fu; Xu Zu-Yan

    2005-01-01

    The beam divergence effects of the input pump laser on a high power nanosecond optical parametric oscillator (OPO) have been numerically simulated. The OPO conversion efficiency is affected due to the angular deviation of real laser beams from ideal phase matching conditions. Our theoretical model is based on the decomposition of the Gaussian beam and assumes each component has a single deviation angle and thus a Particular wave vector mismatch. We take into account the variable intensity profile in the spatial and temporal domains of the Gaussian beam, the pump depletion effects for large-signal processes as well as the oscillatory effects of the three waves. Two nonlinear crystals β-BaB2O4 (BBO) and LiB3O5 (LBO) have been investigated in detail. The results indicate that the degree of beam divergence strongly influences the maximum pump intensity, optimum crystal length and OPO conversion efficiency.The impact of beam divergence is much more severe in the case of critical phase-matching for BBO than in the case of non-critical phase-matching for LBO. The results provide a way to choose the optimum parameters for a high power ns OPO such as the nonlinear material, the crystal length and the pump intensity, etc. Good agreement is obtained with our experimental results.

  7. Peaches tree genetic divergence for brown rot reaction

    Directory of Open Access Journals (Sweden)

    Américo Wagner Júnior

    2011-10-01

    Full Text Available It was evaluated the genetic divergence in peach genotypes for brown rot reaction. It was evaluated 26 and 29 peach genotypes in the 2009/2010 and 2010/2011 production cycle, respectively. The experiment was carried out at the Laboratório de Fitossanidade, da UTFPR - Campus Dois Vizinhos. The experimental design was entirely randomized, considering each peach genotype a treatment, and it was use three replication of nine fruits. The treatment control use three replication of three peach. The fruit epidermis were inoculated individually with 0.15 mL of M. fructicola conidial suspension (1.0 x 10(5 spores mL-1. In the control treatment was sprayed with 0.15 mL of distilled water. The fruits were examined 72 and 120 hours after inoculation, and the incidence and severity disease were evaluated. These results allowed realized study for genetic divergence, used as dissimilarity measure the Generalized Mahalanobis distance. Cluster analysis using Tocher´s optimization method and distances in the plan were applied. There was smallest genetic divergence among peach trees evaluated for brown rot, what can difficult to obtain resistance in the genotypes.

  8. Automatic leukocyte nucleus segmentation by intuitionistic fuzzy divergence based thresholding.

    Science.gov (United States)

    Jati, Arindam; Singh, Garima; Mukherjee, Rashmi; Ghosh, Madhumala; Konar, Amit; Chakraborty, Chandan; Nagar, Atulya K

    2014-03-01

    The paper proposes a robust approach to automatic segmentation of leukocyte's nucleus from microscopic blood smear images under normal as well as noisy environment by employing a new exponential intuitionistic fuzzy divergence based thresholding technique. The algorithm minimizes the divergence between the actual image and the ideally thresholded image to search for the final threshold. A new divergence formula based on exponential intuitionistic fuzzy entropy has been proposed. Further, to increase its noise handling capacity, a neighborhood-based membership function for the image pixels has been designed. The proposed scheme has been applied on 110 normal and 54 leukemia (chronic myelogenous leukemia) affected blood samples. The nucleus segmentation results have been validated by three expert hematologists. The algorithm achieves an average segmentation accuracy of 98.52% in noise-free environment. It beats the competitor algorithms in terms of several other metrics. The proposed scheme with neighborhood based membership function outperforms the competitor algorithms in terms of segmentation accuracy under noisy environment. It achieves 93.90% and 94.93% accuracies for Speckle and Gaussian noises, respectively. The average area under the ROC curves comes out to be 0.9514 in noisy conditions, which proves the robustness of the proposed algorithm.

  9. Dynamics of detonations with a constant mean flow divergence

    CERN Document Server

    Borzou, Bijan

    2016-01-01

    The present work addresses the question of whether mean field macroscopic models are suitable to describe the dynamics of real cellular detonations. This question is posed in the framework of detonations with stream-tube area divergence that is kept constant, as to generate attenuated detonations in quasi-steady state. An exponential horn geometry is used, in order to keep the source term due to geometrical divergence constant in the governing equations of mean flow, and hence permit to establish steady travelling waves with constant losses. The experiments were conducted in two mixtures 2C$_2$H$_2$+5O$_2$+21Ar, characterized by a relatively weak instability, and C$_3$H$_8$+5O$_2$, characterized by a much more unstable cellular structure. The experiments demonstrated that such quasi-steady state detonations can be realized. The experiments permitted a unique detonation speed - divergence scaling laws to be developed. Quantitative comparisons were made with steady wave predictions based on the underlying chemi...

  10. Three dimensional simulations of viscous folding in diverging microchannels

    CERN Document Server

    Xu, Bingrui; Shin, Seungwon; Juric, Damir

    2016-01-01

    Three dimensional simulations on the viscous folding in diverging microchannels reported by Cubaud and Mason are performed using the parallel code BLUE for multi-phase flows. The more viscous liquid L_1 is injected into the channel from the center inlet, and the less viscous liquid L_2 from two side inlets. Liquid L_1 takes the form of a thin filament due to hydrodynamic focusing in the long channel that leads to the diverging region. The thread then becomes unstable to a folding instability, due to the longitudinal compressive stress applied to it by the diverging flow of liquid L_2. Given the long computation time, we were limited to a parameter study comprising five simulations in which the flow rate ratio, the viscosity ratio, the Reynolds number, and the shape of the channel were varied relative to a reference model. In our simulations, the cross section of the thread produced by focusing is elliptical rather than circular. The initial folding axis can be either parallel or perpendicular to the narrow di...

  11. [Genetic resources of nodule bacteria].

    Science.gov (United States)

    Rumiantseva, M L

    2009-09-01

    Nodule bacteria (rhizobia) form highly specific symbiosis with leguminous plants. The efficiency of accumulation of biological nitrogen depends on molecular-genetic interaction between the host plant and rhizobia. Genetic characteristics of microsymbiotic strains are crucial in developing highly productive and stress-resistant symbiotic pairs: rhizobium strain-host plant cultivar (species). The present review considers the issue of studying genetic resources of nodule bacteria to identify genes and their blocks, responsible for the ability of rhizobia to form highly effective symbiosis in various agroecological conditions. The main approaches to investigation of intraspecific and interspecific genetic and genomic diversity of nodule bacteria are considered, from MLEE analysis to the recent methods of genomic DNA analysis using biochips. The data are presented showing that gene centers of host plants are centers of genetic diversification of nodule bacteria, because the intraspecific polymorphism of genetic markers of the core and the accessory rhizobial genomes is extremely high in them. Genotypic features of trapped and nodule subpopulations of alfalfa nodule bacteria are discussed. A survey of literature showed that the genomes of natural strains in alfalfa gene centers exhibit significant differences in genes involved in control of metabolism, replication, recombination, and the formation of defense response (hsd genes). Natural populations of rhizobia are regarded as a huge gene pool serving as a source of evolutionary innovations.

  12. Divergent mucosal and systemic responses in children in response to acute otitis media.

    Science.gov (United States)

    Verhoeven, D; Pichichero, M E

    2014-10-01

    Acute otitis media (AOM), induced by respiratory bacteria, is a significant cause of children seeking medical attention worldwide. Some children are highly prone to AOMs, suffering three to four recurrent infections per year (prone). We previously determined that this population of children could have diminished anti-bacterial immune responses in peripheral blood that could fail to limit bacterial colonization in the nasopharynx (NP). Here, we examined local NP and middle ear (ME) responses and compared them to peripheral blood to examine whether the mucosa responses were similar to the peripheral blood responses. Moreover, we examined differences in effector cytokine responses between these two populations in the NP, ME and blood compartments at the onset of an AOM caused by either Streptococcus pneumoniae or non-typeable Haemophilus influenzae. We found that plasma effector cytokines patterned antigen-recall responses of CD4 T cells, with lower responses detected in prone children. ME cytokine levels did not mirror blood, but were more similar to the NP. Interferon (IFN)-γ and interleukin (IL)-17 in the NP were similar in prone and non-prone children, while IL-2 production was higher in prone children. The immune responses diverged in the mucosal and blood compartments at the onset of a bacterial ME infection, thus highlighting differences between local and systemic immune responses that could co-ordinate anti-bacterial immune responses in young children.

  13. Hemispheric Connectivity and the Visual-Spatial Divergent-Thinking Component of Creativity

    Science.gov (United States)

    Moore, Dana W.; Bhadelia, Rafeeque A.; Billings, Rebecca L.; Fulwiler, Carl; Heilman, Kenneth M.; Rood, Kenneth M. J.; Gansler, David A.

    2009-01-01

    Background/hypothesis: Divergent thinking is an important measurable component of creativity. This study tested the postulate that divergent thinking depends on large distributed inter- and intra-hemispheric networks. Although preliminary evidence supports increased brain connectivity during divergent thinking, the neural correlates of this…

  14. IDENTIFICATION OF BACTERIA IN LATEX PAINTS

    Directory of Open Access Journals (Sweden)

    Rojas, J.

    2008-01-01

    Full Text Available The bacteria are prokaryote organisms with a high capacity to colonize many types of habits. This research was developed with the object to identify extremophiles bacteria presents in latex paint. The bacteria were cultivated in culture mediums TSA, Blood Agar, Mc Conkey and finally the biochemical proof API-NF® for bacteria's isolation and identification, respectively. Characterization showed bacterial profile of Pasteurella sp. Hypothesis that could be found extremophiles bacteria in latex paint were demonstrated.

  15. Eliciting EuroQol descriptive data and utility scale values from inpatients. A feasibility study.

    Science.gov (United States)

    Selai, C; Rosser, R

    1995-08-01

    We conducted a microstudy to elicit health state descriptions and utility values, using the EuroQol instrument, from a sample of acutely ill inpatients on 5 wards at University College London Medical School. Most current work to date has elicited such descriptive and valuation data from random surveys of the general population. One problem with this is that most responders from the general population have not actually experienced the states being valued. Our goal was to ascertain whether there were any differences between the values given by inpatients and those of the general population. However, the small sample size of patients included in our feasibility study means our conclusions must remain tentative. Nevertheless, the results suggest that patients give higher values than the general population. We suggest that more research needs to be done eliciting values from patients. PMID:10155609

  16. Methylotrophic bacteria in sustainable agriculture.

    Science.gov (United States)

    Kumar, Manish; Tomar, Rajesh Singh; Lade, Harshad; Paul, Diby

    2016-07-01

    Excessive use of chemical fertilizers to increase production from available land has resulted in deterioration of soil quality. To prevent further soil deterioration, the use of methylotrophic bacteria that have the ability to colonize different habitats, including soil, sediment, water, and both epiphytes and endophytes as host plants, has been suggested for sustainable agriculture. Methylotrophic bacteria are known to play a significant role in the biogeochemical cycle in soil ecosystems, ultimately fortifying plants and sustaining agriculture. Methylotrophs also improve air quality by using volatile organic compounds such as dichloromethane, formaldehyde, methanol, and formic acid. Additionally, methylotrophs are involved in phosphorous, nitrogen, and carbon cycling and can help reduce global warming. In this review, different aspects of the interaction between methylotrophs and host plants are discussed, including the role of methylotrophs in phosphorus acquisition, nitrogen fixation, phytohormone production, iron chelation, and plant growth promotion, and co-inoculation of these bacteria as biofertilizers for viable agriculture practices. PMID:27263015

  17. Methylotrophic bacteria in sustainable agriculture.

    Science.gov (United States)

    Kumar, Manish; Tomar, Rajesh Singh; Lade, Harshad; Paul, Diby

    2016-07-01

    Excessive use of chemical fertilizers to increase production from available land has resulted in deterioration of soil quality. To prevent further soil deterioration, the use of methylotrophic bacteria that have the ability to colonize different habitats, including soil, sediment, water, and both epiphytes and endophytes as host plants, has been suggested for sustainable agriculture. Methylotrophic bacteria are known to play a significant role in the biogeochemical cycle in soil ecosystems, ultimately fortifying plants and sustaining agriculture. Methylotrophs also improve air quality by using volatile organic compounds such as dichloromethane, formaldehyde, methanol, and formic acid. Additionally, methylotrophs are involved in phosphorous, nitrogen, and carbon cycling and can help reduce global warming. In this review, different aspects of the interaction between methylotrophs and host plants are discussed, including the role of methylotrophs in phosphorus acquisition, nitrogen fixation, phytohormone production, iron chelation, and plant growth promotion, and co-inoculation of these bacteria as biofertilizers for viable agriculture practices.

  18. Chitin Degradation In Marine Bacteria

    DEFF Research Database (Denmark)

    Paulsen, Sara; Machado, Henrique; Gram, Lone

    2015-01-01

    Introduction: Chitin is the most abundant polymer in the marine environment and the second most abundant in nature. Chitin does not accumulate on the ocean floor, because of microbial breakdown. Chitin degrading bacteria could have potential in the utilization of chitin as a renewable carbon...... and nitrogen source in the fermentation industry.Methods: Here, whole genome sequenced marine bacteria were screened for chitin degradation using phenotypic and in silico analyses.Results: The in silico analyses revealed the presence of three to nine chitinases in each strain, however the number of chitinases...... chitin regulatory system.Conclusions: This study has provided insight into the ecology of chitin degradation in marine bacteria. It also served as a basis for choosing a more efficient chitin degrading production strain e.g. for the use of chitin waste for large-scale fermentations....

  19. Adaptation, Bacteria and Maxwell's Demons

    Science.gov (United States)

    Galajda, Peter; Keymer, Juan E.; Austin, Robert H.

    2007-03-01

    We propose a method to study the adaptation of bacterial populations with an asymmetric wall of Maxwell Demon openings. A Maxwell Demon opening is a funnel which is easier to enter than to leave. The interaction of swimming cells with such a Maxwell Demon Wall results in a population density separation, in apparent (but not real) violation of the Second Law of Thermodynamics, as we will show. Bacteria can be exposed to spatial challenges in order to move to e. g. higher food levels. The question we address in these experiments is: do the bacteria adapt and overcome the Maxwell Demon Wall?

  20. Explaining choice option attractiveness by beliefs elicited by the laddering method

    DEFF Research Database (Denmark)

    Grunert, Klaus G.; Bech-Larsen, Tino

    2005-01-01

    It is a common approach to explain choice option attractiveness by beliefs about the choice option. The means'end chain model is used to distinguish between various types of beliefs, depending on whether the belief links the choice option to attributes, consequences, or values related to the choice...... elicited by the laddering method increase explanatory power with regard to choice option attractiveness beyond the beliefs elicited by the Ajzen and Fishbein method, and that this additional explanatory power was due to those beliefs which relate the choice option to concepts with a higher level...

  1. Expert Elicitation Methods in Quantifying the Consequences of Acoustic Disturbance from Offshore Renewable Energy Developments.

    Science.gov (United States)

    Donovan, Carl; Harwood, John; King, Stephanie; Booth, Cormac; Caneco, Bruno; Walker, Cameron

    2016-01-01

    There are many developments for offshore renewable energy around the United Kingdom whose installation typically produces large amounts of far-reaching noise, potentially disturbing many marine mammals. The potential to affect the favorable conservation status of many species means extensive environmental impact assessment requirements for the licensing of such installation activities. Quantification of such complex risk problems is difficult and much of the key information is not readily available. Expert elicitation methods can be employed in such pressing cases. We describe the methodology used in an expert elicitation study conducted in the United Kingdom for combining expert opinions based on statistical distributions and copula-like methods.

  2. LAGRANGE MULTIPLIERS IN THE PROBABILITY DISTRIBUTIONS ELICITATION PROBLEM: AN APPLICATION TO THE 2013 FIFA CONFEDERATIONS CUP

    Directory of Open Access Journals (Sweden)

    Diogo de Carvalho Bezerra

    2015-12-01

    Full Text Available ABSTRACT Contributions from the sensitivity analysis of the parameters of the linear programming model for the elicitation of experts' beliefs are presented. The process allows for the calibration of the family of probability distributions obtained in the elicitation process. An experiment to obtain the probability distribution of a future event (Brazil vs. Spain soccer game in the 2013 FIFA Confederations Cup final game was conducted. The proposed sensitivity analysis step may help to reduce the vagueness of the information given by the expert.

  3. Lactic Acid Bacteria Inducing a Weak Interleukin-12 and Tumor Necrosis Alpha Response in Human Dendritic Cells Inhibit Strongly Stimulating Lactic Acid Bacteria but Act Synergistically with Gram-Negative Bacteria

    DEFF Research Database (Denmark)

    Zeuthen, Louise Hjerrild; Christensen, Hanne Risager; Frøkiær, Hanne

    2006-01-01

    The development and maintenance of immune homeostasis indispensably depend on signals from the gut flora. Lactic acid bacteria (LAB), which are gram-positive (G+) organisms, are plausible significant players and have received much attention. Gram-negative (G-) commensals, such as members of the f......The development and maintenance of immune homeostasis indispensably depend on signals from the gut flora. Lactic acid bacteria (LAB), which are gram-positive (G+) organisms, are plausible significant players and have received much attention. Gram-negative (G-) commensals, such as members...... of the family Enterobacteriaceae, may, however, be immunomodulators that are as important as G+ organisms but tend to be overlooked. Dendritic cells (DCs) are crucial immune regulators, and therefore, the present study aimed at investigating differences among human gut flora-derived LAB and G- bacteria....... These much divergent DC stimulation patterns among intestinal bacteria, which encompass both antagonistic and synergistic relationships, support the growing evidence that the composition of the gut flora affects immune regulation and that compositional imbalances may be involved in disease etiology....

  4. Convergence in feeling, divergence in physiology: How culture influences the consequences of disgust suppression and amplification among European Americans and Asian Americans.

    Science.gov (United States)

    Soto, José A; Lee, Elizabeth A; Roberts, Nicole A

    2016-01-01

    Much empirical work documents the downsides of suppressing emotions. Emerging research points to the need for a more sophisticated and culturally informed approach to understanding the consequences of emotion regulation. To that end, we employed behavioral, self-report, and psychophysiological measures to examine the consequences of two types of emotion regulation (suppression and amplification) in a sample of 28 Asian Americans and 31 European Americans. Participants were shown a neutral film and then a series of disgust-eliciting films during which they were asked to regulate their response by suppressing or amplifying their emotional behavior (counterbalanced). Despite self-reporting equal levels of disgust, European Americans showed greater skin conductance reactivity than Asian Americans in both regulation conditions, but not in response to a neutral film. These findings extend work on divergence in the consequences of emotion regulation across different cultural groups, which could help identify optimal emotion regulation strategies for health and well-being. PMID:26681616

  5. Research Synthesis Methods in an Age of Globalized Risks: Lessons from the Global Burden of Foodborne Disease Expert Elicitation

    DEFF Research Database (Denmark)

    Hald, Tine; Angulo, Fred; Bin Hamzah, Wan Mansor;

    2016-01-01

    We live in an age that increasingly calls for national or regional management of global risks. This article discusses the contributions that expert elicitation can bring to efforts to manage global risks and identifies challenges faced in conducting expert elicitation at this scale. In doing so it...... draws on lessons learned from conducting an expert elicitation as part of the World Health Organizations (WHO) initiative to estimate the global burden of foodborne disease; a study commissioned by the Foodborne Disease Epidemiology Reference Group (FERG). Expert elicitation is designed to fill gaps in...... data and research using structured, transparent methods. Such gaps are a significant challenge for global risk modeling. Experience with the WHO FERG expert elicitation shows that it is feasible to conduct an expert elicitation at a global scale, but that challenges do arise, including: defining an...

  6. Sequence of inequalities among fuzzy mean difference divergence measures and their applications.

    Science.gov (United States)

    Tomar, Vijay Prakash; Ohlan, Anshu

    2014-01-01

    This paper presents a sequence of fuzzy mean difference divergence measures. The validity of these fuzzy mean difference divergence measures is proved axiomatically. In addition, it introduces a sequence of inequalities among some of these fuzzy mean difference divergence measures. The applications of proposed fuzzy mean difference divergence measures in the context of pattern recognition have been presented using a numerical example. It is shown that the proposed fuzzy mean difference divergence measures are well suited to use with linguistic variables. Finally, on establishing inequalities, we find that our proposed measures are computationally much more efficient.

  7. Velocity condensation for magnetotactic bacteria

    CERN Document Server

    Rupprecht, Jean-Francois; Bocquet, Lydéric

    2015-01-01

    Magnetotactic swimmers tend to align along magnetic field lines against stochastic reorientations. We show that the swimming strategy, e.g. active Brownian motion versus run-and-tumble dynamics, strongly affects the orientation statistics. The latter can exhibit a velocity condensation whereby the alignment probability density diverges. As a consequence, we find that the swimming strategy affects the nature of the phase transition to collective motion, indicating that L\\'evy run-and-tumble walks can outperform active Brownian processes as strategies to trigger collective behavior.

  8. Velocity Condensation for Magnetotactic Bacteria.

    Science.gov (United States)

    Rupprecht, Jean-François; Waisbord, Nicolas; Ybert, Christophe; Cottin-Bizonne, Cécile; Bocquet, Lydéric

    2016-04-22

    Magnetotactic swimmers tend to align along magnetic field lines against stochastic reorientations. We show that the swimming strategy, e.g., active Brownian motion versus run-and-tumble dynamics, strongly affects the orientation statistics. The latter can exhibit a velocity condensation whereby the alignment probability density diverges. As a consequence, we find that the swimming strategy affects the nature of the phase transition to collective motion, indicating that Lévy run-and-tumble walks can outperform active Brownian processes as strategies to trigger collective behavior. PMID:27152825

  9. Divergência genética em feijão-caupi Genetic divergence among cowpea

    Directory of Open Access Journals (Sweden)

    Adriana Rodrigues Passos

    2007-01-01

    Full Text Available Este trabalho objetivou avaliar a divergência genética entre genótipos de feijão-caupi, visando à seleção dos mais divergentes e de maior potencial produtivo para indicar como genitores em cruzamentos genéticos para futura recomendação de cultivares aos agricultores do Recôncavo Baiano. Os experimentos foram desenvolvidos na Escola de Agronomia da Universidade Federal da Bahia, Cruz das Almas (BA, utilizando-se 22 genótipos do tipo prostrado e 20 do tipo semi-ereto, dispostos em delineamento de blocos casualizados, com quatro repetições. Foram analisados os caracteres altura da planta, comprimento de vagem, massa de vagens, massa de grãos por vagem, número de grãos por vagem, massa de cem grãos, índice de grãos, produtividade de vagem e de grãos. A divergência genética foi obtida através da distância generalizada de Mahalanobis. Novas combinações gênicas promissoras podem surgir nos cruzamentos entre os genótipos TE97-309G-1, TE97-367G-3, TE97-367G-11 e TE97-430G-12 do tipo prostrado e TE97-321G-4 e TE97-404-1E-1 do tipo semi-ereto. A seleção dos genótipos TE93-244-23F-1, TE97-299G-10 e BR 17-Gurguéia tipo prostrado e os genótipos TE97-321G-4, TE97-406-2E, TE96-282-22G e EV x 91-2E-1 tipo semi-ereto demonstram superioridade para a produtividade de grãos. Os caracteres comprimento de vagem, massa de grãos por vagem e produtividade de vagens são os que mais contribuem para a divergência genética.This work aimed to evaluate the genetic divergence among cowpea genotypes, for selection of most divergent genotypes and of highest yield potential as parents in crossings as well as for future recommendation of cultivars in the reconcave region in Bahia, Brazil. The experiment was carried out Agronomy School of Universidade Federal da Bahia, Cruz das Almas, State of Bahia, using twenty two erect cowpea and twenty semi-erect cowpea genotypes, in a randomized design, with four replications. The following characters

  10. Updating in working memory predicts greater emotion reactivity to and facilitated recovery from negative emotion-eliciting stimuli

    OpenAIRE

    Pe, Madeline L.; Koval, Peter; Houben, Marlies; Erbas, Yasemin; Champagne, Dominique; Kuppens, Peter

    2015-01-01

    That emotions change in response to emotion-eliciting events is a natural part of human life. However, it is equally important for emotions to return to baseline once the emotion-eliciting events have passed. This suggests that the ability to emotionally react to and recover from emotion-eliciting events is critical for healthy psychological functioning. But why do individuals differ in their emotion reactivity and recovery? The present work postulates that the ability to update emotional inf...

  11. An Intercomparison Between Divergence-Cleaning and Staggered Mesh Formulations for Numerical Magnetohydrodynamics

    CERN Document Server

    Balsara, D; Balsara, Dinshaw; Kim, Jongsoo

    2003-01-01

    In recent years, several different strategies have emerged for evolving the magnetic field in numerical MHD. Some of these methods can be classified as divergence-cleaning schemes, where one evolves the magnetic field components just like any other variable in a higher order Godunov scheme. The fact that the magnetic field is divergence-free is imposed post-facto via a divergence-cleaning step. Other schemes for evolving the magnetic field rely on a staggered mesh formulation which is inherently divergence-free. The claim has been made that the two approaches are equivalent. In this paper we cross-compare three divergence-cleaning schemes based on scalar and vector divergence-cleaning and a popular divergence-free scheme. All schemes are applied to the same stringent test problem. Several deficiencies in all the divergence-cleaning schemes become clearly apparent with the scalar divergence-cleaning schemes performing worse than the vector divergence-cleaning scheme. The vector divergence-cleaning scheme also ...

  12. Manipulating Genetic Material in Bacteria

    Science.gov (United States)

    1998-01-01

    Lisa Crawford, a graduate research assistant from the University of Toledo, works with Laurel Karr of Marshall Space Flight Center (MSFC) in the molecular biology laboratory. They are donducting genetic manipulation of bacteria and yeast for the production of large amount of desired protein. Photo credit: NASA/Marshall Space Flight Center (MSFC)

  13. Engineering robust lactic acid bacteria

    NARCIS (Netherlands)

    Bron, P.A.; Bokhorst-van de Veen, van H.; Wels, M.; Kleerebezem, M.

    2011-01-01

    For centuries, lactic acid bacteria (LAB) have been industrially exploited as starter cultures in the fermentation of foods and feeds for their spoilage-preventing and flavor-enhancing characteristics. More recently, the health-promoting effects of LAB on the consumer have been widely acknowledged,

  14. Fuzzy species among recombinogenic bacteria

    Directory of Open Access Journals (Sweden)

    Fraser Christophe

    2005-03-01

    Full Text Available Abstract Background It is a matter of ongoing debate whether a universal species concept is possible for bacteria. Indeed, it is not clear whether closely related isolates of bacteria typically form discrete genotypic clusters that can be assigned as species. The most challenging test of whether species can be clearly delineated is provided by analysis of large populations of closely-related, highly recombinogenic, bacteria that colonise the same body site. We have used concatenated sequences of seven house-keeping loci from 770 strains of 11 named Neisseria species, and phylogenetic trees, to investigate whether genotypic clusters can be resolved among these recombinogenic bacteria and, if so, the extent to which they correspond to named species. Results Alleles at individual loci were widely distributed among the named species but this distorting effect of recombination was largely buffered by using concatenated sequences, which resolved clusters corresponding to the three species most numerous in the sample, N. meningitidis, N. lactamica and N. gonorrhoeae. A few isolates arose from the branch that separated N. meningitidis from N. lactamica leading us to describe these species as 'fuzzy'. Conclusion A multilocus approach using large samples of closely related isolates delineates species even in the highly recombinogenic human Neisseria where individual loci are inadequate for the task. This approach should be applied by taxonomists to large samples of other groups of closely-related bacteria, and especially to those where species delineation has historically been difficult, to determine whether genotypic clusters can be delineated, and to guide the definition of species.

  15. Evolutionary divergence of the APETALA1 and CAULIFLOWER proteins

    Institute of Scientific and Technical Information of China (English)

    Bin WANG; Ning ZHANG; Chun-Ce GUO; Gui-Xia XU; Hong-Zhi KONG; Hong-Yan SHAN

    2012-01-01

    APETALA1 (AP1) and CAULIFLOWER (CAL) are apair of paralogous genes that were generated through the pre-Brassicaceae whole-genome duplication event.AP1 and CAL have both partially redundant and unique functions.Previous studies have shown that the K and C regions of their proteins are essential for the functional divergence.However,which differences in these regions are the major contributors and how the differences were accumulated remain unknown.In the present study,we compared the sequences of the two proteins and identified five gaps and 55 amino acid replacements between them.Investigation of genomic sequences further indicated that the differences in the proteins were caused by non-synonymous substitutions and changes in exon-intron structures.Reconstruction of three-dimensional structures revealed that the sequence divergence of AP1 and CAL has resulted in differences between the two in terms of the number,length,position and orientation of α-helices,especially in the K and C regions.Comparisons of sequences and three-dimensional structures of ancestral proteins with AP1 and CAL suggest that the ancestral AP1 protein experienced fewer changes,whereas the ancestral CAL protein accumulated more changes shortly after gene duplication,relative to their common ancestor.Thereafter,AP1-like proteins experienced few mutations,whereas CAL-like proteins were not conserved until the diversification of the Brassicaceae lineage Ⅰ.This indicates that AP1- and CAL-like proteins evolved asymmetrically after gene duplication.These findings provide new insights into the functional divergence of AP1 and CAL genes.

  16. Generalization of entropy based divergence measures for symbolic sequence analysis.

    Directory of Open Access Journals (Sweden)

    Miguel A Ré

    Full Text Available Entropy based measures have been frequently used in symbolic sequence analysis. A symmetrized and smoothed form of Kullback-Leibler divergence or relative entropy, the Jensen-Shannon divergence (JSD, is of particular interest because of its sharing properties with families of other divergence measures and its interpretability in different domains including statistical physics, information theory and mathematical statistics. The uniqueness and versatility of this measure arise because of a number of attributes including generalization to any number of probability distributions and association of weights to the distributions. Furthermore, its entropic formulation allows its generalization in different statistical frameworks, such as, non-extensive Tsallis statistics and higher order Markovian statistics. We revisit these generalizations and propose a new generalization of JSD in the integrated Tsallis and Markovian statistical framework. We show that this generalization can be interpreted in terms of mutual information. We also investigate the performance of different JSD generalizations in deconstructing chimeric DNA sequences assembled from bacterial genomes including that of E. coli, S. enterica typhi, Y. pestis and H. influenzae. Our results show that the JSD generalizations bring in more pronounced improvements when the sequences being compared are from phylogenetically proximal organisms, which are often difficult to distinguish because of their compositional similarity. While small but noticeable improvements were observed with the Tsallis statistical JSD generalization, relatively large improvements were observed with the Markovian generalization. In contrast, the proposed Tsallis-Markovian generalization yielded more pronounced improvements relative to the Tsallis and Markovian generalizations, specifically when the sequences being compared arose from phylogenetically proximal organisms.

  17. Generalization of entropy based divergence measures for symbolic sequence analysis.

    Science.gov (United States)

    Ré, Miguel A; Azad, Rajeev K

    2014-01-01

    Entropy based measures have been frequently used in symbolic sequence analysis. A symmetrized and smoothed form of Kullback-Leibler divergence or relative entropy, the Jensen-Shannon divergence (JSD), is of particular interest because of its sharing properties with families of other divergence measures and its interpretability in different domains including statistical physics, information theory and mathematical statistics. The uniqueness and versatility of this measure arise because of a number of attributes including generalization to any number of probability distributions and association of weights to the distributions. Furthermore, its entropic formulation allows its generalization in different statistical frameworks, such as, non-extensive Tsallis statistics and higher order Markovian statistics. We revisit these generalizations and propose a new generalization of JSD in the integrated Tsallis and Markovian statistical framework. We show that this generalization can be interpreted in terms of mutual information. We also investigate the performance of different JSD generalizations in deconstructing chimeric DNA sequences assembled from bacterial genomes including that of E. coli, S. enterica typhi, Y. pestis and H. influenzae. Our results show that the JSD generalizations bring in more pronounced improvements when the sequences being compared are from phylogenetically proximal organisms, which are often difficult to distinguish because of their compositional similarity. While small but noticeable improvements were observed with the Tsallis statistical JSD generalization, relatively large improvements were observed with the Markovian generalization. In contrast, the proposed Tsallis-Markovian generalization yielded more pronounced improvements relative to the Tsallis and Markovian generalizations, specifically when the sequences being compared arose from phylogenetically proximal organisms.

  18. Chloroplast genome evolution in early diverged leptosporangiate ferns.

    Science.gov (United States)

    Kim, Hyoung Tae; Chung, Myong Gi; Kim, Ki-Joong

    2014-05-01

    In this study, the chloroplast (cp) genome sequences from three early diverged leptosporangiate ferns were completed and analyzed in order to understand the evolution of the genome of the fern lineages. The complete cp genome sequence of Osmunda cinnamomea (Osmundales) was 142,812 base pairs (bp). The cp genome structure was similar to that of eusporangiate ferns. The gene/intron losses that frequently occurred in the cp genome of leptosporangiate ferns were not found in the cp genome of O. cinnamomea. In addition, putative RNA editing sites in the cp genome were rare in O. cinnamomea, even though the sites were frequently predicted to be present in leptosporangiate ferns. The complete cp genome sequence of Diplopterygium glaucum (Gleicheniales) was 151,007 bp and has a 9.7 kb inversion between the trnL-CAA and trnVGCA genes when compared to O. cinnamomea. Several repeated sequences were detected around the inversion break points. The complete cp genome sequence of Lygodium japonicum (Schizaeales) was 157,142 bp and a deletion of the rpoC1 intron was detected. This intron loss was shared by all of the studied species of the genus Lygodium. The GC contents and the effective numbers of codons (ENCs) in ferns varied significantly when compared to seed plants. The ENC values of the early diverged leptosporangiate ferns showed intermediate levels between eusporangiate and core leptosporangiate ferns. However, our phylogenetic tree based on all of the cp gene sequences clearly indicated that the cp genome similarity between O. cinnamomea (Osmundales) and eusporangiate ferns are symplesiomorphies, rather than synapomorphies. Therefore, our data is in agreement with the view that Osmundales is a distinct early diverged lineage in the leptosporangiate ferns.

  19. Rethinking conformity and imitation: divergence, convergence, and social understanding.

    Science.gov (United States)

    Hodges, Bert H

    2014-01-01

    Social and developmental psychologists have stressed the pervasiveness and strength of humans' tendencies to conform and to imitate, and social anthropologists have argued that these tendencies are crucial to the formation of cultures. Research from four domains is reviewed and elaborated to show that divergence is also pervasive and potent, and it is interwoven with convergence in a complex set of dynamics that is often unnoticed or minimized. First, classic research in social conformity is reinterpreted in terms of truth, trust, and social solidarity, revealing that dissent is its most salient feature. Second, recent studies of children's use of testimony to guide action reveal a surprisingly sophisticated balance of trust and prudence, and a concern for truth and charity. Third, new experiments indicate that people diverge from others even under conditions where conformity seems assured. Fourth, current studies of imitation provide strong evidence that children are both selective and faithful in who, what, and why they follow others. All of the evidence reviewed points toward children and adults as being engaged, embodied partners with others, motivated to learn and understand the world, others, and themselves in ways that go beyond goals and rules, prediction and control. Even young children act as if they are in a dialogical relationship with others and the world, rather than acting as if they are solo explorers or blind followers. Overall, the evidence supports the hypothesis that social understanding cannot be reduced to convergence or divergence, but includes ongoing activities that seek greater comprehensiveness and complexity in the ability to act and interact effectively, appropriately, and with integrity.

  20. Diversity and habitat preferences of cultivated and uncultivated aerobic methanotrophic bacteria evaluated based on pmoA as molecular marker

    Directory of Open Access Journals (Sweden)

    Claudia eKnief

    2015-12-01

    Full Text Available Methane-oxidizing bacteria are characterized by their capability to grow on methane as sole source of carbon and energy. Cultivation-dependent and –independent methods have revealed that this functional guild of bacteria comprises a substantial diversity of organisms. In particular the use of cultivation-independent methods targeting a subunit of the particulate methane monooxygenase (pmoA as functional marker for the detection of aerobic methanotrophs has resulted in thousands of sequences representing unknown methanotrophic bacteria. This limits data interpretation due to restricted information about these uncultured methanotrophs. A few groups of uncultivated methanotrophs are assumed to play important roles in methane oxidation in specific habitats, while the biology behind other sequence clusters remains still largely unknown. The discovery of evolutionary related monooxygenases in non-methanotrophic bacteria and of pmoA paralogs in methanotrophs requires that sequence clusters of uncultivated organisms have to be interpreted with care. This review article describes the present diversity of cultivated and uncultivated aerobic methanotrophic bacteria based on pmoA gene sequence diversity. It summarizes current knowledge about cultivated and major clusters of uncultivated methanotrophic bacteria and evaluates habitat specificity of these bacteria at different levels of taxonomic resolution. Habitat specificity exists for diverse lineages and at different taxonomic levels. Methanotrophic genera such as Methylocystis and Methylocaldum are identified as generalists, but they harbor habitat specific methanotrophs at species level. This finding implies that future studies should consider these diverging preferences at different taxonomic levels when analyzing methanotrophic communities.

  1. Diversity and Habitat Preferences of Cultivated and Uncultivated Aerobic Methanotrophic Bacteria Evaluated Based on pmoA as Molecular Marker

    Science.gov (United States)

    Knief, Claudia

    2015-01-01

    Methane-oxidizing bacteria are characterized by their capability to grow on methane as sole source of carbon and energy. Cultivation-dependent and -independent methods have revealed that this functional guild of bacteria comprises a substantial diversity of organisms. In particular the use of cultivation-independent methods targeting a subunit of the particulate methane monooxygenase (pmoA) as functional marker for the detection of aerobic methanotrophs has resulted in thousands of sequences representing “unknown methanotrophic bacteria.” This limits data interpretation due to restricted information about these uncultured methanotrophs. A few groups of uncultivated methanotrophs are assumed to play important roles in methane oxidation in specific habitats, while the biology behind other sequence clusters remains still largely unknown. The discovery of evolutionary related monooxygenases in non-methanotrophic bacteria and of pmoA paralogs in methanotrophs requires that sequence clusters of uncultivated organisms have to be interpreted with care. This review article describes the present diversity of cultivated and uncultivated aerobic methanotrophic bacteria based on pmoA gene sequence diversity. It summarizes current knowledge about cultivated and major clusters of uncultivated methanotrophic bacteria and evaluates habitat specificity of these bacteria at different levels of taxonomic resolution. Habitat specificity exists for diverse lineages and at different taxonomic levels. Methanotrophic genera such as Methylocystis and Methylocaldum are identified as generalists, but they harbor habitat specific methanotrophs at species level. This finding implies that future studies should consider these diverging preferences at different taxonomic levels when analyzing methanotrophic communities. PMID:26696968

  2. A Novel Lactic Acid Bacteria Growth-stimulating Peptide from Broad Bean (Vicia faba . Protein Hydrolysates

    Directory of Open Access Journals (Sweden)

    Ping Xiao

    2015-03-01

    Full Text Available In this study, broad bean protein hydrolysates (BPH produced by alcalase with strong-stimulating activity for lactic acid bacteria (LAB was first time reported. In order to obtain the key peptide that have growth-stimulating activity for lactic acid bacteria (LAB, gel filtration chromatography and Reverse Phase High Performance Liquid Chromatography (RP-HPLC were applied to isolate and purify the peptides from BPH. Finally, F4-2 elicited the highest activity for LAB, corresponding to amino acid sequence Ser-Ala-Gln (304.10Da was identified by Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF/TOF MS/MS. Thus, this study shows that broad bean peptide is a good source to promote the LAB growth and this function is reported for the first time.

  3. Divergent IR gluon propagator from Ward-Slavnov-Taylor identities?

    CERN Document Server

    Boucaud, P; Lokhov, A Y; Micheli, J; Pène, O; Rodríguez-Quintero, J; Roiesnel, C; Yaouanc, A L; Boucaud, Ph.

    2007-01-01

    We exploit the Ward-Slavnov-Taylor identity relating the 3-gluons to the ghost-gluon vertices to conclude either that the ghost dressing function is finite and non vanishing at zero momentum while the gluon propagator diverges (although it may do so weakly enough not to be in contradiction with current lattice data) or that the 3-gluons vertex is non-regular when one momentum goes to zero. We stress that those results should be kept in mind when one studies the Infrared properties of the ghost and gluon propagators, for example by means of Dyson-Schwinger equations.

  4. Divergence measures and a general framework for local variational approximation.

    Science.gov (United States)

    Watanabe, Kazuho; Okada, Masato; Ikeda, Kazushi

    2011-12-01

    The local variational method is a technique to approximate an intractable posterior distribution in Bayesian learning. This article formulates a general framework for local variational approximation and shows that its objective function is decomposable into the sum of the Kullback information and the expected Bregman divergence from the approximating posterior distribution to the Bayesian posterior distribution. Based on a geometrical argument in the space of approximating posteriors, we propose an efficient method to evaluate an upper bound of the marginal likelihood. Moreover, we demonstrate that the variational Bayesian approach for the latent variable models can be viewed as a special case of this general framework.

  5. Fisher-like atomic divergences: Mathematical grounds and physical applications

    Science.gov (United States)

    Martín, A. L.; Angulo, J. C.; Antolín, J.

    2013-11-01

    Two different local divergence measures, the Fisher (FD) and the Jensen-Fisher (JFD) ones, are compared in this work by applying them to atomic one-particle densities in position and momentum spaces. They are defined in terms of the absolute and the relative Fisher information functionals. The analysis here afforded includes not only neutral atoms, but also singly-charged cations. The results are interpreted and justified according to (i) shell-filling patterns, (ii) short- and long-range behaviors of the atomic densities, and (iii) the value of the atomic ionization potential. The strengths of the FD measure, as compared to the JFD one, are emphasized.

  6. Inequalities among Differences of Gini Means and Divergence Measures

    CERN Document Server

    Taneja, Inder Jeet

    2011-01-01

    In 1938, Gini studied a mean having two parameters. Later, many authors studied properties of this mean. In particular, it contains the famous means as harmonic, geometric, arithmetic, etc. Here we considered sequences of inequalities arising due to particular values of the parameters in Gini's mean. This sequence generates many nonnegative differences. Not all of them are convex. We have studied here convexity of some of these differences and again established new inequalities. Considering in terms of probability distributions these differences, we have made connections with some of well known divergence measures.

  7. The divergent autoencoder (DIVA) model of category learning.

    Science.gov (United States)

    Kutrz, Kenneth J

    2007-08-01

    A novel theoretical approach to human category learning is proposed in which categories are represented as coordinated statistical models of the properties of the members. Key elements of the account are learning to recode inputs as task-constrained principle components and evaluating category membership in terms of model fit-that is, the fidelity of the reconstruction after recoding and decoding the stimulus. The approach is implemented as a computational model called DIVA (for DIVergent Autoencoder), an artificial neural network that uses reconstructive learning to solve N-way classification tasks. DIVA shows good qualitative fits to benchmark human learning data and provides a compelling theoretical alternative to established models. PMID:17972718

  8. Global divergence of the human follicle mite Demodex folliculorum

    DEFF Research Database (Denmark)

    Palopoli, Michael F.; Fergus, Daniel J.; Minot, Samuel;

    2015-01-01

    Microscopic mites of the genus Demodex live within the hair follicles of mammals and are ubiquitous symbionts of humans, but little molecular work has been done to understand their genetic diversity or transmission. Here we sampled mite DNA from 70 human hosts of diverse geographic ancestries......, indicating that transmission requires close contact. Dating analyses indicated that D. folliculorum origins may predate modern humans. Overall, D. folliculorum evolution reflects ancient human population divergences, is consistent with an out-of-Africa dispersal hypothesis, and presents an excellent model...... system for further understanding the history of human movement....

  9. Genetic divergence in popcorn lines detected by microsatellite

    OpenAIRE

    Thatiana Silva Dandolini; Carlos Alberto Scapim; Antônio Teixeira do Amaral Júnior; Claudete Aparecida Mangolin; Maria de Fátima Pires da Silva Machado; Andressa de Souza Mott; Ana Daniela Lopes

    2008-01-01

    The purpose of this study was to use microsatellite markers to evaluate the genetic divergence in 10 popcornlines. The number of alleles per locus ranged from 2 to 5. The proportion of polymorphic loci was highest (50%) in lineCuragua, while Zélia II was the most monomorphic (100%). The arithmetic complement of similarity of Roger and Tanimotofor the 10 lines indicated lower genetic similarity between the lines Zélia II and Avati Pichinga I and higher similarity betweenZélia I and Zélia II. T...

  10. Convergence of Contrastive Divergence Algorithm in Exponential Family

    OpenAIRE

    Wu, Tung-yu; Jiang, Bai; Jin, Yifan; Wong, Wing H.

    2016-01-01

    This paper studies the convergence properties of contrastive divergence algorithm for parameter inference in exponential family, by relating it to Markov chain theory and stochastic stability literature. We prove that, under mild conditions and given a finite data sample $X_1,\\dots,X_n \\sim p_{\\theta^*}$ i.i.d. in an event with probability approaching to 1, the sequence $\\{\\theta_t\\}_{t \\ge 0}$ generated by CD algorithm is a positive Harris recurrent chain, and thus processes an unique invari...

  11. Landau-Squire jet in a radially diverging electrical current

    Energy Technology Data Exchange (ETDEWEB)

    Boyarevich, V.V.; Shilova, E.I.

    1977-07-01

    An examination is made of a precise solution to the classical Landau-Squire problem in a radially diverging electrical current. The formulated problem was shown to be described by two parameters one of which characterizes the electromagnetic effect, and the other - the hydrodynamic impulse. Determinations were made of the regions of permissible parameter values at which the solution remains limited. Flow pictures are presented in relation to the input ratio of electromagnetic forces and the hydrodynamic impulse. 10 references, 6 figures, 2 tables.

  12. Porous waveguide facilitated low divergence quantum cascade laser*

    Institute of Scientific and Technical Information of China (English)

    Yin Wen; Lu Quanyong; Liu Wannfeng; Zhang Jinchuan; Wang Lijun; Liu Junqi; Li Lu; Liu Fengqi; Wang Zhanguo

    2011-01-01

    A quantum cscade laser with a porous waveguide structure emitting at 4.5 μm is reported. A branchlike porous structure filled with metal material was fabricated on both sides of the laser ridge by an electrochemical etching process. In contrast to the common ridge waveguide laser, devices with a porous structure give rather better beam quality. Utilizing this porous structure as a high-order mode absorber, the device exhibited fundamental transverse mode emission with a nearly diffraction limited far-field beam divergence angle of 4.9°.

  13. 76 FR 72372 - Request for Comments on Eliciting More Complete Patent Assignment Information

    Science.gov (United States)

    2011-11-23

    ... United States Patent and Trademark Office 37 CFR Part 3 Request for Comments on Eliciting More Complete Patent Assignment Information AGENCY: United States Patent and Trademark Office, Commerce. ACTION: Request for comments. SUMMARY: The United States Patent and Trademark Office (USPTO) is...

  14. Business Process Elicitation, Modeling, and Reengineering: Teaching and Learning with Simulated Environments

    Science.gov (United States)

    Jeyaraj, Anand

    2010-01-01

    The design of enterprise information systems requires students to master technical skills for elicitation, modeling, and reengineering business processes as well as soft skills for information gathering and communication. These tacit skills and behaviors cannot be effectively taught students but rather experienced and learned by students. This…

  15. Sequential Immunization Elicits Broadly Neutralizing Anti-HIV-1 Antibodies in Ig Knockin Mice.

    Science.gov (United States)

    Escolano, Amelia; Steichen, Jon M; Dosenovic, Pia; Kulp, Daniel W; Golijanin, Jovana; Sok, Devin; Freund, Natalia T; Gitlin, Alexander D; Oliveira, Thiago; Araki, Tatsuya; Lowe, Sarina; Chen, Spencer T; Heinemann, Jennifer; Yao, Kai-Hui; Georgeson, Erik; Saye-Francisco, Karen L; Gazumyan, Anna; Adachi, Yumiko; Kubitz, Michael; Burton, Dennis R; Schief, William R; Nussenzweig, Michel C

    2016-09-01

    A vaccine that elicits broadly neutralizing antibodies (bNAbs) against HIV-1 is likely to be protective, but this has not been achieved. To explore immunization regimens that might elicit bNAbs, we produced and immunized mice expressing the predicted germline PGT121, a bNAb specific for the V3-loop and surrounding glycans on the HIV-1 spike. Priming with an epitope-modified immunogen designed to activate germline antibody-expressing B cells, followed by ELISA-guided boosting with a sequence of directional immunogens, native-like trimers with decreasing epitope modification, elicited heterologous tier-2-neutralizing responses. In contrast, repeated immunization with the priming immunogen did not. Antibody cloning confirmed elicitation of high levels of somatic mutation and tier-2-neutralizing antibodies resembling the authentic human bNAb. Our data establish that sequential immunization with specifically designed immunogens can induce high levels of somatic mutation and shepherd antibody maturation to produce bNAbs from their inferred germline precursors. PMID:27610569

  16. Effects of Elicitation Task Variables on Speech Production by Children with Cochlear Implants

    Science.gov (United States)

    McCleary, Elizabeth A.; Ide-Helvie, Dana L.; Lotto, Andrew J.; Carney, Arlene Earley; Higgins, Maureen B.

    2007-01-01

    Given the interest in comparing speech production development in children with normal hearing and hearing impairment, it is important to evaluate how variables within speech elicitation tasks can differentially affect the acoustics of speech production for these groups. In a first experiment, children (6-14 years old) with cochlear implants…

  17. Eliciting and Developing Teachers' Conceptions of Random Processes in a Probability and Statistics Course

    Science.gov (United States)

    Smith, Toni M.; Hjalmarson, Margret A.

    2013-01-01

    The purpose of this study is to examine prospective mathematics specialists' engagement in an instructional sequence designed to elicit and develop their understandings of random processes. The study was conducted with two different sections of a probability and statistics course for K-8 teachers. Thirty-two teachers participated. Video analyses…

  18. Children with Autism Respond Differently to Spontaneous, Elicited and Deferred Imitation

    Science.gov (United States)

    Heimann, M.; Nordqvist, E.; Strid, K.; Connant Almrot, J.; Tjus, T.

    2016-01-01

    Background: Imitation, a key vehicle for both cognitive and social development, is often regarded as more difficult for children with autism spectrum disorders (ASD) than for children with Down syndrome (DS) or typically developing (TD) children. The current study investigates similarities and differences in observed elicited, spontaneous and…

  19. Muscle reflexes during gait elicited by electrical stimulation of the posterior cruciate ligament in humans

    DEFF Research Database (Denmark)

    Fischer-Rasmussen, T; Krogsgaard, M R; Jensen, D B;

    2002-01-01

    muscle motoneuron pool as evidenced by electromyography. The response elicited from the stimulation of the PCL was not limited to a specific muscle group but depended on ongoing muscle contraction, which suggests that the mechanoreceptors in the PCL are involved in the control of all muscles acting...

  20. Motivating and achievement-eliciting pop-ups in online environments: A user experience perspective

    NARCIS (Netherlands)

    Bittner, Jenny V.; Zondervan, Robin

    2015-01-01

    The aim of the present research was to develop pop-up windows that motivate users and evoke a positive user experience. Several variants of achievement eliciting pop-ups were designed and tested on a real business-website. A pre-test examined the effectiveness of 24 combinations of pictures and word

  1. Immune response elicited by the oral administration of an intermediate strain of IBDV in chickens

    Directory of Open Access Journals (Sweden)

    Juan Manuel Carballeda

    2014-12-01

    Full Text Available The immune response elicited by the oral inoculation of an intermediate strain of infectious bursal disease virus was studied in chickens. A strong over expression of IL-6, IL-8, IFNα and IFNγ was observed in bursa at 3 days post inoculation together with an increase in splenic NO2 release. An influx of T-lymphocytes was also detected.

  2. Pursenality: A photo-ethnographic method for self-elicitation and co-creation

    NARCIS (Netherlands)

    Mulder, J.W.; Mulder, I.J.; Best, S.E.

    2013-01-01

    The current work introduces pursenality, a photoethnographic method for self-elicitation and cocreation, which elaborates upon current photography methods used in (design) ethnography. In total 91 bachelor students in the 6th semester participated in a purse diary study and used the pursenality meth

  3. Grounded in the landscape: Eliciting farmers' understanding of soil and soil fertility, Mali (West Africa)

    OpenAIRE

    Crane, T.

    2002-01-01

    In order to develop convincing messages and sustainable interventions, it is necessary to understand how farmers themselves perceive soil conditions and how these perceptions influence their soil management and land use decisions. This brief illustrates an ethno-scientific methodology for eliciting farmers' conceptualization of soil and soil fertility.

  4. Using a knowledge elicitation method to specify the business model of a human factors organization

    NARCIS (Netherlands)

    Schraagen, Jan Maarten; Ven, van de Josine; Hoffman, Robert R.; Moon, Brian M.

    2009-01-01

    Concept Mapping was used to structure knowledge elicitation interviews with a group of human factors specialists whose goal was to describe the business model of their Department. This novel use of cognitive task analysis to describe the business model of a human factors organization resulted in a n

  5. Differences between Spontaneous and Elicited Expressive Communication in Children with Autism

    Science.gov (United States)

    Chiang, Hsu-Min

    2009-01-01

    The purpose of this study was to investigate the differences between spontaneous and elicited expressive communication in Australian and Taiwanese children with autism who were nonverbal or had limited speech. Thirty-four children with autism (17 Australian and 17 Taiwanese children) participated in this study. Each participant was observed for 2…

  6. Scenario-based Requirements Elicitation in a Pain-teletreatment Application

    NARCIS (Netherlands)

    Widya, I.; Bults, R.G.A.; Huis in 't Veld, M.H.A.; Vollenbroek-Hutten, M.M.R.; Shishkov, B.B.; Cordeiro, J.; Ranchordas, A.

    2009-01-01

    This paper proposes a way to elicit requirements in the domain of eHealth, in particular telemedicine treatment, that is in alignment with the evidence based working practice in medicine. In collaboration with ICT developers, medical professionals co-shape the intended system, which has to support t

  7. Differential Neural Activity during Search of Specific and General Autobiographical Memories Elicited by Musical Cues

    Science.gov (United States)

    Ford, Jaclyn Hennessey; Addis, Donna Rose; Giovanello, Kelly S.

    2011-01-01

    Previous neuroimaging studies that have examined autobiographical memory specificity have utilized retrieval cues associated with prior searches of the event, potentially changing the retrieval processes being investigated. In the current study, musical cues were used to naturally elicit memories from multiple levels of specificity (i.e., lifetime…

  8. Mind-mapping: a tool for eliciting and representing knowledge held by diverse informants

    OpenAIRE

    Meier, P. S.

    2007-01-01

    Practical investigation of the use of mind-mapping at different stages of the research process: eliciting, representing and integrating knowledge. EPSRC-funded MAGNET project (developing theoretical models of gun crime to inform stakeholder decision-making about interventions). Mind-maps were particularly useful for communication within our transdisciplinary team and brainstorming, interviews and focus groups with a diverse range of stakeholders.

  9. Feedback on Feedback: Eliciting Learners' Responses to Written Feedback through Student-Generated Screencasts

    Science.gov (United States)

    Fernández-Toro, María; Furnborough, Concha

    2014-01-01

    Despite the potential benefits of assignment feedback, learners often fail to use it effectively. This study examines the ways in which adult distance learners engage with written feedback on one of their assignments. Participants were 10 undergraduates studying Spanish at the Open University, UK. Their responses to feedback were elicited by means…

  10. Prospective Elementary Mathematics Teachers' Thought Processes on a Model Eliciting Activity

    Science.gov (United States)

    Eraslan, Ali

    2012-01-01

    Mathematical model and modeling are one of the topics that have been intensively discussed in recent years. The purpose of this study is to examine prospective elementary mathematics teachers' thought processes on a model eliciting activity and reveal difficulties or blockages in the processes. The study includes forty-five seniors taking the…

  11. Early Morphological Productivity in Hungarian: Evidence from Sentence Repetition and Elicited Production

    Science.gov (United States)

    Gabor, Balint; Lukacs, Agnes

    2012-01-01

    This paper investigates early productivity of morpheme use in Hungarian children aged between 2 ; 1 and 5 ; 3. Hungarian has a rich morphology which is the core marker of grammatical functions. A new method is introduced using the novel word paradigm in a sentence repetition task with masked inflections (i.e. a disguised elicited production task).…

  12. Improving the Communication Skills of IS Developers during Requirements Elicitation Using Experiential Learning

    Science.gov (United States)

    Qurban, Mustafa H.; Austria, Richmond D.

    2009-01-01

    The improvement of communication skills among Information Systems (IS) developers can be considered as a strategy to mitigate the risk of project failure during IS design. This paper addresses issues on various communication barriers normally encountered during its requirements elicitation (RE) stage. This study aims to adopt experiential learning…

  13. Antiangiogenic Therapy Elicits Malignant Progression of Tumors to Increased Local Invasion and Distant Metastasis

    OpenAIRE

    Pàez-Ribes, Marta; Allen, Elizabeth; Hudock, James; Takeda, Takaaki; Okuyama, Hiroaki; Viñals, Francesc; Inoue, Masahiro; Bergers, Gabriele; Hanahan, Douglas; Casanovas, Oriol

    2009-01-01

    Multiple angiogenesis inhibitors have been therapeutically validated in preclinical cancer models, and several in clinical trials. Here we report that angiogenesis inhibitors targeting the VEGF pathway demonstrate antitumor effects in mouse models of pancreatic neuroendocrine carcinoma and glioblastoma but concomitantly elicit tumor adaptation and progression to stages of greater malignancy, with heightened invasiveness and in some cases increased lymphatic and distant metastasis. Increased i...

  14. Fotohistorias : Participatory photography as a methodology to elicit the life experiences of migrants

    NARCIS (Netherlands)

    Yefimova, Katya; Neils, Moriah; Newell, Bryce; Gomez, Ricardo

    2015-01-01

    We present the results of a participatory photography approach to eliciting the life experiences and worldviews of undocumented Hispanic migrants at the U.S.-Mexico border. While offering a space for reflection, Fotohistorias explores how undocumented migrants at the U.S.-Mexico border express their

  15. Eliciting, Identifying, Interpreting, and Responding to Students' Ideas: Teacher Candidates' Growth in Formative Assessment Practices

    Science.gov (United States)

    Gotwals, Amelia Wenk; Birmingham, Daniel

    2016-01-01

    With the goal of helping teacher candidates become well-started beginners, it is important that methods courses in teacher education programs focus on high-leverage practices. Using responsive teaching practices, specifically eliciting, identifying, interpreting, and responding to students' science ideas (i.e., formative assessment), can be used…

  16. Assessing Measurement Invariance for Spanish Sentence Repetition and Morphology Elicitation Tasks

    Science.gov (United States)

    Kapantzoglou, Maria; Thompson, Marilyn S.; Gray, Shelley; Restrepo, M. Adelaida

    2016-01-01

    Purpose: The purpose of this study was to evaluate evidence supporting the construct validity of two grammatical tasks (sentence repetition, morphology elicitation) included in the Spanish Screener for Language Impairment in Children (Restrepo, Gorin, & Gray, 2013). We evaluated if the tasks measured the targeted grammatical skills in the same…

  17. Identification and Characterization of Ixodes scapularis Antigens That Elicit Tick Immunity Using Yeast Surface Display

    NARCIS (Netherlands)

    T.J. Schuijt; S. Narasimhan; S. Daffre; K. Deponte; J.W.R. Hovius; C. van 't Veer; T. van der Poll; K. Bakhtiari; J.C.M. Meijers; E.T. Boder; A.P. van Dam; E. Fikrig

    2011-01-01

    Repeated exposure of rabbits and other animals to ticks results in acquired resistance or immunity to subsequent tick bites and is partially elicited by antibodies directed against tick antigens. In this study we demonstrate the utility of a yeast surface display approach to identify tick salivary a

  18. Deriving Childhood Temperament Measures from Emotion-Eliciting Behavioral Episodes: Scale Construction and Initial Validation

    Science.gov (United States)

    Gagne, Jeffrey R.; Van Hulle, Carol A.; Aksan, Nazan; Essex, Marilyn J.; Goldsmith, H. Hill

    2011-01-01

    The authors describe the development and initial validation of a home-based version of the Laboratory Temperament Assessment Battery (Lab-TAB), which was designed to assess childhood temperament with a comprehensive series of emotion-eliciting behavioral episodes. This article provides researchers with general guidelines for assessing specific…

  19. Muscular reflexes elicited by electrical stimulation of the anterior cruciate ligament in humans

    DEFF Research Database (Denmark)

    Dyhre-Poulsen, P; Krogsgaard, M R

    2000-01-01

    Anterior cruciate ligament (ACL)-deficient knees have impaired proprioception, and, although mechanoreceptors have been found in the ACL, the existence of a reflex elicited from these receptors has not been directly demonstrated in humans. In eight patients that underwent knee arthroscopy and had...

  20. Lumichrome and riboflavin are two novel symbiotic signals eliciting developmental changes in both monocot and dicot plant species

    Directory of Open Access Journals (Sweden)

    Felix Dapare Dakora

    2015-09-01

    Full Text Available Lumichrome and riboflavin are novel molecules from rhizobial exudates that stimulate plant growth. Developmental changes elicited by lumichrome at very low nanomolar concentrations (5 nM include early initiation of trifoliate leaves, expansion of unifoliate and trifoliate leaves, increased stem elongation and leaf area, and consequently greater biomass accumulation in monocots and dicots. However, higher lumichrome concentration (50 nM depressed root development and reduced growth of unifoliate and second trifoliate leaves. Applying either 10 nM lumichrome, 10 nM ABA, or 10 ml of infective rhizobial cells (0.2 OD600 to roots of monocots and dicots for 44 h produced identical effects, which included decreased stomatal conductance and leaf transpiration in Bambara groundnut, soybean and maize, increased stomatal conductance and transpiration in cowpea and lupin, and elevated root respiration in maize (19% by rhizobia and 20% by lumichrome. Extracellular exudation of lumichrome, riboflavin and IAA was greater in N2-fixing rhizobia than non-fixing bacteria, indicating their role as symbiotic signals. Xylem concentration of lumichrome in cowpea and soybean was greater in plants inoculated with infective rhizobia and treated with lumichrome (61.2 µmol lumichrome.ml-1 sap, followed by uninoculated plants receiving lumichrome (41.12 µmol lumichrome.ml-1 sap, and lowest in uninoculated, lumichrome-free plants (26.8 µmol lumichrome.ml-1 sap. Overall, soybean showed greater xylem concentration of lumichrome and a correspondingly increased accumulation in leaves relative to cowpea. As a result, soybean exhibited dramatic developmental changes than cowpea. Taken together, lumichrome and riboflavin secreted by soil rhizobia function as environmental cues for sensing stress. The fact that exogenous application of ABA to plant roots caused the same effect as lumichrome on stomatal functioning suggests molecular cross-talk in plant response to environmental

  1. The Divergent CD8+ T Cell Adjuvant Properties of LT-IIb and LT-IIc, Two Type II Heat-Labile Enterotoxins, Are Conferred by Their Ganglioside-Binding B Subunits.

    Directory of Open Access Journals (Sweden)

    John C Hu

    Full Text Available Poor immune responses elicited by vaccine antigens can be enhanced by the use of appropriate adjuvants. Type II heat-labile enterotoxins (HLT produced by Escherichia coli are extremely potent adjuvants that augment both humoral and cellular immunity to co-administered antigens. Recent findings demonstrate that LT-IIb and LT-IIc, two type II HLT adjuvants, exhibit potent, yet distinguishable CD8(+ T cell adjuvant properties. While LT-IIc elicits a robust and rapid response at one week after administration, LT-IIb engenders a more gradual and slower expansion of antigen-specific CD8(+ T cells that correlates with improved immunity. The variations in immune effects elicited by the HLT adjuvants have been generally attributed to their highly divergent B subunits that mediate binding to various gangliosides on cell surfaces. Yet, HLT adjuvants with point mutations in the B subunit that significantly alter ganglioside binding retain similar adjuvant functions. Therefore, the contribution of the B subunits to adjuvanticity remains unclear. To investigate the influence of the B subunits on the enhancement of immune responses by LT-IIb and LT-IIc, chimeric HLT were engineered in which the B subunits of the two adjuvants were exchanged. Comparing the immune potentiating characteristics of both native and chimeric HLT adjuvants, it was found that not all the adjuvant characteristics of the HLT adjuvants were modulated by the respective B subunits. Specifically, the differences in the CD8(+ T cell kinetics and protective responses elicited by LT-IIb and LT-IIc did indeed followed their respective B subunits. However, induction of IL-1 from macrophages and the capacity to intoxicate cells in a mouse Y1 adrenal cell bioassay did not correlate with the B subunits. Therefore, it is likely that additional factors other than the B subunits contribute to the effects elicited by the HLT adjuvants.

  2. Safety Risk Knowledge Elicitation in Support of Aeronautical R and D Portfolio Management: A Case Study

    Science.gov (United States)

    Shih, Ann T.; Ancel, Ersin; Jones, Sharon Monica; Reveley, Mary S.; Luxhoj, James T.

    2012-01-01

    Aviation is a problem domain characterized by a high level of system complexity and uncertainty. Safety risk analysis in such a domain is especially challenging given the multitude of operations and diverse stakeholders. The Federal Aviation Administration (FAA) projects that by 2025 air traffic will increase by more than 50 percent with 1.1 billion passengers a year and more than 85,000 flights every 24 hours contributing to further delays and congestion in the sky (Circelli, 2011). This increased system complexity necessitates the application of structured safety risk analysis methods to understand and eliminate where possible, reduce, and/or mitigate risk factors. The use of expert judgments for probabilistic safety analysis in such a complex domain is necessary especially when evaluating the projected impact of future technologies, capabilities, and procedures for which current operational data may be scarce. Management of an R&D product portfolio in such a dynamic domain needs a systematic process to elicit these expert judgments, process modeling results, perform sensitivity analyses, and efficiently communicate the modeling results to decision makers. In this paper a case study focusing on the application of an R&D portfolio of aeronautical products intended to mitigate aircraft Loss of Control (LOC) accidents is presented. In particular, the knowledge elicitation process with three subject matter experts who contributed to the safety risk model is emphasized. The application and refinement of a verbal-numerical scale for conditional probability elicitation in a Bayesian Belief Network (BBN) is discussed. The preliminary findings from this initial step of a three-part elicitation are important to project management practitioners as they illustrate the vital contribution of systematic knowledge elicitation in complex domains.

  3. A methodology for eliciting, representing, and analysing stakeholder knowledge for decision making on complex socio-ecological systems: from cognitive maps to agent-based models.

    Science.gov (United States)

    Elsawah, Sondoss; Guillaume, Joseph H A; Filatova, Tatiana; Rook, Josefine; Jakeman, Anthony J

    2015-03-15

    This paper aims to contribute to developing better ways for incorporating essential human elements in decision making processes for modelling of complex socio-ecological systems. It presents a step-wise methodology for integrating perceptions of stakeholders (qualitative) into formal simulation models (quantitative) with the ultimate goal of improving understanding and communication about decision making in complex socio-ecological systems. The methodology integrates cognitive mapping and agent based modelling. It cascades through a sequence of qualitative/soft and numerical methods comprising: (1) Interviews to elicit mental models; (2) Cognitive maps to represent and analyse individual and group mental models; (3) Time-sequence diagrams to chronologically structure the decision making process; (4) All-encompassing conceptual model of decision making, and (5) computational (in this case agent-based) Model. We apply the proposed methodology (labelled ICTAM) in a case study of viticulture irrigation in South Australia. Finally, we use strengths-weakness-opportunities-threats (SWOT) analysis to reflect on the methodology. Results show that the methodology leverages the use of cognitive mapping to capture the richness of decision making and mental models, and provides a combination of divergent and convergent analysis methods leading to the construction of an Agent Based Model.

  4. A methodology for eliciting, representing, and analysing stakeholder knowledge for decision making on complex socio-ecological systems: from cognitive maps to agent-based models.

    Science.gov (United States)

    Elsawah, Sondoss; Guillaume, Joseph H A; Filatova, Tatiana; Rook, Josefine; Jakeman, Anthony J

    2015-03-15

    This paper aims to contribute to developing better ways for incorporating essential human elements in decision making processes for modelling of complex socio-ecological systems. It presents a step-wise methodology for integrating perceptions of stakeholders (qualitative) into formal simulation models (quantitative) with the ultimate goal of improving understanding and communication about decision making in complex socio-ecological systems. The methodology integrates cognitive mapping and agent based modelling. It cascades through a sequence of qualitative/soft and numerical methods comprising: (1) Interviews to elicit mental models; (2) Cognitive maps to represent and analyse individual and group mental models; (3) Time-sequence diagrams to chronologically structure the decision making process; (4) All-encompassing conceptual model of decision making, and (5) computational (in this case agent-based) Model. We apply the proposed methodology (labelled ICTAM) in a case study of viticulture irrigation in South Australia. Finally, we use strengths-weakness-opportunities-threats (SWOT) analysis to reflect on the methodology. Results show that the methodology leverages the use of cognitive mapping to capture the richness of decision making and mental models, and provides a combination of divergent and convergent analysis methods leading to the construction of an Agent Based Model. PMID:25622296

  5. Horizontally acquired genes in early-diverging pathogenic fungi enable the use of host nucleosides and nucleotides.

    Science.gov (United States)

    Alexander, William G; Wisecaver, Jennifer H; Rokas, Antonis; Hittinger, Chris Todd

    2016-04-12

    Horizontal gene transfer (HGT) among bacteria, archaea, and viruses is widespread, but the extent of transfers from these lineages into eukaryotic organisms is contentious. Here we systematically identify hundreds of genes that were likely acquired horizontally from a variety of sources by the early-diverging fungal phyla Microsporidia and Cryptomycota. Interestingly, the Microsporidia have acquired via HGT several genes involved in nucleic acid synthesis and salvage, such as those encoding thymidine kinase (TK), cytidylate kinase, and purine nucleotide phosphorylase. We show that these HGT-derived nucleic acid synthesis genes tend to function at the interface between the metabolic networks of the host and pathogen. Thus, these genes likely play vital roles in diversifying the useable nucleic acid components available to the intracellular parasite, often through the direct capture of resources from the host. Using an in vivo viability assay, we also demonstrate that one of these genes, TK, encodes an enzyme that is capable of activating known prodrugs to their active form, which suggests a possible treatment route for microsporidiosis. We further argue that interfacial genes with well-understood activities, especially those horizontally transferred from bacteria or viruses, could provide medical treatments for microsporidian infections. PMID:27035945

  6. Rumen cellulosomics: divergent fiber-degrading strategies revealed by comparative genome-wide analysis of six ruminococcal strains.

    Directory of Open Access Journals (Sweden)

    Bareket Dassa

    Full Text Available A complex community of microorganisms is responsible for efficient plant cell wall digestion by many herbivores, notably the ruminants. Understanding the different fibrolytic mechanisms utilized by these bacteria has been of great interest in agricultural and technological fields, reinforced more recently by current efforts to convert cellulosic biomass to biofuels.Here, we have used a bioinformatics-based approach to explore the cellulosome-related components of six genomes from two of the primary fiber-degrading bacteria in the rumen: Ruminococcus flavefaciens (strains FD-1, 007c and 17 and Ruminococcus albus (strains 7, 8 and SY3. The genomes of two of these strains are reported for the first time herein. The data reveal that the three R. flavefaciens strains encode for an elaborate reservoir of cohesin- and dockerin-containing proteins, whereas the three R. albus strains are cohesin-deficient and encode mainly dockerins and a unique family of cell-anchoring carbohydrate-binding modules (family 37.Our comparative genome-wide analysis pinpoints rare and novel strain-specific protein architectures and provides an exhaustive profile of their numerous lignocellulose-degrading enzymes. This work provides blueprints of the divergent cellulolytic systems in these two prominent fibrolytic rumen bacterial species, each of which reflects a distinct mechanistic model for efficient degradation of cellulosic biomass.

  7. Divergent responses of methanogenic archaeal communities in two rice cultivars to elevated ground-level O3.

    Science.gov (United States)

    Zhang, Jianwei; Tang, Haoye; Zhu, Jianguo; Lin, Xiangui; Feng, Youzhi

    2016-06-01

    Inhibitive effect of elevated ground-level ozone (O3) on paddy methane (CH4) emission varies with rice cultivars. However, little information is available on its microbial mechanism. For this purpose, the responses of methane-metabolizing microorganisms, methanogenic archaea and methanotrophic bacteria to O3 pollution were investigated in the O3-tolerant (YD6) and the O3-sensitive (IIY084) cultivars at two rice growth stages in Free Air Concentration Elevation of O3 (O3-FACE) system of China. It was found that O3 pollution didn't change the abundances of Type I and Type II methanotrophic bacteria at two rice stages. For methanogenic archaea, their abundances in both cultivars were decreased by O3 pollution at the tillering stage. Furthermore, a greater negative influence on methanogenic archaeal community was observed on IIY084 than on YD6: at tillering stage, the alpha diversity indices of methanogenic archaeal community in IIY084 was decreased to a greater extent than in YD6; IIY084 shifted methanogenic archaeal community composition and decreased the abundances and the diversities of Methanosarcinaceae and Methanosaetaceae as well as the abundance of Methanomicrobiales, while the diversity of Methanocellaceae were increased in YD6. These findings indicate that the variations in the responses of paddy CH4 emission to O3 pollution between cultivars could result from the divergent responses of their methanogenic archaea. PMID:26895536

  8. Physico-chemical factors and bacteria in fish ponds

    OpenAIRE

    Jun, X.; Xiuzheng, F.; Tongbing, Y.

    2000-01-01

    Analyses of pond water and mud samples show that nitrifying bacteria (including ammonifying bacteria, nitrite bacteria, nitrobacteria and denitrifying bacteria) are in general closely correlated with various physico-chemical factors, ammonifying bacteria are mainly correlated with dissolved oxygen; denitrifying bacteria are inversely correlated with phosphorus; nitrite bacteria are closely correlated with nitrites, nitrobacteria are inversely correlated with ammoniac nitrogen. The nitrifying ...

  9. Gene duplication and divergence affecting drug content in Cannabis sativa.

    Science.gov (United States)

    Weiblen, George D; Wenger, Jonathan P; Craft, Kathleen J; ElSohly, Mahmoud A; Mehmedic, Zlatko; Treiber, Erin L; Marks, M David

    2015-12-01

    Cannabis sativa is an economically important source of durable fibers, nutritious seeds, and psychoactive drugs but few economic plants are so poorly understood genetically. Marijuana and hemp were crossed to evaluate competing models of cannabinoid inheritance and to explain the predominance of tetrahydrocannabinolic acid (THCA) in marijuana compared with cannabidiolic acid (CBDA) in hemp. Individuals in the resulting F2 population were assessed for differential expression of cannabinoid synthase genes and were used in linkage mapping. Genetic markers associated with divergent cannabinoid phenotypes were identified. Although phenotypic segregation and a major quantitative trait locus (QTL) for the THCA/CBDA ratio were consistent with a simple model of codominant alleles at a single locus, the diversity of THCA and CBDA synthase sequences observed in the mapping population, the position of enzyme coding loci on the map, and patterns of expression suggest multiple linked loci. Phylogenetic analysis further suggests a history of duplication and divergence affecting drug content. Marijuana is distinguished from hemp by a nonfunctional CBDA synthase that appears to have been positively selected to enhance psychoactivity. An unlinked QTL for cannabinoid quantity may also have played a role in the recent escalation of drug potency.

  10. Spontaneous eye blinks during creative task correlate with divergent processing.

    Science.gov (United States)

    Ueda, Yoshiyuki; Tominaga, Atsuko; Kajimura, Shogo; Nomura, Michio

    2016-07-01

    Creativity consists of divergent and convergent thinking, with both related to individual eye blinks at rest. To assess underlying mechanisms between eye blinks and traditional creativity tasks, we investigated the relationship between creativity performance and eye blinks at rest and during tasks. Participants performed an alternative uses and remote association task while eye blinks were recorded. Results showed that the relationship between eye blinks at rest and creativity performance was compatible with those of previous research. Interestingly, we found that the generation of ideas increased as a function of eye blink number during the alternative uses task. On the other hand, during the remote association task, accuracy was independent of eye blink number during the task, but response time increased with it. Moreover, eye blink changes in participants who responded quickly during the remote association task were different depending on their resting state eye blinks; that is, participants with many eye blinks during rest showed little increasing eye blinks and achieved solutions quickly. Positive correlations between eye blinks during creative tasks and yielding ideas on the alternative uses task and response time on the remote association task suggest that eye blinks during creativity tasks relate to divergent thinking processes such as conceptual reorganization. PMID:25863791

  11. Distance-dependent patterns of molecular divergences in Tuatara mitogenomes.

    Science.gov (United States)

    Subramanian, Sankar; Mohandesan, Elmira; Millar, Craig D; Lambert, David M

    2015-01-01

    Population genetic models predict that populations that are geographically close to each other are expected to be genetically more similar to each other compared to those that are widely separate. However the patterns of relationships between geographic distance and molecular divergences at neutral and constrained regions of the genome are unclear. We attempted to clarify this relationship by sequencing complete mitochondrial genomes of the relic species Tuatara (Sphenodon punctatus) from ten offshore islands of New Zealand. We observed a positive relationship that showed a proportional increase in the neutral diversity at synonymous sites (dS), with increasing geographical distance. In contrast we showed that diversity at evolutionarily constrained sites (dC) was elevated in the case of comparisons involving closely located populations. Conversely diversity was reduced in the case of comparisons between distantly located populations. These patterns were confirmed by a significant negative relationship between the ratio of dC/dS and geographic distance. The observed high dC/dS could be explained by the abundance of deleterious mutations in comparisons involving closely located populations, due to the recent population divergence times. Since distantly related populations were separated over long periods of time, deleterious mutations might have been removed by purifying selection. PMID:25731894

  12. Factor analysis models via I-divergence optimization.

    Science.gov (United States)

    Finesso, Lorenzo; Spreij, Peter

    2016-09-01

    Given a positive definite covariance matrix [Formula: see text] of dimension n, we approximate it with a covariance of the form [Formula: see text], where H has a prescribed number [Formula: see text] of columns and [Formula: see text] is diagonal. The quality of the approximation is gauged by the I-divergence between the zero mean normal laws with covariances [Formula: see text] and [Formula: see text], respectively. To determine a pair (H, D) that minimizes the I-divergence we construct, by lifting the minimization into a larger space, an iterative alternating minimization algorithm (AML) à la Csiszár-Tusnády. As it turns out, the proper choice of the enlarged space is crucial for optimization. The convergence of the algorithm is studied, with special attention given to the case where D is singular. The theoretical properties of the AML are compared to those of the popular EM algorithm for exploratory factor analysis. Inspired by the ECME (a Newton-Raphson variation on EM), we develop a similar variant of AML, called ACML, and in a few numerical experiments, we compare the performances of the four algorithms. PMID:26608962

  13. Coherence and Divergence of Megatrends in Science and Engineering

    International Nuclear Information System (INIS)

    Scientific discoveries and technological innovations are at the core of human endeavor, and it is estimated that their role will only increase in time. Such advancements evolve in coherence, with areas of confluence and temporary divergences, which bring synergism and that stimulate further developments following in average an exponential growth. Six increasingly interconnected megatrends are perceived as dominating the scene for the next decades: (a) information and computing, (b) nanoscale science and engineering (S and E), (c) biology and bio-environmental approaches, (d) medical sciences and enhancing human physical capabilities, (e) cognitive sciences and enhancing intellectual abilities, and (f) collective behavior and system approach.This paper presents a perspective on the process of identification, planning and program implementation of S and E megatrends, with illustration for the US research initiative on nanoscale science, engineering, and technology. The interplay between coherence and divergence, leading to unifying science and converging technologies, does not develop only among simultaneous scientific trends but also along time and across geopolitical boundaries. There is no single way of development of S and E, and here is the role of taking visionary measures. Societal implication scientists need to be involved from the conceptual phase of a program responding to a S and E megatrend

  14. Effect of fringe divergence in fluid acceleration measurement using LDA

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Se Jong; Sung, Hyung Jin [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Nobach, Holger; Tropea, Cam [Technische Universitat Darmstadt, Darmstadt (Germany)

    2004-07-01

    The laser Doppler technique is well-established as a velocity measurement technique of high precision for flow velocity. Recently, the laser Doppler technique has also been used to measure acceleration of fluid particles. Acceleration is interesting from a fluid mechanics point of view, since the Navier Stokes equations, specifically the left-hand-side, are formulated in terms of fluid acceleration. Further, there are several avenues to estimating the dissipation rate using the acceleration. However such measurements place additional demands on the design of the optical system; in particular fringe non-uniformity must be held below about 0.0001 to avoid systematic errors. Relations expressing fringe divergence as a function of the optical parameters of the system have been given in the literature; however, direct use of these formulae to minimize fringe divergence lead either to very large measurement volumes or to extremely high intersection angles. This dilemma can be resolved by using an off-axis receiving arrangement, in which the measurement volume is truncated by a pinhole in front of the detection plane. In the present study an optical design study is performed for optimizing laser Doppler systems for fluid acceleration measurements. This is followed by laboratory validation using a round free jet and a stagnation flow, two flows in which either fluid acceleration has been previously measured or in which the acceleration is known analytically. A 90 degree off-axis receiving angle is used with a pinhole or a slit.

  15. Transcriptional divergence and conservation of human and mouse erythropoiesis.

    Science.gov (United States)

    Pishesha, Novalia; Thiru, Prathapan; Shi, Jiahai; Eng, Jennifer C; Sankaran, Vijay G; Lodish, Harvey F

    2014-03-18

    Mouse models have been used extensively for decades and have been instrumental in improving our understanding of mammalian erythropoiesis. Nonetheless, there are several examples of variation between human and mouse erythropoiesis. We performed a comparative global gene expression study using data from morphologically identical stage-matched sorted populations of human and mouse erythroid precursors from early to late erythroblasts. Induction and repression of major transcriptional regulators of erythropoiesis, as well as major erythroid-important proteins, are largely conserved between the species. In contrast, at a global level we identified a significant extent of divergence between the species, both at comparable stages and in the transitions between stages, especially for the 500 most highly expressed genes during development. This suggests that the response of multiple developmentally regulated genes to key erythroid transcriptional regulators represents an important modification that has occurred in the course of erythroid evolution. In developing a systematic framework to understand and study conservation and divergence between human and mouse erythropoiesis, we show how mouse models can fail to mimic specific human diseases and provide predictions for translating findings from mouse models to potential therapies for human disease.

  16. Gene duplication and divergence affecting drug content in Cannabis sativa.

    Science.gov (United States)

    Weiblen, George D; Wenger, Jonathan P; Craft, Kathleen J; ElSohly, Mahmoud A; Mehmedic, Zlatko; Treiber, Erin L; Marks, M David

    2015-12-01

    Cannabis sativa is an economically important source of durable fibers, nutritious seeds, and psychoactive drugs but few economic plants are so poorly understood genetically. Marijuana and hemp were crossed to evaluate competing models of cannabinoid inheritance and to explain the predominance of tetrahydrocannabinolic acid (THCA) in marijuana compared with cannabidiolic acid (CBDA) in hemp. Individuals in the resulting F2 population were assessed for differential expression of cannabinoid synthase genes and were used in linkage mapping. Genetic markers associated with divergent cannabinoid phenotypes were identified. Although phenotypic segregation and a major quantitative trait locus (QTL) for the THCA/CBDA ratio were consistent with a simple model of codominant alleles at a single locus, the diversity of THCA and CBDA synthase sequences observed in the mapping population, the position of enzyme coding loci on the map, and patterns of expression suggest multiple linked loci. Phylogenetic analysis further suggests a history of duplication and divergence affecting drug content. Marijuana is distinguished from hemp by a nonfunctional CBDA synthase that appears to have been positively selected to enhance psychoactivity. An unlinked QTL for cannabinoid quantity may also have played a role in the recent escalation of drug potency. PMID:26189495

  17. Marker-aided genetic divergence analysis in Brassica

    Indian Academy of Sciences (India)

    V. Arunachalam; Shefali Verma; V. Sujata; K. V. Prabhu

    2005-08-01

    Genetic divergence was evaluated in 31 breeding lines from four Brassica species using Mahalanobis’ $D^{2}$. A new method of grouping using $D^{2}$ values was used to group the 31 lines, based on diagnostic morphological traits (called morphoqts). Isozyme variation of the individual enzymes esterase and glutamate oxaloacetate was quantified by five parameters (called isoqts) developed earlier. Grouping by the same method was also done based on the isoqts, and the grouping by isozymes was compared with that by morphoqts. Overall, there was an agreement of 73% suggesting that isoqts can be used in the choice of parents and also first stage selection of segregants in the laboratory. It was suggested that such an exercise would help to take care of season-bound and field-related problems of breeding. The new isozyme QTs, within lane variance of relative mobility and relative absorption, accounted for about 50% of the total divergence. The utility of the new method and isoqts in cost-effective breeding were highlighted.

  18. Smokeless Tobacco May Contain Potentially Harmful Bacteria

    Science.gov (United States)

    ... 160769.html Smokeless Tobacco May Contain Potentially Harmful Bacteria Infections, diarrhea and vomiting are possible consequences, FDA ... products can harbor several species of potentially harmful bacteria, researchers warn. Two types in particular -- Bacillus licheniformis ...

  19. Quantifying the evolutionary divergence of protein structures: the role of function change and function conservation.

    Science.gov (United States)

    Pascual-García, Alberto; Abia, David; Méndez, Raúl; Nido, Gonzalo S; Bastolla, Ugo

    2010-01-01

    The molecular clock hypothesis, stating that protein sequences diverge in evolution by accumulating amino acid substitutions at an almost constant rate, played a major role in the development of molecular evolution and boosted quantitative theories of evolutionary change. These studies were extended to protein structures by the seminal paper by Chothia and Lesk, which established the approximate proportionality between structure and sequence divergence. Here we analyse how function influences the relationship between sequence and structure divergence, studying four large superfamilies of evolutionarily related proteins: globins, aldolases, P-loop and NADP-binding. We introduce the contact divergence, which is more consistent with sequence divergence than previously used structure divergence measures. Our main findings are: (1) Small structure and sequence divergences are proportional, consistent with the molecular clock. Approximate validity of the clock is also supported by the analysis of the clustering coefficient of structure similarity networks. (2) Functional constraints strongly limit the structure divergence of proteins performing the same function and may allow to identify incomplete or wrong functional annotations. (3) The rate of structure versus sequence divergence is larger for proteins performing different functions than for proteins performing the same function. We conjecture that this acceleration is due to positive selection for new functions. Accelerations in structure divergence are also suggested by the analysis of the clustering coefficient. (4) For low sequence identity, structural diversity explodes. We conjecture that this explosion is related to functional diversification. (5) Large indels are almost always associated with function changes.

  20. Molecular evolution and sequence divergence of plant chalcone synthase and chalcone synthase-Like genes.

    Science.gov (United States)

    Han, Yingying; Zhao, Wenwen; Wang, Zhicui; Zhu, Jingying; Liu, Qisong

    2014-06-01

    Plant chalcone synthase (CHS) and CHS-Like (CHSL) proteins are polyketide synthases. In this study, we evaluated the molecular evolution of this gene family using representative types of CHSL genes, including stilbene synthase (STS), 2-pyrone synthase (2-PS), bibenzyl synthase (BBS), acridone synthase (ACS), biphenyl synthase (BIS), benzalacetone synthase, coumaroyl triacetic acid synthase (CTAS), and benzophenone synthase (BPS), along with their CHS homologs from the same species of both angiosperms and gymnosperms. A cDNA-based phylogeny indicated that CHSLs had diverse evolutionary patterns. STS, ACS, and 2-PS clustered with CHSs from the same species (late diverged pattern), while CTAS, BBS, BPS, and BIS were distant from their CHS homologs (early diverged pattern). The amino-acid phylogeny suggested that CHS and CHSL proteins formed clades according to enzyme function. The CHSs and CHSLs from Polygonaceae and Arachis had unique evolutionary histories. Synonymous mutation rates were lower in late diverged CHSLs than in early diverged ones, indicating that gene duplications occurred more recently in late diverged CHSLs than in early diverged ones. Relative rate tests proved that late diverged CHSLs had unequal rates to CHSs from the same species when using fatty acid synthase, which evolved from the common ancestor with the CHS superfamily, as the outgroup, while the early diverged lineages had equal rates. This indicated that late diverged CHSLs experienced more frequent mutation than early diverged CHSLs after gene duplication, allowing obtaining new functions in relatively short period of time.

  1. Genome divergence during evolutionary diversification as revealed in replicate lake-stream stickleback population pairs.

    Science.gov (United States)

    Roesti, Marius; Hendry, Andrew P; Salzburger, Walter; Berner, Daniel

    2012-06-01

    Evolutionary diversification is often initiated by adaptive divergence between populations occupying ecologically distinct environments while still exchanging genes. The genetic foundations of this divergence process are largely unknown and are here explored through genome scans in multiple independent lake-stream population pairs of threespine stickleback. We find that across the pairs, overall genomic divergence is associated with the magnitude of divergence in phenotypes known to be under divergent selection. Along this same axis of increasing diversification, genomic divergence becomes increasingly biased towards the centre of chromosomes as opposed to the peripheries. We explain this pattern by within-chromosome variation in the physical extent of hitchhiking, as recombination is greatly reduced in chromosome centres. Correcting for this effect suggests that a great number of genes distributed widely across the genome are involved in the divergence into lake vs. stream habitats. Analyzing additional allopatric population pairs, however, reveals that strong divergence in some genomic regions has been driven by selection unrelated to lake-stream ecology. Our study highlights a major contribution of large-scale variation in recombination rate to generating heterogeneous genomic divergence and indicates that elucidating the genetic basis of adaptive divergence might be more challenging than currently recognized.

  2. Genome divergence during evolutionary diversification as revealed in replicate lake-stream stickleback population pairs.

    Science.gov (United States)

    Roesti, Marius; Hendry, Andrew P; Salzburger, Walter; Berner, Daniel

    2012-06-01

    Evolutionary diversification is often initiated by adaptive divergence between populations occupying ecologically distinct environments while still exchanging genes. The genetic foundations of this divergence process are largely unknown and are here explored through genome scans in multiple independent lake-stream population pairs of threespine stickleback. We find that across the pairs, overall genomic divergence is associated with the magnitude of divergence in phenotypes known to be under divergent selection. Along this same axis of increasing diversification, genomic divergence becomes increasingly biased towards the centre of chromosomes as opposed to the peripheries. We explain this pattern by within-chromosome variation in the physical extent of hitchhiking, as recombination is greatly reduced in chromosome centres. Correcting for this effect suggests that a great number of genes distributed widely across the genome are involved in the divergence into lake vs. stream habitats. Analyzing additional allopatric population pairs, however, reveals that strong divergence in some genomic regions has been driven by selection unrelated to lake-stream ecology. Our study highlights a major contribution of large-scale variation in recombination rate to generating heterogeneous genomic divergence and indicates that elucidating the genetic basis of adaptive divergence might be more challenging than currently recognized. PMID:22384978

  3. The dynamics of apoplast phenolics in tobacco leaves following inoculation with bacteria

    Directory of Open Access Journals (Sweden)

    Con Jacyn Baker

    2015-08-01

    Full Text Available This study demonstrates that the accumulation of apoplastic phenolics is stimulated in planta in response to bacterial inoculation. Past studies have shown that levels of extracellular phenolics are elicited in plant cell suspensions in response to bacteria, and that tomato plants infected with viroids showed changes in apoplastic phenolics. The method described here monitored changes in apoplastic phenolics in tobacco leaves following bacterial inoculation of the same tissue. Inoculation with a saprophyte, Pseudomonas fluorescens, which does not cause visible symptoms or physical damage, was used to elicit phenolics and examine the effects of variable parameters on phenolic composition. Location of the inoculation on the leaf, position or developmental age of the leaf on the plant, and inoculum concentration were standardized for further experiments. The patterns of phenolic change in the apoplast were compared for tobacco inoculated with P. syringae pathovars, pv. syringae, which causes a resistant HR reaction within 15 h, and pv. tabaci, which causes a susceptible reaction with delayed visible symptoms. Both pathogens elicited lower increased levels of acetosyringone compared to the saprophyte, P. fluorescens but had greatly increased levels of the chlorogenic acid derivatives. The latter metabolites appear to have come from the intracellular stores, which could

  4. Characterization of a genomic divergence island between black-and-yellow and gopher Sebastes rockfishes.

    Science.gov (United States)

    Buonaccorsi, Vincent P; Narum, Shawn R; Karkoska, Kristine A; Gregory, Steven; Deptola, Travis; Weimer, Alexander B

    2011-06-01

    Islands of high genomic divergence that contain genes of evolutionary significance may form between diverging species. The gopher rockfish, Sebastes carnatus, and black-and-yellow rockfish, S. chrysomelas, are sympatrically distributed temperate marine species inhabiting rocky reefs and kelp forests on the west coast of the United States. Prior studies documented low levels of genetic divergence between the two species, except at a single microsatellite locus that displayed high divergence, Sra.7-2. To better characterize genome wide divergence, we scored 25 additional microsatellite loci. Mean neutral divergence between species (F(ST) = 0.01) changed little from prior estimates. Sra.7-2 continued to be an extreme divergence outlier. Five novel microsatellites within ± 15 kb of Sra.7-2 were characterized. High divergence, consistently low diversity in S. chrysomelas, and linkage disequilibrium were detected at these loci, suggesting the influence of recent selection. However, coalescent modelling of divergence at neutral and Sra.7-2 regions showed that initial divergence at Sra.7-2 was ancient, likely predating divergence at neutral regions. It is therefore unlikely that Sra.7-2 divergence represents solely recent ecological divergence within one species and may represent the action of recurrent selection. Introgressive gene flow (2N(E) m) was much higher (>1) at neutral than Sra.7-2 regions (<1) despite evidence that two S. carnatus individuals have recently mixed ancestry at the Sra.7-2 region. The Sra.7-2 genomic region is likely one of several regions containing genes involved in initiating and maintaining species integrity. Completion of the final stages of speciation appears to be a slow and ongoing process for these species. PMID:21557784

  5. Genetics of Lactic Acid Bacteria

    Science.gov (United States)

    Zagorec, Monique; Anba-Mondoloni, Jamila; Coq, Anne-Marie Crutz-Le; Champomier-Vergès, Marie-Christine

    Many meat (or fish) products, obtained by the fermentation of meat originating from various animals by the flora that naturally contaminates it, are part of the human diet since millenaries. Historically, the use of bacteria as starters for the fermentation of meat, to produce dry sausages, was thus performed empirically through the endogenous micro-biota, then, by a volunteer addition of starters, often performed by back-slopping, without knowing precisely the microbial species involved. It is only since about 50 years that well defined bacterial cultures have been used as starters for the fermentation of dry sausages. Nowadays, the indigenous micro-biota of fermented meat products is well identified, and the literature is rich of reports on the identification of lactic acid bacteria (LAB) present in many traditional fermented products from various geographical origin, obtained without the addition of commercial starters (See Talon, Leroy, & Lebert, 2007, and references therein).

  6. Aggregation Patterns in Stressed Bacteria

    CERN Document Server

    Tsimring, L S; Aranson, I S; Ben-Jacob, E; Cohen, I; Shochet, O; Tsimring, Lev; Levine, Herbert; Aranson, Igor; Ben-Jacob, Eshel; Cohen, Inon; Shochet, Ofer

    1995-01-01

    We study the formation of spot patterns seen in a variety of bacterial species when the bacteria are subjected to oxidative stress due to hazardous byproducts of respiration. Our approach consists of coupling the cell density field to a chemoattractant concentration as well as to nutrient and waste fields. The latter serves as a triggering field for emission of chemoattractant. Important elements in the proposed model include the propagation of a front of motile bacteria radially outward form an initial site, a Turing instability of the uniformly dense state and a reduction of motility for cells sufficiently far behind the front. The wide variety of patterns seen in the experiments is explained as being due the variation of the details of the initiation of the chemoattractant emission as well as the transition to a non-motile phase.

  7. Dissipative Shocks behind Bacteria Gliding

    CERN Document Server

    Virga, Epifanio G

    2014-01-01

    Gliding is a means of locomotion on rigid substrates utilized by a number of bacteria includingmyxobacteria and cyanobacteria. One of the hypotheses advanced to explain this motility mechanism hinges on the role played by the slime filaments continuously extruded from gliding bacteria. This paper solves in full a non-linear mechanical theory that treats as dissipative shocks both the point where the extruded slime filament comes in contact with the substrate, called the filament's foot, and the pore on the bacterium outer surface from where the filament is ejected. We prove that kinematic compatibility for shock propagation requires that the bacterium uniform gliding velocity (relative to the substrate) and the slime ejecting velocity (relative to the bacterium) must be equal, a coincidence that seems to have already been observed.

  8. LACTIC ACID BACTERIA: PROBIOTIC APPLICATIONS

    Directory of Open Access Journals (Sweden)

    NEENA GARG

    2015-10-01

    Full Text Available Lactic acid bacteria (LAB is a heterotrophic Gram-positive bacteria which under goes lactic acid fermentations and leads to production of lactic acid as an end product. LAB includes Lactobacillus, Leuconostoc, Pediococcus, Lactococcus and Streptococcus which are grouped together in the family lactobacillaceae. LAB shows numerous antimicrobial activities due to production of antibacterial and antifungal compounds such as organic acids, bacteriocins, diacetyl, hydrogen peroxide and reutrin. LAB are used as starter culture, consortium members and bioprotective agents in food industry that improve food quality, safety and shelf life. A variety of probiotic LAB species are available including Lactobacillus acidophilus, L. bulgaricus, L. lactis, L. plantarum, L. rhamnosus, L. reuteri, L. fermentum, Bifidobacterium longum, B. breve, B. bifidum, B. esselnsis, B. lactis, B. infantis that are currently recommended for development of functional food products with health-promoting capacities.

  9. Re-engineering bacteria for ethanol production

    Science.gov (United States)

    Yomano, Lorraine P; York, Sean W; Zhou, Shengde; Shanmugam, Keelnatham; Ingram, Lonnie O

    2014-05-06

    The invention provides recombinant bacteria, which comprise a full complement of heterologous ethanol production genes. Expression of the full complement of heterologous ethanol production genes causes the recombinant bacteria to produce ethanol as the primary fermentation product when grown in mineral salts medium, without the addition of complex nutrients. Methods for producing the recombinant bacteria and methods for producing ethanol using the recombinant bacteria are also disclosed.

  10. IDENTIFICATION OF BACTERIA IN LATEX PAINTS

    OpenAIRE

    Rojas, J

    2008-01-01

    The bacteria are prokaryote organisms with a high capacity to colonize many types of habits. This research was developed with the object to identify extremophiles bacteria presents in latex paint. The bacteria were cultivated in culture mediums TSA, Blood Agar, Mc Conkey and finally the biochemical proof API-NF® for bacteria's isolation and identification, respectively. Characterization showed bacterial profile of Pasteurella sp. Hypothesis that could be found extremophiles bac...

  11. Compartmentalization of bacteria in microcapsules.

    Science.gov (United States)

    van Wijk, Judith; Heunis, Tiaan; Harmzen, Elrika; Dicks, Leon M T; Meuldijk, Jan; Klumperman, Bert

    2014-12-18

    Lactobacillus plantarum strain 423 was encapsulated in hollow poly(organosiloxane) microcapsules by templating water-in-oil Pickering emulsion droplets via the interfacial reaction of alkylchlorosilanes. The bacteria were suspended in growth medium or buffer to protect the cells against pH changes during the interfacial reactions with alkylchlorosilanes. The results of this work open up novel avenues for the encapsulation of microbial cells.

  12. Folate Production by Probiotic Bacteria

    OpenAIRE

    Stefano Raimondi; Alberto Amaretti; Maddalena Rossi

    2011-01-01

    Probiotic bacteria, mostly belonging to the genera Lactobacillus and Bifidobacterium, confer a number of health benefits to the host, including vitamin production. With the aim to produce folate-enriched fermented products and/or develop probiotic supplements that accomplish folate biosynthesis in vivo within the colon, bifidobacteria and lactobacilli have been extensively studied for their capability to produce this vitamin. On the basis of physiological studies and genome analysis, wild-typ...

  13. Magnetotactic Bacteria from Extreme Environments

    OpenAIRE

    Lefèvre, Christopher T; Dennis A. Bazylinski

    2013-01-01

    Magnetotactic bacteria (MTB) represent a diverse collection of motile prokaryotes that biomineralize intracellular, membrane-bounded, tens-of-nanometer-sized crystals of a magnetic mineral called magnetosomes. Magnetosome minerals consist of either magnetite (Fe3O4) or greigite (Fe3S4) and cause cells to align along the Earth’s geomagnetic field lines as they swim, a trait called magnetotaxis. MTB are known to mainly inhabit the oxic–anoxic interface (OAI) in water columns or sediments of aqu...

  14. Development of a respiratory sensitization/elicitation protocol of toluene diisocyanate (TDI) in Brown Norway rats to derive an elicitation-based occupational exposure level

    International Nuclear Information System (INIS)

    Highlights: • Toluene diisocyanate (TDI) was unequivocally identified as asthmagens in BN-rats. • The elicitation response on BAL-PMN was threshold-dose dependent. • The elicitation of asthma-like responses follow a concentration × time-relationship. • The human-equivalent dose–response was duplicated in rats. • The derived occupational exposure level (OEL) matches current standards. - Abstract: Toluene diisocyanate (TDI), a known human asthmagen, was investigated in skin-sensitized Brown Norway rats for its concentration × time (C × t)-response relationship on elicitation-based endpoints. The major goal of study was to determine the elicitation inhalation threshold dose in sensitized, re-challenged Brown Norway rats, including the associated variables affecting the dosimetry of inhaled TDI-vapor in rats and as to how these differences can be translated to humans. Attempts were made to duplicate at least some traits of human asthma by using skin-sensitized rats which were subjected to single or multiple inhalation-escalation challenge exposures. Two types of dose-escalation protocols were used to determine the elicitation-threshold C × t; one used a variable C (Cvar) and constant t (tconst), the other a constant C (Cconst) and variable t (tvar). The selection of the ''minimal irritant'' C was based an ancillary pre-studies. Neutrophilic granulocytes (PMNs) in bronchoalveolar lavage fluid (BAL) were considered as the endpoint of choice to integrate the allergic pulmonary inflammation. These were supplemented by physiological measurements characterizing nocturnal asthma-like responses and increased nitric oxide in exhaled breath (eNO). The Cconst × tvar regimen yielded the most conclusive dose–response relationship as long C was high enough to overcome the scrubbing capacity of the upper airways. Based on ancillary pre-studies in naïve rats, the related human-equivalent respiratory tract irritant threshold concentration was

  15. Characterization of Mediterranean Magnetotactic Bacteria

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Magnetotactic bacteria are a diverse group of motile prokaryotes that are ubiquitous in aquatic habitats and cosmopolitan in distribution. In this study, we collected magnetotactic bacteria from the Mediterranean Sea. A remarkable diversity of morphotypes was observed, including muiticellular types that seemed to differ from those previously found in North and South America. Another interesting organism was one with magnetosomes arranged in a six-stranded bundle which occupied one third of the cell width. The magnetosome bundle was evident even under optic microscopy. These cells were connected together and swam as a linear entire unit. Magnetosomes did not always align up to form a straight linear chain. A chain composed of rectangle magnetosomes bent at a position with an oval crystal. High resolution transmission electron microscopy analysis of the crystal at the pivotal position suggested uncompleted formation of the crystal. This is the first report of Mediterranean magnetotactic bacteria, which should be useful for studies of biogeochemical cycling and geohistory of the Mediterranean Sea.

  16. Laser-Based Identification of Pathogenic Bacteria

    Science.gov (United States)

    Rehse, Steven J.

    2009-01-01

    Bacteria are ubiquitous in our world. From our homes, to our work environment, to our own bodies, bacteria are the omnipresent although often unobserved companions to human life. Physicists are typically untroubled professionally by the presence of these bacteria, as their study usually falls safely outside the realm of our typical domain. In the…

  17. Nitrogen-fixing methane-utilizing bacteria

    NARCIS (Netherlands)

    Bont, de J.A.M.

    1976-01-01

    Methane occurs abundantly in nature. In the presence of oxygen this gas may be metabolized by bacteria that are able to use it as carbon and energy source. Several types of bacteria involved in the oxidation of methane have been described in literature. Methane-utilizing bacteria have in common that

  18. Drosophila lifespan enhancement by exogenous bacteria

    OpenAIRE

    Brummel, Ted; Ching, Alisa; Seroude, Laurent; Simon, Anne F.; Benzer, Seymour

    2004-01-01

    We researched the lifespan of Drosophila under axenic conditions compared with customary procedure. The experiments revealed that the presence of bacteria during the first week of adult life can enhance lifespan, despite unchanged food intake. Later in life, the presence of bacteria can reduce lifespan. Certain long-lived mutants react in different ways, indicating an interplay between bacteria and longevity-enhancing genes.

  19. Current strategies for improving food bacteria

    NARCIS (Netherlands)

    Kuipers, O P; Buist, Girbe; Kok, Jan

    2000-01-01

    Novel concepts and methodologies are emerging that hold great promise for the directed improvement of food-related bacteria, specifically lactic acid bacteria. Also, the battle against food spoilage and pathogenic bacteria can now be fought more effectively. Here we describe recent advances in micro

  20. DMPD: Macrophage activation through CCR5- and CXCR4-mediated gp120-elicited signalingpathways. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 12960231 Macrophage activation through CCR5- and CXCR4-mediated gp120-elicited sign...82. Epub 2003 Jul 22. (.png) (.svg) (.html) (.csml) Show Macrophage activation through CCR5- and CXCR4-media...on through CCR5- and CXCR4-mediated gp120-elicited signalingpathways. Authors Lee C, Liu QH, Tomkowicz B, Yi