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  1. THE MAGNETIC SENSITIVITY OF THE Mg ii k LINE TO THE JOINT ACTION OF HANLE, ZEEMAN, AND MAGNETO-OPTICAL EFFECTS

    Energy Technology Data Exchange (ETDEWEB)

    Ballester, E. Alsina; Bueno, J. Trujillo [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain); Belluzzi, L., E-mail: ealsina@iac.es, E-mail: jtb@iac.es, E-mail: belluzzi@irsol.ch [Istituto Ricerche Solari Locarno, CH-6605 Locarno Monti (Switzerland)

    2016-11-10

    We highlight the main results of a radiative transfer investigation on the magnetic sensitivity of the solar Mg ii k resonance line at 2795.5 Å, accounting for the joint action of the Hanle and Zeeman effects as well as partial frequency redistribution phenomena. We confirm that at the line center, the linear polarization signals produced by scattering processes are measurable, and that they are sensitive, via the Hanle effect, to magnetic fields with strengths between 5 and 50 G, approximately. We also show that the Zeeman effect produces conspicuous circular polarization signals, especially for longitudinal fields stronger than 50 G, which can be used to estimate the magnetization of the solar chromosphere via the familiar magnetograph formula. The most novel result is that magneto-optical effects produce, in the wings of the line, a decrease of the Q / I scattering polarization pattern and the appearance of U / I signals (i.e., a rotation of the plane of linear polarization). This sensitivity of the Q / I and U / I wing signals to both weak (∼5 G) and stronger magnetic fields expands the scientific interest of the Mg ii k line for probing the chromosphere in quiet and active regions of the Sun.

  2. THE MAGNETIC SENSITIVITY OF THE Mg ii k LINE TO THE JOINT ACTION OF HANLE, ZEEMAN, AND MAGNETO-OPTICAL EFFECTS

    International Nuclear Information System (INIS)

    Ballester, E. Alsina; Bueno, J. Trujillo; Belluzzi, L.

    2016-01-01

    We highlight the main results of a radiative transfer investigation on the magnetic sensitivity of the solar Mg ii k resonance line at 2795.5 Å, accounting for the joint action of the Hanle and Zeeman effects as well as partial frequency redistribution phenomena. We confirm that at the line center, the linear polarization signals produced by scattering processes are measurable, and that they are sensitive, via the Hanle effect, to magnetic fields with strengths between 5 and 50 G, approximately. We also show that the Zeeman effect produces conspicuous circular polarization signals, especially for longitudinal fields stronger than 50 G, which can be used to estimate the magnetization of the solar chromosphere via the familiar magnetograph formula. The most novel result is that magneto-optical effects produce, in the wings of the line, a decrease of the Q / I scattering polarization pattern and the appearance of U / I signals (i.e., a rotation of the plane of linear polarization). This sensitivity of the Q / I and U / I wing signals to both weak (∼5 G) and stronger magnetic fields expands the scientific interest of the Mg ii k line for probing the chromosphere in quiet and active regions of the Sun.

  3. SOME THEORETICAL MODELS EXPLAINING ADVERTISING EFFECTS

    Directory of Open Access Journals (Sweden)

    Vasilica Magdalena SOMEŞFĂLEAN

    2014-06-01

    Full Text Available Persuade clients is still the main focus of the companies, using a set of methods and techniques designed to influence their behavior, in order to obtain better results (profits over a longer period of time. Since the late nineteenth - early twentieth century, the american E.St.Elmo Lewis, considered a pioneer in advertising and sales, developed the first theory, AIDA model, later used by marketers and advertisers to develop a marketing communications strategy. Later studies have developed other models that are the main subject of this research, which explains how and why persuasive communication works, to understand why some approaches are effective and others are not.

  4. Explaining dysfunctional effects of lexicographical communication

    African Journals Online (AJOL)

    user

    tion in the TLC is the theory of conversational implicature (Grice 1975, etc.). Levinson. (1983: 101-102) summarises Grice's co-operative principle and maxims with regard to the efficient and effective use .... Brown and Yule (1983: 2) claim linguists and linguistic philosophers generally adopt, namely "that the most important ...

  5. Explaining Interaction Effects within and across Levels of Analysis

    DEFF Research Database (Denmark)

    Andersson, Ulf; Cuervo-Cazurra, Alvaro; Nielsen, Bo Bernhard

    2014-01-01

    Many manuscripts submitted to the Journal of International Business Studies propose an interaction effect in their models in an effort to explain the complexity and contingency of relationships across borders. In this article, we provide guidance on how best to explain the interaction effects...

  6. Can selection explain the protective effects of farming on asthma?

    Directory of Open Access Journals (Sweden)

    Wijnand Eduard

    2015-09-01

    No healthy worker selection into farming was observed and changes in asthma prevalence due to early retirement were small. Selection effects are therefore unlikely to explain the protective effects of farming on asthma.

  7. The Effect of Self-Explaining on Robust Learning

    Science.gov (United States)

    Hausmann, Robert G. M.; VanLehn, Kurt

    2010-01-01

    Self-explaining is a domain-independent learning strategy that generally leads to a robust understanding of the domain material. However, there are two potential explanations for its effectiveness. First, self-explanation generates additional "content" that does not exist in the instructional materials. Second, when compared to…

  8. Explaining University Students' Effective Use of E-Learning Platforms

    Science.gov (United States)

    Moreno, Valter; Cavazotte, Flavia; Alves, Isabela

    2017-01-01

    Students' success in e-learning programs depends on how they adopt and embed technology into their learning activities. Drawing on the Technology Acceptance Model, we propose a framework to explain students' intention to use e-learning platforms effectively, that is, their intention to fully exploit system's functionalities in leaning processes,…

  9. Dual interferometry with a tunable point of minimum magnetic sensitivity

    Science.gov (United States)

    Gomez, Eduardo; Hamzeloui, Saeed; Martinez, Daniel; Abediyeh, Vahide; Arias, Nieves; Valenzuela, Victor Manuel

    2016-05-01

    The clock transition is well known for its minimum magnetic sensitivity at B = 0. The hyperfine transition between F = 1, m = -1 and F = 2, m = 1 in 87Rb also shows a point of minimum magnetic sensitivity but it happens at a field of 3.2 Gauss. An interferometer that uses a mixture of the previous two transitions gives a minimum of magnetic sensitivity at a tunable value of the magnetic field between 0 and 3.2 Gauss. The desired magnetic field value can be selected by varying the population in each transition. The relative populations are controlled with a microwave pulse joining states in both interferometers. Support from CONACYT and Fundacion Marcos Moshinsky.

  10. Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

    Directory of Open Access Journals (Sweden)

    Evanthia Mantzouki

    2018-04-01

    Full Text Available Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins. Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a and cytotoxins (e.g., cylindrospermopsin due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.

  11. Can modified gravity from extra dimensions explain dark matter effects?

    International Nuclear Information System (INIS)

    Kar, S.; Bharadwaj, S.; Pal, S.

    2006-01-01

    Observations on galaxy rotation curves and X-ray profiles of galaxy clusters over several decades have shown us that there exists a need for non-luminous (dark) matter. Cosmological observations also point towards the existence of dark components of two kinds - dark matter and dark energy - which, together, seem to be most of what is there the universe. However, for several years, there has been a line of thought which proposes modified gravity as an alternative to dark matter. In this article, we show, how the effective Einstein equations which arise in the context of the currently fashionable warped braneworld models, can explain the effects of dark matter as a manifestation of the consequences of the existence of extra dimensions. Finally, in order to distinguish between the effects of material dark matter and modified gravity, we calculate gravitational lensing in our modified gravity theory and show distinct differences in the deflection angles. If confirmed with observations, our results may shed new light on the existence of extra dimensions and dark matter. (authors)

  12. Can selection explain the protective effects of farming on asthma?

    Directory of Open Access Journals (Sweden)

    Wijnand Eduard

    2015-09-01

    Full Text Available [i][/i]Introduction and objective. Reduced asthma and allergy risks in farmers have been ascribed to microbial exposures. However, selection may also play a role and this was assessed in two Scandinavian farming populations. Materials and methods. Asthma prevalence in 739 Danish farming students was compared to that of 1,105 siblings. 8,482 Norwegian farmers were also compared with 349 early retired farmers. Results. The prevalence of ever-asthma was 5.4% in farming students and 5.2% in siblings (OR 1.1; 95%CI 0.73–1.7. Current asthma in farmers was 3.0% compared to 6.3% in farmers who had retired early (OR 1.8, 95%CI 1.1–2.9. Adjustments for early retirement increased the asthma prevalence by 0.3–0.6%. Farmers who had changed production were more likely to have asthma (OR 9.8, 95% CI 6.0–16. Conclusions. No healthy worker selection into farming was observed and changes in asthma prevalence due to early retirement were small. Selection effects are therefore unlikely to explain the protective effects of farming on asthma.

  13. Magnetically sensitive nanodiamond-doped tellurite glass fibers.

    Science.gov (United States)

    Ruan, Yinlan; Simpson, David A; Jeske, Jan; Ebendorff-Heidepriem, Heike; Lau, Desmond W M; Ji, Hong; Johnson, Brett C; Ohshima, Takeshi; Afshar V, Shahraam; Hollenberg, Lloyd; Greentree, Andrew D; Monro, Tanya M; Gibson, Brant C

    2018-01-19

    Traditional optical fibers are insensitive to magnetic fields, however many applications would benefit from fiber-based magnetometry devices. In this work, we demonstrate a magnetically sensitive optical fiber by doping nanodiamonds containing nitrogen vacancy centers into tellurite glass fibers. The fabrication process provides a robust and isolated sensing platform as the magnetic sensors are fixed in the tellurite glass matrix. Using optically detected magnetic resonance from the doped nanodiamonds, we demonstrate detection of local magnetic fields via side excitation and longitudinal collection. This is a first step towards intrinsically magneto-sensitive fiber devices with future applications in medical magneto-endoscopy and remote mineral exploration sensing.

  14. Explaining the Effects of Communities of Pastoral Care for Students

    Science.gov (United States)

    Murphy, Joseph; Holste, Linda

    2016-01-01

    This article explains how communities of pastoral care work. It presents an empirically forged theory in action. We examined theoretical and empirical work across the targeted area of personalization for students. We also completed what Hallinger (2012) refers to as "exhaustive review" of the field of school improvement writ large. We…

  15. Biodiversity effects on soil processes explained by interspecific functional dissimilarity

    NARCIS (Netherlands)

    Heemsbergen, D.A.; Berg, M.P.; Loreau, M.; Hal, van J.R.; Faber, J.H.; Verhoef, H.A.

    2004-01-01

    The loss of biodiversity can have significant impacts on ecosystem functioning, but the mechanisms involved lack empirical confirmation. Using soil microcosms, we show experimentally that functional dissimilarity among detritivorous species, not species number, drives community compositional effects

  16. Biodiversity effects on soil processes explained by interspecific functional dissimilarity.

    NARCIS (Netherlands)

    Heemsbergen, D.A.; Berg, M.P.; Loreau, M.; van Hal, J.R.; Faber, J.H.; Verhoef, H.A.

    2004-01-01

    The loss of biodiversity can have significant impacts on ecosystem functioning, but the mechanisms involved lack empirical confirmation. Using soil microcosms, we show experimentally that functional dissimilarity among detritivorous species, not species number, drives community compositional effects

  17. Explaining National Border Effects in the Quad Food Trade

    OpenAIRE

    Olper, Alessandro; Raimondi, Valentina

    2006-01-01

    Starting from a theoretically consistent gravity model, this paper first provides estimates of bilateral 'border effects' in food trade among Quad countries (Canada, USA, Japan and EU) at the ISIC 4-digit level. Then, it investigates the underlying reasons of border effect, assessing the role played by policy barriers (tariffs and non-tariff barriers) with respect to barriers unrelated to trade policy, such as information related costs and cultural proximity. In contrast with several previous...

  18. Can monaural temporal masking explain the ongoing precedence effect?

    Science.gov (United States)

    Freyman, Richard L; Morse-Fortier, Charlotte; Griffin, Amanda M; Zurek, Patrick M

    2018-02-01

    The precedence effect for transient sounds has been proposed to be based primarily on monaural processes, manifested by asymmetric temporal masking. This study explored the potential for monaural explanations with longer ("ongoing") sounds exhibiting the precedence effect. Transient stimuli were single lead-lag noise burst pairs; ongoing stimuli were trains of 63 burst pairs. Unlike with transients, monaural masking data for ongoing sounds showed no advantage for the lead, and are inconsistent with asymmetric audibility as an explanation for ongoing precedence. This result, along with supplementary measurements of interaural time discrimination, suggests different explanations for transient and ongoing precedence.

  19. Entrepreneurial Orientation: The Dimensions' Shared Effects on Explaining Firm Performance

    DEFF Research Database (Denmark)

    Lomberg, Carina; Urbig, Diemo; Stockmann, Christoph

    2016-01-01

    We shed new light on the structure of the relationship between entrepreneurial orientation (EO) and firm performance and how this relationship varies across contexts. Using commonality analysis, we decompose the variance in performance—in terms of the effects of innovativeness, proactiveness, and...

  20. Another frame, another game? : Explaining framing effects in economic games

    NARCIS (Netherlands)

    Gerlach, Philipp; Jaeger, B.; Hopfensitz, A.; Lori, E.

    2016-01-01

    Small changes in the framing of games (i.e., the way in which the game situation is described to participants) can have large effects on players' choices. For example, referring to a prisoner's dilemma game as the "Community Game" as opposed to the "Wall Street Game" can double the cooperation rate

  1. Drug-drug interaction may explain failed antibiotic effectiveness - an ...

    African Journals Online (AJOL)

    The in vivo effect of co-administration of the NSAIDs (acetyl salicylic acid (ASA), piroxicam, indomethacin and paracetamol) with ciprofloxacin against Staphylococcus aureus in Swiss mice, rendered neutropenic by pre-treatment with cyclophosphamide, was evaluated using animal model. Using the murine thigh model, ...

  2. How Anxiety and Enthusiasm Help Explain the Bandwagon Effect

    NARCIS (Netherlands)

    Stolwijk, S.B.; Schuck, A.R.T.; de Vreese, C.H.

    2017-01-01

    This study investigates the role of emotions in the (bandwagon) effect of opinion polls on vote choice. It combines a media content analysis of poll reporting (N = 2,772) on an individual basis with a two wave panel survey (N = 1,064) during the 2013 German Bundestag election campaign. Results show

  3. Alignment of Carbon Nanotubes Comprising Magnetically Sensitive Metal Oxides in Nanofluids

    Science.gov (United States)

    Hong, Haiping (Inventor); Peterson, G. P. " Bud" (Inventor)

    2016-01-01

    The present invention is a nanoparticle mixture or suspension or nanofluid comprising nonmagnetically sensitive nanoparticles, magnetically sensitive nanoparticles, and surfactant(s). The present invention also relates to methods of preparing and using the same.

  4. Effects of emotion regulation strategies on music-elicited emotions: An experimental study explaining individual differences

    NARCIS (Netherlands)

    Karreman, A.; Laceulle, O.M.; Hanser, Waldie; Vingerhoets, Ad

    This experimental study examined if emotional experience can be manipulated by applying an emotion regulation strategy during music listening and if individual differences in effects of strategies can be explained by person characteristics. Adults (N = 466) completed questionnaires and rated

  5. Effects of emotion regulation strategies on music elicited emotions : An experimental study explaining individual differences

    NARCIS (Netherlands)

    Karreman, A.; Laceulle, O.M.; Hanser, W.E.; Vingerhoets, A.J.J.M.

    2017-01-01

    This experimental study examined if emotional experience can be manipulated by applying an emotion regulation strategy during music listening and if individual differences in effects of strategies can be explained by person characteristics. Adults (N = 466) completed questionnaires and rated

  6. Why pinning by surface irregularities can explain the peak effect in ...

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 66; Issue 1. Why pinning by surface irregularities can explain the peak effect in transport properties and neutron diffraction results in NbSe2 and Bi-2212 crystals? Charles Simon Alain Pautrat Christophe Goupil Joseph Scola Patrice Mathieu Annie Brûlet Antoine ...

  7. A Hierarchical Bayes Error Correction Model to Explain Dynamic Effects of Price Changes

    NARCIS (Netherlands)

    D. Fok (Dennis); R. Paap (Richard); C. Horváth (Csilla); Ph.H.B.F. Franses (Philip Hans)

    2005-01-01

    textabstractThe authors put forward a sales response model to explain the differences in immediate and dynamic effects of promotional prices and regular prices on sales. The model consists of a vector autoregression rewritten in error-correction format which allows to disentangle the immediate

  8. General Relativity Explains the Shnoll Effect and Makes Possible Forecasting Earthquakes and Weather Cataclysms

    Science.gov (United States)

    Rabounski, Dmitri; Borissova, Larissa

    2014-03-01

    The Shnoll effect is manifested in the fine structure of the noise registered in stable processes, wherein as the magnitude of signal and the average noise remain unchanged. It is periodic fluctuation of the fine structure of the noise according to the cosmic cycles connected with stars, the Sun, and the Moon. The Shnoll effect is explained herein according to General Relativity, as the twin/entangled synchronization states of the observer's reference frame. The states are repeated while the observer travels, in common with the Earth, through the cosmic grid of the geodesic synchronization paths that connect his local reference frame with the reference frames of the other cosmic bodies. These synchronization periods are expected to be existing in the noise of natural processes of any type (physics, biology, social, etc.) and such artificial processes as the random number generation by a computer software. These periods match with the periods of the Shnoll effect. The theory gives not only to explain the Shnoll effect, but also allows forecasting the fluctuations in the stock exchange market, the fluctuations of weather, earthquakes, and other cataclysms.

  9. Mathematical models for explaining the Warburg effect: a review focussed on ATP and biomass production.

    Science.gov (United States)

    Schuster, Stefan; Boley, Daniel; Möller, Philip; Stark, Heiko; Kaleta, Christoph

    2015-12-01

    For producing ATP, tumour cells rely on glycolysis leading to lactate to about the same extent as on respiration. Thus, the ATP synthesis flux from glycolysis is considerably higher than in the corresponding healthy cells. This is known as the Warburg effect (named after German biochemist Otto H. Warburg) and also applies to striated muscle cells, activated lymphocytes, microglia, endothelial cells and several other cell types. For similar phenomena in several yeasts and many bacteria, the terms Crabtree effect and overflow metabolism respectively, are used. The Warburg effect is paradoxical at first sight because the molar ATP yield of glycolysis is much lower than that of respiration. Although a straightforward explanation is that glycolysis allows a higher ATP production rate, the question arises why cells do not re-allocate protein to the high-yield pathway of respiration. Mathematical modelling can help explain this phenomenon. Here, we review several models at various scales proposed in the literature for explaining the Warburg effect. These models support the hypothesis that glycolysis allows for a higher proliferation rate due to increased ATP production and precursor supply rates. © 2015 Authors; published by Portland Press Limited.

  10. The role of internal coupling activities in explaining the effectiveness of open innovation

    DEFF Research Database (Denmark)

    Burcharth, Ana Luiza de Araújo; Knudsen, Mette Præst; Søndergaard, Helle Alsted

    2013-01-01

    This paper investigates the role of internal contingencies in explaining performance implications of open innovation by addressing the questions: does openness drive innovation performance? And if so, what organizational activities impact the effectiveness of both the inbound and the outbound...... approaches to openness? The empirical basis of the study is a survey carried out in 321 Danish SMEs in manufacturing industries. The paper finds limited evidence of the direct effects of inbound and outbound open innovation on performance, as measured in terms of innovative output and profitability. It also...... finds that the effect of openness is mediated by the use of internal coupling activities that give employees latitude, information and skills to work autonomously. A key result is that the benefits of open innovation are fully captured only when firms adopt a number of activities that provide employees...

  11. Testing the Effectiveness of Environmental Variables to Explain European Terrestrial Vertebrate Species Richness across Biogeographical Scales.

    Directory of Open Access Journals (Sweden)

    Maud Mouchet

    Full Text Available We compared the effectiveness of environmental variables, and in particular of land-use indicators, to explain species richness patterns across taxonomic groups and biogeographical scales (i.e. overall pan-Europe and ecoregions within pan-Europe. Using boosted regression trees that handle non-linear relationships, we compared the relative influence (as a measure of effectiveness of environmental variables related to climate, landscape (or habitat heterogeneity, land-use intensity or energy availability to explain European vertebrate species richness (birds, amphibians, and mammals at the continental and ecoregion scales. We found that dominant land cover and actual evapotranspiration that relate to energy availability were the main correlates of vertebrate species richness over Europe. At the ecoregion scale, we identified four distinct groups of ecoregions where species richness was essentially associated to (i seasonality of temperature, (ii actual evapotranspiration and/or mean annual temperature, (iii seasonality of precipitation, actual evapotranspiration and land cover and (iv and an even combination of the environmental variables. This typology of ecoregions remained valid for total vertebrate richness and the three vertebrate groups taken separately. Despite the overwhelming influence of land cover and actual evapotranspiration to explain vertebrate species richness patterns at European scale, the ranking of the main correlates of species richness varied between regions. Interestingly, landscape and land-use indicators did not stand out at the continental scale but their influence greatly increased in southern ecoregions, revealing the long-lasting human footprint on land-use-land-cover changes. Our study provides one of the first multi-scale descriptions of the variability in the ranking of correlates across several taxa.

  12. Changes in materials properties explain the effects of humidity on gecko adhesion.

    Science.gov (United States)

    Puthoff, Jonathan B; Prowse, Michael S; Wilkinson, Matt; Autumn, Kellar

    2010-11-01

    Geckos owe their remarkable stickiness to millions of dry setae on their toes, and the mechanism of adhesion in gecko setae has been the topic of scientific scrutiny for over two centuries. Previously, we demonstrated that van der Waals forces are sufficient for strong adhesion and friction in gecko setae, and that water-based capillary adhesion is not required. However, recent studies demonstrated that adhesion increases with relative humidity (RH) and proposed that surface hydration and capillary water bridge formation is important or even necessary. In this study, we confirmed a significant effect of RH on gecko adhesion, but rejected the capillary adhesion hypothesis. While contact forces of isolated tokay gecko setal arrays increased with humidity, the increase was similar on hydrophobic and hydrophilic surfaces, inconsistent with a capillary mechanism. Contact forces increased with RH even at high shear rates, where capillary bridge formation is too slow to affect adhesion. How then can a humidity-related increase in adhesion and friction be explained? The effect of RH on the mechanical properties of setal β-keratin has escaped consideration until now. We discovered that an increase in RH softens setae and increases viscoelastic damping, which increases adhesion. Changes in setal materials properties, not capillary forces, fully explain humidity-enhanced adhesion, and van der Waals forces remain the only empirically supported mechanism of adhesion in geckos.

  13. The Importance of Stochastic Effects for Explaining Entrainment in the Zebrafish Circadian Clock

    Directory of Open Access Journals (Sweden)

    Raphaela Heussen

    2015-01-01

    Full Text Available The circadian clock plays a pivotal role in modulating physiological processes and has been implicated, either directly or indirectly, in a range of pathological states including cancer. Here we investigate how the circadian clock is entrained by external cues such as light. Working with zebrafish cell lines and combining light pulse experiments with simulation efforts focused on the role of synchronization effects, we find that even very modest doses of light exposure are sufficient to trigger some entrainment, whereby a higher light intensity or duration correlates with strength of the circadian signal. Moreover, we observe in the simulations that stochastic effects may be considered an essential feature of the circadian clock in order to explain the circadian signal decay in prolonged darkness, as well as light initiated resynchronization as a strong component of entrainment.

  14. The observed human sperm mutation frequency cannot explain the achondroplasia paternal age effect

    Science.gov (United States)

    Tiemann-Boege, Irene; Navidi, William; Grewal, Raji; Cohn, Dan; Eskenazi, Brenda; Wyrobek, Andrew J.; Arnheim, Norman

    2002-01-01

    The lifelong spermatogonial stem cell divisions unique to male germ cell production are thought to contribute to a higher mutation frequency in males. The fact that certain de novo human genetic conditions (e.g., achondroplasia) increase in incidence with the age of the father is consistent with this idea. Although it is assumed that the paternal age effect is the result of an increasing frequency of mutant sperm as a man grows older, no direct molecular measurement of the germ-line mutation frequency has been made to confirm this hypothesis. Using sperm DNA from donors of different ages, we determined the frequency of the nucleotide substitution in the fibroblast growth factor receptor 3 (FGFR3) gene that causes achondroplasia. Surprisingly, the magnitude of the increase in mutation frequency with age appears insufficient to explain why older fathers have a greater chance of having a child with this condition. A number of alternatives may explain this discrepancy, including selection for sperm that carry the mutation or an age-dependent increase in premutagenic lesions that remain unrepaired in sperm and are inefficiently detected by the PCR assay. PMID:12397172

  15. Explaining Effects and Side Effects of School Inspections: A Path Analysis

    Science.gov (United States)

    Penninckx, Maarten; Vanhoof, Jan; De Maeyer, Sven; Van Petegem, Peter

    2016-01-01

    There are large differences between schools with regard to how they are affected by a school inspection. This study provides quantitative evidence about the extent to which perceived effects and side effects of an inspection are related to the inspection's judgement on the school, to features of the inspection, and to school features. This study…

  16. Complexity explained

    CERN Document Server

    Erdi, Peter

    2008-01-01

    This book explains why complex systems research is important in understanding the structure, function and dynamics of complex natural and social phenomena. Readers will learn the basic concepts and methods of complex system research.

  17. A path analysis model for explaining unsafe behavior in workplaces: the effect of perceived work pressure.

    Science.gov (United States)

    Ghasemi, Fakhradin; Kalatpour, Omid; Moghimbeigi, Abbas; Mohhamadfam, Iraj

    2018-06-01

    Unsafe behavior is closely related to occupational accidents. Work pressure is one the main factors affecting employees' behavior. The aim of the present study was to provide a path analysis model for explaining how work pressure affects safety behavior. Using a self-administered questionnaire, six variables supposed to affect safety employees' behavior were measured. The path analysis model was constructed based on several hypotheses. The goodness of fit of the model was assessed using both absolute and comparative fit indices. Work pressure was determined not to influence safety behavior directly. However, it negatively influenced other variables. Group attitude and personal attitude toward safety were the main factors mediating the effect of work pressure on safety behavior. Among the variables investigated in the present study, group attitude, personal attitude and work pressure had the strongest effects on safety behavior. Managers should consider that in order to improve employees' safety behavior, work pressure should be reduced to a reasonable level, and concurrently a supportive environment, which ensures a positive group attitude toward safety, should be provided. Replication of the study is recommended.

  18. New evidence for positive selection helps explain the paternal age effect observed in achondroplasia

    Science.gov (United States)

    Shinde, Deepali N.; Elmer, Dominik P.; Calabrese, Peter; Boulanger, Jérôme; Arnheim, Norman; Tiemann-Boege, Irene

    2013-01-01

    There are certain de novo germline mutations associated with genetic disorders whose mutation rates per generation are orders of magnitude higher than the genome average. Moreover, these mutations occur exclusively in the male germ line and older men have a higher probability of having an affected child than younger ones, known as the paternal age effect (PAE). The classic example of a genetic disorder exhibiting a PAE is achondroplasia, caused predominantly by a single-nucleotide substitution (c.1138G>A) in FGFR3. To elucidate what mechanisms might be driving the high frequency of this mutation in the male germline, we examined the spatial distribution of the c.1138G>A substitution in a testis from an 80-year-old unaffected man. Using a technology based on bead-emulsion amplification, we were able to measure mutation frequencies in 192 individual pieces of the dissected testis with a false-positive rate lower than 2.7 × 10−6. We observed that most mutations are clustered in a few pieces with 95% of all mutations occurring in 27% of the total testis. Using computational simulations, we rejected the model proposing an elevated mutation rate per cell division at this nucleotide site. Instead, we determined that the observed mutation distribution fits a germline selection model, where mutant spermatogonial stem cells have a proliferative advantage over unmutated cells. Combined with data on several other PAE mutations, our results support the idea that the PAE, associated with a number of Mendelian disorders, may be explained primarily by a selective mechanism. PMID:23740942

  19. Effect of explaining radiographic information to the patient before third molar surgery

    Science.gov (United States)

    Christensen, J; Matzen, L H; Wenzel, A

    2010-01-01

    Objectives The aim of this study was to compare patient satisfaction with the pre-operative information before and after explaining the radiograph and to compare patient satisfaction with the radiographic information when based on a digital or a conventional image, as well as on extraoral or intraoral images. Methods 263 patients (with 301 mandibular third molars) were given pre-operative information by one of two trained scholar students before removal of the third molar. The course of the surgery and possible post-operative complications and risks were explained to the patient. The patients rated their satisfaction with the information on a 100 mm visual analogue scale (VAS). The radiograph was displayed and the radiographic information was explained to the patient, with emphasis on tooth-specific risk factors. The patients again rated their satisfaction on a VAS. Results There was no significant difference in patient satisfaction score before (mean VAS = 92.5 mm) and after (mean VAS = 91.7 mm) the radiographic information was explained (P = 0.15). No difference in satisfaction was found between patients who were shown either digital or conventional images or between patients who were shown either extraoral or intraoral images (P > 0.5). Conclusions No additional patient satisfaction was obtained by showing and explaining the radiograph to the patient before lower third molar surgery. If the dentist still wishes to show the patient the radiograph, the type of image seems not to be important. PMID:20203280

  20. Brain temporal complexity in explaining the therapeutic and cognitive effects of seizure therapy.

    Science.gov (United States)

    Farzan, Faranak; Atluri, Sravya; Mei, Ye; Moreno, Sylvain; Levinson, Andrea J; Blumberger, Daniel M; Daskalakis, Zafiris J

    2017-04-01

    Over 350 million people worldwide suffer from depression, a third of whom are medication-resistant. Seizure therapy remains the most effective treatment in depression, even when many treatments fail. The utility of seizure therapy is limited due to its cognitive side effects and stigma. The biological targets of seizure therapy remain unknown, hindering design of new treatments with comparable efficacy. Seizures impact the brains temporal dynamicity observed through electroencephalography. This dynamicity reflects richness of information processing across distributed brain networks subserving affective and cognitive processes. We investigated the hypothesis that seizure therapy impacts mood (depressive symptoms) and cognition by modulating brain temporal dynamicity. We obtained resting-state electroencephalography from 34 patients (age = 46.0 ± 14.0, 21 females) receiving two types of seizure treatments-electroconvulsive therapy or magnetic seizure therapy. We used multi-scale entropy to quantify the complexity of the brain's temporal dynamics before and after seizure therapy. We discovered that reduction of complexity in fine timescales underlined successful therapeutic response to both seizure treatments. Greater reduction in complexity of fine timescales in parieto-occipital and central brain regions was significantly linked with greater improvement in depressive symptoms. Greater increase in complexity of coarse timescales was associated with greater decline in cognition including the autobiographical memory. These findings were region and timescale specific. That is, change in complexity in occipital regions (e.g. O2 electrode or right occipital pole) at fine timescales was only associated with change in depressive symptoms, and not change in cognition, and change in complexity in parieto-central regions (e.g. Pz electrode or intra and transparietal sulcus) at coarser timescale was only associated with change in cognition, and not depressive symptoms. Finally

  1. SPSS explained

    CERN Document Server

    Hinton, Perry R; Brownlow, Charlotte

    2014-01-01

    SPSS Explained provides the student with all that they need to undertake statistical analysis using SPSS. It combines a step-by-step approach to each procedure with easy to follow screenshots at each stage of the process. A number of other helpful features are provided: regular advice boxes with tips specific to each test explanations divided into 'essential' and 'advanced' sections to suit readers at different levels frequently asked questions at the end of each chapter. The first edition of this popular book has been fully updated for IBM SPSS version 21 and also includes: chapters that expl

  2. Explaining public unease about nuclear technology and some ways towards effective communication

    International Nuclear Information System (INIS)

    Vlek, Charles

    1998-01-01

    dismantling outdated reactors. The list gives an indication of the process character of a risky undertaking: risks (and benefits) may occur in early, intermediate and late stages of the whole venture. Thus, proper management of (perceived) risks should cover the entire course of action. After a brief analysis of various concepts of 'risk' (with some critical remarks about probabilistic risk analysis), an overview is given of prominent conclusions from psychological research on comparative risk judgment, where nuclear electric power generation and storage of radioactive waste invariably come out as a special items in a multidimensional representation. This has implications for communicating and decision making about risks. Also, a simple heuristic rule may explain many people's acceptance of a risky activity or situation. This rule involves a 'yes'-response to the following three basic questions: (a) Are the benefits large enough? (b) Is the activity's catastrophic potential low enough? (c) Is this course of action sufficiently controllable? 'Risk communication' in fact evolves into the design and selection of proper methods and procedures for exchanging relevant information, structuring the relevant decision problem, and evaluating feasible policy options, in a social arena where multiple stake holders each lay their own claims. Ideally, risk (and benefit) communication should accompany all stages of a social decision malting process concerning a major technological issue. Nuclear technology and the social psychology are two distinct worlds. These two worlds, however, may well work together in multidisciplinary attempts to deal more effectively with the management of nuclear power generation, the dismantling of nuclear reactors, and the acceptable storage of radioactive waste. Perhaps the time has come to start some collaborative research

  3. Explaining union participation: The effects of union commitment and demographic factors

    Directory of Open Access Journals (Sweden)

    D Bolton

    2007-10-01

    Full Text Available This study examined the relationship between trade union commitment and union participation among blue-collar workers in South Africa. Survey questionnaires were completed by 93 participants (response rate = 62 %. Findings are consistent with previous research and showed that after controlling for demographic factors, 43% of the variance in participation can be explained by union commitment. In this study, Black participants displayed significantly higher levels of commitment and participation than their Coloured counterparts did.

  4. Astronomy Explained

    Science.gov (United States)

    North, Gerald

    Every year large numbers of people take up the study of astronomy, mostly at amateur level. There are plenty of elementary books on the market, full of colourful photographs, but lacking in proper explanations of how and why things are as they are. Many people eventually wish to go beyond the 'coffee-table book' stage and study this fascinating subject in greater depth. This book is written for them. In addition, many people sit for public examinations in this subject each year and this book is also intended to be of use to them. All the topics from the GCSE syllabus are covered here, with sample questions at the end of each chapter. Astronomy Explained provides a comprehensive treatment of the subject in more depth than is usually found in elementary works, and will be of interest to both amateur astronomers and students of astronomy.

  5. Explaining growth variation over large spatial scales: Effects of temperature and food on walleye growth

    DEFF Research Database (Denmark)

    Mosgaard, Thomas; Venturelli, Paul; Lester, Nigel P.

    2012-01-01

    Most fishes exhibit strong spatial variation in growth. Because fish growth and production are tightly linked, quantifying and explaining variation in growth can mean the difference between successful management and unforeseen collapse. However, disentangling the factors that are responsible...... freshwater fish species in North America. We then use length at age data from yellow perch (Perca flavescens) to identify the mechanisms behind the remaining variation in the length at age – temperature relationship for walleye. A positive perch – walleye relationship indicates that the mechanism behind...

  6. A Bayesian Model of the Uncanny Valley Effect for Explaining the Effects of Therapeutic Robots in Autism Spectrum Disorder.

    Science.gov (United States)

    Ueyama, Yuki

    2015-01-01

    One of the core features of autism spectrum disorder (ASD) is impaired reciprocal social interaction, especially in processing emotional information. Social robots are used to encourage children with ASD to take the initiative and to interact with the robotic tools to stimulate emotional responses. However, the existing evidence is limited by poor trial designs. The purpose of this study was to provide computational evidence in support of robot-assisted therapy for children with ASD. We thus propose an emotional model of ASD that adapts a Bayesian model of the uncanny valley effect, which holds that a human-looking robot can provoke repulsion and sensations of eeriness. Based on the unique emotional responses of children with ASD to the robots, we postulate that ASD induces a unique emotional response curve, more like a cliff than a valley. Thus, we performed numerical simulations of robot-assisted therapy to evaluate its effects. The results showed that, although a stimulus fell into the uncanny valley in the typical condition, it was effective at avoiding the uncanny cliff in the ASD condition. Consequently, individuals with ASD may find it more comfortable, and may modify their emotional response, if the robots look like deformed humans, even if they appear "creepy" to typical individuals. Therefore, we suggest that our model explains the effects of robot-assisted therapy in children with ASD and that human-looking robots may have potential advantages for improving social interactions in ASD.

  7. Gender and General Strain Theory: A Comparison of Strains, Mediating, and Moderating Effects Explaining Three Types of Delinquency

    Science.gov (United States)

    Moon, Byongook; Morash, Merry

    2017-01-01

    The present study of 659 Korean adolescents tests General Strain Theory's (GST) utility in explaining gender differences in delinquency causation. It models the effects of key strains, negative emotions, and a composite measure of several conditioning factors separately for boys and girls and for delinquency. Consistent with the theory, males and…

  8. WAP explained

    International Nuclear Information System (INIS)

    Kaiser, M.J.; Pulsipher, A.G.

    2004-01-01

    The Weatherization Assistance Program (WAP) is a federal block grant program administered by all 50 states and the District of Columbia through community action agencies, state energy offices, local government, and other nonprofit organizations to provide weatherization services to eligible households. The WAP was established in 1976 to increase the energy efficiency, reduce the energy expenditures, and improve the health and safety of low-income households, especially those households that are particularly vulnerable such as families with children, persons with disabilities, and the elderly. The manner in which WAP funds have been allocated to states, however, has been a contentious issue since the inception of the program. Southern states have argued that too much of the federal funding goes to cold-climate and rural states. Northern states disagree. In 1990, Congress amended the Energy Conservation and Production Act and required the Department of Energy to develop a new funding formula. The Department of Energy currently uses a three-factor formula developed in 1995 in conjunction with a two-factor formula developed in 1977 and a hold-harmless provision to allocate WAP funding. The purpose of this paper is to explain the WAP allocation mechanism and the assumptions associated with the 1977 and the 1995 funding formula. The factors that compose each funding formula are critically assessed and various implementation issues are reviewed, including the selection of the trigger point and program capacity levels. It is not possible to define the need for weatherization assistance objectively and in a unique manner, and this ambiguity is the main reason why the WAP allocation mechanism is expected to remain a lively topic of debate and contention

  9. Singled out as the effect to be explained: implications for collective self-esteem.

    Science.gov (United States)

    Bruckmüller, Susanne

    2013-02-01

    The description and explanation of intergroup differences tend to be framed in terms of how nonnormative (untypical and/or stigmatized) groups differ from normative groups rather than vice versa. Three experiments examined how this affects group members' collective self-esteem. Single participants felt worse about being single when they read (Study 1) or wrote (Study 2) about how singles differ from coupled people than when they read or wrote about how coupled people differ from singles-although they mentioned more positive aspects of being single under the former comparative framing. In Study 3, left-handed participants indicated lower private collective self-esteem after writing about how left-handers differ from right-handers than after writing about how right-handers differ from left-handers. Thus, regardless of the specific characteristics that the comparison focused on, being marked as different and having to explain one's group identity negatively affected members of nonnormative, but not members of normative groups.

  10. How Can We Design Low Back Pain Intervention Studies to Better Explain the Effects of Treatment?

    NARCIS (Netherlands)

    Mansell, G.; Hill, J.C.; Kamper, S.J.; Kent, P.; Main, C.; van der Windt, D.A.

    2014-01-01

    The majority of trials investigating the effectiveness of primary care interventions for back pain have shown small or at best, moderate effects of treatment 36 , 37 and the fi eld is looking for better ways to improve outcomes for patients with back pain. Mediation analysis aims to provide better

  11. Different mechanisms to explain the reversed effects of mental health on work characteristics

    NARCIS (Netherlands)

    Lange, A.H. de; Taris, T.W.; Kompier, M.A.J.; Houtman, I.L.D.; Bongers, P.M.

    2005-01-01

    Objectives: The number of longitudinal studies reporting evidence for reversed effects of strain on work is growing, but evidence regarding the mechanisms underlying such effects is scarce. In this study, earlier longitudinal findings were reviewed, and the following four mechanisms for reversed

  12. Explaining the Segmentation Effect in Learning from Animations: The Role of Pausing and Temporal Cueing

    Science.gov (United States)

    Spanjers, Ingrid A. E.; van Gog, Tamara; Wouters, Pieter; van Merrienboer, Jeroen J. G.

    2012-01-01

    Segmentation of animations, that is presenting them in pieces rather than as a continuous stream of information, has been shown to have a beneficial effect on cognitive load and learning for novices. Two different explanations of this segmentation effect have been proposed. Firstly, pauses are usually inserted between the segments, which may give…

  13. Explaining the effects of targeted online advertising on children's cognitive, affective, and behavioral brand responses

    NARCIS (Netherlands)

    van Reijmersdal, E.; Rozendaal, E.; Smink, N.; van Noort, G.; Buijzen, M.

    2013-01-01

    Increasingly, information from children's profile pages on social network sites is used to target online advertising. This practice has raised concerns in society and academia, however, effects of profile targeting on children remained unstudied. Therefore, this study focused on children's

  14. Special health care needs explains the effect of extremely low birth weight on math but not language achievement.

    Science.gov (United States)

    Litt, Jonathan S; Minich, Nori; Taylor, H Gerry; Hack, Maureen

    2017-12-01

    Extremely low birth weight (ELBW; <1kg) adolescents are at risk for special health care needs (SHCN) and poor math achievement compared to normal birth weight (NBW) peers. SHCN are associated with poor academic achievement among NBW children. We hypothesize that SHCN explain the effect of ELBW on math achievement. We compared age 14 Woodcock-Johnson Calculation standard scores between 181 ELBW infants and 115 NBW controls. Persistent SHCN included: 1) prescription medication or equipment use, 2) subspecialty or therapeutic service use, or 3) hospitalization. We used nonlinear marginal effects models to decompose the total effect of ELBW on math into the following 4 components: the effect of ELBW controlling for SHCN, the effect of SHCN controlling for ELBW, effect modification by SHCN, and mediated interaction where SHCN is both causal mediator and effect modifier. Models were adjusted for sociodemographic factors. ELBW adolescents had lower mean math scores than NBW peers (81.3 vs. 96.4). SHCN were more common among ELBW adolescents (54.1% vs. 27%). The total effect of ELBW on math scores was -15.7 points (95% CI -21.0, -10.5). The effect of birth weight alone was -7.6 points (95% CI -13.7, -1.4); the effect of SHCN alone was negligible. SHCN interaction and mediated interaction effects each accounted for 25% of the total effect. Birth weight alone explains only half of the effect of ELBW on math achievement. We found evidence of effect modification and mediation by SHCN. Understanding these explanatory pathways may lead to targeted interventions for improved outcomes. Copyright © 2017. Published by Elsevier B.V.

  15. Cognitive Abilities Explain Wording Effects in the Rosenberg Self-Esteem Scale.

    Science.gov (United States)

    Gnambs, Timo; Schroeders, Ulrich

    2017-12-01

    There is consensus that the 10 items of the Rosenberg Self-Esteem Scale (RSES) reflect wording effects resulting from positively and negatively keyed items. The present study examined the effects of cognitive abilities on the factor structure of the RSES with a novel, nonparametric latent variable technique called local structural equation models. In a nationally representative German large-scale assessment including 12,437 students competing measurement models for the RSES were compared: a bifactor model with a common factor and a specific factor for all negatively worded items had an optimal fit. Local structural equation models showed that the unidimensionality of the scale increased with higher levels of reading competence and reasoning, while the proportion of variance attributed to the negatively keyed items declined. Wording effects on the factor structure of the RSES seem to represent a response style artifact associated with cognitive abilities.

  16. Why pinning by surface irregularities can explain the peak effect in ...

    Indian Academy of Sciences (India)

    Low resistance electrical contacts were made by bonding gold wires with silver epoxy. The DC transport measurements were performed using a standard four probe [11]. 88 ... this state is not due to the kind of stimulation used. Concerning the metastable. V (I) curves, the peak effect in the critical current, the coexistence of ...

  17. Picture or Text First? Explaining Sequence Effects When Learning with Pictures and Text

    Science.gov (United States)

    Eitel, Alexander; Scheiter, Katharina

    2015-01-01

    The present article reviews 42 studies investigating the role of sequencing of text and pictures for learning outcomes. Whereas several of the reviewed studies revealed better learning outcomes from presenting the picture before the text rather than after it, other studies demonstrated the opposite effect. Against the backdrop of theories on…

  18. Explaining the Influence of Workarounds on the Effective Use of a Supply Chain Management System

    NARCIS (Netherlands)

    Li, Yizhou; Haake, Phillip; Mueller, Benjamin; Maedche, Alexander

    2017-01-01

    The stage of post-adoption of an enterprise system implementation has been in the focus of recent information systems research. However, a thorough understanding of how users effectively use an enterprise system to complete their tasks is still missing. Prior research has implied that adaptive use

  19. Education, religiosity and moral attitudes: Explaining cross-national effect differences

    NARCIS (Netherlands)

    Scheepers, P.L.H.; Grotenhuis, H.F. te; Slik, F.W.P. van der

    2002-01-01

    The aim of the present study is to answer three research questions on moral attitudes (i.e., attitudes concerning abortion, premarital and extramarital relations, and homosexual relations) Which parental and individual characteristics affect moral attitudes? Do the effects of parental and individual

  20. The Impact of Type of Examples on Originality: Explaining Fixation and Stimulation Effects

    Science.gov (United States)

    Agogué, Marine; Kazakçi, Akin; Hatchuel, Armand; Le Masson, Pascal; Weil, Benoit; Poirel, Nicolas; Cassotti, Mathieu

    2014-01-01

    There are obstacles to creativity: one of them is called fixation effect, the fact that some knowledge about existing or obvious solutions is spontaneously activated and constrains the generation of new solutions. Converging evidence in cognitive psychology has indicated that the ability to generate original ideas can be limited by recently…

  1. Principal Time Management Skills: Explaining Patterns in Principals' Time Use, Job Stress, and Perceived Effectiveness

    Science.gov (United States)

    Grissom, Jason A.; Loeb, Susanna; Mitani, Hajime

    2015-01-01

    Purpose: Time demands faced by school principals make principals' work increasingly difficult. Research outside education suggests that effective time management skills may help principals meet job demands, reduce job stress, and improve their performance. The purpose of this paper is to investigate these hypotheses. Design/methodology/approach:…

  2. Explaining the Effects of Narrative in an Entertainment Television Program: Overcoming Resistance to Persuasion

    Science.gov (United States)

    Moyer-Guse, Emily; Nabi, Robin L.

    2010-01-01

    Research has examined the ability of entertainment-education (E-E) programs to influence behavior across a variety of health and social issues. However, less is known about the underlying mechanisms that account for these effects. In keeping with the extended elaboration likelihood model (E-ELM) and the entertainment overcoming resistance model…

  3. Explaining the convector effect in canopy turbulence by means of large-eddy simulation

    Science.gov (United States)

    Banerjee, Tirtha; De Roo, Frederik; Mauder, Matthias

    2017-06-01

    Semi-arid forests are found to sustain a massive sensible heat flux in spite of having a low surface to air temperature difference by lowering the aerodynamic resistance to heat transfer (rH) - a property called the canopy convector effect (CCE). In this work large-eddy simulations are used to demonstrate that the CCE appears more generally in canopy turbulence. It is indeed a generic feature of canopy turbulence: rH of a canopy is found to reduce with increasing unstable stratification, which effectively increases the aerodynamic roughness for the same physical roughness of the canopy. This relation offers a sufficient condition to construct a general description of the CCE. In addition, we review existing parameterizations for rH from the evapotranspiration literature and test to what extent they are able to capture the CCE, thereby exploring the possibility of an improved parameterization.

  4. Molecular mechanisms explaining the possible effects of phenolic compounds on reducing the risk of cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Maria Aubets-Fusté

    2013-09-01

    Full Text Available The objective of the present review is to evaluate the possible association between phenolic compounds and cardiovascular disease, proposing that their regular consumption in Western diets could be beneficial for protecting patients against cardiovascular disease. An extensive research of scientific literature was performed in the following electronic specialized databases (PubMed central (PMC-NBCI, Elsevier Journal, Scielo Spain, Scirus, Science Direct, Web of Science, including studies in animals, cells, and humans, to establish the effect of polyphenols in the prevention and development of cardiovascular disease was conducted. The in vitro, animal and human studies show the potential ability of polyphenols to act against cardiovascular disease as a result of their antioxidant effect and vasodilatation and their capacity to improve lipid profile while reducing the concentration of low-density lipoproteins. Polyphenols consumption in Western diets could be beneficial for protecting patients against cardiovascular disease.

  5. Effectiveness of Cooperative Learning Instructional Tools With Predict-Observe-Explain Strategy on the Topic of Cuboid and Cube Volume

    Science.gov (United States)

    Nurhuda; Lukito, A.; Masriyah

    2018-01-01

    This study aims to develop instructional tools and implement it to see the effectiveness. The method used in this research referred to Designing Effective Instruction. Experimental research with two-group pretest-posttest design method was conducted. The instructional tools have been developed is cooperative learning model with predict-observe-explain strategy on the topic of cuboid and cube volume which consist of lesson plans, POE tasks, and Tests. Instructional tools were of good quality by criteria of validity, practicality, and effectiveness. These instructional tools was very effective for teaching the volume of cuboid and cube. Cooperative instructional tool with predict-observe-explain (POE) strategy was good of quality because the teacher was easy to implement the steps of learning, students easy to understand the material and students’ learning outcomes completed classically. Learning by using this instructional tool was effective because learning activities were appropriate and students were very active. Students’ learning outcomes were completed classically and better than conventional learning. This study produced a good instructional tool and effectively used in learning. Therefore, these instructional tools can be used as an alternative to teach volume of cuboid and cube topics.

  6. Does parents' economic, cultural, and social capital explain the social class effect on educational attainment in the Scandinavian mobility regime?

    DEFF Research Database (Denmark)

    Holm, Anders; Jæger, Mads Meier

    2007-01-01

    This paper analyzes how much of the effect of social class on children’s choice of secondary education in Denmark can be decomposed into the influence of parental economic, cultural, and social capital. Following mobility regime theory, we propose that in the Scandinavian mobility regime to which...... for the statistical analysis. Our results are, first, that controlling for the three types of capital we explain a considerable part of the social class effect on educational attainment, and, second, that cultural and social capital are the key predictors of educational attainment....

  7. Explaining ADAGIO: a critical review of the biological basis for the clinical effects of rasagiline.

    Science.gov (United States)

    Jenner, Peter; Langston, J William

    2011-11-01

    The ADAGIO study demonstrated a symptomatic benefit for rasagiline in early Parkinson's disease (PD) and suggested a disease-modifying effect. Evidence indicates that mitochondrial dysfunction plays a role in the pathogenesis of PD and that this may be the site of effect for rasagiline. In this systematic review, evidence for the role of mitochondria in the pathogenesis of PD are reviewed in light of other proposed mechanisms of neuronal degeneration and the actions of rasagiline and its component parts, namely propargylamine and the metabolite, aminoindan. Evidence for the role of mitochondria in the pathogenesis and treatment of PD are reviewed in light of other proposed mechanisms of neuronal degeneration and clinical actions of rasagiline. Monoamine oxidase B (MAO-B) located in the outer mitochondrial membrane controls dopamine metabolism in early PD, and this is the likely location for the symptomatic action of rasagiline. Accumulating evidence indicates that mitochondrial impairment contributes to dopaminergic neuronal loss in PD, either directly or through other mechanisms such as oxidative stress or protein misfolding. Further rasagiline affects numerous mitochondrial mechanisms that prevent apoptotic cell death including prevention of opening of the mitochondrial transition pore, decreased release of cytochrome C, alterations in pro-antiapoptotic genes and proteins, and the nuclear translocation of glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Thus, the functional neuroprotective actions of rasagiline may not be dependent on MAO-B inhibition, but rather may involve actions of the propargylamine moiety and the aminoindan metabolite. An accumulating body of literature indicates a mitochondrial site of action for rasagiline and highlights the neuroprotective action of the drug, providing strong biological plausibility for disease-modifying effects of the drug such as those observed in ADAGIO. Copyright © 2011 Movement Disorder Society.

  8. Explaining the Rise in Danish Vocational Education System Dropouts: The Effect of a Youth Unemployment Program

    DEFF Research Database (Denmark)

    Munk, Martin D.; Park, Do-Yeun

    This project focuses on the impact of Denmark’s Youth Unemployment Program(YUP) enacted in late 1990s on the rise in VET dropout rates. The Youth Unemployment Program targeted unemployed, low-educated youth to strengthen the employment possibilities and to motivate for them to undertake...... an education. If the Youth Unemployment Program incentivized less capable/ambitious students to enter vocational education, it would increase the dropout rates via selection. This project investigates whether the program had an effect on the population characteristics of incoming VET students and the resulting...

  9. Can a linguistic serial founder effect originating in Africa explain the worldwide phonemic cline?

    Science.gov (United States)

    Fort, Joaquim; Pérez-Losada, Joaquim

    2016-04-01

    It has been proposed that a serial founder effect could have caused the present observed pattern of global phonemic diversity. Here we present a model that simulates the human range expansion out of Africa and the subsequent spatial linguistic dynamics until today. It does not assume copying errors, Darwinian competition, reduced contrastive possibilities or any other specific linguistic mechanism. We show that the decrease of linguistic diversity with distance (from the presumed origin of the expansion) arises under three assumptions, previously introduced by other authors: (i) an accumulation rate for phonemes; (ii) small phonemic inventories for the languages spoken before the out-of-Africa dispersal; (iii) an increase in the phonemic accumulation rate with the number of speakers per unit area. Numerical simulations show that the predictions of the model agree with the observed decrease of linguistic diversity with increasing distance from the most likely origin of the out-of-Africa dispersal. Thus, the proposal that a serial founder effect could have caused the present observed pattern of global phonemic diversity is viable, if three strong assumptions are satisfied. © 2016 The Authors.

  10. Benveniste’s Experiments Explained by a Non-Conventional Experimenter Effect

    Directory of Open Access Journals (Sweden)

    Francis Beauvais

    2018-03-01

    Full Text Available Background: Benveniste’s biology experiments suggested the existence of molecular-like effects without molecules (“memory of water”. In this article, it is proposed that these disputed experiments could have been the consequence of a previously unnoticed and non-conventional experimenter effect. Methods: A probabilistic modelling is built in order to describe an elementary laboratory experiment. A biological system is modelled with two possible states (“resting” and “activated” and exposed to two experimental conditions labelled “control” and “test”, but both are biologically inactive. The modelling takes into account not only the biological system, but also the experimenters. In addition, an outsider standpoint is adopted to describe the experimental situation. Results: A classical approach suggests that, after experiment completion, the “control” and “test” labels of biologically-inactive conditions should both be associated with the “resting” state (i.e., no significant relationship between labels and system states. However, if the fluctuations of the biological system are also considered, a quantum-like relationship emerges and connects labels and system states (analogous to a biological “effect” without molecules. Conclusions: No hypotheses about water properties or other exotic explanations are needed to describe Benveniste’s experiments, including their unusual features. This modelling could be extended to other experimental situations in biology, medicine, and psychology.

  11. The rhizosphere priming effect explained by microscale interactions among enzyme producing microbes

    Science.gov (United States)

    Kaiser, Christina; Dieckmann, Ulf; Franklin, Oskar

    2017-04-01

    Addition of small amounts of labile carbon (C), for example by root exudations, have been found to accelerate soil organic matter decomposition ('Priming Effect'). Possible explanations that have been suggested so far are that this C increases microbial turnover or - by increasing nitrogen (N) limitation of microbes - triggers increased mining of microbes for nutrients. Individual-based modeling of microbes at the microscale offer a new and alternative explanation for the emergence of the priming effect: Enzyme producing microbes benefit from proximity to other enzyme producing microbes since this increases their return of investment for each enzyme produced. The benefit grows the more microbes are close to each other, such that growth of a patch of microbes becomes a self-enhancing process. Our results show that there is a 'tipping point' - a critical size of such a patch, or number of spatially related microbes, which is necessary to start this process. In a model setting where soil microbes are C limited and thus only grow slowly, the addition of a small amount of labile C in a certain area is sufficient to trigger the emergence of such a growing microbial patch which consequently increases long-term decomposition rates of soil organic matter far beyond the initial labile C input in the model.

  12. A Twin Protection Effect? Explaining Twin Survival Advantages with a Two-Process Mortality Model.

    Directory of Open Access Journals (Sweden)

    David J Sharrow

    Full Text Available Twin studies that focus on the correlation in age-at-death between twin pairs have yielded important insights into the heritability and role of genetic factors in determining lifespan, but less attention is paid to the biological and social role of zygosity itself in determining survival across the entire life course. Using data from the Danish Twin Registry and the Human Mortality Database, we show that monozygotic twins have greater cumulative survival proportions at nearly every age compared to dizygotic twins and the Danish general population. We examine this survival advantage by fitting these data with a two-process mortality model that partitions survivorship patterns into extrinsic and intrinsic mortality processes roughly corresponding to acute, environmental and chronic, biological origins. We find intrinsic processes confer a survival advantage at older ages for males, while at younger ages, all monozygotic twins show a health protection effect against extrinsic death akin to a marriage protection effect. While existing research suggests an increasingly important role for genetic factors at very advanced ages, we conclude that the social closeness of monozygotic twins is a plausible driver of the survival advantage at ages <65.

  13. A Twin Protection Effect? Explaining Twin Survival Advantages with a Two-Process Mortality Model.

    Science.gov (United States)

    Sharrow, David J; Anderson, James J

    2016-01-01

    Twin studies that focus on the correlation in age-at-death between twin pairs have yielded important insights into the heritability and role of genetic factors in determining lifespan, but less attention is paid to the biological and social role of zygosity itself in determining survival across the entire life course. Using data from the Danish Twin Registry and the Human Mortality Database, we show that monozygotic twins have greater cumulative survival proportions at nearly every age compared to dizygotic twins and the Danish general population. We examine this survival advantage by fitting these data with a two-process mortality model that partitions survivorship patterns into extrinsic and intrinsic mortality processes roughly corresponding to acute, environmental and chronic, biological origins. We find intrinsic processes confer a survival advantage at older ages for males, while at younger ages, all monozygotic twins show a health protection effect against extrinsic death akin to a marriage protection effect. While existing research suggests an increasingly important role for genetic factors at very advanced ages, we conclude that the social closeness of monozygotic twins is a plausible driver of the survival advantage at ages <65.

  14. Hypothesis to Explain the Size Effect Observed in APO-BMI Compression Tests

    Energy Technology Data Exchange (ETDEWEB)

    Schembri, Philip Edward [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Siranosian, Antranik Antonio [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kingston, Lance Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-01-07

    In 2013 compression tests were performed on cylindrical specimens of carbon-microballoon-APOBMI syntactic foam machined to different lengths (0.25, 0.5, and 2.8 inches1) (Kingston, 2013). In 2014 similar tests were performed on glass-microballoon-APO-BMI of different lengths (~0.15”, ~0.32”, and ~0.57”). In all these tests it was observed that, when strains were calculated from the platen displacement (corrected for machine compliance), the apparent Young’s modulus of the material decreased with specimen size, as shown in Table 1. The reason for this size effect was speculated to be a layer of damage on or near the top and bottom machined surfaces of the specimens (Kingston, Schembri, & Siranosian, 2014). This report examines that hypothesis in further detail.

  15. Explaining the contract terms of energy performance contracting in China: The importance of effective financing

    International Nuclear Information System (INIS)

    Li, Yan; Qiu, Yueming; Wang, Yi David

    2014-01-01

    Energy service company (“ESCO”) uses Energy Performance Contracting (“EPC”) to provide energy-saving services to its clients. Under an EPC, both ESCO and the client invest in the energy efficiency measures, according to a negotiated share of investment. Within the length of the contract, the ESCO and its client divide up the saved energy bill according to a negotiated share. Once the contract expires, the client claims all of the saved energy bills if the energy efficiency measures still last. Different EPC projects have different contract terms, including total investment, share of investment and length of contract. These contract terms directly determine the resulted energy savings. Thus it is essential and important to look at how these contract terms are formed and what are the major influencing factors. This paper first builds a theoretical bargain model between ESCO and its client to find out the structural relationship among these contract terms. Then, using the information of about 140 EPC contracts in China in 2010 and 2011, the paper empirically estimates the impacts of various factors on the contract terms and the resulted energy savings. We find that cost of capitals for ESCOs and the clients, especially for ESCOs, is a major factor influencing contract terms and the resulted energy savings. Thus providing effective financing is critical for the development of EPC in China. - Highlights: • We build a theoretical bargain model between an ESCO and its client. • We empirically quantify the impacts of various factors on EPC contract terms. • Cost of capital is a key factor determining EPC contract terms. • Providing effective financing, especially for ESCOs is important

  16. Chaos and the quantum: how nonlinear effects can explain certain quantum paradoxes

    Science.gov (United States)

    McHarris, Wm C.

    2011-07-01

    In recent years we have suggested that many of the so-called paradoxes resulting from the Copenhagen interpretation of quantum mechanics could well have more logical parallels based in nonlinear dynamics and chaos theory. Perhaps quantum mechanics might not be strictly linear as has been commonly postulated, and indeed, during the past year experimentalists have discovered signatures of chaos in a definitely quantum system. As an illustration of what can go wrong when quantum effects are forced into a linear interpretation, I examine Bell-type inequalities. In conventional derivations of such inequalities, classical systems are found to impose upper limits on the statistical correlations between, say, the properties of a pair of separated but entangled particles, whereas quantum systems allow greater correlations. Numerous experiments have upheld the quantum predictions (greater statistical correlations than allowed classically), which has led to inferences such as the instantaneous transmission of information between effectively infinitely separated particles — Einstein's "spooky action-at-a-distance," incompatible with relativity. I argue that there is nothing wrong with the quantum mechanical side of such derivations (the usual point of attack by those attempting to debunk Bell-type arguments), but implicit in the derivations on the classical side is the assumption of independent, uncorrelated particles. As a result, one is comparing uncorrelated probabilities versus conditional probabilities rather than comparing classical versus quantum mechanics, making moot the experimental inferences. Further, nonlinear classical systems are known to exhibit correlations that can easily be as great as and overlap with quantum correlations — so-called nonextensive thermodynamics with its nonadditive entropy has verified this with numerous examples. Perhaps quantum mechanics does contain fundamental nonlinear elements. Nonlinear dynamics and chaos theory could well

  17. Fungal composition on leaves explains pollutant-mediated indirect effects on amphipod feeding.

    Science.gov (United States)

    Bundschuh, Mirco; Zubrod, Jochen P; Kosol, Sujitra; Maltby, Lorraine; Stang, Christoph; Duester, Lars; Schulz, Ralf

    2011-07-01

    The energy stored in coarse particulate organic matter, e.g. leaf litter, is released to aquatic ecosystems by breakdown processes involving microorganisms and leaf shredding invertebrates. The palatability of leaves and thus the feeding of shredders on leaf material are highly influenced by microorganisms. However, implications in the colonization of leaves by microorganisms (=conditioning) caused by chemical stressors are rarely studied. Our laboratory experiments, therefore, investigated for the first time effects of a fungicide on the conditioning process of leaf material by means of food-choice experiments using Gammarus fossarum (Crustacea: Amphipoda). Additionally, microbial analyses were conducted to facilitate the mechanistic understanding of the observed behavior. Gammarids significantly preferred control leaf discs over those conditioned in presence of the fungicide tebuconazole at concentrations of 50 and 500 μg/L. Besides the decrease of fungal biomass with increasing fungicide concentration, also the leaf associated fungal community composition showed that species preferred by gammarids, such as Alatospora acumunata, Clavariopsis aquatica, or Flagellospora curvula, were more frequent in the control. Tetracladium marchalianum, however, which is rejected by gammarids, was abundant in all treatments suggesting an increasing importance of this species for the lower leaf palatability--as other more palatable fungal species were almost absent--in the fungicide treatments. Hence, the food-choice behavior of G. fossarum seems to be a suitable indicator for alterations in leaf associated microbial communities, especially fungal species composition, caused by chemical stressors. Finally, this or similar test systems may be a reasonable supplement to the environmental risk assessment of chemicals in order to achieve its protection goals, as on the one hand, indirect effects may occur far below concentrations known to affect gammarids directly, and on the other

  18. Chaos and the quantum: how nonlinear effects can explain certain quantum paradoxes

    International Nuclear Information System (INIS)

    McHarris, Wm C

    2011-01-01

    In recent years we have suggested that many of the so-called paradoxes resulting from the Copenhagen interpretation of quantum mechanics could well have more logical parallels based in nonlinear dynamics and chaos theory. Perhaps quantum mechanics might not be strictly linear as has been commonly postulated, and indeed, during the past year experimentalists have discovered signatures of chaos in a definitely quantum system. As an illustration of what can go wrong when quantum effects are forced into a linear interpretation, I examine Bell-type inequalities. In conventional derivations of such inequalities, classical systems are found to impose upper limits on the statistical correlations between, say, the properties of a pair of separated but entangled particles, whereas quantum systems allow greater correlations. Numerous experiments have upheld the quantum predictions (greater statistical correlations than allowed classically), which has led to inferences such as the instantaneous transmission of information between effectively infinitely separated particles - Einstein's 'spooky action-at-a-distance', incompatible with relativity. I argue that there is nothing wrong with the quantum mechanical side of such derivations (the usual point of attack by those attempting to debunk Bell-type arguments), but implicit in the derivations on the classical side is the assumption of independent, uncorrelated particles. As a result, one is comparing uncorrelated probabilities versus conditional probabilities rather than comparing classical versus quantum mechanics, making moot the experimental inferences. Further, nonlinear classical systems are known to exhibit correlations that can easily be as great as and overlap with quantum correlations - so-called nonextensive thermodynamics with its nonadditive entropy has verified this with numerous examples. Perhaps quantum mechanics does contain fundamental nonlinear elements. Nonlinear dynamics and chaos theory could well provide a

  19. Reporting explained variance

    Science.gov (United States)

    Good, Ron; Fletcher, Harold J.

    The importance of reporting explained variance (sometimes referred to as magnitude of effects) in ANOVA designs is discussed in this paper. Explained variance is an estimate of the strength of the relationship between treatment (or other factors such as sex, grade level, etc.) and dependent variables of interest to the researcher(s). Three methods that can be used to obtain estimates of explained variance in ANOVA designs are described and applied to 16 studies that were reported in recent volumes of this journal. The results show that, while in most studies the treatment accounts for a relatively small proportion of the variance in dependent variable scores., in., some studies the magnitude of the treatment effect is respectable. The authors recommend that researchers in science education report explained variance in addition to the commonly reported tests of significance, since the latter are inadequate as the sole basis for making decisions about the practical importance of factors of interest to science education researchers.

  20. Ectomycorrhizal host specificity in a changing world: can legacy effects explain anomalous current associations?

    Science.gov (United States)

    Lofgren, Lotus; Nguyen, Nhu H; Kennedy, Peter G

    2018-02-07

    Despite the importance of ectomycorrhizal (ECM) fungi in forest ecosystems, knowledge about the ecological and co-evolutionary mechanisms underlying ECM host associations remains limited. Using a widely distributed group of ECM fungi known to form tight associations with trees in the family Pinaceae, we characterized host specificity among three unique Suillus-host species pairs using a combination of field root tip sampling and experimental bioassays. We demonstrate that the ECM fungus S. subaureus can successfully colonize Quercus hosts in both field and glasshouse settings, making this species unique in an otherwise Pinaceae-specific clade. Importantly, however, we found that the colonization of Quercus by S. subaureus required co-planting with a Pinaceae host. While our experimental results indicate that gymnosperms are required for the establishment of new S. subaureus colonies, Pineaceae hosts are locally absent at both our field sites. Given the historical presence of Pineaceae hosts before human alteration, it appears the current S. subaureus-Quercus associations represent carryover from past host presence. Collectively, our results suggest that patterns of ECM specificity should be viewed not only in light of current forest community composition, but also as a legacy effect of host community change over time. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

  1. Explaining the Effect of Parent-Child Coresidence on Marriage Formation: The Case of Japan.

    Science.gov (United States)

    Yu, Wei-Hsin; Kuo, Janet Chen-Lan

    2016-10-01

    Many single adult children in countries around the world live with their parents. Such coresidence has been thought to delay the transition to first marriage, although the exact reasons for the delay have not been sufficiently examined. Using panel data from Japan, we investigate whether changes in never-married adults' residential status lead to alterations in their marital aspirations, courtship behaviors, romantic opportunities, and perceived obstacles to marrying. Our estimation of fixed-effects models helps address potential bias caused by single individuals' selection into living in the parental home. The analysis indicates that living with parents is associated with a lower probability of forming romantic relationships, thereby decelerating the transition to first marriage. The never-married, however, do not desire marriage less, put less effort into finding romantic partners, or have fewer opportunities to meet potential partners when coresiding with parents. Overall, the findings suggest that living in the parental home increases never-married men's contentment with their immediate social environment, whereas it decreases women's psychological readiness to transition into adult roles, making both men and women less eager to settle into a romantic relationship.

  2. Explaining the decline in Mexico-U.S. Migration: the effect of the Great Recession.

    Science.gov (United States)

    Villarreal, Andrés

    2014-12-01

    The rate of Mexico-U.S. migration has declined precipitously in recent years. From 25 migrants per thousand in 2005, the annual international migration rate for Mexican men dropped to 7 per thousand by 2012. If sustained, this low migration rate is likely to have a profound effect on the ethnic and national-origin composition of the U.S. population. This study examines the origins of the migration decline using a nationally representative panel survey of Mexican households. The results support an explanation that attributes a large part of the decline to lower labor demand for Mexican immigrants in the United States. Decreases in labor demand in industrial sectors that employ a large percentage of Mexican-born workers, such as construction, are found to be strongly associated with lower rates of migration for Mexican men. Second, changes in migrant selectivity are also consistent with an economic explanation for the decline in international migration. The largest declines in migration occurred precisely among the demographic groups most affected by the Great Recession: namely, economically active young men with low education. Results from the statistical analysis also show that the reduction in labor demand in key sectors of the U.S. economy resulted in a more positive educational selectivity of young migrants.

  3. Snake co-occurrence patterns are best explained by habitat and hypothesized effects of interspecific interactions.

    Science.gov (United States)

    Steen, David A; McClure, Christopher J W; Brock, Jean C; Craig Rudolph, D; Pierce, Josh B; Lee, James R; Jeffrey Humphries, W; Gregory, Beau B; Sutton, William B; Smith, Lora L; Baxley, Danna L; Stevenson, Dirk J; Guyer, Craig

    2014-01-01

    Snakes often occur in species-rich assemblages, and sympatry is thought to be facilitated primarily by low diet overlap, not interspecific interactions. We selected, a priori, three species pairs consisting of species that are morphologically and taxonomically similar and may therefore be likely to engage in interspecific, consumptive competition. We then examined a large-scale database of snake detection/nondetection data and used occupancy modelling to determine whether these species occur together more or less frequently than expected by chance while accounting for variation in detection probability among species and incorporating important habitat categories in the models. For some snakes, we obtained evidence that the probabilities that habitat patches are used are influenced by the presence of potentially competing congeneric species. Specifically, timber rattlesnakes (Crotalus horridus) were less likely than expected by chance to use areas that also contained eastern diamond-backed rattlesnakes (Crotalus adamanteus) when the proportion of evergreen forest was relatively high. Otherwise, they occurred together more often than expected by chance. Complex relationships were revealed between habitat use, detection probabilities and occupancy probabilities of North American racers (Coluber constrictor) and coachwhips (Coluber flagellum) that indicated the probability of competitive exclusion increased with increasing area of grassland habitat, although there was some model uncertainty. Cornsnakes (Pantherophis guttatus or Pantherophis slowinskii) and ratsnakes (Pantherophis alleghaniensis, Pantherophis spiloides, or Pantherophis obsoletus) exhibited differences in habitat selection, but we obtained no evidence that patterns of use for this species pair were influenced by current interspecific interactions. Overall, our results are consistent with the hypothesis that competitive interactions influence snake assemblage composition; the strength of these effects was

  4. New Mechanisms to Explain the Effects of Added Lactose Fines on the Dispersion Performance of Adhesive Mixtures for Inhalation

    Science.gov (United States)

    Grasmeijer, Floris; Lexmond, Anne J.; van den Noort, Maarten; Hagedoorn, Paul; Hickey, Anthony J.; Frijlink, Henderik W.; de Boer, Anne H.

    2014-01-01

    Fine excipient particles or ‘fines’ have been shown to improve the dispersion performance of carrier-based formulations for dry powder inhalation. Mechanistic formulation studies have focussed mainly on explaining this positive effect. Previous studies have shown that higher drug contents may cause a decrease in dispersion performance, and there is no reason why this should not be true for fines with a similar shape, size and cohesiveness as drug particles. Therefore, the effects on drug detachment of ‘fine lactose fines’ (FLF, X50 = 1.95 µm) with a similar size and shape as micronised budesonide were studied and compared to those of ‘coarse lactose fines’ (CLF, X50 = 3.94 µm). Furthermore, interactions with the inhalation flow rate, the drug content and the mixing order were taken into account. The observed effects of FLF are comparable to drug content effects in that the detached drug fraction was decreased at low drug content and low flow rates but increased at higher flow rates. At high drug content the effects of added FLF were negligible. In contrast, CLF resulted in higher detached drug fractions at all flow rates and drug contents. The results from this study suggest that the effects of fines may be explained by two new mechanisms in addition to those previously proposed. Firstly, fines below a certain size may increase the effectiveness of press-on forces or cause the formation of strongly coherent fine particle networks on the carrier surface containing the drug particles. Secondly, when coarse enough, fines may prevent the formation of, or disrupt such fine particle networks, possibly through a lowering of their tensile strength. It is recommended that future mechanistic studies are based on the recognition that added fines may have any effect on dispersion performance, which is determined by the formulation and dispersion conditions. PMID:24489969

  5. Alignment of carbon nanotubes comprising magnetically sensitive metal oxides in heat transfer nanofluids

    International Nuclear Information System (INIS)

    Hong, Haiping; Luan, Xinning; Horton, Mark; Li, Chen; Peterson, G.P.

    2011-01-01

    Highlights: → High speed microscopy was utilized to allow real time visualization of the movement of nanoparticles including SWNT and Fe 2 O 3 . → This electrostatic force induced alignment could maintain nanotube perfect conjugate structures which result in excellent thermal, electrical, and mechanical properties. → The alignment of the carbon nanotubes in nanosuspensions may offer new opportunities for the development of nanofluids. → These nanosuspensions also could be used in films, polymer composites, transparent electrodes, electromagnetic interference shielding, new sensors, etc. - Abstract: High speed microscopy was utilized to allow real time visualization of the movement of single walled carbon nanotubes (SWNT) with magnetically sensitive nanoparticles (Fe 2 O 3 ) and a chemical surfactant (NaDSSB) in water. Initially, entangled SWNT, Fe 2 O 3 and NaDSSB mixtures were randomly dispersed in the fluid. Upon extended exposure to the magnetic field, the mixture slowly vibrated, the nanoparticles straightened and aligned with respect to the magnetic field. The aligned nanoparticle chains appeared to be continuous and unbroken, forming a combination of aligned particles and clusters. Because of the semi-continuous nature of these nanosuspensions and the inherent viscosity of the fluid, some minutes are required for the mixtures to respond to the applied magnetic field and align. Time dependent thermal conductivity experiments indicate that the alignment process dominates the thermal conductivity enhancement as opposed to micro convection. Scanning Electron Microscopy (SEM) images also show that the SWNT and Fe 2 O 3 particles are well aligned under the influence of the magnetic field. Verification of the assumption that electrostatic attraction between nanotube/surfactant and metal oxides makes aggregation happen was obtained, by changing the nature of the charge of the surfactant from a negative charge (NaSDDB) to a positive charge (CTAB). Compared

  6. Alignment of carbon nanotubes comprising magnetically sensitive metal oxides in heat transfer nanofluids

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Haiping, E-mail: Haiping.Hong@sdsmt.edu [Department of Material and Metallurgical Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701 (United States); Luan, Xinning; Horton, Mark [Department of Material and Metallurgical Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701 (United States); Li, Chen [Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208 (United States); Peterson, G.P. [Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States)

    2011-10-20

    Highlights: {yields} High speed microscopy was utilized to allow real time visualization of the movement of nanoparticles including SWNT and Fe{sub 2}O{sub 3}. {yields} This electrostatic force induced alignment could maintain nanotube perfect conjugate structures which result in excellent thermal, electrical, and mechanical properties. {yields} The alignment of the carbon nanotubes in nanosuspensions may offer new opportunities for the development of nanofluids. {yields} These nanosuspensions also could be used in films, polymer composites, transparent electrodes, electromagnetic interference shielding, new sensors, etc. - Abstract: High speed microscopy was utilized to allow real time visualization of the movement of single walled carbon nanotubes (SWNT) with magnetically sensitive nanoparticles (Fe{sub 2}O{sub 3}) and a chemical surfactant (NaDSSB) in water. Initially, entangled SWNT, Fe{sub 2}O{sub 3} and NaDSSB mixtures were randomly dispersed in the fluid. Upon extended exposure to the magnetic field, the mixture slowly vibrated, the nanoparticles straightened and aligned with respect to the magnetic field. The aligned nanoparticle chains appeared to be continuous and unbroken, forming a combination of aligned particles and clusters. Because of the semi-continuous nature of these nanosuspensions and the inherent viscosity of the fluid, some minutes are required for the mixtures to respond to the applied magnetic field and align. Time dependent thermal conductivity experiments indicate that the alignment process dominates the thermal conductivity enhancement as opposed to micro convection. Scanning Electron Microscopy (SEM) images also show that the SWNT and Fe{sub 2}O{sub 3} particles are well aligned under the influence of the magnetic field. Verification of the assumption that electrostatic attraction between nanotube/surfactant and metal oxides makes aggregation happen was obtained, by changing the nature of the charge of the surfactant from a negative

  7. Explaining competitive reaction effects

    NARCIS (Netherlands)

    Leeflang, P.S.H.; Wittink, D.R.

    Changes in promotional expenditure decisions for a brand, as in other marketing decisions, should be based on the expected impact on purchase and consumption behavior as well as on the likely reactions by competitors. Purchase behavior may be predicted from estimated demand functions. Competitive

  8. The Kok effect in Vicia faba cannot be explained solely by changes in chloroplastic CO2concentration.

    Science.gov (United States)

    Buckley, Thomas N; Vice, Heather; Adams, Mark A

    2017-12-01

    The Kok effect - an abrupt decline in quantum yield (QY) of net CO 2 assimilation at low photosynthetic photon flux density (PPFD) - is widely used to estimate respiration in the light (R), which assumes the effect is caused by light suppression of R. A recent report suggested much of the Kok effect can be explained by declining chloroplastic CO 2 concentration (c c ) at low PPFD. Several predictions arise from the hypothesis that the Kok effect is caused by declining c c , and we tested these predictions in Vicia faba. We measured CO 2 exchange at low PPFD, in 2% and 21% oxygen, in developing and mature leaves, which differed greatly in R in darkness. Our results contradicted each of the predictions based on the c c effect: QY exceeded the theoretical maximum value for photosynthetic CO 2 uptake; QY was larger in 21% than 2% oxygen; and the change in QY at the Kok effect breakpoint was unaffected by oxygen. Our results strongly suggest the Kok effect arises largely from a progressive decline in R with PPFD that includes both oxygen-sensitive and -insensitive components. We suggest an improved Kok method that accounts for high c c at low PPFD. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  9. On sponsoring and CSR involvement. Two theories explaining their effects on a company’s attractiveness for candidates

    Directory of Open Access Journals (Sweden)

    Jacek Wozniak

    2016-04-01

    Full Text Available The use of e-recruitment for hiring personnel is constantly expanding. However, the scientific understanding of factors affecting company employer brand during e-recruitment, is still poor. Research into corporate social responsibilities (CSR shows that information about the company’s involvement in these areas makes its image more positive, including its image as an employer. CSR is an umbrella concept, which includes activities similar to traditional sponsoring of sports and cultural events. Two theories explaining the impact of information on attractiveness of the employer’s brand in the e-recruitment process are presented. The aim of the text is to check which of them – cultural fit or signaling theory – more adequately explains the changes in how a candidate perceives a company’s attractiveness, when given information about its’ sports and cultural sponsoring and environment-related activities. The effect of both positive and negative information concerning a company’s activities on its employer image in the e-recruitment situation is analyzed. Data from an questionnaire filled in by 80 young full-time workers shows that positive information about a company’s CSR and sponsoring activities affects candidates according to the cultural fit model, while negative – according to the signaling theory model. The consequences for theory and managerial practice are described.

  10. Acute and Chronic Effects of Dietary Lactose in Adult Rats Are not Explained by Residual Intestinal Lactase Activity

    Directory of Open Access Journals (Sweden)

    Bert J. M. van de Heijning

    2015-07-01

    Full Text Available Neonatal rats have a high intestinal lactase activity, which declines around weaning. Yet, the effects of lactose-containing products are often studied in adult animals. This report is on the residual, post-weaning lactase activity and on the short- and long-term effects of lactose exposure in adult rats. Acutely, the postprandial plasma response to increasing doses of lactose was studied, and chronically, the effects of a 30% lactose diet fed from postnatal (PN Day 15 onwards were evaluated. Intestinal lactase activity, as assessed both in vivo and in vitro, was compared between both test methods and diet groups (lactose vs. control. A 50%–75% decreased digestive capability towards lactose was observed from weaning into adulthood. Instillation of lactose in adult rats showed disproportionally low increases in plasma glucose levels and did not elicit an insulin response. However, gavages comprising maltodextrin gave rise to significant plasma glucose and insulin responses, indicative of a bias of the adult GI tract to digest glucose polymers. Despite the residual intestinal lactase activity shown, a 30% lactose diet was poorly digested by adult rats: the lactose diet rendered the animals less heavy and virtually devoid of body fat, whereas their cecum tripled in size, suggesting an increased bacterial fermentation. The observed acute and chronic effects of lactose exposure in adult rats cannot be explained by the residual intestinal lactase activity assessed.

  11. Acute and Chronic Effects of Dietary Lactose in Adult Rats Are not Explained by Residual Intestinal Lactase Activity.

    Science.gov (United States)

    van de Heijning, Bert J M; Kegler, Diane; Schipper, Lidewij; Voogd, Eline; Oosting, Annemarie; van der Beek, Eline M

    2015-07-08

    Neonatal rats have a high intestinal lactase activity, which declines around weaning. Yet, the effects of lactose-containing products are often studied in adult animals. This report is on the residual, post-weaning lactase activity and on the short- and long-term effects of lactose exposure in adult rats. Acutely, the postprandial plasma response to increasing doses of lactose was studied, and chronically, the effects of a 30% lactose diet fed from postnatal (PN) Day 15 onwards were evaluated. Intestinal lactase activity, as assessed both in vivo and in vitro, was compared between both test methods and diet groups (lactose vs. control). A 50%-75% decreased digestive capability towards lactose was observed from weaning into adulthood. Instillation of lactose in adult rats showed disproportionally low increases in plasma glucose levels and did not elicit an insulin response. However, gavages comprising maltodextrin gave rise to significant plasma glucose and insulin responses, indicative of a bias of the adult GI tract to digest glucose polymers. Despite the residual intestinal lactase activity shown, a 30% lactose diet was poorly digested by adult rats: the lactose diet rendered the animals less heavy and virtually devoid of body fat, whereas their cecum tripled in size, suggesting an increased bacterial fermentation. The observed acute and chronic effects of lactose exposure in adult rats cannot be explained by the residual intestinal lactase activity assessed.

  12. Differing chemical compositions of three teas may explain their different effects on acute blood pressure in spontaneously hypertensive rats.

    Science.gov (United States)

    Li, Shan-Bing; Li, Yi-Fang; Mao, Zhong-Fu; Hu, Hui-Hua; Ouyang, Shu-Hua; Wu, Yan-Ping; Tsoi, Bun; Gong, Pin; Kurihara, Hiroshi; He, Rong-Rong

    2015-04-01

    Heavy tea consumption is suggested to be unsuitable for hypertensive people. However, the bioactive substances in different varieties of tea leaves are very different. This study compares the effects of three Chinese teas - C. sinensis, C. ptilophylla and C. assamica var. kucha - on blood pressure (BP) and heart rate in spontaneously hypertensive rats (SHRs). Intragastric administration of C. sinensis extract led to an acute increase in systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate in SHRs. However, C. ptilophylla and C. assamica var. kucha exerted no obvious influences on SBP, DBP or heart rate. Similar to the extract of C. sinensis, intragastric administration of caffeine also led to an acute increase in BP and heart rate in SHRs. In contrast, theobromine and theacrine - purine alkaloids predominantly contained in C. ptilophylla and C. assamica var. kucha, respectively - had no pressor effects. The effect of caffeine on BP was related to the regulation of plasma epinephrine and norepinephrine levels in SHRs. The different effects of C. sinensis, C. ptilophylla and C. assamica var. kucha on BP might be explained, at least partially, by the differences in the varieties and contents of purine alkaloids. © 2014 Society of Chemical Industry.

  13. A Feedback Model of Attention Explains the Diverse Effects of Attention on Neural Firing Rates and Receptive Field Structure.

    Directory of Open Access Journals (Sweden)

    Thomas Miconi

    2016-02-01

    Full Text Available Visual attention has many effects on neural responses, producing complex changes in firing rates, as well as modifying the structure and size of receptive fields, both in topological and feature space. Several existing models of attention suggest that these effects arise from selective modulation of neural inputs. However, anatomical and physiological observations suggest that attentional modulation targets higher levels of the visual system (such as V4 or MT rather than input areas (such as V1. Here we propose a simple mechanism that explains how a top-down attentional modulation, falling on higher visual areas, can produce the observed effects of attention on neural responses. Our model requires only the existence of modulatory feedback connections between areas, and short-range lateral inhibition within each area. Feedback connections redistribute the top-down modulation to lower areas, which in turn alters the inputs of other higher-area cells, including those that did not receive the initial modulation. This produces firing rate modulations and receptive field shifts. Simultaneously, short-range lateral inhibition between neighboring cells produce competitive effects that are automatically scaled to receptive field size in any given area. Our model reproduces the observed attentional effects on response rates (response gain, input gain, biased competition automatically scaled to receptive field size and receptive field structure (shifts and resizing of receptive fields both spatially and in complex feature space, without modifying model parameters. Our model also makes the novel prediction that attentional effects on response curves should shift from response gain to contrast gain as the spatial focus of attention drifts away from the studied cell.

  14. A Feedback Model of Attention Explains the Diverse Effects of Attention on Neural Firing Rates and Receptive Field Structure.

    Science.gov (United States)

    Miconi, Thomas; VanRullen, Rufin

    2016-02-01

    Visual attention has many effects on neural responses, producing complex changes in firing rates, as well as modifying the structure and size of receptive fields, both in topological and feature space. Several existing models of attention suggest that these effects arise from selective modulation of neural inputs. However, anatomical and physiological observations suggest that attentional modulation targets higher levels of the visual system (such as V4 or MT) rather than input areas (such as V1). Here we propose a simple mechanism that explains how a top-down attentional modulation, falling on higher visual areas, can produce the observed effects of attention on neural responses. Our model requires only the existence of modulatory feedback connections between areas, and short-range lateral inhibition within each area. Feedback connections redistribute the top-down modulation to lower areas, which in turn alters the inputs of other higher-area cells, including those that did not receive the initial modulation. This produces firing rate modulations and receptive field shifts. Simultaneously, short-range lateral inhibition between neighboring cells produce competitive effects that are automatically scaled to receptive field size in any given area. Our model reproduces the observed attentional effects on response rates (response gain, input gain, biased competition automatically scaled to receptive field size) and receptive field structure (shifts and resizing of receptive fields both spatially and in complex feature space), without modifying model parameters. Our model also makes the novel prediction that attentional effects on response curves should shift from response gain to contrast gain as the spatial focus of attention drifts away from the studied cell.

  15. Transient competitive complexation in biological kinetic isotope fractionation explains nonsteady isotopic effects: Theory and application to denitrification in soils

    Science.gov (United States)

    Maggi, Federico; Riley, William J.

    2009-12-01

    The theoretical formulation of biological kinetic isotope fractionation often assumes first-order or Michaelis-Menten kinetics, the latter solved under the quasi-steady state assumption. Both formulations lead to a constant isotope fractionation factor, therefore they may return incorrect estimations of isotopic effects and misleading interpretations of isotopic signatures when fractionation is not a steady process. We have analyzed the isotopic signature of denitrification in biogeochemical soil systems by Menyailo and Hungate (2006) in which high and variable 15N-N2O enrichment during N2O production and inverse isotope fractionation during N2O consumption could not be explained with first-order kinetics and the Rayleigh equation, or with Michaelis-Menten kinetics. When Michaelis-Menten kinetics were coupled to Monod kinetics to describe biomass and enzyme dynamics, and the quasi-steady state assumption was relaxed, transient Michaelis-Menten-Monod kinetics accurately reproduced the observed concentrations, and variable and inverse isotope fractionations. These results imply a substantial revision in modeling isotopic effects, suggesting that steady state kinetics such as first-order, Rayleigh, and classic Michaelis-Menten kinetics should be superseded by transient kinetics in conjunction with biomass and enzyme dynamics.

  16. Susceptibility to the audience effect explains performance gap between children with and without autism in a theory of mind task.

    Science.gov (United States)

    Chevallier, Coralie; Parish-Morris, Julia; Tonge, Natasha; Le, Lori; Miller, Judith; Schultz, Robert T

    2014-06-01

    Diminished social motivation constitutes one of the core impairments of autism spectrum disorder (ASD) and is thought to have a strong impact on the way individuals with autism respond to the presence of others. In this study, we hypothesized that experimental contexts involving direct interaction with an experimenter might elicit different reactions in children with ASD and thus act as a potential confound in the interpretation of group differences during social cognitive tests. Following classic work in social psychology on the audience effect-wherein individuals act differently when they are being watched in a more or less conscious attempt to enhance their reputation in the eyes of others-we reasoned that social contexts are indeed likely to produce an increase in performance in typically developing (TD) individuals but that children with ASD would be less susceptible to such audience effects. More specifically, we were interested in testing the idea that susceptibility to the audience effect might explain part of the performance gap between children with autism (ASDs) and children without autism in theory of mind (ToM) tasks, which are typically administered by a human experimenter. We tested this hypothesis by comparing performance on a ToM task administered in a social versus a nonsocial setting. We found that ASDs and controls performed similarly when the task was administered using a nonsocial medium. However, control participants outperformed ASDs when an experimenter administered the task. Thus, TD controls demonstrated a relative improvement in performance when in the presence of an experimenter that children with ASD did not. The implications of this diminished audience effect in ASD are discussed. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  17. EPIGENETIC EFFECT OF TESTOSTERONE IN THE BEHAVIOR OF C. ELEGANS. A CLUE TO EXPLAIN ANDROGEN-DEPENDENT AUTISTIC TRAITS?

    Directory of Open Access Journals (Sweden)

    M Mar eGámez-del-Estal

    2014-03-01

    Full Text Available Current research indicates that the causes of autism spectrum disorders (ASDs are multifactorial and include both genetic and environmental factors. To date, several works have associated ASDs with mutations in genes that encode proteins involved in neuronal synapses; however other factors and the way they can interact with the development of the nervous system remain largely unknown. Some studies have established a direct relationship between risk for ASDs and the exposure of the fetus to high testosterone levels during the prenatal stage. In this work, in order to explain possible mechanisms by which this androgenic hormone may interact with the nervous system, C. elegans was used as an experimental model. We observed that testosterone was able to alter the behavioral pattern of the worm, including the gentle touch response and the pharyngeal pumping rate. This impairment of the behavior was abolished using specific RNAi against genes orthologous to the human androgen receptor gene. The effect of testosterone was eliminated in the nhr-69 (ok1926 deficient mutant, a putative ortholog of human AR gene, suggesting that this gene encodes a receptor able to interact with the hormone. On the other hand the testosterone effect remained in the gentle touch response during four generations in the absence of the hormone, indicating that some epigenetic mechanisms could be involved. Sodium butyrate, a histone deacetylase inhibitor, was able to abolish the effect of testosterone. In addition, the lasting effect of testosterone was eliminated after the dauer stage. These results suggest that testosterone may impair the nervous system function generating transgenerational epigenetic marks in the genome. This work may provide new paradigms for understanding biological mechanisms involved in ASDs.

  18. Comparative proteomic analysis of rice after seed ground simulated radiation and spaceflight explains the radiation effects of space environment

    Science.gov (United States)

    Wang, Wei; Shi, Jinming; Liang, Shujian; Lei, Huang; Shenyi, Zhang; Sun, Yeqing

    , ground simulation method could be utilized to simu-late the space radiation biological effects and such a comparative proteomic work might explain both energy and dose effects of space radiation environment.

  19. Bird species diversity in the Atlantic Forest of Brazil is not explained by the Mid-domain Effect

    Directory of Open Access Journals (Sweden)

    Vagner Cavarzere

    2012-08-01

    Full Text Available The Atlantic Forest is an excellent case study for the elevational diversity of birds, and some inventories along elevational gradients have been carried out in Brazil. Since none of these studies explain the patterns of species richness with elevation, we herein review all Brazilian studies on bird elevational diversity, and test a geometric constraint null model that predicts a unimodal species-altitude curve, the Mid-domain Effect (MDE. We searched for bird inventories in the literature and also analysed our own survey data using limited-radius point counts along an 800 m elevational gradient in the state of São Paulo, Brazil. We found 10 investigations of elevational diversity of Atlantic Forest birds and identified five different elevational patterns: monotonic decreasing diversity, constant at low elevations, constant at low elevations but increasing towards the middle, and two undescribed patterns for Atlantic Forest birds, trough-shaped and increasing diversity. The average MDE fit was low (r² = 0.31 and none of the MDE predictions were robust across all gradients. Those studies with good MDE model fits had obvious sampling bias. Although it has been proposed that the MDE may be positively associated with the elevational diversity of birds, it does not fit the Brazilian Atlantic Forest bird elevational diversity.

  20. Integration of anatomical and external response mappings explains crossing effects in tactile localization: A probabilistic modeling approach.

    Science.gov (United States)

    Badde, Stephanie; Heed, Tobias; Röder, Brigitte

    2016-04-01

    To act upon a tactile stimulus its original skin-based, anatomical spatial code has to be transformed into an external, posture-dependent reference frame, a process known as tactile remapping. When the limbs are crossed, anatomical and external location codes are in conflict, leading to a decline in tactile localization accuracy. It is unknown whether this impairment originates from the integration of the resulting external localization response with the original, anatomical one or from a failure of tactile remapping in crossed postures. We fitted probabilistic models based on these diverging accounts to the data from three tactile localization experiments. Hand crossing disturbed tactile left-right location choices in all experiments. Furthermore, the size of these crossing effects was modulated by stimulus configuration and task instructions. The best model accounted for these results by integration of the external response mapping with the original, anatomical one, while applying identical integration weights for uncrossed and crossed postures. Thus, the model explained the data without assuming failures of remapping. Moreover, performance differences across tasks were accounted for by non-individual parameter adjustments, indicating that individual participants' task adaptation results from one common functional mechanism. These results suggest that remapping is an automatic and accurate process, and that the observed localization impairments in touch result from a cognitively controlled integration process that combines anatomically and externally coded responses.

  1. Opposing effects of smoking in ulcerative colitis and Crohn's disease may be explained by differential effects on dendritic cells.

    Science.gov (United States)

    Ueno, Aito; Jijon, Humberto; Traves, Suzanne; Chan, Ronald; Ford, Kim; Beck, Paul L; Iacucci, Marietta; Fort Gasia, Miriam; Barkema, Herman W; Panaccione, Remo; Kaplan, Gilaad G; Proud, David; Ghosh, Subrata

    2014-05-01

    The mechanisms underlying the differential effects of cigarette smoking in patients with Crohn's disease (CD) and ulcerative colitis (UC) remain unknown. Smoking has been demonstrated to be protective in UC, whereas in CD it has been shown to be associated with a more severe course, more frequent relapses, and postoperative recurrence. Dendritic cells (DC) play a critical role in T-cell activation and differentiation. Thus, we examined the effects of in vitro exposure to cigarette smoke extract (CSE) on phenotype/function of DC obtained from patients with UC and CD. Sixty-eight subjects were recruited including 30 patients with CD, 19 patients with UC, and 19 healthy controls. Peripheral blood monocytes were differentiated to DC in presence of IL-4 and granulocyte-macrophage colony-stimulating factor. The influence of CSE on Mo-DC subsets, cytokine expression, and ability to drive T cell proliferation and polarization were examined. CSE affected DC phenotypes including increases in class-2 major histocompatibility complex and costimulatory molecules and decreases in CXCL10 and CCL3 levels in UC compared with CD samples. Furthermore, CSE also altered DC function resulting in increasing T cell proliferation and Th1 polarization in CD, whereas it increased Foxp3+ T cells and decreased the Th1 subset in UC samples. CSE modulates DC phenotype and function in patients with UC leading to increased prevalence of Foxp3+ CD4 T cells, whereas in patients with CD it skews toward Th1 subsets. Differential DC responses to CSE between CD and UC may contribute to the differential effects associated with cigarette smoking status.

  2. Changes in the dynamics of the cardiac troponin C molecule explain the effects of Ca2+-sensitizing mutations.

    Science.gov (United States)

    Stevens, Charles M; Rayani, Kaveh; Singh, Gurpreet; Lotfalisalmasi, Bairam; Tieleman, D Peter; Tibbits, Glen F

    2017-07-14

    Cardiac troponin C (cTnC) is the regulatory protein that initiates cardiac contraction in response to Ca 2+ TnC binding Ca 2+ initiates a cascade of protein-protein interactions that begins with the opening of the N-terminal domain of cTnC, followed by cTnC binding the troponin I switch peptide (TnI SW ). We have evaluated, through isothermal titration calorimetry and molecular-dynamics simulation, the effect of several clinically relevant mutations (A8V, L29Q, A31S, L48Q, Q50R, and C84Y) on the Ca 2+ affinity, structural dynamics, and calculated interaction strengths between cTnC and each of Ca 2+ and TnI SW Surprisingly the Ca 2+ affinity measured by isothermal titration calorimetry was only significantly affected by half of these mutations including L48Q, which had a 10-fold higher affinity than WT, and the Q50R and C84Y mutants, each of which had affinities 3-fold higher than wild type. This suggests that Ca 2+ affinity of the N-terminal domain of cTnC in isolation is insufficient to explain the pathogenicity of these mutations. Molecular-dynamics simulation was used to evaluate the effects of these mutations on Ca 2+ binding, structural dynamics, and TnI interaction independently. Many of the mutations had a pronounced effect on the balance between the open and closed conformations of the TnC molecule, which provides an indirect mechanism for their pathogenic properties. Our data demonstrate that the structural dynamics of the cTnC molecule are key in determining myofilament Ca 2+ sensitivity. Our data further suggest that modulation of the structural dynamics is the underlying molecular mechanism for many disease mutations that are far from the regulatory Ca 2+ -binding site of cTnC. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Calories or protein? The effect of dietary restriction on lifespan in rodents is explained by calories alone.

    Science.gov (United States)

    Speakman, J R; Mitchell, S E; Mazidi, M

    2016-12-15

    Almost exactly 100years ago Osborne and colleagues demonstrated that restricting the food intake of a small number of female rats extended their lifespan. In the 1930s experiments on the impact of diet on lifespan were extended by Slonaker, and subsequently McCay. Slonaker concluded that there was a strong impact of protein intake on lifespan, while McCay concluded that calories are the main factor causing differences in lifespan when animals are restricted (Calorie restriction or CR). Hence from the very beginning the question of whether food restriction acts on lifespan via reduced calorie intake or reduced protein intake was disputed. Subsequent work supported the idea that calories were the dominant factor. More recently, however, this role has again been questioned, particularly in studies of insects. Here we review the data regarding previous studies of protein and calorie restriction in rodents. We show that increasing CR (with simultaneous protein restriction: PR) increases lifespan, and that CR with no PR generates an identical effect. None of the residual variation in the impact of CR (with PR) on lifespan could be traced to variation in macronutrient content of the diet. Other studies show that low protein content in the diet does increase median lifespan, but the effect is smaller than the CR effect. We conclude that CR is a valid phenomenon in rodents that cannot be explained by changes in protein intake, but that there is a separate phenomenon linking protein intake to lifespan, which acts over a different range of protein intakes than is typical in CR studies. This suggests there may be a fundamental difference in the responses of insects and rodents to CR. This may be traced to differences in the physiology of these groups, or reflect a major methodological difference between 'restriction' studies performed on rodents and insects. We suggest that studies where the diet is supplied ad libitum, but diluted with inert components, should perhaps be

  4. Tunable magnetoresistance driven by magnetically sensitive negative differential resistance in an asymmetrically coupled single molecule junction

    Science.gov (United States)

    Warner, Ben; El Hallak, Fadi; Sharp, John; Persson, Mats; Fisher, Andrew J.; Hirjibehedin, Cyrus F.

    2014-03-01

    Using scanning tunneling microscopy, we study the effects of interactions between individual magnetic molecules that are separated from an underlying copper surface by a thin-insulating layer of copper nitride (Cu2N). For electrical transport through a junction containing an individual iron phthalocyanine (FePc) molecule on Cu2N, we observe two novel magnetoresistance behaviors that arise from negative differential resistance (NDR) that shifts by unexpectedly large amounts in a magnetic field. Because voltage is dropped asymmetrically in this double barrier junction, the FePc can become transiently charged when its states are aligned with the Fermi energy of the Cu, resulting in the observed NDR effect. Furthermore, the asymmetric coupling magnifies the observed voltage sensitivity of the magnetic field dependence of the NDR - which inherently is on the scale of the Zeeman energy - by almost two orders of magnitude. These findings represent a new basis for making magnetoresistance devices at the single molecule scale. Furthermore, the enhancement of the energy scales created by asymmetric coupling of the junction can be combined with other multi-step tunneling processes to allow for the investigation of other phenomena that normally would be difficult to observe.

  5. The multiplier effect : how the accumulation of cultural and social capital explains steep upward social mobility of children of low-educated immigrants

    NARCIS (Netherlands)

    Crul, Maurice; Schneider, Jens; Keskiner, Elif; Lelie, Frans

    2017-01-01

    We introduce what we have coined the multiplier effect. We explain the steep upward mobility of children of low-educated immigrants by studying how they overcome obstacles on their regular pathway, via alternative routes or through loopholes in the education and labour market system. The idea of the

  6. The Resilience of Dependency Effects in Explaining Income Inequality in the Global Economy: A Cross National Analysis, 1975-1995

    Directory of Open Access Journals (Sweden)

    Linda Beer

    2015-08-01

    Full Text Available The contemporary era is one of both accelerated economic globalization and rising inequality. There is an increasing awareness among both academic scholars and development professionals that globalization puts certain populations at risk. However, there has been inadequate theoretical analysis and a lack of up to date empirical studies that explain just how contemporary globalization a?ects inequality and the well being of individuals. This study explores the conditions under which TNC penetration and other globalization processes in?uence change in domestic income distribution. Its aim is to investigate whether theoretical models that have proven successful in explaining di?erences in income inequality cross-sectionally also allow for an understanding of the dynamics of income distribution during the 1980s and early 1990s, an era characterized by a dramatic acceleration of globalization. We present an analysis of change in national income distribution using linear regression models with a panel design. This study suggests that dependence on foreign investment as a development strategy, especially compared to domestic and human capital investment, may be misguided for nations concerned with equality. Net of other factors, foreign investment dependence bene?ts the elite segments of the income-earning population over the poorer eighty percent. Our analysis provides evidence of a shift in capital/labor relations brought about by globalization that has signi? cantly contributed to the rise in income inequality seen throughout the world.

  7. Matlab for engineers explained

    CERN Document Server

    Gustafsson, Fredrik

    2003-01-01

    This book is written for students at bachelor and master programs and has four different purposes, which split the book into four parts: 1. To teach first or early year undergraduate engineering students basic knowledge in technical computations and programming using MATLAB. The first part starts from first principles and is therefore well suited both for readers with prior exposure to MATLAB but lacking a solid foundational knowledge of the capabilities of the system and readers not having any previous experience with MATLAB. The foundational knowledge gained from these interactive guided tours of the system will hopefully be sufficient for an effective utilization of MATLAB in the engineering profession, in education and in research. 2. To explain the foundations of more advanced use of MATLAB using the facilities added the last couple of years, such as extended data structures, object orientation and advanced graphics. 3. To give an introduction to the use of MATLAB in typical undergraduate courses in elec...

  8. How to catch more prey with less effective traps: explaining the evolution of temporarily inactive traps in carnivorous pitcher plants.

    Science.gov (United States)

    Bauer, Ulrike; Federle, Walter; Seidel, Hannes; Grafe, T Ulmar; Ioannou, Christos C

    2015-02-22

    Carnivorous Nepenthes pitcher plants capture arthropods with specialized slippery surfaces. The key trapping surface, the pitcher rim (peristome), is highly slippery when wetted by rain, nectar or condensation, but not when dry. As natural selection should favour adaptations that maximize prey intake, the evolution of temporarily inactive traps seems paradoxical. Here, we show that intermittent trap deactivation promotes 'batch captures' of ants. Prey surveys revealed that N. rafflesiana pitchers sporadically capture large numbers of ants from the same species. Continuous experimental wetting of the peristome increased the number of non-recruiting prey, but decreased the number of captured ants and shifted their trapping mode from batch to individual capture events. Ant recruitment was also lower to continuously wetted pitchers. Our experimental data fit a simple model that predicts that intermittent, wetness-based trap activation should allow safe access for 'scout' ants under dry conditions, thereby promoting recruitment and ultimately higher prey numbers. The peristome trapping mechanism may therefore represent an adaptation for capturing ants. The relatively rare batch capture events may particularly benefit larger plants with many pitchers. This explains why young plants of many Nepenthes species additionally employ wetness-independent, waxy trapping surfaces.

  9. Transgenerational effects of mild heat in Arabidopsis thaliana show strong genotype specificity that is explained by climate at origin.

    Science.gov (United States)

    Groot, Maartje P; Kubisch, Alexander; Ouborg, N Joop; Pagel, Jörn; Schmid, Karl J; Vergeer, Philippine; Lampei, Christian

    2017-08-01

    Transgenerational environmental effects can trigger strong phenotypic variation. However, it is unclear how cues from different preceding generations interact. Also, little is known about the genetic variation for these life history traits. Here, we present the effects of grandparental and parental mild heat, and their combination, on four traits of the third-generation phenotype of 14 Arabidopsis thaliana genotypes. We tested for correlations of these effects with climate and constructed a conceptual model to identify the environmental conditions that favour the parental effect on flowering time. We observed strong evidence for genotype-specific transgenerational effects. On average, A. thaliana accustomed to mild heat produced more seeds after two generations. Parental effects overruled grandparental effects in all traits except reproductive biomass. Flowering was generally accelerated by all transgenerational effects. Notably, the parental effect triggered earliest flowering in genotypes adapted to dry summers. Accordingly, this parental effect was favoured in the model when early summer heat terminated the growing season and environments were correlated across generations. Our results suggest that A. thaliana can partly accustom to mild heat over two generations and genotype-specific parental effects show non-random evolutionary divergence across populations that may support climate change adaptation in the Mediterranean. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  10. Climate change effects on enchytraeid performance in metal-polluted soils explained from changes in metal bioavailability and bioaccumulation.

    Science.gov (United States)

    González-Alcaraz, M Nazaret; van Gestel, Cornelis A M

    2015-10-01

    Climate change may alter physical, chemical and biological properties of ecosystems, affecting organisms but also the fate of chemical pollutants. This study aimed to find out how changes in climate conditions (air temperature, soil moisture content) affect the toxicity of metal-polluted soils to the soft-bodied soil organism Enchytraeus crypticus, linking enchytraeid performance with changes in soil available and body metal concentrations. Bioassays with E. crypticus were performed under different combinations of air temperature (20 and 25 °C) and soil moisture content (50% and 30% of the soil water holding capacity, WHC) in dilution series of three metal-polluted soils (mine tailing, forest and watercourse). After 21 d exposure, enchytraeid reproduction was determined, and soil available (extracted with 0.01 M CaCl2) and body Cd, Cu, Pb and Zn concentrations in surviving adults were determined. In general, Cd, Pb and Zn availability decreased upon incubation under the different climate scenarios. In the watercourse soil, with initially higher available metal concentrations (678 µg Cd kg(-1), 807 µg Pb kg(-1) and 31,020 µg Zn kg(-1)), decreases were greatest at 50% WHC probably due to metal immobilization as carbonates. Enchytraeid reproduction was negatively affected by higher available metal concentrations, with reductions up to 98% in the watercourse soil compared to the control soil at 30% WHC. Bioaccumulation of Cd, Pb and Zn was higher when drier conditions were combined with the higher temperature of 25 °C. Changes in metal bioavailability and bioaccumulation explained the toxicity of soil polluted by metal mine wastes to enchytraeids under changing environmental conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Plagiarism explainer for students

    OpenAIRE

    Barba, Lorena A.

    2016-01-01

    A slide deck to serve as an explainer of plagiarism in academic settings, with a personal viewpoint. For my students.Also on SpeakerDeck:https://speakerdeck.com/labarba/plagiarism-explainer-for-students(The slide viewer on SpeakerDeck is much nicer.)

  12. Explaining Social Class Inequalities in Educational Achievement in the UK: Quantifying the Contribution of Social Class Differences in School "Effectiveness"

    Science.gov (United States)

    Hobbs, Graham

    2016-01-01

    There are large social class inequalities in educational achievement in the UK. This paper quantifies the contribution of one mechanism to the production of these inequalities: social class differences in school "effectiveness," where "effectiveness" refers to a school's impact on pupils' educational achievement (relative to…

  13. Identification of Metabolic Pathways in Daphnia magna Explaining Hormetic Effects of Selective Serotonin Reuptake Inhibitors and 4-Nonylphenol Using Transcriptomic and Phenotypic Responses

    OpenAIRE

    Campos, Bruno; Garcia-Reyero, Natalia; Rivetti, Claudia; Escalon, Lynn; Habib, Tanwir; Tauler, Roma; Tsakovski, Stefan; Pina, Benjamin; Barata, Carlos

    2013-01-01

    The molecular mechanisms explaining hormetic effects of selective serotonin reuptake inhibitors (SSRIs) and 4-nonylphenol in Daphnia magna reproduction were studied in juveniles and adults. Transcriptome analyses showed changes in mRNA levels for 1,796 genes in juveniles and 1,214 genes in adults (out of 15,000 total probes) exposed to two SSRIs (fluoxetine and fluvoxamine) or to 4-nonylphenol. Functional annotation of affected genes was improved by assuming the annotations of putatively homo...

  14. Integration in the Ranks: Explaining the Effects of Social Pressure and Attitudinal Change on U.S. Military Policy

    National Research Council Canada - National Science Library

    Bailey, Jr., Richard J

    2006-01-01

    .... First, a cross-national quantitative analysis examined the effects of values systems, military need, and other characteristics on the likelihood of a nation adopting a full-inclusion policy, thereby...

  15. A model of human motor sequence learning explains facilitation and interference effects based on spike-timing dependent plasticity.

    Directory of Open Access Journals (Sweden)

    Quan Wang

    2017-08-01

    Full Text Available The ability to learn sequential behaviors is a fundamental property of our brains. Yet a long stream of studies including recent experiments investigating motor sequence learning in adult human subjects have produced a number of puzzling and seemingly contradictory results. In particular, when subjects have to learn multiple action sequences, learning is sometimes impaired by proactive and retroactive interference effects. In other situations, however, learning is accelerated as reflected in facilitation and transfer effects. At present it is unclear what the underlying neural mechanism are that give rise to these diverse findings. Here we show that a recently developed recurrent neural network model readily reproduces this diverse set of findings. The self-organizing recurrent neural network (SORN model is a network of recurrently connected threshold units that combines a simplified form of spike-timing dependent plasticity (STDP with homeostatic plasticity mechanisms ensuring network stability, namely intrinsic plasticity (IP and synaptic normalization (SN. When trained on sequence learning tasks modeled after recent experiments we find that it reproduces the full range of interference, facilitation, and transfer effects. We show how these effects are rooted in the network's changing internal representation of the different sequences across learning and how they depend on an interaction of training schedule and task similarity. Furthermore, since learning in the model is based on fundamental neuronal plasticity mechanisms, the model reveals how these plasticity mechanisms are ultimately responsible for the network's sequence learning abilities. In particular, we find that all three plasticity mechanisms are essential for the network to learn effective internal models of the different training sequences. This ability to form effective internal models is also the basis for the observed interference and facilitation effects. This suggests that

  16. A model of human motor sequence learning explains facilitation and interference effects based on spike-timing dependent plasticity.

    Science.gov (United States)

    Wang, Quan; Rothkopf, Constantin A; Triesch, Jochen

    2017-08-01

    The ability to learn sequential behaviors is a fundamental property of our brains. Yet a long stream of studies including recent experiments investigating motor sequence learning in adult human subjects have produced a number of puzzling and seemingly contradictory results. In particular, when subjects have to learn multiple action sequences, learning is sometimes impaired by proactive and retroactive interference effects. In other situations, however, learning is accelerated as reflected in facilitation and transfer effects. At present it is unclear what the underlying neural mechanism are that give rise to these diverse findings. Here we show that a recently developed recurrent neural network model readily reproduces this diverse set of findings. The self-organizing recurrent neural network (SORN) model is a network of recurrently connected threshold units that combines a simplified form of spike-timing dependent plasticity (STDP) with homeostatic plasticity mechanisms ensuring network stability, namely intrinsic plasticity (IP) and synaptic normalization (SN). When trained on sequence learning tasks modeled after recent experiments we find that it reproduces the full range of interference, facilitation, and transfer effects. We show how these effects are rooted in the network's changing internal representation of the different sequences across learning and how they depend on an interaction of training schedule and task similarity. Furthermore, since learning in the model is based on fundamental neuronal plasticity mechanisms, the model reveals how these plasticity mechanisms are ultimately responsible for the network's sequence learning abilities. In particular, we find that all three plasticity mechanisms are essential for the network to learn effective internal models of the different training sequences. This ability to form effective internal models is also the basis for the observed interference and facilitation effects. This suggests that STDP, IP, and SN

  17. Do Health Behaviors Explain the Effect of Neuroticism on Mortality? Longitudinal Findings from the VA Normative Aging Study

    Science.gov (United States)

    Mroczek, Daniel K.; Spiro, Avron; Turiano, Nick

    2009-01-01

    Studies have shown that higher levels of neuroticism are associated with greater risk of mortality. Yet what accounts for this association? One major theoretical position holds that persons higher in neuroticism engage in poorer health behaviors, such as smoking and excessive drinking, thus leading to earlier death. We tested this hypothesis using 30-year mortality in 1,788 men from the VA Normative Aging Study. Using proportional hazards (Cox) models we found that one health behavior, smoking, attenuated the effect of neuroticism on mortality by 40%. However, 60% remained unexplained, suggesting that the effects of other pathways (e.g., biological) also influence the relationship between neuroticism and mortality. PMID:20161240

  18. Estimating and explaining the effect of education and income on head and neck cancer risk: INHANCE consortium pooled analysis of 31 case-control studies from 27 countries

    Science.gov (United States)

    Conway, David I.; Brenner, Darren R.; McMahon, Alex D.; Macpherson, Lorna M.D.; Agudo, Antonio; Ahrens, Wolfgang; Bosetti, Cristina; Brenner, Hermann; Castellsague, Xavier; Chen, Chu; Curado, Maria Paula; Curioni, Otávio A.; Maso, Luigino Dal; Daudt, Alexander W.; de Gois Filho, José F.; D'Souza, Gypsyamber; Edefonti, Valeria; Fabianova, Eleonora; Fernandez, Leticia; Franceschi, Silvia; Gillison, Maura; Hayes, Richard B.; Healy, Claire M.; Herrero, Rolando; Holcatova, Ivana; Jayaprakash, Vijayvel; Kelsey, Karl; Kjaerheim, Kristina; Koifman, Sergio; La Vecchia, Carlo; Lagiou, Pagona; Lazarus, Philip; Levi, Fabio; Lissowska, Jolanta; Luce, Daniele; Macfarlane, Tatiana V.; Mates, Dana; Matos, Elena; McClean, Michael; Menezes, Ana M; Menvielle, Gwenn; Merletti, Franco; Morgenstern, Hal; Moysich, Kirsten; Müller, Heiko; Muscat, Joshua; Olshan, Andrew F.; Purdue, Mark P.; Ramroth, Heribert; Richiardi, Lorenzo; Rudnai, Peter; Schantz, Stimson; Schwartz, Stephen M.; Shangina, Oxana; Simonato, Lorenzo; Smith, Elaine; Stucker, Isabelle; Sturgis, Erich M.; Szeszenia-Dabrowska, Neonila; Talamini, Renato; Thomson, Peter; Vaughan, Thomas L.; Wei, Qingyi; Winn, Deborah M.; Wunsch-Filho, Victor; Yu, Guo-Pei; Zhang, Zuo-Feng; Zheng, Tongzhang; Znaor, Ariana; Boffetta, Paolo; Chuang, Shu-Chun; Ghodrat, Marianoosh; Lee, Yuan-Chin Amy; Hashibe, Mia; Brennan, Paul

    2015-01-01

    Low socioeconomic status has been reported to be associated with head and neck cancer risk. However, previous studies have been too small to examine the associations by cancer subsite, age, sex, global region and calendar time and to explain the association in terms of behavioral risk factors. Individual participant data of 23,964 cases with head and neck cancer and 31,954 controls from 31 studies in 27 countries pooled with random effects models. Overall, low education was associated with an increased risk of head and neck cancer (OR = 2.50; 95% CI = 2.02 – 3.09). Overall one-third of the increased risk was not explained by differences in the distribution of cigarette smoking and alcohol behaviors; and it remained elevated among never users of tobacco and nondrinkers (OR = 1.61; 95% CI = 1.13 – 2.31). More of the estimated education effect was not explained by cigarette smoking and alcohol behaviors: in women than in men, in older than younger groups, in the oropharynx than in other sites, in South/Central America than in Europe/North America and was strongest in countries with greater income inequality. Similar findings were observed for the estimated effect of low versus high household income. The lowest levels of income and educational attainment were associated with more than 2-fold increased risk of head and neck cancer, which is not entirely explained by differences in the distributions of behavioral risk factors for these cancers and which varies across cancer sites, sexes, countries and country income inequality levels. PMID:24996155

  19. Estimating and explaining the effect of education and income on head and neck cancer risk: INHANCE consortium pooled analysis of 31 case-control studies from 27 countries.

    Science.gov (United States)

    Conway, David I; Brenner, Darren R; McMahon, Alex D; Macpherson, Lorna M D; Agudo, Antonio; Ahrens, Wolfgang; Bosetti, Cristina; Brenner, Hermann; Castellsague, Xavier; Chen, Chu; Curado, Maria Paula; Curioni, Otávio A; Dal Maso, Luigino; Daudt, Alexander W; de Gois Filho, José F; D'Souza, Gypsyamber; Edefonti, Valeria; Fabianova, Eleonora; Fernandez, Leticia; Franceschi, Silvia; Gillison, Maura; Hayes, Richard B; Healy, Claire M; Herrero, Rolando; Holcatova, Ivana; Jayaprakash, Vijayvel; Kelsey, Karl; Kjaerheim, Kristina; Koifman, Sergio; La Vecchia, Carlo; Lagiou, Pagona; Lazarus, Philip; Levi, Fabio; Lissowska, Jolanta; Luce, Daniele; Macfarlane, Tatiana V; Mates, Dana; Matos, Elena; McClean, Michael; Menezes, Ana M; Menvielle, Gwenn; Merletti, Franco; Morgenstern, Hal; Moysich, Kirsten; Müller, Heiko; Muscat, Joshua; Olshan, Andrew F; Purdue, Mark P; Ramroth, Heribert; Richiardi, Lorenzo; Rudnai, Peter; Schantz, Stimson; Schwartz, Stephen M; Shangina, Oxana; Simonato, Lorenzo; Smith, Elaine; Stucker, Isabelle; Sturgis, Erich M; Szeszenia-Dabrowska, Neonila; Talamini, Renato; Thomson, Peter; Vaughan, Thomas L; Wei, Qingyi; Winn, Deborah M; Wunsch-Filho, Victor; Yu, Guo-Pei; Zhang, Zuo-Feng; Zheng, Tongzhang; Znaor, Ariana; Boffetta, Paolo; Chuang, Shu-Chun; Ghodrat, Marianoosh; Amy Lee, Yuan-Chin; Hashibe, Mia; Brennan, Paul

    2015-03-01

    Low socioeconomic status has been reported to be associated with head and neck cancer risk. However, previous studies have been too small to examine the associations by cancer subsite, age, sex, global region and calendar time and to explain the association in terms of behavioral risk factors. Individual participant data of 23,964 cases with head and neck cancer and 31,954 controls from 31 studies in 27 countries pooled with random effects models. Overall, low education was associated with an increased risk of head and neck cancer (OR = 2.50; 95% CI = 2.02 - 3.09). Overall one-third of the increased risk was not explained by differences in the distribution of cigarette smoking and alcohol behaviors; and it remained elevated among never users of tobacco and nondrinkers (OR = 1.61; 95% CI = 1.13 - 2.31). More of the estimated education effect was not explained by cigarette smoking and alcohol behaviors: in women than in men, in older than younger groups, in the oropharynx than in other sites, in South/Central America than in Europe/North America and was strongest in countries with greater income inequality. Similar findings were observed for the estimated effect of low versus high household income. The lowest levels of income and educational attainment were associated with more than 2-fold increased risk of head and neck cancer, which is not entirely explained by differences in the distributions of behavioral risk factors for these cancers and which varies across cancer sites, sexes, countries and country income inequality levels. © 2014 UICC.

  20. Does Parenting Explain the Effects of Structural Conditions on Children's Antisocial Behavior? A Comparison of Blacks and Whites.

    Science.gov (United States)

    McLeod, Jane D.; And Others

    1994-01-01

    Data on black children and white children over age six and their mothers (from National Longitudinal Survey of Youth) indicate no racial differences in total effects of poverty and single parenthood on parenting practices (affection and spanking). Parenting practices were reciprocally related to child's antisocial behavior for whites, but did not…

  1. Mixture effects of nickel and chlorpyrifos on Folsomia candida (Collembola) explained from development of toxicity in time.

    NARCIS (Netherlands)

    Broerse, M.; van Gestel, C.A.M.

    2010-01-01

    Two reference models are commonly used to predict mixture toxicity, Concentration Addition and Independent Action. For accurately predicting mixture effects, both reference models need a full description of the dose-response curve for all single chemicals present in the mixture. We studied the

  2. Does Academic and Social Self-Concept and Motivation Explain the Effect of Grading on Students' Achievement?

    Science.gov (United States)

    Klapp, Alli

    2018-01-01

    The purpose of the study was to investigate if academic and social self-concept and motivation to improve in academic school subjects mediated the negative effect of summative assessment (grades) for low-ability students' achievement in compulsory school. In two previous studies, summative assessment (grading) was found to have a differentiating…

  3. The Role of Gist and Verbatim Memory in Complex Decision Making: Explaining the Unconscious-Thought Effect

    Science.gov (United States)

    Abadie, Marlène; Waroquier, Laurent; Terrier, Patrice

    2017-01-01

    Previous research showed that the "unconscious-thought effect", which refers to an improvement in complex decision making following a distraction period, was moderated by the presentation format of pieces of information about different options. The aim of the current study was to replicate this finding and further examine the memory…

  4. Manganese distribution and speciation help to explain the effects of silicate and phosphate on manganese toxicity in four crop species.

    Science.gov (United States)

    Blamey, F Pax C; McKenna, Brigid A; Li, Cui; Cheng, Miaomiao; Tang, Caixian; Jiang, Haibo; Howard, Daryl L; Paterson, David J; Kappen, Peter; Wang, Peng; Menzies, Neal W; Kopittke, Peter M

    2018-02-01

    Soil acidity and waterlogging increase manganese (Mn) in leaf tissues to potentially toxic concentrations, an effect reportedly alleviated by increased silicon (Si) and phosphorus (P) supply. Effects of Si and P on Mn toxicity were studied in four plant species using synchrotron-based micro X-ray fluorescence (μ-XRF) and nanoscale secondary ion mass spectrometry (NanoSIMS) to determine Mn distribution in leaf tissues and using synchrotron-based X-ray absorption spectroscopy (XAS) to measure Mn speciation in leaves, stems and roots. A concentration of 30 μM Mn in solution was toxic to cowpea and soybean, with 400 μM Mn toxic to sunflower but not white lupin. Unexpectedly, μ-XRF analysis revealed that 1.4 mM Si in solution decreased Mn toxicity symptoms through increased Mn localization in leaf tissues. NanoSIMS showed Mn and Si co-localized in the apoplast of soybean epidermal cells and basal cells of sunflower trichomes. Concomitantly, added Si decreased oxidation of Mn(II) to Mn(III) and Mn(IV). An increase from 5 to 50 μM P in solution changed some Mn toxicity symptoms but had little effect on Mn distribution or speciation. We conclude that Si increases localized apoplastic sorption of Mn in cowpea, soybean and sunflower leaves thereby decreasing free Mn 2+ accumulation in the apoplast or cytoplasm. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  5. Explaining the high voice superiority effect in polyphonic music: evidence from cortical evoked potentials and peripheral auditory models.

    Science.gov (United States)

    Trainor, Laurel J; Marie, Céline; Bruce, Ian C; Bidelman, Gavin M

    2014-02-01

    Natural auditory environments contain multiple simultaneously-sounding objects and the auditory system must parse the incoming complex sound wave they collectively create into parts that represent each of these individual objects. Music often similarly requires processing of more than one voice or stream at the same time, and behavioral studies demonstrate that human listeners show a systematic perceptual bias in processing the highest voice in multi-voiced music. Here, we review studies utilizing event-related brain potentials (ERPs), which support the notions that (1) separate memory traces are formed for two simultaneous voices (even without conscious awareness) in auditory cortex and (2) adults show more robust encoding (i.e., larger ERP responses) to deviant pitches in the higher than in the lower voice, indicating better encoding of the former. Furthermore, infants also show this high-voice superiority effect, suggesting that the perceptual dominance observed across studies might result from neurophysiological characteristics of the peripheral auditory system. Although musically untrained adults show smaller responses in general than musically trained adults, both groups similarly show a more robust cortical representation of the higher than of the lower voice. Finally, years of experience playing a bass-range instrument reduces but does not reverse the high voice superiority effect, indicating that although it can be modified, it is not highly neuroplastic. Results of new modeling experiments examined the possibility that characteristics of middle-ear filtering and cochlear dynamics (e.g., suppression) reflected in auditory nerve firing patterns might account for the higher-voice superiority effect. Simulations show that both place and temporal AN coding schemes well-predict a high-voice superiority across a wide range of interval spacings and registers. Collectively, we infer an innate, peripheral origin for the higher-voice superiority observed in human

  6. Effects of Photobiomodulation on SOFAT, a T-cell-derived Cytokine, May Explain Accelerated Orthodontic Tooth Movement.

    Science.gov (United States)

    Jettar, Viviane; Napimoga, Marcelo; Freitas, Fabiana; Clemente-Napimoga, Juliana; Suzuki, Selly; Montalli, Victor; Garcez, Aguinaldo

    2017-12-23

    Orthodontic tooth movement is based on mechanical forces inducing bone remodeling and several methods have been proposed to increase tooth movement, including photobiomodulation. This study evaluated, in an animal model, the effects of photobiomodulation on SOFAT - a secreted osteoclastogenic factor of activated T cells and RANK-L during tooth movement. The results showed that tooth displacement, RANK-L and SOFAT levels were significantly greater compared to control group. SOFAT may play an important role in bone remodeling during orthodontic movement, possibly increasing the osteoclast cells at the compression area and bone remodeling activity. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  7. Acute psychoactive and toxic effects of D. metel on mice explained by 1H NMR based metabolomics approach.

    Science.gov (United States)

    Fu, Yonghong; Si, Zhihong; Li, Pumin; Li, Minghui; Zhao, He; Jiang, Lei; Xing, Yuexiao; Hong, Wei; Ruan, Lingyu; Wang, Jun-Song

    2017-08-01

    Datura metel L. (D. metel) is one well-known folk medical herb with wide application and also the most abused plants all over the world, mainly for spiritual or religious purpose, over-dosing of which often produces poisonous effects. In this study, mice were orally administered with the extract of D. metel once a day at doses for 10 mg/kg and 40 mg/kg for consecutive 4 days, 1 H NMR based metabolomics approach aided with histopathological inspection and biochemical assays were used for the first time to study the psychoactive and toxic effects of D. metel. Histopathological inspection revealed obvious hypertrophy of hepatocytes, karyolysis and karyorrhexis in livers as well as distinct nerve cell edema, chromatolysis and lower nuclear density in brains. The increased tissue level of methane dicarboxylic aldehyde (MDA) and superoxide dismutase (SOD), decreased tissue level of glutathione (GSH) along with increased serum level of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) suggested brain and liver injury induced by D. metel. Orthogonal signal correction-partial least squares-discriminant analysis (OSC-PLS-DA) of NMR profiles supplemented with correlation network analysis revealed significant altered metabolites and related pathway that contributed to oxidative stress, energy metabolism disturbances, neurotransmitter imbalance and amino acid metabolism disorders.

  8. The extent of using mobility assistive devices can partly explain fatigue among persons with late effects of polio - a retrospective registry study in Sweden.

    Science.gov (United States)

    Santos Tavares Silva, I; Sunnerhagen, K S; Willén, C; Ottenvall Hammar, I

    2016-11-18

    Fatigue is reported as one of the most disabling symptoms and is common among persons living with late effects of polio. Although fatigue has been studied in the context of people living with late effects of polio, there is a lack of knowledge concerning the association of fatigue and variables of importance for participation in daily life. Therefore, the aim of this study was to explore possible factors associated with fatigue among persons with late effects of polio in Sweden. This retrospective registry study consisted of 89 persons with late effects of polio living in Sweden. Fatigue was measured with the Multidimensional Fatigue Inventory (MFI-20) scale, Swedish version. Pearson's correlation coefficient was used to analyse the correlation between the factors and fatigue, and a multiple linear regression was carried out to explore factors for fatigue. Fatigue statistically significantly correlated with age (r = 0.234, p polio, and the model partly explained 14% of the variation of fatigue. Fatigue could partly be explained by the extent of using mobility assistive devices and age. Healthcare professionals should provide and demonstrate the importance of assistive devices to ensure management of fatigue in persons living with late effects of polio.

  9. A hierarchy of timescales explains distinct effects of local inhibition of primary visual cortex and frontal eye fields.

    Science.gov (United States)

    Cocchi, Luca; Sale, Martin V; L Gollo, Leonardo; Bell, Peter T; Nguyen, Vinh T; Zalesky, Andrew; Breakspear, Michael; Mattingley, Jason B

    2016-09-06

    Within the primate visual system, areas at lower levels of the cortical hierarchy process basic visual features, whereas those at higher levels, such as the frontal eye fields (FEF), are thought to modulate sensory processes via feedback connections. Despite these functional exchanges during perception, there is little shared activity between early and late visual regions at rest. How interactions emerge between regions encompassing distinct levels of the visual hierarchy remains unknown. Here we combined neuroimaging, non-invasive cortical stimulation and computational modelling to characterize changes in functional interactions across widespread neural networks before and after local inhibition of primary visual cortex or FEF. We found that stimulation of early visual cortex selectively increased feedforward interactions with FEF and extrastriate visual areas, whereas identical stimulation of the FEF decreased feedback interactions with early visual areas. Computational modelling suggests that these opposing effects reflect a fast-slow timescale hierarchy from sensory to association areas.

  10. The balanced ideological antipathy model: explaining the effects of ideological attitudes on inter-group antipathy across the political spectrum.

    Science.gov (United States)

    Crawford, Jarret T; Mallinas, Stephanie R; Furman, Bryan J

    2015-12-01

    We introduce the balanced ideological antipathy (BIA) model, which challenges assumptions that right-wing authoritarianism (RWA) and social dominance orientation (SDO) predict inter-group antipathy per se. Rather, the effects of RWA and SDO on antipathy should depend on the target's political orientation and political objectives, the specific components of RWA, and the type of antipathy expressed. Consistent with the model, two studies (N = 585) showed that the Traditionalism component of RWA positively and negatively predicted both political intolerance and prejudice toward tradition-threatening and -reaffirming groups, respectively, whereas SDO positively and negatively predicted prejudice (and to some extent political intolerance) toward hierarchy-attenuating and -enhancing groups, respectively. Critically, the Conservatism component of RWA positively predicted political intolerance (but not prejudice) toward each type of target group, suggesting it captures the anti-democratic impulse at the heart of authoritarianism. Recommendations for future research on the relationship between ideological attitudes and inter-group antipathy are discussed. © 2015 by the Society for Personality and Social Psychology, Inc.

  11. Explaining the isotope effect on heat transport in L-mode with the collisional electron-ion energy exchange

    Science.gov (United States)

    Schneider, P. A.; Bustos, A.; Hennequin, P.; Ryter, F.; Bernert, M.; Cavedon, M.; Dunne, M. G.; Fischer, R.; Görler, T.; Happel, T.; Igochine, V.; Kurzan, B.; Lebschy, A.; McDermott, R. M.; Morel, P.; Willensdorfer, M.; the ASDEX Upgrade Team; The EUROfusion MST1 Team

    2017-06-01

    In ASDEX Upgrade (AUG), the normalised gyroradius {ρ\\star} was varied via a hydrogen isotope scan while keeping other dimensionless parameters constant. This was done in L-mode, to minimise the impact of pedestal stability on confinement. Power balance and perturbative transport analyses reveal that the electron heat transport is unaffected by the differences in isotope mass. Nonlinear simulations with the Gene code suggest that these L-mode discharges are ion temperature gradient (ITG) dominated. The different gyroradii due to the isotope mass do not necessarily result in a change of the predicted heat fluxes. This result is used in simulations with the Astra transport code to match the experimental profiles. In these simulations the experimental profiles and confinement times are reproduced with the same transport coefficients for hydrogen and deuterium plasmas. The mass only enters in the energy exchange term between electrons and ions. These numerical observations are supported by additional experiments which show a lower ion energy confinement compared to that of the electrons. Additionally, hydrogen and deuterium plasmas have a similar confinement when the energy exchange time between electrons and ions is matched. This strongly suggests that the observed isotope dependence in L-mode is not dominated by a gyroradius effect, but a consequence of the mass dependence in the collisional energy exchange between electrons and ions.

  12. How to train your Bayesian: a problem-representation transfer rather than a format-representation shift explains training effects.

    Science.gov (United States)

    Sirota, Miroslav; Kostovičová, Lenka; Vallée-Tourangeau, Frédéric

    2015-01-01

    People improve their Bayesian reasoning most when they are trained to represent single-event probabilities as natural frequencies; nevertheless, the underlying mechanism of this representational training remains unclear. Several authors suggested that people learn to shift the initial format to natural frequencies, and improve their reasoning because natural frequencies align with an evolutionary designed frequency-coding mechanism--the format-representation shift hypothesis. Alternatively, people may acquire a generic problem representation in terms of nested sets that is then transferred to similar problems--the problem-representation transfer hypothesis. To disentangle the effect of the format shift from problem representation transfer, we devised two types of training with problems featuring a nonfrequency format and a concealed nested-sets structure. Participants learnt the adequate problem representation in both training manipulations, but in only one did they learn, in addition, to shift the format to frequencies. Substantial evidence (BF01 = 5, where BF = Bayes factor) indicates that both types of training improved reasoning in an immediate and a one-week follow-up posttest to the same extent. Such findings support the problem-representation transfer hypothesis because learning an adequate nested-sets problem representation accounts for the performance improvement, whereas the frequency format per se confers no additional benefit. We discuss the implications of these findings for two dominant accounts of statistical reasoning.

  13. Effects of systematic asymmetric discounting on physician-patient interactions: a theoretical framework to explain poor compliance with lifestyle counseling

    Directory of Open Access Journals (Sweden)

    Fleischer Alan B

    2002-11-01

    Full Text Available Abstract Background This study advances the use of a utility model to model physician-patient interactions from the perspectives of physicians and patients. Presentation of the hypothesis In cases involving acute care, patient counseling involves a relatively straightforward transfer of information from the physician to a patient. The patient has less information than the physician on the impact the condition and its treatment have on utility. In decisions involving lifestyle changes, the patient may have more information than the physician on his/her utility of consumption; moreover, differences in discounting future health may contribute significantly to differences between patients' preferences and physicians' recommendations. Testing the hypothesis The expectation of differences in internal discount rate between patients and their physicians is discussed. Implications of the hypothesis This utility model provides a conceptual basis for the finding that educational approaches alone may not effect changes in patient behavior and suggests other economic variables that could be targeted in the attempt to produce healthier behavior.

  14. A new perspective of neuromyopathy to explain intractable pancreatic cancer pains; Dry needling as an effective adjunct to neurolytic blocks

    Directory of Open Access Journals (Sweden)

    Lakshmi Vas

    2016-01-01

    Full Text Available We present a new perspective of neuromyopathy in pancreatic cancer pain (PCP referral to bodywall; proposal of new rationale to include ultrasound guided dry needling (USGDN of body wall muscles as an effective adjunct to neurolytic coeliac plexus block (NCPB or splanchnic nerve radiofrequency ablation (SRF for comprehensive interventional management. Methods: PCP response to SRF in 2 patients and NCPB in 3 patients was documented on numerical rating scale (NRS on post procedure days 3 and 15. If the residual pain was >5 NRS on day 15, USGDN of abdominal and back muscles was started on a thrice weekly basis. The response to USGDN documented on day 30 after approximately 6 sessions of DN, showed a significant pain reduction (0-2 NRS with 50% reduction of pre-treatment opioid consumption. This was sustained at 6 months or till their demise. Convergence of visceral and somatic nerves at the dorsal horn (viscerosomatic neurons causes referral of visceral pain to the back and abdominal muscles. This leads to formation of myofascial trigger points (MTrPs in the muscles which sets up a parallel network of sensitized peripheral and central motor nociceptive processing (neuromyopathy. USGDN specifically addressed the MTrPs that develop as an epiphenomenon of self-perpetuating neuromyopathy while SRF/NCPB, analgesics and neuromodulators could address only visceral nociceptive afferents (pain mediated through celiac plexus which forms a meagre 10% of the total spinal cord afferent input. Thus, we conclude that combination of neuromyopathy and viscerosomatic convergence in PCP indicate a specific role for DN as an adjunct to SRF/NCPB in our patients

  15. Increased Back-Bonding Explains Step-Edge Reactivity and Particle Size Effect for CO Activation on Ru Nanoparticles.

    Science.gov (United States)

    Foppa, Lucas; Copéret, Christophe; Comas-Vives, Aleix

    2016-12-28

    Carbon monoxide is a ubiquitous molecule, a key feedstock and intermediate in chemical processes. Its adsorption and activation, typically carried out on metallic nanoparticles (NPs), are strongly dependent on the particle size. In particular, small NPs, which in principle contain more corner and step-edge atoms, are surprisingly less reactive than larger ones. Hereby, first-principles calculations on explicit Ru NP models (1-2 nm) show that both small and large NPs can present step-edge sites (e.g., B 5 and B 6 sites). However, such sites display strong particle-size-dependent reactivity because of very subtle differences in local chemical bonding. State-of-the-art crystal orbital Hamilton population analysis allows a detailed molecular orbital picture of adsorbed CO on step-edges, which can be classified as flat (η 1 coordination) and concave (η 2 coordination) sites. Our analysis shows that the CO π-metal d π hybrid band responsible for the electron back-donation is better represented by an oxygen lone pair on flat sites, whereas it is delocalized on both C and O atoms on concave sites, increasing the back-bonding on these sites compared to flat step-edges or low-index surface sites. The bonding analysis also rationalizes why CO cleavage is easier on step-edge sites of large NPs compared to small ones irrespective of the site geometry. The lower reactivity of small NPs is due to the smaller extent of the Ru-O interaction in the η 2 adsorption mode, which destabilizes the η 2 transition-state structure for CO direct cleavage. Our findings provide a molecular understanding of the reactivity of CO on NPs, which is consistent with the observed particle size effect.

  16. Computer jargon explained

    CERN Document Server

    Enticknap, Nicholas

    2014-01-01

    Computer Jargon Explained is a feature in Computer Weekly publications that discusses 68 of the most commonly used technical computing terms. The book explains what the terms mean and why the terms are important to computer professionals. The text also discusses how the terms relate to the trends and developments that are driving the information technology industry. Computer jargon irritates non-computer people and in turn causes problems for computer people. The technology and the industry are changing so rapidly; it is very hard even for professionals to keep updated. Computer people do not

  17. The wireless internet explained

    CERN Document Server

    Rhoton, John

    2001-01-01

    The Wireless Internet Explained covers the full spectrum of wireless technologies from a wide range of vendors, including initiatives by Microsoft and Compaq. The Wireless Internet Explained takes a practical look at wireless technology. Rhoton explains the concepts behind the physics, and provides an overview that clarifies the convoluted set of standards heaped together under the umbrella of wireless. It then expands on these technical foundations to give a panorama of the increasingly crowded landscape of wireless product offerings. When it comes to actual implementation the book gives abundant down-to-earth advice on topics ranging from the selection and deployment of mobile devices to the extremely sensitive subject of security.Written by an expert on Internet messaging, the author of Digital Press''s successful Programmer''s Guide to Internet Mail and X.400 and SMTP: Battle of the E-mail Protocols, The Wireless Internet Explained describes and evaluates the current state of the fast-growing and crucial...

  18. A Mediational Model Explaining the Connection Between Religiosity and Anti-Homosexual Attitudes in Italy: The Effects of Male Role Endorsement and Homosexual Stereotyping.

    Science.gov (United States)

    Piumatti, Giovanni

    2017-01-01

    This study aimed to better understand the relationship between religiosity and anti-homosexual attitudes in Italy by examining the mediation effects of male role endorsement and homosexual stereotyping. A sample of 5,522 Italian residents (age range = 18-74) was drawn from a cross-sectional national representative survey carried out in 2011. Measures included general religiosity, male role endorsement, homosexual stereotyping, social acceptance of homosexuality, and homosexual rights endorsement. Structural equation modeling was used to test the mediational effects of male role endorsement and homosexual stereotyping on the relationship between general religiosity and attitudes toward lesbians and gay men. Results showed that both male role endorsement and homosexual stereotyping partially mediated the relationship. In a model where religiosity and both mediators positively explained anti-homosexual attitudes, male role endorsement was the strongest mediator. Endorsement of gender role beliefs and homosexual stereotyping may thus exacerbate the connection between religiosity and anti-homosexual attitudes among Italians.

  19. Programme frequency, type, time and duration do not explain the effects of balance exercise in older adults: a systematic review with a meta-regression analysis.

    Science.gov (United States)

    Farlie, Melanie K; Robins, Lauren; Haas, Romi; Keating, Jennifer L; Molloy, Elizabeth; Haines, Terry P

    2018-01-25

    The objective of this systematic review was to examine the effects of different balance exercise interventions compared with non-balance exercise controls on balance task performance in older adults. Systematic review. Medline, Cumulative Index to Nursing and Allied Health Literature, EMBASE, Scopus and Cochrane Database of Systematic Reviews were searched until July 2017. Systematic reviews and meta-analyses of randomised trials of balance exercise interventions for older adults were identified for extraction of eligible randomised trials. Eligibility criteria for inclusion of randomised trials in meta-analyses were comparison of a balance exercise intervention with a control group that did not perform balance exercises, report of at least one end-intervention balance outcome measurement that was consistent with the five subgroups of balance exercise identified, and full-text article available in English. Ninety-five trials were included in meta-analyses and 80 in meta-regressions. For four balance exercise types (control centre of mass, multidimensional, mobility and reaching), significant effects for balance exercise interventions were found in meta-analyses (standardised mean difference (SMD) 0.31-0.50), however with considerable heterogeneity in observed effects (I 2 : 50.4%-80.6%). Risk of bias assessments (Physiotherapy Evidence Database score and funnel plots) did not explain heterogeneity. One significant relationship identified in the meta-regressions of SMD and balance exercise frequency, time and duration explained 2.1% of variance for the control centre of mass subgroup. Limitations to this study included the variability in design of balance interventions, incomplete reporting of data and statistical heterogeneity. The design of balance exercise programmes provides inadequate explanation of the observed benefits of these interventions. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights

  20. MAGMADIM: Young Explainers Program

    International Nuclear Information System (INIS)

    Paltiel, Z.

    2005-01-01

    Full Text:Physics teachers and educators constantly face the problem of inspiring their students to major in physics. On the other hand, science museums are designed to provide a pleasant environment which will stimulate and encourage a science associated experience to the general public. Typically, there is no intention to teach science as such in science museums. One may, however, use the science museum to teach and inspire certain groups of students in a much deeper sense. In fact they may actually enthusiastically learn much of the school physics curriculum at the museum. This report discusses the Magmadim program through which 10th graders are trained to be young explainers at the Weizmann Institutes Clore Garden of Science. To this end they study the physics underlying its exhibits in an after-school course. The ultimate goal is for the 'magmadim' to become the best possible explainers and be able to face all sorts of museum visitors. Along with learning how to instruct visitors, they must learn the physics behind the exhibits to give a full explanation of the exhibit and be able to answer any question that may arise. Our 5 year experience with the program shows that its self-selected participants not only study a lot of science, but also like it and learn how to explain the content to other people. This program, along with similar programs at the Bloomfield Science Museum and the Madatzim (young physics tutors) program of Ort, help in promoting the interest in science in general and physics in particular among school students. Various ways to expand the programs will also be discussed

  1. Linear Algebra Thoroughly Explained

    CERN Document Server

    Vujičić, Milan

    2008-01-01

    Linear Algebra Thoroughly Explained provides a comprehensive introduction to the subject suitable for adoption as a self-contained text for courses at undergraduate and postgraduate level. The clear and comprehensive presentation of the basic theory is illustrated throughout with an abundance of worked examples. The book is written for teachers and students of linear algebra at all levels and across mathematics and the applied sciences, particularly physics and engineering. It will also be an invaluable addition to research libraries as a comprehensive resource book for the subject.

  2. Explaining Disparities in Unemployment Dynamics

    OpenAIRE

    Karanassou, Marika; Snower, Dennis J.

    1993-01-01

    This paper attempts to explain disparities among the unemployment experiences of different OECD countries in terms of the `fragility' of the short-run unemployment equilibrium (the impact of labour market shocks on the short-run unemployment rate) and the lag structure of the employment determination, wage setting, and labour force participation decisions. The effects of this lag structure on unemployment dynamics are captured through two general measures of `unemployment persistence' (occurr...

  3. Meaningful Effect Sizes, Intraclass Correlations, and Proportions of Variance Explained by Covariates for Planning Two- and Three-Level Cluster Randomized Trials of Social and Behavioral Outcomes.

    Science.gov (United States)

    Dong, Nianbo; Reinke, Wendy M; Herman, Keith C; Bradshaw, Catherine P; Murray, Desiree W

    2016-09-30

    There is a need for greater guidance regarding design parameters and empirical benchmarks for social and behavioral outcomes to inform assumptions in the design and interpretation of cluster randomized trials (CRTs). We calculated the empirical reference values on critical research design parameters associated with statistical power for children's social and behavioral outcomes, including effect sizes, intraclass correlations (ICCs), and proportions of variance explained by a covariate at different levels (R 2 ). Children from kindergarten to Grade 5 in the samples from four large CRTs evaluating the effectiveness of two classroom- and two school-level preventive interventions. Teacher ratings of students' social and behavioral outcomes using the Teacher Observation of Classroom Adaptation-Checklist and the Social Competence Scale-Teacher. Two types of effect size benchmarks were calculated: (1) normative expectations for change and (2) policy-relevant demographic performance gaps. The ICCs and R 2 were calculated using two-level hierarchical linear modeling (HLM), where students are nested within schools, and three-level HLM, where students were nested within classrooms, and classrooms were nested within schools. Comprehensive tables of benchmarks and ICC values are provided to inform prevention researchers in interpreting the effect size of interventions and conduct power analyses for designing CRTs of children's social and behavioral outcomes. The discussion also provides a demonstration for how to use the parameter reference values provided in this article to calculate the sample size for two- and three-level CRTs designs. © The Author(s) 2016.

  4. Explaining wartime rape.

    Science.gov (United States)

    Gottschall, Jonathan

    2004-05-01

    In the years since the first reports of mass rapes in the Yugoslavian wars of secession and the genocidal massacres in Rwanda, feminist activists and scholars, human rights organizations, journalists, and social scientists have dedicated unprecedented efforts to document, explain, and seek solutions for the phenomenon of wartime rape. While contributors to this literature agree on much, there is no consensus on causal factors. This paper provides a brief overview of the literature on wartime rape in historical and ethnographical societies and a critical analysis of the four leading explanations for its root causes: the feminist theory, the cultural pathology theory, the strategic rape theory, and the biosocial theory. The paper concludes that the biosocial theory is the only one capable of bringing all the phenomena associated with wartime rape into a single explanatory context.

  5. Explaining moral religions.

    Science.gov (United States)

    Baumard, Nicolas; Boyer, Pascal

    2013-06-01

    Moralizing religions, unlike religions with morally indifferent gods or spirits, appeared only recently in some (but not all) large-scale human societies. A crucial feature of these new religions is their emphasis on proportionality (between deeds and supernatural rewards, between sins and penance, and in the formulation of the Golden Rule, according to which one should treat others as one would like others to treat oneself). Cognitive science models that account for many properties of religion can be extended to these religions. Recent models of evolved dispositions for fairness in cooperation suggest that proportionality-based morality is highly intuitive to human beings. The cultural success of moralizing movements, secular or religious, could be explained based on proportionality. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Bath and shower effects in the rat parotid gland explain increased relative risk of parotid gland dysfunction after intensity-modulated radiotherapy.

    Science.gov (United States)

    van Luijk, Peter; Faber, Hette; Schippers, Jacobus M; Brandenburg, Sytze; Langendijk, Johannes A; Meertens, Harm; Coppes, Robert P

    2009-07-15

    To assess in a rat model whether adding a subtolerance dose in a region adjacent to a high-dose irradiated subvolume of the parotid gland influences its response (bath-and-shower effect). Irradiation of the whole, cranial 50%, and/or the caudal 50% of the parotid glands of Wistar rats was performed using 150-MeV protons. To determine suitable (i.e., subtolerance) dose levels for a bath-dose, both whole parotid glands were irradiated with 5 to 25 Gy. Subsequently groups of Wistar rats received 30 Gy to the caudal 50% (shower) and 0 to 10 Gy to the cranial 50% (bath) of both parotid glands. Stimulated saliva flow rate (function) was measured before and up to 240 days after irradiation. Irradiation of both glands up to a dose of 10 Gy did not result in late loss of function and is thus regarded subtolerance. Addition of a dose bath of 1 to 10 Gy to a high-dose in the caudal 50% of the glands resulted in enhanced function loss. Similar to the spinal cord, the parotid gland demonstrates a bath and shower effect, which may explain the less-than-expected sparing of function after IMRT.

  7. Explaining gender segregation.

    Science.gov (United States)

    Blackburn, Robert M; Browne, Jude; Brooks, Bradley; Jarman, Jennifer

    2002-12-01

    Occupational gender segregation--the tendency for women and men to work in different occupations--is an important feature of all societies, and particularly the wealthy industrialized ones. To understand this segregation, and to explain its significance, we need to distinguish between vertical segregation entailing inequality and horizontal segregation representing difference without inequality, with overall segregation being the resultant of these components. Three major theoretical approaches to understanding occupational gender segregation are examined: human capital/rational choice, patriarchy, and preference theories. All are found to be inadequate; they tend to confuse overall segregation with its vertical component, and each entails a number of other faults. It is generally assumed or implied that greater empowerment of women would reduce gender segregation. This is the reverse of what actually happens; in countries where the degree of women's empowerment is greater, the level of gender segregation is also greater. An alternative theoretical approach based on processes of social reproduction is shown to be more useful.

  8. Explaining Synthesized Software

    Science.gov (United States)

    VanBaalen, Jeffrey; Robinson, Peter; Lowry, Michael; Pressburger, Thomas; Lau, Sonie (Technical Monitor)

    1998-01-01

    Motivated by NASA's need for high-assurance software, NASA Ames' Amphion project has developed a generic program generation system based on deductive synthesis. Amphion has a number of advantages, such as the ability to develop a new synthesis system simply by writing a declarative domain theory. However, as a practical matter, the validation of the domain theory for such a system is problematic because the link between generated programs and the domain theory is complex. As a result, when generated programs do not behave as expected, it is difficult to isolate the cause, whether it be an incorrect problem specification or an error in the domain theory. This paper describes a tool we are developing that provides formal traceability between specifications and generated code for deductive synthesis systems. It is based on extensive instrumentation of the refutation-based theorem prover used to synthesize programs. It takes augmented proof structures and abstracts them to provide explanations of the relation between a specification, a domain theory, and synthesized code. In generating these explanations, the tool exploits the structure of Amphion domain theories, so the end user is not confronted with the intricacies of raw proof traces. This tool is crucial for the validation of domain theories as well as being important in everyday use of the code synthesis system. It plays an important role in validation because when generated programs exhibit incorrect behavior, it provides the links that can be traced to identify errors in specifications or domain theory. It plays an important role in the everyday use of the synthesis system by explaining to users what parts of a specification or of the domain theory contribute to what pieces of a generated program. Comments are inserted into the synthesized code that document these explanations.

  9. Transient competitive complexation in biological kinetic isotope fractionation explains non-steady isotopic effects: Theory and application to denitrification in soils

    Energy Technology Data Exchange (ETDEWEB)

    Maggi, F.M.; Riley, W.J.

    2009-06-01

    The theoretical formulation of biological kinetic reactions in isotopic applications often assume first-order or Michaelis-Menten-Monod kinetics under the quasi-steady-state assumption to simplify the system kinetics. However, isotopic e ects have the same order of magnitude as the potential error introduced by these simpli cations. Both formulations lead to a constant fractionation factor which may yield incorrect estimations of the isotopic effect and a misleading interpretation of the isotopic signature of a reaction. We have analyzed the isotopic signature of denitri cation in biogeochemical soil systems by Menyailo and Hungate [2006], where high {sup 15}N{sub 2}O enrichment during N{sub 2}O production and inverse isotope fractionation during N{sub 2}O consumption could not be explained with first-order kinetics and the Rayleigh equation, or with the quasi-steady-state Michaelis-Menten-Monod kinetics. When the quasi-steady-state assumption was relaxed, transient Michaelis-Menten-Monod kinetics accurately reproduced the observations and aided in interpretation of experimental isotopic signatures. These results may imply a substantial revision in using the Rayleigh equation for interpretation of isotopic signatures and in modeling biological kinetic isotope fractionation with first-order kinetics or quasi-steady-state Michaelis-Menten-Monod kinetics.

  10. Explaining the effects of an intervention designed to promote evidence-based diabetes care: a theory-based process evaluation of a pragmatic cluster randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Kaner Eileen FS

    2008-11-01

    findings, thus offering an interpretation of the trial effects. This analytic approach demonstrates the potential of the TPB to explain trial effects in terms of different relationships between variables rather than differences in mean scores. This study illustrates the use of theory-based process evaluation to uncover processes underlying change in implementation trials.

  11. A sequential vesicle pool model with a single release sensor and a Ca(2+-dependent priming catalyst effectively explains Ca(2+-dependent properties of neurosecretion.

    Directory of Open Access Journals (Sweden)

    Alexander M Walter

    Full Text Available Neurotransmitter release depends on the fusion of secretory vesicles with the plasma membrane and the release of their contents. The final fusion step displays higher-order Ca(2+ dependence, but also upstream steps depend on Ca(2+. After deletion of the Ca(2+ sensor for fast release - synaptotagmin-1 - slower Ca(2+-dependent release components persist. These findings have provoked working models involving parallel releasable vesicle pools (Parallel Pool Models, PPM driven by alternative Ca(2+ sensors for release, but no slow release sensor acting on a parallel vesicle pool has been identified. We here propose a Sequential Pool Model (SPM, assuming a novel Ca(2+-dependent action: a Ca(2+-dependent catalyst that accelerates both forward and reverse priming reactions. While both models account for fast fusion from the Readily-Releasable Pool (RRP under control of synaptotagmin-1, the origins of slow release differ. In the SPM the slow release component is attributed to the Ca(2+-dependent refilling of the RRP from a Non-Releasable upstream Pool (NRP, whereas the PPM attributes slow release to a separate slowly-releasable vesicle pool. Using numerical integration we compared model predictions to data from mouse chromaffin cells. Like the PPM, the SPM explains biphasic release, Ca(2+-dependence and pool sizes in mouse chromaffin cells. In addition, the SPM accounts for the rapid recovery of the fast component after strong stimulation, where the PPM fails. The SPM also predicts the simultaneous changes in release rate and amplitude seen when mutating the SNARE-complex. Finally, it can account for the loss of fast- and the persistence of slow release in the synaptotagmin-1 knockout by assuming that the RRP is depleted, leading to slow and Ca(2+-dependent fusion from the NRP. We conclude that the elusive 'alternative Ca(2+ sensor' for slow release might be the upstream priming catalyst, and that a sequential model effectively explains Ca(2+-dependent

  12. Explaining Management Innovation Pervasiveness

    DEFF Research Database (Denmark)

    Harder, Mie

    on the behavioral theory of the firm, the determinants of firms’ adoption of pervasive management innovations are explored. I find that performance shortfalls have a direct positive effect on the pervasiveness of adopted innovations. Likewise, I find a direct effect of education level, richness of internal......Management innovation is the introduction of new management practices, processes, techniques or organizational structures that significantly alter the way the work of management is performed. This paper examines a particular characteristic of management innovation: i.e. pervasiveness. Based...

  13. Explaining frailty by lifestyle

    NARCIS (Netherlands)

    Gobbens, Robbert J J; van Assen, Marcel A L M

    2016-01-01

    Objective: To determine whether the effects of lifestyle factors on frailty can be adequately addressed by asking a single self-report question. Design: Cross-sectional study. Setting: A sample of Dutch citizens completed the web-based questionnaire "Seniorenbarometer". Participants: 610 persons

  14. Explaining through causal mechanisms

    NARCIS (Netherlands)

    Biesbroek, Robbert; Dupuis, Johann; Wellstead, Adam

    2017-01-01

    This paper synthesizes and builds on recent critiques of the resilience literature; namely that the field has largely been unsuccessful in capturing the complexity of governance processes, in particular cause–effects relationships. We demonstrate that absence of a causal model is reflected in the

  15. The ‘cutting away’ of potential secondary electron tracks explains the effects of beam size and detector wall density in small-field photon dosimetry

    Science.gov (United States)

    Khee Looe, Hui; Delfs, Björn; Poppinga, Daniela; Jiang, Ping; Harder, Dietrich; Poppe, Björn

    2018-01-01

    The well-known field-size dependent overresponse in small-field photon-beam dosimetry of solid-state detectors equipped with very thin sensitive volumes, such as the PTW microDiamond, cannot be caused by the photon and electron interactions within these sensitive layers because they are only a few micrometers thick. The alternative explanation is that their overresponse is caused by the combination of two effects, the modification of the secondary electron fluence profile (i) by a field size too small to warrant lateral secondary electron equilibrium and (ii) by the density-dependent electron ranges in the structural detector materials placed in front of or backing the sensitive layer. The present study aims at the numerical demonstration and visualization of this combined mechanism. The lateral fluence profiles of the secondary electrons hitting a 1 µm thick scoring layer were Monte-Carlo simulated by modelling their generation and transport in the upstream or downstream adjacent layers of thickness 0.6 mm and densities from 0.0012 to 3 g cm‑3, whose atomic composition was constantly kept water-like. The scoring layer/adjacent layer sandwich was placed in an infinite water phantom irradiated by circular 60Co, 6 MV and 15 MV photon beams with diameters from 3 to 40 mm. The interpretation starts from the ideal case of lateral secondary electron equilibrium, where the Fano theorem excludes any density effect. If the field size is then reduced, electron tracks potentially originating from source points outside the field border will then be numerically ‘cut away’. This geometrical effect reduces the secondary electron fluence at the field center, but the magnitude of this reduction also varies with the density-dependent electron ranges in the adjacent layers. This combined mechanism, which strongly depends on the photon spectrum, explains the field size and material density effect on the response of detectors with very thin sensitive layers used in small

  16. Explaining Management Innovation Pervasiveness

    OpenAIRE

    Harder, Mie

    2011-01-01

    Management innovation is the introduction of new management practices, processes, techniques or organizational structures that significantly alter the way the work of management is performed. This paper examines a particular characteristic of management innovation: i.e. pervasiveness. Based on the behavioral theory of the firm, the determinants of firms’ adoption of pervasive management innovations are explored. I find that performance shortfalls have a direct positive effect on t...

  17. A synergistic antiproliferation effect of curcumin and docosahexaenoic acid in SK-BR-3 breast cancer cells: unique signaling not explained by the effects of either compound alone

    Directory of Open Access Journals (Sweden)

    Jo Davisson V

    2011-04-01

    Full Text Available Abstract Background Breast cancer is a collection of diseases in which molecular phenotypes can act as both indicators and mediators of therapeutic strategy. Therefore, candidate therapeutics must be assessed in the context of multiple cell lines with known molecular phenotypes. Docosahexaenoic acid (DHA and curcumin (CCM are dietary compounds known to antagonize breast cancer cell proliferation. We report that these compounds in combination exert a variable antiproliferative effect across multiple breast cell lines, which is synergistic in SK-BR-3 cells and triggers cell signaling events not predicted by the activity of either compound alone. Methods Dose response curves for CCM and DHA were generated for five breast cell lines. Effects of the DHA+ CCM combination on cell proliferation were evaluated using varying concentrations, at a fixed ratio, of CCM and DHA based on their individual ED50. Detection of synergy was performed using nonlinear regression of a sigmoid dose response model and Combination Index approaches. Cell molecular network responses were investigated through whole genome microarray analysis of transcript level changes. Gene expression results were validated by RT-PCR, and western blot analysis was performed for potential signaling mediators. Cellular curcumin uptake, with and without DHA, was analyzed via flow cytometry and HPLC. Results CCM+DHA had an antiproliferative effect in SK-BR-3, MDA-MB-231, MDA-MB-361, MCF7 and MCF10AT cells. The effect was synergistic for SK-BR-3 (ER- PR- Her2+ relative to the two compounds individually. A whole genome microarray approach was used to investigate changes in gene expression for the synergistic effects of CCM+DHA in SK-BR-3 cells lines. CCM+DHA triggered transcript-level responses, in disease-relevant functional categories, that were largely non-overlapping with changes caused by CCM or DHA individually. Genes involved in cell cycle arrest, apoptosis, inhibition of metastasis, and

  18. A synergistic antiproliferation effect of curcumin and docosahexaenoic acid in SK-BR-3 breast cancer cells: unique signaling not explained by the effects of either compound alone

    International Nuclear Information System (INIS)

    Altenburg, Jeffrey D; Bieberich, Andrew A; Terry, Colin; Harvey, Kevin A; VanHorn, Justin F; Xu, Zhidong; Jo Davisson, V; Siddiqui, Rafat A

    2011-01-01

    Breast cancer is a collection of diseases in which molecular phenotypes can act as both indicators and mediators of therapeutic strategy. Therefore, candidate therapeutics must be assessed in the context of multiple cell lines with known molecular phenotypes. Docosahexaenoic acid (DHA) and curcumin (CCM) are dietary compounds known to antagonize breast cancer cell proliferation. We report that these compounds in combination exert a variable antiproliferative effect across multiple breast cell lines, which is synergistic in SK-BR-3 cells and triggers cell signaling events not predicted by the activity of either compound alone. Dose response curves for CCM and DHA were generated for five breast cell lines. Effects of the DHA+ CCM combination on cell proliferation were evaluated using varying concentrations, at a fixed ratio, of CCM and DHA based on their individual ED 50 . Detection of synergy was performed using nonlinear regression of a sigmoid dose response model and Combination Index approaches. Cell molecular network responses were investigated through whole genome microarray analysis of transcript level changes. Gene expression results were validated by RT-PCR, and western blot analysis was performed for potential signaling mediators. Cellular curcumin uptake, with and without DHA, was analyzed via flow cytometry and HPLC. CCM+DHA had an antiproliferative effect in SK-BR-3, MDA-MB-231, MDA-MB-361, MCF7 and MCF10AT cells. The effect was synergistic for SK-BR-3 (ER - PR - Her2 + ) relative to the two compounds individually. A whole genome microarray approach was used to investigate changes in gene expression for the synergistic effects of CCM+DHA in SK-BR-3 cells lines. CCM+DHA triggered transcript-level responses, in disease-relevant functional categories, that were largely non-overlapping with changes caused by CCM or DHA individually. Genes involved in cell cycle arrest, apoptosis, inhibition of metastasis, and cell adhesion were upregulated, whereas genes

  19. Explaining the host-finding behavior of blood-sucking insects: computerized simulation of the effects of habitat geometry on tsetse fly movement.

    Directory of Open Access Journals (Sweden)

    Glyn A Vale

    2014-06-01

    Full Text Available BACKGROUND: Male and female tsetse flies feed exclusively on vertebrate blood. While doing so they can transmit the diseases of sleeping sickness in humans and nagana in domestic stock. Knowledge of the host-orientated behavior of tsetse is important in designing bait methods of sampling and controlling the flies, and in understanding the epidemiology of the diseases. For this we must explain several puzzling distinctions in the behavior of the different sexes and species of tsetse. For example, why is it that the species occupying savannahs, unlike those of riverine habitats, appear strongly responsive to odor, rely mainly on large hosts, are repelled by humans, and are often shy of alighting on baits? METHODOLOGY/PRINCIPAL FINDINGS: A deterministic model that simulated fly mobility and host-finding success suggested that the behavioral distinctions between riverine, savannah and forest tsetse are due largely to habitat size and shape, and the extent to which dense bushes limit occupiable space within the habitats. These factors seemed effective primarily because they affect the daily displacement of tsetse, reducing it by up to ∼70%. Sex differences in behavior are explicable by females being larger and more mobile than males. CONCLUSION/SIGNIFICANCE: Habitat geometry and fly size provide a framework that can unify much of the behavior of all sexes and species of tsetse everywhere. The general expectation is that relatively immobile insects in restricted habitats tend to be less responsive to host odors and more catholic in their diet. This has profound implications for the optimization of bait technology for tsetse, mosquitoes, black flies and tabanids, and for the epidemiology of the diseases they transmit.

  20. Explaining the host-finding behavior of blood-sucking insects: computerized simulation of the effects of habitat geometry on tsetse fly movement.

    Science.gov (United States)

    Vale, Glyn A; Hargrove, John W; Solano, Philippe; Courtin, Fabrice; Rayaisse, Jean-Baptiste; Lehane, Michael J; Esterhuizen, Johan; Tirados, Inaki; Torr, Stephen J

    2014-06-01

    Male and female tsetse flies feed exclusively on vertebrate blood. While doing so they can transmit the diseases of sleeping sickness in humans and nagana in domestic stock. Knowledge of the host-orientated behavior of tsetse is important in designing bait methods of sampling and controlling the flies, and in understanding the epidemiology of the diseases. For this we must explain several puzzling distinctions in the behavior of the different sexes and species of tsetse. For example, why is it that the species occupying savannahs, unlike those of riverine habitats, appear strongly responsive to odor, rely mainly on large hosts, are repelled by humans, and are often shy of alighting on baits? A deterministic model that simulated fly mobility and host-finding success suggested that the behavioral distinctions between riverine, savannah and forest tsetse are due largely to habitat size and shape, and the extent to which dense bushes limit occupiable space within the habitats. These factors seemed effective primarily because they affect the daily displacement of tsetse, reducing it by up to ∼70%. Sex differences in behavior are explicable by females being larger and more mobile than males. Habitat geometry and fly size provide a framework that can unify much of the behavior of all sexes and species of tsetse everywhere. The general expectation is that relatively immobile insects in restricted habitats tend to be less responsive to host odors and more catholic in their diet. This has profound implications for the optimization of bait technology for tsetse, mosquitoes, black flies and tabanids, and for the epidemiology of the diseases they transmit.

  1. The Protective Effect of Low-Dose Aspirin against Colorectal Cancer Is Unlikely Explained by Selection Bias: Results from Three Different Study Designs in Clinical Practice.

    Directory of Open Access Journals (Sweden)

    Lucía Cea Soriano

    Full Text Available We conducted three differently designed nested case-control studies to evaluate whether the protective effect of low-dose aspirin against colorectal cancer (CRC is explained by selection bias.Using a large validated UK primary care database, we followed different cohorts of patients, who varied in their demographic and clinical characteristics, to identify first ever cases of CRC. In Studies 1 and 2, two cohorts were followed, i new users of low-dose aspirin at start of follow-up (N = 170,336 in Study 1, N = 171,527 in Study 2 and either ii non-users of low-dose aspirin (Study 1, N = 170,336 or new users of paracetamol (Study 2, N = 149,597 at start of follow-up. In Study 3 a single cohort of individuals näive to low-dose aspirin at the start of observation was followed. Controls were selected using incidence sampling and logistic regression used to obtain an unbiased estimate of the incidence rate ratio (RR with 95% confidence intervals (CIs. Low-dose aspirin exposure was analyzed 'as-treated' before the index date (CRC date for cases, random date for controls.In the three studies, median (maximum follow-up was 5.1 (12, 5.8 (12 and 7.5 (13 years, respectively. 3033 incident CRC cases were identified in Study 1, 3174 in Study 2, and 12,333 in Study 3. Current use of low-dose aspirin was associated with a significantly reduced risk of 34%, 29% and 31% in the three studies, respectively; corresponding RRs (95% CIs were 0.66 (0.60-0.73, 0.71 (0.63-0.80 and 0.69 (0.64-0.74. In each study, significantly reduced risks of CRC were seen when low-dose aspirin was used for primary or secondary cardiovascular disease prevention, in both sexes, and across all age groups evaluated.Low-dose aspirin is associated with a significantly reduced risk of CRC. The consistency of our findings across different studies makes selection bias an unlikely explanation.

  2. Explaining the host-finding behavior of blood-sucking insects : computerized simulation of the effects of habitat geometry on tsetse fly movement

    OpenAIRE

    Vale, G. A.; Hargrove, J. W.; Solano, Philippe; Courtin, Fabrice; Rayaisse, J. B.; Lehane, M. J.; Esterhuizen, J.; Tirados, I.; Torr, S. J.

    2014-01-01

    Background\\ud \\ud Male and female tsetse flies feed exclusively on vertebrate blood. While doing so they can transmit the\\ud diseases of sleeping sickness in humans and nagana in domestic stock. Knowledge of the host-orientated behavior of tsetse is important in designing bait methods of sampling and controlling the flies, and in understanding the epidemiology of the diseases. For this we must explain several puzzling distinctions in the behavior of the different sexes and species of tsetse. ...

  3. A test of rivaling approaches to explain news effects: A multi-wave panel study of agenda setting, social and economic conditions, the tone of the news, and horse race news

    NARCIS (Netherlands)

    Kleinnijenhuis, J.; van Hoof, A.M.J.; Oegema, D.; de Ridder, J.A.

    2007-01-01

    Different "paradigmatic" approaches to explain news effects on voting may supplement each other, because their starting points are based on different news types in political campaign news: news on issue positions of parties, news on real-world developments, news on support or criticism for parties,

  4. Investigating the role of male advantage and female disadvantage in explaining the discrimination effect of the gender pay gap in the Cameroon labor market. Oaxaca-Ransom decomposition approach

    Directory of Open Access Journals (Sweden)

    Dickson Thomas NDAMSA

    2015-05-01

    Full Text Available The paper assesses the sources of gender-based wage differentials and investigates the relative importance of the endowment effect, female disadvantage and male advantage in explaining gender-based wage differentials in the Cameroon labor market. Use is made of the Ordinary Least Square technique and the Oaxaca-Ransom decomposition. Oaxaca-Ransom decomposition results show that primary education, secondary education, tertiary education and professional training are sources of the gender pay gap. Our results also underline the importance of working experience, formal sector employment and urban residency in explaining wage differentials between male and female workers in the Cameroon labour market. Our findings reveal that education human capital explains a greater portion of the endowment effect and contributes little to the discrimination effect. Essentially, we observe that the discrimination effect has a worsening effect on the gender pay gap compared to the mitigating role of the endowment effect. Again, our results show that a greater part of the discrimination effect of the gender pay gap is attributed to female disadvantage in the Cameroon labor market.

  5. Your Radiologist Explains CT Colonography

    Medline Plus

    Full Text Available ... Radiology and You Take our survey Sponsored by Image/Video Gallery Your Radiologist Explains CT Colonography (Virtual ... to allow for inflation with air while CT images are being taken. If you’re scheduled for ...

  6. Your Radiologist Explains Nuclear Medicine

    Medline Plus

    Full Text Available ... Radiology and You Take our survey Sponsored by Image/Video Gallery Your Radiologist Explains Nuclear Medicine Transcript ... by a special camera and computer to create images of the inside of your body. If you’ ...

  7. Your Radiologist Explains Nuclear Medicine

    Medline Plus

    Full Text Available ... Abdominal Ultrasound Video: Pelvic Ultrasound Medical Imaging Costs Radiology and You Take our survey Sponsored by Image/ ... Your Radiologist Explains Nuclear Medicine Transcript Welcome to Radiology Info dot org Hello! I’m Dr. Ramji ...

  8. Your Radiologist Explains CT Colonography

    Medline Plus

    Full Text Available ... Abdominal Ultrasound Video: Pelvic Ultrasound Medical Imaging Costs Radiology and You Take our survey Sponsored by Image/ ... Explains CT Colonography (Virtual colonoscopy) Transcript Welcome to Radiology Info dot org! Hi, I’m Dr. Elliot ...

  9. Your Radiologist Explains CT Colonography

    Medline Plus

    Full Text Available ... and You Take our survey Sponsored by Image/Video Gallery Your Radiologist Explains CT Colonography (Virtual colonoscopy) ... Carotid Intima-Media Thickness Test Medical Imaging Costs Video: Abdominal Ultrasound Video: Pelvic Ultrasound Radiology and You ...

  10. Your Radiologist Explains Nuclear Medicine

    Medline Plus

    Full Text Available ... and You Take our survey Sponsored by Image/Video Gallery Your Radiologist Explains Nuclear Medicine Transcript Welcome ... Carotid Intima-Media Thickness Test Medical Imaging Costs Video: Abdominal Ultrasound Video: Pelvic Ultrasound Radiology and You ...

  11. Explaining variation in nascent entrepreneurship

    NARCIS (Netherlands)

    A.J. van Stel (André); A.R.M. Wennekers (Sander); P. Reynolds (Paul); A.R. Thurik (Roy)

    2004-01-01

    textabstractThis paper aims at explaining cross-country variation in nascent entrepreneurship. Regression analysis is applied using various explanatory variables derived from three different approaches. We make use of the Global Entrepreneurship Monitor database, including nascent entrepreneurship

  12. Your Radiologist Explains Nuclear Medicine

    Medline Plus

    Full Text Available ... Sponsored by Image/Video Gallery Your Radiologist Explains Nuclear Medicine Transcript Welcome to Radiology Info dot org ... I’d like to talk to you about nuclear medicine. Nuclear medicine offers the potential to identify ...

  13. Your Radiologist Explains Nuclear Medicine

    Medline Plus

    Full Text Available ... by Image/Video Gallery Your Radiologist Explains Nuclear Medicine Transcript Welcome to Radiology Info dot org Hello! ... d like to talk to you about nuclear medicine. Nuclear medicine offers the potential to identify disease ...

  14. Your Radiologist Explains Nuclear Medicine

    Science.gov (United States)

    ... Sponsored by Image/Video Gallery Your Radiologist Explains Nuclear Medicine Transcript Welcome to Radiology Info dot org Hello! ... I’d like to talk to you about nuclear medicine. Nuclear medicine offers the potential to identify disease ...

  15. The Safer Delivery of Surgical Services Program (S3): Explaining Its Differential Effectiveness and Exploring Implications for Improving Quality in Complex Systems.

    Science.gov (United States)

    Flynn, Lorna C; McCulloch, Peter G; Morgan, Lauren J; Robertson, Eleanor R; New, Steve J; Stedman, Francesca E; Martin, Graham P

    2016-12-01

    To analyze the challenges encountered during surgical quality improvement interventions, and explain the relative success of different intervention strategies. Understanding why and how interventions work is vital for developing improvement science. The S3 Program of studies tested whether combining interventions addressing culture and system was more likely to result in improvement than either approach alone. Quantitative results supported this theory. This qualitative study investigates why this happened, what aspects of the interventions and their implementation most affected improvement, and the implications for similar programs. Semistructured interviews were conducted with hospital staff (23) and research team members (11) involved in S3 studies. Analysis was based on the constant comparative method, with coding conducted concurrently with data collection. Themes were identified and developed in relation to the program theory behind S3. The superior performance of combined intervention over single intervention arms appeared related to greater awareness and ability to act, supporting the S3 hypothesis. However, we also noted unforeseen differences in implementation that seemed to amplify this difference. The greater ambition and more sophisticated approach in combined intervention arms resulted in requests for more intensive expert support, which seemed crucial in their success. The contextual challenges encountered have potential implications for the replicability and sustainability of the approach. Our findings support the S3 hypothesis, triangulating with quantitative results and providing an explanatory account of the causal relationship between interventions and outcomes. They also highlight the importance of implementation strategies, and of factors outside the control of program designers.

  16. An improved oxygen diffusion model to explain the effect of low-temperature baking on high field losses in niobium superconducting cavities

    Energy Technology Data Exchange (ETDEWEB)

    Ciovati, Gianluigi

    2006-07-01

    Radio-frequency (RF) superconducting cavities made of high purity niobium are widely used to accelerate charged particle beams in particle accelerators. The major limitation to achieve RF field values approaching the theoretical limit for niobium is represented by ''anomalous'' losses which degrade the quality factor of the cavities starting at peak surface magnetic fields of about 100 mT, in absence of field emission. These high field losses are often referred to as ''Q-drop''. It has been observed that the Q-drop is drastically reduced by baking the cavities at 120 C for about 48 h under ultrahigh vacuum. An improved oxygen diffusion model for the niobium-oxide system is proposed to explain the benefit of the low-temperature baking on the Q-drop in niobium superconducting rf cavities. The model shows that baking at 120 C for 48 h allows oxygen to diffuse away from the surface, and therefore increasing the lower critical field towards the value for pure niobium.

  17. Hd86 mRNA expression profile in Hyalomma scupense life stages, could it contribute to explain anti-tick vaccine effect discrepancy between adult and immature instars?

    Science.gov (United States)

    Ben Said, Mourad; Galaï, Yousr; Ben Ahmed, Melika; Gharbi, Mohamed; de la Fuente, José; Jedidi, Mohamed; Darghouth, Mohamed Aziz

    2013-11-15

    Bm86 midgut protein has been used in order to control ticks of the Hyalomma genus. Previous studies demonstrated the inefficacity of this antigen in the control of Hyalomma scupense, whereas recombinant Hd86 antigen, the Bm86 ortholog in H. scupense produced in Pichia pastoris, was protective against larval H. scupense tick stage infestations but ineffective in the control of the adult stage. One possible explanation for this result is the variation in Hd86 expression levels between these two developmental stages. To test this hypothesis, Hd86 mRNA levels were characterized in H. scupense developmental stages. The expression profile of Hd86 demonstrated a significant variation between tick life stages and showed a significant reduction in the number of transcripts during feeding and, particularly after molting to adults. The most interesting result was noted after molting of engorged nymphs in unfed adults where the expression levels decreased significantly by 12.78 (10.77-17.39) (pstages might explain, in part, the discrepancy of the Hd86 vaccine efficacy against these two life stages of H. scupense. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Explaining Method Effects Associated with Negatively Worded Items in Trait and State Global and Domain-Specific Self-Esteem Scales

    Science.gov (United States)

    Tomas, Jose M.; Oliver, Amparo; Galiana, Laura; Sancho, Patricia; Lila, Marisol

    2013-01-01

    Several investigators have interpreted method effects associated with negatively worded items in a substantive way. This research extends those studies in different ways: (a) it establishes the presence of methods effects in further populations and particular scales, and (b) it examines the possible relations between a method factor associated…

  19. Mining and Explaining Relationships in Wikipedia

    Science.gov (United States)

    Zhang, Xinpeng; Asano, Yasuhito; Yoshikawa, Masatoshi

    Mining and explaining relationships between concepts are challenging tasks in the field of knowledge search. We propose a new approach for the tasks using disjoint paths formed by links in Wikipedia. Disjoint paths are easy to understand and do not contain redundant information. To achieve this approach, we propose a naive method, as well as a generalized flow based method, and a technique for mining more disjoint paths using the generalized flow based method. We also apply the approach to classification of relationships. Our experiments reveal that the generalized flow based method can mine many disjoint paths important for understanding a relationship, and the classification is effective for explaining relationships.

  20. Can Marxism Explain America's Racism?

    Science.gov (United States)

    Willhelm, Sidney M.

    1980-01-01

    The Marxist interpretation of the Black experience in America has always had difficulty explaining various noneconomic aspects of racism. A perspective is needed that can blend racism as a variable in relationship with economic variables. To reach this perspective, the labor process within capitalism must be more fully understood. (Author/GC)

  1. Journalism and Explaining News Content

    NARCIS (Netherlands)

    Albæk, E.; Skovsgaard, M.; de Vreese, C.H.; Nussbaum, J.F.

    Three models are presented to explain variation in news content. In the first model the explanation is based on the individual journalist, in the second model on the professional journalist, and in the third model on the organized journalist. The individual journalist model focuses on how the

  2. Does market competition explain fairness?

    Science.gov (United States)

    Descioli, Peter

    2013-02-01

    The target article by Baumard et al. uses their previous model of bargaining with outside options to explain fairness and other features of human sociality. This theory implies that fairness judgments are determined by supply and demand but humans often perceive prices (divisions of surplus) in competitive markets to be unfair.

  3. Your Radiologist Explains Nuclear Medicine

    Medline Plus

    Full Text Available ... Sponsored by Image/Video Gallery Your Radiologist Explains Nuclear Medicine Transcript Welcome to Radiology Info dot org Hello! ... I’d like to talk to you about nuclear medicine. Nuclear medicine offers the potential to identify disease ...

  4. At the centennial of Michaelis and Menten, competing Michaelis-Menten steps explain effect of GLP-1 on blood-brain transfer and metabolism of glucose

    DEFF Research Database (Denmark)

    Jensen, Michael Gejl; Rungby, Jørgen; Brock, Birgitte

    2014-01-01

    and Maud Menten described the steady-state enzyme kinetics that still apply to the multiple receptors, transporters and enzymes that define the biochemical reactions of the brain, including the glucose-dependent impact of GLP-1 on blood-brain glucose transfer and metabolism. This MiniReview examines......Glucagon-like peptide-1 (GLP-1) is a potent insulinotropic incretin hormone with pancreatic and extrapancreatic effects. Studies reveal significant effects in regions of brain tissue that regulate appetite and satiety. The effects cause that mimetics of GLP-1 serves as treatment of type 2 diabetes...... the potential of GLP-1 as a molecule of interest to the understanding of brain energy metabolism and notes the impact on brain metabolism related to appetite and satiety regulation, stroke and neurodegenerative disorders, among others. These effects can be understood only by reference to the original...

  5. Explaining the effects of a point-of-purchase nutrition-information intervention in university canteens: a structural equation modelling analysis

    Directory of Open Access Journals (Sweden)

    Hoefkens Christine

    2012-09-01

    Full Text Available Abstract Background The importance of canteen meals in the diet of many university students makes the provision of simple point-of-purchase (POP nutrition information in university canteens a potentially effective way to promote healthier diets in an important group of young adults. However, modifications to environments such as the posting of POP nutrition information in canteens may not cause an immediate change in meal choices and nutrient intakes. The present study aimed at understanding the process by which the POP nutrition information achieved its effects on the meal choice and energy intake, and whether the information was more effective in changing the meal choice of subgroups of university canteen customers. Methods The POP nutrition-information intervention used a one-group pretest-posttest design. A sample of 224 customers of two university canteens completed the baseline and 6-months follow-up surveys. A multi-group structural equation modelling analysis was used to test mediation effects of individual difference variables (liking, understanding and use of the information, subjective knowledge and attitude on the energy intake from canteen meals, moderated by the objective nutrition knowledge and motivation to change diet. Results Significant relations were identified between liking of the information and its use on one hand and a positive effect in attitude towards healthy canteen meals on the other hand. Motivation to change diet and sufficient objective nutrition knowledge were required to maintain a recommended energy intake from canteen meals or to lead to a decrease in energy intake. Participants with greater objective nutrition knowledge had a greater understanding of the POP nutrition information which also resulted in a more effective use of the information. Conclusions The results suggest that nutrition-information interventions may be more effective when using nutrition information that is generally liked by the target

  6. BATH AND SHOWER EFFECTS IN THE RAT PAROTID GLAND EXPLAIN INCREASED RELATIVE RISK OF PAROTID GLAND DYSFUNCTION AFTER INTENSITY-MODULATED RADIOTHERAPY

    NARCIS (Netherlands)

    van Luijk, Peter; Faber, Hette; Schippers, Jacobus M.; Brandenburg, Sytze; Langendijk, Johannes A.; Meertens, Harm; Coppes, Robert P.

    2009-01-01

    Purpose: To assess in a rat model whether adding a subtolerance dose in a region adjacent to a high-dose irradiated subvolume of the parotid gland influences its response (bath-and-shower effect). Methods and Materials: Irradiation of the whole, cranial 50%, and/or the caudal 50% of the parotid

  7. Can bootstrapping explain concept learning?

    Science.gov (United States)

    Beck, Jacob

    2017-01-01

    Susan Carey's account of Quinean bootstrapping has been heavily criticized. While it purports to explain how important new concepts are learned, many commentators complain that it is unclear just what bootstrapping is supposed to be or how it is supposed to work. Others allege that bootstrapping falls prey to the circularity challenge: it cannot explain how new concepts are learned without presupposing that learners already have those very concepts. Drawing on discussions of concept learning from the philosophical literature, this article develops a detailed interpretation of bootstrapping that can answer the circularity challenge. The key to this interpretation is the recognition of computational constraints, both internal and external to the mind, which can endow empty symbols with new conceptual roles and thus new contents. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Explaining the effects of two different strategies for promoting hand hygiene in hospital nurses: a process evaluation alongside a cluster randomised controlled trial

    Science.gov (United States)

    2013-01-01

    Background There is only limited understanding of why hand hygiene improvement strategies are successful or fail. It is therefore important to look inside the ‘black box’ of such strategies, to ascertain which components of a strategy work well or less well. This study examined which components of two hand hygiene improvement strategies were associated with increased nurses’ hand hygiene compliance. Methods A process evaluation of a cluster randomised controlled trial was conducted in which part of the nursing wards of three hospitals in the Netherlands received a state-of-the-art strategy, including education, reminders, feedback, and optimising materials and facilities; another part received a team and leaders-directed strategy that included all elements of the state-of-the-art strategy, supplemented with activities aimed at the social and enhancing leadership. This process evaluation used four sets of measures: effects on nurses’ hand hygiene compliance, adherence to the improvement strategies, contextual factors, and nurses’ experiences with strategy components. Analyses of variance and multiple regression analyses were used to explore changes in nurses’ hand hygiene compliance and thereby better understand trial effects. Results Both strategies were performed with good adherence to protocol. Two contextual factors were associated with changes in hand hygiene compliance: a hospital effect in long term (p evaluation to uncover mechanisms underlying change in hand hygiene improvement strategies. Our study results demonstrate the added value of specific aspects of social influence and leadership in hand hygiene improvement strategies, thus offering an interpretation of the trial effects. Trial registration The study is registered in ClinicalTrials.gov, dossier number: NCT00548015. PMID:23566429

  9. Fluorine Gauche Effect Explained by Electrostatic Polarization Instead of Hyperconjugation: An Interacting Quantum Atoms (IQA) and Relative Energy Gradient (REG) Study.

    Science.gov (United States)

    Thacker, Joseph C R; Popelier, Paul L A

    2018-02-08

    We present an interacting quantum atoms (IQA) study of the gauche effect by comparing 1,2-difluoroethane, 1,2-dichloroethane, and three conformers of 1,2,3,4,5,6-hexafluorocyclohexane. In the 1,2-difluoroethane, the gauche effect is observed in that the gauche conformation is more stable than the anti, whereas in 1,2-dichloroethane the opposite is true. The analysis performed here is exhaustive and unbiased thanks to using the recently introduced relative energy gradient (REG) method [ Thacker , J. C. R. ; Popelier , P. L. A. Theor. Chem. Acc . 2017 , 136 , 86 ], as implemented in the in-house program ANANKE. We challenge the common explanation that hyperconjugation is responsible for the gauche stability in 1,2-difluoroethane and instead present electrostatics as the cause of gauche stability. Our explanation of the gauche effect is also is seen in other molecules displaying local gauche conformations, such as the recently synthesized "all-cis" hexafluorocyclohexane and its conformers where all the fluorine atoms are in the equatorial positions. Using our extension of the traditional IQA methodology that allows for the partitioning of electrostatic terms into polarization and charge transfer, we propose that the cause of gauche stability is 1,3 C···F electrostatic polarization interactions. In other words, if a number of fluorine atoms are aligned, then the stability due to polarization of nearby carbon atoms is increased.

  10. A comparative study of APLI and APCI in IMS at atmospheric pressure to reveal and explain peak broadening effects by the use of APLI.

    Science.gov (United States)

    Ihlenborg, Marvin; Raupers, Björn; Gunzer, Frank; Grotemeyer, Jürgen

    2015-11-21

    The details of the ionization mechanism in atmospheric pressure are still not completely known. In order to obtain further insight into the occurring processes in atmospheric pressure laser ionization (APLI) a comparative study of atmospheric pressure chemical ionization (APCI) and APLI is presented in this paper. This study is carried out using similar experimental condition at atmospheric pressure employing a commercial ion mobility spectrometer (IMS). Two different peak broadening mechanisms can then be assigned, one related to a range of different species generated and detected, and furthermore for the first time a power broadening effect on the signals can be identified.

  11. Effects of the 6th September 2002 earthquake: damage amplification in the south-eastern sector of Palermo explained by GIS technology

    Directory of Open Access Journals (Sweden)

    A. Zuccarello

    2003-06-01

    Full Text Available During the 6th September 2002 earthquake the highest damage level in Palermo was observed in the SE sector. This is a recent urbanization area where reinforced concrete structures predominate. A detailed analysis of soil properties in Palermo was carried out by City-GIS to investigate a possible role of nearsurface geology on earthquake effects. City-GIS is a tool dedicated to natural hazard evaluation in urban areas. The availability of high density of well log data (stratigraphic and geotechnical allowed a realistic modeling of surface geology and physical-mechanical properties that control the seismic response. In wide zones of the above mentioned sector of Palermo, outcropping terrains are composed of thin calcarenite layers, lying above remarkably thick siltyclayey sands that overlay the Numidian Flysch, commonly considered the bedrock of Quaternary sediments. Since silty-clayey sands feature greater deformability properties (Young's modulus and smaller resistance properties (undrained cohesion and shear resistance angle than Numidian Flysch, these zones of the SE sector exhibit high values of the acoustic impedance contrast. Moreover, a quite wide portion of the study area, crossed by the Oreto River, is characterized by very thick alluvial deposits. Here, the significant lateral variations of the lithostratigraphic geometry may be an additional cause of strong site effects.

  12. Ca2+ improves organization of single-stranded DNA bases in human Rad51 filament, explaining stimulatory effect on gene recombination.

    KAUST Repository

    Fornander, Louise H

    2012-02-22

    Human RAD51 protein (HsRad51) catalyses the DNA strand exchange reaction for homologous recombination. To clarify the molecular mechanism of the reaction in vitro being more effective in the presence of Ca(2+) than of Mg(2+), we have investigated the effect of these ions on the structure of HsRad51 filament complexes with single- and double-stranded DNA, the reaction intermediates. Flow linear dichroism spectroscopy shows that the two ionic conditions induce significantly different structures in the HsRad51/single-stranded DNA complex, while the HsRad51/double-stranded DNA complex does not demonstrate this ionic dependence. In the HsRad51/single-stranded DNA filament, the primary intermediate of the strand exchange reaction, ATP/Ca(2+) induces an ordered conformation of DNA, with preferentially perpendicular orientation of nucleobases relative to the filament axis, while the presence of ATP/Mg(2+), ADP/Mg(2+) or ADP/Ca(2+) does not. A high strand exchange activity is observed for the filament formed with ATP/Ca(2+), whereas the other filaments exhibit lower activity. Molecular modelling suggests that the structural variation is caused by the divalent cation interfering with the L2 loop close to the DNA-binding site. It is proposed that the larger Ca(2+) stabilizes the loop conformation and thereby the protein-DNA interaction. A tight binding of DNA, with bases perpendicularly oriented, could facilitate strand exchange.

  13. The Effect of a Laboratory Approach Based on Predict-Observation-Explain (POE Strategy on the Development of Students’ Science Process Skills and Views about Nature of Science

    Directory of Open Access Journals (Sweden)

    Kadir Bilen

    2012-06-01

    Full Text Available The purpose of this study was to investigate the effects of a laboratory instruction prepared based on “Predict-Observation-Explain” (POE strategy compared to a verification laboratory approach on the development of pre-service science teachers’ science skill processes and their views of nature of sceince in a general biology laboratory course. The participants of this study consisted of 122 pre-service teachers who took the General Biology Laboratory at the department of science education at Pamukkale University during the fall semester of 2007-2008 academic year. Data was collected through Science Process Skills Test (SPST and Nature of Science Questionnaire. Results indicated that there was a statistically significant difference between the verification laboratory approach and the laboratory approach based on the POE strategy on the development of students’ science process skills [F=10.41, p

  14. Pathways of Change Explaining the Effect of Smoke-Free Legislation on Smoking Cessation in the Netherlands. An Application of the International Tobacco Control Conceptual Model

    Science.gov (United States)

    de Vries, Hein; Fong, Geoffrey T.; Candel, Math J. J. M.; Thrasher, James F.; van den Putte, Bas; Thompson, Mary E.; Cummings, K. Michael; Willemsen, Marc C.

    2012-01-01

    Introduction: This study aims to test the pathways of change from individual exposure to smoke-free legislation on smoking cessation, as hypothesized in the International Tobacco Control (ITC) Conceptual Model. Methods: A nationally representative sample of Dutch smokers aged 15 years and older was surveyed during 4 consecutive annual surveys. Of the 1,820 baseline smokers, 1,012 participated in the fourth survey. Structural Equation Modeling was employed to test a model of the effects of individual exposure to smoke-free legislation through policy-specific variables (support for smoke-free legislation and awareness of the harm of [secondhand] smoking) and psychosocial mediators (attitudes, subjective norm, self-efficacy, and intention to quit) on quit attempts and quit success. Results: The effect of individual exposure to smoke-free legislation on smoking cessation was mediated by 1 pathway via support for smoke-free legislation, attitudes about quitting, and intention to quit smoking. Exposure to smoke-free legislation also influenced awareness of the harm of (secondhand) smoking, which in turn influenced the subjective norm about quitting. However, only attitudes about quitting were significantly associated with intention to quit smoking, whereas subjective norm and self-efficacy for quitting were not. Intention to quit predicted quit attempts and quit success, and self-efficacy for quitting predicted quit success. Conclusions: Our findings support the ITC Conceptual Model, which hypothesized that policies influence smoking cessation through policy-specific variables and psychosocial mediators. Smoke-free legislation may increase smoking cessation, provided that it succeeds in influencing support for the legislation. PMID:22491892

  15. Do changes in coping style explain the effectiveness of interventions for psychological morbidity in family carers of people with dementia? A systematic review and meta-analysis.

    Science.gov (United States)

    Li, Ryan; Cooper, Claudia; Austin, Allana; Livingston, Gill

    2013-02-01

    Observational studies find that family carers of people with dementia who use more emotional support and acceptance-based coping, and less dysfunctional coping, are less depressed and anxious. We hypothesized that interventions effective in reducing psychological symptoms would increase emotional support and acceptance-based coping, or decrease dysfunctional coping. We systematically reviewed randomized controlled trials published up to July 2011, of interventions for carers of people with dementia measuring coping and psychological morbidity. We rated study validity and reported findings. We conducted fixed-effect meta-analyses for interventions where possible. Eight of 433 papers identified by the search met inclusion criteria. All measured coping immediately after intervention. Two interventions significantly decreased depressive or anxiety symptoms: the smaller study found no change in dysfunctional coping. Neither measured emotional support and acceptance-based coping. Meta-analysis found that both group coping skills interventions alone (SMD = -0.39, 95% CI = -0.75 to -0.03, p = 0.04) and with behavioral activation (SMD = -0.26, 95% CI = -0.48 to -0.04, p = 0.02) significantly increased dysfunctional coping, while significantly reducing depressive symptoms. Positive coping (a mix of emotional and solution-focused strategies) increased (SMD = 0.28, 95% CI = 0.05-0.51, p = 0.02) with group coping skills interventions and behavioral activation. Contrary to our hypothesis, dysfunctional coping increased when carer depressive symptoms improved. There was preliminary evidence that emotional support and acceptance-based coping increased, as positive coping increased although solution-focused coping alone did not. More research is needed to elucidate whether successful interventions work through changing coping strategies immediately and in the longer term.

  16. Electrostatics Explains the Position-Dependent Effect of G⋅U Wobble Base Pairs on the Affinity of RNA Kissing Complexes.

    Science.gov (United States)

    Abi-Ghanem, Josephine; Rabin, Clémence; Porrini, Massimiliano; Dausse, Eric; Toulmé, Jean-Jacques; Gabelica, Valérie

    2017-10-06

    In the RNA realm, non-Watson-Crick base pairs are abundant and can affect both the RNA 3D structure and its function. Here, we investigated the formation of RNA kissing complexes in which the loop-loop interaction is modulated by non-Watson-Crick pairs. Mass spectrometry, surface plasmon resonance, and UV-melting experiments show that the G⋅U wobble base pair favors kissing complex formation only when placed at specific positions. We tried to rationalize this effect by molecular modeling, including molecular mechanics Poisson-Boltzmann surface area (MMPBSA) thermodynamics calculations and PBSA calculations of the electrostatic potential surfaces. Modeling reveals that the G⋅U stabilization is due to a specific electrostatic environment defined by the base pairs of the entire loop-loop region. The loop is not symmetric, and therefore the identity and position of each base pair matters. Predicting and visualizing the electrostatic environment created by a given sequence can help to design specific kissing complexes with high affinity, for potential therapeutic, nanotechnology or analytical applications. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Breast cancer screening among women in Namibia: explaining the effect of health insurance coverage and access to information on screening behaviours.

    Science.gov (United States)

    Kangmennaang, Joseph; Mkandawire, Paul; Luginaah, Isaac

    2017-09-01

    Breast cancer contributes substantially to morbidity and mortality in Namibia as is the case in most countries in Sub-Saharan Africa (SSA). However, there is a dearth of nationally representative studies that examine the odds of screening for breast cancer in Namibia and SSA at large. This paper aims to fill this gap by examining the determinants of breast cancer screening guided by the Health Belief Model. We applied hierarchical binary logit regression models to explore the determinants of breast cancer screening using the 2013 Namibia Demography and Health Survey (NDHS). We accounted for the effect of unobserved heterogeneity that may affect breast cancer, testing behaviours among women cluster level. The NDHS is a nationally representative dataset that has recently started to collect information on cancer screening. The results show that women who have health insurance coverage (odds ratio (OR) = 1.62, p ≤ 0.01), maintain contact with health professionals (OR = 1.47, p = 0.01), and who have secondary (OR = 1.38, p = 0.01) and higher (OR = 1.77, p ≤ 0.01) education were more likely to be screened for breast cancer. Factors that influence women's perception of their susceptibility to breast cancer such as birthing experience, age, region and place of residence were associated with screening in this context. Overall, the health belief model predicted women's testing behaviours and also revealed the absence of relevant risk factors in the NDHS data that might influence screening. Overall, our results show that strategies for early diagnosis of breast cancer should be given major priority by cancer control boards as well as ministries of health in SSA. These strategies should centre on early screening and may involve reducing or eliminating barriers to health care, access to relevant health information and encouraging breast self-examination.

  18. Endocytotic uptake of zoledronic acid by tubular cells may explain its renal effects in cancer patients receiving high doses of the compound.

    Directory of Open Access Journals (Sweden)

    Anja Verhulst

    Full Text Available Zoledronic acid, a highly potent nitrogen-containing bisphosphonate used for the treatment of pathological bone loss, is excreted unmetabolized via the kidney if not bound to the bone. In cancer patients receiving high doses of the compound renal excretion may be associated with acute tubular necrosis. The question of how zoledronic acid is internalized by renal tubular cells has not been answered until now. In the current work, using a primary human tubular cell culture system, the pathway of cellular uptake of zoledronic acid (fluorescently/radiolabeled and its cytotoxicity were investigated. Previous studies in our laboratory have shown that this primary cell culture model consistently mimics the physiological characteristics of molecular uptake/transport of the epithelium in vivo. Zoledronic acid was found to be taken up by tubular cells via fluid-phase-endocytosis (from apical and basolateral side as evidenced by its co-localization with dextran. Cellular uptake and the resulting intracellular level was twice as high from the apical side compared to the basolateral side. Furthermore, the intracellular zoledronic acid level was found to be dependent on the administered concentration and not saturable. Cytotoxic effects however, were only seen at higher administration doses and/or after longer incubation times. Although zoledronic acid is taken up by tubular cells, no net tubular transport could be measured. It is concluded that fluid-phase-endocytosis of zoledronic acid and cellular accumulation at high doses may be responsible for the acute tubular necrosis observed in some cancer patients receiving high doses of the compound.

  19. The effect of thermodynamic properties of solvent mixtures explains the difference between methanol and ethanol in C.antarctica lipase B catalyzed alcoholysis.

    Science.gov (United States)

    Sasso, Francesco; Kulschewski, Tobias; Secundo, Francesco; Lotti, Marina; Pleiss, Jürgen

    2015-11-20

    Kinetic modelling, molecular modelling, and experimental determination of the initial reaction velocity of lipase-catalyzed alcoholysis were combined to study the effect of the alcohol substrate to catalytic activity. The model system consisted of methanol or ethanol at varying concentrations, vinyl acetate as ester substrate 15.2% (v/v), toluene as organic solvent, water at a controlled thermodynamic activity of 0.09, and C. antarctica lipase B as enzyme. For both alcohol substrates, the initial reaction velocity increased sharply at low concentrations and reached a maximum at 0.7% (v/v) for methanol and 2% (v/v) for ethanol. For higher concentrations, the reaction rate decreased to a level of 74% and 60% of the peak value, respectively, due to substrate inhibition. The concentration dependency was described by a kinetic model, including a ping-pong bi-bi mechanism and competitive inhibition by the alcohol, and confirmed previous observations that methanol is more efficiently inhibiting the enzyme than ethanol. However, if the initial reaction velocity was expressed in terms of thermodynamic activity of the two alcohol substrates, the maximum of initial reaction velocity was similar for methanol (a MeOH(max)=0.19) and ethanol (a EtOH(max)=0.21). This was confirmed by molecular modelling which resulted in similar KM (0.22 and 0.19) and Ki values (0.44 and 0.49) for methanol and ethanol, respectively, if expressed in thermodynamic activities. Thus, the experimentally observed difference between methanol and ethanol is not due to differences in interaction with the enzyme but is a consequence of the thermodynamics of the substrate-solvent mixture. For low concentrations in toluene, the activity coefficient of methanol is 40% higher than the activity coefficient of ethanol (γ MeOH=8.5, γ EtOH=6.1). Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Explaining the Evolution of Poverty

    DEFF Research Database (Denmark)

    Arndt, Channing; Hussain, Azhar; Jones, Edward Samuel

    2012-01-01

    We provide a comprehensive approach for analyzing the evolution of poverty using Mozambique as a case study. Bringing together data from disparate sources, we develop a novel “back-casting” framework that links a dynamic computable general equilibrium model to a micro-simulation poverty module....... This framework provides a new approach to explaining and decomposing the evolution of poverty, as well as to examining rigorously the coherence between poverty, economic growth, and inequality outcomes. Finally, various simple but useful and rarely-applied approaches to considering regional changes in poverty...

  1. A More Practical Method for Explaining Equilibrium

    OpenAIRE

    Yi-Jang Yu

    2014-01-01

    The aim of this study is to suggest a more practical method for explaining market equilibrium in a two-dimensional risk-return world. Its main difference from textbook contents is to define, in both qualitative and quantitative ways, the environment or the system factor and treat it as an endogenous variable. Once the two-dimensional framework that is capable of managing uncertainty and environmental relationship can be reasonably established, a greater number of economic issues can be effect...

  2. Explaining variation in adult Anopheles indoor resting abundance: the relative effects of larval habitat proximity and insecticide-treated bed net use.

    Science.gov (United States)

    McCann, Robert S; Messina, Joseph P; MacFarlane, David W; Bayoh, M Nabie; Gimnig, John E; Giorgi, Emanuele; Walker, Edward D

    2017-07-17

    , and house structure modulated Anopheles abundance, but the effect varied with Anopheles species and sex. Variation in the abundance of indoor-resting Anopheles in rural houses of western Kenya varies with clearly identifiable factors. Results suggest that LLIN use continues to function in reducing vector abundance, and that larval source management in this region could lead to further reductions in malaria risk by reducing the amount of an obligatory resource for mosquitoes near people's homes.

  3. The NF-κB-like factor DIF could explain some positive effects of a mild stress on longevity, behavioral aging, and resistance to strong stresses in Drosophila melanogaster.

    Science.gov (United States)

    Le Bourg, Eric; Malod, Kévin; Massou, Isabelle

    2012-08-01

    A mild cold stress can have positive effects on longevity, aging and resistance to severe stresses in flies (heat, cold, fungal infection), but the causes of these effects remain elusive. In order to know whether these effects could be explained by the DIF transcription factor (a NF-κB-like factor in the Toll innate immunity pathway), the Dif ( 1 ) mutant and its control cn bw strain were subjected to a pretreatment by cold. The DIF factor seems to be involved in the response to fungal infection after a mild cold stress and in the resistance to heat. However, DIF seems to have no role in the increased longevity of non-infected flies and resistance to a severe cold shock, because the cold pretreatment slightly increased longevity in females, mainly in Dif ( 1 ) ones, and resistance to a long cold shock in both sexes of these strains.

  4. Explaining (Missing) Regulator Paradigm Shifts

    DEFF Research Database (Denmark)

    Wigger, Angela; Buch-Hansen, Hubert

    2014-01-01

    The global financial and economic crisis has prompted some scholars to suggest that a fundamental regulatory shift away from neoliberalism will take place – both in general and in the field of EU competition regulation. This paper shows that so far no radical break with the neoliberal type...... of competition regulation is heaving into sight. It sets out to explain this from the vantage point of a critical political economy perspective, which identifies the circumstances under which a crisis can result in a regulatory paradigm shift. Contrasting the current situation with the shift in EC/EU competition...... regulation after the crisis in the 1970s, the paper argues that the preconditions for a fundamental shift in this issue area are not present this time around. Several reasons account for this: the current crisis has been construed by economic and political elites as a crisis within and not of neoliberal...

  5. SOME THEORETICAL MODELS EXPLAINING ADVERTISING EFFECTS

    OpenAIRE

    Vasilica Magdalena SOMEŞFĂLEAN

    2014-01-01

    Persuade clients is still the main focus of the companies, using a set of methods and techniques designed to influence their behavior, in order to obtain better results (profits) over a longer period of time. Since the late nineteenth - early twentieth century, the american E.St.Elmo Lewis, considered a pioneer in advertising and sales, developed the first theory, AIDA model, later used by marketers and advertisers to develop a marketing communications strategy. Later studies have developed o...

  6. What explains consciousness? Or…What consciousness explains?

    Science.gov (United States)

    Dulany, Donelson E

    2014-01-01

    In this invited commentary I focus on the topic addressed in three papers: De Sousa's (2013[1617]) Toward an Integrative Theory of Consciousness, a monograph with Parts 1 & 2, as well as commentaries by Pereira (2013a[59]) and Hirstein (2013[42]). All three are impressively scholarly and can stand-and shout-on their own. But theory of consciousness? My aim is to slice that topic into the two fundamentally different kinds of theories of consciousness, say what appears to be an ideology, out of behaviourism into cognitivism, now also influencing the quest for an "explanation of consciousness" in cognitive neuroscience. I will then say what can be expected given what we know of the complexity of brain structure, the richness of a conscious "vocabulary", and current technological limits of brain imaging. This will then turn to the strategy for examining "what consciousness explains"-metatheory, theories, mappings, and a methodology of competitive support, a methodology especially important where there are competing commitments. There are also increasingly common identifications of methodological bias in, along with failures to replicate, studies reporting unconscious controls in decision, social priming-as there have been in perception, learning, problem solving, etc. The literature critique has provided evidence taken as reducing, and in some cases eliminating, a role for conscious controls-a position consistent with that ideology out of behaviourism into cognitivism. It is an ideological position that fails to recognize the fundamental distinction between theoretical and metaphysical assertions.

  7. Explain bioinformatics to your grandmother!

    Directory of Open Access Journals (Sweden)

    Virginie Bernard

    2013-10-01

    Full Text Available What are you working on? You have certainly been asked that question many times, whether it be at a Saturday night party, during a discussion with your neighbors, or at a family gathering. Communicating with a lay audience about scientific subjects and making them attractive is a difficult task. But difficult or not, you will have to do it for many years, not only with your family and friends, but also with your colleagues and collaborators. So, better learn now! Although not usually taught, the ability to explain your work to others is an essential skill in science, where communication plays a key role. Using some examples of the French Regional Student Group activities, we discuss here (i why it is important to have such communication skills, (ii how you can get involved in these activities by using existing resources or working with people who have previous experience, and (iii what you get out of this amazing experience. We aim to motivate you and provide you with tips and ideas to get involved in promoting scientific activities while getting all the benefits.

  8. Explaining the gender difference in nightmare frequency.

    Science.gov (United States)

    Schredl, Michael

    2014-01-01

    A recent meta-analysis showed a robust gender difference in nightmare frequency of medium effect size in adolescents and young adults: Women tend to report nightmares more frequently than men. The present study, carried out in an unselected student sample, indicates that 2 factors mediate the gender difference in nightmare frequency: neuroticism and overall dream recall frequency. The effect of neuroticism on the gender difference and the finding that the gender difference in nightmare frequency emerges at an age of about 10 years suggest that gender-specific socialization processes may play an important role in explaining the gender differences in nightmare frequency in adolescents and young to middle-aged adults. This idea is supported by the previous finding that nightmare frequency is related to sex role orientation. However, longitudinal studies are necessary to validate these hypotheses.

  9. Explaining the moral of the story.

    Science.gov (United States)

    Walker, Caren M; Lombrozo, Tania

    2017-10-01

    Although storybooks are often used as pedagogical tools for conveying moral lessons to children, the ability to spontaneously extract "the moral" of a story develops relatively late. Instead, children tend to represent stories at a concrete level - one that highlights surface features and understates more abstract themes. Here we examine the role of explanation in 5- and 6-year-old children's developing ability to learn the moral of a story. Two experiments demonstrate that, relative to a control condition, prompts to explain aspects of a story facilitate children's ability to override salient surface features, abstract the underlying moral, and generalize that moral to novel contexts. In some cases, generating an explanation is more effective than being explicitly told the moral of the story, as in a more traditional pedagogical exchange. These findings have implications for moral comprehension, the role of explanation in learning, and the development of abstract reasoning in early childhood. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Alcohol and breast cancer: the mechanisms explained.

    Science.gov (United States)

    Al-Sader, Hassen; Abdul-Jabar, Hani; Allawi, Zahra; Haba, Yasser

    2009-08-01

    Breast cancer is a leading cause of death amongst women, several studies have shown significant association between alcohol consumption and breast cancer. The aim of this overview is to highlight some of the mechanisms by which alcohol consumption could increase the risk of developing breast cancer. Using online Medline search engine, article containing details about mechanisms which explain the link between alcohol and breast cancer were examined. A number of mechanisms were found by which alcohol could increase the risk of breast cancer, alcohol's interaction and effect on oestrogen secretion; number of oestrogen receptors; the generation of acetaldehyde and hydroxyl free radicals; cells migration and metastasis; secretion of IGF1 and interaction with HRT and folate metabolism. In conclusion, it is essential for clinicians to understand these mechanisms and inform patients of the link between alcohol and breast cancer. Breast cancer; Alcohol; Mechanisms.

  11. Explaining the effects of a multifaceted intervention to improve inpatient care in rural Kenyan hospitals--interpretation based on retrospective examination of data from participant observation, quantitative and qualitative studies.

    Science.gov (United States)

    English, Mike; Nzinga, Jacinta; Mbindyo, Patrick; Ayieko, Philip; Irimu, Grace; Mbaabu, Lairumbi

    2011-12-02

    We have reported the results of a cluster randomized trial of rural Kenyan hospitals evaluating the effects of an intervention to introduce care based on best-practice guidelines. In parallel work we described the context of the study, explored the process and perceptions of the intervention, and undertook a discrete study on health worker motivation because this was felt likely to be an important contributor to poor performance in Kenyan public sector hospitals. Here, we use data from these multiple studies and insights gained from being participants in and observers of the intervention process to provide our explanation of how intervention effects were achieved as part of an effort to better understand implementation in low-income hospital settings. Initial hypotheses were generated to explain the variation in intervention effects across place, time, and effect measure (indicator) based on our understanding of theory and informed by our implementation experience and participant observations. All data sources available for hospitals considered as cases for study were then examined to determine if hypotheses were supported, rejected, or required modification. Data included transcriptions of interviews and group discussions, field notes and that from the detailed longitudinal quantitative investigation. Potentially useful explanatory themes were identified, discussed by the implementing and research team, revised, and merged as part of an iterative process aimed at building more generic explanatory theory. At the end of this process, findings were mapped against a recently reported comprehensive framework for implementation research. A normative re-educative intervention approach evolved that sought to reset norms and values concerning good practice and promote 'grass-roots' participation to improve delivery of correct care. Maximal effects were achieved when this strategy and external support supervision helped create a soft-contract with senior managers clarifying

  12. Explaining the effects of a multifaceted intervention to improve inpatient care in rural Kenyan hospitals -- interpretation based on retrospective examination of data from participant observation, quantitative and qualitative studies

    Directory of Open Access Journals (Sweden)

    English Mike

    2011-12-01

    Full Text Available Abstract Background We have reported the results of a cluster randomized trial of rural Kenyan hospitals evaluating the effects of an intervention to introduce care based on best-practice guidelines. In parallel work we described the context of the study, explored the process and perceptions of the intervention, and undertook a discrete study on health worker motivation because this was felt likely to be an important contributor to poor performance in Kenyan public sector hospitals. Here, we use data from these multiple studies and insights gained from being participants in and observers of the intervention process to provide our explanation of how intervention effects were achieved as part of an effort to better understand implementation in low-income hospital settings. Methods Initial hypotheses were generated to explain the variation in intervention effects across place, time, and effect measure (indicator based on our understanding of theory and informed by our implementation experience and participant observations. All data sources available for hospitals considered as cases for study were then examined to determine if hypotheses were supported, rejected, or required modification. Data included transcriptions of interviews and group discussions, field notes and that from the detailed longitudinal quantitative investigation. Potentially useful explanatory themes were identified, discussed by the implementing and research team, revised, and merged as part of an iterative process aimed at building more generic explanatory theory. At the end of this process, findings were mapped against a recently reported comprehensive framework for implementation research. Results A normative re-educative intervention approach evolved that sought to reset norms and values concerning good practice and promote 'grass-roots' participation to improve delivery of correct care. Maximal effects were achieved when this strategy and external support supervision helped

  13. Training science centre Explainers. The Techniquest experience

    Directory of Open Access Journals (Sweden)

    Colin Johnson

    2005-12-01

    Full Text Available Techniquest was established in 1986, and in 1995 moved to its current premises at Cardiff Bay, South Wales. This was the first purpose-built science centre in the UK. It receives around 200,000 visitors every year to its exhibition, and to its programmes for schools and public audiences in the theatre, laboratory, discovery room and planetarium. The author joined the Techniquest project in 1985, became a staff member in 1990 and was the Chief Executive from 1997 until his retirement in 2004. Techniquest has three “out-stations” in Wales, and is responsible for the supply and maintenance of exhibits to the Look Out Discovery Centre in Bracknell, England. There is a Techniquest gallery at the Lisbon Pavilhão do Conhecimento - Ciência Viva, and a traveling exhibition, SciQuest, in South Africa which was also supplied by Techniquest. All these centres rely on the effective intervention of “Explainers” (at Techniquest we call them “Helpers” to provide the best possible experience for visitors. At its most demanding, the tasks of an Explainer are varied and intensive, yet there may be times when the duties are mundane or even dull. When you rely on people to act as both hosts and housekeepers, to provide both support and stimulus, and to be both welcoming and watchful, you are asking a great deal. This article raises some of the issues concerned with the recruitment and retention of Explainers, their training and management, and the way in which their role is recognized and valued by the science centre as a whole.

  14. Phenotypic variance explained by local ancestry in admixed African Americans.

    Science.gov (United States)

    Shriner, Daniel; Bentley, Amy R; Doumatey, Ayo P; Chen, Guanjie; Zhou, Jie; Adeyemo, Adebowale; Rotimi, Charles N

    2015-01-01

    We surveyed 26 quantitative traits and disease outcomes to understand the proportion of phenotypic variance explained by local ancestry in admixed African Americans. After inferring local ancestry as the number of African-ancestry chromosomes at hundreds of thousands of genotyped loci across all autosomes, we used a linear mixed effects model to estimate the variance explained by local ancestry in two large independent samples of unrelated African Americans. We found that local ancestry at major and polygenic effect genes can explain up to 20 and 8% of phenotypic variance, respectively. These findings provide evidence that most but not all additive genetic variance is explained by genetic markers undifferentiated by ancestry. These results also inform the proportion of health disparities due to genetic risk factors and the magnitude of error in association studies not controlling for local ancestry.

  15. Effects of mushroom-derived ß-glucan rich polysaccharide extracts on nitric oxide production by bone marrow-derived macrophages and nuclear factor-kB transactivation in Caco-2 reporter cells: Can effects be explained by structure?

    NARCIS (Netherlands)

    Volman, J.J.; Helsper, J.P.F.G.; Wei, S.; Baars, J.J.P.; Griensven, van L.J.L.D.; Sonnenberg, A.S.M.; Mensink, R.P.; Plat, J.

    2010-01-01

    Mushrooms are known for their immune-modulating and anti-tumour properties. The polysaccharide fraction, mainly -glucans, is responsible for the immune-modulating effects. Fungal -glucans have been shown to activate leukocytes, which depend on structural characteristics of -glucans. As edible

  16. Explaining excess morbidity amongst homeless shelter users

    DEFF Research Database (Denmark)

    Benjaminsen, Lars; Birkelund, Jesper Fels

    2018-01-01

    AIMS: This article analyses excess morbidity amongst homeless shelter users compared to the general Danish population. The study provides an extensive control for confounding and investigates to what extent excess morbidity is explained by homelessness or other risk factors. METHODS: Data set...... background explain only a limited part. However, when conducting an extensive control for confounding, a significantly higher morbidity was identified amongst shelter users for infectious diseases, lung, skin, blood and digestive diseases, injuries, and poisoning. CONCLUSIONS: Ill health amongst homeless...... shelter users is widely explained by substance abuse problems and other risk factors. Nonetheless, for many diseases homelessness poses an additional risk to the health....

  17. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... Radiology and You Take our survey Sponsored by Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography ( ... pictures of the major blood vessels throughout your body. It may be performed with or without contrast ...

  18. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... by Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot ... d like to talk with you about magnetic resonance angiography, or as it’s commonly known, MRA. MRA ...

  19. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... Abdominal Ultrasound Video: Pelvic Ultrasound Medical Imaging Costs Radiology and You Take our survey Sponsored by Image/ ... Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot org Hello, I’m Dr. Elliot ...

  20. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

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    Full Text Available ... and You Take our survey Sponsored by Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography (MRA) ... Carotid Intima-Media Thickness Test Medical Imaging Costs Video: Abdominal Ultrasound Video: Pelvic Ultrasound Radiology and You ...

  1. Topology Explains Why Automobile Sunshades Fold Oddly

    Science.gov (United States)

    Feist, Curtis; Naimi, Ramin

    2009-01-01

    Automobile sunshades always fold into an "odd" number of loops. The explanation why involves elementary topology (braid theory and linking number, both explained in detail here with definitions and examples), and an elementary fact from algebra about symmetric group.

  2. Explorers Presentation: Explaining the Tides to Children

    OpenAIRE

    Institute, Marine

    2015-01-01

    Explaining the tides to children Presentation includes information about: Orbits of the Earth, Moon and Sun; Moon phases and the lunar cycle; Gravity; Gravity and the tide; Types of tides; The tides and me!; Tide tables; Extra insight

  3. Explainers – New energy for the museum

    Directory of Open Access Journals (Sweden)

    Sebastian Martin

    2008-12-01

    Full Text Available The Exploratorium explainer program is not only important to the young people involved, but is an integral part of the museum culture. This initiative that started to help the youth of our community has blossomed into a program that has been very helpful to the science centre. In fact, the institution would not be complete without the fresh energy of the explainers. They help the Exploratorium to continue to give the real pear to its public.

  4. Photoelectric properties of magnetically sensitive MOS structures

    Science.gov (United States)

    Davydov, V. N.; Lanskaya, O. G.; Lilenko, E. P.; Nesmelov, S. N.

    1998-05-01

    The photoelectric properties of MOS structures having compensation regions near the field electrode have been studied experimentally. It is shown that the presence of such regions can lead to the appearance of a number of features in the integrated photoelectric properties: the presence of a large photovoltage signal in enhancement, dependence of the form of the photovoltage frequency dependence on the intensity of the light flux, and distortion of the shape of the photovoltage signal in inversion. The presence of compensation regions can be established using measurements of the distribution of the photovoltage over the area of the structure and measurements of the voltage dependence of the phase of the integrated photovoltage signal. The increase or decrease of the photovoltage signal in enhancement after exposure to a weak magnetic field is due to the rearrangement of the impurity-defect structure in the near-surface layer of the semiconductor, leading to the appearance of compensated semiconductor regions near the field electrode.

  5. Explaining G20 and BRICS Compliance

    Directory of Open Access Journals (Sweden)

    Marina Larionova

    2016-11-01

    Full Text Available This article explores the internal and external factors influencing the compliance performance of the Group of 20 (G20 and the BRICS. The authors start with an overview of the G20 and BRICS compliance patterns using comparative data onthe number of commitments made by the two institutions, the level of institutional compliance, and distribution of commitments and compliance across issue areas. G20 compliance is traced since the leaders’ first 2008 summit in Washington. The BRICS compliance performance record includes data since the third stand alone summit in Sanya in 2011.The study then takes stock of compliance catalysts embedded in the summits’ discourse: priority placements, numerical targets, timelines, self-accountability pledges and mandates to implement and/or monitor implementation. The authors review trends in the use of catalysts in different years and issue areas and identify commonalities and differences.The analysis then turns to external causes of compliance and focuses on demand for collective actions and members’ collective power to respond and deliver on their pledges. Here the study explores whether the self-accountability mechanisms created by the institutions in response to the demand for effectiveness and legitimacy facilitate compliance.The article concludes by highlighting catalysts, causes of compliance and their combinations with the greatest power to encourage implementation, explaining trends in G20 and BRICS compliance performance. The data sets on G20 and BRICS differ in terms of scale. The G20 data set contains 1,511 commitments of which 114 have been monitored, and the BRICS data set contains 231 commitments of which 23 have been monitored.

  6. Explaining e-business adoption - Innovation & entrepreneurship in Dutch SMEs

    NARCIS (Netherlands)

    van der Veen, M.

    2005-01-01

    Explaining e-business adoptionThis dissertation deals with the explanation of e-business adoption in Dutch small and medium sized enterprises. The adoption of e-business plays an important part in making existing business more efficient and effective. Moreover, it is a tool for business development

  7. Explaining the judicial independence of international courts: a comparative analysis

    DEFF Research Database (Denmark)

    Beach, Derek

    What factors allow some international courts (ICs) to rule against the express preferences of powerful member states, whereas others routinely defer to governments? While judicial independence is not the only factor explaining the strength of a given international institution, it is a necessary...... condition. The paper first develops three sets of competing explanatory variables that potentially can explain variations in the judicial independence of ICs. The causal effects of these explanatory variables upon variance in judicial independence are investigated in a comparative analysis of the ACJ, ECJ...

  8. Explaining Racial Disparities in Infant Health in Brazil

    Science.gov (United States)

    Nyarko, Kwame A.; Lopez-Camelo, Jorge; Castilla, Eduardo E.

    2015-01-01

    Objectives. We sought to quantify how socioeconomic, health care, demographic, and geographic effects explain racial disparities in low birth weight (LBW) and preterm birth (PTB) rates in Brazil. Methods. We employed a sample of 8949 infants born between 1995 and 2009 in 15 cities and 7 provinces in Brazil. We focused on disparities in LBW (disparities. Results. The model explained 45% to 94% of LBW and 64% to 94% of PTB disparities between the African ancestry groups and European ancestry. Differences in prenatal care use and geographic location were the most important contributors, followed by socioeconomic differences. The model explained the majority of the disparities for mixed African ancestry and part of the disparity for African ancestry alone. Conclusions. Public policies to improve children’s health should target prenatal care and geographic location differences to reduce health disparities between infants of African and European ancestries in Brazil. PMID:26313046

  9. Explaining the VET Applied Research Developmental Framework

    Science.gov (United States)

    Simon, Linda; Beddie, Francesca M.

    2017-01-01

    This document explains the VET Applied Research Developmental Framework, created as part of a project that explored how the vocational education and training (VET) sector could broaden its engagement in Australia's research and development (R&D) and innovation systems. Achieving this engagement will rely significantly on building the…

  10. Explaining Violence in Sierra Leone's Civil War

    African Journals Online (AJOL)

    Explaining the violence of civil war is never a simple task for the scholar. In the case of the Sierra Leone, paradoxically, the task has in some ways been rendered more difficult by the sheer variety of compelling scholarship on the question. This paper seeks to identify the most useful of the explanations offered thus far, and ...

  11. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... Recently posted: Carotid Intima-Media Thickness Test Medical Imaging Costs Video: Abdominal Ultrasound Video: Pelvic Ultrasound Radiology and You Take our survey Sponsored by Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot ...

  12. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

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    Full Text Available ... Radiology and You Take our survey Sponsored by Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography ( ... problems, recent surgeries and allergies. If you’re female and there’s a possibility that you’re pregnant ...

  13. Adaptive hatching hypotheses do not explain asynchronous ...

    African Journals Online (AJOL)

    At the core of the suite of adaptive hatching hypotheses advanced to explain asynchronous hatching in birds is the assumption that if food is not limited then all the hatchlings will develop normally to adulthood. In this study Brown-headed Parrot Poicephalus cryptoxanthus chicks were hand fed and weighed on a daily basis.

  14. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... Sponsored by Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info ... I’d like to talk with you about magnetic resonance angiography, or as it’s commonly known, MRA. ...

  15. How Contracts and Enforcement Explain Transaction Outcomes

    NARCIS (Netherlands)

    Mooi, E.A.; Gilliland, D.I.

    2013-01-01

    This study considers the influence of contracts on enforcement and the subsequent performance impact of aligned and misaligned enforcement. We define enforcement as a corrective action aimed at remedying problems occurring in the transaction. First we explain the role of contracts and show that at

  16. Measuring and explaining house price developments

    NARCIS (Netherlands)

    De Vries, P.

    2010-01-01

    This study discusses ways of measuring and explaining the development of house prices. The goal of the research underpinning this dissertation was to develop a methodological framework for studying these developments. This framework relates, first, to correcting for changes in the composition of

  17. Explaining quality of life with crisis theory

    NARCIS (Netherlands)

    Sprangers, M.A.G.; van den Heuvel, W.J.A.; de Haes, H.C.J.M.

    2002-01-01

    Based on the premises of crisis theory. we expected cancer patients in-crisis to report a poorer quality of life (QL) and cancer patients post-crisis to report a similar level of overall QL in comparison to healthy individuals. To explain these hypothesized findings, we expected the coping resources

  18. John Watson's paradoxical struggle to explain Freud.

    Science.gov (United States)

    Rilling, M

    2000-03-01

    John Watson was fascinated by the discoveries of psychoanalysis, but he rejected Freud's central concept of the unconscious as incompatible with behaviorism. After failing to explain psychoanalysis in terms of William James's concept of habit, Watson borrowed concepts from classical conditioning to explain Freud's discoveries. Watson's famous experiment with Little Albert is interpreted not only in the context of Pavlovian conditioning but also as a psychoanalytically inspired attempt to capture simplified analogues of adult phobic behavior, including the "transference" of emotion in an infant. Watson used his behavioristic concept of conditioned emotional responses to compete with Freud's concepts of displacement and the unconscious transference of emotion. Behind a mask of anti-Freudian bias, Watson surprisingly emerges as a psychologist who popularized Freud and pioneered the scientific appraisal of his ideas in the laboratory.

  19. Explaining the Allocation of Regional Structural Funds

    DEFF Research Database (Denmark)

    Charron, Nicholas

    2016-01-01

    What regional factors can explain the heterogeneity in Structural Funds distribution to European Union regions? Past studies have shown that aside from the level of economic development and rates of unemployment, other political, and economic factors systematically explain why certain European...... Union regions receive greater funding than others, in particular where there is room for bargaining. In this article, a novel theory is posited which argues that the determination of Structural Funds is based on an interaction between a region’s formal institutions (the level of a regional autonomy......) and informal institutions (its level of quality of government). In cases of low regional autonomy, member states and European Union level actors prefer to allocate greater levels of Funds to regions with lower quality of government in order to increase cohesion. Yet in cases of high regional autonomy, risks...

  20. Children's Theories and the Drive to Explain

    Science.gov (United States)

    Schwitzgebel, Eric

    Debate has been growing in developmental psychology over how much the cognitive development of children is like theory change in science. Useful debate on this topic requires a clear understanding of what it would be for a child to have a theory. I argue that existing accounts of theories within philosophy of science and developmental psychology either are less precise than is ideal for the task or cannot capture everyday theorizing of the sort that children, if they theorize, must do. I then propose an account of theories that ties theories and explanation very closely together, treating theories primarily as products of a drive to explain. I clarify some of the positions people have taken regarding the theory theory of development, and I conclude by proposing that psychologists interested in the ''theory theory'' look for patterns of affect and arousal in development that would accompany the existence of a drive to explain.

  1. Explaining money creation by commercial banks

    DEFF Research Database (Denmark)

    Ravn, Ib

    2015-01-01

    created by commercial banks, as explained by the Bank of England recently (McLeay, Radia & Thomas, 2014b), is often met with incredulity: “What do you mean, created?” This paper introduces five easy-to-grasp analogies that educators and reformers may use to convey key money-creation concepts to a lay......Educators and economists concerned with monetary reform face the extraordinary challenge of explaining to the public and its elected representatives not only what a reformed system would look like, but also how the current system works. Centrally, the point that in a modern economy money is largely...... audience. The analogies offered include (1) money as patches in an expandable patchwork quilt that covers a nation’s real assets, (2) the money supply as water in a bathtub with a faucet and a drain, (3) money understood as debt in a model economy run by schoolchildren, (4) the misleading concept of a bank...

  2. Explaining the gender wage gap in Georgia

    OpenAIRE

    Khitarishvili, Tamar

    2009-01-01

    This paper evaluates gender wage differentials in Georgia between 2000 and 2004. Using ordinary least squares, we find that the gender wage gap in Georgia is substantially higher than in other transition countries. Correcting for sample selection bias using the Heckman approach further increases the gender wage gap. The Blinder Oaxaca decomposition results suggest that most of the wage gap remains unexplained. The explained portion of the gap is almost entirely attributed to industrial variab...

  3. IEE wiring regulations explained and illustrated

    CERN Document Server

    Scaddan, Brian

    2013-01-01

    The IEE Wiring Regulations Explained and Illustrated, Second Edition discusses the recommendations of the IEE Regulations for the Electrical Equipment of Buildings for the safe selection or erection of wiring installations. The book emphasizes earthing, bonding, protection, and circuit design of electrical wirings. The text reviews the fundamental requirements for safety, earthing systems, the earth fault loop impedance, and supplementary bonding. The book also describes the different types of protection, such as protection against mechanical damage, overcurrent, under voltage (which prevents

  4. Spatial inequalities explained - Evidence from Burkina Faso

    OpenAIRE

    Johannes Gräb; Michael Grimm

    2008-01-01

    The literature shows that regional disparities in growth and poverty are often relatively high, that these regional disparities do not necessarily disappear as the economies grow and develop and that these disparities are itself in many cases an important driver of the overall performance of an economy. In this paper we make use of the advantage of a multilevel random coefficient model to explain spatial disparities in incomes among Burkinab`e households. Our findings show that it is not a ge...

  5. Explaining convergence of oecd welfare states

    DEFF Research Database (Denmark)

    Schmitt, C.; Starke, Peter

    2011-01-01

    of conditional convergence helps to both better describe and explain the phenomenon. By applying error correction models, we examine conditional convergence of various types of social expenditure in 21 OECD countries between 1980 and 2005. Our empirical findings go beyond the existing literature in two respects....... First, we show that there is very strong evidence of convergence across all categories of social expenditure when conditional factors are taken into account. Second, we demonstrate that the speed of convergence is highly driven by globalization and European Union membership and shaped by existing...

  6. EVE: Explainable Vector Based Embedding Technique Using Wikipedia

    OpenAIRE

    Qureshi, M. Atif; Greene, Derek

    2017-01-01

    We present an unsupervised explainable word embedding technique, called EVE, which is built upon the structure of Wikipedia. The proposed model defines the dimensions of a semantic vector representing a word using human-readable labels, thereby it readily interpretable. Specifically, each vector is constructed using the Wikipedia category graph structure together with the Wikipedia article link structure. To test the effectiveness of the proposed word embedding model, we consider its usefulne...

  7. EXPLAINING THE ASSOCIATION BETWEEN INCARCERATION AND DIVORCE*

    Science.gov (United States)

    Siennick, Sonja E.; Stewart, Eric A.; Staff, Jeremy

    2014-01-01

    Recent studies have suggested that incarceration dramatically increases the odds of divorce, but we know little about the mechanisms that explain the association. This study uses prospective longitudinal data from a subset of married young adults in the National Longitudinal Study of Adolescent Health (N = 1,919) to examine whether incarceration is associated with divorce indirectly via low marital love, economic strain, relationship violence, and extramarital sex. The findings confirmed that incarcerations occurring during, but not before, a marriage were associated with an increased hazard of divorce. Incarcerations occurring during marriage also were associated with less marital love, more relationship violence, more economic strain, and greater odds of extramarital sex. Above-average levels of economic strain were visible among respondents observed preincarceration, but only respondents observed postincarceration showed less marital love, more relationship violence, and higher odds of extramarital sex than did respondents who were not incarcerated during marriage. These relationship problems explained approximately 40 percent of the association between incarceration and marital dissolution. These findings are consistent with theoretical predictions that a spouse’s incarceration alters the rewards and costs of the marriage and the relative attractiveness of alternative partners. PMID:25598544

  8. Explaining NDVI trends in northern Burkina Faso

    DEFF Research Database (Denmark)

    Rasmussen, Kjeld; Fensholt, Rasmus; Fog, Bjarne

    2014-01-01

    by a distinct spatial pattern and strongly dominated by negative trends in Normalized Difference Vegetation Index (NDVI). The aim of the paper is to explain this distinct pattern. When studied over the period 2000–2012, using NDVI data from the MODIS sensor the spatial pattern of NDVI trends indicates that non......-climatic factors are involved. By relating NDVI trends to landscape elements and land use change we demonstrate that NDVI trends in the north-western parts of the study area are mostly related to landscape elements, while this is not the case in the south-eastern parts, where rapidly changing land use, including....... expansion of irrigation, plays a major role. It is inferred that a process of increased redistribution of fine soil material, water and vegetation from plateaus and slopes to valleys, possibly related to higher grazing pressure, may provide an explanation of the observed pattern of NDVI trends. Further work...

  9. Can molecular cell biology explain chromosome motions?

    Directory of Open Access Journals (Sweden)

    Gagliardi L

    2011-05-01

    Full Text Available Abstract Background Mitotic chromosome motions have recently been correlated with electrostatic forces, but a lingering "molecular cell biology" paradigm persists, proposing binding and release proteins or molecular geometries for force generation. Results Pole-facing kinetochore plates manifest positive charges and interact with negatively charged microtubule ends providing the motive force for poleward chromosome motions by classical electrostatics. This conceptual scheme explains dynamic tracking/coupling of kinetochores to microtubules and the simultaneous depolymerization of kinetochore microtubules as poleward force is generated. Conclusion We question here why cells would prefer complex molecular mechanisms to move chromosomes when direct electrostatic interactions between known bound charge distributions can accomplish the same task much more simply.

  10. Explaining fast radio bursts through Dicke's superradiance

    Science.gov (United States)

    Houde, Martin; Mathews, Abhilash; Rajabi, Fereshteh

    2018-03-01

    Fast radio bursts (FRBs), characterized by strong bursts of radiation intensity at radio wavelengths lasting on the order of a millisecond, have yet to be firmly associated with a family, or families, of astronomical sources. It follows that despite the large number of proposed models, no well-defined physical process has been identified to explain this phenomenon. In this paper, we demonstrate how Dicke's superradiance, for which evidence has recently been found in the interstellar medium, can account for the characteristics associated with FRBs. Our analysis and modelling of previously detected FRBs suggest they could originate from regions in many ways similar to those known to harbour masers or megamasers, and result from the coherent radiation emanating from populations of molecules associated with large-scale entangled quantum mechanical states. We estimate this entanglement to involve as many as ˜1030 to ˜1032 molecules over distances spanning 100-1000 au.

  11. Explaining CMS lepton excesses with supersymmetry

    CERN Multimedia

    CERN. Geneva; Prof. Allanach, Benjamin

    2014-01-01

    1) Kostas Theofilatos will give an introduction to CMS result 2) Ben Allanach: Several CMS analyses involving di-leptons have recently reported small 2.4-2.8 sigma local excesses: nothing to get too excited about, but worth keeping an eye on nonetheless. In particular, a search in the $lljj p_T$(miss) channel, a search for $W_R$ in the $lljj$ channel and a di-leptoquark search in the $lljj$ channel and $ljj p_T$(miss) channel have all yielded small excesses. We interpret the first excess in the MSSM, showing that the interpretation is viable in terms of other constraints, despite only having squark masses of around 1 TeV. We can explain the last three excesses with a single R-parity violating coupling that predicts a non-zero contribution to the neutrinoless double beta decay rate.

  12. Explaining variation in Down's syndrome screening uptake

    DEFF Research Database (Denmark)

    Crombag, Neeltje M T H; Vellinga, Ynke E; Kluijfhout, Sandra A

    2014-01-01

    BACKGROUND: The offer of prenatal Down's syndrome screening is part of routine antenatal care in most of Europe; however screening uptake varies significantly across countries. Although a decision to accept or reject screening is a personal choice, it is unlikely that the widely differing uptake...... rates across countries can be explained by variation in individual values alone.The aim of this study was to compare Down's syndrome screening policies and programmes in the Netherlands, where uptake is relatively low ( 90% respectively....... RESULTS: There were many similarities in the demographics, healthcare systems, government abortion legislation and Down's syndrome screening policy across the studied countries. However, the additional cost for Down's syndrome screening over and above standard antenatal care in the Netherlands...

  13. Explaining African Participation in International Courts

    DEFF Research Database (Denmark)

    Gissel, Line Engbo; Brett, Peter

    2018-01-01

    Africa has more international courts than any other continent, yet International Relations scholarship has failed to explain this move to law on the African continent. This article provides such an explanation using Jean-François Bayart’s concept of extraversion. It shows how the creation...... of international courts in the 1990s and early 2000s was the result of extraverted strategies for attracting international resources and pre-empting donor pressures for political and legal reforms. By adopting these strategies, African states failed to behave in the ‘strategic’ manner anticipated by both...... Tribunal and International Criminal Court. Using the case studies of Zimbabwe and Kenya, it shows how global scripts were repeated by even those states which have, in recent years, most vocally asserted their national interests against these courts....

  14. Explaining polarization reversals in STEREO wave data

    Science.gov (United States)

    Breneman, A.; Cattell, C.; Wygant, J.; Kersten, K.; Wilson, L. B., III; Dai, L.; Colpitts, C.; Kellogg, P. J.; Goetz, K.; Paradise, A.

    2012-04-01

    Recently, Breneman et al. (2011) reported observations of large amplitude lightning and transmitter whistler mode waves from two STEREO passes through the inner radiation belt (L plane transverse to the magnetic field showed that the transmitter waves underwent periodic polarization reversals. Specifically, their polarization would cycle through a pattern of right-hand to linear to left-hand polarization at a rate of roughly 200 Hz. The lightning whistlers were observed to be left-hand polarized at frequencies greater than the lower hybrid frequency and less than the transmitter frequency (21.4 kHz) and right-hand polarized otherwise. Only right-hand polarized waves in the inner radiation belt should exist in the frequency range of the whistler mode and these reversals were not explained in the previous paper. We show, with a combination of observations and simulated wave superposition, that these polarization reversals are due to the beating of an incident electromagnetic whistler mode wave at 21.4 kHz and linearly polarized, symmetric lower hybrid sidebands Doppler-shifted from the incident wave by ±200 Hz. The existence of the lower hybrid waves is consistent with the parametric decay mechanism of Lee and Kuo (1984) whereby an incident whistler mode wave decays into symmetric, short wavelength lower hybrid waves and a purely growing (zero-frequency) mode. Like the lower hybrid waves, the purely growing mode is Doppler-shifted by ˜200 Hz as observed on STEREO. This decay mechanism in the upper ionosphere has been previously reported at equatorial latitudes and is thought to have a direct connection with explosive spread F enhancements. As such it may represent another dissipation mechanism of VLF wave energy in the ionosphere and may help to explain a deficit of observed lightning and transmitter energy in the inner radiation belts as reported by Starks et al. (2008).

  15. Explaining dehumanization among children: the interspecies model of prejudice.

    Science.gov (United States)

    Costello, Kimberly; Hodson, Gordon

    2014-03-01

    Although many theoretical approaches have emerged to explain prejudices expressed by children, none incorporate outgroup dehumanization, a key predictor of prejudice among adults. According to the Interspecies Model of Prejudice, beliefs in the human-animal divide facilitate outgroup prejudice through fostering animalistic dehumanization (Costello & Hodson, 2010). In the present investigation, White children attributed Black children fewer 'uniquely human' characteristics, representing the first systematic evidence of racial dehumanization among children (Studies 1 and 2). In Study 2, path analyses supported the Interspecies Model of Prejudice: children's human-animal divide beliefs predicted greater racial prejudice, an effect explained by heightened racial dehumanization. Similar patterns emerged among parents. Furthermore, parent Social Dominance Orientation predicted child prejudice indirectly through children's endorsement of a hierarchical human-animal divide and subsequent dehumanizing tendencies. Encouragingly, children's human-animal divide perceptions were malleable to an experimental prime highlighting animal-human similarity. Implications for prejudice interventions are considered. © 2012 The British Psychological Society.

  16. Predator mimicry, not conspicuousness, explains the efficacy of butterfly eyespots.

    Science.gov (United States)

    De Bona, Sebastiano; Valkonen, Janne K; López-Sepulcre, Andrés; Mappes, Johanna

    2015-05-07

    Large conspicuous eyespots on butterfly wings have been shown to deter predators. This has been traditionally explained by mimicry of vertebrate eyes, but recently the classic eye-mimicry hypothesis has been challenged. It is proposed that the conspicuousness of the eyespot, not mimicry, is what causes aversion due to sensory biases, neophobia or sensory overloads. We conducted an experiment to directly test whether the eye-mimicry or the conspicuousness hypothesis better explain eyespot efficacy. We used great tits (Parus major) as model predator, and tested their reaction towards animated images on a computer display. Birds were tested against images of butterflies without eyespots, with natural-looking eyespots, and manipulated spots with the same contrast but reduced resemblance to an eye, as well as images of predators (owls) with and without eyes. We found that mimetic eyespots were as effective as true eyes of owls and more efficient in eliciting an aversive response than modified, less mimetic but equally contrasting eyespots. We conclude that the eye-mimicry hypothesis explains our results better than the conspicuousness hypothesis and is thus likely to be an important mechanism behind the evolution of butterfly eyespots. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  17. Explaining Polarization Reversals in STEREO Wave Data

    Science.gov (United States)

    Breneman, A.; Cattell, C.; Wygant, J.; Kersten, K.; Wilson, L, B., III; Dai, L.; Colpitts, C.; Kellogg, P. J.; Goetz, K.; Paradise, A.

    2012-01-01

    Recently Breneman et al. reported observations of large amplitude lightning and transmitter whistler mode waves from two STEREO passes through the inner radiation belt (Lpaper. We show, with a combination of observations and simulated wave superposition, that these polarization reversals are due to the beating of an incident electromagnetic whistler mode wave at 21.4 kHz and linearly polarized, symmetric lower hybrid sidebands Doppler-shifted from the incident wave by +/-200 Hz. The existence of the lower hybrid waves is consistent with the parametric decay mechanism of Lee and Kuo whereby an incident whistler mode wave decays into symmetric, short wavelength lower hybrid waves and a purely growing (zero-frequency) mode. Like the lower hybrid waves, the purely growing mode is Doppler-shifted by 200 Hz as observed on STEREO. This decay mechanism in the upper ionosphere has been previously reported at equatorial latitudes and is thought to have a direct connection with explosive spread F enhancements. As such it may represent another dissipation mechanism of VLF wave energy in the ionosphere and may help to explain a deficit of observed lightning and transmitter energy in the inner radiation belts as reported by Starks et al.

  18. Explaining Global Secularity: Existential Security or Education?

    Directory of Open Access Journals (Sweden)

    Claude M. J. Braun

    2012-11-01

    Full Text Available At the time of data analysis for this report there were 193 countries in the world. Various institutions – the United Nations, the World Health Organization, the CIA, the World Values Survey, Gallup, and many others – have performed sophisticated statistical analyses on cross-national data. The present investigation demonstrates that valid and reliable data concerning religiosity and secularity exist for most countries and that these data are comparable. Cross-national data relating to social, political, economic and cultural aspects of life were tested for correlation with religiosity/secularity. In contrast to the most widely accepted general account of secularity, the Existential Security Framework (ESF; Norris & Inglehart, 2004, secularity was not most highly related to material security, though these were highly related. Rather, secularity was most strongly related to the degree of formal education attained. Material security explained no significant variance beyond education. Thus, religion’s primary function in the world today is being replaced, not so much by the pseudo-materialistic supplication for better living conditions as posited by the ESF, but by contemporary education – extensive knowledge of contemporary cultures, philosophy, modes of thought or processes of reasoning.

  19. Explaining Change in Language: A Cybersemiotic Perspective

    Directory of Open Access Journals (Sweden)

    Marcel Danesi

    2009-12-01

    Full Text Available One of the greatest conundrums in semiotics and linguistics is explaining why change occurs in communication systems. The descriptive apparatus of how change occurs has been developed in great detail since at least the nineteenth century, but a viable explanatory framework of why it occurs in the first place still seems to be clouded in vagueness. So far, only the so-called Principle of Least Effort has come forward to provide a suggestive psychobiological framework for understanding change in communication codes such as language. Extensive work in using this model has shown many fascinating things about language structure and how it evolves. However, the many findings need an integrative framework for shedding light on any generalities implicit in them. This paper argues that a new approach to the study of codes, called cybersemiotics, can be used to great advantage for assessing theoretical frameworks and notions such as the Principle of Least Effort. Amalgamating cybernetic and biosemiotic notions, this new science provides analysts with valuable insights on the raison d’être of phenomena such as linguistic change.

  20. Dark matter "transporting" mechanism explaining positron excesses

    Science.gov (United States)

    Kim, Doojin; Park, Jong-Chul; Shin, Seodong

    2018-04-01

    We propose a novel mechanism to explain the positron excesses, which are observed by satellite-based telescopes including PAMELA and AMS-02, in dark matter (DM) scenarios. The novelty behind the proposal is that it makes direct use of DM around the Galactic Center where DM populates most densely, allowing us to avoid tensions from cosmological and astrophysical measurements. The key ingredients of this mechanism include DM annihilation into unstable states with a very long laboratory-frame life time and their "retarded" decay near the Earth to electron-positron pair(s) possibly with other (in)visible particles. We argue that this sort of explanation is not in conflict with relevant constraints from big bang nucleosynthesis and cosmic microwave background. Regarding the resultant positron spectrum, we provide a generalized source term in the associated diffusion equation, which can be readily applicable to any type of two-"stage" DM scenarios wherein production of Standard Model particles occurs at completely different places from those of DM annihilation. We then conduct a data analysis with the recent AMS-02 data to validate our proposal.

  1. Can chunk size differences explain developmental changes in lexical learning?

    Directory of Open Access Journals (Sweden)

    Eleonore H.M. Smalle

    2016-01-01

    Full Text Available In three experiments, we investigated Hebb repetition learning (HRL differences between children and adults, as a function of the type of item (lexical vs. sub-lexical and the level of item-overlap between sequences. In a first experiment, it was shown that when non-repeating and repeating (Hebb sequences of words were all permutations of the same words, HRL was slower than when the sequences shared no words. This item-overlap effect was observed in both children and adults. In a second experiment, we used syllable sequences and we observed reduced HRL due to item-overlap only in children. The findings are explained within a chunking account of the HRL effect on the basis of which we hypothesize that children, compared with adults, chunk syllable sequences in smaller units. By hypothesis, small chunks are more prone to interference from anagram representations included in the filler sequences, potentially explaining the item-overlap effect in children. This hypothesis was tested in a third experiment with adults where we experimentally manipulated the chunk size by embedding pauses in the syllable sequences. Interestingly, we showed that imposing a small chunk size caused adults to show the same behavioral effects as those observed in children. Departing from the analogy between verbal HRL and lexical development, the results are discussed in light of the less-is-more hypothesis of age-related differences in language acquisition.

  2. Can Chunk Size Differences Explain Developmental Changes in Lexical Learning?

    Science.gov (United States)

    Smalle, Eleonore H M; Bogaerts, Louisa; Simonis, Morgane; Duyck, Wouter; Page, Michael P A; Edwards, Martin G; Szmalec, Arnaud

    2015-01-01

    In three experiments, we investigated Hebb repetition learning (HRL) differences between children and adults, as a function of the type of item (lexical vs. sub-lexical) and the level of item-overlap between sequences. In a first experiment, it was shown that when non-repeating and repeating (Hebb) sequences of words were all permutations of the same words, HRL was slower than when the sequences shared no words. This item-overlap effect was observed in both children and adults. In a second experiment, we used syllable sequences and we observed reduced HRL due to item-overlap only in children. The findings are explained within a chunking account of the HRL effect on the basis of which we hypothesize that children, compared with adults, chunk syllable sequences in smaller units. By hypothesis, small chunks are more prone to interference from anagram representations included in the filler sequences, potentially explaining the item-overlap effect in children. This hypothesis was tested in a third experiment with adults where we experimentally manipulated the chunk size by embedding pauses in the syllable sequences. Interestingly, we showed that imposing a small chunk size caused adults to show the same behavioral effects as those observed in children. Departing from the analogy between verbal HRL and lexical development, the results are discussed in light of the less-is-more hypothesis of age-related differences in language acquisition.

  3. Functional traits explain ecosystem function through opposing mechanisms.

    Science.gov (United States)

    Cadotte, Marc W

    2017-08-01

    The ability to explain why multispecies assemblages produce greater biomass compared to monocultures, has been a central goal in the quest to understand biodiversity effects on ecosystem function. Species contributions to ecosystem function can be driven by two processes: niche complementarity and a selection effect that is influenced by fitness (competitive) differences, and both can be approximated with measures of species' traits. It has been hypothesised that fitness differences are associated with few, singular traits while complementarity requires multidimensional trait measures. Here, using experimental data from plant assemblages, I show that the selection effect was strongest when trait dissimilarity was low, while complementarity was greatest with high trait dissimilarity. Selection effects were best explained by a single trait, plant height. Complementarity was correlated with dissimilarity across multiple traits, representing above and below ground processes. By identifying the relevant traits linked to ecosystem function, we obtain the ability to predict combinations of species that will maximise ecosystem function. © 2017 John Wiley & Sons Ltd/CNRS.

  4. Explaining clinical behaviors using multiple theoretical models.

    Science.gov (United States)

    Eccles, Martin P; Grimshaw, Jeremy M; MacLennan, Graeme; Bonetti, Debbie; Glidewell, Liz; Pitts, Nigel B; Steen, Nick; Thomas, Ruth; Walker, Anne; Johnston, Marie

    2012-10-17

    In the field of implementation research, there is an increased interest in use of theory when designing implementation research studies involving behavior change. In 2003, we initiated a series of five studies to establish a scientific rationale for interventions to translate research findings into clinical practice by exploring the performance of a number of different, commonly used, overlapping behavioral theories and models. We reflect on the strengths and weaknesses of the methods, the performance of the theories, and consider where these methods sit alongside the range of methods for studying healthcare professional behavior change. These were five studies of the theory-based cognitions and clinical behaviors (taking dental radiographs, performing dental restorations, placing fissure sealants, managing upper respiratory tract infections without prescribing antibiotics, managing low back pain without ordering lumbar spine x-rays) of random samples of primary care dentists and physicians. Measures were derived for the explanatory theoretical constructs in the Theory of Planned Behavior (TPB), Social Cognitive Theory (SCT), and Illness Representations specified by the Common Sense Self Regulation Model (CSSRM). We constructed self-report measures of two constructs from Learning Theory (LT), a measure of Implementation Intentions (II), and the Precaution Adoption Process. We collected data on theory-based cognitions (explanatory measures) and two interim outcome measures (stated behavioral intention and simulated behavior) by postal questionnaire survey during the 12-month period to which objective measures of behavior (collected from routine administrative sources) were related. Planned analyses explored the predictive value of theories in explaining variance in intention, behavioral simulation and behavior. Response rates across the five surveys ranged from 21% to 48%; we achieved the target sample size for three of the five surveys. For the predictor variables

  5. Explaining clinical behaviors using multiple theoretical models

    Directory of Open Access Journals (Sweden)

    Eccles Martin P

    2012-10-01

    Full Text Available Abstract Background In the field of implementation research, there is an increased interest in use of theory when designing implementation research studies involving behavior change. In 2003, we initiated a series of five studies to establish a scientific rationale for interventions to translate research findings into clinical practice by exploring the performance of a number of different, commonly used, overlapping behavioral theories and models. We reflect on the strengths and weaknesses of the methods, the performance of the theories, and consider where these methods sit alongside the range of methods for studying healthcare professional behavior change. Methods These were five studies of the theory-based cognitions and clinical behaviors (taking dental radiographs, performing dental restorations, placing fissure sealants, managing upper respiratory tract infections without prescribing antibiotics, managing low back pain without ordering lumbar spine x-rays of random samples of primary care dentists and physicians. Measures were derived for the explanatory theoretical constructs in the Theory of Planned Behavior (TPB, Social Cognitive Theory (SCT, and Illness Representations specified by the Common Sense Self Regulation Model (CSSRM. We constructed self-report measures of two constructs from Learning Theory (LT, a measure of Implementation Intentions (II, and the Precaution Adoption Process. We collected data on theory-based cognitions (explanatory measures and two interim outcome measures (stated behavioral intention and simulated behavior by postal questionnaire survey during the 12-month period to which objective measures of behavior (collected from routine administrative sources were related. Planned analyses explored the predictive value of theories in explaining variance in intention, behavioral simulation and behavior. Results Response rates across the five surveys ranged from 21% to 48%; we achieved the target sample size for three of

  6. Explaining Counterfeit Alcohol Purchases in Russia.

    Science.gov (United States)

    Kotelnikova, Zoya

    2017-04-01

    of surrogate alcohol (i.e., nonbeverage) are more influential in explaining why people purchase counterfeit alcohol. Further research on these 2 factors is needed to more fully understand the purchase and consumption of counterfeit alcoholic beverages. Copyright © 2017 by the Research Society on Alcoholism.

  7. Characteristics explaining performance in downhill mountain biking.

    Science.gov (United States)

    Chidley, Joel B; MacGregor, Alexandra L; Martin, Caoimhe; Arthur, Calum A; Macdonald, Jamie H

    2015-03-01

    To identify physiological, psychological, and skill characteristics that explain performance in downhill (DH) mountain-bike racing. Four studies were used to (1) identify factors potentially contributing to DH performance (using an expert focus group), (2) develop and validate a measure of rider skill (using video analysis and expert judge evaluation), (3) evaluate whether physiological, psychological, and skill variables contribute to performance at a DH competition, and (4) test the specific contribution of aerobic capacity to DH performance. STUDY 1 identified aerobic capacity, handgrip endurance, anaerobic power, rider skill, and self-confidence as potentially important for DH. In study 2 the rider-skill measure displayed good interrater reliability. Study 3 found that rider skill and handgrip endurance were significantly related to DH ride time (β=-0.76 and -0.14, respectively; R2=.73), with exploratory analyses suggesting that DH ride time may also be influenced by self-confidence and aerobic capacity. Study 4 confirmed aerobic capacity as an important variable influencing DH performance (for a DH ride, mean oxygen uptake was 49±5 mL·kg(-1)·min(-1), and 90% of the ride was completed above the 1st ventilatory threshold). In order of importance, rider skill, handgrip endurance, self-confidence, and aerobic capacity were identified as variables influencing DH performance. Practically, this study provides a novel assessment of rider skill that could be used by coaches to monitor training and identify talent. Novel intervention targets to enhance DH performance were also identified, including self-confidence and aerobic capacity.

  8. Explaining the gender gap in sickness absence.

    Science.gov (United States)

    Østby, K A; Mykletun, A; Nilsen, W

    2018-04-17

    In many western countries, women have a much higher rate of sickness absence than men. To what degree the gender differences in sickness absence are caused by gender differences in health is largely unknown. To assess to what degree the gender gap in sickness absence can be explained by health factors and work- and family-related stressors. Norwegian parents participating in the Tracking Opportunities and Problems (TOPP) study were asked about sickness absence and a range of factors possibly contributing to gender differences in sickness absence, including somatic and mental health, sleep problems, job control/demands, work-home conflicts, parent-child conflicts and stressful life events. Using a cross-sectional design, we did linear regression analyses, to assess the relative contribution from health and stressors. There were 557 study participants. Adjusting for health factors reduced the gender difference in sickness absence by 24%, while adjusting for stressors in the family and at work reduced the difference by 22%. A simultaneous adjustment for health factors and stressors reduced the difference in sickness absence by about 28%. Despite adjusting for a large number of factors, including both previously well-studied factors (e.g. health, job control/demands) and lesser-studied factors (parent-child conflict and sexual assault), this study found that most of the gender gap in sickness absence remains unexplained. Gender differences in health and stressors account for only part of the differences in sickness absence. Other factors must, therefore, exist outside the domains of health, work and family stressors.

  9. Supported Self-Explaining during Fraction Intervention

    Science.gov (United States)

    Fuchs, Lynn S.; Malone, Amelia S.; Schumacher, Robin F.; Namkung, Jessica; Hamlett, Carol L.; Jordan, Nancy C.; Siegler, Robert S.; Gersten, Russell; Changas, Paul

    2016-01-01

    The main purposes of this study were to test the effects of teaching at-risk 4th graders to provide explanations for their mathematics work and examine whether those effects occur by compensating for limitations in cognitive processes. We randomly assigned 212 children to 3 conditions: a control group and 2 variants of a multicomponent fraction…

  10. Explaining output volatility: The case of taxation

    DEFF Research Database (Denmark)

    Posch, Olaf

    This paper studies the effects of taxation on output volatility in OECD countries to shed light on the sources of observed heterogeneity over time and across countries. To this end, we derive tax effects on macro aggregates in a stochastic neoclassical model. As a result, taxes are shown to affect...

  11. Comparison of the effects explained by variations in the bovine PLAG1 and NCAPG genes on daily body weight gain, linear skeletal measurements and carcass traits in Japanese Black steers from a progeny testing program.

    Science.gov (United States)

    Hoshiba, Hiroshi; Setoguchi, Kouji; Watanabe, Toshio; Kinoshita, Akihiro; Mizoshita, Kazunori; Sugimoto, Yoshikazu; Takasuga, Akiko

    2013-07-01

    The c.1326T>G single nucleotide polymorphism (SNP) in the NCAPG gene, which leads to an amino acid change of Ile442 to Met442, was previously identified as a candidate causative variation for a bovine carcass weight quantitative trait loci (QTL) on chromosome 6, which was associated with linear skeletal measurement gains and daily body weight gain at puberty. Recently, we identified the stature quantitative trait nucleotides (QTNs) in the PLAG1-CHCHD7 intergenic region as the causative variations for another carcass weight QTL on chromosome 14. This study aimed to compare the effects of the two QTL on growth and carcass traits using 768 Japanese Black steers from a progeny testing program and to determine whether a genetic interaction was present between them. The FJX_250879 SNP representing the stature QTL was associated with linear skeletal measurements and average daily body weight gain at early and late periods during adolescence. A genetic interaction between FJX_250879 and NCAPG c.1326T>G was detected only for body and rump lengths. Both were associated with increased carcass weight and Longissimus muscle area, and NCAPG c.1326T>G was also associated with reduced subcutaneous fat thickness and increased carcass yield estimate. These results will provide useful information to improve carcass weight in Japanese Black cattle. © 2013 Japanese Society of Animal Science.

  12. Use of picture books to explain procedures.

    Science.gov (United States)

    2016-10-06

    A small study conducted at a Swedish hospital on the effect of giving picture books and picture sheets to prepare children for their procedures before and during day surgery is explored in this article.

  13. Evolutionary theories of aging can explain why we age.

    Science.gov (United States)

    Le Bourg, Eric

    2014-01-01

    Evolutionary theories of aging explain why we age. These theories take into account the fact that, in the wild, mean lifespan of many species is usually shorter than it could be in protected environments. In such conditions, because most of animals die before reaching old age, there is no selection in favor or against alleles with effects at old age. Alleles with negative effects at this age can thus accumulate in successive generations, particularly if they also have positive effects at young age and are thus retained by selection. This chapter describes the evolutionary theories of aging and their consequences for the understanding of the biology of aging as well as the challenges to these theories. It is argued that these theories offer a reasonable explanation to the existence of the aging process even if they can surely be refined.

  14. Explaining development aid allocation by growth: A meta study

    DEFF Research Database (Denmark)

    Doucouliagos, Hristos; Paldam, Martin

    The empirical literature explaining the driving forces behind the flows of development aid consists of (at least) 166 studies. One factor that has been analyzed in 30 of these studies is  growth in the recipient country. A priori the effect may as well be positive as negative. This is  an interes......The empirical literature explaining the driving forces behind the flows of development aid consists of (at least) 166 studies. One factor that has been analyzed in 30 of these studies is  growth in the recipient country. A priori the effect may as well be positive as negative. This is......  an interesting factor for two reasons: (1) It is relatively easy to interpret the results, and (2) it  is an important piece in the picture which suggests aid ineffectiveness. The paper is a meta-analysis of the 211 growth-aid estimates found in the 30 empirical studies. Additionally, we present new evidence...

  15. Self-explaining agents in virtual training

    NARCIS (Netherlands)

    Harbers, M.; Bosch, K. van den; Meyer, J.J.C.

    2008-01-01

    Virtual training systems are increasingly used for the training of complex, dynamic tasks. To give trainees the opportunity to train autonomously, intelligent agents are used to generate the behavior of the virtual players in the training scenario. For effective training however, trainees should be

  16. Acidified infant formula explained | Labuschagne | South African ...

    African Journals Online (AJOL)

    The development of effective methods to prevent acute gastroenteritis is an important goal for infant health. Exclusive breastfeeding and postponement of complementary foods until the age of six months is recommended for healthy infants. However, at times, infant formula is required. Various types are commercially ...

  17. Infrastructure features outperform environmental variables explaining rabbit abundance around motorways.

    Science.gov (United States)

    Planillo, Aimara; Malo, Juan E

    2018-01-01

    Human disturbance is widespread across landscapes in the form of roads that alter wildlife populations. Knowing which road features are responsible for the species response and their relevance in comparison with environmental variables will provide useful information for effective conservation measures. We sampled relative abundance of European rabbits, a very widespread species, in motorway verges at regional scale, in an area with large variability in environmental and infrastructure conditions. Environmental variables included vegetation structure, plant productivity, distance to water sources, and altitude. Infrastructure characteristics were the type of vegetation in verges, verge width, traffic volume, and the presence of embankments. We performed a variance partitioning analysis to determine the relative importance of two sets of variables on rabbit abundance. Additionally, we identified the most important variables and their effects model averaging after model selection by AICc on hypothesis-based models. As a group, infrastructure features explained four times more variability in rabbit abundance than environmental variables, being the effects of the former critical in motorway stretches located in altered landscapes with no available habitat for rabbits, such as agricultural fields. Model selection and Akaike weights showed that verge width and traffic volume are the most important variables explaining rabbit abundance index, with positive and negative effects, respectively. In the light of these results, the response of species to the infrastructure can be modulated through the modification of motorway features, being some of them manageable in the design phase. The identification of such features leads to suggestions for improvement through low-cost corrective measures and conservation plans. As a general indication, keeping motorway verges less than 10 m wide will prevent high densities of rabbits and avoid the unwanted effects that rabbit populations

  18. Attitudes Vs. Cognitions: Explaining Long-Term Watergate Effects.

    Science.gov (United States)

    Becker, Lee B.; Towers, Wayne M.

    The political scandals known as Watergate provided an unusual opportunity to study the importance of attitudinal and cognitive variables in media research. In order to assess the impact of Watergate during the months preceding the 1974 Congressional elections, 339 personal interviews were conducted during October with a probability sample of…

  19. Visceral Effect of Female Genital Mutilation as Explained by Married ...

    African Journals Online (AJOL)

    These included self-reproach, poor self-image, painful menstrual periods and severe bleeding. Men whose partners were genitally mutilated confirmed that their wives faced these challenges. Based on these findings, it is recommended that counselling and education should be given to groups that still enforce this practice.

  20. Does cultural integration explain a mental health advantage for adolescents?

    Science.gov (United States)

    Bhui, Kamaldeep S; Lenguerrand, Erik; Maynard, Maria J; Stansfeld, Stephen A; Harding, Seeromanie

    2012-06-01

    A mental health advantage has been observed among adolescents in urban areas. This prospective study tests whether cultural integration measured by cross-cultural friendships explains a mental health advantage for adolescents. A prospective cohort of adolescents was recruited from 51 secondary schools in 10 London boroughs. Cultural identity was assessed by friendship choices within and across ethnic groups. Cultural integration is one of four categories of cultural identity. Using gender-specific linear-mixed models we tested whether cultural integration explained a mental health advantage, and whether gender and age were influential. Demographic and other relevant factors, such as ethnic group, socio-economic status, family structure, parenting styles and perceived racism were also measured and entered into the models. Mental health was measured by the Strengths and Difficulties Questionnaire as a 'total difficulties score' and by classification as a 'probable clinical case'. A total of 6643 pupils in first and second years of secondary school (ages 11-13 years) took part in the baseline survey (2003/04) and 4785 took part in the follow-up survey in 2005-06. Overall mental health improved with age, more so in male rather than female students. Cultural integration (friendships with own and other ethnic groups) was associated with the lowest levels of mental health problems especially among male students. This effect was sustained irrespective of age, ethnicity and other potential explanatory variables. There was a mental health advantage among specific ethnic groups: Black Caribbean and Black African male students (Nigerian/Ghanaian origin) and female Indian students. This was not fully explained by cultural integration, although cultural integration was independently associated with better mental health. Cultural integration was associated with better mental health, independent of the mental health advantage found among specific ethnic groups: Black Caribbean and

  1. Does cultural integration explain a mental health advantage for adolescents?

    Science.gov (United States)

    Bhui, Kamaldeep S; Lenguerrand, Erik; Maynard, Maria J; Stansfeld, Stephen A; Harding, Seeromanie

    2012-01-01

    Background A mental health advantage has been observed among adolescents in urban areas. This prospective study tests whether cultural integration measured by cross-cultural friendships explains a mental health advantage for adolescents. Methods A prospective cohort of adolescents was recruited from 51 secondary schools in 10 London boroughs. Cultural identity was assessed by friendship choices within and across ethnic groups. Cultural integration is one of four categories of cultural identity. Using gender-specific linear-mixed models we tested whether cultural integration explained a mental health advantage, and whether gender and age were influential. Demographic and other relevant factors, such as ethnic group, socio-economic status, family structure, parenting styles and perceived racism were also measured and entered into the models. Mental health was measured by the Strengths and Difficulties Questionnaire as a ‘total difficulties score’ and by classification as a ‘probable clinical case’. Results A total of 6643 pupils in first and second years of secondary school (ages 11–13 years) took part in the baseline survey (2003/04) and 4785 took part in the follow-up survey in 2005–06. Overall mental health improved with age, more so in male rather than female students. Cultural integration (friendships with own and other ethnic groups) was associated with the lowest levels of mental health problems especially among male students. This effect was sustained irrespective of age, ethnicity and other potential explanatory variables. There was a mental health advantage among specific ethnic groups: Black Caribbean and Black African male students (Nigerian/Ghanaian origin) and female Indian students. This was not fully explained by cultural integration, although cultural integration was independently associated with better mental health. Conclusions Cultural integration was associated with better mental health, independent of the mental health advantage

  2. Explaining CO2 fluctuations observed in snowpacks

    Science.gov (United States)

    Graham, Laura; Risk, David

    2018-02-01

    Winter soil carbon dioxide (CO2) respiration is a significant and understudied component of the global carbon (C) cycle. Winter soil CO2 fluxes can be surprisingly variable, owing to physical factors such as snowpack properties and wind. This study aimed to quantify the effects of advective transport of CO2 in soil-snow systems on the subdiurnal to diurnal (hours to days) timescale, use an enhanced diffusion model to replicate the effects of CO2 concentration depletions from persistent winds, and use a model-measure pairing to effectively explore what is happening in the field. We took continuous measurements of CO2 concentration gradients and meteorological data at a site in the Cape Breton Highlands of Nova Scotia, Canada, to determine the relationship between wind speeds and CO2 levels in snowpacks. We adapted a soil CO2 diffusion model for the soil-snow system and simulated stepwise changes in transport rate over a broad range of plausible synthetic cases. The goal was to mimic the changes we observed in CO2 snowpack concentration to help elucidate the mechanisms (diffusion, advection) responsible for observed variations. On subdiurnal to diurnal timescales with varying winds and constant snow levels, a strong negative relationship between wind speed and CO2 concentration within the snowpack was often identified. Modelling clearly demonstrated that diffusion alone was unable to replicate the high-frequency CO2 fluctuations, but simulations using above-atmospheric snowpack diffusivities (simulating advective transport within the snowpack) reproduced snow CO2 changes of the observed magnitude and speed. This confirmed that wind-induced ventilation contributed to episodic pulsed emissions from the snow surface and to suppressed snowpack concentrations. This study improves our understanding of winter CO2 dynamics to aid in continued quantification of the annual global C cycle and demonstrates a preference for continuous wintertime CO2 flux measurement systems.

  3. Explaining CO2 fluctuations observed in snowpacks

    Directory of Open Access Journals (Sweden)

    L. Graham

    2018-02-01

    Full Text Available Winter soil carbon dioxide (CO2 respiration is a significant and understudied component of the global carbon (C cycle. Winter soil CO2 fluxes can be surprisingly variable, owing to physical factors such as snowpack properties and wind. This study aimed to quantify the effects of advective transport of CO2 in soil–snow systems on the subdiurnal to diurnal (hours to days timescale, use an enhanced diffusion model to replicate the effects of CO2 concentration depletions from persistent winds, and use a model–measure pairing to effectively explore what is happening in the field. We took continuous measurements of CO2 concentration gradients and meteorological data at a site in the Cape Breton Highlands of Nova Scotia, Canada, to determine the relationship between wind speeds and CO2 levels in snowpacks. We adapted a soil CO2 diffusion model for the soil–snow system and simulated stepwise changes in transport rate over a broad range of plausible synthetic cases. The goal was to mimic the changes we observed in CO2 snowpack concentration to help elucidate the mechanisms (diffusion, advection responsible for observed variations. On subdiurnal to diurnal timescales with varying winds and constant snow levels, a strong negative relationship between wind speed and CO2 concentration within the snowpack was often identified. Modelling clearly demonstrated that diffusion alone was unable to replicate the high-frequency CO2 fluctuations, but simulations using above-atmospheric snowpack diffusivities (simulating advective transport within the snowpack reproduced snow CO2 changes of the observed magnitude and speed. This confirmed that wind-induced ventilation contributed to episodic pulsed emissions from the snow surface and to suppressed snowpack concentrations. This study improves our understanding of winter CO2 dynamics to aid in continued quantification of the annual global C cycle and demonstrates a preference for continuous wintertime CO2 flux

  4. Explaining Returns with Cash-Flow Proxies

    OpenAIRE

    Peter Hecht; Tuomo Vuolteenaho

    2005-01-01

    Stock returns are correlated with contemporaneous earnings growth, dividend growth, future real activity, and other cash-flow proxies. The correlation between cash-flow proxies and stock returns may arise from association of cash-flow proxies with one-period expected returns, cash-flow news, and/or expected-return news. We use Campbell's (1991) return decomposition to measure the relative importance of these three effects in regressions of returns on cash-flow proxies. In some of the popular ...

  5. Development and Assessment of Self-explaining Skills in College Chemistry Instruction

    Science.gov (United States)

    Villalta-Cerdas, Adrian

    The prevalent trend in chemistry instruction relies on what has been described as the classroom game. In this model, students take a passive role and the instructor does all the explaining (thinking), and learning is trivialized to knowing the correct answers (memorizing) and being able to produce them when prompted (regurgitating). The generation of explanations is central to scientific and technological development. In the process of figuring out explanations, the generation of inferences relies on the application of skills associated with scientific behaviors (e.g., analytical reasoning and critical thinking). The process of explanation generation causes a deeper analysis and revision of the scientific models, thus impacting the conceptual understanding of such models. Although the process of generating authentic explanations is closer to the experience of doing science, this process is seldom replicated in science instruction. Self-explaining refers to the generation of inferences about causal connections between objects and events. In science, this may be summarized as making sense of how and why actual or hypothetical phenomena take place. Research findings in educational psychology show that implementing activities that elicit self-explaining improves learning in general and specifically enhances authentic learning in the sciences. Research also suggests that self-explaining influences many aspects of cognition, including acquisition of problem-solving skills and conceptual understanding. Although the evidence that links self-explaining and learning is substantial, most of the research has been conducted in experimental settings. The purpose of this work was to advance knowledge in this area by investigating the effect of different self-explaining tasks on self-explaining behavior and the effect of engaging in different levels of self-explaining on learning chemistry concepts. Unlike most of the research in the field, this work did not focus on advancing

  6. Explaining variation in the uptake of HPV vaccination in England

    Directory of Open Access Journals (Sweden)

    Whynes David K

    2011-03-01

    intentions surveys and pilot studies. Deprivation, the ethnic composition of the population, the effectiveness of primary care and the acceptability of childhood vaccinations are salient factors in explaining local HPV vaccine uptake in England.

  7. Can model-free reinforcement learning explain deontological moral judgments?

    Science.gov (United States)

    Ayars, Alisabeth

    2016-05-01

    Dual-systems frameworks propose that moral judgments are derived from both an immediate emotional response, and controlled/rational cognition. Recently Cushman (2013) proposed a new dual-system theory based on model-free and model-based reinforcement learning. Model-free learning attaches values to actions based on their history of reward and punishment, and explains some deontological, non-utilitarian judgments. Model-based learning involves the construction of a causal model of the world and allows for far-sighted planning; this form of learning fits well with utilitarian considerations that seek to maximize certain kinds of outcomes. I present three concerns regarding the use of model-free reinforcement learning to explain deontological moral judgment. First, many actions that humans find aversive from model-free learning are not judged to be morally wrong. Moral judgment must require something in addition to model-free learning. Second, there is a dearth of evidence for central predictions of the reinforcement account-e.g., that people with different reinforcement histories will, all else equal, make different moral judgments. Finally, to account for the effect of intention within the framework requires certain assumptions which lack support. These challenges are reasonable foci for future empirical/theoretical work on the model-free/model-based framework. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Explaining the footsteps, belly dancer, Wenceslas, and kickback illusions

    Science.gov (United States)

    Howe, Piers D. L.; Thompson, Peter G.; Anstis, Stuart M.; Sagreiya, Hersh; Livingstone, Margaret S.

    2009-01-01

    The footsteps illusion (FI) demonstrates that an object’s background can have a profound effect on the object’s perceived speed. This illusion consists of a yellow bar and a blue bar that move over a black-and-white, striped background. Although the bars move at a constant rate, they appear to repeatedly accelerate and decelerate in antiphase with each other. Previously, this illusion has been explained in terms of the variations in contrast at the leading and trailing edges of the bars that occur as the bars traverse the striped background. Here, we show that this explanation is inadequate and instead propose that for each bar, the bar’s leading edge, trailing edge, lateral edges, and the surrounding background edges all contribute to the bar’s perceived speed and that the degree to which each edge contributes to the motion percept is determined by that edge’s contrast. We show that this theory can explain all the data on the FI as well as the belly dancer and Wenceslas illusions. We conclude by presenting a new illusion, the kickback illusion, which, although geometrically similar to the FI, is mediated by a different mechanism, namely, reverse phi motion. PMID:17209742

  9. Efferent feedback can explain many hearing phenomena

    Science.gov (United States)

    Holmes, W. Harvey; Flax, Matthew R.

    2015-12-01

    The mixed mode cochlear amplifier (MMCA) model was presented at the last Mechanics of Hearing workshop [4]. The MMCA consists principally of a nonlinear feedback loop formed when an efferent-controlled outer hair cell (OHC) is combined with the cochlear mechanics and the rest of the relevant neurobiology. Essential elements of this model are efferent control of the OHC motility and a delay in the feedback to the OHC. The input to the MMCA is the passive travelling wave. In the MMCA amplification is localized where both the neural and tuned mechanical systems meet in the Organ of Corti (OoC). The simplest model based on this idea is a nonlinear delay line resonator (DLR), which is mathematically described by a nonlinear delay-differential equation (DDE). This model predicts possible Hopf bifurcations and exhibits its most interesting behaviour when operating near a bifurcation. This contribution presents some simulation results using the DLR model. These show that various observed hearing phenomena can be accounted for by this model, at least qualitatively, including compression effects, two-tone suppression and some forms of otoacoustic emissions (OAEs).

  10. Globalization and Inequality: Explaining American Exceptionalism

    Science.gov (United States)

    Massey, Douglas S.

    2013-01-01

    Globalization creates pressure for greater inequality throughout the world, but these pressures are expressed more fully in the United States than in other developed nations. Although the distribution of US income before taxes is no more unequal than other nations, after taxes it is considerably less egalitarian. This occurs because of specific institutional arrangements that fail to redistribute income effectively and allow the pressures of globalization to be fully realized. These arrangements represent a shift from the past and were deliberately enacted over the past two decades with divergent consequences for those at the top and bottom of the socioeconomic hierarchy. The realignment of the US political economy can ultimately be traced to America’s legacy of racism. Once leaders in the Democratic party sought to include African Americans in the benefits of Roosevelt’s New Deal, support for economic populism evaporated in the middle and working classes. The advantage of the wealth is further enhanced by a political system in which those with money are better able to have their interests served legislatively than the poor or working classes. PMID:24298198

  11. Does Specialization Explain Marriage Penalties and Premiums?

    Science.gov (United States)

    Killewald, Alexandra; Gough, Margaret

    2013-01-01

    Married men’s wage premium is often attributed to within-household specialization: men can devote more effort to wage-earning when their wives assume responsibility for household labor. We provide a comprehensive evaluation of the specialization hypothesis, arguing that, if specialization causes the male marriage premium, married women should experience wage losses. Furthermore, specialization by married parents should augment the motherhood penalty and the fatherhood premium for married as compared to unmarried parents. Using fixed-effects models and data from the NLSY79, we estimate within-gender differences in wages according to marital status and between-gender differences in the associations between marital status and wages. We then test whether specialization on time use, job traits, and tenure accounts for the observed associations. Results for women do not support the specialization hypothesis. Childless men and women both receive a marriage premium. Marriage augments the fatherhood premium but not the motherhood penalty. Changes in own and spousal employment hours, job traits, and tenure appear to benefit both married men and women, although men benefit more. Marriage changes men’s labor market behavior in ways that augment wages, but these changes do not appear to occur at the expense of women’s wages. PMID:24039271

  12. Catchment Concentraton-Discharge Archetypes Explained

    Science.gov (United States)

    Gall, H. E.; Jawitz, J. W.; Rao, P. C.

    2012-12-01

    archetypical C-Q patterns. The model simulations reproduce the three major C-Q patterns observed in published data, offering valuable insight into catchment processes. The findings have important implications for effective catchment management and water quality improvement.

  13. Elements Explaining Learning Clinical Reasoning Using Simulation Games

    Directory of Open Access Journals (Sweden)

    Jaana-Maija Koivisto

    2016-12-01

    Full Text Available This article presents the findings on which elements in a game-based simulation affect learning clinical reasoning in nursing education. By using engaging gaming elements in virtual simulations and integrating the clinical reasoning process into game mechanics, games can enhance learning clinical reasoning and offer meaningful learning experiences. The study was designed to explore how nursing students experience gaming and learning when playing a simulation game, as well as which gaming elements explain learning clinical reasoning. The data was collected by questionnaire from nursing students (N = 166 in autumn 2014 over thirteen gaming sessions. The findings showed that usability, application of nursing knowledge, and exploration have the most impact on learning clinical reasoning when playing simulation games. Findings also revealed that authentic patient-related experiences, feedback, and reflection have an indirect effect on learning clinical reasoning. Based on these results, more efficient simulation games to improve clinical reasoning may be developed.   

  14. Doing business with CERN: a new website explains everything

    CERN Multimedia

    CERN Bulletin

    2011-01-01

    At CERN, procuring all supplies and services is the job of the Procurement and Industrial Services (PI) group of the Finance and Procurement Department. Managing about 30,000 new orders and contracts every year, the Group recently launched a brand-new website where CERN and its external partners can find all the useful information to effectively do business together.   When the Laboratory needs to buy goods or services, the PI group comes into play and makes sure that this happens according to the established rules and procedures. “CERN procures supplies and services and awards orders and contracts in compliance with the principles of transparency and impartiality,” explains Anders Unnervik, Head of Procurement and Industrial Services in the Finance and Procurement Department (FP). “CERN’s tendering procedures are selective but they are designed to guarantee fair competition.” The invitations to tender are, in principle, limited to firms establish...

  15. [To explain is to narrate. How to visualize scientific data].

    Science.gov (United States)

    Hawtin, Nigel

    2014-01-01

    When you try to appeal a vast ranging audience, as it occurs at the New Scientist that addresses scientists as well as the general public, your scientific visual explainer must be succinct, clear, accurate and easily understandable. In order to reach this goal, your message should provide only the main data, the ones that allow you to balance information and clarity: information should be put into context and all the extra details should be cut down. It is very important, then, to know well both your audience and the subject you are going to describe, as graphic masters of the past, like William Playfair and Charles Minard, have taught us. Moreover, you should try to engage your reader connecting the storytelling power of words and the driving force of the graphics: colours, visual elements, typography. To be effective, in fact, an infographic should not only be truthful and functional, but also elegant, having style and legibility.

  16. Maternal characteristics largely explain poor pregnancy outcome after hyperemesis gravidarum.

    Science.gov (United States)

    Roseboom, Tessa J; Ravelli, Anita C J; van der Post, Joris A; Painter, Rebecca C

    2011-05-01

    To describe the characteristics of women who suffer from hyperemesis gravidarum, and explore the independent effect of hyperemesis gravidarum on pregnancy outcome. In The Netherlands Perinatal Registry, we used all data on singleton pregnancies of at least 24 weeks and 500 g without congenital anomalies in the years 2000-2006. We examined the characteristics of women who suffered from hyperemesis gravidarum and their children. Women who suffered from hyperemesis gravidarum were slightly younger; more often primiparous, of lower socio-economic status, of non-Western descent and substance abusers; had more often conceived through assisted reproduction techniques and more often had pre-existing hypertension, diabetes mellitus and psychiatric diseases than women who did not suffer from hyperemesis gravidarum. Also, their pregnancies were more often complicated by hypertension and diabetes and they more often carried a female fetus. Pregnancies complicated by hyperemesis gravidarum significantly more often had an adverse outcome (prematurity or birth weight below the 10th percentile). The increased risk of adverse pregnancy outcomes after hyperemesis gravidarum was largely explained by the differences in maternal characteristics (crude OR 1.22 (95% CI 1.10-1.36), adjusted OR was 1.07 (95% CI 0.95-1.19)). Hyperemesis gravidarum is associated with adverse pregnancy outcomes. This is largely explained by differences in maternal characteristics. Given the impact of the early environment on later health (which is independent of size at birth), studies that aim to assess the long-term consequences of hyperemesis gravidarum need to be given high priority. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  17. Explaining the diversity of motivations behind community renewable energy

    International Nuclear Information System (INIS)

    Bauwens, Thomas

    2016-01-01

    Community-based renewable energy initiatives may be important actors in the transition toward low-carbon energy systems. In turn, stimulating investments in renewable energy production at the community level requires a better understanding of investors' motives. This paper aims to study the heterogeneity of motivations that drive individuals to participate in community renewable energy projects and the underlying explanatory factors behind this, as well as the implications for their level of engagement in initiatives. Based on quantitative data from an original survey conducted with two renewable energy cooperatives in Flanders, the statistical analysis shows that cooperative members should not be considered as one homogeneous group. Several categories of members with different motives and levels of engagement can be distinguished. This heterogeneity is explained by contrasts in terms of institutional settings, spatial patterns and attitudes to the diffusion of institutional innovations. Regarding policy implications, the findings suggest that this heterogeneity should be taken into account in designing more effective supporting policies to stimulate investments at the community level. The activation of social norms is also shown to be a promising mechanism for triggering investment decisions, although the implications of its interplay with economic incentives should be further explored. - Highlights: •Community-based energy projects are important actors in the low-carbon transition. •The diversity of motivations and level of engagement among members is analysed. •Several segments of members with different characteristics are distinguished. •Institutional, spatial and innovation diffusion dimensions explain this diversity. •This heterogeneity among investors should be taken into account in policy-making.

  18. Four loci explain 83% of size variation in the horse.

    Directory of Open Access Journals (Sweden)

    Shokouh Makvandi-Nejad

    Full Text Available Horse body size varies greatly due to intense selection within each breed. American Miniatures are less than one meter tall at the withers while Shires and Percherons can exceed two meters. The genetic basis for this variation is not known. We hypothesize that the breed population structure of the horse should simplify efforts to identify genes controlling size. In support of this, here we show with genome-wide association scans (GWAS that genetic variation at just four loci can explain the great majority of horse size variation. Unlike humans, which are naturally reproducing and possess many genetic variants with weak effects on size, we show that horses, like other domestic mammals, carry just a small number of size loci with alleles of large effect. Furthermore, three of our horse size loci contain the LCORL, HMGA2 and ZFAT genes that have previously been found to control human height. The LCORL/NCAPG locus is also implicated in cattle growth and HMGA2 is associated with dog size. Extreme size diversification is a hallmark of domestication. Our results in the horse, complemented by the prior work in cattle and dog, serve to pinpoint those very few genes that have played major roles in the rapid evolution of size during domestication.

  19. Does the General Strain Theory Explain Gambling and Substance Use?

    Science.gov (United States)

    Greco, Romy; Curci, Antonietta

    2017-09-01

    General Strain Theory (GST: Agnew Criminology 30:47-87, 1992) posits that deviant behaviour results from adaptation to strain and the consequent negative emotions. Empirical research on GST has mainly focused on aggressive behaviours, while only few research studies have considered alternative manifestations of deviance, like substance use and gambling. The aim of the present study is to test the ability of GST to explain gambling behaviours and substance use. Also, the role of family in promoting the adoption of gambling and substance use as coping strategies was verified. Data from 266 families with in mean 8 observations for each group were collected. The multilevel nature of the data was verified before appropriate model construction. The clustered nature of gambling data was analysed by a two-level Hierarchical Linear Model while substance use was analysed by Multivariate Linear Model. Results confirmed the effect of strain on gambling and substance use while the positive effect of depressive emotions on these behaviours was not supported. Also, the impact of family on the individual tendency to engage in addictive behaviours was confirmed only for gambling.

  20. THE ROLE OF BEHAVIORAL ECONOMICS IN EXPLAINING CONSUMPTION DECISION

    Directory of Open Access Journals (Sweden)

    Mihaela Andreea STROE

    2015-07-01

    Full Text Available The new economic approach starts from the idea that the individual does not need food, but feels the need to feed, or do not require newspapers, but feels the need of information. In this way, those who changes are not human preferences, but the way we satisfy them. At this stage of the paper, we explain the inconsistency in consumer preferences and the exceptions to the standard theory by making light upon what is called in behavioral economics: the effects of property, loss aversion and framing effects. In which concerns the standard economic model, it seems that there are discrepancies between objective measures of sources of comfort / discomfort and measures reported subjective sensations. Many defenders of classical model would argue that the measures are not reported subjective feelings of economic phenomena and therefore are not of interest to economists. However, when such feelings and sensations affect or may affect future decisions, things become relevant for the economy. Limited Rationality implies both that the agent is imperfectly informed decision-making in a complex and dynamic environment, and a limited ability processing.

  1. Explaining Infinite Series--An Exploration of Students' Images

    Science.gov (United States)

    Champney, Danielle Dawn

    2013-01-01

    This study uses self-generated representations (SGR)--images produced in the act of explaining--as a means of uncovering what university calculus students understand about infinite series convergence. It makes use of student teaching episodes, in which students were asked to explain to a peer what that student might have missed had they been…

  2. Democracy in the Arab World : Explaining the Deficit | CRDI - Centre ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Democracy in the Arab World : Explaining the Deficit. Couverture du livre Democracy in the Arab World : Explaining the Deficit. Directeur(s) : Ibrahim Elbadawi et Samir Makdisi. Maison(s) d'édition : Routledge, CRDI. 10 septembre 2010. ISBN : 9780415779999. 352 pages. e-ISBN : 9781552504918. Téléchargez le PDF.

  3. Good for the group? Explaining apparent group-level selection

    NARCIS (Netherlands)

    Smallegange, I.M.; Egas, M.

    2015-01-01

    The idea that group selection can explain adaptive trait evolution is still controversial. Recent empirical work proposes evidence for group-level adaptation in a social spider, but the findings can also be explained from an individual-level perspective. The challenge remains to identify situations

  4. Hypotheses to explain the origin of species in Amazonia

    Directory of Open Access Journals (Sweden)

    J. Haffer

    Full Text Available The main hypotheses proposed to explain barrier formation separating populations and causing the differentiation of species in Amazonia during the course of geological history are based on different factors, as follow: (1 Changes in the distribution of land and sea or in the landscape due to tectonic movements or sea level fluctuations (Paleogeography hypothesis, (2 the barrier effect of Amazonian rivers (River hypothesis, (3 a combination of the barrier effect of broad rivers and vegetational changes in northern and southern Amazonia (River-refuge hypothesis, (4 the isolation of humid rainforest blocks near areas of surface relief in the periphery of Amazonia separated by dry forests, savannas and other intermediate vegetation types during dry climatic periods of the Tertiary and Quaternary (Refuge hypothesis, (5 changes in canopy-density due to climatic reversals (Canopy-density hypothesis (6 the isolation and speciation of animal populations in small montane habitat pockets around Amazonia due to climatic fluctuations without major vegetational changes (Museum hypothesis, (7 competitive species interactions and local species isolations in peripheral regions of Amazonia due to invasion and counterinvasion during cold/warm periods of the Pleistocene (Disturbance-vicariance hypothesis and (8 parapatric speciation across steep environmental gradients without separation of the respective populations (Gradient hypothesis. Several of these hypotheses probably are relevant to a different degree for the speciation processes in different faunal groups or during different geological periods. The basic paleogeography model refers mainly to faunal differentiation during the Tertiary and in combination with the Refuge hypothesis. Milankovitch‡ cycles leading to global main hypotheses proposed to explain barrier formation separating populations and causing the differentiation of species in Amazonia during the course of geological history are based on

  5. Hypotheses to explain the origin of species in Amazonia.

    Science.gov (United States)

    Haffer, J

    2008-11-01

    The main hypotheses proposed to explain barrier formation separating populations and causing the differentiation of species in Amazonia during the course of geological history are based on different factors, as follow: (1) Changes in the distribution of land and sea or in the landscape due to tectonic movements or sea level fluctuations (Paleogeography hypothesis), (2) the barrier effect of Amazonian rivers (River hypothesis), (3) a combination of the barrier effect of broad rivers and vegetational changes in northern and southern Amazonia (River-refuge hypothesis), (4) the isolation of humid rainforest blocks near areas of surface relief in the periphery of Amazonia separated by dry forests, savannas and other intermediate vegetation types during dry climatic periods of the Tertiary and Quaternary (Refuge hypothesis), (5) changes in canopy-density due to climatic reversals (Canopy-density hypothesis) (6) the isolation and speciation of animal populations in small montane habitat pockets around Amazonia due to climatic fluctuations without major vegetational changes (Museum hypothesis), (7) competitive species interactions and local species isolations in peripheral regions of Amazonia due to invasion and counterinvasion during cold/warm periods of the Pleistocene (Disturbance-vicariance hypothesis) and (8) parapatric speciation across steep environmental gradients without separation of the respective populations (Gradient hypothesis). Several of these hypotheses probably are relevant to a different degree for the speciation processes in different faunal groups or during different geological periods. The basic paleogeography model refers mainly to faunal differentiation during the Tertiary and in combination with the Refuge hypothesis. Milankovitch cycles leading to global main hypotheses proposed to explain barrier formation separating populations and causing the differentiation of species in Amazonia during the course of geological history are based on different

  6. Gaining from explaining: Learning improves from explaining to fictitious others on video, not from writing to them

    NARCIS (Netherlands)

    Hoogerheide, Vincent; Deijkers, Lian; Loyens, Sofie M M; Heijltjes, Anita; van Gog, Tamara

    2016-01-01

    Two experiments investigated whether studying a text with an "explanation intention" and then actually explaining it to (fictitious) other students in writing, would yield the same benefits as previously found for explaining on video. Experiment 1 had participants first studying a text either with

  7. How older persons explain why they became victims of abuse.

    Science.gov (United States)

    Mysyuk, Yuliya; Westendorp, Rudi Gerardus Johannes; Lindenberg, Jolanda

    2016-09-01

    elder abuse greatly impacts the quality of life of older individuals. Prevalence rates range from 3 to 30% depending on the definition used. Only about a dozen studies have explored how older victims themselves experience and explain abuse. It is essential that healthcare professionals understand the perceptions of older victims as they are among the most important groups to handle and report abuse. a qualitative study on the perceptions and experiences of victims of elder abuse was conducted using in-depth semi-structured interviews. abused individuals living independently, in residential care facilities and nursing homes. six males and 11 females aged 63-90 years. the main causes of abuse identified by older victims themselves were mutual dependency between victim and perpetrator, power and control imbalances, loneliness and a marginalised social position of older persons. Effects of abuse included negative feelings, physical and psychological distress, a change of personal norms and values, changed perspectives on money and low self-efficacy. These differential effects depended upon the types of abuse experienced and the relationship with the perpetrator. Coping strategies mentioned by victims were seeking informal or professional help and using self-help strategies. older victims perceive abuse differently depending on the expected acceptability of the type(s) of abuse experienced and the anticipated stigma associated with the perpetrator involved. The effects and chosen coping strategies are influenced by these considerations and therewith also influence their help-seeking behaviour. Healthcare professionals are encouraged to use these findings in practice to prevent, detect and intervene in elder abuse. © The Author 2016. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Improving the explainability of Random Forest classifier - user centered approach.

    Science.gov (United States)

    Petkovic, Dragutin; Altman, Russ; Wong, Mike; Vigil, Arthur

    2018-01-01

    Machine Learning (ML) methods are now influencing major decisions about patient care, new medical methods, drug development and their use and importance are rapidly increasing in all areas. However, these ML methods are inherently complex and often difficult to understand and explain resulting in barriers to their adoption and validation. Our work (RFEX) focuses on enhancing Random Forest (RF) classifier explainability by developing easy to interpret explainability summary reports from trained RF classifiers as a way to improve the explainability for (often non-expert) users. RFEX is implemented and extensively tested on Stanford FEATURE data where RF is tasked with predicting functional sites in 3D molecules based on their electrochemical signatures (features). In developing RFEX method we apply user-centered approach driven by explainability questions and requirements collected by discussions with interested practitioners. We performed formal usability testing with 13 expert and non-expert users to verify RFEX usefulness. Analysis of RFEX explainability report and user feedback indicates its usefulness in significantly increasing explainability and user confidence in RF classification on FEATURE data. Notably, RFEX summary reports easily reveal that one needs very few (from 2-6 depending on a model) top ranked features to achieve 90% or better of the accuracy when all 480 features are used.

  9. Explainable expert systems: A research program in information processing

    Science.gov (United States)

    Paris, Cecile L.

    1993-01-01

    Our work in Explainable Expert Systems (EES) had two goals: to extend and enhance the range of explanations that expert systems can offer, and to ease their maintenance and evolution. As suggested in our proposal, these goals are complementary because they place similar demands on the underlying architecture of the expert system: they both require the knowledge contained in a system to be explicitly represented, in a high-level declarative language and in a modular fashion. With these two goals in mind, the Explainable Expert Systems (EES) framework was designed to remedy limitations to explainability and evolvability that stem from related fundamental flaws in the underlying architecture of current expert systems.

  10. Explaining European fungal fruiting phenology with climate variability.

    Science.gov (United States)

    Andrew, Carrie; Heegaard, Einar; Høiland, Klaus; Senn-Irlet, Beatrice; Kuyper, Thomas W; Krisai-Greilhuber, Irmgard; Kirk, Paul M; Heilmann-Clausen, Jacob; Gange, Alan C; Egli, Simon; Bässler, Claus; Büntgen, Ulf; Boddy, Lynne; Kauserud, Håvard

    2018-04-14

    Here we assess the impact of geographically dependent (latitude, longitude and altitude) changes in bioclimatic (temperature, precipitation and primary productivity) variability on fungal fruiting phenology across Europe. Two main nutritional guilds of fungi, saprotrophic and ectomycorrhizal, were further separated into spring and autumn fruiters. We used a path-analysis to investigate how biogeographic patterns in fungal fruiting phenology coincided with seasonal changes in climate and primary production. Across central to northern Europe, mean fruiting varied by approximately 25 days, primarily with latitude. Altitude affected fruiting by up to 30 days, with spring delays and autumnal accelerations. Fruiting was as much explained by the effects of bioclimatic variability as by their large-scale spatial patterns. Temperature drove fruiting of autumnal ectomycorrhizal and saprotrophic, as well as spring saprotrophic groups, while primary production and precipitation were major drivers for spring-fruiting ectomycorrhizal fungi. Species-specific phenology predictors were not stable, instead deviating from the overall mean. There is significant likelihood that further climatic change, especially in temperature, will impact fungal phenology patterns at large spatial scales. The ecological implications are diverse, potentially affecting food webs (asynchrony), nutrient cycling and the timing of nutrient availability in ecosystems. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  11. Modeling as an Anchoring Scientific Practice for Explaining Friction Phenomena

    Science.gov (United States)

    Neilson, Drew; Campbell, Todd

    2017-12-01

    Through examining the day-to-day work of scientists, researchers in science studies have revealed how models are a central sense-making practice of scientists as they construct and critique explanations about how the universe works. Additionally, they allow predictions to be made using the tenets of the model. Given this, alongside research suggesting that engaging students in developing and using models can have a positive effect on learning in science classrooms, the recent national standards documents in science education have identified developing and using models as an important practice students should engage in as they apply and refine their ideas with peers and teachers in explaining phenomena or solving problems in classrooms. This article details how students can be engaged in developing and using models to help them make sense of friction phenomena in a high school conceptual physics classroom in ways that align with visions for teaching and learning outlined in the Next Generation Science Standards. This particular unit has been refined over several years to build on what was initially an inquiry-based unit we have described previously. In this latest iteration of the friction unit, students developed and refined models through engaging in small group and whole class discussions and investigations.

  12. Hemispheric Asymmetry of Global Warming Explained by a Conceptual Model

    Science.gov (United States)

    Funke, C. S.; Alexeev, V. A.

    2017-12-01

    Polar Amplification, the process of amplified warming at high latitudes, manifests itself differently in the Arctic and Antarctic. Not only is the temperature increase in the Arctic more pronounced than in the Antarctic but the dramatic sea ice decline in the Arctic over the last few decades also contrasts sharply with trendless to weak positive trend of Antarctic sea ice throughout the same period. This asymmetric behavior is often partly attributed to the differences in configuration of continents in the Arctic and Antarctic: the Arctic Ocean is surrounded by land while the Southern Ocean has a continent in the middle. A simple conceptual energy balance model of Budyko-Sellers type, accounting for differences between the Northern and Southern hemispheres, is applied to study the mechanisms of climate sensitivity to a variety of forcings. Asymmetry in major modes of variability is explained using an eigenmode analysis of the linearized model. Negative forcings over Antarctica such as from ozone depletion were found to have an amplified effect on southern hemisphere climate and may be an important cause of the muted warming and slightly positive Antarctic sea ice trend.

  13. Explaining employment relationships with social exchange and job embeddedness.

    Science.gov (United States)

    Hom, Peter W; Tsui, Anne S; Wu, Joshua B; Lee, Thomas W; Zhang, Ann Yan; Fu, Ping Ping; Li, Lan

    2009-03-01

    The research reported in this article clarifies how employee-organization relationships (EORs) work. Specifically, the authors tested whether social exchange and job embeddedness mediate how mutual-investment (whereby employers offer high inducements to employees for their high contributions) and over-investment (high inducements without corresponding high expected contributions) EOR approaches, which are based on Tsui, Pearce, Porter, and Tripoli's (1997) framework, affect quit propensity and organizational commitment. Two studies evaluated these intervening mechanisms. Study 1 surveyed 953 Chinese managers attending part-time master of business administration (MBA) programs in China, whereas Study 2 collected cross-sectional and longitudinal data from 526 Chinese middle managers in 41 firms. Standard and multilevel causal modeling techniques affirmed that social exchange and job embeddedness translate EOR influence. A second multilevel test using lagged outcome measures further established that job embeddedness mediates long-term EOR effects over 18 months. These findings corroborate prevailing views that social exchange explains how mutual- and over-investment EORs motivate greater workforce commitment and loyalty. This study enriches EOR perspectives by identifying job embeddedness as another mediator that is more enduring than social exchange. (c) 2009 APA, all rights reserved.

  14. Persistent villi hypoperfusion explains intramucosal acidosis in sheep endotoxemia

    NARCIS (Netherlands)

    Dubin, Arnaldo; Edul, Vanina Siham Kanoore; Pozo, Mario Omar; Murias, Gastón; Canullán, Carlos Manuel; Martins, Enrique Francisco; Ferrara, Gonzalo; Canales, Héctor Saul; Laporte, Mercedes; Estenssoro, Elisa; Ince, Can

    2008-01-01

    OBJECTIVE: To test the hypothesis that persistent villi hypoperfusion explains intramucosal acidosis after endotoxemic shock resuscitation. DESIGN: Controlled experimental study. SETTING: University-based research laboratory. SUBJECTS: A total of 14 anesthetized, mechanically ventilated sheep.

  15. Can inflation explain the second law of thermodynamics

    International Nuclear Information System (INIS)

    Page, D.N.; Pennsylvania State Univ., University Park

    1984-01-01

    The inflationary model of the universe can explain several of the cosmological conundra that are mysteries in the standard hot big bang model. Paul Davies has suggested that inflation can also explain the second law of thermodynamics, which describes the time asymmetry of the universe. Here several difficulties with this suggestion are noted showing how the present inflationary models must assume the arrow of time rather than explaining it. If the second law is formulated as a consequence of the hypothesis that there were no long-range spatial correlations in the initial state of the universe, it is shown how some of the cosmological conundra might be explained even without inflation. But if the ultimate explanation is to include inflation, three essential elements remain to be demonstrated which are listed. (author)

  16. Agricultural management explains historic changes in regional soil carbon stocks

    Science.gov (United States)

    van Wesemael, Bas; Paustian, Keith; Meersmans, Jeroen; Goidts, Esther; Barancikova, Gabriela; Easter, Mark

    2010-01-01

    Agriculture is considered to be among the economic sectors having the greatest greenhouse gas mitigation potential, largely via soil organic carbon (SOC) sequestration. However, it remains a challenge to accurately quantify SOC stock changes at regional to national scales. SOC stock changes resulting from SOC inventory systems are only available for a few countries and the trends vary widely between studies. Process-based models can provide insight in the drivers of SOC changes, but accurate input data are currently not available at these spatial scales. Here we use measurements from a soil inventory dating from the 1960s and resampled in 2006 covering the major soil types and agricultural regions in Belgium together with region-specific land use and management data and a process-based model. The largest decreases in SOC stocks occurred in poorly drained grassland soils (clays and floodplain soils), consistent with drainage improvements since 1960. Large increases in SOC in well drained grassland soils appear to be a legacy effect of widespread conversion of cropland to grassland before 1960. SOC in cropland increased only in sandy lowland soils, driven by increasing manure additions. Modeled land use and management impacts accounted for more than 70% of the variation in observed SOC changes, and no bias could be demonstrated. There was no significant effect of climate trends since 1960 on observed SOC changes. SOC monitoring networks are being established in many countries. Our results demonstrate that detailed and long-term land management data are crucial to explain the observed SOC changes for such networks. PMID:20679194

  17. Agricultural management explains historic changes in regional soil carbon stocks.

    Science.gov (United States)

    van Wesemael, Bas; Paustian, Keith; Meersmans, Jeroen; Goidts, Esther; Barancikova, Gabriela; Easter, Mark

    2010-08-17

    Agriculture is considered to be among the economic sectors having the greatest greenhouse gas mitigation potential, largely via soil organic carbon (SOC) sequestration. However, it remains a challenge to accurately quantify SOC stock changes at regional to national scales. SOC stock changes resulting from SOC inventory systems are only available for a few countries and the trends vary widely between studies. Process-based models can provide insight in the drivers of SOC changes, but accurate input data are currently not available at these spatial scales. Here we use measurements from a soil inventory dating from the 1960s and resampled in 2006 covering the major soil types and agricultural regions in Belgium together with region-specific land use and management data and a process-based model. The largest decreases in SOC stocks occurred in poorly drained grassland soils (clays and floodplain soils), consistent with drainage improvements since 1960. Large increases in SOC in well drained grassland soils appear to be a legacy effect of widespread conversion of cropland to grassland before 1960. SOC in cropland increased only in sandy lowland soils, driven by increasing manure additions. Modeled land use and management impacts accounted for more than 70% of the variation in observed SOC changes, and no bias could be demonstrated. There was no significant effect of climate trends since 1960 on observed SOC changes. SOC monitoring networks are being established in many countries. Our results demonstrate that detailed and long-term land management data are crucial to explain the observed SOC changes for such networks.

  18. PENERAPAN MODEL PEMBELAJARAN PROBLEM BASED INSTRUCTION DENGAN PENDEKATAN PREDICT-OBSERVE-EXPLAIN

    Directory of Open Access Journals (Sweden)

    Ayu Dwi Listiowati

    2015-11-01

    Full Text Available This research aimed to determine the effect of Problem Based Instruction learning model with Predict-Observe-Explain approach on chemistry learning outcomes. The population is XI grader Sciences of Senior High School in Brebes for academic year 2011/2012. Initial data analysis showed that the population are normally distributed and homogeneous, so the sampling technique which used is cluster random sampling. From this sampling, XI Science-5 used as a control class (Problem Based Instruction learning model without Predict-Observe-Explain approach and XI Science-1 as an experiment class (Problem Based Instruction with Predict Observe Explain approach. Final data analysis showed that learning outcomes for both classes are normally distributed and have equal variances. In the correlation test, obtained 0.433 of r b value, which showed a middle correlation, so Problem Based Instruction with Predict-ObserveExplain approach has middle effect on chemistry learning outcomes in solubility and solubility product. This learning contributes to student learning outcomes is 19%. The average value of affective and psychomotor in experimental class is better than the control class. Based on this  research, we can conclude that Problem Based Instruction with Predict-Observe-Explain approach has a positive effect on chemistry learning product in Senior High School students.Key Words: Problem Based Instruction Learning 

  19. Testing Stereotype Threat: Does Anxiety Explain Race and Sex Differences in Achievement?

    Science.gov (United States)

    Osborne, Jason W.

    2001-07-01

    Steele's (1992, 1997) stereotype-threat theory attempts to explain underperformance of minority students in academic domains and of women in mathematics. Steele argues that situational self-relevance of negative group stereotypes in testing situations increases the anxiety these students experience and that these differential anxiety levels explain performance differences. Research shows that manipulation of stereotype threat can affect academic performance. However, there has been little research testing whether anxiety does at least partially explain the relationship between race and achievement. The goal of this study was to examine whether anxiety will explain racial differences in academic performance and gender differences in math performance in the context of a nationally representative sample of high school seniors. Partial mediation was observed, with anxiety explaining significant portions of the racial differences in academic performance. Anxiety also partially explained sex differences in math achievement, although the effect sizes were very small. These results provide general support for Steele's stereotype-threat hypothesis. Copyright 2001 Academic Press.

  20. Do factors related to combustion-based sources explain ...

    Science.gov (United States)

    Introduction: Spatial heterogeneity of effect estimates in associations between PM2.5 and total non-accidental mortality (TNA) in the United States (US), is an issue in epidemiology. This study uses rate ratios generated from the Multi-City/Multi-Pollutant study (1999-2005) for 313 core-based statistical areas (CBSA) and their metropolitan divisions (MD) to examine combustion-based sources of heterogeneity.Methods: For CBSA/MDs, area-specific log rate ratios (betas) were derived from a model adjusting for time, an interaction with age-group, day of week, and natural splines of current temperature, current dew point, and unconstrained temperature at lags 1, 2, and 3. We assessed the heterogeneity in the betas by linear regression with inverse variance weights, using average NO2, SO2, and CO, which may act as a combustion source proxy, and these pollutants’ correlations with PM2.5. Results: We found that weighted mean PM2.5 association (0.96 percent increase in total non-accidental mortality for a 10 µg/m3 increment in PM2.5) increased by 0.26 (95% confidence interval 0.08 , 0.44) for an interquartile change (0.2) in the correlation of SO2 and PM2.5., but betas showed less dependence on the annual averages of SO2 or NO2. Spline analyses suggest departures from linearity, particularly in a model that examined correlations between PM2.5 and CO.Conclusions: We conclude that correlations between SO2 and PM2.5 as an indicator of combustion sources explains some hete

  1. Why Do Things Fall? How to Explain Why Gravity Is Not a Force

    Science.gov (United States)

    Stannard, Warren B.

    2018-01-01

    In most high school physics classes, gravity is described as an attractive force between two masses as formulated by Newton over 300 years ago. Einstein's general theory of relativity implies that gravitational effects are instead the result of a "curvature" of space-time. However, explaining why things fall without resorting to Newton's…

  2. Learning Argumentation Skills through the Use of Prompts for Self-Explaining Examples

    Science.gov (United States)

    Schworm, Silke; Renkl, Alexander

    2007-01-01

    Learning with self-explaining examples is an effective method in well-structured domains. The authors analyzed this method in teaching the complex skill of argumentation, experimentally comparing 4 conditions (N = 71 student teachers) that differed with respect to whether and how the processing of the examples was supported by self-explanation…

  3. The Role of Attitudes about Vaccine Safety, Efficacy, and Value in Explaining Parents' Reported Vaccination Behavior

    Science.gov (United States)

    LaVail, Katherine Hart; Kennedy, Allison Michelle

    2013-01-01

    Objectives: To explain vaccine confidence as it related to parents' decisions to vaccinate their children with recommended vaccines, and to develop a confidence measure to efficiently and effectively predict parents' self-reported vaccine behaviors. Method: A sample of parents with at least one child younger than 6 years ("n" = 376) was…

  4. Peers and delinquency among girls and boys: are sex differences in delinquency explained by peer factors?

    NARCIS (Netherlands)

    Weerman, F.M.; Hoeve, M.

    2012-01-01

    In this article, we investigate sex differences in the relationship between peers and delinquency. We analyse to what extent peers have different effects on delinquency among girls and boys, and to what extent sex differences in the level of delinquency can be explained by differential exposure or

  5. Explaining Non-Take-up of Water Subsidy

    Directory of Open Access Journals (Sweden)

    Momi Dahan

    2011-12-01

    Full Text Available We use two separate quasi-natural experiments to explore the relative importance of information and administrative costs in explaining non-take-up of water subsidy. The first “experiment” shows that the take-up rate of a household with lower administrative costs is not significantly different from otherwise identical households. In contrast, using the same program, the second “experiment” reveals that the take-up rate of a household that is more likely to be informed is substantially higher compared to otherwise identical households. These findings support the idea that information plays a major role in explaining non-take-up of water subsidy.

  6. Firm Performance and Comply or Explain Disclosure in Corporate Governance

    DEFF Research Database (Denmark)

    Rose, Caspar

    2016-01-01

    : complies, complies poorly, explains and explains poorly. The article demonstrates that measuring the degree of compliance cannot be done in a mechanical way. Instead, it must be customized to the respective national institutional environment, which suggests country comparisons will be difficult to make....... The article contributes to the ongoing discussion of whether firms consider soft law to be a “tick the box” exercise or, alternatively, whether firms should work seriously with the recommendations in order to professionalize and increase competences among board members. The article's findings suggest...

  7. Taxes do not explain lower public power rates

    International Nuclear Information System (INIS)

    Kelly, J.

    1993-01-01

    In 1990, approximately 7.7% of the retail revenues of public power systems flowed to state and local governments in the form of tax payments and contributions. The argument is presented that this fact contradicts the notion that retail rates of investor-owned utilities are higher than public systems because investor-owned utilities (IOU's) pay taxes and public systems do not. Many IOU's promote this motion in an attempt to explain why their retail rates are significantly higher. It is concluded that relative tax payments and contributions fail to explain public powers rate advantage over IOU's

  8. Students' Development and Use of Models to Explain Electrostatic Interactions

    Science.gov (United States)

    Mayer, Kristin Elizabeth

    The National Research Council (2012) recently published A Framework for K-12 Science Education that describes a vision for science classrooms where students engage in three dimensions--scientific and engineering practices, crosscutting concepts, and disciplinary core ideas--to explain phenomena or observations they can make about the universe around them. This vision of science instruction is a significant shift from current classroom instruction. This dissertation provides detailed examples of how students developed and used models to build causal explanations of phenomena. I co-taught classes that focused on having students develop and revise models of electric fields and atomic structure using a curriculum that was designed to align with the three-dimensional vision of learning. I developed case studies of eleven students from these classes. I analyzed the students' responses and interviewed the students throughout the school year. By comparing and contrasting the analysis across the analysis of students' interviews, I identified four themes: 1) students could apply their ideas to explain novel and abstract phenomena; 2) students struggled to connect changes in their atomic models to evidence, but ended up with dynamic models of atomic structure that they could apply to explain phenomena; 3) students developed models of atomic structure that they applied to explain phenomena, but they did not use models of electric fields in this way; and 4) too much focus on details interfered with students' ability to apply their models to explain new phenomena. This dissertation highlights the importance of focusing on phenomena in classrooms that aim at aligning with three-dimensional learning. Students struggled to focus on specific content and apply their ideas to explain phenomena at the same time. In order to apply ideas to new context, students had to shift their focus from recalling ideas to applying the ideas they do have. A focus on phenomena allowed students to show

  9. Firm Performance and Comply or Explain Disclosure in Corporate Governance

    DEFF Research Database (Denmark)

    Rose, Caspar

    2016-01-01

    : complies, complies poorly, explains and explains poorly. The article demonstrates that measuring the degree of compliance cannot be done in a mechanical way. Instead, it must be customized to the respective national institutional environment, which suggests country comparisons will be difficult to make...... that soft law may be an efficient way of increasing the quality of corporate governance among listed firms. However, in order to strengthen investor confidence, national code authorities/committees should be more active in penalizing poor explanations as well as cases where firms wrongfully state...

  10. Time delay and noise explaining the behaviour of the cell growth in fermentation process

    Energy Technology Data Exchange (ETDEWEB)

    Ayuobi, Tawfiqullah; Rosli, Norhayati [Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, Lebuhraya Tun Razak, 26300 Gambang, Pahang (Malaysia); Bahar, Arifah [Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Salleh, Madihah Md [Department of Biotechnology Industry, Faculty of Biosciences and Bioengineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia)

    2015-02-03

    This paper proposes to investigate the interplay between time delay and external noise in explaining the behaviour of the microbial growth in batch fermentation process. Time delay and noise are modelled jointly via stochastic delay differential equations (SDDEs). The typical behaviour of cell concentration in batch fermentation process under this model is investigated. Milstein scheme is applied for solving this model numerically. Simulation results illustrate the effects of time delay and external noise in explaining the lag and stationary phases, respectively for the cell growth of fermentation process.

  11. Time delay and noise explaining the behaviour of the cell growth in fermentation process

    International Nuclear Information System (INIS)

    Ayuobi, Tawfiqullah; Rosli, Norhayati; Bahar, Arifah; Salleh, Madihah Md

    2015-01-01

    This paper proposes to investigate the interplay between time delay and external noise in explaining the behaviour of the microbial growth in batch fermentation process. Time delay and noise are modelled jointly via stochastic delay differential equations (SDDEs). The typical behaviour of cell concentration in batch fermentation process under this model is investigated. Milstein scheme is applied for solving this model numerically. Simulation results illustrate the effects of time delay and external noise in explaining the lag and stationary phases, respectively for the cell growth of fermentation process

  12. Explaining Cross-Country Differences in Attitudes Towards Immigration in the EU-15

    DEFF Research Database (Denmark)

    Malchow-Møller, Nikolaj; Munch, Jakob Roland; Schroll, Sanne

    2009-01-01

    in average attitudes. A larger part can be explained by differences in perceived consequences of immigration, but the main part is still left unexplained. Apart from providing useful input for policy makers working in the area of immigration policy, this raises a number of questions for further research......In this paper, we use data from the first two rounds of the European Social Survey to analyze the extent to which differences in average attitudes towards immigration across the EU-15 countries may be explained by differences in socioeconomic characteristics and individually perceived consequences...... of immigration, using an extension of a decomposition technique developed by Fairlie (2005). We find that despite the significant effects of socioeconomic characteristics on attitudes, differences in the distributions of these characteristics can only explain a modest share of the cross-country variation...

  13. Explaining Cross-Country Differences in Attitudes towards Immigration in the EU-15

    DEFF Research Database (Denmark)

    Malchow-Møller, Nikolaj; Munch, Jakob Roland; Schroll, Sanne

    2007-01-01

    in average attitudes. A larger part can be explained by differences in perceived consequences of immigration, but the main part is still left unexplained. Apart from providing useful input for policy makers working in the area of immigration policy, this raises a number of questions for further research......In this paper, we use data from the first two rounds of the European Social Survey to analyze the extent to which differences in average attitudes towards immigration across the EU-15 countries may be explained by differences in socioeconomic characteristics and individually perceived consequences...... of immigration, using an extension of a decomposition technique developed by Fairlie (2005). We find that despite the significant effects of socioeconomic characteristics on attitudes, differences in the distributions of these characteristics can only explain a modest share of the cross-country variation...

  14. Teaching children with autism to explain how: A case for problem solving?

    Science.gov (United States)

    Frampton, Sarah E; Alice Shillingsburg, M

    2018-04-01

    Few studies have applied Skinner's (1953) conceptualization of problem solving to teach socially significant behaviors to individuals with developmental disabilities. The current study used a multiple probe design across behavior (sets) to evaluate the effects of problem-solving strategy training (PSST) on the target behavior of explaining how to complete familiar activities. During baseline, none of the three participants with autism spectrum disorder (ASD) could respond to the problems presented to them (i.e., explain how to do the activities). Tact training of the actions in each activity alone was ineffective; however, all participants demonstrated independent explaining-how following PSST. Further, following PSST with Set 1, tact training alone was sufficient for at least one scenario in sets 2 and 3 for all 3 participants. Results have implications for generative responding for individuals with ASD and further the discussion regarding the role of problem solving in complex verbal behavior. © 2018 Society for the Experimental Analysis of Behavior.

  15. Towards explaining the speed of k-means

    NARCIS (Netherlands)

    Manthey, Bodo; van de Pol, Jan Cornelis; Raamsdonk, F.; Stoelinga, Mariëlle Ida Antoinette

    2011-01-01

    The $k$-means method is a popular algorithm for clustering, known for its speed in practice. This stands in contrast to its exponential worst-case running-time. To explain the speed of the $k$-means method, a smoothed analysis has been conducted. We sketch this smoothed analysis and a generalization

  16. Explaining residential moving intentions : the case of highway locations

    NARCIS (Netherlands)

    Hamersma, Marije; Heinen, Eva; Tillema, Taede; Arts, Jos

    2013-01-01

    In this paper Structural Equation Modeling is used to test a theoretical framework to explain the impact of highway externalities (i.e. accessibility and nuisance) on moving intentions of people living close to highways. We aimed to study whether highway externalities (alongside other contextual

  17. Design of an explainable machine learning challenge for video interviews

    NARCIS (Netherlands)

    Escalante, H.J.; Guyon, I.; Escalera, S.; Jacques, J.; Madadi, M.; Baró , X.; Ayache, S.; Viegas, E.; Gü ç lü tü rk, Y.; Gü ç lü , U.; Gerven, M.A.J. van; Lier, R.J. van

    2017-01-01

    This paper reviews and discusses research advances on "explainable machine learning" in computer vision. We focus on a particular area of the "Looking at People" (LAP) thematic domain: first impressions and personality analysis. Our aim is to make the computational intelligence and computer vision

  18. Explaining Global Women's Empowerment Using Geographic Inquiry

    Science.gov (United States)

    Grubbs, Melanie R.

    2018-01-01

    It is difficult for students who are just being introduced to major geographical concepts to understand how relatively free countries like India or Mali can have such high levels of human rights abuses as child brides, dowry deaths, and domestic violence. Textbooks explain it and video clips show examples, but it still seems surreal to teenagers…

  19. The Role of Secondary Education in Explaining Competitiveness

    Science.gov (United States)

    Baumann, Chris; Winzar, Hume

    2016-01-01

    The literature establishes that education drives economic performance, but the extent that education is associated with a country's competitiveness is empirically untested. Our study analyses Programme for International Student Assessment (PISA) data from 63 countries to ascertain education's role in explaining the competitiveness of a country.…

  20. Does Interest rate Exposure explain the Low-Volatility Anomaly?

    NARCIS (Netherlands)

    Driessen, Joost; Kuiper, Ivo; Beilo, R.

    We show that part of the outperformance of low-volatility stocks can be explained by a premium for interest rate exposure. Low-volatility stock portfolios have negative exposure to interest rates, whereas the more volatile stocks have positive exposure. Incorporating an interest rate premium

  1. Explaining Tevatron leptons photons missing- T events with ...

    Indian Academy of Sciences (India)

    (/ET) signal 3σ in excess of the standard model prediction in Tevatron Run I data. The excess can be explained by the resonant production of a smuon, which subsequently decays to a muon, a photon and a gravitino. Here, we perform combined fits of this model to the CDF 7l/ET excess, the D0 measurement of the same ...

  2. Which Mechanisms Explain Monetary Returns to International Student Mobility?

    Science.gov (United States)

    Kratz, Fabian; Netz, Nicolai

    2018-01-01

    The authors develop a conceptual framework explaining monetary returns to international student mobility (ISM). Based on data from two German graduate panel surveys, they test this framework using growth curve models and Oaxaca-Blinder decompositions. The results indicate that ISM-experienced graduates enjoy a steeper wage growth after graduation…

  3. Wealth, wages and wedlock : Explaining the college gender gap reversal

    NARCIS (Netherlands)

    Reijnders, Laurie

    2018-01-01

    We study the role of changes in the wage structure and expectations about marriage in explaining the college gender gap reversal. With strongly diminishing marginal utility of wealth and in the presence of a gender wage gap, single women have a greater incentive than single men to invest in

  4. Explaining differences between hospitals in number of organ donors

    NARCIS (Netherlands)

    Friele, R. D.; Coppen, R.; Marquet, R. L.; Gevers, J. K. M.

    2006-01-01

    The shortage of donor organs calls for a careful examination of all improvement options. In this study, 80 Dutch hospitals were compared. They provided 868 donors in a 5-year period, constituting 91% of all donors in that period in The Netherlands. Multilevel regression analysis was used to explain

  5. Recognizing, explaining and countering norm transgressive behaviour on social media

    NARCIS (Netherlands)

    Padje, E.D.H.

    2016-01-01

    In this thesis, it is researched how norm transgressive behaviour exhibited on the Dutch domains of social media can be recognized, explained and countered. An analysis of four comment threads is conducted, of which the comments can be found on the Facebook pages of three Dutch news sites and on a

  6. Explaining Tevatron leptons photons missing- T events with ...

    Indian Academy of Sciences (India)

    events with supersymmetry. B C ALLANACH. LAPTH, 9 Chemin de Bellevue, BP 110, 74941 Annecy-le-Vieux, France. Abstract. The CDF experiment reported a lepton photon missing transverse energy. (/ET) signal 3σ in excess of the standard model prediction in Tevatron Run I data. The excess can be explained by the ...

  7. Do occupational demands explain the educational gradient in health?

    NARCIS (Netherlands)

    Meyer, S.C.; Künn-Nelen, A.C.

    2014-01-01

    The aim of this paper is to investigate to what extent occupation-specific demands explain the relationship between education and health. We concentrate on ergonomic, environmental, psychical, social and time demands. Merging the German Microcensus 2009 data with a dataset including detailed

  8. Countries start to explain how their climate contributions are fair

    NARCIS (Netherlands)

    Winkler, Harald; Höhne, Niklas; Cunliffe, Guy; Kuramochi, Takeshi; April, Amanda; Villafranca Casas, de Maria Jose

    2018-01-01

    In the lead-up to the Paris Agreement, every country was invited to submit an intended nationally determined contribution (INDC), and indicate how it is fair. We analyse how countries have explained the equity of mitigation and adaptation in 163 INDCs, providing a bottom-up analysis of equity to

  9. Students Explaining Science—Assessment of Science Communication Competence

    Science.gov (United States)

    Kulgemeyer, Christoph; Schecker, Horst

    2013-12-01

    Science communication competence (SCC) is an important educational goal in the school science curricula of several countries. However, there is a lack of research about the structure and the assessment of SCC. This paper specifies the theoretical framework of SCC by a competence model. We developed a qualitative assessment method for SCC that is based on an expert-novice dialog: an older student (explainer, expert) explains a physics phenomenon to a younger peer (addressee, novice) in a controlled test setting. The explanations are video-recorded and analysed by qualitative content analysis. The method was applied in a study with 46 secondary school students as explainers. Our aims were (a) to evaluate whether our model covers the relevant features of SCC, (b) to validate the assessment method and (c) to find characteristics of addressee-adequate explanations. A performance index was calculated to quantify the explainers' levels of competence on an ordinal scale. We present qualitative and quantitative evidence that the index is adequate for assessment purposes. It correlates with results from a written SCC test and a perspective taking test (convergent validity). Addressee-adequate explanations can be characterized by use of graphical representations and deliberate switches between scientific and everyday language.

  10. Explaining Choice and Share of Category Requirements of Biologic Meat

    NARCIS (Netherlands)

    P.C. Verhoef (Peter); K. Vlagsma-Brangule (Kristine)

    2003-01-01

    textabstractIn this paper we examine factors determining choice and consumption of biologic or organic meat. In our model explaining choice and share of category requirements, we consider economic/marketing variables (quality, price, and distribution), emotions (fear, empathy, andguilt), social

  11. A Conceptual Characterization of Online Videos Explaining Natural Selection

    Science.gov (United States)

    Bohlin, Gustav; Göransson, Andreas; Höst, Gunnar E.; Tibell, Lena A. E.

    2017-01-01

    Educational videos on the Internet comprise a vast and highly diverse source of information. Online search engines facilitate access to numerous videos claiming to explain natural selection, but little is known about the degree to which the video content match key evolutionary content identified as important in evolution education research. In…

  12. Use of environmental parameters to explain the variability in ...

    African Journals Online (AJOL)

    This study attempts to explain the variability in recruitment of sardine in the northern Benguela and to develop potential models by including environmental information to predict recruitment. Two different recruitment and spawner number datasets were available: a VPA-developed dataset, for the period 1952–1987, and ...

  13. Juvenile Delinquency Explained? A Test of Containment Theory.

    Science.gov (United States)

    Thompson, William E.; Dodder, Richard A.

    1983-01-01

    Examines the extent to which variation in self-reported delinquency is explained by the seven containment variables (favorable self-concept, goal orientation, frustration tolerance, retention of norms, internalization of rules, availability of meaningful roles, and group reinforcement), and focuses on racial and sex differences in self-reported…

  14. Teachers mathematical communication profile in explaining subject matter

    Science.gov (United States)

    Umami, Rohmatul; Budayasa, I. Ketut; Suwarsono, St.

    2017-12-01

    This study aimed to see a teachers mathematical communication profile in explaining a subject matter. It is a qualitative research. A high-school junior teacher (i.e., a teacher with 1- to 5-year experience) teaching mathematics at X-Social Class was selected as the subject of this study. The data was collected by observing the teachers mathematical communication in explaining a given material (i.e., the rule of sine) in class and an in-depth interview would be organized respectively. The result showed that the junior teacher explained the subject matter in systematic, complete, fluent, and centered manner. In this case, she began with reminding students on the previous material related to the current material to be learned, informing the current learning objectives, and finally delivering the subject matter. To support her explanation, the teacher also provided some related information, led the students attention into the given material by asking them particular related questions, and did not use any confusing terms. However, the study found that some of high-school teachers still used less appropriate language in explaining materials.

  15. Explaining excess morbidity amongst homeless shelter users: A multivariate analysis for the Danish adult population.

    Science.gov (United States)

    Benjaminsen, Lars; Birkelund, Jesper Fels

    2018-03-01

    This article analyses excess morbidity amongst homeless shelter users compared to the general Danish population. The study provides an extensive control for confounding and investigates to what extent excess morbidity is explained by homelessness or other risk factors. Data set includes administrative micro-data for 4,068,926 Danes who were 23 years or older on 1 January 2007. Nationwide data on shelter use identified 14,730 individuals as shelter users from 2002 to 2006. Somatic diseases were measured from 2007 to 2011 through diagnosis data from hospital discharges. The risk of somatic diseases amongst shelter users was analysed through a multivariate model that decomposed the total effect into a direct effect and indirect effects mediated by other risk factors. The excess morbidity associated with shelter use is substantially lower than in studies that did not include an extensive control. Approximately 80% of excess morbidity amongst shelter users is attributed to other risk factors. A large part of the excess morbidity is explained by substance abuse problems and lack of employment, whilst mental illness, low income, low education, civil status and ethnic minority background explain only a limited part. However, when conducting an extensive control for confounding, a significantly higher morbidity was identified amongst shelter users for infectious diseases, lung, skin, blood and digestive diseases, injuries, and poisoning. Ill health amongst homeless shelter users is widely explained by substance abuse problems and other risk factors. Nonetheless, for many diseases homelessness poses an additional risk to the health.

  16. Explaining Support Vector Machines: A Color Based Nomogram.

    Directory of Open Access Journals (Sweden)

    Vanya Van Belle

    Full Text Available Support vector machines (SVMs are very popular tools for classification, regression and other problems. Due to the large choice of kernels they can be applied with, a large variety of data can be analysed using these tools. Machine learning thanks its popularity to the good performance of the resulting models. However, interpreting the models is far from obvious, especially when non-linear kernels are used. Hence, the methods are used as black boxes. As a consequence, the use of SVMs is less supported in areas where interpretability is important and where people are held responsible for the decisions made by models.In this work, we investigate whether SVMs using linear, polynomial and RBF kernels can be explained such that interpretations for model-based decisions can be provided. We further indicate when SVMs can be explained and in which situations interpretation of SVMs is (hitherto not possible. Here, explainability is defined as the ability to produce the final decision based on a sum of contributions which depend on one single or at most two input variables.Our experiments on simulated and real-life data show that explainability of an SVM depends on the chosen parameter values (degree of polynomial kernel, width of RBF kernel and regularization constant. When several combinations of parameter values yield the same cross-validation performance, combinations with a lower polynomial degree or a larger kernel width have a higher chance of being explainable.This work summarizes SVM classifiers obtained with linear, polynomial and RBF kernels in a single plot. Linear and polynomial kernels up to the second degree are represented exactly. For other kernels an indication of the reliability of the approximation is presented. The complete methodology is available as an R package and two apps and a movie are provided to illustrate the possibilities offered by the method.

  17. Explaining Compound Generalization in Associative and Causal Learning Through Rational Principles of Dimensional Generalization

    Science.gov (United States)

    Soto, Fabian A.; Gershman, Samuel J.; Niv, Yael

    2014-01-01

    How do we apply learning from one situation to a similar, but not identical, situation? The principles governing the extent to which animals and humans generalize what they have learned about certain stimuli to novel compounds containing those stimuli vary depending on a number of factors. Perhaps the best studied among these factors is the type of stimuli used to generate compounds. One prominent hypothesis is that different generalization principles apply depending on whether the stimuli in a compound are similar or dissimilar to each other. However, the results of many experiments cannot be explained by this hypothesis. Here we propose a rational Bayesian theory of compound generalization that uses the notion of consequential regions, first developed in the context of rational theories of multidimensional generalization, to explain the effects of stimulus factors on compound generalization. The model explains a large number of results from the compound generalization literature, including the influence of stimulus modality and spatial contiguity on the summation effect, the lack of influence of stimulus factors on summation with a recovered inhibitor, the effect of spatial position of stimuli on the blocking effect, the asymmetrical generalization decrement in overshadowing and external inhibition, and the conditions leading to a reliable external inhibition effect. By integrating rational theories of compound and dimensional generalization, our model provides the first comprehensive computational account of the effects of stimulus factors on compound generalization, including spatial and temporal contiguity between components, which have posed longstanding problems for rational theories of associative and causal learning. PMID:25090430

  18. A mechanism-based pharmacokinetic model of fenofibrate for explaining increased drug absorption after food consumption.

    Science.gov (United States)

    Back, Hyun-Moon; Song, Byungjeong; Pradhan, Sudeep; Chae, Jung-Woo; Han, Nayoung; Kang, Wonku; Chang, Min Jung; Zheng, Jiao; Kwon, Kwang-Il; Karlsson, Mats O; Yun, Hwi-Yeol

    2018-01-25

    Oral administration of drugs is convenient and shows good compliance but it can be affected by many factors in the gastrointestinal (GI) system. Consumption of food is one of the major factors affecting the GI system and consequently the absorption of drugs. The aim of this study was to develop a mechanistic GI absorption model for explaining the effect of food on fenofibrate pharmacokinetics (PK), focusing on the food type and calorie content. Clinical data from a fenofibrate PK study involving three different conditions (fasting, standard meals and high-fat meals) were used. The model was developed by nonlinear mixed effect modeling method. Both linear and nonlinear effects were evaluated to explain the impact of food intake on drug absorption. Similarly, to explain changes in gastric emptying time for the drug due to food effects was evaluated. The gastric emptying rate increased by 61.7% during the first 6.94 h after food consumption. Increased calories in the duodenum increased the absorption rate constant of the drug in fed conditions (standard meal = 16.5%, high-fat meal = 21.8%) compared with fasted condition. The final model displayed good prediction power and precision. A mechanistic GI absorption model for quantitatively evaluating the effects of food on fenofibrate absorption was successfully developed, and acceptable parameters were obtained. The mechanism-based PK model of fenofibrate can quantify the effects of food on drug absorption by food type and calorie content.

  19. Disentangling vegetation diversity from climate–energy and habitat heterogeneity for explaining animal geographic patterns

    Science.gov (United States)

    Jimenez-Alfaro, Borja; Chytry, Milan; Mucina, Ladislav; Grace, James B.; Rejmanek, Marcel

    2016-01-01

    Broad-scale animal diversity patterns have been traditionally explained by hypotheses focused on climate–energy and habitat heterogeneity, without considering the direct influence of vegetation structure and composition. However, integrating these factors when considering plant–animal correlates still poses a major challenge because plant communities are controlled by abiotic factors that may, at the same time, influence animal distributions. By testing whether the number and variation of plant community types in Europe explain country-level diversity in six animal groups, we propose a conceptual framework in which vegetation diversity represents a bridge between abiotic factors and animal diversity. We show that vegetation diversity explains variation in animal richness not accounted for by altitudinal range or potential evapotranspiration, being the best predictor for butterflies, beetles, and amphibians. Moreover, the dissimilarity of plant community types explains the highest proportion of variation in animal assemblages across the studied regions, an effect that outperforms the effect of climate and their shared contribution with pure spatial variation. Our results at the country level suggest that vegetation diversity, as estimated from broad-scale classifications of plant communities, may contribute to our understanding of animal richness and may be disentangled, at least to a degree, from climate–energy and abiotic habitat heterogeneity.

  20. Why is the sunny side always up? Explaining the spatial mapping of concepts by language use.

    Science.gov (United States)

    Goodhew, Stephanie C; McGaw, Bethany; Kidd, Evan

    2014-10-01

    Humans appear to rely on spatial mappings to represent and describe concepts. The conceptual cuing effect describes the tendency for participants to orient attention to a spatial location following the presentation of an unrelated cue word (e.g., orienting attention upward after reading the word sky). To date, such effects have predominately been explained within the embodied cognition framework, according to which people's attention is oriented on the basis of prior experience (e.g., sky → up via perceptual simulation). However, this does not provide a compelling explanation for how abstract words have the same ability to orient attention. Why, for example, does dream also orient attention upward? We report on an experiment that investigated the role of language use (specifically, collocation between concept words and spatial words for up and down dimensions) and found that it predicted the cuing effect. The results suggest that language usage patterns may be instrumental in explaining conceptual cuing.

  1. Main features of narrow sociological theories explaining mental disorders

    Directory of Open Access Journals (Sweden)

    Opalić Petar

    2006-01-01

    Full Text Available In the introduction, the author states that sociological theories explaining mental disorders in the narrow sense have originated as an opposition to medical, i.e. biological model of interpreting mental disorders. With regard to this, the following sociological theories explaining mental disorders are presented in more detail: theory of anomie by Durkheim and Merton (with Merton’s typology of deviant behavior, social roles theory by Parsons, labeling theory by Scheff and other authors, theoretical career model of the mentally ill, the concept of psychic disorder of etnomethodology and finally, the anti-psychiatric interpretation of mental disorders. It is concluded that, although historically older, sociological theories of the onset of mental disorders are filling the epistemological void that occurred in understanding the role of society on the whole and a series of social factors particularly on the different aspects of understanding mental disorders.

  2. How Much of Language Acquisition Does Operant Conditioning Explain?

    Directory of Open Access Journals (Sweden)

    Christopher B. Sturdy

    2017-10-01

    Full Text Available Since the 1950s, when Chomsky argued that Skinner’s arguments could not explain syntactic acquisition, psychologists have generally avoided explicitly invoking operant or instrumental conditioning as a learning mechanism for language among human children. In this article, we argue that this is a mistake. We focus on research that has been done on language learning in human infants and toddlers in order to illustrate our points. Researchers have ended up inventing learning mechanisms that, in actual practice, not only resemble but also in fact are examples of operant conditioning (OC by any other name they select. We argue that language acquisition researchers should proceed by first ruling out OC before invoking alternative learning mechanisms. While it is possible that OC cannot explain all of the language acquisition, simple learning mechanisms that work across species may have some explanatory power in children’s language learning.

  3. Imitation explains the propagation, not the stability of animal culture.

    Science.gov (United States)

    Claidière, Nicolas; Sperber, Dan

    2010-02-22

    For acquired behaviour to count as cultural, two conditions must be met: it must propagate in a social group, and it must remain stable across generations in the process of propagation. It is commonly assumed that imitation is the mechanism that explains both the spread of animal culture and its stability. We review the literature on transmission chain studies in chimpanzees (Pan troglodytes) and other animals, and we use a formal model to argue that imitation, which may well play a major role in the propagation of animal culture, cannot be considered faithful enough to explain its stability. We consider the contribution that other psychological and ecological factors might make to the stability of animal culture observed in the wild.

  4. How Much of Language Acquisition Does Operant Conditioning Explain?

    Science.gov (United States)

    Sturdy, Christopher B.; Nicoladis, Elena

    2017-01-01

    Since the 1950s, when Chomsky argued that Skinner’s arguments could not explain syntactic acquisition, psychologists have generally avoided explicitly invoking operant or instrumental conditioning as a learning mechanism for language among human children. In this article, we argue that this is a mistake. We focus on research that has been done on language learning in human infants and toddlers in order to illustrate our points. Researchers have ended up inventing learning mechanisms that, in actual practice, not only resemble but also in fact are examples of operant conditioning (OC) by any other name they select. We argue that language acquisition researchers should proceed by first ruling out OC before invoking alternative learning mechanisms. While it is possible that OC cannot explain all of the language acquisition, simple learning mechanisms that work across species may have some explanatory power in children’s language learning. PMID:29163295

  5. Explaining labor wedge trends: An equilibrium search approach

    Directory of Open Access Journals (Sweden)

    Coralia A. Quintero Rojas

    2016-06-01

    Full Text Available In this paper, we present a search and matching model of the labor market and use this as a device to explain the long-run variation in the aggregate hours worked in several OECD countries over the period 1980-2013. The model distinguishes between hours worked per employee (intensive margin and the employment rate (extensive margin and includes a tax/benefit system. This allows us to assess the impact of the observed time-varying heterogeneity of taxes, unemployment benefits, and workers’ bargaining power on the two margins. Our method is based on an accounting procedure. Once it has been calibrated, we find that, for the ten countries of the sample, our search economy is able to explain the patterns of the two margins of aggregate hours worked over the 1980-2013 period, when it includes the cross-country heterogeneity of the labor market institutions.

  6. How Much of Language Acquisition Does Operant Conditioning Explain?

    Science.gov (United States)

    Sturdy, Christopher B; Nicoladis, Elena

    2017-01-01

    Since the 1950s, when Chomsky argued that Skinner's arguments could not explain syntactic acquisition, psychologists have generally avoided explicitly invoking operant or instrumental conditioning as a learning mechanism for language among human children. In this article, we argue that this is a mistake. We focus on research that has been done on language learning in human infants and toddlers in order to illustrate our points. Researchers have ended up inventing learning mechanisms that, in actual practice, not only resemble but also in fact are examples of operant conditioning (OC) by any other name they select. We argue that language acquisition researchers should proceed by first ruling out OC before invoking alternative learning mechanisms. While it is possible that OC cannot explain all of the language acquisition, simple learning mechanisms that work across species may have some explanatory power in children's language learning.

  7. A developmental hypothesis to explain the multicentricity of breast cancer

    OpenAIRE

    Sharpe, C R

    1998-01-01

    In this article the author proposes that the multicentricity of breast cancer might be explained by a developmental hypothesis. Genetic alterations ("hits") occurring in epithelial stem cells during the development of the breast may be transmitted to populations of daughter cells during growth. As a result, areas of the breast may be predisposed to malignant transformation with the occurrence of further genetic hits. Areas with the same predisposition should be anatomically connected, and ear...

  8. Do mirror neurons explain misattribution of emotions in music?

    Science.gov (United States)

    Gridley, Mark C; Hoff, Robert

    2006-04-01

    It is speculated that certain listeners' misattribution of anger in the music of avant garde jazz saxophonists could be explained by the activity of mirror neurons. There is a neurological basis for the human tendency to imitate what is perceived in another person. This may lead to an inference that whatever comparable activity would be required to achieve a similar condition in the imitator is the condition being experienced by the person being imitated.

  9. Glacial ocean circulation and stratification explained by reduced atmospheric temperature

    OpenAIRE

    Jansen, Malte F.

    2016-01-01

    To understand climatic swings between glacial and interglacial climates we need to explain the observed fluctuations in atmospheric carbon dioxide (CO2), which in turn are most likely driven by changes in the deep ocean circulation. This study presents a model for differences in the deep ocean circulation between glacial and interglacial climates consistent with both our physical understanding and various proxy observations. The results suggest that observed changes in ocean circulation and s...

  10. Explaining the consolidation of financial statementsin the Swiss Federal Government

    OpenAIRE

    Argento, Daniela; Grossi, Giuseppe; Vollenweider, Petra

    2012-01-01

    The growing development of decentralized entities has highlighted the limitations f the traditional annual reports of governments, which do not necessarily capture he financial consequences of subsidiaries, joint ventures and associates. There s a growing tendency to consider consolidated financial statements as essential o support decision-making processes and to ensure higher public accountability. his paper seeks to understand and to explain how the Swiss Federal Government as prepared its...

  11. How Much of Language Acquisition Does Operant Conditioning Explain?

    OpenAIRE

    Sturdy, Christopher B.; Nicoladis, Elena

    2017-01-01

    Since the 1950s, when Chomsky argued that Skinner’s arguments could not explain syntactic acquisition, psychologists have generally avoided explicitly invoking operant or instrumental conditioning as a learning mechanism for language among human children. In this article, we argue that this is a mistake. We focus on research that has been done on language learning in human infants and toddlers in order to illustrate our points. Researchers have ended up inventing learning mechanisms that, in ...

  12. Who Asks For Voter Identification? Explaining Poll-Worker Discretion

    OpenAIRE

    Atkeson, Lonna Rae; Kerevel, Yann P.; Alvarez, R. Michael; Hall, Thad E.

    2014-01-01

    As street-level bureaucrats, poll workers bear the primary responsibility for implementing voter identification requirements. Voter identification requirements are not implemented equally across groups of voters, and poll workers exercise substantial discretion in how they apply election law. In states with minimal and varying identification requirements, poll workers appear to treat especially minority voters differently, requesting more stringent voter identification. We explain why poll wo...

  13. How brain and neuronal networks explain human reality

    Directory of Open Access Journals (Sweden)

    Javier Monserrat

    2017-02-01

    Full Text Available How is human reality presented to us in phenomenological experience? It is the one we see daily in our personal and social life. We are made of matter, we are part of the evolutionary universe. In addition, a psychic life is formed in us: sensation, a system of perceptions, an integrated consciousness, a condition of psychological subject; We produce knowledge, emotions, motivations; But, above all, we have a mind that rationally moves and installs us into a world of human emotions; This emotional reason lies at the base of the search for the truth of the universe, the meaning of life and the moral responsibility, in personal and social life. Our human reality is, therefore, a personal reality. We are persons. Now, how does science, neurology, explain today the fact that our human reality possesses these properties that give us the personal condition? This should be able to be explained (this is the initial assumption from the physical-biological world. Now, in particular, how does science make it possible to explain that evolution has produced us in our condition of ratio-emotional persons? That is, what is the physical support that makes intelligible the psycho-bio-physical ontology that evolutionarily produces our personal phenomenological experience? This is, ultimately, still the fundamental question of human sciences. What science, namely neurology, must explain (that is, know the causes that have produced it is obvious: the fact of our sensibility-consciousness, our condition of psychic subjects, knowledge and emotional reason that have emerged in the universe; In such a way that, once the emotional reason emerges, it leads by itself to constitute the rational activity and the emotions of the human person aimed at building the meaning of his life. These are the issues we address in this article.

  14. Explaining Cost Efficiency of Scottish Farms: A Stochastic Frontier Analysis

    OpenAIRE

    Revoredo-Giha, Cesar; Milne, Catherine E.; Leat, Philip M.K.; Cho, Woong Je

    2006-01-01

    In this paper the cost efficiency of Scottish farms is determined, variables that explain the relative cost efficiency by farm type are identified and implications discussed. A cost efficiency approach was selected as it can deal with farms producing multiple outputs (in contrast to production frontiers), and second because it can accommodate output constraints imposed by the Common Agricultural Policy (CAP). To estimate the stochastic cost frontier, a generalised multi-product translog cost ...

  15. Explaining China’s Evolving Policy on UN Peacekeeping

    Science.gov (United States)

    2017-06-01

    of Force, 85. 20 As some states have multiple ethnic groups, an ethnic conflict across the border can drag the government into a response as it...NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS Approved for public release. Distribution is unlimited. EXPLAINING...PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Postgraduate School Monterey, CA 93943-5000 8. PERFORMING ORGANIZATION REPORT NUMBER 9

  16. Buzz Factor or Innovation Potential: What Explains Cryptocurrencies? Returns?

    OpenAIRE

    Wang, Sha; Vergne, Jean-Philippe

    2017-01-01

    Cryptocurrencies have become increasingly popular since the introduction of bitcoin in 2009. In this paper, we identify factors associated with variations in cryptocurrencies' market values. In the past, researchers argued that the "buzz" surrounding cryptocurrencies in online media explained their price variations. But this observation obfuscates the notion that cryptocurrencies, unlike fiat currencies, are technologies entailing a true innovation potential. By using, for the first time, a u...

  17. Factors explaining variance in perceived pain in women with fibromyalgia

    Directory of Open Access Journals (Sweden)

    Lund Anders

    2002-04-01

    Full Text Available Abstract Background We hypothesized that a substantial proportion of the subjectively experienced variance in pain in fibromyalgia patients would be explained by psychological factors alone, but that a combined model, including neuroendocrine and autonomic factors, would give the most parsimonious explanation of variance in pain. Methods Psychometric assessment included McGill Pain Questionnaire, General Health Questionnaire, Hospital Anxiety and Depression Rating Scale, Eysenck personality Inventory, Neuroticism and Lie subscales, Toronto Alexithymia Scale, and Multidimensional Health Locus of Control Scale and was performed in 42 female patients with fibromyalgia and 48 female age matched random sample population controls. A subgroup of the original sample (22 fibromyalgia patients and 13 controls underwent a pharmacological challenge test with buspirone to assess autonomic and adrenocortical reactivity to serotonergic challenge. Results Although fibromyalgia patients scored high on neuroticism, anxiety, depression and general distress, only a minor part of variance in pain was explained by psychological factors alone. High pain score was associated with high neuroticism, low baseline cortisol level and small drop in systolic blood pressure after buspirone challenge test. This model explained 41.5% of total pain in fibromyalgia patients. In population controls, psychological factors alone were significant predictors for variance in pain. Conclusion Fibromyalgia patients may have reduced reactivity in the central sympathetic system or perturbations in the sympathetic-parasympathetic balance. This study shows that a biopsychosocial model, including psychological factors as well as factors related to perturbations of the autonomic nervous system and hypothalamic-pituitary-adrenal axis, is needed to explain perceived pain in fibromyalgia patients.

  18. Factors explaining variance in perceived pain in women with fibromyalgia

    OpenAIRE

    Malt, Eva Albertsen; Olafsson, Snorri; Lund, Anders; Ursin, Holger

    2002-01-01

    Abstract Background We hypothesized that a substantial proportion of the subjectively experienced variance in pain in fibromyalgia patients would be explained by psychological factors alone, but that a combined model, including neuroendocrine and autonomic factors, would give the most parsimonious explanation of variance in pain. Methods Psychometric assessment included McGill Pain Questionnaire, General Health Questionnaire, Hospital Anxiety and Depression Rating Scale, Eysenck personality I...

  19. Explaining ecological clusters of maternal depression in South Western Sydney

    Science.gov (United States)

    2014-01-01

    Background The aim of the qualitative study reported here was to: 1) explain the observed clustering of postnatal depressive symptoms in South Western Sydney; and 2) identify group-level mechanisms that would add to our understanding of the social determinants of maternal depression. Methods Critical realism provided the methodological underpinning for the study. The setting was four local government areas in South Western Sydney, Australia. Child and Family practitioners and mothers in naturally occurring mothers groups were interviewed. Results Using an open coding approach to maximise emergence of patterns and relationships we have identified seven theoretical concepts that might explain the observed spatial clustering of maternal depression. The theoretical concepts identified were: Community-level social networks; Social Capital and Social Cohesion; "Depressed community"; Access to services at the group level; Ethnic segregation and diversity; Supportive social policy; and Big business. Conclusions We postulate that these regional structural, economic, social and cultural mechanisms partially explain the pattern of maternal depression observed in families and communities within South Western Sydney. We further observe that powerful global economic and political forces are having an impact on the local situation. The challenge for policy and practice is to support mothers and their families within this adverse regional and global-economic context. PMID:24460690

  20. Explaining ecological clusters of maternal depression in South Western Sydney.

    Science.gov (United States)

    Eastwood ED, John; Kemp, Lynn; Jalaludin, Bin

    2014-01-24

    The aim of the qualitative study reported here was to: 1) explain the observed clustering of postnatal depressive symptoms in South Western Sydney; and 2) identify group-level mechanisms that would add to our understanding of the social determinants of maternal depression. Critical realism provided the methodological underpinning for the study. The setting was four local government areas in South Western Sydney, Australia. Child and Family practitioners and mothers in naturally occurring mothers groups were interviewed. Using an open coding approach to maximise emergence of patterns and relationships we have identified seven theoretical concepts that might explain the observed spatial clustering of maternal depression. The theoretical concepts identified were: Community-level social networks; Social Capital and Social Cohesion; "Depressed community"; Access to services at the group level; Ethnic segregation and diversity; Supportive social policy; and Big business. We postulate that these regional structural, economic, social and cultural mechanisms partially explain the pattern of maternal depression observed in families and communities within South Western Sydney. We further observe that powerful global economic and political forces are having an impact on the local situation. The challenge for policy and practice is to support mothers and their families within this adverse regional and global-economic context.

  1. Psychological flexibility and mindfulness explain intuitive eating in overweight adults.

    Science.gov (United States)

    Sairanen, Essi; Tolvanen, Asko; Karhunen, Leila; Kolehmainen, Marjukka; Järvelä, Elina; Rantala, Sanni; Peuhkuri, Katri; Korpela, Riitta; Lappalainen, Raimo

    2015-07-01

    The current study investigated whether mindfulness and psychological flexibility, independently and together, explain intuitive eating. The participants were overweight or obese persons (N = 306) reporting symptoms of perceived stress and enrolled in a psychological lifestyle intervention study. Participants completed self-report measures of psychological flexibility; mindfulness including the subscales observe, describe, act with awareness, non-react, and non-judgment; and intuitive eating including the subscales unconditional permission to eat, eating for physical reasons, and reliance on hunger/satiety cues. Psychological flexibility and mindfulness were positively associated with intuitive eating factors. The results suggest that mindfulness and psychological flexibility are related constructs that not only account for some of the same variance in intuitive eating, but they also account for significant unique variances in intuitive eating. The present results indicate that non-judgment can explain the relationship between general psychological flexibility and unconditional permission to eat as well as eating for physical reasons. However, mindfulness skills-acting with awareness, observing, and non-reacting-explained reliance on hunger/satiety cues independently from general psychological flexibility. These findings suggest that mindfulness and psychological flexibility are interrelated but not redundant constructs and that both may be important for understanding regulation processes underlying eating behavior. © The Author(s) 2015.

  2. Explaining the Early Development and Health of Teen Mothers’ Children*

    Science.gov (United States)

    Mollborn, Stefanie; Dennis, Jeff A.

    2013-01-01

    The transmission of social disadvantage from teenage mothers to their children is well established, but when and why do these disparities emerge in the early life course? Using nationally representative data from the Early Childhood Longitudinal Study-Birth Cohort, this study investigated the relationship between teen childbearing and children’s cognition, behavior, and health from infancy through preschool. Developmental disparities between teenage mothers’ children and others were largely nonexistent at 9 months but accumulated with age. Having a teenage mother predicted compromised development across several domains by age 4½. Our conceptual model expected preexisting disadvantage, ongoing resource disadvantage, and compromised parenting quality to explain the association between teen childbearing and child outcomes. Preexisting social disadvantage accounted for much of this relationship. Financial, social, and material resources in the child’s household partially or fully explained each of the remaining significant relationships between teenage childbearing and child outcomes. Parenting quality explained a smaller proportion of these relationships than did resources, and these factors’ influences were largely independent. Because children of teenage mothers with a modest set of resources were not predicted to have compromised development, resources provided in early childhood may have the potential to reduce developmental disparities for teenage mothers’ children. PMID:23630407

  3. Explaining the Early Development and Health of Teen Mothers' Children.

    Science.gov (United States)

    Mollborn, Stefanie; Dennis, Jeff A

    2012-12-01

    The transmission of social disadvantage from teenage mothers to their children is well established, but when and why do these disparities emerge in the early life course? Using nationally representative data from the Early Childhood Longitudinal Study-Birth Cohort, this study investigated the relationship between teen childbearing and children's cognition, behavior, and health from infancy through preschool. Developmental disparities between teenage mothers' children and others were largely nonexistent at 9 months but accumulated with age. Having a teenage mother predicted compromised development across several domains by age 4½. Our conceptual model expected preexisting disadvantage, ongoing resource disadvantage, and compromised parenting quality to explain the association between teen childbearing and child outcomes. Preexisting social disadvantage accounted for much of this relationship. Financial, social, and material resources in the child's household partially or fully explained each of the remaining significant relationships between teenage childbearing and child outcomes. Parenting quality explained a smaller proportion of these relationships than did resources, and these factors' influences were largely independent. Because children of teenage mothers with a modest set of resources were not predicted to have compromised development, resources provided in early childhood may have the potential to reduce developmental disparities for teenage mothers' children.

  4. Thrive or Survive? Explaining Variation in Economic Outcomes for Refugees

    Directory of Open Access Journals (Sweden)

    Alexander Betts

    2017-11-01

    Full Text Available In the context of protracted refugee situations, there has been a revival in concern among policymakers to transcend the so-called humanitarian-development divide and create greater opportunities for self-reliance. Yet, these discussions too often neglect an analytical focus on refugees’ own economic lives, and their own interactions with markets.Despite a growing literature on the economic lives of refugees, much of that work has lacked theory or data. The work that has been quantitative has generally focused on the economic impact of refugees on host countries rather than explaining variation in economic outcomes for refugees.  In order to explain variation in economic outcomes for refugees, this paper asks three questions about the economic lives of refugees: 1 what makes the economic lives of refugees distinctive from other populations; 2 what explains variation in refugees’ income levels; and 3 what role does entrepreneurship play in shaping refugees’ economic outcomes?In order to answer these questions, the paper draws upon extensive qualitative and quantitative research conducted in Uganda by the Humanitarian Innovation Project at Oxford University. The quantitative data set is based on a survey of 2,213 refugees in three types of contexts: urban (Kampala, protracted camps (Nakivale and Kyangwali settlements, and emergency camps (Rwamwanja. It supplements this with qualitative research from other parts of Africa and the Middle East. The economic lives of refugees are argued to be distinctive not because refugees are any different qua human beings but because they often occupy a distinctive institutional space. Following new institutional economics, the paper argues that “refugee economies” represent a distinctive analytical space insofar as refugees face different formal and informal institutional barriers and distortions in their economic lives compared to nationals or other migrants. Even within the same country, refugees

  5. Explaining rigid dieting in normal-weight women: the key role of body image inflexibility.

    Science.gov (United States)

    Ferreira, Cláudia; Trindade, Inês A; Martinho, Ana

    2016-03-01

    Restrictive dieting is an increasing behavior presented by women in modern societies, independently of their weight. There are several known factors that motivate diet, namely a sense of dissatisfaction with one's body and unfavorable social comparisons based on physical appearance. However, dieting seems to have a paradoxical effect and has been considered a risk factor for weight gain and obesity in women and for maladaptive eating. Nevertheless, the study of the emotional regulation processes that explain the adoption of inflexible and rigid eating behaviors still remains little explored. In this line, the present study aims to explore why normal-weight women engage in highly rigid and inflexible diets. We hypothesize that body and weight dissatisfaction and unfavorable social comparisons based on physical appearance explain the adoption of inflexible eating rules, through the mechanisms of body image inflexibility. The current study comprised 508 normal-weight female college students. Path analyses were conducted to explore the study's hypotheses. Results revealed that the model explained 43 % of inflexible eating and revealed excellent fit indices. Furthermore, the unwillingness to experience unwanted events related to body image (body image inflexibility) mediated the impact of body dissatisfaction and unfavorable social comparisons on the adoption of inflexible eating rules. This study highlights the relevance of body image inflexibility to explain rigid eating attitudes, and it seems to be an important avenue for the development of interventions focusing on the promotion of adaptive attitudes towards body image and eating in young women.

  6. Semantic language as a mechanism explaining the association between ADHD symptoms and reading and mathematics underachievement.

    Science.gov (United States)

    Gremillion, Monica L; Martel, Michelle M

    2012-11-01

    ADHD is associated with academic underachievement, but it remains unclear what mechanism accounts for this association. Semantic language is an underexplored mechanism that provides a developmental explanation for this association. The present study will examine whether semantic language deficits explain the association between ADHD and reading and mathematics underachievement, taking into account alternative explanations for associations, including verbal working memory (WM) impairments, as well as specificity of effects to inattentive and hyperactive-impulsive ADHD symptom domains. Participants in this cross-sectional study were 546 children (54 % male) ages six to twelve (M = 9.77, SD = 1.49). ADHD symptoms were measured via maternal and teacher report during structured interviews and on standardized rating forms. Children completed standardized semantic language, verbal WM, and academic testing. Semantic language fully mediated the ADHD-reading achievement association and partially mediated the ADHD-mathematics achievement association. Verbal WM also partially mediated the ADHD-mathematics association but did not mediate the ADHD-reading achievement association. Results generalized across inattentive and hyperactive-impulsive ADHD symptom domains. Semantic language explained the association between ADHD and reading underachievement and partially explained the association between ADHD and mathematics underachievement. Together, language impairment and WM fully explained the association between ADHD and reading underachievement, in line with developmental models suggesting that language and WM conjointly influence the development of attention and subsequent academic achievement. This work has implication for the development of tailored interventions for academic underachievement in children with ADHD.

  7. Changes in variance explained by top SNP windows over generations for three traits in broiler chicken.

    Science.gov (United States)

    Fragomeni, Breno de Oliveira; Misztal, Ignacy; Lourenco, Daniela Lino; Aguilar, Ignacio; Okimoto, Ronald; Muir, William M

    2014-01-01

    The purpose of this study was to determine if the set of genomic regions inferred as accounting for the majority of genetic variation in quantitative traits remain stable over multiple generations of selection. The data set contained phenotypes for five generations of broiler chicken for body weight, breast meat, and leg score. The population consisted of 294,632 animals over five generations and also included genotypes of 41,036 single nucleotide polymorphism (SNP) for 4,866 animals, after quality control. The SNP effects were calculated by a GWAS type analysis using single step genomic BLUP approach for generations 1-3, 2-4, 3-5, and 1-5. Variances were calculated for windows of 20 SNP. The top ten windows for each trait that explained the largest fraction of the genetic variance across generations were examined. Across generations, the top 10 windows explained more than 0.5% but less than 1% of the total variance. Also, the pattern of the windows was not consistent across generations. The windows that explained the greatest variance changed greatly among the combinations of generations, with a few exceptions. In many cases, a window identified as top for one combination, explained less than 0.1% for the other combinations. We conclude that identification of top SNP windows for a population may have little predictive power for genetic selection in the following generations for the traits here evaluated.

  8. From laggard to leader: Explaining offshore wind developments in the UK

    International Nuclear Information System (INIS)

    Kern, Florian; Smith, Adrian; Shaw, Chris; Raven, Rob; Verhees, Bram

    2014-01-01

    Offshore wind technology has recently undergone rapid deployment in the UK. And yet, up until recently, the UK was considered a laggard in terms of deploying renewable energy. How can this burst of offshore wind activity be explained? An economic analysis would seek signs for newfound competitiveness for offshore wind in energy markets. A policy analysis would highlight renewable energy policy developments and assess their contribution to economic prospects of offshore wind. However, neither perspective sheds sufficient light on the advocacy of the actors involved in the development and deployment of the technology. Without an account of technology politics it is hard to explain continuing policy support despite rising costs. By analysing the actor networks and narratives underpinning policy support for offshore wind, we explain how a fairly effective protective space was constructed through the enroling of key political and economic interests. - Highlights: • UK is world leader in offshore wind deployment. • Article explains boom in deployment by looking at the politics of renewable energy policy. • Offshore wind is supported by a variety of actors with aligned political and economic interests. • Analysis highlights the importance of a system builder

  9. The boundaries of instance-based learning theory for explaining decisions from experience.

    Science.gov (United States)

    Gonzalez, Cleotilde

    2013-01-01

    Most demonstrations of how people make decisions in risky situations rely on decisions from description, where outcomes and their probabilities are explicitly stated. But recently, more attention has been given to decisions from experience where people discover these outcomes and probabilities through exploration. More importantly, risky behavior depends on how decisions are made (from description or experience), and although prospect theory explains decisions from description, a comprehensive model of decisions from experience is yet to be found. Instance-based learning theory (IBLT) explains how decisions are made from experience through interactions with dynamic environments (Gonzalez et al., 2003). The theory has shown robust explanations of behavior across multiple tasks and contexts, but it is becoming unclear what the theory is able to explain and what it does not. The goal of this chapter is to start addressing this problem. I will introduce IBLT and a recent cognitive model based on this theory: the IBL model of repeated binary choice; then I will discuss the phenomena that the IBL model explains and those that the model does not. The argument is for the theory's robustness but also for clarity in terms of concrete effects that the theory can or cannot account for. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Thermally-assisted Magma Emplacement Explains Restless Calderas

    Science.gov (United States)

    Amoruso, A.; Crescentini, L.; D'Antonio, M.; Acocella, V.

    2017-12-01

    Many calderas show repeated unrest over centuries. Though probably induced by magma, this unique behaviour is not understood and its dynamics remains elusive. To better understand these restless calderas, we interpret deformation data and build thermal models of Campi Flegrei, Italy, which is the best-known, yet most dangerous calderas, lying to the west of Naples and restless since the 1950s at least.Our elaboration of the geodetic data indicates that the inflation and deflation of magmatic sources at the same location explain most deformation, at least since the build-up of the last 1538 AD eruption. However, such a repeated magma emplacement requires a persistently hot crust.Our thermal models show that the repeated emplacement was assisted by the thermal anomaly created by magma that was intruded at shallow depth 3 ka before the last eruption and, in turn, contributed to maintain the thermal anomaly itself. This may explain the persistence of the magmatic sources promoting the restless behaviour of the Campi Flegrei caldera; moreover, it explains the crystallization, re-melting and mixing among compositionally distinct magmas recorded in young volcanic rocks.Available information at other calderas highlights similarities to Campi Flegrei, in the pattern and cause of unrest. All monitored restless calderas have either geodetically (Yellowstone, Aira Iwo-Jima, Askja, Fernandina and, partly, Long Valley) or geophysically (Rabaul, Okmok) detected sill-like intrusions inducing repeated unrest. Some calderas (Yellowstone, Long Valley) also show stable deformation pattern, where inflation insists on and mimics the resurgence uplift. The common existence of sill-like sources, also responsible for stable deformation patterns, in restless calderas suggests close similarities to Campi Flegrei. This suggests a wider applicability of our model of thermally-assisted sill emplacement, to be tested by future studies to better understand not only the dynamics of restless

  11. Explaining socioeconomic inequalities in exclusive breast feeding in Norway.

    Science.gov (United States)

    Bærug, Anne; Laake, Petter; Løland, Beate Fossum; Tylleskär, Thorkild; Tufte, Elisabeth; Fretheim, Atle

    2017-08-01

    In high-income countries, lower socioeconomic position is associated with lower rates of breast feeding, but it is unclear what factors explain this inequality. Our objective was to examine the association between socioeconomic position and exclusive breast feeding, and to explore whether socioeconomic inequality in exclusive breast feeding could be explained by other sociodemographic characteristics, for example, maternal age and parity, smoking habits, birth characteristics, quality of counselling and breastfeeding difficulties. We used data from a questionnaire sent to mothers when their infants were five completed months as part of a trial of a breastfeeding intervention in Norway. We used maternal education as an indicator of socioeconomic position. Analyses of 1598 mother-infant pairs were conducted using logistic regression to assess explanatory factors of educational inequalities in breast feeding. Socioeconomic inequalities in exclusive breast feeding were present from the beginning and persisted for five completed months, when 22% of the most educated mothers exclusively breast fed compared with 7% of the least educated mothers: OR 3.39 (95% CI 1.74 to 6.61). After adjustment for all potentially explanatory factors, the OR was reduced to 1.49 (95% CI 0.70 to 3.14). This decrease in educational inequality seemed to be mainly driven by sociodemographic factors, smoking habits and breastfeeding difficulties, in particular perceived milk insufficiency. Socioeconomic inequalities in exclusive breast feeding at 5 months were largely explained by sociodemographic factors, but also by modifiable factors, such as smoking habits and breastfeeding difficulties, which can be amenable to public health interventions. NCT01025362. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  12. Blazar spectral variability as explained by a twisted inhomogeneous jet.

    Science.gov (United States)

    Raiteri, C M; Villata, M; Acosta-Pulido, J A; Agudo, I; Arkharov, A A; Bachev, R; Baida, G V; Benítez, E; Borman, G A; Boschin, W; Bozhilov, V; Butuzova, M S; Calcidese, P; Carnerero, M I; Carosati, D; Casadio, C; Castro-Segura, N; Chen, W-P; Damljanovic, G; D'Ammando, F; Di Paola, A; Echevarría, J; Efimova, N V; Ehgamberdiev, Sh A; Espinosa, C; Fuentes, A; Giunta, A; Gómez, J L; Grishina, T S; Gurwell, M A; Hiriart, D; Jermak, H; Jordan, B; Jorstad, S G; Joshi, M; Kopatskaya, E N; Kuratov, K; Kurtanidze, O M; Kurtanidze, S O; Lähteenmäki, A; Larionov, V M; Larionova, E G; Larionova, L V; Lázaro, C; Lin, C S; Malmrose, M P; Marscher, A P; Matsumoto, K; McBreen, B; Michel, R; Mihov, B; Minev, M; Mirzaqulov, D O; Mokrushina, A A; Molina, S N; Moody, J W; Morozova, D A; Nazarov, S V; Nikolashvili, M G; Ohlert, J M; Okhmat, D N; Ovcharov, E; Pinna, F; Polakis, T A; Protasio, C; Pursimo, T; Redondo-Lorenzo, F J; Rizzi, N; Rodriguez-Coira, G; Sadakane, K; Sadun, A C; Samal, M R; Savchenko, S S; Semkov, E; Skiff, B A; Slavcheva-Mihova, L; Smith, P S; Steele, I A; Strigachev, A; Tammi, J; Thum, C; Tornikoski, M; Troitskaya, Yu V; Troitsky, I S; Vasilyev, A A; Vince, O

    2017-12-21

    Blazars are active galactic nuclei, which are powerful sources of radiation whose central engine is located in the core of the host galaxy. Blazar emission is dominated by non-thermal radiation from a jet that moves relativistically towards us, and therefore undergoes Doppler beaming. This beaming causes flux enhancement and contraction of the variability timescales, so that most blazars appear as luminous sources characterized by noticeable and fast changes in brightness at all frequencies. The mechanism that produces this unpredictable variability is under debate, but proposed mechanisms include injection, acceleration and cooling of particles, with possible intervention of shock waves or turbulence. Changes in the viewing angle of the observed emitting knots or jet regions have also been suggested as an explanation of flaring events and can also explain specific properties of blazar emission, such as intra-day variability, quasi-periodicity and the delay of radio flux variations relative to optical changes. Such a geometric interpretation, however, is not universally accepted because alternative explanations based on changes in physical conditions-such as the size and speed of the emitting zone, the magnetic field, the number of emitting particles and their energy distribution-can explain snapshots of the spectral behaviour of blazars in many cases. Here we report the results of optical-to-radio-wavelength monitoring of the blazar CTA 102 and show that the observed long-term trends of the flux and spectral variability are best explained by an inhomogeneous, curved jet that undergoes changes in orientation over time. We propose that magnetohydrodynamic instabilities or rotation of the twisted jet cause different jet regions to change their orientation and hence their relative Doppler factors. In particular, the extreme optical outburst of 2016-2017 (brightness increase of six magnitudes) occurred when the corresponding emitting region had a small viewing angle

  13. Blazar spectral variability as explained by a twisted inhomogeneous jet

    Science.gov (United States)

    Raiteri, C. M.; Villata, M.; Acosta-Pulido, J. A.; Agudo, I.; Arkharov, A. A.; Bachev, R.; Baida, G. V.; Benítez, E.; Borman, G. A.; Boschin, W.; Bozhilov, V.; Butuzova, M. S.; Calcidese, P.; Carnerero, M. I.; Carosati, D.; Casadio, C.; Castro-Segura, N.; Chen, W.-P.; Damljanovic, G.; D'Ammando, F.; di Paola, A.; Echevarría, J.; Efimova, N. V.; Ehgamberdiev, Sh. A.; Espinosa, C.; Fuentes, A.; Giunta, A.; Gómez, J. L.; Grishina, T. S.; Gurwell, M. A.; Hiriart, D.; Jermak, H.; Jordan, B.; Jorstad, S. G.; Joshi, M.; Kopatskaya, E. N.; Kuratov, K.; Kurtanidze, O. M.; Kurtanidze, S. O.; Lähteenmäki, A.; Larionov, V. M.; Larionova, E. G.; Larionova, L. V.; Lázaro, C.; Lin, C. S.; Malmrose, M. P.; Marscher, A. P.; Matsumoto, K.; McBreen, B.; Michel, R.; Mihov, B.; Minev, M.; Mirzaqulov, D. O.; Mokrushina, A. A.; Molina, S. N.; Moody, J. W.; Morozova, D. A.; Nazarov, S. V.; Nikolashvili, M. G.; Ohlert, J. M.; Okhmat, D. N.; Ovcharov, E.; Pinna, F.; Polakis, T. A.; Protasio, C.; Pursimo, T.; Redondo-Lorenzo, F. J.; Rizzi, N.; Rodriguez-Coira, G.; Sadakane, K.; Sadun, A. C.; Samal, M. R.; Savchenko, S. S.; Semkov, E.; Skiff, B. A.; Slavcheva-Mihova, L.; Smith, P. S.; Steele, I. A.; Strigachev, A.; Tammi, J.; Thum, C.; Tornikoski, M.; Troitskaya, Yu. V.; Troitsky, I. S.; Vasilyev, A. A.; Vince, O.

    2017-12-01

    Blazars are active galactic nuclei, which are powerful sources of radiation whose central engine is located in the core of the host galaxy. Blazar emission is dominated by non-thermal radiation from a jet that moves relativistically towards us, and therefore undergoes Doppler beaming. This beaming causes flux enhancement and contraction of the variability timescales, so that most blazars appear as luminous sources characterized by noticeable and fast changes in brightness at all frequencies. The mechanism that produces this unpredictable variability is under debate, but proposed mechanisms include injection, acceleration and cooling of particles, with possible intervention of shock waves or turbulence. Changes in the viewing angle of the observed emitting knots or jet regions have also been suggested as an explanation of flaring events and can also explain specific properties of blazar emission, such as intra-day variability, quasi-periodicity and the delay of radio flux variations relative to optical changes. Such a geometric interpretation, however, is not universally accepted because alternative explanations based on changes in physical conditions—such as the size and speed of the emitting zone, the magnetic field, the number of emitting particles and their energy distribution—can explain snapshots of the spectral behaviour of blazars in many cases. Here we report the results of optical-to-radio-wavelength monitoring of the blazar CTA 102 and show that the observed long-term trends of the flux and spectral variability are best explained by an inhomogeneous, curved jet that undergoes changes in orientation over time. We propose that magnetohydrodynamic instabilities or rotation of the twisted jet cause different jet regions to change their orientation and hence their relative Doppler factors. In particular, the extreme optical outburst of 2016–2017 (brightness increase of six magnitudes) occurred when the corresponding emitting region had a small viewing

  14. Explaining Home Bias in Trade: The Role of Time Costs

    Directory of Open Access Journals (Sweden)

    Inkoo Lee

    2010-12-01

    Full Text Available We study how time costs, combined with elasticity of substitution across home and foreign goods, can explain the home bias puzzle in a framework of flexible prices. Using a simple two-country model, we show that introducing time costs to an otherwise standard competitive model improves its ability to rationalize home bias in trade. Our analysis suggests that home bias and corresponding incomplete risk-sharing naturally arise in the presence of time costs, even under the assumption of complete financial markets and low elasticity of substitution between home and foreign goods.

  15. Explaining consumer attitudes to genetic modification in food production

    DEFF Research Database (Denmark)

    Bredahl, Lone

    Consumers have not had many possibilities yet for seeking out, buying and consuming genetically modified food products. However, for various reasons consumer attitude formation with regard to these products is likely to be complex and closely related to personal values. The paper presents a model...... for explaining consumer attitudes to genetic modification in food production which builds on modern cognitive psychology and multi-attribute attitude theory. In addition, the paper introduces the empirical research which is undertaken at present to validate and estimate the parameters of the model by means...

  16. Explaining human uniqueness: genome interactions with environment, behaviour and culture

    Science.gov (United States)

    Varki, Ajit; Geschwind, Daniel H.; Eichler, Evan E.

    2009-01-01

    What makes us human? Specialists in each discipline respond through the lens of their own expertise. In fact, ‘anthropogeny’ (explaining the origin of humans) requires a transdisciplinary approach that eschews such barriers. Here we take a genomic and genetic perspective towards molecular variation, explore systems analysis of gene expression and discuss an organ-systems approach. Rejecting any ‘genes versus environment’ dichotomy, we then consider genome interactions with environment, behaviour and culture, finally speculating that aspects of human uniqueness arose because of a primate evolutionary trend towards increasing and irreversible dependence on learned behaviours and culture — perhaps relaxing allowable thresholds for large-scale genomic diversity. PMID:18802414

  17. Socially-embedded investments: Explaining gender differences in job-specific skills

    OpenAIRE

    Javier G. Polavieja

    2010-01-01

    Gender-differences in post-schooling skill investments play a central role in stratification processes. Yet little research has been devoted to explaining how these differences come about. This paperhelps to fill this gap by proposing and testing a job-investment model with social-interaction effects that melds substantive ideas of sociology and economics. Firms use strategic compensation profiles in order to protect their job-specific skill investments and this shifts the weight of the inves...

  18. Reinforcement Learning Explains Conditional Cooperation and Its Moody Cousin.

    Directory of Open Access Journals (Sweden)

    Takahiro Ezaki

    2016-07-01

    Full Text Available Direct reciprocity, or repeated interaction, is a main mechanism to sustain cooperation under social dilemmas involving two individuals. For larger groups and networks, which are probably more relevant to understanding and engineering our society, experiments employing repeated multiplayer social dilemma games have suggested that humans often show conditional cooperation behavior and its moody variant. Mechanisms underlying these behaviors largely remain unclear. Here we provide a proximate account for this behavior by showing that individuals adopting a type of reinforcement learning, called aspiration learning, phenomenologically behave as conditional cooperator. By definition, individuals are satisfied if and only if the obtained payoff is larger than a fixed aspiration level. They reinforce actions that have resulted in satisfactory outcomes and anti-reinforce those yielding unsatisfactory outcomes. The results obtained in the present study are general in that they explain extant experimental results obtained for both so-called moody and non-moody conditional cooperation, prisoner's dilemma and public goods games, and well-mixed groups and networks. Different from the previous theory, individuals are assumed to have no access to information about what other individuals are doing such that they cannot explicitly use conditional cooperation rules. In this sense, myopic aspiration learning in which the unconditional propensity of cooperation is modulated in every discrete time step explains conditional behavior of humans. Aspiration learners showing (moody conditional cooperation obeyed a noisy GRIM-like strategy. This is different from the Pavlov, a reinforcement learning strategy promoting mutual cooperation in two-player situations.

  19. Mycorrhizal status helps explain invasion success of alien plant species.

    Science.gov (United States)

    Menzel, Andreas; Hempel, Stefan; Klotz, Stefan; Moora, Mari; Pyšek, Petr; Rillig, Matthias C; Zobel, Martin; Kühn, Ingolf

    2017-01-01

    It is still debated whether alien plants benefit from being mycorrhizal, or if engaging in the symbiosis constrains their establishment and spread in new regions. We analyzed the association between mycorrhizal status of alien plant species in Germany and their invasion success. We compared whether the representation of species with different mycorrhizal status (obligate, facultative, or non-mycorrhizal) differed at several stages of the invasion process. We used generalized linear models to explain the occupied geographical range of alien plants, incorporating interactions of mycorrhizal status with plant traits related to morphology, reproduction, and life-history. Non-naturalized aliens did not differ from naturalized aliens in the relative frequency of different mycorrhizal status categories. Mycorrhizal status significantly explained the occupied range of alien plants; with facultative mycorrhizal species inhabiting a larger range than non-mycorrhizal aliens and obligate mycorrhizal plant species taking an intermediate position. Aliens with storage organs, shoot metamorphoses, or specialized structures promoting vegetative dispersal occupied a larger range when being facultative mycorrhizal. We conclude that being mycorrhizal is important for the persistence of aliens in Germany and constitutes an advantage compared to being non-mycorrhizal. Being facultative mycorrhizal seems to be especially advantageous for successful spread, as the flexibility of this mycorrhizal status may enable plants to use a broader set of ecological strategies. © 2016 by the Ecological Society of America.

  20. Localized bedrock aquifer distribution explains discharge from a headwater catchment

    Science.gov (United States)

    Kosugi, Ken'ichirou; Fujimoto, Masamitsu; Katsura, Shin'ya; Kato, Hiroyuki; Sando, Yoshiki; Mizuyama, Takahisa

    2011-07-01

    Understanding a discharge hydrograph is one of the leading interests in catchment hydrology. Recent research has provided credible information on the importance of bedrock groundwater on discharge hydrographs from headwater catchments. However, intensive monitoring of bedrock groundwater is rare in mountains with steep topography. Hence, how bedrock groundwater controls discharge from a steep headwater catchment is in dispute. In this study, we conducted long-term hydrological observations using densely located bedrock wells in a headwater catchment underlain by granitic bedrock. The catchment has steep topography affected by diastrophic activities. Results showed a fairly regionalized distribution of bedrock aquifers within a scale of tens of meters, consisting of upper, middle, and lower aquifers, instead of a gradual and continuous decline in water level from ridge to valley bottom. This was presumably attributable to the unique bedrock structure; fault lines developed in the watershed worked to form divides between the bedrock aquifers. Spatial expanse of each aquifer and the interaction among aquifers were key factors to explain gentle and considerable variations in the base flow discharge and triple-peak discharge responses of the observed hydrograph. A simple model was developed to simulate the discharge hydrograph, which computed each of the contributions from the soil mantle groundwater, from the lower aquifer, and from the middle aquifer to the discharge. The modeling results generally succeeded in reproducing the observed hydrograph. Thus, this study demonstrated that understanding regionalized bedrock aquifer distribution is pivotal for explaining discharge hydrograph from headwater catchments that have been affected by diastrophic activities.

  1. Do sex differences in rumination explain sex differences in depression?

    Science.gov (United States)

    Shors, Tracey J; Millon, Emma M; Chang, Han Yan M; Olson, Ryan L; Alderman, Brandon L

    2017-01-02

    It is generally accepted that women tend to ruminate more than men do and these thought patterns are often associated with depressive symptoms (Nolen-Hoeksema et al., ). Based on these findings, we considered whether the relationship between rumination and depression is stronger in women than in men and if so, whether this might explain the higher prevalence of major depressive disorder (MDD) in women and finally, whether the association can be disrupted through a mind/body intervention. Adult men and women, most of whom were clinically depressed, participated in an intervention known as MAP Training, which combines "mental" training with silent meditation and "physical" training with aerobic exercise (Shors et al., ). After eight weeks of training, both men and women reported significantly fewer symptoms of depression and fewer ruminative thoughts (Alderman et al., ). Statistical correlations between depressive symptoms and ruminative thoughts were strong and significant (rho > 0.50; p MAP Training. However, only in women did depressive symptoms relate to "reflective" ruminations, which involve analyses of past events, feelings, and behaviors. This is also the only relationship that dissipated after the intervention. In general, these analyses suggest that the strength of the relationship between depressive symptoms and rumination does not necessarily explain sex differences in depression; but because the relationship is strong, targeting rumination through intervention can reduce the incidence of MDD, which is more prevalent among women. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  2. Leveraging population admixture to explain missing heritability of complex traits

    Science.gov (United States)

    Zaitlen, Noah; Pasaniuc, Bogdan; Sankararaman, Sriram; Bhatia, Gaurav; Zhang, Jianqi; Gusev, Alexander; Young, Taylor; Tandon, Arti; Pollack, Samuela; Vilhjálmsson, Bjarni J.; Assimes, Themistocles L.; Berndt, Sonja I.; Blot, William J.; Chanock, Stephen; Franceschini, Nora; Goodman, Phyllis G.; He, Jing; Hennis, Anselm JM; Hsing, Ann; Ingles, Sue A.; Isaacs, William; Kittles, Rick A.; Klein, Eric A.; Lange, Leslie A.; Nemesure, Barbara; Patterson, Nick; Reich, David; Rybicki, Benjamin A.; Stanford, Janet L.; Stevens, Victoria L; Strom, Sara S.; Whitsel, Eric A; Witte, John S.; Xu, Jianfeng; Haiman, Christopher; Wilson, James G.; Kooperberg, Charles; Stram, Daniel; Reiner, Alex P.; Tang, Hua; Price, Alkes L.

    2014-01-01

    Despite recent progress on estimating the heritability explained by genotyped SNPs (hg2), a large gap between hg2 and estimates of total narrow-sense heritability (h2) remains. Explanations for this gap include rare variants, or upward bias in family-based estimates of h2 due to shared environment or epistasis. We estimate h2 from unrelated individuals in admixed populations by first estimating the heritability explained by local ancestry (hγ2). We show that hγ2 = 2FSTCθ(1−θ)h2, where FSTC measures frequency differences between populations at causal loci and θ is the genome-wide ancestry proportion. Our approach is not susceptible to biases caused by epistasis or shared environment. We examined 21,497 African Americans from three cohorts, analyzing 13 phenotypes. For height and BMI, we obtained h2 estimates of 0.55 ± 0.09 and 0.23 ± 0.06, respectively, which are larger than estimates of hg2 in these and other data, but smaller than family-based estimates of h2. PMID:25383972

  3. Mackay icosahedron explaining orientation relationship of dispersoids in aluminium alloys.

    Science.gov (United States)

    Muggerud, Astrid Marie F; Li, Yanjun; Holmestad, Randi; Andersen, Sigmund J

    2014-10-01

    The orientation relations (ORs) of the cubic icosahedral quasicrystal approximant phase α-Al(Fe,Mn)Si have been studied after low temperature annealing of a 3xxx wrought aluminium alloy by transmission electron microscopy. From diffraction studies it was verified that the most commonly observed OR for the α-Al(Fe,Mn)Si dispersoids is [1\\bar 11]α // [1\\bar 11]Al, (5\\bar 2\\bar 7)α // (011)Al. This orientation could be explained by assuming that the internal Mackay icosahedron (MI) in the α-phase has a fixed orientation in relation to Al, similar to that of the icosahedral quasi-crystals existing in this alloy system. It is shown that mirroring of the normal-to-high-symmetry icosahedral directions of the MI explains the alternative orientations, which are therefore likely to be caused by twinning of the fixed MI. Only one exception was found, which was related to the Bergman icosahedron internal to the T-phase of the Al-Mg-Zn system.

  4. Reinforcement Learning Explains Conditional Cooperation and Its Moody Cousin.

    Science.gov (United States)

    Ezaki, Takahiro; Horita, Yutaka; Takezawa, Masanori; Masuda, Naoki

    2016-07-01

    Direct reciprocity, or repeated interaction, is a main mechanism to sustain cooperation under social dilemmas involving two individuals. For larger groups and networks, which are probably more relevant to understanding and engineering our society, experiments employing repeated multiplayer social dilemma games have suggested that humans often show conditional cooperation behavior and its moody variant. Mechanisms underlying these behaviors largely remain unclear. Here we provide a proximate account for this behavior by showing that individuals adopting a type of reinforcement learning, called aspiration learning, phenomenologically behave as conditional cooperator. By definition, individuals are satisfied if and only if the obtained payoff is larger than a fixed aspiration level. They reinforce actions that have resulted in satisfactory outcomes and anti-reinforce those yielding unsatisfactory outcomes. The results obtained in the present study are general in that they explain extant experimental results obtained for both so-called moody and non-moody conditional cooperation, prisoner's dilemma and public goods games, and well-mixed groups and networks. Different from the previous theory, individuals are assumed to have no access to information about what other individuals are doing such that they cannot explicitly use conditional cooperation rules. In this sense, myopic aspiration learning in which the unconditional propensity of cooperation is modulated in every discrete time step explains conditional behavior of humans. Aspiration learners showing (moody) conditional cooperation obeyed a noisy GRIM-like strategy. This is different from the Pavlov, a reinforcement learning strategy promoting mutual cooperation in two-player situations.

  5. MEMINIMALKAN MISKONSEPSI PADA MATERI RANGKAIAN LISTRIK DENGAN PEMBELAJARAN PREDICT-OBSERVE-EXPLAIN

    Directory of Open Access Journals (Sweden)

    Mursalin

    2014-09-01

    Full Text Available Abstract: Minimizing Misconceptions on the Topic of Electric Circuits by Predict-Observe-Explain Learning. This pretest-posttest control group experiment was aimed to improve students’ understanding of the concept and to minimize their misconceptions on the topic of electric circuits. The subjects were se­lected using cluster random sampling from high school students in Gorontalo. The instruments used to collect the data included pretest, posttest and questionnaires. The data were analyzed using t-test. The students' conception profiles were carried out using Certainty of Response Index (CRI technique. The results show the significant difference in the posttest average and normalized gain average between the experimental and the control classes. The results are supported by the fact that misconceptions in the experimental class are smaller than those in the control class. The application of predict-observe-explain learning is effective to improve the understanding of the concept and minimize the misconceptions. Keywords: Predict-Observe-Explain Learning, concept understandings, misconception, electric circuits Abstrak: Meminimalkan Miskonsepsi pada Materi Rangkaian Listrik dengan Pembelajaran Predict-Observe-Predict. Artikel hasil penelitian ini memaparkan mengenai upaya meningkatkan pemahaman konsep dan meminimalkan miskonsepsi pada materi rangkaian listrik dengan menggunakan model pem­belajaran Predict-Observe-Explain (POE. Penelitian dilakukan secara eksperimen dengan pretest-posttest control group design. Subyek penelitian ditentukan dengan teknik cluster random sampling dari siswa SMA kelas X suatu sekolah di Kota Gorontalo. Analisis data dilakukan dengan uji beda rerata gain ternormalisasi antara kelas eksperimen dan kelas kontrol, dan profil konsepsi siswa dianalisis dengan teknik Certainty of Response Index. Hasil penelitian mengungkap bahwa penerapan model pembelajaran POE efektif mening­katkan pemahaman konsep dan meminimalkan

  6. Characteristics of broadband slow earthquakes explained by a Brownian model

    Science.gov (United States)

    Ide, S.; Takeo, A.

    2017-12-01

    Brownian slow earthquake (BSE) model (Ide, 2008; 2010) is a stochastic model for the temporal change of seismic moment release by slow earthquakes, which can be considered as a broadband phenomena including tectonic tremors, low frequency earthquakes, and very low frequency (VLF) earthquakes in the seismological frequency range, and slow slip events in geodetic range. Although the concept of broadband slow earthquake may not have been widely accepted, most of recent observations are consistent with this concept. Then, we review the characteristics of slow earthquakes and how they are explained by BSE model. In BSE model, the characteristic size of slow earthquake source is represented by a random variable, changed by a Gaussian fluctuation added at every time step. The model also includes a time constant, which divides the model behavior into short- and long-time regimes. In nature, the time constant corresponds to the spatial limit of tremor/SSE zone. In the long-time regime, the seismic moment rate is constant, which explains the moment-duration scaling law (Ide et al., 2007). For a shorter duration, the moment rate increases with size, as often observed for VLF earthquakes (Ide et al., 2008). The ratio between seismic energy and seismic moment is constant, as shown in Japan, Cascadia, and Mexico (Maury et al., 2017). The moment rate spectrum has a section of -1 slope, limited by two frequencies corresponding to the above time constant and the time increment of the stochastic process. Such broadband spectra have been observed for slow earthquakes near the trench axis (Kaneko et al., 2017). This spectrum also explains why we can obtain VLF signals by stacking broadband seismograms relative to tremor occurrence (e.g., Takeo et al., 2010; Ide and Yabe, 2014). The fluctuation in BSE model can be non-Gaussian, as far as the variance is finite, as supported by the central limit theorem. Recent observations suggest that tremors and LFEs are spatially characteristic

  7. Explaining superfoods: exploring metaphor scenarios in media science reports

    Directory of Open Access Journals (Sweden)

    Ruth Breeze

    2017-10-01

    Full Text Available Metaphorical language plays an important role in spreading and popularising scientific information. However, little is known about the process through which sober scientific research is transformed into colourful or even sensational news. This paper examines the main metaphor scenarios used to explain nutritional discoveries, generally related to the overarching metaphors of “combat” and “maintenance”, and explores how they are developed and distributed across institutional press releases, online news reports, and magazines/blogs. Most of the metaphor scenarios seem to arise first in the press release, but these are considerably extended and embellished by the other media. Only occasionally are new metaphor scenarios engaged, which reflect societal discourses concerning science and nutrition.

  8. [Nurses are not into personal marketing: do history explain why?].

    Science.gov (United States)

    Gentil, Rosana Chami

    2009-01-01

    Reflection on the nurse's personal marketing based on beliefs and values explained by the history of the main characters that care for patients. It brings to the surface reflections on the ambiguity between the social image of nursing and scientific, technological and humanistic knowledge developed over the time. It recognizes that there is still a fixation on the attributes relating to attitude and moral of the professionals to the detriment of having high regard for the technical and scientific knowledge. It verifies that the History of Nursing allows understanding that the fight against prejudice in the collective imagination lends weight to the social acceptance and recognition of this profession through the promotion of Nursing Science and the demonstration of its application in the professional practice.

  9. Social inheritance can explain the structure of animal social networks

    Science.gov (United States)

    Ilany, Amiyaal; Akçay, Erol

    2016-01-01

    The social network structure of animal populations has major implications for survival, reproductive success, sexual selection and pathogen transmission of individuals. But as of yet, no general theory of social network structure exists that can explain the diversity of social networks observed in nature, and serve as a null model for detecting species and population-specific factors. Here we propose a simple and generally applicable model of social network structure. We consider the emergence of network structure as a result of social inheritance, in which newborns are likely to bond with maternal contacts, and via forming bonds randomly. We compare model output with data from several species, showing that it can generate networks with properties such as those observed in real social systems. Our model demonstrates that important observed properties of social networks, including heritability of network position or assortative associations, can be understood as consequences of social inheritance. PMID:27352101

  10. Muon-Induced Neutrons Do Not Explain the DAMA Data

    Science.gov (United States)

    Klinger, J.; Kudryavtsev, V. A.

    2015-04-01

    We present an accurate model of the muon-induced background in the DAMA/LIBRA experiment. Our work challenges proposed mechanisms which seek to explain the observed DAMA signal modulation with muon-induced backgrounds. Muon generation and transport are performed using the MUSIC /MUSUN code, and subsequent interactions in the vicinity of the DAMA detector cavern are simulated with Geant4. We estimate the total muon-induced neutron flux in the detector cavern to be Φnν=1.0 ×10-9 cm-2 s-1 . We predict 3.49 ×10-5 counts /day /kg /keV , which accounts for less than 0.3% of the DAMA signal modulation amplitude.

  11. Modern elementary particle physics explaining and extending the standard model

    CERN Document Server

    Kane, Gordon

    2017-01-01

    This book is written for students and scientists wanting to learn about the Standard Model of particle physics. Only an introductory course knowledge about quantum theory is needed. The text provides a pedagogical description of the theory, and incorporates the recent Higgs boson and top quark discoveries. With its clear and engaging style, this new edition retains its essential simplicity. Long and detailed calculations are replaced by simple approximate ones. It includes introductions to accelerators, colliders, and detectors, and several main experimental tests of the Standard Model are explained. Descriptions of some well-motivated extensions of the Standard Model prepare the reader for new developments. It emphasizes the concepts of gauge theories and Higgs physics, electroweak unification and symmetry breaking, and how force strengths vary with energy, providing a solid foundation for those working in the field, and for those who simply want to learn about the Standard Model.

  12. Explaining social discrimination: racism in Brazil and xenophobia in Spain.

    Science.gov (United States)

    Camino, Leoncio; Álvaro, José Luis; Torres, Ana Raquel R; Garrido, Alicia; Morais, Thiago; Barbosa, Juliana

    2013-01-01

    The present study investigates the arguments used by university students in order to explain social differences between social minorities and majorities. In Brazil, the issues investigated refer to White and Black people. In Spain, the reference is to native Spaniards and Moroccan immigrants. The participants were 144 Brazilians and 93 Spaniards, who answered a questionnaire composed of socio-demographic variables and one open question about the causes of social inequalities between Black and White people in Brazil and between autochthonous Spaniards and Moroccan Immigrants. A model is proposed to integrate the four discursive classes found using ALCESTE software. In Brazil, the strongest argument is based on the historical roots of the exploitation of Black people. In Spain, cultural differences are the main explanation for social inequalities.

  13. Rhythmic Degradation Explains and Unifies Circadian Transcriptome and Proteome Data

    Directory of Open Access Journals (Sweden)

    Sarah Lück

    2014-10-01

    Full Text Available The rich mammalian cellular circadian output affects thousands of genes in many cell types and has been the subject of genome-wide transcriptome and proteome studies. The results have been enigmatic because transcript peak abundances do not always follow the peaks of gene-expression activity in time. We posited that circadian degradation of mRNAs and proteins plays a pivotal role in setting their peak times. To establish guiding principles, we derived a theoretical framework that fully describes the amplitudes and phases of biomolecules with circadian half-lives. We were able to explain the circadian transcriptome and proteome studies with the same unifying theory, including cases in which transcripts or proteins appeared before the onset of increased production rates. Furthermore, we estimate that 30% of the circadian transcripts in mouse liver and Drosophila heads are affected by rhythmic posttranscriptional regulation.

  14. Visual Representation Determines Search Difficulty: Explaining Visual Search Asymmetries

    Directory of Open Access Journals (Sweden)

    Neil eBruce

    2011-07-01

    Full Text Available In visual search experiments there exist a variety of experimental paradigms in which a symmetric set of experimental conditions yields asymmetric corresponding task performance. There are a variety of examples of this that currently lack a satisfactory explanation. In this paper, we demonstrate that distinct classes of asymmetries may be explained by virtue of a few simple conditions that are consistent with current thinking surrounding computational modeling of visual search and coding in the primate brain. This includes a detailed look at the role that stimulus familiarity plays in the determination of search performance. Overall, we demonstrate that all of these asymmetries have a common origin, namely, they are a consequence of the encoding that appears in the visual cortex. The analysis associated with these cases yields insight into the problem of visual search in general and predictions of novel search asymmetries.

  15. Explaining drug policy: Towards an historical sociology of policy change.

    Science.gov (United States)

    Seddon, Toby

    2011-11-01

    The goal of seeking to understand the development over time of drug policies is a specific version of the more general intellectual project of finding ways of explaining social change. The latter has been a preoccupation of some of the greatest thinkers within the social sciences of the last 200 years, from Foucault all the way back to the three nineteenth-century pioneers, Marx, Durkheim and Weber. I describe this body of work as 'historical sociology'. In this paper, I outline how a particular approach to historical sociology can be fruitfully drawn upon to understand the development of drug policy, using by way of illustration the example of the analysis of a recent transformation in British drug policy: the rise of the criminal justice agenda. I conclude by arguing that by looking at developments in drug policy in this way, some new insights are opened up. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Explaining international co-authorship in global environmental change research

    Energy Technology Data Exchange (ETDEWEB)

    Jappe, A.

    2006-04-15

    This paper maps the domain of earth and environmental sciences (EES) and investigates the relationship between cognitive problem structures and internationalisation patterns, drawing on the concepts of systemic versus cumulative global environmental change (GEC) and mutual task dependence in scientific fields. We find that scientific output concentration and internationalisation are significantly higher in the systemic GEC fields of Meteorology and Atmospheric Sciences and Oceanography than in the cumulative GEC fields Ecology and Water Resources. The relationship is explained by stronger mutual task dependence in systemic GEC fields. In contrast, the portion of co-authorships with developing, emerging and transition countries among all international publications is larger for Water Resources than for the three other fields, consistent with the most pressing needs for STI capacity development in these countries. (orig.)

  17. Microeconomic principles explain an optimal genome size in bacteria.

    Science.gov (United States)

    Ranea, Juan A G; Grant, Alastair; Thornton, Janet M; Orengo, Christine A

    2005-01-01

    Bacteria can clearly enhance their survival by expanding their genetic repertoire. However, the tight packing of the bacterial genome and the fact that the most evolved species do not necessarily have the biggest genomes suggest there are other evolutionary factors limiting their genome expansion. To clarify these restrictions on size, we studied those protein families contributing most significantly to bacterial-genome complexity. We found that all bacteria apply the same basic and ancestral 'molecular technology' to optimize their reproductive efficiency. The same microeconomics principles that define the optimum size in a factory can also explain the existence of a statistical optimum in bacterial genome size. This optimum is reached when the bacterial genome obtains the maximum metabolic complexity (revenue) for minimal regulatory genes (logistic cost).

  18. Can sustained arousal explain the Chronic Fatigue Syndrome?

    Directory of Open Access Journals (Sweden)

    Eriksen Hege R

    2009-02-01

    Full Text Available Abstract We present an integrative model of disease mechanisms in the Chronic Fatigue Syndrome (CFS, unifying empirical findings from different research traditions. Based upon the Cognitive activation theory of stress (CATS, we argue that new data on cardiovascular and thermoregulatory regulation indicate a state of permanent arousal responses – sustained arousal – in this condition. We suggest that sustained arousal can originate from different precipitating factors (infections, psychosocial challenges interacting with predisposing factors (genetic traits, personality and learned expectancies (classical and operant conditioning. Furthermore, sustained arousal may explain documented alterations by establishing vicious circles within immunology (Th2 (humoral vs Th1 (cellular predominance, endocrinology (attenuated HPA axis, skeletal muscle function (attenuated cortical activation, increased oxidative stress and cognition (impaired memory and information processing. Finally, we propose a causal link between sustained arousal and the experience of fatigue. The model of sustained arousal embraces all main findings concerning CFS disease mechanisms within one theoretical framework.

  19. Amplitude saturation of MEMS resonators explained by autoparametric resonance

    International Nuclear Information System (INIS)

    Van der Avoort, C; Bontemps, J J M; Steeneken, P G; Le Phan, K; Van Beek, J T M; Van der Hout, R; Hulshof, J; Fey, R H B

    2010-01-01

    This paper describes a phenomenon that limits the power handling of MEMS resonators. It is observed that above a certain driving level, the resonance amplitude becomes independent of the driving level. In contrast to previous studies of power handling of MEMS resonators, it is found that this amplitude saturation cannot be explained by nonlinear terms in the spring constant or electrostatic force. Instead we show that the amplitude in our experiments is limited by nonlinear terms in the equation of motion which couple the in-plane length-extensional resonance mode to one or more out-of-plane (OOP) bending modes. We present experimental evidence for the autoparametric excitation of these OOP modes using a vibrometer. The measurements are compared to a model that can be used to predict a power-handling limit for MEMS resonators

  20. Muon-Induced Neutrons Do Not Explain the DAMA Data.

    Science.gov (United States)

    Klinger, J; Kudryavtsev, V A

    2015-04-17

    We present an accurate model of the muon-induced background in the DAMA/LIBRA experiment. Our work challenges proposed mechanisms which seek to explain the observed DAMA signal modulation with muon-induced backgrounds. Muon generation and transport are performed using the MUSIC/MUSUN code, and subsequent interactions in the vicinity of the DAMA detector cavern are simulated with Geant4. We estimate the total muon-induced neutron flux in the detector cavern to be Φ(n)(ν)=1.0 × 10(-9)  cm(-2) s(-1). We predict 3.49 × 10(-5)  counts/day/kg/keV, which accounts for less than 0.3% of the DAMA signal modulation amplitude.

  1. Once upon an algorithm how stories explain computing

    CERN Document Server

    Erwig, Martin

    2017-01-01

    How Hansel and Gretel, Sherlock Holmes, the movie Groundhog Day, Harry Potter, and other familiar stories illustrate the concepts of computing. Picture a computer scientist, staring at a screen and clicking away frantically on a keyboard, hacking into a system, or perhaps developing an app. Now delete that picture. In Once Upon an Algorithm, Martin Erwig explains computation as something that takes place beyond electronic computers, and computer science as the study of systematic problem solving. Erwig points out that many daily activities involve problem solving. Getting up in the morning, for example: You get up, take a shower, get dressed, eat breakfast. This simple daily routine solves a recurring problem through a series of well-defined steps. In computer science, such a routine is called an algorithm. Erwig illustrates a series of concepts in computing with examples from daily life and familiar stories. Hansel and Gretel, for example, execute an algorithm to get home from the forest. The movie Groundho...

  2. The Cholodny-Went theory does not explain hydrotropism.

    Science.gov (United States)

    Shkolnik, Doron; Fromm, Hillel

    2016-11-01

    Optimization of water foraging by plants is partially achieved by the ability of roots to direct growth towards high water potential, a phenomenon termed hydrotropism. In contrast to gravitropism and phototropism, which require auxin redistribution, as suggested by the Cholodny-Went theory, hydrotropism is not mediated by the phytohormone auxin, which raises questions about the mechanism underlying this tropic response. Here we specify the open questions in this field of research and discuss the possible interactions of abscisic acid, calcium and reactive oxygen species as part of a dynamic system of sensing water potential in the root tip, transmission of the signal to the root elongation zone and promoting root curvature towards water. We conclude that root hydrotropism is mediated by inter-cellular signals that are not explained by the Cholodny-Went theory. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Explaining the Pattern of CSDP-Operations: Towards a Theoretical Synthesis

    Directory of Open Access Journals (Sweden)

    Tim Haesebrouck

    2015-06-01

    Full Text Available The EU’s Common Security and Defence Policy (CSDP has mainly been used to deploy small-scale operations, which generally did not provide the member states with clear security benefits. This article combines insights from different theories of international relations to explain this disappointing track record. It argues that liberal theories adequately identify the domestic pressures the member states’ governments need to accommodate in the area of crisis management. Constructivism, on its part, properly emphasises the diverging strategic cultures of the member states. Both theories however fail to explain why domestic pressures and diverging strategic cultures lead to small-scale operations. Rational-choice institutionalism does provide a convincing explanation for the latter by drawing attention to the CSDP’s ineffective institutional design. Realism, in turn, is best positioned to explain why the CSDP was not designed more effectively, by emphasising the reluctance of states to transfer sovereignty to international organisations. The article concludes by discussing two measures that could alleviate the impact of the identified impediments on the CSDP’s track record: devising a CSDP-strategy and adapting the consensus rule. However, since the latter is very unlikely in the near future, the CSDP is not expected to develop into a more effective framework for crisis management.

  4. A theory with consolidation: Linking everything to explain everything

    Science.gov (United States)

    Biraris, Gaurav Shantaram

    The paper reports a theory which gives explicit (ontic) understanding of the abstract (epistemic) mechanisms spanning many branches of physics. It results to most modern physics starting from Newtonian physics by abandoning progress in twentieth century. The theory assumes consolidation of points in 4-balls of specific radius in the universe. Thus the 4-balls are fundamental elements of the universe. Analogue of momentum defined as soul vector is assumed to be induced on the 4-balls at the beginning of the universe. Then with progression of local time, collisions happen leading to different rotations of CNs. For such rotations, the consolidation provides centripetal binding. By using general terminologies of force and work, the mass energy mechanism gets revealed. The theory provides explicit interpretation of intrinsic properties of mass, electric charge, color charge, weak charge, spin etc. It also provides explicit understanding of the wave-particle duality & quantum mechanics. Epistemic study of the universe with the consolidation results to conventional quantum theories. Elementary mechanism of the field interactions is evident due to conservation of the soul vectors, and its epistemic expectation results to the gauge theories. The theory predicts that four types of interaction would exist in the universe along with the acceptable relative strengths; it provides fundamental interpretation of the physical forces. Further, it explains the basic mechanisms which can be identified with dark energy & dark matter. It also results to (or explains) entanglement, chirality, excess of matter, 4-component spinor, real-abstract (ontic-epistemic) correspondence etc. The theory is beyond standard model and results to the standard model, relativity, dark energy & dark matter, starting by simple assumptions.

  5. Strange history: the fall of Rome explained in Hereditas.

    Science.gov (United States)

    Bengtsson, Bengt O

    2014-12-01

    In 1921 Hereditas published an article on the fall of Rome written by the famous classical scholar Martin P:son Nilsson. Why was a paper on this unexpected topic printed in the newly founded journal? To Nilsson, the demise of the Roman Empire was explained by the "bastardization" occurring between "races" from different parts of the realm. Offspring from mixed couples were of a less stable "type" than their parents, due to the breaking up by recombination of the original hereditary dispositions, which led to a general loss of competence to rule and govern. Thus, the "hardness" of human genes, together with their recombination, was - according to Nilsson - the main cause of the fall of Rome. Nilsson's argument is not particularly convincingly presented. Human "races" are taken to have the same genetic structure as inbred crop strains, and Nilsson believes in a metaphysical unity between the individual and the race to which it belongs. However, in my view, Martin P:son Nilsson and his friend Herman Nilsson-Ehle had wider aims with the article than to explain a historical event. The article can be read as indicating strong support from the classical human sciences to the ambitious new science of genetics. Support is also transferred from genetics to the conservative worldview, where the immutability and inflexibility of the Mendelian genes are used to strengthen the wish for greater stability in politics and life. The strange article in Hereditas can, thus, be read as an early instance in the - still ongoing - tug-of-war between the conservative and the liberal ideological poles over how genetic results best are socially interpreted. © 2015 The Authors.

  6. A theory with consolidation: Linking everything to explain everything

    Directory of Open Access Journals (Sweden)

    Gaurav Shantaram Biraris

    Full Text Available The paper reports a theory which gives explicit (ontic understanding of the abstract (epistemic mechanisms spanning many branches of physics. It results to most modern physics starting from Newtonian physics by abandoning progress in twentieth century. The theory assumes consolidation of points in 4-balls of specific radius in the universe. Thus the 4-balls are fundamental elements of the universe. Analogue of momentum defined as soul vector is assumed to be induced on the 4-balls at the beginning of the universe. Then with progression of local time, collisions happen leading to different rotations of CNs. For such rotations, the consolidation provides centripetal binding. By using general terminologies of force and work, the mass energy mechanism gets revealed. The theory provides explicit interpretation of intrinsic properties of mass, electric charge, color charge, weak charge, spin etc. It also provides explicit understanding of the wave-particle duality & quantum mechanics. Epistemic study of the universe with the consolidation results to conventional quantum theories. Elementary mechanism of the field interactions is evident due to conservation of the soul vectors, and its epistemic expectation results to the gauge theories. The theory predicts that four types of interaction would exist in the universe along with the acceptable relative strengths; it provides fundamental interpretation of the physical forces. Further, it explains the basic mechanisms which can be identified with dark energy & dark matter. It also results to (or explains entanglement, chirality, excess of matter, 4-component spinor, real-abstract (ontic-epistemic correspondence etc. The theory is beyond standard model and results to the standard model, relativity, dark energy & dark matter, starting by simple assumptions. Keywords: Beyond standard model, Phenomenology, Relativity, Dark matter, Realist theory

  7. Explaining the Higgs decays at the LHC with an extended electroweak model

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Alexandre; Ramirez Barreto, E.; Dias, A. G.; de S. Pires, C. A.; Queiroz, Farinaldo S.; Rodrigues da Silva, P. S.

    2013-02-01

    We show that the observed enhancement in the diphoton decays of the recently discovered new boson at the LHC, which we assume to be a Higgs boson, can be naturally explained by a new doublet of charged vector bosons from extended electroweak models with SU(3)( )C( )ⓍSU(3)( )L( )ⓍU(1)( )X symmetry. These models are also rather economical in explaining the measured signal strengths, within the current experimental errors, demanding fewer assumptions and less parameters tuning. Our results show a good agreement between the theoretical expected sensitivity to a 126–125 GeV Higgs boson, and the experimental significance observed in the diphoton channel at the 8 TeV LHC. Effects of an invisible decay channel for the Higgs boson are also taken into account, in order to anticipate a possible confirmation of deficits in the branching ratios into ZZ (*), WW (*), bottom quarks, and tau leptons.

  8. Answering questions and explaining answers: a study of Finnish-speaking children.

    Science.gov (United States)

    Loukusa, Soile; Ryder, Nuala; Leinonen, Eeva

    2008-05-01

    This research explores, within the framework of Relevance Theory, how children's ability to answer questions and explain their answers develops between the ages of 3 and 9 years. Two hundred and ten normally developing Finnish-speaking children participated in this study. The children were asked questions requiring processing of inferential meanings and routines, and were asked to explain their correct answers to elicit understanding about their awareness of how they had derived the answers from the context. The results indicated that the number of correct answers increased rapidly between the ages of 3 years and 4-5 years. Familiarity of context had a significant effect on young children's ability to answer questions. Becoming aware of the information used in inferencing developed gradually over time between the ages of 3 and 9. Analysis of the children's incorrect answers and explanations showed that, as children develop, their unsophisticated answer strategies diminish and they increasingly utilize context even in incorrect answers and explanations.

  9. Can a microscopic stochastic model explain the emergence of pain cycles in patients?

    International Nuclear Information System (INIS)

    Di Patti, Francesca; Fanelli, Duccio

    2009-01-01

    A stochastic model is introduced here to investigate the molecular mechanisms which trigger the perception of pain. The action of analgesic drug compounds is discussed in a dynamical context, where the competition with inactive species is explicitly accounted for. Finite size effects inevitably perturb the mean-field dynamics: oscillations in the amount of bound receptors are spontaneously manifested, driven by the noise which is intrinsic to the system under scrutiny. These effects are investigated both numerically, via stochastic simulations, and analytically, through a large size expansion. The claim that our findings could provide a consistent interpretative framework for explaining the emergence of cyclic behaviors in response to analgesic treatments is substantiated

  10. Climate and Human Pressure Constraints Co-Explain Regional Plant Invasion at Different Spatial Scales.

    Science.gov (United States)

    Campos, Juan Antonio; García-Baquero, Gonzalo; Caño, Lidia; Biurrun, Idoia; García-Mijangos, Itziar; Loidi, Javier; Herrera, Mercedes

    2016-01-01

    Alien species invasion represents a global threat to biodiversity and ecosystems. Explaining invasion patterns in terms of environmental constraints will help us to assess invasion risks and plan control strategies. We aim to identify plant invasion patterns in the Basque Country (Spain), and to determine the effects of climate and human pressure on that pattern. We modeled the regional distribution of 89 invasive plant species using two approaches. First, distance-based Moran's eigenvector maps were used to partition variation in the invasive species richness, S, into spatial components at broad and fine scales; redundancy analysis was then used to explain those components on the basis of climate and human pressure descriptors. Second, we used generalized additive mixed modeling to fit species-specific responses to the same descriptors. Climate and human pressure descriptors have different effects on S at different spatial scales. Broad-scale spatially structured temperature and precipitation, and fine-scale spatially structured human population density and percentage of natural and semi-natural areas, explained altogether 38.7% of the total variance. The distribution of 84% of the individually tested species was related to either temperature, precipitation or both, and 68% was related to either population density or natural and semi-natural areas, displaying similar responses. The spatial pattern of the invasive species richness is strongly environmentally forced, mainly by climate factors. Since individual species responses were proved to be both similarly constrained in shape and explained variance by the same environmental factors, we conclude that the pattern of invasive species richness results from individual species' environmental preferences.

  11. Buzz Factor or Innovation Potential: What Explains Cryptocurrencies' Returns?

    Directory of Open Access Journals (Sweden)

    Sha Wang

    Full Text Available Cryptocurrencies have become increasingly popular since the introduction of bitcoin in 2009. In this paper, we identify factors associated with variations in cryptocurrencies' market values. In the past, researchers argued that the "buzz" surrounding cryptocurrencies in online media explained their price variations. But this observation obfuscates the notion that cryptocurrencies, unlike fiat currencies, are technologies entailing a true innovation potential. By using, for the first time, a unique measure of innovation potential, we find that the latter is in fact the most important factor associated with increases in cryptocurrency returns. By contrast, we find that the buzz surrounding cryptocurrencies is negatively associated with returns after controlling for a variety of factors, such as supply growth and liquidity. Also interesting is our finding that a cryptocurrency's association with fraudulent activity is not negatively associated with weekly returns-a result that further qualifies the media's influence on cryptocurrencies. Finally, we find that an increase in supply is positively associated with weekly returns. Taken together, our findings show that cryptocurrencies do not behave like traditional currencies or commodities-unlike what most prior research has assumed-and depict an industry that is much more mature, and much less speculative, than has been implied by previous accounts.

  12. A Bullet-Block Experiment that Explains the Chain Fountain

    Science.gov (United States)

    Pantaleone, J.; Smith, R.

    2018-05-01

    It is common in science for two phenomena to appear to be very different, but in fact follow from the same basic principles. Here we consider such a case, the connection between the chain fountain and a bullet-block collision experiment. When an upward moving bullet strikes a wooden block resting on a horizontal table, the block will rise to a higher height when the bullet strikes near the end of the block. This is because the quickly rotating block experiences an additional upward "reaction" force from its contact with the table. Such a reaction force also explains the chain fountain. When a chain falls from a pile in a container to the floor below, the chain rises up above the container. This rise occurs because the quickly rotating links in the container push off of the surface beneath them. We derive a model that accurately describes our measurements in the bullet-block experiment, and then use this same model to calculate an approximate expression for the distance the chain rises above the container. More extensive discussions of the chain fountain are available elsewhere.

  13. Global patterns in endemism explained by past climatic change.

    Science.gov (United States)

    Jansson, Roland

    2003-03-22

    I propose that global patterns in numbers of range-restricted endemic species are caused by variation in the amplitude of climatic change occurring on time-scales of 10-100 thousand years (Milankovitch oscillations). The smaller the climatic shifts, the more probable it is that palaeoendemics survive and that diverging gene pools persist without going extinct or merging, favouring the evolution of neoendemics. Using the change in mean annual temperature since the last glacial maximum, estimated from global circulation models, I show that the higher the temperature change in an area, the fewer endemic species of mammals, birds, reptiles, amphibians and vascular plants it harbours. This relationship was robust to variation in area (for areas greater than 10(4) km2), latitudinal position, extent of former glaciation and whether or not areas are oceanic islands. Past climatic change was a better predictor of endemism than annual temperature range in all phylads except amphibians, suggesting that Rapoport's rule (i.e. species range sizes increase with latitude) is best explained by the increase in the amplitude of climatic oscillations towards the poles. Globally, endemic-rich areas are predicted to warm less in response to greenhouse-gas emissions, but the predicted warming would cause many habitats to disappear regionally, leading to species extinctions.

  14. Glacial ocean circulation and stratification explained by reduced atmospheric temperature.

    Science.gov (United States)

    Jansen, Malte F

    2017-01-03

    Earth's climate has undergone dramatic shifts between glacial and interglacial time periods, with high-latitude temperature changes on the order of 5-10 °C. These climatic shifts have been associated with major rearrangements in the deep ocean circulation and stratification, which have likely played an important role in the observed atmospheric carbon dioxide swings by affecting the partitioning of carbon between the atmosphere and the ocean. The mechanisms by which the deep ocean circulation changed, however, are still unclear and represent a major challenge to our understanding of glacial climates. This study shows that various inferred changes in the deep ocean circulation and stratification between glacial and interglacial climates can be interpreted as a direct consequence of atmospheric temperature differences. Colder atmospheric temperatures lead to increased sea ice cover and formation rate around Antarctica. The associated enhanced brine rejection leads to a strongly increased deep ocean stratification, consistent with high abyssal salinities inferred for the last glacial maximum. The increased stratification goes together with a weakening and shoaling of the interhemispheric overturning circulation, again consistent with proxy evidence for the last glacial. The shallower interhemispheric overturning circulation makes room for slowly moving water of Antarctic origin, which explains the observed middepth radiocarbon age maximum and may play an important role in ocean carbon storage.

  15. Major Gravitational Phenomena Explained by the Micro-Quanta Paradigm

    Directory of Open Access Journals (Sweden)

    Michelini M.

    2010-01-01

    Full Text Available Some major problems of physics, which remained unsolved within classical and rel- ativistic gravitation theories, are explained adopting the quantum gravity interaction descending from the micro-quanta paradigm. The energy source of the gravitational power P g r , which heats and contracts the Bok’s gas globules harbouring the future stars, is identified and defined as well as the gravitational power generated on the solid / fluid planets. Calculations are carried out to make the comparison between P g r predicted for the solar giant planets and the measured infrared radiation power P int coming from the interior. The case of planets with solid crust (Earth, etc. requires a particular attention due to the threat to stability produced by the thermal dilatation. An analysis is done of the Earth’s planetary equilibrium which may be attained eliminating the temperature rise through the migration of hot internal magma across the crust fractured by earth- quakes. The temperatures observed up to 420,000 years ago in Antartica through Vostok and Epica ice cores suggest the possibility that the Earth gravitational power P g r may be radiated in space through these temperature cycles (Glacial Eras. In this general frame the Earth’s high seismicity and the dynamics of Plate tectonics may find their origin.

  16. Major Gravitational Phenomena Explained by the Micro-Quanta Paradigm

    Directory of Open Access Journals (Sweden)

    Michelini M.

    2010-01-01

    Full Text Available Some major problems of physics, which remained unsolved within classical and relativistic gravitation theories, are explained adopting the quantum gravity interaction descending from the micro-quanta paradigm. The energy source of the gravitational power $P_{gr}$, which heats and contracts the Bok's gas globules harbouring the future stars, is identified and defined as well as the gravitational power generated on the solid/fluid planets. Calculations are carried out to make the comparison between $P_{gr}$ predicted for the solar giant planets and the measured infrared radiation power $P_{int}$ coming from the interior. The case of planets with solid crust (Earth, etc. requires a particular attention due to the threat to stability produced by the thermal dilatation. An analysis is done of the Earth's planetary equilibrium which may be attained eliminating the temperature rise through the migration of hot internal magma across the crust fractured by earthquakes. The temperatures observed up to 420,000 years ago in Antartica through Vostok and Epica ice cores suggest the possibility that the Earth gravitational power $P_{gr}$ may be radiated in space through these temperature cycles (Glacial Eras. In this general frame the Earth's high seismicity and the dynamics of Plate tectonics may find their origin.

  17. Buzz Factor or Innovation Potential: What Explains Cryptocurrencies' Returns?

    Science.gov (United States)

    Wang, Sha; Vergne, Jean-Philippe

    2017-01-01

    Cryptocurrencies have become increasingly popular since the introduction of bitcoin in 2009. In this paper, we identify factors associated with variations in cryptocurrencies' market values. In the past, researchers argued that the "buzz" surrounding cryptocurrencies in online media explained their price variations. But this observation obfuscates the notion that cryptocurrencies, unlike fiat currencies, are technologies entailing a true innovation potential. By using, for the first time, a unique measure of innovation potential, we find that the latter is in fact the most important factor associated with increases in cryptocurrency returns. By contrast, we find that the buzz surrounding cryptocurrencies is negatively associated with returns after controlling for a variety of factors, such as supply growth and liquidity. Also interesting is our finding that a cryptocurrency's association with fraudulent activity is not negatively associated with weekly returns-a result that further qualifies the media's influence on cryptocurrencies. Finally, we find that an increase in supply is positively associated with weekly returns. Taken together, our findings show that cryptocurrencies do not behave like traditional currencies or commodities-unlike what most prior research has assumed-and depict an industry that is much more mature, and much less speculative, than has been implied by previous accounts.

  18. Buzz Factor or Innovation Potential: What Explains Cryptocurrencies’ Returns?

    Science.gov (United States)

    Wang, Sha

    2017-01-01

    Cryptocurrencies have become increasingly popular since the introduction of bitcoin in 2009. In this paper, we identify factors associated with variations in cryptocurrencies’ market values. In the past, researchers argued that the “buzz” surrounding cryptocurrencies in online media explained their price variations. But this observation obfuscates the notion that cryptocurrencies, unlike fiat currencies, are technologies entailing a true innovation potential. By using, for the first time, a unique measure of innovation potential, we find that the latter is in fact the most important factor associated with increases in cryptocurrency returns. By contrast, we find that the buzz surrounding cryptocurrencies is negatively associated with returns after controlling for a variety of factors, such as supply growth and liquidity. Also interesting is our finding that a cryptocurrency’s association with fraudulent activity is not negatively associated with weekly returns—a result that further qualifies the media’s influence on cryptocurrencies. Finally, we find that an increase in supply is positively associated with weekly returns. Taken together, our findings show that cryptocurrencies do not behave like traditional currencies or commodities—unlike what most prior research has assumed—and depict an industry that is much more mature, and much less speculative, than has been implied by previous accounts. PMID:28085906

  19. Explaining the Association Between Music Training and Reading in Adults.

    Science.gov (United States)

    Swaminathan, Swathi; Schellenberg, E Glenn; Venkatesan, Kirthika

    2018-02-01

    We sought to clarify whether the positive association between music lessons and reading ability is explained better by shared resources for processing pitch and temporal information, or by general cognitive abilities. Participants were native and nonnative speakers of English with varying levels of music training. We measured reading ability (comprehension and speed), music-perception skills (melody and rhythm), general cognitive ability (nonverbal intelligence, short-term memory, and working memory), and socioeconomic status (SES; family income, parents' education). Reading ability was associated positively with music training, English as a native language, and general cognitive ability. The association between reading and music training was significant after SES, native language, and music-perception skills were controlled. After general cognitive abilities were held constant, however, there was no longer an association between reading and music training. These findings suggest that the association between reading ability and music training is a consequence of general cognitive abilities. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  20. Nest predation risk explains variation in avian clutch size

    Science.gov (United States)

    Dillon, Kristen G.; Conway, Courtney J.

    2018-01-01

    Questions about the ecological drivers of, and mechanistic constraints on, productivity have driven research on life-history evolution for decades. Resource availability and offspring mortality are considered among the 2 most important influences on the number of offspring per reproductive attempt. We used a factorial experimental design to manipulate food abundance and perceived offspring predation risk in a wild avian population (red-faced warblers; Cardellina rubrifrons) to identify the mechanistic cause of variation in avian clutch size. Additionally, we tested whether female quality helped explain the extant variation in clutch size. We found no support for the Food Limitation or Female Quality Hypotheses, but we did find support for both predictions of the Nest Predation Risk Hypothesis. Females that experienced an experimentally heightened perception of offspring predation risk responded by laying a smaller clutch than females in the control group. Additionally, predation rates at artificial nests were highest where red-faced warbler clutch size was smallest (at high elevations). Life-history theory predicts that an individual should invest less in reproduction when high nest predation risk reduces the likely benefit from that nesting attempt and, indeed, we found that birds exhibit phenotypic plasticity in clutch size by laying fewer eggs in response to increasing nest predation risk.

  1. [Explaining symptoms: body-object and body-subject].

    Science.gov (United States)

    ter, Meulen B C; Van Woerkom, T C A M

    2009-01-01

    Medically unexplained somatic symptoms present a real challenge to modem medicine. They occur frequently and are often chronic. To discuss the physician's approach to these symptoms. We focus on the views of the human body put forward by the French philosopher Merleau-Ponty. His view is illustrated with the help of a case study concerning a patient suffering from borderline personality disorder and complex regional pain syndrome. Merleau-Ponty draws a distinction between body-subject and body-object. By body-object he means the body as determined and predicted by medical science. By body-subject he means the body as we experience it, even before we are aware of it. It is our pre-reflexive body that gives meaning to the world around us. We argue that the physician should regard the body not only as an object, but also as a subject, thereby giving renewed attention to the significance of symptoms as an expression of inner experience. In this way symptoms that cannot be explained on a purely physico-chemical level will become more meaningful.

  2. Cultural values: can they explain self-reported health?

    Science.gov (United States)

    Roudijk, Bram; Donders, Rogier; Stalmeier, Peep

    2017-06-01

    Self-reported health (SRH) is a measure widely used in health research and population studies. Differences in SRH have been observed between countries and cultural values have been hypothesized to partly explain such differences. Cultural values can be operationalized by two cultural dimensions using the World Values Survey (WVS), namely the traditional/rational-secular and the survival/self-expression dimension. We investigate whether there is an association between the WVS cultural dimensions and SRH, both within and between countries. Data from 51 countries in the WVS is used and combined with macroeconomic data from the Worldbank database. The association between SRH and the WVS cultural dimensions is tested within each of the 51 countries and multilevel mixed models are used to test differences between these countries. Socio-demographic and macroeconomic variables are used to correct for non-cultural variables related to SRH. Within countries, the survival/self-expression dimension was positively associated with SRH, while in most countries there was a negative association for the traditional/rational-secular dimension. Values range between 4 and 17% within countries. Further analyses show that the associations within countries and between countries are similar. Controlling for macroeconomic and socio-demographic factors did not change our results. The WVS cultural dimensions predict SRH within and between countries. Contrary to our expectations, traditional/rational-secular values were negatively associated with SRH. As SRH is associated with cultural values between countries, cultural values could be considered when interpreting SRH between countries.

  3. Translucent Players: Explaining Cooperative Behavior in Social Dilemmas

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    Valerio Capraro

    2016-06-01

    Full Text Available In the last few decades, numerous experiments have shown that humans do not always behave so as to maximize their material payoff. Cooperative behavior when non-cooperation is a dominant strategy (with respect to the material payoffs is particularly puzzling. Here we propose a novel approach to explain cooperation, assuming what Halpern and Pass call translucent players. Typically, players are assumed to be opaque, in the sense that a deviation by one player in a normal-form game does not affect the strategies used by other players. But a player may believe that if he switches from one strategy to another, the fact that he chooses to switch may be visible to the other players. For example, if he chooses to defect in Prisoner's Dilemma, the other player may sense his guilt. We show that by assuming translucent players, we can recover many of the regularities observed in human behavior in well-studied games such as Prisoner's Dilemma, Traveler's Dilemma, Bertrand Competition, and the Public Goods game.

  4. Explaining History. Hippolyte Taine's Philosophy of Historical Science

    Science.gov (United States)

    Müller, Philipp

    Historians of European historiography have often characterized Hippolyte Taine (1828-1893) as an adherent of the positivist school of thought, typical for the development of a scientific culture in Western Europe that differed from its German counterpart.1 In accordance with that view, Wilhelm Dilthey grouped him together with other scholars like John Stuart Mill and Herbert Spencer against who Dilthey tried to develop his conception of the human sciences based on the notion of "verstehen" (see Dilthey [1924] 1957, 139ff.). Dilthey understood Taine as proposing to analyze the human mind by identifying its individual components and then explaining their meaning by laws of their relation. He argued that such an approach might be adequate for the natural sciences, but neglected the fact that an analysis of the mind had to start from a given psychological connection that was prior to any definition of particular phenomena. From Dilthey's point of view, applying Taine's theory to historical studies only made them look more objective while actually Taine was unaware of just following the prevailing convictions of his time (idem, 191f.).

  5. Classifying and explaining democracy in the Muslim world

    Directory of Open Access Journals (Sweden)

    Rohaizan Baharuddin

    2012-12-01

    Full Text Available The purpose of this study is to classify and explain democracies in the 47 Muslim countries between the years 1998 and 2008 by using liberties and elections as independent variables. Specifically focusing on the context of the Muslim world, this study examines the performance of civil liberties and elections, variation of democracy practised the most, the elections, civil liberties and democratic transitions and patterns that followed. Based on the quantitative data primarily collected from Freedom House, this study demonstrates the following aggregate findings: first, the “not free not fair” elections, the “limited” civil liberties and the “Illiberal Partial Democracy” were the dominant feature of elections, civil liberties and democracy practised in the Muslim world; second, a total of 413 Muslim regimes out of 470 (47 regimes x 10 years remained the same as their democratic origin points, without any transitions to a better or worse level of democracy, throughout these 10 years; and third, a slow, yet steady positive transition of both elections and civil liberties occurred in the Muslim world with changes in the nature of elections becoming much more progressive compared to the civil liberties’ transitions.

  6. Central venous oxygenation: when physiology explains apparent discrepancies.

    Science.gov (United States)

    Squara, Pierre

    2014-11-10

    Central venous oxygen saturation (ScvO2) >70% or mixed venous oxygen saturation (SvO2) >65% is recommended for both septic and non-septic patients. Although it is the task of experts to suggest clear and simple guidelines, there is a risk of reducing critical care to these simple recommendations. This article reviews the basic physiological and pathological features as well as the metrological issues that provide clear evidence that SvO2 and ScvO2 are adaptative variables with large inter-patient variability. This variability is exemplified in a modeled population of 1,000 standard ICU patients and in a real population of 100 patients including 15,860 measurements. In these populations, it can be seen how optimizing one to three of the four S(c)vO2 components homogenized the patients and yields a clear dependency with the fourth one. This explains the discordant results observed in large studies where cardiac output was increased up to predetermined S(c)vO2 thresholds following arterial oxygen hemoglobin saturation, total body oxygen consumption needs and hemoglobin optimization. Although a systematic S(c)vO2 goal-oriented protocol can be statistically profitable before ICU admission, appropriate intensive care mandates determination of the best compromise between S(c)vO2 and its four components, taking into account the specific constraints of each individual patient.

  7. A Conceptual Characterization of Online Videos Explaining Natural Selection

    Science.gov (United States)

    Bohlin, Gustav; Göransson, Andreas; Höst, Gunnar E.; Tibell, Lena A. E.

    2017-11-01

    Educational videos on the Internet comprise a vast and highly diverse source of information. Online search engines facilitate access to numerous videos claiming to explain natural selection, but little is known about the degree to which the video content match key evolutionary content identified as important in evolution education research. In this study, we therefore analyzed the content of 60 videos accessed through the Internet, using a criteria catalog with 38 operationalized variables derived from research literature. The variables were sorted into four categories: (a) key concepts (e.g. limited resources and inherited variation), (b) threshold concepts (abstract concepts with a transforming and integrative function), (c) misconceptions (e.g. that evolution is driven by need), and (d) organismal context (e.g. animal or plant). The results indicate that some concepts are frequently communicated, and certain taxa are commonly used to illustrate concepts, while others are seldom included. In addition, evolutionary phenomena at small temporal and spatial scales, such as subcellular processes, are rarely covered. Rather, the focus is on population-level events over time scales spanning years or longer. This is consistent with an observed lack of explanations regarding how randomly occurring mutations provide the basis for variation (and thus natural selection). The findings imply, among other things, that some components of natural selection warrant far more attention in biology teaching and science education research.

  8. Explaining inequalities in access to treatment in lung cancer.

    Science.gov (United States)

    Jack, Ruth H; Gulliford, Martin C; Ferguson, Jamie; Møller, Henrik

    2006-10-01

    Geographical inequalities in lung cancer treatment and patient survival have been described. We hypothesized that lung cancer patients' access to treatment may be influenced by deprivation and the pathway to care. Case notes were reviewed for patients resident in south-east London who were registered with lung cancer at the Thames Cancer Registry in 1998. Use of surgery, chemotherapy, radiotherapy or any specific treatment and one-year survival were examined. Analyses were adjusted for age, sex, histology, stage and basis of diagnosis. Data for 695 out of 958 (73%) patients were analysed. Subjects who were initially referred to a specialist in thoracic medicine, surgery or oncology were more likely to receive active treatment (71%) than subjects who were referred to other consultants (51%) or who were admitted as emergencies (42%) (P < 0.0001). Socio-economic deprivation was associated with lower rates of treatment and this partly explained variations in survival. Subjects who were referred to specialists were more likely to receive active treatment and treatment patterns varied between first trust attended.

  9. Puzzling features of western Mediterranean tectonics explained by slab dragging

    Science.gov (United States)

    Spakman, Wim; Chertova, Maria V.; van den Berg, Arie.; van Hinsbergen, Douwe J. J.

    2018-02-01

    The recent tectonic evolution of the western Mediterranean region is enigmatic. The causes for the closure of the Moroccan marine gateway prior to the Messinian salinity crisis, for the ongoing shortening of the Moroccan Rif and for the origin of the seismogenic Trans-Alboran shear zone and eastern Betics extension are unclear. These puzzling tectonic features cannot be fully explained by subduction of the east-dipping Gibraltar slab in the context of the regional relative plate motion frame. Here we use a combination of geological and geodetic data, as well as three-dimensional numerical modelling of subduction, to show that these unusual tectonic features could be the consequence of slab dragging—the north to north-eastward dragging of the Gibraltar slab by the absolute motion of the African Plate. Comparison of our model results to patterns of deformation in the western Mediterranean constrained by geological and geodetic data confirm that slab dragging provides a plausible mechanism for the observed deformation. Our results imply that the impact of absolute plate motion on subduction is identifiable from crustal observations. Identifying such signatures elsewhere may improve the mantle reference frame and provide insights on subduction evolution and associated crustal deformation.

  10. Fatal attraction: Explaining Russia's sensitive nuclear transfers to Iran

    Science.gov (United States)

    Kuchinsky, Leah R.

    This paper explores Russia's sensitive nuclear assistance to Iran in an effort to determine why a supplier state might proliferate against its own apparent security interests. The goal is to help readers understand the supply-side dynamics of nuclear proliferation. Through careful reconstruction of the historical narrative, using open source data, this study tests the plausibility of a "fatalistic calculus" explanation, identified by Stephen Sestanovich as a possible driver for Russia's behavior. According to the hypothesis, Russia has cooperated with Iran as a way both to stay in the good graces of a neighbor that is suspected of developing nuclear weapons and to win short-term influence and profits. The paper also examines the role of other factors advanced in the existing supply-side literature, such as economic motives identified by physicist and nonproliferation scholar David Albright. The findings show that bureaucratic, economic and fatalistic factors have each played a role in motivating Russia's cooperation with Iran, with their relative importance shifting over time. Fatalism begets a strategy of Russian "minimaxing," in the lexicon of Russia scholar Robert Freedman, wherein Russia attempts to minimize damage to its relationship with the U.S. while maximizing influence in Iran via nuclear cooperation. Fatalism, as actualized by minimaxing, best explains Russia's behavior after former Russian president Vladmir Putin came to power, when the bureaucratic and economic arguments become less cogent.

  11. Can mathematics explain the evolution of human language?

    Science.gov (United States)

    Witzany, Guenther

    2011-09-01

    Investigation into the sequence structure of the genetic code by means of an informatic approach is a real success story. The features of human language are also the object of investigation within the realm of formal language theories. They focus on the common rules of a universal grammar that lies behind all languages and determine generation of syntactic structures. This universal grammar is a depiction of material reality, i.e., the hidden logical order of things and its relations determined by natural laws. Therefore mathematics is viewed not only as an appropriate tool to investigate human language and genetic code structures through computer science-based formal language theory but is itself a depiction of material reality. This confusion between language as a scientific tool to describe observations/experiences within cognitive constructed models and formal language as a direct depiction of material reality occurs not only in current approaches but was the central focus of the philosophy of science debate in the twentieth century, with rather unexpected results. This article recalls these results and their implications for more recent mathematical approaches that also attempt to explain the evolution of human language.

  12. Exposure to environmental microbiota explains persistent abdominal pain and irritable bowel syndrome after a major flood.

    Science.gov (United States)

    Yusof, NurFadhilah; Hamid, Nurhazwani; Ma, Zheng Feei; Lawenko, Rona Marie; Wan Mohammad, Wan Mohd Zahiruddin; Collins, Deirdre A; Liong, Min Tze; Odamaki, Toshitaka; Xiao, Jinzhong; Lee, Yeong Yeh

    2017-01-01

    After an environmental disaster, the affected community is at increased risk for persistent abdominal pain but mechanisms are unclear. Therefore, our study aimed to determine association between abdominal pain and poor water, sanitation and hygiene (WaSH) practices, and if small intestinal bacterial overgrowth (SIBO) and/or gut dysbiosis explain IBS, impaired quality of life (QOL), anxiety and/or depression after a major flood. New onset abdominal pain, IBS based on the Rome III criteria, WaSH practices, QOL, anxiety and/or depression, SIBO (hydrogen breath testing) and stools for metagenomic sequencing were assessed in flood victims. Of 211 participants, 37.9% ( n  = 80) had abdominal pain and 17% ( n  = 36) with IBS subtyped diarrhea and/or mixed type ( n  = 27 or 12.8%) being the most common. Poor WaSH practices and impaired quality of life during flood were significantly associated with IBS. Using linear discriminant analysis effect size method, gut dysbiosis was observed in those with anxiety (Bacteroidetes and Proteobacteria, effect size 4.8), abdominal pain (Fusobacteria , Staphylococcus, Megamonas and Plesiomonas , effect size 4.0) and IBS ( Plesiomonas and Trabulsiella , effect size 3.0). Disturbed gut microbiota because of environmentally-derived organisms may explain persistent abdominal pain and IBS after a major environmental disaster in the presence of poor WaSH practices.

  13. The Amazon River reversal explained by tectonic and surface processes

    Science.gov (United States)

    Sacek, V.

    2014-12-01

    The drainage pattern in Amazonia was expressively modified during the mountain building of central and northern Andes. In Early Miocene, the fluvial systems in western Amazonia flowed to the foreland basins and northward to the Caribbean. By Late Miocene the drainage reversal occurred and formed the transcontinental Amazon River, connecting the Andes and the equatorial Atlantic margin. This event is recorded in the stratigraphic evolution of the Foz do Amazonas Basin by the onset of Andean-derived sedimentation. Additionally, an abrupt increase in sedimentation rate after the reversal occurred in the Foz do Amazonas Basin. Based on three-dimensional numerical models that couple surface processes, flexural isostasy and crustal thickening due to orogeny, I concluded that the Miocene drainage reversal can be explained by the flexural and surface processes response to the Andes formation with no need to invoke dynamic topography induced by mantle convection, as previously proposed. I observed that the instant of drainage reversal is directly linked to the rate of crustal thickening in the orogeny, the rate of erosion and, mainly, the efficiency of sediment transport. Moreover, the numerical experiments were able to predict the increase in sedimentation rate in the Amazon fan after the drainage reversal of the Amazon River as observed in the Late Miocene-Pliocene sedimentary record. However, the present numerical model fails to fully reproduce the evolution of the Pebas system, a megawetland in western Amazonia that preceded the drainage reversal. Therefore, further investigation is necessary to evaluate the mechanisms that generated and sustained the Pebas system.

  14. Explaining the imperfection of the molecular clock of hominid mitochondria.

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    Eva-Liis Loogväli

    Full Text Available The molecular clock of mitochondrial DNA has been extensively used to date various genetic events. However, its substitution rate among humans appears to be higher than rates inferred from human-chimpanzee comparisons, limiting the potential of interspecies clock calibrations for intraspecific dating. It is not well understood how and why the substitution rate accelerates. We have analyzed a phylogenetic tree of 3057 publicly available human mitochondrial DNA coding region sequences for changes in the ratios of mutations belonging to different functional classes. The proportion of non-synonymous and RNA genes substitutions has reduced over hundreds of thousands of years. The highest mutation ratios corresponding to fast acceleration in the apparent substitution rate of the coding sequence have occurred after the end of the Last Ice Age. We recalibrate the molecular clock of human mtDNA as 7990 years per synonymous mutation over the mitochondrial genome. However, the distribution of substitutions at synonymous sites in human data significantly departs from a model assuming a single rate parameter and implies at least 3 different subclasses of sites. Neutral model with 3 synonymous substitution rates can explain most, if not all, of the apparent molecular clock difference between the intra- and interspecies levels. Our findings imply the sluggishness of purifying selection in removing the slightly deleterious mutations from the human as well as the Neandertal and chimpanzee populations. However, for humans, the weakness of purifying selection has been further exacerbated by the population expansions associated with the out-of Africa migration and the end of the Last Ice Age.

  15. THE CONTEMPORARY METHODOLOGICAL APPROACHES AND THEORIES EXPLAINING INTERNATIONAL TOURISM FLOWS

    Directory of Open Access Journals (Sweden)

    Zorina SISCAN

    2017-08-01

    Full Text Available Proceeding from the fact that international tourism is in permanent growth the last decades, and contributes signi­ficantly to the development of contemporary national economies, the authors of the article have focused on methodo­logical and theoretical frame that allows deeper understanding of the touristic flows from various aspects. In doing so, the first author has launched some methodological approaches that allow deepening a perspective research on touristic flows while the second author has concentrated upon grouping and analysis of existing theories used to explain touristic flows. As an outcome, the authors recommend a blend of those approaches and theories to be used for an adequate understanding and managing the existing and perspective touristic flows.ABORDDĂRI METODOLOGICE ȘI TEORII CONTEMPORANE CARE EXPLICĂ FLUXURILE DE TURISM INTERNAȚIONALPornind de la faptul că turismul internațional manifestă permanentă creștere în ultimele decenii, precum și contribuie semnificativ la dezvoltarea economiilor naționale contemporane, autorii articolului s-au axat pe cadrul metodologic și teoretic ce ar permite conceperea aprofundată a fluxurilor de turism internațional. Primul autor a lansat unele abordări metodologice care ar contribui la aprofundarea cercetărilor de perspectivă ale fluxurilor turistice, iar cel de-al doilea autor și-a concentrat atenția asupra grupării și analizei teoriilor existente în care se explică natura fluxurilor de turism. Ca rezultat, autorii recomandă utilizarea îmbinării organice a abordărilor și teoriilor considerate pentru perceperea și gestionarea adecvată a fluxurilor de turism existente și de perspectivă.

  16. An explainable deep machine vision framework for plant stress phenotyping.

    Science.gov (United States)

    Ghosal, Sambuddha; Blystone, David; Singh, Asheesh K; Ganapathysubramanian, Baskar; Singh, Arti; Sarkar, Soumik

    2018-04-16

    Current approaches for accurate identification, classification, and quantification of biotic and abiotic stresses in crop research and production are predominantly visual and require specialized training. However, such techniques are hindered by subjectivity resulting from inter- and intrarater cognitive variability. This translates to erroneous decisions and a significant waste of resources. Here, we demonstrate a machine learning framework's ability to identify and classify a diverse set of foliar stresses in soybean [ Glycine max (L.) Merr.] with remarkable accuracy. We also present an explanation mechanism, using the top-K high-resolution feature maps that isolate the visual symptoms used to make predictions. This unsupervised identification of visual symptoms provides a quantitative measure of stress severity, allowing for identification (type of foliar stress), classification (low, medium, or high stress), and quantification (stress severity) in a single framework without detailed symptom annotation by experts. We reliably identified and classified several biotic (bacterial and fungal diseases) and abiotic (chemical injury and nutrient deficiency) stresses by learning from over 25,000 images. The learned model is robust to input image perturbations, demonstrating viability for high-throughput deployment. We also noticed that the learned model appears to be agnostic to species, seemingly demonstrating an ability of transfer learning. The availability of an explainable model that can consistently, rapidly, and accurately identify and quantify foliar stresses would have significant implications in scientific research, plant breeding, and crop production. The trained model could be deployed in mobile platforms (e.g., unmanned air vehicles and automated ground scouts) for rapid, large-scale scouting or as a mobile application for real-time detection of stress by farmers and researchers. Copyright © 2018 the Author(s). Published by PNAS.

  17. RNA silencing can explain chlorotic infection patterns on plant leaves

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    Hogeweg Paulien

    2008-11-01

    Full Text Available Abstract Background RNA silencing has been implicated in virus symptom development in plants. One common infection symptom in plants is the formation of chlorotic tissue in leaves. Chlorotic and healthy tissue co-occur on a single leaf and form patterns. It has been shown that virus levels in chlorotic tissue are high, while they are low in healthy tissue. Additionally, the presence of siRNAs is confined to the chlorotic spots and the boundaries between healthy and infected tissue. These results strongly indicate that the interaction between virus growth and RNA silencing plays a role in the formation of infection patterns on leaves. However, how RNA silencing leads to the intricate patterns is not known. Results Here we elucidate the mechanisms leading to infection patterns and the conditions which lead to the various patterns observed. We present a modeling approach in which we combine intra- and inter-cellular dynamics of RNA silencing and viral growth. We observe that, due to the spread of viruses and the RNA silencing response, parts of the tissue become infected while other parts remain healthy. As is observed in experiments high virus levels coincide with high levels of siRNAs, and siRNAs are also present in the boundaries between infected and healthy tissue. We study how single- and double-stranded cleavage by Dicer and amplification by RNA-dependent RNA polymerase can affect the patterns formed. Conclusion This work shows that RNA silencing and virus growth within a cell, and the local spread of virions and siRNAs between cells can explain the heterogeneous spread of virus in leaf tissue, and therewith the observed infection patterns in plants.

  18. Obstructed pancreaticojejunostomy partly explains exocrine insufficiency after pancreatic head resection.

    Science.gov (United States)

    Nordback, Isto; Parviainen, Mickael; Piironen, Anneli; Räty, Sari; Sand, Juhani

    2007-02-01

    The majority of patients with long-term survival after pancreatic head resection suffer from pancreatic exocrine insufficiency. The objective of this study was to investigate whether this is due to glandular malfunction or obstructed pancreaticojejunal anastomosis. Twenty-six patients (10 M, 16 F, mean age 61 years, range 34-81 years) were re-examined a median of 52 months (range 3-76 months) after pancreatic head resection and end-to-end invaginated pancreaticojejunostomy. Pancreatic exocrine function was measured by fecal elastase-1 assay. The size of the pancreatic remnant, glandular secretion and the flow through the anastomosis were analyzed with secretin-stimulated dynamic magnetic resonance pancreatography (D-MRP). All patients had pancreatic exocrine insufficiency, 24 (92%) of them having severe insufficiency. Eighteen patients (69%) reported moderate to severe diarrhea. Lowest fecal elastase-1 concentrations were associated with the initial diagnosis of chronic pancreatitis or ductal adenocarcinoma, suggesting preoperative primary or secondary chronic pancreatitis as important determinants. The size of the remnant gland did not correlate with the fecal elastase-1 concentrations. D-MRP failed in three patients. Severe glandular malfunctions were found in 7 (30%) of the 23 successful D-MRP examinations. The anastomosis was totally obstructed in 5 patients (22%) or partially obstructed in 6 (26%) but remained perfectly open in 5 patients (22%). The five patients with perfect anastomoses had the highest measured median fecal elastase-1 activity. Although late diarrhea and pancreatic exocrine insufficiency may be partly induced already by the disease treated with resection, at least half may be explained by obstructed anastomosis. To obtain better late functional results, improvements may be required in the surgical techniques.

  19. Can physics help to explain embryonic development? An overview.

    Science.gov (United States)

    Fleury, V

    2013-10-01

    Recent technical advances including digital imaging and particle image velocimetry can be used to extract the full range of embryonic movements that constitute the instantaneous 'morphogenetic fields' of a developing animal. The final shape of the animal results from the sum over time (integral) of the movements that make up the velocity fields of all the tissue constituents. In vivo microscopy can be used to capture the details of vertebrate development at the earliest embryonic stages. The movements thus observed can be quantitatively compared to physical models that provide velocity fields based on simple hypotheses about the nature of living matter (a visco-elastic gel). This approach has cast new light on the interpretation of embryonic movement, folding, and organisation. It has established that several major discontinuities in development are simple physical changes in boundary conditions. In other words, with no change in biology, the physical consequences of collisions between folds largely explain the morphogenesis of the major structures (such as the head). Other discontinuities result from changes in physical conditions, such as bifurcations (changes in physical behaviour beyond specific yield points). For instance, beyond a certain level of stress, a tissue folds, without any new gene being involved. An understanding of the physical features of movement provides insights into the levers that drive evolution; the origin of animals is seen more clearly when viewed under the light of the fundamental physical laws (Newton's principle, action-reaction law, changes in symmetry breaking scale). This article describes the genesis of a vertebrate embryo from the shapeless stage (round mass of tissue) to the development of a small, elongated, bilaterally symmetric structure containing vertebral precursors, hip and shoulder enlarges, and a head. Copyright © 2013. Published by Elsevier Masson SAS.

  20. Methods to explain emission trends. From reference to realization

    International Nuclear Information System (INIS)

    Gijsen, A.; Oude Lohuis, J.

    2003-01-01

    Several methods are available to assess and determine the effects of policy measures. In this article methods to determine the effects of social and political developments on the emission of CO2 from the production of electricity in the Netherlands are discussed [nl

  1. An Integrated Model to Explain How Corporate Social Responsibility Affects Corporate Financial Performance

    Directory of Open Access Journals (Sweden)

    Chin-Shien Lin

    2015-06-01

    Full Text Available The effect of corporate social responsibility (CSR on financial performance has important implications for enterprises, communities, and countries, and the significance of this issue cannot be ignored. Therefore, this paper proposes an integrated model to explain the influence of CSR on financial performance with intellectual capital as a mediator and industry type as a moderator. Empirical results indicate that intellectual capital mediates the relationship between CSR and financial performance, and industry type moderates the direct influence of CSR on financial performance. Such results have critical implications for both academia and practice.

  2. Governance and performance: the performance of Dutch hospitals explained by governance characteristics.

    Science.gov (United States)

    Blank, Jos L T; van Hulst, Bart Laurents

    2011-10-01

    This paper describes the efficiency of Dutch hospitals using the Data Envelopment Analysis (DEA) method with bootstrapping. In particular, the analysis focuses on accounting for cost inefficiency measures on the part of hospital corporate governance. We use bootstrap techniques, as introduced by Simar and Wilson (J. Econom. 136(1):31-64, 2007), in order to obtain more efficient estimates of the effects of governance on the efficiency. The results show that part of the cost efficiency can be explained with governance. In particular we find that a higher remuneration of the board as well as a higher remuneration of the supervisory board does not implicate better performance.

  3. Snacking now or later? Individual differences in following intentions or habits explained by time perspective.

    Science.gov (United States)

    Onwezen, M C; Van 't Riet, J; Dagevos, H; Sijtsema, S J; Snoek, H M

    2016-12-01

    Even when individuals are aware of long-term health effects of their diet, and form healthy intentions, they often engage in relatively unhealthy snacking habits. Some individuals fall back on unhealthy habits more easily than others. We aim to explore whether time perspective can explain why some individuals are more prone to rely on habits and others on intentions. Study 1 (N = 1503) provides a first exploration of the role of time perspective by exploring individual differences in perception of long-term and short-term consequences. In accordance with our hypotheses, Study 1 shows that habits are associated with short-term consequences and intentions with long-term consequences. Study 2 (N = 1497) shows that the effects of habits on snacking behaviour are strengthened by a present time perspective, whereas the effects of intentions on snacking behaviour are strengthened by a future time perspective. These findings imply that there is a fundamental difference in the guiding function of intentions and habits which might explain individual differences in following intentions versus habits. Individuals with a long-term perspective are more inclined to follow intentions and individuals with a short-term perspective are more inclined to follow habits. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Multi-step inhibition explains HIV-1 protease inhibitor pharmacodynamics and resistance

    Science.gov (United States)

    Rabi, S. Alireza; Laird, Gregory M.; Durand, Christine M.; Laskey, Sarah; Shan, Liang; Bailey, Justin R.; Chioma, Stanley; Moore, Richard D.; Siliciano, Robert F.

    2013-01-01

    HIV-1 protease inhibitors (PIs) are among the most effective antiretroviral drugs. They are characterized by highly cooperative dose-response curves that are not explained by current pharmacodynamic theory. An unresolved problem affecting the clinical use of PIs is that patients who fail PI-containing regimens often have virus that lacks protease mutations, in apparent violation of fundamental evolutionary theory. Here, we show that these unresolved issues can be explained through analysis of the effects of PIs on distinct steps in the viral life cycle. We found that PIs do not affect virion release from infected cells but block entry, reverse transcription, and post–reverse transcription steps. The overall dose-response curves could be reconstructed by combining the curves for each step using the Bliss independence principle, showing that independent inhibition of multiple distinct steps in the life cycle generates the highly cooperative dose-response curves that make these drugs uniquely effective. Approximately half of the inhibitory potential of PIs is manifest at the entry step, likely reflecting interactions between the uncleaved Gag and the cytoplasmic tail (CT) of the Env protein. Sequence changes in the CT alone, which are ignored in current clinical tests for PI resistance, conferred PI resistance, providing an explanation for PI failure without resistance. PMID:23979165

  5. Is Titan's shape explained by its meteorology and carbon cycle?

    Science.gov (United States)

    Choukroun, M.; Sotin, C.

    2012-04-01

    Titan, Saturn's largest satellite, is unique in the Solar System: it is the only satellite bearing a dense atmosphere and it is the only place besides Earth with stable liquid bodies at its surface. In addition complex organics are produced in its atmosphere by the photolysis of methane, the second most abundant atmospheric molecule that irreversibly produces ethane and other more complex carbon bearing molecules. The Cassini/Huygens mission has revealed that the difference between its equatorial and polar radii is several hundred meters larger than that expected from its spin rate, and that it is in hydrostatic equilibrium. Global circulation models predict a large meridional circulation with upwelling at the summer hemisphere and downwelling at the winter pole where ethane can condense and fall at the surface. Lakes and Mare have been observed at the poles only (Stofan et al., Nature, 2007). Ethane has been spectroscopically identified in one of the lakes (Brown et al., Nature, 2008). The present study investigates the subsidence associated with ethane rain at the poles. As suggested by laboratory experiments, ethane flows very easily in a porous crust made of either pure water ice or methane clathrates. Loading of the lithosphere by liquid hydrocarbons induces a tendency of the polar terrains to subside relative to the lower latitudes terrains. In addition, laboratory experiments suggest that ethane substitutes to methane in a methane clathrate crust. The present study estimates the kinetics of this transformation. It suggests that such a transformation would occur on timescales much smaller than geological timescales. To explain a value of 270 m of the subsidence as determined by the radar instrument onboard the Cassini spacecraft (Zebker et al., Science, 2009), our study predicts that the percolation of ethane liquid in the polar crust should have operated during the last 300 - 1,200 Myr. This number is in agreement with the isotopic age of the atmospheric

  6. Force loading explains spatial sensing of ligands by cells

    Science.gov (United States)

    Oria, Roger; Wiegand, Tina; Escribano, Jorge; Elosegui-Artola, Alberto; Uriarte, Juan Jose; Moreno-Pulido, Cristian; Platzman, Ilia; Delcanale, Pietro; Albertazzi, Lorenzo; Navajas, Daniel; Trepat, Xavier; García-Aznar, José Manuel; Cavalcanti-Adam, Elisabetta Ada; Roca-Cusachs, Pere

    2017-12-01

    Cells can sense the density and distribution of extracellular matrix (ECM) molecules by means of individual integrin proteins and larger, integrin-containing adhesion complexes within the cell membrane. This spatial sensing drives cellular activity in a variety of normal and pathological contexts. Previous studies of cells on rigid glass surfaces have shown that spatial sensing of ECM ligands takes place at the nanometre scale, with integrin clustering and subsequent formation of focal adhesions impaired when single integrin-ligand bonds are separated by more than a few tens of nanometres. It has thus been suggested that a crosslinking ‘adaptor’ protein of this size might connect integrins to the actin cytoskeleton, acting as a molecular ruler that senses ligand spacing directly. Here, we develop gels whose rigidity and nanometre-scale distribution of ECM ligands can be controlled and altered. We find that increasing the spacing between ligands promotes the growth of focal adhesions on low-rigidity substrates, but leads to adhesion collapse on more-rigid substrates. Furthermore, disordering the ligand distribution drastically increases adhesion growth, but reduces the rigidity threshold for adhesion collapse. The growth and collapse of focal adhesions are mirrored by, respectively, the nuclear or cytosolic localization of the transcriptional regulator protein YAP. We explain these findings not through direct sensing of ligand spacing, but by using an expanded computational molecular-clutch model, in which individual integrin-ECM bonds—the molecular clutches—respond to force loading by recruiting extra integrins, up to a maximum value. This generates more clutches, redistributing the overall force among them, and reducing the force loading per clutch. At high rigidity and high ligand spacing, maximum recruitment is reached, preventing further force redistribution and leading to adhesion collapse. Measurements of cellular traction forces and actin flow speeds

  7. Wind turbine rotor aerodynamics : The IEA MEXICO rotor explained

    NARCIS (Netherlands)

    Zhang, Y.

    2017-01-01

    Wind turbines are operating under very complex and uncontrolled environmental conditions, including atmospheric turbulence, atmospheric boundary layer effects, directional and spatial variations in wind shear, etc. Over the past decades, the size of a commercial wind turbine has increased

  8. Explaining purchases of organic meat by Dutch consumers

    NARCIS (Netherlands)

    Verhoef, PC

    2005-01-01

    This study investigates the impact of economic and marketing variables ( quality, price, and distribution), emotions ( fear, empathy, and guilt), social norms, and environment-related variables ( environmental concern, green behaviour, and perceived consumer effectiveness) on Dutch consumers'

  9. Explaining attitudes about homosexuality in Confucian and non-Confucian nations: is there a 'cultural' influence?

    Science.gov (United States)

    Adamczyk, Amy; Cheng, Yen-hsin Alice

    2015-05-01

    The majority of research on attitudes about homosexuality has concentrated on the global North and on Christian and Muslim majority nations. Little research attention has been given to the factors that shape tolerance in societies with a Confucian heritage. Residents of Confucian counties are less tolerant than Europeans and Americans. One reason given for this difference is the emphasis on Confucian values in many Asian societies. Using data from the World Values Survey, we examine whether values that could be described as Confucian influence attitudes in Confucian and non-Confucian nations. We find a unique Confucian cultural effect, which can partially be explained with concerns about keeping the family intact. Conversely, in Confucian societies values related to obedience, conformity, and filial piety are unrelated to attitudes. There is also a small Buddhist contextual effect, resulting in more tolerant attitudes, and the Confucian influence cannot be reduced to an Asian regional effect. Published by Elsevier Inc.

  10. The mystery of Japan's missing centenarians explained

    Directory of Open Access Journals (Sweden)

    Yasuhiko Saito

    2012-03-01

    Full Text Available This report elucidates the issue of Japan's missing centenarians, which was uncovered in 2010. We provide the latest figures from verification efforts, discuss sources of centenarian information in Japan, examine possible causes, and evaluate the effect of the missing centenarians on official statistics. In Japan 234,354 people registered before 1910 remained on the family registers in 2010, without being crossed out. They would have been 100 years old at least and represent 0.5Š of the births recorded between 1872 and 1910. The impact of this group on life expectancy statistics, however, is effectively nil.

  11. Maternal distress explains the relationship of young African American mothers' violence exposure with their preschoolers' behavior.

    Science.gov (United States)

    Mitchell, Stephanie J; Lewin, Amy; Rasmussen, Andrew; Horn, Ivor B; Joseph, Jill G

    2011-02-01

    Adolescent mothers and their children are particularly susceptible to witnessing or directly experiencing violence. Such violence exposure predicts maternal distress, parenting, and child behavior problems. The current study examined how mothers' depressive symptoms, aggression, harsh disciplinary practices, and home environment independently explain the association between mothers' violence exposure and children's externalizing and internalizing behavior, controlling for their children's violence exposure. Data were collected from 230 African American mothers living in Washington, DC who gave birth as adolescents and whose children were 3 to 5 years old. Path analysis revealed that the effect of mothers' experienced violence on children's externalizing and internalizing behavior was mediated by mothers' depressive symptoms and aggression. However, neither harsh discipline nor stimulation in the home environment acted as significant mediators, and there were no direct or indirect effects of mothers' witnessed violence on child behavior. This study builds on previous work by identifying an association between maternal violence exposure and children's behavior, independent of children's own violence exposure that is explained by mothers' increased distress but not their parenting. These findings suggest that a potential means of preventing behavior problems in minority children born to adolescent mothers is to identify mothers who have been directly exposed to violence and treat their depressive symptoms and aggressive behaviors.

  12. Application of a social cognitive model in explaining physical activity in Iranian female adolescents.

    Science.gov (United States)

    Taymoori, P; Rhodes, R E; Berry, T R

    2010-04-01

    Adolescent Iranian girls are at high risk for physical inactivity due to cultural barriers such as restrictions regarding exercising in public and research is needed to explore ethnic and gender-related factors associated with physical activity (PA) participation. Using social cognitive theory as the guiding model, the purpose of this study was to test the fit and strength of barriers self-efficacy, outcome expectations, self-regulation and social support in explaining PA in female Iranian adolescents (n = 558). Using path analysis, social support was modeled as an antecedent of self-efficacy and outcome expectations, while self-efficacy was modeled as an antecedent of outcome expectations, self-regulatory planning and PA. Outcome expectations and self-regulatory planning were subsequently modeled as additional antecedents of PA. The model explained 52% of the variance in PA. The two significant (P < 0.05) direct effects were from self-efficacy and outcome expectations. Social support from mothers, fathers and friends had significant indirect effects on PA through self-efficacy. These results will allow for future research and interventions not only for female Iranian adolescents but also for similar cultural and immigrant groups that have been neglected to date in the PA literature.

  13. Climate change but not unemployment explains the changing suicidality in Thessaloniki Greece (2000-2012).

    Science.gov (United States)

    Fountoulakis, Konstantinos N; Savopoulos, Christos; Zannis, Prodromos; Apostolopoulou, Martha; Fountoukidis, Ilias; Kakaletsis, Nikolaos; Kanellos, Ilias; Dimellis, Dimos; Hyphantis, Thomas; Tsikerdekis, Athanasios; Pompili, Maurizio; Hatzitolios, Apostolos I

    2016-03-15

    Recently there was a debate concerning the etiology behind attempts and completed suicides. The aim of the current study was to search for possible correlations between the rates of attempted and completed suicide and climate variables and regional unemployment per year in the county of Thessaloniki, Macedonia, northern Greece, for the years 2000-12. The regional rates of suicide and attempted suicide as well as regional unemployment were available from previous publications of the authors. The climate variables were calculated from the daily E-OBS gridded dataset which is based on observational data Only the male suicide rates correlate significantly with high mean annual temperature but not with unemployment. The multiple linear regression analysis results suggest that temperature is the only variable that determines male suicides and explains 51% of their variance. Unemployment fails to contribute significantly to the model. There seems to be a seasonal distribution for attempts with mean rates being higher for the period from May to October and the rates clearly correlate with temperature. The highest mean rates were observed during May and August and the lowest during December and February. Multiple linear regression analysis suggests that temperature also determines the female attempts rate although the explained variable is significant but very low (3-5%) Climate variables and specifically high temperature correlate both with suicide and attempted suicide rates but with a different way between males and females. The climate effect was stronger than the effect of unemployment. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Relation between rainfall intensity and savanna tree abundance explained by water use strategies.

    Science.gov (United States)

    Xu, Xiangtao; Medvigy, David; Rodriguez-Iturbe, Ignacio

    2015-10-20

    Tree abundance in tropical savannas exhibits large and unexplained spatial variability. Here, we propose that differentiated tree and grass water use strategies can explain the observed negative relation between maximum tree abundance and rainfall intensity (defined as the characteristic rainfall depth on rainy days), and we present a biophysical tree-grass competition model to test this idea. The model is founded on a premise that has been well established in empirical studies, namely, that the relative growth rate of grasses is much higher compared with trees in wet conditions but that grasses are more susceptible to water stress and lose biomass more quickly in dry conditions. The model is coupled with a stochastic rainfall generator and then calibrated and tested using field observations from several African savanna sites. We show that the observed negative relation between maximum tree abundance and rainfall intensity can be explained only when differentiated water use strategies are accounted for. Numerical experiments reveal that this effect is more significant than the effect of root niche separation. Our results emphasize the importance of vegetation physiology in determining the responses of tree abundance to climate variations in tropical savannas and suggest that projected increases in rainfall intensity may lead to an increase in grass in this biome.

  15. Can individual health differences be explained by workplace characteristics?--A multilevel analysis.

    Science.gov (United States)

    Marklund, Staffan; Bolin, Malin; von Essen, Jan

    2008-02-01

    Research on work-related health has mainly focused on individual factors. The present study expands the focus by exploring the role of organizational characteristics of workplaces for different individual health outcomes. The aim of the study was to look at differences in relative effect of workplace variations on five health outcomes, and to explain those differences in health outcomes by organizational characteristics. The sample encompassed 90 workplaces in Sweden and about 4300 individuals employed within these workplaces. Measurement of the workplace characteristics was carried out independently of the measurement of the individual's working conditions and health. Organizational data were collected by interviews with local managers at participating workplaces, and individual data were obtained by means of a survey of the employees. The results showed that a significant proportion of the variance in sickness absence, work ability, general health, and musculoskeletal disorders was attributed to the workplace. Of eight tested organizational characteristics, customer adaptation, lean production, and performance control could explain some of this workplace variance. The results also showed that only one organizational effect remained significant when controlled for the individual confounder of age and gender. High customer adaptation is associated with higher sickness absence. This association is not mediated via differences in mental and physical job strain.

  16. Relational Regulation Theory : A New Approach to Explain the Link Between Perceived Social Support and Mental Health

    NARCIS (Netherlands)

    Lakey, Brian; Orehek, Edward

    Perceived support is consistently linked to good mental health, which is typically explained as resulting from objectively supportive actions that buffer stress. Yet this explanation has difficulty accounting for the often-observed main effects between support and mental health. Relational

  17. Explaining participation differentials in Dutch higher education: The impact of subjective success probabilities on level choice and field choice

    NARCIS (Netherlands)

    Tolsma, J.; Need, A.; Jong, U. de

    2010-01-01

    In this article we examine whether subjective estimates of success probabilities explain the effect of social origin, sex, and ethnicity on students' choices between different school tracks in Dutch higher education. The educational options analysed differ in level (i.e. university versus

  18. Can Research Design Explain Variation in Head Start Research Results? A Meta-Analysis of Cognitive and Achievement Outcomes

    Science.gov (United States)

    Shager, Hilary M.; Schindler, Holly S.; Magnuson, Katherine A.; Duncan, Greg J.; Yoshikawa, Hirokazu; Hart, Cassandra M. D.

    2013-01-01

    This study explores the extent to which differences in research design explain variation in Head Start program impacts. We employ meta-analytic techniques to predict effect sizes for cognitive and achievement outcomes as a function of the type and rigor of research design, quality and type of outcome measure, activity level of control group, and…

  19. Explaining participation differentials in Dutch higher education : the impact of subjective success probabilities on level choice and field choice

    NARCIS (Netherlands)

    Tolsma, J.; Need, A.; Jong, U. de

    2010-01-01

    In this article we examine whether subjective estimates of success probabilities explain the effect of social origin, sex, and ethnicity on students’ choices between different school tracks in Dutch higher education. The educational options analysed differ in level (i.e. university versus

  20. Explaining the adjustment of adolescents with type 1 diabetes: Role of diabetes-specific and psychosocial factors

    NARCIS (Netherlands)

    Malik, J.A.; Koot, H.M.

    2009-01-01

    OBJECTIVE - The aim of this study was to explain adjustment (diabetes-related quality of life, general well-being, and psychopathology) in adolescents with type 1 diabetes by testing the direct, mediating, and moderating effects of diabetes-specific and psychosocial factors, using an adapted version

  1. Human resource practices and organisational performance: Can the HRM-performance linkage be explained by the cooperative behaviours of employees?

    NARCIS (Netherlands)

    Lambooij, Mattijs; Sanders, Karin; Koster, Ferry; Zwiers, Marieke

    2006-01-01

    This paper addresses the question as to whether the linkage between HRM and organisational performance can be explained by the effect of the internal and strategic fit of HRM on the cooperative behaviours of employees. We expect that the more HRM practices are aligned within themselves (internal

  2. Can sleep deprivation studies explain why human adults sleep?

    Science.gov (United States)

    Brown, Lee K

    2012-11-01

    This review will concentrate on the consequences of sleep deprivation in adult humans. These findings form a paradigm that serves to demonstrate many of the critical functions of the sleep states. The drive to obtain food, water, and sleep constitutes important vegetative appetites throughout the animal kingdom. Unlike nutrition and hydration, the reasons for sleep have largely remained speculative. When adult humans are nonspecifically sleep-deprived, systemic effects may include defects in cognition, vigilance, emotional stability, risk-taking, and, possibly, moral reasoning. Appetite (for foodstuffs) increases and glucose intolerance may ensue. Procedural, declarative, and emotional memory are affected. Widespread alterations of immune function and inflammatory regulators can be observed, and functional MRI reveals profound changes in regional cerebral activity related to attention and memory. Selective deprivation of rapid eye movement (REM) sleep, on the contrary, appears to be more activating and to have lesser effects on immunity and inflammation. The findings support a critical need for sleep due to the widespread effects on the adult human that result from nonselective sleep deprivation. The effects of selective REM deprivation appear to be different and possibly less profound, and the functions of this sleep state remain enigmatic.

  3. Can Institutions Explain Cross-Country Differences in Innovative Activity?

    DEFF Research Database (Denmark)

    Wang, Cong

    2013-01-01

    –2009, this paper has found a significant direct effect of institutions on R&D intensity. Countries with better institutions qualities as captured by the World Banks’ Worldwide Governance Indicators (WGI) tend to attract more scientists and engineers into the research field and to spend more on R&D as well...

  4. Maternal characteristics largely explain poor pregnancy outcome after hyperemesis gravidarum

    NARCIS (Netherlands)

    Roseboom, Tessa J.; Ravelli, Anita C. J.; van der Post, Joris A.; Painter, Rebecca C.

    2011-01-01

    Objective: To describe the characteristics of women who suffer from hyperemesis gravidarum, and explore the independent effect of hyperemesis gravidarum on pregnancy outcome. Study design: In The Netherlands Perinatal Registry, we used all data on singleton pregnancies of at least 24 weeks and 500 g

  5. Attempt to explain the uranium 238 resonance integral discrepancy

    International Nuclear Information System (INIS)

    Tellier, H.; Grandotto, M.

    1978-01-01

    For light water reactor physics, studies on uranium 238 resonance integral discrepancy were carried out. It was shown that using recently published resonance parameters and substituting a multilevel formalism to the usual Breit and Wigner formula reduced the well known discrepancy between two values of the uranium 238 effective resonance integral: the value calculated with the nuclear data and the one deduced from critical experiments. Since the cross section computed with these assumptions agrees quite well with the Oak Ridge transmission data, it was used to obtain the self-shielding effect and the capture rate in light water lattices. The multiplication factor calculated with this method is found very close to the experimental value. Preliminary results for a set of benchmarks relative to several types of thermal neutron reactors lead to very low discrepancies. The reactivity loss is only 130 x 10 -5 instead of 650 x 10 -5 in the case of the usual libraries and the single level formula

  6. An attempt to explain the uranium 238 resonance integral discrepancy

    International Nuclear Information System (INIS)

    Tellier, H.; Grandotto, M.

    1978-01-01

    Studies on uranium 238 resonance integral discrepancy were carried out for light water reactor physics. It was shown that using recently published resonance parameters and substituting a multilevel formalism to the usual Breit and Wigner formula reduced the well known discrepancy between two values of the uranium 238 effective resonance integral: the value calculated with the nuclear data and the one deduced from critical experiments. Since the cross section computed with these assumptions agrees quite well with the Oak-Ridge transmission data, it was used to obtain the self-shielding effect and the capture rate in light water lattices. The multiplication factor calculated with this method is found very close to the experimental value. Preliminary results for a set of benchmarks relative to several types of thermal neutron reactors lead to very low discrepancies. The reactivity loss is only 130 x 10 -5 instead of 650 x 10 -5 in the case of the usual libraries and the single level formula

  7. How older persons explain why they became victims of abuse

    DEFF Research Database (Denmark)

    Mysyuk, Yuliya; Westendorp, Rudi Gerardus Johannes; Lindenberg, Jolanda

    2016-01-01

    understand the perceptions of older victims as they are among the most important groups to handle and report abuse. DESIGN: a qualitative study on the perceptions and experiences of victims of elder abuse was conducted using in-depth semi-structured interviews. SETTING: abused individuals living...... independently, in residential care facilities and nursing homes. SUBJECTS: six males and 11 females aged 63-90 years. RESULTS: the main causes of abuse identified by older victims themselves were mutual dependency between victim and perpetrator, power and control imbalances, loneliness and a marginalised social...... position of older persons. Effects of abuse included negative feelings, physical and psychological distress, a change of personal norms and values, changed perspectives on money and low self-efficacy. These differential effects depended upon the types of abuse experienced and the relationship...

  8. Do organizational and political-legal arrangements explain financial wrongdoing?

    Science.gov (United States)

    Prechel, Harland; Zheng, Lu

    2016-12-01

    The 2008 financial crisis was a systemic problem with deep-rooted structural causes that created opportunities to engage in financial malfeasance, a form of corporate wrongdoing. However, few quantitative studies exist on the effects of organizational and political-legal arrangements on financial malfeasance. In this paper, we examine the effects of organizational and political-legal arrangements that emerged in the 1990s in the FIRE sector (i.e., financial, insurance, and real estate) on financial malfeasance. Our historical contextualization demonstrates how changes in the political-legal arrangements facilitate the emergence of new corporate structures and opportunities for financial malfeasance. Our longitudinal quantitative analysis demonstrates that US FIRE sector corporations with a more complex organizational structure, larger size, lower dividend payment, and higher executive compensation are more prone to commit financial malfeasance. © London School of Economics and Political Science 2016.

  9. Explaining Russian manufacturing exports: Firm characteristics and external conditions

    OpenAIRE

    De Rosa, Donato

    2006-01-01

    This paper examines the exporting behaviour of Russian manufacturers by considering the effects of firm characteristics and external conditions. Two measures of export behaviour are considered: the decision to export and the share of exports to developed markets. I find that specific exporting experience is the main determinant of both export status and destination. Contrary to studies for other countries, firm features, with the exception of firm size, are irrelevant for export status, while...

  10. Could gender wage discrimination explain regional differences in productivity?

    OpenAIRE

    Yolanda Pena-Boquete; Melchor Fernandez

    2011-01-01

    Human capital and productive structure could account for an important part of the differences in productivity between Spanish regions; nevertheless we consider that gender wage discrimination could also have effects on it. The existence of a degree of discrimination means that there is a wage differential in which employer prefer to hire less productive workers instead of discriminated workers. Thus, the cost of producing a unit of product would be higher than the cost of producing without di...

  11. Explaining citizens’ perceptions of international climate-policy relevance

    International Nuclear Information System (INIS)

    Schleich, Joachim; Faure, Corinne

    2017-01-01

    This paper empirically analyses the antecedents of citizens’ perceptions of the relevance of international climate policy. Its use of representative surveys in the USA, China and Germany controls for different environmental attitudes and socio-economic factors between countries. The findings of the micro-econometric analysis suggest that the perceived relevance of international climate policy is positively affected by its perceived effectiveness, approval of the key topics discussed at international climate conferences, and environmental attitudes, but is not affected by perceived procedural justice. A higher level of perceived trust in international climate policy was positively related to perceived relevance in the USA and in China, but not in Germany. Citizens who felt that they were well informed and that their position was represented at climate summits were more likely to perceive international climate policy as relevant in China in particular. Generally, the results show only weak evidence of socio-demographic effects. - Highlights: • Perceptions of climate-policy relevance increase with perceptions of effectiveness. • In China and the USA, trust increases perceptions of climate-policy relevance. • Environmental attitudes are related to perceptions of climate-policy relevance. • In China, well-informed citizens perceive climate policy as more relevant. • Socio-demographics only weakly affect perceptions of climate-policy relevance.

  12. Explaining the Relationship between Employment and Juvenile Delinquency*

    Science.gov (United States)

    Staff, Jeremy; Osgood, D. Wayne; Schulenberg, John E.; Bachman, Jerald G.; Messersmith, Emily E.

    2011-01-01

    Most criminological theories predict an inverse relationship between employment and crime, but teenagers' involvement in paid work during the school year is positively correlated with delinquency and substance use. Whether the work-delinquency association is causal or spurious has long been debated. This study estimates the effect of paid work on juvenile delinquency using longitudinal data from the national Monitoring the Future project. We address issues of spuriousness by using a two-level hierarchical model to estimate the relationships of within-individual changes in juvenile delinquency and substance use to those in paid work and other explanatory variables. We also disentangle effects of actual employment from preferences for employment to provide insight about the likely role of time-varying selection factors tied to employment, delinquency, school engagement, and leisure activities. Whereas causal effects of employment would produce differences based on whether and how many hours respondents worked, we found significantly higher rates of crime and substance use among non-employed youth who preferred intensive versus moderate work. Our findings suggest the relationship between high-intensity work and delinquency results from preexisting factors that lead youth to desire varying levels of employment. PMID:21442045

  13. Can Professional Environments in Schools Promote Teacher Development? Explaining Heterogeneity in Returns to Teaching Experience

    Science.gov (United States)

    Kraft, Matthew A.; Papay, John P.

    2014-01-01

    Although wide variation in teacher effectiveness is well established, much less is known about differences in teacher improvement over time. We document that average returns to teaching experience mask large variation across individual teachers and across groups of teachers working in different schools. We examine the role of school context in explaining these differences using a measure of the professional environment constructed from teachers responses to state-wide surveys. Our analyses show that teachers working in more supportive professional environments improve their effectiveness more over time than teachers working in less supportive contexts. On average, teachers working in schools at the 75th percentile of professional environment ratings improved 38% more than teachers in schools at the 25th percentile after 10 years. PMID:25866426

  14. Can Professional Environments in Schools Promote Teacher Development? Explaining Heterogeneity in Returns to Teaching Experience.

    Science.gov (United States)

    Kraft, Matthew A; Papay, John P

    2014-12-01

    Although wide variation in teacher effectiveness is well established, much less is known about differences in teacher improvement over time. We document that average returns to teaching experience mask large variation across individual teachers and across groups of teachers working in different schools. We examine the role of school context in explaining these differences using a measure of the professional environment constructed from teachers responses to state-wide surveys. Our analyses show that teachers working in more supportive professional environments improve their effectiveness more over time than teachers working in less supportive contexts. On average, teachers working in schools at the 75th percentile of professional environment ratings improved 38% more than teachers in schools at the 25th percentile after 10 years.

  15. Documenting and explaining the common AAB pattern in music and humor: establishing and breaking expectations.

    Science.gov (United States)

    Rozin, Paul; Rozin, Alexander; Appel, Brian; Wachtel, Charles

    2006-08-01

    The AAB pattern consists of two similar events followed by a third dissimilar event. The prevalence of this pattern in the aesthetic domain may be explained as violation of expectation: A minimum of two iterations is required to establish a repetitive pattern; once established, it is most efficient to promptly violate the expected continuance of the pattern to produce the maximal aesthetic effect. We demonstrate the prevalence of this pattern (in comparison to AB or AAAB) in a representative sample of a variety of musical genres and in a representative sample of repetitive genre of jokes. We also provide experimental evidence that the AAB pattern in jokes is maximally effective in producing a humor response in participants. (c) 2006 APA, all rights reserved

  16. What explains the American disadvantage in health compared with the English? The case of diabetes.

    Science.gov (United States)

    Banks, James; Kumari, Meena; Smith, James P; Zaninotto, Paola

    2012-03-01

    Middle-aged and older American men and women have almost twice the rate of diabetes of men and women in England. This differential was not explained by conventional risk factors including age, smoking, social position and body mass index (BMI). This study used large and representative samples of non-minority adults aged 52-85 years taken from the 1999-2006 American National Health and Nutrition Examination Survey (NHANES) and the 2004 English Longitudinal Study of Aging. The surveys contain self-reported and objective biological disease markers of diabetes as well as indicators of major risk factors for diabetes including anthropometric measures of BMI, height and waist circumference. The older American population has much higher rates of diabetes than the English population-a differential not yet explained, but this population also has higher waist circumference at each level of BMI than does the equivalent group in England. By controlling for such waist circumference differences and allowing for different effects of waist on diabetes in each country, approximately three-quarters of the country differences for women and 38% among men can be explained. Higher rates of diabetes in the US old-age population than in England were largely accounted for by raised waist circumference and not BMI differences, especially among women. In addition, elevated diabetes risk associated with higher waist circumference in the USA as opposed to England could arise as a result of a number of different mechanisms. Investigation of the relative importance of such mechanisms is an important topic for further study.

  17. Linear programming model can explain respiration of fermentation products.

    Directory of Open Access Journals (Sweden)

    Philip Möller

    Full Text Available Many differentiated cells rely primarily on mitochondrial oxidative phosphorylation for generating energy in the form of ATP needed for cellular metabolism. In contrast most tumor cells instead rely on aerobic glycolysis leading to lactate to about the same extent as on respiration. Warburg found that cancer cells to support oxidative phosphorylation, tend to ferment glucose or other energy source into lactate even in the presence of sufficient oxygen, which is an inefficient way to generate ATP. This effect also occurs in striated muscle cells, activated lymphocytes and microglia, endothelial cells and several mammalian cell types, a phenomenon termed the "Warburg effect". The effect is paradoxical at first glance because the ATP production rate of aerobic glycolysis is much slower than that of respiration and the energy demands are better to be met by pure oxidative phosphorylation. We tackle this question by building a minimal model including three combined reactions. The new aspect in extension to earlier models is that we take into account the possible uptake and oxidation of the fermentation products. We examine the case where the cell can allocate protein on several enzymes in a varying distribution and model this by a linear programming problem in which the objective is to maximize the ATP production rate under different combinations of constraints on enzymes. Depending on the cost of reactions and limitation of the substrates, this leads to pure respiration, pure fermentation, and a mixture of respiration and fermentation. The model predicts that fermentation products are only oxidized when glucose is scarce or its uptake is severely limited.

  18. An approach to explainable deep learning using fuzzy inference

    Science.gov (United States)

    Bonanno, David; Nock, Kristen; Smith, Leslie; Elmore, Paul; Petry, Fred

    2017-05-01

    Deep Learning has proven to be an effective method for making highly accurate predictions from complex data sources. Convolutional neural networks continue to dominate image classification problems and recursive neural networks have proven their utility in caption generation and language translations. While these approaches are powerful, they do not offer explanation for how the output is generated. Without understanding how deep learning arrives at a solution there is no guarantee that these networks will transition from controlled laboratory environments to fieldable systems. This paper presents an approach for incorporating such rule based methodology into neural networks by embedding fuzzy inference systems into deep learning networks.

  19. Can theories of animal discrimination explain perceptual learning in humans?

    Science.gov (United States)

    Mitchell, Chris; Hall, Geoffrey

    2014-01-01

    We present a review of recent studies of perceptual learning conducted with nonhuman animals. The focus of this research has been to elucidate the mechanisms by which mere exposure to a pair of similar stimuli can increase the ease with which those stimuli are discriminated. These studies establish an important role for 2 mechanisms, one involving inhibitory associations between the unique features of the stimuli, the other involving a long-term habituation process that enhances the relative salience of these features. We then examine recent work investigating equivalent perceptual learning procedures with human participants. Our aim is to determine the extent to which the phenomena exhibited by people are susceptible to explanation in terms of the mechanisms revealed by the animal studies. Although we find no evidence that associative inhibition contributes to the perceptual learning effect in humans, initial detection of unique features (those that allow discrimination between 2 similar stimuli) appears to depend on an habituation process. Once the unique features have been detected, a tendency to attend to those features and to learn about their properties enhances subsequent discrimination. We conclude that the effects obtained with humans engage mechanisms additional to those seen in animals but argue that, for the most part, these have their basis in learning processes that are common to animals and people. In a final section, we discuss some implications of this analysis of perceptual learning for other aspects of experimental psychology and consider some potential applications. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  20. Behavioural Contagion Explains Group Cohesion in a Social Crustacean.

    Science.gov (United States)

    Broly, Pierre; Deneubourg, Jean-Louis

    2015-06-01

    In gregarious species, social interactions maintain group cohesion and the associated adaptive values of group living. The understanding of mechanisms leading to group cohesion is essential for understanding the collective dynamics of groups and the spatio-temporal distribution of organisms in environment. In this view, social aggregation in terrestrial isopods represents an interesting model due to its recurrence both in the field and in the laboratory. In this study, and under a perturbation context, we experimentally tested the stability of groups of woodlice according to group size and time spent in group. Our results indicate that the response to the disturbance of groups decreases with increases in these two variables. Models neglecting social effects cannot reproduce experimental data, attesting that cohesion of aggregation in terrestrial isopods is partly governed by a social effect. In particular, models involving calmed and excited individuals and a social transition between these two behavioural states more accurately reproduced our experimental data. Therefore, we concluded that group cohesion (and collective response to stimulus) in terrestrial isopods is governed by a transitory resting state under the influence of density of conspecifics and time spent in group. Lastly, we discuss the nature of direct or indirect interactions possibly implicated.