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-metrizable spaces and related matters
Zhiming Luo
International Journal of Mathematics and Mathematical Sciences , 2005, DOI: 10.1155/ijmms.2005.2523
Abstract: We give a mapping theorem on sn-metrizable spaces, discuss relationships among spaces with point-countable sn-networks, spaces with uniform sn-networks, spaces with locally countable sn-networks, spaces with σ-locally countable sn-networks, and sn-metrizable spaces, and obtain some related results.
DSEs and pseudoscalar mesons: an aperc,u  [PDF]
A. Hoell,A. Krassnigg,C. D. Roberts
Physics , 2003,
Abstract: An hallmark of present-day Dyson-Schwinger equation applications in hadron physics is the existence of a systematic and symmetry preserving truncation scheme. This enables the proof of exact results; e.g., the leptonic decay constant of every pseudoscalar meson except the pion vanishes in the chiral limit. Calculations using the scheme's leading-order truncation are reliable in the vector and flavour nonsinglet pseudoscalar channels. In this rainbow-ladder truncation, an impulse approximation provides the consistent current for all six-point quark Schwinger functions. That is well illustrated via the anomalous process pi0 -> gamma gamma. Using two-, three- and four-point Schwinger functions calculated in rainbow-ladder truncation, the textbook value of the width is obtained algebraically and independent of model details if, and only if, the impulse approximation is used to describe the associated matrix element.
Precarious Matters (report)
Klaus Ruthenberg
Hyle : International Journal for Philosophy of Chemistry , 2007,
Abstract: report of Precarious Matters
Pion-to-photon transition distribution amplitudes and related form factors in the non-local chiral quark model  [cached]
Kotko Piotr
EPJ Web of Conferences , 2012, DOI: 10.1051/epjconf/20123708008
Abstract: Transition distribution amplitudes (TDAs) are non-perturbative quantities appearing in the description of certain exclusive processes, for instance hadron-anti-hadron annihilation HH → γ*γ or backward virtual Compton scattering. They are similar to generalized parton distributions (GPDs), except that the non-diagonality concerns not only the momenta, but also the physical states (they are defined in terms of hadron-photon matrix element of a non-local operator). For the case of hadronic states such as pions, there are two TDAs of interest: the vector and the axial one. They are straightforwardly related to the axial and vector form factors controlling weak pion decays π± → e±νγ. The value at zero momentum transfer of the vector form factor is fixed by the axial anomaly, while this is not the case for the axial one. Moreover, the vector form factor is related to the pion-photon transition form factor which was recently measured by Belle and BaBar giving contradictory results at high momentum transfers. We have studied pion-to-photon TDAs within the non-local chiral quark model using modified non-local currents satisfying Ward-Takahashi identities. We found that the value of the axial form factor at zero momentum transfer is shifted towards the experimental value due to the non-locality of the model (in the local quark models the values of both vector and axial form factors at zero momentum transfer are the same, what is not consistent with the data). We also calculate the pion-photon transition form factor and compare it with the data.
Sex Matters during Adolescence: Testosterone-Related Cortical Thickness Maturation Differs between Boys and Girls  [PDF]
Jennifer E. Bramen, Jennifer A. Hranilovich, Ronald E. Dahl, Jessie Chen, Carly Rosso, Erika E. Forbes, Ivo D. Dinov, Carol M. Worthman, Elizabeth R. Sowell
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0033850
Abstract: Age-related changes in cortical thickness have been observed during adolescence, including thinning in frontal and parietal cortices, and thickening in the lateral temporal lobes. Studies have shown sex differences in hormone-related brain maturation when boys and girls are age-matched, however, because girls mature 1–2 years earlier than boys, these sex differences could be confounded by pubertal maturation. To address puberty effects directly, this study assessed sex differences in testosterone-related cortical maturation by studying 85 boys and girls in a narrow age range and matched on sexual maturity. We expected that testosterone-by-sex interactions on cortical thickness would be observed in brain regions known from the animal literature to be high in androgen receptors. We found sex differences in associations between circulating testosterone and thickness in left inferior parietal lobule, middle temporal gyrus, calcarine sulcus, and right lingual gyrus, all regions known to be high in androgen receptors. Visual areas increased with testosterone in boys, but decreased in girls. All other regions were more impacted by testosterone levels in girls than boys. The regional pattern of sex-by-testosterone interactions may have implications for understanding sex differences in behavior and adolescent-onset neuropsychiatric disorders.
Out of control mortality matters: the effect of perceived uncontrollable mortality risk on a health-related decision  [PDF]
Gillian V. Pepper,Daniel Nettle
PeerJ , 2015, DOI: 10.7717/peerj.459
Abstract: Prior evidence from the public health literature suggests that both control beliefs and perceived threats to life are important for health behaviour. Our previously presented theoretical model generated the more specific hypothesis that uncontrollable, but not controllable, personal mortality risk should alter the payoff from investment in health protection behaviours. We carried out three experiments to test whether altering the perceived controllability of mortality risk would affect a health-related decision. Experiment 1 demonstrated that a mortality prime could be used to alter a health-related decision: the choice between a healthier food reward (fruit) and an unhealthy alternative (chocolate). Experiment 2 demonstrated that it is the controllability of the mortality risk being primed that generates the effect, rather than mortality risk per se. Experiment 3 showed that the effect could be seen in a surreptitious experiment that was not explicitly health related. Our results suggest that perceptions about the controllability of mortality risk may be an important factor in people’s health-related decisions. Thus, techniques for adjusting perceptions about mortality risk could be important tools for use in health interventions. More importantly, tackling those sources of mortality that people perceive to be uncontrollable could have a dual purpose: making neighbourhoods and workplaces safer would have the primary benefit of reducing uncontrollable mortality risk, which could lead to a secondary benefit from improved health behaviours.
Out of control mortality matters: the effect of perceived uncontrollable mortality risk on a health-related decision  [PDF]
Gillian V Pepper,Daniel Nettle
PeerJ , 2015, DOI: 10.7287/peerj.preprints.318v2
Abstract: Prior evidence from the public health literature suggests that both control beliefs and perceived threats to life are important for health behaviour. Our previously presented theoretical model generated the more specific hypothesis that uncontrollable, but not controllable, personal mortality risk should alter the payoff from investment in health protection behaviours. We carried out three experiments to test whether altering the perceived controllability of mortality risk would affect a health-related decision. Experiment 1 demonstrated that a mortality prime could be used to alter a health-related decision: the choice between a healthier food reward (fruit) and an unhealthy alternative (chocolate). Experiment 2 demonstrated that it is the controllability of the mortality risk being primed that generates the effect, rather than mortality risk per se. Experiment 3 showed that the effect could be seen in a surreptitious experiment that was not explicitly health related. Our results suggest that perceptions about the controllability of mortality risk may be an important factor in people’s health-related decisions. Thus, techniques for adjusting perceptions about mortality risk could be important tools for use in health interventions. More importantly, tackling those sources of mortality that people perceive to be uncontrollable could have a dual purpose: Making neighbourhoods and workplaces safer would have the primary benefit of reducing uncontrollable mortality risk, which could lead to a secondary benefit from improved health behaviours.
The Evolution of beliefs and opinions on matters related to marriage and sexual behaviour among French-speaking Catholic Quebecers and English-speaking Protestant Ontarians  [PDF]
Malherbe, Paskall,Miller, Caia,Laplante, Benoit
Canadian Studies in Population , 2006,
Abstract: English The authors argue that the important changes in behaviour related to family andsexual life that were seen in Quebec during the second half of the 20th centuryare a consequence of a major transformation of the foundation of the normativesystem shared by the members of Quebec's main socio-religious group, French speakingCatholics. Using data from Gallup polls, the authors compare theevolution of the opinions of French-speaking Quebec Catholics and English speakingOntario Protestants on matters related to sexual and family behaviourfrom the 1950s to the beginning of the 2000s. The general result is that theevolution of the differences between the two groups is compatible with thehypothesis. French Les auteurs proposent d’expliquer les importants changements qui se sontproduits, dans le Québec de la deuxième moitié du 20e siècle, dans lescomportements liés à la famille et à la vie sexuelle par la transformation dusystème normatif des membres de son principal groupe socio-religieux, lesfrancophones catholiques. à partir des données de sondages Gallup, ilscomparent l'évolution des opinions des francophones catholiques du Québec etdes anglophones protestants de l’Ontario sur des questions liées à la famille etau comportement sexuel et de famille des années 1950 à 2000. L’évolution desdifférences entre les deux groupes est compatible avec l’hypothèse.
Beyond the rainbow: effects from pion back-coupling
Fischer, Christian S.;Williams, Richard
High Energy Physics - Phenomenology , 2008, DOI: 10.1103/PhysRevD.78.074006
Abstract: We investigate hadronic unquenching effects in light quarks and mesons. To this end we take into account the back-coupling of the pion onto the quark propagator within the non-perturbative continuum framework of Schwinger-Dyson equations (SDE) and Bethe-Salpeter equations (BSE). We improve on a previous approach by explicitly solving both the coupled system of DSEs and BSEs in the complex plane and the normalisation problem for Bethe-Salpeter kernels depending on the total momentum of the meson. As a result of our study we find considerable unquenching effects in the spectrum of light pseudoscalar, vector and axial-vector mesons.
Beyond the rainbow: effects from pion back-coupling  [PDF]
Christian S. Fischer,Richard Williams
Physics , 2008, DOI: 10.1103/PhysRevD.78.074006
Abstract: We investigate hadronic unquenching effects in light quarks and mesons. To this end we take into account the back-coupling of the pion onto the quark propagator within the non-perturbative continuum framework of Schwinger-Dyson equations (SDE) and Bethe-Salpeter equations (BSE). We improve on a previous approach by explicitly solving both the coupled system of DSEs and BSEs in the complex plane and the normalisation problem for Bethe-Salpeter kernels depending on the total momentum of the meson. As a result of our study we find considerable unquenching effects in the spectrum of light pseudoscalar, vector and axial-vector mesons.
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