3,078 research outputs found
Adolphe Nysenholc, Charles Chaplin ou la légende des images, Paris, Méridiens Kincksieck, 1987, 234 p.
Comments on the Relativity of Shape
In this talk I address three topics related to the shape of hadrons:
1. The Lorentz contraction of bound states. Few dedicated studies of this
exist - I describe a recent calculation for ordinary atoms (positronium).
2. Does the A-dependence of nuclear structure functions indicate a change of
proton shape in the nuclear environment? (My short answer is no.)
3. The size of Fock states contributing to processes involving large momentum
transfers. End-point configurations can be transversally extended and yet
sufficiently short-lived to contribute coherently to hard scattering.Comment: Talk at the Workshop on the Shape of Hadrons, 27-29 April 2006 in
Athens, Greece. 11 pages, 15 figure
Test of variational transition state theory against accurate quantal results for a reaction with very large reaction-path curvature and a low barrier
We present three sets of calculations for the thermal rate constants of the collinear reaction I+HI-->IH+I: accurate quantum mechanics, conventional transition state theory (TST), and variational transition state theory (VTST). This reaction differs from previous test cases in that it has very large reaction-path curvature but hardly any tunneling. TST overestimates the accurate results by factors of 2Ă10^10, 2Ă10^4, 57, and 19 at 40, 100, 300, and 1000 K, respectively. At these same four temperatures the ratios of the VTST results to the accurate quantal ones are 0.3, 0.8, 1.1, and 1.4, respectively. We conclude that the variational transition states are meaningful, even though they are computed from a reaction-path Hamiltonian with large curvature, which is the most questionable case
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Reply to: fMRI replicability depends upon sufficient individual-level data.
The phenotype of circulating follicular-helper T cells in patients with rheumatoid arthritis defines CD200 as a potential therapeutic target
Rheumatoid arthritis (RA) is a systemic autoimmune disease primarily affecting synovial joints in which the development of autoantibodies represents a failure of normal tolerance mechanisms, suggesting a role for follicular helper T cells (TFH) in the genesis of autoimmunity. To determine whether quantitative or qualitative abnormalities in the circulating TFH cell population exist, we analysed by flow cytometry the number and profile of these cells in 35 patients with RA and 15 matched controls. Results were correlated with patient characteristics, including the presence of autoantibodies, disease activity, and treatment with biologic agents. Circulating TFH cells from patients with RA show significantly increased expression of the immunoglobulin superfamily receptor CD200, with highest levels seen in seropositive patients (P=0.0045) and patients treated with anti-TNFα agents (P=0.0008). This occurs in the absence of any change in TFH numbers or overt bias towards Th1, Th2, or Th17 phenotypes. CD200 levels did not correlate with DAS28 scores (P=0.887). Although the number of circulating TFH
cells is not altered in the blood of patients with RA, the TFH
cells have a distinct phenotype. These differences associate TFH
cells with the pathogenesis of RA and support the relevance of the CD200/CD200R signalling pathway as a potential therapeutic target
The Role of Coaches, Institutions, and Clinicians in Addressing Athlete Mental Health
Mental health, defined by the World Health Organization as âa state of wellbeing in which every individual realizes his or her own potential, can cope with normal stresses of life, can work productively and fruitfully, and is able to make a contribution to her or his community,â is an important concern for athletes. In 2018, research findings showed that the prevalence of mental health symptoms and disorders among current elite athletes ranged from 19% for alcohol misuse to 34% for anxiety/depression, and from 16% for distress to 26% for anxiety/depression for former elite athletes.2 Research suggests that while athletes have overall better physical health than their non-athlete counterparts, they experience similar rates of mental health symptoms and disorders.https://digitalcommons.library.tru.ca/emergingdiscourses/1001/thumbnail.jp
Histoire littéraire/Histoire culturelle
Le rĂ©cent Que sais-je ? de Pascal Ory sur lâhistoire culturelle fait un incessant appel au dialogue entre les disciplines historiques. Mon intervention dans ce dialogue est celle dâun historien de la littĂ©rature, reprĂ©sentant (non autorisĂ©) dâune discipline qui se veut Ă la fois pleinement historique et pleinement littĂ©raire, donc pleinement culturelle. Avec ce paradoxe qui doit ĂȘtre dit dâemblĂ©e : Ă savoir que je ne suis pas historien patentĂ©, et que nombre de collĂšgues peuvent lĂ©gitimement ..
Salud Camarada ! Un reportage sur la guerre dâEspagne par Mathieu Corman
La guerre dâEspagne a Ă©tĂ© un Ă©vĂ©nement historique majeur. On y a vu, Ă juste titre, les prolĂ©gomĂšnes de la seconde guerre mondiale. Tous les grands acteurs de la politique europĂ©enne y ont participĂ© (les pays capitalistes-dĂ©mocratiques, les pays fascistes-nazis et les pays qui se rĂ©clamaient du socialisme). Les effets du conflit nâont pas Ă©tĂ© moins importants. Les dĂ©chirures de la sociĂ©tĂ© espagnole qui en ont rĂ©sultĂ© sâobservent encore de nos jours. Ă lâĂ©poque mĂȘme, par ailleurs, il sâest agi..
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