Pion Compton scattering and bremsstrahlung

The pion-polarizability functions are structure functions of pion-Compton scattering. They can be assessed in high-energy pion-nucleus bremsstrahlung reactions, $\pi^- +A\to\pi^- +\gamma +A$. We present numerical expectations for pion-nucleus bremsstrahlung cross sections in the Coulomb region, i.e. the small-angle region where the nuclear scattering is dominated by the Coulomb interaction. We investigate the prospects of measuring the polarizability functions for pion-Compton c.m. energies from threshold up to 1 GeV. A meson-exchange model is used for the pion-Compton amplitude.Comment: 20 pages, 11 figure

Hard pion bremsstrahlung in the Coulomb region

Hard high-energy pion-nucleus bremsstrahlung, $\pi^- +A\to\pi^- +\gamma +A$, is studied in the Coulomb region, i.e. the small-angle region where the nuclear scattering is dominated by the Coulomb interaction. Special attention is focussed on the possibility of measuring the pion polarizability in such reactions. We study the sensitivity to the structure of the underlying the pion-Compton amplitude through a model with $\sigma$, $\rho$, and a_1 exchanges. It is found that the effective energy in the virtual pion-Compton scattering is often so large that the threshold approximation does not apply.Comment: 18 pages, 5 figure

Coulomb-nuclear interference in pion-nucleus bremsstrahlung

Pion-nucleus bremsstrahlung offers a possibility of measuring the structure functions of pion-Compton scattering from a study of the small-momentum-transfer region where the bremsstrahlung reaction is dominated by the single-photon-exchange mechanism. The corresponding cross-section distribution is characterized by a sharp peak at small momentum transfers. But there is also a hadronic contribution which is smooth and constitutes an undesired background. In this communication the modification of the single-photon exchange amplitude by multiple-Coulomb scattering is investigated as well as the Coulomb-nuclear interference term.Comment: 21 pages, 5 figures. Eqs.(51,52) corrected; some new figure

Modeling the burnout of solid polydisperse fuel under the conditions of external heat transfer

A self-similar burnout mode of solid polydisperse fuel is considered taking into consideration heat transfer between fuel particles, gases, and combustion chamber walls. A polydisperse composition of fuel is taken into account by introducing particle distribution functions by radiuses obtained for the kinetic and diffusion combustion modes. Equations for calculating the temperatures of particles and gases are presented, which are written for particles average with respect to their distribution functions by radiuses taking into account the fuel burnout ratio. The proposed equations take into consideration the influence of fuel composition, air excess factor, and gas recirculation ratio. Calculated graphs depicting the variation of particle and gas temperatures, and the fuel burnout ratio are presented for an anthracite-fired boiler. © 2013 Pleiades Publishing, Inc

Anisotropic photoconductivity in graphene

We investigate the photoconductivity of graphene within the relaxation time approximation. In presence of the inter-band transitions induced by the linearly polarized light the photoconductivity turns out to be highly anisotropic due to the pseudospin selection rule for Dirac-like carriers. The effect can be observed in clean undoped graphene samples and be utilized for light polarization detection.Comment: 4 pages, 2 figure

Frequency dependent conductivity of vortex cores in type II superconductors

This paper is relevant to the recent optical transmission experiments of Karrai et al. for vortices in high Tc superconductors. We begin with a substantial review and introduction. The microscopic response of vortices is calculated from the Bogoliubov-deGennes equation, including an equation of motion and conductivity. We find that the expected resonant dipole transtition is not present because of translation invariance. We consider the effect of pinning and show that in the presence of pinning one recovers the dipole resonance. Thus we conclude that pinning may play an important role in the experiment.Comment: 35 pages plus six pages of figures: not included but postscript files available upon request. Send requests and other comments to: [email protected]. Revte

When the sound becomes the goal. 4E cognition and teleomusicality in early infancy

In this paper we explore early musical behaviors through the lenses of the recently emerged "4E" approach to mind, which sees cognitive processes as Embodied, Embedded, Enacted, and Extended. In doing so, we draw from a range of interdisciplinary research, engaging in critical and constructive discussions with both new findings and existing positions. In particular, we refer to observational research by French pedagogue and psychologist François Delalande, who examined infants' first "sound discoveries" and individuated three different musical "conducts" inspired by the "phases of the game" originally postulated by Piaget. Elaborating on such ideas we introduce the notion of "teleomusicality," which describes the goal-directed behaviors infants adopt to explore and play with sounds. This is distinguished from the developmentally earlier "protomusicality," which is based on music-like utterances, movements, and emotionally relevant interactions (e.g., with primary caregivers) that do not entail a primary focus on sound itself. The development from protomusicality to teleomusicality is discussed in terms of an "attentive shift" that occurs between 6 and 10 months of age. This forms the basis of a conceptual framework for early musical development that emphasizes the emergence of exploratory, goal-directed (i.e., sound-oriented), and self-organized musical actions in infancy. In line with this, we provide a preliminary taxonomy of teleomusical processes discussing "Original Teleomusical Acts" (OTAs) and "Constituted Teleomusical Acts" (CTAs). We argue that while OTAs can be easily witnessed in infants' exploratory behaviors, CTAs involve the mastery of more specific and complex goal-directed chains of actions central to musical activity

Cutaneous manifestations of the disease reklingauzena : a literature review

Neurofibromatosis type 1 is one of the most common neurocutaneous diseases. Normally a dermatologist is the first specialist who may suspect the disease. Despite the fact that gene mutation in disease Reklingauzena has been identified in chromosome 17 in 1987, diagnosis is still based mainly on the identification of clinical symptoms. Among the diagnostic signs recommended by the International Committee of experts on neurofibromatosis, 3 criteria apply to skin manifestations. In addition to classic manifestations, the presence of other elements such as anemic nevus and juvenile xanthogranuloma can also have prognostic value. Neurofibromatosis is a Multisystem disease with a varied clinical picture, varying with age, which justifies the inclusion of follow-up not only of the doctor-dermatologist, but also related professionals.Нейрофиброматоз 1 типа – одно из наиболее распространенных нейрокожных заболеваний. Как правило, дерматовенеролог становится первым специалистом, который может заподозрить данное заболевание. Несмотря на то, что мутация гена при болезни Реклингаузена была выявлена в 17 хромосоме еще в 1987 году, диагностика заболевания до сих пор основывается главным образом на выявлении клинических симптомов. Среди диагностических признаков, рекомендованных Международным комитетом экспертов по нейрофиброматозу, 3 критерия относятся к кожным проявлениям. В дополнение к классическим признакам, наличие других элементов, таких как анемический невус и ювенильная ксантогранулема также могут иметь прогностическое значение. Нейрофиброматоз является мультисистемным заболеванием, с разнообразной клинической картиной, меняющейся с возрастом, что обосновывает включение в диспансерное наблюдения не только врача-дерматовенеролога, но и смежных специалистов

Cutaneous manifestations of the disease reklingauzena : a literature review

Neurofibromatosis type 1 is one of the most common neurocutaneous diseases. Normally a dermatologist is the first specialist who may suspect the disease. Despite the fact that gene mutation in disease Reklingauzena has been identified in chromosome 17 in 1987, diagnosis is still based mainly on the identification of clinical symptoms. Among the diagnostic signs recommended by the International Committee of experts on neurofibromatosis, 3 criteria apply to skin manifestations. In addition to classic manifestations, the presence of other elements such as anemic nevus and juvenile xanthogranuloma can also have prognostic value. Neurofibromatosis is a Multisystem disease with a varied clinical picture, varying with age, which justifies the inclusion of follow-up not only of the doctor-dermatologist, but also related professionals.Нейрофиброматоз 1 типа – одно из наиболее распространенных нейрокожных заболеваний. Как правило, дерматовенеролог становится первым специалистом, который может заподозрить данное заболевание. Несмотря на то, что мутация гена при болезни Реклингаузена была выявлена в 17 хромосоме еще в 1987 году, диагностика заболевания до сих пор основывается главным образом на выявлении клинических симптомов. Среди диагностических признаков, рекомендованных Международным комитетом экспертов по нейрофиброматозу, 3 критерия относятся к кожным проявлениям. В дополнение к классическим признакам, наличие других элементов, таких как анемический невус и ювенильная ксантогранулема также могут иметь прогностическое значение. Нейрофиброматоз является мультисистемным заболеванием, с разнообразной клинической картиной, меняющейся с возрастом, что обосновывает включение в диспансерное наблюдения не только врача-дерматовенеролога, но и смежных специалистов