Electromagnetic Structure of the Pion

In this work, we analyze the electromagnetic structure of the pion. We calculate its electromagnetic radius and electromagnetic form factor in low and intermediate momentum range. Such observables are determined by means of a theoretical model that takes into account the constituent quark and antiquark of the pion within the formalism of light-front field theory. In particular, we consider a nonsymmetrical vertex in this model, with which we calculate the electromagnetic form factor of the pion in an optimized way, so that we obtain a value closer to the experimental charge radius of the pion. The theoretical calculations are also compared with the most recent experimental data involving the pion electromagnetic form factor and the results show very good agreement.Comment: Paper with 4 pages, 1 figure, presented in XII HADRON PHYSICS Conference - to appear in AIP Conference Proceeding

Quintessential inflation from 5D warped product spaces on a dynamical foliation

Assuming the existence of a 5D purely kinetic scalar field on the class of warped product spaces we investigate the possibility of mimic both an inflationary and a quintessential scenarios on 4D hypersurfaces, by implementing a dynamical foliation on the fifth coordinate instead of a constant one. We obtain that an induced chaotic inflationary scenario with a geometrically induced scalar potential and an induced quasi-vacuum equation of state on 4D dynamical hypersurfaces is possible. While on a constant foliation the universe can be considered as matter dominated today, in a family of 4D dynamical hypersurfaces the universe can be passing for a period of accelerated expansion with a deceleration parameter nearly -1. This effect of the dynamical foliation results negligible at the inflationary epoch allowing for a chaotic scenario and becomes considerable at the present epoch allowing a quintessential scenario.Comment: 7 pages, 1 figure Accepted for publication in Modern Physics Letters

Toxicological Study Employing Repeated Doses of Garcinielliptone FC, a Polyisoprenylated-Benzophenone Isolated from Seed of Platonia Insignis Mart

The major constituent from the hexane extract of the seeds of P. insignis is GFC (garcinielliptone FC). Doses of 25, 50and 75 mg/kg of GFC were aseptically suspended in 0.05% Tween 80 dissolved in 0.9% saline (vehicle) and orally administered for30, 90 and 120 consecutive days to adult Swiss mice. In this work, the repeated oral administration, in animals of both sexes,demonstrates that this compound is not able to induce mortality and/or behavioral changes in adult mice. In addition, body weightgain, feed intake and disposal of excreta were not altered by the administration of this compound with repeated doses. Furthermore,no differences in weight and macroscopic structure of the brain, liver, kidney, lung, heart and spleen between groups of male andfemale adult mice were observed after treatment. During the periods of treatment, GFC produced no significant changes onhaematological and biochemical parameters in male and female mice treated with all doses used. The aim of this study was toinvestigate the toxicological potential of GFC through behavioral, hematological, biochemical and morphological parameters inanimals in order to ensure the safe use of Platonia insignis in folk medicine.Fil: Silva, Ana P.. Federal University of Piauí; BrasilFil: Filho, José Carlos C. L. S.. North Union of Parana; BrasilFil: da Costa Júnior, Joaquim S.. Federal Institute of Piauí; BrasilFil: Peláez, Walter José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Faillace, Martín Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Falcão Ferraz, Alexandre de B.. Lutheran University of Brazil; BrasilFil: David, Jorge M.. Institute Of Chemistry, Federal University Of Bahia; Brasil. Universidade Federal da Bahia; BrasilFil: Freitas, Rivelilson M.. Federal University of Bahia; Brasi

Methodological considerations in assessing interlimb coordination on poststroke gait: a scoping review of biomechanical approaches and outcomes

To identify and summarize biomechanical assessment approaches in interlimb coordination on poststroke gait. Interlimb coordination involves complex neurophysiological mechanisms that can be expressed through the biomechanical output. The deepening of this concept would have a significant contribution in gait rehabilitation in patients with an asymmetric neurological impairment as poststroke adults. Poststroke adults (>19 years old), with assessment of interlimb coordination during gait, in an open context, according to the Population, Concept, Context framework. A literature search was performed in PubMed, Web of Science™, Scopus, and gray literature in Google Scholar™, according to the PRISMA-ScR recommendations. Studies written in Portuguese or English language and published between database inception and 14 November 2021 were included. Qualitative studies, conference proceedings, letters, and editorials were excluded. The main conceptual categories were “author/year”, “study design”, “participant’s characteristics”, “walking conditions”, “instruments” and “outcomes”. The search identified 827 potentially relevant studies, with a remaining seven fulfilling the established criteria. Interlimb coordination was assessed during walking in treadmill (n = 3), overground (n = 3) and both (n = 1). The instruments used monitored electromyography (n = 2), kinetics (n = 2), and kinematics (n = 4) to assess spatiotemporal parameters (n = 4), joint kinematics (n = 2), anteroposterior ground reaction forces (n = 2), and electromyography root mean square (n = 2) outcomes. These outcomes were mostly used to analyze symmetry indices or ratios, to calculate propulsive impulse and external mechanical power produced on the CoM, as well as antagonist coactivation. Assessment of interlimb coordination during gait is important for consideration of natural auto-selected overground walking, using kinematic, kinetic, and EMG instruments. These allow for the collection of the main biomechanical outcomes that could contribute to improve better knowledge of interlimb coordination assessment in poststroke patients.info:eu-repo/semantics/publishedVersio

Mobile laboratories as an alternative to conventional remote laboratories

Remote laboratories have been playing an important role on the improvement of flexibility and the extent of practical activities in teaching and learning activities in engineering and technology. However, the current remote laboratories model does not consider dynamic scenarios including collaboration, peer-to-peer labs and mobile labs. This paper presents a set of tools for creating collaborative online mobile laboratories that allow students to develop their own labs and share them with classmates and teachers. The approach used is compatible with the machine and network configurations that the target user has in schools and at home, and provides the retrieval of information for learning evaluation.info:eu-repo/semantics/publishedVersio

MODELO QUÂNTICO DO ÁTOMO: UMA ANÁLISE DO ENSINO DAS NOÇÕES DE QUANTUM DE UMA GRANDEZA E COMPORTAMENTO DUAL DA ENERGIA E DA MATÉRIA

Partindo do pressuposto de que as noções de quantum de uma grandeza e de comportamento dual (onda/partícula) da radiação e da matéria são dois aspectos básicos para a compreensão de um sistema quântico — a exemplo do átomo — este trabalho teve como objetivo analisar livros didáticos de Químicapara o ensino médio, aprovados no PNLD para 2012, no que se refere a tais conteúdos. Os resultados revelam insuficiências na elaboração do texto de todos os materiais analisados, principalmente relacionadas falta de clareza dos conceitos da teoria quântica e de articulação com outras informações apresentadas anteriormente no próprio texto. Concluímos, portanto,pela necessidade de detalhamento e aprofundamento dos textos didáticos de química no que se refere aos conteúdos em foco

A linguagem química e o ensino da química orgânica

The importance of chemical language and specifically of molecular models and their representations in the development of chemistry is discussed. Structural formulas are projections of molecular models used as a specific language by chemists. The meaningful learning of chemistry requires knowledge of this language. The use of these analogical symbols without the necessary understanding engenders difficulties for the learning of chemistry

Efficiency of triple emitter source (TES) for irrigation experiments of horticultural crops

Triple emitter source TES experimental irrigation was designed. Three trickle laterals were connected together in order to form a triple joint lateral. Two of them and their emitters are connected to two tanks of stock solutions. The third lateral contains only fresh water. The emitters of the two solution lines have different and varying discharges to obtain several mixings of the two stock solutions. The third line is necessary to obtain constant water application rates for each trickling point along the lateral. This method was tested for several experiments involving the study of the combined effects of salinity and fertilizers on the yield function of horticultural crops, namely lettuce and cabbage. As concluding remarks, it was shown the high uniformity of the factor to be evaluated, through the use of Christiansen coefficient of uniformity distribution CUC, which value was always larger than 90%. Main advantage of this experimental design is its smaller experimental plots (reducing pollution and research costs)

O ensino e a aprendizagem do conceito químico de substância como material puro

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