Quantum Electro and Chromodynamics treated by Thompson's heuristic approach

In this work we apply Thompson's method (of the dimensions and scales) to study some features of the Quantum Electro and Chromodynamics. This heuristic method can be considered as a simple and alternative way to the Renormalisation Group (R.G.) approach and when applied to QED-lagrangian is able to obtain in a first approximation both the running coupling constant behavior of alpha(mu) and the mass m(mu).The calculations are evaluated just at d_c=4, where d_c is the upper critical dimension of the problem, so that we obtain the logarithmic behavior both for the coupling alpha and the excess of mass Delta m on the energy scale mu. Although our results are well-known in the vast literature of field theories,it seems that one of the advantages of Thompson's method, beyond its simplicity is that it is able to extract directly from QED-lagrangian the physical (finite) behavior of alpha(mu) and m(mu), bypassing hard problems of divergences which normally appear in the conventional renormalisation schemes applied to field theories like QED. Quantum Chromodynamics (QCD) is also treated by the present method in order to obtain the quark condensate value. Besides this, the method is also able to evaluate the vacuum pressure at the boundary of the nucleon. This is done by assumming a step function behavior for the running coupling constant of the QCD, which fits nicely to some quantities related to the strong interaction evaluated through the MIT-bag model.Comment: RevTex, 25 pages, no figure

Variation of the speed of light with temperature of the expanding universe

From an extended relativistic dynamics for a particle moving in a cosmic background field with temperature T, we aim to obtain the speed of light with an explicit dependence on the background temperature of the universe. Although finding the speed of light in the early universe much larger than its current value, our approach does not violate the postulate of special relativity. Moreover, it is shown that the high value of the speed of light in the early universe was drastically decreased before the beginning of the inflationary period. So we are led to conclude that the theory of varying speed of light should be questioned as a possible solution of the horizon problem.Comment: 3 pages and 1 figure; Phys. Rev. D86, 027703 (2012

Doubly Special Relativity with a minimum speed and the Uncertainty Principle

The present work aims to search for an implementation of a new symmetry in the space-time by introducing the idea of an invariant minimum speed scale ($V$). Such a lowest limit $V$, being unattainable by the particles, represents a fundamental and preferred reference frame connected to a universal background field (a vacuum energy) that breaks Lorentz symmetry. So there emerges a new principle of symmetry in the space-time at the subatomic level for very low energies close to the background frame ($v\approx V$), providing a fundamental understanding for the uncertainty principle, i.e., the uncertainty relations should emerge from the space-time with an invariant minimum speed.Comment: 10 pages, 8 figures, Correlated paper in: http://www.worldscientific.com/worldscinet/ijmpd?journalTabs=read. arXiv admin note: substantial text overlap with arXiv:physics/0702095, arXiv:0705.4315, arXiv:0709.1727, arXiv:0805.120

LESÕES SERRILHADAS SUPERFICIAIS NAS FASES INICIAIS SÃO HIPERPLÁSICAS OU LESÕES SÉSSEIS SERRILHADAS?

BACKGROUND: At least 20% of colorectal adenocarcinomas arise through serrated lesions and studying them in early stages is important in prevention. AIM: To analyze and compare the endoscopic and histopathological characteristics of superficial serrated lesions in early stages, greater than 5 mm in length, completely resected during colonoscopies, and classified. METHOD: Retrospective and observational study evaluating 12,653 colonoscopy exams where 217 cases were selected that underwent endoscopic resections of superficial serrated lesions measuring more than 5 mm in diameter, addressed in terms of anatomical location, endoscopic findings, the average size of the lesions, average age, gender, and anatomopathological result. RESULTS: There were 2 groups G1 and G2. G1 had 126 hyperplastic lesions (HL) and G2 had 91 sessile serrated lesions. The anatomical location was 57.9% proximal and 42.1% distal in G1 and 94.5% and 5.5% respectively in G2. In G1, type 0-IIa was found in 26.2% and lateral spreading in 73.8%; in G2, 15.4% and 84.6%, respectively. The average size of the lesions in G1 was 15.4 mm and in G2, 16.7 mm. The average age G1 was 62.6 and G2, 63.5. Women were predominant in the total number of patients. No invasive adenocarcinomas were observed in the 2 groups. CONCLUSIONS: Superficially elevated serrated lesions, measuring more than 5 mm and resected by colonoscopies, were hyperplastic (58%). HL was observed throughout the colon and rectum and SSL was predominantly in the proximal colon. HL did not present dysplasia and SSL did. No invasive adenocarcinomas were observed in the submucosa.RACIONAL: Pelo menos 20% dos adenocarcinomas colorretais surgem através de lesões serrilhadas e estudá-los em estágios iniciais é importante na prevenção. OBJETIVO: Analisar e comparar as características endoscópicas e histopatológicas de lesões superficiais serrilhadas em estágios iniciais, maiores que 5 mm de comprimento, completamente ressecadas durante colonoscopias e classificadas. MÉTODO: Estudo retrospectivo e observacional avaliando 12.653 exames de colonoscopia, onde foram selecionados 217 casos submetidos às ressecções endoscópicas de lesões superficiais serrilhadas medindo mais de 5 mm de diâmetro, abordados quanto à localização anatômica, achados endoscópicos, tamanho médio das lesões, idade média, sexo e resultado anatomopatológico. RESULTADOS: Houve 2 grupos, G1 e G2. O G1 apresentou 126 lesões hiperplásicas (HL) e o G2 91 lesões serrilhadas sésseis. A localização anatômica foi 57,9% proximal e 42,1% distal no G1 e 94,5% e 5,5% respectivamente no G2. No G1, o tipo 0-IIa foi encontrado em 26,2% e o espalhamento lateral em 73,8%; no G2, 15,4% e 84,6%, respectivamente. O tamanho médio das lesões G1 foi de 15,4 mm e G2 de 16,7 mm. A média de idade do G1 foi de 62,6 anos e do G2, 63,5 anos. As mulheres predominaram no total de pacientes. Não foram observados adenocarcinomas invasivos nos 2 grupos. CONCLUSÕES: Lesões serrilhadas superficialmente elevadas, medindo mais de 5 mm e ressecadas por colonoscopia, eram hiperplásicas (58%). O HL foi observado em todo o cólon e reto e o SSL foi predominantemente no cólon proximal. HL não apresentou displasia e SSL sim. Não foram observados adenocarcinomas invasivos na submucosa

Da gestão de TI à gestão de informação e tecnologia: uma abordagem teórica da evolução do conceito = From management of technology and information to a management of information and technology : a theoretical approach of concept development

Este trabalho tem por objetivo reavaliar o conceito do alinhamento das ferramentas detecnologia da informação e comunicação (TIC) com a gestão estratégica das empresas, visandoinverter a lógica atual ao mostrar que, primeiro deve-se pensar na gestão de informação econhecimento alinhado ao modelo de negócio da organização; somente depois escolher as ferramentasque suportarão a estratégia adotada. Foi utilizada como metodologia uma análise de referencialteórica, visando dar embasamento aos conceitos apresentados. Além disso, é apresentado um modelo,que permite aos gestores realizarem uma análise da situação atual da organização em relação aoalinhamento da gestão da informação e do conhecimento com a gestão estratégica. O modelo permiteperceber a importância de evoluir o alinhamento o estratégico na busca de melhoria no desempenhoorganizacional.This paper aims to reevaluate the concept of communication and information technologytools (CIT) alignment with companies strategic management, aiming to reverse the current logic,showing that first companies must think about the alignment of the information and knowledgemanagement with the organization's business model; only after this the tools, that will support thestrategy adopted, must be chosen. A theoretical framework methodology analysis was used aiming toprovide the foundation concepts presented. In addition, a model is presented, which allows managersto carry out an analysis of the current situation of the organization, related to the alignment ofinformation and knowledge management with strategic management. The model allows theunderstanding of the importance of alignment strategic evolving in order to seek organizationalperformance improvement

Deformed Special Relativity with an energy barrier of a minimum speed

This research aims to introduce a new principle in the flat space-time geometry through the elimination of the classical idea of rest and by including a universal minimum limit of speed in the quantum world. This limit, unattainable by the particles, represents a preferred inertial reference frame associated with a universal background field that breaks Lorentz symmetry. There emerges a new relativistic dynamics where a minimum speed forms an inferior energy barrier. One of the interesting consequences of the existence of such a minimum speed is that it prevents the absolute zero temperature for an ultracold gas according to the third law of thermodynamics. So we will be able to provide a fundamental dynamical explanation for the third law through a connection between such a phenomenological law and the new relativistic dynamics with a minimum speed.Comment: 14 pages, 4 figure