12,704 research outputs found
Dirac quantization of a nonminimal gauged O(3) sigma model
The (2+1) dimensional gauged O(3) nonlinear sigma model with Chern-Simons
term is canonically quantized. Furthermore, we study a nonminimal coupling in
this model implemented by means of a Pauli-type term. It is shown that the set
of constraints of the model is modified by the introduction of the Pauli
coupling. Moreover, we found that the quantum commutator relations in the
nominimal case is independent of the Chern-Simons coefficient, in contrast to
the minimal one.Comment: 7 pages, to appear in Modern Physics Letters
Measurement tools to assess education and psychosocial support of pulmonary rehabilitation in people with chronic obstructive pulmonary disease: a systematic literature review
Introduction and objectives: Education and psychosocial support is a core component of pulmonary rehabilitation (PR). Nevertheless, measurement tools used to assess the effects of this component of
PR have been scarcely investigated. Thus, this systematic literature review aimed to identify which measurement tools have been used to assess education and psychosocial support of PR in people with chronic obstructive pulmonary disease (COPD.) Methods: A systematic search was conducted on PubMed, Scopus and Web of Science in February 2021. Articles were screened and inclusion decided by two independent researchers. Randomised control studies, quasi-experimental and pre-post studies, which included people with COPD enrolled in a PR programme, with exercise and education and psychosocial support, were included. The same two independent researchers extracted the data to a standardised table. Results: A total of 7112 studies were screened and 9 studies were included. 1121 people with COPD (68.69 ± 8.98 years old, 30.78% female, FEV1pp 53.25 ± 19.04%) were enrolled in the included studies. A total of 9 measurement tools were identified and the most reported was the Bristol COPD Knowledge Questionnaire (BCKQ) (n = 3, 33.3%). Other measurement tools were found, such as the Patient Activation Measure (PAM) (n = 1, 11.1%), the Education Specific Questionnaire (ESQ) (n = 1, 11.1%), the Lung Information Needs Questionnaire (LINQ) (n = 1, 11.1%), the COPD Knowledge Test (n = 1, 11.1%), the Pulmonary Disease Knowledge Test (PDKT) (n = 1, 11.1%), the Health Education Impact Questionnaire (heiQ) (n = 1, 11.1%), the Understanding COPD Questionnaire (UCOPD) (n = 1, 11.1%) and the Knowledge Assessment Questionnaire (n = 1, 11.1%). Conclusions: This review has shown that there are nine measurement tools available to assess the effects of education and psychosocial support of PR in people with COPD. The most reported has been the BCKQ however, few studies assessing this component in PR programmes have been conducted. Given the importance of education and psychosocial support of PR for people with COPD, future research is urgently needed to provide recommendations on the most suitable measurement tools and promote its routine assessment.publishe
The Minimal Landau Background Gauge on the Lattice
We present the first numerical implementation of the minimal Landau
background gauge for Yang-Mills theory on the lattice. Our approach is a simple
generalization of the usual minimal Landau gauge and is formulated for general
SU(N) gauge group. We also report on preliminary tests of the method in the
four-dimensional SU(2) case, using different background fields. Our tests show
that the convergence of the numerical minimization process is comparable to the
case of a null background. The uniqueness of the minimizing functional employed
is briefly discussed.Comment: 5 pages, 1 tabl
Sigatoka-negra e ferrugem-asiática: duas doenças de grande impacto econômico.
Duas doenças têm merecido especial atenção do Ministério da Agricultura e Abastecimento (MAPA): A Sigatoka-negra da banana e a Ferrugem-asiática da soja, causadas, pelos respectivos fungos exóticos atuais, Mycosphaerella fijiensis M. Morelet (Paracercospora fijiensis (M. Morelet) Deighton) e Phakopsora pachyrhizi Sydow & P. Sydow. Estes foram, recentemente, introduzidos no PaÃs, sendo que, o primeiro tem distribuição restrita e o segundo se encontra amplamente disseminado no território brasileiro.bitstream/CENARGEN/27989/1/doc167.pd
The Impact of High Particles Concentration in a Biofuel Droplet Combustion
Aviation is one of the largest transportation sectors and is operated on fossil fuels, being responsible for about 2% of global CO2 emissions. In order to reduce the environmental impact, biofuels emerged as a promising solution. Additionally, a possible approach to improve the performance of biofuels is to add nanoparticles, leading to the concept of nanofuel. The present work evaluates the nanofuel droplet combustion of a biofuel containing high aluminum particle concentrations. To enhance the nanofuel stability, a preliminary study focusing on the addition of a surfactant was mandatory. Particle size of 40 nm and three particle concentrations from 1.0 to 4.0 wt.% were considered. The results show that the oleic acid effectively improves the stability, and no visible oxidation of the nanoparticles was reported. Regarding the single droplet combustion, the observations show that the addition of nanoparticles promotes micro-explosions, contrary to the combustion of pure biofuel, and increases the overall droplet burning rate.Fundação para a Ciência e a Tecnologiainfo:eu-repo/semantics/publishedVersio
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