462 research outputs found
Constrained Analysis of Topologically Massive Gravity
We quantize the Einstein gravity in the formalism of weak gravitational
fields by using the constrained Hamiltonian method. Special emphasis is given
to the 2+1 spacetime dimensional case where a (topological) Chern-Simons term
is added to the Lagrangian.Comment: 15 pages, IF-UFRJ-21/9
Projeto e dimensionamento de um sistema de freio aplicado a um protótipo de veículo para competição fora de estrada
This course work aims to present the brake system design of a baja SAE prototype, presenting
all the stages of the project, as well as a justification of the selection of each of the components
of the system. To reduce the expenses of the system were used cost optimization tools. The
brakes can be activated in different ways, with the hydraulic drive being the most used. The
disc brake was selected for the design. Along with floating type brake calipers, which has the
advantage of compensating small bores on the disc. For the development of the low SAE
prototype, the Modular Function Deployment (MFD) was applied, which allows the designer
to choose the modular design from the reasons specified in the design. The Quality Function
Deployment (QFD) was applied in the improvement and improvement of the product, the
Engineering and Value Analysis (EAV) was applied, making it possible to determine the
components that have a high cost in relation to the function they perform. Finally the Design
for Manufacturing and Assembly (DFMA) was ideal to make a design of manufacture,
assembly of components during the assembly and maintenance of the system. The parts
selection was used as a parallel measurement with the design, to suit the needs of the project.
The present study made it possible to apply the knowledge acquired during the period in which
I was part of the Baja da Peste team, as well as everything that was seen in the classroom during
the course of mechanical engineering, thus contributing to my training.Este trabalho de conclusão de curso tem por objetivo apresentar o dimensionamento do sistema
de freio de um protótipo baja SAE, apresentando todas as etapas do projeto, bem como a
justificativa da seleção de cada componente deste sistema. Para redução das despesas do sistema
foram utilizadas ferramentas de otimização de custos. Os freios podem ser acionados de
diversas formas, sendo o acionamento hidráulico o mais utilizado. O freio a disco foi o
selecionado para o projeto. Juntamente com pinças do tipo flutuante, que tem como vantagem
compensar pequenos empenos no disco. Para desenvolvimento do protótipo baja SAE foi
aplicado o Desdobramento da Função Modular (MFD), que permite que o projetista escolha o
design modular a partir das razões especificadas no projeto. O Desdobramento da Função
Qualidade (QFD), foi aplicado no desenvolvimento e melhoria do produto, a Engenharia e
Análise do Valor (EAV) foi aplicada, possibilitando determinar os componentes que tem custo
elevado em relação a função que eles exercem. Por fim o Projeto para Manutenção e Montagem
(DFMA) foi aplicado ao projeto a fim de facilitar a fabricação, minimizar os erros durante a
montagem e manutenção do sistema. A seleção das peças a serem utilizadas foi feita de forma
paralela com o dimensionamento, de modo que atendessem as necessidades do projeto. O
presente estudo possibilitou aplicar os conhecimentos adquiridos no período em que fiz parte
da equipe Baja da Peste, bem como tudo que foi visto em sala de aula durante o curso de
engenharia mecânica, contribuindo assim para a minha formação
Support to woman by a companion of her choice during childbirth: a randomized controlled trial
<p>Abstract</p> <p>Background</p> <p>To evaluate the effectiveness and safety of the support given to women by a companion of their choice during labor and delivery.</p> <p>Methods</p> <p>A total of 212 primiparous women were enrolled in a randomized controlled clinical trial carried out between February 2004 and March 2005. One hundred and five women were allocated to the group in which support was permitted and 107 to the group in which there was no support. Variables regarding patient satisfaction and events related to obstetrical care, neonatal results and breastfeeding were evaluated. Student's t-test or Wilcoxon's test, chi-square or Fisher's exact test, risk ratios, and their respective 95% confidence intervals were used in the statistical analysis.</p> <p>Results</p> <p>Overall, the women in the support group were more satisfied with labor (median 88.0 versus 76.0, p < 0.0001) and delivery (median 91.4 versus 77.1, p < 0.0001). During labor, patient satisfaction was associated with the presence of a companion (RR 8.06; 95%CI: 4.84 – 13.43), with care received (RR 1.11; 95%CI: 1.01 – 1.22) and with medical guidance (RR 1.14 95%CI: 1.01 – 1.28). During delivery, satisfaction was associated with having a companion (RR 5.57, 95%CI: 3.70 – 8.38), with care received (RR 1.11 95%CI: 1.01 – 1.22) and with vaginal delivery (RR 1.33 95%CI:1.02 – 1.74). The only factor that was significantly lower in the support group was the occurrence of meconium-stained amniotic fluid (RR 0.51; 95%CI: 0.28 – 0.94). There was no statistically significant difference between the two groups with respect to any of the other variables.</p> <p>Conclusion</p> <p>The presence of a companion of the woman's choice had a positive influence on her satisfaction with the birth process and did not interfere with other events and interventions, with neonatal outcome or breastfeeding.</p
Pricing and quality investments in a mixed brown-green product market
Sustainable Supply Chain Management (SSCM) has assumed
a position of prominence for academics and industry over the last two
decades. The sustainability literature shows that typically manufacturers aim to optimize their pricing and greening level decisions in a mixed
(green and brown) consumer market. In this work, we capture a manufacturer’s classic dilemma on the pricing of green and brown products,
and greening investments, while subject to budget constraint. We compute and analyze the variations of optimal decisions over time. Our findings underscore the importance of investing in greening technologies and
learning for the survival of green products. Furthermore, we show that
a manufacturer’s optimal pricing strategy is to enter the market with
a lower price for the green product and to increase it over time, eventually, surpassing the price for the brown product. Our analysis reveals
that the greening level attraction can nullify the effect of a high price on
the green product, resulting in higher green demand than brown. Higher
green product demand is a win-win situation for both the manufacturer
and the environment
Existem relações entre tamanho e morfoecogenicidade do corpo lúteo detectados pelo ultra-som e os teores de progesterona plasmática em receptoras de embriões eqüinos?
Corpus luteum (CL) synthesizes progesterone (P4), which has a major function in maintenance of pregnancy in equine females and also enables the application of biotechnologies of reproduction. Considering the importance of the CL and its anatomical and physiological features to achieve normal pregnancy, our aims were to determine the size and morphoechogenicity (ME), as well as plasma P4 concentrations of corpus luteum from recipient mares for nine days after ovulation (D0). Therefore, 57 recipient mares were examined daily by transrectal ultrasonography (US) from early signals of estrus to D9. CLs were measured and their ME classified according to a 1 to 6 scale (1=anechogenic; 6=hiperechogenic). Blood samples were collected daily and progesterone concentrations assessed by radioimmunoassay. Pregnancies were checked by US 13 and 25 days after ovulation. Corpus luteum echogenicity had a tendency to increase from D0 to D9. Progesterone concentrations were < 2,16 ng/ml until D3, but there was a significant elevation from D4 to D9 (3,41 to 4,33 ng/ml). There were no differences in CL size, except between D2 (31,54 mm) and D8 (25,95 mm); p < 0,05). Thus, an increase in mean luteal ME is accompanied by an increase in plasmatic P4 concentration, but this event seems independent of luteal size. There were no differences between ME, size and P4 levels from D0 to D9 in recipient mares that became pregnant or not after embryo transfer.O corpo lúteo (CL) é a glândula produtora de progesterona (P4), hormônio cuja secreção contínua é essencial para o início e a manutenção da gestação em fêmeas eqüinas, e, conseqüentemente, para a aplicabilidade de inúmeras biotécnicas de reprodução. Considerando-se a importância do CL para a manutenção de uma gestação normal e suas características anatomofisiológicas, objetivou-se determinar por ultra-sonografia (US) o tamanho e a morfoecogenicidade (ME) do CL em receptoras de embriões eqüinos desde a ovulação (D0) até nove dias após (D9), bem como os níveis plasmáticos de P4 produzida no mesmo período. Para tanto, 57 éguas receptoras de um programa de transferência de embriões foram examinadas diariamente por US transretal desde a primeira detecção dos sinais de estro até o D9. A cada exame, os CL foram mensurados e sua ME registrada segundo escore de 1 a 6 (1=anecóico; 6=hiperecóico). Amostras de sangue foram colhidas diariamente e a P4 dosada por radioimunoensaio. O diagnóstico de gestação foi realizado por US aos 13 e 25 dias após a ovulação. Houve uma tendência de os corpos lúteos apresentarem ME crescente (de 1 a 5) desde o dia da ovulação até o D9. Os níveis de P4 foram < 2,16 ng/ml até o D3, com conseqüente elevação e manutenção em níveis de diestro entre D4 e D9 (3,41 a 4,33 ng/ml). O tamanho luteínico não diferiu, com exceção das médias extremas durante o período (D2 = 31,54 mm versus D8 = 25,95mm; p < 0,05). Assim, o aumento da ME média dos CLs avaliados por US é acompanhado por aumento na concentração plasmática de P4 em receptoras de embriões, mas este evento parece não ser dependente do tamanho da glândula luteínica. Não existe diferença na ME, no tamanho dos corpos lúteos, nem nos níveis de P4 circulante do D0 ao D9 em receptoras de embriões eqüinos que se tornaram gestantes ou não após a transferência de embriões
Singular Fermi Liquids
An introductory survey of the theoretical ideas and calculations and the
experimental results which depart from Landau Fermi-liquids is presented.
Common themes and possible routes to the singularities leading to the breakdown
of Landau Fermi liquids are categorized following an elementary discussion of
the theory. Soluble examples of Singular Fermi liquids (often called Non-Fermi
liquids) include models of impurities in metals with special symmetries and
one-dimensional interacting fermions. A review of these is followed by a
discussion of Singular Fermi liquids in a wide variety of experimental
situations and theoretical models. These include the effects of low-energy
collective fluctuations, gauge fields due either to symmetries in the
hamiltonian or possible dynamically generated symmetries, fluctuations around
quantum critical points, the normal state of high temperature superconductors
and the two-dimensional metallic state. For the last three systems, the
principal experimental results are summarized and the outstanding theoretical
issues highlighted.Comment: 170 pages; submitted to Physics Reports; a single pdf file with high
quality figures is available from http://www.lorentz.leidenuniv.nl/~saarloo
Health surveillance and agribusiness: the impact of pesticides on health and the environment. Danger ahead!
Effect of singing training on total laryngectomees wearing a tracheoesophageal voice prosthesis
Chemical inhibition of the contaminant Lactobacillus fermentum from distilleries producing fuel bioethanol
Retrospective study of 151 patients with cutaneous leishmaniasis treated with meglumine antimoniate
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