Air velocity and exposure time to ventilation affect body surface and rectal temperature of broiler chickens

Increasing air movement over poultry by using fans (ventilation) has become an accepted means of reducing environmental heat stress over the last several years. The purpose of this study was to evaluate the effect of air velocity and exposure time to ventilation on body surface and rectal temperature of broiler chickens. Male broiler chickens aged 36-42 days were placed in individual wire cages and exposed to five different air velocities (5.7, 4.2, 3.1, 2.4, or 1.8 m/sec). Throughout the experiment head, back, leg, and rectal temperatures were monitored every 10 min during a 30-min period for each air velocity. The data showed that exposure time to the wind affected (P<.05) leg and body temperature, with a rapid reduction being observed during the first 10 min. There was a reduction in leg temperature with air velocity of 2 m/sec; however, air velocity lower than 4.5 m/sec was not effective in decreasing head and back temperature. The results suggest that air velocity of 2 m/sec, in air temperature of 29 degrees C, improves heat loss in the birds. The data also indicate that exposure time to ventilation seems to be a critical point in the maintenance of bird thermal homeostasis.

Analysis of the four wave mixing effect (FWM) in a dispersion decreasing fiber (DDF) for a WDM system

We did a numerical investigation of the propagation of short light pulses in the region of 1.55 mu m and the conversion efficiency (CE) for the four wave mixing generation (FWM) of ordinary and dispersion decreasing fibers for use in wavelength division multiplexing (WDM) systems, Our simulations studies three different profiles, linear, hyperbolic. and constant, One conclude that for all the profiles there is decrease of the conversion efficiency with the increase in the channel separation. The hyperbolic profile present a higher efficiency of around 1000 above in magnitude compared with the others profiles at 0.2 nm of channel separation. We calculate the conversion efficiency versus the fiber length for the three profiles. The conversion efficiency for the hyperbolic profile is higher when compared to the constant and linear profiles. The other interesting point of the hyperbolic profile is that the increase of the CE in the beginning of the fiber does not show my oscillation in the CE value (log eta), which was observed for the constant and linear profiles. For all the profiles there is an increase of the conversion efficiency with the increase of the pump power. The compression factor C-i for the generated FWM signal at omega(3) was measured along the DDF's and the constant profile fibers. One can conclude that with the use of decreasing dispersion profile (DDF) fibers one can have a control of the (CE) conversion efficiency and the compression factor of the four wave mixing (FWM) generation in WDM systems. (c) 2005 Elsevier B.V. All rights reserved.

Gravitational Capture of Asteroids by Gas Drag

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Model for determining flow diameter and economic velocity in water elevating systems

The purpose of this paper was to develop a model for calculating the economical flow diameter and velocity, by obtaining the economical diameter, using Swamee's friction factor equation, by minimizing the total annual cost. The application of the model to a regular supply condition showed that the diameter of the actual condition, 250 mm, compared with the diameter calculated by the mode, at the same tariff as that applied to the property ( ground), 284.1 mm, involved the necessity to generate, transmit, and distribute extra electrical energy, due to the higher load loss caused by the original diameter, approximately 30800 kWh/year. This means that in one year, the consumer would spend R$2,804.00 more on pumping cost alone.

Beneficial effects of diclofenac therapy on serum lipids, oxidized low-density lipoprotein and antioxidant defenses in rats

To study the effects of diclofenac, a nonselective nonsteroidal anti-inflammatory drug (NSAID), on lipid profile, oxidized low-density-lipoprotein (Ox-LDL), serum antioxidant defenses and markers of oxidative stress, male Wistar rats were divided into two groups (n = 10): (C) receiving intramuscularly a single daily dose of saline (NaCl 0.9%), and (AI) receiving intramuscularly a single daily dose of 10 mg/kg diclofenac sodium (C14H10C12NNaO2). After 28 days diclofenac-treated rats had lower Ox-LDL, apoprotein B (apo-B), apo-B/LDL-cholesterol and lipid hydroperoxide than C. Total antioxidant substances and superoxide dismutase were increased in diclofenac-treated rats, while no significant changes were observed in catalase, glutathione peroxidase and nitric oxide. A perincubation test done to examine the possibility of mechanism-based activation showed that diclofenac had no effect on maximal superoxide dismutase velocity, but significantly reduced the Michaelis-Menten (K-M) constant, indicating that diclofenac induced SOD activation increasing substrate linkage affinity to the enzyme-catalytic site. In conclusion, diclofenac had beneficial effects decreasing Ox-LDL and improving antioxidant defense. It appears that the application of this agent may be feasible and beneficial for serum antioxidant protection, which certainly would bring new insights on dyslipidemia control. (C) 2008 Elsevier B.V. All rights reserved.

A mass-transportation approach to a one dimensional fluid mechanics model with nonlocal velocity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeitos da autoclavação na velocidade e capacidade absorvente de cones de papel empregados em Endodontia

A presença de umidade no interior do sistema de canais radiculares, após o preparo biomecânico e sua desinfecção, pode influenciar no selamento apical e no êxito da obturação endodôntica. O objetivo deste trabalho foi avaliar a influência do número de esterilizações em autoclave, sobre a capacidade e velocidade de absorção dos cones de papel empregados em Endodontia. Foram analisados 440 cones de papel número 40, dos quais dez cones de cada marca comercial receberam de zero à dez ciclos de esterilização em autoclave (134°C/15 psi/15 minutos). Após cada ciclo de esterilização, os cones foram avaliados quanto a capacidade e velocidade de absorção de solução de hipoclorito de sódio a 1%. Os dados foram submetidos à análise estatística por meio dos testes da ANOVA (dois critérios) e Tukey (5%). Pôde-se concluir que, quanto à capacidade de absorção, os cones que sofreram menor influência dos diversos ciclos de esterilização em autoclave foram, em ordem decrescente: Tanari, Tanari cell pack, Conne e Diadent cell pack. Quanto à velocidade de absorção, os cones que obtiveram os melhores resultados foram: Tanari cell pack, Tanari, Conne e Diadent cell pack. A autoclavação mostrou-se um procedimento viável, em até 10 ciclos, apenas para a esterilização de cones de papel absorvente da marca Tanari utilizados em Endodontia.

Dynamical properties for the problem of a particle in an electric field of wave packet: Low velocity and relativistic approach

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Velocity-dependent KAM islands

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A Short Note on Transverse Vibrations of a Shaft Carrying Two (or One) Disk Excited by a Nonideal Motor

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Experimental aspects of biomass fuels in a bubbling fluidized bed combustor

This work presents experimental information relevant to the combustion of biomass in a bubbling fluidized bed. The biomass distribution in a fluidized bed was studied through tests performed in a cold bed, while the volatiles released in the biomass pyrolysis, the burning rate of the resulting charcoal, and the combustion control regime, were studied through tests performed in a high temperature bed.Visual examination of photographs taken from a transparent walls bed, with a rectangular cross-section, showed that the large fuel particles, typical of biomass processing, were distributed in the bubbles, in the splash zone, and in the emulsion phase. The occurrence of biomass in the emulsion phase was favored by burning biomass particles of greater density and smaller size-expetimentally determined in each case. Decreasing the fuel particle size improved the biomass distribution inside the bed. The same was accomplished by increasing the superficial gas velocity as high as possible, compatibly with the acceptable elutriation.Burning tests showed that the biomass fuels have the advantage of reaching the diffusional regime at temperatures that can be lower than 1000 K, which ensures that the biomass fuels burn in a stable regime. (C) 2007 Elsevier B.V. All rights reserved.

High-velocity oxyfuel Cr3C2-NiCr replacing hard chromium coatings

Comparative wear and corrosion properties of Cr3C2-NiCr (CC-TS) (a high-velocity oxyfuel [HVOF]) and hard chromium (HC) coating's obtained on a steel substrate have been studied. The structural characterization was done before and after measurements by optical microscopy, scanning electron microscopy, and scanning white light interferometry. Wear and corrosion properties were evaluated by ball on disk (ASTM G99-90), rubber wheel (ASTM G65-91), and electrochemical measurements of open circuit and polarization curves. The best corrosion and wear resistance was for the CC-TS obtained by HVOF. The open-circuit potential values measured for both samples after 18 h of immersion we're: -0.240 and -0.550 V, respectively, for CC-TS and HC, versus Ag/AgCl,KClsat. Three orders of magnitude lower volume loss were found for CC-TS (HVOF) after friction tests compared with HC.

WC-CoCr coatings sprayed by high velocity oxygen-fuel (HVOF) flame on AA7050 aluminum alloy: electrochemical behavior in 3.5% NaCl solution

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Broiler litter reutilization applying different composting concepts

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Desempenho operacional de trator com e sem o acionamento da tração dianteira auxiliar

Entre os fatores que podem influenciar o desempenho de tração do trator agrícola, destacam-se a pressão de inflação e a carga sobre o rodado motriz. Neste trabalho, o objetivo foi avaliar, em situação de campo, a influência dos fatores inflação (sob quatro níveis) e carga sobre o rodado motriz (sob quatro níveis), combinados com e sem o uso da tração dianteira auxiliar. O experimento, totalizando 32 tratamentos com três repetições, foi distribuído em blocos ao acaso. O trator estudado foi submetido a uma força de tração constante na barra de tração, imposta por outro trator. Os resultados evidenciaram a influência significativa da lastragem nos parâmetros patinagem e coeficiente de tração, que aumentaram com a redução da carga sobre o rodado. A pressão de inflação influiu significativamente nos parâmetros patinagem, velocidade de deslocamento e potência na barra, sem no entanto apresentar tendência de comportamento. O uso da tração dianteira auxiliar mostrou vantagens significativas em relação aos mesmos parâmetros anteriores. A interação dos fatores pressão de inflação e carga sobre o rodado mostrou que determinadas combinações de pressão foram mais favoráveis para o desenvolvimento de maior velocidade e menor patinagem. As características relacionadas ao desempenho do motor (consumo horário e rotação do motor) não foram afetadas por nenhum dos fatores e/ou suas interações.