Loss compensation in microring-based Si photonics devices via Er3+doped claddings

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOWe propose and demonstrate a method to compensate insertion losses in Si photonics devices based on ring resonators fabricated in SOI foundries, with no additional chip area used. It consists in the employment of Er:Al2O3 as the upper cladding layer on standard Si/SiO2 rings, requiring only one simple post-processing step. The method is modeled in detail, and simulation results for single-ring configurations and photonic molecules are discussed, where the potential for loss reduction is predicted for different design choices based on the quality factor. We experimentally verify the viability of the method, obtaining an output power increase of 1 dB when a single-ring resonator is pumped. This value is increased when the method is applied to devices based on photonic molecules, where a value of 2.6 dB has been measured. This is equivalent to a loss reduction potential higher than 3 dB for a photonic molecule designed to achieve a quality factor of 50000.104113FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO08/57857-22014/04748-2574017/2008-

Profile of Producers and Production of Dry-Aged Beef in Brazil

No information is currently available on the profile of producers and production process of dry-aged beef in Brazil, to the best of the authors’ knowledge. We surveyed 37 Brazilian companies that were producing dry-aged beef in 2020 to investigate this market. The absolute and relative frequency of responses was calculated to obtain the sum, average, minimum, and maximum values. From the respondents, dry-aged beef was first produced in 2009, and most producers are located in big cities. Most respondents control and monitor chamber temperature; however, humidity and air velocity only are monitored. The aging period (mostly between 22 to 60 days) was the main indicator of product readiness. The process losses (water loss and crust trimming) can reach 65%. Some producers perform microbiological analyses to ensure product safety and others use tools such as GMP and SOP. The results of this survey may help governmental institutions to develop a standardized industrial protocol for producing dry-aged beef in Brazil

Desempenho de luta e sobrevivência entre espécies de abelhas sem ferrão e abelhas africanizadas em confinamento.

Este estudo avaliou o desempenho de luta e a sobrevivência de três espécies de abelhas sem ferrão confinadas com abelhas africanizadas (Apis mellifera)

Coleta de recursos e atividade externa de abelhas campeiras de Scaptotrigona sp. e Plebeia aff. flavocincta (Hymenoptera, Apidae, Meliponini) no Semiárido da Caatinga.

Este trabalho avaliou a qualidade de recursos e a atividade externa de abelhas campeiras de Scaptotrigona sp. e Plebeia aff. flavocincta na Caatinga

Acute exercise induce endothelial nitric oxide synthase phosphorylation via Akt and AMP-activated protein kinase in aorta of rats: Role of reactive oxygen species

AbstractBackgroundAcute exercise increases reactive oxygen species (ROS) levels, including hydrogen peroxide (H2O2). H2O2 promotes endothelial nitric oxide synthase (eNOS) activation and phosphorylation in endothelial cells. With this in mind, the present study was designed to evaluate ex vivo eNOS phosphorylation in rat aortas incubated with H2O2 and to test this hypothesis in vivo in the aortas of rats submitted to acute exercise.MethodsFor ex vivo studies, six groups of aortic tissue were formed: control, H2O2, N-acetylcysteine (NAC), LY294002, compound C, and LY294002 plus compound C. While incubation with H2O2 increased Akt, AMPK and eNOS phosphorylation, pre-incubation with NAC strongly reduced the phosphorylation of these enzymes. For in vivo studies, male Wistar rats were divided into four groups: control, cont+NAC, exercise, and exer+NAC. After a 3h swimming session, animals were decapitated and aortas were excised for biochemical and immunoblotting analysis.ResultsAcute exercise increased superoxide levels and dichlorofluorescein (DCF) concentrations, and this increase was related to phosphorylation of Akt, AMPK and eNOS. On the other hand, use of NAC reduced superoxide levels and DCF concentration. Reduced superoxide levels and DCF in the exer+NAC group were associated with decreased Akt, AMPK and eNOS phosphorylation. These results appear to be connected with vascular function because VASP phosphorylation increased in acute exercise and decreased in exer+NAC.ConclusionOur results indicate that ROS induced by acute exercise play the important role of activating eNOS, a process apparently mediated by Akt and AMPK