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β-defensins and the epididymis： contrasting influences of prenatal, postnatal, and adult scenarios

Asian Journal of Andrology 2016年第2期18卷 323-328,J0008页

作者： Camilla M Ribeiro erick jr silva Barry T Hinton Maria Christina W Avellar Section of Experime.ntaI.Endocrinology Department of Pharmacology Universidade Federal de Sao Paulo - Escola Paulista de Medicina Sao Paulo Brazil Department of Cell Biology University of Virginia School of Medicine Charlottesville Virginia USA Present address: Department of Pharmacology Institute Of Biosciences of BotucatuUniversidade Estadual Paulista 'Julio de Mesquita Filho' Botucatu Sao Paulo 186).8-970 Brazil.

β-defensins are components of host defense, with antimicrobial and pleiotropic immuno-modulatory properties. Research over the last 15 years has demonstrated abundant expression of a variety of β-defensins in the postnatal epididymis of different species. A gradient of region- and cell-specific expression of these proteins is observed in the epithelium of the postnatal epididymis. Their secretion into the luminal fluid and binding to spermatozoa as they travel along the epididymis has suggested their involvement in reproduction-specific tasks. Therefore, continuous attention has been given to various β-defensins for their role in sperm function and fertility. Although β-defensins are largely dependent on androgens, the underlying mechanisms regulating their expression and function in the epididymis are not well understood. Recent investigation has pointed out to a new and interesting scenario where β-defensins emerge with a different expression pattern in the Wolffian duct, the embryonic precursor of the epididymis, as opposed to the adult epididymis, thereby redefining the concept concerning the multifunctional roles of β-defensins in the developing epididymis. In this review, we summarize some current views of β-defensins in the epididymis highlighting our most recent data and speculations on their role in the developing epididymis during the prenatal-to-postnatal transition, bringing attention to the many unanswered questions in this research area that may contribute to a better understanding of epididymal biology and male fertility.

关键词： androgens embryogenesis epididymis organogenesis β-defensins

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Transesterification of sunflower oil in microchannels with circular obstructions

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Chinese Journal of Chemical Engineering 2018年第4期26卷 852-863页

作者： Harrson S.Santana Joao L.silva jr Deborah S.Tortola Osvaldir P.Taranto School of Chemical Engineering University of Campinas13083-852 CampinasSPBrazil Federal Institute of Education Science and Technology of South of Minas Gerais-IFSULDEMINAS37560-260 Poaso AlegreMGBrazil

The present paper studied numerical and experimentally the transesterification reaction between sunflower oil and ethanol with NaO H catalyst in microchannels with circular obstructions. The micromixer design influence on fluid mixing and oil conversion was investigated for a range of operating conditions: Reynolds number(Re = 0.1–100),Temperature(25–75 °C), ethanol/oil molar ratio(6-12), and catalyst concentration(0.75 wt%–1.25 wt%), using three microchannel configurations(Length = 35 mm; Width = 1500 μm; Height = 200 μm): T-shape – channel without obstructions; MCO – channel with 3 obstructions ensemble – equally disposed over longitudinal length;MWO – channel with 7 obstructions ensemble. The MCO micromixer was based on literature work, and the MWO is a totally new micromixer design. Experimental tests were conducted in similar conditions in microreactors using these micromixers(Length = 411 mm) made of polydimethylsiloxane. The MCO configuration presented the highest performance(mixing index of 0.80 at Re = 100), oil conversion of 81.13% at 75 °C, molar ratio of 9 and catalyst concentration of 1%. Experimental results showed high conversions for MCO and MWO configurations(99.99%) at 50 °C, molar ratio of 9 and catalyst concentration of 1%, with a residence time of 12 s.

关键词： Biodiesel Sunflower oil-ethanol Transesterification reaction Circular obstructions Microreactor Numerical simulation

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Appropriate search techniques to estimate Weibull function parameters in a Pinus ***

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Journal of Forestry Research 2021年第6期32卷 2423-2435页

作者： Lais Almeida Araujo Rafael Menali Oliveira Mario Dobner jr Carolina Souza Jarochinskie silva Lucas Rezende Gomide Department of Forest Sciences Federal University of LavrasLavrasMinas GeraisBrazil Department of Agriculture Biodiversity and ForestsFederal University of Santa CatarinaCuritibanosSanta CatarinaBrazil

The Weibull function,a continuous probability distribution,is widely used for diameter distribution modelling,in which parameter estimation performance is affected by stand attributes and fitting *** Weibull cumulative distribution function is nonlinear,and classical fitting methods may provide a not optimal *** the use of artificial intelligence by metaheuristics is reasonable for this optimisation ***,aimed and compared(1)the metaheuristics genetic algorithm and simulated annealing performance over the moment and percentile methods;(2)the hybrid strategy merging the metaheuristics tested and the percentile method and,(3)the metaheuristics fitness functions under basal area and density errors.A long-term experiment in a Pinus taeda stand subjected to crown thinning was *** to our findings,all methods have a similar performance,independent of the thinning regimes and *** pattern of the estimated parameters tends to be acceptable,as b increases over time and c increases after ***,our findings suggest that methods based on metaheuristics have a higher precision than classical methods for estimating Weibull *** to the classification test,the methods that involved simulated annealing stood *** hybrid method involving this metaheuristic also stood out,with accurate *** methods showed the poorest performance,and we therefore suggest the use of simulated annealing due to its faster processing time and high-quality solution.

关键词： Forest management Diameters distribution Weibull function Genetic algorithm Simulated annealing

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A phased approach to enable hybrid simulation of complex structures

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Earthquake Engineering and Engineering Vibration 2014年第S1期13卷 63-77页

作者： Billie F.Spencer jr. Chia-Ming Chang Thomas M.Frankie Daniel A.Kuchma Pedro F.silva Adel E.Abdelnaby Department of Civil Engineering University of Illinois at Urbana-Champaign Nathan M.& Anne M.Newmark Endowed Chair Earthquake Engineering Research &Test Center Guangzhou University Associate Professor Wiss JanneyElstner AssociatesInc. Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign Department of Civil and Environmental Engineering George Washington University Department of Civil Engineering University of Memphis Assistant Professor

Hybrid simulation has been shown to be a cost-effective approach for assessing the seismic performance of structures. In hybrid simulation,critical parts of a structure are physically tested,while the remaining portions of the system are concurrently simulated computationally,typically using a finite element model. This combination is realized through a numerical time-integration scheme,which allows for investigation of full system-level responses of a structure in a cost-effective manner. However,conducting hybrid simulation of complex structures within large-scale testing facilities presents significant challenges. For example,the chosen modeling scheme may create numerical inaccuracies or even result in unstable simulations; the displacement and force capacity of the experimental system can be exceeded; and a hybrid test may be terminated due to poor communication between modules(e.g.,loading controllers,data acquisition systems,simulation coordinator). These problems can cause the simulation to stop suddenly,and in some cases can even result in damage to the experimental specimens; the end result can be failure of the entire experiment. This study proposes a phased approach to hybrid simulation that can validate all of the hybrid simulation components and ensure the integrity largescale hybrid simulation. In this approach,a series of hybrid simulations employing numerical components and small-scale experimental components are examined to establish this preparedness for the large-scale experiment. This validation program is incorporated into an existing,mature hybrid simulation framework,which is currently utilized in the Multi-Axial Full-Scale Sub-Structuring Testing and Simulation(MUST-SIM) facility of the George E. Brown Network for Earthquake Engineering Simulation(NEES) equipment site at the University of Illinois at Urbana-Champaign. A hybrid simulation of a four-span curved bridge is presented as an example,in which three piers are experimentally controlle

关键词： hybrid simulation seismic performance evaluation phased approach curved bridge MUST-SIM facility

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3D printed millireactors for process intensification

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Chinese Journal of Chemical Engineering 2020年第1期28卷 180-190页

作者： Harrson S.Santana Alan C.Rodrigues Mariana G.M.Lopes Felipe N.Russo Joao L.silva jr Osvaldir P.Taranto School of Chemical Engineering University of CampinasBrazil Federal Institute of Education Science and Technology of South of Minas GeraisBrazil

The scope of the present research aims at demonstrating the 3D printing use in the manufacturing of microchannels for chemical process applications. A comparison among digital model processing applications for 3D print(slicers) and a print layer thickness analysis were performed. The 3D print fidelity was verified in several devices, including the microchannels’ printing with and without micromixer zones. In order to highlight the 3D print potential in Chemical Engineering, the biodiesel synthesis was also carried out in a millireactor manufactured by 3D printing. The millireactor operated under laminar flow regime with a total flow rate of 75.25 ml·min^-1(increment of about 130 times over traditional microdevices used for biodiesel production).The printed millireactor provided a maximum yield of Ethyl Esters of 73.51% at 40 ℃, ethanol:oil molar ratio of7 and catalyst concentration of 1.25 wt% and residence time about 10 s. As a result of flow rate increment attained in the millireactor, the number of required units for scaling-up the chemical processes is reduced. Using the approach described in the present research, anyone could produce their own millireactor for chemical process in a simple way with the aid of a 3D printer.

关键词： Process intensification 3D printer Millireactors Micromixers Microdevices Biodiesel

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