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Microstructural characterization and mechanical behavior analysis of 7075-T6 aluminum subjected to simulated lightning strikes

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chinese Journal of Aeronautics 2021年第12期34卷 39-50页

作者： luis henrique SANTOS Weslei Patrick Teodosio SOUSA Sara Silva Ferreira DE DAFE Pedro Americo Magalhaes JUNIOR Department of Mechanical Engineering Pontificia Universidade Catolica de Minas GeraisBelo Horizonte 30535-901Brazil

Aircrafts damages caused by lightning strikes have been known since the early days of ***,the physical effects on the aircraft structure are still being *** work seeks to evaluate the lightning strike effects in the aluminum alloy *** were submitted to lightning strike simulation in laboratory and the damages evaluated through characterization *** and profilometry tests have shown material loss to 0.272 mm depth in the damaged *** addition,it was detected the material accumulation occurrence in the damage vicinity of the *** the damage,it was found a region where metallurgical changes were *** tensile and microhardness tests results have shown reduction in the percentage elongation and hardness increasing in the material affected by *** results are corroborated by the X-Ray Diffraction(XRD)and Rietveld Method(red line)that indicated an increasing in dislocation density and micro-deformation in the material *** microscopy results have shown the presence of microcracks on the normal and cross-section surface of the samples *** Energy Dispersive X-Ray Spectroscopy(EDXS)and Electron Backscattered Diffraction Test(EBSD)found coarse intermetallic phases and precipitates compounds with dimensions greater than 1 lm in *** were responsible for nucleation of the microcracks that propagate along the material grain boundaries.

关键词： Aircraft structure characterization techniques Lightning strikes Precipitates Microcracks

Production of Invertases by Anamorphic(Aspergillus nidulans)and Teleomorphic(Emericela nidulans)Fungi under Submerged Fermentation Using Rye Flour as carbon Source

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Advances in Microbiology 2013年第5期3卷 421-429页

作者： Juliana Nunes e Oliveira alves Joao Atílio Jorge luis henrique Souza Guimaraes Department of Biology Faculty of PhylosophySciences and Letters of Ribeirao PretoUniversity of Sao PauloSao PauloBrazil

The production of invertases by anamorph (A. nidulans) and teleomorph (E. nidulans) was investigated. The best level of extracellular enzymatic production for anomorph was obtained in Khanna medium containing sucrose as carbon source, whereas for teleomorph the best production was archived using M5 medium containing inulin as carbon source. Despite this, rye flour was selected as carbon source. The extracellular enzyme production was higher for teleomorph than that observed for anomorph for all carbon sources used. The enzyme production was inhibited by the addition of fructose and glucose in the medium containing rye flour as carbon source. The best conditions to recover the higher enzymatic activity were temperature of 54℃ - 62℃ and pH of 4.8 5.6 for both enzymes determined by experimental design (ccRD). The stability of the temperatures at 40℃ and 50℃were similar for both enzymes. The invertases from the anomorph and teleomorph were activated by Mn2+, but the response of each one towards the presence of this cation was different with best activation observed for the anomorph enzyme (+80%). The extracellular enzymes were able to hydrolyze inulin, sucrose and raffinose. However, the affinity was higher for sucrose than inulin. In conclusion, the carbon source assimilation and the invertase production, as well as the enzymes properties, were different for the anomorph and teleomorph mycelia.

关键词： Invertase Fructofuranosidase Aspergillus Emericela

Enamel microabrasion: An overview of clinical and scientific considerations

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World Journal of clinical cases 2015年第1期3卷 34-41页

作者： Núbia Inocencya Pavesi Pini Daniel Sundfeld-Neto Flavio henrique Baggio Aguiar Renato Herman Sundfeld luis Roberto Marcondes Martins José Roberto Lovadino Débora alves Nunes Leite Lima Department of Restorative Dentistry Piracicaba Dental SchoolUniversity of CampinasPiracicabaSão Paulo 13414-903Brazil Department of Restorative Dentistry Araçatuba Dental SchoolSão Paulo State UniversityAraçatubaSão Paulo 16015-050Brazil

Superficial stains and irregularities of the enamelare generally what prompt patients to seek dental intervention to improve their smile. These stains or defects may be due to hypoplasia, amelogenesis imperfecta, mineralized white spots, or fluorosis, for which enamel microabrasion is primarily indicated. Enamel microabrasion involves the use of acidic and abrasive agents, such as with 37% phosphoric acid and pumice or 6% hydrochloric acid and silica, applied to the altered enamel surface with mechanical pressure from a rubber cup coupled to a rotatory mandrel of a lowrotation micromotor. If necessary, this treatment can be safely combined with bleaching for better esthetic results. Recent studies show that microabrasion is a conservative treatment when the enamel wear is minimal and clinically imperceptible. The most important factor contributing to the success of enamel microabrasion is the depth of the defect, as deeper, opaque stains, such as those resulting from hypoplasia, cannot be resolved with microabrasion, and require a restorative approach. Surface enamel alterations that result from microabrasion, such as roughness and microhardness, are easily restored by saliva. clinical studies support the efficacy and longevity of this safe and minimally invasive treatment. The present article presents the clinical and scientific aspects concerning the microabrasion technique, and discusses the indications for and effects of the treatment, including recent works describing microscopic and clinical evaluations.

关键词： Dental bleaching Enamel microabrasion Enamel surface Esthetic treatment Fluorosis Hypoplasia

Production and Partial characterization of an Extracellular Phytase Produced by Muscodor sp. under Submerged Fermentation

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Advances in Microbiology 2016年第1期6卷 23-32页

作者： Natálie Martins alves luis henrique Souza Guimarães Roberta Hilsdorf Piccoli Patrícia Gomes cardoso Department of Biology Sector of Microbiology Federal University of Lavras Lavras Brazil Department of Biology University of Sao Paulo Ribeirao Preto Brazil Department of Food Science Federal University of Lavras Lavras Brazil

In most of the raw materials of plant origin used in animal feed, a portion of the phosphorus is stored as phytic acid or phytate. Phytate is the main storage form of phosphorus in vegetables but is not readily assimilated into food at low concentrations of the enzyme phytase. In addition to making phosphorous unavailable, phytate binds divalent cations such as calcium, copper, magnesium, iron, manganese and zinc, preventing the absorption of these nutrients in the gut of the animal. Phytase promotes the hydrolysis of the phytate phosphorus-releasing molecule, thereby increasing its bioavailability in feed. Phytase is distributed in plant and animal tissues and it is synthesized by some species of bacteria and fungi. The addition of this enzyme in the diet of animals is essential to promote greater uptake of phosphorus and also contributes to a decrease in the levels of phosphorus excreted by animals, thus reducing the pollution caused by excess phosphorus in the environment. This work aimed to select a fungus that stands out in the production of phytase among 100 isolates from Brazilian caves belonging to the genera Aspergillus, Penicillium and cladosporium and 13 endophytic fungi of the aerial part of the coffee plant. For selection, the fungi were cultured in medium containing phytic acid as a sole source of phosphorus. After seven days at 25 °c, we evaluated growth and enzyme production by the presence of the phytic acid halo degradation (Enzymatic Index-EI) surrounding the colonies. Forty-seven species produced phytase, and the fungi Penicillium minioluteum (cF279) and Muscodor sp. (UBSX) showed higher degradation halos, 2.41 and 4.46, respectively. considering the Muscodor sp. as the main source of phytase, high enzymatic levels were obtained when the fungus was grown under submerged fermentation with initial pH of 5.0 using wheat bran as additional carbon source for 144 h, at 125 rpm and 30 °c. Additionally, the enzyme was stable at pH 5.0 and 40 °c, and inhi

关键词： Endophytic Fungus Muscodor sp. Phosphorus Phytase Phytic Acid

Microkernel Development for Embedded Systems

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Journal of Software Engineering and Applications 2013年第1期6卷 20-28页

作者： Rodrigo Maximiano Antunes de Almeida luis henrique de carvalho Ferreira carlos henrique Valério IESTI-Systems Engineering and Information Technology Institute UNIFEI-Federal University of Itajubá Itajubá Brazil.

This paper presents the development of a microkernel with a device driver controller for embedded systems. The implementation was done in c language aiming low cost microcontrollers. The proposed system allowed to perform soft real-time activities while keeping the drivers and the application isolated by a secure layer. The callback system proved itself extremely simple to use while still maintaining the security of the system regarding the temporal constraints.

关键词： Embedded Systems Microkernel Device Driver controller Hardware Devices callback

Effects of Biodegradable Detergents in Morphological Parameters of Liver in Two Neotropical Fish Species(Prochilodus lineatus and Astyanax altiparanae)

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Microscopy Research 2014年第2期2卷 39-49页

作者： Bruno Fiorelini Pereira Rebeca Mamede da Silva alves Anderson luis alves Jose Augusto Senhorini Rita de cassia Gimenes de Alcantara Rocha Priscilla Hakime Scalize Dimitrius Leonardo Pitol Flavio henrique caetano Universidade Estadual Paulista“Julio de Mesquita Filho”-UNESP campus de Rio claro Sao PauloBrazil EMBRAPA PalmasBrazil IcMBio/cEPTA PirassunungaBrazil Faculdade de Odontologia de Ribeirao Preto FORP/USPRibeirao PretoBrazil

Indiscriminate disposal of residues of domestic and/or industrial origin in aquatic ecosystems resulting from urban activities causes concern about their effects on the fauna. Substances absorbed by animals, such as those cited above, are metabolized by the liver, as it is the main target organ of several pollutants and also exercises basic vital functions in the organism. For this reason the liver is used as the main and most reliable biomarker in environmental studies. Thus the objective of the present study was to identify hepatic alterations resulting from exposure to water contaminated by a few commercial brands of biodegradable detergents and their effects when present together with several other contaminants found in nature. For such, a solution of 1 ppm of biodegradable detergents and water from an urban lake were tested on two widely distributed native Brazilian fish (Astyanax altiparanae and Prochilodus lineatus). Several alterations were found on the liver, including cytoplasm vacuolization, nuclear displacement, macrophage recruitment and reduced liver glycogen, showing a degenerative process in the liver of the fish, due to the action of contaminants.

关键词： Liver Fish Detergent Urban Lake Pollution

An Auto-Zero Sample-and-Hold circuit in 0.8μm cMOS

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An Auto-Zero Sample-and-Hold Circuit in 0.8μm CMOS

Optimization of the chitinase Production by Different Metarhizium anisopliae Strains under Solid-State Fermentation with Silkworm chrysalis as Substrate Using ccRD

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作者： luis henrique c.Ferreira Tales c.Pimenta Robson L.Moreno Microelectronics Group Universidade Federal de Itajuba-UNIFEI Av. BPS 1303 Itajuba-MG 37500-903 BRAZIL Microelectronics Group Universidade Federal de Itajuba-UNIFEI Av. BPS 1303 Itajuba-MG 37500-903 BRAZIL Microelectronics Group Universidade Federal de Itajuba-UNIFEI Av. BPS 1303 Itajuba-MG 37500-903 BRAZIL

＜正＞ This work describes the silicon implementation of a new sample-and-hold circuit topology. The main feature of the circuit is its auto-zero capability. The auto-zero corrects the offset voltage generated by the transistor mismatch in the differential pair and the charge injected by the NMOS switches in the sampling capacitor. The circuit was implemented in 0,8μm cMOS process from AMS. The results, initially obtained from simulations, were compared to real laboratory measurements. The comparison indicates that the measurements and the simulated results have a very close correspondence. The circuit is capable of reducing the total sample-and-hold output error to just 0.14% at a sampling rate of 250KHz.

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Advances in Microbiology 2012年第3期2卷 268-276页

作者： cynthia Barbosa Rustiguel Joao Atílio Jorge luis henrique Souza Guimaraes Department of Biology Faculdade de FilosofiaCiencias e Letras de Ribeirao PretoUniversidade de Sao PauloSao PauloBrazil

Entomopathogenic fungi, such as Metarhizium anisopliae, are able to control various insect pests. These fungi attack the integument of the host using an enzymatic complex. Among the enzymes found in this complex, chitinase is an important component. However, the relation between the chitinase production and the virulence from different M. anisopliae strains has not been analyzed. In this manuscript it is presented the chitinase production by four M. anisopliae strains with different potential of virulence in Solid-State Fermentation using silkworm chrysalis as substrate. The higher chitinase level was obtained with the strain IBcB 360 (7.14 U/g of substrate) with potential virulence of 68% on Diatrea saccharalis. The enzyme production was optimized for all strains using a factorial planning (ccRD) considering the cultivation time and medium humidity as independent variables. The maximal production of chitinase was obtained at a range from 8 to 12-days old cultures and from 45% to 62% of moisture according to the surface response plot, with high R2 value. The enzyme production by the strain IBcB 167 was increased two-folds under optimized conditions, while for the strains IBcB 360 and 425 the chitinase production was increased four-folds and nine-folds for the strain IBcB 384.

关键词： Entomopathogenic Fungus Metarhizium anisopliae chitinase Solid-State Fermentation

Alendronate disturbs femoral growth due to changes during immunolocalization of transforming growth factor-β1 and bone morphogenetic protein-2 in epiphyseal plate

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World Journal of Experimental Medicine 2020年第1期10卷 1-9页

作者： Juliana Souza Vieira Emanuelle Juliana cunha Juliana Feltrin de Souza luis henrique Koeler chaves Jessica Lakes de Souza Allan Fernando Giovanini clinical Dentistry University PositivoCuritibaPR 81280330Brazil Stomatology Department University Federal of ParanáCuritibaPR 80210-170Brazil

BAcKGROUND The epiphyseal growth plate is an important anatomical segment localized on the ends of a long *** the abovementioned atractive reasons for alendronate’s use,few data on the effect of alendronate during epiphyseal growth *** Verify the effect of alendronate on the growth epiphyseal plate,and compare its effect with the size of the femur during the double-staining of the immunolocalization of transforming growth factor-β1(TGF-β1)and bone morphogenetic protein-2(BMP2)in endochondral ossifing in specimens that have received *** Forty newborn rats were randomly divided into two groups:a control group(were given applications of 1 mg/kg physiologic saline)and a group that received Alendronate(a dose of 2.5 mg/kg).These groups were then divided into two subgroups for euthanasia in two and 12 d of *** euthanasia,the femurs were removed,and the femoral bones were measured linearly between the apex of the greater trochanter until the lower intercondylar midlle face to verify the probable bone growth between 3 and 12 d in control and alednroanto treated ***,the surgical pieces were also sent to the histopathology laboratory to produce histological *** obtained slides were stained with hematoxylin and eosin to measure each of the cartilage zones in endochondral *** other slides were immunohistochemically tested for anti-TGF-β1 and BMP-2 antibodies to investigate the immunolocalization of these proteins in the epiphyseal plaque *** On the third day,some diferences between the control group and specimens treated with alendronate were ***,we found similarities in size between the femoral bones when we compared the control group with the specimens that received *** the 12^th day,the bone size of the mice receiving the drug was significantly smaller than those of the control *** results coincide with changes in the TGF-β1 and BMP-2 *** the speci

关键词： Alendronate Bone development Epiphyseal plate Bone morphogentic protein-2 Transforming growth factor-β1