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Failure in Fuel Injector Nozzles Used in Diesel Engines

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Journal of Mechanics Engineering and Automation 2015年第4期5卷 237-240页

作者： Jose Costa de Macedo Neto Marina Anunciacao Brito de Oliveira Eduardo Rafael Barreda del Campo ricardo Wilson aguiar Da Cruz Nayra Reis do Nascimento Joao Evangelista Neto Department of Materials Engineering School of Engineering Amazonas State University Manaus 69065-020 Brazil Department of Mechanical Engineering School of Engineering Amazonas State University Manaus 69065-020 Brazil Department of Materials Engineering and Bioprocess Faculty of Chemical Engineering University of Campinas Sao Paulo13083-852 Brazil Department of Electrical Engineering Faculty of Technology University Federal of Amazonas Manaus 69077-000 Brazil

This paper aims to conduct a study of the problems associated with the wear of the needles and fuel injection nozzles utilized in diesel engines. The wear found on the needles is mainly associated to impurities in the fuel oil and microcavitation occurred due to high pressure in the phase of the air compression for combustion of the combustible fluid. These pressures associated with the temperature and the fluid velocity results in the occurrence of vaporization, which releases shock waves that cause damage to the affected surface. The impurities solid particles from the fuel oil cause problems inside the nozzles as obstruction of the holes and wear on the needle tip and nozzle seat surface. These failures affect in the atomization of the fuel, since the deterioration of the internal passages of the nozzles interferes in the spray formation and in the end passage of the fluid. For the execution of this study it will be used digital microscopic analysis in specimens that suffered damage, in order to investigate the effects of fuel property, and the temperature conditions and pressure in the formation of the wear on the needles and injector nozzle.

关键词： Fuel injector nozzle injector needles wear.

Main Technical Differences in the Processing of Broilers： A Comparison between Slaughterhouses in Brazil and UK

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Journal of Agricultural Science and Technology(A) 2016年第2期6卷 136-142页

作者： ricardo Lacava Bailone Roberto de Oliveira Roca Luis de aguiar Moira Harris Universidade Estadual Paulista Julio de Mesquita Filho (UNESP)-Botucatu SP and Harper Adams University Newport United Kingdom/Federal Inspection Agent of the Brazilian Ministry of Agriculture Livestock and Supply Sao Paulo 13.565-580 Brazil Department of Animal Health Veterinary Public Health and Food Safety Universidade Estadual Paulista Julio de Mesquita Filho (UNESP)-Botucatu Sao P aulo 18.610-307 Brazil Food Marketing and Food Security Department of Food Science Harper Adams University Newport Shropshire TF10 8NB United Kingdom Animal Science Department of Animal Production and Welfare Harper Adams University Newport Shropshire TF10 8NB United Kingdom

Rapid technological advances in chicken processing in plants around the world have meant that different techniques are being employed regarding the slaughter＇s flow process. This paper aimed to compare and contrast systems and practices in two large slaughterhouses--one in UK and the other in Brazil. Annotated observations were made during inspection visits to chicken slaughterhouses in the two countries between 2014 and 2016. Whilst there were similarities in the two systems, there are also clear differences. The Brazilian case is evidently adapted for a more tropical condition, rather than the temperate one in UK. The handling practices of birds used during transportation, waiting, stunning as well as pre-cooling differ in techniques employed and consequently likely their efficiencies. In UK, the practices are more geared towards water and energy saving. The difference in market conditions and the length of the respective supply chains also determine the type of primary packaging used in final products. Both countries adhere to similar rulings applied to slaughterhouses. However, in the Brazilian case, it tended to comply with mainly external market demands. In conclusion, managers in the Brazilian poultry system could consider looking into adopting some of the practices used in UK, such as cage/crate dimension which reduce bird＇s lesions and bruises; the use of stunning by modified atmosphere and pre-cooling for resource efficiency reasons and improvement in animal welfare. Finally, when distances between sites of production and consumption are great such as in Brazil, the use of modified atmosphere technology could be also further explored to ensure better quality of the final product.

关键词： Abattoir chicken food technology food security poultry.

Determination of the Antiretroviral Drug Zidovudine in Diluted Alkaline Electrolyte by Adsorptive Stripping Voltammetry at the Mercury Film Electrode

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American Journal of Analytical Chemistry 2011年第2期2卷 223-234页

作者： Arnaldo aguiar Castro ricardo Queiroz Aucélio Nicolás Adrián Rey Eliane Monsores Miguel Percio Augusto Mardini Farias 不详

This paper describes a stripping method for the determination of zidovudine at the submicromolar concentration levels. This method is based on the controlled adsorptive accumulation of zidovudine at the thin-film mercury electrode, followed by a linear-sweep stripping voltammetry measurement of the surface species. Optimal experimental conditions include a NaOH solution of 2.0 × 10–3 mol●L–1 (sup-porting electrolyte), an accumulation potential of –0.30 V and a scan rate of 100 mV?s–1. The response of zidovudine is linear over the concentration range 0.01 - 0.08 ppm. After an accumulation time of 5 minutes, the detection limit was found to be 0.67 ppb (2.5 × 10–9 mol●L–1). More convenient methods to measure zidovudine concentration in the presence of the didanosine, acyclovir, nevirapine, lamivudine, and efavirenz, were also investigated. The presence of zidovudine together with ATP or ssDNA demonstrates the utility of this method.

关键词： Zidovudine Determination Antiviral Drugs Ssdna Thin-Film Mercury Electrode Stripping Voltammetry

The Use of Erythropoietin in Liver Regeneration in Pigs after Partial Hepatectomy

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Surgical Science 2015年第11期6卷 518-526页

作者： Henrique de aguiar Wiederkehr Caroline Aragao de Carvalho Julio Cesar Wiederkehr ricardo Ribeiro Gama Eros Luiz de Sousa Teresa Cristina Cavalcanti Taíse Fuchs Barbara de aguiar Wiederkehr Lucas Mansano Sarquis Faculdade Evangelica do Paraná CuritibaParanáBrazil Department of Surgery Federal University of ParanáCuritibaParanáBrazil Department of Experimental Surgery Faculdade Evangélica do ParanáCuritibaParanáBrazil Department of Veterinary Medicine Faculdade Evangélica do ParanáCuritibaParanáBrazil Department of Pathology Federal University of ParanáCuritibaParanáBrazil Department of Veterinary Anesthesiology Faculdade Evangélica do ParanáCuritibaParanáBrazil

A partial hepatectomy is a surgical procedure performed during the living-donor liver transplantation and sometimes the only option for patients with hepatocarcinoma. However the remnant liver after the hepatectomy is still a major concern. Therefore, the process of liver regeneration has been a constant theme of study in order to optimize this process. Erythropoietin, a hormone produced by the kidney and involved in protecting organs like heart, liver and kidney itself against injuries can be one of these factors that could accelerate the liver regeneration. This study aims to observe if erythropoietin can accelerate the process of liver regeneration after partial hepatectomy in pigs. Methods: 8 pigs were classified into 2 groups of 4 pigs each: the control group and the test group. The animals in the first group underwent an application of saline solution subcutaneous on the day before the hepatectomy. Instead of saline solution, the test groups received a subcutaneous injection of 200 UI/lg of recombinant erythropoietin also on the day before the surgical procedure. After 7 days since the hepatectomy, in each animal the liver was biopsied in two regions, one next to the hepatectomy section and other far from it. The liver regeneration was analyzed using Ki-67. Results: Pigs from control group presented the following results: Control pig I: 30% of regeneration in the hepatectomy section and 10% in the region far from it;control pig II 24% and 4%;control pig III 27% and 7%. The test group presented no significant liver regeneration since Ki-67 could not identify cell proliferation in neither the biopsied areas. Conclusion: Since the number of pigs was not statistically significant, we could not conclude any further hypothesis. We strong believe that enhancing the number of pigs and testing different doses, we will be able to reach further conclusions.

关键词： Liver Regeneration Partial Hepatectomy Erythropoietin Pigs

The Importance of the Three-Dimensional Image in the Early Diagnosis of Cementoblastoma

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Open Journal of Radiology 2012年第1期2卷 10-13页

作者： Tania Mara Pimenta Amaral Claudia Silami de Magalhaes Allyson Nogueira ricardo Alves Mesquita Joao Batista de Freitas Maria Cassia Ferreira aguiar Department of Oral Pathology and Surgery School of Dentistry Universidade Federal de Minas Gerais Belo Horizonte Brazil Department of Restorative Dentistry School of Dentistry Universidade Federal de Minas Gerais Belo Horizonte Brazil

The cementoblastoma is a very rare odontogenic neoplasm characterised by the formation of cementum-like tissue in connection with the root of a tooth. An 18-year-old boy was referred to the Clinic of Oral Pathology of the School of Dentistry, Universidade Federal de Minas Gerais, Brazil, complaining of an irradiating, itching pain from the region of the lower right first molar. He reported that the symptoms began three months prior, with a gradual increase in intensity during this period. The pain episodes were of short duration, with characteristics of toothache originating from the pulp. Upon intra-oral clinical examination, an open bite and slight increase in volume at the buccal alveolar region of the lower right first molar was observed. He also reported palpation and percussion pain symptoms in this region. Electrical, heat and cold pulp vitality tests were performed, and the tooth was vital. Periapical and panoramic radiographs showed radiolucent images with diffuse, poorly defined borders at the mesial root periapex extending to the interradicular region suggesting an inflammatory periapical lesion. In this early presentation, the three-dimensional image was fundamental to the final diagnosis of cementoblastoma.

关键词： Cementoblastoma Cone Beam CT Dental Radiography

What Do Seedlings Like? The Relationship between Seedling Richness and Abundance with Abiotic Factors

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Agricultural Sciences 2023年第6期14卷 767-774页

作者： Johnatan Jair de Paula Marchiori Vinicius de Souza Oliveira Eduarda Carriço Ana Clara Bayer Bernabé Anderson Mathias Holtz Ronilda Lana aguiar Ana Beatriz Mamedes Piffer Gilcéa Teixeira Fontana Boone ricardo Amaro de Sales Lusiane de Sousa Ferreira Department of Environmental Sciences/Phytotechnics Department Federal University Rural of Rio de Janeiro-Seropédica Rio de Janeiro Brazil Center for Agricultural Sciences and Engineering Federal University of Espírito Santo Alegre Espírito Santo Brazil Laboratory of Entomology and Acarology Federal Institute of Espírito Santo Campus Itapina Colatina Espírito Santo Brazil Agriculture Department State University Paulista “Júlio de Mesquita Filho” Botucatu S&#227o Paulo Brazil

Natural regeneration is the interaction of natural processes to restore the forest ecosystem. Its dynamics are influenced by the intensity and extent of a series of abiotic and biotic factors, which may be intrinsic or extrinsic. Knowing the importance of establishing natural regeneration within forest ecosystems, this work aimed to evaluate whether litter depth and trail distance influenced seedling abundance and richness in a forest fragment undergoing natural restoration. The hypothesis tested in this research was that abiotic factors influence the natural regeneration of this forest since they are factors that are directly linked to seed germination and seedling establishment. 30 plots of 1 m2 were randomly analyzed within the forest located on the brown trail. A millimeter ruler was used to diagnose the litter depth and a measuring tape to measure the distance from the plot to the edge. In each plot the seedlings were morpho-specified and each morphospecies had the number of individuals counted. Linear regression tests were performed to assess the relationships between species richness and trail distance and litter depth. The same was done for species abundance. All results showed that there is no relationship pattern between any of the variables. Other factors also influence the regeneration of a forest, such as luminosity and seed bank. Furthermore, litter depth is related to the successional stage of the forest. It was concluded that the abiotic factors tested do not influence the regeneration of the study area.

关键词： Abiotic Factors Natural Regeneration Forest Ecosystem

Normative data for TM electrocochleography measures

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Journal of Otology 2017年第2期12卷 68-73页

作者： Signe Schuster Grasel Roberto Miquelino de Oliveira Beck ricardo Silva Chiabai Loureiro Amanda Costa Rossi Edigar Rezende de Almeida John Ferraro University of Sao Paulo School of Medicine Dr.Eneas de Carvalho Aguiar255sala 6173Cerqueira CesarSao PauloSP CEP 05403-000Brazil University of Kansas Medical Center Kansas CityKS 66160USA

Objective: Establish normative data for tympanic electrocochleography(TM ECoch G) parameters in normal hearing adults without Meniere's disease's(MD) symptoms. Describe TM ECoch G variables that help to distinguish normal from MD *** and methods: We enrolled 100 subjects(N =200 ears), 59 females, aged between 19 and 71 years from 09/2010 to 04/2014. Inclusion criteria: normal otomicroscopy, hearing thresholds≤25 dB nHL from 250 to 4000 Hz, normal tympanogram, no symptoms of MD according to the AAO-HNS 1995 criteria and Gibson's score <7. We excluded subjects with dizziness, aural fullness or other symptoms of endolymphatic hydrops. The following parameters were analyzed: SP/AP amplitude ratio, SP/AP area ratio and the difference between AP latency with rarefaction and condensation ***: There was no significant difference between right and left ears(Intraclass correlation coefficient < 0.6). SP/AP amplitude ratio varied between 0.084 and 0.356 and SP/AP area ratio between 0.837 and 1.671(percentiles 5 and 95). The AP latency difference to rarefaction and condensation clicks was between 0.0 and 0.333 ***: Normative data for TM ECoch G parameters were established in 100 normal hearing subjects without MD. These data can be used to distinguish normal from pathological findings and in follow-up of MD patients.

关键词： Electrocochleography Meniere disease Hearing Dizziness Tinnitus