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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

Influence of the Number of Rollers on a Tapered Roller Bearing

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Journal of Mechanics Engineering and Automation 2014年第7期4卷 560-564页

作者： Alexandre da Silva Scari pedro Am6rico Almeida magalhaes junior Department of Mechanical Engineering Pontifical Catholic University of Minas Gerais Belo Horizonte 30535-901 Brazil

In roller bearings, the outer ring is usually fixed and the inner ring has the rolling motion. Concerning TRB （tapered roller bearings）, this motion generates forces that are transmitted to the outer ring by the tapered rollers. Thus, contact stresses occur and the number of rollers plays a major role with respect to the load distribution. This influence is analyzed in this study by the FEM （finite element method） with commercial code ABAQUS, where two models were evaluated： a common TRB and the same one but with fewer rollers. As an application, a manual automotive transmission was considered for the input loads.

关键词： Tapered roller bearings finite element analysis automotive manual transmission.

Piezomagnetic vibration energy harvester with an amplifier

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Theoretical & Applied Mechanics Letters 2023年第6期13卷 481-483页

作者： João pedro Norenberg americo Cunha Jr Piotr Wolszczak Grzegorz Litak Department of Mechanical Engineering São Paulo State UniversityIlha SolteiraSPBrazil Department of Applied Mathematics Rio de Janeiro State UniversityRio de JaneiroRJBrazil Department of Automation Lublin University of TechnologyLublinPoland

We study the effect of an amplification mechanism in a nonlinear vibration energy harvesting system where a ferromagnetic beam resonator is attached to the vibration source through an additional linear spring with a *** beam moves in the nonlinear double-well potential caused by interaction with two *** piezoelectric patches with electrodes attached to the electrical circuit support mechanical energy transduction into electrical *** results show that the additional spring can improve energy *** changing its stiffness,we observed various *** the point of the optimal stiffness of the additional spring,the power output is amplified a few times depending on the excitation amplitude.

关键词： Nonlinear energy harvesting Piezoelectric Displacement amplifier Bistable potential

Pleistocene Birds of Gruta da Furninha （Peniche-Portugal）： A Paleontological and Paleoenvironmental Aproach

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Journal of Environmental Science and Engineering(A) 2017年第10期6卷 502-509页

作者： Silverio Domingues Figueiredo pedro Proenga Cunha Femanda Sousa Telmo Pereira americo Rosa Polytechnic Institute of Tomar Quinta do Contador Estrada da Serra 2300-313 Tomar Portugal Portuguese Center of Geo-History and Prehistory Largo de Sao Caetano Golega 2150-265 Portugal Geosciences Center--Univ. of Coimbra Rua Silvio Lima Univ. Coimbra Coimbra 3030-790 Portugal MARE--Marine and Environmental Sciences Centre Department of Earth Sciences Coimbra University Rua Silvio LimaCoimbra 3030- 790 Portugal ICArEHB--Interdisciplinary Center for Archaeology and Evolution of Human Behaviour Human and Social Sciencies Faculty University of Algarve Campus de Gambelas 8005-139 Faro Portugal

The cave-site of Gruta da Furninha is a coastal karstic cavity. In the late 19th century, excavation of the sedimentary infill of the cave allowed the identification of two lithostratigraphic units： a Holocene one dominated by sands, containing human bones and a Neolithic industry; and a Late Pleistocene one, containing a diverse set of fossils set and Paleolithic artifacts. This study mainly focuses on taphonomic and palaeoenvironmental data concerning the Pleistocene bird bones that were collected from six layers （at 11 m and 6.7 m asl）. A main result of this study was the discovery of a left humerus fragment, with osteological features of the Alcidae family; from comparison with upper arms of distinct species of this family, it was concluded that this fossil belongs to Penguin impennis. The Pleistocene birds of the Furninha cave were also compared with the avifauna that currently occurs in the region of Peniche peninsula and a climate and environmental interpretation of the Pleistocene fossiliferous set is provided.

关键词： Birds Pleistocene marine caves Portugal.

Enzyme from Banana(Musa sp.)Extraction Procedures for Sensitive Adrenaline Biosensor Construction

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American Journal of Analytical Chemistry 2013年第6期4卷 293-300页

作者： Solange Carvalho da Silva Célio Wisniewski pedro Orival Luccas Cristiana Schmidt de magalhaes Exact Sciences Institute Federal University of Alfenas—Unifal-MGAlfenasBrazil Chemistry Institute Federal University of Alfenas—Unifal-MGAlfenasBrazil

For building a biosensor, at least two enzyme sources can be employed. The pure enzyme has features with better selectivity and low stability. Crude extract presents better stability and wrong selectivity. Thus, one intermediate condition can be feasible joining both benefits of crude extract and pure enzymes. For that result, several procedures of extraction and semi purification of polyphenol oxidase (PPO) enzyme from banana (Musa sp.) were studied. The results showed that cleaned enzymatic extracts presented higher specific activities than crude extracts (2.8 up to 5.3 fold), despite the total protein concentration diminishing from 27% up to 72%, indicating that polyphenol oxidase (PPO) enzyme was preserved in them. The biosensors with 125 AU mL-1 containing cleaned enzymatic extracts performed better by grinding or grinding plus sonication for 30 s. They were linear over the ranges of 5.9 × 10-6 mol·L-1 to 1.4 × 10-3 mol·L-1 and 7.9 × 10-8 mol·L-1 to 4.0 × 10-3 mol·L-1, respectively. The limit of Detection (LOD) was 5.9 × 10-6 mol·L-1 and 7.9 × 10-8 mol·L-1, respectively. The LOD obtained is adequate to adrenaline determination on blood and medicinal samples, and were applied in medicinal samples with satisfactory results.

关键词： Enzymatic Extract Epinephrine Biosensor Polyphenol Oxidase

Linear Stapler in Total Laryngectomy

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International Journal of Otolaryngology and Head & Neck Surgery 2014年第6期3卷 354-358页

作者： Carolina Durao Sofia Decq Motta Ana Hebe Ricardo Pacheco pedro Montalvao Miguel magalhaes Otolaryngology Department Hospital Prof.Doutor Fernando FonsecaAmadoraPortugal Otolaryngology Department Portuguese Oncology Institute of LisbonFrancisco GentilPortugal

Introduction: Stapler application for pharyngeal closure after total laryngectomy allows rapid watertight closure. We intend to report the experience of the Portuguese Oncology Institute of Lisbon, Francisco Gentil (IPOLFG). Material and Methods: Retrospective study of patients submitted to total laryngectomy using linear stapler device treated in IPOLFG from 2005 to 2010. Results: 108 patients were studied. The majority of patients were male, aged from 60 to 69 years old, and had smoking and alcohol habits. The average length of hospital stay was 13.1 days. Post-operative complications occurred as follows: wound infection in 6.5%, cervical hematoma in 4.6% and pharyngocutaneous fistula in 11.1% of cases. Conclusions: The mechanical suture of the pharynx in total laryngectomy is a simple and quick method. It does not increase the incidence of post-operative complications. It seems to be a very safe method, as long as its limits regarding the location and extent of tumour are respected.

关键词： Pharyngeal Closure Total Laryngectomy Linear Stapler

The road to opportunities： landscape change promotes body-size divergence in a highly mobile species

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Current Zoology 2016年第1期62卷 7-14页

作者： Carlos CAMACHO pedro SAEZ Sonia SANCHEZ Sebastian PALACIOS Carlos MOLINA Jaime POTTI Department of Evolutionary Ecology Estacion Biologica de Donana--CSIC Av. Americo Vespucio 41092 SevilleSpain Department of Environmental Biology and Public Health. University of Huelva. Av. Andalucia 21071 HuelvaSpain Department of Conservation Biology Estacion Biologica de Donana--CSlC Av. Americo Vespucio 41092Seville Spain Sociedad Espafiola de Ornitologia. Centro Ornitologico Francisco Bernis. Paseo Marismeno sn 21750 Huelva Spain

Landscape change provides a suitable framework for investigating population-level responses to novel ecological pressures. However, relatively little attention has been paid to examine the poten- tial influence of landscape change on the geographic scale of population differentiation. Here, we tested for morphological differentiation of red-necked nightjars Caprimulgus ruficollis breeding in a managed property and a natural reserve situated less than 10 km apart. At both sites, we also esti- mated site fidelity over 5 years and quantified the potential foraging opportunities for nightjars. Breeding birds in the managed habitat were significantly larger in size--as indexed by keel length--than those in the natural one. However, there were no significant differences in wing or tail length. Immigration from neighboring areas was almost negligible and, furthermore, no individual （out of 1130 captures overall） exchanged habitats between years, indicating strong site fidelity. Food supply for nightjars was equally abundant in both habitats, but the availability of foraging sites was remarkably higher in the managed property. As a result, nightjars--particularly fledg- lings-in the latter habitat benefited from increased foraging opportunities in relation to those in the natural site. It seems likely that the fine-scale variation in nightjar morphology reflects a pheno- typic response to unequal local conditions, since non-random dispersal or differential mortality had been determined not to be influential. High site fidelity appears to contribute to the mainten- ance of body-size differences between the two habitats. Results from this nightjar population high- light the potential of human-induced landscape change to promote population-level responses at exceedingly small geographic scales.

关键词： human-induced environmental change morphology phenotypic divergence philopatry population differentiation.

FeedEfficiencyService: An architecture for the comparison of data from multiple studies related to dairy cattle feed efficiency indices

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Information Processing in Agriculture 2022年第3期9卷 378-396页

作者： Heitor Magaldi Linhares Regina Braga Wagner Antonio Arbex Mariana magalhaes Campos Fernanda Campos Jose Maria N.David Victor Stroele Programa de Pos-Graduacao em Ciencia da Computacao Universidade Federal de Juiz de ForaCampus UniversitarioRua JoseLourenco Kelmers/n-Sao PedroJuiz de ForaMinas Gerais 36036-900Brasil Brazilian Agricultural Research Corporation-Embrapa Av.Eugenio do Nascimento610-AeroportoJuiz de Fora-MGMinas Gerais 36038-330Brasil

The increased demand for food worldwide,the reduced land availability for livestock pro-duction,the increasing cost of animal feed and the need for mitigating livestock-related greenhouse gas emissions have driven the search for animal feeding systems that proves more *** tackle this problem,we propose the use of computational support to help researchers compare data on feed efficiency,therefore improving economic and environ-mental *** a solution,we present an integrative architecture capable of combining heterogeneous data from multiple experiments related to dairy cattle feed efficiency *** proposed architecture,called FeedEfficiencyService,classifies animals according to feed efficiency indices and allows visualizations through ontologies and inference *** results obtained from a case study with researchers from the Brazilian Agri-cultural Research Corporation–Dairy Cattle(EMBRAPA)demonstrate that this architecture is a supporting tool in their daily work *** researchers highlighted the importance of the proposed architecture as it allows analyzing animal data,comparing experiments,having reliable data analyses,and standardizing and organizing data from *** novelty of our approach is the use of ontologies and inference engines to enable the discovery of new knowledge and new relationships between data from feed efficiency-related *** store such data,relationships,and analyses of results in an inte-grated *** solution ensures unified access to the processing history and data from diverse experiments,including those conducted at external research centers.

关键词： Dairy Cattle

Total Knee Arthroplasty:Patellar Replacement’s Influence in Patient Quality of Life Postoperatively

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Open Journal of Orthopedics 2017年第8期7卷 228-234页

作者： Carlos Roberto Schwartsmann Gabriel Severo da Silva Ivan Fadanelli Simionato Flavia magalhaes Nunes Henrique Lammerhirt Joao pedro Farina Brunelli Leandro de Freitas Spinelli Federal University of Medical Sciences Porto AlegreBrazil Department of Orthopedics and Traumatology Irmandade Santa Casa de Misericordia de Porto AlegrePorto AlegreBrazil

Objective: To study the influence of patellar resurfacing on quality of life under a standardised score. The chosen score was the Knee Society Score (KSS), which considers range of motion, pain, contractors, alignment and stability. Methods: Retrospective review of 60 patients submitted to total knee arthroplasty (TKA) was divided into two groups: with patellar resurfacing (PR) and without patellar resurfacing (NPR). We reviewed data from these patients containing the KSS, which are routinely used in our service. Data were analysed from 2013 to 2014, with a minimal patient follow-up of 18 months. Results: There were no unsatisfactory scores in our study. Total scores (KSS) were similar between the groups (mean KSS: PR = 88.36 ± 9.64;NPR = 84.26 ± 9.44 [p = 0.1]). While stratifying into groups (poor, fair, good, excellent), we found excellent results in 84.8% of PR versus 59.3% NPR (p = 0.056). These data did not reach statistical significance and can therefore be considered a coincidental result. Conclusion: Although these results did not show statistical significance (p = 0.056), patellar resurfacing patients tend to get more “excellent” results after 18 months of follow-up in quality of life when evaluated by KSS. Perhaps a larger amount of patients would suffice to acquire statistical significance in a future study.

关键词： Knee Arthroplasty Patella Joint Instability Quality of Life

A New Era in the Adjuvant Treatment of Pancreatic Adenocarcinoma

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Journal of Cancer Therapy 2019年第12期10卷 915-919页

作者： Manuela Machado Maria Leitao Mário Fontes e Sousa magalhaes e Helena Oncologia Medica IPO PortoPortoPortugal Oncologia Medica Centro Hospitalar Lisboa Ocidental(CHLO)LisboaPortugal Oncologia Medica Unidade Local de Saude de MatosinhosHospital Pedro HispanoMatosinhosPortugal

Pancreatic adenocarcinoma is currently a major public health problem, being the 7th cause of death worldwide. Incidence is increasing and unfortunately nowadays the incidence is almost overlapping to mortality. The cornerstone of curative treatment is still surgery, but adjuvant treatment is critical to decreasing the risk of recurrence.

关键词： Pancreatic Adenocarcinoma Adjuvant Chemotherapy Positive Clinical Trials