检索结果-南通市图书馆

Horizontally Solidified Al-3 wt%Cu-(0.5 wt%Mg)Alloys:Tailoring Thermal Parameters,Microstructure,Microhardness,and Corrosion Behavior

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English letters) 2019年第6期32卷 695-709页

作者： Andre barros Clarissa Cruz Adrina P.Silva Noe Cheung Amauri Garcia Otavio Rocha Antonio moreira Institute of Technology Federal University of Para-UFPABelemPA 66075-110Brazil Federal Institute of Education Science and Technology of Para-IFPABelemPA 66093-020Brazil Department of Manufacturing and Materials Engineering University of Campinas-UNICAMPCampinasSP 13083-860Brazil

In the present experimental investigation,Al–3 wt%Cu and Al–3 wt%Cu–0.5 wt%Mg alloys castings are produced by a horizontal solidification technique with a view to examining the interrelationship among growth rate(GR),cooling rate(CR),secondary dendrite arm spacing(λ2),Vickers microhardness(HV),and corrosion behavior in a 0.5 M NaCl *** intermetallic phases of the as-solidified microstructures,that is,h-Al2Cu,S–Al2CuMg,and x-Al7Cu2 Fe,are subjected to a comprehensive characterization by using calculations provided by computational thermodynamics software,optical microscopy,and scanning electron microscopy/energy-dispersive ***,electrochemical impedance spectroscopy and potentiodynamic polarization tests have been applied to analyze the corrosion performance of samples of both alloys ***–Petch-type equations are proposed to represent the HV dependence onλ*** is shown that the addition of Mg to the Al–Cu alloy has led to a considerable increase in HV;however,the Al–Cu binary alloy is shown to have lower corrosion current density(icorr)as well as higher polarization resistance as compared to the corresponding results of the Al–Cu–Mg ternary alloy.

关键词： Aluminum alloys Solidification Dendritic microstructure Intermetallic phases Microhardness Corrosion resistance

What a few hairs can tell us about the resource use of giant armadillos

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Integrative Zoology 2023年第1期18卷 129-142页

作者： Marcelo MAGIOlI Nina ATTIAS Gabriel MASSOCATO Danilo KlUYBER Marcelo Zacharias moreira Katia Maria Paschoaletto Micchi de barros FERRAZ Adriano Garcia CHIAREllO Arnaud l.J.DESBIEZ Instituto Pró-Carnívoros AtibaiaSão PauloBrazil Centro Nacional de Pesquisa e Conservação de Mamíferos Carnívoros(CENAP) Instituto Chico Mendes de Conservação da Biodiversidade(ICMBio)AtibaiaSão PauloBrazil Instituto de Conservação de Animais Silvestres(ICAS) Campo GrandeMato Grosso do SulBrazil Instituto de Pesquisas Ecológicas Organização Não GovernamentalNazaréPaulistaSão PauloBrazil Houston Zoo HoustonTexasUSA Naples Zoo at Caribbean Gardens NaplesFloridaUSA laboratório de Ecologia Isotópica Centro de Energia Nuclear na AgriculturaUniversidade de São PauloPiracicabaSão PauloBrazil laboratório de Ecologia Manejo e Conservação de Fauna Silvestre(LEMaC)Departamento de Ciências FlorestaisEscola Superior de Agricultura“Luiz de Queiroz”(ESALQ)Universidade de São Paulo(USP)PiracicabaSão PauloBrazil Departamento de Biologia Faculdade de FilosofiaCiências e LetrasUniversidade de São Paulo(USP)Ribeirão PretoSão PauloBrazil RZSS-Royal Zoological Society of Scotland(RZSS) MurrayfieldEdinburghUK

Understanding of resource requirements of vulnerable species is key for conservation ***,we used sta-ble carbon(δ13C)and nitrogen isotopes(δ15N)of hair from giant armadillos(Priodontes maximus)to understand individual resource *** collected hair from 19 giant armadillos analyzing 34 samples from the Brazilian Pan-tanal and compared the resource use between sexes and age *** also assessed the relationship of isotopic values with individuals’body mass and the habitat type *** observed a wide variation in resource use by giant armadillos,showing that individuals consume prey that feeds on distinct resources and occupies different habitat types,indicating that there is individual variation in foraging *** giant armadillos presented a mixed diet(C3/C4 resources,forests/open areas),but a quarter of individuals had strictly C4 diets(open areas).Males are more prone to forage on C4 resources,presenting an isotopic niche 2.6-times larger than that of *** presented diets more associated with habitats with high arboreal cover(C3 resources,forests),while adults foraged more in open areas(C4 resources).This result is mirrored by the positive relationship betweenδ13C values and body mass,suggesting that larger giant armadillos tend to feed more in open *** observed thatδ13C values decreased as individuals increased the use of habitats with high arboreal *** stress the importance of con-serving the natural mosaic in the Pantanal landscape for the species persistence,given that giant armadillos require all habitat types to fulﬁll their dietary,spatial,and developmental needs.

关键词： diet ontogenetic changes resource partitioning stable isotopes telemetry

Sleep in children with eosinophilic esophagitis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Pediatrics 2021年第2期17卷 111-114页

作者： Isabela A Ishikura Gustavo moreira SergioTufik Monica l.Andersen Department of Psychobiology Universidade Federal de Sao Paulo(UNIFESP)Napoleao de Barros925 Vila ClementinoSao PauloSP 04024-002Brazil

Eosinophilic esophagitis(EoE)is a chronic immune-and antigen-mediated disease caused by infiltration of eosino-phils in esophagus tissue,which leads to morphological and functional abnormalities at this site[1].This disease was discovered in 1995 by Kelly et al.[2];since then,it has become increasingly recognized and discussed by research-ers[2,3].EoE affects children and adults and is three times more prevalent in males than in *** to a recent systematic review,there are 19.1 cases of EoE per 100,000 children/year,with a higher frequency in Western countries[4].

关键词： esophagitis al. esophagus

No evidence of HPV DNA in esophageal squamous cell carcinoma in a population of Southern Brazil

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2013年第39期19卷 6598-6603页

作者： luís Carlos moreira Antunes Joo Carlos Prolla Antonio de barros lopes Marta Pires da Rocha Renato Borges Fagundes Programa de Pós-Graduao: Ciências em Gastroenterologia e Hepatologia - Universidade Federal do Rio Grande do Sul Porto AlegreRio Grande do Sul 90035-003Brasil Hospital Universitário de Santa Maria - Universidade Federal de Santa Maria Santa MariaRio Grande do Sul 97119-900Brasil Departamento de Clínica Médica - Universidade Federal de Santa Maria Santa MariaRio Grande do Sul 97119-900Brasil

AIM:To investigate the association between human papillomavirus(HPV)and esophageal squamous cell carcinoma(ESCC)in southern ***:We studied 189 esophageal samples from125 patients from three different groups:(1)102 biopsies from 51 patients with ESCC,with one sample from the tumor and another from normal esophageal mucosa distant from the tumor;(2)50 esophageal biopsies from 37 patients with a previous diagnosis of head and neck squamous cell carcinoma(HNSCC);and(3)37 biopsies from esophageal mucosa with normal appearance from 37 dyspeptic patients,not exposed to smoking or alcohol ***-polymerase chain reaction(PCR)with the MY09/11 and GP5/6 l1primers was used to detect HPV l1 in samples fixed in formalin and stored in paraffin *** PCR reactions were performed with a positive control(cervicovaginal samples),with a negative control(Human Genomic DNA)and with a blank reaction containing all reagents except *** took extreme care to prevent DNA contamination in sample collection,processing,and ***:The histological biopsies confirmed the diagnosis of ESCC in 52 samples(51 from ESCC group and 1 from the HNSCC group)and classified as well differentiated(12/52,23.1%),moderately differentiated(27/52,51.9%)or poorly differentiated(7/52,13.5%).One hundred twenty-eight esophageal biopsies were considered normal(51 from the ESCC group,42 from the HNSCC group and 35 from dyspeptic patients).Nine had esophagitis(7 from the HNSCC and 2 from dyspeptic patients).Of a total of 189 samples,only 6 samples had insufficient material for PCR analysis:1 from mucosa distant from the tumor in a patient with ESCC,3from patients with HNSCC and 2 from patients without *** 183 samples(96.8%)GAPDH,G3PDH and/orβ-globin were amplified,thus indicating the adequacy of the DNA in those *** DNA was negative in all the 183 samples tested:52 with ESCC,9 with esophagitis and 122 with normal esophageal ***:There was no evidence of HP

关键词： Esophageal cancer Esophageal squamous cell carcinoma Human papillomavirus Head and neck cancer Polymerase chain reactions Nested-polymerase chain reaction

Ultrastructural features of the hypopharyngeal glands in the social wasp Polistes versicolor （Hymenoptera： Vespidae）

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2008年第3期15卷 277-284页

作者： Fabio barros Britto Flavio Henrique Caetano Universidade Estadual Paulista Julio de Mesquita Filho Instituto de Bioci~ncias de Rio Claro - Depto. de Biologia Rio Claro SP Brazil

The wasps of the genus Polistes have been considered the key to understanding the evolution of social behavior in Hymenoptera. Several studies have shown that the development of organized insect societies was accompanied by the evolution of structures like exocrine glands, which became specialized to perform specific functions. This article investigates the ultrastructural and cytochemical features of the hypopharyngeal glands of Polistes versicolor. These glands have been studied in depth in social bees, where they occur only in nurses and produce the royal jelly. Our results＇ revealed that these glands basically did not vary among individuals or between sexes. They are constituted by spherical cells, each with a large nucleus and well-developed rough endoplasmic reticulum. Secretion vesicles are abundant, but lipid droplets were not observed, indicating that these glands may not have a role in pheromone synthesis. Acid phosphatase was detected in lysosomes, and also flee in the cytosol, but did not seem to be related with cell death. Thus, our results suggest that the hypopharyngeal glands ofP. versicolor may not have a specialized social role, but could produce digestive enzymes.

关键词： cellular cycle cytochemistry hypopharyngeal glands morphology Polistes,wasps

Assessment of alterability of basalt used for riprap by petrographic examination

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 208-213页

作者： Maria Heloisa barros de Oliveira Frascá MHB Geological Services

All engineering projects consist of several steps, and one of the main tasks is to identify and characterize the most important features of rock types that will be excavated, crushed, or mined for any particular usage purpose, from a single residential building to major works of infrastructure. laboratory investigation on engineering geology is thus conducted in order to determine the most relevant rock properties when designing structures such as mining shafts, tunnels, buildings, or reservoir dams to be built in sites associated with rocks. A wide range of laboratory tests is available, making the correct choice of test methods greatly relevant to determine the key property for the planned use of the rock. This paper is an illustrative case of laboratory testing of basaltic rocks to be used as riprap in a reservoir dam. It shows the important role of the petrographic study carried out to analyze the distribution pattern of smectite clay minerals. Test results are explained for the assessment of rock alterability, an essential aspect for the selection of the most suitable basalt variety for the envisaged conditions of use.

关键词： Rock properties laboratory testing Test methods Petrographic analysis Smectite clay minerals Basaltic rocks Accelerated weathering tests Alterability

A hybrid Monte Carlo study of bond-stretching electron–phonon interactions and charge order in BaBiO_(3)

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2023年第1期9卷 1950-1958页

作者： Benjamin Cohen-Stead Kipton barros Richard Scalettar Steven Johnston Department of Physics and Astronomy The University of TennesseeKnoxvilleTN 37996USA Institute for Advanced Materials and Manufacturing The University of TennesseeKnoxvilleTN 37996USA Theoretical Division and CNlS Los Alamos National LaboratoryLos AlamosNM 87545USA Department of Physics and Astronomy University of CaliforniaDavisCA 95616USA

The relationship between electron–phonon(e-ph)interactions and charge-density-wave(CDW)order in the bismuthate family of high-temperature superconductors remains *** address this question using nonperturbative hybrid Monte Carlo calculations for the parent compound BaBiO_(3).Our model includes the Bi 6s and O 2pσorbitals and coupling to the Bi-O bond-stretching branch of optical phonons via modulations of the Bi-O hopping *** simulate three-dimensional clusters of up to 4000 orbitals,with input model parameters taken from ab initio electronic structure calculations and a phonon energyℏΩ0=60 *** results demonstrate that the coupling to the bond-stretching modes is sufficient to reproduce the CDW transition in this system,despite a relatively small dimensionless *** also find that the transition deviates from the weak-coupling Peierls’*** work demonstrates that off-diagonal e-ph interactions in orbital space are vital in establishing the bismuthate phase diagram.

关键词： stretching phonon charge

Smoking and Health-Related Quality of life(SF-36).A Population-Based Study in Campinas,SP,Brazil

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Health 2014年第12期6卷 1539-1548页

作者： Margareth Guimaraes lima Flávia Silva Arbex Borim Marilisa Berti de Azevedo barros Faculty of Medical Sciences Department of Public HealthState University of CampinasCampinasBrazil

Introduction: Smoking persists as a global and relevant health problem being one of the major risk factors to non-communicable diseases and early death. Studies on the association between smoking and health related quality of life (HRQl) are scarce in Brazil and latin America. The aim of this study was to analyze the HRQl according to smoking status on adults aged 20 to 59 years, living in Campinas, Brazil. Method: It is a population-based cross-sectional study, carried out with data from the Campinas Health Survey developed in 2008/2009. The dependent variables were the eight scales and the two components—physical (PCS) and mental component summary (MCS) of the instrument SF-36, version 2. Means and confidence intervals of the SF-36 scale scores and components were estimated according to smoking (never smokers, former smokers, current smokers) and nicotine dependence (mild, moderate, heavy). Results: The sample comprised 957 individuals (mean age of 37.5 years). Comparing with never smokers, smokers had lower score means in all SF-36 scales, except in physical functioning and role-physical;among the former smokers, lower scores were observed in vitality and mental health. A reduction of the MCS score was observed among smokers and former smokers among men;but in the female population, this reduction was observed only in smokers compared with never smokers. According to the nicotine dependence, it was observed an increasing reduction in MCS scores from mild, to moderate and heavy smokers. Conclusion: Smoking is significantly and negatively associated with HRQl in the studied population. The results point out the importance of the strategic policies against smoking, to reduce morbidity and premature death, but also to increase the quality of life and well-being. It is also important to consider the mental health dimension, since that best mental health can be relevant to promote healthier behaviors.

关键词： Smoking Quality of life Health Status SF-36 Survey

A Brief Review on Hydroxyapatite Nanoparticles Interactions with Biological Constituents

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Biomaterials and Nanobiotechnology 2022年第1期13卷 24-44页

作者： Flávia Carolina lima Torres Edésia Martins barros De Sousa Marcelo Fernandes Cipreste Serviç o de Nanotecnologia (SENAN) Centro de Desenvolvimento da Tecnologia Nuclear (CDTN) Belo Horizonte Brazil Faculdade de Farmácia Universidade Federal de Minas Gerais (UFMG) Belo Horizonte Brazil

With the pursuit of new cancer therapies and more effective treatment to diseases in the last decades, nanotechnology has been an important ally for healthcare professionals and patients in critical clinical conditions. Nanomaterials offer an alternative way to deliver toxic chemotherapeutic drugs to specific biological tissues, specific cells or specific microbial beings, resulting in avoidance of strong side effects or resilience to effective drugs. Among these materials, stands out the hydroxyapatite nanoparticles, a ceramic class of calcium phosphates that present chemical and structural similarities with the mineral phase of the human skeleton’s bone matrix, resulting in important biological features, such as biocompatibility, osteoconductive, osteoinduction and osteoaffinity, which led to a lot of scientific researches to apply these nanoparticles for bone diseases diagnosis and therapeutics. Due to the hydroxyapatite biological activities and due to the possibility to promote chemical and physical modifications in these nanoparticles, they can interact with biological cells or microorganisms in different ways, resulting in multiple potentialities to be explored such as apoptosis induction to cancerous cells, osteogenesis promotion, cellular proliferation, angiogenesis and tissue recovery, in addition to promote cell adhesion and cell uptake. Furthermore, chemical and physical modifications, such as surface functionalization, dopant inclusions and radiolabeling process, allow scientists to track the particle activities in biological environments. In the last decades of scientific productions, the literature brings together important data on how hydroxyapatite nanoparticles interact with biological tissues and such data are crucial for the development of more effective therapeutic and diagnostic agents. In the present review, we intend to compile scholarly information to explore the biological relations of nanosized hydroxyapatite with the human cellular enviro

关键词： Biomaterials Nano-Hydroxyapatite Cell Interactions Chemical Modifications Tissue Engineering Theranostics