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Study of Brazilian Woods Using Gamma-Ray Sources

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Journal of Physical Science and Application 2014年第5期4卷 304-309页

作者： gilberto carvalho Leonardo Gondim de Andrade e Silva Radiation Technology Centre Nuclear and Energy Research Institute National Nuclear Energy Commission (IPEN-CNEN/SP Sao Paulo 05508-000 Brazil

Due to the availability and particular features, wood was one of the first materials used by mankind with a wide variety of applications. It can be used as raw-material for paper and cellulose manufacturing; in industries such as chemical, naval, furniture, sports goods, toys, and musical instruments; in building construction and in the distribution of electric energy. Wood has been widely researched; therefore, wood researchers know that several aspects such as temperature, latitude, longitude, altitude, sunlight, soil, and rainfall index interfere as to the growth of trees. This behavior explains why the average of physical chemical properties is important in wood *** of the researchers consider density to be the most important wood property because of its straight relationship with the physical and mechanical properties in wood. There are three types of wood density： basic, apparent and green. The apparent density was used here at 12% of moisture content. In this study, four different types of wood were used：＂Freijo＂, ＂Jequitiba＂, ＂Muiracatiara＂ and ＂Ipe＂. For wood density determination by non-conventional method, ^241Am, ^133Ba and ^137Cs gamma-ray sources, a NaI scintillation detector and a counter were used. The results demonstrated that this technique is quick and accurate. Considering the nuclear parameters obtained as half-value layers and linear absorption coefficients,^ 137Cs demonstrated to be the best option to be used for inspection of the physical integrity of electric wooden poles and live trees for future works.

关键词： Brazilian woods density gamma-ray.

High- and Low-Rearing Rats Differ in the Brain Excitability Controlled by the Allosteric Benzodiazepine Site in the GABA_(A) Receptor

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Journal of Behavioral and Brain Science 2012年第3期2卷 315-325页

作者： Rosana Alves Jose gilberto Barbosa de carvalho Marco Antonio Campana Venditti Departamento de Psicobiologia Escola Paulista de MedicinaUniversidade Federal de Sao PauloRua BotucatuBrazil

Rearing is an exploratory behavior induced by novelty, such as exposure to an open field. Stimulation of certain brain regions, including the hippocampus, induces both rearing and clonic convulsions. Brain excitability is controlled by gamma-aminobutyric acid (GABA) inhibitory neurotransmission through its ionotropic GABAA/allosteric benzodiazepine site. Drugs that decrease GABAA receptor fast inhibitory neurotransmission induce clonic convulsions and rearing when injected into the hippocampus. Therefore, individual differences in rearing behavior may be related to the susceptibility to clonic convulsions, which could involve differences in brain excitability controlled by GABAA/allosteric benzodiazepine site receptors. Adult, male Wistar rats were divided into high- (HR) and low-rearing (LR) groups based on the number of rearings in the open field test. Groups of HR and LR rats were challenged with convulsant drugs that antagonize GABA neurotransmission via different mechanisms of action (3-mercaptopropionic acid, a glutamate decarboxilase inhibitor;bicuculline, a GABAA receptor antagonist;pentylenetetrazol and picrotoxin, both GABAA receptor chloride channel blockers and DMCM, a benzodiazepine inverse agonist). The convulsant doses that induced 50% of clonic convulsions were determined for each drug. The LR rats had a higher susceptibility (a lower convulsant dose 50%) to clonic convulsions induced by DMCM than the HR rats, but there were no differences between the groups in the susceptibility to tonic convulsions induced by the same drug. There were no significant differences in the convulsant dose 50% for clonic convulsions between the groups for all other drugs injected. In another experiment, additional HR and LR rats were injected with a sedative-hypnotic dose of diazepam, which caused a significantly higher hypnotic effect (sleeping-time) in the LR rats than in the HR rats. The LR group was also shown to have a significantly lower density of [3H]-Flunitrazep

关键词： Open Field Rearing Behavior Clonic Convulsion Diazepam Sleep Benzodiazepine DMCM GABA_(A) Receptor [^(3)H]-Flunitrazepam Binding Hippocampus Novelty Stress

Multivariate Analysis of Extreme Physical, Biological and Chemical Patterns in the Dynamics of Aquatic Ecosystem

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Journal of Environmental Protection 2015年第8期6卷 885-901页

作者： Marilia Mitidieri Fernandes de Oliveira gilberto carvalho Pereira Nelson Francisco Favilla Ebecken Jorge Luiz Fernandes de Oliveira Center of Technology Federal University of Rio de Janeiro-Civil Engineering Postgraduate Program-COPPE/UFRJ Rio de Janeiro Brazil Geography Postgraduate Program Geoscience Institute of Fluminense Federal University-UFF Niterói Brazil

This study is a part of the research in monitoring systems of environmental impacts in coastal re-gions in order to develop trophic dynamic models to be used in the aquatic systems management. Meteorological influences in the variability of the nutrients, larvae concentration, dissolved oxygen (DO) and chlorophyll a were investigated in a region where upwelling occurs. Extreme seasonal variations of reanalysis, QuikSCAT, and surface stations from the southeast coast of Brazil, as well as, surface seawater data collected in Anjos Bay, Arraial do Cabo city northeast of Rio de Janeiro state, are analyzed. Seasonality and correlations are applied to verify the relationship between them, considering minimum values of sea surface temperature (SST) and sea level variation and maximum values of the other variables. Principal Component Analysis (PCA) and Hierarquical Cluster Analysis (HCA) are applied to verify spatial and temporal variances and to describe more clearly the structure of the local ecosystem. The seasonality of northeasterly extreme wind stress follows the seasonal pattern expected for the study area with peaks during spring. The SST has a well-defined seasonal pattern with maximum peaks from February to July and minimum peaks from September to January. Chlorophyll a presents higher seasonal peak in February, being in accordance with DO;both are related to the maximum primary productivity. Correlations of the physical variables (local and remote) with nutrients and larvae present a relatively similar pattern around 0.5, showing these variables have a reasonable interaction with the meteorological forcing. PCA shows a strong variability in pressure data around 0.9, which may be related to the seasonal variations in South Atlantic subtropical anticyclone (SASA) and consequently to the occurrence of upwelling in the region. HCA shows the twenty-five parameters into two big clusters with predominance of biotic variables in one side and abiotic ones at the other. T

关键词： Larvae Nutrient Concentrations Coastal Waters Brazil Upwelling

Design multifunctional Mg–Zr coatings regulating Mg alloy bioabsorption

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Journal of Magnesium and Alloys 2024年第4期12卷 1461-1478页

作者： Zohra Benzarti Sandesh Itani JoséDavid Castro Sandra carvalho Ana Sofia Ramos University of Coimbra CEMMPREARISEDepartment of Mechanical EngineeringRua Luís Reis Santos3030-788CoimbraPortugal Laboratory of Multifunctional Materials and Applications(LaMMA) Department of PhysicsFaculty of Sciences of SfaxUniversity of SfaxSoukra Road km 3.5B.P.1171Sfax3000Tunisia

Magnesium(Mg)alloys are widely used for temporary bone implants due to their favorable biodegradability,cytocompatibility,hemocompatibility,and close mechanical properties to ***,rapid degradation and inadequate strength limit their *** overcome this,the direct current magnetron sputtering technique is employed for surface coating in Mg-based alloys using various zirconium(Zr)*** approach presents a promising strategy for simultaneously improving corrosion resistance,maintaining biocompatibility,and enhancing strength without compromising *** leveraging Mg’s inherent biodegradability,it has the potential to minimize the need for secondary surgeries,thereby reducing costs and *** paper is a systematic study aimed at understanding the corrosion mechanisms of Mg–Zr coatings,denoted Mg-xZr(x=0–5 at.%).Zr-doped coatings exhibited columnar growth leading to denser and refined structures with increasing Zr *** analysis confirmed the presence of the Mg(00.2)basal plane,shifting towards higher angles(1.15°)with 5 at.%Zr doping due to lattice parameter changes(i.e.,decrease and increase of“c”and“a”lattice parameters,respectively).Mg–Zr coatings exhibited“liquidphilic”behavior,while Young’s modulus retained a steady value around 80 GPa across all ***,the hardness has significantly improved across all samples’coating,reaching the highest value of(2.2±0.3)GPa for 5 at.%*** testing in simulated body fluid(SBF)at 37℃ revealed a significant enhancement in corrosion resistance for Mg–Zr coatings containing 1.0–3.4 at.%*** with the 5 at.%Zr coating which exhibited a corrosion rate of 32 mm/year,these coatings displayed lower corrosion rates,ranging from 1 to 12 mm/*** synergistic enhancement in mechanical properties and corrosion resistance,achieved with 2.0–3.4 at.%Zr,suggests potential ability for reducing stress shielding and controlled degradation performance,and consequentl

关键词： Mg-Zr coatings Magnetron sputtering Nanoindentation Corrosion resistance Bone implants

Review on the state-of-the-art and challenges in the MgB_(2)component manufacturing for superconducting applications

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Superconductivity 2024年第1期9卷 50-64页

作者： Fabiano carvalho de Castro Sene Department of Industrial and Systems Engineering University of TennesseeKnoxvilleUnited States

Since the discovery of MgB_(2)as a superconductor,several research groups worldwide have studied the superconducting mechanisms due to the dual gap nature of MgB_(2),as well as attempted to produce such a compound in wires,tapes,bulks,and thin films for a plethora of *** MgB_(2)carries the promise of replacing Niobium‐based superconductors in low‐field applications,less‐than‐desirable performance and in‐operation stability has slowed down such a *** the properties and nature of the superconductivity of MgB_(2)are fairly known,the reproduction of its properties at manufacturing scales remains an unsolved ***,this manuscript presents a systematic review on fundamental properties,phase formation,growth kinetics,and superconducting properties of MgB_(2)‐based components such as multi‐and mono‐core wires,bulks,and thin ***,challenges,and shortcomings are utilized in consolidating research questions and directions pertaining to the manufacturing of MgB_(2)superconducting ***,we evaluate the technological readiness of MgB_(2)‐based devices for applications in fusion energy systems.

关键词： MgB_(2) Superconductor manufacturing Technology readiness Review Low‐Field applications

Determination of critical state line(CSL)for silty-sandy iron ore tailings subjected to low-high confining pressures

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1684-1695页

作者： Nilo Cesar Consoli João Vítor de Azambuja carvalho Alexia Cindy Wagner Hugo Carlos Scheuermann Filho Inácio carvalho Pedro Pazzoto Cacciari João Paulo de Sousa Silva Civil Engineering Universidade Federal do Rio Grande do SulPorto AlegreRS90035-190Brazil Exploration and Mineral Projects-Mineral Development Centre VALE S.A.Santa LuziaMG33040-900Brazil Department of Civil Geological and Mining EngineeringPolytechnique MontrealQuebecH3C 3A7Canada

The disposal of filtered tailings in high dry stacks can induce particle breakage,changing the material's behaviour during the structure's *** grading changes influence material properties at the critical state,and this is not mature for intermediate artificial soils(tailings)in a broad range of confining *** this paper,it aims to describe the behaviour of iron ore tailings in a spectrum of confining pressures broader than the reported in previous studies.A series of consolidated drained(CD)triaxial tests was carried out with confining pressures ranging from 0.075 MPa to 120 *** results show that the amount of breakage plays an essential role in the response of iron ore *** existence of curved critical state line(CSL)in both specific volume(ν)-logarithm of mean effective stress(p′)and deviatoric stress(q)-mean effective stress(p′)planes,and different responses in the deviatoric stress-axial strain-volumetric strain curves were *** inverse S-shaped equation was proposed to represent the silty-sandy tailings'behaviour up to high pressures onν-lnp′*** proposed equation provides a basis for enhancing constitutive models and considers the evolution of the grading up to severe loading *** adjustment considered three regions with different responses associated with particle breakage at different pressure levels.

关键词： Tailings Iron ore tailings dry stacking Silty-sandy material Critical state soil mechanics High confining pressures Particle breakage

How far have we come?Review of main public policies to reduce landslide impacts in Brazil

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Journal of Mountain Science 2024年第9期21卷 2891-2904页

作者： Bianca carvalho VIEIRA Tiago Damas MARTINS Telma Mendes da SILVA JoséEduardo BONINI Department of Geography University of São PauloAvenida Professor Lineu Prestes 05508-000Brazil Cities Institute Federal University of São PauloAvenida Jacu-Pêssego 08260-001Brazil Department of Geography Federal University of Rio de JaneiroAvenida Athos da Silveira Ramos 21941-916Brazil

During the rainy season in Brazil,landslides can have catastrophic consequences,including loss of life,damage to urban infrastructure and significant economic ***,more than eight million people in Brazil live in disaster-prone *** objective of this article is to present a chronological review of the principal policies and programmes at the national,state,and municipal levels,with an emphasis on their key actions aimed at mitigating the impact of disasters related to natural hazards,particularly *** analysis was based on official records of public policies from the national,state,and municipal *** results show that several initiatives were initially developed at the local and regional ***,it was not until the late 1980s that a comprehensive organisation of civil protection at the national level emerged as a response *** is possible to highlight three phases(understanding,coexistence,and prevention)of institutional action focused on risk management in the face of *** the growing knowledge of risk scenarios,disasters continue to occur in Brazil on an annual basis,revealing several obstacles to reducing their impact,particularly given the social and economic disparities between Brazilian regions and the applicability of public policies that must overcome the limitations of each municipality.

关键词： Disasters Risk Mitigation Prevention Legislation Civil Defense Natural Hazards

Lipedema:A common though often unrecognized condition

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Chinese Journal of Plastic and Reconstructive Surgery 2024年第3期6卷 149-153页

作者： Rafael carvalho Private Practice R.Iolanda del Nero Barco101PirassunungaSao Paulo13631-064Brazil

Lipedema is a chronic disorder primarily affecting women,characterized by abnormal fat deposition in the extremities,leading to pain,mobility issues,and psychological *** fat deposits are clear-cut and spare hands and *** misdiagnosed as lymphedema,its prevalence remains uncertain due to a lack of universally accepted diagnostic criteria and difficulty in differentiating it from obesity or *** factors and hormonal influences are likely related to the pathophysiology of the disease,though the specific causes remain *** techniques may aid evaluation,but no definitive test exists,and diagnosis is made *** treatments such as lifestyle modifications and compression garments are considered first-line treatments,while surgical options such as liposuction and lipectomy are reserved for severe or refractory *** support may be recommended,given lipedema’s impact on quality of life and *** review aims to present the current understanding of this condition,including challenges in diagnosis,current guideline recommendations for clinical care,and associated comorbid conditions.

关键词： Lipedema Obesity Lymphedema Liposuction Lipectomy

Starch Orodispersible Film Loaded with Melatonin for Human Supplementation

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Journal of Renewable Materials 2024年第7期12卷 1343-1354页

作者： Fabio Tamanini Tatiane Zucchini de Souza Creusa Sayuri Tahara Amaral Antônio JoséFelix carvalho Eliane Trovatti Department of Health and Biological Sciences University of Araraquara(UNIARA)São Paulo14801-340Brazil Department of Materials Engineering São Carlos School of EngineeringUniversity of São PauloSão Paulo13563-120Brazil

An innovative pharmaceutical form for administering melatonin,based on starch orodispersibleﬁlm(ODF),was designed and *** composition of the ODF included starch as the polymer matrix,the active drug melatonin,and a ***,a natural hormone produced by the pineal gland in the brain,can be absorbed by passive diffusion across the mucous membrane,resulting in improved bioavailability when compared to conventional oral *** study shows a simple and efﬁcient method for preparing melatonin-loaded orodispersibleﬁlms with a physically stable and commercially viable matrix,suitable for use in the pharmaceutical ***ﬁlms were prepared by treating the starch with microwave irradiation,followed by plasticization with glycerol,melatonin loading and drying by solvent *** tests showed theﬁlms’robustness,with a modulus of approximately 97 MPa,indicating good handling *** uptake analysis showed fast water absorption,reaching about 150%within 2 min,indicating its fast oral disintegration *** tests in artiﬁcial saliva and dissolution studies indicated the release of the drug in min-utes,indicating the potential properties of theﬁlm for oral drug *** the best of our knowledge,there is no melatonin ODF based on starch described in the literature.

关键词： Starch orodispersibleﬁlm melatonin drug delivery