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Molecular and cellular mechanisms of neuroprotection by oligopeptides from snake venoms

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BIOCELL 2024年第6期48卷 897-904页

作者： carlos ALBERTO-silva BRENDA RUFINO DA silva Natural and Humanities Sciences Center Experimental Morphophysiology LaboratoryFederal University of ABC(UFABC)São Bernardo do CampoSão PauloBrazil

Venom snake-derived peptides have multiple biochemical,pharmacological,and toxicological proﬁles,allowing for the discovery of new medicinal products and therapeutic *** review speciﬁcally examines the fundamental elements of neuroprotection offered by different oligopeptides derived from snake *** also includes a brief evaluation of short peptides that are being considered as potential therapeutic ***-rich peptides and tryptophyllin family peptides isolated from the crude venom of Viperidae family snakes,speciﬁcally Bothrops atrox,Bothrops jararaca,and Bothrops moojeni,have been shown to have pro-survival properties,the ability to reduce oxidative stress,and the ability to promote cell viability and mitochondrial *** signiﬁcant mechanisms are related to the neuroprotection mediated by snake venom oligopeptides:(1)Activation of the L-arginine metabolite pathway,such as polyamines from ornithine metabolism,which reduces N-methyl-D-aspartate(NMDA)-type glutamate receptor activity;(2)Enhancement of cell viability by activating the nerve growth factor-signaling pathway;and(3)Activation of the Muscarinic acetylcholine receptor subtype M1(mAChR-M1).These small peptides show promise as neuroprotective agents against a variety of neurodegenerative disorders.

关键词： Neuroprotective peptides Neurodegenerative disease Oxidative stress Reactive oxygen species Biopeptides

Perpendicularly Self-Oriented and Shape-Controlled L10-FePt Nanorods Directly Synthesized by a Temperature-Modulated Process

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Nano Research 2011年第7期4卷 666-674页

作者： Tiago Luis da silva Laudemir carlos Varanda Colloidal Materials Group Instituto de Quimica de Sao Carlos Universidade de Sao Paulo--USP Sao Carlos PO Box 780 13566-590 Brazil

The synthesis and self-assembly of tetragonal phase-containing L10-Fe55Pt45 nanorods with high coercive field is described. The experimental procedure resulted in a tetragonal/cubic phase ratio close to 1：1 for the as-synthesized nanoparticles. Using different surfactant/solvent proportions in the process allowed control of particle morphology from nanospheres to nanowires. Monodisperse nanorods with lengths of 60 ＋ 5 nm and diameters of 2-3 nm were self-assembled in a perpendicular oriented array onto a substrate surface using hexadecylamine as organic spacer. Magnetic alignment and properties assigned, respectively, to the shape anisotropy and the tetragonal phase suggest that the self-assembled materials are a strong candidate to solve the problem of random magnetic alignment observed in FePt nanospheres leading to applications in ultrahigh magnetic recording （UHMR） systems capable of achieving a performance of the order of terabits/in2.

关键词： Magnetic materials data storage FePt nanorods self-assembl~ perpendicular magnetic alignment

A Finite Element Study of the Influence of Graphite Nodule Characteristics on a Subsurface Crack in a Ductile Cast Iron Matrix under a Contact Load

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Computer Modeling in Engineering & Sciences 2018年第10期117卷 59-71页

作者： Guilherme Suguinoshita carlos Henrique da silva Marco Antonio Luersen Department of Mechanical Engineering Federal University of Technology-Parana(UTFPR)Rua Deputado Heitor Alencar Furtado5000CEP 81280-340CuritibaBrazil

This paper describes a study of the effects of graphite nodule characteristics on a subsurface crack in austempered ductile iron(ADI).A representative specimen of ADI,subjected to sliding contact load,is modeled using finite elements aiming to obtain the shear stress intensity factor(KII).The parameters varied were(i)the nodule diameter(two different values were considered),(ii)the distance between the nodule and the tip of the crack and(iii)the position of the load relative to the tip of the *** results of the numerical simulations show that the smaller diameter nodule has a larger influence on KII,suggesting a higher contact fatigue crack propagation rate in the material with the smaller *** results are the opposite of those observed in experimental studies and would appear to indicate that other factors should be also considered to ensure realistic estimates of the contact fatigue strength of ADI.

关键词： Austempered ductile iron subsurface crack stress intensity factor finite element analysis graphite nodule

Authigenic titanite in weathered basalts: Implications for paleoatmospheric reconstructions

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Geoscience Frontiers 2020年第6期11卷 2183-2196页

作者： Alexey A.Novoselov Dailto silva carlos Roberto de Souza Filho Institute of Applied Economic Geology Universidad de ConcepcionConcepcionChile Institute of Geosciences University of CampinasCampinasSPBrazil

The stability of titanite is sensitive to temperature and partial pressure of *** finding of authigenic titanite grains in weathering regolith formed on Parana basalts,Brazil,under tropical climatic conditions,reveals the thermodynamically-driven conversion from calcite to titanite at elevated ambient *** unusual nowadays,this phase transition provides important implications for the understanding of silicate weathering in earlier geological *** types of secondary titanites were identified in the weathering profile of the study *** tiny grains of 10 μm are forming in the microscopic voids in the ***,large fractures filled with Fe-rich clay minerals contain bigger specimens of up to 170μ*** titanites of second type often coexist with chalcedony and *** carbonate minerals were found in the weathering *** sphene can be discriminated from other titanite types by its strong positive Eu anomaly,increased Al2 O3 content and low content of trace *** specific chemical composition and reactive transport modeling link this secondary mineral with dissolution of *** titanite precipitation is controlled by slow diffusion in poorly-aerated,highly-alkaline pore *** subaerial weathering of basaltic rocks provides a significant reservoir for atmospheric ***,the deposition of carbonate minerals is thermodynamically avoided at the stability field of *** demonstrate a complex feedback between CO2 and soil *** rise in pCO2 triggers the precipitation of calcite in the weathering regolith,but the greenhouse effect increasing the temperature can cease carbonate *** titanites were found in several paleosols and at least a part of them can be of weathering origin.

关键词： Titanite Sphene Calcite Paleosols Weathering Paleoclimates

Application of advanced oxidation processes for removing salicylic acid from synthetic wastewaters

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Chinese Chemical Letters 2010年第1期21卷 101-104页

作者： Djalma Ribeiro da silva carlos A.Martinez-Huítle Universidade Federal do Rio Grande do Norte CCET-Departamento de QuimicaLagoa Nova-CEP 59.072-970 Brazil Universidade Federal do Rio Grande do Norte CCET-Departamento de QuimicaLagoa Nova-CEP 59.072.970 Brazil University of Milan Department of ChemistryCeloria 220133 MilanItaly

In this study,advanced oxidation processes(AOPs) such as anodic oxidation(AO),UV/H_2O_2 and Fenton processes(FP) were investigated for the degradation of salicylic acid(SA) in lab-scale ***-doped diamond(BDD) film electrodes using Ta as substrates were employed for AO of *** the case of FP and UV/H_2O_2,most favorable experimental conditions were determined for each process and these were used for comparing with AO *** study showed that the FP was the most effective process under aci...

关键词： Advanced oxidation processes Salicylic acid(SA) Anodic oxidation Ta/BDD Electrocatalytic activity

Global epidemiology of sexually transmitted diseases

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Asian Journal of Andrology 2008年第1期10卷 110-114页

作者： carlos T. Da Ros Caio da silva Schmitt Urology Department Mae de Deus Hospital Porto Alegre RS 90450180 Brazil

Sexually transmitted diseases （STDs） are among the first ten causes of unpleasant diseases in young adult males in developing countries and the second major cause of unpleasant diseases in young adult women. Adolescents and young adults （15-24 years old） make up only 25% of the sexually active population, but represent almost 50% of all new acquired STDs. In general, STDs are epidemics and present an enormous health and economic consequences. An adequate screening for STDs should be done on a routine basis in every part of the world. Many STDs are asymptomatic and therefore can difficult to control. The purpose of reporting of STDs is to ensure that persons who are infected will be quickly diagnosed and appropriately treated to control the spread of infection and also so that partners are notified, tested and appropriately treated. It is estimated that reported cases of STDs represent only 50%-80% of reportable STD infections in the United States, reflecting limited screening and low disease reporting. High-risk sexual behavior is a highly contributive factor of this process as it often leads to teenage pregnancies and HIV/AIDS. One possible explanation for this behavior is that people do not have enough information about the transmission of STDs or ignore the precautions required for safe sex. Approximately 60% of new HIV infections worldwide occur in young people. The frequency of high-risk behaviors among youths may also be influenced by opportunity to engage in them, particularly the amount of time that they are unsupervised by adults. However, in diagnosing and treating these patients, we can effectively prevent the spread of HIV/AIDS. Individuals infected with STDs are 5-10 times more likely than uninfected individuals to acquire or transmit HIV through sexual contact. The breaking of the genital tract lining or skin creates a portal of entry for HIV and, hence, HIV-infected individuals with other STDs are more likely to shed HIV in their genital secretions. T

关键词： sexually transmitted diseases safe sex condom young people

Validation and adaptation of the Physical Activity Enjoyment Scale (PACES) in fitness group exercisers

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Journal of Sport and Health Science 2020年第4期9卷 352-357页

作者： Pedro Teques Luıs Calmeiro carlos silva Carla Borrego N2i Polytechnic Institute of Maia Research CentreMaia 4475-690Portugal CIPER Interdisciplinary Centre for the Study of Human PerformanceCruz Quebrada 1499-002Portugal Abertay University School of Social and Health SciencesDundee DD11HGUK Polytechnic Institute of Santarem Sport Sciences School of Rio MaiorSantarem 2001-904Portugal CIEQV—Life Quality Research Center Santarem 2001-904Portugal

Background:Recently,Mullen et al.(2011)presented an 8-item version of the Physical Activity Enjoyment Scale(PACES)that provides a valid instrument for assessing enjoyment in physical *** present paper investigated the psychometric properties of a Portuguese adaptation of ***:After a process of back-to-back translation into Portuguese,395 members of fitness centers who ranged in age from 18 to 66 years(31.11§8.90,mean§SD)completed the translated version of the *** average,participants had 3.2 years of experience in fitness group classes and practiced for approximately 3.3 times per ***:An initial exploratory factor analysis(n=139)revealed a unidimensional structure with factor loadings ranging from 0.79 to *** also showed acceptable internal consistency.A confirmatory factor analysis in an independent sample(n=256)provided additional support for the unidimensional structure of the *** addition,moderate positive correlations between enjoyment and intrinsic and identified regulation,and moderate negative correlations between enjoyment and external and amotivation,demonstrate the convergent validity of the ***,measurement invariance between 2 independent samples was also ***:The 8-item Portuguese version of PACES is a valid and reliable instrument for measuring enjoyment of physical activity in Portuguese adult fitness exercisers,and it is therefore suitable to use as a measure of affect in exercise adherence interventions studies.

关键词： Confirmatory factor analysis Construct validity Enjoyment Exploratory factor analysis Fitness Measurement invariance Self-determination theory

Recovery of rare-earth metals from aqueous solutions by bio/adsorption using non-conventional materials:a review with recent studies and promising approaches in column applications

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Journal of Rare Earths 2020年第4期38卷 339-355页

作者： Talles Barcelos da Costa Meuris Gurgel carlos da silva Melissa Gurgel Adeodato Vieira University of Campinas School of Chemical EngineeringAlbert Einstein Avenue50013083e852 CampinasBrazil

The recovery of rare-earth metals(REMs)is of great economic and environmental interest,because of their high market prices and various industrial ***,with the increasing demand for high-purity rare-earth compounds,the separation and purification of these elements have gained considerable *** bio/adsorption process has been considered an alternative to recover these elements,by its simplicity,low cost and efficiency for recovery of REMs at low *** review article presents the recent progress regarding REM bio/adsorption published literature in batch system by different non-conventional bio/adsorbents,as well as a critical analysis of the technological challenges to be faced and future *** this purpose,the best application model(isotherm,kinetics),thermodynamic quantities and selection of eluents for desorption studies are also ***,in this review,the application of different bio/adsorbent materials were reviewed extensively in terms of the removal and recovery of REMs in continuous fixed-bed adsorption and regeneration ***,future aspects in bio/adsorption research and prospects for commercial applications were discussed.

关键词： Rare-earth metals Bio/adsorbents Adsorption kinetics Isotherm Batch desorption Continuous fixed-bed adsorption

Effect of rare-earth oxides on properties of silicon nitride obtained by normal sintering and sinter-HIP

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Journal of Rare Earths 2012年第11期30卷 1177-1183页

作者： Cecilia C.Guedes-silva Flávio Machado de Souza Carvalho José carlos Bressiani Nuclear and Energy Research Institute-IPEN/CNEN Geoscience Institute-IGC/USP

This paper presented the microstructure, mechanical properties and oxidation behavior of silicon nitride obtained by both conventional sintering and sintering followed by hot isostatic pressing （HIP）. Silicon nitride with additives such as 5 wt.% Al2O3 and 5 wt.% Ln203 （Ln= La, La concentrate, Gd or La＋Gd） were studied. The results revealed that Gd203 additions increased the formation of elongated grains of β-Si3N4, the fracture toughness and oxidation resistance. La2O3 additions led to higher densification and hardness values, while addition of La2O3 concentrate promoted the formation of materials with intermediate properties, compared to the other studied compositions. Hot isostatic pressing increased the hardness but decreased the fracture toughness of the material, mainly because it allowed residual pores to close and also reduced the average aspect ratio of β-Si3N4 grains.

关键词： rare earths silicon nitride properties normal sintering sinter-HIP