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Saturated anisotropic hydraulic conductivity of a compacted lateritic soil

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第5期10卷 986-991页

作者： Roberto Aguiar dos santos Edmundo Rogerio Esquivel Varzea Grande Institute of Engineering Federal University of Mato Grosso Cuiaba Mato Grosso Brazil Sao Carlos School of Engineering University of Sao Paulo Sao Carlos Sao Paulo Brazil

This study focuses on the saturated anisotropic hydraulic conductivity of a compacted lateritic clayey sandy soil. The effects of the molding water content and the confining stress on the anisotropic hydraulic conductivity are investigated. The hydraulic conductivity is measured with a flexible-wall permeameter. Samples are dynamically compacted into the three compaction states of a standard Proctor compaction curve： the dry branch, optimum water content and wet branch. Depending on the molding water content and confining stress, the hydraulic conductivity may increase or decrease. In addition, the results indicate that, when the samples are compacted to the optimum water content, lower hydraulic conductivity is obtained, except at a confining stress equal to 50 kPa. The increase of the confining stress decreases the hydraulic conductivity for each of the evaluated compaction states. In the wet branch, horizontal hy- draulic conductivity is about 8 times higher than the vertical value. The anisotropic hydraulic conduc- tivities of the dry and wet branches decrease when the confining stress increases, and the opposite is observed in the optimum water content state.

关键词： Hydraulic conductivity Anisotropic behavior Lateritic soil Tropical soil Compacted soil

Influence of a non-rotating shoulder on heat generation,microstructure and mechanical properties of dissimilar AA2024/AA7050 FSW joints

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Journal of Materials Science & Technology 2018年第1期34卷 119-127页

作者： Alessandro Barbini Jan Carstensen Jorge F.dos santos Helmholtz-Zentrum Geesthacht Institute of Materials Research Materials Mechanics Solid-State Joining Processes (WMP)

Friction stir welding （FSW） and stationary shoulder friction stir welding （SSFSW） were carried out for the butt joining of dissimilar AA2024-T3 and AA7050-T7651 aluminium alloys with thicknesses of 2 mm. A comparison between the two processes was performed by varying the welding speed while keeping the rotational speed constant, Through the analysis of the force and torque produced during welding and a simple analytical model, it was possible to show that in SSFSW there is more effective coupling with the tool and the heat produced is more efficiently distributed. This process decreases both the welding area and the diffusion at the interface of the two alloys compared with FSW. The minimum microhardness occurred at the advancing side （AS） at the interface between the thermo-mechanically affected zone （TMAZ） and the stir zone （SZ） in both processes, although the decrease was more gradual in SSFSW. This interface is also where all specimens failed for both welding technologies. An increase in tensile strength was measured in SSFSW compared with standard FSW. Furthermore, it was possible to establish the mechanical performance of the material in the fracture zone using digital image correlation.

关键词： Stationary shoulder friction stir welding Friction stir welding Dissimilar welded joints Process analysis Microstructure analysis Mechanical behaviour

Cytokines,cytokine gene polymorphisms and Helicobacter pylori infection:Friend or foe?

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World Journal of Gastroenterology 2014年第18期20卷 5235-5243页

作者： Camila A Figueiredo Cintia rodrigues Marques Ryan dos santos Costa Hugo Bernardino F da Silva Neuza M Alcantara-Neves Instituto de Ciências da Saúde Universidade Federal da BahiaSalvadorBahia 41110-100Brazil

Helicobacter pylori(***)is a flagellated,spiralshaped,microaerophilic Gram-negative bacillus that colonises the gastric mucosa of more than 50%of the human *** is a risk factor for gastritis,ulcer disease and stomach *** against *** is mainly related to Th1/Th17 skewing,and the activation of regulatory T cells is the main strategy used to limit inflammatory responses,which can result in the pathogen persistence and can lead to chronic gastrointestinal diseases,including ***,host genetic factors that affect cytokines may determine differences in the susceptibility to many *** this review,we present the cytokine profiles and the main cytokine gene polymorphisms associated with resistance/susceptibility to *** and discuss how such polymorphisms may influence infection/disease outcomes.

关键词： Helicobacter pylori Stomach cancer Immunity Cytokines Polymorphisms

Proposals of SPT-CPT and DPL-CPT correlations for sandy soils in Brazil

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1152-1158页

作者： Mirella Dalvi dos santos Kátia Vanessa Bicalho Universidade Federal do Espírito Santo VitóriaBrazil

Field tests in geotechnical engineering are fundamental for identification of the underground *** standard penetration test(SPT) is the most commonly used geotechnical approach. There has been an increase both in the use and application of the in situ tests: cone penetration test(CPT) and dynamic probing(DP). Several empirical SPT-CPT and dynamic probing light(DPL)-CPT correlations for sandy soils have been discussed in the literature. New SPT-CPT and DPL-CPT correlations for the sandy soils of the city of Vitoria, in the southeast of Brazil, are suggested in this paper. Statistical analyses to evaluate the quality of the data used are performed, and the suggested correlations are validated with several previous published datasets. The paper also provides some insights into SPT-CPT correlations and soil characteristics(i.e. the mean particle size and the fines fraction of the soil).

关键词： Standard penetration test(SPT) Cone penetration test(CPT) Dynamic probing light(DPL) Correlations Sands Statistical evaluations

Building capabilities in natural resource-dependent economies:An innovation systems analysis of the TVET program in Guyana

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International Journal of Innovation Studies 2019年第1期3卷 1-11页

作者： Chantal dos santos Friedrich-Alexander University Erlangen-Nuremberg 91054 ErlangenGermany

This paper examines Guyana's technical and vocational education and training(TVET)system in relation to diversifying the country's economy away from natural resource *** innovation systems approach is used to examine the effectiveness of TVET as a means of building capabilities in Guyana's key industries,gold and sugar,providing a snapshot of the state of the system in early,*** interviewees across several areas of expertise were consulted in Georgetown,*** analysis of primary and secondary research finds TVET's effectiveness to be limited by a lack of labor market information and funding,energy costs,a“brain drain”,and insufficient information communication technology skills and *** remedies include increasing the frequency of labor market surveys,attracting the Guyanese diaspora back to share knowledge,reducing the cost of energy by taking advantage of domestic renewable energy potential,and setting up a Sovereign Wealth Fund.

关键词： Innovation systems Guyana CARICOM Natural resources TVET

The Use of Triancinolone for the Treatment of Keloid Scars

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Journal of Cosmetics, Dermatological Sciences and Applications 2024年第3期14卷 270-275页

作者： José Humberto Cardoso Resende Luís Otávio Torres Anderson Alves Brandão Delma dos santos Assis Mercadante Jessyka Oliveira Barbosa Batista William Felix de Oliveira Pacheco Elisangelo Aparecido Costa Da Silva Douglas Henrique Farias de Oliveira Nébia Maria Almeida de Figueiredo UNIFAN-Centro Universitrio Alfredo Nasser Aparecida de Goinia Brazil UNIRIO Rio de Janeiro Brazil

Scars, when in good evolution, result in a smooth, thin and discreet tissue. Keloid scars, however, are a type of abnormal and exacerbated repair response to tissue injury, whether in surgical interventions or in various injuries, which present in a prominent and gross way. In this context, there is an excess of collagen deposition in the tissue repair process, which can lead to the formation of keloids. The diagnosis of the condition presented is made by the medical professional or by the patient himself after the surgical intervention or skin injury. Under this analysis, protruding, rough and bad-looking scars are identified. In addition, we highlight the existence of keloids similar to large tumors, described as Jorge Lobo disease. The treatment encompasses massages, compressions, corticosteroids, chemotherapy, collagenase and cryotherapy. At first, we used corticosteroid-based massages, and then we started using compressive dressings until we started intrakeloid infiltrations with injectable triamcinolone. Triamcinolone 10 mg injectable—1/10—in 0.9% saline, with syringe and fixed needle 0.3 mm × 8 mm, intralesional infiltrate, in this context, proved to be effective for its treatment when applied sequentially and linearly. In cases where the medication was applied, there was an improvement after 21 days of application and a definitive improvement 2 months after the injury. In comparison, on the other hand, patients who were not subjected to the application of the medication may improve after 4 months of the injury or worsen compared to the initial case. We have come to the conclusion that this procedure may be one of the chosen ones for the treatment of keloid scars, being one of the most recommended for cases of keloid already installed.

关键词： Keloid Scar Hypertrophy Collagen Affection

In Silico and in Vitro Analysis of Pyrazolone Derivatives against Zika Virus and Identification of Potential NS5 Methyltransferase Inhibitors by Molecular Docking

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Journal of Biosciences and Medicines 2024年第7期12卷 214-229页

作者： Luciene Soares Silva Tiago Soares Barbosa Maria Leonisa Sanchez-Nuñez Aldenise Mont Serrat Rosa da Silva Vitor Won-Held Rabelo Leonardo dos santos Corrêa Amorim Leonardo Alves Miceli Percilene Fazolin Vegi Alice Bernardino Helena Carla Castro Izabel Christina Nunes de Palmer Paixão Science and Biotechnology Graduate Program Department of Cellular and Molecular Biology Institute of Biology Fluminense Federal University Niteri Brazil Science and Biotechnology Graduate Program Department of Cellular and Molecular Biology Institute of Biology Fluminense Federal University Niterói Brazil Laboratory of Antibiotics Biochemistry Teaching and Molecular Modeling Institute of Biology Fluminense Federal University Niterói Brazil Laboratory of Organic Chemistry at the Institute of Chemistry Institute of Biology Fluminense Federal University Niterói Brazil

Zika virus (ZIKV), a mosquito-borne flavivirus, has been associated with benign infections for decades. However, it has become a public health concern due to its association with severe fetal and neurological complications. Although many efforts have been made to control ZIKV infection, approved vaccines or antiviral drugs are still lacking. Consequently, the development of new effective anti-ZIKV agents is urgently needed. In this context, we investigated the antiviral potential of pyrazolone derivatives against ZIKV replication using in silico and in vitro methods. The four pyrazolone derivatives evaluated (1a, 1b, 1c, and 1d) inhibited over 50% of ZIKV replication with low cytotoxicity. Among them, compound 1b exhibited the most potent activity (EC50 = 4.3 μM) and the highest selectivity (SI = 342). Mechanism of action studies indicated that these compounds act at early stages of virus replication, and compound 1b can also directly inactivate ZIKV particles. Molecular docking studies suggested that these compounds can bind to and block the activity of ZIKV NS5 methyltransferase. Finally, pharmacokinetic and toxicological predictions have reinforced the safety and drug-like profiles of these derivatives. In conclusion, the pyrazolone scaffold proved to be valuable for anti-ZIKV drug development, and the derivatives studied deserve further investigation.

关键词： Zika Pyrazolone NS5 Methyltransferase Antivirals

Distinguishing the Regional Atmospheric Controls on Precipitation Isotopic Variability in the Central-Southeast Portion of Brazil

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Advances in Atmospheric Sciences 2022年第10期39卷 1693-1708,I0018-I0020页

作者： Vinícius dos santos Peter MARSHALL FLEMING Luís HENRIQUE MANCINI Stela DALVA santos COTA Graziele Beatriz de LIMA Rafaela rodrigues GOMES Roberto Eduardo KIRCHHEIM Ricardo SANCHÉZ-MURILLO Didier GASTMANS São Paulo State University(UNESP) Environmental Studies Center.Av.24ABased1515-Bela Vista13.506-900Rio Claro(SP)Brazil Center for the Development of the Nuclear Technology(CDTN-CNEN) Av.Presidente Antônio Carlos6.627Campus da UFMG-Pampulha31270-90Belo Horizonte(MG)Brazil Universidade de Brasília-UnB Instituto de GeociênciasLaboratório de Isótopos Estáveis.Campus"Darcy Ribeiro"Asa Norte70.910-900Brasília(DF)Brasil Hydrology and Territorial Management Directory(DHT) The Geological Survey of Brazil(CPRM-SGB)São Paulo(SP)Brazil University of Texas at Arlington Earth and Environmental Sciences Department500 Yates StreetArlingtonTexas76019USA Stable Isotopes Research Group and Water Resources Management Laboratory Universidad NacionalHerediaCosta Rica

Precipitation isotope ratios(O and H)record the history of water phase transitions and fractionation processes during moisture transport and rainfall ***,we evaluated the isotopic composition of precipitation over the central-southeastern region of Brazil at different *** isotopic compositions were associated with classical effects(rainfall amount,seasonality,and continentality),demonstrating the importance of vapor recirculation processes and different regional atmospheric systems(South American Convergence Zone-SACZ and Cold Fronts-CF).While moisture recycling and regional atmospheric processes may also be observed on a daily timescale,classical effects such as the amount effect were not strongly correlated(δ^(18)O-precipitation rate r≤-0.37).Daily variability revealed specific climatic features,such asδ^(18)O depleted values(~-6‰to-8‰)during the wet season were associated with strong convective activity and large moisture *** isotopic analysis revealed the role of different moisture sources and transport *** ratios combined with d-excess explain how atmospheric recirculation processes interact with convective activity during rainfall formation *** findings provide a new understanding of rainfall sampling timescales and highlight the importance of water isotopes to decipher key hydrometeorological processes in a complex spatial and temporal context in central-southeastern Brazil.

关键词： precipitation stable water isotopes d-excess moisture source and transport southern Atlantic Ocean and Amazon

A Numerical Comparison Between Quasi-Monte Carlo and Sparse Grid Stochastic Collocation Methods

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Communications in Computational Physics 2012年第9期12卷 1051-1069页

作者： Juarez dos santos Azevedo Saulo Pomponet Oliveira CETEC-UFRB Centro44380-000Cruz das Almas-BABrazil.2 DMAT-UFPRCentro Politecnico81531-980Curitiba-PRBrazil

Quasi-Monte Carlo methods and stochastic collocation methods based on sparse grids have become popular with solving stochastic partial differential *** methods use deterministic points for multi-dimensional integration or interpolation without suffering from the curse of *** is not evident which method is best,specially on random models of physical *** numerically study the error of quasi-Monte Carlo and sparse gridmethods in the context of groundwater flow in heterogeneous *** particular,we consider the dependence of the variance error on the stochastic dimension and the number of samples/collocation points for steady flow problems in which the hydraulic conductivity is a lognormal *** suitability of each technique is identified in terms of computational cost and error tolerance.

关键词： Karhunen-Loève expansion Monte Carlo quasi-Monte Carlo sparse grid