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Microbial Carbon, Mineral-N and Soil Nutrients in Indigenous Agroforestry Systems and Other Land Use in the upper Solimões Region, Western Amazonas State, Brazil

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Agricultural Sciences 2017年第7期8卷 657-674页

作者： Fernanda Tunes Villani gyovanni augusto aguiar ribeiro Ecila Mercês de Albuquerque Villani Wenceslau Geraldes Teixeira Fatima Maria de Souza Moreira Robert Miller Sonia Sena Alfaia Departamento de Química e Meio Ambiente Instituto Federal de Educa&#231 o Ciência e Tecnologia Manaus Brazil Universidade Federal de Viç osa Vi&#231 osa Brazil Departamento de Solos Embrapa Solos Empresa Brasileira de Pesquisa Agropecuária Rio de Janeiro Brazil. Departamento de Ciência do Solo Universidade Federal de Lavras Lavras Brazil United Nations Development Program Brasília Brazil Coordenaç o de Tecnologia e Inovaç o Instituto Nacional de Pesquisas da Amaz&#212 nia Manaus Brazil

Slash and burn cultivation systems carried out by many farmers in the Amazon region lead to changes in biogeochemical cycles of nutrients. To assess the extent of the impact of shifting cultivation on the soil in a floodplain portion of this region, samples of an Inceptisol surface layer (0 - 5 cm) under primary forest (FP), secondary forest at an advanced stage of recovery (FS), secondary forest at an initial stage of recovery (CAP), agroforestry (SAF), plantations (R?) in indigenous communities and small farmers, and pasture (PAS) in the Upper Solim?es region, Amazonas, were subjected to analysis of chemical composition during the wet (May) and dry (October) seasons, 2007. Soils were fertile with levels of P, K, Ca and Mg above those generally found in Amazon soils. Microbial content did not vary significantly in the systems studied in the wet season, but there was a reduction of around 60% with the change of season, except for soils with SAF. Ammonium nitrogen was predominant in all systems and seasons studied. Nitrate content was higher in R? soil, in two seasons, and lower in PAS. The type of management adopted by farmers in the region’s indigenous agroforestry systems resulted in small changes in P, K, Mg, MBC and mineral-N levels, independent of soil moisture.

关键词： Traditional Agriculture Soil Management Primary and Secondary Forests Pasture Inceptisol

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Past,present and future of the Resonant-Mass gravitational wave detectors

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Research in Astronomy and Astrophysics 2011年第1期11卷 1-42页

作者： Odylio Denys aguiar Instituto Nacional de Pesquisas Espaciais Divisao de Astrofísica Av. dos Astronautas 1758 So José dos Campos 12227-010 SP Brazil

Resonant-mass gravitational wave detectors are reviewed from the concept of gravitational waves and its mathematical derivation, using Einstein＇s general relativity, to the present status of bars and spherical detectors, and their prospects for the future, which include dual detectors and spheres with non-resonant transducers. The review not only covers technical aspects of detectors and sciences that will be done, but also analyzes the subject in a historical perspective, covering the various detection efforts over four decades, starting from Weber＇s pioneering work.

关键词： gravitation -- gravitational waves -- instrumentation: detectors

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Determination of Hypoxanthine in the Presence of Copper by Adsorptive Stripping Voltammetry

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American Journal of Analytical Chemistry 2014年第5期5卷 291-300页

作者： Percio augusto Mardini Farias Arnaldo aguiar Castro Department of Chemistry Pontifícia Universidade Católica Rua Marquês de S&atilde o Vicente Rio de Janeiro Brazil Facultad Quimica Quimica Analitica Universidad de La Habana Havana Cuba

A stripping method for the determination of hypoxanthine in the presence of copper at the submicromolar concentration levels is described. The method is based on controlled adsorptive accumulation of hypoxanthine-copper at the thin-film mercury electrode followed by a fast linear scan voltammetric measurement of the surface species. Optimum experimental conditions were found to be the use of 1.0 × 10﹣3 mol·L﹣1 NaOH solution as electrolyte supporting, an accumulation potential of ﹣0.50 V and a linear scan rate of 200 mV·s﹣1. The response of hypoxanthine-copper is linear over the concentration ranges of 10 - 60 ppb. For an accumulation time of 30 minutes, the detection limit was found to be 250 ppt (1.8 × 10﹣9 mol·L﹣1). Adequate conditions for measuring the hypoxanthine in the presence of metal ions, xanthine, uric acid and other nitrogenated bases were also investigated. The utility of the method is demonstrated by the presence of hypoxanthine associated in ATP or ssDNA.

关键词： Hypoxanthine Determination Xanthine Uric Acid Copper Ion ATP ssDNA Thin-Film Mercury Electrode Fast Linear Scan Stripping Voltammetry

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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

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Genotype-environment interaction in Cordia trichotoma(Vell.)Arrá*** *** in two different soil conditions

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Journal of Forestry Research 2022年第1期33卷 309-319页

作者： Wanderley dos Santos Bruno Marchetti de Souza Daniele Fernanda Zulian Gilberto Terra ribeiro Alves João Bosco Vasconcellos Gomes Mário Luiz Teixeira de Moraes Valderês Aparecida de Sousa Ananda Virginia de aguiar Faculdade de Engenharia de Ilha Solteira Universidade Estadual Paulista“Júlio Mesquita Filho”Ilha Solteira 15385-000Brazil Sucupira Agroflorestas Fazenda SucupiraValença 45400-000Brazil EMBRAPA Florestas Empresa Brasileira de Pesquisa AgropecuáriaColombo 83411-000Brazil

Investment in silvicultural techniques is noticeably lacking,especially in breeding programs for non-conventional wood *** genotype×environment interaction(G×E)is essential to the development of breeding ***,this study aimed to estimate genetic diversity of and the effects of G×E interaction on two progeny tests of Cordia trichotoma,including the estimation of genetic gain and genetic diversity after *** the experiment,30 progenies of *** were tested at two sites with differing soil *** at breast height(1.30 m above soil surface,dbh-cm),total height,diameter at 30 cm from the soil,first branch height,and survival were all monitored for four *** deviance,best linear unbiased estimator,and harmonic mean of relative performance of genetic values(MHPRVG)were all calculated to predict breeding values,estimate genetic parameters,and analyze *** quantified traits varied significantly among progenies by soil type,with greatest variation recorded for genetic *** of the progenies led to predictions of genetic gain,ranging from 7.73 to 15.45%,for dbh at four years of *** calculated decrease in genetic diversity after selection showed that this parameter should be monitored in subsequent breeding cycles.G×E was low for all *** best-performing progenies proved most stable and best adapted to the different environmental conditions tested.

关键词： Effective population number Native species Productivity Stability and adaptability Tree improvement

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Prognosis of forest production using machine learning techniques

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Information Processing in Agriculture 2023年第1期10卷 71-84页

作者： Jeferson Pereira Martins Silva Mayra Luiza Marques da Silva Adriano ribeiro de Mendonca Gilson Fernandes da Silva Antoˆnio Almeida de Barros Junior Evandro Ferreira da Silva Marcelo Otone aguiar Jeangelis Silva Santos Nı´vea Maria Mafra Rodrigues Federal University of Espirito Santo UFESDepartment of Forestry and Wood ScienceAvenue Governor Lindemberg31629550-000 Jeroˆnimo MonteiroESBrasil b Departamento de Cieˆncias Agra´riasUniversidade Federal de Sa o Joa del-Rei Sete Lagoas CampusHighway MG 424-Km 47Sete LagoasMinas Gerais 35701-970Brazil Federal University of Para(UFPA) University Campus of AltamiraStreet Cel.Jose Porfırio2515Sa o Sebastiao68372-040 AltamiraPABrazil

Forest production and growth are obtained from statistical models that allow the generation of information at the tree or forest stand *** the use of regression models is common in forest measurement,there is a constant search for estimation procedures that provide greater ***,machine learning techniques have been used with satisfactory performance in measuring ***,methods such as Adaptive NeuroFuzzy Inference System(ANFIS)and Random Forest are relatively poorly studied for predicting the volume of wood in eucalyptus plantations in ***,it is essential to check whether these techniques can provide gains in terms of ***,this study aimed to evaluate the use of Random Forest and ANFIS techniques in the prognosis of forest *** data used come from continuous forest inventories carried out in stands of eucalyptus *** data were divided into 70%for training and 30%for *** algorithms used to generate rules in ANFIS were Subtractive Clustering and ***,training was done with the hybrid algorithm(descending gradient and least squares)with the number of seasons ranging from 1 to *** RFs were trained,varying the number of trees from 50 to 850 and the number of observations by five leaves to *** neural networks and decision trees were also trained to compare the feasibility of the *** evaluation of the estimates generated by the techniques for training and validation was calculated based on the following statistics:correlation coefficient(r),relative Bias(RB),and the relative root mean square error(RRMSE)in *** general,the techniques studied in this work showed excellent performance for the training and validation data set with RRMSE values*** RF presented inferior statistics about the ANFIS for the prognosis of forest *** Subtractive Clustering(SC)and Fuzzy-C-Means(FCM)algorithms provide accurate baseline

关键词： Artificial Intelligence Ensemble Learning Forest Measurement Forest inventory Artificial Neural Networks Regression

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RNAi mechanisms in Huntington’s disease therapy:siRNA versus shRNA

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Translational Neurodegeneration 2017年第1期6卷 300-309页

作者： Sebastian aguiar Bram van der Gaag Francesco Albert Bosco Cortese Molecular Neuroscience Laboratory Swammerdam Institute for Life Sciences(SILS-CNS)University of AmsterdamAmsterdamNetherlands Fulbright Program US Department of State(IIE)New York CityNYUSA Department of Neurobiology Care Sciences and SocietyKarolinska InstituteStockholmSweden Biogerontology Research Foundation(BGRF) OxfordUK Department of Biomedical and Molecular Sciences Queen’s University School of MedicineQueen’s UniversityKingstonCanada

Huntington’s Disease(HD)is a genetically dominant trinucleotide repeat disorder resulting from CAG repeats within the Huntingtin(HTT)gene exceeding a normal range(>36 CAGs).Symptoms of the disease manifest in middle age and include chorea,dystonia,and cognitive *** latency from diagnosis to death is 20 *** are currently no disease-modifying therapies available to HD *** is a potentially curative therapy for HD.A popular line of research employs siRNA or antisense oligonucleotides(ASO)to knock down mutant Huntingtin mRNA(mHTT).Unfortunately,this modality requires repeated dosing,commonly exhibit off target effects(OTEs),and exert renal and hepatic *** contrast,a single AAV-mediated short-hairpin RNA(shRNA)dose can last years with low *** addition,we highlight research indicating that shRNA elicits fewer OTEs than siRNA when tested *** this promise,shRNA therapy has been held back by difficulties controlling expression(oversaturating cells with toxic levels of RNA construct).In this review,we compare RNAi modalities for HD and propose novel methods of optimizing shRNA expression and on-target fidelity.

关键词： RNAi shRNA siRNA Huntington’s disease Off-target effects Huntingtin Silencing

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A Review of Recent Advances in Hybrid Natural Fiber Reinforced Polymer Composites

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Journal of Renewable Materials 2022年第3期10卷 561-589页

作者： Jorge Neto Henrique Queiroz Ricardo aguiar Rosemere Lima Daniel Cavalcanti Mariana Doina Banea Federal Centre of Technological Education in Rio de Janeiro(CEFET/RJ) Rio de JaneiroBrazil

Natural fiber reinforced polymer composites(NFRCs)have demonstrated great potential for many different applications in various industries due to their advantages compared to synthetic fiber-reinforced composites,such as low environmental impact and low ***,one of the drawbacks is that the NFRCs present relatively low mechanical properties and the absorption of humidity due to the hydrophilic characteristic of the natural *** method to increase their performance is ***,understanding the properties and potential of using multiple reinforcement’s materials to develop hybrid composites is of great *** paper provides an overview of the recent advances in hybrid natural fiber reinforced polymer ***,the main factors that affect the performance of hybrid fiber-reinforced composites were briefly *** effect of hybridization on the mechanical and thermal properties of hybrid composites reinforced with several types of natural fibers(i.e.,sisal,jute,curauá,ramie,banana,etc.)or natural fibers combined with synthetic fibers is ***,the water absorption behaviour of hybrid fiber-reinforced composites is also *** was con-cluded that the main challenges that need to be addressed in order to increase the use of natural-natural or natural-synthetic hybrid composites in industry are the poor adhesion between natural fibers and matrix,thermal stability and moisture absorption of natural *** of these challenges were addressed by recent develop-ment in fibers treatment and modification,and product innovation(hybridization).

关键词： Natural fiber composites(NFC) hybrid composites mechanical properties thermal properties water absorption

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Impact of train speed on the mechanical behaviours of track-bed materials

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第5期9卷 818-829页

作者： Francisco Lamas-Lopez Yu-Jun Cui Nicolas Calon Sofia Costa D’aguiar Tongwei Zhang Laboratoire Navier/CERMES Ecole des Ponts ParisTech Marne-la-Vallée 77455 France Département Ligne Voie et Environnement SNCF-Engineering La Plaine St. Denis 93574 France Division Auscultation Modélisation & Mesures SNCF-Research & Development Paris 75012 France

For the 30,000 km long French conventional railway lines(94% of the whole network),the train speed is currently limited to 220 km/h,whilst the speed is 320 km/h for the 1800 km long high-speed ***,there is a growing need to improve the services by increasing the speed limit for the conventional *** paper aims at studying the influence of train speed on the mechanical behaviours of track-bed materials based on field monitoring *** is put on the behaviours of interlayer and subgrade *** selected experimental site is located in Vierzon,*** sensors including accelerometers and soil pressure gauges were installed at different *** vertical strains of different layers can be obtained by integrating the records of accelerometers installed at different trackbed *** experimentation was carried out using an intercity test train running at different speeds from 60 km/h to 200 km/*** test train was composed of a locomotive(22.5 Mg/axle) and 7 'Corail'coaches(10.5 Mg/axle).It was observed that when the train speed was raised,the loadings transmitted to the track-bed ***,the response of the track-bed materials was amplified by the speed rise at different depths:the vertical dynamic stress was increased by about 10% when the train speed was raised from 60 km/h to 200 km/h for the locomotive loading,and the vertical strains doubled their quasistatic values in the shallow ***,the stressestrain paths were estimated using the vertical stress and strain for each train *** loading paths allowed the resilient modulus Mrto be *** was found that the resilient modulus(M_r) was decreased by about 10% when the train speed was increased from 100 km/h to 200 km/***,the damping ratio(D_r) kept stable in the range of speeds explored.

关键词： Field experimentation Conventional track-bed materials Train speed upgrade Mechanical behaviours Reversible modulus Damping ratio

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Terpenes extracted from marine sponges with antioxidant activity:a systematic review

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Natural Products and Bioprospecting 2023年第1期13卷 516-527页

作者： Cintia Cristina Santi Martignago Beatriz Soares-Silva Julia Risso Parisi Lais Caroline Souza e Silva Renata Neves Granito Alessandra Mussi ribeiro Ana Cláudia Muniz Renno Lorena Ramos Freitas de Sousa Anna Caroline Campos aguiar Departamento de Biociências Universidade Federal de São Paulo(UNIFESP)Rua Silva Jardim 136Edifício CentralSantosSP 11015-020Brazil Institute of Chemistry Federal University of Catalão(UFCAT)Av.Dr.Lamartine Pinto de Avelar1120 Vila ChaudCatalãoGO 75704-020Brazil

Marine biodiversity has emerged as a very promising resource of bioactive compounds and secondary metabolites from different sea *** sponge’s secondary metabolites demonstrated various bioactivities and potential pharmacological *** systematic review of the literature focuses on the advances achieved in the antioxidant potential of marine sponges in *** review was performed in accordance with PRISMA *** main inclusion criterion for analysis was articles with identification of compounds from terpene classes that demonstrate antioxidant activity in *** in three different databases,two hundred articles were *** screening abstracts,titles and evaluating for eligibility of manuscripts 14 articles were *** most performed analyzes to detect antioxidant activity were scavenging activity 2,2-diphenyl-1-picrylhydrazyl(DPPH)and measurement of intracellular reactive oxygen species(ROS).It was possible to identify 17 compounds of the terpene class with pronounced antioxidant activity in *** evidence of the studies included in this review was accessed by the GRADE *** play an important ecological role,moreover these molecules have a pharmaceutical and industrial application.

关键词： Antioxidant Marine drugs Sponge Free radical

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