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Different no-till grain production systems with Urochloa *** soil microbial community structure,biomass and activity in a tropical Ultisol

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Soil Ecology Letters 2024年第1期6卷 119-129页

作者： Matheus Emannuel Oliveira Vieira Lucas Dantas lopes France Mario Costa Viviane Talamini Edson Patto Pacheco Marcelo Ferreira Fernandes PPGAGRI Universidade Federal de SergipeAv.Marechal Rondons/n-49100-000-Sao CristovaoSEBrazil Embrapa Coastal Tablelands Av Govemador Paulo Barreto de Menezesn°3250-49025-040-AracajuSEBrazil

Integrated grain cropping systems promote soil health(SH)and *** biomass and activity(MBA)and community structure(MCS)are key to *** of maize with Urochloa pastures strongly impacts MBA and *** is more sensitive than MCS to shifts in grain cropping *** under continuous Urochloa increased microbial activity and AMF *** soils are prone to *** of conservation agricultural practices is essential to improve soil health,which is influenced by soil *** this study we analyzed shifts in microbial biomass and activity(MBA)and microbial community structure(MCS)based on fatty acid methyl esthers(FAMEs)between five no-till agricultural practices:maize monoculture(MM);maize annualy intercropped with Urochloa decumbens(M/Ud);M/Ud with soybean rotation every other year(M/Ud-S);M/Ud keeping the pasture for the next two years(M/Ud-Ud-Ud);and maize intercropped with *** keeping the pasture for the next two years(M/Ur-Ur-Ur).Results indicated that MBA was affected by the inclusion of Urochloa intercropping and by rotation with *** under a longer residence time with Urochloa in the field had higherβ-glucosidase activity and soil basal respiration,indicating a greater microbial *** was less affected than MBA by the investigated cropping *** changed only in the continuous pasture systems,which were enriched in arbuscular mycorrhyzal fungi(AMF).Additionally,the continuous pasture systems had lower microbial stress ratios than the other agricultural *** sum,our study showed that utilization of Urochloa *** longer periods in no-till agricultural practices contributes to increase microbial activity,AMF abundance and decrease microbial stress *** changes are primarily beneficial for soil health.

关键词： crop-pasture integration crop rotation no-tillage soil health microbial ecology

Synthesis of coral-like structures of Pr-Yb co-doped YIG: Structural,optical, magnetic and antimicrobial properties

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Journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.Guerra S.Castro-lopes J.Matilla-Arias Idglan S.de Lima Edson C.Silva-Filho Josy A.Osajima F.Guerrero R.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. Structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDS) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against S. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

Evaluation of the regional distribution of the pediatric surgery workforce and surgical load in Brazil

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World Journal of Pediatric Surgery 2023年第2期6卷 85-91页

作者： joaquim Bustorff-Silva Marcio lopes Miranda Amanda Rosendo Ayla Gerk Antonio Goncalves Oliveira-filho Pediatric Surgery State University of Campinas Medical SchoolCampinasBrazilPediatric SurgeryState University of Campinas Medical SchoolCampinasBrazil Medicine Pontificia Universidad Católica ArgentinaBuenos AiresArgentina

Objective The purpose of this study is to examine the regional distribution of the pediatric surgery workforce and the expected local demand for pediatric surgical procedures in *** We collected data on the pediatric surgical workforce,surgical volume,Gross Domestic Product per capita,and mortality for gastrointestinal tract malformations(MGITM)across the different regions of Brazil for *** Data from the Federal Medical Council reported 1515 pediatric surgery registries in Brazil,corresponding to 1414 pediatric surgeons(some pediatric surgeons are registered in more than one state),or 2.4 pediatric surgeons per 100000 children 14 years of age and *** were 828 men and 586 *** mean age was 51.5±12.8 years,and the mean time from graduation was 3.4±5.7 *** is a higher concentration of pediatric surgeons in the wealthier Central-West,South,and Southeast *** surgical volume ranged from 88 to 245 operations/year(average 146 operations/year)depending on the *** these,only nine(6.1%)were high-complexity(including neonatal)*** tended to be higher in the poorer north and northeast regions than in other regions of *** Our findings suggest significant disparities in the surgical workforce and workload across Brazil related to socioeconomic *** with an increased surgical workforce were associated with lower *** average number of complex operations performed annually by each pediatric surgeon was considerably *** investment and well-defined health policies are imperative to enhance the quality of surgical care in the different regions of Brazil.

关键词： pediatric operations distribution

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碟式离心机分离性能试验及数值模拟研究

天津大学学报（自然科学与工程技术版） 2023年第6期56卷 579-587页

作者：朱国瑞郝泽基吴将天 Pinto lopes Maia Junior joaquim 谭蔚天津大学化工学院天津300350 天津大学浙江研究院宁波315201 浙江轻机实业有限公司杭州311401

碟式离心机作为高效分离机械广泛应用于食品、化工、制药等行业生产.为探究碟式离心机的内部流场及分离效率,进行了现场试验,并根据Σ理论建立了具有20层碟片的简化三维物理模型,利用FLUEnT软件对转鼓内的流场及分离过程进行数值模拟.... 详细信息

碟式离心机作为高效分离机械广泛应用于食品、化工、制药等行业生产.为探究碟式离心机的内部流场及分离效率,进行了现场试验,并根据Σ理论建立了具有20层碟片的简化三维物理模型,利用FLUEnT软件对转鼓内的流场及分离过程进行数值模拟.试验结果表明,转速和进料量对碟式离心机分离效率影响较大,提高转速、降低进料量均能提高离心机的分离效率,通过分析进出口物料的粒径发现,在试验工况下,粒径大于6μm的颗粒均能被有效分离,改变操作参数主要影响粒径为2~5μm的颗粒的分离.模拟结果表明:在碟片间隙内,物料对碟片的跟随性良好,压力与半径呈现出二次型正比关系,周向速度与半径成正比关系,在沉渣区域物料明显滞后于转鼓转动,这导致离心液压和周向速度均小于理论值,同时随着转速的提高,沉渣区域物料的滞后性更加明显;由于上升通道存在,在碟片间隙内局部位置存在明显轴向速度,从而对碟片内的流动产生干扰,导致碟片大端位置的周向速度和离心液压分布不均;在两相分离过程中,颗粒自液相中分离,沉积于上碟片的下表面,并滑落至转鼓沉渣区,固相颗粒在碟片间隙内主要堆积于定距条前侧,在相邻两个定距条之间,固相体积分数沿顺时针方向减少.研究方法与结果为碟式离心机分离性能模拟计算提供了参考,对碟式离心机的设计与结构优化提供了数据指导.

关键词：碟式离心机离心沉降数值模拟固液两相分离

Formation and Evolution of Wakes in the Spacetime Generated by a Cosmic String in <i>f</i>(<i>R</i>) Theory of Gravity

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Journal of High Energy Physics, Gravitation and Cosmology 2022年第1期8卷 85-96页

作者： Gabriela Coutinho de Carvalho Maria Emília Xavier Guimarães Pablo Oliveira Mesquita joaquim lopes.n.to Universidade Estadual do Rio de Janeiro Faculdade de Tecnologia Resende Brazil Instituto de Física Universidade Federal Fluminense Av. Litoranea S/N Niterói Brazil Instituto de Fsica Universidade Federal do Rio de Janeiro—UFRJ Av. Athos da Silveira Ramos Cidade Universitária Rio de Janeiro Brazil

The formation and evolution of cosmic string wakes in the framework of a f(R) theory of gravity are investigated in this work. We consider a simple model in which baryonic matter flows past a cosmic string. We treat this problem in the Zel’dovich approximation. We compare our results with previous results obtained in the context of General Relativity and Scalar-Theories of Gravity.

关键词： Topological Defects Alternative Theories of Gravity Structure Formation in the Universe

Plant-based pecan nut cake beverage enrichment of phytochemicals and antioxidant properties using multi-stage block freeze concentration

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Food Production, Processing and nutrition 2022年第1期4卷 433-446页

作者： Laércio Galvão Maciel Gerson lopes Teixeira Department of Food Science and Technology Federal University of Santa Catarina88034-001 FlorianópolisSCBrazil

Pecan nut (Carya illinoinensis) processing to obtain oil generates circa 37% of press cake, which is currently underuti-lized and primarily employed as animal feed. Due to its nutritional- and bioactive-rich composition, pecan nut cake (PnC) can be used as raw material for plant-based beverages, whose properties may be enhanced using a non-ther-mal technology based on block freeze concentration (BFC). The effect of five-stage BFC on total solids content (TSC), pH, color parameters, retention of phytochemicals, and the antioxidant activity (AA) of a pecan nut cake beverage (PnB) was assessed in this work. BFC afforded 98% (w/w) solids retention after three stages and 85% efficiency after four stages. The process also provided a 254% concentration factor in stage 5. In the last step, approximately a 64% increase in TSC and a slight decrease (7.3%) in pH compared to the control PnB was observed. In addition, total phenolic compounds, condensed tannins, total flavonols, and AA were significantly (P ng in a 2.6-10.2- and 1.9-5.8-fold increase in phytochemicals and antioxidants, respectively. On the other hand, BFC caused the darkening of concentrates due to TSC and bioactive compounds retention. The processing strategy evaluated herein indicated a great potential of PnC as a raw material for obtaining high-quality ingredients for the food industry, which may reduce agro-industrial waste production and add value to a coproduct rich in nutrients and biocompounds with potential biological activity.

关键词： Caryaillinoinensis Press cake Waste valorization Plant-based beverage Bioactive compounds Cryoconcentration

Layered double hydroxide(LDH)-based materials:A mini-review on strategies to improve the performance for photocatalytic water splitting

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Journal of Energy Chemistry 2022年第1期31卷 406-431,I0011页

作者： Hanane Boumeriame Eliana S.Da Silva Alexey S.Cherevan Tarik Chafik joaquim L.Faria Dominik Eder Laboratory of Separation and Reaction Engineering-Laboratory of Catalysis and Materials(LSRE-LCM) Faculdade de EngenhariaUniversidade do PortoRua Dr Roberto Frias s/n4200-465 PortoPortugal Institute of Materials Chemistry Technische Universicat Wien(TU Wien)Getreidemarkt 9Vienna 1060Austria Laboratory of Chemical Engineering and Valorization of Resources(LGCVR-UAE/L01FST).Faculte des Sciences et Techniques Universite Abdelmalek EssaadiTangierMorocco

The high energy demand we currently face in society and the subsequent large consumption of fossil fuels cause its depletion and increase the pollution *** quest for the production of clean energy from renewable and sustainable sources remains *** conversion of solar energy into hydrogen via the water-splitting process,assisted by pho tores pons ive semiconductor catalysts,is one of the most promising *** progress has been made on water splitting in the past few years and a variety of photocatalysts active not only under ultra-violet(UV) light but especially with the visible part of the electromagnetic spectrum have been *** double hydroxides(LDH)-based materials have emerged as a promising class of nanomaterials for solar energy applications owing to their unique layered structure,compositional flexibility,tunable bandgaps,ease of synthesis and low manufacturing *** review covers the most recent research dedicated to LDH materials for photocatalytic water-splitting applications and encompasses a range of synthetic strategies and post-modifications used to enhance their ***,we provide a thorough discussion of the experimental conditions crucial to obtaining improved photoactivity and highlight the impact of some specific parameters,namely,catalysts loading,cocatalysts,sacrificial agents,and irradiation *** review provides the necessary tools to select the election technique for adequately enhancing the photoactivity of LDH and modified LDH-based materials and concludes with a critical summary that outlines further research directions.

关键词： Layered double hydroxides Water splitting Photocatalysis Hydrogen generation Oxygen evolution nanomaterials

Explicit bivariate rate functions for large deviations in AR(1)and MA(1)processes with Gaussian innovations

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Probability, Uncertainty and Quantitative Risk 2023年第2期8卷 177-212页

作者： Maicon J.Karling Artur O.lopes Sílvia R.C.lopes Mathematics and Statistics Institute Federal University of Rio Grande do Sul91500-900 Porto AlegreRSBrazil

We investigate the large deviations properties for centered stationary AR(1)and MA(1)processes with independent Gaussian innovations,by giving the explicit bivariate rate functions for the sequence of two-dimensional random *** the Contraction Principle,we provide the explicit rate functions for the sample mean and the sample second *** the AR(1)case,we also give the explicit rate function for the sequence of two-dimensional random vectors(W_(n))n≥2=(n^(-1(∑_(k=1)^(n)X_(k),∑_(k=1)^(n)X_(k)^(2))))_(n∈n)n≥2,but we obtain an analytic rate function that gives different values for the upper and lower bounds,depending on the evaluated set and its intersection with the respective set of exposed points.A careful analysis of the properties of a certain family of Toeplitz matrices is *** large deviations properties of three particular sequences of one-dimensional random variables will follow after we show how to apply a weaker version of the Contraction Principle for our setting,providing new proofs for two already known results on the explicit deviation function for the sample second moment and Yule-Walker *** exhibit the properties of the large deviations of the first-order empirical autocovariance,its explicit deviation function and this is also a new result.

关键词： Autoregressive processes Empirical autocovariance Large deviations Moving average processes Sample moments Toeplitz matrices Yule-Walker estimator

Parameter estimation in Manneville–Pomeau processes

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Probability, Uncertainty and Quantitative Risk 2023年第2期8卷 213-234页

作者： Barbara P.Olbermann Sílvia R.C.lopes Artur O.lopes Faculdade de Matemática-PUCRS 90650-002 Porto AlegreRSBrazil Instituto de Matemática e Estatística-UFRGS 91500-900 Porto AlegreRSBrazil

In this paper,we study a class of stochastic processes{X_(t)}t∈n,where X_(t)=φ■T_(s)^(t)(X_(0))is obtained from the iterations of the transformation T_(s),invariant for an ergodic probabilityμ_(s)on[0,1]and a certain constant by partial functionφ:[0,1]→*** consider here the family of transformations T_(s):[0,1]→[0,1]indexed by a parameters>0,known as the Manneville–Pomeau family of *** autocorrelation function of the resulting process decays hyperbolically(or polynomially)and we obtain efficient methods to estimate the parameter s from a finite time *** a consequence,we also estimate the rate of convergence of the autocorrelation decay of these *** compare different estimation methods based on the periodogram function,the smoothed periodogram function,the variance of the partial sum,and the wavelet *** obtain our results we analyzed the properties of the spectral density function and the associated Fourier series.

关键词： Manneville–Pomeau maps Long and not so long dependence Estimation Autocorrelation decay Spectral density function