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Frontiers of Mechanical engineering 2015年第3期10卷 287-293页

作者： Jonnathan D. sANTOs Jorge I. FAJARDO Alvaro R. CUJI Jaime A. GARCIA luis e. GARZON luis M. LOPeZ Department of Mechanical engineering Universidad Polit6cnicaSalesiana Elia Liut Ecuador Department of Mechanical engineering Universidad PontificiaBolivariana Medellin Columbia

A polymeric natural fiber-reinforced composite is developed by extrusion and injection molding process. The shrinkage and warpage of high-density polyethylene reinforced with short natural fibers of Guadua angustifolia Kunth are analyzed by experimental measure- ments and computer simulations. Autodesk Moldflow and solid Works are employed to simulate both volumetric shrinkage and warpage of injected parts at different configurations： 0wt.%, 20wt.%, 30wt.% and 40 wt.% reinforcing on shrinkage and warpage behavior of polymer composite. Become evident the restrictive effect of reinforcing on the volumetric shrinkage and warpage of injected parts. The results indicate that volumetric shrinkage of natural composite is reduced up to 58% with fiber increasing, whereas the warpage shows a reduction form 79% to 86% with major fiber content. These results suggest that it is a highly beneficial use of natural fibers to improve the assembly properties of polymeric natural fiber-reinforced composites.

关键词： biocomposite natural fiber shrinkage,simulation warpage

Biological treatments as a mean to improve feed utilization in agriculture animals——An overview

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Journal of Integrative Agriculture 2015年第3期14卷 534-543页

作者： Nahla A Abdel-Aziz Abdelfattah Z M salem Mounir M el-Adawy luis M Camacho Ahmed e Kholif Mona M Y elghandour Borhami e Borhami Department of Animal and Fish Production Faculty of Agriculture Alexandria University Faculty of Veterinary Medicine and Animal science Autonomous University of the State of Mexico Dairy science Department National Research Centre Faculty of Veterinary and Livestock Autonomous University of Guerrero

As a result of agriculture practices, million tons of agriculture are produced as a secondary or by-products; however, with low nutritive values. Many methods are applied to improve the nutritive value and increase its utilization in ruminant＇s nutrition. The biological treatments are the most common with more safe-treated products. In most cases, the biological treatments are paralleled with decreased crude fiber and fiber fractions content with increased crude protein content. Direct-fed microbial and exogenous enzymes to animal are other ways of biological methods for improving nutritive value of feeds. Here in this review, we will try to cover the biological treatments of by-products from different sides view with different types of animals and different animal end-products.

关键词： biological treatment by-products nutrition nutritive values

Glyphosate Dissipation in Different soils Under No-Till and Conventional Tillage

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Pedosphere 2019年第6期29卷 773-783页

作者： elena OKADA Joséluis COsTA Francisco BeDMAR Consejo Nacional de Investigaciones Científicas y Técnicas(CONICeT) Balcarce 7620(Argentina estación experimental Agropecuaria Balcarce Instituto Nacional de Tecnología Agropecuaria(INTA)Balcarce 7620(Argentina Facultad de Ciencias Agrarias Universidad Nacional de Mar del PlataBalcarce 7620(Argentina

Glyphosate is the most used herbicide in Argentina, accounting for 62% of the commercialized pesticides on the market. It is used as a weed controller in no-till systems, and it is also applied to various genetically modified crops ( e.g., soybean, corn, and cotton). Although it has a high solubility in water, it tends to adsorb and accumulate in agricultural soils. The main objectives of this work were to compare the dissipation of glyphosate and the accumulation of its metabolite aminomethylphosphonic acid (AMPA) over time in three soils from agricultural areas of Argentina under long-term management with no-till (NT) and conventional tillage (CT) practices. There were no differences in dissipation between NT and CT, indicating that the glyphosate-degrading microflora was not modified by the different tillage managements. Moreover, tillage practices did not alter the general soil properties;therefore, glyphosate bioavailability was not affected by NT or CT practice. Forty percent of the applied glyphosate was degraded within the first three days in all soils, indicating a fast initial dissipation rate. However, the dissipation rate considerably decreased over time, and the degradation kinetics followed a bi-exponential (or two-compartment) kinetic model. No differences were found between tillage practices. Dissipation was not related to the microbial activity measured as soil respiration. The fast decrease in the concentration of glyphosate at the beginning of the dissipation study was not reflected in an increase in the concentration of AMPA. The estimated half-lives for glyphosate ranged between 9 and 38 d. However, glyphosate bioavailability decreases over time, as it is strongly adsorbed to the soil matrix. This increases its residence time, which may lead to its accumulation in agricultural soils.

关键词： Aminomethylphosphonic acid Bioavailability Biodegradation Herbicide Metabolite Pesticide Two-compartment kinetic model

symmetrization for Fractional elliptic and Parabolic equations and an Isoperimetric Application(Dedicated to Haim Brezis,great master of analysis,on his 70th birthday)

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Chinese Annals of Mathematics,series B 2017年第2期38卷 661-686页

作者： Yannick sIRe Juan luis VAZQUeZ Bruno VOLZONe johns hopkins university Krieger Hall3401 N.Charles StBaltimoreM D21218USA. departamento de matemticas universidad autnoma de madrid28049 M adridSpain dipartimento di ingegneria universit degli studi di napoli"parthenope"80143 Italia.

This paper develops further the theory of symmetrization of fractional Laplacian operators contained in recent works of two of the authors. This theory leads to optimal estimates in the form of concentration comparison inequalities for both elliptic and parabolic equations. The authors extend the theory for the so-called restricted fractional Laplacian defined on a bounded domain Ω of R^N with zero Dirichlet conditions outside of Ω. As an application, an original proof of the corresponding fractional Faber-Krahn inequality is derived. A more classical variational proof of the inequality is also provided.

关键词： symmetrization, Fractional Laplacian, Nonlocal elliptic and parabolicequations, Faber-Krahn inequality

expression of an endoglucanase from Tribolium castaneum （TceG 1 ） in saccharomyces cerevisiae

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Insect science 2014年第5期21卷 609-618页

作者： Derek shirley Cris Oppert Todd B. Reynolds Bethany Miracle Brenda Oppert William e. Klingeman Juan luis Jurat-Fuentes Department of entomology and Plant Pathology University of Tennessee Department of Microbiology University of TennesseeKnoxville TN 37996 UsDA-Agricultural Research service Center for Grain and Animal Health Research Manhattan KS 66502 Department of Plant sciences University of Tennessee Knoxville TN 37996 USA

Insects are a largely unexploited resource in prospecting for novel cellulolytic enzymes to improve the production of ethanol fuel from lignocellulosic biomass. The cost of lignocellulosic ethanol production is expected to decrease by the combination of cellulose degradation （saccharification） and fermentation of the resulting glucose to ethanol in a single process, catalyzed by the yeast saccharomyces cerevisiae transformed to express efficient cellulases. While s. cerevisiae is an established heterologous expression system, there are no available data on the functional expression of insect cellulolytic enzymes for this species. To address this knowledge gap, s. cerevisiae was transformed to express the full-length cDNA encoding an endoglucanase from the red flour beetle, Tribolium castaneum （TceG 1）, and evaluated the activity of the transgenic product （rTceG 1）. expression of the TceG1 cDNA in s. cerevisiae was under control of the strong glyceraldehyde-3 phosphate dehydrogenase promoter. Cultured transformed yeast secreted rTceG1 protein as a functional β-1,4-endoglucanase, which allowed transformants to survive on selective media containing cellulose as the only available carbon source. evaluation of substrate specificity for secreted rTceG1 demonstrated endoglucanase activity, although some activity was also detected against complex cellulose substrates. Potentially relevant to uses in biofuel production rTceG1 activity increased with pH conditions, with the highest activity detected at pH 12. Our results demonstrate the potential for functional production of an insect cellulase in s. cerevisiae and confirm the stability of rTceG1 activity in strong alkaline environments.

关键词： biofuels insect cellulase saccharomyces cerevisiae Tribolium castaneum yeast

Capillary hydrodynamic fractionation of hydrophobic colloids:errors in the estimated particle size distribution

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Particuology 2014年第6期12卷 97-105页

作者： luis A.Clementi Zohartze Artetxe Ziortza Aguirreurreta Amaia Agirre Jose R.Leiza luis M.Gugliotta Jorge R.Vega INTeC(CONICeT and Universidad Nacional del Litoral) FRsF-UTN(Facultad Regional santa Fe-Universidad Tecnologica Nacional) POLYMAT Kimika Aplikatua SailaKimika Zientzien FakultateaUniversity of the Basque Country UPV/EHUJoxe Mari Korta Zentroa

Capillary hydrodynamic fractionation（CHDF） with turbidity detection at a single wavelength is an analytical technique that is often used for sizing the sub-micrometric particles of hydrophobic *** article investigates three sources of errors that affect the particle size distribution（PsD） estimated by CHDF：diameter calibration errors,uncertainties in the particle refractive index（PRI）,and instrumental broadening（IB）.The study is based on simulated and experimental examples that involve unimodal and bimodal *** errors in the diameter calibration curve can produce important deviations in the number average diameter due to systematic shifts suffered by the PsD *** uncertainties in the PRI are unimportant in the analysis of unimodal PsDs,but in the specific case of bimodal PsDs,errors in the PRI can strongly affect the estimated number concentration of each *** typical IB correction（based on the IB function estimated from narrow standards） produces slightly erroneous average diameters but can lead to PsDs with underestimated widths and distorted *** practice,the three investigated sources of errors can be present simultaneously,and uncertainties in the average diameters,the shape and width of the PsD,and the number concentration of the PsD modes are unavoidable.

关键词： Particle size distribution Capillary hydrodynamic fractionation Nanoparticle Particle refractive index Instrumental broadening

Approximating home ranges of humpback and fin whales in Drake Passage and Antarctica

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Advances in Polar science 2020年第4期31卷 248-257页

作者： Joséluis ORGeIRA Facundo ALVAReZ Departamento Biología de los Predadores Tope Instituto Antártico Argentino.Buenos AiresArgentina Programa de pós-graduação em ecologia e Conservação.Campus de Nova Xavantina.Universidade do estado de Mato Grosso Brasil

Identifying home ranges—those areas traversed by individuals in their normal foraging,mating,and parenting activities—is an important aspect of cetacean *** these ranges facilitates identification of resource use and *** and humpback whales occur in Antarctica during the austral summer,but information regarding their home ranges is *** opportunistically collected whale sighting data from eight consecutive summer seasons spanning 2010–2017,we approximate the home ranges of humpback and fin whales around Drake Passage(DRA),West of Antarctic Peninsula(WAP),south shetland Islands(ssI),an area northwest of the Weddell sea(WeD),and around the south Orkney Islands(sOI).Approximate home ranges are identified using Kernel Density estimation(KDe).Most fin whales occurred north and northwest of the sOI,which suggests that waters near these islands support concentrations of this *** humpback whales were observed around the ssI,but unlike fin whales,their distributions were highly variable in other *** suggests spatial segregation in areas where both species exist such as sOI,ssI,and *** redundancy analysis(pRDA)suggests that the distributions of these species are more affected by spatial variables(latitude,longitude)than by local scale variables such as sea surface temperature and *** study presents a visual approximation of the home ranges of fin and humpback whales,and identifies variation in the effects of space and environmental variables on the distributions of these whales at different spatial scales.

关键词： humpback whale fin whale home range Antarctica Drake Passasge

Classification of low-density eeG for epileptic seizures by energy and fractal features based on eMD

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The Journal of Biomedical Research 2020年第3期34卷 180-190页

作者： luis Alfredo Moctezuma Marta Molinas Department of engineering Cybernetics Norwegian University of Science and TechnologyTrondheim 7434Norway

We are here to present a new method for the classification of epileptic seizures from electroencephalogram(eeG) *** consists of applying empirical mode decomposition(eMD) to extract the most relevant intrinsic mode functions(IMFs) and subsequent computation of the Teager and instantaneous energy,Higuchi and Petrosian fractal dimension,and detrended fluctuation analysis(DFA) for each *** validated the method using a public dataset of 24 subjects with eeG signals from 22 channels and showed that it is possible to classify the epileptic seizures,even with segments of six seconds and a smaller number of channels(e.g.,an accuracy of0.93 using five channels).We were able to create a general machine-learning-based model to detect epileptic seizures of new subjects using epileptic-seizure data from various subjects,after reducing the number of instances,based on the k-means algorithm.

关键词： epileptic seizure electroencephalograms empirical mode decomposition detrended fluctuation analysis energy distribution fractal dimension

Management of gallstones and gallbladder disease in patients undergoing gastric bypass

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World Journal of Gastroenterology 2010年第17期16卷 2075-2079页

作者： Bernabé M Quesada Gustavo Kohan Hernán e Roff Carlos M Canullán luis T Chiappetta Porras Department of surgery Cosme Argerich HospitalAlte.Brown 240ZC 1155 Buenos AiresArgentina

The appropriate management of gallstones and gallbladder disease in patients undergoing gastric bypass remains *** therapeutic modalities are used and include performing cholecystectomy on all patients at the time of gastric bypass,performing concomitant cholecystectomy only when patients have gallstones and performing cholecystectomy only in the presence of both symptoms and *** groups administer ursodeoxycholic acid for gallstone prevention in the postoperative *** treatment modalities are analyzed and their results and rationality are discussed.

关键词： Gallbladder Gastric bypass Morbid obesity Gallstones Cholecystectomy

Fragility Assessment of Pre-Northridge steel Moment Frames Using Finite-Length Plastic Hinge elements and Concentrated Plasticity Fracture elements

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Computer Modeling in engineering & sciences 2019年第9期120卷 657-676页

作者： Filipe L.A.Ribeiro Andre RBarbosa luis CNeves National Laboratory of Civil engineering(LNeC)&CeRIs-Civil engineering Research and Innovation for sustainability DECivilUniversity of LisbonLisbonPortugal school of Civil and Construction engineering Oregon State UniversityOregonUSA and University of BristolBristolUK Resilience engineering Research Group University of NottinghamNottinghamUK.

Although pre-Northridge earthquake steel moment resisting frame buildings have been shown to be susceptible to brittle connection failures,they still represent a large fraction of the existing steel buildings in the United states of *** this study,the performance of the 3-and 9-story Los Angeles pre-Northridge sAC buildings are analyzed considering ductile and brittle beam-column connection failures,and their *** paper contributes to understanding the influence of uncertainty associated with connections brittle fracture on building interstory deformation capacity and its impact on bias and variability of fragility functions and loss *** results show that considering brittle connections leads to significantly l arger d rift demands a nd t o h igher r epair costs,particularly under intense ground *** fragility curve parameters are derived that account for the effect of the uncertainty of the strength and deformation capacity of brittle connections.

关键词： Brittle fracture finite-length p lastic h inge f ragility c urves r epair c ost ratio welded-flange connections