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Compost Input Effect on Dryland Wheat and Forage Yields and Soil Quality

Pedosphere 2018年第3期28卷 451-462页

作者： Francisco j. calderon Merle F. VIGIL joseph BENjAMIN United States Department of Agriculture-Agricultural Research Service (USDA-ARS) Central Great Plains Research Station Akron80720 CO( USA)

Organic agricultural systems rely on organic amendments to achieve crop fertility requirements, and weed control must be achieved without synthetic herbicides. Our objective was to determine the crop yield and soil quality as affected by a transition from grass to dryland organic agriculture in the Central Great Plains of North America. This study evaluated three beef feedlot compost(BFC)treatments in 2010–2015 following biennial application rates: 0(control), 22.9, and 108.7 t ha^(-1) on two dryland organic cropping systems: a wheat(Triticum aestivum)-fallow(WF) rotation harvested for grain and a triticale(Triticosecale)/pea(Pisum sativum)-fallow(T/P-F) rotation harvested for forage. The triticale + pea biomass responded positively to the 108.7-t ha^(-1) BFC treatment,but not the 22.9-t ha^(-1) BFC treatment. The wheat biomass was not affected by BFC addition, but biomass N content *** feedlot compost input did not increase wheat grain yields, but had a positive effect on wheat grain Zn content. Soil total C and N contents increased with the rate of 108.7 t ha^(-1) BFC after three applications, but not with 22.9 t ha^(-1) BFC. Soil enzyme activities associated with N and C cycling responded positively to the 108.7-t ha^(-1) BFC treatment. Saturated salts were high in the soil receiving 108.7 t ha^(-1) of BFC, but did not affect crop yields. These results showed that BFC was effective in enhancing forage yields, wheat grain quality, and soil C and N, as well as specific microbial enzymes important for nutrient cycling. However, the large rates of BFC necessary to elicit these positive responses did not increase grain yields, and resulted in an excessive buildup of soil P.

关键词： organic agriculture soil C soil enzyme activity soil N pea triticale

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On the Structure of Graded Leibniz Algebras

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Algebra Colloquium 2015年第1期22卷 83-96页

作者： Antonio j. calderon Martin jose M. Sfinchez Delgado Departamento de Matemdticas Universidad de Cadiz 11510 Puerto Real Cadiz Spain

We study the structure of graded Leibniz algebras with arbitrary dimension and over an arbitrary base field K. We show that any of such algebras ￡ with a symmetric G-support is of the form ￡ = U-∑jIj with U a subspace of ￡1, the homogeneous component associated to the unit element 1 in G, and any Ij a well described graded ideal of ￡, satisfying [Ij, Ik]= 0 if j≠ k. In the case of ￡ being of maximal length, we characterize the gr-simplicity of the algebra in terms of connections in the support of the grading.

关键词： graded Leibniz algebra infinite dimensional Leibniz algebra structure theory

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Particle shape characterisation and classification using automated microscopy and shape descriptors in batch manufacture of particulate solids

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Particuology 2016年第1期14卷 61-68页

作者： Yang Zhang jing j. Liu Lei Zhang jorge calderon De Anda Xue Z. Wang School of Chemistry and Chemical Engineering South China University of Technology 381 Wushan Road Guangzhou 510641 China School of Bioscience and Bioengineering South China University of Technology Guangzhou Higher Education Mega Centre Panyu District Guangzhou510006 China Institute of Particle Science and Engineering School of Chemical and Process Engineering University of Leeds Leeds I52 9JT UK

It is known that size alone, which is often defined as the volume-equivalent diameter, is not sufficient to characterize many particulate products. The shape of crystalline products can be as important as size in many applications, Traditionally, particulate shape is often defined by several simple descriptors such as the maximum length and the aspect ratio. Although these descriptors are intuitive, they result in a loss of information about the original shape. This paper presents a method to use principal component analysis to derive simple latent shape descriptors from microscope images of particulate products made in batch processes, and the use of these descriptors to identify batch-to-batch variations. Data from batch runs of both a laboratory crystalliser and an industrial crystallisation reactor are analysed using the described approach. Qualitative and quantitative comparisons with the use of traditional shape descriptors that have nhwical meanings and Fourier shape descriptors are also made.

关键词： Batch-to-batch variation Classification Principal components analysis Shape descriptors

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Cover Crop and Irrigation Effects on Soil Microbial Communities and Enzymes in Semiarid Agroecosystems of the Central Great Plains of North America

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Pedosphere 2016年第2期26卷 192-205页

作者： Francisco j. calderon David NIELSEN Veronica ACOSTA-MARTINEZ Merle F. VIGIL Drew LYON USDA-ARS Central Great Plains Research Station Akron CO 80720 USA USDA-ARS Cropping Systems Research Laboratory Wind Erosion and Water Conservation Unit Lubbock TX 79415 USA Department of Crop and Soil Sciences Washington State University Pullman WA 99164-6420 USA

Cover crops can have beneficial effects on soil microbiology by increasing carbon （C） supply, but these beneficial effects can be modulated by precipitation conditions. The objective of this study was to compare a fallow-winter wheat （Triticum aestivum L.） rotation to several cover crop-winter wheat rotations under rainfed and irrigated conditions in the semiarid US High Plains. Experiments were carried out at two sites, Sidney in Nebraska, and Akron in Colorado, USA, with three times of soil sampling in 2012--2013 at cover crop termination, wheat planting, and wheat maturity. The experiments included four single-species cover crops, a 10-species mixture, and a fallow treatment. The variables measured were soil C and nitrogen （N）, soil community structure by fatty acid methyl ester （FAME） profiles, and soil β-glucosidase,β-glucosaminidase, and phosphodiesterase activities. The fallow treatment, devoid of living plants, reduced the concentrations of most FAMEs at cover crop termination. The total FAME concentration was correlated with cover crop biomass （R = 0.62 at Sidney and 0.44 at Akron）. By the time of wheat planting, there was a beneficial effect of irrigation, which caused an increase in myeorrhizal and protozoan markers. At wheat maturity, the cover crop and irrigation effects on soil FAMEs had subsided, but irrigation had a positive effect on the β-glucosidase and phosphodiesterase activities at Akron, which was the drier of the two sites. Cover crops and irrigation were slow to impact soil C concentration. Our results show that cover crops had a short-lived effect on soil microbial communities in semiarid wheat-based rotations and irrigation could enhance soil enzyme activity. In the semiarid environment, longer time spans may have been needed to see beneficial effects of cover crops on soil microbial community structure, soil enzyme activities, and soil C sequestration.

关键词： crop rotation enzyme activity FAME profile fatty acid methyl ester winter wheat

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Exploring the synthesis conditions to control the morphology of gold-iron oxide heterostructures

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Nano Research 2019年第8期12卷 1781-1788页

作者： Pablo Tancredi Luelc Souza da Costa Sebastian calderon Oscar Moscoso-Londono Leandro M. Socolovsky Paulo j. Ferreira Diego Muraca Daniela Zanchet Marcelo Knobel Laboratory of Amorphous Solids INTECINFaculty of EngineeringUniversity of Buenos Aires - CONICETBuenos AiresCP C1063ACVArgentina Department of Inorganic Chemistry Institute of ChemistryUniversity of Campinas (UNICAMP)CP615413083-970CampinasSPBrazil Brazilian Nanotechnology National Laboratory (LNNano) Rua Giuseppe Maximo Scolfaro 10000CampinasSPBrazil International Iberian Nanotechnology Laboratory (INL) Av. Mestre Jose Veiga s/n4715-330 BragaPortugal “Gleb Wataghin” Institute of Physics University of Campinas (UNICAMP)CEP 13083-859CampinasSPBrazil Autonomous University of Manizales Antigua Estacion del FerrocarrilManizalesCP 170001Colombia Facultad Regional Santa Cruz Universidad Tecnoldgica Nacional - CIT Santa Cruz (CONICET)- Av delos Inmigrantes 555Rio GallegosSanta CruzArgentina Materials Science and Engineering Program The University of Texas at AustinAustinTexas 78712USA

Gold-iron oxide nano-heterostructures with a clear and well-defined morphology were prepared via a seed-assisted method. The synthesis process and the events of heterogeneous nucleation during the decomposition of the iron precursor were carefully studied in order to understand the mechanism of the reaction and to tailor the architecture of the fabricated heterostructures. When employing Au seeds of 3 and 5 nm, nanoparticles with a dimer-like morphology were produced due to the occurrence of a single iron oxide nucleation event. Otherwise, multi-nucleation events could be favored by two mechanisms:(i) by the incorporation of a reducing agent and the slowing down of the heating protocol, leading to a core-shell system;(ii) by the increase of the Au seed size to 8 nm, leading to a flower-like system. Further increase of the Au seed size to 12 nm using similar synthesis conditions promotes the homogeneous nucleation and growth of the iron oxide phase, without formation of heterostructures. An in-depth study was performed on the gold-iron oxide heterostructures to confirm the epitaxial growth of the oxide domain over the Au seed and to analyze the elemental distribution of the components within the heterostructures. Finally, it was found that the modification of the plasmonic properties of the Au nanoparticles are strongly influenced by the architecture of the heterostructure, with a more pronounced damping effect for the systems produced after multi-nucleation events.

关键词： nanoparticles gold-iron oxide heterostructures heterogeneous nucleation epitaxial growth HR-microscopy

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A mathematical model of circadian rhythms synchronization using fractional differential equations system of coupled van der Pol oscillators

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International journal of Biomathematics 2018年第1期11卷 313-336页

作者： j. E. Escalante-Martfnez j. F. Gomez-Aguilar C. calderon-Ramon A. Aguilar-Melendez P. Padilla-Longoria Facultad de Ingenieria Mecdnica y Eldctrica Universidad Veracruzana Av. Venustiano Carranza S/N Col. Revolucidn C. P. 93390 Poza Riea Veracruz Mdxico CONACyT-TecnolSgico Nacional de Mexico/CENIDET Interior Internado Palmira S/N Col. Palmira C. P. 62490 Cuernavaca Morelos Mexico Facultad de Ingenier~a Mecdnica y Eldctrica Universidad Veracruzana Av. Venustiano Carranza S/ZN Col. Revolucidn C. P. 93390 Poza Rica Veracruz Mexico Facul$ad de Ingenierd Civil Universidad Veracruzana Av. Venustiano Carranza S/N Col. Revolucion C. P. 93390 Poza Rica Veracruz Mexico Instituto de Investigaciones en Matemdticas Aplicadas ySistemas (IIMAS) UNAM Circuito Escolar Cd. Universitaria Del. Coyoacan Mdxico D. F. C. P. 04510 Mexico

This paper presents an alternative representation of a system of differential equations qualitatively showing the behavior of the biological rhythm of a crayfish during their transition from juvenile to adult stages. The model focuses on the interaction of four cellular oscillators coupled by diffusion of a hormone, a parameter μ is used to simu- late the quality of communication among the oscillators, in biological terms, it mea- sures developmental maturity of the crayfish. Since some quorum-sensing mechanism is assumed to be responsible for the synchronization of the biological oscillators, it is nat- ural to investigate the possibility that the underlying diffusion process is not standard, i.e. it may be a so-called anomalous diffusion. In this case, it is well understood that diffusion equations with fractional derivatives describe these processes in a more realis- tic way. The alternative formulation of these equations contains fractional operators of Liouville-Caputo and Caputo-Fabrizio type. The numerical simulations of the equations reflect synchronization of ultradian rhythms leading to a circadian rhythm. The classical behavior is recovered when the order of the fractional derivative is V = 1. We discuss possible biological implications.

关键词： Circadian rhythm van der Pol oscillators Liouville-Caputo fractional oper-ator Caput^Fabrizio fractional operator Adams Bashforth Moulton method syn-chronicity.

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Hair follicles as a target structure for nanoparticles

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journal of Innovative Optical Health Sciences 2015年第4期8卷 2-9页

作者： j.Lademann F.Knorr H.Richter S.jung M.C.Meinke E.Rühl U.Alexiev M.calderon A.Patzelt Center of Experimental and Applied Cutaneous Physiology Department of Dermatology Venereology and Allergology Charite-Universitatsmedizin Berlin Chariteplatz 1Berlin 10117Germany Physical Chemistry Institute of Chemistry and Biochemistry Freie Universitat Berlin Takustr.3Berlin 14195Germany Department of Physics Freie Universitat Berlin Arnimallee 14Berlin 14195Germany

For at least two decades,nanoparticles have been investigated for their capability to deliver topically applied substances through the skin *** on findings that nanoparticles are highly suitable for penetrating the blood--brain barrier,their use for drug delivery through the skin has become a topic of intense *** spite of the research efforts by academia and industry,a commercial product permitting the nanoparticle-assisted delivery of topically applied drugs has not yet been ***,nanoparticles of approximately 600 nm in diameter have been shown to penetrate fficiently into the hair fllieles where they can be stored for several *** successful loading of nanoparticles with drugs and their triggered release inside the hair fllile may present an ideal method for localized drug *** on the particle size,such a method would permit targeting specific structures in the hair fllicles such a stem ells or immune cells or blood vessels found in the vicinity of the hair follicles.

关键词： Skin barrier penetration stratum corrneum hair fllicles triggered release

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Illusion and Imagination in Cinema According to Bazin

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journalism and Mass Communication 2013年第8期3卷 541-547页

作者： Alberto j. L. Carrillo Luis R. Vera Marco A. calderon Freie Universitat Benemerita Universidad Autonoma de Puebla University of New Mexico

Bazin favored every means to increase the ＂reality coefficient＂ in cinema. He specially prized cinema showing events integrally, what means, on the one hand, to show simultaneously and fully all the characters and all the objects pertaining to an event, and on the other to show the event integrally as it develops in time. Additionally Bazin showed that such a procedure reduces the purely literary component in cinema, and, correspondingly, increases its illusory force--as to the fictional reality presented. Yet, Bazin＇s work is not systematic, giving us brilliant insights scattered through many essays. Following Bazin＇s main idea, this presentation attempts to systematically discuss the illusory potential of the shot presenting an event integrally as compared with the imaginary, that is, literary character introduced in cinema by suggesting an event by means of montage and fragmentary shots. We proceed by means of a detailed consideration of the belief-structure of the aesthetic experience corresponding to the single shot integrally showing an event and to montage suggesting an event by means of fragmentary shots. The core of the presentation lies in defining the concept of aesthetic belief as the propositional attitude having the structure accepting that P without believing that P is the case. We will carefully distinguish that structure in the case of illusion from the case of imagination as well as from illusion as sensory-based deception.

关键词： cinema literature illusion imagination belief

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Hopf Bifurcation Control in a Lorenz Type System

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journal of Applied Mathematics and Physics 2018年第8期6卷 1704-1719页

作者： P. E. calderon-Saavedra E. Munoz-Aguirre j. Alvarez-Mena S. Gomez-Perez Universidad del Tolima Ibagué Colombia Universidad Veracruzana Veracruz Mexico

In this paper Hopf bifurcation control is implemented in order to change the bifurcation from supercritical to subcritical in a differential equations system of Lorenz type. To achieve this purpose: first, a region of parameters is identified where the system has a supercritical Hopf bifurcation;second, a class of non-linear feedback control laws is proposed;finally, it is shown that there are control laws which the disturbed system undergoes subcritical Hopf bifurcation.

关键词： Lorenz Type Systems Bifurcation Control Hopf Bifurcation Control Subcritical and Supercritical Hopf Bifurcation

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光电传感器跟踪瞬态过程

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电子技术应用 1996年第6期22卷 56-58页

作者： R.Ceres j.M.Martin L.calderon M.Armada j.L.Pons 王守杰

工业机器人,由于需要具有快速与低能耗特性,要求其机构轻.尤其是安装在卫星上的机器人更要求其轻便.当轻型机器人带有一重的末端执行器时,机械臂不再是刚性的,由于它们的柔性,可能发生所不希望频率下的振动.因此,为了控制机器人臂的运... 详细信息

工业机器人,由于需要具有快速与低能耗特性,要求其机构轻.尤其是安装在卫星上的机器人更要求其轻便.当轻型机器人带有一重的末端执行器时,机械臂不再是刚性的,由于它们的柔性,可能发生所不希望频率下的振动.因此,为了控制机器人臂的运动及抑制或减小振动幅度,需要复杂的位置控制.

关键词：工业机器人光电传感器跟踪瞬态过程

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