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Sample Size Dependence of Second Magnetizaion Peak in Type-ⅡSuperconductors

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Tsinghua Science and Technology 2003年第3期8卷 370-378页

作者： J.H.S.torres Y.Kopelevich Institute de fisica"Gleb Wataghin" Universitade Estadual de CampinasUnicamp 13083-970CampinasSao PauloBrasilInstitute de fisica"Gleb Wataghin"Universitade Estadual de CampinasUnicamp 13083-970CampinasSao PauloBrasil

We show that the second magnetization peak(SMP),i.e.,an increase in the magnetization hysteresis loop width in type-11 superconductors,vanishes for samples smaller than a critical size,We argue that the SMP is not related to the critical current enhancement but can be well explainde within a frameword of the thermomagenetic flux-jump in stability theory,where flux jumps reduce the absolute irreversible magnetization relative to the isothermal critical state value at low enough magnetic *** recovering of the isothermal critical sate with increasing field leads to the *** low-field SMP takes place in both *** and high**** *** results show that the rsstoration of the isothermal critical state is rsponsible for the SMP occurrence in both cases.

关键词： Superconductor flux pinning and creep peekeffect phase transityons

relationship between PON-1 enzymatic activity and risk factors for pesticide poisoning in farmers from the Cienega,Jalisco,Mexico

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BIOCELL 2021年第5期45卷 1241-1250页

作者： HAZAEL rAMIrO CEJA-GALVEZ ErANDIS DHENI torres-SÁNCHEZ JUAN HErIBErTO torres-JASSO EMMANUEL rEYESUrIBE JOEL SALAZAr-FLOrES Department of Medical and Life Sciences University Center of La CienegaUniversity of Guadalajara(CUCI-UdeG)OcotlánCP 47810Mexico Department of Biological Sciences University Center of the CoastUniversity of Guadalajara(CUCosta-UdeG)Puerto VallartaCP 48280Mexico

Paraoxonase-1(PON-1)is an enzyme that hydrolyzes organophosphate *** presence of polymorphisms in PON-1(L55M and Q192r)decreases its enzyme activity and increases the risk of central nervous system(CNS)toxicity in occupationally exposed farmers,leading to chronic degenerative diseases and *** studied 103 farmers in the region of Cienega Jalisco,Mexico,which were exposed mainly to organophosphate *** used serum and plasma samples to assay PON-1 activity and perform polymorphism analysis(L55M and Q192r)using qPCr and TaqMan probes,*** both polymorphisms,there was high percentage of heterozygosity(55 LL=0.19,LM=0.75,MM=0.06;192 QQ=0.12,Qr=0.72,rr=0.16),while the allelic frequencies were more balanced(L=0.56,M=0.44;Q=0.48,r=0.52).There were no significant differences in enzyme activity of L55M polymorphism genotypes(LL=179.27;LM=192.11;MM=122.11;QQ=135.74;Qr=187.90;rr=209;p>0.05).But there was a slight decrease in enzyme activity for the Q192r polymorphism *** genotype and alcohol consumption associated with slight increases in enzyme ***,genotype and tobacco consumption did not have a significant effect on PON-1 activity(μU/mL)(p>0.05).Overall,alcohol and tobacco consumption affected PON-1 enzyme activity(μU/mL)up to 21.1%.The data obtained in this study reveal that PON-1 activity is affected by genetic variants such as Q192r and alcohol *** may influence the susceptibility of populations to organophosphate poisoning.

关键词： Paraoxonase-1 Pesticides Organophosphates Polymorphisms

Distribution of Malpighia mexicana in Mexico and its implications for Barranca del río Santiago

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Journal of Forestry research 2021年第3期32卷 1095-1103页

作者： Martín Tena Meza rafael MaNavarro-Cerrillo Diego Brizuela torres Instituto de Botánica Centro Universitario de Ciencias Biológicas y AgropecuariasUniversidad de GuadalajaraMéxicoCamino Ramón Padilla Sánchez No.2100.Nextipac45200 ZapopanJaliscoMexico Depto.Ingeniería Forestal Laboratorio de SelviculturaDendrocronología y Cambio ClimáticoDendrodatLab-ERSAFUniversidad de CórdobaCampus de RabanalesCtra.N-IVkm.39614071 CórdobaSpain Departamento de Producción Forestal Centro Universitario de CienciasBiológicas y AgropecuariasUniversidad de GuadalajaraMéxicoCamino Ramón Padilla Sánchez No.2100 Nextipac45200 ZapopanJaliscoMexico

Wild plants represent relatively unexplored resource of high economic potential,especially as an alternative to developing new crops and,even more relevant,for improving existing crops and contributing to nutrition and *** wild species M alpighia mexicana(manzanita)has a wide tradition of food,medicinal and ornamental use in *** is part of the American-origin group of tropical shrubs that produce edible red fruits,such as A cerola,which is considered the most important natural source of vitamin C in the *** the role played by *** in Mexico,and particularly in Barranca del río Santiago(Santiago river Canyon),we modelled its potential distribution in both geographical *** used species'records from databases,local herbaria and records collected by the authors as well as climatic variables representing long term average,variability and extreme conditions of temperature and *** fit the models we used the modelling algorithm Maxent and selected an adequate configuration by testing a range of model complexity *** results indicate a clear species preference for warm-dry tropical forest,most extensively in the Balsas river depression and the central valleys of *** probability of the species presence in the western region was also high,although the probability was also high for smaller surface areas,such as the region of Santiago river canyons,which are covered by warm-dry tropical forests.

关键词： Malpighia mexicana Maxent Warmdry tropical forest río Santiago Genetic resources Ecological niche model Manzanita

Constant-gain nonlinear adaptive observers revisited: an application to chemostat systems

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Frontiers of Information Technology & Electronic Engineering 2021年第1期22卷 68-78页

作者： Jorge A.torres Arno SONCK Sergej CELIKOVSKY Alma r.DOMINGUEZ Automatic Control Department CINVESTAVMexico City 07360Mexico The Czech Academy of Sciences Institute of Information Theory and AutomationPrague 18200Czech Republic Biotechnology and Bioengineering Department CINVESTAVMexico City 07360Mexico

This study deals with constant-gain adaptive observers for nonlinear systems,for which relatively few solutions are available for some particular *** introduce an asymptotic observer of constant gain for nonlinear systems that have linear *** allows the observer design to be formulated within the linear matrix inequality paradigm provided that a strictly positive real condition bet ween the inpu t disturbance and the output is *** proposed observer is t hen applied to a large class of nonlinear chemos tat dynamical systems that are widely used in the fermentation process,cell cultures,medicine,*** fact,under standard practical assumptions,the necessary change of the chemos tat state coordinates exis ts,allowing use of the const ant-gain ***,the developed theory is illustrated by estimating pollutant concentration in a Spirulina maxima wastewater treatment facility.

关键词： Nonlinear observers Adaptive observers Coordinate change Chemos tat Pollu taut observation

The number of alignments between two DNA sequences

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International Journal of Biomathematics 2016年第4期9卷 75-80页

作者： Helena Andrade Juan J. Nieto Angela torres Departamento de Andlisis Matemdtico Facultad de Matemdticas Universidad de Santiago de Compostela Spain Department of Mathematics Faculty of ScienceKing Abdulaziz University Jeddah 21589 Saudi Arabia Departamento de Psiquiatrla Radiologla y Salud Publica Facultad de Medicina Universidad de Santiago de Compostela Spain

We consider two DNA sequences and compare both sequences. One of the crucial issues in bioinformatics is to measure the similarity of two DNA sequences. To this purpose one has to consider different alignments between both sequences. The number of alignments grows very rapidly with the length of the sequences. In this paper we give exact, explicit and computable formulas for the number of different possible alignments and for some classes of reduced alignments. We provide a new insight into the theory of DNA sequence alignment.

关键词： DNA sequence alignment difference equation.

Variable retention harvesting: conceptual analysis according to different environmental ethics and forest valuation

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Ecological Processes 2019年第1期8卷 485-491页

作者： Leonardo Galetto Carolina torres Guillermo J.Martínez Pastur Departamento de Diversidad Biológica y Ecología FCEFyNUniversidad Nacional de Córdoba(UNC)Vélez Sarsfield 16115000 CórdobaArgentina Instituto Multidisciplinario de Biología Vegetal(IMBIV) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Vélez Sarsfield 16115000 CórdobaArgentina Centro Austral de Investigaciones Científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 2009410 UshuaiaTierra del FuegoArgentina.

Background:Conceptual clarity is important to attain precise communication of scientific knowledge and to implement appropriate technological and policy *** concepts referring to forest management are widely used by decision-makers,regardless of their *** the scientific and methodological issues of forestry practices are frequently discussed in the literature,their normative dimensions are rarely ***,linguistic uncertainty increases when different environmentally ethical perspectives and ways of valuing forests are *** objective was to compare different conceptualizations on the silvicultural systems suggested for forest management and the implications they have for *** have conceptually contrasted highintensity forestry practices with variable retention harvesting,considering different environmentally ethical perspectives and forest valuation ***:Clear boundaries between clear-cutting,selective logging,and variable retention harvesting can be evidenced when different ethical points of view and alternatives in the human-nature relationships are *** have found a variety of definitions of variable retention harvesting that can be analyzed under different ethical *** contrasting views on variable retention harvesting can be evidenced if nature is considered to be purely at human’s service or if it is conceptualized as humans co-inhabiting with *** latter position implies that the maintenance of ecological,evolutionary,and historical processes supported by unmanaged forest stands is a crucial step for forest management proposals based on variable retention ***:Forestry practices that are focused on forest yields and that misinterpret functional uncertainty of forest functioning would be ***,forestry with variable retention harvesting could imply good yields with reasonable conservation management in some contexts,while it could be unacce

关键词： Environmental ethical perspectives Consequentialism Deontological ethics Virtue ethics Policy options for forest and biocultural conservation

Composition and Physico-Chemical Properties of Meat from Capons Fed Cereals

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Journal of Integrative Agriculture 2013年第11期12卷 1953-1960页

作者： Olga Díaz Luisana rodríguez Alexandr.torres ngel Cobos Food Technology Division Department of Analytical ChemistryNutrition and Food ScienceFaculty of SciencesUniversity of Santiago de Compostela

Chemical composition, physico-chemical properties and fatty acid composition of breast and drumstick meat from capons （castrated male cockerels） fed cereals were studied. Three groups of capons were reared. One group was fed ad libitum the same commercial diet until the 4th mon of life. The last month of its life, the capons of this group were fed corn. The second and third group of capons were fed the same diet from caponization. The second group was fed mixture of corn （50%） and wheat （50%）. The third group of capons was fed 2/3 corn and 1/3 mixture of corn （50%） and barley （50%）. Capons were reared under free-range conditions and slaughtered at 150 d of age. Caponization was performed at 48 d. No signiifcant effects of feeding in chemical composition, pH, water holding capacity, drip and cooking losses and texture of the meat were observed. The meat of the third group （capons fed 83%corn） was more yellow and showed higher content of C18：2 than that of the other capons.

关键词： castrated male cockerel feeding meat quality fatty acids

Tribological performance of iron- and nickel-base self-lubricating claddings containing metal sulfides at high temperature

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Friction 2022年第12期10卷 2069-2085页

作者： Hector.torres Tugce CAYKArA Jens HArDELL Janne NUrMINEN Braham PrAKASH Manel rODrIGUEZ rIPOLL AC2T research GmbH Viktor-Kaplan-Straße 2/CWiener Neustadt 2700Austria Department of Applied Physics and Mechanical Engineering LuleåUniversity of TechnologyLuleå97187Sweden Castolin Eutectic GmbH Gutenbergstraße 10Kriftel 65830Germany Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

Iron-based coatings with the incorporation of solid lubricants have been prepared by means of laser cladding,in an effort to control friction and decrease tool wear at high temperatures during metal forming *** choice of a Fe-based powder has been considered advantageous,as it can lead to decreased costs compared to nickel-based claddings previously studied by the authors,in addition to having a lower environmental *** particular,the incorporation of transition metal dichalcogenides such as MoS_(2) as precursors leads to the encapsulation of silver in Fe-based self-lubricating claddings,resulting in a uniform distribution of the soft metal across the thickness of the *** tribological evaluation of the claddings at high temperatures shows that the addition of lubricious compounds leads to lower friction at room temperature and significantly decreased wear up to 600℃ compared to the unmodified iron-based reference alloy,although higher than similar self-lubricating Ni-based *** order to cast light into these observed differences,the corresponding microstructures,phase composition,and self-lubricating mechanisms have been studied and compared for Fe-and Ni-based claddings having both of them the addition of silver and MoS_(2).The results suggest a key role of the formation of protective tribolayers on the counter body during high temperature sliding *** simulation of the phase evolution during solidification reveals that the formation of different chromium-and nickel-based metal sulfides in Fe-and Ni-claddings during laser cladding by the decomposition of MoS_(2) plays a key role in determining their tribological behaviour at high temperatures.

关键词： high temperature laser cladding self-lubrication metal forming chromium sulphide MoS_(2)

Effect of structure and function of paraoxonase-1(PON-1)on organophosphate pesticides metabolism

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BIOCELL 2020年第3期44卷 363-370页

作者： HAZAEL rAMIrO CEJA-GÁLVEZ ErANDIS DHENI torres-SÁNCHEZ JUAN HErIBErTO torres-JASSO ArTUrO VILLALOBOS OrNELAS JOEL SALAZAr-FLOrES Department of Medical and Life Sciences University Center of La CiénegaUniversity of Guadalajara(CUCI-UdeG)OcotlánCP 47810Mexico Department of Biological Sciences University Center of the CoastUniversity of Guadalajara(CUCosta-UdeG)Puerto VallartaCP 48280Mexico

Paraoxonase-1(PON1)is an important enzyme in various pathologies such as pesticide poisoning,diabetes,atherosclerosis,neuronal disorders,and cancer,due to its multifunctional activity since it acts on different ***,one of its main functions is the hydrolysis of organophosphate(OP)compounds from pesticides that cause fatal poisoning at the level of the central nervous system(CNS).The objective of this review was to investigate whether the structure,genetics,and function of PON1 affect the metabolism of organophosphate pesticides or other *** was selected from articles in the database PubMed–NCBI(https://***/pubmed/)with a publication date between 2011 and *** enzymatic activity of PON1 can be modified depending on its chemical structure since there are different genetic polymorphisms that change PONI morphologies or the levels of expression in the *** leads to differences in susceptibilities to organophosphate pesticide *** results of this review reveal that phenotypic variants of PON1 have differences in affinities for OP substrates.

关键词： PON1 Pesticides Organophosphorus toxicity