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Aquaculture and Fisheries 2021年第1期6卷 69-74页

作者： Mario Nieves-Soto Ricardo lozano-Huerta diana j.lòpez-peraza María A.Medina-jasso Miguel AHurtado-Oliva joséF.Bermudes-lizárraga Facultad de Ciencias del Mar Universidad Autónoma de SinaloaPaseo Claussen s/n.Los PinosMazatlánC.P.8200Mexico

Artemia is deficient in polyunsaturated fatty acids(PUFAs),particularly in arachidonic(ARA,20:4n-6),eicosapentaenoic(EPA,20:5n-3),and docosahexaenoic acid(DHA,22:6n-3).The aim of this study was to determine the optimal time in which the higher contents of PUFAs in juveniles of Artemia franciscana were obtained by the effect of enrichment with the tuna orbital oil *** enrichment periods were evaluated:3,6,9,12,15 and 18 h,in addition to a control treatment(0 h).The most abundant fatty acids in *** were monounsaturated(43.10%±4.35–52.92%±5.82%),followed by saturated(33.83%±1.71–42.33%±2.31%)and PUFAs(8.86%±2.83%–21.32%±2.38%).ARA decreased over the enrichment time;the maximum content was 5.74±0.37%at 3 h,which was not statistically different with respect to the content recorded at 0 *** highest content of EPA was at 3 h(6.47%±1.44%),without significant differences with the content registered at 0 h,while that from 6 h and until 15 h tended to decrease *** 6 h,the content of DHA(8.84%±2.72%)was significantly higher compared to the rest of the treatments,which did not differ among themselves,or with the *** to the 6 h and until 15 h,the content of PUFAs tended to decrease,which could indicate the metabolization of them by ***,coupled with the possible oxidation of these fatty acids in the enrichment solution.

关键词： Artemia franciscana juveniles Bioencapsulation Essential fatty acids Tuna orbital oil emulsion

Modelling sulphate-enhanced cadmium uptake by Zea mays from nutrient solution under conditions of constant free Cd^(2+) ion activity

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journal of Environmental Sciences 2010年第7期22卷 1080-1085页

作者： Ulrico j.lópez-Chuken Scott D.Young Division of Environmental Sciences School of ChemistryUniversidad Autónoma de Nuevo León Division of Agricultural & Environmental Sciences School of Biosciencesthe University of Nottingham

A controlled hydroponic experiment was undertaken to investigate Cd uptake in relation to the activity of Cd species in solution other than the free ion （Cd^2＋） by maintaining a constant Cd^2＋ activity under variable SO4^2- and Cl^- concentrations exposed to maize （Zea mays vat. Cameron） plants. The objectives of these experiments were：（1） to distinguish and quantify the different uptake rates of free and inorganic-complexed Cd from nutrient solution, and （2） to model the uptake of Cd by maize with a Biotic ligand Model （BlM） in a system which facilitates the close examination of root characteristics. Results of the current experiments suggest that, in addition to the free ion, CdSO4^0 complexes are important factors in determining Cd uptake in nutrient solution by maize plants. Higher nominal SO4^2- concentrations in solution generally resulted in a greater Cd accumulation by maize plants than predicted by the Cd^2＋ activity. A better integration of the complete dataset for the 3 harvest times （6, 9 and 11 days after treatment） was achieved by including consideration of both the duration of Cd exposure and especially the root surface area to express Cd uptake. Similarly, the fit of the BlM was also improved when taking into account exposure time and expressing uptake in terms of root morphological parameters.

关键词： free ion activity model biotic ligand model root surface area Cd complexation metal exposure time hydroponics plant uptake

Assessing the estrogenic potency in a Portuguese wastewater treatment plant using an integrated approach

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journal of Environmental Sciences 2010年第10期22卷 1613-1622页

作者： Mário S.Diniz Rita Maurício Mira Petrovic Maria j.lópez De Alda leonor Amaral Isabel Peres Damiá Barceló Fernando Santana Universidade Nova de lisboa Faculdade de Ciencias e TecnologiaREQUIMTEDep.de Quimica Universidade Nova de lisboa Faculdade de Ciencias e TecnologiaDep.de Ciencias e Engenharia do Ambiente Department of Environmental Chemistry-IIQAB-CSIC c/jordi Girona

The estrogenic potency of a wastewater treatment plant （WWTP） was evaluated using chemical and biological analyses, which showed that after the station treatment processes some of the selected endocrine disruptor compounds （EDCs） were still present in the treated effluent （e.g., bisphenol A, alkylphenols, estrone）. Thus, the most common endocrine EDCs were identified and quantified and the overall estrogenicity of the treated effluent assessed by integrating the results. Male goldfish （Carassius auratus） were used as biological indicators in a 28-day experiment. Vitellogenin （Vtg）, gonadosomatic and hepatosomatic indices, steroids （17β-estradiol and 11-ketotestosterone） and histopathology were biomarkers used in fish to evaluate WWTP treated effluent estrogenicity, in combination with instrumental analyses. The results showed a significant increase （P 〈 0.01） in plasma and liver Vtg, which were significantly correlated （r = 0.66; P 〈 0.01）. The gonadosmatic index was significantly （P 〈 0.01） reduced in exposed fish. The steroid analyses revealed significant elevations in 17β-estradiol and depressed 11-ketotestosterone concentrations. The histological examinations show changes in exposed fish gonads, such as regressed testes and in some cases （43% to 75%） the development of ovo-testis in fish exposed to 50% and 100% treated effluent.

关键词： Carassius auratus endocrine disruptors vitellogenin steroids intersex

A new device for deep cervical artificial insemination in gilts reduces the number of sperm per dose without impairing final reproductive performance

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journal of Animal Science and Biotechnology 2019年第2期10卷 402-409页

作者： Pedro j.llamas-lópez Rebeca lópez-úbeda Gustavo lópez Emily Antinoja Francisco A.García-Vázquez Department of Physiology Faculty of VeterinaryCampus Mare NostrumUniversity of Murcia30100 MurciaSpain Department of Cell Biology and Histology Faculty of MedicineCampus Mare NostrumUniversity of Murcia30100 MurciaSpain Institute for Biomedical Research of Murcia(IMIB-Arrixaca) MurciaSpain Cherkizovo Group LipetskRussia.

Background: The aim of this study was to evaluate the reproductive performance of a new artificial insemination(AI) device specifically designed for gilts(Deep cervical AI, Dp-CAI) by means of which the sperm is deposited deeply in the cervix(8 cm more cranial than in traditional cervical insemination-CAI). New AI techniques have arisen in recent decades in the porcine industry, such as post-cervical artificial insemination(PCAI), which involves depositing the sperm in the body of the uterus [through a catheter(outer tube)-cannula(inner tube)] rather than by CAI. Although the PCAI method has been successfully applied in farm conditions to reduce sperm doses without impairing the reproductive performance, this technique has limitations in gilts mainly because of the difficulty involved in introducing the inner cannula through the cranial part of the cervix. For this reason, the Dp-CAI method described herein may be considered as an alternative to CAI and PCAI methods in ***: Gilts were divided in two experimental groups: 1) Dp-CAI: gilts(n = 1166) inseminated using 1.5 × 109 sperm/45 m l;2) CAI(as a control group): gilts(n = 130) inseminated using 2.5 × 10~9 sperm/85 ml. The Dp-CAI method was successfully applied in 88.90% of the gilts, with no differences detected between gilts with 1 or 2 previous oestrus cycles, although the catheter could be introduced more deeply in 2 oestrus gilts(P length of the insemination device that could not be introduced increased(at the moment of insemination), so the success rate of the Dp-CAI device fell, as did the total number of piglets born. When the reproductive output in CAI and Dp-CAI was compared, none of the parameters analysed [pregnancy and farrowing rates(%), and number of piglets born(total and live)] showed significant ***: The use of the Dp-CAI technique provides a new AI method as an alternative to CAI and PCAI for pigs. The device, especially designed for gilts, was used w

关键词： Cervix Intrauterine Nulliparous Porcine Post-cervical insemination

Existence and Uniqueness of Fixed Point in Partially Ordered Sets and Applications to Ordinary Differential Equations

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Acta Mathematica Sinica,English Series 2007年第12期23卷 2205-2212页

作者： juan j.NIETO RosanaRODRGUEZ-lpez Departamento de Análisis Matemático Facultad de MatemáticasUniversidad de Santiago de Compostela

We prove some fixed point theorems in partially ordered sets, providing an extension of the Banach contractive mapping theorem. Having studied previously the nondecreasing case, we consider in this paper nonincreasing mappings as well as non monotone mappings. We also present some applications to first-order ordinary differential equations with periodic boundary conditions, proving the existence of a unique solution admitting the existence of a lower solution.

关键词： fixed point partially ordered set first-order differential equation lower and upper solutions

Conservation laws for energy and momentum in curved spaces

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 665-668页

作者： lópez-BONIllA j. MORAlES j. OVANDO G. Section of Postgraduate Studies and Research Superior School of Mechanical and Electrical EngineeringNational Polytechnic InstituteCP 07738Mexico Division of Basic Sciences and Engineering Autonomous Metropolitan UniversityCP 02200Mexico

In arbitrary Riemannian 4-spaces, continuity equations are constructed which could be interpreted as conservation laws for the energy and momentum of the gravitational field. Special attention is given to general relativity to obtain, of natural manner, the pseudotensors of Einstein, landau-lifshitz, Moeller, Goldberg and Stachel, and also the conservation equations of Komar, Trautman, DuPlessis and Moss.

关键词： Noether theorem lagrangians in curved spaces Energy and momentum in Riemannian spaces Rund-lovelock identities

In-vitro assessment for the control of Fusarium species using a lactic acid bacterium isolated from yellow pitahaya(Selenicereus megalanthus(K. Schum. Ex Vaupel Moran))

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journal of Integrative Agriculture 2021年第1期20卷 159-167页

作者： leidy j.VAlENCIA-HERNANDEZ Karina lÓOpez-lÓpez Eyder D.GÓMEZ-lÓpez liliana SERNACOCK Cristobal N.AGUIlAR Universidad Nacional de Colombia Palmira CampusValle 763533Colombia Food Research Department School of ChemistryAutonomous University of CoahuilaSaltillo CampusCoahuila 25280Mexico

The fungistatic activity of a lactic acid bacterium, which had been isolated from yellow pitahaya cultures, against fungi associated with basal rot(Fusarium oxysporum and Fusarium fujikuroi) was measured in the present study. Its activity was assessed in three fractions: fermented(S1), metabolic products(S2), and biomass(S3), using two fermentation substrates: Man Rogosa Sharpe agar(MRS) and potato dextrose agar(PDA). The bacterium was molecularly identified as lactobacillus plantarum. S3 reduced F. fujikuroi growth by 100% over 48 h of fermentation, which occurred during the stationary phase of bacterial growth. The three fractions' fungistatic activity against F. fujikuroi depended on the substrate employed. The fermentation kinetic parameters for l. plantarum indicated that its specific growth rate was 0.46 h^–1, with 93.63% substrate consumption, 0.045 kg kg^–1 cell yield, and 0.54 kg kg^–1 product yield. The kinetic parameters calculated will allow for bacteria production scaling. These in-vitro trials reveal l. plantarum's possible application as a biocontrol agent for diseases associated with Fusarium. However, further ex-vivo and in-vivo researches are required to demonstrate its behavior in crops.

关键词： lactic acid bacteria Fusarium fungistatic activity biomass yellow pitahaya

Patterns of trends in niveograph characteristics across the western United States from snow telemetry data

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Frontiers of Earth Science 2020年第2期14卷 315-325页

作者： S.R.FASSNACHT j.I.lÓpez-MORENO ESS-Watershed Science Colorado State UniversityFort CollinsCO 80523-1472USA Cooperative Institute for Research in the Atmosphere Colorado State UniversityFort CollinsCO 80523-1375USA Natural Resources Ecology laboratory Colorado State UniversityFort CollinsCO 80523-1499USA Instituto Pirenaico de Ecología CSICCampus de Aula Dei 50080Spain

The snowpack is changing across the globe,as the climate warms and *** used daily snow water equivalent(SWE)niveograph(time series of SWE)data from 458 snow telemetry(SNOTEl)stations for the period 1982 through *** indices based on amount,timing,time length,and rates were used to describe the annual temporal evolution in SWE accumulation and *** trends in these annual indices were computed over the time period for each station using the Theil-Sen *** trends were then clustered into four groups to determine the spatial pattern of SWE *** and precipitation data were extracted from the PRISM data set,due to the shorter time period of temperature measurement at the SNOTEl *** show that SNOTEl stations can be clustered in four clusters according to the observed trends in snow *** 1 stations are mostly located in the Eastern-and South-eastern most parts of the study area and they exhibit a generalized decrease in the indices related with peak SWE and snow *** stations recorded a negative trend in precipitation and an increase in *** 4 that is mostly restricted to the North and North-west of the study area shows an almost opposite pattern to cluster 1,due to months with positive trends and a more moderate increase of *** grouped in clusters 2 and 3 appear mixed with clusters 1 and 4,in general they show very little trends in the snow indices.

关键词： snow water equivalent cluster analysis SNOTEl

Simulation factors of steel continuous casting

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International journal of Minerals,Metallurgy and Materials 2010年第3期17卷 267-275页

作者： A.Ramírez-lópez R.Aguilar-lópez A.Kunold-Bello j.González-Trejo M.Palomar-Pardavé Department of Materiales Metropolitan Autonomous University Institute Polytechnic National Institute Technologic Autonomous of Mexico

The factors involved in simulating the continuous casting process of steel and the effects of the factors on the thermal behavior were investigated. The numerical methods and the influence of some assumptions were also analyzed, such as nodes used to discretize the steel in array size and computing time to obtain good approaches. The results show that some of these factors are related with the design of the continuous casting plant （CCP）, such as geometrical configuration, and the operating conditions, such as water flow rate, heat removal coefficient in the mold, casting times, and casting speed in the strand, which affect the heat removal conditions over the temperature and solidification profiles.

关键词： continuous casting thermal behavior numerical method computer simulation

Existence of Nondecreasing and Continuous Solutions of an Integral Equation with linear Modification of the Argument

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Acta Mathematica Sinica,English Series 2007年第9期23卷 1719-1728页

作者： j.CABAllERO B.lópez K.SADARANGANI Departamento de Matemáticas Universidad de Las Palmas de Gran CanariaCampus de Tafira Baja35017 Las Palmas de Gran CanariaSpain

We use a technique associated with measures of noncompactness to prove the existence of nondecreasing solutions to an integral equation with linear modification of the argument in the space C[0, 1]. In the last thirty years there has been a great deal of work in the field of differential equations with a modified argument. A special class is represented by the differential equation with affine modification of the argument which can be delay differential equations or differential equations with linear modifications of the argument. In this case we study the following integral equation x（t） = a（t）＋（Tx）（t） ∫0^σ（t） u（t, s, x（s）, x（λs））ds 0 〈 λ 〈 1 which can be considered in connection with the following Cauchy problem x＇（t） = u（t, s, x（t）, x（λt））, t ∈ [0, 1], 0 〈 λ 〈 1 x（0） = u0.

关键词： measure of noncompactness fixed point theorem nondecreasing solutions