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Methionine sources and genotype affect embryonic intestinal development,antioxidants,tight junctions,and growth-related gene expression in chickens

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Animal Nutrition 2024年第1期16卷 218-230页

作者： james K.Lugata Sawadi F.Ndunguru Gebrehaweria K.reda Xénia E.Ozsváth Eszter Angyal Levente Czeglédi Gabriella Gulyás renáta Knop jános Oláh Zoltán Mészár rita Varga Brigitta Csernus Csaba Szabó Department of Animal Nutrition and Physiology Faculty of Agriculture and Food Sciences and Environmental ManagementUniversity of DebrecenDebrecenHungary Department of Animal Husbandry Faculty of Agriculture and Food Sciences and Environmental ManagementUniversity of DebrecenDebrecenHungary Faculty of Agriculture and Food Sciences and Environmental Management Doctoral School of Animal ScienceUniversity of DebrecenDebrecenHungary Institutes for Agricultural research and Educational Farm University of DebrecenDebrecenHungary Department of Anatomy Histology and EmbryologyFaculty of MedicineUniversity of DebrecenDebrecenHungary Department of Evolutionary Zoology and Human Biology Faculty of Science and TechnologyUniversity of DebrecenDebrecenHungary

Methionine(Met)is an essential and first limiting amino acid in the poultry diet that plays a significant role in chicken embryonic development and *** present study examined the effect of in ovo injection of DL-Met and L-Met sources and genotypes on chicken embryonic-intestinal development and *** eggs of the two genotypes,TETrA-SL layer hybrid(TSL)—commercial layer hybrid and Hungarian Partridge colored hen breed(HPC)—a native genotype,were randomly distributed into four treatments for each *** treatment groups include the following:1)control non-injected eggs(NoIn);2)saline-injected(SaIn);3)DL-Met injected(DLM);and 4)L-Met injected(LM).The in ovo injection was carried out on 17.5 d of embryonic development;after hatching,eight chicks per group were sacrificed,and the jejunum was extracted for *** results showed that both DLM and LM groups had enhanced intestinal development as evidenced by increased villus width,villus height,and villus area(Pred to the *** DLM group had significantly reduced crypt depth,glutathione(GSH)content,glutathione S-transferase 3 alpha(GST3),occludin(OCLN)gene expression and increased villus height to crypt depth ratio in the TSL genotype than the LM group(Prexpressed insulin-like growth factor 1(IGF1)gene,tricellulin(MD2),occludin(OCLN),superoxide dismutase 1(SOD1),and GST3 genes than the TSL genotype(Pjection of Met enhanced intestinal development,and function,with genotypes responding differently under normal *** also influenced the expression of intestinal antioxidants,tight junction,and growth-related genes.

关键词： DL-Methionine L-Methionine In ovo injection Intestinal development Poultry

Optimization Model for School Transportation Based on Supply-Demand Analyses

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journal of Software Engineering and Applications 2019年第6期12卷 215-225页

作者： jairo Ortega jános Tóth juan Palaguachi Imad Sabbani Department of Transport Technology and Economics Budapest University of Technology and Economics Budapest Hungary Department of Transportation Escuela Superior Politécnica of Chimborazo Riobamba Ecuador Department of Sciences and Techniques University of Hassan II and Franche-Comté University Besan&#231 on France

This paper presents a new conception model of school transportation supply-demand ratio (STSDr) in order to define the number of school buses needed in a limited area and to describe the conditions of school transport system. For this purpose, a mathematical equation was elaborated to simulate the real system based on the school transport conditions and on the estimated results of STSDr from 15 zones of Cuenca city in Ecuador. The data used in our model was collected from several diverse sources (i.e. administrative data and survey data). The estimated results have shown that our equation has described efficiently the school transport system by reaching an accuracy of 96%. Therefore, our model is suitable for statistical estimation given adequate data and will be useful in school transport planning policy. Given that, it is a support model for making decisions which seek efficiency in supply and demand balance.

关键词： School Transport Model Optimization Supply-Demand Travel to School

褪黑素合成酶基因转化烟草及转化植株抗氧化系统变化

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生物工程学报 2009年第7期25卷 1014-1021页

作者：王英娟贾敬芬步怀宇赵宇玮许耀 Carl Hirschie johnson jan kol.r 西北大学生命科学学院陕西省生物技术重点实验室西安710069 Department of Biology Box1812-BVanderbilt University Institute of Experimental Botany Academy of Sciences of the Czech Republic

通过根癌农杆菌(含植物表达载体YXu55)介导的转化技术,将褪黑素生物合成酶-芳烷基胺N-乙酰转移酶(Arylalkylamine N-acetyltransferase,AANAT)与羟基吲哚O-甲基转移酶(Hydroxyindole O-methyltransferase,HIOMT)基因导入到烟草(秦烟95)中。对所获得的庆大霉素抗性烟草株系进行Southern blotting和rT-PCr分子生物学检测,结果表明,AANAT-HIOMT基因已成功地整合到烟草基因组中,并且可以在mrNA水平上进行转录。用反相高效液相色谱法(rP-HPLC)测定转化株系的褪黑素含量表明,转AANAT-HIOMT基因烟草株系的褪黑素含量均明显高于pZP122(不含AANAT和HIOMT基因的空白质粒)转基因株系和未转基因的对照植株,证明AANAT-HIOMT基因在转基因植株中的表达增强了褪黑素的合成能力。对不同株系抗氧化系统的部分指标进行了测定,并与其亲本对照植株比较,发现AANAT-HIOMT基因在转基因植物中的表达引起超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性增加,谷胱甘肽(GSH)浓度以及总抗氧化能力升高,且没有引起膜脂质过氧化物丙二醛(MDA)的变化,说明转基因烟草抗氧化潜能得到提高。

关键词：烟草褪黑素褪黑素合成酶基因遗传转化抗氧化

Lignocellulose as an insoluble fiber source in poultry nutrition:a review

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journal of Animal Science and Biotechnology 2021年第4期12卷 1237-1251页

作者： Ilen röhe jürgen Zentek Department of Veterinary Medicine Institute of Animal NutritionFreie Universität Berlin14195 BerlinGermany

Extensive research in recent years into the use of various fiber sources in poultry nutrition has led to the perception that dietary fiber is more than a simple diet *** studies showed that the feeding of insoluble fiber sources such as oat hulls,sunflower hulls or wood shavings may affect digestive physiology and function improving chickens health and growth *** this context,the effect of lignocellulose as an insoluble dietary fiber source is increasingly being *** is a component of plant cell walls and consists mainly of the insoluble carbohydrate polymers cellulose and hemicelluloses as well as the phenolic polymer *** is chemically and physicochemically different from other insoluble fiber sources and thus possibly has different effects on poultry compared to traditional fiber *** studies investigated the effect of dietary lignocellulose on growth performance,nutrient digestibility,gastrointestinal tract development and intestinal microbiota in broilers and laying *** differed in terms of feed formulation and lignocellulose inclusion level as well as products of different suppliers were *** results obtained are inconsistent;beneficial,indifferent or detrimental effects of feeding lignocellulose were observed,so that a final assessment of lignocellulose as a“novel”insoluble fiber source is *** review article summarizes the results of studies in connection with the feeding of lignocellulose to poultry,compares them with those that have used other insoluble fiber sources and illuminates the possible mechanisms of action.

关键词： Fiber Growth performance Gut health Gut morphology Lignocellulose Microbiota Nutrient digestibility Poultry

Considerations for effective ground support in evaporites

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International journal of Mining Science and Technology 2019年第1期29卷 113-118页

作者： j.r.Nopola C.A.Vining rESPEC

Evaporites, such as salt and potash, pose unique problems to ground-support designs that are not encountered in other rock types. Evaporites are subject to continual creep and no amount of ground support can successfully arrest this process. Common ground-support techniques that are useful for most rock types may reduce the effective life of bolts in evaporite mines and create unseen hazards. A different approach to ground support must be applied to provide long-term support in areas where high creep rates are present. The goal of effective ground-support designs in these situations is not to contain and prevent the rock from moving; rather, the ground-support design must be able to move along with the rock and contain any fully detached slabs until additional remediation measures can be *** most appropriate ground-support designs will consider the expected movement of the rock and the duration that the area needs to remain accessible.

关键词： Ground support Ground control rock mechanics And salt mechanics

Strain gradient plasticity: energetic or dissipative?

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Acta Mechanica Sinica 2015年第4期31卷 465-472页

作者： N.A.Fleck j.r.Willis Department of Engineering University of Cambridge Department of Applied Mathematics and Theoretical Physics University of Cambridge

Abstract For an infinite slab of strain gradient sensitive material subjected to plane-strain tensile loading, compu- tation established and analysis confirmed that passivation of the lateral boundaries at some stage of loading inhibits plastic deformation upon further loading. This result is not surprising in itself except that, remarkably, if the gradient terms contribute to the dissipation, the plastic deformation is switched off completely and only resumes at a clearly defined higher load, corresponding to a total strain ec, say. The analysis presented in this paper confirms the delay of plastic deformation following passivation and determines the exact manner in which the plastic flow resumes. The plastic strain rate is continuous at the exact point ec of resumption of plastic flow and, for the first small increment Ae = e - ec in the imposed total strain, the corresponding increment in plastic strain, AeP, is proportional to （Ae）2. The constant A in the relation AeP（0） = A（Ae）2, where AeP（0） denotes the plastic strain increment at the centre of the slab, has been determined explicitly; it depends on the hardening modulus of the material. The presence of energetic gradient terms has no effect on the value of ec unless the dissipative terms are absent, in which case passivation reduces the rate of plastic deformation but introduces no delay. This qualitative effect of dissipative gradient terms opens the possibility of experimen- tal discrimination of their presence or absence. The analysisemploys an incremental variational formulation that is likely to find use in other problems.

关键词： Strain gradient plasticity Boundary passivation Incremental variational principle

SECOND-OrDEr INTErACTION OF IrrEGULAr WAVES WITH A TrUNCATED COLUMN

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Acta Mechanica Sinica 1997年第2期13卷 130-142页

作者： j.B.Huang r.EatockTaylor Department of Engineering Science University of OxfordParks RoadOxfordOX1 3PJUK

A complete semi-analytical solution is obtained for second-order diffraction of plane bichromatic waves by a fixed truncated circular *** fluid domain is divided into interior and exterior *** the exterior region,the second-order velocity potential is expressed in terms of‘locked-wave’and‘free-wave’ components,both are solved using Fourier and eigenfunction *** re- sulting‘locked wave’potential is expressed by one-dimensional Green's integrals with oscillating *** order to increase computational efficiency,the far-field part of the integrals are carried out *** in both regions are matched on the interface by the potential and its normal derivative continuity *** on the present approach,the sum-and difference-frequency potentials are efficiently evaluated and are used to generate the quadratic transfer functions which correlates the incident wave spectrum with second-order forcing spectrum on the *** sum-frequency QTFs for a TLP column are present,which are compared for some frequency pairs with those from a fully numerical *** agreement has been *** spectra for a case study TLP column,generated using the semi-analytical solution are *** given are the results for nonlinear wave field around the column.

关键词： marine hydrodynamics nonlinear wave force wave-structure interaction second-order wave diffraction

Performance investigation of artificial intelligence based controller for three phase four leg shunt active filter

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Frontiers in Energy 2015年第4期9卷 446-460页

作者： j. jAYACHANDrAN r. MUrALI SACHITHANANDAM Department of Electrical and Electronics Engineering SASTRA University Thanjavur 613401 India

In this paper, the choice of power quality compensator is a DSTATCOM which constitutes a three phase four leg voltage source converter （VSC） with a DC capacitor. The control strategy proposed for the DSTAT- COM is a neural network based one cycle control （OCC）. This control strategy involves neural network block, digital circuits and linear elements, which eliminates the sensors required for sensing the load current and coupling inductor current in addition to the multiplier employed in the conventional method. The calculation of harmonic and reactive currents for the reference current generation is also eliminated, thus minimizing the complexity in the control strategy. The control strategy mitigates harmonic/reactive currents, ensures balanced and sinusoidal source current from the supply mains that are nearly in phase with the supply voltage, compensates neutral current, and maintains voltage across the capacitor under unbalanced source and load conditions. The performance of the DSTATCOM with the proposed artificial neural network （ANN） controllers is validated and investigated through simulations using Matlab software. The simulation results prove the efficacy of the proposed neural network based control strategy under varying source and load conditions.

关键词： neural network DSTATCOM neutral currentmitigation total harmonic distortion (THD) three phasefour wire distribution system unbalanced and/or distortedsource

THE DErIVATIVE PATCH INTErPOLATING rECOVErY TECHNIQUE FOr FINITE ELEMENT APPrOXIMATIONS

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journal of Computational Mathematics 2004年第1期22卷 113-122页

作者： TieZhang Yan-pingLin r.j.Tait DepartmentofMathematics NortheasternUniversityShenyang110006China DepartmentofMathematics UniversityofAlbertaAlbertaCanadaT6G2G1

A derivative patch interpolating recovery technique is analyzed for the finite element approximation to the second order elliptic boundary value problems in two dimensional *** is shown that the convergence rate of the recovered gradient admits superc onvergence on the recovered subdomain, and is two order higher than the optimal global convergence rate (ultracovergence) at an internal node point when even order finite element spaces and local uniform meshes are used.

关键词： Derivative recovery Finite element Ultraconvergence