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Pharmacological Control of Estrus in Tropical Cattle,an Economical Assessment of Different Synchronization Protocols

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Open Journal of Veterinary Medicine 2012年第3期2卷 151-157页

作者： Juan J.molina ivan molina Alejandro Jimenez Carlos S.Galina Juan J.Romero Asesor Laboratorios Intervet Schering Plough BogotaColombia Director Tecnico Agropecuaria Las Tinajas S.A. BogotaColombia Departamento de Reproduccion Facultad de Medicina Veterinaria y ZootecniaUniversidad Nacional Autonoma de MexicoMexico CityMexico Programa de Investigacion en Medicina Poblacional Escuela de Medicina VeterinariaUniversidad NacionalHerediaCosta Rica Campus Benjamín Nunez HerediaCosta Rica

To compare the fertility results and to assess the cost-effectiveness of several synchronization protocols applied under the conditions of beef cattle enterprises in Colombia, 1658 multiparous zebu crossbred cows mostly Brahman and Nelore ranging between 2 - 6 parities were used. Five protocols of pharmacological treatments varying in hormones used, dosage and the time of application were tested. All cows were inseminated at 52 h by appointment. Pregnancy diagnosis was undertaken over 45 d after insemination by rectal palpation. The total cost per cow and the total cost per gestation, for each protocol, were calculated. Taking a herd of one-hundred cows as baseline for calculations, it was estimated the cost of the total amount of pregnancies possibly obtained in each protocol;then, the excess between the costs of a pregnant cow and the cost of a treated cow was estimated. Additionally, the costs due to cows empty after four services were calculated. A total of 874 pregnancies were registered (52.7%), with pregnancies per protocol varying between 46.9% and 66.2% (p < 005). The cost per treated cow, varied between $64.08 and $97.47 and the cost per gestation from $126.01 to $177.26, without association between the cost of the treatment and the pregnancy rate. Protocol A was the best cost-effective with the lowest additional costs, the lowest amount of open days (2107.7 to 2231.7 d) and IA straws (average = 134), with an additional costs of $6940.00. Synchronization of estrus using pharmacological products seems to have a place in the management of cattle;however, caution should be called upon a careful assessment both from the part of the farm and the professional in charge of the enterprise to avoid using the technique indiscriminatively thus propitiating the use of a method that might not be cost efficient.

关键词： Tropics Bos Indicus Cost-Benefit Estru Synchronization

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现代网球技战术名家精华如何运用好中场技术

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网球天地 2003年第12期 64-65页

作者： ivan molina 张伟

现代网球运动需要运动员不只是底线,还包括中场,都应具备完善的技术和进攻战术。现代优秀选手,可以通过强有力的底线进攻或发球上网等技术,来迫使对方处于被动。但是如果此时,这名选手不能用第一次或第二次截击来获得该分的话,他将失去... 详细信息

现代网球运动需要运动员不只是底线,还包括中场,都应具备完善的技术和进攻战术。现代优秀选手,可以通过强有力的底线进攻或发球上网等技术,来迫使对方处于被动。但是如果此时,这名选手不能用第一次或第二次截击来获得该分的话,他将失去先前的主动局面。在这样的比赛过程中,该得分而没能得分的选手.往往会逐渐失去进攻性和信心,最终导致其选择消极战术。

关键词：反弹球截击球运动员教练员网球运动进攻战术击球方法精华进攻性协调性

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Search for microglia-specific peptides:advances in the discovery toolbox

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Neural Regeneration Research 2025年第2期20卷 471-472页

作者： ivan Sarabia Kyle M.Koss Department of Surgery University of ArizonaTucsonAZUSA

Uncontrolled and chronic inflammatory states in the central nervous system(CNS)are the hallmark of neurodegenerative pathology and every injury or stroke-related *** key mediators of these neuroinflammatory states are glial cells known as microglia,the resident immune cell at the core of the inflammatory event,and astroglia,which encapsulate inflammatory insults in proteoglycan-rich scar *** gliotic scar blocks significant portions of healthy axonal networking,preventing *** most neuroinflammation is exclusively based on the responses of said microglia,their phenotypes are suggested to follow those of macrophages;M1 and M2 are opposites of pro-and ***,microglial phenotypes have been identified to be on an inflammatory spectrum encompassing developmental,homeostatic,and reparative behaviors as opposed to their ability to affect devastating cell death cascades and scar tissue formation.

关键词： inflammation pathology death

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合理运用比赛分析法

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网球天地 2005年第3期 58-58页

作者： ivan molina 张伟哥伦比亚参加ITF团体巡回赛教练

教练员在观看青少年或职业选手的网球比赛时,都会对运动员在场上的表现进行分析和评估。这将有助于加深对比赛的正确认识,以便及时地发现运动员自身明显的优缺点,对改善今后比赛中的表现起到一定的作用。

关键词：比赛分析法合理运用运动员教练员技术统计身体机能身体素质预判能力评价分析心理能力

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Experimental control of optical helicity in nanophotonics

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Light(Science & Applications) 2014年第1期3卷 166-172页

作者： Nora Tischler ivan Fernandez-Corbaton Xavier Zambrana-Puyalto Alexander Minovich Xavier Vidal Mathieu L Juan Gabriel molina-Terriza ARC Centre for Engineered Quantum Systems Department of Physics&AstronomyMacquarie UniversitySydneyNSW 2109Australia Department of Physics&Astronomy Macquarie UniversitySydneyNSW 2109Australia Nonlinear Physics Centre and Centre for Ultrahigh-bandwidth Devices for Optical Systems(CUDOS) Research School of Physics and EngineeringThe Australian National UniversityCanberraACT 0200Australia

An analysis of light–matter interactions based on symmetries can provide valuable insight,particularly because it reveals which quantities are conserved and which ones can be transformed within a physical *** this context,helicity can be a useful addition to more commonly considered observables such as angular *** question arises how to treat helicity,the projection of the total angular momentum onto the linear momentum direction,in practical *** this paper,we put forward a simple but versatile experimental treatment of *** then apply the proposed method to the scattering of light by isolated cylindrical nanoapertures in a gold *** allows us to study the helicity transformation taking place during the interaction of focused light with the *** particular,we observe from the transmitted light that the scaling of the helicity transformed component with the aperture size is very different to the direct helicity component.

关键词： helicity nanoaperture nanophotonics optics symmetry

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REGULARITY FOR A GENERALIZED JEFFREY'S INTEGRAL MODEL FOR VISCOELASTIC FLUIDS

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Acta Mathematica Scientia 2015年第6期35卷 1251-1284页

作者： ivan SOUKUP Department of Numerical Mathematics Faculty of Mathematics and PhysicsCharles University in Prague

We prove a local existence of a strong solution v ：Ω×T→R^3 for a system of nonlinear integrodifferential equations describing motion of an incompressible viscoelastic fluid using standard mathematical tools. The problem is considered in a bounded, smooth domain ΩСR^3 with a Dirichlet boundary condition and a standard initial condition.

关键词： integral model viscoelastic fluid strong solution

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Topology of Moment-Angle Manifolds Arising from Flag Nestohedra

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Chinese Annals of Mathematics,Series B 2017年第6期38卷 1287-1302页

作者： ivan LIMONCHENKO School of Mathematical Sciences Fudan UniversityShanghai 200433China.

The author constructs a family of manifolds, one for each n ≥ 2, having a nontrivial Massey n-product in their cohomology for any given n. These manifolds turn out to be smooth closed 2-connected manifolds with a compact torus Tm-action called momentangle manifolds ZP, whose orbit spaces are simple n-dimensional polytopes P obtained from an n-cube by a sequence of truncations of faces of codimension 2 only(2-truncated cubes). Moreover, the polytopes P are flag nestohedra but not graph-associahedra. The author also describes the numbers β^(-i,2(i+1))(Q) for an associahedron Q in terms of its graph structure and relates it to the structure of the loop homology(Pontryagin algebra)H_*(?ZQ), and then studies higher Massey products in H*(ZQ) for a graph-associahedron Q.

关键词： Moment-angle manifold Flag nestohedra Stanley-Reisner ring Masseyproducts Graph-associahedron

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Experimental and calculated liquid-liquid interfacial tension in demixing metal alloys

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Rare Metals 2006年第5期25卷 452-456页

作者： Walter Hoyer ivan Kaban Institute of Physics Chemnitz University of Technology D-09107 ChemnitzGermany

Liquid-liquid interracial tension in binary and temary Al-based monotectic systems has been determined experimentally with a tensiometric method in a wide temperature interval. The temperature dependence of the interfacial tension is well described by a power law function of the type σαβ - （1 - T/Tc）δ with the critical exponent δ= 1.3 and a critical temperature Tc. Theoretical models describing the liquid-liquid interface in monotectic alloys and their applicability for calculation of the interfacial tension and its temperature dependence in binary systems are considered.

关键词： immiscible systems Al-based alloys interracial tension

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Effects of pre-existing cracks and infillings on strength of natural rocks--Cases of sandstone, argillite and basalt

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第6期12卷 1333-1338页

作者： Chen Cui ivan Gratchev School of Engineering Griffith UniversityGold CoastAustralia

This study aims to examine the influence of pre-existing discontinuities on the strengths of four natural rocks of different origins.A series of unconfined compression tests was performed on specimens of two types of sandstones,argillite and basalt that contain open and filled *** was found that the presence of cracks tends to decrease the overall strength for all studied rocks;however,the magnitude of strength reduction is related to the property of *** larger strength decrease was observed for the relatively harder argillite and basalt,compared to the softer *** was also found that the infill material could increase the strength of rock specimens,while the obtained strength depended on the characteristics of the fill material.

关键词： Pre-existing crack Rock strength Infill material Laboratory test

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Purinergic Modulation of Activity in the Developing Auditory Pathway

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Neuroscience Bulletin 2020年第11期36卷 1285-1298页

作者： Sasa Jovanovic ivan Milenkovic School of Medicine and Health Sciences Carl von Ossietzky University Oldenburg26129 OldenburgGermany

Purinergic P2 receptors,activated by endogenous ATP,are prominently expressed on neuronal and nonneuronal cells during development of the auditory periphery and central auditory *** the mature cochlea,extracellular ATP contributes to ion homeostasis,and has a protective function against noise ***,we focus on the modulation of activity by extracellular ATP during early postnatal development of the lower auditory *** mammals,spontaneous patterned activity is conveyed along afferent auditory pathways before the onset of acoustically evoked signal *** this critical developmental period,inner hair cells fire bursts of action potentials that are believed to provide a developmental code for synaptic maturation and refinement of auditory circuits,thereby establishing a precise tonotopic *** ATP-release triggers such patterned activity by raising the extracellular K+concentration and contributes to firing by increasing the excitability of auditory nerve fibers,spiral ganglion neurons,and specific neuron types within the auditory brainstem,through the activation of diverse P2 *** review recent studies that provide new models on the contribution of purinergic signaling to early development of the afferent auditory ***,we discuss potential future directions of purinergic research in the auditory system.

关键词： Purinergic signaling Auditory system Development Cochlea Spiral ganglion Auditory brainstem

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