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The Modeling of Production and Economic Indicators in Suckler Cows Herds

Journal of Agricultural Science and Technology(A) 2014年第1期4卷 93-101页

作者： andrej koleno Jan fluba Zuzana Krupova Monika Michalickova Ondrej Debreceni Department of Quality Control and Quality Management RAJO a.s. Studen6 35 Bratislava 823 55 Slovak Republic Institute of Animal Breeding and Product Quality Animal Production Research Centre Nitra Hlohoveck~ 2 Lu2ianky 951 41Slovak Republic Department of Genetics and Breeding of Farm Animals Institute of Animal Science Praha Uhrineves Pratelstvi 815 104 00Czech Republic Faculty of Agrobiology and Food Resources Slovak University of Agriculture in Nitra Tr. A. Hlinku 2 Nitra 949 76 SlovakRepublic

The aim of this study was to analyse the most important factors affecting the profitability of suckler cows herds in Slovakia in 2010. The economic models were used to verify whether the suckler cows farming is profitable without subsidies in the current production conditions in Slovakia as well as their optimal location in the agricultural natural conditions of Slovakia from the perspective of economic efficiency. The breeding of cattle, mainly for the beef meat production, has long been unprofitable as it is apparent also from the analysis of several studies. In the model without inclusion of subsidies, it was calculated that the suckler cows farming is unprofitable at the current production parameters and realization prices of calves. The losses per cow and year were ranged from -240ε in the model by using a combination of the maximum threshold values of input parameters to -818ε by using a combination of the minimum threshold values of the input parameters. In the models including of subsidies amount of loss and/or profit per cow and year varied depending on the input parameters mainly on natality, average daily gain, the realization price of calves and the level of subsidies provided to breeder as well. The economic results are ranged from -277ε to 724ε per cow and year. From economical as well as production point of view, the most appropriate agricultural natural regions for suckler cows farming in Slovakia are upland and highland regions.

关键词： Economics beef production suckler cows subsidies profit.

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Site-specific patterns of fine root biomass formation across European coniferous forests

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FOREST ECOSYSTEMS 2025年第1期12卷 104-111页

作者： Karpechko, Yury Karpechko, Anna Tuyunen, andrej Russian Acad Sci Forest Res Inst Karelian Res Ctr 11 Pushkinskaya St Petrozavodsk 185910 Karelia Russia

Fine roots play a crucial role in the biogeochemical cycles of terrestrial ecosystems. Patterns of fine roots biomass formation for broad geographical areas are still unclear. We use published estimates of characteristics of European pine and spruce stands to determine their productivity and calculate the needle biomass. Then, the relationship between the fine-root:needle biomass ratio of European pine and spruce forests and the stand quality index, which is a proxy of soil fertility, was determined. We show that a rise in soil fertility is accompanied by a decrease in this ratio. Moving from the northern edge of the boreal zone southwards, with the related rise in air and soil temperatures, we see a decline in the mass ratio of fine roots and needle. The change in the fine-root:needle biomass ratio is controlled by the change in specific water uptake by roots, which is related to the osmotic pressure of the solution in the absorbing root's central vascular cylinder. The fine-root:needle ratio does not vary among stands of the same age if the stand quality index and the geographical latitude (a proxy of air and soil temperatures) are constant. These findings may be useful for further in-depth analysis of forest ecosystem functioning in Europe.

关键词： Fine-root:needle biomass ratio Stand quality class Soil fertility Latitudinal variation Allometric equation

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Site-specific patterns of fine root biomass formation across European coniferous forests

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Forest Ecosystems 2025年第1期 104-111页

作者： Yury Karpechko Anna Karpechko andrej Tuyunen Forest Research Institute of the Karelian Research Centre of the Russian Academy of Sciences

Fine roots play a crucial role in the biogeochemical cycles of terrestrial *** of fine roots biomass formation for broad geographical areas are still *** use published estimates of characteristics of European pine and spruce stands to determine their productivity and calculate the needle ***,the relationship between the fine-root:needle biomass ratio of European pine and spruce forests and the stand quality index,which is a proxy of soil fertility,was *** show that a rise in soil fertility is accompanied by a decrease in this *** from the northern edge of the boreal zone southwards,with the related rise in air and soil temperatures,we see a decline in the mass ratio of fine roots and *** change in the fine-root:needle biomass ratio is controlled by the change in specific water uptake by roots,which is related to the osmotic pressure of the solution in the absorbing root's central vascular *** fine-root:needle ratio does not vary among stands of the same age if the stand quality index and the geographical latitude (a proxy of air and soil temperatures) are *** findings may be useful for further in-depth analysis of forest ecosystem functioning in Europe.

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Numerical and experimental analyses of a stirred vessel for a large volumetric flow rate of sparged air

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2304-2312页

作者： andrej Bombac Jernej Pirnar Laboratory for Fluid Dynamics and Thermodynamics Faculty of Mechanical EngineeringUniversity of LjubljanaAskerceva 61000 LjubljanaSlovenia

Computational fluid dynamics(CFD)and experimental analyses of some of the basic characteristics of air sparging in a tall stirred vessel equipped with a three-stage impeller are *** impeller was assembled from a radial ABT impeller as the lower,a turbine 6 PBT45 as the middle and an axial Scaba-type 3SHP1 impeller as the *** the impellers were of the same diameter,i.e.,225 mm,while the vessel diameter was 450 *** impeller’s rotational speed was 178 r·*** aeration regime was established with an air volumetric flow rate of 28.3 m3·*** the best of our knowledge,this study is the first to consider the very high gassing rate by means of CFD in a tank stirred by three-stage axial/radial *** numerical simulation was performed using the ANSYS Fluent(R17.2,2016)code for solving the governing equations of fluid dynamics in single-and multi-phase *** discussing the bubble size distribution,a discrete population balance model(PBM)was *** CFD,the stirring power and the total void fraction(the total gas holdup)were *** results were in good agreement with the measured values using a laboratory experimental device.

关键词： Mixing Stirred vessel Aeration Multiple stirrer High gassing rate Local void fraction

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Muscular abnormalities in liver cirrhosis

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World Journal of Gastroenterology 2021年第29期27卷 4862-4878页

作者： andrej Hari Department of Gastroenterology and Hepatology General Hospital CeljeCelje 3000SavinjskaSlovenia

Sarcopenia is becoming a well-established player in evaluating patients with chronic liver *** regarding its clinical significance and consequences in the course of liver disease have been growing;many of the data support the idea that it impacts decompensation event frequency,prolonged hospitalization,and mortality,as well as providing the possibility to better prioritize patients on lists awaiting liver *** assessing the whole clinical scope of the field,which includes malnutrition and frailty,as well as the complete spectrum of muscle mass,strength,and function,it becomes clear that a well-founded approach in everyday clinical practice is *** this respect,this article attempts to unveil the most recently published data regarding possible methods and modalities that could be used to diagnose sarcopenia as early as possible,along with the required accuracy and *** the most important field discoveries to data that need further clarification,the merits and weaknesses of the very diverse existing evaluation methods are ***,a critical overview is given,in an attempt to discern study lines of importance from those that could pose further ambiguity for the *** author also poses relevant questions that remain unanswered but are of clinical importance in the field.

关键词： Sarcopenia Liver cirrhosis Frailty Muscle strength Nutrition indices Risk factors

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Distortion performance of underwater acoustic mobile networks

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Journal of Ocean Engineering and Science 2018年第4期3卷 382-389页

作者： andrej Stefanov Faculty of Engineering IBU SkopjeMacedonia

The paper considers the distortion performance of mobile underwater acoustic *** network is composed of autonomous underwater vehicles(AUV’s)that utilize multihop transmissions to route the information through the *** mobility model is direction *** distortion is evaluated in the context of an independent identically distributed(i.i.d.)Gaussian source and single description *** AUV-to-AUV channel experiences frequency dependent path loss and Ricean fading,as well as interference from other network *** examples illustrate the distortion performance.

关键词： network mobile underwater

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The effect of growth conditions on the relationship between fine root and foliage biomass

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Journal of Forestry Research 2022年第5期33卷 1585-1591页

作者： Yury Karpechko Anna Karpechko andrej Tuyunen Forest Research Institute of the Karelian Research Centre of the Russian Academy of Sciences 11 Pushkinskaya St.PetrozavodskKareliaRussia 185910

This article examines the physiological relationships between fine roots and foliage, and how their biomass ratio correlates with changes in stand quality class. The biomass of fine roots ≤ 3 mm in diameter of spruce stands in the Republic of Karelia (Northwest Russia) was determined by the soil monolith method. Foliage biomass was calculated using a previously designed technique from the standing stock, average height and quality class of the stand. A relation between fine-root: foliage biomass ratio and stand quality class (representing soil fertility) has been established. The closest correlation between fine-root: foliage biomass ratio and stand quality based on soil fertility was for the 1-2 mm root fraction. Analysis of the water flux balance in the trees revealed a correlation between fine-root: foliage ratio and the ratio of the specific volume of transpiration by the stand to the specific volume of water uptake from the soil by roots. Theoretical explanations for the decrease in fine-root: foliage biomass ratios with increasing stand quality class are offered.

关键词： Fine-root biomass Foliage biomass Stand quality class Soil fertility

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Recently deepened insights regarding Mg corrosion and advanced engineering applications of Mg alloys

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Journal of Magnesium and Alloys 2023年第11期11卷 3948-3991页

作者： Guang-Ling Song andrej Atrens Department of Ocean Science and Engineering Southern University of Science and Technology1088 Xueyuan BoulevardShenzhen 518055China The University of Queensland School of Mechanical and Mining EngineeringCentre for Advanced Materials Processing and Manufacturing(AMPAM)St LuciaQld 4072 Australia State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen University422 S.Siming RdXiamen 361005China

This review summarizes recent insights into the Mg corrosion mechanism, clarifies many critical controversial points regarding the Mg corrosion behaviour, and updates some efforts made to extend the industrial application of Mg alloys. Based on the new understandings gained so far, future research directions are also suggested in the review. This review has the following logic. The first section "1. Scope"is a consolidation of the new understandings or developments regarding the Mg corrosion mechanism and the new applications for Mg alloys. It also highlights some key points for the review. The second section "2. Widely accepted knowledge" briefly summarizes the general understanding of Mg corrosion gained so far, which acts as the foundation for the following sections. The third section "3. Recently deepened insights" mainly briefs on some new insights into Mg corrosion phenomena based on recent findings. Different interpretations on the corrosion behaviours are comprehensively discussed in the fourth section "4. Controversial points" and the conclusions are drawn in the subsection"4.5 Clarified points". Apart from the fundamental understandings, various efforts in the application of Mg alloys are presented in the fifth section "5. New applications". Following the research tendency as indicated in the review, prioritized research areas are suggested in "*** directions". The review is concluded with "7. Concluding remarks" at last.

关键词： Mg Corrosion Hydrogen Anode Intelligentization

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On the stability of small-scale ballooning modes in axisymmetric mirror traps

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Plasma Science and Technology 2022年第1期24卷 8-17页

作者： Igor KOTELNIKOV andrej LIZUNOV Qiusun ZENG Budker Institute of Nuclear Physics SB RAS Novosibirsk 630090Russia Novosibirsk State University Novosibirsk 630090Russia Institute of Nuclear Energy Safety Technology HFIPS CAS Hefei 230031People's Republic of China

It is shown that a steepening of the radial plasma pressure profile leads to a decrease in the critical value of beta,above which,small-scale balloon-type perturbations in a mirror trap become *** may mean that small-scale ballooning instability leads to a smoothing of the radial plasma *** critical beta values for the real magnetic field of the gas-dynamic trap and various plasma pressure radial profiles was also *** a plasma with a parabolic profile critical beta is evaluated at the level of 0.72.A previous theoretical prediction for this trap was almost two times lower than maximal beta 0.6 achieved experimentally.

关键词： mirror trap ballooning modes critical beta

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Structural properties of effective potential model by liquid state theories

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Chinese Physics B 2010年第11期19卷 165-173页

作者：向远涛 andrej Jamnik 杨开巍 School of Physics Science and Technology Central South University University of Ljubljana Faculty of Chemistry and Chemical TechnologyAkereva 5SI-1001 LjubljanaSlovenia

This paper investigates the structural properties of a model fluid dictated by an effective inter-particle oscillatory potential by grand canonical ensemble Monte Carlo （GCEMC） simulation and classical liquid state theories. The chosen oscillatory potential incorporates basic interaction terms used in modeling of various complex fluids which is composed of mesoscopic particles dispersed in a solvent bath, the studied structural properties include radial distribution function in bulk and inhomogeneous density distribution profile due to influence of several external fields. The GCEMC results are employed to test the validity of two recently proposed theoreticai approaches in the field of atomic fluids. One is an Ornstein-Zernike integral equation theory approach; the other is a third order ＋ second order perturbation density functional theory. Satisfactory agreement between the GCEMC simulation and the pure theories fully indicates the ready adaptability of the atomic fluid theories to effective model potentials in complex fluids, and classifies the proposed theoretical approaches as convenient tools for the investigation of complex fluids under the single component macro-fluid approximation.

关键词： atomic fluid classical ensemble

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