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Association between heat stress and oxidative stress in poultry;mitochondrial dysfunction and dietary interventions with phytochemicals

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Journal of Animal Science and Biotechnology 2017年第1期8卷 1-14页

作者： Abdollah Akbarian Joris Michiels Jeroen Degroote Maryam Majdeddin abolghasem golian Stefaan De Smet Department of Animal Production Laboratory for Animal Nutrition and Animal Product QualityGhent UniversityProefhoevestraat 10Melle 9090Belgium Centre of Excellence in the Animal Science Department Ferdowsi University of MashhadP.O.Box:91775-1163MashhadIran Department of Applied Biosciences Ghent UniversityValentin Vaerwyckweg 1Ghent 9000Belgium

Heat as a stressor of poultry has been studied extensively for many decades; it affects poultry production on a worldwide basis and has significant impact on well-being and production. More recently, the involvement of heat stress in inducing oxidative stress has received much interest. Oxidative stress is defined as the presence of reactive species in excess of the available antioxidant capacity of animal cells. Reactive species can modify several biologically cellular macromolecules and can interfere with cell signaling pathways. Furthermore, during the last decade, there has been an ever-increasing interest in the use of a wide array of natural feed-delivered phytochemicals that have potential antioxidant properties for poultry. In light of this, the current review aims to（1） summarize the mechanisms through which heat stress triggers excessive superoxide radical production in the mitochondrion and progresses into oxidative stress,（2） illustrate that this pathophysiology is dependent on the intensity and duration of heat stress,（3） present different nutritional strategies for mitigation of mitochondrial dysfunction, with particular focus on antioxidant *** stress that occurs with heat exposure can be manifest in all parts of the body; however, mitochondrial dysfunction underlies oxidative stress. In the initial phase of acute heat stress, mitochondrial substrate oxidation and electron transport chain activity are increased resulting in excessive superoxide production. During the later stage of acute heat stress, down-regulation of avian uncoupling protein worsens the oxidative stress situation causing mitochondrial dysfunction and tissue damage. Typically, antioxidant enzyme activities are upregulated. Chronic heat stress, however, leads to downsizing of mitochondrial metabolic oxidative capacity, up-regulation of avian uncoupling protein, a clear alteration in the pattern of antioxidant enzyme activities, and depletion of antioxidant reserve

关键词： Antioxidant enzymes Avian uncoupling protein Electron transport chain Flavonoids Heat Stress Mitochondrion Oxidative stress Poultry

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A New Insight into Energy Distribution of Electrons in Fuel-Rod Gap in VVER-1000 Nuclear Reactor

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Plasma Science and Technology 2015年第6期17卷 441-447页

作者： Fereshteh golian Ali PAZIRANDEH Saeed MOHAMMADI Payam Noor University Science & Research Branch Islamic Azad University

In order to calculate the electron energy distribution in the fuel rod gap of a VVER- 1000 nuclear reactor, the Fokker-Planck equation （FPE） governing the non-equilibrium behavior of electrons passing through the fuel-rod gap as an absorber has been solved in this paper. Besides, the Monte Carlo Geant4 code was employed to simulate the electron migration in the fuel-rod gap and the energy distribution of electrons was found. As for the results, the accuracy of the FPE was compared to the Geant4 code outcomes and a satisfactory agreement was found. Also, different percentage of the volatile and noble gas fission fragments produced in fission reactions in fuel rod, i.e. Krypton, Xenon, Iodine, Bromine, Rubidium and Cesium were employed so as to investigate their effects on the electrons＇ energy distribution. The present results show that most of the electrons in the fuel rod＇s gap were within the thermal energy limitation and the tail of the electron energy distribution was far from a Maxwellian distribution. The interesting outcome was that the electron energy distribution is slightly increased due to the accumulation of fission fragments in the gap. It should be noted that solving the FPE for the energy straggling electrons that are penetrating into the fuel-rod gap in the VVER-1000 nuclear reactor has been carried out for the first time using an analytical approach.

关键词： plasma electron energy distribution function Langevin approach based onFokker-Planck equation Geant4 Monte Carlo code

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Advantages of employing multilevel monitoring wells for design of tunnels subjected to multi-aquifer alluvial

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Journal of Mountain Science 2021年第1期18卷 219-232页

作者： Mohsen golian Ebrahim SHARIFI TESHNIZI Hamed TAVASOLI ROSTAMI Homayoon KATIBEH Mario PARISE Masoud MAHDAD Habib SAADAT Mehdi ABBASI Mahshid EBAD ARDESTANI Tehran Science and Research Branch Islamic Azad UniversityTehran ***Iran Department of Geology Faculty of SciencesFerdowsi UniversityMashhad 917751436Iran Mining and Metallurgical Engineering Department Amirkabir University of Technology(Tehran Polytechnic)Tehran ***Iran Earth and Environmental Sciences Department University Aldo MoroBari 70121Italy Iran University of Science and Technology Tehran ***Iran Shiraz University Shiraz ***Iran

For tunnels being excavated through multiple knowledge of the aquifers’hydraulic head becomes essential for determining groundwater inflow into the tunnel and analyzing its stability,specifically using multilevel monitoring *** the multi-aquifer alluvial section of the Glas tunnel(Iran),since the hydraulic head calculations were based on the data obtained from single-piezometer boreholes,the excavation risk was assessed to be at high level and the tunnel seemed to be unstable,thus an incorrect conclusion was derived from the misleading *** take cost mitigation measures into account,it was necessary to calculate the hydraulic head at tunnel level *** installing nested and clustered wells the mean hydraulic head was measured to be 70 m,significantly different from the 90 m previously determined by *** the updated value,the groundwater inflow and bulkhead load,formerly calculated as 0.65 m^(3)/s and 9.5 bars,were determined to be 0.49 m^(3)/s and 7.5 bars,respectively.

关键词： Nested wells Clustered wells Hydraulic head Pumping test Mechanized tunneling Iran

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高温高超音速流动中的边界层排移和前缘纯度效应(续)

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力学季刊 1966年第3期 63-80页

作者：郑显基 J.Gordon Hall T.C.golian A.Hertzberg 高流北

三、平板流动的实验研究在前面第2节中,我们对于绕细长体的高超音速流动中的钝度、粘性互涉和物面角度影响的一般问题进行了理论研究.特别是在第2.2节中,给出了关于一般平板问题的特解.此外,在第2.3节中,高超音速粘性流相似律己被推广... 详细信息

三、平板流动的实验研究在前面第2节中,我们对于绕细长体的高超音速流动中的钝度、粘性互涉和物面角度影响的一般问题进行了理论研究.特别是在第2.2节中,给出了关于一般平板问题的特解.此外,在第2.3节中,高超音速粘性流相似律己被推广到包括前缘钝度的影响.本节将描述相应的实验方案,这些方案是为了取得实验数据以验证第2.3节中的推广相似律和对第2.2节中理论解的预测进行比较而设计的.实验的详细结果将在第四节中讨论.

关键词：所得相似律高超音速流动驻点温度壁温相似性法则可压缩流动表面温度爆炸波

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高温高超音速流动中的边界层排移和前缘纯度效应

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力学季刊 1966年第2期 63-76页

作者：郑显基 J.GordonHall T.C.golian A.Hertzberg 高流北

绕经细长体或薄体的高超音速流动的两个重要特点是边界层的排移效应和前缘钝度对下游的重大影响.本文对此问题给出了新的理论和实验结果.研究这两个效应的相互作用是将基本的激波层概念加以推广而来进行理论上的处理的.在外部非粘性流动... 详细信息

绕经细长体或薄体的高超音速流动的两个重要特点是边界层的排移效应和前缘钝度对下游的重大影响.本文对此问题给出了新的理论和实验结果.研究这两个效应的相互作用是将基本的激波层概念加以推广而来进行理论上的处理的.在外部非粘性流动中,引进一个包含脱体激波层和熵层的模型以估计钝度影响.在边界层中,求出一个符合局部平板相似的近似解.在弓形激波很强和此热比接近于1的假设下,发展了对于任意薄体的理论.对于平板后身,本理论在一种极限情况得到与爆炸波理论一致的

关键词：高超音速流动可压缩流动方程流体层激波层边界层

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