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基于SVAR模型的期锌市场及其现货市场的价格发现功能实证研究 被引量:6
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作者 贺正楚 周贤军 文先明 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2011年第7期87-92,共6页
立足于期货市场的基本功能,利用SVAR模型发现期锌市场及其现货市场对来自各自身的冲击反应迅速,且具有强持续性;期货市场对现货市场冲击是积极、有效的,但现货市场对期货的冲击是消极、微弱的.方差分解表明期锌市场94%比例来自于自身,6... 立足于期货市场的基本功能,利用SVAR模型发现期锌市场及其现货市场对来自各自身的冲击反应迅速,且具有强持续性;期货市场对现货市场冲击是积极、有效的,但现货市场对期货的冲击是消极、微弱的.方差分解表明期锌市场94%比例来自于自身,6%来自现货市场.而现货市场在达到稳定状态后只有10%来自于自身,90%来自于期货市场.研究结果为套期保值时点的选择提供了重要的理论参考依据. 展开更多
关键词 功能 期锌 市场 价格发现 SVAR模型
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非线性、分形与期锌市场价格 被引量:1
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作者 文先明 周贤军 张蜜 《财经理论与实践》 CSSCI 北大核心 2011年第3期31-35,共5页
从非线性角度研究期锌市场,运用R/S分析法对期锌市场进行分析,发现期锌市场的Hurst指数为0.6183,其价格收益率序列是分维时间序列,具有分形结构,维数为1.6174。期锌市场的平均周期长度为176天,具有强持续性和相关性。关联系数为19.47%,... 从非线性角度研究期锌市场,运用R/S分析法对期锌市场进行分析,发现期锌市场的Hurst指数为0.6183,其价格收益率序列是分维时间序列,具有分形结构,维数为1.6174。期锌市场的平均周期长度为176天,具有强持续性和相关性。关联系数为19.47%,远远大于国外相关市场。在风险方面,期锌市场的风险比期铜市场的要小,而比股票市场的风险要大。 展开更多
关键词 非线性 分形 HURST指数 关联系数 期锌市场
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云南云县邦挖河铅锌矿成因
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作者 郭桂林 吴道鹏 梅朴莲 《云南地质》 2009年第4期388-391,共4页
铅锌矿赋存于澜沧群下亚群(Pz1ln1),晚期花岗岩浆含矿热液沿围岩层间及矿体裂隙中沉淀结晶形成含方铅矿的方解石脉和石英脉,矿床成因属期后热液脉状矿。
关键词 后热液铅 构造控矿 印支花岗岩 澜沧群受矿 云南云县邦挖河
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Effect of MnO_4^- and silver content on electrochemical behaviour of Pb-Ag alloy anodes during potential decay periods 被引量:4
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作者 张伟 涂常青 +2 位作者 陈艺锋 Houlachi GEORGEOS 肖利 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2174-2180,共7页
The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay ... The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay periods. When the anodes were immersed into acid zinc sulphate electrolyte without MnO4- ions, the Pb-0.72%Ag anode entered complete passivation state in the shortest time among the five anodes, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by measurement of open circuit potential. During immersion of the anodes, MnO4 ions accelerated the passivation and increased the corrosion current density of the anodes. After immersion in zinc electrolyte with MnO4-, the anode Pb-0.72%Ag had the best corrosion resistance, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, then the close anodes Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by the electrochemical impedance spectroscopy (EIS) analysis. 展开更多
关键词 electrochemical behaviour Pb-Ag anode permanganate ion potential decay periods zinc sulphate electrolyte
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Metabolically based liver damage pathophysiology in patients with urea cycle disorders-A new hypothesis 被引量:4
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作者 Ivan Ivanovski Milos Jesic +2 位作者 Ana Ivanovski Livia Garavelli Petar Ivanovski 《World Journal of Gastroenterology》 SCIE CAS 2017年第44期7930-7938,共9页
The underlying pathophysiology of liver dysfunction in urea cycle disorders(UCDs) is still largely elusive. There is some evidence that the accumulation of urea cycle(UC) intermediates are toxic for hepatocyte mitocho... The underlying pathophysiology of liver dysfunction in urea cycle disorders(UCDs) is still largely elusive. There is some evidence that the accumulation of urea cycle(UC) intermediates are toxic for hepatocyte mitochondria. It is possible that liver injury is directly caused by the toxicity of ammonia. The rarity of UCDs, the lack of checking of iron level in these patients, superficial knowledge of UC and an underestimation of the metabolic role of fumaric acid, are the main reasons that are responsible for the incomprehension of the mechanism of liver injury in patients suffering from UCDs. Owing to our routine clinical practice to screen for iron overload in severely ill neonates, with the focus on the newborns suffering from acute liver failure, we report a case of citrullinemia with neonatal liver failure and high blood parameters of iron overload. We hypothesize that the key is in the decreased-deficient fumaric acid production in the course of UC in UCDs that causes several sequentially intertwined metabolic disturbances with final result of liver iron overload. The presented hypothesis could be easily tested by examining the patients suffering from UCDs, for liver iron overload. This could be easily performed in countries with a high population and comprehensive national register for inborn errors of metabolism. Conclusion: Providing the hypothesis is correct, neonatal liver damage in patients having UCD can be prevented by the supplementation of pregnant women with fumaric or succinic acid, prepared in the form of iron supplementation pills. After birth, liverdamage in patients having UCDs can be prevented by supplementation of these patients with zinc fumarate or zinc succinylate, as well. 展开更多
关键词 Urea cycle disorder CITRULLINEMIA Neonatal liver iron overload Fumaric acid Succinic acid Krebs' cycle TRANSFERRIN Zinc fumarate supplementation
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A Remark on the Generalized Roper-Suffridge Extension Operator for Spirallike Mappings of Type β and Order α 被引量:21
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作者 LIU Xiao-song FENG Shu-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第2期310-316,共7页
Suppose f is a spirallike function of type β and order α on the unit disk D.Let Ωn,p1,p2,…,pn={z=(z2,z2,…,zn)′∈C^n:∑j=1^n|zj)^Pj〈1},where 1≤p1≤2,pj≥1,j=2,…,n,are real numbers.In this paper,we will pr... Suppose f is a spirallike function of type β and order α on the unit disk D.Let Ωn,p1,p2,…,pn={z=(z2,z2,…,zn)′∈C^n:∑j=1^n|zj)^Pj〈1},where 1≤p1≤2,pj≥1,j=2,…,n,are real numbers.In this paper,we will prove that Φn,β2,γ2,…βn,γn(f)(z)=(f(z1), preserves spirallikeness of type β and order α on Ωn,p1,p2,…,Pn. 展开更多
关键词 K spirallike mapping of type β and order β starlike mapping of order α gener-alized Roper-Suffridge extension operator
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Effect of Metallothionein on Cell Cycle,Apoptosis Rate and Subsets Distribution of Lymphocytes in Peripheral Blood of Dairy Cattle under Heat Stress 被引量:1
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作者 Jiajie LUO Lili LI +7 位作者 Bin ZHANG LiZhuan WU Zijun LI Ying PENG JueXin FAN XinYi LAN JinShun ZHAN Jun FANG 《Agricultural Science & Technology》 CAS 2013年第10期1457-1461,共5页
[Objective] This study aimed to research the effect of metallothionein on cell cycle, apoptosis rate and subsets distribution of lymphocytes in peripheral blood of dairy cows under heat stress, so as to perfect the re... [Objective] This study aimed to research the effect of metallothionein on cell cycle, apoptosis rate and subsets distribution of lymphocytes in peripheral blood of dairy cows under heat stress, so as to perfect the regulative mechanism re- searches of MT to anti-heat stress. [Method] Twenty lactating Chinese Holstein cows were randomly divided into four groups (A, B, C and D), and injected with 0, 4.0, 8.0 and 12.0 mg Zn-metallothionein, respectively by intravenous route. Blood sam- ples were collected at 1", 16~, 31~, 46~ and 61~ day, and the dynamic changes of cell cycle, apoptosis rate and subsets distribution of lymphocytes were determined. [Result] The apoptosis rate of cells in group B and C was lower than those in group A by 26.63% (P〉0.05) and 24.84% (P〉0.05) respectively. The number of cells in the Gc/G1 phage in trial groups was increased and the number of cells in the S and GJM phages tended to decrease, but there were no significant differences (P〉 0.05). The number of CD3~ T cell in three trial groups was greater than those in group A by 7.02% (P〉0.05), 5.45% (P〉0.05) and 3.85% (P〉0.05) respectively, while the number of CD4~ T cell in trial groups was higher than those in control group by 31.04% (P〈0.05), 35.68% (P〈0.05) and 39.34% (P〈0.05) respectively. The number of CD8' T cell and the levels of CD4*/CD8~ in trial groups were increased observ- ably, but significant difference (P〈0.05) was observed in the levels of CD4~/CD8~ between groups A and C only. It demonstrated that exogenous Zn-metallothionein can decrease apoptosis rate, improve cell cycle and regulate subsets distribution of lymphocytes in dairy cattle in a dose-dependent manner. [Conclusion] This study will provide scientific basis for safe utilization of MT in dairy industry. 展开更多
关键词 Exogenous metallothionein Heat stress Immunity Dynamic change Chinese Holstein cows
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On the solutions and periodic nature of some systems of difference equations 被引量:2
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作者 E. M. Elsayed 《International Journal of Biomathematics》 2014年第6期121-146,共26页
In this paper, we consider the solution of the following rational systems of difference equations:xn+1=zn-1xn-2/xn-2±yn,yn+1=xn-1yn-2/yn-2±zn,zn+1=yn-1zn-2/zn-1±xn,where initial conditions are nonze... In this paper, we consider the solution of the following rational systems of difference equations:xn+1=zn-1xn-2/xn-2±yn,yn+1=xn-1yn-2/yn-2±zn,zn+1=yn-1zn-2/zn-1±xn,where initial conditions are nonzero real numbers. 展开更多
关键词 Difference equations recursive sequences periodic solutions system of differ-ence equations stability.
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