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Effects of site productivity on individual tree maximum basal area growth rates of Eucalyptus pilularis in subtropical Australia
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作者 P.W.West 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1659-1668,共10页
Inventory data were available from 96 plots of even-aged,monoculture,tall-open forests of Eucalyptus pilularis Smith,aged 2-63 years,growing in sub-tropical regions along the east coast of Australia.A model was develo... Inventory data were available from 96 plots of even-aged,monoculture,tall-open forests of Eucalyptus pilularis Smith,aged 2-63 years,growing in sub-tropical regions along the east coast of Australia.A model was developed relating the maximum possible stem basal area growth rate of individual trees to their stem basal area.For any tree size,this maximum increased as site productivity increased.However,the size at which this maximum occurred decreased as productivity increased.Much research has shown that,at any stand age,trees of a particular stem basal area are taller on more productive sites than on less productive ones.Taller trees incur greater respiratory costs to ensure maintenance of the photo synthetic capacity of their canopies;this reduces their growth rates.It was concluded that trees with larger basal areas will have the maximum possible growth rate on a less productive site,whilst trees with smaller basal areas will have the maximum possible on a more productive site.The model developed may constitute the first stage of a complete individual tree growth model system to predict wood yields from these forests. 展开更多
关键词 Growth model Individual tree Maximum growth rate Eucalyptus pilularis Physiological eff ects
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Effect size in papers published by the Journal of Forestry Research:A missing treasure?
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作者 Evgenios Agathokleous Lei Yu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第2期297-299,共3页
P values based on standard hypothesis testing are commonly reported in articles published by the Journal of Forestry Research(JFR).However,effect sizes are barely used and reported,even if they are of direct relevance... P values based on standard hypothesis testing are commonly reported in articles published by the Journal of Forestry Research(JFR).However,effect sizes are barely used and reported,even if they are of direct relevance to the primary questions of many of the published studies.The incorporation of effect sizes in studies published by JFR should be encouraged and promoted.Inclusion of effect sizes as a requirement in the journal guidelines will facilitate a major change in the way data are tested and interpreted,with the ultimate goal to exempt researchers from the custom of drawing conclusions merely based upon a dichotomous statistical result(P value).Such a policy can also lead to more informed decisions of whether identified effects are of practical relevance to the forestry. 展开更多
关键词 Eff ect magnitude Null hypothesis signifi cance testing P value Science communication Scientifi c writing
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The Influence of Time Scale on the Quantitative Study of Soil and Water Conservation Effect of Grassland
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作者 Xiaoxia WU Zhujun GU 《Asian Agricultural Research》 2015年第4期69-74,共6页
Quantitative analysis of time scale effects is conducive to further understanding of vegetation water and soil conservation mechanism.Based on the observation data of the grass covered and bare soil( control) experime... Quantitative analysis of time scale effects is conducive to further understanding of vegetation water and soil conservation mechanism.Based on the observation data of the grass covered and bare soil( control) experimental plots located in Hetian Town,Changting County of Fujian Province from 2007 to 2010,the characteristics of 4 parameters( precipitation,vegetation,RE and SE) were analyzed at precipitation event,month,season,and annual scales,and then the linear regression models were established to describe the relationships between RE( SE)and its influencing factors of precipitation and vegetation. RE( SE) means the ratio of runoff depth( soil loss) of grass covered plot to that of the control plot. Results show that these 4 parameters presented different magnitude and variation on different time scales. RE and SE were relatively stable either within or among different time scales due to their ratios reducing the influence of other factors. The coupling of precipitation and vegetation led to better water conservation effect at lower RE( < 0. 3) at precipitation event scale as well as at season scale,while the water conservation effect was dominated by precipitation at slightly higher( 0. 3- 0. 4) and higher( > 0. 7) REs at precipitation event scale as well as at annual scale( R2> 0. 78). For the soil conservation effect,precipitation or / and vegetation was / were the dominated influence factor( s) at precipitation event and annual scales,and the grass LAI could basically describe the positive conservation effect( SE <1,R2> 0. 55),while the maximum 30 min intensity( I30) could describe the negative conservation effect more accurately( SE >1,R2> 0. 79). More uncertainties( R2≈0. 4) exist in the models of both RE and SE at two moderate time scales( month and season). Consequently,factors influencing water and soil conservation effect of grass present different variation and coupling characteristics on different time scales,indicating the importance of time scale at the study on water and soil conservation. 展开更多
关键词 Time SCALE LEAF area INDEX Water CONSERVATION effe
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The Non-point Source Pollution Effects of Pesticides Based on the Survey of 340 Farmers in Chongqing City
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作者 Lianchao YU Limeng GU Qian BI 《Asian Agricultural Research》 2015年第7期60-63 67,67,共5页
Using the survey data on 340 farmers in Chongqing City,this paper performs an empirical analysis of the factors influencing the non-point source pollution of pesticides. The results show that the older householders wi... Using the survey data on 340 farmers in Chongqing City,this paper performs an empirical analysis of the factors influencing the non-point source pollution of pesticides. The results show that the older householders will apply more pesticides,which may be due to the weak physical strength and weak ability to accept the concept of advanced cultivation; the householders with high level of education will choose to use less pesticides; the pesticide application rate is negatively correlated with whether farmers have participated in agricultural technology training,that is,the farmers having participated in agricultural technology training have stronger ability to scientifically apply pesticides,and in-depth understanding of advanced agricultural production technology and positive and negative effects of pesticides,so they often choose to reduce the application rate of pesticide; the cognitive factor on the role of pesticides in better promoting the growth of crops is significant,which requires the government and relevant departments to carry out concrete publicity of effectiveness and negative impact of different pesticides during the popularization of agricultural science knowledge,to prompt farmers to have a systematic and in-depth understanding of the agricultural nonpoint source pollution caused by pesticides. 展开更多
关键词 FARMERS PESTICIDES Non-point SOURCE POLLUTION effe
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Therapeutic effect and mechanism of breviscapine on cisplatin-induced nephrotoxicity in mice 被引量:6
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作者 Xiao-Yu Lou Jing-Liang Cheng Bo Zhang 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第10期853-857,共5页
Objective:To observe the protective effect of breviscapineon mice with cisplatin-induced nephrotoxicity.Methods:Mice were given a single injection of cisplalin(8 mg/kg,up.);then,breviscapine was given to mice at 25 mg... Objective:To observe the protective effect of breviscapineon mice with cisplatin-induced nephrotoxicity.Methods:Mice were given a single injection of cisplalin(8 mg/kg,up.);then,breviscapine was given to mice at 25 mg/kg and 50 mg/kg doses,respectively,once a day for seven days.Renal tissue structure was observed after animals were sacrificed.Blood urea nitrogen(BUN),serum creatinine(Scr),lipid peroxide(MDA) and superoxide dismutase(SOD) serum levels were detected;and MDA,glutathione peroxidase,and SOD levels in the renal cortex were detected.Results:Compared with the blank control group(BCG),the kidney pathological damage of mice in the model control group(MCG) was more severe.After applying different doses of breviscapine,different degrees of renal injury improvement appeared.Compared with the BCG,the serum levels of Scr and BUN in the MCG increased to(89.92±6.78) μmoL/L and(15.32±4.53) mmoL/L.The differences were statistical significant(P<0.01).Compared with the MCG,the serum levels of Scr and BUN in the Bre low-dose groups and Bre high-dose groups decreased significantly(P<0.05).Compared with the BCG,the MDA levels in serum and in the renal cortex in the MCG significantly increased,while the SOD levels significantly decreased.Both the differences were statistically significant(P<0.01).In the Bre low-dose groups and Bre high-dose groups,MDA levels in serum and in the renal cortex significantly decreased,while SOD and glutathione peroxidase levels in the renal cortex significantly increased,compared with the MCG;and the differences were statistically significant(P<0.05).Conclusions:Breviscapine can reduce cisplatin induced renal toxicity in mice and it's possible through inhibition of renal tubule cell lipid peroxidation and reduces the nephrotoxicity of cisplatin. 展开更多
关键词 CISPLATIN RENAL INJURY BREVISCAPINE Protective eff
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The plurality effect of topographical irregularities on site seismic response 被引量:6
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作者 Saeed Ghaffarpour Jahromi Sama Karkhaneh 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第3期521-534,共14页
Topography can have signifi cant eff ects on seismic ground response during an earthquake because topographic irregularities cause considerable diff erences between the seismic waves emitted by the source and the wave... Topography can have signifi cant eff ects on seismic ground response during an earthquake because topographic irregularities cause considerable diff erences between the seismic waves emitted by the source and the waves reaching the ground surface. When a seismic motion happens in a topographically irregular area, seismic waves are trapped and refl ected between the topographic features. Therefore, the interaction between topographies can amplify seismic ground response. In order to reveal how interaction between topographies infl uences seismic response, several numerical fi nite element studies have been performed by using the ABAQUS program. The results show that topographic features a greater distance between the seismic source and the site would cause greater seismic motion amplifi cation and is perceptible for the hills far away from the source and the ridges. Also, site acceleration response is impacted by surrounding topography further than site velocity and displacement response. 展开更多
关键词 TOPOGRAPHY eff ECTS surrounding TOPOGRAPHY site seismic response ABAQUS PROGRAM and PLAXIS PROGRAM
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Effect of site amplification on inelastic seismic response 被引量:4
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作者 Adhikary S Singh Y 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第3期535-554,共20页
The available models for eff ective periods of site and structure are reviewed in context of frequency tuning in the inelastic seismic response of soil-structure system. The eff ect of seismic intensity and ductility ... The available models for eff ective periods of site and structure are reviewed in context of frequency tuning in the inelastic seismic response of soil-structure system. The eff ect of seismic intensity and ductility demand, on the eff ective periods, is investigated, and inelastic site amplifi cation is shown to be strongly correlated to the normalized eff ective period. Two non-dimensional parameters, analogous to the conventional site amplifi cation factors in codes, are defi ned to quantify the inelastic site amplifi cation. It is shown that the inelastic site amplifi cation factor (i.e. ratio of constant ductility spectral ordinates at soil site to those at rock outcrop) is able to represent the site eff ects more clearly, as compared to the inelastic site amplifi cation ratio (i.e. ratio of inelastic spectral ordinates at soil site to the corresponding elastic spectral ordinates at rock outcrop). Further, the peak in the amplifi cation factor corresponding to the eff ective site period diminishes rapidly with increasing ductility demand. 展开更多
关键词 SITE amplifi CATION normalized RESPONSE SPECTRA eff ective period INELASTIC SEISMIC RESPONSE INELASTIC SITE amplifi CATION factor
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Sliding speed calculation of the Wenchuan earthquake fault using the Doppler effect
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作者 Li Qi-Cheng He Shu-Geng Min Ye 《Applied Geophysics》 SCIE CSCD 2021年第2期264-271,274,共9页
Currently,the fault sliding speed functions or source–time functions used in theoretical seismogram calculations have only produced theoretical results;that is,the results of the fault speed–time functions have been... Currently,the fault sliding speed functions or source–time functions used in theoretical seismogram calculations have only produced theoretical results;that is,the results of the fault speed–time functions have been obtained only from theoretical studies,and have not been validated using the measured data.This paper signifi cantly improves the method for calculating fault sliding speed using the Doppler eff ect,from the following four perspectives.First,the paper theoretically demonstrates how to confirm that the seismic waves received in some frequency bands by two diff erent receivers are emitted by the same source.Second,the paper proposes a method to determine the similarity of seismic waves received by two diff erent receivers in some frequency bands;it applies the relative change at the two receivers in Fourier amplitude standard deviation in some frequency bands,and determines that similar seismic waves are emitted by the same frequency bands.Third,to eliminate the interference of reflected and refracted waves,this study uses fault sliding time S-wave records for data processing.Finally,the paper replaces the long-time Fourier transform with short-time Fourier transform to enhance the positioning accuracy of fault sliding times.Based on these perspectives,the paper systematically summarizes a general methodology for calculating the fault sliding speed using the Doppler effect.This method is employed to calculate the fault sliding speed of the Wenchuan earthquake;the calculations reveal that there is a general correlation between the fault sliding speeds of the Wenchuan earthquake and the seismic moment changes.The results confi rm that the sliding speed of the Wenchuan earthquake fault possesses the characteristics of abrupt change,whereby a sudden increase in the sliding speed is followed by a rapid decrease.Generally,the sliding speed is not fast,and sometimes,no sliding occurs.There are obvious diff erences from the currently used sliding speed functions,such as the Haskell function,bell-shaped function,exponential function,and triangular function.To determine the fault sliding speed using the Doppler eff ect,only the earthquake records and locations of the epicenter and receivers are required,instead of using unknown crust parameters.In short,the proposed calculation method has clear physical meaning,and the required parameters are easier to obtain. 展开更多
关键词 Doppler eff ect sliding speed FAULT EARTHQUAKE
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Metabolomics Combined with Network Pharmacology Uncovers Effective Targets of Tao-Hong-Si-Wu Decoction for Its Protection from Sepsis-Associated Acute Lung Injury 被引量:1
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作者 Jinzhi He Longfei Wang +3 位作者 Yang Wang Zeng Li Feihu Chen Zhicheng Liu 《Journal of Analysis and Testing》 EI CSCD 2023年第2期172-186,共15页
Sepsis-induced acute lung injury(ALI)is a leading cause of death among septic complications.Tao-Hong-Si-Wu decoction(TSD),a classical recipe from traditional Chinese medicine used for treating ischemic stroke,has been... Sepsis-induced acute lung injury(ALI)is a leading cause of death among septic complications.Tao-Hong-Si-Wu decoction(TSD),a classical recipe from traditional Chinese medicine used for treating ischemic stroke,has been recently reported to alleviate inflammation and inflammation-stimulated injuries related to the pathology of ALI.Here,we first observed the therapeutic effect of TSD on sepsis-induced ALI.Based on integrated metabolomics and network pharmacology analysis(NPA)techniques,we aim to understand the mechanism of TSD alleviating ALI.TSD’s effects were observed in rats modeled by cecal ligation and puncture(CLP)and rat macrophages stimulated by lipopolysaccharide(LPS).Metabolomics analyses were applied to determine the ingredients in the medicine and key metabolites correlated to the NPA for the prediction of TSD targets.Gene and protein expressions of the key predicted targets were evaluated in the lung tissue and macrophages of septic model rat by quantitative polymerase chain reaction(PCR)and enzyme-linked immunosorbent assays,respectively.TSD improved survival rate and protected against lung injury in CLP rats.Eleven endogenous metabolites were related to TSD’s actions.TSD significantly suppressed IL-6 and TNF-αsecretions and their gene expressions both in the lung tissue of the model rats and in LPS-stimulated macrophages.TSD also restored decreased lung protein expression of VEGFA in septic model rats.Targeted proteins and their affecting metabolites were finally validated in an external test set of rats.This study shows that metabolomics coupled with NPA is a promising approach to explore potential targets of medicine with complex compositions. 展开更多
关键词 Metabolomics Drug eff ect analysis SEPSIS Traditional Chinese medicine CYTOKINES BIOANALYSIS
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基于优化极限学习机模型的反应堆中子通量与k_(eff)预测方法研究
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作者 陈镜宇 刘喜洋 +2 位作者 赵鹏程 刘紫静 李卫 《核技术》 EI CAS CSCD 北大核心 2024年第10期178-187,共10页
通过模拟和扩展人类智能,人工智能能够解决预测反应堆k_(eff)和中子通量等问题。本研究选用国际原子能机构(International Atomic Energy Agency,IAEA)反应堆作为研究对象,以稳态时的堆芯中子通量和k_(eff)为预测量,通过堆芯物理分析程... 通过模拟和扩展人类智能,人工智能能够解决预测反应堆k_(eff)和中子通量等问题。本研究选用国际原子能机构(International Atomic Energy Agency,IAEA)反应堆作为研究对象,以稳态时的堆芯中子通量和k_(eff)为预测量,通过堆芯物理分析程序ADPRES生成数据样本后,利用极限学习机(Extreme Learning Machine,ELM)构建中子通量和k_(eff)的基础神经网络模型,随后通过随机森林(Random Forest,RF)评估特征值重要程度以建立各模型最佳输入特征子集,采用遍历方法确定隐藏层最佳神经元数目,最后使用鲸鱼优化算法(Whale Optimization Algorithm,WOA)对其初始权值与阈值进行优化,进一步提高了模型的精度。研究结果显示:经降维优化处理后,神经网络的预测能力有较大提升,其中k_(eff)的预测精度提高了两个量级,中子通量的预测误差降低了87.24%,并且减少了模型训练时间。本文构建方法对快速评估堆芯物理特性有一定参考意义。 展开更多
关键词 极限学习机 鲸鱼优化算法 中子通量 k_(eff) 参数预测方法 随机森林
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基于AL-Kriging模型及PSO算法的桥机主梁优化
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作者 肖辉 范小宁 《机械研究与应用》 2024年第2期52-55,共4页
为解决有限元模型和群智能算法相结合的起重机结构优化计算的计算成本昂贵的问题,该文基于AL-Kriging代理模型和粒子群智能优化算法构建了起重机主梁优化方法,在该方法中通过EFF学习函数选择优化所需的有效样本点,从而用较少的高保真计... 为解决有限元模型和群智能算法相结合的起重机结构优化计算的计算成本昂贵的问题,该文基于AL-Kriging代理模型和粒子群智能优化算法构建了起重机主梁优化方法,在该方法中通过EFF学习函数选择优化所需的有效样本点,从而用较少的高保真计算样本构建出满足精度要求的代理模型,再通过PSO算法以及所构建好的代理模型完成结构优化。通过工程案例验证证明,在取得同样计算结果的情况下,与基于静态Kriging模型相比,该方法的优化时间节省了70%,调用样本数仅为静态代理模型的27%,证明了所构建的优化方法是可行和有效的。 展开更多
关键词 起重机主梁 Kriging代理模型 EFF学习函数 智能优化
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Boosted Electrocatalytic Glucose Oxidation Reaction on Noble-Metal-Free MoO_(3)-Decorated Carbon Nanotubes
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作者 Yu-Long Men Ning Dou +3 位作者 Yiyi Zhao Yan Huang Lei Zhang Peng Liu 《Transactions of Tianjin University》 EI CAS 2024年第1期63-73,共11页
Electrocatalytic glucose oxidation reaction(GOR)has attracted much attention owing to its crucial role in biofuel cell fabrication.Herein,we load MoO_(3)nanoparticles on carbon nanotubes(CNTs)and use a discharge proce... Electrocatalytic glucose oxidation reaction(GOR)has attracted much attention owing to its crucial role in biofuel cell fabrication.Herein,we load MoO_(3)nanoparticles on carbon nanotubes(CNTs)and use a discharge process to prepare a noblemetal-free MC-60 catalyst containing MoO_(3),Mo_(2)C,and a Mo_(2)C–MoO_(3)interface.In the GOR,MC-60 shows activity as high as 745μA/(mmol/L cm^(2)),considerably higher than those of the Pt/CNT(270μA/(mmol/L cm^(2)))and Au/CNT catalysts(110μA/(mmol/L cm^(2))).In the GOR,the response minimum on MC-60 is as low as 8μmol/L,with a steady-state response time of only 3 s.Moreover,MC-60 has superior stability and anti-interference ability to impurities in the GOR.The better performance of MC-60 in the GOR is attributed to the abundant Mo sites bonding to C and O atoms at the MoO_(3)–Mo_(2)C interface.These Mo sites create active sites for promoting glucose adsorption and oxidation,enhancing MC-60 performance in the GOR.Thus,these results help to fabricate more effi cient noble-metal-free catalysts for the fabrication of glucose-based biofuel cells. 展开更多
关键词 Interface eff ect ELECTROCATALYSIS Molybdenum oxide GLUCOSE Oxidation reaction
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Method of fabricating artificial rock specimens based on extrusion free forming(EFF)3D printing
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作者 Xiaomeng Shi Tingbang Deng +2 位作者 Sen Lin Chunjiang Zou Baoguo Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1455-1466,共12页
Three-dimensional(3D)printing technology has been widely used to create artificial rock samples in rock mechanics.While 3D printing can create complex fractures,the material still lacks sufficient similarity to natura... Three-dimensional(3D)printing technology has been widely used to create artificial rock samples in rock mechanics.While 3D printing can create complex fractures,the material still lacks sufficient similarity to natural rock.Extrusion free forming(EFF)is a 3D printing technique that uses clay as the printing material and cures the specimens through high-temperature sintering.In this study,we attempted to use the EFF technology to fabricate artificial rock specimens.The results show the physico-mechanical properties of the specimens are significantly affected by the sintering temperature,while the nozzle diameter and layer thickness also have a certain impact.The specimens are primarily composed of SiO_(2),with mineral compositions similar to that of natural rocks.The density,uniaxial compressive strength(UCS),elastic modulus,and tensile strength of the printed specimens fall in the range of 1.65–2.54 g/cm3,16.46–50.49 MPa,2.17–13.35 GPa,and 0.82–17.18 MPa,respectively.It is capable of simulating different types of rocks,especially mudstone,sandstone,limestone,and gneiss.However,the simulation of hard rocks with UCS exceeding 50 MPa still requires validation. 展开更多
关键词 Artificial rock 3D printing Extrusion free forming(EFF) Similarity analysis Mechanical properties
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Bauschinger-Like Effect of AZ31 Magnesium Alloy Wide Sheet During the Straightening Process 被引量:2
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作者 Fangkun Ning Qichi Le +1 位作者 Yonghui Jia Liang Chen 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2021年第9期1255-1264,共10页
The Bauschinger-like effect, which showed up in the straightening process of the AZ31 magnesium alloy wide sheet, was investigated through the multi-pass discrete three-point bending–unloading–bending(BUB) experimen... The Bauschinger-like effect, which showed up in the straightening process of the AZ31 magnesium alloy wide sheet, was investigated through the multi-pass discrete three-point bending–unloading–bending(BUB) experiments. The stress variable, anisotropy, and asymmetry of tension and compression on the straightening process were corresponding to the Bauschingerlike effect. The Bauschinger-like effect in the initial, intermediate, and end of the straightening process was dominated by the twinning, detwinning, and dislocation induced by pyramidal < c + a > slip, respectively. Also, they were responsible for the transformation of the Bauschinger stress parameter(BSP) and Bauschinger energy parameter(BEP). Later, the anisotropic nonlinear kinematic hardening model(ANK model) to describe the Bauschinger-like effect was optimized and simplified. 展开更多
关键词 Bauschinger-like eff ect STRAIGHTENING Discrete experiments Anisotropic nonlinear kinematic hardening model(ANK model)
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蒙古马胎儿成纤维细胞永生化细胞体系建立的研究
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作者 田书岳 神英超 +7 位作者 王希生 王敏 伊敏娜 才文道力玛 陶力 赵毕力格 芒来 格日乐其木格 《中国畜牧兽医》 CAS CSCD 北大核心 2023年第1期46-57,共12页
【目的】试验旨在建立永生化蒙古马胎儿成纤维细胞(equine fetal fibroblasts,EFFs)系,为马繁殖与发育生物学研究提供参考。【方法】采用1 mg/mL胶原酶Ⅳ消化分离原代EFFs,利用表达人端粒酶逆转录亚基(hTERT)和潮霉素B抗性的pLV-hTERT-I... 【目的】试验旨在建立永生化蒙古马胎儿成纤维细胞(equine fetal fibroblasts,EFFs)系,为马繁殖与发育生物学研究提供参考。【方法】采用1 mg/mL胶原酶Ⅳ消化分离原代EFFs,利用表达人端粒酶逆转录亚基(hTERT)和潮霉素B抗性的pLV-hTERT-IRES-hygro慢病毒感染EFFs,经潮霉素B筛选得到阳性细胞hTERT-EFFs,以第3代EFFs为对照,采用实时荧光定量PCR检测hTERT mRNA的表达水平,CCK-8法绘制生长曲线检测细胞增殖能力,流式细胞仪检测细胞凋亡情况,β-半乳糖苷酶染色检测细胞衰老情况。使用DNAMAN软件比对分析人、马、小鼠、牛、绵羊、猪多物种TERT核苷酸、蛋白和端粒酶RNA组分(TERC)序列相似性。【结果】原代EFFs在实验室培养体系下可传至17代,但第17代细胞发生了衰老。hTERT基因可成功转入EFFs,并至少稳定表达20代。然而hTERT-EFFs增殖能力显著低于EFFs(P<0.05),hTERT-EFFs凋亡早期细胞率显著高于EFFs(P<0.05)。细胞衰老检测结果表明,hTERT-EFFsβ-半乳糖苷酶染色呈阳性。序列相似性比对结果显示,马TERT与hTERT mRNA保守性较高,相似性为73.2%;马TERT与hTERT蛋白保守性较其他物种高,相似性为76.3%,表明马TERT与hTERT在结构和功能上是高度相似;马TERC与人TERC相似性较高,在进化树上位于同一分支,但马TERC与TERT的结合及与端粒酶活性相关的关键核苷酸中存在突变。【结论】单独过表达hTERT可以延长EFFs体外传代次数不超过30代,但仍不足以使蒙古马EFFs细胞高质量永生化,这可能与hTERT与eTERC不相容有关。 展开更多
关键词 蒙古马 马胎儿成纤维细胞(EFFs) 永生化 人端粒酶逆转录亚基(hTERT) 细胞增殖
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基于主动学习的Kriging模型的可靠性分析 被引量:1
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作者 翟玮昊 龚敏浩 +2 位作者 林名润 匡婷玉 文珊珊 《空天防御》 2023年第1期1-5,共5页
航天工程中结构可靠性要求较高,失效概率小,利用传统Monte Carlo法得到精确解需要极大的计算量。针对此问题,提出将拉丁超立方抽样与Kriging代理模型结合,建立初始的Kriging代理模型,利用预期可行性函数(expected feasibility function,... 航天工程中结构可靠性要求较高,失效概率小,利用传统Monte Carlo法得到精确解需要极大的计算量。针对此问题,提出将拉丁超立方抽样与Kriging代理模型结合,建立初始的Kriging代理模型,利用预期可行性函数(expected feasibility function,EFF)学习机制对已建立的初始模型进行主动学习,得到拟合误差最小的模型,再利用Monte Carlo法进行可靠性计算,极大地降低了计算量。最后,通过三个数值算例验证了本文方法的精度和效率。 展开更多
关键词 可靠性 拉丁超立方抽样 Kriging代理模型 EFF学习机制
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Testing phaeophytinization as an index of ozone stress in trees
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作者 Evgenios Agathokleous Mitsutoshi Kitao Takayoshi Koike 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第4期1167-1174,共8页
Ground-level ozone pollution is a menace for vegetation in the northern hemisphere,limiting photosynthetic pigments and suppressing photosynthesis in trees and other types of plants.Phaeophytinization is the process o... Ground-level ozone pollution is a menace for vegetation in the northern hemisphere,limiting photosynthetic pigments and suppressing photosynthesis in trees and other types of plants.Phaeophytinization is the process of converting chlorophylls into phaeophytins,for example by acidifi cation.Ozone is a highly oxidizing molecule and well known to degrade chlorophylls;however,the eff ect of ozone on phaeophytinization in leaves of higher plants is largely unknown.To reveal ozone eff ect on phaeophytinization and evaluate the potential of phaeophytinization as an index of ozone stress in trees,the absorbance at the optical density of 665 nm was measured before(OD_(665))and after(OD_(665a))acidifi cation in three independent experiments with nearly 30 conditions of ozone exposure.Both current ambient and elevated ozone widely aff ected phaeophytinization,as indicated by decreases or increases in the phaeophytinization quotient OD_(665)/OD_(665a).These eff ects were commonly moderate to large in magnitude and practically signifi cant,and occurred even in ozone-asymptomatic leaves.It emerges that the ozone eff ect on phaeophytinization is bimodal,likely depending on the intensity of ozone stress.These results indicate a promising feature of OD_(665)/OD_(665a)as a thorough index of ozone stress in the future,but further studies are needed to reveal the underlying biochemical mechanisms of the bimodal eff ect on phaeophytinization. 展开更多
关键词 Biological stress Chemical eff ect Chlorophyll oxidation Environmental stimuli Phaeophytin
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Single and combined eff ects of fertilization,ectomycorrhizal inoculation,and drought on container-grown Japanese larch seedlings
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作者 Evgenios Agathokleous Mitsutoshi Kitao +3 位作者 Masabumi Komatsu Yutaka Tamai Hisanori Harayama Takayoshi Koike 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第4期1077-1094,共18页
Climate change can intensify drought in many regions of the world and lead to more frequent drought events or altered cycles of soil water status.Therefore,it is important to enhance the tolerance to drought and thus ... Climate change can intensify drought in many regions of the world and lead to more frequent drought events or altered cycles of soil water status.Therefore,it is important to enhance the tolerance to drought and thus health,vigor,and success of transplantation seedlings used in the forestry by modifying fertilization and promoting mycorrhization.Here,we sowed seeds of Japanese larch(Larix kaempferi)in 0.2-L containers with 0.5 g(low fertilization;LF)or 2 g(high fertilization;HF)of slow-release fertilizer early in the growing season.One month later,we irrigated seedlings with non-sterilized ectomycorrhizal inoculum(ECM)or sterilized solution(non-ECM),and after about 2 months,plants were either kept well watered(WW;500 mL water/plant/week)or subjected to drought(DR;50 mL water per plant/week)until the end of the growing season.HF largely stimulated plant growth and above-and belowground biomass production,eff ects that are of practical signifi cance,but caused a small decrease in stomatal conductance(Gs 390)and transpiration rate(E 390),which in practice is insignifi cant.ECM treatment resulted in moderate inhibition of seedling growth and biomass and largely canceled out the enhancement of biomass and foliar K content by HF.DR caused a large decrease in CO 2 assimilation,and enhanced stomatal closure and induced senescence.DR also largely depleted foliar Mg and enriched foliar K.Although DR caused a large decrease in foliar P content in LF,it moderately increased P in HF.Likewise,DR increased foliar K in HF but not in LF,and decreased foliar P in ECM plants but not in non-ECM plants.Conversely,ECM plants exhibited a large enrichment in foliar P under WW and had a lower water potential under DR when grown in LF.These results indicate that the drought tolerance and health and vigor of Japanese larch seedlings can be modifi ed by soil fertility and soil microorganisms.This study provides a basis for new multifactorial research programs aimed at producing seedlings of superior quality for forestation under climate change. 展开更多
关键词 DROUGHT ECTOMYCORRHIZAE Fertilizer eff ect Oxidative stress Stressor interactions
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An empirical analysis of comprehensive benefits of waste power generation
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作者 YANG Yu-wen ZHANG Si-jia 《Ecological Economy》 2015年第3期223-229,共7页
With the rapid development of economy, the scale of city has become more and more large. Meanwhile, the population also grows rapidly. Although the standard of living condition has been improved greatly, industry and ... With the rapid development of economy, the scale of city has become more and more large. Meanwhile, the population also grows rapidly. Although the standard of living condition has been improved greatly, industry and domestic waste not only infl uence the quality of life by polluting the environment, but also become a signifi cant obstacle factor for economic development. waste power generation or waste-to-energy(WTE) is using the heat which is from garbage incinerator to generate electricity. This method can solve the problem of waste and generate the social benefi t, but by using the power on the internet to generate the economy benefit. In this paper, combined the method of FAHP and TOPSIS, a quotas system is set up to evaluate the social and economic benefi ts of the WTE project in Xiamen. Some advice is proposed for the Xiamen WTE project. 展开更多
关键词 WASTE POWER GENERATION SOCIAL effect ECONOMIC effe
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中国IPO定价效率研究——基于IPO抑价率和EFF值的比较分析 被引量:13
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作者 陈训波 贺炎林 《经济理论与经济管理》 CSSCI 北大核心 2013年第8期47-59,共13页
IPO定价效率是IPO市场的一个研究热点。本文以沪深A股市场首次公开发行并上市的新股为样本,通过IPO抑价率和EFF值指标比较分析了IPO定价效率的行业特征和定价制度特征。研究表明:EFF均值在行业之间的差异不显著,而IR均值在行业之间差异... IPO定价效率是IPO市场的一个研究热点。本文以沪深A股市场首次公开发行并上市的新股为样本,通过IPO抑价率和EFF值指标比较分析了IPO定价效率的行业特征和定价制度特征。研究表明:EFF均值在行业之间的差异不显著,而IR均值在行业之间差异显著;我国IPO定价效率未随时间推移而不断提高,EFF值和IR值呈现出无趋势的特征。在此基础上,本文认为我国IPO定价效率不高的主要原因不是一级市场低价发行,而是二级市场投资者的追捧和半市场化性质的改革,提高IPO定价效率的根本途径在于回归市场化改革。 展开更多
关键词 IPO抑价率 EFF值 行业特征 IPO定价效率
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