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Journal of Central South University 2019年第7期26卷 1706-1718页

作者： zhang jia-hua zhang Biao Work Safety Key Lab on Prevention and Control of Gas and Roof Disasters for Southern Coal Mines Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal Mines Hunan University of Science and Technology Xiangtan 411201 China School of Civil Engineering Hunan University of Science and Technology Xiangtan 411201 China

A new horn failure mechanism was constructed for tunnel faces in the soft rock mass by means of the logarithmic spiral curve. The seismic action was incorporated into the horn failure mechanism using the pseudo-static method. Considering the randomness of rock mass parameters and loads, a three-dimensional (3D) stochastic collapse model was established. Reliability analysis of seismic stability of tunnel faces was presented via the kinematical approach and the response surface method. The results show that, the reliability of tunnel faces is significantly affected by the supporting pressure, geological strength index, uniaxial compressive strength, rock bulk density and seismic forces. It is worth noting that, if the effect of seismic force was not considered, the stability of tunnel faces would be obviously overestimated. However, the correlation between horizontal and vertical seismic forces can be ignored under the condition of low calculation accuracy.

关键词： 3D stochastic collapse model pseudo-static method response surface method reliability index safety factor support pressure

水陆二仙丹联合抵挡汤加减方对早中期糖尿病肾病患者的临床疗效

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中成药 2024年第5期46卷 1514-1519页

作者：郭建恩张佳华张园纪品川高志旭高占华安丽萍杨佳琦常柏天津中医药大学研究生院天津301617 承德医学院河北承德067000 承德市中医院河北承德067000 天津医科大学朱宪彝纪念医院天津300070

目的探讨水陆二仙丹联合抵挡汤加减方对早中期糖尿病肾病患者的临床疗效。方法83例患者随机分为对照组(42例)和观察组(41例),对照组给予厄贝沙坦片,观察组在对照组基础上加用水陆二仙丹联合抵挡汤加减方,疗程12周。检测临床疗效、中医... 详细信息

目的探讨水陆二仙丹联合抵挡汤加减方对早中期糖尿病肾病患者的临床疗效。方法83例患者随机分为对照组(42例)和观察组(41例),对照组给予厄贝沙坦片,观察组在对照组基础上加用水陆二仙丹联合抵挡汤加减方,疗程12周。检测临床疗效、中医证候评分、血糖指标(FBG、HbA1c)、血脂指标(TC、TG)、肾功能指标(BUN、Scr、24 h UTP、eGFR)、炎症因子(IL-1β、hs-CRP、IL-6、TNF-α、IL-18、TGF-β1)、免疫功能指标(淋巴细胞、中性粒细胞、CD8^(+)、CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+))、不良反应发生率变化。结果观察组总有效率高于对照组(P0.05)。结论水陆二仙丹联合抵挡汤加减方可安全有效地改善早中期糖尿病肾病患者临床症状,其机制可能与降低炎症水平、改善机体免疫功能有关。

关键词：水陆二仙丹抵挡汤加减方厄贝沙坦片早中期糖尿病肾病

Equation of State of Protoneutron Star with Trapped Neutrinos

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Communications in Theoretical Physics 2006年第5期45卷 901-905页

作者： zhang hua jia huan-Yu Institute of Morden Physics Southwest Jiaotong University Chengdu 610031 China

The influence of trapped neutrinos on the proto-neutron star is studied in the framework of relativistic mean-field theory. The results show that trapped neutrinos increase proton fraction and make the equation of state of neutron star matter softer when neglecting hyperonic freedom, while suppress the appearance of hyperons and make the equation of state stiffer when including hyperons in the protoneutron star. The maximum mass, compared with cold neutron star which is in beta equilibrium, decreases by 0.06M⊙ for non-strange protoneutron star while increases by 0.21M ⊙ for protoneutron star with hyperons when the relative number of trapped neutrino is 0.4.

关键词： protoneutron star neutrino equation of state

Developing a process-based and remote sensing driven crop yield model for maize(PRYM–Maize) and its validation over the Northeast China Plain

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Journal of Integrative Agriculture 2021年第2期20卷 408-423页

作者： zhang Sha BAI Yun zhang jia-hua Shahzad ALI School of Automation Qingdao UniversityQingdao 266071P.R.China College of Computer Science and Technology Qingdao UniversityQingdao 266071P.R.China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Spatial dynamics of crop yield provide useful information for improving the production. High sensitivity of crop growth models to uncertainties in input factors and parameters and relatively coarse parameterizations in conventional remote sensing(RS) approaches limited their applications over broad regions. In this study, a process-based and remote sensing driven crop yield model for maize(PRYM–Maize) was developed to estimate regional maize yield, and it was implemented using eight data-model coupling strategies(DMCSs) over the Northeast China Plain(NECP). Simulations under eight DMCSs were validated against the prefecture-level statistics(2010–2012) reported by National Bureau of Statistics of China, and inter-compared. The 3-year averaged result could give more robust estimate than the yearly simulation for maize yield over space. A 3-year averaged validation showed that prefecture-level estimates by PRYM–Maize under DMCS8, which coupled with the development stage(DVS)-based grain-filling algorithm and RS phenology information and leaf area index(LAI), had higher correlation(R, 0.61) and smaller root mean standard error(RMSE, 1.33 t ha^(–1)) with the statistics than did PRYM–Maize under other DMCSs. The result also demonstrated that DVS-based grain-filling algorithm worked better for maize yield than did the harvest index(HI)-based method, and both RS phenology information and LAI worked for improving regional maize yield estimate. These results demonstrate that the developed PRYM–Maize under DMCS8 gives reasonable estimates for maize yield and provides scientific basis facilitating the understanding the spatial variations of maize yield over the NECP.

关键词： process-based and remote sensing model maize yield simulation development stage grain filling harvest index

Safe range analysis of clear distance of twin shallow tunnels based on limit analysis and reliability theory

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Journal of Central South University 2018年第1期25卷 196-207页

作者： zhang Biao WANG Xuan zhang jia-sheng zhang jia-hua CHENG Hao School of Civil Engineering Central South University

A method of analyzing the stability of twin shallow tunnels was presented using both limit analysis with nonlinear failure criterion and reliability *** the condition of nonlinear failure criterion,the critical clear distancesof twin shallow tunnels were obtained by analyzing the change of surrounding pressure.A reliability model was established based on limit state equation,and the failure probability was solved by virtue of Monte Carlo *** factor and corresponding clear distance of different safety levels were obtained by introducing a target reliability *** scope of clear distance for different safety levels is described,which can be used as a supplement and improvement to the design codes of tunnels.

关键词： twin shallow tunnels limit analysis nonlinear failure criterion reliability theory clear distance

Minimum safe thickness of rock plug in karst tunnel according to upper bound theorem

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Journal of Central South University 2016年第9期23卷 2346-2353页

作者： YANG Zi-han zhang jia-hua School of Civil Engineering Central South University Changsha 410075 China

High pressure and water-bearing caverns ahead of a karst tunnel face tend to cause geological disasters, such as water and mud bursts. So, the determination of safe thickness of the reserved rock plug is a key technical problem to be solved for karst tunnel construction. Based on the Hoek-Brown nonlinear failure criterion, the minimum safe thickness of rock plug was investigated in the light of the limit analysis theory. On the basis of the proposed failure mode, the expression of the minimum thickness for rock plug was obtained by means of upper bound theorem in combination with variational principle. The calculation results show the influence of each parameter on safe thickness and reveal the damage range of rock plug. The proposed method is verified by comparing the results with those of the drain cavern of Maluqing Tunnel. The research shows that with the increase of compressive strength and tensile strength as well as constant A of Hoek-Brown criterion, the safe thickness decreases, whereas with the increase of cavern pressure, tunnel diameter, and constant B from Hoek-Brown criterion, the safe thickness increases. Besides, the tensile strength, or constants A and B affect the shear failure angle of rock plug structure, but other parameters do not. In conclusion, the proposed method can predict the minimum safe thickness of rock plug, and is useful for water burst study and prevention measures of tunnels constructed in high-risk karst regions.

关键词： karst tunnels rock plug minimum safe thickness upper limit theorem failure mode

Spectral Reflectance Characteristics of Different Snow and Snow-Covered Land Surface Objects and Mixed Spectrum Fitting

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光谱学与光谱分析 2011年第9期31卷 2499-2502页

作者： zhang jia-hua ZHOU Zheng-ming WANG Pei-juan YAO Feng-mei Liming Yang Chinese Academy of Meteorological Sciences 13eijing 100081 China Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100094 China College of Earth Sciences Chinese Academy of Sciences Beijing 100049 China U.S. Geological Survey Center for Earth Resources Observation and Science Sioux Falls South Dakota 57198 USA

The field spectroradiometer was used to measure spectra of different snow and snow-covered land surface objects in Beijing *** result showed that for a pure snow spectrum,the snow reflectance peaks appeared from visible to 800 nm band locations;there was an obvious absorption valley of snow spectrum near 1 030 nm *** with fresh snow,the reflection peaks of the old snow and melting snow showed different degrees of decline in the ranges of 300～1 300,1 700～1 800 and 2 200～2 300 nm,the lowest was from the compacted snow and frozen *** the vegetation and snow mixed spectral characteristics,it was indicated that the spectral reflectance increased for the snow-covered land types(including pine leaf with snow and pine leaf on snow background), due to the influence of snow background in the range of 350～1 300 ***, the spectrum reflectance of mixed pixel remained a vegetation spectral *** the end,based on the spectrum analysis of snow,vegetation,and mixed snow/vegetation pixels,the mixed spectral fitting equations were established,and the results showed that there was good correlation between spectral curves by simulation fitting and observed ones(correlation coefficient R2=0.950 9).

关键词： Snow Snow-covered land surface object Spectral characteristics Spectral fitting

Modelling the crop yield gap with a remote sensing-based process model:A case study of winter wheat in the North China Plain

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Journal of Integrative Agriculture 2023年第10期22卷 2993-3005页

作者： YANG Xu zhang jia-hua YANG Shan-shan WANG Jing-wen BAI Yun zhang Sha Research Center for Remote Sensing and Digital Earth College of Computer Science and TechnologyQingdao UniversityQingdao 266071P.R.China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094P.R.China

Understanding the spatial distribution of the crop yield gap(YG)is essential for improving crop *** studies have typically focused on the site scale,which may lead to considerable uncertainties when scaled to the regional *** mitigate this issue,this study used a process-based and remote sensing driven crop yield model for winter wheat(PRYM-Wheat),which was derived from the boreal ecosystem productivity simulator(BEPS),to simulate the YG of winter wheat in the North China Plain from 2015 to *** validation based on statistical yield data revealed good performance of the PRYM-Wheat Model in simulating winter wheat actual yield(Ya).The distribution of Ya across the North China Plain showed great heterogeneity,decreasing from southeast to *** remote sensing-estimated results show that the average YG of the study area was 6400.6 kg ha^(–1).The YG of jiangsu Province was the largest,at7307.4 kg ha^(–1),while the YG of Anhui Province was the smallest,at 5842.1 kg ha^(–1).An analysis of the responses of YG to environmental factors showed no obvious correlation between YG and precipitation,but there was a weak negative correlation between YG and accumulated *** addition,the YG was positively correlated with *** general,studying the specific features of the YG can provide directions for increasing crop yields in the future.

关键词： remote sensing PRYM-Wheat Model yield gap environmental factors North China Plain

Seismic reliability analysis of shield tunnel faces under multiple failure modes by pseudo-dynamic method and response surface method

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Journal of Central South University 2022年第5期29卷 1553-1564页

作者： zhang jia-hua XU Peng SUN Wang-cheng LI Bo Work Safety Key Lab on Prevention and Control of Gas and Roof Disasters for Southern Coal Mines Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal MinesHunan University of Science and TechnologyXiangtan 411201China School of Resource Environment and Safety Engineering Hunan University of Science and TechnologyXiangtan 411201China

In order to investigate the stability problem of shield tunnel faces subjected to seismic loading,the pseudodynamic method(P-DM)was employed to analyze the seismic effect on the *** kinds of failure mechanisms of active collapse and passive extrusion were considered,and a seismic reliability model of shield tunnel faces under multifailure mode was *** limit analysis method and the response surface method(RSM)were used together to solve the reliability of shield tunnel faces subjected to seismic *** with existing results,the results of this work are *** effects of seismic load and rock mass strength on the collapse pressure,extrusion pressure and reliability index were discussed,and reasonable ranges of support pressure of shield tunnel faces under seismic action were *** method can provide a new idea for solving the shield thrust parameter under the seismic loading.

关键词： shield tunnel face pseudo-dynamic method seismic effect multi-failure mode support pressure range

17β-Estradiol Regulates SKP2 Expression in Cultured Immature Boar Sertoli Cells Mainly via Estrogen Receptor β,cAMP-PKA and ERK1/2

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Journal of Integrative Agriculture 2014年第4期13卷 827-836页

作者： WANG Xian-zhong ZHU Feng-wei WANG Yong WANG Yi zhang jiao-jiao zhang jia-hua Chongqing Key Laboratory of Forage & Herbivore College of Animal Science and TechnologySouthwest University

Estrogen plays an important role in regulating testicular Sertoli cell number. Furthermore, S-phase kinase-associated protein 2 （SKP2） plays a central role in mammalian cell cycle progression. The objective of this study was to determine whether 17β-estradiol can regulate the expression of SKP2, and the Sertoli cell cycle, via estrogen receptor β （ERβ）, the cyclic adenosine monophosphate （cAMP）-protein kinase A （PKA） and extracellular signal-regulated kinase （ERK1/2） pathway. When cultured immature boar Sertoli cells were treated with 17β-estradiol, a time-dependent increase in SKP2 mRNA and protein level was observed by real-time PCR and Western blot, and 17β-estradiol activity peaked at 30 min. Treatment with ICI182780 and ERβ antagonist reduced 17β-estradiol-induced expression of SKP2 and proliferating cell nuclear antigen （PCNA）, while increasing the protein concentration of p27kip1. However, the effect of ERa antagonist on these parameters was lower than that of ICI 182780 and ERβ. Forskolin had a similar effect as 17β-estradiol on the expression of SKP2, PCNA and p27kip1, Rp-cAMP, H-89 and U0126 treatment reduced 17β-estradiol-induced changes, while H-89 also inhibited ERK1/2 activation. Therefore, 17β-estradiol mainly regulates SKP2 mRNA and protein expression via ERβ-cAMP-PKA and ERK1/2 activation. SKP2 and PCNA expression were positively correlated, while increased SKP2 expression likely resulted in p27kip1 degradation.

关键词： 17β-estradiol Sertoli cell SKP2 estrogen receptor cAMP-PKA ERK1/2