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Initial exploration of the mechanism underlying H2O2-induced root horizontal bending in pea

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Science Bulletin 2015年第14期60卷 1298-1300页

作者： Sheng Li Li-rong Su Shao-Ying ma Zhen-Zhen shi Xiao-Ming Yang Gansu Provincial Key Laboratory of Aridland Crop Science College of Life Science and Technology Gansu Agricultural University Institute of Crop Gansu Academy of Agricultural Sciences

It was reported that exogenous hydrogen peroxide （H2O2） can induce primary root bend in Arabidopsis and pea. However, the mechanism remains unclear. Here we explored the mechanism underlying this phenomenon by using the pea （Pisum sativum L.） variety ＂longwan No. 1＂ The results showed that the endogenous indole-3-acetic acid （IAA） content decreased and gibberellin A3 （GA3） content increased in the curving primary pea root induced by H2O2. Meanwhile, both of the two hormones asymmetrically distributed in the inside and outside parts of the curving root. Also, the starch content decreased due to the increased a-amylase activity in this process. However, exogenous Ca2＋ can relieve the horizontal bending of pea root induced by H2O2 and altered the contents of endogenous IAA and GA3. A working model was proposed： Exogenous H2O2 causes the increase in GA3 content, and GA3 stimulates the activity of or-amylase, which leads to the hydrolysis of starch, and then the root lost the gravity perceiving. The asymmetric distribution of IAA and GA3 in two sides of curving root may cause the horizontal *** Ca^2＋ can relieve root bending through altering the endogenous IAA and GA3 contents.

关键词： Gravitropism Exogenous H2O2Horizontal bending Primary pea root

Numerical investigation on aerodynamic performance of a bionic flapping wing

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Applied mathematics and Mechanics(English Edition) 2019年第11期40卷 1625-1646页

作者： Xinghua CHANG Laiping ZHANG rong ma Nianhua WANG State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000Sichuan ProvinceChina Computational Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000Sichuan ProvinceChina

This paper numerically studies the aerodynamic performance of a bird-like bionic flapping *** geometry and kinematics are designed based on a seagull wing,in which flapping,folding,swaying,and twisting are *** in-house unsteady flow solver based on hybrid moving *** adopted for unsteady flow *** focus on two main issues in this study,i.e.,the influence of the proportion of down-stroke and the effect of span-wise *** results show that the proportion of downstroke is closely related to the efficiency of the flapping *** preferable proportion is about 0.7 by using the present geometry and kinematic model,which is very close to the observed *** finding is that the drag and the power consumption can be greatly reduced by the proper span-wise *** cases with different reduced frequencies are simulated and compared with each *** numerical results show that the power consumption reduces by more than 20%,and the drag coefficient reduces by more than 60% through a proper twisting motion for both *** flow mechanism is mainly due to controlling of unsteady flow separation by adjusting the local effective angle of *** conclusions will be helpful for the high-performance micro air vehicle (maV) design.

关键词： flapping wing bird-like flapping unsteady flow radial basis function (RBF) hybrid dynamic mesh span-wise twisting mechanism

Dependence Rayleigh competing risks model with generalized censored data

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Journal of Systems Engineering and Electronics 2020年第4期31卷 852-858页

作者： WANG Liang ma Jin’ge shi Yimin School of mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China School of mathematics Yunnan Normal UniversityKunming 650500China School of mathematics and Statistics Xidian UniversityXi’an 710071China Department of Applied mathematics Northwestern Polytechnical UniversityXi’an 710072China

The inference for the dependent competing risks model is studied and the dependent structure of failure causes is modeled by a marshall-Olkin bivariate Rayleigh distribution. Under generalized progressive hybrid censoring(GPHC), maximum likelihood estimates are established and the confidence intervals are constructed based on the asymptotic theory. Bayesian estimates and the highest posterior density credible intervals are obtained by using Gibbs sampling. Simulation and a real life electrical appliances data set are used for practical illustration.

关键词： dependence competing risks bivariate distribution generalized progressive hybrid censoring(GPHC) likelihood estimation Bayesian analysis

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秦汉时期乡村借贷新探

史学集刊 2025年第1期 75-87页

作者：马新山东大学历史学院山东济南250100

秦汉乡村借贷既非古典借贷,亦非严格意义上的高利贷,它只是被当时乡村社会所普遍接受的特有借贷形式。这一借贷形式具有较强内循性,多以乡村居民间借贷为主,富商大贾以及城市商业资本难以介入;也有较强应急性,多是乡村居民生存急需时的... 详细信息

秦汉乡村借贷既非古典借贷,亦非严格意义上的高利贷,它只是被当时乡村社会所普遍接受的特有借贷形式。这一借贷形式具有较强内循性,多以乡村居民间借贷为主,富商大贾以及城市商业资本难以介入;也有较强应急性,多是乡村居民生存急需时的借贷行为,经营性或扩大再生产的借贷颇为少见;还有较强行政性,王朝官方既是重要放贷方,又是监管者与仲裁人,直接介入乡村经济事务。这些特点减少了商品经济对乡村社会的冲击,在一定时期内有利于乡村社会发展与繁荣。但是,从长时段视角看,它也影响乡村社会对外来经济要素的接纳,制约乡村社会进一步发展,使其长期处于简单再生产的循环之中。

关键词：秦汉乡村社会借贷关系

Thermally activated delayed fluorescence enhanced by macrocyclization

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Science China Chemistry 2025年

作者： Shuo Li Chenghao Zhu Lijun mao Xin Zhang Zecong Ye Chunju Li Da ma School of Pharmaceutical and Chemical Engineering & Institute for Advanced Studies Taizhou University School of Chemical Engineering and Light Industry Guangdong University of Technology Tianjin Key Laboratory of Structure and Performance for Functional Molecules Tianjin Normal University

Thermally activated delayed fluorescence (TADF) depends on reverse intersystem crossing (RISC) from the lowest triplet to the singlet excited state. Here, a macrocyclization strategy is developed to achieve TADF emission by promoting RISC. 5-(9Hcarbazol-9-yl) isophthalonitrile, a fluorescent molecule, is coupled with 1,4-dimethoxybenzene by methylene bridges to form a macrocycle with TADF emission. Experimental results and theoretical calculation indicate that the macrocyclization strategy contributes to RISC promotion and suppression of nonradiative decay, resulting in effective TADF emission transformed from prompt fluorescence. Three TADF luminophores are cyclized with the same strategy, and an enhanced TADF emission of up to3.8 folds is observed. The marriage of macrocycle chemistry and luminescent materials will provide new guidelines for designing efficient TADF materials.

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Multi-dimensional Bi@C electrocatalyst for Cr3+/Cr2+ redox reaction boosting high-performance iron-chromium flow batteries

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Science China Chemistry 2025年

作者： Min Wu Mingjun Nan Shumin Liu Caihe Zhong Lin Qiao Huamin Zhang Xiangkun ma Department of materials Science and Engineering Dalian Maritime University Division of Energy Storage Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences

With the increasing demand for energy storage technology, iron-chromium flow batteries（ICFBs） have been widely concerned because of their price advantage. However, the low electrochemical activity of Cr3+/Cr2+redox couples and the side hydrogen evolution reaction limit the industrial application of ICFBs. A multi-dimensional Bi/carbon composite electrocatalyst（Bi@C）for ICFB is designed and prepared to improve the electrochemical activity of Cr3+/Cr2+redox couples. Benefiting by using the Bimetal organic framework（Bi-MOF） with solid matrix as precursors, Bi nanospheres are highly dispersed on the Bi@C electrocatalyst that effectively enhances the electrochemical activity. The special morphology of Bi@C electrocatalyst helps the transfer of electrons and ions, significantly reducing the polarization of battery. Herein, the 3D porous carbon frames accelerate mass transfer, and the 2D carbon nanobelts and carbon layer coating on 0D Bi nanospheres improve the conductivity of Bi nanospheres. Therefore, the ICFB with multi-dimensional Bi@C electrocatalyst exhibits coulombic efficiency of 98.10% and energy efficiency of 79.14% at 140 ma cm-2, which is higher than ICFBs with commercial graphite carbon electrocatalyst and with heat treatment carbon felt. This work provides a simple and economical method to fabricate a high-performance multidimensional Bi@C electrocatalyst for Cr3+/Cr2+redox couples, boosting the development of ICFBs.

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Alleviation of mycotoxin biodegradation agent on zearalenone and deoxynivalenol toxicosis in immature gilts

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Journal of Animal Science and Biotechnology 2018年第3期9卷 727-737页

作者： Donghui shi Jianchuan Zhou Lihong Zhao Xiaoping rong Yu Fan Humera Hamid Wenqiang Li Cheng Ji Qiugang ma State Key Laboratory of Animal Nutrition China Agricultural UniversityBeijing 100193People’s Republic of China Liaoning Medical University Jinzhou 121001People’s Republic of China Fuqing Fengze Agricultural Science and Technology Development Co.Ltd. Fuzhou 350011People’s Republic of China State Key Laboratory of Direct-Fed Microbial Engineering Beijing 100193People’s Republic of China

Background: The current study was carried out to evaluate the effects of mycotoxin biodegradation agent(MBA, composed of Bacillus subtilis ANSB01 G and Devosia sp. ANSB714) on relieving zearalenone(ZEA) and deoxynivalenol(DON) toxicosis in immature ***: A total of forty pre-pubertal female gilts(61.42 ± 1.18 kg) were randomly allocated to four diet treatments: CO(positive control); MO(negative control, ZEA 596.86 μg/kg feed and DON 796 μg/kg feed);COA(CO + 2 g MBA/kg feed); MOA(MO + 2 g MBA/kg feed). Each treatment contained 10 replicates with 1 gilt per replicate. Gilts were housed in an environmentally controlled room with the partially slatted ***: During the entire experimental period of 28 d, average daily gain(ADG) and average daily feed intake(ADFI)of gilts in MO group was significantly reduced compared with those in CO group. The vulva size of gilts was significantly higher in MO group than CO group. In addition, significant increases in the plasma levels of Ig A,Ig G, IL-8, IL-10 and PRL were determined in MO group compared with that in CO group. ZEA and DON in the diet upregulated apoptotic caspase-3 in ovaries and uteri, along with down-regulated the anti-apoptotic protein Bcl-2 in ovaries. The supplementation of MBA into diets co-contaminated with ZEA and DON significantly increased ADG, decreased the vulva sizes, reduced the levels of Ig G, IL-8 and PRL in plasma, and regulated apoptosis in ovaries and uteri of ***: The present results indicated that feeding diet contaminated with ZEA and DON simultaneously(596.86 μg/kg + 796 μg/kg) had detrimental effects on growth performance, plasma immune function and reproductive status of gilts. And MBA could reduce the negative impacts of these two toxins, believed as a promising feed additive for mitigating toxicosis of ZEA and DON at low levels in gilts.

关键词： Apoptosis Deoxynivalenol Mycotoxin biodegradation agent Serum parameter Vulva size Zearalenone

Accurate manipulation of anthropomorphic robotic arm based on 3D human eye gazing with posture error compensation

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Science China Technological Sciences 2025年

作者： Quanlin LI Xianzong WANG Jiaji ma Qianjun HUANG Qizhi JIANG Wenbin CHEN Caihua XIONG State Key Laboratory of Intelligent manufacturing Equipment and Technology School of Mechanical Science and Engineering Huazhong University of Science and Technology Institute of Medical Equipment Science and Engineering Huazhong University of Science and Technology

As humans and robots work closer together than ever, anthropomorphic robotic arms with intuitive human-robot interaction interfaces have drawn massive attention to improving the quality of robot-assisted manipulation. In pursuit of this,we designed a dedicated 7-degrees-of-freedom (DoF) anthropomorphic robotic arm having three compact differential joints and a head-mounted gaze tracker enabling head-pose-tracked 3D gaze estimation. Moreover, two key challenges were addressed to achieve accurate robot-assisted manipulation of the object indicated by the direction of human gaze. First, a novel predictive pupil feature was proposed for 3D gaze estimation. Differing from most existing features subjected to the common paraxial approximation assumption, the proposed novel predictive pupil feature considered the light refraction at two corneal surfaces with a more realistic eye model, significantly improving the 3D gaze estimation accuracy when the eyeball rotates at large angles. Second, a novel optimization-based approach was developed to efficiently compensate for the posture errors of the designed 7-DoF anthropomorphic robotic arm for accurate manipulation. Compared with the existing Jacobian-based or optimization-based approaches with nominal joint values as iteration initial, the proposed approach computed the optimal iteration initial and realized faster convergence for real-time posture error compensation. With the posture error compensation in real time and 3D gaze estimated accurately, the human can command accurate robot-assisted manipulation using his eyes intuitively. The proposed system was successfully tested on five healthy subjects.

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不同运动强度与骨关节炎发病风险的效应分析

中国组织工程研究 2025年第6期29卷 1305-1311页

作者：马浩宇乔鸿超郝茜茜史冬博太原理工大学体育学院山西省晋中市030600

背景:越来越多的证据表明不同运动强度与骨关节炎风险之间存在关联,但这可能受到混杂和反向因果关系的影响,结论尚未统一。目的:应用孟德尔随机化探索不同运动强度与骨关节炎的因果关联。方法:选取与不同运动强度相关联的全基因组关联... 详细信息

背景:越来越多的证据表明不同运动强度与骨关节炎风险之间存在关联,但这可能受到混杂和反向因果关系的影响,结论尚未统一。目的:应用孟德尔随机化探索不同运动强度与骨关节炎的因果关联。方法:选取与不同运动强度相关联的全基因组关联研究数据,以阈值P<5×10-8筛选工具变量,采用孟德尔随机化5种分析方法评估暴露与结局风险的因果关系,以逆方差加权法作为主要分析方法。使用选定的工具变量来评估不同运动强度与骨关节炎的因果关联,并进行敏感性分析与反向孟德尔随机化分析。结果与结论:①逆方差加权法分析结果显示,低强度运动对膝骨关节炎的保护效应显著(OR=0.14,95%CI:0.06-0.32,P<0.001),久坐行为(例如电视观看)是膝骨关节炎和髋骨关节炎的危险因素(OR=2.24,95%CI:1.74-2.88,P<0.001;OR=1.34,95%CI:1.01-1.78,P=0.04)。对于骨关节炎与不同运动强度的反向孟德尔随机化分析发现,骨关节炎与低强度运动呈负相关性,与电视观看呈正相关。②分析结果显示,不同运动强度与骨关节炎风险存在双向因果关系。

关键词：运动强度骨关节炎孟德尔随机化因果关联膝骨关节炎髋骨关节炎