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The foxtail millet Si69 gene is a Wali7 (wheat aluminum-induced protein 7) homologue and may function in aluminum tolerance

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Chinese Science Bulletin 2009年第10期54卷 1697-1706页

作者： zhao LinNa zhao Qian AO GuangMing YU JingJuan State Key Laboratory for Agro-Biotechnology College of Biological Sciences China Agricultural University Beijing 100193 China

We isolated a clone, named Si69, from a foxtail millet immature seed cDNA library. The protein encoded by Si69 contains a conserved Wali7 (wheat aluminum induced protein 7) domain and shares high-level homology with aluminum-induced proteins from other species including rice and Arabidopsis. The Si69 gene presents as a single locus in foxtail millet genome and is globally expressed in all tissues examined. Its expression is up-regulated by aluminum. The sequence feature and expression pattern suggest that the Si69 gene is involved in aluminum tolerance or detoxification. To confirm its biological functions, Si69 controlled by the CaMV35S promoter was introduced into Arabidopsis. Transgenic plants did not show any visible morphological changes compared to wild-type plants under normal growth conditions. However, when treated with 20 or 50 μmol/L Aluminum (Al), the root apices of wild-type plants were heavily stained by hematoxylin, whereas those of Si69 transgenic plants were not stained when treated with 20 μmol/L Al and slightly stained when treated with 50 μmol/L Al. Scanning electron microscopy (SEM) results further demonstrated that the damage of the root apices was se- verer in wild-type plants than in transgenic plants. Inhibition of root growth and accumulation of malondialdehyde (MDA), an indicator of lipid peroxidation, were lower in transgenic plants than in wild-type plants. The results show that overexpression of Si69 may increase Al tolerance in transgenic plants, indicating that a series of Wali7-containing genes may play similar roles in Al tolerance/detoxification.

关键词： Si69 诱导蛋白耐铝性基因组同源性谷子小麦转基因植物

Curvature Compensated CMOS Bandgap Reference with Novel Process Variation Calibration Technique

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Journal of Beijing Institute of Technology 2018年第2期27卷 182-188页

作者： Jiancheng Zhang Mao Ye Yiqiang zhao Gongyuan zhao Tianjin Key Laboratory of Imaging and Sensing Microelectronic Technology Tianjin UniversityTianjin 300072China Tianjin Infrared Imaging Technology Engineering Center Tianjin 300072China

A lowtemperature coefficient（ TC） bandgap reference（ BGR） with novel process variation calibration technique is proposed in this paper. This proposed calibration technique compensating both TC and output value of BGR achieves fine adjustment step towards the reference voltage,while keeping optimal TC by utilizing large resistance to help layout match. The high-order curvature compensation realized by poly and p-diffusion resistors is introduced into the design to guarantee the temperature characteristic. Implemented in 180 nm technology,the proposed BGR has been simulated to have a power supply rejection ratio（ PSRR） of 91 dB@100 Hz. The calibration technique covers output voltage scope of 0. 49 V-0. 56 Vwith TC of 9. 45 × 10^（-6）/℃-9. 56 × 10^（-6）/℃ over the temperature range of-40 ℃-120 ℃. The designed BGR provides a reference voltage of 500 mV,with measured TC of 10. 1 × 10^（-6）/℃.

关键词： bandgap reference voltage process variation resistance-trimming current-calibration curvature compensation temperature coefficient

CFD calculations on the unsteady aerodynamic characteristics of a tilt-rotor in a conversion mode

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Chinese Journal of Aeronautics 2015年第6期28卷 1593-1605页

作者： Li Peng zhao Qijun Zhu Qiuxian National Key Laboratory of Science and Technology on Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics

In order to calculate the unsteady aerodynamic characteristics of a tilt-rotor in a conver- sion mode, a virtual blade model （VBM） and an real blade model （RBM） are established respec- tively. A new multi-layer moving-embedded grid technique is proposed to reduce the numerical dissipation of the tilt-rotor wake in a conversion mode. In this method, a grid system generated abound the rotor accounts for rigid blade motions, and a new searching scheme named adaptive inverse map （AIM） is established to search corresponding donor elements in the present moving- embedded grid system to translate information among the different computational zones. A dual-time method is employed to fulfill unsteady calculations on the flowfield of the tilt-rotor, and a second-order centered difference scheme considering artificial viscosity is used to calculate the flux. In order to improve the computing efficiency, the single program multiple data （SPMD） model parallel acceleration technology is adopted, according to the characteristic of the current grid system. The lift and drag coefficients of an NACA0012 airfoil, the dynamic pressure distributions below a typical rotor plane, and the sectional pressure distributions on a three-bladed Branum- Tung tilt-rotor in hover flight are calculated respectively, and the present VBM and RBM are val- idated by comparing the calculated results with available experimental data. Then, unsteady aero- dynamic forces and flowfields of an XV-15 tilt-rotor in different modes, such as a fixed conversion mode at different tilt angles （15°, 30°, 60°） and a whole conversion mode which converses from 0° to 90°, are numerically simulated by the VBM and RBM respectively. By analyses and comparisons on the simulated results of unsteady aerodynamic forces of the tilt-rotor in different modes, some meaningful conclusions about distorted blade-tip vortex distribution and unsteady aerodynamic force variation in a conversion mode are obtained, and these investigation

关键词： CFD Conversion mode Multi-layer moving-embedded grid Tilt-rotor Unsteady flowfield

Shoot and root traits in drought tolerant maize(Zea mays L.) hybrids

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Journal of Integrative Agriculture 2018年第5期17卷 1093-1105页

作者： zhao Jin XUE Qing-wu Kirk E Jessup HOU Xiao-bo HAO Bao-zhen Thomas H Marek XU wen-wei Steven R Evett Susan A O'Shaughnessy David K Brauer Texas A&M AgriLife Research and Extension Center at Amarillo TX 79106 USA department of Soil Water and Environmental Sciences University of Arizona AZ 85721 USA School of Science and Technology Xinxiang University Xinxiang 453003 P.R.China Texas A&M AgriLife Research and Extension Center at Lubbock TX 79403 USA USDA-ARS Conservation and Production Research Laboratory TX 79012 USA

This study aimed to investigate the differences in shoot and root traits, and water use and water use efficiency（WUE） in drought tolerant（DT） maize（Zea mays L.） hybrids under full and deficit irrigated conditions. A two-year greenhouse study was conducted with four hybrids（one conventional hybrid, 33D53AM, two commercial DT hybrids, P1151 AM, N75H, and an experimental hybrid, Exp HB） grown under two water regimes（I（100） and I（50）, referring to 100 and 50% of evapotranspiration requirements）. Under water stress, the hybids P1151 AM, N75, and Exp HB showed more drought tolerance and had either greater shoot dry weight or less dry weight reduction than the conventional hybrid（33 D53 AM）. However, these three hybrids responded to water stress using different mechanisms. Compared with the conventional hybrid, the two commercial DT hybrids（P1151 AM and N75H） had a smaller leaf area, shoot dry weight, and root system per plant. As a result, these hybrids used less water but had a higher WUE compared with the conventional hybrid. In contrast, the experimental hybrid（ExpHB） produced more shoot biomass by silking stage at both irrigation levels than all other hybrids, but it had relatively lower WUE. The hybrids demonstrated different drought response mechanisms that may require different irrigation management strategies. More investigation and validation are needed under field conditions and in different soil types.

关键词： drought tolerant hybrid rooting characteristics water use water use efficiency

Numerical simulation of quasi-static compression on a complex rubber foam

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Acta Mechanica Solida Sinica 2017年第3期30卷 285-290页

作者： Huyi Wang wenjun Hu Fengpeng zhao Institute of Systems Engineering CAEP Mianyang 621900 China

A complex rubber foam under quasi-static compression is simulated using the finite element method （FEM）, The present work sets up the phenomenological constitutive model for the silicon rubber, The computerized tomography （CT） technique is utilized to reconstruct the real complex foam geometries, The quasi-static uniaxial compression on the foam is simulated in ABAQUS. The present work obtains the stress response as the nominal strain nearly reaches 80% and the foam exhibits hyper-elastic behavior, The FEM results achieve good agreements with the data obtained from the multi-scale simulation and the tests as the nominal strain is less than 60%.

关键词： Complex Rubber Foam Quasi-static Compression

DYNAMIC MOdeLING AND ACTIVE CONTROL OF FLEXIBLE PLATE BASED ON THE INPUT-OUTPUT DATA

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Acta Mechanica Solida Sinica 2013年第3期26卷 255-262页

作者： Yong Xie Tong zhao Guoping Cai department of Engineering Mechanics State Key Laboratory of Ocean EngineeringShanghai Jiaotong University

This paper studies the low-order dynamic modeling and active control of a flexible plate and provides experimental verification. First based on the input-output data of the sys- tem, the Markov parameters of the system are identified using the method of observer/Kalman filter identification （OKID）. Then a low-order state-space model is built using the eigensystem realization algorithm （ERA）. Finally, a linear quadratic Gaussian （LQG） controller is designed based on the low-order state-space model. Experimental results have proved the effectiveness and feasibility of the research.

关键词： flexible plate OKID ERA active control experiment

Intravenous injection of mesenchymal stem cells is effective in treating liver fibrosis

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World Journal of Gastroenterology 2012年第10期18卷 1048-1058页

作者： Wei zhao Jun-Jie Li Da-Yong Cao Xiao Li Lin-Ying Zhang Yong He Shu-Qiang Yue de-Sheng Wang Ke-Feng Dou department of Hepatobiliary Surgery Xijing HospitalThe Fourth Military Medical UniversityXi'an 710032Shaanxi ProvinceChina

AIM: To compare the influence of different transplant sites in bone marrow mesenchymal stem cell (MSC)-based therapy for liver fibrosis. METHODS: MSCs isolated from Sprague Dawley (SD) rats were induced into hepatocyte-like cells. Liver fibrosis in SD rats was induced with carbon tetrachloride. Following hepatocyte induction in vitro, 4',6-diamidino- 2-phenylindole (DAPI)-labeled MSCs were transplanted by intravenous, intrahepatic, and intraperitoneal injection. Histopathological staining, immunohistochemistry, and biochemical analysis were used to compare the morphological and functional liver regeneration among different MSC injection modalities. The expression differences of interleukins, growth factor, extracellular matrix, matrix metalloproteinases, and tissue inhibitor of metalloproteinase were examined by real-time reverse transcription-polymerase chain reaction (RT-PCR) andenzyme linked immunosorbent assay (ELISA). RESULTS: Four days after exposure to hepatocyte differentiation medium, MSCs that did not express hepatocyte markers could express α-fetoprotein, albumin, and cytokeratin 18. The results of histopathological staining, immunohistochemistry, and biochemical analysis indicated that intravenous injection is more effective at rescuing liver failure than other injection modalities. DAPI-labeled cells were found around liver lobules in all three injection site groups, but the intravenous group had the highest number of cells. PCR and ELISA analysis indicated that interleukin-10 (IL-10) was highest in the intravenous group, whereas il1β, il6, tnfα and tgfβ, which can be regulated by IL10 and are promoters of liver fibrosis, were significantly lower than in the other groups. CONCLUSION: MSC administration is able to protect against liver fibrosis. Intravenous injection is the most favorable treatment modality through promotion of IL10 expression.

关键词： Mesenchymal stem cells Hepatocyte differentiation Intravenous injection Liver fibrosis Interleukin-10

BLOCK BASED NEWTON-LIKE BLENDING INTERPOLATION

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Journal of Computational Mathematics 2006年第4期24卷 515-526页

作者： Qian-jin zhao Jie-qing Tan School of Computer and Information Hefei University of Technology Hefei 230009 China department of Mathematics and Physics Anhui University of Science and Technology Huainan 232001 China Institute of Applied Mathematics Hefei University of Technology Hefei 230009 China

Newton＇s polynomial interpolation may be the favourite linear interpolation in the sense that it is built up by means of the divided differences which can be calculated recursively and produce useful intermediate results. However Newton interpolation is in fact point based interpolation since a new interpolating polynomial with one more degree is obtained by adding a new support point into the current set of support points once at a time. In this paper we extend the point based interpolation to the block based interpolation. Inspired by the idea of the modern architectural design, we first divide the original set of support points into some subsets （blocks）, then construct each block by using whatever interpolation means, linear or rational and finally assemble these blocks by Newton＇s method to shape the whole interpolation scheme. Clearly our method offers many flexible interpolation schemes for choices which include the classical Newton＇s polynomial interpolation as its special case. A bivariate analogy is also discussed and numerical examples are given to show the effectiveness of our method.

关键词： Interpolation Block based divided differences Blending method.

Combining Endometrium Sampling device and SurePath Preparation to Screen for Endometrial Carcinoma： A Validation Study

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Chinese Medical Journal 2015年第5期128卷 648-653页

作者： Jia wen Rui Chen Jian zhao Yin Dong Xi Yang Qin-Ping Liao department of Obstetrics and Gynecology Peking University First Hospital Beijing 100034 China department of Pathology Peking University First Hospital Beijing 100034 China

Background：The aim of this study was to compare specimen adequacy of SAP-I provided for cytology with that of dilation and curettage （D ＆ C） or hysteroscopy for histology,and evaluate the accuracy of combining endometrium sampling by SAP-1 and liquid-based cytology using SurePath preparation for screening endometrial carcinoma and its ***：Endometrial specimens from women （n =1514） with risk factors were obtained using an SAP-l device for cytological analysis; histological samples were obtained from 375 of these women who underwent D ＆ C or *** specimens were prepared to liquid-based smear using SurePath technology and stained by *** samples were processed in routine pathology and stained by hematoxylin and ***：Adequate specimens for cytology were obtained from 1458/1541 patients （96.3%）,while adequate samples for pathology were obtained from 285/375 patients （76%）.However,for postmenopausaI women,1006 of 1045 cytology （86.3%） were adequate,153 of 238 histology （64.3%） were adequate,it was easier to collect cytological specimens than histological specimens （P 〈 0.05）.The accuracy of endometrial cytology for detecting endometrial carcinoma and its precursor was 92.4% （sensitivity,73%; specificity,95.8%; positive predictive value,75%; and negative predictive value,95.3%）.Conclusions：Endometrial cytology using SAP-1 sampling and SurePath preparation may be a reliable approach for screening patients with endometrial carcinoma and its precursor.

关键词： Diagnostic Accuracy Endometrial Carcinoma Liquid-based Cytology Specimen Adequacy