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Characterization of tub_4^(P287L), a β-tubulin mutant,revealed new aspects of microtubule regulation in shade

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Journal of Integrative Plant Biology 2015年第9期57卷 757-769页

作者： Jie Yu Hong Qiu Xin Liu meiling wang Yongli Gao Joanne Chory Yi Tao School of Life Sciences Xiamen Plant Genetics Key Laboratory Xiamen University State Key Laboratory of Cellular Stress Biology Xiamen University Howard Hughes Medical Institute The Salk Institute for Biological Studies Plant Biology Laboratory The Salk Institute for Biological Studies

When sun plants, such as Arabidopsis thaliana, are under canopy shade, elongation of stems/petioles will be induced as one of the most prominent responses. Plant hormones mediate the elongation growth. However, how environmental and hormonal signals are translated into cell expansion activity that leads to the elongation growth remains elusive. Through forward genetic study, we identi-fied shade avoidance2 (sav2) mutant, which contains a P287L mutation in b-TUBULIN 4. Cortical microtubules (cMTs) play a key role in anisotropic cell growth. Hypocotyls of sav2 are wild type-like in white light, but are short and highly swollen in shade and dark. We showed that shade not only induces cMT rearrangement, but also affects cMT stability and dynamics of plus ends. Even though auxin and brassinosteroids are required for shade-induced hypocotyl elongation, they had little effect on shade-induced rearrangement of cMTs. Blocking auxin transport suppressed dark phenotypes of sav2, while overexpressing EB1b-GFP, a microtubule plus-end binding protein, rescued sav2 in both shade and dark, suggesting that tub4P287L represents a unique type of tubulin mutation that does not affect cMT function in supporting cell elongation, but may affect the ability of cMTs to respond properly to growth promoting stimuli.

关键词： Arabidopsis microtubules plant hormones shade

Effects of multi-sequence combination forces on creep characteristics of bales during wheat harvesting

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 88-99页

作者： Zhong Tang Yaquan Liang Ben Zhang meiling wang Hao Zhang Yaoming Li Key Laboratory of Modern Agricultural Equipment and Technology of Ministry of Education Jiangsu UniversityZhenjiang 212013JiangsuChina

During the baling operation,the wheat stalks are subjected to various mechanisms in the baler and the main form is *** the wheat stem is forced by a combination of the threshing cylinder,it needs to be formed under the action of straw baler and meet transport *** paper mainly studies the properties of wheat stalks when baling,and proposes the application of the creep after-effect theory during the baling *** tension-compression tester was used to perform a 50 mm stalk mechanical test,50 mm stalk static pressure test,35 mm×40 mm×50 mm stalk module static pressure test and bale static pressure *** measured elastic modulus of the stem sample was 7.59 MPa,and the elastic modulus of the inner core of the stem was 8.24 *** return curve of the single stalk and the bale is consistent with the initial creep and steady-state creep in the creep after-effect theory.A logarithmic function was used for fitting of the first stage with coefficient of determination R2=0.8364,and a linear function was used for fitting of the second stage with coefficient of determination R2=*** high water content static pressure test suggests that the load in the loading direction is the coupled load of the working load of the hydraulic cylinder and the internal stress of the *** harvesting wheat stalks with high moisture content,the density parameter of the bale can be appropriately increased while the load parameter of the hydraulic cylinder can be considered unchanged or even *** adjustment of density and load can still ensure the forming quality of the bale.

关键词： baler rheological properties wheat stalk mechanical properties

On Weighted L^p-Approximation by Weighted Bernstein-Durrmeyer Operators

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Analysis in Theory and Applications 2018年第1期34卷 1-16页

作者： meiling wang Dansheng Yu Dejun Zhao Department of Mathematics Hangzhou Normal University College of Fundamental Studies Shanghai University of Engineering Science

In the present paper, we establish direct and converse theorems for weight-ed Bernstein-Durrmeyer operators under weighted L^p-norm with Jacobi weight w（x）=x^a（1-x）β.All the results involved have no restriction a,β〈1-1/p,which indicates that the weighted Bemstein-Durrmeyer operators have some better approxi- mation properties than the usual Bernstein-Durrmeyer operators.

关键词： Weighted Lp-approximation weighted Bernstein-Durrmeyer operators direct andconverse theorems.

In-situ Mg_(77)Cu_(12)Zn_5Y_6 bulk metallic glass matrix composite with extraordinary plasticity

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Chinese Science Bulletin 2006年第2期51卷 229-234页

作者： HUI Xidong DONG Wei wang meiling LIU Xiongjun YU Jialing CHEN Guoliang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

We report experimental evidence of in-situ Mg77Cu12Zn5Y6 bulk metallic glass (BMG) ma- trix composite with extraordinary plastic strain of 18.5% and specific strength of 4.31×105 N·m·kg?1, which are the highest plasticity and specific strength in Mg base BMG alloys reported to date. The excel- lent mechanical properties are attributed to the for- mation of the composite structure which is composed of amorphous matrix and hexagonal-close-packed (hcp) Mg solid solution needle phase with a width less than 500 nm. As plastic phase, the Mg needles not only possess the capability of deformation but also have work hardening phenomenon effect. They give rise to multiple shear bands, and hinder the propagation of local shear band in amorphous matrix.

关键词： Mg77Cu12Zn5Y6 金属玻璃定向凝固共晶体复合材料塑性强度系数

Chemical vapor deposition synthesis of intrinsic van der Waals ferroelectric SbSI nanowires

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Nano Research 2024年第11期17卷 9756-9763页

作者： Longyi Fu Yang Zhao Dapeng Li Weikang Dong Ping wang Jijian Liu Denan Kong Lin Jia Yang Yang meiling wang Shoujun Zheng Yao Zhou Jiadong Zhou Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE) School of Physics Beijing Institute of Technology Beijing 100081 China School of Instrumentation and Optoelectronic Engineering Beihang University Beijing 100081 China College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 China Advanced Research Institute of Multidisciplinary Science and School of Chemistry and Chemical Engineering Beijing Institute of Technology Beijing 100081 China

Intrinsic ferroelectric materials play a critical role in the development of high-density integrated device. Despite some two-dimensional (2D) ferroelectrics have been reported, the research on one-dimensional (1D) intrinsic ferroelectric materials remains relatively scare since 1D atomic structures limit their van der Waals (vdW) epitaxy growth. Here, we report the synthesis of 1D intrinsic vdW ferroelectric SbSI nanowires via a confined-space chemical vapor deposition. By precisely controlling the partial vapor pressure of I2 and reaction temperature, we can effectively manipulate kinetics and thermodynamics processes, and thus obtain high quality of SbSI nanowires, which is determined by Raman spectroscopy and high-resolution scanning transmission electron microscopy characterizations. The ferroelectricity in SbSI is confirmed by piezo-response force microscopy measurements and the ferroelectric transition temperature of 300 K is demonstrated by second harmonic generation. Moreover, the in-plane polarization switching can be maintained in the thin SbSI nanowires with a thickness of 20 nm. Our prepared 1D vdW ferroelectric SbSI nanowires not only enrich the vdW ferroelectric systems, but also open a new possibility for high-power energy storage nanodevices.

关键词： SbSI chemical vapor deposition one-dimensional(1D) ferroelectricity second harmonic generation thermodynamic and kinetics

A petunia transcription factor, PhOBF1, regulates flower senescence by modulating gibberellin biosynthesis

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Horticulture Research 2023年第4期10卷 38-52页

作者： Xiaotong Ji Ziwei Xin Yanping Yuan meiling wang Xinyi Lu Jiaqi Li Yanlong Zhang Lixin Niu Cai-Zhong Jiang Daoyang Sun College of Landscape Architecture and Arts Northwest A&F UniversityYanglingShaanxi 712100China Department of Plant Sciences University of CaliforniaDavisDavisCA 95616USA Crops Pathology and Genetics Research Unit USDA-ARSDavisCA 95616USA

Flower senescence is commonly enhanced by the endogenous hormone ethylene and suppressed by the gibberellins(GAs)in ***,the detailed mechanisms for the antagonism of these hormones during f lower senescence remain *** this study,we characterized one up-regulated gene PhOBF1,belonging to the basic leucine zipper transcription factor family,in senescing petals of petunia(Petunia hybrida).Exogenous treatments with ethylene and GA3 provoked a dramatic increase in PhOBF1 *** with wild-type plants,PhOBF1-RNAi transgenic petunia plants exhibited shortened f lower longevity,while overexpression of PhOBF1 resulted in delayed flower *** abundances of two senescence-related genes PhSAG12 and PhSAG29 were higher in PhOBF1-silenced plants but lower in PhOBF1-overexpressing *** and overexpression of PhOBF1 affected expression levels of a few genes involved in the GA biosynthesis and signaling pathways,as well as accumulation levels of bioactive GAs GA1 and *** of GA3 restored the accelerated petal senescence to normal levels in PhOBF1-RNAi transgenic petunia lines,and reduced ethylene release and transcription of three ethylene biosynthetic genes PhACO1,PhACS1,and ***,PhOBF1 was observed to specifically bind to the PhGA20ox3 promoter containing a G-box *** silencing of PhGA20ox3 in petunia plants through tobacco rattle virus-based virus-induced gene silencing method led to accelerated corolla *** results suggest that PhOBF1 functions as a negative regulator of ethylene-mediated f lower senescence by modulating the GA production.

关键词： senescence pet flower

Tianjin's Nankai District Advances

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China Today 2005年第12期54卷 72-77页

作者： WU meiling wang NAN

TIANJIN is the municipality closest to Beijing. It is the economic center of the Bohai Sea Rim Area and the largest open seaportin northern China. After being made a treaty port in the middle of the 19th century it gradually developed into northern China＇s biggest financial and commercial center. Nankai, Tianjin＇s bustling urban district, characterized by its commerce and culture, is tailor-made for integrated development.

关键词：天津南开区区域经济产业结构文化建设

On Weighted Approximation by Modified Bernstein Operators for Functions with Singularities

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Analysis in Theory and Applications 2014年第4期30卷 405-416页

作者： meiling wang Dansheng Yu Department of Mathematics Hangzhou Normal University

Della Vecchia et al. （see [2]） introduced a kind of modified Bernstein operators which can be used to approximate functions with singularities at endpoints on [0,1]. In the present paper, we obtain a kind of pointwi... 详细信息

关键词： Modified Bernstein operators weighted approximation Stechkin inequality.

Burning magnesium in carbon dioxide for highly effective phosphate removal

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Carbon Energy 2021年第2期3卷 330-337页

作者： Ying Yao Lei Yu meiling wang Alvin Dai Yan Zhang Qiubo Guo Yulin Lin JianguoWen Feng Wu Xiulei Ji Jun Lu School of Materials Science and Engineering Beijing Key Laboratory of Environmental Science and EngineeringBeijing Institute of TechnologyBeijingChina Center for Nanoscale Materials Argonne National LaboratoryLemontIllinois Chemical Sciences and Engineering Division Argonne National LaboratoryLemontIllinois Department of Chemistry Oregon State UniversityCorvallisOregon

Magnesium oxide was found to have high-phosphate-affinity as an effective component to enhance the phosphate removal ability of common adsorbent ***,the currently prepared MgO-based hybrid adsorbents by conventional methods still suffer from the limited low loading of MgO and inferior removal performances,much far away from practical *** this study,an ingenious carbon coated MgO nanocomposite is designed by directly burning magnesium in CO_(2),a well-known textbook reaction.X-ray diffraction analysis,scanning electron microscope and aberration-corrected high-resolution transmission electron microscope demonstrate the sample is well ***,the high content of nanosized MgO combined with defect-rich carbon layer brings unprecedented phosphate removal capacity of 1135.0 mg/g,removal rate of 99% and benign compatibility with coexisting anions and solution ***,the removal mechanism is also investigated in detail by characterizing the sample before and after adsorption.

关键词： carbon dioxide carbon layer magnesium oxide nanocomposite phosphorus removal