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Physiological and Molecular Features of Puccinellia tenuiflora Tolerating Salt and Alkaline-Salt Stress

Journal of Integrative Plant Biology 2013年第3期55卷 262-276页

作者： Xia Zhang Liqin Wei Zizhang Wang tai Wang Key Laboratory of Plant Molecular Physiology Institute of Botanythe Chinese Academy of SciencesNational Center for Plant Gene Research Graduate School of the Chinese Academy of Sciences

Saline-alkali soil seriously threatens agriculture productivity; therefore, understanding the mechanism of plant tolerance to alkaline-salt stress has become a major challenge. halophytic Puccinellia tenuiflora can tolerate salt and alkaline-salt stress, and is thus an ideal plant for studying this tolerance mechanism. In this study, we examined the salt and alkaline-salt stress tolerance of P. tenuiflora, and analyzed gene expression profiles under these stresses. Physiological experiments revealed that P. tenuiflora can grow normally with maximum stress under 600 mmol/L NaCl and 150 mmol/L Na 2 CO 3 （ph 11.0） for 6 d. We identified 4,982 unigenes closely homologous to rice and barley. Furthermore, 1,105 genes showed differentially expressed profiles under salt and alkaline-salt treatments. Differentially expressed genes were overrepresented in functions of photosynthesis, oxidation reduction, signal transduction, and transcription regulation. Almost all genes downregulated under salt and alkaline-salt stress were related to cell structure, photosynthesis, and protein synthesis. Comparing with salt stress, alkaline-salt stress triggered more differentially expressed genes and significantly upregulated genes related to h ＋ transport and citric acid synthesis. These data indicate common and diverse features of salt and alkaline-salt stress tolerance, and give novel insights into the molecular and physiological mechanisms of plant salt and alkaline-salt tolerance.

关键词： Puccinellia tenuiflora halophyte salt and alkaline-salt tolerance microarray assay gene expression profiles.

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Structure,morphology,and microwave dielectric properties of SmAlO_(3) synthesized by stearic acid route

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Journal of Advanced Ceramics 2020年第5期9卷 558-566页

作者： Jiamao LI Chuimin ZhANG hui LIU tai QIU Chuangang FAN School of Materials Science and Engineering Anhui University of TechnologyMaanshan 243032China bKey Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials Ministry of EducationAnhui University of TechnologyMaanshan 243002China College of Materials Science and Engineering Nanjing Tech UniversityNanjing 211816China

A rapid and facile approach was developed for the synthesis of ultrafine SmAlO_(3) powders through the combustion of stearic acid *** obtained products were characterized by typical techniques including X-ray diffraction(XRD),Fourier Transform Infrared(FT-IR),thermogravimetric and differential thermal analysis(TG-DTA),scanning electron microscopy(SEM),and transmission electron microscopy(TEM)to analyze the phase composition and *** dielectric characteristics of SmAlO_(3) microwave ceramics,using the as-obtained products as original materials,were also *** with the conventional solid-state reaction method,the synthesis temperature was dramatically reduced to 750℃.The large-size sheet structure was composed of a number of micro/nano-scale crystallites,which were mostly irregular in shape due to the mutual growth and overlapping shapes of adjacent *** SmAlO_(3) ceramics with high density and uniform microstructure were obtained after sintering at 1500℃ for 4 h due to the favorable sintering activity of the as-synthesized *** addition,desired dielectric properties at microwave frequencies(dielectric constant ε_(r)=20.22,quality factor Q·f=74110 Ghz,and a temperature coefficient of resonant frequency τ_(f)=-74.6 ppm/℃)were achieved.

关键词： stearic acid precursor process nanoparticle perovskite microwave ceramics

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Topological non-hermitian skin effect

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Frontiers of physics 2023年第5期18卷 1-45页

作者： Rijia Lin Tommy tai Linhu Li Ching hua Lee Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing&School of Physics and Astronomy Sun Yat-Sen University(Zhuhai Campus)Zhuhai 519082China Department of Physics Massachusetts Institute of TechnologyCambridgeMA 02139USA Department of Physics National University of SingaporeSingapore117542Singapore

This article reviews recent developments in the non-hermitian skin effect(NhSE),particularly on its rich interplay with *** review starts off with a pedagogical introduction on the modified bulk-boundary correspondence,the synergy and hybridization of NhSE and band topology in higher dimensions,as well as,the associated topology on the complex energy plane such as spectral winding topology and spectral graph *** which,emerging topics are introduced such as non-hermitian criticality,dynamical NhSE phenomena,and the manifestation of NhSE beyond the traditional linear non-interacting crystal lattices,particularly its interplay with quantum many-body ***,we survey the recent demonstrations and experimental proposals of NhSE.

关键词： non-hermitian skin effect topological phases

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Isola in a linear one-degree-of-freedom feedback system with actuator rate saturation

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International Journal of Mechanical System Dynamics 2023年第3期3卷 186-191页

作者： Duc h.Nguyen thomas L.hill Mark h.Lowenberg Faculty of Engineering University of BristolBristolUK

This short communication uses numerical continuation to highlight the existence of an isola in a simple one-degree-of-freedom harmonically forced feedback system with actuator rate limiting as its only nonlinear *** was found that the isola(1)contains only rate-limited responses,(2)merges with the main branch when the forcing amplitude is sufficiently large,and(3)includes stable solutions that create a second attractor in regions where rate limiting is not ***,the isola is composed of two solutions for a given forcing *** solutions have the same amplitudes in the state(pitch rate)projection;however,they have distinct phases,and their amplitudes are also distinct when projected onto the integrator state in the *** rich dynamics observed in such a simple example underlines the impact of rate limiting on feedback ***,the combination of feedback and rate limiting can create detrimental dynamics that is hard to predict and requires careful analysis.

关键词： frequency response harmonic forcing rate saturation isola dynamical system

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Drosophila, destroying angels, and deathcaps! Oh my! A review of mycotoxin tolerance in the genus Drosophila

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Frontiers in Biology 2018年第2期13卷 91-102页

作者： Clare h. Scott Chialvo thomas Werner Department of Biologtcal Sciences University of Alabama Tuscaloosa Alabama USA Department of Biological Sciences Michigan Technological University Houghton Michigan USA

BACKGROUND： Evolutionary novelties, be they morphological or biochemical, fascinate both scientists and non-scientists alike. These types of adaptations can significantly impact the biodiversity of the organisms in which they occur. While much work has been invested in the evolution of novel morphological traits, substantially less is known about the evolution of biochemical adaptations. METhODS： In this review, we present the results of literature searches relating to one such biochemical adaptation： α- amanitin tolerance/resistance in the genus Drosophila. RESULTS： Amatoxins, including α-amanitin, are one of several toxin classes found in Amanita mushrooms. They act by binding to RNA polymerase Ⅱ and inhibiting RNA transcription. Although these toxins are lethal to most eukaryotic organisms, 17 mushroom-feeding Drosophila species are tolerant of natural concentrations of amatoxins and can develop in toxic mushrooms. The use of toxic mushrooms allows these species to avoid infection by parasitic nematodes and lowers competition. Their amatoxin tolerance is not due to mutations that would inhibit α-amanitin from binding to RNA polymerase Ⅱ. Furthermore, the mushroom-feeding flies are able to detoxify the other toxin classes that occur in their mushroom hosts. In addition, resistance has evolved independently in several D. melanogaster strains. Only one of the strains exhibits resistance due to mutations in the target of the toxin. CONCLUSIONS： Given our current understanding of the evolutionary relationships among the mushroom-feeding flies, it appears that amatoxin tolerance evolved multiple times. Furthermore, independent lines of evidence suggest that multiple mechanisms confer α-amanitin tolerance/resistance in Drosophila.

关键词： Drosophila mushroom-feeding biochemical adaptations mushroom toxins cyclopeptides α-amanitin

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Characteristics of general distribution of hepatitis B virus genotypes in China

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hepatobiliary & Pancreatic Diseases International 2009年第4期8卷 397-401页

作者： Zhu, Chang-tai Dong, Chun-Lei Suzhou Univ Changzhou Canc Hosp Dept Lab Med Changzhou 213001 Peoples R China

BACKGROUND: Based on differences in the virus nucleotide sequence, hepatitis B virus (hBV) genotypes are presently divided into genotypes A-h. The geographic distributions of hBV genotypes differ in countries and regions. To determine the general characteristics of their distributions in the mainland of China, we reviewed articles on hBV genotypes published in China. METhODS: The Wanfang Database and the CNKI Database were searched for original articles involving hBV in China, and then the data from the articles were classified according to genotype and latitude and analyzed using SPSS 11.0. RESULTS: The main hBV genotypes were C, B and BC, and their rates were 50.99%, 35.58%, 6.07%, respectively; other genotypes were rare. There was a negative correlation between latitude and the rate of genotype B (r=-0.782, Phile a positive correlation existed between latitude and the rate of genotype C (r=0.646, Phe rates of other genotypes (r=0.294, P>0.05). CONCLUSIONS: In China, hBV genotype C predominates, followed by genotype C and mixed genotype BC; genotypes A, D and others are rare. With an increasing latitude, the distribution of genotype B decreases gradually, while that of genotype C tends to increase. The other genotypes do not show any changes.

关键词： hepatitis B virus genotype chronic hepatitis B

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INCIDENCE MATRIX APPROACh FOR CALCULATING READINESS LEVELS

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Journal of Systems Science and Systems Engineering 2014年第4期23卷 377-403页

作者： Mark A.London thomas h.holzer Timothy J.Eveleigh Shahryar Sarkani School of Engineering and Applied Science George Washington University

Contemporary system maturity assessment approaches have failed to provide robust quantitative system evaluations resulting in increased program costs and developmental *** assessment metrics,such as Technology Readiness Levels（TRL）,do not sufficiently evaluate increasingly complex *** System Readiness Level（SRL）is a newly developed system development metric that is a mathematical function of TRL and Integration Readiness Level（IRL） values for the components and connections of a particular *** acceptance has been hindered because of concerns over SRL mathematical operations that may lead to inaccurate system readiness *** inaccurate system readiness assessments are called readiness reversals.A new SRL calculation method using incidence matrices is proposed to alleviate these mathematical *** presence of SRL readiness reversal is modeled for four SRL calculation methods across several system *** regression analysis demonstrates that the proposed Incidence Matrix SRL（IMSRL）method has a decreased presence of readiness reversal than other approaches suggested in the *** SRL methods will foster greater SRL adoption by systems engineering professionals and will support system development risk reduction goals.

关键词： Technology Readiness Level(TRL) integration readiness level(IRL) system readiness level(SRL) system readiness graph theory systems engineering

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Lophozonia tree cavities used for nesting by Slender-billed Parakeets(Enicognathus leptorhynchus)in the central valley of southern Chile:a potentially vanishing keystone resource

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Chinese Birds 2017年第1期8卷 25-36页

作者： thomas h.White Jr. Jaime E.Jiménez Puerto Rican Parrot Recovery Program United States Fish and Wildlife ServiceBox 1600Rio GrandePR 00745USA Sub-Antarctic Biocultural Conservation Program Department of Biological SciencesUniversity of North TexasDentonTX 76201USA Sub-Antarctic Biocultural Conservation Program Department of Philosophy and ReligionUniversity of North TexasDentonTX 76201USA Omora Etnobotanical Park Universidad de MagallanesPuerto WilliamsChile

Background: The Slender-billed Parakeet(Enicognathus leptorhynchus) is a psittacine endemic to southern Chile and an obligate secondary cavity-nester. In the central valley of southern Chile, most(94%) of the known Slender-billed Parakeet nests have occurred in large, mature southern beech(Lophozonia obliqua) trees(locally known as "pellines"). As relicts of the original old-growth forests of southern Chile, most pellines have been lost due to extensive landclearing throughout the region, potentially threatening long-term persistence of the Slender-billed ***: We conducted our study in the central valley of southern Chile, near the city of Osorno during three consecutive nesting seasons(November–January, 2008–2011). Nest trees used by Slender-billed Parakeets were located by direct observation of parakeet activities and through interviews with local residents, some of whom were former parrot nest poachers. Nest cavities were accessed, inspected and measured using single-rope climbing techniques. We report means, standard errors, 95% confidence intervals and ranges for 11 cavity-related variables. We also report clutch sizes encountered in active nests, and age estimates of nest trees based on known growth rates of Lophozonia trees in southern Chile. Linear regressions were used to evaluate potential relationships between cavity-related variables and clutch ***: We located and measured 38 Lophozonia tree cavities used for nesting by Slender-billed Parakeets. Compared to those used by other psittacines, nest trees were relatively large, averaging 30.4 breast height of 134.5 ter ± 1.1 m in height with a mean diameter at ± 4.7 cm. Based on estimated annual diameincrement, ages of nest trees ranged from approximately 209–485 years. Nest cavities entrances averaged 12.5 ± 0.9 m in height above ground level. Cavity entrance widths averaged 51.0 ± 13.3 cm(vertical) by 11.5 ± 0.7 cm(horizontal). Cavity entrance orientations were apparently random, with

关键词： Conservation Deforestation habitat loss Lophozonia obliqua Pellines Psittacidae Regeneration

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Syntheses,Crystal Structures,and Fluorescence Properties of Three Coordination Polymers Constructed Based on Benzoic Acid and Its Derivatives

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Chinese Journal of Structural Chemistry 2017年第12期36卷 2058-2066页

作者： LIU Guang-Zeng ChEN hong-tai ZhANG Xiu-Tang Advanced Material Institute of Research College of Chemistry and Chemical EngineeringQilu Normal UniversityJinan 250013China

Three new different dimensional coordination polymers, namely, [Zn（BA-）2（4,4？-bib）-1.5]n（1）, [Zn（4-Br BA-）2（1,4-bmb）]n（2） and [Mn（4-Br BA）2（4,4？-bib）]n（3） have been assembled through the mixed-ligand synthetic strategy（4-hBr BA = 4-bromobenzoic acid, hBA = benzoic acid, 1,4-bmb = 1,4-bis（1 h-imidazol-4-yl）benzene, 4,4？-bib = 4,4？-bis（imidazolyl）biphenyl）. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses（EA）, powder X-ray diffraction（PXRD）, and thermogravimetric（TG） analyses. Single-crystal X-ray diffraction analysis reveals that the crystals of complexes 1~3 are all in triclinic systems, space group P1. Complexes 1 and 2 are 0D binuclear structures, and 3 is a 1 D chain. Moreover, the solid state fluorescence properties of 1 and 2 have been investigated.

关键词： 4-bromobenzoic acid benzoic acid 1 4-bis[(1h-imidazol-1-yl)methyl]benzene 4 4΄-bis(imidazolyl)biphenyl

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（3,3）-Connected Three-dimentional Supramolecular Metal Organic Polyhedral Based on Nanometresized Ligand with Magnetism Properties

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Chemical Research in Chinese Universities 2018年第5期34卷 723-726页

作者： ZhOU Xiaojing LIU Lili tai Xishi ZhANG hui College of Chemical & Chemieal Engineering and Enviromental Engineering Weifang University Weifang 261061 P. R. China

A three-dimentinal metal organic framework [Co2（L）CI（DMF）2（h20）]（DMF）3（h20）3 based on the nano- metresized ligand 4,4＇,4＂-[1,3,5-benzenetriyltris（carbonylimino）]trisbenzoic acid was synthesized, and characterized by means of single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy, thermogravimetry analysis and magnetism. This obtained structure can be considered to be constructed from 2D layer, which displays the topology of hbc based on Co2（COO）3 secondary building unit, and further to be linked into a 3D suprarnolecular architecture by N--h...O hydrogen bonds. The magnetism of the complex was carried out, which shows ferromag- netic exchange interactions.

关键词： Co complex C3-Symmetric ligand Ferromagnetic

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