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A Mathematical Model of the Photosynthetic carbon Metabolism Has Multiple Steady States Under the Same Parameter conditions

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Acta Mathematicae Applicatae Sinica 2016年第3期32卷 591-604页

作者： Jin-ling ZHOU Zuo-huan ZHENG Xin-guang ZHU Institute of Science and technology Zhejiang International Studies University. Hangzhou 310012 China Institute of applied Mathematics Academy of Mathematics and Systems Sciences Chinese Academy of Sciences. Beijing 100080 China cAS-MPG Partner Institute for computational Biology and key Laboratory for computational Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China

This paper analyzes a mathematical model of the photosynthetic carbon metabolism, which incorporates not only the calvin-Benson cycle, but also another two important metabolic pathways： starch synthesis and photorespiratory pathway. Theoretically, the paper shows the existence of steady states, stability and instability of the steady states, the effects of cO2 concentration on steady states. Especially, a critical point is found, the system has only one steady state with c02 concentration in the left neighborhood of the critical point, but has two with c02 concentration in the right neighborhood. In addition, the paper also explores the influence of c02 concentration on the efficiency of photosynthesis. These theoretical results not only provide insight to the kinetic behaviors of the photosynthetic carbon metabolism, but also can be used to help improving the efficiency of photosynthesis in plants.

关键词： photosynthesis the efficiency of photosynthesis multiple steady states stability critical point

In situ Synthesis of Ultrasmall Au clusters on Thiol-modified ceO_(2) with Enhanced Stability and cO Oxidation Activity

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chemical Research in chinese Universities 2023年第6期39卷 921-927页

作者： LI Lingling XU Jinhui LIANG Xi WU Xueting WANG Xiao SONG Shuyan ZHANG Hongjie State key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China School of applied chemistry and Engineering University of Science and Technology of ChinaHefei 230026P.R.China Department of chemistry Tsinghua UniversityBeijing 100084P.R.

Gold(Au)nanoclusters supported on various supports have been widely used in the fields of energy and ***,the poor thermal stability of Au nanoclusters on the support interface usually leads to a reduction or even loss of catalytic ***,we used an in situ reduction method to synthesize Au nanoclusters on ceria(ceO_(2))*** this method,sulfhydryl groups were used to modify ceO_(2) nanospheres first,and then Au clusters with an average diameter of 1.5 nm were grown on the surface of ceria reduced with sodium *** presence of the Au-S-ce structure enhances the electron transfer efficiency,making the material exhibit high cO oxidation activity at room ***,due to the strong binding energy of S and Au,the material exhibits a high stability for long time running *** strategy provides an idea for designing stable and active supported ultrasmall Au nanoclusters catalytic materials.

关键词： Au cluster Sulfhydryl Oxygen activation In situ synthesis

Degree-Based Entropy Descriptors of Graphenylene Using Topological Indices

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computer Modeling in Engineering & sciences 2023年第10期137卷 939-964页

作者： M.c.Shanmukha Sokjoon Lee A.Usha k.c.Shilpa Muhammad Azeem Department of Mathematics Bapuji Institute of Engineering&TechnologyDavanagere577004India Department of computer Engineering(Smart Security) Gachon UniversitySeongnam13120South Korea Department of Mathematics Alliance School of Applied MathematicsAlliance UniversityBangalore562106India Department of computer Science and Engineering Bapuji Institute of Engineering&TechnologyDavanagere577004India Department of Mathematics Riphah Institute of Computing and Applied SciencesRiphah International UniversityLahore54660Pakistan

Graph theory plays a significant role in the applications of chemistry,pharmacy,communication,maps,and aeronautical *** molecules of chemical compounds are modelled as a graph to study the properties of the *** geometric structure of the compound relates to a few physical properties such as boiling point,enthalpy,π-electron energy,andmolecular *** article aims to determine the practical application of graph theory by solving one of the interdisciplinary problems describing the structures of benzenoid hydrocarbons and *** topological index is an invariant of a molecular graph associated with the chemical structure,which shows the correlation of chemical structures using many physical,chemical properties and biological *** study aims to introduce some novel degree-based entropy descriptors such as ENTSO,ENTGH,ENTHG,ENTSS,ENTNSO,ENTNReZ1,ENTNReZ2 and ENTNSS using the respective topological ***,the above-mentioned entropy measures and physico-chemical properties of benzenoid hydrocarbons are fitted using linear regression models and calculated for graphenylene structure.

关键词： Topological descriptors weighted entropy graphenylene

The appearance of cytoplasmic cytochrome c precedes apoptosis during Drosophila salivary gland degradation

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Insect Science 2024年第1期31卷 157-172页

作者： Shihui Long Wenxin cao Yongyu Qiu Ruohan Deng Jiali Liu Lidan Zhang Renke Dong Fengxin Liu Sheng Li Haigang Zhao Na Li kang Li Guangdong Provincial key Laboratory of Insect Developmental Biology and applied technology Institute of Insect Science and TechnologySchool of Life SciencesSouth China Normal UniversityGuangzhouChina Guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural UniversityGuangzhouChina Guangmeiyuan R&D center Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied TechnologySouth China Normal UniversityMeizhouGuangdong ProvinceChina School of Food Science and Engineering South China University of TechnologyGuangzhouChina chemPartner PharmaTech co. LtdJiangmenGuangdong ProvinceChina

Apoptosis is an important process for organism development that functions to eliminate cell damage,maintain homeostasis,and remove obsolete tissues during *** mammals,apoptosis is accompanied by the release of cytochrome c(cyt-c)from mitochondria to the ***,whether this process is conserved in the fruit fly,Drosophila melanogaster,remains *** this study,we discovered that during the degradation of Drosophila salivary gland,the transcription of mitochondria apoptosis factors(MAPFs),cyt-c,and death-associated APAF1-related killer(Dark)encoding genes are all upregulated antecedent to initiator and effector caspases encoding *** proteins cyt-c and the active caspase 3 appear gradually in the cytoplasm during salivary gland ***,the cyt-c protein colocates with mito-GFP,the marker indicating cytoplasmic mitochondria,and the change in mitochondrial membrane potential coincides with the appearance of cyt-c in the ***,impeding or promoting 20E-induced transcription factor E93 suppresses or enhances the staining of cyt-c and the active caspase 3 in the cytoplasm of salivary gland,and accordingly decreases or increases the mitochondrial membrane potential,*** research provides evidence that cytoplasmic cyt-c appears before apoptosis during Drosophila salivary gland degradation,shedding light on partial conserved mechanism in apoptosis between insects and mammals.

关键词： active caspase 3 apoptosis cyt-c Drosophila salivary gland

Plant coexistence can enhance phytoextraction of cadmium by tobacco (Nicotiana tabacum L.) in contaminated soil

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Journal of Environmental sciences 2011年第3期23卷 453-460页

作者： Ling Liu Yuefang Li Jianjun Tang Liangliang Hu Xin chen college of Life sciences Zhejiang University Hangzhou 310058 China college of Agriculture Henan University of Science and Technology Luoyang 471003 China

A mesocosm experiment was conducted to investigate whether plant coexistence affects cadmium （cd） uptake by plant in contaminated soil. Tobacco （Nicotiana tabacum L. var. k326） and Japanese clover （kummerowia striata （Thunb.） Schindl.） were used. cadmium was applied as ***2O in solution at three levels （0, 1, and 3 mg/kg soil） to simulate an unpolluted soil and soils that were slightly and moderately polluted with cd. Tobacco （crop）, Japanese clover （non-crop）, and their combination were grown under each cd treatment. compared to monoculture and under all cd treatments, co-planting with Japanese clover did not affect tobacco biomass but significantly increased cd concentration in all tobacco tissues and enhanced cd accumulation in tobacco shoots and roots. compared to monoculture, co-planting reduced soil pH and increased cd bioavailability. For tobacco, co-planting with Japanese clover increased the cd bioconcentration factor （BcF） in cd contaminated soil. Japanese clover also accumulated substantial quantities of cd in shoots and roots. Thus, total cd uptake by the plants was much greater with co-planting than with monoculture. The results suggested that phytoextraction can be effectively increased through tobacco co-planting with Japanese clover in mildly cd-contaminated soil.

关键词： plant coexistence phytoextraction cadmium tobacco Japanese clover

Superconductivity of bilayer titanium/indium thin film grown on SiO2/Si(001)

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chinese Physics B 2018年第6期27卷 429-433页

作者： Zhao-Hong Mo chao Lu Yi Liu Wei Feng Yun Zhang Wen Zhang Shi-Yong Tan Hong-Jun Zhang chun-Yu Guo Xiao-Dong Wang Liang Wang Rui-Zhu Yang Zhong-Guo Ren Xie-Gang Zhu Zhong-Hua Xiong Qi An Xin-chun Lai Institute of Materials China Academy of Engineering PhysicsJiangyou 621908China Department of Engineering and applied Physics School of Physical SciencesUniversity of Science and Technology of ChinaHefei 230026China Zhejiang university Hangzhou 310058China china Academy of Engineering Physics Mianyang 621000China

Bilayer superconducting films with tunable transition temperature（Tc） are a critical ingredient to the fabrication of high-performance transition edge sensors. commonly chosen materials include Mo/Au, Mo/cu, Ti/Au, and Ti/Al systems. Here in this work, titanium/indium（Ti/In） bilayer superconducting films are successfully fabricated on SiO2/Si（001）substrates by molecular beam epitaxy（MBE）. The success in the epitaxial growth of indium on titanium is achieved by lowering the substrate temperature to-150？c during indium evaporation. We measure the critical temperature under a bias current of 10 μA, and obtain different superconducting transition temperatures ranging from 645 m k to 2.7 k by adjusting the thickness ratio of Ti/In. Our results demonstrate that the transition temperature decreases as the thickness ratio of Ti/In increases.

关键词： titanium/indium thin film molecular beam epitaxy (MBE) proximity effect

X-ray absorption investigation of the site occupancies of the copper element in nominal cu_(3)Zn(OH)_(6)FBr

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chinese Physics B 2021年第4期30卷 389-393页

作者： Ruitang Wang Xiaoting Li Xin Han Jiaqi Lin Yong Wang Tian Qian Hong Ding Youguo Shi Xuerong Liu Beijing National Laboratory for condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China university of chinese Academy of sciences Beijing 100049China School of Physical Science and technology ShanghaiTech UniversityShanghai 201210China Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201800China Songshan Lake Materials Laboratory Dongguan 250100China

With Zn substitution to the three-dimensional antiferromagnetically ordered barlowite cu_(4)(OH)_(6)FBr,cu_(3)Zn(OH)_(6)FBr shows no magnetic phase transition down to 50 mk,and the system is suggested to be a two-dimensional kagomé quantum spin liquid[***.34077502(2017)].A key issue to identify such phase diagram is the exact chemical formula of the substituted *** cu L-edge x-ray absorption spectrum(XAS)combined with the MultiX XAS calculations,we evaluate the cu concentration in a nominal cu_(3)Zn(OH)_(6)FBr *** results show that although the cu concentration is 2.80,close to the expected value,there is 34%residual cu occupation in intersite layers between kagomé *** the Zn substitution of the intersite layers is not complete,and likely it intrudes the kagomé layers.

关键词： x-ray absorption spectrum barlowite spin liquid candidate chemical occupations

Expression and localization of vitellogenin genes(VTG)and receptor(VGR)in the gonad development of silver pomfret Pampus argenteus

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Journal of Oceanology and Limnology 2023年第4期41卷 1575-1592页

作者： Zitao XIONG Jiazhe YANG Shun ZHANG Yajun WANG Shanliang XU chunyang GUO Danli WANG School of Marine sciences Ningbo UniversityNingbo 315211China key Laboratory of applied Marine Biotechnology Ningbo UniversityChinese Ministry of EducationNingbo 315211China

Vitellogenesis is the main event of oocyte growth in oviparous animals,which is mainly manifested by the accumulation of vitellogenin(VTG).The accumulation of vitellogenin depends mainly on the absorption of exogenous vitellogenin,which enters oocyte through endocytosis mediated by its receptor(VGR).We investigated the expression and localization of VTG and VGR during gonad development of Pampus *** qPcR results show that vtgs were not expressed in male fish,but in the ovary and liver of female fish;the expression levels went up at first and then *** expression levels of vgr in the testis were low and only 1%-3%of that in *** results show that during the ovarian development of ***,VTG in liver,serum,and ovary all showed a trend from increasing to ***,VTG in liver peaked in StageⅣ,and in serum and ovary peaked in Stage V,reflecting changes in the characteristics of VTG in the liver(synthesis),blood(transport),and ovaries(accumulation).During gonad development,VGR in the ovaries first increased and then decreased,reaching a peak in Stage V,in contrast to vgr mRNA *** VGR content in the testis was extremely low and stable,consistent with vgr *** results show that the location and intensity of VTG and VGR positive signals were synchronized with the changes of their protein content,which revealed that VTG was mainly synthesized in the liver cytoplasm,secreted into the blood,and transported to ovary in StageⅢ.VGR is highly expressed in oocytes in StageⅡ.In StageⅢ,a large amount of VTG reaches the ovary,when VGR begins to translate and is subsequently transported to the plasma membrane of the ***,the positive signal of VGR was stronger near the plasma membrane of oocytes in StagesⅠandⅡ.By using qPcR,ELISA,and immunohistochemistry,the synthesis,transport,and accumulation of vitellogenin were elucidated and the mechanism of its endocytosis on egg membrane mediated by VTG during the de

关键词： Pampus argenteus vitellogenin(VTG) vitellogenin receptor(VGR) vitellogenesis

Segmentation of Brain Tumor Magnetic Resonance Images Using a Teaching-Learning Optimization Algorithm

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computers, Materials & continua 2021年第9期68卷 4191-4203页

作者： J.Jayanthi M.kavitha T.Jayasankar A.Sagai Francis Britto N.B.Prakash Mohamed Yacin Sikkandar c.Bharathiraja Department of computer Science and Engineering Sona College of TechnologySalem636005TamilnaduIndia Department of Electronics and communication Engineering K.Ramakrishnan College of TechnologyTrichy621112India Department of Electronics and communication Engineering University College of EngineeringAnna UniversityTiruchirappalli620024India Department of Mechanical Engineering Rohini College of Engineering and TechnologyPalkulam629401India Department of Electrical and Electronics Engineering National Engineering CollegeKovilpatti628503India Department of Medical Equipment technology College of Applied Medical SciencesMajmaah UniversityAlMajmaah11952Kingdom of Saudi Arabia Department of Electrical and Electronics Engineering SRM Institute of Science and TechnologyChennai603203India

Image recognition is considered to be the pre-eminent paradigm for the automatic detection of tumor diseases in this *** various cancers identified so far,glioma,a type of brain tumor,is one of the deadliest cancers,and it remains challenging to the medicinal *** only consoling factor is that the survival rate of the patient is increased by remarkable percentage with the early diagnosis of the *** diagnosis is attempted to be accomplished with the changes observed in the images of suspected parts of the brain captured in specific interval of *** the captured image,the affected part of the brain is analyzed using magnetic resonance imaging(MRI)*** of different modalities in the captured MRI image demands the best automated model for the easy identification of malignant *** of image processing techniques are available for processing the images to identify the affected *** study concentrates and proposes to improve early diagnosis of glioma using a preprocessing boosted teaching and learning optimization(P-BTLBO)algorithm that automatically segments a brain tumor in an given MRI *** involves contrast enhancement and skull stripping procedures through contrast limited adaptive histogram equalization *** traditional TLBO algorithm that works with the perspective of teacher and the student is here improved by using a boosting *** results obtained using this P-BTLBO algorithm is compared on different benchmark images for the validation of its *** experimental findings show that P-BTLBO algorithm approach outperforms other existing algorithms of its kind.

关键词： Brain tumor TLBO algorithm skull stripping preprocessing segmentation