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Two Lycopene β-Cyclases Genes from Sweet Orange (Citrus sinensis L. Osbeck) Encode Enzymes With Different Functional Efficiency During the Conversion of Lycopene-to-Provitamin A

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Journal of Integrative Agriculture 2013年第10期12卷 1731-1747页

作者： ZHANG Jian-cheng ZHOU Wen-jing XU Qiang TAO Neng-guo YE Jun-li guo Fei XU Juan DENG Xiu-xin Key Laboratory of Horticultural Plant Biology Ministry of Education/College of Horticulture and ForestryHuazhong Agricultural University

Citrus fruits are rich in *** the carotenoid biosynthetic pathway,lycopene β-cyclase（LCYb,EC：1.14.-.-） is a key regulatory enzyme in the catalysis of lycopene to β-carotene,an important dietary precursor of vitamin A for human *** closely related lycopene β-cyclase cDnas,designated CsLCYb1 and CsLCYb2,were isolated from the pulp of orange fruits（Citrus sinensis）.The expression level of CsLCYb genes is lower in the flavedo and juice sacs of a lycopeneaccumulating genotype Cara Cara than that in common genotype Washington,and this might be correlated with lycopene accumulation in Cara Cara *** CsLCYb1 efficiently converted lycopene into the bicyclic β-carotene in an Escherichia coli expression system,but the CsLCYb2 exhibited a lower enzyme activity and converted lycopene into the β-carotene and the monocyclic γ-*** tomato transformation studies,expression of CsLCYb1 under the control of the cauliflower mosaic virus（CaMV） 35S constitutive promoter resulted in a virtually complete conversion of lycopene into β-carotene,and the ripe fruits displayed a bright orange ***,the CsLCYb2 transgenic tomato plants did not show an altered fruit colour during development and *** fruits of the CsLCYb1 transgenic plants,most of the lycopene was converted into β-carotene with provitamin A levels reaching about 700 μg ***,most transgenic tomatoes showed a reduction in total carotenoid accumulation,and this is consistent with the decrease in expression of endogenous carotenogenic genes in transgenic ***,these results suggested that the cloned CsLCYb1 and CsLCYb2 genes encoded two functional lycopene β-cyclases with different catalytic efficiency,and they may have potential for metabolite engineering toward altering pigmentation and enhancing nutritional value of food crops.

关键词： carotenoids biosynthesis citrus fruit gene expression lycopene lycopene β-cyclase β-Carotene transgenic tomato fruit

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Bacteria-responsive programmed self-activating antibacterial hydrogel to remodel regeneration microenvironment for infected wound healing

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national Science Review 2024年第4期11卷 254-270页

作者： Yutong Yang Jiaxin Wang Shengfei Huang Meng li Jueying Chen Dandan Pei Zhen Tang Baolin guo State Key Laboratory for Mechanical Behavior of Materials and Frontier Institute of Science and Technology and Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine ResearchCollege of Stomatology Xi'an Jiaotong University Department of Orthopedics Tangdu Hospital Fourth Military Medical University Department of Orthopedics The First Affiliated Hospital of Xi'an Jiaotong University

There is still an urgent need to develop hydrogels with intelligent antibacterial ability to achieve on-demand treatment of infected wounds and accelerate wound healing by improving the regeneration microenvironment. We proposed a strategy of hydrogel wound dressing with bacteria-responsive self-activating antibacterial property and multiple nanozyme activities to remodel the regeneration microenvironment in order to significantly promote infected wound healing. Specifically, p H-responsive H2O2self-supplying composite nanozyme（MSCO） and p H/enzyme-sensitive bacteria-responsive triblock micelles encapsulated with lactate oxidase（PPEL） were prepared and encapsulated in hydrogels composed of L-arginine-modified chitosan（CA） and phenylboronic acid-modified oxidized dextran（ODP） to form a cascade bacteria-responsive self-activating antibacterial composite hydrogel platform. The hydrogels respond to multifactorial changes of the bacterial metabolic microenvironment to achieve on-demand antibacterial and biofilm eradication through transformation of bacterial metabolites, and chemodynamic therapy enhanced by nanozyme activity in conjunction with self-driven nitric oxide（NO） release. The composite hydrogel showed 'self-diagnostic' treatment for changes in the wound *** self-activating antibacterial therapy in the infection stage to self-adaptive oxidative stress relief and angiogenesis in the post-infection stage, it promotes wound closure, accelerates wound collagen deposition and angiogenesis, and completely improves the microenvironment of infected wound regeneration, which provides a new method for the design of intelligent wound dressings.

关键词： bacterial response hydrogel dressing multiple nanozyme activity biofilm elimination infected motion wound healing

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5,7,2',4',5'-Pentamethoxyflavanone regulates M1/M2 macrophage phenotype and protects the septic mice

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Chinese Journal of natural Medicines 2019年第5期17卷 363-371页

作者： FENG li-li XU li-Sha guo Meng-Meng HUANG Wei ZHU Jia-Zhen KONG ling-Dong WU Xu-Dong XU Qiang State Key Laboratory of Pharmaceutical Biotechnology School of Life Sciences Nanjing University

Flavonoids have been reported to exert protective effect against many inflammatory diseases, while the underlying cellular mechanisms are still not completely known. In the present study, we explored the anti-inflammation activity of 5, 7, 2', 4', 5'-pentamethoxyflavanone(abbreviated as Pen.), a kind of polymethoxylated flavonoid, both in vitro and in vivo experiments. Pen. was showed no obvious toxicity in macrophages even at high dosage treatment. Our results indicated that Pen. significantly inhibited both mR na and protein level of proinflammatory cytokines, IL-1β, IL-6, TNF-α and iN OS, which was characteristic expressed on M1 polarized macrophages. These effects of Pen. were further confirmed by diminished expression of CD11c, the M1 macrophage surface marker. Further researches showed that the mechanism was due to that Pen. downregulated the activity of p65, key transcription factor for M1 polarization. On the other hand, Pen. also enhanced M2 polarization with upregulation of anti-inflammatory factors and increase of M2 macrophage surface markers, which lead to the balance of M1 and M2 macrophages. Moreover, in vivo research verified that Pen. treatment alleviated LPS-induced sepsis in mice by increasing survival rate, decreasing inflammatory cytokines and improving lung tissue damage. In summary, our results suggested that Pen. modulated macrophage phenotype via suppressing p65 signal pathway to exert the anti-inflammation activity.

关键词： Macrophage polarization Anti-inflammation NFκB Sepsis 5,7,2',4',5'-Pentamethoxyflavanone(Pen.)

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In situ dynamics response mechanism of the tunable length-diameter ratio nanochains for excellent microwave absorber

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nano Research 2020年第1期13卷 72-78页

作者： Wenbin You Ke Pei liting Yang Xiao li Xiaofeng Shi Xuefeng Yu Huiqiao guo Renchao Che Laboratory of Advanced Materials Department of Materials Science and CollaborativeInnovation Center of Chemistry for Energy Materials(iChem)Fudan University220 Handan RoadShanghai200433China

Faster response benefits the high-performance of magnetic material in various live ***,enhancing response speed toward the applied field via engineering advantages in structures is highly *** this paper,the precise synthesis of Co nanochain with the tunable length-diameter ratio is realized via a magnetic-field-guided assembly *** Co nanochain exhibits enhanced microwave absorption performance(near to-60 dB,layer thickness 2.2 mm)and broader effective absorption bandwidth(over 2/3 of total S,C,X,Ku bands).Furthermore,the simulated dynamic magnetic response reveals that the domain motion in 1D chain is faster than that in 0D nanoparticle,which is the determining factor of magnetic loss ***,based on the controllable magnetic field experiment via in situ transmission electron microscopy,the association between magnetic response and microstructure is first present at the *** real and imaginary parts of relative complex permeability are determined by the domain migration confined inside Co nanochain and the magnetic flux field surrounded outside Co nanochain,***,these findings can be extended to the novel design of microwave absorbers and promising candidates of magnetic carriers based on 1D structure.

关键词： microwave absorption in situ transmission electron microscopy(TEM) magnetic materials cobalt nanochain dynamic response

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Influences of fractional separation on the structure and reactivity of wheat straw cellulose for producing 5-hydroxymethylfurfural

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Chinese Journal of Chemical Engineering 2024年第9期73卷 154-162页

作者： Di Wu Ping Hu Hui li Zhidan Xue Hang Lv Yimeng guo Changwei Hu liangfang Zhu Key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengduSichuan 610064China

High-efficient production of 5-hydroxymethylfurfural(HMF),a“sleeping giant”in sustainable chemistry,from cellulose depends significantly on the effective separation of cellulose from lignocellulosic ***,we report the fractional separation of wheat straw cellulose(WSC)from wheat straw under solvothermal conditions using a mixed solvent of γ-valerolactone(GVL)and H_(2)O as the separating solvent,wherein the impacts of fractional separation parameters(solvent composition,temperature,and time)on removals of lignin and hemicellulose as well as purity and recovery of cellulose were studied by a Box-Behnken Design of response surface *** optimization of the solvothermal parameters enabled an optimal fractional separation condition(V_(GVL):~60.0%,T:205℃,t:~1.7 h)that led to a higher purity(89.4%)and recovery(86.7%)of cellulose in WSC.A further correlation of the removals of lignin and hemicellulose as well as purity and recovery of cellulose with the yield of HMF excluded an independent influence of the above ***,a comprehensive contribution of high fractional separation efficiency(defined as the product of cellulose purity and recovery)and low crystallinity of WSC was found to improve the HMF ***,the heat-and freeze-dryings of WSC after the solvothermal separation were found to lower the HMF molar yield because it re-improved the crystallinity of WSC.A high HMF molar yield of 58.6%was achieved after reacting wet-WSC in a mixed solvent of 1,4-dioxane and H_(2)O at 180℃for 20 min,which was 1.5 fold higher than that from microcrystalline *** work highlights the importance of enhancing the fractional separation efficiency of cellulose from lignocellulosic biomass while avoiding the drying process for future HMF biorefinery.

关键词： Biomass Separation Drying Crystallinity Wheat straw cellulose 5-Hydroxymethylfurfural

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Bypass-Enabled Thread Compaction for Divergent Control Flow in Graphics Processing Units

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Journal of Shanghai Jiaotong university(Science) 2021年第2期26卷 245-256页

作者： li Bingchao WEI Jizeng guo Wei SUN Jizhou College of Computer Science and Technology Civil Aviation University of ChinaTianjin 300300China College of Intelligence and Computing Tianjin UniversityTianjin 300350China

Graphics processing units(GPUs)employ the single instruction multiple data(SIMD)hardware to run threads in parallel and allow each thread to maintain an arbitrary control *** running concurrently within a warp may jump to different paths after conditional *** divergent control flow makes some lanes idle and hence reduces the SIMD utilization of *** alleviate the waste of SIMD lanes,threads from multiple warps can be collected together to improve the SIMD lane utilization by compacting threads into idle ***,this mechanism induces extra barrier synchronizations since warps have to be stalled to wait for other warps for compactions,resulting in that no warps are scheduled in some *** this paper,we propose an approach to reduce the overhead of barrier synchronizat ions induced by compactions,In our approach,a compaction is bypassed by warps whose threads all jump to the same path after ***,warps waiting for a compaction can also bypass this compaction when no warps are ready for *** addition,a compaction is canceled if idle lanes can not be reduced via this *** experimental results demonstrate that our approach provides an average improvement of 21%over the baseline GPU for applications with massive divergent branches,while recovering the performance loss induced by compactions by 13%on average for applications with many non-divergent control flows.

关键词： graphics processing unit(GPU) single instruction ultiple data(SIMD) thread warps bypass

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Diffusion and reaction mechanism of limestone and quartz in fluxed iron ore pellet roasting process

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 485-497页

作者： Yufeng guo Jinlai Zhang Shuai Wang Jianjun Fan Haokun li Feng Chen Kuo liu lingzhi Yang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Technology Center Taiyuan Iron Steel(Group)Co.Ltd.(TISCO)Taiyuan 030003China

The increase to the proportion of fluxed pellets in the blast furnace burden is a useful way to reduce the carbon emissions in the ironmaking *** this study,the interaction between calcium carbonate and iron ore powder and the mineralization mechanism of fluxed iron ore pellet in the roasting process were investigated through diffusion couple *** electron microscopy with energy dispersive spectroscopy was used to study the elements’diffusion and phase transformation during the roasting *** results indicated that limestone decomposed into calcium oxide,and magnetite was oxidized to hematite at the early stage of *** the increase in roasting temperature,the diffusion rate of Fe and Ca was obviously accelerated,while the diffusion rate of Si was relatively *** order of magnitude of interdiffusion coefficient of Fe_(2)O_(3)-CaO diffusion couple was 10^(−10) m^(2)·s^(−1) at a roasting temperature of 1200℃for 9 ***_(2)Fe_(2)O_(5) was the initial product in the Fe_(2)O_(3)-CaO-SiO_(2) diffusion interface,and then Ca_(2)Fe_(2)O_(5) continued to react with Fe_(2)O_(3) to form CaFe_(2)O_(4).With the expansion of the diffusion region,the sillico-ferrite of calcium liquid phase was produced due to the melting of SiO_(2) into CaFe_(2)O_(4),which can strengthen the consolidation of fluxed ***,andradite would be formed around a small part of quartz particles,which is also conducive to the consolidation of fluxed *** addition,the principle diagram of limestone and quartz diffusion reaction in the process of fluxed pellet roasting was discussed.

关键词： fluxed iron ore pellet limestone hematite quartz diffusion reaction

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HAZ Characterization and Mechanical Properties of QP980-DP980 Laser Welded Joints

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Chinese Journal of Mechanical Engineering 2021年第4期34卷 262-275页

作者： Junliang Xue Peng Peng Wei guo Mingsheng Xia Caiwang Tan Zhandong Wan Hongqiang Zhang Yongqiang li School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China R&D Center TANGSTEEL CompanyHBIS GroupTangshan 063016China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology at WeihaiWeihai 264209China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Electrical Engineering Department Changchun Automobile Industry InstituteChangchun 130013China

The QP980-DP980 dissimilar steel joints were fabricated by fiber laser *** weld zone(WZ)was fully martensitic structure,and heat-affected zone(HAZ)contained newly-formed martensite and partially tempered martensite(TM)in both *** supercritical HAZ of the QP980 side had higher microhardness(~549.5 Hv)than that of the WZ due to the finer martensite.A softened zone was present in HAZ of QP980 and DP980,the dropped microhardness of softened zone of the QP980 and DP980 wasΔ21.8 Hv andΔ40.9 Hv,*** walls and slip bands were likely formed at the grain boundaries with the increase of strain,leading to the formation of low angle grain boundaries(LAGBs).Dislocation accumulation more easily occurred in the LAGBs than that of the HAGBs,which led to significant dislocation interaction and formation of *** electron back-scattered diffraction(EBSD)results showed the fraction of LAGBs in sub-critical HAZ of DP980 side was the highest under different deformation conditions during tensile testing,resulting in the failure of joints located at the sub-critical HAZ of DP980 *** QP980-DP980 dissimilar steel joints presented higher elongation(~11.21%)and ultimate tensile strength(~1011.53 MPa)than that of DP980-DP980 similar steel joints,because during the tensile process of the QP980-DP980 dissimilar steel joint(~8.2%and 991.38 MPa),the strain concentration firstly occurred on the excellent QP980 ***,Erichsen cupping tests showed that the dissimilar welded joints had the lowest Erichsen value(~5.92 mm)and the peak punch force(~28.4 kN)due to the presence of large amount of brittle martensite in WZ and inhomogeneous deformation.

关键词： QP980 steel DP980 steel Fiber laser welding Microstructure evolution Tensile properties Formability

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Performance of the Multilayer Film for Infrared Stealth based on VO_(2) Thermochromism

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Journal of Thermal Science 2024年第4期33卷 1312-1324页

作者： li Yaru WANG Fuqiang ZHANG Aoyu FU Zhichang SU Ronghua GAO Tengfei WANG Zhen guo Jicheng ORDOS Institute of Technology Ordos017000China School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China School of New Energy Harbin Institute of Technology at WeihaiWeihai264209China Defense Engineering Institute AMSPLABeijing100850China

With the development of detection and identification technology,infrared stealth is of great value to realize anti-reconnaissance detection of military *** present,infrared stealth materials generally have deficiency,such as complex structure,inconvenient radiation regulation and cumbersome preparation steps,which greatly limit the practical application of infrared stealth *** view of the above deficiency of infrared stealth materials,we proposed a kind of multilayer film for infrared stealth using VO2thermochromism based on the temperature response mechanism of tuna to adjust its color,and through the intelligent reversible radiation regulation mechanism to meet the infrared stealth requirements of tanks in different actual *** results show that when the temperature increases from 300 K to 373 K,the peak emissivity of the film decreases from 94%to 20%in the 8-14μm band after structural optimization,which can realize the infrared stealth of the high temperature target in the 8-14μm *** average emissivity of the multilayer film for infrared stealth at3-5μm and 8-14μm band can be reduced to 34%and 27%at 373 K,and the peak emissivity at 5-8μm band can reach 65%,realizing dual-band infrared stealth in the 3-5μm and 8-14μm bands and heat dissipation in the 5-8μm *** multilayer film for infrared stealth based on VO2thermochromism designed by the authors can meet the characteristics of simple film structure,convenient radiation regulation and simple preparation.

关键词： vanadium dioxide multilayer film infrared stealth thermal management

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Generalization ability of a CNNγ-ray localization model for radiation imaging

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Nuclear Science and Techniques 2023年第12期34卷 53-65页

作者： Wei Lu Hai‑Wei Zhang Ming‑Zhe liu Hao‑Xuan li Xian‑guo Tuo Lei Wang Chengdu University of Technology Chengdu 610059China Sichuan University of Science and Engineering Zigong 643000China

Inγ-ray imaging,localization of theγ-ray interaction in the scintillator is *** neural network(CNN)techniques are highly promising for improvingγ-ray *** study evaluated the generalization capabilities of a CNN localization model with respect to theγ-ray energy and thickness of the *** model maintained a high positional linearity(PL)and spatial resolution for ray energies between 59 and 1460 *** PL at the incident surface of the detector was 0.99,and the resolution of the central incident point source ranged between 0.52 and 1.19 *** modified uniform redundant array(MURA)imaging systems using a thick crystal,the CNNγ-ray localization model significantly improved the useful field-of-view(UFOV)from 60.32 to 93.44%compared to the classical centroid localization ***,the signal-to-noise ratio of the reconstructed images increased from 0.95 to 5.63.

关键词： γ-Ray imaging γ-Ray localization model Convolutional neural network Spatial resolution

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