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Tetraketide α-pyrone reductases in sporopollenin synthesis pathway in Gerbera hybrida:diversification of the minor function

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horticulture Research 2021年第1期8卷 2962-2973页

作者： Lingping Zhu Teng Zhang teemu h.teeri Department of Agricultural Sciences Viikki Plant Science CentreUniversity of Helsinki00014 UH HelsinkiFinland

The structurally robust biopolymer sporopollenin is the major constituent of the exine layer of pollen wall and plays a vital role in plant reproductive *** sporopollenin precursors are synthesized through an ancient polyketide biosynthetic pathway consisting of a series of anther-specific enzymes that are widely present in all land plant ***α-pyrone reductase 1(TKPR1)and TKPR2 are two reductases catalyzing the final reduction of the carbonyl group of the polyketide synthase-synthesized tetraketide intermediates to hydroxylatedα-pyrone compounds,important precursors of *** contrast to the functional conservation of many sporopollenin biosynthesis associated genes confirmed in diverse plant species,TKPR2’s role has been addressed only in Arabidopsis,where it plays a minor role in sporopollenin *** identified in gerbera two non-anther-specific orthologues of AtTKPR2,Gerbera reductase 1(GRED1)and *** dramatically expanded expression pattern implies involvement in pathways outside of the sporopollenin *** this study,we show that GRED1 and GRED2 are still involved in sporopollenin biosynthesis with a similar secondary role as AtTKPR2 in *** further show that this secondary role does not relate to the promoter of the gene,AtTKPR2 cannot rescue pollen development in Arabidopsis even when controlled by the AtTKPR1 *** also identified the gerbera orthologue of AtTKPR1,GTKPR1,and characterized its crucial role in gerbera pollen ***1 is the predominant TKPR in gerbera pollen wall formation,in contrast to the minor roles GRED1 and ***1 is in fact an excellent target for engineering male-sterile gerbera cultivars in horticultural plant breeding.

关键词： synthesis implies outside

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基于旅伴效应的游客就餐行为分析

地球信息科学学报 2024年第2期26卷 408-423页

作者：牟乃夏卞书娣王艳慈张灵先郑允豪 teemu Makkonen 杨腾飞山东科技大学测绘与空间信息学院青岛266590 北京大学遥感与地理信息系统研究所北京100871 东芬兰大学卡累利阿研究所约恩苏FI-801014 中国科学院空天信息创新研究院北京100094

美食已成为游客旅途中乐意分享的热点话题,进一步揭示了游客的旅游行为特征,分析不同旅伴角色下游客就餐行为的差异能更好地理解旅游中的旅伴效应。本文以2012—2020年重庆市美食游记为研究数据,采用社会网络分析等方法研究不同旅伴游... 详细信息

美食已成为游客旅途中乐意分享的热点话题,进一步揭示了游客的旅游行为特征,分析不同旅伴角色下游客就餐行为的差异能更好地理解旅游中的旅伴效应。本文以2012—2020年重庆市美食游记为研究数据,采用社会网络分析等方法研究不同旅伴游客的就餐行为差异,研究表明:(1)游客就餐网络(食物网络和餐厅网络)结构受旅伴影响显著。旅伴的加入有效提升了食物网络节点联系的紧密程度,并扩展了餐厅网络节点关联的空间范围;(2)旅伴角色影响游客在旅程中对特色食物类型的选择。其中,无旅伴的游客(独自一人)在体验特色食物类型时呈现“被动保守型”、旅伴角色为三五好友的游客呈现“遍历型”,而其他旅伴角色的游客呈现“随意/兴趣型”;(3)独自旅行游客和旅伴角色为闺蜜、家庭、情侣以及三五好友游客的就餐行为差异反映了旅伴和社会关系的交叉影响,是美食旅游动机下个体和群体面向多因素综合作用的就餐决策结果。本文从食物类型和餐厅2个视角揭示了不同旅伴角色下的游客就餐行为特征,为深度刻画人群移动行为机理和社会因素影响下的人群活动时空动态提供了科学指导。

关键词：美食旅游游记数据旅伴角色社会网络就餐行为食物类型餐厅重庆

high-performance portable grating-based surface plasmon resonance sensor using a tunable laser at normal incidence

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Photonics Research 2024年第5期12卷 947-958页

作者： DUC LE ANNI RANTA-LASSILA teemu SIPOLA MIKKO KARPPINEN JARNO PETAJA MINNA KEhUSMAA SANNA AIKIO TIAN-LONG GUO MATThIEU ROUSSEY JUSSI hILTUNEN ALEXEY POPOV VTT Technical Research Centre of Finland 90570 OuluFinland Department of Physics and Mathematics University of Eastern FinlandFI-80101 JoensuuFinland

Surface plasmon resonance(SPR)sensors are among the most sensitive *** such devices,a grating is a compelling alternative to a prism for the excitation of a surface plasmon,especially in the development of sensors for point-of-care applications due to their compactness and ***,we demonstrate the use of a tunable laser in a grating-based SPR system for further miniaturization and *** tunable laser working at normal incidence replaces spectral and moving components,while also simplifying the optical *** incidence is conventionally avoided due to the complexity of the control of degenerated SPR *** investigate,both computationally and experimentally,the splitting of the SPR modes at small nonzero incidences,which is lacking in previously reported *** optimizing the grating configuration,we were able to diminish the SPR mode splitting phenomenon when the excitation was feasible with the normal incidence *** fabricated sensor showed a high sensitivity of 1101.6 nm/***,the figure of merit of the sensor,defined as the ratio between the sensitivity and bandwidth of the SPR dip,was *** experimental results were consistent with the simulation *** also demonstrate its capability for detecting low concentrations of glucose and creatinine with the limit of detection of 14.2 and 19.1 mmol/L,respectively.

关键词： tunable splitting excitation

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.M.FEIZABAD M.h.YAS Department of Mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQM)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQM)

holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： h R Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

Recently, reconsidering the Rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~h^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

Novel synthesis of stabilized Bi1-x-yGdxDyyO1.5 solid electrolytes with enhanced conductivity for intermediate temperature solid oxide fuel cells（SOFCs）

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Journal of Rare Earths 2024年第10期42卷 1903-1911页

作者： Ahmed h.Ibrahim Yehia M.Abbas h.A.Ayoub Marwa h.Ali Mustafa Aldoori Materials Science Laboratory Physics DepartmentFaculty of ScienceSuez Canal University Ministry of higher Education and Scientific Research Aliraqia University

herein,we report the synthesis of a Dy-Gd co-doped cubic phase-stabilized Bi2O3solid electrolyte system via solid-state processing under atmospheric *** with Dy3+and Gd3+has been observed to significantly enhance the densification process during sintering for stabilization purposes,thereby improving the electrical properties of δ-Bi2O3-type *** synthesized ceramics were characterized using X-ray diffraction（XRD）,field emission scanning electron microscopy-energy dispersive X-ray spectroscopy（FESEM-EDX）,thermal gravimetry/differential thermal analysis（TG/DTA）,and the four-point probe technique（4PPT）.XRD analysis reveals that the samples Bi1-x-yGdxDyyO1.5（y=0.05/x=0.05,0.10,0,15,and 0.20,and x=0.05/y=0.10,0.15,and 0.20） exhibit a stable face-centered cubic δ-phase and a mixed-phase crystallographic *** XRD analysis of the stabilized δ-phase suggests that the prepared oxides show a face-centered cubic（FCC） structure with a space group of *** micrographs reveal that the composition Bi0.90Gd0.05Dy0.05O1.5has no significant ***,an evident increase in the pore formation is observed as the amount of Gd2O3increases until it reaches 20%.This finding suggests that dense pellets are formed during the sintering process at 900-1000℃.The DTA analyses were performed to verify the phase stability,which agrees with the XRD *** electrochemical performance of the synthesized Dy-Gd co-doped Bi2O3solid electrolyte system was evaluated and analyzed in detail by using the electrochemical impedance spectroscopy（EIS） technique,Based on EIS and conductivity measurements,Bi0.75Gd0.20Dy0.05O1.5exhibits the lowest activation energy of 0.519 eV and the highest conductivity value of 0.398 S/cm at 627℃compared to the other samples;this composition can be used as a solid electrolyte for intermediatetemperature solid oxide fuel cells（SOFCs）.

关键词： Electrochemical impedance spectroscopy (EIS) Fast Fourier transform (FFT) Rare earths Rietveld Solid oxide fuel cells (SOFCs) Solid-state processing

Convexification of hybrid AC-DC Optimal Power Flow with Line-Commutated Converters

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： hongyuan Liang Zhigang Li J.h.Zheng Q.h.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based high-voltage DC (hVDC) systems have been integrated with bulk AC power grids for interregional transmission of renewable power. The nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of hybrid AC-DC power grids. A convexification method for the LCC station model could address such nonconvexity but has rarely been discussed. We devise an equivalent reformulation for classical LCC station models that facilitates second-order cone convex relaxation for the OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with its proof. Equivalence of the proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of the original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

Shell-model representations of the microscopic version of the Bohr-Mottelson collective model

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Communications in Theoretical Physics 2024年第8期76卷 79-90页

作者： h G Ganev Joint Institute for Nuclear Research DubnaRussia Institute of Mechanics Bulgarian Academy of SciencesSofiaBulgaria

The structure of the irreducible collective spaces of the group Sp(12,R),which many-particle nuclear states are classified according to the chain Sp(12,R)⊃U(6)⊃SO(6)⊃SU_(pn)(3)⊗SO(2)⊃SO(3)of the proton-neutron symplectic model(PNSM),is considered in *** chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr-Mottelson collective *** construction of the relevant shell-model representations of the Sp(12,R)group along this chain is considered for three nuclei with varying collective properties and from different mass *** is shown that the SU_(pn)(3)basis states of the Sp(12,R)representations belonging to the SO(6)irreps with seniorityυ≥υ0,withυ0 denoting the maximal seniority SO(6)irrep contained in the Sp(12,R)bandhead,are always Pauli allowed,but organized in a different way into different SO(6)*** is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm *** the SU_(pn)(3)multiplets withinυhe present work are important for the practical application of the microscopic version of the Bohr-Mottelson collective model.

关键词： microscopic shell-model version of the Bohr-Mottelson model proton-neutron symplectic model Sp(12,R)dynamical algebra shell-model representations

Marinoan glaciation in the Indian subcontinent——Anatomy and global implications

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Journal of Palaeogeography 2024年第2期13卷 293-308页

作者： h.N.Bhattacharya Department of Earth Sciences Techno India UniversityWest BengalSector VSalt LakeKolkata700091India

Detailed sedimentological analysis of the Pokaran Boulder Bed,representing the most basal unit of the Neoproterozoic-Lower Cambrian Marwar Supergroup,clearly indicates its glacial *** glacial sediments are interpreted as an ice-contact submarine fan *** on the detrital and inherited zircon population of the Marwar Supergroup sediments and interlayered pyroclastic deposits,a Marinoan cryochron of the Cryogenian Period is envisaged for the Pokaran Boulder *** well-preserved Ediacaran elements in the post-glacial sedimentary succession also support a Cryogenian to Early Cambrian age of the Marwar *** glacial deposition at the base of the Marwar Supergroup strengthens the regional correlation between the studied sediments with the Lesser himalayan Blaini-Krol-Tal sediments and the haqf Supergroup of *** available zircon ages and paleomagnetic data of the Malani Igneous suite,along with the Marinoan glacial deposits,detrital zircon ages,and Ediacaran fossil elements of the Marwar Supergroup add significant information to the Neoproterozoic Earth history.

关键词： Neoproterozoic Marinoan glaciation Diamictites Pokaran Boulder Bed Marwar Supergroup