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社会空间的理论谱系与当代价值

东北师大学报（哲学社会科学版） 2013年第3期 171-175页

作者：张广济计亚萍长春工业大学人文学院吉林长春130012

社会空间理论涵盖的话语场域、经验性事实或想象力,为社会学审视社会世界提供了一种超学科视角和综合性的理论框架。其关于物理空间、精神空间和社会空间的理论区分是对传统的二元辩证法和非此即彼的认识论局限的重大突破。"空间的生产"... 详细信息

社会空间理论涵盖的话语场域、经验性事实或想象力,为社会学审视社会世界提供了一种超学科视角和综合性的理论框架。其关于物理空间、精神空间和社会空间的理论区分是对传统的二元辩证法和非此即彼的认识论局限的重大突破。"空间的生产"、"空间正义"和"权力空间观"的提出,对我们今天思考和解决城乡之间、地区之间发展的不平衡问题,居住分异与社会隔离问题,社会福利与公共服务均等化问题,快速城市化进程中的社会融合问题等都具有重要启发意义。

关键词：社会空间理论谱系当代价值

Dynamic foraging strategy adaptation to heterogeneous environments contributes to social aggregation in snub-nosed monkeys

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Zoological Research 2024年第1期45卷 39-54页

作者： Lan Zhao Sheng-Nan ji Xiao-Bing Du jia-Hui Liu Bo-Lun zhang Pei-Hua Li Yi-Jun Yang Bao-Guo Li Yan-Qing Guo Xiao-guang Qi College of Life Sciences Northwest UniversityXi’anShaanxi 710069China Chengdu Institute of Biology Chinese Academy of SciencesChengduSichuan 610041China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

The dynamics of animal social structures are heavily influenced by environmental patterns of competition and *** folivorous colobine primates,prevailing theories suggest that larger group sizes should be favored in rainforests with a year-round abundance of food,thereby reducing feeding ***,paradoxically,larger groups are frequently found in high-altitude or high-latitude montane ecosystems characterized by a seasonal scarcity of *** contradiction is posited to arise from cooperative benefits in heterogeneous *** investigate this hypothesis,we carried out a six-year field study on two neighboring groups of golden snub-nosed monkey(Rhinopithecus roxellana),a species representing the northernmost distribution of colobine *** showed that the groups adjusted their movement and habitat selection in response to fluctuating climates and spatiotemporal variability of resources,indicative of a dynamic foraging ***,during the cold,resource-scarce conditions in winter,the large group occupied food-rich habitats but did not exhibit significantly longer daily travel distances than the smaller neighboring ***,we compiled an eco-behavioral dataset of 52 colobine species to explore their evolutionary *** of this dataset suggested that the increase in group size may have evolved via home range expansion in response to the cold and heterogeneous climates found at higher altitudes or ***,we developed a multi-benefits framework to interpret the formation of larger groups by integrating environmental *** cold and diverse environments,even smaller groups require larger home ranges to meet their dynamic survival *** spatiotemporal distribution of high-quality resources within these expanded home ranges facilitates more frequent interactions between groups,thereby encouraging social aggregation into larger *** process enhances the benefits of collabor

关键词： Social evolution Folivore paradox MLS Rhinopithecus roxellana Multi-benefits framework

Robust Correlation Clustering Problem with Locally Bounded Disagreements

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Tsinghua Science and Technology 2024年第1期29卷 66-75页

作者： Sai ji Min Li Mei Liang Zhenning zhang Institute of Mathematics Hebei University of TechnologyTianjin 300401China School of Mathematics and Statistics Shandong Normal UniversityJinan 250358China College of Statistics and Data Science Beijing University of TechnologyBeijing 100124China Department of Operations Research and Information Engineering Beijing University of TechnologyBeijing 100124China

Min-max disagreements are an important generalization of the correlation clustering problem(CorCP).It can be defined as *** a marked complete graph G=(V,E),each edge in the graph is marked by a positive label"+"or a negative label"_"based on the similarity of the connected *** goal is to find a clustering C of vertices V,so as to minimize the number of disagreements at the vertex with the most ***,the disagreements are the positive cut edges and the negative non-cut edges produced by clustering *** paper considers two robust min-max disagreements:min-max disagreements with outliers and min-max disagreements with *** parameter δ∈(0,1/14),we first provide a threshold-based iterative clustering algorithm based on LP-rounding technique,which is a(1/δ,7/(1-14δ))-bi-criteria approximation algorithm for both the min-max disagreements with outliers and the min-max disagreements with outliers on one-sided complete bipartite ***,we verify that the above algorithm can achieve an approximation ratio of 21 for min-max disagreements with penalties when we set parameter δ=1/21.

关键词： min-max disagreements outliers penalties approximation algorithm LP-rounding

Contact Stress Reliability Analysis Model for Cylindrical Gear with Circular Arc Tooth Trace Based on an Improved Metamodel

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 593-619页

作者： Qi zhang Zhixin Chen Yang Wu Guoqi Xiang guang Wen Xuegang zhang Yongchun Xie guangchun Yang School of Intelligent Manufacturing&Automobile Chengdu Industrial Vocational Technical CollegeChengdu610218China School of Intelligent Manufacturing Panzhihua UniversityPanzhihua617000China School of Electrical Engineering Chengdu Industry and Trade CollegeChengdu601165China School of Mechanical Engineering Sichuan UniversityChengdu601165China Chengdu Technological University Chengdu611730China

Although there is currently no unified standard theoretical formula for calculating the contact stress of cylindrical gears with a circular arc tooth trace(referred to as CATT gear),a mathematical model for determining the contact stress of CATT gear is essential for studying how parameters affect its contact stress and building the contact stress limit state equation for contact stress reliability *** this study,a mathematical relationship between design parameters and contact stress is formulated using the *** enhance the model’s accuracy,we propose a new hybrid algorithm that merges the genetic algorithm with the Quantum Particle Swarm optimization algorithm,leveraging the strengths of ***,the“parental inheritance+self-learning”optimization model is used to fine-tune the KrigingMetamodel’s *** this,amathematicalmodel for calculating the contact stress of Variable Hyperbolic Circular-Arc-Tooth-Trace(VH-CATT)gears using the optimized Kriging model was *** then examined how different gear parameters affect the VH-CATT gears’contact *** simulation results show:(1)Improvements in R2,RMSE,and RMAE.R2 rose from0.9852 to 0.9974(a 1.22%increase),nearing 1,suggesting the optimized Kriging Metamodel’s global error is ***,RMSE dropped from3.9210 to 1.6492,a decline of 57.94%.The global error of the GA-IQPSO-Kriging algorithm was also reduced,with RMAE decreasing by 58.69%from 0.1823 to 0.0753,showing the algorithm’s enhanced *** a comparison of ten experimental groups selected randomly,the GA-IQPSO-Kriging and FEM-based contact analysis methods were used to measure contact *** revealed a maximum error of 12.11667 MPA,which represents 2.85%of the real value.(2)Several factors,including the pressure angle,tooth width,modulus,and tooth line radius,are inversely related to contact *** descending order of their impact on the contact stress is:tooth line radius>modulus

关键词： CATT gear contact stress finite element method metamodel hybrid algorithm influencing factors

ChMYB1-ChbHLH42-ChTTG1 module regulates abscisic acidinduced anthocyanin biosynthesis in Cerasus humilis

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Horticultural Plant Journal 2024年第1期10卷 51-65页

作者： Xiaolong ji Zhe Li Mingyu zhang Shaoyu Lang Xingshun Song State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbinHeilongjiang 150040China Department of Genetics College of Life ScienceNortheast Forestry UniversityHarbinHeilongjiang 150040China

Cerasus humilis is a kind of economic fruit tree peculiar to China,which is widely used in the food,landscape,and pharmaceutical *** are a phenolic metabolite that plays an essential role in fruit ***,the regulatory network of *** in anthocyanin biosynthesis is still *** this study,the R2R3-MYB transcription factor ChMYB1 was isolated from the full genome of the *** one-hybrid,dual-luciferase assays,and GUS staining showed that ChMYB1 significantly increased anthocyanin contents in *** fruit by promoting the expression of ChCHS and ChUFGT by binding MBS(MYB-binding elements).ChMYB1 interacted with ChbHLH42and ChTTG1 to form the MBW complex and further enhanced the expression of *** addition,abscisic acid(ABA)treatment promoted the expression of ChMYB1 and anthocyanin accumulation in *** ***,ABA treatment enhanced the interaction between ChMYB1 and ***,ChABI5 inhibited the interaction between ChMYB1 and *** data elucidated the primary molecular mechanism of anthocyanin biosynthesis in *** fruit,deepening the understanding of the regulatory network affecting anthocyanin metabolism in edible fruit crops.

关键词： Cerasus humilis Anthocyanin ChMYB1 Fruit ABA

Lift-Off Effect of Koch and Circular Differential Pickup Eddy Current Probes

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 283-293页

作者： Guolong Chen Zheng Cao Shuaishuai zhang ji Wei Wei Gao Wuyin jin School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050China

A flexible or planar eddy current probe with a differential structure can suppress the lift-off noise during the inspection of ***,the extent of the lift-off effect on differential probes,including different coil structures,*** this study,two planar eddy current probes with differential pickup structures and the same size,Koch and circular probes,were used to compare lift-off *** eddy current distributions of the probes perturbed by 0°and 90°cracks were obtained by finite element *** analysis results show that the 90°crack can impede the eddy current induced by the Koch probe even further at relatively low lift-off *** peak-to-peak values of the signal output from the two probes were compared at different lift-off distances using finite element analysis and experimental *** addition,the effects of different frequencies on the lift-off were studied *** results show that the signal peak-to-peak value of the Koch probe for the inspection of cracks in 90°orientation is larger than that of the circular probe when the lift-off distance is smaller than 1.2 *** addition,the influence of the lift-off distance on the peak-to-peak signal value of the two probes was studied via *** indicates that the influence becomes more evident with an increase in excitation *** research discloses the lift-off effect of differential planar eddy current probes with different coil shapes and proves the detection merit of the Koch probe for 90°cracks at low lift-off distances.

关键词： Eddy current testing Differential pickup probe Fractal Koch curve Flexible eddy current probe

Spherical Polyelectrolyte Brush Nanoreactor:Preparation of Hollow TiO_(2) Nanospheres and Characterization by Small Angle X-Ray Scattering

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Chinese Journal of Polymer Science 2024年第9期42卷 1393-1400,I0009页

作者： Yu-Hua zhang Zi-Yu zhang Xin Liu En-guang Ma jiang-Tao Guo Li Li Xu-Hong Guo State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai200237China Shandong Provincial Key Laboratory of Monocrystalline Silicon Semiconductor Materials and Technology College of Chemistry and Chemical EngineeringDezhou UniversityDezhou253023China Institute of Bast Fiber Crops&Center of Southern Economic Crops Chinese Academy of Agricultural SciencesChangsha410205China

Titanium dioxide(TiO_(2))hollow nanoparticles present significant potential for photocatalytic applications while their straightforward preparation with precise structure control is still *** work reports the approach to preparing tunable hollow TiO_(2) nanospheres by utilization of spherical polyelectrolyte brushes(SPB)as nanoreactors and *** the preparation,the evolution of the structure was characterized by small angle X-ray scattering(SAXS),and in combination with dynamic light scattering and transmission electron *** formation of TiO_(2) shell within the brush(SPB@TiO_(2))is confirmed by the significant increase of the electron density,and its internal structure has been analyzed by fitting SAXS data,which can be influenced by Titanium precursors and ammonia *** calcining SPB@TiO_(2) in a muffle furnace,hollow TiO_(2) nanospheres are produced,and their transition to the anatase crystal form is triggered,as confirmed by X-ray diffraction *** the advantages of their hollow structure,these TiO_(2) nanospheres exhibit exceptional catalytic degradation efficiency of methylene blue(MB),tetracycline(TC),and 2,4-dichlorophenoxyacetic acid(2,4-D),and also demonstrate excellent recyclability.

关键词： Spherical polyelectrolyte brush Nanoreactor Hollow titanium dioxide X-ray scattering

Gene cloning,protein expression,and enzymatic characterization of a double-stranded RNA degrading enzyme in Apolygus lucorum

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Insect Science 2024年第1期31卷 119-133页

作者： jie-Yu zhang jing Zhao Keyan Zhu-Salzman Qin-Qin ji Yi-Ping jiang Liu-Bin Xiao De-jin Xu guang-Chun Xu Lin-Quan Ge Yong-An Tan College of Plant Protection Yangzhou UniversityYangzhouJiangsu ProvinceChina Institute of Plant Protection Jiangsu Academy of Agricultural SciencesNanjingJiangsu ProvinceChina Department of Entomology Texas A&M UniversityCollege StationTXUSA Taizhou Customs of the People's Republic of China TaizhouJiangsu ProvinceChina

RNA interference(RNAi)is a powerful tool that post-transcriptionally silences target genes in eukaryotic ***,silencing efficacy varies greatly among different insect ***,we met with little success when attempting to knock down genes in the mirid bug Apolygus lucorum via dsRNA *** disappearance of double-stranded RNA(dsRNA)could be a potential factor that restricts RNAi ***,we found that dsRNA can be degraded in midgut fluids,and a dsRNase of ***(AldsRNase)was identified and *** alignment indicated that its 6 key amino acid residues and the Mg2+-binding site were similar to those of other insects’*** signal peptide and endonuclease non-specific domain shared high sequence identity with the brown-winged green stinkbug Plautia stali *** showed high salivary gland and midgut expression and was continuously expressed through the whole life cycle,with peaks at the 4th instar ecdysis in the whole *** purified AldsRNase protein obtained by heterologously expressed can rapidly degrade *** comparing the substrate specificity of AldsRNase,3 specific substrates(dsRNA,small interfering RNA,and dsDNA)were all degraded,and the most efficient degradation is ***,immunofluorescence revealed that AldsRNase was expressed in the cytoplasm of midgut *** cloning and functional study of AldsRNase,the enzyme activity and substrate specificity of the recombinant protein,as well as the subcellular localization of nuclease,the reason for the disappearance of dsRNA was explained,which was useful in improving RNAi efficiency in *** and related species.

关键词： Apolygus lucorum cloning dsRNase enzymatic activity protein expression

Experimental and numerical investigation of the impacts of rotor tip-rake on excitation forces of pump-jet propulsors

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Journal of Hydrodynamics 2024年第1期36卷 142-157页

作者： Xue-qin ji Xiao-song zhang Chen-jun Yang Xiao-qian Dong State Key Laboratory of Ocean Engineering Marine Numerical Experiment CentreSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China CSSC Shanghai Marine Energy Saving Technology Co. Ltd.Shanghai200011China China Ship Scientific Research Center Shanghai Branch Shanghai200011China

The tip-clearance flow in a pump-jet propulsor exerts great impacts on the fluctuating pressures and resultant unsteady forces,which are important sources of structural vibrations and radiated noise *** blade geometry close to the tip is an important factor determining the vortex strength in the tip-clearance *** the open-water condition,the effects of raking the rotor tips on the duct-surface fluctuating pressures and the resultant unsteady forces acting on different components of the propulsor are investigated via physical model experiments and the numerical solution of Reynolds-averaged Navier-Stokes(RANS)equations coupled with the SST k-ωturbulence *** measured and simulated results of hydrodynamic pressures are consistent to each other,and the simulated flows help better understand why the fluctuating pressures change with the tip *** strong fluctuations of duct-surface pressures are caused by intensive tip separation *** duct-surface pressure fluctuations are effectively reduced by using the rake distribution near the tip towards blade back side and,for the combination of the five-bladed rotor and the seven-bladed stator,the resultant unsteady horizontal(and vertical)forces acting on the duct and stator are also reduced;while increasing rake leads to negative effect on pressure fluctuations and unsteady horizontal(and vertical)forces acting on all the components of the propulsor.

关键词： Pump-jet tip-clearance tip-rake fluctuating pressures excitation forces