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Insect Science 2009年第3期16卷 277-285页

作者： Yu Cheng Zhu quentin q. fang USDA-ARS-JWDSRC Stoneville MS 38776 Department of Biology Georgia Southern University Statesboro GA 30460 USA

Several species of Aphelinus have been introduced to the US from the Old World for biological control of the Russian wheat aphid, Diuraphis noxia （Modvilko）. Reproductive incompatibility has been observed among populations collected from different geographic areas. We examined whether or not the reproductive incompatibility between strains of A. asychis was caused by distant phylogenetic relationships. Ribosomal DNA seq.ences of internal transcribed spacers 2 （ITS2） were analyzed in several species of Aphelinus collected from multiple sites of Europe and Asia. Yhe phylogenetic analysis showed that strains within the species A. albipodus and A. asychis are not monophyletic, and two clearly divergent clades were revealed among seq.enced samples. Our results suggest that the reproductive incompatibility between three exotic strains ofA. asychis was more likely caused by divergence of phylogeny than by symbiotic bacteria.

关键词： Aphelinus Aphidius ITS molecular systematics phylogeny rDNA

Population structure of the Atlantic sand fiddler crab Uca pugilator along the eastern coast of US revealed by molecular data

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Current Zoology 2009年第2期55卷 150-157页

作者： David A. WEESE Denson K. MCLAIN Ann E. PRATT quentin q. fang Department of Biological Sciences Auburn University Department of Biology Georgia Southern University

The Atlantic sand fiddler crab Uca pugilator is an extremely abundant crab found along the eastern coast of the United States. Fiddler crabs have a life cycle with an obligatory planktonic larval phase of 30-90 days,which might be expected to lead to widespread larval dispersal and conseq.ent genetic homogeneity over considerable distances. However,a large amount of morphological and behavioral variation is found between northern and southern populations along the eastern coast. This study was undertaken to determine the population genetic structure of *** and to determine whether these differences may have a genetic basis. The population structure of the fiddler crab was analyzed using 472 individuals collected from 12 sites along the eastern coast. PCR-based single stand conformation polymorphism (SSCP) was used to investigate between-site variation in the mitochondrial 16S rRNA gene of these individuals. Analysis of genetic variation indicated freq.ent gene flow between nearby localities,but much reduced levels between populations separated by larger geographic distances. Thus,despite the potential for high dispersal by planktonic larvae,population differentiation and isolation by distance is evident between northern and southern populations of ***. A high amount of genetic differentiation (F ST =0.3468) was found between northern and southern regions suggesting that the morphological and behavioral differences between these two regions have a genetic basis and may represent subspecies.

关键词： Atlantic sand fiddler crab Uca pugilator Deeapoda Molecular population genetics Gene flow SSCP 16S rDNA

Population structure of the blacklegged tick Ixodes scapularis revealed by SSCP data using the mitochondrial Cyt b and the nuclear ITS1 markers

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动物学报 2004年第2期50卷 176-186页

作者： Tonya R. MIXSON quentin q. fang D. Kelly McLAIN James H. OLIVER Jr Georgia Southern University Department of Biology and Institute of Arthropodology and Parasitology PO Box 8042 Statesboro GA 30460-8042 USA

The population genetic structure of the blacklegged tick Ixodes scapularis was analyzed using 853 individual ticks collected from 12 sites along the eastern seaboard of the United States. PCR-based DNA single strand conformation polymorphism(SSCP) was used for analysis of one haploid locus, the mitochondrial cytochrome b(Cyt b), and one diploid locus, the internal transcribed spacer 1(ITS1) of nuclear ribosomal RNA. Seven haplotypes in the Cyt b locus and 13 genotypes in the ITS1 locus were identified. Population differentiation and isolation by distance were found. Distribution of haplotype and genotype freq.encies across geographic regions suggests that two distinct populations exist along the Eastern Coast of the US. However, genetic variation among individuals within regions was large. This degree of variation suggests freq.ent gene flow between regions. Moreover, overall genetic diversity among individuals was much higher in ticks from the southern population.

关键词： Blacklegged tick Population genetics Genetic variation Gene flow SSCP

Tree species identity and interaction determine vertical forest structure in young planted forests measured by terrestrial laser scanning

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Forest Ecosystems 2024年第3期11卷 266-275页

作者： Mengxi Wang Lander Baeten Frieke Van Coillie Kim Calders Kris Verheyen quentin Ponette Haben Blondeel Bart Muys John Armston Hans Verbeeck q.ForestLab Department of EnvironmentFaculty of Bioscience EngineeringGhent UniversityBelgium Forest&Nature Lab Department of EnvironmentFaculty of Bioscience EngineeringGhent UniversityBelgium Earth and Life Institute Université Catholique de Louvain(UCLouvain)Louvain-la-NeuveBelgium Department of Earth&Environmental Sciences KU LeuvenBelgium Department of Geographical Sciences University of MarylandCollege ParkMDUSA

Vertical forest structure is closely linked to multiple ecosystem characteristics,such as biodiversity,habitat,and *** tree species in planted forests has the potential to create diverse vertical forest structures due to the different physiological and morphological traits of the composing tree ***,the relative importance of species richness,species identity and species interactions for the variation in vertical forest structure remains unclear,mainly because traditional forest inventories do not observe vertical stand structure in *** laser scanning(TLS),however,allows to study vertical forest structure in an unprecedented ***,we used TLS single scan data from 126 plots across three experimental planted forests of a largescale tree diversity experiment in Belgium to study the drivers of vertical forest *** plots were 9–11years old young pure and mixed forests,characterized by four levels of tree species richness ranging from monocultures to four-species mixtures,across twenty composition *** generated vertical plant profiles from the TLS data and derived six stand structural *** mixed models were used to test the effect of species richness on structural *** a hierarchical diversity interaction modelling framework,we further assessed species identity effect and various species interaction effects on the six stand structural *** results showed that species richness did not significantly influence most of the stand structure variables,except for canopy height and foliage height *** identity on the other hand exhibited a significant impact on vertical forest structure across all *** interaction effects were observed to be site-dependent due to varying site conditions and species pools,and rapidly growing tree species tend to dominate these ***,our results highlighted the importance of considering both species identity an

关键词： TreeDivNet FORBIO Stand structural complexity Terrestrial laser scanning Vertical forest structure Tree diversity Planted forests

A Methodology for Assessing Axial Compressor Stability with Inlet Temperature Ramp Distortion

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Journal of Thermal Science 2024年第3期33卷 856-871页

作者： SUN Dakun GU Benhao NING fangfei fang Yibo DONG Xu XU Dengke SUN Xiaofeng School of Energy and Power Engineering Beihang UniversityBeijing102206China Research Institute of Aero-engine Beihang UniversityBeijing102206China

Based on a small perturbation stability model for periodic flow,the effects of inlet total temperature ramp distortion on the axial compressor are investigated and the compressor stability is q.antitatively *** the beginning,a small perturbation stability model for the periodic flow in compressors is proposed,referring to the governing eq.ations of the Harmonic Balance *** stability model is validated on a single-stage low-speed compressor TA36 with uniform inlet ***,the unsteady flow of TA36 with different inlet total temperature ramps and constant back pressure is simulated based on the Harmonic Balance *** on these simulations,the compressor stability is analyzed using the proposed small perturbation ***,the Dynamic Mode Decomposition method is employed to accurately extract pressure *** two parameters of the temperature ramp,ramp rate and Strouhal number,are discussed in this *** results indicate the occurrence and extension of hysteresis loops in the rows,and a decrease in compressor stability with increasing ramp *** performance is divided into two phases,stable and limit,based on the ramp ***,the model predictions suggest that a decrease in period length and an increase in Strouhal number lead to improved compressor *** DMD results imply that for compressors with inlet temperature ramp distortion,the increase of high-order modes and oscillations at the rotor tip is always the signal of decreasing stability.

关键词： axial compressor stability small perturbation model inlet temperature ramp distortion harmonic balance method dynamic mode decomposition method

Seasonal variation of mesoscale eddy intensity in the global ocean

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Acta Oceanologica Sinica 2024年第1期43卷 48-58页

作者： Yongcan Zu Yue fang Shuangwen Sun Libao Gao Yang Yang Guijun Guo First Institute of Oceanography/Key Laboratory of Marine Science and Numerical Modeling Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Mesoscale eddies are a prominent oceanic phenomenon that plays an important role in oceanic mass transport and energy *** by rotational speed,the eddy intensity is one of the most fundamental properties of an ***,the seasonal spatiotemporal variation in eddy intensity has not been examined from a global ocean *** this study,we unveil the seasonal spatiotemporal characteristics of eddy intensity in the global ocean by using the latest satellite-altimetry-derived eddy trajectory data *** results suggest that the eddy intensity has a distinct seasonal variation,reaching a peak in spring while attaining a minimum in autumn in the Northern Hemisphere and the opposite in the Southern *** seasonal variation of eddy intensity is more intense in the tropical-subtropical transition zones within latitudinal bands between 15°and 30°in the western Pacific Ocean,the northwestern Atlantic Ocean,and the eastern Indian Ocean because baroclinic instability in these areas changes *** analysis found that the seasonal variation of baroclinic instability precedes the eddy intensity by a phase of 2–3 months due to the initial perturbations needing time to grow into mesoscale eddies.

关键词： seasonal variation mesoscale eddy intensity baroclinic instability global ocean

Association between luteinizing hormone level decrease on the triggering day and pregnancy outcome for in vitro fertilization/intracytoplasmic sperm injection patients following gonadotropin-releasing hormone antagonist protocol: a retrospective cohor

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生殖与发育医学(英文) 2024年第1期08卷 8-17页

作者： Li q.ng-fang Tang Min-Yue Wang Gui-q.an Chen Xi-Jing Feng Guo-fang Zhu Yi-Min Women’s Hospital School of Medicine 3. Zhejiang University 4. 1 Xueshi Road 5. Hangzhou 310006 6. China

Objective: Optimal luteinizing hormone (LH) levels forin vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) patients following the gonadotropin-releasing hormone (GnRH) antagonist protocol remain controversial. This study aimed to estimate the association between serum LH levels on the triggering day (LHLOT) and clinical pregnancy outcomes in IVF/ICSI patients following the GnRH antagonist ***: We enrolled 4743 IVF/ICSI cycles using flexible or fixed GnRH antagonist protocols between January 2017 and June 2021. The patients were stratified into four groups according to the LHLOT q.artiles (q.–q.). Each group was further divided into two subgroups according to the median basal LH/LHLOT. The main outcomes were clinical pregnancy, birth, and miscarriage rates. Secondary outcomes were oocyte yield, number of MII, fertilized oocytes (2PN), and high-q.ality ***: Serum LHLOT levels were negatively correlated with oocyte yield and the numbers of MII, 2PN, and high-q.ality embryos. Reproductive outcomes were compared among the different q.artiles and subgroups. The absolute difference in the clinical pregnancy rates between the q. and q. groups was 6.4% (47.2%vs. 40.8%,P 3.04 and ≤3.04 were 32.7% and 48.6% (P q.. Within q., the clinical pregnancy rates between the subgroups with basal LH/LHLOT >2.14 and ≤2.14 were 50.2% and 41.9%, respectively (P q.artiles, the q. of serum LHLOT <1.43 IU/L may result in a higher number of oocytes but reduced oocyte maturation and lower clinical pregnancy rates. A decrease in LH levels by approximately 2.14 to 3.04 times compared to basal LH levels may lead to higher clinical pregnancy rates in IVF/ICSI patients following the GnRH antagonist protocol.

关键词： GnRH antagonist IVF/ICSI Luteinizing hormone Ovarian stimulation Reproductive outcomes

Enhancing Data Forwarding Efficiency in SIoT with Multidimensional Social Relations

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Computers, Materials & Continua 2024年第1期78卷 1095-1113页

作者： fang Xu Songhao Jiang Yi Ma Manzoor Ahmed Zenggang Xiong Yuanlin Lyu School of Computer and Information Science Hubei Engineering UniversityXiaogan432000China School of Computer Science and Information Engineering Hubei UniversityWuhan430062China Artificial Intelligence Industrial Technology Research Institute Hubei Engineering UniversityXiaogan432000China

Effective data communication is a crucial aspect of the Social Internet of Things(SIoT)and continues to be a significant research *** paper proposes a data forwarding algorithm based on Multidimensional Social Relations(MSRR)in SIoT to solve this *** proposed algorithm separates message forwarding into intra-and cross-community forwarding by analyzing interest traits and social connections among *** new metrics are defined:the intensity of node social relationships,node activity,and community *** the community,messages are sent by determining which node is most similar to the sender by weighing the strength of social connections and node *** a node performs cross-community forwarding,the message is forwarded to the most reasonable relay community by measuring the node activity and the connection between *** proposed algorithm was compared to three existing routing algorithms in simulation *** indicate that the proposed algorithmsubstantially improves message delivery efficiency while lessening network overhead and enhancing connectivity and coordination in the SIoT context.

关键词： SIoT data forwarding social attributes social relations community

Enhancing the Goos-Hänchen shift based on q.asi-bound states in the continuum through material asymmetric dielectric compound gratings

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Chinese Physics B 2024年第3期33卷 393-400页

作者：江孝伟方彬占春连 College of Optical and Electronic Technology China Jiliang UniversityHangzhou 310018China College of Information Engineering Quzhou College of TechnologyQuzhou 324000China

q.asi-bound state in the continuum(q.IC)resonance is gradually attracting attention and being applied in Goos-Hänchen(GH)shift enhancement due to its high q.ality(q.factor and superior optical ***,symmetry-protected q.IC resonance is often achieved by breaking the geometric symmetry,but few cases are achieved by breaking the material *** paper proposes a dielectric compound grating to achieve a high q.factor and high-reflection symmetry-protectede q.IC resonance based on material *** calculations show that the symmetry-protected q.IC resonance achieved by material asymmetry can significantly increase the GH shift up to-980 times the resonance wavelength,and the maximum GH shift is located at the reflection peak with unity *** paper provides a theoretical basis for designing and fabricating high-performance GH shift tunable metasurfaces/dielectric gratings in the future.

关键词： bound state in the continuum Goos-Hänchen shift dielectric compound grating material asymmetry

A high-performance multi-wavelength optical switch based on multiple Fano resonances in an all-dielectric metastructure

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Optoelectronics Letters 2024年第4期20卷 193-199页

作者： CAO Shuangshuang FAN Xinye fang Wenjing CHEN Huawei BAI Chenglin TONG Cunzhu School of Physics Science and Information Engineering Liaocheng UniversityLiaocheng 252000China Shandong Provincial Key Laboratory of Optical Communication Science and Technology Liaocheng 252000China Liaocheng Key Laboratory of Industrial-Internet Research and Application Liaocheng 252000China Institute of Semiconductors Chinese Academy of SciencesBeijing 100083China State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

The multi-wavelength optical switch based on an all-dielectric metastructure consisting of four asymmetric semi-circular rings was designed and analyzed in this *** Fano resonance modes,which can be explained by bound states in the continuum(BIC)theory,are excited in our structure with a maximum q.factor of about 2450 and a modulation depth close to 100%.By changing the polarization direction of the incident light,the transmission amplitude of Fano resonances can get effectively *** on this tuning property,the metastructure can achieve a multi-wavelength optical switch in the near-infrared region(900—980 nm)and the maximum extinction ratio can reach 38.3 d *** addition,the results indicate that the Fano resonances are sensitive to the changes in the refractive *** sensitivity(S)and the figure of merit(FOM)are 197 nm/RIU and 492 *** proposed metastructure has promising potential in applications such as optical switches,sensors,modulators and lasers.

关键词： dielectric structure resonance