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The functional significance of residual yolk in lizards

Current Zoology 2023年第2期69卷 192-199页

作者： Kun Guo Cai-feng Wang Yu Du Yan-Fu Qu Florentino Brana xiang Ji Zhejiang Provincial Key Laboratory for Water Environment and Marine Biological Resources Protection College of Life and Environmental SciencesWenzhou UniversityWenzhou 325035ZhejiangChina Hainan Key Laboratory of Herpetological Research College of Fisheries and Life ScienceHainan Tropical Ocean UniversitySanya 572022HainanChina College of Life Sciences Nanjing Normal UniversityNanjing 210023China Departamento de Biologia de Orgar smos v Sistemas.Universidad de 0viedo Oviedo 33071Spain

Residual yolk is assumed to be an important source of energy and nutrients during early life in nonmammalian amniotes.Available data show that the mean size of residual yolk is far smaller in lizards than in turtles,snakes,crocodiles,and birds,raising a question of whether residual yolk is of functional significance in lizards.Here,we compared data from 26 lizard species with those from other nonmammalian amniotes to test the hypothesis that residual yolk is functionally less significant in species producing more fully developed offspring.In our sample,species mean offspring water contents ranged from 73%to 84%of body wet mass;species mean proportions of carcass dry mass,fat-body dry mass,and residual yolk dry mass to offspring dry mass ranged from 84%to 99%,0%to 5.0%,and 0%to 14.4%,respectively.Lizards are,on average,more fully developed at hatching or birth than snakes,as revealed by the fact that the mean proportion of carcass dry mass to body dry mass and offspring water contents were both higher in lizards than in snakes.We conclude that the functional significance of residual yolk during early life is generally less evident in lizards.Even in the lizards where residual yolk is of potential functional significance,this portion of yolk contributes little,if any,to postembryonic growth.Future work could usefully collect data across a wider spectrum of reptile taxa to establish a precocial-altricial continuum and test the hypothesis that species with a smaller amount of residual yolk are closer to the precocial end of the continuum.

关键词： carcass fatbody lizards offspring postembryonicgrowth residual yolk

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Polarization of GRB prompt emission and its application to POLAR’s data

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Research in Astronomy and Astrophysics 2021年第3期21卷 43-56页

作者： Mi-xiang Lan Xue-feng Wu Zi-Gao Dai Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210093China

Synchrotron emission polarization is very sensitive to the magnetic field configuration.Recently,polarization of synchrotron emission with a mixed(SM)magnetic field in the gamma-ray burst(GRB)afterglow phase has been developed.Here,we apply these SM models to the GRB prompt phase and compare their polarization properties with that of synchrotron emission in purely ordered(SO)magnetic field.We find that the polarization properties in an SM model are very similar to these in a corresponding SO model(e.g.,synchrotron emission in a mixed magnetic field with an aligned ordered part(SMA)and synchrotron emission with a purely ordered aligned magnetic field(SOA)),only with a lower polarization degree(PD).We also discuss the statistical properties of the models.We find PDs of the simulated bursts are concentrated around 25%for both SOA and synchrotron emission in a purely ordered toroidal magnetic field(SOT),while they can range from 0%to 25%for SMA and synchrotron emission in a mixed magnetic field with a toroidal ordered part(SMT),depending onξ_B value,i.e.,the ratio of magnetic reduction of the ordered magnetic field over that of random magnetic field.From statistics,if PDs of majority GRBs are non-zero,then it favors SO and SM models.Further,if there are some bright GRBs with prominently lower PDs than that of the majority GRBs,it favors SOT(SMT)models;if all the bright GRBs have comparable PDs with the majority ones,it favors SOA(SMA)models.Finally,we apply our results to POLAR’s data and find that~10%time-integrated PDs of the observed bursts favor SMA and SMT models,and theξ_B parameter of these bursts is constrained to be around 1.135.

关键词： gamma-ray burst:general magnetic fields polarization radiation mechanisms:nonthermal

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A survey of heavy–heavy hadronic molecules

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Communications in Theoretical Physics 2021年第12期73卷 86-104页

作者： xiang-Kun Dong feng-Kun Guo Bing-Song Zou CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Physics Central South UniversityChangsha 410083China

The spectrum of hadronic molecules composed of heavy-antiheavy charmed hadrons has been obtained in our previous work.The potentials are constants at the leading order,which are estimated from resonance saturation.The experimental candidates of hadronic molecules,say X(3872),Y(4260),three P_(c)states and P_(cs)(4459),fit the spectrum well.The success in describing the pattern of heavy-antiheavy hadronic molecules stimulates us to give more predictions for the heavy-heavy cases,which are less discussed in literature than the heavy-antiheavy ones.Given that the heavy-antiheavy hadronic molecules,several of which have strong experimental evidence,emerge from the dominant constant interaction from resonance saturation,we find that the existence of many heavy-heavy hadronic molecules is natural.Among these predicted heavy-heavy states we highlight the DD;molecule and the D^(*)∑_(c)^(*)molecules,which are the partners of the famous X(3872)and Pc states.Quite recently,LHCb collaboration reported a doubly charmed tetraquark state,T_(cc),which is in line with our results for the DD^(*)molecule.With the first experimental signal of this new kind of exotic states,the upcoming update of the LHCb experiment as well as other experiments will provide more chances of observing the heavy-heavy hadronic molecules.

关键词： hadronic molecules heavy-heavy systems Bethe-Salpeter equation constant interaction resonance saturation

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Multi-class classification method for steel surface defects with feature noise

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Journal of Iron and Steel Research(International) 2021年第3期28卷 303-315页

作者： Mao-xiang Chu Yao feng Yong-hui Yang Xin Deng School of Electronic and Information Engineering University of Science and Technology LiaoningAnshan114051LiaoningChina

Defect classification is the key task of a steel surface defect detection system.The current defect classification algorithms have not taken the feature noise into consideration.In order to reduce the adverse impact of feature noise,an anti-noise multi-class classification method was proposed for steel surface defects.On the one hand,a novel anti-noise support vector hyper-spheres(ASVHs)classifier was formulated.For N types of defects,the ASVHs classifier built N hyper-spheres.These hyper-spheres were insensitive to feature and label noise.On the other hand,in order to reduce the costs of online time and storage space,the defect samples were pruned by support vector data description with parameter iteration adjustment strategy.In the end,the ASVHs classifier was built with sparse defect samples set and auxiliary information.Experimental results show that the novel multi-class classification method has high efficiency and accuracy for corrupted defect samples in steel surface.

关键词： Steel surface defect Multi-class classification Anti-noise support vector hyper-sphere Parameter iteration adjustment Feature noise

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批判性思维教育融入大学创新型人才培养的机理、理念和路径

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高等教育研究 2023年第10期44卷 57-63页

作者：冯向东华中科技大学教育科学研究院湖北武汉430074

批判性思维教育如何融入大学的创新型人才培养,为培养人才作贡献并获得更大的发展空间,是一个需要讨论和解决的问题。厘清创造性与批判性两种思维品质和思维方式相互作用的机理,确立“批判的目的是推动更高水平、更有价值的创造”的理念... 详细信息

批判性思维教育如何融入大学的创新型人才培养,为培养人才作贡献并获得更大的发展空间,是一个需要讨论和解决的问题。厘清创造性与批判性两种思维品质和思维方式相互作用的机理,确立“批判的目的是推动更高水平、更有价值的创造”的理念,从通识课程教学走向融入人才培养全过程,是探讨解决这一问题的理论依据、前提性基础和可以采取的路径。

关键词：目的性思维批判性思维创造性思维创新型人才培养

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Flexural wave bandgap properties of phononic crystal beams with interval parameters

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Applied Mathematics and Mechanics(English Edition) 2023年第2期44卷 173-188页

作者： Feiyang HE Zhiyu SHI Denghui QIAN Y.K.LU Yujia xiang Xuelei feng State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100Jiangsu ProvinceChina Department of Ophthalmology University of PittsburghPittsburgh 15213PAU.S.A.

Uncertainties are unavoidable in practical engineering,and phononic crystals are no exception.In this paper,the uncertainties are treated as the interval parameters,and an interval phononic crystal beam model is established.A perturbation-based interval finite element method(P-IFEM)and an affine-based interval finite element method(A-IFEM)are proposed to study the dynamic response of this interval phononic crystal beam,based on which an interval vibration transmission analysis can be easily implemented and the safe bandgap can be defined.Finally,two numerical examples are investigated to demonstrate the effectiveness and accuracy of the P-IFEM and A-IFEM.Results show that the safe bandgap range may even decrease by 10%compared with the deterministic bandgap without considering the uncertainties.

关键词： phononic crystal beam interval parameter safe bandgap perturbation-based interval finite element method(P-IFEM) affine-based interval finite element method(A-IFEM) interval vibration transmission analysis

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Nature of spin-lattice coupling in two-dimensional CrI3 and CrGeTe3

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Science China(Physics,Mechanics & Astronomy) 2021年第8期64卷 67-75页

作者： Jing Li JunSheng feng PanShuo Wang ErJun Kan HongJun xiang Key Laboratory of Computational Physical Sciences (Ministry of Education) State Key Laboratory of Surface Physicsand Department of Physics Fudan University Shanghai Qi Zhi Institute School of Physics and Materials Engineering Hefei Normal University Department of Applied Physics and Institution of Energy and Microstructure Nanjing University of Science and Technology Collaborative Innovation Center of Advanced Microstructures

Spin-lattice (SL) coupling plays an important role in spintronic applications given its effects on magnetic,ferroelectric,optical,and thermodynamic properties.Experiments and theoretical calculations have revealed a large SL coupling effect in CrGeTe3and CrI3monolayers.However,the microscopic origin of SL coupling in these systems is still unclear.In this work,we develop a systematic method to explore the atomistic mechanism of SL coupling based on the density functional theory.We find that the first-and second-order SL couplings in ternary system CrGeTe3are considerably stronger than those in binary system CrI3.For the first-order SL coupling,the Cr ions of the magnetic pair and Ge ions positively contribute to the strain enhancement of ferromagnetism in CrGeTe3.However,the Cr ions provide a negative contribution in CrI3.Furthermore,our tight-binding analysis suggests that the p-d hopping in CrGeTe3gradually decreases with the tensile strain,rapidly enhancing the ferromagnetism under the tensile strain.The large frequency shifts in CrGeTe3are caused by the large second-order exchange derivatives (one type of second-order SL coupling) of the Cr ions of the magnetic pair.

关键词： spin-lattice effect two-dimensional magnetic materials first-principle calculation

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Prediction of synthesis cross sections of new moscovium isotopes in fusion‑evaporation reactions

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Nuclear Science and Techniques 2023年第1期34卷 86-101页

作者： Peng‑Hui Chen Hao Wu Zu‑Xing Yang xiang‑Hua Zeng Zhao‑Qing feng School of Physical Science and Technology Yangzhou UniversityYangzhou 225009China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China RIKEN Nishina Center WakoSaitama 351‑0198Japan College of Electrical Power and Energy EngineeringYangzhou UniversityYangzhou 225009China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641China

In the framework of the dinuclear system model,the synthesis mechanism of the superheavy nuclides with atomic numbers Z=112,114,115 in the reactions of projectiles 40,^(48)Ca bombarding on targets^(238)U,^(242)Pu,and^(243)Am within a wide interval of incident energy has been investigated systematically.Based on the available experimental excitation functions,the dependence of calculated synthesis cross-sections on collision orientations has been studied thoroughly.The total kinetic energy(TKE)of these collisions with fixed collision orientation shows orientation dependence,which can be used to predict the tendency of kinetic energy diffusion.The TKE is dependent on incident energies,as discussed in this paper.We applied the method based on the Coulomb barrier distribution function in our calculations.This allowed us to approximately consider all the collision orientations from tip-tip to side-side.The calculations of excitation functions of^(48)Ca+^(238)U,^(48)Ca+242Pu,and^(48)Ca+^(243)Am are in good agreement with the available experimental data.The isospin effect of projectiles on production cross-sections of moscovium isotopes and the influence of the entrance channel effect on the synthesis cross-sections of superheavy nuclei are also discussed in this paper.The synthesis cross-section of new moscovium isotopes 278−286 Mc was predicted to be as large as hundreds of pb in the fusion-evaporation reactions of^(35,37)Cl+^(248)Cf,^(38,40)Ar+^(247)Bk,^(39,41)K+247 Cm,^(40,42,44,46)Ca+^(243)Am,45 Sc+^(244)Pu,and^(46,48,50)Ti+237Np,51 V+^(238)U at some typical excitation energies.

关键词： Dinuclear system model Superheavy nuclei Complete fusion reactions Production cross-section

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Production of neutron-rich actinide isotopes in isobaric collisions via multinucleon transfer reactions

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Nuclear Science and Techniques 2023年第10期34卷 166-177页

作者： Peng-Hui Chen Chang Geng Zu-Xing Yang xiang-Hua Zeng Zhao-Qing feng School of Physical Science and Technology Yangzhou UniversityYangzhou 225009China RIKEN Nishina Center WakoSaitama 351‑0198Japan College of Electrical Power and Energy EngineeringYangzhou UniversityYangzhou 225009China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641China

We systematically calculated the multinucleon transfer reactions of ^(208)Os,^(208)Pt,^(208)Hg,^(208)Pb,^(208)Po,^(208)Rn,^(208)Ra,and ^(132,136) Xe when bombarded on ^(232) Th and ^(248) Cm at Coulomb barrier energies within the dinuclear system model.These results are in good agreement with the available experimental data.The influence of Coulomb and shell effects on actinide production in these reactions has been rigorously studied.We calculated and analyzed the potential energy surface (PES) and total kinetic energy (TKE) mass distributions for the reactions involving ^(208)Hg,^(208)Pb,and ^(208) Po with ^(248) Cm and ^(232)Th.The PES and TKE spectra shed light on the fragment formation mechanisms in multinucleon transfer reactions,with clear indications of isospin and shell effects.The production cross sections for multinucleon transfer products show a strong dependence on isobar projectiles with a mass number A=208.Isobar projectiles with high N/Z ratios are advantageous for generating neutron-rich target-like fragments.Conversely,products induced by isobar projectiles with larger charge numbers tend to shift toward proton-rich regions.The intertwining of the Coulomb potential and shell effect is evident in the production cross sections of actinide isotopes.Drawing from reactions induced by radioactive projectiles,we anticipate the discovery of several new actinide isotopes near the nuclear drip lines,extending our reach into the superheavy nuclei domain.

关键词： Dinuclear system model Isobaric collisions Multinucleon transfer reactions Neutron-rich actinides

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Consensus of single integrator multi-agent systems with directed topology and communication delays

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Control Theory and Technology 2016年第1期14卷 21-27页

作者： xiang XU Lu LIU Gang feng Department of Mechanical and Biomedical Engineering City University of Hong Kong Kowloon Hong Kong China

In this paper, a distributed control scheme has been developed for consensus of single integrator multi-agent systems with directed fixed communication topology for arbitrarily large constant, time-varying or distributed communication delays. It is proved that the closed loop control system can reach consensus with an exponential convergence rate if and only if the topology is quasi-strongly connected. Simulation results are also provided to demonstrate the effectiveness of the proposed controller.

关键词： Consensus directed fixed topology single integrator multi-agent systems communication delays

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