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Comparative Transcriptome Analysis of shell-Matrix-Protein Genes and Observation of the shell Microstructure in the Deep-Sea Clam Calyptogena marissinica

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Journal of Ocean University of China 2024年第3期23卷 797-810页

作者： SHI Yu LIU Dongting YAO Gaoyou HE Maoxian CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology Guangdong Provincial Key Laboratory of Applied Marine BiologySouth China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China University of Chinese Academy of Sciences Beijing 100049China

The deep-sea clam Calyptogena marissinica is widely distributed in the Haima cold seep ecosystem on the northwes-tern slope of the South China Sea with low pH values,low temperature and high pressure.Limited information is available on the biomineralization of this species.In this research,we generated a comprehensive transcript dataset of C.marissinica’s mantle tissue,and a total of 19821 unigenes were assembled.Fourteen shell matrix proteins(SMP)-related genes were identified.The qPCR results showed that four out of six prismatic matrix genes(MSP2,MSP5,prisilkin-39,and shematrin),four out of the six nacreous matrix genes(perlucin,pif,pif97,and papilin),and two extrapallial fluid proteins(SPARC and calmodulin)were significantly expressed in the mantle.Both the nacreous and the prismatic layers are chrysanthemum-shaped,which are stacked on the top of each other to form a laminated nacreous structure.The alignment and phylogenetic analysis of MSP-5,Prisilkin-39,Perlucin,and Pif homologues showed that some amino acids of C.marissinica that differed from those detected in other molluscs may cause the different shape of the nacreous and prismatic layers,but do not lead to a change in the species’evolutionary status.These results indicated the conservation of the functions of SMP-related genes in C.marissinica,and the specific shape of the prismatic and nacreous layers of this deep-sea mollusc,which will contribute to the research on the molecular regulation mechanisms of biomineralization in C.marissinica and provide a new perspective to investigate biomineralization in deep-sea clams in general.

关键词： transcriptome biomineralization mantle tissue shell Calyptogena marissinica

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A variational differential quadrature solution to finite deformation problems of hyperelastic shell-type structures:a two-point formulation in Cartesian coordinates

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Applied Mathematics and Mechanics(English Edition) 2022年第8期43卷 1219-1232页

作者： M.FARAJI-OSKOUIE R.ANSARI M.DARVIZEH Faculty of Mechanical Engineering University of GuilanRasht3756Iran

A new numerical approach is presented to compute the large deformations of shell-type structures made of the Saint Venant-Kirchhoff and Neo-Hookean materials based on the seven-parameter shell theory.A work conjugate pair of the first Piola Kirchhoff stress tensor and deformation gradient tensor is considered for the stress and strain measures in the paper.Through introducing the displacement vector,the deformation gradient,and the stress tensor in the Cartesian coordinate system and by means of the chain rule for taking derivative of tensors,the difficulties in using the curvilinear coordinate system are bypassed.The variational differential quadrature(VDQ)method as a pointwise numerical method is also used to discretize the weak form of the governing equations.Being locking-free,the simple implementation,computational efficiency,and fast convergence rate are the main features of the proposed numerical approach.Some well-known benchmark problems are solved to assess the approach.The results indicate that it is capable of addressing the large deformation problems of elastic and hyperelastic shell-type structures efficiently.

关键词： shell large deformation variational differential quadrature(VDQ)technique seven-parameter shell theory first Piola Kirchhoff stress tensor and deformation gradient tensor(P−F)formulation

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Electrostatic Attraction and Repulsion Explained and Modelled Mathematically Using Classical Physics—A Detailed Mechanism Based on Particle Wave Functions

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1050-1062页

作者： Declan Traill Melbourne Australia

The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has been no mechanistic explanation that reveals what causes the charged particles to accelerate, either towards or away from each other. This paper gives a detailed explanation of the phenomena of electrical attraction and repulsion based on my previous work that determined the exact wave-function solutions for both the Electron and the Positron. It is revealed that the effects are caused by wave interactions between the wave functions that result in Electromagnetic reflections of parts of the particle’s wave functions, causing a change in their momenta.

关键词： Electrostatic Electron Positron Coulomb Force Attraction Repulsion Wave Function Electric Magnetic Radiation Pressure shell Theorem 3D Computer Model Quantum

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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1134-1162页

作者： Declan Traill Melbourne Australia

The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles.

关键词： Electron Positron Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS Klein Gordon Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction Repulsion shell Theorem Ehrenfest Virial Normalization Harmonic Oscillator

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Peridynamic shell Model Based on Micro-Beam Bond

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Computer Modeling in Engineering & Sciences 2023年第3期134卷 1975-1995页

作者： Guojun Zheng Zhaomin Yan Yang Xia Ping Hu Guozhe Shen School of Automotive Engineering Dalian University of TechnologyDalian116024China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian116024China

Peridynamics(PD)is a non-localmechanics theory that overcomes the limitations of classical continuummechanics(CCM)in predicting the initiation and propagation of cracks.However,the calculation efficiency of PDmodels is generally lower than that of the traditional finite elementmethod(FEM).Structural idealization can greatly improve the calculation efficiency of PD models for complex structures.This study presents a PD shell model based on the micro-beam bond via the homogenization assumption.First,the deformations of each endpoint of themicro-beam bond are calculated through the interpolation method.Second,the micro-potential energy of the axial,torsional,and bending deformations of the bond can be established from the deformations of endpoints.Finally,the micro moduli of the shellmodel can be obtained via the equivalence principle of strain energy density(SED).In addition,a new fracture criterion based on the SED of the micro-beam bond is adopted for crack simulation.Numerical examples of crack propagation are provided,and the results demonstrate the effectiveness of the proposed PD shell model.

关键词： Peridynamics shell micro-beam bond interpolation method crack propagation homogenization

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shell powder as a novel bio-filler for thermal insulation coatings

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Chinese Journal of Chemical Engineering 2019年第2期27卷 452-458页

作者： Peigen Zhang Jingwen Tang Qiang Tang Minzhao Zhang Luwei Shen Wubian Tian Yamei Zhang Zhengming Sun Jiangsu Key Laboratory of Advanced Metallic Materials School of Materials Science and Engineering Southeast University Jiangsu Key Laboratory of Construction Materials School of Materials Science and Engineering Southeast University

The feasibility of employing shell powder as a novel bio-filler to prepare fluorocarbon coating is demonstrated.According to the relevant Chinese standards, the thermal and mechanical properties of the shell powder-filled fluorocarbon coating were evaluated, and compared with those filled by commercial calcium carbonate. All the shell powder-filled coatings can meet the requirements stated in the relevant standards, and with decreasing the particle size of the shell powders, the performance of the thermal insulation coating is enhanced. The coating(SC3) filled by shell powders with an average particle size of 2.81 μm possesses a better thermal insulation performance than the coating(CC) filled by commercial calcium carbonate. The coating SC3 has comparable adhesive force and washing resistance with the coating CC, and in the washing resistance test, after 2000 cycles, the coating SC3 was still able to cover totally their substrates. This work demonstrates a high value-added disposal method for the aquacultural wastes.

关键词： Bio-filler Fluorocarbon coating shell powder Thermal insulation

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Bifurcation and Chaos of Piezoelectric shell Reinforced with BNNTs Under Electro-Thermo-Mechanical Loadings

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Acta Mechanica Solida Sinica 2019年第1期32卷 120-132页

作者： Jinhua Yang Tao Zhou School of Civil Engineering Changsha University of Science and TechnologyChangsha 410114China

By employing the nonlinear von Karman shell theory and the theory of piezoelect ricity including thermal effec ts,the constitutive relations of the BNNT-reinforced piezoelec trie shell are built.Recurring to the'XY‘rec tangle model,the material consta nts are reckoned.Then,the nonlinear governing equations of the st rue ture are derived t hrough the Reissner variational principle and solved by the fourth-order Runge-Kutta method.In numerical calculations,the effects of temperature,voltage,volume fraction,etc.,on the bifurcation and chaos of piezoelectric shell reinforced with BNNTs are discussed in detail.

关键词： Bifurcation and chaos Piezoelec trie shell BNNTs Reissner variational principle Runge-Kutta method

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Shaking table test and numerical simulation of an isolated cylindrical latticed shell under multiple-support excitations

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Earthquake Engineering and Engineering Vibration 2019年第3期18卷 611-630页

作者： Xue Suduo Shan Mingyue Li Xiongyan Liang Shuanzhu Huang Fuyun Liu Yi Spatial Structures Research Center Beijing University of Technology Beijing 100124 China College of Civil Engineering Fuzhou University Fuzhou 350108 China

In order to study the infl uence of the ground motion spatial eff ect on the seismic response of large span spatial structures with isolation bearings, a single-layer cylindrical latticed shell scale model with a similarity ratio of 1/10 was constructed. An earthquake simulation shaking table test on the response under multiple-support excitations was performed with the high-position seismic isolation method using high damping rubber (HDR) bearings. Small-amplitude sinusoidal waves and seismic wave records with various spectral characteristics were applied to the model. The dynamic characteristics of the model and the seismic isolation eff ect on it were analyzed at varying apparent wave velocities, namely infi nitely great, 1000 m/s, 500 m/s and 250 m/s. Besides, numerical simulations were carried out by Matlab software. According to the comparison results, the numerical results agreed well with the experimental data. Moreover, the results showed that the latticed shell roof exhibited a translational motion as a rigid body after the installation of the HDR bearings with a much lower natural frequency, higher damping ratio and only 1/2~1/8 of the acceleration response peak values. Meanwhile, the structural responses and the bearing deformations at the output end of the seismic waves were greatly increased under multiple-support excitations.

关键词： single-layer cylindrical latticed shell HDR bearings seismic isolation multiple-support excitations shaking table test

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Effects of scallop shell extract on scopolamine-induced memory impairment and MK801-induced locomotor activity

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Asian Pacific Journal of Tropical Medicine 2016年第7期9卷 643-647页

作者： Yasushi Hasegawa Tatsuro Inoue Satoshi Kawaminami Miho Fujita College of Environmental Technology Muroran Institute of Technology

Objective:To evaluate the neuroprotective effects of the organic components of scallop shells(scallop shell extract) on memory impairment and locomotor activity induced by scopolamine or 5-methyl-10,11-dihydro-5H-dibenzo(a,d) cyclohepten-5,10-imine(MK801).Methods:Effect of the scallop shell extract on memory impairment and locomotor activity was investigated using the Y-maze test,the Morris water maze test,and the open field test.Results:Scallop shell extract significantly reduced scopolamine-induced short-term memory impairment and partially reduced scopolamine-induced spatial memory impairment in the Morris water maze test.Scallop shell extract suppressed scopolamine-induced elevation of acetylcholine esterase activity in the cerebral cortex.Treatment with scallop shell extract reversed the increase in locomotor activity induced by scopolamine.Scallop shell extract also suppressed the increase in locomotor activity induced by MK801.Conclusions:Our results provide initial evidence that scallop shell extract reduces scopolamine-induced memory impairment and suppresses MK-801-induced hyperlocomotion.

关键词： Locomotor activity Memory impairment Scallop shell Schizophrenia

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Correlation between Microstructure and Failure Mechanism of Hyriopsis cumingii shell Structure

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Journal of Bionic Engineering 2019年第5期16卷 869-881页

作者： Zhen Zhang Jun Zhu Yajie Chu Zhengnian Chen Shun Guo Junqiang Xu School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing 211167China Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing 211167China School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

In nature,shells exhibit remarkable high toughness and impact resistance to the external load despite their brittle main constituent and simple hierarchical structure.In this work,the structure of the mussel shell Hyriopsis cumingii is analyzed by scanning electron micro scope and atomic force microscope,and the macro/micro compression and impact tests are perfonned.Results show that the shell has a three-layer structure:an outer cuticle layer,a prismatic layer,and a nacreous layer.The stiffer and load-dependent prismatic layer is conducive to improve the impact resistance of shell structure.Fracture morphology after failure proves that cracks are transgranularly propagated inside the prism and aragonite platelet,and the crack deflection and platelet pullout can effectively lock the stress,thereby eventually improving the impact-resistance and toughness of the shell.

关键词： Hyriopsis cumingii shell microstructure macro/micro mechanical property crack propagation

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