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Transcriptome Analysis of Crassostrea sikamea (♀) × Crassostrea gigas (♂) Hybrids Under and After thermal stress

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Journal of Ocean University of China 2022年第1期21卷 213-224页

作者： ZHANG Xuekai FAN Chao ZHANG Xingzhi LI Qiongzhen LI Yangchun MA Peizhen YUE Shaobo HUO Zhongming WANG Zhaoping Fisheries College Ocean University of ChinaQingdao 266003China Guangxi Academy of Fisheries Sciences Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy AquacultureNanning 530021China

Crossbreeding is an effective approach to manage the genetic decline in aquaculture.One-way hybrids of Crassostrea sikamea(♀)and Crassostrea gigas(♂)have advantages in growth traits and adaptation to high temperature.Here,we used high-throughput sequencing to analyze the molecular processes in the hybrids under and after thermal stress.The hybrids were cultured in the seawater with an increasing temperature from 25℃to 40℃during 10 hours,which is regarded as the thermal stress stage.Then the temperature decreased from 40℃to 25℃within 2 h,which is regarded as the recovery stage.In this study,1293 significant diffe-rentially expressed genes(DEGs)were obtained under thermal stress,of which 576 were upregulated and 717 were downregulated,and 740 significant differentially expressed genes(DEGs)were obtained in the recovery stage,of which the number of upregulated and downregulated genes was 409 and 331,respectively.The antigen processing and presentation,NOD-like,and NF-kappa B path-ways were significantly enriched during the thermal stress stage.The MAPK and PPAR signaling pathways were significantly enrich-ed during the recovery stage.The HSP70,HSP90,and CANX genes were strongly and rapidly upregulated in the control/thermal stress groups but were slightly less upregulated in the thermal stress/recovery group.These results indicate that the innate immune system or nonspecific immunity was deployed to protect interior tissues from thermal stress.In addition,85%of the mutual DEGs were involved in bidirectional regulation(up/down or down/up)when the oysters were removed from the thermal stress to recover.This study provides preliminary insight into the molecular response of C.sikamea(♀)and C.gigas(♂)hybrids to thermal stress and provides a basis for future studies on temperature-adaptation and the possible expansion of hybrid breeding.

关键词： oyster hybrids gill thermal stress recovery transcriptome

thermal stress damage mechanism in single-crystal germanium caused by 1080 nm laser irradiation

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中国物理B:英文版 2023年第10期32卷 572-578页

作者：沙银川李泽文贾志超韩冰倪晓武 School of Science Nanjing University of Science and TechnologyNanjing 210094China School of Materials Engineering Jinling Institute of TechnologyNanjing 211169China School of Electronic Engineering and Optical Engineering Nanjing University of Science and TechnologyNanjing 210094China

The process of thermal stress damage during 1080 nm laser ablation of single-crystal germanium was recorded in real time using a high-speed charge-coupled device.A three-dimensional finite element numerical model based on Fourier's heat conduction equation,Hooke's law and the Alexander–Hasson equation was developed to analyze the thermal stress damage mechanism involved.The damage morphology of the ablated samples was observed using an optical microscope.The results show that the cooling process has an important influence on fracture in the laser-irradiated region of single-crystal germanium.Fracture is the result of a combination of thermal stress and reduction in local yield strength.

关键词： thermal stress single-crystal germanium fracture damage mechanism

thermal stress reduction of GaAs epitaxial growth on V-groove patterned Si substrates

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Chinese Physics B 2021年第1期30卷 359-364页

作者：杨泽园王俊武国峰黄永清任晓敏季海铭罗帅 State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

We investigate the thermal stresses for GaAs layers grown on V-groove patterned Si substrates by the finite-element method. The results show that the thermal stress distribution near the interface in a patterned substrate is nonuniform,which is far different from that in a planar substrate. Comparing with the planar substrate, the thermal stress is significantly reduced for the Ga As layer on the patterned substrate. The effects of the width of the V-groove, the thickness, and the width of the SiO_(2) mask on the thermal stress are studied. It is found that the SiO_(2) mask and V-groove play a crucial role in the stress of the Ga As layer on Si substrate. The results indicate that when the width of V-groove is 50 nm, the width and the thickness of the SiO_(2) mask are both 100 nm, the Ga As layer is subjected to the minimum stress. Furthermore,Comparing with the planar substrate, the average stress of the Ga As epitaxial layer in the growth window region of the patterned substrate is reduced by 90%. These findings are useful in the optimal designing of growing high-quality Ga As films on patterned Si substrates.

关键词： GaAs on Si thermal stress V-groove finite-element method

thermal stress in Free-standing Diamond Films with Cr Interlayer Destroyed

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Journal of Materials Science & Technology 2010年第11期26卷 991-995页

作者： Zheng Liu,Liangxian Chen,Chengming Li,Lifu Hei,Jianhua Song,Guangchao Chen,Weizhong Tang and Fanxiu Lv School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

thermal stress in large area free-standing diamond films was remarkable during the post-deposition cooling of direct current （DC） arc plasma jet chemical vapor deposition （CVD） process.In this research,the stress release caused by delamination of Cr interlayer was of great importance to ensure the integrity of free-standing diamond film.The effects of Cr interlayer on Mo substrate,namely composite substrate,on thermal stress were investigated.Thermo-mechanical coupling analysis of the thermal stress was applied by finite element analysis （FEA） using ANSYS code.It was found that the interlayer could be destroyed first by the large thermal stress,and then the stress could be released and the probability of diamond film crack initiation would be reduced.The stress concentration at the bent edge of diamond film was also discussed.In addition,diamond films deposited on Mo substrates with and without Cr interlayer were prepared by DC arc plasma jet CVD system and experimental measurements were used to characterize these films.It was found that composite substrate could be an effective method of growing free-standing crack-free diamond films by DC arc plasma jet CVD system when there is no special requirement to the film strength.

关键词： CVD diamond film Cr interlayer thermal stress Finite element analysis

thermal stress cleaving of silicon wafer by pulsed Nd:YAG laser

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Chinese Optics Letters 2010年第10期8卷 1000-1003页

作者：刘剑陆建倪晓武戴罡张梁 Department of Applied Physics Nanjing University of Science & Technology

The applied laser energy absorbed in a local area in laser thermal stress cleaving of brittle materials using a controlled fracture technique produces tensile thermal stress that causes the material to separate along the moving direction of the laser beam. The material separation is similar to crack extension, but the fracture growth is controllable. Using heat transfer theory, we establish a three-dimensional （3D） mathematical thermoelastic calculational model containing a pre-existing crack for a two-point pulsed Nd：YAG laser cleaving silicon wafer. The temperature field and thermal stress field in the silicon wafer are obtained by using the finite element method （FEM）. The distribution of the tensile stress and changes in stress intensity factor around the crack tip are analyzed during the pulse duration. Meanwhile, the mechanism of crack propagation is investigated by analyzing the development of the thermal stress field during the cleaving process.

关键词： Brittle fracture Crack tips Finite element method Laser theory Neodymium Pulsed lasers Semiconducting silicon compounds Silicon wafers thermal stress Thermoelasticity Three dimensional

thermal-stress induced phenomena in two-component material:Part Ⅱ

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Acta Mechanica Sinica 2010年第1期26卷 101-106页

作者： Ladislav Ceniga Institute of Materials Research Slovak Academy of SciencesWatsonova 47040 01 KosiceSlovak Republic

The paper deals with analytical models of the elastic energy gradient Wsq representing an energy barrier. The energy barrier is a surface integral of the elastic energy density Wq. The elastic energy density is induced by thermal stresses acting in an isotropic spherical particle （q = p） with the radius R and in a cubic cell of an isotropic matrix （q = m）. The spherical particle and the matrix are components of a multi-particle-matrix system representing a model system applicable to a real two-component material of a precipitation-matrix type. The multi-particle-matrix system thus consists of periodically distributed isotropic spherical particles and an isotropic infinite matrix. The infinite matrix is imaginarily divided into identical cubic cells with a central spherical particle in each of the cubic cells. The dimension d of the cubic cell then corresponds to an inter-particle distance. The parameters R, d along with the particle volume fraction v = v（R, d） as a function of R, d represent micro- structural characteristics of a real two-component material. The thermal stresses are investigated within the cubic cell, and accordingly are functions of the microstructural charac- teristics. The thermal stresses originate during a cooling pro- cess as a consequence of the difference am - ap in thermal expansion coefficients between the matrix and the particle, am and ap, respectively. The energy barrier Wsq is used for the determination of the thermal-stress induced strengthening aq. The strengthening represents resistance against com- pressive or tensile mechanical loading for am - ap 〉 0 or am - ap 〈 0. respectively.

关键词： thermal stress Strengthening Analyticalmodelling Two-component material

thermal stress MEASUREMENT OF QUARTZ OSCILLATOR MODULE PACKAGING

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Acta Mechanica Solida Sinica 2001年第3期14卷 251-258页

作者： Ji Hongwei Qin Yuwen Chen Jinlong Department of Packaging Engineering Tianjin University of CommerceTianjin 300400China Department of Mechanics Tianjin UniversityTianjin 300072China

The thermal stress of the quartz oscillator module packaging isinvestigated using digital-im- age correlation method (DICM), and theexperimental results are given. Under the quartz oscillator modulepackaging, the quartz oscillator and the Fe-Sn-Cu alloy frame arejoined together with the electroconductive adhesive (PI), and theelectroconductive adhesive needs to be cured twice at 150 deg. C and275 deg. C respective- ly.

关键词： digital-image correlation method (DICM) thermal stress micro-zone strainmeasurement

Cloning ＆ sequence identification of Hsp27 gene and expression analysis of the protein on thermal stress in Lucilia cuprina

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Insect Science 2016年第4期23卷 555-568页

作者： Manish K. Singh Pramod K. Tiwari Center for Genomics Molecular & Human Genetics Jiwaji University Gwafior 474011 Cytogenetics Laboratory Department of Zoology Banaras Hindu University Varanasi 221005 India

Hsp27, a highly conserved small molecular weight heat shock protein, is widely known to be developmentally regulated and heat inducible. Its role in thermotolerance is also implicated. This study is a sequel of our earlier studies to understand the molecular organization of heat shock genes/proteins and their role in development and thermal adaptation in a sheep pest, Lucilia cuprina （blowfly）, which exhibits unusually high adaptability to a variety of environmental stresses, including heat and chemicals. In this report our aim was to understand the evolutionary relationship of Lucilia hsp27 gene/protein with those of other species and its role in thermal adaptation. We sequence characterized the Lchsp27 gene （coding region） and analyzed its expression in various larval and adult tissues under normal as well as heat shock conditions. The nucleotide sequence analysis of 678 bps long-coding region of Lchsp27 exhibited closest evolutionary proximity with Drosophila （90.09%）, which belongs to the same order, Diptera. Heat shock caused significant en- hancement in the expression ofLchsp27 gene in all the larval and adult tissues examined, however, in a tissue specific manner. Significantly, in Malpighian tubules, while the heatinduced level ofhsp27 transcript （mRNA） appeared increased as compared to control, the protein level remained unaltered and nuclear localized. We infer that Lchsp27 may have significant role in the maintenance of cellular homeostasis, particularly, during summer months, when the fly remains exposed to high heat in its natural habitat.

关键词： heat shock protein Hsp27 Lucilia cuprina thermal stress

thermal stress analysis method considering geometric effect of risers in sand mold casting process

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China Foundry 2014年第6期11卷 531-536页

作者： S.Y.Kwak H.Y.Hwang C.Cho e-Design R&D Group Korea Institute of Industrial Technology (KITECH) Department of Virtual Engineering Korea University of Science and Technology(UST) Department of Mechanical Engineering Inha University

Solidif ication and f luid f low analysis using computer simulation is a current common practice. There is also a high demand for thermal stress analysis in the casting process because casting engineers want to control the defects related to thermal stresses, such as large deformation and crack generation during casting. The riser system is an essential part of preventing the shrinkage defects in the casting process, and it has a great inf luence on thermal phenomena. The analysis domain is dramatically expanded by attaching the riser system to a casting product due to its large volume, and it makes FEM mesh generation diff icult. However, it is diff icult to study and solve the above proposed problem caused by riser system using traditional analysis methods which use single numerical method such as FEM or FDM. In this paper, some research information is presented on the effects of the riser system on thermal stress analysis using a FDM/FEM hybrid method in the casting process simulation. The results show the optimal conditions for stress analysis of the riser model in order to save computation time and memory resources.

关键词： thermal stress sand mold casting riser numerical analysis hybrid method simulation