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Bioeffects of Microgravity and hypergravity on Animals

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Chinese Journal of Electrical Engineering 2023年第1期9卷 29-46页

作者： Guofeng Cheng Biao Yu Chao Song Vitalii Zablotskii Xin Zhang High Magnetic Field Laboratory of Chinese Academy of Sciences(CHMFL) HFIPSCASHefei 230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230036China Institute of Physics of the Czech Academy of Sciences Prague 18221Czechia International Magnetobiology Frontier Research Center Science IslandHefei 230031China

Gravity alterations in space cause significant adaptive effects on the human body,including changes to the muscular,skeletal,and vestibular ***,multiple factors besides gravity exist in space;therefore,it is difficult to distinguish gravity-related bioeffects from those of the other factors,including *** everything on the Earth surface is subject to gravity,gravity-induced effects are not explicitly ***,different research methods that have been used in gravity alterations,including parabolic flight,diamagnetic levitation,and centrifuge,are reviewed and *** bioeffects that are reported to be associated with altered gravity in animals are summarized,and the potential risks of hypergravity and microgravity are discussed,with a focus on microgravity,which has been studied more *** should be noted that although various microgravity and hypergravity research methods have their limitations,such as the inevitable magnetic field effects in diamagnetic levitation and short duration of parabolic flight,it is evident that ground-based clinical,animal,and cellular experiments that simulate gravity alterations have served as important and necessary complements to space *** researches not only provide critical and fundamental biological information on the effects of gravity from biomechanics and the biophysical perspectives,but also help in developing future countermeasures for astronauts.

关键词： Gravity microgravity hypergravity bioeffects static magnetic field(SMF)

Biomedical response of femurs in male Wistar rat in chronic hypergravity environments

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Medicine in Novel Technology and Devices 2022年第4期16卷 111-119页

作者： Lu Yu Shuping Wei Biao Han Lilan Gao Yang Zhang Xizheng Zhang Key Laboratory of Biomechanics and Mechanobiology(Beihang University) Ministry of Education Beijing Advanced Innovation Center for Biomedical Engineering School of Biological Science and Medical EngineeringBeihang UniversityBeijing100083China Institute of Medical Service and Technology Academy of Military SciencesTianjin300161China Logistics University of Chinese People's Armed Police Force Tianjin300309China College of Biotechnology Guilin Medical UniversityGuilin541199China School of Mechanical Engineering Tianjin University of TechnologyTianjin300384China

Bone is sensitive to mechanical stimulation and plays a loading-bearing role in the human ***,regulation of bone biomechanical properties in chronic hypergravity environments is still *** this study,male Wistar rats exposed to chronic hypergravity environments(4g,8g,10g,and 20g)for 4 weeks were set as the hypergravity groups,and rats exposed to the normal gravity as the control *** parameters and bone remodeling factors were obtained by means of micro-CT,Western blot,and *** properties of femurs were measured utilizing three points bending test and creep test and were fitted into a viscoelastic-viscoplastic constitutive *** results indicate osteoporosis occurred in femurs of hypergravity ***,the protein and gene expressions of bone remodeling factors(OPG,RANKL,runx2)in hypergravity groups were significantly different from that in the control group,demonstrating that bone formation level increased and bone resorption level ***,mechanical properties of femurs in hypergravity groups showed that Young's modulus of femurs in the 20g group was significantly higher than that in the control *** viscoelastic-viscoplastic properties of bone tissue were changed in hypergravity *** them,the 8g group was closest to the control group in morphology and mechanical *** sum up,the biomechanical response regulation of rat femur under 4-20g chronic hypergravity environments was *** environments could lead to *** balance between bone formation and bone resorption would be disrupted in hypergravity groups due to bone adaptation.20g environment has a significant effect on elastic modulus on *** to the difference in biomechanical response of femurs,the viscoelastic-viscoplastic characteristics of femurs have a nonlinear relationship with hypergravity *** tissue was least affected by 8g hypergravity in morphology and mechani

关键词： hypergravity Biomechanical response Femur Viscoelastic-viscoplastic properties Bone remodeling

Analytical solutions for equivalent elastic compliance of cubic lattice structures subjected to hypergravity conditions

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Acta Mechanica Sinica 2024年第6期40卷 11-19页

作者： Lei Wang Yangkun Du Guannan Wang Chaofeng Lü College of Civil Engineering and Architecture Zhejiang UniversityHangzhou310058China School of Mathematics and Statistics University of GlasgowGlasgowG128QQUK Faculty of Mechanical Engineering and Mechanics Ningbo UniversityNingbo315211China Key Lab of Soft Machines and Smart Devices of Zhejiang Province Zhejiang UniversityHangzhou310027China Soft Matter Research Center Zhejiang UniversityHangzhou310027China

In order to comprehensively understand the mechanical behavior of biological entities and aerospace applications subjected to hypergravity environments,we delve into the impact of hypergravity on the equivalent compliance of cubic lattice *** on the periodic spatial distribution,we employ a unit cell methodology to deduce the homogenized stress-strain relationship for the lattice structures,subsequently obtaining the associated equivalent *** equivalent compliance can be conveniently reduced to instances without hypergravity ***,numerical simulations are executed to validate the derivations and to illustrate that hypergravity indeed affects the mechanical properties of lattice *** introduce a non-dimensional hypergravity factor,which quantifies the impact of hypergravity magnitude relative to the Young’s modulus of the base *** findings reveal that the hypergravity factor influences perpendicular compliance quadratically and parallel compliance ***,the perpendicular shear compliance remains unaffected,whereas the parallel shear compliance experiences an inverse ***,the lattice structure transforms into a gradient material oriented in the hypergravity direction,consequently generating a scale effect.

关键词： hypergravity Cubic lattice structures Equivalent compliance Unit cell approach

Geophysical fluid dynamics in the hypergravity field

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Acta Mechanica Sinica 2024年第6期40卷 3-10页

作者： Harry Yeh School of Civil&Construction Engineering Oregon State UniversityCorvallisOR97331USA

hypergravity can be realized by creating a field imposed by centripetal acceleration in a centrifuge *** an apparatus is often used to test soil response in geotechnical engineering *** we present the potential usage of a centrifuge apparatus to study various topics in *** scaling law associated with hydrodynamics is first reviewed,and the advantage of controlling the body force is *** of the perceived disadvantages in such experiments is the unwanted presence of the Coriolis effect in the ***,we propose exploiting this effect to our advantage to study geophysical fluid-dynamic problems that occur particularly in the equatorial region.

关键词： hypergravity Scaling Geophysical fluid dynamics Centrifuge

Effects of hypergravity on Salt Tolerance of Wheat Seedlings

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Agricultural Science & Technology 2008年第2期9卷 109-111,138页

作者：郭小建郭春绒仲恺农业工程学院生命科学学院山西农业大学文理学院

[ Objective] The study aimed to reveal the effects of hypergravity on salt tolerance of wheat seedlings. [ Method ] The seed germination rate （Gr） and germination index （Gi） of wheat seedlings were measured under hypergravity of 600 × g or 1 000 × g for 4 h and under the stress of 0.4% or 0.9% salt solution. The catalase （CAT） activity and malondialdehyde （MDA） content of wheat seedlings were also measured under 0.4% salt stress. [Result] Compared with seedlings in CK group （no hypergravity or salt stress）, the Gr and Gi of the seedlings in salt stress treatment decreased to different extents; while the Gr and Gi of the seedlings in treatment group （hypergravity and salt stress） increased compared with that in salt stress group. CAT in seedlings of hypergravity treatment was higher than that of CK group and 0.4% salt treatment group, meanwhile the MDA showed an opposite result. [ Conclusion] hypergravity could enhance the salt resistance of wheat in specific range, and hypergravity of 600 × g for 4 h performed better than that of 1 000 ×g for 4 h.

关键词： hypergravity Wheat Salt stress MDA CAT

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Effects of hypergravity on Physiological and Biochemical Characteristics of Chinese Cabbage

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Agricultural Science & Technology 2014年第10期15卷 1631-1633页

作者：段国锋郭星艳王争争郭春绒王如福山西农业大学园艺学院山西太谷030801 山西省微生物研究所山西太原030000 山西农业大学文理学院山西太谷030801 山西农业大学食品科学院山西太谷030801

The Chinese cabbage seed used in this study was Xinfengkang 90. The tested seeds were treated with 1 000×g, 2 000×g and 4 000×g of hypergravity for 20, 40 and 60 min respectively. The Chinese cabbage leaves were col ected at the early seedling stage for the determination of free proline content, POD activity and SOD activity. The results showed the free proline content was lowest in the seeds treated with 40-min 2 000-g gravity, while it was highest for the 60-min 4 000-g gravity treatment. Compared to the control, al the hypergravity treatments inhibited the synthesis of free proline. The POD activity was highest in the seeds treated with 20-min 1 000-g gravity, while it was lowest in the seeds treated with 60-min 2 000-g gravity. Considering the SOD activity, the 40-min 1 000-g gravity treatment was highest, and the 60-min 4 000-g gravity treatment was lowest. lt was indicated that appropriate hypergravity treatment was conducive to increasing the SOD activity.

关键词： Chinese cabbage hypergravity Free proline SOD POD

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The effect of different gravity fields on mass transfer in the rat bone lacunar-canalicular system

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Medicine in Novel Technology and Devices 2023年第1期17卷 141-149页

作者： Hao Wang Jiaming Wang Kangning Li Lilan Gao Aiguo Wang Shuping Wei Linwei Lyu Chunqiu Zhang Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control National Demonstration Center for Experimental Mechanical and Electrical Engineering EducationSchool of Mechanical EngineeringTianjin University of TechnologyTianjin300384PR China Tianjin Academy of Traditional Chinese Medicine Affiliated Hosptial PR China

The bone lacunar-canalicular system(LCS)is an important microscopic infrastructure for signaling and solute transport in bone tissue,which guarantees normal physiological processes of the tissue,but the mass transfer laws in the LCS under different gravity fields have not yet been *** rats were injected intraperitoneally with different concentrations of sodium fluorescein tracer and subjected to mass transfer experiments in the LCS under normal gravity and *** fluorescence distribution in the osteon was observed using laser scanning confocal *** hypergravity environment was provided by a self-designed high-G loading *** fluorescence intensity of the Haversian canal in the osteon was the *** fluorescence intensity of lacunae farther away from the Haversian canal was lower,and the fitted curve was *** the increasing distance from the Haversian canal,the curve first rapidly decreased,and then the decreasing trend gradually became *** promoted mass transfer in the LCS,and the 10 G hypergravity showed varying degrees of fluorescence intensity in each layer of the osteon relative to normal gravity,with intensity enhancements in the range of 132.7–249.0%.The fluorescence intensity was also significantly increased when the tracer concentration was halved and the gravity field magnitude was increased to *** conclusion,hypergravity promoted the transport of solute molecules,nutrients,and signaling molecules within the *** effect of hypergravity on mass transfer in the LCS was greater than that of tracer *** may help to understand bone diseases from a mass transfer perspective.

关键词： Bone Lacunar-canalicular system Mass transfer hypergravity

Influence of different gravitational environments on the mechanotrans-duction in osteoblasts

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Journal of Medical Colleges of PLA(China) 2002年第2期17卷 101-104页

作者：张舒吴兴裕李莹辉 Department of Aerospace Medicine Fourth Military Medical University Xi'an 710033 China Laboratory of Space Cellular and Molecular Biology Institute of space Medico-Engineering Beijing 100094China

Objective: To observe the effects of different gravitational environments on release of prostaglandin E2 in rat calvarial osteoblasts induced by fluid shear stress (FSS) so that to investigate the influence of different gravity on mechanotransduction in osteoblasts. Methods: Osteoblasts were isolated from neonatal rat calvariae and then were set to three groups. Each was cultured in one gravitational environment; 1G terrestrial gravitational environment (control), simulated weightlessness achieved by using clinostat and 3G gravitational environment achieved by using centrifuge for 60 h, then osteoblasts were treated with 0. 5 Pa or 1. 5 Pa FSS in a flow chamber for 1 h. The release of PGE2 in osteoblasts was determined. Results: In 1G gravitational environment, the release of PGE2 was significantly increased along with the sustaining of FSS treatments (P0. 05). While in simulated weightlessness environment group, no detectable release of PGE2 was found with the treatment of 0. 5 Pa FSS (P<0. 01), and the release of PGE2 was delayed and the amount of PGE2 production was remarkably decreased with 1. 5 Pa FSS treatment as compared with that of 1G group (P<0. 01). The responsiveness of osteoblasts cultured in 3G gravitational environment to FSS was similar to that of 1G group. Conclusion: These results indicate that in vitro the mechanotransduction in osteoblasts iss affected by stimulated weightlessness, whereas it is not altered in 3G gravitational environment.

关键词： simulated weightlessness hypergravity rat bone osteoblast fluid shear stress prostaglandin E2

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Gravireception in <i>Phycomyces</i>: Threshold Determination on the Sounding Rocket TEXUS 50

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Journal of Modern Physics 2015年第10期6卷 1381-1389页

作者： Werner Schmidt Fachbereich Biologie Philipps-Universit&#228 t Marburg Marburg Germany Fachbereich Biologie Universit&#228 t Konstanz Konstanz Germany

Under parabolic flight conditions microgravity is not lower than 3 to 5 times 10-2 g. In contrast to parabolic flights, sounding rocket flights are virtually vibrational-free allowing microgravity as low as 10-5 g. Thus, a rotating platform serving as centrifuge allows the precise generation of gravitational forces ranging from 5 to 100 mg (not possible during parabolic flights). On this basis we determined the threshold1 for optical reflection/absorption changes in Phycomyces to be lower than 25 × 10-3 g. This compares well with the threshold determination of gravitropism in Phycomyces on a clinostat centrifuge. Kinetics of gravity-induced absorption changes and gravity as generated by the on-board centrifuge do not coincide but show a distinctive hysteresis with a latency of 4 s (75 mg-ramp, pull-up).

关键词： MDWS (Micro-Dual Wavelength Spectrophotometer) Δ GIAC (Differential Gravity-Induced Absorption Change) Phycomyces blakesleeanus Sporangiophore Micro- and hypergravity Texus 50 Sounding Rocket Gravireception