A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to ...A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity.After 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic cells.To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension.The results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly upregulated.In addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated weightlessness.These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness.展开更多
Nucleation of ice by contact takes place when an aerosol particle collides with asurface of supercooled water drop.Aerosol particle may either bounce off the watersurface or be captured on it.McCully et al.(1956) and ...Nucleation of ice by contact takes place when an aerosol particle collides with asurface of supercooled water drop.Aerosol particle may either bounce off the watersurface or be captured on it.McCully et al.(1956) and Rosinski et al.(1963) have shownthat capture of hydrophilic particles was four times larger than of hydrophobic ones.Hydrophobic aerosol particles will nucleate ice preferentially during the brief time ofcontact when they bounce off the surface.Patricles that become captured on the surfacewill float and produce clusters that may nucleate ice at some later time (delayed on surface展开更多
AIM: To evaluate the thickness and volume changes of the choroidal, outer retinal layers(ORL) and retinal pigment epithelium(RPE) in patients with diabetic retinopathy(DR) using optical coherence tomography(OCT) and c...AIM: To evaluate the thickness and volume changes of the choroidal, outer retinal layers(ORL) and retinal pigment epithelium(RPE) in patients with diabetic retinopathy(DR) using optical coherence tomography(OCT) and correlate them with visual acuity.METHODS: We carried out a retrospective observational case series. Consecutive DR patients were recruited for color fundus photography and OCT assessment. The RPE, ORL and choroidal thickness were measured. The correlation with the best-corrected visual acuity(BCVA) was also investigated.RESULTS: The study included 128 eyes, comprising 45 eyes of 25 diabetic macular edema(DME) patients, 34 eyes of 20 DR without DME(non-DME) patients, and 49 eyes of 25 age-matched normal individuals. The choroidal thickness in DR patients were decreased statistically significantly compared with the control group(P<0.05). The mean macular ORL thickness in DME(73.02±15.34 μm) and non-DME groups(76.35±7.32 μm) were decreased statistically significantly compared with the control group(80.20±5.85 μm; P=0.006, P=0.013, respectively). In both the non-DME and DME groups, the RPE thickness were decreased compared with the control group(P<0.05), except in the macular and central ring. The BCVA were significant interactions with the total inner retinal volume and macular RPE thickness in the DME group(r=0.115, P<0.001, r=-0.013, P=0.017, respectively).CONCLUSION: The choroid, ORL and RPE thickness are significantly decreased in DR patients compared with controls in different segments.展开更多
In the present paper the coherent structures in the outer region of turbulent boundary layer were investigated experimentally and analytically. From the observation of the how field over smooth wall, rough wall and sa...In the present paper the coherent structures in the outer region of turbulent boundary layer were investigated experimentally and analytically. From the observation of the how field over smooth wall, rough wall and sand wave wall, it was found that the direct effect of wall on the flow structure can reach y(+1) approximate to 100, and both lateral and vertical vortices exist in the outer region, but the coherent structures in the outer region are mainly the formation, development and decay of the large-scale lateral vortices. By experimental and dynamical analysis, some influence factors and their relations associated with the dynamical process of lateral vortices were deduced.展开更多
The weathering steel (Corten B) was exposed to out-door atmosphere of Hanoi (urban site) and Donghoi (marine site). The results showed the protective ability of corrosion product layer formed on weathering steel in th...The weathering steel (Corten B) was exposed to out-door atmosphere of Hanoi (urban site) and Donghoi (marine site). The results showed the protective ability of corrosion product layer formed on weathering steel in the initial stage. The SEM-EDX analysis detected the presence of chromium and copper in the inner layers of corrosion product formed on weathering steel. These elements improved corrosion resistance of corrosion product layers. In addition, the dense α-FeOOH phase were appeared early in corrosion product which is detected by X-ray diffraction and Micro Raman investigations. The results of polarization and EIS measurements also demonstrated the protectiveness of the corrosion product of weathering steel.展开更多
基金supported by the Army Laboratory Animal Foundation of China,No.SYDW[2020]22(to TC)the Shaanxi Provincial Key R&D Plan General Project of China,No.2022SF-236(to YM)the National Natural Science Foundation of China,No.82202070(to TC)。
文摘A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity.After 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic cells.To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension.The results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly upregulated.In addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated weightlessness.These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness.
基金This work was supported by the National Natural Science Foundation of China under Project(49736200)National Basic Research 973 Project(G1999043503)
文摘Nucleation of ice by contact takes place when an aerosol particle collides with asurface of supercooled water drop.Aerosol particle may either bounce off the watersurface or be captured on it.McCully et al.(1956) and Rosinski et al.(1963) have shownthat capture of hydrophilic particles was four times larger than of hydrophobic ones.Hydrophobic aerosol particles will nucleate ice preferentially during the brief time ofcontact when they bounce off the surface.Patricles that become captured on the surfacewill float and produce clusters that may nucleate ice at some later time (delayed on surface
基金Supported by the Science and Technology Commission of Shanghai Municipality,China(No.16DZ0501100)
文摘AIM: To evaluate the thickness and volume changes of the choroidal, outer retinal layers(ORL) and retinal pigment epithelium(RPE) in patients with diabetic retinopathy(DR) using optical coherence tomography(OCT) and correlate them with visual acuity.METHODS: We carried out a retrospective observational case series. Consecutive DR patients were recruited for color fundus photography and OCT assessment. The RPE, ORL and choroidal thickness were measured. The correlation with the best-corrected visual acuity(BCVA) was also investigated.RESULTS: The study included 128 eyes, comprising 45 eyes of 25 diabetic macular edema(DME) patients, 34 eyes of 20 DR without DME(non-DME) patients, and 49 eyes of 25 age-matched normal individuals. The choroidal thickness in DR patients were decreased statistically significantly compared with the control group(P<0.05). The mean macular ORL thickness in DME(73.02±15.34 μm) and non-DME groups(76.35±7.32 μm) were decreased statistically significantly compared with the control group(80.20±5.85 μm; P=0.006, P=0.013, respectively). In both the non-DME and DME groups, the RPE thickness were decreased compared with the control group(P<0.05), except in the macular and central ring. The BCVA were significant interactions with the total inner retinal volume and macular RPE thickness in the DME group(r=0.115, P<0.001, r=-0.013, P=0.017, respectively).CONCLUSION: The choroid, ORL and RPE thickness are significantly decreased in DR patients compared with controls in different segments.
基金the National Natural Science Foundation of China
文摘In the present paper the coherent structures in the outer region of turbulent boundary layer were investigated experimentally and analytically. From the observation of the how field over smooth wall, rough wall and sand wave wall, it was found that the direct effect of wall on the flow structure can reach y(+1) approximate to 100, and both lateral and vertical vortices exist in the outer region, but the coherent structures in the outer region are mainly the formation, development and decay of the large-scale lateral vortices. By experimental and dynamical analysis, some influence factors and their relations associated with the dynamical process of lateral vortices were deduced.
文摘The weathering steel (Corten B) was exposed to out-door atmosphere of Hanoi (urban site) and Donghoi (marine site). The results showed the protective ability of corrosion product layer formed on weathering steel in the initial stage. The SEM-EDX analysis detected the presence of chromium and copper in the inner layers of corrosion product formed on weathering steel. These elements improved corrosion resistance of corrosion product layers. In addition, the dense α-FeOOH phase were appeared early in corrosion product which is detected by X-ray diffraction and Micro Raman investigations. The results of polarization and EIS measurements also demonstrated the protectiveness of the corrosion product of weathering steel.
