AIM:To investigate the effects of Sonic hedgehog(Shh)gene-modified bone marrow mesenchymal stem cells(MSCs)on graft-induced retinal gliosis and retinal ganglion cells(RGCs)survival in diabetic mice.METHODS:Bone marrow...AIM:To investigate the effects of Sonic hedgehog(Shh)gene-modified bone marrow mesenchymal stem cells(MSCs)on graft-induced retinal gliosis and retinal ganglion cells(RGCs)survival in diabetic mice.METHODS:Bone marrow-derived MSCs were genetically modified with the Shh gene to generate a stably transfected cell line of Shh-modified MSCs(MSC-Shh).Intravitreal injections of MSC-Shh and green fluorescent protein-modified MSCs(MSC-Gfp;control)were administered in diabetic mice.After 4wk,the effects of MSC-Shh on retinal gliosis were evaluated using fundus photography,and markers of gliosis were examined by immunofluorescence and Western blotting.The neurotrophic factors expression and RGCs survival in the host retina were evaluated using Western blotting and immunofluorescence.The mechanisms underlying the effects of MSC-Shh was investigated.RESULTS:A significant reduction of proliferative vitreoretinopathy(PVR)was observed after intravitreal injection of MSC-Shh compared to MSC-Gfp.Significant downregulation of glial fibrillary acidic protein(GFAP)was demonstrated in the host retina after MSC-Shh administration compared to MSC-Gfp.The extracellular signal-regulated kinase 1/2(ERK1/2),protein kinase B(AKT)and phosphatidylin-ositol-3-kinase(PI3K)pathways were significantly downregulated after MSC-Shh administration compared to MSC-Gfp.Brain-derived neurotrophic factor(BDNF)and ciliary neurotrophic factor(CNTF)levels were significantly increased in the host retina,and RGCs loss was significantly prevented after MSC-Shh administration.CONCLUSION:MSC-Shh administration reduces graft-induced reactive gliosis following intravitreal injection in diabetic mice.The ERK1/2,AKT and PI3K pathways are involved in this process.MSC-Shh also increases the levels of neurotrophic factors in the host retina and promoted RGCs survival in diabetic mice.展开更多
Dear Editor,This letter presents a biocompatible cross-shaped magnetic soft robot and investigates its deformation mode control strategy through COMSOL modeling and simulation.Magnetic soft robots offer novel avenues ...Dear Editor,This letter presents a biocompatible cross-shaped magnetic soft robot and investigates its deformation mode control strategy through COMSOL modeling and simulation.Magnetic soft robots offer novel avenues for precise treatment within intricate regions of the human body.展开更多
In the field investigations of the great 1976 Tangshan earthquake in China, several large subsidence areas with remarkable boundary fssures were reported as phenomena of the seismic event. Recently a re-interpretation...In the field investigations of the great 1976 Tangshan earthquake in China, several large subsidence areas with remarkable boundary fssures were reported as phenomena of the seismic event. Recently a re-interpretation of aerial photos taken immediately after the quake revealed that the areas were controlled by a giant fault of about 40 km in length; and subsidences were brought about by the movement of the fault during the shock, not being a consequence of soil liquefaction as suggested in some of the investigations. This discovery has been confirmed by the results of fine geophysical explorations carried out by the Jidong Oilfield Company, PetroChina. The newly discovered fault, named Fuzhuang-Xihe fault, is much longer than the one prevailingly accepted as the seismic fault of the Tangshan earthquake. Moreover, the former seems to be a normal fault, while the latter is regarded as a strike-slip one.展开更多
After several rounds of phased ups and downs of development,rural animal husbandry finally presents a shrinking and depressed development situation under the comprehensive action of the failure of transformation and u...After several rounds of phased ups and downs of development,rural animal husbandry finally presents a shrinking and depressed development situation under the comprehensive action of the failure of transformation and upgrading and the increasing production costs and breeding risks.Actively exploring and guiding the healthy and sound development of rural animal husbandry is not only an important measure to promote the construction of ecological agriculture,but also the main starting point to realize the revitalization of rural industry.This paper analyzes the present situation of the development of rural animal husbandry in recent years,the influence of animal husbandry on the construction of ecological agriculture and the revitalization of rural industry,and puts forward the corresponding measures,in order to promote the steady and efficient development of animal husbandry in the grand strategy of revitalizing rural industry.展开更多
Operating room drug management work directly related to the safety of medication and the scientific nature of medication,the most important content of operating room drug management is to ensure the rational and safe ...Operating room drug management work directly related to the safety of medication and the scientific nature of medication,the most important content of operating room drug management is to ensure the rational and safe use of drugs,to avoid drug abuse and misuse.This paper mainly explores the problems existing in the current operating room drug management process,points out the specific drug management model,and hopes to give full play to the role of drug management to ensure that drugs can be applied scientifically.展开更多
The construction method of continuous paving of the upper and lower base of the water stable macadam base can improve the construction efficiency,overcome the quality problems of the traditional layered paving of the ...The construction method of continuous paving of the upper and lower base of the water stable macadam base can improve the construction efficiency,overcome the quality problems of the traditional layered paving of the upper and lower base,such as untimely curing,slow construction,poor interlayer bonding,contraction joint and interlayer,so as to ensure the construction quality of the water stable macadam.It is also the promotion and application of new technology.展开更多
Lagerstroemia L.(Lythraceae)is a widely distributed genus of trees and shrubs native to tropical and subtropical environments from Southeast Asia to Australia,with numerous species highly valued as ornamentals.Althoug...Lagerstroemia L.(Lythraceae)is a widely distributed genus of trees and shrubs native to tropical and subtropical environments from Southeast Asia to Australia,with numerous species highly valued as ornamentals.Although the plastomes of many species in this genus have been sequenced,the rates of functional gene evolution and their effect on phylogenetic analyses have not been thoroughly examined.We compared three plastome sequence matrices to elucidate how differences in these datasets affected phylogenetic analyses.Robust phylogenetic relationships for Lagerstroemia species were reconstructed based on different plastome sequence partitions and multiple phylogenetic methods.Identification of single-nucleotide variants within different genes also provides basic data on the patterns of functional gene evolution in Lagerstroemia and may provide insights into how those mutations affect protein structure and potentially drive divergence via cytonuclear incompatibility.These results as well as analyses of non-synonymous and synonymous mutations,indicate that heterotachic modes of evolution are present in functional plastome genes and should be accounted for in the analyses of molecular evolution.In addition,divergence events within the Lagerstroemia were dated for the first time.Several of the divergence estimates corresponded to well-known Earth history events,such as the reduction in global temperatures at the Eocene/Oligocene boundary.Our analyses conducted in Lagerstroemia here dissects the various patterns in the divergence of Lagerstroemia and may provide a useful guide to help plant breeders,as well as the necessity of using plastomic data and as possible as to combine evidence from morphological characteristics to investigate the complicated interspecies relationship and the evolutionary dynamics of species.展开更多
Taking 8 parks in Xihu Scenic Area as the survey objects, this study found that there are 77 kinds of shade-tolerant lawns and ground cover plants under the forest in good growth condition, and there are 3 types of ap...Taking 8 parks in Xihu Scenic Area as the survey objects, this study found that there are 77 kinds of shade-tolerant lawns and ground cover plants under the forest in good growth condition, and there are 3 types of application forms: dense forest, sparse forest and forest edge. In response to the existing problems, it is proposed that it is necessary to adhere to principles of ecology, adapt to local conditions and plant suitable varieties in accordance with local conditions, develop and use new varieties of wild shade-tolerant lawns and ground cover plants, and strengthen the promotion of the mixed planting model of shade-tolerant lawns and ground cover plants, so as to provide guidance for the better use of shade-tolerant lawns and ground cover under the forest in the West Lake Scenic Area in the future.展开更多
This study proposed an effective plastic deformation technique,rotating backward extrusion(RBE),for producing high performance AZ80 magnesium alloy cup-shaped pieces.The RBE process was carried on the Gleeble-3500 tes...This study proposed an effective plastic deformation technique,rotating backward extrusion(RBE),for producing high performance AZ80 magnesium alloy cup-shaped pieces.The RBE process was carried on the Gleeble-3500 test machine at 653 K,and the conventional backward extrusion(CBE)was also conducted for comparison.A detailed microstructure analysis was performed using the optical microscopy(OM)and electron back-scatter diffraction(EBSD).The results shown that the equivalent strain and deformation uniformity of the cup pieces could be substantially increased by the RBE process compared with the CBE process.Furthermore,the RBE process could significantly improve the grain refining capacity and the proportion of dynamic recrystallization(DRX),of which the maximum reduction of grain size was 88.60%,and the maximum increase of DRX proportion was 55.30%in the cup bottom.The main deformation mechanism of the RBE process was the discontinuous DRX(DDRX),while the continuous DRX(CDRX)was also occurred in the cup transition.Compared with the CBE sample,the texture of the cup bottom was weakened for the RBE sample.The microhardness value of the RBE sample was higher than that of the CBE sample,which can be attributed to the grain refinement strengthening.展开更多
ObjectiveTo assess the in vivo dynamic blood flow features of posterior optic nerve head (ONH) in rat model of nonarteritic anterior ischemic optic neuropathy (rNAION). MethodsrNAION was established with Rose Bengal a...ObjectiveTo assess the in vivo dynamic blood flow features of posterior optic nerve head (ONH) in rat model of nonarteritic anterior ischemic optic neuropathy (rNAION). MethodsrNAION was established with Rose Bengal and argon green laser in Sprague-Dawley rats. Fundus photography and fundus fluorescein angiography (FFA) were performed to assess the dynamic changes of optic disc in morphology in 90 days and in blood perfusion in 3 hours after the induction of disease. Histological examinations were performed to evaluate the success of modeling. Thedynamic blood flow kinetics of posterior ONH in rNAION were measured by Laser Doppler Flowmetry (LDF) on the day 3, 7, 14, 21, and 40 after the disease induction. One-way ANOVA, Student'st-test and Bonferroni adjustment were used for multiple comparisons of kinetic measurements of blood flow. ResultsOptic disc edema and subsequent resolution associated with the development of optic disc pallor were observed in rNAION. FFA showed that the optic disc was hypofluorescence in the early phase and hyperfluorescence in the late phase. Histological studies suggested edema and loosened tissues of ONH, loss of retinal ganglion cells (RGCs), optic nerve substance and gliosis. Compared to the naive rats, the blood flow kinetics of posterior ONH in rNAION significant reduced at each time point after modeling (F=175.06,P<0.0001). The reductions were specifically remarkable in 14 days after the disease induction (AllP<0.01). Conclusions Continuous blood perfusion reduction was found in rNAION, with significant alteration in 14 days after disease induction. Our results provided important information for understanding the hemodynamic changes in rNAION.展开更多
Last December 2019,a cluster of viral pneumonia cases identified as coronavirus disease 2019(COVID-19)was reported in Wuhan,China.We aimed to explore the frequencies of nasal symptoms in patients with COVID-19,includi...Last December 2019,a cluster of viral pneumonia cases identified as coronavirus disease 2019(COVID-19)was reported in Wuhan,China.We aimed to explore the frequencies of nasal symptoms in patients with COVID-19,including loss of smell and taste,as well as their presentation as the first symptom of the disease and their association with the severity of COVID-19.In this retrospective study,1206 laboratory-confirmed COVID-19 patients were included and followed up by telephone one month after discharged from Tongji Hospital,Wuhan.Demographic data,laboratory values,comorbidities,symptoms,and numerical rating scale scores(0–10)of nasal symptoms were extracted from the hospital medical records,and confirmed or reevaluated by the telephone follow-up.From patients(n=1172)completing follow-up,199(17%)subjects had severe COVID-19 and 342(29.2%)reported nasal symptoms.20.6%COVID-19 patients had loss of taste(median score=6),while 11.4%had loss of smell(median score=5).Loss of taste scores,but not loss of smell scores,were significantly increased in severe vs.nonsevere COVID-19 patients.Interleukin(IL)-6 and lactose dehydrogenase(LDH)serum levels were positively correlated with loss of taste scores.About 80%of COVID-19 patients recovered from smell and taste dysfunction in 2 weeks.In this cohort,only 1 out of 10 hospital admitted patients had loss of smell while 1 out of 5 reported loss of taste which was associated to severity of COVID-19.Most patients recovered smell and taste dysfunctions in 2 weeks.展开更多
AIM: To analyze peripapillary atrophy β/γ zone (PPA-β/γ) and the optic disc ovality index, and to assess their associations with the axial length (AL), refractive error, best corrected visual acuity (BCVA),...AIM: To analyze peripapillary atrophy β/γ zone (PPA-β/γ) and the optic disc ovality index, and to assess their associations with the axial length (AL), refractive error, best corrected visual acuity (BCVA), choroidal thickness (CT), and age in highly myopic eyes. METHODS: This was a retrospective observational case series. The study included 667 patients consecutively examined for highly myopic eyes [spherical equivalent ≤-6.0 diopters (D) and AL≥26 mm] with or without myopic retinopathy. Each patient went through a comprehensive ophthalmological examination that included spectral domain optical coherence tomography (SD-OCT) of the macula, A-mode ultrasonography, and a cycloplegic refraction test. The ovality index and PPA-β/γ area were measured from optic disc photographs. RESULTS: A significant association was seen between PPA-β/γ area and the ovality index (P=0.000, r=-0.232). The PPA-β/γ area increased significantly with a longer AL, older age, worse BCVA, higher refractive error, and thinner choroid (P〈0.01). The oval disc was significantly correlated with a longer AL, older age, worse BCVA, higher refractive error, larger PPA-β/γ area, and thinner choroid (P〈0.01). CONCLUSION: The PPA-β/γ zone and ovality index in highly myopic eyes show distinct associations with the AL, refractive error, BCVA, age, and CT.展开更多
This study explored the association between pupil area variation, heart rate variability, and fatigue, caused by alcohol consumption. Sixteen healthy young male volunteers were enrolled in this study for a series of s...This study explored the association between pupil area variation, heart rate variability, and fatigue, caused by alcohol consumption. Sixteen healthy young male volunteers were enrolled in this study for a series of structured physical examinations. Individual drinking volume was strictly assessed in accordance with the normalized experimental design. The motions of the subjects' pupils, as well as electrocardiograms were recorded by a computerized recording system, both before and after drinking alcohol. After alcohol intake, the pupil diameter, and both low frequency and standard deviation of all heartbeat interval indices of heart rate variability showed significant variations compared with the baseline. In addition, time- and frequency-domain indices of heart rate variability were negatively associated with pupil area. Thus the current study suggests that fatigue status may be determined by significant changes in pupil area and heart rate variability.展开更多
AIM:To investigate the effects of collagen and opticin on the bioactivity of human retinal vascular endothelial cells(hR VECs),and explore its regulations by integrins and RhoA/ROCK1 signal pathway.METHODS:h RVECs wer...AIM:To investigate the effects of collagen and opticin on the bioactivity of human retinal vascular endothelial cells(hR VECs),and explore its regulations by integrins and RhoA/ROCK1 signal pathway.METHODS:h RVECs were cultured in collagen and treated by opticin,and cell-based bioactivity assays of cell proliferation,migration,and adhesion were performed.The expression of integrinα2,integrinβ1,Rho A and ROCK1 were examined with real-time PCR and Western blotting.RESULTS:Collagen could promote cell viability of proliferation and migration(all P<0.05),and enhance the m RNA expression of integrinα2,integrinβ1,Rho A and ROCK1(all P<0.05).Opticin could inhibit proliferation and migration ability of hR VECs cultured in collagen,and reduce the mR NA expression of integrinα2,integrinβ1,RhoA and ROCK1(all P<0.05).CONCLUSION:Collagen and opticin can affect bioactivity of hR VECs,which may be regulated byα2-,β1-integrins and RhoA/ROCK1 signal pathway.展开更多
AIM:To identify and characterize the 100 most influential articles in the field of myopia over the last decades.METHODS:Articles on myopia published between January 1975 and March 2020 were searched through the Web of...AIM:To identify and characterize the 100 most influential articles in the field of myopia over the last decades.METHODS:Articles on myopia published between January 1975 and March 2020 were searched through the Web of Science Core Collection database.Two independent authors reviewed and determined the 100 most cited articles.The characteristics of each eligible article were recorded,including authors,institutions,countries,journals,publication date,total citations(TCs),annual citations(ACs),research focus and article type.RESULTS:The top 100 most influential articles were published between 1983 and 2016,with 1999 as the most prolific year.The mean number of TCs was 288(range:193-537)and the mean number of ACs was 19(range:7-109).Treatment and epidemiology of myopia were the most important research focus.These articles were published in 21 journals led by Ophthalmology(29%)followed by Investigative Ophthalmology&Visual Science(23%).The number of ACs for articles published in the last ten years was significantly higher than that for the other most-cited articles(44 vs 16,Mann-Whitney U test P<0.01).There is no difference in the number of TCs between original articles and review articles,while the number of ACs for review articles was significantly higher than that for original articles(22 vs 17,Mann-Whitney U test P<0.05).CONCLUSION:This bibliometric analysis can provide us with concise information about the development trend of research in the field of myopia in the past few decades,and provide an important reference for researchers to guide future research.展开更多
Wound-field Doubly Salient Generator (WFDSG) has the outstanding advantages of simple structure, high reliability and controllable excitation. However, there exists obvious torque ripple in generator’s input torque, ...Wound-field Doubly Salient Generator (WFDSG) has the outstanding advantages of simple structure, high reliability and controllable excitation. However, there exists obvious torque ripple in generator’s input torque, which has restricted its applications. Based on the concept of electromagnetic torque of WFDSG, the nonlinear formula under no load condition has been derived. Furthermore, it is proved to be reasonable theoretically in comparison with linear and approximate nonlinear formulas. Based on the 12/8 salient prototype, the correctness of nonlinear formula has been verified by comparing the results of virtual displacement method with the results of finite element analysis. At last, the simulation results have been validated by experiments.展开更多
基金Supported by the Natural Science Foundation of Guangdong Province(No.2018A0303130293,No.2023A1515012470).
文摘AIM:To investigate the effects of Sonic hedgehog(Shh)gene-modified bone marrow mesenchymal stem cells(MSCs)on graft-induced retinal gliosis and retinal ganglion cells(RGCs)survival in diabetic mice.METHODS:Bone marrow-derived MSCs were genetically modified with the Shh gene to generate a stably transfected cell line of Shh-modified MSCs(MSC-Shh).Intravitreal injections of MSC-Shh and green fluorescent protein-modified MSCs(MSC-Gfp;control)were administered in diabetic mice.After 4wk,the effects of MSC-Shh on retinal gliosis were evaluated using fundus photography,and markers of gliosis were examined by immunofluorescence and Western blotting.The neurotrophic factors expression and RGCs survival in the host retina were evaluated using Western blotting and immunofluorescence.The mechanisms underlying the effects of MSC-Shh was investigated.RESULTS:A significant reduction of proliferative vitreoretinopathy(PVR)was observed after intravitreal injection of MSC-Shh compared to MSC-Gfp.Significant downregulation of glial fibrillary acidic protein(GFAP)was demonstrated in the host retina after MSC-Shh administration compared to MSC-Gfp.The extracellular signal-regulated kinase 1/2(ERK1/2),protein kinase B(AKT)and phosphatidylin-ositol-3-kinase(PI3K)pathways were significantly downregulated after MSC-Shh administration compared to MSC-Gfp.Brain-derived neurotrophic factor(BDNF)and ciliary neurotrophic factor(CNTF)levels were significantly increased in the host retina,and RGCs loss was significantly prevented after MSC-Shh administration.CONCLUSION:MSC-Shh administration reduces graft-induced reactive gliosis following intravitreal injection in diabetic mice.The ERK1/2,AKT and PI3K pathways are involved in this process.MSC-Shh also increases the levels of neurotrophic factors in the host retina and promoted RGCs survival in diabetic mice.
基金supported by NSFC(62273019,52072015,12332019,U20A20390)the 111 Project(B13003)。
文摘Dear Editor,This letter presents a biocompatible cross-shaped magnetic soft robot and investigates its deformation mode control strategy through COMSOL modeling and simulation.Magnetic soft robots offer novel avenues for precise treatment within intricate regions of the human body.
文摘In the field investigations of the great 1976 Tangshan earthquake in China, several large subsidence areas with remarkable boundary fssures were reported as phenomena of the seismic event. Recently a re-interpretation of aerial photos taken immediately after the quake revealed that the areas were controlled by a giant fault of about 40 km in length; and subsidences were brought about by the movement of the fault during the shock, not being a consequence of soil liquefaction as suggested in some of the investigations. This discovery has been confirmed by the results of fine geophysical explorations carried out by the Jidong Oilfield Company, PetroChina. The newly discovered fault, named Fuzhuang-Xihe fault, is much longer than the one prevailingly accepted as the seismic fault of the Tangshan earthquake. Moreover, the former seems to be a normal fault, while the latter is regarded as a strike-slip one.
文摘After several rounds of phased ups and downs of development,rural animal husbandry finally presents a shrinking and depressed development situation under the comprehensive action of the failure of transformation and upgrading and the increasing production costs and breeding risks.Actively exploring and guiding the healthy and sound development of rural animal husbandry is not only an important measure to promote the construction of ecological agriculture,but also the main starting point to realize the revitalization of rural industry.This paper analyzes the present situation of the development of rural animal husbandry in recent years,the influence of animal husbandry on the construction of ecological agriculture and the revitalization of rural industry,and puts forward the corresponding measures,in order to promote the steady and efficient development of animal husbandry in the grand strategy of revitalizing rural industry.
文摘Operating room drug management work directly related to the safety of medication and the scientific nature of medication,the most important content of operating room drug management is to ensure the rational and safe use of drugs,to avoid drug abuse and misuse.This paper mainly explores the problems existing in the current operating room drug management process,points out the specific drug management model,and hopes to give full play to the role of drug management to ensure that drugs can be applied scientifically.
文摘The construction method of continuous paving of the upper and lower base of the water stable macadam base can improve the construction efficiency,overcome the quality problems of the traditional layered paving of the upper and lower base,such as untimely curing,slow construction,poor interlayer bonding,contraction joint and interlayer,so as to ensure the construction quality of the water stable macadam.It is also the promotion and application of new technology.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(Grant No.LY21C160001)Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants.
文摘Lagerstroemia L.(Lythraceae)is a widely distributed genus of trees and shrubs native to tropical and subtropical environments from Southeast Asia to Australia,with numerous species highly valued as ornamentals.Although the plastomes of many species in this genus have been sequenced,the rates of functional gene evolution and their effect on phylogenetic analyses have not been thoroughly examined.We compared three plastome sequence matrices to elucidate how differences in these datasets affected phylogenetic analyses.Robust phylogenetic relationships for Lagerstroemia species were reconstructed based on different plastome sequence partitions and multiple phylogenetic methods.Identification of single-nucleotide variants within different genes also provides basic data on the patterns of functional gene evolution in Lagerstroemia and may provide insights into how those mutations affect protein structure and potentially drive divergence via cytonuclear incompatibility.These results as well as analyses of non-synonymous and synonymous mutations,indicate that heterotachic modes of evolution are present in functional plastome genes and should be accounted for in the analyses of molecular evolution.In addition,divergence events within the Lagerstroemia were dated for the first time.Several of the divergence estimates corresponded to well-known Earth history events,such as the reduction in global temperatures at the Eocene/Oligocene boundary.Our analyses conducted in Lagerstroemia here dissects the various patterns in the divergence of Lagerstroemia and may provide a useful guide to help plant breeders,as well as the necessity of using plastomic data and as possible as to combine evidence from morphological characteristics to investigate the complicated interspecies relationship and the evolutionary dynamics of species.
基金Supported by the Study on Screening and Application of Shade-tolerant Lawn Plants(S202210341019)。
文摘Taking 8 parks in Xihu Scenic Area as the survey objects, this study found that there are 77 kinds of shade-tolerant lawns and ground cover plants under the forest in good growth condition, and there are 3 types of application forms: dense forest, sparse forest and forest edge. In response to the existing problems, it is proposed that it is necessary to adhere to principles of ecology, adapt to local conditions and plant suitable varieties in accordance with local conditions, develop and use new varieties of wild shade-tolerant lawns and ground cover plants, and strengthen the promotion of the mixed planting model of shade-tolerant lawns and ground cover plants, so as to provide guidance for the better use of shade-tolerant lawns and ground cover under the forest in the West Lake Scenic Area in the future.
基金financially supported by the National Natural Science Foundation of China(No.51775520)the National Key Research and Development Program(No.2016YFB0301103-3)+1 种基金the Key R&D program of Shanxi Province(International Cooperation)(No.201903D421036)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(No.2018002)。
文摘This study proposed an effective plastic deformation technique,rotating backward extrusion(RBE),for producing high performance AZ80 magnesium alloy cup-shaped pieces.The RBE process was carried on the Gleeble-3500 test machine at 653 K,and the conventional backward extrusion(CBE)was also conducted for comparison.A detailed microstructure analysis was performed using the optical microscopy(OM)and electron back-scatter diffraction(EBSD).The results shown that the equivalent strain and deformation uniformity of the cup pieces could be substantially increased by the RBE process compared with the CBE process.Furthermore,the RBE process could significantly improve the grain refining capacity and the proportion of dynamic recrystallization(DRX),of which the maximum reduction of grain size was 88.60%,and the maximum increase of DRX proportion was 55.30%in the cup bottom.The main deformation mechanism of the RBE process was the discontinuous DRX(DDRX),while the continuous DRX(CDRX)was also occurred in the cup transition.Compared with the CBE sample,the texture of the cup bottom was weakened for the RBE sample.The microhardness value of the RBE sample was higher than that of the CBE sample,which can be attributed to the grain refinement strengthening.
基金Fund supported by the National Natural Science Foundation (81670854).
文摘ObjectiveTo assess the in vivo dynamic blood flow features of posterior optic nerve head (ONH) in rat model of nonarteritic anterior ischemic optic neuropathy (rNAION). MethodsrNAION was established with Rose Bengal and argon green laser in Sprague-Dawley rats. Fundus photography and fundus fluorescein angiography (FFA) were performed to assess the dynamic changes of optic disc in morphology in 90 days and in blood perfusion in 3 hours after the induction of disease. Histological examinations were performed to evaluate the success of modeling. Thedynamic blood flow kinetics of posterior ONH in rNAION were measured by Laser Doppler Flowmetry (LDF) on the day 3, 7, 14, 21, and 40 after the disease induction. One-way ANOVA, Student'st-test and Bonferroni adjustment were used for multiple comparisons of kinetic measurements of blood flow. ResultsOptic disc edema and subsequent resolution associated with the development of optic disc pallor were observed in rNAION. FFA showed that the optic disc was hypofluorescence in the early phase and hyperfluorescence in the late phase. Histological studies suggested edema and loosened tissues of ONH, loss of retinal ganglion cells (RGCs), optic nerve substance and gliosis. Compared to the naive rats, the blood flow kinetics of posterior ONH in rNAION significant reduced at each time point after modeling (F=175.06,P<0.0001). The reductions were specifically remarkable in 14 days after the disease induction (AllP<0.01). Conclusions Continuous blood perfusion reduction was found in rNAION, with significant alteration in 14 days after disease induction. Our results provided important information for understanding the hemodynamic changes in rNAION.
基金the Natural Science Foundation of Hubei Province of China(No.2018CFB602)National Key R&D Program of China(No.2018YFC0116800)National Natural Science Foundation of China(Nos:81630024,81920108011,and 81900925)。
文摘Last December 2019,a cluster of viral pneumonia cases identified as coronavirus disease 2019(COVID-19)was reported in Wuhan,China.We aimed to explore the frequencies of nasal symptoms in patients with COVID-19,including loss of smell and taste,as well as their presentation as the first symptom of the disease and their association with the severity of COVID-19.In this retrospective study,1206 laboratory-confirmed COVID-19 patients were included and followed up by telephone one month after discharged from Tongji Hospital,Wuhan.Demographic data,laboratory values,comorbidities,symptoms,and numerical rating scale scores(0–10)of nasal symptoms were extracted from the hospital medical records,and confirmed or reevaluated by the telephone follow-up.From patients(n=1172)completing follow-up,199(17%)subjects had severe COVID-19 and 342(29.2%)reported nasal symptoms.20.6%COVID-19 patients had loss of taste(median score=6),while 11.4%had loss of smell(median score=5).Loss of taste scores,but not loss of smell scores,were significantly increased in severe vs.nonsevere COVID-19 patients.Interleukin(IL)-6 and lactose dehydrogenase(LDH)serum levels were positively correlated with loss of taste scores.About 80%of COVID-19 patients recovered from smell and taste dysfunction in 2 weeks.In this cohort,only 1 out of 10 hospital admitted patients had loss of smell while 1 out of 5 reported loss of taste which was associated to severity of COVID-19.Most patients recovered smell and taste dysfunctions in 2 weeks.
基金Supported by the National Natural Science Foundation of China(No.81570862)the Guangdong Provincial Science and Technology Grant(No.2016A020215096)Guangzhou Science and Technology Project(No.3030901006039)
文摘AIM: To analyze peripapillary atrophy β/γ zone (PPA-β/γ) and the optic disc ovality index, and to assess their associations with the axial length (AL), refractive error, best corrected visual acuity (BCVA), choroidal thickness (CT), and age in highly myopic eyes. METHODS: This was a retrospective observational case series. The study included 667 patients consecutively examined for highly myopic eyes [spherical equivalent ≤-6.0 diopters (D) and AL≥26 mm] with or without myopic retinopathy. Each patient went through a comprehensive ophthalmological examination that included spectral domain optical coherence tomography (SD-OCT) of the macula, A-mode ultrasonography, and a cycloplegic refraction test. The ovality index and PPA-β/γ area were measured from optic disc photographs. RESULTS: A significant association was seen between PPA-β/γ area and the ovality index (P=0.000, r=-0.232). The PPA-β/γ area increased significantly with a longer AL, older age, worse BCVA, higher refractive error, and thinner choroid (P〈0.01). The oval disc was significantly correlated with a longer AL, older age, worse BCVA, higher refractive error, larger PPA-β/γ area, and thinner choroid (P〈0.01). CONCLUSION: The PPA-β/γ zone and ovality index in highly myopic eyes show distinct associations with the AL, refractive error, BCVA, age, and CT.
基金the National Natural Science Foundation of China, No.60879007
文摘This study explored the association between pupil area variation, heart rate variability, and fatigue, caused by alcohol consumption. Sixteen healthy young male volunteers were enrolled in this study for a series of structured physical examinations. Individual drinking volume was strictly assessed in accordance with the normalized experimental design. The motions of the subjects' pupils, as well as electrocardiograms were recorded by a computerized recording system, both before and after drinking alcohol. After alcohol intake, the pupil diameter, and both low frequency and standard deviation of all heartbeat interval indices of heart rate variability showed significant variations compared with the baseline. In addition, time- and frequency-domain indices of heart rate variability were negatively associated with pupil area. Thus the current study suggests that fatigue status may be determined by significant changes in pupil area and heart rate variability.
基金Supported by Natural Science Foundation of Guangdong Province(No.2016A030313364)Project of Administration of Traditional Chinese Medicine of Guangdong Province of China(No.20201065)。
文摘AIM:To investigate the effects of collagen and opticin on the bioactivity of human retinal vascular endothelial cells(hR VECs),and explore its regulations by integrins and RhoA/ROCK1 signal pathway.METHODS:h RVECs were cultured in collagen and treated by opticin,and cell-based bioactivity assays of cell proliferation,migration,and adhesion were performed.The expression of integrinα2,integrinβ1,Rho A and ROCK1 were examined with real-time PCR and Western blotting.RESULTS:Collagen could promote cell viability of proliferation and migration(all P<0.05),and enhance the m RNA expression of integrinα2,integrinβ1,Rho A and ROCK1(all P<0.05).Opticin could inhibit proliferation and migration ability of hR VECs cultured in collagen,and reduce the mR NA expression of integrinα2,integrinβ1,RhoA and ROCK1(all P<0.05).CONCLUSION:Collagen and opticin can affect bioactivity of hR VECs,which may be regulated byα2-,β1-integrins and RhoA/ROCK1 signal pathway.
文摘AIM:To identify and characterize the 100 most influential articles in the field of myopia over the last decades.METHODS:Articles on myopia published between January 1975 and March 2020 were searched through the Web of Science Core Collection database.Two independent authors reviewed and determined the 100 most cited articles.The characteristics of each eligible article were recorded,including authors,institutions,countries,journals,publication date,total citations(TCs),annual citations(ACs),research focus and article type.RESULTS:The top 100 most influential articles were published between 1983 and 2016,with 1999 as the most prolific year.The mean number of TCs was 288(range:193-537)and the mean number of ACs was 19(range:7-109).Treatment and epidemiology of myopia were the most important research focus.These articles were published in 21 journals led by Ophthalmology(29%)followed by Investigative Ophthalmology&Visual Science(23%).The number of ACs for articles published in the last ten years was significantly higher than that for the other most-cited articles(44 vs 16,Mann-Whitney U test P<0.01).There is no difference in the number of TCs between original articles and review articles,while the number of ACs for review articles was significantly higher than that for original articles(22 vs 17,Mann-Whitney U test P<0.05).CONCLUSION:This bibliometric analysis can provide us with concise information about the development trend of research in the field of myopia in the past few decades,and provide an important reference for researchers to guide future research.
文摘Wound-field Doubly Salient Generator (WFDSG) has the outstanding advantages of simple structure, high reliability and controllable excitation. However, there exists obvious torque ripple in generator’s input torque, which has restricted its applications. Based on the concept of electromagnetic torque of WFDSG, the nonlinear formula under no load condition has been derived. Furthermore, it is proved to be reasonable theoretically in comparison with linear and approximate nonlinear formulas. Based on the 12/8 salient prototype, the correctness of nonlinear formula has been verified by comparing the results of virtual displacement method with the results of finite element analysis. At last, the simulation results have been validated by experiments.