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
To address the common issues of wrinkling,tearing,and uneven wall thickness in the actual sheet metal stamp-ing process of the outer ring of needle roller bearings,this study analyzes critical technical indicators suc...To address the common issues of wrinkling,tearing,and uneven wall thickness in the actual sheet metal stamp-ing process of the outer ring of needle roller bearings,this study analyzes critical technical indicators such asforming limits,thickness distribution,and principal strains in the forming process in detail.Three-dimensionalmodels of the concave and convex dies were constructed.The effects of different process parameters,includingstamping speed,edge pressure,sheet metal thickness,and friction coefficient,on the quality of the forming partswere investigated by varying these parameters.Subsequently,the orthogonal experimental method was used todetermine an optimal experimental group from multiple sets of experiments.It was found that under the processparameters of a stamping speed of 3000 mm/s,edge pressure of 2000 N,sheet metal thickness of 0.9 mm,andfriction coefficient of 0.125,the forming quality of the outer ring of the bearing is ideal.展开更多
The external rotor hub motor adopts direct drive mode,no deceleration drive device,and has a compact structure.Its axial size is smaller than that of a deceleration-driven hub motor,which greatly reduces the weight of...The external rotor hub motor adopts direct drive mode,no deceleration drive device,and has a compact structure.Its axial size is smaller than that of a deceleration-driven hub motor,which greatly reduces the weight of the vehicle and increases the cruising range of the vehicle.Because of the limited special working environment and performance requirements,the hub motor has a small internal space and a large heat generation,so it puts forward higher requirements for heat dissipation capacity.For the external rotor hub motor,a new type of in-tank watercooled structure of hub motor was proposed to improve its cooling effect and performance.Firstly,the threedimensional finite element model of the motor is established to analyze the characteristics of motor loss and temperature field distribution.Secondly,the cooling performance of different cooling structures in the tank was studied.Finally,the thermal network model and three-dimensional finite element analysis were used to optimize the water-cooled structure in the tank,and the power density of themotor was improved by improving the cooling performance under the condition of volume limitation of the hub motor.The results show that the cooling effect of the proposed water-cooled structure in the tank is significant under the condition of constant power density.Compared to natural ventilation,the maximum temperature was reduced by 33.13°C and the cooling effect was increased by about 27.7%.展开更多
The reservoir-monolithic type of the controlled release systems is investigated currently,however,the existing kinetic model could not describe the release process well because the release kinetics is rather complicat...The reservoir-monolithic type of the controlled release systems is investigated currently,however,the existing kinetic model could not describe the release process well because the release kinetics is rather complicated.In this paper,a simplified release kinetic model for diffusion-controlled monolithic matrix coated with outer membrane systems is proposed and verified by the experimental data of mercaptopurinum release experiment.It shows that the model can well describe the release mechanism (the relative error is under 3%) when drug loading (C d) is above its solubility limit (C s).At the same time,the release characteristics of special cases (D mD f and D mD f) are discussed theoretically.When D mD f the release rate becomes constant,namely,zero order release,and the release rate is independent of the drug membrane.This result provides the theoretical basis for the system of zero order release as well as how to control the release rate and the amount of drug release.When D mD f,the release rate is dependent on the drug release coefficient in the monolithic matrix,solubility and drug loading but independent of the process in the outer membrane,and it is similar to monolithic matrix type.展开更多
[Objective] This study aimed to investigate the outer membrane protein (OMP) patterns of Escherichia coli 038, 053 and 075 isolates from chickens. [Method] Eight pathogenic E. coil isolates with various serotypes we...[Objective] This study aimed to investigate the outer membrane protein (OMP) patterns of Escherichia coli 038, 053 and 075 isolates from chickens. [Method] Eight pathogenic E. coil isolates with various serotypes were used as experimental materials to extract OMP by using supersonic schizolysis method and Sarcosyl. After SDS-PAGE electrophoresis, OMP patterns of the extracted products were determined based on the OMP model diagram. [Result] OMP of eight E. coil isolates with three serotypes were divided into three patterns, to be specific, 2 075 isolates respectively belonged to OMP-I and OMP-II pattern, 1 053 isolate belonged to OMP-II pattern, and 5 038 isolates belonged to OMP-I and OMP-III pattern. [Conclusion] Experimental results showed that E. coli isolates with the same serotype may belong to completely different OMP patterns, while serologically unrelated isolates may belong to the same OMP pattern. OMP of E. coil isolates with the same serotype may generate genetic differentiation; in addition, OMP of E. coli isolates with different serotypes may have different genetic correlation.展开更多
Objective: To construct a recombinant plasmid containing the outer membrane protein 2 (Omp2) gene of Chlamydia trachomatis and express Omp2 in E.coli. Methods: The omp2 gene of C. trachomatis serovar D was cloned into...Objective: To construct a recombinant plasmid containing the outer membrane protein 2 (Omp2) gene of Chlamydia trachomatis and express Omp2 in E.coli. Methods: The omp2 gene of C. trachomatis serovar D was cloned into pQE30 vector following PCR amplification from genomic DNA. E. coli M15 transformants were induced to express the fusion protein by IPTG and the product was identified by SDS-PAGE and Western blot. Results: Confirmed by enzyme cleavage analysis and DNA sequencing, a correct recombinant plasmid pQE30/omp2 was constructed. The fusion protein from the transformants was approximately 60 kDa in size in SDS-PAGE analysis, which could specially react with anti-6 X His mouse monoclonal IgG antibodies. Conclusion: We successfully expressed Omp2 in E. coli M15, providing an efficient and simple system for assaying the immunological properties of Omp2.展开更多
Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecu...Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their development.This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor EB.Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal diseases.The review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal disorders.The impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways.In vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal microvasculature.Additionally,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and atherogenesis.In retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization.These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering protection against retinal aging and diseases.The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases.Therefore,it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects.展开更多
Semi-floating ring bearing(SFRB) is developed to control the vibration of turbocharger rotor. The outer clearance of SFRB affects the magnitude and frequency of nonlinear whirl motion, which is significant for the d...Semi-floating ring bearing(SFRB) is developed to control the vibration of turbocharger rotor. The outer clearance of SFRB affects the magnitude and frequency of nonlinear whirl motion, which is significant for the design of turbocharger. In order to explore the effects of outer clearance, a transient finite element analysis program for rotor and oil film bearing is built and validated by a published experimental case. The nonlinear dynamic behaviors ofrotor-SFRB system are simulated. According to the simulation results, two representative subsynchronous oscillations excited by the two hearings respectively are discovered. As the outer clearance of SFRB increases from 24 ~tm to 60 pro, the low-frequency subsynchronous oscillation experiences three steps, including a strong start, a gradual recession and a combination with the other one. At the same time, the high-frequency subsynchronous oscillation starts to appear gradually, then strengthens, and finally combines. If gravity and unbalance are neglected, the combination will start starts from high rotor speed and extents to low rotor speed, just like a "zipper". It is found from the quantitative analysis that when the outer clearance increases, the vibration amplitude experiences large value firstly, then reduction, and suddenly increasing after combination. A useful design principle of SFRB outer clearance for minimum vibration amplitude is proposed: the outer clearance value should be chosen to keep the frequency of two subsynchronous oscillations clearly separated and their amplitudes close.展开更多
Idealized numerical simulations are conducted in this study to comparatively investigate the characteristics of the stratiform sector in the outer rainbands of tropical cyclones(TCs)in lower-and upper-layer vertical w...Idealized numerical simulations are conducted in this study to comparatively investigate the characteristics of the stratiform sector in the outer rainbands of tropical cyclones(TCs)in lower-and upper-layer vertical wind shear(VWS)with moderate magnitude.Consistent with the results in previous studies,the outer rainband stratiform sector of the TCs simulated in both experiments is generally located downshear left.Upper-layer VWS tends to produce stronger asymmetric outflow at upper levels in the downshear-left quadrant than lower-layer shear.This stronger asymmetric outflow transports more water vapor radially outward from the inner core to the outer core at upper levels in the downshear-left quadrant in the upper-layer shear experiment.More depositional growth of both graupel and cloud ice thus occurs downshear left in upper layers in the outer core,yielding more diabatic heating and stronger upward motions,particularly in the stratiformdominated part of the stratiform sector in the upper-layer shear experiment.Resultingly,a better-organized stratiform sector in the outer rainbands is found in the upper-layer VWS experiment than in the lower-layer VWS experiment.The diabatic heating associated with the stratiform sector produces strong midlevel outflow on the radially inward side of,and weak midlevel inflow on the radially outward side of,the heating core,with lower-level inflow beneath the midlevel outflow and upper-level inflow above.The upper-layer VWS tends to produce a deeper asymmetric inflow layer in the outer rainband stratiform sector,with more significant lower-level inflow and tangential jets in the upper-layer VWS experiment.展开更多
When a new user accesses the CDMA system, the load will change drastically, and therefore, the advanced outer loop power control (OLPC) technology has to be adopted to enrich the target signal interference ratio (S...When a new user accesses the CDMA system, the load will change drastically, and therefore, the advanced outer loop power control (OLPC) technology has to be adopted to enrich the target signal interference ratio (Silt) and improve the system performance. The existing problems about DS-CDMA outer loop power control for multi-service are introduced and the power control theoretical model is analyzed. System simulation is adopted on how to obtain the theoretical performance and parameter optimization of the power control algorithm. The OLPC algorithm is improved and the performance comparisons between the old algorithm and the improved algorithm are given. The results show good performance of the improved OLPC algorithm and prove the validity of the improved method for multi-service.展开更多
The expanded outer seed coat and the rigid inner seed coat of pomegranate seeds,both affect the sensory qualities of the fruit and its acceptability to consumers.Pomegranate seeds are also an appealing model for the s...The expanded outer seed coat and the rigid inner seed coat of pomegranate seeds,both affect the sensory qualities of the fruit and its acceptability to consumers.Pomegranate seeds are also an appealing model for the study of seed coat differentiation and development.We conducted nontarget metabolic profiling to detect metabolites that contribute to the morphological differentiation of the seed coats along with transcriptomic profiling to unravel the genetic mechanisms underlying this process.Comparisons of metabolites in the lignin biosynthetic pathway accumulating in seed coat layers at different developmental stages revealed that monolignols,including coniferyl alcohol and sinapyl alcohol,greatly accumulated in inner seed coats and monolignol glucosides greatly accumulated in outer seed coats.Strong expression of genes involved in monolignol biosynthesis and transport might explain the spatial patterns of biosynthesis and accumulation of these metabolites.Hemicellulose constituents and flavonoids in particular accumulated in the inner seed coat,and candidate genes that might be involved in their accumulation were also identified.Genes encoding transcription factors regulating monolignol,cellulose,and hemicellulose metabolism were chosen by coexpression analysis.These results provide insights into metabolic factors influencing seed coat differentiation and a reference for studying seed coat developmental biology and pomegranate genetic improvement.展开更多
The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species(P.elliotii,P.oocarpa,P.caribeae,P.merkusii,P.montezumae,and P.insularis) grown in Indonesia were investigated...The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species(P.elliotii,P.oocarpa,P.caribeae,P.merkusii,P.montezumae,and P.insularis) grown in Indonesia were investigated by GC and GC–MS.Generally,the amounts of extractive contents were higher in the inner bark than in the outer bark except for P.merksuii.Fatty acids,monoterpenes,sesquiterpenes,resin acids,triterpenoids,and steroids were detected and quantified.Inner and outer barks differed not only in content of these compounds but also in their composition.Fatty acids and alcohols were the major classes of lipophilic compounds in the outer bark of P.caribeae, P.insularis,and P.montezumae.Steroids and triterpenoids were the dominant compounds identified in the inner bark of P.elliotii,P.insularis,and P.merkusii.Resin acids were the most abundant group in the inner bark of P.oocarpa whereas monoterpenes and sesquiterpenes were recorded in minor quantities in both bark layers of all species.展开更多
Prestin has been identified as a motor protein responsible for outer hair cell (OHC) electromotility and is expressed on the OHC surface. Previous studies revealed that OHC electromotility and its associated nonlinear...Prestin has been identified as a motor protein responsible for outer hair cell (OHC) electromotility and is expressed on the OHC surface. Previous studies revealed that OHC electromotility and its associated nonlinear capacitance were mainly located at the OHC lateral wall and absent at the apical cuticular plate and the basal nucleus region. Immunofluorescent staining for prestin also failed to demonstrate prestin expression at the OHC basal ends in whole-mount preparation of the organ of Corti. However, there lacks a definitive demonstration of the pattern of prestin distribution. The OHC lateral wall has a trilaminate organization and is composed of the plasma membrane, cortical lattice, and subsurface cisternae. In this study, the location of prestin proteins in dissociated OHCs was examined using immunofluorescent staining and confocal microscopy. We found that prestin was uniformly expressed on the basolateral surface, including the basal pole. No staining was seen on the cuticular plate and stereocilia. When co-stained with a membrane marker di-8-ANEPPS, prestin-labeling was found to be in the outer layer of the OHC lateral wall. After separating the plasma membrane from the underlying subsurface cisternae using a hypotonic extracellular solution, prestin-labeling was found to be in the plasma membrane, not the subsurface cisternae. The data show that prestin is expressed in the plasma membrane on the entire OHC basolateral surface.展开更多
Objective This paper aims to develop a monoclonal antibodies (MAbs)- based ELISA for detecting Chlamydophila pneumoniae (C. pneumonioe) antigens in humans with the variable domains (VD) 2 and 3 of the major oute...Objective This paper aims to develop a monoclonal antibodies (MAbs)- based ELISA for detecting Chlamydophila pneumoniae (C. pneumonioe) antigens in humans with the variable domains (VD) 2 and 3 of the major outer membrane protein (MOMPvD2-VD~) and to assess its sensitivity and specificity by comparing with a widely used MAb that is able to recognize the elementary bodies of C. pneumoniae. Methods MOMPvo2-vo3were overexpressed in Escherichia coil and purified by affinity chromatography. Mice were immunized with the recombinant antigen, and hybridomas secreting MAbs were screened. Three stable hybridomas clones were selected and named 5D6, 7G3, and 8C9. The MAbs-based ELISA was scrutinized for species-specific recognition with a number of human throat swab samples from Group I (156 patients with typical respiratory illness clinically confirmed before) and Group II (57 healthy donors). Results In Group I, 55 positive cases were detected by anti-EB MAb-based ELISA, 51 cases were positive by MAbs 5D6-based ELISA, and 33 and 38 cases were positive by MAb 8C9 and 7G3-based ELISA respectively. Of the 57 samples from Group II "healthy donors", 5 were positive and 52 were negative with both anti-EB and 5D6-based tests, while 2 and 3 positive cases were identified by the other two MAb-based ELISAs respectively. Conclusion The novel MOMPvD2.VD3 MAb-based assay may have higher specificity than the anti-EB MAb, which may possibly be used as an alternative tool for the diagnosis of C. pneumoniae infection.展开更多
The ultimate goal in phosphoinositides cellular metabolism is to decipher their global functional organization and coordination of the com- partmentalized signaling processes. In this report we present evidence linkin...The ultimate goal in phosphoinositides cellular metabolism is to decipher their global functional organization and coordination of the com- partmentalized signaling processes. In this report we present evidence linking nuclear phos- phoinositides cycle with endoplasmic reticulum synthesis and function. The rapid transformation of [3H]inositol-labeled phosphoinositides in the intact nuclei (IN) was captured in chase studies for 0-5 min, followed by examination of phosphatidylinositides in the inner nuclear me- mbrane (INM), the outer nuclear membrane (ONM) and endoplasmic reticulum (ER). We revealed that synthesis of phosphatidylinositol phosphates (PIPs) occurs in ONM and the de- phosphorylation takes place in the INM. The rapid transformation of the radiolabeled PIPs in ONM reverberated in their appearance and successive transformation in INM, and in the 5min chased nuclei was tracked to ONM as the re- emerging radiolabeled phosphatidylinositol (PI). These chase-uncovered changes in ONM and INM PIPs profiles allow us to conclude that the observed conversions in the nuclear membrane continuum are induced by the lateral movement of the membrane and its transit from the cytosolic to nuclear and back to cytosolic environment. The suggested membrane synthesisinduced movement provides the means to transport the membrane- and the membrane lipid ligand-associated cytosolic proteins to the intranuclear spaces and renewal of INM. Export of the nuclear components interacting with the modified INM, by exiting from nuclear to cytosolic site, endows ER with a steady influx of the membrane that is conditioned to generate vesicles according to the nucleus delivered templates.展开更多
Pepper mild mottle virus(PMMoV)is a devastating viral pathogen of pepper(Capsicum annuum)but it is unclear whether and how peppers protect against PMMoV infection.The expression of the chloroplast outer membrane prote...Pepper mild mottle virus(PMMoV)is a devastating viral pathogen of pepper(Capsicum annuum)but it is unclear whether and how peppers protect against PMMoV infection.The expression of the chloroplast outer membrane protein 24(OMP24)of C.annuum was upregulated under PMMoV infection and it interacted with PMMoV coat protein(CP).Silencing of OMP24 in either C.annuum or Nicotiana benthamiana facilitated PMMoV infection,whereas overexpression of N.benthamiana OMP24 in transgenic plants inhibited PMMoV infection.Both C.annuum OMP24(CaOMP24)and N.benthamiana OMP24(NbOMP24)localized to the chloroplast and have a moderately hydrophobic transmembrane domain that is necessary for their localization.Overexpression of CaOMP24 induced stromules,perinuclear chloroplast clustering,and accumulation of reactive oxygen species(ROS),the typical defense responses of chloroplasts transferring the retrograde signaling to the nucleus to regulate resistance genes.The expression of PR1 and PR2 was also upregulated significantly in plants overexpressing OMP24.Self-interaction of OMP24 was demonstrated and was required for OMP24-mediated plant defense.Interaction with PMMoV CP interfered with the self-interaction of OMP24 and impaired OMP24-induced stromules,perinuclear chloroplast clustering and ROS accumulation.The results demonstrate the defense function of OMP24 in pepper during viral infection and suggest a possible mechanism by which PMMoV CP modulates the plant defense to facilitate viral infection.展开更多
Aeromonas hydrophila isolates from clinical cases (n=43) were tested against 8 antimicrobial agents and typed by outer membrane protein (OMP) pattern by using sodium dodecyl sulfate gel electrophoresis. All isolat...Aeromonas hydrophila isolates from clinical cases (n=43) were tested against 8 antimicrobial agents and typed by outer membrane protein (OMP) pattern by using sodium dodecyl sulfate gel electrophoresis. All isolates were resistant to ampicillin (MICs, ≥16 μg mL-1) and sulfamonomethoxine (MICs≥64 μg mLl), but susceptible to norfloxacin (MICs,≤0.5 μg mL-1). There was a high incidence of resistance to erythromycin (90.70%) and tylosin (93.02%), while a low incidences of resistance to ciprofloxacin (2.33%), enrofloxacin (2.33%) and florfenicol (4.65%). Six different outer membrane protein patterns were found among 34 isolates by analyzing proteins in the range of 22 to 50 kDa, other than 9 isolates with their respective profiles. The strains with the similar OMP profiles had similar resistances. Compared with the other strains from the same OMP patterns, NB-1, A.Pun and MR-1 had lacked the proteins in the range of 30 to 45 kDa and their resistance to florfenicol substantially increased. It is speculated that the outer membrane protein changes might correlate with decreased susceptibility to florfenicol in the three strains. Some strains which showed completely identical OMP types had a little difference in their resistance to fluoroquinolones, indicating that there might be other factors that were involved in the antimicrobial resistance of A. hydrophila.展开更多
The amount of literature on both melting and thermal conductivity of iron at Earth’s core conditions is overwhelming and the discrepancies are very large.There is a broad range of experimental techniques each of whic...The amount of literature on both melting and thermal conductivity of iron at Earth’s core conditions is overwhelming and the discrepancies are very large.There is a broad range of experimental techniques each of which is flawed to a certain degree,which may explain the discrepancy.In this report,we present new data using a different method for determining the phase behavior and resistivity of iron in the laser-heated diamond cell by measuring the electrical resistance of both solid and liquid iron wires.The experiment avoids some of the major flaws of previous experiments,the most important of which is the detection of the onset of melting.These measurements confirm a shallow melting curve found earlier and the resistivity data imply a trend towards low thermal conductivity in the liquid outer core.展开更多
The elasto-gravitational deformation response of the Earths solid parts to the perturbations of the pressure and gravity on the core-mantle boundary (CMB) and the solid inner core boundary (ICB), due to the dynamical ...The elasto-gravitational deformation response of the Earths solid parts to the perturbations of the pressure and gravity on the core-mantle boundary (CMB) and the solid inner core boundary (ICB), due to the dynamical behaviors of the fluid outer core (FOC), is discussed. The internal load Love numbers, which are formulized in a general form in this study, are employed to describe the Earths deformation. The preliminary reference Earth model (PREM) is used as an example to calculate the internal load Love numbers on the Earths surface, CMB and ICB, respectively. The characteristics of the Earths deformation variation with the depth and the perturbation periods on the boundaries of the FOC are also investigated. The numerical results indicate that the internal load Love numbers decrease quickly with the increasing degree of the spherical harmonics of the displacement and depend strongly on the perturbation frequencies, especially on the high frequencies. The results, obtained in this work, can be used to construct the boundary conditions for the core dynamics of the long-period oscillations of the Earths fluid outer core.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supported by the China Postdoctoral Science Foundation(Grant No.2022M721395)the National Natural Science Foundation of China(Grant No.72072089).
文摘To address the common issues of wrinkling,tearing,and uneven wall thickness in the actual sheet metal stamp-ing process of the outer ring of needle roller bearings,this study analyzes critical technical indicators such asforming limits,thickness distribution,and principal strains in the forming process in detail.Three-dimensionalmodels of the concave and convex dies were constructed.The effects of different process parameters,includingstamping speed,edge pressure,sheet metal thickness,and friction coefficient,on the quality of the forming partswere investigated by varying these parameters.Subsequently,the orthogonal experimental method was used todetermine an optimal experimental group from multiple sets of experiments.It was found that under the processparameters of a stamping speed of 3000 mm/s,edge pressure of 2000 N,sheet metal thickness of 0.9 mm,andfriction coefficient of 0.125,the forming quality of the outer ring of the bearing is ideal.
基金supported by National Science Foundation of China(Grant No.51705306).
文摘The external rotor hub motor adopts direct drive mode,no deceleration drive device,and has a compact structure.Its axial size is smaller than that of a deceleration-driven hub motor,which greatly reduces the weight of the vehicle and increases the cruising range of the vehicle.Because of the limited special working environment and performance requirements,the hub motor has a small internal space and a large heat generation,so it puts forward higher requirements for heat dissipation capacity.For the external rotor hub motor,a new type of in-tank watercooled structure of hub motor was proposed to improve its cooling effect and performance.Firstly,the threedimensional finite element model of the motor is established to analyze the characteristics of motor loss and temperature field distribution.Secondly,the cooling performance of different cooling structures in the tank was studied.Finally,the thermal network model and three-dimensional finite element analysis were used to optimize the water-cooled structure in the tank,and the power density of themotor was improved by improving the cooling performance under the condition of volume limitation of the hub motor.The results show that the cooling effect of the proposed water-cooled structure in the tank is significant under the condition of constant power density.Compared to natural ventilation,the maximum temperature was reduced by 33.13°C and the cooling effect was increased by about 27.7%.
文摘The reservoir-monolithic type of the controlled release systems is investigated currently,however,the existing kinetic model could not describe the release process well because the release kinetics is rather complicated.In this paper,a simplified release kinetic model for diffusion-controlled monolithic matrix coated with outer membrane systems is proposed and verified by the experimental data of mercaptopurinum release experiment.It shows that the model can well describe the release mechanism (the relative error is under 3%) when drug loading (C d) is above its solubility limit (C s).At the same time,the release characteristics of special cases (D mD f and D mD f) are discussed theoretically.When D mD f the release rate becomes constant,namely,zero order release,and the release rate is independent of the drug membrane.This result provides the theoretical basis for the system of zero order release as well as how to control the release rate and the amount of drug release.When D mD f,the release rate is dependent on the drug release coefficient in the monolithic matrix,solubility and drug loading but independent of the process in the outer membrane,and it is similar to monolithic matrix type.
基金Supported by China Postdoctoral Science Foundation(20100470565)Science and Technology Support Program of Hebei Province(10960408D)+1 种基金Project of Science and technology Bureau of Shijiazhuang(1150093A)Science and Technology Development Project of Qinhuangdao City(201101A182)~~
文摘[Objective] This study aimed to investigate the outer membrane protein (OMP) patterns of Escherichia coli 038, 053 and 075 isolates from chickens. [Method] Eight pathogenic E. coil isolates with various serotypes were used as experimental materials to extract OMP by using supersonic schizolysis method and Sarcosyl. After SDS-PAGE electrophoresis, OMP patterns of the extracted products were determined based on the OMP model diagram. [Result] OMP of eight E. coil isolates with three serotypes were divided into three patterns, to be specific, 2 075 isolates respectively belonged to OMP-I and OMP-II pattern, 1 053 isolate belonged to OMP-II pattern, and 5 038 isolates belonged to OMP-I and OMP-III pattern. [Conclusion] Experimental results showed that E. coli isolates with the same serotype may belong to completely different OMP patterns, while serologically unrelated isolates may belong to the same OMP pattern. OMP of E. coil isolates with the same serotype may generate genetic differentiation; in addition, OMP of E. coli isolates with different serotypes may have different genetic correlation.
基金This work was supported in part by grants from the Department of Science and Technology of Hunan Province (No. 01SSY2008-6) the Department of Health of Hunan Province (No. B2003-078).
文摘Objective: To construct a recombinant plasmid containing the outer membrane protein 2 (Omp2) gene of Chlamydia trachomatis and express Omp2 in E.coli. Methods: The omp2 gene of C. trachomatis serovar D was cloned into pQE30 vector following PCR amplification from genomic DNA. E. coli M15 transformants were induced to express the fusion protein by IPTG and the product was identified by SDS-PAGE and Western blot. Results: Confirmed by enzyme cleavage analysis and DNA sequencing, a correct recombinant plasmid pQE30/omp2 was constructed. The fusion protein from the transformants was approximately 60 kDa in size in SDS-PAGE analysis, which could specially react with anti-6 X His mouse monoclonal IgG antibodies. Conclusion: We successfully expressed Omp2 in E. coli M15, providing an efficient and simple system for assaying the immunological properties of Omp2.
基金supported by the Start-up Fund for new faculty from the Hong Kong Polytechnic University(PolyU)(A0043215)(to SA)the General Research Fund and Research Impact Fund from the Hong Kong Research Grants Council(15106018,R5032-18)(to DYT)+1 种基金the Research Center for SHARP Vision in PolyU(P0045843)(to SA)the InnoHK scheme from the Hong Kong Special Administrative Region Government(to DYT).
文摘Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their development.This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor EB.Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal diseases.The review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal disorders.The impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways.In vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal microvasculature.Additionally,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and atherogenesis.In retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization.These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering protection against retinal aging and diseases.The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases.Therefore,it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects.
基金Supported by National Natural Science Foundation of China(Grant No51506108)
文摘Semi-floating ring bearing(SFRB) is developed to control the vibration of turbocharger rotor. The outer clearance of SFRB affects the magnitude and frequency of nonlinear whirl motion, which is significant for the design of turbocharger. In order to explore the effects of outer clearance, a transient finite element analysis program for rotor and oil film bearing is built and validated by a published experimental case. The nonlinear dynamic behaviors ofrotor-SFRB system are simulated. According to the simulation results, two representative subsynchronous oscillations excited by the two hearings respectively are discovered. As the outer clearance of SFRB increases from 24 ~tm to 60 pro, the low-frequency subsynchronous oscillation experiences three steps, including a strong start, a gradual recession and a combination with the other one. At the same time, the high-frequency subsynchronous oscillation starts to appear gradually, then strengthens, and finally combines. If gravity and unbalance are neglected, the combination will start starts from high rotor speed and extents to low rotor speed, just like a "zipper". It is found from the quantitative analysis that when the outer clearance increases, the vibration amplitude experiences large value firstly, then reduction, and suddenly increasing after combination. A useful design principle of SFRB outer clearance for minimum vibration amplitude is proposed: the outer clearance value should be chosen to keep the frequency of two subsynchronous oscillations clearly separated and their amplitudes close.
基金the National Key Research and Development Program of China(Grant No.2017YFC1501601)the Key Program of the Ministry of Science and Technology of China(Grant No.2017YFE0107700)the National Natural Science Foundation of China(Grant Nos.41875054,41730961,41730960,and 41775065).
文摘Idealized numerical simulations are conducted in this study to comparatively investigate the characteristics of the stratiform sector in the outer rainbands of tropical cyclones(TCs)in lower-and upper-layer vertical wind shear(VWS)with moderate magnitude.Consistent with the results in previous studies,the outer rainband stratiform sector of the TCs simulated in both experiments is generally located downshear left.Upper-layer VWS tends to produce stronger asymmetric outflow at upper levels in the downshear-left quadrant than lower-layer shear.This stronger asymmetric outflow transports more water vapor radially outward from the inner core to the outer core at upper levels in the downshear-left quadrant in the upper-layer shear experiment.More depositional growth of both graupel and cloud ice thus occurs downshear left in upper layers in the outer core,yielding more diabatic heating and stronger upward motions,particularly in the stratiformdominated part of the stratiform sector in the upper-layer shear experiment.Resultingly,a better-organized stratiform sector in the outer rainbands is found in the upper-layer VWS experiment than in the lower-layer VWS experiment.The diabatic heating associated with the stratiform sector produces strong midlevel outflow on the radially inward side of,and weak midlevel inflow on the radially outward side of,the heating core,with lower-level inflow beneath the midlevel outflow and upper-level inflow above.The upper-layer VWS tends to produce a deeper asymmetric inflow layer in the outer rainband stratiform sector,with more significant lower-level inflow and tangential jets in the upper-layer VWS experiment.
基金the National Natural Science Foundation of China (60532030).
文摘When a new user accesses the CDMA system, the load will change drastically, and therefore, the advanced outer loop power control (OLPC) technology has to be adopted to enrich the target signal interference ratio (Silt) and improve the system performance. The existing problems about DS-CDMA outer loop power control for multi-service are introduced and the power control theoretical model is analyzed. System simulation is adopted on how to obtain the theoretical performance and parameter optimization of the power control algorithm. The OLPC algorithm is improved and the performance comparisons between the old algorithm and the improved algorithm are given. The results show good performance of the improved OLPC algorithm and prove the validity of the improved method for multi-service.
基金supported by the Natural Science Foundation of Anhui Province(1708085MC85).
文摘The expanded outer seed coat and the rigid inner seed coat of pomegranate seeds,both affect the sensory qualities of the fruit and its acceptability to consumers.Pomegranate seeds are also an appealing model for the study of seed coat differentiation and development.We conducted nontarget metabolic profiling to detect metabolites that contribute to the morphological differentiation of the seed coats along with transcriptomic profiling to unravel the genetic mechanisms underlying this process.Comparisons of metabolites in the lignin biosynthetic pathway accumulating in seed coat layers at different developmental stages revealed that monolignols,including coniferyl alcohol and sinapyl alcohol,greatly accumulated in inner seed coats and monolignol glucosides greatly accumulated in outer seed coats.Strong expression of genes involved in monolignol biosynthesis and transport might explain the spatial patterns of biosynthesis and accumulation of these metabolites.Hemicellulose constituents and flavonoids in particular accumulated in the inner seed coat,and candidate genes that might be involved in their accumulation were also identified.Genes encoding transcription factors regulating monolignol,cellulose,and hemicellulose metabolism were chosen by coexpression analysis.These results provide insights into metabolic factors influencing seed coat differentiation and a reference for studying seed coat developmental biology and pomegranate genetic improvement.
基金supported by JASSO(Japan Student Services Organization)DPP Grant 2016(Faculty of Forestry,UGM)
文摘The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species(P.elliotii,P.oocarpa,P.caribeae,P.merkusii,P.montezumae,and P.insularis) grown in Indonesia were investigated by GC and GC–MS.Generally,the amounts of extractive contents were higher in the inner bark than in the outer bark except for P.merksuii.Fatty acids,monoterpenes,sesquiterpenes,resin acids,triterpenoids,and steroids were detected and quantified.Inner and outer barks differed not only in content of these compounds but also in their composition.Fatty acids and alcohols were the major classes of lipophilic compounds in the outer bark of P.caribeae, P.insularis,and P.montezumae.Steroids and triterpenoids were the dominant compounds identified in the inner bark of P.elliotii,P.insularis,and P.merkusii.Resin acids were the most abundant group in the inner bark of P.oocarpa whereas monoterpenes and sesquiterpenes were recorded in minor quantities in both bark layers of all species.
基金supported by NIH (NIDCD DC 05989)NSFC (30600700, 30772413)
文摘Prestin has been identified as a motor protein responsible for outer hair cell (OHC) electromotility and is expressed on the OHC surface. Previous studies revealed that OHC electromotility and its associated nonlinear capacitance were mainly located at the OHC lateral wall and absent at the apical cuticular plate and the basal nucleus region. Immunofluorescent staining for prestin also failed to demonstrate prestin expression at the OHC basal ends in whole-mount preparation of the organ of Corti. However, there lacks a definitive demonstration of the pattern of prestin distribution. The OHC lateral wall has a trilaminate organization and is composed of the plasma membrane, cortical lattice, and subsurface cisternae. In this study, the location of prestin proteins in dissociated OHCs was examined using immunofluorescent staining and confocal microscopy. We found that prestin was uniformly expressed on the basolateral surface, including the basal pole. No staining was seen on the cuticular plate and stereocilia. When co-stained with a membrane marker di-8-ANEPPS, prestin-labeling was found to be in the outer layer of the OHC lateral wall. After separating the plasma membrane from the underlying subsurface cisternae using a hypotonic extracellular solution, prestin-labeling was found to be in the plasma membrane, not the subsurface cisternae. The data show that prestin is expressed in the plasma membrane on the entire OHC basolateral surface.
基金supported by grants from the National Natural Science Foundation of China (Grant No. 30901352)Innovative Research Team in University of Hunan Province (Number: [2008] 51)Hunan Provincial Innovation Foundation for Postgraduate and Hunan Provincial Training and Innovation Base for Post-graduate
文摘Objective This paper aims to develop a monoclonal antibodies (MAbs)- based ELISA for detecting Chlamydophila pneumoniae (C. pneumonioe) antigens in humans with the variable domains (VD) 2 and 3 of the major outer membrane protein (MOMPvD2-VD~) and to assess its sensitivity and specificity by comparing with a widely used MAb that is able to recognize the elementary bodies of C. pneumoniae. Methods MOMPvo2-vo3were overexpressed in Escherichia coil and purified by affinity chromatography. Mice were immunized with the recombinant antigen, and hybridomas secreting MAbs were screened. Three stable hybridomas clones were selected and named 5D6, 7G3, and 8C9. The MAbs-based ELISA was scrutinized for species-specific recognition with a number of human throat swab samples from Group I (156 patients with typical respiratory illness clinically confirmed before) and Group II (57 healthy donors). Results In Group I, 55 positive cases were detected by anti-EB MAb-based ELISA, 51 cases were positive by MAbs 5D6-based ELISA, and 33 and 38 cases were positive by MAb 8C9 and 7G3-based ELISA respectively. Of the 57 samples from Group II "healthy donors", 5 were positive and 52 were negative with both anti-EB and 5D6-based tests, while 2 and 3 positive cases were identified by the other two MAb-based ELISAs respectively. Conclusion The novel MOMPvD2.VD3 MAb-based assay may have higher specificity than the anti-EB MAb, which may possibly be used as an alternative tool for the diagnosis of C. pneumoniae infection.
文摘The ultimate goal in phosphoinositides cellular metabolism is to decipher their global functional organization and coordination of the com- partmentalized signaling processes. In this report we present evidence linking nuclear phos- phoinositides cycle with endoplasmic reticulum synthesis and function. The rapid transformation of [3H]inositol-labeled phosphoinositides in the intact nuclei (IN) was captured in chase studies for 0-5 min, followed by examination of phosphatidylinositides in the inner nuclear me- mbrane (INM), the outer nuclear membrane (ONM) and endoplasmic reticulum (ER). We revealed that synthesis of phosphatidylinositol phosphates (PIPs) occurs in ONM and the de- phosphorylation takes place in the INM. The rapid transformation of the radiolabeled PIPs in ONM reverberated in their appearance and successive transformation in INM, and in the 5min chased nuclei was tracked to ONM as the re- emerging radiolabeled phosphatidylinositol (PI). These chase-uncovered changes in ONM and INM PIPs profiles allow us to conclude that the observed conversions in the nuclear membrane continuum are induced by the lateral movement of the membrane and its transit from the cytosolic to nuclear and back to cytosolic environment. The suggested membrane synthesisinduced movement provides the means to transport the membrane- and the membrane lipid ligand-associated cytosolic proteins to the intranuclear spaces and renewal of INM. Export of the nuclear components interacting with the modified INM, by exiting from nuclear to cytosolic site, endows ER with a steady influx of the membrane that is conditioned to generate vesicles according to the nucleus delivered templates.
基金This work was financially supported by National Key R&D Program of China(2022YFD1401200)China Agriculture Research System of MOF and MARA(CARS-24-C-04)+3 种基金National Natural Science Foundation of China(32270294)Ningbo Major Special Projects of the Plan‘Science and Technology Innovation 2025’(2021Z106)the Postdoctoral Science Foundation of Anhui Province,China(2021B558)K.C.Wong Magna Fund in Ningbo University.
文摘Pepper mild mottle virus(PMMoV)is a devastating viral pathogen of pepper(Capsicum annuum)but it is unclear whether and how peppers protect against PMMoV infection.The expression of the chloroplast outer membrane protein 24(OMP24)of C.annuum was upregulated under PMMoV infection and it interacted with PMMoV coat protein(CP).Silencing of OMP24 in either C.annuum or Nicotiana benthamiana facilitated PMMoV infection,whereas overexpression of N.benthamiana OMP24 in transgenic plants inhibited PMMoV infection.Both C.annuum OMP24(CaOMP24)and N.benthamiana OMP24(NbOMP24)localized to the chloroplast and have a moderately hydrophobic transmembrane domain that is necessary for their localization.Overexpression of CaOMP24 induced stromules,perinuclear chloroplast clustering,and accumulation of reactive oxygen species(ROS),the typical defense responses of chloroplasts transferring the retrograde signaling to the nucleus to regulate resistance genes.The expression of PR1 and PR2 was also upregulated significantly in plants overexpressing OMP24.Self-interaction of OMP24 was demonstrated and was required for OMP24-mediated plant defense.Interaction with PMMoV CP interfered with the self-interaction of OMP24 and impaired OMP24-induced stromules,perinuclear chloroplast clustering and ROS accumulation.The results demonstrate the defense function of OMP24 in pepper during viral infection and suggest a possible mechanism by which PMMoV CP modulates the plant defense to facilitate viral infection.
基金the National Natural Science Foundation of China(31072151)the Specialized Research Fund for the Doctoral Program of Higher Education,China(20090097110007)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China(PAPD)
文摘Aeromonas hydrophila isolates from clinical cases (n=43) were tested against 8 antimicrobial agents and typed by outer membrane protein (OMP) pattern by using sodium dodecyl sulfate gel electrophoresis. All isolates were resistant to ampicillin (MICs, ≥16 μg mL-1) and sulfamonomethoxine (MICs≥64 μg mLl), but susceptible to norfloxacin (MICs,≤0.5 μg mL-1). There was a high incidence of resistance to erythromycin (90.70%) and tylosin (93.02%), while a low incidences of resistance to ciprofloxacin (2.33%), enrofloxacin (2.33%) and florfenicol (4.65%). Six different outer membrane protein patterns were found among 34 isolates by analyzing proteins in the range of 22 to 50 kDa, other than 9 isolates with their respective profiles. The strains with the similar OMP profiles had similar resistances. Compared with the other strains from the same OMP patterns, NB-1, A.Pun and MR-1 had lacked the proteins in the range of 30 to 45 kDa and their resistance to florfenicol substantially increased. It is speculated that the outer membrane protein changes might correlate with decreased susceptibility to florfenicol in the three strains. Some strains which showed completely identical OMP types had a little difference in their resistance to fluoroquinolones, indicating that there might be other factors that were involved in the antimicrobial resistance of A. hydrophila.
基金supported by the National Science Foundation (No. 1248553)
文摘The amount of literature on both melting and thermal conductivity of iron at Earth’s core conditions is overwhelming and the discrepancies are very large.There is a broad range of experimental techniques each of which is flawed to a certain degree,which may explain the discrepancy.In this report,we present new data using a different method for determining the phase behavior and resistivity of iron in the laser-heated diamond cell by measuring the electrical resistance of both solid and liquid iron wires.The experiment avoids some of the major flaws of previous experiments,the most important of which is the detection of the onset of melting.These measurements confirm a shallow melting curve found earlier and the resistivity data imply a trend towards low thermal conductivity in the liquid outer core.
文摘The elasto-gravitational deformation response of the Earths solid parts to the perturbations of the pressure and gravity on the core-mantle boundary (CMB) and the solid inner core boundary (ICB), due to the dynamical behaviors of the fluid outer core (FOC), is discussed. The internal load Love numbers, which are formulized in a general form in this study, are employed to describe the Earths deformation. The preliminary reference Earth model (PREM) is used as an example to calculate the internal load Love numbers on the Earths surface, CMB and ICB, respectively. The characteristics of the Earths deformation variation with the depth and the perturbation periods on the boundaries of the FOC are also investigated. The numerical results indicate that the internal load Love numbers decrease quickly with the increasing degree of the spherical harmonics of the displacement and depend strongly on the perturbation frequencies, especially on the high frequencies. The results, obtained in this work, can be used to construct the boundary conditions for the core dynamics of the long-period oscillations of the Earths fluid outer core.