Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging ...Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a satellite.By performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of Earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic field.In all cases,magnetic reconnection occurs at low latitude magnetopause.The soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the magnetosheath.Local X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray images.Moreover,the magnetopause boundary can be identified using multiple viewing geometries.We also find that solar wind conditions have little effect on the magnetopause identification.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered.展开更多
Fermentation substrates of rice with different milling degrees(MDs) were prepared and fermented with human feces to compare their fermentation properties and effects on gut microbiota.MD 0s,MD 5s and MD 60s represente...Fermentation substrates of rice with different milling degrees(MDs) were prepared and fermented with human feces to compare their fermentation properties and effects on gut microbiota.MD 0s,MD 5s and MD 60s represented brown rice,moderately-milled rice and white rice,respectively.After in vitro fermentation,the MD 5s group showed higher starch utilization,compared with the MD 0s and 60s groups evaluated by Fourier transform infrared spectrometer,and confocal laser scanning microscope.Effects of fermentation substrates of rice with different MDs on gut microbiota were evaluated by 16S rDNA sequencing.All the sample groups reduced the pH and produced short-chain fatty acids(SCFAs) and branched-chain fatty acids.The MD 5s group exhibited higher α-diversity than the MD 0s and 60s groups.Abundances of Phascolarctobacterium,Blautia and norank_f_Ruminococcaceae were higher in the MD 0s and 5s groups,compared with the MD 60s group.These bacteria were also positively correlated with the SCFAs production via Spearman correlation analysis.In vitro culture assay revealed that fermentation substrates of MD 0s and 5s promoted the growth of two probiotics(Akkermansia muciniphila and Bifidobacterium adolescentis).Our results showed that moderate milling might be an appropriate way to produce rice products with richer nutrients and better fermentation properties.展开更多
The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive ut...The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive utilization of the heterointerface effect can endow the catalysts with remarkably boosted electrocatalytic performance due to the modified electronic state of active sites.Herein,we demonstrate deliberate crafting of CoP/CoO heterojunction porous nanotubes(abbreviated as CoP/CoO PNTs hereafter)using a self-sacrificial template-engaged strategy.Precise control over the Kirkendall diffusion process of the presynthesized cobalt–aspartic acid complex nanowires is indispensable for the formation of CoP/CoO heterostructures.The topochemical transformation strategy of the reactive templates enables uniform and maximized construction of CoP/CoO heterojunctions throughout all the porous nanotubes.The establishment of CoP/CoO heterojunctions could considerably modify the electronic configuration of the active sites and also improve the electric conductivity,which endows the resultant CoP/CoO PNTs with enhanced intrinsic activity.Simultaneously,the hollow and porous nanotube architectures allow sufficient accessibility of exterior/interior surfaces and molecular permeability,drastically promoting the reaction kinetics.Consequently,when used as HER electrocatalysts,the well-designed CoP/CoO PNTs show Pt-like activity,with an overpotential of only 61 mV at 10mA cm^(−2) and excellent stability in 1.0M KOH medium,exceeding those of the vast majority of the previously reported nonprecious candidates.Density functional theory calculations further substantiate that the construction of CoP/CoO heterojunctions enables optimization of the Gibbs free energies for water adsorption and H adsorption,resulting in boosted HER intrinsic activity.The present study may provide in-depth insights into the fundamental mechanisms of heterojunction-induced electronic regulation,which may pave the way for the rational design of advanced Earth-abundant electrocatalysts in the future.展开更多
BACKGROUND After receiving entecavir or combined with FuzhengHuayu tablet(FZHY)treatment,some sufferers with hepatitis B virus(HBV)-related liver fibrosis could achieve a histological improvement while the others may ...BACKGROUND After receiving entecavir or combined with FuzhengHuayu tablet(FZHY)treatment,some sufferers with hepatitis B virus(HBV)-related liver fibrosis could achieve a histological improvement while the others may fail to improve even worsen.Serum metabolomics at baseline in these patients who were effective in treatment remain unclear.AIM To explore baseline serum metabolites characteristics in responders.METHODS A total of 132 patients with HBV-related liver fibrosis and 18 volunteers as healthy controls were recruited.First,all subjects were divided into training set and validation set.Second,the included patients were subdivided into entecavir responders(E-R),entecavir no-responders(E-N),FZHY+entecavir responders(FR),and FZHY+entecavir no-responders(F-N)following the pathological histological changes after 48 wk’treatments.Then,Serum samples of all subjects before treatment were tested by high performance liquid chromatographytandem mass spectrometry(LC-MS)high-performance LC-MS.Data processing was conducted using multivariate principal component analysis and orthogonal partial least squares discriminant analysis.Diagnostic tests of selected differential metabolites were used for Boruta analyses and logistic regression.RESULTS As for the intersection about differential metabolic pathways between the groups E-R vs E-N and F-R vs F-N,results showed that 4 pathways including linoleic acid metabolism,aminoacyl-tRNA biosynthesis,cyanoamino acid metabolism,alanine,aspartate and glutamate metabolism were screened out.As for the differential metabolites,these 7 intersected metabolites including hydroxypropionic acid,tyrosine,citric acid,taurochenodeoxycholic acid,benzoic acid,2-Furoic acid,and propionic acid were selected.CONCLUSION Our findings showed that 4 metabolic pathways and 7 differential metabolites had potential usefulness in clinical prediction of the response of entecavir or combined with FZHY on HBV fibrotic liver.展开更多
The hydrogen evolution reaction performance of semiconducting 2H-phase molybdenum disulfide(2H-MoS_(2))presents a significant hurdle in realizing its full potential applications.Here,we utilize theoretical calculation...The hydrogen evolution reaction performance of semiconducting 2H-phase molybdenum disulfide(2H-MoS_(2))presents a significant hurdle in realizing its full potential applications.Here,we utilize theoretical calculations to predict possible functionalized graphene quantum dots(GQDs),which can enhance HER activity of bulk MoS_(2).Subsequently,we design a functionalized GQD-induced in-situ bottom-up strategy to fabricate near atom-layer 2H-MoS_(2) nanosheets mediated with GQDs(ALQD)by modulating the concentration of electron withdrawing/donating functional groups.Experimental results reveal that the introduction of a series of functionalized GQDs during the synthesis of ALQD plays a crucial role.Notably,the higher the concentration and strength of electron-withdrawing functional groups on GQDs,the thinner and more active the resulting ALQD are.Remarkably,the synthesized near atom-layer ALQD-SO_(3)demonstrate significantly improved HER performance.Our GQD-induced strategy provides a simple and efficient approach for expanding the catalytic application of MoS_(2).Furthermore,it holds substantial potential for developing nanosheets in other transition-metal dichalcogenide materials.展开更多
Railway turnout is one of the critical equipment of Switch&Crossing(S&C)Systems in railway,related to the train’s safety and operation efficiency.With the advancement of intelligent sensors,data-driven fault ...Railway turnout is one of the critical equipment of Switch&Crossing(S&C)Systems in railway,related to the train’s safety and operation efficiency.With the advancement of intelligent sensors,data-driven fault detection technology for railway turnout has become an important research topic.However,little research in the literature has investigated the capability of data-driven fault detection technology for metro railway turnout.This paper presents a convolutional autoencoder-based fault detection method for the metro railway turnout considering human field inspection scenarios.First,the one-dimensional original time-series signal is converted into a twodimensional image by data pre-processing and 2D representation.Next,a binary classification model based on the convolutional autoencoder is developed to implement fault detection.The profile and structure information can be captured by processing data as images.The performance of our method is evaluated and tested on real-world operational current data in themetro stations.Experimental results show that the proposedmethod achieves better performance,especially in terms of error rate and specificity,and is robust in practical engineering applications.展开更多
To derive meaningful navigation strategies,animals have to estimate their directional headings in the environment.Accordingly,this function is achieved by the head direction cells that were found in mammalian brains,w...To derive meaningful navigation strategies,animals have to estimate their directional headings in the environment.Accordingly,this function is achieved by the head direction cells that were found in mammalian brains,whose neural activities encode one’s heading direction.It is believed that such head direction information is generated by integrating self-motion cues,which also introduces accumulative errors in the long term.To eliminate such errors,this paper presents an efficient calibration model that mimics the animals’behavior by exploiting visual cues in a biologically plausible way,and then implements it in robotic navigation tasks.The proposed calibration model allows the agent to associate its head direction and the perceived egocentric direction of a visual cue with its position and orientation,and therefore to calibrate the head direction when the same cue is viewed again.We examine the proposed head direction calibration model in extensive simulations and real-world experiments and demonstrate its excellent performance in terms of quick association of information to proximal or distal cues as well as accuracy of calibrating the integration errors of the head direction.Videos can be viewed at https://videoviewsite.wixsite.com/hdc-calibration.展开更多
Monodispersed copper oxalate particles with flaky morphology were prepared via a simple one-pot synthesis method. Scanning electron microscope(SEM), X-ray diffraction(XRD), and fourier transform infrared(FTIR) spectra...Monodispersed copper oxalate particles with flaky morphology were prepared via a simple one-pot synthesis method. Scanning electron microscope(SEM), X-ray diffraction(XRD), and fourier transform infrared(FTIR) spectra were used to characterize particle morphology, size, phase composition, and functional groups. It was found that the presence of ethylenediaminetetraacetic acid(EDTA) and the solution p H value had strong influence on the morphological and size evolution of the precipitated particles. On the basis of controlled release of copper ions from a Cu2+–EDTA complex and Weimarn's law, a strategy for the controlled synthesis of monodispersed copper oxalate particles was designed by referring to the basic mode of the St?ber method. The inherent nature of crystallization to form the flaky solid in the early stage of precipitation as well as the driving force of the long-lasting low supersaturation in the growth stage was proposed to explain the size and morphological evolution of the copper oxalate precipitates. Thermodynamic equilibrium concentrations of copper(II) species in the Cu(II)–EDTA–oxalate–H2 O solution system were calculated to help explain the possible formation mechanism of copper oxalate precipitates.展开更多
氧电催化一般涉及到氧还原反应(ORR)和氧析出应(OER),是诸如燃料电池,金属空气电池和水电解池等能源转换与存储技术的关键步骤.其中,可充电的金属锌空气电池具有较高的能量密度,开发成本较低,运行安全且环境友好.然而,开发并采用高效,...氧电催化一般涉及到氧还原反应(ORR)和氧析出应(OER),是诸如燃料电池,金属空气电池和水电解池等能源转换与存储技术的关键步骤.其中,可充电的金属锌空气电池具有较高的能量密度,开发成本较低,运行安全且环境友好.然而,开发并采用高效,低成本且储量丰富的催化材料代替贵金属基电催化剂,仍旧是现阶段尚未完全解决的问题和挑战.最近,金属有机框架(MOFs)以及碳基的金属有机框架衍生物作为高效电催化剂,因其超乎寻常的形貌,结构,组分和功能性的可调节能力,已经逐渐引起了广泛的关注和研究兴趣.因此,本文报道了一种泡沫镍负载的二维金属有机框架及其衍生物耦合阵列作为无粘结剂型ORR/OER双效催化剂,能够实现高比表面积,高电导率和高双功能性,同时避免了使用有机粘结剂的复杂制备过程和不可避免的电池性能影响.与传统设计不同,本文主要通过集成各司其职的不同功能组分并充分暴露电化学活性面积来提高双效电极的整体活性.电化学测试结果表明,耦合阵列电极(R-NCM)相比于MOFs阵列(NCM)和MOFs衍生物阵列(A-NCM)等对比电极,具有显著提高的双效氧电极性能,氧还原反应的起峰电位约为0.90 V,而氧析出反应电流密度达到100 m Acm-2时的过电势为319 m V.由于其在生长–热裂解–再生长过程中所具有的稳定的站立多级二维纳米片结构,所制备的双效氧电极材料表现出显著增强的双官能团性,电化学活性面积,反应动力学和稳定性,并可进一步用于可充电的金属锌空气电池(ZABs).考虑到制备过程的可行性与简洁性,所提出的生长–热裂解–再生长策略不仅能够用于耦合型分级纳米片阵列结构的合成,还能为设计开发相关能源电化学装置的高活性电极结构提供借鉴.展开更多
Diabetic osteoporosis(DOP) is the leading complication continuously threatening the bone health of patients with diabetes. A key pathogenic factor in DOP is loss of osteocyte viability. However, the mechanism of osteo...Diabetic osteoporosis(DOP) is the leading complication continuously threatening the bone health of patients with diabetes. A key pathogenic factor in DOP is loss of osteocyte viability. However, the mechanism of osteocyte death remains unclear. Here, we identified ferroptosis, which is iron-dependent programmed cell death, as a critical mechanism of osteocyte death in murine models of DOP. The diabetic microenvironment significantly enhanced osteocyte ferroptosis in vitro, as shown by the substantial lipid peroxidation, iron overload, and aberrant activation of the ferroptosis pathway. RNA sequencing showed that heme oxygenase-1(HO-1) expression was notably upregulated in ferroptotic osteocytes. Further findings revealed that HO-1 was essential for osteocyte ferroptosis in DOP and that its promoter activity was controlled by the interaction between the upstream NRF2 and c-JUN transcription factors. Targeting ferroptosis or HO-1 efficiently rescued osteocyte death in DOP by disrupting the vicious cycle between lipid peroxidation and HO-1 activation, eventually ameliorating trabecular deterioration. Our study provides insight into DOP pathogenesis, and our results provide a mechanism-based strategy for clinical DOP treatment.展开更多
With the deep combination of both modern information technology and traditional agriculture,the era of agriculture 4.0,which takes the form of smart agriculture,has come.Smart agriculture provides solutions for agricu...With the deep combination of both modern information technology and traditional agriculture,the era of agriculture 4.0,which takes the form of smart agriculture,has come.Smart agriculture provides solutions for agricultural intelligence and automation.However,information security issues cannot be ignored with the development of agriculture brought by modern information technology.In this paper,three typical development modes of smart agriculture(precision agriculture,facility agriculture,and order agriculture)are presented.Then,7 key technologies and 11 key applications are derived from the above modes.Based on the above technologies and applications,6 security and privacy countermeasures(authentication and access control,privacy-preserving,blockchain-based solutions for data integrity,cryptography and key management,physical countermeasures,and intrusion detection systems)are summarized and discussed.Moreover,the security challenges of smart agriculture are analyzed and organized into two aspects:1)agricultural production,and 2)information technology.Most current research projects have not taken agricultural equipment as potential security threats.Therefore,we did some additional experiments based on solar insecticidal lamps Internet of Things,and the results indicate that agricultural equipment has an impact on agricultural security.Finally,more technologies(5 G communication,fog computing,Internet of Everything,renewable energy management system,software defined network,virtual reality,augmented reality,and cyber security datasets for smart agriculture)are described as the future research directions of smart agriculture.展开更多
The water-cooled ceramic breeder (WCCB) blanket is one of the blanket candidates for Chinese fusion engineering testing reactor (CFETR) and is being developed at the Institute of Plasma Physics, Chinese Academy of Sci...The water-cooled ceramic breeder (WCCB) blanket is one of the blanket candidates for Chinese fusion engineering testing reactor (CFETR) and is being developed at the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). This paper reviews design and evolution of the WCCB blanket for CFETR, and presents a new WCCB blanket design according to the latest CFETR core parameters (major and minor radii are R = 7.2 m and a = 2.2 m, respectively) and missions. This new design is expected to satisfy multiple CFETR operation modes of 0.2, 0.5, 1.0, and 1.5 GW fusion power and achieve tritium self-sufficiency. The feasibility of the updated blanket design is evaluated from the aspects of neutronics and thermo-hydraulics. Furthermore, the research and development (R&D) activities supporting to the WCCB blanket for CFETR are reported, including the design code, the water loop experiments, the pebble bed modeling and experiments, and the components fabrication technology.展开更多
Objective:Homeobox B9(HOXB9) is proposed to be involved in tumor angiogenesis and metastasis.We investigated the role of HOXB9 in the progression of colon cancer.Methods:HOXB9 expression was investigated by immunohist...Objective:Homeobox B9(HOXB9) is proposed to be involved in tumor angiogenesis and metastasis.We investigated the role of HOXB9 in the progression of colon cancer.Methods:HOXB9 expression was investigated by immunohistochemically and Western blotting in 128 colon cancer patients and the results were analyzed statistically associated with clinicopathological data and survival of the patients.The effect of HOXB9 on cell invasion and metastases abilities were analyzed in vitro and in vivo.Results:HOXB9 is overexpressed in colon cancer tissues and significantly correlated with metastasis and poor survival of patients(P<0.05,respectively).Additionally,high levels of expression of HOXB9 were observed in metastatic lymph nodes.The down-regulation of HOXB9 expression can inhibit the migration and invasive ability of colon cancer cells,while exogenous expression of HOXB9 in colon cancer cells enhanced cell migration and invasiveness.Moreover,stable knockdown of HOXB9 reduced the liver and lung metastasis of colon cancer in vivo.Conclusions:HOXB9 may play an important role in the invasion and metastasis of colon cancer cells and may be a useful biomarker for metastasis and prognostic of colon cancer.展开更多
BACKGROUND Arthroscopic debridement is a mature treatment for knee osteoarthritis(KOA).Due to the differences in the research subjects,methods,and efficacy evaluation indexes,there are great differences in the surgica...BACKGROUND Arthroscopic debridement is a mature treatment for knee osteoarthritis(KOA).Due to the differences in the research subjects,methods,and efficacy evaluation indexes,there are great differences in the surgical efficacy reported in the literature.AIM To compare the medium-term efficacy of arthroscopic debridement and conservative treatment for KOA of Kellgren-Lawrence grades I-III.METHODS Patients with KOA of Kellgren-Lawrence grades I-III who were admitted to the orthopedic clinic of our hospital from July 2018 to December 2018 and agreed to undergo arthroscopic surgery were included in an arthroscopic debridement group,and those who refused surgical treatment were included in a conservative treatment group.Gender,age,body mass index(BMI),side of KOA,American hospital for special surgery knee score(HSS score)before treatment,visual analogue scale(VAS)score during walking and rest before treatment,conservative treatment content,and surgical procedure were recorded.Outpatient visits were conducted at the 1st,3rd,6th,12th,and 24th mo after treatment in the two groups.The changes of HSS score and VAS score in each group before and after treatment were statistically analyzed,and the differences of HSS score and VAS score in different treatment stages between the two groups were also compared.RESULTS In the conservative treatment group,there were 80 patients with complete followup data,including 20 males and 60 females,aged 58.75±14.66 years old.And in the knee arthroscopic debridement group,there were 98 patients with complete follow-up data,including 24 males and 74 females,aged 59.27±14.48 years old.There was no statistically significant difference in the general data(gender,age,BMI,side of KOA,Kellgren-Lawrence grade distribution,HSS score,and VAS score)between the two groups before treatment.The HSS scores of the conservative treatment group at the 1st,3rd,6th,12th,and 24th mo after treatment were significantly higher than that before treatment(P<0.05).There was no statistical difference in HSS score of the conservative treatment group among the 1st,3rd,6th,12th,and 24th mo(P>0.05).The HSS score of the knee arthroscopic debridement group at the 1st mo after surgery was significantly higher than that before surgery(P<0.05).HSS scores of the knee arthroscopic debridement group at the 3rd,6th,12th,and 24th mo were significantly higher than those before surgery and at the 1st mo after surgery(P<0.05).There were no statistically significant differences in HSS scores at the 3rd,6th,12th,and 24th mo after surgery(P>0.05).HSS scores at the 3rd,6th,12th,and 24th mo were significantly higher in the arthroscopic debridement group than in the conservative treatment group(P<0.05).There was no statistical difference in HSS scores between the two groups before treatment and at the 1st mo of follow-up(P>0.05).VAS scores during walking and rest were significantly decreased in both groups,and the VAS score during rest was significantly lower in the arthroscopic debridement group than in the conservative treatment group,but there was no significant difference in the VAS score during walking between the two groups after treatment.CONCLUSION Compared with conservative treatment,arthroscopic debridement can significantly improve the knee resting pain and knee functional status of patients with KOA of Kellgren-Lawrence grades I-III within 2 years after treatment.展开更多
Antimicrobial peptides(AMPs) are a group of gene-encoded small peptides that play pivotal roles in the host immune system of multicellular organisms.Cathelicidins are an important family of AMPs that exclusively exist...Antimicrobial peptides(AMPs) are a group of gene-encoded small peptides that play pivotal roles in the host immune system of multicellular organisms.Cathelicidins are an important family of AMPs that exclusively exist in vertebrates. Many cathelicidins have been identified from mammals, birds, reptiles and fish. To date, however, cathelicidins from amphibians are poorly understood. In the present study, two novel cathelicidins(OL-CATH1 and 2) were identified and studied from the odorous frog Odorrana livida.Firstly, the cDNAs encoding the OL-CATHs(780 and735 bp in length, respectively) were successfully cloned from a lung cDNA library constructed for the frog. Multi-sequence alignment was carried out to analyze differences between the precursors of the OL-CATHs and other representative cathelicidins.Mature peptide sequences of OL-CATH1 and 2 were predicted(33 amino acid residues) and their secondary structures were determined(OL-CATH1 showed a random-coil conformation and OL-CATH2 demonstrated α-helical conformation). Furthermore,OL-CATH1 and 2 were chemically synthesized and their in vitro functions were determined. Antimicrobial and bacterial killing kinetic analyses indicated that OL-CATH2 demonstrated relatively moderate and rapid antimicrobial potency and exhibited strong anti-inflammatory activity. At very low concentrations(10 μg/mL), OL-CATH2 significantly inhibited the lipopolysaccharide(LPS)-induced transcription and production of pro-inflammatory cytokines TNF-α, IL-1βand IL-6 in mouse peritoneal macrophages. In contrast, OL-CATH1 did not exhibit any detectableantimicrobial or anti-inflammatory activities. Overall,identification of these OL-CATHs from O. livida enriches our understanding of the functions of cathelicidins in the amphibian immune system. The potent antimicrobial and anti-inflammatory activities of OL-CATH2 highlight its potential as a novel candidate in anti-infective drug development.展开更多
Previous studies have reported that non-human primates and rodents exposed to lead during brain development may become dependent on the deposition of pre-determined β-amyloid protein (Aβ),and exhibit upregulation of...Previous studies have reported that non-human primates and rodents exposed to lead during brain development may become dependent on the deposition of pre-determined β-amyloid protein (Aβ),and exhibit upregulation of β-site amyloid precursor protein expression in old age.However,further evidence is required to elucidate the precise relationship and molecular mechanisms underlying the effects of early lead exposure on excessive Aβ production in adult mammals.The present study investigated the effects of lead exposure on expression of β-amyloid precursor protein cleavage enzyme-1 (BACE-1) in the rat retina and the production of Aβ in early development,using the retina as a window for studying Alzheimer's disease.Adult rats were intraocularly injected with different doses of lead acetate (10μmol/L,100μmol/L,1 mmol/L,10 mmol/L and 100 mmol/L).The results revealed that retinal lead concentration,BACE-1 and its cleavage products β-C-terminal fragment and retina Aβ1-40 were all significantly increased in almost all of the lead exposure groups 48 hours later in a dose-dependent manner.The only exception was the 10μmol/L group.The distribution of BACE-1 in the retina did not exhibit obvious changes,and no distinctive increase in the activation of retinal microglia was apparent.Similarly,retinal synaptophysin expression did not exhibit any clear changes.These data suggest that lead exposure can result in the upregulation of retinal neuron BACE-1 expression in the early period of development and further increase the overproduction of Aβ1-40 in the retina.Our results provided novel insight into the molecular mechanisms underlying environmentally-induced Alzheimer's disease.展开更多
基金supported by the National Natural Science Foundation of China(NNSFC)grants 42074202,42274196Strategic Priority Research Program of Chinese Academy of Sciences grant XDB41000000ISSI-BJ International Team Interaction between magnetic reconnection and turbulence:From the Sun to the Earth。
文摘Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a satellite.By performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of Earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic field.In all cases,magnetic reconnection occurs at low latitude magnetopause.The soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the magnetosheath.Local X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray images.Moreover,the magnetopause boundary can be identified using multiple viewing geometries.We also find that solar wind conditions have little effect on the magnetopause identification.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered.
基金supported by the National Natural Science Foundation of China (32202051)the Shanghai Sailing Program (21YF1431800, 20YF1433400)+1 种基金Shanghai Agriculture Applied Technology Development Program, China (2021-02-08-0012-F00780 )the National Key R&D Program of China (2022YFF1100104, 2023YFF1103404)。
文摘Fermentation substrates of rice with different milling degrees(MDs) were prepared and fermented with human feces to compare their fermentation properties and effects on gut microbiota.MD 0s,MD 5s and MD 60s represented brown rice,moderately-milled rice and white rice,respectively.After in vitro fermentation,the MD 5s group showed higher starch utilization,compared with the MD 0s and 60s groups evaluated by Fourier transform infrared spectrometer,and confocal laser scanning microscope.Effects of fermentation substrates of rice with different MDs on gut microbiota were evaluated by 16S rDNA sequencing.All the sample groups reduced the pH and produced short-chain fatty acids(SCFAs) and branched-chain fatty acids.The MD 5s group exhibited higher α-diversity than the MD 0s and 60s groups.Abundances of Phascolarctobacterium,Blautia and norank_f_Ruminococcaceae were higher in the MD 0s and 5s groups,compared with the MD 60s group.These bacteria were also positively correlated with the SCFAs production via Spearman correlation analysis.In vitro culture assay revealed that fermentation substrates of MD 0s and 5s promoted the growth of two probiotics(Akkermansia muciniphila and Bifidobacterium adolescentis).Our results showed that moderate milling might be an appropriate way to produce rice products with richer nutrients and better fermentation properties.
基金supported by the National Natural Science Foundation of China(Grant Nos.21972068,21875112,and 22075290)the Nanjing IPE Institute of Green Manufacturing Industrythe Beijing Natural Science Foundation(Grant No.Z200012).
文摘The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive utilization of the heterointerface effect can endow the catalysts with remarkably boosted electrocatalytic performance due to the modified electronic state of active sites.Herein,we demonstrate deliberate crafting of CoP/CoO heterojunction porous nanotubes(abbreviated as CoP/CoO PNTs hereafter)using a self-sacrificial template-engaged strategy.Precise control over the Kirkendall diffusion process of the presynthesized cobalt–aspartic acid complex nanowires is indispensable for the formation of CoP/CoO heterostructures.The topochemical transformation strategy of the reactive templates enables uniform and maximized construction of CoP/CoO heterojunctions throughout all the porous nanotubes.The establishment of CoP/CoO heterojunctions could considerably modify the electronic configuration of the active sites and also improve the electric conductivity,which endows the resultant CoP/CoO PNTs with enhanced intrinsic activity.Simultaneously,the hollow and porous nanotube architectures allow sufficient accessibility of exterior/interior surfaces and molecular permeability,drastically promoting the reaction kinetics.Consequently,when used as HER electrocatalysts,the well-designed CoP/CoO PNTs show Pt-like activity,with an overpotential of only 61 mV at 10mA cm^(−2) and excellent stability in 1.0M KOH medium,exceeding those of the vast majority of the previously reported nonprecious candidates.Density functional theory calculations further substantiate that the construction of CoP/CoO heterojunctions enables optimization of the Gibbs free energies for water adsorption and H adsorption,resulting in boosted HER intrinsic activity.The present study may provide in-depth insights into the fundamental mechanisms of heterojunction-induced electronic regulation,which may pave the way for the rational design of advanced Earth-abundant electrocatalysts in the future.
基金Supported by National Science and Technology Major Project,No.2014ZX10005001 and No.2018ZX10302204National Natural Science Foundation of China,No.81730109 and No.82274305+2 种基金Shanghai Key Specialty of Traditional Chinese Clinical Medicine,No.shslczdzk01201China Postdoctoral Science Foundation,No.2022M722162Siming Youth Fund of Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine,No.SGKJ-202104.
文摘BACKGROUND After receiving entecavir or combined with FuzhengHuayu tablet(FZHY)treatment,some sufferers with hepatitis B virus(HBV)-related liver fibrosis could achieve a histological improvement while the others may fail to improve even worsen.Serum metabolomics at baseline in these patients who were effective in treatment remain unclear.AIM To explore baseline serum metabolites characteristics in responders.METHODS A total of 132 patients with HBV-related liver fibrosis and 18 volunteers as healthy controls were recruited.First,all subjects were divided into training set and validation set.Second,the included patients were subdivided into entecavir responders(E-R),entecavir no-responders(E-N),FZHY+entecavir responders(FR),and FZHY+entecavir no-responders(F-N)following the pathological histological changes after 48 wk’treatments.Then,Serum samples of all subjects before treatment were tested by high performance liquid chromatographytandem mass spectrometry(LC-MS)high-performance LC-MS.Data processing was conducted using multivariate principal component analysis and orthogonal partial least squares discriminant analysis.Diagnostic tests of selected differential metabolites were used for Boruta analyses and logistic regression.RESULTS As for the intersection about differential metabolic pathways between the groups E-R vs E-N and F-R vs F-N,results showed that 4 pathways including linoleic acid metabolism,aminoacyl-tRNA biosynthesis,cyanoamino acid metabolism,alanine,aspartate and glutamate metabolism were screened out.As for the differential metabolites,these 7 intersected metabolites including hydroxypropionic acid,tyrosine,citric acid,taurochenodeoxycholic acid,benzoic acid,2-Furoic acid,and propionic acid were selected.CONCLUSION Our findings showed that 4 metabolic pathways and 7 differential metabolites had potential usefulness in clinical prediction of the response of entecavir or combined with FZHY on HBV fibrotic liver.
基金This research was supported by Shanghai Pujiang Program(21PJD022)National Natural Science Foundation of China(21901154).
文摘The hydrogen evolution reaction performance of semiconducting 2H-phase molybdenum disulfide(2H-MoS_(2))presents a significant hurdle in realizing its full potential applications.Here,we utilize theoretical calculations to predict possible functionalized graphene quantum dots(GQDs),which can enhance HER activity of bulk MoS_(2).Subsequently,we design a functionalized GQD-induced in-situ bottom-up strategy to fabricate near atom-layer 2H-MoS_(2) nanosheets mediated with GQDs(ALQD)by modulating the concentration of electron withdrawing/donating functional groups.Experimental results reveal that the introduction of a series of functionalized GQDs during the synthesis of ALQD plays a crucial role.Notably,the higher the concentration and strength of electron-withdrawing functional groups on GQDs,the thinner and more active the resulting ALQD are.Remarkably,the synthesized near atom-layer ALQD-SO_(3)demonstrate significantly improved HER performance.Our GQD-induced strategy provides a simple and efficient approach for expanding the catalytic application of MoS_(2).Furthermore,it holds substantial potential for developing nanosheets in other transition-metal dichalcogenide materials.
基金supported in part by the National Natural Science Foundation of China under Grant U1734211.
文摘Railway turnout is one of the critical equipment of Switch&Crossing(S&C)Systems in railway,related to the train’s safety and operation efficiency.With the advancement of intelligent sensors,data-driven fault detection technology for railway turnout has become an important research topic.However,little research in the literature has investigated the capability of data-driven fault detection technology for metro railway turnout.This paper presents a convolutional autoencoder-based fault detection method for the metro railway turnout considering human field inspection scenarios.First,the one-dimensional original time-series signal is converted into a twodimensional image by data pre-processing and 2D representation.Next,a binary classification model based on the convolutional autoencoder is developed to implement fault detection.The profile and structure information can be captured by processing data as images.The performance of our method is evaluated and tested on real-world operational current data in themetro stations.Experimental results show that the proposedmethod achieves better performance,especially in terms of error rate and specificity,and is robust in practical engineering applications.
基金funding from the European Union’s Horizon 2020 Framework Programme for Research and Innovation under the Specific Grant Agreement No.945539(Human Brain Project SGA3)also funded by Pazhou Lab PZL2021KF0020.
文摘To derive meaningful navigation strategies,animals have to estimate their directional headings in the environment.Accordingly,this function is achieved by the head direction cells that were found in mammalian brains,whose neural activities encode one’s heading direction.It is believed that such head direction information is generated by integrating self-motion cues,which also introduces accumulative errors in the long term.To eliminate such errors,this paper presents an efficient calibration model that mimics the animals’behavior by exploiting visual cues in a biologically plausible way,and then implements it in robotic navigation tasks.The proposed calibration model allows the agent to associate its head direction and the perceived egocentric direction of a visual cue with its position and orientation,and therefore to calibrate the head direction when the same cue is viewed again.We examine the proposed head direction calibration model in extensive simulations and real-world experiments and demonstrate its excellent performance in terms of quick association of information to proximal or distal cues as well as accuracy of calibrating the integration errors of the head direction.Videos can be viewed at https://videoviewsite.wixsite.com/hdc-calibration.
基金financially supported by the Special Fundamental Funds by Beijing Scientific Committee for the Project of New Functional Materials for Environmental Remediation(No.00012245)
文摘Monodispersed copper oxalate particles with flaky morphology were prepared via a simple one-pot synthesis method. Scanning electron microscope(SEM), X-ray diffraction(XRD), and fourier transform infrared(FTIR) spectra were used to characterize particle morphology, size, phase composition, and functional groups. It was found that the presence of ethylenediaminetetraacetic acid(EDTA) and the solution p H value had strong influence on the morphological and size evolution of the precipitated particles. On the basis of controlled release of copper ions from a Cu2+–EDTA complex and Weimarn's law, a strategy for the controlled synthesis of monodispersed copper oxalate particles was designed by referring to the basic mode of the St?ber method. The inherent nature of crystallization to form the flaky solid in the early stage of precipitation as well as the driving force of the long-lasting low supersaturation in the growth stage was proposed to explain the size and morphological evolution of the copper oxalate precipitates. Thermodynamic equilibrium concentrations of copper(II) species in the Cu(II)–EDTA–oxalate–H2 O solution system were calculated to help explain the possible formation mechanism of copper oxalate precipitates.
基金Project(51275132)supported by the National Natural Science Foundation of ChinaProject(2008RFQXG040)supported by the Youth Science and Technology Project of Harbin,China
文摘氧电催化一般涉及到氧还原反应(ORR)和氧析出应(OER),是诸如燃料电池,金属空气电池和水电解池等能源转换与存储技术的关键步骤.其中,可充电的金属锌空气电池具有较高的能量密度,开发成本较低,运行安全且环境友好.然而,开发并采用高效,低成本且储量丰富的催化材料代替贵金属基电催化剂,仍旧是现阶段尚未完全解决的问题和挑战.最近,金属有机框架(MOFs)以及碳基的金属有机框架衍生物作为高效电催化剂,因其超乎寻常的形貌,结构,组分和功能性的可调节能力,已经逐渐引起了广泛的关注和研究兴趣.因此,本文报道了一种泡沫镍负载的二维金属有机框架及其衍生物耦合阵列作为无粘结剂型ORR/OER双效催化剂,能够实现高比表面积,高电导率和高双功能性,同时避免了使用有机粘结剂的复杂制备过程和不可避免的电池性能影响.与传统设计不同,本文主要通过集成各司其职的不同功能组分并充分暴露电化学活性面积来提高双效电极的整体活性.电化学测试结果表明,耦合阵列电极(R-NCM)相比于MOFs阵列(NCM)和MOFs衍生物阵列(A-NCM)等对比电极,具有显著提高的双效氧电极性能,氧还原反应的起峰电位约为0.90 V,而氧析出反应电流密度达到100 m Acm-2时的过电势为319 m V.由于其在生长–热裂解–再生长过程中所具有的稳定的站立多级二维纳米片结构,所制备的双效氧电极材料表现出显著增强的双官能团性,电化学活性面积,反应动力学和稳定性,并可进一步用于可充电的金属锌空气电池(ZABs).考虑到制备过程的可行性与简洁性,所提出的生长–热裂解–再生长策略不仅能够用于耦合型分级纳米片阵列结构的合成,还能为设计开发相关能源电化学装置的高活性电极结构提供借鉴.
基金supported by National Natural Science Foundation of China(NSFC)grants 92068205,81802679,and 82002328supported by China Postdoctoral Science Foundation grants 2018M632136 and 2019T120348。
文摘Diabetic osteoporosis(DOP) is the leading complication continuously threatening the bone health of patients with diabetes. A key pathogenic factor in DOP is loss of osteocyte viability. However, the mechanism of osteocyte death remains unclear. Here, we identified ferroptosis, which is iron-dependent programmed cell death, as a critical mechanism of osteocyte death in murine models of DOP. The diabetic microenvironment significantly enhanced osteocyte ferroptosis in vitro, as shown by the substantial lipid peroxidation, iron overload, and aberrant activation of the ferroptosis pathway. RNA sequencing showed that heme oxygenase-1(HO-1) expression was notably upregulated in ferroptotic osteocytes. Further findings revealed that HO-1 was essential for osteocyte ferroptosis in DOP and that its promoter activity was controlled by the interaction between the upstream NRF2 and c-JUN transcription factors. Targeting ferroptosis or HO-1 efficiently rescued osteocyte death in DOP by disrupting the vicious cycle between lipid peroxidation and HO-1 activation, eventually ameliorating trabecular deterioration. Our study provides insight into DOP pathogenesis, and our results provide a mechanism-based strategy for clinical DOP treatment.
基金supported in part by the National Natural Science Foundation of China(62072248,61902188)in part by China Postdoctoral Science Foundation(2019M651713)。
文摘With the deep combination of both modern information technology and traditional agriculture,the era of agriculture 4.0,which takes the form of smart agriculture,has come.Smart agriculture provides solutions for agricultural intelligence and automation.However,information security issues cannot be ignored with the development of agriculture brought by modern information technology.In this paper,three typical development modes of smart agriculture(precision agriculture,facility agriculture,and order agriculture)are presented.Then,7 key technologies and 11 key applications are derived from the above modes.Based on the above technologies and applications,6 security and privacy countermeasures(authentication and access control,privacy-preserving,blockchain-based solutions for data integrity,cryptography and key management,physical countermeasures,and intrusion detection systems)are summarized and discussed.Moreover,the security challenges of smart agriculture are analyzed and organized into two aspects:1)agricultural production,and 2)information technology.Most current research projects have not taken agricultural equipment as potential security threats.Therefore,we did some additional experiments based on solar insecticidal lamps Internet of Things,and the results indicate that agricultural equipment has an impact on agricultural security.Finally,more technologies(5 G communication,fog computing,Internet of Everything,renewable energy management system,software defined network,virtual reality,augmented reality,and cyber security datasets for smart agriculture)are described as the future research directions of smart agriculture.
基金the financial support of the National Key R&D Program of China(Grants2017YFE0300503 and 2017YFE0300604)the National Natural Science Foundation of China(Grant 11775256)
文摘The water-cooled ceramic breeder (WCCB) blanket is one of the blanket candidates for Chinese fusion engineering testing reactor (CFETR) and is being developed at the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). This paper reviews design and evolution of the WCCB blanket for CFETR, and presents a new WCCB blanket design according to the latest CFETR core parameters (major and minor radii are R = 7.2 m and a = 2.2 m, respectively) and missions. This new design is expected to satisfy multiple CFETR operation modes of 0.2, 0.5, 1.0, and 1.5 GW fusion power and achieve tritium self-sufficiency. The feasibility of the updated blanket design is evaluated from the aspects of neutronics and thermo-hydraulics. Furthermore, the research and development (R&D) activities supporting to the WCCB blanket for CFETR are reported, including the design code, the water loop experiments, the pebble bed modeling and experiments, and the components fabrication technology.
基金supported by grants from the National Natural Science Foundation of China(No.81060196)the Scientific Research Project Foundation of Jiangxi Provincial Education Department(No.GJJ11333)Jiangxi Provincial Major Disciplines of Academic and Technical Leaders Project(No.20113BCB22004)
文摘Objective:Homeobox B9(HOXB9) is proposed to be involved in tumor angiogenesis and metastasis.We investigated the role of HOXB9 in the progression of colon cancer.Methods:HOXB9 expression was investigated by immunohistochemically and Western blotting in 128 colon cancer patients and the results were analyzed statistically associated with clinicopathological data and survival of the patients.The effect of HOXB9 on cell invasion and metastases abilities were analyzed in vitro and in vivo.Results:HOXB9 is overexpressed in colon cancer tissues and significantly correlated with metastasis and poor survival of patients(P<0.05,respectively).Additionally,high levels of expression of HOXB9 were observed in metastatic lymph nodes.The down-regulation of HOXB9 expression can inhibit the migration and invasive ability of colon cancer cells,while exogenous expression of HOXB9 in colon cancer cells enhanced cell migration and invasiveness.Moreover,stable knockdown of HOXB9 reduced the liver and lung metastasis of colon cancer in vivo.Conclusions:HOXB9 may play an important role in the invasion and metastasis of colon cancer cells and may be a useful biomarker for metastasis and prognostic of colon cancer.
基金Shanghai Jing'an District Health Research Project,China,No.2018MS09.
文摘BACKGROUND Arthroscopic debridement is a mature treatment for knee osteoarthritis(KOA).Due to the differences in the research subjects,methods,and efficacy evaluation indexes,there are great differences in the surgical efficacy reported in the literature.AIM To compare the medium-term efficacy of arthroscopic debridement and conservative treatment for KOA of Kellgren-Lawrence grades I-III.METHODS Patients with KOA of Kellgren-Lawrence grades I-III who were admitted to the orthopedic clinic of our hospital from July 2018 to December 2018 and agreed to undergo arthroscopic surgery were included in an arthroscopic debridement group,and those who refused surgical treatment were included in a conservative treatment group.Gender,age,body mass index(BMI),side of KOA,American hospital for special surgery knee score(HSS score)before treatment,visual analogue scale(VAS)score during walking and rest before treatment,conservative treatment content,and surgical procedure were recorded.Outpatient visits were conducted at the 1st,3rd,6th,12th,and 24th mo after treatment in the two groups.The changes of HSS score and VAS score in each group before and after treatment were statistically analyzed,and the differences of HSS score and VAS score in different treatment stages between the two groups were also compared.RESULTS In the conservative treatment group,there were 80 patients with complete followup data,including 20 males and 60 females,aged 58.75±14.66 years old.And in the knee arthroscopic debridement group,there were 98 patients with complete follow-up data,including 24 males and 74 females,aged 59.27±14.48 years old.There was no statistically significant difference in the general data(gender,age,BMI,side of KOA,Kellgren-Lawrence grade distribution,HSS score,and VAS score)between the two groups before treatment.The HSS scores of the conservative treatment group at the 1st,3rd,6th,12th,and 24th mo after treatment were significantly higher than that before treatment(P<0.05).There was no statistical difference in HSS score of the conservative treatment group among the 1st,3rd,6th,12th,and 24th mo(P>0.05).The HSS score of the knee arthroscopic debridement group at the 1st mo after surgery was significantly higher than that before surgery(P<0.05).HSS scores of the knee arthroscopic debridement group at the 3rd,6th,12th,and 24th mo were significantly higher than those before surgery and at the 1st mo after surgery(P<0.05).There were no statistically significant differences in HSS scores at the 3rd,6th,12th,and 24th mo after surgery(P>0.05).HSS scores at the 3rd,6th,12th,and 24th mo were significantly higher in the arthroscopic debridement group than in the conservative treatment group(P<0.05).There was no statistical difference in HSS scores between the two groups before treatment and at the 1st mo of follow-up(P>0.05).VAS scores during walking and rest were significantly decreased in both groups,and the VAS score during rest was significantly lower in the arthroscopic debridement group than in the conservative treatment group,but there was no significant difference in the VAS score during walking between the two groups after treatment.CONCLUSION Compared with conservative treatment,arthroscopic debridement can significantly improve the knee resting pain and knee functional status of patients with KOA of Kellgren-Lawrence grades I-III within 2 years after treatment.
基金supported by grants from the Jiangsu Students' Innovation and Entrepreneurship Training Program(2017suda098)the National Natural Science Foundation of China(31772455)+2 种基金Natural Science Foundation of Jiangsu Province(BK20160336 and BK20171214)Natural Science Foundation of College in Jiangsu Province(16KJB350004)Suzhou Science and Technology Development Project(SYN201504 and SNG2017045)
文摘Antimicrobial peptides(AMPs) are a group of gene-encoded small peptides that play pivotal roles in the host immune system of multicellular organisms.Cathelicidins are an important family of AMPs that exclusively exist in vertebrates. Many cathelicidins have been identified from mammals, birds, reptiles and fish. To date, however, cathelicidins from amphibians are poorly understood. In the present study, two novel cathelicidins(OL-CATH1 and 2) were identified and studied from the odorous frog Odorrana livida.Firstly, the cDNAs encoding the OL-CATHs(780 and735 bp in length, respectively) were successfully cloned from a lung cDNA library constructed for the frog. Multi-sequence alignment was carried out to analyze differences between the precursors of the OL-CATHs and other representative cathelicidins.Mature peptide sequences of OL-CATH1 and 2 were predicted(33 amino acid residues) and their secondary structures were determined(OL-CATH1 showed a random-coil conformation and OL-CATH2 demonstrated α-helical conformation). Furthermore,OL-CATH1 and 2 were chemically synthesized and their in vitro functions were determined. Antimicrobial and bacterial killing kinetic analyses indicated that OL-CATH2 demonstrated relatively moderate and rapid antimicrobial potency and exhibited strong anti-inflammatory activity. At very low concentrations(10 μg/mL), OL-CATH2 significantly inhibited the lipopolysaccharide(LPS)-induced transcription and production of pro-inflammatory cytokines TNF-α, IL-1βand IL-6 in mouse peritoneal macrophages. In contrast, OL-CATH1 did not exhibit any detectableantimicrobial or anti-inflammatory activities. Overall,identification of these OL-CATHs from O. livida enriches our understanding of the functions of cathelicidins in the amphibian immune system. The potent antimicrobial and anti-inflammatory activities of OL-CATH2 highlight its potential as a novel candidate in anti-infective drug development.
基金the National Natural Science Foundation of China,No.30900773the National University Basic Research Foundation of China,No.2010QZZD022
文摘Previous studies have reported that non-human primates and rodents exposed to lead during brain development may become dependent on the deposition of pre-determined β-amyloid protein (Aβ),and exhibit upregulation of β-site amyloid precursor protein expression in old age.However,further evidence is required to elucidate the precise relationship and molecular mechanisms underlying the effects of early lead exposure on excessive Aβ production in adult mammals.The present study investigated the effects of lead exposure on expression of β-amyloid precursor protein cleavage enzyme-1 (BACE-1) in the rat retina and the production of Aβ in early development,using the retina as a window for studying Alzheimer's disease.Adult rats were intraocularly injected with different doses of lead acetate (10μmol/L,100μmol/L,1 mmol/L,10 mmol/L and 100 mmol/L).The results revealed that retinal lead concentration,BACE-1 and its cleavage products β-C-terminal fragment and retina Aβ1-40 were all significantly increased in almost all of the lead exposure groups 48 hours later in a dose-dependent manner.The only exception was the 10μmol/L group.The distribution of BACE-1 in the retina did not exhibit obvious changes,and no distinctive increase in the activation of retinal microglia was apparent.Similarly,retinal synaptophysin expression did not exhibit any clear changes.These data suggest that lead exposure can result in the upregulation of retinal neuron BACE-1 expression in the early period of development and further increase the overproduction of Aβ1-40 in the retina.Our results provided novel insight into the molecular mechanisms underlying environmentally-induced Alzheimer's disease.
