Background:Adenoid hypertrophy(AH)is a common pediatric disease that signifi-cantly impacts the growth and quality of life of children.However,there is no replica-ble and valid model for AH.Methods:An AH rat model was...Background:Adenoid hypertrophy(AH)is a common pediatric disease that signifi-cantly impacts the growth and quality of life of children.However,there is no replica-ble and valid model for AH.Methods:An AH rat model was developed via comprehensive allergic sensitization,chronic inflammation induction,and chronic intermittent hypoxia(CIH).The modeling process involved three steps:female Sprague-Dawley rats(aged 4-5 weeks)were used for modeling.Allergen sensitization was induced via intraperitoneal administra-tion and intranasal provocation using ovalbumin(OVA);chronic nasal inflammation was induced through intranasal lipopolysaccharide(LPS)administration for sustained nasal irritation;CIH akin to obstructive sleep apnea/hypopnea syndrome was induced using an animal hypoxia chamber.Postmodel establishment,behaviors,and histologi-cal changes in nasopharynx-associated lymphoid tissue(NALT)and nasal mucosa were assessed.Arterial blood gas analysis and quantification of serum and tissue levels of(interleukin)IL-4 and IL-13,OVA-specific immunoglobulin E(sIgE),eosinophil cationic protein(ECP),tumor necrosis factor(TNF-α),IL-17,and transforming growth factor(TGF)-βwere conducted for assessment.The treatment group received a combination of mometasone furoate and montelukast sodium for a week and then was evaluated.Results:Rats exhibited notable nasal symptoms and hypoxia after modeling.Histopathological analysis revealed NALT follicle hypertrophy and nasal mucosa in-flammatory cell infiltration.Elevated IL-4,IL-13,IL-17,OVA-sIgE,ECP,and TNF-αlev-els and reduced TGF-βlevels were observed in the serum and tissue of model-group rats.After a week of treatment,the treatment group exhibited symptom and inflam-matory factor improvement.Conclusion:The model effectively simulates AH symptoms and pathological changes.But it should be further validated for genetic,immunological,and hormonal back-grounds in the currently used and other strains and species.展开更多
Emerging evidence showed that 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) could induce expression of certain reactivation-associated genes in astrocytes, however, the consequent cellular effects and molecular mechanisms...Emerging evidence showed that 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) could induce expression of certain reactivation-associated genes in astrocytes, however, the consequent cellular effects and molecular mechanisms are still unclear. During the process of astrocyte reactivation, migration is a critical cellular event. In the present study, we employed woundhealing assay and Transwell? motility assay to explore the effects of TCDD on cell migration in primary cultured rat cortical astrocytes. We found that upon TCDD treatments at relative low concentrations(10^(-10) and/or 10^(-9) mol/L), the ability of primary astrocytes to migrate horizontally and vertically was promoted. In line with this cellular effect, the mR NA expression of two promigratory genes, including cell division cycle 42(CDC42) and matrix metalloproteinase 2(MMP2)was induced by TCDD treatment. Dioxin exerts its toxic effects mainly through aryl hydrocarbon receptor(AhR) pathway. So the role of AhR pathway in the pro-migratory effects of TCDD was examined using an AhR antagonist, CH223191. We found that application of CH223191 significantly reversed the pro-migratory effects of TCDD. Interestingly, the basal ability of horizontal migration as well as basal levels of CDC42 and MMP2 expression were dramatically reduced suggesting a possible physiological role of AhR in maintaining the endogenous migration ability of the primary astrocytes. These findings support the notion that dioxin promotes astrocyte reactivation at molecular and cellular levels.展开更多
Dibutyltin dilaurate functions as a stabilizer for polyvinyl chloride. In this study, experimental rats were intragastrically administered 5, 10, or 20 mg/kg dibutyltin dilaurate to model sub-chronic poisoning. After ...Dibutyltin dilaurate functions as a stabilizer for polyvinyl chloride. In this study, experimental rats were intragastrically administered 5, 10, or 20 mg/kg dibutyltin dilaurate to model sub-chronic poisoning. After exposure, our results showed the activities of superoxide dismutase and glutathione peroxidase decreased in rat brain tissue, while the malondialdehyde and nitric oxide content, as well as nitric oxide synthase activity in rat brain tissue increased. The cell cycle in the right parietal cortex was disordered and the rate of apoptosis increased. DNA damage was aggravated in the cerebral cortex, and the ultrastructure of the right parietal cortex tissues was altered. The above changes became more apparent with exposure to increasing doses of dibutyltin dilaurate. Our experimental findings confirmed the neurotoxicity of dibutyltin dilaurate in rat brain tissues, and demonstrated that the poisoning was dose-dependent.展开更多
The automatic feature extracting and matching for large amount of linear pushbroom imagery with higher and higher resolution is urgent and challenging in three dimensional reconstructions, remote sensing and mapping. ...The automatic feature extracting and matching for large amount of linear pushbroom imagery with higher and higher resolution is urgent and challenging in three dimensional reconstructions, remote sensing and mapping. Affine & scale-invariant heterogeneous pyramid feature is proposed in this paper, along with the new scale-invariant analysis method, the detecting of the key points, the affine & scale-invariant descriptor, the steering method of the matching, and the quasi-dense matching algorithm based on the extensive epipolar geometry. The automatic matching is devised for the linear pushbroom imagery. The whole process is executed on lunar images of the highest resolution of ~7 m/pixel(or ~1 m/pixel in the lower orbits) from the Chinese Chang'e 2 satellite, it runs robustly at present, and resulting in large amounts of well-distributed-correspondences with accuracy of 0.3 pixels and excellent reliability, which gives great support for the further exploration both on the Moon and the Earth.展开更多
BACKGROUND:The establishment of a rat model of complete transected spinal cord injury lacks technological specifications.The current models lack concordance and reliability,and the death rate of the experimental anima...BACKGROUND:The establishment of a rat model of complete transected spinal cord injury lacks technological specifications.The current models lack concordance and reliability,and the death rate of the experimental animals is high.Therefore,there is a great need for a reliable model to apply clinical applications of therapy.OBJECTIVE:To construct a rat model of complete transected spinal cord injury characterized by stability,reproducibility,and a high animal survival rate.DESIGN:Completely randomized controlled study.SETTING:Department of Neurosurgery,Xiangya Hospital of Central South University.MATERIALS:Fifty-five healthy specific pathogen free grade adult female Sprague Dawley rats were provided by the Experimental Animal Department,Xiangya Medical College,Central South University.Olympus BX51 imaging collecting analytic system was provided by Olympus Company,Japan;and SEN-7203 Nihon-Kohden electrical stimulator by Nihon Kohden,Japan.METHODS:This study was performed at the Laboratory of Neurosurgery,Xiangya Hospital of Central South University from April to June 2006.Experimental grouping:55 rats were randomly divided into model group(n=40)and sham surgery group(n=15).In the model group,a self-made sliver hook was passed through the ventral side to support the spinal cord at the T12 segment and to shear it off.A complete transected spinal cord,2 mm in length,was resected.In the sham surgery group,the spinal cord was identically exposed.The dura mater of the spinal cord was cut open,but the spinal cord was not damaged.MAIN OUTCOME MEASURES:Histopathological changes after spinal cord injury at L2 segment were observed subsequent to hematoxylin and eosin staining under optical microscopy.Olympus BX51 imaging collecting analytic system was used to count spinal cord ventral horn neurons.Motor function of rat hindlimb was evaluated with the Basso,Beattie and Bresnahan(BBB)scale.Paraplegia was evaluated as 0 point,and complete normality as 21 points.Somatosensory-evoked potential was measured using Nihon-Kohden electric stimulator at 21 days post-operation.RESULTS:A total of 82%(33/40)rats survived longer than 30 days after modeling.Pathological changes of spinal cord tissue:degenerative and necrotic pathological changes appeared in the model group after surgery;for example,neuronal swelling,chromatinolysis,and karyopyknosis.The spinal cord in the sham surgery group displayed mild edema 24 hours after surgery,gradually recovering to normal levels.Quantification of spinal cord ventral horn neurons:the number of spinal cord ventral horn neurons in the model group was less than in the sham surgery group at 24 hours,as well as 7 and 21 days after surgery(P〈0.01);while,the number at 7 and 21 days after surgery decreased compared to 24 hours after surgery(P〈0.01).Motor function changes:Rats in the sham operation group moved lightly abnormally following anesthesia recovery and then moved normally 7 days after surgery.BBB scores in the model group were less than in the sham surgery group 21 days after surgery(P〈0.01).BBB scores of both lower extremities increased slightly 7 days after surgery(P〈0.01);however,voluntary motor function of both lower extremities was still not recovered 30 days after surgery.Changes of somatosensory-evoked potential:wave form of somatosensory-evoked potential was normal in the sham surgery group 21 days after surgery,but recovered wave form was not recorded in the model group.CONCLUSION:Results from spinal cord histopathology,cytology,motor function,and somatosensory-evoked potential suggested that the complete transected spinal cord injury model in this study was stable,reliable,and reproducible.Furthermore,the survival rate of experimental animals was high.展开更多
According to the soft-switching pulsed SAW (Submerged arc weld) weld power supply based on the double closed-loop constant current control mode, a small signal mathematic model of main circuit of soft-switching SAW in...According to the soft-switching pulsed SAW (Submerged arc weld) weld power supply based on the double closed-loop constant current control mode, a small signal mathematic model of main circuit of soft-switching SAW inverter was established by applying the method of three-terminal switching device modeling method, and the math-ematic model of double closed-loop phase-shift control system circuit was established by applying the method of state-space averaging method. Dynamic performance of the inverter was analyzed on base of the established math-ematic model, and the tested wave of dynamic performance was shown by experimentation. Research and experimentation show that relation between structure of the power source circuit and dynamic performance of the controlling system can be announced by the established mathematic model, which provides development of power supply and optimized design of controlling parameter with theoretical guidance.展开更多
Glioblastoma(GBM)is an aggressive brain tumor with limited treatment options and a dismal prognosis.While immunotherapy has shown promise in treating some solid tumors,the treatment of GBM has been mostly unsuccessful...Glioblastoma(GBM)is an aggressive brain tumor with limited treatment options and a dismal prognosis.While immunotherapy has shown promise in treating some solid tumors,the treatment of GBM has been mostly unsuccessful because of a lack of targetable tumor antigens and high tumor heterogeneity.Here,we report RCAN1-4 as a novel tumor antigen derived from alternative splicing induced by the transcription factor C/EBPβ.Both C/EBPβand RCAN1-4 are highly expressed in GBM and glioma stem cells as mesenchymal subtype hallmarks.We report an immunogenic HLA-A24-specific splicing junction epitope within exon 4 and exon 5 that is unique to RCAN1-4.This epitope was validated for its ability to stimulate T cell responses in HLA-A24^(+)donors and GBM patients,leading us to identify RCAN1-4-reactive T cell receptors(TCRs)for the construction of TCR-engineered T cells(TCR-T cells).Functional studies of TCR-Ts demonstrated the in vitro and in vivo killing of RCAN1-4pos GBM tumor cells,highlighting its potential as an immunotherapeutic target in mesenchymal GBM.展开更多
To explore how decomposed Microcystis-dominant cyanobacterial blooms affect submerged macrophytes,the submerged plant Myriophyllum spicatum was exposed to cell extracts from microcystin(MC)-and non-MC-producing Microc...To explore how decomposed Microcystis-dominant cyanobacterial blooms affect submerged macrophytes,the submerged plant Myriophyllum spicatum was exposed to cell extracts from microcystin(MC)-and non-MC-producing Microcystis strains in a laboratory experiment.Results showed that both Mcracystis cell extracts exerted obvious damages to plant biomass,photosynthesis,primary and secondary metabolism measures,and resistance of plant antioxidant systems,with MC-producing Microcystis having stronger effects due to the presence of MCs.Cyanotoxins other than MCs responsible for the negative effects from both strains needs further identification.The Shannon diversity and Chao1 indices of epiphytic and planktonic bacteria were decreased by the cell extracts from both Microcystis strains.However,epiphytic and planktonic bacterial communities responded differently to cell extracts at the genus level.The dominant genera of planktonic bacteria including Enterobacter,Pseudomonas,and Novosphingobium from phylum Proteobacteria,Chryseobacterium from phylum Bacteroidetes,and Microbacterium from Actinobacteriota in the treatments with cell extracts were previously reported to have strains with algicidal and MC-degrading capabilities.B acterial genes associated with energy production and conversion,amino acid transport and metabolism,and inorganic ion transport and metabolism,were more abundant in both treatments than the control for planktonic bacteria,but less abundant for epiphytic bacteria.We speculate that planktonic bacterial communities have the potential to use and degrade substances derived from Microcystis cell extracts,which may be beneficial for M.spicatum to alleviate damages from Microcystis.Further research is needed to verify the structure and function dynamics of epiphytic and planktonic bacteria in the interaction between cyanobacteria and submerged macrophytes.展开更多
Nuclear power plays a key role as renewable energy in alleviating the worldwide energy shortage.The material degradation caused by high-temperature and high-flux neutron irradiation is the most concerning issue for nu...Nuclear power plays a key role as renewable energy in alleviating the worldwide energy shortage.The material degradation caused by high-temperature and high-flux neutron irradiation is the most concerning issue for nuclear reactor safety.A large number of He atoms produced through the(n,α)transmutation reaction diffuse and migrate in metals and accumulate to form He bubbles because of the extremely low solubility of He atoms in metal materials.The helium bubbles gather at the grain boundary or grain to cause swelling,hardening,embrittlement,and other damages to the in-core structural components.This paper mainly summarizes the research progress on He irradiation in steel and iron-based alloys,including the diffusion and accumulation of He atoms,the nucleation and growth of He bubbles,and the microstructure and macroscopic degradation of material performance caused by He irradiation.The mechanism of helium irradiation-induced corrosion in steel and iron-based alloys in recent years is reviewed as well.Moreover,the investigations on irradiation performance in additive manufactured stainless steels are summarized,and the mechanism of irradiation resistance is prospected.展开更多
BACKGROUND: To this date, specific molecular markers for early diagnosis and prognosis monitoring of craniocerebral injury in clinical medicine do not exist. Therefore, differential detection of specific proteins mig...BACKGROUND: To this date, specific molecular markers for early diagnosis and prognosis monitoring of craniocerebral injury in clinical medicine do not exist. Therefore, differential detection of specific proteins might play an important role in diagnosis and treatment of this type of brain injury. OBJECTIVE: To compare differential cerebral cortical protein expression of craniocerebral injury patients and normal subjects through the use of proteomics. DESIGN: Contrast observation. SETTING: Department of Neurosurgery, Xiangya Hospital of Central South University. PARTICIPANTS: Ten patients (6 males and 4 females, 20 58 years old), with severe craniocerebral injury, were selected at the Department of Neurosurgery, Xiangya Hospital of Central South University, from June 2004 to December 2006. All patients were diagnosed with CT test and Glasgow test (scores 〈 8). Surgery was performed 4-12 hours after craniocerebral injury, and injured cortical tissues of the frontal and temporal lobes were resected for sampling. At the same time, control cortical tissues were collected from frontal and temporal lobes of 2 epileptic patients who underwent hippocampus-nucleus amygdala resection, and 2 lateral ventricular tumor patients who underwent tumor resection. The participants and their relatives provided confirmed consent, and this study received confirrned consent from the local ethics committee. METHODS: Ten samples from injured patients and 4 normal samples were compared through the use of proteomics. Total protein was separated by using two-dimensional electrophoresis with immobilized pH gradients, and the differential protein expressions were compared using image analysis after blue-sliver staining. Differential protein spot expressions were analyzed with a matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI/TOF MS) and electrospray ionization-quadrupole time of flight mass spectrometry (ESI-Qq TOF MS). MAIN OUTCOME MEASURES:① Two-dimensional electrophoresis of protein from cerebral cortex; ② differential protein expression. RESULTS: ① Two-dimensional electrophoresis of protein from cerebral cortex: two-dimensional gel electrophoretogram, which is considered to have high resolution and consistent duplication, was performed on injured cortical tissues and normal cortical tissues. The image analysis system detected 21 differential protein spots. ② Differential protein spot expressions: mass spectrometry resulted in 17 differential protein spots that related to metabolic response, oxidative stress response, and signal transduction. CONCLUSION: MALDI/TOF MS and ESI-Qq TOF MS are exceptional methods for evaluating differential protein expression. Results from this study indicated 17 different craniocerebral injury-associated proteins.展开更多
To understand the distribution of phytoplankton functional groups(PFGs)and key factors on their compositions in different watersheds of the Huanghe(Yellow)River basin,25 river sites and 25 lake-reservoirs sites were s...To understand the distribution of phytoplankton functional groups(PFGs)and key factors on their compositions in different watersheds of the Huanghe(Yellow)River basin,25 river sites and 25 lake-reservoirs sites were selected.The contents of nephelometric turbidity(NTU),total nitrogen(TN),and total phosphorus(TP)were significantly higher in rivers than that in lakes or reservoirs,whereas the pH and CODMn(chemical oxygen demand or potassium permanganate index)were lower.Results show that,27 PFGs,namely,assemblages A,B,C,D,E,F,G,H,J,K,LM,Lo,M,MP,N,P,S1,S2,T,TC,W1,W2,X1,X2,X3,XPh,and Y,were identified.Additionally,ANOSIM correlation analysis demonstrated significant differences in PFG composition between the riverine and lake-reservoir sections in the Huanghe River basin.In the riverine watersheds,the group MP was dominant,while assemblages B and J were prevalent in lakes and reservoirs.The Mantel correlation tests and RDA analysis showed that environmental variables,such as NTU,water temperature(WT),conductivity(Cond),and TP,were key driving factors of shaping the dominant PFGs of the study area.Using the Venn diagram based on variation partitioning analysis,PFGs were mainly influenced by WT and TP in lake-reservoir sites,while in the river sites were affected mainly by geo-climatic variables.This study helps understanding the PFGs in river ecosystems,and unraveling the key driving factors in different watersheds,which shall be important for the protection and management of entire Huanghe River basin.展开更多
Pipe belt conveyor is a new type of environmentally friendly and efficient bulk conveying equipment.In the design of the roller,the belt and the driving motor of pipe belt conveyor,the sag resistance is a key paramete...Pipe belt conveyor is a new type of environmentally friendly and efficient bulk conveying equipment.In the design of the roller,the belt and the driving motor of pipe belt conveyor,the sag resistance is a key parameter.Meanwhile,the normal force between the conveyor belt and the roller group is the other important factor need be considered and has a great influence on the sag resistance.This paper analyzes a pipe belt conveyor with a diameter of 150 mm to study the calculation method of normal force.And the relationship between the normal force and the sag resistance is explored.Firstly,the normal force is decomposed into three components related to the forming force of belt,material gravity and belt gravity.So it can be expressed as a linear combination of these three quantities,and the coefficients of each component are obtained based on the dynamic analysis of belt-roller.The results show that the coefficient is mainly affected by the material filling rate,and is almost not affected by the distance between the rollers and the density of the material.The calculation method of the normal force is eventually obtained.Secondly,the normal force in the case of different material filling rates is tested by experiments,and the calculation method of the normal force is verified.Thirdly,the variation law of the sag resistance in the case of different roller group spacing and material filling rate is studied by the dynamic model.It is found that the roller group spacing and material filling rate affects the sag resistance by changing the normal force.There is a power function relationship between the sag resistance and the normal force.In the case of different roller group spacing and material filling rate,the relationship among the sag resistance and the normal force remains unchanged.This study results are of great significance to the design of pipe belt conveyor.展开更多
The paper summarizes, contrasts and expands the definitions of Internet economics, puts forward the theory of Internet economics development stage and analyzes the reason of the development of Internet economics.
基金This work was financially supported by the National Natural Science Foundation of China(grant number:8217150152)the Clinical Science and Technology Innovation Project of Shanghai Shenkang Hospital Development Center(grant number:SHDC12021102)the Shanghai Three-Year Action Plan to Further Accelerate the Development of Traditional Chinese Medicine Inheritance and Innovation(grant number:ZY(2021-2023)-0209-05).
文摘Background:Adenoid hypertrophy(AH)is a common pediatric disease that signifi-cantly impacts the growth and quality of life of children.However,there is no replica-ble and valid model for AH.Methods:An AH rat model was developed via comprehensive allergic sensitization,chronic inflammation induction,and chronic intermittent hypoxia(CIH).The modeling process involved three steps:female Sprague-Dawley rats(aged 4-5 weeks)were used for modeling.Allergen sensitization was induced via intraperitoneal administra-tion and intranasal provocation using ovalbumin(OVA);chronic nasal inflammation was induced through intranasal lipopolysaccharide(LPS)administration for sustained nasal irritation;CIH akin to obstructive sleep apnea/hypopnea syndrome was induced using an animal hypoxia chamber.Postmodel establishment,behaviors,and histologi-cal changes in nasopharynx-associated lymphoid tissue(NALT)and nasal mucosa were assessed.Arterial blood gas analysis and quantification of serum and tissue levels of(interleukin)IL-4 and IL-13,OVA-specific immunoglobulin E(sIgE),eosinophil cationic protein(ECP),tumor necrosis factor(TNF-α),IL-17,and transforming growth factor(TGF)-βwere conducted for assessment.The treatment group received a combination of mometasone furoate and montelukast sodium for a week and then was evaluated.Results:Rats exhibited notable nasal symptoms and hypoxia after modeling.Histopathological analysis revealed NALT follicle hypertrophy and nasal mucosa in-flammatory cell infiltration.Elevated IL-4,IL-13,IL-17,OVA-sIgE,ECP,and TNF-αlev-els and reduced TGF-βlevels were observed in the serum and tissue of model-group rats.After a week of treatment,the treatment group exhibited symptom and inflam-matory factor improvement.Conclusion:The model effectively simulates AH symptoms and pathological changes.But it should be further validated for genetic,immunological,and hormonal back-grounds in the currently used and other strains and species.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Nos.XDB14030401,XDB14030402)the Natural Science Foundation of China (Nos.21377160,21525730)Tianjin Municipal Science and Technology Commission (No.14JCQNJC11300)
文摘Emerging evidence showed that 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) could induce expression of certain reactivation-associated genes in astrocytes, however, the consequent cellular effects and molecular mechanisms are still unclear. During the process of astrocyte reactivation, migration is a critical cellular event. In the present study, we employed woundhealing assay and Transwell? motility assay to explore the effects of TCDD on cell migration in primary cultured rat cortical astrocytes. We found that upon TCDD treatments at relative low concentrations(10^(-10) and/or 10^(-9) mol/L), the ability of primary astrocytes to migrate horizontally and vertically was promoted. In line with this cellular effect, the mR NA expression of two promigratory genes, including cell division cycle 42(CDC42) and matrix metalloproteinase 2(MMP2)was induced by TCDD treatment. Dioxin exerts its toxic effects mainly through aryl hydrocarbon receptor(AhR) pathway. So the role of AhR pathway in the pro-migratory effects of TCDD was examined using an AhR antagonist, CH223191. We found that application of CH223191 significantly reversed the pro-migratory effects of TCDD. Interestingly, the basal ability of horizontal migration as well as basal levels of CDC42 and MMP2 expression were dramatically reduced suggesting a possible physiological role of AhR in maintaining the endogenous migration ability of the primary astrocytes. These findings support the notion that dioxin promotes astrocyte reactivation at molecular and cellular levels.
文摘Dibutyltin dilaurate functions as a stabilizer for polyvinyl chloride. In this study, experimental rats were intragastrically administered 5, 10, or 20 mg/kg dibutyltin dilaurate to model sub-chronic poisoning. After exposure, our results showed the activities of superoxide dismutase and glutathione peroxidase decreased in rat brain tissue, while the malondialdehyde and nitric oxide content, as well as nitric oxide synthase activity in rat brain tissue increased. The cell cycle in the right parietal cortex was disordered and the rate of apoptosis increased. DNA damage was aggravated in the cerebral cortex, and the ultrastructure of the right parietal cortex tissues was altered. The above changes became more apparent with exposure to increasing doses of dibutyltin dilaurate. Our experimental findings confirmed the neurotoxicity of dibutyltin dilaurate in rat brain tissues, and demonstrated that the poisoning was dose-dependent.
基金supported by the National Defense Science and Technology Product of China (No. 20060826)
文摘The automatic feature extracting and matching for large amount of linear pushbroom imagery with higher and higher resolution is urgent and challenging in three dimensional reconstructions, remote sensing and mapping. Affine & scale-invariant heterogeneous pyramid feature is proposed in this paper, along with the new scale-invariant analysis method, the detecting of the key points, the affine & scale-invariant descriptor, the steering method of the matching, and the quasi-dense matching algorithm based on the extensive epipolar geometry. The automatic matching is devised for the linear pushbroom imagery. The whole process is executed on lunar images of the highest resolution of ~7 m/pixel(or ~1 m/pixel in the lower orbits) from the Chinese Chang'e 2 satellite, it runs robustly at present, and resulting in large amounts of well-distributed-correspondences with accuracy of 0.3 pixels and excellent reliability, which gives great support for the further exploration both on the Moon and the Earth.
基金the Scientific and Technological Foundation of Hunan Public Health Bureau,No.B2006-034
文摘BACKGROUND:The establishment of a rat model of complete transected spinal cord injury lacks technological specifications.The current models lack concordance and reliability,and the death rate of the experimental animals is high.Therefore,there is a great need for a reliable model to apply clinical applications of therapy.OBJECTIVE:To construct a rat model of complete transected spinal cord injury characterized by stability,reproducibility,and a high animal survival rate.DESIGN:Completely randomized controlled study.SETTING:Department of Neurosurgery,Xiangya Hospital of Central South University.MATERIALS:Fifty-five healthy specific pathogen free grade adult female Sprague Dawley rats were provided by the Experimental Animal Department,Xiangya Medical College,Central South University.Olympus BX51 imaging collecting analytic system was provided by Olympus Company,Japan;and SEN-7203 Nihon-Kohden electrical stimulator by Nihon Kohden,Japan.METHODS:This study was performed at the Laboratory of Neurosurgery,Xiangya Hospital of Central South University from April to June 2006.Experimental grouping:55 rats were randomly divided into model group(n=40)and sham surgery group(n=15).In the model group,a self-made sliver hook was passed through the ventral side to support the spinal cord at the T12 segment and to shear it off.A complete transected spinal cord,2 mm in length,was resected.In the sham surgery group,the spinal cord was identically exposed.The dura mater of the spinal cord was cut open,but the spinal cord was not damaged.MAIN OUTCOME MEASURES:Histopathological changes after spinal cord injury at L2 segment were observed subsequent to hematoxylin and eosin staining under optical microscopy.Olympus BX51 imaging collecting analytic system was used to count spinal cord ventral horn neurons.Motor function of rat hindlimb was evaluated with the Basso,Beattie and Bresnahan(BBB)scale.Paraplegia was evaluated as 0 point,and complete normality as 21 points.Somatosensory-evoked potential was measured using Nihon-Kohden electric stimulator at 21 days post-operation.RESULTS:A total of 82%(33/40)rats survived longer than 30 days after modeling.Pathological changes of spinal cord tissue:degenerative and necrotic pathological changes appeared in the model group after surgery;for example,neuronal swelling,chromatinolysis,and karyopyknosis.The spinal cord in the sham surgery group displayed mild edema 24 hours after surgery,gradually recovering to normal levels.Quantification of spinal cord ventral horn neurons:the number of spinal cord ventral horn neurons in the model group was less than in the sham surgery group at 24 hours,as well as 7 and 21 days after surgery(P〈0.01);while,the number at 7 and 21 days after surgery decreased compared to 24 hours after surgery(P〈0.01).Motor function changes:Rats in the sham operation group moved lightly abnormally following anesthesia recovery and then moved normally 7 days after surgery.BBB scores in the model group were less than in the sham surgery group 21 days after surgery(P〈0.01).BBB scores of both lower extremities increased slightly 7 days after surgery(P〈0.01);however,voluntary motor function of both lower extremities was still not recovered 30 days after surgery.Changes of somatosensory-evoked potential:wave form of somatosensory-evoked potential was normal in the sham surgery group 21 days after surgery,but recovered wave form was not recorded in the model group.CONCLUSION:Results from spinal cord histopathology,cytology,motor function,and somatosensory-evoked potential suggested that the complete transected spinal cord injury model in this study was stable,reliable,and reproducible.Furthermore,the survival rate of experimental animals was high.
文摘According to the soft-switching pulsed SAW (Submerged arc weld) weld power supply based on the double closed-loop constant current control mode, a small signal mathematic model of main circuit of soft-switching SAW inverter was established by applying the method of three-terminal switching device modeling method, and the math-ematic model of double closed-loop phase-shift control system circuit was established by applying the method of state-space averaging method. Dynamic performance of the inverter was analyzed on base of the established math-ematic model, and the tested wave of dynamic performance was shown by experimentation. Research and experimentation show that relation between structure of the power source circuit and dynamic performance of the controlling system can be announced by the established mathematic model, which provides development of power supply and optimized design of controlling parameter with theoretical guidance.
基金supported by the Botha-Chan Research Fund,the Office of the Assistant Secretary of Defense for Health Affairs through award no.HT9425-24-1-0623(I.R.)the Brain Tumor Funders'Collaborative,the Ellie Kavalieros DIPG Research Fund+6 种基金the UPMC Children’s Hospital of Pittsburgh Foundation(G.K.,I.R.)the Children’s Brain Tumor Network(I.F.P.),a stipend from the Central South University Xiangya School of Medicine and University of Pittsburgh(Z.X.)by grant NS117742 from the National Institute of Health(T.G.F.)support from the Jesse H.&Mary Jones Gibbs Endowed Chair(T.G.F)supported in part by the University of Pittsburgh Center for Research Computing,RRID:SCR_022735through NIH award number S10OD028483Work performed in the UPMC Hillman Cancer Center Tissue and Research Pathology Services Shared Resource Facility and the services and instruments used in this project were supported,in part,by the University of Pittsburgh and the NCI of the NIH under Award Number P30CA047904.
文摘Glioblastoma(GBM)is an aggressive brain tumor with limited treatment options and a dismal prognosis.While immunotherapy has shown promise in treating some solid tumors,the treatment of GBM has been mostly unsuccessful because of a lack of targetable tumor antigens and high tumor heterogeneity.Here,we report RCAN1-4 as a novel tumor antigen derived from alternative splicing induced by the transcription factor C/EBPβ.Both C/EBPβand RCAN1-4 are highly expressed in GBM and glioma stem cells as mesenchymal subtype hallmarks.We report an immunogenic HLA-A24-specific splicing junction epitope within exon 4 and exon 5 that is unique to RCAN1-4.This epitope was validated for its ability to stimulate T cell responses in HLA-A24^(+)donors and GBM patients,leading us to identify RCAN1-4-reactive T cell receptors(TCRs)for the construction of TCR-engineered T cells(TCR-T cells).Functional studies of TCR-Ts demonstrated the in vitro and in vivo killing of RCAN1-4pos GBM tumor cells,highlighting its potential as an immunotherapeutic target in mesenchymal GBM.
基金Supported by the National Program for the Introduction of High-end Foreign Experts(No.G2021026024L)the National Natural Science Foundation of China(Nos.31700405,U1904124)+1 种基金the Major Public Welfare Projects in Henan Province(No.201300311300)the Breeding Project of Henan Normal University(No.HNU2021PL05)。
文摘To explore how decomposed Microcystis-dominant cyanobacterial blooms affect submerged macrophytes,the submerged plant Myriophyllum spicatum was exposed to cell extracts from microcystin(MC)-and non-MC-producing Microcystis strains in a laboratory experiment.Results showed that both Mcracystis cell extracts exerted obvious damages to plant biomass,photosynthesis,primary and secondary metabolism measures,and resistance of plant antioxidant systems,with MC-producing Microcystis having stronger effects due to the presence of MCs.Cyanotoxins other than MCs responsible for the negative effects from both strains needs further identification.The Shannon diversity and Chao1 indices of epiphytic and planktonic bacteria were decreased by the cell extracts from both Microcystis strains.However,epiphytic and planktonic bacterial communities responded differently to cell extracts at the genus level.The dominant genera of planktonic bacteria including Enterobacter,Pseudomonas,and Novosphingobium from phylum Proteobacteria,Chryseobacterium from phylum Bacteroidetes,and Microbacterium from Actinobacteriota in the treatments with cell extracts were previously reported to have strains with algicidal and MC-degrading capabilities.B acterial genes associated with energy production and conversion,amino acid transport and metabolism,and inorganic ion transport and metabolism,were more abundant in both treatments than the control for planktonic bacteria,but less abundant for epiphytic bacteria.We speculate that planktonic bacterial communities have the potential to use and degrade substances derived from Microcystis cell extracts,which may be beneficial for M.spicatum to alleviate damages from Microcystis.Further research is needed to verify the structure and function dynamics of epiphytic and planktonic bacteria in the interaction between cyanobacteria and submerged macrophytes.
基金sponsored by the National Natural Science Foundation of China(Grant No.52073176)the Shenzhen International Cooperation Research Science and Technology Program(No.GJHZ20200731095203011).
文摘Nuclear power plays a key role as renewable energy in alleviating the worldwide energy shortage.The material degradation caused by high-temperature and high-flux neutron irradiation is the most concerning issue for nuclear reactor safety.A large number of He atoms produced through the(n,α)transmutation reaction diffuse and migrate in metals and accumulate to form He bubbles because of the extremely low solubility of He atoms in metal materials.The helium bubbles gather at the grain boundary or grain to cause swelling,hardening,embrittlement,and other damages to the in-core structural components.This paper mainly summarizes the research progress on He irradiation in steel and iron-based alloys,including the diffusion and accumulation of He atoms,the nucleation and growth of He bubbles,and the microstructure and macroscopic degradation of material performance caused by He irradiation.The mechanism of helium irradiation-induced corrosion in steel and iron-based alloys in recent years is reviewed as well.Moreover,the investigations on irradiation performance in additive manufactured stainless steels are summarized,and the mechanism of irradiation resistance is prospected.
基金the National Natural Science Foundation of China, No. 30500558,30672149Program for New Century Excellent Talents in University,No.NCET2007-70
文摘BACKGROUND: To this date, specific molecular markers for early diagnosis and prognosis monitoring of craniocerebral injury in clinical medicine do not exist. Therefore, differential detection of specific proteins might play an important role in diagnosis and treatment of this type of brain injury. OBJECTIVE: To compare differential cerebral cortical protein expression of craniocerebral injury patients and normal subjects through the use of proteomics. DESIGN: Contrast observation. SETTING: Department of Neurosurgery, Xiangya Hospital of Central South University. PARTICIPANTS: Ten patients (6 males and 4 females, 20 58 years old), with severe craniocerebral injury, were selected at the Department of Neurosurgery, Xiangya Hospital of Central South University, from June 2004 to December 2006. All patients were diagnosed with CT test and Glasgow test (scores 〈 8). Surgery was performed 4-12 hours after craniocerebral injury, and injured cortical tissues of the frontal and temporal lobes were resected for sampling. At the same time, control cortical tissues were collected from frontal and temporal lobes of 2 epileptic patients who underwent hippocampus-nucleus amygdala resection, and 2 lateral ventricular tumor patients who underwent tumor resection. The participants and their relatives provided confirmed consent, and this study received confirrned consent from the local ethics committee. METHODS: Ten samples from injured patients and 4 normal samples were compared through the use of proteomics. Total protein was separated by using two-dimensional electrophoresis with immobilized pH gradients, and the differential protein expressions were compared using image analysis after blue-sliver staining. Differential protein spot expressions were analyzed with a matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI/TOF MS) and electrospray ionization-quadrupole time of flight mass spectrometry (ESI-Qq TOF MS). MAIN OUTCOME MEASURES:① Two-dimensional electrophoresis of protein from cerebral cortex; ② differential protein expression. RESULTS: ① Two-dimensional electrophoresis of protein from cerebral cortex: two-dimensional gel electrophoretogram, which is considered to have high resolution and consistent duplication, was performed on injured cortical tissues and normal cortical tissues. The image analysis system detected 21 differential protein spots. ② Differential protein spot expressions: mass spectrometry resulted in 17 differential protein spots that related to metabolic response, oxidative stress response, and signal transduction. CONCLUSION: MALDI/TOF MS and ESI-Qq TOF MS are exceptional methods for evaluating differential protein expression. Results from this study indicated 17 different craniocerebral injury-associated proteins.
基金Supported by the Young Backbone Teachers Project of Henan Province (No. 2020GGJS064)the Key Scientific and Technological Project of Henan Province (No. 232102321056)+1 种基金the Scientific Fund of Henan Normal University (No. 2020QK02)the Project of Huanghe River Fisheries Resources and Environment Investigation from the MARA,China,and the Observation and Research Station on Water Ecosystem in Danjiangkou Reservoir of Henan Province
文摘To understand the distribution of phytoplankton functional groups(PFGs)and key factors on their compositions in different watersheds of the Huanghe(Yellow)River basin,25 river sites and 25 lake-reservoirs sites were selected.The contents of nephelometric turbidity(NTU),total nitrogen(TN),and total phosphorus(TP)were significantly higher in rivers than that in lakes or reservoirs,whereas the pH and CODMn(chemical oxygen demand or potassium permanganate index)were lower.Results show that,27 PFGs,namely,assemblages A,B,C,D,E,F,G,H,J,K,LM,Lo,M,MP,N,P,S1,S2,T,TC,W1,W2,X1,X2,X3,XPh,and Y,were identified.Additionally,ANOSIM correlation analysis demonstrated significant differences in PFG composition between the riverine and lake-reservoir sections in the Huanghe River basin.In the riverine watersheds,the group MP was dominant,while assemblages B and J were prevalent in lakes and reservoirs.The Mantel correlation tests and RDA analysis showed that environmental variables,such as NTU,water temperature(WT),conductivity(Cond),and TP,were key driving factors of shaping the dominant PFGs of the study area.Using the Venn diagram based on variation partitioning analysis,PFGs were mainly influenced by WT and TP in lake-reservoir sites,while in the river sites were affected mainly by geo-climatic variables.This study helps understanding the PFGs in river ecosystems,and unraveling the key driving factors in different watersheds,which shall be important for the protection and management of entire Huanghe River basin.
基金Supported by National Natural Science Foundation of China (Grant No. 51705144)Hunan Provincial Science and Technology Major Project of China (Grant No. 2015GK1003)Jiangsu Provincial Mine Electromechanical Equipment Key Laboratory Development Fund of China (Grant No. JSKL-MMEE-2018-2)
文摘Pipe belt conveyor is a new type of environmentally friendly and efficient bulk conveying equipment.In the design of the roller,the belt and the driving motor of pipe belt conveyor,the sag resistance is a key parameter.Meanwhile,the normal force between the conveyor belt and the roller group is the other important factor need be considered and has a great influence on the sag resistance.This paper analyzes a pipe belt conveyor with a diameter of 150 mm to study the calculation method of normal force.And the relationship between the normal force and the sag resistance is explored.Firstly,the normal force is decomposed into three components related to the forming force of belt,material gravity and belt gravity.So it can be expressed as a linear combination of these three quantities,and the coefficients of each component are obtained based on the dynamic analysis of belt-roller.The results show that the coefficient is mainly affected by the material filling rate,and is almost not affected by the distance between the rollers and the density of the material.The calculation method of the normal force is eventually obtained.Secondly,the normal force in the case of different material filling rates is tested by experiments,and the calculation method of the normal force is verified.Thirdly,the variation law of the sag resistance in the case of different roller group spacing and material filling rate is studied by the dynamic model.It is found that the roller group spacing and material filling rate affects the sag resistance by changing the normal force.There is a power function relationship between the sag resistance and the normal force.In the case of different roller group spacing and material filling rate,the relationship among the sag resistance and the normal force remains unchanged.This study results are of great significance to the design of pipe belt conveyor.
文摘The paper summarizes, contrasts and expands the definitions of Internet economics, puts forward the theory of Internet economics development stage and analyzes the reason of the development of Internet economics.