Objective Cerebral palsy(CP)is a prevalent neurodevelopmental disorder acquired during the perinatal period,with periventricular white matter injury(PWMI)serving as its primary pathological hallmark.PWMI is characteri...Objective Cerebral palsy(CP)is a prevalent neurodevelopmental disorder acquired during the perinatal period,with periventricular white matter injury(PWMI)serving as its primary pathological hallmark.PWMI is characterized by the loss of oligodendrocytes(OLs)and the disintegration of myelin sheaths,leading to impaired neural connectivity and motor dysfunction.Neural stem cells(NSCs)represent a promising regenerative source for replenishing lost OLs;however,conventional twodimensional(2D)in vitro culture systems lack the three-dimensional(3D)physiological microenvironment.Microfluidic chip technology has emerged as a powerful tool to overcome this limitation by enabling precise spatial and temporal control over 3D microenvironmental conditions,including the establishment of stable concentration gradients of bioactive molecules.Catalpol,an iridoid glycoside derived from traditional medicinal plants,exhibits dual antioxidant and anti-apoptotic properties.Despite its therapeutic potential,the capacity of catalpol to drive NSC differentiation toward OLs under biomimetic 3D conditions,as well as the underlying molecular mechanisms,remains poorly understood.This study aims to develop a microfluidic-based 3D biomimetic platform to systematically investigate the concentration-dependent effects of catalpol on promoting NSCs-to-OLs differentiation and to elucidate the role of the caveolin-1(Cav-1)signaling pathway in this process.Methods We developed a novel multiplexed microfluidic device featuring parallel microchannels with integrated gradient generators capable of establishing and maintaining precise linear concentration gradients(0-3 g/L catalpol)across 3D NSCs cultures.This platform facilitated the continuous perfusion culture of NSC-derived 3D spheroids,mimicking the dynamic in vivo microenvironment.Real-time cell viability was assessed using Calcein-AM/propidium iodide(PI)dual staining,with fluorescence imaging quantifying live/dead cell ratios.Oligodendrocyte differentiation was evaluated through quantitative reverse transcription polymerase chain reaction(qRT-PCR)for MBP and SOX10 gene expression,complemented by immunofluorescence staining to visualize corresponding protein changes.To dissect the molecular mechanism,the Cav-1-specific pharmacological inhibitor methyl‑β‑cyclodextrin(MCD)was employed to perturb the pathway,and its effects on differentiation markers were analyzed.Results Catalpol demonstrated excellent biocompatibility,with cell viability exceeding 96%across the entire tested concentration range(0-3 g/L),confirming its non-cytotoxic nature.At the optimal concentration of 0-3 g/L,catalpol significantly upregulated both MBP and SOX10 expression(P<0.05,P<0.01),indicating robust promotion of oligodendroglial differentiation.Intriguingly,Cav-1 mRNA expression was progressively downregulated during NSC differentiation into OLs.Further inhibition of Cav-1 with MCD further enhanced this effect,leading to a statistically significant increase in OL-specific gene expression(P<0.05,P<0.01),suggesting Cav-1 acts as a negative regulator of OLs differentiation.Conclusion This study established an integrated microfluidic gradient chip-3D NSC spheroid culture system,which combines the advantages of precise chemical gradient control with physiologically relevant 3D cell culture.The findings demonstrate that 3 g/L catalpol effectively suppresses Cav-1 signaling to drive NSC differentiation into functional OLs.This work not only provides novel insights into the Cav-1-dependent mechanisms of myelination but also delivers a scalable technological platform for future research on remyelination therapies,with potential applications in cerebral palsy and other white matter disorders.The platform’s modular design permits adaptation for screening other neurogenic compounds or investigating additional signaling pathways involved in OLs maturation.展开更多
The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic fu...The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic functions in the unit ball by radial derivative.Then we extend the Sharma's results.展开更多
To study the mechanism of rockburst and its spatio-temporal evolution criterion,a rockburst simulation experiment was performed on granite specimens,each with a prefabricated circular hole,under different lateral load...To study the mechanism of rockburst and its spatio-temporal evolution criterion,a rockburst simulation experiment was performed on granite specimens,each with a prefabricated circular hole,under different lateral loads.Using micro camera,acoustic emission(AE)system,and infrared thermal imager,the AE characteristics and thermal radiation temperature migration were studied during the rockburst process.Then,the failure mode and damage evolution of the surrounding rock were analyzed.The results demonstrate that increasing the lateral load can first increase and then reduce the bearing capacity of the hole.In this experiment,the hole failure process could be divided into four periods:quiet,particle ejection,stability failure and collapse.Correspondingly,the AE signals evolved from a calm stage,to have intermittent appearance;then,they were continuous with a sudden increase,and finally increased dramatically.The failure of the surrounding rock was mainly tensile failure,while shear failure tended to first increase and then decrease.Meanwhile,damage to the hole increased gradually during the particle ejection period,whereas damage to the rockburst mainly occurred in the stability failure period.The thermal radiation temperature migration exhibited warming in shallow parts,inward expansion,cooling in the shallow parts with free surface heating,inward expansion,a sudden rise in temperature of the rockburst pits,and finally specimen failure.The initial reinforcement support should fully contribute to surface support.Furthermore,an appropriate tensile capacity and good energy absorption capacity should be established in support systems for high-stress roadways.展开更多
To examine the effect of myogenin gene on the differentiation of bovine skeletal muscle satellite cell, we constructed small interfering RNA plasmid vector to obtain myogenin knockdown bovine skeletal muscle cells, th...To examine the effect of myogenin gene on the differentiation of bovine skeletal muscle satellite cell, we constructed small interfering RNA plasmid vector to obtain myogenin knockdown bovine skeletal muscle cells, then used cell transfection, real time RCR and Western Blot to detect the influence of myogenin to cell differentiation. Results showed that the knockdown of myogenin significantly decreased its expression and other muscle-specific genes. Compared to the control, it could differentiate into few myotubes when challenged by low serum in the medium. These findings provided an important theoretical basis for further explore of the genetic mechanism in adult skeletal muscle, the remedy of muscle injuries and the cultivation of high-yield transgenic cattle.展开更多
Since the diccovery of neural stem cells(NSCs)in the embryonic and adult mammalian central nerous system,it provided novel ideas forneurogenesis as the potential of proliferation and differentiation of NSCs.One of the...Since the diccovery of neural stem cells(NSCs)in the embryonic and adult mammalian central nerous system,it provided novel ideas forneurogenesis as the potential of proliferation and differentiation of NSCs.One of the ways to promote the clinical application of neural stem cells(NSCs)is searching effective methods which regulate the proliferation and differentiation.This is also a problem urgently to be solved in medical field.Plenty of earlier studies have shown that traditional chinese medicine can promote the proliferation and differentiation of NSCs by regulating the related signaling pathway in vivo and in vitro.The reports of Chinese and foreign literatures on regulating the proliferation and differentiation of neural stem cells in recent ten years and their target and signaling pathways is analyzed in this review.The traditional chinese medicine regulate proliferation and differentiation of NSCs by the signaling pathways of Notch,PI3K/Akt,Wnt/β-catenin,and GFs.And,those signaling pathways have cross-talk in the regulation progress.Moreover,some traditional Chinese medicine,such as astragalus,has a variety of active ingredients to regulate proliferation and differentiation of NSCs through different signaling pathways.However,to accelerate the clinical application of neural stem cells,the studies aboutthe proliferation and differentiation of NSCs and Chinese medicine should be further deepened,the mechanism of multiple targets and the comprehensive regulation function of traditional Chinese medicine should be clarified.展开更多
Objective To explore the value of contrast-enhanced ultrasound(CEUS)for predicting differentiation degree of hepatocellular carcinoma(HCC).Methods Totally 86 HCC patients confirmed by postoperative pathology were retr...Objective To explore the value of contrast-enhanced ultrasound(CEUS)for predicting differentiation degree of hepatocellular carcinoma(HCC).Methods Totally 86 HCC patients confirmed by postoperative pathology were retrospectively enrolled and divided into poorly differentiated,moderately differentiated and highly differentiated groups according to postoperative Edmondson-Steiner grading.Preoperative CEUS parameters were compared among groups,and binary logistic regression was used to analyze CEUS-related independent predictors of HCC with different differentiation.The receiver operating characteristic curves of parameters being significant different among groups were drawn,the areas under the curve(AUC)were calculated,and the efficacy for predicting HCC with different differentiation degree was evaluated.Results There were 29 cases in poorly differentiated group,37 in moderately differentiated group and 20 cases in highly differentiated group.The arrival time of contrast agent in poorly differentiated group was earlier than that in moderately and high differentiated groups(both P<0.05),while in moderately differentiated group was not significantly different with that in highly differentiated group(P>0.05).The washout grade were significantly different between each 2 groups(all P<0.05).The arrival time of contrast agent and washout grade were independent predictors of highly or poorly differentiated,moderately or poorly differentiated,moderate-highly or poorly differentiated HCC,and washout grade also was independent predictor of highly or moderately differentiated HCC(all P<0.05).The AUC of the arrival time of contrast agent for predicting highly or moderately differentiated,highly or poorly differentiated,moderately or poorly differentiated,moderate-highly or poorly differentiated HCC was 0.615,0.787,0.690 and 0.724,respectively,while of washout grade was 0.801,0.927,0.795 and 0.841,respectively.Conclusion CEUS could be used to effectively predict differentiation degree of HCC.展开更多
Aphis glycines （Hemiptera： Aphididae） is considered as a cosmopolitan pest of cultivated soybean, major difficulties in its control measures may be due to its higher genetic diversity; however, the knowledge about ...Aphis glycines （Hemiptera： Aphididae） is considered as a cosmopolitan pest of cultivated soybean, major difficulties in its control measures may be due to its higher genetic diversity; however, the knowledge about population genetic diversity of this species is limited. This study aimed to represent the genetic differentiation among different geographic populations of soybean aphid in Northeast China. In order to investigate and assess the genetic diversity, genetic differentiation, molecular variance, population structure, ecological importance and evolutionary history of A. glycines, we sequenced a fragment of one protein-coding gene, the cytochrome c oxidase I/of mitochondrial DNA gene. The results showed that four haplotypes were defined among CO 11 gene of 180 sequences of soybean aphid in Northeast China including H1 shared by all the populations. Lower haplotype diversity （Hd=0.3590± 0.0420） and nucleotide diversity （Pi=0.0012±0.0002） were observed and high gene flow was detected in every two populations, while most of the variation （80.81%） arose from variability within A. glycines from individuals. Low genetic differentiation and high gene flow （Nm=2.106） indicated a high migration rate between the populations, which might reveal that gene flow in different geographic populations did not affect by geographical distance. The phylogenetic tree and the haplotype network ofA. glycines were obtained based on sequences of CO Ⅱ gene, there were no significant genealogical branches or clusters recognized in NJ tree, and no clear distribution, delineation of haplotypes were demonstrated in the haplotype network according to geographical location. This study rejected the vicariance hypothesis： geographic isolation could be a barrier and it restricted A. glycines gene flow among 10 populations.展开更多
The ventral quadrant of the tracheal epithelium of the hamster,about one fourth of tracheal mucosa, was denuded by a venous needle reformed.The stains were made with HE, PAS, and PAS-anti Brdu immunohis-tochemic techn...The ventral quadrant of the tracheal epithelium of the hamster,about one fourth of tracheal mucosa, was denuded by a venous needle reformed.The stains were made with HE, PAS, and PAS-anti Brdu immunohis-tochemic technique. At the 0 h circumference cell number (CCN) was 927. 25.From 6 h post injured the viable cells changed in shapes and migrated from themargin to wound site. By 24 h the wound area was completely covered by a sin-gle layer of non-ciliated flattened cells, then an expotential increassing in cellregeneration occured in wound site by 48 h. The CCN had been restored to thelevel of control (1373), and the proliferative cell, composed of polygonal epi-dermoid metaplasia, 3～4 layers and reached a peak (338.8). The secretoryand ciliated cells appeared gradually from 72 h post injury, the epithelium re-stored to the normal epithelial architecture by one week post injury. In our pre-sent study either in control and non-injured epithelium or in all stages of woundsite about 70% of the Brdu positive cells contained small or confluent PAS posi-tive granules were observed. This fact indicated that secretory cells play a im-portant role in proliferation after mechanical injury and maintaining the normaltracheal pseudostratified epithelium.展开更多
The decreased osteoblast differentiation associated with reduced bone formation is one main cause of microgravityinduced bone loss.Our previous studies have demonstrated that microtubule actin crosslinking factor 1(MA...The decreased osteoblast differentiation associated with reduced bone formation is one main cause of microgravityinduced bone loss.Our previous studies have demonstrated that microtubule actin crosslinking factor 1(MACF1)is downregulated in association with the decreased osteoblast differentiation and bone formation under simulated microgravity conditions.These findings suggest that MACF1 is sensitive to mechanical condition and may be critical for osteoblast differentiation and bone formation.To verify this hypothesis,current study investigates the role and mechanism of MACF1 in regulatingosteoblast differentiation by adopting MACF1 knockdown(MACF1-KD)osteoblasts.The results showed that MACF1 knockdown suppressed mineralized nodules formation,alkaline phosphatase(ALP)activity,osteogenic gene expression andβ-catenin signaling transduction.Moreover,we used RNA sequencing(RNA-seq)and chromatin immunoprecipitation sequencing(ChIP-seq)to investigate further mechanism.Interestingly,we found that MACF1 sequesterd repressors of osteoblast differentiation in cytoplasm.In conclusion,MACF1 is sensitive to mechanical condition and plays key role in activatingβ-catenin signaling transduction and sequestering repressors of osteoblast differentiation,which further promotes osteoblast differentiation.展开更多
OBJECTIVE To elucidate the underlying mechanism of DMAG in proliferation inhibition and differentia⁃tion induction on acute myeloid leukemia(AML)cell line HEL.METHODS Through CCK8 assay and colony-formation assay to d...OBJECTIVE To elucidate the underlying mechanism of DMAG in proliferation inhibition and differentia⁃tion induction on acute myeloid leukemia(AML)cell line HEL.METHODS Through CCK8 assay and colony-formation assay to detect the anti-proliferative ability of DMAG on HEL cells.Cell morphological observation(including Giemsa staining assay)and flow cytometry detecting the expression of CD41/CD42b and DNA ploidy detection were performed to identify the effect of DMAG on differentiation of HEL cells.Whole-transcriptome sequencing was taken to investigate the potential molecular mechanism of anti-AML effect of DMAG.Gene Ontology(GO)and KEGG pathway analyses were performed to evaluate molecular processes and biological pathways associated with di ff erentially expressed lncRNA,mRNA,miRNA and circRNA induced by DMAG.Co-expression network analysis was implemented to characterize the differentially expressed lncRNAs,mRNAs,miRNAs and cicrRNAs induced by DMAG.RT-qPCR was used to verify the reliability of the whole-transcriptome sequencing data.RESULTS DMAG not only significantly inhibited the prolifera⁃tion of HEL cells,but also induced the differentiation of HEL cells to megakaryocytes.Whole-transcriptome sequencing showed that a total of 595 lncRNAs,64 miRNAs,4030 mRNAs and 35 circRNAs were remarkably differentially expressed during DMAG induced differentiation of HEL cells.GO and KEGG pathway analyses revealed that those dif⁃ferentially expressed non-coding RNAs were mainly involved in biological processes as diverse as metabolic pathway,apoptosis and cell cycle.Co-expression network analysis indicated that the lncRNA-miRNA-mRNA co-expression network consisted of 40 lncRNAs and 33 miRNAs and 81 mRNAs.Meanwhile,24 circRNA,22 miRNA and 65 mRNAs partook in the construction of circRNA-miRNA-mRNA co-expression network.CONCLUSION DMAG may act as a potent differenti⁃ation inducer of AML cells.展开更多
A total of 104 isolates including two Korean isolates and three Japanese isolates of Phytophthora infestans collected from Heilongjiang and Jilin Provinces from 2006 to 2008 were used to determine their mating types,m...A total of 104 isolates including two Korean isolates and three Japanese isolates of Phytophthora infestans collected from Heilongjiang and Jilin Provinces from 2006 to 2008 were used to determine their mating types,metalaxyl resistance,and RAPD genotypes.All the isolates of P.infestans collected from Heilongjiang and Jilin Provinces belonged to A 1 mating type,and no A 2 mating type was detected.Frequencies of metalaxyl resistant isolates were 94.4%,47.8% and 75.0% in 2006,2007 and 2008,respectively.Accord...展开更多
An excellent Lonicera edulis strain, L1-8 that was bred by Northeast Institute of Geography and Agro-ecology, Chinese Academy of Sciences, was used as material in this research. The axillary buds of its dormant branch...An excellent Lonicera edulis strain, L1-8 that was bred by Northeast Institute of Geography and Agro-ecology, Chinese Academy of Sciences, was used as material in this research. The axillary buds of its dormant branches were used as explants. A fourfactor and four-level orthogonal test was designed in order to choose the best differentiation medium for providing the technical support of Lonicera edulis micropropagation. The results showed that the culture medium and concentration of 6-BA were the main factors, and the best differentiation condition was MS culture medium containing 2.0 mg · L-1 6-BA, 0.3 mg · L-1 IBA and 1.5 mg · L-1 GA3.展开更多
In order to slove the large-scale nonlinear programming （NLP） problems efficiently, an efficient optimization algorithm based on reduced sequential quadratic programming （rSQP） and automatic differentiation （AD）...In order to slove the large-scale nonlinear programming （NLP） problems efficiently, an efficient optimization algorithm based on reduced sequential quadratic programming （rSQP） and automatic differentiation （AD） is presented in this paper. With the characteristics of sparseness, relatively low degrees of freedom and equality constraints utilized, the nonlinear programming problem is solved by improved rSQP solver. In the solving process, AD technology is used to obtain accurate gradient information. The numerical results show that the combined algorithm, which is suitable for large-scale process optimization problems, can calculate more efficiently than rSQP itself.展开更多
The experiment was designed to study effects of retinoic acid and ascorbic acid on differentiation of mouse embryonic stem cells to cardiomyocytes. Embryonic bodies （EB） were developed from mESC in suspension cultur...The experiment was designed to study effects of retinoic acid and ascorbic acid on differentiation of mouse embryonic stem cells to cardiomyocytes. Embryonic bodies （EB） were developed from mESC in suspension culture, different levels of concentration of retinoic acid and ascorbic acid were used to determine the optimal conditions for EB formation. The results showed that the optimal concentrations were 10.9 mol. L-1 and 0.1 mg. mL-1 for retinoic acid and ascorbic acids, respectively. 50% of EB which was significantly （p〈0.05） different from the control group developed to cardiomyocytes. In conclusion, rctinoic acid and ascorbic acid had strong ability to promote cardiomyocyte differentiation of mouse embryonic stem cells. 10-9 mol. L-1 retinoic acid and 0.10 mg. mL-1 ascorbic acids were recommended to induce differentiation of mouse ES ceUs toward cardiomyocytes.展开更多
Climate sequences can be applied to defining sensitive climate zones, and then the mining of spatio-temporal teleconnection patterns is useful for learning from the past and preparing for the future. However, scale-de...Climate sequences can be applied to defining sensitive climate zones, and then the mining of spatio-temporal teleconnection patterns is useful for learning from the past and preparing for the future. However, scale-dependency in this kind of pattern is still not well handled by existing work. Therefore, in this study, the multi-scale regionalization is embedded into the spatio-temporal teleconnection pattern mining between anomalous sea and land climatic events. A modified scale-space clustering algorithm is first developed to group climate sequences into multi-scale climate zones. Then, scale variance analysis method is employed to identify climate zones at characteristic scales, indicating the main characteristics of geographical phenomena. Finally, by using the climate zones identified at characteristic scales, a time association rule mining algorithm based on sliding time windows is employed to discover spatio-temporal teleconnection patterns. Experiments on sea surface temperature, sea level pressure, land precipitation and land temperature datasets show that many patterns obtained by the multi-scale approach are coincident with prior knowledge, indicating that this method is effective and reasonable. In addition, some unknown teleconnection patterns discovered from the multi-scale approach can be further used to guide the prediction of land climate.展开更多
A new numerical differentiation method with local opti- mum by data segmentation is proposed. The segmentation of data is based on the second derivatives computed by a Fourier devel- opment method. A filtering process...A new numerical differentiation method with local opti- mum by data segmentation is proposed. The segmentation of data is based on the second derivatives computed by a Fourier devel- opment method. A filtering process is used to achieve acceptable segmentation. Numerical results are presented by using the data segmentation method, compared with the regularization method. For further investigation, the proposed algorithm is applied to the resistance capacitance （RC） networks identification problem, and improvements of the result are obtained by using this algorithm.展开更多
OBJECTIVE To investigate the inhibitory effect of scutellarin on the self-renewal and differentiation of HT-29 cells-derived cancer stem-like cells(HT-29CSC)in vitro and in vivo,and to explore its mechanism.METHODS Th...OBJECTIVE To investigate the inhibitory effect of scutellarin on the self-renewal and differentiation of HT-29 cells-derived cancer stem-like cells(HT-29CSC)in vitro and in vivo,and to explore its mechanism.METHODS The effect of scutellarin on the growth of HT-29CSC was determined by 3D Culture assay.The effect of scutellarin on growth and transformation of HT-29CSC was probed by soft agar colony formation assay.The effect of scutellarin on the differentiation of HT-29CSC was determined by serum induction differentiation assay in vitro.The effects of scutellarin on the expressions of marker gene Lgr5,target gene c-Myc,proliferation gene CK20 and Nanog gene were measured by quantitative real-time RT-PCR.Investigate the effect of scutellarin on the expression of c-Myc,Gli1,and Lgr5 protein by Western blotting.A subcutaneous xenograft model of colon cancer in nude mice was established and administered by intraperitoneal injection.The change of body weight and tumor size of nude mice were observed every two days.Investi⁃gate the effects of scutellarin on the growth of xenograft tumors in nude mice.The expression of CD133,Lgr5,Gli1,Ptch1,c-Myc,Ki67,CK20,Nanog gene in tumors were measured by quantitative real-time RT-PCR.The expression of c-Myc,Gli1,Lgr5,CD133,Ki67 protein were measured by Western blotting.RESULTS Scutellarin can inhibit the growth of HT-29CSC in 3D culture.Compared with the solvent control group,scutellarin can significantly inhibit the growth and transformation and differentiation of HT-29CSC in vitro(P<0.01).The expression levels of marker genes Lgr5,target gene c-Myc,proliferation gene CK20 and Nanog in HT-29CSC were down-regulated by scutellarin.Scutellarin can reduce the expression of c-Myc,Gli1,and Lgr5 protein in HT-29CSC.Scutellarin can inhibit the growth of colon cancer xenografts,lower CD133,Lgr5,Gli1,Ptch1,c-Myc,Ki67,CK20,and Nanog mRNA level of xenograft tumors,reduce the expression of c-Myc,Gli1,Lgr5,CD133,and Ki67 protein of xenograft tumors in nude mice.CONCLUSION Scutellarin,which is the main component of scutellaria barbata,can inhibit the differentiation of HT-29CSC and the mechanism is to inhibit the activity of Hedgehog signaling pathway.展开更多
In this paper,an improved spatio-temporal alignment measurement method is presented to address the inertial matching measurement of hull deformation under the coexistence of time delay and large misalignment angle.Lar...In this paper,an improved spatio-temporal alignment measurement method is presented to address the inertial matching measurement of hull deformation under the coexistence of time delay and large misalignment angle.Large misalignment angle and time delay often occur simultaneously and bring great challenges to the accurate measurement of hull deformation in space and time.The proposed method utilizes coarse alignment with large misalignment angle and time delay estimation of inertial measurement unit modeling to establish a brand-new spatiotemporal aligned hull deformation measurement model.In addition,two-step loop control is designed to ensure the accurate description of dynamic deformation angle and static deformation angle by the time-space alignment method of hull deformation.The experiments illustrate that the proposed method can effectively measure the hull deformation angle when time delay and large misalignment angle coexist.展开更多
High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high efficiency.However,it...High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high efficiency.However,it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment swarm.To address these challenges,this work presents a warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography.Firstly,background difference algorithm is utilized to extract the center and area of each fragment in the image sequence.Subsequently,a multi-object tracking(MOT)algorithm using Kalman filtering and Hungarian optimal assignment is developed to realize real-time and robust trajectories tracking of fragment swarm.To reconstruct 3D motion trajectories,a global stereo trajectories matching strategy is presented,which takes advantages of epipolar constraint and continuity constraint to correctly retrieve stereo correspondence followed by 3D trajectories refinement using polynomial fitting.Finally,the simulation and experimental results demonstrate that the proposed method can accurately track the motion trajectories and reconstruct the spatio-temporal distribution of 1.0×10^(3)fragments in a field of view(FOV)of 3.2 m×2.5 m,and the accuracy of the velocity estimation can achieve 98.6%.展开更多
To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage p...To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage probability leveraging spatio-temporal finite multilayer fragments distribution and the target damage assessment algorithm based on cloud model theory.Drawing on the spatial dispersion characteristics of fragments of projectile proximity explosion,we divide into a finite number of fragments distribution planes based on the time series in space,set up a fragment layer dispersion model grounded in the time series and intersection criterion for determining the effective penetration of each layer of fragments into the target.Building on the precondition that the multilayer fragments of the time series effectively assail the target,we also establish the damage criterion of the perforation and penetration damage and deduce the damage probability calculation model.Taking the damage probability of the fragment layer in the spatio-temporal sequence to the target as the input state variable,we introduce cloud model theory to research the target damage assessment method.Combining the equivalent simulation experiment,the scientific and rational nature of the proposed method were validated through quantitative calculations and comparative analysis.展开更多
基金supported by grants from the Liaoning Province Excellent Talent Program Project(XLYC1902031)Dalian Science and Technology Talent Innovation Plan Grant(2022RG18)Basic Research Project of the Department of Education of Liaoning Province(LJKQZ20222395)。
文摘Objective Cerebral palsy(CP)is a prevalent neurodevelopmental disorder acquired during the perinatal period,with periventricular white matter injury(PWMI)serving as its primary pathological hallmark.PWMI is characterized by the loss of oligodendrocytes(OLs)and the disintegration of myelin sheaths,leading to impaired neural connectivity and motor dysfunction.Neural stem cells(NSCs)represent a promising regenerative source for replenishing lost OLs;however,conventional twodimensional(2D)in vitro culture systems lack the three-dimensional(3D)physiological microenvironment.Microfluidic chip technology has emerged as a powerful tool to overcome this limitation by enabling precise spatial and temporal control over 3D microenvironmental conditions,including the establishment of stable concentration gradients of bioactive molecules.Catalpol,an iridoid glycoside derived from traditional medicinal plants,exhibits dual antioxidant and anti-apoptotic properties.Despite its therapeutic potential,the capacity of catalpol to drive NSC differentiation toward OLs under biomimetic 3D conditions,as well as the underlying molecular mechanisms,remains poorly understood.This study aims to develop a microfluidic-based 3D biomimetic platform to systematically investigate the concentration-dependent effects of catalpol on promoting NSCs-to-OLs differentiation and to elucidate the role of the caveolin-1(Cav-1)signaling pathway in this process.Methods We developed a novel multiplexed microfluidic device featuring parallel microchannels with integrated gradient generators capable of establishing and maintaining precise linear concentration gradients(0-3 g/L catalpol)across 3D NSCs cultures.This platform facilitated the continuous perfusion culture of NSC-derived 3D spheroids,mimicking the dynamic in vivo microenvironment.Real-time cell viability was assessed using Calcein-AM/propidium iodide(PI)dual staining,with fluorescence imaging quantifying live/dead cell ratios.Oligodendrocyte differentiation was evaluated through quantitative reverse transcription polymerase chain reaction(qRT-PCR)for MBP and SOX10 gene expression,complemented by immunofluorescence staining to visualize corresponding protein changes.To dissect the molecular mechanism,the Cav-1-specific pharmacological inhibitor methyl‑β‑cyclodextrin(MCD)was employed to perturb the pathway,and its effects on differentiation markers were analyzed.Results Catalpol demonstrated excellent biocompatibility,with cell viability exceeding 96%across the entire tested concentration range(0-3 g/L),confirming its non-cytotoxic nature.At the optimal concentration of 0-3 g/L,catalpol significantly upregulated both MBP and SOX10 expression(P<0.05,P<0.01),indicating robust promotion of oligodendroglial differentiation.Intriguingly,Cav-1 mRNA expression was progressively downregulated during NSC differentiation into OLs.Further inhibition of Cav-1 with MCD further enhanced this effect,leading to a statistically significant increase in OL-specific gene expression(P<0.05,P<0.01),suggesting Cav-1 acts as a negative regulator of OLs differentiation.Conclusion This study established an integrated microfluidic gradient chip-3D NSC spheroid culture system,which combines the advantages of precise chemical gradient control with physiologically relevant 3D cell culture.The findings demonstrate that 3 g/L catalpol effectively suppresses Cav-1 signaling to drive NSC differentiation into functional OLs.This work not only provides novel insights into the Cav-1-dependent mechanisms of myelination but also delivers a scalable technological platform for future research on remyelination therapies,with potential applications in cerebral palsy and other white matter disorders.The platform’s modular design permits adaptation for screening other neurogenic compounds or investigating additional signaling pathways involved in OLs maturation.
基金Supported by Natural Science Foundation of Guangdong Province in China(2018KTSCX161)。
文摘The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic functions in the unit ball by radial derivative.Then we extend the Sharma's results.
基金Project(2017YFC0603003)supported by the National Key Research and Development Project of ChinaProjects(51974009,51674008)supported by the National Natural Science Foundation of China+3 种基金Project(201904a07020010)supported by the Key Research and Development Program of Anhui Province,ChinaProject(2018D187)supported by the Leading Talent Project of Anhui“Special Support Program”,Anhui Provincial Academic and Technology Leaders Research Activities Funding,ChinaProject(gxbjZD2016051)supported by the Excellence Talent Training Program of High School,ChinaProject(2019CX2008)supported by the Graduate Innovation Fund of Anhui University of Science and Technology,China。
文摘To study the mechanism of rockburst and its spatio-temporal evolution criterion,a rockburst simulation experiment was performed on granite specimens,each with a prefabricated circular hole,under different lateral loads.Using micro camera,acoustic emission(AE)system,and infrared thermal imager,the AE characteristics and thermal radiation temperature migration were studied during the rockburst process.Then,the failure mode and damage evolution of the surrounding rock were analyzed.The results demonstrate that increasing the lateral load can first increase and then reduce the bearing capacity of the hole.In this experiment,the hole failure process could be divided into four periods:quiet,particle ejection,stability failure and collapse.Correspondingly,the AE signals evolved from a calm stage,to have intermittent appearance;then,they were continuous with a sudden increase,and finally increased dramatically.The failure of the surrounding rock was mainly tensile failure,while shear failure tended to first increase and then decrease.Meanwhile,damage to the hole increased gradually during the particle ejection period,whereas damage to the rockburst mainly occurred in the stability failure period.The thermal radiation temperature migration exhibited warming in shallow parts,inward expansion,cooling in the shallow parts with free surface heating,inward expansion,a sudden rise in temperature of the rockburst pits,and finally specimen failure.The initial reinforcement support should fully contribute to surface support.Furthermore,an appropriate tensile capacity and good energy absorption capacity should be established in support systems for high-stress roadways.
基金Supported by the Ministry of Agricultural Nuarture of New Varieties Genetically Modified Organisms Significant Special Funding (2008ZX08007-002)
文摘To examine the effect of myogenin gene on the differentiation of bovine skeletal muscle satellite cell, we constructed small interfering RNA plasmid vector to obtain myogenin knockdown bovine skeletal muscle cells, then used cell transfection, real time RCR and Western Blot to detect the influence of myogenin to cell differentiation. Results showed that the knockdown of myogenin significantly decreased its expression and other muscle-specific genes. Compared to the control, it could differentiate into few myotubes when challenged by low serum in the medium. These findings provided an important theoretical basis for further explore of the genetic mechanism in adult skeletal muscle, the remedy of muscle injuries and the cultivation of high-yield transgenic cattle.
基金supported by National Natural Science Foundation of China(81473549)Fundamental Research Funds for Central Universities(XDJK2017E158)
文摘Since the diccovery of neural stem cells(NSCs)in the embryonic and adult mammalian central nerous system,it provided novel ideas forneurogenesis as the potential of proliferation and differentiation of NSCs.One of the ways to promote the clinical application of neural stem cells(NSCs)is searching effective methods which regulate the proliferation and differentiation.This is also a problem urgently to be solved in medical field.Plenty of earlier studies have shown that traditional chinese medicine can promote the proliferation and differentiation of NSCs by regulating the related signaling pathway in vivo and in vitro.The reports of Chinese and foreign literatures on regulating the proliferation and differentiation of neural stem cells in recent ten years and their target and signaling pathways is analyzed in this review.The traditional chinese medicine regulate proliferation and differentiation of NSCs by the signaling pathways of Notch,PI3K/Akt,Wnt/β-catenin,and GFs.And,those signaling pathways have cross-talk in the regulation progress.Moreover,some traditional Chinese medicine,such as astragalus,has a variety of active ingredients to regulate proliferation and differentiation of NSCs through different signaling pathways.However,to accelerate the clinical application of neural stem cells,the studies aboutthe proliferation and differentiation of NSCs and Chinese medicine should be further deepened,the mechanism of multiple targets and the comprehensive regulation function of traditional Chinese medicine should be clarified.
文摘Objective To explore the value of contrast-enhanced ultrasound(CEUS)for predicting differentiation degree of hepatocellular carcinoma(HCC).Methods Totally 86 HCC patients confirmed by postoperative pathology were retrospectively enrolled and divided into poorly differentiated,moderately differentiated and highly differentiated groups according to postoperative Edmondson-Steiner grading.Preoperative CEUS parameters were compared among groups,and binary logistic regression was used to analyze CEUS-related independent predictors of HCC with different differentiation.The receiver operating characteristic curves of parameters being significant different among groups were drawn,the areas under the curve(AUC)were calculated,and the efficacy for predicting HCC with different differentiation degree was evaluated.Results There were 29 cases in poorly differentiated group,37 in moderately differentiated group and 20 cases in highly differentiated group.The arrival time of contrast agent in poorly differentiated group was earlier than that in moderately and high differentiated groups(both P<0.05),while in moderately differentiated group was not significantly different with that in highly differentiated group(P>0.05).The washout grade were significantly different between each 2 groups(all P<0.05).The arrival time of contrast agent and washout grade were independent predictors of highly or poorly differentiated,moderately or poorly differentiated,moderate-highly or poorly differentiated HCC,and washout grade also was independent predictor of highly or moderately differentiated HCC(all P<0.05).The AUC of the arrival time of contrast agent for predicting highly or moderately differentiated,highly or poorly differentiated,moderately or poorly differentiated,moderate-highly or poorly differentiated HCC was 0.615,0.787,0.690 and 0.724,respectively,while of washout grade was 0.801,0.927,0.795 and 0.841,respectively.Conclusion CEUS could be used to effectively predict differentiation degree of HCC.
基金Supported by the Special funds for Construction of Modern Agricultural Technology System(CARS-04)Public Welfare Industry(Agriculture)Special Fund(201103002)
文摘Aphis glycines （Hemiptera： Aphididae） is considered as a cosmopolitan pest of cultivated soybean, major difficulties in its control measures may be due to its higher genetic diversity; however, the knowledge about population genetic diversity of this species is limited. This study aimed to represent the genetic differentiation among different geographic populations of soybean aphid in Northeast China. In order to investigate and assess the genetic diversity, genetic differentiation, molecular variance, population structure, ecological importance and evolutionary history of A. glycines, we sequenced a fragment of one protein-coding gene, the cytochrome c oxidase I/of mitochondrial DNA gene. The results showed that four haplotypes were defined among CO 11 gene of 180 sequences of soybean aphid in Northeast China including H1 shared by all the populations. Lower haplotype diversity （Hd=0.3590± 0.0420） and nucleotide diversity （Pi=0.0012±0.0002） were observed and high gene flow was detected in every two populations, while most of the variation （80.81%） arose from variability within A. glycines from individuals. Low genetic differentiation and high gene flow （Nm=2.106） indicated a high migration rate between the populations, which might reveal that gene flow in different geographic populations did not affect by geographical distance. The phylogenetic tree and the haplotype network ofA. glycines were obtained based on sequences of CO Ⅱ gene, there were no significant genealogical branches or clusters recognized in NJ tree, and no clear distribution, delineation of haplotypes were demonstrated in the haplotype network according to geographical location. This study rejected the vicariance hypothesis： geographic isolation could be a barrier and it restricted A. glycines gene flow among 10 populations.
文摘The ventral quadrant of the tracheal epithelium of the hamster,about one fourth of tracheal mucosa, was denuded by a venous needle reformed.The stains were made with HE, PAS, and PAS-anti Brdu immunohis-tochemic technique. At the 0 h circumference cell number (CCN) was 927. 25.From 6 h post injured the viable cells changed in shapes and migrated from themargin to wound site. By 24 h the wound area was completely covered by a sin-gle layer of non-ciliated flattened cells, then an expotential increassing in cellregeneration occured in wound site by 48 h. The CCN had been restored to thelevel of control (1373), and the proliferative cell, composed of polygonal epi-dermoid metaplasia, 3～4 layers and reached a peak (338.8). The secretoryand ciliated cells appeared gradually from 72 h post injury, the epithelium re-stored to the normal epithelial architecture by one week post injury. In our pre-sent study either in control and non-injured epithelium or in all stages of woundsite about 70% of the Brdu positive cells contained small or confluent PAS posi-tive granules were observed. This fact indicated that secretory cells play a im-portant role in proliferation after mechanical injury and maintaining the normaltracheal pseudostratified epithelium.
基金supported by the National Natural Science Foundation of China ( 81772017,31570940)Young Talent Fund of University Association for Science and Technology in Shaanxi,China ( 20170401)Supported by Natural Science Basic Research Plan in Shaanxi Province of China ( 2018JM3040)
文摘The decreased osteoblast differentiation associated with reduced bone formation is one main cause of microgravityinduced bone loss.Our previous studies have demonstrated that microtubule actin crosslinking factor 1(MACF1)is downregulated in association with the decreased osteoblast differentiation and bone formation under simulated microgravity conditions.These findings suggest that MACF1 is sensitive to mechanical condition and may be critical for osteoblast differentiation and bone formation.To verify this hypothesis,current study investigates the role and mechanism of MACF1 in regulatingosteoblast differentiation by adopting MACF1 knockdown(MACF1-KD)osteoblasts.The results showed that MACF1 knockdown suppressed mineralized nodules formation,alkaline phosphatase(ALP)activity,osteogenic gene expression andβ-catenin signaling transduction.Moreover,we used RNA sequencing(RNA-seq)and chromatin immunoprecipitation sequencing(ChIP-seq)to investigate further mechanism.Interestingly,we found that MACF1 sequesterd repressors of osteoblast differentiation in cytoplasm.In conclusion,MACF1 is sensitive to mechanical condition and plays key role in activatingβ-catenin signaling transduction and sequestering repressors of osteoblast differentiation,which further promotes osteoblast differentiation.
基金Application and Basic Research Project of Sichuan Technology Department(2019YJ0484)Application and Basic Research Project of Luzhou-Southwest Medical University(2018LZXNYD-ZK31)
文摘OBJECTIVE To elucidate the underlying mechanism of DMAG in proliferation inhibition and differentia⁃tion induction on acute myeloid leukemia(AML)cell line HEL.METHODS Through CCK8 assay and colony-formation assay to detect the anti-proliferative ability of DMAG on HEL cells.Cell morphological observation(including Giemsa staining assay)and flow cytometry detecting the expression of CD41/CD42b and DNA ploidy detection were performed to identify the effect of DMAG on differentiation of HEL cells.Whole-transcriptome sequencing was taken to investigate the potential molecular mechanism of anti-AML effect of DMAG.Gene Ontology(GO)and KEGG pathway analyses were performed to evaluate molecular processes and biological pathways associated with di ff erentially expressed lncRNA,mRNA,miRNA and circRNA induced by DMAG.Co-expression network analysis was implemented to characterize the differentially expressed lncRNAs,mRNAs,miRNAs and cicrRNAs induced by DMAG.RT-qPCR was used to verify the reliability of the whole-transcriptome sequencing data.RESULTS DMAG not only significantly inhibited the prolifera⁃tion of HEL cells,but also induced the differentiation of HEL cells to megakaryocytes.Whole-transcriptome sequencing showed that a total of 595 lncRNAs,64 miRNAs,4030 mRNAs and 35 circRNAs were remarkably differentially expressed during DMAG induced differentiation of HEL cells.GO and KEGG pathway analyses revealed that those dif⁃ferentially expressed non-coding RNAs were mainly involved in biological processes as diverse as metabolic pathway,apoptosis and cell cycle.Co-expression network analysis indicated that the lncRNA-miRNA-mRNA co-expression network consisted of 40 lncRNAs and 33 miRNAs and 81 mRNAs.Meanwhile,24 circRNA,22 miRNA and 65 mRNAs partook in the construction of circRNA-miRNA-mRNA co-expression network.CONCLUSION DMAG may act as a potent differenti⁃ation inducer of AML cells.
基金Supported by Scientific Research Fund of Northeast Agricultural UniversityScience Foundation and Ministry of EducationReturned Overseas Students to Start-up Foundation (210150)
文摘A total of 104 isolates including two Korean isolates and three Japanese isolates of Phytophthora infestans collected from Heilongjiang and Jilin Provinces from 2006 to 2008 were used to determine their mating types,metalaxyl resistance,and RAPD genotypes.All the isolates of P.infestans collected from Heilongjiang and Jilin Provinces belonged to A 1 mating type,and no A 2 mating type was detected.Frequencies of metalaxyl resistant isolates were 94.4%,47.8% and 75.0% in 2006,2007 and 2008,respectively.Accord...
基金Supported by the State Bureau of Foreign Experts 2013 Annual Talent Introduction of Foreign Technology,Project Management(20132300046)
文摘An excellent Lonicera edulis strain, L1-8 that was bred by Northeast Institute of Geography and Agro-ecology, Chinese Academy of Sciences, was used as material in this research. The axillary buds of its dormant branches were used as explants. A fourfactor and four-level orthogonal test was designed in order to choose the best differentiation medium for providing the technical support of Lonicera edulis micropropagation. The results showed that the culture medium and concentration of 6-BA were the main factors, and the best differentiation condition was MS culture medium containing 2.0 mg · L-1 6-BA, 0.3 mg · L-1 IBA and 1.5 mg · L-1 GA3.
文摘In order to slove the large-scale nonlinear programming （NLP） problems efficiently, an efficient optimization algorithm based on reduced sequential quadratic programming （rSQP） and automatic differentiation （AD） is presented in this paper. With the characteristics of sparseness, relatively low degrees of freedom and equality constraints utilized, the nonlinear programming problem is solved by improved rSQP solver. In the solving process, AD technology is used to obtain accurate gradient information. The numerical results show that the combined algorithm, which is suitable for large-scale process optimization problems, can calculate more efficiently than rSQP itself.
基金Supported by the Scientifi c Research Foundation for Doctors of Northeast Agricultural University(2012RCB27)Open Projects of Key Laboratory of Animal Genetics,Breeding and Reproduction,College of Heilongjiang Province(GXZDSYS-2012-07)
文摘The experiment was designed to study effects of retinoic acid and ascorbic acid on differentiation of mouse embryonic stem cells to cardiomyocytes. Embryonic bodies （EB） were developed from mESC in suspension culture, different levels of concentration of retinoic acid and ascorbic acid were used to determine the optimal conditions for EB formation. The results showed that the optimal concentrations were 10.9 mol. L-1 and 0.1 mg. mL-1 for retinoic acid and ascorbic acids, respectively. 50% of EB which was significantly （p〈0.05） different from the control group developed to cardiomyocytes. In conclusion, rctinoic acid and ascorbic acid had strong ability to promote cardiomyocyte differentiation of mouse embryonic stem cells. 10-9 mol. L-1 retinoic acid and 0.10 mg. mL-1 ascorbic acids were recommended to induce differentiation of mouse ES ceUs toward cardiomyocytes.
基金Projects(41601424,41171351)supported by the National Natural Science Foundation of ChinaProject(2012CB719906)supported by the National Basic Research Program of China(973 Program)+2 种基金Project(14JJ1007)supported by the Hunan Natural Science Fund for Distinguished Young Scholars,ChinaProject(2017M610486)supported by the China Postdoctoral Science FoundationProjects(2017YFB0503700,2017YFB0503601)supported by the National Key Research and Development Foundation of China
文摘Climate sequences can be applied to defining sensitive climate zones, and then the mining of spatio-temporal teleconnection patterns is useful for learning from the past and preparing for the future. However, scale-dependency in this kind of pattern is still not well handled by existing work. Therefore, in this study, the multi-scale regionalization is embedded into the spatio-temporal teleconnection pattern mining between anomalous sea and land climatic events. A modified scale-space clustering algorithm is first developed to group climate sequences into multi-scale climate zones. Then, scale variance analysis method is employed to identify climate zones at characteristic scales, indicating the main characteristics of geographical phenomena. Finally, by using the climate zones identified at characteristic scales, a time association rule mining algorithm based on sliding time windows is employed to discover spatio-temporal teleconnection patterns. Experiments on sea surface temperature, sea level pressure, land precipitation and land temperature datasets show that many patterns obtained by the multi-scale approach are coincident with prior knowledge, indicating that this method is effective and reasonable. In addition, some unknown teleconnection patterns discovered from the multi-scale approach can be further used to guide the prediction of land climate.
基金supported by the National Basic Research Program of China(2011CB013103)
文摘A new numerical differentiation method with local opti- mum by data segmentation is proposed. The segmentation of data is based on the second derivatives computed by a Fourier devel- opment method. A filtering process is used to achieve acceptable segmentation. Numerical results are presented by using the data segmentation method, compared with the regularization method. For further investigation, the proposed algorithm is applied to the resistance capacitance （RC） networks identification problem, and improvements of the result are obtained by using this algorithm.
基金National Natural Science Foundation of China(8157381381173598)+1 种基金Excellent Talent Program of Chengdu University of Traditional Chinese Medicine(YXRC2019002)Fund of Scientific Research Innovation Team Construction in Sichuan Provincial University(18TD0017)
文摘OBJECTIVE To investigate the inhibitory effect of scutellarin on the self-renewal and differentiation of HT-29 cells-derived cancer stem-like cells(HT-29CSC)in vitro and in vivo,and to explore its mechanism.METHODS The effect of scutellarin on the growth of HT-29CSC was determined by 3D Culture assay.The effect of scutellarin on growth and transformation of HT-29CSC was probed by soft agar colony formation assay.The effect of scutellarin on the differentiation of HT-29CSC was determined by serum induction differentiation assay in vitro.The effects of scutellarin on the expressions of marker gene Lgr5,target gene c-Myc,proliferation gene CK20 and Nanog gene were measured by quantitative real-time RT-PCR.Investigate the effect of scutellarin on the expression of c-Myc,Gli1,and Lgr5 protein by Western blotting.A subcutaneous xenograft model of colon cancer in nude mice was established and administered by intraperitoneal injection.The change of body weight and tumor size of nude mice were observed every two days.Investi⁃gate the effects of scutellarin on the growth of xenograft tumors in nude mice.The expression of CD133,Lgr5,Gli1,Ptch1,c-Myc,Ki67,CK20,Nanog gene in tumors were measured by quantitative real-time RT-PCR.The expression of c-Myc,Gli1,Lgr5,CD133,Ki67 protein were measured by Western blotting.RESULTS Scutellarin can inhibit the growth of HT-29CSC in 3D culture.Compared with the solvent control group,scutellarin can significantly inhibit the growth and transformation and differentiation of HT-29CSC in vitro(P<0.01).The expression levels of marker genes Lgr5,target gene c-Myc,proliferation gene CK20 and Nanog in HT-29CSC were down-regulated by scutellarin.Scutellarin can reduce the expression of c-Myc,Gli1,and Lgr5 protein in HT-29CSC.Scutellarin can inhibit the growth of colon cancer xenografts,lower CD133,Lgr5,Gli1,Ptch1,c-Myc,Ki67,CK20,and Nanog mRNA level of xenograft tumors,reduce the expression of c-Myc,Gli1,Lgr5,CD133,and Ki67 protein of xenograft tumors in nude mice.CONCLUSION Scutellarin,which is the main component of scutellaria barbata,can inhibit the differentiation of HT-29CSC and the mechanism is to inhibit the activity of Hedgehog signaling pathway.
基金supported by Beijing Insititute of Technology Research Fund Program for Young Scholars(2020X04104)。
文摘In this paper,an improved spatio-temporal alignment measurement method is presented to address the inertial matching measurement of hull deformation under the coexistence of time delay and large misalignment angle.Large misalignment angle and time delay often occur simultaneously and bring great challenges to the accurate measurement of hull deformation in space and time.The proposed method utilizes coarse alignment with large misalignment angle and time delay estimation of inertial measurement unit modeling to establish a brand-new spatiotemporal aligned hull deformation measurement model.In addition,two-step loop control is designed to ensure the accurate description of dynamic deformation angle and static deformation angle by the time-space alignment method of hull deformation.The experiments illustrate that the proposed method can effectively measure the hull deformation angle when time delay and large misalignment angle coexist.
基金Key Basic Research Project of Strengthening the Foundations Plan of China (Grant No.2019-JCJQ-ZD-360-12)National Defense Basic Scientific Research Program of China (Grant No.JCKY2021208B011)to provide fund for conducting experiments。
文摘High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high efficiency.However,it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment swarm.To address these challenges,this work presents a warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography.Firstly,background difference algorithm is utilized to extract the center and area of each fragment in the image sequence.Subsequently,a multi-object tracking(MOT)algorithm using Kalman filtering and Hungarian optimal assignment is developed to realize real-time and robust trajectories tracking of fragment swarm.To reconstruct 3D motion trajectories,a global stereo trajectories matching strategy is presented,which takes advantages of epipolar constraint and continuity constraint to correctly retrieve stereo correspondence followed by 3D trajectories refinement using polynomial fitting.Finally,the simulation and experimental results demonstrate that the proposed method can accurately track the motion trajectories and reconstruct the spatio-temporal distribution of 1.0×10^(3)fragments in a field of view(FOV)of 3.2 m×2.5 m,and the accuracy of the velocity estimation can achieve 98.6%.
基金supported by National Natural Science Foundation of China(Grant No.62073256)the Shaanxi Provincial Science and Technology Department(Grant No.2023-YBGY-342).
文摘To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage probability leveraging spatio-temporal finite multilayer fragments distribution and the target damage assessment algorithm based on cloud model theory.Drawing on the spatial dispersion characteristics of fragments of projectile proximity explosion,we divide into a finite number of fragments distribution planes based on the time series in space,set up a fragment layer dispersion model grounded in the time series and intersection criterion for determining the effective penetration of each layer of fragments into the target.Building on the precondition that the multilayer fragments of the time series effectively assail the target,we also establish the damage criterion of the perforation and penetration damage and deduce the damage probability calculation model.Taking the damage probability of the fragment layer in the spatio-temporal sequence to the target as the input state variable,we introduce cloud model theory to research the target damage assessment method.Combining the equivalent simulation experiment,the scientific and rational nature of the proposed method were validated through quantitative calculations and comparative analysis.
