期刊文献+
共找到25,187篇文章
< 1 2 250 >
每页显示 20 50 100
Utilizing spatio-temporal feature fusion in videos for detecting the fluidity of coal water slurry
1
作者 Meijie Sun Ziqi Lv +3 位作者 Zhiqiang Xu Haimei Lv Yanan Tu Weidong Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第11期1587-1597,共11页
The fluidity of coal-water slurry(CWS)is crucial for various industrial applications such as long-distance transportation,gasification,and combustion.However,there is currently a lack of rapid and accurate detection m... The fluidity of coal-water slurry(CWS)is crucial for various industrial applications such as long-distance transportation,gasification,and combustion.However,there is currently a lack of rapid and accurate detection methods for assessing CWS fluidity.This paper proposed a method for analyzing the fluidity using videos of CWS dripping processes.By integrating the temporal and spatial features of each frame in the video,a multi-cascade classifier for CWS fluidity is established.The classifier distinguishes between four levels(A,B,C,and D)based on the quality of fluidity.The preliminary classification of A and D is achieved through feature engineering and the XGBoost algorithm.Subsequently,convolutional neural networks(CNN)and long short-term memory(LSTM)are utilized to further differentiate between the B and C categories which are prone to confusion.Finally,through detailed comparative experiments,the paper demonstrates the step-by-step design process of the proposed method and the superiority of the final solution.The proposed method achieves an accuracy rate of over 90%in determining the fluidity of CWS,serving as a technical reference for future industrial applications. 展开更多
关键词 Coal water slurry spatio-temporal feature CNN-LSTM Video classification Machine vision
在线阅读 下载PDF
Warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography
2
作者 Pengyu Hu Jiangpeng Wu +3 位作者 Zhengang Yan Meng He Chao Liang Hao Bai 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第7期162-172,共11页
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
关键词 Warhead fragment measurement High speed photography Stereo vision Multi-object tracking spatio-temporal reconstruction
在线阅读 下载PDF
A cloud model target damage effectiveness assessment algorithm based on spatio-temporal sequence finite multilayer fragments dispersion
3
作者 Hanshan Li Xiaoqian Zhang Junchai Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期48-64,共17页
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
关键词 Target damage Cloud model Fragments dispersion Effectiveness assessment spatio-temporal sequence
在线阅读 下载PDF
Comparative proteomics analysis reveals the domesticated Lepista sordida primordium differentiation regulation mechanism and the subsequent different development patterns in the pileus and stipe
4
作者 Xiuqing Yang Meijie Liu +7 位作者 Yanjiao Zhang Lizhong Guo Junqi Wang Sizhu Li Yan Zhang Xiaobo Li Lili Xu Hao Yu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期3066-3082,共17页
The wild Lepista sordida is a kind of precious and rare edible fungus.An excellent strain of it by artificial domestication was obtained,which was high-yield and high in iron content.In this study,high-throughput comp... The wild Lepista sordida is a kind of precious and rare edible fungus.An excellent strain of it by artificial domestication was obtained,which was high-yield and high in iron content.In this study,high-throughput comparative proteomics was used to reveal the regulatory mechanism of its primordium differentiation in the early fruiting body formation.The mycelium before the primordium differentiation mainly expressed high levels of mitochondrial functional proteins and carbon dioxide concentration regulatory proteins.In young mushrooms,the highly expressed proteins were mainly involved in cell component generation,cell proliferation,nitrogen compound metabolism,nucleotide metabolism,glutathione metabolism,and purine metabolism.The differential regulation patterns of pileus and stipe growth to maturity were also revealed.The highly expressed proteins related to transcription,RNA splicing,the production of various organelles,DNA conformational change,nucleosome organization,protein processing,maturation and transport,and cell detoxification regulated the pileus development and maturity.The proteins related to carbohydrate and energy metabolism,large amounts of obsolete cytoplasmic parts,nutrient deprivation,and external stimuli regulated the stipe development and maturity.Multiple CAZymes regulated nutrient absorption,morphogenesis,spore production,stress response,and other life activities at different growth and development stages. 展开更多
关键词 Lepista sordida Comparative proteomics Primordial differentiation Growth and development regulation PILEUS STIPE
在线阅读 下载PDF
Spatio-temporal distribution of net primary productivity along the northeast China transect and its response to climatic change 被引量:11
5
作者 朱文泉 潘耀忠 +1 位作者 刘鑫 王爱玲 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期93-98,共6页
An improved Carnegie Ames Stanford Approach model (CASA model) was used to estimate the net primary productivity (NPP) of the Northeast China Transect (NECT) every month from 1982 to 2000. The spatial-temporal d... An improved Carnegie Ames Stanford Approach model (CASA model) was used to estimate the net primary productivity (NPP) of the Northeast China Transect (NECT) every month from 1982 to 2000. The spatial-temporal distribution of NPP along NECT and its response to climatic change were also analyzed. Results showed that the change tendency of NPP spatial distribution in NECT is quite similar to that of precipitation and their spatial correlation coefficient is up to 0.84 (P 〈 0.01). The inter-annual variation of NPP in NECT is mainly affected by the change of the aestival NPP every year, which accounts for 67.6% of the inter-annual increase in NPP and their spatial correlation coefficient is 0.95 (P 〈 0.01). The NPP in NECT is mainly cumulated between May and September, which accounts for 89.8% of the annual NPP. The NPP in summer (June to August) accounts for 65.9% of the annual NPP and is the lowest in winter. Recent climate changes have enhanced plant growth in NECT. The mean NPP increased 14.3% from 1980s to 1990s. The inter-annual linear trend of NPP is 4.6 gC·m^-2·a^-1, and the relative trend is 1.17%, which owns mainly to the increasing temperature. 展开更多
关键词 China Transect Remote sensing Net primary productivity (NPP) Climatic change spatio-temporal distribution
在线阅读 下载PDF
Population genetic diversity and regional differentiation of Chinese forest frog s (Rana chensinensis) in Heilongjiang Province 被引量:6
6
作者 肖向红 郑冬 +1 位作者 李枫 刘学东 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第1期40-42,共4页
The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields o... The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields of 8 regions in Heilongjiang Province. Totally 78 polymorphic DNA loci were amplified by 10 RAP D primers. By genetic distance analysis and phylogenetic tree reconstruction wit h the Neighbor-Joining (NJ) method the results showed that the populations of Ch inese forest frogs distributed in 8 regions existed great differentiation (Avera ge Fst=0.347, SD=0.235) while there was the paradox between geographic distances and genetic distances. Based on geographic and geological data, a hypothesis wa s posed that it is very possible that the hilly lands in the downstream of the S onghua River and the Heilong River were the center of the origin of the Chinese forest frogs in Heilongjiang Province. And mainly through the Songhua River syst em, the Chinese forest frogs dispersed into the Songneng Plain from the Sanjiang Plain whereas the Fangzheng region became a sub-center for the western dispersi on. 展开更多
关键词 Chinese forest frogs (Rana chensinensis) Population genetics Regiona l differentiation
在线阅读 下载PDF
Genetic diversity and genetic differentiation of natural populations of Pinus kesiya var. langbinanensis 被引量:6
7
作者 陈少瑜 赵文书 王炯 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期273-276,337,共4页
Genetic diversity and genetic differentiation of natural populations of Pinus kesiya var. langbinanensis were examined by means of electrophoresis technique. Analysis of 9 enzyme systems including 16 loci showed that ... Genetic diversity and genetic differentiation of natural populations of Pinus kesiya var. langbinanensis were examined by means of electrophoresis technique. Analysis of 9 enzyme systems including 16 loci showed that all the three natural popu-lations of the pine were high in genetic diversity but low in inter-population genetic differentiation. The proportion of polymorphic loci is 0.667, with each locus holding 2.13 alleles, averagely. The average expected and observed heterozygosity was 0.288 and 0.197, respectively. The gene differentiation among populations was 0.052, but the mean genetic distance was only 0.015. 展开更多
关键词 Pinus kesiya var. langbinanensis Natural population ISOZYME Genetic diversity Genetic differentiation
在线阅读 下载PDF
Genetic diversity and differentiation of the Dybowski's frog(Rana dybowskii) in Northeast China 被引量:5
8
作者 张明 贾学渊 马建章 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期239-245,I0008,共8页
The genetic diversity and population structure of the Dybowski's frog(Rana dybowskii) were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser K... The genetic diversity and population structure of the Dybowski's frog(Rana dybowskii) were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser Khingan Mountains and Changbai Mountains,China.Results showed that allele number of the 11 microsatellite loci was in the range of 2-10 in all populations,with the mean of 5.6.The average expected heterozygosity(HE) was 0.572,indicating a moderate polymorphism.The results of genetic differentiation coefficient(FST) showed that population genetic differentiation was significant between Changbai and Lesser Khingan Mountains(p〈0.001).This result was verified further by Nei's genetic distance(DA) based on UPGMA phy-logenetic trees and by AMOVA analysis.In conclusion,the populations distributed in Lesser Khingan Mountains and Changbai Mountain are proposed to be two distinct management units(MUs) for their protection and management. 展开更多
关键词 Dybowski's frog(Rana dybowskii) genetic diversity genetic differentiation management units(MUs) MICROSATELLITE
在线阅读 下载PDF
IL-36β Promotes Inflammatory Activity and Inhibits Differentiation of Keratinocytes In Vitro 被引量:1
9
作者 王文明 吴超 +1 位作者 余晓玲 晋红中 《Chinese Medical Sciences Journal》 CAS CSCD 2019年第3期199-204,共6页
Objective Psoriasis is an immune-mediated inflammatory disease.Despite advances in the study of its pathogenesis,the exact development mechanism of psoriasis remains to be fully elucidated.Hyperproliferative epidermis... Objective Psoriasis is an immune-mediated inflammatory disease.Despite advances in the study of its pathogenesis,the exact development mechanism of psoriasis remains to be fully elucidated.Hyperproliferative epidermis plays a crucial role in psoriasis.This study aimed to investigate the effects of interleukin-36β(IL-36β)on keratinocyte dysfunction in vitro.Methods Human keratinocyte cell lines,HaCaT cells,were treated with 0(control),50 or 100 ng/ml IL-36βrespectively for 24 h.Cell viability was determined with a cell counting kit-8 assay.Flow cytometry was used to assess the effects of IL-36βon apoptosis and cell cycle distribution.Expressions of the differentiation markers,such as keratin 10 and involucrin,were evaluated by quantitative real-time polymerase chain reaction(RT-qPCR).Expressions of the inflammatory cytokines,IL-1βand IL-6 were tested by ELISA.Results CCK8 assay showed the survival rate had no significant difference between the control and treated group(P>0.05).Flow cytometry analysis showed cell cycle arrest at S phase in the IL-36β-treated groups compared with the control group(P<0.05).RT-qPCR verified the decreased mRNA expressions of keratin 10 and involucrin in the IL-36β-treated groups compared with the negative control(P<0.01).ELISA showed 100 ng/ml IL-36βenhanced levels of IL-1βand IL-6 in culture supernatants of HaCaT cells compared with the negative control(P<0.05).Conclusion Taken together,these findings suggest that IL-36βcould induce cell cycle arrest at S phase,inhibit keratin 10 and involucrin expressions and promote inflammatory activity in HaCaT cell lines. 展开更多
关键词 interleukin-36β PSORIASIS KERATINOCYTES INFLAMMATORY activity differentiation
在线阅读 下载PDF
Genetic Correction and Hepatic Differentiation of Hemophilia B-specific Human Induced Pluripotent Stem Cells 被引量:2
10
作者 何琼 王惠荟 +4 位作者 程涛 袁卫平 马钰波 蒋永平 任志华 《Chinese Medical Sciences Journal》 CAS CSCD 2017年第3期135-144,共10页
Objective To genetically correct a disease-causing point mutation in human induced pluripotent stem cells (iPSCs) derived from a hemophilia B patient. Methods First, the disease-causing mutation was detected by ... Objective To genetically correct a disease-causing point mutation in human induced pluripotent stem cells (iPSCs) derived from a hemophilia B patient. Methods First, the disease-causing mutation was detected by sequencing the encoding area of human coagulation factor IX (F IX) gene. Genomic DNA was extracted from the iPSCs, and the primers were designed to amplify the eight exons of F IX. Next, the point mutation in those iPSCs was genetically corrected using CRISPR/Cas9 technology in the presence of a 129-nucleotide homologous repair template that contained two synonymous mutations. Then, top 8 potential off-target sites were subsequently analyzed using Sanger sequencing. Finally, the corrected clones were differentiated into hepatocyte-like cells, and the secretion of F IX was validated by immunocytochemistry and ELISA assay.Results The cell line bore a missense mutation in the 6th coding exon (c.676 C〉T) of F IX gene. Correction of the point mutation was achieved via CRISPR/Cas9 technology in situ with a high efficacy at about 22% (10/45) and no off-target effects detected in the corrected iPSC clones. F IX secretion, which was further visualized by immunocytochemistry and quantified by ELISA in vitro, reached about 6 ng/ml on day 21 of differentiation procedure. Conclusions Mutations in human disease-specific iPSCs could be precisely corrected by CRISPR/Cas9 technology, and corrected cells still maintained hepatic differentiation capability. Our findings might throw a light on iPSC-based personalized therapies in the clinical application, especially for hemophilia B. 展开更多
关键词 hemophilia B human induced pluripotent stem cells CRISPR/Cas9 genetic correction hepatic differentiation
在线阅读 下载PDF
Analysis of genetic diversity and differentiation of artificial populations of yellowhorn(Xanthoceras sorbifolium) in China using ISSR markers 被引量:4
11
作者 Chanhoon An Hyunseok Lee +3 位作者 Jeonghoon Lee Eun Ju Cheong Yuhua Li Jae-Seon Yi 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第5期1099-1104,共6页
Yellowhorn (Xanthoceras sorbifolium Bunge) is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple se... Yellowhorn (Xanthoceras sorbifolium Bunge) is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple sequence repeat (ISSR) analysis showed genetic variation among four artificial populations in China: two in Inner Mongolia (IM), one in Liaoning (LN), and one in Shandong (SD). The average percentage of polymorphic loci was 81.25 % for these four populations. The Forest Farm in SD showed the highest number of effective alleles (Ne), Shannon index (I), and expected heterozygosity (He), i.e., 1.598, 0.470, and 0.325, respectively, but the lowest number of alleles (Na) as 1.600. Based on an analysis of molecular variance, 23 % of the total genetic variation was found among populations, and 77 % within populations. A principal coordinate analysis revealed two groups (Group 1: Lindonglinchang, Jianping Agriculture Research Station and Forest Farm; Group 2: Jinjilinchang). Understanding the genetic diversity among artificial yellowhorn populations in China, detected using ISSRs, will be useful for yellowhorn conservation and improvement. Additional arti-ficial and natural populations need to be included in the future for a country-wide perspective. 展开更多
关键词 differentiation - Diversity ISSR POPULATIONSTRUCTURE Xanthoceras sorbifolium Yellowhorn
在线阅读 下载PDF
Cardiomyocyte-like differentiation of human bone marrow mesenchymal stem cells after exposure to 5-azacytidine in vitro 被引量:5
12
作者 Feng CAO Lili NIU Ling MENG Lianxu ZHAO Dongmei Wang Ming ZHENG Cixian BAI Guoliang JIA Xuetao PEI 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2004年第2期101-107,共7页
Objective To investigate the potential of adult mesenchymal stem cells (MSCs) derived from human bone marrow to undergo cardiomyogenic differentiation after exposure to 5-azacytidine (5-aza) in vitro. Methods A small ... Objective To investigate the potential of adult mesenchymal stem cells (MSCs) derived from human bone marrow to undergo cardiomyogenic differentiation after exposure to 5-azacytidine (5-aza) in vitro. Methods A small bone marrow aspirate was taken from the iliac crest of human volunteers, and hMSCs were isolated by 1.073g/mL Percoll and propagated in the right cell culturing medium as previously described. The phenotypes of hMSCs were characterized with the use of flow cytometry. The hMSCs were cultured in cell culture medium (as control) and medium mixed with 5-aza for cellular differentiation. We examined by immunohistochemistry at 21 days the inducement of desmin, cardiac-specific cardiac troponin I (cTnI), GATA 4 and connexin-43 respectively. Results The hMSCs are fibroblast-like morphology and express CD44+ CD29+ CD90+ / CD34- CD45- CD31- CD11a. After 5-aza treatment, 20-30% hMSCs connected with adjoining cells and coalesced into myotube structures after 14days. Twenty-one days after 5-aza treatment, immunofluorescence showed that some cells expressed desmin,GATA4, cTnI and connexin-43 in 5,10 μmol/L 5-aza groups, but no cardiac specific protein was found in neither 3μmol/L 5-aza group nor in the control group. The ratio of cTnI positively stained cells in 10 μmol/L group was higher than that in 5 μmol/L group (65.3 ± 4.7% vs 48.2 ± 5.4%, P < 0.05). Electron microscopy revealed that myofilaments were formed. The induced cells expressed cardiac-myosin heavy chain (MyHC) gene by reverse transcription-polymerase chain reaction (RT-PCR). Conclusions Theses findings suggest that hMSCs from adult bone marrow can be differentiated into cardiac-like muscle cells with 5-aza inducement in vitro and the differentiation is in line with the 5-aza concentration. (J Geriatr Cardiol 2004;1(2) :101-107. ) 展开更多
关键词 human bone MARROW MESENCHYMAL stem cells CARDIOMYOCYTES differentiation 5-AZACYTIDINE
在线阅读 下载PDF
EEG Source Localization Using Spatio-Temporal Neural Network 被引量:4
13
作者 Song Cui Lijuan Duan +4 位作者 Bei Gong Yuanhua Qiao Fan Xu Juncheng Chen Changming Wang 《China Communications》 SCIE CSCD 2019年第7期131-143,共13页
Source localization of focal electrical activity from scalp electroencephalogram (sEEG) signal is generally modeled as an inverse problem that is highly ill-posed. In this paper, a novel source localization method is ... Source localization of focal electrical activity from scalp electroencephalogram (sEEG) signal is generally modeled as an inverse problem that is highly ill-posed. In this paper, a novel source localization method is proposed to model the EEG inverse problem using spatio-temporal long-short term memory recurrent neural networks (LSTM). The network model consists of two parts, sEEG encoding and source decoding, to model the sEEG signal and receive the regression of source location. As there does not exist enough annotated sEEG signals correspond to specific source locations, simulated data is generated with forward model using finite element method (FEM) to act as a part of training signals. A framework for source localization is proposed to estimate the source position based on simulated training data. Experiments are done on simulated testing data. The results on simulated data exhibit good robustness on noise signal, and the proposed network solves the EEG inverse problem with spatio-temporal deep network. The result show that the proposed method overcomes the highly ill-posed linear inverse problem with data driven learning. 展开更多
关键词 ELECTROENCEPHALOGRAM LSTM SOURCE LOCALIZATION spatio-temporal MODELING
在线阅读 下载PDF
Dynamic Expression Profiles of Marker Genes in Osteogenic Differentiation of Human Bone Marrow-derived Mesenchymal Stem Cells 被引量:2
14
作者 Liang Wang Zheng-yao Li +2 位作者 Yi-peng Wang Zhi-hong Wu Bin Yu 《Chinese Medical Sciences Journal》 CAS CSCD 2015年第2期108-113,共6页
Objective To observe the expression profiles of osteoblast-related genes in human mesenchymal stem cells(MSCs) derived from bone marrow during osteogenic differentiation. Methods MSCs were induced to differentiate wit... Objective To observe the expression profiles of osteoblast-related genes in human mesenchymal stem cells(MSCs) derived from bone marrow during osteogenic differentiation. Methods MSCs were induced to differentiate with MSC osteogenic differentiation medium for 7, 14, 21 and 28 days respectively. Alizarin Red staining was used to detect matrix mineralization. Expression of osteoblast-related genes, including osteocalcin, osteopontin, Runt-related transcription factor 2(Runx2), alkaline phosphatase and collagen type Ⅰ, was assessed with quantitative reverse transcription-polymerase chain reaction. Results On day 14 after induction of differentiation, cells were stained positively with Alizarin Red. The expression levels of these genes exhibited an upward trend as induction time was prolonged. Exposure to osteogenic differentiation medium less than 21 days did not significantly induce osteocalcin expression; osteocalcin expression levels in the differentiated cells induced for 21 and 28 days were 1.63 and 2.46 times as high as the undifferentiated cells respectively(all P<0.05). Stimulation with MSC osteogenic differentiation medium over 14 days significantly enhanced bone marrow-derived MSCs to express osteopontin and Runx2 genes(all P<0.05). Osteogenic differentiation medium could significantly induce the expressions of alkaline phosphatase and collagen type Ⅰgenes(all P<0.05). Their expressions reached the peak levels on day 21, which were increased more than 4- and 3-fold respectively. Conclusion Human bone marrow-derived MSCs could exhibit the sequential expression pattern of osteoblast marker genes during osteogenic differentiation in vitro. 展开更多
关键词 MESENCHYMAL STEM cell GENE expression OSTEOGENESIS OSTEOBLAST differentiation
在线阅读 下载PDF
Genetic diversity and genetic differentiation of natural Pinus koraiensis population 被引量:10
15
作者 FENG Fu-juan HAN Shi-jie WANG Hong-mei 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期21-24,共4页
Genetic diversities and genetic differentiations of the four Pinus koraiensis populations (Gaofeng Forestry Farm at Tangwanghe in Yichun City, Erdaobaihe Town in the Changbai Mountains, Shcngshan Forestry Farm in Hei... Genetic diversities and genetic differentiations of the four Pinus koraiensis populations (Gaofeng Forestry Farm at Tangwanghe in Yichun City, Erdaobaihe Town in the Changbai Mountains, Shcngshan Forestry Farm in Heihe City, in China, and the suburb of Vladivostok City in Russia) were analyzed by using ISSR PCR technique. The results of 15 primers amplification showed that the ratio of polymorphic site of P koralensis population was 60.7%. Euch primer had 3.6 polymorphic sites, The diversity levels of the four P. koraiensis populations were rather higher compared with those of other Pinaceae species. The genetic diversity levels of t: koraiensis populations grown in the center region were higher than those grown in the edge zone. The genetic diversity of r3 koraiensis mainly came from the interiot of the population, accounting for 73% of total genetic diversity. There were no positive correlation between genetic distances and geographical distances for the four P koraiensis populations. The gradual decrease of natural distribution region of P. koraiensis was due to anthropic destroy and environmental factors (i.e. fire and wind throw), rather than the lower genetic diversity. 展开更多
关键词 Genetic differentiation Genetic diversity ISSR Pinus koraiensis
在线阅读 下载PDF
ESSENTIAL NORMS OF PRODUCTS OF WEIGHTED COMPOSITION OPERATORS AND DIFFERENTIATION OPERATORS BETWEEN BANACH SPACES OF ANALYTIC FUNCTIONS 被引量:4
16
作者 Jasbir Singh MANHAS Ruhan ZHAO 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1401-1410,共10页
We obtain several estimates of the essential norms of the products of differen- tiation operators and weighted composition operators between weighted Banach spaces of analytic functions with general weights. As applic... We obtain several estimates of the essential norms of the products of differen- tiation operators and weighted composition operators between weighted Banach spaces of analytic functions with general weights. As applications, we also give estimates of the es- sential norms of weighted composition operators between weighted Banach space of analytic functions and Bloch-type spaces. 展开更多
关键词 differentiation operators weighted composition operators weighted Banachspace of analytic functions Bloch-type spaces essential norms
在线阅读 下载PDF
Nanostructured Graphene Surfaces Promote Different Stages of Bone Cell Differentiation 被引量:2
17
作者 F.F.Borghi P.A.Bean +3 位作者 M.D.M.Evans T.van der Laan S.Kumar K.Ostrikov 《Nano-Micro Letters》 SCIE EI CAS 2018年第3期103-114,共12页
Nanostructured graphene films were used as platforms for the differentiation of Saos-2 cells into bonelike cells. The films were grown using the plasma-enhanced chemical vapor deposition method, which allowed the prod... Nanostructured graphene films were used as platforms for the differentiation of Saos-2 cells into bonelike cells. The films were grown using the plasma-enhanced chemical vapor deposition method, which allowed the production of both vertically and horizontally aligned carbon nanowalls(CNWs). Modifications of the techniqueallowed control of the density of the CNWs and their orientation after the transfer process. The influence of two different topographies on cell attachment, proliferation,and differentiation was investigated. First, the transferred graphene surfaces were shown to be noncytotoxic and were able to support cell adhesion and growth for over 7 days.Second, early cell differentiation(identified by cellular alkaline phosphatase release) was found to be enhanced on the horizontally aligned CNW surfaces, whereas mineralization(identified by cellular calcium production), a later stage of bone cell differentiation, was stimulated by the presence of the vertical CNWs on the surfaces. These results show that the graphene coatings, grown using the presented method, are biocompatible. And their topographies have an impact on cell behavior, which can be useful in tissue engineering applications. 展开更多
关键词 Carbon nanowalls Graphene films Bone cell Cell differentiation Plasma nanoscience
在线阅读 下载PDF
Spatio-temporal variation and propagation direction of coal fire in Jharia Coalfield,India by satellite-based multi-temporal night-time land surface temperature imaging 被引量:4
18
作者 Narendra Singh R.S.Chatterjee +1 位作者 Dheeraj Kumar D.C.Panigrahi 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第5期765-778,共14页
In this paper,the spatio-temporal variation and propagation direction of coal fire were studied in the Jharia Coalfield(JCF),India during 2006–2015 through satellite-based night-time land surface temperature(LST)imag... In this paper,the spatio-temporal variation and propagation direction of coal fire were studied in the Jharia Coalfield(JCF),India during 2006–2015 through satellite-based night-time land surface temperature(LST)imaging.The LST was retrieved from Advanced Spaceborne Thermal Emission and Reflection Radiometer(ASTER)night-time thermal-infrared data by a robust split-window algorithm based on scene-specific regression coefficients,band-specific hybrid emissivity,and night-time atmospheric transmittance.The LST-profile-based coal fire detection algorithm was formulated through statistical analysis of the LST values along multiple transects across diverse coal fire locations in the JCF in order to compute date-specific threshold temperatures for separating thermally-anomalous and background pixels.This algorithm efficiently separates surface fire,subsurface fire,and thermally-anomalous transitional pixels.During the observation period,it was noticed that the coal fire area increased significantly,which resulted from new coal fire at many places owing to extensive opencast-mining operations.It was observed that the fire propagation occurred primarily along the dip direction of the coal seams.At places,lateral-propagation of limited spatial extent was also observed along the strike direction possibly due to spatial continuity of the coal seams along strike.Moreover,the opencast-mining activities carried out during 2009–2015 and the structurally weak planes facilitated the fire propagation. 展开更多
关键词 Satellite-based night-time imaging Land surface temperature Coal fire spatio-temporal variation Propagation direction Jharia Coalfield
在线阅读 下载PDF
GRADIENT ESTIMATES FOR THE COMMUTATOR WITH FRACTIONAL DIFFERENTIATION FOR SECOND ORDER ELLIPTIC OPERATORS 被引量:1
19
作者 Wenyu TAO bnping CHEN Jili LI 《Acta Mathematica Scientia》 SCIE CSCD 2019年第5期1255-1264,共10页
Let L=-div(A▽) be a second order divergence form elliptic operator, where A is an accretive, n×n matrix with bounded measurable complex coefficients on R^n. Let L^α/2 (0 <α< 1) denotes the fractional dif... Let L=-div(A▽) be a second order divergence form elliptic operator, where A is an accretive, n×n matrix with bounded measurable complex coefficients on R^n. Let L^α/2 (0 <α< 1) denotes the fractional differential operator associated with L and (-△)^α/2b ∈ L^n/α(R^n). In this article, we prove that the commutator[b, L^α/2] is bounded from the homogenous Sobolev space Lα%2 (R^n) to L^2(R^n). 展开更多
关键词 COMMUTATOR FRACTIONAL differentiation ELLIPTIC OPERATORS SOBOLEV space
在线阅读 下载PDF
Correlation between growth differentiation factor-15 and collagen metabolism indicators in patients with myocardial infarction and heart failure 被引量:15
20
作者 Fang-Fang WANG Bao-Xia CHEN +3 位作者 Hai-Yi YU Lin MI Zi-Jian LI Wei GAO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第1期88-93,共6页
BackgroundGrowth differentiation factor (GDF)-15, a divergent member of the transforming growth factor beta super-family does appear to be up-regulated in response to experimental pressure overload and progression o... BackgroundGrowth differentiation factor (GDF)-15, a divergent member of the transforming growth factor beta super-family does appear to be up-regulated in response to experimental pressure overload and progression of heart failure (HF). HF frequently develops after myocardial infarction (MI), contributing to worse outcome. The aim of this study is to assess the correlation between GDF-15 levels and markers related to collagen turnover in different stages of HF.MethodsThe study consists of a cohort of 179 patients, including stable angina pectoris patients (AP group,n= 50), old MI patients without HF (OMI group,n = 56), old MI patients with HF (OMI-HF group,n= 38) and normal Control group (n = 35). Both indicators reflecting the synthesis and degradation rates of collagen including precollagen I N-terminal peptide (PINP), type I collagen carboxy-terminal peptide (ICTP), precollagen III N-terminal peptide (PIIINP) and GDF-15 were measured using an enzyme-linked inmunosorbent assay.ResultsThe plasma GDF-15 level was higher in OMI-HF group (1373.4 ± 275.4 ng/L) than OMI group (1036.1 ± 248.6 ng/L), AP group (784.6 ± 222.4 ng/L) and Control group (483.8 ± 186.4 ng/L) (P〈 0.001). The indi-cators of collagen turnover (ICTP, PINP, PIIINP) all increased in the OMI-HF group compared with Control group (3.03 ± 1.02μg/Lvs. 2.08 ± 0.95μg/L, 22.2 ± 6.6μg/Lvs. 16.7 ± 5.1μg/L and 13.2 ± 7.9μg/Lvs. 6.4 ± 2.1μg/L, respectively;P〈 0.01). GDF-15 positively cor-related with ICTP and PIIINP (r = 0.302,P〈 0.001 andr= 0.206,P= 0.006, respectively). GDF-15 positively correlated to the echocardio-graphic diastolic indicators E/Em and left atrial pressure (r= 0.349 and r= 0.358, respectively;P〈 0.01), and inversely correlated to the systolic indicators left ventricular ejection fraction and the average of peak systolic myocardial velocities (Sm) (r=-0.623 and r=-0.365, respectively;P〈 0.01).ConclusionPlasma GDF-15 is associated with the indicators of type I and III collagen turnover. 展开更多
关键词 Biomarkers Collagen turnover Growth differentiation factor- 15 Heart failure Myocardial infarction
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部