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Identification and Validation of SLC9A2 as A Potential Tumor Suppressor in Colorectal Cancer:Integrating Bioinformatics Analysis with Experimental Confirmation
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作者 Yan-min LIU Tie-cheng YANG +9 位作者 Xiao-chang FANG Li-jie YANG Li-wen SHI Hua-qiao WANG Ting-ting DOU Lin SHU Tian-Liang CHEN Jun HU Xiao-ming YU Xuan-fei LI 《Current Medical Science》 SCIE CAS 2024年第3期529-544,共16页
Objective To uncover the mechanisms underlying the development of colorectal cancer(CRC),we applied bioinformatic analyses to identify key genes and experimentally validated their possible roles in CRC onset and progr... Objective To uncover the mechanisms underlying the development of colorectal cancer(CRC),we applied bioinformatic analyses to identify key genes and experimentally validated their possible roles in CRC onset and progression.Methods We performed Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis on differentially expressed genes(DEGs),constructed a protein-protein interaction(PPI)network to find the top 10 hub genes,and analyzed their expression in colon adenocarcinoma(COAD)and rectum adenocarcinoma(READ).We also studied the correlation between these genes and immune cell infiltration and prognosis and validated the expression of SLC9A2 in CRC tissues and cell lines using qRT-PCR and Western blotting.Functional experiments were conducted in vitro to investigate the effects of SLC9A2 on tumor growth and metastasis.Results We found 130 DEGs,with 45 up-regulated and 85 down-regulated in CRC.GO analysis indicated that these DEGs were primarily enriched in functions related to the regulation of cellular pH,zymogen granules,and transmembrane transporter activity.KEGG pathway analysis revealed that the DEGs played pivotal roles in pancreatic secretion,rheumatoid arthritis,and the IL-17 signaling pathway.We identified 10 hub genes:CXCL1,SLC26A3,CXCL2,MMP7,MMP1,SLC9A2,SLC4A4,CLCA1,CLCA4,and ZG16.GO enrichment analysis showed that these hub genes were predominantly involved in the positive regulation of transcription.Gene expression analysis revealed that CXCL1,CXCL2,MMP1,and MMP7 were highly expressed in CRC,whereas CLCA1,CLCA4,SLC4A4,SLC9A2,SLC26A3,and ZG16 were expressed at lower levels.Survival analysis revealed that 5 key genes were significantly associated with the prognosis of CRC.Both mRNA and protein expression levels of SLC9A2 were markedly reduced in CRC tissues and cell lines.Importantly,SLC9A2 overexpression in SW480 cells led to a notable inhibition of cell proliferation,migration,and invasion.Western blotting analysis revealed that the expression levels of phosphorylated ERK(p-ERK)and phosphorylated JNK(p-JNK)proteins were significantly increased,whereas there were no significant changes in the expression levels of ERK and JNK following SLC9A2 overexpression.Correlation analysis indicated a potential link between SLC9A2 expression and the MAPK signaling pathway.Conclusion Our study suggests that SLC9A2 acts as a tumor suppressor through the MAPK pathway and could be a potential target for CRC diagnosis and therapy. 展开更多
关键词 SLC9A2 colorectal cancer bioinformatic analysis biomarkers immune infiltrate
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Transglutaminase 2 serves as a pathogenic hub gene of KRAS mutant colon cancer based on integrated analysis
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作者 Wei-Bin Peng Yu-Ping Li +1 位作者 Yong Zeng Kai Chen 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期2074-2090,共17页
BACKGROUND Colon cancer is acknowledged as one of the most common malignancies worldwide,ranking third in United States regarding incidence and mortality.Notably,approximately 40%of colon cancer cases harbor oncogenic... BACKGROUND Colon cancer is acknowledged as one of the most common malignancies worldwide,ranking third in United States regarding incidence and mortality.Notably,approximately 40%of colon cancer cases harbor oncogenic KRAS mutations,resulting in the continuous activation of epidermal growth factor receptor signaling.AIM To investigate the key pathogenic genes in KRAS mutant colon cancer holds considerable importance.METHODS Weighted gene co-expression network analysis,in combination with additional bioinformatics analysis,were conducted to screen the key factors driving the progression of KRAS mutant colon cancer.Meanwhile,various in vitro experiments were also conducted to explore the biological function of transglutaminase 2(TGM2).RESULTS Integrated analysis demonstrated that TGM2 acted as an independent prognostic factor for progression-free survival.Immunohistochemical analysis on tissue microarrays revealed that TGM2 was associated with an elevated probability of perineural invasion in patients with KRAS mutant colon cancer.Additionally,biological roles of the key gene TGM2 was also assessed,suggesting that the downregulation of TGM2 attenuated the proliferation,invasion,and migration of the KRAS mutant colon cancer cell line.CONCLUSION This study underscores the potential significance of TGM2 in the progression of KRAS mutant colon cancer.This insight not only offers a theoretical foundation for therapeutic approaches but also highlights the need for additional clinical trials and fundamental research to support our preliminary findings. 展开更多
关键词 Colon cancer KRAS mutation Transglutaminase 2 Weighted gene co-expression network analysis
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Multi-Elemental Analysis and 2D Image Mapping within Roots, Leaves and Seeds from O. glaberrima Rice Plants Using Micro-PIXE Technique
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作者 Alassane Traore Anna Ndiaye +6 位作者 Christopher Bongani Mtshali Manneh Baboucarr Jean Paul Latyr Faye Daouda Mbodj Kandiaba Traore Tapha Gueye Ababacar Sadikhe Ndao 《World Journal of Nuclear Science and Technology》 CAS 2024年第2期97-106,共10页
Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micr... Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micro-analytical imaging techniques are required to reveal its accumulation and distribution within plant tissues. PIXE studies have been performed to determine different elements in rice plants. The existing microbeam analytical technique at the iThemba LABS will be applied for the 2D image mapping of fresh rice tissues to perform a concentration of low atomic mass elements (such as Al, Si, P, S, Cl, Ca, Ti, Mn, Fe, Cu, Br, Zn and K) with detection limits of typically 1-10 μg/g. Comparison of the distribution of the elements between leaves, root and seed samples using uptake and distribution of elements in particular environmental conditions with potential amount of salt in water have been performed. We are also expecting to indicate metal exclusion as salt tolerance strategies from leaves, root, and seed compartments using matrix correlation between samples and between elements on rice species. 展开更多
关键词 PIXE 2D Mapping Rice Concentration Elemental analysis
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Prognostic significance of CDKN2A expression in colon adenocarcinoma: insights from TCGA analysis
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作者 Wei Fu Yao Wang +3 位作者 Qin-Ming Yan Guo-Bin Cheng Lin-Ya Lyu Yao Ding 《Cancer Advances》 2024年第16期1-10,共10页
Background:The cyclin-dependent kinase inhibitor 2a(CDKN2A)gene,identified as the multiple tumor suppressor gene,functions as a regulatory gene implicated in cancer pathogenesis.Its significance lies in its pivotal in... Background:The cyclin-dependent kinase inhibitor 2a(CDKN2A)gene,identified as the multiple tumor suppressor gene,functions as a regulatory gene implicated in cancer pathogenesis.Its significance lies in its pivotal involvement in the genesis of various tumors;notwithstanding,the precise connection between CDKN2A and c olon adenocarcinoma(COAD)remains undisclosed.Methods:The objective of this research was to assess the predictive importance of CDKN2A in COAD by analyzing data from The Cancer Genome Atlas database.Logistic regression,signed rank test,Wilcoxon test,and Kruskal-Wallis test were used to examine CDKN2A expression levels and clinicopathological features.Univariate and multivariate Cox r egression analyses and Kaplan-Meier analysis found prognostic variables.Additionally,gene set enrichment analysis identified key CDKN2A expression pathways.The study additionally examined CDKN2A expression with tumor immune infiltration using The Cancer Genome Atlas data and single sample gene set enrichment analysis.Results:The results of this investigation indicated a substantial connection between higher CDKN2A expression and negative outcomes in terms of overall survival and disease-related survival among COAD patients.Gene set enrichment analysis indicated a tight link between CDKN2A and both the cell cycle and hedgehog signaling pathways.Subsequent evaluation employing single sample gene set enrichment analysis demonstrated a positive link between CDKN2A expression with infiltration by iDCs,whereas a negative correlation was detected with infiltration by helper T cells.Conclusion:In conclusion,the present study gives strong data supporting the predictive value of CDKN2A and its possible usefulness as a biomarker for COAD.Additionally,our results show a reasonable link between CDKN2A expression and immune influx in COAD,putting light on the role of CDKN2A in the control of the tumor microenvironment.Nevertheless,additional studies are needed to confirm the underlying mechanisms of these relationships and to discover the therapeutic possibilities of targeting CDKN2A in the treatment of COAD. 展开更多
关键词 CDKN2A colon adenocarcinoma immune infiltration prognostic analysis helper T cells
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Numerical Analysis of Steady Smoldering of Biomass Rods
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作者 Zhao Wentao Yu Guangxin +3 位作者 Zhang Yi Wang Youtang Zhou Dan He Fang 《燃烧科学与技术》 CAS CSCD 北大核心 2024年第5期507-519,共13页
Understanding the steady mechanism of biomass smoldering plays a great role in the utilization of smoldering technology.In this study numerical analysis of steady smoldering of biomass rods was performed.A two-dimensi... Understanding the steady mechanism of biomass smoldering plays a great role in the utilization of smoldering technology.In this study numerical analysis of steady smoldering of biomass rods was performed.A two-dimensional(2D)steady model taking into account both char oxidation and pyrolysis was developed on the basis of a calculated propagation velocity according to empirical correlation.The model was validated against the smoldering experiment of biomass rods under natural conditions,and the maximum error was smaller than 31%.Parameter sensitivity analysis found that propagation velocity decreases significantly while oxidation area and pyrolysis zone increase significantly with the increasing diameter of rod fuel. 展开更多
关键词 steady smoldering biomass rod numerical analysis 2D steady model sensitivity analysis
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Sentiment Analysis Using E-Commerce Review Keyword-Generated Image with a Hybrid Machine Learning-Based Model
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作者 Jiawen Li Yuesheng Huang +3 位作者 Yayi Lu Leijun Wang Yongqi Ren Rongjun Chen 《Computers, Materials & Continua》 SCIE EI 2024年第7期1581-1599,共19页
In the context of the accelerated pace of daily life and the development of e-commerce,online shopping is a mainstreamway for consumers to access products and services.To understand their emotional expressions in faci... In the context of the accelerated pace of daily life and the development of e-commerce,online shopping is a mainstreamway for consumers to access products and services.To understand their emotional expressions in facing different shopping experience scenarios,this paper presents a sentiment analysis method that combines the ecommerce reviewkeyword-generated imagewith a hybrid machine learning-basedmodel,inwhich theWord2Vec-TextRank is used to extract keywords that act as the inputs for generating the related images by generative Artificial Intelligence(AI).Subsequently,a hybrid Convolutional Neural Network and Support Vector Machine(CNNSVM)model is applied for sentiment classification of those keyword-generated images.For method validation,the data randomly comprised of 5000 reviews from Amazon have been analyzed.With superior keyword extraction capability,the proposedmethod achieves impressive results on sentiment classification with a remarkable accuracy of up to 97.13%.Such performance demonstrates its advantages by using the text-to-image approach,providing a unique perspective for sentiment analysis in the e-commerce review data compared to the existing works.Thus,the proposed method enhances the reliability and insights of customer feedback surveys,which would also establish a novel direction in similar cases,such as social media monitoring and market trend research. 展开更多
关键词 Sentiment analysis keyword-generated image machine learning Word2Vec-TextRank CNN-SVM
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Data driven analysis reveals prognostic genes and immunological targets in human sepsis-associated acute kidney injury
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作者 Qing Zhao Jinfu Ma +2 位作者 Jianguo Xiao Zhe Feng Hui Liu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第2期91-97,共7页
BACKGROUND:The molecular mechanism of sepsis-associated acute kidney injury(SA-AKI)is unclear.We analyzed co-differentially expressed genes(co-DEGs)to elucidate the underlying mechanism and intervention targets of SA-... BACKGROUND:The molecular mechanism of sepsis-associated acute kidney injury(SA-AKI)is unclear.We analyzed co-differentially expressed genes(co-DEGs)to elucidate the underlying mechanism and intervention targets of SA-AKI.METHODS:The microarray datasets GSE65682,GSE30718,and GSE174220 were downloaded from the Gene Expression Omnibus(GEO)database.We identified the co-DEGs and constructed a gene co-expression network to screen the hub genes.We analyzed immune correlations and disease correlations and performed functional annotation of the hub genes.We also performed single-cell and microenvironment analyses and investigated the enrichment pathways and the main transcription factors.Finally,we conducted a correlation analysis to evaluate the role of the hub genes.RESULTS:Interleukin 32(IL32)was identified as the hub gene in SA-AKI,and the main enriched signaling pathways were associated with hemopoiesis,cellular response to cytokine stimulus,inflammatory response,and regulation of kidney development.Additionally,IL32 was significantly associated with mortality in SA-AKI patients.Monocytes,macrophages,T cells,and NK cells were closely related to IL32 and were involved in the immune microenvironment in SA-AKI patients.IL32 expression increased significantly in the kidney of septic mouse.Toll-like receptor 2(TLR2)was significantly and negatively correlated with IL32.CONCLUSION:IL32 is the key gene involved in SA-AKI and is significantly associated with prognosis.TLR2 and relevant immune cells are closely related to key genes. 展开更多
关键词 SEPSIS Acute kidney injury Interleukin 32 Toll-like receptor 2 Bioinformatics analysis
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Calculations and Sensitivity Analysis of Chlorine-,NO_(x)-,and Bromine-Depleting Cycles of Stratospheric Ozone
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作者 Ibraheem Alelmi Sen Nieh 《Journal of Environmental Science and Engineering(B)》 CAS 2024年第2期53-69,共17页
This paper presents an engineering system approach using a 2D model of conservation of mass to study the dynamics of ozone and concerned chemical species in the stratosphere.By considering all fourteen photolysis,ozon... This paper presents an engineering system approach using a 2D model of conservation of mass to study the dynamics of ozone and concerned chemical species in the stratosphere.By considering all fourteen photolysis,ozone-generating,and-depleting chemical reactions,the model calculated the transient,spatial changes of ozone under different physical-chemical-radiative conditions.Validation against the measured data demonstrated good accuracy,close match of our model with the observed ozone concentrations at both 20°S and 90°N locations.The deviation in the average concentration was less than 1% and in ozone profiles less than 17%.The impacts of various chlorine-(Cl),nitrogen oxides-(NO_(x)),and bromine-(Br)depleting cycles on ozone concentrations and distribution were investigated.The chlorine catalytic depleting cycle was found to exhibit the most significant impact on ozone dynamics,confirming the key role of chlorine in the problem of ozone depletion.Sensitivity analysis was conducted with levels of 25%,50%,100%,200%,and 400% of the baseline value.The combined cycles(Cl+NO_(x)+Br)showed the most significant influence on ozone behavior.The total ozone abundance above the South Pole could decrease by a small 3%,from 281 DU(Dubson Units)to 273 DU for the 25% level,or by a huge thinning of 60%to 114 DU for the 400% concentration level.When the level of chlorine gases increased beyond 200%,it would cause ozone depletion to a level of ozone hole(below 220 DU).The 2D Ozone Model presented in this paper demonstrates robustness,convenience,efficiency,and executability for analyzing complex ozone phenomena in the stratosphere. 展开更多
关键词 Ozone depletion 2-D model CHLORINE BROMINE nitrogen oxides sensitivity analysis total ozone abundance DU
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Numerical analysis of matrix swelling and its effect on microstructure of digital coal and its associated permeability during CO_(2)-ECBM process based on X-ray CT data 被引量:1
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作者 Hui-Huang Fang Zhang-Fei Wang +1 位作者 Shu-Xun Sang Yan-Hui Huang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期87-101,共15页
Matrix swelling effect will cause the change of microstructure of coal reservoir and its permeability,which is the key factor affecting the engineering effect of CO_(2)-ECBM technology.The Sihe and Yuwu collieries are... Matrix swelling effect will cause the change of microstructure of coal reservoir and its permeability,which is the key factor affecting the engineering effect of CO_(2)-ECBM technology.The Sihe and Yuwu collieries are taken as research objects.Firstly,visualization reconstruction of coal reservoir is realized.Secondly,the evolution of the pore/fracture structures under different swelling contents is discussed.Then,the influence of matrix phase with different swelling contents on permeability is discussed.Finally,the mechanism of swelling effect during the CO_(2)-ECBM process is further discussed.The results show that the intra-matrix pores and matrix-edge fractures are the focus of this study,and the contacting area between matrix and pore/fracture is the core area of matrix swelling.The number of matrix particles decreases with the increase of size,and the distribution of which is isolated with small size and interconnected with large size.The swelling effect of matrix particles with larger size has a great influence on the pore/fracture structures.The number of connected pores/fractures is limited and only interconnected in a certain direction.With the increase of matrix swelling content,the number,porosity,width,fractal dimension,surface area and volume of pores/fractures decrease,and their negative contribution to absolute permeability increases from 0.368% to 0.633% and 0.868%-1.404%,respectively.With the increase of swelling content,the number of intra-matrix pores gradually decreases and the pore radius becomes shorter during the CO_(2)-ECBM process.The matrix continuously expands to the connected fractures,and the width of connected fractures gradually shorten.Under the influence of matrix swelling,the bending degree of fluid flow increases gradually,so the resistance of fluid migration increases and the permeability gradually decreases.This study shows that the matrix swelling effect is the key factor affecting CBM recovery,and the application of this effect in CO_(2)-ECBM process can be discussed. 展开更多
关键词 Matrix swelling CO_(2)-ECBM Absolutely permeability Numerical analysis X-ray CT Qinshui Basin
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Dynamic Modeling and Sensitivity Analysis for an MEA-Based CO_(2) Capture Absorber
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作者 Hongwei Guan Lingjian Ye +2 位作者 Yurun Wang Feifan Shen Yuchen He 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3535-3550,共16页
The absorber is the key unit in the post-combustion monoethanolamine(MEA)-based carbon dioxide(CO_(2))capture process.A rate-based dynamic model for the absorber is developed and validated using steady-state experimen... The absorber is the key unit in the post-combustion monoethanolamine(MEA)-based carbon dioxide(CO_(2))capture process.A rate-based dynamic model for the absorber is developed and validated using steady-state experimental data reported in open literature.Sensitivity analysis is performed with respect to important model parameters associated with the reaction,mass transport and phy-sical property relationships.Then,a singular value decomposition(SVD)-based subspace parameter estimation method is proposed to improve the model accu-racy.Finally,dynamic simulations are carried out to investigate the effects of the feed rate of lean MEA solution and the flue inlet conditions.Simulation results indicate that the established dynamic model can reasonably reflect the physical behavior of the absorber.Some new insights are gained from the simulation results. 展开更多
关键词 CO_(2)capture dynamic modeling sensitivity analysis model validation
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Multi-scale Incremental Analysis Update Scheme and Its Application to Typhoon Mangkhut(2018)Prediction
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作者 Yan GAO Jiali FENG +4 位作者 Xin XIA Jian SUN Yulong MA Dongmei CHEN Qilin WAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期95-109,共15页
In the traditional incremental analysis update(IAU)process,all analysis increments are treated as constant forcing in a model’s prognostic equations over a certain time window.This approach effectively reduces high-f... In the traditional incremental analysis update(IAU)process,all analysis increments are treated as constant forcing in a model’s prognostic equations over a certain time window.This approach effectively reduces high-frequency oscillations introduced by data assimilation.However,as different scales of increments have unique evolutionary speeds and life histories in a numerical model,the traditional IAU scheme cannot fully meet the requirements of short-term forecasting for the damping of high-frequency noise and may even cause systematic drifts.Therefore,a multi-scale IAU scheme is proposed in this paper.Analysis increments were divided into different scale parts using a spatial filtering technique.For each scale increment,the optimal relaxation time in the IAU scheme was determined by the skill of the forecasting results.Finally,different scales of analysis increments were added to the model integration during their optimal relaxation time.The multi-scale IAU scheme can effectively reduce the noise and further improve the balance between large-scale and small-scale increments in the model initialization stage.To evaluate its performance,several numerical experiments were conducted to simulate the path and intensity of Typhoon Mangkhut(2018)and showed that:(1)the multi-scale IAU scheme had an obvious effect on noise control at the initial stage of data assimilation;(2)the optimal relaxation time for large-scale and small-scale increments was estimated as 6 h and 3 h,respectively;(3)the forecast performance of the multi-scale IAU scheme in the prediction of Typhoon Mangkhut(2018)was better than that of the traditional IAU scheme.The results demonstrate the superiority of the multi-scale IAU scheme. 展开更多
关键词 multi-scale incremental analysis updates optimal relaxation time 2-D discrete cosine transform GRAPES_MESO Typhoon Mangkhut(2018)
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Investigation and Countermeasures of the Development of Chinese Pharmaceutical E-commerce in the B2C Model Based on PEST-SWOT Analysis
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作者 Xiu Yu Wang Shuling 《Asian Journal of Social Pharmacy》 2023年第4期398-405,共8页
Objective To analyze the problems of pharmaceutical e-commerce and provide strategies for its development in the future B2C mode since drug network management has great potential in China.Methods By collecting,identif... Objective To analyze the problems of pharmaceutical e-commerce and provide strategies for its development in the future B2C mode since drug network management has great potential in China.Methods By collecting,identifying,and conducting literature research,PEST-SWOT identification and positioning of pharmaceutical e-commerce in the B2C mode were carried out.Results and Conclusion A PEST-SWOT analysis matrix was established to analyze the status of B2C pharmaceutical e-commerce,and to summarize its advantages,disadvantages,opportunities and threats from four perspectives of politics,economy,society and technology.Suggestions on cultivating compound talents proficient in medicine and e-commerce,exploring online payment methods for medical insurance,integration of upstream and downstream of the industrial chain and data sharing are put forward to promote the healthy and long-term development of pharmaceutical e-commerce under the background of big data. 展开更多
关键词 pharmaceutical e-commerce B2C PEST-SWOT analysis matrix
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Non-isothermal kinetic analysis of thermal dehydration of La_2(CO_3)_3·3.4H_2O in air 被引量:3
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作者 张湘辉 何川 +3 位作者 汪灵 刘菁 邓苗 冯谦 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3378-3385,共8页
The single phase La2(CO3)3·3.4H2 O was synthesized by hydrothermal method. The thermal decomposition and intermediates and final solid products of La2(CO3)3·3.4H2O from 30 to 1000 °C were characteri... The single phase La2(CO3)3·3.4H2 O was synthesized by hydrothermal method. The thermal decomposition and intermediates and final solid products of La2(CO3)3·3.4H2O from 30 to 1000 °C were characterized by XRD, FTIR and DTA-TG. The kinetics of dehydration of La2(CO3)3·3.4H2O in the temperature range of 30-366 °C was investigated under non-isothermal conditions. Flynn-Wall-Ozawa and Friedman isoconversion methods were used to calculate the activation energy and analyze the reaction steps; multivariate non-linear regression program was applied to determine the most probable mechanism and the kinetic parameters. The results show that the thermal dehydration of La2(CO3)3·3.4H2O is a kind of three-step competitive reaction, and controlled by an n-order initial reaction followed by n-order competitive reaction(FnFnFn model). The activation energy matching with the most probable model is close to value obtained by Friedman method. The fitting curves match the original TG-DTG curves very well. 展开更多
关键词 La2(CO3)3·3.4H2O non-isothermal kinetics simultaneous thermal analysis dehydration reaction
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Genetic Analysis of the VP2 Hypervariable Region of Thirty-six Infectious Bursal Disease Virus Isolates in China during 2009-2012 被引量:2
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作者 祁小乐 秦立廷 +10 位作者 高玉龙 高宏雷 李颖颖 高立 卢珍 王念 陈玉明 张礼洲 李凯 王永强 王笑梅 《Agricultural Science & Technology》 CAS 2015年第8期1565-1569,1602,共6页
[Objective] Infectious bursal disease (IBD) is a highly contagious immuno- suppressive disease caused by infectious bursal disease virus (IBDV). IBDV is ge- netically prone to mutation, which results in challenges... [Objective] Infectious bursal disease (IBD) is a highly contagious immuno- suppressive disease caused by infectious bursal disease virus (IBDV). IBDV is ge- netically prone to mutation, which results in challenges to the disease prevention and control. Thus, it is necessary to continuously monitor the prevalence of IBDV. [Method] 36 IBDVs were identified from ten provinces in China from 2009 to 2012. Partial fragments of VP2, including the hypervariable region (HVR), from new iso- lates were sequenced and analyzed through comparisons with published sequences of IBDV, including 18 strains isolated previously by our lab and 24 reference strains from China and around the world. [Result] Phylogenetic analysis showed a co-exis- tence of IBDV strains belonging to classic, variant, attenuated, and very virulent IB- DV (wlBDV) in China. wlBDVs remain the predominant strains in China and the new subgroup was emerging. Alignment analysis revealed several distinct amino acid mutations that might be involved in virulence or antigenicity variation. [Conclu- sion] The results offered evolutionary clues showing the emerging trend of obvious variations and diversity of IBDV in major poultry-producing regions of China particu- larly in recent years. These findings will contribute to a better understanding of the genetic evolution of IBDV. 展开更多
关键词 Genetic analysis VP2 Infectious bursal disease virus
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Determination and Analysis of Mitochondrial ND2 Gene Sequence of Anas platyrhynchos 被引量:4
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作者 涂剑锋 司方方 +1 位作者 邢秀梅 杨福合 《Agricultural Science & Technology》 CAS 2009年第3期46-49,共4页
[Objective] The study was to analyze the phylogenesis of Anas platyrhynchos. [Method] Complete sequence of mitochondrial ND2 gene of 4 Anas platyrhynchos was determined by direct DNA sequencing based on PCR products. ... [Objective] The study was to analyze the phylogenesis of Anas platyrhynchos. [Method] Complete sequence of mitochondrial ND2 gene of 4 Anas platyrhynchos was determined by direct DNA sequencing based on PCR products. Combined with ND2 gene sequences of the Anas Linnaeus accessed in GenBank, phylogenetic tree was constructed by Neighbor-joining and maximum parsimony methods. [Result] The ND2 gene sequences of 4 Anas platyrhynchos were identical(1 041 bp in length; the nucleotide contents of A, G, T, and C were 28.91%, 13.35%, 20.75% and 36.98% respectively; A+T content approximated to that of C+G). Sequences of ND2 gene of mallard were same as spotbill duck, and had high homology with others. The phylogenetic trees indicated mallard and spotbilled duck were close in genetic relationship, both shared a haplotype; then Philippine duck, green-winged teal and northern pintail fell into branch ''A". [Conclusion] The domestic duck may be domesticated from mallard and spotbilled duck. 展开更多
关键词 Anas platyrhynchos ND2 gene sequence analysis Phylogenetic tree
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Complete Genome Sequencing and Genetic Variation Analysis of Two H9N2 Subtype Avian Influenza Virus Strains 被引量:2
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作者 沈佳 章振华 +3 位作者 姜北宇 李林 景小冬 张建伟 《Agricultural Science & Technology》 CAS 2011年第2期291-294,共4页
[Objective] The study aimed to investigate the genetic variation characters of entire sequences between two H9N2 subtype avian influenza virus strains and other reference strains.[Method] The entire sequences of 8 gen... [Objective] The study aimed to investigate the genetic variation characters of entire sequences between two H9N2 subtype avian influenza virus strains and other reference strains.[Method] The entire sequences of 8 genes were obtained by using RT-PCR,and these sequences were analyzed with that of six H9N2 subtype avian influenza isolates in homology comparison and genetic evolution relation.[Result] The results showed that the nucleotide sequence of entire gene of the strain shared 91.1%-95.4% homology with other seven reference strains,and PG08 shared the highest homology 91.3% with C/BJ/1/94;ZD06 shared the highest homology 92.3% with D/HK/Y280/97.HA cleavage sites of two H9N2 subtype avian influenza virus isolated strains were PARSSR/GLF,typical of mildly pathogenic avian influenza virus.[Conclusion] Phylogenetic tree for entire gene of eight strains showed that the genetic relationship was the closest between ZD06 and C/Pak/2/99 strains,which belonged to the Eurasian lineage;PG08 shared the highest homology 91.3% with ZD06,it may be the product of gene rearrangements of other sub-lines. 展开更多
关键词 Avian influenza virus H9N2 subtype Complete genome Sequence analysis
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Sequence Analysis of HA Genes from Three H9N2 Subtype Avian Influenza Viruses 被引量:2
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作者 韩春华 林健 +3 位作者 刘月焕 潘洁 马明 刘永宏 《Animal Husbandry and Feed Science》 CAS 2009年第1期32-35,共4页
[ Objective] The study aimed to understand the genetic characters of H9N2 subtype avian influenza viruses isolated in Belling area. [ Method] HA genes of three H9N2 subtype avian influenza viruses A/Chicken/Beijing/xu... [ Objective] The study aimed to understand the genetic characters of H9N2 subtype avian influenza viruses isolated in Belling area. [ Method] HA genes of three H9N2 subtype avian influenza viruses A/Chicken/Beijing/xu/00, A/Chicken/Beijing/bei/00 and A/Chicken/Beijing/ liu/00 were amplified by RT-PCR and then sequenced. [ Result] The results of phylogenetic analysis showed that A/Chicken/Beijing/xu/00, A/ Chicken/Beijing/bei/00 and A/Chicken/Beijing/liu/00 shared the nucleotide homologies of 84.8% ( Dk/HK/Y439/97 ) -98.0% ( Ck/GX17/00 ), 85.1% (Dk/HK/Y439/97) - 99.1% ( Ck/GXl 7/00), 90.7% ( Ck/BJ/3/01 ) - 99.1% (Ck/GX17/00) with the isolates from Hongkong and other are- as of Chinese Mainland respectively. At the same time, the analysis of amino acid indicated that the three isolates belonged to low pathogenic H9N2 isolates of avian origin. The 226^th amino acid of them were L ( Leu), suggesting their high binding affinity to human cells. There were seven glyco- sylation sites in HA protein, five from HA1 and two from HA2. [ Cenclusien] By analysis at molecular level, it could be concluded that A/Chicken/ Beijing/xu/00, A/Chicken/Beijing/bei/00 and A/Chicken/Beijing/liu/00 were low pathogenic H9N2 isolates of avian origin. 展开更多
关键词 H9N2 subtype avian influenza virus HA gene Sequence analysis
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电厂粉煤灰、炉渣和污泥复合陶粒对低浓度Pb^(2+)的吸附特性 被引量:3
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作者 杨毅 高敏轩 +3 位作者 陈元 赵睿 舒麒麟 刘伟 《环境科学研究》 CAS CSCD 北大核心 2024年第2期407-414,共8页
针对重金属污染具有来源广、危害大等特点,通过以电厂废物(粉煤灰、炉渣)和脱水污泥为原料制备一种高效且价廉的陶粒吸附剂,采用吸附影响因素实验、解吸再生实验、吸附动力学模型和等温吸附模型的拟合以及陶粒表征分析,探究陶粒对Pb^(2+... 针对重金属污染具有来源广、危害大等特点,通过以电厂废物(粉煤灰、炉渣)和脱水污泥为原料制备一种高效且价廉的陶粒吸附剂,采用吸附影响因素实验、解吸再生实验、吸附动力学模型和等温吸附模型的拟合以及陶粒表征分析,探究陶粒对Pb^(2+)的吸附特性,同时为实现废物资源化利用提供新思路.结果表明:陶粒去除Pb^(2+)的较佳吸附条件为粒径4 mm、pH 4.5~5.0、吸附时间360 min、吸附温度25℃.陶粒再生所用较佳解吸剂为0.5 mol/L的HCl溶液,较佳解吸时间和次数分别为120 min和5次,解吸5次后陶粒对Pb^(2+)的去除率为92.67%.此吸附过程更好地遵循了准二级动力学模型和Freundlich等温吸附模型.陶粒上的O-H、Si-O和金属氧化键在吸附Pb^(2+)的过程中起主要作用.陶粒吸附Pb^(2+)后,出现了新的物相Pb_(2)Cl_(3)OH和PbO,陶粒与Pb^(2+)之间发生化学吸附,为自发进行的放热反应.陶粒处理实际废水中Pb^(2+)的去除率可达93.70%,Pb^(2+)浓度由3.74 mg/L降至0.24 mg/L.研究显示,电厂粉煤灰、炉渣和污泥复合陶粒对Pb^(2+)具有一定的去除效果,可为以固体废物为原料制备的吸附剂在重金属废水处理应用中提供数据支撑. 展开更多
关键词 电厂废物 污泥 陶粒 Pb^(2+) 表征分析 吸附特性
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黄铁矿在CO_(2)气氛下非等温氧化转化及动力学分析 被引量:1
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作者 黄芳 况怡婷 +3 位作者 张立麒 米铁 辛善志 刘晓烨 《燃烧科学与技术》 CAS CSCD 北大核心 2024年第1期82-90,共9页
针对煤中常见含铁矿物黄铁矿在富氧燃烧典型气氛下转化特性,通过同步热分析结合烟气分析研究了黄铁矿在CO_(2)气氛下的转化行为.结果发现,黄铁矿在CO_(2)气氛下主要经历5个失重阶段且均为吸热过程,首先是黄铁矿颗粒表面硫脱除的起始热解... 针对煤中常见含铁矿物黄铁矿在富氧燃烧典型气氛下转化特性,通过同步热分析结合烟气分析研究了黄铁矿在CO_(2)气氛下的转化行为.结果发现,黄铁矿在CO_(2)气氛下主要经历5个失重阶段且均为吸热过程,首先是黄铁矿颗粒表面硫脱除的起始热解段(相界面反应,n=1/2),活化能低于其在N_(2)气氛下近30 kJ/mol,为220.27 kJ/mol,随后裂解成磁黄铁矿(三维扩散,n=1/2)活化能与其在N_(2)(177.27 kJ/mol)下接近为178.1 kJ/mol;温度高于690℃,随着升温磁黄铁矿缓慢失硫,CO_(2)逐渐参与磁黄铁矿转化且释放SO_(2)和CO;820~1150℃经历双峰失重峰阶段,820~1020℃,氧化气体产物SO_(2)大量生成且在约1000℃达到体积浓度峰值;最后1020~1150℃,坩埚中残留物大量与CO_(2)持续氧化反应失重形成SO_(2)和CO,坩埚中形成复杂物相体系,铁硫化物和铁氧化物共存(或共融).CO_(2)参与黄铁矿产物转化失重阶段活化能分别为180.94 kJ/mol、229.69 kJ/mol和243.46 kJ/mol,动力学机制均为成核与生长(n=1). 展开更多
关键词 黄铁矿 非等温 CO_(2) 氧化转化 动力学
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GRA BASED ANALYSIS ON FACTORS INFLUENCING CO_2 EMISSIONS IN CHINA 被引量:1
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作者 董锋 李晓晖 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期152-158,共7页
How to achieve the objective of reducing CO2 emissions has been an academic focus in China recently. The factors influencing CO2 emissions are the vital issue to accomplish the arduous target. Firstly, three influenti... How to achieve the objective of reducing CO2 emissions has been an academic focus in China recently. The factors influencing CO2 emissions are the vital issue to accomplish the arduous target. Firstly, three influential factors, the energy consumption, the proportion of tertiary industry in gross domestic product (GDP), and the degree of dependence on foreign trade, are carefully selected, since all of them have closer grey relation with China's COz emissions compared with others when the grey relational analysis (GRA) method is applied. The study highlights co-integration relation of these four variables using the co-integration analysis method. And then a long-term co-integration equation and a short-term error correction model of China's CO2 emissions are devel- oped. Finally, the comparison is exerted between the forecast value and the actual value of China's CO2 emissions based on error correction model. The results and the relevant statistics tests show that the pro- posed model has better explanation capability and credibility. 展开更多
关键词 grey relational analysis(GRA) CO2 emissions co-integration test error correction model
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