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Application of FTIR two-dimensional correlation spectroscopy(2D-COS)analysis in characterizing environmental behaviors of microplastics:A systematic review
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作者 Shuang Peng Feipeng Wang +3 位作者 Dongbin Wei Cuiping Wang Haijun Ma Yuguo Du 《Journal of Environmental Sciences》 2025年第1期200-216,共17页
Microplastics(MPs)are ubiquitous in the environment,continuously undergo aging processes and release toxic chemical substances.Understanding the environmental behaviors of MPs is critical to accurately evaluate their ... Microplastics(MPs)are ubiquitous in the environment,continuously undergo aging processes and release toxic chemical substances.Understanding the environmental behaviors of MPs is critical to accurately evaluate their long-term ecological risk.Generalized twodimensional correlation spectroscopy(2D-COS)is a powerful tool for MPs studies,which can dig more comprehensive information hiding in the conventional one-dimensional spectra,such as infrared(IR)and Raman spectra.The recent applications of 2D-COS in analyzing the behaviors and fates of MPs in the environment,including their aging processes,and interactions with natural organicmatter(NOM)or other chemical substances,were summarized systematically.The main requirements and limitations of current approaches for exploring these processes are discussed,and the corresponding strategies to address these limitations and drawbacks are proposed as well.Finally,new trends of 2D-COS are prospected for analyzing the properties and behaviors of MPs in both natural and artificial environmental processes. 展开更多
关键词 Microplastics(MPs) 2d-cos application Aging processes INTERACTIONS
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Evaluation of the protective effects of Crocus sativus L.against cypermethrin induced reproductive toxicity in male rats through the Nrf2 pathway and in silico ADMET analysis
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作者 Fareena Tariq Farah Ijaz +9 位作者 Yasameen Hameed Jasim Farah Naz Channa Sohail Ahmed Ahmed Shandookh Hameed Sobia Alyas Ahmed Raheem Rayshan Tahira Bibi Nazima Yousaf Khan Sadia Bibi Jameel Ahmed Buzdar 《Traditional Medicine Research》 2026年第3期12-25,共14页
Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to i... Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to its therapeutic properties,but its exact role and molecular mechanisms in treatment of reproductive dysfunction remain unclear.Methods:During this study,36 rats were randomly divided into six groups(n=6):control,CYP-induced(60 mg/kg),standard(leuprolide 3 mg/kg)and three treatment groups receiving aqueous,ethanolic,and oil extracts(50 mg/kg or 20 mL/kg)for post-toxicity induction.Results:The finding represented that exposure of CYP significantly increased oxidative stress,disrupted testicular architecture,and markedly reduced testosterone levels(P<0.05).Importantly,Crocus sativus L.treatment alleviated these changes by increasing the expression of Nrf2(nuclear factor erythroid 2-related factor 2),restoring the activity of antioxidant enzymes,and enhancing testicular histomorphology.Surprisingly,molecular docking established a high binding affinity of Crocus sativus L.phytoconstituents such as gallic acid,cinnamic acid and quercetin to the Nrf2-Keap1 complex.It is worth noting that,Crocus sativus L.exhibited a high level of protection against reproductive toxicity caused by CYP in male rats,which was mediated by the activation of Nrf2 pathway,reduction of oxidative damage,and favorable ADMET characteristics.Conclusion:Notably,this research provides a more valid,safe,and effective method of developing new drugs for reproductive disorders,however,further investigation is needed to support the research findings and implement it in clinical practice. 展开更多
关键词 Crocus sativus L. CYPERMETHRIN male reproductive toxicity Nrf2 pathway in silico ADMET analysis
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基于2D-COS分析不同热解温度及分子量生物炭DOM的光谱特征
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作者 肖颖晨 汪王宇 +3 位作者 聂明华 晏彩霞 丁明军 陈洁 《环境科学学报》 北大核心 2025年第3期336-349,共14页
选取喜旱莲子草为生物炭原料,利用多种光谱技术和方法,探究不同热解温度(300~700℃)和分子量(0.3、1、3和10 kDa)生物炭溶解性有机质(BDOM)的理化特征,以期为生物炭的应用和入侵植物资源化利用提供理论依据.通过三维荧光光谱结合平行因... 选取喜旱莲子草为生物炭原料,利用多种光谱技术和方法,探究不同热解温度(300~700℃)和分子量(0.3、1、3和10 kDa)生物炭溶解性有机质(BDOM)的理化特征,以期为生物炭的应用和入侵植物资源化利用提供理论依据.通过三维荧光光谱结合平行因子分析法共解析出2个类腐殖质和1个类蛋白质组分,各热解温度BDOM总体均以类腐殖物质含量更高,随热解温度升高类蛋白物质百分比逐渐增加.二维相关图谱(2D-COS)结合同步荧光光谱(SFS)分析结果表明,类富里酸对热解温度变化较敏感,并以类腐殖质组分的变化更早;而结合傅里叶变换红外光谱(FTIR)的分析结果表明,酚类和酰胺类物质随热解温度变化的方向不同且快于其他官能团.移动窗口2D-COS分析结果表明,500℃时荧光物质和官能团的响应最强.当透析袋孔径为6 kDa左右时,各BDOM体系荧光组分的变化最显著.而基于SFS-FTIR的Hetero-2DCOS分析表明,主要官能团与类富里酸均随热解温度发生变化,其中,N−H(酰胺II)的变化快于类富里酸,但方向相反.此外,不同分子量BDOM透析过程中,低热解温度以类络氨酸组分较敏感,而高热解温度以类富里酸组分更敏. 展开更多
关键词 生物炭溶解性有机质(BDOM) 热解温度 分子量 光谱分析 二维相关图谱分析(2d-cos)
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Characterization of petrophysical and seismic properties for CO_(2)storage with sensitivity analysis 被引量:1
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作者 Yan-Jiao Dong Yi Shen +4 位作者 Kai Guo Xiao-Qin Wu Qiang Mao Wen-Yue Sun Zhi-Qiang Wang 《Petroleum Science》 2025年第1期193-209,共17页
Saline aquifers are considered as highly favored reservoirs for CO_(2)sequestration due to their favorable properties.Understanding the impact of saline aquifer properties on the migration and distribution of CO_(2)pl... Saline aquifers are considered as highly favored reservoirs for CO_(2)sequestration due to their favorable properties.Understanding the impact of saline aquifer properties on the migration and distribution of CO_(2)plume is crucial.This study focuses on four key parameters-permeability,porosity,formation pressure,and temperature-to characterize the reservoir and analyse the petrophysical and elastic response of CO_(2).First,we performed reservoir simulations to simulate CO_(2)saturation,using multiple sets of these four parameters to examine their significance on CO_(2)saturation and the plume migration speed.Subsequently,the effect of these parameters on the elastic properties is tested using rock physics theory.We established a relationship of compressional wave velocity(V_(p))and quality factor(Q_(p))with the four key parameters,and conducted a sensitivity analysis to test their sensitivity to V_(p) and Q_(p).Finally,we utilized visco-acoustic wave equation simulated time-lapse seismic data based on the computed V_(p) and Q_(p) models,and analysed the impact of CO_(2) saturation changes on seismic data.As for the above nu-merical simulations and analysis,we conducted sensitivity analysis using both homogeneous and heterogeneous models.Consistent results are found between homogeneous and heterogeneous models.The permeability is the most sensitive parameter to the CO_(2)saturation,while porosity emerges as the primary factor affecting both Q_(p) and V_(p).Both Q_(p) and V_(p) increase with the porosity,which contradicts the observations in gas reservoirs.The seismic simulations highlight significant variations in the seismic response to different parameters.We provided analysis for these observations,which serves as a valuable reference for comprehensive CO_(2)integrity analysis,time-lapse monitoring,injection planning and site selection. 展开更多
关键词 CO_(2)storage Time-lapse seismic CO_(2)plume Sensitivity analysis Rock physics Reservoir simulation Saline aquifer
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Complete Genomic Sequence Analysis of Sweet Potato Virus 2 Isolates from the Shandong and Jiangsu Provinces in China
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作者 Zichen Li Jukui Ma +2 位作者 Minjun Liu Guowei Geng Hongxia Zhang 《Phyton-International Journal of Experimental Botany》 2025年第6期1841-1856,共16页
Sweet potatoes are significant cash crops,however,their yield and quality are greatly compromised by viral diseases.In this study,the complete genomic sequences of two Sweet Potato Virus 2(SPV2)isolates from infected ... Sweet potatoes are significant cash crops,however,their yield and quality are greatly compromised by viral diseases.In this study,the complete genomic sequences of two Sweet Potato Virus 2(SPV2)isolates from infected sweet potato leaves in the Shandong(designated as SPV2-SDYT,GenBank No.PQ855660.1)and Jiangsu(designated as SPV2-JSXZ,GenBank No.PQ855661.1)provinces in China were obtained using 5′RACE and RT-PCR amplification.Consistency,phylogeny,codon usage bias,recombination,and selection pressure analyses were conducted using the SPV2-SDYT and SPV2-JSXZ genome sequences.The complete genome sequences of SPV2-SDYT and SPV2-JSXZ were 10561 nucleotides(nt)in length,with respective nucleotide and amino acid identities of 99.25%and 99.12%,respectively.Both isolates were closely related to the SPV2 isolate from China(SPV2-LN).In both SPV2-SDYT and SPV2-JSXZ,the identity of the P1 protein was the highest,whereas that of the P3 protein was the lowest.There were 26 codons with relatively synonymous codon usage(RSCU)values greater than 1 in SPV2-SDYT and 27 codons with RSCU values greater than 1 in SPV2-JSXZ.High-frequency codons in their genomes were predominantly found to end with A/U.Recombination analysis revealed no major recombination sites in either SPV2-SDYT or SPV2-JSXZ.Further selection pressure analysis showed that the non-synonymous substitution rate/synonymous substitution rate(dN/dS)value of all 10 SPV2 proteins was less than 1.This is the first report on the evolutionary relationships of the 17 known SPV2 isolates.Our findings lay the molecular groundwork for preventing and controlling SPV2 infection in root-tuber crops.These findings also contribute to our understanding of the spread and evolution of SPV2,its pathogenic mechanisms,and the development of antiviral strategies against it. 展开更多
关键词 Sweet potato virus 2 consistency analysis phylogenetic analysis codon usage bias analysis recombination analysis selection pressure analysis
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Impact of biochars on CO_(2) emissions and physic-chemical properties in Malaysian Tropical soils:Factor analysis and weighted contribution
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作者 Xingxing Cheng Chiu Chuen Onn +4 位作者 Faridah Othman Rosazlin Abdullah Wenxian Guo Priscilla Fong Ern Gunn Liang Yue 《Journal of Environmental Sciences》 2025年第12期84-97,共14页
Global climate change is the most serious challenge that modern society faces.Soil-biochar carbon sequestration is a promising natural solution for capturing carbon.This study monitored the CO_(2) emissions of five bi... Global climate change is the most serious challenge that modern society faces.Soil-biochar carbon sequestration is a promising natural solution for capturing carbon.This study monitored the CO_(2) emissions of five biochar incubated Malaysian Tropical soils(MT-Soil).The recalcitrance index of palm kernel shell biochar(PKS)was higher than that of wood chip biochar(WCB),bamboo biochar(BB),coconut shell biochar(CHB)and rice husk biochar(RHB),and was different from the observed CO_(2) emission characteristics(WCB>CHB>RHB>BB>PKS).Thus,the carbon sequestration potential of biochar could not be evaluated solely by the recalcitrance index.This CO_(2) emission is linked not only to the total organic carbon(TOC)and total carbon(TC)of the biochar but also associated with mobile matter(MM),water holding capacity(WHC),available phosphorus(AP),exchangeable potassium(AK),and nitrogen content.The multiple linear regression analysis(MLRA)shows that the weights of these factors on CO_(2) emissions are as follows:TC>pH>MM>WHC>AP>AK.The results show that in addition to biochar stability,pore structure and available phosphorus release also affect carbon dynamics through indirect effects on microbial activity.This means that to minimize CO_(2) emissions during application of biochar,it is necessary to use soil that is rich in phosphorus and biochar that has undeveloped pore structure and high stable carbon.Finally,this study provides valuable theoretical underpinnings biochar application in MT-Soil. 展开更多
关键词 Biochar soil Physic-chemical properties CO_(2) emission Correlation analysis
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Genome-wide association analysis reveals regulatory genes for the metabolite synthesis of 2-acetyl-1-pyrroline in aromatic coconut(Cocos nucifera L.)
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作者 Hao Ding Xiang Lv +5 位作者 Guangzhen Zhou Xiaomei Liu Xiwei Sun Jing Li Amjad Iqbal Yaodong Yang 《Journal of Genetics and Genomics》 2025年第2期179-188,共10页
Coconut(Cocos nucifera L.)is a key tropical economic tree valued for its fruit flavor,particularly 2-acetyl-1-pyrroline(2AP),a vital aroma metabolite.To enhance high-aromatic coconut breeding efforts,it is essential t... Coconut(Cocos nucifera L.)is a key tropical economic tree valued for its fruit flavor,particularly 2-acetyl-1-pyrroline(2AP),a vital aroma metabolite.To enhance high-aromatic coconut breeding efforts,it is essential to deeply understand the hereditary factors governing the production of 2AP.In this study,a genome-wide association analysis identifies 32 loci that exhibit significant associations with 2AP content based on single nucleotide polymorphism(SNP)variations from 168 aromatic coconut germplasm resources.Transcriptome analysis then pinpoints 22 candidate genes near significant loci involved in 2AP metabolism.Proteins encoded by these genes are involved in amino acid metabolism,glycolysis,and secondary metabolism.Among these,Asparagine synthetase coding gene ASN1,Gamma-glutamylcysteine synthetase coding gene GSH1,and UbiA prenyltransferase coding gene UBIA are enriched in the linkage region constructed by significant locus Chr04_61490504.In particular,the SNP mutation of CnASN1 leads to amino acid changes in the functional region of the coding protein,potentially resulting in differences in 2AP content among haplotype populations.Identifying variations in related candidate genes,particularly the gene CnASN1,provides molecular markers closely associated with 2AP synthesis for coconut breeding and offers further insights into the metabolic mechanisms of 2AP. 展开更多
关键词 Aromatic coconut 2AP SNP Genome-wideassociation study(GWAS) Haplotype analysis
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Analysis of inflammatory response and its factors after dental implant surgery in patients with type 2 diabetes
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作者 Zhang-Yi Li Heng-Yang Yu Hong Liang 《World Journal of Diabetes》 2025年第10期238-248,共11页
BACKGROUND Dental implants are widely used to replace missing teeth.Currently,clinicians assess osseointegration success by measuring the implant’s stability within the bone and monitoring the marginal tissue height.... BACKGROUND Dental implants are widely used to replace missing teeth.Currently,clinicians assess osseointegration success by measuring the implant’s stability within the bone and monitoring the marginal tissue height.Diabetes,especially type 2 diabetes mellitus(T2DM),has been reported to impair implant healing,drastically reducing implant success rates.AIM To analyze the high-risk factors for inflammatory response and prognosis after dental implantation in patients with T2DM,and provide strong evidence for reducing the incidence of postimplant peri-implantitis(PI).METHODS We performed a retrospective review of 146 patients with T2DM who had dental implants placed at Tianjin Fifth Central Hospital,between September 2021 and September 2023,which was regarded as the observation group.Moreover,60 ageand gender-matched individuals with normal blood glucose levels served as the control group.The general information,postoperative periodontal indices,and levels of inflammatory factors were comprehensively analyzed and compared.Furthermore,the incidence of postimplant PI was counted,and multivariate logistic regression was used to identify the determinants of postimplant PI.RESULTS In terms of the periodontal indices,the probing depth,modified sulcus bleeding index,and marginal bone loss in the observation cohorts began to increase significantly at 6 months and 3 months,respectively,after the completion of dental implant restoration.The T2DM cases demonstrated significantly elevated counts of leukocytes,lymphocytes,and neutrophils compared to the controls at 24 hours postoperatively.Moreover,the TNF-α,IL-1β,and IL-6 concentrations started to increase significantly in the gingival crevicular fluid 3 months after the completion of dental implant restoration in both cohorts,with the observation group exhibiting higher levels than the controls at each time point.63 out of the 146 cases developed PI.Multivariate logistic regression analysis indicated that high glycosylated hemoglobin levels,smoking,daily tooth-brushing frequency of less than once,and the anterior tooth as the implant site independently contributed to postimplant PI in T2DM cases,while a tooth-brushing duration of≥3 minutes was a protective factor.CONCLUSION Patients with T2DM are at risk of developing PI following dental implantation.Clinically,it is necessary to enhance the identification of risk factors for postimplant PI,improve risk prediction,prevention,and control,and formulate targeted intervention countermeasures to reduce the occurrence of postimplant PI. 展开更多
关键词 Type 2 diabetes mellitus Dental implants Inflammatory response Factor analysis Periodontal prognosis
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Scientometric analysis and historical review of diabetic encephalopathy research:Trends and hotspots(2004-2023)
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作者 Xian-Wen Ye Hai-Xia Zhang +10 位作者 Qian Li Chun-Shuai Li Chong-Jun Zhao Liang-Jing Xia Hong-Min Ren Xu-Xing Wang Chao Yang Yu-Jie Wang Shui-Lan Jiang Xin-Fang Xu Xiang-Ri Li 《World Journal of Diabetes》 2025年第5期423-447,共25页
BACKGROUND Diabetic encephalopathy(DE)is a common and serious complication of diabetes that can cause death in many patients and significantly affects the lives of individuals and society.Multiple studies investigatin... BACKGROUND Diabetic encephalopathy(DE)is a common and serious complication of diabetes that can cause death in many patients and significantly affects the lives of individuals and society.Multiple studies investigating the pathogenesis of DE have been reported.However,few studies have focused on scientometric analysis of DE.AIM To analyze literature on DE using scientometrics to provide a comprehensive picture of research directions and progress in this field.METHODS We reviewed studies on DE or cognitive impairment published between 2004 and 2023.The latter were used to identify the most frequent keywords in the keyword analysis and explore the hotspots and trends of DE.RESULTS Scientometric analysis revealed 1308 research papers on DE,a number that increased annually over the past 20 years,and that the primary topics explored were domain distribution,knowledge structure,evolution,and emergence of research topics related to DE.The inducing factors,comorbidities,pathogenesis,treatment,and animal models of DE help clarify its occurrence,development,and treatment.An increasing number of studies on DE may be a result of the recent increase in patients with diabetes,unhealthy lifestyles,and unhealthy eating habits,which have aggravated the incidence of this disease.CONCLUSION We identified the main inducing factors and comorbidities of DE,though other complex factors undoubtedly increase social and economic burdens.These findings provide vital references for future studies. 展开更多
关键词 Diabetic encephalopathy Type 2 diabetes mellitus Cognitive impairment Scientometric analysis Research hotspots
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Meat products consumption and risk for Alzheimer’s dementia and type 2 diabetes:a systematic review and meta-analysis of cohort studies
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作者 Mingyu Li Xiaoyue Yang +6 位作者 Lu Sun Hongwei Xiao Chongxin Liu Chunjiang Zhang Zhenyu Wang Christophe Blecker Dequan Zhang 《Food Science and Human Wellness》 2025年第8期2929-2944,共16页
Alzheimer’s dementia(AD)and type 2 diabetes(T2D)are interrelated global public health problems,and the current epidemics of both AD and T2D are insulin resistance diseases.Thus,AD and T2D may share common risk factor... Alzheimer’s dementia(AD)and type 2 diabetes(T2D)are interrelated global public health problems,and the current epidemics of both AD and T2D are insulin resistance diseases.Thus,AD and T2D may share common risk factors such as an unhealthy diet,lifestyle,and obesity.Meat products is an important part of the diet of consumers worldwide.This systematic review and meta-analysis aims to assess and estimate the effect of meat products consumption on AD and T2D in humans.Web of Science,MEDLINE,PubMed,Cochrane Library,and Embase were searched from January 2012 to April 2024.29 articles reported 32 cohort studies with 1785769 subjects,with 3546 AD cases and 91092 T2D cases that met the inclusion criteria and were included in our analysis.Consumption of various meat products increased the risk of T2D(hazard ratios(HR)=1.19,95%confidence intervals(CI):1.13−1.26,P=0.000;I2=88.5%),consumption of smoked,grilled/roasted and fried meat products was more likely to induce T2D(HR=1.24,95%CI:1.18−1.30,P=0.000;I2=76.1%),but was borderline significant for the risk of AD(HR=1.11,95%CI:0.98−1.25,P=0.094;I2=58.8%),with consumption of mainly livestock and poultry products increasing the risk(HR=1.21,95%CI:1.03−1.42,P=0.017;I2=66.8%).The association between meat products consumption and AD risk was influenced by meat type and sample size,while the risk of T2D was influenced by meat type,follow-up and sex.A daily intake of 27,123 and 170 g of livestock products increased the risk of T2D by 10%,51%and 70%respectively,whereas the risk of T2D was reduced when the intake of various meat products was less than 23 g/day. 展开更多
关键词 Meat products META-analysis Dose-response analysis Alzheimer’s dementia Type 2 diabetes Food safety
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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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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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Cloning and Sequence Analysis of Interferon γ-2β Full-length cDNA in Cyprinus carpio L.
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作者 陈义龙 冯祥汝 +6 位作者 赵晓 王文东 张俊辉 杨振国 孙真 贾生美 卢强 《Agricultural Science & Technology》 CAS 2012年第6期1230-1233,共4页
[Objective] The research aimed to carry out the cloning, identification and sequence analysis of full-length cDNA of carp interferon γ-2β (IFNγ-2β). [Method] The cDNA library of peripheral blood leucocytes which... [Objective] The research aimed to carry out the cloning, identification and sequence analysis of full-length cDNA of carp interferon γ-2β (IFNγ-2β). [Method] The cDNA library of peripheral blood leucocytes which were separated from carp and stimulated with mitogen was screened by a probe labeled with DIG. The IFNγ- 2β EST sequence was picked out from the constructed cDNA library of peripheral blood leucocyte, and the full length of carp interferon γ-2β was cloned. In addition, the sequence analysis was carried out. [Result] Three positive clones were obtained. Sequence analysis indicated that the sequence had a 119 bp 5’-UTR and a 218 bp 3’-UTR, and the open reading frame (ORF)of this gene was 537 bp which putatively coded 178 amino acids and there were several instable motifs for mRNA (ATTTA) in the 3’-untranslated region. Its homology with IFN from GenBank was up to 97% . Analysis on protein sequence and structure showed that the predicted protein sequence was identified as an IFN family signature. [Conclusion] The research laid the foundation for further studying the expression manner, function characteristic and regulation mechanism of IFNγ-2β in vivo and the action mechanism in the inflammatory reaction, emergency reaction and immune response. 展开更多
关键词 Common carp Interferon gamma-2β CLONING Sequencing analysis
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Sequence Comparison and Analysis of HA Gene of Four H9N2 Avian Influenza Virus Isolates
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作者 章振华 于博 +4 位作者 姜北宇 钱爱东 李林 景小冬 张建伟 《Agricultural Science & Technology》 CAS 2009年第5期55-58,64,共5页
[ Objective] To determine the HA gene sequences of four H9N2 Avian influenza virus (AIV) strains and carry out comparative analysis so as to understand the difference and variation pattern of each strain from the an... [ Objective] To determine the HA gene sequences of four H9N2 Avian influenza virus (AIV) strains and carry out comparative analysis so as to understand the difference and variation pattern of each strain from the angle of molecular biology and to know the distribution and epidemic law of H9N2 AIV. [Method] One pair of primers was designed referring to HA gene sequences of H9N2 AIV. The HA genes of A/Chicken/Hebei/WD/98 (H9N2; WD98 for short), A/Chicken/Hebei/ZD/04 (H9N2; ZD04 for short)), A/Chicken/Beijing/MY/06 (H9N2; MY06 for short) ), and A/Chicken/Beijing/PG/08 (H9N2; PG08 for short)) were amplified, cloned and sequenced. Then the HA gene sequences of these strains were compared with that of 10 H9N2 AIV stains in GenBank. [Result] The ORF of HA genes of the four strains was 1 683 bp in size, encoding 516 amino acids. The HA gene sequences of the four strains, WD98, MY06, PG08, and ZD04, were 82.6% -95.1%, 83.0% -99.0%, 82.7% -95.5%, and 81.3% -95.7% homologous to that of the 10 H9N2 AIV stains, respectively. And the homology of amino acid was respectively 86.6% -96.3%, 86.6% -97.9%, 87.0% -97.1%, and 86.9% -97.3%. [ Conclusion] The HA gene has greatly high homology among different strains. 展开更多
关键词 Avian influenza H9N2 Sequence analysis Hemagglutinin gene
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Cloning and Phylogenetic Analysis of NS1 Genes from Different Isolates of H9N2 Subtype Duck Influenza Virus
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作者 谢青梅 张祥斌 +3 位作者 吴志强 冀君 周科 毕英佐 《Agricultural Science & Technology》 CAS 2009年第1期64-67,126,共5页
[ Objective] The study aimed to lay a foundation for the further studies on function mechanism of NS1 protein in the interspecies transmission of waterfowl influenza virus. [Method] Using the serologic assay and the s... [ Objective] The study aimed to lay a foundation for the further studies on function mechanism of NS1 protein in the interspecies transmission of waterfowl influenza virus. [Method] Using the serologic assay and the specific RT-PCR method, some strains of H9 subtype waterfowl influenza virus were isolated from the 12 to 20 day-old muscovy duck flocks without any clinical symptoms in different areas of Guangdong Province. Four of these strains, including A/duck/ZQ/303/2007(H9N2) (A3 for short), A/Duck/FJ/301/2007 (H9N2) (C1 for short), A/Duck/NH/306/2007(H9N2) ( D6 for short), A/duck/SS/402/2007(H9N2) ( E2 for short), and a strain named A/duck/ZC/2007(H9N2) (L1 for short) from a muscovy duck died of avian influenza virus (AIV), were used for NSl gene cloning and sequencing. Subsequently, the obtained NSl gene sequences were compared with other NS1 sequences registered in GenBank, and the phylogenetic analysis was also conducted. [Result] When compared with the H9N2 AIV NS1 sequences in GenBank, the NSl genes of the four AIV strains A3, C1, 136 and E2 displayed homologies ranging from 99% to 100% at nucleotide level, and 95% to 100% at amino acid level; while the NSl gene of L1 strain displayed homology ranging from 94% to 97% at nucleotide level, and 93% to 98% at amino acid level. The phylogenetic tree demonstrated that A3, C1, D6 and E2 were highly resemblant, and L1 was closest to AY66473 (chicken, 2003). By comparison with the NS1 gene sequences of L1, AF523514 (duck), AY664743 (chicken) and EF155262.1 (quail) using DNAstar, A3, C1, D6 and E.2 presented nucleotide variations at site 21 ( R→Q), 70, 71 ( KE→EG), 86 ( A→S), 124 (V→M) and 225 ( S→N), and amino acid variations at site 21,70, 71 and 86 in dsRNA- dependent protein kinase (PKR) binding domain of NSl gene, which induced the evident variations of antigenic determinant and surface proba- bility plot of NS1 protein. [ Conclusion] This study suggested that the amino acid sequence variation in PKR binding domain of NS1 protein had something to do with the virus pathogenicity. 展开更多
关键词 H9N2 subtype Duck influenza virus NS1 gene PKR Phylogenetic analysis
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Molecular Cloning and Sequence Analysis ofBoPGIP2 Gene from Brassica oleracea L. var. alboglabra
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作者 张弢 《Agricultural Science & Technology》 CAS 2009年第4期91-95,104,共6页
PGIP gene was obtained from Brassica oleracea L. var. alboglabra, named BoPGIP2. The full length of BoPGIP2 gene is 1 102 bp and the exon is 993 bp which encodes a protein of 330 amino acids with a predicted molecular... PGIP gene was obtained from Brassica oleracea L. var. alboglabra, named BoPGIP2. The full length of BoPGIP2 gene is 1 102 bp and the exon is 993 bp which encodes a protein of 330 amino acids with a predicted molecular mass of 37.1 kDa, interrupted by one intron of 95 bp in, length. Sequence analysis revealed that it has five potential N-giycosylation sites, two protein kinase C phosphrylation sites, five casin kinase Ⅱ phosphrylation sites and four N-myristoylation sites. The amino acids sequences alignment confirmed that ^145 LRR stucture was highly conserved in all aligned PGIP sequences. 展开更多
关键词 Brassica oleracea L. vat. alboglabra BoPGIP2 Molecular cloning Sequence analysis
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Differential Diagnostic Value of Texture Feature Analysis of Magnetic Resonance T2 Weighted Imaging between Glioblastoma and Primary Central Neural System Lymphoma 被引量:5
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作者 王波涛 刘明霞 陈志晔 《Chinese Medical Sciences Journal》 CAS CSCD 2019年第1期10-17,共8页
Objective To investigate the difference in tumor conventional imaging findings and texture features on T2 weighted images between glioblastoma and primary central neural system(CNS) lymphoma. Methods The pre-operative... Objective To investigate the difference in tumor conventional imaging findings and texture features on T2 weighted images between glioblastoma and primary central neural system(CNS) lymphoma. Methods The pre-operative MRI data of 81 patients with glioblastoma and 28 patients with primary CNS lymphoma admitted to the Chinese PLA General Hospital and Hainan Hospital of Chinese PLA General Hospital were retrospectively collected. All patients underwent plain MR imaging and enhanced T1 weighted imaging to visualize imaging features of lesions. Texture analysis of T2 weighted imaging(T2 WI) was performed by use of GLCM texture plugin of ImageJ software, and the texture parameters including Angular Second Moment(ASM), Contrast, Correlation, Inverse Difference Moment(IDM), and Entropy were measured. Independent sample t-test and Mann-Whitney U test were performed for the between-group comparisons, regression model was established by Binary Logistic regression analysis, and receiver operating characteristic(ROC) curve was plotted to compare the diagnostic efficacy. Results The conventional imaging features including cystic and necrosis changes(P = 0.000), ‘Rosette' changes(P = 0.000) and ‘incision sign'(P = 0.000), except ‘flame-like edema'(P = 0.635), presented significantly statistical difference between glioblastoma and primary CNS lymphoma. The texture features, ASM, Contrast, Correlation, IDM and Entropy, showed significant differences between glioblastoma and primary CNS lympoma(P = 0.006,0.000, 0.002, 0.000, and 0.015 respectively). The area under the ROC curve was 0.671, 0.752, 0.695, 0.720 and 0.646 respectively, and the area under the ROC curve was 0.917 for the combined texture variables(Contrast, cystic and necrosis, ‘Rosette' changes, and ‘incision sign') in the model of Logistic regression. Binary Logistic regression analysis demonstrated that cystic and necrosis changes, ‘Rosette' changes and ‘incision sign' and texture Contrast could be considered as the specific texture variables for the differential diagnosis of glioblastoma and primary CNS lymphoma. Conclusion The texture features of T2 WI and conventional imaging findings may be used to distinguish glioblastoma from primary CNS lymphoma. 展开更多
关键词 GLIOBLASTOMA primary CENTRAL NEURAL system LYMPHOMA texture analysis T2 WEIGHTED imaging differential diagnosis
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