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Cigar孤立子上加权散度型椭圆算子的特征值估计
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作者 孙玉涵 孙和军 《数学杂志》 2024年第2期113-125,共13页
本文研究了cigar孤立子(R 2,g,f)上加权散度型椭圆算子LA,f的如下Dirichlet特征值问题:{LA,f u+V u=λρu,inΩ,u=0,on∂Ω,其中V和ρ分别是Ω上的非负连续函数和正连续函数.我们建立了该问题的一些特征值不等式.
关键词 cigar孤立子 加权散度型椭圆算子 特征值
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Evidence relating cigarettes,cigars and pipes to cardiovascular disease and stroke:Meta-analysis of recent data from three regions
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作者 Peter Nicholas Lee Katharine J Coombs Jan S Hamling 《World Journal of Meta-Analysis》 2023年第6期290-312,共23页
BACKGROUND More recent data are required relating to disease risk for use of various smoked products and of other products containing nicotine.Earlier we published metaanalyses of recent results for chronic obstructiv... BACKGROUND More recent data are required relating to disease risk for use of various smoked products and of other products containing nicotine.Earlier we published metaanalyses of recent results for chronic obstructive pulmonary disease and lung cancer on the relative risk(RR)of current compared to never product use for cigarettes,cigars and pipes based on evidence from North America,Europe and Japan.We now report corresponding up-to-date evidence for acute myocardial infarction(AMI),ischaemic heart disease(IHD)and stroke.AIM To estimate,using recent data,AMI,IHD and stroke RRs by region for current smoking of cigarettes,cigars and pipes.METHODS Publications in English from 2015 to 2020 were considered that,based on epidemiological studies in the three regions,estimated the current smoking RR of AMI,IHD or stroke for one or more of the three products.The studies should involve at least 100 cases of stroke or cardiovascular disease(CVD),not be restricted to populations with specific medical conditions,and should be of cohort or nested case-control study design or randomized controlled trials.A literature search was conducted on MEDLINE,examining titles and abstracts initially,and then full texts.Additional papers were sought from reference lists of selected papers,reviews and meta-analyses.For each study identified,we entered the most recent available data on current smoking of each product,as well as the characteristics of the study and the RR estimates.Combined RR estimates were derived using random-effects meta-analysis for stroke and,in the case of CVD,separately for IHD and AMI.For cigarette smoking,where far more data were available,heterogeneity was studied by a wide range of factors.For cigar and pipe smoking,a more limited heterogeneity analysis was carried out.A more limited assessment of variation in risk by daily number of cigarettes smoked was also conducted.RESULTS Current cigarette smoking:Ten studies gave a random-effects RR for AMI of 2.72[95%confidence interval(CI):2.40-3.08],derived from 13 estimates between 1.47 and 4.72.Twenty-three studies gave an IHD RR of 2.01(95%CI:1.84-2.21),using 28 estimates between 0.81 and 4.30.Thirty-one studies gave a stroke RR of 1.62(95%CI:1.48-1.77),using 37 estimates from 0.66 to 2.91.Though heterogeneous,only two of the overall 78 RRs were below 1.0,71 significantly(P<0.05)exceeding 1.0.The heterogeneity was only partly explicable by the factors studied.Estimates were generally higher for females and for later-starting studies.They were significantly higher for North America than Europe for AMI,but not the other diseases.For stroke,the only endpoint with multiple Japanese studies,RRs were lower there than for Western studies.Adjustment for multiple factors tended to increase RRs.Our RR estimates and the variations by sex and region are consistent with earlier meta-analyses.RRs generally increased with amount smoked.Current cigar and pipe smoking:No AMI data were available.One North American study reported reduced IHD risk for non-exclusive cigar or pipe smoking,but considered few cases.Two North American studies found no increased stroke risk with exclusive cigar smoking,one reporting reduced risk for exclusive pipe smoking(RR 0.24,95%CI:0.06-0.91).The cigar results agree with an earlier review showing no clear risk increase for IHD or stroke.CONCLUSION Current cigarette smoking increases risk of AMI,IHD and stroke,RRs being 2.72,2.01 and 1.62.The stroke risk is lower in Japan,no increase was seen for cigars/pipes. 展开更多
关键词 cigarettes cigarS PIPES Cardiovascular disease STROKE META-ANALYSIS Review
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Evidence relating cigarette,cigar and pipe smoking to lung cancer and chronic obstructive pulmonary disease:Meta-analysis of recent data from three regions
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作者 Peter Nicholas Lee Katharine J Coombs Jan S Hamling 《World Journal of Meta-Analysis》 2023年第5期228-252,共25页
BACKGROUND There is a need to have up-to-date information for various diseases on the risk related to the use of different smoked products and the use of other nicotinecontaining products.Here,we contribute to the inf... BACKGROUND There is a need to have up-to-date information for various diseases on the risk related to the use of different smoked products and the use of other nicotinecontaining products.Here,we contribute to the information pool by presenting up-to-date quantitative evidence for North America,Europe and Japan and for both lung cancer and chronic obstructive pulmonary disease(COPD)on the relative risk(RR)relating to current vs never product use for each of the three smoked tobacco products,cigarettes,cigars and pipes.AIM To estimate lung cancer and COPD current smoking RRs for the three products using recent data for the three regions.METHODS Publications in English from 2010 to 2020 were considered that,based on epidemiological studies in the three regions,estimated the current smoking RR of lung cancer and/or COPD for one or more of the three products.The studies should involve at least 100 cases of the disease considered,not be restricted to specific lung cancer types or populations with specific medical conditions,and should be of cohort or nested case-control study design or randomized controlled trials.Literature searches were conducted on MEDLINE separately for lung cancer and for COPD,examining titles and abstracts initially,and then full texts.Additional papers were sought from reference lists of selected papers,reviews and metaanalyses.For each study identified,the most recent available data on each product were entered on current smoking,as well as on characteristics of the study and the RR estimates.Combined RR estimates were derived using random-effects meta-analysis.For cigarette smoking,where far more data were available,heterogeneity was studied by a wide range of factors.For cigar and pipe smoking,a more limited heterogeneity analysis was carried out.Results were compared with those from previous meta-analyses published since 2000.RESULTS Current cigarette smoking:For lung cancer,44 studies(26 North American,14 European,three Japanese,and one in multiple continents),gave an overall estimate of 12.14[95%confidence interval(CI)10.30-14.30].The estimates were higher(heterogeneity P<0.001)for North American(15.15,CI 12.77-17.96)and European studies(12.30,CI 9.77-15.49)than for Japanese studies(3.61,CI 2.87-4.55),consistent with previous evidence of lower RRs for Asia.RRs were higher(P<0.05)for death(14.85,CI 11.99-18.38)than diagnosis(10.82,CI 8.61-13.60).There was some variation(P<0.05)by study population,with higher RRs for international and regional studies than for national studies and studies of specific populations.RRs were higher in males,as previously reported,the within-study male/female ratio of RRs being 1.52(CI 1.20-1.92).RRs did not vary significantly(P≥0.05)by other factors.For COPD,RR estimates were provided by 18 studies(10 North American,seven European,and one Japanese).The overall estimate of 9.19(CI 6.97-12.13),was based on heterogeneous data(P<0.001),and higher than reported earlier.There was no(P>0.1)variation by sex,region or exclusive use,but limited evidence(0.05<P<0.1)that RR estimates were greater where cases occurring shortly after baseline were ignored;where bronchiectasis was excluded from the COPD definition;and with greater confounder adjustment.Within-study comparisons showed adjusted RRs exceeded unadjusted RRs.Current cigar smoking:Three studies gave an overall lung cancer RR of 2.73(CI 2.36-3.15),with no heterogeneity,lower than the 4.67(CI 3.49-6.25)reported in an earlier review.Only one study gave COPD results,the RR(2.44,CI 0.98-6.05)being imprecise.Current pipe smoking:Four studies gave an overall lung cancer RR of 4.93(CI 1.97-12.32),close to the 5.20(CI 3.50-7.73)given earlier.However,the estimates were heterogeneous,with two above 10,and two below 3.Only one study gave COPD results,the RR(1.12,CI 0.29-4.40),being imprecise.For both diseases,the lower RR estimates for cigars and for pipes than for current smoking of cigarettes aligns with earlier published evidence.CONCLUSION Current cigarette smoking substantially increases lung cancer and COPD risk,more so in North America and Europe than Japan.Limited evidence confirms lower risks for cigars and pipes than cigarettes. 展开更多
关键词 cigarettes cigarS Pipes Lung cancer META-ANALYSIS Review
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Carbon footprint accounting for cigar production processes: A life cycle assessment perspective
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作者 Guanzhun Cao Xiaoyao Guo +8 位作者 Chuan Feng Tong Li Feng Cui Yuan Xu Shuo Yang Qingsong Wang Leping Chen Xueliang Yuan Guifang Chen 《Chinese Journal of Population,Resources and Environment》 2023年第4期231-238,共8页
Although the tobacco industry is a significant contributor to energy consumption and carbon emissions its negative environmental impact has received inadequate attention globally.Cigarette factories are a key link in ... Although the tobacco industry is a significant contributor to energy consumption and carbon emissions its negative environmental impact has received inadequate attention globally.Cigarette factories are a key link in the tobacco industry’s production chain,and using data provided by a cigarette factory in China we conduct a life cycle assessment to account for the carbon footprint of cigar production in cigarette factories.The results of the assessment show that factory air conditioning is the most important contributor to the environmental load of the cigar manufacturing process,while electricity is the key factor that contributes the greatest envi‐ronmental load across all of the processes in the product life cycle.In addition,packaging,including small boxes and cigarette cartons,has a significant impact on the industry’s environmental footprint due to its use of raw materials.We find the carbon footprint of the entire production process for cigar products to be 383.59 kg CO_(2) eq.Based on our findings,we suggest ways to optimize cigar/cigarette factory processes to re‐duce carbon emissions that can help to promote sustainable development in related industries. 展开更多
关键词 cigar process Life cycle assessment Carbon emissions Environmental impact
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距离Cigar域与拟共形映射
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作者 孙胜先 褚玉明 黄曼子 《数学研究》 CSCD 2007年第4期392-395,共4页
设f:Rn→Rn是一同胚,本文证明了f是拟共形映射的充要条件是f将Rn中的任一距离Cigar域映成Rn中的距离Cigar域.
关键词 拟共形映射 同胚 距离cigar
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The Function of Cigar in Blackmail
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作者 周莉 黄哲 《海外英语》 2012年第9X期240-243,共4页
This thesis intends to use the symbolic structure of cigar to analyze the extract Blackmail from Arthur Hailey's short novel Hotel.The function of cigar in Blackmail can be concluded as a) constructive clue of the... This thesis intends to use the symbolic structure of cigar to analyze the extract Blackmail from Arthur Hailey's short novel Hotel.The function of cigar in Blackmail can be concluded as a) constructive clue of the plot progression,b) genteel carrier in making up characters.Rotating around the constructive clue,cigar,the writer of this thesis breaks down the whole story into seven parts,i.e.mystical entrance,prelude,crossfire,preparatory victory,absolute superiority,negotiation (absence of cigar) and discard.As to cigar's function of making up character,this thesis examines it from four main social and historical aspects,i.e.the origin of cigar in history,the social token of cigar,the complicated approaches of using cigar,and the historical stereotypes related to cigar smoking. 展开更多
关键词 FUNCTION of cigar SYMBOLIC structure CONSTRUCTIVE
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Exclusive cigar smoking in the United States and smoking-related diseases: A systematic review
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作者 Peter N Lee Janette S Hamling Alison J Thornton 《World Journal of Meta-Analysis》 2020年第3期245-264,共20页
BACKGROUND Little information has been published on the risks of cigar smoking.Since 1990 cigar smoking has become more prevalent in the United States.AIM To summarise the evidence from the United States relating excl... BACKGROUND Little information has been published on the risks of cigar smoking.Since 1990 cigar smoking has become more prevalent in the United States.AIM To summarise the evidence from the United States relating exclusive cigar smoking to risk of the major smoking-related diseases.METHODS Literature searches detected studies carried out in the United States which estimated the risk of lung cancer,chronic obstructive pulmonary disease(COPD),heart disease,stroke or overall circulatory disease in exclusive cigar smokers as compared to those who had never smoked any tobacco product.Papers were identified from reviews and detailed searches on MEDLINE.For each study,data were extracted onto a study database and a linked relative risk database.Relative risks and 95%CIs were extracted,or estimated,relating to current,former or ever exclusive cigar smokers,and meta-analysed using standard methods.Sensitivity analyses were conducted including or excluding results from studies that did not quite fit the full selection criteria(for example,a paper presenting combined results from five studies,where 86%of the population were in the United States).RESULTS The literature searches identified 17 relevant publications for lung cancer,four for COPD and 12 for heart disease,stroke and circulatory disease.These related to 11 studies for lung cancer,to four studies for COPD and to eight studies for heart disease,stroke or overall circulatory disease.As some studies provided results for more than one disease,the total number of studies considered was 13,with results from four of these used in sensitivity analyses.There was evidence of significant heterogeneity in some of the meta-analyses so the random-effects estimates are summarized below.As the results from the sensitivity analyses were generally very similar to those from the main analyses,and involved more data,only the sensitivity results are summarized below.For lung cancer,relative risks(95%CI)for current,former and ever smokers were respectively,2.98(2.08 to 4.26),1.61(1.23 to 2.09),and 2.22(1.79 to 2.74)based on 6,4 and 10 individual study estimates.For COPD,the corresponding estimates were 1.44(1.16 to 1.77),0.47(0.02 to 9.88),and 0.86(0.48 to 1.54)based on 4,2 and 2 estimates.For ischaemic heart disease(IHD)the estimates were 1.11(1.04 to 1.19),1.26(1.03 to 1.53)and 1.15(1.08 to 1.23)based on 6,3 and 4 estimates,while for stroke they were 1.02(0.92 to 1.13),1.08(0.85 to 1.38),and 1.11(0.95 to 1.31)based on 5,3 and 4 estimates.For overall circulatory disease they were 1.10(1.05 to 1.16),1.11(0.84 to 1.46),and 1.15(1.06 to 1.26)based on 3,3 and 4 estimates.CONCLUSION Exclusive cigar smoking is associated with an increased risk of lung cancer,and less so with COPD and IHD.The increases are lower than for cigarettes. 展开更多
关键词 Tobacco products cigar smoking Lung neoplasms Pulmonary disease Chronic obstructive Heart diseases STROKE Circulatory disease Systematic review Metaanalysis
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拟共形映射和弱Cigar域 被引量:1
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作者 褚玉明 黄曼子 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2007年第3期659-663,共5页
设f是R^n到R^n上的同胚,本文证明了f是拟共形映射的充要条件是f将R^n中的任一弱Cigar域映成R^n中的弱Cigar域。
关键词 拟共形映射 cigar 弱拟凸域
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莫海威芽孢杆菌(Bacillus mojavensis)ZLX10对发酵雪茄烟叶中性致香成分的影响
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作者 赵晓超 李林林 +8 位作者 施友志 张贝贝 周亚彬 禹言 张静亚 瞿欢 普倩 黄友谊 潘勇 《湖北农业科学》 2024年第6期173-180,186,共9页
为探究烟草源微生物单菌发酵对雪茄烟叶挥发性致香成分的影响,采用GC-MS检测莫海威芽孢杆菌(Bacillus mojavensis)ZLX10发酵雪茄烟叶中性致香成分,筛选差异致香成分,并与感官评价进行相关性分析,结合ROAV值变化,明确ZLX10提升雪茄烟叶... 为探究烟草源微生物单菌发酵对雪茄烟叶挥发性致香成分的影响,采用GC-MS检测莫海威芽孢杆菌(Bacillus mojavensis)ZLX10发酵雪茄烟叶中性致香成分,筛选差异致香成分,并与感官评价进行相关性分析,结合ROAV值变化,明确ZLX10提升雪茄烟叶感官品质的关键致香成分。结果表明,ZLX10发酵雪茄烟叶后,香气总量和大多数中性致香成分含量均显著提高,共筛选得到15种差异中性致香成分,共有10种致香成分显著上调(P<0.05),其中巨豆三烯酮A、巨豆三烯酮B、6-甲基-5-庚烯-2-酮、2,6,6-三甲基-2-环己烯-1,4-二酮、茄酮和植物醇与烟叶香气呈显著正相关(P<0.05),可认为是增加烟叶干香和花香的关键差异致香成分;共有5种致香成分显著下调(P<0.05),其中苯乙醛和2,4-二叔丁基-6-硝基苯酚与烟叶刺激性呈显著正相关(P<0.05),对烟叶香气有较大的负面影响。由此可知,ZLX10发酵能促进雪茄烟叶香气质和香气量得到提升,这为人工接菌发酵雪茄烟叶提供了基础。 展开更多
关键词 雪茄烟叶 莫海威芽孢杆菌 烟叶发酵 中性致香成分
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雪茄烟新品种雪雅香1号的选育及特征特性
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作者 刘国祥 李媛 +8 位作者 戴培刚 王剑 霍光 刘好宝 籍燕 陈志强 潘勇 杨爱国 张兴伟 《中国烟草学报》 CAS CSCD 北大核心 2024年第1期129-134,共6页
【目的】选育适合国内种植的优质抗病雪茄烟茄衣新品种。【方法】以优质雪茄烟品种M6的雄性不育系(MSM6)为母本,抗病性强且产量较高的J20为父本,杂交选育了雄性不育一代杂交种雪雅香1号。【结果】该品种田间生长势强,生长整齐一致;抗病... 【目的】选育适合国内种植的优质抗病雪茄烟茄衣新品种。【方法】以优质雪茄烟品种M6的雄性不育系(MSM6)为母本,抗病性强且产量较高的J20为父本,杂交选育了雄性不育一代杂交种雪雅香1号。【结果】该品种田间生长势强,生长整齐一致;抗病性表现较好,对烟草普通花叶病毒病(Tobacco mosaic virus, TMV)免疫,中抗黑胫病,中抗~抗青枯病,抗根黑腐病;烟叶主要经济性状表现较好,化学成分比例较协调,外观质量、物理特性符合优质茄衣的要求;雪茄烟风格较显著,香气量和香气质的表现较好。【结论】雪雅香1号是我国自主选育的雪茄烟新品种,能够兼顾品质、经济和抗病性,烟叶质量可以满足中式茄衣的需求,适宜在四川烟区、湖北烟区及国内其他同类烟区种植。 展开更多
关键词 雪茄烟 品种 雪雅香1号 选育 特征特性
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夏冬两季发酵雪茄烟叶的代谢组差异分析
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作者 虞昕磊 何结望 +6 位作者 林国平 李金海 王大爱 袁跃斌 刘圣高 李志豪 陶德欣 《生物技术通报》 CAS CSCD 北大核心 2024年第6期260-270,共11页
【目的】解析夏冬季节发酵的雪茄烟叶代谢物差异。【方法】采用超高效液相色谱串联质谱(UPLC-MS/MS)技术对发酵前、冬季发酵、夏季发酵的雪茄烟叶样品进行广泛靶向代谢物检测。【结果】发酵期间(历时34 d)夏季、冬季发酵房平均温度分别... 【目的】解析夏冬季节发酵的雪茄烟叶代谢物差异。【方法】采用超高效液相色谱串联质谱(UPLC-MS/MS)技术对发酵前、冬季发酵、夏季发酵的雪茄烟叶样品进行广泛靶向代谢物检测。【结果】发酵期间(历时34 d)夏季、冬季发酵房平均温度分别是27.2℃、14.7℃,二者相差12.5℃,平均湿度分别是77.6%、66.7%,二者相差10.9%,夏季更符合烟叶发酵相对高温、高湿的环境要求;雪茄烟叶样品检测得到905种代谢物包含10类:生物碱、酚酸、黄酮、脂质、氨基酸、有机酸、萜类、糖类、核苷酸、木质素,其中生物碱、有机酸、脂质含量比例居前三,分别是24.5%、23.7%、15.0%。烟叶发酵后,有机酸、脂质、氨基酸、酚酸的含量都显著提升,生物碱、萜类、黄酮、糖类、木质素的含量有不同程度的减少。夏季发酵的烟叶生物碱、萜类代谢转化更剧烈,有机酸、氨基酸、黄酮、脂质、糖类含量较高,化学成分更协调,香气质量更丰富,烟气柔顺、余味甜润,感官品质更优。【结论】鄂西南地区夏季自然高温高湿环境,更顺应雪茄烟农业发酵理想状态,将当年生产的雪茄烟叶在冬季自然醇化后推迟到次年夏季发酵,或可作为探索推动雪茄烟发酵工序提质增效的参考方案。 展开更多
关键词 雪茄烟叶 发酵 代谢组学 感官质量 差异分析
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雪茄茄芯和茄衣烟叶不同区段化学成分和品质差异性分析
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作者 李晶晶 荣仕宾 +7 位作者 秦艳青 周骏 曾代龙 钟秋 赵园园 刘德水 张瑞娜 史宏志 《河南农业科学》 北大核心 2024年第1期62-69,共8页
为明确雪茄烟叶不同区段的品质差异,以雪茄品种德雪1号发酵后分拣出的一等茄衣和茄芯烟叶为材料,对叶基至叶尖5个不同区段的常规化学成分、中性香气成分、烟草特有亚硝胺(TSNAs)及前体物含量进行测定,并进行感官评吸鉴定。结果表明,雪... 为明确雪茄烟叶不同区段的品质差异,以雪茄品种德雪1号发酵后分拣出的一等茄衣和茄芯烟叶为材料,对叶基至叶尖5个不同区段的常规化学成分、中性香气成分、烟草特有亚硝胺(TSNAs)及前体物含量进行测定,并进行感官评吸鉴定。结果表明,雪茄烟叶不同区段化学成分差异显著,还原糖、总糖含量在叶尖和近叶尖区段相对较高,总氮和蛋白质含量在近叶基区段较高,烟碱含量自叶基到叶尖先升高后降低。茄芯、茄衣烟叶的中性香气成分含量从叶基至叶尖均先增加后减少,其中茄芯烟叶在叶中区段最高,茄衣在近叶基区段最高。2种类型雪茄烟叶的TSNAs含量从叶基至叶尖均持续下降,但降幅不同,茄芯、茄衣烟叶叶尖较叶基分别下降68.25%、30.19%。除刺激性外,2种烟叶的6项感官质量指标得分及总分从叶基至叶尖均表现为先升高后降低,以叶中和近叶尖区段较优。综上,雪茄烟叶以叶中和近叶尖区段香气浓郁,有害成分低,评吸质量较好。 展开更多
关键词 雪茄 茄芯 茄衣 烟叶 不同区段 化学成分 中性致香成分 烟草特有亚硝胺
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雪茄烟发酵过程微生物群落结构及物种均衡性变化特征
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作者 陈燕 张光海 +8 位作者 朱宣全 王戈 姚恒 夏华昌 孔光辉 王娜 周鹏 杜宇 白羽祥 《中国烟草科学》 CSCD 北大核心 2024年第1期87-95,共9页
为明确雪茄烟叶发酵过程中微生物群落组成、结构及物种均衡性的变化特征,基于高通量测序技术,采用细菌、真菌多样性指数比值分析方法,对不同发酵阶段雪茄烟叶表面细菌、真菌进行分析。结果表明,随发酵进行,细菌α多样性先升高后降低,在P... 为明确雪茄烟叶发酵过程中微生物群落组成、结构及物种均衡性的变化特征,基于高通量测序技术,采用细菌、真菌多样性指数比值分析方法,对不同发酵阶段雪茄烟叶表面细菌、真菌进行分析。结果表明,随发酵进行,细菌α多样性先升高后降低,在PEF3(中期)达到最高值;真菌α多样性基本稳定,仅在发酵PEF4(后期)显著降低;物种均衡性在前中期小幅度升高,但在PEF4后显著降低。PCoA分析显示,未发酵与发酵前中期细菌群落结构相似,与发酵后期明显分离。在发酵过程中,细菌葡萄球菌属(Staphylococcus)、假单胞菌属(Pseudomonas)和真菌明梭孢属(Monographella)、曲霉菌属(Aspergillus)、青霉菌属(Penicillium)为主要优势菌属。影响物种均衡性的关键微生物群落变化规律是:由发酵初期的泛生菌属(Pantoea)、甲基杆菌属(Methylobacterium)、鞘氨醇单胞菌属(Sphingomonas),变为发酵中期马赛菌属(Massilia)、壤霉菌属(Agromyces)、根瘤菌科(Rhizobiaceae),最后稳定为Staphylococcus、Pseudomonas、Trichomonascus、雷尔氏菌属(Ralstonia)、Monographella。将微生物分为两个模块研究,共筛选出8个有利于提高物种均衡性的关键菌属。最终结构方程模型表明,在雪茄烟叶发酵过程中,影响物种均衡性改变的主要环境因子是温度和湿度,二者通过影响关键菌属的丰度而影响物种均衡性。 展开更多
关键词 雪茄烟叶 发酵 微生物群落 物种均衡性
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雪茄烟叶蛋白提取及其水解产物的氨基酸组成和抗氧化活性
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作者 王贤贤 申国明 +3 位作者 刘新民 杜咏梅 高加明 高林 《云南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期76-83,共8页
【目的】研究雪茄烟叶蛋白提取及其水解产物的氨基酸组成和抗氧化活性,为烟叶蛋白资源的深度开发与利用提供理论依据和技术支撑。【方法】利用碱溶酸沉法提取雪茄烟叶蛋白,确定最佳提取条件;利用胃蛋白酶、复合蛋白酶、碱性蛋白酶、木... 【目的】研究雪茄烟叶蛋白提取及其水解产物的氨基酸组成和抗氧化活性,为烟叶蛋白资源的深度开发与利用提供理论依据和技术支撑。【方法】利用碱溶酸沉法提取雪茄烟叶蛋白,确定最佳提取条件;利用胃蛋白酶、复合蛋白酶、碱性蛋白酶、木瓜蛋白酶和中性蛋白酶对提取的蛋白进行水解,并对水解产物的氨基酸组成和抗氧化活性进行分析。【结果】雪茄烟叶蛋白的最佳提取条件为:料液比1∶25(g∶mL)、碱溶pH为8.0、碱溶时间80 min、提取温度60℃、酸沉pH为3.0,最佳提取率为79.08%。雪茄烟叶蛋白通过胃蛋白酶水解的效果最好,水解度为15.52%;其水解产物中游离氨基酸含量最高,必需氨基酸、疏水性氨基酸、负电荷氨基酸和正电荷氨基酸的含量也高于其他酶解产物,必需氨基酸与总氨基酸的比值、必需氨基酸与非必需氨基酸的比值均高于FAO/WHO标准规定值。随着水解时间的延长,水解产物对超氧阴离子自由基、DPPH自由基和羟自由基的清除能力呈上升趋势,且对超氧阴离子自由基的清除率最高(57.54%)。【结论】碱溶酸沉法能够较好地提取雪茄烟叶蛋白;通过胃蛋白酶水解雪茄烟叶蛋白,其氨基酸组成和比例得到改善,提升了营养价值,增强了其水解产物的抗氧化能力。 展开更多
关键词 雪茄烟 烟叶蛋白 酶解 氨基酸 抗氧化活性
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海南典型产区晾制后雪茄烟叶代谢组的差异分析
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作者 杨鸿宇 耿召良 +7 位作者 颜统晶 秦艳青 李爱军 谢良文 耿宗泽 宋世旭 宋朝鹏 蔡斌 《中国烟草学报》 CAS CSCD 北大核心 2024年第3期95-104,共10页
【目的】研究茄芯品种“海研201”在海南两个典型产区晾制后烟叶质量差异的物质基础。【方法】基于高效液相色谱串联质谱(HPLC-MS/MS)非靶向代谢组学方法,分析茄芯品种“海研201”在五指山番阳和儋州光村两个典型产区晾制后雪茄烟叶中... 【目的】研究茄芯品种“海研201”在海南两个典型产区晾制后烟叶质量差异的物质基础。【方法】基于高效液相色谱串联质谱(HPLC-MS/MS)非靶向代谢组学方法,分析茄芯品种“海研201”在五指山番阳和儋州光村两个典型产区晾制后雪茄烟叶中代谢产物及通路的差异。【结果】(1)海南5个主产烟区可分为2类,五指山番阳、昌江海尾和白沙荣邦产区为一类,儋州光村与东方大田产区为一类。(2)五指山番阳和儋州光村两个典型产区晾制后的雪茄烟叶中共鉴定到222种代谢物的相对含量存在显著差异;(3)KEGG数据库注释及富集结果显示,五指山番阳和儋州光村两个典型产区晾制后雪茄烟叶的差异代谢物主要富集在氨基酸的生物合成途径、代谢途径以及精氨酸的生物合成途径。氨基酸的生物合成途径差异最显著,其中富集到的L-酵母氨酸、L-缬氨酸、L-谷氨酰胺、L-瓜氨酸、S-腺苷蛋氨酸、N-乙酰-DL-谷氨酸在儋州光村产区晾制后雪茄烟叶中的相对含量均显著低于五指山番阳产区;(4)感官质量评价显示,儋州光村产区晾制后的雪茄烟叶在香气丰富度、杂气、品质特征等方面均优于五指山番阳产区。【结论】两个典型产区晾制后雪茄烟叶的代谢谱存在显著差异,特别是晾制后烟叶的部分游离氨基酸及其衍生物含量,可能与两个产区烟叶品质有一定关系。本研究结果将为雪茄原料的后续技术改进和特色彰显提供理论支撑。 展开更多
关键词 雪茄晾制 代谢组学 产区差异 氨基酸生物合成
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基于模糊聚类的沂水雪茄烟种植生态适应性评价
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作者 孙飞虎 柳平增 +3 位作者 孟宪勇 陈秀斋 张超 刘莉 《中国农机化学报》 北大核心 2024年第6期330-336,共7页
通过生态适应性评价筛选适合雪茄烟种植生产的区域,是提升雪茄原料产量与质量、促进雪茄产业发展的前提。以山东沂水雪茄庄园为例,运用生育期平均气温、昼夜气温差、生育期≥10℃活动积温、生育期相对湿度、生育期降雨量以及生育期日均... 通过生态适应性评价筛选适合雪茄烟种植生产的区域,是提升雪茄原料产量与质量、促进雪茄产业发展的前提。以山东沂水雪茄庄园为例,运用生育期平均气温、昼夜气温差、生育期≥10℃活动积温、生育期相对湿度、生育期降雨量以及生育期日均日照时数等雪茄种植生产的重要气候指标,对哈瓦那、比那尔得里奥、什邡等11个国内外优质雪茄烟区进行模糊聚类并通过隶属度函数求得各地区相应的CFI值。模糊聚类结果表明,可将11个区域划分为4类,其中沂水气候条件与哈瓦那、比那尔得里奥、什邡、多米尼加、巴伊亚州等国内外优质雪茄种植地区相似,它们的气候适宜性指数CFI值依次为沂水(0.931)、哈瓦那(0.963)、比那尔德里奥(0.956)、什邡(0.944)、多米尼加(0.932)、巴伊亚州(0.892),尤其沂水与多米尼加的CFI指数最为相近。由此得出,沂水雪茄庄园具有种植优质雪茄烟的生态气候条件。 展开更多
关键词 模糊聚类 雪茄 气候适宜性 生态适应性 隶属度函数
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雪茄烟叶工业发酵过程中霉变对真菌群落结构的影响研究
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作者 黄阔 朱贝贝 +5 位作者 叶长文 邹梦影 李栋 李东亮 李青常 薛芳 《轻工学报》 CAS 北大核心 2024年第1期73-78,96,共7页
为探究雪茄烟叶工业发酵过程中真菌群落结构随霉变发生的变化情况,以德雪一号雪茄烟叶为实验材料,采用微生物学计数方法和Illumina MiSeq高通量测序技术对雪茄烟叶工业发酵过程中正常烟叶和霉变烟叶进行霉菌数量及真菌群落结构变化分析... 为探究雪茄烟叶工业发酵过程中真菌群落结构随霉变发生的变化情况,以德雪一号雪茄烟叶为实验材料,采用微生物学计数方法和Illumina MiSeq高通量测序技术对雪茄烟叶工业发酵过程中正常烟叶和霉变烟叶进行霉菌数量及真菌群落结构变化分析。结果表明:与正常烟叶相比,发酵第30 d霉变雪茄烟叶中,霉菌数量最高(8.3×10^(4) CFU/g),物种丰富度和多样性最低,OTU数量最少;在门水平上,子囊菌门(Ascomycota)在发酵第30 d霉变烟叶中为绝对优势菌门,平均相对丰度为99.82%;在属水平上,曲霉属(Aspergillus)为整个发酵过程中的主要优势菌属,在发酵第30 d霉变雪茄烟叶中平均相对丰度最大(92.32%);发酵第30 d霉变雪茄烟叶与正常烟叶相比在物种组成上具有明显差别,其中曲霉属既是优势菌属,又是组间差异菌属,且在各样品中平均相对丰度均最高,推断其为引起雪茄霉变发生的关键菌属。 展开更多
关键词 雪茄烟叶 工业发酵 真菌 霉变 群落结构
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1株具有蛋白降解能力的雪茄优势菌株鉴定与培养条件优化
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作者 李林林 王剑 +5 位作者 张贝贝 周亚彬 刘佳琪 黄友谊 王荣浩 潘勇 《贵州农业科学》 CAS 2024年第2期70-76,共7页
【目的】探明雪茄烟发酵所需优势菌株的最佳培养基配方和最优培养条件,为雪茄烟叶人工接种发酵提供菌种来源和菌株规模制备提供科学依据。【方法】从雪茄烟叶中分离出1株具有蛋白降解能力的优势菌株GL2,通过16S rDNA序列比对和生理生化... 【目的】探明雪茄烟发酵所需优势菌株的最佳培养基配方和最优培养条件,为雪茄烟叶人工接种发酵提供菌种来源和菌株规模制备提供科学依据。【方法】从雪茄烟叶中分离出1株具有蛋白降解能力的优势菌株GL2,通过16S rDNA序列比对和生理生化特性进行鉴定,并通过单因素试验和正交试验优化培养基配方和培养条件。【结果】菌株GL2为沙福芽孢杆菌(Bacillus safensis),最佳培养基配方为牛肉膏10 g/L、酵母提取物35 g/L、MgSO_(4)0.25 g/L;最适培养条件为接种量2%(v/v)、装液量30 m L/250m L、种龄16 h。菌株GL2在最佳培养基配方和最适培养条件下培养24 h后,生物量达1.153×10^(10)CFU/m L,是优化前的4400倍。【结论】优化后培养基成分和培养条件能促进沙福芽孢杆菌(Bacillus safensis)菌株GL2的生长,有利于该菌株大规模制备与应用。 展开更多
关键词 雪茄 优势菌株 菌株鉴定 沙福芽孢杆菌 培养条件优化 生物量
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^(60)Co-γ射线辐照对雪茄烟叶发酵微生物和代谢物变化及烟叶质量的影响
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作者 张蓝月 秦艳青 +3 位作者 赵园园 任梦娟 张瑞娜 史宏志 《中国烟草学报》 CAS CSCD 北大核心 2024年第2期125-134,共10页
【目的】通过^(60)Co-γ射线辐照灭菌,明确微生物在雪茄烟叶发酵过程中的重要作用。【方法】以四川雪茄烟品种德雪1号为试验材料,以剂量10 kGy的^(60)Co-γ射线对发酵前烟叶进行辐照处理,测定分析发酵过程中烟叶微生物多样性、代谢组学... 【目的】通过^(60)Co-γ射线辐照灭菌,明确微生物在雪茄烟叶发酵过程中的重要作用。【方法】以四川雪茄烟品种德雪1号为试验材料,以剂量10 kGy的^(60)Co-γ射线对发酵前烟叶进行辐照处理,测定分析发酵过程中烟叶微生物多样性、代谢组学、中性香气成分和常规化学成分含量。【结果】(1)辐照组烟叶发酵28 d样本经传统分离培养和Illumina MiSeq高通量测序均未发现细菌群落。(2)非靶向代谢组学结果显示,辐照组烟叶发酵28 d后芸香苷、根皮苷和山奈酚等多酚类物质,山奈酚-3-O-芸香糖苷等多酚糖苷类物质,二肽等含量高于未辐照组烟叶,而亮氨酸、L-丝氨酸和脯氨酸等氨基酸含量低于未辐照烟叶。KEGG富集差异显著的代谢通路是黄酮和黄酮醇生物合成通路与花生四烯酸代谢通路。(3)发酵28 d后,两组烟叶的生物碱、还原糖、总糖、淀粉和蛋白质含量均显著降低,辐照组烟叶发酵前后各指标的降幅小于未辐照烟叶。辐照组烟叶发酵28 d后中性香气成分总量显著低于未辐照烟叶,而棕色化反应产物总量显著增加,烟叶劲头、杂气、刺激性更大。【结论】对发酵前烟叶进行10 kGy^(60)Co-γ射线辐照可有效杀灭烟叶细菌,发酵28 d后大分子物质降解转化低于未辐照烟叶,感官质量增加幅度减小,但相比于发酵前仍有一定程度的改善。 展开更多
关键词 雪茄烟叶 ^(60)Co-γ射线 发酵 微生物 代谢组学 烟叶质量
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遮阴栽培对雪茄茄衣烟叶叶面均匀性的影响
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作者 郭昊 谭荣雷 +8 位作者 杨锦鹏 余君 黄文昌 杨久红 乔保明 杨瑞玮 徐芳森 杨春雷 丁广大 《中国农业科技导报》 CAS CSCD 北大核心 2024年第2期216-225,共10页
为探究遮阴栽培对雪茄茄衣品种叶面均匀性的影响,以雪茄茄衣品种‘楚雪26号’(CX-26)为研究对象,在大田试验条件下进行不同程度的遮阴处理,分析其成熟期上部叶和中部叶的叶面厚度、叶面平展度、叶片密度、主支脉粗细、主支脉占叶片干物... 为探究遮阴栽培对雪茄茄衣品种叶面均匀性的影响,以雪茄茄衣品种‘楚雪26号’(CX-26)为研究对象,在大田试验条件下进行不同程度的遮阴处理,分析其成熟期上部叶和中部叶的叶面厚度、叶面平展度、叶片密度、主支脉粗细、主支脉占叶片干物质量比例以及SPAD值等的差异。结果表明,随着遮阴程度的增加,上部叶的叶面厚度、叶片密度以及叶片SPAD值均逐渐下降;当透光率为70%时,叶面厚度、叶片密度与不遮阴处理相比分别下降35.5%和33.3%,而中部叶中各性状则逐渐上升。遮阴栽培显著增加上部叶的叶面平展度,但降低了中部叶的叶面平展度;在透光率为70%时,上部叶的叶面平展度达到最大,为0.98;遮阴栽培增加上部叶主支脉占叶片干物质量比例,对中部叶主支脉占叶片干物质量比例的影响随遮阴程度的增加呈下降趋势,但差异不显著。遮阴栽培对中部叶主支脉的粗细程度无影响,但使上部叶的主支脉变细。以上研究结果为国产雪茄茄衣烟叶遮阴栽培技术提供理论基础。 展开更多
关键词 雪茄烟 遮阴栽培 透光率 叶面均匀性
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