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Industrial Biosystems Engineering and Biorefinery Systems
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作者 Shulin Chen 《生物工程学报》 CAS CSCD 北大核心 2008年第6期940-945,共6页
The concept of Industrial Biosystems Engineering (IBsE) was suggested as a new engineering branch to be developed for meeting the needs for science, technology and professionals by the upcoming bioeconomy. With emphas... The concept of Industrial Biosystems Engineering (IBsE) was suggested as a new engineering branch to be developed for meeting the needs for science, technology and professionals by the upcoming bioeconomy. With emphasis on systems, IBsE builds upon the interfaces between systems biology, bioprocessing, and systems engineering. This paper discussed the background, the suggested definition, the theoretical framework and methodologies of this new discipline as well as its challenges and future development. 展开更多
关键词 生物工程 生物系统 生物技术 发展现状
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Emerging multifaceted roles of the microbiome in cancer susceptibility
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作者 Hang Chang Jesus Perez-Losada Jian-Hua Mao 《World Journal of Clinical Oncology》 2025年第9期92-105,共14页
Identifying the factors that contribute to individual susceptibility to cancer is essential for both prevention and treatment.The advancement of biotechnologies,particularly next-generation sequencing,has accelerated ... Identifying the factors that contribute to individual susceptibility to cancer is essential for both prevention and treatment.The advancement of biotechnologies,particularly next-generation sequencing,has accelerated the discovery of genetic variants linked to cancer susceptibility.While hundreds of cancer-susceptibility genes have been identified,they only explain a small fraction of the overall cancer risk,a phenomenon known as"missing heritability".Despite progress,even considering factors such as epistasis,epigenetics,and gene-environment interactions,the missing heritability remains unresolved.Recent research has revealed that an individual's microbiome composition plays a significant role in cancer susceptibility through several mechanisms,such as modulating immune cell activity and influencing the presence or removal of environmental carcinogens.In this review,we examine the multifaceted roles of the microbiome in cancer risk and explore gene-microbiome and environment-microbiome interactions that may contribute to cancer susceptibility.Additionally,we highlight the importance of experimental models,such as collaborative cross mice,and advanced analytical tools,like artificial intelligence,in identifying microbial factors associated with cancer risk.Understanding these microbial determinants can open new avenues for interventions aimed at reducing cancer risk and guide the development of more effective cancer treatments. 展开更多
关键词 Cancer susceptibility Genetic variants Genome-wide association study Missing heritability MICROBIOME Microbiome-wide association study
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Association Between Long-Term PM1 Exposure and Cognitionin Middle-Aged and Older Adults:Evidence from China and the United Kingdom
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作者 Qiurun Yu Hongcheng Wei +7 位作者 Mingzhi Zhang Xiaochen Zhang Francis Manyori Bigambo Danrong Chen Quanquan Guan Bo Hang Antoine M.Snijders Yankai Xia 《Engineering》 2025年第10期223-230,共8页
Early risk detection and management are essential for cognitive preservation.While particulate matter with a diameter smaller than 2.5μm(PM_(2.5))is considered harmful to cognition,the effect of smaller,more penetrat... Early risk detection and management are essential for cognitive preservation.While particulate matter with a diameter smaller than 2.5μm(PM_(2.5))is considered harmful to cognition,the effect of smaller,more penetrative particulate matter with a diameter smaller than 1μm(PM_(1))requires further evidence and explicit safety thresholds.In this study,we explored the effects of long-term PM_(1) exposure on early cognitive impairment and longitudinal cognitive changes in middle-aged and older populations.This study assessed data from two large-scale longitudinal surveys:the China Health and Retirement Longitudinal Study(CHARLS)and UK Biobank(UKB).Cross-sectional,longitudinal,and trajectory analyses were conducted to investigate the association between long-term PM_(1) exposure and cognition.Additionally,the expo sure-response curves were fitted to determine the customized thresholds.The findings indicated that sustained PM_(1) exposure may lead to mild cognitive impairment,particularly at concentrations exceeding 30 and 5.6μg·m^(-3) in CHARLS and UKB participants,respectively.Furthermore,we found that long-term PM_(1) exposure can contribute to rapid cognitive decline at concentrations exceeding 23 and 5.5μg·m^(-3) in CHARLS and UKB participants,respectively.In conclusion,reducing PM_(1) exposure can improve the cognitive health of middle-aged and older adults. 展开更多
关键词 PM_(1) COGNITION Mild cognitiveimpairment Rapid cognitivedecline Longitudinal study Multi-regional study
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Advances in humins formation mechanism,inhibition strategies,and value-added applications
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作者 Yitong Wang Chaofeng Zhang +7 位作者 Cheng Cai Caoxing Huang Xiaojun Shen Hongming Lou Changwei Hu Xuejun Pan Feng Wang Jun Xie 《Chinese Journal of Catalysis》 2025年第4期25-53,共29页
Humins,as a group of by-products formed through the condensation and coupling of fragment intermediates during lignocellulosic biomass refining,can cause numerous negative effects such as the wastage of carbon resourc... Humins,as a group of by-products formed through the condensation and coupling of fragment intermediates during lignocellulosic biomass refining,can cause numerous negative effects such as the wastage of carbon resources,clogging of reactor piping,deactivation of catalyst,and barriers to product separation.Elucidating the generation mechanism of humins,developing efficient inhibitors,and even utilizing them as a resource,both from the perspective of atom economy and safe production,constitutes a research endeavor replete with challenges and opportunities.Orbiting the critical issue of humins structure and its generation mechanism from cellulose and hemicellulose resources,the random condensation between intermediates such as 5-hydroxymethylfurfural,furfural,2,5-dioxo-6-hydroxyhexanal,and 1,2,4-benzenetriol etc.were systematically summarized.Additionally,the presence of lignin in real biorefining processes further promotes the formation of a special type of humins known as"pseudo-lignin".The influences of various factors,including raw materials,reaction temperature and time,acid-base environment,as well as solvent systems and catalysts,on the formation of humins were comprehensively analyzed.To minimize the formation of humins,the design of efficient solvent systems and catalysts is crucial.Furthermore,this review investigates the approaches to value-added applications of humins.The corresponding summary could provide guidance for the development of the humins chemistry. 展开更多
关键词 Humins LIGNOCELLULOSIC Biomass refining Biomass conversion Pseudo-lignin
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采后热风与热水处理杀虫的水果温度场有限元模拟 被引量:9
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作者 黄智 严荣军 +3 位作者 李瑞 朱瀚昆 令博 王绍金 《农业工程学报》 EI CAS CSCD 北大核心 2014年第2期252-259,共8页
热风和热水加热具有高效、环保且易于控制的优点,是一种替代化学熏蒸控制采后水果虫害的有效物理方法。但由于缺乏对加热速率、加热时间与温度分布等问题的深入与系统研究,常导致杀虫效果较差或对水果品质造成一定负面影响。为了研究水... 热风和热水加热具有高效、环保且易于控制的优点,是一种替代化学熏蒸控制采后水果虫害的有效物理方法。但由于缺乏对加热速率、加热时间与温度分布等问题的深入与系统研究,常导致杀虫效果较差或对水果品质造成一定负面影响。为了研究水果采后热处理过程的传热机理,建立了水果热处理时的非稳态传热模型,利用有限元分析软件COMSOL建模求解,并进行了试验验证。结果表明,模拟值与实测值之间的均方根误差均低于8%,从而验证了模拟的可靠性。达到相同的热处理效果,水果热水(55℃)加热时的热处理时间仅为热风(55℃)的30%,所以热水是一种更有效的加热介质。增加热风的流速可以提高加热速率,而热水循环速度对传热速率影响较小。水果内部的传热速率主要受水果大小、介质流动速度和水果形状的影响,热扩散系数对水果加热时间的影响较小。所建立的水果传热模型及相关试验结果可为水果采后热杀虫工艺参数的确定及优化提供参考。 展开更多
关键词 有限元分析 水果 虫害控制 热风 热水 加热速率 温度分布
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射频-热风与热风处理保鲜白面包的比较 被引量:31
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作者 刘嫣红 唐炬明 +2 位作者 毛志怀 MahJae-Hyung 王绍金 《农业工程学报》 EI CAS CSCD 北大核心 2009年第9期323-328,共6页
为将射频技术应用到袋装面包的保鲜处理中,以有效延长袋装面包的保存期,论文研究了射频-热风处理对于袋装面包的保鲜效果,并从灭菌效应、加热速率以及处理后面包的品质变化3方面与传统的热风处理方式作了对比。研究表明,与传统的热风处... 为将射频技术应用到袋装面包的保鲜处理中,以有效延长袋装面包的保存期,论文研究了射频-热风处理对于袋装面包的保鲜效果,并从灭菌效应、加热速率以及处理后面包的品质变化3方面与传统的热风处理方式作了对比。研究表明,与传统的热风处理相比,射频-热风处理可在更低的温度和更短的时间内获得满意的杀菌效果。对袋装切片面包进行射频-热风处理,其加热速率约为传统热风处理的30倍,并且可以更好地保持面包的品质,但其缺点是会引起面包表面积较大的收缩。 展开更多
关键词 热风加热 贮藏 食品 射频-热风处理 面包 保存期
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基于超宽带无线定位的农业设施内移动平台路径跟踪研究 被引量:26
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作者 姚立健 Santosh K Pitla +2 位作者 杨自栋 夏坡坡 赵辰彦 《农业工程学报》 EI CAS CSCD 北大核心 2019年第2期17-24,共8页
为实现农业设施内车辆自动导航,提出了一种基于超宽带(ultrawideband,UWB)无线定位的路径跟踪方法。运用4个基站组建UWB无线定位系统,采用加权最小二乘法(weighted least squares, WLS)法解超静定方程组,提高了移动标签的定位精度。重... 为实现农业设施内车辆自动导航,提出了一种基于超宽带(ultrawideband,UWB)无线定位的路径跟踪方法。运用4个基站组建UWB无线定位系统,采用加权最小二乘法(weighted least squares, WLS)法解超静定方程组,提高了移动标签的定位精度。重新定义前视距离,根据车体航向与前视直线的夹角界定车体偏差程度,并提出基于动态前视距离的改进型纯追踪模型。在MATLAB 2016a软件环境下的仿真说明该文算法优于采用固定视距的传统纯追踪算法,并进行实车试验。结果显示,在UWB定位系统的引导下,车体在不同初始状态下均能很好地收敛到期望直线,当速度为0.5 m/s时,在4种初始状态下进行直线跟踪,稳态偏差为5.4~8.4 cm,稳态偏差均值为6.3 cm。在矩形路径跟踪时,当横向偏差和航向偏差均为0的初始状态下,全程平均偏差为20.6 cm,跟踪偏差主要出现在90°转向处,最大偏差为85.5 cm,说明改进后的纯追踪算法的路径追踪质量均优于采用固定视距的传统纯追踪模型,能满足农业设施内移动平台自动导航的需求。该方法可为农业设施内车辆导航提供新思路。 展开更多
关键词 农业机械 控制 模型 超宽带 纯追踪 动态前视距离 路径跟踪
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芦笋机械化收获技术现状与发展分析 被引量:8
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作者 陈度 ZHANG Qin +1 位作者 王书茂 王新 《中国农业大学学报》 CAS CSCD 北大核心 2016年第4期113-120,共8页
针对现有芦笋机械收获技术的特点,将现有芦笋收获机分为集中式和选择式2大类,分别对2种类型收获机的收获原理、作业特点和工作效率进行详细分析,并指出集中式和选择式收获机各自存在的关键问题。在分析芦笋田间生长形态的基础上指出,三... 针对现有芦笋机械收获技术的特点,将现有芦笋收获机分为集中式和选择式2大类,分别对2种类型收获机的收获原理、作业特点和工作效率进行详细分析,并指出集中式和选择式收获机各自存在的关键问题。在分析芦笋田间生长形态的基础上指出,三维识别定位和机器人技术是最有可能成为解决芦笋高效收获的关键技术,将其应用于芦笋收获作业,并提高算法的实时识别效率,可以提高作物探测精度和分离收获效率,从而降低收获过程损失。通过与新型种植模式的集成,机器人收获技术必将解决芦笋机械化收获这一世界性难题。 展开更多
关键词 芦笋 收获机械 选择式收获 三维识别 移动机器人
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高光谱成像的猕猴桃货架期快速预测 被引量:15
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作者 邵园园 王永贤 +4 位作者 玄冠涛 高宗梅 刘艺 韩翔 胡志超 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2020年第6期1940-1946,共7页
货架期是影响果蔬品质和供应安全的重要因素,快速准确预测果蔬货架期已成为消费者、生产者和管理者共同关注的问题。猕猴桃含有多种有机物和氨基酸,具有丰富的营养价值,深受广大消费者的喜爱。但由于猕猴桃表面颜色变化不明显,人们仅凭... 货架期是影响果蔬品质和供应安全的重要因素,快速准确预测果蔬货架期已成为消费者、生产者和管理者共同关注的问题。猕猴桃含有多种有机物和氨基酸,具有丰富的营养价值,深受广大消费者的喜爱。但由于猕猴桃表面颜色变化不明显,人们仅凭感官难以准确判断猕猴桃的货架期和质量等级。采用高光谱成像结合化学计量学方法对不同储存条件下的保鲜猕猴桃进行了货架期预测。首先采集了4℃和(18±2)℃下保鲜时间为0,2,4天各120个猕猴桃样本在400~1000 nm的高光谱数据,测定其硬度值和可溶性固形物含量(SSC),获取猕猴桃切片高光谱图像。对猕猴桃平均光谱提取并进行Savitzky-Golay卷积平滑预处理后,通过光谱数据主成分分析(PCA),发现不同货架期和储存温度的猕猴桃样本在前2个主成分空间形成一定的聚类,4℃下猕猴桃样本出现少量重叠。为了减少波长变量,提高运算速度,使用载荷系数法(XL)与连续投影算法(SPA)选择特征波长。其中,4℃猕猴桃样本的XL和SPA特征波长分别7个(481,501,547,665,723,839,912 nm)和10个(406,428,520,617,665,682,723,818,878和983 nm);(18±2)℃猕猴桃样本XL特征波长为508,545,665,672,720,839和909 nm,SPA特征波长为575,622,731,756,779,800,828,865,920和983 nm。基于3∶1的光谱数据集划分三个货架期虚拟等级值1,2和3,以全光谱数据、特征波长为输入,建立非线性最小二乘支持向量机(LS-SVM)预测模型。结果表明,对于4℃下3种货架期猕猴桃样本,在全光谱和XL,SPA特征波长上的预测集准确度分别达到92.2%,92.2%,91.1%;(18±2)℃时预测准确度均为100%。猕猴桃切片图像PCA分析显示,除PC5中有部分噪声影响外,其他主成分图像均能完整反映猕猴桃切片信息,PC2图像可以明显呈现出猕猴桃切片在不同货架期的变化程度。进一步分析猕猴桃硬度和可溶性固形物含量发现,随着货架期延长,猕猴桃可溶性固形物含量逐渐增加,(18±2)℃时二者存在正相关性,相关系数为0.5576。硬度则随货架期延长逐渐减小,4和(18±2)℃下硬度值和货架期之间存在负相关性,相关系数分别为-0.3356和-0.5620。结合猕猴桃光谱信息,可以发现猕猴桃光谱反射率与其单个理化指标不成线性关系,而是多个指标的综合反映。因此,采用高光谱成像技术可以全面、准确、快速的预测猕猴桃货架期,为猕猴桃的生产、销售提供技术指导。 展开更多
关键词 猕猴桃 货架期 近红外高光谱技术 化学计量学
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黄原胶对马铃薯淀粉糊流变特性的影响 被引量:39
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作者 柴春祥 Sundaram Gunasekaran 《食品工业科技》 CAS CSCD 北大核心 2007年第8期115-118,共4页
对3%马铃薯淀粉,黄原胶含量为0.2%、0.4%和0.6%的淀粉糊流变特性进行了探讨。静态流变特性测定结果表明,在实验范围内,不同黄原胶含量的淀粉糊的流变模型为幂率模型,均为假塑性流体。在相同流动方式下,随着黄原胶含量的增加,淀粉糊的粘... 对3%马铃薯淀粉,黄原胶含量为0.2%、0.4%和0.6%的淀粉糊流变特性进行了探讨。静态流变特性测定结果表明,在实验范围内,不同黄原胶含量的淀粉糊的流变模型为幂率模型,均为假塑性流体。在相同流动方式下,随着黄原胶含量的增加,淀粉糊的粘度增加。动态流变特性测定结果表明,随着温度的增加,不同黄原胶含量淀粉糊的弹性模量、粘性模量逐渐下降,到62℃,两模量降低到某恒定最低值,温度继续增加,两模量急剧增加,到72℃后,两模量增加变缓。随着黄原胶含量的增加,两模量增加。 展开更多
关键词 黄原胶 淀粉 粘度 弹性模量 粘性模量
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4种马铃薯淀粉糊流变特性的研究 被引量:8
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作者 柴春祥 Sundaram Gunasekaran 《食品与发酵工业》 CAS CSCD 北大核心 2007年第5期76-79,共4页
对4种不同加工方式获得的马铃薯淀粉糊流变特性进行了探讨。静态流变特性测定结果表明,4种淀粉糊的流变模型为幂率模型,均为假塑性流体,每种淀粉糊以相同方式流动需要施加的力不同。在相同流动方式下,淀粉4粘度最大,其次为淀粉2,淀粉1... 对4种不同加工方式获得的马铃薯淀粉糊流变特性进行了探讨。静态流变特性测定结果表明,4种淀粉糊的流变模型为幂率模型,均为假塑性流体,每种淀粉糊以相同方式流动需要施加的力不同。在相同流动方式下,淀粉4粘度最大,其次为淀粉2,淀粉1和淀粉3的粘度近似相同。动态流变特性测定结果表明:随着温度的增加,淀粉1、2、4的弹性模量、粘性模量刚开始基本不发生变化,到60℃后,两模量急剧增加到最大值,然后降低到某恒定值。淀粉3的两模量随温度升高逐渐增加到最大值,然后逐渐降低到某恒定值。粘性模量达到最大后,淀粉2的粘性模量最大,其次为淀粉4、淀粉1,淀粉3的最低。弹性模量达到最大后,淀粉4的弹性模量最大,其次为淀粉2、淀粉1,淀粉3最低。 展开更多
关键词 淀粉 粘度 弹性模量 粘性模量
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基于超宽带无线定位的农业设施内移动平台路径跟踪研究 被引量:1
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作者 姚立健 Santosh K Pitla +2 位作者 杨自栋 夏坡坡 赵辰彦 《农业工程技术》 2023年第6期79-79,共1页
为实现农业设施内车辆自动导航,提出了一种基于超宽带(ultrawideband,UWB)无线定位的路径跟踪方法。运用4个基站组建UWB无线定位系统,采用加权最小二乘法(weighted least squares,WLS)法解超静定方程组,提高了移动标签的定位精度。重新... 为实现农业设施内车辆自动导航,提出了一种基于超宽带(ultrawideband,UWB)无线定位的路径跟踪方法。运用4个基站组建UWB无线定位系统,采用加权最小二乘法(weighted least squares,WLS)法解超静定方程组,提高了移动标签的定位精度。重新定义前视距离,根据车体航向与前视直线的夹角界定车体偏差程度,并提出基于动态前视距离的改进型纯追踪模型。在MATLAB 2016a软件环境下的仿真说明该文算法优于采用固定视距的传统纯追踪算法,并进行实车试验。结果显示,在UWB定位系统的引导下,车体在不同初始状态下均能很好地收敛到期望直线,当速度为0.5 m/s时,在4种初始状态下进行直线跟踪,稳态偏差为5.4~8.4 cm,稳态偏差均值为6.3 cm。在矩形路径跟踪时,当横向偏差和航向偏差均为0的初始状态下,全程平均偏差为20.6 cm,跟踪偏差主要出现在90°转向处,最大偏差为85.5 cm,说明改进后的纯追踪算法的路径追踪质量均优于采用固定视距的传统纯追踪模型,能满足农业设施内移动平台自动导航的需求。该方法可为农业设施内车辆导航提供新思路。 展开更多
关键词 农业机械 控制 模型 超宽带 纯追踪 动态前视距离 路径跟踪
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油茶籽储藏品质变化规律及条件优化 被引量:18
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作者 朱广飞 刘海 +4 位作者 李卫 刘嫣红 谢雨岑 张悦 谢永康 《农业工程学报》 EI CAS CSCD 北大核心 2020年第2期301-311,共11页
为探讨不同储藏条件下油茶籽品质的变化规律及其原因,找出适宜的储藏条件,该文分别以物料含水率、空气相对湿度和储藏温度为单因素,研究油茶籽储藏过程中的含油率、酸值、过氧化值等品质的变化规律及相应的脂肪酶、脂氧合酶活性,并对微... 为探讨不同储藏条件下油茶籽品质的变化规律及其原因,找出适宜的储藏条件,该文分别以物料含水率、空气相对湿度和储藏温度为单因素,研究油茶籽储藏过程中的含油率、酸值、过氧化值等品质的变化规律及相应的脂肪酶、脂氧合酶活性,并对微生物的生长情况进行统计分析。运用响应面法,综合考察上述因素对油茶籽品质的影响。结果表明:油茶籽的储藏过程存在3至4个月的后熟期,酸值、过氧化值均随含水率、温度和储藏时间的增加而升高。脂肪酶及微生物的繁殖与酸值的关系比较显著。优化的油茶籽储藏工艺参数为:空气相对湿度57.6%~67.4%,储藏温度17.2~20.4℃,物料含水率8.9%~10.4%和储藏时间62.2~110.3 d。该研究可为油茶籽储藏及后续加工提高出油率和保障品质提供技术支持。 展开更多
关键词 水分 储藏 品质控制 油茶籽 后熟 优化 参数
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Risk of colon cancer in hereditary non-polyposis colorectal cancer patients as predicted by fuzzy modeling:Influence of smoking 被引量:5
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作者 Rhonda M Brand David D Jones +4 位作者 Henry T Lynch Randall E Brand Patrice Watson Ramesh Ashwathnayaran Hemant K Roy 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第28期4485-4491,共7页
AIM: To investigate whether a fuzzy logic model could predict colorectal cancer (CRC) risk engendered by smoking in hereditary non-polyposis colorectal cancer (HNPCC) patients. METHODS: Three hundred and forty H... AIM: To investigate whether a fuzzy logic model could predict colorectal cancer (CRC) risk engendered by smoking in hereditary non-polyposis colorectal cancer (HNPCC) patients. METHODS: Three hundred and forty HNPCC mismatch repair (MMR) mutation carriers from the Creighton University Hereditary Cancer Institute Registry were selected for modeling. Age-dependent curves were generated to elucidate the joint effects between gene mutation (hMLH1 or hMSH2), gender, and smoking status on the probability of developing CRC. RESULTS: Smoking significantly increased CRC risk in male hMSH2 mutation carriers (P 〈 0.05). hMLH1 mutations augmented CRC risk relative to hMSH2 mutation carriers for males (P 〈 0.05). Males had a significantly higher risk of CRC than females for hMLH1 non smokers (P 〈 0.05), hMLH1 smokers (P 〈 0.1) and hMSH2 smokers (P 〈 0.1). Smoking promoted CRC in a dose-dependent manner in hMSH2 in males (P 〈 0.05). Females with hMSH2 mutations and both sexes with the hMLH1 groups only demonstrated a smoking effect after an extensive smoking history (P 〈 0.05). CONCLUSION: CRC promotion by smoking in HNPCC patients is dependent on gene mutation, gender and age. These data demonstrate that fuzzy modeling may enable formulation of clinical risk scores, thereby allowing individualization of CRC prevention strategies. 展开更多
关键词 Hereditary non-polyposis colorectal cancer Lynch syndrome SMOKING Colorectal cancer Fuzzy modeling Risk assessment
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Enhancing Biogas Production from Anaerobically Digested Wheat Straw Through Ammonia Pretreatment 被引量:4
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作者 杨懂艳 庞云芝 +4 位作者 袁海荣 陈树林 马晶伟 郁亮 李秀金 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第5期576-582,共7页
Aqueous ammonia was used to pretreat wheat straw to improve biodegradability and provide nitrogen source for enhancing biogas production. Three doses of ammonia(2%, 4%, and 6%, dry matter) and three moisture contents(... Aqueous ammonia was used to pretreat wheat straw to improve biodegradability and provide nitrogen source for enhancing biogas production. Three doses of ammonia(2%, 4%, and 6%, dry matter) and three moisture contents(30%, 60%, and 80%, dry matter) were applied to pretreat wheat straw for 7 days. The pretreated wheat straws were anaerobically digested at three loading rates(50, 65, and 80 g·L-1) to produce biogas. The results indicated that the wheat straw pretreated with 80% moisture content and 4% ammonia achieved the highest methane yield of 199.7 ml·g-1(based on per unit volatile solids loaded), with shorter digestion time(T80) of 25 days at the loading rate of 65 g·L-1compared to untreated one. The main chemical compositions of wheat straw were also analyzed. The cellulose and hemicellulose contents were decomposed by 2%-20% and 26%-42%, respectively,while the lignin content was hardly removed, cold-water and hot-water extracts were increased by 4%-44%, and12%-52%, respectively, for the ammonia-pretreated wheat straws at different moisture contents. The appropriate C/N ratio and decomposition of original chemical compositions into relatively readily biodegradable substances will improve the biodegradability and biogas yield. 展开更多
关键词 wheat straw anaerobic digestion BIOGAS ammonia pretreatment moisture content
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CO_2 Removal from Biogas by Water Washing System 被引量:4
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作者 肖勇 袁海荣 +6 位作者 庞云芝 陈树林 朱保宁 邹德勋 马晶伟 郁亮 李秀金 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第8期950-953,共4页
CO2 removal from biogas by water washing system was investigated with various parameters, including liquid/ gas ratio, pressure, temperature, and CO2 content. The results indicate that CO2 removal ratio could reach 34... CO2 removal from biogas by water washing system was investigated with various parameters, including liquid/ gas ratio, pressure, temperature, and CO2 content. The results indicate that CO2 removal ratio could reach 34.6%- 94.2% as liquid/gas ratio increased from 0.14 to 0.50. Increasing pressure (from 0.8 to 1.2 MPa) could improve gas purification with a constant inflow rate of gas. Temperature played a key role in the process and lower temper- ature in absorption tower was beneficial for reducing CO2 content. CO2 removal ratio could reach 24.4%-83.2% when CO2 content in the simulated gas was 25%-45%. The lowest CO2 content after absorption was 2.6% at 1.2 MPa with 400 L·h-1 gas flow and 200 L·h-1 water flow, which meets the requirement of CO2 content in natural Ras for vehicle fuel. 展开更多
关键词 Biogas purification C02 removal Water washing Pilot system
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流体/半流体物料连续流射频加热辅助装置设计与试验
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作者 张浩 仵明太 +2 位作者 张一鸣 王绍金 令博 《农业工程学报》 EI CAS CSCD 北大核心 2024年第19期33-41,共9页
针对流体/半流体物料在流动状态下开展射频杀菌、钝酶、提取时加热不均匀的问题,该研究设计了一套适用于英国Strayfield SO6B型射频加热系统的流体/半流体物料连续流辅助装置。该装置主要由蠕动泵、电动机、料槽和控制系统等组成,料槽... 针对流体/半流体物料在流动状态下开展射频杀菌、钝酶、提取时加热不均匀的问题,该研究设计了一套适用于英国Strayfield SO6B型射频加热系统的流体/半流体物料连续流辅助装置。该装置主要由蠕动泵、电动机、料槽和控制系统等组成,料槽内部装有一组剪切折叠满面式螺旋桨实现对物料的混合搅拌。选取生牛乳、羧甲基纤维素(carboxymethylcellulose,CMC)溶液以及苹果渣-柠檬酸混合溶液(PS)3种物料分别进行射频处理,结果显示,相同条件下3种物料的升温速率从大到小依次为生牛乳、CMC溶液、PS,且在20 min内所有物料即可达到目标温度,证实该装置可以辅助不同特性流体/半流体物料实现射频连续均匀加热。与无螺旋搅拌相比,在物料静止状态,螺旋搅拌可以改善射频加热均匀性,其中CMC溶液改善最为明显,其射频加热均匀性指数由0.139降为0.068;在物料流动状态,螺旋搅拌可以改善CMC溶液与果渣粒径为5 mm的苹果渣-柠檬酸混合溶液(PS5)的加热均匀性,CMC溶液和果渣粒径PS5的最大温差分别下降了13.4和11.4℃,但在低速搅拌时固液混合物料易因颗粒漂浮而降低加热均匀性。整体来看,该装置可以实现流体/半流体物料的射频连续均匀化处理,可为该类物料的射频连续化加热及工业化处理提供技术与理论支持。 展开更多
关键词 射频 连续流 流体/半流体 加热均匀性 辅助装置
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Effect on anaerobic digestion performance of corn stover by freezing–thawing with ammonia pretreatment 被引量:3
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作者 Hairong Yuan Yanyan Lan +3 位作者 Jialin Zhu Akiber Chufo Wachemo Xiujin Li Liang Yu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第1期200-207,共8页
In order to enhance the biomethane production from corn stover, choosing effective pretreatment is one of the necessary steps before starting anaerobic digestion(AD).This study was aimed to analyze the effectiveness o... In order to enhance the biomethane production from corn stover, choosing effective pretreatment is one of the necessary steps before starting anaerobic digestion(AD).This study was aimed to analyze the effectiveness of freezing–thawing with ammonia pretreatment on substance degradation and AD performance of corn stover.Three ammonia concentrations(2%, 4%, and 6%) with two different moisture contents(50% and 70%) were used to pretreat the corn stover at two temperatures(-20 ℃ and 20 ℃).The result showed that an optimum pretreatment condition for corn stover was at the temperature of -20 ℃, moisture content of 70% and ammonia concentration of 2%.Under the optimum pretreatment condition, the maximum biomethane yield reached 261 ml·(g VS)^(-1), which was 41.08% higher than that of the untreated.Under different pretreatment conditions,the highest loss of lignin at -20 ℃ with 2% ammonia concentration was 63.36% compared with the untreated.The buffer capacity of AD system was also improved after the freezing–thawing with ammonia pretreatment.Therefore, the freezing–thawing with ammonia pretreatment can be used to improve AD performance for corn stover.This study provides further insight for exploring an efficient freezing–thawing with ammonia pretreatment strategy to enhance AD performance for the practical application. 展开更多
关键词 Freezing–thawing AMMONIA PRETREATMENT Anaerobic DIGESTION Corn STOVER
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Nitric oxide-mediated S-nitrosylation of IAA17 protein in intrinsically disordered region represses auxin signaling 被引量:6
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作者 Hongwei Jing Xiaolu Yang +8 位作者 Ryan J.Emenecker Jian Feng Jian Zhang Marcelo Rodrigues Alves de Figueiredo Patarasuda Chaisupa R.Clay Wright Alex S.Holehouse Lucia C.Strader Jianru Zuo 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2023年第7期473-485,共13页
The phytohormone auxin plays crucial roles in nearly every aspect of plant growth and development.Auxin signaling is activated through the phytohormone-induced proteasomal degradation of the Auxin/INDOLE-3-ACETIC ACID... The phytohormone auxin plays crucial roles in nearly every aspect of plant growth and development.Auxin signaling is activated through the phytohormone-induced proteasomal degradation of the Auxin/INDOLE-3-ACETIC ACID(Aux/IAA)family of transcriptional repressors.Notably,many auxin-modulated physiological processes are also regulated by nitric oxide(NO)that executes its biological effects predominantly through protein S-nitrosylation at specific cysteine residues.However,little is known about the molecular mechanisms in regulating the interactive NO and auxin networks.Here,we show that NO represses auxin signaling by inhibiting IAA17 protein degradation.NO induces the S-nitrosylation of Cys-70 located in the intrinsically disordered region of IAA17,which inhibits the TIR1-IAA17 interaction and consequently the proteasomal degradation of IAA17.The accumulation of a higher level of IAA17 attenuates auxin response.Moreover,an IAA17^(C70W)nitrosomimetic mutation renders the accumulation of a higher level of the mutated protein,thereby causing partial resistance to auxin and defective lateral root development.Taken together,these results suggest that S-nitrosylation of IAA17 at Cys-70 inhibits its interaction with TIR1,thereby negatively regulating auxin signaling.This study provides unique molecular insights into the redox-based auxin signaling in regulating plant growth and development. 展开更多
关键词 Arabidopsis thaliana AUXIN AUX/IAA Nitric oxide S-NITROSYLATION Intrinsically disordered region
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Evaluation of UAV-derived multimodal remote sensing data for biomass prediction and drought tolerance assessment in bioenergy sorghum 被引量:3
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作者 Jiating Li Daniel P.Schachtman +3 位作者 Cody F.Creech Lin Wang Yufeng Ge Yeyin Shi 《The Crop Journal》 SCIE CSCD 2022年第5期1363-1375,共13页
Screening for drought tolerance is critical to ensure high biomass production of bioenergy sorghum in arid or semi-arid environments. The bottleneck in drought tolerance selection is the challenge of accurately predic... Screening for drought tolerance is critical to ensure high biomass production of bioenergy sorghum in arid or semi-arid environments. The bottleneck in drought tolerance selection is the challenge of accurately predicting biomass for a large number of genotypes. Although biomass prediction by lowaltitude remote sensing has been widely investigated on various crops, the performance of the predictions are not consistent, especially when applied in a breeding context with hundreds of genotypes. In some cases, biomass prediction of a large group of genotypes benefited from multimodal remote sensing data;while in other cases, the benefits were not obvious. In this study, we evaluated the performance of single and multimodal data(thermal, RGB, and multispectral) derived from an unmanned aerial vehicle(UAV) for biomass prediction for drought tolerance assessments within a context of bioenergy sorghum breeding. The biomass of 360 sorghum genotypes grown under well-watered and water-stressed regimes was predicted with a series of UAV-derived canopy features, including canopy structure, spectral reflectance, and thermal radiation features. Biomass predictions using canopy features derived from the multimodal data showed comparable performance with the best results obtained with the single modal data with coefficients of determination(R2) ranging from 0.40 to 0.53 under water-stressed environment and0.11 to 0.35 under well-watered environment. The significance in biomass prediction was highest with multispectral followed by RGB and lowest with the thermal sensor. Finally, two well-recognized yieldbased drought tolerance indices were calculated from ground truth biomass data and UAV predicted biomass, respectively. Results showed that the geometric mean productivity index outperformed the yield stability index in terms of the potential for reliable predictions by the remotely sensed data.Collectively, this study demonstrated a promising strategy for the use of different UAV-based imaging sensors to quantify yield-based drought tolerance. 展开更多
关键词 Crop phenotyping Unmanned Aerial System(UAS) Thermal Machine learning Drought stress
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