Anti-quorum sensing and anti-biofilm formation activities of plant extracts from South Korea

Objective: To investigate anti-quorum sensing(anti-QS) and anti-biofilm formation(antiBF) activities of the ethanol extracts of 388 plants. Methods: The anti-QS activity of the plant extracts was evaluated by disc-diffusion assays using the bio-reporter strain, Chromobacterium violaceum CV017. Pseudomonas aeruginosa PAO1, Yersinia enterocolitica ATCC 9610, and Agrobacterium tumefaciens C58, which possess QS systems, were used to evaluate the antiBF activity of the plant extracts. Results: Among 388 plant extracts, the Cornus controversa(C. controversa) and Cynanchum wilfordii extracts exhibited the strongest anti-QS activity. The C. controversa extract exhibited anti-BF activity against Pseudomonas aeruginosa, Yersinia enterocolitica and Agrobacterium tumefaciens, whereas the Cynanchum wilfordii extract exhibited no anti-BF activity against Pseudomonas aeruginosa. In addition, the C. controversa extract suppressed soft rot of cabbage. Conclusions: The C. controversa extract inhibits bacterial QS and BF, and is capable of controlling soft rot. Therefore, this extract has potential for the prevention and treatment of bacterial infections and for the development of alternatives to antibiotics.

Effect of Ethanol Extract of Venenum Bufonis on Biofilm Formation of <i>Staphylococcus aureus</i>

Ethanol extract of Venenum Bufonis has shown many valuable bioactivities, but little is known about its effect on biofilm formation of Staphylococcus aureus. In this study, biofilm formation of S. aureus NCTC8325 with or without ethanol extract of Venenum Bufonis was tested using microtitre plate assay and Confocal Laser Scanning Microscope (CLSM) system. Results show that the biofilm formation of S. aureus with ethanol extract of Venenum Bufonis was significantly lower than that of the control group without ethanol extract of Venenum Bufonis. Meanwhile, the reduction degree was correlated to the concentration of ethanol extract of Venenum Bufonis positively. With CLSM system we can observe that looser and less biomass of the biofilm structure of the experimental group appeared than that of the control group. These results suggested that ethanol extract of Venenum Bufonis has inhibitory effect on biofilm formation of S. aureus.

Determination of Lisinopril in Bulk and Pharmaceutical Formulations by Cloud Point Extraction—A Green Method

A sensitive and eco-friendly method was developed for the spectrophotometric determination of Lisinopril (LSP) in bulk and pharmaceutical formulations by cloud point extraction technique. The method was based on the formation of a blue-colored coordination complex between Lisinopril (LSP) and Cobalt Thiocyanate (CTC) at a suitable pH. The Complex in aqueous medium was extracted into surfactant layer by cloud point extraction using a non-ionic surfactant Triton X-114 and then the surfactant layer was dissolved in a suitable volume of ethanol and the amount of Lisinopril was determined spectrophotometrically at a wavelength of 625 nm. The conditions like concentration of the drug, concentration of CTC and of Triton X-114, PH, etc. were optimized by OFAT (One Factor At a Time) method. The linear range of calibration curve was 1 - 6 μg/ml and the linear regression equation with a correlation coefficient of 0.99996 was y = 0.0021 + 0.084x. Preconcentration and enrichment factors were found to be 100 and 3.12 respectively, achieving the detection limit of 0.0588 μg/ml. The proposed method was successfully applied for the determination of LSP in the drug formulations. The obtained values were in agreement with the values as quoted by the manufacturers.

Performance Analysis of Optimized Content Extraction for Cyrillic Mongolian Learning Text Materials in the Database

This paper had developed and tested optimized content extraction algorithm using NLP method, TFIDF method for word of weight, VSM for information search, cosine method for similar quality calculation from learning document at the distance learning system database. This test covered following things: 1) to parse word structure at the distance learning system database documents and Cyrillic Mongolian language documents at the section, to form new documents by algorithm for identifying word stem;2) to test optimized content extraction from text material based on e-test results (key word, correct answer, base form with affix and new form formed by word stem without affix) at distance learning system, also to search key word by automatically selecting using word extraction algorithm;3) to test Boolean and probabilistic retrieval method through extended vector space retrieval method. This chapter covers: to process document content extraction retrieval algorithm, to propose recommendations query through word stem, not depending on word position based on Cyrillic Mongolian language documents distinction.

Treatment Effect of Various Concentration of Plant Extracts on Murine Norovirus

Noroviruses are positive-sense, single-stranded, non-enveloped RNA virus that measures approximately 27 - 35 nm in diameter. It affects humans of all ages and races causing most cases of viral gastroenteritis worldwide. Infection results from ingestion of contaminated food or water as well as causing diarrhea and vomiting in humans. Extracts from plants are known to have antioxidant, anti-inflammatory, and adhesive properties which are associated with barrier functions. The aim of this study was to elucidate whether plaque reduction was due to an effect of methanolic plant extract directly on the virus, whether the extract affects viral replication, and lastly, whether the extract disrupts the cell surface binding with the virus. The plant extracts of interest were the calyces of Hibiscus sabdariffa (HS) and the seeds of Zanthoxylum armatum (ZA). Antiviral activities of these extracts were determined against murine norovirus. The logarithmic viral reduction per plaque-forming unit was (22 log10) PFU/ml (control), (15 log10) PFU/ml (treated HS), and (12 log10) PFU/ml (treated ZA) with a significant reduction (68% and 55% respectively) when compared with the control for the direct effect on the virus. The role of extracts on virus replication showed (25 log10) PFU/ml (control) as against the HS treated-virus-infected cells (9 log10) PFU/ml and ZA treated-virus-infected cells (5 log10) PFU/ml (36% and 20% respectively). Finally, effect of the extract on the viral attachment showed (31 log10) PFU/ml (control), (12 log10) (HS-treated) and (9 log10) PFU/ml (ZA-treated), (39% and 29% respectively. Extract treatment with HS and ZA has shown evidence of a reduced number of plaques formation with the latter having fewer plaques. Both extracts have proven potential to reduce the viral multiplication process by interfering with the replication process. This study shows that Hibiscus sabdariffa (calyces) and Zanthoxylum armatum (seed) extracts disrupt murine norovirus from consistent viral replication.

城市浅层地热能开发地质环境问题研究

本文就浅层地热能开发利用过程中出现的生态环境和地质环境问题从客观因素和人为因素进行了详细的研究,借助土壤温度的测试和地层冷热平衡的监测,分析在地源热泵运行过程中造成的热污染、地下水位下降、地面沉降、地下水质恶化污染等问题。研究认为长期利用地源热泵开发利用系统,如设计不合理或地下水回灌率低,将破坏地层的冷热平衡。北方地区供暖期大于制冷期时,地层温度将逐年下降,N2O和CH4会集中释放,造成生物生长速度缓慢。地下水源热泵运行时,如地下水回灌困难,将导致地下水资源浪费、水位下降等生态环境问题以及路面塌陷、地面沉降等地质环境问题。供暖期、制冷期运行时间差别较大时,将导致地下水温度的变化,直接影响地下水中污染物的降解,间接影响地下水的水质。抽取、回灌地下水的过程会造成空气中的氧气随之溶解于水中,导致地下水质的变化。通过分析浅层地热能开发利用存在的突出问题和影响因素,可为其科学合理开发利用提供科学依据和技术支撑。

微多普勒辅助的城市环境无人机编队检测方法

针对城市复杂环境下电磁环境复杂、多径杂波和干扰信号密集等现象,传统的无人机(UAV)检测方法通过获取回波信号提取目标多普勒信息进行检测,易受到环境影响导致检测效果不理想。该文提出微多普勒辅助的城市环境无人机编队检测方法,充分利用无人机的微动特征,能够在复杂环境下提高检测精度。首先,参数化建模表征城市复杂环境下无人机旋翼的雷达回波微多普勒信号,利用YOLOv5s检测微多普勒闪烁脉冲,有效提取位置信息;然后,引入雷达信号分选方法的脉冲重复间隔(PRI)变换,分类获得无人机编队数量;最后,利用Kmeans算法验证无人机编队检测方法的准确性。结果表明,所提方法在信噪比2 dB时7架无人机的检测精度高于90%,能够用于城市复杂环境存在干扰脉冲、多径效应、局部脉冲丢失的无人机编队检测。

高效液相色谱-质谱法测定油藏地层水和土壤中甜菜碱型表面活性剂的样品处理

比较了测定油藏地层水和土壤这类复杂基质中3种甜菜碱型表面活性剂的样品净化方法。选用直接过微孔滤膜、活性炭固相萃取柱、碱性氧化铝固相萃取柱、HLB固相萃取柱、MCX固相萃取柱、WCX固相萃取柱,对10、50、100 mg/L质量浓度下的回收率对比分析,并结合高效液相色谱-质谱联用全扫描质谱图甄选较优净化手段。分析结果显示,采用混合型强阳离子交换柱(MCX固相萃取柱)进行净化提取后,用高效液相色谱-质谱联用法进行检测,3种甜菜碱型表面活性剂在质量浓度10~50 mg/L内与色谱峰面积线性良好,相关系数均达到0.99以上,检出限为0.01 mg/L。加标回收率为96.9%~100.5%,相对标准偏差为0.7%~2.1%(n=7)。该方法操作简单,特异性强,作为复杂基质中甜菜碱型表面活性剂净化最佳方法,为甜菜碱型表面活性剂的检测提供坚实的基础。

植物基肉制品的减钠策略研究进展

随着人口增长和环境恶化等问题的加剧,传统畜牧业的不良影响逐渐凸显,植物基肉制品的市场正在扩大。诸多研究正集中于从外观、结构和口感风味等方面改善植物基肉制品的品质,使其与真肉更为相似。但是,目前市场上的植物基肉制品普遍存在钠元素偏高的现状,这与健康饮食的观念相悖,严重影响了植物基肉制品的营养价值和推广应用。因此,本文从植物基肉制品的发展情况入手,对相关产品的高钠现状和原因进行分析,并重点阐述了植物基肉制品在生产加工过程的口感风味塑造、纤维结构构建以及原料生产环节的减盐降钠策略,以期在不影响产品感官品质的前提下实现钠含量的降低,从而生产和推广更加健康的低钠型植物基肉制品。

大幅面高光谱扫描系统在文物研究中的应用

为使高光谱成像技术能够在大幅面绘画类文物研究和保护中充分发挥面分析的优势,研制了大幅面高光谱扫描系统,同时建立了传统颜料数据库。与以往高光谱成像技术对文物进行的局部分析相比,该系统不仅提高了分析效率,而且可对绘画文物整体进行颜料鉴别和相对浓度分布研究,可以为绘画中复杂调色工艺的研究提供巨大的帮助。目前,已使用该系统对故宫博物院东华门天花彩画、纸本书画《丁观鹏画不二尊者图轴》、绢本书画《沈庆兰画贴落》和唐卡《吉祥天母画佛像》进行分析研究,并将其用于文物隐藏病害、隐藏墨迹、底稿线等信息的提取与增强,颜料成分鉴别和混合颜料工艺研究等方面,取得了良好的效果,对绘画类文物的研究与保护具有重要的意义。

CLGLF:置信学习引导标签融合的多模态命名实体识别方法

为解决多模态命名实体识别中存在的视觉语义理解和多模态语义的偏差问题,本文提出了置信学习引导标签融合的多模态命名实体识别方法 .该方法调用BLIP-2预训练模型生成图像描述,将其与输入的文本拼接,进行图文联合编码实现多模态特征融合,对多模态表征和文本表征解码后得到候选标签和文本标签;在采用KL散度损失函数对齐两组标签的基础上,计算置信分数用来评估多模态表征质量,设置置信阈值辅助筛选出有偏差的候选标签,并使用相应位置的文本标签替换有偏差的候选标签,实现标签的融合,最终完成多模态命名实体识别.为了验证本文方法,在Twitter-2015和Twitter-2017多模态数据集上进行实验,并将实验结果与MSB、UMT等7种主流方法进行对比,实验结果证明了本文方法的有效性.

水产品挥发性风味化合物生成机理及其分析技术研究进展

水产品是海洋和淡水渔业生产的水产动植物产品及其加工产品的总称,营养丰富,蛋白质含量是禽畜产品的2~4倍,且易于人体吸收,含有维生素和矿物质(如维生素D、硒、磷和钙等)。此外,水产品提供的n-3多不饱和脂肪酸,包括二十碳五烯酸和二十二碳六烯酸,对大脑发育起着重要作用^([1])。随着我国居民收入、生活水平提高,国民膳食结构逐渐优化,水产品的食物健康功能越来越受到重视,水产品在居民膳食中的比重越来越高,消费需求量也越来越大。根据《中华人民共和国2021年国民经济和社会发展统计公报》报道,2021年我国全年水产品产量6693万t,比上年增长2.2%。2021年渔业产值14 507亿元,比2012年增加6103亿元,2013—2021年年均增长3.4%^([2])。

基于深度学习的二进制变种协议字段划分方法

为提高二进制变种协议字段格式划分的准确率,提出一种基于深度学习的方法,能够自动挖掘协议报文序列的深层字段特征完成协议的字段格式划分。引入一种字段列特征数据集的提取方法,在传统的双向长短期记忆条件随机场网络模型的基础上增加协议字段列特征提取模块,搭建一种专门解决二进制变种协议字段格式划分的神经网络PRO-BILSTM-CRF。与二进制未知协议字段格式划分方法以及几种主流网络模型的对比实验结果表明,在变种协议字段格式划分任务上,提出模型能够取得更高准确率。

The occurrence characteristics of oil in shales matrix from organic geochemical screening data and pore structure properties:An experimental study Author links open overlay panel

The occurrence characteristics of shale oil are of great significance to the movability of shale oil.In this study,the occurrence characteristics of oil in the shale matrix at Funing Formation shale in Subei Basin were quantitatively evaluated by organic geochemistry and microscopic pore structure characterization experiments.The Multiple Isothermal Stages Pyrolysis(MIS)experiment results show that the content of total oil,adsorbed oil,and free oil in the shales are 3.15-11.25 mg/g,1.41-4.95 mg/g,and 1.74-6.51 mg/g,respectively.among which the silicon-rich shale has the best oil-bearing.The relative content of free oil shows an increasing trend in pores with pore diameters greater than 3 nm.When the relative content of free oil reaches 100%,the pore size of silicon-rich shale is about 200 nm,while that of calcium-rich shale,clay-rich shale,and siliceous mixed shale is about 10 nm.The occurrence law of adsorbed oil is opposite to that of free oil,which indicates that shale oil will occur in the pores and fractures in a free state in a more extensive pore size range(>200 nm).This study also enables us to further understand the occurrence characteristics of shale oil under the interaction of occurrence state and occurrence space.

时频电磁法在深层页岩气有利区预测中的应用

时频电磁法基于时—频域、电—磁场一体化探测理念,实现了多信息联合,弥补了传统电磁方法抗干扰能力不足的缺点,集成了可控源电磁法的优点:探测深度大,精度高,抗干扰能力强。在四川泸州地区开展时频电磁勘探,结合岩石物理和测井数据,对宝藏—云锦向斜的志留系五峰组—奥陶系龙马溪组页岩层系进行页岩气有利区预测。对本区外露头信息和电阻率测井数据进行统计,结果表明页岩含气性与电阻率具有相关性,高电阻率页岩段普遍表现出较高的含气性,本区具有开展电法勘探的物性基础。研究区不同地层之间存在明显的电性差异,纵向可划分为高、低相间的6套电性层,其中页岩气主力产层五峰—龙马溪组与上、下围岩电阻率差异明显。从时频电磁勘探原理出发,利用一维有限元和有限差分方法进行数值模拟,研究方法的可行性,并根据正演结果设计最佳采集参数。在围绕目的层进行针对性数据采集的基础上,采用自主研发的重、磁、电处理解释系统GeoGME进行数据处理解释,通过弱异常信息提取和井震双控约束反演等关键技术,探明了龙一1亚段各小层的电阻率和极化率分布特征。综合考虑目标页岩层段电阻率异常和极化率异常,预测出页岩气勘探有利区4个,为下一步该区域页岩气钻井部署提供了技术支撑,表明时频电磁法是进行深层页岩气有利区预测的有效勘探手段。

复杂地层中底板梳状钻孔抽采技术的应用研究

在当前的煤矿开采中,部分煤层有着煤质松软、厚度较薄、瓦斯压力大等特点,难以高效地进行瓦斯抽采作业。为此,先概述梳状定向钻孔抽采技术,然后以一煤矿+960 m水平运输延伸巷的掘进为例,明确该矿的基本地质特点。其次,结合实际分析了抽采钻孔设计及具体施工,共设计了7个主定向钻孔,并以主钻孔为主干又增加了56个梳状分支。最后,对该技术进行了实践应用,并对抽采效果进行了讨论,单孔平均瓦斯抽采体积分数及平均瓦斯抽采纯量皆较高,能提高巷道掘进期间的安全性。

清洁设备流体抽取组件的设计与性能评估

系统研究了清洁设备的流体抽取组件设计与性能,重点是其在洗涤容器内形成负压的能力及洗涤效率影响.研究通过分析抽取速度、效率及对流体动力学的影响,评估了多种设计方案.结果显示:优化的组件设计显著提升了洗涤效率与降低能耗.研究还探讨了通过改进流体入口和出口配置,以提升设备性能和可靠性的方法.这为清洁设备设计和性能优化提供了理论和实用指导.

络合法从大豆油脱臭馏出物中提取植物甾醇的工艺研究

以提取维生素E后的大豆油脱臭馏出物的甲酯化物为原料,探索了用氯化钙络合法提取植物甾醇的工艺。原料中存在的甾醇酯经过转酯化反应析出游离甾醇。游离甾醇与氯化钙起络合反应,得到络合物。分解该络合物得到甾醇。对溶剂的种类,溶剂、氯化钙、甲醇用量,反应温度,反应时间等影响因素进行了考察,得到了优化的操作条件。优化的工艺条件为:非质子溶剂为乙酸乙酯,质子溶剂为甲醇,乙酸乙酯与原料、甲醇与氯化钙的质量比分别为1:1、1:2,氯化钙与原料中甾醇的摩尔比为4:1,反应温度40℃,反应时间1h。在上述条件下,甾醇产品的含量达到96%以上,收率达到75%以上。得到了一条从大豆油脱臭馏出物中提取甾醇的新工艺路线。

从WEB文档中构造半结构化信息的抽取器

为了对 WEB上不规则的、动态的信息按照数据库的方式集成和查询 ,采用对象交换模型 (object ex-change model,简称 OEM)建立了 WEB信息模型 .为了将页面中各个部分表示为对应的 OEM对象 ,设计了半结构化信息的抽取算法 ,并给出测试结果 .该方法可以抽取结构化和半结构化的信息 ,比现有的抽取方法通用性更强 .

煤的族组分形成机理研究

采用CS2/NMP混合溶剂和反萃取剂,将徐州夹河煤在常温常压下分离为萃余煤组分、沥青质组分、精煤组分和轻质组分四大族组分,通过扫描电镜(SEM)对混合溶剂萃取、反萃取过程进行了追踪研究,主要探讨了族组分中精煤组分和沥青质组分形成的微观机理.结果表明,精煤组分和沥青质组分均是以微纳米颗粒形式从煤大分子基质悬浮到萃取液中,两种颗粒在后续反萃取过程中均发生融并现象.以深灰色呈现的精煤组分颗粒在加入反萃取剂后,融并为网孔状或表层均一的块体;以灰白色(或亮白色)呈现的沥青质组分颗粒在加入反萃取剂前后由分散聚集变为高度聚集,进一步融并成表面极为光滑均一的块体,最后经历了合并和长大的过程,于少量NMP中重新分散成大小均匀的小球体.