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American Journal of Analytical Chemistry 2011年第2期2卷 223-234页

作者： Arnaldo Aguiar Castro ricardo queiroz aucélio Nicolás Adrián Rey Eliane Monsores Miguel Percio Augusto Mardini Farias 不详

This paper describes a stripping method for the determination of zidovudine at the submicromolar concentration levels. This method is based on the controlled adsorptive accumulation of zidovudine at the thin-film mercury electrode, followed by a linear-sweep stripping voltammetry measurement of the surface species. Optimal experimental conditions include a NaOH solution of 2.0 × 10–3 mol●L–1 (sup-porting electrolyte), an accumulation potential of –0.30 V and a scan rate of 100 mV?s–1. The response of zidovudine is linear over the concentration range 0.01 - 0.08 ppm. After an accumulation time of 5 minutes, the detection limit was found to be 0.67 ppb (2.5 × 10–9 mol●L–1). More convenient methods to measure zidovudine concentration in the presence of the didanosine, acyclovir, nevirapine, lamivudine, and efavirenz, were also investigated. The presence of zidovudine together with ATP or ssDNA demonstrates the utility of this method.

关键词： Zidovudine Determination Antiviral Drugs Ssdna Thin-Film Mercury Electrode Stripping Voltammetry

A Review of Recent Advances in Hybrid Natural Fiber Reinforced Polymer Composites

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Journal of Renewable Materials 2022年第3期10卷 561-589页

作者： Jorge Neto Henrique queiroz ricardo Aguiar Rosemere Lima Daniel Cavalcanti Mariana Doina Banea Federal Centre of Technological Education in Rio de Janeiro(CEFET/RJ) Rio de JaneiroBrazil

Natural fiber reinforced polymer composites(NFRCs)have demonstrated great potential for many different applications in various industries due to their advantages compared to synthetic fiber-reinforced composites,such as low environmental impact and low ***,one of the drawbacks is that the NFRCs present relatively low mechanical properties and the absorption of humidity due to the hydrophilic characteristic of the natural *** method to increase their performance is ***,understanding the properties and potential of using multiple reinforcement’s materials to develop hybrid composites is of great *** paper provides an overview of the recent advances in hybrid natural fiber reinforced polymer ***,the main factors that affect the performance of hybrid fiber-reinforced composites were briefly *** effect of hybridization on the mechanical and thermal properties of hybrid composites reinforced with several types of natural fibers(i.e.,sisal,jute,curauá,ramie,banana,etc.)or natural fibers combined with synthetic fibers is ***,the water absorption behaviour of hybrid fiber-reinforced composites is also *** was con-cluded that the main challenges that need to be addressed in order to increase the use of natural-natural or natural-synthetic hybrid composites in industry are the poor adhesion between natural fibers and matrix,thermal stability and moisture absorption of natural *** of these challenges were addressed by recent develop-ment in fibers treatment and modification,and product innovation(hybridization).

关键词： Natural fiber composites(NFC) hybrid composites mechanical properties thermal properties water absorption

Anti-inflammatory natural products modulate interleukins and their related signaling markers in inflammatory bowel disease:A systematic review

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Journal of Pharmaceutical Analysis 2023年第12期13卷 1408-1428页

作者： Gopalsamy Rajiv Gandhi Thiruchenduran Mohana Kumaraswamy Athesh Varghese Edwin Hillary Alan Bruno Silva Vasconcelos Mariana Nobre Farias de Franca Monalisa Martins Montalvão Stanislaus Antony Ceasar Gnanasekaran Jothi Gurunagarajan Sridharan ricardo queiroz Gurgel Baojun Xu Division of Phytochemistry and Drug Design Department of BiosciencesRajagiri College of Social Sciences(Autonomous)KalamaserryKochi683104KeralaIndia Department of Biochemistry Meenakshi Ammal Dental College and Hospital(MAHER)Maduravoyal600095ChennaiTamil NaduIndia Department of Biochemistry Srimad Andavan Arts and Science College(Autonomous)Affiliated to Bharathidasan UniversityTiruchirapalli620005Tamil NaduIndia Division of Plant Molecular Biology and Biotechnology Department of BiosciencesRajagiri College of Social Sciences(Autonomous)KalamaserryKochi683104KeralaIndia Laboratory of Biology and Immunology of Cancer and Leishmania Department of MorphologyFederal University of SergipeSao CristovaoSergipeBrazil Postgraduate Program in Health Sciences(PPGCS) Federal University of Sergipe(UFS)Campus Prof.Joao Cardoso NascimentoAracajuCEP 49060.108SergipeBrazil Programme of Food Science and Technology Department of Life SciencesBNU-HKBU United International CollegeZhuhaiGuangdong519087China

This review aims to identify in vivo studies investigating the potential of plant substances and their natural molecules in managing inflammatory bowel disease(IBD).Specifically,the objective is to examine the impact of these substances on interleukins and other key inflammatory signaling *** articles published up to December 2022 were identified through a search of the PubMed,Scopus,Web of Science,and Embase *** search used keywords including“inflammatory bowel disease”,“medicinal plants”,“natural molecules”,“anti-inflammatory”,and“ulcerative colitis”,and identified 1,878 potentially relevant articles,of which 89 were included in this review after completion of the selection *** study provides preclinical data on natural products(NPs)that can potentially treat IBD,including ulcerative *** main actions of these NPs relate to their effects on nuclear factor kappa B(NF-κβ),the Janus kinase(JAK)/signal transducer and activator of transcription(STAT)signaling pathway,the regulation of T helper 17/regulatory T cells balance,and oxidative *** ability of these NPs to inhibit intestinal inflammation appears to be dependent on lowering levels of the pro-inflammatory cytokines tumor necrosis factor-alpha(TNF-α),interleukin(IL)-1β,and IL-17,via the Jun N-terminal kinase(JNK)1,NF-κβ-p65,and STAT3 *** addition,NPs were shown to reduce oxidative stress and the severity of ulcerative colitis,as well as increase the activity of antioxidant *** actions suggest that NPs represent a promising treatment for IBD,and potentially have greater efficacy and safety than current treatments.

关键词： Crohn's disease Inflammation Interleukins Oxidative stress Phytochemicals Ulcerative colitis

Areas with evidence of equity and their progress on mortality from tuberculosis in an endemic municipality of southeast Brazil

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Infectious Diseases of Poverty 2017年第1期6卷 1185-1195页

作者： Mellina YAMAMURA Marcelino SANTOS NETO Francisco CHIARAVALLOTI NETO Luiz Henrique ARROYO Antonio Carlos Vieira RAMOS Ana Angelica Rego de queiroz Aylana de Souza BELCHIOR Danielle Talita dos SANTOS Juliane de Almeida CRISPIM Ione Carvalho PINTO Severina Alice da Costa UCHOA Regina Celia FIORATI ricardo Alexandre ARCENCIO School of Nursing of the University of Sao Paulo Ribeirao Preto Campus(EERP/USP)Ribeirao retoSPBrazil Federal University of Maranhao(UFMA) Sao LuísMABrazil School of Public Health of the University of Sao Paulo(FSP/USP) Sao PauloSPBrazil Federal University of Rio Grande do Norte(UFRN) NatalRNBrazil School of Medicine of the University of Sao Paulo Ribeirao Preto Campus(FMRP/USP)Ribeirao PretoSPBrazil

Background:In Brazil,people still fall ill and die from tuberculosis(TB),and this can be explained by the significant impasse in the equity of distribution of therapeutic resources to the population as a *** aim was to identify geographical areas which have shown progress in terms of equity(of income,schooling and urban occupancy)and test its effect on mortality from TB in a municipality of southeast ***:It is an ecological study considering TB as the basic cause for deaths registered between 2006 and 2013 on the Mortality Information System and other variables obtained through the Demographic Census of the Brazilian Institute of Geography and Statistics(2010).The geographical area for analysis comprised the areas of coverage of the health *** indicators have been constructed through the Principal Component Analysis(PCA).The cases were geocoded and the annual mortality rate from TB was calculated with smoothing using the local empirical Bayesian *** linear regression was then *** was confirmation of the existence of spatial dependence of residue through the application of the Global Moran I test,and application of the Models with Global Spatial Effects,to identify the best standard of spatial ***:The mortality rates ranged from 0.00 to 2.8 deaths per 100,000 people,per *** the PCA,three indicators were constructed,and designated as indicators of income,social inequality,and social *** multiple linear regression,the indicator of social equity was statistically significant(P<0.0001)but had a negative association,an adjusted R^(2)of 28.36%and with spatial dependence(Moran I=0.21,P=0.003455).The best model to deal with existing spatial dependence was the Spatial Lag ***:The better social conditions have shown progress in reducing mortality from TB,thereby reinforcing the achievement of Sustainable Development *** addition,cartography was also applied,which can be replicated

关键词： Tuberculosis Spatial analysis Mortality Cause of death

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运用子带域条纹实现彩色转灰度图的可逆映射

中国印刷与包装研究 2010年第4期2卷 95-96页

作者： ricardo L. de queiroz 李人劼(编译) Departamento de Engenharia Ele trica Universidade de Brasi lia CP 04591 70910-900 Brasi lia DF Brazil 不详

在近年来提出的彩色图像转灰度图的可逆映射概念中指出,彩色图像被映射成条纹后,接收者可用这些条纹通过小波变换、降低采样彩度宽度和重置高频区域的方法来实现彩色图像再现。主要思路是使用黑白打印机打印出带有彩色的图像,然后扫描... 详细信息

在近年来提出的彩色图像转灰度图的可逆映射概念中指出,彩色图像被映射成条纹后,接收者可用这些条纹通过小波变换、降低采样彩度宽度和重置高频区域的方法来实现彩色图像再现。主要思路是使用黑白打印机打印出带有彩色的图像,然后扫描文件并再现彩色。本文提出了一个更为有效地抗打印、扫描噪声的方法,即使用冗余再现彩度,将其嵌入总子带区域转换中的多重子带中,即将彩度分散到不同的子带中。从理论角度证实了为了减小由白色噪声引起的误差方差,彩度应该置于许多子带中,而不是形成线性组合。此外,本文还介绍了寻找最佳线性转换的方法,该方法可以在更普遍的彩色噪声下将彩度嵌入子带中。通过对噪声进行分析确定上限,以指导彩度嵌入子带时所需子带的数量。实验结果均在真实打印和扫描条件下进行,并使用了模拟的打印、扫描路径。

关键词：彩色转灰度可逆彩色映射色彩嵌入子带变换

Assessment of Genetic Stability Among In Vitro Plants of Arachis retusa Using RAPD and AFLP Markers for Germplasm Preservation

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Journal of Integrative Plant Biology 2007年第3期49卷 307-312页

作者： Rachel Fatima Gagliardi Luiz ricardo Hanai Georgia Pacheco Carlos Alberto Oliveira Leonardo Alves Carneiro José Francisco Montenegro Valls Elisabeth Mansur Maria Lucia Carneiro Vieira Laboratório de Micropropagacao e Transformacao de Plantas Universidade do Estado do Rio de Janeiro postal code 20550-013 Maracana Rio de Janeiro Brazil Departamento de Genética - Escola Superior de Agricultura Luiz de queiroz Universidade de Sao Paulo postal code 13418-900 Piracicaba Brazil Embrapa Recursos Genéticos e Biotecnologia postal code 70770-901 Brasilia Brazil

Arachis retusa Krapov. et W. C. Gregory et Valls is endemic in the West-central region of Brazil, occurring In areas endangered by human actions. The establishment of in vitro preservation methods for wild species of Arachis is an alternative to seed banks for germplasm storage, multiplication and distribution. The risk of genetic changes Induced by tissue culture and the monitoring of the genetic stability of the biological material before, during and after storage must be considered In the context of conservation. Random amplified polymorphlc ONA （RAPO） and amplified fragment length polymorphism （AFLP） fingerprinting were used to evaluate the genetic stability of in vitro plants originated from cotyledons and embryo axes of A. retusa. Cotyledons originated shoots through direct organogenesls and embryo axes displayed muItishoot formation Induced by 110 mmol/L and 8.8 mmol/L BAP, respectively. Ninety genomlc regions （loci） generated from RAPO and 372 from AFLP analyses were evaluated. All amplified fragments detected by both techniques in plants derived from the two explant types were monomorphic. The results Indicate that the recovered shoots are genetically stable at the assessed genomic regions.

关键词： amplified fragment length polymorphism Arachis retusa in vitro preservation micropropagation random amplifiedpolymorphic DNA somaclonal variation

基于植物电信号的小麦苗期等渗干旱胁迫与盐胁迫辨识

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农业机械学报 2021年第7期52卷 231-236页

作者：李进海李洋 ricardo Ferraz de Oliveira 姚杰鹏黄岚王忠义中国农业大学信息与电气工程学院北京100083 中国农业大学现代精细农业系统集成研究教育部重点实验室北京100083 中国农业大学农业农村部农业信息获取技术重点实验室北京100083 圣保罗大学路易斯·德奎罗兹农业学院皮拉西卡巴3538709

针对早期干旱胁迫与盐胁迫在植物处于逆境时难以区分的问题,提出一种基于光诱导植物电信号的干旱胁迫与盐胁迫辨识方法。使用光/暗循环刺激获取了小麦幼苗在正常状态以及等渗干旱胁迫与盐胁迫下的植物叶表面电位,并利用一对一分类策略... 详细信息

针对早期干旱胁迫与盐胁迫在植物处于逆境时难以区分的问题,提出一种基于光诱导植物电信号的干旱胁迫与盐胁迫辨识方法。使用光/暗循环刺激获取了小麦幼苗在正常状态以及等渗干旱胁迫与盐胁迫下的植物叶表面电位,并利用一对一分类策略的支持向量机(One-versus-one support vector machine,OVOSVM)对获取的植物电信号样本进行分类。三折交叉验证结果显示:对正常状态与干旱胁迫下小麦幼苗叶表面电位进行二分类,分类准确率达到100%;对正常状态与盐胁迫下小麦幼苗叶表面电位进行二分类,准确率为94.44%;进行三分类时准确率达到96.30%;对等渗干旱胁迫与盐胁迫下获取的小麦叶表面电位进行二分类,分类准确率为100%。研究表明,植物电信号作为一种辨识逆境胁迫的方法,可对等渗条件下早期干旱胁迫与盐胁迫进行准确区分。

关键词：小麦幼苗叶表面电位光诱导植物电信号等渗干旱胁迫与盐胁迫支持向量机

Determining the Levels of Trace Elements Cd, Cu, Pb and Zn in Honey of Stingless Bee (Hymenoptera: Apidae) Using Voltammetry

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Food and Nutrition Sciences 2015年第7期6卷 591-596页

作者： Andreia Santos do Nascimento Luis Carlos Marchini Carlos Alfredo Lopes de Carvalho Diogo Feliciano Dias Araújo Talita Antonia da Silveira ricardo Alves de Olinda Departamento de Entomologia e Acarologia Escola Superior de Agricultura “Luiz de Queiroz” Universidade de S&atilde o Paulo Piracicaba Brazil Centro de Ciências Agrárias Ambientais e Biológicas Universidade Federal do Rec&ocirc ncavo da Bahia Cruz das Almas Brazil Departamento de Estatística Centro de Ciência e Tecnologia Universidade Estadual da Paraíba Bodocongó Brazil

Determining the levels of heavy metals in honey is a measure to control its quality. The objective of this study was to determine the contents of Cd, Cu, Pb and Zn in honey of stingless bee. The differential pulse anodic stripping voltammetry (DPASV) was used to determine the trace elements in honey samples. Pb was detected in 100% of the samples, Cu and Zn in 98.15%, and Cd only in 33.33%. The trace elements analyzed detected in the samples remained within tolerable levels in foods for human consumption.

关键词： Heavy Metals Stingless Bees Voltammetry Honey