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Synthesis of highly fluorescent carbon dots from lemon and onion juices for determination of riboflavin in multivitamin/mineral supplements

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Journal of Pharmaceutical Analysis 2019年第3期9卷 209-216页

作者： Severino S. Monte-Filho Stefani I.E. Andrade Marcelo B. lima Mario c.U. araujo Universidade Federal da Paraíba CCEN Departamento de Química P.O. Box 5093 Zip Code 58051-970 Joao Pessoa PB Brazil Universidade Federal Rural de Pernambuco-Unidade Acad^emica de Serra Talhada UAST Zip Code 56909-535 Serra Talhada PE Brazil

In this work, lemon and onion biomasses commonly found in street markets are for the first time used to develop a facile, fast and low-cost one-step microwave-assisted carbonization method for synthesis of highly fluorescent carbon dots (cDs). The structure and optical properties of cDs were investigated by TEM, XRD, XRF, UV-Vis, FTIR, and fluorescence spectroscopy. cDs displayed satisfactory optical pro-prieties, a high quantum yield of 23.6%, and excellent water solubility, and the particle size was 4.23-8.22 nm with an average diameter of 6.15 nm. An efficient fluorescent resonance energy transfer (FRET) between the cDs and riboflavin was achieved with cDs acting as donor and riboflavin as acceptor. A linear relationship between FRET and the riboflavin concentration from 0.10 to 3.0 μg/ml was observed, allowing the development of an accurate and fast analytical method to determine this vitamin in multivitamin/mineral supplements. Despite the potential interferences in these supplements, cDs were selective for riboflavin under optimized conditions. A paired t-test at a 95% confidence level indicated no statistically significant difference between the proposed and the reference methods. Recovery test presented values ranged from 96.0% to 101.4%. The limit of detection and relative standard deviation were estimated at 1.0 ng/ml and ctively. cDs were successfully synthesized in a domestic microwave oven (1450 W, 6 min), presenting satisfactory parameters when compared with results of other studies reported in the literature, suggesting that the proposed method is a potentially useful method for the synthesis of cDs and determination of riboflavin.

关键词： carbon dots Microwave-assisted carbonization lemon-onion juice Riboflavin Multivitamin/mineral supplements Fluorescence

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Brain tumor surgery:supplemental intra-operative imaging techniques and future challenges

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Journal of cancer Metastasis and Treatment 2016年第1期2卷 70-79页

作者： Telmo Augusto Barba Belsuzarri raphael Martinelli Anson Sangenis João Flavio Mattos araujo Department of Neurosurgery Pontifical Catholic University of CampinasCampinasSão Paulo 13060-803Brazil

Modern brain tumor surgery stands in the pillar of maximum safe *** borders are always challenging,especially infiltration zones in malignant brain *** technologies are designed for a better delineation and to increase the extent of resection(EOR)in brain tumor surgery,such as:cortical and sub-cortical mapping strategies with somatosensory-evoked potentials,awake stimulation mapping and cortical/sub-cortical stimulation for motor pathways,important for resection in eloquent areas;intra-operative imaging as functional and intra-operative magnetic resonance imaging,diffusion tensor imaging and intra-operative ultrasound are important for the tumor borders and to achieve the gross total resection;neurochemical navigation methods as 5-aminolevulinic and sodium fluorescein are important for the non-contrast-enhanced tumor border;future methods can be achieved with augmented reality surgery,new intra-operative chemical markers,and visualization *** all these techniques seem to be promising,the real challenge in the future will be held in how to apply them and how they really affect the prognosis of the ***,new concepts in tumor genetics will provide knowledge for the tumor behavior and will guide *** all limitations,the increasing importance of safe EOR shows the possible benefits of the novel technologies and surgical advances in brain tumor surgery,taking it to a new step of the neuronavigation era.

关键词： Brain tumor fluorescein intra-operative neuronavigation novel technology

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Analysis of Short-Term Metabolic Alterations in Arabidopsis Following changes in the Prevailing Environmental conditions

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Molecular Plant 2014年第5期7卷 893-911页

作者： Alexandra Florian Zoran Nikoloski Ronan Sulpice Stefan Timm Wagner l. araujo Takayuki Tohge Hermann Bauwe Alisdair R. Fernie Max-Planck-Institut for Molekulare Pflanzenphysiologie Am Muhlenberg 1 14476 Potsdam-Golm Germany NUIG Plant Systems Biology Lab Plant and AgriBiosciences Research Centre Botany and Plant Science Galway Ireland Department of Plant Physiology University of Rostock D-18059 Rostock Germany Departamento de Biologia Vegetal Universidade Federal de Vicosa 36570-000 Vicosa Minas Gerais Brazil

Although a considerable increase in our knowledge concerning the importance of metabolic adjustments to unfavorable growth conditions has been recently provided, relatively little is known about the adjustments which occur in response to fluctuation in environmental factors. Evaluating the metabolic adjustments occurring under changing environmental conditions thus offers a good opportunity to increase our current understanding of the crosstalk between the major pathways which are affected by such conditions. To this end, plants growing under normal conditions were transferred to different light and temperature conditions which were anticipated to affect （amongst other processes） the rates of photosynthesis and photorespiration and characterized at the physiological, molecular, and metabolic levels following this transition. Our results revealed similar behavior in response to both treatments and imply a tight connec- tivity of photorespiration with the major pathways of plant metabolism. They further highlight that the majority of the regulation of these pathways is not mediated at the level of transcription but that leaf metabolism is rather pre-poised to adapt to changes in these input parameters.

关键词： central metabolism environmental perturbation gene expression metabolic regulation photorespiration photosynthesis ribulose-1,5-bisphosphate carboxylase/oxygenase (RubiscO).

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contribution of inrush current to mechanical failure of power transformers windings

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High Voltage 2019年第4期4卷 300-307页

作者： Rafael M.R.Barros Edson Gda costa Jalberth F.araujo Filipe l.Mde Andrade Tarso V.Ferreira Department of Electrical Engineering Federal University of Campina GrandeAprigio Veloso St.882Campina GrandeBrazil

This work presents a study regarding the contribution of inrush current to the occurrence of mechanical fatigue in windings of a power transformer and,consequently,the impact of that phenomenon on the equipment's *** order to perform the study,electromagnetic transient simulations were used to determine the inrush current in a three-phase transformer ***,three-dimensional simulations,based on the finite element method,were performed to determine the electromechanical stresses in the equipment windings,under the effect of the inrush ***,the methods of critical plans and Palmgren–Miner were applied to perform the fatigue *** the results,the impact of inrush current on the integrity of the transformer's windings was determined,as well as,to estimate the reduction of lifespan of the equipment due to inrush *** number of inrushes needed for the total reduction of lifespan of the equipment due to mechanical fatigue was also *** results can be used in the transformers design stage,with the purpose of assisting the evaluation of mechanical withstand of equipment,which can minimise the possibility of failure and increase its lifespan.

关键词： winding fatigue power

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Engineering Improved Photosynthesis in the Era of Synthetic Biology

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Plant communications 2020年第2期1卷 1-17页

作者： Willian Batista-Silva Paula da Fonseca-Pereira Auxiliadora Oliveira Martins Agustin Zsogon Adriano Nunes-Nesi Wagner l.araujo Departamento de Biologia Vegetal Universidade Federal de Vic¸osaVic¸osaMinas Gerais 36570-900Brazil

Much attention has been given to the enhancement of photosynthesis as a strategy for the optimization of crop *** traditional plant breeding is most likely reaching a plateau,there is a timely need to accelerate improvements in photosynthetic efficiency by means of novel tools and biotechnological *** emerging field of synthetic biology offers the potential for building completely novel pathways in predictable directions and,thus,addresses the global requirements for higher yields expected to occur in the 21st ***,we discuss recent advances and current challenges of engineering improved photosynthesis in the era of synthetic biology toward optimized utilization of solar energy and carbon sources to optimize the production of food,fiber,and fuel.

关键词： photosynthesis synthetic biology genetic engineering yield improvement targeted manipulation

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Effects of Flexible conjugation-Break Spacers of Non-conjugated Polymer Acceptors on Photovoltaic and Mechanical Properties of All-Polymer Solar cells

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Nano-Micro letters 2022年第10期14卷 164-177页

作者： Qiaonan chen Yung Hee Han leandro R.Franco cleber F.N.Marchiori Zewdneh Genene cMoyses araujo Jin-Woo lee Tan Ngoc-lan Phan Jingnan Wu Donghong Yu Dong Jun Kim Taek-Soo Kim lintao Hou Bumjoon J.Kim Ergang Wang Siyuan laboratory Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy MaterialsDepartment of PhysicsJinan UniversityGuangzhou 510632People’s Republic of China Department of chemistry and chemical Engineering Chalmers University of TechnologySE-41296GöteborgSweden Department of chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea Department of Engineering and Physics Karlstad University65188 KarlstadSweden Department of chemistry and Bioscience Aalborg University9220 AalborgDenmark Department of Mechanical Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea Materials Theory Division Department of Physics and AstronomyUppsala University75120 UppsalaSweden Sino-Danish center for Education and Research 8000 AarhusDenmark School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001People’s Republic of China

All-polymer solar cells(all-PScs)possess attractive merits including superior thermal stability and mechanical flexibility for large-area roll-to-roll *** flexible conjugation-break spacers(FcBSs)into backbones of polymer donor(P_(D))or polymer acceptor(P_(A))has been demonstrated as an efficient approach to enhance both the photovoltaic(PV)and mechanical properties of the ***,length dependency of FcBS on certain all-PSc related properties has not been systematically *** this regard,we report a series of new non-conjugated P_(A)s by incorporating FcBS with various lengths(2,4,and 8 carbon atoms in thioalkyl segments).Unlike com-mon studies on so-called side-chain engineering,where longer side chains would lead to better solubility of those resulting polymers,in this work,we observe that the solubilities and the resulting photovoltaic/mechanical properties are optimized by a proper FcBS length(i.e.,c2)in P_(A) named *** all-PSc achieves a high efficiency of 11.37%,and excellent mechanical robustness with a crack onset strain of 12.39%,significantly superior to those of the other P_(A)*** results firstly demonstrate the effects of FcBS lengths on the PV performance and mechanical properties of the all-PScs,providing an effective strategy to fine-tune the structures of P_(A)s for highly efficient and mechanically robust PScs.

关键词： All-polymer solar cells Flexible conjugation-break spacers Mechanical robustness Polymer acceptors Stretchability

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Effects of phosphorus fertilizer application on phosphorus fractions in different organs of cordia trichotoma

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Journal of Forestry Research 2021年第2期32卷 725-732页

作者： Matheus S.S.Kulmann lincon O.S.Stefanello RaíA.Schwalbert Álvaro l.P.Berghetti Maristela M.araujo Rogerio Piccin luciano c.Gatiboni Tales Tiecher Paulo A.A.Ferreira Gustavo Brunetto Department of Soil Science Federal University of Santa MariaSanta MariaRio Grande do SulBrazil Department of Rural Engineering Federal University of Santa MariaSanta MariaRio Grande do SulBrazil Department of Forest Engineering Federal University of Santa MariaSanta MariaRio Grande do Sul 97105-900Brazil Agroveterinary Science center State University of Santa CatarinaLagesSanta Catarina88520-000Brazil Department of Soil Science Federal University of Rio Grande do SulPorto AlegreRio Grande do Sul 91540-000Brazil

The application of phosphorus(P)to soil can increase its availability to plants and alter P fractions in annual and perennial organs of cordia *** a portion of P accumulates in perennial organs in organic fractions it can be used in the next growth season,possibly decreasing plant dependence on P derived from soil ***,if P is preferentially accumulated in inorganic fractions in annual organs,plants will be more dependent on phosphate *** study aimed to evaluate the distribution of P fractions in organs of *** grown on sandy soil treated with 120 and 360 kg P2O5 ha^(−1).The control was a zero *** 24 months following fertilization,*** seedlings were cut and separated into leaves,branches,stems and roots,dried,ground and subjected to chemical fractionation of P,which estimates fractions of total soluble P,soluble inorganic and organic P,lipid P,P associated ribonucleic acid and deoxyribonucleic acid,and residual P.P in annual organs,as leaves,accumulated preferentially in the soluble inorganic fraction in both *** perennial organs such as stems and branches,P accumulated preferentially in the soluble organic *** application of 300%of the recommended dosage(360 kg P2O5 ha^(−1))promoted the accumulation of P in soluble organic fractions which may contribute to annual growth the following season and be a strategy to reduce the dependence of 2-year-old stands on soil-derived P and on fertilizers.

关键词： chemical fractionation Phosphorus Phosphate fertilization Plant phosphorus

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硅线性升温快速热处理氧化动力学模型

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Journal of Semiconductors 1991年第11期12卷 666-672页

作者：汤庭鳌 c.A.Paz de araujo 复旦大学电子工程系上海200433 University of colorado at colorado Springs U.s.A.

本文采用玻尔兹曼-曼特诺变换方法,得到了一个新的描述硅快速热氧化生长动力学的解析模型.在靠近硅与二氧化硅界面处产生一个富氧区.在非稳态情况下,直接从氧扩散方程得到了增强因子.在温度为1050—1200℃范围内,本解析模型在计算快速... 详细信息

本文采用玻尔兹曼-曼特诺变换方法,得到了一个新的描述硅快速热氧化生长动力学的解析模型.在靠近硅与二氧化硅界面处产生一个富氧区.在非稳态情况下,直接从氧扩散方程得到了增强因子.在温度为1050—1200℃范围内,本解析模型在计算快速热氧化(RTO)生长的氧化层厚度方面与测量结果基本一致.

关键词：硅氧化动力学热处理模型

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Novel nanocomposites based on a strawberry-like gold-coated magnetite （Fe@Au） for protein separation in multiple myeloma serum samples

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Nano Research 2015年第4期8卷 1189-1198页

作者： Jose E. araujo carlos lodeiro Jose l. capelo Benito Rodrfguez-Gonzalez Alcindo A. dos Santos~ Hugo M. Santos Javier Ferna.ndez-lodeiro BIOScOPE Research Group UCIBIO-REQUIMTE Department of Chemistry Faculty of Science and Technology University NOVA of Lisbon 2829-516 Caparica Portugal PROTEOMASS Scientific Society Madan Parque Rua dos Inventores 2825-182 Caparica Portuga Scientific and Technological Research Assistance centre (cAcTI) University of Vigo Vigo Spain Instituto de Quimica Universidade de Sao Paulo Av. Prof. Lineu Prestes 748 CxP 26077 Sao Paulo 05508-000 Brazil

在水的媒介生产与像草莓的金 nanoparticles 部分涂的磁铁矿的一个新过程被报导。对磁场和金基于 nanoparticle 的胶体的系统的光性质的快反应是这新 Fe@Au nanomaterial 的二个主要优点。这些优点允许为在 proteomics 和 biomedicine ... 详细信息

在水的媒介生产与像草莓的金 nanoparticles 部分涂的磁铁矿的一个新过程被报导。对磁场和金基于 nanoparticle 的胶体的系统的光性质的快反应是这新 Fe@Au nanomaterial 的二个主要优点。这些优点允许为在 proteomics 和 biomedicine 的各种各样的目的这新胶体的 nanomaterial 的使用当蛋白质能也绑在表面，和表面罐头，是 functionalized。作为 proof-of-concept，新 Fe@Au nanoparticles 为蛋白质的集中前和分离作为一个工具在 biomarker 发现被估计了从复杂 proteomes。到这个目的，从健康的人的 sera 与从与多重骨髓瘤诊断的病人的 sera 相比。与集体 spectrometry 相结合的这新 Fe@Au nanomaterial 的应用程序允许 53 的鉴定蛋白质，和它也证明了热吃惊蛋白质 HSP75 和血浆朊酶 c1 禁止者是为多重骨髓瘤前进的诊断和控制的潜在的 biomarkers。

关键词：蛋白质分离多发性骨髓瘤血清样品磁铁矿纳米复合材料镀金草莓金纳米粒子

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Influence of age in estimating maximal oxygen uptake

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Journal of Geriatric cardiology 2016年第2期13卷 126-131页

作者： christina G de Souza Silva Barry A Franklin Daniel E Forman claudio Gil S araujo Heart Institute Edson Saad and Medical School Federal University of Rio de Janeiro Rio de Janeiro R J Brazil Exercise Medicine clinic CLINIMEX Rio de Janeiro R J Brazil Preventive cardiology and cardiac Rehabilitation William Beaumont Hospital Royal Oak MI United States Section of Geriatric cardiology University of Pittsburgh Medical Center Geriatrics Research Education and Clinical Center System University of Pittsburgh Pittsburgh PA USA

ObjectiveTo 在最大的氧举起的估计( EE )的错误上估计年龄的影响( VO 2最大)用性别和在自从估计，测试的周期测力计锻练特定方程的人口， VO 2最大与实质的 EE 被联系，经常超过20%， 18～91 年，可能，由于机械 ***1850 的内在的可... 详细信息

ObjectiveTo 在最大的氧举起的估计( EE )的错误上估计年龄的影响( VO 2最大)用性别和在自从估计，测试的周期测力计锻练特定方程的人口， VO 2最大与实质的 EE 被联系，经常超过20%， 18～91 年，可能，由于机械 ***1850 的内在的可变性，成年人(68%人)经历了最大的周期测力计测试的心肺的锻练。心和肺的健康(cRF ) 相对性别和年龄被估计[更年轻(18 ～ 35 年) ，中年(36 ～ 60 年) 并且更旧(>；60 年)] 。VO 2 最大[ml·；(kg·； min )−1] 被对煤气的交换的评价直接测量并且估计了使用性别和人口特定方程。VO 2 最大和相关 EE 在三年龄特定、性特定的 *** 测量的 VO 2 男人和女人的最大是 29.5 ±；10.5 ml·；(kg·； min )−1 和 24.2 ±；9.0 ml·；(kg·； min )−1(P <；0.01 ) 。EE [ml·；(kg·； min ) 为男人和女人的 −1] 和百分比错误(% E ) 有类似的价值， 0.5 ±；3.2 和 0.4 ±；2.9 ml·；(kg·； min )−1, 和 −； 0.8 ±；13.1% 并且 −； 1.7 ±；15.4%(P >；0.05 ) 分别地。分别地，为每个年龄组的 EE 和 % E 为男人：更年轻的 = 1.9 ±；4.1 ml·；(kg·； min )−1 和 3.8 ±；10.5% ，中年的 = 0.6 ±；3.1 ml·；(kg·； min )−1 和 0.4 ±；10.3% ，更旧的 =−； 0.2 ±；2.7 ml·；(kg·； min )−1 和 −； 4.2 ±；16.6%(P <；0.01 ) ；并且为女人：更年轻的 = 1.2 ±；3.1 ml·；(kg·； min )−1 和 2.7 ±；10.0% ，中年的 = 0.7 ±；2.8 ml·；(kg·； min )−1 和 0.5 ±；11.1% ，更旧的 =-0.8 ±；2.3 ml·；(kg·； min )−1 和 −； 9.5 ±；22.4%(P <；0.01 ).conclusionVO 2 最大在更年轻的年龄组被低估并且在老年组被过高估计。年龄显著地影响 VO 2 在男人和女人的最大并且当 cRF 用人口被估计时，应该被认为特定方程，而非直接测量了。

关键词：最大摄氧量年龄组估计误差直接测量估算自行车运动运动试验机械效率

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