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Accuracy Enhancement of the Folin-Ciocalteu Method for Propolis

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American journal of Analytical Chemistry 2024年第8期15卷 253-267页

作者： Rosilene s. N. Paganotti Paulo j. s. Barbeira Instituto Federal de Educao Cincia e Tecnologia de Minas GeraisCampus Formiga Formiga MG Brazil Departamento de Qumica Instituto de Cincias Exatas Universidade Federal de Minas Gerais Belo Horizonte MG Brazil

This study presents an optimization of the Folin-Ciocalteu spectrophotometric method for the determination of total phenol content. Multivariate optimization using factorial planning 22 with a central point and central composite planning was constructed to evaluate the influence of variables in the process and maximize radiation absorption with minimal radiation scattering caused by solid formation. X-ray fluorescence and X-ray diffraction spectrometry were used to evaluate the chemical composition of solids formed and nephelometric and spectrophotometric studies were also used to evaluate whether the type, origin, dilution and dry extract contents of commercial propolis extracts would significantly influence the increase in radiation scattering and absorption. The optimized methodology added several advantages, such as reduction of reagents, time analysis, and higher accuracy.

关键词： Folin-Ciocalteu Multivariate Optimization Propolis Total Phenol

Flow Regimes in Bubble Columns with and without Internals: A Review

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Fluid Dynamics & Materials Processing 2024年第2期20卷 239-256页

作者： Ayat N.Mahmood Amer A.Abdulrahman Laith s.sabri Abbas.j.sultan Hasan shakir Majdi Muthanna H.Al-Dahhan Department of Chemical Engineering University of Technology-IraqBaghdadIraq Chemical and Petroleum Industries Engineering Department Al-Mustaqbal University CollegeBabylonIraq Department of Chemical and Biochemical Engineering Missouri University of Science and TechnologyRollaUSA

Hydrodynamics characterization in terms ofﬂow regime behavior is a crucial task to enhance the design of bubble column reactors and scaling up related *** review presents recent studies on the typicalﬂow regimes established in bubble *** effort is also provided to introduce relevant deﬁnitions pertaining to thisﬁeld,namely,that of“void fraction”and related(local,chordal,cross-sectional and volumetric)*** studies involving different parameters that affect design and operating conditions are also discussed in *** the second part of the review,the attention is shifted to cases with internals of various types(perfo-rated plates,bafﬂes,vibrating helical springs,mixers,and heat exchanger tubes)immersed in the bubble *** is shown that the presence of these elements has a limited inﬂuence on the global column ***,they can make the homogeneousﬂow regime more stable in terms of transition gas velocity and transi-tion holdup *** last section is used to highlight gaps which have not beenﬁlled yet and future directions of investigation.

关键词： Hydrodynamics ﬂow regime bubble column heat-exchanging internals

Photoluminescence enhancement of red-emitting GdVO_4:Eu and YVO_4:Eu phosphors by adding zinc

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journal of Rare Earths 2013年第1期31卷 13-17页

作者： K.Park j.Kim K.Y.Kim j.Y.Kim Y.Kim s.j.dhoble Faculty of Nanotechnology and Advanced Materials Engineering Sejong University Department of Advanced Materials Engineering Hoseo University Department of Chemistry and Institute of Basic sciences Dankook University Department of Physics R.T.M. Nagpur University

We synthesized the rare-earth activated Ro.94_xEuo.06ZnxVO4 （R： Gd and Y; 0〈_x〈_0.08） phosphors with a spherical mor- phology and a smooth surface by the ultrasonic spray pyrolysis. The annealed Ro.94_xEuo.06ZnxVO4 crystallized in the tetragonal zircon type structure, belonging to the space group of I41/amd. The incorporation of a small amount of Zn to Ro.94Euo.06VO4 improved the emission characteristics. The emission intensities of the Gdo.88EUo.06Zno.06VO4 and Yo.9Euo.06Zno.04VO4 phosphors at 619 nm were 72% and 2 1% stronger than those of the Gdo,94Euo.06VO4 and Yo.94Euo.06VO4 phosphors, respectively. We demonstrated that the addi- tion of Zn to Ro.94Euo.06VO4 was quite effective for improving the photoluminescent properties.

关键词： rare earths photolurninescence vanadate ultrasonic spray pyrolysis

Understanding intrarenal backflow: Intrarenal pressure during ureteroscopy and beyond

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Asian journal of Urology 2024年第2期11卷 139-142页

作者： Palle j.s.Osther susanne s.Osther Maria P.Hesselholt sofia Byllov søren K.Lildal Louise F.Øbro Helene jung Urological Research Center Department of UrologyVejle Hospital(a part of Lillebaelt Hospital)University Hospital of Southern DenmarkVejleDenmark Department of Regional Health Research University of Southern DenmarkOdenseDenmark

The number of ureterorenoscopic procedures for upper urinary tract stone management has increased dramatically during recent years worldwide[1].Developments in flexible ureteroscope and laser technology have made it possible to successfully address larger and more complex stone scenarios *** the other hand,this means that more and more patients are exposed to the potential adverse effects of ureteroscopy[2].In general,ureteroscopy is considered a safe ***,serious complications and even deaths do occur,and these events are most likely underreported[3,4].

关键词： beyond likely ureter

sTCF conceptual design report (Volume 1): Physics & detector

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Frontiers of physics 2024年第1期19卷 1-154页

作者： M.Achasov X.C.Ai L.P.An R.Aliberti Q.An X.Z.Bai Y.Bai O.Bakina A.Barnyakov V.Blinov V.Bobrovnikov D.Bodrov A.Bogomyagkov A.Bondar I.Boyko Z.H.Bu F.M.Cai H.Cai j.j.Cao Q.H.Cao X.Cao Z.Cao Q.Chang K.T.Chao D.Y.Chen H.Chen H.X.Chen j.F.Chen K.Chen L.L.Chen P.Chen s.L.Chen s.M.Chen s.Chen s.P.Chen W.Chen X.Chen X.F.Chen X.R.Chen Y.Chen Y.Q.Chen H.Y.Cheng j.Cheng s.Cheng T.G.Cheng j.P.Dai L.Y.Dai X.C.Dai D.Dedovich A.Denig I.Denisenko j.M.Dias D.Z.Ding L.Y.Dong W.H.Dong V.Druzhinin D.s.Du Y.j.Du Z.G.Du L.M.Duan D.Epifanov Y.L.Fan s.s.Fang Z.j.Fang G.Fedotovich C.Q.Feng X.Feng Y.T.Feng j.L.Fu j.Gao Y.N.Gao P.s.Ge C.Q.Geng L.s.Geng A.Gilman L.Gong T.Gong B.Gou W.Gradl j.L.Gu A.Guevara L.C.Gui A.Q.Guo F.K.Guo j.C.Guo j.Guo Y.P.Guo Z.H.Guo A.Guskov K.L.Han L.Han M.Han X.Q.Hao j.B.He s.Q.He X.G.He Y.L.He Z.B.He Z.X.Heng B.L.Hou T.j.Hou Y.R.Hou C.Y.Hu H.M.Hu K.Hu R.j.Hu W.H.Hu X.H.Hu Y.C.Hu j.Hua G.s.Huang j.s.Huang M.Huang Q.Y.Huang W.Q.Huang X.T.Huang X.j.Huang Y.B.Huang Y.s.Huang N.Hüsken V.Ivanov Q.P.ji j.j.jia s.jia Z.K.jia H.B.jiang j.jiang s.Z.jiang j.B.jiao Z.jiao H.j.jing X.L.Kang X.s.Kang B.C.Ke M.Kenzie A.Khoukaz I.Koop E.Kravchenko A.Kuzmin Y.Lei E.Levichev C.H.Li C.Li D.Y.Li F.Li G.Li G.Li H.B.Li H.Li H.N.Li H.j.Li H.L.Li j.M.Li j.Li L.Li L.Li L.Y.Li N.Li P.R.Li R.H.Li s.Li T.Li W.j.Li X.Li X.H.Li X.Q.Li X.H.Li Y.Li Y.Y.Li Z.j.Li H.Liang j.H.Liang Y.T.Liang G.R.Liao L.Z.Liao Y.Liao C.X.Lin D.X.Lin X.s.Lin B.j.Liu C.W.Liu D.Liu F.Liu G.M.Liu H.B.Liu j.Liu j.j.Liu j.B.Liu K.Liu K.Y.Liu K.Liu L.Liu Q.Liu s.B.Liu T.Liu X.Liu Y.W.Liu Y.Liu Y.L.Liu Z.Q.Liu Z.Y.Liu Z.W.Liu I.Logashenko Y.Long C.G.Lu j.X.Lu N.Lu Q.F.Lü Y.Lu Y.Lu Z.Lu P.Lukin F.j.Luo T.Luo X.F.Luo Y.H.Luo H.j.Lyu X.R.Lyu j.P.Ma P.Ma Y.Ma Y.M.Ma F.Maas s.Malde D.Matvienko Z.X.Meng R.Mitchell A.Nefediev Y.Nefedov s.L.Olsen Q.Ouyang P.Pakhlov G.Pakhlova X.Pan Y.Pan E.Passemar Y.P.Pei H.P.Peng L.Peng X.Y.Peng X.j.Peng K.Peters s.Pivovarov E.Pyata B.B.Qi Y.Q.Qi W.B.Qian Y.Qian C.F.Qiao j.j.Qin j.j.Qin L.Q.Qin X.s.Qin T.L.Qiu j.Rademacker C.F.Redmer H.Y.sang Anhui University Hefei 230039China Beihang University Beijing 100191China Budker Institute of Nuclear Physics Novosibirsk 630090Russia CAs Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Cavendish Laboratory University of CambridgeJJ Thomson AveCambridge CB30HEUnited Kingdom Central China Normal University Wuhan 430079China Central south University Changsha 410083China China University of Geosciences Wuhan 430074China China University of Mining and Technology Xuzhou 221116China École Polytechnique Fédérale de Lausanne(EPFL) LausanneSwitzerland Fudan University Shanghai 200433China Goethe University Frankfurt D-60325 Frankfurt am MainGermany Guangxi Normal University Guilin 541004China Guangxi Uninversity Nanning 530004China Hangzhou Institute for Advanced study UCASHangzhou 310024China Hebei Normal University Shijiazhuang 050024China Hebei University Baoding 071002China Hefei University of Technology Hefei 230601China Helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany Henan Normal University Xinxiang 453007China Henan University Kaifeng 475004China High Energy Physics Center Chung-Ang UniversitySeoul 06974Korea Higher school of Economy 11 Pokrovsky Bulvar Moscow 109028Russia Huangshan University Huangshan 245000China Hubei University of Automotive Technology Shiyan 442002China Hunan Normal University Changsha 410081China Hunan University of science and Technology Xiangtan 411201China Hunan University Changsha 410082China Indiana University BloomingtonIndiana 47405USA Inner Mongolia University Hohhot 010021China Institute of Advanced science Facilities Shenzhen 518107China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Institute of Physics Academia SinicaTaipeiTaiwan 11529China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China jilin University Changch

The superτ-charm facility(sTCF)is an electron–positron collider proposed by the Chinese particle physics *** is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or *** sTCF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEPCII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the standard *** sTCF project in China is under development with an extensive R&D *** document presents the physics opportunities at the sTCF,describes conceptual designs of the sTCF detector system,and discusses future plans for detector R&D and physics case studies.

关键词： electron–positron collider tau-charm region high luminosity sTCF detector conceptual design

A study of the Comets with Large Perihelion Distances C/2019 L3(ATLAs)and C/2019 O3(Palomar)

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Research in Astronomy and Astrophysics 2024年第9期24卷 199-213页

作者： Alberto s.Betzler Centro de Ciencia e Tecnologia em Energia e sustentabilidade Universidade Federal do Recôncavo da BahiaFeira de SantanaBahia44.085-132Brazil

This work analyzes the photometric data of the Oort spike comets C/2019 L3(ATLAs)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the ATLAs network and the Belgian Olmen *** comets Palomar and ATLAs have a typical and unusually high activity level,respectively,based on the Afρparameter corrected to phase angle zero at *** absolute magnitude of comets ATLAs and Palomar in the o-band is 4.71±0.05 and 4.16±0.02 *** cometary activity of comets ATLAs and Palomar probably began at r>13 au before perihelion and will end at r>14 au after perihelion,which means that they could remain active until the second half of *** nucleus of comet ATLAs has a minimum radius of 7.9 km,and the nucleus of comet Palomar could be a little *** c-o colors of the comets ATLAs and Palomar are redder and bluer,respectively,at perihelion than the solar twin YBP *** comets showed a bluish trend in the coma color with decreasing heliocentric *** Palomar probably had two outbursts after its perihelion,each releasing about 10^(8)kg of *** slopes of the photometric profile of the comae of these comets were between 1and 1.5,indicating a steady state during the observation campaign.

关键词： individual C/2019 L3(ATLAs) C/2019 O3(Palomar) techniques:photometric methods:data analysis

Enhancing Ulcerative Colitis Diagnosis:A Multi-Level Classification Approach with Deep Learning

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Computer Modeling in Engineering & sciences 2024年第7期140卷 1129-1142页

作者： Hasan j.Alyamani Department of Information systems Faculty of Computing and Information Technology in RabighKing Abdulaziz UniversityJeddah21589Saudi Arabia

The evaluation of disease severity through endoscopy is pivotal in managing patients with ulcerative colitis,a condition with significant clinical ***,endoscopic assessment is susceptible to inherent variations,both within and between observers,compromising the reliability of individual *** study addresses this challenge by harnessing deep learning to develop a robust model capable of discerning discrete levels of endoscopic disease *** initiate this endeavor,a multi-faceted approach is embarked *** dataset is meticulously preprocessed,enhancing the quality and discriminative features of the images through contrast limited adaptive histogram equalization(CLAHE).A diverse array of data augmentation techniques,encompassing various geometric transformations,is leveraged to fortify the dataset’s diversity and facilitate effective feature extraction.A fundamental aspect of the approach involves the strategic incorporation of transfer learning principles,harnessing a modified ResNet-50 *** augmentation,informed by domain expertise,contributed significantly to enhancing the model’s classification *** outcome of this research endeavor yielded a highly promising model,demonstrating an accuracy rate of 86.85%,coupled with a recall rate of 82.11%and a precision rate of 89.23%.

关键词： Ulcerative colitis deep learning CLAHE transfer learning geometric transformations

Physiological and perceptual responses to sprint interval exercise using arm versus leg cycling ergometry

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sports Medicine and Health science 2024年第4期6卷 385-393页

作者： Todd A.Astorino shealin Pierce Madisen B.Piva Richard s.Metcalfe Niels B.j.Vollaard Department of Kinesiology CSU—San MarcosSan MarcosCAUSA Applied sports TechnologyExercise and Medicine(A-STEM)Research CenterSwansea UniversitySwanseaUK Faculty of Health sciences and sport University of StirlingStirlingUK

Increases in power output and maximal oxygen consumption(V_O2max)occur in response to sprint interval exercise(sIE),but common use of“all-out”intensities presents a barrier for many ***,lower-body sIE is not feasible for all *** compared physiological and perceptual responses to supramaximal,but“nonall-out”sIE between leg and arm cycling ***-four active adults(mean±sD age:[25±7]y;cycling VO_(2)max:[39±7]mL·kg^(-1)·min^(-1))performed incremental exercise using leg(LCE)and arm cycle ergometry(ACE)to determine VO_(2)max and maximal work capacity(Wmax).subsequently,they performed four 20 s bouts of sIE at 130% Wmax on the LCE or ACE at cadence=120-130 rev/min,with 2 min recovery between *** exchange data,heart rate(HR),blood lactate concentration(BLa),rating of perceived exertion(RPE),and affective valence were *** showed significantly lower(psolute mean([1.24±0.31]L·min^(-1) vs.[1.59±0.34]L·min^(-1);d=1.08)and peak VO_(2)([1.79±0.48]L·min^(-1) vs.[2.10±0.44]L·min^(-1);d=0.70)with ACE versus ***,ACE elicited significantly higher(ps.[57%±7%]VO_(2)max,d=0.63)and peak VO_(2)([88%±10%]VO_(2)max vs.[75%±10%]VO_(2)max,d?1.33).Post-exercise BLa was significantly higher([7.0±1.7]mM vs.[5.7±1.5]mM,p=0.024,d?0.83)for LCE versus *** was no significant effect of modality on RPE or affective valence(p>0.42),and lowest affective valence recorded(2.0±1.8)was considered“good to fairly good”.Data show that non“all-out”ACE elicits lower absolute but higher relative HR and VO_(2) compared to *** aversive perceptual responses could make this non-all-out modality feasible for inactive adults.

关键词： High intensity interval training Upper body exercise Peak power output Oxygen uptake Blood lactate concentration

Intelligent Machine Learning Based Brain Tumor segmentation through Multi-Layer Hybrid U-Net with CNN Feature Integration

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Computers, Materials & Continua 2024年第4期79卷 1301-1317页

作者： sharaf j.Malebary Department of Information Technology Faculty of Computing and Information TechnologyKing Abdulaziz UniversityP.O.Box 344Rabigh21911Saudia Arabia

Brain tumors are a pressing public health concern, characterized by their high mortality and morbidity ***, the manual segmentation of brain tumors remains a laborious and error-prone task, necessitatingthe development of more precise and efficient methodologies. To address this formidable challenge, we proposean advanced approach for segmenting brain tumorMagnetic Resonance Imaging (MRI) images that harnesses theformidable capabilities of deep learning and convolutional neural networks (CNNs). While CNN-based methodshave displayed promise in the realm of brain tumor segmentation, the intricate nature of these tumors, markedby irregular shapes, varying sizes, uneven distribution, and limited available data, poses substantial obstacles toachieving accurate semantic segmentation. In our study, we introduce a pioneering Hybrid U-Net framework thatseamlessly integrates the U-Net and CNN architectures to surmount these challenges. Our proposed approachencompasses preprocessing steps that enhance image visualization, a customized layered U-Net model tailoredfor precise segmentation, and the inclusion of dropout layers to mitigate overfitting during the training ***, we leverage the CNN mechanism to exploit contextual information within brain tumorMRI images,resulting in a substantial enhancement in segmentation *** experimental results attest to the exceptionalperformance of our framework, with accuracy rates surpassing 97% across diverse datasets, showcasing therobustness and effectiveness of our approach. Furthermore, we conduct a comprehensive assessment of ourmethod’s capabilities by evaluating various performance measures, including the sensitivity, jaccard-index, andspecificity. Our proposed model achieved 99% accuracy. The implications of our findings are profound. Theproposed Hybrid U-Net model emerges as a highly promising diagnostic tool, poised to revolutionize brain tumorimage segmentation for radiologists and clinician

关键词： Brain tumor Hybrid U-Net CLAHE transfer learning MRI images