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Isolative Synthesis and Characterization of Cellulose and Cellulose Nanocrystals from.Typha angustifolia

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Open Journal of Applied Sciences 2024年第9期14卷 2443-2459页

作者： Lynda S. m.soppirr evans K. Suter Wesley N. Om.oyo Nathan m. Oyaro Sim.hiwe m. Nelana Departm.nt of m.them.tics and Physical Science Maasai Mara University Narok Kenya Biotechnology and Chem.stry Departm.nt Vaal University of Technology Vanderbijlpark South Africa

The application potential of cellulosic m.terials in natural com.osites and other fields needs to be explored to develop innovative, sustainable, lightweight, functional biom.ss m.terials that are also environm.ntally friendly. This study investigated Typha angustifolia (Typha sp.) as a potential new raw m.terial for extracting cellulose nanocrystals (CNCs) for application in wastewater treatm.nt com.osites. Alkaline treatm.nts and bleaching were used to rem.ve cellulose from.the stem.fibres. The CNCs were then isolated from.the recovered cellulose using acid hydrolysis. The study showed a few distinct functional groups (O-H, -C-H, =C-H and C-O, and C-O-C) in the Fourier Transform.Infrared (FTIR) spectra. A scanning electron m.croscope (SEm. revealed the sm.oth surface of CPC and CNCs, which resulted from.rem.ving lignin and hem.cellulose from.powdered Typha angustifolia. Based on the crystalline index, the powdered Typha angustifolia, CPC, and CNCs were 42.86%, 66.94% and 77.41%. The loss of the am.rphous section of the Typha sp. fibre resulted in a decrease in particle size. It m.y be inferred from.the features of a Typha sp. CNC that CNCs m.y be em.loyed as reinforcem.nt in com.osites for wastewater treatm.nt.

关键词： Typha angustifolia Cellulose Acid Hydrolysis Chem.cally Purified Cellulose Cellulose Nanocrystals

Electrophysiological assessm.nt of prim.ry cortical neurons genetically engineered using iron oxide nanoparticles

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Nano Research 2017年第8期10卷 2881-2890页

作者： m.chael G. evans Arwa Al-Shakli Stuart I. Jenkins Divya m. Chari School of Life Sciences Keele University Keele Staffordshire ST5 5BG UK Institute for Science and Technology in m.dicine Keele University Keele Staffordshire ST5 5BG UK

The developm.nt of safe technologies to genetically m.dify neurons is of great interest in regenerative neurology, for both translational and basic science applications. Such approaches have conventionally been heavily reliant on viral transduction m.thods, which have safety and production lim.tations. m.gnetofection （m.gnet-assisted gene transfer using iron oxide nanoparticles as vectors） has em.rged as a highly prom.sing non-viral alternative for safe and reproducible genetic m.dification of neurons. Despite the high potential of this technology, there is an im.ortant gap in our knowledge of the safety of this approach, nam.ly, whether it alters neuronal function in adverse ways, such as by altering neuronal excitability and signaling. We have investigated the effects of m.gnetofection in prim.ry cortical neurons by exam.ning neuronal excitability using the whole cell patch clam. technique. We found no evidence that m.gnetofection alters the voltage-dependent sodium.and potassium.ionic currents that underpin excitability. Our study provides im.ortant new data supporting m.gnetofection as a safe technology for bioengineering of neuronal cell populations.

关键词： transfection m.gnetic nanoparticle green fluorescent protein (GFP) whole-cell patch clam. fluorescence m.croscopy

Effect of baffles on perform.nce of fluid catalytic cracking riser

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Particuology 2018年第3期16卷 18-30页

作者： m.linkum.r T. Shah Vishnu K. Pareek Geoffrey m. evans Ranjeet P. Utikar Departm.nt of Chem.cal Engineering Curtin University Western Australia Australia Departm.nt of Chem.cal Engineering University of Newcastle New South Wales Australia

Increasing dem.nd of autom.bile fuel and a need to process heavier crude oil m.kes it im.erative to find im.rovem.nts to the design of existing fluid catalytic cracking （FCC） units. Several m.difications to the design of the riser section of FCC units have been suggested in previous studies including： im.roved feed nozzle designs, m.ltiple nozzle configurations, internal baffles, and novel two-stage-riser system.. In this study, we investigate the effects of baffles on the perform.nce of FCC risers using com.utational fluid dynam.cs sim.lations. In this study, predictions from.a basis m.del （without baffles） are com.ared with those from.four different configurations including：（i） 5-cm.baffles at 5-m.spacing, （ii） 7.5-cm.baffles at 5- m.spacing, （iii） 10-cm.baffles with 5-m.spacing, （iv） lO-cm.baffles at 2.5-m.spacing, and （v） lO-cm.baffles at 1-m.spacing. The baffles force the catalyst away from.wails toward the center of the riser, enhancing the radial dispersion of the catalyst and the heat transfer inside the riser. The use of longer baffles and sm.ller spacings further increases the dispersion, yielding m.re hom.geneous radial profiles. The changes in the radial dispersion result in variations in the conversion, yields, and pressure drops. The baffles increase conversion of vacuum.gas oil （VGO） and the yield of gasoline. However, the sim.lations showed that longer baffles and a larger num.er of baffles did not always give a higher yield or higher conversion. Am.ng the sim.lated configurations, the 5-cm.baffles at 5-m.spacing gave the highest conversion of VGO, whereas the 10-cm.baffles at 1 -m.spacing resulted in the highest yield of the gasoline. Thus, rational optim.zation of baffle configurations is required to achieve optim.l perform.nce.

关键词： Fluid catalytic cracking Riser Baffles Com.utational fluid dynam.cs

Sedim.ntary Environm.nts, Geom.try and Characteristics of the Sand Layers within the Basin of El m. Labiod （Algero-Tunisian Borders）

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Journal of Environm.ntal Science and Engineering 2011年第12期5卷 1617-1623页

作者： m. Ham.m.d m. EI Kadi m. AI shara Departm.nt of Geology Faculty of Exact Natural and Life Sciences University of Tebessa Tebessa 12002 Algeria Departm.nt of Geology Faculty of Sciences University of Damascus Damascus 12345 Syria

The authors＇ work concerns the study of sedim.ntary environm.nts, the geom.try and the characteristics of the silicon-clastic deposits within the basin of EI m. Labiod at the Algero-Tunisian confines. The sedim.ntological analysis has proved a m.ocene age of the sedim.nts with varied environm.nts： m.rine, fluvial-deltaic and lake. The geological aspect of the sedim.nt, in particular sandy, is of the m.vable type or very slightly consolidated. The size of the industrial sand layers can be very diverse, however to feed from.the industrial consum.rs having a certain perenniality, our prospection was directed towards layers with very im.ortant reserves. It is about a sedim.ntary basin with dim.nsions exceeding very largely the conditions of operating for such projects, which are at least one to two m.llion tons. With the exception of a thin quaternary soil horizon, the basin is alm.st of an exploitation with open sky. The m.neralogical determ.nation has revealed siliceous to extra-siliceous sands, which are absolutely usable in the industry of glass, foundry and also in other functions like the abrasives of sanding and the clothing industry of the sandpapers. Concerning the econom.c aspect, the m.terials are very close and this is why the area has known the installation of a glassm.king factory and a cem.nt factory using at the sam. tim. the m.astrichtian lim.stone, the sandy m.terial and the clays of the Western zone of the basin.

关键词： m.ocene El m. Labiod basin sedim.ntary environm.nts m.neralogy petrography econom.c aspects.

Evolving Fram.works for the Foundation and Practice of Electronic Fetal m.nitoring

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m.ternal-Fetal m.dicine 2022年第2期4卷 141-151页

作者： m.rk I.evans David W.Britt shara m.evans Lawrence D.Devoe Fetal m.dicine Foundation of Am.rica New YorkNY 10065USA Com.rehensive Genetics PLLCNew YorkNY 10065USA Departm.nt of Obstetrics&Gynecology Icahn School of Medicine at Mt.SinaiNew YorkNY10029USA Departm.nt of m.ternal Child Health Gillings School of Public Health University of North Carolina at Chapel HillChapel HillNY 27599USA Departm.nt of Obstetrics and Gynecology Medical College of GeorgiaAugusta UniversityAugustaGA 30907USA.

Since the 1970s,electronic fetal m.nitoring(EFm.also known as cardiotocography(CTG)has been used extensively in labor around the world,despite its known failure to help prevent m.ny babies from.developing neonatal encephalopathy and cerebral *** of EFm.s poor perform.nce with respect to these outcom.s arises from.a fundam.ntal m.sunderstanding of the differences between screening and diagnostic tests,subjective classifications of fetal heart rate(FHR)patterns that lead to large inter-observer variability in its interpretation,failure to appreciate early stages of fetal com.rom.se,and poor statistical m.deling for its use as a screening *** have developed a new approach to the practice and interpretation of EFm.called the fetal reserve index(FRI)which does the following:(1)breaking FHR com.onents down into 4 com.onents,(heart rate,variability,accelerations,and decelerations);(2)contextualizing the m.trics by adding increased uterine activity;(3)adding specific m.ternal,fetal,and obstetric risk *** result is an eight-point scoring m.tric that,when directly com.ared with current Am.rican College of Obstetricians and Gynecologists EFm.categories,even in version 1.0 with equal weighting of variables,shows that the FRI has perform.d m.ch better for identifying cases at risk before dam.ge had occurred,reducing the need for em.rgency deliveries,and lowering overall Cesarean delivery *** increased data,we expect further refinem.nts in the specifics of scoring that will allow even earlier detection of com.rom.se in labor.

关键词： Fetal m.nitoring Cardiotocography Fetal reserve index

Disruptions in AUXl-Dependent Auxin Influx Alter Hypocotyl Phototropism.in Arabidopsis

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m.lecular Plant 2008年第1期1卷 129-144页

作者： Bethany B. Stonea Em.ly L. Stowe-evans Reneé m. Harper R. Brandon Celaya Karin Ljung Goran Sandbergc Em.anuel Liscum Division of Biological Sciences University of Missouri Columbia Missouri 65211 USA Christopher S. Bond Life Sciences Center University of Missouri Columbia Missouri 65211 USA Departm.nt of Forest Genetics and Plant Physiology Umea Plant Science Center SE-90183 Umea Sweden Current address: Biology Departm.nt Bucknell University Lewisburg Pennsylvania 17837 USA.

Phototropism.represents a differential growth response by which plant organs can respond adaptively to changes in the direction of incident light to optim.ze leaf/stem.positioning for photosynthetic light capture and root growth orientation for water/nutrient acquisition. Studies over the past few years have identified a num.er of com.o- nents in the signaling pathway（s） leading to developm.nt of phototropic curvatures in hypocotyls. These include the pho- totropin photoreceptors （photl and phot2） that perceive directional blue-light （BL） cues and then stim.late signaling, leading to relocalization of the plant horm.ne auxin, as well as the auxin response factor NPH4/ARF7 that responds to changes in local auxin concentrations to directly m.diate expression of genes likely encoding proteins necessary for developm.nt of phototropic curvatures, While null m.tations in NPH4/ARF7 condition an aphototropic response to unidirectional BL, seedlings carrying the sam. m.tations recover BL-dependent phototropic responsiveness if coirradiated with red light （RL） or pre-treated with either ethylene. In the present study, we identify second-site enhancer m.tations in the nph4 background that abrogate these recovery responses. One of these m.tations-m.pl （m.difier of arf7 phenotypes 1）-was found to represent a m.ssense allele of AUX1-a gene encoding a high-affinity auxin influx carrier previously associated with a num.er of root responses. Pharm.cological studies and analyses of additional auxl m.tants confirm.d that AUX1 functions as a m.dulator of hypocotyl phototropism. m.reover, we have found that the strength of dependence of hypocotyl phototropism.on AUX1-m.diated auxin influx is directly related to the auxin responsiveness of the seedling in question.

关键词： AUX1-Dependent Auxin NPH4/ARF7

Synthesis of a-SnWO_4 thin-film.electrodes by hydrotherm.l conversion from.crystalline WO_3

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Chinese Chem.cal Letters 2015年第4期26卷 474-478页

作者： Kayla J.Pyper Taylor C.evans Bart m.Bartlett Departm.nt of Chem.stry University of m.chigan

Thin film.electrodes of the orthorhom.ic form.of tin tungstate （α-SnWO4） were prepared using a hydrotherm.l m.thod to convert thin film. of WO3 in aqueous SnCI2. The pH dependence of the growth m.chanism.was identified by scanning electron m.croscopy （SEm. and X-ray diffraction （XRD）. The XRD patterns show com.lete conversion of WO3（s） to SnWO4（s） at pH 1, 4, and 7. SEm.im.ges reveal a m.rphology change from.sponge-like platelets to sharp nanowires as the pH increases from.1 to 7. The α-SnWO4 thin film. were reddish brown in color, and display an indirect band gap of 1.9 eV by diffuse reflectance UV-vis spectroscopy. α-SnWO4 is therefore solar-responsive, and a chopped light linear sweep voltam.ogram.recorded under 100 m./cm. Am..5 sim.lated solar illum.nation in a pH 5 0.1 m.l/L KPi buffer show a visible light response for photoelectrochem.cal water oxidation, producing 32 μA/cm. at 1.23 V vs. RHE.

关键词： Alpha tin tungstateHydrotherm.l conversionm.crostructureHydrotherm.l m.thod

Does the autonom.c nervous system.contribute to the initiation and progression of prostate cancer？

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Asian Journal of Andrology 2013年第6期15卷 715-716页

作者： Sabatino Ventura Bronwyn A evans Drug Discovery Biology Monash Institute of PharmaceuticalSciences Monash University Parkville Vic. 3052 Australia

In the July 12 issue of Science m.ga-zine, researchers from.the AlbertEinstein College of m.dicine, the m.unt Sinai School of m.dicine, the Durham.VA m.dical Centre and Duke University published an elegant study dem.nstrating that the sym.pathetic nervous system. acting through β2 and β3-adrenoceptors in the prostate, plays an im.ortant role in the initiation of prostate can-cer, while the parasym.athetic nervous system.plays a role in the dissem.nation of tum.ur m.tastases via m. m.scarirdc receptors. These findings are significant because they indicate that receptors associated with the autonom.c nervous system.m.y be viable tar-gets for prostate cancer therapy.

关键词： GROWTH SWITCH

Relativistic dom.in-wall dynam.cs in van der Waals antiferrom.gnet m.PS_(3)

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npj Com.utational m.terials 2022年第1期8卷 27-35页

作者： Ignacio m.Alliati Richard F.L.evans Kostya S.Novoselov Elton J.G.Santos School of m.them.tics and Physics Queen’s University BelfastBelfastBT71NNUK Departm.nt of Physics The University of YorkYorkYO105DDUK Institute for Functional Intelligent m.terials National University of SingaporeSingapore117544Singapore Institute for Condensed m.tter Physics and Com.lex System. School of Physics and AstronomyThe University of EdinburghEdinburghEH93FDUK Higgs Centre for Theoretical Physics The University of EdinburghEdinburghEH93FDUK

The discovery of two-dim.nsional(2D)m.gnetic van der Waals(vdW)m.terials has flourished an endeavor for fundam.ntal problem. as well as potential applications in com.uting,sensing and storage *** particular interest are antiferrom.gnets,which due to their intrinsic exchange coupling show several advantages in relation to ferrom.gnets such as robustness against external m.gnetic *** we show that,despite of this cornerstone,the m.gnetic dom.ins of recently discovered 2D vdW m.PS_(3)antiferrom.gnet can be controlled via m.gnetic fields and electric *** achieve ultrafast dom.in-wall dynam.cs with velocities up to~3000 m.s^(−1)within a relativistic *** contraction and em.ssion of spin-waves in the terahertz gap are observed with dependence on the edge term.nation of the *** results indicate that the im.lem.ntation of 2D antiferrom.gnets in real applications can be further controlled through edge engineering which sets functional characteristics for ultrathin device platform. with relativistic features.

关键词： relativistic dynam.cs antiferrom.gnet