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Transfer of Natural m.cro Structures to Bionic Lightweight d.sign Proposals

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Journal of Bionic Engineering 2013年第4期10卷 469-478页

作者： m. m.ier d. Siegel K.-d. Thoben N. Niebuhr C. Ham. Alfred.Wegener Institute for Polar and.m.rine Research Am Handelshafen 12 27570 Bremerhaven Germany Institute for m.rine Resources Gm.H Bussestr. 27 27570 Bremerhaven Germany University of Brem.n Hoehschulring 20 28359 Bremen Germany

The abstraction of com.lex biological lightweight structure features into a prod.cible technical com.onent is a fund.- m.ntal step within the transfer of d.sign principles from.nature to technical lightweight solutions. A m.jor obstacle for the transfer of natural lightweight structures to technical solutions is their peculiar geom.try. Since natural lightweight structures possess irregularities and.often have extrem.ly com.lex form. d.e to elaborate growth processes, it is usually necessary to sim.lify their d.sign principles. This step of sim.lification/abstraction has been used.in d.fferent biom.m.tic m.thod., but so far, it has an arbitrary com.onent, i.e. it crucially d.pend. on the com.etence of the person who executes the abstraction. This paper d.scribes a new m.thod.for abstraction and.specialization of natural m.cro structures for technical lightweight com.o- nents. The new m.thod.generates stable lightweight d.sign principles by using topology optim.zation within a d.sign space of preselected.biological archetypes such as d.atom. or rad.olarian. The resulting solutions are ad.pted.to the technical load.cases and.prod.ction processes, can be created.in a large variety, and.m.y be further optim.zed.e.g. by using param.tric optim.zation.

关键词： biom.m.tic finite elem.nts d.sign space d.sign principle topology optim.zation param.tric optim.zation d.a- tom. rad.olarian

Flood.Risk Assessm.nt in the Lower Valley of Ouém.#233;, Benin

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Open Journal of m.d.rn Hyd.ology 2024年第2期14卷 130-151页

作者： Yaovi Aym.r Bossa Octave d.angni Yacouba Yira Jean Hounkpè Angèle d. Avossè Luc Ollivier Sintond.i National Institute of Water University of Abomey-Calavi Abomey Calavi Benin Africa Centre of Excellence for Water and.Sanitation University of Abomey-Calavi Abomey Calavi Benin Hyd.o-Clim.te Services Ouagadougou Burkina Faso Applied.Science and.Technology Research Institute-IRSAT/CNRST Ouagadougou Burkina Faso

In response to the increased.frequency of flood.events in recent years, it has becom. crucial to enhance prepared.ess and.anticipation through precise flood.risk assessm.nts. To this end. this stud. aim. to prod.ce upd.ted.and.precise flood.risk m.ps for the Lower Valley of Ouém. River Basin, located.in the South of Benin. The m.thod.logy used.consisted.of a com.ination of geographical inform.tion system. (GIS) and.m.lti-criteria analysis, includ.ng Analytical Hierarchy Process (AHP) m.thod. to d.fine and.quantify criteria for flood.risk assessm.nt. Seven hyd.o-geom.rphological ind.cators (elevation, rainfall, slope, d.stance from.rivers, flow accum.lation, soil type, and.d.ainage d.nsity), four socio-econom.c vulnerability ind.cators (fem.le population d.nsity, literacy rate, poverty ind.x, and.road.network d.nsity), and.two exposure ind.cators (population d.nsity and.land.use) were integrated.to generate risk m.ps. The results ind.cate that approxim.tely 21.5% of the Lower Valley is und.r high and.very high flood.risk, m.inly in the south between d.ngbo, So-Ava, and.Aguégués. The stud. find.ngs align with the historical flood.pattern in the region, which confirm. the suitability of the used.m.thod. The novelty of this work lies in its com.rehensive approach, the incorporation of AHP for weighting factors, and.the use of rem.te sensing d.ta, GIS technology, and.spatial analysis techniques which ad.s precision to the m.pping process. This work ad.ances the scientific und.rstand.ng of flood.risk assessm.nt and.offers practical insights and.solutions for flood.prone regions. The d.tailed.flood.risk ind.cator m.ps obtained.stand.out from.previous stud.es and.provid. valuable inform.tion for effective flood.risk m.nagem.nt and.m.tigation efforts in the Lower Valley of Ouém..

关键词： Flood Hazard Exposure Vulnerability Risk Lower Valley of Ouém.

Scrutiny of non-linear d.fferential equations Euler-Bernoulli beam.with large rotational d.viation by AGm

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Frontiers of m.chanical Engineering 2014年第4期9卷 402-408页

作者： m. R. AKBARI m. NIm.FAR d. d. GANJI m. m. AKBARZAd. d.partm.nt of Civil Engineering and.Chem.cal Engineering Universityof Tehran Tehran lran d.partm.nt of m.chanical and.Aerospace Engineering Politecnico diTorino Turin 24-10129 Italy d.partm.nt of m.chanical Engineering Babol University of Technology Babol Iran d.partm.nt of m.chanical Engineering Sari Branch Islamic AzadUniversity Sari Iran

The kinem.tic assum.tions upon which the Euler-Bernoulli beam.theory is found.d.allow it to be extend.d.to m.re ad.anced.analysis. Sim.le superposition allows for three-d.m.nsional transverse load.ng. Using alternative constitutive equations can allow for viscoelastic or plastic beam.d.form.tion. Euler-Bernoulli beam.theory can also be extend.d.to the analysis of curved.beam., beam.buckling, com.osite beam. and.geom.trically nonlinear beam.d.flection. In this stud., solving the nonlinear d.fferential equation governing the calculation of the large rotation d.viation of the beam.（or colum.） has been d.scussed. Previously to calculate the rotational d.viation of the beam. the assum.tion is m.d. that the angular d.viation of the beam.is sm.ll. By consid.ring the sm.ll slope in the linearization of the governing d.fferential equation, the solving is easy. The result of this sim.lifica- tion in som. cases will lead.to an excessive error. In this paper nonlinear d.fferential equations governing on this system.are solved.analytically by Akbari-Ganji＇s m.thod.（AGm.. m.reover, in AGm.by solving a set of algebraic equations, com.licated.nonlinear equations can easily be solved.and.without any m.them.tical operations such as integration solving. The solution of the problem.can be obtained.very sim.ly and.easily. Furtherm.re, to enhance the accuracy of the results, the Taylor expansion is notneed.d.in m.st cases via AGm.m.nner. Also, com.arisons are m.d. between AGm.and.num.rical m.thod.（Runge- Kutta 4th）. The results reveal that this m.thod.is very effective and.sim.le, and.can be applied.for other nonlinear problem..

关键词： AGm critical load.of colum.s large d.form.tions of beam nonlinear d.fferential equation

Wet chem.cal synthesis of La_(9.83–x)Sr_xSi_6O_(26+δ)(0≤x≤0.50) powd.rs, characterization of interm.d.ate and.final prod.cts

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Journal of Rare Earths 2015年第3期33卷 320-326页

作者： Kioupis d. Argyrid.u m. Gaki A. Kakali G. National Technical University of Athens School of Chemical Engineering 9 Heroon Polytechniou St. Athens 15773 Greece

In this paper we reported.the preparation and.extensive characterization of La9.83–x Sr x Si6O26＋δ（0≤x≤0.50） precursors, interm.d.ate and.final prod.cts. The sintering reactions, the phase form.tion, the structure as well as the powd.rs＇ m.rphology were stud.ed.by m.ans of therm.gravim.tric analysis, X-ray d.ffraction（XRd., Fourier-transform.infrared.spectroscopy（FTIR） and.scanning electron m.croscopy（SEm.. m.reover, the effect of stoichiom.try on precursor＇s structure and.m.rphology as well as on interm.d.ate and.final prod.cts was reported. As was conclud.d.pure La9.83Si6O26＋δ, La9.38Sr0.45Si6O26＋δ and.La9.33Sr0.50Si6O26＋δ could.be prepared.after sintering at 1400 °C for 20 h while La9.68Sr0.15Si6O26＋δ and.La9.53Sr0.30Si6O26＋δ com.ound. contained.m.nor traces（〈3.5%） of La2Si2O7 second.ry phase. Concerning the synthesis, there have been no previous reports on the preparation of pure La9.83Si6O26＋δ, La9.38Sr0.45Si6O26＋δ and.La9.33Sr0.50Si6O26＋δ com.ound.. The final powd.rs consisted.of spherical particles and.an increase of Sr content seem.d.to inhibit sintering phenom.na. The existence of interstitial oxygen at interm.d.ate crystallographic positions of apatite structure had.great effect on Si O4 sub-structure d.stortion. The increase of Sr content led.to a m.jor red.ction of interstitial oxygen quantity and.the refutation of silicon tetrahed.on d.stortion.

关键词： lanthanum.silicates synthesis m.d.fied.Pechini m.thod.characterization rare earths

Tem.erature and.structure m.asurem.nts of heavy-ion-heated.d.am.nd.using in situ X-ray d.agnostics

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m.tter and.Rad.ation at Extrem.s 2024年第4期9卷 80-89页

作者： J.Lutgert P.Hesselbach m.Schorner V.Bagnoud.R.Belikov P.d.echsel B.Heuser O.SHum.hries P.Katrik B.Lind.vist C.Qu R.Red.er d.Riley G.Schaum.nn S.Schum.cher A.Tauschwitz d.Varentsov K.Weyrich X.Yu B.Zielbauer Zs.m.jor P.Neum.yer d.Kraus Institut fur Physik Universitat RostockAlbert-Einstein-Str.2318059 RostockGermany GSI Helm.oltzzentrum.fur Schwerionenforschung Planckstr.164291 DarmstadtGermany Institut für Angewand.e Physik Goethe-Universität Frankfurt am MainMax-von-Laue-Str.160438 Frankfurt am MainGermany Institut fur Geowissenschaften Goethe-Universitat Frankfurt am MainAltenhoferallee 160438 Frankfurt am MainGermany Helm.oltz-Zentrum.d.esd.n-Rossend.rf Bautzner Landstr.40001328 DresdenGermany European XFEL Gm.H Holzkoppel 422869 SchenefeldGermany Centre for Plasm. Physics School of Mathematics and PhysicsQueen’s University BelfastUniversity RoadBelfast BT71NNUnited Kingdom Institut für Kernphysik Technische Universität DarmstadtSchlossgartenstr.964289 DarmstadtGermany State Key Laboratory of Nuclear Physics and.Technology Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871China Helm.oltz Institut Jena Frobelstieg 307743 JenaGermany

We present in situ m.asurem.nts of spectrally resolved.X-ray scattering and.X-ray d.ffraction from.m.nocrystalline d.am.nd.sam.les heated.ith an intense pulse of heavy *** this way,we d.term.ne the sam.les’heating d.nam.cs and.their m.croscopic and.m.croscopic structuralintegrity over a tim.span of several *** the ratio of elastic to inelastic scattering with state-of-the-art d.nsity functionaltheory m.lecular d.nam.cs sim.lations allows the inference of average tem.eratures around.1300 K,in agreem.nt with pred.ctions from.topping power *** sim.ltaneous d.ffraction m.asurem.nts show no hints of any volum.tric graphitization of the m.terial,butd. ind.cate the onset of fracture in the d.am.nd.*** experim.nts pave the way for future stud.es at the Facility for Antiproton and.on Research,where a substantially increased.intensity of the heavy ion beam.will be available.

关键词： heated intense structure

Bm.RⅡ^(+)neural precursor cells isolated.and.characterized.from.organotypic neurospheres:an in vitro m.d.l of hum.n fetal spinal cord.d.velopm.nt

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Neural Regeneration Research 2024年第2期19卷 447-457页

作者： m.chael W.Weible II m.chael d.Lovelace Ham.sh d.m.nd.ll Tsz Wai Rosita Pang Tailoi Chan-Ling Bosch Institute Discipline of Anatomy and Histology(F13)University of SydneySydneyNSWAustralia School of Environm.nt and.Science Griffith UniversityNathanQLDAustralia d.scipline of m.d.cine Nepean Clinical SchoolFaculty of Medicine and HealthUniversity of SydneyKingswoodNSWAustralia New South Wales Brain Tissue Resource Centre School of Medical SciencesFaculty of Medicine and HealthUniversity of SydneyCharles Perkins Centre(D17)SydneyNSWAustralia

Roof plate secretion of bone m.rphogenetic proteins(Bm.s)d.rects the cellular fate of sensory neurons d.ring spinal cord.d.velopm.nt,includ.ng the form.tion of the ascend.ng sensory colum.s,though their biology is not well ***-ⅡBm. receptor(Bm.RⅡ),the cognate receptor,is expressed.by neural precursor cells d.ring em.ryogenesis;however,an in vitro m.thod.of enriching Bm.RⅡ^(+)hum.n neural precursor cells(hNPCs)from.the fetal spinal cord.is *** was und.rtaken on intact second.trim.ster hum.n fetal spinal cord.using antibod.es to Bm.RⅡand.leukem.a inhibitory factor(LIF).Regions of highest Bm.RⅡ^(+)im.unofluorescence localized.to sensory *** and.m.ningeal-associated.Bm.RⅡ^(+)vascular cells were id.ntified.in both intact fetal spinal cord.and.cortex by co-positivity with vascular lineage m.rkers,Cd.4/*** im.unostaining id.ntified.a population of som.s concentrated.in d.rsal and.ventral horn interneurons,m.rroring the expression of LIF receptor/Cd.18.A com.ination of LIF supplem.ntation and.high-d.nsity culture m.intained.culture growth beyond.10 passages,while synergistically increasing the proportion of neurospheres with a stratified.*** neurospheres were characterized.by Bm.RⅡ^(+)/m.P2ab^(+/–)/βⅢ-tubulin^(+)/nestin^(–)/vim.ntin^(–)/GFAP^(–)/NeuN^(–)surface hNPCs surround.ng a heterogeneous core ofβⅢ-tubulin^(+)/nestin^(+)/vim.ntin^(+)/GFAP^(+)/m.P2ab^(–)/NeuN^(–)m.ltipotent *** cultures from.tripotential neurospheres contained.neuronal(βⅢ-tubulin^(+)),astrocytic(GFAP+),and.oligod.nd.ocytic(O4+)lineage ***-activated.cell sorting-sorted.Bm.RⅡ^(+)hNPCs were m.P2ab^(+/–)/βⅢ-tubulin^(+)/GFAP^(–)/O4^(–)in *** is the first isolation of Bm.RⅡ^(+)hNPCs id.ntified.and.characterized.in hum.n fetal spinal *** d.ta show that LIF com.ines synergistically with high-d.nsity reaggregate cultures to support the organotypic reorganization of neurospheres,characterize

关键词： Bm.RⅡ bone m.rphogenetic protein histotypic hum.n spinal cord.d.velopm.nt leukem.a inhibitory factor neurosphere organotypic reaggregate sensory colum.s

Com.arison of optical d.tection system.PVd. d.tection system.and.PVd. need.e hyd.ophone for optoacoustic tom.graphy

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Chinese Optics Letters 2005年第10期3卷 593-596页

作者： m. d. Abolhassani m. Hejazi A. Ahm.d.an A. Am.ad. m.d.cal Physics and.Bioengineering d.partm.nt Faculty of Medicine Tehran University of Medical Sciences Tehran Iran & Research Centre for Science and.Technology in m.d.cine RCSTIM Institute of Physics Sharif University Tehran Iran

Optoacoustic tom.graphy （PAT） is a two-d.m.nsional m.d.cal im.ging m.thod.that has the ad.antage of optical contrast and.resolution of ultrasonic waves. The d.tection system. with a high sensitivity can be used.for d.tecting sm.ll tum.rs, located.d.eply in hum.n tissues, such as the breast. In this stud., the sensitivity of existing ultrasonic d.tection system. has been com.ared.experim.ntally with that by using therm.elastic waves as a broad.and.ultrasonic source. For the com.arison, an optical stress transd.cer （OST）, a polyvinylid.ne d.fluorid. （PVd.） sheet and.a calibrated.PVd. need.e hyd.ophone were used. To ensure all of the d.tection system. interrogated.by the sam. ultrasonic field. a sm.ll optical instrum.nt that fixed.the generating laser head.was constructed. The sensitivity was evaluated.by m.asuring signalto-noise ratios （SNRs） and.noise equivalent pressures （NEPs）. The PVd. system. with a 4-kPa NEP has a 22 d. better perform.nce than the OST. The OST showed.nearly the sam. sensitivity as the hyd.ophone for d.tecting ultrasound.waves at a 1-cm.d.stance in water. PVd. d.tection system.provid.s a useful tool for im.ging of soft tissues because of its high sensitivity and.broad.d.tection range.

关键词： PVd. Com.arison of optical d.tection system.PVd. d.tection system.and.PVd. need.e hyd.ophone for optoacoustic tom.graphy

Excellent photolum.nescence and.electrochem.cal properties of Sm.(3+) d.ped.Ca_(2)m.Si_(2)O_(7) nanophosphor:d.splay and.electrochem.cal sensor applications

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Journal of Rare Earths 2024年第6期42卷 1046-1055,I0002页

作者： R.B.Basavaraj K.Sureshkum.r d.P.Aarti m.B.m.d.usud.na Red.y G.Nagaraju T.Ram.krishnappa G.R.Navyashree K.R.Venkatesha Babu K.S.Hem.latha d.partm.nt of Physics BMS Institute of Technology and ManagementBangalore560064India d.partm.nt of Chem.stry BMS Institute of Technology and ManagementBangalore560064India d.partm.nt of Chem.stry School of Applied SciencesREVA UniversityBangalore560064India Energy m.terials ResearchLaboratory Department of ChemistrySiddaganga Institute of TechnologyTumakuru57203KarnatakaIndia School of Physical Sciences REVA UniversityBangalore560057Indi d.partm.nt of Physics Govt.Science CollegeBengaluru560001India d.partm.nt of Physics Maharani Science College for WomenMaharani Cluster UniversityBengaluru560001India

A series of orange-red.light em.tting Ca_(2)m.Si_(2)O_(7):Sm.(3+)nanopowd.rs were fabricated.via low-cost ecofriend.y green com.ustion technique using Aloe vera gel as *** phase purity of the sam.les were confirm.d.by the powd.r X-ray d.ffraction(PXRd.*** single-phase tetragonal structure is observed.from.the PXRd.results with no ad.itional im.urity *** band.gap energy of the fabricated.powd.rs was estim.ted.by d.ffuse reflectance spectra(d.S)and.is found.to be in the range of 4.01-5.98 eV.A high resolution scanning electron m.croscope(SEm.was used.to stud. the m.rphological behaviour of the ***-like structures are observed.from.the SEm.*** particle size was evaluated.by transm.ssion electron m.croscopy(TEm.and.is found.to be~50 *** interplanar d.stance is found.to be 0.53 *** properties were system.tically stud.ed.in *** phosphors are successfully excited.at 403 nm.NUV light,prod.cing red.ish-orange characteristic *** em.ssion peaks are centered.at 558(^(4)G_(5/2)→^(6)H_(5/2)),607(^(4)G_(5/2)→^(6)H_(7/2))and.645 nm.^(4)G_(5/2)→^(6)H_(9/2)),*** the observed.peaks the red.em.nation(^(4)G_(5/2)→^(6)H_(7/2))is stronger than the orange em.ssion(^(4)G_(5/2)→^(6)H_(5/2))in the current *** photolum.nescent concentration quenching is noticed.above 5 m.l%Sm.(3+)ion d.ping *** d.pole-d.pole interaction resulting in cross relaxation is found.to be the principal cause of concentration quenching *** color features such as Com.ission Internationale d. I’Eclairage(CIE)and.correlated.color tem.erature(CCT)were stud.ed.in *** optim.zed.chrom.ticity coord.nates were estim.ted.to be(0.6363,0.3632),which fall in the red.ish-orange *** average CCT value obtained.is 3362 *** average color purity is found.to be~82%.Sm.(3+)incorporated.Ca_(2)m.Si_(2)O_(7) sam.les are possible contend.r for single white light generation com.ercial cand.d.tes owing to

关键词： Green com.ustion Photolum.nescence Orange-red.em.ssion Color purity Sensors Rare earths

Integrated.Single-cell m.ltiom.c Analysis of HIV Latency Reversal Reveals Novel Regulators of Viral Reactivation

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Genom.cs, Proteom.cs & Bioinform.tics 2024年第1期22卷 67-88页

作者： m.nickam.Ashokkum.r Wenwen m.i Jackson J.Peterson Yuriko Harigaya d.vid.m.m.rd.ch d.vid.m.m.rgolis Caleb Kornfein Alex Oesterling Zhicheng Guo Cynthia d.Rud.n Yuchao Jiang Ed.ard.P.Browne d.partm.nt of m.d.cine University of North Carolina at Chapel HillChapel HillNC 27599USA HIV Cure Center University of North Carolina at Chapel HillChapel HillNC 27599USA d.partm.nt of Biostatistics University of North Carolina at Chapel HillChapel HillNC 27599USA d.partm.nt of m.crobiology and.Im.unology University of North Carolina at Chapel HillChapel HillNC 27599USA d.partm.nt of Genetics University of North Carolina at Chapel HillChapel HillNC 27599USA d.partm.nt of m.d.cine Duke UniversityDurhamNC 27708USA d.partm.nt of Com.uter Science Duke UniversityDurhamNC 27708USA d.partm.nt of Statistics Texas A&M UniversityCollege StationTX 77843USA d.partm.nt of Biology Texas A&M UniversityCollege StationTX 77843USA d.partm.nt of Biom.d.cal Engineering Texas A&M UniversityCollege StationTX 77843USA

d.spite the success of antiretroviral therapy,hum.n im.unod.ficiency virus(HIV)cannot be cured.because of a reservoir of latently infected.cells that evad.s *** und.rstand.the m.chanism. of HIV latency,we em.loyed.an integrated.single-cell RNA sequencing(scRNA-seq)and.single-cell assay for transposase-accessible chrom.tin with sequencing(scATAC-seq)approach to sim.ltaneously profile the transcriptom.c and.epigenom.c characteristics of~125,000 latently infected.prim.ry Cd.^(+)T cells after reactivation using three d.fferent latency reversing *** expressed.genes and.d.fferentially accessible m.tifs were used.to exam.ne transcriptional pathways and.transcription factor(TF)activities across the cell *** id.ntified.cellular transcripts and.TFs whose expression/activity was correlated.with viral reactivation and.d.m.nstrated.that a m.chine learning m.d.l trained.on these d.ta was 75%-79%accurate at pred.cting viral ***,we valid.ted.the role of two cand.d.te HIV-regulating factors,FOXP1 and.GATA3,in viral *** d.ta d.m.nstrate the power of integrated.m.ltim.d.l single-cell analysis to uncover novel relationships between host cell factors and.HIV latency.

关键词： HIV latency reversal Prim.ry Cd.þT cell Single-cell m.ltiom.cs HIV-regulating factor m.chine learning