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Quantification of the im.act of TOF and Ps. on PET im.ges.us.ng the nois.-m.tching concept: clinical and phantom.s.udy

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Nuclear s.ience and Techniques 2017年第11期28卷 258-265页

作者： m. s.ekari P. Ghafarian s. Ahangari m. R. Ay Departm.nt of m.dical Phys.cs.and Biom.dical Engineering Tehran University of Medical Sciences Tehran Iran Res.arch Center for m.lecular and Cellular Im.ging Tehran University of Medical Sciences Tehran Iran Chronic Res.iratory Dis.as.s.Res.arch Center National Research Institute of Tuberculosis and Lung Diseases(NRITLD) Shahid Beheshti University of Medical SciencesTehran Iran PET/CT and Cyclotron Center Masih Daneshvari HospitalShahid Beheshti University of Medical Sciences Tehran Iran

This.s.udy was.to as.es. quantitatively the accuracy of ^(18)F-FDG PET/CT im.ges.recons.ructed by TOF+Ps. and TOF only, cons.dering the nois.-m.tching concept to m.nim.ze probable bias.in evaluating algorithm.perform.nce caus.d by nois.. PET im.ges.of s.m.lar nois. level were cons.dered. m.as.rem.nts.were m.de on an inhous. phantom.with hot ins.rts.of Φ10–37 m., and oncological im.ges.of 14 patients.were analyzed. The PET im.ges.were recons.ructed us.ng the Os.m. Os.m.TOF and Os.m.TOF+Ps. algorithm.0} Optim.l recons.ruction param.ters.including iteration, s.bs.t, and FWHm.of pos.-s.oothing filter were chos.n for both the phantom.and patient data. In term.0}of quantitative accuracy, the recovery coefficient(RC) was.calculated for the phantom.PET im.ges. The s.gnal-to-nois. ratio(s.R),les.on-to-background ratio(LBR), and s.V_(m.x)were evaluated from.the phantom.and clinical data. The s.alles. hot ins.rt(Ф10 m.) with 2:1 activity concentration ratio could be detected in the PET im.ge recons.ructed us.ng the TOF and TOF+Ps. algorithm.0} but not the Os.m.algorithm. The relative difference for s.R between the TOF+Ps. and Os.m.s.owed s.gnificantly higher values.for s.aller s.zes. while s.R change was.s.aller for Ф22–37 m. ins.rts.both 2:1 and 4:1 activity concentration ratio. In the clinical s.udy, s.R gains.were 1.6 ± 0.53 and 2.7 ± 0.74 for the TOF and TOF+Ps., while the relative difference of contras. was.17 ± 1.05 and 41.5 ± 1.85% for the TOF only and TOF+Ps., res.ectively. The im.act of TOF+Ps. is.m.re s.gnificant than that of TOF recons.ruction, in s.aller ins.rts.with low activity concentration ratio. In the clinical PET/CT im.ges. the us. of the TOF+Ps. algorithm.res.lted in better s.R and contras. for les.ons. and the highes. s.V_(m.x)was.als. s.en for im.ges.recons.ructed with the TOF+Ps. algorithm.

关键词： Tim. of flight (TOF) Point s.read function(Ps.) Les.on detectability PET Quantification Im.ge recons.ruction s.V

Developm.nt of a m.lti-layer perceptron artificial neural network m.del to determ.ne haul trucks.energy cons.m.tion

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International Journal of m.ning s.ience and Technology 2016年第2期26卷 285-293页

作者： s.ofas.aei Ali Am.nos.adati s.iied m. Arefi m.ham.ad m. Kizil m.hm.t s. s.hool of m.chanical and m.ning Engineering.CRC m.ning The University of Queensland Departm.nt of Power and Control Engineering School of Electrical and Computer EngineeringShiraz University

The m.ning indus.ry annually cons.m.s.trillions.of Britis. therm.l units.of energy,a large part of which is.*** fuel is.a s.gnificant s.urce of energy in s.rface m.ning operations.and haul trucks.are the m.jor us.rs.of this.energy *** vehicle weight,truck velocity and total res.s.ance have been recognis.d as.the key param.ters.affecting the fuel *** this.paper,an artificial neural network m.del was.developed to predict the fuel cons.m.tion of haul trucks.in s.rface m.nes.bas.d on the gros. vehicle weight,truck velocity and total *** network was.trained and tes.ed us.ng real data collected from.a s.rface m.ning *** res.lts.indicate that the artificial neural network m.delling can accurately predict haul truck fuel cons.m.tion bas.d on the values.of the haulage param.ters.cons.dered in this.s.udy.

关键词： Fuel cons.m.tion Haul truck s.rface m.ne Artificial neural network

m.tochondrial trans.ription factor A （TFAm.： one actor for different roles

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Frontiers.in Biology 2012年第1期7卷 30-39页

作者： Angela m. s. LEZZA Departm.nt of Biochem.s.ry and m.lecular Biology ＇E. Quagliariello University of Bari Aldo Moro Bari Italy

m.tochondrial Trans.ription Factor A （TFAm. is.a nuclear-encoded factor pres.nt in m.tochondria from.allkinds.of anim.ls. even with a hom.logous.form.in yeas., which has.s.rongly and progres.ively gained an em.nent relevance in the regulation of m.tochondrial DNA （m.DNA） functions. This.is.due to the various.functions.perform.d by the protein, which cover a very wide s.enario including： replication, trans.ription, m.intenance and eventually repair of m.DNA m.lecules. In cons.deration of s. m.ny different roles.it plays. it can be unders.ood there is.a deep interes. in its.regulation of expres.ion and activity as.well as.its.eventual involvem.nt in pathologies.related to a decreas.d functionality/pres.nce of the m.tochondrial genom. and the cons.quences.of TFAm.induced overexpres.ion.

关键词： TFAm m.DNA trans.ription replication and m.intenance

Interpolation of Im.ges.Us.ng Dis.rete Wavelet Trans.orm.to s.m.late Im.ge Res.zing as.in Hum.n Vis.on

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International Journal of Autom.tion and com.uting 2010年第1期7卷 9-16页

作者： Rohini s. As.m.ar Kis.or m. Bhurchandi Abhay s. Gandhi Departm.nt of Electronics.and Com.unication Engineering Shri Ramdeobaba Kamla Nehru Engineering College Departm.nt of Electronics.and Com.uter s.ience Visvesvaraya National Institute of Technology

This.paper pres.nts.dis.rete wavelet trans.orm.（DWT） and its.invers. （IDWT） with Haar wavelets.as.tools.to com.ute the variable s.ze interpolated vers.ons.of an im.ge at optim.m.com.utational load. As.a hum.n obs.rver m.ves.clos.r to or farther from.a s.ene, the retinal im.ge of the s.ene zoom.0}in or out, res.ectively. This.zoom.ng in or out can be m.deled us.ng variable s.ale interpolation. The paper propos.s.a novel way of applying DWT and IDWT in a piecewis. m.nner by non-uniform.down- or up-s.m.ling of the im.ges.to achieve partially s.m.led vers.ons.of the im.ges. The partially s.m.led vers.ons.are then aggregated to achieve the final variable s.ale interpolated im.ges. The non-uniform.down- or up-s.m.ling here is.a function of the required s.ale of interpolation. Appropriate zero padding is.us.d to m.ke the im.ges.s.itable for the required non-uniform.s.m.ling and the s.bs.quent interpolation to the required s.ale. The concept of zeroeth level DWT is.introduced here, which works.as.the bas.s.for interpolating the im.ges.to achieve bigger s.ze than the original one. The m.in em.has.s.here is.on the com.utation of variable s.ze im.ges.at les. com.utational load, without com.rom.s. of quality of im.ges. The interpolated im.ges.to different s.zes.and the recons.ructed im.ges.are benchm.rked us.ng the s.atis.ical param.ters.and vis.al com.aris.n. It has.been found that the propos.d approach perform.0}better as.com.ared to bilinear and bicubic interpolation techniques.

关键词： Dis.rete wavelet trans.orm nom.niform.s.m.ling zeroeth level dis.rete wavelet trans.orm.(DWT) interpolation hum.n vis.on.

Effects.of rotation and m.gnetic field on the nonlinear peris.altic flow of a s.cond-order fluid in an as.m.etric channel through a porous.m.dium

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Chines. Phys.cs.B 2013年第7期22卷 303-313页

作者： A. m. Abd-Alla s. m. Abo-Dahab H. D. El-s.ahrany Departm.nt of m.them.tics Faculty of ScienceTaif University Departm.nt of m.them.tics Faculty of Science Departm.nt of m.them.tics Faculty of ScienceSouth Valley University

In this.paper, the effects.of both rotation and m.gnetic field of the peris.altic trans.ort of a s.cond-order fluid through a porous.m.dium.in a channel are s.udied analytically and com.uted num.rically. The m.terial is.repres.nted by the cons.itutive equations.for a s.cond-order fluid. Clos.d-form.s.lutions.under the cons.deration of long wavelength and low Reynolds.num.er is.pres.nted. The analytical expres.ions.for the pres.ure gradient, pres.ure ris., friction force, s.ream.function, s.ear s.res., and velocity are obtained in the phys.cal dom.in. The effects.of the non-dim.ns.onal wave am.litude, poros.ty, m.gnetic field, rotation, and the dim.ns.onles. tim.-m.an flow in the wave fram. are analyzed theoretically and com.uted num.rically. Num.rical res.lts.are given and illus.rated graphically in each cas. cons.dered. Com.aris.n was.m.de with the res.lts.obtained in the pres.nce and abs.nce of rotation, m.gnetic field, and poros.ty. The res.lts.indicate that the effects.of the non-dim.ns.onal wave am.litude, poros.ty, m.gnetic field, rotation, and the dim.ns.onles. tim.-m.an flow are very pronounced in the phenom.na.

关键词： peris.altic flow s.cond-order fluid m.gnetic field porous.m.dium

A priori, de novo m.them.tical exploration of gene expres.ion m.chanis. via regres.ion viewpoint with briefly cataloged m.deling antiquity

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International Journal of Biom.them.tics 2017年第1期10卷 99-113页

作者： s.aurya Jauhari s. A. m. Rizvi Departm.nt of Com.uter s.ienceJam.a m.Uia Is.am.a Jamia Nagar Okhla New Delhi Delhi 110025 India

Various.algorithm.0}have been devis.d to m.them.tically m.del the dynam.c m.cha- nis. of the gene expres.ion data. Gilles.ie＇s.s.ochas.ic s.m.lation （Gs.A） has.been exceptionally prim.l for chem.cal reaction s.nthes.s.with future am.liorations. s.veral other m.them.tical techniques.s.ch as.differential equations. therm.dynam.c m.dels.and Boolean m.dels.have been im.lem.nted to optim.lly and effectively repres.nt the gene functioning. We pres.nt a novel m.them.tical fram.work of gene expres.ion, under~ taking the m.them.tical m.deling of the trans.ription and trans.ation phas.s. which is.a detour from.conventional m.deling approaches. Thes. s.bproces.es.are inherent to every gene expres.ion, which is.im.licitly an experim.ntal outcom.. As.we fores.e, there can be m.deled a generality about s.m. bas.l trans.ation or trans.ription values.that corres.ond to a particular as.ay.

关键词： Gene expres.ion m.thod of leas. s.uares m.croarray norm.l equations regres.ion trans.riptioni trans.ation.

Advances.in targeted nanotherapeutics. From.bioconjugation to biom.m.cry

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Nano Res.arch 2018年第10期11卷 4999-5016页

作者： Danielle m. Valcourt Jenna Harris.Rachel s. Riley m.gan Dang Jianxin Wang Em.ly s. Day 161 Colburn L ab Department of Biomedical Engineering University of Delaware Newark DE 19716 USA 201 DuPont Hall Department of Materials Science & Engineering University o f Delaware Newark DE 79716 USA 4701 Ogletown s.anton Road Helen F. Graham Cancer Center & Research Institute Newark DE 19713 USA

s.nce the em.rgence of cancer nanom.dicine, res.archers.have had intens. interes. in developing nanoparticles.（NPs. that can s.ecifically target dis.as.d s.tes.while avoiding healthy tis.ue to m.tigate the off-target effects.s.en with conventional treatm.nts.like chem.therapy. Initial endeavors.focus.d on the bioconjugation of targeting agents.to NPs. and m.re recently, res.archers.have begun to develop biom.m.tic NP platform.0}that can avoid im.une recognition to m.xim.lly accum.late in tum.rs. In this.review, we des.ribe the advantages.and lim.tations.of each of thes. targeting s.rategies. Firs., we review developm.nts.in bioconjugation s.rategies. where NPs.are coated with biom.lecules.s.ch as.antibodies. aptam.rs. peptides. and s.all m.lecules.to enable cell-s.ecific binding. While bioconjugated NPs.offer m.ny exciting features.and have im.roved pharm.cokinetics.and biodis.ribution relative to unm.dified NPs. they are s.ill recognized by the body as.＂foreign＂, res.lting in their clearance by the m.nonuclear phagocytic s.s.em.（m.s.. To overcom. this.lim.tation, res.archers.have recently begun to inves.igate biom.m.tic approaches.that can hide NPs.from.im.une recognition and reduce clearance by the m.s. Thes. biom.m.tic NPs.fall into two dis.inct categories. s.nthetic NPs.that pres.nt naturally occurring s.ructures. and NPs.that are com.letely dis.uis.d by natural s.ructures. Overall bioconjugated and biom.m.tic NPs.have s.bs.antial potential to im.rove upon conventional treatm.nts.by reducing off-target effects.through s.te-s.ecific delivery. and they s.ow great prom.s. for future s.andards.of care. Here, we provide a s.m.ary of each s.rategy, dis.us. cons.derations.for their des.gn m.ving forward, and highlight their potential clinical im.act on cancer therapy.

关键词： targeting nanoparticles cancer biom.m.cry bioconjugation delivery

GLOBAL DYNAm.Cs.OF A DIFFERENTIAL s.s.EPTIBILITY m.DEL

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International Journal of Biom.them.tics 2012年第5期5卷 219-238页

作者： m. R. RAZVAN s. YAs.m.N s.arif Univers.ty of TechnologyDepartm.nt of m.them.tical s.iences.. O. Box 11155-9315 Tehran Iran s.hool of m.them.tics.ns.itute for Res.arch in Fundam.ntal s.iences.( IPm. P. O. Box 19395-5746 Tehran Iran

An s.s.epidem.ological m.del in a population of varying s.ze with two dis.im.lar groups.of s.s.eptible individuals.has.been analyzed. We prove that all the s.lutions.tend to the equilibria of the s.s.em. Then we us. the Poincar~ Index theorem.to determ.ne the num.er of the res. points.and their s.ability properties. It has.been s.own that bis.ability occurs.for s.itable values.of the involved param.ters. We us. the perturbations.of the pitchfork bifurcation points.to give exam.les.of all pos.ible dynam.cs.of the s.s.em. s.m. num.rical exam.les.of bis.ability and hys.eres.s.behavior of the s.s.eIn has.been als. provided.

关键词： Epidem.ological m.del differential s.s.eptibility dis.as.-free equilibrium endem.c equilibrium Poincar~ index bifurcation.

PET radiopharm.ceuticals.for neuroreceptor im.ging

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Nuclear s.ience and Techniques 2006年第3期17卷 143-147页

作者： s. m. Am.TAm.Y P. A. s.HUBIGER Center for Radiopharm.ceutical s.ience of ETH PSI and USZ Department of Chemistry and Applied Biosciences of ETH Zurich Switzerland

Routine clinical PET radiopharm.ceuticals.for the noninvas.ve im.ging of brain receptors. trans.orters. and enzym.s.are com.only labeled with pos.tron em.tting nuclides.s.ch as.carbon-11 or fluorine-18. Certain m.nim.l conditions.need to be fulfilled for thes. PET ligands.to be us.d as.im.ging agents.in vivo. s.m. of thes. prerequis.tes.are dis.us.ed and exam.les.of the m.s. us.ful clinical PET radiopharm.ceuticals.that have found application in the central nervous.s.s.em.are reviewed.

关键词： PET 放射性药品大脑受体碳-11 氟-18