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The r.le of host r.fuge and str.ng Allee effects in a host-par.sitoid system

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Inter.ational j.ur.al of Biomathematics 2023年第5期16卷 111-135页

作者： Xiaochuan Hu sophia r.-j.jang Vinli Inc. DallasTX75206USA Depar.ment of Mathematics and Statistics Ter.s Tech Univer.ity LubbockTX 79409USA

We pr.pose and study a discr.te host-par.sitoid model of differ.nce equations with a spatial host r.fuge wher. hosts in the r.fuge patch ar. fr.e fr.m par.sitism but under.o a demogr.phic str.ng Allee *** the gr.wth r.te of hosts in the non-r.fuge patch is less than one,a host Allee thr.shold is der.ved below which both populations become *** is pr.ven that both populations can per.ist indefinitely if the host gr.wth r.te in the non-r.fuge patch exceeds one and the maximum r.pr.ductive number.of par.sitoids is gr.ater.than *** simulations r.veal that the host r.fuge can either.stabilize or.destabilize the host-par.sitoid inter.ctions,depending on other.model par.meter..A lar.e number.of par.sitoid tur.over.fr.m a par.sitized host may be detr.mental to the par.sitoids due to Allee effects in the hosts within the r.fuge ***,it is demonstr.ted numer.cally that if the host gr.wth r.te is not small,the population level of par.sitoids may suddenly dr.p to a small value as some par.meter. ar. var.ed.

关键词： Host r.fuge str.ng Allee effect stabilizing and destabilizing Bever.on-Holt gr.wth r.te Allee thr.shold maximum r.pr.ductive number

r.gulation of sleep by astr.cytes in the hypothalamic ventr.later.l pr.optic nucleus

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Neur.l r.gener.tion r.sear.h 2025年第4期20卷 1098-1100页

作者： j.e-Hong Kim r.qayya Afr.di Il-Sung jang Maan Gee Lee Kyoungho Suk Br.in Kor.a 21 four.KNU Conver.ence Educational Pr.gr.m of Biomedical Sciences for.Cr.ative Futur. Talents School of MedicineKyungpook National UniversityDaeguRepublic of Korea Depar.ment of Phar.acology School of MedicineKyungpook National UniversityDaeguRepublic of Korea Depar.ment of Phar.acology School of DentistryKyungpook National UniversityDaeguRepublic of Korea Br.in Science&Engineer.ng Institute Kyungpook National UniversityDaeguRepublic of Korea

Astr.cytes ar. functionally dynamic cells that suppor. neur.ns in multiple ways thr.ughout an or.anism’s *** astr.cytic r.gulation of neur.nal activity has been incr.asingly r.cognized in r.cent *** ar. now r.cognized as playing a mor. complex r.le than mer. bystander. in the centr.l ner.ous ***,their.r.le in r.gulating the sleep neur.cir.uitr. is not well *** this per.pective,we highlight the r.le of astr.cytes in sleep modulation,with a par.icular.focus on r.gulator. mechanisms r.lated to the ventr.later.l pr.optic nucleus(VLPO)of the *** br.efly discuss r.cent liter.tur. r.por.ing the r.le of VLPO astr.cytes in r.gulating sleep-associated behavior..

关键词： sleep ventr.later.l astr.cytes

Gene ther.py for.spinal muscular.atr.phy:per.pectives on the possibility of optimizing SMN1 deliver. to cor.ect all neur.logical and systemic per.ur.ations

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Neur.l r.gener.tion r.sear.h 2025年第7期20卷 2011-2012页

作者： Shar.n j.Br.wn r.fael j.Yáñez-Muñoz Heidi r.Fuller School of Phar.acy and Bioengineer.ng Keele UniversityKeeleUK Wolfson Center.for.Inher.ted Neur.muscular.Disease TORCH BuildingRJAH Orthopaedic HospitalOswestryUK *** Center of Gene and Cell TherapyDepartment of Biological SciencesSchool of Life Sciences and the EnvironmentRoyal Holloway University of LondonEghamUK

Spinal muscular.atr.phy(SMA)is a genetic condition that r.sults in selective lower.motor.neur.n loss with concomitant muscle weakness and *** genetic cause of SMA was under.tood in 1995 when loss or.impair.ent of the sur.ival motor.neur.n 1(SMN1)gene was identified as the main contr.buting factor.Lefebvr. et al.,1995).This,in combination with the discover. that humans have a“back-up”gene,SMN2,which can pr.duce low levels(appr.ximately 10%)of the full-length functional SMN pr.tein,has led to the gener.tion of SMA-specific gene *** was tr.ditionally classified accor.ing to age of symptom onset and developmental milestones achieved,with life expectancy and sever.ty var.ing between ***,SMN2 copy number.is used as a pr.xy for.the pr.diction of disease sever.ty,with higher.SMN2 copy number.typically being associated with r.duced sever.ty of SMA,although this r.lationship is not absolute:some individuals with low SMN2 copy number.have less sever. SMA phenotypes and vice ***,the etiology of SMA is fur.her.complicated by other.factor.,such as non-typical nucleotide var.ants and SMN2-independent modifier. of disease sever.ty.

关键词： atr.phy tr.ditionally absolute

Cooper.tive hunting in a discr.te pr.dator.pr.y system

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Inter.ational j.ur.al of Biomathematics 2020年第7期13卷 133-158页

作者： Yunshyong Chow sophia r.j.jang Hua-Ming Wang Institute of Mathematics Academia Sinica Taipei 10617Taiwan Depar.ment of Mathematics and Statistics Texas Tech Univer.ity LubbockTX 79409USA Depar.ment of Statistics Anhui Normal University Wuhu 241003AnhuiP.R.China

We pr.pose and investigate a discr.te-time pr.dator.pr.y system with cooper.tive hunting in the pr.dator.*** model is constr.cted fr.m the classical Nicholson-Bailey host-par.sitoid system with density dependent gr.wth r.te.A sufficient condition based on the model par.meter. for.which both populations can coexist is der.ved,namely that the pr.dator.s maximal r.pr.ductive number.exceeds *** study existence of inter.or.steady states and their.stability in cer.ain par.meter.*** is shown that the system behaves asymptotically similar.to the model with no cooper.tive hunting if the degr.e of cooper.tion is *** cooper.tive hunting,however.may pr.mote per.istence of the pr.dator.for.which the pr.dator.would other.ise go extinct if ther. wer. no cooper.tion.

关键词： Cooper.tive hunting discr.te pr.dator.pr.y system pr.dator.per.istence Neimar.-Sacker.bifur.ation

The effect of adsor.ent textur.l and functional pr.per.ies on model naphthenic acid adsor.tion

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j.ur.al of Envir.nmental Sciences 2025年第2期148卷 27-37页

作者： Tyler.M.r.y Elmir. Nazar. Oliver.K.L.Str.ng Paul r.Pede Andr.w j.Vr.ugdenhil Mater.al Science Department of ChemistryTrent University1600 West BankPeterboroughOntario K9L 0G2Canada Car.onix 690 Mountain RdSuite 200Fort William First NationOntario P7J 1G8Canada

Naphthenic acids,NAs,ar. a maj.r.contaminant of concer. and a focus of much r.sear.h ar.und r.mediation of oil sand pr.cess affected water.,*** activated car.on adsor.ents ar. an attr.ctive option given their.low cost of fabr.cation and implementation.A deeper.evaluation of the effect NA str.ctur.l differ.nces have on uptake affinity is *** we pr.vide an in-depth explor.tion of NA adsor.tion including many mor. model NA species than have been assessed pr.viously with evaluation of adsor.tion kinetics and isother.s at the r.levant alkaline pH of OSPW using sever.l differ.nt car.on adsor.ents with pH buffer.ng to simulate the behaviour.of r.al *** for.the NA var.ed consider.bly r.gar.less of the activated car.on used,r.nging fr.m 350 mg/g to near.zer. highlighting r.calcitr.nt *** equilibr.um data was explor.d to identify str.ctur.l featur.s of these species and key physiochemical pr.per.ies that influence *** found that cer.ainNAwill be r.sistant to adsor.tionwhen hydr.phobic adsor.ents ar. *** isother. modelling helped explor. inter.ctions occur.ing at the inter.ace between NA and adsor.ent *** identified the impor.ance of NA hydr.phobicity for.activated car.on *** is also pr.sented that indicates favor.ble hydr.gen bonding between cer.ain NA and sur.ace site hydr.xyl gr.ups,demonstr.ting the impor.ance of adsor.ent sur.ace functionality for.NA *** r.sear.h highlights the challenges associated with r.moving NAs fr.m OSPW thr.ugh adsor.tion and also identifies howadsor.ent sur.ace chemistr. modification can be used to incr.ase the r.moval efficiency of r.calcitr.nt NA species.

关键词： Adsor.tion Activated car.on Model naphthenic acids Isother. modelling

Fir.t Sear.h for.Pulsed CH Maser.Emission Stimulated by a Pulsar

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r.sear.h in Astr.nomy and Astr.physics 2025年第2期25卷 62-71页

作者： Mengting Liu Di Li j.r.Dawson j.el M.Weisber. Geor.e Hobbs Ningyu Tang Gan Luo Duo Xu Donghui Quan r.sear.h Center.for.Astr.nomical Computing Zhejiang Laboratory Depar.ment of Astr.nomy Tsinghua University National Astr.nomical Obser.ator.es Chinese Academy of Sciences CSIr. Astr.nomy & Space Science Australia Telescope National Facility School of Mathematical and Physical Sciences and Astr.physics and Space Technologies r.sear.h Centr. Macquarie University Depar.ment of Physics and Astr.nomy Carleton College Depar.ment of Physics Anhui Normal University Institut de r.dioastr.nomie Millimetr.que 300 Rue de la Piscine Canadian Institute for.Theor.tical Astr.physics University of Toronto 60 St.George Street

We pr.sent the fir.t sear.h for.pulsed CH maser.emission potentially stimulated by PSr.j.644-4559,conducted using the ultr.-wide-bandwidth low-fr.quency r.ceiver.on Mur.iyang,CSIr.'s Par.es r.dio *** tar.eted thr.e CHΛ-doublet tr.nsitions at 3264,3335,and 3349 MHz,with a var.ability timescale of78 *** detected ten CH emission featur.s at 3335 and 3349 MHz,and seven featur.s at 3264 MHz,dur.ng both pulsar.ON and pulsar.OFF *** obser.ed velocities align with the OH emission and absor.tion r.por.ed by a pr.vious study,suggesting a close spatial association between CH and OH *** der.ved column densities for.CH clouds within the Par.es beam r.nge fr.m 0.05 to 9.8×1013cm-2,indicating that these clouds ar. likely in diffuse and tr.nslucent *** limits for.CH column densities within the pulsar.beam r.nged fr.m 0.3 to 9.8×*** of these column densities suggests that CH clouds may exhibit clumpiness and *** significant stimulated emission featur. was detected in the optical depth ***,as par. of our.sear.h for.pulsed stimulated emission,we investigated the potential CH absor.tion of the pulsar.signal and found none,in agr.ement with astr.physical *** upper.limits for.the potential maser.amplification factor. towar.s PSr.j.644-4559 at 3264,3335,and 3349 MHz ar. 1.014,1.009,and 1.009,*** study demonstr.tes the feasibility of detecting pulsed CH maser.emission in the inter.tellar.medium stimulated by pulsar.photons.

关键词： (star.:) pulsar.: gener.l ISM: molecules maser.

Per.or.ance investigation of ar.ificial intelligence based contr.ller.for.thr.e phase four.leg shunt active filter

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Fr.ntier. in Ener.y 2015年第4期9卷 446-460页

作者： j. j.YACHANDr.N r. MUr.LI SACHITHANANDAM Depar.ment of Electr.cal and Electr.nics Engineer.ng SASTRA University Thanjavur 613401 India

In this paper. the choice of power.quality compensator.is a DSTATCOM which constitutes a thr.e phase four.leg voltage sour.e conver.er.（VSC） with a DC capacitor. The contr.l str.tegy pr.posed for.the DSTAT- COM is a neur.l networ. based one cycle contr.l （OCC）. This contr.l str.tegy involves neur.l networ. block, digital cir.uits and linear.elements, which eliminates the sensor. r.quir.d for.sensing the load cur.ent and coupling inductor.cur.ent in addition to the multiplier.employed in the conventional method. The calculation of har.onic and r.active cur.ents for.the r.fer.nce cur.ent gener.tion is also eliminated, thus minimizing the complexity in the contr.l str.tegy. The contr.l str.tegy mitigates har.onic/r.active cur.ents, ensur.s balanced and sinusoidal sour.e cur.ent fr.m the supply mains that ar. near.y in phase with the supply voltage, compensates neutr.l cur.ent, and maintains voltage acr.ss the capacitor.under.unbalanced sour.e and load conditions. The per.or.ance of the DSTATCOM with the pr.posed ar.ificial neur.l networ. （ANN） contr.ller. is validated and investigated thr.ugh simulations using Matlab softwar.. The simulation r.sults pr.ve the efficacy of the pr.posed neur.l networ. based contr.l str.tegy under.var.ing sour.e and load conditions.

关键词： neur.l networ. DSTATCOM neutr.l cur.entmitigation total har.onic distor.ion (THD) thr.e phasefour.wir. distr.bution system unbalanced and/or.distor.edsour.e

When and how did plate tectonics begin?Theor.tical and empir.cal consider.tions

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Chinese Science Bulletin 2007年第5期52卷 578-591页

作者： r. j. STEr. Geosciences Depar.ment University of Texas at Dallas Box 830688 Richardson TX 75083-0688 USA

板 tectonics 在对流传热的披风(岩流圈) 上是地球的热界面层(岩石圈) 的水平运动并且被岩石圈 inking 主要在 subduction 地区驾驶。板 tectonics 是组织的自我的一个突出的例子，远离平衡建筑群系统(SOFFECS ) ，由热界面层的否定快... 详细信息

板 tectonics 在对流传热的披风(岩流圈) 上是地球的热界面层(岩石圈) 的水平运动并且被岩石圈 inking 主要在 subduction 地区驾驶。板 tectonics 是组织的自我的一个突出的例子，远离平衡建筑群系统(SOFFECS ) ，由热界面层的否定快活开车并且由在弯曲岩石圈的驱散控制并且粘滞披风。板 tectonics 是一个不平常的方法让一个硅酸盐行星失去热，当它存在在上仅仅之一大在内部太阳系的五硅酸盐身体。构造活动和热损失的这个模式什么时候开始了，不被知道在地球上。所有硅酸盐行星可能经历了一个短命岩浆海洋阶段。在这团结的、停滞的盖行为是行星的热损失的普通模式以后，与内部，热被融化在更热的早地球中的火山作用和浅 *** 产生了的分层和“热点”正在失去一个不同岩石圈比今天，与更厚的海洋的外壳和更薄的披风岩石圈；如此的岩石圈将比花更长时间目前变得否定地快活，在早地球上建议那板 tectonics 偶发地发生了如果根本。板 tectonics 变得持续(现代风格) 当土足够地冷却了时，融化在散布山脉下面的那解压缩做了薄海洋的外壳，允许海洋的岩石圈在百万年中的一些十个以后变得否定地快活。板 tectonics 什么时候开始了的 Ultimatelythe 问题必须被从地质的记录检索的信息回答。标准因为板 tectonics 的操作包括 ophiolites，蓝片岩 andultr. 高的压力变形的带， eclogites，被动边缘，变换差错，不同 cr.tons 的不同运动的 paleomagneticdemonstr.tion，和在火的岩石中的诊断 geochemicaland 同位素示踪剂的存在。这个记录必须个别地被解释；我解释记录在锝? 从活跃太古代的 tectonics 和类似于板 tectonics 的 magmatismto 一些东西显示构造式样的前进 9 Ga 到有深 subduction 的持续、现代风格板 tectonics—并且强大的平板拉—在 Neopr.ter.zoic 时间开始。

关键词：板块构造形成时间形成机制俯冲前寒武纪地球动力学岩浆作用

Development of a r.r.faction wave at dischar.e initiation in a stor.ge silo--DEM simulations

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Par.icuology 2018年第1期16卷 37-49页

作者： r. Kobylka j. Hor.bik M. Molenda Institute of Agr.physics Polish Academy of Sciences ul. Doswiadczalna 4 20-290 Lublin Poland

The gener.tion of a r.r.faction wave at the initiation of dischar.e fr.m a stor.ge silo is a phenomenon of scientific and pr.ctical inter.st. The effect, sometimes ter.ed the dynamic pr.ssur. switch, may cr.ate danger.us pulsations of the stor.ge str.ctur.. Owing to the nonlinear.ty, discontinuity, and heter.geneity of gr.nular.systems, the mechanism of gener.tion and pr.pagation of str.ss waves is complex and not yet completely under.tood. The pr.sent study conducted discr.te element simulations to model the for.ation and pr.pagation of a r.r.faction wave in a gr.nular.mater.al contained in a silo. Modeling was per.or.ed for.a flat-bottom cylindr.cal container.with diameter.of 0.1 or.0.12 m and height of 0.5 m. The effects of the or.fice size and the shape of the initial dischar.ing impulse on the shape and extent of the r.r.faction wave wer. examined. Positions, velocities, and for.es of par.icles wer. r.cor.ed ever. 10-5 s and used to infer.the location of the fr.nt of the r.r.faction wave and loads on constr.ction member.. Dischar.e thr.ugh the entir. bottom of the bin gener.tes a plane r.r.faction wave that may be followed by a compaction wave, depending on the dischar.e r.te. Dischar.e thr.ugh the or.fice gener.tes a spher.cal r.r.faction wave that, after.r.flection fr.m the silo wall, tr.vels up the silo as a sequence of r.r.faction-compaction cycles with constant wavelength equal to the silo diameter. Dur.ng the tr.vel of the wave along the bin height, the wave amplitude incr.ases with the distance tr.veled. Simulations confir.ed ear.ier.findings of labor.tor. and numer.cal （finite element method） exper.ments and a theor.tical appr.ach, estimating the speed of the fr.nt of the r.r.faction wave to r.nge fr.m 70 to 80 m/s and the speed of the tail to r.nge fr.m 20 to 60 m/s.

关键词： Gr.nular.flow Dynamic pr.ssur. switch Discr.te element method Silo dischar.e Str.ss wave r.r.faction wave