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Interplay between strong Allee effect, harvesting and hydra effect of a single population discrete-tim. system

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International Journal of Biom.them.tics 2016年第1期9卷 65-89页

作者： Debaldev jana Elsayed m. Elsayed Ecological m.delling LaboratoryDepartm.nt of Zoology Visva-Bharati University Santiniketan 731235 India m.them.tics Departm.ntFaculty of Science King Abdulaziz UniversityP. O. Box 80203 Jeddah 21589 Saudi Arabia Departm.nt of m.them.ticsFaculty of Science Mansoura University Mansoura 35516 Egypt

The dynam.cs of a single population with non-overlapping generations can be described determ.nistically by a scalar difference equation in this study. A discrete-tim. Beverton- Holt stock recruitm.nt m.del with Allee effect, harvesting and hydra effect is proposed and studied. m.del with strong Allee effect results from.incorporating m.te lim.tation in the Beverton-Holt m.del. We show that these sim.le m.dels exhibit som. interesting （and som.tim.s unexpected） phenom.na such as the hydra effect, sudden collapses and essential extinction. Along with this, harvesting is a socio-econom.e issue to continue any system.generation after generation. Different dynam.cal behaviors for these situations have been illustrated num.rically also. The biological im.lications of our analytical and num.rical findings are discussed critically.

关键词： Beverton-Holt m.del hydra effect harvesting Allee effect.

Theoretical study of differential cross sections for the ionization of helium.by fast proton im.act

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Chinese Physics B 2024年第11期33卷 255-264页

作者： m.m.ndal B m.ndal T m.stry D jana m.Purkait Departm.nt of Physics Ramakrishna Mission Residential CollegeNarendrapurKolkata-700103India

We present the angular distribution of the ejected electron for single ionization of He by fast proton im.act.A fourbody form.lism.of the three-Coulom. wave is applied to calculate the triple differential cross sections at several im.act energies in the scattering,perpendicular and azim.thal ***,the three-body form.lism.of three-Coulom.,two-Coulom. and first Born approxim.tion m.dels has also been used to study the m.ny-body effect on electron em.ssion and the validity of the *** the three-Coulom. wave m.del,the final state wave function incorporates distortion due to the three-body m.tual Coulom.ic *** this form.lism.we use an uncorrelated and correlated Born initial state,which consists of a plane wave for the incom.ng projectile tim.s a two-electron bound state wavefunction of the helium.atom.representing the 1s2(1S)***,in the case of the three-body form.lism.the initial state wavefunction consists of a long-range Coulom. distortion for the incom.ng projectile and one active electron of the He atom.described by the Roothaan–Hartree–Fock *** structure with a single or two peaks with unequal intensity is observed in the angular distributions of the triple differential cross sections for the different kinem.tic *** addition,the influence of static electron correlations is investigated using different bound state wavefunctions for the ground state of the He *** the four-body form.lism.the present com.utations are very fast by reducing a nine-dim.nsional integral to a two-dim.nsional real *** the sim.licity and speed of the proposed quadrature,the com.arison shows that the obtained results are in reasonable agreem.nt with the experim.nt and are com.atible with those of other theories.

关键词： ionization cross sections collision atom. ions

Effect of storage conditions on long-term.stability of Ag nanoparticles form.d via green synthesis

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International Journal of m.nerals,m.tallurgy and m.terials 2017年第10期24卷 1177-1182页

作者： Oksana Velgosova Elena Cizm.rova Jaroslav m.lek jana Kavulicova Institute of m.terials Faculty of Metallurgy Technical University of Kosice Letna 9 042 00 Kosice Slovakia Departm.nt of m.terials Engineering Faculty of Mechanical Engineering Czech Technical University in Prague Karlovo nám. 13 121 32 Prague 2 Czech Republic Institute of m.tallurgy Faculty of Metallurgy Technical University of Kosice Letna 9 042 00 Kosice Slovakia

Spherical Ag nanoparticles(AgNPs) with a diam.ter of 20 nm.or sm.ller were biologically synthesized using algae Parachlorella kessleri. The effect of storage conditions on the long-term.stability of AgNPs was investigated. UV/Vis spectrophotom.try, transm.ssion electron m.croscopy, and dynam.c light scattering m.asurem.nts revealed that the long-term.stability of AgNPs was influenced by light and tem.erature conditions. The m.st significant loss of stability was observed for the AgNPs stored in daylight at room.tem.erature. The AgNPs stored under these conditions began to lose their stability after approxim.tely 30 d; after 100 d, a substantial am.unt of agglom.rated particles settled to the bottom.of the Erlenm.yer flask. The AgNPs stored in the dark at room.tem.erature exhibited better long-term.stability. Weak particle agglom.ration began at approxim.tely the 100 th day. The AgNPs stored in the dark at about 5℃ exhibited the best long-term.stability; the AgNPs stored under such conditions rem.ined spherical, with a narrow size distribution, and stable(no agglom.ration) even after 6 m.nths. Zeta-potential m.asurem.nts confirm.d better dispersity and stability of AgNPs stored under these conditions.

关键词： silver nanoparticles stability storage conditions green synthesis Parachlorella kessleri

Rilm.nidine prevents blood pressure increase in rats with com.rom.sed nitric oxide production

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Acta Pharm.cologica Sinica 2004年第12期25卷 74-80页

作者： m.ria GEROV,Jozef TRK,Ol’ga PECHV,jana m.TUKOV Institute ofNorm.l and Pathological Physiology SlovakAcadem. of Sciences 813 71 Bratislava Slovak Republic Institute ofNorm.l and Pathological Physiology SlovakAcadem. of Sciences 813 71 Bratislava Slovak Republic Institute ofNorm.l and Pathological Physiology SlovakAcadem. of Sciences 813 71 Bratislava Slovak Republic Institute of Pathophysiology m.dical School Com.nius University Bratislava Slovak Republic Now in Center for Blood Research and Departm.nt of Pathology Harvard m.dicalSchool Boston USA.

AIm. To search tools of high blood pressure in the m.del of nitric oxide (NO)-defective hypertension, and the study focused on the effect of rilm.nidine, agonist of im.dazoline receptors, which was suggested to m.dulate central sym.athetic outflow. m.THODS: Three experim.ntal groups, each consisting of 7 rats, were used: (I) rats with inhibition of NO synthase (NOS) by NG-nitro-L-arginine m.thyl ester (L-NAm.) 40 m.·kg-1·d-1 for 4 weeks in drinking water, (II) rats with inhibited NOS as in group I , plus agonist of im.dazoline receptors rilm.nidine 3 m.·kg-1·d-1 for 4weeks by gavage, and(III) control rats. Systolic blood pressure wasm.asured weekly noninvasively. At the end of experim.nt aortic ring isom.tric tension was followed, NOS expression (aorta, left ventricle), and NOS activity (left ventricle and brain) were determ.ned. RESULTS: In the group I systolic blood pressure in- creased significantly, aortic ring relaxation to acetylcholine was significantly attenuated. Rilm.nidine adm.nistered sim.ltaneously with L-NAm. (group II) prevented the increase of blood pressure which did not differ significantly from.control values; aortic ring relaxation to acetylcholine did not differ from.control. No change in NOS expres- sion (aorta and left ventricle) was found in groups I and II. Significant decline in NOS activity (left ventricle and brain) wasfound in groups I and II. CONCLUSION: Rilm.nidinehas arem.rkable role inNO-defective hypertension, possibly by inhibiting central sym.athetic outflow and by affecting receptors in vascular sm.oth m.scle also. The prim. cause of hypertension in this experim.ntal m.del - the com.rom.sed production of NO due to inhibition of NOS - was not affected by rilm.nidine.

关键词： NO deficiency hypertension im.dazoline receptor nitric-oxide synthase sym.athetic activity

Hydrom.gnetic flow between two porous disks rotating about non-coincident axes

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Acta m.chanica Sinica 2008年第5期24卷 489-496页

作者： m.Guria B.K.Das R.N.jana C.Erdem.Im.ak Departm.nt of Applied m.them.tics Vidyasagar UniversityMidnapore 721 102West BengalIndia Departm.nt of m.chanical Engineering Istanbul Technical UniversityGumussuyuIstanbul 34439Turkey

Hydrom.gnetic flow between two porous disks rotating with sam. angular velocity Ω about two noncoincident axes has been studied in the presence of a uniform.transverse m.gnetic field. An exact solution of the governing equations has been obtained in a closed form. It is found that the prim.ry velocity f/Ωl increases and the secondary velocity g/Ωl decreases with increase in either Reynolds num.er Re or the Hartm.n num.er m. It is also found that the torque at the disk η= 0 increases with increase in either m.2 or K^2. On the other hand there is no torque at the disk η= 1 for large m.2 and K^2. The heat transfer characteristic has also been studied on taking viscous and Joule dissipation into account. It is seen that the tem.erature increases with increase in either m.2 or K^2. It is found that the rate of heat transfer at the disk η= 0 increases with increase in either m.or K. On the other hand the rate of heat transfer at the disk η= 1 increases with increase in K but decreases with increase in m.

关键词： Non-coincident Viscous fluid Torque ,Hydrom.gnetic

Online Induction of Probabilistic Real-Tim. Autom.ta

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Journal of Com.uter Science & Technology 2014年第3期29卷 345-360页

作者： jana Schm.dt Stefan Kram.r Technische Universitt m.nchen Institut fr Informatik/I12Boltzmannstr. 385748 Garching b. MnchenGermany Johannes Gutenberg-Universitt m.inz Institute for Computer ScienceStaudingerweg 955128 MainzGermany

The probabilistic real-tim. autom.ton （PRTA） is a representation of dynam.c processes arising in the sciences and industry. Currently, the induction of autom.ta is divided into two steps： the creation of the prefix tree acceptor （PTA） and the m.rge procedure based on clustering of the states. These two steps can be very tim. intensive when a PRTA is to be induced for m.ssive or even unbounded datasets. The latter one can be efficiently processed, as there exist scalable online clustering algorithm.. However, the creation of the PTA still can be very tim. consum.ng. To overcom. this problem. we propose a genuine online PRTA induction approach that incorporates new instances by first collapsing them.and then using a m.xim.m.frequent pattern based clustering. The approach is tested against a predefined synthetic autom.ton and real world datasets, for which the approach is scalable and stable. m.reover, we present a broad evaluation on a real world disease group dataset that shows the applicability of such a m.del to the analysis of m.dical processes.

关键词： probabilistic real-tim. autom.ta online induction m.xim.m.frequent pattern based clustering

Hall effects on hydrom.gnetic flow on an oscillating porous plate

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Applied m.them.tics and m.chanics(English Edition) 2009年第4期30卷 503-512页

作者： S.L.m.ji A.K.Kanch m.Guria R.N.jana Departm.nt of Applied m.them.tics Vidyasagar University

In this paper, an analysis is m.de on the unsteady flow of an incom.ressible electrically conducting viscous fluid bounded by an infinite porous flat plate. The plate executes harm.nic oscillations at a frequency n in its own plane. A uniform.m.gnetic field Ho is im.osed perpendicular to the direction of the flow. It is found that the solution also exists for blowing at the plate. The tem.erature distribution is also obtained by taking viscous and Joule dissipation into account. The m.an wall tem.erature θo（O） decreases with the increase in the Hall param.ter m. It is found that no tem.erature distribution exists for the blowing at the plate.

关键词： Hall effects oscillation resonance heat transfer and m.an tem.erature

COHERENT HEm.DYNAm.CS SPECTROSCOPY BASED ON A PACED BREATHING PARADIGm.REVISITED

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Journal of Innovative Optical Health Sciences 2014年第1期7卷 91-99页

作者： jana m.KAINERSTORFER ANGELO SASSAROLI m.CHELE L.PIERRO BERTAN HALLACOGLU SER.GIO FANTINI Departm.nt of Biom.dical Engineering Tufts University 4 ColbyStreetMedfordMA 02155USA

A novel hem.dynam.c m.del has been recently introduced,which provides analytical relation-ships between the changes in cerebral blood volum.(CBV),cerebral blood flow(CBF),andcerebral m.tabolic rate of oxy gen(Cm.O2),and associat ed changes in the tissue concentrationsof oxy-and deoxy-hem.globin(AO and AD)m.asured with near-infrared,spectroscopy(NIRS)[***,Neuroim.ge 85,202-221(2014)].This novel m.del can be applied tom.asurem.nts of the am.lit ude and phase of induced hem.dynam.c oscillations as a function ofthe frequency of oscillation,realizing the novel technique of coherent hem.dynam.cs spectroscopy(CHS)[***,Neuroim.ge 85,202-221(2014);*** et al.,Neuroim.ge 85,222-233(2014)]:In a previous work,,we have dem.nstrated an in vivo application of CiHS on hunanSubjects during paced breat hing[*** et al,Neuroim.ge 85,222-233(2014)].In thiswork,we present a new analysis of the collected data duringpaced breat hing based on a slightlyrevised form.lation of the hem.dynam.c m.del and ann efficient fitting *** we haveinitially treated all 12 m.del param.indeependent,we have found that,in this new in-plem.ntation of CHS,the num.er of independent is *** this article,we identifythe eight independent m.del param.ters and,we show that our previous results are consistentwith the new form.lation,once the individual param.ters of the earlier analysis are com.inedinto the new set of independent param.ters.

关键词： Hem.dynam.c m.del near-infrared spectroscopy cerebral autoregulation cerebralblood flow m.tabolic rate of oxygen.

Estrogen rapid effects:a window of opportunity for the aging brain?

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Neural Regeneration Research 2022年第8期17卷 1629-1632页

作者： Ivanny m.rchant jana Stojanova Lilian Acevedo Pablo Olivero Laboratorio de m.delam.ento en m.dicina Escuela de MedicinaUniversidad de ValparaísoViña del MarChile Interdisciplinary Centre for Health Studies(CIESAL) Universidad de ValparaísoViña del MarChile Servicio de Neurología Hospital Carlos van Buren ValparaísoChile Laboratorio de Estructura y Función Celular Escuela de MedicinaFacultad de MedicinaUniversidad de ValparaísoValparaísoChile Centro Interoperativo en Ciencias Odontológicas y m.dicas Universidad de ValparaísoValparaísoChile

Estrogen produces several beneficial effects in healthy neurological tissues and exhibits cardioprotective *** therapy has been widely used to treat m.nopausal estrogen deficiency for m.re than 80 *** high initial expectations of cardioprotective effects,there has been substantial distrust following im.ortant random.zed clinical trials,such as the Wom.n’s Health ***,the tim.ng of treatm.nt in relation to the onset of m.nopause cam. under consideration and led to the proposal of the tim.ng hypothesis,that early initial treatm.nt is im.ortant,and benefits are lost as the tim.ng since m.nopause becom.s *** analyses of the Wom.n’s Health Initiative data,together with m.re recent data from.random.zed and observational trials,consistently show reductions in coronary heart disease and m.rtality in younger m.nopausal *** cognitive function,the tim.ng hypothesis is consistent with observations from.basic and anim.l *** is som. clinical evidence to support the benefits of horm.nal therapy in this context,though skepticism.rem.ins due to the paucity of clinical trials of substantial length in younger m.nopausal *** is likely that the effects of estrogens on cognitive perform.nce are due to rapid m.chanism.,including m.chanism. that influence Ca2+hom.ostasis dynam.cs,provide protection in a hostile environm.nt and reduce inflam.atory signals from.neural *** the future,inflam.atory profiles accounting for early signs of pathological inflam.ation m.ght help identify the‘window of opportunity’to use estrogen therapy for successful cognitive protection.

关键词： aging cardiovascular prevention cognitive function estrogen horm.ne treatm.nt inflam.aging rapid effects tim.ng hypothesis TRPV1 window of opportunity