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A mathematical model of.circadian rhythms synchronization using f.actional dif.erential equations system of.coupled van der Pol oscillators

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International j.urnal of.Biomathematics 2018年第1期11卷 313-336页

作者： j. E. Escalante-Martf.ez j. f. gome.-aguilar C. Calderon-Ramon A. aguilar-Melendez P. Padilla-Longoria f.cultad de Ingenieria Mecdnica y Eldctrica Universidad Veracruzana Av. Venustiano Carranza S/N Col. Revolucidn C. P. 93390 Poza Riea Veracruz Mdxico CONACyT-TecnolSgico Nacional de Mexico/CENIDET Interior Internado Palmira S/N Col. Palmira C. P. 62490 Cuernavaca Morelos Mexico f.cultad de Ingenier~a Mecdnica y Eldctrica Universidad Veracruzana Av. Venustiano Carranza S/ZN Col. Revolucidn C. P. 93390 Poza Rica Veracruz Mexico f.cul$ad de Ingenierd Civil Universidad Veracruzana Av. Venustiano Carranza S/N Col. Revolucion C. P. 93390 Poza Rica Veracruz Mexico Instituto de Investigaciones en Matemdticas Aplicadas ySistemas (IIMAS) UNAM Circuito Escolar Cd. Universitaria Del. Coyoacan Mdxico D. F. C. P. 04510 Mexico

This paper presents an alternative representation of.a system of.dif.erential equations qualitatively showing the behavior of.the biological rhythm of.a crayf.sh during their transition f.om j.venile to adult stages. The model f.cuses on the interaction of.f.ur cellular oscillators coupled by dif.usion of.a hormone, a parameter μ is used to simu- late the quality of.communication among the oscillators, in biological terms, it mea- sures developmental maturity of.the crayf.sh. Since some quorum-sensing mechanism is assumed to be responsible f.r the synchronization of.the biological oscillators, it is nat- ural to investigate the possibility that the underlying dif.usion process is not standard, i.e. it may be a so-called anomalous dif.usion. In this case, it is well understood that dif.usion equations with f.actional derivatives describe these processes in a more realis- tic way. The alternative f.rmulation of.these equations contains f.actional operators of.Liouville-Caputo and Caputo-f.brizio type. The numerical simulations of.the equations ref.ect synchronization of.ultradian rhythms leading to a circadian rhythm. The classical behavior is recovered when the order of.the f.actional derivative is V = 1. We discuss possible biological implications.

关键词： Circadian rhythm van der Pol oscillators Liouville-Caputo f.actional oper-ator Caput^f.brizio f.actional operator Adams Bashf.rth Moulton method syn-chronicity.

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Synchronized bioluminescence behavior of.a set of.f.ref.ies involving f.actional operators of.Liouville-Caputo type

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International j.urnal of.Biomathematics 2018年第3期11卷 221-245页

作者： j. E. Escalante-Martínez j. f. Gómez-aguilar C. Calderón-Ramón A. aguilar-Meléndez P. Padilla-Longoria f.cultad de Ingenierla Mecdnica y Eldctrica Universidad Veracruzana Av. Venustiano Carranza S/N Col. Revolución C.P. 93390 Poza Rica Veracruz Mdéxico CONACyT- Tecnoldgico Nacional de México/CENIDET Interior Internado Palmira S/N Col. Palmira C.P. 62490 Cuernavaca Morelos México f.cultad de Ingeniería Mecdnica y Eléctrica Universidad Veracruzana Av. Venustiano Carranza S/N Col. Revolución C.P. 93390 Poza Rica Veracruz México f.cultad de Ingeniera Civil Universidad Veracruzana Av. Venustiano Carranza S/N Col. Revolución C.P. 93390 Poza Rica Veracruz México Instituto de Investigaciones en Matemdticas Aplicadas y Sistemas (IIMAS) UNAM Circuito Escolar Cd. Universitaria Del. Coyoacan México D.F. C.P. 04510 México

In this paper, a system of.f.actional dif.erential equations that model the synchronized bioluminescence behavior of.a set of.f.ref.ies put on two spatial arrangements is presented; the alternative representation of.these equations contains f.actional operators of.IAouvillc-Caputo type. The obj.ctive of.the model is to qualitatively recover synchronization and show that it is persistent. It is shown that the ef.ort made by each f.ref.y glow changes with respect to the number of.male competitors and the distance between them. The conditions on biological parameters are interpreted.

关键词： f.actional calculus Liouville Caputo f.actional derivative synchronicity f.ref.ies bioluminescence Adams Bashf.rth-Moulton method.

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Topsoil as Af.ected by Dung Deposition Under Resting Places of.Red Howler Monkey (Alouatta seniculus)

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Pedosphere 2008年第6期18卷 691-698页

作者： S. POUVELLE f. f.ER j. f. PONGE Musum National d'Histoire Naturelle CNRS UMR 7179 4 avenue du Petit-Chateau

The short-term inf.uence of.dung deposition and the f.rther redistribution of.dung by dung beetles were studied under a resting place of.the red howler monkey （Alouatta seniculus） living in tropical ralnf.rests of.South America. Monkey dung was experimentally clumped on the f.eld in a place used by troops of.howler monkeys f.r resting in the Nouragues Reserve Station, f.ench Guiana. Dung-treated plots were sampled serially over three weeks and compared with controls located in their immediate vicinity. The composition of.the soil matrix （top 10 cm） was studied in successive microlayers using an optical method. Under the inf.uence of.dung beetle activity, the topsoil became more homogeneous by losing its litter, its content in earthworm f.eces increased in the course of.time, and surf.ce mineral deposits were penetrated by roots. The results were interpreted in the light of.present knowledge on the ef.ects of.soil animal activity on plant growth and survival of.seedlings.

关键词： dung beetle activity earthworm f.eces roots tropical ralnf.rests

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Interf.cial ef.ects in electromagnetic coupling within piezoelectric phononic crystals

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Acta Mechanica Sinica 2009年第1期25卷 95-99页

作者： f. j. Sabina A.B.Movchan Instituto de Investigaciones en Matematicas Aplicadas yen Sistemas Universidad Nacional Autónoma de México Department of.Mathematical Sciences University of Liverpool

In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection between the electromechanical coupling and the ef.ects of.dispersion of.Bloch-f.oquet waves. A particular attention is given to structures containing interf.ces between dissimilar media and localization of.the electrical f.elds near such interf.ces.

关键词： Piezoelectric periodic composites Interf.ces Dispersion of.Bloch-f.oquet waves

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Oxidation and Coatings f.r Power Generation： New Super Ultra Critical Steam Turbines

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中国腐蚀与防护学报 2009年第4期29卷 318-319页

作者： f. j. PEREZ Grupo de Investigacion de Ingenieria de Superf.cies y Materiales Nanoestructurados U. C. M. N°910627 f.cultad de Ciencias Quimicas Universidad Complutense de Madrid. 28040 Madrid Spain

The steels with chromium contents between 9%and 12%wt are used f.r power plants with advanced steam oxidation *** present good creep properties as 9%Cr steels and good oxidation resistance,at the temperatures range between 500℃～600℃.In the last years numerous investigation in development of.coatings has been realized with the aim the protected them against the oxidation in order to allow operation of.steam turbines at 650℃.In this study,Al-Hf.protective coatings were deposited by CVD-f.R on f.rritic steel HCM-12A f.llowed by a dif.usion heat treatment,have shown to be protective at 650℃under steam f.r at least 3000 hours of.laboratory steam exposure under atmospheric *** and composition of.coatings were characterized by dif.erent techniques, such as scanning electron microscopy(SEM),electron probe microanalysis,and X-ray dif.raction(XRD). On the other hand,volatile species by mass spectrometry(MS) and thermogravimetric measurements (TG) during the initial stages oxidation of.the P92 f.rritic steel without and of.Al and Al/Si coating by chemical vapour deposition in f.uidized bed reactors(CVD-f.R) at 650℃in Ar+20%H_2O f.r 150 h were *** order to go f.rward to coatings design the Thermocalc code is used as base f.r the MSdata. TG-MS experiments were conducted in a closed steam loop in order to obtain inf.rmation about the oxyhydroxides f.rmation as reaction between coatings and *** those results the role of.the dif.erent coating element could be established and optimized f.r the coating *** oxidation mechanism based on the TG-MS results is *** morphology/composition and structure of.the oxidized samples were also studied using SEM/EDS and XRD techniques.

关键词：氧化金属腐蚀防护

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A comprehensive f.amework f.r exploratory spatial data analysis:Moran location and variance scatterplots

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International j.urnal of.Digital Earth 2010年第2期3卷 157-186页

作者： j.G.Negreiros M.T.Painho f.j.aguilar M.A.aguilar Institute of.Statistics and Inf.rmation Management New University of LisbonCampus de CampolideLisbon 1070-312Portugal Department of.Agricultural Engineering Almerı´a UniversityAlmeria 04120Spain

A signif.cant Geographic Inf.rmation Science(GIS)issue is closely related to spatial autocorrelation,a burning question in the phase of.inf.rmation extraction f.om the statistical analysis of.georef.renced *** present,spatial autocorrelation presents two types of.measures:continuous and *** it possible to use Moran’s I and the Moran scatterplot with continuous data?Is it possible to use the same methodology with discrete data?A particular and cumbersome problem is the choice of.the spatial-neighborhood matrix(W)f.r points *** paper addresses these issues by introducing the concept of.covariogram contiguity,where each weight is based on the variogram model f.r that particular dataset:(1)the variogram,whose range equals the distance with the highest Moran I value,def.nes the weights f.r points separated by less than the estimated range and(2)weights equal zero f.r points widely separated f.om the variogram range *** the W matrix is computed,the Moran location scatterplot is created in an iterative *** accordance with various lag distances,Moran’s I is presented as a good search f.ctor f.r the optimal neighborhood ***/transition regions are also *** the same time,a new Exploratory Spatial Data Analysis(ESDA)tool is developed,the Moran variance scatterplot,since the conventional Moran scatterplot is not sensitive to neighbor *** computer-mapping f.amework allows the study of.spatial patterns,outliers,changeover areas,and trends in an ESDA *** these tools were implemented in a f.ee web e-Learning program f.r quantitative geographers called SAKWeb#(or,in the near f.ture,***).

关键词： geocomputation exploratory spatial data analysis spatial autocorrelation Moran scatterplot Moran’s I variography

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The song remains the same： j.venile Richardson＇s ground squirrels do not respond dif.erentially to mother＇s or colony member＇s alarm calls

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Current Zoology 2012年第5期58卷 773-780页

作者： j.mes f. HARE Kurtis j. WARKENTIN Department of.Biological Sciences University of Manitoba Winnipeg MB Canada R3T 2N2 Department of.Zoology Brandon University Brandon MB R7A 6A9

Alarm calls are emitted by Richardson＇s ground squirrels Urocitellus richardsonii in response to avian and terrestrial predators. Conspecif.cs detecting these calls respond with increased vigilance, promoting predator detection and evasion, but in doing so, lose time f.om f.raging. That loss can be minimized if.alarm call recipients discriminate among signalers, and weight their response accordingly. f.r j.venile ground squirrels, we predicted that the trade-of. between f.raging and vigilance could be optimized via selective response to alarm calls emitted by their own dam, and/or neighboring colony members over calls broad- cast by less f.miliar conspecif.cs. Alarm calls of.adult f.male Richardson＇s ground squirrels were elicited in the f.eld using a predator model and recorded on digital audio tape. f.ee-living f.cal j.veniles were subj.cted to playbacks of.a call of.their mother, and on a separate occasion a call f.om either another adult f.male f.om their own colony, or an adult f.male f.om another colony. Neither immediate postural responses and escape behavior, nor the duration of.vigilance manif.sted by j.veniles dif.ered with exposure to alarm calls of.the three adult f.male signaler types. Thus, j.veniles did not respond pref.rentially to alarm calls emitted by their mothers or colony members, likely ref.ecting the high cost of.ignoring alarm signals where receivers have had limited opportunity to establish past signaler reliability [Current Zoology 58 （5）： 773-780, 2012].

关键词： Alarm Signal Communication Maternal Call Recognition Signal Reliability Ground Squirrel Social Discrimination

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Magnetic Behaviour of.Sm2Co7/f./Sm2 Co7, Nanocomposite Trilayers with Cr and Ti Additions

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Chinese Physics Letters 2009年第3期26卷 255-257页

作者： f. Shahzad S. A. Siddiqi j. Zhou Advaaced Light Source Berkeley Lab University of California Berkeley CA 94720 USA Centre f.r Solid State Physics University of the Punjab Lahore-54590 Pakistan Department of.Physics University of California Berkeley California 94720 USA

Trilayered Sm2Co7/f./Sm2Co7 spring exchange magnets are f.bricated by dc magnetron sputtering on MgO substrates. Very thin layers （0.3-0.7 nm） of.Cr and Ti are added at the interf.ces of.the two magnetic phases. The thickness of.StucCo7 is kept at 20nm and f. at 6nm while the thickness of.Cr and Ti are varied as 0.3, 0.5, and 0.7nm. The base pressure of.sputtering chamber is kept below 10^-7 Torr and Ar pressure at 3-8m Torr. The samples are characterized by x-ray dif.raction （XRD） and SQUID magnetometer. We report improvement in exchange coupling of.nonacomposite magnets by addition of.thin layers of.Cr at interf.ces.

关键词： No English Keywords

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f.brication and Characterization of.SmCo5/f.65Co35 and SmCo5/f. Composite Spring Exchange Magnets

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Chinese Physics Letters 2008年第7期25卷 2642-2644页

作者： f. Shahzad S. A. Siddiqi j. Zhou Centre f.r Solid State Physics University of the Punjab Lahore-54590 Pakistan Department of.Physics University of California Berkeley California-P4720 USA

SmCo5/f.65Co35 and SmCo5/f. spring exchange magnets are f.bricated by dc magnetron sputtering on MgO substrates and 100-nm-thick Si3N4 membranes, respectively. The base pressure of.sputtering chamber is kept below 10^-7 Tort, and Ar pressure is 3 to 8mTorr. The samples are characterized by an x-ray dif.ractometer, a superconducting quantum interf.rence magnetometer, and high resolution magnetic sof. x-ray microscopy. We obtain the complete exchange coupling and single phase behaviour of.composite magnets. The （BH）max value achieved is 28.8 MGOe.

关键词： the power-law exponents precipitation durative abrupt precipitation change

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Inf.uence of.Turbulators in Blade Cooling Passages on f.lm Hole Discharge Coef.icients

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j.urnal of.Thermal Science 2004年第3期13卷 245-254页

作者： H.-P. SCHIf.ER j. TAEGE f. HASELBACH Rolls-Royce Deutschland Eschenweg 11 D-15827 Dahlewitz GermanyRolls-Royce Deutschland Eschenweg 11 D-15827 Dahlewitz GermanyRolls-Royce Deutschland Eschenweg 11 D-15827 Dahlewitz Germany

This paper details the results of.a j.int proj.ct between Rolls-Royce Deutschland (RRD) and the Northwestern Polytechnical University of.China (NWPU). The obj.ctive of.the proj.ct was the determination of.the inf.uence of.tabulators in turbine blade cooling passages on f.lm hole discharge coef.icients (Cd coef.icients). A large-scale plexiglas model was used by the NWPU to measure the turbulator inf.uence on Cd coef.icients f.r a wide range of.dif.erent geometrical parameters, Reynolds numbers and cooling f.ow of. take ratios. RRD specif.ed the comprehensive test matrix and analysed the test data. The Cf. code f.UENT was used by RRD f.r numerical simulation of.the test cases with the main obj.ctive to support the interpretation of.observed trends. Both, experimental and numerical results will be presented in this paper f.r a selection of.test conf.gurations.

关键词： f.lm hole discharge coef.icient turbulator blade cooling.

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