Journal of Biological Physics最新文献_第9页

Heat transfer analysis for EMHD peristalsis of ionic-nanofluids via curved channel with Joule dissipation and Hall effects 考虑焦耳耗散和霍尔效应的弯曲通道离子纳米流体EMHD蠕动传热分析

IF 1.8 4区生物学

Journal of Biological Physics Pub Date : 2021-09-27 DOI: 10.1007/s10867-021-09582-9

Saba, Fahad Munir Abbasi, Sabir Ali Shehzad

{"title":"Heat transfer analysis for EMHD peristalsis of ionic-nanofluids via curved channel with Joule dissipation and Hall effects","authors":"Saba, Fahad Munir Abbasi, Sabir Ali Shehzad","doi":"10.1007/s10867-021-09582-9","DOIUrl":"10.1007/s10867-021-09582-9","url":null,"abstract":"<div><p>The objective of this research is to study the combined influences of applied electric and magnetic fields on the two-phase peristaltic motion of nanofluid through a curved channel. A two-phase model of a nanofluid, Maxwell’s model of thermal conductivity [1], and no-slip velocity and thermal boundary conditions have been used in this study. Hall effects, Joule heating (due to magnetic and electric fields), and viscous heating aspects are under consideration. Governing equations for the present flow configuration have been modeled and simplified by enforcing the lubrication scheme. Debye-Huckel approximation is used to obtain the analytical solution of the electric potential function (Poisson-Boltzmann equation). Resulting expressions are solved numerically through the NDSolve command in Mathematica and plotted in order to understand the effects of different dimensionless parameters on the temperature, stress, heat transmission rate, and fluid’s velocity. Graphical results demonstrated that the thermal transmission rate is augmented by increasing the Hartmann number, Brinkman number, and Debye-Huckel parameter while decreases for zeta potential ratio, Joule dissipation parameter, and electro-osmotic velocity. A decrease in axial velocity is noted near the lower wall for higher values of <span>({m}^{ast})</span>.</p></div>","PeriodicalId":612,"journal":{"name":"Journal of Biological Physics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2021-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10867-021-09582-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5066748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

Analysis of the effects of magnetic levitation to simulate microgravity environment on the Arp2/3 complex pathway in macrophage 磁悬浮模拟微重力环境对巨噬细胞Arp2/3复合物通路的影响分析

IF 1.8 4区生物学

Journal of Biological Physics Pub Date : 2021-09-17 DOI: 10.1007/s10867-021-09581-w

Sufang Wang, Nu Zhang, Jianglei Di, Wenjuan Zhao, Guolin Shi, Ruiheng Xie, Bohan Hu, Hui Yang

{"title":"Analysis of the effects of magnetic levitation to simulate microgravity environment on the Arp2/3 complex pathway in macrophage","authors":"Sufang Wang, Nu Zhang, Jianglei Di, Wenjuan Zhao, Guolin Shi, Ruiheng Xie, Bohan Hu, Hui Yang","doi":"10.1007/s10867-021-09581-w","DOIUrl":"10.1007/s10867-021-09581-w","url":null,"abstract":"<div><p>With dwindling natural resources on earth, current and future generations will need to explore space to new planets that will require travel under no or varying gravity conditions. Hence, long-term space missions and anticipated impacts on human biology such as changes in immune function are of growing research interest. Here, we reported new findings on mechanisms of immune response to microgravity with a focus on macrophage as a cellular model. We employed a superconducting magnet to generate a simulated microgravity environment and evaluated the effects of simulated microgravity on RAW 264.7 mouse macrophage cell line in three time frames: 8, 24, and 48 h. As study endpoints, we measured cell viability, phagocytosis, and used next-generation sequencing to explore its changing mechanism. Macrophage cell viability and phagocytosis both showed a marked decrease under microgravity. The differentially expressed genes (DEG) were identified in two ways: (1) gravity-dependent DEG, compared μg samples and 1 g samples at each time point; (2) time-dependent DEG, compared time-point samples within the same gravitational field. Through transcriptome analysis and confirmed by molecular biological verification, our findings firstly suggest that microgravity might affect macrophage phagocytosis by targeting Arp2/3 complex involved cytoskeleton synthesis and causing macrophage immune dysfunction. Our findings contribute to an emerging body of scholarship on biological effects of space travel.</p></div>","PeriodicalId":612,"journal":{"name":"Journal of Biological Physics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2021-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10867-021-09581-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4706108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

In silico simulation of the effect of hypoxia on MCF-7 cell cycle kinetics under fractionated radiotherapy 分次放疗下缺氧对MCF-7细胞周期动力学影响的硅模拟

IF 1.8 4区生物学

Journal of Biological Physics Pub Date : 2021-09-17 DOI: 10.1007/s10867-021-09580-x

Adrian S. Remigio

{"title":"In silico simulation of the effect of hypoxia on MCF-7 cell cycle kinetics under fractionated radiotherapy","authors":"Adrian S. Remigio","doi":"10.1007/s10867-021-09580-x","DOIUrl":"10.1007/s10867-021-09580-x","url":null,"abstract":"<div><p>The treatment outcome of a given fractionated radiotherapy scheme is affected by oxygen tension and cell cycle kinetics of the tumor population. Numerous experimental studies have supported the variability of radiosensitivity with cell cycle phase. Oxygen modulates the radiosensitivity through hypoxia-inducible factor (HIF) stabilization and oxygen fixation hypothesis (OFH) mechanism. In this study, an existing mathematical model describing cell cycle kinetics was modified to include the oxygen-dependent G1/S transition rate and radiation inactivation rate. The radiation inactivation rate used was derived from the linear-quadratic (LQ) model with dependence on oxygen enhancement ratio (OER), while the oxygen-dependent correction for the G1/S phase transition was obtained from numerically solving the ODE system of cyclin D-HIF dynamics at different oxygen tensions. The corresponding cell cycle phase fractions of aerated MCF-7 tumor population, and the resulting growth curve obtained from numerically solving the developed mathematical model were found to be comparable to experimental data. Two breast radiotherapy fractionation schemes were investigated using the mathematical model. Results show that hypoxia causes the tumor to be more predominated by the tumor subpopulation in the G1 phase and decrease the fractional contribution of the more radioresistant tumor cells in the S phase. However, the advantage provided by hypoxia in terms of cell cycle phase distribution is largely offset by the radioresistance developed through OFH. The delayed proliferation caused by severe hypoxia slightly improves the radiotherapy efficacy compared to that with mild hypoxia for a high overall treatment duration as demonstrated in the 40-Gy fractionation scheme.</p></div>","PeriodicalId":612,"journal":{"name":"Journal of Biological Physics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2021-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10867-021-09580-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4705151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Double-diffusion convective biomimetic flow of nanofluid in a complex divergent porous wavy medium under magnetic effects 磁作用下纳米流体在复杂多孔波介质中的双扩散仿生对流流动

IF 1.8 4区生物学

Journal of Biological Physics Pub Date : 2021-09-16 DOI: 10.1007/s10867-021-09583-8

Khurram Javid, Mohsan Hassan, Dharmendra Tripathi, Salahuddin Khan, Elena Bobescu, Muhammad Mubashir Bhatti

{"title":"Double-diffusion convective biomimetic flow of nanofluid in a complex divergent porous wavy medium under magnetic effects","authors":"Khurram Javid, Mohsan Hassan, Dharmendra Tripathi, Salahuddin Khan, Elena Bobescu, Muhammad Mubashir Bhatti","doi":"10.1007/s10867-021-09583-8","DOIUrl":"10.1007/s10867-021-09583-8","url":null,"abstract":"<div><p>We explore the physical influence of magnetic field on double-diffusive convection in complex biomimetic (peristaltic) propulsion of nanofluid through a two-dimensional divergent channel. Additionally, porosity effects along with rheological properties of the fluid are also retained in the analysis. The mathematical model is developed by equations of continuity, momentum, energy, and mass concentration. First, scaling analysis is introduced to simplify the rheological equations in the wave frame of reference and then get the final form of equations after applying the low Reynolds number and lubrication approach. The obtained equations are solved analytically by using integration method. Physical interpretation of velocity, pressure gradient, pumping phenomena, trapping phenomena, heat, and mass transfer mechanisms are discussed in detail under magnetic and porous environment. The magnitude of velocity profile is reduced by increasing Grashof parameter. The bolus circulations disappeared from trapping phenomena for larger strength of magnetic and porosity medium. The magnitude of temperature profile and mass concentration are increasing by enhancing the Brownian motion parameter. This study can be productive in manufacturing non-uniform and divergent shapes of micro-lab-chip devices for thermal engineering, industrial, and medical technologies.</p></div>","PeriodicalId":612,"journal":{"name":"Journal of Biological Physics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2021-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10867-021-09583-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4665323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Comparison of the histology and stiffness of ventricles in Anura of different habitats 不同生境无尾动物脑室组织学和硬度的比较

IF 1.8 4区生物学

Journal of Biological Physics Pub Date : 2021-09-13 DOI: 10.1007/s10867-021-09579-4

Megumi Ito, Yoshihiro Ujihara, Shukei Sugita, Masanori Nakamura

{"title":"Comparison of the histology and stiffness of ventricles in Anura of different habitats","authors":"Megumi Ito, Yoshihiro Ujihara, Shukei Sugita, Masanori Nakamura","doi":"10.1007/s10867-021-09579-4","DOIUrl":"10.1007/s10867-021-09579-4","url":null,"abstract":"<div><p>Vertebrate hearts have undergone marked morphological and structural changes to adapt to different environments and lifestyles as part of the evolutionary process. Amphibians were the first vertebrates to migrate to land. Transition from aquatic to terrestrial environments required the ability to circulate blood against the force of gravity. In this study, we investigated the passive mechanical properties and histology of the ventricles of three species of Anura (frogs and toads) from different habitats, <i>Xenopus laevis</i> (aquatic), <i>Pelophylax nigromaculatus</i> (semiaquatic), and <i>Bufo japonicus formosus</i> (terrestrial). Pressure-loading tests demonstrated stiffer ventricles of <i>P. nigromaculatus</i> and <i>B. j. formosus</i> compared <i>X. laevis</i> ventricles. Histological analysis revealed a remarkable difference in the structure of cardiac tissue: thickening of the compact myocardium layer of <i>P. nigromaculatus</i> and <i>B. j. formosus</i> and enrichment of the collagen fibers of <i>B. j. formosus.</i> The amount of collagen fibers differed among the species, as quantitatively confirmed by second-harmonic generation light microscopy. No significant difference was observed in cardiomyocytes isolated from each animal, and the sarcomere length was almost the same. The results indicate that the ventricles of Anura stiffen during adaptation to life on land.</p></div>","PeriodicalId":612,"journal":{"name":"Journal of Biological Physics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10867-021-09579-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4557291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Fitness landscapes for coupled map lattices 耦合地图格的适应度景观

IF 1.8 4区生物学

Journal of Biological Physics Pub Date : 2021-09-08 DOI: 10.1007/s10867-021-09577-6

Noelle Driver, Michael Frame

{"title":"Fitness landscapes for coupled map lattices","authors":"Noelle Driver, Michael Frame","doi":"10.1007/s10867-021-09577-6","DOIUrl":"10.1007/s10867-021-09577-6","url":null,"abstract":"<div><p>Our goal is to match some dynamical aspects of biological systems with that of networks of coupled logistic maps. With these networks we generate sequences of iterates, convert them to symbol sequences by coarse-graining, and count the number of times combinations of symbols occur. Comparison of this with the number of times these combinations occur in experimental data—a sequence of interbeat intervals for example—is a measure of the fitness of each network to describe the target data. The most fit networks provide a cartoon that suggests a decomposition of the experimental data into a component that may be produced by a simple dynamical subsystem, and a residual component, the result of detailed, particular characteristics of the system that generated the target data. In the space of all network parameters, each point corresponds to a particular network. We construct a fitness landscape when we assign a fitness to each point. Because the parameters are distributed continuously over their ranges, and because fitnesses are estimated numerically, any plot of the landscape involves a finite sample of parameter values. We’ll investigate how the local landscape geometry changes when the array of sample parameters is refined, and use the landscape geometry to explore complex relations between local fitness maxima.</p></div>","PeriodicalId":612,"journal":{"name":"Journal of Biological Physics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2021-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10867-021-09577-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4362643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spontaneous circulation of active microtubules confined by optical traps 受光阱限制的活性微管的自发循环

IF 1.8 4区生物学

Journal of Biological Physics Pub Date : 2021-09-08 DOI: 10.1007/s10867-021-09578-5

Stephen E Martin, Matthew E Brunner, Joshua M Deutsch

引用次数: 0

A continuum mechanics model for the Fåhræus-Lindqvist effect f<s:1> æus- lindqvist效应的连续介质力学模型

IF 1.8 4区生物学

Journal of Biological Physics Pub Date : 2021-07-03 DOI: 10.1007/s10867-021-09575-8

Angiolo Farina, Fabio Rosso, Antonio Fasano

{"title":"A continuum mechanics model for the Fåhræus-Lindqvist effect","authors":"Angiolo Farina, Fabio Rosso, Antonio Fasano","doi":"10.1007/s10867-021-09575-8","DOIUrl":"10.1007/s10867-021-09575-8","url":null,"abstract":"<div><p>The decrease in apparent relative viscosity that occurs when blood is made to flow through a tube whose diameter is less than about 0.3 mm is a well-known and documented phenomenon in physiology, known as the Fåhræus-Lindqvist effect. However, since the historical work of Fåhræus and Lindqvist (Amer. J. Physiol. <b>96</b>(3): pp. 562–568, 1931), the underlying physical mechanism has remained enigmatic. A widely accepted qualitative explanation was provided by Haynes (Amer. J. Physiol. <b>198</b>, pp. 1193–1200, 1960) according to which blood flows in microvessels with a core-annulus structure, where the erythrocytes concentrate within a central core surrounded by a plasma layer. Although sustained by observations, this conjecture lacks a rigorous deduction from the basic principles of continuum dynamics. Moreover, relations aimed to reproduce the blood apparent relative viscosity, extensively used in micro-circulation, are all empirical and not derived from the analysis of the fluid mechanical phenomena involved. In this paper, we apply the recent results illustrated in Guadagni and Farina (Int. J. Nonlinear Mech. <b>126</b>, p. 103587, 2020), with the purpose of showing that Haynes’ conjecture, slightly corrected to make it more realistic, can be proved and can be used to reach a sound explanation of the Fåhræus-Lindqvist effect based on continuum mechanics. We propose a theoretical model for the blood apparent relative viscosity which is validated by matching not only the original experimental data reported by Fåhræus and Lindqvist (Amer. J. Physiol. <b>96</b>(3), pp. 562–568, 1931), but also those provided by several subsequent authors.</p></div>","PeriodicalId":612,"journal":{"name":"Journal of Biological Physics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10867-021-09575-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4125165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Exciton transfer between LH1 antenna complex and photosynthetic reaction center dimer LH1天线复合物与光合反应中心二聚体之间的激子传递

IF 1.8 4区生物学

Journal of Biological Physics Pub Date : 2021-07-02 DOI: 10.1007/s10867-021-09576-7

Michal Pudlák, Richard Pinčák

引用次数: 1

Kinetic aspects of virus targeting by nanoparticles in vivo 纳米颗粒在体内靶向病毒的动力学方面

IF 1.8 4区生物学

Journal of Biological Physics Pub Date : 2021-06-02 DOI: 10.1007/s10867-021-09570-z

Vladimir P. Zhdanov

引用次数: 3