Academic literature on the topic 'Active Granular Matter'
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Journal articles on the topic "Active Granular Matter"
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Morse, Peter K., Sudeshna Roy, Elisabeth Agoritsas, Ethan Stanifer, Eric I. Corwin, and M. Lisa Manning. "A direct link between active matter and sheared granular systems." Proceedings of the National Academy of Sciences 118, no. 18 (April 30, 2021): e2019909118. http://dx.doi.org/10.1073/pnas.2019909118.
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The similarity in mechanical properties of dense active matter and sheared amorphous solids has been noted in recent years without a rigorous examination of the underlying mechanism. We develop a mean-field model that predicts that their critical behavior—as measured by their avalanche statistics—should be equivalent in infinite dimensions up to a rescaling factor that depends on the correlation length of the applied field. We test these predictions in two dimensions using a numerical protocol, termed “athermal quasistatic random displacement,” and find that these mean-field predictions are surprisingly accurate in low dimensions. We identify a general class of perturbations that smoothly interpolates between the uncorrelated localized forces that occur in the high-persistence limit of dense active matter and system-spanning correlated displacements that occur under applied shear. These results suggest a universal framework for predicting flow, deformation, and failure in active and sheared disordered materials.
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Li, Shengkai, Bahnisikha Dutta, Sarah Cannon, Joshua J. Daymude, Ram Avinery, Enes Aydin, Andréa W. Richa, Daniel I. Goldman, and Dana Randall. "Programming active cohesive granular matter with mechanically induced phase changes." Science Advances 7, no. 17 (April 2021): eabe8494. http://dx.doi.org/10.1126/sciadv.abe8494.
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At the macroscale, controlling robotic swarms typically uses substantial memory, processing power, and coordination unavailable at the microscale, e.g., for colloidal robots, which could be useful for fighting disease, fabricating intelligent textiles, and designing nanocomputers. To develop principles that can leverage physical interactions and thus be used across scales, we take a two-pronged approach: a theoretical abstraction of self-organizing particle systems and an experimental robot system of active cohesive granular matter that intentionally lacks digital electronic computation and communication, using minimal (or no) sensing and control. As predicted by theory, as interparticle attraction increases, the collective transitions from dispersed to a compact phase. When aggregated, the collective can transport non-robot “impurities,” thus performing an emergent task driven by the physics underlying the transition. These results reveal a fruitful interplay between algorithm design and active matter robophysics that can result in principles for programming collectives without the need for complex algorithms or capabilities.
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Cheng, Ke, Peng Liu, Mingcheng Yang, and Meiying Hou. "Experimental investigation of active noise on a rotor in an active granular bath." Soft Matter 18, no. 13 (2022): 2541–48. http://dx.doi.org/10.1039/d1sm01798e.
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The spectrum of the noise experienced by a passive rotor immersed in an active granular bath is experimentally investigated, which gives a direct evidence supporting an exponentially-correlated active noise.
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Miao, Guoqing, Kai Huang, Yi Yun, and Rongjue Wei. "Active thermal convection in vibrofluidized granular systems." European Physical Journal B 40, no. 3 (September 2004): 301–4. http://dx.doi.org/10.1140/epjb/e2004-00277-7.
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Lim, Melody X., Anton Souslov, Vincenzo Vitelli, and Heinrich M. Jaeger. "Cluster formation by acoustic forces and active fluctuations in levitated granular matter." Nature Physics 15, no. 5 (March 4, 2019): 460–64. http://dx.doi.org/10.1038/s41567-019-0440-9.
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Sánchez, R., and P. Díaz-Leyva. "Self-assembly and speed distributions of active granular particles." Physica A: Statistical Mechanics and its Applications 499 (June 2018): 11–19. http://dx.doi.org/10.1016/j.physa.2018.01.031.
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Bär, Markus, Robert Großmann, Sebastian Heidenreich, and Fernando Peruani. "Self-Propelled Rods: Insights and Perspectives for Active Matter." Annual Review of Condensed Matter Physics 11, no. 1 (March 10, 2020): 441–66. http://dx.doi.org/10.1146/annurev-conmatphys-031119-050611.
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A wide range of experimental systems including gliding, swarming and swimming bacteria, in vitro motility assays, and shaken granular media are commonly described as self-propelled rods. Large ensembles of those entities display a large variety of self-organized, collective phenomena, including the formation of moving polar clusters, polar and nematic dynamic bands, mobility-induced phase separation, topological defects, and mesoscale turbulence, among others. Here, we give a brief survey of experimental observations and review the theoretical description of self-propelled rods. Our focus is on the emergent pattern formation of ensembles of dry self-propelled rods governed by short-ranged, contact mediated interactions and their wet counterparts that are also subject to long-ranged hydrodynamic flows. Altogether, self-propelled rods provide an overarching theme covering many aspects of active matter containing well-explored limiting cases. Their collective behavior not only bridges the well-studied regimes of polar self-propelled particles and active nematics, and includes active phase separation, but also reveals a rich variety of new patterns.
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Teplitskii, Yu A., V. L. Malevich, and D. G. Belonovich. "Characteristics of active thermal insulation based on infiltrated granular bed." Journal of Engineering Physics and Thermophysics 86, no. 2 (March 2013): 292–99. http://dx.doi.org/10.1007/s10891-013-0833-z.
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Ramaswamy, Sriram, and R. Aditi Simha. "The mechanics of active matter: Broken-symmetry hydrodynamics of motile particles and granular layers." Solid State Communications 139, no. 11-12 (September 2006): 617–22. http://dx.doi.org/10.1016/j.ssc.2006.05.042.
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Jason Gao, Guo-Jie, Michael C. Holcomb, Jeffrey H. Thomas, and Jerzy Blawzdziewicz. "Embryo as an active granular fluid: stress-coordinated cellular constriction chains." Journal of Physics: Condensed Matter 28, no. 41 (August 22, 2016): 414021. http://dx.doi.org/10.1088/0953-8984/28/41/414021.
Full textDissertations / Theses on the topic "Active Granular Matter"
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Briand, Guillaume. "Etude expérimentale des phases denses d'un liquide de disques durs actifs." Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLET040/document.
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Au cours de cette thèse nous avons étudié expérimentalement les phases denses de disques polaires vibrés, un bon modèle de liquide actif.L'expérience consiste à mettre en vibration des disques durs designés avec deux pattes avant et arrière différentes. Cela leur confère une polarité et sous l'effet de la vibration les disques avancent avec persistance dans la direction de leur polarité.Il a été montré que ce disque polaire est un bon modèle de particule active. Par ailleurs, il a été observé que ces disques forment un liquide polaire ordonnée pour des fractions surfaciques autour de 0.40.Au cours de cette thèse nous avons travaillé à plus haute densité pour étudier la cristallisation de ce liquide actif. Nous avons observé une dynamique fortement intermittente au cours de laquelle des agrégats denses et ordonnés se forment mais se fragmentent sans cesse. Ce régime perdure jusqu'à la fraction surfacique de 0.83, la plus élevée que nous ayons pu atteindre dans un premier temps.Pour étudier l'existence éventuelle d'une phase cristalline stable, nous avons réalisé des expériences dans une enceinte hexagonale, où il est possible d'imposer des fractions surfaciques de l'ordre de 0.89 proche de celle de l'empilement hexagonal compact. Nous observons un cristal dans le cas où l'enceinte est totalement remplie, en revanche lorsque que l'on retire quelques disques le cristal se met à tourner de manière spectaculaire tout en conservant un ordre positionnel.Enfin, nous avons réalisé des expériences de mesures de pression mécanique. Nous avons observé que la pression mécanique exercée par les disques polaires dépend de la nature des murs de l'enceinte. On conclu que la pression mécanique n'est pas une variable d'état pour ce systèmeDuring this thesis, we studied experimentally the dense phases of vibrated polar disks, a good model of active liquid.The experiment involves vibrating hard discs with two different front and rear legs. This provides them with a polarity such that they perform persistent directed motion when they are shaken vertically.These polar discs has been shown to be a good active particle model. Moreover, it has been observed that these disks form an ordered polar liquid for surface fractions around 0.40.During this thesis we worked at a higher density to study the crystallization of this active liquid. We observed a highly intermittent dynamics during which dense and ordered aggregates form but are constantly fragmented. This regime lasts until the surface fraction of 0.83, the highest that we have been able to reach at first.In order to study the possible existence of a stable crystal phase, we carried out experiments in a hexagonal arena, where it is possible to impose surface fractions of the order of 0.89 close to that of the compact hexagonal packing. We observe a crystal in the case where the arena is completely filled, however when removing a few discs the crystal flows and rotates spectacularly while maintaining a positional order.Finally, we carried out mechanical pressure measurement experiments. We have observed that the mechanical pressure exerted by the polar disks depends on the nature of the walls of the arena. We conclude that mechanical pressure is not a state variable for this system
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Lidon, Pierre. "Effet d'ultrasons de puissance sur les matériaux mous : vers des matériaux "acousto-rhéologiques"." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEN014/document.
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Les méthodes d'imagerie et de vélocimétrie ultrasonores ont prouvé leur efficacité pour étudier des matériaux divers. À haute intensité, il est connu que les ultrasons exercent des forces stationnaires dans les fluides newtoniens, par le biais d'effets non linéaires comme la pression de radiation acoustique. Néanmoins, ces effets n'ont encore jamais été exploités d'un point de vue fondamental dans le contexte de la physique des matériaux mous. L'objet de cette thèse est d'exploiter l'interaction d'ultrasons de puissance avec des matériaux bloqués afin de sonder activement, voire d'influencer leurs propriétés mécaniques. Nous proposons tout d'abord une méthode de microrhéologie active : la « mésorhéologie acoustique ». En analysant le mouvement d'un intrus sous l'effet de la pression de radiation acoustique, nous caractérisons localement la rhéologie du matériau étudié. Nous mettons cette technique en œuvre avec un fluide à seuil simple : un microgel de carbopol. Nous exploitons les résultats obtenus à la lumière d'une caractérisation rhéologique poussée du comportement de ce matériau en dessous de son seuil d'écoulement et proposons diverses pistes d'amélioration du dispositif.Ensuite, nous décrivons la mise en écoulement d'un empilement granulaire immergé par des ultrasons intenses focalisés et comparons les observations aux résultats de simulations de dynamique moléculaire. La transition de fluidification observée car l'injection d'énergie y est discontinue. Elle est intermittente et hystérétique, propriétés reproduites par des simulations numériques et dont un modèle phénoménologique simple permet de rendre compte.Enfin, en remplaçant le plan d'un rhéomètre classique par un transducteur ultrasonore, nous mesurons l'effet de vibrations à haute fréquence sur les propriétés mécaniques d'un gel colloïdal fragile de noir de carbone. Nous observons un effet significatif et potentiellement irréversible des ultrasons sur le module élastique et sur la mise en écoulement de ce système. Les vibrations semblent favoriser le glissement du gel aux parois mais il semble toutefois qu'elles induisent également des changements en volume dans l'échantillonUltrasonic imaging and velocimetry has been proved to be very efficient methods to study various materials. At high intensity, ultrasonic waves are known to exert steady forces in newtonian fluid through nonlinear effects like the acoustic radiation pressure. However those effects have never been used in fundamental studies of the physics of soft materials. This thesis aims at exploiting the interaction between high intensity ultrasound and soft jammed materials to probe actively and even modify their mechanical properties.We first introduce an alternative technique for active microrheology we called « acoustic mesorheology ». By analyzing the motion of an intruder under the acoustic radiation pressure we characterize locally the rheology of the system under study. We test this technique on a simple yield stress fluid, namely a carbopol microgel. We compare the results with those obtained by standard rheology measurements of the behaviour of this gel under its yield stress.Then we describe the fluidization of an immersed granular packing by high intensity focused ultrasound. We compare our observations with the results of molecular dynamics simulations. The obtained fluidization is original as the injection of energy is discontinuous in time. It is hysteretic and intermittent and those properties are well captures by both simulations and a phenomenological model.Finally, we replace the plane of a standard cone-plate rheometer by an ultrasonic transducer. This allows us to characterize the effect of high frequency vibrations on the rheology of a fragile carbon black gel. We observe a significant and eventually irreversible effect of ultrasound on the elastic modulus and on the yielding of the system. Vibrations are shown to favor wall slip but seem to induce changes in the volume of the sample though
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Olson, Christopher C. "Designing Active Granular Squares." 2016. https://scholarworks.umass.edu/masters_theses_2/369.
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The goal of this thesis has been to find a means of i) designing an active square particle, and ii) continuously varying its degree of activity with the objective of understanding the effects of activity on the various phases of granular matter. The motivations, results and limitations of our methods of creating active particles are discussed in this thesis. The applicability of a stochastic model based on the Langevin equation in 2D as well as implications for future experiments are also discussed.
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Soni, Harsh. "Flocks, Flow and Fluctuations in Inanimate Matter : Simulations and Theory." Thesis, 2015. https://etd.iisc.ac.in/handle/2005/4229.
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In this thesis we study a novel soft-matter system that imitates motility. Our system consists of a few asymmetrically tapered brass rods and aluminium beads which are confined between two vertically shaking plates. The rods are motile due to interplay of their the fore-aft asymmetric shape, vibrational energy input, and the mechanics of contact with the bounding surfaces. Experiments done by our col-
laborators revealed that the system undergoes a phase transition from a disordered state to an ordered coherently moving flock above a critical bead concentration. We have used time-driven numerical simulations and analytical theory to understand
the physics underlying the phenomenon.
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MANACORDA, ALESSANDRO. "Lattice models for granular and active matter fluctuating hydrodynamics." Doctoral thesis, 2017. http://hdl.handle.net/11573/1135222.
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This thesis investigates the common nature of granular and active systems, which is rooted in their intrinsic out-of-equilibrium behavior, with the aim of finding minimal models able to reproduce and predict the complex collective behavior observed in experiments and simulations. Granular and active matter are among the most studied systems in out-of-equilibrium statistical physics.
The thesis guides readers through the derivation of a fluctuating hydrodynamic description of granular and active matter by means of controlled and transparent mathematical assumptions made on a lattice model. It also shows how a macroscopic description can be provided from microscopic requirements, leading to the prediction of collective states such as cooling, swarming, clustering and the transitions among them. The analytical and numerical results shed new light on the physical connection between the local, microscopic properties of few particles and the macroscopic collective motion of the whole system.
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Bera, Pradip Kumar. "Non-Equilibrium Phenomena in Sheared Soft Matter and Active Granular System." Thesis, 2019. https://etd.iisc.ac.in/handle/2005/4474.
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In this thesis, we have studied non-equilibrium phenomena in sheared soft matter systems and in granular active matter. The surfactant systems are driven out of thermal equilibrium by applying external forcing at the boundary. We have used rheology, in-situ x-ray scattering techniques, in-situ optical microscopy to study the flow behavior and the structural changes of surfactant gels and Langmuir monolayers. The flow of soft gel and colloidal glass below their yield stress shows large burst in the shear rate due to internal reorganization as confirmed by in-situ optical microscopy. The statistical properties of the shar rate fluctuations resembles those observed in ground acceleration in earth-quakes, like Omori law, Gutenberg-Richter law and power law distribution of inter-occurrence time. The ordered mesh phase under shear shows isomorphic twinning transition having slightly different lattice parameters, giving rise to the splitting of the Bragg peaks and the six or eight points modulation of the Bragg rings. The rheology of the surfactant’s Langmuir monolayer shows a phase transition at yield strain separating the absorbing to fluctuating steady state. Further, the Grazing Incidence X-ray Diffraction of peptide-lipid monolayer at the air-water interface has been studied to understand the effect of shear on the structural properties of 2D nano-crystallites. In the second part, we have studied the effect of dissenters on the collective behavior of particles which have a tendency to flock. The system of two-step-tapered rods undergoes the flocking phase transition at a threshold area fraction φc ∼ 0.12 having high orientational correlations between the particles. However, the one-step-tapered rods (same as the two-step-tapered rods but without the 1mm middle step) do not flock. We use these one-step-tapered rods as the motile dissenters in the flock-forming granular matter of aligners (the two-step-tapered rods). We mix and disperse them to follow the system in the steady-state and our experiments give a quantitative estimation of dissenter’s effects on the flocking. At the critical fraction of dissenters, f ∼ 0.3, the flocking order of the system gets destroyed completely. The variance of the system’s order parameter shows a maximum near the dissenter fraction f ∼ 0.05, suggesting a finite-size crossover between the ordered and disordered phases.JRF and SRF fellowships from University Grants Commission (UGC)
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FAZZINO, Filippo. "A novel integrated treatment for mature landfill leachate via active filtration and anaerobic digestion." Doctoral thesis, 2022. http://hdl.handle.net/11570/3225916.
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The final disposal of end-of-life products in landfills has caused waste accumulation over the years with consequent soil, water and air pollution. Particularly, landfill leachate poses a serious threat to fresh and ground water, air and soil quality. Leachate is the result of the water percolating through landfilled waste which concentrates biological and chemical constituents of waste. Leachate must be collected during landfill operations (and even after landfill closure) and treated before its discharge in the environment. Dissolved organic matter, toxic and persistent organic compounds, ammonium, heavy metals and metalloids, chlorine compounds, dioxins and emerging contaminants are the main pollutants present in leachate. Moreover, leachate coming from mature landfills (i.e., > 10 years old) has slightly alkaline pH and is rich in hardly biodegradable or non-biodegradable organic matter (e.g., humic substances). These peculiarities make mature landfill leachate (MLL) treatment challenging. This thesis investigated an innovative MLL treatment at a laboratory-scale on the basis of Circular Economy principles. A synthetic MLL was pre-treated using active granular filters (Zero Valent Iron, ZVI, mixed with Lapillus and Granular Activated Carbon, GAC, respectively) with the aim of reducing heavy metals and other contaminants refractory to biological treatment. Both filters showed positive results in terms of metals removal. Afterwards, the pre-treated aqueous matrix was used as a nutrient solution useful for the metabolism of bacteria involved in the anaerobic digestion of a biodegradable organic substrate. As a result of the process, produced methane can be used for energy generation and residual digestate can replace fertilisers due to the presence of nitrogen and HSs deriving from the pre-treated MLL. Whilst the digestion of pure cellulose (model organic substrate) was adversely affected by pre-treated MLL addition, conversely, the use of a more realistic substrate (i.e., market waste) seemed to trigger the beneficial effects of pre-treated MLL on the process which resulted stable and efficient. Accordingly, it can be stated that the feasibility of this MLL treatment has been proved at a laboratory-scale. Further research consisting of larger scales experiments and life cycle analyses needs to be carried out in order to optimise operational parameters of both processes prior to a possible full-scale application.
Books on the topic "Active Granular Matter"
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Manacorda, Alessandro. Lattice Models for Fluctuating Hydrodynamics in Granular and Active Matter. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-95080-8.
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Manacorda, Alessandro. Lattice Models for Fluctuating Hydrodynamics in Granular and Active Matter. Springer, 2018.
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Manacorda, Alessandro. Lattice Models for Fluctuating Hydrodynamics in Granular and Active Matter. Springer International Publishing AG, 2019.
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(Editor), Victor Starov, and Ivan Ivanov (Editor), eds. Fluid Mechanics of Surfactant and Polymer Solutions (CISM International Centre for Mechanical Sciences). Springer, 2004.
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Starov, Victor, and Ivan Ivanov. Fluid Mechanics of Surfactant and Polymer Solutions. Springer London, Limited, 2014.
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Terentjev, Eugene M., and David A. Weitz, eds. The Oxford Handbook of Soft Condensed Matter. Oxford University Press, 2015. http://dx.doi.org/10.1093/oxfordhb/9780199667925.001.0001.
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This Handbook serves both as an introduction and an overview of the field of soft condensed matter. The discussion covers topics ranging from the fundamentals of colloid science to the principles and action of surfactants, modern directions of research in liquid crystals, and the key properties of foams. The book also explores the fundamental physics that controls the structure and mechanics of granular matter; how the unusual and often dramatic mechanical properties of concentrated polymer systems are determined by the physics of entanglements; the complex structures formed by block copolymers and the methods of structure analysis; rubber elasticity and new emerging classes of rubber-elastic materials; the physics of polyelectrolytes; the solvent dynamics in polymer gels, in equilibrium and under mechanical stress; the hierarchical structure and characteristics of an extracellular matrix; and the hierarchical structure and resulting physical properties of the cell cytoskeleton. The book concludes with an analysis of the properties of interfaces and membranes.
Book chapters on the topic "Active Granular Matter"
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Manacorda, Alessandro. "Theoretical Models of Granular and Active Matter." In Springer Theses, 31–66. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-95080-8_2.
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"Adaptive Granular Matter." In Active Matter. The MIT Press, 2017. http://dx.doi.org/10.7551/mitpress/11236.003.0044.
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"Rock Print: An Architectural Installation of Granular Matter." In Active Matter. The MIT Press, 2017. http://dx.doi.org/10.7551/mitpress/11236.003.0045.
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Ben Dor, Ydan, Yariv Kafri, and Julien Tailleur. "Forces in Dry Active Matter." In Active Matter and Nonequilibrium Statistical Physics, 591–621. Oxford University PressOxford, 2022. http://dx.doi.org/10.1093/oso/9780192858313.003.0016.
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Abstract This chapter introduces recent developments in the thermomechanics of active systems, which exhibit features that are very different from those of equilibrium systems. This has many implications for systems ranging from shaken granular gases to the motion of cells. We start with a short overview of different definitions of pressure and the conditions under which they are equivalent. This allows us to identify a class of systems – commonly referred to as dry active matter – where the simple equilibrium intuition might break. We show that there is, in general, no equation of state for the forces they exert on their container. We discuss the origin of this phenomenon, as well as its consequences. Finally, we go beyond the question of the equation of state and provide a brief discussion of recent developments concerning the forces exerted on objects immersed in active systems.
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Keitner, Chimène I. "Foreign Election Interference and International Law." In Defending Democracies, 179–96. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780197556979.003.0009.
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This chapter explores the possibilities, and limitations, of international law in regulating states’ attempts to influence each other’s elections. The principles of sovereignty, territorial integrity, political independence, self-determination, and nonintervention reflect core understandings about the attributes and entitlements of states in the international system. The chapter begins by tracing attempts to further codify the nonintervention principle in the 1960s and 1970s. It then examines the tension produced by states’ conflicting desires to preserve the greatest possible freedom of action for themselves and to constrain the behavior of others. To date, this dynamic has impeded the ability to formulate explicit treaty-based solutions to the problem of foreign election interference. Identifying customary international law in this area requires inferring specific conduct-regulating rules from general principles, which can yield contested results. States are unlikely to agree to more granular, binding international rules as long as regimes currently in power benefit from constructive ambiguity. Although agreement on more concrete rules and enforcement mechanisms might remain elusive, like-minded states should continue to emphasize the importance of supporting peoples’ abilities to determine their own political destinies. This requires, at a minimum, promoting an antideception norm as a matter of both domestic and international law.
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Santa, Kazuki. "Macrophages: Phagocytosis, Antigen Presentation, and Activation of Immunity." In Phagocytosis - Main Key of Immune System [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.110832.
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Macrophages are phagocytes and one of the white blood cells discovered by Ilya I. Mechnikov in 1892. They engulf and digest foreign substances like pathogens and conduct antigen presentation, mature from haematopoietic stem cells in bone marrow, moving into blood vessels and become monocytes, and differentiate into macrophages in the tissue. Macrophages have intracellular granules called lysosome accumulating digestive enzymes. Their life span is several months and proliferates by cell division. There are three roles: First one is phagocytosis. Macrophages incorporate pathogens and work in natural immunity. In inflammation, macrophages aggregate after neutrophils recruitment and engulf pathogens into cellular phagosomes, fused with lysosomes and degrade. Second role is antigen presentation. Macrophages present fragment of digested foreign substances on cell surface MHC class II molecules and release cytokines. Dendritic cells and B cells are also APCs expressing MHC class II. CD4+ T cells recognize antigens presented on macrophages by using TCR. Only well-matched helper T cells via MHC class II-TCR interaction are activated. The third is activation of immunity. Cytokines produced by T cells activate macrophages and differentiate them into inflammatory M1 and wound-healing M2 macrophages.
Conference papers on the topic "Active Granular Matter"
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Kerr, Vicki. "Performing nature unnaturally: Musique concrète and the performance of knowledge - one seabird at a time." In LINK 2021. Tuwhera Open Access, 2021. http://dx.doi.org/10.24135/link2021.v2i1.129.
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Migratory seabirds are an unseen conduit between marine and terrestrial systems, carrying the nutrients they consume at sea into the forests where they breed. Acting as environmental sentinels, their health and reproductive success provide early warning signals of deteriorating marine eco-systems as the climate changes, and fish stocks decrease. Aotearoa New Zealand is the seabird capital of the world, with ~25% of all species breeding here and ~10% exclusively so. They play a critical role in maintaining healthy ecosystems, with their long-term well-being is closely interconnected with our own prospects for a sustainable future. Now predominantly restricted to off-shore islands due to predation and habitat destruction, seabirds and their familiar sounds have become less available in an age when the unprecedented global movement and planetary spread of the human population has culminated in unsustainable fishing, predators and habitat destruction. Inspiring mythology, song, poetry and stories, birds have been significant in shaping our understanding of how our natural environment has come to be known and understood. This paper speculates upon how we learn to communicate and cooperate with these precious taonga, and what might be learned from such an exchange through creative practice. Reflecting upon what birds might tell us, musician Matthew Bannister and I, a visual artist, have taken our cue from seabirds sharing our local environment on the west coast of Aotearoa - from the petrel (peera) through to the gannet (tākapu). Working on the premise that bird vocalisation is a performed negotiation that includes defence of territory and mate attraction, a bird’s call is a form of communication that effectively says “Come here” or “Go away”, which arguably is true of music – marking a social space and time to invite or repel. Rather than limiting bird calls to functionalist categories of explanation, we ask whether seabirds can communicate and exchange information about environmental changes using a malleable vocabulary, comprised of unique acoustic units arranged and re-arranged sequentially for greater communicative depth. Granting a high level of agency and creativity to birds as opposed to believing a bird only avails itself of stereotyped ‘speech’ to survive an accident-rich environment, places greater importance on responses that are improvised directly upon environmental stimuli as irritant rather than as a signal. Matthew explores bird calls via musique concrète, sampling recordings of seabirds to abstract the musical values of bird song conventions – a human response to the ‘other’ in jointly formed compositions, reflecting a living evolving relationship between composer and bird. In further developing our research into a multimedia artwork, I shall extend a technique used for electroacoustic composition (granular synthesis) to video portraits of composer/performer and bird. In applying granular synthesis techniques to video, tiny units of image and sampled sound are reassembled within the frames. Through the mixing of existing synthesised sequences, performer/composer and bird become active participants in the making and remaking of a shared environment, articulating the limits of space/territory to find new ways to be heard within it.