Journal articles: 'Synthetic Active Matter'

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Lv, Chenglin, Yuguang Yang, and Bo Li. "Nano/Micromotors in Active Matter." Micromachines 13, no. 2 (2022): 307. http://dx.doi.org/10.3390/mi13020307.

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Nano/micromotors (NMMs) are tiny objects capable of converting energy into mechanical motion. Recently, a wealth of active matter including synthetic colloids, cytoskeletons, bacteria, and cells have been used to construct NMMs. The self-sustained motion of active matter drives NMMs out of equilibrium, giving rise to rich dynamics and patterns. Alongside the spontaneous dynamics, external stimuli such as geometric confinements, light, magnetic field, and chemical potential are also harnessed to control the movements of NMMs, yielding new application paradigms of active matter. Here, we review the recent advances, both experimental and theoretical, in exploring biological NMMs. The unique dynamical features of collective NMMs are focused on, along with some possible applications of these intriguing systems.

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Liebchen, Benno, and Hartmut Löwen. "Synthetic Chemotaxis and Collective Behavior in Active Matter." Accounts of Chemical Research 51, no. 12 (2018): 2982–90. http://dx.doi.org/10.1021/acs.accounts.8b00215.

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Takatori, Sho C., Titus Quah, and James B. Rawlings. "Feedback Control of Active Matter." Annual Review of Condensed Matter Physics 16, no. 1 (2025): 319–41. https://doi.org/10.1146/annurev-conmatphys-042424-043926.

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Feedback control is essential to the performance of dynamical systems, helping to drive nonequilibrium systems from one state to another. In this review, we discuss feedback control applied to living and synthetic active matter—systems that are constantly dynamical and out of equilibrium. We review the experimental and theoretical work in controlling the trajectory and distribution of active matter, from single particles to collective populations. Modern advances in microscopy and numerical computation have enabled data-rich studies of active systems, aided by data-driven approaches to model, forecast, and control the complex and chaotic behaviors of active matter. We describe the basic mathematical structure of active Brownian particles, with a focus on observability and time delay embedding to control particle motion using density data alone. Finally, we comment on the future outlook of controlling complex systems with multibody interparticle and hydrodynamic interactions.

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Chaté, Hugues. "Dry Aligning Dilute Active Matter." Annual Review of Condensed Matter Physics 11, no. 1 (2020): 189–212. http://dx.doi.org/10.1146/annurev-conmatphys-031119-050752.

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Active matter physics is about systems in which energy is dissipated at some local level to produce work. This is a generic situation, particularly in the living world but not only. What is at stake is the understanding of the fascinating, sometimes counterintuitive, emerging phenomena observed, from collective motion in animal groups to in vitro dynamical self-organization of motor proteins and biofilaments. Dry aligning dilute active matter (DADAM) is a corner of the multidimensional, fast-growing domain of active matter that has both historical and theoretical importance for the entire field. This restrictive setting only involves self-propulsion/activity, alignment, and noise, yet unexpected collective properties can emerge from it. This review provides a personal but synthetic and coherent overview of DADAM, focusing on the collective-level phenomenology of simple active particle models representing basic classes of systems and on the solutions of the continuous hydrodynamic theories that can be derived from them. The obvious fact that orientational order is advected by the aligning active particles at play is shown to be at the root of the most striking properties of DADAM systems: ( a) direct transitions to orientational order are not observed; ( b) instead generic phase separation occurs with a coexistence phase involving inhomogeneous nonlinear structures; ( c) orientational order, which can be long range even in two dimensions, is accompanied by long-range correlations and anomalous fluctuations; ( d) defects are not point-like, topologically bound objects.

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Puziy, A. M. "Heterogeneity of Synthetic Active Carbons." Langmuir 11, no. 2 (1995): 543–46. http://dx.doi.org/10.1021/la00002a030.

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Anderson, C., and A. Fernandez-Nieves. "Active many-particle systems and the emergent behavior of dense ant collectives." Reports on Progress in Physics 87, no. 6 (2024): 066602. http://dx.doi.org/10.1088/1361-6633/ad49b4.

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Abstract This article discusses recent work with fire ants, Solenopisis invicta, to illustrate the use of the framework of active matter as a base to rationalize their complex collective behavior. We review much of the work that physicists have done on the group dynamics of these ants, and compare their behavior to two minimal models of active matter, and to the behavior of the synthetic systems that have served to test and drive these models.

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Saad, Shabab, and Giovanniantonio Natale. "Diffusiophoresis of active colloids in viscoelastic media." Soft Matter 15, no. 48 (2019): 9909–19. http://dx.doi.org/10.1039/c9sm01801h.

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Chardac, Amélie, Suraj Shankar, M. Cristina Marchetti, and Denis Bartolo. "Emergence of dynamic vortex glasses in disordered polar active fluids." Proceedings of the National Academy of Sciences 118, no. 10 (2021): e2018218118. http://dx.doi.org/10.1073/pnas.2018218118.

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In equilibrium, disorder conspires with topological defects to redefine the ordered states of matter in systems as diverse as crystals, superconductors, and liquid crystals. Far from equilibrium, however, the consequences of quenched disorder on active condensed matter remain virtually uncharted. Here, we reveal a state of strongly disordered active matter with no counterparts in equilibrium: a dynamical vortex glass. Combining microfluidic experiments and theory, we show how colloidal flocks collectively cruise through disordered environments without relaxing the topological singularities of their flows. The resulting state is highly dynamical but the flow patterns, shaped by a finite density of frozen vortices, are stationary and exponentially degenerated. Quenched isotropic disorder acts as a random gauge field turning active liquids into dynamical vortex glasses. We argue that this robust mechanism should shape the collective dynamics of a broad class of disordered active matter, from synthetic active nematics to collections of living cells exploring heterogeneous media.

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Weber, Christoph A., Ryo Suzuki, Volker Schaller, Igor S. Aranson, Andreas R. Bausch, and Erwin Frey. "Random bursts determine dynamics of active filaments." Proceedings of the National Academy of Sciences 112, no. 34 (2015): 10703–7. http://dx.doi.org/10.1073/pnas.1421322112.

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Constituents of living or synthetic active matter have access to a local energy supply that serves to keep the system out of thermal equilibrium. The statistical properties of such fluctuating active systems differ from those of their equilibrium counterparts. Using the actin filament gliding assay as a model, we studied how nonthermal distributions emerge in active matter. We found that the basic mechanism involves the interplay between local and random injection of energy, acting as an analog of a thermal heat bath, and nonequilibrium energy dissipation processes associated with sudden jump-like changes in the system’s dynamic variables. We show here how such a mechanism leads to a nonthermal distribution of filament curvatures with a non-Gaussian shape. The experimental curvature statistics and filament relaxation dynamics are reproduced quantitatively by stochastic computer simulations and a simple kinetic model.

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Santiago, Ibon, and Friedrich C. Simmel. "Self-Propulsion Strategies for Artificial Cell-Like Compartments." Nanomaterials 9, no. 12 (2019): 1680. http://dx.doi.org/10.3390/nano9121680.

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Reconstitution of life-like properties in artificial cells is a current research frontier in synthetic biology. Mimicking metabolism, growth, and sensing are active areas of investigation; however, achieving motility and directional taxis are also challenging in the context of artificial cells. To tackle this problem, recent progress has been made that leverages the tools of active matter physics in synthetic biology. This review surveys the most significant achievements in designing motile cell-like compartments. In this context, strategies for self-propulsion are summarized, including, compartmentalization of catalytically active particles, phoretic propulsion of vesicles and emulsion droplet motion driven by Marangoni flows. This work showcases how the realization of motile protocells may impact biomedical engineering while also aiming at answering fundamental questions in locomotion of prebiotic cells.

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Thampi, Sumesh P., Amin Doostmohammadi, Tyler N. Shendruk, Ramin Golestanian, and Julia M. Yeomans. "Active micromachines: Microfluidics powered by mesoscale turbulence." Science Advances 2, no. 7 (2016): e1501854. http://dx.doi.org/10.1126/sciadv.1501854.

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Dense active matter, from bacterial suspensions and microtubule bundles driven by motor proteins to cellular monolayers and synthetic Janus particles, is characterized by mesoscale turbulence, which is the emergence of chaotic flow structures. By immersing an ordered array of symmetric rotors in an active fluid, we introduce a microfluidic system that exploits spontaneous symmetry breaking in mesoscale turbulence to generate work. The lattice of rotors self-organizes into a spin state where neighboring discs continuously rotate in permanent alternating directions due to combined hydrodynamic and elastic effects. Our virtual prototype demonstrates a new research direction for the design of micromachines powered by the nematohydrodynamic properties of active turbulence.

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Reigh, Shang Yik, Mu-Jie Huang, Hartmut Löwen, Eric Lauga, and Raymond Kapral. "Active rotational dynamics of a self-diffusiophoretic colloidal motor." Soft Matter 16, no. 5 (2020): 1236–45. http://dx.doi.org/10.1039/c9sm01977d.

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The dynamics of a spherical chemically-powered synthetic colloidal motor that operates by a self-diffusiophoretic mechanism and has a catalytic domain of arbitrary shape is studied using both continuum theory and particle-based simulations.

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Wang, Wei, Xianglong Lv, Jeffrey L. Moran, Shifang Duan, and Chao Zhou. "A practical guide to active colloids: choosing synthetic model systems for soft matter physics research." Soft Matter 16, no. 16 (2020): 3846–68. http://dx.doi.org/10.1039/d0sm00222d.

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DANDOIS, JULIEN, ERIC GARNIER, and PIERRE SAGAUT. "Numerical simulation of active separation control by a synthetic jet." Journal of Fluid Mechanics 574 (February 15, 2007): 25–58. http://dx.doi.org/10.1017/s0022112006003995.

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Direct numerical simulation (DNS) and large-eddy simulation (LES) are carried out to investigate the frequency effect of zero-net-mass-flux forcing (synthetic jet) on a generic separated flow. The selected test case is a rounded ramp at a Reynolds number based on the step height of 28 275. The incoming boundary layer is fully turbulent withRθ=1410. The whole flow in the synthetic jet cavity is computed to ensure an accurate description of the actuator effect on the flow field. In a first step, DNS is used to validate LES of this particular flow. In a second step, the effect of a synthetic jet at two reduced frequencies of 0.5 and 4 (based on the separation length of the uncontrolled case and the free-stream velocity) is investigated using LES. It is demonstrated that, with a proper choice of the oscillating frequency, separation can be drastically reduced for a velocity ratio between the jet and the flow lower than one. The low frequency is close to the natural vortex shedding frequency. Two different modes of the synthetic jet have been identified. Avorticity-dominated modeis observed in the low-frequency forcing case for which the separation length is reduced by 54%, while anacoustic-dominated modeis identified in the high-frequency forcing case for which the separation length is increased by 43%. The decrease of the separation length in the low-frequency forcing case is correlated with an increase of the turbulent kinetic energy level and consequently with an increase of the entrainment in the separated zone. A linear inviscid stability analysis shows that the increase of the separation length in the high-frequency forcing case is due to a modification of the mean velocity profile suggested by Stanek and coworkers. The result is a lower amplification of the perturbations and consequently, a lower entrainment into the mixing layer. To our knowledge, it is the first time that Stanek's hypothesis has been assessed, thanks to numerical simulations of fully turbulent flow.

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Dinges, Laslo, Ayoub Al-Hamadi, Moftah Elzobi, Sherif El-etriby, and Ahmed Ghoneim. "ASM Based Synthesis of Handwritten Arabic Text Pages." Scientific World Journal 2015 (2015): 1–18. http://dx.doi.org/10.1155/2015/323575.

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Document analysis tasks, as text recognition, word spotting, or segmentation, are highly dependent on comprehensive and suitable databases for training and validation. However their generation is expensive in sense of labor and time. As a matter of fact, there is a lack of such databases, which complicates research and development. This is especially true for the case of Arabic handwriting recognition, that involves different preprocessing, segmentation, and recognition methods, which have individual demands on samples and ground truth. To bypass this problem, we present an efficient system that automatically turns Arabic Unicode text into synthetic images of handwritten documents and detailed ground truth. Active Shape Models (ASMs) based on 28046 online samples were used for character synthesis and statistical properties were extracted from the IESK-arDB database to simulate baselines and word slant or skew. In the synthesis step ASM based representations are composed to words and text pages, smoothed by B-Spline interpolation and rendered considering writing speed and pen characteristics. Finally, we use the synthetic data to validate a segmentation method. An experimental comparison with the IESK-arDB database encourages to train and test document analysis related methods on synthetic samples, whenever no sufficient natural ground truthed data is available.

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Liebchen, Benno, and Aritra K. Mukhopadhyay. "Interactions in active colloids." Journal of Physics: Condensed Matter 34, no. 8 (2021): 083002. http://dx.doi.org/10.1088/1361-648x/ac3a86.

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Abstract The past two decades have seen a remarkable progress in the development of synthetic colloidal agents which are capable of creating directed motion in an unbiased environment at the microscale. These self-propelling particles are often praised for their enormous potential to self-organize into dynamic nonequilibrium structures such as living clusters, synchronized super-rotor structures or self-propelling molecules featuring a complexity which is rarely found outside of the living world. However, the precise mechanisms underlying the formation and dynamics of many of these structures are still barely understood, which is likely to hinge on the gaps in our understanding of how active colloids interact. In particular, besides showing comparatively short-ranged interactions which are well known from passive colloids (Van der Waals, electrostatic etc), active colloids show novel hydrodynamic interactions as well as phoretic and substrate-mediated ‘osmotic’ cross-interactions which hinge on the action of the phoretic field gradients which are induced by the colloids on other colloids in the system. The present article discusses the complexity and the intriguing properties of these interactions which in general are long-ranged, non-instantaneous, non-pairwise and non-reciprocal and which may serve as key ingredients for the design of future nonequilibrium colloidal materials. Besides providing a brief overview on the state of the art of our understanding of these interactions a key aim of this review is to emphasize open key questions and corresponding open challenges.

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Han, Koohee, Gašper Kokot, Oleh Tovkach, Andreas Glatz, Igor S. Aranson, and Alexey Snezhko. "Emergence of self-organized multivortex states in flocks of active rollers." Proceedings of the National Academy of Sciences 117, no. 18 (2020): 9706–11. http://dx.doi.org/10.1073/pnas.2000061117.

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Active matter, both synthetic and biological, demonstrates complex spatiotemporal self-organization and the emergence of collective behavior. A coherent rotational motion, the vortex phase, is of great interest because of its ability to orchestrate well-organized motion of self-propelled particles over large distances. However, its generation without geometrical confinement has been a challenge. Here, we show by experiments and computational modeling that concentrated magnetic rollers self-organize into multivortex states in an unconfined environment. We find that the neighboring vortices more likely occur with the opposite sense of rotation. Our studies provide insights into the mechanism for the emergence of coherent collective motion on the macroscale from the coupling between microscale rotation and translation of individual active elements. These results may stimulate design strategies for self-assembled dynamic materials and microrobotics.

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Furumai, Hiroaki, Takahiro Kuba, Tsuyoshi Imai, and Tetsuya Kusuda. "Transient Responses of Wastewater Treatment and Biomass Development in a Methanogenic Fluidized Bed." Water Science and Technology 23, no. 7-9 (1991): 1327–36. http://dx.doi.org/10.2166/wst.1991.0585.

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The objectives of this study are to develop a model which can express the characteristics of anaerobic treatment in a methanogenic fluidized bed reactor in non-steady states, and evaluate the usefulness of the model in which “active” biomass concentration is used as an index of bacteria concentration instead of traditional ones such as volatile suspended solids. The treatment in the fluidized bed reactor started with biocoated synthetic zeolite as support material. The reactor was supplied with synthetic wastewater, a mixture of volatile fatty acids. An experiment on response was conducted according to changing stepwise the influent concentration. Batch experiments on activity were carried out under several steady state conditions, using a kind of volatile fatty acid as a substrate. Transient responses of water quality are investigated in relation to the growth of bacterial groups which decompose volatile fatty acids. Based on the results, a dynamic model is proposed, in which attached biomass is categorized into “active” biomass and inert organic matter. The transient response of substrate concentrations was clearly expressed by considering the growth of “active” biomass. It was impossible to explain the responses when VSS was regarded as the biomass concentration in the model.

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Pavlova, Anna A., Kiyoshi Otani, and Michael Amitay. "Active control of sprays using a single synthetic jet actuator." International Journal of Heat and Fluid Flow 29, no. 1 (2008): 131–48. http://dx.doi.org/10.1016/j.ijheatfluidflow.2007.06.004.

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Tamburello, David A., and Michael Amitay. "Active control of a free jet using a synthetic jet." International Journal of Heat and Fluid Flow 29, no. 4 (2008): 967–84. http://dx.doi.org/10.1016/j.ijheatfluidflow.2008.02.017.

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Ion, Ion, Raluca Madalina Senin, Bogdan Vasile, and Alina Catrinel Ion. "INFLUENCE OF THE MATRIX OF AQUEOUS SOLUTIONS ON THE ADSORPTION OF ENDOCRINE DISRUPTORS BY FULLERENE C60." Journal of Environmental Engineering and Landscape Management 27, no. 1 (2019): 1–11. http://dx.doi.org/10.3846/jeelm.2019.7644.

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In this work, fullerene (C60) was selected as a model carbon nanomaterial, humic acid (HA) as the model natural organic matter and bisphenol A (BPA), as a moderate hydrophobic organic contaminant. The effects of ionic strength, concentration of organic matter and of the pH over the adsorption of BPA on C60 were studied, as well as the competition between the BPA and the HA at the active sites of the C60. A possible adsorption mechanism was proposed as well as an attempt to study the sorption process in real environmental samples with characteristics alike to the optimum ones found in the synthetic samples studied.

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Crow, Steven C., and Gene G. Bergmeier. "Active sonic boom control." Journal of Fluid Mechanics 325 (October 25, 1996): 1–28. http://dx.doi.org/10.1017/s0022112096008014.

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A theory and simulation code are developed to study non-steady sources as means to control sonic booms of supersonic aircraft. A key result is that the source of sonic boom pressure is not confined to the length of the aircraft but occupies an extensive segment of the flight path. An aircraft in non-steady flight functions as a synthetic aperture antenna, generating complex acoustic waves with no simple relation to instantaneous volume or lift distributions.The theory applies linear acoustics to slender non-steady sources but requires no far-field approximation. The solution for pressure contains a term not seen in Whitham's theory for sonic booms of distant supersonic aircraft. The term describes a pressure field that decays algebraically behind the Mach cone and, in the case of steady flight, integrates to a ground load equal to the weight of the aircraft. The algebraic term is separate from those that describe the sonic boom.Two non-steady source phenomena are evaluated: periodic velocity changes (surge), and periodic longitudinal lift redistribution (slosh). Surge can attenuate a sonic boom and covert it into prolonged weak reverberation, but accelerations needed to produce the phenomenon seem too large for practical use. Slosh may be practical and can alter sonic booms but does not, on average, result in boom attenuation. The conclusion is that active sonic boom abatement is possible in theory but maybe not practical.

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РЯБУШКИНА, Татьяна Михайловна. "СУБЪЕКТ ВОСПРИЯТИЯ: СООТНОШЕНИЕ АКТИВНОСТИ И ПАССИВНОСТИ". Гуманитарные исследования в Восточной Сибири и на Дальнем Востоке, № 4 (13 грудня 2023): 145–56. http://dx.doi.org/10.24866/1997-2857/2023-4/145-156.

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The article presents a critical analysis of the transcendental-phenomenological understanding of perception as a result of the active synthetic activity of the subject, aimed at the «matter» of experience acquired through passivity. This subjectivist view is compared with the phenomenological description of perception as being-in-the-world on the basis of ideas about embodiment and temporality. The author attempts to resolve the difficulties of these approaches by taking into consideration the preconscious process of cognition as a necessary condition for the possibility of conscious perceptions.

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Kim, Hyunki, Subramanian Sundaram, Ji-Hwan Kang, Nabila Tanjeem, Todd Emrick, and Ryan C. Hayward. "Coupled oscillation and spinning of photothermal particles in Marangoni optical traps." Proceedings of the National Academy of Sciences 118, no. 18 (2021): e2024581118. http://dx.doi.org/10.1073/pnas.2024581118.

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Cyclic actuation is critical for driving motion and transport in living systems, ranging from oscillatory motion of bacterial flagella to the rhythmic gait of terrestrial animals. These processes often rely on dynamic and responsive networks of oscillators—a regulatory control system that is challenging to replicate in synthetic active matter. Here, we describe a versatile platform of light-driven active particles with interaction geometries that can be reconfigured on demand, enabling the construction of oscillator and spinner networks. We employ optically induced Marangoni trapping of particles confined to an air–water interface and subjected to patterned illumination. Thermal interactions among multiple particles give rise to complex coupled oscillatory and rotational motions, thus opening frontiers in the design of reconfigurable, multiparticle networks exhibiting collective behavior.

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Sandoval, Mario, Navaneeth K. Marath, Ganesh Subramanian, and Eric Lauga. "Stochastic dynamics of active swimmers in linear flows." Journal of Fluid Mechanics 742 (February 21, 2014): 50–70. http://dx.doi.org/10.1017/jfm.2013.651.

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AbstractMost classical work on the hydrodynamics of low-Reynolds-number swimming addresses deterministic locomotion in quiescent environments. Thermal fluctuations in fluids are known to lead to a Brownian loss of the swimming direction, resulting in a transition from short-time ballistic dynamics to effective long-time diffusion. As most cells or synthetic swimmers are immersed in external flows, we consider theoretically in this paper the stochastic dynamics of a model active particle (a self-propelled sphere) in a steady general linear flow. The stochasticity arises both from translational diffusion in physical space, and from a combination of rotary diffusion and so-called run-and-tumble dynamics in orientation space. The latter process characterizes the manner in which the orientation of many bacteria decorrelates during their swimming motion. In contrast to rotary diffusion, the decorrelation occurs by means of large and impulsive jumps in orientation (tumbles) governed by a Poisson process. We begin by deriving a general formulation for all components of the long-time mean square displacement tensor for a swimmer with a time-dependent swimming velocity and whose orientation decorrelates due to rotary diffusion alone. This general framework is applied to obtain the convectively enhanced mean-squared displacements of a steadily swimming particle in three canonical linear flows (extension, simple shear and solid-body rotation). We then show how to extend our results to the case where the swimmer orientation also decorrelates on account of run-and-tumble dynamics. Self-propulsion in general leads to the same long-time temporal scalings as for passive particles in linear flows but with increased coefficients. In the particular case of solid-body rotation, the effective long-time diffusion is the same as that in a quiescent fluid, and we clarify the lack of flow dependence by briefly examining the dynamics in elliptic linear flows. By comparing the new active terms with those obtained for passive particles we see that swimming can lead to an enhancement of the mean-square displacements by orders of magnitude, and could be relevant for biological organisms or synthetic swimming devices in fluctuating environmental or biological flows.

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Romensky, Maksym, Dimitri Scholz, and Vladimir Lobaskin. "Hysteretic dynamics of active particles in a periodic orienting field." Journal of The Royal Society Interface 12, no. 108 (2015): 20150015. http://dx.doi.org/10.1098/rsif.2015.0015.

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Active motion of living organisms and artificial self-propelling particles has been an area of intense research at the interface of biology, chemistry and physics. Significant progress in understanding these phenomena has been related to the observation that dynamic self-organization in active systems has much in common with ordering in equilibrium condensed matter such as spontaneous magnetization in ferromagnets. The velocities of active particles may behave similar to magnetic dipoles and develop global alignment, although interactions between the individuals might be completely different. In this work, we show that the dynamics of active particles in external fields can also be described in a way that resembles equilibrium condensed matter. It follows simple general laws, which are independent of the microscopic details of the system. The dynamics is revealed through hysteresis of the mean velocity of active particles subjected to a periodic orienting field. The hysteresis is measured in computer simulations and experiments on unicellular organisms. We find that the ability of the particles to follow the field scales with the ratio of the field variation period to the particles' orientational relaxation time, which, in turn, is related to the particle self-propulsion power and the energy dissipation rate. The collective behaviour of the particles due to aligning interactions manifests itself at low frequencies via increased persistence of the swarm motion when compared with motion of an individual. By contrast, at high field frequencies, the active group fails to develop the alignment and tends to behave like a set of independent individuals even in the presence of interactions. We also report on asymptotic laws for the hysteretic dynamics of active particles, which resemble those in magnetic systems. The generality of the assumptions in the underlying model suggests that the observed laws might apply to a variety of dynamic phenomena from the motion of synthetic active particles to crowd or opinion dynamics.

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Liu, Baolin, Yizhao Li, Shaojun Qing, Kun Wang, Jing Xie, and Yali Cao. "Engineering CuOx–ZrO2–CeO2 nanocatalysts with abundant surface Cu species and oxygen vacancies toward high catalytic performance in CO oxidation and 4-nitrophenol reduction." CrystEngComm 22, no. 23 (2020): 4005–13. http://dx.doi.org/10.1039/d0ce00588f.

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CuOx–ZrO2–CeO2 nanocrystalline catalysts were designed and synthesized by a solvent-free synthetic strategy, and exhibited excellent catalytic performance owing to the increased oxygen vacancies and better dispersed active metal species.

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Igbashio, M.D, and E.I. Obasuyi. "Production of Local Soap Using Alkali Derived from Mango and Plantain Peel." NIPES Journal of Science and Technology Research 4, no. 4 (2022): 90–95. https://doi.org/10.5281/zenodo.7395753.

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Local soap was produced using mango and plantain peels as an active ingredient. The mango and plantain peels are agricultural-wastes matter that litter the environment. This study made use of mango and plantain peel ashes as a cheap alternative source of alkali that is much needed in soap making. The agricultural waste materials were burnt and the ashes were used to prepare a solution of potassium hydroxide (KOH), which was heated alongside palm kernel oil (PKO) until soap was formed. The quality of the soap was assessed thus: The colour:dark-brown, the texture: soft, the foamability: good, the foam size: small, and Foam stability: stable. The physicochemical parameters of the soap were also assessed thus; Total Fatty Matter: 62.42%, Total Free Alkali: 6.40%, Free Caustic Alkali: 2.97%, Wash Active Substance: 34.98%, and pH: 10.02. These assessments revealed that the alkali derived from mango and plantain peels is a good and cheap active ingredient for soap production. The exploitation of alkali derived from agricultural waste materials for the making of soap is worthwhile. This would also prevent environmental pollution by these waste materials that might potentially cause harm to the populace, and also reduce over dependence on synthetic alkali for soap production and also provide an alternative source of income

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Lozano, José Manuel, Luz Mary Salazar, Ángela Torres, et al. "COVID-19 Infection Detection and Prevention by SARS-CoV-2 Active Antigens: A Synthetic Vaccine Approach." Vaccines 8, no. 4 (2020): 692. http://dx.doi.org/10.3390/vaccines8040692.

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COVID-19, a global pandemic causing to date more than 50 million cases and more than a million deaths, has to be controlled. SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) was identified as the causative agent. Controversy about this virus origin and infectious mechanism for adapting to humans remains a matter for discussion. Among all strategies for obtaining safe and potent vaccines, approaches based on attenuated-killed virus and non-replicating RNA viral vectors are demonstrating promising results. However, specificity of viral components targeted by human antibodies so far has not been demonstrated. A consistent strategy for obtaining functional-active antigens from SARS-CoV-2 specific ligands lead us to propose and test a number of synthetic components. From hundreds of starting sequences only fifteen fulfilled the design requirements and were produced as monomer and polymer forms and immuno-chemically tested. The design was based on worldwide representative reported virus genomes. A bioinformatics scheme by conventional methods and knowledge on MHC-I and II antigen processing mechanisms and HLA haplotype-restriction was performed including sensitive and resistant human populations to virus infection. Covid-19 patients’ sera reactivity for synthetic SARS-CoV-2-designed components have proven a high recognition of specific molecules, as well as some evidence for a long-lasting humoral immune response.

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Lee, Chester, Guang Hong, Q. P. Ha, and S. G. Mallinson. "A piezoelectrically actuated micro synthetic jet for active flow control." Sensors and Actuators A: Physical 108, no. 1-3 (2003): 168–74. http://dx.doi.org/10.1016/s0924-4247(03)00267-x.

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Reháková, Mária, Mario Casciola, Silvia Čuvanová, et al. "Nanosized composites of synthetic zeolites and silver iodide as potentially electrochemically active materials." Journal of Inclusion Phenomena and Macrocyclic Chemistry 66, no. 3-4 (2009): 319–25. http://dx.doi.org/10.1007/s10847-009-9647-1.

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Beppu, Kazusa, Ziane Izri, Yusuke Maeda, and Ryota Sakamoto. "Geometric Effect for Biological Reactors and Biological Fluids." Bioengineering 5, no. 4 (2018): 110. http://dx.doi.org/10.3390/bioengineering5040110.

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As expressed “God made the bulk; the surface was invented by the devil” by W. Pauli, the surface has remarkable properties because broken symmetry in surface alters the material properties. In biological systems, the smallest functional and structural unit, which has a functional bulk space enclosed by a thin interface, is a cell. Cells contain inner cytosolic soup in which genetic information stored in DNA can be expressed through transcription (TX) and translation (TL). The exploration of cell-sized confinement has been recently investigated by using micron-scale droplets and microfluidic devices. In the first part of this review article, we describe recent developments of cell-free bioreactors where bacterial TX-TL machinery and DNA are encapsulated in these cell-sized compartments. Since synthetic biology and microfluidics meet toward the bottom-up assembly of cell-free bioreactors, the interplay between cellular geometry and TX-TL advances better control of biological structure and dynamics in vitro system. Furthermore, biological systems that show self-organization in confined space are not limited to a single cell, but are also involved in the collective behavior of motile cells, named active matter. In the second part, we describe recent studies where collectively ordered patterns of active matter, from bacterial suspensions to active cytoskeleton, are self-organized. Since geometry and topology are vital concepts to understand the ordered phase of active matter, a microfluidic device with designed compartments allows one to explore geometric principles behind self-organization across the molecular scale to cellular scale. Finally, we discuss the future perspectives of a microfluidic approach to explore the further understanding of biological systems from geometric and topological aspects.

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Dobrowolska, Bogusława, Tomasz Dorożyński, and Anetta Kuna‑Marszałek. "Does Governance Matter for Outward FDI? Evidence from the European Union Member States." Comparative Economic Research. Central and Eastern Europe 27, no. 4 (2024): 67–87. https://doi.org/10.18778/1508-2008.27.31.

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Our principal aim is to assess the role of governance companies’ active internationalisation. We first measured and compared the degree of institutional quality among the 28 European Union Member States (EU–28) between 2004 and 2021 using the authorship synthetic index of governance quality (SIGQ) values. In the second step, we assessed outward foreign direct investment (OFDI) projects measured by their relative value to the GDP per capita in each member state. Finally, we correlated the overall quality of governance (GQ) and its six dimensions with OFDI in the EU–28 (including the UK). We employed numerous statistical tools, i.e., hierarchical cluster analysis, contingency analysis, synthetic index values, and descriptive statistics. We used the Worldwide Governance Index (WGI) to assess the GQ in the EU–28 for 2004–2021. The statistical analysis results revealed a positive relationship between the quality of governance and the OFDI. The most important of the partial variables was the rule of law, which reflects perceptions of the degree to which individuals and actors trust and adhere to social rules. Our research demonstrates that policymakers should consider the importance of institutional quality indicators in supporting domestic companies “to go abroad”. The primary input delivered by the study to the current body of knowledge about OFDI involves identifying the relationship between GQ in all the EU–28 (“old” and “new”) using the SIGQ index.

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Wang, Chenglei, Hui Tang, Simon C. M. Yu, and Fei Duan. "Control of vortex-induced vibration using a pair of synthetic jets: Influence of active lock-on." Physics of Fluids 29, no. 8 (2017): 083602. http://dx.doi.org/10.1063/1.4996231.

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Tzuang, Ching-Kuang C., Hsien-Hung Wu, Hsien-Shun Wu, and Johnsea Chen. "CMOS Active Bandpass Filter Using Compacted Synthetic Quasi-TEM Lines at $C$-Band." IEEE Transactions on Microwave Theory and Techniques 54, no. 12 (2006): 4548–55. http://dx.doi.org/10.1109/tmtt.2006.881507.

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Khurshid, Asma, Aamer Saeed, Tuncer Hökelek, et al. "Experimental and Hirshfeld Surface Investigations for Unexpected Aminophenazone Cocrystal Formation under Thiourea Reaction Conditions via Possible Enamine Assisted Rearrangement." Crystals 12, no. 5 (2022): 608. http://dx.doi.org/10.3390/cryst12050608.

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Considering the astounding biomedicine properties of pharmaceutically active drug, 4-aminophenazone, also known as 4-aminoantipyrine, the work reported in this manuscript details the formation of novel cocrystals of rearranged 4-aminophenazone and 4-nitro-N-(4-nitrobenzoyl) benzamide in 1:1 stoichiometry under employed conditions for thiourea synthesis by exploiting the use of its active amino component. However, detailed analysis via various characterization techniques such as FT-IR, nuclear magnetic resonance spectroscopy and single crystal XRD, for this unforeseen, but useful cocrystalline synthetic adduct (4 and 5) prompted us to delve into its mechanistic pathway under provided reaction conditions. The coformer 4-nitro-N-(4-nitrobenzoyl) benzamide originates via nucleophilic addition reaction following tetrahedral mechanism between para-nitro substituted benzoyl amide and its acid halide (1). While the enamine nucleophilic addition reaction by 4-aminophenazone on 4-nitrosubstituted aroyl isothiocyanates under reflux temperature suggests the emergence of rearranged counterpart of cocrystal named N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carbonothioyl)-4-nitrobenzamide. Crystallographic studies reveal triclinic system P-1 space group for cocrystal (4 and 5) and depicts two different crystallographically independent molecules with prominent C–H···O and N–H···O hydrogen bonding effective for structure stabilization. Hirshfeld surface analysis also displays hydrogen bonding and van der Waals interactions as dominant interactions in crystal packing. Further insight into the cocrystal synthetic methodologies supported the occurrence of solution-based evaporation/cocrystallization methodology in our case during purification step, promoting the synthesis of this first-ever reported novel cocrystal of 4-aminophenazone with promising future application in medicinal industry.

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Khurshid, Asma, Aamer Saeed, Tuncer Hökelek, et al. "Experimental and Hirshfeld Surface Investigations for Unexpected Aminophenazone Cocrystal Formation under Thiourea Reaction Conditions via Possible Enamine Assisted Rearrangement." Crystals 12, no. 5 (2022): 608. http://dx.doi.org/10.3390/cryst12050608.

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Considering the astounding biomedicine properties of pharmaceutically active drug, 4-aminophenazone, also known as 4-aminoantipyrine, the work reported in this manuscript details the formation of novel cocrystals of rearranged 4-aminophenazone and 4-nitro-N-(4-nitrobenzoyl) benzamide in 1:1 stoichiometry under employed conditions for thiourea synthesis by exploiting the use of its active amino component. However, detailed analysis via various characterization techniques such as FT-IR, nuclear magnetic resonance spectroscopy and single crystal XRD, for this unforeseen, but useful cocrystalline synthetic adduct (4 and 5) prompted us to delve into its mechanistic pathway under provided reaction conditions. The coformer 4-nitro-N-(4-nitrobenzoyl) benzamide originates via nucleophilic addition reaction following tetrahedral mechanism between para-nitro substituted benzoyl amide and its acid halide (1). While the enamine nucleophilic addition reaction by 4-aminophenazone on 4-nitrosubstituted aroyl isothiocyanates under reflux temperature suggests the emergence of rearranged counterpart of cocrystal named N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carbonothioyl)-4-nitrobenzamide. Crystallographic studies reveal triclinic system P-1 space group for cocrystal (4 and 5) and depicts two different crystallographically independent molecules with prominent C–H···O and N–H···O hydrogen bonding effective for structure stabilization. Hirshfeld surface analysis also displays hydrogen bonding and van der Waals interactions as dominant interactions in crystal packing. Further insight into the cocrystal synthetic methodologies supported the occurrence of solution-based evaporation/cocrystallization methodology in our case during purification step, promoting the synthesis of this first-ever reported novel cocrystal of 4-aminophenazone with promising future application in medicinal industry.

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38

Khurshid, Asma, Aamer Saeed, Tuncer Hökelek, et al. "Experimental and Hirshfeld Surface Investigations for Unexpected Aminophenazone Cocrystal Formation under Thiourea Reaction Conditions via Possible Enamine Assisted Rearrangement." Crystals 12, no. 5 (2022): 608. http://dx.doi.org/10.3390/cryst12050608.

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Considering the astounding biomedicine properties of pharmaceutically active drug, 4-aminophenazone, also known as 4-aminoantipyrine, the work reported in this manuscript details the formation of novel cocrystals of rearranged 4-aminophenazone and 4-nitro-N-(4-nitrobenzoyl) benzamide in 1:1 stoichiometry under employed conditions for thiourea synthesis by exploiting the use of its active amino component. However, detailed analysis via various characterization techniques such as FT-IR, nuclear magnetic resonance spectroscopy and single crystal XRD, for this unforeseen, but useful cocrystalline synthetic adduct (4 and 5) prompted us to delve into its mechanistic pathway under provided reaction conditions. The coformer 4-nitro-N-(4-nitrobenzoyl) benzamide originates via nucleophilic addition reaction following tetrahedral mechanism between para-nitro substituted benzoyl amide and its acid halide (1). While the enamine nucleophilic addition reaction by 4-aminophenazone on 4-nitrosubstituted aroyl isothiocyanates under reflux temperature suggests the emergence of rearranged counterpart of cocrystal named N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carbonothioyl)-4-nitrobenzamide. Crystallographic studies reveal triclinic system P-1 space group for cocrystal (4 and 5) and depicts two different crystallographically independent molecules with prominent C–H···O and N–H···O hydrogen bonding effective for structure stabilization. Hirshfeld surface analysis also displays hydrogen bonding and van der Waals interactions as dominant interactions in crystal packing. Further insight into the cocrystal synthetic methodologies supported the occurrence of solution-based evaporation/cocrystallization methodology in our case during purification step, promoting the synthesis of this first-ever reported novel cocrystal of 4-aminophenazone with promising future application in medicinal industry.

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Wakhungu, N. Cynthia. "Loss of soil biodiversity through judicious use of synthetic pesticides, A case study of trans-Nzoia County Kenya-review." Scientific Reports in Life Sciences 4, no. 4 (2024): 1–24. https://doi.org/10.5281/zenodo.10492764.

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Trans Nzoia County is one of Kenya’s leading food basket regions and enjoys favorable climatic conditions for crop production. With climatic change, farmers face challenges of soil infertility and pest and disease infestation, contributing to crop yield losses. Trans Nzoia County farmers rely heavily on synthetic pesticides to boost crop production and yields. In Kenya, 44% of the chemical pesticides used are banned in the EU market. Of these, 76% of the total volume sold contains active ingredients such as glyphosate, mancozeb, and paraquat, categorized as highly hazardous pesticides. Pesticide-intensive agriculture is on the rise in Trans Nzoia County, and the associated pollution are the driving factor in the precipitous decline of soil biodiversity, such as ground-nesting bees and beetles. Also, overreliance on synthetic pesticides contributes to the loss of beneficial soil microorganisms such as mycorrhizal species and earthworms responsible for nitrogen fixation, organic matter decomposition, and water and nutrient absorption. The author provides insights into the extent of the loss of beneficial soil organisms through synthetic pesticides. This review discusses the impacts and costs of pesticide use on soil organisms and policy responses.

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Ismagulova, N. M., Zh S. Nurmaganbetov, A. Zh Turmukhambetov, T. S. Seitembetov, and S. M. Adekenov. "Synthetic Derivatives of Natural Alkaloid Harmine." Eurasian Chemico-Technological Journal 11, no. 3 (2016): 199. http://dx.doi.org/10.18321/ectj281.

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The indole alkaloid harmine was extracted from underground part of Peganum harmala L. With the purpose of obtaining the new biological active derivatives on base of alkaloid harmine the chemical modification was carried out. The p-toluolsulfochlorid, p-toluolsulfoacid, hydrochloric, sulfuric, nitric acids, dioxide selenium and phthalic anhydride have been chosen as modifiers. For the first time quaternary ammonium salts, derivatives of N-oxide and N (2)-oxyharminiumphthalate harmine are synthesized. The structure of the synthesized compounds is determined by methods of the spectral analysis and X-ray analysis. Antimicrobic and phagocytosis stimulating activities of isolated alkaloids and their derivatives are investigated.

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Maruša, Mur, Kos Žiga, Ravnik Miha, and Muševič Igor. "Continuous generation of topological defects in a passively driven nematic liquid crystal." Nature Communications 13, no. 1 (2022): 6855. https://doi.org/10.1038/s41467-022-34384-5.

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Synthetic active matter is emerging as the prime route for the realisation of biological mechanisms such as locomotion, active mixing, and self-organisation in soft materials. In particular, passive nematic complex fluids are known to form out-of-equilibrium states with topological defects, but their locomotion, activation and experimental realization has been developed and understood to only a limited extent. Here, we report that the concentration-driven flow of small molecules triggers turbulent flow in the thin film of a nematic liquid crystal that continuously generates pairs of topological defects with an integer topological charge. The diffusion results in the formation of counter-rotating vortex rolls in the liquid crystal, which above a velocity threshold transform into a turbulent flow with continuous generation and annihilation of the defect pairs. The pairs of defects are created by the self-amplifying splay instability between the vortices, until a pair of oppositely charged defects is formed.

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Vakhin, Alexey V. "Rock Mineral Components’ Effects on Heavy and Shale Oil Transformation during Aquathermolysis." Energies 15, no. 16 (2022): 6047. http://dx.doi.org/10.3390/en15166047.

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One of the main topics that generate the interest of experts nowadays involves the processes of organic matter chemical transformation during heavy and shale oil reservoirs’ development via thermally enhanced oil recovery. It is common knowledge that the host rock has a catalytic effect on the ongoing processes. In addition, oil transformation is mostly associated with destructive processes of resins and asphaltenes molecules. As a result, this would provide an increase in oil mobility as a result of kerogen destruction in shale oil. This ensures the formation of synthetic oil and an increase in the filtration characteristics of the rock. Besides, iron-containing compounds in the composition of the rock are catalytically active in the above processes. Moreover, clay minerals have high catalytic activity for many reactions of organic matter transformation. This review considers publications that study the role played by the rock and its individual components in the processes of in situ upgrading of heavy and shale oil.

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Sim, San, Injun Hwang, Woosun Choi, and Yongseon Kim. "Synthesis and Surface Coating of LiMn2O4 Nanorods for the Cathode of the Lithium-Ion Battery." Journal of Nanoscience and Nanotechnology 21, no. 10 (2021): 5289–95. http://dx.doi.org/10.1166/jnn.2021.19364.

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MnO2 nanorods are prepared using a hydrothermal method, and used as precursors for the synthesis of LiMn2O4 nanorod-based active material for the cathode of lithium-ion batteries. The effects of additives, pressure, reactant concentration in the solution, and reaction time during the hydrothermal synthesis on the morphology of MnO2 are examined. For the synthesis of the LiMn2O4 nanorods, two synthetic methods, hydrothermal processing of the MnO2 precursor in a Li-containing solution, and the solid-state reaction of the precursor with LiOH·H2O powder are tested. The morphological and electrochemical properties of the resulting materials are then analyzed. The rate and cycle performances of the LiMn2O4 nanorods are considerably improved by a composite coating of Li-ion-conductive Li2O–2B2O3 and electrically conductive carbon. Because the conductive properties of these coating materials can be obtained with low crystallinity of them, superior coating performance is attainable with relatively low-temperature of after heating, which is advantageous in preserving the morphology of LiMn2O4 nanorods.

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Li, Jinfeng, and Xiaobing Zhang. "Active flow control for supersonic aircraft: A novel hybrid synthetic jet actuator." Sensors and Actuators A: Physical 302 (February 2020): 111770. http://dx.doi.org/10.1016/j.sna.2019.111770.

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Marchetti, Angela, Miriam Cerrillo Moreno, Roberto Lauri, and Marco Zeppilli. "Optimizing Hydrogen Production Through Efficient Organic Matter Oxidation Performed by Microbial Electrolysis Cells." Processes 13, no. 4 (2025): 1231. https://doi.org/10.3390/pr13041231.

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Microbial electrolysis cells (MECs) represent a pioneering technology for sustainable hydrogen production by leveraging bioelectrochemical processes. This study investigates the performance of a single-chamber cathodic MEC, where a cation exchange membrane separates the electrically active bioanode from the cathode. The system was constantly fed with a synthetic carbonaceous solution, employing a working potential of +0.3 V vs. SHE and an organic loading rate of 2 gCOD/Ld with a hydraulic retention time of 0.3 d. Notably, no methanogenic activity was detected, likely due to the establishment of an alkaline pH in the cathodic chamber. Under these conditions, the system exhibited good performance, achieving a current density of approximately 115 A/m3 and a hydrogen production rate of 1.28 m3/m3d. The corresponding energy consumption for hydrogen production resulted in 6.32 kWh/Nm3 H2, resulting in a slightly higher energetic cost compared to conventional electrolysis; moreover, an average energy efficiency of 85% was reached during the steady-state condition. These results demonstrate the potential of MECs as an effective and sustainable approach for biohydrogen production by helping the development of greener energy solutions.

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Archana, S., V. S. Devika, Prasanna More, Ravi Kumar Pujala, and Surajit Dhara. "Electrophoretic propulsion of matchstick-shaped magnetodielectric particles in the presence of external magnetic fields in a nematic liquid crystal." Soft Matter, 2024. http://dx.doi.org/10.1039/d3sm01382k.

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Synthesis of micro and nanoparticles of pre-designed shape and surface properties is an integral part of soft and synthetic active matter. We report synthesis of matchstick-shaped (MS) magnetodielectric particles and...

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Nasirimarekani, Vahid, Tobias Strübing, Andrej Vilfan, and Isabella Guido. "Tuning the Properties of Active Microtubule Networks by Depletion Forces." June 16, 2021. https://doi.org/10.1021/acs.langmuir.1c00426.

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Suspensions of microtubules and nonadsorbing particles form thick and long bundles due to depletion forces. Such interactions act at the nanometer scale and define the structural and dynamical properties of the resulting networks. In this study, we analyze the depletion forces exerted by two types of nonadsorbing particles, namely, the polymer, poly(ethylene glycol) (PEG), and the block copolymer, Pluronic. We characterize their effects both in passive and active networks by adding motor proteins to the suspensions. By exploiting its bundling effect via entropic forces, we observed that PEG generates a network with thick structures showing a nematic order and larger mesh size. On the other hand, Pluronic builds up a much denser gel-like network without a recognizable mesh structure. This difference is also reflected in the network activity. PEG networks show moderate contraction in lateral directions while Pluronic networks exhibit faster and isotropic contraction. Interestingly, by mixing the two nonadsorbing polymers in different ratios, we observed that the system showed a behavior that exhibited properties of both agents, leading to a robust and fast responsive structure compared to the single-depletant networks. In conclusion, we show how passive osmotic compression modifies the distribution of biopolymers. Its combination with active motors results in a new active material with potential for nanotechnological applications.

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Senoussi, Anis, Jean-Christophe Galas, and André Estevez-Torres. "Programmed mechano-chemical coupling in reaction-diffusion active matter." Science Advances 7, no. 51 (2021). http://dx.doi.org/10.1126/sciadv.abi9865.

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Grauer, Jens, Falko Schmidt, Jesús Pineda, et al. "Active droploids." Nature Communications 12, no. 1 (2021). http://dx.doi.org/10.1038/s41467-021-26319-3.

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AbstractActive matter comprises self-driven units, such as bacteria and synthetic microswimmers, that can spontaneously form complex patterns and assemble into functional microdevices. These processes are possible thanks to the out-of-equilibrium nature of active-matter systems, fueled by a one-way free-energy flow from the environment into the system. Here, we take the next step in the evolution of active matter by realizing a two-way coupling between active particles and their environment, where active particles act back on the environment giving rise to the formation of superstructures. In experiments and simulations we observe that, under light-illumination, colloidal particles and their near-critical environment create mutually-coupled co-evolving structures. These structures unify in the form of active superstructures featuring a droplet shape and a colloidal engine inducing self-propulsion. We call them active droploids—a portmanteau of droplet and colloids. Our results provide a pathway to create active superstructures through environmental feedback.

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Ziepke, Alexander, Ivan Maryshev, Igor S. Aranson, and Erwin Frey. "Multi-scale organization in communicating active matter." Nature Communications 13, no. 1 (2022). http://dx.doi.org/10.1038/s41467-022-34484-2.

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AbstractThe emergence of collective motion among interacting, self-propelled agents is a central paradigm in non-equilibrium physics. Examples of such active matter range from swimming bacteria and cytoskeletal motility assays to synthetic self-propelled colloids and swarming microrobots. Remarkably, the aggregation capabilities of many of these systems rely on a theme as fundamental as it is ubiquitous in nature: communication. Despite its eminent importance, the role of communication in the collective organization of active systems is not yet fully understood. Here we report on the multi-scale self-organization of interacting self-propelled agents that locally process information transmitted by chemical signals. We show that this communication capacity dramatically expands their ability to form complex structures, allowing them to self-organize through a series of collective dynamical states at multiple hierarchical levels. Our findings provide insights into the role of self-sustained signal processing for self-organization in biological systems and open routes to applications using chemically driven colloids or microrobots.

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Journal articles on the topic 'Synthetic Active Matter'

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