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Active particles under soft confinement such as droplets or vesicles present intriguing phenomena, as collective motion emerges alongside the deformation of the environment. A model is employed to systematically investigate droplet morphology and particle distribution in relation to activity and concentration,revealing that active particles have the capacity to induce enhanced shape fluctuations in the droplet interface with respect to the thermal fluctuations, aligning with recent experimental observations. A rich phase behaviour can be identified with two different mechanism of droplet breakage. [ABSTRACT FROM AUTHOR]

Biochemical communication is ubiquitous in life. Biology uses chemical reaction networks to regulate concentrations of myriad signaling molecules. Recent advances in supramolecular and systems chemistry demonstrate that feedback mechanisms of such networks can be rationally designed but strategies to transmit and process information encoded in molecules are still in their infancy. Here, we designed a polyelectrolyte reaction network maintained under out‐of‐equilibrium conditions using pH gradients in flow. The network comprises two weak polyelectrolytes (polyallylamine, PAH, and polyacrylic acid, PAA) in solution and one immobilized on the surface (poly‐l‐lysine, PLL). We chose PAH and PAA as their complexation process is known to be history‐dependent (i. e., the preceding state of the system can determine the next state). Surprisingly, we found that the hysteresis diminished as the PLL‐coated surface supported rather than perturbed the formation of the complex. PLL‐coated surfaces are further exploited to establish that reversible switching between the assembled and disassembled state of polyelectrolytes can process signals encoded in the frequency and duration of pH pulses. We envision that the strategy employed to modulate information in this polyelectrolyte reaction network could open novel routes to transmit and process molecular information in biologically relevant processes. [ABSTRACT FROM AUTHOR]

In supramolecular chemistry, photostimulants are generally combined with a static solution under thermodynamic equilibrium with no time progression. After reaching the thermodynamic state, self‐assembly events contain various species–a mixture of component molecules, intermediate species, and completed assemblies–which light reaches uniformly. In this study, snapshot control of supramolecular polymerization was first combined with pinpoint photoirradiation using a microflow system. Employing the azobenzene derivative trans‐C3NO as a monomer, a snapshot moment of supramolecular polymerization along a microflow channel was selectively irradiated with UV light at 365 nm in a space‐resolved manner, so that the monomers, intermediates (oligomers), or extended supramolecular polymers were selectively exposed to light stimuli. We found that a pinpoint photostimulus to each snapshot moment had a pronounced effect on the kinetic pathway by tuning the timing at which the snapshot moment of cis‐C3NO was generated. Upon irradiation in the upstream region, in the very early stages before initiating polymerization, supramolecular polymerization was suppressed by generating a less reactive cis‐C3NO monomer. However, photoirradiation does not affect the supramolecular polymers in the downstream region because of their stiff nature. Remarkably, when irradiating the middle stream region involving a soft‐natured intermediate species, supramolecular copolymerization occurred through in situ conversion from trans‐ and cis‐C3NO inside the primitive supramolecular polymer. Loose monomer stacking in the primitive aggregate endows it with mechanoresponsiveness. Under the influence of shear force in a Hagen–Poiseuille flow, the resultant supramolecular copolymers containing geometrically different cis‐isomers were rolled up and transformed into a micrometer‐sized disk‐like structure. During the in situ supramolecular copolymerization and transformation to the disk structure, a liquid–liquid interface generated in the laminar flow acted as a template to fix the orientation of the monomers and supramolecular polymers, leading to the uniform disk formation. Furthermore, monomers' orientation in the aligned supramolecular polymers are fixed on the interface, on which light is always irradiated in an anisotropic manner. This results in both complexity at the molecular level and long‐range structural order such as regular rolling up at the micrometer range over the molecular scale. By incorporating the photostimulus system, microflow extends its potential for supramolecular chemistry. [ABSTRACT FROM AUTHOR]

We study by femtosecond infrared spectroscopy the ultrafast and persistent photoinduced phase transition of the Rb0.94Mn0.94Co0.06[Fe(CN)6]0.98 ⋅ 0.2H2O material, induced at room temperature by a single laser shot. This system exhibits a charge‐transfer based phase transition with a 75 K wide thermal hysteresis, centred at room temperature, from the low temperature Mn3+−N−C−Fe2+ tetragonal phase to the high temperature Mn2+−N−C−Fe3+ cubic phase. At room temperature, the photoinduced phase transition is persistent. However, the out‐of‐equilibrium dynamics leading to this phase is multi‐scale. Femtosecond infrared spectroscopy, particularly sensitive to local reorganizations through the evolution of the frequency of the N−C vibration modes with the different characteristic electronic states, reveals that at low laser fluence and on short time scale, the photoexcitation of the Mn3+−N−C−Fe2+ phase creates small charge‐transfer polarons [Mn2+−N−C−Fe3+]* within ≃250 fs. The local trapping of photoinduced intermetallic charge‐transfer is characterized by the appearance of a polaronic infrared band, due to the surrounding Mn2+−N−C−Fe2+ species. Above a threshold fluence, when a critical fraction of small CT‐polarons is reached, the macroscopic phase transition to the persistent Mn2+−N−C−Fe3+ cubic phase occurs within ≃ 100 ps. This non‐linear photo‐response results from elastic cooperativity, intrinsic to a switchable lattice and reminiscent of a feedback mechanism. [ABSTRACT FROM AUTHOR]

Chemically fueled chemical reaction networks (CRNs) are essential in controlling dissipative self‐assembly. A key challenge in the field is to store chemical fuel‐precursors or "pre‐fuels" in the system that are converted into activating or deactivating fuels in a catalytically controlled CRN. In addition, real‐time control over catalysis in a CRN by light is highly desirable, but so far not yet achieved. Here we show a catalytically driven CRN that is photoinitiated with 450 nm light, producing activated monomers that go on to perform transient self‐assembly. Monomer activation proceeds via photoredox catalysis, converting the monomer alcohol groups into the corresponding aldehydes that self‐assemble into large supramolecular fibers. Monomer deactivation is achieved by organometallic catalysis that relies on pre‐fuel hydrolysis to release formate (i.e. the deactivating fuel). Additionally, irradiation with 305 nm light accelerates the release of formate by photo‐uncaging the pre‐fuel, leading to a factor of ca. 2 faster deactivation of the monomer. Overall, we show transient self‐assembly upon visible light photoactivation, and tunable life‐times by ultraviolet light. [ABSTRACT FROM AUTHOR]

A well‐behaved dynamic library composed of two imines and corresponding amines was subjected to the action of an activated carboxylic acid (ACA), whose decarboxylation is known to be base promoted, in different solvents, namely CD2Cl2, CD3CN, and mixtures of them. Two non‐equilibrium systems are consequently obtained: i) a dissipative (CD2Cl2) and ii) an out‐of‐equilibrium (CD3CN) dynamic library whose composition goes back to equilibrium after a given time. In the former case, the library is fully coupled with the decarboxylation of the ACA, while in the latter, an energy ratchet operates. In the mixed solvents, the library exhibits a mediated behavior. Interestingly, in the presence of an excess of added ACA, the different behavior of the imine library in the two solvents is expected to manifest only when the excess acid is consumed. [ABSTRACT FROM AUTHOR]

We investigate resonant third-harmonic generation in near-zero index thin films driven out-of-equilibrium by intense optical excitation. Adopting the Landau weak coupling formalism to incorporate electron–electron and electron–phonon scattering processes, we derive a novel set of hydrodynamic equations accounting for collision-driven nonlinear dynamics in sodium. By perturbatively solving hydrodynamic equations, we model third-harmonic generation by a thin sodium film, finding that such a nonlinear process is resonant at the near-zero index resonance of the third-harmonic signal. Thanks to the reduced absorption of sodium, we observe that third-harmonic resonance can be tuned by the impinging pump radiation angle, efficiently modulating the third-harmonic generation process. Furthermore, owing to the metallic sodium response at the pump optical wavelength, we find that the third-harmonic conversion efficiency is maximised at a peculiar thin film thickness where evanescent back-reflection provides increased field intensity within the thin film. Our results are relevant for the development of future ultraviolet light sources, with potential impact for innovative integrated spectroscopy schemes. [ABSTRACT FROM AUTHOR]

This document provides a list of references to scientific articles and documents that explore various aspects of epoxy thermoset resins. The articles cover topics such as the curing behavior of thermosets, the dynamics of nanoparticles within polymer melts, the nanostructural heterogeneity of epoxy networks, and the effects of temperature on the fracture properties of epoxy systems. The articles utilize techniques such as X-ray photon correlation spectroscopy and molecular dynamics simulations to investigate the behavior and properties of epoxy resins. These resources offer valuable insights for researchers studying epoxy materials. [Extracted from the article]

The use of Activated Carboxylic Acids (ACAs) allows the time‐controlled operation of dissipative chemical systems based on the acid‐base reaction by providing both the stimulus that temporarily drives a physicochemical change and, subsequently, the counter‐stimulus with a single reagent addition. However, their application is inherently limited to acid‐sensitive systems. To overcome this limitation, we herein develop a straightforward device for the transduction of the acid‐base stimuli delivered by an ACA into a voltage signal that, in turn, is used to control voltage‐sensitive circuits that are not pH‐responsive by themselves. The signal transductor can be easily assembled from common laboratory equipment and employs aqueous solutions of readily available chemicals. Furthermore, the operator can simply and intuitively tune the amplitude of the voltage signal, as well as its duration and offset by varying the concentration of the chemical species involved in the transduction process. [ABSTRACT FROM AUTHOR]

The structure and dynamics of polystyrene (PS)‐b‐poly(ethylene oxide) block copolymers (BCPs) are studied. The BCPs exhibit microphase‐separated cylindrical and lamellar morphologies. Structural dynamics are measured with X‐ray photon correlation spectroscopy in the small‐angle regime. Morphologies and domain sizes are evaluated using small‐angle X‐ray scattering (SAXS), scanning electron microscopy, and atomic force microscopy. Different solvent processing conditions are investigated. Grain sizes evaluated using SAXS are found to depend on processing only for the rubbery majority BCP. The structural relaxation times are examined as a function of PS volume fraction, temperature, morphology, and structural sizes. Well above the glass transition temperature (Tg) of PS, all samples exhibit stretched autocorrelation decays and diffusive dynamics. Near Tg of PS, the dynamics of all samples are anomalous with compressed autocorrelation decays and hyperdiffusive dynamics. This transition occurs at 153 °C or 1.13 Tg of PS. In the diffusive regime (at high temperature), structural relaxation times are dependent on the processing method. Near PS Tg (at low temperature), structural relaxation times scale with the PS volume fraction. Structural relaxation times do not correlate with grain size, indicating that the out‐of‐equilibrium state of PS dominates the structural dynamics of these strongly phase‐segregated BCPs. [ABSTRACT FROM AUTHOR]

Introduction: Cross-linkable polymers are in widespread use in a variety of industries because of their thermomechanical toughness, chemical resistance, and adhesive strength. But traditional methods to characterize these materials are insufficient for fully capturing the complex chemical and physical mechanisms of the crosslinking reaction. In this study, in situ X-ray photon correlation spectroscopy (XPCS) was used to investigate the crosslinking kinetics of a two-component epoxy resin adhesive.Materials and methods: With XPCS, we tracked the temporally resolved dynamics of silica filler particles, which served as probes of the internal dynamics of the thermoset network and allowed us to study the crosslinking process. The epoxy was cured isothermally at 40 °C and 80 °C to study the effects of curing temperature on the epoxy’s crosslinking reaction. XPCS results were compared to dielectric analysis (DEA) results, to demonstrate the similarities between a traditional technique and XPCS, and highlight the additional information gained with XPCS.Results and discussion: The epoxy resin was found to be highly sensitive to temperature. The epoxy samples exhibited different relaxation processes depending on isothermal cure temperature, indicating a complex relationship between applied temperature and the development of stress/relaxation conditions associated with formation of the thermoset network. Heating to the isothermal temperature setpoint at the start of curing promoted gelation, but the vitrification process was not completed during the isothermal curing stage. Instead, cooling the sample to room temperature facilitated the final vitrification process. This paper contextualizes this epoxy’s results within the broader field of thermoset study via XPCS, and advocates for XPCS as a fundamental technique for the study of complex polymers.

Artificial cell and organelle construction has recently gained substantial attention to generate simplified models for understanding of biological phenomena, or micro‐ and nanomachines for biomedical and biotechnological applications. A wide array of building blocks has been employed to build these systems as membraneless structures with the ability to compartmentalize chemical reactions by enhanced partitioning, or as membrane‐defined entities that provide a physical barrier that inhibits the interference of external factors. While these systems present unique properties that enable high fidelity to biological processes, they present limited ability to recreate the high selectivity and specificity of small molecule trafficking observed in biological membranes. Owing to their high chemical versatility, polymers can be leveraged to generate 3D structures that resemble biological membranes while providing transmembrane chemical motifs that enable responsiveness to a wide array of stimuli. This Concept Article discusses the ability to control membrane transport facilitating the emergence of out‐of‐equilibrium feedback mechanisms that ultimately modulate enzymatic rates. This can be employed to engineer future artificial cells and organelles that display homeostasis as a mechanism of self‐adaptation to continuously evolving environments. [ABSTRACT FROM AUTHOR]

Hierarchical DNA nanostructures offer programmable functions at scale, but making these structures dynamic, while keeping individual components intact, is challenging. Here we show that the DNA A‐motif—protonated, self‐complementary poly(adenine) sequences—can propagate DNA origami into one‐dimensional, micron‐length fibrils. When coupled to a small molecule pH regulator, visible light can activate the hierarchical assembly of our DNA origami into dissipative fibrils. This system is recyclable and does not require DNA modification. By employing a modular and waste‐free strategy to assemble and disassemble hierarchical structures built from DNA origami, we offer a facile and accessible route to developing well‐defined, dynamic, and large DNA assemblies with temporal control. As a general tool, we envision that coupling the A‐motif to cycles of dissipative protonation will allow the transient construction of diverse DNA nanostructures, finding broad applications in dynamic and non‐equilibrium nanotechnology. [ABSTRACT FROM AUTHOR]

Inspired from dynamic living systems that operate under out‐of‐equilibrium conditions in biology, developing supramolecular hydrogels with self‐regulating and autonomously dynamic properties to further advance adaptive hydrogels with life‐like behavior is important. This review presents recent progress of bio‐inspired supramolecular hydrogels out‐of‐equilibrium. The principle of out‐of‐equilibrium self‐assembly for creating bio‐inspired hydrogels is discussed. Various design strategies have been identified, such as chemical‐driven reaction cycles with feedback control and physically oscillatory systems. These strategies can be coupled with hydrogels to achieve temporal and spatial control over structural and mechanical properties as well as programmable lifetime. These studies open up huge opportunities for potential applications, such as fluidic guidance, information storage, drug delivery, actuators and more. Finally, we address the challenges ahead of us in the coming years, and future possibilities and prospects are identified. [ABSTRACT FROM AUTHOR]

The paper discusses the implications of disaggregation within the post-Keynesian debate on the long-run convergence of the degree of capacity utilization toward the normal one. The debate is related to the emergence of Harrodian instability inside multiplier–accelerator models and has been characterized by two "opposite" positions: the supermultiplier (SM) and the neo-Kaleckian approaches. These approaches solve the instability issue differently, but both share the postulate that an equilibrium position is such only if the desired state of firms is realized. In the long run, the economy converges toward a fully adjusted position where the realized degree of capacity utilization is equal to the normal/desired one. In this paper, we develop an Agent Based—Stock Flow Consistent version of the SM model showing that once multiplier–accelerator mechanisms are explicitly reproduced in a multi-firm economy, the accumulation process can be stable without requiring any convergence between the actual and normal rate. Conversely, the modeled economy displays two emergent properties: the fluctuations of the business cycle arise endogenously, and the long-run aggregate degree of capacity utilization persistently fluctuates around a level lower than the normal one. To this extent, the quasi-steady state corresponds to a situation where the desired state of agents is not realized and single elements are not in equilibrium, but the aggregate is. Finally, we compare outcomes produced from the model according to different scenarios on firms' heterogeneity and network symmetries. [ABSTRACT FROM AUTHOR]

Relaying conformational change over several nanometers is central to the function of allosterically regulated proteins. Replicating this mechanism artificially would provide important communication tools, but requires nanometer‐sized molecules that reversibly switch between defined shapes in response to signaling molecules. In this work, 1.8 nm long rigid rod oligo(phenylene‐ethynylene)s are scaffolds for switchable multi‐squaramide hydrogen‐bond relays. Each relay can adopt either a parallel or an antiparallel orientation relative to the scaffold; the preferred orientation is dictated by a director group at one end. An amine director responded to proton signals, with acid‐base cycles producing multiple reversible changes in relay orientation that were reported by a terminal NH, which is 1.8 nm distant. Moreover, a chemical fuel acted as a dissipative signal. As the fuel was consumed, the relay reverted to its original orientation, illustrating how information from out‐of‐equilibrium molecular signals can be communicated to a distant site. [ABSTRACT FROM AUTHOR]

The operation of a dissipative network composed of two or three different crown‐ether receptors and an alkali metal cation can be temporally driven by the use (combined or not) of two orthogonal stimuli of a different nature. More specifically, irradiation with light at a proper wavelength and/or addition of an activated carboxylic acid, are used to modulate the binding capability of the above crown‐ethers towards the metal ion, allowing to control over time the occupancy of the metal cation in the crown‐ether moiety of a given ligand. Thus, application of either or both of the stimuli to an initially equilibrated system, where the metal cation is distributed among the crown‐ether receptors depending on the different affinities, causes a programmable change in the receptor occupancies. Consequently, the system is induced to evolve to one or more out‐of‐equilibrium states with different distributions of the metal cation among the different receptors. When the fuel is exhausted or/and the irradiation interrupted, the system reversibly and autonomously goes back to the initial equilibrium state. Such results may contribute to the achievement of new dissipative systems that, taking advantage of multiple and orthogonal stimuli, are featured with more sophisticated operating mechanisms and time programmability. [ABSTRACT FROM AUTHOR]

Protein turnover (PT) has been formally defined only in equilibrium conditions, which is ill‐suited to quantify PT during dynamic processes that occur during embryogenesis or (extra) cellular signaling. In this Hypothesis, we propose a definition of PT in an out‐of‐equilibrium regime that allows the quantification of PT in virtually any biological context. We propose a simple mathematical and conceptual framework applicable to a broad range of available data, such as RNA sequencing coupled with pulsed‐SILAC datasets. We apply our framework to a published dataset and show that stimulation of mouse dendritic cells with LPS leads to a proteome‐wide change in PT. This is the first quantification of PT out‐of‐equilibrium, paving the way for the analysis of biological systems in other contexts. [ABSTRACT FROM AUTHOR]

Nature‐inspired synthetic dissipative self‐assemblies have attracted much attention recently. However, it remains a major challenge to achieve precise control over dissipative supramolecular assembly structures and functions of self‐contained systems. Here we combine light and electricity as two clean, and spatiotemporally addressable fuels to provide precise control over the morphology for dissipative self‐assembly of a perylene bisimide glycine (PBIg) building block in a self‐contained solution. In this design, electrochemical oxidation provides the positive fuel to activate PBIg self‐assembly while photoreduction supplies the negative fuel to deactivate the system for disassembly. Through programming the two counteracting fuels, we demonstrated the control of PBIg self‐assembly into a variety of assembly morphologies in a self‐contained system. In addition, by exerting light and electrical dual fuels simultaneously, we could create an active homeostasis exhibiting dynamic instability, leading to morphological change to asymmetric assemblies with curvatures. Such precise control over self‐assembly of self‐contained systems may find future applications in programming complex active materials as well as formulating pharmaceutical reagents with desired morphologies. [ABSTRACT FROM AUTHOR]

This work reports a basic microflow system capable of performing multistep supramolecular polymerization. In this system, injection of the monomer, directional supramolecular copolymerization, removal of the unreacted monomer, and purification of the product supramolecular diblock copolymers are realized along a three‐stream flow. When injecting a supramolecular polymer into the central stream of the three‐stream flow, the supramolecular polymerization always occurs in the central flow, with the two lateral flows serving as supply and removal lines for the monomer. Employing two kinds of perylene bisimide derivatives as monomers, we confirmed that the reaction occurred selectively at the forward‐facing terminus of the supramolecular polymer, along with recovery of the unreacted monomer, ultimately leading to a high‐purity supramolecular diblock copolymer. Diblock copolymers are basic units for preparing multicomponent supramolecular block copolymers. Thus, connecting the present system in series would, in principle, result in a "microplant" capable of producing supramolecular polymers having desired inner complexity. [ABSTRACT FROM AUTHOR]

Among non-coding RNAs, microRNAs are pivotal post-transcriptional regulators of gene expression in higher eukaryotes. Through a titration-based mechanism of interaction with their target RNAs, microRNAs can mediate a weak but pervasive form of RNA cross-regulation, as different endogenous RNAs can be effectively coupled by competing for microRNA binding (a phenomenon now known as "crosstalk"). Mathematical modeling has been proven of great help in unraveling many features of these competing endogenous RNA (ceRNA) interactions. However, although many studies have been devoted to the steady-state properties of this indirect regulatory layer, little is known about how the information encoded in frequency, amplitude, duration, and other features of regulatory signals can affect the resulting ceRNA crosstalk picture and hence the overall patterns of gene expression. Here, we focus on such dynamical aspects, with a special emphasis on the encoding and decoding of time-dependent signals., (© 2025. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Matter is dynamic and changes under the effect of various external constraints, in particular light. The development of ultra-fast techniques now makes it possible to study the elementary mechanisms of ultrafast photoinduced phenomena, in particular by following the dynamics of electronic and structural degrees of freedom of matter. These studies provide a better understanding of these non-equilibrium processes in order to control the physical properties of molecules and materials by light. In this introductory article we discuss different aspects of studying ultra-fast condensed matter phenomena.

In this work, we demonstrate pH sensing using the out-of-equilibrium body potential (V B) monitored in silicon-on-insulator (SOI) double-gate "ISFET-like" devices with deposited metal contacts. Similar to the behavior of a dual-gate ISFET, in this study, the conductive channel induced by the back-gate voltage at the silicon/buried oxide (Si/BOX) interface is modulated by the charges to-be-sensed that are intentionally placed on the top silicon oxide layer SiO 2 covering the Si film. The detection of the surface charge modulation was evidenced by monitoring in real-time the out-of-equilibrium body potential, while the classic shift in the drain current served as control experiment and for benchmarking. These first experiments demonstrate the successful implementation of this new pH detection paradigm, with super-Nernstian sensitivity. To provide optimization options for the body-potential sensing, TCAD simulations of the pH sensors were performed in a 2D structure and illustrated the possibility to further enhance the device sensitivity with an optimized architecture. Moreover, the pH-induced shift occurs at very high applied gate biases for the drain current, contrary to the body potential, which implies a sensor with lower power consumption when V B is used as reading method. Thus, body potential monitoring provides a promising reading method to reach the required low-power consumption regime of the tomorrow's sensing devices. [Display omitted] • Out-of-equilibrium body potential, a new dynamic reading method with ISFET-like devices. • Super-Nernstian response in Silicon-On-Insulator sensors with deposited metal contacts. • Fabrication of ISFETs for "in-liquid" detection based on the out-of-equilibrium body potential. • Sensitivity investigation of ISFET sensors through TCAD simulations. • Benchmark of sensing: out-of-equilibrium body potential versus drain current method. [ABSTRACT FROM AUTHOR]

It is common to compare life with machines. Both consume fuel and release waste to run. In biology, the engine that drives the living system is referred to as metabolism. However, attempts at deciphering the origins of metabolism do not focus on this energetic relationship that sustains life but rather concentrate on nonenzymatic reactions that produce all the intermediates of an extant metabolic pathway. Such an approach is akin to studying the molecules produced from the burning of coal instead of deciphering how the released energy drives the movement of pistons and ultimately the train when investigating the mechanisms behind locomotion. Theories that do explicitly invoke geological chemical gradients to drive metabolism most frequently feature hydrothermal vent conditions, but hydrothermal vents are not the only regions of the early Earth that could have provided the fuel necessary to sustain the Earth's first (proto)cells. Here, we give examples of prior reports on protometabolism and highlight how more recent investigations of out-of-equilibrium systems may point to alternative scenarios more consistent with the majority of prebiotic chemistry data accumulated thus far. This article is part of the theme issue 'Emergent phenomena in complex physical and socio-technical systems: from cells to societies'. [ABSTRACT FROM AUTHOR]

Among the key characteristics of living systems are their ability to self‐replicate and the fact that they exist in an open system away from equilibrium. Herein, we show how the outcome of the competition between two self‐replicators, differing in size and building block composition, is different depending on whether the experiments are conducted in a closed vial or in an open and out‐of‐equilibrium replication–destruction regime. In the closed system, the slower replicator eventually prevails over the faster competitor. In a replication‐destruction regime, implemented through a flow system, the outcome of the competition is reversed and the faster replicator dominates. The interpretation of the experimental observations is supported by a mass‐action‐kinetics model. These results represent one of the few experimental manifestations of selection among competing self‐replicators based on dynamic kinetic stability and pave the way towards Darwinian evolution of abiotic systems. [ABSTRACT FROM AUTHOR]

[Display omitted] In living systems, dynamic processes like dissipative assembly, polymorph formation, and destabilization of hydrophobic domains play an indispensable role in the biochemical processes. Adaptation of biological self-assembly processes to an amphiphilic molecule leads to the fabrication of intelligent biomaterials with life-like behavior. An amphiphilic glycolipid molecule was engineered into various dissipative assemblies (vesicles and supramolecular nanotube-composed hydrogels) by using two activation steps, including heating-cooling and shear force in method-1 or boric acid/glycolipid complexation and shear force in method-2. The influence of number of activation steps on vesicle to nanotube phase transitions and activation method on the properties of hydrogels were investigated, where the morphological transformations and destabilization of hydrophobic domains resulted from a bilayer to a higher-order crystal structure. Hydrophobic and hydrophilic cargos encapsulated in the dissipative assemblies (vesicles and injectable hydrogels) can be released in a controlled manner via changing the activation method. The reported adaptive materials engineered by dual activation steps are promising self-assembled systems for programmed release of loaded cargos at a tunable rate. [ABSTRACT FROM AUTHOR]

A molecular switch based on the metastable radical anion derived from a substituted heteroaryl quinone is described. Pyrrolyl quinone thiocyanate (PQ 9) showed an interaction with the fluoride anion that was visible to the naked eye and quantified by UV/vis and 1H and 13 C NMR. The metastable quinoid species formed by the interaction with F - ("ON" state) showed a molecular switching effect autocontrolled by the presence of ascorbate ("OFF" state) and back to the "ON" state by an autooxidation process, measured by visible and UV/vis spectroscopy. Due to its out-of-equilibrium properties and the exchange of matter and energy, a dissipative structural behaviour is proposed. Considering its similarity to the mechanism of coenzyme Q in oxidative phosphophorylation, PQ 9 was evaluated on Saccharomyces cerevisiae mitochondrial function for inhibition of complexes II, III and IV, reactive oxygen species (ROS) production, catalase activity and lipid peroxidation. The results showed that PQ 9 inhibited complex III activity as well as the activity of all electron transport chain (ETC) complexes. In addition, PQ 9 reduced ROS production and catalase activity in yeast. The results suggest that PQ 9 may have potential applications as a new microbicidal compound by inducing ETC dysfunction., (© 2024 Wiley-VCH GmbH.)

• A two-fluid model for water-incondensable gases and including heat and mass transfer is proposed. • Out-of-equilibrium source terms are modeled in a non-classical form considering two-fluid models. • The pressure relaxation effect is discretized using a new scheme. • Influence of the different relaxation effects is examined thanks to experimental results of a blowdown. Two phase flows including liquid water, vapor and non-condensable gases are often encountered in industrial applications. In this paper, an extension of the classical Baer-Nunziato two-fluid model is presented in order to account for the non-condensable gases. In this model, the vapor and non-condensable gases form a miscible mixture of gases at temperature equilibrium and kinematic equilibrium. The complete model then allows to account for the full kinematic and thermodynamic disequilibrium between the liquid phase and the gas phase. Moreover, a new form for the mass-transfer source-term has been retained. It leads to a more straightforward numerical integration. When focusing on the numerical scheme, a new algorithm is proposed here for the pressure relaxation effect. At last, some numerical experiments are performed in order to assess the behavior of the model with respect to the relaxation time-scales. [ABSTRACT FROM AUTHOR]

Abstract A rich variety of smart materials developed via supramolecular assembly strategies have been introduced in the past decades. However, most materials reside in the thermodynamic equilibrium state, opposed to those nonequilibrium structures with sophisticated functions that are observed in living systems. To develop advanced synthetic systems, chemists have begun to focus on how to use strategies similar to those used in biological systems for fabricating artificial out‐of‐equilibrium systems. Heretofore, a rich variety of artificial out‐of‐equilibrium systems have been developed. In this review, we have summarized the recent progress of artificial out‐of‐equilibrium systems and categorized them in terms of the chemical fuel used, including adenosine triphosphate (ATP), acid/base, carbodiimide reagents, and many others. For these self‐assembling systems, their design strategies, potential applications, as well as advantageous features have been discussed. At the end of this review, the remaining challenges and an outlook of the chemical‐fuel‐driven out‐of‐equilibrium systems were also discussed. It is believed that this review has provided some insights and could be useful for those who are interested in the out‐of‐equilibrium supramolecular assembling systems and their subsequent constructing strategies for various transient materials.

Herein we report transient out‐of‐equilibrium self‐assembly of molecules operated by gaseous fuel mixtures. The combination of an active gaseous chemical fuel and an inert gas or compressed air, which assists the degassing of the gaseous fuel from the solution, drives the transient self‐assembly process. The gaseous nature of the fuel as well as the exhaust helps in their easy removal and thereby prevents their accumulation within the system and helps in maintaining the efficiency of the transient self‐assembly process. The strategy is executed with a rather simple experimental set up and operates at ambient temperatures. Our approach may find use in the development of smart materials suitable for applications such as temporally active gas sensing and sequestration. [ABSTRACT FROM AUTHOR]

In this paper, we applied the out-of-equilibrium body potential measurements in a silicon-on-insulator (SOI) structure as a mean of DNA detection. The biochips were manufactured by 3-glycidoxypropyltrimethoxysilane (GOPTMS) functionalization, and single stranded DNA probes corresponding to human papillomavirus (HPV) were grafted onto the surface. The physicochemical characteristics were assessed by contact angle, Fourier Transform Infrared Spectrometry (FTIR) and microarray technique. The effects of the bio-chemical attachments to the surface of SOI were evaluated by body potential measurements implemented in the $\Psi $ -MOSFET configuration, typically used for electrical characterization of substrates. Body potential measurements versus the back gate voltage were able to distinguish the shift induced by DNA molecules only and the signatures were related to target DNA concentrations. The proposed reading method is remarkable owing to the fact that (1) it measures a potential (in the order of 1V) instead of a low current, (2) it allows fast sweeping measurements and (3) it requires a gate voltage close to 0V which induces less stress on the molecules attached to the surface. [ABSTRACT FROM AUTHOR]

This article focuses on one of the floating body effects in silicon-on-insulator (SOI) substrates, the out-of-equilibrium body potential. Unlike the already existing studies which explore either SOI fully fabricated devices or SOI wafers measured with pressure probes, here the out-of-equilibrium body potential is explored in SOI substrates with deposited metal contacts. Chromium and gold/titanium contacts of various geometries were deposited on silicon films of SOI and the floating body potential was examined in each case. The effect of annealing on the device behavior was also investigated. The performance of the deposited metal contacts is evaluated through current and potential monitoring under quasi-static conditions. Depending on the workfunction difference between metal and silicon film, the current measurements show that the contact behavior is mainly ohmic-like or Schottky-like. While body potential manifests itself with Schottky-like contacts, it does not seem to exhibit a significant response with ohmic contacts. The influence of the contact architecture on the body potential signature is illustrated, enabling the selection of the proper contact layout for an enhanced body potential response. [ABSTRACT FROM AUTHOR]

To understand how membrane‐free subcompartmentalization can modulate biochemical reactions by coupled spatial enzyme localization with substrate and product partitioning, we use microfluidic strategies to synthesize, stabilize and characterize micron‐sized functional coacervates in water−oil emulsions. Our methodologies have allowed for the first time to quantitatively characterize partition coefficients of a broad range of different molecules with different coacervate chemistries and to measure reaction rates of individual subcompartments and their surrounding aqueous environment at the single coacervate level. Our results show that sub‐compartmentalisation increases the overall rates of reactions. This bottom‐up synthetic strategy for the production of synthetic organelles offers a physical model for membrane‐free compartmentalization in biology and provides insights into the role of sub‐compartmentalisation in regulating out‐of‐equilibrium behaviours in biological systems. [ABSTRACT FROM AUTHOR]

A new discipline of “systems chemistry” is emerging, which aims to capture the complexity observed in natural systems within a synthetic chemical framework. Living systems rely on complex networks of chemical reactions to control the concentration of molecules in space and time. Despite the enormous complexity in biological networks, it is possible to identify network motifs that lead to functional outputs such as bistability or oscillations. To truly understand how living systems function, we need a complete understanding of how chemical reaction networks (CRNs) create function. We propose the development of a bottom-up approach to design and construct CRNs where we can follow the influence of single chemical entities on the properties of the network as a whole. Ultimately, this approach should allow us to not only understand such complex networks but also to guide and control their behavior.

Quantum turbulence deals with the phenomenon of turbulence in quantum fluids, such as superfluid helium and trapped Bose-Einstein condensates (BECs). Although much progress has been made in understanding quantum turbulence, several fundamental questions remain to be answered. In this work, we investigated the entropy of a trapped BEC in several regimes, including equilibrium, small excitations, the onset of turbulence, and a turbulent state. We considered the time evolution when the system is perturbed and let to evolve after the external excitation is turned off. We derived an expression for the entropy consistent with the accessible experimental data, which is, using the assumption that the momentum distribution is well-known. We related the excitation amplitude to different stages of the perturbed system, and we found distinct features of the entropy in each of them. In particular, we observed a sudden increase in the entropy following the establishment of a particle cascade. We argue that entropy and related quantities can be used to investigate and characterize quantum turbulence.

The helical stereomutation in the kinetically controlled coassembly of the reported carbonyl‐bridged triarylamines (CBTs) is described. The copolymerization of chiral CBTs (S)‐1 or (R)‐1 with achiral 2 in sergeants‐and‐soldiers (SaS) experiments results in a tunable helicity conditioned by the percentage of the chiral sergeant and by the cooling rate. The dissimilar inherent chirality of the extended monomeric (M) and intramolecularly H‐bonded metastable (M*) species, as well as the different stability of the kinetic trap of the chiral CBTs (S)‐1/(R)‐1 and the achiral CBT 2, condition the chirality transfer and afford J‐aggregates of inverse handedness. Stereomutation: The copolymerization of chiral CBTs (S)‐1 or (R)‐1 with achiral 2 results in a tunable helicity conditioned by the percentage of the chiral sergeant and by the cooling rate. The dissimilar chirality of the monomeric (M) and metastable (M*) species, and the different stability of the kinetic trap between (S)‐1/(R)‐1 and 2, condition the chirality transfer and afford J‐aggregates of inverse handedness. [ABSTRACT FROM AUTHOR]

Accurate control of the shape transformation of polymersome is an important and interesting challenge that spans across disciplines such as nanomedicine and nanomachine. Here, we report a fast and facile methodology of shape manipulation of polymersome via out-of-equilibrium polymer self-assembly and shape change by chemical addition of additives. Due to its increased permeability, hydrophilicity, and fusogenic properties, poly(ethylene oxide) was selected as the additive for bringing the system out of equilibrium via fast addition into the polymersome organic solution. A new shape, stomatocyte-in-stomatocyte (sto-in-sto), is obtained for the first time. Moreover, fast shape transformation within less than 1 min to other relevant shapes such as stomatocyte and large compound vesicles was also obtained and accurately controlled in a uniform dispersion. This methodology is demonstrated as a general strategy with which to push the assembly further out of equilibrium to generate unusual nanostructures in a controllable and fast manner. [ABSTRACT FROM AUTHOR]

Cellular networks are intrinsically subject to stochastic fluctuations, but analysis of the resulting noise remained largely limited to gene expression. The pathway controlling chemotaxis of Escherichia coli provides one example where posttranslational signaling noise has been deduced from cellular behavior. This noise was proposed to result from stochasticity in chemoreceptor methylation, and it is believed to enhance environment exploration by bacteria. Here we combined single-cell FRET measurements with analysis based on the fluctuation-dissipation theorem (FDT) to characterize origins of activity fluctuations within the chemotaxis pathway. We observed surprisingly large methylation-independent thermal fluctuations of receptor activity, which contribute to noise comparably to the energy-consuming methylation dynamics. Interactions between clustered receptors involved in amplification of chemotactic signals are also necessary to produce the observed large activity fluctuations. Our work thus shows that the high response sensitivity of this cellular pathway also increases its susceptibility to noise, from thermal and out-of-equilibrium processes.

The selection of polymorphs of the organic compound 5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile, ROY, is studied experimentally in the confined space between two horizontal glass plates when an acetone solution of ROY of variable concentration is injected at a variable flow rate into water. Depending on the local concentration within the radial flow, a polymorph selection is observed such that red prisms are favored close to the injection center while yellow needles are the preferred polymorph close to the edge of the injected ROY domain. At larger flow rates, a buoyancy-driven instability induces stripes at the outer edge of the displacement pattern, in which specific polymorphs are seen to crystallize. Our results evidence the possibility of a selection of ROY polymorph structures in out-of-equilibrium flow conditions.

Abstract: Our understanding of animal communication has been largely driven by advances in theory since empirical evidence has been difficult to obtain. Costly signaling theory became the dominant paradigm explaining the evolution of honest signals, according to which communication reliability relies on differential costs imposed on signalers to distinguish animals of different quality. On the other hand, mathematical models disagree on the source of costs at the communication equilibrium. Here, we present an empirical framework to study the evolution of honest signals that generates predictions on the form, function, and sources of reliability of visual signals. We test these predictions on the facial color patterns of the cooperatively breeding Princess of Burundi cichlid, Neolamprologus brichardi. Using theoretical visual models and behavioral experiments we show that these patterns possess stable chromatic properties for efficient transmission in the aquatic environment, while dynamic changes in signal luminance are used by the fish to communicate switches in aggressive intent. By manipulating signal into out‐of‐equilibrium expression and simulating a cheater invasion, we demonstrate that social costs (receiver retaliation) promote the honesty of this dynamic conventional signal. By directly probing the sender of a signal in real time, social selection is likely to be the mechanism of choice shaping the evolution of inexpensive, yet reliable context‐dependent social signals in general. [ABSTRACT FROM AUTHOR]