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Photoactive colloidal motors whose motion can be controlled and even programed via external magnetic fields have significant potential in practical applications extending from biomedical fields to environmental remediation. Herein, we report a “three in one” strategy in a Co/Zn-TPM (3-trimethoxysilyl propyl methacrylate) bimetallic Janus colloidal micromotor (BMT-micromotor) which can be controlled by an optical field, chemical fuel, and magnetic field. The speed of the micromotors can be tuned by light intensity and with the concentration of the chemical fuel of H2O2, while it could be steered and programed through magnetic field due to the presence of Co in the bimetallic part. Finally, the BMT-micromotors were employed to effectively remove rubidium metal ions and organic dyes (methylene blue and rhodamine b). Benefited of excellent mobility, multiple active sites, and hierarchical morphology, the micromotors exhibit excellent adsorption capacity of 103 mg·g–1to Rb metal ions and high photodegradation efficiency toward organic dyes in the presence of a lower concentration of H2O2. The experimental characterizations and DFT calculations confirmed the strong interaction of Rb metal ions on the surface of BMT-micromotors and the excellent decomposition of H2O2which enhanced the photodegradation process. We expect the combination of light and fuel sensitivity with magnetic controllability to unlock an excess of opportunities for the application of BMT-micromotors in water treatments.

Rotating drum experiments on binary mixtures of plastic spheres with wood spheres, wood cylinders, plastic cylinders, and wood cubes were investigated, respectively. A high-resolution camera was employed to record the flow behaviors of the binary mixtures. A machine learning-assisted image processing method was developed to segment the particles of different shapes, and its superiority was demonstrated by comparing the results with the pixel and artificial counting methods. This method was used to analyze the images recorded from binary mixture experiments to explore the effects of rotating speed, particle shape, and density differences on mixtures’ radial and axial mixing and segregation behavior. The results show that the particle shape and density difference significantly affect the resolution angle of the binary mixture containing plastic spheres. In the radial direction, the degree of mixing of the binary mixtures containing wood spheres and cubes is not sensitive to speed. The degree of mixing of the binary mixture containing cylindrical particles increases linearly with the rotating speed within a specific range. The particle shape significantly affects the radial segregation of the binary mixtures. In contrast, the rotating speed has a negligible effect on the radial segregation of binary mixtures containing wood spheres, cylinders, and cubes.

G-protein-coupled receptors (GPCRs) are a class of integral membrane proteins that detect environmental cues and trigger cellular responses. Deciphering the functional states of GPCRs induced by various ligands has been one of the primary goals in the field. Here we developed an effective universal method for GPCR cryo-electron microscopy structure determination without the need to prepare GPCR-signaling protein complexes. Using this method, we successfully solved the structures of the β2-adrenergic receptor (β2AR) bound to antagonistic and agonistic ligands and the adhesion GPCR ADGRL3 in the apo state. For β2AR, an intermediate state stabilized by the partial agonist was captured. For ADGRL3, the structure revealed that inactive ADGRL3 adopts a compact fold and that large unusual conformational changes on both the extracellular and intracellular sides are required for activation of adhesion GPCRs. We anticipate that this method will open a new avenue for understanding GPCR structure‒function relationships and drug development.

Abscisic acid (ABA) is a phytohormone essential to the regulation of numerous aspects of plant growth and development. The cellular level of ABA is critical to its signalling and is determined by its rate of biosynthesis, catabolism and the rates of ABA transport. ABCG25 in Arabidopsis thalianahas been identified to be an ABA exporter and play roles in regulating stomatal closure and seed germination. However, its ABA transport mechanism remains unknown. Here we report the structures of ABCG25 under different states using cryo-electron microscopy single particle analysis: the apo state and ABA-bound state of the wild-type ABCG25 and the ATP-bound state of the ATPase catalytic mutant. ABCG25 forms a homodimer. ABA binds to a cone-shaped, cytosolic-facing cavity formed in the middle of the transmembrane domains. Key residues in ABA binding are identified and verified by a cell-based ABA transport assay. ATP binding leads to closing of the nucleotide-binding domains of opposing monomers and conformational transitions of the transmembrane domains. Together, these results provide insights into the substrate recognition and transport mechanisms of ABCG25 in Arabidopsis, and facilitate our understanding of the ABA transport and signalling pathway in plants.

In recent years, there has been growing interest in the study of chiral active materials, which consist of building blocks that show active dynamics featuring chiral symmetry breaking, e.g., particles that rotate in a common direction. These materials exhibit fascinating phenomena such as odd viscosity, odd diffusivity, active turbulence in fluids, vivid dislocation dynamics or odd elasticity in crystals or elastic materials, and hyperuniform states. The systematic study of soft chiral active matter systems is relatively new, starting around 2017, but has already shown promising applications in robust cargo transport, segregation and mixing dynamics, or manipulation of metamaterials. In this review, we summarize recent experimental and theoretical advances in this field, highlighting the emergence of anti-symmetric and odd stresses and ensuring effects such as odd viscosity or topologically protected edge modes. We further discuss the underlying mechanisms and provide insights into the potential of chiral active matter for various applications.

Addressing environmental pollution, the present study proposes the utilization of natural products as alternatives to chemical additives in soap manufacturing. Specifically, the study explores the potential of the above-ground parts of Paris polyphylla(AGPP), an abundant but underexploited resource, in contrast to its overexploited and endangered underground parts of Paris polyphylla(UGPP). The AGPP was extracted with 75% (V/V) ethanol, yielding a significantly higher content of saponin VII compared to the UGPP extract (41.02 mg/g vs. 10.41 mg/g). Radical scavenging assays demonstrated the extract’s effectiveness against DPPH, hydroxyl, and superoxide anion radicals. The extract was subsequently incorporated into a soap base, optimized via D-optimal mixture design to comprise 20.5% coconut oil, 42.5% olive oil, and 37% palm oil. Antibacterial studies indicated that the soap containing AGPP extract exhibited potent activity against Candida albicansand Propionibacterium acnes. These findings suggest the promising role of AGPP extract as a natural antioxidant and antimicrobial agent in the formulation of eco-friendly soap

Polar auxin transport is unique to plants and coordinates their growth and development1,2. The PIN-FORMED (PIN) auxin transporters exhibit highly asymmetrical localizations at the plasma membrane and drive polar auxin transport3,4; however, their structures and transport mechanisms remain largely unknown. Here, we report three inward-facing conformation structures of Arabidopsis thalianaPIN1: the apo state, bound to the natural auxin indole-3-acetic acid (IAA), and in complex with the polar auxin transport inhibitor N-1-naphthylphthalamic acid (NPA). The transmembrane domain of PIN1 shares a conserved NhaA fold5. In the substrate-bound structure, IAA is coordinated by both hydrophobic stacking and hydrogen bonding. NPA competes with IAA for the same site at the intracellular pocket, but with a much higher affinity. These findings inform our understanding of the substrate recognition and transport mechanisms of PINs and set up a framework for future research on directional auxin transport, one of the most crucial processes underlying plant development.

Uncovering conserved 3D protein–ligand binding patterns on the basis of functional groups(FGs) shared by a variety of small molecules can greatly expand our knowledge of protein–ligand interactions. Despite that conserved binding patterns for a few commonly used FGs have been reported in the literature, large-scale identification and evaluation of FG-based 3D binding motifsare still lacking. Here, we propose a computational method, Automatic FG-based Three-dimensional Motif Extractor (AFTME), for automatic mapping of 3D motifs to different FGs of a specific ligand. Applying our method to 233 naturally-occurring ligands, we define 481 FG-binding motifs that are highly conserved across different ligand-binding pockets. Systematic analysis further reveals four main classes of binding motifs corresponding to distinct sets of FGs. Combinations of FG-binding motifs facilitate the binding of proteins to a wide spectrum of ligands with various binding affinities. Finally, we show that our FG–motif map can be used to nominate FGs that potentially bind to specific drug targets, thus providing useful insights and guidance for rational design of small-molecule drugs.

Uncovering conserved 3D protein–ligand binding patterns on the basis of functional groups(FGs) shared by a variety of small molecules can greatly expand our knowledge of protein–ligand interactions. Despite that conserved binding patterns for a few commonly used FGs have been reported in the literature, large-scale identification and evaluation of FG-based 3D binding motifsare still lacking. Here, we propose a computational method, Automatic FG-based Three-dimensional Motif Extractor (AFTME), for automatic mapping of 3D motifs to different FGs of a specific ligand. Applying our method to 233 naturally-occurring ligands, we define 481 FG-binding motifs that are highly conserved across different ligand-binding pockets. Systematic analysis further reveals four main classes of binding motifs corresponding to distinct sets of FGs. Combinations of FG-binding motifs facilitate the binding of proteins to a wide spectrum of ligands with various binding affinities. Finally, we show that our FG–motif map can be used to nominate FGs that potentially bind to specific drug targets, thus providing useful insights and guidance for rational design of small-molecule drugs.

Both 3-hydroxy-2-butanone and triethylamine are highly toxic and harmful to human health, and their chronic inhalation can cause respiratory diseases, eye lesions, dermatitis, headache, dizziness, drowsiness, and even fatality. Developing sensors for detecting such toxic gases with low power consumption, high response with superselectivity, and stability is crucial for healthcare and environmental monitoring. This study presents a typical gas sensor fabricated based on AuPdO modified Cu-doped K2W4O13nanowires, which can selectively detect 3-hydroxy-2-butanone and triethylamine at 120 and 200 °C, respectively. The sensor displays excellent sensing performance at reduced operating temperature, high selectivity, fast response/recovery, and stability, which can be attributed to a synergistic effect of Cu dopants and AuPdO nanoparticles on the K2W4O13host. The enhanced sensing response and selectivity could be attributed to the oxygen vacancies/defects, bandgap excitation, the electronic sensitization, the reversible redox reaction of PdO and Cu, the cocatalytic activity of AuPdO, and Schottky barrier contacts at the interface of tungsten oxide and Au. The significant variations in the activation capacities of Cu-doped K2W4O13, Pd/PdO, and Au nanoparticles toward 3H-2B and TEA, and the diffusion depth of the two gases in the coated sensing layer may cause dual selectivity. The designed gas sensor materials can serve as a sensitive target for detecting toxic biomarkers and hold broad application prospects in food and environmental safety inspection.

Purpose: The aim of this study was to investigate the changes of Helper T cells 17 (Th17 cells), Regulatory T cells (Treg cells), Treg/Th17, Interleukin-17 (IL-17) and Interleukin-10 (IL-10) in patients with type 2 diabetes mellitus (T2DM). Methods: Four electronic resource databases were searched from their inception to 1 August 2021. Case-control studies about changes of Th17 cells, Treg cells, Treg/Th17, IL-17 and IL-10 in patients with T2DM were retrieved. We performed this meta-analysis via RevMan V.5.3 and Stata14. Results: 20 studies with 1242 individuals were included in the meta-analysis. Compared with the controls, the patients with T2DM had significantly increased levels of percentage of Th17 cells (SMD, 1.74; 95% CI, 0.47–3.01; p?<?0.001), IL-17 (SMD, 2.17; 95% CI, 0.06–4.28; p?<?0.001), IL-10 (SMD, 1.20; 95% CI, 0.81–1.59; p?=?0.003), but decreased levels of percentage of Treg cells (SMD, -1.17; 95% CI, -2.22 to -0.13; p?<?0.001) and Treg/Th17 ratio (SMD, -4.43; 95% CI, -7.07 to -1.78; p?<?0.001). Subgroup analysis showed that percentage of CD4+CD25+FOXP3+Tregs (SMD, -2.36; 95% CI, -3.19 to -1.52; p?=?0.003) in patients was notably lower than controls. While not significant changes were found in the percentage of CD4+CD25+Tregs (SMD, 0.03; 95% CI, -0.34–0.40; p?=?0.63) between patients and controls. For plasma or serum IL-10, a higher plasma IL-10 level (SMD,1.37; 95% CI, 0.92–1.82; p?=?0.01) was observed in T2DM. While serum IL-10 (SMD, 0.73; 95% CI, 0.35–1.12; p?=?0.79) had no obvious difference between patients and controls. For ELISA or flow cytometry, IL-10 (SMD, 1.2; 95% CI, 0.71–1.70; p?=?0.001) was higher in T2DM patients by using detection method of ELISA. Yet IL-10 using flow cytometry and subgroup analysis of IL-17 had no significant differences. Conclusions: Adaptive immune system indeed plays an essential role in the process of T2DM. Imbalance between Th17 and Treg triggers pro-inflammatory environment in patients with T2DM.

Agkisacucetin, a snake C-type lectin-like protein isolated from the venom of Deinagkistrodon acutus (formerly Agkistrodon acutus), is a novel antithrombotic drug candidate in phase 2 clinical trials. Agkisacucetin specifically recognizes the platelet surface receptor glycoprotein Ib α chain (GPIbα) to block GPIb and von Willebrand factor (VWF). In this study, we solved the crystal structure of the GPIbα N-terminal domain (residues 1-305) in complex with agkisacucetin to understand their molecular recognition mechanism. The crystal structure showed that agkisacucetin primarily contacts GPIbα at the C-terminal part of the conserved leucine-rich repeat (LRR) domain (LRR-6 to LRR-8) and the previously described “β-switch” region through the β chain. In addition, we found that agkisacucetin α chain contacts part of the GPIbα C-terminal peptide after the LRR domain through complementary charge interactions. This C-terminal peptide plays a key role in GPIbα and thrombin recognition. Therefore, our structure revealed that agkisacucetin can sterically block the interaction between the GPIb receptor and VWF and thrombin proteins to inhibit platelet function. Our structural work provides key molecular insights into how an antithrombotic drug candidate recognizes the GPIb receptor to modulate platelet function to inhibit thrombosis.

Agkisacucetin, a snake C-type lectin-like protein isolated from the venom of Deinagkistrodon acutus(formerly Agkistrodon acutus), is a novel antithrombotic drug candidate in phase 2 clinical trials. Agkisacucetin specifically recognizes the platelet surface receptor glycoprotein Ib α chain (GPIbα) to block GPIb and von Willebrand factor (VWF). In this study, we solved the crystal structure of the GPIbα N-terminal domain (residues 1-305) in complex with agkisacucetin to understand their molecular recognition mechanism. The crystal structure showed that agkisacucetin primarily contacts GPIbα at the C-terminal part of the conserved leucine-rich repeat (LRR) domain (LRR-6 to LRR-8) and the previously described “β-switch” region through the β chain. In addition, we found that agkisacucetin α chain contacts part of the GPIbα C-terminal peptide after the LRR domain through complementary charge interactions. This C-terminal peptide plays a key role in GPIbα and thrombin recognition. Therefore, our structure revealed that agkisacucetin can sterically block the interaction between the GPIb receptor and VWF and thrombin proteins to inhibit platelet function. Our structural work provides key molecular insights into how an antithrombotic drug candidate recognizes the GPIb receptor to modulate platelet function to inhibit thrombosis.

We investigated experimentally and theoretically the interactions and assembly of rodlike colloids in a ferrofluid confined at solid/liquid interface by the gravity under external magnetic fields. We first derived analytical expressions for the interaction energy of a single rod with the external magnetic field and the interaction between two rods using classical electromagnetism. The theory well captured the experimentally observed alignment of a single rod along the field direction under an in-plane field and switching between the horizontal and the vertical configurations in an out-of-plane field due to the competition between the magnetic energy and the gravitational energy. The theory can also predict the symmetric position fluctuations of a free rod on a fixed one at 90° and the gradual bias toward the end of the fixed rod as the angle was reduced to 0°, favoring the tip-toe arrangement. Finally, we showed that this anisotropic interaction led to the formation of chain-like structures, whose growth kinetics followed a simple scaling behavior with time. This work provides a theoretical framework for understanding the behaviors of rodlike colloids in ferrofluids and highlights the importance of shape anisotropy in manipulating colloids and their self-assembly.

Viral capsid-like particles tiled with mosaic patches have attracted great attention as they imitate nature’s design to achieve advanced material properties and functions. Here, we develop a facile one-pot soft-template method to synthesize biomimetic gold capsid-like colloids with tunable particle size and surface roughness. Uniform submicron-to-micron-sized hollow gold colloidal particles are successfully achieved by using tannic acids as soft templates and reducing agents, which first self-assemble into spherical complex templates before the reduction of Au3+ions via their surface hydroxyl groups. The surface roughness, the size, and the total number of the patches of the prepared gold particles are further tuned, utilizing a mechanism that offers morphology control by varying the number of surface hydroxyl groups participating in the reduction reactions. Among different capsid-like gold colloids, those possessing a rough surface display superior catalytic properties and show promising results as surface-enhanced Raman spectroscopy (SERS) solid substrates for detecting small organic molecules and biomimetic enzymes in a liquid phase for sensing biomolecules in real samples. These capsid-like gold colloids are also expected to find practical applications in delivery systems, electronics, and optics. We believe that our strategy of imitating nature’s design of capsid-like structures should also be used in the design and fabrication of other functional colloidal particles.

Spatiotemporal coordination of a nanorobot ensemble is critical for their operation in complex environments, such as tissue removal or drug delivery. Current strategies of achieving this task, however, rely heavily on sophisticated, external manipulation. We here present an alternative, biomimetic strategy by which oscillating Ag Janus micromotors spontaneously synchronize their dynamics as chemically coupled oscillators. By quantitatively tracking the kinetics at both an individual and cluster level, we find that synchronization emerges as the oscillating entities are increasingly coupled as they approach each other. In addition, the synchronized beating of a cluster of these oscillating colloids was found to be dominated by substrate electroosmosis, revealed with the help of an acoustic trapping technique. This quantitative, systematic study of synchronizing micromotors could facilitate the design of biomimetic nanorobots that spontaneously communicate and organize at micro- and nanoscales. It also serves as a model system for nonlinear active matter.

Aim and Objective: This study was designed to explore the active compounds and significant pathways of Guizhi-Shaoyao-Zhimu decoction (GSZD) for treating diabetes mellitus using molecular docking combined with network pharmacology. Materials and Methods: Chemical constituents of GSZD and diabetes-related target proteins were collected from various databases. Then, compounds were filtered by Lipinski’s and Veber’s rules with Discovery studio software. The “Libdock” module was used to carry out molecular docking, and LibDockScores, default cutoff values for hydrogen bonds, and van der Waals interactions were recorded. LibDockScore of the target protein and its prototype ligand was considered as the threshold, and compounds with higher LibDockScores than the threshold were regarded as the active constituents of GSZD. Cytoscape software was used to construct the herb-active molecule-target interaction network of GSZD. ClueGO and CluePedia were applied to enrich the analysis of the biological functions and pathways of GSZD. Results: A total of 275 potential active compounds with 57 possible pathways in GSZD were identified by molecular docking combined with network pharmacology. TEN, INSR, PRKAA2, and GSK3B are the four most important target proteins. Gancaonin E, 3'-(γ,γ-dimethylallyl)-kievitone, aurantiamide, curcumin and 14-O-cinnamoylneoline, could interact with more than 14 of the selected target proteins. Besides, 57 potential pathways of GSZD were identified, such as insulin signaling pathway, metabolites and energy regulation, glucose metabolic process regulation, and positive regulation of carbohydrate metabolic process, etc. Conclusion: These results showed that molecular docking combined with network pharmacology is a feasible strategy for exploring bioactive compounds and mechanisms of Chinese medicines, and GSZD can be used to effectively treat diabetes through multi-components and multi-targets & pathways.

The absorption of gas molecules at hydrophobic surfaces may have a special state and play an important role in many processes in interfacial physics, which has been rarely considered in previous theory. In this paper, force spectroscopic experiments were performed by a nanosized AFM probe penetrated into individual surface nanobubbles and contacted with a highly ordered pyrolytic graphite (HOPG) substrate. The results showed that the adhesion force at the gas/solid interface was much smaller than that in air measured with the same AFM probe. The adhesion data were further analyzed by the van der Waals force theory, and the result implied that the gas density near the substrate inside the surface nanobubbles was about 3 orders of magnitude higher than that under the standard pressure and temperature (STP). Our MD simulation indicated that the gas layers near the substrate exhibited a high-density state inside the surface nanobubbles. This high-density state may provide new insight into the understanding of the abnormal stability and contact angle of nanobubbles on hydrophobic surfaces, and have significant impact on their applications.

ABSTRACTPrecision farming based on soil total nitrogen status is crucial to informed fertilization strategies while enhancing environmental quality of agricultural ecosystems. Hyperspectral technology was applied for rapid assessment of soil total nitrogen content in a long-term fertilization experiment of wheat-corn rotation system. The first-order derivative of squared spectra and Soil Adjusted Spectral Index transformation provided the highest correlation with soil total nitrogen contents. Inversion modeling results involving multiple linear regression, back propagation neural network (BPNN), and partial least square regression indicated that BPNN provided the best performance with coefficient of determination (R2) reaching 0.8 and 0.9, respectively, for wheat and corn seasons. Model performance with wheat and corn season combined was poor due to seasonal difference in hyperspectral patterns and different decomposition of straws returned to the field. This study provided a quantitative tool for rapid and accurate diagnosis of soil total nitrogen content for precision agriculture.

Aerogel with ultra-lightweight, special wettability and porous structure played a potential role in the separation of oil layer/water mixture. In this research cost-effective mesoporous three-dimensional (3D) aerogel was designed and fabricated through a simple and green hydrothermal, synthetic method as a sorbent for efficient treatment of emulsified oil. The -prepared grapefruit peel aerogel exhibits mesoporous structures (2–50 nm) with an average pore size/diameter of 10.21 nm, a surface area of 17.31 m2/g and pore volume up to 0.0321 cm3/g. Excellent hydrophobicity of DMS-MGA aerogel with a water contact angle of 143.1° depicting great potential of this material for effective separation of water-oil emulsion. Furthermore, the prepared aerogel displayed excellent regeneration capability of more than 98% after eight cycles of sorption–regeneration. The carbonization process destroyed graphite crystals, and a new peak confirmed the alteration. PDMS raised crystallinity indices to 86%. Raman spectroscopy also revealed two peaks at 1498 and 1588 cm−1linked with carbon's D and G bands. The effective grafting of dimethyl siloxane on DMS-MGA surface resulted in two new strong bands in the FT-IR spectra at 1254 cm−1(C-H in Si-CH3) and 796 cm−1(Si-O). TGA showed that the total carbon output was 28.5%, which is indicative of its good stability at elevated temperatures. DMS-MGA demonstrated near-complete sorption at a neutral pH of 7 of a crude oil-in-water emulsions. After 15 sorption-regeneration cycles, DMS-MGA still had a sorption efficiency of more than 95% despite being in contact with oil, and its anti-compression stability hadn't changed in the slightest.

Colloidal shuttles are micro/nanoscale motors that display controllable cargo loading/release and programmable navigation, which are emerging delivery vehicles at the small scale. Here we present a hydrogen peroxide-fueled catalytic colloidal shuttle composed of a hematite cube half coated with platinum, i.e. a Pt/hematite Janus cube, which can be remotely controlled with ease by light and magnetic field. Interestingly, the dynamic behaviors of the Pt/hematite motor under light illumination in lower fuel concentration are similar to those Pt-based motors in higher fuel concentration without UV light, including the self-propulsion direction and the interaction with passive particles. In lower fuel concentration, we demonstrate the ability of the Pt/hematite motor for light-switchable cargo loading and release, and programmable and directional transportation of cargoes using the intrinsic magnetic property of hematite. Our work offers an efficient colloidal shuttle that operates at favorable fuel concentration and light intensity in comparison to earlier reported cargo-towing colloidal motors, which should find applications as microscale delivery vehicles, particularly for cargo transportation on microchips.

The phytohormone auxin plays central roles in many growth and developmental processes in plants. Development of chemical tools targeting the auxin pathway is useful for both plant biology and agriculture. Here we reveal that naproxen, a synthetic compound with anti-inflammatory activity in humans, acts as an auxin transport inhibitor targeting PIN-FORMED (PIN) transporters in plants. Physiological experiments indicate that exogenous naproxen treatment affects pleiotropic auxin-regulated developmental processes. Additional cellular and biochemical evidence indicates that naproxen suppresses auxin transport, specifically PIN-mediated auxin efflux. Moreover, biochemical and structural analyses confirm that naproxen binds directly to PIN1 protein via the same binding cavity as the indole-3-acetic acid substrate. Thus, by combining cellular, biochemical, and structural approaches, this study clearly establishes that naproxen is a PIN inhibitor and elucidates the underlying mechanisms. Further use of this compound may advance our understanding of the molecular mechanisms of PIN-mediated auxin transport and expand our toolkit in auxin biology and agriculture.

Colloids that are able to navigate via predefined paths and adapt to complex environments hold great promises as miniaturized machines and model systems for active soft matter research. Here, we design an intelligent system that integrates dynamic magnetic field and light control with in-situ determination of particle position and velocity via Matlab-based image acquisition and analysis. We apply the system to realize programmable and feedback control over the motion of a magnetic and photoactive colloid. Specifically, we direct the active colloid into pentagram-like navigation, circular motion of various size, and spiral-like motion by changing the travelling direction, discretely or continuously, the self-propelled velocity, and a combination of the two, enabled by dynamic change of magnetic field, light intensity and both. Moreover, we demonstrate the ability of the system for on-the-fly self-correction to follow predefined path with high fidelity, and adaptability to complex surroundings with definable birdlike vision based on in-situ processing of information. We expect the programmability and adaptability of magnetic and photoactive colloids enabled by multiple handles, magnetic field and light, open up new opportunities for active soft matter research, including intelligent microrobotics, collective nonequilibrium dynamics and novel photonic fluids.

Enolase is a highly conserved enzyme that presents in all organisms capable of glycolysis or fermentation. Its immediate product phosphoenolpyruvate is essential for other important processes like peptidoglycan synthesis and the phosphotransferase system in bacteria. Therefore, enolase inhibitors are of great interest. Here, we report that Gp60, a phage-encoded enolase inhibitor protein (PEIP) of bacteriophage SPO1 for Bacillus subtilis, is an enolase inhibitor. PEIP-expressing bacteria exhibit growth attenuation, thinner cell walls, and safranin color in Gram staining owing to impaired peptidoglycan synthesis. We solve the structure of PEIP-enolase tetramer and show that PEIP disassembles enolase by disrupting the basic dimer unit. The structure reveals that PEIP does not compete for substrate binding but induces a cascade of conformational changes that limit accessibility to the enolase catalytic site. This phage-inspired disassembly of enolase represents an alternative strategy for the development of anti-microbial drugs.

Solid concentration and particle velocity distributions in the transition section of a ϕ200mm turbulent fluidized bed (TFB) and a ϕ200mm annulus turbulent fluidized bed (A-TFB) with a ϕ50mm central standpipe were measured using a PV6D optical probe. It is concluded that in turbulent regime, the axial distribution of solid concentration in A-TFB was similar to that in TFB, but the former had a shorter transition section. The axial solid concentration distribution, probability density, and power spectral distributions revealed that the standpipe hindered the turbulence of gas–solid two-phase flow at a low superficial gas velocity. Consequently, the bottom flow of A-TFB approached the bubbling fluidization pattern. By contrast, the standpipe facilitated the turbulence at a high superficial gas velocity, thus making the bottom flow of A-TFB approach the fast fluidization pattern. Both the particle velocity and solid concentration distribution presented a unimodal distribution in A-TFB and TFB. However, the standpipe at a high gas velocity and in the transition or dilute phase section significantly affected the radial distribution of flow parameters, presenting a bimodal distribution with particle concentration higher near the internal and external walls and in downward flow. Conversely, particle concentration in the middle annulus area was lower, and particles flowed upward. This result indicated that the standpipe destroyed the core-annular structure of TFB in the transition and dilute phase sections at a high gas velocity and also improved the particle distribution of TFB. In conclusion, the standpipe improved the fluidization quality and flow homogeneity at high gas velocity and in the transition or dilute phase section, but caused opposite phenomena at low gas velocity and in the dense-phase section.

Classic binary materials, ranging from polymer blends to table salts, contain equilibrium phases or crystals of two interacting components. Here, we report on the construction of binary colloidal materials out of equilibrium by employing active particles and passive particles that dynamically interact and organize. Key to our scheme is the introduction of photoactive microspheres whose activity can be precisely tuned. This allows us to leverage the complex nonequilibrium interplay between the constituent components for dynamic coassembly. A wide variety of binary structures have thus been realized, including the liquid–crystal phases and crystal–crystal phases viaphase separation and, counterintuitively, the binary crystalline compounds. The obtained structures are validated by computer simulations, which reveal unexpected kinetic pathways that are unique for active systems. With these findings, our strategy could facilitate the design and fabrication of multicomponent materials beyond equilibrium.

It has been suggested that irreversible adsorption at the gas/liquid interface of bulk nanobubbles will reduce the Laplace pressure, leading to their stability. However, most previous studies have focused on the stability of individual nanobubbles. Bulk nanobubbles are polydispersed suspensions, and gas molecules can diffuse between bubbles, leading to their collective dynamics, which may be crucial to understanding their formation process and stability. In this study, we proposed a mean-field theory for computing the evolution of the size-distribution function of bulk nanobubbles with size-dependent surface tension. We applied this theory to investigate the evolution of bulk nanobubbles with insoluble surfactants pinned at their gas/water interface. The results show that Ostwald ripening can be suppressed when enough surfactants are adsorbed. Bulk nanobubbles can be produced by the shrinkage of microbubbles in an air-saturated solution. The mean stable size is controlled by the amount of surfactants and the initial microbubble concentration; these predictions are qualitatively consistent with the experimental results of micro/nanobubbles produced using the microfluidic method.

Light-powered fuel-free colloidal motors possess significant potential for practical applications ranging from nanomedicine to environmental remediation. However, current light-powered colloidal motors often require the incorporation of expensive metals or high concentrations of toxic chemical fuels, which is a severe limitation for their practical applications. Integrating highly ordered and porous materials with a large surface area into colloidal motors is a promising strategy for upsurging their self-propelled speed and adsorption, which will benefit many applications. Here, highly efficient, fuel-free, and light-activated metal organic framework (MOF)-3-trimethoxysilyl propyl methacrylate Janus colloidal motors with a hierarchical morphology are reported. These colloidal motors can be driven by UV or visible light, with a self-propelled speed tuned by the light intensity. The speed can be further enhanced by morphology optimization or by the addition of H2O2as a fuel. The colloidal motors display a superior efficiency in removing heavy metal ions of Hg, which is up to ∼90% within 40 min from the contaminated water, attributed to their high surface area, hierarchical morphology, large number of active sites, and high mobility. This work not only offers a facile approach to incorporate a versatile MOF family into the design of fuel-free and light-powered Janus colloidal motors, but also demonstrates their potential for real-life applications such as environmental remediation.