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Metastable supramolecular polymerization under kinetic control has recently been recognized as a closer way to biosystem than thermodynamic process. While impressive works on metastable supramolecular systems have been reported, the library of available non-covalent driving modes is still small and a simple yet versatile solution is highly desirable to design for easily regulating the energy landscapes of metastable aggregation. Herein, we propose a coopetition-driven metastability strategy for parallel/perpendicular aromatic stacking to construct metastable supramolecular polymers derived from a class of simple monomers consisting of lateral indoles and aromatic core. By subtly increasing the stacking strength of aromatic cores from phenyl to anthryl, the parallel face-to-face stacked aggregates are competitively formed as metastable products, which spontaneously transform into thermodynamically favorable species through the cooperativity of perpendicular edge-to-face stacking and parallel offset stacking. The slow kinetic-to-thermodynamic transformation could be accelerated by adding seeds for realizing the desired living supramolecular polymerization. Besides, this transformation of parallel/perpendicular aromatic stacking accompanied by time-dependent emission change from red to yellow is employed to dynamic cell imaging, largely avoiding the background interferences. The coopetition relationship of different aromatic stacking for metastable supramolecular systems is expected to serve as an effective strategy towards pathway-controlled functional materials. Metastable supramolecular polymerization under kinetic control is a closer way to biosystem than thermodynamic process but the library of available non-covalent driving modes is small. Here, the authors propose a coopetition-driven metastability strategy for parallel/perpendicular aromatic stacking to construct metastable supramolecular polymers.

Nonconventional luminescent materials have been rising stars in organic luminophores due to their intrinsic characteristics, including water‐solubility, biocompatibility, and environmental friendliness and have shown potential applications in diverse fields. As an indispensable branch of nonconventional luminescent materials, polysiloxanes, which consist of electron‐rich auxochromic groups, have exhibited outstanding photophysical properties due to the unique silicon atoms. The flexible Si‐O bonds benefit the aggregation, and the empty 3d orbitals of Si atoms can generate coordination bonds including N → Si and O → Si, altering the electron delocalization of the material and improving the luminescent purity. Herein, we review the recent progress in luminescent polysiloxanes with different topologies and discuss the challenges and perspectives. With an emphasis on the driving force for the aggregation and the mechanism of tuned emissions, the role of Si atoms played in the nonconventional luminophores is highlighted. This review may provide new insights into the design of nonconventional luminescent materials and expand their further applications in sensing, biomedicine, lighting devices, etc. This review summarizes recent progress in nonconventional luminescent polysiloxanes with AIE characteristics and discusses the challenges and perspectives. Considering the significant influence of polymer topologies on their luminescent features, we focus on the driving force for the aggregation and the mechanism of tuned emissions, as well as the role of Si atoms played in these nonconventional luminophores.

The tolerance of critical components in five-axis machine tools directly impacts the overall machining accuracy of the entire system. This paper presents a tolerance optimization method for machine tools that is grounded in sensitivity theory and the NSGA-II algorithm. First, a mapping model is established to relate tolerance parameters to geometric and spatial motion errors. Second, a gradient-based sensitivity index, which has a clear physical interpretation and high computational efficiency, is defined to quantify the influence of individual tolerances on the spatial motion errors. Recognizing the limitations of existing tolerance allocation methods, this study introduces the innovative concept of tolerance control cost (the sum of the products of tolerance sensitivity and tolerance value for each parameter), and an optimization model is formulated to minimize this while ensuring the spatial motion error meets the requirement. The NSGA-II algorithm is employed to solve this model. Simulation results demonstrate that the tolerances of components can be significantly relaxed (thereby indirectly reducing manufacturing costs) while still ensuring the desired spatial motion error of the entire machine, validating the feasibility and effectiveness of the proposed method.

Elite controllers (ECs) and post-treatment controllers (PTCs) represent important models for achieving a functional cure for HIV. This review synthesizes findings from immunological, genetic, and virological studies to compare the mechanisms underlying HIV suppression in ECs and PTCs. Although ECs maintain viral control without antiretroviral therapy (ART), PTCs achieve suppression following ART discontinuation. Both groups rely on adaptive and innate immunity, host genetic factors, and characteristics of the HIV reservoir; however, they exhibit distinct immune responses and genetic profiles. These differences provide insights into strategies for sustained ART-free remission. Understanding the shared and unique mechanisms in ECs and PTCs can inform the development of novel therapeutic approaches, including immune-based therapies and genome editing, to achieve a functional cure for HIV-1.

Syphilis, caused by Treponema pallidum ( T. pallidum ), represents a significant worldwide public health threat. This spiral-shaped, Gram-negative pathogen is a strict human-specific obligate parasite primarily transmitted through sexual contact. This pathogen induces a multistage and multisystem progressive disease, against which no effective prophylactic vaccine currently exists. This study focuses on syphilis prevention and control by employing a reverse vaccinology approach to investigate the immunogenic properties of T. pallidum adhesin proteins. Fifteen T-cell epitopes and seven B-cell epitopes were screened and linked in series using appropriate linkers to construct a multi-epitope vaccine. The vaccine was subjected to in silico analysis, including secondary and tertiary structure prediction, molecular docking, and molecular dynamics simulation. Based on these analyses, a recombinant plasmid, pET-28a(+)-MEVTP, was constructed, and the purified recombinant protein was obtained via nickel column affinity chromatography. In silico immune simulation results suggested that the vaccine could induce specific cellular and humoral immune responses. However, further experimental evaluation of its immunological effects is required to validate the computationally predicted immunogenicity, thereby establishing an experimental basis for its advancement toward translational medical applications and providing critical evidence to support syphilis prevention and control efforts.

A 58-year-old man who lived in northern China was presented to the dermatology clinic with an asymptomatic cutaneous lesion on his right forearm that had been present for at least a month. He was a shepherd, and reported that some of his sheep had developed cutaneous lesions around their mouths 6 weeks previously. When he was examined, they saw an erythematous ulcerative lesion of 1.2 cm in diameter. They swabbed the lesion for a polymerase chain reaction test for orf virus, which returned a positive result. They diagnosed orf virus infection. They did not prescribe any treatment, but instructed the patient to keep the lesion clean. When they saw him 2 months later, the lesions had resolved, and no new lesions had developed. The orf virus is a DNA virus that belongs to the Parapoxvirus genus of the Poxviridae family. Sheep and goats are its natural hosts. Orf virus infection in humans almost always occurs when broken skin comes in contact with an infected animal or contaminated equipment. The incidence of human infection with orf in Canada is not known, but in a farming community from the UK, about 30% of sheep workers reported having been infected.

L-arginine, a basic amino acid, exhibits high biocompatibility, reactivity, and absorbability. It was selected as the co-polymer modification monomer for L-lactic acid with the objective of enhancing the hydrophilicity of poly(lactic acid) (PLA), neutralizing the acidity of PLA degradation products, and regulating the degradation cycle. The copolymer poly(lactic acid-co-arginine) (PLAA) was synthesized by direct melting polycondensation of L-arginine and L-lactic acid, and the structures and properties of PLAA were characterized. The results indicated the presence of –NH2, –NH–, and NH= in the molecular chain of the copolymer PLAA. Furthermore, the PLAA was identified as an amorphous copolymer. The “PLAA/CHCl3/C6H14” ternary phase diagram was constituted by nonsolvent-induced phase separation (NIPS) by selecting chloroform (CHCl3) as a good solvent and n-hexane (C6H14) as a nonsolvent. The phase diagram displays three distinguishable regions: the homogeneous zone, the metastable zone, and the phase separation zone. These regions are identified by the binodal and spinodal curves. The ternary phase diagram establishes a theoretical foundation for the preparation and processing of PLAA nanoparticles, composite materials, and porous fibers or membranes.

Degradation and reprocessing of thermoset polymers have long been intractable challenges to meet a sustainable future. Star strategies via dynamic cross‐linking hydrogen bonds and/or covalent bonds can afford reprocessable thermosets, but often at the cost of properties or even their functions. Herein, a simple strategy coined as hyperbranched dynamic crosslinking networks (HDCNs) toward in‐practice engineering a petroleum‐based epoxy thermoset into degradable, reconfigurable, and multifunctional vitrimer is provided. The special characteristics of HDCNs involve spatially topological crosslinks for solvent adaption and multi‐dynamic linkages for reversible behaviors. The resulting vitrimer displays mild room‐temperature degradation to dimethylacetamide and can realize the cycling of carbon fiber and epoxy powder from composite. Besides, they have supra toughness and high flexural modulus, high transparency as well as fire‐retardancy surpassing their original thermoset. Notably, it is noted in a chance‐following that ethanol molecule can induce the reconstruction of vitrimer network by ester‐exchange, converting a stiff vitrimer into elastomeric feature, and such material records an ultrahigh modulus (5.45 GPa) at −150 °C for their ultralow‐temperature condition uses. This is shaping up to be a potentially sustainable advanced material to address the post‐consumer thermoset waste, and also provide a newly crosslinked mode for the designs of high‐performance polymer. Hyperbranched dynamic crosslinking networks (HDCNs) convert a thermoset network from permanently three‐dimensional‐structure to dynamically topological‐crosslinked architecture, programming a petroleum‐based thermoset into degradable, reconfigurable and multifunctional vitrimer. They are capable of room‐temperature degradation to solvent, and exhibit reconfigurability from stiff vitrimer to elastomer. Vitrimers also display enhanced modulus, toughness, flame‐retardancy, and high transparency when compared to native commodity thermosets.

Crosslinking thermosets with hyperbranched polymers confers them superior comprehensive performance. However, it still remains a further understanding of polymer crosslinking from the molecular chains to the role of aggregates. In this study, three hyperbranched polysiloxane structures (HBPSi‐R) are synthesized as model macromolecules, each featuring distinct terminal groups (R denotes amino, epoxy, and vinyl groups) while similar molecular backbone (Si‐O‐C). These structures were subsequently copolymerized with epoxy monomers to construct interpenetrating HBPSi‐R/epoxy/anhydride co‐polymer systems. The spatial molecular configuration and flexible Si‐O‐C branches of HBPSi‐R endow them with remarkable reinforcement and toughening effects. Notably, an optimum impact strength of 28.9 kJ mol−1 is achieved with a mere 3% loading of HBPSi‐V, nearly three times that of the native epoxy (12.9 kJ mol−1). By contrasting the terminal effects, the aggregation states and crosslinking modes were proposed, thus clarifying the supramolecular‐dominant aggregation mechanism and covalent‐dominant dispersion mechanism, which influences the resulting material properties. This work underscores the significance of aggregate science in comprehending polymer crosslinking and provides theoretical insights for tailoring material properties at a refined molecular level in the field of polymer science. This study presents a novel perspective towards the understanding of polymer crosslinking from individual molecular chains to the role of aggregates. The aggregate states and crosslinking modes are proposed by engineering amino, epoxy and vinyl terminals upon hyperbranched structures. Benefiting spatial molecular configuration and flexible Si‐O‐C branches, these hyperbranched structures demonstrate exceptional enhancements in both strength and toughness, and among other superior features, striking a delicate balance between dispersion and aggregation, as well as forming robust nano‐interfaces. This research emphasizes the significance of aggregate science in comprehending the intricacies of polymer crosslinking and offers valuable theoretical insights for tailoring material properties at a refined molecular level.

Owing to its designability and intrinsic fluorescence, non‐conjugated hyperbranched polysiloxane (HBPSi) has attracted widespread attention in biological filed, while it is still severely restricted by low fluorescence efficiency. So, in this paper, we introduced disulfide into HBPSi improving their luminescence properties and synthesized different molecular weight HBPSi (P1, P2, and P3). Surprisingly, P1 exhibited ultrahigh quantum yield up to 47.81%. Meanwhile, experiments applied with theoretical calculations were employed to explore the fluorescence mechanism, which is attributed to efficient restricting of non‐radiative decay by clusteroluminogens formed with the cooperation of hyperbranched structure and double hydrogen bonding. In addition, the biocompatibility of P1 was verified by co‐culture with MC3T3‐E1 and P1 lighted up mouse fibroblast cells without fluorescent dyes. This work designed a novel fluorescent polymer with ultrahigh fluorescence quantum yield and cell imaging ability, which is promising in visualization diagnosis and treatment of tumor. Hyperbranched polysiloxane (P1) with high quantum yield up to 47.81% was synthesized, in which the groups of –Si–O–, –C=C–, –C(O)O–, and –S–S– in the aggregate work together to form clusteroluminogens to limit non‐radiative decay. In addition, P1 lights up osteoblasts and its biosafety is validated.