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Online health communities (OHCs) function as significant platforms that people use to obtain information and emotional support. Despite many studies on user behavior and relationships, little attention has been paid to user identities and how different layers of identities are interwoven. To address this potential research gap, this study examined users' relationship‐layer identities and their evolution by elaborating on the communication theory of identity (CTI) and social support theory. Additionally, based on our previous study on users' personal‐layer identities in OHCs, we investigated how users' relationship‐layer identities interacted with their personal‐layer identities. This study classified users' posts and replies into providing informational support, seeking informational support, providing emotional support, seeking emotional support, and companionship using the bidirectional encoder representation from transformers (BERT), with F1‐scores above 0.848. Through social network analysis, this study found that users of OHCs constructed their relationship‐layer identities more through informational interactions than through emotional interactions. Users with various personal‐layer identities presented different relationship‐layer identities. Users' relationships were more initiated by information exchange, and users with more interactions had more companionship activities. OHCs provided efficient communication channels for people to exchange social support. [ABSTRACT FROM AUTHOR]

Pine wilt disease, caused by Bursaphelenchus xylophilus, is a major quarantine forest disease that has resulted in massive economic losses as well as ecological disaster. Therefore, it is imperative to study the defence response mechanism of host pine trees to infection by B. xylophilus to understand further the internal causes of pine tree death and to find control strategies. For many years, systematic research has been carried out on the pathophysiological response of pine trees to pine wilt disease. However, due to the complexity of the occurrence and development of pine wilt disease, the specific response mechanisms of different tree species have remained unclear. This paper attempts to provide an overview of the resistance mechanism of host pine trees against B. xylophilus infection through the perspectives of histopathological characteristics, physiological and biochemical responses, and molecular response mechanisms, which provide a theoretical reference for further investigating the disease resistance mechanism of pine trees to pine wilt disease and lay the foundation for the prevention and quarantine of pine wilt disease. [ABSTRACT FROM AUTHOR]

4D printing technologies are currently suffering from the inability to produce rapid motions, which limit their applications that require fast shape transformation such as rapid unlocking and deployment of aerospace equipment. Herein, inspired by the shooting mechanisms of Viola verecunda fruit for seed dispersal, the 4D‐printed biomimetic catapult is developed. Based on the structure change characteristics of gradient fan‐shaped cells of the fruit pods during seed ejection, the biomimetic smart catapult is processed via the programming of spatial distribution of heterogeneous materials with various storage modulus enabled by additive manufacturing. This catapult can achieve high‐speed ejection with the logically stimuli of external force, temperature, light, humidity, or electricity. The proposed biomimetic 4D printing strategy has broken through the limitations in motion speed, which helps fully unleash the potential of 4D printing. [ABSTRACT FROM AUTHOR]

Peptide‐drug conjugates (PDCs) are an important class of therapeutic agents that combine one or more active molecules with a short peptide via a biodegradable spacer to generate prodrugs. Here an antioxidant (i.e., 3,5‐dihydroxybenzoic acid), a non‐steroidal anti‐inflammatory drug (i.e., ibuprofen, IPF), and a self‐assembled peptide motif (i.e., Gly‐Phe‐Phe‐Tyr‐Asp, GFFYD) are integrated to produce a peptide‐drug amphiphile, which self‐assembles to form hydrogel and further exerts the synergistic effects, and consequently emerges high therapeutic efficacy. In the in vitro study toward lipopolysaccharide‐activated RAW264.7 macrophages, the resulting hydrogel significantly reduces the production of cytokines (e.g., IL‐1β, IL‐6 and tumor necrosis factor‐α (i.e., TNF‐α)) compared with that of native IPF via the inhibition of nuclear factor‐κB (i.e., NF‐κB), janus kinase‐signal transducer and activator of transcription (i.e., JAK‐STAT) signals and NLR family pyrin domain containing 3 (i.e., NLRP3) inflammasome activation. Moreover, a rabbit model of endotoxin induced uveitis evidences the superior therapeutic efficacy of the resulting hydrogel over that of clinically used 0.1 wt% diclofenac sodium eyedrop. Overall, this work offers new insights into the anti‐inflammatory mechanism of PDCs hydrogel and presents the therapeutic values in the treatment of ocular disorders, and ultimately fulfils the potential clinical benefits of PDCs. [ABSTRACT FROM AUTHOR]

The fatigue performance of different warm‐mix recycled asphalt mixtures was evaluated by the semicircular bend (SCB) test. A delayed oven heating (DOH) method was developed to simulate the long‐term ageing in the laboratory. The effects of recycling plans, reclaimed asphalt pavement (RAP) content, and ageing levels on the tensile strength and fatigue resistance were investigated. The fatigue life of the warm‐mix recycled asphalt mixture was characterized by the phenomenological, dissipated energy, and the ratio of dissipated energy change (RDEC) models, respectively. The results show that the use of the warm‐mix asphalt (WMA) technology causes a reduction of the fatigue performance for the recycled asphalt mixture, which can be compensated by the addition of styrene–butadiene rubber (SBR) latex. As the RAP content or long‐term ageing time increases, the fatigue life significantly decreases. The dissipated energy model with the unified model coefficients can predict the fatigue lives for different warm‐mix recycled asphalt mixtures. HIGHLIGHTS: Fatigue performance of warm‐mix recycled asphalt mixtures was evaluated.A delayed oven heating method was developed to simulate the ageing in the laboratory.Effects of recycling plans, RAP content, and ageing levels were investigated.Different fatigue models were compared to predict fatigue lives of recycled mixtures. [ABSTRACT FROM AUTHOR]

Changing an oxygen atom of the phosphoester bond in phosphopeptides by a sulfur atom enables instantly targeting Golgi apparatus (GA) and selectively killing cancer cells by enzymatic self‐assembly. Specifically, conjugating cysteamine S‐phosphate to the C‐terminal of a self‐assembling peptide generates a thiophosphopeptide. Being a substrate of alkaline phosphatase (ALP), the thiophosphopeptide undergoes rapid ALP‐catalyzed dephosphorylation to form a thiopeptide that self‐assembles. The thiophosphopeptide enters cells via caveolin‐mediated endocytosis and macropinocytosis and instantly accumulates in GA because of dephosphorylation and formation of disulfide bonds in Golgi by themselves and with Golgi proteins. Moreover, the thiophosphopeptide potently and selectively inhibits cancer cells (HeLa) with the IC50 (about 3 μM), which is an order of magnitude more potent than that of the parent phosphopeptide. [ABSTRACT FROM AUTHOR]

This paper investigates adaptive tracking control in task space for robot manipulators with uncertain system dynamics, input saturation, and time‐varying output constraints simultaneously. An auxiliary system is constructed to compensate the effect of the input saturation, and an asymmetric barrier Lyapunov function (BLF) is applied to tackle time‐varying output constraints, while radial basis function (RBF) neural networks (NN) are used to approximate the unknown closed‐loop dynamics. By introducing a disturbance observer (DO), unknown external disturbances from humans and environment are estimated, and NN approximation errors are compensated. A novel adaptive NN tracking controller is designed to guarantee all signals in the closed‐loop system are semi‐globally uniformly ultimately bounded (UUB), while the tracking errors and observer errors converge to a small neighborhood of zero, and the time‐varying output constraints are not violated. Moreover, the adaptive tracking control of redundant robot manipulators is studied, and the subtask and task space tracking of redundant robot manipulators are realized simultaneously, while the stability of the system is proved by Lyapunov stability theory. Finally, some simulation results are presented to verify the effectiveness and superiority of the proposed control scheme. [ABSTRACT FROM AUTHOR]

Although lipids contribute to cancer drug resistance, it is challenging to target diverse range of lipids. Here, we show enzymatically inserting exceedingly simple synthetic lipids into membranes for increasing membrane tension and selectively inhibiting drug resistant cancer cells. The lipid, formed by conjugating dodecylamine to d‐phosphotyrosine, self‐assembles to form micelles. Enzymatic dephosphorylation of the micelles inserts the lipids into membranes and increases membrane tension. The micelles effectively inhibit a drug resistant glioblastoma cell (T98G) or a triple‐negative breast cancer cell (HCC1937), without inducing acquired drug resistance. Moreover, the enzymatic reaction of the micelles promotes the accumulation of the lipids in the membranes of subcellular organelles (e.g. endoplasmic reticulum (ER), Golgi, and mitochondria), thus activating multiple regulated cell death pathways. This work, in which for the first time membrane tension is increased to inhibit cancer cells, illustrates a new and powerful supramolecular approach for antagonizing difficult drug targets. [ABSTRACT FROM AUTHOR]

Antimicrobial drug resistance demands novel approaches for improving the efficacy of antibiotics, especially against Gram‐negative bacteria. Herein, we report that conjugating a diglycine (GG) to an antibiotic prodrug drastically accelerates intrabacterial ester‐bond hydrolysis required for activating the antibiotic. Specifically, the attachment of GG to chloramphenicol succinate (CLsu) generates CLsuGG, which exhibits about an order of magnitude higher inhibitory efficacy than CLsu against Escherichia coli. Further studies reveal that CLsuGG undergoes rapid hydrolysis, catalyzed by intrabacterial esterases (e.g. BioH and YjfP), to generate chloramphenicol (CL) in E. coli. Importantly, the conjugate exhibits lower cytotoxicity to bone marrow stromal cells than CL. Structural analogues of CLsuGG indicate that the conjugation of GG to an antibiotic prodrug is an effective strategy for accelerating enzymatic prodrug hydrolysis and enhancing the antibacterial efficacy of antibiotics. [ABSTRACT FROM AUTHOR]

This work aims to study the alkali‐silica reaction (ASR) with incorporated kinetic‐thermodynamic analysis. The model reactant tests were first conducted to study the silica dissolution in the simulated pore solution under different temperatures. Then, the kinetic model for silica dissolution was further improved by considering the influence of effective surface area. The improved kinetic model was also incorporated into the GEMS thermodynamic simulation. The model analysis demonstrated the silica dissolution rate is decreased mainly caused by reduced hydroxyl activity with increased saturation degree. The dissolved silica first reacted with the portlandite phase and formed the Calcium–Silicate–Hydrate (CSH) gel. The ASR gel can only be generated under high silicate ion concentration after the consumption of portlandite. [ABSTRACT FROM AUTHOR]

Abstract: In a model study to investigate the consequence of reactions of intrinsically disordered regions (IDRs) of proteins in the context of the formation of highly ordered structures, we found that enzymatic reactions control the secondary structures of peptides during assembly. Specifically, phosphorylation of an α‐helix‐dominant peptide results in mostly disordered conformations, which become β‐strand‐dominant after enzymatic dephosphorylation to regenerate the peptide. In the presence of another peptide largely with a β‐strand conformation, direct coassembly of the peptides results in amorphous aggregates consisting of α‐helix and β‐strand peptides, but the enzymatically generated peptide coassemblies (from the phosphopeptide) mainly adopt a β‐strand conformation and form ordered structures (e.g., nanofibers). These results indicate that enzymatic dephosphorylation instructs conformationally flexible peptides to adopt thermodynamically favorable conformations in homotypic or heterotypic supramolecular assemblies. [ABSTRACT FROM AUTHOR]

Herein, we report that assemblies of nucleopeptides selectively sequester ATP in complex conditions (for example, serum and cytosol). We developed assemblies of nucleopeptides that selectively sequester ATP over ADP. Counteracting enzymes interconvert ATP and ADP to modulate the nanostructures formed by the nucleopeptides and the nucleotides. The nucleopeptides, sequestering ATP effectively in cells, slow down efflux pumps in multidrug‐resistant cancer cells, thus boosting the efficacy of doxorubicin, an anticancer drug. Investigation of 11 nucleopeptides (including d‐ and l‐enantiomers) yields five more nucleopeptides that differentiate ATP and ADP through either precipitation or gelation. As the first example of assemblies of nucleopeptides that interact with ATP and disrupt intracellular ATP dynamics, this work illustrates the use of supramolecular assemblies to interact with small and essential biological molecules for controlling cell behavior. [ABSTRACT FROM AUTHOR]

Vancomycin (VCM) is clinically used in treating patients with postoperative intracranial infections. The cerebrospinal fluid (CSF) concentration of VCM varies greatly among patients. To guide the dosage regimens, monitoring of VCM in CSF is needed. However a method for analysis of VCM in human CSF is lacking. An ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was developed and validated for analysis of VCM in human CSF, and the agreement of UPLC-MS/MS and chemiluminescence immunoassay (CLIA) in the analysis of CSF VCM was evaluated. The ion transitions were m/z 725.5 > 144.1 for VCM and m/z 455.2 > 308.2 for methotrexate (internal standard). The agreement between UPLC-MS/MS and CLIA was evaluated by Bland-Altman plot in 179 samples. The calibration range of the UPLC-MS/MS method was 1-400 mg/L. The inaccuracy and imprecision were −0.69-10.80% and <4.95%. The internal standard normalized recovery and matrix factor were 86.14-99.31 and 85.84-92.07%, respectively. The measurements of CLIA and UPLC-MS/MS were strongly correlated ( r > 0.98). The 95% limit of agreement of the ratio of CLIA to UPLC-MS/MS was 61.66-107.40%. Further studies are warranted to confirm the results. [ABSTRACT FROM AUTHOR]

Abstract: Reaction‐diffusion (RD) is the most important inherent feature of living organisms, but it has yet to be used for developing biofunctional nanoparticles (NPs). Here we show the use of chirality to control the RD of NPs for selective inhibition of cancer cells. We observe that l‐phosphotyrosine ( l‐pY)‐decorated NPs (NP@ l‐pYs) are innocuous to cells, but d‐pY‐decorated ones (NP@ d‐pYs) selectively inhibit cancer cells. Our study shows that phosphatases, present in the culture and overexpressed on the cancer cells, dephosphorylate NP@ l‐pYs much faster than NP@ d‐pYs. Such a rate difference allows the NP@ d‐pYs to be mainly dephosphorylated on cell surface, and thus adhere selectively on the cancer cells, resulting in poly(ADP‐ribose)polymerase (PARP)‐hyperactivation‐mediated cell death. Without phosphate groups or with premature dephosphorylation before reaching cancer cells (as in the case of NP@ l‐pYs), the NPs are innocuous to cells. Moreover, NP@ d‐pYs exhibit even more potent activity than cisplatin for inhibiting platinum‐resistant ovarian cancer cells (e.g., A2780‐cis). As the first example of chirality controlling a RD process of NPs for inhibiting cancer cells, this work illustrates a fundamentally new way to develop nanomedicine based on RD processes and nanoparticles. [ABSTRACT FROM AUTHOR]

In this study, we report the design and synthesis of a silver nanowire-γ-Fe2O3 coaxial nanocable architecture (Ag NWs@γ-Fe2O3 nanocable) through mild oxidation of [Fe(CO)5] on the surface of silver nanowires followed by a calcination process. After optimization of the structural design, the Ag NWs@γ-Fe2O3 nanocable could deliver superior lithium storage performance in terms of high reversible capacity, good rate performance, and excellent stability, such as a high reversible capacity of about 890 mAhg-1 after 60 cycles at a current rate of 0.1 C (1.0 C=1005 mAg-1). The reversible capacity remains as high as about 550 mAhg-1 even at a high current rate of 2.0 C. This dramatic performance is mainly attributed to the smart coaxial design, which can not only alleviate the large volume change and prevent the aggregation of γ-Fe2O3 nanoparticles, but also enables good conductivity and thus enhances fast charge transfer. The unique structural features of the Ag NWs@γ- Fe2O3 nanocable represent a promising anode material in lithium-ion battery applications. [ABSTRACT FROM AUTHOR]

The development of highly efficient catalysts for the selective oxidation of styrene to benzaldehyde has attracted great attention in recent years because of its significance in synthetic chemistry. In this study, two different kinds of copper-based metal oxide nanoparticles (NPs), namely, CuO and CuO/Co3O4 NPs, were synthesized by a simple and scalable method, and these nanoparticles demonstrated efficient catalytic abilities for the selective oxidation of styrene and its derivatives to the corresponding aldehydes in the presence of tert-butyl hydroperoxide (TBHP) under mild reaction conditions in excellent yields. Importantly, both of the heterogeneous catalysts can be recycled up to five runs while still maintaining their high catalytic activity. [ABSTRACT FROM AUTHOR]

A little pressure for a lot of gain: An efficient method has been developed for the controlled hydrogenation of phenol using a platinum nanowire catalyst under mild conditions (>98.4 %, 1 atm H2, 60 °C). The catalyst also exhibited high levels of activity and selectivity towards other selected aromatic compounds bearing a variety of different substituents, demonstrating its generality towards the hydrogenation of aromatic compounds. [ABSTRACT FROM AUTHOR]

Over the wire and back again: The reversible hydrogenation–oxidative dehydrogenation of quinolines is reported by using Pt nanowire (NW) as the catalyst under mild reaction conditions. Pt NW shows high activity and selectivity in the hydrogenation of quinolines under H2 pressure (1 bar=100 kPa), and these hydrogenation products can be easily oxidized under the same conditions in an atmosphere of oxygen (1 bar) or in air. [ABSTRACT FROM AUTHOR]

Don′t get your nanowires crossed: Aluminum, as an attractive catalyst, has exhibited an effective doping behavior during silicon nanowire growth, in which Al can not only ensure a novel and efficient route to adjust Si nanowire compositions, but also plays a critical role in shaping the structural morphologies of Si nanowires. The fundamental understanding of the catalytic processes is crucial to the development of advanced silicon nanowire‐based devices. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Highly Efficient Synthesis of Azos Catalyzed by the Common Metal Copper (0) Through Oxidative Coupling Reactions" by J. He, C. Zhi, X. Li and others, published in the periodical "Science of Synthesis" in 2014.

An efficient and environmentally friendly method for copper(0)-catalyzed oxidation of benzylamines in the presence of 1 equiv. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to aromatic compounds complete hydrogenation with platinum nanowires under one bar pressure of hydrogen, published in the 2013 issue of the journal "ChemCatChem."