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The remotely controlled shape memory behaviors of a two-dimensional (2D) sheet to controlled helix structure upon external stimuli is of great significance in the field of smart materials. Herein, we devise a strategy to fabricate a series of shape memory polycaprolactone/[W.sub.18][O.sub.49] nanowire film via highly efficient UV-triggered thiol-acrylate click chemistry. The resultant polymer composites exhibited desirable photothermal transfer efficiency and can enable rapid temperature increase over the melting temperature of polymeric matrix, thus remotely actuating shape transformation within 8 s. Owing to the well- defined architecture of the polymer network, the fabricated elastic composite film exhibited a high degree of crystallinity and showed excellent shape memory properties with [R.sub.f] of 93.12% and [R.sub.r] of 95.32%. Remarkably, under a 160 mW/[cm.sup.2] simulated sunlight illumination, the transformation of flat 2D film into 3D chiral actuators is driven by designing anisotropic bilayer thin sheet, and it yields right- and left-handed helix. This work will pave the way for designing biomimetic flexible actuators toward multifunctional shape-shifting devices. Highlights * Shape memory polycaprolactone/[W.sub.18][O.sub.49] nanowires composite film is fabricated via UV-triggered thiol-ene click chemistry. * Polymer composites exhibit light-activated shape memory behaviors. * The composite films show excellent shape fixity and shape recovery ratio based on the well-defined network. * The shape morphing behaviors of a flexible 2D bilayer strip into 3D chiral actuators are achieved. KEYWORDS flexible actuators, polycaprolactone, shape memory polymers, stimuli- responsive polymers, 1 | INTRODUCTION Stimuli-responsive morphing materials belong to one kind of molecules with 'intelligent' behavior, which can generate corresponding response signals upon the stimuli of heat, light, electric field, etc. [...]

In order to obtain the novel poly(ε-caprolactone) (PCL) cross-linked networks with good shape memory properties, the cross-linked networks of PCL with different molecular weights were prepared by thiol-ene click chemistry method, and its microstructure, thermal properties, mechanical properties and shape memory properties were characterized. The results show that the hydroxyl end of PCL was successfully converted to acrylate-terminated PCL, and almost all the samples show perfect cross-linked network, and the cross-linked polymer has a thermally induced shape memory effect; with the increase of the molecular weight of PCL diol, the melting temperature and crystallinity of the cross-linked network also show an upward trend; the molecular weight of PCL diol has a certain influence on its fixation ability, but regardless of the length of PCL diol, the shape recovery rate of all samples can reach more than 90%. The efficient thiol-ene click chemistry reaction ensures the uniform distribution of PCL chains between cross-linked nodes, the cross-linked network has good network structure, good mechanical and shape memory properties. The exploration of new PCL cross-linked network provides a feasible way for the end functionalization of polymers.

Organic luminophores with high emission efficiency in solution as well as solid‐state have received increasing attention due to their promising applications in biosensors, biological imaging, and optoelectronic devices. Herein, four triphenylamine (TPA)‐substituted boron ketoimine molecules (TPA‐BKI a‐d) are designed and synthesized by combining a donor‐acceptor (D‐A) electronic system and highly twisted block. The asymmetry of molecular and the planarity of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) sides in the excited state endow TPA‐BKI a‐d with rigidified conformations, allowing bright emission in dilute solution. Additionally, their highly twisted structures avoid close contact between molecules and detrimental exciton interactions, leading to efficient emission in the solid state. Meanwhile, the emission colors are modulated by the incorporation of different substituents through the amino‐yne click reaction. Furthermore, because of the protonation and deprotonation of the amino substituents, TPA‐BKI‐d exhibits reversible alterations of optical properties in both solution and solid states. [ABSTRACT FROM AUTHOR]

The spatially controllable shape-shifting behaviors of a planar two-dimensional (2D) film to three-dimensional (3D) shapes upon external stimuli are of paramount significance for the development of smart materials. Herein, the present work focuses on fabricating plain film whose shape can be remotely and spatially transformed into various 3D configurations via the formation of a laser-induced temperature gradient; when subjected to laser irradiation, the prestretched hybrid films exhibit out-of-plane bending behavior owing to anisotropic chain relaxation and strain energy release. On this basis, various sophisticated shape transformations can be achieved by site-specific irradiations of laser with a controllable magnitude. Meanwhile, shape morphing involving reversible bending transformations can also be realized by employing the laser on the corresponding opposite side of the hybrid films. Remarkably, under a 160 mW/cm2 simulated sunlight illumination, the transformation of flat 2D film into 3D chiral actuators is driven by material anisotropy and geometrical heterogeneity of a bilayer strip design, and it yields right and left-handed helix, the morphologies of the helix shape can be precisely tailored by the strip angles and strain values. [ABSTRACT FROM AUTHOR]

Three‐arm star polymethacrylates with dual‐phase (solution and solid‐state) fluorescent emission have been synthesized via atom transfer radical polymerization (ATRP) using a triphenylamine‐derived organboron complex (TAPA‐BKI‐3Br) as initiator. The as‐synthesized three‐arm star polymethacrylates exhibited bright emission in both solution and the solid states due to the highly twisted structure and intramolecular charge transfer (ICT) effect of TAPA‐BKI core, as well as the steric effect and restriction of intramolecular motions from the polymer arms. And the polymer chains have an important influence on the photophysical behavior of the as‐synthesized three‐arm star polymethacrylates in the aggregated state. [ABSTRACT FROM AUTHOR]

To realize the biocompatibility, mechanical strength, and sustained antibacterial properties of medical materials, it is feasible to introduce antibacterial material components into biomass matrix to prepare medical materials. Herein, zinc oxide (ZnO) was in-situ synthesized in bacterial cellulose (BC) dispersion and filtered into a film, and the BC/ZnO composite film was further immersed in sodium alginate (Alg) solution to construct the second layer structure. The microstructure, mechanical strength, and antibacterial properties of the composite films were investigated systematically. The tensile strength of the BC/ZnO/CAlg sample was achieved at 16.5 ± 2.4 MPa, much higher than that of the Zn2+ crosslinked CAlg film of 11.5 ± 1.2 MPa. The Zn2+ cross-linked Alg in the outer layer and the BC/ZnO composite film in the inner layer combined to create a synergistic effect. This secondary structure design ensures good hydrophilicity and hygroscopicity of the material which enables the sustained-release migration of Zn2+ from the inner layer to the outer layer. Finally, the BC/ZnO/CAlg composite film possesses excellent antibacterial performance against Staphylococcus aureus and Escherichia coli. In addition, this work systematically expounds on the antibacterial and slow-release mechanism of secondary structure composite membranes. The results will provide a database and theoretical reference for applying BC/ZnO/CAlg composite membranes in the medical field. [ABSTRACT FROM AUTHOR]

It is crucial to enhance the mechanical properties to realize the application of sodium alginate (Alg) in engineering materials. Herein, a Ca2+ cross-linked sodium alginate/graphene oxide (CAlg/GO) composite fiber with a secondary reinforcement structure was prepared via wet spinning. The microstructure and physical properties of the fibers were characterized by scanning electron microscopy, infrared spectroscopy, X-ray diffraction, and mechanical strength testing. The composite fiber's strength and toughness improved significantly, benefiting from the uniform distribution of GO in the Alg matrix together with the simultaneous cross-linking of Ca2+ to Alg and GO sheets. Accompanying the addition of GO reaching 15%, the strength increased by 184 ± 16%. Meanwhile, the CAlg/GO composite fiber possessed a significant improvement in flame retardancy; the limiting oxygen index increased from 33 to 37 after adding 10% GO sheets to the fiber. In addition, the composite fiber's reinforcement, toughening, and flame retarding mechanisms were discussed from the point of the interaction between Alg, GO, and Ca2+, as this study will provide data and theoretical reference for the application of high-performance CAlg/GO composite fiber. [ABSTRACT FROM AUTHOR]

Background: Currently there is no standard therapy recommended for second‐line treatment for thymic carcinoma. Our study compared multidrug chemotherapy, single‐agent chemotherapy, and PD‐1 inhibitors in patients diagnosed with advanced thymic carcinoma who had previous platinum‐based chemotherapy at the clinic. Methods: The study included patients with thymic carcinoma who failed first‐line platinum‐based chemotherapy. Kaplan–Meier methods were applied in the study for estimating the progression‐free survival (PFS) and overall survival (OS) curves. Pearson chi‐square or Fisher's exact chi‐square test was adopted to make comparisons of the objective response rate (ORR) between treatment groups. Cox regression was used for the multivariate analyses in PFS and OS. Results: Among the 92 patients enrolled, multidrug chemotherapy was used in 51 (55.4%) patients for second‐line therapy. Thirty‐six patients (35.9%) received single‐agent chemotherapy, and eight patients (8.7%) underwent PD‐1 inhibitors. The multidrug chemotherapy group showed better efficacy than the other two groups, with an ORR of 35.3% (p = 0.006). The median PFS of multidrug chemotherapy, single‐agent chemotherapy and PD‐1 inhibitors were 5.0 months, 3.0 months, and 4.0 months, respectively (p = 0.008). Patients in the multidrug chemotherapy group also showed an advantage in OS in comparison with the other two treatment groups (p = 0.045), with a median OS of 30.4 months. Multivariate analysis showed that second‐line treatment was independent factor for both PFS (p = 0.035) and OS (p = 0.037). Grade 3–4 AEs were mostly detected in patients receiving multidrug chemotherapy and were primarily hematologic. Treatment‐related mortality was not found in any of the groups. Conclusions: Multidrug chemotherapy had a trend toward a more positive response rate and outcomes in longer survival time than single‐agent chemotherapy and PD‐1 inhibitors. Multidrug chemotherapy is a choice worth considering for second‐line therapy in patients with thymic carcinoma if tolerable. [ABSTRACT FROM AUTHOR]

Objective: Pembrolizumab and bevacizumab both have antitumor activity. According to NCCN updated guideline the benefit of pembrolizumab or bevacizumab as a first line in management of advanced nonsmall cell lung cancer (NSCLC) is documented in randomized controlled studies. The study aimed to evaluate the response and complications of patients with advanced NSCLC treated with pembrolizumab or bevacizumab plus chemotherapy. Methods: This study was a retrospective cohort study of patients with advanced nonsquamous NSCLC who received cisplatin with pemetrexed combined with pembrolizumab (A group) or bevacizumab (B group) from 07/02/2018 to 07/03/2021 at Peking University Cancer Hospital. Progression-free survival (PFS) was the primary outcome. The secondary outcomes included overall survival (OS), objective response rate (ORR), disease control rate (DCR), duration of response (DoR), and adverse events (AEs). Results: This study included 66 patients, 34 in A group and 32 in B group. There were no differences in median PFS (7.6 vs 9.9 months, P =.601). There were no differences in median OS (23.1 vs 24.2 months, P =.782). There were no differences in ORR (57.6 % vs 41.9 %, P =.211) and DCR (93.9 % vs 100.0 %, P =.164) between 2 groups. The occurrence of AEs was similar. No new safety signals were observed. Grade 3 to 4 treatment-related AEs occurred in 17 (50.0 %) patients of A group and in 12 (37.5 %) of B group (P >.05). Conclusion: The addition of pembrolizumab or bevacizumab to pemetrexed plus cisplatin was well tolerated and resulted in a clinically meaningful treatment benefit in advanced nonsquamous NSCLC. When pembrolizumab is not suitable, bevacizumab plus chemotherapy may be an option. [ABSTRACT FROM AUTHOR]

Three-arm star polymethacrylates with dual-phase (solution and solid-state) fluorescent emission have been synthesized via atom transfer radical polymerization (ATRP) using a triphenylamine-derived organboron complex (TAPA-BKI-3Br) as initiator. The as-synthesized three-arm star polymethacrylates exhibited bright emission in both solution and the solid states due to the highly twisted structure and intramolecular charge transfer (ICT) effect of TAPA-BKI core, as well as the steric effect and restriction of intramolecular motions from the polymer arms. And the polymer chains have an important influence on the photophysical behavior of the as-synthesized three-arm star polymethacrylates in the aggregated state., (© 2023 Wiley-VCH GmbH.)

Background: Anaplastic lymphoma kinase ( ALK ) gene rearrangement is a series of mutations of non-small cell lung cancer (NSCLC) patients. Since 2011, multiple ALK inhibitors (ALKis) have been developed and launched for targeted therapy. In this study, we sought to investigate different strategies of sequential applying the ALKis and their clinical benefits to the overall survival (OS)., Methods: A total of 176 patients with advanced NSCLC (stage IIIB-IV) harboring the ALK rearrangement were included in this cohort study. They were diagnosed between February 1, 2012 and November 19, 2019 at Peking University Cancer Hospital. Clinical characters were reviewed from patients' records. Strategies of drugs, progression-free survival (PFS) and OS were collected during the follow-ups. The Kaplan-Meier method and multivariate Cox proportional-hazard analysis were used to conduct the analyses survival and to examine the relationship between the variables and OS., Results: A significantly longer OS was observed either in patients treated with crizotinib [N=106, median OS (mOS): 32.9 months] or in patients treated with a next-generation ALKi [N=34, mOS: not reached (NR)] as the initial ALKi, compared with patients treated with conventional chemotherapy but no ALKi (N=36, mOS: 10.3 months, P<0.001). After disease progression with initial crizotinib, patients who received no ALKi had shorter OS than those who received only crizotinib beyond progressive disease (CBPD) (mOS: 9.7 vs. 20.3 months; P=0.015), only subsequent next-generation ALKis (mOS: 9.7 vs. 41.1 months; P<0.001), and CBPD followed with subsequent next-generation ALKis (mOS: 9.7 months vs. NR; P<0.001). Patients treated with 2 types of ALKi had better survival than those treated with 1 ALKi (mOS: 45.8 vs. 21.3 months, P=0.003), but no such survival benefit was observed in patients treated with ≥3 ALKis (P=0.366)., Conclusions: ALKis have been shown to be clinically effective in treating NSCLC patients with ALK rearrangements. In the case of disease progression with crizotinib, either of CBPD or sequential other ALKis can extend patients' OS. The sequential application of multiple ALKis was found to be better than it of single ALKi in prolonging OS. However, the question of which inhibitor to select as the initial inhibitor needs to be examined further in future studies., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-22-622/coif). The authors have no conflicts of interest to declare., (2022 Journal of Thoracic Disease. All rights reserved.)

Lakes are important methane (CH 4 ) sources to the atmosphere, especially eutrophic lakes with cyanobacterial blooms accompanied by volatile sulfur compound (VSC) emissions. CH 4 oxidation is a key strategy to mitigate CH 4 emission from lakes. In this study, we characterized the fate of CH 4 -derived carbon and active microbial communities in lake sediments with CS 2 used as a typical VSC, based on the investigation of CH 4 and VSC fluxes from Meiliang Bay in Lake Taihu. Stable isotope probing microcosm incubation showed that the efficiency of CH 4 -derived carbon incorporated into organic matter was 21.1% in the sediment with CS 2 existence, which was lower than that without CS 2 (27.3%). SO 4 2- -S was the main product of CS 2 oxidation under aerobic condition, accounting for 59.3-62.7% of the input CS 2 -S. CS 2 and CH 4 coexistence led to a decrease of methanotroph and methylotroph abundances and stimulated the production of extracellular polymeric substances. CS 2 and its metabolites including total sulfur, SO 4 2- and acid volatile sulfur acted as the main drivers influencing the active microbial community structure in the sediments. Compared with α-proteobacteria methanotrophs, γ-proteobacteria methanotrophs Methylomicrobium, Methylomonas, Crenothrix and Methylosarcina were more dominant in the sediments. CH 4 -derived carbon mainly flowed into methylotrophs in the first stage. With CH 4 consumption, more CH 4 -derived carbon flowed into non-methylotrophs. CS 2 could prompt more CH 4 -derived carbon flowing into non-methanotrophs and non-methylotrophs, such as sulfur-metabolizing bacteria. These findings can help elucidate the influence of VSCs on microorganisms and provide insights to carbon fluxes from eutrophic lake systems., (Copyright © 2022 Elsevier Inc. All rights reserved.)