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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.

Objective To explore the impact of venous thromboembolism (VTE) on the diagnosis and treatment of lung cancer patients. Methods We retrospectively analyzed the clinical data of lung cancer patients with VTE treated in Peking University Cancer Hospital. The incidence of VTE was calculated and the relation between VTE and lung cancer was analyzed. Results Among 1766 patients with lung cancer, VTE occurred in 115(6.5%) patients. Among 115 VTE cases, there were 78(67.8%) males patients; 82(71.3%) cases were deep venous thrombosis, 21(18.3%) cases were pulmonary embolism, 12(10.4%) cases were deep venous thrombosis with pulmonary embolism; 74(64.3%) cases were symptomatic VTE; 102(88.7%) patients received antithrombotic therapy. Among the patients who received antithrombotic therapy, 97(95.1%) cases chose drug therapy. In drug treatment, 65(67.0%) cases used adequate/standard dose. Among 115 VTE cases, 52(45.2%) patients had improvement or disappearance of thrombus, 32(27.8%) patients had no improvement, and 31(27.0%) patients with unknown results; 11(9.6%) patients had adverse reactions such as bleeding during antithrombotic therapy; 30(26.1%) patients changed antineoplastic treatment plan due to VTE. Conclusion VTE is a common complication of lung cancer patients. Antithrombotic therapy for lung cancer patients with VTE is complex, the treatment effect is not ideal and the risk of adverse reactions such as bleeding is high. VTE has a great impact on the implementation of anti-cancer treatment.

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]