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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]