A series of crystalline shape memory polyurethanes (SMPUs) were synthesized from polycaprolactone diols and 4,4 -methylenedicyclohexyl diisocyanate (H 12 MDI) with chemical incorporation of allyl isocyanate modified graphene oxide (iGO) into the PU. Actuation of hybrid SMPUs by infrared (IR) absorption of iGO as well as the direct heat actuated SMPUs has been studied in terms of the isothermal crystallization rate, near-IR absorption, and thermal, mechanical, and shape memory properties. It was found that iGO functions as a multifunctional cross-linker at low contents and a nucleating agent at high contents, and as a reinforcing filler, while light absorption by the iGO induced melting of the PU soft segment, giving rise to a shape recovery of over 90% at 1% iGO (G10).

An investigation has been performed into the effect of the die and deformation pattern on twist-assisted upset forging. Rotation of the lower flat die accompanied by axial compression of the punch plays a distinct role in saving axial force. In this study, an upper bound analysis considering bulge formation, finite element method simulations (DEFORM 3D) and experimental research were carried out. A simple kinematically admissible velocity field for three-dimensional deformation is presented for twist-assisted upset forging of a cylindrical billet. An analytical expression for the upset force and torque is obtained from several process parameters. An increase in the friction factor and rotation speed was found to favour decreases in the magnitude of the upset force, dead metal zone and non-homogeneous deformation. Plasticine model experiments were performed where the lower die was rotated against the workpiece using a 5 ton model press.

Background Proactive dosing based on drug monitoring of adalimumab has been reported to be associated with higher rates of clinical remission in children with Crohn’s disease (CD). We aimed to investigate whether proactive drug monitoring of infliximab (IFX) is associated with higher rates of endoscopic healing (EH) in paediatric patients with CD. Methods We conducted a nonblinded, randomized controlled trial of 112 children with CD who were biologic naïve and had responded to induction treatment with IFX at 4 centers in South Korea from July 2017 to November 2020. Patients were randomly assigned to groups that received dosing based on proactive monitoring or clinically based dosing. The primary endpoint was EH at 1 year treatment. Results The primary endpoint was achieved in 80.0% (40/50) of the proactive dosing group and 57.1% (28/49) of the clinically based dosing group (P = 0.025). Transmural healing was achieved in 37.8% (17/45) of the proactive dosing group and 30.8% (12/39) of the clinically based dosing group (P = 0.657). Sustained corticosteroid-free clinical remission was achieved in 89.5% (51/57) of the proactive dosing group and 70.9% (39/55) of the clinically based dosing group (P = 0.025). Sustained durability of infliximab was observed in 94.7% (54/57) of the proactive dosing group and 92.7% (51/55) of the clinically based dosing group (P = 0.714). Conclusion Dosing based on proactive monitoring was superior to clinically based dosing in terms of endoscopic healing in a randomized controlled trial of paediatric CD.

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