High performance piezoelectric devices based on arrays of PVDF-TrFE nanofibers have been introduced in the literature for a variety of applications including energy harvesting and sensing. In this Research Article, we utilize uniaxial tensile test on arrays of nanofibers, microtensile, and nanoindentation and piezo-response force microscopy (PFM) on individual nanofibers, as wells as DSC, XRD, and FTIR spectroscopy to investigate the effect of annealing on microstructure, mechanical, and piezoelectric properties of arrays and individual electrospun nanofibers. For PVDF-TrFE nanofibers annealing in a temperature between the Curie and melting temperature (in paraelectric phase) results in ∼70% increase in crystallinity of the nanofibers. The findings of our multiscale experiments reveal that this improvement in crystallinity results in ∼3-fold increase in elastic modulus, and ∼55% improvement in piezoelectric constant. Meanwhile, the ductility and tensile toughness of the nanofibers drop by ∼1 order of magnitude. In addition, nanoscale cracks were observed on the surface of the annealed nanofibers; however, they did not result in significant change in the strength of the nanofibers. The results of this work may have important implications for applications of PVDF-TrFE in energy harvesting, biomedical, and sensor areas.

Background: Although lateral ligament augmentation using suture-tape has been effective for restoration of mechanical ankle stability, few data are available regarding changes of peroneal strength, proprioception, and postural control. The aim of this study was to determine effects of suture-tape augmentation on functional ankle instability (FAI). Methods: Twenty-four patients who underwent suture-tape augmentation were eligible and were followed more than 2 years postoperatively. Functional outcomes were evaluated with the Cumberland Ankle Instability Tool (CAIT), Foot and Ankle Ability Measure (FAAM). Changes of peroneal strength, proprioception and postural control were analyzed with an isokinetic dynamometer and a modified Romberg test. Results: CAIT and FAAM (average of daily and sports activity scores) significantly improved to average 27.2 points and 86.7 points, respectively, at final follow-up. Peak torque for eversion in 60 degrees/s angular velocity significantly improved to 10.6 Nm at final follow-up. Deficit ratio of peak torque for eversion significantly improved from mean 39.5% to 20.9%, and significant side-to-side difference was revealed ( P < .001). There were no significant differences in joint position sense. A significant improvement in balance retention time was revealed at final follow-up, and the relative deficit ratio compared to the unaffected side was 30.9%. Conclusions: Patient-reported functional outcomes significantly improved after lateral ligament augmentation using suture-tape. Although this procedure demonstrated significant effects on FAI based on improvement of isokinetic peroneal strength and postural control, recovery rates compared to the unaffected side were not significant at the intermediate-term follow-up. In addition, there was no positive effect on proprioception of the ankle. Level of Evidence: Level IV, prospective case series.

Metal–organic frameworks (MOFs), which are porous inorganic–organic hybrid materials, act as versatile catalyst platforms for various organic transformations. In particular, the aerobic oxidation of alcohols to the corresponding aldehydes (or ketones) has been extensively studied using various MOFs and their analogs. In this account, we summarize the performance of MOF‐based catalysts for the aerobic oxidation of alcohols based on the position of the catalytic species and the type of functionalization. Moreover, recent advances in MOF‐based catalysts for aerobic oxidation are discussed in terms of catalytic efficiency and substrate size discrimination.

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The supracondylar process is a beak-shaped bony process on the anteromedial aspect of the distal humerus. The ligament of Struthers is a fibrous band extending from the tip of the process to the medial epicondyle. The median nerve and brachial artery pass under the ligament of Struthers and consequently can be compressed, causing supracondylar process syndrome. As a rare cause of proximal median nerve entrapment, supracondylar process syndrome is triggered when the median nerve is located in the superficial or deep layer of the ligament of Struthers as a result of anatomical variation. The supracondylar process can be easily detected on X-ray images obtained in oblique views but may not be identified in only anteroposterior or lateral views. In this article, we present 2 cases of supracondylar process syndrome and describe the process of diagnosis and treatment and results of a literature review.