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Over the past few decades, biobased polylactic acid (PLA) has emerged as the most promising option to replace some of the fossil-based and nonbiodegradable polymers due to environmental concerns. In this study, a flexible polymer, polybutylene adipate terephthalate (PBAT) was blended with PLA to improve the toughness and flexibility of PLA, and the PLA/PBAT blend was further UV-induced to form crosslink structure. The results show that the flexibility and toughness of PLA could be significantly enhanced when PBAT was introduced, and the compatibility of PLA and PBAT could be enhanced by the development of a crosslink structure. Especially, the elongation at break and unnotched impact strength of ABT-UV30 (PLA/PBAT/triallyisocyanurate (TAIC) exposed to ultraviolet (UV) light for 30 min) was increased to 3.9 and 8.4 times of neat PLA. The glass transition temperature (Tg) of PLA was increased from 63.4 to 72.9 °C as the radiation duration was prolonged to 60 min. The melting point temperature of PBAT was also increased gradually until it eventually coincided with that of PLA. The thermalgravimetric analyzer thermograms show that a moderate amount of UV radiation can improve the thermal stability of the sample while an excessive amount of UV radiation can reduce the degradation temperature. [ABSTRACT FROM AUTHOR]

Purpose: Blind insertion limits the application of percutaneous peritoneal dialysis (PD) catheter placement. In this study, we first described the use of an optical puncture system in the PD catheter insertion, and investigated the feasibility and advantages of this modified technique. Methods: This retrospective study included 65 patients with chronic kidney disease stage 5 (CKD5) who received ultrasound-guided percutaneous PD catheter insertion with or without optical puncture system assistance between June 2018 and July 2019. The patients' characteristics as well as the surgical outcomes and complications were compared between the modified group and the routine percutaneous insertion group. Results: Twenty-five patients underwent optical puncture system assistant insertion, whereas 40 patients received routine percutaneous insertion. More patients had previous abdominal surgical histories in the modified group than those in the routine group (24.0% vs. 5.0%, p = 0.047). The time of accessing to the abdominal cavity was significantly shorter in the modified group (median [IQR]; 1.1 min [0.8–1.3] vs. 5.0 min [4.0–6.0]; p < 0.001). Meanwhile, the time of the whole procedure was also significantly shorter in the modified group (median [IQR]; 26.0 min [25.0–29.0] vs. 33.0 min [29.0–35.0]; p < 0.001). None of the patient in the modified group, while two patients (5.0%) in the routine group converted to open procedure. There were no significant differences in the short and long postoperative complications between the two groups. Conclusions: The operation of ultrasound-guided PD catheter placement with the optical puncture system is easy, safe, fast and accurate, whereby the PD catheter can be implanted percutaneously and visually under local anesthesia with minimal procedure-related complications. The visible puncture of the optical puncture system may facilitate ultrasound-guided percutaneous PD catheter insertion in patients with obesity and previous abdominal surgeries. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering (SERS) is gaining prominence as a rapid and effective detection method. However, this technique is still challenged by reusability and sampling issues, especially on irregular surfaces. To address these obstacles, a flexible SERS substrate is designed in this study by using reduced graphene oxide (rGO) as the active material and cotton fabric as the substrate material. The cotton fabric is first modified with a silicane coupling agent before coating with rGO to enhance the adhesion between the rGO and cotton fabric, which would allow reusability of the substrate. The resultant SERS substrate shows a better performance with an enhancement factor of 8 × 103 and a calculated sensitivity of 4.5 × 10−6 M, as well as excellent signal reproducibility with a relative standard deviation (RSD) of 4.72% and stability with RSD value of 5.47%. Meanwhile, the SERS substrate also demonstrates enhanced reusability, and retains strong Raman signals of the dye molecules even after 40 cycles of detection and washing process. The exceptional SERS performance, enhanced reusability, stability and signal reproducibility, along with other intrinsic advantages, such as low cost, ease of availability, and excellent flexibility, render the obtained SERS substrate in this study a promising product for detection in practical applications. [ABSTRACT FROM AUTHOR]