10 research outputs found
The Fabrication and Characterization of Piezoelectric PZT/PVDF Electrospun Nanofiber Composites
Piezoelectric nanofiber composites of polyvinylidene fluoride (PVDF) polymer and PZT (Pb(Zr0.53Ti0.47)O3) ceramics were fabricated by electrospinning. The micro‐ structure of the PZT/PVDF electrospun nanofiber compo‐ sites was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The tensile properties (stress- strain curves) and electrical properties (P-E hysteresis loops) of the PZT/PVDF electrospun nanofiber composites were investigated as a function of PZT content from 0 wt% to 30 wt%. The results demonstrated that a PZT content of 20 wt % had enhanced tensile and piezoelectric characteristics
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A fabric-based wearable sensor for continuous monitoring of decubitus ulcer of subjects lying on a bed.
For multifunctional wearable sensing systems, problems related to wireless and continuous communication and soft, noninvasive, and disposable functionality issues should be solved for precise physiological signal detection. To measure the critical transitions of pressure, temperature, and skin impedance when continuous pressure is applied on skin and tissue, we developed a sensor for decubitus ulcers using conventional analog circuitry for wireless and continuous communication in a disposable, breathable fabric-based multifunctional sensing system capable of conformal contact. By integrating the designed wireless communication module into a multifunctional sensor, we obtained sensing data that were sent sequentially and continuously to a customized mobile phone app. With a small-sized and lightweight module, our sensing system operated over 24 h with a coin-cell battery consuming minimum energy for intermittent sensing and transmission. We conducted a pilot test on healthy subjects to evaluate the adequate wireless operation of the multifunctional sensing system when applied to the body. By solving the aforementioned practical problems, including those related to wireless and continuous communication and soft, noninvasive, and disposable functionality issues, our fabric-based multifunctional decubitus ulcer sensor successfully measured applied pressure, skin temperature, and electrical skin impedance
Predicting factor analysis of postoperative complications after robot-assisted radical cystectomy: Multicenter KORARC database study
© 2022 The Japanese Urological Association.Objectives: To evaluate postoperative complications following robot-assisted radical cystectomy in patients diagnosed with bladder cancer and reveal if there are predictors for postoperative complications. Methods: Prospectively collected medical records of 730 robot-assisted radical cystectomy patients between 2007/04 and 2019/05 in 13 tertiary referral centers were reviewed. Perioperative outcomes were compared between two groups by postoperative complications (complication vs non-complication). We assessed recurrence-free survival, cancer-specific survival, and overall survival between groups. Regression analyses were implemented to identify factors associated with postoperative complications. Results: Any total and high-grade complication (Clavien–Dindo grade ≥3) rates were 57.8% and 21.1%, respectively. Patients in complication group had significantly higher proportion of diabetes mellitus (P = 0.048), chronic kidney disease (P = 0.011), dyslipidemia (P < 0.001), longer operation time (P = 0.001), more estimated blood loss (P = 0.001), and larger intraoperative fluid volume (P < 0.001). There was a significant difference in cancer-specific survival (log-rank P = 0.038, median cancer-specific survival: both groups not reached). Dyslipidemia (odds ratio 2.59, P = 0.002) and intraoperative fluid volume (odds ratio 1.0002, P = 0.040) were significantly associated with high-grade postoperative complications. Diabetes mellitus (odds ratio 1.97, P = 0.028), chronic kidney disease (odds ratio 1.89, P = 0.046), dyslipidemia (odds ratio 5.94, P = 0.007), and intraoperative fluid volume (odds ratio 1.0002, P = 0.009) were significantly associated with any postoperative complications. Conclusions: Patients with diabetes mellitus, chronic kidney disease, dyslipidemia, or a relatively large intraoperatively infused fluid volume are more likely to develop postoperative complications. Patients with postoperative complications might have a possibility of lower cancer-specific survival rate.N
Preoperative smoking and robot-assisted radical cystectomy outcomes & complications in multicenter KORARC database
Abstract To investigate the influence of preoperative smoking history on the survival outcomes and complications in a cohort from a large multicenter database. Many patients who undergo radical cystectomy (RC) have a history of smoking; however, the direct association between preoperative smoking history and survival outcomes and complications in patients with muscle-invasive bladder cancer (MIBC) who undergo robot-assisted radical cystectomy (RARC) remains unexplored. We conducted a retrospective analysis using data from 749 patients in the Korean Robot-Assisted Radical Cystectomy Study Group (KORARC) database, with an average follow-up duration of 30.8 months. The cohort was divided into two groups: smokers (n = 351) and non-smokers (n = 398). Propensity score matching was employed to address differences in sample size and baseline demographics between the two groups (n = 274, each). Comparative analyses included assessments of oncological outcomes and complications. After matching, smoking did not significantly affect the overall complication rate (p = 0.121). Preoperative smoking did not significantly increase the occurrence of complications based on complication type (p = 0.322), nor did it increase the readmission rate (p = 0.076). There were no perioperative death in either group. Furthermore, preoperative smoking history showed no significant impact on overall survival (OS) [hazard ratio (HR) = 0.87, interquartile range (IQR): 0.54–1.42; p = 0.589] and recurrence-free survival (RFS) (HR = 1.12, IQR: 0.83–1.53; p = 0.458) following RARC for MIBC. The extent of preoperative smoking (≤ 10, 10–30, and ≥ 30 pack-years) had no significant influence on OS and RFS in any of the categories (all p > 0.05). Preoperative smoking history did not significantly affect OS, RFS, or complications in patients with MIBC undergoing RARC