Synthesis and Characterization of Polysulfone (PSU)/Philippine Halloysite (PH-HAL) Nanostructured Membrane via Electrospinning

Membrane technology is widely used in many separation processes because of its multi-disciplinary characteristics. One of the techniques that is used in the fabrication of membranes is the electrospinning process which can create nanofibers from a very wide range of polymeric materials. In this study, electrospun nanostructured fibrous composite membranes of polysulfone (PSU), commercial halloysite (COM-HAL), and Philippine halloysite (PH-HAL) were synthesized. The concentrations of COM-HAL and PH-HAL were both varied from 0.5%, 1%, and 2%. The FTIR results showed that there were changes in the intensity of the PSU-IR spectra which confirmed the presence of COM-HAL and PH-HAL in the synthesized membranes. The SEM revealed that nanofibers can be successfully produced by the addition of LiCl salt in PSU with varying HAL concentrations. Also, it was observed that the addition of HAL with varying concentrations have no significant effect on wettability due to the strong hydrophobic character of the PSU membrane. Moreover, it was found from the analysis of mechanical properties that the tensile strength of the membranes weakened by the addition of HAL due to its weak interaction with PSU

Synthesis and Characterization of Polysulfone (PSU)/Philippine Halloysite (PH-HAL) Nanostructured Membrane via Electrospinning

Membrane technology is widely used in many separation processes because of its multi-disciplinary characteristics. One of the techniques that is used in the fabrication of membranes is the electrospinning process which can create nanofibers from a very wide range of polymeric materials. In this study, electrospun nanostructured fibrous composite membranes of polysulfone (PSU), commercial halloysite (COM-HAL), and Philippine halloysite (PH-HAL) were synthesized. The concentrations of COM-HAL and PH-HAL were both varied from 0.5%, 1%, and 2%. The FTIR results showed that there were changes in the intensity of the PSU-IR spectra which confirmed the presence of COM-HAL and PH-HAL in the synthesized membranes. The SEM revealed that nanofibers can be successfully produced by the addition of LiCl salt in PSU with varying HAL concentrations. Also, it was observed that the addition of HAL with varying concentrations have no significant effect on wettability due to the strong hydrophobic character of the PSU membrane. Moreover, it was found from the analysis of mechanical properties that the tensile strength of the membranes weakened by the addition of HAL due to its weak interaction with PSU

Rate Control versus Rhythm Control for Atrial Fibrillation after Cardiac Surgery

BACKGROUND Atrial fibrillation after cardiac surgery is associated with increased rates of death, complications, and hospitalizations. In patients with postoperative atrial fibrillation who are in stable condition, the best initial treatment strategy -heart-rate control or rhythm control -remains controversial. METHODS Patients with new-onset postoperative atrial fibrillation were randomly assigned to undergo either rate control or rhythm control. The primary end point was the total number of days of hospitalization within 60 days after randomization, as assessed by the Wilcoxon rank-sum test. RESULTS Postoperative atrial fibrillation occurred in 695 of the 2109 patients (33.0%) who were enrolled preoperatively; of these patients, 523 underwent randomization. The total numbers of hospital days in the rate-control group and the rhythm-control group were similar (median, 5.1 days and 5.0 days, respectively; P = 0.76). There were no significant between-group differences in the rates of death (P = 0.64) or overall serious adverse events (24.8 per 100 patient-months in the rate-control group and 26.4 per 100 patient-months in the rhythm-control group, P = 0.61), including thromboembolic and bleeding events. About 25% of the patients in each group deviated from the assigned therapy, mainly because of drug ineffectiveness (in the rate-control group) or amiodarone side effects or adverse drug reactions (in the rhythm-control group). At 60 days, 93.8% of the patients in the rate-control group and 97.9% of those in the rhythm-control group had had a stable heart rhythm without atrial fibrillation for the previous 30 days (P = 0.02), and 84.2% and 86.9%, respectively, had been free from atrial fibrillation from discharge to 60 days (P = 0.41). CONCLUSIONS Strategies for rate control and rhythm control to treat postoperative atrial fibrillation were associated with equal numbers of days of hospitalization, similar complication rates, and similarly low rates of persistent atrial fibrillation 60 days after onset. Neither treatment strategy showed a net clinical advantage over the other