New insight into the fouling behavior of hydrophobic and hydrophilic polypropylene membranes in integrated membrane bioreactors.

To investigate the effect of hydrophobic and hydrophilic polypropylene hollow fiber membranes (PPHFMs) applied in membrane bioreactors (MBR), the fouling behaviors of membrane surfaces and pores have been tested. The structural and morphological features on the membrane surface were characterized using attenuated total reflection-Fourier transform infrared spectroscopy, field emission scanning electron microscopy, atomic force microscope, energy dispersive X-ray spectroscopy and laser granularity distribution analysis. The results showed that significantly more polysaccharide, protein and inorganic ingredients were accumulated in the original membrane compared to the hydrophilic membrane. Furthermore, it was found that the pore size influenced the particle distribution and accumulation, such that smaller pore size membranes tended to contain fewer pollutants and a narrow size distribution. Under a constant flux of 11.5 L/m2 h, the transmembrane pressure (TMP) varied narrowly between 38 and 53 KPa. Alongside this, a relatively hydrophilic membrane (PP-g-AA) showed the characteristics of lower TMP in comparison to hydrophobic membranes (PP). Indeed, the flux recovery was 30% higher than those of the original PPHFM. This investigation broadens our understanding of membrane modifying and fouling behavior in integrated MBRs.

Validation of the G.LAB MD2680 digital automatic blood pressure monitor according to international protocols.

OBJECTIVE: The aim of this study was to validate the G.LAB MD2680 digital automatic blood pressure (BP) monitor according to major international protocols. PARTICIPANTS AND METHODS: The device was evaluated against auscultatory sphygmomanometry according to the European Society of Hypertension International Protocol (ESH-IP) revision 2010, the British Hypertension Society (BHS), and the International Organization for Standardization (ISO) 81060-2:2013 protocols. Bland-Altman plots were completed for systolic (SBP) and diastolic blood pressures (DBP), and the mean differences and SDs between the test device and the reference device were computed for all BP values. RESULTS: The G.LAB MD2680 passed the ESH-IP revision 2010 on 33 participants with a mean device-observer difference of 0.89±4.97 mmHg for SBP and 0.72±4.91 mmHg for DBP, respectively. The device achieved A/A grading for the BHS protocol among 85 participants with a device-observer difference of 0.70±6.35 mmHg for SBP and 0.62±6.41 mmHg for DBP, respectively. Furthermore, it also fulfilled the two criteria of the ISO 81060-2:2013 protocol. CONCLUSION: The G.LAB MD2680 digital automatic BP monitor fulfilled the accuracy requirements of the ESH-IP revision 2010 and the ISO 81060-2:2013 protocols, and achieved A/A grade of the BHS protocol, and it can be recommended for self-measurement in adults.

Some subtypes of endocannabinoid/endovanilloid receptors mediate docosahexaenoic acid-induced enhanced spatial memory in rats.

ω-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) enhances cognitive functions; however, the underlying molecular mechanism remains unclear. Compelling evidence suggests that the endocannabinoid/endovanilloid systems play a pivotal role in regulating cognitive function. Thus, to correlate the effect of DHA on cognitive performance with the expression of endocannabinoid and endovanilloid receptors, we supplemented the diet of rats with DHA and performed in vitro experiments that focused on the endocannabinoid/endovanilloid receptors. We found that in vivo supplementation with an appropriate dose of DHA (150 or 300mg/kg/d) significantly improved learning and memory but that a higher intake (600mg/kg/d) increased the risk of memory impairment. In addition, we found that some subtypes of endocannabinoid/endovanilloid receptors (cannabinoid [CB] and transient receptor potential vanilloid [TRPV] receptors) were regulated in vitro by different concentrations of DHA in primary hippocampal neuron culture medium. Real-time polymerase chain reaction and western blot analysis showed that expression of both CB1 and TRPV1 was upregulated in a dose-dependent manner and reached a maximum level at 30µmol/L (CB1) and 60µmol/L (TRPV1) DHA. However, TRPV2 expression was downregulated in a dose-dependent fashion, and the peak of TRPV2 suppression was observed at 60µmol/L. The dose-dependent effects of DHA on the expression of these receptors were well correlated with DHA's effect on spatial memory. Meanwhile, CB2, TRPV3, and TRPV4 expressions were not altered at diverse concentrations of DHA. We concluded that some subtypes of endocannabinoid/endovanilloid receptors might be involved in enhanced spatial memory induced by DHA supplementation.