3 research outputs found
Fouling-resistant PVDF nanofibre membranes for the desalination of brackish water in membrane distillation
In the current study, pristine PVDF nanofibre membranes were successfully modified with silica nanoparticles (SiO(2)NPs) or with organically-functionalised (silanised) silica nanoparticles (f-SiO(2)NPs). The superhydrophobic f-SiO(2)NPs-modified PVDF membranes (contact angle = 156 +/- 6 degrees) showed enhanced water flux and lower flux decays than those of pristine and SiO(2)NPs-modified PVDF membranes under both low salinity (LS) and high salinity (HS) feed solution conditions. Nevertheless, the higher organic content of the LS feed exacerbated fouling and wetting in both pristine and modified membranes (i.e., flux decays of up to 73.6% in uncoated membrane samples). These results indicate the efficiency of the silanisation of f-SiO(2)NPs in attaining super-hydrophobicity and enhanced performance in modified PVDF membranes. However, fouling and wetting still had a negative impact on the performance of the f-SiO(2)NPs-modified PVDF membranes. To provide anti-fouling properties, a hydrophilic layer consisting of silver nanoparticles (AgNPs) and functionalised multi-walled carbon nanotubes (f-MWCNTs) was coated on the pristine and modified membranes. This layer significantly decreased the flux decay and enhanced the resistance towards a decay in salt rejection of pristine, SiO(2)NPs-modified, and f-SiO(2)NPs-modified PVDF membranes under both LS and HS feed solution conditions. The adsorption of foulants also changed the surface characteristics of both coated and uncoated membranes, as evidenced by a decrease in contact angle and increase in interfacial free energy. The hydrophilic coating layer provided fouling-resistance properties, high salt rejection, and low flux decays to hydrophobic PVDF nanofibre membranes, demonstrating the high potential of this technique to produce potable water from brackish water in Membrane Distillation processes
A Novel 8-Predictors Signature to Predict Complicated Disease Course in Pediatric-onset Crohn’s Disease: A Population-based Study
International audienceBackground The identification of patients at high risk of a disabling disease course would be invaluable in guiding initial therapy in Crohn’s disease (CD). Our objective was to evaluate a combination of clinical, serological, and genetic factors to predict complicated disease course in pediatric-onset CD. Methods Data for pediatric-onset CD patients, diagnosed before 17 years of age between 1988 and 2004 and followed more than 5 years, were extracted from the population-based EPIMAD registry. The main outcome was defined by the occurrence of complicated behavior (stricturing or penetrating) and/or intestinal resection within the 5 years following diagnosis. Lasso logistic regression models were used to build a predictive model based on clinical data at diagnosis, serological data (ASCA, pANCA, anti-OmpC, anti-Cbir1, anti-Fla2, anti-Flax), and 369 candidate single nucleotide polymorphisms. Results In total, 156 children with an inflammatory (B1) disease at diagnosis were included. Among them, 35% (n = 54) progressed to a complicated behavior or an intestinal resection within the 5 years following diagnosis. The best predictive model (PREDICT-EPIMAD) included the location at diagnosis, pANCA, and 6 single nucleotide polymorphisms. This model showed good discrimination and good calibration, with an area under the curve of 0.80 after correction for optimism bias (sensitivity, 79%, specificity, 74%, positive predictive value, 61%, negative predictive value, 87%). Decision curve analysis confirmed the clinical utility of the model. Conclusions A combination of clinical, serotypic, and genotypic variables can predict disease progression in this population-based pediatric-onset CD cohort. Independent validation is needed before it can be used in clinical practice