57 research outputs found

    Ultrathin graphene-based membrane with precise molecular sieving and ultrafast solvent permeation

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    Graphene oxide (GO) membranes continue to attract intense interest due to their unique molecular sieving properties combined with fast permeation. However, their use is limited to aqueous solutions because GO membranes appear impermeable to organic solvents, a phenomenon not yet fully understood. Here, we report efficient and fast filtration of organic solutions through GO laminates containing smooth two-dimensional (2D) capillaries made from large (10-20 μm) flakes. Without modification of sieving characteristics, these membranes can be made exceptionally thin, down to â 1/410 nm, which translates into fast water and organic solvent permeation. We attribute organic solvent permeation and sieving properties to randomly distributed pinholes interconnected by short graphene channels with a width of 1 nm. With increasing membrane thickness, organic solvent permeation rates decay exponentially but water continues to permeate quickly, in agreement with previous reports. The potential of ultrathin GO laminates for organic solvent nanofiltration is demonstrated by showing >99.9% rejection of small molecular weight organic dyes dissolved in methanol. Our work significantly expands possibilities for the use of GO membranes in purification and filtration technologies

    Connecting for Surgery: The Belgian Use Case on the Legal Aspects of the Digital Operating Room

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    Telecommunications technology is making its way into operating rooms by new developments in e-health. However, conflicts arise with existing legal principles regarding data protection. This paper deals with key elements of the interactions between data protection and evolution in e-health. The scope will be the digital operating room, where different health services and activities converge through networked technology, raising a number of privacy-related issues. For instance, the patient's health records and tools for recording surgical procedures could be integrated within the same platform, potentially leading to sensitive personal data linkage. Also the possible duration and reason of storage of surgical recordings, is a matter that remains largely unresolved in current practice. First, this paper will analyze the data exchanges of the digital operating room. As these will include personal patient data, it must be assessed whether and how the European framework on data protection can apply. Second, the regulatory regime of the manufacturers of the devices of the digital operating room will be analyzed. Can the current legal framework relating to e-health provide for suitable regulation for such devices? Drawing from experience gained in research projects, this paper aims to provide practical answers to often theoretical questions

    Overlapping spectra of SMAD4 mutations in juvenile polyposis (JP) and JP-HHT syndrome.

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    Juvenile polyposis (JP) and hereditary hemorrhagic telangiectasia (HHT) are clinically distinct diseases caused by mutations in SMAD4 and BMPR1A (for JP) and endoglin and ALK1 (for HHT). Recently, a combined syndrome of JP-HHT was described that is also caused by mutations in SMAD4. Although both JP and JP-HHT are caused by SMAD4 mutations, a possible genotype:phenotype correlation was noted as all of the SMAD4 mutations in the JP-HHT patients were clustered in the COOH-terminal MH2 domain of the protein. If valid, this correlation would provide a molecular explanation for the phenotypic differences, as well as a pre-symptomatic diagnostic test to distinguish patients at risk for the overlapping but different clinical features of the disorders. In this study, we collected 19 new JP-HHT patients from which we identified 15 additional SMAD4 mutations. We also reviewed the literature for other reports of JP patients with HHT symptoms with confirmed SMAD4 mutations. Our combined results show that although the SMAD4 mutations in JP-HHT patients do show a tendency to cluster in the MH2 domain, mutations in other parts of the gene also cause the combined syndrome. Thus, any mutation in SMAD4 can cause JP-HHT. Any JP patient with a SMAD4 mutation is, therefore, at risk for the visceral manifestations of HHT and any HHT patient with SMAD4 mutation is at risk for early onset gastrointestinal cancer. In conclusion, a patient who tests positive for any SMAD4 mutation must be considered at risk for the combined syndrome of JP-HHT and monitored accordingly
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