Estimation and analysis of multi-GNSS differential code biases using a hardware signal simulator

In ionospheric modeling, the differential code biases (DCBs) are a non-negligible error source, which are routinely estimated by the different analysis centers of the International GNSS Service (IGS) as a by-product of their global ionospheric analysis. These are, however, estimated only for the IGS station receivers and for all the satellites of the different GNSS constellations. A technique is proposed for estimating the receiver and satellites DCBs in a global or regional network by first estimating the DCB of one receiver set as reference. This receiver DCB is then used as a ‘known’ parameter to constrain the global ionospheric solution, where the receiver and satellite DCBs are estimated for the entire network. This is in contrast to the constraint used by the IGS, which assumes that the involved satellites DCBs have a zero mean. The ‘known’ receiver DCB is obtained by simulating signals that are free of the ionospheric, tropospheric and other group delays using a hardware signal simulator. When applying the proposed technique for Global Positioning System legacy signals, mean offsets in the order of 3 ns for satellites and receivers were found to exist between the estimated DCBs and the IGS published DCBs. It was shown that these estimated DCBs are fairly stable in time, especially for the legacy signals. When the proposed technique is applied for the DCBs estimation using the newer Galileo signals, an agreement at the level of 1–2 ns was found between the estimated DCBs and the manufacturer’s measured DCBs, as published by the European Space Agency, for the three still operational Galileo in-orbit validation satellites

Dietary fatty acid pattern and preferences are not associated with fatty acid transporter CD36 in diabetic patients

41st FEBS Congress on Molecular and Systems Biology for a Better Life -- SEP 03-08, 2016 -- Kusadasi, TURKEYKISA, Ucler/0000-0002-8131-6810WOS: 000383616901052…FEB

Impact of Genotype, Serum Bile Acids, and Surgical Biliary Diversion on Native Liver Survival in FIC1 Deficiency

Mutations in ATP8B1 can lead to familial intrahepatic cholestasis type 1 (FIC1) deficiency, or progressive familial intrahepatic cholestasis type 1 (PFIC1). The rarity of FIC1 deficiency has largely prevented a detailed analysis of its natural history, effects of predicted protein truncating mutations (PPTMs), and possible associations of serum bile acid (sBA) concentrations and surgical biliary diversion (SBD) with long-term outcome. We aimed to provide novel insights by using the largest genetically defined cohort of FIC1 deficiency patients to date. This multicenter, combined retrospective and prospective study included 130 patients with compound heterozygous or homozygous predicted pathogenic ATP8B1 variants. Patients were categorized according to the number of PPTMs (i.e., splice site, frameshift due to deletion or insertion, nonsense, duplication); FIC1-A (n=67; no PPTM), FIC1-B (n=29; one PPTM) or FIC1-C (n=34; two PPTMs). Survival analysis showed an overall native liver survival (NLS) of 44% at age 18y. NLS was comparable between FIC1-A, FIC1-B, and FIC1-C (%NLS at age 10y: 67%, 41%, and 59%, respectively; P=0.12), despite FIC1-C undergoing SBD less often (%SBD at age 10y: 65%, 57%, and 45%, respectively; P=0.03). sBAs at presentation were negatively associated with NLS (NLS at age 10y; sBAs <194 µmol/L: 49% versus sBAs ≥194 µmol/L: 15%; P=0.03). SBD decreased sBAs (230 [125-282] to 74 [11-177] μmol/L; P=0.005). SBD (HR 0.55, 95% CI 0.28-1.03, P=0.06) and post-SBD sBA concentrations <65μmol/L (P=0.05) tended to be associated with improved NLS. Conclusion: Less than half of FIC1 deficiency patients reach adulthood with native liver. The number of PPTMs did not associate with the natural history or prognosis of FIC1 deficiency. sBA concentrations at initial presentation and after SBD provide limited prognostic information on long-term NLS