Thermochemical stability and nonstoichiometry of erbia-stabilized bismuth oxide

A phase study has been performed of high oxygen ion conducting erbia-stabilized bismutch oxide (1-x)Bi2O3·xEr2O3 (BE100X) using thermal analysis and X-ray powder diffraction. Investigation of the effect of a long-time (500 h) anneal of samples at 650°C in air revealed that the minimum amount of erbia needed to stabilize the high-temperature cubic ¿-Bi2O3 phase is 27.5 at%. This boundary value is much larger than the one usually reported in literature where the sluggishenss of the transformation from cubic to hexagonal at high Bi contents is not taken into account. Changes in nonstoichiometry of solid solutions Bi2-2xEr2xO3+¿ between 550°C and 850°C upon varying the ambient oxygen partial pressure are minimal for samples with 27.5 at% erbia, increasing with increasing erbia content. The parameter ¿ in pure oxygen increases from 0. 0044 for BE27.5 to 0.022 for BE50 taking the composition in nitrogen (PO2 ¿ 10¿4 atm) as stoichiometric reference (¿ = 0)

Three electrode current voltage measurements on erbia stabilized bismuth oxide with co-pressed gold gauze electrodes

The polarization behaviour of (Bi2O3)0.75(Er2O3)0.25(BE25) with a co-pressed gold gauze electrode was studied as a function of temperature and oxygen partial pressure in a three electrode cell. The anodic polarization is smaller than the cathodic polarization. The cathodic charge transfer coefficient, αc, is about 0.5 while the anodic one, αa, is about 1.5. The exchange current density shows a (PO2) dependence for partial pressures below 1 atm with an activation enthalpy of ˜126 kJ mol−1. These values compare well with results obtained from 18O exchange experiments. Current densities for the co-pressed gold gauze electrodes are about a factor of 5 to 10 larger than found for the previously reported porous sputtered gold electrodes. Analysis of the electrode impedance shows strong influence of surface diffusion on the electrode reaction, which must take place at the surface of the electrolyte

Modified CVD of nanoscale structures in and EVD of thin layers on porous ceramic membranes

Experiments on the modified chemical vapour deposition (CVD) and the electrochemical vapour deposition (EVD) of yttria-stabilized zirconia on porous substrates are reported. It is shown that, in the CVD stage, deposition occurs in a small (<20 um) region at the edge of the substrate, very likely leading to pore narrowing. This result illustrates the feasibility of the CVD technique for the modification of ceramic membranes to the (sub)nanometer scale. Film growth in the EVD stage is shown to be controlled by the inpore diffusion of the oxygen source reactant for short (<5 h) deposition times. The yttria to zirconia ratio in the deposited film is determined by the ratio present in the vapour phase. Very thin (<2 um) films can be deposited, which have a potential application in solid oxide fuel cells

Limited diagnostic accuracy and clinical impact of single-operator peroral cholangioscopy for indeterminate biliary strictures

BACKGROUND: Single-operator peroral cholangioscopy (sPOCS) is considered a valuable diagnostic modality for indeterminate biliary strictures. Nevertheless, studies show large variation in its characteristics and measures of diagnostic accuracy. Our aim was to estimate the diagnostic accuracy of sPOCS visual assessment and targeted biopsies for indeterminate biliary strictures. Additional aims were: estimation of the clinical impact of sPOCS and comparison of diagnostic accuracy with brush cytology. METHODS: A retrospective single-center study of adult patients who underwent sPOCS for indeterminate biliary strictures was performed. Diagnostic accuracy was defined as sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The clinical impact of sPOCS was assessed by review of medical records, and classified according to its influence on patient management. RESULTS: 80 patients were included, with 40 % having primary sclerosing cholangitis (PSC). Prior ERCP was performed in 88 %, with removal of a biliary stent prior to sPOCS in 55 %. The sensitivity, specificity, PPV, and NPV for sPOCS visual impression and targeted biopsies were 64 %, 62 %, 41 %, and 84 %, and 15 %, 65 %, 75 %, and 69 %, respectively. The clinical impact of sPOCS was limited; outcome changed management in 17 % of patients. Sequential brush cytology sensitivity, specificity, PPV, and NPV were 47 %, 95 %, 80 %, and 83 %. CONCLUSIONS: The diagnostic accuracy of sPOCS for indeterminate biliary strictures was found to be inferior to brush cytology, with a low impact on patient management. These findings are obtained from a select patient population with a high prevalence of PSC and plastic stents in situ prior to sPOCS

Non-alcoholic fatty liver disease: identical etiologic factors in patients with type 1 and type 2 diabetes

Aims: To compare NAFLD prevalence, distribution and its etiologic determinants in patients with type 1 diabetes (T1D) and type 2 diabetes (T2D). Methods: In this cross-sectional study, NAFLD was evaluated by transient elastography in adult outpatients with T1D and T2D. NAFLD was defined as hepatic steatosis with or without fibrosis. Associations between insulin resistance related factors and NAFLD and advanced fibrosis (≥ F3) were explored in T1D and T2D separately, using multivariate logistic regression models. Interaction analysis was performed to compare the associations in patients with T1D and T2D. Results: One hundred and fifty patients with T1D (mean age 47 years, male 55%, mean diabetes duration 25 years, median BMI 25 kg/m2) and 100 patients with T2D (median age 67 years, male 56%, median diabetes duration 17 years, mean BMI 30 kg/m2) were included. NAFLD prevalence was 20% in patients with T1D and 76% in patients with T2D. Advanced fibrosis prevalence was 2.0% in patients with T1D and 22% in patients with T2D. In both patients with T1D and T2D, waist circumference, BMI and metabolic syndrome were positively associated, and estimated insulin sensitivity was negatively associated with the presence of NAFLD, adjusted for age, sex and diabetes duration. There was no effect modification by diabetes type for any of these associations. Conclusions: Despite differences in population characteristics and pathophysiology between T1D and T2D, insulin resistance related factors are similarly associated with NAFLD in both groups

DDA1, a novel factor in transcription-coupled repair, modulates CRL4CSA dynamics at DNA damage-stalled RNA polymerase II

Transcription-blocking DNA lesions are specifically targeted by transcription-coupled nucleotide excision repair (TC-NER), which removes a broad spectrum of DNA lesions to preserve transcriptional output and thereby cellular homeostasis to counteract aging. TC-NER is initiated by the stalling of RNA polymerase II at DNA lesions, which triggers the assembly of the TC-NER-specific proteins CSA, CSB and UVSSA. CSA, a WD40-repeat containing protein, is the substrate receptor subunit of a cullin-RING ubiquitin ligase complex composed of DDB1, CUL4A/B and RBX1 (CRL4CSA). Although ubiquitination of several TC-NER proteins by CRL4CSA has been reported, it is still unknown how this complex is regulated. To unravel the dynamic molecular interactions and the regulation of this complex, we applied a single-step protein-complex isolation coupled to mass spectrometry analysis and identified DDA1 as a CSA interacting protein. Cryo-EM analysis showed that DDA1 is an integral component of the CRL4CSA complex. Functional analysis revealed that DDA1 coordinates ubiquitination dynamics during TC-NER and is required for efficient turnover and progression of this process.<br/

A many-analysts approach to the relation between religiosity and well-being

The relation between religiosity and well-being is one of the most researched topics in the psychology of religion, yet the directionality and robustness of the effect remains debated. Here, we adopted a many-analysts approach to assess the robustness of this relation based on a new cross-cultural dataset (N=10,535 participants from 24 countries). We recruited 120 analysis teams to investigate (1) whether religious people self-report higher well-being, and (2) whether the relation between religiosity and self-reported well-being depends on perceived cultural norms of religion (i.e., whether it is considered normal and desirable to be religious in a given country). In a two-stage procedure, the teams first created an analysis plan and then executed their planned analysis on the data. For the first research question, all but 3 teams reported positive effect sizes with credible/confidence intervals excluding zero (median reported β=0.120). For the second research question, this was the case for 65% of the teams (median reported β=0.039). While most teams applied (multilevel) linear regression models, there was considerable variability in the choice of items used to construct the independent variables, the dependent variable, and the included covariates

A Many-analysts Approach to the Relation Between Religiosity and Well-being

The relation between religiosity and well-being is one of the most researched topics in the psychology of religion, yet the directionality and robustness of the effect remains debated. Here, we adopted a many-analysts approach to assess the robustness of this relation based on a new cross-cultural dataset (N = 10, 535 participants from 24 countries). We recruited 120 analysis teams to investigate (1) whether religious people self-report higher well-being, and (2) whether the relation between religiosity and self-reported well-being depends on perceived cultural norms of religion (i.e., whether it is considered normal and desirable to be religious in a given country). In a two-stage procedure, the teams first created an analysis plan and then executed their planned analysis on the data. For the first research question, all but 3 teams reported positive effect sizes with credible/confidence intervals excluding zero (median reported β = 0.120). For the second research question, this was the case for 65% of the teams (median reported β = 0.039). While most teams applied (multilevel) linear regression models, there was considerable variability in the choice of items used to construct the independent variables, the dependent variable, and the included covariates