The influence of cell window imperfections on the calibration and measured data of two types of rotating-analyzer ellipsometers

A graphical method has been developed to determine the plane of incidence in the presence of cell windows with small retardation. For two types of rotating-analyzer ellipsometers, expressions have been derived that relate the experimental parameters and the elements of the Mueller imperfection matrices of the windows. These matrices can be determined by measuring with and without cell windows. Measurements have been performed with three samples with different optical constants

Spectroscopic ellipsometric investigation of the clean and oxygen exposed Ni(110) surface

Dynamical ellipsometric investigations of the initial oxidation of the Ni(110) surface have been performed. Ellipsometry appears to be well suited to distinguish between chemisorbed oxygen and nickel oxide on the surface. Annealing at 740 K causes the nucleation of nickel oxide to proceed faster than at 570 K. After equal exposures however, the nucleation is slower with an oxygen pressure of 2 × 10−7 Torr than with a pressure of 1.3 × 10−8 Torr. Spectroscopic ellipsometric measurements (400–800 nm) have been performed on clean and oxygen-exposed (at saturation) Ni(110) surfaces. The complex dielectric function of the clean surface has been determined. To explain the results of the oxygen exposed surface a model is discussed — a surface layer with a thickness of 6 Å and a mixture of 90% NiO and 10% Ni — in which changes with substrate optical properties are taken into account

An AES and LEED study of carbon and oxygen sorption on copper surfaces

The sorption of carbon and oxygen on cooper surfaces has been studied by AES and LEED. The carbon coverage has been estimated by measuring the substrate Auger peak attenuation upon changing the carbon coverage and by studying the coadsorption of oxygen and carbon on the surface. The effect of carbon on the background of derivative spectra is also reported

Spectroscopic ellipsometric investigation of clean and oxygen covered copper single crystal surfaces

Spectroscopic ellipsometric measurements (400–820 nm) have been performed on clean and oxygen covered Cu(110) and Cu(111) surfaces in an AES-LEED UHV system. The complex dielectric functions of the clean surfaces were calculated from measurements between room temperature and 600 K. In contrast with Cu(111), for the Cu(110) surface the ellipsometric parameters Δ and Ψ depend on the azimuth of the plane of incidence of the light beam. Such an anisotropy was also found for the changes in Δ and Ψ measured upon adsorption of oxygen to coverages corresponding with approximately 1/2 and 1 monolayer. To explain the results, several models are discussed, in which changes with substrate optical properties are taken into account

The adsorption and decomposition of carbon monoxide on Ni(100) and the oxidation of the surface carbide by oxygen

The interaction of carbon monoxide with Ni(100) has been studied by ellipsometry and Auger electron spectroscopy. Bombardment by electrons of a relatively high energy (2500 eV) leads to the disproportionation of the adsorbed CO (2 COad → Cad + CO2g ). The rate of oxidation of this surface carbide is , where hc is the carbon 272 eV Auger peak height, n=0.5 and the apparent activation energy Eact =13.3 kcal/mole. This relation is valid at 200–400°C and at oxygen pressures of 5 × 10−9−8 × 10−7 Torr

Interaction of oxygen with an AISI 314 stainless steel surface studied by ellipsometry and auger electron spectroscopy in combination with ion bombardment

The influence of pretreatment (ion bombardment) on the initial oxidation of AISI 314 stainless steel has been investigated in ultra high vacuum systems with ellipsometry and Auger electron spectroscopy. The bombardment was carried out with Ar+ ions with energies up to 2.2 keV at various doses and angles of incidence. Oxidation was performed at low Pos (< 10−5 Torr) and sample temperatures (<300°C). The worked layer was removed with low-energy argon ions. High energy bombardment causes an increase in oxidation rate and higher values of the real and imaginary part of the refractive index as compared to the undisturbed sample. The rate and extent of oxidation increases with increasing energy, dose and angle of incidence of the ion beam. The outermost part of the oxide is enriched in iron while the region near the substrate contains more nickel and chromium

The genetic basis of apparently idiopathic ventricular fibrillation:A retrospective overview

Aims: During the diagnostic work-up of patients with idiopathic ventricular fibrillation (VF), next-generation sequencing panels can be considered to identify genotypes associated with arrhythmias. However, consensus for gene panel testing is still lacking, and variants of uncertain significance (VUS) are often identified. The aim of this study was to evaluate genetic testing and its results in idiopathic VF patients. Methods and results: We investigated 419 patients with available medical records from the Dutch Idiopathic VF Registry. Genetic testing was performed in 379 (91%) patients [median age at event 39 years (27-51), 60% male]. Single-gene testing was performed in 87 patients (23%) and was initiated more often in patients with idiopathic VF before 2010. Panel testing was performed in 292 patients (77%). The majority of causal (likely) pathogenic variants (LP/P, n = 56, 15%) entailed the DPP6 risk haplotype (n = 39, 70%). Moreover, 10 LP/P variants were found in cardiomyopathy genes (FLNC, MYL2, MYH7, PLN (two), TTN (four), RBM20), and 7 LP/P variants were identified in genes associated with cardiac arrhythmias (KCNQ1, SCN5A (2), RYR2 (four)). For eight patients (2%), identification of an LP/P variant resulted in a change of diagnosis. In 113 patients (30%), a VUS was identified. Broad panel testing resulted in a higher incidence of VUS in comparison to single-gene testing (38% vs. 3%, P &lt; 0.001). Conclusion: Almost all patients from the registry underwent, albeit not broad, genetic testing. The genetic yield of causal LP/P variants in idiopathic VF patients is 5%, increasing to 15% when including DPP6. In specific cases, the LP/P variant is the underlying diagnosis. A gene panel specifically for idiopathic VF patients is proposed.</p