Dissociative recombination and electron-impact de-excitation in CH photon emission under ITER divertor-relevant plasma conditions

For understanding carbon erosion and redeposition in nuclear fusion devices, it is important to understand the transport and chemical break-up of hydrocarbon molecules in edge plasmas, often diagnosed by emission of the CH A^2\Delta - X^2\Pi Ger\"o band around 430 nm. The CH A-level can be excited either by electron-impact or by dissociative recombination (D.R.) of hydrocarbon ions. These processes were included in the 3D Monte Carlo impurity transport code ERO. A series of methane injection experiments was performed in the high-density, low-temperature linear plasma generator Pilot-PSI, and simulated emission intensity profiles were benchmarked against these experiments. It was confirmed that excitation by D.R. dominates at T_e < 1.5 eV. The results indicate that the fraction of D.R. events that lead to a CH radical in the A-level and consequent photon emission is at least 10%. Additionally, quenching of the excited CH radicals by electron impact de-excitation was included in the modeling. This quenching is shown to be significant: depending on the electron density, it reduces the effective CH emission by a factor of 1.4 at n_e=1.3*10^20 m^-3, to 2.8 at n_e=9.3*10^20 m^-3. Its inclusion significantly improved agreement between experiment and modeling

Germinal centres in diagnostic labial gland biopsies of patients with primary Sjogren's syndrome are not predictive for parotid MALT lymphoma development

Objective Patients with primary Sjogren's syndrome (pSS) have an increased risk of developing non-Hodgkin's lymphoma (NHL), particularly parotid gland mucosaassociated lymphoid tissue (MALT) lymphomas. Presence of germinal centres (GCs) in labial gland biopsies has been suggested as predictive factor for NHL. We assessed whether presence of GCs is increased in labial gland biopsies from patients with pSS who developed parotid MALT lymphoma, the dominant NHL-subtype in pSS, compared with patients with pSS who did not develop lymphoma. Methods Eleven labial gland biopsies from patients with pSS that were taken prior to parotid MALT lymphoma development were compared with biopsies of 22 matched pSS controls (1: 2) who did not develop lymphoma. Biopsies were evaluated for GCs (H&E and Bcl6). Results Labial gland biopsies of pSS MALT lymphoma patients, revealed GCs in 2/11 (18%) H&E sections and 3/11 (27%) Bcl6 stained sections. In controls, GCs were present in 4/22 (18%) of H&E sections and 5/22 (23%) of Bcl6 stained sections. Conclusion P resence of GCs in labial gland biopsies does not differ between patients with pSS that develop parotid MALT lymphoma and patients with pSS who do not develop lymphoma. The presence of GCs in labial gland biopsies is therefore not a predictive factor for pSS-associated parotid MALT lymphomas

Psychosexual Functioning of Cognitively-able Adolescents with Autism Spectrum Disorder Compared to Typically Developing Peers

To gain further insight into psychosexual functioning, including behaviors, intrapersonal and interpersonal aspects, in adolescents with Autism Spectrum Disorder (ASD), comprehensive, multi-informant measures are needed. This study describes (1) the development of a new measure of psychosexual functioning in both parent- and self-reports (Teen Transition Inventory; TTI) covering all three domains of psychosexual functioning (i.e. psychosexual socialization, psychosexual selfhood, and sexual/intimate behavior). And (2) the initial testing of this instrument, comparing adolescents with ASD (n = 79 parent-report; n = 58 self-report) to Typically Developing (TD) adolescents (n = 131 parent-report; n = 91 self-report) while taking into account gender as a covariate. Results from both informants indicate more difficulties regarding psychosexual socialization and psychosexual selfhood in the ASD group. With regard to sexual/intimate behavior, only parents reported significantly more problems in adolescents with ASD

Bcl6 for identification of germinal centres in salivary gland biopsies in primary Sjogren's syndrome

Histopathological assessment of salivary gland biopsies is an important element of the diagnostic work-up of Sjögren's syndrome (SS) (Fox, 2017; Kroese et al., 2018). Microscopic evaluation of salivary glands of primary SS (pSS) patients reveals characteristic periductal lymphocytic infiltrates (foci), which mainly consist of T- and B-lymphocytes, as well as a variety of non-lymphoid cells, including dendritic cells and macrophages. Over time, these infiltrates may become organised to ectopic lymphoid tissue with T/B cell compartmentalisation, presence of CD21+ follicular dendritic cell (FDC) networks and high endothelial venules (Fisher et al., 2017; Kroese et al., 2014; Kroese et al., 2018; Salomonsson et al., 2003)

Nothing moves a surface: vacancy mediated surface diffusion

We report scanning tunneling microscopy observations, which imply that all atoms in a close-packed copper surface move frequently, even at room temperature. Using a low density of embedded indium `tracer' atoms, we visualize the diffusive motion of surface atoms. Surprisingly, the indium atoms seem to make concerted, long jumps. Responsible for this motion is an ultra-low density of surface vacancies, diffusing rapidly within the surface. This interpretation is supported by a detailed analysis of the displacement distribution of the indium atoms, which reveals a shape characteristic for the vacancy mediated diffusion mechanism that we propose.Comment: 4 pages; for associated movie, see http://www-lion.leidenuniv.nl/sections/cm/groups/interface/projects/therm

Parotid salivary sodium levels of Sjögren's syndrome patients suggest B-cell mediated epithelial sodium channel disruption

Patients with primary Sjögren's syndrome (SS) suffer widely from lack of saliva production. Here we investigate potential mechanisms underpinning changes in SS patient saliva composition. Sodium concentration was significantly higher in all saliva samples collected: unstimulated submandibular/sublingual (SmSl) saliva (p<0.0001), stimulated SmSl saliva (p=0.002) and stimulated parotid (PG) (p<0.0001) saliva, compared to non-SS sicca controls. Chloride, phosphate and potassium ion concentrations, α-amylase activity and total protein content correlations were less consistently changed between SS and non-SS saliva types. Stimulated PG salivary sodium levels correlated with the degree of CD45+ lymphocytic cell infiltrate in the parotid glands (r=0.69, p<0.001), and even more strongly so with infiltrating CD20+ B cells (r=0.73, p<0.0001). CD3+ T cells were only moderately correlated with salivary sodium (r=0.23, p=0.015). In non-SS control or focus score (FS) negative SS PG tissue, the epithelial sodium channel (ENaC), responsible for sodium transport out of saliva, was localised to the apical membrane of luminal striated duct cells. In PG tissue from FS+ SS patients, apical ENaC expression appeared absent. We hypothesise that B cell-related proinflammatory cytokines in SS salivary glands may dysregulate sodium transport channels in SS