Disentangling instrumental broadening

A new procedure aiming at disentangling the instrumental profile broadening and the relevant X-ray powder diffraction (XRPD) profile shape is presented. The technique consists of three steps: denoising by means of wavelet transforms, background suppression by morphological functions and deblurring by a Lucy--Richardson damped deconvolution algorithm. Real XRPD intensity profiles of ceria samples are used to test the performances. Results show the robustness of the method and its capability of efficiently disentangling the instrumental broadening affecting the measurement of the intrinsic physical line profile. These features make the whole procedure an interesting and user-friendly tool for the pre-processing of XRPD data.Comment: 9 pages, 1 table, 1 figure; typos correcte

Folding a 2-D powder diffraction image into a 1-D scan: a new procedure

A new procedure aiming at folding a powder diffraction 2-D into a 1-D scan is presented. The technique consists of three steps: tracking the beam centre by means of a Simulated Annealing (SA) of the diffraction rings along the same axis, detector tilt and rotation determination by a Hankel Lanczos Singular Value Decomposition (HLSVD) and intensity integration by an adaptive binning algorithm. The X-ray powder diffraction (XRPD) intensity profile of the standard NIST Si 640c sample is used to test the performances. Results show the robustness of the method and its capability of efficiently tagging the pixels in a 2-D readout system by matching the ideal geometry of the detector to the real beam-sample-detector frame. The whole technique turns out in a versatile and user-friendly tool for the $2\vartheta$ scanning of 2-D XRPD profiles.Comment: 11 pages, 1 table, 2 figure

Impact Of Sars-Cov-2 Variants On Vaccine Breakthrough Infections

SARS-CoV-2 variants of concern are defined by their increased intrinsic transmissibility and ability to evade immune recognition and neutralization, yet the relative importance of these factors in determining variant fitness in population settings is unclear. We hypothesize that as population level immunity has increased throughout the course of the pandemic, immune escape has played an increasingly important role in the emergence and sustained circulation of variants. Here, we use logistic regression models to estimate the odds of vaccine breakthrough infections for several major variants of concern in a population of Connecticut residents. We investigate the impact of immune escape on sustained variant circulation across 18 months of the pandemic and in four periods of variant emergence in the context of increasing vaccination uptake rates. We show significantly increased odds of vaccine breakthrough infections associated with the Omicron BA.1 variant relative to the Delta variant [2 vaccine doses ≥5 months adjusted OR: 2.093, 95% CI: 1.11 - 3.94 | 3 vaccine doses ≤5 months adjusted OR: 7.118, 95% CI: 1.44 - 35.17] as well as the Omicron BA.4 and BA.5 variants relative to the Omicron BA.2 variant [3 vaccine doses adjusted OR: 1.66, 95% CI: 1.01 - 2.73]. We also show significantly decreased odds of vaccine breakthrough infections associated with the Alpha variant relative to the pre-Alpha variant lineages [adjusted OR: 0.796, 95% CI: 0.73, 0.86] as well as decreasing age and female sex. These findings suggest immune escape played an important role in the emergence of the Omicron BA.1 variant and imply an important association between demographic characteristics and vaccine breakthrough infections

The Chromosomal Protein Sso7d of the CrenarchaeonSulfolobus solfataricus Rescues Aggregated Proteins in an ATP Hydrolysis-dependent Manner

In this work, we show that the nonspecific DNA-binding protein Sso7d from the crenarchaeon Sulfolobus solfataricus displays a cation-dependent ATPase activity with a pH optimum around neutrality and a temperature optimum of 70 degrees C. Measurements of tryptophan fluorescence and experiments that used 1-anilinonaphthalene-8-sulfonic acid as probe demonstrated that ATP hydrolysis induces a conformational change in the molecule and that the binding of the nucleotide triggers the ATP hydrolysis-induced conformation of the protein to return to the native conformation. We found that Sso7d rescues previously aggregated proteins in an ATP hydrolysis-dependent manner; the native conformation of Sso7d forms a complex with the aggregates, while the ATP hydrolysis-induced conformation is incapable of this interaction. Sso7d is believed to be the first protein isolated from an archaeon capable of rescuing aggregates

Expression of Major Histocompatibility Complex Antigens on Macrophages: Correlative Study Using Flow Cytometry, Radioimmunoassay, and Colloidal Gold Immunolabeling

Correlative scanning electron microscopy (SEM), radioimmunoassay (RIA), and flow cytometric analysis were used to characterize levels of class I and class II major histocompatibility complex-encoded (MHC) antigen expression on peritoneal exudate cells of mice chronically infected with Chlamydia psittaci. Analysis of peritoneal macrophages by all three techniques revealed a marked induction of H-2 K,D (class I) and I-A, l-E (class II) antigens on cells from infected C3H mice when compared to uninfected controls. Scanning electron micrographs further document that the increases in class I and II MHC antigens are due to an increase in la/H-2 bearing cells as well as an increase in MHC molecules/cell. These immune macrophages have a flattened morphology, almost completely devoid of the membrane ruffles and villi which are characteristic of control peritoneal macrophages. These studies suggest that while both flow cytometry and RIA can provide an accurate quantitative estimate of antigen expression in a cell population, the immunogold labeling technique can allow visualization of individual cells and additional analysis of the topographical distribution of cell surface antigens

Geochemical Characterization of Spring Waters in the Crati River Basin, Calabria (Southern Italy)

The characterization of the spatial variation of geochemical parameters in spring waters, especially the ones used for drinking purpose, is essential to identify potential risks to humans. In this work, results of a qualitative analysis on 190 samples of spring waters collected in the largest catchment of the Calabria region (southern Italy) are shown. Several physical and chemical parameters were analysed and the Langelier-Ludwig diagram was built to evaluate the hydrochemical facies of the sampled waters. Additionally, the relationships between water temperature and altitude and electric conductivity (EC) and altitude were assessed. Geostatistical methods were used to map the physical and chemical parameters. Results showed a good quality status of the spring waters in the Crati basin, with a predominant Ca-Mg-type hydrochemical facies. Then, a connection between EC and temperature with elevation has been detected in some area of the basin. Finally, the spatial analysis allowed identifying the distribution of the concentration of the several parameters