PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 16687836

SEDEM, a software package for EXAFS data extraction and modelling.

D Aberdam
View original source ↗Export metadata ↓

Abstract

A software package for extended X-ray absorption fine structure (EXAFS) data extraction and modelling, running on DOS- or Windows-operated PCs, is described. This package is written with the aim of giving the user a tool to undertake all steps of data processing and modelling, rather than making use of the most recent programming facilities. However, it remains easy to use, and self-explanatory to those who have already worked with EXAFS. It is divided into two main executable pieces of software. The first one is used to extract the EXAFS k(n)chi(k) function from the data and isolate the shell contributions by Fourier filtering. A tool to sum the spectra before EXAFS extraction is provided. The second one is designed to model the EXAFS spectra or the shell contributions, using amplitude and phase data either from McKale's tables, computed from the FEFF program or extracted from experimental reference spectra. This modelling program allows either an optimization of the simulation by a least-mean-square gradient algorithm, with a statistical evaluation of the result of optimization, or, in the case of a single shell, a direct determination of the four main parameters (neighbour distance and number, energy shift and Debye-Waller factor) by decorrelation of the phase and amplitude. In the presence of anharmonicity, the cumulant expansion of the radial distribution of distances is obtained from the phase and amplitude decorrelation. This package is in use at the Collaborative Research Group on Interfaces (CRG-IF) bending-magnet #32 X-ray line (BM-32) at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France.

Explore related subjects

Journal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

D Aberdam. 1998-09-01. SEDEM, a software package for EXAFS data extraction and modelling.. https://doi.org/10.1107/s0909049598004142

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2027

Effectiveness of high-dose versus standard-dose influenza vaccines against hospitalisation according to frailty risk: a prespecified analysis of the randomised trial DANFLU-2.

BACKGROUND: Frailty is a major risk factor for influenza-related complications and can influence vaccine effectiveness. We aimed to assess the relative vaccine effectiveness (rVE) of high-dose (HD-IIV) versus standard-dose inactivated influenza vaccine (SD-IIV) in older adults aged 65 years or older according to frailty risk. METHODS: This study was a prespecified analysis of DANFLU-2, an open-label, individually randomised trial, conducted in Denmark during three consecutive influenza seasons (2022-23, 2023-24, and 2024-25). Adults aged 65 years or older were randomised (1:1) to the HD-IIV or SD-IIV group. The primary endpoint was hospitalisation for influenza or pneumonia. Frailty was defined according to the validated Hospital Frailty Risk Score (HFRS) based on ICD-10 codes within 10 years before randomisation. Participants were stratified into three HFRS categories, namely low (<5 points), intermediate (5-15 points), and high (>15 points) frailty risk. The rVE of HD-IIV versus SD-IIV against the primary endpoint was assessed across prespecified HFRS categories and treating HFRS as a continuous variable. Pearson's chi-square test was used to compare safety events across frailty risk groups and randomisation groups. FINDINGS: Among 332&#x2009;438 randomised participants (mean age 73&#xb7;7 years [SD 5&#xb7;8]; 161&#x2009;538 [48&#xb7;6%] were female), 276&#x2009;173 (83&#xb7;1%) had low frailty risk, 52&#x2009;395 (15&#xb7;8%) had intermediate frailty risk, and 3861 (1&#xb7;2%) had high frailty risk. The primary endpoint of hospitalisation for influenza or pneumonia occurred in 1424 (0&#xb7;5%) of 276&#x2009;173 participants with low frailty risk, 761 (1&#xb7;5%) of 52&#x2009;395 with intermediate frailty risk, and 163 (4&#xb7;2%) of 3861 with high frailty risk (relative risk [RR] for intermediate vs low frailty risk 2&#xb7;8 [95% CI 2&#xb7;6-3&#xb7;1]; RR for high vs low frailty risk 8&#xb7;2 [7&#xb7;0-9&#xb7;6]). HFRS as a continuous variable significantly modified the effect of HD-IIV versus SD-IIV against the primary endpoint with higher rVE estimates with increasing HFRS (pinteraction=0&#xb7;020). The rVE was 0&#xb7;2% (95% CI -10&#xb7;8 to 10&#xb7;2) among those with low frailty risk, 13&#xb7;1% (-0&#xb7;4 to 24&#xb7;8) among those with intermediate frailty risk, and 19&#xb7;9% (-10&#xb7;3 to 42&#xb7;1) among those with high frailty risk. No significant interaction was observed when HFRS was assessed according to the prespecified categorical frailty groups (pinteraction=0&#xb7;17). The proportion of participants with at least one serious adverse event increased across frailty risk groups (13&#x2009;366 [4&#xb7;8%] of 275&#x2009;795 for low frailty risk, 5475 [10&#xb7;5%] of 52&#x2009;315 for intermediate frailty risk, and 777 [20&#xb7;2%] of 3850 for high frailty risk; p<0&#xb7;0001), with similar proportions of serious adverse events in the HD-IIV and SD-IIV groups for each frailty risk group. INTERPRETATION: Among adults aged 65 years or older in Denmark, frailty risk might modify the effects of HD-IIV versus SD-IIV against hospitalisation for influenza or pneumonia, with higher rVE estimates with increasing frailty risk. These findings might support considering high-dose influenza vaccines for frail older adults. However, effect modification was not evident when frailty was assessed using prespecified categorical subgroups, and subgroup-specific estimates were imprecise, with 95% CIs crossing the null. These results should be considered exploratory, warranting further investigation. FUNDING: The DANFLU-2 trial was funded by Sanofi.

Journal Article↗