X-shooter is the first 2nd generation instrument of the ESO Very Large Telescope(VLT). It is a very efficient, single-target, intermediate-resolution spectrograph that was installed at the Cassegrain ...focus of UT2 in 2009. The instrument covers, in a single exposure, the spectral range from 300 to 2500 nm. It is designed to maximize the sensitivity in this spectral range through dichroic splitting in three arms with optimized optics, coatings, dispersive elements and detectors. It operates at intermediate spectral resolution (R~4,000 - 17,000, depending on wavelength and slit width) with fixed echelle spectral format (prism cross-dispersers) in the three arms. It includes a 1.8"x4" Integral Field Unit as an alternative to the 11" long slits. A dedicated data reduction package delivers fully calibrated two-dimensional and extracted spectra over the full wavelength range. We describe the main characteristics of the instrument and present its performance as measured during commissioning, science verification and the first months of science operations.
Measuring repolarization characteristics is challenging and has been reserved for experienced physicians. In electrocardiographic imaging (ECGI), activation-recovery interval (ARI) is used as a ...measure of local cardiac repolarization duration. We hypothesized that repolarization characteristics, such as local electrogram morphology and local and global dispersion of repolarization timing and duration could be of significance in ECGI.
To further explore their potential in arrhythmic risk stratification we investigated the use of novel repolarization parameters in ECGI.
We developed and compared methods for T-peak and T-end detection in reconstructed potentials. All methods were validated on annotated reconstructed electrograms (EGMs). Characteristics of the reconstructed EGMs and epicardial substrate maps in IVF patients were analyzed by using data recorded during sinus rhythm. The ECGI data were analyzed for EGM morphology, conduction, and repolarization.
We acquired ECGI data from 8 subjects for this study. In all patients we evaluated four repolarization parameters: Repolarization time, T-wave area, Tpeak-Tend interval, and T-wave alternans. Most prominent findings were steep repolarization time gradients in regions with flat EGMs. These regions were also characterized by low T-wave area and large differences in Tpeak-Tend interval.
Measuring novel repolarization parameters in reconstructed electrograms acquired with ECGI is feasible, can be done in a fully automated manner and may provide additional information on underlying arrhythmogenic substrate for risk stratification. Further studies are needed to investigate their potential use and clinical application.
To explore sleep structure in participants with obstructive sleep apnea (OSA) and comorbid insomnia (COMISA) and participants with OSA without insomnia (OSA-only) using both single-night ...polysomnography and multi-night wrist-worn photoplethysmography/accelerometry.
Multi-night 4-class sleep-staging was performed with a validated algorithm based on actigraphy and heart rate variability, in 67 COMISA (23 women, median age: 51 years) and 50 OSA-only (15 women, median age: 51) participants. Sleep statistics were compared using linear regression models and mixed-effects models. Multi-night variability was explored using a clustering approach and between- and within-participant analysis.
Polysomnographic parameters showed no significant group differences. Multi-night measurements, during 13.4 ± 5.2 nights per subject, demonstrated a longer sleep onset latency and lower sleep efficiency for the COMISA group. Detailed analysis of wake parameters revealed longer mean durations of awakenings in COMISA, as well as higher numbers of awakenings lasting 5 min and longer (WKN≥5min) and longer wake after sleep onset containing only awakenings of 5 min or longer. Within-participant variance was significantly larger in COMISA for sleep onset latency, sleep efficiency, mean duration of awakenings and WKN≥5min. Unsupervised clustering uncovered three clusters; participants with consistently high values for at least one of the wake parameters, participants with consistently low values, and participants displaying higher variability.
Patients with COMISA more often showed extended, and more variable periods of wakefulness. These observations were not discernible using single night polysomnography, highlighting the relevance of multi-night measurements to assess characteristics indicative for insomnia.
•Single-night sleep measurements show limited value in the differentiation between OSA and COMISA.•COMISA patients more often show extended periods of wakefulness over multiple nights.•Combined photoplethysmography and actigraphy can adequately capture these differences.•Multi-night assessment is useful to objectively identify comorbid insomnia and prompt further investigation.
In 1982 the Netherlands made a unilateral decision to change the established airway–breathing–circulation (ABC) training sequence to a different approach that stressed efficiency in diagnosis and ...treatment. This Dutch approach became known as the CAB (circulation–airway–breathing) sequence. Twenty years later, being confronted with the new international guidelines (published 2000) that still use the ABC approach, the Netherlands Resuscitation Council (NRR) questioned again the validity of our persistence in using the “Dutch variant” of resuscitation. This resulted in revised national guidelines that conform again with the international guidelines.
This article restates the main rationale and arguments behind the original decision to change to a Dutch (CAB) version of resuscitation over 20 years ago. The national decision to adopt the ABC approach once again was mainly to prevent resuscitation in the Netherlands from being isolated from the rest of the world and was not based on present knowledge of physiology and resuscitation. The authors hope that this article will open the discussion once again.
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