Evaluating the Effectiveness of the COPD Assessment Test (CAT) in Screening for Chronic Obstructive Pulmonary Disease.

Background: Chronic obstructive pulmonary disease (COPD) is a major public health problem that remains largely under-diagnosed, mainly due to the under-use of spirometry to establish the diagnosis. The aim of this study is to evaluate the effectiveness of the Moroccan Arabic dialect version of the COPD Assessment Test (CAT) in screening for COPD. Methods: This was a cross-sectional study carried out in primary care facilities in Morocco, involving participants aged 40 and over. The performance of CAT in detecting cases of COPD was measured with reference to the results of spirometry, considered to be the gold Standard. Results: A total of 477 participants were included in the study. The prevalence of COPD was 6.7%. Internal consistency of the Moroccan Arabic dialect version of the CAT was high, with a Cronbach's alpha of 0.89. The total score of the CAT and of each item was significantly higher in subjects with COPD than in those without (P=0.000). Significantly negative correlations were found between CAT total score and FEV1 (r = -0.33, p=0.000), CAT and FVC (r = -0.22, p=0.000), CAT and FEV1/FVC ratio (r = -0.22, p=0.000). The receiver operating characteristic curve showed an area under the curve of 0.93. A CAT score of 10 was the optimal cut-off value for COPD screening, with a sensitivity, specificity, positive predictive value, and negative predictive value of 78.1%, 93.9%, 48.1% and 98.4%, respectively. Conclusion: The results of the present study showed that the CAT could be used as a screening tool for COPD. The use of this tool by healthcare professionals in primary care settings will improve and promote early diagnosis of this chronic disease.

NOMAD spectrometer on the ExoMars trace gas orbiter mission: part 2-design, manufacturing, and testing of the ultraviolet and visible channel.

NOMAD is a spectrometer suite on board the ESA/Roscosmos ExoMars Trace Gas Orbiter, which launched in March 2016. NOMAD consists of two infrared channels and one ultraviolet and visible channel, allowing the instrument to perform observations quasi-constantly, by taking nadir measurements at the day- and night-side, and during solar occultations. Here, in part 2 of a linked study, we describe the design, manufacturing, and testing of the ultraviolet and visible spectrometer channel called UVIS. We focus upon the optical design and working principle where two telescopes are coupled to a single grating spectrometer using a selector mechanism.

Autocorrelation and phase retrieval in the UV using two-photon absorption in diamond pin photodiodes.

We report on the utilization of the two-photon induced free carrier generation in a diamond pin-type photodiode to record fringe-resolved second-order autocorrelations of femtosecond pulses in the UV. Measurements in photovoltaic mode are performed at the second and third harmonic of a Ti:sapphire laser (lambda(0)=401 nm and lambda(0)=265 nm) with pulse energies down to about 2 nJ. The band gap of diamond of 5.5 eV sets a short wavelength limit at about 225 nm. Combined with the simultaneously recorded linear autocorrelation the spectral phase is reconstructed employing an iterative algorithm.