Aim
Our aim was to assess undiagnosed congenital heart defects (CHD) after newborns' hospital discharge in patients with a murmur or CHD suspicion, to find out the signs that predict CHDs and to ...estimate the costs of the examinations.
Methods
We reviewed retrospective medical records of patients (n = 490) referred for the evaluation of CHD suspicion during 2017–2018.
Results
The median age of the patients was 2.5 (IQR 0.5–7.4) years. Sixty‐three (13%) patients had an abnormal echocardiography. Neither ductal‐dependent nor cyanotic CHDs were found. Cardiac interventions were performed for 14 out of 63 (22%) patients. Clinical signs indicating CHDs were murmur grade ≥3 (10/11 91% vs. 53/479 11%, p < 0.001) and harsh murmur (15/44 34% vs. 48/446 11%, p < 0.001). Abnormal electrocardiography did not indicate CHD (8/40 20% vs. 55/447 12%, p = 0.165). The total cost of the examinations was 259 700€. The share of the cost of studies assessed as benign was 59%.
Conclusion
Only a few CHDs were found after newborn hospital discharge among patients who received foetal and newborn screening and were examined due to CHD suspicion. The high number of benign murmurs in children leads to many referrals, resulting in unnecessary healthcare costs.
Planck intermediate results Ade, P A R; Aghanim, N; Arnaud, M ...
Astronomy and astrophysics (Berlin),
1/2014, Letnik:
561
Journal Article
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Using Planck data combined with the Meta Catalogue of X-ray detected Clusters of galaxies (MC XC ), we address the study of peculiar motions by searching for evidence of the kinetic Sunyaev-Zeldovich ...effect (kSZ). By implementing various filters designed to extract the kSZ generated at the positions of the clusters, we obtain consistent constraints on the radial peculiar velocity average, root mean square (rms), and local bulk flow amplitude at different depths For the whole cluster sample of average redshift 0.18, the measured average radial peculiar velocity with respect to the cosmic microwave background (CMB) radiation at that redshift, i.e., the kSZ monopole, amounts to 72 + or - 60 km ssup -1. In this context, in conjunction with supernova observations, Planck is able to rule out a large class of inhomogeneous void models as alternatives to dark energy or modified gravity. The Planck constraints on peculiar velocities and bulk flows are thus consistent with the CDM scenario.
We describe the detection, interpretation, and removal of the signal resulting from interactions of high energy particles with the Planck High Frequency Instrument (HFI). There are two types of ...interactions: heating of the 0.1 K bolometer plate; and glitches in each detector time stream. The transientresponses to detector glitch shapes are not simple single-pole exponential decays and fall into three families. The glitch shape for each family has been characterized empirically in flight data and these shapes have been used to remove glitches from the detector time streams. The spectrum of the count rate per unit energy is computed for each family and a correspondence is made to the location on the detector of the particle hit. Most of the detected glitches are from Galactic protons incident on the die frame supporting the micro-machined bolometric detectors. In the Planck orbit at L2, the particle flux is around 5 cm-2 s-1 and is dominated by protons incident on the spacecraft with energy >39 MeV, at a rate of typically one event per second per detector. Different categories of glitches have different signatures in the time stream. Two of the glitch types have a low amplitude component that decays over nearly 1 s. This component produces excess noise if not properly removed from the time-ordered data. We have used a glitch detection and subtraction method based on the joint fit of population templates. The application of this novel glitch subtraction method removes excess noise from the time streams. Using realistic simulations, we find that this method does not introduce signal bias into the Planck data.
We present a system-level description of the Low Frequency Instrument (LFI) considered as a differencing polarimeter, and evaluate its expected performance. The LFI is one of the two instruments on ...board the ESA Planck mission to study the cosmic microwave background. It consists of a set of 22 radiometers sensitive to linear polarisation, arranged in orthogonally-oriented pairs connected to 11 feed horns operating at 30, 44 and 70 GHz. In our analysis, the generic Jones and Mueller-matrix formulations for polarimetry are adapted to the special case of the LFI. Laboratory measurements of flight components are combined with optical simulations of the telescope to investigate the values and uncertainties in the system parameters affecting polarisation response. Methods of correcting residual systematic errors are also briefly discussed. The LFI has beam-integrated polarisation efficiency >99% for all detectors, with uncertainties below 0.1%. Indirect assessment of polarisation position angles suggests that uncertainties are generally less than 0$\fdg$5, and this will be checked in flight using observations of the Crab nebula. Leakage of total intensity into the polarisation signal is generally well below the thermal noise level except for bright Galactic emission, where the dominant effect is likely to be spectral-dependent terms due to bandpass mismatch between the two detectors behind each feed, contributing typically 1–3% leakage of foreground total intensity. Comparable leakage from compact features occurs due to beam mismatch, but this averages to < 5 × 10-4 for large-scale emission. An inevitable feature of the LFI design is that the two components of the linear polarisation are recovered from elliptical beams which differ substantially in orientation. This distorts the recovered polarisation and its angular power spectrum, and several methods are being developed to correct the effect, both in the power spectrum and in the sky maps. The LFI will return a high-quality measurement of the CMB polarisation, limited mainly by thermal noise. To meet our aspiration of measuring polarisation at the 1% level, further analysis of flight and ground data is required. We are still researching the most effective techniques for correcting subtle artefacts in polarisation; in particular the correction of bandpass mismatch effects is a formidable challenge, as it requires multi-band analysis to estimate the spectral indices that control the leakage.
Objective: To establish normal values of left atrial and left ventricular volumes and function in children and young adults using three dimensional echocardiography (3DE). Methods: 169 healthy ...subjects aged 2 to 27 years were studied by digitised 3DE. 3DE was achieved using rotational acquisition of planes at 18° intervals from the parasternal view for the left atrium and from the transthoracic apical view for the left ventricle with ECG gating and without respiratory gating. Left atrial and left ventricular volumes could be calculated throughout the heart cycle, and the respective time–volume curves were reconstructed in each subject. Results: For the analysis the subjects were divided into five groups according to body surface area: 0.5–0.75 m2, 0.75–1.0 m2, 1.0–1.25 m2, 1.25–1.5 m2, and over 1.5 m2. Mean (SD) left atrial maximum volume/body surface area was 19.6 (3.5), 21.7 (3.7), 22.0 (4.7), 24.5 (4.8), and 27.4 (6.4) ml/m2; left ventricular maximum volume/body surface area was 50.1 (8.8), 54.9 (10.1), 56.4 (9.9), 58.7 (11.0), and 64.4 (10.3) ml/m2. Left atrial active emptying increased from 19% to 35% with age (r = 0.34, p < 0.001) and with decreasing heart rate (r = −0.28, p < 0.001). Conclusions: Transthoracic 3DE is well suited for studying the phasic changes in left atrial and left ventricular volumes in young children as well as in adults. The data obtained from 169 healthy subjects will serve as a reference for further studies in patients with various cardiac abnormalities.
The aims of this study were to establish normal values of left ventricular (LV) mass in children and young adults using three-dimensional echocardiography (3-DE) and to compare 3-DE LV mass estimates ...with those obtained by conventional echocardiographic methods. We studied 169 healthy subjects aged 2-27 years by digitized 3-D, two-dimensional (2-D), and M-mode echocardiography. 3-D echocardiography was performed by using rotational acquisition of planes at 18 degrees intervals from apical view with ECG gating and without respiratory gating. 3-DE gave smaller LV mass estimates than 2-DE and M-mode echocardiography (p < 0.001). Agreement analysis resulted in a bias of -9.3 +/- 36.5 g between 3-DE and 2-DE, and -18.5 +/- 47.9 g between 3-DE and M-mode. For the analysis, the subjects were divided into five groups according to body surface area (BSA): 0.5-0.75, 0.75-1.0, 1.0-1.25, 1.25-1.5, and greater than 1.5 m(2). LV mass/BSA by 3-DE was 45.6 (5.1), 54.3 (7.7), 55.2 (7.9), 58.8 (8.1), and 65.0 (9.9) g/m(2). LV mass/end diastolic volume (EDV) by 3-DE was 0.9 (0.1) g/ml in the BSA group of 0.5-0.75 m(2) and 1.0 (0.2) g/ml in the other BSA groups. LV mass increased linearly in relation to BSA, height, and body mass (r = 0.93, 0.90, and 0.92, respectively; p < 0.001 for all). The results showed a linear increase in LV mass, whereas LV mass/EDV ratio remained unchanged. However, LV mass estimates by 3-DE were lower than those obtained by 2-DE and M-mode echocardiography. The data obtained by 3-DE from 169 healthy subjects will serve as a reference for further studies in patients with various cardiac abnormalities.
Madam - a map-making method for CMB experiments Keihänen, E.; Kurki-Suonio, H.; Poutanen, T.
Monthly notices of the Royal Astronomical Society,
06/2005, Letnik:
360, Številka:
1
Journal Article
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We present a new map-making method for cosmic microwave background (CMB) measurements. The method is based on the destriping technique, but it also utilizes information about the noise spectrum. The ...low-frequency component of the instrument noise stream is modelled as a superposition of a set of simple base functions, whose amplitudes are determined by means of maximum-likelihood analysis, involving the covariance matrix of the amplitudes. We present simulation results with 1/f noise and show a reduction in the residual noise with respect to ordinary destriping. This study is related to Planck Low Frequency Instrument (LFI) activities.
MADAM is a CMB map-making code, designed to make temperature and polarization maps of time-ordered data of total power experiments like P LANCK. The algorithm is based on the destriping technique, ...but it also makes use of known noise properties in the form of a noise prior. The method in its early form was presented in an earlier work by Keihä nen et al. (2005, MNRAS, 360, 390). In this paper we present an update of the method, extended to non-averaged data, and include polarization. In this method the baseline length is a freely adjustable parameter, and destriping can be performed at a different map resolution than that of the final maps. We show results obtained with simulated data. This study is related to P LANCK LFI activities.
OBJECTIVE To assess the dynamic changes in left atrial volume by transthoracic three dimensional echocardiography and compare the results with those obtained by magnetic resonance imaging (MRI). ...DESIGN AND PATIENTS 30 healthy children (15 boys and 15 girls, aged 8 to 13 years) underwent examination by three dimensional echocardiography and MRI. METHODS Three dimensional echocardiography of the left atrium was performed using rotational acquisition of planes at 18° intervals from the parasternal window with ECG gating and without respiratory gating. Volume estimation by MRI was performed with a slice thickness of 4–8 mm and ECG triggering during breath holding in deep inspiration. A left atrial time–volume curve was reconstructed in each child. RESULTS Left atrial maximum and minimum volumes averaged 24.0 ml/m2 and 7.6 ml/m2 by three dimensional echocardiography, and 22.1 ml/m2 and 11.9 ml/m2 by MRI. The greater left atrial minimum volume in the latter was at least in part a result of breath holding. Dynamic changes in left atrial volume during the heart cycle were detectable by both methods. The higher temporal resolution of three dimensional echocardiography allowed a more precise evaluation of different phases. CONCLUSIONS Three dimensional echocardiography and MRI were both useful methods for studying the physiological volume changes in the left atrium in children. These methods may be used for further study of the systolic and diastolic function of the heart.
The destriping technique is a viable tool for removing different kinds of systematic effects in CMB-related experiments. It has already been proven to work for gain instabilities that produce the ...so-called $1/f$ noise and periodic fluctuations due to e.g. thermal instability. Both effects, when coupled to the observing strategy, result in stripes on the observed sky region. Here we present a maximum-likelihood approach to this type of technique and provide also a useful generalization. As a working case we consider a data set similar to what the planck satellite will produce in its Low Frequency Instrument (LFI). We compare our method to those presented in the literature and find some improvement in performance. Our approach is also more general and allows for different base functions to be used when fitting the systematic effect under consideration. We study the effect of increasing the number of these base functions on the quality of signal cleaning and reconstruction. This study is related to planck LFI activities.
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