Unmodelled magnetic contributions in satellite-based models

Additional file 6: Figure C4. Structure of the dependence of Swarm C dX residuals on IMF B y and B z according to the different IMF polarity sectors. Colour scale is given in arbitrary units (a.u.)

Statistical analysis of geomagnetic field intensity differences between ASM and VFM instruments onboard Swarm constellation

From the very first measurements made by the magnetometers onboard Swarm satellites launched by European Space Agency (ESA) in late 2013, it emerged a discrepancy between scalar and vector measurements. An accurate analysis of this phenomenon brought to build an empirical model of the disturbance, highly correlated with the Sun incidence angle, and to correct vector data accordingly. The empirical model adopted by ESA results in a significant decrease in the amplitude of the disturbance affecting VFM measurements so greatly improving the vector magnetic data quality. This study is focused on the characterization of the difference between magnetic field intensity measured by the absolute scalar magnetometer (ASM) and that reconstructed using the vector field magnetometer (VFM) installed on Swarm constellation. Applying empirical mode decomposition method, we find the intrinsic mode functions (IMFs) associated with ASM–VFM total intensity differences obtained with data both uncorrected and corrected for the disturbance correlated with the Sun incidence angle. Surprisingly, no differences are found in the nature of the IMFs embedded in the analyzed signals, being these IMFs characterized by the same dominant periodicities before and after correction. The effect of correction manifests in the decrease in the energy associated with some IMFs contributing to corrected data. Some IMFs identified by analyzing the ASM–VFM intensity discrepancy are characterized by the same dominant periodicities of those obtained by analyzing the temperature fluctuations of the VFM electronic unit. Thus, the disturbance correlated with the Sun incidence angle could be still present in the corrected magnetic data. Furthermore, the ASM–VFM total intensity difference and the VFM electronic unit temperature display a maximal shared information with a time delay that depends on local time. Taken together, these findings may help to relate the features of the observed VFM–ASM total intensity difference to the physical characteristics of the real disturbance thus contributing to improve the empirical model proposed for the correction of data

Observations of high-latitude geomagnetic field fluctuations during St. Patrick's Day storm: Swarm and SuperDARN measurements

The aim of this work is to study the properties of the magnetic field's fluctuations produced by ionospheric and magnetospheric electric currents during the St. Patrick's Day geomagnetic storm (17 March 2015). We analyse the scaling features of the external contribution to the horizontal geomagnetic field recorded simultaneously by the three satellites of the Swarm constellation during a period of 13 days (13–25 March 2015). We examine the different latitudinal structure of the geomagnetic field fluctuations and analyse the dynamical changes in the magnetic field scaling features during the development of the geomagnetic storm. Analysis reveals consistent patterns in the scaling properties of magnetic fluctuations and striking changes between the situation before the storm, during the main phase and recovery phase. We discuss these dynamical changes in relation to those of the overall ionospheric polar convection and potential structures as reconstructed using SuperDARN data. Our findings suggest that distinct turbulent regimes characterised the mesoscale magnetic field's fluctuations and that some factors, which are known to influence large-scale fluctuations, have also an influence on mesoscale fluctuations. The obtained results are an example of the capability of geomagnetic field fluctuations data to provide new insights about ionospheric dynamics and ionosphere–magnetosphere coupling. At the same time, these results could open doors for development of new applications where the dynamical changes in the scaling features of the magnetic fluctuations are used as local indicators of magnetospheric conditions

Detecting geomagnetic field nonlinearities by bispectral analysis and a phase coupling nonlinear technique

The Earth's magnetic field varies over a wide range of characteristic times, say, from years to centuries, and more. In order to detect some nonlinear features of the geomagnetic field evolution we first apply a nonlinear spectral technique, i.e. bispectral analysis, to the secular variation of Hartland Geomagnetic Observatory (U.K.). Then, due to difficulties of bispectral analysis inherent in the shortness of data, we introduce a simpler, but more efficient, technique called Spectral Phase Analysis for Quadratic Coupling Estimation (SPAQCE). Both nonlinear spectral methods here applied are based on the presence of a phase (sum and difference) coupling in case of quadratic interactions between two constituent components of the physical system underlying the generation of the geomagnetic field. The application of SPAQCE to annual means of a UK combined geomagnetic time series allows us to discriminate nonlinear interactions between couples of characteristic times (specifically 5-6, 5-8 and 2-26 years) of the field generated in the outer core

Comparison between IRI and preliminary Swarm Langmuir probe measurements during the St. Patrick storm period

Preliminary Swarm Langmuir probe measurements recorded during March 2015, a period of time including the St. Patrick storm, are considered. Specifically, six time periods are identified: two quiet periods before the onset of the storm, two periods including the main phase of the storm, and two periods during the recovery phase of the storm. Swarm electron density values are then compared with the corresponding output given by the International Reference Ionosphere (IRI) model, according to its three different options for modelling the topside ionosphere. Since the Swarm electron density measurements are still undergoing a thorough validation, a comparison with IRI in terms of absolute values would have not been appropriate. Hence, the similarity of trends embedded in the Swarm and IRI time series is investigated in terms of Pearson correlation coefficient. The analysis shows that the electron density representations made by Swarm and IRI are different for both quiet and disturbed periods, independently of the chosen topside model option. Main differences between trends modelled by IRI and those observed by Swarm emerge, especially at equatorial latitudes, and at northern high latitudes, during the main and recovery phases of the storm. Moreover, very low values of electron density, even lower than 2 × 10^4 cm−3, were simultaneously recorded in the evening sector by Swarm satellites at equatorial latitudes during quiet periods, and at magnetic latitudes of about ±60° during disturbed periods. The obtained results are an example of the capability of Swarm data to generate an additional valuable dataset to properly model the topside ionosphere

ADJUNTOS MODAIS DE TEXTOS LITERÁRIOS EM RELAÇÃO DE TRADUÇÃO

Este artigo tem por objetivo analisar os Adjuntos Modais (HALLIDAY, 1994) no conto “A pair of silk stockings” de Kate Chopin (1994) e em duas de suas traduções para o português brasileiro, uma feita por Márcia Knop (CHOPIN, 2011) e a outra por Henrique Vieira Tozzi (CHOPIN, 2017). O corpus foi anotado com categorias de Adjuntos Modais que, por sua vez, foram quantificadas no programa computacional WordSmith Tools. Resultados apontam que os Adjuntos Modais de Modo Oracional são mais frequentes que os Adjuntos Modais de Comentário nos textos literários em relação de tradução. Resultados também apontam que o número de Adjuntos Modais de Modo Oracional é maior nas traduções em comparação ao original. Pode-se concluir que Tozzi apresenta uma forte tendência de tematizar Adjuntos Modais, o que não ocorre tão frequentemente com Knop

Improving Childbirth and Maternal Care - How to Foster the Use of Good Practices for Patient Safety

Despite the global effort toward improving childbirth and maternity care, there are still complications (hemorrhage, infections, and high blood pressure) that may arise unexpectedly. To end preventable mortality, every woman needs skilled care at birth. The aim of this chapter is to present some solutions implemented by Frontline professionals and healthcare organizations made available through the Italian Observatory on Good Practices for Patient Safety, a national program to improve patient safety by promoting diffusion and active dissemination of evidence-based practices

Investigation of the Physical Processes Involved in GNSS Amplitude Scintillations at High Latitude: A Case Study

The storm onset on 7 September 2017, triggered several variations in the ionospheric electron density, causing severe phase fluctuations at polar latitudes in both hemispheres. In addition, although quite rare at high latitudes, clear amplitude scintillations were recorded by two Global Navigation Satellite System receivers during the main phase of the storm. This work attempted to investigate the physical mechanisms triggering the observed amplitude scintillations, with the aim of identifying the conditions favoring such events. We investigated the ionospheric background and other conditions that prevailed when the irregularities formed and moved, following a multi-observations approach. Specifically, we combined information from scintillation parameters and recorded by multi-constellation (GPS, GLONASS and Galileo) receivers located at Concordia station (75.10°S, 123.35°E) and SANAE IV base (71.67°S, 2.84°W), with measurements acquired by the Special Sensor Ultraviolet Spectrographic Imager on board the Defense Meteorological Satellite Program satellites, the Super Dual Auroral Radar Network, the Swarm constellation and ground-based magnetometers. Besides confirming the high degree of complexity of the ionospheric dynamics, our multi-instrument observation identified the physical conditions that likely favor the occurrence of amplitude scintillations at high latitudes. Results suggest that the necessary conditions for the observation of this type of scintillation in high-latitude regions are high levels of ionization and a strong variability of plasma dynamics. Both of these conditions are typically featured during high solar activity

Using social robot NAO for emotional support to children at a paediatric emergency department: a randomised clinical trial

Background: Social robots have been used for improving anxiety in children in stressful clinical situations, as during painful procedures. No studies have been performed yet to assess their effect in children while waiting for emergency room consultations. Objective: To assess the impact of social robots in managing stress in children waiting for an emergency room procedure through the assessment of salivary cortisol levels. Methods: This was an open randomised clinical trial in children attending a paediatric emergency department. Children accessing the emergency room were randomised to one of three groups: 1) playing with a NAO social robot; 2) playing with a study nurse; 3) waiting with parents. All children were measured salivary cortisol levels through a swab. Salivary cortisol levels before and after the intervention were compared in the three groups. We calculated the effect size of our interventions through the Cohen's d-based effect size correlation (r). Results: A total of 109 children aged 3 to 10 years were enrolled in the study and 94 had complete data for the analyses. Salivary cortisol levels decreased significantly more in the group exposed to robot interaction than in the other two groups (r=0.75). Cortisol levels decreased more in girls (r=0.92) than boys (r=0.57). Conclusions: Social robots are efficacious in decreasing stress in children accessing the emergency room and may be considered as a tool for improving emotional perceptions of children and their families in such a critical setting. Clinicaltrial: Robot Therapy in Pediatric Emergency, NCT04627909, https://clinicaltrials.gov/ct2/show/study/NCT04627909

ITalian Geomagnetic Reference Field (ITGRF): update for 2000 and secular variation model up to 2005 by autoregressive forecasting

The updated version of the ITalian Geomagnetic Reference Field (ITGRF) for 2000.0 and its secular variation model up to 2005.0 are presented in this paper. The main field model is based on a simple polynomial approximation in latitude and longitude of the geomagnetic field elements computed from IGRF on a 12° ¥ 11° grid centred over Italy. The annual means from L'Aquila observatory were used to determine the baseline level, imposing a constant observatory anomaly bias. This procedure gives a set of 6 coefficients every 5 years from 1960 to 2005 for the horizontal H, total field F, vertical Z and declination D elements of the geomagnetic field. The extrapolation of ITGRF to 2005 is based on an autoregressive forecasting of the L'Aquila observatory annual means. Comparison of the field values computed from the model with those recorded at the other Italian observatory (Castello Tesino) shows that the ITGRF improves the fit of the secular variation pattern with respect to the global IGRF model by a factor of 3. The ITGRF represents a reliable alternative to global models when reducing magnetic surveys to a common reference epoch over the Italian region