Improvements and validation of the IRI UP method under moderate, strong, and severe geomagnetic storms

This work describes several important improvements made to the International Reference Ionosphere UPdate (IRI UP) method, and a careful validation of its performances under disturbed conditions. The IRI UP method has been improved developing an algorithm capable to properly filter wrongly autoscaled ionosonde data to be assimilated, avoiding the use of these in the assimilation process. Furthermore, the preliminary quality check used to choose the variogram model in the Universal Kriging method has been replaced with a new quality check routine (NQCR), based on statistical tests carried out using the variables Q1, Q2, and cR, built on variogram's residuals. NQCR objectively identifies the best variogram model from which to get more reliable effective indices maps to be ingested in the IRI model to obtain updated foF2 and hmF2 maps. IRI UP has been applied on 30 different time intervals, between January 1, 2004, and December 31, 2016, characterized by moderate, strong, and severe geomagnetic conditions, over the European region. A statistical comparison between IRI UP and IRI at the truth sites located at Fairford (51.7°N, 1.5°W, UK) and San Vito (40.6°N, 17.8°E, Italy), for foF2 and hmF2, has been performed. From the statistical validation clearly emerges how IRI UP, for foF2, performs significantly better than IRI, for each of the 30 geomagnetic storms considered. Regarding hmF2, IRI UP performances are lower than those for foF2, although still better than IRI ones. In the light of the results achieved in this investigation, the IRI UP method represents an interesting approach to Space Weather forecast in the ionospheric domain. Open image in new windo

Cross Cultural Adaptation and Validation of Italian Version of the Leeds Assessment of Neuropathic Symptoms and Signs Scale and Pain DETECT Questionnaire for the Distinction between Nociceptive and Neuropathic Pain

Objective. This study aimed to validate Italian versions of Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) scale and Pain DETECT questionnaire (PD-Q) and evaluate the ability of these questionnaires to discriminate between nociceptive and neuropathic pain. Design. Multicenter prospective validation cohort study. Subjects and Setting. One hundred patients were included with a diagnosis formulated by a specialist in outpatient settings (50 affected by knee osteoarthritis as nociceptive pain and 50 affected by trigeminal or postherpetic neuralgia as neuropathic pain). Methods. The Italian versions of both questionnaires according to Italian cultural characteristics were performed according to the following steps: (1) translation of the questionnaires from English into Italian; (2) review by a bilingual individual for consistency; (3) proposed version after a mail round between experts; (4) backward translation; (5) comparison with the original English version by the experts; (6) approved version of the questionnaires. One hundred patients were enrolled and completed the two questionnaires administered by a specialist or blinded nursing staff, at the baseline and after 24/48 hours. Internal consistency, stability, validity, and discriminative power were analyzed. Results. Statistically significant differences were reported about the ability of both questionnaires to discriminate between patients affected by neuropathic or nociceptive pain. Internal consistency for the Italian version of the LANSS was 0.76, and for PD-Q, it was 0.80, assessed by Cronbach’s α; LANSS showed a good test-retest reliability with an ICC of 0.76, and PD-Q showed a high test-retest reliability with an ICC of 0.96. For interrater reliability, there was a concordance rate of 83.3% between reference diagnosis and LANSS (Cohen’s kappa = 0.67, CI 95% 0.52–0.75). Conclusions. This study validated the Italian versions of LANSS and PD-Q as reliable instruments with good psychometric characteristics, for pain evaluation, discriminating between nociceptive and neuropathic pain. Our findings were similar to those observed in the original study. Furthermore, we have reported the test-retest reliability for both questionnaires, not addressed in original validation studies

Towards a Real-Time Description of the Ionosphere: A Comparison between International Reference Ionosphere (IRI) and IRI Real-Time Assimilative Mapping (IRTAM) Models

This paper focuses on a detailed comparison, based on the F2-layer peak characteristics foF2 and hmF2, between the International Reference Ionosphere (IRI), which is a climatological empirical model of the terrestrial ionosphere, and the IRI Real-Time Assimilative Mapping (IRTAM) procedure, which is a real-time version of IRI based on data assimilation from a global network of ionosondes. To perform such a comparison, two different kinds of datasets have been considered: (1) foF2 and hmF2 as recorded by 40 ground-based ionosondes spread all over the world from 2000 to 2019; (2) foF2 and hmF2 from space-based COSMIC/FORMOSAT-3 radio occultation measurements recorded from 2006 to 2018. The aim of the paper is to understand whether and how much IRTAM improves IRI foF2 and hmF2 outputs for different locations and under different diurnal, seasonal, solar and magnetic activity conditions. The main outcomes of the study are: (1) when ionosonde observations are considered for validation, IRTAM significantly improves the IRI foF2 modeling both in accuracy and precision, while a slight improvement in the IRI hmF2 modeling is observed for specific locations and conditions; (2) when COSMIC observations are considered for validation, no noticeable improvement is observed from the IRTAM side for both foF2 and hmF2. Indeed, IRTAM can improve the IRI foF2 description only nearby the assimilated ionosonde locations, while the IRI hmF2 description is always more accurate and precise than IRTAM one

On the influence of solar activity on the mid-latitude sporadic E layer

To investigate the influence of solar cycle variability on the sporadic E layer (Es), hourly measurements of the critical frequency of the Es ordinary mode of propagation, foEs, and of the blanketing frequency of the Es layer, fbEs, recorded from January 1976 to December 2009 at the Rome (Italy) ionospheric station (41.8° N, 12.5° E), were examined. The results are: (1) a high positive correlation between the F10.7 solar index and foEs as well as between F10.7 and fbEs, both for the whole data set and for each solar cycle separately, the correlation between F10.7 and fbEs being much higher than the one between F10.7 and foEs; (2) a decreasing long-term trend of the F10.7, foEs and fbEs time series, with foEs decreasing more rapidly than F10.7 and fbEs; (3) clear and statistically significant peaks at 11 years in the foEs and fbEs time series, inferred from Lomb-Scargle periodograms

On the solar cycle dependence of the amplitude modulation characterizing the mid-latitude sporadic E layer diurnal periodicity

Spectral analyses are employed to investigate how the diurnal periodicity of the critical frequency of the sporadic E (Es) layer varies with solar activity. The study is based on ionograms recorded at the ionospheric station of Rome (41.8\ub0N, 12.5\ub0E), Italy, from 1976 to 2009, a period of time covering three solar cycles. It was confirmed that the diurnal periodicity is always affected by an amplitude modulation with periods of several days, which is the proof that Es layers are affected indirectly by planetary waves through their nonlinear interaction with atmospheric tides at lower altitudes. The most striking features coming out from this study is however that this amplitude modulation is greater for high-solar activity than for low-solar activity

An Update of the NeQuick-Corr Topside Ionosphere Modeling Based on New Datasets

A new analytical formula for H0, one of the three parameters (H0, g, and r) on which the NeQuick model is based to describe the altitude profile of the electron density above the F2-layer peak height hmF2, has recently been proposed. This new analytical representation of H0, called H0,corr, relies on numerical grids based on two different types of datasets. On one side, electron density observations by the Swarm satellites over Europe from December 2013 to September 2018, and on the other side, IRI UP (International Reference Ionosphere UPdate) maps over Europe of the critical frequency of the ordinary mode of propagation associated with the F2 layer, foF2, and hmF2, at 15 min cadence for the same period. The new NeQuick topside representation based on H0,corr, hereafter referred to as NeQuick-corr, improved the original NeQuick topside representation. This work updates the numerical grids of H0,corr by extending the underlying Swarm and IRI UP datasets until December 2021, thus allowing coverage of low solar activity levels, as well. Moreover, concerning Swarm, besides the original dataset, the calibrated one is considered, and corresponding grids of H0,corr calculated. At the same time, the role of g is investigated, by considering values different from the reference one, equal to 0.125, currently adopted. To understand what are the best H0,corr grids to be considered for the NeQuick-corr topside representation, vertical total electron content data for low, middle, and high latitudes, recorded from five low-Earth-orbit satellite missions (COSMIC/FORMOSAT-3, GRACE, METOP, TerraSAR-X, and Swarm) have been analyzed. The updated H0,corr grids based on the original Swarm dataset with a value for g = 0.15, and the updated H0,corr grids based on the calibrated Swarm dataset with a value for g = 0.14, are those for which the best results are obtained. The results show that the performance of the different NeQuick-corr models is reliable also for low latitudes, even though these are outside the spatial domain for which the H0,corr grids were obtained, and are dependent on solar activity

The instruments used by the Italian centres for cognitive disorders and dementia to diagnose mild cognitive impairment (MCI)

Aims: The purpose of this study was to examine the tools used in Italy to diagnose mild cognitive impairment (MCI). Methods: In collaboration with the Luigi Amaducci Research Consortium, the Italian Network of Alzheimer Evaluation Units prepared a questionnaire to describe how MCI is diagnosed in the Italian Centres for cognitive disorders and dementia (CCDD). Results: Most of the ninety-two CCDDs participating in the survey were located in hospitals (54.7%); large percentages were coordinated by neurologists (50.8%) and geriatricians (44.6%). Almost all (98.5%) used the Mini Mental State Examination to diagnose MCI; the Clock Drawing Test was also frequently used (83.9%). Other neuropsychological, imaging and biomarker tests were utilized less frequently and a wide diversity in the instruments used was noted. Conclusions: According to the results, diagnoses of MCI are based on a multitude of instruments, with major differences in the clinical assessment of geriatricians and neurologists. Standardized testing protocols, validated instruments and cut-off points need to be identified and adopted by the CCDDs for assessing MCI