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Ionospheric irregularities may affect electromagnetic signals propagating through the ionosphere and consequently contribute to the malfunctioning of the Global Navigation Satellite Systems hindering their accuracy and reliability. In this study, we use data recorded on board two of the three satellites of the Swarm constellation (namely, Swarm A and Swarm B) from 15 July 2014 to 31 December 2021 to assess the possible dependence of the Global Positioning System (GPS) signals loss of lock on the presence of a specific kind of ionospheric irregularities. To accomplish this task we study the scaling features of the electron density fluctuations through the structure function analysis simultaneously to the occurrence of loss of lock events through measurements recorded by the Langmuir probes and the precise orbit determination antennas on board Swarm A and Swarm B satellites. We find that the plasma density irregularities in a turbulent state characterized by intermittent structures and extremely high values of the Rate Of change of electron Density Index can lead to GPS loss of lock events. This is always true at mid and high latitudes, especially inside the auroral oval. In the equatorial belt, this happens in at least 75% of identified GPS loss of lock events that basically coincide with the occurrence of plasma bubbles. Plain Language Summary: One of the natural factors that most contributes to the malfunctioning of Global Navigation Satellite Systems and leads to a degradation of their performance, accuracy and reliability, is represented by ionospheric irregularities. In this work, using data recorded by the European Space Agency Swarm constellation mission, we show for the first time that turbulence and extremely high values of the Rate Of change of electron Density Index are at the base of those ionospheric irregularities responsible for Global Positioning System loss of lock events. This result represents an important step forward in the perspective of developing a prediction model of such events, which could be significant in the framework of Space Weather purposes. Key Points: Global Positioning System (GPS) loss of lock events are discussed according to the dynamical status of the ionosphereIonospheric irregularities at the base of the GPS loss of lock events present an intermittent turbulent natureExtremely high values of Rate Of change of electron Density Index are associated with GPS loss of lock events [ABSTRACT FROM AUTHOR]

We have analyzed a highly monochromatic (f = 1.67 mHz) and large‐amplitude Ultra Low Frequency (ULF) wave event observed at satellites and ground observatories on 23 June 2020 during super solar quiet geomagnetic conditions. The train wave was detected between 6:22 and 7:55 UT across a wide longitudinal range of ground stations from low to high latitudes. Using Deep Space Climate Observatory and THEMIS‐B spacecraft, which were in the interplanetary medium, we have identified the possible driver of such global ULF wave activity in the impact of a small pressure pulse accompanied by a discontinuity in the magnetic field. The prolonged duration (90 min) of the ULF waves as well as their latitude‐independent frequency and the small azimuthal wave number (m ∼ 0−2) can be explained in terms of a global magnetospheric waveguide mode. The amplitude and cross‐phase analysis of the wave activity at ground, together with the polarization pattern, suggest the waveguide mode coupling with field line resonance. Nevertheless, during the same time interval, indirect evidence exists of a rapid reconfiguration of the magnetotail in the form of Pi2 waves in the night‐side region. The analysis of energetic particle flux at ionospheric height (500 km) shows a direct connection between the ULF wave activity and particle precipitation. Plain Language Summary: Ultra Low Frequency (ULF) waves illustrates the highly dynamical nature of the Earth's magnetosphere since they are directly connected with energy and mass transport. The event we analyzed occurred during a very low geomagnetic activity showing 10 min period (Pc5) waves between 6:22 and 7:55 UT across a wide longitudinal range of ground stations from low to high latitudes that lead to particle precipitation. The prolonged duration (90 min) of the ULF waves as well as their latitude‐independent frequency and the small azimuthal wave number can be explained in terms of a global magnetospheric waveguide mode. The latitude and local time polarization pattern of the Pc5 wave event, suggests the waveguide mode coupling with magnetospheric field line resonances. The satellite observations in the interplanetary medium suggest that small solar wind disturbances were able to trigger the dynamic of the system directly, with Pc5 waves in response to the impact of a small jump in dynamic pressure, and indirectly, together with a rotation of the interplanetary magnetic field, triggering magnetotail processes resulting in an additional higher frequency wave activity (Pi2). Such kind of studies need scrupulous attention when trying to identify the possible source of ULF wave activity. Key Points: Global magnetospheric anomalous Ultra Low Frequency waves activity during super solar quiet conditionsCoupling between the waveguide mode and magnetospheric field line resonanceSignatures of particle precipitation at Low Earth Orbit orbit during Pc5 and Pi2 wave activity [ABSTRACT FROM AUTHOR]

An analysis of noise attenuation during 80 solar flares between 2013 and 2017 was carried out at frequencies 8–20 MHz using 34 Super Dual Auroral Radar Network radars and the EKB ISTP SB RAS radar. The attenuation was determined on the basis of noise measurements performed by the radars during the intervals between transmitting periods. The location of the primary contributing ground sources of noise was found by consideration of the propagation paths of radar backscatter from the ground. The elevation angle for the ground echoes was determined through a new empirical model. It was used to determine the paths of the noise and the location of its source. The method was particularly well suited for daytime situations, which had to be limited for the most part to only two crossings through the D region. Knowing the radio path was used to determine an equivalent vertical propagation attenuation factor. The change in the noise during solar flares was correlated with solar radiation lines measured by GOES/XRS, GOES/EUVS, SDO/AIA, SDO/EVE, SOHO/SEM, and PROBA2/LYRA instruments. Radiation in the 1 to 8 Å and near 100 Å are shown to be primarily responsible for the increase in the radionoise absorption, and by inference, for an increase in the D and E region density. The data are also shown to be consistent with a radar frequency dependence having a power law with an exponent of −1.6. This study shows that a new data set can be made available to study D and E regions. Key Points: HF noise attenuation in the ionosphere was investigated with 35 radars during 80 X‐ray solar flaresThe evolution of HF noise attenuation following an X‐ray solar flare is explained by a linear combination of 1‐ to 8‐ and 94‐Å solar radiationThe experimental frequency dependence of the absorption at 8–20 MHz is A[dB]∼f−1.6 [ABSTRACT FROM AUTHOR]

A Post-Authorization Safety Study (PASS) global program was designed to assess safety and effectiveness of rAHF-PFM (ADVATE) use in haemophilia patients in routine clinical settings. The main aim of this project was to estimate the rate of inhibitors and other adverse events across ADVATEPASS studies by meta-analysing individual patient data (IPD). Eligible Studies: PASS studies conducted in different countries, between 2003 and 2013, for which IPD were provided. Eligible patients: haemophilia A patients with baseline FVIII:C < 5%, with a known number of prior exposure days (EDs). Primary outcome: de novo inhibitors in severe, previously treated patients (PTPs) with > 150 EDs. Secondary outcomes: de novo inhibitors according to prior exposure and disease severity; other adverse events; annualized bleeding rate (ABR). Analysis: randomeffects logistic regression. Five of seven registered ADVATE-PASS (Australia, Europe, Japan, Italy and USA) and 1188 patients were included (median followup 384 days). Among severe PTPs with > 150 EDs, 1/ 669 developed de novo inhibitors (1.5 per 1000; 95% confidence interval [CI] 0.2, 10.6 per 1000). Among all patients included in the PASS studies, 21 developed any type of inhibitors (2.0%, 95% CI: 0.8%, 4.7%). Less than 1% of patients presented with other serious adverse events possibly related to ADVATE. The overall median ABR was 3.83 bleeds/year (first, third quartiles: 0.60, 12.90); 1.66 (0, 4.78) in the 557 patients continuously on prophylaxis ≥ twice/week. Metaanalysing PASS data from different countries confirmed the overall favourable safety and effectiveness profile of ADVATE in routine clinical settings. [ABSTRACT FROM AUTHOR]

Objective The aim of the study was to explore the association of dementia with in-hospital death in acutely ill medical patients. Methods Thirty-four internal medicine and 4 geriatric wards in Italy participated in the Registro Politerapie SIMI-REPOSI-study during 2008. One thousand three hundred and thirty two in-patients aged 65 years or older were enrolled. Logistic regression models were used to evaluate the association of dementia with in-hospital death. Socio-demographic characteristics, morbidity (single diseases and the Charlson Index), number of drugs, and adverse clinical events during hospitalization were considered as potential confounders. Results One hundred and seventeen participants were diagnosed as being affected by dementia. Patients with dementia were more likely to be women, older, to have cerebrovascular diseases, pneumonia, and a higher number of adverse clinical events during hospitalization. The percentage of patients affected by dementia who died during hospitalization was higher than that of patients without dementia (9.4 versus 4.9%). After multiadjustment, the diagnosis of dementia was associated with in-hospital death (OR = 2.1; 95% CI = 1.0-4.5). Having dementia and at least one adverse clinical event during hospitalization showed an additive effect on in-hospital mortality (OR = 20.7; 95% CI = 6.9-61.9). Conclusions Acutely ill elderly patients affected by dementia are more likely to die shortly after hospital admission. Having dementia and adverse clinical events during hospital stay increases the risk of death. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

When the disease is rare and/or the outcome is uncommon the trial design does not warrant precise and unbiased estimates due to a lack of power or the expected length of recruitment and observation periods. Is there any reliable method to control for bias and consequently achieve an advantage from estimates generated by different study designs? An interesting statistical approach suitable to solve this problem has been theorized by Thomas Bayes. A Bayesian analysis is aimed at answering the question ‘How this trial will modify our belief about that treatment effect?’ In summary, the Bayesian approach can be defined as the explicit and quantitative use of any kind of external evidence in the design, analysis, and interpretation of an experimental trial. The results of a Bayesian analysis is the 95% credible interval in which we believe the estimate to lie with a probability of 95%, or the estimate of the probability that the quantity of interest is less than a specific value. The principal advantages of the Bayesian approach are that it allows to directly make probability statements about quantities of interest; it allows to easily make predictive statements, conditional on the current state of knowledge; it enables evidence from a variety of sources to be taken into account within a coherent modelling framework; it requires the investigator to explicit prior beliefs and demands. Exemplifications of the advantages of the Bayesian approach will be given discussing some papers published in Haemophilia. [ABSTRACT FROM AUTHOR]

The risk of recurrence after discontinuation of anticoagulation for a combined oral contraceptive (COC)-associated venous thromboembolism (VTE) is unclear. Therefore, we conducted a systematic review and meta-analysis to estimate the incidence of recurrent VTE among women with COC-associated VTE, unprovoked VTE and to compare the incidence of recurrent VTE between the two groups. The Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Embase Classic +Embase and Medline ALL to July 2020 and citations from included studies were searched. Randomized controlled trials, prospective cohort studies and meta-analyses of these study types were selected. The analysis was conducted by random-effects model. Nineteen studies were identified including 1537 women [5828 person-years (PY)] with COC-associated VTE and 1974 women (7798 PY) with unprovoked VTE. Studies were at low risk of bias. The incidence rate of VTE recurrence was 1.22/100 PY [95% confidence interval (CI) 0.92-1.62, I 2  = 6%] in women with COC-associated VTE, 3.89/100 PY (95% CI 2.93-5.17, I 2  = 74%) in women with unprovoked VTE and the unadjusted incidence rate ratio was 0.34 (95% CI 0.26-0.46, I 2  = 3%). The recurrence risk in women after COC-associated VTE is low and lower than after an unprovoked VTE., (© 2022 British Society for Haematology and John Wiley & Sons Ltd.)

Background: To evaluate HIV infection-induced alterations in the oral mucosa by comparing inflammation, cell maturation, and cytomorphometric changes in oral mucosal cells between HIV-infected patients undergoing highly active antiretroviral therapy (HAART) and non-HIV-infected patients., Methods: Thirty HIV-infected patients undergoing HAART and 30 non-HIV-infected patients were studied. Four smears were obtained from the lateral border of the tongue and floor of the mouth with a cytobrush. One sample was stained by the Papanicolaou technique, and three samples were processed for Feulgen staining. Papanicolaou-stained smears were analyzed by light microscopy, and the cytoplasmic (CA) and nuclear (NA) area were measured with the Software AxioVision 4.7., Results: The Wilcoxon signed-rank test showed a significant difference in intermediate epithelial cell types between the HIV-infected and non-HIV-infected groups (P=.005). However, this difference was not observed for superficial epithelial cell types with (P=.672) and without a nucleus (P=.069). Comparative analysis revealed no significant difference in CA (P=.604), NA (P=.298) or NA/CA (P=.456) between the HIV-infected and non-HIV-infected groups. Keratohyalin granules were more frequent in the non-HIV-infected group (P=.0001)., Conclusions: The results showed alterations in cell maturation in HIV-infected patients undergoing HAART with undetectable viral load, but no morphometric changes were observed., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: The genotoxic impact of HIV infection on the oral cavity malignancies is unknown. The aim of this study was to evaluate the effect of HIV infection in micronucleus (MN) frequency on the oral mucosa of HIV+ patients and establish a relationship with early cytogenetic changes in oral carcinogenesis., Methods: Thirty HIV+ individuals who are under highly active antiretroviral therapy (HAART) and 30 non-HIV patients were evaluated. Two smears were taken from the lateral border of the tongue and mouth floor and stained by Feulgen. The frequency of MN was examined in 3000 cells per subject under common microscopy., Results: MN analysis showed no significant difference between groups by Mann-Whitney U-test for total MNs (P = 0.178). The presence of single MN was greater in control group with statistical significance (P = 0.009), while in HIV group, multiple MNs were exhibited in higher mean., Conclusions: HIV patients under HAART therapy and low viral load values showed higher frequency of multiple MNs, which, although not statistically significant, may be caused by the action of the Vpr gene, an accessory gene of HIV. These results corroborate the theory of HIV infection cytogenetic damage., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

This report presents a new use for rehabilitation protocol for oral sinus communications in patients with antiresorptive agent-induced osteonecrosis of the jaw. The treatment plan consisted of constructing an atraumatic complete denture with rounded edges, made with nontoxic resin, to prevent any injury to the mucosa and recurrence of the disease. The patient was followed up for 4 years, without any complications, and was socially reintegrated by resuming the normal life he experienced before tooth loss., (© 2014 by the American College of Prosthodontists.)