Proposed satellite position determination systems and techniques for Geostationary Synthetic Aperture Radar

This paper proposes two different calibration techniques for Geostationary Synthetic Aperture Radar (GEOSAR) missions requiring a high precision positioning, based on Active Radar Calibrators and Ground Based Interferometry. The research is enclosed in the preparation studies of a future GEOSAR mission providing continuous monitoring at continental scale.Peer ReviewedPostprint (author's final draft

Structural integrity assessment of a nuclear vessel through ASME and master curve approaches using irradiation embrittlement predictions

ABSTRACT: The assessment of the structural integrity of nuclear vessels is based on a series of procedures developed in the 1970s and 1980s. On one hand, curves that, according to the American Society of Mechanical Engineers code, describe the relationship between steel toughness and temperature in the ductile-to-brittle transition region, based on the reference temperature concept RTNDT, were adopted in 1972. On the other hand, the material embrittlement derived from the exposure of steel to neutron irradiation is determined through the model included in “Regulatory Guide 1.99 Rev. 2,” published in 1988. Since then, there have been enormous advances in this field. For example, the Master Curve, based on the reference temperature T0, describes the relationship between toughness and temperature in the transition zone more realistically and with much more robust microstructural and mechanical foundations and uses the elastic-plastic fracture toughness KJc. Moreover, improved models have been developed to estimate the embrittlement of steel subjected to neutron irradiation, such as ASTM E900, Standard Guide for Predicting Radiation-Induced Transition Temperature Shift in Reactor Vessel Materials. This study is aimed at comparing the results obtained using traditional procedures to the improved alternatives developed later. For this purpose, the behavior of the steel of a nuclear vessel that is currently under construction has been experimentally characterized through RTNDT and T0 parameters. In addition, the material embrittlement has been quantified using “Regulatory Guide 1.99 Rev. 2” and ASTM E900. These experimental results have been transferred to the assessment of the structural integrity of the vessel to determine the pressure-temperature limit curves and size of the maximum admissible defect as a function of the operation time of the plant. The results have allowed the implicit overconservatism present in the traditional procedures to be quantified.This project was carried out with the financial support of Sociedad para el Desarrollo Regional de Cantabria (SODERCAN) and Equipos Nucleares S.A. (ENSA), to whom the authors would like to express their gratitude

Potential Impact of Mepolizumab in Stepping Down Anti-Osteporotic Treatment in Corticosteroid-Dependent Asthma

Oral corticosteroids (OCS) are commonly used for the acute management of severe asthma exacerbations or as maintenance therapy; however, chronic use is associated with significant toxicities, e.g., osteoporosis. In the REal worlD Effectiveness and Safety (REDES) study of mepolizumab in a multicentric Spanish cohort of asthma patients, mepolizumab effectively reduced clinically severe asthma exacerbations and decreased OCS dependence. This post-hoc analysis further evaluates mepolizumab's de-escalation effect on OCS dose. Patients enrolled in REDES who had OCS consumption data available for 12 months pre- and post-mepolizumab treatment were included in this analysis. Primary outcomes were to determine the change in the proportion of patients eligible for anti-osteoporotic treatment due to the changes in OCS consumption before and after 1 year of mepolizumab treatment. All analyses are descriptive. Approximately one-third (98/318; 30.8%) of patients in REDES were on maintenance OCS at the time of mepolizumab treatment initiation. In REDES, mean cumulative OCS exposure decreased by 54.3% after 1 year of treatment. The proportion of patients on high-dose OCS (≥7.5 mg/day) fell from 57.1% at baseline to 28.9% after 12 months of mepolizumab treatment. Thus, 53.6% of OCS-dependent asthma patients treated with mepolizumab would cease to be candidates for anti-osteoporotic treatment according to guidelines thresholds

Biologic Therapy in Refractory Non-Multiple Sclerosis Optic Neuritis Isolated or Associated to Immune Mediated Inflammatory Diseases. A Multicenter Study

We aimed to assess the e cacy of biologic therapy in refractory non-Multiple Sclerosis (MS) Optic Neuritis (ON), a condition more infrequent, chronic and severe than MS ON. This was an open-label multicenter study of patients with non-MS ON refractory to systemic corticosteroids and at least one conventional immunosuppressive drug. The main outcomes were Best Corrected Visual Acuity (BCVA) and both Macular Thickness (MT) and Retinal Nerve Fiber Layer (RNFL) using Optical Coherence Tomography (OCT). These outcome variables were assessed at baseline, 1 week, and 1, 3, 6 and 12 months after biologic therapy initiation. Remission was defined as the absence of ON symptoms and signs that lasted longer than 24 h, with or without an associated new lesion on magnetic resonance imaging with gadolinium contrast agents for at least 3 months. We studied 19 patients (11 women/8 men; mean age, 34.8 13.9 years). The underlying diseases were Bechet?s disease (n = 5), neuromyelitis optica (n = 3), systemic lupus erythematosus (n = 2), sarcoidosis (n = 1), relapsing polychondritis (n = 1) and anti-neutrophil cytoplasmic antibody -associated vasculitis (n = 1). It was idiopathic in 6 patients. The first biologic agent used in each patient was: adalimumab (n = 6), rituximab (n = 6), infliximab (n = 5) and tocilizumab (n = 2). A second immunosuppressive drug was simultaneously used in 11 patients: methotrexate (n = 11), azathioprine (n = 2), mycophenolate mofetil (n = 1) and hydroxychloroquine (n = 1). Improvement of the main outcomes was observed after 1 year of therapy when compared with baseline data: mean SD BCVA (0.8 0.3 LogMAR vs. 0.6 0.3 LogMAR; p = 0.03), mean SD RNFL (190.5 175.4 m vs. 183.4 139.5 m; p = 0.02), mean SD MT (270.7 23.2 m vs. 369.6 137.4 m; p = 0.03). Besides, the median (IQR) prednisone-dose was also reduced from 40 (10?61.5) mg/day at baseline to. 2.5 (0?5) mg/day after one year of follow-up; p = 0.001. After a mean SD follow-up of 35 months, 15 patients (78.9%) achieved ocular remission, and 2 (10.5%) experienced severe adverse events. Biologic therapy is e ective in patients with refractory non-MS ON

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Soil contamination in nearby natural areas mirrors that in urban greenspaces worldwide

Soil contamination is one of the main threats to ecosystem health and sustainability. Yet little is known about the extent to which soil contaminants differ between urban greenspaces and natural ecosystems. Here we show that urban greenspaces and adjacent natural areas (i.e., natural/semi-natural ecosystems) shared similar levels of multiple soil contaminants (metal(loid)s, pesticides, microplastics, and antibiotic resistance genes) across the globe. We reveal that human influence explained many forms of soil contamination worldwide. Socio-economic factors were integral to explaining the occurrence of soil contaminants worldwide. We further show that increased levels of multiple soil contaminants were linked with changes in microbial traits including genes associated with environmental stress resistance, nutrient cycling, and pathogenesis. Taken together, our work demonstrates that human-driven soil contamination in nearby natural areas mirrors that in urban greenspaces globally, and highlights that soil contaminants have the potential to cause dire consequences for ecosystem sustainability and human wellbeing

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file