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LARES-2 is a new geodetic satellite designed for high-accuracy satellite laser ranging. The orbit altitude of LARES-2 is similar to that of LAGEOS-1, whereas the inclination angle of 70° complements the LAGEOS-1 inclination of 110°; hence, both satellites form the butterfly configuration for the verification of the Lense–Thirring effect. Although the major objective of LARES-2 is testing general relativity, LARES-2 substantially contributes to geodesy in terms of the realization of terrestrial reference frames, recovery of the geocenter motion, pole coordinates, length-of-day, and low-degree gravity field coefficients. We analyze the first 1.5 years of LARES-2 data and test different empirical orbit models for LARES-2 with and without co-estimating low-degree gravity field coefficients to find the best combination strategy with LAGEOS satellites. We found that LARES-2 orbit determination is more accurate than that of LAGEOS-1/2 due to a different satellite construction consisting of a solid sphere with no inner structure. Neither the correction for D0 nor the empirical once-per-revolution along-track accelerations SC/SS have to be estimated for LARES-2 when co-estimating gravity field coefficients. The only empirical parameter needed for LARES-2 is the constant along-track acceleration S0 to compensate for the Yarkovsky–Schach effect. On the contrary, for LAGEOS-1/2, the non-gravitational perturbations affect C30 and Z geocenter estimates when once-per-revolution parameters are not estimated. LARES-2 does not face this issue. LARES-2 improves the formal errors of the Z geocenter component by up to 59% and C20 by up to 40% compared to the combined LAGEOS-1/2 solutions and provides C30 estimates unaffected by thermal orbit modeling issues. [ABSTRACT FROM AUTHOR]

Aim The aim of the study was to describe the epidemiology and clinical characteristic of children hospitalized with pneumonia complicated by lung abscess, as well as to evaluate the long-term sequelae of the disease. Methods A retrospective review of medical records of all patients treated for pulmonary abscess in two tertiary centers was undertaken. Pulmonary function tests and lung ultrasound were performed at a follow-up. Results During the study period, 5151 children with pneumonia were admitted, and 49 (0.95%) cases were complicated with lung abscess. In 38 (77.5%) patients, lung abscess was treated solely with antibiotics, and in nine cases (16.3%) surgically. In 21 (51.21%) children complete radiological regression was documented. The mean time for radiological abnormalities regression was 84.14 ± 51.57 days, regardless of the treatment mode. Fifteen patients were followed up at 61.6 ± 28.3 months after discharge. Lung ultrasound revealed minor residual abnormalities: pleural thickening, subpleural consolidations and line B artefacts in 11 (73.3%) children. Pulmonary function tests results were abnormal in eight (53.3%) patients, the most frequent abnormality being hyperinflation. We did not find a restrictive disorder in any of the children. There were no deaths in our study. Conclusions Lung abscess is a rare but severe complication of pneumonia in children. Most children recover uneventfully with no significant long-term pulmonary sequelae. [ABSTRACT FROM AUTHOR]