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An increased penetration of renewable energy sources is essential for the energy transition. A major role will be played by wind and solar, as they are widely available. Hydropower is another crucial resource, currently covering large shares of power generation (e.g., Norway, Italy, Brazil). Despite little expected growth, in a context of increasing electrification, improved integration of hydropower can play a critical role thanks to programmable operation. This work addresses the modelling of hydropower flexibility in energy system models and analyses the impact of hydropower operation on CO 2 emission-constrained scenarios. To implement the study, a detailed dataset of the Italian programmable hydroelectric plants is created, using open-source information, covering location, rated power, and storage capacity. Inflow timeseries are derived from historical operational data. These new sets of data are employed in OMNI-ES (a multi-node, multi-sector, and multi-vector energy system model) to study optimal configurations and operation of the Italian energy system in decarbonisation scenarios, such as net-zero-CO 2 and Fit-for-55 targets. Considering different operational strategies and multiple historical reference years (impacting the inflow), results demonstrate significant changes in hydropower behaviour and highlight its relevance as zero-carbon resource in terms of both power and energy output, influencing the installation of other technologies. • Energy system modelling with improved detail of hydropower operation. • The role of hydropower reservoir-based plants is assessed as zero-carbon resource. • A detailed database of Italian programmable hydropower plant is built and shared. • Climatic variability impact is studied, simulating diverse timeseries from reference years. • Variations of 5–15 % in installation of non-hydro key technologies are observed. [ABSTRACT FROM AUTHOR]

Sentinel-1A is a 2-ton spacecraft of the Copernicus Earth observation program operated by ESA's Space Operations Centre in Darmstadt, Germany. Sentinel-1A and its sister spacecraft Sentinel-1B operate in a sun-synchronous orbit at about 700 km altitude. On 2016/08/23 17:07:37 UTC, Sentinel-1A suffered from an anomaly resulting in a sudden permanent partial power loss and significant impulsive orbit and attitude changes. A deeper investigation identified that an impulsive orbit change against flight direction of 0.7 mm/s, estimated at the time of the event, gave the best results in terms of GPS residuals. At the same time, a peak attitude off-pointing of 0.7° (around the spacecraft yaw axis) and peak attitude rate increase of 0.04°/s (around the same axis) were observed. The simultaneous occurrence of these anomalies, starting from a sudden attitude change and ending with a permanent partial power loss, made an MMOD (Micro-Meteoroid and Orbital Debris) impact onto a solar array a possible explanation for this event. While the spacecraft is able to continue its mission nominally, a detailed investigation involving ESA's Space Debris and Flight Dynamics experts was conducted. An MMOD impact as an explanation gained further credibility, due to the pictures of the solar array taken by the on-board camera displaying a significant damage area. On September 7th, JSpOC (US Joint Space Operations Centre) informed SDO on 8 tracked fragments that are considered to be released by Sentinel-1A after the impact. This paper addresses the analysis that was performed on the data characterising the attitude and orbit change, the on-board camera image, and the tracked fragments. The data helped to identify the linear momentum vector while a flux analysis helped to identify the origin of the impactor and allowed to understand its mass and size characteristics. [ABSTRACT FROM AUTHOR]

Background Septic thrombophlebitis increases patient morbidity and mortality following metastatic infections, pulmonary emboli, and/or septic shock. Central venous catheter (CVC) removal for occult septic thrombophlebitis challenges current strategy in neutropenic patients. Patients and methods We prospectively evaluated infection-related mortality in 100 acute leukemia patients, with CVC-related bloodstream infection (CRBSI) after chemotherapy, who systematically underwent ultrasonography to identify the need for catheter removal. Their infection-related mortality was compared with that of a historical cohort of 100 acute leukemia patients, with CRBSI after chemotherapy, managed with a clinically driven strategy. Appropriate antimicrobial therapy was administered in all patients analyzed. Results In the prospective series, 30/100 patients required catheter removal for ultrasonography-detected septic thrombophlebitis after 1 median day from BSI onset; 70/100 patients without septic thrombophlebitis retained their CVC. In the historical cohort, 60/100 patients removed the catheter (persistent fever, 40 patients; persistent BSI, 10 patients; or clinically manifest septic thrombophlebitis, 10 patients) after 8 median days from BSI onset; 40/100 patients retained the CVC because they had not clinical findings of complicated infection. At 30 days median follow-up, one patient died for infection in the ultrasonography-assisted group versus 17 patients in the historical cohort (P < 0.01). With the ultrasonography-driven strategy, early septic thrombophlebitis detection and prompt CVC removal decrease infection-related mortality, whereas clinically driven strategy leads to inappropriate number, reasons, and timeliness of CVC removal. Conclusion Ultrasonography is an easy imaging diagnostic tool enabling effective and safe management of patients with acute leukemia and CRBSI. [ABSTRACT FROM AUTHOR]

In total, 124 Streptococcus pyogenes isolates were obtained from throat cultures of different symptomatic patients. All isolates showed M-phenotype macrolide resistance and contained the macrolide efflux gene mef(A). The isolates were screened for the presence and insertion site of mef(A)-containing genetic elements. In 25.8% of the isolates, mef(A) was found to be carried by elements belonging to the Tn 1207.3/Φ10394.4 family inserted in the comEC gene, while 74.2% contained chimeric elements with a different genetic structure and chromosomal location, probably associated with the recently described 60-kb tet(O)– mef(A) element. [ABSTRACT FROM AUTHOR]