The ECAPS Experiment for Solar Cell Characterization in the Stratosphere

The ECAPS project (Experimental Characterization of Advanced Photovoltaics in the Stratosphere) aims at the characterization of performance of a number of different solar cells in the stratospheric environment. ECAPS has been selected to fly as a zero-pressure balloon payload in the frame of the HEMERA H2020 project. Flight is scheduled for August 2022 from CNES’ base in Timmins, Canada. Testing solar cells in the stratosphere is of great interest for the development of High-Altitude Pseudo Satellite (HAPS) platforms, which will be equipped with high efficiency, flexible solar cells capable to operate at 20-30 km altitude for weeks or months, as well as to perform high-quality calibration of spacecraft solar cells in a near-air mass zero environment. The experiment includes a panel with up to 4 solar cells of different kinds (multi-junction GaAs, CIGS, perovskite, etc.), a dedicated I/V curve recording circuit, temperature and irradiance sensors, and an inertial measurement unit to monitor the instantaneous attitude of the gondola. During the ascent part of the flight, the I/V characteristic curves of the cells will be continuously recorded so to allow for comparison of performance of the different photovoltaic technologies in identical, real stratospheric flight conditions, as well as to detect performance changes with external temperature, irradiance and altitude. Upon recovery of the experiment, post-flight inspection will also yield useful information on the solar cell compatibility with the high altitude environment

MRI-LINAC: A transformative technology in radiation oncology

Advances in radiotherapy technologies have enabled more precise target guidance, improved treatment verification, and greater control and versatility in radiation delivery. Amongst the recent novel technologies, Magnetic Resonance Imaging (MRI) guided radiotherapy (MRgRT) may hold the greatest potential to improve the therapeutic gains of image-guided delivery of radiation dose. The ability of the MRI linear accelerator (LINAC) to image tumors and organs with on-table MRI, to manage organ motion and dose delivery in real-time, and to adapt the radiotherapy plan on the day of treatment while the patient is on the table are major advances relative to current conventional radiation treatments. These advanced techniques demand efficient coordination and communication between members of the treatment team. MRgRT could fundamentally transform the radiotherapy delivery process within radiation oncology centers through the reorganization of the patient and treatment team workflow process. However, the MRgRT technology currently is limited by accessibility due to the cost of capital investment and the time and personnel allocation needed for each fractional treatment and the unclear clinical benefit compared to conventional radiotherapy platforms. As the technology evolves and becomes more widely available, we present the case that MRgRT has the potential to become a widely utilized treatment platform and transform the radiation oncology treatment process just as earlier disruptive radiation therapy technologies have done

Updates on radiotherapy-immunotherapy combinations: Proceedings of 6th annual ImmunoRad conference.

Focal radiation therapy (RT) has attracted considerable attention as a combinatorial partner for immunotherapy (IT), largely reflecting a well-defined, predictable safety profile and at least some potential for immunostimulation. However, only a few RT-IT combinations have been tested successfully in patients with cancer, highlighting the urgent need for an improved understanding of the interaction between RT and IT in both preclinical and clinical scenarios. Every year since 2016, ImmunoRad gathers experts working at the interface between RT and IT to provide a forum for education and discussion, with the ultimate goal of fostering progress in the field at both preclinical and clinical levels. Here, we summarize the key concepts and findings presented at the Sixth Annual ImmunoRad conference

Updates on radiotherapy-immunotherapy combinations: Proceedings of 6(th) annual ImmunoRad conference

Focal radiation therapy (RT) has attracted considerable attention as a combinatorial partner for immunotherapy (IT), largely reflecting a well-defined, predictable safety profile and at least some potential for immunostimulation. However, only a few RT-IT combinations have been tested successfully in patients with cancer, highlighting the urgent need for an improved understanding of the interaction between RT and IT in both preclinical and clinical scenarios. Every year since 2016, ImmunoRad gathers experts working at the interface between RT and IT to provide a forum for education and discussion, with the ultimate goal of fostering progress in the field at both preclinical and clinical levels. Here, we summarize the key concepts and findings presented at the Sixth Annual ImmunoRad conference

Development of low cost solar panel with cover glass for small satellites applications

Solar panels for power generation in space are quite expensive and even small improvements in the development, production and qualification process may result in significant savings for low cost small satellites. This paper presents the research activities carried out in collaboration between the University of Pisa and Alta SpA about the design, manufacturing and assembly of a photovoltaic panel for small satellite applications in preparation of a test flight scheduled for early 2013 on the UNISAT5 small spacecraft. The method developed is based on low cost and “low tech” (but reliable) techniques to assemble and qualify the panel. The approach adopted uses a printed circuit board where bare cells are installed by means of a double-sided insulating adhesive tape and each cell is covered with cerium doped borosilicate glass, using a controlled volatility silicone. Bonding was performed with a dedicated vacuum bag technique, developed in-house. We outline the panel design, the manufacturing processes and the results of electrical and thermal vacuum tests carried out on the protoflight model

Role of radiosurgery/stereotactic radiotherapy in oligometastatic disease: Brain oligometastases

During the natural history of oncologic diseases, approximately 20-40% of patients affected by cancer will develop brain metastases. Non-small lung cancer, breast cancer, and melanoma are the primaries that are most likely to metastasize into the brain. To date, the role of Radiosurgery/Stereotactic Radiotherapy (SRS/SRT) without Whole brain irradiation (WBRT) is a well-recognized treatment option for patients with limited intracranial disease (1-4 BMs) and a life-expectancy of more than 3-6 months. In the current review, we focused on randomized studies that evaluate the potential benefit of radiosurgery/stereotactic radiotherapy for brain oligometastases. To date, no difference in overall survival has been observed between SRS/SRT alone compared to WBRT plus SRS. Notably, SRS alone achieved higher local control rates compared to WBRT. A possible strength of SRS adoption is the potential decreased neurocognitive impairment

Validation of a Low-Thrust Spacecraft Simulator for Earth Observation Missions

This paper presents the new developments and the validation of the software suite SATSLab (Spacecraft Attitude, Trajectory and Subsystems Laboratory); a low-thrust space mission simulator developed as a collaboration between Alta SpA and the University of Pisa [1]. SATSLab is a fundamental tool for mission analysis and spacecraft subsystem sizing for missions where the usage of electric propulsion systems is envisaged. SATSLab allows for an accurate assessment of orbital trajectory and spacecraft subsystems energy status, fundamental aspects to take into account in the design of missions with small satellites and limited onboard resources. SATSLab has been recently fitted with new functionalities specially aimed at easing the design of advanced Earth observation missions. A new module for ground station visibility and for the computation of link budgets has been integrated. The NRLMSISE-00 atmospheric model has been added for an accurate atmospheric drag computation. SATSLab has been validated by several numeric applications and semi-analytic comparisons. In the paper, a representative Earth-observation mission scenario is presented; highlighting the simulator capability to reveal the non-trivial features of the energy-trajectory interplay

Electric Propulsion Microsatellites in a Versatile Constellation for Remote Sensing Applications

The paper presents the study of a microsatellites constellation equipped with electric thrusters to support land use monitoring and management while reducing mission cost and retaining high performance. The activity was carried out in collaboration between Alta SpA and University of Pisa. The usage of electric thrusters to compensate atmospheric drag and perform orbital maneuver enables microsatellites to maintain low-altitudes (below 500 km) and achieve autonomously operational orbits. This approach allows at selecting a wide range of orbits and designing a constellation based on standard platforms equipped with various optical instruments (multispectral, hyperspectral and thermal infrared). Alta’s HT100, a 100W Hall thruster, was assumed as reference propulsion system for this study. The 60 kg class platform designed may host a wide range of possible Earth observation payloads in terms of available volume (up to 20 liters), mass (up to 12 kg), power (30 W at least), data transfer speed (up to 100 Mbit/s), and pointing accuracy (down to 0.025 deg). As a result of the study, we show that the combination of microplatforms and electric propulsion outclasses classical larger spacecraft platforms based on chemical propulsion systems, with better operational flexibility, revisit frequencies and geographical coverage performance

A Regional Microsatellite Constellation with Electric Propulsion in Support of Tuscan Agriculture

This paper presents the mission design of a microsatellite constellation with electric propulsion to monitor and support the agriculture activities in the Tuscany region. The activity was carried out in collaboration between Alta SpA and University of Pisa. Starting from the user requirements and considering the performance of existing small optical instruments, our analysis has resulted in a constellation based on four microsatellites, each equipped with a different optical instrument (multispectral, hyperspectral and thermal infrared) responding to specific spatial and spectral perfomance. In order to guarantee very frequent revisit, microsatellites are placed in Sun-synchronus Repeating Ground Track (SSRGT) orbits from 358 km to 554 km. Each microsatellite is equipped with a low power Hall effect thruster, to provide orbital maneuvering capability and drag compensation for station keeping. The software suite SATSLab (Spacecraft Attitude, Trajectory and Subsystems LABoratory), suited for Earth Observation missions analysis, has been used to evaluate platform capabilities to compensate atmospheric drag, to perform orbital transfers, and to evaluate the instantaneous balance of energy exchanges onboard due to thruster firing, operation of observation instruments and data transmission