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Abstract Storage technologies play a crucial role in polygeneration plants that attempt to integrate power, thermal and cooling energy systems in order to maximize process efficiency and reduce operating cost. With the increasing penetration of renewable energy into the plant, storage technologies help to dampen the intermittency problem in their energy supply whilst at the same time perform peak shaving to reduce primary energy consumption, thus mitigating pollutant emission. Among the various storage technologies, Liquid Air Energy Storage (LAES) have gathered research interest due to its capability of simultaneously producing electrical and cooling power. Furthermore, unlike Electrochemical Energy Storage (EES) technologies, the LAES lifetime is not heavily dependent on its duty cycle, thus allowing for a calendar life twice or thrice that of EES. In this paper, the economic dispatch of an Eco-building in Singapore has been evaluated using a mixed-integer quadratic programming solver by comparing the adoption of EES and LAES within a capacity range of 300kWh-2000kWh. At the higher end of the capacity range, the LAES configuration results in a higher Net Present Value after 20 years and a shorter time period to obtain the Return of Investment compared to that of EES. At the lower capacity range, both technologies give similar financial returns. Analysis of the results show LAES to be a promising technology to compete with EES in the context of a polygeneration plant and further technology integration is discussed. [ABSTRACT FROM AUTHOR]

A magnetic spectrometer has been developed for the AWAKE experiment at CERN in order to measure the energy distribution of bunches of electrons accelerated in wakefields generated by proton bunches in plasma. AWAKE is a proof-of-principle experiment for proton-driven plasma wakefield acceleration, using proton bunches from the SPS. Electron bunches are accelerated to O (1 GeV) in a rubidium plasma cell and then separated from the proton bunches via a dipole magnet. The dipole magnet also induces an energy-dependent spatial horizontal spread on the electron bunch which then impacts on a scintillator screen. The scintillation photons emitted are transported via three highly-reflective mirrors to an intensified CCD camera, housed in a dark room, which passes the images to the CERN controls system for storage and further analysis. Given the known magnetic field and determination of the efficiencies of the system, the spatial spread of the scintillation photons can be converted to an electron energy distribution. A lamp attached on a rail in front of the scintillator is used to calibrate the optical system, with calibration of the scintillator screen's response to electrons carried out at the CLEAR facility at CERN. In this article, the design of the AWAKE spectrometer is presented, along with the calibrations carried out and expected performance such that the energy distribution of accelerated electrons can be measured. [ABSTRACT FROM AUTHOR]

Radiation therapy (RT) for chordomas and chondrosarcomas typically requires doses >70 Gy for optimal local tumor control. Proton therapy may afford safer dose escalation to the tumor, however, prospective data on outcomes and toxicity are lacking. We report results from a prospective clinical trial of proton beam radiation for the treatment of chordomas and chondrosarcomas. Fifty-five patients with pathologically confirmed, non-metastatic chordoma or chondrosarcoma with an ECOG score <=2 were enrolled in a single-institution prospective trial of proton therapy from 2010-2018. Forty-seven patients received adjuvant RT, 5 received definitive RT, 1 received neoadjuvant RT, and 1 received RT for recurrence; 1 patient enrolled did not receive RT and was excluded from toxicity and survival analyses. Median dose was 78.3 Gy (cobalt Gray equivalent [CGE]) (range 50.4 – 79.2 Gy [CGE]) using protons only (n=21), combination protons/IMRT (n=33) with double-scatter or pencil beam scanning techniques, or IMRT only (n=2). Patients were followed with MRI or CT at three-month intervals. The primary endpoints were feasibility and <=20% rate of unexpected acute grade ≥3 toxicity. Secondary endpoints included cancer-specific outcomes and toxicity. Toxicities were scored using CTCAEv4.0. Kaplan Meier analysis was used to estimate local control, progression-free survival, and overall survival with respect to the date of RT completion. Local control was defined by most recent imaging; progression-free and overall survival were defined by most recent follow-up. Of the 54 patients who were analyzed (22 males, 32 female) with a median age of 54, 26 had skull base chordomas, 10 had sacral chordomas, 6 had spinal chordomas, 9 had base of skull chondrosarcomas, 1 had sacral chondrosarcoma, and 2 had sinonasal chondrosarcomas. Positive margins or gross disease was noted in 67% of patients at the time of RT. Median follow-up was 72 months, with an Overall survival of 45/54 (83%) patients alive at last follow-up. Local failure-free survival and progression-free survival were 70% and 68% respectively at a median follow up of 69 months. Feasibility endpoints were met, with only 3/55 (5.5%) patient RT plans failing to meet dosimetric constraints with protons and 4/54 (7.4%) experiencing a delay or treatment break >5 days. Five patients developed distant disease, 3 with a metastasis in the craniospinal axis, and 1 with a biopsy-confirmed inguinal lymph node metastasis, and 1 with distal iliac and femur metastases. Among the 9/54 patients who died, 4 deaths were not attributed to treatment or recurrence. There were no grade 4 toxicities. One grade 3 acute toxicity (sensory neuropathy) was recorded. The only 2 grade 3 late toxicities recorded, osteoradionecrosis and intranasal carotid blowout, occurred in a single patient. We report favorable feasibility, local tumor control, survival, and toxicity following high-dose proton therapy for chordomas and chondrosarcomas. [ABSTRACT FROM AUTHOR]

• Study of the shadowing of coherent of polarization radiation. • Shadowing effects disappear for distances much shorter than those predicted. • The diffraction counteracts the destructive interference related to the shadowing. • Any electrically-polarizable medium or surface can be a source of radiation. • These studies are well-adapted to novel and compact accelerator technologies. We report on the study of shadowing of electromagnetic fields radiated in the Terahertz (THz) region from two consecutive sources of coherent diffraction and transition radiation. In these conditions, the formation length is predicted to be ≲ 100 m , and shadowing effects should result in an almost complete suppression of radiated fields within distances of the order of tens of centimeters. We experimentally measured that shadowing effects disappear for distances significantly shorter than those predicted. We propose a new model that explains our experimental observations by taking into account 3D diffraction effects. These findings will have a positive impact on the beneficial use of consecutive radiators both for the generation of intense electromagnetic radiation and for beam diagnostics using coherent polarization radiation from ultra-relativistic charged particles. [ABSTRACT FROM AUTHOR]