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The design of a compact 2 × 2 diamond matrix with independent and redundant pixels optimized for the spectrometric neutron camera of the SPARC tokamak is presented in this article. Such a matrix overcomes the constraints in dynamic range posed by the size of a single diamond sensor while keeping the ability to perform energy spectral analysis, marking a significant advancement in tokamak neutron diagnostics. A charge pre-amplifier based on radio frequency amplifiers based on InGaP technology transistors, offering up to 2 GHz bandwidth with high robustness against radiation, has been developed. A first single-channel device has been tested and proven to provide a fast signal development time of 20–25 ns, necessary to mitigate pileup effects while offering precise energy measurements. As the diamond sensors may suffer from polarization effects due to the trapping of charges at the diamond/metal interface, a periodical bias inversion can guarantee optimal performance. To facilitate that, a reversible high voltage power supply has been developed. The ongoing development of data acquisition equipment and real-time processing algorithms based on programmable gate arrays further enhances the neutron camera's capabilities. [ABSTRACT FROM AUTHOR]

The ITER Radial Gamma-Ray Spectrometer (RGRS) consists of three gamma-ray detectors observing the plasma through three collimated, coplanar, radial lines of sight (LoS). The system was initially designed to monitor the runaway electron emission and the alpha-particle density profile [Nocente et al., Nucl. Fusion 57, 076016 (2017)]. This work presents a novel technique for measuring the fusion power during D-T operation using the RGRS. This method is based on the absolute measurement of the 17 MeV fusion gamma-rays and a semi-analytical computation of their transport from the plasma source to the detectors. This approach was initially developed and tested at JET during the second D-T campaign (DTE2) on a single LoS diagnostic [Dal Molin et al., Phys. Rev. Lett. (submitted) (2024); Rebai et al., Phys. Rev. C (submitted) (2024); and Marcer et al., Nucl. Fusion (unpublished) (2024)]. This work exploits the multiple LoS of the RGRS to create a combined virtual diagnostic whose detected fraction of the total plasma emission is less affected by variations in the plasma emission profile, reducing systematic uncertainties on the estimated total emission, compared to the individual detectors. [ABSTRACT FROM AUTHOR]

A new 14 MeV neutron spectrometer utilizing the magnetic proton recoil (MPR) technique is under development for the SPARC tokamak. This instrument measures neutrons by converting them into protons, whose momenta are subsequently analyzed using a series of magnets before detection by an array of scintillators known as the hodoscope. In this work, we explore various solutions for the hodoscope detectors through laboratory tests with radioactive sources and simulations. We present findings on light collection and pulse shape discrimination based on detector types, as well as optimal solutions for photo-detectors studying the differences between SiPM and PMT. Our results also led to the determination of a better optimized design for the hodoscope detectors, consisting of a 0.7 cm width and a 13 cm length EJ276D scintillation rod. [ABSTRACT FROM AUTHOR]

Background: The spread of coronavirus disease 2019 (COVID-19) is overwhelming the response of many regional health services across Italy. This article aims to report and discuss the data of the first 8 weeks of COVID-19 epidemic in the emergency department (ED) of the University Hospital of Parma., Methods: The ED visits were analyzed as follows: total ED visits, divided in COVID-19/ non-COVID-19 cases, and in trauma-related/non-trauma-related cases; outcome (i.e., discharged, admitted, dead in the ED) of patients, altogether or stratified according to triage class; age classes of the entire ED population., Results: Total ED visits decreased starting from the first days of the outbreak, then exhibiting progressive growth afterwards. COVID suspected cases rapidly increased, whereas non-COVID suspected dropped and remained well below the standard. Trauma-related cases declined, both as ED visits and as hospital admissions. The percentage and absolute number of patients admitted to hospital wards progressively increased, rapidly overwhelming the number of cases that could be discharged. The admission rate in the lowest priority classes also displayed a marked increase. The youngest age classes dramatically declined, whilst the oldest progressively increased, remaining considerably over the standard rate of the local ED., Conclusions: The COVID-19 pandemic has obliged the health care systems to undergo a paradigm shift. Even triage criteria have partially lost their meaning, as shown by the dramatic increase of hospital admissions, even in the lowest priority classes. A deep re-organizational process of the ED was undertaken. Hospitals must be constantly resilient and prepared to these new emergencies in terms of equipment, medical and nurses staff, larger bed capacity in short time, availability of intensive and sub-intensive beds, and flexibility.

Objective: Non-invasive assessment using a pharmacological provocative test is an essential part of the workup of patients admitted to the emergency department with chest pain. Some doubts, however, remain about the safety of dipyridamole stress echocardiography in patients with non-diagnostic troponin and ECG., Methods and Results: Twenty-nine consecutive patients admitted to the emergency department with chest pain and no evidence of acute coronary syndrome were subjected to standard dipyridamole stress echocardiography. Blood samples for measurement of galectin-3, NT-proBNP and high-sensitivity troponin T (HS-TnT) were collected at the baseline and after provocative testing. The provocative test was positive in 7/29 patients. As compared with baseline measurements, no significant differences were observed in 1-h values of HS-TnT (10.7 versus 10.5 ng/L; P = 0.085) and galectin-3 (14.3 versus 13.7 ng/mL; P = 0.128), whereas values of NT-proBNP were slightly higher (126 versus 111 ng/L; P = 0.002). The 1-h delta variation of patients with a positive provocative test was significantly higher than that of patients with negative provocative testing for galectin-3 (1.12 versus 1.00; P < 0.001), but not for HS-TnT (0.98 versus 1.00; P = 0.184) and NT-proBNP (1.10 versus 1.04; P = 0.344). The 1-h delta variation of galectin-3 was > 1 in all patients with a positive provocative test as compared with 50% of patients with a negative provocative test (P = 0.018)., Conclusions: Dipyridamole stress testing did not trigger clinically meaningful injuries to the myocardium. Galectin-3 testing may hence be preliminarily regarded as a complementary means for enhancing the diagnostic value of provocative testing. It is also worthwhile investigating whether patients with abnormal response to a provocative test and increased galectin-3 values may be targeted with specific therapy.

Background: The assessment of cardiospecific troponins is the main stay for diagnosing myocardial injury, although their diagnostic sensitivity remains suboptimal at patient admission to the emergency department (ED), thus paving the way for translational research to identify early and complementary biomarkers which may help improve the diagnostic sensitivity of high-sensitivity troponin immunoassays at patient presentation to the ED., Aim: To investigate whether heart-type fatty acid binding protein (H-FABP) provides distinctive and/or adjunctive information over high-sensitivity troponin I (HS-TnI) in ED patients undergoing dipyridamole stress testing., Methods: Thirty consecutive ED patients with chest pain but no myocardial ischaemia were challenged with dipyridamole-atropine and followed by echocardiography. Blood samples for assessing H-FABP and HS-TnI were collected before the dipyridamole challenge, immediately after, and 6 h afterwards., Results: The concentration of HS-TnI in the whole cohort of patients did not vary significantly throughout the study period, whereas H-FABP significantly increased after the test (4.2 ng/mL, p = 0.003), but not 6 h afterwards (3.8 ng/mL, p = 0.372) compared to baseline (4.0 ng/mL). The kinetics was similar in patients with positive or negative results of stress testing. The frequency of biomarker increase after the test was greater for H-FABP than for HS-TnI immediately after the pharmacological challenge (77% vs. 53%), but was lower 6 h afterwards (30% vs. 63%). The number of patients with values exceeding the diagnostic threshold of both biomarkers remained constant throughout the study period., Conclusions: These results suggest that dipyridamole stress echocardiography does not trigger substantial myocardial injury. We have also shown that release of H-FABP from stressed myocardium occurs without progression towards irreversible necrosis, and is more precious than that of TnI.