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The Miniaturized Detector for Application in Space (MIDAS) device is developed in response to the requirement of the European Space Agency for a device whose size, power consumption, and radiation data output would increase the level of space‐flight crew autonomy regarding operational decisions related to radiation hazards. It is designed as a wristwatch‐dimension cube detector for measuring track direction and energy deposition in silicon pixels, as well as energy depositions by neutrons in a plastic scintillator, which is the core of the cube. Miniaturization was achieved by using fully depleted silicon pixel detectors with the signal processing electronics residing on pixel. The device concept, simulated performance, and first measurements are presented. Simulation results indicate that it is possible to discriminate all significant ions with the aid of appropriate variables constructed using the data provided by the device. 252Cf energy spectra were reconstructed successfully using measurements obtained with the first device prototype. Key Points: The first design of depleted monolithic active pixel sensors for charged particle measurement in space is presentedA sensitive cube with wristwatch dimensions for dosimetry of charged particles and neutrons in mixed radiation fields has been designed [ABSTRACT FROM AUTHOR]

Aim: Beta-thalassaemia major (TM) affects oxygen flow and utilization and reduces patients’ exercise capacity. The aim of this study was to assess phase I and phase II oxygen kinetics during submaximal exercise test in thalassaemics and make possible considerations about the pathophysiology of the energy-producing mechanisms and their expected exercise limitation. Methods: Twelve TM patients with no clinical evidence of cardiac or respiratory disease and 10 healthy subjects performed incremental, symptom-limited cardiopulmonary exercise testing (CPET) and submaximal, constant workload CPET. Oxygen uptake ( Vo2), carbon dioxide output and ventilation were measured breath-by-breath. Results: Peak Vo2 was reduced in TM patients (22.3 ± 7.4 vs. 28.8 ± 4.8 mL kg−1 min−1, P < 0.05) as was anaerobic threshold (13.1 ± 2.7 vs. 17.4 ± 2.6 mL kg−1 min−1, P = 0.002). There was no difference in oxygen cost of work at peak exercise (11.7 ± 1.9 vs. 12.6 ± 1.9 mL min−1 W−1 for patients and controls respectively, P = ns). Phase I duration was similar in TM patients and controls (24.6 ± 7.3 vs. 23.3 ± 6.6 s respectively, P = ns) whereas phase II time constant in patients was significantly prolonged (42.8 ± 12.0 vs. 32.0 ± 9.8 s, P < 0.05). Conclusion: TM patients present prolonged phase II on-transient oxygen kinetics during submaximal, constant workload exercise, compared with healthy controls, possibly suggesting a slower rate of high energy phosphate production and utilization and reduced oxidative capacity of myocytes; the latter could also account for their significantly limited exercise tolerance. [ABSTRACT FROM AUTHOR]

The purpose of our study was assessment of the relative contribution of the systems involved in blood gas exchange to the limited exercise capacity in patients with β-thalassemia major (TM) using integrative cardiopulmonary exercise testing (CPET) with estimation of oxygen kinetics. The study consisted of 15 consecutive TM patients and 15 matched controls who performed spirometric evaluation, measurement of maximum inspiratory pressure (Pimax) and an incremental symptom-limited CPET on a cycle ergometer. Exercise capacity was markedly reduced in TM patients as assessed by peak oxygen uptake (pVO2, mL/kg/min: 22.1±6.6 vs 33.8±8.3; P<0.001) and anaerobic threshold (mL/kg/min: 13.0±3.0 vs 18.7±4.6; P<0.001) compared with controls. No ventilatory limitation to exercise was noted in TM patients (VE/VCO2 slope: 23.4±3.2 vs 27.8±2.6; P<0.001 and breathing reserve, %: 42.9±17.0 vs 29.5±12.0; P<0.005) and no difference in oxygen cost of work (peak VO2/WR, mL/min W: 12.2±1.7 vs 12.2±1.5; P=NS). Delayed recovery oxygen kinetics after exercise was observed in TM patients (VO2/ t slope, mL/kg/min2: 0.67±0.27 vs 0.93±0.23; P<0.05) that was significantly correlated with Pimax at rest ( r: 0.81; P<0.001). The latter was also significantly correlated to pVO2 ( r: 0.84; P<0.001) and inversely correlated to ferritin levels ( r: −0.6; P<0.02). Exercise capacity is markedly reduced in TM patients and this reduction is highly associated with the limited functional status of peripheral muscles. [ABSTRACT FROM AUTHOR]

An abstract of the article "Interval training effects on oxygen kinetics in heart failure patients," by P. Roditis and colleagues is presented.

An abstract of the study "End-Tidal Carbon Dioxide Pressure During Maximum Cardiopulmonary Exercise Testing Predicts Mortality in Patients With Congestive Heart Failure," by S. Drakos and colleagues is presented.

Purpose: Time is the key criterion in the management of non-arteritic central retinal artery occlusion (NA-CRAO). However, the precise onset of vision loss is often difficult to determine. This study aimed to evaluate the temporal changes of retinal thickness in acute NA-CRAO and the potential of this parameter to be used as a surrogate marker to estimate the onset of retinal ischaemia., Methods: Optical coherence tomography was used to continuously assess retinal thickness and oedema progression rate in six porcine eyes. Additionally, a retrospective analysis of 12 patients with acute NA-CRAO was performed to determine association strength and progression rate between retinal thickness and onset of ischaemia. All Optical coherence tomography (OCT) scans (pigs and NA-CRAO patients) were performed within an ischaemic time frame of up to 9 hr., Results: Retinal oedema progression rate in pigs was 25.32 µm/hr [CI 95%: 24.24-26.40 µm/hr]. Retrospective analysis of the patients revealed a strong correlation between retinal oedema and duration of ischaemia (Spearman's rho = 0.77, p = 0.004) with an estimated progression rate of 10.02 µm/hr [CI 95%: 3.30-16.74 µm/hr]., Conclusion: Retinal thickness increases with oedema formation, and ischaemia onset is strongly correlated with this structural biomarker in both, pigs and NA-CRAO patients. Prospective clinical trials will have to determine the clinical feasibility of retinal thickness measurements as a biomarker to support clinical management of NA-CRAO., (© 2020 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Objective: The thrombomodulin/protein C and VWF/ADAMTS-13 pathways are disturbed in sepsis and have been implicated in the coagulation disorders that characterize the septic syndrome. We aimed to assess the variation of these endothelial parameters during sepsis and their putative association with outcome, in critically ill, septic patients., Methods: We monitored 34 septic patients, 23 of whom improved (group A) while 11 deteriorated (group B). We assessed ADAMTS-13 levels, VWF activity, soluble thrombomodulin, and protein C activity upon admission to the ICU (time point 0) and at the time of a change in the clinical condition (remission or deterioration, time point 1)., Results: In group A, thrombomodulin and VWF increased at time point 1 compared to time point 0 (P = 0.011, P = 0.028, respectively). In group B, protein C and ADAMTS-13 significantly decreased (P = 0.023, P = 0.026, respectively), while VWF, VWF/ADAMTS-13 ratio, and the thrombomodulin/protein C ratio increased (P = 0.02, P = 0.002, P = 0.01, respectively). Protein C (> or ≤17%) and ADAMTS-13 percentage difference (> or ≤22%) were independently associated with sepsis outcome among the endothelial variables tested., Conclusions: An ongoing endothelial/hemostatic disorder was established during sepsis, observed even at clinical improvement. Among the variables tested, protein C and ADAMTS-13 change were associated with outcome., (© 2018 John Wiley & Sons Ltd.)

Objective: The importance of abnormalities observed in the microcirculation of patients with arterial hypertension (AH) is being increasingly recognized. The authors aimed to evaluate skeletal muscle microcirculation in untreated, newly diagnosed hypertensive patients with NIRS, a noninvasive method that evaluates microcirculation., Methods: We evaluated 34 subjects, 17 patients with AH (13 males, 49±13 years, BMI: 26±2 kg/m 2 ) and 17 healthy controls (12 males, 49±15 years, BMI: 25±3 kg/m 2 ). The thenar muscle StO 2 (%) was measured by NIRS before, during and after 3-minutes vascular occlusion to calculate OCR (%/min), EF (%/min), and RHT (minute). The dipping status of hypertensive patients was assessed., Results: The RHT differed between AH patients and healthy subjects (2.6±0.3 vs 2.1±0.3 minutes, P<.001). Dippers had higher EF than nondippers (939±280 vs 710±164%/min, P=.05)., Conclusions: The study suggests an impaired muscle microcirculation in newly diagnosed, untreated AH patients., (© 2017 John Wiley & Sons Ltd.)