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Hematite α-Fe2O3 pseudocubes, rhombohedra, and spindlelike particles were prepared via a low cost and environmentally friendly microwave route. The structure and morphology were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Possible formation mechanisms of the particles are discussed. The design of the sensor includes a conductor-backed coplanar waveguide (CBCPW) on which a hematite sensitive layer is deposited. Hematite deposition was realized by doctor-blade on areas identified as the most responsive by near-field microwave microscopy (NFMM). A comparative microwave gas sensing study was conducted to evaluate the gas response of these morphologies upon ammonia exposure at room temperature. This paper represents a first look at the shape effect involved in microwave transduction, as each morphology presented a significant different behavior upon ammonia adsorption.

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In this paper, authors propose a study on microwave gas sensors and the influence of critical key parameters such as the sensitive material and the circuit conception process. This work aims to determine the influence of these parameters on the quality of the final response of the microwave gas sensor. The fixed geometry of the sensor is a microstrip interdigital capacitor coated with a sensitive layer excited with two 50 Ω SMA ports. The sensitive material has been chosen in order to interact with the target gas: ammonia. Indeed, this gas interacts with phthalocyanine and metal oxides like hematite, TiO 2 . To explore the effect of the circuit manufacturing process, three series of samples are prepared. The first series of sensors is produced by classical UV photolithography (process) in the laboratory. The second series of sensors is produced by a subcontractor specialized in rf circuits. The third series is obtained by the experimental platform of the FEMTO-ST laboratory with EVG620 Automated Mask Alignment System Nanoimprint lithography in a clean room. To examine the reliability of this gas sensor at room temperature, it was exposed to different ammonia gas concentrations from 100 to 500 ppm in an argon flow to eliminate coadsorption phenomena. According to the recorded frequency responses, the reflection and transmission coefficients show a change of resonance amplitude due to electrical characteristic modification. This can be correlated to the presence of gaseous ammonia. The chemical nature of the sensitive material layer has a major influence at the excited frequency range. The process of conception influences the sensor sensitivity. The analysis of the results shows a strong correlation between the injected ammonia concentration and its frequency response. The influence of the critical key parameters cited is discussed here.

Background: Immune-checkpoint inhibitors (ICI) are approved for multiple cancers but can result in ICI-associated myocarditis, an infrequent but life-threatening condition. Elevations in cardiac biomarkers, troponin-I (cTnI), troponin-T (cTnT) and creatine-kinase (CK) are used for diagnosis. However, the temporal elevation of these biomarker elevations with course of disease and their association with outcomes have not been established. Methods: We analyzed the diagnostic accuracy and prognostic performances of cTnI, cTnT and CK in ICI-myocarditis (n=61) in two cardio-oncology units (APHP.Sorbonne, France & Heidelberg, Germany). Major adverse cardio-myotoxic events (MACE) were defined as heart failure, ventricular arrhythmia, atrioventricular/sinus block requiring pacemaker, respiratory muscle failure requiring mechanical ventilation, and related death. Diagnostic performances of troponins were also assessed in an international ICI-myocarditis registry (n=244 independent cases, 13 countries). Results: On presentation, cTnT, cTnI or CK were increased compared to upper reference limit (URL) in 51/52 (98%), 28/34 (82%, p=0.009 vs. cTnT), 33/48 (69%, p<0.0001 vs. cTnT), respectively. This higher rate of positivity for cTnT vs. cTnI was independently confirmed in an international registry. In patients surviving to 30 days, cTnI and CK had normalized in 20/34(59%) and 30/35(86%), respectively, while cTnT had reached normal values in only 5/42(12%), (p<0.0001). The highest value of cTnT/URL within the first 72h of admission performed best in predicting MACE (AUC:0.82) vs. CK/URL (AUC:0.74) and cTnI/URL (AUC:0.67), even after adjustment for age and sex. Maximal value of cTnT/URL≥32 within ≤72h of diagnosis was the best predictor cut-off for MACE (Hazard-ratio=9.4(95% CI 3.1, 28.3), p<0.0001) over a median follow-up of 4 months. cTnT was increased in all patients just before MACE (22/22, 100%) while cTnI and CK values were normal in 3/21(14%) and 6/24(25%) of patients (p<0.0001). Conclusions. Significant discrepancies between cTnT (compared to cTnI, and CK) circulating levels exist in ICI-myocarditis. cTnT is the best predictor of MACE and most suitable for diagnosis and surveillance. A ratio of cTnT/URL<32 within ≤72h of diagnosis identifies a subgroup at low-risk of MACE.

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