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Adsorption of NO, NO2 and NO + NO2 was studied with and without O2 in the gas feed on NaY zeolite (Si/Al = 2.55) at 30 °C and 101.3 kPa. The influence of residual water in NaY was also studied in presence of O2 in the gaseous flux. During adsorption of NO, NO2 is produced in presence of O2 in the gas feed, due to the formation of oxygen species at the surface of the zeolite. Then, created NO2 reacts with residual H2O to form NO. Without O2, the production of NO2 does not occur. If residual H2O is removed, reaction of NO2 with H2O leading to the formation of NO does not happen. Whether with or without O2 in the gas feed during NO2 adsorption, the evolution of NO and NO2 outlet concentrations are similar. First, NO2 is adsorbed, producing NO by reacting with residual H2O and then, the production of NO decreases while NO2 outlet concentration increases. NO2 breakthrough time is slightly higher without O2. In absence of residual water, no NO is produced. Concerning adsorption of NO and NO2 mixture, the evolution of outlet concentrations is different in presence or in absence of O2. With O2, final outlet concentrations of NO and NO2 are not equal to inlet concentrations unlike what happens without O2. With a dried NaY sample, NO2 is adsorbed without forming NO. For all experiments performed, NO is not adsorbed whereas NaY is interesting for NO2 adsorption, even in gaseous mixture adsorption. [ABSTRACT FROM AUTHOR]

Using periodic density functional theory combined with advanced dispersion correction schemes, the adsorption of NO, NO2, CO, H2O and CO2 has been investigated for various cation-exchanged faujasite zeolites. In the context of preventing harmful releases from diesel engines in confined environment, our aim was to find a suitable material able to selectively trap NO, NO2 and CO toward H2O and CO2 which are also present in the exhaust gas and could inhibit adsorption of targeted species. In order to identify the most promising adsorbent materials, we have undertaken a full screening of monovalent cations which can be incorporated into the zeolite and find that Cu+ presents the best adsorption selectivity, followed by Ag+. However, the analysis of the bonds stretching upon adsorption revealed that Cu+, differently from Ag+, activates the N-O bonds in NO and NO2, which might lead to undesirable by-products during the adsorption process. [ABSTRACT FROM AUTHOR]

Background: Understanding of the cerebrospinal fluid (CSF) circulation is essential for physiological studies and clinical diagnosis. Real-time phase contrast sequences (RT-PC) can quantify beat-to-beat CSF flow signals. However, the detailed effects of free-breathing on CSF parameters are not fully understood. This study aims to validate RT-PC's accuracy by comparing it with the conventional phase-contrast sequence (CINE-PC) and quantify the effect of free-breathing on CSF parameters at the intracranial and extracranial levels using a time-domain multiparametric analysis method., Methods: Thirty-six healthy participants underwent MRI in a 3T scanner for CSF oscillations quantification at the cervical spine (C2-C3) and Sylvian aqueduct, using CINE-PC and RT-PC. CINE-PC uses 32 velocity maps to represent dynamic CSF flow over an average cardiac cycle, while RT-PC continuously quantifies CSF flow over 45-seconds. Free-breathing signals were recorded from 25 participants. RT-PC signal was segmented into independent cardiac cycle flow curves (Q t ) and reconstructed into an averaged Q t . To assess RT-PC's accuracy, parameters such as segmented area, flow amplitude, and stroke volume (SV) of the reconstructed Q t from RT-PC were compared with those derived from the averaged Q t generated by CINE-PC. The breathing signal was used to categorize the Q t into expiratory or inspiratory phases, enabling the reconstruction of two Q t for inspiration and expiration. The breathing effects on various CSF parameters can be quantified by comparing these two reconstructed Qt., Results: RT-PC overestimated CSF area (82.7% at aqueduct, 11.5% at C2-C3) compared to CINE-PC. Stroke volumes for CINE-PC were 615 mm³ (aqueduct) and 43 mm³ (spinal), and 581 mm³ (aqueduct) and 46 mm³ (spinal) for RT-PC. During thoracic pressure increase, spinal CSF net flow, flow amplitude, SV, and cardiac period increased by 6.3%, 6.8%, 14%, and 6%, respectively. Breathing effects on net flow showed a significant phase difference compared to the other parameters. Aqueduct-CSF flows were more affected by breathing than spinal-CSF., Conclusions: RT-PC accurately quantifies CSF oscillations in real-time and eliminates the need for cardiac synchronization, enabling the quantification of the cardiac and breathing components of CSF flow. This study quantifies the impact of free-breathing on CSF parameters, offering valuable physiological references for understanding the effects of breathing on CSF dynamics., (© 2024. The Author(s).)

Quantifying the effects of free breathing on cerebral venous flow is crucial for understanding cerebral circulation mechanisms and clinical applications. Unlike conventional cine phase-contrast MRI sequences (CINE-PC), real-time phase-contrast MRI sequences (RT-PC) can provide a continuous beat-to-beat flow signal that makes it possible to quantify the effect of breathing on cerebral venous flow. In this study, we examined 28 healthy human participants, comprising of 14 males and 14 females. Blood flows in the right/left internal jugular veins in the extracranial plane and the superior sagittal sinus (SSS) and straight sinus in the intercranial plane were quantified using CINE-PC and RT-PC. The first objective of this study was to determine the accuracy of RT-PC in quantifying cerebral venous flow, relative to CINE-PC. The second, and main objective, was to quantify the effect of free breathing on cerebral venous flow, using a time-domain multiparameter analysis method. Our results showed that RT-PC can accurately quantify cerebral venous flow with a 2 × 2 mm 2 spatial resolution and 75 ms/image time resolution. The mean flow rate, amplitude, stroke volume, and cardiac period of cerebral veins were significantly higher from the mid-end phase of expiration to the mid-end phase of inspiration. Breathing affected the mean flow rates in the jugular veins more than those in the SSS and straight sinus. Furthermore, the effects of free breathing on the flow rate of the left and right jugular veins were not synchronous. These new findings provide a useful reference for better understanding the mechanisms of cerebral circulation., (Copyright © 2024 the authors.)

Objectives: The PRECISE criteria for serial multiparametric magnetic resonance imaging (MRI) of the prostate during active surveillance recommend the use of a dedicated scoring system (PRECISE score) to assess the likelihood of clinically significant radiological change. This pilot study assesses the effect of an interactive teaching course on prostate MRI during active surveillance in assessing radiological change in serial imaging., Methods: Eleven radiology fellows and registrars with different experience in prostate MRI reading participated in a dedicated teaching course where they initially evaluated radiological change (based on their previous training in prostate MRI reading) independently in fifteen patients on active surveillance (baseline and follow-up scan), and then attended a lecture on the PRECISE score. The initial scans were reviewed for teaching purposes and afterwards the participants re-assessed the degree of radiological change in a new set of images (from fifteen different patients) applying the PRECISE score. Receiver operating characteristic analysis was performed. Confirmatory biopsies and PRECISE scores given in consensus by two radiologists (involved in the original draft of the PRECISE score) were the reference standard., Results: There was a significant improvement in the average area under the curve (AUC) for the assessment of radiological change from baseline (AUC: 0.60 [Confidence Intervals: 0.51-0.69] to post-teaching (AUC: 0.77 [0.70-0.84]). This was an improvement of 0.17 [0.016-0.28] (p = 0.004)., Conclusions: A dedicated teaching course on the use of the PRECISE score improves the accuracy in the assessment of radiological change in serial MRI of the prostate., (© 2022. The Author(s).)

Emissions of diesel exhaust gas in confined work environments are a major health and safety concern, because of exposition to nitrogen oxides (NO x ). Removal of these pollutants from exhaust gas calls for engineering of an optimum sorbent for the selective trapping of NO and NO 2 in the presence of water. To this end, periodic density functional theory calculations along with a recent dispersion correction scheme, namely the Tkatchenko-Scheffler scheme coupled with iterative Hirshfeld partitioning TS/HI, were performed to investigate the interactions between NO, NO 2 , H 2 O and a series of divalent cation (Be 2+ , Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ , Fe 2+ , Cu 2+ , Zn 2+ , Pd 2+ , and Pt 2+ ) faujasites. This enabled the identification of the optimum zeolites to selectively capture NO x in the presence of H 2 O, with respect to two important criteria, such as thermodynamic affinity and regeneration. Our results revealed that Pt 2+ and Pd 2+ containing faujasites are the best candidates for effective capture of both NO and NO 2 molecules, which paves the way towards the use of these sorbents to address this challenging application.

Coronavirus disease 2019 (COVID-19) emerged in 2019 and disseminated around the world rapidly. Computed tomography (CT) imaging has been proven to be an important tool for screening, disease quantification and staging. The latter is of extreme importance for organizational anticipation (availability of intensive care unit beds, patient management planning) as well as to accelerate drug development through rapid, reproducible and quantified assessment of treatment response. Even if currently there are no specific guidelines for the staging of the patients, CT together with some clinical and biological biomarkers are used. In this study, we collected a multi-center cohort and we investigated the use of medical imaging and artificial intelligence for disease quantification, staging and outcome prediction. Our approach relies on automatic deep learning-based disease quantification using an ensemble of architectures, and a data-driven consensus for the staging and outcome prediction of the patients fusing imaging biomarkers with clinical and biological attributes. Highly promising results on multiple external/independent evaluation cohorts as well as comparisons with expert human readers demonstrate the potentials of our approach., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Author(s). Published by Elsevier B.V. All rights reserved.)

Introduction: Covid-19 pneumonia CT extent correlates well with outcome including mortality. However, CT is not widely available in many countries. This study aimed to explore the relationship between Covid-19 pneumonia CT extent and blood tests variations. The objective was to determine for the biological variables correlating with disease severity the cut-off values showing the best performance to predict the parenchymal extent of the pneumonia., Methods: Bivariate correlations were calculated between biological variables and grade of disease extent on CT. Receiving Operating Characteristic curve analysis determined the best cutoffs for the strongest correlated biological variables. The performance of these variables to predict mild (<10%) or severe pneumonia (>50% of parenchyma involved) was evaluated., Results: Correlations between biological variables and disease extent was evaluated in 168 patients included in this study. LDH, lymphocyte count and CRP showed the strongest correlations (with 0.67, -0.41 and 0.52 correlation coefficient, respectively). Patients were split into a training and a validation cohort according to their centers. If one variable was above/below the following cut-offs, LDH>380, CRP>80 or lymphocyte count <0.8G/L, severe pneumonia extent on CT was detected with 100% sensitivity. Values above/below all three thresholds were denoted in 73% of patients with severe pneumonia extent. The combination of LDH<220 and CRP<22 was associated with mild pneumonia extent (<10%) with specificity of 100%., Discussion: LDH showed the strongest correlation with the extent of Covid-19 pneumonia on CT. Combined with CRP±lymphocyte count, it helps predicting parenchymal extent of the pneumonia when CT scan is not available., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objectives: Low-pressure carburising is a new technology used to harden steel; the process has been shown to be a source of considerable polycyclic aromatic hydrocarbons (PAH) pollution. Some PAH are carcinogenic, and activities such as furnace maintenance may thus represent a risk to workers. Occupational exposure during these operations should therefore be assessed., Methods: In this study, the PAH-related carcinogenic risk associated with furnace maintenance was assessed by monitoring atmospheric levels of benzo[a]pyrene (BaP), a representative marker, alongside urinary levels of 3-hydroxybenzo[a]pyrene (3-OHBaP), one of its metabolites. PAH exposure levels were monitored during seven sampling campaigns in four different factories specialized in heat-treatment of mechanical workpieces for the automotive and helicopter industries. Two types of furnace were studied, and 37 individuals were monitored., Results: Values up to 20-fold the French regulatory value of 150 ng/m3 for atmospheric BaP, and, for urinary 3-OHBaP values up to 40-fold the French biological limit value (BLV) of 0.35 nmol/mol of creatinine were detected. Very high concentrations of BaP, close to or even exceeding those found in coal-tar pitch (up to about 20 g/kg), were measured in residues (tars, dusts) deposited inside the furnace. Even when adequate and suitable personal protective equipment was used, urinary 3-OHBaP values often exceeded the BLV. We hypothesize that this exposure is linked to insidious and fortuitous dermal contamination through contact with factory equipment and staining., (© The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.)