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Contribution: The evaluation of analog-to-digital conversion methods constitutes a key component of an Instrumentation course. This study introduces an affordable educational platform based on Arduino UNO board designed for teaching analog-to-digital conversion concepts, supported by virtual instruments (VIs). Background: ADCs are electronic devices found in a wide range of consumer electronics, such as smartphones and Internet of Things (IoT) devices. In order to investigate the fundamental aspects of ADCs, a data acquisition system is required. However, high-quality ADC systems tend to be expensive. Alternatively, cost-effective microcontrollers can serve as an educational platform for conducting experimental procedures, including tests, characterization, and calibration. Intended Outcomes: The proposed experiment concentrates on elucidating the theoretical foundations of analog-to-digital conversion, along with providing in-depth insights into the technical details involved in characterizing and calibrating ADCs. Application Design: Four VIs have been developed and are employed to investigate concepts, such as resolution, nonlinearity, aliasing, and to determine offset and gain errors. Findings: The learning experience and the usability of the system were assessed through questionnaires distributed to a total of 105 students. In addition, the final exam was used to assess the performance of 29 students. The results indicate that the students significantly improved their ability to understand, apply, and analyze essential aspects of ADC after engaging in the experiments, demonstrating substantial learning gains.

The chemical composition and physical properties of secondary organic aerosol (SOA) generated through OH-initiated oxidation of mixtures containing β-myrcene, an acyclic monoterpene, and d-limonene, a cyclic monoterpene, were investigated to assess the extent of the chemical interactions between their oxidation products. The SOA samples were prepared in an environmental smog chamber, and their composition was analyzed offline using ultraperformance liquid chromatography coupled with electrospray ionization high-resolution mass spectrometry (UPLC-ESI-HRMS). Our results suggested that SOA containing β-myrcene showed a higher proportion of oligomeric compounds with low volatility compared to that of SOA from d-limonene. The formula distribution and signal intensities of the mixed SOA could be accurately predicted by a linear combination of the mass spectra of the SOA from individual precursors. Effects of cross-reactions were observed in the distribution of isomeric oxidation products within the mixed SOA, as made evident by chromatographic analysis. On the whole, β-myrcene and d-limonene appear to undergo oxidation by OH largely independently from each other, with only subtle effects from cross-reactions influencing the yields of specific oxidation products.

Secondary organic aerosol (SOA) derived from n-alkanes, as emitted from vehicles and volatile chemical products, is a major component of anthropogenic particulate matter, yet the chemical composition and phase state are poorly understood and thus poorly constrained in aerosol models. Here we provide a comprehensive analysis of n-alkane SOA by explicit gas-phase chemistry modeling, machine learning, and laboratory experiments to show that n-alkane SOA adopts low-viscous semi-solid or liquid states. Our study underlines the complex interplay of molecular composition and SOA viscosity: n-alkane SOA with a higher carbon number mostly consists of less functionalized first-generation products with lower viscosity, while the SOA with a lower carbon number contains more functionalized multigenerational products with higher viscosity. This study opens up a new avenue for analysis of SOA processes, and the results indicate few kinetic limitations of mass accommodation in SOA formation, supporting the application of equilibrium partitioning for simulating n-alkane SOA formation in large-scale atmospheric models.

Reactive oxygen species (ROS) and environmentally persistent free radicals (EPFR) play an important role in chemical transformation of atmospheric aerosols and adverse aerosol health effects. This study investigated the effects of nitrogen oxides (NOx) during photooxidation of α-pinene and naphthalene on the EPFR content and ROS formation from secondary organic aerosols (SOA). Electron paramagnetic resonance (EPR) spectroscopy was applied to quantify EPFR content and ROS formation. While no EPFR were detected in α-pinene SOA, we found that naphthalene SOA contained about 0.7 pmol μg-1 of EPFR, and NOx has little influence on EPFR concentrations and oxidative potential. α-Pinene and naphthalene SOA generated under low NOx conditions form OH radicals and superoxide in the aqueous phase, which was lowered substantially by 50-80% for SOA generated under high NOx conditions. High-resolution mass spectrometry analysis showed the substantial formation of nitroaromatics and organic nitrates in a high NOx environment. The modeling results using the GECKO-A model that simulates explicit gas-phase chemistry and the radical 2D-VBS model that treats autoxidation predicted reduced formation of hydroperoxides and enhanced formation of organic nitrates under high NOx due to the reactions of peroxy radicals with NOx instead of their reactions with HO2. Consistently, the presence of NOx resulted in the decrease of peroxide contents and oxidative potential of α-pinene SOA.

Introduction: Patients with ischemic stroke (IS) and atrial fibrillation (AF) face a higher risk of recurrent vascular events. This study evaluates the impact of atherosclerotic vascular disease burden across different vascular territories on the risk of vascular events in patients with recent ischemic stroke and AF within 90 days. Patients and Methods: We included patients with IS and AF from the International RAF network in a prospective 90-day follow-up. Atherosclerotic vascular disease was identified by at least one of the following: Symptomatic ischemic heart disease, symptomatic peripheral artery disease, internal carotid stenosis ≥50%, or the presence of plaques in the aorta. The primary outcome was a composite of stroke, transient ischemic attack, systemic embolism, cerebral bleeding, and major extracranial bleeding within 90 days postacute stroke. Patients were categorized into 5 groups based on the number of affected atherosclerotic vascular territories, with those with no atherosclerotic vascular disease as the reference. Kaplan–Meier curves were generated and compared using the log-rank test to determine the predictive value of the number of diseased territories for the risk of events. Data analysis was performed with SPSS/PC Win Package 25.0. Results: Of the 2148 patients (mean age 77.59; 53.86% female), 744 (34.60%) had atherosclerosis. Multivariable analysis revealed that involvement of 3 (hazard ratio [HR] 2.80, 95% confidence interval [CI]: 1.20-6.53) or 4 (HR 6.81, 95% CI: 1.02-36.24) vascular territories was significantly associated with the risk of combined events. Conclusions: In patients with recent ischemic stroke and AF, atherosclerosis across multiple territories correlates with a higher risk of future vascular events.

OpenFOAM is a CFD software widely used in both industry and academia. The exaFOAM project aims at enhancing the HPC scalability of OpenFOAM, while identifying its current bottlenecks and proposing ways to overcome them. For the assessment of the software components and the code profiling during the code development, lightweight but significant benchmarks should be used. The answer was to develop microbenchmarks, with a small memory footprint and short runtime. The name microbenchmark does not mean that they have been prepared to be the smallest possible test cases, as they have been developed to fit in a compute node, which usually has dozens of compute cores. The microbenchmarks cover a broad band of applications: incompressible and compressible flow, combustion, viscoelastic flow and adjoint optimization. All benchmarks are part of the OpenFOAM HPC Technical Committee repository and are fully accessible. The performance using HPC systems with Intel and AMD processors (x86_64 architecture) and Arm processors (aarch64 architecture) have been benchmarked. For the workloads in this study, the mean performance with the AMD CPU is 62% higher than with Arm and 42% higher than with Intel. The AMD processor seems particularly suited resulting in an overall shorter time-to-solution.

This paper presents the ERC StG project Venice’s Nissology (VeNiss), a semantic geo-spatial web infrastructure for reconstructing over five-centuries of transformations of Venice’s lagoon islands, alongside their interwoven relationships in a geographically- and temporally-based digital environment. VeNiss constitutes the first analytical methodology for investigating, interpreting, and visualising, through computational media, the connective dynamics of centre-periphery relations in historic settlements, with specific reference to archipelagoes. Through a transdisciplinary approach, which combines history, architecture, art history, social studies, and advanced digital technologies the research infrastructure enables the intersection of historical data with georeferenced maps, 2D reconstructions, and 3D interoperable models to express the urban processes that shaped the lagoon city from the sixteenth century.

Secondary organic aerosols (SOA) are major components of atmospheric fine particulate matter, affecting climate and air quality. Mounting evidence exists that SOA can adopt glassy and viscous semisolid states, impacting formation and partitioning of SOA. In this study, we apply the GECKO-A (Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere) model to conduct explicit chemical modeling of isoprene photooxidation and α-pinene ozonolysis and their subsequent SOA formation. The detailed gas-phase chemical schemes from GECKO-A are implemented into a box model and coupled to our recently developed glass transition temperature parameterizations, allowing us to predict SOA viscosity. The effects of chemical composition, relative humidity, mass loadings and mass accommodation on particle viscosity are investigated in comparison with measurements of SOA viscosity. The simulated viscosity of isoprene SOA agrees well with viscosity measurements as a function of relative humidity, while the model underestimates viscosity of α-pinene SOA by a few orders of magnitude. This difference may be due to missing processes in the model, including autoxidation and particle-phase reactions, leading to the formation of high-molar-mass compounds that would increase particle viscosity. Additional simulations imply that kinetic limitations of bulk diffusion and reduction in mass accommodation coefficient may play a role in enhancing particle viscosity by suppressing condensation of semi-volatile compounds. The developed model is a useful tool for analysis and investigation of the interplay among gas-phase reactions, particle chemical composition and SOA phase state.

In the historiography of Venice little attention has so far been given to the representation of lagoon settlements, which for centuries were of signal importance within the political, socio-economic, and cultural layouts of the Republic. Since the late Middle Ages, these spaces had housed a rich cluster of religious institutions; then, reforms and post-Tridentine tensions led to serious conflicts around issues of ecclesiastical and secular jurisdiction over land and water possessions. Between the sixteenth and seventeenth centuries, government authorities built numerous utilities and collective infrastructures inside the lagoon cloisters – such as boathouses, guest houses, gunpowder magazines, and hospitals – thus increasingly expanding state control over the life of the religious communities. These building projects gave rise to a significant corpus of maps, surveys, and land measurements, which today allow scholars to assess not only the quantity but also the different degrees of the Republic’s interventions, which ranged from simple maintenance projects to the complete reorganization of certain islands. Though highly technical, these sources represent a fundamental vehicle and model of knowledge for interpreting the Venetian basin. The realities they suggest are very different from what is conveyed by official cartography, shaped as it is by the need for laudes civitatum. By looking at this corpus we may better understand the value of the lagoon settlements as constitutive and connective elements of the urban fabric.

Purpose: We studied the relationship between job engagement and systematic problem solving (SPS) among shop-floor employees and how lean production (LP) and Internet of Things (IoT) systems moderate this relationship. Design/methodology/approach: We collected data from a sample of 440 shop floor workers in 101 manufacturing work units across 33 plants. Because our data is nested, we employed a series of multilevel regression models to test the hypotheses. The application of IoT systems within work units was evaluated by our research team through direct observations from on-site visits. Findings: Our findings indicate a positive association between job engagement and SPS. Additionally, we found that the adoption of lean bundles positively moderates this relationship, while, surprisingly, the adoption of IoT systems negatively moderates this relationship. Interestingly, we found that, when the adoption of IoT systems is complemented by a lean management system, workers tend to experience a higher effect on the SPS of their engagement. Research limitations/implications: One limitation of this research is the reliance on the self-reported data collected from both workers (job engagement, SPS and control variables) and supervisors (lean bundles). Furthermore, our study was conducted in a specific country, Italy, which might have limitations on the generalizability of the results since cross-cultural differences in job engagement and SPS have been documented. Practical implications: Our findings highlight that employees' strong engagement in SPS behaviors is shaped by the managerial and technological systems implemented on the shop floor. Specifically, we point out that implementing IoT systems without the appropriate managerial practices can pose challenges to fostering employee engagement and SPS. Originality/value: This paper provides new insights on how lean and new technologies contribute to the development of learning-to-learn capabilities at the individual level by empirically analyzing the moderating effects of IoT systems and LP on the relationship between job engagement and SPS. [ABSTRACT FROM AUTHOR]

The photochemical box model CiTTyCAT is used to analyse the absence of oxygen mass-independent anomalies (O-MIF) in volcanic sulfates produced in the troposphere. An aqueous sulfur oxidation module is implemented in the model and coupled to an oxygen isotopic scheme describing the transfer of O-MIF during the oxidation of SO2 by OH in the gas-phase, and by H2O2, O3 and O2 catalysed by TMI in the liquid phase. Multiple model simulations are performed in order to explore the relative importance of the various oxidation pathways for a range of plausible conditions in volcanic plumes. Note that the chemical conditions prevailing in dense volcanic plumes are radically different from those prevailing in the surrounding background air. The first salient finding is that, according to model calculations, OH is expected to carry a very significant O-MIF in sulfur-rich volcanic plumes and, hence, that the volcanic sulfate produced in the gas phase would have a very significant positive isotopic enrichment. The second finding is that, although H2O2 is a major oxidant of SO2 throughout the troposphere, it is very rapidly consumed in sulfur-rich volcanic plumes. As a result, H2O2 is found to be a minor oxidant for volcanic SO2. According to the simulations, oxidation of SO2 by O3 is negligible because volcanic aqueous phases are too acidic. The model predictions of minor or negligible sulfur oxidation by H2O2 and O3, two oxidants carrying large O-MIF, are consistent with the absence of O-MIF seen in most isotopic measurements of volcanic tropospheric sulfate. The third finding is that oxidation by O2∕TMI in volcanic plumes could be very substantial and, in some cases, dominant, notably because the rates of SO2 oxidation by OH, H2O2 and O3 are vastly reduced in a volcanic plume compared to the background air. Only cases where sulfur oxidation by O2∕TMI is very dominant can explain the isotopic composition of volcanic tropospheric sulfate.

Abstract Background Based on meta-analyses results, it is currently acknowledged that there is an increased risk of pneumonia in patients with chronic obstructive pulmonary disease (COPD) undergoing inhaled corticosteroids (ICS) treatment. However, this is not found to be true in those with asthma. No data on this risk are available for COPD patients involved in pulmonary rehabilitation program (PR). Methods For 1 year, we prospectively studied 2 cohorts of COPD patients—undergoing PR and not undergoing PR. The first group included 438 patients undergoing PR of which 353 were treated with ICS, and 85 were treated with bronchodilators only. The second group was comprised of 76 COPD patients who were treated with ICS, but not PR. The control group consisted of 49 ICS-treated patients with asthma. The diagnosis of pneumonia, when suspected, had to be confirmed with a chest x-ray. Results Overall, 6 cases of pneumonia were diagnosed in the first study group: 5 ICS-treated patients and 1 patient treated only with bronchodilators. This corresponded to a rate of 1.41 and 1.17%, respectively, compared to a rate of 6.6% in COPD patients not treated with PR, which was significantly higher (p = 0.029) than that in the first study group. No case of pneumonia was registered among patients with asthma. Conclusions These findings suggest that a significantly lower incidence of pneumonia is found in COPD patients treated with ICS and PR than in patients treated with ICS but not with PR. This observation deserves to be investigated in large populations of PR-treated COPD patients, possibly in multi-centric cohort studies.