Effect of Process Parameters on Laser Powder Bed Fusion of Al-Sn Miscibility Gap Alloy

Al-Sn binary system is a miscibility gap alloy consisting of an Al-rich phase and a Sn-rich phase. This system is traditionally applied in bearings and more recently found application as form-stable phase change material (PCM) exploiting solid-liquid phase transition of Sn. A careful choice of production process is required to avoid macro-segregation of the two phases, which have different densities and melting temperatures. In the present study, the additive manufacturing process known as laser powder bed fusion (LPBF) was applied to an Al-Sn alloy with 20% volume of Sn, as a rapid solidification process. The effect of process parameters on microstructure and hardness was evaluated. Moreover, feasibility and stability with thermal cycles of a lattice structure of the same alloy were experimentally investigated. An Al-Sn lattice structure could be used as container for a lower melting organic PCM (e.g., a paraffin or a fatty acid), providing high thermal diffusivity thanks to the metallic network and a "safety system" reducing thermal diffusivity if the system temperature overcomes Sn melting temperature. Even if focused on Al-Sn to be applied in thermal management systems, the study offers a contribution in view of the optimization of manufacturing processes locally involving high solidification rates and reheat cycles in other miscibility gap alloys (e.g., Fe-Cu) with similar thermal or structural applications

Tailoring parameter distributions to specific germplasm : impact on crop model-based ideotyping

Crop models are increasingly used to identify promising ideotypes for given environmental and management conditions. However, uncertainty must be properly managed to maximize the in vivo realizability of ideotypes. We focused on the impact of adopting germplasm-specific distributions while exploring potential combinations of traits. A field experiment was conducted on 43 Italian rice varieties representative of the Italian rice germplasm, where the following traits were measured: light extinction coefficient, radiation use efficiency, specific leaf area at emergence and tillering. Data were used to derive germplasm-specific distributions, which were used to re-run a previous modelling experiment aimed at identifying optimal combinations of plant trait values. The analysis, performed using the rice model WARM and sensitivity analysis techniques, was conducted under current conditions and climate change scenarios. Results revealed that the adoption of germplasm-specific distributions may markedly affect ideotyping, especially for the identification of most promising traits. A re-ranking of some of the most relevant parameters was observed (radiation use efficiency shifted from 4th to 1st), without clear relationships between changes in rankings and differences in distributions for single traits. Ideotype profiles (i.e., values of the ideotype traits) were instead more consistent, although differences in trait values were found

Trepan Reloaded: A Knowledge-driven Approach to Explaining Artificial Neural Networks

Explainability in Artificial Intelligence has been revived as a topic of active research by the need of conveying safety and trust to users in the `how' and `why' of automated decision-making. Whilst a plethora of approaches have been developed for post-hoc explainability, only a few focus on how to use domain knowledge, and how this influences the understandability of global explanations from the users' perspective. In this paper, we show how ontologies help the understandability of global post-hoc explanations, presented in the form of symbolic models. In particular, we build on Trepan, an algorithm that explains artificial neural networks by means of decision trees, and we extend it to include ontologies modeling domain knowledge in the process of generating explanations. We present the results of a user study that measures the understandability of decision trees using a syntactic complexity measure, and through time and accuracy of responses as well as reported user confidence and understandability. The user study considers domains where explanations are critical, namely, in finance and medicine. The results show that decision trees generated with our algorithm, taking into account domain knowledge, are more understandable than those generated by standard Trepan without the use of ontologies

Special Issue “Rheumatic Diseases: Pathophysiology, Targeted Therapy, Focus on Vascular and Pulmonary Manifestations 2022”

This Special Issue, titled "Rheumatic Diseases: Pathophysiology, Targeted Therapy, Focus on Vascular and Pulmonary Manifestations", aims to demonstrate recent and new advances and future trends in the field of rheumatic diseases [...]

Host-Based Treatments for Severe COVID-19

COVID-19 has been a global health problem since 2020. There are different spectrums of manifestation of this disease, ranging from asymptomatic to extremely severe forms requiring admission to intensive care units and life-support therapies, mainly due to severe pneumonia. The progressive understanding of this disease has allowed researchers and clinicians to implement different therapeutic alternatives, depending on both the severity of clinical involvement and the causative molecular mechanism that has been progressively explored. In this review, we analysed the main therapeutic options available to date based on modulating the host inflammatory response to SARS-CoV-2 infection in patients with severe and critical illness. Although current guidelines are moving toward a personalised treatment approach titrated on the timing of presentation, disease severity, and laboratory parameters, future research is needed to identify additional biomarkers that can anticipate the disease course and guide targeted interventions on an individual basis

Microvascular Alteration in COVID-19 Documented by Nailfold Capillaroscopy

COVID-19 is a multisystemic disease that mainly affects and causes dysregulation of the endothelium, causing systemic manifestations. A nailfold video capillaroscopy is a safe, easy, and noninvasive method to evaluate microcirculation alteration. In this review, we analyzed the literature available to date regarding the object of nailfold video capillaroscopy (NVC) use in patients with a SARS-CoV-2 infection, both in the acute phase and after discharge. The scientific evidence pointed out the main alterations in capillary circulation shown by NVC, so reviewing the findings of each article allowed us to define and analyze the future prospects and needs for possibly including NVC within the management of patients with COVID-19, both during and after the acute phase

Ce-exchange capacity of zeolite L in different cationic forms: a structural investigation

Cerium exchange by microporous materials, such as zeolites, has important applications in different fields, for example, rare earth element recovery from waste or catalytic processes. This work investigated the Ce-exchange capacity of zeolite L in three different cationic forms (the as-synthesized K form and Naand NH4-exchanged ones) from a highly concentrated solution. Chemical analyses and structural investigations allowed determination of the mechanisms involved in the exchanges and give new insights into the interactions occurring between the cations and the zeolite framework. Different cation sites are involved: (i) K present in the original LTL in the cancrinite cage (site KB) cannot be exchanged; (ii) the cations in KD (in the 12-membered ring channel) are always exchanged; while (iii) site KC (in the eight-membered ring channel) is involved only when K+ is substituted by NH4+, thus promoting a higher exchange rate for NH4+ -> K+ than for Na+ -> K+. In the Ce-exchanged samples, a new site occupied by Ce appears in the centre of the main channel, accompanied by an increase in the number of and a rearrangement of H2O molecules. In terms of Ce exchange, the three cationic forms behave similarly, from both the chemical and structural point of view (exchanged Ce ranges from 38 to 42% of the pristine cation amount). Beyond the intrinsic structural properties of the zeolite L framework, the Ce exchange seems thus also governed by the water coordination sphere of the cation. Complete Ce recovery from zeolite pores was achieved

Editorial: Evolution in respiratory pharmacology

This collection of Research Topics entitled “Evolution in respiratory pharmacology,” involving authors from several countries, confirms that “Respiratory Pharmacology” is a current topic in clinical and research settings. All articles focused on contributions that explore the changing context and emerging new perspectives within Respiratory Pharmacology (Kim et al., Cerqua et al., Li et al., Lin et al., Zhang et al.). The emphasis of this Research Topic is on the dynamics of change and the evolution of the latest progress made in the field of Respiratory Pharmacology. This collection of articles aims to inform, inspire, and provide direction and guidance to researchers in the field

Analysis and modeling of processes involved with salt tolerance and rice

Salinity is a worldwide problem for rice (Oryza sativa L.) cultivation, and a number of breeding programs targeting increased salt tolerance are ongoing. A new trait-based mathematical model for salt stress on rice was recently proposed, characterized by a high level of detail in the description of physiological mechanisms dealing with crop response to salinity. In this study, dedicated growth chamber experiments were performed where three rice cultivars with different degrees of tolerance were grown under different salinity levels. The aim was to improve the understanding of physiological mechanisms like Na+ uptake and sequestration in structural tissues, and to validate the model using new datasets where temporal dynamics in plant response to salt stress were analyzed. Model evaluation demonstrated strong agreement between measured and simulated dry weights of plant organs (e.g., R2 = 0.88-0.97 for aboveground biomass), [Na+] in plant tissues (R2 = 0.73-0.88), and green leaf area index (R2 = 0.71-0.99). These results demonstrate the reliability of the model and support its adoption within studies aimed at analyzing or predicting the response of different cultivars to temporal dynamics of Na+ concentration in soil and water

Functional Progression after Dose Suspension or Discontinuation of Nintedanib in Idiopathic Pulmonary Fibrosis: A Real-Life Multicentre Study

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial lung disease with rapidly progressive evolution and an unfavorable outcome. Nintedanib (NTD) is an antifibrotic drug that has been shown to be effective in slowing down the progression of the disease. The aim of our study was to examine the efficacy, especially in terms of the functional decline, and the safety profile of NTD in patients treated with the recommended dose and subjects who reduced or suspended the therapy due to the occurrence of adverse reactions. Methods: We conducted a real-life retrospective study based on the experience of NTD use in two centers between 2015 and 2022. Clinical data were evaluated at baseline, at 6 and 12 months after the NTD introduction in the whole population and in subgroups of patients who continued the full-dose treatment, at a reduced dosage, and at the discontinuation of treatment. The following data were recorded: the demographic features, IPF clinical features, NTD therapeutic dosage, tolerability and adverse events, pulmonary function tests (PFTs), the duration of treatment upon discontinuation, and the causes of interruption. Results: There were 54 IPF patients who were included (29.6% females, with a median (IQR) age at baseline of 75 (69.0-79.0) years). Twelve months after the introduction of the NTD therapy, 20 (37%) patients were still taking the full dose, 11 (20.4%) had reduced it to 200 mg daily, and 15 (27.8%) had stopped treatment. Gastrointestinal intolerance predominantly led to the dose reduction (13.0%) and treatment cessation (20.4%). There were two deaths within the initial 6 months (3.7%) and seven (13.0%) within 12 months. Compared to the baseline, the results of the PFTs remained stable at 6 and 12 months for the entire NTD-treated population, except for a significant decline in the DLCO (% predicted value) at both 6 (38.0 ± 17.8 vs. 43.0 ± 26.0; p = 0.041) and 12 months (41.5 ± 15.3 vs. 44.0 ± 26.8; p = 0.048). The patients who continued treatment at the full dose or a reduced dosage showed no significant differences in the FVC and the DLCO at 12 months. Conversely, those discontinuing the NTD exhibited a statistically significant decline in the FVC (% predicted value) at 12 months compared to the baseline (55.0 ± 13.5 vs. 70.0 ± 23.0; p = 0.035). Conclusions: This study highlights the functional decline of the FVC at 12 months after the NTD initiation among patients discontinuing therapy but not among those reducing their dosage