174 research outputs found

    Wind-tunnel measurements of the airflow pattern above the collector of different shielded and unshielded precipitation gauges.

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    Wind is the first environmental source of precipitation undercatch for catching-type precipitation gauge. This work presents an aerodynamic investigation on different precipitation gauge geometries and on a wind shield by means of wind tunnel tests. Experiments have been jointly performed by University of Genoa, DICCA, and Politecnico di Milano within the Italian project PRIN 20154WX5NA \u201cReconciling precipitation with runoff: the role of understated measurement biases in the modelling of hydrological processes\u201d. The airflow, around precipitation gauges, was measured employing two different experimental techniques: a traversing system equipped with \u201cCobra\u201d multi hole pressure probes and the Particles Image Velocimetry PIV. Cobra probes allow to measure the three components of the local flow velocity in the measuring points, while PIV technique provides two-dimensional velocity fields on the investigated planes. The airflow velocity and direction were investigated for different wind speed values and different precipitation gauge geometries: the \u201cchimney\u201d, the \u201ccylindrical\u201d and the \u201cinverted conical\u201d shapes. The effect of a traditional Single Alter windshield was also assessed on the cylindrical shape. These experiments allow to detect qualitatively and quantitatively the main features of the flow, speed-up and updraft, above the collector which influence the particle trajectories and their collection. Results confirm the dependency of the airflow disturbance on the gauge geometry, especially in terms of maximum local velocity and distribution of the upward and downward components of the vertical velocity. PIV velocity fields and Cobra velocity profiles show the expected attenuation of the flow velocity above a gauge located inside the windshield due to the break of the flow induced by the shield slats. The experimental campaign provided a wide dataset suitable for the validation of numerical Computational Fluid Dynamics simulations. This work is propaedeutic to the quantification of the precipitation undercatch and the elaboration of correction curves to obtain the actual precipitation in windy conditions

    Argument mining as rapid screening tool of COVID-19 literature quality: Preliminary evidence

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    BackgroundThe COVID-19 pandemic prompted the scientific community to share timely evidence, also in the form of pre-printed papers, not peer reviewed yet.PurposeTo develop an artificial intelligence system for the analysis of the scientific literature by leveraging on recent developments in the field of Argument Mining.MethodologyScientific quality criteria were borrowed from two selected Cochrane systematic reviews. Four independent reviewers gave a blind evaluation on a 1–5 scale to 40 papers for each review. These scores were matched with the automatic analysis performed by an AM system named MARGOT, which detected claims and supporting evidence for the cited papers. Outcomes were evaluated with inter-rater indices (Cohen's Kappa, Krippendorff's Alpha, s* statistics).ResultsMARGOT performs differently on the two selected Cochrane reviews: the inter-rater indices show a fair-to-moderate agreement of the most relevant MARGOT metrics both with Cochrane and the skilled interval scores, with larger values for one of the two reviews.Discussion and conclusionsThe noted discrepancy could rely on a limitation of the MARGOT system that can be improved; yet, the level of agreement between human reviewers also suggests a different complexity between the two reviews in debating controversial arguments. These preliminary results encourage to expand and deepen the investigation to other topics and a larger number of highly specialized reviewers, to reduce uncertainty in the evaluation process, thus supporting the retraining of AM systems

    Surgical and survival outcomes with perioperative or neoadjuvant immune-checkpoint inhibitors combined with platinum-based chemotherapy in resectable NSCLC: A systematic review and meta-analysis of randomised clinical trials

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    : The use of neoadjuvant or perioperative anti-PD(L)1 was recently tested in multiple clinical trials. We performed a systematic review and meta-analysis of randomised trials comparing neoadjuvant or perioperative chemoimmunotherapy to neoadjuvant chemotherapy in resectable NSCLC. Nine reports from 6 studies were included. Receipt of surgery was more frequent in the experimental arm (odds ratio, OR 1.39) as was pCR (OR 7.60). EFS was improved in the experimental arm (hazard ratio, HR 0.55) regardless of stage, histology, PD-L1 expression (PD-L1 negative, HR 0.74) and smoking exposure (never smokers, HR 0.67), as was OS (HR 0.67). Grade > = 3 treatment-related adverse events were more frequent in the experimental arm (OR 1.22). The experimental treatment improved surgical outcomes, pCR rates, EFS and OS in stage II-IIIB, EGFR/ALK negative resectable NSCLC; confirmatory evidence is warranted for stage IIIB tumours and with higher maturity of the OS endpoint

    Data-driven optimization of search service composition for answering multi-domain queries

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    Answering multi-domain queries requires the combination of knowledge from various domains. Such queries are inadequately answered by general-purpose search engines, because domain- specific systems typically exhibit sophisticated knowledge about their own fields of expertise. Moreover, multi-domain queries typically require combining in the result domain knowledge possibly coming from multiple web resources, therefore conventional crawling and indexing techniques, based on individual pages, are not adequate. In this paper we present a conceptual framework for addressing the composition of search services for solving multi-domain queries. The approach consists in building an infrastructure for search service composition that leaves within each search system the responsibility of maintaining and improving its domain knowledge, and whose main challenge is to provide the “glue” between them; such glue is expressed in the format of joins upon search service results, and for this feature we regard our approach as “data-driven”. We present an overall architecture, and the work that has been done so far in the development of some of the main modules.publishe

    Integrated Genomic, Functional, and Prognostic Characterization of Atypical Chronic Myeloid Leukemia

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    Atypical chronic myeloid leukemia (aCML) is a BCR-ABL1-negative clonal disorder, which belongs to the myelodysplastic/myeloproliferative group. This disease is characterized by recurrent somatic mutations in SETBP1, ASXL1 and ETNK1 genes, as well as high genetic heterogeneity, thus posing a great therapeutic challenge. To provide a comprehensive genomic characterization of aCML we applied a high-throughput sequencing strategy to 43 aCML samples, including both whole-exome and RNA-sequencing data. Our dataset identifies ASXL1, SETBP1, and ETNK1 as the most frequently mutated genes with a total of 43.2%, 29.7 and 16.2%, respectively. We characterized the clonal architecture of 7 aCML patients by means of colony assays and targeted resequencing. The results indicate that ETNK1 variants occur early in the clonal evolution history of aCML, while SETBP1 mutations often represent a late event. The presence of actionable mutations conferred both ex vivo and in vivo sensitivity to specific inhibitors with evidence of strong in vitro synergism in case of multiple targeting. In one patient, a clinical response was obtained. Stratification based on RNA-sequencing identified two different populations in terms of overall survival, and differential gene expression analysis identified 38 significantly overexpressed genes in the worse outcome group. Three genes correctly classified patients for overall survival
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