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Traditional Extreme Value Statistics (EVS) applied to block maxima sampled anomalies of components produced by Laser-Powder Bed Fusion may produce important inaccuracies in the estimated characteristic defects. In fact, the typical presence of multiple defect types may significantly affect the fitted maxima distributions obtained from different sampling volumes. In this work, we show how the limitations of traditional EVS can be overcome by applying supervised machine learning (ML) algorithms to classify the defects before estimating the maxima distributions for each defect type. The ML-assisted EVS provided maxima distributions unaffected by the different sampling volumes. The obtained maxima distribution lead to robust estimates of exceedance curves and finally, by employing the Shiozawa curve, to robust fatigue strength predictions.

Several factors must be considered within the assessment of parts produced by Additive Manufacturing (AM) such as, for example, heterogeneous microstructure, process-induced defects, surface quality, residual stresses, and dependence on the material’s properties with the building orientation. All these factors severely affect the resistance to static and fatigue loadings of AMed components. Among the possible failure mechanisms, the failure promoted by static loadings when cracks are present is one of the most important failure conditions, in particular for the as-built parts, which might have reduced fracture toughness and ductility compared to the wrought alloy counterpart. In this work, we present a comprehensive approach to the static assessment of AlSi10Mg parts manufactured by Laser Powder Bed Fusion. Two benchmark fracture geometries were designed to investigate the typical AM geometrical features: i) thin walls in tension and ii) notched components in bending. Finite Element analyses of the benchmark specimens showed that an approach based on elastic–plastic fracture mechanics parameters is needed to correctly predict the experimental failures, despite the quasi-brittle behaviour shown by the AlSi10Mg alloy. In view of these results, this paper explores the applicability of the Failure Assessment Diagram (FAD), a tool used for conventional ductile materials, to static assessment of AMed parts. The results show that the assessment approach based on the FAD makes it possible to properly predict the experimental failures of the benchmark specimens.

Purpose: The aim of this study was to compare the diagnostic accuracy of magnetic resonance imaging (MRI) and dual-energy computed tomography (DECT) to identify residual-recurrent cholesteatoma using the second-look surgery as the reference standard., Methods: This prospective, institutional review board-approved study included 19 consecutive patients (11 males and 8 females; mean age of 62.2, range 34-80 years). Since five patients were studied bilaterally, a total of 24 ears were evaluated with DECT and MRI between February 2017 and June 2018. Any abnormal middle ear attenuation on high-resolution CT images (HRCT) or DECT color-coded maps, and any abnormal signal on MRI images was evaluated by four experienced radiologists. Diagnostic accuracy values of HRCT, DECT maps and CT numbers (by using receiver operator curves) and MRI were compared. Interobserver and intraobserver agreement were calculated., Results: Residual-recurrent cholesteatoma was diagnosed at surgery in 16/24 ears (66.6%). MRI and DECT revealed a total of 15/16 and 14/16 cholesteatomas, respectively. The sensitivity, specificity, PPV and NPV and accuracy of MRI and DECT were 93.7, 87.5, 93.7, 87.5, and 91.6% and 87.5, 87.5, 93.3, 87.5 and 87.5%, respectively. CT numbers were significantly different between positive (mean 57.6 HU, range - 65, 112 HU) and negative cases (mean 5.4 HU, range - 100, 66 HU) with p < 0.001. The interobserver and intraobserver agreement were k = 0.87 and k = 0.83, respectively., Conclusion: DECT may provide an accurate demonstration of residual-recurrent middle ear cholesteatoma.

Gerbera (Gerbera jamesonii Bolus) is one of the most popular ornamental flowers worldwide and used both as cut flower and potted plant. Some of them show excellent agronomic characters such as color, floral diameter, stem length, and vigor, which make this plant of commercial importance. Conventionally, multiplication is done through seeds or rhizome cuttings. Rapid multiplication of elite cultivars of Gerbera, with improved agronomic traits, has been achieved by using both direct and indirect tissue culture methods. Direct shoot regeneration was accomplished from stem apices on MS medium supplemented with 1 mg/L 6-benzyladenine (BA) and 1 mg/L kinetin. Indirect shoot induction succeeded from callus differentiation has been achieved on MS medium containing 2 mg/L 2,4-dichlorophenoxyacetic acid, 0.5 mg/L indole-3-acetic acid, and 2 mg/L BA. The in vitro shoots, 4-5 cm long, were rooted by quick dipping the shoot bases for 3-5 s in 2,000 mg/L indole-3-butyric acid solution followed by transfer to the pots containing farmyard manure, soil, and sand (1:1:1 by volume). Initially, in vitro plantlets were covered with glass jars to maintain a high relative humidity (85-90%). As soon as new shoot growth begins, relative humidity is decreased by exposing them to the open environmental conditions prior transferring to the glasshouse. Indirect shoot regeneration increased the frequency of somaclonal variations. The selected somaclones were used in developing new and novel cultivars.

The goal of our study was to estimate the presence (or absence) of latero-cervical nodal metastases (pN+), in patients with squamous oropharyngeal cancer, correlating this finding with T stage. We examined 255 patients out of 329 affected by squamous oropharyngeal cancer, from 1976 to 2005. The 255 patients examined were treated surgically (both T and N). As far as clinical latero-cervical nodal metastases were concerned, 215 patients (84%) were cN+, while 40% (16%) were cN-. The result of the histological examination showed that 82% of the neck dissections (both cN+ and cN-) actually had latero-cervical metastases, while the remaining patients had reactive lymph nodes. The false-positive (cN+ -->pN-) patients, were 14% while false-negative patients (cN- -->pN+) amounted to 63%. The correlation between T and pN+ of the patients classified as cN- showed that 24% of patients were T1, 44% T2, 32% T3, and none T4; the pN+ patients, who clinically manifested latero-cervical lymph-node metastases were: T1 8%, T2 15%, T3 37%, T4 40%. Analysis of these data led us to the conclusion that, in view of the high lymphophilia of squamous cancer in the oropharyngeal district, it would be advisable to treat N metastases, both cN+ and cN-, at any T stage of cancer, surgically or with chemo- or radiotherapy, according to the patient's performance status.