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The surgical treatment of the intermediate-risk DTC (1–4 cm) remains still controversial. We analyzed the current practice in Italy regarding the surgical management of intermediate-risk unilateral DTC to evaluate risk factors for recurrence and to identify a group of patients to whom propose a total thyroidectomy (TT) vs. hemithyroidectomy (HT). Among 1896 patients operated for thyroid cancer between January 2017 and December 2019, we evaluated 564 (29.7%) patients with unilateral intermediate-risk DTC (1–4 cm) without contralateral nodular lesions on the preoperative exams, chronic autoimmune thyroiditis, familiarity or radiance exposure. Data were collected retrospectively from the clinical register from 16 referral centers. The patients were followed for at least 14 months (median time 29.21 months). In our cohort 499 patients (88.4%) underwent total thyroidectomy whereas 65 patients (11.6%) underwent hemithyroidectomy. 151 (26.8%) patients had a multifocal DTC of whom 57 (10.1%) were bilateral. 21/66 (32.3%) patients were reoperated within 2 months from the first intervention (completion thyroidectomy). Three patients (3/564) developed regional lymph node recurrence 2 years after surgery and required a lymph nodal neck dissection. The single factor related to the risk of reoperation was the histological diameter (HR = 1.05 (1.00–1-09), p = 0.026). Risk stratification is the key to differentiating treatment options and achieving better outcomes. According to the present study, tumor diameter is a strong predictive risk factor to proper choose initial surgical management for intermediate‐risk DTC. [ABSTRACT FROM AUTHOR]

The time-stability of the electrical characteristics of chalcogenide materials is one of the most important issues for their use in nonvolatile solid state memory applications. In particular the electrical conduction of the glassy phase evolves with time due to two different physical phenomena: the crystallization and the so-called low conductivity drift. Despite the physics of crystallization having been extensively studied in literature, the latter is mainly described by phenomenological relationships, and its physical comprehension is still under discussion. In this paper we study the amorphous phase low-field conductivity drift and its dependence on the temperature experienced by the device. We developed an experimental procedure able to separate the reversible change in the electrical conductivity with temperature due to the material semiconductorlike behavior from the nonreversible one related to the drift mechanism. A drift model explaining such nonreversible conductivity change as a band diagram modification is also provided and calibrated on experimental data. The present work finally introduces alternative metrics for drift quantification that can be useful in order to compare different materials. [ABSTRACT FROM AUTHOR]

The time-stability of the electrical characteristics of chalcogenide materials is one of the most important issues for their use in nonvolatile solid state memory applications. In particular the electrical conduction of the glassy phase evolves with time due to two different physical phenomena: the crystallization and the so-called low conductivity drift. Despite the physics of crystallization having been extensively studied in literature, the latter is mainly described by phenomenological relationships, and its physical comprehension is still under discussion. In this paper we study the amorphous phase low-field conductivity drift and its dependence on the temperature experienced by the device. We developed an experimental procedure able to separate the reversible change in the electrical conductivity with temperature due to the material semiconductorlike behavior from the nonreversible one related to the drift mechanism. A drift model explaining such nonreversible conductivity change as a band diagram modification is also provided and calibrated on experimental data. The present work finally introduces alternative metrics for drift quantification that can be useful in order to compare different materials. [ABSTRACT FROM AUTHOR]

A study on the amorphous glassy phase of [Ge.sub.2][Sb.sub.2][Te.sub.5] low-field conductivity drift and its dependence on the temperature experienced by the device is presented. The results provided a drift model to explain the conductivity change as a band diagram modification and introduced alternative metrics for drift quantification that could be applied to compare different materials.

Byline: B. Bozzini, M. Boniardi Some mechanical and tribological properties of electroless Ni-P/ diamond composite films are measured, modelled by the finite element method and discussed. Preparation methods are briefly sketched. Hardness, Young's modulus and Milman's plasticity parameter are evaluated by diamond pyramid indentation methods; sliding wear behaviour is tested with the pin-on-disk technique. The application of the correlations for indentation testing is treated statistically in view of a quantitative use. The variations of mechanical properties induced by the dispersion of ceramic particles are quantitatively correlated with structural characteristics of the composite films.

Byline: M. Boniardi, G.C. Martinelli, B. Bozzini, R. Vitali The thermo-mechanical behaviour of supported MMC Ni-P(B4C) coatings was studied with a FEM modelling and experimental methods. Crystallisation residual stresses in the Ni-P matrix were computed by means of a sub-model technique and were measured with two independent methods X-ray diffractometry and Vickers indentation. The main conclusions of the FEM simulation are: (i) the matrix is in a tensile stress status and the dispersoid in a compressive one; (ii) the matrix is plasticised; (iii) no appreciable stress gradients as a function of coatings depth are pre- sent, except for slight (~5%) variations at the coating surface and at the coating-substrate interface. Experimental residual stresses are consistent and in quantitative agreement with maximum tensile stress values from FEM simulations. The stress distribution predicted by FEM was verified with crack path observations by SEM.

This work aims at presenting the use of new technologies in the field of forensic engineering. In particular, the use of UAV photogrammetry and laser scanning is compared with the traditional methods of surveying an accident site. In this framework, surveys must be carried out promptly, executed in a short time and performed so that the greatest possible amount of information is collected with sufficient accuracy to avoid the possibility of neglecting details once that the scene is no longer preserved. The combination of modern surveying techniques such UAV photogrammetry and laser scanning can properly fulfill these requirements. An experimental test has been arranged and instruments, procedures, settings, practical limits and results have been evaluated and compared with respect to the usual way of performing the survey for forensic purposes. In particular, both qualitative and quantitative considerations are given, assessing the completeness of the reconstructed model, the statistical evaluation of the errors and the accuracy achieved. [ABSTRACT FROM AUTHOR]

Introduction Certain surgical interventions, especially those involving upper GI tract remain challenging, due to high morbidity and mortality rates. The study of frailty in the surgical population has allowed the identification of those patients with a higher risk of poor postoperative outcomes. There remains a lack of evidence regarding the possibility of improving these results through a preoperative holistic management of the patients. The aim of this study is to evaluate whether preoperative treatment, in carefully selected patients, can improve the outcome following surgery. Patients and methods Between March 2015 and February 2016 patients affected by malignant tumors of the upper GI tract were enrolled at our Institution for major oncologic surgery. Amongst them, frail patients (Group 1) were identified using a validated scoring system and underwent a multidisciplinary preoperative management plan, composed of nutritional intervention, physical/respiratory enhancement and optimization of ongoing therapy. Short-term postoperative outcomes were then compared with a control group (Group 2) of patients with comparable frailty features and surgical indications, who had undergone surgery in the period from March 2013 to February 2014. Results 30-days and 3-months mortality, overall and severe complication rates were found to be significantly lower (p < 0.05) in Group 1 (41 patients) when compared with Group 2 (35 patents). No significant differences were recorded for the following outcomes: length of stay, referral to post-discharge institutionalisation and hospital re-admission. Discussion This study confirms advantages provided by preoperative treatment in frail patients, suggesting a new pathway for the improvement of postoperative outcomes. [ABSTRACT FROM AUTHOR]

In this paper the electrodeposition of DLC films on carbon steel from aqueous acetic acid solutions and their structural and mechanical characterization are reported. The process is performed at room temperature at relatively low cell voltages (from −8 to −20 V) with entirely environmentally friendly chemicals. Qualitative and quantitative evaluation of C hybridisation type have been performed by Raman spectroscopy. Microhardness and adhesion of the supported electrodeposited films have been measured by micro-indentation and scratch-testing. Notably, ductile failure was found to correspondence to a wide range of film growth conditions. The corrosion resistance of DLC-coated steel has been assessed by electrochemical impedance spectrometry in a neutral chloride solution. Optimal electrodeposition conditions were identified for the formation of high-quality DLC films ca. 270 nm thick with a high content of diamond-coordinated carbon and an ideal combination of hardness and adhesion; films formed under these conditions also confer some degree of corrosion protection to the steel substrate. [ABSTRACT FROM AUTHOR]

We report on the corrosion of austenitic (AISI304) and duplex (2205) stainless steels in H2O/KOH 50% at 120 °C. The research is based on a combination of electrochemical, structural and compositional analyses, aimed at assessing the surface modifications resulting from anodic attack and their impact on corrosion resistance. Linear sweep voltammetry and electrochemical impedance spectrometry measurements were carried out in an air-tight high-temperature cell. In-plane and cross-sectional SEM micrography, X-ray diffractometry and EDX profiling were used to characterise samples attacked under electrochemically controlled conditions. Electrochemical results have shown that AISI304 exhibits a complex passivating behaviour, while the anodic electrokinetics of the duplex is characterised by mixed kinetic control. AISI304 was found to fail by intergranular corrosion and to be covered: in passive conditions by acicular compounds and in transpassive conditions by a compact layer of corrosion products. Duplex samples, instead, exhibit an uniform form of corrosion morphology and bear a compact layer of corrosion products both in passive and in transpassive conditions. [ABSTRACT FROM AUTHOR]

The present paper focuses on the corrosion of an austenitic (AISI304) and a duplex (2205) stainless steel grade in molten KOH/NaOH 50 w/o eutectic at 250 °C. Experimental activities have been performed consisting in electrochemical measurements (linear sweep voltammetry and electrochemical impedance spectrometry) complemented by metallographic (in-plane and cross-sectional SEM micrography), structural (X-ray diffractometry) and compositional (EDX line-profiles) characterisation of the materials attacked under electrochemically controlled conditions. Electrochemical measurements have shown that AISI304 exhibits a passivating behaviour, characterised by two passivation peaks and a transpassive threshold, while duplex, does not yield a clear indication of passivation. AISI304 was found to fail by intergranular corrosion and to be covered in both passive and transpassive conditions, by an incoherent scale, containing electrolyte species. Duplex samples, instead tends to fail by homogeneous attack and exhibit a range of scale structures, depending on the applied potential. [ABSTRACT FROM AUTHOR]