Phase stability in Duplex stainless steels

This thesis summarizes the work performed during the research activities developed in the three-years course of scientific training for the attainment of the Doctor of Philosophy degree. The research was mainly focused on the study of the physical metallurgy of Duplex stainless steels, a particular class of stainless steels having a biphasic austeno-ferritic microstructure, with the aim to characterize their microstructural stability as a consequence of heat treatments and cold plastic deformation. The choice of the research topic was dictated by the increasing use of these steels for industrial applications, being able to provide high-strength features and elevated performances against corrosive attacks, making them particularly suitable and competitive in aggressive environments, also as structural materials. However, there are limitations to the use of Duplex steels, owing to the occurrence of microstructural modifications, either during high-temperature exposures or as a result of cold working, which can compromise their interesting features. The thesis is organized into three main parts; the first chapter is focused on properties, problems and applications of Duplex stainless steels, providing a general introduction about these materials and in which particular emphasis was given to those metallurgical variables that affect the production process and the microstructural stability. In Chapter 2 and 3, the research activities concerning the effects of heat treatments (Chapter 2) and cold rolling (Chapter 3) the on the Duplex properties are presented and discussed. It was considered appropriate to report a brief summary of literature at the beginning of the second chapter, aimed to provide the reader with the “state of art” on the effects of thermal cycles on Duplex steels properties, whereas the remaining sections of the chapter are a constitutive part of the research activities. In addition, the experimental part discussed in Chapters 2 and 3 has been integrated with a section devoted to the study of Duplex application at an industrial scale (Appendix A), aimed to the employment of these materials in marine environment. Finally, Appendix B reports the results concerning archaeometallurgical studies, which has contributed to the scientific training of the candidate, even if it was not related to the main research topic. Experiments and training courses were mainly carried out in facilities and laboratories pertaining to the Industrial Engineering Department (DII ) of the University of Padua – and particularly those belonging to the DII “metallurgy group” – under the supervision of Prof. Irene Calliari and Prof . Emilio Ramous. However, certain specific activities have required the involvement of other structures external to the University of Padua; among these, the neutron diffraction measurements were carried out in the INES diffractometer, located at the ISIS facility in the Rutherford Appleton Laboratory (Didcot, UK), in collaboration with Dr. Antonella Scherillo and Dr. Francesco Grazzi (CNR of Florence), while the magnetic measurements were performed in the laboratories of the University of Budapest (BME), in collaboration with Prof. István Mészáros. Moreover, the EBSD analysis on the deformed materials were executed by Dr. Paola Bassani (CNR of Lecco), while the mechanical impact tests were carried out in collaboration with Dr. Cinzia Menapace (University of Trento), in the university laboratories, and with Eng. Marco Pizzo (Unilab Laboratori Industriali srl), in the Exova CTR srl laboratories. The results of the studies pertaining to the research period and reported in this thesis have contributed to enhance the knowledge about Duplex stainless steels, in relation to the effects that microstructural modifications can induce on the materials properties, and were of appropriate scientific relevance to allowing their presentation in international conferences and their publication in scientific journals

Large mammal remains from the early pleistocene site of Podere San Lorenzo (Perugia, Central Italy)

Most of the research on fossil mammals from Umbria (central Italy) has been carried out in the southwestern branch of the Tiber basin, due to its paleontological richness. This portion of the basin extends from Perugia to Terni and corresponds to a well-defined half-graben filled with fluvial-lacustrine deposits. The paleontological sample presented here was discovered in a sand and gravel quarry at Podere San Lorenzo, East of the town of Deruta. The stratigraphic succession exposed in the quarry is no longer visible, but we describe here a new outcrop (Palazzone), which is not far from Podere San Lorenzo and shows comparable facies associations. The two successions were deposited in a fluvial environment characterized by an average reduction of the hydrodynamic energy from the bottom upwards. They are referred to the Early Pleistocene Santa Maria di Ciciliano Subsyntheme (Madonna dei Bagni Lithofacies). Large mammal remains are attributed to Mammuthus cf. meridionalis (Nesti, 1825), Stephanorhinus etruscus (Falconer, 1859), Equus stenonis Cocchi, 1867, Leptobos cf. etruscus (Falconer, 1868), ‘Pseudodama’ nestii (Azzaroli, 1947), and Sus strozzii Forsyth Major, 1881. Some hyena coprolites are also reported. The assemblage is typical of the early Late Villafranchian Land Mammal Age and can be referred to the Olivola/Tasso Faunal Units (about 2.0–1.8 Ma). This is in agreement with the alleged age of some other assemblages found in the southwestern branch of the Tiber basin (e.g., Torre Picchio, Villa San Faustino, Colle Sant’Andrea, Pantalla)

La enseñanza de las matemáticas en un curso de formación en contexto de pandemia: la percepción de futuros profesores de matemáticas de Ecuador

Al mundo le ha tocado vivir una transformación forzada debido a la emergencia sanitaria provocada por el Covid-19, lo que ocasionó cambios bruscos en todos los ámbitos, en especial el educativo, en donde tanto docentes como estudiantes no han estado preparados para afrontarlo. Repentinamente las aulas se transformaron en espacios virtuales de aprendizaje improvisados, por lo que ante esta situación surgió la idea de investigar cual es la percepción de los futuros profesores de matemáticas, estudiantes de la carrera de Pedagogía de las Ciencias Experimentales: Matemáticas y Física de la Universidad de Cuenca, acerca de las clases virtuales realizadas en el periodo marzo-abril 2020 en las asignaturas de matemáticas de la carrera. Para ello se aplicó un cuestionario en línea con preguntas de opción múltiple, donde se concluye que, aunque los docentes de la carrera trabajen con algunas de las tendencias actuales de la enseñanza y aprendizaje de las matemáticas, varios de ellos llevan sus clases tradicionales a las pantallas, no existe mayor cambio de tipo metodológico o de estrategias de enseñanza aprendizaje y se visualiza una falta de capacitación tecnológica y del uso instrumental de herramientas que ayuden a esta nueva modalidad de aprendizaje. Además, se concluye que se deben mejorar las prácticas virtuales con nuevas metodologías que aporten a la interacción entre docentes y estudiantes

Vigna Nuova : the first Middle Villafranchian mammal assemblage from the Valdichiana Basin, Perugia (Italy)

The region of Umbria (Central Italy) represents one of the most interesting areas for the study of Mediterranean Plio-Pleistocene mammal faunas due to the occurrence of numerous paleontological deposits. Most of the fossils have been discovered within the Tiberino Basin, which extends across the centre of the territory for ca. 1800 km2, and the small Tavernelle-Pietrafitta Basin, south of Lake Trasimeno. Herein, we provide an additional report on an assemblage within continental deposits from the locality of Vigna Nuova (Piegaro, Perugia) in the Valdichiana Basin, which are observed to crop out in only a few areas of western Umbria. Taphonomic and geological evidence, coupled with rare excavation notes, have allowed the sample to be divided into two assemblages. The younger was collected from the conglomerates (here called "upper layer") which are still visible on the outcrop and is composed only of remains of cf. Leptobos. The data obtained from this fragmentary sample together with some sedimentological-stratigraphic considerations suggest that it can be correlated with other well-known Valdichiana assemblages (e.g., Selvella, Farneta), dated at ca. 1.5 Ma. The older sub-sample comes from a putative paleosol (here called "lower layer") no longer visible in the field. It includes cf. Megantereon, Canis sp., Mustelidae indet., Proboscidea indet., Equus cf. senezensis, cf. Leptobos, Croizetoceros ramosus, Pseudodama sp., Cervidae indet. (large size), and Sus cf. strozzii. This assemblage can be referred to the Coste San Giacomo Faunal Unit (late Middle Villafranchian; ca. 2.2-2.1 Ma). It represents the first wellpreserved sample of this age in Umbria and one of the few recorded in Italy, opening new interesting research perspectives on the distribution of mammals within the Peninsula and also on the stratigraphy and evolution of the Valdichiana Basin. "Aggiungeva che per scavare le poche ossa che mi avrebbe subito inviate aveva dovuto faticare enormemente e lottare per due giorni contro ogni sorta di difficoltà. Ricevuto il graditissimo invio mi affrettai a consolidare e restaurare con ogni cura quelle primizie ed oggi sono lieto di poter annunziare, in così solenne adunanza, la interessante scoperta…" ("He added that in order to excavate the few bones that he would immediately send me he had had to work enormously and struggle for two days against all sorts of difficulties. Having received the very welcome shipment, I hastened to consolidate and restore those fruits of the soil with every care and today I am pleased to be able to announce, in such a solemn meeting, the interesting discovery…"). Giovanni Capellini, 189

Geometry and stratigraphic relationships of lower Oligocene coral reefs in Lumignano (Berici Hills, northern Italy)

The Cliffs of Lumignano (Northern Italy) are a renowned climbing area, set on the steep walls of lower Oligocene limestones of the Castelgomberto formation which are made mainly of coral boundstone. Lumignano lies approximately on the south-eastern margin of a Cenozoic carbonate platform known as the Lessini Shelf, but the depositional environment of coral reefs is still debated, and it is unclear whether it was a Caribbean-type carbonate platform with a lagoon and steep slope, or a carbonate ramp with coral reefs on the mid ramp. We produced a geological map of the Lumignano area, in which five lithofacies are distinguished and mapped within the Castelgomberto formation. Their spatial distribution and main sedimentological characters outline that landward of coral reefs, a high-energy environment was present and was shallower than the reefs. Seaward of coral reefs, coralline algae and marlstones with bryozoans occur, while no evidence of a slope made of coral rubble was found. Hence, the detailed geological mapping and the documentation of the stratigraphic relationships between lithofacies provided a valuable contribution to the understanding of depositional environments of the lower Oligocene Lessini Shelf. This work also suggests elements for a better definition of the Castelgomberto formation, which could be split in members or lithofacies that can be mapped at a reasonably large scale (1:10000). The coralline algal lithofacies of the Castelgomberto formation is locally indistinguishable from the analogous facies of the underlying Priabona formation, but the boundary between these two units is always marked by an unconformity, which is easy to identify and may be used for the lithostratigraphic definition of the Castelgomberto formation

Diagnostic accuracy of clinical tests to rule out elbow fracture: a systematic review

Elbow traumas represent a relatively common condition in clinical practice. However, there is a lack of evidence regarding the most accurate tests for screening these potentially serious conditions and excluding elbow fractures. The purpose of this investigation was to analyze the literature concerning the diagnostic accuracy of clinical tests for the detection or exclusion of suspected elbow fractures. A systematic review was performed using the Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies (PRISMA-DTA) guidelines. Literature databases including PubMed, Cumulative Index to Nursing and Allied Health Literature, Diagnostic Test Accuracy, Cochrane Library the Web of Science, and ScienceDirect were searched for diagnostic accuracy studies of subjects with suspected traumatic elbow fracture investigating clinical tests compared to imaging reference tests. The risk of bias in each study was assessed independently by two reviewers using the Quality Assessment of Diagnostic Accuracy Studies 2 checklist. Twelve studies (4,485 patients) were included. Three different types of index tests were extracted. In adults, these tests were very sensitive, with values up to 98.6% (95% confidence interval [CI], 95.0%–99.8%). The specificity was very variable, ranging from 24.0% (95% CI, 19.0%–30.0%) to 69.4% (95% CI, 57.3%–79.5%). The applicability of these tests was very high, while overall studies showed a medium risk of bias. Elbow full range of motion test, elbow extension test, and elbow extension and point tenderness test appear to be useful in the presence of a negative test to exclude fracture in a majority of cases. The specificity of all tests, however, does not allow us to draw useful conclusions because there was a great variability of results obtained. Level of evidence IV

Predição Ab Initio da estrutura supersecundária de modelos atomísticos de um polipeptídeo : o alpha-helical hairpin

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Intraocular Pressure Changes After Intravitreal Fluocinolone Acetonide Implant: Results from Four European Countries

none14siIntroduction: The 0.19 mg fluocinolone acetonide (FAc) intravitreal implant delivers a continuous intravitreal corticosteroid dose for the treatment of refractory diabetic macular oedema (DMO). The aim of this study was to assess the impact of an FAc intravitreal implant on intraocular pressure (IOP). Methods: We retrospectively collected anonymised data on the patients’ characteristics, DMO treatment, and IOP and IOP-lowering treatments before and after the FAc intravitreal implant between September 2013 and March 2020 in several European centres. Results: A total of 221 eyes from 179 patients were included. The mean follow-up duration was 13.4 (± 12.5, range 2.4–33.5) months. Overall, 194 eyes (88.2%) had received an intravitreal dexamethasone injection before the FAc intravitreal implant. For 25 eyes (11.3%) there was a history of glaucoma, and 52 eyes (23.5%) had previous IOP-lowering treatment. Mean IOP before injection was 14.7 (3.4) mmHg and increased to 16.9 (3.7) mmHg 12 months after injection (P < 0.0001). During follow-up, 55 eyes (24.9%) required the addition or initiation of topical IOP-lowering medication, only one patient (0.5%) had laser trabeculoplasty and one patient (0.5%) a minimally invasive glaucoma surgery, and no patient required incisional IOP-lowering surgery. Conclusion: The FAc intravitreal implant led to substantial IOP elevation. This elevation was monitored most of the time with addition or initiation of topical IOP-lowering medication.openLebrize S.; Arnould L.; Bourredjem A.; Busch C.; Rehak M.; Massin P.; Barbosa-Breda J.; Lupidi M.; Mariotti C.; Hamza M.; Grise-Dulac A.; Gabrielle P.-H.; Baillif S.; Creuzot-Garcher C.Lebrize, S.; Arnould, L.; Bourredjem, A.; Busch, C.; Rehak, M.; Massin, P.; Barbosa-Breda, J.; Lupidi, M.; Mariotti, C.; Hamza, M.; Grise-Dulac, A.; Gabrielle, P. -H.; Baillif, S.; Creuzot-Garcher, C

Contemporary urologic minilaparoscopy : indications, techniques, and surgical outcomes in a multi-institutional European cohort

OBJECTIVES: To provide an analytical overview of contemporary indications, techniques, and outcomes of urologic minilaparoscopy (ML) in multiple European centers. METHODS: Data of patients who had undergone a minilaparoscopic urologic procedure at nine European institutions between 2009 and 2012 were retrospectively gathered. Surgical procedures were classified as upper or lower urinary tract and as ablative or extirpative and reconstructive. The main surgical outcome parameters were analyzed and relevant operative data related to the surgical technique were recorded. RESULTS: Overall, 192 patients (mean age 45.25±17.8 years) were included in the analysis. Most of them were nonobese (mean body mass index [BMI] 24.7±3.6?kg/m(2)) at low estimated surgical risk (mean American Society of Anesthesiologists [ASA] 1.69±0.68). Indications for surgery were mostly nononcologic (132 cases, 68.8%). Most of the procedures were done in the upper urinary tract (133 cases, 69.2%) and were mostly with a reconstructive intent (109 cases, 56.7%). Overall operative time was 132.7±52.3 minutes with an estimated blood loss of 60.9±47.6?mL while the mean hospital stay was 5±2.1 days. Most of the postoperative complications were low Clavien grade (1 and 2), with only one (0.5%) grade 3 and one (0.5%) grade 4 complications recorded. CONCLUSIONS: A broad range of common procedures can be safely and effectively performed with ML techniques. By duplicating the principles of standard laparoscopy, but potentially offering less surgical scar and trauma, ML can be regarded as a viable option when looking for a virtually "scarless" surgery

Prostate Cancer in Renal Transplant Recipients: Results from a Large Contemporary Cohort

Objectives: The aim of this study was to assess the natural history of prostate cancer (PCa) in renal transplant recipients (RTRs) and to clarify the controversy over whether RTRs have a higher risk of PCa and poorer outcomes than non-RTRs, due to factors such as immunosuppression. Patients and Methods: We performed a retrospective multicenter study of RTRs diagnosed with cM0 PCa between 2001 and 2019. Primary outcomes were overall (OS) and cancer-specific survival (CSS). Secondary outcomes included biochemical recurrence and/or progression after active surveillance (AS) and evaluation of variables possibly influencing PCa aggressiveness and outcomes. Management modalities included surgery, radiation, cryotherapy, HIFU, AS, and watchful waiting. Results: We included 166 men from nine institutions. Median age and eGFR at diagnosis were 67 (IQR 60–73) and 45.9 mL/min (IQR 31.5–63.4). ASA score was >2 in 58.4% of cases. Median time from transplant to PCa diagnosis was 117 months (IQR 48–191.5), and median PSA at diagnosis was 6.5 ng/mL (IQR 5.02–10). The biopsy Gleason score was ≥8 in 12.8%; 11.6% and 6.1% patients had suspicion of ≥cT3 > cT2 and cN+ disease. The most frequent management method was radical prostatectomy (65.6%), followed by radiation therapy (16.9%) and AS (10.2%). At a median follow-up of 60.5 months (IQR 31–106) 22.9% of men (n = 38) died, with only n = 4 (2.4%) deaths due to PCa. Local and systemic progression rates were 4.2% and 3.0%. On univariable analysis, no major influence of immunosuppression type was noted, with the exception of a protective effect of antiproliferative agents (HR 0.39, 95% CI 0.16–0.97, p = 0.04) associated with a decreased risk of biochemical recurrence (BCR) or progression after AS. Conclusion: PCa diagnosed in RTRs is mainly of low to intermediate risk and organ-confined at diagnosis, with good cancer control and low PCa death at intermediate follow-up. RTRs have a non-negligible risk of death from causes other than PCa. Aggressive upfront management of the majority of RTRs with PCa may, therefore, be avoided