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ABSTRACTLow-cycle fatigue life of Grade 300E and 500E reinforcing bars including the effect of buckling is evaluated. Low-cycle fatigue tests are carried out on un-machined specimens subjected to constant axial [...]

This work is focused on the study of the columnar-to-equiaxed transition in free graphite cast irons and the correlation of this phenomena with the temperature gradients during solidification. Samples of lamellar, compacted and spheroidal graphite irons were cast and their solidification macrostructures were revealed by application of the direct austempering after solidification technique. All the samples presented a sharp columnar-to-equiaxed transition and the determination of its location was carried out by visually inspecting each of the macrostructures obtained. In addition, computational simulations of filling and solidification of the castings were carried out to calculate the temperature gradient profiles along the whole volume of the casting samples. The comparison of experimental and numerical results showed that there is a critical temperature gradient value defining the columnar-to-equiaxed transition for all the free graphite cast irons samples analyzed in this work, regardless of their graphite morphology and casting geometry.

Considering that the current water crisis is largely a governance crisis, improving water governance will help to address current and future water challenges. Water governance is defined as the range of political, institutional and administrative rules, practices and processes through which decisions are taken and implemented, stakeholders can articulate their interests and have their concerns considered, and decision makers are held accountable for water management. The Water Governance Principles proposed by the Organisation for Economic Co-operation and Development (OECD) contribute to the creation of tangible public policies oriented toward effectiveness, efficiency, reliability and participation. The aim of this research is to apply the OECD Water Governance Indicator Framework at a local level and to identify gaps and challenges for water governance in the General Pueyrredon Municipality (GPM), Buenos Aires Province (BAP), Argentina. This framework was used as a diagnostic tool to assess water governance policy frameworks (what), institutions (who) and instruments (how). In general terms, there is a robust legal framework, there are enforcement institutions regarding water management and there is a good connection with them. However, the main challenges identified were in the 'how', since most of the instruments are partly or not implemented. [ABSTRACT FROM AUTHOR]

The Università Cattolica has long offered training courses for high school students as part of the PCTOs (Percorsi per le Competenze Trasversali e l'Orientamento), which take place in the form of seminars at the Milan campus. The CREA research centre has been entrusted with an art proposal that has touched upon different topics over the years. A common feature of the seminars is the experimentation of how art is a catalyst of energy for young students, enabling them, under the guidance of the experts, to realise tools for mediating the artistic heritage to their peers, using co-communication tools congenial to them, such as social media. [ABSTRACT FROM AUTHOR]

The development of a horizontal and a vertical mold designed to produce thin ductile iron plates is described. The aim of the design is to produce sound ductile iron plates that are large enough to create tensile test samples. An optimized design was also developed through the use of mathematical modeling.

Study design: Multicentre cross-sectional study. Objective: The objective of this study is to evaluate prevalence, location and characteristics of pain in hospital inpatients people with spinal cord injury (SCI). Setting: Ten Italian rehabilitation centres specialized in spinal injury care, where inpatients are admitted both after the acute lesion and for late complications (time since injury, median [IQR]: 0.8 [0.2–8.2] years). Methods: All the persons were submitted to AIS scale assessment [1] and modified Ashworth scale [2]; personal data and anamnesis were recorded; any pain within 1 week was investigated and the International Spinal Cord Injury Pain Basic Data Set (ISCIPBDS) Italian version [3] was administered by physicians expert in type of pain definition. Results: Of 385 included persons, 275 (72%) suffered pain, with the score value median [IQR]: 6 [4–8]. The worst pain of the person was nociceptive in 52% and neuropathic in 48% of the cases; 46% of nociceptive pain was located in the neck–shoulder region, whereas 67% of neuropathic pain was located in the sublesional part of the body. In 48% of the whole population, spasticity was observed but only 74% of them had pain. Being old and female are associated with high pain development, OR (95% CI): 1.24 (1.01–1.04) and 1.83 (1.05–3.20), respectively. Conclusions: A high prevalence of pain is confirmed in persons with SCI, with both nociceptive and neuropathic pain characteristics. Only old age and female sex resulted as variables highly associated with pain.

This work focuses on the study of the influence of microshrinkage cavities on the plastic deformation and fracture of ferritic ductile iron. Cast samples were especially developed to include dispersed microshrinkage. Tensile testing and digital image correlation analysis are employed to assess the influence of dispersed microshrinkage cavities as preferential sites for crack initiation and propagation under uniaxial static load. The results show that small microshrinkage cavities of up to 3.5 times the area of graphite nodules are not linked to the initiation and propagation of cracks in ductile iron. The methodology developed in this work becomes useful to evaluate the influence of size, distribution, and morphology of different microshrinkage defects on the damage evolution during tensile loading.

Three medium-carbon, high-silicon cast steels with different alloy contents were austempered at 330 °C for different holding times in order to obtain carbide-free bainitic microstructures. Aiming at evaluating the influence of holding time and microstructural features on strength and ductility, tensile properties were measured for each steel at selected austempering times. The results obtained indicate that it is possible to adjust holding time in order to obtain the best strength/ductility combination at determined austempering temperature. Moreover, it has been shown that the mechanical stability of retained austenite is the key factor in controlling tensile performance. Short austempering times result in low carbon enrichment of the austenite (low stability) and promote higher ultimate tensile strength and lower ductility. For longer austempering times, steels present a slight decrease in ultimate tensile strength but a marked increase in ductility. This work shows that it is possible to obtain cast steels with ultimate tensile strength of 1682 MPa, yield strength of 1493 MPa and total elongation of 12.5% by means of bainitic reaction. This strength/ductility combination and others reported in this study are remarkable for cast steels.

The satisfactory structural behavior observed during large earthquakes and the high seismicity of the country has conditioned the Chilean society to expect immediate occupancy performance level for their buildings under these extreme events, although the seismic design code in Chile mandates only a scope of life safety performance level. Based on observational and statistical evidence from recent strong earthquakes in Chile, it is concluded that the observed seismic resilience of buildings is a consequence of limiting damage, considering that operational performance and life safety are different challenges that require different approaches; furthermore, to provide society with resilient and safe buildings, both challenges must be met simultaneously and not alternatively. The present article describes the concepts, strategies, and future challenges in the context of the Chilean practice, and the authors describe several lessons learned from the design of thousands of concrete buildings that have experienced earthquakes with a magnitude of 8.0 and higher with limited damage; these lessons have proven to be effective in ensuring resilient structural performance under extreme seismic events.

Over the years, the majority of the studies that addressed the study of the solidification of free graphite cast irons have focused primarily on explaining the influence of graphite morphology on the solidification mechanism, but instead, have dedicated much less attention to the influence of the metallic phase that grows together with graphite, which is the austenite. However, the combined use of the direct autempering after solidification technique and color etching makes it possible today to extend the study of the solidification of these materials by considering the growth of the austenite. The objective of the present study is to demonstrate how these two techniques can be exploited to understand the solidification macro and microstructure and the microshrinkage cavities formation in free graphite cast irons.

This manuscript summarizes recent investigation of the authors into the solidification and shrinkage defect formation of ductile and compacted graphite cast irons. The study makes use of the DAAS (direct austempering after solidification) technique, developed earlier by some of the authors, to reveal the solidification grains. In addition, color metallography is used to reveal the microsegregation pattern. The formation of shrinkage defects is related to both the solidification macrostructure and the microsegregation pattern. The examination of the macrostructure shows that large solidification grains, composed by dendritic austenite and graphite, characterize the solidification of compacted graphite irons of carbon equivalent values ranging from hypoeutectic to hypereutectic. Similar results are observed for ductile iron, but in this case, the hypereutectic irons display a finer macrostructure. The characteristics of the primary austenite dendrites are revealed by the microsegregation pattern, which is exposed by the color etching reagent. This pattern also clarifies the nature of the interaction between the growing austenite and the compact and spheroidal graphite particles. The microshrinkage cavities in both ductile and compacted graphite irons form at the interior of the austenite grains, where fluid feeding cannot compensate the contraction of the last-to-freeze portions of the melt. Schematics of the solidification of ductile and compacted irons are proposed, accounting for the experimental observations.

There is a current discussion concerning the austenite grains of lamellar graphite irons and its growth at different carbon equivalent contents. The term “grain” is often employed to refer not only to the primary austenite, but also to the colonies or cells formed during the eutectic solidification. This investigation applies advanced experimental methods to study the solidification of lamellar graphite iron. A better understanding of the solidification process should lead to the design of better casting procedures. Samples of lamellar graphite iron were cast and directly austempered after solidification in order to reveal their solidification macrostructure. A typical ingot structure was found, with a narrow columnar-to-equiaxed transition. Electron backscatter diffraction technique was applied to confirm these macroscopic observations. Color etching was employed to determine the size of eutectic colonies at the columnar and equiaxed regions. The EBSD results confirm previous proposals, revealing that the solidification grains result from the growth of austenite dendrites. These grains include several eutectic colonies or cells inside, all these colonies or cells having the same crystalline orientation as the primary austenite dendrite. An analysis of the critical gradient for columnar-to-equiaxed transition could be developed. The size of the eutectic colonies at the columnar zone was found to be smaller than the size of the eutectic colonies at the equiaxed zone. Besides, the size of equiaxed grains strongly decreased with the increase in cooling rate, while no evident differences were obtained when the size of the columnar grains was measured.

ABSTRACTA high silicon cast steel was studied in the as-cast condition in order to characterise its solidification macrostructure and microsegregation. The steel, poured into 32 mm-keel-block-shaped moulds, has a coarse solidification structure and marked microsegregation, containing low-alloyed areas with a total alloy content (Cr + Mn + Si) of 2.3 wt-% and high-alloyed zones of 5.3 wt-%. The bainitic transformation behaviour at 300°C was studied at different austempering times. The bainitic reaction occurs at different rates within the specimen volume, because of its chemical heterogeneity. An austempering heat treatment leads to an inhomogeneous carbide-free bainitic microstructure with different phase amounts, morphologies and sizes. The heterogeneous distribution of sizes and chemical compositions of retained austenite is speculated to benefit mechanical properties.

Papular mycosis fungoides (PMF) is a rare variant of mycosis fungoides (MF). The exact nosology and prognosis of PMF are still unclear. We retrospectively identified cases of PMF from the files of the Department of Dermatology of the Medical University of Graz, Austria, and checked the follow-up data. The patients comprised 13 men and 5 women (median age: 57.5 y; range 13 to 77 y). In 4 patients, an initial clinicopathologic diagnosis of atypical pityriasis lichenoides was made; these cases were subsequently reclassified as PMF due to the onset of conventional patches of MF during follow-up. Follow-up data of our cases showed that 2 patients died of disease progression 50 and 199 months after the first presentation, respectively. Two patients are alive with progressive disease after 215 and 300 months, respectively. Ten patients are alive with stable disease (median: 70 mo). Four patients were in complete remission at last follow-up visit (median: 215 mo; 2 of them died of unrelated causes). Our data confirm that PMF represents a clinicopathologic variant of early MF with prognosis similar to conventional presentations of the disease. Familiarity with PMF and distinction from other cutaneous papular lymphoid proliferations is necessary for a precise diagnosis and management of these patients.

This work investigates the size and morphology of the primary austenite grains present in lamellar graphite cast iron. Samples of lamellar graphite iron were cast and austempered during the post-solidification cooling stage in order to preserve part of the original austenite at room temperature. Electron backscatter diffraction technique was applied to reveal the regions of different crystalline orientation of the austenite. The eutectic colonies and the last-to-freeze areas were also examined by color etching of the same regions previously analyzed by electron backscatter diffraction. The results reveal that the solidification units of lamellar graphite iron are formed by austenite grains that include several eutectic colonies inside, all of which have the same crystalline orientation as the primary austenite grain. For all the samples studied, it can be confirmed that there are no eutectic colonies with a different crystalline orientation than that of the primary austenite dendrites.

Multicentric prospective psychometric study. To provide a translation of the International Spinal Cord Injury Pain Basic Data Set (ISCIPBDS) for Italian persons and to evaluate the interrater reliability of the translated version. Ten Italian rehabilitation centres specialized in spinal injury care. The initial translation was performed by two medical doctors who had an in-depth knowledge of spinal cord injury (SCI), and then a back translation (from Italian to English) was given to an accredited agency. Sixty-six participants with SCI (53 men, 13 women; mean ± SD age: 53.4 ± 16.0 years) were evaluated by means of the Italian version of the ISCIPBDS by two different examiners. Intraclass correlation coefficient (ICC) or Cohen’s Kappa (ĸ) was calculated to test the interrater agreement for the test−retest cases. All 66 participants had at least one pain problem and 34% of them had only one type of pain. A good interrater agreement was obtained in terms of number of pain (ICC = 0.781), type of pain (ĸ= 0.683), pain intensity (ICC = 0.798), correspondence of pain localization (ĸ= 0.750), and the value of the pain interference in day-to-day activities, overall mood and night’s sleep (ICC = 0.827, ICC = 0.861 and ICC = 0.724, respectively). Eventually a prominent prevalence of neuropathic pain was recorded (64% from the first examiner and 62% from the second one). The authors propose the Italian version of ISCIPBDS that can be used for research and clinical evaluation of pain in SCI persons; it shows a significant interrater reliability.

The austemperability of seven high silicon cast steels with different alloy contents was characteri sed. The maximum round bar diameter that can be fully austempered changed from about 10?mm for an unalloyed steel to more than 70?mm for a low-alloy steel. The austemperability was calculated by applying a procedure based on a standard Jominy test and the characterisation of the microstructure along the Jominy sample. The method, which was validated experimentally, creates a relatively simple procedure to measure austemperability. Processing factors such as the ability of the salt bath to extract heat and the austempering temperature are accounted for the method. The metallographic study revealed the influence of microsegregation on hardenability, which is particularly important for cast steels.

This work studies the evolution of the macrostructure of gray cast iron as the carbon equivalent (CE) increases from near-eutectic to highly hypereutectic values. The macrostructure of spherical samples of flake graphite irons of CE ranging between 4.24% and 5.23% was revealed by using direct austempering after solidification technique (DAAS). The results were analysed by applying the concept of coupled zone for gray cast irons. The coupled zone is a region in the stable Fe-C-Si diagram in which solidification proceeds as a cooperative growth of both austenite and flake graphite. The coupled zone for gray cast iron is claimed to be asymmetrical as the eutectic reaction is extended towards the prolongation of the austenite liquidus line. All the samples investigated in the present study show the presence of relatively large austenite grains, demonstrating that the number of active nucleation sites of austenite per unit volume is small. The observation of the microstructure shows the presence of several units of coupled growth inside each austenite grain, what proves that many eutectic colonies have grown from the same austenite nucleus, even for highly hypereutectic compositions. Colour etching was employed to reveal the “hidden” dendrites present in the microstructure. The results suggest that proeutectic graphite is not a good nucleating agent for austenite. These results contribute to the understanding of the solidification of hypereutectic gray irons and verify the earlier understanding of the solidification of eutectic gray irons and its extension to hypereutectic compositions.

Ferritic ductile cast iron (FDI) microstructure is composed by graphite nodules embedded in a ferritic matrix. It is usual to assume that the ferritic matrix is homogeneous. However, the experimental analysis shows impurities and in some cases a high degree of heterogeneity. It is necessary to investigate the influence of these heterogeneities on the mechanical properties of FDI.This work focusses on the characterization of the elastoplastic properties of different zones of the ferritic matrix of FDI and the identification of the sequence and extent of the damage mechanisms at the micro-scale under uniaxial tensile loading.The methodologies for the characterization of the material micro constituents and micro-segregated zones involve nano-indentation and atomic force microscopy techniques in combination with computational modelling. The analysis is performed by applying inverse analysis algorithms proposed in the literature. The microsegregated zones are identified by using color etching. The assessment of the micro-scale damage mechanisms was performed by in-situ optical microscopy observation of tensile tests of very small specimens.The results led to the quantification of the differences in mechanical properties along the metallic matrix as a result of the existing heterogeneities and allow for a better understanding of the ductile iron damage mechanism.

Emergency medicine practitioners treat bleeding patients on a regular basis. Disorders of hemostasis are an additional challenge in these patients but can be assessed and managed in a systematic fashion. Of particular importance to the emergency clinician are the iatrogenic causes of abnormal hemostasis. Other acquired causes of abnormal hemostasis include renal disease, immune thrombocytopenia, thrombotic thrombocytopenic purpura, hemolytic uremic syndrome, acquired coagulation factor inhibitors, acute traumatic coagulopathy, liver disease, and disseminated intravascular coagulopathy.

PURPOSE: In presence of malignant melanoma lung metastases it is very difficult to define which is the therapy of choice. The role of surgery in a multimodality treatment is nowadays [...]

The multigroup transport theory is the basis for many neutronics modules. A significant point of the cross-section (XS) generation procedure is the choice of the energy groups' boundaries in the XS libraries, which must be carefully selected as an unsuitable energy meshing can easily lead to inaccurate results. This decision can require considerable effort and is particularly difficult for the common user, especially if not well-versed in reactor physics. This work investigates a genetic algorithm-based tool which selects an appropriate XS energy structure (ES) specific for the considered problem, to be used for the condensation of a fine multigroup library. The procedure is accelerated by results storage and fitness calculation speed-up and can be easily parallelized. The extension is applied to the coupled code SIMMER and tested on the European Sustainable Nuclear Industrial Initiative (ESNII+) Advanced Sodium Technological Reactor for Industrial Demonstration (ASTRID)-like reactor system with different fitness functions. The results show that, when the libraries are condensed based on the ESs suggested by the algorithm, the code actually returns the correct multiplication factor, in both reference and voided conditions. The computational effort reduction obtained by using the condensed library rather than the fine one is assessed and is much higher than the time required for the ES search.

Cutaneous mucinoses are a complex and diverse group of connective tissue disorders characterized by the accumulation of mucin and/or glycosaminoglycan in the skin and adnexa. Cutaneous focal mucinosis appears as a solitary, asymptomatic, skin-colored to white papule, nodule, or plaque located anywhere on the body or in the oral cavity. It presents mainly in adults and is characterized on histopathology by mucin throughout the upper and mid dermis. We describe the dermoscopy of two cases of cutaneous focal mucinosis. Both lesions presented a nonspecific homogenous whitish pattern; the first case also exhibited a sharply demarcated yellow border.