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Alloy 925 is a nickel-based superalloy usually produced by Electric Arc Furnace (EAF), followed by Argon Oxygen Decarburization (AOD) and Vacuum Arc Remelting (VAR). It can undergo to one VAR remelting (EAF-AOD-VAR) or, if necessary due to process instabilities, two VAR remelting (EAF-AOD-VAR-VAR). The characterization of A925 ingots remelted one or two times after forging and aging was carried out to enhance differences. The VAR remelting rate of single- or double-remelted samples was correlated to metallurgical and mechanical properties. The microstructure observation revealed a higher quantity of MC, M23C6 and TiN precipitates (both inter- and intragranular) in single-remelted samples: the intergranular ones increase in quantity going from the ingot center position to the external one where cluster of titanium nitrides were detected. The higher presence of intergranular precipitates causes a high deterioration of impact toughness (71.1 ± 12.7 vs 90.5 ± 7.1 J) and lateral expansion (0.91 ± 0.18 vs 1.14 ± 0.07 mm). On the other hand, the number of remelting does not affect other tensile properties and hardness. Therefore, the different behavior of forged ingots at single and double remelting are not related to the number of remelting and remelting rate. On the other hand, the slightly lower toughness of single-remelted forged ingots can be corelated to defects derived from casting. [ABSTRACT FROM AUTHOR]

The MiniMental Parkinson (MMP) has been derived from the MiniMental State Examination (MMSE) for the screening of cognitive impairment in Parkinson's disease by adding subtests that were focused on executive and visuo-spatial impairment more than on memory or language deficits. In this multicenter study, the psychometric and validity properties of the MMP have been evaluated in 69 cognitively intact and 52 cognitively impaired patients with Parkinson's disease, classified according to their performance at the Dementia Rating Scale. The MMP showed better metrics and convergent validity, and higher screening ability. However, its performance was not fully satisfying in terms of data distribution, coefficient of variation and specificity, and Receiver Operating Characteristic curves did not show clear cut superiority of either scale at their best sensitivity-specificity trade off. The MMP seems to be slightly preferable to the MMSE only at a cut off that favours sensitivity with respect to specificity, for screening purposes. The test is simple and quick, but has limitations in terms of validity. [ABSTRACT FROM AUTHOR]

The use of duplex stainless steel represents one possible efficient alternative of austenitic grade and an interesting resources for its high performance against stress corrosion cracking. Unfortunately such material shows some limitations in their use: for instance the sheets or plates of duplex stainless steels present anomalous and poor formability for plastic deformation processes. Such problems are mainly related to an unsuitable normal anisotropy coefficient, which might cause the 'necking' and 'earing' phenomena, especially during hot rolling. The study deals with the comparison of symmetric and asymmetric rolling technique on stainless steel duplex 2205 specimens. All the experiments were carried out using a laboratory mill, properly equipped with an individual engine for each rolling cylinder. The experimental parameters considered include three different pre-heating temperatures and two asymmetry ratios, while the reduction level is maintained constant for both rolling configurations. Moreover, the study involves also the analysis of the influence of solubilization quenching and the SEM, SEM-EBSD investigation dedicated to establish the microstructure modifications. The specimens were also studied through tensile tests to determine the influence of the rolling techniques on the mechanical properties of the product, focusing on the definition of the average anisotropy coefficient. The results of the experimental trials allow to conclude that the use of asymmetric rolling process induces an improved formability and increases duplex 2205 tensile properties. [ABSTRACT FROM AUTHOR]

PurposeTo study visual and anatomical outcomes of sequenced combined therapy using intravitreal bevacizumab followed by photodynamic therapy (PDT) in eyes with retinal angiomatous proliferation (RAP). Safety and rate of intravitreal injections were also evaluated.MethodsWe conducted a prospective non-comparative pilot study of consecutive patients newly diagnosed with RAP. PDT guided by indocyanine green (ICG) angiography was applied 8±2 days after the intravitreal bevacizumab (1.25 mg) injection. At baseline and every month after the injection, best-corrected visual acuity (BCVA) measurement, complete eye examination including dynamic fluorescein and ICG angiography, and optical coherence tomography (OCT) were performed.ResultsIn all, 21 eyes of 18 patients with RAP were enrolled. The mean age was 77 (range 65–86) years. Mean visual acuity at baseline was 0.63±0.25 logMAR. After treatment BCVA showed no statistically significant differences between each visit (P=0.10, ANOVA). At 9 months, the BCVA improved by three or more lines in three eyes (14%), remained stable in twelve eyes (57%), and worsened in six eyes (29%). Foveal thickness decreased significantly between baseline and all the follow-up visits (P<0.01, ANOVA). A total of 36 intravitreal injections were given during the study with a mean of 1.7 injections per eye (range 1–3 injections per eye). No ocular or systemic adverse events were reported.ConclusionA possible synergistic effect may arise from the combination of intravitreal bevacizumab with PDT for the treatment of RAP. These findings also suggest a possible benefit of combo therapy in the rate of intravitreal re-injections. [ABSTRACT FROM AUTHOR]

Foams and other highly porous materials with a cellular structure are known to have many interesting combinations of physical and mechanical properties. In addition, foaming of shape memory alloys (SMA) greatly improves the set of application possibilities. In this work an open-cell metal foam of a CuZnAl SMA is presented. This foam was produced through a recently proposed process, which consists mainly in molten metal infiltration of a bed of silica-gel particles and the subsequent use of hydrofluoric acid (HF) as solvent. The results showed that very regular open-cell foams could be obtained, having an almost spherical cell morphology and relative densities of approximately 0.3. Microstructural and compositional analyses on foamed specimens showed uniform microstructure of ligaments and the absence of SiO2 interaction with the metal. In this way the possibility of foaming CuZnAl system through the proposed low-cost process was clearly demonstrated. [ABSTRACT FROM AUTHOR]

The aim of this study is focused on the mechanical and the microstructural characterization of two Ni-based cast alloys: Hastelloy UNS N06200 and Hastelloy UNS N06022. The analysis has been performed through the observation of different microstructures obtained as a function of different cooling rates performed by the use of test blocks. After solidification, the specimens produced by different cooling rates have been extracted, and UNS N06200 samples have undergone a solution treatment process, while UNS N06022 samples have undergone a solution treatment followed by an ageing process. The mechanical properties have been measured, and some significant and consistent relationships have been pointed out with the heat treatment and the obtained microstructures. [ABSTRACT FROM AUTHOR]