Microstructural and Mechanical Properties of Al2O3 and Al2O3/TiB2 Ceramics Consolidated by Plasma Pressure Compaction

Alumina oxide ceramics were produced by plasma pressure compaction (P2C) sintering process. Two types of pure α-alumina (Al2O3) and a mixture of alumina and titanium diboride (TiB2) powders were used as starting materials. Microstructure and mechanical properties, namely hardness, elastic modulus, and fracture toughness, were analyzed and correlated to the type of the sintered powders and the adopted manufacturing route. The microstructural development and the chemical composition variation induced by the sintering process were assessed by using scanning electron microscopy and x-ray diffraction. Nano-indentation and Chevron notch beam techniques were adopted to estimate the mechanical properties of the sintered ceramics. The conducted analyses show the capability of P2C technique to produce sound alumina ceramics. Pure alumina bulks exhibit a good level of compaction and mechanical properties close to those achievable with conventional sintering processes, such as hot isostatic pressing or spark plasma sintering. No significant alterations in the chemical composition of the ceramics were observed. The addition of the titanium diboride in the alumina powders caused a moderate increase in the grain size lowering the hardness and Young’s modulus of the sintered alumina and, at the same time, increased its fracture toughness to the occurrence of toughening mechanisms, like crack bridging and crack deflection

Primary Cardiac Angiosarcoma: A Fatal Disease

A 42-year-old man with a cardiac tamponade underwent an urgent pericardiotomy that showed tumoral tissue, covering the surface of the right atrium. The tumor was then partially excised, and the histological examination revealed the presence of a moderately-differentiated angiosarcoma. The patient was then referred to the oncology unit and scheduled for a chemotherapy schedule including Epirubicin (60 mg/m2, on days 1 and 2) plus Ifosfamide (2000 mg/m2, on days 1 to 3) and Uromitexan (2000 mg/m2 at hours 0, 4, 8 after IFO). All drugs were administered every three weeks. After two cycles, a restaging work-up revealed a partial remission. The treatment was continued for another two cycles. A new evaluation by cardiac MRI evidenced a local and distant (lung) progression of disease. The patient died after three months. This paper confirms that cardiac angiosarcoma is a fatal disease, and the prognosis is usually 6–11 months from time of diagnosis

Effects of Ti6Al4V mechanical and thermal surface modification on the adhesion of a chitosan-bioactive glass coating

Biomedical implants interact with human tissues introducing significant perturbation into the body. Implant surfaces can be then functionalized enabling better biocompatibility. At the same time, the additional use of a coating provides further functions such as corrosion protection, osteointegration, and drug delivery. In this context, a composite made of chitosan and bioactive glass nanoparticles has been used for coating Ti6Al4V alloy samples processed beforehand using different processes, i.e., polishing, milling, grit blasting, and electrical discharge machining. Experiments have been carried out to correlate substrate surface conditions and coating effectiveness in terms of scratch resistance with the final aim to obtain suitable guidelines to improve substrate-coating performances

Early stage sinkhole formation in the acque albule basin of central Italy from geophysical and geochemical observations

Sinkhole occurrence along the Tyrrhenian margin of the Central Apennines is of great importance for applied research, land management and civil protection. This study reports on GPS-altimetry magnetic, gravity, geoelectric, seismic, and soil gas measurements of a rapidly developing sinkhole near the Guidonia military airport. The measurements revealed an elliptical 2-m depression elongated 220 m in the NNE-SSW direction with the minor axis of 110 m. In spring of 2013, two vertical cavities formed in the eastern and northeastern flanks of the depression whose depths and shapes are rapidly evolving with the formation of widespread fracturing along the same side. The geophysical observations image the developing sinkhole to a depth of some 50 m, the presence of the Travertino lithotype around the depression (down to at least 40 m), and the lack of this lithotype below the lowered area. The sinkhole's evolution appears to be structurally controlled by local and regional faulting. These results are useful for designing further geophysical, geotechnical and geochemical studies to monitor the sinkhole's evolution and to assess the hazard it presents in densely urbanized area.Published36-477A. Geofisica di esplorazioneJCR Journalreserve

Type 2 diabetes, depressive symptoms and trajectories of cognitive decline in a national sample of community-dwellers: a prospective cohort study

We examined the individual and synergistic effects of type 2 diabetes and elevated depressive symptoms on memory and executive function trajectories over 10 and eight years of follow-up, respectively. Our sample comprised 10,524 community-dwellers aged ≥50 years in 2002±03 from the English Longitudinal Study of Ageing. With respect to memory (word recall), participants with either diabetes or elevated depressive symptoms recalled significantly fewer words compared with those free of these conditions (reference category), but more words compared with those with both conditions. There was a significant acceleration in the rate of memory decline in participants aged ≤50±64 years with both conditions (-0.27, 95% CI, -0.45 to -0.08, per study wave), which was not observed in those with either condition or aged ≥65 years. With respect to executive function (animal naming), participants aged 65 years with diabetes or those with elevated depressive symptoms named significantly fewer animals compared with the reference category, while those with both conditions named fewer animals compared with any other category. The rate of executive function decline was significantly greater in participants with both conditions (-0.54, 95% CI, -0.99 to -0.10; and ±0.71, 95% CI, -1.16 to -0.27, per study wave, for those aged 50±64 and ≥65 years, respectively), but not in participants with either condition. Diabetes and elevated depressive symptoms are inversely associated with memory and executive function, but, individually, do not accelerate cognitive decline. The co-occurrence of diabetes and elevated depressive symptoms significantly accelerates cognitive decline over time, especially among those aged 50±64 years

Oxaliplatin, 5-fluorouracil/leucovorin and epirubicin as first-line treatment in advanced gastric carcinoma: a phase II study

The association between oxaliplatin and 5-fluorouracil (5-FU) has been extensively reported to improve prognosis of gastric cancer patients. The present study is aimed at evaluating response rate and the toxicity profile of the association with oxaliplatin, 5-FU/lecovorin and epirubicin in gastric cancer patients with locally advanced or metastatic disease. Thirty-six patients have been enrolled and 35 evaluated. The treatment schedule was oxaliplatin (100 mg m−2), 5-FU (400 mg m−2), leucovorin (40 mg m−2) and epirubicin (60 mg m−2) intravenously. administered every 3 weeks for 6 months, for a total of 185 therapy cycles . Response rate and toxicity were assessed according to the international WHO criteria. Every patient received a mean of 5.3 therapy cycles in a day-hospital setting. Sixteen of 35 patients (46%) showed an objective response, two complete response and 14 partial response. Median time to progression was 33 weeks with an overall median survival of 49 weeks. During the study, anaemia grade 3 and neutropenia grade 3 were observed in 9 and 11% of patients respectively. A grade 3 periferic sensorial neuropathy was observed in 6% of patients. No life threatening or cardiac toxicity was recorded. The regimen used showed anticancer activity against gastric carcinoma, a tolerable toxicity profile and excellent patient compliance