The Joining of Alumina to Hastelloy by a TiZrCuNi Filler Metal: Wettability and Interfacial Reactivity.

A systematic microstructural characterization of alumina joined to Hastelloy C22® by means of a commercial active TiZrCuNi alloy, named BTi-5, as a filler metal is reviewed and discussed. The contact angles of the liquid BTi-5 alloy measured at 900°C for the two materials to be joined are 12° and 47° for alumina and Hastelloy C22® after 5 min, respectively, thus demonstrating good wetting and adhesion at 900 °C with very little interfacial reactivity or interdiffusion. The thermomechanical stresses caused by the difference in the coefficient of thermal expansion (CTE) between the Hastelloy C22® superalloy (≈15.3 × 10-6 K-1) and its alumina counterpart (≈8 × 10-6 K-1) were the key issues that had to be resolved to avoid failure in this joint. In this work, a circular configuration of the Hastelloy C22®/alumina joint was specifically designed to produce a feedthrough for sodium-based liquid metal batteries operating at high temperatures (up to 600 °C). In this configuration, adhesion between the metal and ceramic components was enhanced after cooling by compressive forces created on the joined area due to the difference in CTE between the two materials.

Chitosan-Functionalized Recycled Polyethylene Terephthalate Nanofibrous Membrane for Sustainable On-Demand Oil-Water Separation.

The preservation of marine ecosystems is one of the most severe challenges at present. In particular, oil-water separation from oil spills and oily wastewater is important. For this reason, a low-cost, effective, and sustainable polymeric solution is in high demand. In this work, a controlled-wettability membrane for selective separation of oil-water mixtures and emulsions is developed. The nanofibrous membrane is prepared via a facile and cost-effective electrospinning technique using environmentally sustainable materials, such as recycled polyethylene terephthalate and chitosan. The effect of different concentrations of chitosan on the morphology, chemical composition, mechanical properties, wettability, and separation performance of the membrane is evaluated. The membranes exhibited underoil superhydrophobic and underwater superoleophobic behavior, which is essential to perform the selective separation. In fact, the designed filter has competitive antifouling properties (oil intrusion pressure > 45 kPa) and showed high heavy- and light-oil/water separation efficiencies (>95%) both for emulsions and immiscible mixtures.

BRAF mutations in multiple sebaceous hyperplasias of patients belonging to MYH-associated polyposis pedigrees.

The characteristics of sebaceous gland hyperplasia (SGH) consist of yellowish or skin-colored papules and nodules. Chronic sun exposure and immunosuppressed conditions are the main environmental risk factors, whereas chronological aging regulated by hormones and molecular changes are the intrinsic risk factors. We have evaluated the contribution of BRAF, K-Ras, and N-Ras mutations to the pathogenesis of SGHs in four patients belonging to three MYH-associated polyposis (MAP) pedigrees. MAP is an autosomal-recessive disease characterized by multiple colorectal adenomas and cancer. Immunohistochemistry of mismatch repair and APC proteins was performed. DNA isolated from blood lymphocytes and formalin-fixed or paraffin-embedded SGHs was PCR amplified and sequenced. In the SGH patients, we detected T1796A heterozygous substitution (V600E) in the BRAF gene. Compound biallelic germline MYH mutations (Y165C/G382D, R168H/379delC, and Y90X/delGGA464) were detected in the MAP patients. In contrast to the majority of melanocytic lesions, activating hotspot mutations in BRAF have not been involved so far in the pathogenesis of SGH. BRAF mutation is not a specific marker of melanocytic cancerogenesis, and it can also be involved in SGHs. In both melanocytic and non-melanocytic skin tumors, BRAF mutation is linked to early tumorigenesis events.

'In vitro' study of chemotherapeutic activity of sulphimidazole on some sensitive and metronidazole-resistant Trichomonas vaginalis strains.

Trichomonacidal treatment based on 5-nitroimidazoles is problematic both when Metronidazole, the drug of choice, is ineffective owing to the presence of resistant strains and when bacterial aerobic infections are present. Sulphimidazole (SIZ) possesses two distinct functional groups: one sulphonamide, the other 5-nitroimidazole. Since SIZ is active against aerobic and anaerobic bacteria, we set out to discover whether, in view of the presence of the 5-nitroimidazole group, it could also be effective against Trichomonas vaginalis. Twelve strains of T. vaginalis were cultured in Modified Thioglycate Medium in anaerobic conditions; subsequently, their growth was monitored in the presence of Metronidazole (MZ), SIZ, Sulphamethoxazole (SMX), Trimethoprim (TMP) and their associations. Eight strains proved to be sensitive to Metronidazole (minimum lethal concentration=0.5 microgml(-1)) and four to be resistant (minimum lethal concentration=40-60 microgml(-1)). SIZ was active against both the sensitive and the Metronidazole-resistant strains (minimum lethal concentrations=0.5-1 and 10 microgml(-1), respectively), thus showing that the chemotherapeutic activities of the two functional groups coexisting in SIZ remain unimpaired.