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Innovation in materials and joining processes continues to play a key role in the evolution of the transport sector, in general, and in the aviation in particular. Important factors of innovation are the improvement in material and processes performances, coupled to the associated cost reduction. Titanium alloys, characterized by high mechanical properties and corrosion resistance, are particularly interesting for the aeronautical sector. Their joining, from metal sheets with equal or different thicknesses, is mainly carried out by using laser or arc welding techniques. With the laser process, a high amount of energy is applied in a very limited area for a veiy short time, resulting in a reduced heat affected zone. With the arc welding, a large amount of heat is applied in a larger area for a longer time, obtaining a more extended heat affected zone. The combination of the process with high energy density (laser) with the high energy contribute (MIG) has been shown to enhance the beneficial effects of both processes (key-hole, ability to bridge sheet gap) while limiting their drawbacks (high thermal gradient, low mechanical resistance). In this paper, the hybrid Laser-MIG welding of Ti-6Al-4V was investigated. The welded joints were obtained from with 3-mm thick sheets using the double fillet welded T-joint. The main factors of evaluation were the morphology of the weld bead and energetic considerations. [ABSTRACT FROM AUTHOR]

Aim: Objective of this study was to compare the skin-patch test with the clinical diagnosis of oral lichenoid contact reaction (OLCR) as indicators for amalgam replacement., Methods: Of 53 patients (38 female and 15 male; mean age 48.7) with oral lichen planus (OLP), 26 were identified as having OLCR, and clinically graded according to the proximity of their lesions with amalgam fillings: class I (weak association), class II (moderate association), and class III (strong association). All OLCR patients were skin-patch tested for both standard (Brazilian) and specific allergens (TROLAB, Germany). Patients were considered skin-patch positive only if they developed positive skin reactions for thimerosal and/or amalgam components. Amalgam replacement was indicated in all class II and III patients. For class-I patients, amalgam replacement was indicated only if they were skin-patch test positive. Readings for the skin-patch test were made at 48h and 96h., Results: Of the 26 patients with OLCR, two missed the follow-up and were excluded, leaving 24 cases. Of these, four were class-I, and all were negative for the skin-patch test. Twelve were class-II, of whom seven were skin-patch positive. Eight were class-III, of whom six were skin-patch positive. Following amalgam replacement in the 12 class-II patients, six showed improvement and six had complete resolution, while in the eight class-III patients, two showed improvement and six a complete resolution., Conclusion: Clinical diagnosis of OLCR lesions is a more reliable indicator for the question of amalgam replacement than is the skin-patch test.

CIS is a flat, high-grade, non-invasive microscopic urothelial carcinoma. It is considered a precursor of invasive bladder cancer. CIS is classified as primary, secondary or concurrent, when occurred as isolated CIS without cuncurrent papillary tumors, or detected during the follow-up of patients with a previous papillary tumor, or finally in the presence of bladder neoplasm. BCG is widely established as the treatment of choice for CIS with a success rate of approximately 70%. BCG reduces the risk of progression of CIS into invasive carcinoma in 30 to 50% of cases. Direct and prolonged contact between the urothelium and BCG is a prerequisite for successful therapy. Discovery of CIS in the prostatic or membranous urethra represents an ominous sign. CIS may be present only in the epithelial lining of the prostatic urethra or in the ducts, or in the worst case it may be found in the prostatic tissue stroma. Urethral involvement by CIS is at high risk of tumor progression and development of metastases due to reduced thickness of lamina propria and absence of muscolaris mucosa. 83 patients, enrolled from 1/1996 to 12/2005 at our urological department with CIS: primary (focal and multifocal) in 25, secondary in 7 and cuncurrent in 51 (associated with T1bG3 cancer in 37 cases), and urethral CIS in 5 and conservatively treated by TUR and intravescical instillations of BCG, 4 developed afterwords only invasive cancer of the urethra in the absence of bladder involvement. In 2 cases cancer arised from the prostatic fossa after TURP, in 1 from membranous urethra and in the last from prostatic ducts. Among the 4 patients, 3 were treated by cystoprostatourethrectomy and Platinum-based chemotherapy, 1 refused surgical treatment. Two patients died for disseminated disease. 1 patient is alive at 60-month's follow-up. In the last patient cancer relapsed at 36-month's follow-up. We conclude that prostatic/urethral involvement during follow-up after successful intravesical treatment with BCG in CIS represents a high risk of developing invasive and incontrolled cancer. A careful watch is recommended in these patients.

Recent studies have suggested that simvastatin may exert endothelial-protective and anti-ischemic effects via nitric oxide (NO) mechanisms. The aim of this study was to evaluate, in isolated working rat hearts, the effect of acute simvastatin administration on endothelial and inducible NO-synthase (eNOS and iNOS) mRNA and on myocytic apoptosis after ischemia-reperfusion. We used isolated working rat hearts submitted to 15 min global, no-flow, normothermic ischemia and 180 min reperfusion. To detect myocytic apoptosis we used DNA agarose gel electrophoresis and Tunel technique; eNOS and iNOS expression were evaluated by multiplex reverse transcriptase-polymerase chain reaction; glyceraldehyde-3-phosphate dehydrogenase (G3PDH) was used as standard. The eNOS and iNOS mRNAs were expressed as G3PDH/eNOS and G3PDH/iNOS densitometric ratio (BioRad Gel Doc 1000). Hearts were divided into four groups: A) hearts excised and used as histological controls; B) untreated hearts submitted to ischemia and reperfusion; C) actinomicin D-treated (1.5 mg/kg) hearts, perfused with 25 microM simvastatin, subjected to ischemia and reperfusion; D) hearts treated with simvastatin 25 microM and submitted to ischemia and reperfusion. In Group B we evidenced a significant myocytic apoptotic damage, reduced in groups C and D. In Group B an increase in G3PDH/eNOS ratio vs Group A was detected; in Group D a reduction in G3PDH/eNOS ratio vs Group B occurred; no significant changes were observed between groups C and D. As for G3PDH/iNOS ratio, it was significantly increased in Group D with respect to groups A and B. Our data suggest that simvastatin in acute may modulate NO-synthase mRNA expression (induction of eNOS mRNA by means of post-transcriptional mechanisms and inhibition of iNOS postischemic overexpression) and reduce myocytic apoptosis.