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Abstract The development of new luminescent materials for lighting applications or stress sensors, mechano-driven lighting devices is a crucial technological topic. Materials suitable for these applications should guarantee a high chemical stability, easiness and green sintering procedure and optimal optical properties. In this framework Calcium Zinc oxysulfide (CaZnOS) represents one of the most promising materials, for its near UV excitation with a broad visible emission, a long phosphorescence and a mechano-luminescence effect that still need to be explored. In this work we report the optical properties and the kinetics of radiative recombination upon intrinsic and extrinsic excitation of pure CaZnOS, assessing the vibrational properties by means of Raman spectroscopy, and corroborated by DFT calculations. The analysis of time resolved measurements at room and low temperature (up to 10 K) give new insight on the distribution and nature of the defects that generate the luminescence upon external stress as well the long phosphorescence. Herein, we also present a model of the intrinsic defects and on the energy transfer mechanism among levels in pure CaZnOS matrix, opening new perspectives also on doped materials and for the development of piezoluminescent devices. Highlights • The experimental Raman spectrum of CaZnOS is shown. • The vibrational modes are assigned through DFT calculations. • Time resolved measurements evidence the presence of 5 optical channels. • The emissions are related to the presence of intrinsic defects. • The energy transfer mechanism among defect sites is related to tunnel effect. [ABSTRACT FROM AUTHOR]

Thymic carcinoid tumours constitute less than 1% of all carcinoids, and differ markedly from true thymomas in natural history, morphology, prognosis and therapeutic options. New clinical and diagnostic modalities are described in two brothers with thymic carcinoid associated with multiple endocrine neoplasia syndrome. Octreotide scintigraphy proved useful for diagnosis and follow-up, and somatostatin receptor positivity may provide new prospects for treatment of non-resectable or recurrent tumour. [ABSTRACT FROM AUTHOR]

The management of 27 consecutive deep sternotomy wound infections is reviewed. In 22 cases the initial treatment was debridement, sternal refixation and dilute antibiotic irrigation via multiple irrigation-suction catheters. In the nine cases (41%) in which these measures failed, more extensive sternal and costal cartilage debridement and closure with a muscle flap were performed. Five cases were initially managed with major reconstructive surgery. For reconstruction, a bilateral pectoralis major myocutaneous flap was used alone in eight cases, while in six the flap was insufficient to obliterate the whole poststernectomy space, and was supplemented with rectus abdominis muscle. Early mediastinitis can be effectively treated with thorough wound debridement and mediastinal irrigation, but if there is a two-week delay from the initial sternotomy to manifestation of infection, radical debridement with muscle flap closure should be seriously considered. [ABSTRACT FROM AUTHOR]