Primary Ewing sarcoma of the coronoid process of mandible.

Ewing sarcoma (ES) is a rare, primary malignancy of the bone that occurs mainly in childhood and early adolescence. ES usually occurs in long bones of the axial skeleton. Although uncommon in the jaws, ES at this site is most likely to occur in the posterior mandible. The outcome for patients with localised disease has improved over the decades, due to better combination chemotherapies and better methods of local control. We present the clinicopathologic features and management of a case of ES that developed in the left coronoid process of the mandible of a 31-year-old male. Chemotherapy and, later, a segmental mandibulectomy were used to achieve local control. A fibula-free flap repair was performed with good aesthetic results. This case elucidates the importance of the interdisciplinary approach required for the evaluation and treatment of this aggressive neoplasm.

A 65-year old female with synchronous HIV and Extramedullary Plasmacytoma of Maxillary sinus.

Extramedullary plasmacytoma in the head and neck region is a rare malignant neoplasm comprising approximately 3% of all the plasma cell neoplasms and less than 1% of head and neck tumors. This extraskeletal lesion is a unifocal, monoclonal, neoplastic proliferation of plasma cells. Some investigators believe that this lesion represents the least aggressive part of the spectrum of plasma cell neoplasms which extends to multiple myeloma. Therefore, plasmacytoma is believed to have clinical importance. We report a case of extramedullary plasmacytoma in the right maxillary sinus of a 65-year-old HIV positive female as a clinical rarity with review of the relevant literature.

Study of self-generated magnetic fields in laser produced plasmas using a three-channel polaro-interferometer.

Self-generated magnetic fields produced in laser plasmas at moderate laser intensities have been measured using a three-channel polaro-interferometer. The main elements of this device are two birefringent calcite wedges placed between two crossed polarizers. Using this device, the spatial profiles of (a) the rotation angle (polarometry), (b) the electron density (interferometry), and (c) the transmitted probe beam intensity (shadowgraphy) are recorded simultaneously using a digital camera with a large format CCD in a single laser shot. Magnetic fields of 2-4 MG had been estimated in aluminum plasma at laser intensities ~10(13) W/cm(2). It is also possible to use this device in other configurations to get time resolved information.

Characterization of X-ray contact microscopic imaging in keV spectral region using laser produced plasmas.

An experimental study is performed of soft X-ray emission from laser produced plasmas for single shot X-ray contact microscopic imaging of physical and biological microstructures. Planar copper targets are irradiated by 10 J, 28 nS Nd:glass laser pulses in the intensity range of 1011 W/cm2 to 3 × 1012 W/cm2. Measurements of keV X-ray emission viz. X-ray intensity scaling with laser intensity, X-ray source size, X-ray conversion efficiency and exposure dose on the sample are presented. Fine copper grids of 70 mm mesh size and 10 mm thickness are used as test samples for imaging on ERP-40 photoresist. A spatial resolution of ~195 nm is observed, consistent with theoretical estimate considering the contribution of geometrical and diffraction blurring, and statistical noise of photons incident on the sample. This study should be useful in proper selection of source parameters for optimization of spatial resolution in single shot keV contact imaging.