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The combinations of a 60 fps kV x-ray flat panel imager, a 19 focal spot kV x-ray tube enabled by a steered electron beam, plus SART or SIRT sliding reconstruction via GPUs, allow real time 6 fps 3D-rendered digital tomosynthesis tracking of the respiratory motion of lung cancer lesions. The tube consists of a “U” shaped vacuum chamber with 19 tungsten anodes, spread uniformly over 3 sides of a 30 cm x 30 cm square, each attached to a cylindrical copper heat sink cooled by flowing water. The beam from an electron gun was steered and focused onto each of the 19 anodes in a predetermined sequence by a series of dipole, quadrupole and solenoid magnets. The imager consists of 0.194 mm pixels laid out in 1576 rows by 2048 columns, binned 4x4 to achieve 60 fps projection image operation with 16 bits dynamic range. These are intended for application with free breathing patients during ordinary linac C-arm radiotherapy with modest modifications to typical system hardware or to standard clinical treatment delivery protocols. The sliding digital tomosynthesis reconstruction is completed after every 10 projection images acquired at 60 fps, but using the last 19 such projection images for each such reconstruction at less than 8 mAs exposure per 3D rendered frame. Comparisons, to “ground truth” optical imaging and to diagnostic 4D CT (10 phase) images, are being used to determine the accuracy and limitations of the various versions of this new “19 projection image x-ray tomosynthesis fluorooscopy” motion tracking technique.

We examine incidents in which Japanese businesses are implicated in corporate scandals. Such firms suffer statistically significant losses in their market values. Given the negligible legal and regulatory penalties for Japanese companies, we interpret the results as convincing evidence on the size of reputational losses. We also compare our results to those found in U.S. studies. The average negative abnormal stock price reaction is larger in Japan than in the United States. Moreover, they are negative and statistically significant even when it is not obvious that the firm violated an implicit or explicit contract with the damaged party.

A giant fusiform aneurysm of the basilar artery was present in a 10-year-old boy with a 2-year history of intermittent headaches and the acute onset of neurologic signs. Elevated sedimentation rate, cerebrospinal fluid pleocytosis, and an apparent response to corticosteroid therapy suggest a chronic inflammatory vascular process. The uniqueness of this aneurysm in a child and the possible underlying arteriopathies are discussed.

Previous reports of hypocalcemia and hyperphosphatemia following use of phosphate enemas have either been in patients with renal disease or followed prolonged abuse of these products. The two patients described here had marked elevation of serum phosphate and concomitant lowering of serum calcium secondary to absorption of phosphate from a single administered enema. Associated moderate dehydration resulted in poor renal excretion of the absorbed phosphate and prolongation of hypocalcemia. Hydration was effective in permitting clearance of phosphate and restoration of normocalcemia.