In Japan, most cases of malignant lymphoma arising in the thorax are pyothorax-associated lymphoma, which develops in patients who have undergone artificial pneumothorax, used in the past as surgical therapy for pulmonary tuberculosis. Pyothorax-associated lymphoma consist mostly of diffuse large B-cell lymphoma and have a strong association with EBV. Herein is reported the case of a diffuse large B-cell lymphoma arising in the left thoracic wall after left lung resection for squamous cell carcinoma and chest wall reconstruction with polyethylene terephthalate (PET) surgical mesh. The tumor was found 20 years after the operation and was confined to the chest wall adjacent to the PET mesh. The patient did not have a clinical history of pyothorax after surgery. The lymphoma cells were of the large cell type and were positive for CD20, EBV-encoded small RNA--in situ hybridization, LMP-1 and EBNA-2. The present case demonstrates that EBV-related B-cell lymphoma can occur after surgery other than artificial pneumothorax. In the present case, long-standing chronic inflammation induced by PET mesh may have been associated with the development of lymphoma.

The current-voltage curve of an atomically flattened hydrogen-terminated p-Si(111) surface is studied in 0.1 M ammonium borate solution in a potential region from the onset of the anodic current to about 3 V vs. Ag/AgCl. Three anodic current peaks are observed in this potential region. A deconvolution of the current-voltage (I-V) curve revealed that these three peaks are related to the oxidation of three Si monolayers from the surface. The current due to the oxidation of the first monolayer consists of two components with different peak potentials. Supported by Fourier transform infrared measurements, the component at the lower potential is attributed to the oxidation of Si-Si back bonds and the one at higher potential to the oxidation of Si-H bonds. The shape of the I-V curve is sensitive to the surface pretreatment, and we consider the shape to be a good indicator of the Si surface conditions. © 2003 The Electrochemical Society. All rights reserved.

An x-ray tube is described whose attributes of beam coherency, low penetrating power and high intensity were required for the radiography of cigarettes, but it is thought to have a potential usefulness also in the field of radiobiology and Jnedium energy crystallography. At full load the tube has a rating of 300 w at 15 kv. The diameter of the source, as determined by resolution experiments, is 0.61 mm, so that the specific target loading is 1 3 03 kw m-'.

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By detecting vibrational frequencies for N-H structures, the chemical states of N atoms at silicon nitride on silicon, SiN/Si, and silicon oxide with nitrogen on silicon, SiO(N)/Si, systems were deduced after being chemically decollated with H atoms in dilute HF solution.Using the fact that the decollation was associated with the dissolution of these films, we obtained their depth profile. The frequency was increased to an extent of 10 cm -1 by the existence of a thin oxide layer between the SiN layer and the Si substrate. The N-H structure bound to the Si substrate was observed at 3390 cm -1 just before the completely removal of the surface layer.We also observed the NH structure of crystal SiN form, whose frequency was unchanged to be 3325 cm -1 . The same technique was applied to detect the chemical structure of the N atoms in an ultra-thin SiO(N) with 5% of the N atoms. The frequency peak of the bulk N structure was observed with that of OH structures. The peak was shifted from 3375 cm -1 to 3405 cm -1 at the interface region, suggesting densification of the film in the interface region. Prior to complete removal, we observed the surface state of the N atoms and the H atoms. Then the frequency of the NH was unaffected by the film formed with the various methods. No SiH structure was observed on the resultant film surface during etching.