Pneumothorax. A complication of fine needle aspiration of breast tumors

Of 1,666 patients who underwent fine needle aspiration for breast lumps, 4 developed pneumothorax as a complication. The incidence of this complication in our patients is 1:417. The clinical manifestations were immediate chest pain, shoulder pain and, occasionally, dyspnea that developed later. Observation is sufficient treatment in most patients, and rarely is drainage of the pneumothorax required.     

Reconstruction of diffusion coefficients in the problem of carbonitriding

The uniqueness of the determination of carbon and nitrogen diffusion coefficients is found for the process of carbonitriding with complete and abbreviated information on the concentration fields.M. V. Lomonosov Moscow State University, Russia. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 66, No. 4, pp. 480–483, April, 1994.     

Oxidation of boron silicide and materials based on it

Boron silicide and compounds based on it containing titanium, chromium, nickel, and yttrium and scandium oxides are studied for their oxidation in air from room temperature to 1300°C. It is shown that chromium boride markedly improves the heat resistance of B₄Si over a wide temperature range (700–1300°C) probably as a result chromium-oxide dissolution in borosilicate glass and alteration of its structure. A favorable effect of yttrium and scandium oxides as well of nickel silicide appears at above 100°C as a result of forming complex oxide compounds in the scale.     

L-arginine reduces kidney collagen accumulation and N-epsilon-(carboxymethyl)lysine in the aging NMRI-mouse

BACKGROUND: The aging process leads to glomerular basement membrane (GBM) thickening due to increased collagen accumulation. This mechanism can be explained by the nonenzymatic glycosylation hypothesis of collagen aging. We have published the positive effect of L-arginine on glucose-mediated cross-linking, and if the nonenzymatic glycosylation hypothesis of aging holds, the pharmacological effect of L-arginine on glucose-mediated cross-links in the aging Hannover NMRI mouse can be expected. METHODS: Animals were given L-arginine 50 mg/kg body weight/day orally and compared to a control group without treatment. RESULTS: Electron microscopical measurement of the GBM thickness showed significant differences between controls (4920 +/- 1680 A) and the experimental group (2345 +/- 815 A). Determination of the total kidney collagen content based upon 4-trans hydroxyproline revealed 13.9 +/- 3.9 mg/100 mg kidney weight (kw) in the untreated group versus 7.9 +/- 4.2 mg/100 mg kw in the treated group. For solubility studies based upon hydroxyproline determination, collagen was eluted by pepsin digestion. This revealed 18.7 +/- 3.9 mg/100 mg kw in the controls versus 7.8 +/- 4.8 mg/100 mg kw in the treated group. HPLC analysis of N-epsilon-(carboxymethyl)lysine (CML) showed in the treated group (1.847 +/- 0.247 nM/microM hydroxyproline) significantly lower concentrations than in the untreated group (3.399 +/- 0.349 nM/microM hydroxyproline). On sodium dodecyl sulfate (SDS) polyacrylamidegel electrophoresis, the eluates of the treated animals showed less high molecular weight material than their untreated mates. CONCLUSIONS: We cannot discriminate between the probable mechanisms of cross-linking but we clearly can state that L-arginine reduces cross-linking and collagen accumulation in aging collagen type IV accompanied and strongly associated with decreased CML content.     

Object and texture classification using higher order statistics

The problem of the detection and classification of deterministic objects and random textures in a noisy scene is discussed. An energy detector is developed in the cumulant domain by exploiting the noise insensitivity of higher order statistics. An efficient implementation of this detector is described, using matched filtering. Its performance is analyzed using asymptotic distributions in a binary hypothesis-testing framework. The object and texture discriminant functions are minimum distance classifiers in the cumulant domain and can be efficiently implemented using a bank of matched filters. They are immune to additive Gaussian noise and insensitive to object shifts. Important extensions, which can handle object rotation and scaling, are also discussed. An alternative texture classifier is derived from a ML viewpoint and is statistically efficient at the expense of complexity. The application of these algorithms to the texture-modeling problem is indicated, and consistent parameter estimates are obtained     

Dislocations in strained layers: The Ge-Si system

The Ge-Si on Si epilayer system, besides being an interesting technological system in its own right, is a superb model for strained-layer studies. The point defect and symmetry defect structures associated with compound semiconductors can be avoided, allowing a focus on the mechanics of the system. Dislocation sources, glide behavior, and performance effects have been examined for strained-layer systems. Surprises have appeared along the way, but these materials are now becoming characterized well enough for industrial device applications.     

Effect of the method of activation on properties of zeolite-containing hydrotreatment catalysts

Translated from Khimiya i Tekhonologiy Topliv i Masel, No. 3, pp. 33–34, March, 1992.     

Harmonical characterization of a microstrip bend via the finitedifference time domain method

A 90° microstrip bend is characterized using a time-frequency method based on the finite-difference-time-domain (FDTD) method. Time evolution of the currents generated by FDTD are Fourier transformed to lead to S-parameters and the radiated powers characteristic of the microstrip bend. The method for calculating both radiation and surface wave losses is developed for microstrip structures. The results of the 90° microstrip bend are compared with the results of the mitered microstrip bend