Metastatic renal cell carcinoma presenting as an aural polyp

Renal cell carcinoma may metastasize to the head and neck region at different stages of its evolution. We present a case of an undiagnosed renal cell carcinoma presenting as an ear polyp, and discuss the difficulties of the diagnosis and the management of these tumours.     

Retained fetal lung liquid in congenital lobar emphysema: a possible predictor of polyalveolar lobe

The purpose of this study was to determine whether retention of fetal lung liquid is more prevalent in polyalveolar congenital lobar emphysema than in conventional congenital lobar emphysema. Two patients with congenital lobar emphysema were prospectively identified in a 3-year period. Twenty-five such patients were identified in a retrospective study covering 39 years. Medical records were available for 22 patients who had 23 emphysematous lobes. Both babies from the prospective study and six subjects from the retrospective group had respiratory symptoms and underwent chest X-ray in the first day of life. Six of the eight babies with respiratory symptoms and chest imaging in the first day of life had retention of fetal lung liquid in an emphysematous lobe. All six of these lobes were polyalveolar. The lobe in one child was a polyalveolar lobe but without retained fetal lung liquid, and one child exhibited conventional lobar emphysema also without retained fetal lung liquid. One polyalveolar lobe caused no neonatal symptoms and was not imaged until the child was 3 months old. No baby with conventional lobar emphysema was shown to have retained fetal lung liquid. There seems to be a correlation between polyalveolar lobe and onset of respiratory symptoms in the first day of life. Retention of fetal lung liquid within the affected lobe was documented only in cases of polyalveolar lobe.     

Reliability Potential Of Epoxy Based Encapsulants For Automotive Applications

Automotive under-the-hood electronics often have to withstand temperatures up to 175 °C in combination with harsh environment conditions. This paper gives an overview about the reliability potential of epoxy based encapsulants for automotive applications. Therefore the resistance of epoxy molding compound against typical automotive fluids at temperature of use is analyzed. Six epoxy molding compounds available on the market, showing high temperature automotive potential have been carefully selected to undergo a media resistance testing. For this purpose a dedicated mold tool has been designed and manufactured to prepare these encapsulants for material testing. Thermo-mechanical, mechanical and thermal properties had been determined in initial state directly after molding and after storage in aggressive fluids typical for automotive applications as e.g. gas oil, automatic transmission fluid (ATF), brake fluid or accumulator acid at the respective temperature of use.     

A versatile data acquisition system for time resolved X-ray scattering using gas proportional detectors with delay line readout

A data acquisition system for time resolved X-ray scattering experiments using linear, quadrant or area gas proportional detectors with delay line readout based on commercially available hardware (National Instruments) is described. The system can easily be configured for recording data from point detectors (e.g. photomultipliers and photodiodes) and/or ancillary data only. Applications involving measurements with two different types of time to digital converters illustrate the features and performances of the system.     

Fluoride catalysis at 175°C. of the reaction: Glycerol plus fatty acid

1. In uncatalyzed reactions the esterification of stearic, oleic, and linolenic acid proceeded at the same general rate though the speed was somewhat enhanced as the degree of unsaturation of the fatty acid increased. None of the reactions went to completion, after 15 hours being 72%, 83%, and 84%, respectively, completed. Only a small fraction of the distearate was converted to the triglyceride; a greater amount of the dioleate was esterified to the trioleate and about half the dilinolenate was changed to the trilinolenate.
2. Of 15 metallic fluorides studied, all afforded some catalysis, but only antimony trifluoride and zinc and cobalt fluorides were outstanding. Antimony trifluoride was the most active although in large amount it caused severe decomposition and charring of the products. Zinc fluoride had the best general properties, approaching antimony trifluoride yet causing practically no decomposition even in high concentration. Its activity was enhanced with an increase in amount, the best concentration apparently being 0.1 mole per 100 grams fatty acid. Antimony trifluoride was also better in larger amount within limits, but cobalt fluoride did not exhibit this property.
3. With zinc fluoride as catalyst the reactions of stearic, oleic and linolenic acids after 15 hours were 95%, 94%, and 92%, respectively, completed. At least three-fourths of the diglycerides were converted to triglycerides. From a study of reaction velocities, zinc fluoride caused the monoglyceride to form at a rate approximately four times that of the uncatalyzed reaction and the diglyceride at a six-fold rate. The triglyceride was formed at an almost undiminished rate whereas in the uncatalyzed reaction the formation of triglyceride was diminished rapidly.
4. Unsaturation and viscosity were not affected seriously in the presence of the fluorides except antimony trifluoride. Certain other fluorides caused severe darkening but without accompanying serious decomposition.

     

Terahertz characterisation of building materials

To obtain realistic models for propagation channels in future pico-cellular indoor terahertz communication systems it is necessary to know the reflective properties of building materials found in a typical office environment. The angular dependent reflection coefficients of different building materials were determined using terahertz time-domain spectroscopy in transmission geometry and Fresnel's equations. This approach is more efficient than a set of measurements in reflection geometry for different angles. Verification of the method with a set of such reflection measurements shows an excellent agreement.