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A material development project was initiated to develop a new zirconium alloy, outside the ASTM specifications for Zircaloy-2 and Zircaloy-4, with optimized hydriding and corrosion properties for both boiling water reactors and pressurized water reactors. A number of different alloys were manufactured. These alloys were long-term corrosion tested in autoclaves at 400 C in steam. Also, a 520 C/24 h steam test was carried out. The zirconium metal microstructure and the chemistry of precipitates were characterized by analytical electron microscopy. The metal matrix chemistry was determined by atom probe analysis. The paper describes the correlations between corrosion material performance and zirconium alloy microstructure.

Abnormal repetitive behavior, including stereotypy, is often observed in conjunction with developmental, neuropsychiatric, and genetic disorders. The present work employed the deer mouse model of spontaneous and persistent stereotypy to identify basal ganglia involvement in the mediation of these abnormal behaviors. To evaluate the hypothesis that stereotypy is expressed in these mice due to alterations in the activity of cortico-basal ganglia motor circuits, intrastriatal pharmacological manipulations aimed at attenuating the spontaneously emitted stereotypy were performed. Bilateral striatal infusion of the NMDA or dopamine D(1) receptor antagonists MK-801 or SCH23390, respectively, produced a substantial reduction in levels of stereotypic jumping without inhibiting nonstereotypic motor behavior. These findings support the hypothesis that environmentally related stereotypy is expressed as a consequence of elevated feedback activity occurring along motor circuits of the basal ganglia.

Although total limb volume measurements are used to track the progress of lymphedema and its treatment, these measurements can be confounded by changes other than fluid excess namely muscle or fat gain. Bioelectrical impedance analysis (BIA) is a technique that specifically quantifies both total body fluid and extracellular fluid in extremities. Whereas BIA has potential as a quick, inexpensive, and quantitative technique to measure directly fluid gain or loss from lymphedema, it also has certain shortcomings that must be addressed before it can be validated. this paper examines the back-ground that explains why measuring total limb volume is insufficient to quantify the extent of peripheral lymphedema and explores the advantages and drawbacks of using BIA for this purpose.

An investigation of the size and suitability for the transplantation procedures of the knee blood vessels was made in 20 adult dogs with 40 extremities using the technique of injection of the arterial network through the femoral artery with the mixture of the methacrylic resin (SIGMAL R "Galenika", Belgrade) and the red ink. When the polymerisation of injected methacrylic resin was completed the specimens were exposed to either chemical or biological maceration of the tissues. Thirty-five specimens were chemically macerated using either 30% solution of hydrochloride acid or 40% potassium hydroxide. With this method bones were also destroyed and only the methacrylic vascular cast remained unaffected. Five specimens were exposed to the biological maceration using the insects (Dermestes vulpinus). This method proved to be better as the bones elements were not destroyed which allowed more precise study of vessel relations and topography. Calibre of the arteries was measured using the micromethod MEBA (Zagreb) with the accuracy of 0.01 mm. The main arterial vessels of the knee joint on the medial side are aa. saphena, genus descendes (branches of the femoral artery, then a. genus descendens (branches of the femoral artery, then a. genus medialis (branch of the popliteal artery), and on the lateral side are a. caudalis femoris distalis, (branch of the femoral artery), a genus lateralis (branch of the popliteal artery) and recurrent branches of the a. tibialis cranialis. Calibre of the femoral and popliteal arteries was over 2 mm which means that they are suitable for macrosurgical sutures, while the calibre of all other arteries was under 2 mm, and it is concluded that they are suitable only for microsurgical sutures.