An extremely energetic cosmic ray observed by a surface detector array.

Cosmic rays are energetic charged particles from extraterrestrial sources, with the highest-energy events thought to come from extragalactic sources. Their arrival is infrequent, so detection requires instruments with large collecting areas. In this work, we report the detection of an extremely energetic particle recorded by the surface detector array of the Telescope Array experiment. We calculate the particle's energy as [Formula: see text] (~40 joules). Its arrival direction points back to a void in the large-scale structure of the Universe. Possible explanations include a large deflection by the foreground magnetic field, an unidentified source in the local extragalactic neighborhood, or an incomplete knowledge of particle physics.

Effects of dose, pH, and osmolarity on nasal absorption of secretin in rats. II: Histological aspects of the nasal mucosa in relation to the absorption variation due to the effects of pH and osmolarity.

Nasal absorption of secretin in rats was enhanced in an acid solution, and the maximum absorption was observed at a sodium chloride solution molarity of 0.462. In order to examine reasons for the variation of absorbability caused by the change of pH and osmolarity in secretin preparations, both a pretreatment study, in which the nasal mucosa was treated with placebo prior to the administration of a secretin preparation, and a histological study were conducted in rats. The nasal absorption of secretin was determined by measuring the increased secretin of pancreatic juice. Similar profiles of nasal absorption, both after intranasal administration of secretin preparations and as a result of pretreatment effects, were obtained in studies of the effects of pH and osmolarity. However, in the pH-effect study, the absorption with the use of active preparations was observed to be significantly larger than that with the pretreatment effect below a pH of 4.79, and significantly smaller than that with the pretreatment effect at a pH of 7 to 8. The results of histological studies revealed structural changes of the epithelial cells of the nasal mucosa at pH 2.94, and shrinkage of epithelial cells was observed at a sodium chloride solution molarity of 0.462.

The enzymatic spectrofluorimetric determination of uric acid in microsamples of plasma by using p-hydroxyphenylacetic acid as a fluorophor.

A sensitive spectrofluorimetric micromethod for the determination of uric acid is presented together with its application to human and rat plasma. The method is based on the reactions or uricase and peroxidase coupled with p-hydroxyphenylacetic acid as a fluorophor. There is a very wide range of proportionality between the concentration of uric acid and the increase of fluorescence intensity. 10 ng of uric acid is still determinable. At most 25 mul of human or 50 mul of rat plasma is sufficient to obtain the accurate valve of endogenous plasma uric acid concentration. The uric acid levels of normal human and rat plasma measured by present method were within the ranges of concentrations previously reported. A comparative study of this method with a standard assay method is also presented.