Corrosion behavior of ultrafine-grained AA2024 aluminum alloy produced by cryorolling

The objectives of this study were to produce ultrafine-grained (UFG) AA2024 aluminum alloy by cryorolling followed by aging and to evaluate its corrosion behavior. Solutionized samples were cryorolled to ~85% reduction in thickness. Subsequent aging resulted in a UFG structure with finer precipitates of Al₂CuMg in the cryorolled alloy. The (1) solutionized and (2) solutionized and cryorolled samples were uniformly aged at 160℃/24 h and were designated as CGPA and CRPA, respectively; these samples were subsequently subjected to corrosion studies. Potentiodynamic polarization studies in 3.5wt% NaCl solution indicated an increase in corrosion potential and a decrease in corrosion current density for CRPA compared to CGPA. In the case of CRPA, electrochemical impedance spectroscopic studies indicated the presence of two complex passive oxide layers with a higher charge transfer resistance and lower mass loss during intergranular corrosion tests. The improved corrosion resistance of CRPA was mainly attributed to its UFG structure, uniform distribution of fine precipitates, and absence of coarse grain-boundary precipitation and associated precipitate-free zones as compared with the CGPA alloy.     

An assessment of the effect of hormone and neurotransmitters on adenine and guanine derivatives simultaneously in rat brain cortical slices.

A A 2-dimensional thin-layer method has been developed for the separation on cellulose of adenine and guanine derivatives. Using incubated rat cerebral cortex slices it was shown that noradrenaline and acetylcholine stimulated cAMP and cGMP production respectively but glutamate and gamma-aminobutyric acid stimulated production of both cyclic nucleotides.     

Neocortical transplants in the rat brain: an ultrastructural study

Summary Electron microscopic analysis of neocortical transplants in the cerebellum of the host animals showed that the nerve cells, glial cells, and neuropil of the transplants were normal. These transplants showed anatomical integration with the host brain through various regions of interface. Neuropil interfaces were found to have a high density of synaptic profiles, and medullary interfaces had a very small number of synaptic profiles.Acknowledgment. Research supported by Contract No. N00014-83 from the Office of Naval Research, Department of the Navy to E.N.A., and N.I.H. Research Grant No. NS-08817 to G.D. Das.     

In vitro demonstration of peroxidase activity in the fish kidney soluble supernatant and its physiological importance

Zusammenfassung In der Kopfniere des TeleostiersAnabes testudineus wurde eine besonders hohe Peroxidase-Aktivität nachgewiesen, insbesondere deren Iodid-Oxydation zu Tri-Iodid.     

Stereotaxic technique for transplantation of neural tissues in the brain of adult rats

Summary A technique of neural transplantation in the brains of adult animals, using stereotaxic apparatus, is described. It facilitates transplantation of neural tissues of small volumes in precisely defined structures of the host brain, and yields a high percentage of successful transplantations.Supported by N.I.H. Research grant No. NS-08817. Suggestions from Drs N. Mangini, M. M. Oblinger and J. Weibers on various aspects of this procedure are gratefully acknowledged.     

Response due to 0 somatic antigen ofShigella dysenteriae in rabbits

Zusammenfassung Hochgereinigtes Antigen vonShigella dysenteriae bewirkte eine signifikante Temperatursteigerung in Kaninchen.     

Chemical genetic discovery of targets and anti-targets for cancer polypharmacology

The complexity of cancer has led to recent interest in polypharmacological approaches for developing kinase-inhibitor drugs; however, optimal kinase-inhibition profiles remain difficult to predict. Using a Ret-kinase-driven Drosophila model of multiple endocrine neoplasia type 2 and kinome-wide drug profiling, here we identify that AD57 rescues oncogenic Ret-induced lethality, whereas related Ret inhibitors imparted reduced efficacy and enhanced toxicity. Drosophila genetics and compound profiling defined three pathways accounting for the mechanistic basis of efficacy and dose-limiting toxicity. Inhibition of Ret plus Raf, Src and S6K was required for optimal animal survival, whereas inhibition of the 'anti-target' Tor led to toxicity owing to release of negative feedback. Rational synthetic tailoring to eliminate Tor binding afforded AD80 and AD81, compounds featuring balanced pathway inhibition, improved efficacy and low toxicity in Drosophila and mammalian multiple endocrine neoplasia type 2 models. Combining kinase-focused chemistry, kinome-wide profiling and Drosophila genetics provides a powerful systems pharmacology approach towards developing compounds with a maximal therapeutic index.