In this paper we describe a natural extension of the well-known ρ-labeling of graphs (also known as rosy labeling). The labeling, called product rosy labeling, labels vertices with elements of products of additive groups. We illustrate the usefulness of this labeling by presenting a recursive construction of infinite families of trees decomposing complete graphs.

A multilateral approach that includes both biotic and climatic data was developed to detect the main variables that affect the ecology and population dynamics of woolly apple aphid Eriosoma lanigerum (Hausmann). Crawlers migrated up and down the trunk mainly from spring to autumn and horizontal migration through the canopy was observed from May to August. Winter temperatures did not kill the ca...

aphids are among important agricultural pests. the pest's evolutionary tendency towards a loss of taxonomically useful characteristics, as well as morphological plasticity due to host type and as a result of environmental factors, make a morphological identification of aphids difficult, whereas exact identification is indispensable for managment of these pests. thus, modern identification ...

53. WEBB, K. L. & J. W. A. BURLEY. 1962. Sorbitol translocation in apple. Science 137: 766. 54. WVEATHERLEY, P. E., A. J. PEEL, & G. P. HILL. 1959. The physiology of the sieve tube. Preliminary experiments using aphid mouth parts. J. Exptl. Botany 10: 1-16. 55. AXANG, T. T. 1961. A study of tranislocation of of photosynthate in sugar cane plants with C14 anid P;. Rept. Taiwan Sugar Exp. Sta. 23...

The rosy locus in Drosophila melanogaster codes for the enzyme xanthine dehydrogenase (XDH). Previous studies defined a "control element" near the 5' end of the gene, where variant sites affected the amount of rosy mRNA and protein produced. We have determined the DNA sequence of this region from both genomic and cDNA clones, and from the ry+10 underproducer strain. This variant strain had many...