Recent work has demonstrated considerable benefits of intracolonial genetic diversity for the productivity of honeybee colonies: single-patriline colonies have depressed foraging rates, smaller food stores and slower weight gain relative to multiple-patriline colonies. We explored whether differences in the use of foraging-related communication behaviour (waggle dances and shaking signals) unde...

We investigated the in vitro effects of 4-hydroperoxycyclophosphamide (4-HC) on human hemopoietic stem cells. Marrow cells were exposed to 4-HC and then assayed for mixed (CFU-GEMM), erythroid (BFU-E), megakaryocyte (CFU-M), and granulocyte-macrophage (CFU-GM) colony forming cells. We found that highly proliferative colony forming cells, especially CFU-GEMM and BFU-E, were relatively spared by ...

Brief introduction to the colonies, the grammars systems interacting on common passive environment with components individual ly producing finite languages, is presented. An overview of the topic is completed by large number of references. I(eywords: grammar system, colony, generative power, hierarchy

Honeybees, Apis spp., maintain elevated temperatures inside their nests to accelerate brood development and to facilitate defense against predators. We present an additional defensive function of elevating nest temperature: honeybees generate a broodcomb fever in response to colonial infection by the heat-sensitive pathogen Ascosphaera apis. This response occurs before larvae are killed, sugges...

The development of transformed colonies and concomitant changes in proliferative and nonproliferative cell compartments were studied in rat tracheal epithelial (RTE) cell cultures following exposure to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Primary RTE cells were plated onto 3T3 feeder layers and treated with MNNG (0.25 micrograms/ml) or solvent. Seven days later, the feeder cells were re...

Colonies of Trioxys pallidus Haliday (Hymenoptera: Aphidiidae) were collected from California walnut orchards during 1985-86 and screened for variability of responses to azinphosmethyl. Variability was found and laboratory selection was initiated with four colonies. All colonies responded to selection; after 7 to 12 selections, three colonies were combined (Select colony) and selection was cond...

We report the growth in plasma clot culture of megakaryocyte colonies from adult bone marrow cells with the use of four different sources of erythropoietin (Ep) as the stimulating factor. A major proportion of the megakaryocyte colonies (75%) were pure, while the others were mixed, involving erythroblasts and megakaryocytes. Ultrastructural studies have shown that the maturation of megakaryocyt...

Honey bee queens mate with many males, creating numerous patrilines within colonies that are genetically distinct. The effects of genetic diversity on colony productivity and long-term fitness are unknown. We show that swarms from genetically diverse colonies (15 patrilines per colony) founded new colonies faster than swarms from genetically uniform colonies (1 patriline per colony). Accumulate...

Ant colonies are commonly thought to have a stable and simple family structure, with one or a few egg-laying queens and their worker daughters. However, recent genetic studies reveal that the identity of breeding queens can vary over time within colonies. In several species, some queens are apparently specialized to enter established colonies instead of initiating a new colony on their own. The...

The ability of 258 strains of Staphylococcus aureus and 132 strains of S. epidermidis to produce L-form colonies in a standard environment was investigated. Production of these colonies by S. aureus was correlated with their phage type. Phage type 7 strains produced L-forn colonies in larger numbers and more consistently than those of phage type 80/81. No L-form colonies were produced by the S....