Evidence for the involvement of quinone rings in reactions of some coals with tetralin

Model compounds representing a variety of hydrocarbon groups and most of the oxygen-containing functional groups have been tested for reactivity with tetralin at 400° C. Only the quinones were capable of oxidizing tetralin to naphthalene. Anthraquinone is completely deoxygenated to anthracene. Evidence for homolysis of carbon-carbon bonds was found only in the case of dibenzyl, and this was not accompanied by oxidation of tetralin. The extractability of subbituminous coals with the non-reducing solvent, diphenyl-diphenyl ether eutectic, is correlated with oxygen content and depth of burial. It is suggested that oxidized coals near the surface contain quinone rings, and that dissolution by tetralin is primarily then due to lowering of the solvent parameter as a consequence of deoxygenation.     

Pharmacodynamics of some individual milkweed cardenolides fed to larvae of the monarch butterfly (Danaus plexippus L.)

Adult monarch butterflies,Danaus plexippus L. (Lepidoptera: Danaidae), store only some of the cardenolides present in the larval milkweed (Asclepiadaceae) host. Feeding known doses of individual cardenolides to 4th instar monarch larvae led to more efficient larval tissue incorporation at low doses than at high ones, and favored storage of cardenolide glycosides over genins. A qualitative regulation also occurs during larval feeding; calactin and calotropin were stored as such but uscharidin was rapidly converted to a mixture of calactin and calotropin which were the forms stored by the larvae. Two genins, uzarigenin and digitoxigenin, were stored by larvae as polar cardenolide metabolites.Research supported by National Science Foundation grants DEB 7514266 and DEB 7514266-AO2 (U.C. Davis) and DEB 7514265 (Amherst College).     

Comparative gamma radiation sensitivity of Tribolium madens (Charpentier) and T. castaneum (Herbst)

The effects of gamma radiation doses between 5 and 100 krad on all metamorphic stages of Tribolium madens and T. castaneum were studied. Results from the two species were similar although T. madens appeared to be more radiosensitive. The development of adults from treated eggs and larvae was prevented by 5 krad in T. madens and by 10 krad in T. castaneum. Some adults emerged from treated pupae at all treatment levels, but no reproduction occurred at 20 krad or above. Adult females of both species were more sensitive to the sterilizing effects of gamma radiation than were males, but sterility of both sexes was effected at doses of 30 krad and above. Control of these two species appears feasible with levels of radiation currently approved for treatment of stored-grain insects in wheat and wheat flour.     

Biostratigraphic correlation within IGCP Project 148

Although embryonic, quantitative biostratigraphy is alive and hopefully well. The potential for future growth clearly is present and will be fostered by IGCP Project 148 which is charged with the development of algorithms as well as the evaluation of methods through rigorous case studies.Sequencing methods produce a dimensionless list of events. Such a list is effective for correlation but yields little information about environments or discontinuities between different faunal zones. Quantified assemblage zones provide information about environments and stratigraphy although the resulting correlations usually are less precise. Assemblage zones also point out the locations of faunal discontinuities. The information contained in an evolutionary sequence consists of a continuous or discontinuous spectrum of morphological or taxonomic changes in time and space, depending on the method of analysis and the evolutionary lineage or lineages under study.     

Laser action from two dipyrrinone dyes under flash-lamp pumping

Two quasi-aromatic compounds, namely, two dipyrrinone dyes (Xanthoglow and Kryptoglow), exhibited strong fluorescence. Therefore they were tested for laser action under flash-lamp pumping. These two dyes outperformed Coumarin 540A and exhibited a high degree of photostability when dissolved in 1,4-dioxane. However, in all other solvents used, considerable photodecomposition was observed.     

Life tasks, self-concept ideals, and cognitive strategies in a life transition.

This paper reports on data from a longitudinal study in which normative life tasks and individuals' personal versions of those tasks are investigated in the context of students making the transition from home and high school to college life. Analyses focus both on common patterns of life-task appraisal in interpersonal and achievement domains and on differences in the self-concepts and cognitive strategies that individual students bring to bear as they confront these normative pressures (Cantor & Kihlstrom, 1987). In particular, we investigate the impact of students' actual-ideal self-discrepancies (Higgins, Klein, & Strauman, 1985) on subjective stress and satisfaction in achievement and interpersonal life-task domains and suggest that self-concept discrepancy negatively affects adjustment in the achievement domain and positively affects social outcomes. Students using a defensive-pessimism strategy motivated themselves by confronting their anxieties in advance of stressful tasks, whereas those using an optimistic strategy assumed the best until proved otherwise—protecting self-esteem after the fact in the event of disappointment (Norem & Cantor, 1986a, 1986b). This analysis, thus, begins at the level of normative "readings" of life tasks in a shared transition period and gradually moves toward consideration of how individuals navigate those tasks in personally meaningful ways. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

PLA2 promotes fusion between PMN-specific granules and complex liposomes

Neutrophil stimulation results in the activation of a variety of phospholipases, including phospholipase A2 (PLA2), which releases arachidonic acid from the 2 position of membrane phospholipids, leaving a lysophospholipid. Because arachidonic acid is known to be a potent fusogen in vitro, we examined the effect of metabolism by PLA2 on the fusion of complex liposomes (liposomes prepared with a phospholipid composition similar to that found in neutrophil plasma membrane). We observed that PLA2 augmented the fusion of complex liposomes with each other as well as with specific granules isolated from human neutrophils, lowering the Ca2+ requirement for fusion by three orders of magnitude. Furthermore, although lysophospholipids inhibited fusion, the incorporation of arachidonic acid into liposome membranes overcame the inhibitory effects of the lysophospholipids. Thus with PLA2 and annexins we were able to obtain fusion of complex liposomes at concentrations of Ca2+ that are close to physiological. Our data suggest that the activation of PLA2 and the generation of arachidonic acid may be the major fusion-promoting event mediating neutrophil degranulation.