University of Memphis

About: University of Memphis is a education organization based out in Memphis, Tennessee, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 7710 authors who have published 20082 publications receiving 611618 citations. The organization is also known as: U of M.

Latent structure of facets of alcohol reinforcement from a behavioral economic demand curve

Abstract: Rationale Behavioral economic demand curves are quantitative representations of the relationship between consumption of a drug and its cost. Demand curves provide a multidimensional assessment of reinforcement, but the relationships among the various indices of reinforcement have been largely unstudied.

On the Evolution of Genome Size of Birds

Abstract: We measured genome size (nuclear DNA content) by fluorescence flow cytometry in 55 species of birds representing 12 different orders. Similar studies were performed in approximately 100 species by laboratories using absorption cytophotometry of Feulgen-stained nuclei. Although there have been apparent discrepancies in the assigned values for the species used as a reference, the values obtained in the different laboratories are generally in agreement. When the data are standardized in relation to a diploid (2C) value of 2.5 picograms (pg) of DNA for the domestic chicken (Gallus gallus domesticus), the mean for DNA content in 135 species representing 17 orders is 2.82 +/- 0.33 (SD) pg with a range of 2.0-3.8 pg. Thus the genome size of birds is the most conservative of any vertebrate class and, all values considered, is smaller and more uniform in size than previous estimates would indicate. This could be explained by a previously unexplored hypothesis: that the genome of birds has evolved from a small ancestral genome that was reduced before emergence of the protoavian.

Oxidative stress response to aerobic exercise: comparison of antioxidant supplements.

Abstract: BLOOMER, R. J., A. H. GOLDFARB, and M. J. MCKENZIE. Oxidative Stress Response to Aerobic Exercise: Comparison of Antioxidant Supplements. Med. Sci. Sports Exerc., Vol. 38, No. 6, pp. 1098 – 1105, 2006. Purpose: To compare the effects of two antioxidant formulas on biomarkers of oxidative stress before and after aerobic exercise. Methods: Aerobically trained men (N =2 5) and women (N = 23) were assigned to one of three treatments: 400 IU of vitamin E + 1 g of vitamin C (V; N = 15), a fruit and vegetable juice powder concentrate (FV; N =1 6), or ap lacebo (P;N = 17). Subjects ran for 30 min at 80% V u O2max before, after 2 wk of supplementation, and after a 1-wk washout period. Blood samples were taken before and immediately after exercise and analyzed for protein carbonyls (PC), malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), and vitamins C and E. Results: The V treatment increased plasma vitamin C and E after 2 wk (P e 0.05), with no change in the FV or P. Postexercise PC values were elevated for all treatments after all exercise bouts (P G 0.0001). Both V and FV attenuated the exercise-induced increase in PC after 2 wk of supplementation (V = 21%, FV = 17%), and after the 1-wk washout (V = 13%, FV = 6%) compared with P (P G 0.05), with no differences between V and FV. MDA was unaffected by exercise and treatment. A treatment main effect for 8-OHdG was noted, with values for V lower than for FV and P (4.5 T 2.5, 5.5 T 2.7, and 6.0 T 2.5 ngImL j1 , respectively; P = 0.0002). No exercise session or time main effect was noted for 8-OHdG, suggesting that the lower mean value for the V treatment group was not a result of the supplementation. Conclusion: These data suggest that V and FV supplementation for 2 wk can attenuate the rise in PC after 30 min of aerobic exercise, even after a 1-wk washout, without an impact on plasma MDA or 8-OHdG. Key Words: DIETARY SUPPLEMENTS, FREE RADICALS, PROTEIN CARBONYLS, MALONDIALDEHYDE, 8-OHDG

Phylogeny and classification of Cucujoidea and the recognition of a new superfamily Coccinelloidea (Coleoptera: Cucujiformia)

Abstract: A large-scale phylogenetic study is presented for Cucujoidea (Coleoptera), a diverse superfamily of beetles that historically has been taxonomically difficult. This study is the most comprehensive analysis of cucujoid taxa to date, with DNA sequence data sampled from eight genes (four nuclear, four mitochondrial) for 384 coleopteran taxa, including exemplars of 35 (of 37) families and 289 genera of Cucujoidea. Maximum-likelihood analyses of these data present many significant relationships, some proposed previously and some novel. Tenebrionoidea and Lymexyloidea are recovered together and Cleroidea forms the sister group to this clade. Chrysomeloidea and Curculionoidea are recovered as sister taxa and this clade (Phytophaga) forms the sister group to the core Cucujoidea (Cucujoidea s.n.). The nitidulid series is recovered as the earliest-diverging core cucujoid lineage, although the earliest divergences among core Cucujoidea are only weakly supported. The cerylonid series (CS) is recovered as monophyletic and is supported as a major Cucujiform clade, sister group to the remaining superfamilies of Cucujiformia. Currently recognized taxa that were not recovered as monophyletic include Cucujoidea, Endomychidae, Cerylonidae and Bothrideridae. Biphyllidae and Byturidae were recovered in Cleroidea. The remaining Cucujoidea were recovered in two disparate major clades: one comprising the nitidulid series + erotylid series + Boganiidae and Hobartiidae + cucujid series, and the other comprising the cerylonid series. Propalticidae are recovered within Laemophloeidae. The cerylonid series includes two major clades, the bothriderid group and the coccinellid group. Akalyptoischiidae are recovered as a separate clade from Latridiidae. Eupsilobiinae are recovered as the sister taxon to Coccinellidae. In light of these findings, many formal changes to cucujiform beetle classification are proposed. Biphyllidae and Byturidae are transferred to Cleroidea. The cerylonid series is formally recognized as a new superfamily, Coccinelloidea stat.n. Current subfamilies elevated (or re-elevated) to family status include: Murmidiidae stat.n., Teredidae stat.n., Euxestidae stat.n., Anamorphidae stat.rev., Eupsilobiidae stat.n., and Mycetaeidae stat.n. The following taxa are redefined and characterized: Cleroidea s.n., Cucujoidea s.n., Cerylonidae s.n., Bothrideridae s.n., Endomychidae s.n. A new subfamily, Cyclotominae stat.n., is described. Stenotarsinae syn.n. is formally subsumed within a new concept of Endomychinae s.n.