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Institution

University of Memphis

EducationMemphis, Tennessee, United States
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.


Papers
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Journal ArticleDOI
28 Apr 1988-Nature
TL;DR: It is reported here that the reproductive behaviour and endocrine physiology of an adult is influenced by the temperature experienced as an embryo, and the perception of a female to courtship by a male is influence by incubation temperature.
Abstract: Gonadal differentiation in amniote vertebrates is controlled by one of two mechanisms: genotypic sex determination (GSD) or environmental sex determination (ESD)1. After differentiation the fetal gonad produces sex steroid hormones which govern the development of other components of sexuality2,3. Thus, the primary sex determiner is thought to operate solely as a trigger that initiates a cascade of events culminating in adult sex differences. In the leopard gecko (Eublephans macularius), gonadal and morphological sex is determined by incubation temperature, with relatively 'hot' temperatures (32 °C) resulting in mostly male offspring and relatively 'cold' temperatures (26 °C) resulting in only female offspring4,5. We report here that the reproductive behaviour and endocrine physiology of an adult is influenced by the temperature experienced as an embryo. Also, the perception of a female to courtship by a male is influenced by incubation temperature. These data indicate that incubation temperature, the primary determiner of sex in this species, has differential effects on adult sexuality.

145 citations

Journal ArticleDOI
TL;DR: In this article, the authors present an integrated investigation into the factors affecting executive ownership, the market value of the firm, and executive compensation by explicitly incorporating the simultaneity of the process determining these variables into the empirical estimation.
Abstract: This study presents an integrated investigation into the factors affecting executive ownership, the market value of the firm, and executive compensation by explicitly incorporating the simultaneity of the process determining these variables into the empirical estimation. Overall, the results of the study support the notion that a firm's market value, executive stock ownership, and executive compensation are jointly determined. Further, the findings suggest that executive stock ownership and executive compensation may serve as a type of bond by which top executives are induced to act in the best interests of shareholders. The study also finds that a firm's q ratio and an executive's job-specific experience (as well as firm size) are important determinants of executive compensation. This result is generally consistent with the view that the firm optimally establishes its managerial compensation plan in response to both its operating environment and the specific personal characteristics of its chief executive(s).

145 citations

Journal ArticleDOI
TL;DR: This work investigates the effectiveness of fusing two novel texture features along with intensity in multimodal magnetic resonance (MR) images for pediatric brain tumor segmentation and classification and suggests that the fusion of fractal, fractalwavelet and intensity features in multi-modality MR images offers better tumor segmentsation results when compared to that of just fractal andintensity features in single modality MR pictures.

145 citations

Journal ArticleDOI
TL;DR: The phylogeny of Staphyliniformia is reconstructed using DNA sequences from nuclear 28S rDNA and the nuclear protein‐coding gene CAD for 282 species representing all living families and most subfamilies, with a representative sample of Scarabaeiformia serving as a near outgroup, and three additional beetles as more distant outgroups.
Abstract: The beetle series Staphyliniformia exhibits extraordinary taxonomic, ecological and morphological diversity. To gain further insight into staphyliniform relationships and evolution, we reconstructed the phylogeny of Staphyliniformia using DNA sequences from nuclear 28S rDNA and the nuclear protein-coding gene CAD for 282 species representing all living families and most subfamilies, a representative sample of Scarabaeiformia serving as a near outgroup, and three additional beetles as more distant outgroups. Under both Bayesian inference (BI) and maximum likelihood inference (MLI), the major taxa within Staphyliniformia are each monophyletic: (i) Staphylinoidea, (ii) Hydrophiloidea s.l., and the contained superfamilies (iii) Hydrophiloidea s.s. and (iv) Histeroidea, although Staphylinoidea and Hydrophiloidea s.l. are not strongly supported by MLI bootstrap. Scarabaeiformia is monophyletic under both methods of phylogenetic inference. However, the relative relationships of Staphylinoidea, Hydrophiloidea s.l. and Scarabaeiformia differ between BI and MLI: under BI, Staphyliniformia and Scarabaeiformia were sister groups; under MLI, Hydrophiloidea s.l. and Scarabaeiformia were sister groups and these together were sister to Staphylinoidea. The internal relationships in Scarabaeiformia were similar under both methods of phylogenetic inference, with Cetoniinae, Dynastinae + Rutelinae, Hybosoridae, Passalidae, Scarabaeidae and Scarabaeinae recovered as monophyla. Histeridae comprised two major clades: (1) Abraeinae, Trypanaeine and Trypeticinae; and (2) Chlamydopsinae, Dendrophilinae, Haeteriinae, Histerinae, Onthophilinae, Saprininae and Tribalinae. The relationships among early-divergent Hydrophiloidea differed between BI and MLI, and overall were unresolved or received only moderate to low nodal support. The staphylinoid families Agyrtidae, Hydraenidae and Ptiliidae were recovered as monophyletic; the latter two were sister taxa, and Staphylinidae + Silphidae was also monophyletic. Silphidae was placed within Staphylinidae in close relation to a subset of Tachyporinae. Pselaphinae and Scydmaeninae were both recovered within Staphylinidae, in accordance with recent analyses of morphological characters, although not always with recently proposed sister taxa. None of the four major groups of Staphylinidae proposed by Lawrence and Newton (1982) was recovered as monophyletic. Certain highly specialized staphyliniform habits and morphologies, such as abdominal defensive glands and reduced elytra, have arisen in parallel in separate lineages. Further, our analyses support two major transitions to an aquatic lifestyle within Staphyliniformia: once within Staphylinoidea (Hydraenidae), and once within Hydrophiloidea s.l. (Hydrophiloidea s.s.). On a smaller scale, the most common transition is from litter to subcortical or to periaquatic microhabitats and the next most common is from litter to carrion and to fungi. Overall, transitions to periaquatic microhabitats were the most numerous. The broad picture in Staphyliniformia seems to be a high level of evolutionary plasticity, with multiple possible pathways to and from many microhabitat associations, and litter as a major source microhabitat for diversification. In Scarabaeiformia, the most common transitions were from litter to foliage, with flowers to litter, litter to flowers, and litter to dung being next, and then litter to roots, logs or carrion. Litter is again the largest overall source microhabitat. The most common transitions were to foliage and flowers. It thus seems that the litter environment presents ecological and evolutionary opportunities/challenges that facilitate entry of Staphyliniformia and Scarabaeiformia into ‘new’ and different ecological adaptive zones.

145 citations

Journal ArticleDOI
TL;DR: Drawing on literature from strategic management, industrial organization economics, and organization theory, a framework is developed which suggests that regulatory scope and regulatory incrementalism influence strategic choice and performance in the U.S. banking industry.
Abstract: This study explores the effects of regulation and deregulation on strategic choice and performance in the US banking industry Drawing on literature from strategic management, industrial organization economics, and organization theory, we develop a framework which suggests that regulatory scope and regulatory incrementalism influence strategic choice and performance A path analytic model is used to empirically examine these influences The results suggest that deregulation has direct effects on firms' strategic choices and both direct and indirect effects on risk and return

145 citations


Authors

Showing all 7827 results

NameH-indexPapersCitations
James F. Sallis169825144836
Robert G. Webster15884390776
Ching-Hon Pui14580572146
James Whelan12878689180
Tom Baranowski10348536327
Peter C. Doherty10151640162
Jian Chen96171852917
Arthur C. Graesser9561438549
David Richards9557847107
Jianhong Wu9372636427
Richard W. Compans9152631576
Shiriki K. Kumanyika9034944959
Alexander J. Blake89113335746
Marek Czosnyka8874729117
David M. Murray8630021500
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
202327
2022169
20211,049
20201,044
2019843
2018846