3,290 research outputs found

    Mergers

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    Using small matched samples of companies which are, and are not, highly involved in acquisition in the period 1986-90, an investigation is mounted to ascertain whether "acquisitiveness" has any impact upon the remuneration of the top directors over and above what one would expect because of the growth in "size". The evidence suggests it does, if returns to share options are included in the measure of remuneration.

    Study of the Anatomy of the Alimentary Canal of Brochymena quadripustulata (Hemiptera:Pentatomidae)

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    An anatomical study of the alimentary canal and associated salivary apparatus was conducted for the pentatomid, Brochymena quadripustulata. The esophagus, ventriculus, pylorus, rectum, principal salivary glands and ducts are described and illustrated. Described structures of Brochymena quadripustulata are compared with various species of pentatomids and other hemipterans

    ERK Activation Requires CaM Kinases in MCF-7 Breast Cancer Cells

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    Abstract A key signaling pathway involved in regulating cell growth and proliferation throughout the body is the ERK signaling pathway. ERK is activated via numerous pathways including intracellular calcium release downstream of G-Protein Coupled Receptors (GPCRs). Carbachol, a GPCR-agonist, both increases intracellular calcium and ERK activation in MCF-7 cells. ERK activation and control of cell growth may act through the transcription factor Elk-1. Our goal was to elucidate the specific proteins and kinases upstream of ERK in MCF-7 cells treated with carbachol. Secondly, we wanted to investigate the potential involvement of Elk-1 downstream of ERK. Carbachol treatment of MCF-7 cells triggered ERK and Elk-1 phosphorylation within 5 minutes. Interestingly, transfection of cells with shRNAs directed to either CaM KKα or CaM KIγ significantly inhibited carbachol activation of ERK. Phosphorylation of Elk-1, following carbachol stimulation, was also blocked in siERK2 transfected cells, suggesting that ERK2 is required for carbachol\u27s activation of Elk-1. Our results suggest that carbachol treatment of MCF-7 cells activates ERK and cell growth through CaM KK, CaMKI, and an Elk-1-dependent pathway

    Missing baryons and the soft X-ray background

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    The X-ray background intensity around Lick count galaxies and rich clusters of galaxies is investigated in three ROSAT energy bands. It is found that the X-ray enhancements surrounding concentrations of galaxies exhibit significantly softer spectrum than the standard cluster emission and the average extragalactic background. The diffuse soft emission accompanying the galaxies is consistent with the thermal emission of the hot gas postulated first by the Cen & Ostriker hydrodynamic simulations. Our estimates of the gas temperature - although subject to large uncertainties - averaged over several Mpc scales are below 1 keV, which is substantially below the temperature of the intra-cluster gas, but consistent with temperatures predicted for the local intergalactic medium. It is pointed out that the planned ROSITA mission would be essential for our understanding of the diffuse thermal component of the background.Comment: AA accepted, 6 pages, incl. 4 figure

    A development of logistics management models for the Space Transportation System

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    A new analytic queueing approach was described which relates stockage levels, repair level decisions, and the project network schedule of prelaunch operations directly to the probability distribution of the space transportation system launch delay. Finite source population and limited repair capability were additional factors included in this logistics management model developed specifically for STS maintenance requirements. Data presently available to support logistics decisions were based on a comparability study of heavy aircraft components. A two-phase program is recommended by which NASA would implement an integrated data collection system, assemble logistics data from previous STS flights, revise extant logistics planning and resource requirement parameters using Bayes-Lin techniques, and adjust for uncertainty surrounding logistics systems performance parameters. The implementation of these recommendations can be expected to deliver more cost-effective logistics support

    Small-sample corrections for score tests in Birnbaum-Saunders regressions

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    In this paper we deal with the issue of performing accurate small-sample inference in the Birnbaum-Saunders regression model, which can be useful for modeling lifetime or reliability data. We derive a Bartlett-type correction for the score test and numerically compare the corrected test with the usual score test, the likelihood ratio test and its Bartlett-corrected version. Our simulation results suggest that the corrected test we propose is more reliable than the other tests.Comment: To appear in the Communications in Statistics - Theory and Methods, http://www.informaworld.com/smpp/title~content=t71359723

    Critiquing Quantitative Research Reports: Key Points for the Beginner

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    Nursing research has a long history, beginning with the first nursing researcher--Florence Nightingale. As research continues to evolve, the dissemination of findings is important. Nurses must have have an understanding of how to critically read and appraise research articles in order to assess the value of the findings

    M3-Muscarinic Receptor Activation of ERK and Cell Growth Requires Calcium/Calmodulin-dependent Protein Kinases in MCF-7 Cells

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    Abstract The extracellular signal-regulated protein kinase (ERK) signaling pathway is found in diverse cells throughout the human body. ERK activation has been implicated in breast cancer cell growth and proliferation. Studies have shown that ERK is activated by carbachol, a G Protein-Coupled Receptor (GPCR) agonist, which increases intracellular calcium in MCF-7 cells. The calcium/calmodulin-dependent protein kinase (CaM K) family of proteins including CaM KK, CaM KI, and CaM KII can be activated by increased intracellular calcium. Our goal was to determine whether CaM Ks may be responsible for ERK activation and cell proliferation in carbachol-treated MCF-7 cells and evaluate which GPCR was responsible for these events. Carbachol treatment of MCF-7 cells triggered ERK 1/2 phosphorylation within 5 minutes. Treatment with KN-93, a general CaM Kinase inhibitor and the MEK inhibitor U0126 blocked ERK activation. Carbachol increased MCF-7 cell growth nearly 4-fold, an effect that was also dependent upon CaM Ks and MEK. Interestingly, CaM KK was responsible for ERK activation and cell growth. Pretreatment of MCF-7 cells with 4-DAMP, a selective M3 receptor antagonist, completely blocked carbachol’s activation of ERK and cell growth. Taken together these results suggest that carbachol stimulated ERK phosphorylation and MCF-7 cell growth by the M3 subtype GPCR receptor perhaps through CaM KK

    Luminous superclusters: remnants from inflation

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    We derive the luminosity and multiplicity functions of superclusters compiled for the 2dF Galaxy Redshift Survey, the Sloan Digital Sky Survey (Data Release 4), and for three samples of simulated superclusters. We find for all supercluster samples Density Field (DF) clusters, which represent high-density peaks of the class of Abell clusters, and use median luminosities/masses of richness class 1 DF-clusters to calculate relative luminosity/mass functions. We show that the fraction of very luminous (massive) superclusters in real samples is more than tenfolds greater than in simulated samples. Superclusters are generated by large-scale density perturbations which evolve very slowly. The absence of very luminous superclusters in simulations can be explained either by non-proper treatment of large-scale perturbations, or by some yet unknown processes in the very early Universe.Comment: 6 pages, 3 Figures, submitted for Astronomy and Astrophysic

    Health Promotion in 7 Minutes

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