134 research outputs found
Fluctuations of company yearly profits versus scaled revenue: Fat tail distribution of Levy type
We analyze annual revenues and earnings data for the 500 largest-revenue U.S.
companies during the period 1954-2007. We find that mean year profits are
proportional to mean year revenues, exception made for few anomalous years,
from which we postulate a linear relation between company expected mean profit
and revenue. Mean annual revenues are used to scale both company profits and
revenues. Annual profit fluctuations are obtained as difference between actual
annual profit and its expected mean value, scaled by a power of the revenue to
get a stationary behavior as a function of revenue. We find that profit
fluctuations are broadly distributed having approximate power-law tails with a
Levy-type exponent , from which we derive the associated
break-even probability distribution. The predictions are compared with
empirical data.Comment: 6 pages, 6 figure
Empoderamiento y feminismo comunitario en la conservaciĂłn del maĂz en MĂ©xico
Articulo cientĂfico para revista indizada.El objetivo es analizar, desde una perspectiva basada en el feminismo comunitario, el proceso de empoderamiento de las mujeres que conforman un grupo de ocho integrantes matlatzincas de la comunidad de San Francisco Oxtotilpan, MĂ©xico, a travĂ©s de prĂĄcticas productivas, alimentarias y culturales en torno al maĂz nativo. Los datos fueron recogidos durante 2014 y 2015 con tĂ©cnicas etnogrĂĄficas que incluyen: observaciĂłn participante, historias de vida, grupos focales, entrevistas semiestructuradas y a profundidad. Son mujeres que muestran cinco dimensiones de poder (social, corporal, material, simbĂłlico y cognitivo) que repercuten en la preservaciĂłn del maĂz nativo, al generar la masa crĂtica necesaria para incorporar a otras mujeres en acciones favorables para la soberanĂa alimentaria
Glycine propionyl-L-carnitine produces enhanced anaerobic work capacity with reduced lactate accumulation in resistance trained males
Glucose-6-Phosphate Dehydrogenase Protects Escherichia coli from Tellurite-Mediated Oxidative Stress
The tellurium oxyanion tellurite induces oxidative stress in most microorganisms. In Escherichia coli, tellurite exposure results in high levels of oxidized proteins and membrane lipid peroxides, inactivation of oxidation-sensitive enzymes and reduced glutathione content. In this work, we show that tellurite-exposed E. coli exhibits transcriptional activation of the zwf gene, encoding glucose 6-phosphate dehydrogenase (G6PDH), which in turn results in augmented synthesis of reduced nicotinamide adenine dinucleotide phosphate (NADPH). Increased zwf transcription under tellurite stress results mainly from reactive oxygen species (ROS) generation and not from a depletion of cellular glutathione. In addition, the observed increase of G6PDH activity was paralleled by accumulation of glucose-6-phosphate (G6P), suggesting a metabolic flux shift toward the pentose phosphate shunt. Upon zwf overexpression, bacterial cells also show increased levels of antioxidant molecules (NADPH, GSH), better-protected oxidation-sensitive enzymes and decreased amounts of oxidized proteins and membrane lipids. These results suggest that by increasing NADPH content, G6PDH plays an important role in E. coli survival under tellurite stress
Neuroprotection by acetoacetate and ÎČ-hydroxybutyrate against NMDA-induced RGC damage in ratâpossible involvement of kynurenic acid
Atlas of marine bony fish otoliths (Sagittae) of Southeastern - Southern Brazil Part I: Gadiformes (Macrouridae, Moridae, Bregmacerotidae, Phycidae and Merlucciidae); Part II: Perciformes (Carangidae, Sciaenidae, Scombridae and Serranidae)
A suplementação de L-carnitina nĂŁo promove alteraçÔes na taxa metabĂłlica de repouso e na utilização dos substratos energĂ©ticos em indivĂduos ativos
Bidirectional fluxes of spermine across the mitochondrial membrane.
The polyamine spermine is transported into the
mitochondrial matrix by an electrophoretic mechanism
having as driving force the negative electrical membrane
potential (DW). The presence of phosphate increases
spermine uptake by reducingDpH and enhancingDW. The
transport system is a specific uniporter constituted by a
protein channel exhibiting two asymmetric energy barriers
with the spermine binding site located in the energy well
between the two barriers. Although spermine transport is
electrophoretic in origin, its accumulation does not follow
the Nernst equation for the presence of an efflux pathway.
Spermine efflux may be induced by different agents, such as
FCCP, antimycin A and mersalyl, able to completely or
partially reduce theDWvalue and, consequently, suppress
or weaken the force necessary to maintain spermine in the
matrix. However this efflux may also take place in normal
conditions when the electrophoretic accumulation of the
polycationic polyamine induces a sufficient drop inDWable
to trigger the efflux pathway. The release of the polyamine
is most probably electroneutral in origin and can take place
in exchange with protons or in symport with phosphate
anion. The activity of both the uptake and efflux pathways
induces a continuous cycling of spermine across the mitochondrial membrane, the rate of which may be prominent in imposing the concentrations of spermine in the inner and
outer compartment. Thus, this event has a significant role on
mitochondrial permeability transition modulation and consequently on the triggering of intrinsic apoptosis
International nosocomial infection control consortium (INICC) report, data summary of 36 countries, for 2004-2009
The results of a surveillance study conducted by the International Nosocomial Infection Control Consortium (INICC) from January 2004 through December 2009 in 422 intensive care units (ICUs) of 36 countries in Latin America, Asia, Africa, and Europe are reported. During the 6-year study period, using Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN; formerly the National Nosocomial Infection Surveillance system [NNIS]) definitions for device-associated health care-associated infections, we gathered prospective data from 313,008 patients hospitalized in the consortium's ICUs for an aggregate of 2,194,897 ICU bed-days. Despite the fact that the use of devices in the developing countries' ICUs was remarkably similar to that reported in US ICUs in the CDC's NHSN, rates of device-associated nosocomial infection were significantly higher in the ICUs of the INICC hospitals; the pooled rate of central line-associated bloodstream infection in the INICC ICUs of 6.8 per 1,000 central line-days was more than 3-fold higher than the 2.0 per 1,000 central line-days reported in comparable US ICUs. The overall rate of ventilator-associated pneumonia also was far higher (15.8 vs 3.3 per 1,000 ventilator-days), as was the rate of catheter-associated urinary tract infection (6.3 vs. 3.3 per 1,000 catheter-days). Notably, the frequencies of resistance of Pseudomonas aeruginosa isolates to imipenem (47.2% vs 23.0%), Klebsiella pneumoniae isolates to ceftazidime (76.3% vs 27.1%), Escherichia coli isolates to ceftazidime (66.7% vs 8.1%), Staphylococcus aureus isolates to methicillin (84.4% vs 56.8%), were also higher in the consortium's ICUs, and the crude unadjusted excess mortalities of device-related infections ranged from 7.3% (for catheter-associated urinary tract infection) to 15.2% (for ventilator-associated pneumonia). Copyright © 2012 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved
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