2,819 research outputs found
Bernardo Alberto Houssay (1887 -1971)
His early years, his family. The parents of Bernardo Alberto, Alberto Houssay and Clara Laffont, were born in the South of France, the former in Bayonne and the latter in Aussanes- Angles (Hautes Pyrenees). They married in Argentina and a daughter was born. Soon after, they returned to France as Alberto Houssay's baccalaureate obtained in France was not recognized in Argentina. In Bordeaux, Alberto Houssay graduated as a lawyer and Doctor in Law. There two sons were born.OriginalFil: Foglia, Virgilio G.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinapapelScan Tailor advKofax Power v.3.1Fujitsu Scan Snap 600Biografia BAHUnidad documental simpleBiblioteca Bernardo A. Houssay-0
Facing Non-Stationary Conditions with a New Indicator of Entropy Increase: The Cassandra Algorithm
We address the problem of detecting non-stationary effects in time series (in
particular fractal time series) by means of the Diffusion Entropy Method (DEM).
This means that the experimental sequence under study, of size , is explored
with a window of size . The DEM makes a wise use of the statistical
information available and, consequently, in spite of the modest size of the
window used, does succeed in revealing local statistical properties, and it
shows how they change upon moving the windows along the experimental sequence.
The method is expected to work also to predict catastrophic events before their
occurrence.Comment: FRACTAL 2002 (Spain
Los caracteres biocenóticos de las lagunas basálticas del oeste de Neuquén
Fil: Roig, Virgilio G..
Universidad Nacional de Cuyo. Instituto de BiologíaFil: Cei, José M..
Universidad Nacional de Cuyo. Instituto de Biologí
Rotational sensitivity of the "G-Pisa" gyrolaser
G-Pisa is an experiment investigating the possibility to operate a high
sensitivity laser gyroscope with area less than for improving the
performances of the mirrors suspensions of the gravitational wave antenna
Virgo. The experimental set-up consists in a He-Ne ring laser with a 4 mirrors
square cavity. The laser is pumped by an RF discharge where the RF oscillator
includes the laser plasma in order to reach a better stability. The contrast of
the Sagnac fringes is typically above 50% and a stable regime has been reached
with the laser operating both single mode or multimode. The effect of hydrogen
contamination on the laser was also checked. A low-frequency sensitivity, below
, in the range of has been
measured.Comment: 6 pages, 6 figures, presented at the EFTF-IFCS joint conference 200
Spatial variability of switchgrass (Panicum virgatum L.) yield as related to soil parameters in a small field
The harvested biomass of switchgrass (Panicum virgatum L.) is generally much lower than its potential; this may be due to several factors including not recovering all the biomass at harvest, weed competition, pests, disease and spatial variation of soil features. The objective of this research was to quantify the yield spatial variation of switchgrass and relate it to soil parameters, in a field of about 5 ha, in 2004 and 2005. Several thematic maps of soil parameters and biomass yield were produced using GIS and geostatistical methods. Soil parameters changed consistently within very short distances and biomass yield varied from 3 to more than 20 Mg ha(-1). This remarkable variation indicates that the potential for increasing switchgrass productivity is a real prospect. Furthermore, spatial variation of yield showed similar patterns in the 2 years (r = 0.38**), and therefore a major influence of site characteristics on switchgrass yield can be assumed to occur. Significant correlations were found between biomass yield and soil N, P, moisture and pH as well as between soil parameters. Some soil parameters such as sand content showed patchy spatial distribution. Conversely, a reliable spatial dependence could not be identified for other parameters such as P. Further research is needed
Compression and diffusion: a joint approach to detect complexity
The adoption of the Kolmogorov-Sinai (KS) entropy is becoming a popular
research tool among physicists, especially when applied to a dynamical system
fitting the conditions of validity of the Pesin theorem. The study of time
series that are a manifestation of system dynamics whose rules are either
unknown or too complex for a mathematical treatment, is still a challenge since
the KS entropy is not computable, in general, in that case. Here we present a
plan of action based on the joint action of two procedures, both related to the
KS entropy, but compatible with computer implementation through fast and
efficient programs. The former procedure, called Compression Algorithm
Sensitive To Regularity (CASToRe), establishes the amount of order by the
numerical evaluation of algorithmic compressibility. The latter, called Complex
Analysis of Sequences via Scaling AND Randomness Assessment (CASSANDRA),
establishes the complexity degree through the numerical evaluation of the
strength of an anomalous effect. This is the departure, of the diffusion
process generated by the observed fluctuations, from ordinary Brownian motion.
The CASSANDRA algorithm shares with CASToRe a connection with the Kolmogorov
complexity. This makes both algorithms especially suitable to study the
transition from dynamics to thermodynamics, and the case of non-stationary time
series as well. The benefit of the joint action of these two methods is proven
by the analysis of artificial sequences with the same main properties as the
real time series to which the joint use of these two methods will be applied in
future research work.Comment: 27 pages, 9 figure
The glucose necessary to maintain the glucemia in eviscerated dogs
The study of carbohydrate changes in eviscerated animals as a method for investigating the glucose utilization in the peripheral tissues has been carried out by Soskin (1, 2) on the dog, by Mirsky and Broh-Kahn (3) on the rabbit, and by Russell (4) on the rat. We have carried out a large number of experiments in dogs in order to evaluate this method and to compare the results obtained in normal dogs with those obtained in hypophysectomized, diabetic and thyroidtreated dogs.Fil: Houssay, Bernardo Alberto. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Dosne, Christiane. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Foglia, Virgilio G.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinapapelKofax Power v.3.1Fujitsu ScanSnap SV600Trabajos IBYMEUnidad documental simpleBiblioteca Bernardo A. Houssay-0
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