Variables sintomáticas en las estimaciones poblacionales a nivel cantonal en Costa Rica

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La dinámica de la pobreza y las variables de población en la Argentina: un analisis longitudinal a partir de la encuesta permanente de hogares (1995-2003)

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Ajuste de proyecciones de poblaciones menores con variables sintomáticas: el caso del Gran Córdoba (Argentina), 2001-2016

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Insect/Bt-cotton interactions: Are immunological variables and hemocyte ultrastructure in Podisus nigrispinus (Hemiptera: Pentatomidae) affected?

Recent studies have shown that ingestion by the army worm Spodoptera frugiperda of Cry1Ac toxin from Bt cotton promotes histochemical and ultrastructural changes in the digestive cells of the predatory pentatomid bug Podisus nigrispinus. Therefore, mindful of the changes in the midgut of the predator, which represents the first line of defence in this insect, our aim was to test the hypothesis that the consumption of Bt cotton-fed S. frugiperda by P. nigrispinus might lead to alterations in components of the immune system of P. nigrispinus. The Cry1Ac toxin level in the leaves of Bt cotton, nitric oxide, phenoloxidase activity, and total proteins were quantified by ELISA. Total and differential hemocyte counts were evaluated, and hemocyte ultrastructure analysis was undertaken. We found that ingestion of the prey fed daily with approximately 23 ± 0.70 ng g-1 Cry1Ac by wet weight of leaves, and expressed by the Bt cotton, induces small ultrastructural changes in the predator's granulocytes and plasmatocytes. However, these changes did not affect the total number and differential and humoral variables analyzed for the bug's hemocytes. © 2013 Copyright Taylor and Francis Group, LLC.

A meta-analytical study about the relation of blood plasma addition in diets for piglets in the post-weaning and productive performance variables

The meta-analysis was used to evaluate the performance of piglets in post-weaning period, without imposition of sanitary challenge and fed diets containing blood plasma, obtained by spray-dried process (SDBP). Piglets are faced with normal challenges in post-weaning period such as environmental stress and the substitution of the liquid diet to a solid one. References regarding sanitary challenges were disregarded in this study. Only data regarding normal and expected challenges were considered. Data were obtained from indexed journals with information extracted from the material, methods and results sections of pre-selected scientific articles. First, the database was analyzed graphically to observe the distribution of data and presence of outliers. Afterwards correlation analysis and variance-covariance analyses were carried out. The database contained a total of 23 articles. The average initial weight of the piglets was 8.02. kg (4.00-9.28. kg) and the average initial age was 27 days (14-32 days). The average duration of feeding diets containing spray-dried blood plasma (SDBP) was 9 days (6-28 days). SDBP increased the feed conversion by 20.2% (P<0.05) during the initial period. Feed conversion during the total period was 10.2% higher (P<0.05) for animals fed with SDBP. Average daily weight gain and daily feed intake were not affected (P>0.05) during the entire period, but average daily gain was higher (P<0.05) for animals fed with SDBP during the initial period. The initial age of supplementation influenced the average daily weight gain and average daily feed intake of animals fed with SDBP. Better results were obtained than those obtained for animals up to 35 days of age fed diets without added SDBP supplementation. In early post-weaning period for piglets weaned up to 35 days of age, the SDBP supplementation positively influenced the average daily weight gain and feed conversion. © 2013 Elsevier B.V.

Inclusive search for supersymmetry using razor variables in pp collisions at √s=7 TeV

An inclusive search is presented for new heavy particle pairs produced in √s=7 TeV proton-proton collisions at the LHC using 4.7±0.1 fb -1 of integrated luminosity. The selected events are analyzed in the 2D razor space of MR, an event-by-event indicator of the heavy particle mass scale, and R, a dimensionless variable related to the missing transverse energy. The third-generation sector is probed using the event heavy-flavor content. The search is sensitive to generic supersymmetry models with minimal assumptions about the superpartner decay chains. No excess is observed in the number of events beyond that predicted by the standard model. Exclusion limits are derived in the CMSSM framework as well as for simplified models. Within the CMSSM parameter space considered, gluino masses up to 800 GeV and squark masses up to 1.35 TeV are excluded at 95% confidence level depending on the model parameters. The direct production of pairs of top or bottom squarks is excluded for masses as high as 400 GeV. © 2013 CERN.

Search for supersymmetry in hadronic final states with missing transverse energy using the variables αT and b-quark multiplicity in pp collisions at {Mathematical expression}

An inclusive search for supersymmetric processes that produce final states with jets and missing transverse energy is performed in pp collisions at a centre-of-mass energy of 8 TeV. The data sample corresponds to an integrated luminosity of 11.7 fb-1 collected by the CMS experiment at the LHC. In this search, a dimensionless kinematic variable, αT, is used to discriminate between events with genuine and misreconstructed missing transverse energy. The search is based on an examination of the number of reconstructed jets per event, the scalar sum of transverse energies of these jets, and the number of these jets identified as originating from bottom quarks. No significant excess of events over the standard model expectation is found. Exclusion limits are set in the parameter space of simplified models, with a special emphasis on both compressed-spectrum scenarios and direct or gluino-induced production of third-generation squarks. For the case of gluino-mediated squark production, gluino masses up to 950-1125 GeV are excluded depending on the assumed model. For the direct pair-production of squarks, masses up to 450 GeV are excluded for a single light first- or second-generation squark, increasing to 600 GeV for bottom squarks. © 2013 CERN for the benefit of the CMS collaboration.

Poincaré plot indexes of heart rate variability: Relationships with other nonlinear variables

The Poincaré plot for heart rate variability analysis is a technique considered geometrical and non-linear, that can be used to assess the dynamics of heart rate variability by a representation of the values of each pair of R-R intervals into a simplified phase space that describes the system's evolution. The aim of the present study was to verify if there is some correlation between SD1, SD2 and SD1/SD2 ratio and heart rate variability nonlinear indexes either in disease or healthy conditions. 114 patients with arterial coronary disease and 65 healthy subjects underwent 30. minute heart rate registration, in supine position and the analyzed indexes were as follows: SD1, SD2, SD1/SD2, Sample Entropy, Lyapunov Exponent, Hurst Exponent, Correlation Dimension, Detrended Fluctuation Analysis, SDNN, RMSSD, LF, HF and LF/HF ratio. Correlation coefficients between SD1, SD2 and SD1/SD2 indexes and the other variables were tested by the Spearman rank correlation test and a regression analysis. We verified high correlation between SD1/SD2 index and HE and DFA (α1) in both groups, suggesting that this ratio can be used as a surrogate variable. © 2013 Elsevier B.V.

Un modelo de interrelaciones entre variables económicas y demográficas

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Propension a lo urbano, estructura familiar y variables intermedias de la fecundidad en sectores rurales de America Latina

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Metodo para determinar la influencia relativa de ciertas variables en un nivel de fecundidad

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