Esbozo de marco conceptual para el estudio del cambio en las organizaciones universitarias, con especial consideración del caso argentino

El objetivo del trabajo es ofrecer un conjunto de herramientas teóricas para el análisis del cambio en los SES, con especial consideración del caso de las universidades argentinas. La perspectiva que lo anima es el producto de la combinación de elementos de la teoría organizacional -tanto en sus versiones generales como en particular las referidas y pensadas para el estudio de las organizaciones universitarias- con el espíritu del análisis estratégico. Si el análisis estratégico supone actores racionales en busca de la maximización de su propio beneficio o interés, la teoría organizacional, al menos en las versiones que se recogen aquí, permite dar cuenta de la identidad de esos actores y, consecuentemente, del proceso de conformación de los intereses que aquél asume como supuestos. Además de su función en la explicación de la identidad de los actores, los elementos de la teoría organizacional que aquí se rescatan permiten ordenar y comprender el escenario en que ellos intervienen

Esbozo de marco conceptual para el estudio del cambio en las organizaciones universitarias, con especial consideración del caso argentino

El objetivo del trabajo es ofrecer un conjunto de herramientas teóricas para el análisis del cambio en los SES, con especial consideración del caso de las universidades argentinas. La perspectiva que lo anima es el producto de la combinación de elementos de la teoría organizacional -tanto en sus versiones generales como en particular las referidas y pensadas para el estudio de las organizaciones universitarias- con el espíritu del análisis estratégico. Si el análisis estratégico supone actores racionales en busca de la maximización de su propio beneficio o interés, la teoría organizacional, al menos en las versiones que se recogen aquí, permite dar cuenta de la identidad de esos actores y, consecuentemente, del proceso de conformación de los intereses que aquél asume como supuestos. Además de su función en la explicación de la identidad de los actores, los elementos de la teoría organizacional que aquí se rescatan permiten ordenar y comprender el escenario en que ellos intervienen

Esbozo de marco conceptual para el estudio del cambio en las organizaciones universitarias, con especial consideración del caso argentino

El objetivo del trabajo es ofrecer un conjunto de herramientas teóricas para el análisis del cambio en los SES, con especial consideración del caso de las universidades argentinas. La perspectiva que lo anima es el producto de la combinación de elementos de la teoría organizacional -tanto en sus versiones generales como en particular las referidas y pensadas para el estudio de las organizaciones universitarias- con el espíritu del análisis estratégico. Si el análisis estratégico supone actores racionales en busca de la maximización de su propio beneficio o interés, la teoría organizacional, al menos en las versiones que se recogen aquí, permite dar cuenta de la identidad de esos actores y, consecuentemente, del proceso de conformación de los intereses que aquél asume como supuestos. Además de su función en la explicación de la identidad de los actores, los elementos de la teoría organizacional que aquí se rescatan permiten ordenar y comprender el escenario en que ellos intervienen

Upper limit on the cosmic-ray photon flux above 10(19) eV using the surface detector of the Pierre Auger Observatory

A method is developed to search for air showers initiated by photons using data recorded by the surface detector of the Auger Observatory. The approach is based on observables sensitive to the longitudinal shower development, the signal risetime and the curvature of the shower front. Applying this method to the data, tipper limits on the flux of photons of 3.8 x 10(-3), 2.5 x 10(-3), and 2.2 x 10(-3) km(-2) sr(-1) yr(-1) above 10(19) eV, 2 x 10(19) eV, and 4 x 10(19) eV are derived, with corresponding limits on the fraction of photons being 2.0%, 5.1%, and 31% (all limits at 95% c.l.). These photon limits disfavor certain exotic models of sources of cosmic rays. The results also show that the approach adopted by the Auger Observatory to calibrate the shower energy is not strongly biased by a contamination from photons. (C) 2008 Elsevier B.V. All rights reserved.

The fluorescence detector of the Pierre Auger Observatory

The Pierre Auger Observatory is a hybrid detector for ultra-high energy cosmic rays. It combines a surface array to measure secondary particles at ground level together with a fluorescence detector to measure the development of air showers in the atmosphere above the array. The fluorescence detector comprises 24 large telescopes specialized for measuring the nitrogen fluorescence caused by charged particles of cosmic ray air showers. In this paper we describe the components of the fluorescence detector including its optical system, the design of the camera, the electronics, and the systems for relative and absolute calibration. We also discuss the operation and the monitoring of the detector. Finally, we evaluate the detector performance and precision of shower reconstructions. (C) 2010 Elsevier B.V All rights reserved.

Memoir of George Edmund Street, R.A., 1824-1881 /

Includes lectures given before students of the Royal Academy in the spring of 1881.

Cutaneous markers of photo-damage and risk of basal cell carcinoma of the skin : a meta-analysis

BACKGROUND: Epidemiologic research has demonstrated that cutaneous markers of photo-damage are associated with risk of basal cell carcinoma (BCC). However there has been no previous attempt to calculate pooled risk estimates. METHODS: We conducted a systematic review and meta-analysis after extracting relevant studies published up to January 2013 from five electronic databases. Eligible studies were those that permitted quantitative assessment of the association between histologically-confirmed BCC and actinic keratoses, solar elastosis, solar lentigines, or telangiectasia. RESULTS: Seven eligible studies were identified and summary odds ratios (OR) were calculated using both random and quality effects models. Having more than ten actinic keratoses was most strongly associated with BCC, conferring up to a 5-fold increase in risk (OR: 4.97; 95% CI: 3.26, 7.58). Other factors, including solar elastosis, solar lentigines, and telangiectasia had weaker but positive associations with BCC with ORs around 1.5. CONCLUSIONS: Markers of chronic photo-damage are positively associated with BCC. The presence of actinic keratoses was the most strongly associated with BCC of the markers examined. IMPACT: This work highlights the relatively modest association between markers of chronic ultraviolet exposure and BCC.

Loss of epithelial markers and acquisition of vimentin expression in adriamycin- and vinblastine-resistant human breast cancer cell lines

We have previously observed that breast cancer cell lines could exhibit either epithelial or fibroblastic phenotypes as reflected by their morphologies and intermediate filament protein expression (C. L. Sommers, D. Walker-Jones, S. E. Heckford, P. Worland, E. Valverius, R. Clark, M. Stampfer, and E. P. Gelmann, Cancer Res., 49: 4258-4263, 1989). Fibroblastoid, vimentin-expressing breast cancer cell lines are more invasive in vitro and in vivo (E. W. Thompson, S. Paik, N. Brunner, C. L. Sommers, G. Zugmaier, R. Clarke, T. B. Shima, J. Torri, S. Donahue, M. E. Lippman, G. R. Martin, and R. B. Dickson, J. Cell. Physiol., 150: 534-544, 1992). We hypothesized that a breast cancer cell with an epithelial phenotype could undergo a transition to a fibroblastic phenotype, possibly resulting in more invasive capacity. We now show that two Adriamycin-resistant MCF-7 cell lines and a vinblastine-resistant ZR-75-B cell line have undergone such a transition. Adriamycin-resistant MCF-7 cells express vimentin, have diminished keratin 19 expression, have lost cell adhesion molecule uvomorulin expression, and have reduced formation of desmosomes and tight junctions as determined by reduced immunodetection of their components desmoplakins I and II and zonula occludens (ZO)-1. Other MCF-7 cell lines selected for resistance to vinblastine and to Adriamycin and verapamil did not have these characteristics, indicating that drug selection does not invariably cause these phenotypic changes. In addition, to determine if vimentin expression in MCF-7 cells alone could manifest a fibroblastic phenotype, we transfected the full-length human vimentin complementary DNA into MCF-7 cells. Although vimentin expression was achieved in MCF-7 cells, it did not affect the phenotype of the cells in terms of the distribution of keratins, desmoplakins I and II, ZO-1, or uvomorulin or in terms of in vitro invasiveness. We conclude that vimentin expression is a marker for a fibroblastic and invasive phenotype in breast cancer cells but does not by itself give rise to this phenotype.

The validity of the GENEActiv wrist-worn accelerometer for measuring adult sedentary time in free living

OBJECTIVES Based on self-reported measures, sedentary time has been associated with chronic disease and mortality. This study examined the validity of the wrist-worn GENEactiv accelerometer for measuring sedentary time (i.e. sitting and lying) by posture classification, during waking hours in free living adults. DESIGN Fifty-seven participants (age=18-55 years 52% male) were recruited using convenience sampling from a large metropolitan Australian university. METHODS Participants wore a GENEActiv accelerometer on their non-dominant wrist and an activPAL device attached to their right thigh for 24-h (00:00 to 23:59:59). Pearson's Correlation Coefficient was used to examine the convergent validity of the GENEActiv and the activPAL for estimating total sedentary time during waking hours. Agreement was illustrated using Bland and Altman plots, and intra-individual agreement for posture was assessed with the Kappa statistic. RESULTS Estimates of average total sedentary time over 24-h were 623 (SD 103) min/day from the GENEActiv, and 626 (SD 123) min/day from the activPAL, with an Intraclass Correlation Coefficient of 0.80 (95% confidence intervals 0.68-0.88). Bland and Altman plots showed slight underestimation of mean total sedentary time for GENEActiv relative to activPAL (mean difference: -3.44min/day), with moderate limits of agreement (-144 to 137min/day). Mean Kappa for posture was 0.53 (SD 0.12), indicating moderate agreement for this sample at the individual level. CONCLUSIONS The estimation of sedentary time by posture classification of the wrist-worn GENEActiv accelerometer was comparable to the activPAL. The GENEActiv may provide an alternative, easy to wear device based measure for descriptive estimates of sedentary time in population samples