215 research outputs found

    Comunicación de RSC: una revisión de las tesis clásicas sobre la coherencia entre la acción de RSC y la actividad organizacional

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    La literatura sobre comunicación eficaz de la Responsabilidad Social Corporativa (RSC) es compleja y, en ocasiones, contradictoria respecto al papel de la coherencia entre la actividad de la empresa y las acciones de RSC (fit empresarial clásico). Por una parte, subraya la importancia del fit para una comunicación eficaz. Sin embargo, otros investigadores afirman que el fit podría aumentar el escepticismo y resultar perjudicial. Por último, investigaciones recientes señalan otro tipo de fit: el fit personal, donde lo importante es la coincidencia entre la acción de RSC y los intereses del público. Para intentar esclarecer esta complejidad se llevó a cabo un experimento en el que 86 jóvenes fueron asignados aleatoriamente a tres condiciones experimentales: mensaje de RSC con fit clásico; mensaje de RSC con fit personal y mensaje control. A diferencia de lo que se podría esperar a partir de la literatura previa, no se encontraron diferencias significativas entre los que recibieron el mensaje con fit empresarial y aquellos que recibieron el mensaje control. Por el contrario, aquellos individuos asignados a la condición de fit personal evaluaron a la empresa como más sincera y honesta y manifestaron una intención conductual más favorable hacia ella que los sujetos asignados a la condición de control y que los sujetos asignados a la condición de fit empresarial. El artículo discute la necesidad de replantear el rol del fit clásico empresarial en la comunicación de acciones de RSC y resalta la existencia de otros tipos de fit que pueden ser incluso más determinantes

    Analysis of values and communication of the Responsible Brands. Corporate Brand strategies for sustainability

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    New social demands require responsible behavior of companies. This phenomenon, which has coincided with the development of social responsibility, has a direct impact on the corporate brand and values, including the vision and mission associated with the brand. Using a sample of 10 companies, this study is based on a qualitative analysis study of identity issues related to responsibility and sustainability which are part of the corporate communication message. The results show that brands develop similar discourses in order to exhibit the identity. Only a few of these companies define their strategic positioning on ethical issues.----------------------------------------------------------------------------------------Las nuevas demandas sociales exigen a las empresas un comportamiento responsable. Este fenómeno, que ha coincidido con el desarrollo y auge de la Responsabilidad Social, tiene también un impacto directo en la marca corporativa y en los valores, visión y misión que se asocian a la misma. Con una muestra de 10 empresas, se realiza un estudio cualitativo de los rasgos de identidad vinculados a la responsabilidad y la sostenibilidad presentes en los mensajes de comunicación corporativa. Los resultados muestran que las marcas desarrollan discursos similares para expresar la identidad. Sólo algunas optan por definir su posicionamiento en aspectos éticos

    Prevalence of Bartonella henselae in blood donors and risk of blood transmission in Chile

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    Indexación: Scopus; Scielo.Bartonella henselae es el agente causal de la enfermedad del arañazo del gato en personas inmunocompetentes y de la angiomatosis bacilar y peliosis hepatis en inmunocomprometidos. En Chile la prevalencia de anticuerpos contra B. henselae en niños y adolescentes sanos es de 13,3%, en personas con riesgo ocupacional 60,5% y en gatos 85,6%. No existen datos publicados respecto de la seroprevalencia en donantes de sangre en nuestro país, por lo que determinar si B. henselae se encuentra presente en la sangre de los donantes al momento de la donación es muy importante, ya que este microorganismo puede sobrevivir hasta 35 días en los eritrocitos almacenados en banco de sangre a 4 °C. Objetivo: Determinar la prevalencia de B. henselae en donantes de sangre. Metodología: Se analizaron 140 muestras de sangre de donantes, para detectar la presencia de B. henselae, utilizando la técnica de la reacción de polimerasa en cadena (RPC). Resultados: Se obtuvo 13,6% de los donantes de sangre con RPC positiva para la B. henselae. La secuencia de los fragmentos amplificados presentó una identidad por sobre 98% con respecto a secuencias de B. henselae de referencia. Conclusión: El riesgo de transmisión sanguínea debiera ser considerado en un país con alta seroprevalencia de infección por B. henselae.Bartonella henselae is the causal agent of cat scratch disease in immunocompetent persons and bacterial angiomatosis in immunocompromised patients. In Chile, the prevalence of antibodies against B. henselae in healthy children and adolescents is 13.3%, in persons with occupational risk 60.5%, and in cats 85.6%. There are no published data regarding the seroprevalence in blood donors in our country, so determining if B. henselae is present in the blood of donors at the time of donation is very important, since this microorganism can survive up to 35 days in the red blood cells stored in a blood bank at 4 °C. Objective: To determine the prevalence of B. henselae in blood donors. Methodology: 140 donor blood samples were analyzed to detect the presence of B. henselae, using the polymerase chain reaction technique. Results: 13.6% of the blood donors with positive polymerase chain reaction for B. henselae were obtained. The sequence of the amplified fragments showed an identity of over 98% with respect to B. henselae reference sequences. Conclusion: The risk of blood transmission is due to a country with high B. henselae infection.https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0716-10182017000600539&lng=en&nrm=iso&tlng=e

    Expression of Regulatory Platelet MicroRNAs in Patients with Sickle Cell Disease

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    Background: Increased platelet activation in sickle cell disease (SCD) contributes to a state of hypercoagulability and confers a risk of thromboembolic complications. The role for post-transcriptional regulation of the platelet transcriptome by microRNAs (miRNAs) in SCD has not been previously explored. This is the first study to determine whether platelets from SCD exhibit an altered miRNA expression profile. Methods and Findings: We analyzed the expression of miRNAs isolated from platelets from a primary cohort (SCD = 19, controls = 10) and a validation cohort (SCD = 7, controls = 7) by hybridizing to the Agilent miRNA microarrays. A dramatic difference in miRNA expression profiles between patients and controls was noted in both cohorts separately. A total of 40 differentially expressed platelet miRNAs were identified as common in both cohorts (p-value 0.05, fold change>2) with 24 miRNAs downregulated. Interestingly, 14 of the 24 downregulated miRNAs were members of three families - miR-329, miR-376 and miR-154 - which localized to the epigenetically regulated, maternally imprinted chromosome 14q32 region. We validated the downregulated miRNAs, miR-376a and miR-409-3p, and an upregulated miR-1225-3p using qRT-PCR. Over-expression of the miR-1225-3p in the Meg01 cells was followed by mRNA expression profiling to identify mRNA targets. This resulted in significant transcriptional repression of 1605 transcripts. A combinatorial approach using Meg01 mRNA expression profiles following miR-1225-3p overexpression, a computational prediction analysis of miRNA target sequences and a previously published set of differentially expressed platelet transcripts from SCD patients, identified three novel platelet mRNA targets: PBXIP1, PLAGL2 and PHF20L1. Conclusions: We have identified significant differences in functionally active platelet miRNAs in patients with SCD as compared to controls. These data provide an important inventory of differentially expressed miRNAs in SCD patients and an experimental framework for future studies of miRNAs as regulators of biological pathways in platelets. © 2013 Jain et al

    A nonlinear mixed-effects modeling approach for ecological data: Using temporal dynamics of vegetation moisture as an example

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    Increasingly, often ecologist collects data with nonlinear trends, heterogeneous variances, temporal correlation, and hierarchical structure. Nonlinear mixed-effects models offer a flexible approach to such data, but the estimation and interpretation of these models present challenges, partly associated with the lack of worked examples in the ecological literature. We illustrate the nonlinear mixed-effects modeling approach using temporal dynamics of vegetation moisture with field data from northwestern Patagonia. This is a Mediterranean-type climate region where modeling temporal changes in live fuel moisture content are conceptually relevant (ecological theory) and have practical implications (fire management). We used this approach to answer whether moisture dynamics varies among functional groups and aridity conditions, and compared it with other simpler statistical models. The modeling process is set out “step-by-step”: We start translating the ideas about the system dynamics to a statistical model, which is made increasingly complex in order to include different sources of variability and correlation structures. We provide guidelines and R scripts (including a new self-starting function) that make data analyses reproducible. We also explain how to extract the parameter estimates from the R output. Our modeling approach suggests moisture dynamic to vary between grasses and shrubs, and between grasses facing different aridity conditions. Compared to more classical models, the nonlinear mixed-effects model showed greater goodness of fit and met statistical assumptions. While the mixed-effects approach accounts for spatial nesting, temporal dependence, and variance heterogeneity; the nonlinear function allowed to model the seasonal pattern. Parameters of the nonlinear mixed-effects model reflected relevant ecological processes. From an applied perspective, the model could forecast the time when fuel moisture becomes critical to fire occurrence. Due to the lack of worked examples for nonlinear mixed-effects models in the literature, our modeling approach could be useful to diverse ecologists dealing with complex data.Fil: Oddi, Facundo José. Universidad Nacional de Río Negro. Sede Andina. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Miguez, Fernando E.. University of Iowa; Estados UnidosFil: Ghermandi, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Bianchi, Lucas Osvaldo. Universidad Nacional de Río Negro. Sede Andina. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Garibaldi, Lucas Alejandro. Universidad Nacional de Río Negro. Sede Andina. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Statistical support for the hypothesis of developmental constraint in marsupial skull evolution.

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    Background: In contrast to placental neonates, in which all cranial bones are ossified, marsupial young have only the bones of the oral region and the exoccipital ossified at birth, in order to facilitate suckling at an early stage of development. In this study, we investigated whether this heterochronic shift in the timing of cranial ossification constrains cranial disparity in marsupials relative to placentals. Methods: We collected three-dimensional (3D) landmark data about the crania of a wide range of extant placentals and marsupials, and from six fossil metatherians (the clade including extant marsupials and their stem relatives), using a laser scanner and a 3D digitizer. Principal components analysis and delta variance tests were used to investigate the distribution and disparity of cranial morphology between different landmark sets (optimizing either number of landmarks or number of taxa) of the whole skull and of individual developmental or functional regions (neurocranium, viscerocranium, oral region) for extant placentals and marsupials. Marsupial and placental data was also compared based on shared ecological aspects including diet, habitat, and time of peak activity. Results: We found that the extant marsupial taxa investigated here occupy a much smaller area of morphospace than the placental taxa, with a significantly (P<0.01) smaller overall variance. Inclusion of fossil taxa did not significantly increase the variance of metatherian cranial shape. Fossil forms generally plotted close to or within the realm of their extant marsupial relatives. When the disparities of cranial regions were investigated separately, significant differences between placentals and marsupials were seen for the viscerocranial and oral regions, but not for the neurocranial region. Conclusion: These results support the hypothesis of developmental constraint limiting the evolution of the marsupial skull, and further suggest that the marsupial viscerocranium as a whole, rather than just the early-ossifying oral region, is developmentally constrained

    Optimization of atmospheric plasma treatment of LDPE films: Influence on adhesive properties and ageing behavior

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    One of the major disadvantages of low density polyethylene (LDPE) films is their poor adhesive properties. Therefore, LDPE films have been treated with atmospheric pressure air plasma in order to improve their surface properties. So as to simulate the possible conditions in an industrial process, the samples have been treated with two different sample distances (6 and 10 mm), and treatment rates between 100 and 1000 mm s-1. The different sample distances are the distance of the sample from the plasma source. The variation of the surface properties and adhesion characteristics of the films were investigated for different aging times after plasma exposure (up to 21 days) using contact angle measurement, atomic force microscopy, weight loss measurements and shear test. Results show that the treatment increases the polar component () and these changes improve adhesive properties of the material. After the twenty-first day, the ageing process causes a decrease of wettability and adhesive properties of the LDPE films (up to 60%).Fombuena Borrás, V.; García Sanoguera, D.; Sánchez Nacher, L.; Balart Gimeno, RA.; Boronat Vitoria, T. (2014). Optimization of atmospheric plasma treatment of LDPE films: Influence on adhesive properties and ageing behavior. Journal of Adhesion Science and Technology. 28(1):97-113. doi:10.1080/01694243.2013.847045S97113281Achilias, D. S., Roupakias, C., Megalokonomos, P., Lappas, A. A., & Antonakou, Ε. V. (2007). Chemical recycling of plastic wastes made from polyethylene (LDPE and HDPE) and polypropylene (PP). Journal of Hazardous Materials, 149(3), 536-542. doi:10.1016/j.jhazmat.2007.06.076Friedman, M., & Walsh, G. (2002). High performance films: Review of new materials and trends. Polymer Engineering & Science, 42(8), 1756-1788. doi:10.1002/pen.11069Wiles, D. M., & Scott, G. (2006). Polyolefins with controlled environmental degradability. 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Study of Surface Properties of Polyolefins Modified by Corona Discharge Plasma. Plasma Processes and Polymers, 3(4-5), 355-364. doi:10.1002/ppap.200500163Arpagaus, C., Rossi, A., & Rudolf von Rohr, P. (2005). Short-time plasma surface modification of HDPE powder in a Plasma Downer Reactor – process, wettability improvement and ageing effects. Applied Surface Science, 252(5), 1581-1595. doi:10.1016/j.apsusc.2005.02.099Morra, M., Occhiello, E., Marola, R., Garbassi, F., Humphrey, P., & Johnson, D. (1990). On the aging of oxygen plasma-treated polydimethylsiloxane surfaces. Journal of Colloid and Interface Science, 137(1), 11-24. doi:10.1016/0021-9797(90)90038-pKim, K. S., Ryu, C. M., Park, C. S., Sur, G. S., & Park, C. E. (2003). Investigation of crystallinity effects on the surface of oxygen plasma treated low density polyethylene using X-ray photoelectron spectroscopy. Polymer, 44(20), 6287-6295. doi:10.1016/s0032-3861(03)00674-8Kim, S. H., Ha, H. J., Ko, Y. K., Yoon, S. J., Rhee, J. M., Kim, M. S., … Khang, G. (2007). Correlation of proliferation, morphology and biological responses of fibroblasts on LDPE with different surface wettability. Journal of Biomaterials Science, Polymer Edition, 18(5), 609-622. doi:10.1163/156856207780852514Borcia, G., Anderson, C. A., & Brown, N. M. D. (2004). The surface oxidation of selected polymers using an atmospheric pressure air dielectric barrier discharge. Part I. Applied Surface Science, 221(1-4), 203-214. doi:10.1016/s0169-4332(03)00879-1Pascual, M., Calvo, O., Sanchez-Nácher, L., Bonet, M. A., Garcia-Sanoguera, D., & Balart, R. (2009). Optimization of adhesive joints of low density polyethylene (LDPE) composite laminates with polyolefin foam using corona discharge plasma. Journal of Applied Polymer Science, 114(5), 2971-2977. doi:10.1002/app.30906Encinas, N., Díaz-Benito, B., Abenojar, J., & Martínez, M. A. (2010). Extreme durability of wettability changes on polyolefin surfaces by atmospheric pressure plasma torch. Surface and Coatings Technology, 205(2), 396-402. doi:10.1016/j.surfcoat.2010.06.069Takke, V., Behary, N., Perwuelz, A., & Campagne, C. (2009). Studies on the atmospheric air-plasma treatment of PET (polyethylene terephtalate) woven fabrics: Effect of process parameters and of aging. Journal of Applied Polymer Science, 114(1), 348-357. doi:10.1002/app.30618Awaja, F., Gilbert, M., Kelly, G., Fox, B., & Pigram, P. J. (2009). Adhesion of polymers. Progress in Polymer Science, 34(9), 948-968. doi:10.1016/j.progpolymsci.2009.04.007Garcia, D., Sanchez, L., Fenollar, O., Lopez, R., & Balart, R. (2008). Modification of polypropylene surface by CH4–O2 low-pressure plasma to improve wettability. Journal of Materials Science, 43(10), 3466-3473. doi:10.1007/s10853-007-2322-2Guimond, S., & Wertheimer, M. R. (2004). Surface degradation and hydrophobic recovery of polyolefins treated by air corona and nitrogen atmospheric pressure glow discharge. 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Study by XPS of an Atmospheric Plasma-Torch Treated Glass: Influence on Adhesion. Journal of Adhesion Science and Technology, 24(11-12), 1841-1854. doi:10.1163/016942410x507614Lommatzsch, U., Pasedag, D., Baalmann, A., Ellinghorst, G., & Wagner, H.-E. (2007). Atmospheric Pressure Plasma Jet Treatment of Polyethylene Surfaces for Adhesion Improvement. Plasma Processes and Polymers, 4(S1), S1041-S1045. doi:10.1002/ppap.200732402Balu, B., Berry, A. D., Patel, K. T., Breedveld, V., & Hess, D. W. (2011). Directional Mobility and Adhesion of Water Drops on Patterned Superhydrophobic Surfaces. Journal of Adhesion Science and Technology, 25(6-7), 627-642. doi:10.1163/016942410x525849Bhattacharya, S., Singh, R. K., Mandal, S., Ghosh, A., Bok, S., Korampally, V., … Gangopadhyay, S. (2010). Plasma Modification of Polymer Surfaces and Their Utility in Building Biomedical Microdevices. 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    Molecular and cellular mechanisms underlying the evolution of form and function in the amniote jaw.

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    The amniote jaw complex is a remarkable amalgamation of derivatives from distinct embryonic cell lineages. During development, the cells in these lineages experience concerted movements, migrations, and signaling interactions that take them from their initial origins to their final destinations and imbue their derivatives with aspects of form including their axial orientation, anatomical identity, size, and shape. Perturbations along the way can produce defects and disease, but also generate the variation necessary for jaw evolution and adaptation. We focus on molecular and cellular mechanisms that regulate form in the amniote jaw complex, and that enable structural and functional integration. Special emphasis is placed on the role of cranial neural crest mesenchyme (NCM) during the species-specific patterning of bone, cartilage, tendon, muscle, and other jaw tissues. We also address the effects of biomechanical forces during jaw development and discuss ways in which certain molecular and cellular responses add adaptive and evolutionary plasticity to jaw morphology. Overall, we highlight how variation in molecular and cellular programs can promote the phenomenal diversity and functional morphology achieved during amniote jaw evolution or lead to the range of jaw defects and disease that affect the human condition

    Skeleton of an unusual cat-sized marsupial relative (Metatheria: Marsupialiformes) from the middle Eocene (Lutetian: 44-43 million years ago) of Turkey

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    We describe a near-complete, three-dimensionally preserved skeleton of a metatherian (relative of modern marsupials) from the middle Eocene (Lutetian: 44–43 million years ago) Lülük member of the Uzunçarşıdere Formation, central Turkey. With an estimated body mass of 3–4 kg, about the size of a domestic cat (Felis catus) or spotted quoll (Dasyurus maculatus), it is an order of magnitude larger than the largest fossil metatherians previously known from the Cenozoic of the northern hemisphere. This new taxon is characterised by large, broad third premolars that probably represent adaptations for hard object feeding (durophagy), and its craniodental morphology suggests the capacity to generate high bite forces. Qualitative and quantitative functional analyses of its postcranial skeleton indicate that it was probably scansorial and relatively agile, perhaps broadly similar in locomotor mode to the spotted quoll, but with a greater capacity for climbing and grasping. Bayesian phylogenetic analysis of a total evidence dataset comprising 259 morphological characters and 9kb of DNA sequence data from five nuclear protein-coding genes, using both undated and “tip-and-node dating” approaches, place the new taxon outside the marsupial crown-clade, but within the clade Marsupialiformes. It demonstrates that at least one metatherian lineage evolved to occupy the small-medium, meso- or hypo-carnivore niche in the northern hemisphere during the early Cenozoic, at a time when there were numerous eutherians (placentals and their fossil relatives) filling similar niches. However, the known mammal fauna from Uzunçarşıdere Formation appears highly endemic, and geological evidence suggests that this region of Turkey was an island for at least part of the early Cenozoic, and so the new taxon may have evolved in isolation from potential eutherian competitors. Nevertheless, the new taxon reveals previously unsuspected ecomorphological disparity among northern hemisphere metatherians during the first half of the Cenozoic

    New and conventional strategies for lung recruitment in acute respiratory distress syndrome

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    Mechanical ventilation is a supportive and life saving therapy in patients with acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Despite advances in critical care, mortality remains high. During the last decade, the fact that mechanical ventilation can produce morphologic and physiologic alterations in the lungs has been recognized. In this context, the use of low tidal volumes (VT) and limited inspiratory plateau pressure (Pplat) has been proposed when mechanically ventilating the lungs of patients with ALI/ARDS, to prevent lung as well as distal organ injury. However, the reduction in VT may result in alveolar derecruitment, cyclic opening and closing of atelectatic alveoli and distal small airways leading to ventilator-induced lung injury (VILI) if inadequate low positive end-expiratory pressure (PEEP) is applied. On the other hand, high PEEP levels may be associated with excessive lung parenchyma stress and strain and negative hemodynamic effects, resulting in systemic organ injury. Therefore, lung recruitment maneuvers have been proposed and used to open up collapsed lung, while PEEP counteracts alveolar derecruitment due to low VT ventilatio
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