Cosmological Bianchi Class A models in S\'aez-Ballester theory

We use the S\'aez-Ballester (SB) theory on anisotropic Bianchi Class A cosmological model, with barotropic fluid and cosmological constant, using the Hamilton or Hamilton-Jacobi approach. Contrary to claims in the specialized literature, it is shown that the S\'aez-Ballester theory cannot provide a realistic solution to the dark matter problem of Cosmology for the dust epoch, without a fine tunning because the contribution of the scalar field in this theory is equivalent to a stiff fluid (as can be seen from the energy--momentum tensor for the scalar field), that evolves in a different way as the dust component. To have similar contributions of the scalar component and the dust component implies that their past values were fine tunned. So, we reinterpreting this null result as an indication that dark matter plays a central role in the formation of structures and galaxy evolution, having measureable effects in the cosmic microwave bound radiation, and than this formalism yield to this epoch as primigenius results. We do the mention that this formalism was used recently in the so called K-essence theory applied to dark energy problem, in place to the dark matter problem. Also, we include a quantization procedure of the theory which can be simplified by reinterpreting the theory in the Einstein frame, where the scalar field can be interpreted as part of the matter content of the theory, and exact solutions to the Wheeler-DeWitt equation are found, employing the Bianchi Class A cosmological models.Comment: 24 pages; ISBN: 978-953-307-626-3, InTec

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The Effectiveness of a Group Motor Skill Intervention Program in Children with Developmental Coordination Disorder: Program Frequency Matters.

Purpose: The purpose of this study was to investigate the effects of two group programs on visual-motor integration, motor proficiency, gross-motor skills, and parental perception of motor difficulties in children with developmental coordination disorder (DCD). We compared whether the frequency of two programs (10 one hour sessions - once/week for 10 weeks verses 24 one hour sessions – twice/week for 12 weeks) produced different changes in motor skills. Methods: Children in the two programs were assessed before and after each program with the MABC-2, DCD-Q, BOT-2, Beery-VMI-6, and the TGMD-2 assessments. The emphasis of the programs was on group activities that required collaboration while performing skills that utilized upper-body coordination, balance, and fine-motor abilities. Results: After the 24-session intervention program, results revealed significant improvements in the Manual Coordination and Total Score of the BOT-2 (ps \u3c .05), and parents reported significantly higher scores for all categories of the DCD-Q (ps \u3c .05). No significant changes were observed after the 10-session once/week intervention program. Conclusions: We conclude that a (24 one-hour sessions- twice a week for 12 weeks) group intervention program can be an effective intervention method for improvement of motor skills in children with DCD. We recommend that allied health professionals consider the group intervention as a feasible way to promote more frequent sessions to children with DCD

Getting Smart (Grids): An Efficiency Frontier Assessment

Information and communication technology are reshaping the electricity industry, with economic, environmental, and regulatory consequences. Smart grids allow the growing integration of renewable energy sources, a horizontalization of the roles of producers and consumers, a flatter demand profile which save investments intended to supply peaks of consumption, idle at great extent off-peaks. On the other hand, smart grids require important investments for modernizing technology. Concerning our objectives, firstly, we seek to understand the conceptual consequences of the irruption of smart grids on the electricity sector, and its importance for renewables adoption. Secondly, we discuss policies and regulations needed to accelerate the transformation of the electricity network in a smart grid, and to increase the renewables? share on total energy. Thirdly, our empirical approach runs a Data Envelopment Analysis (DEA) model to estimate the efficiency gains in the transition between traditional and smart grids. Our results show the efficiency levels of those countries whose objective is to deliver electricity with high levels of quality of services, and at the same time, using more renewables (with fewer carbon emissions), and low cost of supply. We conclude discussing the implications of our empirical model, the limitations, and next stages in polishing the results.Fil: Ferro, Gustavo Adolfo. Universidad del Cema; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Romero, Carlos Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Interdisciplinario de Economía Política de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Económicas. Instituto Interdisciplinario de Economía Política de Buenos Aires; ArgentinaFil: Ramos, Maria Priscila. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Interdisciplinario de Economía Política de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Económicas. Instituto Interdisciplinario de Economía Política de Buenos Aires; ArgentinaLV Reunión Anual Asociación Argentina de Economía PolíticaCiudad Autónoma de Buenos AiresArgentinaAsociación Argentina de Economía Polític

Selective cytotoxicity of PAMAM G5 core-PAMAM G2.5 shell tecto-dendrimers on melanoma cells

Background: The controlled introduction of covalent linkages between dendrimer building blocks leads to polymers of higher architectural order known as tecto-dendrimers. Because of the few simple steps involved in their synthesis, tecto-dendrimers could expand the portfolio of structures beyond commercial dendrimers, due to the absence of synthetic drawbacks (large number of reaction steps, excessive monomer loading, and lengthy chromatographic separations) and structural constraints of high-generation dendrimers (reduction of good monodispersity and ideal dendritic construction due to de Gennes dense-packing phenomenon). However, the biomedical uses of tecto-dendrimers remain unexplored. In this work, after synthesizing saturated shell core-shell tecto-dendrimers using amine-terminated polyamidoamine (PAMAM) generation 5 (G5) as core and carboxyl-terminated PAMAM G2.5 as shell (G5G2.5 tecto-dendrimers), we surveyed for the first time the main features of their interaction with epithelial cells. Methods: Structural characterization of G5G2.5 was performed by polyacrylamide gel electrophoresis, matrix-assisted laser desorption time-of-flight mass spectrometry, and microscopic techniques; their hydrodynamic size and Z-potential was also determined. Cellular uptake by human epidermal keratinocytes, colon adenocarcinoma, and epidermal melanoma (SK-Mel-28) cells was determined by flow cytometry. Cytotoxicity was determined by mitochondrial activity, lactate dehydrogenase release, glutathione depletion, and apoptosis/necrosis measurement. Results: The resultant 60%-67% saturated shell, 87,000-dalton G5G2.5 (mean molecular weight) interacted with cells in a significantly different fashion in comparison to their building blocks and to its closest counterpart, PAMAM G6.5. After being actively taken up by epithelial cells, G5G2.5 caused cytotoxicity only on SK-Mel-28 cells, including depletion of intracellular glutathione and fast necrosis that was manifested above 5 μM G5G2.5. It cannot be discounted that traces of LiCl within G5G2.5 were involved in such deleterious effects. Conclusion: These preliminary results suggest that at concentrations that do not damage healthy keratinocytes, G5G2.5 could display antimelanoma activity.Centro de Investigaciones Cardiovasculare

Incidencia de higiene y seguridad laboral en la empresa IMEXA

La presente investigación se realizó en el municipio de Ocotal durante el II semestre del 2016, en la empresa de Importaciones y Exportaciones Argueta; el propósito de fue identificar los riesgos más frecuentes y los factores que afectan en el desempeño laboral a cada uno de los colaboradores de IMEXA, de esta manera se plantea un plan de medidas correctivas que permitirán mejorar el desempeño laboral de sus trabajadores. El tipo de investigación es aplicada y su enfoque cuantitativo. El tipo de muestra se realizó a través del censo donde se aplicó la encuesta a 89 trabajadores de IMEXA, y sus datos fueron procesados en el programa de SPSS versión 22.5. Teniendo como resultado que las medidas más frecuentes que usa IMEXA son: medidas de accidentes, medidas de robo y medidas de incendios utilizándolas de forma correcta y eficiente y uno de los factores que afecta el desempeño altamente es el clima laboral con un 44.9%; y para ello, se propone un plan de acción para mejorar el desempeño laboral de la empresa

Incidencia de higiene y seguridad en el desempeño laboral de la empresa IMEXA de Ocotal en el II semestre 2016

La presente investigación se realizó en el municipio de Ocotal durante el II semestre del 2016, en la empresa de Importaciones y Exportaciones Argueta; el propósito fue identificar los riesgos más frecuentes y los factores que afectan en el desempeño laboral a cada uno de los colaboradores de IMEXA, de esta manera se plantea un plan de medidas correctivas que permitirán mejorar el desempeño laboral de sus trabajadores. El tipo de investigación es aplicada y su enfoque cuantitativo. El tipo de muestra se realizó a través del censo donde se aplicó la encuesta a 89 colaboradores de IMEXA, y sus datos fueron procesados en el programa de SPSS versión 22.5. Teniendo como resultado que las medidas más frecuentes que usa IMEXA son: medidas de accidentes, medidas de robo y medidas de accidentes utilizándolas de forma correcta y eficiente y uno de los factores que afecta el desempeño altamente es el clima laboral con un 44.9%, y para ello se propone un plan de acción para mejorar el desempeño laboral de la empresa

Gas natural no convencional en la argentina: situación actual, obstáculos e impacto potencial

El objetivo del presente trabajo es describir las características tecnológicas de la producción de gas natural no convencional, el impacto que tendría el aumento de su oferta, los obstáculos que la limitan y las alternativas de política que contribuirían al desarrollo en gran escala de Vaca Muerta. La principal limitante para el desarrollo de Vaca Muerta es la demanda de Gas Natural doméstica e internacional. Por cuestiones de eficiencia energética y madurez y grado de cobertura existente hay poco espacio para expandir la demanda doméstica, salvo con políticas explícitas en el sector de transporte y por la sustitución de otros energéticos en la industria. En este contexto, la demanda internacional es clave, se prevé un aumento de ésta, en particular del este asiático, pero también mayor competencia de otros productores. En este contexto, aprovechar el impacto que tendría Vaca Muerta sobre el PBI, de alrededor de un tercio de punto anual de crecimiento, y sobre las cuentas externas, pudiendo llegar a tener en el futuro superávit comercial energético, requiere la implementación y coordinación de diversas políticas sectoriales.The objective of this paper is to describe the technological characteristics of the production of unconventional natural gas, the impact that the increase in its supply would have, the obstacles that limit it and the policy alternatives that would contribute to the large-scale development of Vaca Muerta. The main limitation for the development of Vaca Muerta is the demand for domestic and international Natural Gas. Due to issues of energy efficiency and maturity and the degree of coverage, there is little room to expand domestic demand, except with explicit policies in the transport sector and the replacement of other energy sources in the industry. In this context, international demand is key, and its increase is expected, particularly from East Asia, but also greater competition from other producers. In this context, taking advantage of the impact that Vaca Muerta would have on the GDP, of about one third of annual growth point, and on the external accounts, being able to have in the future energy trade surplus, requires the implementation and coordination of various sectoral policie.Fil: Romero, Carlos Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Interdisciplinario de Economía Política de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Económicas. Instituto Interdisciplinario de Economía Política de Buenos Aires; ArgentinaFil: Ramos, Maria Priscila. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Interdisciplinario de Economía Política de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Económicas. Instituto Interdisciplinario de Economía Política de Buenos Aires; ArgentinaLIV Reunion Anual de la Asociación Argentina de Economía PolíticaBahía BlancaArgentinaUniversidad Nacional del Sur. Departamento de EconomíaAsociación Argentina de Economía Polític

Nutrologia e nutrição em unidade de terapia intensiva: sinergia em busca de excelência

Objective: Nutritional therapy, in spite of current guidelines, does not seem to be perceived yet as an important therapeutic strategy in critical patients. The objective of this study was to assess the joint action of a team composed of a nutrology specialist and a nutritionist in ICU by measuring quality indicators such as fasting time and adequacy of caloric intake. Methods: This is a prospective descriptive study realized in a mixed adult intensive care unit, with patients that remained stayed for longer than 24h. Patients received nutritional therapy according to a protocol based on guidelines and adapted to the unit. Demographic and clinical data were gathered; nutritional route, time of start of therapy, prescribed volume, and received volume of enteral feeding. Results: Out of 89 patients assessed, 48 (53.9%) started with oral feeding, 2 (2.2%) received parenteral feeding, and 39 (43.8%), enteral feeding. The time for enteral therapy to start was 24h and 25 minutes (QI: 7-44h), and 87.2% of patients received enteral feeding in the first 48h of stay. For surgical patients (n=42), the time to start feeding via any route was 20h and 59 minutes (QI: 14h 45 min - 41h 15 min). 87% of the calories prescribed were instilled via enteral feeding throughout the 284 days of assessment. Conclusion: The presence of a team composed of a nutrology specialist and a nutritionist may be capable of meeting the attention and specific knowledge in nutritional therapy needs, bringing high quality and proven excellence through the indicators measured