Dos modelos de aplicación del método del valor ganado (EVM) para el sector de la construcción

El método de gestión del valor ganado (Earned Value Management, EVM) no es muy habitual en el sector de la construcción. Las grandes empresas constructoras han desarrollado sus propios sistemas de información, ya que no existe una adaptación del EVM al modelo económico específico de este sector, y las empresas pequeñas y los profesionales lo desconocen. Esta comunicación desarrolla dos modelos diferentes de aplicación del EVM: para el profesional que dirige la ejecución de obras, que necesita un modelo simplificado, basado en la información de que dispone, y la pequeña empresa constructora, que requiere un modelo más complejo, ya que en su sistema de gestión de costes estimados y reales tiene que integrar también los ingresos. Los modelos se han implementado en Presto, un programa de amplia difusión en la construcción, proponiendo los cambios necesarios para que los profesionales y las pequeñas empresas obtengan todos los resultados del EVM a partir de datos que ya utilizan habitualmente en su trabajo. Pueden sustituir así su visión pasiva, limitada a registrar lo que ocurre en la obra, por una estrategia activa, que les permite tomar decisiones para corregir a tiempo las posibles desviaciones de la obra

Montecarlo method applied to comparison of tenders in construction projects.

La comparación de las diferentes ofertas presentadas en la licitación de un proyecto,con el sistema de contratación tradicional de medición abierta y precio unitario cerrado, requiere herramientas de análisis que sean capaces de discriminar propuestas que teniendo un importe global parecido pueden presentar un impacto económico muy diferente durante la ejecución. Una de las situaciones que no se detecta fácilmente con los métodos tradicionales es el comportamiento del coste real frente a las variaciones de las cantidades realmente ejecutadas en obra respecto de las estimadas en el proyecto. Este texto propone abordar esta situación mediante un sistema de análisis cuantitativo del riesgo como el método de Montecarlo. Este procedimiento, como es sabido, consiste en permitir que los datos de entrada que definen el problema varíen unas funciones de probabilidad definidas, generar un gran número de casos de prueba y tratar los resultados estadísticamente para obtener los valores finales más probables,con los parámetros necesarios para medir la fiabilidad de la estimación. Se presenta un modelo para la comparación de ofertas, desarrollado de manera que puede aplicarse en casos reales aplicando a los datos conocidos unas condiciones de variación que sean fáciles de establecer por los profesionales que realizan estas tareas. ABSTRACT: The comparison of the different bids in the tender for a project, with the traditional contract system based on unit rates open to and re-measurement, requires analysis tools that are able to discriminate proposals having a similar overall economic impact, but that might show a very different behaviour during the execution of the works. One situation not easily detected by traditional methods is the reaction of the actual cost to the changes in the exact quantity of works finally executed respect of the work estimated in the project. This paper intends to address this situation through the Monte Carlo method, a system of quantitative risk analysis. This procedure, as is known, is allows the input data defining the problem to vary some within well defined probability functions, generating a large number of test cases, the results being statistically treated to obtain the most probable final values, with the rest of the parameters needed to measure the reliability of the estimate. We present a model for the comparison of bids, designed in a way that it can be applied in real cases, based on data and assumptions that are easy to understand and set up by professionals who wish to perform these tasks

Quick time planning using "s" curves and cost based durations.

ABSTRACT: The comparison of the different bids in the tender for a project, with the traditional contract system based on unit rates open to and re-measurement, requires analysis tools that are able to discriminate proposals having a similar overall economic impact, but that might show a very different behaviour during the execution of the works. RESUMEN: La estimación rápida de costes en fases iniciales del proyecto por métodos paramétricos y referencias estadísticas es un tema bien estudiado, divulgado y aplicado en el sector de la construcción. Sin embargo, existe poca literatura técnica sobre sistemas de predimensionado de tiempos, que permitan realizar rápidamente una planificación con un grado de aproximación razonable. Este texto reúne dos aspectos ya conocidos, pero hasta ahora independientes, y una aportación propia: -La estimación del plazo final por referencias estadísticas (BCIS, 2000) - La estimación del reparto del coste total a lo largo de la ejecución mediante curvas "S" (diversos autores) La estimación de la duración de la ejecución de las actividades en función de su coste. El conjunto de estas tres técnicas, aplicadas a un proyecto, permite obtener una planificación con el suficiente grado de detalle y fiabilidad para tomar decisiones en fases iniciales del proyecto

The influence of the complex topography and dynamic history of the montane Neotropics on the evolutionary differentiation of a cloud forest bird (Premnoplex brunnescens, Furnariidae)

Aim: To examine the effect of geographical barriers and habitat dynamics related to climatic oscillations on the phylogeography of a widespread passerine of Neotropical cloud forests, the spotted barbtail (Premnoplex brunnescens). Location: Neotropical humid forests of montane areas in lower Central America and South America. Methods: We sequenced two mitochondrial genes and one nuclear intron from specimens collected across the distribution of P. brunnescens. Phylogenetic relationships were inferred using Bayesian and maximum-likelihood methods. Groups with maximum differentiation were estimated with spatial analysis of molecular variance (SAMOVA). We estimated timing of differentiation and relationships among groups with a species-tree approach and historical demography with extended Bayesian skyline plots. Results: Six highly differentiated clades of P. brunnescens are distributed in lower Central America, Sierra Nevada de Santa Marta, northern Venezuelan mountains, the Northern Andes, central Peru, and southern Peru and Bolivia. Within the Northern Andes clade, six phylogroups were identified associated with different slopes and isolated cordilleras. Most clades occupy opposite sides of low-lying valleys and ridgelines, but little differentiation was observed across several putative barriers. Population divergence occurred in the late Miocene and Pliocene, perhaps in association with Andean uplift. Historical fluctuations in population sizes suggest that populations tracked the spatial dynamics of montane forests associated with glacial cycles. Main conclusions: Extensive genetic differentiation in mitochondrial and nuclear DNA exists among populations of P. brunnescens. Such marked divergence was probably promoted by the rugged topography and dynamic ecological history of the Neotropical mountains. Our study sheds light on mechanisms promoting population differentiation in the montane Neotropics. © 2014 John Wiley & Sons Ltd

Enhanced monography in a collaboratively evolved hub for systematic biology

No abstract available

La influencia de la responsabilidad social empresarial en el comportamiento de compra de las consumidoras de revistas de 18 a 24 años de edad en Lima Metropolitana

La responsabilidad social empresarial (RSE) se ha convertido en un tema de importancia a nivel internacional, sin embargo en el Perú aún no se observan muchos estudios que permitan conocer su impacto en el consumidor. Por tanto, esta investigación busca determinar la influencia de la Responsabilidad Social Empresarial en el comportamiento de compra de las consumidoras de revistas cuyas edades se encuentran entre 18 a 24 años en Lima Metropolitana. Para cuantificar la intención de compra y la disposición a pagar por las acciones de responsabilidad social desarrolladas por las empresas, se realizó una investigación bajo la Metodología de los Modelos de Elección Discreta. Dicho experimento se llevó a cabo utilizando una muestra por conveniencia de 132 consumidoras de revistas cuyas edades se encuentran entre 18 a 24 años en Lima Metropolitana. La investigación brinda evidencia empírica de la relación positiva entre la Responsabilidad Social Empresarial y el comportamiento de compra de la muestra. Los resultados del estudio indican que el efecto de la Responsabilidad Social Empresarial en su conjunto es superior al de las Competencias Corporativas. El presente estudio es una ampliación del alcance de la investigación doctoral La Influencia de la Responsabilidad Social Empresarial en el Comportamiento de Compra de los Consumidores Peruanos (Marquina, 2009). Con la autorización del autor, se ha utilizado la tesis como base para la revisión de literatura y la aplicación de la metodología.Corporate Social Responsibility has become a matter of importance at an international level, also in Peru there are not many studies that show its effect on the consumer. Therefore, this research seeks to determine the influence of Corporate Social Responsibility on consumer magazine’s buying behavior whose ages are between 18-24 years in Metropolitan Lima. To quantify the purchase intention and the disposition to pay for the corporate social responsibility actions developed by companies an experiment was carried out under the discrete choice model. This experiment was carried out using a random for convenience of 132 consumer magazine’s buying whose ages are between 18-24 years in Metropolitan Lima. This investigation provides empirical evidence of the positive relationship between the corporate social responsibility and the purchasing behavior of the sample. The results of the study indicate that the effect of the corporate social responsibility as a whole is superior to that of the corporate competencies. The present study is an extension of the scope of the doctoral investigation “The Influence of the Corporate Social Responsibility in the Purchasing Behavior of Peruvian Consumers” (Marquina, 2009). With permission of the author, the thesis has been used as the basis for the literature review and application of the methodology.Tesi

Acute abdomen secondary to dependent rectus sheath hematoma: a case report

The rectus sheath hematoma as a rare clinical entity and self-limited, resulting from the accumulation of blood within the sheath of the rectus abdominis, secondary to breakage the epigastric artery higher or lower, or direct damage by fiber tear of rectus abdominis muscle. Female patient, 37 years old, enters the service of emergencies by refer abdominal pain of sudden onset, diffuse, with 5 hours of evolution with irradiation to lumbar region ipsilateral. In the CT scan in single stage and with IV contrast, it was reported an asymmetry in the thickness of the muscles of the anterior wall at the expense of a lesion of occupying space dependent anterior rectus muscle, as diagnostic impression is concluded a intramuscular injury dependent of the right anterior abdominal straight; likely bruising of the sheath of the straight abdominal by what is being decided its income to operating room to perform surgical drainage and epigastric vessel ligation. for the general doctor, specialist and it is important to take into account the pathology, symptoms, diagnostic and therapeutic strategy for a hematoma dependent of the rectus abdominis muscle, due to the high percentage of error diagnosis in patients who are admitted to the emergency department with acute abdominal pain, because you can Confused with other abdominal pathologies, which shows the importance of an appropriate differential diagnosis, and treatment prescribed, which optimize and reduce unnecessary intervention as well as morbidity and mortality of this disease

To which world regions does the valence–dominance model of social perception apply?

Over the past 10 years, Oosterhof and Todorov’s valence–dominance model has emerged as the most prominent account of how people evaluate faces on social dimensions. In this model, two dimensions (valence and dominance) underpin social judgements of faces. Because this model has primarily been developed and tested in Western regions, it is unclear whether these findings apply to other regions. We addressed this question by replicating Oosterhof and Todorov’s methodology across 11 world regions, 41 countries and 11,570 participants. When we used Oosterhof and Todorov’s original analysis strategy, the valence–dominance model generalized across regions. When we used an alternative methodology to allow for correlated dimensions, we observed much less generalization. Collectively, these results suggest that, while the valence–dominance model generalizes very well across regions when dimensions are forced to be orthogonal, regional differences are revealed when we use different extraction methods and correlate and rotate the dimension reduction solution.C.L. was supported by the Vienna Science and Technology Fund (WWTF VRG13-007); L.M.D. was supported by ERC 647910 (KINSHIP); D.I.B. and N.I. received funding from CONICET, Argentina; L.K., F.K. and Á. Putz were supported by the European Social Fund (EFOP-3.6.1.-16-2016-00004; ‘Comprehensive Development for Implementing Smart Specialization Strategies at the University of Pécs’). K.U. and E. Vergauwe were supported by a grant from the Swiss National Science Foundation (PZ00P1_154911 to E. Vergauwe). T.G. is supported by the Social Sciences and Humanities Research Council of Canada (SSHRC). M.A.V. was supported by grants 2016-T1/SOC-1395 (Comunidad de Madrid) and PSI2017-85159-P (AEI/FEDER UE). K.B. was supported by a grant from the National Science Centre, Poland (number 2015/19/D/HS6/00641). J. Bonick and J.W.L. were supported by the Joep Lange Institute. G.B. was supported by the Slovak Research and Development Agency (APVV-17-0418). H.I.J. and E.S. were supported by a French National Research Agency ‘Investissements d’Avenir’ programme grant (ANR-15-IDEX-02). T.D.G. was supported by an Australian Government Research Training Program Scholarship. The Raipur Group is thankful to: (1) the University Grants Commission, New Delhi, India for the research grants received through its SAP-DRS (Phase-III) scheme sanctioned to the School of Studies in Life Science; and (2) the Center for Translational Chronobiology at the School of Studies in Life Science, PRSU, Raipur, India for providing logistical support. K. Ask was supported by a small grant from the Department of Psychology, University of Gothenburg. Y.Q. was supported by grants from the Beijing Natural Science Foundation (5184035) and CAS Key Laboratory of Behavioral Science, Institute of Psychology. N.A.C. was supported by the National Science Foundation Graduate Research Fellowship (R010138018). We acknowledge the following research assistants: J. Muriithi and J. Ngugi (United States International University Africa); E. Adamo, D. Cafaro, V. Ciambrone, F. Dolce and E. Tolomeo (Magna Græcia University of Catanzaro); E. De Stefano (University of Padova); S. A. Escobar Abadia (University of Lincoln); L. E. Grimstad (Norwegian School of Economics (NHH)); L. C. Zamora (Franklin and Marshall College); R. E. Liang and R. C. Lo (Universiti Tunku Abdul Rahman); A. Short and L. Allen (Massey University, New Zealand), A. Ateş, E. Güneş and S. Can Özdemir (Boğaziçi University); I. Pedersen and T. Roos (Åbo Akademi University); N. Paetz (Escuela de Comunicación Mónica Herrera); J. Green (University of Gothenburg); M. Krainz (University of Vienna, Austria); and B. Todorova (University of Vienna, Austria). The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.https://www.nature.com/nathumbehav/am2023BiochemistryGeneticsMicrobiology and Plant Patholog

To which world regions does the valence–dominance model of social perception apply?

Over the past 10 years, Oosterhof and Todorov’s valence–dominance model has emerged as the most prominent account of how people evaluate faces on social dimensions. In this model, two dimensions (valence and dominance) underpin social judgements of faces. Because this model has primarily been developed and tested in Western regions, it is unclear whether these findings apply to other regions. We addressed this question by replicating Oosterhof and Todorov’s methodology across 11 world regions, 41 countries and 11,570 participants. When we used Oosterhof and Todorov’s original analysis strategy, the valence–dominance model generalized across regions. When we used an alternative methodology to allow for correlated dimensions, we observed much less generalization. Collectively, these results suggest that, while the valence–dominance model generalizes very well across regions when dimensions are forced to be orthogonal, regional differences are revealed when we use different extraction methods and correlate and rotate the dimension reduction solution

A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.

The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world