El pedaleo en kayakistas escolares durante la preparación técnica en la EIDE de Guantánamo.

The research responds to the development strategy of the canoeing sport in the province and is part of the process of technical preparation of school kayakers at the EIDE in Guantánamo. The application of research methods showed that there are objective and subjective conditions that limit the apprehension of the motor habit of pedaling during rowing. Coordinated leg-hip work allows mobilizing the greatest number of muscles and improving joint amplitude during the execution of the rowing technique. The author proposes a system of actions to stimulate pedaling in school kayakers during technical preparation.La investigación responde a la estrategia de desarrollo del deporte canotaje en la provincia y se enmarca dentro del proceso de preparación técnica de kayakistas escolares en la EIDE de Guantánamo. La aplicación de métodos de investigación arroja que existen condiciones objetivas y subjetivas que limitan la aprehensión del hábito motor de pedalear durante la remada. El trabajo coordinado pierna y cadera, permite movilizar la mayor cantidad de músculos y mejorar la amplitud articular durante la ejecución de la técnica. El autor propone un sistema de acciones para estimular el pedaleo en kayakistas escolares durante la preparación técnica

Activation of effector immune cells promotes tumor stochastic extinction: A homotopy analysis approach

In this article we provide homotopy solutions of a cancer nonlinear model describing the dynamics of tumor cells in interaction with healthy and effector immune cells. We apply a semi-analytic technique for solving strongly nonlinear systems - the Step Homotopy Analysis Method (SHAM). This algorithm, based on a modification of the standard homotopy analysis method (HAM), allows to obtain a one-parameter family of explicit series solutions. By using the homotopy solutions, we first investigate the dynamical effect of the activation of the effector immune cells in the deterministic dynamics, showing that an increased activation makes the system to enter into chaotic dynamics via a period-doubling bifurcation scenario. Then, by adding demographic stochasticity into the homotopy solutions, we show, as a difference from the deterministic dynamics, that an increased activation of the immune cells facilitates cancer clearance involving tumor cells extinction and healthy cells persistence. Our results highlight the importance of therapies activating the effector immune cells at early stages of cancer progression

Why Customers Value Mass-customized Products: The Importance of Process Effort and Enjoyment

We test our hypotheses on 186 participants designing their own scarves with an MC toolkit. After completing the process, they submitted binding bids for "their" products in Vickrey auctions. We therefore observe real buying behavior, not merely stated intentions. We find that the subjective value of a self-designed product (i.e., one's bid in the course of the auction) is indeed not only impacted by the preference fit the customer expects it to deliver, but also by (1) the process enjoyment the customer reports, (2) the interaction of preference fit and process enjoyment, and (3) the interaction of preference fit and perceived process effort. In addition to its main effect, we interpret preference fit as a moderator of the valuegenerating effect of process evaluation: In cases where the outcome of the process is perceived as positive (high preference fit), the customer also interprets process effort as a positive accomplishment, and this positive affect adds (further) value to the product. It appears that the perception of the self-design process as a good or bad experience is partly constructed on the basis of the outcome of the process. In the opposite case (low preference fit), effort creates a negative affect which further reduces the subjective value of the product. Likewise, process enjoyment is amplified by preference fit, although enjoyment also has a significant main effect, which means that regardless of the outcome, customers attribute higher value to a self-designed product if they enjoy the process. The importance of the self-design process found in this study bears clear relevance for companies which offer or plan to offer MC systems. It is not sufficient to design MC toolkits in such a way that they allow customers to design products according to their preferences. The affect caused by this process is also highly important. Toolkits should therefore stimulate positive affective reactions and at the same time keep negative affect to a minimum. (authors' abstract

Flujo sanguíneo y ventilación pulmonares: ¿nuevo paradigma?

ResumenLa gravedad fue establecida como el factor determinante de las diferencias en la distribución de la ventilación y la perfusión pulmonares por John West, concepto que continúa exponiéndose hoy en día como principio básico de la fisiología pulmonar.Las imágenes diagnósticas modernas permiten demostrar que la gravedad no es el factor determinante de estas diferencias, hecho que genera grandes interrogantes sobre los conceptos que, entre muchos otros, sustentan la ventilación mecánica, los modos ventilatorios y la ventilación unipulmonar en decúbito lateral durante la cirugía de tórax.El presente artículo reflexiona sobre los recientes hallazgos de los estudios sobre perfusión y ventilación que cuestionan el paradigma de la gravedad como su determinante fundamental, y sobre sus implicaciones clínicas.AbstractGravity was established as the determinant factor regarding differences in the distribution of ventilation and perfusion in the lung by John West, concept that continue to be exposed, up to day, as a basic principle of the lung physiology. The modern diagnostic images permit to demonstrate that gravity is not the determinant factor of these differences, a fact that generate big questions about concepts, among many others, support mechanical ventilations, ventilatory modes and one lung ventilation in lateral position during thoracic surgery. This article reflects on the recent findings of perfusion and ventilation studies that question the paradigm of gravity as its main determinant, and their clinical implications

Complementing mass customization toolkits with user communities: How peer input improves customer self-design

In this article, the authors propose that the canonical customer-toolkit dyad in mass customization (MC) should be complemented with user communities. Many companies in various industries have begun to offer their customers the opportunity to design their own products online. The companies provide web-based MC toolkits which allow customers who prefer individualized products to tailor items such as sneakers, PCs, cars, kitchens, cereals, or skis to their specific preferences. Most existing MC toolkits are based on the underlying concept of an isolated, dyadic interaction process between the individual customer and the MC toolkit. Information from external sources is not provided. As a result, most academic research on MC toolkits has focused on this dyadic perspective. The main premise of this article is that novice MC toolkit users in particular might largely benefit from information given by other customers. The pioneering research conducted by Jeppesen (2005), Jeppesen and Frederiksen (2006), and Jeppesen and Molin (2003) has shown that customers in the computer gaming and digital music instruments industries are willing to support each other for the sake of efficient toolkit use (e.g., how certain toolkit functions work). Expanding on their work, this article provides evidence that peer assistance appears also extremely useful in the two other major phases of the customer's individual self-design process, namely the development of an initial idea and the evaluation of a preliminary design solution. Two controlled experiments were conducted in which 191 subjects used an MC toolkit in order to design their own individual skis. The authors find that during the phase of developing an initial idea, having access to other users' designs as potential starting points stimulates the integration of existing solution chunks into the problem-solving process, which indicates more systematic problem-solving behavior. Peer customer input also turned out to have positive effects on the evaluation of preliminary design solutions. Providing other customers' opinions on interim design solutions stimulated favorable problem-solving behavior, namely the integration of external feedback. The use of these two problem-solving heuristics in turn leads to an improved process outcome, that is, self-designed products which meet the preferences of the customers more effectively (measured in terms of perceived preference fit, purchase intention, and willingness to pay). These findings have important theoretical and managerial implications. (author's abstract

The compression chord capacity model for the shear design and assessment of reinforced and prestressed concrete beams

This is the accepted version of the following article: [Cladera, A., Marí, A., Bairán, J. M., Ribas, C., Oller, E. and Duarte, N. (2016), The compression chord capacity model for the shear design and assessment of reinforced and prestressed concrete beams. Structural Concrete, 17: 1017–1032. doi:10.1002/suco.201500214], which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1002/suco.201500214/fullA simplified mechanical model is presented for the shear strength prediction of reinforced and prestressed concrete members with and without transverse reinforcement, with I, T or rectangular cross-section. The model, derived with further simplifications from a previous one developed by the authors, incorporates the contributions of the concrete compression chord, the cracked web, the dowel action and the shear reinforcement in a compact formulation. The mechanical character of the model provides valuable information about the physics of the problem and incorporates the most relevant parameters governing the shear strength of structural concrete members. The predictions of the model fit very well the experimental results collected in the ACI-DAfStb databases of shear tests on slender reinforced and prestressed concrete beams with and without stirrups. Due to this fact and the simplicity of the derived equations it may become a very useful tool for structural design and assessment in engineering practice.Peer ReviewedPostprint (author's final draft

Evaluation of Academic Competencies Through Standardized Instruments

The aim of this investigation is to assess the correlation among different competencies-assessment systems available on the market to measure social skills in the university environment. In order to carry out the research, three self-perception competency tests were used, and 30 competencies were evaluated in a Likert scale with several response levels: the LPA-Q, the ESCI-U, and the CompeUEM. The three questionnaires were completed by 57 university students. The results show a low degree of agreement among the different questionnaires in relation to measuring the same competencies, as well as an unclear factor structure

Proposal of an index to evaluate the ‘dewaterization’ of the urban water cycle and a practical application

Analyses of the relationship between water and energy do not account for the fact that the energy used in the urban water cycle is a consumer of water. To ensure the efficient use of water resources, the operator must know the raw water use associated with the energy input of the urban water infrastructure. The main contribution of this research is the proposal of an index that measures how much raw water is consumed by the energy used to produce 1 cubic m of water. The resulting index is a decision-making tool that enables the sustainable use of water resources. This article first explains the index, which is called the Water Footprint of the Urban Water Cycle. It then provides examples of how to apply the proposed method; among other applications, it can be used to establish a classification of energy sources based on their relative consumption of raw water, according to the electricity generation mix in each service area. The proposed method is useful for operators, policymakers and other stakeholders, enabling them to make decisions that contribute to the ‘dewaterization’ of the urban water cycle.European CommissionSpanish State Research AgencyRegional Government of AndalusiaEuropean Regional Development Fun

La predicción del desempeño académico de los estudiantes de ingeniería usando los resultados de la prueba icfes y datos demográficos

Introduction: This paper is part of a research project that aims to construct a predictive model for students’ academic performance, as result of an iterative process of experimentation and evaluation of the pertinence of some data mining techniques. Methodology: This paper was written in 2016 in the Universidad El Bosque, Bogotá, Colombia, and presents a comparative analysis of the performance and relevance of the J48 and Random Forest algorithms, in order to identify the most influential demographic and icfes score variables, as well as the classification rules, to predict the first year academic performance of the Engineering Faculty students, in Universidad El Bosque, Bogotá, Colombia. Results: The analysis process was carried out on 7,644 students’ records, and it was developed in two phases. Firstly, the data needed to feed the mining process was extracted and prepared. Secondly, the data mining process itself was implemented through preprocessing data and executing the classification algorithms available in Weka. Some significant variables and rules to predict academic performance are found, according to the studied population characteristics. Conclusions: The academic risk seen as the cause of the desertion phenomenon must be studied as a phenomenon itself. Establishing its causes facilitates the creation of preventive strategies for the accompaniment of students through their process, aimed to mitigate the risk of both phenomena.Introducción: este trabajo forma parte de un proyecto de investigación cuyo objetivo es construir un modelo predictivo para el rendimiento académico de los alumnos, como resultado de un proceso iterativo de experimentación y evaluación de la pertinencia de algunas técnicas de minería de datos.Metodología: este trabajo fue escrito en el 2016 en la Universidad El Bosque, Bogotá, Colombia y presenta un análisis comparativo del desempeño y relevancia de los algoritmos J48 y Random Forest para identificar las variables más influyentes, demográficas y de resultados del icfes, así como las reglas de clasificación, para predecir el desempeño académico del primer año de los estudiantes de la Facultad deIngeniería, en la Universidad El Bosque, Bogotá, Colombia. Resultados: el proceso de análisis se realizó con 7644 expedientes de estudiantes, y se desarrolló en dos fases. En primer lugar, se extrajeron y prepararon los datos necesarios para alimentar el proceso de minería de datos. En segundo lugar, se implementó el proceso de minería de datos mediante el pre-procesamiento de datos y la ejecución de los algoritmos de clasificación disponibles en Weka. Se hallaron algunas variables significativas y reglas para predecir el rendimiento académico, según las características de la población estudiada. Conclusiones: el riesgo académico, visto como la causa del fenómeno de deserción, debe ser estudiado como un fenómeno en sí mismo. Establecer sus orígenes facilita la creación de estrategias preventivas para el acompañamiento de los estudiantes durante su proceso, que mitiguen el riesgo de ambos fenómenos

Estandarización y documentación de los procesos operativos de la Empresa Montaind Ltda con base en los requistos de la Norma Iso 9001:2008

El presente trabajo, tiene como propósito estandarizar y documentar los procesos operativos de Montaind Ltda., con base en los requisitos de la norma NTC ISO 9001:2008. Para dar cumplimiento a este objetivo, se planteó una investigación cualitativa con un diseño descriptivo en la metodología. Montaind Ltda es una empresa del sector de montajes industriales, que se dedica a realizar montajes y mantenimiento metalmecánico en industrias papeleras, siderúrgicas y de alimentos. Inicialmente se presenta una breve descripción de la empresa. El trabajo se ha dividido en 3 capítulos, el primero que corresponde a la definición de los procesos y las directrices organizacionales, en donde se identifican los principios estratégicos y el mapa de procesos. En el segundo capítulo se presenta el desarrollo de la documentación de los procesos operativos, en donde se elabora la caracterización de los procesos, los procedimientos y formatos de acuerdo a los requisitos de la norma ISO 9001:2008, esperando que éstos faciliten una futura implementación del SGC diseñado en la empresa. El tercer capítulo corresponde al plan de sensibilización, el cual relaciona las actividades para promover una cultura de calidad en la prestación del servicio en la organización. Por último, este proyecto permite gestionar las operaciones de la cadena de valor para obtener un buen desempeño, asegurar que los procesos funcionen de manera integrada, ofrecer un producto satisfactorio para los clientes y organizar los procesos de la empresaPregradoIngeniero(a) Industria