451 research outputs found
The Association between Rheumatoid Arthritis and Type 2 Diabetes Mellitus
A research report from the Centers for Disease Control and Prevention (CDC) indicated that more than 50% of people with diabetes mellitus (DM) in the United States (U.S.) also have arthritis. The diabetes population is disproportionately affected by arthritis, but there has been limited and inconsistent research to confirm the association between type 2 diabetes mellitus (T2DM) and rheumatoid arthritis (RA). The current study aimed to identify an association between T2DM and RA for noninstitutionalized U.S. adults between 1999 and 2012 using a nationally representative sample from the National Health and Nutrition Examination Survey (NHANES) database (n =31,488 ). A quantitative, cross-sectional investigation was conducted to determine if patients with T2DM had an increased prevalence of RA. The current study also sought to identify characteristics that could affect the association between both groups and the prevalence of cardiovascular disease (CVD) in this population. Prevalence and adjusted odds ratios (OR) using logistic regression were calculated. The results show evidence of a strong association between T2DM and concomitant RA. Prevalence of RA was significantly higher in participants with T2DM compare to those without T2DM. Important factors in this association were gender, ethnicity, education, disability, and work functioning. The prevalence of CVD and adjusted OR of association were doubled in participants with T2DM and RA when compared to participants who had just one of the conditions; the OR of association was quadrupled when compared to those without this comorbidity. This study may provide patients and health care providers with a better understanding of the need for management of both conditions in a interdisciplinary manne
Dual refractive index and viscosity sensing using polymeric nanofibers optical structures
Porous materials have demonstrated to be ideal candidates for the creation of optical sensors with very high sensitivities. This is due both to the possibility of infiltrating the target substances into them and to their notable surface-to-volume ratio that provides a larger biosensing area. Among porous structures, polymeric nanofibers (NFs) layers fabricated by electrospinning have emerged as a very promising alternative for the creation of low-cost and easy-to-produce high performance optical sensors, for example, based on Fabry-Perot (FP) interferometers. However, the sensing performance of these polymeric NFs sensors is limited by the low refractive index contrast between the NFs porous structure and the target medium when performing in-liquid sensing experiments, which determines a very low amplitude of the FP interference fringes appearing in the spectrum. This problem has been solved with the deposition of a thin metal layer (∼ 3 nm) over the NFs sensing layer. We have successfully used these metal-coated FP NFs sensors to perform several real-time and in-flow refractive index sensing experiments. From these sensing experiments, we have also determined that the sponge-like structure of the NFs layer suffers an expansion/compression process that is dependent of the viscosity of the analyzed sample, what thus gives the possibility to perform a simultaneous dual sensing of refractive index and viscosity of a fluid
Low-Cost Piezoelectric Sensors for Time Domain Load Monitoring of Metallic Structures During Operational and Maintenance Processes
The versatility of piezoelectric sensors in measurement techniques and their performance in applications has given rise to an increased interest in their use for structural and manufacturing component monitoring. They enable wireless and sensor network solutions to be developed in order to directly integrate the sensors into machines, fixtures and tools. Piezoelectric sensors increasingly compete with strain-gauges due to their wide operational temperature range, load and strain sensing accuracy, low power consumption and low cost. This research sets out the use of piezoelectric sensors for real-time monitoring of mechanical strength in metallic structures in the ongoing operational control of machinery components. The behaviour of aluminium and steel structures under flexural strength was studied using piezoelectric sensors. Variations in structural behaviour and geometry were measured, and the load and μstrains during operational conditions were quantified in the time domain at a specific frequency. The lead zirconium titanate (PZT) sensors were able to distinguish between material types and thicknesses. Moreover, this work covers frequency selection and optimisation from 20 Hz to 300 kHz. Significant differences in terms of optimal operating frequencies and sensitivity were found in both structures. The influence of the PZT voltage applied was assessed to reduce power consumption without signal loss, and calibration to μstrains and loads was performed.This research was funded by Basque Government, grant number KK-2019/00051-SMARTRESNAK and
by the European Commission, grant number 869884- RECLAIM
Neural heterogeneity promotes robust learning
The brain has a hugely diverse, heterogeneous structure. Whether or not heterogeneity at the neural level plays a functional role remains unclear, and has been relatively little explored in models which are often highly homogeneous. We compared the performance of spiking neural networks trained to carry out tasks of real-world difficulty, with varying degrees of heterogeneity, and found that it substantially improved task performance. Learning was more stable and robust, particularly for tasks with a rich temporal structure. In addition, the distribution of neuronal parameters in the trained networks closely matches those observed experimentally. We suggest that the heterogeneity observed in the brain may be more than just the byproduct of noisy processes, but rather may serve an active and important role in allowing animals to learn in changing environments. Summary Neural heterogeneity is metabolically efficient for learning, and optimal parameter distribution matches experimental data
Resistencia a la compresión de un concreto f´c=210kg/cm2, sustituyendo el cemento por 10% de ceniza de tusa de maíz y 5% de ceniza de cola de caballo
En esta investigación se ha determinado la influencia en la resistencia a compresión del concreto f´c = 210 kg/cm2 usando agregados de la cantera de "Medina" y sustituyendo el cemento por 10% de ceniza de tusa de maíz y 5% de ceniza de cola de caballo.
La metodología cuasi-experimental de la investigación consistió preparar mezclas de concreto para una resistencia a la compresión de 210 kg/cm2, tomando 9 muestras de probetas patrón y otras 9 con la sustitución al cemento, para posteriormente evaluarlas en su resistencia a la compresión al concreto pasado los 7, 14 y 28 días.
Los resultados obtenidos al incorporar el 10% de ceniza de tusa de maíz y 5 % de ceniza de cola de caballo al diseño experimental, llegaron con una resistencia a la compresión de 246.55 kg/cm2 a los 28 días de curado; resistencia muy optima a la que se quiso llegar, superando a las probetas hechos con el diseño patrón de resistencia a la compresión de 223.26 kg/cm2, siendo un 10.92% mayor las probetas experimentales a los 28 días. La resistencia de las probetas a los 14 días de curado llegó a superar en un 9.76%, mientras que a los 7 días de curado de las probetas experimentales disminuyo en 1.72% con respecto a las probetas patrón.
Concluyendo que los resultados obtenidos nos indican que los concretos incorporados con sustitución al cemento por cenizas de 10% tusa de maíz y 5% cola de caballo presentan una resistencia mayor a las del concreto convencional ensayadas a los 7, 14 y 28 días.Tesi
Servitization and business models in project‐based firms: the case of energy efficient architecture
Purpose:In the context of energy-efficient buildings, technological innovation and the particularities of design, installations, maintenance and use are presented as an
ideal framework for studying
the introduction of the phenomenon of servitization into the business models
of project‐based firms (PBFs).
In this article, we attempt to evaluate how servitization gains a
leading role in existing business models in this area
On Mechanical and Electrical Coupling Determination at Piezoelectric Harvester by Customized Algorithm Modeling and Measurable Properties
Piezoelectric harvesters use the actuation potential of the piezoelectric material to transform mechanical and vibrational energies into electrical power, scavenging energy from their environment. Few research has been focused on the development and understanding of the piezoelectric harvesters from the material themselves and the real piezoelectric and mechanical properties of the harvester. In the present work, the authors propose a behavior real model based on the experimentally measured electromechanical parameters of a homemade PZT bimorph harvester with the aim to predict its Vrms output. To adjust the harvester behavior, an iterative customized algorithm has been developed in order to adapt the electromechanical coupling coefficient, finding the relationship between the harvester actuator and generator behavior. It has been demonstrated that the harvester adapts its elongation and its piezoelectric coefficients combining the effect of the applied mechanical strain and the electrical behavior as a more realistic behavior due to the electromechanical nature of the material. The complex rms voltage output of the homemade bimorph harvester in the frequency domain has been successfully reproduced by the proposed model. The Behavior Real Model, BRM, developed could become a powerful tool for the design and manufacturing of a piezoelectric harvester based on its customized dimensions, configuration, and the piezoelectric properties of the smart materials.This research was funded by the Basque Government, grant number KK-2021/00082-µ4IIoT,
and by the European Commission, grant number 869884- RECLAIM
Balanced Islands in Two Colored Point Sets in the Plane
Let be a set of points in general position in the plane, of which
are red and of which are blue. In this paper we prove that there exist: for
every , a convex set containing
exactly red points and exactly
blue points of ; a convex set containing exactly red points and exactly blue points of . Furthermore, we present
polynomial time algorithms to find these convex sets. In the first case we
provide an time algorithm and an time algorithm in the
second case. Finally, if is
small, that is, not much larger than , we improve the running
time to
Technological capabilities, resilience capabilities and organizational effectiveness
© 2016, © 2016 Informa UK Limited, trading as Taylor & Francis Group. Previous research has defined resilience as a desirable characteristic for an organization and its members to possess when circumstances adversely change. Resilience is analysed through different perspectives as organizational responses to external threats, organizational reliability or employee strengths. However, the role of resilience in enhancing organizational effectiveness is not fully understood. Grounded in organizational ambidexterity, the current research tests the value of resilience capabilities developed through specific Human Resource Practices (HRPs) in the context of ever-changing market conditions. This paper argues that as well as technological capabilities, HRPs that build resilience within an organization are needed to successfully implement technological change. Resilience capabilities are a mediating factor between technological capabilities and organizational effectiveness, whilst environment dynamism and competitive intensity are moderators of this relationship. Using a primary sample of 205 manufacturing firms, a model is presented and tested using Structural Equation Modelling. The results reinforce the importance of HRPs in building resilience which helps firms to continuously adjust to change and subsequently enhance their organizational effectiveness
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