Coating of Felt Fibers with Carbon Nanotubes and PEDOT with Different Counterions: Temperature and Electrical Field Effects.

The use of wearable devices has promoted new ways of integrating these devices, one of which is through the development of smart textiles. Smart textiles must possess the mechanical and electrical properties necessary for their functionality. This study explores the impact of polymer-felt microstructure variations on their morphology, electrical, and mechanical properties. The application of thermal treatment, along with an electric field, leads to a substantial structural reorganization of the molecular chains within pristine felt. This results in a system of nanofibrils coated with MWCNT-PEDOT, characterized by highly ordered counterions that facilitate the flow of charge carriers. Both temperature and an electric field induce reversible microstructural changes in pristine felt and irreversible changes in coated felt samples. Furthermore, electropolymerization of PEDOT significantly enhances electrical conductivity, with PEDOT:BTFMSI-coated fabric exhibiting the highest conductivity

Analysis of adiabatic heating and its influence on the Garofalo equation parameters of a high nitrogen steel

Torsion tests at high temperatures and high strain rates were conducted on a high nitrogen steel (HNS). Under these conditions, adiabatic heating influences its flow behavior. This work focus on a new algorithm for conducting the adiabatic heating correction of stress-strain curves. The algorithm obtains the stress-strain curves at quasiisothermal conditions from those at adiabatic conditions. The corrections in stress obtained can be higher than 15% and increase with increasing strain rates and decreasing temperatures. On the other hand, an upper bound for the temperature rise was found using a dynamic material behavior approach. Finally, the influence of adiabatic heating correction on the Garofalo equation parameters of HNS was analyzed. High values of activation energy and stress exponent were attributed to reinforcement by dispersed carbonitrides and the high amount of alloying elements.The work was carried out through the Projects PBC-05-010-1 from JCCM (Castilla- La Mancha, Spain) and MAT2006-13348 from CICYT. Thanks are given to Prof. E Evangelista for valuable assistance.Peer reviewe

Building Urban Resilience: A Dynamic Process Composition Approach

Urban resilience (also referred to as city resilience) has become a strategic goal of city administrators. Given the diversity of threats and city contexts, managing urban resilience is a complex task that has been conceptualized as a process by the so-called urban resilience frameworks proposed during the last decade. But conceptualization is not enough: an urban resilience building process may last for months, even years, and needs to coordinate many different actors using different tools. Therefore, some type of tool support is required for process control. In this paper, we introduce a proposal for the operationalization of urban resilience processes based on the notion of process family. The notion of family allows to deal with the natural diversity of urban resilience, and its transformation into a process specification allows the enactment, monitoring and measuring of the process. We have applied our approach to the well-known Smart Mature Resilience framework

Monitoring molecular dynamics of bacterial cellulose composites reinforced with graphene oxide by carboxymethyl cellulose addition

[EN] Broadband Dielectric Relaxation Spectroscopy was performed to study the molecular dynamics of dried Bacterial Cellulose/Carboxymethyl Cellulose-Graphene Oxide (BC/CMC-GO) composites as a function of the concentration of CMC in the culture media. At low temperature the dielectric spectra are dominated by a dipolar process labelled as a beta -relaxation, whereas electrode polarization and the contribution of dc-conductivity dominate the spectra at high temperatures and low frequency. The CMC concentration affects the morphological structure of cellulose and subsequently alters its physical properties. X-ray diffractometry measurements show that increasing the concentration of CMC promotes a decrease of the Ia/Ib ratio. This structural change in BC, that involves a variation in inter- and intramolecular interactions (hydrogen-bonding interactions), affects steeply their molecular dynamics. So, an increase of CMC concentration produces a significantly decrease of the -relaxation strength and an increase of the dc-conductivity.This work was supported by the DGCYT [MAT2015-63955-R]; the Vice-Rectorate for Research of the Pontificia Universidad Catolica del Peril and the National Council of Science, Technology and Technological Innovation of Peru (CONCYTEC/FONDECYT).Sanchis Sánchez, MJ.; Carsí Rosique, M.; Gomez, CM.; Culebras, M.; Gonzales, K.; Gisbert Torres, F. (2017). Monitoring molecular dynamics of bacterial cellulose composites reinforced with graphene oxide by carboxymethyl cellulose addition. Carbohydrate Polymers. 157:353-360. https://doi.org/10.1016/j.carbpol.2016.10.00135336015

Effect of Chitin Whiskers on the Molecular Dynamics of Carrageenan-Based Nanocomposites

[EN] Films of carrageenan (KC) and glycerol (g) with different contents of chitin nanowhiskers (CHW) were prepared by a solution casting process. The molecular dynamics of pure carrageenan (KC), carrageenan/glycerol (KCg) and KCg with different quantities of CHWs as a filler was studied using dielectric relaxation spectroscopy. The analysis of the CHW effect on the molecular mobility at the glass transition, T-g, indicates that non-attractive intermolecular interactions between KCg and CHW occur. The fragility index increased upon CHW incorporation, due to a reduction in the polymer chains mobility produced by the CHW confinement of the KCg network. The apparent activation energy associated with the relaxation dynamics of the chains at T-g slightly increased with the CHW content. The filler nature effect, CHW or montmorillonite (MMT), on the dynamic mobility of the composites was analyzed by comparing the dynamic behavior of both carrageenan-based composites (KCg/xCHW, KCg/xMMT).This research was funded by the DGCYT grant number [MAT2015-63955-R] and the Vice-Rectorate for Research of the Pontificia Universidad Catolica del Peru and the the Peruvian Science and Technology Program (INNOVATE-PERU) And The APC was funded by MDPI.Carsí Rosique, M.; Sanchis Sánchez, MJ.; Gómez, CM.; Rodriguez, S.; García-Torres, F. (2019). Effect of Chitin Whiskers on the Molecular Dynamics of Carrageenan-Based Nanocomposites. Polymers. 11(6):1-16. https://doi.org/10.3390/polym11061083116116Zheng, Y., Monty, J., & Linhardt, R. J. (2015). Polysaccharide-based nanocomposites and their applications. Carbohydrate Research, 405, 23-32. doi:10.1016/j.carres.2014.07.016Jamróz, E., Kulawik, P., & Kopel, P. (2019). 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Osteotomías distales de los metatarsianos menores realizadas por cirugía abierta vs cirugía percutánea en el tratamiento de las metatarsalgias.

Objetivo. Comparar los resultados clínicos y radiológicos de las osteotomías distales de los metatarsianos menores realizadas por cirugía abierta y por cirugía percutánea en el tratamiento de las metatarsalgias Material y método. Revisión retrospectiva de 44 metatarsalgias: 22 en cada grupo. Recogida de datos epidemiológicos, clínicos y medición de parámetros radiográficos. Resultados. Se consiguieron modificaciones en los parámetros radiográficos con ambas técnicas, con mayor corrección con la cirugía abierta. Las fórmulas metatarsales postoperatorias continuaron siendo no armónicas en ambos grupos. Todos los pacientes mejoraron clínicamente. La cirugía abierta tuvo más complicaciones. Conclusiones. Los resultados clínicos y radiológicos de las osteotomías percutáneas son similares a los obtenidos por cirugía abierta, pero con menos complicaciones. La obtención de una fórmula metatarsal armónica no debería ser el objetivo principal de la cirugía de las metatarsalgias, ya que, según nuestro estudio, no es una condición indispensable para lograr un buen resultado clínicoObjectives. To compare the radiographic and functional outcomes in lesser metatarsal distal osteotomies performed by percutaneous and open surgery for the treatment of metatarsalgia. Methods. A retrospective medical record review of 44 cases of discharge diagnosis of metatarsalgia: 22 patients in each group. Epidemiological data, clinical data and radiological measurements were collected. Results . Improvement of radiological parameters were obtained with both techniques, with better correction with open than with percutaneous surgery. Postoperatively metatarsal parabola continues being nonharmonious in both groups. All patients improved in clinical assessment. Open surgery had more complications than percutaneous surgery. Conclusions . Clinical and radiological outcomes of lesser metatarsal distal osteotomies performed percutaneously are similar to those obtained by open surgery, but with fewer complications. To obtain a harmonic metatarsal parabola should not be the main purpose of surgery of metatarsalgia because it is not an essential condition to achieve a good clinical outcome

Hallux Rigidus de grado medio : nuestra técnica quirúrgica de elección

Hallux rigidus is the result of a degenerative process of the metatarsophalangeal joint of the hallux. In the intermediate stages there are controversies in the type of treatments and different types of osteotomies can be performed. Objective. To analyze cases of moderate grade hallux rigidus that have undergone surgery at out center with a chevron-type modified osteotomy. Material and methods. We conducted a retrospective study between January 2013 and December 2015 of 21 hallux rigidus with a minimum follow-up of 12 months. To evaluate the results we used the AOFAS questionnaire and the visual analogue scale (VAS). At the end of the follow-up we also conducted a satisfaction questionnaire. Results. The postoperative results show a considerable increase in the average mean of the AOFAS questionnaire from 61,3 before surgery to 92,1 at 12 months after surgery. The VAS improved 6 points and 18 patients were very satisfied with the results. There were no cases of nonunion, avascular necrosis, MTF stiffness, failed implants or infection. No patient was reoperated. Conclusion. We believe that our technique can be useful nowadays. This technique is easy to perform and reproducibl