Sustainable supply chain management: The influence of disposal scenarios on the environmental impact of a 2400 L waste container

This paper analyzes the influence of the supply chain management on the environmental impact of a 2400 L waste disposal container used in most cities of Spain. The studied functional unit, a waste disposal container, made up mostly of plastic materials and a metallic structure, and manufactured in Madrid (Spain), is distributed to several cities at an average distance of 392 km. A life cycle assessment of four different scenarios (SC) has been calculated with the software EcoTool v4.0 (version 4.0; i+: Zaragoza, Spain, 2015) and using Ecoinvent v3.0 database (version 3.0; Swiss Centre for Life Cycle Inventories: St. Gallen, Switzerland, 2013). The environmental impact has been characterized with two different methodologies, recipe and carbon footprint. In order to reduce the environmental impact, several end of life scenarios have been performed, analyzing the influence of the supply chain on a closed-looped system that increases recycling. Closed loop management of the waste and reuse of parts allows companies to stop selling products and start selling the service that their products give to the consumers

Life cycle assessment of a plastic part injected with recycled Polypropylene: a comparison with alternative virgin materials

Plastics recycling is becoming a common action to reduce our products and processes'' environmental impact, and it is of the utmost importance to introduce circular economy strategies. However, for most of the different types of thermoplastics, recycling is not currently its usual end of life due to the technical difficulties in the sorting and recycling processes. This paper presents the complete life cycle assessment of an industrial component made with three different thermoplastics; two virgin thermoplastics typically used for similar parts in the market as Polyamide 6 and Polypropylene, and an alternative source of 100% recycled Polypropylene. All life cycle stages are included in the study. After carrying out the life cycle inventory, calculations of the environmental impact of each life cycle steps have been performed with ReCiPe 2016 EndPoint (H/A) v1.03/World and with IPCC 2013 GWP 100a v1.03 methodologies, comparing all three materials under the same conditions. A sensibility assessment has also been performed, calculating a worst-case scenario of the recycled material, and considering higher material acquisition distances. This study shows that recycled Polypropylene contributes to reducing the overall environmental impact of the component life cycle by 29.8% under ReCiPe, and by 42.8% under Carbon Footprint when compared to virgin Polypropylene. For the worst-case scenario, these reductions in the environmental impact of the component life cycle are also significant: 23.2% and 36.4%, respectively, showing that the use of recycled polymers is a key approach to reduce the environmental impact of plastic components

Study on the socio-economic impact of cancer disease on cancer patients and their relatives

Cancer is one of the most relevant social and health problems in the world. The disease entails additional costs for cancer patients and their families that are not covered by the public part of our welfare state, and which they assume themselves simply because they are ill. The main objective of this study is to identify and analyse the additional cost and socioeconomic impact of cancer disease on patients diagnosed with cancer disease and their families. Methods: Descriptive cross-sectional randomised observational epidemiological study without replacement with prevalence of cancer disease in the study base, carried out in the Medical Oncology Service of the Complejo Asistencial Universitario de Salamanca (CAUSA), Spain. Results: The study variable has been the additional cost of the cancer disease for cancer patients and their families that is not covered by our autonomous health system. Conclusions: Cancer disease entails an additional cost for the patient and family; more specifically, for 55% of the patients in the study sample, the diagnosis of cancer represents extra expenditure of between 8.38–9.67% of their annual income. Furthermore, the disability and dependence of patients does not represent an additional cost due to their levels of functionality, but it can have repercussions on the future cost of the evolution of the disease, in addition to the fact of having cancer

Study of chemotherapy-induced cognitive impairment in women with breast cancer

Oncology patients experience a large number of symptoms and, those referring to cognitive performance has an ever-increasing importance in clinical practice, due to the increase in survival rates and interest in the patient’s quality of life. The studies reviewed showed that chemotherapy-related cognitive impairmentmight occur in 15 and 50% of oncology patients. The main objective of this research was to study the impact of chemotherapy on the cognitive function of patients with locoregional breast cancer. Method: Analytical, prospective, longitudinal study using three measures, unifactorial intrasubject design, non-probability, and random selection sampling. The sample comprisedwomen newly diagnosedwith locoregional breast cancer in stages I, II, IIIA who received chemotherapy at the University Hospital of Salamanca (Complejo Asistencial Universitario de Salamanca), randomly selected for three years. Semi-structured interviews were conducted, and anxiety and depression (Hospital Anxiety and Depression scale, HAD); quality of life (QLQ-BR23 scale) and the following cognitive variables were assessed—processing speed, attention, memory, and executive functions (subtests of theWechsler Intelligence Scale and the TrailMaking Test). Results: The final sample size included 151 participants; 23 were excluded. A decline in cognitive performance was observed in patients, which did not completely recover two months after chemotherapy was completed. Additionally, worse cognitive performance was observed in patients with anxious or depressive symptoms. There was a negative impact on the quality of life. Conclusion: Chemotherapy had an impact on the cognitive performance of oncology patients in most cognitive domains studied

Implementación de un modelo de interacción Responseware en Grados de Ciencias de la Salud

Memoria ID-0164. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2017-2018

Elliptical Halbach magnet and gradient modules for low-field portable MRI

Objective. To develop methods to design the complete magnetic system for a truly portable MRI scanner for neurological and musculoskeletal (MSK) applications, optimized for field homogeneity, field of view (FoV) and gradient performance compared to existing low-weight configurations. Approach. We explore optimal elliptic-bore Halbach configurations based on discrete arrays of permanent magnets. In this way, we seek to improve the field homogeneity and remove constraints to the extent of the gradient coils typical of Halbach magnets. Specifically, we have optimized a tightly-packed distribution of magnetic Nd$_2$Fe$_14$B cubes with differential evolution algorithms, and a second array of shimming magnets with interior point and differential evolution methods. We have also designed and constructed an elliptical set of gradient coils that extend over the whole magnet length, maximizing the distance between the lobe centers. These are optimized with a target field method minimizing a cost function that considers also heat dissipation. Main result. We have employed the new toolbox to build the main magnet and gradient modules for a portable MRI scanner designed for point-of-care and residential use. The elliptical Halbach bore has semi-axes of 10 & 14 cm and the magnet generates a field of 87 mT homogeneous down to 5,700 ppm (parts per million) in a 20 cm diameter FoV, it weighs 216 kg and has a width of 65 cm and a height of 72 cm. Gradient efficiencies go up to around 0.8 mT/m/A, for a maximum of 12 mT/m with in 0.5 ms with 15 A & 15 V amplifier. The distance between lobes is 28 cm, significantly increased with respect to other Halbach-based scanners. Heat dissipation is around 25 W at maximum power, and gradient deviations from linearity are below 20% in a 20 cm sphere

Evaluación del impacto ambiental del proceso de reciclado de materiales plásticos.

El consumo de plástico a nivel mundial ha sufrido un aumento continuo desde la invención del mismo. Laflexibilidad que ofrece en cuanto a propiedades físicas, métodos de fabricación o coste lo convierten enuno de los materiales más útiles y flexibles a la hora de diseñar productos. Sin embargo, en las últimasdécadas el uso excesivo y el inadecuado tratamiento tras su fase de uso nos ha hecho enfrentarnos alproblema de la gestión de estos residuos.A la vez que el volumen de plástico acumulado en el mundo aumentaba, también lo ha hecho la concienciamedioambiental de la sociedad. Se ha promovido un cambio en el modelo económico y social que obligaa las empresas a hacer frente al reto de generar menos residuos y gestionar de la manera más eficienteposible los generados.El aspecto medioambiental llegó al diseño de producto con una metodología que buscaba disminuir elimpacto ambiental de los productos desde la misma fase de concepción de los mismos. El conocido como“Ecodiseño” propone adicionalmente, mediante diferentes enfoques, la valoración del impacto ambientalcomo un factor más sobre el que se puede influir en la fase de diseño. Algunos de estos enfoques pasanpor seleccionar materiales y procesos de fabricación con cargas ambientales menores a otras alternativasy seleccionar métodos de unión entre componentes que permitan una rápida y fácil separación yreciclabilidad.Esta tesis se centra en la evaluación ambiental del plástico reciclado y en el análisis de viabilidad de su usopara procesos industriales. El impacto ambiental se ha analizado de forma comparativa para una mismaunidad funcional que puede ser fabricada en distintos materiales de origen virgen y un material reciclado,de forma más concreta, buena parte de la tesis doctoral se ha centrado en el estudio de una pieza deplástico utilizada en encimeras de inducción cuyo principal objeto es el alojamiento de placas electrónicasy la gestión del cableado interno del aparato. El resultado, publicado en el artículo “Life Cycle Assessmentof a Plastic Part Injected with Recycled Polypropylene. A Comparison with Alternative Virgin Materials”,muestra la reducción del impacto desglosada en las diferentes etapas del ciclo de vida del producto. Elanálisis parte de la descomposición del proceso completo en fases y el estudio de todos los procesosllevados a cabo para recuperar desechos post-industriales de plástico. Este proceso se realiza hasta laobtención de material reciclado, cuyas características físicas son equiparables, según los resultados de lainvestigación, a las de materiales vírgenes.Esta reducción supone el 30% del impacto, según la metodología ReCiPe, para el caso de la sustitucióndirecta de un material virgen por otro reciclado. Se debe principalmente al descenso de los impactosasociados a la fabricación de la materia prima. Se puede afirmar, por tanto, que en un escenario en el quetécnicamente sea viable el uso de materiales reciclados, se obtendrá un mayor ahorro medioambiental alsustituir dichos materiales vírgenes por su correspondiente alternativa de fuentes recicladas.El análisis de las propiedades mecánicas del material reciclado comienza con la realización de unasimulación del proceso de inyección comparativa entre ambas fuentes de material para una pieza deplástico utilizado como soporte de electrónica y gestión de cableado en encimeras de inducción del grupoBSH. Para la caracterización de las propiedades mecánicas del material se requerían muestras inyectadascon dicho material en un molde ya existente. Para asegurar la factibilidad, se realizó una caracterizaciónreológica y posteriormente una simulación del proceso de inyección. El análisis de la granza demuestrauna mayor viscosidad en el material reciclado que, sin embargo, no afecta de forma considerable alproceso de moldeo por inyección. Los resultados fueron presentados en el 30º Congreso Europeo deModelado y Simulación (EMSS) de 2018 en Budapest, con el artículo titulado: “PROCESSABILITY ANALYSISOF AN INJECTED PART IN VIRGIN OR RECYCLED POLYPROPYLENE”Debido al origen post-industrial de los desechos y al proceso de reciclaje mecánico sufrido para llegar asu nuevo estado, el material reciclado sufre una serie de daños en su estructura interna, como elacortamiento de sus cadenas poliméricas, que pueden alterar, entre otros aspectos, su comportamientodimensional en piezas inyectadas o bien generar alabeos o deformaciones debido a las tensiones internas.En el artículo “Dimensional Stability and Process Capability of an Industrial Component Injected withRecycled Polypropylene” se analizan las variaciones dimensionales sufridas por un componente inyectadoen material reciclado sometido a diferentes ensayos térmicos y comparados con el material original. Secomprueba el efecto del aumento de viscosidad observado en el material reciclado, generando mayorcantidad de tensiones internas en la pieza analizada. Estas tensiones, liberadas ante la aportación deenergía en el calentamiento a diferentes temperaturas, provocan alteraciones dimensionales distintas enpiezas de diferentes materias primas. Esto se ve agravado por la geometría de la pieza por la que seobserva el efecto de la menor rigidez del material reciclado. La mayor contracción se obtiene en lasdimensiones afectadas por geometrías menos rígidas. Sin embargo, la variación dimensional, si bientiende a ser mayor en material reciclado, no es significativa a efectos prácticos, por lo que se hadeterminado viable la utilización de estos materiales para la pieza estudiada.También se realiza un estudio de la estabilidad del proceso de inyección para ambos materiales. Elresultado arroja la viabilidad de utilizar materiales reciclados, obteniendo parámetros aceptables de losvalores de Cp y Cpk en todos los casos. Sin embargo, sí se muestra una mayor variabilidad en las medidasobtenidas en materiales reciclados, estando los resultados de las muestras analizadas en material virgen,comprendidos en un rango de medidas menor.Por último, se analizan las propiedades mecánicas en base a muestras obtenidas a partir de piezasinyectadas en ambos materiales. De nuevo se analizan las propiedades consideradas de mayor interés(tensión de fluencia y módulo elástico) a tres diferentes temperaturas: temperatura ambiente, 50ºC y80ºC Estas temperaturas de análisis se han seleccionado por considerarse situaciones reales durante suetapa de almacenamiento previo a su ensamblaje, y en su etapa de uso.El resultado de éste análisis muestra una pérdida de propiedades del 22% del módulo elástico en elmaterial reciclado con respecto al material virgen y de ambos con respecto a sus fichas técnicas. Estadisminución, sin embargo, tiende a igualarse cuando el material se encuentra a temperaturas mayores,siendo el límite elástico in 13% mayor para el material virgen a 50º y de nuevo un 11% menor con respectoal material virgen a 80ºC.Por tanto, con que esta tesis doctoral se ha logrado evaluar la viabilidad técnica y ambiental del uso dematerial reciclado. Los resultados obtenidos han servido para introducir un PP reciclado en la producciónde encimeras de inducción.<br /

Prepolarized MRI of Hard Tissues and Solid-State Matter

[EN] Prepolarized MRI (PMRI) is a long-established technique conceived to counteract the loss in signal-to-noise ratio (SNR) inherent to low-field MRI systems. When it comes to hard biological tissues and solid-state matter, PMRI is severely restricted by their ultra-short characteristic relaxation times. Here we demonstrate that efficient hard-tissue prepolarization is within reach with a special-purpose 0.26 T scanner designed for ex vivo dental MRI and equipped with suitable high-power electronics. We have characterized the performance of a 0.5 T prepolarizer module, which can be switched on and off in 200 mu s. To this end, we have used resin, dental and bone samples, all with T1$${\mathbf{T}}_{\mathbf{1}}$$ times of the order of 20 ms at our field strength. The measured SNR enhancement is in good agreement with a simple theoretical model, and deviations in extreme regimes can be attributed to mechanical vibrations due to the magnetic interaction between the prepolarization and main magnets.Agencia Valenciana de la Innovaci~o; European Regional Development Fund; Ministerio de Ciencia e Innovacion; This work was supported by the Ministerio de Ciencia e Innovaci~on of Spain through research grant PID2019-111436RBC21. Action co-financed by the European Union through the Programa Operativo del Fondo Europeo de Desarrollo Regional (FEDER) of the Comunitat Valenciana 2014-2020 (IDIFEDER/2018/022). JMG and JB acknowledge support from the Innodocto program of the Agencia Valenciana de la Innovacion (INNTA3/2020/22 and INNTA3/2021/17); Ministerio de Ciencia e Innovaci~on of Spain, Grant/Award Number: PID2019-111436RB-C21; Programa Operativo del Fondo Europeo de Desarrollo Regional (FEDER) of the Comunitat Valenciana, Grant/Award Number: IDIFEDER/2018/022; Innodocto program of the Agencia Valenciana de la Innovacion, Grant/Award Numbers: INNTA3/2020/22, INNTA3/2021/17Borreguero-Morata, J.; González Hernández, JM.; Pallás Lodeiro, E.; Rigla, JP.; Algarín-Guisado, JM.; Bosch-Esteve, R.; Galve, F.... (2022). Prepolarized MRI of Hard Tissues and Solid-State Matter. NMR in Biomedicine. 35(8):1-10. https://doi.org/10.1002/nbm.473711035

Simultaneous imaging of hard and soft biological tissues in a low-field dental MRI scanner

[EN] Magnetic Resonance Imaging (MRI) of hard biological tissues is challenging due to the fleeting lifetime and low strength of their response to resonant stimuli, especially at low magnetic fields. Consequently, the impact of MRI on some medical applications, such as dentistry, continues to be limited. Here, we present three-dimensional reconstructions of ex-vivo human teeth, as well as a rabbit head and part of a cow femur, all obtained at a field strength of 260 mT. These images are the first featuring soft and hard tissues simultaneously at sub-Tesla fields, and they have been acquired in a home-made, special-purpose, pre-medical MRI scanner designed with the goal of demonstrating dental imaging at low field settings. We encode spatial information with two pulse sequences: Pointwise-Encoding Time reduction with Radial Acquisition and a new sequence we have called Double Radial Non-Stop Spin Echo, which we find to perform better than the former. For image reconstruction we employ Algebraic Reconstruction Techniques (ART) as well as standard Fourier methods. An analysis of the resulting images shows that ART reconstructions exhibit a higher signal-to-noise ratio with a more homogeneous noise distribution.We thank anonymous donors for their tooth samples, Andrew Webb and Thomas O'Reilly (LUMC) for discussions on hardware and pulse sequences, and Antonio Tristan (UVa) for information on reconstruction techniques. This work was supported by the European Commission under Grants 737180 (FET-OPEN: HISTO-MRI) and 481 (ATTRACT: DentMRI). Action co-financed by the European Union through the Programa Operativo del Fondo Europeo de Desarrollo Regional (FEDER) of the Comunitat Valenciana 2014-2020 (IDIFEDER/2018/022). Santiago Aja-Fernandez acknowledges Ministerio de Ciencia e Innovacion of Spain for research grant RTI2018-094569-B-I00.Algarín-Guisado, JM.; Díaz-Caballero, E.; Borreguero-Morata, J.; Galve, F.; Grau-Ruiz, D.; Rigla, JP.; Bosch-Esteve, R.... (2020). Simultaneous imaging of hard and soft biological tissues in a low-field dental MRI scanner. Scientific Reports. 10(1):1-14. https://doi.org/10.1038/s41598-020-78456-2S114101Haacke, E. M. et al. Magnetic Resonance Imaging: Physical Principles and Sequence Design Vol. 82 (Wiley-liss, New York, 1999).Bercovich, E. & Javitt, M. C. Medical imaging: from roentgen to the digital revolution, and beyond. Rambam Maimonides Med. J. 9, e0034. https://doi.org/10.5041/rmmj.10355 (2018).Mastrogiacomo, S., Dou, W., Jansen, J. A. & Walboomers, X. F. Magnetic resonance imaging of hard tissues and hard tissue engineered bio-substitutes. Mol. Imag. Biol. 21, 1003–1019. https://doi.org/10.1007/s11307-019-01345-2 (2019).Duer, M. J. 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A Fast 0.5 T Prepolarizer Module for Preclinical Magnetic Resonance Imaging

We present a magnet and high power electronics for Prepolarized Magnetic Resonance Imaging (PMRI) in a home-made, special-purpose preclinical system designed for simultaneous visualization of hard and soft biological tissues. The sensitivity of MRI systems grows with field strength, but so do their costs. PMRI can boost the signal-to-noise ratio (SNR) in affordable low-field scanners by means of a long and strong magnetic pulse. However, this must be rapidly switched off prior to the imaging pulse sequence, in timescales shorter than the spin relaxation (or T1) time of the sample. We have operated our prepolarizer at up to 0.5 T and demonstrated enhanced magnetization, image SNR and tissue contrast with PMRI of tap water, an ex vivo mouse brain and food samples. These have T1 times ranging from hundreds of milli-seconds to single seconds, while the preliminary high-power electronics setup employed in this work can switch off the prepolarization field in tens of milli-seconds. In order to make this system suitable for solid-state matter and hard tissues, which feature T1 times as short as 10 ms, we are developing new electronics which can cut switching times to ~ 300 μs. This does not require changes in the prepolarizer module, opening the door to the first experimental demonstration of PMRI on hard biological tissues