Ingeniería básica de planta desaladora de agua de mar de 40.000 m3 /día de capacidad

Barbados está clasificado por la Comisión de las Naciones Unidas sobre el Agua como un país con "escasez de agua", poniéndolo sólo ligeramente por delante de las naciones del desierto de Oriente Medio en términos de disponibilidad per cápita. En 2015, la Barbados Water Authority abrió un concurso para la realización de un proyecto de dos plantas desaladoras con una producción unitaria de 30.000 m3/día de agua potable. En este proyecto se realiza el diseño de una planta desaladora con una capacidad de producción de hasta 40.000 m3/día de agua potable, con el fin de tener una capacidad adicional a la requerida para poder realizar mantenimiento mientras que la planta sigue produciendo a la capacidad necesaria de 30.000 m3/día.Universidad de Sevilla. Grado en Ingeniería Químic

Planta de producción de fosfato monocálcico y fosfato dicálcico

En este proyecto se desarrolla la ingeniería básica del proceso de producción de fosfato monocálcico (MCP) y fosfato dicálcico (DCP) para alimentación animal. Para ello, se estudia el proceso de producción más empleado en la industria y se desarrolla el proyecto para una producción anual total de 60.000Tn de MCP y DCP, de forma que se minimicen los consumibles y se maximice la eficiencia del proceso. La planta operará 24h al día durante 300 días al año, y el producto generado será almacenado para su posterior venta a granel en camión o big bags.In this project, the basic engineering of the production process of monocalcium phosphate (MCP) and dicalcium phosphate (DCP) for animal feed is developed. For this, the production process most used in the industry is studied and the project is developed for a total annual production of 60,000Tn of MCP and DCP, so that consumables are minimized and process efficiency is maximized. The plant will operate 24 hours a day for 300 days per year, and the generated product will be stored for later sale in bulk by truck or big bags.Universidad de Sevilla. Máster Universitario en Ingeniería Químic

Overcoming the Challenge of Producing Large and Flat Nanocellular Polymers: A Study with PMMA

Although nanocellular polymers are interesting materials with improved properties in comparison with conventional or microcellular polymers, the production of large and flat parts of those materials is still challenging. Herein, gas dissolution foaming process is used to produce large and flat nanocellular polymethylmethacrylate samples. In order to do that, the foaming step is performed in a hot press. The methodology is optimized to produce flat samples with dimensions of 100 × 100 × 6 mm3, relative densities in the range 0.25–0.55 and cell sizes around 250 nm. Additionally, foaming parameters are modified to study their influence on the final cellular structure, and the materials produced in this paper are compared with samples produced by using a most conventional approach in which foaming step is conducted in a thermal bath. Results obtained show that an increment in the foaming temperature leads to a reduction in relative density and an increase of cell nucleation density. Moreover, differences in the final cellular structure for materials produced by both foaming routes are studied, proving that although there exist some differences, the mechanisms governing the nucleation and growing are the same in both processes, leading to the production of homogeneous materials with very similar cellular structures

Saccharification of microalgae biomass obtained from wastewater treatment by enzymatic hydrolysis. Effect of alkaline-peroxide pretreatment

An enzymatic method for the carbohydrate hydrolysis of different microalgae biomass cultivated in domestic (DWB) and pig manure (PMWB) wastewaters, at different storage conditions (fresh, freeze-dried and reconstituted), was evaluated. The DWB provided sugars yields between 40 and 63%, although low xylose yields (< 23.5%). Approximately 2% of this biomass was converted to byproducts as succinic, acetic and formic acids. For PMWB, a high fraction of the sugars (up to 87%) was extracted, but mainly converted into acetic, butyric and formic acids, which was attributed to the bacterial action. In addition, the performance of an alkaline-peroxide pretreatment, conducted for 1 hour, 50ºC and H2O2 concentrations from 1 to 7.5% (w/w), was essayed. The hydrolysis of pretreated microalgae supported a wide range of sugars extraction for DWB (55-90%), and 100% for PMWB. Nevertheless, a large fraction of these sugars (~30% for DWB and 100% for PMWB) was transformed to byproducts.INIA MICINN Junta de Castilla y Leó

Electromyographic Activity Evolution of Local Twitch Responses During Dry Needling of Latent Trigger Points in the Gastrocnemius Muscle: A Cross-Sectional Study

Trigger points (TrPs) are hypersensitive spots within taut bands of skeletal muscles that elicit referred pain and motor changes. Among the variety of techniques used for treating TrPs, dry needling is one of the most commonly applied interventions. The question of eliciting local twitch responses (LTRs) during TrP dry needling is unclear. Our main aim was to investigate the evolution of the electromyographic (EMG) peak activity of each LTR elicited during dry needling into latent TrPs of the gastrocnemius medialis muscle. Methods. Twenty asymptomatic subjects with latent TrPs in the gastrocnemius medialis muscle participated in this cross-sectional study. Changes in EMG signal amplitude (root mean square [RMS]) with superficial EMG were assessed five minutes before, during, and five minutes after dry needling. The peak RMS score of each LTR was calculated (every 0.5 sec). Results. Analysis of variance revealed a significant effect (F ¼ 29.069, P <0.001) showing a significant decrease of RMS peak amplitude after each subsequent LTR. Differences were significant (P <0.001) during the first three LTRs, and stable until the end of the procedure. No changes (P ¼0.958) were found for mean RMS data at rest before (mean ¼ 65.2 mv, 95% confidence interval [CI] ¼ 47.3–83.1) and after (61.0 mv, 95% CI ¼ 42.3–79.7) dry needling. Conclusions. We found that, in a series of LTRs elicited during the application of dry needling over latent TrPs in the medial gastrocnemius muscle, the RMS peak amplitude of each subsequent LTR decreased as compared with the initial RMS peak amplitude of previous LTRs. No changes in superficial EMG activity at rest were observed after dry needling of latent TrPs of the gastrocnemius medialis muscle.Ciencias de la Actividad Física y del Deport

Mechanomyographic measures of muscle contractile properties are influenced by electrode size and stimulation pulse duration

The aim was to determine the effects of changing pulse duration and electrode size on muscle contractile properties. Thirty-six healthy young male participated in the study (age 24.8 ± 5.8 years; height 178.2 ± 0.6 cm; body mass 71.8 ± 7.3 kg; self-reported weekly moderate intensity activity 3.5 ± 1.2 h·week−1). Tensiomyography was used to assess rectus femoris (RF) and vastus medialis (VM) muscles neuromuscular properties of the dominant leg according to the electrode size (3.2–5 cm) and the stimulus length (0.2, 0.5, and 1 ms). Maximal radial displacement (Dm); Contraction time (Tc); Delay time (Td); Sustained time (Ts) and Half relaxation time (Tr) were measured. Relative and absolute reliability was quantified. To analyze the effects of the electrode and the stimulus length, a repeated-measures analysis of variance was used. Dm and Tc parameters showed for both muscles an excellent relative (0.95–0.99) and absolute reliability (1.6–4.2%). However, Ts and Tr showed low values of absolute reliability (4.4–40.9%). The duration of the stimulus length applied to the RF and VM and electrode size significantly influences muscle’s contractile properties (p < 0.05; η2p = 0.09–0.60). The Dm increases substantially as the duration of the stimulus increases and with the use of the larger electrode in both muscles. However, Tc and Td are less affected by both conditions and not entirely clear. Practically, our study suggests that a stimulus pulse duration of 1 ms together with a 5 × 5 cm electrode is necessary to reach a reliable and reproducible assessment of both RF and VM muscles contractile properti

Mechanomyographic Measures of Muscle Contractile Properties are Infuenced by Electrode Size and Stimulation Pulse Duration

The aim was to determine the efects of changing pulse duration and electrode size on muscle contractile properties. Thirty-six healthy young male participated in the study (age 24.8±5.8 years; height 178.2±0.6cm; body mass 71.8±7.3kg; self-reported weekly moderate intensity activity 3.5±1.2h·week−1). Tensiomyography was used to assess rectus femoris (RF) and vastus medialis (VM) muscles neuromuscular properties of the dominant leg according to the electrode size (3.2–5cm) and the stimulus length (0.2, 0.5, and 1ms). Maximal radial displacement (Dm); Contraction time (Tc); Delay time (Td); Sustained time (Ts) and Half relaxation time (Tr) were measured. Relative and absolute reliability was quantifed. To analyze the efects of the electrode and the stimulus length, a repeated-measures analysis of variance was used. Dm and Tc parameters showed for both muscles an excellent relative (0.95–0.99) and absolute reliability (1.6–4.2%). However, Ts and Tr showed low values of absolute reliability (4.4–40.9%). The duration of the stimulus length applied to the RF and VM and electrode size signifcantly infuences muscle’s contractile properties (p<0.05; η2 p=0.09–0.60). The Dm increases substantially as the duration of the stimulus increases and with the use of the larger electrode in both muscles. However, Tc and Td are less afected by both conditions and not entirely clear. Practically, our study suggests that a stimulus pulse duration of 1ms together with a 5 × 5cm electrode is necessary to reach a reliable and reproducible assessment of both RF and VM muscles contractile properties.Ciencias de la Actividad Física y del Deport

Localization of Muscle Edema and Changes on Muscle Contractility After Dry Needling of Latent Trigger Points in the Gastrocnemius Muscle

Background. Myofascial trigger points (TrPs) are hyperirritable spots within taut bands of skeletal muscles that elicit local and referred pain when stimulated. Among the variety of techniques used for treating TrPs, dry needling (DN) is the most commonly applied intervention. The physiological mechanisms underlying the effects of DN remain to be elucidated. Objective. To examine changes in skeletal muscle after DN in the area where the TrP is located. Methods. We measured in vivo changes that occur in human skeletal muscle one hour after DN over a TrP with magnetic resonance imaging (MRI) and tensiomyography. The study included 18 asymptomatic subjects with a latent TrP in one medial gastrocnemius muscle, and the contralateral leg was used as control. Results. The results showed that MRI signal intensity significantly increased one hour after the DN intervention, suggesting the presence of intramuscular edema. Tensiomyographic parameters showed higher muscle stiffness with an improvement in contraction time after DN. Conclusions. This is the first study showing intramuscular edema after TrP DN in human skeletal muscle. Future research should focus on using DN therapy in patients with active TrPs and on monitoring changes occurring at longer follow-up with imaging techniques.Fisioterapi

Aula itinerante de Patrimonio Cultural II

Memoria final del PIMCD UCM 2020/2021 número 31