Optimization of Dimensions of Cylindrical Piezoceramics as Radio-Clean Low Frequency Acoustic Sensors

[EN] Circular piezoelectric transducers with axial polarization are proposed as low frequency acoustic sensors for dark matter bubble chamber detectors. The axial vibration behaviour of the transducer is studied by three different methods: analytical models, FEM simulation, and experimental setup. To optimize disk geometry for this application, the dependence of the vibrational modes in function of the diameter-to-thickness ratio from 0.5 (a tall cylinder) to 20.0 (a thin disk) has been studied. Resonant and antiresonant frequencies for each of the lowest modes are determined and electromechanical coupling coefficients are calculated. From this analysis, due to the requirements of radiopurity and little volume, optimal diameter-to-thickness ratios for good transducer performance are discussed.The authors acknowledge the financial support of the Spanish Ministerio de Economia y Competitividad (MINECO), Grants FPA-2015-65150-C3-2P, and Consolider MultiDark CSD2009-00064. Thanks as well are due to the PICO Collaboration members for the fruitful discussions, suggestions, and comments.Ardid Ramírez, M.; Felis-Enguix, I.; Martínez Mora, JA.; Otero-Vega, JE. (2017). Optimization of Dimensions of Cylindrical Piezoceramics as Radio-Clean Low Frequency Acoustic Sensors. Journal of Sensors. 1-8. https://doi.org/10.1155/2017/81796721

Cost and energy efficient reconfigurable embedded platform using Spartan-6 FPGAs

Modern FPGAs with run-time reconfiguration allow the implementation of complex systems offering both the flexibility of software-based solutions combined with the performance of hardware. This combination of characteristics, together with the development of new specific methodologies, make feasible to reach new points of the system design space, and make embedded systems built on these platforms acquire more and more importance. However, the practical exploitation of this technique in fields that traditionally have relied on resource restricted embedded systems, is mainly limited by strict power consumption requirements, the cost and the high dependence of DPR techniques with the specific features of the device technology underneath. In this work, we tackle the previously reported problems, designing a reconfigurable platform based on the low-cost and low-power consuming Spartan-6 FPGA family. The full process to develop the platform will be detailed in the paper from scratch. In addition, the implementation of the reconfiguration mechanism, including two profiles, is reported. The first profile is a low-area and low-speed reconfiguration engine based mainly on software functions running on the embedded processor, while the other one is a hardware version of the same engine, implemented in the FPGA logic. This reconfiguration hardware block has been originally designed to the Virtex-5 family, and its porting process will be also described in this work, facing the interoperability problem among different families

Yeast and its derivatives as ingredients in the food industry

In the last 200 years, and still today, yeast is well known for its application in brewing, alcohol fermentation and wine and bread making. They are an endless source of new food ingredients and additives with excellent functional and nutritional properties, now through the use of innovative elaboration and fractionation techniques that come mainly from biotechnology. The book reviewed here contains fourteen chapters in 246 pages that deal with yeasts employed as food ingredients and their potential as Nutraceutics. It compiles the expertise of three Latin American institutionsthat have given priority to the generation of basic knowledge on yeast and set the grounds for the development of new technologies based on these microorganisms. This is a sample of the alternatives offered by yeast in the fields of food science and technology.Fil: Otero, Miguel A.. Instituto Cubano de Investigaciones de los Derivados de la Caña de Azúcar; CubaFil: Guerrero, Isabel. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Investigación en Funcionalidad y Tecnología de Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Wagner, Jorge Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cabello, Agustín J.. Instituto Cubano de Investigaciones de los Derivados de la Caña de Azúcar; CubaFil: Sceni, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: García, Roxana. Instituto Cubano de Investigaciones de los Derivados de la Caña de Azúcar; CubaFil: Soriano, Jorge. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Investigación en Funcionalidad y Tecnología de Alimentos; ArgentinaFil: Tomasini, Araceli. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Investigación en Funcionalidad y Tecnología de Alimentos; ArgentinaFil: Saura, Gustavo. Instituto Cubano de Investigaciones de los Derivados de la Caña de Azúcar; CubaFil: Almazán, Oscar. Instituto Cubano de Investigaciones de los Derivados de la Caña de Azúcar; Cub

Assessment of over-the-head resuscitation method in an inflatable rescue boat sailing at full speed. A non-inferiority pilot study

Introduction: Drowning is a public health problem. Interrupting the drowning process as soon as possible and starting cardiopulmonary resuscitation (CPR) can improve survival rates. Inflatable rescue boats (IRBs) are widely used worldwide to rescue drowning victims. Performing CPR in special circumstances requires adjusting the position based on the environment and space available. The aim of this study was to assess the quality of over-the-head resuscitation performed by rescuers aboard an IRB in comparison to standard CPR.Methods: A quasi-experimental, quantitative, cross-sectional pilot study was conducted. Ten professional rescuers performed 1 min of simulated CPR on a QCPR Resuscy Anne manikin (Laerdal, Norway) sailing at 20 knots using two different techniques: 1) standard CPR (S-CPR) and 2) over-the-head CPR (OTH-CPR). Data were recorded through the APP QCPR Training (Laerdal, Norway).Results: The quality of CPR was similar between S-CPR (61%) and OTH-CPR (66%), with no statistically significant differences (p = 0.585). Both the percentage of compressions and the percentage of correct ventilations did not show significant differences (p > 0.05) between the techniques.Conclusion: The rescuers can perform CPR maneuvers with acceptable quality in the IRB. The OTH-CPR technique did not show inferiority compared to S-CPR, making it a viable alternative when boat space or rescue conditions do not allow the conventional technique to be performed.Universidade de Vigo/CISU

Simple low-cost construction and calibration of accurate pneumotachographs for monitoring mechanical ventilation in low-resource settings

Assessing tidal volume during mechanical ventilation is critical to improving gas exchange while avoiding ventilator-induced lung injury. Conventional flow and volume measurements are usually carried out by built-in pneumotachographs in the ventilator or by stand-alone flowmeters. Such flow/volume measurement devices are expensive and thus usually unaffordable in low-resource settings. Here, we aimed to design and test low-cost and technically-simple calibration and assembly pneumotachographs. The proposed pneumotachographs are made by manual perforation of a plate with a domestic drill. Their pressure-volume relationship is characterized by a quadratic equation with parameters that can be tailored by the number and diameter of the perforations. We show that the calibration parameters of the pneumotachographs can be measured through two maneuvers with a conventional resuscitation bag and by assessing the maneuver volumes with a cheap and straightforward water displacement setting. We assessed the performance of the simplified low-cost pneumotachographs to measure flow/volume during mechanical ventilation as carried out under typical conditions in low-resource settings, i.e., lacking gold standard expensive devices. Under realistic mechanical ventilation settings (pressure- and volume-control; 200-600 mL), inspiratory tidal volume was accurately measured (errors of 2.1% on average and <4% in the worst case). In conclusion, a simple, low-cost procedure facilitates the construction of affordable and accurate pneumotachographs for monitoring mechanical ventilation in low- and middle-income countries

Profile of antiretroviral agents use in Colombia

Introduction: Since the beginning of the epidemic, human immunodeficiency virus (HIV) has taken more than 36 million lives. Objective: To determine the antiretroviral drug prescription patterns in a population of individuals with HIV infection in Colombia. Materials and methods: Cross-sectional study analyzing the profiles of patients treated with antiretroviral drugs between April 1st and September 30th, 2015. The sociodemographic, pharmacological, and comorbidity variables were identified. Individuals with a positive diagnosis of HIV of all ages and both genders were included. Results: We found 641 patients with a mean age of 39.0±17 years who were predominantly male (60.2%). The most used medications were lamivudine-zidovudine (51.6%), lopinavir-ritonavir (36%) and efavirenz (24.5%). The combination of lamivudine-zidovudine plus lopinavir-ritonavir was the most prescribed regimen (29.5%), but a total of 80 different regimens was identified. Being an adult between the ages of 45-64 years (OR=2.25; 95%CI 1.367-3.713) was associated with a greater probability of receiving 4 or more antiretrovirals. A total of 267 (41.6%) patients used at least one comedication (range: 1-18 drugs), especially anti-ulcer (57.3%), lipid-lowering (28.8%) and anti-hypertensive (28.5%) drugs. Conclusions: Patients undergoing antiretroviral treatment are receiving medications with elevated intrinsic values at the recommended doses and present comorbidities associated with chronic agerelated conditions. However, these patients receive a great variety of regimens that are not included in the clinical practice guidelines

Monitorización acústica con cerámicas piezoeléctricas en aplicaciones médicas con haces de protones

[ES] En este artículo se presenta la monitorización acústica del uso de partículas pesadas en tratamientos oncológicos con haces de protones a partir del estudio de la señal de presión generada por el efecto termoacústico debido a la incidencia de un haz de protones con una energía de 100 MeV para un caso específico de ependioma. El perfil espacial de la deposición de energía ha sido simulado empleando el método Monte Carlo en la herramienta de cálculo Geant4 junto con las librerías disponibles para incluir la interacción de las partículas con el tejido cerebral y la estructura ósea del cráneo. La señal termoacústica resultante es obtenida discretizando una solución particular de la ecuación de ondas termoacústica. Con esto, la fase de propagación y transmisión se ha simulado empleando el método de elementos finitos (FEM). Finalmente, se ha reconstruido la posición de la fuente de energía depositada evaluando el tiempo de llegada (TOA) a un conjunto de puntos sobre la superficie del cráneo.[EN] This article presents the acoustic monitoring of the use of heavy particles in oncological treatments with proton beams from the study of the pressure signal generated by the thermoacoustic effect due to the incidence of a proton beam with an energy of 100 MeV for a specific case of ependyoma. The spatial profile of the energy deposition has been simulated using the Monte Carlo method in the Geant4 calculation tool together with the available libraries to include the interaction of the particles with the brain tissue and the bone structure of the skull. The resulting thermoacoustic signal is obtained by discretizing a particular solution of the thermoacoustic wave equation. With this, the propagation and transmission phase has been simulated using the finite element method (FEM). Finally, the position of the deposited energy source has been reconstructed by evaluating the time of arrival (TOA) at a set of points on the surface of the skull.Otero-Vega, JE.; Felis-Enguix, I.; Ardid Ramírez, M.; Herrero Debón, A. (2020). Monitorización acústica con cerámicas piezoeléctricas en aplicaciones médicas con haces de protones. Revista de Acústica. 51(3-4):3-9. http://hdl.handle.net/10251/176278S39513-

Low-cost, open-source device for simultaneously subjecting rodents to different circadian cycles of light, food, and temperature

Exposure of experimental rodents to controlled cycles of light, food, and temperature is important when investigating alterations in circadian cycles that profoundly influence health and disease. However, applying such stimuli simultaneously is difficult in practice. We aimed to design, build, test, and open-source describe a simple device that subjects a conventional mouse cage to independent cycles of physiologically relevant environmental variables. The device is based on a box enclosing the rodent cage to modify the light, feeding, and temperature environments. The device provides temperature-controlled air conditioning (heating or cooling) by a Peltier module and includes programmable feeding and illumination. All functions are set by a user-friendly front panel for independent cycle programming. Bench testing with a model simulating the CO2 production of mice in the cage showed: a) suitable air renewal (by measuring actual ambient CO2), b) controlled realistic illumination at the mouse enclosure (measured by a photometer), c) stable temperature control, and d) correct cycling of light, feeding, and temperature. The cost of all the supplies (retail purchased by e-commerce) was &lt;300 US$. Detailed technical information is open-source provided, allowing for any user to reliably reproduce or modify the device. This approach can considerably facilitate circadian research since using one of the described low-cost devices for any mouse group with a given light-food-temperature paradigm allows for all the experiments to be performed simultaneously, thereby requiring no changes in the light/temperature of a general-use laboratory