Possible Assessment of Calf Venous Pump Efficiency by Computational Fluid Dynamics Approach

Three-dimensional simulations of peripheral, deep venous flow during muscular exercise in limbs of healthy subjects and in those with venous dysfunction were carried out by a computational fluid-dynamics (CFD) approach using the STAR CCM + platform. The aim was to assess the effects of valvular incompetence on the venous calf pump efficiency. The model idealizes the lower limb circulation by a single artery, a capillary bed represented by a porous region and a single vein. The focus is on a segment of the circuit which mimics a typical deep vein at the level of the calf muscle, such as the right posterior tibial vein. Valves are idealized as ball valves, and periodic muscle contractions are given by imposing time-dependent boundary conditions to the calf segment wall. Flow measurements were performed in two cross-sections downstream and upstream of the calf pump. Model results demonstrate a reduced venous return for incompetent valves during calf exercise. Two different degrees of valvular incompetence are considered, by restricting the motion of one or both valves. Model results showed that only the proximal valve is critical, with a 30% reduction of venous return during calf exercise in case of valvular incompetence: the net flow volume ejected by the calf in central direction was 0.14 mL per working cycle, against 0.2 mL for simulated healthy limbs. This finding appeared to be consistent with a 25% reduction of the calf ejection fraction, experimentally observed in chronic venous disease limbs compared with healthy limbs

Mechatronic face mask anti covid-19 to remotely record cardiorespiratory variables in farm’s workers engaged in jobs at high risk of infection

The most frequent prodromes of COVID-19 infection are fever, signs of respiratory diseases, cough and shortness of breath. Nevertheless, it is not infrequent that patients with COVID-19 also show cardiac symptoms. So, it is of importance to detect the prodromal symptoms of the COVID-19 infection in order to be able to make a diagnosis as quickly as possible to provide the immediate insertion of the infected people in isolation/therapy protocols. Here is presented a prototype of a smart face mask, named AG47-SmartMask that, in addition to the function of both an active and passive anti COVID-19 filter by an electro-heated filter brought to a minimum temperature of 38°C, it also allows the continuous monitoring of numerous cardio-pulmonary variables. Several specific sensors are incorporated into the mask to assess the inside mask temperature from which synchronous waving with the breathing was acquired the breath frequency, relative humidity, air pressure together and end tidal carbon dioxide percentage, and an auricular assessment of the body temperature, the heart rate and the percentage of oxygen saturation of haemoglobin. Sensors are embedded within an advanced ICT platform. To validate the AG47-SmartMask tool, were engaged twenty seven Farm’s workers of a vegetable packaging chain and they dressed the face mask device to simulate, while working, both tachypnea and cough, and the AG47-SmartMask faithfully quantified the simulated dyspnoic events

Assessing simulated arm lymphoedema by a prototype of bioimpedance spectroscopy device. Possible implication of its use in the follow up of patients who underwent extensive breast cancer surgery

The aim of this research was to enable women after breast cancer surgery, in which arms lymphoedema often occurs, to self-monitor this disease using in-home an easy-to-use-device which assesses the arm’s resistance ratio, considered an indirect, non-invasive index of increased extracellular water volume in those limbs. An homemade equipment based on the bioimpedance spectroscopy technique, was tested on 20 healthy volunteers which, by means of two ECG disposable electrodes, connected to the device both their dominant and auxiliary upper arms and changes in electrical resistance were assessed while an alternate current of low intensity and sweeping frequency from 15 to 75 kHz had be injected. In the same volunteers, an arm lymphoedema with about 100 ml excess of extracellular water was simulated by subtracting 0.8% from measured resistance values in each arm. The arms’ resistance ratio against the increasing frequency gave rise to a parabolic branch visible on a mobile phone screen and, when the arm lymphoedema was simulated, the corresponding curve appeared positioned below that of the one without oedema. The patient’s self-awareness, due to the device’s self-management, could allow these subjects to actively approach the disease while sharing their results remotely with clinical specialists by an internet connection

Wireless connection of bioimpedance measurement circuits based-on AD5933: a state of the art

Bioimpedance Spectroscopy measurements and Cole-Cole models are commonly used to characterize biological systems. Cole-Cole model parameters may be obtained by fittingthe measured bioimpedance data into a semicircle. This work proposes an iterative method to approximate a bioimpedance dataset to a Cole-Cole model analysis using only three points.The performance of the proposed method was compared against similar methods reported in a recent publication; our proposal presents greater efficiency (87.5%) and lower mean error (0.022)than the compared methods. The main contribution of the proposed method is that its performance does not rely on the user?s technical knowledge, neither does it on the instrument used to perform the measurements, while the compared methods do.Fil: Dell'osa, Antonio Héctor. Universidad Nacional de Tierra del Fuego. Instituto de Desarrollo Economico E Innovacion; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Villanueva Jousset, T.. Universidad Nacional de Tierra del Fuego. Instituto de Desarrollo Economico E Innovacion; ArgentinaFil: Ames Lastra, G.. Universidad Autónoma Metropolitana; MéxicoFil: Concu, A.. Università Degli Studi Di Cagliari.; Italia43rd Annual International Conference of the IEEE Engineering in Medicine & Biology SocietyGuadalajaraMéxicoInstitute of Electrical and Electronics Engineer

Low cost Bioimpedance Applications: a solution to the csv files problem for the AD5933EB

Las mediciones de bioimpedancia brindan información sobre las propiedades eléctricas de diferentes sistemas biológicos. Los equipos comerciales para tomar este tipo de mediciones, bioimpedanciómetros, poseen un valor alto. Sumado a su costo en países como Argentina la importación de los mismos suele ser otro inconveniente. Es por esto que son de amplia utilización placas de evaluación como la AD5933EB (Analog Devices, USA) y la AFE4300 (Texas Instruments, USA) para tomar mediciones experimentales. La placa AD5933EB, mediante su software, entrega un archivo extensión .csv con los datos medidos, pero este archivo posee un patrón de edición que constituye una falla para los sistemas operativos en lenguas de origen latino: la separación de los valores y la separación de la parte entera y la parte decimal de un número real se realiza con caracteres coma (?,?), lo que produce un error al separar los datos de cada variable con herramientas de análisis de datos convencionales. Nuestro grupo genero el planteo de tres posibles soluciones alcanzando la mejor implementación con el uso de una expresión regular. Finalmente se generó una aplicación para reparar los archivos entregados por la placa AD5933EB disponible en http://bioimpedancia.untdf.edu.ar.Fil: Alvarez, Alejandro A.. Universidad Nacional de Tierra del Fuego. Instituto de Desarrollo Economico E Innovacion; ArgentinaFil: Maciel, Sergio D.. Universidad Nacional de Tierra del Fuego. Instituto de Desarrollo Economico E Innovacion; ArgentinaFil: Pérez, Ignacio Augusto. Universidad Nacional de Tierra del Fuego. Instituto de Desarrollo Economico E Innovacion; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rigoni, Brian A.. Universidad Nacional de Tierra del Fuego. Instituto de Desarrollo Economico E Innovacion; ArgentinaFil: Dell'osa, Antonio Héctor. Universidad Nacional de Tierra del Fuego. Instituto de Desarrollo Economico E Innovacion; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaXX Congreso Argentino de BioingenieríaPiriapolisUruguaySociedad Argentina de Bioingenierí

Innovative smart face mask to protect workers from COVID-19 infection

The most frequent prodromes of COVID-19 infection are fever and signs/symptoms of incipient respiratory diseases such as cough and shortness of breath or tachypnea. However, it is not infrequent that in patients infected with COVID-19, in addition to respiratory manifestations, cardiac rhythm alterations are also present which can be an early sign of an acute cardiovascular syndrome. It is therefore of utmost importance, especially for health care and civil protection workers who are most exposed to the infection, to detect the prodromal symptoms of this infection in order to be able to make a diagnosis of possible positivity to COVID-19 infection as quickly as possible and therefore to provide their immediate insertion in the isolation/therapy protocols. Here a prototype of a smart face mask is presented: the AG47-SmartMask. In addition to having the function of both an active and passive anti COVID-19 filter, the latter by an electro-heated filter brought to a minimum temperature of 38°C, the AG47-SmartMask also allows the continuous monitoring of numerous cardio-pulmonary variables. Several specific sensors are incorporated into the mask in an original way that assess the inside mask temperature, relative humidity and air pressure together with the auricular assessment of body temperature, heart rate and percentage of oxygen saturation of haemoglobin. Sensors work in synergy with an advanced telemedicine platform. To validate the device, twenty workers engaged in a vegetable packaging chain tested the tool simulating, while working, both tachypnea and cough, and the AG47-SmartMask faithfully quantified the simulated dyspnoic events

Bio-electrical impedance device for remote control of an indirect index of mechanical tenderness in ripening beef meat

With the aim to contribute in increasing the meat beef preference from consumers on the basis of their unbiased knowledge of meat tenderness, we have built an information and communication technology platform: the ICTZm, based on the measure of the ratio between the transversal resistivity and the longitudinal one of the muscle fibres, i.e. the electrical anisotropy ratio (RT/RL), which decreases during the ripening period of the meat while increasing mechanical tenderness since its mechanical resistance to compression stress decreases. For this we integrated a commercial electronic board generating a constant current (1 mA at 65 KHz) together with a command and control system and a remote data acquisition system by which RT/RL values of 6 beef longissimus dorsi muscle portion from 3 young cattle where remotely assessed, along the processing line, within 14 days from slaughter at 5°C. From assessed data we obtained a nonlinear equation, of the symmetrical sigmoidal type, which fitted curve consents to obtain the RT/RL value at a given day from slaughter (R2 = 0.96). So our ICTZm allowed us to acquire numerical values from which an indirect but objective index of meat mechanical resistance/tenderness could be furnished to the consumer

Differences in the Electrical Impedance Spectroscopy variables between right and left forearms in healthy people: a non invasive method to easy monitoring structural changes in human limbs?

The resistive component of bioimpedance was non invasively assessed in both right and left upper arms of 11 healthy female and 9 male subjects (28.4 ± 1.4 years; 63.8 ± 11.8 kg; 167.4 ± 7.5 cm) all of whom were right-handed. A home-made electrical impedance spectroscopy device which implemented the AD 5933 electronic board was utilized, and the bipolar modality of bioimpedance assess-ment was chosen using two disposable ECG surface electrodes placed at each end of the biceps brachial muscles while subjects were sitting comfortably. Upper arm resistance was acquired at sweeping frequency steps of 15, 30, 45, 60 and 75 KHz. Results showed a significantly lower mean value of resistance in right ver-sus left upper arms: - 27.4 Ω, P<0.05 or about -4%, at the frequency of 15 KHz. It was concluded that some errors of data interpretation may occur in the case of lymphedema in one arm and thus, electrical impedance spectroscopy was utilized to monitor the water volume trend in that arm in comparison with the other arm. These results underline a predominantly low value of the resistance in the main upper arm compared to that in the auxiliary one, even in healthy subjects. There-fore, care must be taken when the electrical impedance spectroscopy is adopted in these clinical assessments.Fil: Dell'osa, Antonio Héctor. Universidad Nacional de Tierra del Fuego. Instituto de Desarrollo Economico E Innovacion; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Concu, Alberto. Università Degli Studi Di Cagliari.; ItaliaFil: Fois, A.. No especifíca;Fil: Mela, Q.. No especifíca;Fil: Capone, A.. Università Degli Studi Di Cagliari.; ItaliaFil: Marongiu, G.. Università Degli Studi Di Cagliari.; ItaliaFil: Loviselli, Andrea. Università Degli Studi Di Cagliari.; ItaliaFil: Velluzzi, Fernanda. Università Degli Studi Di Cagliari.; Italia17th International Conference on Electrical BioimpedanceJoinvilleBrasilInternational Society on Electrical Bio Impedanc

Electrical impedance to easily discover undeclared freeze-thaw cycles in slaughtered bovine meat

A portable electrical impedance spectroscopy device was developed to monitor the bioimpedance resistive component of bovine meat by injecting a sinusoidal current of 1 mA at 65 kHz. Both right and left longissimus dorsi muscles were trimmed from 4 slaughtered cows. The left muscle portions were frozen to -18 °C for 7 days while the right ones were meantime maintained at 5 °C. Mean value of impedance per length (Ω/cm) of frozen and thawed left samples was 31% lower than that of right non-frozen one (P = 0.0001). It was concluded that the device is reliable for monitoring the maturation of beef meat in situ with the possibility of revealing undeclared freeze-thaw cycles.Fil: Dell'osa, Antonio Héctor. Universidad Nacional de Tierra del Fuego. Instituto de Desarrollo Economico E Innovacion; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Battacone, G.. Università Degli Studi Di Sassari; ItaliaFil: Pulina, G.. Università Degli Studi Di Sassari; ItaliaFil: Fois, A.. No especifíca;Fil: Tocco, Fabricio. Università Degli Studi Di Cagliari.; ItaliaFil: Loviselli, A.. Università Degli Studi Di Cagliari.; ItaliaFil: Concu, A.. Università Degli Studi Di Cagliari.; ItaliaFil: Velluzzi, F.. Università Degli Studi Di Cagliari.; Itali

Mechatronic face mask anti covid-19 to remotely record cardiorespiratory variables in farm’s workers engaged in jobs at high risk of infection

The most frequent prodromes of COVID-19 infection are fever, signs of respiratory diseases, cough and shortness of breath. Nevertheless, it is not infrequent that patients with COVID-19 also show cardiac symptoms. So, it is of importance to detect the prodromal symptoms of the COVID-19 infection in order to be able to make a diagnosis as quickly as possible to provide the immediate insertion of the infected people in isolation/therapy protocols. Here is presented a prototype of a smart face mask, named AG47-SmartMask that, in addition to the function of both an active and passive anti COVID-19 filter by an electro-heated filter brought to a minimum temperature of 38°C, it also allows the continuous monitoring of numerous cardio-pulmonary variables. Several specific sensors are incorporated into the mask to assess the inside mask temperature from which synchronous waving with the breathing was acquired the breath frequency, relative humidity, air pressure together and end tidal carbon dioxide percentage, and an auricular assessment of the body temperature, the heart rate and the percentage of oxygen saturation of haemoglobin. Sensors are embedded within an advanced ICT platform. To validate the AG47-SmartMask tool, were engaged twenty seven Farm’s workers of a vegetable packaging chain and they dressed the face mask device to simulate, while working, both tachypnea and cough, and the AG47-SmartMask faithfully quantified the simulated dyspnoic events