13 research outputs found

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

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    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

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    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

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    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

    A MECHATRONIC TOOL FOR REVEALING INVERSE RELATIONSHIPS AMONG HEART’S STROKE VOLUME AND HEAD’S LINEAR ACCELERATION INDUCED BY MOORED BOATS ROLLING IN ELDERLY SAILORS WITH UNCHANGED BODY SIZES: A NON-DRUG ANTI-HYPERTENSIVE ADVANTAGE?

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    Three aged and skilled sailors, being in a good condition of cardio metabolic compensation, took a seven days coastal sailing cruise. They daily underwent a cardiodynamic assessment by a impedance cardigraphy tool while staying seated on the moored boat. They showed a statistically significant inverse linear regression of beat-to-beat left ventricular stroke volume (LSV) versus the component of the head acceleration along the spatial X-axis, positioning the subject’s head so that the X-axis lay along the nose-ocipital direction. In fact, the temporally corresponding values of LSV inversely changed of about 11 ml on average, with an interindividual difference ranging from a minimum of about 6 ml to a maximum of about 14 ml, for each unitary head acceleration change. Since the reduction of left ventricular stroke volume may be due to the already observed vestibulo-sympathetic reflex from which limbs muscle vasodilation may occur, and considering that LSV falling induces a reduction in arterial blood pressure, it is hypothesized that the slow rolling of moored boat might also act as a non-invasive arterial blood pressure attenuator effect

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

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    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

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

    No full text
    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

    ELECTRICAL IMPEDANCE SPECTROSCOPY AS A FRIENDLY AND NON-INVASIVE METHOD TO REMOTELY CONTROL BODY MASS IN HOME CARE PATIENTS WITH OBESITY

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    According to the World Health Organization, obesity disease currently represents one of the main public health problems since it can influence the duration and quality of life with a high social cost, and the body mass index, as the ratio of body mass and the height squared, is considered as the measure to define obesity. However, in patients with severe obesity even moving from bed towards a weight scale could represent a very tiring and often risky action due to possible falls. Moving from previous evidences, in this study the electrical impedance spectroscopy method was applied to the dominant upper arm of 18 patients with obesity, with a a sweep of frequency configured from 10 to 300 kHz with a step of 1 kHz. The applied potential difference was 1 Vpp, with the current limited to 0.24 mA. Resulting values of the real part of the arms electrical impedance linearly and significantly correlates with patients’ body mass (P=0.0034) and body mass index (P=0.0427). These results consent of evaluate body mass changes in patients with severe obesity patients, from a simple application to an arm of an electrical current with very low intensity and relatively high frequency

    ELECTRICAL IMPEDANCE SPECTROSCOPY AS A FRIENDLY AND NON-INVASIVE METHOD TO REMOTELY CONTROL BODY MASS IN HOME CARE PATIENTS WITH OBESITY

    No full text
    According to the World Health Organization, obesity disease currently represents one of the main public health problems since it can influence the duration and quality of life with a high social cost, and the body mass index, as the ratio of body mass and the height squared, is considered as the measure to define obesity. However, in patients with severe obesity even moving from bed towards a weight scale could represent a very tiring and often risky action due to possible falls. Moving from previous evidences, in this study the electrical impedance spectroscopy method was applied to the dominant upper arm of 18 patients with obesity, with a a sweep of frequency configured from 10 to 300 kHz with a step of 1 kHz. The applied potential difference was 1 Vpp, with the current limited to 0.24 mA. Resulting values of the real part of the arms electrical impedance linearly and significantly correlates with patients’ body mass (P=0.0034) and body mass index (P=0.0427). These results consent of evaluate body mass changes in patients with severe obesity patients, from a simple application to an arm of an electrical current with very low intensity and relatively high frequency

    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

    Get PDF
    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

    A MECHATRONIC SIMULATOR OF AN AIRCRAFT COCKPIT TO STUDY, BY A VIRTUAL FLIGHT TEST, CARDIOVASCULAR FITNESS IN AIRLINE PILOTS BANNED TO FLY SINCE COVID-19 LOCKDOWN

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    During flying airline pilots cardio-vascular adaptations occur producing a steady condition of bradycardia and low values in arterial blood pressure. The ability to maintain this optimal level of cardiovascular fitness in aircraft pilots during a prolonged non-driving period is reduced proportionally to this interval. The COVID-19 pandemic has forced pilots to inactivity due to the interruption of many flights at the start of the pandemic. We tested the cardiovascular profile in seven skilled pilots, after 26 weeks of banned to flying for the pandemic lockdown, while they virtually drove an entirely self-built aircraft Airbus A320 simulator. The aim was to investigate on their possible circulatory impairments. Beat-to-beat cardiodynamic profile was non invasively and remotely assessed by a homemade impedance cardiography ICT platform, i.e. the e-Physio tool. Results showed an en route high mean arterial blood pressure (almost 104 Torr) mainly sustained by excessively high values of peripheral vascular resistance (more than 24 Torr per dm3 per minute). Properly central-cardiac hemodynamic and chronotropic modulators of the stroke volume (ventricle end diastolic volume and contractility, heart rate) did not change significantly. Since this hemodynamic picture resembles that of heart failure, it was concluded that (due to the covid-19 dependent long period of inactivity) pilots may go towards a condition of detraining that involved the loss of specific cardiovascular adaptations capable of buffering risks of arterial hypertension
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