Search results for "beat"
showing 10 items of 229 documents
Quantification of Different Regulatory Pathways Contributing to Heartbeat Dynamics during Multiple Stimuli: a Proof of the Concept.
2019
The dynamical interplay between brain and heart is mediated by several feedback mechanisms including the central autonomic network and baroreflex loop at a peripheral level, also for a short-term regulation. State of the art focused on the characterization of each regulatory pathway through a single stressor elicitation. However, no studies targeted the actual quantification of different mediating routes leading to the generation of heartbeat dynamics, particularly in case of combined exogenous stimuli. In this study, we propose a new approach based on computational modeling to quantify the contribution of multiple concurrent stimuli in modulating cardiovascular dynamics. In this prelimina…
High Degree of Realism in Teaching Percutaneous Coronary Interventions by Combining a Virtual Reality Trainer With a Full Scale Patient Simulator
2008
The virtual reality coronary angiography simulator "CATHI" (Catheter Instruction System, Mannheim, Germany) simulates coronary arteries with implemented vessel lesions in virtual patients. Like similar systems the software model runs on common PC systems, which are linked to the mechanical device for manual training. We combined the advantages of this skill trainer with the near to reality assembly of a cardiac catheterization laboratory (Cath-lab) by connecting it to a full scale simulator (HPS, METI, Sarasota, FL). We present two methods of synchronizing the heartbeat between both simulation devices. Method A-the hardware solution-uses the electrocardiogram-synchronization signal of the H…
Towards Disentangling the Contribution of Different Pathways for the Regulation of Cardiac Activity: A Pilot Study
2020
Heartbeat is dynamically regulated through mediating routes associated with central and peripheral feedback mechanisms. Previous studies focused on the quantification of these mechanisms in the presence of a single stressor. In this pilot study we propose a model aimed to quantify the contribution of different heartbeat regulatory routes while multiple stressors are administrated to the subject. The model is tested with Heart rate Variability (HRV) series from 26 subjects undergoing physical and affective stressors. Results show that the physical stressor prevalently (74%) contributes in mediating cardiac vagal control dynamics in case of concurrent affective elicitation. These results may …
An improved noninvasive method for measuring heartbeat of intertidal animals
2013
Since its emergence two decades ago, the use of infrared technology for noninvasively measuring the heartbeat rates of invertebrates has provided valuable insight into the physiology and ecology of intertidal organisms. During that time period, the hardware needed for this method has been adapted to currently available electronic components, making the original published description obsolete. This article reviews the history of heartbeat sensing technology, and describes the design and function of a modern and simplified infrared heartbeat rate sensing system compatible with many intertidal and marine invertebrates. This technique overcomes drawbacks and obstacles encountered with previous …
Quantifying multidimensional control mechanisms of cardiovascular dynamics during multiple concurrent stressors
2021
Heartbeat regulation is achieved through different routes originating from central autonomic network sources, as well as peripheral control mechanisms. While previous studies successfully characterized cardiovascular regulatory mechanisms during a single stressor, to the best of our knowledge, a combination of multiple concurrent elicitations leading to the activation of different autonomic regulatory routes has not been investigated yet. Therefore, in this study, we propose a novel modeling framework for the quantification of heartbeat regulatory mechanisms driven by different neural routes. The framework is evaluated using two heartbeat datasets gathered from healthy subjects undergoing p…
Remote Photoplethysmography measurement using constrained ICA
2017
Remote Photoplethysmography (rPPG) is a technique that consists in estimating physiological parameters such as heart rate from live or recorded video sequences taken by conventional camera or even webcams. This technique is increasingly used in many application fields thanks to its simplicity and affordability. The basic idea is that the arterial blood flow shows regularity due to the heartbeat. This regularity is manifested by very small periodic variations in the color of the skin, which can be isolated and quantified by signal and image processing methods. In this context, Independent Component Analysis (ICA) is largely used to separate the signal due to arterial flow from signals from o…
<title>Optical non-invasive monitoring of skin blood pulsations</title>
2005
Time resolved detection and analysis of the skin backscattered optical signals (remission photoplethysmography or PPG) provide rich information on skin blood volume pulsations and can serve for reliable cardiovascular assessment. The single- and multi-channel PPG concepts are discussed in this work. Simultaneous data flow from several body locations allows one to study the heartbeat pulse wave propagation in real time and evaluate the vascular resistance. Portable single-, dual- and four-channel PPG monitoring devices with special software have been designed for real-time data acquisition and processing. The clinical studies confirmed their potential in the monitoring of heart arrhythmias, …
Controvèrsia inquisitorial al segle XVIII entorn de la pintura d’una beata estigmatitzada
2016
Resum: L’any 1738, un frare del convent de Sant Domingo de Palma havia de defensar unes «Conclusions literaries» teologiques, dedicades a la beata dominica Llucia de Narni. El full de propaganda de l’acte que s’havia repartit duia impresa una lamina de la beata, amb les llagues dels estigmes a les mans i al costat. El tribunal de la inquisicio, arran d’una denuncia dels franciscans observants, va manar que se suspengues aquest acte academic. Els dominics apel·laren a Madrid i a Roma. Aquest es un exemple mes de com les dones -a mes d’altres estigmatitzats- foren victimes de l’actitud monopolista dels franciscans, aixi com una expressio dels enfrontaments cronics entre els ordes mendicants m…
Aproximación al estudio sobre el Modelo de mujer espiritual de los eclesiásticos en la Edad Moderna
2016
Resumen: El modelo de mujer espiritual, de beata, fue siempre el mismo a lo largo de la Edad Moderna. En todas las vidas de mujeres, los biógrafos siguieron un patrón o arquetipo y éste se reprodujo hasta bien entrado el siglo XVIII, y perduró hasta el siglo XIX. No obstante, es necesario profundizar en cada una de las biografías para comprender que cada vida de mujer fue también única y singular. Solamente de este modo cada una de estas mujeres podrá recobrar el protagonismo que tuvo. Palabras clave: Beata, Edad Moderna, biografía, confesores, espiritualidad. Abstract: The model of a spiritual woman, a laywoman (beata), was always the same all throughout Modern Age. In all women’s live…
In Nomine sanctissimae, & indiuiduae Trinitatis ... Nouerint vniuersi, & singuli hoc praesens publicum trāsumpti instrumentum visuri, lecturi parite…
1609
El Notario Apostólico Blas Godouer, con fecha de Madrid, 7 de Noviembre de 1609, da fe de que concuerdan con los documentos originales las letras testimoniales y el decreto impresos Esc. de la Companyia de Jesús al començament del text Sign.: [ ]2