Comparison of two cardiac output monitors, qCO and LiDCO, during general anesthesia

Background: Optimization of cardiac output (CO) has been evidenced to reduce postoperative complications and to expedite the recovery. Likewise, CO and other dynamic cardiac parameters can describe the systemic blood flow and tissue oxygenation state and can be useful in different clinical fields. This study aimed to validate the qCO monitor (Quantium Medical, Barcelona, Spain), a new device to estimate CO and other related parameters in a continuous, fully non-invasive way using advanced digital signal processing of impedance cardiography. Methods: The LiDCOrapidv2 (LiDCO Ltd, London, UK) was used to compare the performance of the qCO in 15 patients during major surgery under general anesthesia. Full surgeries were recorded and cardiac output obtained by both devices was compared by using correlation and Bland-Altman analysis. Results: The Bland-Altman analysis showed sufficient agreement with a mean bias of -0.03 ± 0.71 L/min. Conclusions: The findings showed that both systems offered comparable values and thus the non-invasive measurement of CO with qCO is a promising, feasible method. Further investigation will be required to validate this new device against calibrated devices and outcome studies would also be highly recommended.Postprint (author's final draft

Symbolic Dynamics applied to Electroencephalographic signals to Predict Response to Noxious Stimulation during Sedation-Analgesia

The level of sedation in patients undergoing medical procedures evolves continuously since the effect of the anesthetic and analgesic agents is counteracted by noxious stimuli. The monitors of depth of anesthesia, based on the analysis of the electroencephalogram (EEG), have been progressively introduced into the daily practice to provide additional information about the state of the patient. However, the quantification of analgesia still remains an open problem. In this project, a methodology based on non-linear techniques signal processing algorithms was developed and applied to the electroencephalogram (EEG) for predicting responses to noxious stimulation during Sedation-Analgesia. Two types of stimuli were performed by the anesthesiologist during the surgery sessions, RSS (Ramsay Sedation Scale) and GAG (gag reflex). These sedation scales are considered gold standard. In this work, the scope of the project includes: EEG preprocessing, processing and analysis of the mentioned signals. The methodology included an EEG signal preprocessing, a time-domain and frequency-domain analysis, the development and application of non-linear techniques, a statistical analysis and finally the validation of the results. Symbolic dynamics methodology, already applied to other kind of signals, was used as a non-linear technique. The aim was to extract a set of patterns from the EEG obtained through two proposed non-linear algorithms. The symbolic dynamics consists of the transformation of the time signal in a series of symbols by an algorithm. From these new series, words of three symbols were constructed with one symbol delay and their occurrence probability was evaluated in the signals variables. Base on this, the Shannon and Rényi entropies were applied to estimate the complexity of the distribution of the variables. Moreover, thresholds on probabilities were used to construct new variables. The analysis was applied to the EEG filtered according to the characteristic frequency bands (EEG rhythms). The parameters involved in the algorithms were statistically adjusted in order to better characterize the nociceptive response. Variables obtained from linear and non-linear methodologies were submitted to a statistical analysis using a nonparametric test and a linear discriminant analyses to assess the quality of the classification. The leaving-one-out method was used as validation criteria. New defined variables were able to describe the different states with p-value 60%, Sen > 60% and Pk > 0,6. This signal processing methodology technically contributes to the prediction of anesthesia depth level during Sedation-Analgesia

Libro blanco de diseño para todos en la universidad

Conscientes de que el logro de espacios accesibles para todas las personas depende, en buena medida, de que los profesionales relacionados con la construcción de los entornos físicos y virtuales cuenten con la formación necesaria para diseñar proyectos no excluyentes, el IMSERSO, la Fundación ONCE y la Coordinadora del Diseño para Todas las Personas, han elaborado un ambicioso proyecto formativo dirigido a los futuros estudiantes universitarios. Entre los objetivos de esta práctica herramienta están, por un lado, concienciar a los estudiantes universitarios de la necesidad de crear entornos respetuosos con la diversidad humana, incluyendo entre éstos al universitario, pero también dotar a quienes serán, futuros y futuras profesionales, de una herramienta que les permita abordar satisfactoriamente la accesibilidad dentro de sus proyectos. Para tal fin, este Libro Blanco incorpora diversos ejemplos de currículum orientado a las licenciaturas de arquitectura, ingeniería informática y psicología. En objetivo último es que en el futuro el concepto de Diseño para Todos forme parte de todos los proyectos relacionados con la actividad humana, dando así cumplimiento a la Resolución del Consejo de Europa sobre esta materia

Near-field interactions between metal nanoparticle surface plasmons and molecular excitons in thin-films: part I: absorption

In this and the following paper (parts I and II, respectively), we systematically study the interactions between surface plasmons of metal nanoparticles (NPs) with excitons in thin-films of organic media. In an effort to exclusively probe near-field interactions, we utilize spherical Ag NPs in a size-regime where far-field light scattering is negligibly small compared to absorption. In part I, we discuss the effect of the presence of these Ag NPs on the absorption of the embedding medium by means of experiment, numerical simulations, and analytical calculations, all shown to be in good agreement. We observe absorption enhancement in the embedding medium due to the Ag NPs with a strong dependence on the medium permittivity, the spectral position relative to the surface plasmon resonance frequency, and the thickness of the organic layer. By introducing a low index spacer layer between the NPs and the organic medium, this absorption enhancement is experimentally confirmed to be a near field effect In part II, we probe the impact of the Ag NPs on the emission of organic molecules by time-resolved and steady-state photoluminescence measurements

Symbolic Dynamics applied to Electroencephalographic signals to Predict Response to Noxious Stimulation during Sedation-Analgesia

The level of sedation in patients undergoing medical procedures evolves continuously since the effect of the anesthetic and analgesic agents is counteracted by noxious stimuli. The monitors of depth of anesthesia, based on the analysis of the electroencephalogram (EEG), have been progressively introduced into the daily practice to provide additional information about the state of the patient. However, the quantification of analgesia still remains an open problem. In this project, a methodology based on non-linear techniques signal processing algorithms was developed and applied to the electroencephalogram (EEG) for predicting responses to noxious stimulation during Sedation-Analgesia. Two types of stimuli were performed by the anesthesiologist during the surgery sessions, RSS (Ramsay Sedation Scale) and GAG (gag reflex). These sedation scales are considered gold standard. In this work, the scope of the project includes: EEG preprocessing, processing and analysis of the mentioned signals. The methodology included an EEG signal preprocessing, a time-domain and frequency-domain analysis, the development and application of non-linear techniques, a statistical analysis and finally the validation of the results. Symbolic dynamics methodology, already applied to other kind of signals, was used as a non-linear technique. The aim was to extract a set of patterns from the EEG obtained through two proposed non-linear algorithms. The symbolic dynamics consists of the transformation of the time signal in a series of symbols by an algorithm. From these new series, words of three symbols were constructed with one symbol delay and their occurrence probability was evaluated in the signals variables. Base on this, the Shannon and Rényi entropies were applied to estimate the complexity of the distribution of the variables. Moreover, thresholds on probabilities were used to construct new variables. The analysis was applied to the EEG filtered according to the characteristic frequency bands (EEG rhythms). The parameters involved in the algorithms were statistically adjusted in order to better characterize the nociceptive response. Variables obtained from linear and non-linear methodologies were submitted to a statistical analysis using a nonparametric test and a linear discriminant analyses to assess the quality of the classification. The leaving-one-out method was used as validation criteria. New defined variables were able to describe the different states with p-value 60%, Sen > 60% and Pk > 0,6. This signal processing methodology technically contributes to the prediction of anesthesia depth level during Sedation-Analgesia

Superimposed vibration on suspended push-ups

Background Superimposition of vibration has been proposed in sports training using several devices and methods to enhance muscle activation and strength adaptations. Due to the popularity of suspension training, vibration systems have recently been developed to increase the effects of this training method. The present cross-sectional study aims to examine the effects of superimposing vibration on one of the most popular exercises in strength and conditioning programs: push-ups. Methods Twenty-eight physically active men and women executed push-ups in three suspended conditions (non-vibration, vibration at 25 Hz, and vibration at 40 Hz). OMNI-Res scale was registered, and surface electromyographic signals were measured for the activity of the right and left external oblique, anterior deltoid, triceps brachii, sternal, and clavicular heads of the pectoralis major. Results A linear mixed model indicated a significant fixed effect for vibration at 25 Hz and 40 Hz on muscle activity. Suspended push-ups with superimposed vibration (25 Hz and 40 Hz) showed a significant higher activity on left (25 Hz: p = 0.036, d = 0.34; 40 Hz: p = 0.003, d = 0.48) and right external oblique (25 Hz: p = 0.004, d = 0.36; 40 Hz: p = 0.000, d = 0.59), anterior deltoid (25 Hz: p = 0.032, d = 0.44; 40 Hz: p = 0.003, d = 0.64), and global activity (25 Hz: p = 0.000, d = 0.55; 40 Hz: p = 0.000, d = 0.83) compared to non-vibration condition. Moreover, OMNI-Res significant differences were found at 25 Hz (6.04 ± 0.32, p = 0.000 d = 4.03 CI = 3.27, 4.79) and 40 Hz (6.21 ± 0.36 p = 0.00 d = 4.29 CI = 3.49, 5.08) compared to the non-vibration condition (4.75 ± 0.32). Conclusion Superimposing vibration is a feasible strategy to enhance the muscle activity of suspended push-ups

Libro blanco de diseño para todos en la universidad

Conscientes de que el logro de espacios accesibles para todas las personas depende, en buena medida, de que los profesionales relacionados con la construcción de los entornos físicos y virtuales cuenten con la formación necesaria para diseñar proyectos no excluyentes, el IMSERSO, la Fundación ONCE y la Coordinadora del Diseño para Todas las Personas, han elaborado un ambicioso proyecto formativo dirigido a los futuros estudiantes universitarios. Entre los objetivos de esta práctica herramienta están, por un lado, concienciar a los estudiantes universitarios de la necesidad de crear entornos respetuosos con la diversidad humana, incluyendo entre éstos al universitario, pero también dotar a quienes serán, futuros y futuras profesionales, de una herramienta que les permita abordar satisfactoriamente la accesibilidad dentro de sus proyectos. Para tal fin, este Libro Blanco incorpora diversos ejemplos de currículum orientado a las licenciaturas de arquitectura, ingeniería informática y psicología. En objetivo último es que en el futuro el concepto de Diseño para Todos forme parte de todos los proyectos relacionados con la actividad humana, dando así cumplimiento a la Resolución del Consejo de Europa sobre esta materia