Extended ageing time and temperature effects on quality of sub-primal cuts of boxed beef

[EN]Most of the information indicating ageing improves tenderness has been collected on the loin and rib-eye muscles over relatively short ageing times, assuming that all muscles will react similarly. In the present study, the effect of extended ageing times on instrumental texture (56 d) and sensory characteristics (42 d) of six different beef sub-primals [striploin (SL), inside round (IR), outside round (OR), eye of round (ER), blade eye (BE) and chuck tender (CT)] was studied. The effects of two ageing temperatures (1and 58C) were also compared. In general, ageing increased tenderness (P<0.05) of SL, BE, ER and CT sub-primals, although BE shear force increased after 42 d of ageing. On the other hand, ageing had no effect on IR tenderness (P<0.05) and resulted in a decrease in tenderness of OR (P<0.05) until day 35, with a later increase after 42 d of ageing. Increasing ageing temperature (58C) had limited effect on tenderness, but ageing time and temperature increases led to lower flavour and higher off-flavour intensity (P<0.05) of the studied sub-primals. These results suggest that cutspecific maximum ageing times and rigid adherence to temperature maximums would be of benefit to optimize postslaughter processes and meat quality

Early Functional Deficit and Microglial Disturbances in a Mouse Model of Amyotrophic Lateral Sclerosis

11 p.

Características antropométricas, condición física y velocidad de lanzamiento en balonmano de élite y amateur

166 p.

Bihotz-biriketako berpizte masajeak EKG-an eta bular-inpedantzian eragindako interferentziaren azterketa

[EU]Proiektu honetan bihotz-biriketako berpizte masajearen bular-sakadek elektrokardiograman eta bular-inpedantziaren seinaleetan eragindako interferentziaren azterketa egiten da. Helburu nagusia bi interferentzia hauen arteko erlazioa aztertzea da, horretarako tresna garatuz. Erlazio hau definitzeak interferentziaren eragina txikitzeko modua aurkitzen lagunduko luke, eta honek berpizteko aukerak handituko lituzke. Proiektua gauzatzeko ospitalez kanpoko geldialdien erregistro multzo batetik abiatuta datu-base propioa garatu da ezarritako irizpide batzuk jarraituz. Datu-base berri hau 37 pazienteren 237 mozketak osatzen dute, 10 segundotako luzera minimoarekin non pazienteek asistolia bitarteko kanpoko bular masajea jasotzen duten. Bestalde, interferentzia ezaugarritzeko interfaze grafiko bat garatu da, elektrokardiograma eta bular-inpedantziaren seinaleak denboran eta maiztasunean erakutsi eta hauen parametro esanguratsuak automatikoki zein eskuz ateratzeko aukera ematen duena. Parametroak seinaleen sakada bakoitzeko maximo eta minimoak, beraien kokapenak eta oinarrizko maiztasuna, bere harmonikoak eta hauen anplitudeak dira. Tresna hau erabiliz aipatutako datu-baseko episodioen prozesaketa egin da. Bukatzeko, lortutako emaitzak tratatzeko bigarren interfaze grafiko bat garatu da, non emaitzen banaketa estatistikoa eta hauen arteko erlazio lineala aztertzen diren. Proiektuaren ekarpen nagusia, beraz, bihotz-biriketako berpizte masajeak eragindako interferentzia aztertzeko tresna ahaltsuaren garapena da, jatorri desberdineko bestelako berpizte episodioak aztertzeko ere balio duena.

Plataforma de investigación en el ámbito de la resucitación cardio-pulmonar basada en un maniquí de entrenamiento sensorizado

[ES]Hoy en día las muertes por parada cardiorrespiratoria superan en número a otras más mediáticas como aquellas que se producen por incendios o en accidentes de tráfico, y sin embargo su repercusión es mucho menor. Este hecho debe ser motivo de preocupación ya que, con una correcta formación de la población en materia de resucitación cardíaca, muchas de estas muertes podrían ser evitadas. Con el objetivo de reducir estas estadísticas han surgido multitud de estudios y proyectos de investigación consistentes en tratar de mejorar las herramientas disponibles tanto para personal sanitario como no sanitario. En este marco se encuadra el proyecto presentado en este documento, consistente en la sensorización de un maniquí de entrenamiento para episodios de parada cardiorrespiratoria, el cual ofrecerá la posibilidad de analizar con detalle el artifact o interferencia generada por el rescatador sobre el paciente en el momento de efectuar la maniobra de resucitación, así como la interferencia causada por el contacto electrodo-piel. Paralelamente podrá ser utilizado como mero instrumento de entrenamiento para posibles situaciones reales. El porqué de la utilización de este tipo de maniquíes reside principalmente en la imposibilidad de emplear personas debido a las posibles lesiones torácicas que pueden ocurrir por las compresiones realizadas. Finalmente debe citarse el hecho de que no es imprescindible tener conocimientos médicos para poder aplicar las técnicas básicas de resucitación cardíaca, acción que incrementa las posibilidades de supervivencia de un paciente de manera excepcional, ya que cada minuto que pasa desde la parada cardiorrespiratoria la probabilidad de supervivencia disminuye en un porcentaje significativamente elevado. Tomando como base lo descrito hasta ahora, en este documento se detalla la solución técnica de la sensorización de un maniquí genérico para la adquisición de las señales de fuerza de compresión, aceleración sufrida por el pecho en tres ejes ortogonales, profundidad de compresión, impedancia entre los dos electrodos colocados sobre el pecho del paciente y señal electrocardiográfica emitida por el corazón; además, se incluye la posibilidad de inyectar una señal electrocardiográfica previamente grabada. La base de registros obtenida de estos ensayos podrá ser utilizada posteriormente para su análisis, ya que su similitud con señales extraídas en un caso real es máxima.

Spinal circuits can accommodate interaction torques during multijoint limb movements

The dynamic interaction of limb segments during movements that involve multiple joints creates torques in one joint due to motion about another. Evidence shows that such interaction torques are taken into account during the planning or control of movement in humans. Two alternative hypotheses could explain the compensation of these dynamic torques. One involves the use of internal models to centrally compute predicted interaction torques and their explicit compensation through anticipatory adjustment of descending motor commands. The alternative, based on the equilibrium-point hypothesis, claims that descending signals can be simple and related to the desired movement kinematics only, while spinal feedback mechanisms are responsible for the appropriate creation and coordination of dynamic muscle forces. Partial supporting evidence exists in each case. However, until now no model has explicitly shown, in the case of the second hypothesis, whether peripheral feedback is really sufficient on its own for coordinating the motion of several joints while at the same time accommodating intersegmental interaction torques. Here we propose a minimal computational model to examine this question. Using a biomechanics simulation of a two-joint arm controlled by spinal neural circuitry, we show for the first time that it is indeed possible for the neuromusculoskeletal system to transform simple descending control signals into muscle activation patterns that accommodate interaction forces depending on their direction and magnitude. This is achieved without the aid of any central predictive signal. Even though the model makes various simplifications and abstractions compared to the complexities involved in the control of human arm movements, the finding lends plausibility to the hypothesis that some multijoint movements can in principle be controlled even in the absence of internal models of intersegmental dynamics or learned compensatory motor signals.

Physiological modules for generating discrete and rhythmic movements: action identification by a dynamic recurrent neural network

In this study we employed a dynamic recurrent neural network (DRNN) in a novel fashion to reveal characteristics of control modules underlying the generation of muscle activations when drawing figures with the outstretched arm. We asked healthy human subjects to perform four different figure-eight movements in each of two workspaces (frontal plane and sagittal plane). We then trained a DRNN to predict the movement of the wrist from information in the EMG signals from seven different muscles. We trained different instances of the same network on a single movement direction, on all four movement directions in a single movement plane, or on all eight possible movement patterns and looked at the ability of the DRNN to generalize and predict movements for trials that were not included in the training set. Within a single movement plane, a DRNN trained on one movement direction was not able to predict movements of the hand for trials in the other three directions, but a DRNN trained simultaneously on all four movement directions could generalize across movement directions within the same plane. Similarly, the DRNN was able to reproduce the kinematics of the hand for both movement planes, but only if it was trained on examples performed in each one. As we will discuss, these results indicate that there are important dynamical constraints on the mapping of EMG to hand movement that depend on both the time sequence of the movement and on the anatomical constraints of the musculoskeletal system. In a second step, we injected EMG signals constructed from different synergies derived by the PCA in order to identify the mechanical significance of each of these components. From these results, one can surmise that discrete-rhythmic movements may be constructed from three different fundamental modules, one regulating the co-activation of all muscles over the time span of the movement and two others elliciting patterns of reciprocal activation operating in orthogonal directions.

Physiological modules for generating discrete and rhythmic movements: Component analysis of EMG signals

A central question in Neuroscience is that of how the nervous system generates the spatiotemporal commands needed to realize complex gestures, such as handwriting. A key postulate is that the central nervous system (CNS) builds up complex movements from a set of simpler motor primitives or control modules. In this study we examined the control modules underlying the generation of muscle activations when performing different types of movement: discrete, point-to-point movements in eight different directions and continuous figure-eight movements in both the normal, upright orientation and rotated 90 degrees. To test for the effects of biomechanical constraints, movements were performed in the frontal-parallel or sagittal planes, corresponding to two different nominal flexion/abduction postures of the shoulder. In all cases we measured limb kinematics and surface electromyographic activity (EMB) signals for seven different muscles acting around the shoulder. We first performed principal component analysis (PCA) of the EMG signals on a movement-by-movement basis. We found a surprisingly consistent pattern of muscle groupings across movement types and movement planes, although we could detect systematic differences between the PCs derived from movements performed in each sholder posture and between the principal components associated with the different orientations of the figure. Unexpectedly we found no systematic differences between the figute eights and the point-to-point movements. The first three principal components could be associated with a general co-contraction of all seven muscles plus two patterns of reciprocal activatoin. From these results, we surmise that both "discrete-rhythmic movements" such as the figure eight, and discrete point-to-point movement may be constructed from three different fundamental modules, one regulating the impedance of the limb over the time span of the movement and two others operating to generate movement, one aligned with the vertical and the other aligned with the horizontal.

Diseño y evaluación de métodos de supresión del artefacto causado en el ECG por las compresiones torácicas proporcionadas por el dispositivo mecánico LUCAS.

[Es]En este proyecto se analizan el diseño y la evaluación de dos métodos para la supresión de la interferencia generada por las compresiones torácicas proporcionadas por el dispositivo mecánico LUCAS, en el electrocardiograma (ECG) durante el masaje de resucitación cardiopulmonar. El objetivo es encontrar un método que elimine el artefacto generado en el ECG de una manera efectiva, que permita el diagnóstico fiable del ritmo cardiaco. Encontrar un método eficaz sería de gran ayuda para no tener que interrumpir el masaje de resucitación para el análisis correcto del ritmo cardiaco, lo que supondría un aumento en las probabilidades de resucitación. Para llevar a cabo el proyecto se ha generado una base de datos propia partiendo de registros de paradas cardiorrespiratorias extra-hospitalarias. Esta nueva base de datos contiene 410 cortes correspondientes a 86 pacientes, siendo todos los episodios de 30 segundos de duración y durante los cuales el paciente, recibe masaje cardiaco. Por otro lado, se ha desarrollado una interfaz gráfica para caracterizar los métodos de supresión del artefacto. Esta, muestra las señales del ECG, de impedancia torácica y del ECG tras eliminar el artefacto en tiempo. Mediante esta herramienta se han procesado los registros aplicando un filtro adaptativo y un filtro de coeficientes constantes. La evaluación de los métodos se ha realizado en base a la sensibilidad y especificidad del algoritmo de clasificación de ritmos con las señales ECG filtradas. La mayor aportación del proyecto, por tanto, es el desarrollo de una potente herramienta eficaz para evaluar métodos de supresión del artefacto causado en el ECG por las compresiones torácicas al realizar el masaje de resucitación cardiopulmonar, y su posterior diagnóstico. Un instrumento que puede ser implementado para analizar episodios de resucitación de cualquier tipo de procedencia y capaz de integrar nuevos métodos de supresión del artefacto.

Sistema para la detección automática de pulso y respiración en la señal de aceleración.

ES]El proyecto descrito en este documento consiste en la investigación sobre la viabilidad de detección automática de pulso y respiración a partir de la señal de aceleración, medida mediante un acelerómetro posicionado bien en la carótida o en el pecho del paciente. El motivo de la utilización de la aceleración está principalmente en el bajo costo y por la tecnología sencilla de los acelerómetros. En este documento se explica cómo se ha montado una plataforma para la adquisición de las señales de aceleración y el electrocardiograma emitido por el corazón, en sujetos sanos. Con la base de señales adquirida se ha diseñado un método basado en el dominio de la frecuencia para detectar la presencia de pulso y respiración. Los resultados son prometedores y confirman la posibilidad de desarrollar estos detectores. Las herramientas desarrolladas podrán ser utilizadas para análisis futuros y para seguir avanzando en este estudio.

Análisis de la interferencia inducida en el electrocardiograma y señal de impedancia por compresiones torácicas sobre un maniquí.

[EN]This paper presents a project within that research field. The project consists on the development of an experimental environment comprised by a sensorized practice manikin and a management software system. Manikin model allows the simulation of cardiac arrest episodes on laboratory settings. The management software system adds the capacity to compute and analyze the characteristics of the artifact induced on the electrocardiogram and the thoracic impedance signals by chest compressions during cardiopulmonary resuscitation due to variations of the electrode-skin interface. The main reason for choosing this kind of model is the impossibility to use real people because of the risk of thoracic injuries during chest compression. Moreover, this platform could be used for training in reanimation techniques for real situations. Even laypeople with minimal training can perform cardiopulmonary resuscitation. This can reduce the response time to an emergency while the healthcare personnel arrives, which is key to improve outcomes, since with every minute the chances of survival decrease approximately 10%. It is not necessary to have medical knowledge to perform cardiopulmonary resuscitation, which could increase chances of survival for a patient with an early reanimation since In this context, this paper details the technique solution for the manikin sensorisation to acquire the electrocardiogram, the impedance signal measured between the defibrillation pads placed on the patient’s chest, the compression depth, the compression force and the acceleration experienced by the chest in the three orthogonal axes. Moreover, it is possible to inject a previously recorded electrocardiogram signal.

Predictive score for mortality in patients with COPD exacerbations attending hospital emergency departments

Background: Limited information is available about predictors of short-term outcomes in patients with exacerbation of chronic obstructive pulmonary disease (eCOPD) attending an emergency department (ED). Such information could help stratify these patients and guide medical decision-making. The aim of this study was to develop a clinical prediction rule for short-term mortality during hospital admission or within a week after the index ED visit. Methods: This was a prospective cohort study of patients with eCOPD attending the EDs of 16 participating hospitals. Recruitment started in June 2008 and ended in September 2010. Information on possible predictor variables was recorded during the time the patient was evaluated in the ED, at the time a decision was made to admit the patient to the hospital or discharge home, and during follow-up. Main short-term outcomes were death during hospital admission or within 1 week of discharge to home from the ED, as well as at death within 1 month of the index ED visit. Multivariate logistic regression models were developed in a derivation sample and validated in a validation sample. The score was compared with other published prediction rules for patients with stable COPD. Results: In total, 2,487 patients were included in the study. Predictors of death during hospital admission, or within 1 week of discharge to home from the ED were patient age, baseline dyspnea, previous need for long-term home oxygen therapy or non-invasive mechanical ventilation, altered mental status, and use of inspiratory accessory muscles or paradoxical breathing upon ED arrival (area under the curve (AUC) = 0.85). Addition of arterial blood gas parameters (oxygen and carbon dioxide partial pressures (PO2 and PCO2)) and pH) did not improve the model. The same variables were predictors of death at 1 month (AUC = 0.85). Compared with other commonly used tools for predicting the severity of COPD in stable patients, our rule was significantly better. Conclusions: Five clinical predictors easily available in the ED, and also in the primary care setting, can be used to create a simple and easily obtained score that allows clinicians to stratify patients with eCOPD upon ED arrival and guide the medical decision-making process.

Analysis of the Response Speed of Musculature of the Knee in Professional Male and Female Volleyball Players

The aim of this study was to evaluate the normalized response speed (Vrn) of the knee musculature (flexor and extensor) in high competitive level volleyball players using tensiomyography (TMG) and to analyze the muscular response of the vastus medialis (VM), rectus femoris (RF), vastus lateralis (VL), and biceps femoris (BF) in accordance with the specific position they play in their teams. One hundred and sixty-six players (83 women and 83 men) were evaluated. They belonged to eight teams in the Spanish women's superleague and eight in the Spanish men's superleague. The use of Vrn allows avoiding possible sample imbalances due to anatomical and functional differences and demands. We found differences between Vrn in each of the muscles responsible for extension (VM, RF, and VL) and flexion (BF) regardless of the sex. Normalized response speed differences seem to be larger in setters, liberos and outside players compared to middle blockers and larger in males when compared to females. These results of Vrn might respond to the differences in the physical and technical demands of each specific position, showing an improved balance response of the knee extensor and flexor musculature in male professional volleyball players.