Effect of gamets aging on their activation and fertilizability in zebrafish (Danio rerio)

El pez cebra es un modelo importante para investigación en biomedicina. En este contexto, la fertilizabilidad y desarrollo normal embrionario de semen y huevos de pez cebra de la estirpe gold, fue reevaluada después de ser conservados durante distintos tiempos a 8 ºC en un medio modificado (medio Hanks' con 1.5g BSA y 0.1g ClNa; 320 mOsm, pH 7.4).Cardona Costa, J. (2009). Effect of gamets aging on their activation and fertilizability in zebrafish (Danio rerio). http://hdl.handle.net/10251/14315Archivo delegad

Common mode feedback analysis for EIT systems with distributed current sources

The use of differential voltage measurements is widely used in EIT instruments. Instrumentation amplifiers are always affected by common mode voltages at their input. These voltages may have different origins, being the current sources and multiplexers the ones which contribute the most. However, even considering ideal current sources and multiplexers, some amount of common mode voltage will always be present due to the measurement principle. Errors produced by common mode voltages are very difficult to calibrate because they depend on the object being measured. At low frequencies it is easy to design instrumentation amplifiers with high CMRR values, but common mode voltages are also high, mostly because of unbalances in electrode impedances. At higher frequencies common mode voltages are smaller, but the CMRR of the amplifiers also decreases. Common mode feedback (CMF) to reduce common mode voltages has been largely used in EIT systems. There is a good theoretical understanding of CMF for systems using a single current source and a demultiplexer. However there is a new class of instruments which use distributed current sources. In these systems CMF is actually used to change the inherent unbalance among current sources instead of being applied to the output of the current source. We present a theoretical analysis of this new CMF technique and the results obtained when applying it to our latest EIT systemPostprint (published version

Performance assessment of EIT measurement systems

EIT acquisition systems, when regarded as measuring instruments, can be characterized by their inherent characteristics: reproducibility, repeatability and discrimination. The ultimate limit to all three is noise, whether long-term or short-term noise. In addition, for some applications accuracy can also play a role, although accuracy is not an inherent characteristic and requires a known test object to be defined. Because EIT systems are multichannel instruments and the information of all channels is being combined to produce an image, a procedure to standardize the performance assessment must be set up in order to allow for meaningful comparison of different systems or different settings in the same system. We propose the use of three parameters defined long ago but scarcely used among EIT systems designers: SER (Systematic Error Ratio), NER (Noise Error Ratio) and RER (Reciprocity Error Ratio). We applied these definitions to our latest EIT instruments, TIE5-sys, in a wide frequency range and with different settings in configurable acquisition parameters and provide the interpretation of the results obtained in terms of reproducibility, repeatability and discrimination. We also comment on the tradeoffs that show up when using the usual definition for these figuresPostprint (published version

Informe sobre les campanyes d'anellament d'aucells a les Balears, 1996

Abstract not availabl

Accessibility tool to improve the communication of people with hearing impairment in social environments of virtual reality

Trabajo de Fin de Grado en Desarrollo de Videojuegos, Facultad de Informática UCM, Departamento de Ingeniería del Software e Inteligencia Artificial, Curso 2021/2022.La realidad virtual ha cambiado mucho en los últimos años. En sus inicios se trataba de un producto enfocado a investigadores y entusiastas, pero esos primeros kits de desarrollo han dado paso a productos enfocados al público general con varias generaciones de fabricación que han dado vida a un sector con cada vez más empresas. HTC, Valve, Sony, HP, Samsung y muchos otros se han unido a la carrera iniciada por Oculus. Hoy podemos encontrar dispositivos tan potentes como Quest 2 en los escaparates de grandes superficies a precios muy asequibles. Muchas han sido las mejoras experimentadas gracias a la evolución de esta tecnología, todas encaminadas a proporcionar una inmersión más profunda. Una mayor tasa de refresco evita los mareos, se alcanzan resoluciones que aspiran a eliminar el efecto de rejilla, los sistemas de sonido integrados permiten experimentar un sonido tridimensional, etc. Se trata de una ventana a nuevos mundos virtuales que explorar, interactuando con todo lo que se encuentra a través de nuestro avatar. Es especialmente importante poder relacionarse con otras personas en entornos sociales, como son muchos videojuegos, donde la comunicación entre usuarios es fundamental para disfrutar y conseguir mejores resultados. En medio de esta frenética carrera tecnológica no debemos olvidar a aquellas personas que no tienen fácil acceso a estas experiencias. En este trabajo se presenta el desarrollo de una herramienta que facilita la comunicación de personas con dificultades auditivas, permitiendo la comunicación mediante traducción de algunos signos o de la voz a texto plano, de modo natural y sin perjudicar en exceso la inmersión. Se puede acceder al código de la aplicación a través del repositorio público (Antonio Cardona, 2022).Virtual Reality scene has changed a lot in the last few years. In it’s begginings it was a product targeted to enthusiasts and researchers, but those first development kits brought a new line of products targeted to the general public. Generation by generation this sector has come to life with more and more investors and manufacturers. HTC, Valve, Sony, HP, Samsung and many others joined this race started by Oculus. Today it’s easy to find powerful devices like Quest 2 in any mall for an afordable price. Many improvements came with the evolution of this technology, aiming for a deeper user inmersion. A higher refresh rate prevents dizziness, display resolutions are reaching a point where screen effect is close to dissapear, integrated sound systems give a better 3D sound awareness. Step by step technology is reaching a better inmersion. This is about providing an access window to new virtual worlds to explore and interact with through our avatar. It is of most interest to give the users the ability to communicate with others in these new social environments, being videogames or just social aplications, so everyone can enjoy and interact seamlessly. Developers can not afford to forget about those who can’t have an easy access to this experiences. This work develops a tool that facilitates communication for people with Hearing Impairment, enabling communication through the translation of voice to text and sign language to text. The code can be found in this repository (Antonio Cardona, 2022).Depto. de Ingeniería de Software e Inteligencia Artificial (ISIA)Fac. de InformáticaTRUEunpu

Electroactivación de oocitos de pez cebra (Danio rerio)

[ES] El mejor tratamiento de electroactivación (B3) para oocitos de pez cebra supuso un 43% de activación frente al 18% cuando el estímulo es solo el contacto con agua[EN] In zebrafish, initial egg activation by water after being discharged from the ovarian stroma is followed by normal cleavages only in inseminated eggs. When sperm (genetically active or not) is not used as activating agent, reproductive techniques (as either nuclear transplant or intracytoplasmic sperm injection are ineff icient. In this work, three experiments of egg activation by electric stimuli were performed: In the first, six activation treatments were compared (Voltage × Pulses: 2.76 × 1; 2.76 × 2; 2.76 × 3 and 5.40 × 1; 5.40 × 2; 5.40 × 3). The group 5.40 × 3 showed the best results (32% activated). In the second experiment, an electrical treatment of 20 min was carried out. It consisted in a sequence of three equal electrical stimuli every 10 min (of 1 or 3 consecutive direct current square pulses for 20 ¿s each and applied at two voltage levels, 2.76 V or 5.4 V). It was observed that the number of pulses negatively affected the rates of damaged and lysed eggs. Moreover, only the 20 min treatment with the combination of 3 consecutive pulses at 2.76 V showed significant differences with their respective control group (43% vs 18% activated eggs, p < 0.05). In the third experiment, negative effects of egg ageing were observed. In conclusion, the best activation treatment for intact (non manipulated) zebrafish eggs concerns sequence B3. The electro-activation stimulus proposed here would be the only one available once the egg has already been activated by water.Cardona Costa, J.; Perez-Camps, M.; García Ximenez, F. (2011). Electroactivation of zebrafish (danio rerio) eggs. Spanish Journal of Agricultural Research. 9(1):59-65. http://hdl.handle.net/10251/99491S59659

A tecnologia digital e suas possibilidades na educação

Este trabalho de conclusão de curso busca refletir sobre a utilização da tecnologia digital no processo educativo sob uma perspectiva construtivista, observando os principais desafios das instituições de ensino para a aplicação de novos métodos de ensino através de recursos tecnológicos. Em um levantamento bibliográfico, é apresentada uma visão panorâmica das diferentes realidades escolares em que as tecnologias estão sendo incorporadas; em seguida, são tecidas considerações sobre a resistência dos professores para o uso das tecnologias em sala de aula, inclusão digital e as transformações necessárias de alguns elementos do cotidiano pedagógico, como o papel do educador e o planejamento sob a perspectiva da inovação de recursos de ensino.This conclusion of course work reflects upon the use of digital technology in the educational process in a constructivist perspective, noting the main challenges of educational institutions for the implementation of new teaching methods through technological resources. Through literature, we present an overview of different educational situations in which technologies are being incorporated, then, are considerations regarding the teachers' resistance to the use of technology in the classroom, digital inclusion and the changes necessary to some elements of the pedagogical and the role of educator and planning from the perspective of innovation in teaching resources

A tecnologia digital e suas possibilidades na educação

Este trabalho de conclusão de curso busca refletir sobre a utilização da tecnologia digital no processo educativo sob uma perspectiva construtivista, observando os principais desafios das instituições de ensino para a aplicação de novos métodos de ensino através de recursos tecnológicos. Em um levantamento bibliográfico, é apresentada uma visão panorâmica das diferentes realidades escolares em que as tecnologias estão sendo incorporadas; em seguida, são tecidas considerações sobre a resistência dos professores para o uso das tecnologias em sala de aula, inclusão digital e as transformações necessárias de alguns elementos do cotidiano pedagógico, como o papel do educador e o planejamento sob a perspectiva da inovação de recursos de ensino.This conclusion of course work reflects upon the use of digital technology in the educational process in a constructivist perspective, noting the main challenges of educational institutions for the implementation of new teaching methods through technological resources. Through literature, we present an overview of different educational situations in which technologies are being incorporated, then, are considerations regarding the teachers' resistance to the use of technology in the classroom, digital inclusion and the changes necessary to some elements of the pedagogical and the role of educator and planning from the perspective of innovation in teaching resources

Tidal Volume (TV) post-process obtained with electrical impedance tomography on a group of chronic obstructive pulmonary disease (COPD) patients. Use of adjust equations

Equations used to estimate ventilation out of EIT images, validated on healthy volunteers show a significant bias and a larger variance when were applied on a COPD patients group. The differences in estimation values were found to be highly correlated with anthropometric parameters. Two groups of 13 and 4 COPD male patients (FEV1/FVC<70% and FVC ≥ 80%) were used in this study. We have measured different anthropometric parameters like age, weight, height and skinfolds. The EIT system (TIE4sys) and a pneumotach were simultaneously connected to monitor tidal volume. The main anthropometric parameters values of 13 COPD patients were: age: 67±9 years, height: 1.65±0.05 m, weight: 72±11 kg, BMI: 26.4±3.3; and the subscapular skinfold thickness was 23±9mm. The mean tidal volume estimated with TIE4sys and the pneumotach were: 0.580±0.212 L and 0.774±0.173 L r = 0.861 (p<0.01). The mean difference was 0.196±0.096 L (p<0.01). On this group we have found out an adjust equation and we have validated it on an independent group of 4 COPD patients. The equation was Diff=-1478+15.6(weight). The mean tidal volume values obtained with pneumotach and TIE4sys on the second group of COPD patients (M:4) were: 0.798±0.395 L and 0.732±0.327 L. The mean of the differences was 0.066±0.114L. The differences of determinations estimated with pneumotach and TIE4sys can be attributed to changes of anthropometric characteristics like subscapular skinfold.Peer ReviewedPostprint (author’s final draft