Implementation of a Microthruster Using PCBMEMS

This paper describes the implementation of microthrusters using PCBMEMS technology. PCBMEMS is the engineering of MEMS devices based on standard printed circuit board (PCB) technology. The reduced thickness of the copper layers together with the high resolution of the features on a PCB allow the implementation of micrometer-sized devices. A solid fuel microthruster including a tank, detonator and throat has been designed, simulated, manufactured, and tested using this PCBMEMS technology

Neural network monitoring of resistance welding processes

Control of weld quality is one of the most important and complex processes to be carried out on production lines. Neural networks have shown good results in fields such as modelling and control of physical processes. It is suggested in this article that a neural classifier should be used to carry out non‐destructive on‐line analysis. This system has been developed and installed at resistance welding stations. Results confirm the validity of neural networks used for this type of application

Tachinidae (Diptera) del Parque Nacional de La Caldera de Taburiente en La Palma (Islas Canarias)

Data on distribution, abundance and phenology of Tachinidae (Diptera) from the Caldera de Taburiente National Park on La Palma are given, based on systematic Malaise trap and yellow pan trap samples between August 1999 and July 2001. The occurrence of 22 species is proved; all of them were already known from the Canary Islands, but two species (Gonia quadrisetosa and Phytomyptera vaccinii) are recorded from La Palma for the first time. The present paper is a result of the project “Inventory and study of the invertebrate fauna of the Caldera de Taburiente National Park”.Se presentan datos de distribución, abundancia y fenología de Tachinidae (Diptera), obtenidos en el Parque Nacional de la Caldera de Taburiente en La Palma con trampa Malaise y trampa amarilla entre agosto de 1999 y julio de 2001. Han sido recolectadas 22 especies, todas ya conocidas en las Islas Canarias, pero dos especies (Gonia quadrisetosa y Phytomyptera vaccinii) son citas nuevas para La Palma. El presente artículo es un resultado del proyecto “Inventario y estudio de la fauna invertebrada del Parque Nacional de la Caldera de Taburiente”

Movies and TV series fragments in mathematics: Epistemic suitability of instructional designs

There are plenty of books, journals and online sites devoted to the relationship between mathematics and cinema, and its educational applications, whose interest is to explore the pertinence of the instruction processes that can be designed around this resource. Instead of watching a full production, mathematics teachers that include movies and TV series in their classroom sessions, usually show short fragments, so the first step should be to consider these fragments alone to identify the mathematical objects and the involved meanings and representations. For this purpose, we use some theoretical notions from the Onto- Semiotic Approach to research in mathematics education, applying them to three excerpts from a movie and to some typical tasks designed based on them. The analysis of the involved mathematical content allows to reflect about the epistemic suitability of the instruction process, in terms of how aligned they are with the institutional meanings. The results show that it is possible to achieve a high suitability level but, most importantly, that this kind of analysis promotes teacher reflection to design teaching and learning processes

Saber es Hacer: Una Experiencia Innovadora en la Enseñanza de Catastro.

La enseñanza de la asignatura de Catastro en la Escuela Técnica Superior de Ingenieros de Montes y en la Escuela Universitaria de Ingeniería Técnica Forestal ha sufrido modificaciones en cuanto a su metodología pedagógica, de manera que se ha incrementado el índice de recuerdo por parte de los alumnos una vez finalizados sus estudios. Este punto se ha logrado tras aplicar herramientas de análisis estratégico (DAFO) con el fin de detectar debilidades, amenazas, fortalezas y oportunidades que presentaban dichas asignaturas. Una vez descritas éstas, se han diseñado métodos para mejorar la calidad de la docencia en las mismas

Activity Recognition for IoT Devices Using Fuzzy Spatio-Temporal Features as Environmental Sensor Fusion

The IoT describes a development field where new approaches and trends are in constant change. In this scenario, new devices and sensors are offering higher precision in everyday life in an increasingly less invasive way. In this work, we propose the use of spatial-temporal features by means of fuzzy logic as a general descriptor for heterogeneous sensors. This fuzzy sensor representation is highly efficient and enables devices with low computing power to develop learning and evaluation tasks in activity recognition using light and efficient classifiers. To show the methodology's potential in real applications, we deploy an intelligent environment where new UWB location devices, inertial objects, wearable devices, and binary sensors are connected with each other and describe daily human activities. We then apply the proposed fuzzy logic-based methodology to obtain spatial-temporal features to fuse the data from the heterogeneous sensor devices. A case study developed in the UJAmISmart Lab of the University of Jaen (Jaen, Spain) shows the encouraging performance of the methodology when recognizing the activity of an inhabitant using efficient classifiers

Un método optimizado para el análisis cromosómico de ovocitos y cigotos obtenidos mediante técnicas de maduración y fecundación in vitro

Matured bovine oocytes and zygotes obtained by in vitro maturation and fertilization techniques (IVM and IVF) were cytogenetically prepared by using an improved method for chromosome preparations. The method, which involves use of trypsinizedhypotonic solution plus a vortex-agitated system and very cold two-step fixation process, contributes to weaken the zona pellucida and allows the swelling of oocytes and zygotes which helps the subsequent spreading of the chromosomes. This method permits to obtain preparations of good quality for examining the number and morphology of the chromosomes of oocytes and zygotes for any meiotic and mitotic stage.Se logró optimizar un método rápido para analizar citogenéticamente ovocitos y cigotos de bovino obtenidos mediante técnicas de maduración y fecundación in vitro (MIV y FIV). El método, el cual utiliza una solución hipotónica con tripsina, un sistema de agitación mediante vortex y un sistema doble de fijación en frío, contribuye a eliminar fácilmente la zona pelúcida y a hinchar a los ovocitos y cigotos favoreciendo posteriormente la extensión de los cromosomas. Este método permite obtener preparaciones de muy buena calidad para el análisis tanto del número como de la morfología de los cromosomas de los ovocitos y cigotos en cualquier estadío meiótico y mitótico

Influencia de la insulina bovina y humana sobre los índices de maduración, fecundación y división in vitro de ovocitos de bovino

The present study was carried out to determine the effects of supplementation of the maturation media with human or bovine insulin on in vitro maturation, fertilization and cleavage rates of bovine oocytes. Cumulus-intact bovine oocytes were cultured in a maturation medium (TCM-199 containing 10 percent fetal calf serum) with or without human or bovine insulin supplementation (10 mg/ml). For the bovine insulin supplement, the maturation (80.3 percent), fertilization (61.3 percent) and cleavage (55.3 percent) rates were significantly higher (p<0.05) than those obtained in the control group (70.1; 50.1 and 42.5 percent respectively). Thus, the percentages of cleavaged ova obtained in presence of human or bovine insulin (54.8 and 55.3 percent respectively) were significantly higher (p<0.05) than those observed in control group (42.5 percent). No difference was found among human and bovine insulin treatments. These results demonstrate that the addition of human or bovine insulin to the maturation medium increased the percentages of matured oocyte, increasing the subsequent fertilization and cleavage rates of bovine oocytes in vitro.Se realizó un estudio para determinar los efectos de la suplementación del medio de maduración con insulina humana o bovina sobre los índices de maduración, fecundación y división in vitro de ovocitos de bovino. Ovocitos de bovino se cultivaron en medio de maduración (TCM-199 conteniendo 10 p.100 de suero de ternero fetal) con o sin insulina humana o bovina (10 mg/ml). Para la insulina bovina, los índices de maduración (80,3 p.100), fecundación (61,3 p.100) y división (55,3 p.100) fueron superiores significativamente (p<0,05) que aquellos obtenidos por el grupo control (70,1; 50,1 y 42,5 p.100 respectivamente). Además, los porcentajes de óvulos divididos obtenidos en presencia de insulina humana o bovina (54,8 y 55,3 p.100 respectivamente), fueron superiores significativamente (p<0,05) en comparación con los obtenidos por el grupo control (42,5 p.100). No se apreciaron diferencias significativas entre los tratamientos con insulina humana y bovina. Estos resultados ponen de manifiesto que la adición de insulina humana o bovina al medio de maduración incrementa los porcentajes de ovocitos maduros, mejorando posteriormente los índices de fecundación y división de ovocitos de bovino in vitro