675 research outputs found
New data about Early Cretaceous Ginkgoales from southwestern Europe (middle-late Albian of Spain)
We present in this work a leaf-type corresponding to the Ginkgoales genus Sphenobaiera recorded in deposits from the middle-upper Albian (Lower Cretaceous) of northeastern Spain. The fossil leaf shows a widely dissected lamina that forks regularly six times ending at the apex in sixty-four tiny wedge-shaped segments, which are characters similar to those in Sphenobaiera pecten from the Middle Jurassic of England. The exceptional preservation of this fossil leaf, which preserves all segments in connection with its base, in addition to taphonomical and sedimentological data, indicates a nearby location for the parent plant, which grew near the shores of a tidally-influenced fluvial environment. A palaeoenvironmental reconstruction of the sub-environments where the different types of Ginkgoales known from the Albian of northeastern Spain developed is also presented. The presence of a variety of different types of Ginkgoales in middle-upper Albian deposits from Spain represents a new contribution to the knowledge of the palaeoenvironmental conditions for this region of southwestern Eurasia during the late Early Cretaceous
Probabilistic CTL* : the deductive way
Complex probabilistic temporal behaviours need to be guaranteed in robotics and various other control domains, as well as in the context of families of randomized protocols. At its core, this entails checking infinite-state probabilistic systems with respect to quantitative properties specified in probabilistic temporal logics. Model checking methods are not directly applicable to infinite-state systems, and techniques for infinite-state probabilistic systems are limited in terms of the specifications they can handle.
This paper presents a deductive approach to the verification of countable-state systems against properties specified in probabilistic CTL ∗ , on models featuring both nondeterministic and probabilistic choices. The deductive proof system we propose lifts the classical proof system by Kesten and Pnueli to the probabilistic setting. However, the soundness arguments are completely distinct and go via the theory of martingales. Completeness results for the finite-state case and an infinite-state example illustrate the effectiveness of our approach
¿Qué hay dentro de la cueva? : una experiencia multisensorial para trabajar las ciencias con alumnos de Educación Infantil
Este trabajo implica el diseño, planificación, implementación al aula y análisis de una experiencia multisensorial donde se trabajan contenidos cientÃficos dirigida a alumnos de Educación Infantil (EI). El objetivo es doble: en primer lugar educar sensorialmente a los niños mediante una exploración en la que utilizan los cinco sentidos de manera simultánea y experimentar las sensaciones que ofrece la manipulación de materiales naturales. En segundo lugar, que los maestros en activo, al analizar la experiencia, evalúen la necesidad de trabajar la educación sensorial en ciencias y reconozcan su insustituible valor didáctico en el proceso de enseñanza-aprendizaje.Este trabajo implica el diseño, planificación, implementación al aula y análisis de una experiencia multisensorial donde se trabajan contenidos cientÃficos dirigida a alumnos de Educación Infantil (EI). El objetivo es doble: en primer lugar educar sensorialmente a los niños mediante una exploración en la que utilizan los cinco sentidos de manera simultánea y experimentar las sensaciones que ofrece la manipulación de materiales naturales. En segundo lugar, que los maestros en activo, al analizar la experiencia, evalúen la necesidad de trabajar la educación sensorial en ciencias y reconozcan su insustituible valor didáctico en el proceso de enseñanza-aprendizaje
Alteraciones testiculares más frecuentes en ganado ovino
Los testÃculos, albergados en el escroto, pueden presentar alteraciones fácilmente detectables mediante la exploración clÃnica de estas gónadas. Entre las más frecuentes se encuentran la citroquidia, microquidia, hipoplasia, atrofia testicular, orquitis y epididimitis, hidrocele, hematocele y variocele y hernia escrotal
Espacios artÃsticos para vivir las ciencias en Educación Infantil
Este trabajo presenta el diseño, planificación, implementación en el aula y análisis de una secuencia de ocho sesiones de instalación artÃstica que posibilitan el aprendizaje de contenidos cientÃficos en el alumnado de Educación Infantil (EI). Se analiza desde una perspectiva descriptiva cómo las actividades les permiten experimentar con los objetos que configuran cada instalación para descubrir los procesos cientÃficos que implican sus acciones, verbalizarlos, pensar en lo que ocurre y conocer de este modo la ciencia que hay a nuestro alrededor.
This article presents the design, planning, classroom implementation and analysis of a sequence of eight artistic installation sessions that make it possible for early-childhood pupils to learn scientific content. Using a descriptive perspective, the study analyses how the activities allow researchers to experiment with each installation's object to discover the scientific processes involved in their actions, verbalise them, think about what is happening and thus know the science around us
A new isoetalean microsporophyll from the latest albian of northeastern Spain: Diversity in the development and dispersal strategies of microspores
In this paper well-preserved isoetalean microsporophyll, containing in situ microspores, is described from the uppermost part of the Utrillas Formation (latest Albian) in Teruel Province, northeastern Spain. Similar but dispersed microspores were described previously as Peromonolites. Fossil plant impressions and compressions including the sporophyll lamina and microsporangium are referred to the fossil genus Isoetites. Although Isoetes-like megafossil remains, often with in situ or associated megaspores, are known from quite a few Cretaceous sites, and dispersed microspores are known, the presence of intact microsporangia is rare. Herein we suggest that microsporangia may have dispersed in masses, possibly representing a new unknown strategy in microspore dispersal in this group of plants
Flow and clogging of a sheep herd passing through a bottleneck
We present an experimental study of a flock passing through a narrow door. Video monitoring of daily routines in a farm has enabled us to collect a sizable amount of data. By measuring the time lapse between the passage of consecutive animals, some features of the flow regime can be assessed. A quantitative definition of clogging is demonstrated based on the passage time statistics. These display broad tails, which can be fitted by power laws with a relatively large exponent. On the other hand, the distribution of burst sizes robustly evidences exponential behavior. Finally, borrowing concepts from granular physics and statistical mechanics, we evaluate the effect of increasing the door size and the performance of an obstacle placed in front of it. The success of these techniques opens new possibilities regarding their eventual extension to the management of human crowds
Diagnostic imaging techniques of the respiratory tract of sheep
Diagnostic imaging techniques are very useful non-invasive methods to obtain medical images for the diagnosis of respiratory diseases in sheep. The use of ultrasound and thermographic cameras must be enhanced at farm level with the objective of assisting in the diagnosis of major respiratory diseases present in sheep farms. X-ray and, particularly, computed tomography are very interesting tools to facilitate the understanding of the main pathological processes in sheep, especially at the respiratory level. This article shows more than 40 images of thermograms, X-ray, ultrasonography and computed tomography of the most significant respiratory diseases in sheep
Effect of obstacle position in the flow of sheep through a narrow door
In a recent work Phys. Rev. E 91, 022808 (2015)PLEEE81539-375510.1103/PhysRevE.91.022808] it was reported that placing an obstacle in front of a gate has a beneficial effect in the flow of sheep through it. Here, we extend such results by implementing three different obstacle positions. We have observed that the flow is improved in two cases, while it worsens in the other one; the last instance happens when the obstacle is too close to the door. In this situation, the outcomes suggest that clogging develops between the doorjamb and the obstacle, contrary to the cases when the obstacle is farther, in which case clogging always occurs at the very door. The effectiveness of the obstacle (a strategy put forward to alleviate clogging in emergency exits) is therefore quite sensitive to its location. In addition, the study of the temporal evolution of the flow rate as the test develops makes evident a steady behavior during the entire duration of the entrance. This result is at odds with recent findings in human evacuation tests where the flow rate varies over time, therefore challenging the fairness of straightforward comparisons between pedestrian behavior and animal experimental observations
Natural water purification system for local community
A simple household level natural water purification system to purify water to meat small family requirement. It disused with
six important components including Storage, Sedimentation, Biological treatment, and Filtering, Disinfection and Drinking
water storage. During the treatment process Electrical conductivity and Total Dissolved Solids values is not changed but pH
is slightly increased in the bio treatment compartment due to excretion of ammonia form by the fish. A Significant change
of Coli form bacterial count between UV treatment together with sand and Charcoal filter with comparing drinking water
tank It is 90.95% reduction comparing with raw water E coli count is completely removed from this treatment process
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