Topological Test Spaces

A test space is the set of outcome-sets associated with a collection of experiments. This notion provides a simple mathematical framework for the study of probabilistic theories -- notably, quantum mechanics -- in which one is faced with incommensurable random quantities. In the case of quantum mechanics, the relevant test space, the set of orthonormal bases of a Hilbert space, carries significant topological structure. This paper inaugurates a general study of topological test spaces. Among other things, we show that any topological test space with a compact space of outcomes is of finite rank. We also generalize results of Meyer and Clifton-Kent by showing that, under very weak assumptions, any second-countable topological test space contains a dense semi-classical test space.Comment: 12 pp., LaTeX 2e. To appear in Int. J. Theor. Phy

Consumidores de frutos de Persea lingue (Lauraceae) en el sur de Chile y su efecto en la germinación de semillas

Frugivory is a common interaction mechanism between plants and animals in the temperate rainforest of southernSouth America. In this study, we examined primary dispersal and predation stages of Persea lingue (Ruiz et Pav.) Nees(Lauraceae), an endemic large-seeded tree of these forests. The main goal was to determine the identity of vertebrate seeddispersers of P. lingue, to distinguish legitimate seed dispersers, pulp consumers and seed predators, and their influenceon seed germination. In order to know which birds and small mammals were feeding P. lingue seeds, we observed 20P. lingue canopies, and live traps baited with P. lingue seeds were installed in fragment forests in south-central Chile.To determine whether birds could be legitimate dispersers of P. lingue, we collected regurgitated and fecal samples. Weexamined whether rodents removed the fruit pulp, the seeds, or the whole fruit. Additionally, we studied if seeds placedon the forest floor were removed by rodents. In a final experiment we conducted germination trials to establish whetherpulp removal (by birds, rodents, or artificially-removed) influenced germination rates. We found six bird species feedingon P. lingue seeds. None of them defecated intact seeds, but, Turdus falcklandii Quoy & Gaimard (Turdinae) and Xolmispyrope (Kittlitz) (Tyrannidae) regurgitated intact seeds. We captured five species of rodents in Sherman traps. Four of themleft intact seeds. We did not find any effect of the seed handling types (pulp consumption vs. seed regurgitation) in seedgermination rates. However, pulp removal was an important factor for germination success. We conclude that T. falcklandiiand X. pyrope are legitimate seed dispersers of P. lingue, since they swallow the whole fruit and regurgitate the intactseed. Abrothrix olivaceus (Waterhouse) (Cricetidae) and probably Oligoryzomys longicaudatus (Bennett) (Cricetidae) arepotential secondary dispersers of P. lingue seeds, as they prefer to eat the fruit pulp rather than the seeds.La dispersión de semillas por endozoocoría es uno de los principales mecanismos de interacción mutualista entre plantas yanimales en el bosque templado de Sudamérica. En este estudio indagamos acerca de los mecanismos de dispersión primariay estadios de depredación de semillas de Persea lingue (Ruiz et Pav.) Nees (Lauraceae), árbol endémico de estos bosques.El objetivo principal fue determinar la identidad de los vertebrados dispersores de semillas de P. lingue, distinguiendodispersores legítimos, de consumidores de pulpa y predadores de semillas, y determinar su efecto en la germinación. Serealizaron observaciones focales de la copa de adultos de P. lingue; además, se instalaron trampas Sherman cebadas confrutos de P. lingue en fragmentos de bosque en el valle central del centro-sur de Chile. Se colectaron muestras de fecasy semillas regurgitadas, se determinó cuáles especies de roedores consumieron la pulpa, las semillas o los frutos enterosen las trampas. Se examinó si hubo remoción de frutos y semillas desde el suelo. Se realizó un ensayo de germinaciónpara determinar si la forma de la remoción de la pulpa afecta las tasas de germinación. Registramos seis especies de avesconsumiendo frutos, ninguna defecó semillas, Turdus falcklandii Quoy & Gaimard (Turdinae) y Xolmis pyrope (Kittlitz)(Tyrannidae) regurgitaron semillas intactas. Capturamos cinco especies de roedores en las trampas, cuatro dejaron semillasintactas. No encontramos efecto del tipo de manipulación de las semillas en su germinación. La remoción de la pulpa fuedeterminante para el éxito de germinación. Concluimos que T. falcklandii y X. pyrope son dispersores legítimos de semillasde P. lingue. Abrothrix olivaceus (Waterhouse) (Cricetidae) y probablemente Oligoryzomys longicaudatus (Bennett)(Cricetidae) son potenciales dispersores secundarios, dada su marcada preferencia por la pulpa sobre las semillas

Planificación de red de acceso radio UMTS/HSDPA

Los sistemas de segunda generación presentan limitaciones en ancho de banda yservicios que pueden soportar. En cambio, los sistemas de tercera generación tienen lacapacidad de ofrecer elevadas velocidades de transferencia, calidad de servicio y nuevasaplicaciones. El objetivo del presente trabajo es diseñar una red de telecomunicacionesmóvil de tercera generación UMTS/HSDPA y proponer un escenario de incursión realde COMTECO en el mercado de la telefonía móvil como un cuarto operador. Lametodología empleada en el presente proyecto tiene como base un estudiocuantitativo, analítico, teórico y descriptivo. Se inicia el proceso de pre planificaciónmediante la definición de servicios y la estimación de una proyección de demanda en eldepartamento. Posteriormente, se pasa a la fase de planificación, en la que, medianteun estudio del balance de potencias, se llega a un equilibrio en cuanto a cobertura ycapacidad, y se logra determinar la cantidad de nodos necesarios y su configuración.Adoptando la metodología de planificación propuesta se consigue realizar laplanificación de acceso radio acorde a las necesidades y facilidades que tieneCOMTECO, asegurando la cobertura deseada en las zonas de interés y procurandouna buena calidad de los servicios

History, synthesis, properties, applications and regulatory issues of prebiotic oligosaccharides

In this chapter, the health promoting effects of carbohydrate prebiotics are addressed. A brief description of their synthesis, thermo-physical properties, mechanisms of action, technological applications and current regulatory issues are presented

Exergy cost assessment of solar trigeneration plant based on a concentrated solar power plant as the prime mover

An exergy cost assessment of solar trigeneration plant to generate electricity, fresh-water, and heat is carried out in order to study the process of exergy cost formation, to determine the key components that contribute to the cost of each product, and to establish the best configuration in term of unit exergy cost. The solar trigeneration plants evaluated consist of a concentrated solar power (CSP), a multi-effect distillation plant, and a process heat module, in which the CSP plant is the prime mover. The methodology includes modeling and evaluating the performance of standalone and trigeneration plants using the symbolic exergoeconomic methodology. Results show that the best configuration, in terms of exergy cost, is when the multi-effect distillation plant replaces the power cycle condenser. Regarding the costs formation, the key components which could be improved in their design are: solar collectors, evaporator, re-heater, dissipative systems, and productive subsystems

Parametrical model of cardiac cell electrical activity estimated from standard electrocardiogram recordings

El presente trabajo tiene como objetivo principal relacionar la actividad eléctrica cardiaca celular con la actividad eléctrica cardiaca medida en una sola derivación del electrocardiograma (ECG), mediante un modelo paramétrico de potencial de acción (PA) celular, lo cual se llevó a cabo relacionando dinámicas conocidas, matemáticamente modelables, que existen a nivel de una célula cardiaca, a dinámicas que pueden ser encontradas en un registro ECG estándar. La principal dinámica celular a relacionar con el ECG es la conocida como curva de restitución celular en tres dimensiones, la cual relaciona la duración del potencial de acción celular (APD) con el intervalo diastólico que lo precede y con el mismo APD pero del ciclo cardiaco precedente. Curvas de restitución similares se encontraron en señales ECG registradas durante el test isométrico handgrip, relacionando el intervalo QT con el intervalo TQ que lo precede y con el intervalo QT del ciclo cardiaco precedente. Siguiendo esta similitud, un modelo paramétrico de curva de restitución, extraído de un modelo de PA a tres corrientes iónicas, es ajustado a la curva de restitución del ECG con el fin de estimar los parámetros del modelo de PA. Este modelo es finalmente simulado estimulándolo con un tren de impulsos de frecuencia igual a la frecuencia cardiaca del sujeto experimentado. Los resultados muestran que la curva de restitución obtenida experimentalmente a partir del ECG es similar a la obtenida a partir de la simulación del modelo de PA. Más aún, el APD simulado del modelo sigue de forma satisfactoria la variación en el tiempo del intervalo QT del sujeto experimentado. Esto abre nuevas perspectivas en el análisis de la actividad celular a partir de registros ECG estándar.The main purpose of this paper is to relate cellular cardiac electrical activity with the cardiac electrical activity measured in only one electrocardiogram (ECG) lead, through a cellular action potential (AP) parametrical model. This is performed by relating known dynamics, which can be mathematically modeled, existing at a cardiac cell level, to dynamics which can be obtained from a standard ECG recording. The main cellular dynamic used for relating with the ECG is the one known as three dimensional cellular restitution curve, which relates the action potential duration (APD) with its preceding diastolic interval and with the APD of the preceding cardiac cycle. Similar restitution curves were found in ECG signals recorded under the isometric handgrip test by relating the QT interval with its preceding TQ interval and with the QT interval of the preceding cardiac cycle. Following this similarity, a parametrical restitution curve, derived from a three ionic current cellular AP model was fitted to the ECG restitution relation for AP model parameter estimation. This model is finally simulated by stimulating it with an impulse train of frequency similar to the heart rate of the tested subject. The results show that the restitution curve experimentally obtained from the ECG is similar to the one obtained from de AP model simulation. Moreover the simulated APD follows satisfactorily the QT interval time variation of the tested subject. This opens new perspectives for the analysis of cellular cardiac electrical activity from standard ECG recordings

Artificial intelligence surgery: how do we get to autonomous actions in surgery?

Most surgeons are skeptical as to the feasibility of autonomous actions in surgery. Interestingly, many examples of autonomous actions already exist and have been around for years. Since the beginning of this millennium, the field of artificial intelligence (AI) has grown exponentially with the development of machine learning (ML), deep learning (DL), computer vision (CV) and natural language processing (NLP). All of these facets of AI will be fundamental to the development of more autonomous actions in surgery, unfortunately, only a limited number of surgeons have or seek expertise in this rapidly evolving field. As opposed to AI in medicine, AI surgery (AIS) involves autonomous movements. Fortuitously, as the field of robotics in surgery has improved, more surgeons are becoming interested in technology and the potential of autonomous actions in procedures such as interventional radiology, endoscopy and surgery. The lack of haptics, or the sensation of touch, has hindered the wider adoption of robotics by many surgeons; however, now that the true potential of robotics can be comprehended, the embracing of AI by the surgical community is more important than ever before. Although current complete surgical systems are mainly only examples of tele-manipulation, for surgeons to get to more autonomously functioning robots, haptics is perhaps not the most important aspect. If the goal is for robots to ultimately become more and more independent, perhaps research should not focus on the concept of haptics as it is perceived by humans, and the focus should be on haptics as it is perceived by robots/computers. This article will discuss aspects of ML, DL, CV and NLP as they pertain to the modern practice of surgery, with a focus on current AI issues and advances that will enable us to get to more autonomous actions in surgery. Ultimately, there may be a paradigm shift that needs to occur in the surgical community as more surgeons with expertise in AI may be needed to fully unlock the potential of AIS in a safe, efficacious and timely manner

Tratamiento estadístico de datos meteorológicos en Villa Unión, Dpto. Cnel. F. Varela La Rioja, periodo junio 2010-julio 2011.

This study assessed the climatic data for meteorological stations and rainfall of the study area were obtained monthly mean precipitation and annual average methods: arithmetic and Thiessen polygons by drawing isohyets, average temperatures, maximum and monthly minimum, values of humidity, wind speed and atmospheric pressure, as well as agro-meteorological data, for the period July 2010 - June 2011.Astation in El Molle and one in Los Palacios, and two digital gauges for the Banda Florida district and Guillermo Paez.En este trabajo se evaluaron los datos climáticos correspondientes a las estaciones meteorológicas y pluviométricas de la zona de estudio y se obtuvieron las precipitaciones medias mensuales y medias anuales por los métodos: aritmético, polígonos de Thiessen y mediante el trazado de isoyetas; temperaturas medias, máximas y mínimas mensuales; valores de humedad; velocidad del viento y presión atmosférica, además de datos agrometeorológicos, correspondientes al periodo julio 2010-junio 2011. Una estación en la localidad de El Molle y otra en la localidad de Los Palacios, y dos pluviómetros digitales correspondientes a la localidad de Banda Florida y el barrio de Guillermo Páez