Permanencia de sellantes en primeros molares permanentes en pacientes de 7 y 8 anos atendidos previamente por el programa GES en el Consultorio Sol de Septiembre de Curico, 2007

74 p.Introducción: Los sellantes fueron introducidos como un eficaz método de prevención de caries de fosas y fisuras según como lo indican numerosos estudios (Simonsen, 2002). Su éxito está dado por la unión micromecánica entre el sellante y el esmalte dentario producto del grabado ácido (Hitt y Feigal, 1992). Las técnicas adhesivas son enormemente sensibles a la técnica, por ende es crítico el momento de la acción clínica que va desde una adecuada profilaxis, hasta una correcta aplicación evitando la contaminación de las zonas selladas. La retención del sellante en la pieza dentaria forma una barrera que impide el proceso carioso de fosas y fisuras. Objetivos: Determinar el grado de retención de los sellantes aplicados en primeros molares permanentes a 1 y 2 años de aplicados en el programa Ges y comparar diferencias de retención entre piezas superiores e inferiores y entre cada molar por separado. Método: De un total de 83 pacientes que cumplían con los criterios de inclusión, 245 primeros molares fueron revisados por el examinador y se determinó el grado de retención según los criterios de Simonsen (1991). Se confeccionó una ficha en la cual se registraron los datos personales de los pacientes, así como también la fecha en la que fueron realizados los sellantes, indagando en la ficha clínica realizada anteriormente en el consultorio. Resultados: El grado de retención de los sellantes fue de 33% Totalmente retenidos, 57% Parcialmente retenidos y 10% Ausentes. Hubo diferencia estadísticamente significativa (p=0,03) para demostrar un mayor grado de retención en molares inferiores (41% Totalmente retenidos, 53% Parcialmente retenidos y 6% Ausentes) que en molares superiores (25% Totalmente retenidos, 61% Parcialmente retenidos y 14% Ausentes). Además hubo mayor porcentaje de pérdida en sellantes aplicados en el año 2006 que en 2005. No existieron diferencias estadísticamente significativas en el grado de retención en molares entre si p>0,05. Conclusiones: El grado de retención que presentaron los sellantes (90%), tanto total como parcial disminuye la probabilidad de generar caries de fosas y fisuras, por lo que podemos hablar de éxito en esta terapia de tipo preventiva, la que junto a: educación, técnicas de higiene, flúor y controles periódicos disminuyen ostensiblemente la incidencia de caries

Listening to mental health crisis needs at scale: using Natural Language Processing to understand and evaluate a mental health crisis text messaging service

The current mental health crisis is a growing public health issue requiring a large-scale response that cannot be met with traditional services alone. Digital support tools are proliferating, yet most are not systematically evaluated, and we know little about their users and their needs. Shout is a free mental health text messaging service run by the charity Mental Health Innovations, which provides support for individuals in the UK experiencing mental or emotional distress and seeking help. Here we study a large data set of anonymised text message conversations and post-conversation surveys compiled through Shout. This data provides an opportunity to hear at scale from those experiencing distress; to better understand mental health needs for people not using traditional mental health services; and to evaluate the impact of a novel form of crisis support. We use natural language processing (NLP) to assess the adherence of volunteers to conversation techniques and formats, and to gain insight into demographic user groups and their behavioural expressions of distress. Our textual analyses achieve accurate classification of conversation stages (weighted accuracy = 88%), behaviours (1-hamming loss = 95%) and texter demographics (weighted accuracy = 96%), exemplifying how the application of NLP to frontline mental health data sets can aid with post-hoc analysis and evaluation of quality of service provision in digital mental health services

Walks on Apollonian networks

We carry out comparative studies of random walks on deterministic Apollonian networks (DANs) and random Apollonian networks (RANs). We perform computer simulations for the mean first passage time, the average return time, the mean-square displacement, and the network coverage for unrestricted random walk. The diffusions both on DANs and RANs are proved to be sublinear. The search efficiency for walks with various strategies and the influence of the topology of underlying networks on the dynamics of walks are discussed. Contrary to one's intuition, it is shown that the self-avoiding random walk, which has been verified as an optimal strategy for searching on scale-free and small-world networks, is not the best strategy for the DAN in the thermodynamic limit.Comment: 5 pages, 4 figure

A new method for analyzing ground-state landscapes: ballistic search

A ``ballistic-search'' algorithm is presented which allows the identification of clusters (or funnels) of ground states in Ising spin glasses even for moderate system sizes. The clusters are defined to be sets of states, which are connected in state-space by chains of zero-energy flips of spins. The technique can also be used to estimate the sizes of such clusters. The performance of the method is tested with respect to different system sizes and choices of parameters. As an application the ground-state funnel structure of two-dimensional +or- J spin glasses of systems up to size L=20 is analyzed by calculating a huge number of ground states per realization. A T=0 entropy per spin of s_0=0.086(4)k_B is obtained.Comment: 10 pages, 11 figures, 35 references, revte

Ordered phase in the two-dimensional randomly coupled ferromagnet

True ground states are evaluated for a 2d Ising model with random near neighbor interactions and ferromagnetic second neighbor interactions (the Randomly Coupled Ferromagnet). The spin glass stiffness exponent is positive when the absolute value of the random interaction is weaker than the ferromagnetic interaction. This result demonstrates that in this parameter domain the spin glass like ordering temperature is non-zero for these systems, in strong contrast to the 2d Edwards-Anderson spin glass.Comment: 7 pages; 9 figures; revtex; new version much extende

Completeness of classical spin models and universal quantum computation

We study mappings between distinct classical spin systems that leave the partition function invariant. As recently shown in [Phys. Rev. Lett. 100, 110501 (2008)], the partition function of the 2D square lattice Ising model in the presence of an inhomogeneous magnetic field, can specialize to the partition function of any Ising system on an arbitrary graph. In this sense the 2D Ising model is said to be "complete". However, in order to obtain the above result, the coupling strengths on the 2D lattice must assume complex values, and thus do not allow for a physical interpretation. Here we show how a complete model with real -and, hence, "physical"- couplings can be obtained if the 3D Ising model is considered. We furthermore show how to map general q-state systems with possibly many-body interactions to the 2D Ising model with complex parameters, and give completeness results for these models with real parameters. We also demonstrate that the computational overhead in these constructions is in all relevant cases polynomial. These results are proved by invoking a recently found cross-connection between statistical mechanics and quantum information theory, where partition functions are expressed as quantum mechanical amplitudes. Within this framework, there exists a natural correspondence between many-body quantum states that allow universal quantum computation via local measurements only, and complete classical spin systems.Comment: 43 pages, 28 figure

Scaling Properties of Random Walks on Small-World Networks

Using both numerical simulations and scaling arguments, we study the behavior of a random walker on a one-dimensional small-world network. For the properties we study, we find that the random walk obeys a characteristic scaling form. These properties include the average number of distinct sites visited by the random walker, the mean-square displacement of the walker, and the distribution of first-return times. The scaling form has three characteristic time regimes. At short times, the walker does not see the small-world shortcuts and effectively probes an ordinary Euclidean network in $d$-dimensions. At intermediate times, the properties of the walker shows scaling behavior characteristic of an infinite small-world network. Finally, at long times, the finite size of the network becomes important, and many of the properties of the walker saturate. We propose general analytical forms for the scaling properties in all three regimes, and show that these analytical forms are consistent with our numerical simulations.Comment: 7 pages, 8 figures, two-column format. Submitted to PR

Bringing Statistical Methodologies for Enterprise Integration of Conversational Agents

Proceedings of: 9th International Conference on Practical Applications of Agents and Multiagent Systems (PAAMS 11). Salamanca, 6-8 April, 2011In this paper we present a methodology to develop commercial conversational agents that avoids the effort of manually defining the dialog strategy for the dialog management module. Our corpus-based methodology is based on selecting the next system answer by means of a classification process in which the complete dialog history is considered. This way, system developers can employ standards like VoiceXML to simply define system prompts and the associated grammars to recognize the users responses to the prompt, and the statistical dialog model automatically selects the next system prompt.We have applied this methodology for the development of an academic conversational agent.Funded by projects CICYT TIN2008-06742-C02-02/TSI, CICYT TEC 2008-06732-C02-02/TEC, CAM CONTEXTS (S2009/TIC-1485), and DPS2008-07029- C02-02.Publicad

Conociendo el ciclo del agua : las aventuras de Tui y Kerekere en los ríos del Chaco

El agua es el recurso más importante para los seres humanos y organismos vivos del planeta. En la naturaleza se la puede encontrar de diversas formas y en distintos lugares. La observamos en las nubes del cielo, en la nieve de las montañas, en el rocío y niebla de la mañana, y recorriendo las vertientes que nacen en nuestros bosques y montañas. Las aventuras de Tui y Kerekere "Conociendo el ciclo del agua" es la primera de cuatro historias educativas desarrolladas por la Fundación Amigos de la Naturaleza en el marco del Proyecto "Balance Hídrico, Calidad Biológica y Gestión del Agua en la parte Sub-andina del Chaco Boliviano" en su componente de Ciencia Participativa, que busca dar a conocer a los niños y jóvenes de un modo sencillo y comprensible a cerca de los componentes de la gestión y cuidado del agua. Este material está dirigido a niños, profesores y pobladores del Chaco, es una guía de aprendizaje y sensibilización hacia los recursos hídricos

El valor del bosque : las aventuras de Tui y Kerekere en los ríos del Chaco

El agua es el recurso más importante para los seres humanos y organismos vivos del planeta. En la naturaleza se la puede encontrar de diversas formas y en distintos lugares. La observamos en las nubes del cielo, en la nieve de las montañas, en el rocío y niebla de la mañana, y recorriendo las vertientes que nacen en nuestros bosques y montañas. Las aventuras de Tui y Kerekere "El valor del bosque" es la segunda de cuatro historias educativas desarrolladas por la Fundación Amigos de la Naturaleza en el marco del Proyecto "Balance Hídrico, Calidad Biológica y Gestión del Agua en la parte Sub-andina del Chaco Boliviano" en su componente de Ciencia Participativa, que busca dar a conocer a los niños y jóvenes de un modo sencillo y comprensible a cerca de los componentes de la gestión y cuidado del agua. Este material está dirigido a niños, profesores y pobladores del Chaco, es una guía de aprendizaje y sensibilización hacia los recursos hídricos