923 research outputs found

    A space-time neural network

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    Introduced here is a novel technique which adds the dimension of time to the well known back propagation neural network algorithm. Cited here are several reasons why the inclusion of automated spatial and temporal associations are crucial to effective systems modeling. An overview of other works which also model spatiotemporal dynamics is furnished. A detailed description is given of the processes necessary to implement the space-time network algorithm. Several demonstrations that illustrate the capabilities and performance of this new architecture are given

    Neural network for processing both spatial and temporal data with time based back-propagation

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    Neural networks are computing systems modeled after the paradigm of the biological brain. For years, researchers using various forms of neural networks have attempted to model the brain's information processing and decision-making capabilities. Neural network algorithms have impressively demonstrated the capability of modeling spatial information. On the other hand, the application of parallel distributed models to the processing of temporal data has been severely restricted. The invention introduces a novel technique which adds the dimension of time to the well known back-propagation neural network algorithm. In the space-time neural network disclosed herein, the synaptic weights between two artificial neurons (processing elements) are replaced with an adaptable-adjustable filter. Instead of a single synaptic weight, the invention provides a plurality of weights representing not only association, but also temporal dependencies. In this case, the synaptic weights are the coefficients to the adaptable digital filters. Novelty is believed to lie in the disclosure of a processing element and a network of the processing elements which are capable of processing temporal as well as spacial data

    Women in the area of health and science on the border of Mexico between Tamaulipas and Texas

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    Background: The border region between Mexico and Texas configures the space of binational, industrial, commercial and mercantile development, with great business openness on both sides of the border, where the cultural environment is marked by the altered way in which people develop on the border, where the man mostly exercises professional profiles related in the manufacturing maquiladoras area, industrial park, etc. while women are configured as professionals mostly in the area of health services, education and others, but within this space women make their way to science within the development of scientific research, without being identified for the sake of the border, which are usually culturally not associated with the imaginary of the border. Knowing the incursion into this geographical region on both sides of the border, can strengthen and promote the development of women in science and scientific developments, but on addressing the gender gaps in this sector that can also be addressed binationally. Case presentation: One of the main reasons why we want to participate, is due to the need to expose the professional practice of women in the area of health who live in the region of the border border formed between Reynosa, Tamaulipas and the Texas Valley towards Science. With the aim of transmitting the way in which the female gender stands out in the areas of scientific research within the national system of researchers and the gaps of opportunity for early training towards science in the border of Tamaulipas. We consider important the dissemination of information within the event, given that the research and development tasks in science in the border area is developed by women breaking professional stereotypes, but also promoting the path to training in science in early training. Conclusions: Women currently form part of 30% of the total number of researchers in the world, Mexico the participation of women in science is 37%, in the national system of researchers in Mexico there are 33, 166 women in the various areas of knowledge, distinguishes the percentage of women in activities dedicated to health in (medicine) , public health, ext.) In the mexican Republic and even more in the border territoriality in Tamaulipas, it will allow to know and distinguish the gender gaps for the strengthening of the border entity

    Chronic Stress and Ovarian Function in Female Childhood Cancer Survivors

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    Objectives: To explore the relationships among perceived stress, biomarkers of hypothalamic–pituitary–adrenal (HPA) activity, gonadotropin levels, and anti-Müllerian hormone (AMH) in female childhood cancer survivors (CCSs). Sample & Setting: 24 female CCSs from the Royal Hospital for Sick Children in Edinburgh, Scotland, were included in the study. Methods & Variables: Perceived stress was measured using the Perceived Stress Scale. HPA activity was measured using salivary cortisol and hair cortisol. Ovarian function was measured using serum gonadotropin levels and serum AMH levels. Latent growth curve modeling was used to determine diurnal cortisol slope and intercept. Bayesian structural equation modeling was used to explore the relationship among perceived stress, biomarkers of HPA activity, and ovarian function. Results: The authors found an inverse association between perceived stress and ovarian function and a positive association between biomarkers of HPA activity and ovarian function. Implications for Nursing: Further research is needed to understand factors contributing to risk for post-treatment reproductive dysfunction in female CCSs

    Alimentación de modelos cuantitativos con información subjetiva: aplicación Delphi en la elaboración de un modelo de imputación del gasto turístico individual en Catalunya

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    El presente artículo presenta un estudio realizado para el Institut d'Estadística de Catalunya, donde se ha aplicado una técnica que trabaja con información subjetiva (el Método Delphi) para obtener unos datos que puedan ser empleados en la alimentación parcial de un modelo matemático, que se nutre principalmente de datos estadísticos (objetivos), con el fin de incrementar la utilidad global del modelo. El artículo justifica la utilización en determinadas circunstancias de la información subjetiva, describe el método Delphi y plantea una serie de proposiciones referentes a la utilidad, empleo y mejora de esta técnica que se ven refrendadas en el caso expuesto

    An optimized full-configuration-interaction nuclear orbital approach to a “hard-core” interaction problem: Application to (3He)N–Cl2(B) clusters (N<4)

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    13 pages, 8 figures, 3 tables, 3 appendix.An efficient full-configuration-interaction nuclear orbital treatment has been recently developed as a benchmark quantum-chemistry-like method to calculate ground and excited “solvent” energies and wave functions in small doped AEest clusters (N<4) [M. P. de Lara-Castells, G. Delgado-Barrio, P. Villarreal, and A. O. Mitrushchenkov, J. Chem. Phys. 125, 221101 (2006)]. Additional methodological and computational details of the implementation, which uses an iterative Jacobi–Davidson diagonalization algorithm to properly address the inherent “hard-core” He–He interaction problem, are described here. The convergence of total energies, average pair He–He interaction energies, and relevant one- and two-body properties upon increasing the angular part of the one-particle basis set (expanded in spherical harmonics) has been analyzed, considering Cl2 as the dopant and a semiempirical model (T-shaped) He–Cl2(B) potential. Converged results are used to analyze global energetic and structural aspects as well as the configuration makeup of the wave functions, associated with the ground and low-lying “solvent” excited states. Our study reveals that besides the fermionic nature of 3He atoms, key roles in determining total binding energies and wave-function structures are played by the strong repulsive core of the He–He potential as well as its very weak attractive region, the most stable arrangement somehow departing from the one of N He atoms equally spaced on equatorial “ring” around the dopant. The present results for N=4 fermions indicates the structural “pairing” of two 3He atoms at opposite sides on a broad “belt” around the dopant, executing a sort of asymmetric umbrella motion. This pairing is a compromise between maximizing the 3He–3He and the He-dopant attractions, and suppressing at the same time the “hard-core” repulsion. Although the He–He attractive interaction is rather weak, its contribution to the total energy is found to scale as a power of three and it thus increasingly affects the pair density distributions as the cluster grows in size.This work has been partially supported by the CSICCAM, CICYT, and MICINN-CSIC Spanish Grants Nos. CCG08-CSIC/ESP-3680, FIS2007-62006, and 2007501004.Peer reviewe

    The spider Losdolobus nelsoni Pompozzi, 2015 - the first report of the family Orsolobidae in Uruguay (Araneae: Synspermiata)

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    The family Orsolobidae Cooke, 1965, is newly recorded for Uruguay, with the first record of Losdolobus nelson Pompozzi, 2015, a recently described species that is endemic to the Buenos Aires Province, Argentina, and herein recorded in the Rocha and Montevideo departments. The biogeographic implications of this record are commented on and some data on the phenology of the species are presented

    Effects of Scarification, Phytohormones, Soil Type, and Warming on the Germination and/or Seedling Performance of Three Tamaulipan Thornscrub Forest Species

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    The Tamaulipan thornforests of south Texas and northeast Mexico are an ecologically and economically important conservation hotspot. Thornforest restoration is limited by native tree and shrub seedling availability for planting. Seedling shortages arise from low seed availability and knowledge gaps regarding best practices for germinating and growing the 70+ thornforest species desired for restoration plantings. To fill key knowledge gaps, we investigated three ecologically important thornforest species with low or highly variable germination or seedling survival rates: Ebenopsis ebano, Cordia boissieri, and Zanthoxylum fagara. For each, we quantified the effects of different dosages of chemical seed treatments used to promote germination (sulfuric acid, SA; gibberellic acid, GA; indole-3-butyric acid, IBA) on germination likelihood and timing. We also quantified the effects that these chemical seed treatments, soil media mixture type, and soil warming had on seedling survival, growth, and root morphology. Ebenopsis germination peaked (\u3e90%) with 40–60 min SA treatment. Cordia germination peaked (40%) with 100 mg/L GA treatment. Zanthoxylum germination was negligible across all treatments. Seed molding was rare but stirring during SA treatment reduced Ebenopsis molding by 4%. Ebenopsis seedling survival, height, leaf count, and root morphology were minimally affected by seed treatments, generally reduced by warming, and influenced by soil mix, which also mediated responses to warming. These results suggest improvements to existing practices that could increase Ebenopsis germination by 10–20% and potentially double Cordia germination
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