Una generalización de la potenciación reticular

En este artículo, utilizando una técnica ideada por Thayse, se introduce una generalización del concepto de potenciación reticular y como subproducto se ofrece una presentación más uniforme de aspectos de la estructura reticular de las funciones discretas, incluyendo algunos resultados adicionales

Designing Pre-test Questions as Phone Notifications: Studying the Effects of a Mobile Learning Intervention

Mobile devices are increasingly becoming more pervasive and emerging as part of our daily life, particularly with university students. From these devices developed in tandem with face-to-face class interaction it has opened new possibilities for ubiquitous learning. We present out work on designing a smart-phone Mobile Learning application that streamlines pre-test questions into a “set it then forget it” input system where students can answer quiz items as slide-down notifications within the day prior to a scheduled lecture. Teachers using the application are afforded a web application to create pre-tests in advance and review class scores. The study was conducted to first-year Computer Science and Information Technology students of a university in the Philippines. Data collection techniques used in the study used experience questionnaires, usability tests, interviews, and tests of student learning outcomes. SUS testing showed consistent satisfactory scores across three iterations. Results from the Learning Experience questionnaire maps to the general answers from the focused group discussion presenting indicative of a positive learning experience. Evaluation of the pre and post test scores signified that using the mobile application can be an effective substitute to class administered tests

Mejora de la productividad del almac?n en una empresa comercializadora mediante la implementaci?n de la gesti?n de inventarios

El presente estudio tiene como objetivo principal determinar la influencia de la Gesti?n de Inventarios en la mejora de la productividad del almac?n de la empresa comercializadora WANCORE S.A. y objetivos espec?ficos; establecer la contribuci?n de la rotaci?n de inventarios y la valorizaci?n de los inventarios en la entrega de pedidos sin errores. As? mismo, el ?ltimo objetivo espec?fico buscar determinar la influencia de la exactitud de inventarios sobre el cumplimiento a tiempo de los despachos. La investigaci?n es de tipo aplicada correlacional, con un dise?o cuasi-experimental. La aplicaci?n de las herramientas de la Gesti?n de Inventarios logr? solucionar el inconveniente de la baja productividad; porque la empresa empez? a reportar altos ?ndices de devoluci?n de pedidos, p?rdidas de mercader?a, despachos atendidos fuera de tiempo, errores en la preparaci?n de pedidos, entre otros motivos. Por ello, con la intervenci?n de la gesti?n de inventarios, la productividad del almac?n logr? mejorar; ya que se obtuvo un incremento del 20%. Finalmente, la conclusi?n principal es la determinaci?n de la contribuci?n total del sistema en la mejora de la productividad

Adaptation of the Clinical Dementia Rating Scale for adults with Down syndrome

BACKGROUND: Adults with Down syndrome (DS) are at increased risk for Alzheimer disease dementia, and there is a pressing need for the development of assessment instruments that differentiate chronic cognitive impairment, acute neuropsychiatric symptomatology, and dementia in this population of patients. METHODS: We adapted a widely used instrument, the Clinical Dementia Rating (CDR) Scale, which is a component of the Uniform Data Set used by all federally funded Alzheimer Disease Centers for use in adults with DS, and tested the instrument among 34 DS patients recruited from the community. The participants were assessed using two versions of the modified CDR-a caregiver questionnaire and an in-person interview involving both the caregiver and the DS adult. Assessment also included the Dementia Scale for Down Syndrome (DSDS) and the Raven\u27s Progressive Matrices to estimate IQ. RESULTS: Both modified questionnaire and interview instruments captured a range of cognitive impairments, a majority of which were found to be chronic when accounting for premorbid function. Two individuals in the sample were strongly suspected to have early dementia, both of whom had elevated scores on the modified CDR instruments. Among individuals rated as having no dementia based on the DSDS, about half showed subthreshold impairments on the modified CDR instruments; there was substantial agreement between caregiver questionnaire screening and in-person interview of caregivers and DS adults. CONCLUSIONS: The modified questionnaire and interview instruments capture a range of impairment in DS adults, including subthreshold symptomatology, and the instruments provide complementary information relevant to the ascertainment of dementia in DS. Decline was seen across all cognitive domains and was generally positively related to age and negatively related to IQ. Most importantly, adjusting instrument scores for chronic, premorbid impairment drastically shifted the distribution toward lower (no impairment) scores

Eutrophication and macroalgal blooms in temperate and tropical coastal waters: Nutrient enrichment experiments with Ulva spp.

Receiving coastal waters and estuaries are among the most nutrient-enriched environments on earth, and one of the symptoms of the resulting eutrophication is the proliferation of opportunistic, fast-growing marine seaweeds. Here, we used a widespread macroalga often involved in blooms, Ulva spp., to investigate how supply of nitrogen (N) and phosphorus (P), the two main potential growth-limiting nutrients, influence macroalgal growth in temperate and tropical coastal waters ranging from low- to high-nutrient supplies. We carried out N and P enrichment field experiments on Ulva spp. in seven coastal systems, with one of these systems represented by three different subestuaries, for a total of nine sites. We showed that rate of growth of Ulva spp. was directly correlated to annual dissolved inorganic nitrogen (DIN) concentrations, where growth increased with increasing DIN concentration. Internal N pools of macroalgal fronds were also linked to increased DIN supply, and algal growth rates were tightly coupled to these internal N pools. The increases in DIN appeared to be related to greater inputs of wastewater to these coastal waters as indicated by high δ15N signatures of the algae as DIN increased. N and P enrichment experiments showed that rate of macroalgal growth was controlled by supply of DIN where ambient DIN concentrations were low, and by P where DIN concentrations were higher, regardless of latitude or geographic setting. These results suggest that understanding the basis for macroalgal blooms, and management of these harmful phenomena, will require information as to nutrient sources, and actions to reduce supply of N and P in coastal waters concerned.Fil: Teichberg, Mirta. Leibniz Center For Tropical Marine Research; AlemaniaFil: Fox, Sophia E.. Marine Biological Laboratory; Estados UnidosFil: Olsen, Ylva S.. Bangor University; Reino UnidoFil: Valiela, Ivan. Marine Biological Laboratory; Estados UnidosFil: Martinetto, Paulina Maria del Rosario. Universidad Nacional de Mar del Plata; ArgentinaFil: Iribarne, Oscar Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Muto, Elizabeti Yuriko. Universidade de Sao Paulo; BrasilFil: Petti, Monica A.V.. Universidade de Sao Paulo; BrasilFil: Corbisier, Thaïs N.. Universidade de Sao Paulo; BrasilFil: Soto-Jiménez, Martín. Universidad Nacional Autónoma de México; MéxicoFil: Páez-Osuna, Federico. Universidad Nacional Autónoma de México; MéxicoFil: Castro, Paula. University Of Coimbra; BrasilFil: Freitas, Helena. University Of Coimbra; BrasilFil: Zitelli, Andreina. Università Iuav Di Venezia; ItaliaFil: Cardinaletti, Massimo. Gruppo Veritas; ItaliaFil: Tagliapietra, Davide. Consiglio Nazionale delle Ricerche; Itali

Pelletized Forage-Based Rations as Alternative Feeds for Improving Goat Productivity

Goat farming is very popular in the Philippines as it is considered by many to be a viable rural enterprise. Despite this, the goat industry is faced with many challenges, including problems relating to high pre-weaning mortality, poor nutrition and lack of strategic approaches to accelerate genetic improvement. The long term rate of increase of goat numbers is only 0.97% per annum, due to high offtake rates and low productivity. Thus, the Philippine goat population is only expected to reach 4.27million by 2020 (compared with the target of 6.2 million), given the 3.88million population in 2010 (Alo 2012). Interventions are needed to accelerate growth of the goat population. Goats are typically fed on locally available resources which are characterised by low quality and highly variable availability. These characteristics can be overcome through processing techniques such as sun drying and pelleting to ensure year round feed supply. Pelleting offers particular advantages. Feeding animals with pellets provides better feed efficiency, greater starch digestibility, less feed waste, non-selective feeding, better handling and storage, and increased income due to more efficient feeding and higher productivity. While pellets are available for swine, poultry and buffalo in the Philippine market, pellets for goats are not currently available. The aim of this study was to develop pelletized forage-based rations for goats and evaluate them for their technical and financial viability

Efecto de jugo y pulpa de pomelo (Citrus grandis) del noreste argentino sobre parámetros fisicoquímicos y propiedades de barrera de películas biodegradables de almidón de mandioca

El envase de un alimento debe mantener la calidad organoléptica y microbiológica del producto, además de evitar la posible pérdida de compuestos bioactivos. A través de la formulación de la película que constituye el envase se puede controlar las propiedades de barrera, las cuales son afectadas, entre otros factores, por el espesor del film, el tipo de plastificante y otros componentes adicionados. El objetivo fue incorporar jugo y pulpa de pomelo a matrices de almidón de mandioca, con glicerol y miel como plastificantes y determinar sus parámetros fisicoquímicos y propiedades de barrera.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Propiedades físicas, reológicas y mecánicas de películas biodegradables de almidón de mandioca con jugo de pomelo (Citrus grandis) del noreste argentino

El pomelo contiene compuestos bioactivos (minerales, fibra, carotenoides, fenoles, vitamina C) y además valores altos de acidez. Tanto el pomelo como el almidón de mandioca son recursos naturales del noreste argentino que pueden ser aprovechados para generar envases biodegradables para alimentos. El objetivo fue formular matrices aptas para la formación de películas a base de almidón de mandioca y glicerol y miel como plastificantes con diferentes proporciones de jugo de pomelo y determinar sus propiedades físicas y tecnológicas.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Parámetros fisicoquímicos de calidad y textura de frutos del noreste argentino sometidos a almacenamiento congelado

El objetivo fue seleccionar frutos (mamón y pomelo) en diferentes estados de madurez, congelarlos, determinar sus parámetros fisicoquímicos y de textura y su contenido de polifenoles. Los frutos fueron recolectados en Presidencia Roque Sáenz Peña, Chaco, seleccionando dos lotes en estado verde-maduro y maduro. Los frutos se almacenaron 30 días a -20°C y se realizaron las determinaciones en los productos frescos y congelados. Se midió altura, diámetro, rendimiento de pulpa, pH, acidez titulable, grados Brix y grado de madurez. El color superficial se determinó con colorímetro de superficie y el contenido de polifenoles por el método de Folin-Ciocalteu. Se realizaron ensayos de punción en texturómetro. El almacenamiento congelado disminuyó los parámetros de color a*, b* y L* en mamones y modificó en menor medida los de pomelos. La fuerza máxima de punción en los pomelos no varió luego de la congelación, en cambio aumentó en los mamones maduros y disminuyó en los verdes. El contenido de polifenoles de ambas frutas en los dos estados de madurez fue mayor luego de la congelación excepto en mamones verdes. Ambas frutas preservadas pueden considerarse para elaborar alimentos de alto valor nutricional ya que la congelación fue apropiada para mantener los parámetros de calidad.Centro de Investigación y Desarrollo en Criotecnología de Alimento