Herramientas de asistencia a la toma de decisiones agronómicas

Las condiciones actuales de producción se basan en la utilización de insumos que tienen consecuencias en el ambiente, y estas se deben tener en cuenta para definir manejos adecuados a largo plazo. El modelado matemático junto con el manejo integrado de malezas ha demostrado ser una herramienta apropiada.Área: Ciencias Agrícolas, Producción y Salud Animal

Planeamiento óptimo del manejo integrado de malezas

En el presente trabajo se propone optimizar un modelo matemático de simulación multianual de escenarios de Manejo Integrado de Malezas (MIM), el cual representa la interacción de la maleza Avena fatua L. en competencia con trigo y cebada, un sistema productivo típico del sudoeste bonaerense. Con este objetivo se desarrolló una herramienta propia basada en el optimizador estocástico por enjambre de partículas (PSO), al cual se le agregaron técnicas para el manejo de restricciones, variables binarias y múltiples objetivos. El estudio propuesto tiene en cuenta tanto el impacto ambiental como el beneficio económico y permite estimar anualmente: (i) el tipo de cultivo a sembrar; (ii) su densidad de siembra; (iii) el tipo de cultivar; (iv) la fecha de siembra; (v) el método de control de la maleza y la (vi) fecha de aplicación del control.Sociedad Argentina de Informática e Investigación Operativ

Sistema web para asistencia en el manejo integrado de malezas: temperatura y humedad de suelos

Un insumo imprescindible para lograr un buen manejo integrado de las malezas es una herramienta que permita estimar de manera precisa su emergencia a campo, es decir, anticipar los flujos de germinación en función de las condiciones meteorológicas de la zona. Con este objetivo se han desarrollado una gran variedad de modelos matemáticos que permiten estimar la emergencia de diferentes malezas basados en datos meteorológicos, en particular, temperatura y precipitación diarios. Entre estos modelos tienen una gran popularidad los de tipo logísticos (sigmoidales, weibull), que utilizan como variable descriptiva algún índice hidrotermal acumulado. Estos índices integran de manera sencilla e intuitiva el calor y la humedad necesarias para la salida de la dormición, la germinación y la emergencia de las malezas. Estos índices se construyen habitualmente con información de la temperatura y humedad del suelo a una dada profundidad en la que se estima se encuentra la semilla. El cálculo de estas variables se realiza mediante balances de masa y energía utilizando información meteorológica, principalmente temperaturas y precipitaciones diarias, así como radiación y viento, entre otras.Sociedad Argentina de Informática e Investigación Operativ

Metabolic responses to the acute ingestion of two commercially available carbonated beverages: A pilot study

<p>Abstract</p> <p>Background</p> <p>The purpose of this placebo-controlled, double-blind cross-over study was to compare the effects of two commercially available soft drinks on metabolic rate.</p> <p>Methods</p> <p>After giving informed consent, twenty healthy men and women were randomly assigned to ingest 12 ounces of Celsius™ and, on a separate day, 12 ounces of Diet Coke®. All subjects completed both trials using a randomized, counterbalanced design. Metabolic rate (via indirect calorimetry) and substrate oxidation (via respiratory exchange ratio) were measured at baseline (pre-ingestion) and at the end of each hour for 3 hours post-ingestion.</p> <p>Results</p> <p>Two-way ANOVA revealed a significant interaction (p < 0.001) between trials in metabolic rate. Scheffe post-hoc testing indicated that metabolic rate increased by 13.8% (+ 0.6 L/min, p < 0.001) 1 hr post, 14.4% (+0.63 L/min, p < 0.001) 2 hr post, and 8.5% (+0.37 L/min, p < 0.004) 3 hr post Celsius™ ingestion. In contrast, small (~4–6%) but statistically insignificant increases in metabolic rate were noted following Diet Coke^®ingestion. No differences in respiratory exchange ratio were noted between trials.</p> <p>Conclusion</p> <p>These preliminary findings indicate Celsius™ has thermogenic properties when ingested acutely. The effects of repeated, chronic ingestion of Celsius™ on body composition are unknown at this time.</p

Decision Support Systems for Weed Management

Editors: Guillermo R. Chantre, José L. González-Andújar.Weed management Decision Support Systems (DSS) are increasingly important computer-based tools for modern agriculture. Nowadays, extensive agriculture has become highly dependent on external inputs and both economic costs, as well the negative environmental impact of agricultural activities, demands knowledge-based technology for the optimization and protection of non-renewable resources. In this context, weed management strategies should aim to maximize economic profit by preserving and enhancing agricultural systems. Although previous contributions focusing on weed biology and weed management provide valuable insight on many aspects of weed species ecology and practical guides for weed control, no attempts have been made to highlight the forthcoming importance of DSS in weed management. This book is a first attempt to integrate 'concepts and practice' providing a novel guide to the state-of-art of DSS and the future prospects which hopefully would be of interest to higher-level students, academics and professionals in related areas

Harpgophytum procumbens for osteoarthritis and low back pain: A systematic review

BACKGROUND: The objective of this review is to determine the effectiveness of Harpagophytum procumbens preparations in the treatment of various forms of musculoskeletal pain. METHODS: Several databases and other sources were searched to identify randomized controlled trials, quasi-randomized controlled trials, and controlled clinical trials testing Harpagophytum preparations in adults suffering from pain due to osteoarthritis or low back pain. RESULTS: Given the clinical heterogeneity and insufficient data for statistical pooling, trials were described in a narrative way, taking into consideration methodological quality scores. Twelve trials were included with six investigating osteoarthritis (two were identical trials), four low back pain, and three mixed-pain conditions. CONCLUSIONS: There is limited evidence for an ethanolic Harpagophytum extract containing less than <30 mg harpagoside per day in the treatment of knee and hip osteoarthritis. There is moderate evidence of effectiveness for (1) the use of a Harpagophytum powder at 60 mg harpagoside in the treatment of osteoarthritis of the spine, hip and knee; (2) the use of an aqueous Harpagophytum extract at a daily dose of 100 mg harpagoside in the treatment of acute exacerbations of chronic non-specific low back pain; and (3) the use of an aqueous extract of Harpagophytum procumbens at 60 mg harpagoside being non-inferior to 12.5 mg rofecoxib per day for chronic non-specific low-back pain (NSLBP) in the short term. Strong evidence exists for the use of an aqueous Harpagophytum extract at a daily dose equivalent of 50 mg harpagoside in the treatment of acute exacerbations of chronic NSLBP

Intersection of inflammation and herbal medicine in the treatment of osteoarthritis

Herbal remedies and dietary supplements have become an important area of research and clinical practice in orthopaedics and rheumatology. Understanding the risks and benefits of using herbal medicines in the treatment of arthritis, rheumatic diseases, and musculoskeletal complaints is a key priority of physicians and their patients. This review discusses the latest advances in the use of herbal medicines for treating osteoarthritis (OA) by focusing on the most significant trends and developments. This paper sets the scene by providing a brief introduction to ethnopharmacology, Ayurvedic medicine, and nutrigenomics before discussing the scientific and mechanistic rationale for targeting inflammatory signalling pathways in OA by use of herbal medicines. Special attention is drawn to the conceptual and practical difficulties associated with translating data from in-vitro experiments to in-vivo studies. Issues relating to the low bioavailability of active ingredients in herbal medicines are discussed, as also is the need for large-scale, randomized clinical trial