5,191 research outputs found
Conodont biostratigraphy of the Crawford Group, Southern Uplands, Scotland
Extensive new conodont collections from the Crawford Group, the oldest succession in the Southern Uplands of Scotland, support the previously documented biostratigraphical ages for the included formations. The Raven Gill Formation is lower Whitlandian, Arenig (comparable in age to the Dounans Limestone in the Highland Border Complex) and the Kirkton Formation is latest Llandeilian-Aurelucian, Llanvirn to Caradoc in age. It is concluded that there is a significant stratigraphical gap within the Crawford Group. The restricted and probably fault-bounded nature of the Raven Gill outcrops suggests that these may represent olistoliths within a mélange of Llandeilian-Aurelucian age. The chert-bearing succession of the Northern Belt of the Southern Uplands thus represents the juxtaposed sedimentary records of two entirely separate basins – the oldest pre-dates the Grampian assembly of the Laurentian margin, and the younger, the Northern Belt Basin sensu stricto, entirely post-dates this event
White mold
White mold, caused by the fungus Sclerotinia (Whetzelinia) sclerotiorum, is distributed worldwide and has more than 300 hosts. It infects flowers, cotyledons, seeds, leaves, or injured plant tissue. The disease can be controlled by crop rotation, flooding, reduced seeding rates, fewer irrigations, and destruction of bean- cull screenings containing sclerotia. Other control measures include chemical products in the middle of the flowering period, modifying plant architecture, and using resistant var. Many soil microorganisms are associated with sclerotia and may cause them to degrade or fail to germinate. The symptoms and damage caused by the disease are illustrated in color. (CIAT)El moho blanco causado por el hongo Sclerotinia (Whetzelinia) sclerotiorum se halla presente en todo el mundo, con mas de 300 plantas hospedantes del patogeno; infecta las flores, cotiledones, semillas, hojas o tejido lesionado. El control de la enfermedad se puede hacer por rotacion de cultivos, inundacion del terreno, menos riego y destruccion de residuos con esclerocios y utilizacion de menor cantidad de semilla en la siembra. Otras medidas de control incluyen la aplicacion de productos quimicos a mediados de la floracion, la modificacion de la arquitectura de la planta y la utilizacion de var. resistentes. Muchos microorganismos del suelo se asocian con los esclerocios y pueden causar degradacion e impedir que estos germinen. Se ilustran a color los sintomas y danos causados por la enfermedad. (CIAT
El moho blanco
White mold, caused by the fungus Sclerotinia (Whetzelinia) sclerotiorum, is distributed worldwide and has more than 300 hosts. It infects flowers, cotyledons, seeds, leaves or injured plant tissue. The disease can be controlled by crop rotation, flooding, reduced seeding rates, application of chemical products in the middle of the flowering period, modifying plant architecture and the use of resistant var. Many soil microorganisms are associated with sclerotia and may cause them to degrade or fan to germinate. The symptoms and damage caused by the disease are illustrated in color. (CIAT)El moho blanco causado por el hongo Sclerotinia (Whetzelinia) sclerotiorum se halla presente en todo el mundo y mas de 300 plantas son hospedantes del patogeno; infecta las flores, cotiledones, semillas, hojas o tejido herido. El control de la enfermedad se puede hacer por: rotacion de cultivos, inundacion del terreno, utilizacion de menor cantidad de semilla en la siembra, aplicacion de productos quimicos a mediados de la floracion, modificando la arquitectura de la planta y utilizando var resistentes; muchos microorganismos del suelo estan asociados con los esclerosios y pueden causar degradacion e impedir que estos germinen. Se ilustran en color los sintomas y danos causados por la enfermedad. (CIAT
A Strategic Approach to Agricultural Research Program Planning in Sub-Saharan Africa
Recent studies have shown that agricultural research can have high payoffs in Africa, but impact depends on how well technology fits with evolving needs and capacity in the agricultural sector and the rest of the economy. Structural adjustment policies (e.g., market liberalization, currency devaluation) and political change are transforming user demands for new technology and the economic environment in which technology must perform. The challenge is how to design agricultural research as a strategic input to promote broad-based economic growth, structural transformation, and food security in the increasingly market-driven, but fragile, economies of Africa.Food Security, Food Policy, Agricultural Research, Research and Development/Tech Change/Emerging Technologies, Downloads May 2008-July 2009: 44, Q18,
A Strategic Approach to Agricultural Research Program Planning in Sub-Saharan Africa
Research and Development/Tech Change/Emerging Technologies, Downloads May 2008-July 2009: 13,
Engineered Structured Sorbents for the Adsorption of Carbon Dioxide and Water Vapor from Manned Spacecraft Atmospheres: Applications and Modeling 2007/2008
In NASA s Vision for Space Exploration, humans will once again travel beyond the confines of earth s gravity, this time to remain there for extended periods. These forays will place unprecedented demands on launch systems. They must not only blast out of earth s gravity well as during the Apollo moon missions, but also launch the supplies needed to sustain a larger crew over much longer periods. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. This paper describes efforts to improve on typical packed beds of sorbent pellets by making use of structured sorbents and alternate bed configurations to improve system efficiency and reliability. The development efforts described offer a complimentary approach combining testing of subscale systems and multiphysics computer simulations to characterize the regenerative heating substrates and evaluation of engineered structured sorbent geometries. Mass transfer, heat transfer, and fluid dynamics are included in the transient simulations
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