Incidence and pathogenicity of Fusarium species associated with temperate cereals in East Scotland

In a survey of the incidence of Fusarium species on plants from cereal, fungicide- trial plots in the east o f Scotland, carried out in 1987 and 1988, F. culmorum was the most prevalent pathogenic species and F. dimerum the most frequently occurring saprophyte. The form er species was generally distributed over roots, stems and ears but F. dimerum was confined to roots and stems. High infection levels o f other pathogens, F. avenaceum and F. nivale, and o f the weak pathogens, F. poae and F. sambucinum, were found only sporadically. Fusariumspecies occurring in slight or traces amounts included, F. graminearum, F.moniliforme, recognized pathogens o f cereals, F. equiseti, F. sporotrichioidesand F. tricinctum, weak pathogens, and F. acuminatum, F. oxysporum, F.semitectum, F. solani andF. sulphureum which are non-pathogenic to cereals. Fungal genera, other than Fusarium, which were prevalent included Cylindrocarpon on roots, Mucor on stems and Cladosporium on ears. Trichothecium roseum was frequent in some crops and attracted interest as a potential antagonist o f Fusarium and as a potential plant pathogen. Fungicide treatments applied to plots to control m ainly cereal leaf diseases were found to have a beneficial side effect in often giving a moderate reduction in Fusariuminfection. However, it is suggested that this field exposure o f Fusarium pathogens to fungicides may predispose towards future insensitivity problem s. In vitro tests on the response o f different Fusarium species to triadim enol fungicides showed a greater sensitivity in F. nivale and F. dimerum compared w ith other species which may be linked w ith their distinctive taxonom ic grouping. The low incidence oiF. nivale in the survey relative to that reported by earlier workers may be attributed in part to the more frequent application o f fungicides to cereal crops in the field and the sensitivity o f this fungus to the w idely used triadim enol- containing form ulations. A further factor accounting for the unexpectedly low incidence o f/7, nivale may have been the relatively m ild winters and warm summers over the period o f this survey which w ould be unfavourable to this low tem perature fungus. From artificial inoculation o f ears o f different cereals with Fusarium species, F. culmorum, followed by F. avenaceum and F. graminearumwere shown to depress grain yield significantly, F. culmorum having a m ajor effect on grain size and the other two species causing a decrease in grain numbers. Earlier inoculations during the flowering period aggravated the effects o f infection. The introduction o f T. roseum 1 week before inoculation reduced these effects. The carry-over o f ear inoculated Fusarium on seed was generally greater w ith the m ore pathogenic species, which also showed m ore deep-seated infection. However, the weak pathogen F. sambucinum also showed a high rate o f carry-over and deeper penetration o f seed tissues. Seed and soil inoculation tests confirm ed th a t/7, culmorum was the most pathogenic species, followed by F.avenaceum and F. graminearum. The addition o f T. roseum to Fusariuminoculum adversely affected seed perform ance but other fungi, an isolate of Penicillium and o f Cladosporium, reduced disease effects

Opportunities and threats for the launch of a smartphone app

Field lab: Entrepreneurial and innovative venturesThe following work project illustrates the opportunities and threats of the industry for the launch of a smartphone app. In the first part, the technological and economic contextual drivers are analyzed in-depth through the study of key variables for the proliferation of the industry. In the second part, the characteristics of the market are exposed through a market assessment including an analysis of the industry rivalry and industry mapping. The political, legal and ethical concerns emergent from the launch of a new smartphone app are then illustrated with the use of two case studies

Farmer Management of Maize Diversity in the Central Valleys of Oaxaca, Mexico: CIMMYT/INIFAP 1998 Baseline Socioeconomic Survey

Crop Production/Industries,

El Alto y el Bajo Imperio

Síntesis arqueológica de las comarcas castellonenses entre los periodos romano y visigótico

SEM image analysis in permeable recycled concretes with silica fume. A quantitative comparison of porosity and the ITZ

Recycled aggregates (RA) from construction and demolition can be used in permeable concretes (PC), improving the environment. PCs have a significant porous network, their cement paste and the interaction between the paste and the RA establishing their strength. Therefore, it is important to evaluate the porosity in the interfacial transition zones. The porosity of the cement paste, the aggregate and the interfacial transitional zones (ITZ) of a PC with recycled coarse aggregates (RCA) and silica fume (SF) is measured by means of image analysis–scanning electron microscope (IA)-(SEM) and by mapping the chemical elements with an SEM-EDS (energy dispersive spectrometer) detector microanalysis linked to the SEM and, as a contrast, the mercury intrusion porosimetry technique (MIP). In the IA process, a “mask” was created for the aggregate and another for the paste, which determined the porosity percentage (for the anhydrous material and the products of hydration). The results showed that using SF caused a reduction (32%) in the cement paste porosity in comparison with the PC with RA. The use of RA in the PC led to a significant increase (190%) in the porosity at different thicknesses of ITZ compared with the reference PC. Finally, the MIP study shows that the use of SF caused a decrease in the micropores, mesopores and macroporesPeer ReviewedPostprint (published version

Geometrical constraints on dark energy models

This contribution intends to give a pedagogical introduction to the topic of dark energy (the mysterious agent supposed to drive the observed late time acceleration of the Universe) and to various observational tests which require only assumptions on the geometry of the Universe. Those tests are the supernovae luminosity, the CMB shift, the direct Hubble data, and the baryon acoustic oscillations test. An historical overview of Cosmology is followed by some generalities on FRW spacetimes (the best large-scale description of the Universe), and then the test themselves are discussed. A convenient section on statistical inference is included as well.Comment: 28 pages, 15 pages, lecture notes prepared for the ``Advanced Summer School in Physics 2007" organized by Cinvestav (Mexico DF

Potential distributional patterns of three wild ungulate species in a fragmented tropical region of northeastern Mexico

"In the northernmost American tropical forests of eastern Mexico, we analyzed the potential distribution of three ungulate species, Odocoileus virginianus, Mazama temama and Pecari tajacu, in response to several physical, climatic, biological, and anthropogenic variables, in order to identify environmental factors affecting distribution and potential key areas for ungulate conservation. Current presence records for these species were gathered, and potential distribution models were built using Maximum Entropy niche modeling (MaxEnt). Model suitability surfaces were used to calculate remaining potential habitat areas in the region, as well as the potential sympatric area and representation of these areas in Natural Protected Areas. Biological and anthropogenic variables were the best species distribution predictors. Landscape composition (the proportion of different land-use and land-cover classes: forest, agriculture, and pasture) within approximately 120 ha, was the most important variable for all models, influencing each species differently with respect to their tolerance of altered habitats. The remaining potential area of all three species is fragmented and has apparently been nearly lost in plains (<14% remaining). Distribution models allowed us to detect an important location in the western portion of our study area which may function as a large biological corridor in the Sierra Madre Oriental mastogeographic province, a region heavily transformed by land use change. In the context of habitat transformation, management promoting quality matrix at the landscape level promises to be a viable alternative for ungulate conservation in tropical regions of Mexico.

Environmental tobacco smoke exposure and smoking habits in a secondary school

O conhecimento de que o tabagismo activo tem efeitos nefastos na saúde não é novidade, mas a investigação têm-se voltado igualmente para o estudo do impacto da exposição ao Fumo de Tabaco Ambiental (FTA). No presente estudo descritivo de painel procura-se sensibilizar para a importância de promover a escola como um local livre de tabaco, procurando-se estudar os hábitos tabágicos, a exposição ao FTA, o incómodo resultante dessa exposição, a percepção de nocividade do fumo de tabaco e o grau de concordância com políticas preventivas, de professores, funcionários e alunos de uma escola secundária. Os dados revelam uma percentagem significativa de fumadores dentro do espaço escola, e uma exposição diária pela maior parte dos professores, funcionários e alunos ao FTA, quer em espaços interiores e exteriores, sendo notável o incómodo provocado por esta exposição. Verifica-se também que a maioria concorda com as políticas de prevenção e restrição do tabagismo dentro da escola. Posto isto, discute-se a necessidade e a viabilidade de implementar esses políticas do consumo de tabaco neste contexto escolar

Comparación de la resistencia en Kg/Cmͣ2 del concreto común y el concreto con ceniza de cáscara de café como sustituto porcentual del agregado fino

En la actualidad, dentro del sector construcción, las técnicas constructivas en general y la reutilización de los materiales de desecho, surge la posibilidad del empleo de materiales alternativos dentro de la construcción que permiten reducir la extracción y uso de ciertos materiales convencionales, ante esto, se presenta la necesidad de seguir investigando en el campo de la tecnología de materiales que permitan no solamente reducir los costos de adquisición de los mismos, sino que también permitan mejorar las propiedades de los elementos de concreto. En esta investigación se analizó la resistencia a la compresión del concreto f’c=210kg/cm2, sustituyendo el 5%, 8% y 10% en peso del agregado fino por ceniza de cáscara de café, realizando posteriormente ensayos en el estado endurecido del concreto con el objetivo de determinar el mejor comportamiento de este material, identificando las diferencias y el nivel de significancia de las mismas, haciendo uso de la prueba de Tukey, Duncan y Dunnet a través de métodos de comparación múltiple.Tesi