42 research outputs found
Note. Colonisation of bench cover materials by Salmonella typhimurium
Due to the increasing requirements of food safety, it is of utmost importance to know the mechanisms that can determine the occurrence of the phenomenon commonly assigned by cross contamination, which can be expressed by the transference of harmful substances or microorganisms to the human food chain.
This is particularly susceptible during food preparation, because it can occur by the transference of the pathogen microorganisms from food to the surfaces where they had been prepared, and from
there to foods initially not contaminated, therefore initiating the cycle. This study attempted to investigate the colonisation by Salmonella typhimurium ATCC 13311 of marble and granite, two materials commonly used as bench covers in kitchens of many countries. These materials were selected because there is a lack of studies in the literature about their ability for bacterial colonisation. In addition, the colonisation of stainless steel (SS) 304, a material usually studied, was also analysed in terms of comparison.
Surface hydrophobicity and roughness were determined in order to explain the differences in the extent of adhesion. The results showed that SS was the material with a greater extent of colonisation by S. typhimurium, followed by marble and, almost to the same extent, by granite. S. typhimurium adheres to a greater extent to the most hydrophobic material and to the material with roughest surface.Fundação para a Ciência e a Tecnologia (FCT) - PRAXIS SFRH/BPD/11553/2002, projecto POCI/AGR/59358/200
Avaliação da presença de coliformes, bolores e leveduras em amostras de mel orgânico de abelhas africanizadas das ilhas do alto rio Paraná.
O presente trabalho foi desenvolvido para caracterizar a microbiota do mel produzido nas ilhas Floresta e Laranjeira do alto rio Paraná, na região de Porto Brasílio, Paraná (PR). O mel foi coletado diretamente das melgueiras das colônias avaliadas, em três apiários distribuídos nas ilhas Floresta e Laranjeira. O período de coleta das amostras de mel foi de novembro de 2005 a fevereiro de 2006, perfazendo o total de 24 amostras de mel orgânico produzido por abelhas Apis mellifera africanizadas. Seguindo o método das normas internacionais da Compendium of Methods for the Microbiology Examination of Foods, os parâmetros analisados foram: presença de coliformes a 35°C e 45°C e quantificação de bolores e leveduras. Verificou-se que todas as amostras apresentaram-se em conformidade com o Regulamento Técnico MERCOSUL de Identidade e Qualidade do Mel (MERCOSUL/GMC/RES no 15/94). As amostras analisadas indicaram excelente qualidade microbiológica para o mel orgânico
Morphology and foliar chemistry of containerized Abies fraseri (Pursh) Poir. seedlings as affected by water availability and nutrition
• We present the results of a two-year (2007–2008) greenhouse study investigating the
effect of water availability and nitrogen fertilization on the growth, biomass
partitioning, and foliar nutrient content of Abies fraseri (Pursh)
Poir.
• Fertilizer and moisture content (irrigation) were varied in a factorial experiment
combining four levels of irrigation and three levels of fertilization to evaluate growth
and foliar nutrient content. In addition, a numerical optimization was used to estimate
appropriate levels of each factor necessary to achieve simulated goals for response
variables.
• Irrigation increased the height growth by 12 to 35% depending on the fertilization
treatment (p = 0.0001). Fertilization increased height growth by 10 to
26% (p = 0.02). A similar response was observed for stem diameter growth
(SDG). Total biomass accumulation increased as result of positive response of stem and
root biomass development, and foliar nitrogen content was positively affected by nitrogen
fertilization and negatively affected by irrigation. The numerical optimization for
simulated target growth and nitrogen content responses produced levels of input
combinations with high desirability factors to achieve the target responses.
• These results suggest that nutrient addition is a strong determining factor for early
development of this species. The improved growth efficiency in this study is likely
attributed to a combination of factors including, improved photosynthetic capacity,
decreased stomatal limitations, or increased resource allocation to stems
Morphology and foliar chemistry of containerized Abies fraseri (Pursh) Poir. seedlings as affected by water availability and nutrition
Necrotrophic fungi associated with epidermal microcracking caused by chilling injury in pickling cucumber fruit
The Two-Dimensional Content of Consciousness
In this paper I put forward a representationalist theory of conscious experience based on Robert Stalnaker's version of two-dimensional modal semantics. According to this theory the phenomenal character of an experience correlates with a content equivalent to what Stalnaker calls the diagonal proposition. I show that the theory is closely related both to functionalist theories of consciousness and to higher-order representational theories. It is also more compatible with an anti-Cartesian view of the mind than standard representationalist theories.</p
La fertilisation en pépinière affecte la tolérance au froid et la qualité des plants bouturés d’Eucalyptus globulus Labill
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