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Publications

Publications by CRIIS

2008

Feasability of yeast and bacteria identification using UV-VIS-SWNIR difusive reflectance spectroscopy

Authors
Silva, JS; Martins, RC; Vicente, AA; Teixeira, JA;

Publication
BIOSIGNALS 2008: PROCEEDINGS OF THE FIRST INTERNATIONAL CONFERENCE ON BIO-INSPIRED SYSTEMS AND SIGNAL PROCESSING, VOL 1

Abstract
UV-VIS spectroscopy is a powerfull qualitative and quantitative technique used in analytical chemistry, which gives information about electronic transitions of electrons in molecular orbitals. As in UV-VIS spectra there is no direct information on characteristic organic groups, vibrational spectroscopy (e.g. infrared) has been preferred for biological applications. In this research, we try to use state-of-the-art fiber optics probes to obtain UV-VIS-SWNIR diffusive reflectance measurements of yeasts and bacteria colonies on plate count agar in the region of 200-1200nm; in order to discriminate the following microorganisms: i) yeasts: Saccharomyces cerevisiae, Saccharomyces bayanus, Candida albicans, Yarrowia lipolytica; and ii) bacteria: Micrococcus luteus, Pseudomonas fluorescens, Escherichia coli, Bacillus cereus. Spectroscopy results show that UV-VIS-SWNIR has great potential for identifying microorganisms on plate count agar. Scattering artifacts of both colonies and plate count agar can be significantly removed using a robust mean scattering algorithm, allowing also better discriminations between the scores obtained by singular value decomposition. Hierarchical clustering analysis of UV-VIS and VIS-SWNIR decomposed spectral scores lead to the conclusion that the use of VIS-SWNIR light source produces higher discrimination ratios for all the studied microorganisms, presenting great potential for developing biotechnology applications.

2008

The importance of plantain (Plantagospp.) as a supplementary pollen source in the diet of honey bees

Authors
Sabugosa-Madeira, B; Ribeiro, H; Cunha, M; Abreu, I;

Publication
Journal of Apicultural Research

Abstract

2008

The newest generation of Paul Wurth bell-less top® blast furnace charging systems

Authors
Brinckmann, J; Dele, R; Goffin, R; Kinsch, P; Thillen, G; Cunha, M;

Publication
ANNALS - 3rd International Meeting on Ironmaking and 2nd International Symposium on Iron Ore

Abstract
The Paul Wurth Bell-Less Top® (BLT) is the industrial standard for iron blast furnace charging systems. Since Paul Wurth's invention of the BLT in the early 1970s the system has evolved with the changes in iron-making technologies and market conditions. With the latest demands for high charging equipment availability and maintainability - new developments have been recently implemented. The paper will cover the evolution of the Bell-Less Top®, the latest operational requirements and the latest new developments and solutions.

2008

Quantitative forecasting of olive yield in Northern Portugal using a bioclimatic model

Authors
Ribeiro, H; Cunha, M; Abreu, I;

Publication
AEROBIOLOGIA

Abstract
In this work the objective was to develop a bioclimatic model to forecast olive yield based on airborne pollen, soil water content, and favourable conditions for phytopathological attacks. Olive airborne pollen was sampled from 1998 to 2006 using Cour traps installed in the Tras-os-Montes e Alto Douro region, in the provinces of Valenca do Douro and Vila Nova de Foz-Coa. Meteorological data from a meteorological station located in Pinhao, near the pollen samplers, was used to calculate other independent variables. According to the bioclimatic model, at the flowering stage 63% of regional olive production can be predicted from the regional pollen index, with an average deviation between observed and predicted production of 10%. The variable soil water content enabled an increase in forecasting accuracy of about 30%, and a reduction in the average deviation between observed and predicted production of 6%. The final regression with all three variables tested showed that the bioclimatic model was able to predict the annual variability of regional olive fruit production with an accuracy of 97%, the average deviation between observed and predicted production being 3% for internal validation and 6% for external validation.

2008

Anemophilous and entomophilous pollen flows of Castanea sativa in the Northeast of Portugal

Authors
Sabugosa Madeira, B; Ribeiro, H; Cunha, M; Abreu, I;

Publication
PROCEEDINGS OF THE SECOND IBERIAN CONGRESS ON CHESTNUT

Abstract
The impact of climatic changes can be evaluated by analysing the long-trends of plant phenological events. The airborne pollen sampling and the study of Apis mellifera L. (honeybee) collected pollen are two methodologies that can be used to survey the date of occurrence of the flowering phase. The aim of the present work was to compare the anemophilous and entomophilous pollen flows of Castanea sativa (chestnut tree) in two regions of the north-west of Portugal. The synchronism between the airborne samples and the honeybee samples was confirmed by the significant positive correlation between them. The inter-annual variations in the beginning and peak dates of pollen flows were very similar although an anticipation was observed in the honeybees.

2008

The importance of plantain (Plantago spp.) as a supplementary pollen source in the diet of honey bees

Authors
Sabugosa Madeira, B; Ribeiro, H; Cunha, M; Abreu, I;

Publication
JOURNAL OF APICULTURAL RESEARCH

Abstract
Plantain (Plantago spp.) is generally considered to be an anemophilous plant that produces pollen of low nutritional value to bees. Between April and September during 2002 and 2003, in two regions in northwestern Portugal, we studied both the pollen collected by honey bee colonies and airborne pollen. Plantain pollen collection by honey bees was observed only in three different periods, despite its continuous presence in the air. This behaviour was related to the beginning and ending of flowering of the honey bee's main nutritional pollen sources, with no other factor seemingly influencing the temporal collecting patterns. The collection of Plantago spp. pollen was observed in the gaps between the flowering of Eucalyptus spp., chestnut (Castanea sativa), wild blackberry (Rubus spp.) and heaths (Ericaceae family). The results suggest that pollen of Plantago species seems to be used by honey bees as a substitute for other more nutritious pollen types and is collected only as a supplementary source. The temporal patterns of Plantago pollen collection by honey bees could therefore be used as a valuable ecological indicator of periods with low availability of highly nutritious pollen sources.

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