117 research outputs found
Cultures of (In)Security in comparison: From Comparative Literature to Critical Approaches to Security Studies
info:eu-repo/semantics/publishedVersio
Identification of a bitter-taste receptor gene repertoire in different Lagomorphs species
The repertoires of bitter-taste receptor (T2R) gene have been described for several
animal species, but these data are still scarce for Lagomorphs. The aim of the present
work is to identify potential repertoires of T2R in several Lagomorph species, covering a
wide geographical distribution. We studied these genes in Lepus timidus, L. europaeus,
Oryctolagus cuniculus algirus, Romerolagus diazi, and Sylvilagus floridanus, using
O. cuniculus cuniculus as control species for PCR and DNA sequencing. We studied
the identities of the DNA sequences and built the corresponding phylogenetic tree.
Sequencing was successful for both subspecies of O. cuniculus for all T2R genes
studied, for five genes in Lepus, and for three genes in R. diazi and S. floridanus. We
describe for the first time the partial repertoires of T2R genes for Lagomorphs species,
other than the common rabbit. Our phylogenetic analyses indicate that sequence
proximity levels follow the established taxonomic classification
ILS2 Sessions 14 & 16 overview: Frontiers in legume agronomy
Recent developments within legume agronomy were presented in two sessions. An important current focus in legume agronomy is on intercrops or crop mixtures of legumes and grasses / cereals, especially among European scientists. The quantification of legume services in cropping systems and participatory research approaches are other issues gaining interest.Non peer reviewe
Maize open-pollinated populations physiological improvement: validating tools for drought response participatory selection
Participatory selection—exploiting specific adaptation traits to target environments—helps
to guarantees yield stability in a changing climate, in particular under low-input or organic production.
The purpose of the present study was to identify reliable, low-cost, fast and easy-to-use tools to
complement traditional selection for an e ective participatory improvement of maize populations
for drought resistance/tolerance. The morphological and eco-physiological responses to progressive
water deprivation of four maize open-pollinated populations were assessed in both controlled and
field conditions. Thermography and Chl a fluorescence, validated by gas exchange indicated that the
best performing populations under water-deficit conditions were ‘Fandango’ and to a less extent
‘Pigarro’ (both from participatory breeding). These populations showed high yield potential under
optimal and reduced watering. Under moderate water stress, ‘Bilhó’, originating from an altitude of
800 m, is one of the most resilient populations. The experiments under chamber conditions confirmed
the existence of genetic variability within ‘Pigarro’ and ‘Fandango’ for drought response relevant for
future populations breeding. Based on the easiness to score and population discriminatory power,
the performance index (PIABS) emerges as an integrative phenotyping tool to use as a refinement of
the common participatory maize selection especially under moderate water deprivationinfo:eu-repo/semantics/publishedVersio
Polyphenol oxidase activity and colour changes of ‘Starking’ Apple cubes coated with alginate and dehydrated with air
The objective was to study the effect of alginate coating on polyphenol oxidase (PPO) activity and colour of ‘Starking’ apple cubes during dehydration with hot air. Apple cubes were dehydrated at 20°C, 35°C or 40°C, with a parallel air-flow. Analysis of PPO activity, colour (L*, a*, b*) and dry matter were performed along the dehydration process at each temperature. All samples presented a peak in relative PPO activity in the beginning of the drying. Exponential models fitted well the experimental data after the peak. Cubes without coating presented lower PPO activity, suggesting lower browning than coated samples throughout the dehydration process, for all temperatures. Better results for coated samples were obtained with a perpendicular airflow drying at 40°C, after dipping the whole apple in water at 60°C for 10 minutes. In order to prevent coated samples from browning, drying by perpendicular airflow preceded by a thermal treatment of the whole apple is required.info:eu-repo/semantics/publishedVersio
Valorização e potenciais aplicações de uma amostra de própolis português da Beira Alta
O própolis é um produto elaborado pelas abelhas a partir de exsudados de plantas, usado
na proteção da colmeia[1]. Tem sido muito estudado e valorizado mundialmente pelas suas
propriedades biológicas, como a antioxidante e antimicrobiana, atribuídas principalmente
a uma composição química rica em compostos fenólicos. A existência de vários tipos de
própolis – determinados por diferentes tipos de flora e clima - salienta a necessidade da
sua caracterização química e biológica[1]. A padronização do própolis é também requerida
pela sua potencial utilização nas indústrias farmacêutica, cosmética ou alimentar[2]
.
Neste trabalho estudou-se uma amostra de própolis português para verificar o potencial
benefício da sua incorporação em produtos cosméticos. Partiu-se de uma amostra
recolhida num apiário da Beira Alta (Pereiro), em 2015, e procedeu-se à sua extração e
reconstituição em diferentes solventes (etanol 100 % e 70 % e propilenoglicol). Os extratos
(P15.EE100, P15.EE70 e P15.PGE) foram analisados quanto ao seu conteúdo de compostos
fenólicos e flavonóides totais por métodos espetrofotométricos. Adicionalmente, os
constituintes fenólicos individuais de P15.EE100 foram elucidados por análise de
cromatografia liquida por fase reversa, associada a detetor de arrastamento de díodos e a
espetrómetro de massa com ionização por eletrospray (UHPLC-DAD-ESI-MSn). Na
avaliação do potencial antioxidante recorreu-se à medição da atividade scavenging dos
radicais 2,2-difenil-1-picrilhidrazilo e do anião superóxido. A atividade antimicrobiana foi
avaliada pelo método de diluição em agar. P15.EE100 revelou maior teor de polifenóis e
flavonóides totais e também melhor capacidade antioxidante. P15.EE100 exibiu melhor
atividade antibacteriana, particularmente contra bactérias Gram-positivas; P15.EE100 e
P15.EE70 revelaram idêntica atividade antifúngica, com um MIC de 500 μg.mL-1
.
Paralelamente à análise laboratorial estudou-se a indústria e o mercado da cosmética (em
particular o segmento natural e orgânico) e o mercado do própolis. Os dados revelam que,
nos últimos 20 anos, a indústria cosmética apresentou uma taxa de crescimento de
aproximadamente 4,5 % por ano. O mercado global do segmento natural e orgânico tem
aumentado significativamente, prevendo-se um crescimento anual de 10 %[3]
.
Relativamente ao mercado do própolis, prevê-se uma taxa de crescimento de 2,2 % até
2021[4]. Conjugando a análise da indústria cosmética com os resultados laboratoriais
obtidos, em particular as propriedades antimicrobianas e antioxidantes reveladas pelo
própolis estudado, perspetiva-se a possibilidade da sua aplicação em cosméticos
Valorização comercial de uma amostra de própolis do Gerês (Portugal)
O própolis e um material resinoso produzido por abelhas a partir de exsudados de plantas. Tem vindo a ser considerado um produto de excelência visto exibir inúmeras propriedades biológicas[1] . Atualmente, a dimensão do mercado global do própolis e avaliado em cerca de 2300 toneladas e estima-se atingir as 2900 toneladas em 2021, revelando-se um mercado promissor para utilizações nas indústrias farmacêutica, cosmética, alimentar e na apiterapia [2]. Porem, própolis de diferentes regiões geográficas podem apresentar diferentes composições químicas e, portanto, um perfil de propriedades biológicas distinto e/ou atividades específicas com eficiências muito distintas
Extended Spectrum Beta-Lactamase-Producing Gram-Negative Bacteria Recovered From an Amazonian Lake Near the City of Belém, Brazil
Aquatic systems have been described as antibiotic resistance reservoirs, where water may act as a vehicle for the spread of resistant bacteria and resistance genes. We evaluated the occurrence and diversity of third generation cephalosporin-resistant gram-negative bacteria in a lake in the Amazonia region. This water is used for human activities, including consumption after appropriate treatment. Eighteen samples were obtained from six sites in October 2014. Water quality parameters were generally within the legislation limits. Thirty-three bacterial isolates were identified as Escherichia (n = 7 isolates), Acinetobacter, Enterobacter, and Klebsiella (n = 5 each), Pseudomonas (n = 4), Shigella (n = 3), and Chromobacterium, Citrobacter, Leclercia, Phytobacter (1 isolate each). Twenty nine out of 33 isolates (88%) were resistant to most beta-lactams, except carbapenems, and 88% (n = 29) were resistant to antibiotics included in at least three different classes. Among the beta-lactamase genes inspected, the blaCTX–M was the most prevalent (n = 12 positive isolates), followed by blaTEM (n = 5) and blaSHV (n = 4). blaCTX–M–15 (n = 5), blaCTX–M–14 (n = 1) and blaCTX–M–2 (n = 1) variants were detected in conserved genomic contexts: blaCTX–M–15 flanked by ISEcp1 and Orf477; blaCTX–M–14 flanked by ISEcp1 and IS903; and blaCTX–M–2 associated to an ISCR element. For 4 strains the transfer of blaCTX–M was confirmed by conjugation assays. Compared with the recipient, the transconjugants showed more than 500-fold increases in the MICs of cefotaxime and 16 to 32-fold increases in the MICs of ceftazidime. Two isolates (Escherichia coli APC43A and Acinetobacter baumannii APC25) were selected for whole genome analysis. APC43A was predicted as a E. coli pathogen of the high-risk clone ST471 and serotype O154:H18. blaCTX–M–15 as well as determinants related to efflux of antibiotics, were noted in APC43A genome. A. baumannii APC25 was susceptible to carbapenems and antibiotic resistance genes detected in its genome were intrinsic determinants (e.g., blaOXA–208 and blaADC–like). The strain was not predicted as a human pathogen and belongs to a new sequence type. Operons related to metal resistance were predicted in both genomes as well as pathogenicity and resistance islands. Results suggest a high dissemination of ESBL-producing bacteria in Lake Água Preta which, although not presenting characteristics of a strongly impacted environment, contains multi-drug resistant pathogenic strains
A collection of indigenous saccharomyces cerevisiae strains from appellations of origin in Portugal and France
Apresentação efectuada nas "Jornadas Portuguesas de Genética, 35, Braga, 2010"The model organism Saccharomyces cerevisiae stands today at the forefront of molecular biology and functional analysis in genetics and genomics. However, understanding of the ecological, evolutionary and population genetic features that shaped the biology of this species is underscored by a wealth of knowledge on molecular and cellular biology obtained from a very limited number of laboratory strains. In this reasoning, we constituted one of the largest bio-databanks of S. cerevisiae that were obtained from winemaking environments in Portugal and France.
During the harvest time of 2001 to 2009, 604 grape samples were collected in appellations of origin in Portugal (Vinho Verde, Dão, Douro, Bairrada, Estremadura, Palmela, Ribatejo, Açores) and France (Languedoc). The grape samples belonged to the varieties Alvarinho, Aragonez, Arinto, Avesso, Baga, Bical, Castelão, Carignan, Loureiro, Maria Gomes, Terrantez, Touriga Nacional and Verdelho. Yeast populations, in particular S. cerevisiae, were isolated after spontaneous fermentation of the extracted grape juice. From the final stage of 258 fermentations, 7740 yeast isolates were obtained, belonging mainly (5496 isolates) to the species S. cerevisiae. An initial genetic screen, based on mitochondrial DNA restriction fragment length polymorphism (mtDNA RFLP), electrophoretic karyotyping or interdelta sequence analysis, was followed by microsatellite analysis of strains with unique genetic profiles. Isolates were assigned to 752 different strains, based on their microsatellite allelic distribution. The resulting web-based autochthonous strain collection is one of the largest S. cerevisiae bio-databanks and is a resource for sustainable biodiversity preservation, equitable sharing of genetic data and winemaking strain selection.Fundação para a Ciência e Tecnologia (FCT)Direcção Regional da Ciência e Tecnologia (DRCT
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