181 research outputs found

    Current insights into the effects of cationic biocides exposure on Enterococcus spp.

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    Cationic biocides (CBs), such as quaternary ammonium compounds and biguanides, are critical for controlling the spread of bacterial pathogens like Enterococcus spp., a leading cause of multidrug-resistant healthcare-associated infections. The widespread use of CBs in recent decades has prompted concerns about the potential emergence of Enterococcus spp. populations exhibiting resistance to both biocides and antibiotics. Such concerns arise from their frequent exposure to subinhibitory concentrations of CBs in clinical, food chain and diverse environmental settings. This comprehensive narrative review aimed to explore the complexity of the Enterococcus response to CBs and of their possible evolution toward resistance. To that end, CBs activity against diverse Enterococcus spp. collections, the prevalence and roles of genes associated with decreased susceptibility to CBs, and the potential for co- and cross-resistance between CBs and antibiotics are reviewed. Significant methodological and knowledge gaps are identified, highlighting areas that future studies should address to enhance our comprehension of the impact of exposure to CBs on Enterococcus spp. populations epidemiology. This knowledge is essential for developing effective One Health strategies that ensure the continued efficacy of these critical agents in safeguarding Public Health.</jats:p

    Miocene sediments from Foz da Fonte and Penedo sections (Lower Tagus basin): clay minerals and isotopic data

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    Eight depositional sequences (DS) delimited by regional disconformities had been recognized in the Miocene of Lisbon and SetĂşbal Peninsula areas. In the case of the western coast of the SetĂşbal Peninsula, outcrops consisting of Lower Burdigalian to Lower Tortonian sediments were studied. The stratigraphic zonography and the environmental considerations are mainly supported on data concerning to foraminifera, ostracoda, vertebrates and palynomorphs. The first mineralogical and geochemical data determined for Foz da Fonte, Penedo Sul and Penedo Norte sedimentary sequences are presented. These analytical data mainly correspond to the sediments' fine fractions. Mineralogical data are based on X-ray diffraction (XRD), carried out on both the less than 38 nm and 2 nm fractions. Qualitative and semi-quantitative determinations of clay and non-clay minerals were obtained for both fractions. The clay minerals assemblages complete the lithostratigraphic and paleoenvironmental data obtained by stratigraphic and palaeontological studies. Some palaeomagnetic and isotopic data are discussed and correlated with the mineralogical data. Multivariate data analysis (Principal Components Analysis) of the mineralogical data was carried out using both R-mode and Q-mode factor analysis

    Quantification of endogenous auxin levels and polyphenoloxidase enzymatic activity in olive (Olea europaea L.)

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    A actividade enzimåtica de polifenoloxidases foi avaliada em folhas e na zona apical, mÊdia e basal de ramos de duas cultivares de oliveira (Olea europaea L.), comuns no Alentejo ( Galega vulgar e Cobrançosa ), mostrando que a actividade enzimåtica nas folhas foi muito superior à encontrada em tecidos de ramos do ano. Maior actividade enzimåtica foi tambÊm detectada na variedade Cobrançosa versus Galega vulgar . As condiçþes óptimas para a determinação da actividade enzimåtica foram: pH= 5.5 e T= 40 ºC, com 20 mM de 4-metilcatecol em tampão acetato. Nestas condiçþes o KM determinado foi: 2,60 e 3,48 mM com o mÊtodo de Michaelis-Menten e Lineweaver-Burk, respectivamente. A melhor recuperação das auxinas AIA (åcido indol-3-acÊtico) e AIB (åcido indolbutírico) em material vegetal foi conseguida atravÊs da extracção das amostras com acetona. A separação, identificação e quantificação do AIA e AIB em padrþes, material vegetal dopado (tecidos de oliveira dopados com uma concentração conhecida de padrão) e não dopado, foi efectuada por tÊcnicas cromatogråficas (HPLC-DAD e LCMS), mostrando os resultados taxas de recuperação superiores a 40% para o AIA e 60% para o AIB

    OLIVESIM: Gestão dos serviços de ecossistema no olival utilizando modelos espaciais avançados

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    Poster apresentado no Congresso PolitĂŠcnico SetĂşbal - 40 anos a construir o futuro, 3-4 outubro 2019, SetĂşbal, PortugalN/

    Performance of the LHCb muon system with cosmic rays

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    The LHCb Muon system performance is presented using cosmic ray events collected in 2009. These events allowed to test and optimize the detector configuration before the LHC start. The space and time alignment and the measurement of chamber efficiency, time resolution and cluster size are described in detail. The results are in agreement with the expected detector performance.Comment: Submitted to JINST and accepte

    Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

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    Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe
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