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9981. Select result number 9981
      9981
      

      Nominalization, event, aspect, and argument structure : a syntactic approach

      Publication

      book Portugal Open access

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9982. Select result number 9982
      9982
      

      Caracterização do Incesto Paternal no Norte de Portugal

      Publication

      master thesis Portugal Open access

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9983. Select result number 9983
      9983
      

      Análise da sonolência através da monitorização do condutor em simulador de condução

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      conference object Portugal Open access

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9984. Select result number 9984
      9984
      

      Carbidopa alters tryptophan metabolism in breast cancer and melanoma cells leading to the formation of indole-3-acetonitrile, a pro-proliferative metabolite

      Publication

      Carbidopa is used for the treatment of Parkinson’s disease (PD) as an inhibitor of DOPA decarboxylase, and PD patients taking carbidopa have a lower incidence of various tumors, except for breast cancer andmelanoma. Recently, itwas shown that carbidopa inhibits tryptophan-2,3-dioxygenase (TDO) and kynureninase enzymes. In the present study, the effect of carbidopa on the viability and metabolic profile of breast cancer MCF-7 and melanoma A375 cells was investigated. Carbidopa was not effective in inhibiting MCF-7 and A375 proliferation. Liquid chromatography and mass spectrometry revealed a new compound, identified as indole-3-acetonitrile (IAN), which promoted a concentration-dependent increase in the viability of both cell lines. The results suggest that treatment with carbidopa may alter tryptophan (Trp) metabolism in breast cancer and melanoma leading to the formation of a pro-proliferative Trp metabolite, which may contribute to its failure in reducing breast cancers and melanoma incidence in PD patients taking carbidopa.

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      journal article Portugal Open access

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9985. Select result number 9985
      9985
      

      Asymptotic distribution of the Yule-Walker estimator for INAR(p) processes

      Publication

      The INteger-valued AutoRegressive (INAR) processes were introduced in the literature by Al-Osh and Alzaid [1987. First-order integer-valued autoregressive (INAR(l)) process. J. Time Ser. Anal. 8, 261-275] and McKenzie [1988. Some ARMA models for dependent sequences of Poisson counts. Adv. Appl. Probab. 20, 822-835] for modelling correlated series of counts. These processes have been considered as the discrete counter part of AR processes, but their highly nonlinear characteristics lead to some statistically challenging problems, namely in parameter estimation. Several estimation procedures have been proposed in the literature, mainly for processes of first order. For some of these estimators the asymptotic properties as well as finite sample properties have been obtained and studied. This paper considers Yule-Walker parameter estimation for the pth-order integer-valued autoregressive, INAR(p), process. In particular, the asymptotic distribution of the Yule-Walker estimator is obtained and it is shown that this estimator is asymptotically normally distributed, unbiased and consistent.

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      journal article Portugal Restricted access

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9986. Select result number 9986
      9986
      

      O sentido não existe: da insistência do sentido no acontecimento vocacional

      Publication

      master thesis Portugal Restricted access

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9987. Select result number 9987
      9987
      

      Algumas considerações sobre a escolha das amas de leite

      Publication

      bachelor thesis Portugal Open access

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9988. Select result number 9988
      9988
      

      Noise reduction and normalization of microblogging messages

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      doctoral thesis Portugal Open access

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9989. Select result number 9989
      9989
      

      Tradutores e intérpretes de língua gestual/de sinais em Portugal e no Brasil: função, formação, deveres e responsabilidades/atribuições

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      journal article Portugal Restricted access

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9990. Select result number 9990
      9990
      

      Sumários e Exames de Física 1 e Física 2, 2015

      Publication

      other Portugal Open access

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9991. Select result number 9991
      9991
      

      Random walks on semaphore codes and delay de Bruijn semigroups

      Publication

      We develop a new approach to random walks on de Bruijn graphs over the alphabet A through right congruences on A(k), defined using the natural right action of A(+). A major role is played by special right congruences, which correspond to semaphore codes and allow an easier computation of the hitting time. We show how right congruences can be approximated by special right congruences.

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      journal article Portugal Open access

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9992. Select result number 9992
      9992
      

      Data-driven modeling of the cellular pharmacokinetics of degradable chitosan-based nanoparticles

      Publication

      Nanoparticle drug delivery vehicles introduce multiple pharmacokinetic processes, with the delivery, accumulation, and stability of the therapeutic molecule influenced by nanoscale pro-cesses. Therefore, considering the complexity of the multiple interactions, the use of data-driven models has critical importance in understanding the interplay between controlling processes. We demonstrate data simulation techniques to reproduce the time-dependent dose of trimethyl chi-tosan nanoparticles in an ND7/23 neuronal cell line, used as an in vitro model of native peripheral sensory neurons. Derived analytical expressions of the mean dose per cell accurately capture the pharmacokinetics by including a declining delivery rate and an intracellular particle degradation process. Comparison with experiment indicates a supply time constant, t = 2 h. and a degradation rate constant, b = 0.71 h-1. Modeling the dose heterogeneity uses simulated data distributions, with time dependence incorporated by transforming data-bin values. The simulations mimic the dynamic nature of cell-to-cell dose variation and explain the observed trend of increasing numbers of high-dose cells at early time points, followed by a shift in distribution peak to lower dose between 4 to 8 h and a static dose profile beyond 8 h.

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      journal article Portugal Open access

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9993. Select result number 9993
      9993
      

      Photocatalytic activity of nanostructured TiO2/carbon-nanotube composites for near-UV to visible water treatment

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      doctoral thesis Portugal Open access

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9994. Select result number 9994
      9994
      

      Optical and Photovoltaic Properties of Thieno[3,2-b]thiophene-Based Push-Pull Organic Dyes with Different Anchoring Groups for Dye-Sensitized Solar Cells

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      journal article Portugal Open access

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9995. Select result number 9995
      9995
      

      Comparison between working and non working chronic dialysis patients

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      conference object Portugal Open access

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9996. Select result number 9996
      9996
      

      Dimensões afetivas na resolução de problemas de matemática no âmbito de uma competição inclusiva

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      master thesis Portugal Open access

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9997. Select result number 9997
      9997
      

      A educação da infância marginalizada na cidade de Penafiel (1865-1974): instituições de acolhimento, assistência e proteção

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      doctoral thesis Portugal Open access

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9998. Select result number 9998
      9998
      

      Das coisas que parecem outras ao toque

      Publication

      master thesis Portugal Open access

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9999. Select result number 9999
      9999
      

      Designing a Framework for GPON Network Development

      Publication

      2027 master thesis Portugal

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10000. Select result number 10000
       10000
       

       Proteomic analyses of the unexplored sea anemone Bunodactis verrucosa

       Publication

       Cnidarian toxic products, particularly peptide toxins, constitute a promising target for biomedicine research. Indeed, cnidarians are considered as the largest phylum of generally toxic animals. However, research on peptides and toxins of sea anemones is still limited. Moreover, most of the toxins from sea anemones have been discovered by classical purification approaches. Recently, high-throughput methodologies have been used for this purpose but in other Phyla. Hence, the present work was focused on the proteomic analyses of whole-body extract from the unexplored sea anemone Bunodactis verrucosa. The proteomic analyses applied were based on two methods: two-dimensional gel electrophoresis combined with MALDI-TOF/TOF and shotgun proteomic approach. In total, 413 proteins were identified, but only eight proteins were identified from gel-based analyses. Such proteins are mainly involved in basal metabolism and biosynthesis of antibiotics as the most relevant pathways. In addition, some putative toxins including metalloproteinases and neurotoxins were also identified. These findings reinforce the significance of the production of antimicrobial compounds and toxins by sea anemones, which play a significant role in defense and feeding. In general, the present study provides the first proteome map of the sea anemone B. verrucosa stablishing a reference for future studies in the discovery of new compounds. © 2018 by the authors.

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       journal article Portugal Open access

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