Epimutations in human sperm from patients with impaired spermatogenesis

CJM is funded by the Portuguese Foundation for Science and Technology (FCT) with a salary contract (IF/00047/2012; CEECIND/00371/2017)

Velocity and structural model of the Lower Tagus Basin according to the study of environmental seismic noise

Along his history the Lower Tagus Valley (LTV) region was shaken by several earthquakes, some of them produced in large ruptures of offshore structures located southwest of the Portuguese coastline. Among these is the Lisbon earthquake of 1 November 1755 (M∼8.5-8.7), and other moderates earthquakes that were produced by local sources such as the 1344 (M6.0), 1531 (M7.1) and 1909 (M6.0) earthquakes. Previous simulations [1] have shown high velocity amplification in the region. The model used in the simulations was updated from low to high resolution using all the new available geophysical and geotechnical data on the area (seismic reflection, aeromagnetic, gravimetric, deep wells and geological outcrops) [2]. To confirm this model in the areas where it was derived by potential field methods we use broadband ambient noise measurements collected in about 200 points along seven profiles on the LTV basin, six perpendicular and one parallel to the basin axis. We applied the horizontal to vertical (H/V) spectral ratio method [3] to the seismic noise profiles in order to estimate the distribution of amplification in the basin. The H/V curves obtained reveals the existence of two low frequency peaks centered on 0.2 and 1 Hz [4]. These peaks are strongly related with the thickness of Cenozoic and alluvial sediments. The velocity model obtained by inversion of the H/V curves is in good agreement with borehole data, and results obtained using seismic reflection and gravimetric methods. However, aeromagnetic data overestimates the depth of the base of Cenozoic in the areas where it overlies directly the paleozoic basement, which we attribute either to the existence of Mesozoic units or higher magnetic susceptibilities than expected for the Paleozoic. References: [1] Bezzeghoud, M., Borges, J.F., M., Caldeira (2011). Ground motion simulations of the SW Iberia margin: rupture directivity and earth structure effects. Natural Hazards, pages 1–17. doi:10.1007/s11069-011-9925-2 [2] Torres, R.J.G., (2012). Modelo de velocidade da Bacia do Vale do Tejo: uma abordagem baseada no estudo do ruído sísmico ambiental, Master Thesis, Universidade de Évora, 83pp. [3] Nakamura, Y., 1989. A method for dynamic characteristics estimations of subsurface using microtremors on the ground surface, Quarterly Report, RTRI, Japan, v. 30, p. 25-33. [4] J.A. Furtado, Confirmação do modelo da estrutura 3D do Vale Inverior do Tejo a partir de dados de ruído sísmico ambiente, Master Thesis, Universidade de Évora, 136pp, 2010

Photoinduced Schottky Barrier in Photorefractive Materials

We report on the first experimental evidence of a Schottky barrier effect produced by the action of light in an otherwise purely Ohmic contact between a nominally undoped photorefractive titanosillenite Bi(12)TiO(20) crystal and a transparent conductive SnO(2) electrode. The photorefractive crystal is sandwiched between two transparent electrodes and a Schottky barrier is built up in the illuminated crystal-electrode interface under the action of light with photonic energy large enough to excite charge carriers from the Fermi level into the conduction band. The contact remains purely Ohmic under illumination with photonic energy below that of the Fermi gap and the photoinduced barrier almost disappears if the photonic energy is large enough to produce electron-hole pairs.1041

Doença Meningocócica Invasiva: Aplicação do Base Excess and Platelets Score numa Unidade de Cuidados Intensivos Pediátricos Portuguesa

INTRODUCTION: Meningococcal infection has a high mortality and morbidity. Recently a new prognostic scoring system was developed for paediatric invasive meningococcal disease, based on platelet count and base excess â base excess and platelets score. The main objective of this study was to evaluate the accuracy of base excess and platelets score to predict mortality in children admitted to intensive care due to invasive meningococcal disease. MATERIAL AND METHODS: Observational study, with retrospective data collection, during a 13.5 years period (01/2000 to 06/2013). Mortality by invasive meningococcal disease and related factors (organ dysfunction and multi-organ failure) were analysed. The base excess and platelets score was calculated retrospectively, to evaluate its accuracy in predicting mortality and compared with Paediatric Risk of Mortality and Paediatric Index of Mortality2. RESULTS: Were admitted 76 children with invasive meningococcal disease. The most frequent type of dysfunction was cardiovascular (92%), followed by hematologic (55%). Of the total, 47 patients (62%) had criteria for multi-organ failure. The global mortality was 16%. Neurologic and renal dysfunction showed the strongest association with mortality, adjusted odds ratio 315 (26 - 3 804) and 155 (20 - 1 299). After application of receiver operating characteristic curves, Base Excess and Platelets score had an area under curve of 0.81, Paediatric Index of Mortality2 of 0.91 and Paediatric Risk of Mortality of 0.96. DISCUSSION: The Base Excess and Platelets score showed good accuracy, although not as high as Paediatric Risk of Mortality or Paediatric Index of Mortality 2. CONCLUSIONS: The Base Excess and Platelets score may be useful tool in invasive meningococcal disease because is highly sensitive and specific and is objectively measurable and readily available at presentation

Equilibrium states for impulsive semiflows

We consider impulsive semiflows defined on compact metric spaces and give sufficient conditions, both on the semiflows and the potential functions, for the existence and uniqueness of equilibrium states. We also generalize the classical notion of topological pressure to our setting of discontinuous semiflows and prove a variational principle

Holographic recording and characterization of photorefractive Bi2TeO5 crystals at 633 nm wavelength light

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)We report on the holographic recording on photorefractive Bi2TeO5 crystals using lambda = 633 nm wavelength light. We studied the behavior of this material under the action of this low photonic energy light and found out the presence of a fast and a slow hologram, both of photorefractive nature and exhibiting rather high diffraction efficiencies. The faster and the slower holograms are based on the excitation and diffusion of oppositely charged carriers (likely electrons and holes). Relevant parameters for the photoactive centers responsible for both kind of holograms were characterized using purely holographic techniques. No evidences of non-photosensitive ionic charge carriers being involved in the recording process at room temperature nor self-fixing effects were found. (C) 2014 AIP Publishing LLC.11516Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundacao de Amparo Pesquisa do Estado de Goias (FAPEG)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundo de Apoio ao Ensino, Pesquisa e Extensao da Universidade Estadual de Campinas (FAEPEX)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Comportamento de Biomphalaria glabrata variantes albina e melânica frente à infecção pelo Schistosoma mansoni

The behaviour of the albino and melanic variants of Biomphalaria glabrata of Belo Horizonte (MG. Brazil) was studied comparatively, in terms of their respective susceptibilities to infection by Schistosoma mansoni of the same origin, through observation of the elimination of cercariae for a three-month period and the calculation of mortality and infection rates, in control and in infected snails. The number of amoebocytes, granulocytes and hyalinocytes in the circulating hemolymph during different periods of infection was analyzed. The evolution of the infection in the tissues was observed by means of histological cross-sections. The melanic variant showed greater susceptibility to infection and a higher mortality rate. The albino variant showed a higher number of circulating amoebocytes, both granulocytes and hyalinocytes. A higher number of degenerated sporocysts were seen in the histological cross-sections of the albino variant. The results suggest that the melanic variant of B. glabrata was more susceptible to infection by S. mansoni than was the albino variant.Foi estudado comparativamente o comportamento das variantes albina e melânica de Biomphalaria glabrata de Belo Horizonte (MG. Brasil), em relação à susceptibilidade à infecção pelo Schistosoma mansoni de mesma origem, através da observação da eliminação de cercárias por um período de três meses e a verificação das taxas de mortalidade e infecção nos moluscos controles e infectados. Analisou-se também, o número de amebócitos granulócitos e hialinócitos na hemolinfa circulante em diferentes períodos de infecção. A evolução da infecção nos tecidos foi observada através de cortes histológicos. A variante melânica apresentou maior susceptibilidade à infecção e maior taxa de mortalidade. A variante albina apresentou maior número de amebócitos circulantes, tanto granulócitos quanto hialinócitos. Nos cortes histológicos foi verificado maior número de esporocistos degenerados na variedade albina. Por estes resultados sugere-se que nas populações estudadas a variante melânica de B. glabrata, foi mais susceptível à infecção pelo S. mansoni.21722