Search results for "oio"
showing 10 items of 152 documents
Il Corridioio Meridiano come dispositivo territoriale per la competitività del Mezzogiorno
2008
Una nuova vision ha animato la redazione del Quadro Strategico Nazionale 2007-13 per il settore delle “infrastrutture e città”: una strategia reticolare di innovazione capace di orientare interventi di costituzione di cluster produttivi e innovativi, di connessione di piattaforme, di ricentralizzazione di aree urbane attraverso la riqualificazione dei nodi e la dotazione di servizi collettivi. La strategia mira soprattutto alla ridefinizione di funzioni di rango metropolitano in grado di potenziare il ruolo di Global Gateways che le città stanno progressivamente assumendo all'interno dei processi più avanzati di rigenerazione urbana e competitività territoriale, capaci di agire da “trasform…
Resonance ionization mass spectroscopy for trace analysis of neptunium
1993
Resonance ionization mass spectroscopic (RIMS) measurements for trace analysis and spectroscopy of 237Np, the ecologically most important isotope of neptunium, are described. The chemical procedure for the separation of neptunium from aqueous samples as well as the preparation of filaments for RIMS are outlined. Several two- and three-step excitation schemes have been investigated in order to find suitable conditions for the sensitive detection of 237Np. Using a three-step, three-color excitation and ionization scheme an overall detection efficiency of 3×10−8 was obtained, resulting in a detection limit of 4×108 atoms (160 fg) of 237Np. The hyperfine structure splittings of the levels under…
Resonant Photoelectron Diffraction
2013
A layout of a resonant photoelectron diffraction, RESPED, experiment is described from the theoretical basis to the data acquisition and analysis procedures. The theory of the resonance between the directly emitted photoelectron of a selected valence band and the electron emitted by autoionization (Auger) of the same valence band is presented within a formal frame. The critical issue of the angular symmetry and distribution of the resonating electron is discussed in connection with the current computational protocols for photoelectron diffraction, PED, analysis. A few representative applications are presented, where RESPED is shown to overcome some limitations of conventional PED thanks to …
Laser resonant ionization of plutonium
1985
Resonance ionization mass spectrometry (RIMS) has been tested for the isotope-selective determination of trace amounts of plutonium. An atomic beam is formed by evaporating plutonium atoms from a rhenium-filament heated to 1800 °C. The radiation of a pulsed dye laser excites the atoms in a two-photon process (λ=595.2 nm) followed by photoionization of the excited atoms. Mass selectivity is obtained by use of a time-of-flight spectrometer. A resonant signal of239Pu was measured with 1013 atoms deposited on the filament.
Analytical evaluation of integrals occurring in bound-free transitions.
1988
A class of three-dimensional integrals on spatial coordinates of the type occurring in treatments of multiphoton ionization of atoms and of other bound-free transitions is evaluated in closed form for both hydrogenic and Slater-type wave functions. The reported method of evaluation is illustrated with a number of examples, including the multiphoton ionization of hydrogen by a very intense laser field, when the ejected electrons have absorbed more photons than the minimum required to reach the continuum.
Strong-field molecular ionization: determination of ionization probabilities calibrated with field-free alignment
2006
International audience; We report an original optical method providing the probability of molecular ionization induced by femtosecond laser pulses. The approach consists of exploiting molecular alignment in order to extract reliable information about ionization. The cross defocusing technique implemented for this purpose reveals a sensitivity with respect to post-pulse alignment, as well as to free electron density induced by the ultra-short laser pulse. The analysis of the resulting signal gives thus access to absolute single-ionization probabilities calibrated through the degree of alignment provided that free electrons are mainly produced from single-ionization. The relevance of the meth…
Family burden, social support and community health in caregivers of people with serious mental disorder
2018
RESUMEN Objetivo Identificar el nivel de sobrecarga de los cuidadores y analizar los factores asociados con el cuidado familiar en salud mental. Método Se realizó un estudio descriptivo transversal realizado entre los meses de enero y julio del año 2016, en el que se evalúa una muestra de cuidadores de siete dispositivos públicos y una asociación de familiares y pacientes identificando la sobrecarga de los mismos y los factores que contribuyen a reducir estos niveles, a través del instrumento Zarit Burden Inventor y . El estudio se llevó a cabo de acuerdo a las recomendaciones de los comités de ética de las instituciones participantes. Resultados Participaron 107 cuidadores. Las principales…
Nitric oxide-active compounds modulate glutamatergic and GABAergic transmission in globus pallidus of rat
2011
The globus pallidus (GP) of rodents, homologous to the external globus pallidus of primates, plays a critical role in the expression of basal ganglia (BG) function. Glutamatergic and GABAergic inputs have been demonstrated to greatly modulate the spontaneous GP activity. In this study the effects of local applied NO-active compounds on glutamate (GLU)- and GABA-evoked responses were investigated in rat GP neurons. Extracellularly recorded single units from anesthetized rats were treated with GLU or GABA before and during the microiontophoretic application of S-nitrosoglutathione (SNOG), a NO donor, and Nω-nitro-L-arginine methyl ester (L-NAME), a NOS inhibitor. Most GP cells were excited by…
Nitric oxide-active compounds modulate the intensity of glutamate-evoked responses in the globus pallidus
2011
In this study, the effects of microiontophoretically applied NO-active compounds on glutamate(GLU)-evoked responses were investigated in globus pallidus (GP) neurons from anesthetized rats. Most GP cells were excited by S-nitrosoglutathione (SNOG), an NO donor, whereas administration of Nω-nitro-L-arginine methyl ester (L-NAME), a NOS inhibitor, induced a decrease of GP neurons activity. Nearly all neurons responding to SNOG and/or L-NAME showed significant excitatory responses to the administration of iontophoretic GLU. In these cells, the changes induced by NO-active drugs in the magnitude of GLU-evoked responses were used as indicators of NO modulation. When an NO-active drug and GLU wer…
Modelling Photoionisations in Tautomeric DNA Nucleobase Derivatives 7H-Adenine and 7H-Guanine: Ultrafast Decay and Photostability
2021
The study of radiation effects in DNA is a multidisciplinary endeavour, connecting the physical, chemical and biological sciences. Despite being mostly filtered by the ozone layer, sunlight radiation is still expected to (photo)ionise DNA in sizeable yields, triggering an electron removal process and the formation of potentially reactive cationic species. In this manuscript, photoionisation decay channels of important DNA tautomeric derivatives, 7H-adenine and 7H-guanine, are characterised with accurate CASSCF/XMS-CASPT2 theoretical methods. These simulation techniques place the onset of ionisation for 7H-adenine and 7H-guanine on average at 8.98 and 8.43 eV, in line with recorded experimen…