Search results for "COPI"
showing 10 items of 2618 documents
α-decay spectroscopy of the N = 130 isotones 218Ra and 220Th: Mitigation of α-particle energy summing with implanted nuclei
2019
An analysis technique has been developed in order to mitigate energy summing due to sequential short-lived α decays from nuclei implanted into a silicon detector. Using this technique, α-decay spectroscopy of the N=130 isotones 218Ra (Z=88) and 220Th (Z=90) has been performed. The energies of the α particles emitted in the 218Ra→214Rn and 220Th→216Ra ground-state-to-ground-state decays have been measured to be 8381(4) keV and 8818(13) keV, respectively. The half-lives of the ground states of 218Ra and 220Th have been measured to be 25.99(10) μs and 10.4(4) μs, respectively. The half-lives of the ground states of the α-decay daughters, 214Rn and 216Ra, have been measured to be 259(3) ns and …
Determination of β-decay ground state feeding of nuclei of importance for reactor applications
2020
In β-decay studies the determination of the decay probability to the ground state (g.s.) of the daughter nucleus often suffers from large systematic errors. The difficulty of the measurement is related to the absence of associated delayed γ-ray emission. In this work we revisit the 4πγ−β method proposed by Greenwood and collaborators in the 1990s, which has the potential to overcome some of the experimental difficulties. Our interest is driven by the need to determine accurately the β-intensity distributions of fission products that contribute significantly to the reactor decay heat and to the antineutrinos emitted by reactors. A number of such decays have large g.s. branches. The method is…
Coping strategies in life stories of young adults with foster care backgrounds
2021
Tutkimuksessa tarkasteltiin sijoitettuna olleiden nuorten aikuisten selviytymiskeinoja 18 yksilöhaastattelun avulla. Fenomenologisella analyysilla (IPA; Smith & Osborn, 2003. Interpretative phenomenological analysis. Teoksessa J. A. Smith (toim.), Qualitative Psychology (s. 51–80). Sage) tunnistettiin kolme pääteemaa liittyen selviytymiskeinoihin vastoinkäymisissä ja haasteissa: sisäänpäin suuntautuminen, ulospäin suuntautuminen sekä omiin elinolosuhteisiin vaikuttaminen. Lisäksi tunnistettiin keino, joka oli käytössä vain varhaisaikuisuudessa, hyväksyminen. Tulosten perusteella on tärkeää kuulla sijoitettuna olleita nuoria aikuisia koskien heidän selviytymiskeinojaan sekä lisätä sijaisperh…
Evaluación de las técnicas de obtención de muestra percutánea transtorácica de lesiones pulmonares y mediastínicas guiadas por Tomografía Computariza…
2023
Las técnicas empleadas para la obtención de muestras de lesiones torácicas, mediante Punción Aspiración con Aguja Fina (PAAF) y Biopsia con Aguja Gruesa (BAG), a partir de punciones percutáneas guiadas por exploraciones radiológicas (con Tomografía Computarizada (TC), fluoroscopia-TC o ecografía), tienen un papel destacado en tres escenarios clínicos concretos: 1) Manejo y diagnóstico del nódulo pulmonar: • Diferenciación benignidad vs malignidad, caracterización anatomopatológica +/- microbiológica. 2) Diagnóstico y estadificación del cáncer de pulmón: • Tipificación anatomopatológica e inmunohistoquímica, realización de estudios moleculares (basales y de resistencia a los tratamientos imp…
Medicina perioperatoria individualizada en cirugía oncológica
2021
Se define la Medicina perioperatoria como la asistencia integral, multidisciplinar y centrada en el paciente desde la indicación de un proceso quirúrgico hasta su recuperación completa. Estos tres conceptos permiten sinérgicamente obtener una asistencia de calidad y mejores resultados. El objetivo de esta tesis ha sido plasmar este nuevo modo de entender la atención médica perioperatoria a través varios proyectos de investigación. Se han agrupado en cuatro bloques principales: estrategia individualizada de neumoperitoneo, ventilación mecánica y bloqueo neuromuscular en cirugía laparoscópica, y la estrategia analgésica en cirugía oncológica. Bloque 1: Estrategia individualizada de neumoperit…
Sustainability Perspectives in Organizational and Workplace Learning Studies
2022
The association between sustainability and learning in organizations and workplaces represents a current articulated grand challenge for human resource development (HRD) and learning studies and practice, which calls for integrated inquiries. However, studies of learning in organizations and workplaces deal with sustainability in scattered and diverse ways that promote calls for more integrated understandings of the different approaches and associations. This article outlines the results from a scoping thematic review mapping out leading perspectives within the research fields of HRD, organizational learning (OL) and workplace learning (WPL). This article thus explores the perspectives that…
Alignment of linear molecules by short duration laser pulses
2005
Alignment of linear molecules is efficiently induced by strong linearly polarized laser pulses. In the case of short pulses with respect to molecular rotation, periodic alignment appears in field-free conditions after the extinction of the field. This manuscript presents three techniques where the value of allows to quantify alignment without molecular dissociation nor additional alignment. They use a weak time-delayed probe pulse which experiences the optical properties of an aligned sample and shows modification of its characteristics. The first of them measures a depolarization due to the birefringence of the sample. The second one is based on the defocusing produced by the spatial distr…
Ge quantum well plasmon-enhanced quantum confined Stark effect modulator
2014
ABSTRACTWe theoretically and experimentally investigate a novel modulation concept on silicon (Si) based on the combination of quantum confinement and plasmon enhancement effects. We experimentally study the suitability of Ge/SiGe quantum wells (QWs) on Si as the active material for a plasmon-enhanced optical modulator. We demonstrate that in QW structures absorption and modulation of light with transverse magnetic (TM) polarization are greatly enhanced due to favorable selection rules. Later, we theoretically study the plasmon propagation at the metal-Ge/SiGe QW interface. We design a novel Ge/SiGe QW structure that allows maximized overlap between the plasmonic mode and the underlying Ge/…
Unravelling the Intertwined Atomic and Bulk Nature of Localised Excitons by Attosecond Spectroscopy
2021
The electro-optical properties of most semiconductors and insulators of technological interest are dominated by the presence of electron-hole quasi-particles, called excitons. The manipulation of excitons in dielectrics has recently received great attention, with possible applications in different fields including optoelectronics and photonics. Here, we apply attosecond transient reflection spectroscopy in a sequential two-foci geometry and observe sub-femtosecond dynamics of a core-level exciton in bulk MgF2 single crystals. Furthermore, we access absolute phase delays, which allow for an unambiguous comparison with theoretical calculations. Our results show that excitons surprisingly exhi…
The Mediating Role of Individual Differences in the Interaction between Specific Socioprofessional Pressures and Job Satisfaction
2014
Abstract Previous research suggests that individual differences play an essential role in the complex process of organisational stress. The mediator role of specific individual differences and coping strategies, in the stressor – strain (effect) relationship is investigated in the present research. One sample of romanian employees (N=311) from an administrative-public service organisation participated in the study. Using the Pressure Managment Indicator (PMI, Williams & Cooper, 1998 ; PMI-RO, Brate, 2004, 2008 ), findings revealed significant mediating interactions between specific socioprofessional pressures and job satisfaction. The results have practical implications for the future resea…