Water fragmentation by bare and dressed light ions with MeV energies: Fragment-ion-energy and time-of-flight distributions

The energy and time-of-flight distributions of water ionic fragments produced by impact of fast atoms and bare and dressed ions; namely, H+, Li0-3+, C1+, and C2+ are reported in this work. Fragment species as a function of emission energy and time-of-flight were recorded by using an electrostatic spectrometer and a time-of-flight mass spectrometer, respectively. An improved Coulomb explosion model coupled to a classical trajectory Monte Carlo (CTMC) simulation gave the energy centroids of the fragments for the dissociation channels resulting from the removal of two to five electrons from the water molecule. For the energy distribution ranging up to 50 eV, both the experiment and model reveal an isotropic production of multiple charged oxygen ions, as well as hydrogen ions. From the ion energy distribution, relative yields of the dissociation resulting from multiple ionization were obtained as a function of the charge state, as well as for several projectile energies. Multiple-ionization yields with charge state up to 4+, were extracted from the measurements of the time-of-flight spectra, focused on the production of single and multiple charged oxygen ions. The measurements were compared to ion-water collision experiments investigated at the keV energy range available in the literature, revealing differences and similarities in the fragment-ion energy distribution.Fil: Wolff, W.. Universidade Federal do Rio de Janeiro; BrasilFil: Luna, H.. Universidade Federal do Rio de Janeiro; BrasilFil: Schuch, R.. Alba Nova University Center; SueciaFil: Cariatore, Nelson Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; ArgentinaFil: Otranto, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; ArgentinaFil: Turco, Federico. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Fregenal, Daniel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Bernardi, Guillermo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Suárez, S.. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentin

The Ebro Delta: live hall for environmental education and coastal hazards analysis.

El Delta del Ebro es un delta con un dominio mixto, fluvial y del oleaje, cuya dinámica natural y tendencia evolutiva están siendo afectadas por la escasez de sedimentos aportados por el río debido a la regulación hidrológica de su cuenca. La falta de sedimentos está favoreciendo el hundimiento progresivo de la llanura deltaica, la erosión y el retroceso de su línea de costa. Las modificaciones dinámicas que puedan derivarse del cambio climático y la subida del nivel del mar agravarían la situación en que se encuentra el delta y la mitad de su superficie podría desaparecer a lo largo de este siglo. Colonizado por el hombre desde finales del siglo XIX, actualmente una comunidad de 50.000 personas depende de su explotación, y parte de ella vive sobre la propia llanura. Consciente del riesgo en que se encuentra, la población lucha por mitigarlo y convertir el delta en ejemplo de Desarrollo Sostenible. Estas características hacen del Delta del Ebro un lugar idóneo para comprender conceptos relacionados con el análisis de peligrosidad y riesgos y la gestión medioambiental. Este trabajo es la descripción de la realización y los resultados de una experiencia docente que realizamos en la Universidad Complutense de Madrid con alumnos de la Licenciatura en Geología en el Delta del Ebro. Con ella pretendemos contribuir a su formación científica y técnica, así como a la construcción de la ciudadanía del siglo XXI, incentivando un compromiso coherente con la conservación del Medio Natural y el Patrimonio Geológico. La experiencia nos reafirma en la posición de que la educación es una ineludible medida para la mitigación del riesgo y la conservación del Medio Natural.The Ebro Delta is a deltaic depositional systems controlled by river and wave processes, whose natural dynamics and evolutionary tendency are being affected by severe scarcity of sediments supplied by the river due to regulation of its basin. Sediment lack is enhancing subsidence of the deltaic plain, erosion and landwards movement of the coastline. This situation might be worsened by dynamic modifications derived of climate change such as sea level rise, and half of the subaerial delta might disappear throughout this century. The delta has been occupied since the end of the XIX century and currently 50.000 people depend on exploitation of delta resources. Even more, part of that population inhabit the deltaic plain. Population is aware of hazards that threaten them and daily struggles to transform the Ebro Delta into a paradigm of Sustainable Development. Given all those features this delta is an ideal place to understand concepts related to hazard analysis and environmental management. This work describes the development and results of an educational experience designed for undergraduate students of Geology of the Universidad Complutense de Madrid. This experience aims to contribute to the technical and scientific education of the students, as well as to the construction of the citizenship of the XXI century by means of promoting a consistent commitment to preservation of natural environments and geological heritage. This experience do also shows that education is an unavoidable measure to prevent hazards and preserve Nature.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEpu

Colisiones ión-átomo: una oportunidad para estudiar fenómenos dinámicos complejos

La colisión de iones con átomos es un problema que data de la época de Rutherford. En las últimas décadas, la creciente sofisticación en técnicas experimentales ha permitido observar detalles que antes eran impensables, midiendo simultáneamente varias partículas y encontrando sus correlaciones. También nos encontramos con evidencias que son, en muchos casos, muy difíciles de analizar teóricamente, y a veces, difíciles de comparar con ideas previas. En este artículo se plantea el problema básico y se resumen algunos experimentos recientes.Ion-atom collisions is a subject investigated from Ruthetford's time. In the last decades, due to the accelerated advance in experimental techniques, coincidence measurements have allowed to study the problem with great detail. Lately, the experimental evidence is often very complex to be analysed theoretically, and in some cases, difficult to match with previous ideas. In the present paper the basic problema and ame recent experiments are summarised

Unidentified transitions in one-photon intrashell dynamics in Rydberg atoms

One-photon intrashell transitions in strongly driven Li (n = 25) atoms are studied experimentally. Thedegeneracy of the n shell is lifted by orthogonal dc electric and magnetic fields, which also define the eccentricity of the initial coherent elliptic state. The transitions are driven by a radio frequency pulse linearly polarized parallel to the major axis of the ellipse. A small dc electric field component parallel to the magnetic field splits the one-photon resonance into two, and transitions in between are studied by state-selective field ionization. Unexpected lines in the ionization spectra relating to unknown transitions are found and discussed.Fil: Preclíková, J.. University of Bergen; NoruegaFil: Waheed, A.. University of Bergen; NoruegaFil: Fregenal, Daniel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Frette, Ø.. University of Bergen; NoruegaFil: Hamre, B.. University of Bergen; NoruegaFil: Hjertaker, B.T.. University of Bergen; NoruegaFil: Horsdal, E.. University Aarhus; DinamarcaFil: Pilskog, I.. University of Bergen; NoruegaFil: Førre, M.. University of Bergen; Norueg

Excitation of Rydberg wave packets with chirped laser pulses

We study Rydberg wave packets produced by pairs of time separated femtosecond laser pulses. The time separation ranges from femtosecond to picosecond time scales. The wave packets consist predominantly of f states of principal quantum numbers n = 22-32 in Li. With a direct analysis of the field ionization spectra the n-level-resolved classical orbit times are displayed. By chirping the second excitation pulse we demonstrate controlled amplitude oscillations of n-level amplitudes on femtosecond time scales.Fil: Preclíková, J.. University of Bergen; NoruegaFil: Kozák, M.. Karlova Univerzita; República ChecaFil: Fregenal, Daniel Eduardo. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Frette, Ø.. University of Bergen; NoruegaFil: Hamre, B.. University of Bergen; NoruegaFil: Hjertaker, B. T.. University of Bergen; NoruegaFil: Hansen, J. P.. University of Bergen; NoruegaFil: Kocbach, L.. University of Bergen; Norueg

Donezella-chaetetid mounds in the Valdeteja Formation (Bashkirian, Pennsylvanian) at Truébano, Cantabrian Mountains, northern Spain

The Bashkirian-lower Moscovian Valdeteja Formation crops out in the Cantabrian Zone (NW Spain). It is composed of pale grey limestone with a diverse fossil content, calcareous breccias and massive limestone composed of algal and microbial mounds accumulated in a high relief carbonate platform. Outstanding outcrops of that formation appear near the village of Truébano (León Province, North Spain) at the old coal mine “Mina Rosario.” The mine is a peculiarity in the formation as it shows interbedded siltstones and coal beds containing coal balls. The studied succession above the coal seam is lower Bashkirian and 20.2 m thick. Dark grey, massive to wellbedded limestones interbedded with thin marly beds are dominant in that interval. The main component of the limestones is the algospongia Donezella that is found in two different facies: packstone of resedimented Donezella, which appears in the lower beds of the section, and boundstone of Donezella, Girvanella and chaetetids, in the upper beds. Additional components are highly diverse including foraminifera, other calcified microbes, rhodophyta, sponges, echinoderms, arthropods, brachiopods, bryozoans and scarce corals and molluscs. Organic matter is abundant in the marly beds, but palynomorphs are poorly preserved. An interbedded layer of quartz sandstones lacking fossil content occurs in the upper part of the sequence. The depositional environment of the facies is part of a carbonate platform top near the fair-weather wave base, within subtidal zone, with development of “algal” mounds and sedimentation of debris from the same buildups. The composition and components distribution of both microfacies fit well with the mounds previously described in other outcrops of the Valdeteja Formation, with the exception of the participationof chaetetids as a main building component in some beds

Contornitas calcáreas en el Cretácico terminal de Caravaca (Dominio Subbético). Implicaciones paleogeográficas

This paper focuses on the deep marine carbonates of late Campanian to lower Maastricht!an age that crop out in the Subbetic Zone near Caravaca (Murcia province). Their sedimentological analysis allows to recognize a thick succession of dm-scale levels of calcareous "grainy" contourites alternating with fine-grained pelagites/hemipelagites. Those contourites, characterized by the abundance and variety of traction structures (horizontal and low angle bedding; cross-bedding, mud offshots, flaser bedding) together with other diagnostic features as internal erosive surfaces, inverse and normal grading at various scales, erosive bases, sharp top contacts), are interpreted as produced by bottom currents that were particularly intense during that time in the Betic basin, probably as a consequence of the onset of the contraction in the Mesozoic basins of Iberia. The Alpine convergence caused the closure in the latest Cretaceous of most former seaways (Pyrenean and Iberian basins) between the Atlantic and the Tethys oceans, and induced the progressive narrowing of the remaining seaway between Africa and Iberia

Electron emission in collisions between dressed Alq+ ions with He targets

Experimental and theoretical results are presented for electron emission in collisions between dressed Alq+ ions and atomic He targets. The experimental data are compared with a four-body CTMC model and two distorted wave models, namely the CDW and CDW-EIS. The contribution to total electron emission spectra from the ionisation of each collision center and as well as the simultaneous ionisation can be assessed separately.Fil: Monti, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Física de Rosario (i); ArgentinaFil: Fiol, Juan. Comisiã³n Nacional de Energã­a Atã³mica. Gerencia del Area Investigaciã³n y Aplicaciones No Nucleares. Gerencia de Fã­sica (centro Atã³mico Balseiro). Divisiã³n Colisiones Atã³micas; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); ArgentinaFil: Fregenal, Daniel Eduardo. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); ArgentinaFil: Fainstein, Pablo Daniel. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); ArgentinaFil: Rivarola, Roberto Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Física de Rosario (i); ArgentinaFil: Wolff, W.. Universidade Federal do Rio de Janeiro; BrasilFil: E. Horsdal. University Aarhus; DinamarcaFil: Bernardi, Guillermo Carlos. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); ArgentinaFil: Suarez, Sergio Gabriel. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentin

Broader conceptualization of remission assessed by the remission from depression questionnaire and its association with symptomatic remission: a prospective, multicenter, observational study

Abstract Background Goals of treating major depressive disorder (MDD) include achieving remission and avoiding relapse. It is possible that patients may have a broader view of remission than what is captured via clinician-rated scales. This patient perspective may, in turn, have an impact on treatment outcomes. Methods The association between a broader conceptualization of remission, based on the Remission from Depression Questionnaire (RDQ) score at baseline, and being in symptomatic remission after 6 months was evaluated in subjects (N = 613) with MDD in symptomatic remission at baseline (17-item Hamilton Rating Scale for Depression [HAMD-17] ≤7). Specific aspects of depression were assessed from physician and patient perspectives as secondary endpoints. A backwards selection strategy was used to statistically model remission status and determine association of factors with potential to influence remission. Results At month 6, after adjustment for baseline HAMD-17 score, there was no association between baseline RDQ score and symptomatic remission status (HAMD-17), relapse, composite remission status, healthcare resource utilization, or quality of life. There was no association between functional impairment scores at baseline (Sheehan Disability Scale and Social and Occupational Functioning Assessment Scale) and symptomatic remission status (HAMD-17) at month 6. Conclusions This study indicates that RDQ-constructs are independent from symptomatic remission. Symptom severity at study entry appeared to be the only significant predictor of eventual relapse during the 6-month follow-up period. However, our results also suggest that the current definition of remission that is based on symptom reduction should be further elaborated and that alternative or additional definitions should be considered in determining remission