Toward a test of angular momentum coherence in a twin-atom interferometer

We present a scheme well-suited to investigate quantitatively the angular momentum coherence of molecular fragments. Assuming that the dissociated molecule has a null total angular momentum, we investigate the propagation of the corresponding atomic fragments in the apparatus. We show that the envisioned interferometer enables one to distinguish unambiguously a spin-coherent from a spin-incoherent dissociation, as well as to estimate the purity of the angular momentum density matrix associated with the fragments. This setup, which may be seen as an atomic analogue of a twin-photon interferometer, can be used to investigate the suitability of molecule dissociation processes -- such as the metastable hydrogen atoms H($2^2 S$)-H($2^2 S$) dissociation - for coherent twin-atom optics.Comment: 6 pages, 3 Figures. Final version accepted for publication in Europhysics Letter

Water issues in Hawaii: public attitudes in 2004 and 2010

This report examines Hawai‘i residents' awareness of, attitudes about, and actions taken concerning water quality. "Water quality" is a measure of the suitability of water for a particular use, such as drinking, recreation, agricultural irrigation, or protection and maintenance of aquatic life

Peculiar Broad Absorption Line Quasars found in DPOSS

With the recent release of large (i.e., > hundred million objects), well-calibrated photometric surveys, such as DPOSS, 2MASS, and SDSS, spectroscopic identification of important targets is no longer a simple issue. In order to enhance the returns from a spectroscopic survey, candidate sources are often preferentially selected to be of interest, such as brown dwarfs or high redshift quasars. This approach, while useful for targeted projects, risks missing new or unusual species. We have, as a result, taken the alternative path of spectroscopically identifying interesting sources with the sole criterion being that they are in low density areas of the g - r and r - i color-space defined by the DPOSS survey. In this paper, we present three peculiar broad absorption line quasars that were discovered during this spectroscopic survey, demonstrating the efficacy of this approach. PSS J0052+2405 is an Iron LoBAL quasar at a redshift z = 2.4512 with very broad absorption from many species. PSS J0141+3334 is a reddened LoBAL quasar at z = 3.005 with no obvious emission lines. PSS J1537+1227 is a Iron LoBAL at a redshift of z = 1.212 with strong narrow Mgii and Feii emission. Follow-up high resolution spectroscopy of these three quasars promises to improve our understanding of BAL quasars. The sensitivity of particular parameter spaces, in this case a two-color space, to the redshift of these three sources is dramatic, raising questions about traditional techniques of defining quasar populations for statistical analysis.Comment: 27 pages, 13 figures, Accepted to the Astronomical Journa

The Liverpool Telescope: Rapid follow-up observation of Targets of opportunity with a 2 m robotic telescope

The Liverpool Telescope, situated at Roque de los Muchachos Observatory, La Palma, Canaries, is the first 2-m, fully instrumented robotic telescope. It recently began observations. Among Liverpool Telescope's primary scientific goals is to monitor variable objects on all timescales from seconds to years. An additional benefit of its robotic operation is rapid reaction to unpredictable phenomena and their systematic follow up, simultaneous or coordinated with other facilities. The Target of Opportunity Programme of the Liverpool Telescope includes the prompt search for and observation of GRB and XRF counterparts. A special over-ride mode implemented for GRB/XRF follow-up enables observations commencing less than a minute after the alert, including optical and near infrared imaging and spectroscopy. In particular, the moderate aperture and rapid automated response make the Liverpool Telescope excellently suited to help solving the mystery of optically dark GRBs and for the investigation of currently unstudied short bursts and XRFs.Comment: 4 pages, 1 figure. To appear in the Proceedings of The Restless High-Energy Universe, 5-8 May 2003, Amsterdam, E.P.J. van den Heuvel, J.J.M. in 't Zand, and R.A.M.J. Wijers (eds.

Proceso de enseñanza-aprendizaje en asignaturas de investigación para el desarrollo de tesis de los egresados de la escuela de ingeniería mecatrónica en la Universidad Ricardo Palma

Este artículo se enfoca en describir y explicar que el proceso de enseñanza-aprendizaje en las materias de investigación del Plan de Estudios 2008-II de la Escuela Profesional de Ingeniería Mecatrónica aportan las competencias para que el graduado tenga las herramientas en el desarrollo de su Tesis y obtener el Título Profesional en Ingeniería Mecatrónica, tal es así que se encontró altas tasas de graduados ya titulados bajo la modalidad de Tesis, sin embargo, también se encontró un regular porcentaje de graduados que aún no se titulan. Para mejorar este porcentaje de no titulados, se ha implementado el Programa de Titulación por Tesis, que, como parte de su estructura, considera metodologías y estrategias que ayudan a desarrollar competencias de investigación en el graduado, cuyos resultados de la aplicación ha permitido mejorar desde 8% a 13% los niveles de elaboración de Tesis para obtener el título profesional. &nbsp

Point-of-care assessment of platelet reactivity in the emergency department may facilitate rapid rule-out of acute coronary syndromes: a prospective cohort pilot feasibility study

Objective: Accurate, efficient and cost-effective disposition of patients presenting to emergency departments (EDs) with symptoms suggestive of acute coronary syndromes (ACS) is a growing priority. Platelet activation is an early feature in the pathogenesis of ACS; thus, we sought to obtain an insight into whether point-of-care testing of platelet function: (1) may assist in the rule-out of ACS; (2) may provide additional predictive value in identifying patients with non-cardiac symptoms versus ACS-positive patients and (3) is logistically feasible in the ED. Design: Prospective cohort feasibility study. Setting: Two urban tertiary care sites, one located in the USA and the second in Argentina. Participants: 509 adult patients presenting with symptoms of ACS. Main outcome measures Platelet reactivity was quantified using the Platelet Function Analyzer-100, with closure time (seconds required for blood, aspirated under high shear, to occlude a 150 µm aperture) serving as the primary endpoint. Closure times were categorised as ‘normal’ or ‘prolonged’, defined objectively as the 90th centile of the distribution for all participants enrolled in the study. Diagnosis of ACS was made using the standard criteria. The use of antiplatelet agents was not an exclusion criterion. Results: Closure times for the study population ranged from 47 to 300 s, with a 90th centile value of 138 s. The proportion of patients with closure times ≥138 s was significantly higher in patients with non-cardiac symptoms (41/330; 12.4%) versus the ACS-positive cohort (2/105 (1.9%); p=0.0006). The specificity of ‘prolonged’ closure times (≥138 s) for a diagnosis of non-cardiac symptoms was 98.1%, with a positive predictive value of 95.4%. Multivariate analysis revealed that the closure time provided incremental, independent predictive value in the rule-out of ACS. Conclusions: Point-of-care assessment of platelet reactivity is feasible in the ED and may facilitate the rapid rule-out of ACS in patients with prolonged closure times

Peculiar Broad Absorption Line Quasars Found in The Digitized Palomar Observatory Sky Survey

With the recent release of large (i.e., ≳100 million objects), well-calibrated photometric surveys, such as Digitized Palomar Observatory Sky Survey (DPOSS), Two Micron All Sky Survey, and Sloan Digital Sky Survey, spectroscopic identification of important targets is no longer a simple issue. In order to enhance the returns from a spectroscopic survey, candidate sources are often preferentially selected to be of interest, such as brown dwarfs or high-redshift quasars. This approach, while useful for targeted projects, risks missing new or unusual species. We have, as a result, taken the alternative path of spectroscopically identifying interesting sources with the sole criterion being that they are in low-density areas of the g-r and r-i color space defined by DPOSS. In this paper, we present three peculiar broad absorption line quasars that were discovered during this spectroscopic survey, demonstrating the efficacy of this approach. PSS J0052+2405 is an iron low-ionization broad absorption line (LoBAL) quasar at a redshift z = 2.4512 ± 0.0001 with very broad absorption from many species. PSS J0141+3334 is a reddened LoBAL quasar at z = 3.005 ± 0.005 with no obvious emission lines. PSS J1537+1227 is an iron LoBAL at a redshift of z = 1.212 ± 0.007 with strong narrow Mg II and Fe II emission. Follow-up high-resolution spectroscopy of these three quasars promises to improve our understanding of BAL quasars. The sensitivity of particular parameter spaces, in this case a two-color space, to the redshift of these three sources is dramatic, raising questions about traditional techniques of defining quasar populations for statistical analysis