Teaching the patient with myocardial infarction

Thesis (M.S.)--Boston Universit

A Constraint Programming Approach to the Hospitals / Residents Problem

An instance I of the Hospitals / Residents problem (HR) involves a set of residents (graduating medical students) and a set of hospitals, where each hospital has a given capacity. The residents have preferences for the hospitals, as do hospitals for residents. A solution of I is a stable matching, which is an assignment of residents to hospitals that respects the capacity conditions and preference lists in a precise way. In this paper we present constraint encodings for HR that give rise to important structural properties. We also present a computational study using both randomly-generated and real-world instances. Our study suggests that Constraint Programming is indeed an applicable technology for solving this problem, in terms of both theory and practice

A meta analysis of effectiveness of E interventions to reduce alcohol consumption in college and university students

Objective: To evaluate the effectiveness and moderators of E-Interventions versus assessment only (AO) controls in the reduction of alcoholic drinks per week (DPW) in university students. Study design and methods: Cochrane library, CINAEL, ERIC, MEDLINE, PsycINFO, PubMed, and Web of Science were searched up to June 2017. Studies were included if they were: an RCT, assessed the effectiveness of E-Interventions at reducing DPW, and employed university/college students. 23 studies (N = 7,614) were included and quality was assessed using the JADAD scale. Results: Weighted mean effect sizes were calculated using random-effects models. These showed a small, significant effect of E-Interventions at reducing the number of alcoholic DPW. Moderator analysis found a significant advantage for web-based personalised feedback interventions compared to other E-Interventions. Conclusions: E-Interventions show a small, significant effect at reducing mean alcoholic DPW. Personalised feedback E-Interventions showed the strongest effect

Photometry and spectroscopy in the open cluster Alpha Persei, 2

Results from a combination of new spectroscopic and photometric observations in the lower main-sequence and pre-main sequence of the open cluster alpha Persei are presented. New echelle spectroscopy has provided radial and rotational velocity information for thirteen candidate members, three of which are nonmembers based on radial velocity, absence of a Li 6707A feature, and absence of H-alpha emission. A set of revised rotational velocity estimates for several slowly rotating candidates identified earlier is given, yielding rotational velocities as low as 7 km/s for two apparent cluster members. VRI photometry for several pre-main sequence members is given; the new (V,V-I(sub K)) photometry yields a more clearly defined pre-main sequence. A list of approximately 43 new faint candidate members based on the (V,V-I(sub K)) CCD photometry is presented in an effort to identify additional cluster members at very low masses. Low-dispersion spectra obtained for several of these candidates provide in some cases supporting evidence for cluster membership. The single brown dwarf candidate in this cluster is for the first time placed in a color-magnitude diagram with other cluster members, providing a better means for establishing its true status. Stars from among the list of new photometric candidates may provide the means for establishing a sequence of cluster members down to very faint magnitudes (V approximately 21) and consequently very low masses. New coordinate determinations for previous candidate members and finding charts for the new photometric candidates are provided in appendices

A Visit to West Point

"The name of West Point is dear to the heart of every patriotic American citizen…

Generalized Arago-Fresnel laws: The EME-flow-line description

We study experimentally and theoretically the influence of light polarization on the interference patterns behind a diffracting grating. Different states of polarization and configurations are been considered. The experiments are analyzed in terms of electromagnetic energy (EME) flow lines, which can be eventually identified with the paths followed by photons. This gives rise to a novel trajectory interpretation of the Arago-Fresnel laws for polarized light, which we compare with interpretations based on the concept of "which-way" (or "which-slit") information.Comment: 14 pages, 6 figure

X-Ray Activity in the Open Cluster IC 4665

We present the results of a joint ROSAT High Resolution Imager (HRI) and optical investigation of the open cluster IC 4665. The ROSAT data contains detections for 28 stellar sources in the field, including 22 cluster members and candidate members spanning the color range -0.18 less than or equal to (B - V(sub o)) less than or equal to +1.63 (approx. B3 - M3). Upper limits are given for the remaining members (or candidate members) in the HRI field. Keck HIRES spectra have been obtained that yield radial and rotational velocity measures, respectively, for faint, low mass candidate members located within the field of the ROSAT HRI observation. In addition, photometry of possible optical counterparts to previously uncatalogued X-ray sources in the HRI field is presented. The trends in X-ray properties with (B - V) color in IC 4665 are found to be quite similar to that for other, more nearby young clusters such as the Pleiades and alpha Persei. In particular, a maximum in normalized X-ray luminosity of log (L(sub x)/L(sub bol)) approx. equal 3 is observed, beginning in the color range of (B - V)(sub o) = 0.7 - 0.8. This is similar to the corresponding color range among Pleiades members, in agreement with the earlier estimate, that the age of IC 4665 is similar to the age of the Pleiades. The correlation of rotation and X-ray emission levels is consistent with that in other young clusters. Among the high mass stars in IC 4665, five B stars are detected as X-ray sources. Of these, one is a spectroscopic binary while the remaining objects are apparently single staxs. The level of intrinsic X-ray emission observed in the rapidly rotating (v sini greater than 200 km/ s), single B stars is consistent with an origin due to shock heating of the ambient medium by radiatively driven, rotationally enhanced winds. On the basis of these observations and the results for other clusters, we argue that observed levels of X-ray emission in high mass stars of log (L(sub x)/L(sub bol)) greater than -6.0 are likely due to intrinsic emission associated with the B stax itself rather than emission from a late-type secondary. Finally, our results suggest that the initial angular momentum distributions and the subsequent evolution of rotation, L(sub x), and (L(sub x)/L(sub bol)) occur in practically identical fashions in clusters with ages approx. less than 100 Myr