1,994 research outputs found
Spitzer observations of Bow Shocks and Outflows in RCW 38
We report Spitzer observations of five newly identified bow shocks in the
massive star-forming region RCW 38. Four are visible at IRAC wavelengths, the
fifth is visible only at 24 microns. Chandra X-ray emission indicates that
winds from the central O5.5 binary, IRS~2, have caused an outflow to the NE and
SW of the central subcluster. The southern lobe of hot ionised gas is detected
in X-rays; shocked gas and heated dust from the shock-front are detected with
Spitzer at 4.5 and 24 microns. The northern outflow may have initiated the
present generation of star formation, based on the filamentary distribution of
the protostars in the central subcluster. Further, the bow-shock driving star,
YSO 129, is photo-evaporating a pillar of gas and dust. No point sources are
identified within this pillar at near- to mid-IR wavelengths.
We also report on IRAC 3.6 & 5.8 micron observations of the cluster
DBS2003-124, NE of RCW 38, where 33 candidate YSOs are identified. One star
associated with the cluster drives a parsec-scale jet. Two candidate HH objects
associated with the jet are visible at IRAC and MIPS wavelengths. The jet
extends over a distance of ~3 pc. Assuming a velocity of 100 km/s for the jet
material gives an age of about 30,000 years, indicating that the star (and
cluster) are likely to be very young, with a similar or possibly younger age
than RCW 38, and that star formation is ongoing in the extended RCW 38 region.Comment: 27 pages, 6 figures, accepted to Ap
Is the Doctor in? The Effects of Emigration on the Health Care Systems in Poland and Romania
The “brain drain” phenomenon encompasses the mass movement of highly educated individuals. Highly-skilled and well-educated migrants are moving to more developed and urban settings, often in search of a higher standard of living and better wages. Since joining the European Union and the Schengen Agreement, Poland and Romania have experienced significant emigration which has subsequently affected their health care systems. Motivations for emigrating from these two countries and the effects emigration has had on patients and other doctors will be considered. The paper also seeks to compare policy responses to the mass medical emigration phenomenon in both countries, as well as the outcomes of such policies. The main methodology of study throughout this project entails a comparative assessment of the governmental policy responses to brain drain. An analysis of Poland’s and Romania’s health care systems will be performed initially.
The analysis includes details on the causes and factors that bring about migration, the impact that emigration has had on patients, how doctors remaining in the sending country are affected, and what social upheavals and unrest result from such emigration. Following, the levels and flows of migration are considered for each country, looking at the type of people leaving, whether educated or not, and the range of professions, with a focus on health professionals that are migrating from both countries. After an analysis has been performed for both countries, the results will be compared to one another, paying special attention to any differences and potential reasons for these differences
The construction of a social studies vocabulary test for teachers in training.
Thesis (Ed.M.)--Boston Universit
The Structure of the Star-forming Cluster RCW 38
We present a study of the structure of the high mass star-forming region
RCW~38 and the spatial distribution of its young stellar population. Spitzer
IRAC photometry 3-8um are combined with 2MASS near-IR data to identify young
stellar objects by IR-excess emission from their circumstellar material.
Chandra X-ray data are used to identify class III pre-main sequence stars
lacking circumstellar material. We identify 624 YSOs: 23 class 0/I and 90 flat
spectrum protostars, 437 Class II stars, and 74 Class III stars. We also
identify 29 (27 new) O star candidates over the IRAC field. Seventy-two stars
exhibit IR-variability, including seven class 0/I and 12 flat spectrum YSOs. A
further 177 tentative candidates are identified by their location in the IRAC
[3.6] vs. [3.6]-[5.8] cmd. We find strong evidence of subclustering in the
region. Three subclusters were identified surrounding the central cluster, with
massive and variable stars in each subcluster. The central region shows
evidence of distinct spatial distributions of the protostars and pre-main
sequence stars. A previously detected IR cluster, DB2001_Obj36, has been
established as a subcluster of RCW 38. This suggests that star formation in RCW
38 occurs over a more extended area than previously thought. The gas to dust
ratio is examined using the X-ray derived hydrogen column density, N_H and the
K-band extinction, and found to be consistent with the diffuse ISM, in contrast
with Serpens & NGC1333. We posit that the high photoionising flux of massive
stars in RCW 38 affects the agglomeration of the dust grains.Comment: 98 pages, 15 figure
Differential Perception And Adolescent Drinking In The United States: Preliminary Considerations
This paper addresses adolescent drinking from a perspective very similar to Sutherland\u27s differential association theory. Drinking occurs when positive perceptions of drinking outweigh or outnumber negative ones. Our research focuses on images of drinking communicated by rationalized sources organized specifically to shape perceptions of drinking. We call these organizations agencies and assess their impact on perceptions of drinking. It is our contention that the political economic context of the United States in which these agencies function is such that positive images of drinking outnumber and outweigh negative ones, and that this is an important factor contributing to adolescent drinking
High recovery of nitrogenase activity and of 55Fe-labeled nitrogenase in heterocysts isolated from Anabaena variabilis
Multi-color pyrometer for materials processing in space
The design, construction and calibration of a computer-linked multicolor pyrometer is described. The device was constructed for ready adaptation to a spacecraft and for use in the control of thermal processes for manufacturing materials in space. The pyrometer actually uses only one color at a time, and is relatively insensitive to uncertainties in the heated object's emissivity because the product of the color and the temperature has been selected to be within a regime where the radiant energy emitted from the body increases very rapidly with temperature. The instrument was calibrated and shown to exceed its design goal of temperature measurements between 300 and 2000 C, and its accuracy in the face of imprecise knowledge of the hot object's emissivity was demonstrated
Contextual Influences and Strategies for Dissemination and Implementation in Mental Health
Implementation science has emerged to bridge the gap between research and practice. A number of conceptual frameworks have been developed to advance implementation research and illuminate the contextual influences that can facilitate or impede the implementation of evidence-based practices. Contextual factors that may be important in the dissemination and implementation of evidence-based practice may occur at the system-, organizational-, and provider-levels. System-level barriers may include external policies, incentives, and peer pressure. Organizational-level factors that are important in implementation include organizational culture and climate and implementation climate. At the individual provider-level, barriers may occur around provider attitudes, knowledge, and self-efficacy. Finally, additional barriers such as client-level that can be used to overcome contextual barriers when attempting to implement evidence-based practices into new settings. Several exemplar implementation strategies are discussed, including the Availability, Responsiveness, and Continuity intervention, Community Development Team model, and Interagency Collaborative Team Model
The lack of the right to be heard in the Act on Mutual Recognition and Enforcement of Detention en Conditional Sanctions.
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