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OBJECTIVE: Emergency medicine has been identified as the specialty that has gained the most young physicians who have changed their careers. To identify factors that may have contributed to such career changes, the authors compared the characteristics of three groups of physicians trained at their medical school: those who chose and stayed in emergency medicine, those who migrated into emergency medicine from other specialties, and those who moved out of emergency medicine. METHODS: A prospective longitudinal study was conducted. The sample consisted of physicians who chose emergency medicine as their careers at graduation and stayed in the specialty (n = 24), those who migrated from other specialties into emergency medicine (n = 51), and those who moved out of emergency medicine (n = 10). This sample was obtained from a total of 2,173 graduates of Jefferson Medical College between 1978 and 1987. The three groups of physicians were compared according to their academic performances both during medical school and after graduation. The dependent variables were freshmen and sophomore grade point averages (GPAs), written clinical examination scores, scores on National Board of Medical Examiners examination (Parts I, II, and III), and residency program directors' ratings. Age and indebtedness at medical school graduation and board certification status also were examined. RESULTS: Those physicians who stayed in emergency medicine and those who migrated from other specialties into emergency medicine had similar measures of academic performance, but both of these groups had higher academic performance measures and higher board certification rates than did the physicians who moved out of emergency medicine. Those who stayed in emergency medicine had the highest mean debt in the senior year of medical school. CONCLUSIONS: High academic performance and high indebtedness are factors associated with choosing or staying in the specialty of emergency medicine. 相似文献
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Abstract. Airborne geophysical reconnaissance was used to identify
potential flow paths for mercury-rich, acidic water entering
Clear Lake near the Sulphur Bank Mercury Mine. Airborne magnetic
and electromagnetic conductivity surveys were conducted over a
12.3 km2 (4.75
mi2) area that included the Oaks Arm
of Clear Lake and the old mine. These surveys identified four
magnetic and/or conductive anomalies that may represent
groundwater conduits towards or away from the Herman
Impoundment. An anomaly that extended from Herman Impoundment
through a waste rock dam and into Clear Lake was selected for a
more detailed ground electromagnetic conductivity survey. The
combined results of the airborne and ground surveys provided a
detailed, lateral depiction of conductive zones, the most
probable pathways for groundwater flow. These surveys also
identified near-surface areas that may contain elevated
concentrations of sulfide minerals that weather to produce acid
groundwater. 相似文献
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Fouzan Al-Fouzan William Harbert Robert Dilmore Richard Hammack James Sams Garret Veloski Terry Ackman 《Mine Water and the Environment》2004,23(1):28-33
Abstract. A geophysical analysis was conducted over the abandoned
T&T subsurface mines and portions of the Muddy and Roaring
Creek watersheds in northeastern Preston County, West Virginia.
The data were collected using helicopter-borne measurements of
frequency-domain electromagnetic (FDEM) conductivity (390, 1555,
6254, 25,800, and 102,680 Hz). Noise was a significant issue in
the lowest frequency EM conductivity data, especially the 390 Hz
and 1555 Hz data; noise removal was accomplished by standard
spatial frequency filtering, using homomorphic filters and
Fourier filtering along individual flight lines. We interpret
the filtered FDEM apparent conductivities and apparent
resistivities as showing regions of potential mine pools and
regions of contrasting groundwater conductivity related to
discharge. 相似文献
5.
Abstract. Nighttime high-resolution airborne thermal infrared
imagery (TIR) data were collected in the predawn hours during
Feb 5-8 and March 11-12, 1999, from a helicopter platform for
72.4 km of the Youghiogheny River, from Connellsville to
McKeesport, in southwestern Pennsylvania. The TIR data were used
to identify sources of mine drainage from abandoned mines that
discharge directly into the Youghiogheny River. Image-processing
and geographic information systems (GIS) techniques were used to
identify 70 sites within the study area as possible mine
drainage sources. The combination of GIS datasets and the
airborne TIR data provided a fast and accurate method to target
the possible sources. After field reconnaissance, it was
determined that 24 of the 70 sites were mine drainage. This
paper summarizes: the procedures used to process the TIR data
and extract potential mine-drainage sites; methods used for
verification of the TIR data; a discussion of factors affecting
the TIR data; and a brief summary of water quality. 相似文献
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R.?W.?HammackEmail author E.?I.?Love G.?A.?Veloski T.?E.?Ackman W.?Harbert 《Mine Water and the Environment》2003,22(2):80-84
Abstract. Helicopter-mounted electromagnetic (HEM) surveys have been
used to delimit conductive mine pools and groundwater features
at various areas in the eastern United States that contain
abandoned surface and underground coal mines. HEM was used to
delineate the source areas and flow paths for acidic,
metal-containing groundwater. This will aid remediation efforts.
A recent HEM survey of Kettle Creek Watershed, Clinton County,
Pennsylvania, using a 6-frequency electromagnetic data
acquisition system, is presented. The survey accurately located
conductive pools within underground mines, acidgenerating mine
spoil at surface mines, and areas of groundwater recharge and
discharge. 相似文献
7.
Abstract. High-resolution airborne thermal infrared (TIR) imagery
data were collected over 90.6 km2 (35
mi2) of remote and rugged terrain in
the Kettle Creek and Cooks Run Basins, tributaries of the West
Branch of the Susquehanna River in north-central Pennsylvania.
The purpose of this investigation was to evaluate the
effectiveness of TIR for identifying sources of acid mine
drainage (AMD) associated with abandoned coal mines. Coal mining
from the late 1800s resulted in many AMD sources from abandoned
mines in the area. However, very little detailed mine
information was available, particularly on the source locations
of AMD sites. Potential AMD sources were extracted from airborne
TIR data employing custom image processing algorithms and GIS
data analysis. Based on field reconnaissance of 103 TIR
anomalies, 53 sites (51%) were classified as AMD. The AMD
sources had low pH (<4) and elevated concentrations of iron
and aluminum. Of the 53 sites, approximately 26 sites could be
correlated with sites previously documented as AMD. The other 27
mine discharges identified in the TIR data were previously
undocumented. This paper presents a summary of the procedures
used to process the TIR data and extract potential mine drainage
sites, methods used for field reconnaissance and verification of
TIR data, and a brief summary of water-quality data. 相似文献
8.
J Veloski M Hojat JB Erdmann JS Gonnella 《Canadian Metallurgical Quarterly》1998,279(7):508-9; author reply 510
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