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The health status of immigrants is of vital interest to health policy planners as the number of immigrants in the United States increases. This report has shown that, overall, foreign-born persons had better health than the U.S.-born population, although this health advantage varied by length of residence in the United States. In virtually every measure of(More)
The problem of calibrating parametric sonar systems at low difference frequencies used in backscattering applications is addressed. A particular parametric sonar is considered: the Simrad TOPAS PS18 Parametric Sub-bottom Profiler. This generates difference-frequency signals in the band 0.5-6 kHz. A standard target is specified according to optimization(More)
The depth dependence of fish target strength has mostly eluded experimental investigation because of the need to distinguish it from depth-dependent behavioral effects, which may change the orientation distribution. The boundary-element method (BEM) offers an avenue of approach. Based on detailed morphometric data on 15 gadoid swimbladders, the BEM has been(More)
To establish the validity of the boundary-element method (BEM) for modeling scattering by swimbladder-bearing fish, the BEM is exercised in several ways. In a computation of backscattering by a 50-mm-diam spherical void in sea water at the four frequencies 38.1, 49.6, 68.4, and 120.4 kHz, agreement with the analytical solution is excellent. In computations(More)
Mapping perceptions of safety and danger in Medellin, Colombia: a study in the perceptual geography of urban crime" (2011). 2010 This thesis entitled: Mapping perceptions of safety and danger in Medellin, Colombia: a study in the perceptual geography of urban crime written The final copy of this thesis has been examined by the signatories, and we find that(More)
There are two high-level goals: to understand and quantify effects of mid-frequency (MF) sonar on fish and whale behavior through direct observation, and to investigate the potential usefulness of MF sonar in acoustic measurements of fish, including stock assessments. OBJECTIVES The initial objectives are to prove the usefulness of the Kongsberg TOPAS PS18(More)
Potential physical effects of sonar transmissions on marine mammals were investigated by measuring pressure fields induced in a 119-kg, 211-cm-long, young adult male common dolphin (Delphinus delphis) cadaver. The specimen was instrumented with tourmaline acoustic pressure gauges used as receiving sensors. Gauge implantation near critical tissues was guided(More)
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