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Omnidirectional measurements of ambient noise versus depth in the Caribbean, Mediterranean, Arctic, Pacific, and Atlantic areas are presented. The shapes of the vertical ambient noise profiles spanning the water column at frequencies from 25 to 500 Hz are shown to be heavily influenced by passing ships. The qualitative features of average noise profiles measured by mid-water hydrophones can be explained with the aid of a straightforward model, and it is concluded that low-frequency omnidirectional ambient noise depth dependence is predictable. The sensitivity of the vertical noise profile to passing ships, coupled with noise predictability suggests that surveillance could be effected by a vertical string of hydrophones without coherent processing in areas of relatively light shipping. [ABSTRACT FROM AUTHOR]

Context: The United States has one of the highest fire fatality rates in the developed world, and three quarters of these deaths are in residential fires.Objective: To compare characteristics of those who die and those who survive in the same residential fire.Design: Data on fatal residential fires were collected from the medical examiner and interviews with local fire officials.Setting: North Carolina.Subjects: Persons in residential fires with at least 1 fatality in a 1-year period.Main Outcome Measure: Dying vs surviving a fatal residential fire that occurred with more than 1 person at home.Results: Of the 190 decedents, 124 (65%) were male, 78 (41%) were home alone, and 69 (53%) of 130 adults who had blood alcohol measured were intoxicated (blood alcohol content >22 mmol/L [100 mg/dL]). Of the 254 persons present during fires in which more than 1 person was at home, 112 died. Individuals more likely to die (high-vulnerability group) were younger than 5 years or 64 years or older, had a physical or cognitive disability, or were impaired by alcohol or other drugs (risk of death for group, odds ratio [OR], 4.01; 95% confidence interval [CI], 2.29-7.03). The presence of an adult with no physical or cognitive disabilities who was unimpaired by alcohol or other drugs (a potential rescuer) reduced the risk of death in the high-vulnerability group (OR, 0.49; 95% CI, 0.24-0.99) but not the low-vulnerability group. Overall, a functioning smoke detector lowered the risk of death (OR, 0.39; 95% CI, 0.18-0.83).Conclusions: Smoke detectors were equally effective in both low- and high-vulnerability populations. The high-vulnerability group was more likely to survive if, in addition to a smoke detector, a potential rescuer was present. Further research should seek to identify prompts that facilitate speedy egress from a burning structure and that can be incorporated into residential fire alarm systems. [ABSTRACT FROM AUTHOR]

Social class differences in mortality from causes of death amenable to medical intervention were examined. All deaths in New Zealand males aged 15–64 years during the periods 19757ndash;1977 and 1985–1987 were identified. Strong social class gradients in mortality from causes of death amenable to medical intervention were observed during both periods. Furthermore, social class inequalities were more pronounced for amenable causes of mortality than for non-amenable causes. However, a marked decline in the age-standardized mortality rate from amenable causes was observed, with the rate falling by 30% over the 10-year study period. This decline was twice as large as the drop in the non-amenable mortality rate. Despite the fall in the death rate from amenable causes, social class inequalities in mortality persisted among New Zealand men, with the lowest socioeconomic group experiencing a death rate from amenable causes of mortality that was 3.5 times higher than men in the highest socioeconomic group. [ABSTRACT FROM PUBLISHER]

Acoustic waves propagating on the surface of solid and hollow elastic cylinders immersed in water were observed and their characteristics shown to be consistent with theory. These waves were excited by an 11-μsec pulse, projected onto the cylindrical surface at an excitation angle given by sin 1(co/cs), where co is the velocity of sound in water and cs is the velocity of the surface wave. The waves may be observed, since they continually radiate energy back into the water at the excitation angle. Surface waves were observed to exist on pure (98%) aluminum, 304 stainless steel, and various aluminum-alloy cylinders. Circumference-to-wavelength ratios were varied from 10 to 400 to discern the dispersive effects owing to the curvature of the target. It was also found that inhomogeneities correlate with pure propagation characteristics in some of the targets. The waves observed on air- and water-filled cylinders immersed in water are shown to correspond to the symmetric and antisymmetric vibrations in the shell. [ABSTRACT FROM AUTHOR]