Risk factors for mortality during the 2002 landslides in Chuuk, Federated States of Micronesia

This study examines health effects resulting from landslides in Chuuk during Tropical Storm Chata'an in July 2002, and suggests strategies to prevent future mortality. In August 2002, we conducted a cross-sectional survey to identify risk factors for mortality during landslides, which included 52 survivors and 40 surrogates for 43 decedents to identify risk factors for death. Findings suggest that 1) females had a higher mortality rate from this event than males, and 2) children aged 5–14 years had a 10-fold increase in mortality when compared with annual mortality rates from all causes. Awareness of landslides occurring elsewhere and knowledge of natural warning signs were significantly associated with lower risks of death; being outside during landslides was not associated with reduced mortality. In Chuuk, improving communication systems during tropical storms and increasing knowledge of natural warnings can reduce the risk for mortality during landslides.     

Ecological growth strategies in the seaweeds Gracilaria foliifera (Rhodophyceae) and Ulva sp. (Chlorophyceae): Soluble nitrogen and reserve carbohydrates

The seaweeds Gracilaria foliifera (Rhodophyceae) and Ulva sp. (Chlorophyceae) were grown in an outdoor continuous-flow system at both ambient incident light (I₀) and 0.13 I₀. During the winter, both species accumulated substantial soluble nitrogen reserves (up to 1020 g-at N·g dry wt^-1 in G. foliifera and 630 g-at N·g dry wt^-1 in Ulva sp.). The rate at which these N reserves were depleted was proportional to the growth rate. Seaweeds grown at 0.13 I₀ had lower growth rates and higher levels of soluble tissue N than plants grown at I₀. During the spring-summer growing season, peaks in tissue N followed nutrient peaks in the ambient seawater. Ulva sp. had higher nutrient uptake and growth rates than G. foliifera and showed greater fluctuations in soluble tissue N. This may characterize opportunistic seaweed species with high biomass turnover rates. At I₀, the levels of starch (up to 340 mg·g dry wt^-1 in G. foliifera and 170 mg·g dry wt^-1 in Ulva sp.) were highest during the spring and summer. During this period, fluctuations in starch content were inversely related to growth rate and soluble tissue N. Seaweeds grown at 0.13 I₀ did not accumulate starch. Neither species was found to overwinter with starch reserves.     

Measures of health,fitness, and functional movement among firefighter recruits

Aim. The purpose of this study was to examine the associations between various health and fitness measures and Functional Movement Screen? (FMS?) scores among 78 firefighter recruits. Methods. Relationships between FMS? scores and age, body mass index (BMI), sit and reach (S&R) distance, estimated maximal aerobic capacity (V˙_O2max), estimated one-repetition maximum squat (1RM-Squat_max), and plank endurance (%Plank_max) were examined. Results. Total FMS? scores were significantly correlated with BMI (r?=??0.231, p?=?0.042), estimated 1RM-Squat_max (r?=?0.302, p?=?0.007), and %Plank_max (r?=?0.320, p?=?0.004). Multiple regression analyses indicated that this combination of predictors significantly predicted (F(3, 74)?=?5.043, p?=?0.003) Total FMS? score outcomes and accounted for 17% of the total variance (R²?=?0.170). In addition, logistic regression analyses indicated that estimated 1RM-Squat_max also significantly predicted (χ²?=?6.662, df?=?1, p?=?0.010) FMS? group membership (≤14 or ≥15). Conclusion. These results suggest that the health and fitness measures of obesity (BMI), bilateral lower extremity strength (estimated 1RM-Squat_max), and core muscular endurance (%Plank_max) are significantly associated with functional movement patterns among firefighter recruits. Consequently, injury prevention programs implemented among firefighter recruits should target these aspects of health and fitness.     

Household willingness to pay for stream restoration on private and public land: Evidence from the Baltimore metropolitan region

Stream restoration is one of the most widely used interventions to mitigate urban stormwater impacts and improve water quality. Government agencies have typically focused urban stream restoration efforts on public lands that they already own, even though a substantial portion of stream miles in highly urbanized areas occur on privately owned land. Yet, limited research exists to distinguish household willingness to pay (WTP) for stream restoration occurring on private versus public land. In this study, we use a choice experiment to analyze how household WTP for stream restoration attributes vary by land ownership and distance to the restoration project. Our empirical results indicate that streambank stabilization approaches have positive WTP estimates that are substantially larger in magnitude than those related to riparian vegetation management for clearing or planting trees. In general, estimated total household WTP for each of the four restoration design scenarios on public land is higher than when the same restoration design is located on private land. Nonetheless, estimated household WTP for each restoration design scenario on private land is substantial, retaining the majority of the value found on public land in all cases.     

Radioactivity in trinitite six decades later

The first nuclear explosion test, named the Trinity test, was conducted on July 16, 1945 near Alamogordo, New Mexico. In the tremendous heat of the explosion, the radioactive debris fused with the local soil into a glassy material named Trinitite. Selected Trinitite samples from ground zero (GZ) of the test site were investigated in detail for radioactivity. The techniques used included alpha spectrometry, high-efficiency gamma-ray spectrometry, and low-background beta counting, following the radiochemistry for selected radionuclides. Specific activities were determined for fission products (90Sr, 137Cs), activation products (60Co, 133Ba, 152Eu, 154Eu, 238Pu, 241Pu), and the remnants of the nuclear fuel (239Pu, 240Pu). Additionally, specific activities of three natural radionuclides (40K, 232Th, 238U) and their progeny were measured. The determined specific activities of radionuclides and their relationships are interpreted in the context of the fission process, chemical behavior of the elements, as well as the nuclear explosion phenomenology.     

Photosynthetic and optical properties of the marine chlorophyte Dunaliella tertiolecta grown under fluctuating light caused by surface-wave focusing

Photosynthetic and optical properties of the marine chlorophyte Dunaliella tertiolecta Butcher were studied in response to irradiance fluctuations caused by surface-wave focusing. The experimental conditions simulated the prominent features of the light field (high average irradiance, spectral composition and statistical properties) in the uppermost few meters of the water column under sunny surface conditions. The properties of algae grown under high-frequency fluctuations were compared with control cells grown under constant light at the same average irradiance (800 mol quantam^-2s^-1). No significant differences were found for a number of parameters, including growth rate, cellular chlorophyll a and pigment ratios, photosynthetic unit size and density of Photosystem I reaction centers, the rate of photosynthesis at the growth irradiance, dark respiration, and in vivo fluorescence of chlorophyll a per cell. Photosynthetic parameters were not affected by whether the incident light for oxygen exchange measurements was fluctuating or constant. This was the case whether the cells had been previously acclimated to either fluctuating or constant irradiance. Such a photosynthetic response indicates that cells are accomplishing a time integration of the fluctuating light. In addition, although D. tertiolecta is capable of dramatically changing its optical properties in response to low or high growth irradiance levels, the refractive index of the cells, the efficiency factors for light absorption and scattering by individual cells, and chlorophyll-specific absorption and scattering coefficients of cell suspensions, were all very similar under high irradiance, whether or not wave focusing was present.Contribution to the program of GIROQ (Groupe Interuniversitaire de Recherches Océanographiques du Québec)     

A novel Vibrio sp. pathogen of the coral Pocillopora damicornis

A coral pathogen was isolated from the diseased tissue of Pocillopora damicornis in Zanzibar. The pathogenic bacterium, referred to as Vibrio coralyticus YB, was classified as a member of the genus Vibrio. Based on its 16S rDNA sequence, V. coralyticus is probably a new species. In controlled aquaria experiments at 26-29°C, inoculation of pure cultures of V. coralyticus YB either into the seawater or by direct contact onto the coral caused tissue lysis of P. damicornis fragments. At 29°C, lysis began as small white spots after 3-5 days, rapidly spreading so that by 2 weeks the entire tissue was destroyed, leaving only the intact bare skeleton. When an infected diseased coral was placed in direct contact with a healthy one, the healthy coral lysed in 2-4 days, further indicating that the disease was contagious. Inoculation with as few as 30 bacteria ml^-1 was sufficient to infect and lyse corals. Seawater temperature was a critical variable for the infectious process: infection and lysis occurred rapidly at 27-29°C, slowly at 26°C and was not observed at 25°C. The data suggest that the presence of V. coralyticus YB, even in low numbers, in seawater surrounding a coral reef will lead to tissue destruction of P. damicornis, when seawater temperatures rise.     

Nitrogen fixation by blue-green algae associated with the siphonous green seaweed Codium decorticatum: effects on ammonium uptake

Nitrogen fixation (acetylene reduction) at rates of up to 1.2 g N₂ g dry wt^-1 h^-1 was measured for the siphonous green seaweed Codium decorticatum. No nitrogenase activity was detected in C. isthmocladum. The nitrogenase activity was light sensitive and was inhibited by the addition of DCMU and triphenyl tetrazolium chloride. Additions of glucose did not stimulate nitrogen fixation. Blue-green algae (Calothrix sp., Anabaena sp., and Phormidium sp.) were implicated as the organisms responsible for the nitrogenase activity. They occurred in a reduced microzone within the C. decorticatum thallus where nitrogen fixation was optimized. Nitrogen fixation did not affect the kinetic constants for ammonium uptake in C. decorticatum (K_s=12.0 M, V_max=13.4 mol NH₃ g dry wt^-1 h^-1) determined using the perturbation method. Nevertheless, C. decorticatum thalli which fixed nitrogen had internal dissolved nitrogen concentrations which were over 1.4 times higher than in non-fixing thalli. This suggests that if C. decorticatum does derive part of its nitrogen requirement from the blue-green algae which it harbors, the transfer does not involve competition between this process and the uptake of ambient ammonium.     

Microbial metabolism of N-Phenyl-1-naphthylamine in soil, soil suspensions, and aquatic ecosystems

N-Phenyl-1-naphthylamine (PNA) was degraded and mineralized in nonsterile aquatic and terrestrial samples. Degradation in unsupplemented sewage and lake water was detected in 3 to 6 days with half-lives of 5 and 10 days, respectively. In sewage and lake water supplemented with a readily degradable carbon source, degradation began in 1 and 5 days with half-lives of 2 and 8 days, respectively. Sewage samples converted between 20 and 30% of labeled [¹⁴C]-PNA to ¹⁴CO₂ in 35 days while lake water samples reached 10% conversion to ¹⁴CO₂ in 12 days. Soil samples and soil suspensions converted from 15 to 35% of [¹⁴C]-PnA to ¹⁴CO₂ in 11 days. PNA was microbiologically converted in lake water to two products that were tentatively identified by gas-liquid chromatography and mass spectroscopy as dihydroxy and N-acetyl derivatives.