Mangrove recruitment after forest disturbance is facilitated by herbaceous species in the Caribbean.

Plant communities along tropical coastlines are often affected by natural and human disturbances, but little is known about factors influencing recovery. We focused on mangrove forests, which are among the most threatened ecosystems globally, to examine how facilitation by herbaceous vegetation might improve forest restoration after disturbance. We specifically investigated whether recovery of mangrove forests in harsh environments is accelerated by nurse plants and whether the beneficial effects are species-specific. Quantification of standardized effects allowed comparisons across performance parameters and over time for: (1) net effect of each herbaceous species on mangrove survival and growth, (2) effects of pre- and post-establishment factors associated with each herbaceous species, and (3) need for artificial planting to enhance growth or survival of mangrove seedlings. Mangrove recruitment in a clear-cut forest in Belize was accelerated by the presence of Sesuvium portulacastrum (succulent forb) and Distichlis spicata (grass), two coastal species common throughout the Caribbean region. The net effect of herbaceous vegetation was positive, but the magnitude of effects on mangrove survival and growth differed by species. Because of differences in their vegetative structure and other features, species effects on mangroves also varied by mechanism: (1) trapping of dispersing propagules (both species), (2) structural support of the seedling (Distichlis), and/or (3) promotion of survival (Sesuviumn) or growth (Distichlis) through amelioration of soil conditions (temperature, aeration). Artificial planting had a stronger positive effect on mangrove survival than did edaphic conditions, but planting enhanced mangrove growth more in Sesuvium than in Distichlis patches. Our study indicates that beneficial species might be selected based on features that provide multiple positive effects and that species comparisons may be improved using standardized effects. Our findings are not only relevant to the coastal environments found in the Caribbean region, but our assessment methods may be useful for developing site-specific information to restore disturbed mangrove forests worldwide, especially given the large pool of mangrove associates (>45 genera) available for screening.     

Characterization of airborne particles at a high-btu coal-gasification pilot plant

Airborne particles in fugitive emissions have been measured at a slagging fixed-bed coal-gasification pilot plant using lignite. Sampling was conducted during shutdown operations and opening of the gasifier following an aborted startup. Aerosol collected with a Sierra high-volume impactor was subjected to analysis by gas chromatography, mass spectrometry, and scanning electron microscopy; aerosol collected with an Andersen low-volume impactor was subjected to flameless atomic absorption analysis. The data show that the bulk of the trace organic material is associated with small particles: these data are similar to data on ambient air reported in the literature. Particle morphologies resemble those of fly ash from coal combustion, including smooth spheres, vesicular spheres, and crystalline material. Trace element size distributions are bimodal and resemble data for ambient air. Pb-containing particles are generally submicron, while particles containing Al, Fe, and other crustal species are mostly of supermicron size. Aluminum-based aerosol enrichment factors calculated from the lignite composition show that the composition of the aerosol resembles that of the coal, with the exception of modest enrichments of Mg, Na, As, and Pb in the submicron size range. Aerosol enrichment factors based on the earth's crustal composition are somewhat greater than those based on coal composition for several elements, suggesting potential errors in using crustal enrichment data to investigate chemical fractionation during aerosol formation.     

Aqueous Extracts of <Emphasis Type="Italic">Hibiscus sabdariffa</Emphasis> Calyces to Control Aichi Virus

Aqueous Hibiscus sabdariffa extracts possess antimicrobial properties with limited information available on their antiviral effects. Aichi virus (AiV) is an emerging foodborne pathogen that causes gastroenteritis. Vaccines are currently unavailable to prevent their disease transmission. The objective of this study was to determine the antiviral effects of aqueous H. sabdariffa extracts against AiV. AiV at ~5 log PFU/ml was incubated with undiluted (200 mg/ml), 1:1 (100 mg/ml) or 1:5 (40 mg/ml) diluted aqueous hibiscus extract (pH 3.6), phosphate-buffered saline (pH 7.2 as control), or malic acid (pH 3.0, acid control) at 37 °C over 24 h. Treatments were stopped by serially diluting in cell-culture media containing fetal bovine serum and titers were determined using plaque assays on confluent Vero cells. Each treatment was replicated thrice and assayed in duplicate. AiV did not show any significant reduction with 1:1 (100 mg/ml) or 1:5 (40 mg/ml) diluted aqueous hibiscus extracts or malic acid after 0.5, 1, or 2 h at 37 °C. However, AiV titers were reduced to non-detectable levels after 24 h with all the three tested concentrations, while malic acid showed only 0.93 log PFU/ml reduction after 24 h. AiV was reduced by 0.5 and 0.9 log PFU/ml with undiluted extracts (200 mg/ml) after 2 and 6 h, respectively. AiV treated with 1:1 (100 mg/ml) and 1:5 (40 mg/ml) diluted extracts showed a minimal ~0.3 log PFU/ml reduction after 6 h. These extracts show promise to reduce AiV titers mainly through alteration of virus structure, though higher concentrations may have improved effects.     

Using discrete choice experiments to assess the preferences of new mining workforce to commute or relocate to the Surat Basin in Australia

Two choice modelling experiments have been used to examine how residents of a major urban centre would consider commuting or relocation options if they were to consider taking up employment in a rapidly growing resource region. The case study area focused on the Surat Basin in southern Queensland where recent increases in mining activity involve both coal mining and coal seam gas extraction. The preferences of residents of Brisbane, the state capital and closest major centre to the Surat Basin, were assessed in the experiment. The results identified increased salary as the most important factor, but respondents were also concerned about potentially offsetting influences such as high living costs and accommodation affordability/availability. Respondents indicated that the additional salary needed to take up employment in the Surat Basin was substantially higher for relocation options than for FIFO options.     

Stationary sources of airborne lead: a comparison of emissions data for southern California

Estimates for the air releases of lead from stationary point sources are considered for the South Coast Air Basin of California. We have examined four databases published by U.S. Environmental Protection Agency, the California Air Resources Board, and the South Coast Air Quality Management District. Our analysis indicates that none of the databases includes every emitting facility in the South Coast Air Basin of California and that other discrepancies among the databases exist. Additionally, the data have been analyzed for temporal variation, and some of the California Air Resources Board data are not current. The South Coast Air Quality Management District inventory covers 12 times more facilities in 2001 than in 1996. From this analysis, we conclude that all four of the databases would benefit by sharing data, increasing transparency, analyzing uncertainty, and standardizing emission estimation methods.     

Some psychological consequences of striking: A six month,longitudinal study

The literature available on organizational psychology has largely neglected the issue of industrial conflict, and little is known about individual psychological effects of industrial conflict such as labour disputes and strikes. Psychological consequences of involvement in a strike were assessed in this research. Data were collected from 117 full-time, white collar union members immediately following a 22 day strike, and again two and six months later. Negatively perceived industrial relations events (e.g. 'strike or lockout', 'being involved in negotiations') were associated with marital adjustment, psychosomatic symptoms and a lack of psychological well-being on completion of the strike, and predicted unfavourable changes in psychological well-being over the next two and six months. A framework for understanding the negative effects of labour disputes and strikes is proposed, and the role of the organizational psychologist when such conflicts occur is considered.     

Sodium and chloride accumulation in leaf, woody, and root tissue of Populus after irrigation with landfill leachate

The response of Populus to irrigation sources containing elevated levels of sodium (Na(+)) and chloride (Cl(-)) is poorly understood. We irrigated eight Populus clones with fertilized well water (control) (N, P, K) or municipal solid waste landfill leachate weekly during 2005 and 2006 in Rhinelander, Wisconsin, USA (45.6 degrees N, 89.4 degrees W). During August 2006, we tested for differences in total Na(+) and Cl(-) concentration in preplanting and harvest soils, and in leaf, woody (stems+branches), and root tissue. The leachate-irrigated soils at harvest had the greatest Na(+) and Cl(-) levels. Genotypes exhibited elevated total tree Cl(-) concentration and increased biomass (clones NC14104, NM2, NM6), elevated Cl(-) and decreased biomass (NC14018, NC14106, DM115), or mid levels of Cl(-) and biomass (NC13460, DN5). Leachate tissue concentrations were 17 (Na(+)) and four (Cl(-)) times greater than water. Sodium and Cl(-) levels were greatest in roots and leaves, respectively.     

The long-term environmental behaviour of strontium and barium released from former mine workings in the granites of the Sunart region of Scotland, UK

The concentrations of strontium and barium have been measured in water, sediment and the shells of mussels (Mytilus edulis) from a river system in the Sunart region of Scotland, UK. The aim was to establish the fate and mobility of these elements, which are slowly being released from old mine workings on the Strontian granites. Enhanced strontium (1500-2000 microg l(-1) and 250-290 microg l(-1)) and barium concentrations (316 microg l(-1) and 83 microg l(-1)) were found in the waters originating from the two mine drains studied. Both element were also found at significant levels in the river sediments taken from the vicinity of each drainage site (Sr: 225 microg g(-1) and 120-125 microg g(-1); Ba: 1380 microg g(-1) and 126-170 microg g(-1)). The data suggests that the sediments are acting as a reservoir for these group II cations from where they become distributed throughout the river system. Strontium is found to be incorporated into the shells (3.16-3.46 microg g(-1)) and pearls (3.57 microg g(-1)) of the blue mussel, located at the estuarine margin some 10 km downstream, at values close to the maximum expected (3.3% by weight of the calcium content). The study presents a view of the fate of barium and strontium in a river system over a prolonged period of time. As such it provides valuable information for studies that seek to model the impact of the accidental release of barium and strontium (including the important radionuclide 90Sr) into the environment.     

Road safe seniors: Screening for age-related driving disorders in inpatient and outpatient settings

Introduction

Older drivers are increasing in number and they often have health conditions that place them at high risk for motor-vehicle crashes (MVC). Screening is underutilized, and is rarely done in hospital settings.

Methods

A convenience sample of 755 older adults completed age related driving disorders screening at University of California, San Diego inpatient and outpatient health centers. Screening included three strength/frailty tests, two vision tests (acuity and fields), and two cognitive tests, based on AMA recommendations. The average age of participants was 72.5; 55.5% were male and 94% English-speaking; 17.8% of older adults failed at least one aspect of screening.

Results

In multivariate analysis, significant associations of failed status were age, male sex, selfrestrictions of driving, and inpatient screening locations. The screening identified one in six adults to be 'high-risk' for age related driving disorders. Screening was effective and feasible in both inpatient and outpatient settings.

Impact on industry

As the driving population ages, industry, government and health car providers need to plan for the management of driving impairments in older adults.