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Mangrove forests are vulnerable to accelerated sea-level rise associated with climate warming because they occupy a relatively narrow zone on the mid-to-upper-intertidal flats. The fate of these ecosystems largely depends on their capacity to accrete sediment at a rate sufficient to maintain their elevation relative to sea level. We investigated the role of biophysical processes and feedbacks controlling surface-elevation dynamics in a fluvial sediment-rich Avicennia marina mangrove forest (New Zealand) at seasonal-to-inter-annual timescales (over 9 years) using the Rod Surface Elevation Table method. We found that sediment accretion in the forest was not measurably enhanced by episodic and short-lived storm discharges from rivers nor by elevated sea levels during storms. Critically, the coupling of frequent onshore winds and resulting resuspension of intertidal muds, with the fortnightly cycle of spring tide inundation, controlled sediment delivery and resulting accretion rates of 13 to 47 mm y−1. In turn, net surface-elevation trends of 0 to 28 mm y−1 were dominated by the physical processes of sediment accretion and shallow subsidence due to seasonal desiccation and resulting compaction of the infrequently inundated forest platform (4 to 16 mm y−1). Our data suggest that monthly and seasonal variation in tidally controlled hydroperiod and sediment delivery rather than episodic storm events are important for the maintenance of mangrove elevation within the intertidal zone. [ABSTRACT FROM AUTHOR]

Purpose. Adults with physical disabilities tend to smoke at higher rates than smokers in the general population. No study to date, however, has assessed smoking prevalence and cessation among individuals with multiple sclerosis (MS). Such information is critically needed because smoking is more deleterious for individuals with MS than for smokers without MS and increases MS risk. Method. Questionnaires were sent to 700 National Multiple Sclerosis Society Rhode Island Chapter members. Results. Based on a 50% response rate, results demonstrated a 15.2% current smoker prevalence rate, which is lower than USA and Rhode Island general adult population averages. Individuals who smoked, however, tended to be heavy smokers, consuming 20 - 30 cigarettes daily, and had been smoking 10 years or longer. Smokers varied in their interest in quitting but seemed confident in their ability to do so. Respondents reported that it was difficult to quit because smoking was pleasurable; smoking was helpful in coping with boredom and with having MS; withdrawal symptoms were unpleasant; and treatment for tobacco dependence was expensive. Conclusions. Efficacious smoking cessation interventions for smokers with MS should be developed to address a critical health need for a population of highly nicotine-dependent smokers who face numerous obstacles to quitting. [ABSTRACT FROM AUTHOR]

This paper compares the ergonomic risk assessment of a task for the upper extremities as determined by Rapid Upper Extremity Assessment (RULA) and the Strain Index (SI). The ergonomic risk to the upper extremities of 244 automotive assembly plant tasks were evaluated using RULA and SI. The outcomes of each tool were compared for each task. Results from this study provide practical insight into the methods used in each tool. This study compared only the ergonomic risk outputs from each tool; it does not pursue the question of which tool best predicts injury. The kappa score was 0.11, indicating little agreement between the outputs of the two tools. This is supported by the lack of monotonicity with a gamma score of 0.1. These results indicate that the risk assessment outcome of these two ergonomic assessment tools for the upper extremities do not agree. [ABSTRACT FROM AUTHOR]

As part of a larger investigation of cancer in Uganda, we conducted a case-control study of conjunctival squamous cell carcinoma in adults presenting at hospitals in Kampala. Participants were interviewed about social and lifestyle factors and had blood tested for antibodies to HIV, KSHV and HPV-16, -18 and -45. The odds of each factor among 60 people with conjunctival cancer was compared to that among 1214 controls with other cancer sites or types, using odds ratios, estimated with unconditional logistic regression. Conjunctival cancer was associated with HIV infection (OR 10.1, 95% confidence intervals [CI] 5.2-19.4; P<0.001), and was less common in those with a higher personal income (OR=0.4, 95% CI 0.3-0.7; P<0.001)[corrected]. The risk of conjunctival cancer increased with increasing time spent in cultivation and therefore in direct sunlight (chi2 trend=3.9, P=0.05), but decreased with decreasing age at leaving home (chi2 trend=3.9, P=0.05), perhaps reflecting less exposure to sunlight consequent to working in towns, although both results were of borderline statistical significance. To reduce confounding, sexual and reproductive variables were examined among HIV seropositive individuals only. Cases were more likely than controls to report that they had given or received gifts for sex (OR 3.5, 95% CI 1.2-10.4; P=0.03), but this may have been a chance finding as no other sexual or reproductive variable was associated with conjunctival cancer, including the number of self-reported lifetime sexual partners (P=0.4). The seroprevalence of antibodies against HPV-18 and -45 was too low to make reliable conclusions. The presence of anti-HPV-16 antibodies was not significantly associated with squamous cell carcinoma of the conjunctiva (OR 1.5, 95% CI 0.5-4.3; P=0.5) and nor were anti-KSHV antibodies (OR 0.9, 95% CI 0.4-2.1; P=0.8). The 10-fold increased risk of conjunctival cancer in HIV infected individuals is similar to results from other studies. The role of other oncogenic viral infections is unclear. [ABSTRACT FROM AUTHOR]

Context: Although the cost-effectiveness and cost-benefit of influenza vaccination are well established for persons aged 65 years or older, the benefits for healthy adults younger than 65 years are less clear.Objective: To evaluate the effectiveness and cost-benefit of influenza vaccine in preventing influenza-like illness (ILI) and reducing societal costs of ILI among healthy working adults.Design: Double-blind, randomized, placebo-controlled trial conducted during 2 influenza seasons.Setting and Participants: Healthy adults aged 18 to 64 years and employed full-time by a US manufacturing company (for 1997-1998 season, n = 1184; for 1998-1999 season, n = 1191).Interventions: For each season, participants were randomly assigned to receive either trivalent inactivated influenza vaccine (n = 595 in 1997-1998 and n = 587 in 1998-1999) or sterile saline injection (placebo; n = 589 in 1997-1998 and n = 604 in 1998-1999). Participants in 1997-1998 were rerandomized if they participated in 1998-1999.Main Outcome Measures: Influenza-like illnesses and associated physician visits and work absenteeism reported in biweekly questionnaires by all participants, and serologically confirmed influenza illness among 23% of participants in each year (n = 275 in 1997-1998; n = 278 in 1998-1999); societal cost of ILI per vaccinated vs unvaccinated person.Results: For 1997-1998 and 1998-1999, respectively, 95% (1130/1184) and 99% (1178/1191) of participants had complete follow-up, and 23% in each year had serologic testing. In 1997-1998, when the vaccine virus differed from the predominant circulating viruses, vaccine efficacy against serologically confirmed influenza illness was 50% (P =.33). In this season, vaccination did not reduce ILI, physician visits, or lost workdays; the net societal cost was $65.59 per person compared with no vaccination. In 1998-1999, the vaccine and predominant circulating viruses were well matched. Vaccine efficacy was 86% (P =.001), and vaccination reduced ILI, physician visits, and lost workdays by 34%, 42%, and 32%, respectively. However, vaccination resulted in a net societal cost of $11.17 per person compared with no vaccination.Conclusion: Influenza vaccination of healthy working adults younger than 65 years can reduce the rates of ILI, lost workdays, and physician visits during years when the vaccine and circulating viruses are similar, but vaccination may not provide overall economic benefits in most years. JAMA. 2000;284:1655-1663. [ABSTRACT FROM AUTHOR]

An outbreak of St. Louis encephalitis (SLE) resulted in 28 cases of the disease in Harris County, Texas, in 1986. The cases occurred principally in Baytown, in eastern Harris County, but five cases were also recognized in Houston. The risk of illness increased sharply with age, and all five fatal cases were in persons >55 y. Case-control methods were used for the first time to study factors associated with the risk of acquiring SLE. Risk was associated with residences poorly sealed against mosquitoes (non-air-conditioned residences and those with inadequate screens). The number of hours spent outdoors and in outdoor activities, except sitting immediately outside residences, were not associated with risk. Our observations suggest that exposure to vector mosquitoes may have occurred indoors. No host factors were significantly associated with risk of acquiring SLE, but more cases were cigarette smokers and had family histories of hypertension or cerebrovascular disease. [ABSTRACT FROM PUBLISHER]