Natural and Human-Induced Variability in Barrier-Island Response to Sea Level Rise

Storm-driven sediment fluxes onto and behind barrier islands help coastal barrier systems keep pace with sea level rise (SLR). Understanding what controls cross-shore sediment flux magnitudes is critical for making accurate forecasts of barrier response to increased SLR rates. Here, using an existing morphodynamic model for barrier island evolution, observations are used to constrain model parameters and explore potential variability in future barrier behavior. Using modeled drowning outcomes as a proxy for vulnerability to SLR, 0%, 28%, and 100% of the barrier is vulnerable to SLR rates of 4, 7, and 10 mm/yr, respectively. When only overwash fluxes are increased in the model, drowning vulnerability increases for the same rates of SLR, suggesting that future increases in storminess may increase island vulnerability particularly where sediment resources are limited. Developed sites are more vulnerable to SLR, indicating that anthropogenic changes to overwash fluxes and estuary depths could profoundly affect future barrier response to SLR

Barnegat Bay-Little Egg Harbor Estuary : case study of a highly eutrophic coastal bay system

Author Posting. © The Author(s), 2007. This is the author's version of the work. It is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Ecological Applications 17 (2007): S3–S16, doi:10.1890/05-0800.1.The Barnegat Bay-Little Egg Harbor Estuary is classified here as a highly eutrophic estuary based on application of NOAA’s National Estuarine Eutrophication Assessment model. Because it is shallow, poorly flushed, and bordered by highly developed watershed areas, the estuary is particularly susceptible to the effects of nutrient loading. Most of this load (~50%) is from surface water inflow, but substantial fractions also originate from atmospheric deposition (~39%), and direct groundwater discharges (~11%). No point source inputs of nutrients exist in the Barnegat Bay watershed. Since 1980, all treated wastewater from the Ocean County Utilities Authority's regional wastewater treatment system has been discharged 1.6 km offshore in the Atlantic Ocean. Eutrophy causes problems in this system, including excessive micro- and macroalgal growth, harmful algal blooms (HABs), altered benthic invertebrate communities, impacted harvestable fisheries, and loss of essential habitat (i.e., seagrass and shellfish beds). Similar problems are evident in other shallow lagoonal estuaries of the Mid-Atlantic and South Atlantic regions. To effectively address nutrient enrichment problems in the Barnegat Bay-Little Egg Harbor Estuary, it is important to determine the nutrient loading levels that produce observable impacts in the system. It is also vital to continually monitor and assess priority indicators of water quality change and estuarine health. In addition, the application of a new generation of innovative models using web-based tools (e.g., NLOAD) will enable researchers and decision-makers to more successfully manage nutrient loads from the watershed. Finally, the implementation of stormwater retrofit projects should have beneficial effects on the system.Financial support of the Barnegat Bay National Estuary Program and Jacques Cousteau National Estuarine Research Reserve is gratefully acknowledged

Calcium carbonate dissolution rates in hydrothermal vent fields of the Guaymas Basin

Analysis of bivalve shell fragments that were embedded in epoxy blocks, mounted on titanium stakes, and deployed by DSRV Alvin at 5 sites in the Southern Trough of the Guaymas Basin (27°00′N, 111°24.55′W; depth 2012 m) indicates significant variation of calcium carbonate dissolution in in situ exposures of more than 900 days. Arrays of shell fragments of six bivalve species (i.e., Bathymodiolus thermophilus, Calyptogena magnifica, Calyptogena sp., Corbicula fluminea, Crassostrea virginica and Mytilus edulis) were positioned −17 cm, −7 cm and −2.5 cm below the sediment-water interface and 2.5 cm, 7 cm and 17 cm above the sediment-water interface in hydrothermal vent fields of the basin. Maximum dissolution rates for both calcite (mean = 86 μm/yr) and aragonite (mean = 312 μm/yr) were found in epoxy blocks located at the deepest point sampled in the sediment column (depth = 17 cm). Minimum dissolution rates of calcite and aragonite were found 7 cm (mean = 26 μm/yr) and 2.5 cm (mean = 96 μm/yr) above the sediment-water interface, respectively. Intermediate rates of dissolution were recorded 17 cm above the sediment-water interface (mean = 40 μm/yr for calcite and 126 μm/yr for aragonite). Mean rates of aragonite dissolution ranged from 59 μm/yr (site 5; clam area) to 227 μm/yr (site 3; clam area), and those of calcite dissolution ranged from 13 μm/yr (site 3; clam area) to 94 μm/yr (site 4; bacterial mat area). Dissolution rates were consistently highest in the bacterial mat area (site 4; mean = 94 μm/yr for calcite and 223 μm/yr for aragonite). Rates of calcium carbonate dissolution reported here for hydrothermal vent fields of the Guaymas Basin compare favorably with those of Rose Garden (Galapagos Rift) and 21N (East Pacific Rise) hydrothermal vent sites. These results have important implications for assessing biological rate processes in deep-sea hydrothermal vent environments

Mutualism between ribbed mussels and cordgrass enhances salt marsh nitrogen removal

Salt marsh ecosystems have declined globally and are increasingly threatened by erosion, sea level rise, and urban development. These highly productive, physically demanding ecosystems are populated by core species groups that often have strong trophic interactions with implications for ecosystem function and service provision. Positive interactions occur between ribbed mussels (Geukensia demissa) and cordgrass (Spartina alterniflora). Mussels transfer particulate nitrogen from the water column to the marsh sediments, which stimulates cordgrass growth, and cordgrass provides predator and/or heat stress refuge for mussels. Here, we test mussel facilitation of two functions in salt marshes that relate to N removal: microbial denitrification and water filtration. Microcosm experiments revealed that the highest rates of N-2 production and nitrification occurred when mussels were present with marsh vegetation, suggesting that mussels enhanced coupling of the nitrification-denitrification. Surveys spanning the York River Estuary, Chesapeake Bay, showed that the highest densities of mussels occurred in the first meter for all marsh types with mainstem fringing (1207 +/- 265 mussels/m(2)) being the most densely populated. The mussel population was estimated to be similar to 197 million animals with a water filtration potential of 90-135 million L/hr. Erosion simulation models demonstrated that suitable marsh habitat for ribbed mussels along the York River Estuary would be reduced by 11.8% after 50 years. This reduction in mussel habitat resulted in a projected 15% reduction in ribbed mussel abundance and filtration capacity. Denitrification potential was reduced in conjunction with projected marsh loss (35,536 m(2)) by 205 g N/hr, a 16% reduction. Because of the predominant occurrence of ribbed mussels at the marsh seaward edge and because the highest proportional loss will occur for fringing marshes (20%), shoreline management practices that restore or create fringing marsh may help offset these projected losses

Safety and immunogenicity of novel 5T4 viral vectored vaccination regimens in early stage prostate cancer: a phase I clinical trial.

Prostate cancer (PCa) has been under investigation as a target for antigen-specific immunotherapies in metastatic disease settings for the last two decades leading to a licensure of the first therapeutic cancer vaccine, Sipuleucel-T, in 2010. However, neither Sipuleucel-T nor other experimental PCa vaccines that emerged later induce strong T-cell immunity. In this first-in-man study, VANCE, we evaluated a novel vaccination platform based on two replication-deficient viruses, chimpanzee adenovirus (ChAd) and MVA (Modified Vaccinia Ankara), targeting the oncofetal self-antigen 5T4 in early stage PCa. Forty patients, either newly diagnosed with early-stage PCa and scheduled for radical prostatectomy or patients with stable disease on an active surveillance protocol, were recruited to the study to assess the vaccine safety and T-cell immunogenicity. Secondary and exploratory endpoints included immune infiltration into the prostate, prostate-specific antigen (PSA) change, and assessment of phenotype and functionality of antigen-specific T cells. The vaccine had an excellent safety profile. Vaccination-induced 5T4-specific T-cell responses were measured in blood by ex vivo IFN-γ ELISpot and were detected in the majority of patients with a mean level in responders of 198 spot-forming cells per million peripheral blood mononuclear cells. Flow cytometry analysis demonstrated the presence of both CD8+ and CD4+ polyfunctional 5T4-specific T cells in the circulation. 5T4-reactive tumor-infiltrating lymphocytes were isolated from post-treatment prostate tissue. Some of the patients had a transient PSA rise 2-8 weeks following vaccination, possibly indicating an inflammatory response in the target organ. An excellent safety profile and T-cell responses elicited in the circulation and also detected in the prostate gland support the evaluation of the ChAdOx1-MVA 5T4 vaccine in efficacy trials. It remains to be seen if this vaccination strategy generates immune responses of sufficient magnitude to mediate clinical efficacy and whether it can be effective in late-stage PCa settings, as a monotherapy in advanced disease or as part of multi-modality PCa therapy. To address these questions, the phase I/II trial, ADVANCE, is currently recruiting patients with intermediate-risk PCa, and patients with advanced metastatic castration-resistant PCa, to receive this vaccine in combination with nivolumab. The trial was registered with the U.S. National Institutes of Health (NIH) Clinical Trials Registry (ClinicalTrials.gov identifier NCT02390063)

NLOAD : an interactive, web-based modeling tool for nitrogen management in estuaries

Author Posting. © Ecological Society of America, 2007. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Ecological Applications 17, Supple. (2007): S17–S30, doi:10.1890/05-1460.1.Eutrophication of estuaries is an increasing global concern that requires development of new tools to identify causes, quantify conditions, and propose management options that address this environmental problem. Since eutrophication is often associated with increased inputs of land-derived nitrogen to estuaries, we developed NLOAD, a user-friendly, web-based tool that brings together six different published models that predict nitrogen loading to estuaries and two models that estimate nitrogen concentrations in coastal waters. Here we describe each of the models, demonstrate how NLOAD is designed to function, and then use the models in NLOAD to predict nitrogen loads to Barnegat Bay, New Jersey (USA). The four models that we used to estimate nitrogen loads to Barnegat Bay, when adjusted, all had similar results that matched well with measured values and indicated that Barnegat Bay receives roughly 26 kg N·ha−1·yr−1. Atmospheric deposition was the dominant source of nitrogen to Barnegat Bay, followed by fertilizer nitrogen. Wastewater in Barnegat Bay is diverted to an offshore outfall and contributes no nitrogen to the system. The NLOAD tool has an additional feature that allows managers to assess the effectiveness of a variety of management options to reduce nitrogen loads. We demonstrate this feature of NLOAD through simulations in which fertilizer inputs to the Barnegat Bay watershed are reduced. Even modest cutbacks in the use of fertilizers on agricultural fields and lawns can be shown to reduce the amount of N entering Barnegat Bay.Support for the NLOAD tool came from the Cooperative Institute for Coastal and Estuarine Environmental Technologies (CICEET, CICEET-UNH grants #02-610 and #04-833). Additional funding was received from Environmental Defense

Passive and active ventricular elastances of the left ventricle

BACKGROUND: Description of the heart as a pump has been dominated by models based on elastance and compliance. Here, we are presenting a somewhat new concept of time-varying passive and active elastance. The mathematical basis of time-varying elastance of the ventricle is presented. We have defined elastance in terms of the relationship between ventricular pressure and volume, as: dP = EdV + VdE, where E includes passive (E(p)) and active (E(a)) elastance. By incorporating this concept in left ventricular (LV) models to simulate filling and systolic phases, we have obtained the time-varying expression for E(a )and the LV-volume dependent expression for E(p). METHODS AND RESULTS: Using the patient's catheterization-ventriculogram data, the values of passive and active elastance are computed. E(a )is expressed as: [Image: see text]; E(p)is represented as: [Image: see text]. E(a )is deemed to represent a measure of LV contractility. Hence, Peak dP/dt and ejection fraction (EF) are computed from the monitored data and used as the traditional measures of LV contractility. When our computed peak active elastance (E(a,max)) is compared against these traditional indices by linear regression, a high degree of correlation is obtained. As regards E(p), it constitutes a volume-dependent stiffness property of the LV, and is deemed to represent resistance-to-filling. CONCLUSIONS: Passive and active ventricular elastance formulae can be evaluated from a single-beat P-V data by means of a simple-to-apply LV model. The active elastance (E(a)) can be used to characterize the ventricle's contractile state, while passive elastance (E(p)) can represent a measure of resistance-to-filling

High Levels of Sediment Contamination Have Little Influence on Estuarine Beach Fish Communities

While contaminants are predicted to have measurable impacts on fish assemblages, studies have rarely assessed this potential in the context of natural variability in physico-chemical conditions within and between estuaries. We investigated links between the distribution of sediment contamination (metals and PAHs), physico-chemical variables (pH, salinity, temperature, turbidity) and beach fish assemblages in estuarine environments. Fish communities were sampled using a beach seine within the inner and outer zones of six estuaries that were either heavily modified or relatively unmodified by urbanization and industrial activity. All sampling was replicated over two years with two periods sampled each year. Shannon diversity, biomass and abundance were all significantly higher in the inner zone of estuaries while fish were larger on average in the outer zone. Strong differences in community composition were also detected between the inner and outer zones. Few differences were detected between fish assemblages in heavily modified versus relatively unmodified estuaries despite high concentrations of sediment contaminants in the inner zones of modified estuaries that exceeded recognized sediment quality guidelines. Trends in species distributions, community composition, abundance, Shannon diversity, and average fish weight were strongly correlated to physico-chemical variables and showed a weaker relationship to sediment metal contamination. Sediment PAH concentrations were not significantly related to the fish assemblage. These findings suggest that variation in some physico-chemical factors (salinity, temperature, pH) or variables that co-vary with these factors (e.g., wave activity or grain size) have a much greater influence on this fish assemblage than anthropogenic stressors such as contamination

Nycthemeral and Monthly Occupation of the Fish Assemblage on a Sheltered Beach of Baía Norte, Florianópolis, Santa Catarina State, Brazil

Interpreting fish community records is challenging for several reasons, including the lack of past ichthyofauna data, the cyclical temporal variations in the community, and the methodology employed, which usually underestimates fish assemblages. The objective of this study was to describe short-scale and meso-scale (nycthemeral period and months, respectively) temporal variations in the ichthyofauna composition and structure of a sheltered beach of Baía Norte (Florianópolis, Santa Catarina state, Brazil), using a capéchade net. Samples were collected monthly for a period of 48 hours. During the period from December 2010 to November 2011, a total of 19,302 individuals belonging to 89 species and 39 families were captured. The number of individuals that were sampled during the day and/or night was dependent on the sampling month. On average, the daytime assemblage was more abundant and different in structure and composition than the nighttime assemblage. Of the eight species that had the highest Index of Relative Importance (%IRI), five had higher variations (ANOVA F) between the day and night than between the months. This finding reinforced the need for sampling during both the day and night. The capéchade net effectively captured demersal and pelagic individuals in a broad range of sizes