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ItemTrichophycin A, a cytotoxic linear polyketide isolated from a Trichodesmium thiebautii bloom(MDPI, 1/6/2017) Bertin, Matthew J.; Wahome, Paul G.; Zimba, Paul V.; He, Haiyin; Moeller, Peter D. R.In an effort to isolate and characterize bioactive secondary metabolites from Trichodesmium thiebautii blooms, collected cyanobacteria biomass was subjected to bioassay-guided extraction and fractionation using the human colon cancer cell line HCT-116, resulting in the isolation and subsequent structure characterization of a linear polyketide trichophycin A (1). The planar structure of 1 was completed using 1D and 2D NMR spectroscopy and high-resolution electrospray ionization mass spectrometry (HRESIMS). Trichophycin A was moderately toxic against the murine neuroblastoma cell line Neuro-2A (EC50: 6.5 μM) and HCT-116 cells (EC50: 11.7 μM). Trichophycin A was significantly more cytotoxic than the previously isolated polyketides trichotoxin A and trichotoxin B. These cytotoxicity observations suggest that toxicity may be related to the polyol character of these polyketide compounds. ItemDISCARD MORTALITY, RECRUITMENT, AND CONNECTIVITY OF RED SNAPPER (LUTJANUS CAMPECHANUS) IN THE NORTHERN GULF OF MEXICO(11/10/2014) Curtis, Judson MatthewRed Snapper (Lutjanus campechanus) is the most economically important reef fish species in the Gulf of Mexico. Despite being intensively managed, stocks have been slow to recover from overharvest and the population is still rebuilding. One possible reason is that Red Snapper experience high discard mortality after catch-and-release. Additionally, there is a decoupling of the stock-recruit relationship in the fishery with high levels of recruitment despite low spawning stock biomass. This dissertation addressed these gaps in knowledge in three principal chapters. In Chapter II, I evaluated if certain release methods reduced discard mortality of Red Snapper at different depths and temperatures. I used acoustic telemetry to determine the best-release practices for enhancing survival and to estimate the extent of delayed mortality. Venting and rapid recompression release methods were more beneficial for enhancing survival, and delayed mortality events occurred within a 72-hour time period. In Chapter III, I used novel acoustic transmitters to analyze the post-release behavior and activity patterns of Red Snapper that survived catch-and-release. Red Snapper had different acceleration and depth activity over diel time periods, and increases in acceleration were correlated with higher depth in the water column. Release treatments did not affect long-term behavior and activity. In Chapter IV, I examined the stock-recruit relationship for the Red Snapper fishery by assessing whether localized cryptic spawning stock biomass is responsible for maintaining high recruitment levels. Acoustic telemetry and catch data were used to show that large, sow Red Snapper have high site fidelity and residency patterns in the western Gulf of Mexico, suggesting high recruitment observed in the stock may be originating locally from non-targeted sites. By identifying the source of the high spawning stock biomass, protection measures and regulations can be implemented to ensure that the current high recruitment to the fishery is sustained. Determining the best-release practices to enhance survival of discarded fish will result in larger stock sizes. Ultimately, implementation of findings from this dissertation into the management process will further assist and expedite the rebuilding of Red Snapper stocks and promote the recovery towards sustainability in this historically important Gulf of Mexico fishery. ItemINTERACTIONS BETWEEN SUSPENDED SEDIMENTS, NUTRIENTS AND(11/10/2014) Paudel, BhanuThe objectives of the present study were to identify the effects of freshwater inflow (FWI) on sediment transport and nutrients supply to estuaries, and the effects of sediments on nutrient supply at sediment-water interface. The Nueces River and its estuary, the Guadalupe River and its estuary, and the Lavaca-Colorado Estuary were selected for field studies. Laboratory experiments were conducted to test the study hypotheses, and data was analyzed using multivariate modeling and statistical approaches. In the Guadalupe Estuary, variability of suspended solids and nutrients were correlated with FWI, whereas in the Nueces and Lavaca-Colorado Estuary they were related with seasonal differences. Suspended solids in the estuaries increased during frontal events and during windy days. In some of the field samplings, stations closer to the Gulf of Mexico had higher suspended sediments than the stations closer to the river. The increase in suspended sediments increased ammonia concentration in the Guadalupe Estuary, phosphorus and silicate concentrations in the Nueces Estuary, and silicate concentration in the Lavaca-Colorado Estuary. The presence of silicate minerals in the estuaries maintains silicate concentration as well. Organic matter and calcium carbonate shells in sediments of the estuaries can bind phosphate, thus, may have played role in decreasing phosphate concentration in the water. Guadalupe River sediments, when transported to the estuary, can release ammonia at higher concentrations the river water concentration. Salinity in the estuary, thus, has a significant role in controlling nutrient concentrations. The release of ammonia by organic matter decomposition was lower in the Guadalupe Estuary than in the Nueces Estuary. The high inflow volumes in the Guadalupe Estuary may have washed away organic matter from the sediments and may have disturbed bacterial community resulting in the lower release of ammonia from Guadalupe Estuary sediments. The research performed here demonstrates the importance of sediments, organic matter, and inflow in maintaining nutrient concentrations in estuaries. Fluctuation of these nutrients can affect water quality, and hence, may influence the ecology of the estuary. ItemDISTRIBUTION AND DIVERSITY OF OCTOCORALS IN THE GULF OF MEXICO(11/11/2014) Etnoyer, Peter; T. C. ShirleyOctocorals are broadly distributed throughout the world’s oceans, from the shallow intertidal zone to deeper than 5800 meters. Fishermen refer to large colonies as ‘trees’. This is appropriate because colonies provide complex structural habitat for associated species, they are broadly distributed, and they are threatened by industrial practices, such as bottom trawling. Below the warm water layer (50 – 70 m deep), octocorals are presumed to be cosmopolitan in the West Atlantic, with a broadly homogenous distribution. This creates a problem for conservation and management because it is difficult to justify conservation of one place, if all others are the same. This dissertation tested the null hypothesis of no difference in octocoral assemblages at the three spatial scales (referred to as basin, region, and site scale) through meta-analysis of two large, original datasets. The first was 1881 records of octocoral occurrences in the Gulf of Mexico from cruise reports and museums. The second was 8495 seafloor images from six outer continental shelf banks, and one site between banks, in the northwestern Gulf region. Univariate, multivariate, and spatial analysis techniques were used to compare genera, depth zones, regions, and banks within a Geographic Information System framework.Octocoral assemblages in the Gulf of Mexico differed significantly between depth zones and regions, but there was no difference in diversity between depth zones less than 800 m, due to species replacement. Composition of octocoral assemblages varied significantly between sites, and hotspots for richness and abundance were evident within sites. Null hypotheses of no difference between banks, depth zones, and regions were rejected with confidence. The findings support the broad distribution of octocorals in the Gulf of Mexico, but not homogeneity of octocoral assemblages. Based on these results, place-based conservation of deep octocoral habitat is justified, because some sites have higher diversity and abundance of octocorals than others. ItemBiological productivity associated with the serpulid reefs of Baffin Bay, Texas(1997-08) Hardegree, Beau; McKee, David A.; Prouty, Jennifer S.; Tunnell, John W.; Dunton, Kenneth H.The upper Laguna Madre and Baffin Bay-complex has long been noted for its abundant finfish populations despite its generally persistent hypersaline condition. The purpose of this present study was to determine the contribution of the serpulid worm reefs to the productivity of Baffin Bay. The primary focus of this thesis was to test the hypothesis that fish were larger and found in higher concentrations near the serpulid worm reefs in Baffin Bay, and to quantify the abundances of potential prey items associated with the reefs. In addition, I measured the productivity (by O2 evolution) of the epiphytic algae growing on the reefs and compared it to published seagrass studies in the upper Laguna Madre. Lastly, I examined the dependence of consumers on carbon fixed by these primary producers using stable carbon isotope ratios as tracers. A total of 5,396 individuals representing 35 fish species, were collected by trammel net during the study. Seven fish species (Mugil cephalus = 27.3 o/q Pogonias cromis = 20.2 %, Cynoscion nebulosus = 15.2 %, Leiostomus xanthurus = 12.1 %, Arius felis = 10.7 %, Lagodon rhomboides = 2.3 %, and Sciaenops ocel/atus = 1.1 %) comprised 89.0 % of the total catch. The overall ichythyofaunal catch rate was not significantly different between reef and non-reef sites and only a seasonal effect in the catch rate data was observed. Seasonal differences can be explained by the recruitment of fish into the bay in Spring and Summer. These seasonal peaks can be attributed to three species: Arius felis, Pogonias cromis, and Leiostomus xanthurus. No strong evidence was found to support the hypothesis that larger fish congregate around the serpulid worm reefs. ItemGeoid determination in the coastal areas of the Gulf of Mexico(2/24/2014) Song, HongzhiCoastal areas of the Gulf of Mexico are important for many reasons. This part of the United States provides vital coastal habitats for many marine species; the area has seen-ever increasing human settlement along the coast, ever increasing infrastructure for marine transportation of the nation's imports and exports through Gulf ports, and ever increasing recreational users of coastal resources. These important uses associated with the Gulf coast are subject to dynamic environmental and physical changes including: coastal erosion (Gulf-wide rates of 25 square miles per year), tropical storm surges, coastal subsidence, and global sea level rise. Coastal land subsidence is a major component of relative sea level rise along the coast of the Gulf of Mexico. These dynamic coastal changes should be evident in changes to the geoid along the coast. The geoid is the equipotential gravity surface of the earth, which the best fits the global mean sea level. The geoid is not only been seen as the most natural shape of the Earth, but also it serves as the reference surface for most of the height systems. By using satellites (GRACE mission) scientists have been able to measure the large scale geoid for the Earth. A small scale geoid model is required to monitor local events such as flooding, for example, flooding created by storm surges from hurricanes such as Katrina (2005), Rita (2005), and Ike (2008). The overall purpose of this study is to evaluate the accuracy of the local coastal geoid. The more precise geoid will enable to improve coastal flooding predictions, and will enable more cost effective and accurate measurement of coastal topography using global navigation satellite systems (GNSS). The main objective of this study is to devise mathematical models and computational methods to achieve the best possible precision for evaluation of the geoid in the coastal areas of the Gulf of Mexico. More specifically, the numerical objectives of this study are 1) to obtain a continuous map of gravity anomalies and a continuous map of gravity by using spatial interpolation methods and to evaluate errors; 2) to solve the Laplace boundary value problem and evaluate errors; 3) to evaluate precision of the local geoid by using geospatial statistical tools and numerical techniques. This dissertation investigates modeling of the geoid, especially the gravimetric equipotential surface that approximates mean sea level, in the coastal areas of the Gulf of Mexico as well as errors in the geoid determination. The document begins with Chapter 1 which introduces the study of this dissertation. Different models of kriging are used to determine the precision of the geoid based on the free-air gravity anomalies data supplied by United States Naval Research Laboratory and the airborne gravity data provided by the U.S. National Geodetic Survey, which can be found in Chapters 2 and 3. Research in Chapters 2 shows that more precise evaluation of errors in gravity anomalies can be achieved by using different models of kriging. Results from Chapters 2 and 3 show that ordinary kriging with the stable semivariogram model provide better predictions. Research results from Chapter 3 provide estimation of maximum possible errors in the calculation of the geoid undulation. The dissertation also investigates behavior of gravity equipotential surfaces around coastal lines and its impact on the geoid evaluation. Chapters 4 and 5 are about evaluation of errors in the Dirichlet problem for calculation of gravity potential with uncertain boundary and boundary values has been achieved by solving the Laplace equation by means of separation of variables. Research has provided a theoretical model in Chapter 4 to estimate very small changes in gravimetric potential relative to the coast. Maximum possible error in the solution of Direchlet problem is determined in Chapter 5. Maximum possible error depends on the errors of boundary values and the precision of the boundary itself. Chapter 6 describes a novel approach to sea level rise modeling. Factor analysis is used to analyze local and global sea level rise and relationships between changing sea levels, currents, and the shape of the Earth. Results of factor analysis from Chapter 6 show that the elevation of sea level relates to the geoid and ocean circulation. Chapter 7 describes the relationship between the geoid and wetlands modeling. Research in Chapter 7 shows that the predicted continuous elevation map obtained through the ordinary stable kriging was sufficiently precise and fairly reliable. Chapter 7 is an exploratory chapter, and the ideas of this chapter will help the future research. ItemEstimated increase in inundation probability with confidence intervals for the Gulf of Mexico(2/25/2014) Warner, Natalya N.The main objective of this research is to study the impact of sea level rise on the relative increase in frequency of inundation for the low-lying coastal zones of the Gulf of Mexico caused by storms of different sizes. The research is based on locations around the Gulf of Mexico that benefit from existing long term sea level records and are located near population centers: Galveston Pier 21, Galveston Pleasure Pier, Port Isabel, Rockport, Texas, Grand Isle, La, and Pensacola, Key West, and St Petersburg, Florida stations. The stations' long-term water level records are divided into a long term sea level trend, a tidal component and a stationary surge component. Several extreme value distributions, such as three and four parameters Burr, Dagum, log-logistic, and generalized extreme value distribution (GEV), are compared using multiple statistical measures for the modeling of maximum annual storm surges. While differences are small the GEV and log logistic distributions are selected for this work based on performance, sensitivity to the series outliers and ease of implementation. Increases in inundation frequencies are computed by combining the stations' respective annual maximum surge models with two possible sea level rise scenarios, a conservative linear continuation of the past century trend and a scenario based on the upper limit of the sea level range in the IPCC (Intergovernmental Panel on Climate Change) AR4 report (Assessment Report 4), i.e. the A1FI scenario. Differences in oceanographic setting are discussed and affect vulnerability to sea level rise. To compare vulnerability to sea level rise, the ratios of future and present exceedance probabilities are computed for a range of water levels. The locations' respective vulnerabilities to sea level rise are assessed by comparing the maximum ratios of future to present water level exceedance probabilities and the corresponding water levels. Water levels at maximum ratios have a strong correlation with most common moment- and quantile - based statistics of surges, except the maximum annual surges. This indicates that the results of this study are not overly sensitive to the most extreme values or largest surge on the record provided that the record includes at least one large surge. Statistical bootstrap methods are used to estimate 90% and 95% confidence intervals for increases in inundation probability. For most cases the confidence intervals show a substantial decrease in interval width for stations with lengths of datasets of 50 years or longer indicating a preferred data length provided that a large surge event is included. For all locations the lower bounds of the confidence intervals imply significant increase in exceedance probabilities for both sea level rise scenarios. While expected increases in inundation frequencies are substantial for all stations, the results show considerable variation depending on the sizes of the surges, the station locations and the sea level rise scenarios. Annual maximum water levels resulting from small storms/surges will have higher frequencies, typically by a factor of 3 or more, than the historical frequency of water levels resulting from large hurricanes. As a result more frequent, smaller storm surges may have a larger impact on coastal communities than the effects of the less frequent, larger storm surges. Ratios of the exceedance probabilities depend mostly on sea level trends and the shape of the curves of the exceedance probabilities. The relative importance of these parameters depends on the sea level rise scenario. For a continued linear sea level rise maximum ratios are strongly correlated to the sea level trends or vertical land motion. For the conservative sea level rise scenario the study's highest increase in water level exceedance probability of 17 times is computed for a water level of 1.23m above present mean sea level for Grande Isle, Louisiana. For higher rates of global sea level rise local subsidence becomes less important and the dominant factor becomes the range of the locations' surges. For the study's A1FI based sea level rise scenario, the highest increase in water level exceedance probability is over 100 times for a water level of 0.83m above present mean sea level for Key West, Florida. The results of this research provide coastal decision makers quantitative estimates of future inundation risks for two sea level rise scenarios and a calibrated method to compute such risks for more sea level rise scenarios. This research is relevant for engineers, planners, insurance executives, and others to take into account the increasing impacts of storm surges of various sizes as sea level rises. The results will help develop better insurance rates, plan structures, land-use zoning, and others as the century progresses. The models, methodology and estimates developed as part of this research may be used to estimate the time before specific locations may become economically uninhabitable due to surge inflicted damages as sea level rises. Particularly, it is expected that this work will allow better to quantify coastal vulnerability to sea level rise along the Gulf of Mexico. ItemTrinational governance to protect ecological connectivity: support for establishing an international Gulf of Mexico marine protected area network(2/25/2014) Nash, Harriet LouiseThe Gulf of Mexico is a semi-enclosed, international sea that is bordered by the United States, Mexico, and Cuba. The three nations share transboundary living marine resources that move freely across political borders. Each nation has a vested interest in protecting the sustainability of living marine resources and the state of the large marine ecosystem. Uncommon, hard-bottom, high-biodiversity habitats occur on the continental shelf within United States, Mexican, and Cuban waters. An existing ecological network connects these hard-bottom habitats via migratory patterns and passive transportation of pelagic organisms through oceanic currents. Regional marine policy is needed to protect transboundary connectivity and ensure sustainability of shared living marine resources. An international network of marine protected areas throughout the Gulf of Mexico would conserve high-biodiversity habitats and ecological connectivity, which preserves the ecosystem's natural resiliency to natural and anthropogenic threats. Legal systems, laws, and governance regimes of the United States, Mexico, Cuba, and the international arena vary. Although the regulatory frameworks differ among the nations, each has marine policy and governance objectives that support ecosystem-based management. Analysis of marine policy was conducted to propose a trinational policy approach to establish and administer the International Gulf of Mexico Marine Protected Area Network under existing law. Domestically, the three nations each have one or more agencies that regulate marine protected areas, and such agencies would likely administer a transboundary marine protected area network. Internationally, several treaties are in place to protect living marine resources in the Gulf of Mexico. The Cartagena Convention was identified as the treaty to best support creation of the International Gulf of Mexico Marine Protected Area Network based on the treaty's scope and ratification by all three Gulf-facing nations. Collaboration and negotiation under the treaty could support an international memorandum of understanding and creation of a trinational commission to establish and oversee the network. The marine protected area network would connect sites that share features or biota. Coral reef ecosystems are important sites in the Gulf of Mexico. Four well-studied coral reefs--Florida Keys, Flower Garden Banks, Veracruz Reef System, and Alacranes Reef--are cornerstones of connectivity. Selected coral and fish species that occur at the four cornerstone sites were explored as examples of stepping-stone connectivity among several sites on the continental shelf throughout the Gulf. The selected species exemplify biological connectivity and provide justification for regional connectivity in the human dimension also. Marine protected area practitioners from the United States, Mexico, and Cuba gathered at a workshop in July 2012 to create the International Gulf of Mexico Marine Protected Area Network. Trinational collaborators identified design parameters and candidate sites that demonstrate biophysical connectivity and can be linked through standardized governance methods for sustaining human and environmental health and well-being. Of the candidate sites identified, several are collections of sites that are unprotected or not comprehensively protected. One example is the South Texas Banks; a case study for site selection was performed for the group of sites. Few biological data are available for the South Texas Banks. Multivariate statistical tests were performed on geomorphic variables that collectively acted as an abiotic surrogate for biodiversity patterns for 12 outer-shelf South Texas Banks. The analysis culminated with a ranking tool to guide prioritization of future biological explorations and site selection for designation of marine protected areas. A minimum of five outer-shelf South Texas Banks was proposed for place-based protection and inclusion in the International Gulf of Mexico Marine Protected Area Network. Similar methodology can be applied to other multi-site candidates to refine the spatial design of the network. Analyses of marine policy, ecological connectivity, and biodiversity hotspots yielded results that serve as a foundation for the International Gulf of Mexico Marine Protected Area Network. The network's objectives are to preserve natural resiliency to adverse anthropogenic and natural disasters and phenomena, to protect ecological connectivity, and to conserve biodiversity through shared resources and management tools. Continued trinational communication and collaboration are critical for successful ecosystem-based management at the regional scale. Proper trilateral administration of the International Gulf of Mexico Marine Protected Area Network could mitigate adverse effects of chronic and episodic stressors and increase protection of the ecosystem's natural resiliency, connectivity, and biodiversity. ItemDevelopment of a green fluorescent protein-based laboratory curriculum(IUMBM Journals, 2005-01) Larkin, PatrickA laboratory curriculum has been designed for an undergraduate biochemistry course that focuses on the investigation of the green fluorescent protein (GFP). The sequence of procedures extends from analysis of the DNA sequence through PCR amplification, recombinant plasmid DNA synthesis, bacterial transformation, expression, isolation, and characterization of the protein by SDS-PAGE. A survey of participants found that the majority of them were performing most of these procedures for the first time and that participants found the exercises enjoyable and considered them a significant aid to their understanding of biochemistry, cell biology, and molecular genetics. ItemOptimization of 12 chiral analytes with 8 polymeric surfactants(Oxford Academic, 2008-10-01) Billiot, Eugene; Billiot, Fereshteh; Warner, IsiahThis manuscript discusses the results of studies that were performed to determine optimum capillary electrophoresis (CE) conditions for the enantiomeric resolution of twelve chiral analytes with eight amino acid based polymeric surfactants. The parameters that were optimized include pH, buffer type, and concentration of surfactant. The results indicated that the optimum conditions for enantiomeric separations with the amino acid based polymeric surfactants examined in this study using CE were analyte dependent, not surfactant dependent. In other words, the optimum conditions for a particular analyte were the same for all the amino acid based polymeric surfactants examined in this study. The results of these studies indicate that when using a large group of related amino acid based polymeric surfactants only a few surfactants need to be optimized for each analyte under study. These studies were limited to anionic surfactants that contain the amino acids glycine, L-alanine, L-valine, and L-leucine only. No inference can be necessarily drawn about surfactants containing other types of amino acids such as threonine and serine, which contain extra heteroatoms, or phenylalanine that has an aromatic moiety. ItemHabitat use patterns of newly settled southern flounder, paralichthys lethostigma, in Aransas–Copano Bay, Texas(Springer, 2008-10-31) Nañez-James, Suraida E.; Stunz, Gregory; Holt, Scott A.Southern flounder Paralichthys lethostigma populations have been declining in Texas during the past 25 years. Despite their economic importance, little is known about their juvenile habitat requirements. We examined habitat use patterns of newly settled southern flounder in three zones at varying distances from the Aransas Pass inlet in Aransas–Copano Bay by measuring densities using a beam trawl in replicate estuarine habitat types in each zone. Highest abundance occurred near the inlet in vegetated sandy areas and was lowest in nonvegetated muddy bottom in regions furthest from the inlet. We also examined a 25-year fisheries data set from Texas Parks and Wildlife Department to evaluate long-term spatiotemporal recruitment patterns in Aransas–Copano Bay. These data showed generally low recruitment during the past 25 years with highest abundance near the inlets. Our results support the importance of vegetated habitat types, especially those near tidal passes, and suggest a long-term decline in recruitment densities of southern flounder. ItemRole of science-based and adaptive management in allocating environmental flows to the Nueces estuary, Texas, use(WIT Press, 2009-06) Montagna, Paul A.; Hill, Erin M.; Moulton, B.The Nueces River System has been subject to adaptive management since construction of the Choke Canyon Reservoir in 1982. A special condition required the City of Corpus Christi to provide not less than 185 million cubic meters (151,000 ac-ft) of water per year to the Nueces Estuary through a combination of spills, releases, and return flows to maintain ecological health and productivity of living marine resources. However, no releases were made and salinities in Nueces Bay increased to hypersaline conditions during the drought period of 1988–1990 and the estuary was inverted where fresher water entered the delta on high tides. In contrast, the bay historically supported populations of shrimp and oysters generally requiring salinities in the range of 10–20 ppt. Beginning in May 1990, the Texas Water Commission issued a series of Orders requiring the City to meet the special conditions contained in their water right permit and provide for freshwater inflows to the estuary. Since 1990, a series of restoration activities, monitoring and experimental studies, and Order amendments has resulted in a stakeholder driven process that increased environmental health while providing a sustainable water supply to the region. However, with climate change and continued development, more changes are likely to occur in the future. The lesson learned is that the goal of achieving consensus can occur with a blend and balance of science and a stakeholder decision process. Keywords: freshwater inflow, wetlands, marsh, shellfish, dams, water resources. ItemThe effect of boat propeller scarring intensity on genetic variation in a subtropical seagrass species(De Gruyter, 2009-12-15) Larkin, Patrick; Heideman, Krista L.; Burfeind, Dana; Stunz, Gregory; Larkin, Patrick; Heideman, Krista L.; Burfeind, Dana; Stunz, GregoryWe report here the effect of one form of disturbance, boat propeller scarring, on genetic variation in the subtropical seagrass Halodule wrightii. We developed an amplified fragment length polymorphism assay to measure genetic var-aition in plots representing four levels of scarring intensity: reference (0% scarring), low (1–5%), moderate (5–15%) and severe (>15%). Although we found severely scarred plots to have the lowest, and moderately scarred plots to have the highest, mean genetic diversity estimates (He,P), differences among scarring levels were found to be non-significant(as0.05). Analysis of molecular variance also showed no significant effect of scarring intensity. While propeller scar-ring can cause significant habitat loss, scarring intensities of up to 20% may not yet have seriously affected those factors (population size, flowering density, recruitment, gene flow)that strongly influence population genetic variation. The relatively recent occurrence of this type of disturbance, how-ever, could mean that any long-term effects have yet to detected ItemExistence of a unique solution to a quasilinear elliptic equation(Elsevier, 2011-03-29) Denny, DianeThe purpose of this paper is to prove the existence of a unique classical solution u(x) to the quasilinear elliptic equation −∇ · (a(u)∇u) + v · ∇u = f , where u(x0) = u0 at x0 ∈ Ω and where n · ∇u = g on the boundary ∂Ω. We prove that if the functions a, f , v, g satisfy certain conditions, then a unique classical solution u(x) exists. Applications include stationary heat/diffusion problems with convection and with a source/sink, where the value of the solution is known at a spatial location x0 ∈ Ω, and where n · ∇u is known on the boundary. ItemMERIS retrieval of water quality components in the turbid Albemarle Pamlico sound estuary, USA(MDPI, 2011-04-01) Sokoletsky, Leonid G.; Lunetta, Ross S.; Wetz, Michael S.; Paerl, Hans W.Two remote-sensing optical algorithms for the retrieval of the water quality components (WQCs) in the Albemarle-Pamlico Estuarine System (APES) were developed and validated for chlorophyll a (Chl). Both algorithms were semi-empirical because they incorporated some elements of optical processes in the atmosphere, water, and air/water interface. One incorporated a very simple atmospheric correction and modified quasi-single-scattering approximation (QSSA) for estimating the spectral Gordon’s parameter, and the second estimated WQCs directly from the top of atmosphere satellite radiance without atmospheric corrections. A modified version of the Global Meteorological Database for Solar Energy and Applied Meteorology (METEONORM) was used to estimate directional atmospheric transmittances. The study incorporated in situ Chl data from the Ferry-Based Monitoring (FerryMon) program collected in the Neuse River Estuary (n = 633) and Pamlico Sound (n = 362), along with Medium Resolution Imaging Spectrometer (MERIS) satellite imagery collected (2006–2009) across the APES; providing quasi-coinciding samples for Chl algorithm development and validation. Results indicated a coefficient of determination (R2) of 0.70 and mean-normalized root-mean-squares errors (NRMSE) of 52% in the Neuse River Estuary and R2 = 0.44 (NRMSE = 75 %) in the Pamlico Sound—without atmospheric corrections. The simple atmospheric correction tested provided on performance improvements. Algorithm performance demonstrated the potential for supporting long-term operational WQCs satellite monitoring in the APES. ItemDifferences between two estimates of air-sea turbulent heat fluxes over the Atlantic Ocean(AGU, 2011-09-23) Santorelli, A.; Pinker, R. T.; Bentamy, Anas; Katsaros, K. B.; Drennan, W. M.; Mestas Nuñez, Marcos; Carton, J. A. Uncertainties in turbulent ocean-atmosphere heat flux estimates, both among the estimates and between them and ground truth, suggest that further comparisons are needed. We analyze estimates from the French Research Institute for Exploitation of the Sea (IFREMER) and the Woods Hole Oceanographic Institution's Objectively Analyzed air-sea Fluxes (WHOI OAFlux). The IFREMER products are based on satellite observations and the WHOI OAFlux ones on data from satellites, buoys, and ships assimilated into numerical analyses. We focus on the Atlantic sector (70°W–30°E, 45°S–45°N) during 1996–2005, where the variables that enter the bulk formulae for computing fluxes (wind speed, sea surface and air temperature, and specific humidity) can be evaluated against buoys in the Prediction and Research Moored Array in the Atlantic (PIRATA). Since WHOI assimilates PIRATA observations, we have added two independent buoy data sets: FETCH and ROMEO. To examine how each variable contributes to the difference between estimated and buoy fluxes, the method of Bourras (2006) is applied. His so-called Q terms showed that specific air humidity and air temperature contributed the most to the biases of IFREMER latent and sensible heat fluxes, respectively, at both independent buoys. For WHOI OAFlux products, deviations from FETCH values were mainly due to wind speed and sea surface temperature differences, while in comparison with ROMEO fluxes, WHOI OAFlux biases were primarily due to specific humidity and sea surface temperature estimates. Modified estimates of turbulent fluxes with the IFREMER approach using the 10 m specific humidity and air temperature products of Jackson et al. (2009) show significant improvement in three test cases at PIRATA buoys. ItemDevelopment of gene expression markers of acute heat-light stress in reef-building corals of the genus porites(PLOS ONE, 2011-10-26) Kenkel, Carly; Aglyamova, Galina; Alamaru, Ada; Bhagooli, Ranjeet; Capper, Roxana; Cunning, Ross; deVillers, Amanda; Haslun, Joshua; Hédouin, Laetitia; Keshavmurthy, Shashank; Kuehl, Kristin A.; Mahmoud, Huda; McGinty, Elizabeth S.; Montoya Maya, Phanor Hernando; Palmer, Caroline V.; Pantile, Raffaella; Sánchez, Juan A.; Schils, Tom; Silverstein, Rachel N.; Squiers, Logan B.; Tang, Pei-Ciao; Goulet, Tamar; Matz, Mikhail; Kenkel, Carly; Aglyamova, Galina; Alamaru, Ada; Bhagooli, Ranjeet; Capper, Roxana; Cunning, Ross; deVillers, Amanda; Haslun, Joshua; Hédouin, Laetitia; Keshavmurthy, Shashank; Kuehl, Kristin A.; Mahmoud, Huda; McGinty, Elizabeth S.; Montoya Maya, Phanor Hernando; Palmer, Caroline V.; Pantile, Raffaella; Sánchez, Juan A.; Schils, Tom; Silverstein, Rachel N.; Squiers, Logan B.; Tang, Pei-Ciao; Goulet, Tamar; Matz, MikhailCoral reefs are declining worldwide due to increased incidence of climate-induced coral bleaching, which will have widespread biodiversity and economic impacts. A simple method to measure the sub-bleaching level of heat-light stress experienced by corals would greatly inform reef management practices by making it possible to assess the distribution of bleaching risks among individual reef sites. Gene expression analysis based on quantitative PCR (qPCR) can be used as a diagnostic tool to determine coral condition in situ. We evaluated the expression of 13 candidate genes during heat-light stress in a common Caribbean coral Porites astreoides, and observed strong and consistent changes in gene expression in two independent experiments. Furthermore, we found that the apparent return to baseline expression levels during a recovery phase was rapid, despite visible signs of colony bleaching. We show that the response to acute heat-light stress in P. astreoides can be monitored by measuring the difference in expression of only two genes: Hsp16 and actin. We demonstrate that this assay discriminates between corals sampled from two field sites experiencing different temperatures. We also show that the assay is applicable to an Indo-Pacific congener, P. lobata, and therefore could potentially be used to diagnose acute heat-light stress on coral reefs worldwide. ItemStatic inflation and deflation pressure–volume curves from excised lungs of marine mammals(The Company of Biologists, 2011-11-15) Fahlman, Andreas; Loring, Stephen; Ferrigno, Massimo; Moore, Colby; Early, Greg; Niemeyer, Misty; Lentell, Betty; Wenzel, Frederic; Joy, Ruth; Moore, Michael J.Excised lungs from eight marine mammal species [harp seal (Pagophilus groenlandicus), harbor seal (Phoca vitulina), gray seal (Halichoerus grypush), Atlantic white-sided dolphin (Lagenorhynchus acutus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), long-finned pilot whale (Globicephala melas) and harbor porpoise (Phocoena phocoena)] were used to determine the minimum air volume of the relaxed lung (MAV, N=15), the elastic properties (pressure–volume curves, N=24) of the respiratory system and the total lung capacity (TLC). Our data indicate that mass-specific TLC (sTLC, l kg–1) does not differ between species or groups (odontocete vs phocid) and agree with that estimated (TLCest) from body mass (Mb) by applying the equation: TLCest=0.135 Mb0.92. Measured MAV was on average 7% of TLC, with a range from 0 to 16%. The pressure–volume curves were similar among species on inflation but diverged during deflation in phocids in comparison with odontocetes. These differences provide a structural basis for observed species differences in the depth at which lungs collapse and gas exchange ceases. ItemEstimated tissue and blood N2 levels and risk of decompression sickness in deep-, intermediate-, and shallow-diving toothed whales during exposure to naval sonar(Frontiers, 2012-05-10) Kvadsheim, Petter H; Miller, P. J. O.; Tyack, P. L.; Sivle, Lise Doksæter; Lam, F. P. A.; Fahlman, AndreasNaval sonar has been accused of causing whale stranding by a mechanism which increases formation of tissue N2 gas bubbles. Increased tissue and blood N2 levels, and thereby increased risk of decompression sickness (DCS), is thought to result from changes in behavior or physiological responses during diving. Previous theoretical studies have used hypothetical sonar-induced changes in both behavior and physiology to model blood and tissue N2 tension (PN2), but this is the first attempt to estimate the changes during actual behavioral responses to sonar. We used an existing mathematical model to estimate blood and tissue N2 tension (PN2) from dive data recorded from sperm, killer, long-finned pilot, Blainville’s beaked, and Cuvier’s beaked whales before and during exposure to Low- (1–2 kHz) and Mid- (2–7 kHz) frequency active sonar. Our objectives were: (1) to determine if differences in dive behavior affects risk of bubble formation, and if (2) behavioral- or (3) physiological responses to sonar are plausible risk factors. Our results suggest that all species have natural high N2 levels, with deep diving generally resulting in higher end-dive PN2 as compared with shallow diving. Sonar exposure caused some changes in dive behavior in both killer whales, pilot whales and beaked whales, but this did not lead to any increased risk of DCS. However, in three of eight exposure session with sperm whales, the animal changed to shallower diving, and in all these cases this seem to result in an increased risk of DCS, although risk was still within the normal risk range of this species. When a hypothetical removal of the normal dive response (bradycardia and peripheral vasoconstriction), was added to the behavioral response during model simulations, this led to an increased variance in the estimated end-dive N2 levels, but no consistent change of risk. In conclusion, we cannot rule out the possibility that a combination of behavioral and physiological responses to sonar have the potential to alter the blood and tissue end-dive N2 tension to levels which could cause DCS and formation of in vivo bubbles, but the actually observed behavioral responses of cetaceans to sonar in our study, do not imply any significantly increased risk of DCS.