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Previous oil spills provide clear evidence that ecosystem restoration efforts are challenging, and recovery can take decades. Similar to the Ixtoc-I well blowout in 1979, the Deepwater Horizon (DWH) oil spill was enormous both in volume of oil spilled and duration, resulting in environmental impacts from the deep ocean to the Gulf of Mexico coastline. Data collected during the National Resource Damage Assessment showed significant damage to coastal areas (especially marshes), marine organisms, and deep-sea habitat. Previous spills have shown that disparate regions recover at different rates, with especially long-term effects in salt marshes and deep-sea habitat. Environmental recovery and restoration in the northern Gulf of Mexico are dependent upon fundamental knowledge of ecosystem processes in the region. Post-DWH research data provide a starting point for better understanding baselines and ecosystem processes. It is imperative to use the best science available to fully understand DWH environmental impacts and determine the appropriate means to ameliorate those impacts through restoration. Filling data gaps will be necessary to make better restoration decisions, and establishing new baselines will require long-term studies. Future research, especially via NOAA’s RESTORE Science Program and its state-based Centers of Excellence, should provide a path to understanding the potential for restoration and recovery of this vital marine ecosystem.

Previous oil spills provide clear evidence that ecosystem restoration efforts are challenging, and recovery can take decades. Similar to the Ixtoc 1 well blowout in 1979, the Deepwater Horizon (DWH) oil spill was enormous both in volume of oil spilled and duration, resulting in environmental impacts from the deep ocean to the Gulf of Mexico coastline. Data collected during the National Resource Damage Assessment showed significant damage to coastal areas (especially marshes), marine organisms, and deep-sea habitat. Previous spills have shown that disparate regions recover at different rates, with especially long-term effects in salt marshes and deepsea habitat. Environmental recovery and restoration in the northern Gulf of Mexico are dependent upon fundamental knowledge of ecosystem processes in the region. PostDWH research data provide a starting point for better understanding baselines and ecosystem processes. It is imperative to use the best science available to fully understand DWH environmental impacts and determine the appropriate means to ameliorate those impacts through restoration. Filling data gaps will be necessary to make better restoration decisions, and establishing new baselines will require long-term studies. Future research, especially via NOAA’s RESTORE Science Program and the state-based Centers of Excellence, should provide a path to understanding the potential for restoration and recovery of this vital marine ecosystem.

Although great progress has been made to advance the scientific understanding of oil spills, tools for integrated assessment modeling of the long-term impacts on ecosystems, socioeconomics and human health are lacking. The objective of this study was to develop a conceptual framework that could be used to answer stakeholder questions about oil spill impacts and to identify knowledge gaps and future integration priorities. The framework was initially separated into four knowledge domains (ocean environment, biological ecosystems, socioeconomics, and human health) whose interactions were explored by gathering stakeholder questions through public engagement, assimilating expert input about existing models, and consolidating information through a system dynamics approach. This synthesis resulted in a causal loop diagram from which the interconnectivity of the system could be visualized. Results of this analysis indicate that the system naturally separates into two tiers, ocean environment and biological ecosystems versus socioeconomics and human health. As a result, ocean environment and ecosystem models could be used to provide input to explore human health and socioeconomic variables in hypothetical scenarios. At decadal-plus time scales, the analysis emphasized that human domains influence the natural domains through changes in oil-spill related laws and regulations. Although data gaps were identified in all four model domains, the socioeconomics and human health domains are the least established. Considerable future work is needed to address research gaps and to create fully coupled quantitative integrative assessment models that can be used in strategic decision-making that will optimize recoveries from future large oil spills.

The filamentous fungus Ashbya gossypii is used for riboflavin biosynthesis on an industrial scale, but even the wild type displays overproduction. Because riboflavin overproduction was known to start at the transition between growth and stationary phase, it was suspected that overproduction was induced at low growth rates. However, chemostatic cultivations performed at different growth rates did not result in any detectable riboflavin formation. In this study, we report that it was not the final growth rate that triggered riboflavin overproduction but a decline in growth rate. Therefore, continuous fermenter cultivations with dilution rate shifts were performed. Peaks of riboflavin overproduction were observed in the wild type and in a RIB3placZ reporter strain after downshifts in dilution rate. Accumulation of riboflavin correlated with an increased expression of lacZ reporter activity. The step size of the downshifts corresponded to the peak size of riboflavin formation and reporter activity. Expression of further RIB genes encoding riboflavin biosynthetic enzymes was analyzed by RT-PCR. RIB mRNA levels of the ribulose-5-phosphate branch of the divided riboflavin biosynthesis pathway (RIB3, RIB4, and RIB5) were found to increase in the riboflavin production phase, whereas the RIB2 and RIB7 mRNA levels belonging to the GTP branch remained constant. We propose that a decline in growth rate triggers the increased expression of RIB3, RIB4, and RIB5 resulting in riboflavin overproduction. Because although a reduction in oxygen supply, temperature increase or decrease, or salt stress did affect growth, but neither did lead to riboflavin overproduction nor did induce RIB3 reporter expression, we conclude that declining nutrition must be the stress stimulus. Because about half of the cells in the hyphae of Ashbya gossypii did not accumulate riboflavin, the regulatory response on the cellular level can be estimated to be at least twice as great in comparison to what we detected as overall signals.

ZusammenfassungDer Platelet ADhesion Assay (PADA) ist eine POCT-fähige Methode zur quantitativen Bestimmung der Plättchenadhäsivität. Durch spezielle Polymerpartikel und Testbedingungen, die den physiologischen Verhältnissen im Organismus angepasst sind, wird aus einer Vollblutprobe direkt der aktuelle Funktionszustand der Blutplättchen bestimmt.Innerhalb kurzer Zeit, mit geringem Geräteaufwand und minimalem Probenvolumen ist auch ein therapeutisches Monitoring von Glykoprotein(GP)-IIb/IIIa- und ADP-Rezeptor-Antagonisten möglich. Während bei Gesunden die Dosis/Wirkungskurven der GP-IIb/IIIa-Antagonisten nur gering variieren, schwanken sie bei thrombophilen Patienten stark. Wirkungsunterschiede bis zur Arzneimittelresistenz treten auch beim ADP-Rezeptor-Antagonisten Clopidogrel auf. Ein therapeutisches Monitoring der GP-IIb/IIIa- und ADP-Rezeptorantagonisten ist essenziell und mittels PADA realisierbar – auch als Langzeit-Monitoring für ADP-Rezeptorantagonisten sowie zur Detektion einer Arzneimittelresistenz. Mit dem PADA ist eine individuelle Ex-vivo-Dosisrelation für GP-IIb/IIIa-Antagonisten möglich. Der PADA erlaubt die Diagnostik einer pathologisch veränderten Plättchenfunktion thrombophiler Patienten und durch die einfache Handhabung auch die Therapieüberwachung über längere Zeit.

Riboflavin (vitamin B2), essential in tiny amounts as a precursor for oxidoreductase coenzymes, is a yellow pigment. Although it causes cytotoxicity via photoinduced damage of macromolecules, several microorganisms are striking overproducers. A question, unanswered for decades, is whether riboflavin overproducers can benefit from this property. Here, we report an ultraviolet (UV) protective effect of riboflavin. The spores of Ashbya gossypii, a riboflavin-overproducing fungus, are more sensitive to UV than those of Aspergillus nidulans. The addition of riboflavin to suspensions improves the UV resistance of both spore types. Interestingly, we show that regulation of sporulation and riboflavin overproduction in A. gossypii are linked. In batch culture, both were elevated when growth ceased. At constant growth rates, obtained in a chemostat culture, neither was elevated. Supplementation of cultures by cAMP, a known stress signal, negatively affected sporulation as well as riboflavin overproduction, establishing a second, independent argument for the linkage.

The northwest (NW) Gulf of Mexico is marked by strong seasonal patterns in regional and mesoscale circulation and variable effects of riverine/estuarine discharge, which influence distributions of nutrients, phytoplankton biomass and primary production. During a series of five cruises in the NW Gulf of Mexico in 1993 and 1994, an extensive data set was collected including nutrients, phytoplankton biomass (chlorophyll a), and photosynthesis–irradiance (P–E) parameters. Primary production was estimated using P–E parameters in conjunction with profiles of biomass and irradiance. Relatively high biomass and primary production were observed in inner shelf waters during spring conditions of high river discharge. This was attributed to the retention of biomass and nutrients on the shelf by the combination of high river outflow and a westward flow along the inner shelf with consequent onshore Ekman component. During summer, when surface currents shifted towards the north and east, values of nutrients, biomass and primary production were relatively high east of Galveston Bay and decreased outward from the coast. This pattern was apparently a consequence of nutrient inputs from riverine, upwelling and benthic sources. Nutrients, biomass and productivity in the western portion of the study area in summer were generally lower as a result of the upcoast flow of oligotrophic offshore water. Inter-annual variability was observed between November 1993 and 1994 with higher biomass and productivity occurring in November 1993. This was partially attributed to higher river discharge prior to November 1993, retention of biomass and nutrients by the downcoast flow along the inner shelf, and possibly, injection of nutrients onto the shelf at the shelf break. Our findings demonstrate that the interaction of circulation and availability of light and nutrients are largely responsible for variations in primary production. Nitrogen appeared to be the primary limiting nutrient, however, a potential for phosphate limitation was also observed particularly during periods of higher river discharge. Light availability was a critical variable during the fall and winter months, when higher primary production was restricted to shallow waters where vertical mixing was constrained by bottom topography. In deep waters, counteractive changes in nutrient and light availability apparently resulted in minor temporal variation between seasons. The annual carbon production in the Louisiana–Texas (LATEX) continental shelf region was estimated to be 159 g C m−2 year−1, which is within the range of prior estimates for this region. Given that the area of the study region was approximately 140,000 km2, this would be equivalent to an areal carbon production of about 22.2 million metric tons.

A coupled biological and physical model was applied to study the influence of river discharge on biological variability on the Louisiana-Texas (LATEX) continental shelf. The physical part included a primitive-equation turbulent closure model, and the biological part was a simple phytoplankton (P), zooplankton (Z), and nutrient (N) model. The model was forced by freshwater discharge from the river and ran prognostically under initial conditions of springtime water stratification and a steady-state solution of the P-Z-N model with no horizontal dependence. A nutrient source was included at the mouth of the river. The model predicted a well-defined density frontal zone on the inner shelf. The biological field showed a region of high phytoplankton biomass in the whole water column near the coast and a moderately high biomass patch in the upper 10 m at the outer edge of the frontal zone. A high concentration dome of nutrients was found near the bottom within the frontal zone. New production of nutrients was high throughout the whole water column near the coast and in the upper 10 m at the outer edge of the density front, but lower in the frontal zone. The model results were in reasonable agreement with observational data taken from a May 1993 interdisciplinary survey on the LATEX shelf. Cross-shelf distribution of biological production varied significantly with direction of wind stress but not with the diurnal tide. The model results suggested that the bottom-rich nutrient distribution within the frontal zone was caused by the interaction of physical and biological processes. Physical processes caused the formation of an area of high nutrient concentration in the weak current region within the frontal zone. Subsequent biological processes limited the increase of nutrients in the upper euphotic zone and hence led to the bottom-rich nutrient pattern.

During April and May 1993, the typical south and southwestward directed flow over the Texas shelf interacted with current rings located just off the Texas shelf in the Gulf of Mexico. The rings, a cyclone/anticyclone eddy pair, were oriented such that water was transported onto the shelf between the rings and water was drawn from the shelf on the rings' offshore-directed limbs. A shelf convergence zone transported water to the shelf edge where some of the water became entrained between the cyclone/anticyclone pair. Active shelf-slope exchange such as that seen in the April-May 1993 episode may be a more typical example of synoptic shelf circulation than the general circulation pattern suggested by averaging multiannual observations. Nutrient and particle distributions were influenced by the interactions of the shelf current with the rings. Where the cyclonic and anticyclonic eddies directed flow off the shelf, particles were transported off the shelf. Additionally, particles in the bottom nepheloid layer were transported off the shelf in the shoreward limb of the cyclone, even though currents in this limb were directed along the isobaths. Nutrient concentrations, hence nutrient fluxes, were generally low in near-surface waters every-where in the study area. At mid-depth and in near-bottom waters, nutrient fluxes were highest near the cyclone because of higher current speeds in this feature and higher nutrient concentrations at depth.

Les caracteristiques geochimiques des sediments adjacents a trois plates-formes de production (par 22 a 150, d'eau) dans le nord-ouest du golfe du Mexique ont ete determinees a partir de la presence de l'ouvrage, de la quantite et du type de materiaux liberes par l'ouvrage, et du contexte hydrographique local. Les sediments proches des plates-formes ( 80 m), les concentrations des metaux a l'etat de traces dans les sediments n'ont pas varie pendant des annees. Il s'est avere que quelques metaux (Pb, Cd) se sont constamment accumules dans les sediments depuis la mise a l'eau de la plate-forme.

A narrow band of high Chl a (23.1 ug liter-1) was observed at a salinity front in the western Mediterranean Sea in late November 1987. The biomass peak was found deep in the photic zone, at 54 m, in a region of low light. A single diatom species, Thalassiosira partheneia Schrader in gelationous colonies, represented 98% of the total phytoplankton biomass in the layer and achieved abundance. Although lack of temporal sampling precludes precise determination of the processes responsible, the high biomass accumulation and dominance by this species was likely due to its preference for low light coupled with turbulence-induced high nutrient levels. Interleaving patterns in the temperature, salinity, and nutrient profiles suggest increased horizontal advection at the front. High shear at the boundaries of the interleavings might confine the biomass to a thin band, as well as generate turbulence to mix nutrients in from surrounding layers. Alternatively, stabilization of the water column following a brief, pulsed upwelling event could have reduced dispersion of the biomass, thereby confining it to the thin layer we observed. Keywords: Ocean environments; Phytoplankton; Chemical oceanography; Ocean currents.

Diagnosis of a hyper- or hypocoagulable state has been very difficult. The first attempt to solve this problem was the method of endogenous thrombin potential (ETP) by Hemker. In ETP, activators and a chromogenic substrate are added to diluted plasma samples and the thrombin generation is measured. By analysis of acquired data, three characteristics of ETP are seen: lag phase, peak thrombin, and velocity index. ETP is not suited for exact determination of maximum activated thrombin. Therefore, a new method was developed: the thrombin generation assay (THROGA). With the use of THROGA, the maximum generated thrombin in a blood or plasma sample can be measured easily. The background of the method is the addition of a certain amount of recombinant hirudin (r-hirudin) to the blood or plasma sample. After activation, the generated thrombin is bound quantitatively and neutralized by r-hirudin so that at the end of the activation phase the amount of generated thrombin can be determined easily and exactly by measurement of residual r-hirudin in the sample.

At this time no practical laboratory method for the measurement of the current functional state of blood platelets is available. A new innovative platelet adhesion assay (PADA) is described here. With only a short time requirement and minimal equipment, the PADA provides quantitative measurements of platelet adhesiveness. Only 0.5 mL of freshly drawn citrated whole blood is needed, to which special polymer particles are added. A defined shear grade is induced by a short period of shaking the sample. Proteins of the blood sample, especially fibrinogen, and thereafter also activated platelets, bind to the specific polymer surface. Following platelet counts both in the sample and in a control (blood without particles), the adhesion index (AI) is calculated as a quantitative measure of platelet adhesiveness. In healthy volunteers, a mean AI of 52+/-12 was measured. AI was shown to be nearly independent of the number of platelets in the sample (100 to 350 k/ microL), the hematocrit (44 to 25%), and the fibrinogen content (1.5 to 5 g/L). Age of the volunteers had only a minor influence on the AI. PADA was shown to be a simple reliable laboratory method for the detection of disturbed platelet function. The test requires low analytical efforts compared with other diagnostic platelet function tests.

Platelet ADhesion Assay (PADA) is a POCT capable method for quantitative determination of platelet adhesiveness. Using special polymer particles and test conditions adjusted to the physiologic conditions, the current functional state of blood platelets is determined directly from a whole blood sample. Within a short time, using little technical equipment and small sample volume, a therapeutic drug monitoring of GP IIb/IIIa and ADP receptor antagonists is possible, too. Whereas in healthy volunteers dose/effect curves of GP IIb/IIIa antagonists vary only slightly, in thrombopilic patients there are big variations. Differences in efficacy up to drug resistance may occur also in use of the ADP receptor antagonist clopidogrel. A therapeutic drug monitoring of GP IIb/IIIa- and ADP receptor antagonist therapy is essential and becomes feasible using PADA, also as long-term drug monitoring of ADP receptor antagonists and detection of drug resistance. Additionally, an individual ex vivo dose estimation for GP IIb/IIIa antagonists is possible. PADA allows diagnostics of pathological platelet function in thrombophilic patients as well as long-term therapeutic drug monitoring due to its simple handling.

Our top-level goal is to improve the length of baselines that RTK-GPS 3-D positioning at the several-centimeter level can be done in the marine environment. Our other top goal is to improve the science of sediment classification through backscattered acoustic data, and provide methods that can be taken operational.