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Knowledge of oil-induced impacts from the literature and experts were used to develop a Bayesian network to evaluate the biological consequences of an oil accident in the low-saline Gulf of Finland (GOF). Analysis was carried out for selected groups of organisms. Subnetworks were divided into subgroups according to a predicted response to oil exposure. Two scenario analyses are presented: the most probable and the worst-case accident. The impact of the most probable accident in the GOF is rather small. In most of the groups studied oil-induced long-term effects are evaluated to be minor at least from the perspective of the whole GOF. After the worst-case accident negative effects are more likely. The model predicts that the most vulnerable groups are auks and ducks. Amphipods, gulls and to a lesser extend littoral fishes and seals may show delayed recovery after an accident. Also annual plant species may be susceptible to oil-induced disturbances., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Increasing oil transportation and severe oil accidents in the past have led to the development of various sensitivity maps in different countries all over the world. Often, however, the areas presented on the maps are far too large to be safeguarded with the available oil combating equipment and prioritization is required to decide which areas must be safeguarded. While oil booms can be applied to safeguard populations from a drifting oil slick, decision making on the spatial allocation of oil combating capacity is extremely difficult due to the lack of time, resources and knowledge. Since the operational decision makers usually are not ecologists, a useful decision support tool including ecological knowledge must be readily comprehensible and easy to use. We present an index-based method that can be used to make decisions concerning which populations of natural organisms should primarily be safeguarded from a floating oil slick with oil booms. The indices take into account the relative exposure, mortality and recovery potential of populations, the conservation value of species and populations, and the effectiveness of oil booms to safeguard different species. The method has been implemented in a mapping software that can be used in the Gulf of Finland (Baltic Sea) for operational oil combating. It could also be utilized in other similar conservation decisions where species with varying vulnerability, conservational value, and benefits received from the management actions need to be prioritized.

Maritime traffic poses a major threat to marine ecosystems in the form of oil spills. The Gulf of Finland, the easternmost part of the Baltic Sea, has witnessed a rapid increase in oil transportation during the last 15 years. Should a spill occur, the negative ecological impacts may be reduced by oil combating, the effectiveness of which is, however, strongly dependent on prevailing environmental conditions and available technical resources. This poses increased uncertainty related to ecological consequences of future spills. We developed a probabilistic Bayesian network model that can be used to assess the effectiveness of different oil combating strategies in minimizing the negative effects of oil on six species living in the Gulf of Finland. The model can be used for creating different accident scenarios and assessing the performance of various oil combating actions under uncertainty, which enables its use as a supportive tool in decision-making. While the model is confined to the western Gulf of Finland, the methodology is adaptable to other marine areas facing similar risks and challenges related to oil spills., (Copyright © 2010 Elsevier B.V. All rights reserved.)

The present study tested the hypothesis that salmon cardiac peptide (sCP), a new member of the family of natriuretic peptides, has an important role in the regulation of fluid balance and cardiovascular function. Intra-arterial administration of sCP increased urine output in salmon. It had a diuretic effect in rat as well, but the potency was lower. sCP increased the sodium excretion in proportion to the increased urine flow. Blood pressure was not affected by sCP in either species. Acute volume expansion elevated the plasma level of sCP in salmon, and an acute transfer of salmon from fresh to sea water decreased the circulating sCP level. Cardiac immunoreactive sCP or sCP mRNA levels were not affected by transfer to sea water. These results indicate that sCP has an important physiological role in defending salmon against volume overload but that it does not appear to contribute to the short-term regulation of blood pressure. sCP provides an excellent model of the general mechanisms of regulation of the A-type (atrial) natriuretic peptide system.

Low temperature can be expected to increase the resistance to deformation of red blood cells, but the effect of such changes on microcirculatory perfusion are unknown. We therefore analysed resistance to flow through capillary-sized apertures for individual human red blood cells, by micropipette aspiration (approximately 3 microm aperture) and pore transit analysis (approximately 5 microm), as well as average resistance to flow of red cell suspension through multipore filters (5-microm pores). Over a range decreasing from 37 to 0 degrees C, rates of flow of single cells through the 3- and 5-microm apertures decreased monotonically by 2.5- to 3-fold. The changes were similar in magnitude to that expected for the viscosity of aqueous fluid (2.5-fold increase). Average flow resistance measured by bulk filtration also increased in line with viscosity of water, while tendency to block pores was not increased. Micropipette aspiration of small membrane tongues showed that membrane rigidity increased as temperature was lowered, but by a factor rather less than the viscosity. Cell volume also responded rapidly to change in temperature, with lower temperature being associated with swelling, although this effect was much reduced in plasma compared with saline buffer. We conclude that, although increased resistance to deformation of red cells may impair microcirculation at low temperature, there is no structural change likely to induce more dramatic occlusion of flow. Moreover, the effect is comparable in magnitude to the increase predicted for changes in plasma and blood viscosity.