Prenatal diagnosis of chondroectodermal dysplasia with fetoscopy

Chondroectodermal dysplasia (Ellis-van Creveld syndrome) has previously been diagnosed prenatally only once, using fetoscopy. We report on two consecutive pregnancies in a woman at risk of having a child with the syndrome during which fetoscopic visualization was performed. Ellis-van Creveld syndrome was diagnosed prenatally in one instance, while it could be excluded in the other one. Non-invasive prenatal diagnosis of the syndrome is discussed.     

Effectiveness of short-term knowledge communication on Baltic Sea marine genetic biodiversity to public managers

The aim of this study is to assess the impact of two forms of short-term knowledge communication—lectures and group deliberations—on public managers’ policy beliefs regarding genetic biodiversity in the Baltic Sea. Genetic biodiversity is a key component of biological variation, but despite scientific knowledge and far-reaching political goals, genetic biodiversity remains neglected in marine management. Previous research highlights lack of knowledge among managers as one explanation to the implementation deficit. This multidisciplinary study builds on the identified need for an improved knowledge transfer between science and ongoing management. A basic knowledge package on genetic biodiversity in the Baltic Sea was presented as either a lecture or a deliberative group discussion to two separate samples of public managers who are involved in Baltic Sea and other biodiversity management at the regional level in Sweden. The empirical findings show that the communicated information has an impact on the public managers’ beliefs on genetic biodiversity of the Baltic Sea. Lectures seem more efficient to transfer knowledge on this theme. Those who received information through a lecture strengthen their confidence in area protection as a management tool to conserve genetic diversity. They were also more convinced of the obligation of authorities at national and regional level to take on larger responsibility for genetic conservation than those managers who participated in a deliberative discussion.

     

NOx reburning in oxy-fuel combustion: A comparison between solid and gaseous fuels

In the development of oxy-fuel combustion, reburning of nitrogen oxides, recycled with the flue gases, has been investigated for primary NO_x control. Reduction of between 50 and 80% of the recycled nitrogen oxides has been measured. The present work evaluates the performance of gaseous and solid fuels as agents for reduction of nitrogen oxides by comparing experimental and modelling work performed at Chalmers University of Technology with different fuels. It is shown that the reduction is similar during propane and lignite firing, but that the lignite has slightly higher reduction efficiency. Differences in combustion temperature and heterogeneous effects are possible explanations.     

Reproductive status, blood chemistry, gill histology and growth of perch (Perca fluviatilis) in three acidic lakes

Perch (Perca fluviatilis L.) were sampled soon after spawning in three small acidic lakes (pH 4.3-6.1, Al(lab) 5-106 microg litre(-1), Ca2+ 0.01-0.08 mmol litre(-1)) and in one circumneutral lake (pH 5.9-6.4, Al(lab) 4-12 microg litre(-1), Ca2+ 0.06-0.07 mmol litre(-1)) in southern Finland. Due to the delayed spawning of perch in the acidic lakes, sampling in those lakes was performed later than in the reference lake. In spite of that, the gonadosomatic index (GSI) of males in all the acidic lakes was significantly greater than in the reference lake. Of the two lakes with similar low water pH, the effects on reproduction were more prominent in the lake with higher water Al content. The plasma Ca2+ concentrations of females in the acidic lakes were significantly smaller than in the females of the reference lake. The low female:male plasma Ca2+ ratio (1.0-1.32) depicted delay of spawning. Stress in perch in acidic water was also seen in elevated blood haematocrit values, especially in females. On the other hand, a low plasma Cl- level, a common response to acidic water in salmonids, was not detected in perch in the most acidic lakes. The amount of Al accumulated in the gill epithelium was highest in the most acidified lake with high Al concentration, but was also pronounced in a lake with low pH and low Al concentration.     

Ozone exposure triggers the emission of herbivore-induced plant volatiles, but does not disturb tritrophic signalling

We evaluated the similarities between ozone-induced and mite-induced emission of volatile organic compounds (VOCs) from lima beans, and tested the response of the natural enemies of herbivores to these emissions using trophic system of two-spotted spider mites and predatory mites. The acute ozone-exposure and spider mite-infestation induced the emission of two homoterpenes, (E)-4,8-dimethyl-1,3,7-nonatriene and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, and (Z)-3-hexenyl acetate. Only plants with spider mite-infestation emitted the monoterpene (E)-beta-ocimene. Predatory mites were equally attracted to ozone-exposed and unexposed plants, but discriminated between spider mite-infested and uninfested plants, when both were exposed to ozone. The similarities between ozone and herbivore-induced VOCs suggest that plant defence against phytotoxic ozone and the production of VOCs for attraction of the natural enemies of herbivores may have adaptive coevolution. However, the expected elevated ozone concentrations in future may not disturb tritrophic signalling, unless herbivore-induced VOCs are lost in the process of aerosol formation.     

Contents and origin of polychlorinated diphenyl ethers (PCDE) in salmon from the Baltic Sea, Lake Saimaa and the Tenojoki river in Finland

The presence of 26 congeners of polychlorinated diphenyl ethers (PCDEs) was investigated in salmon from three locations in Finland. In addition to salmon, one chlorophenol wood preservative (Ky-5) and one fly ash sample were analyzed for PCDEs. Concentrations of PCDE congeners in salmon muscle measured by high resolution gas chromatography/low resolution mass spectrometry ranged from < 0.02 to 2.4 ng/g fresh weight. The major components of tetra- to octachlorinated PCDEs in salmon were one TeCDE (22′44′-), two PeCDEs (22′44′5- and 23′44′5-) and three HxCDEs (22′44′56′-, 22′44′55′- and 22′344′5-). The Baltic salmon caught from the Simojoki River had higher levels of PCDEs than the Atlantic salmon from the Tenojoki River or salmon from Lake Saimaa in South-Finland. Same PCDE congeners which were abundant in the wood preservative were also detected in salmon, whereas PCDE congeners in the fly ash were different from those in salmon or in Ky-5.     

Temporal and spatial variation in the growth rates of Baltic herring (<Emphasis Type="Italic">Clupea harengus membras</Emphasis> L.) larvae during summer

It has been suggested that larval survival determines the year-class strength in most marine fish species. During their growth and development, the ability of the larvae to catch prey and avoid predation will increase. However, the factors affecting short-term changes in the growth of Baltic Sea herring have been little studied in the field. We collected Baltic herring (Clupea harengus membras L.) larvae from five different towing areas in the Archipelago Sea (SW Finland) during May and June 1989, right after the main spawning season. Twenty thousand two hundred and ten larvae were analysed and the area-specific growth rate (i.e. increase in standard length) was estimated by tracing the larval cohorts from the length-frequency data. This represents the first Baltic herring study with daily sampling during a long study period. The growth rate was related to environmental factors, such as temperature, number of zooplankters, and wind speed and direction. Large variation in larval growth rate occurred between areas: lowest and highest growth rates were 0.18 and 0.52 mm·day^-1. Temperature was an important variable controlling larval-fish growth rate. An increase of one 1°C in average water temperature corresponded to an increase in growth rate of 0.043 mm·day^-1. This may have been caused either by a direct temperature effect (changes in metabolic rate) or by the indirect effect of changes in food availability. We also found the densest herring populations in the areas with highest average water temperature. However, temperature and larval growth rate both increased towards the inner archipelago.     

Time-Varying Parameter Analysis of the Baltic Sea Freshwater Runoffs

The Baltic Sea runoff events during 1970–2000 were analysed with non-linear estimation in order to find potential stability and time-varying (non-constancy) properties of time series parameters. In the Baltic Sea area, the wintertime rainfall is expected to increase, especially in the northern parts of the watershed; furthermore, seasonality is expected to decrease, i.e. the runoffs will become more evenly distributed over seasons, mainly by decreasing springtime peaks. We found a general increase in runoffs over the time period studied that consisted of a level shift upwards during the early 1980s. The runoffs considerably resulted from inputs in the months of April to June (which points to the significance of winter precipitation) and are biased to northern parts of the catchment. Our results suggest that this is connected with snow and ice melting in the northern areas of the watershed, especially in the subarctic catchment area of the Neva River (the area includes, for example, three of the four biggest lakes in Europe, Lake Ladoga, Lake Onega and Lake Saimaa, which are annually covered by ice). The yearly variation in runoff is significantly stabilised by large N–S extension of the watersheds of these lakes. The results are generally in accordance with the presented climatic expectations; however, decreasing seasonality was not obvious in the series yet. However, we found potential implications of system change towards decreased seasonality. By better understanding of ongoing processes in the sea, the results can give us an opportunity to better evaluate the system control, predicted areal consequences and ecosystem effects of the climate change. The analysis proved to be a sensitive tool for studying climatic variation in a relatively small area and over a short time span.