Juvenile life stages of the brown alga Fucus serratus L. are more sensitive to combined stress from high copper concentration and temperature than adults

The combined effects of exposure to copper and temperature were investigated in adult specimens and germlings of the canopy-forming brown alga Fucus serratus. A matrix of four temperatures, 6, 12, 17 and 22 °C, and three concentrations of copper, 0, 100 and 1,000 nM total copper were used. Measured endpoints were growth rate, chlorophyll fluorescence parameters and for germlings also survival. The growth rate of adult specimens of F. serratus changed with increasing temperature. Growth tended to be negatively affected by high concentrations of copper when exposed to heat (22 °C) though not significantly so. The photosynthetic performance (i.e., chlorophyll fluorescence parameters: F _v/F _m, maximum electron transport rate (ETR_max) and maximum non-photosynthetic quenching (NPQ_max) of adults was largely unaffected by both copper and temperature. Germling survival, growth rate and chlorophyll fluorescence parameters were affected by the combination of copper concentration and temperature. Increasing temperature led to reduced survival, increased rhizoid growth and higher F _v/F _m and ETR_max, whereas high copper concentration had a negative effect on the latter three endpoints. The negative effect of high copper concentration was amplified by high temperature. We conclude that juveniles of F. serratus are more susceptible to environmental stressors than adult specimens and recommend therefore including early life stages when assessing the risk of exposure to toxic compounds. Considering the response of adult specimens only may lead to false conclusions regarding the ecological impact of environmental stress.     

Atmospheric methane at Zeppelin Station in Ny-Alesund: presentation and analysis of in situ measurements

In situ methane (CH(4)) measurement techniques and data from the Zeppelin Station in Ny-Alesund on Svalbard (N 78 degrees 54' E 11 degrees 53') on Mt. Zeppelin (475 m.a.s.l) are presented. The data span the time period from October 1998 to December 2003, though not continuously. The daily mean was calculated from 96 samples per day which are analysed by gas chromatography with flame ionisation detection. Details of the experimental methods and procedures are given. A harmonic function is fitted to the data with a constant trend and seasonal amplitude. The data are also presented in a regression plot showing the difference between the in situ measurements and flask measurements from the National Oceanic and Atmospheric Administration of the Climate Monitoring and Diagnostics Laboratory (NOAA/CMDL) in Boulder, Colorado (http://www.cmdl.noaa.gov/). The Zeppelin data show typical Arctic air characteristics with wintertime pollution episodes from Europe and Russia and a relatively calm summer state.     

Integration of Remote Sensed and In-situ Data in an Analysis of the Air Pollution Effects on Terrestrial Ecosystems in the Border Areas between Norway and Russia

Transboundary air pollution from industries in Nikel and Zapolyarnij has caused severe damage to the environment in Southern-Varanger in Norway and in Pechenga municipality in Russia. The work presented in this paper focuses on the integration of in-situ air pollution data with remote sensing based land cover maps. Land cover maps have been utilised to detect changes in the major land cover types within the area. The major change in the environment was the decrease of the sensitive lichen-dominated land cover types, and the increase of bilberry-dominated land cover types and finally the increase of the land cover types with the greatest air pollution stress (industrial barren, barren, and partly damaged vegetation, defoliated forests, lichen removal). A GIS based method for assessing the relationship of the remotely sensed land cover maps with the environmental condition parameters was developed and applied. By comparing the results from this analysis we observed that the land cover types with the greatest stress had the largest concentrations of SO₂ in the ground air layer, while the land cover types with minor damage (the remaining lichen-dominated vegetation) had rather low concentrations of sulphur dioxide in the ground air layer. The area of the land cover types with the greatest stress (industrial barren, barren and partly damaged vegetation) has increased in the period 1973–1988, and the degradation is carried out in a such manner that sensitive mountain and lichen vegetation formations have been transformed into a more barren-like environment. The increase in the emissions has also transferred the natural barrens which also consisted of some sparse vegetation into a complete barren with little vegetation left. Also the epilitic lichens and mosses on bare rocks and stones were also removed by the high concentrations of SO₂. The land cover types with minor damage (with the remaining lichen-dominated vegetation) had rather low concentrations of the contaminants (SO₂, Ni and S), while the partly damaged and damaged land cover types had the highest concentrations of the contaminants. An exception was the Ni and S concentrations found in class 11 Industrial barrens which were lower than expected. Associations between the degradation and the SO₂ concentration in the air were also documented. The conclusion from this analysis is that the in-situ data support the observations of damaged vegetation and industrial barrens imaged by the Landsat satellites, especially in the surroundings of Nikel and Zapolyarnij.     

Noninvasive prenatal screening for cystic fibrosis using circulating trophoblasts: Detection of the 50 most common disease-causing variants

Objectives

Cystic fibrosis (CF) is one of the most common severe autosomal recessive disorders. Prenatal or preconception CF screening is offered in some countries. A maternal blood sample in early pregnancy can provide circulating trophoblasts and offers a DNA source for genetic analysis of both the mother and the fetus. This study aimed to develop a cell-based noninvasive prenatal test (NIPT) to screen for the 50 most common CF variants.

Methods

Blood samples were collected from 30 pregnancies undergoing invasive diagnostics and circulating trophoblasts were harvested in 27. Cystic fibrosis testing was conducted using two different methods: by fragment length analysis and by our newly developed NGS-based CF analysis.

Results

In all 27 cases, cell-based NIPT provided a result using both methods in agreement with the invasive test result.

Conclusion

This study shows that cell-based NIPT for CF screening provides a reliable result without the need for partner- and proband samples.