Prenatal diagnosis of free sialic acid storage disorders (SASD)

Free sialic acid storage disorders, Salla disease (SD) and Infantile sialic acid storage disease (ISSD), are lysosomal storage diseases due to impaired function of a sialic acid transporter, sialin, at the lysosomal membrane. Several mutations of the sialin gene, SLC17A5, are known, leading either to the severe neonatal/infantile disease or to the milder, adult-type developmental disorder, Salla disease. Free sialic acid accumulation in lysosomes causes increased tissue concentration and consequently elevated urinary excretion. Prenatal diagnosis of SASD is possible either by determination of free sialic acid concentration or by mutation analysis of the SLC17A5 gene in fetal specimen, in chorionic villus biopsy particularly. Both techniques have been successfully applied in several cases, sialic acid assay more often in ISSD cases but mutation analysis preferentially in SD. Sialic acid assay of amniotic fluid supernatant or cultured amniotic fluid cells may give erroneous results and should not be used for prenatal diagnosis of these disorders. The present comments are mainly based on our experience of prenatal diagnosis of SD in Finnish families. A founder mutation in SLC17A5 gene, 115C-> T, represents 95% of the disease alleles in the Finnish SD patients, which provides a unique possibility to apply mutation analysis. Therefore, molecular studies have successfully been used in 17 families since the identification of the gene and the characterization of the SD mutations. Earlier, eight prenatal studies were performed by measuring the free sialic acid concentration in chorionic villus samples. Copyright © 2006 John Wiley & Sons, Ltd.     

Phosphorus removal in a wetland constructed on former arable land

Phosphorus in surface runoff water may cause eutrophication of recipient water. This study clarifies the mechanisms of P removal in the wetland of Hovi, Finland, constructed on arable land in 1998. Before the construction, the surface soil (removed in the construction) and subsoil (the current wetland bottom) were analyzed for Al and Fe oxides (Al(ox) and Fe(ox)) reactive in P sorption, and for the distribution of P between various pools as well as for P exchange properties. Retention of P from runoff water within the wetland was studied from 1999 to 2001 in situ and factors affecting the P removal (O2 availability and P concentration in water) were investigated in a laboratory microcosm. The processes taking place in the wetland diminished by 68% the total P load and by 49% the dissolved reactive P load. Desorption-sorption tests indicated that without removal of the surface soil, there would have been a risk of the wetland being a source of P, since the equilibrium P concentration of the soil removed was high compared with the mean P concentration of the inflowing water. The subsoil contained less P and high amounts of reactive oxides, which could bind P. Evidently, the P sorption by Al(ox) played an important role in a first phase removal of P, since the wetland retained P efficiently even under anoxic conditions, where Fe tends to be reduced. Fine-textured, mineral soil on the bottom of the wetland (subsoil of the former arable land) seemed to be very efficient in retaining P from agricultural runoff.     

Production and characterization of bioaerosols for model validation in spacecraft environment

This study aimed to evaluate the suitability of two bioaerosol generation systems(dry and wet generation) for the aerosolization of microorganisms isolated from the International Space Station, and to calibrate the produced bioaerosols to fulfill the requirements of computational fluid dynamics model(CFD) validation. Concentration, stability, size distribution, agglomeration of generated bioaerosol and deposition of bioaerosols were analyzed. In addition, the dispersion of non-viable particles in the air was studied.Experiments proved that wet generation from microbial suspensions could be used for the production of well-calibrated and stabile bioaerosols for model validation. For the simulation of the natural release of fungal spores, a dry generation method should be used. This study showed that the used CFD model simulated the spread of non-viable particles fairly well. The mathematical deposition model by Lai and Nazaroff could be used to estimate the deposition velocities of bioaerosols on surfaces, although it somewhat underestimated the measured deposition velocities.     

Groundwater dependent ecosystems. Part I: Hydroecological status and trends

Groundwater dependent ecosystems (GDEs) include valuable ecosystems such as springs, wetlands, rivers, lakes and lagoons. The protection of these systems and services they provide is highlighted by international agreements, i.e. Ramsar convention on wetlands, and regional legislation, i.e. the European Water Framework Directive. Groundwater provides water, nutrients and a relatively stable temperature. However, the role of groundwater in surface ecosystems is not fully understood. The ecosystem can depend on groundwater directly or indirectly, and the reliance can be continuous, seasonal or occasional. This has implications for the vulnerability of ecosystems, as some may be easily affected by external pressure. Conceptual models and quantitative assessments of how groundwater interacts with the environment are needed. GDEs are also threatened by different land use activities and climate change. Hence, we need to understand how GDEs are affected by changes in groundwater quantity and quality, as severe groundwater changes have been observed in many regions. This study examines key aspects of GDEs (hydrogeology, geochemistry and biodiversity) in order to improve conceptual understanding of the role of groundwater in such ecosystems. The status and baseline of different types of GDEs are discussed, with particular emphasis on past evidence of environmental change and potential thresholds and threats in GDEs in various parts of Europe with different land use, climate and geology.     

Monitoring birds of prey in Finland: a summary of methods, trends, and statistical power

In Finland, Comprehensive Surveys to monitor numbers and productivity of four endangered species of birds of prey were started in the early 1970s. In 1982, the Ringing Center launched the Raptor Grid, a nationwide monitoring program for all other bird-of-prey species based on 10 x 10 km study plots of the Finnish National Grid. The annual total of study plots surveyed by voluntary raptor ringers has averaged 120. Since 1986, additional information on breeding performance has been collected using the Raptor Questionnaire. In 2006, more than 44 262 potential nest sites of birds of prey were inspected, and 12 963 occupied territories, including 8149 active nests, were found and reported by ringers. The population trend during 1982-2006 has been significantly negative in six species and positive or neutral in 18 species. Statistical power of the time series of numbers and productivity has been adequate for all species except the microtine specialists.     

Residential Indoor,Outdoor, and Workplace Concentrations of Carbonyl Compounds: Relationships with Personal Exposure Concentrations and Correlation with Sources

Abstract

Personal 48-hr exposures of 15 randomly selected participants as well as microenvironment concentrations in each participant’s residence and workplace were measured for 16 carbonyl compounds during summer–fall 1997 as a part of the Air Pollution Exposure Distributions within Adult Urban Populations in Europe (EXPOLIS) study in Helsinki, Finland. When formaldehyde and acetaldehyde were excluded, geometric mean ambient air concentrations outside each participant’s residence were less than 1 ppb for all target compounds. Geometric mean residential indoor concentrations of carbonyls were systematically higher than geometric mean personal exposures and indoor workplace concentrations. Additionally, residential indoor/outdoor ratios indicated substantial indoor sources for most target compounds. Carbonyls in residential indoor air correlated significantly, suggesting similar mechanisms of entry into indoor environments. Overall, this study demonstrated the important role of non-traffic-related emissions in the personal exposures of participants in Helsinki and that comprehensive apportionment of population risk to air toxics should include exposure concentrations derived from product emissions and chemical formation in indoor air.     

Status and trends of circumpolar peregrine falcon and gyrfalcon populations

Ambio - The peregrine falcon (Falco peregrinus) and the gyrfalcon (Falco rusticolus) are top avian predators of Arctic ecosystems. Although existing monitoring efforts are well established for both...     

Bright moonlight triggers natal dispersal departures

Upon leaving their natal area, dispersers are confronted with unknown terrains. Species-specific perceptual ranges (i.e. the maximum distance from which an individual can perceive landscape features) play a crucial role in spatial movement decisions during such wanderings. In nocturnal animals that rely on vision, perceptual range is dramatically enhanced during moonlight, compared to moonless conditions. This increase of the perceptual range is an overlooked element that may be responsible for the successful crossing of unfamiliar areas during dispersal. The information gathered from 143 radio-tagged eagle owl Bubo bubo juveniles in Spain, Finland and Switzerland shows that, although the decision to initiate dispersal is mainly an endogenous phenomenon determined by the attainment of a given age (～6 months), dispersers leave their birthplace primarily under the best light conditions at night, i.e. when most of the lunar disc is illuminated. This sheds new light into the mechanisms that may trigger dispersal from parental territory.     

The process of burnout in white‐collar and blue‐collar jobs: eight‐year prospective study of exhaustion

This study tested three contrasting theories about the sequential process of the three dimensions of burnout (i.e., exhaustion, cynicism and professional efficacy) as measured by the Maslach Burnout Inventory—General Survey (MBI‐GS). The causal order of the burnout components was investigated by including job stressors as antecedents of burnout in structural equation models (LISREL). The predictive effect of exhaustion on burnout dimensions eight years later was also investigated. The longitudinal models were then tested in two occupational subgroups. The participants were 713 Finnish employees (415 white‐collar and 298 blue‐collar workers) from an international industry enterprise. The best fitting model of the associations between the three burnout dimensions was obtained by a path model where exhaustion predicted cynicism, and cynicism in turn predicted lack of professional efficacy. The symptoms of exhaustion were persistent over time. There were no differences between the two occupational groups in the process of burnout. Also the work‐related antecedents of burnout (job stressors) were very similar in both groups. Copyright © 2002 John Wiley & Sons, Ltd.     

Fluxes of methane,carbon dioxide and nitrous oxide in boreal lakes and potential anthropogenic effects on the aquatic greenhouse gas emissions

We have examined how some major catchment disturbances may affect the aquatic greenhouse gas fluxes in the boreal zone, using gas flux data from studies made in 1994-1999 in the pelagic regions of seven lakes and two reservoirs in Finland. The highest pelagic seasonal average methane (CH(4)) emissions were up to 12 mmol x m(-2) x d(-1) from eutrophied lakes with agricultural catchments. Nutrient loading increases autochthonous primary production in lakes, promoting oxygen consumption and anaerobic decomposition in the sediments and this can lead to increased CH(4) release from lakes to the atmosphere. The carbon dioxide (CO(2)) fluxes were higher from reservoirs and lakes whose catchment areas were rich in peatlands or managed forests, and from eutrophied lakes in comparison to oligotrophic and mesotrophic sites. However, all these sites were net sources of CO(2) to the atmosphere. The pelagic CH(4) emissions were generally lower than those from the littoral zone. The fluxes of nitrous oxide (N(2)O) were negligible in the pelagic regions, apparently due to low nitrate inputs and/or low nitrification activity. However, the littoral zone, acting as a buffer for leached nitrogen, did release N(2)O. Anthropogenic disturbances of boreal lakes, such as increasing eutrophication, can change the aquatic greenhouse gas balance, but also the gas exchange in the littoral zone should be included in any assessment of the overall effect. It seems that autochthonous and allochthonous carbon sources, which contribute to the CH(4) and CO(2) production in lakes, also have importance in the greenhouse gas emissions from reservoirs.