Odoriferous compounds from the flowers of the conifers Picea abies,pinus sylvestris and Larix sibirica

A GC/MS analysis of the volatile constituents from the flowers of Norway Spruce, Picea abies, has been carried out. The volatile constituents of the female flowers were distinctly different from those of the male flowers and the twigs. Characteristic constituents are methyl and ethyl benzoate, methyl and ethyl salicylate, methyl and ethyl butanoate, borneol and bornyl acetate. In the scent from the male flowers we could only detect the same monoterpenes as in the twigs. In Larix sibirica methyl benzoate, methyl salicylate, borneol and bornyl acetate were detected in the female flowers and, in the female flowers of Pinus sylvestris, methyl salicylate was found.     

The influence of nitrate on the phosphorus flux to and from oxygen depleted lake sediments

Addition of nitrate to an oxygen depleted sediment leads to a stimulation of the mineralization process if a major part of the nitrate is dissimilatorily reduced. This may cause an increased release of phosphate from some sediments. Nitrate, however, maintains a high redox potential at the sediment surface and thus prevents a release of iron-bound phosphorus. These two counteracting effects of nitrate addition to sediment-water systems were demonstrated in laboratory experiments. A high supply of nitrate to a phosphorus-saturated sediment caused an increased release of phosphate and ammonium once the nitrate had been used up. However, from other sediments there was no or very little release of phosphate but an increased release of ammonium caused by high nitrate dissimilation, probably due to the very high capacity of these sediments to bind liberated phosphate or due to storage of phosphorus in an increased bacterial biomass. Phosphorus fractionation, before and after the experiments with the sediments, provided information on transfers to, from and within the sediments.     

Enzyme catalyzed hydrolysis of the diesters of cis- and trans-cyclohexanedicarboxylic acids

Summary Pig liver esterase (EC 3.1.1.1) catalyzed hydrolysis of the dimetrhy ester of meso-cis-1,2-cyclohexanedicarboxylic acid yielded the optically pure (1S,2R)-monoester. The corresponding diethyl ester yielded racemic monoester.The diethyl ester of racemic trans-1,2-cyclohexanedicarboxylic acid was kinetically resolved by partial hydrolysis with subtilisin (EC 3.4.21.14) or pig liver esterase. The (1R,2R)-monoester had an enantiomeric excess of 45% and was obtained in an enantiomerically pure form through recrystallisation. The remaining (1S,2S)-diester exhibited an enantiomeric excess of 83%. The nature of the ester function (methyl, ethyl, and propyl esters) had a great influence on the enantiomeric excess obtained and on the kinetic parameters.     

WHO ARE THE BENEFICIARIES?

Is it defensible that society spends money on medical or research projects intended to help people solve their fertility problems? Suppose that we want to answer this question from the point of view of a utilitarian cost-benefit analysis. The answer to the question then depends, of course, on how expensive these projects turn out to be, relative to the costs of other possible projects. But it depends also on how we assess the benefits of these projects. To whom do they accrue? Who are the beneficiaries of these projects?     

Eight new species of Hieracium sect. Tridentata (Asteraceae) from southern and northern Sweden

Eight new species of Hieracium sect. Tridentata, namely H. antrorsum, H. quercifolium, H. stenianum, H. vestrogothicum, and H. vetlandaënse are described from the Götaland region (southern Sweden), H. grothii from Norrbotten in the Norrland region (northeast Sweden), and H. sparsifolium var. suppansum Johanss. and H. adampliatum var. pilosius Ohlsén are raised to specific rank as H. suppansum and H. gothiciferum respectively.     

Seasonal dynamics of denitrification activity in two water meadows

Seasonal variation in denitrification activity was measured in twoflooded water meadows, one on peaty and one on sandy soil, over a three-yearperiod. Measurements were taken during flooded and drained periods, usingthe acetylene-blockage technique, and the rates were compared to massbalance estimates of nitrate removal in the percolating water.Denitrification activity was higher in sandy soil than in peaty soil. Higherwater infiltration rate and thereby higher nitrate load was considered to bethe cause of the higher denitrification in the sandy soil. Floodingsignificantly increased denitrification, and the rates were higher in autumnand winter than in spring. This was considered to be a result of highernitrogen concentration in inflowing stream water during winter. Annualdenitrification was estimated to 430–460 kg N ha^-1yr^-1 in the sandy soil meadow, and 220 kg N ha^-1yr^-1 in the peaty soil meadow. In the sandy soil there was alarge discrepancy between nitrate removal rates and denitrification rates,which can be explained by nitrification of ammonium released from the soil.In the peaty soil nitrate disappearance and denitrification correspondedfairly well.     

Water-blooming and toxin-producing cyanobacteria in Swedish fresh and bracish waters, 1981–1995

During the period 1981–1995 331 phytoplankton samples from 153stations in different parts of Sweden were analysed regardingspecies composition and possible toxicity. Toxins were indicated in156 samples which gives a percentage of 47. The toxicity wasconfirmed by mouse bioassay. All samples were collected fromwater-blooming lakes, mainly containing taxa belonging to thecyanobacterial genera Anabaena, Aphanizomenon, Microcystis and Planktothrix. In addition to informationabout occurrence of neuro- or hepatotoxins, knowledge about thedistribution of water-blooming lakes in the country was obtained aswell as about their predominating taxa. Microcystisaeruginosa, Anabaena flos-aquae and Aphanizomenonflos-aquae were the most frequently occurring taxa in the lakes.Among the taxa observed, nine different cyanobacterial species withcertainty produce toxins. Microcystis spp. most frequentlyproduced toxic blooms (only hepatotoxins). Anabaena spp.,however, caused the majority of waterblooms. The Anabaenaflos-aquae-group produced neurotoxins [incl. anatoxin-a(s)],neurotoxins + hepatotoxins or only hepatotoxins. Aphanizomenon flos-aquae was only recorded as toxin-producing inthree Swedish lakes, which may be compared with the conditions inFinland, where it was toxic in 36 bloom samples. Aspects are givenon toxicity versus lake acidification and trophic conditions, aswell as on health effects on animals and humanbeings.     

Pattern of functional extinctions in ecological networks with a variety of interaction types

There is a strong trend of declining populations in many species of both animals and plants. Dwindling numbers of species can eventually lead to their functional extinction. Functional, or ecological, extinction occurs when a species becomes too rare to fulfill its ecological, interactive role in the ecosystem, leading to true (numerical) extinction of other depending species. Recent theoretical work on food webs suggests that the frequency of functional extinction might be surprisingly high. However, little is known about the risk of functional species extinctions in networks with other types of interactions than trophic ones. Here, we explore the frequency of functional extinctions in model ecological networks having different proportions of antagonistic and mutualistic links. Furthermore, we investigate the topological relationship between functionally and numerically extinct species. We find that (1) the frequency of functional extinctions is higher in networks containing a mixture of antagonistic and mutualistic interactions than in networks with only one type of interaction, (2) increased mortality rate of species having both mutualistic and antagonistic links is more likely to lead to extinction of another species than to extinction of the species itself compared to species having only mutualistic or antagonistic links, and (3) trophic distance (shortest path) between functionally and numerically extinct species is, on average, longer than one, indicating the importance of indirect effects. These results generalize the findings of an earlier study on food webs, demonstrating the potential importance of functional extinction in a variety of ecological network types.     

Trends in Food Habits and Their Relation to Socioeconomic Status among Nordic Adolescents 2001/2002-2009/2010

Background

In the Nordic countries, substantial policy and intervention efforts have been made to increase adolescents'' consumption of fruit and vegetables and to reduce their intake of sweets and soft drinks. Some initiatives have been formulated in a Nordic collaboration and implemented at national level. In recent years, social inequalities in food habits have been attracted particular governmental interest and several initiatives addressing the socioeconomic gradient in food habits have been highlighted. However, few internationally published studies have evaluated how trends in adolescents'' food habits develop in the context of Nordic nutrition policy, or have compared differences between the Nordic countries.

Methods

The study was based on Danish, Finnish, Norwegian and Swedish cross-sectional data from the international Health Behaviour in School-Aged Children (HBSC) study, collected via three nationally representative and comparable questionnaire surveys in 2001/2002, 2005/2006 and 2009/2010. Food habits were identified by students'' consumption of fruit, vegetables, sweets and sugar sweetened soft drink. Socioeconomic status (SES) was measured with the Family Affluence Scale (FAS). Multilevel logistic regression was used to analyze the data.

Results

Trends in fruit consumption developed differently across countries, characterized by an increase in Denmark and Norway and more stable trends in Sweden and Finland. Vegetable consumption increased particularly in Denmark and to a lesser extent in Norway, whereas Sweden and Finland displayed stable trends. Decreased trends were observed for sweet and soft drink consumption and were similar in Norway, Sweden and Finland. Sweet consumption decreased across all survey years, whereas soft drink consumption decreased between 2001/2002–2005/2006 and was stable thereafter. Denmark displayed an increase between 2001/2002–2005/2006 followed by a similar decrease between 2005/2006–2009/2010 for both sweet and soft drink consumption. Socioeconomic inequalities in fruit and vegetable consumption were observed in all countries, with no cross-country differences, and no changes over time. Small but not significant cross-country variation was identified for SES inequalities in sweet consumption. Reduced SES inequalities were observed in Sweden between 2005/2006 and 2009/2010. SES was not associated with soft drink consumption in this study population, with the exception of Denmark for the survey year 2009/2010.

Conclusion

Different trends resulted in increased country differences in food habits during the time of observations. In survey year 2009/2010, Danish students reported a higher intake of fruit and vegetable consumption than their counterparts in the other Nordic countries. Finnish students reported the lowest frequency of sweets and soft drink consumption. Despite the positive dietary trends documented in the present study, the majority of Nordic adolescents are far from meeting national dietary recommendations. Our findings underline the need for more comprehensive initiatives targeting young people''s food habits as well as a more deliberate and focused action to close gaps in social inequalities that affect food choices.     

Comparison Between Elisa and Dye Test for Detection of Naturally Acquired Toxoplasma Gondii Antibodies in the Goat

Toxoplasma gondii IgG antibodies were measured in 212 goat sera, comparing the Sabin-Feldman dye-test and a three-layer sandwich enzyme-linked immunosorbent assay (ELISA). With 98 % concordance obtained between these 2 tests, the results are at the same paragon as for human sera. Accordingly, the ELISA sandwich procedure appears to be suitable for large-scale analysis of goat sera. The discordant 2 % were ELISA positive and dye-test negative. One possible explanation of the divergent titres is given using an immunized goat model.