Levels of selected individual polychlorinated biphenyls in different tissues of harbour seals (phoca vitulina) from the Southern coast of Norway

Concentrations of individual polychlorinated biphenyls (PCBs) were determined in blubber, liver, kidney and brain tissues of 10 male harbour seals (Phoca vitulina) of different ages. The animals were found dead or dying on the southern coast of Norway in 1988 during the morbilli virus epizootic. Twenty-three PCB congeners were investigated in all tissues by capillary gas chromatography with electron capture detection and comparison with standards of the respective congeners (IUPAC numbers 28, 52, 74, 99, 101, 105, 110, 114, 118, 128, 138, 141, 149, 153, 156, 157, 170, 180, 183, 187, 194, 206 and 209). In addition, three toxic coplanar congeners (IUPAC numbers 77, 126 and 169) were investigated in the blubber samples. Total PCB (sum of the determined congeners) in kidney (12-60 nmol g(-1)), liver (12-90 nmol g(-1)) and blubber (10-79 nmol g(-1)) were similar on extractable lipid basis, while total PCB in brain lipid was about 1/10 (1.6-12 nmol g(-1)). The absolute concentrations of the individual congeners in brain lipid correlated poorly with the respective concentrations in each of the other tissues, while the individual congener concentrations in the lipid fractions of kidney, liver and blubber tended to correlate with each other. The relative concentrations of the sum of the most persistent congeners (PCB-99, -128, -138, -153, -170, -180, -187 and -194) correlated in all tissues, and an increase of the relative concentrations of these congeners, most distinct in blubber, with higher carcass weight, was shown. Also, total PCB in blubber correlated with carcass weight. When comparing the relative concentration patterns of individual congeners (per cent of total) in the four tissues, six congeners differed significantly between tissues, and the relative brain concentrations showed most deviation from the other tissues. The concentration of the coplanar PCBs was 1 : 1000-1 : 1000 of the total PCB concentration. The results demonstrate a lower accumulation together with a different concentration pattern in the brain as compared to other tissues.     

Bioremediation of a weathered and a recently oil-contaminated soils from Brazil: a comparison study

The facility with which hydrocarbons can be removed from soils varies inversely with aging of soil samples as a result of weathering. Weathering refers to the result of biological, chemical and physical processes that can affect the type of hydrocarbons that remain in a soil. These processes enhance the sorption of hydrophobic organic contaminants (HOCs) to the soil matrix, decreasing the rate and extent of biodegradation. Additionally, pollutant compounds in high concentrations can more easily affect the microbial population of a recently contaminated soil than in a weathered one, leading to inhibition of the biodegradation process. The present work aimed at comparing the biodegradation efficiencies obtained in a recently oil-contaminated soil (spiked one) from Brazil and an weathered one, contaminated for four years, after the application of bioaugmentation and biostimulation techniques. Both soils were contaminated with 5.4% of total petroleum hydrocarbons (TPHs) and the highest biodegradation efficiency (7.4%) was reached for the weathered contaminated soil. It could be concluded that the low biodegradation efficiencies reached for all conditions tested reflect the treatment difficulty of a weathered soil contaminated with a high crude oil concentration. Moreover, both soils (weathered and recently contaminated) submitted to bioaugmentation and biostimulation techniques presented biodegradation efficiencies approximately twice as higher as the ones without the aforementioned treatment (natural attenuation).     

Prenatal diagnosis of Bruck syndrome

Bruck syndrome is an autosomal recessive connective tissue disorder combining features of osteogenesis imperfecta and arthrogryposis multiplex congenita. There are only few reports describing this rare syndrome of multiple fractures and joint contractures that is thought to be a subtype of osteogenesis imperfecta. We report the first case of prenatal diagnosis of this syndrome in a fetus at 23 weeks of gestation. Ultrasound findings included brachycephaly, retrognathia marked shortening and bowing of both femurs, bilateral fixed flexion of the elbows, bilateral fixed extension of the wrists and partially fixed flexion of the knees. The parents opted for termination of pregnancy. Macroscopic and radiologic examination of the aborted fetus confirmed the prenatal diagnosis, whereas morphological studies of the bone tissue found no hard evidence of osteogenesis imperfecta, probably due to the early stage of pregnancy and the heterogeneity of the syndrome itself. Copyright © 2005 John Wiley & Sons, Ltd.     

Critical Reconsideration of Phase Space Embedding and Local Non-Parametric Prediction of Ozone Time Series

Phase space prediction is a feature selection method which triesto exploit non-linear dynamics of an underlying system. We describe and offer a critical reconsideration of this approach,discuss questions of whether non-linear methods are justified by the data, and apply them to ozone time series from single locations. Our main objectives are to obtain air quality forecasts in order to provide public health warnings and to provide an insight into the dynamics of the underlying system.Interestingly, comparable linear data sets (surrogates)have very similar structure and give similar predictionaccuracy to that of the ozone data. In this instance theredoes not appear to be any advantage to applying the phasespace approach to univariate time series.     

The improvement of strength and microstructural properties of fly ash-based geopolymer by adding elemental aluminum powder

Journal of Material Cycles and Waste Management - In this study, 1, 2, and 3% micronized aluminum powder were used by replacing with fly ash to improve the properties of F class fly ash-based...     

(3R,4S)-Methyl-3-heptanol,the trail pheromone of the ant Leptogenys diminuta

We wish to thank Prof. V. Schurig (Tübingen) for lending us the columns for preliminary studies, and Prof. K. Mori (Tokyo), N. Frighetto and R. T. S. Frighetto (Erlangen) for optically active samples of 4-methyl-3-heptanol. This work was supported by the Deutsche Forschungsgemeinschaft.     

Phenolic xenoestrogens in surface water, sediments, and sewage sludge from Baden-Württemberg, south-west Germany.

Nine structurally different phenolic chemicals, which have been reported to mimic estrogen effects, were determined in various aquatic environmental compartments. Twenty-three water samples from five streams and rivers showed levels up to 458 ng/l for 4-nonylphenol (4NP), 189 ng/l for 4-t-octylphenol (4tOP), 272 ng/l for bisphenol A (BPA) and 47 ng/l for 2-hydroxybiphenyl (2OHBiP). Elevated levels of these compounds in a stream with a high load of effluents of sewage treatment plants (STPs), compared to a brook free of sewage, identified STPs as major sources. With a similar order, 4NP (10-259 micrograms/kg dry matter), 4tOP (< 0.5-8 micrograms/kg), BPA (< 0.5-15 micrograms/kg), and 2OHBiP (2-69 micrograms/kg) were also detected regularly in riverine sediment (n = 11). Levels in sewage sludge were one order of magnitude higher than in sediments. 4-Hydroxybiphenyl and 4-chloro-3-methylphenol were found predominantly in sludge and sediment in the lower ppb range.     

No evidence for the work-conflict hypothesis in the eusocial naked mole-rat (Heterocephalus glaber )

The work-conflict hypothesis (Reeve 1992) postulates that in eusocial naked mole-rat (Heterocephalus glaber) colonies there is potential conflict between the breeding female and her non-breeding colony mates over how much aid they provide in support of her reproduction. Non-breeders may withhold aid either because they are hopeful reproductives and/or because they have less to gain in terms of inclusive fitness. Breeding females should, therefore, preferentially direct aggression in the form of shoving (prolonged pushes usually involving nose-to-nose contact) towards large (hopeful reproductives) and less related non-breeders to incite them to provide aid. This study tested the following predictions of the work-conflict hypotheses. (1) There is kin bias in the shove rate of breeding females and work rates of non-breeders; (2) Shoving activates work in non-breeders. We found no evidence to suggest that the breeding female shove rate and the amount of colony maintenance activities performed by non-breeders is influenced by relatedness. Body size was a better predictor of work rate and shove rate; large animals were shoved more and worked less. Furthermore, shoving did not affect the work rate of non-breeders and rarely incited activity in inactive mole-rats. Individual mole-rats were also more likely to be shoved when already active than when resting in the nest. These results suggest that shoving by the breeding female may have functions other than the incitement of activity, such as the reproductive suppression of non-breeders. Received: 17 January 1996 / Accepted after revision: 21 September 1996