Radiation effects in reindeer

With the present level of radiocesium contamination, direct radiation effects have been hypothesised

Radiobiologiska effekter på djur/renar av nuklidutsläpp från reaktorhavarier

Det som for oss biologer år intressant, det år dom medeltunga kårnorna som bildas. Man har nåstan tvåhundra slags atomer, nuklider som bildas, och de år nåstan alla radioaktiva. Det år den radioaktiviteten som påverkar djur och månniskor på olika sått. Ser man på vilka åmnen som finns i det hår området av periodiska systemet (masstal 80-150), så år det bara ett som normalt ingår i omsåttningen hos djur och det år jod. Men man har också cesium som liknar kalium och strontium som liknar kalcium och dårfor går in i djurens metabolism. De tre åmnena kommer då att få livsmedelshygienisk betydelse når de fororenar olika livsmedel. Jag skal emellertid uppehålla mig mera med de hår åmnena som strålkållor och alltså som potentiella skadliga åmnen for djuren

Radiocesium metabolism in reindeer

Abstract: Early in the era of atmospheric nuclear weapon tests, the reindeer was found to be an interesting animal concerning the transfer of environmental radioactive contaminants to man via the production of contaminated reindeer meat. The reason for the high transfer factors for some radionuclides is the feeding habits of the reindeer with a substantial intake of lichens, especially in the wintertime. One effect of the seasonal changes in feeding is also a considerable cyclic, seasonal variation in radiocesium content of soft tissues. The effective half-life of radiocesium was determined to about 30 days in an experiment where a herd of reindeer was moved form a high (>20 kBq/m2137Cs) to a low (<3 kBq/m2 137Cs) contamination area. The fractional transfer of 137Cs, during natural grazing, was determined to about 0.65 d/kg during wintertime on the low- contamination area and about 0.30 d/kg in summertime grazing in a more contaminated area. The radiation dose received by reindeers in Sweden after the Chernobyl accident was calculated to <200 mSv/a. The dose rate would be highest during the later part of winter but would not exceed 1 mSv/d

Economic Analysis of Using Renewable Wind Power System at a Signalized Intersection

The transportation industry consumes about 28% of the total energy consumed by all sectors in the United States. This paper proposes a renewable wind power system (RWPS) as an alternative power source for signalized traffic intersections. The proposed system can be mounted onto the existing transportation infrastructure to provide reliable green electricity. Large-scale implementation of such a system has the potential to dramatically change the role of the public right-of-way system from an energy consumer to an energy producer, which will reduce the transportation system operating costs and promote the development of greener roadways. This paper provides a framework to investigate the physical and economic feasibility of installing the proposed RWPS. Methodologies to conduct structural analysis, site selection, and economic analysis are developed and presented. A test intersection in Lincoln, Nebraska, is used to demonstrate the application of evaluation procedures. The proposed RWPS has two benefits: i) the power generated by the system can support the existing traffic signals and any excess power produced can be sold back to the power grid, and ii) it also provides a source of backup power in case of grid failures, increasing the reliability of traffic operations. The paper presents the methodology to ascertain the economic benefits of an RWPS for both the cases described above. The costs and benefits of providing a RWPS are stated in terms of dollar values. The decision to install a RWPS at a specific site can thus be made using a benefit-to-cost ratio. The case study shows the RWPS is economically feasible at the subject intersection in Lincoln, Nebraska. The results also show that installing an RWPS at intersections with frequent power supply failures would result in higher benefit-to-cost ratios. In the event of budget constraints, the methodology developed in this paper can be used to prioritize the investments based on the benefit-to-cost ratios for the prospective sites

Cats' internal exposure to selected brominated flame retardants and organochlorines correlated to house dust and cat food

Pet cats may be used as a biomarker for assessing exposures to organohalogen compounds (OHCs) adsorbed to household dust in home environments. This study explores two exposure routes of OHCs, ingestion of OHCs (i) via house dust and (ii) via cat food. House dust from 17 Swedish homes and serum from the participating families' pet cats were collected, and cat food was purchased matching the diet reported. Paired samples of cat serum, house dust, and cat food were analyzed for brominated flame retardants/natural products (polybrominated diphenyl ethers (PBDEs), decabromobiphenyl (BB-209), decabromodiphenyl ethane (DBDPE), 2,4,6-tribromophenol (2,4,6-TBP), OH-PBDEs) and organochlorines (polychlorinated biphenyls (PCBs), 1,1-bis(4,4'-dichlorodipheny1)-2,2,2-trichloroethane (4,4'-DDT), 1,1-bis(4,4'-dichlorodiphenyl)-2,2-dichloroethene (4,4'-DDE), hexachlorobenzene (HCB), pentachlorophenol (PCP)). Significant correlations were found between serum and dust samples from the living rooms for BDE-47 (p < 0.035), BDE-99 (p < 0.035), and BDE-153 (p < 0.039), from the adult's bedroom for BDE-99 < 0.019) and from all rooms for BDE-99 (p < 0.020) and BB-209 (p < 0.048). This is the first time a correlation between cat serum levels and household dust has been established, a finding that supports the hypothesis that dust is a significant exposure route for cats. Serum levels were also significantly correlated with concentrations found in cat food for 6-OH-BDE47 (p < 0.002), 2,4,6-TBP (p < 0.035), and BB-209 (p < 0.007). DBDPE was found in high concentrations in all dust (median 154 pmol/g) and food samples (median 0.7 pmol/ig lw) but was below detection in serum samples, suggesting low or no bioavailability for DBDPE in cats

Improved systematic tRNA gene annotation allows new insights into the evolution of mitochondrial tRNA structures and into the mechanisms of mitochondrial genome rearrangements

Transfer RNAs (tRNAs) are present in all types of cells as well as in organelles. tRNAs of animal mitochondria show a low level of primary sequence conservation and exhibit ‘bizarre’ secondary structures, lacking complete domains of the common cloverleaf. Such sequences are hard to detect and hence frequently missed in computational analyses and mitochondrial genome annotation. Here, we introduce an automatic annotation procedure for mitochondrial tRNA genes in Metazoa based on sequence and structural information in manually curated covariance models. The method, applied to re-annotate 1876 available metazoan mitochondrial RefSeq genomes, allows to distinguish between remaining functional genes and degrading ‘pseudogenes’, even at early stages of divergence. The subsequent analysis of a comprehensive set of mitochondrial tRNA genes gives new insights into the evolution of structures of mitochondrial tRNA sequences as well as into the mechanisms of genome rearrangements. We find frequent losses of tRNA genes concentrated in basal Metazoa, frequent independent losses of individual parts of tRNA genes, particularly in Arthropoda, and wide-spread conserved overlaps of tRNAs in opposite reading direction. Direct evidence for several recent Tandem Duplication-Random Loss events is gained, demonstrating that this mechanism has an impact on the appearance of new mitochondrial gene orders

Subchronic toxicity of Baltic herring oil and its fractions in the rat II: Clinical observations and toxicological parameters

This study aimed to increase the knowledge about the toxicity of fish-derived organohalogen pollutants in mammals. The strategy chosen was to separate organohalogen pollutants derived from Baltic herring (Clupea harengus) fillet, in order to obtain fractions with differing proportions of identified and unidentified halogenated pollutants, and to perform a subchronic toxicity study in rats, essentially according to the OECD guidelines, at three dose levels. Nordic Sea Iodda (Mallotus villosus) oil, with low levels of persistent organohalogen pollutants, was used as an additional control diet. The toxicological examination showed that exposure to Baltic herring oil and its fractions at dose levels corresponding to a human intake in the range of 1.6 to 34.4 kg Baltic herring per week resulted in minimal effects. The spectrum of effects was similar to that, which is observed after low-level exposure to pollutants such as chlorinated dibenzo-p-dioxins and dibenzofurans (CDD/F) and chlorinated biphenyls, despite the fact that these contaminants contribute to a minor part of the extractable organically bound chlorine (EOC1). The study confirmed previous findings that induction of hepatic ethoxyresorufin deethylase (EROD) activity takes place at daily intake levels 0.15 ng fish-derived CDD/F-TEQs/kg body weight. The study also demonstrated that hepatic vitamin A reduction takes place at somewhat higher daily exposure levels, i.e. 0.16-0.30 ng fish-derived CDD/F-TEQs/kg body weight. Halogenated fatty acids, the major component of EOC1, could not be linked to any of the measured effects. From a risk management point of view, the study provides important new information of effect levels for Ah-receptor mediated responses following low level exposure to organohalogen compounds from a matrix relevant for human exposure

CERT1 mutations perturb human development by disrupting sphingolipid homeostasis

Neural differentiation, synaptic transmission, and action potential propagation depend on membrane sphingolipids, whose metabolism is tightly regulated. Mutations in the ceramide transporter CERT (CERT1), which is involved in sphingolipid biosynthesis, are associated with intellectual disability, but the pathogenic mechanism remains obscure. Here, we characterize 31 individuals with de novo missense variants in CERT1. Several variants fall into a previously uncharacterized dimeric helical domain that enables CERT homeostatic inactivation, without which sphingolipid production goes unchecked. The clinical severity reflects the degree to which CERT autoregulation is disrupted, and inhibiting CERT pharmacologically corrects morphological and motor abnormalities in a Drosophila model of the disease, which we call ceramide transporter (CerTra) syndrome. These findings uncover a central role for CERT autoregulation in the control of sphingolipid biosynthetic flux, provide unexpected insight into the structural organization of CERT, and suggest a possible therapeutic approach for patients with CerTra syndrome