scholarly journals Perfluoroalkyl substances in circum-ArcticRangifer: caribou and reindeer

2021 ◽  
Author(s):  
Anna Maria Roos ◽  
Mary Gamberg ◽  
Derek Muir ◽  
Anna Kärrman ◽  
Pernilla Carlsson ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Rangifer Tarandus ◽  
Perfluoroalkyl Substances ◽  
Sulfonic Acids ◽  
Military Base ◽  
Wet Weight ◽  
The One ◽  
Southwest Greenland

AbstractLivers of caribou and reindeer (Rangifer tarandus) from Canada (n = 146), Greenland (n = 30), Svalbard (n = 7), and Sweden (n = 60) were analyzed for concentrations of eight perfluoroalkyl carboxylic acids and four perfluoroalkane sulfonic acids. In Canadian caribou, PFNA (range < 0.01–7.4 ng/g wet weight, ww) and PFUnDA (<0.01–5.6 ng/g ww) dominated, whereas PFOS predominated in samples from South Greenland, Svalbard, and Sweden, although the highest concentrations were found in caribou from Southwest Greenland (up to 28 ng/g ww). We found the highest median concentrations of all PFAS except PFHxS in Akia-Maniitsoq caribou (Southwest Greenland, PFOS 7.2–19 ng/g ww, median 15 ng/g ww). The highest concentrations of ΣPFAS were also found in Akia-Maniitoq caribou (101 ng/g ww) followed by the nearby Kangerlussuaq caribou (45 ng/g ww), where the largest airport in Greenland is situated, along with a former military base. Decreasing trends in concentrations were seen for PFOS in the one Canadian and three Swedish populations. Furthermore, PFNA, PFDA, PFUnDA, PFDoDA, and PFTrDA showed decreasing trends in Canada’s Porcupine caribou between 2005 and 2016. In Sweden, PFHxS increased in the reindeer from Norrbotten between 2003 and 2011. The reindeer from Västerbotten had higher concentrations of PFNA and lower concentrations of PFHxS in 2010 compared to 2002. Finally, we observed higher concentrations in 2010 compared to 2002 (albeit statistically insignificant) for PFHxS in Jämtland, while PFNA, PFDA, PFUnDA, PFDoDA, and PFTrDA showed no difference at all.

Fatty acid oxidation by mitochondria from cold-fasted rats

1960 ◽  
Vol 198 (3) ◽  
pp. 632-636 ◽  
Author(s):  
E. J. Masoro ◽  
Edith Porter
Keyword(s):  
Metabolic Pathways ◽  
Dry Weight ◽  
Liver Mitochondria ◽  
Acid Oxidation ◽  
Surprising Result ◽  
Liver Slices ◽  
Wet Weight ◽  
Liver Homogenates ◽  
The One ◽  
Fasted Rats

Mitochondria from ‘cold-fasted’ rats oxidized about as much acetate-1-C14 to C14O2 as did mitochondria from control rats when the data were expressed on the basis of dry weight of the mitochondria. This was a most surprising result because liver slices (wet weight basis) and liver homogenates (protein content basis) from cold-fasted rats form far less C14O2 from acetate-1-C14 than do similar preparations from control rats. The possible reasons for these differences in results with liver slices and liver homogenates on the one hand and liver mitochondria on the other are discussed. Mitochondria from cold-fasted rats were also found to oxidize palmitate-1-C14 to C14O2 as rapidly as the mitochondria from control rats, thereby confirming the results obtained with liver slices. Carbohydrate metabolism failed to promote palmitate oxidation by mitochondria from cold-fasted rats; just the opposite result is obtained with liver slices. The use of mitochondria to study the regulation of multistep metabolic pathways is discussed.

Direct Conversion of Carboxylic Acids to Various Nitrogen-Containing Compounds in the One-Pot Exploiting Curtius Rearrangement

2019 ◽  
Vol 84 (17) ◽  
pp. 11323-11334 ◽  
Author(s):  
Arun Kumar ◽  
Naveen Kumar ◽  
Ritika Sharma ◽  
Gaurav Bhargava ◽  
Dinesh Mahajan
Keyword(s):  
Carboxylic Acids ◽  
Direct Conversion ◽  
One Pot ◽  
Curtius Rearrangement ◽  
The One ◽  
Nitrogen Containing Compounds

The effect of mineral supplements on nutrient concentrations and pool sizes in the alimentary tract of reindeer fed lichens or concentrates during the winter

1984 ◽  
Vol 62 (7) ◽  
pp. 1232-1241 ◽  
Author(s):  
H. Staaland ◽  
E. Jacobsen ◽  
R. G. White
Keyword(s):  
Rangifer Tarandus ◽  
Alimentary Tract ◽  
Nutrient Concentrations ◽  
Steady Increase ◽  
Mineral Supplement ◽  
Mineral Supplements ◽  
Mineral Supplementation ◽  
Wet Weight ◽  
Small Intestinal ◽  
Pool Sizes

Domestic reindeer (Rangifer tarandus tarandus L.), fed a mixed lichen or concentrate diet with or without a mineral supplement, were killed, and 21 segments of the digestive tract were analyzed for weight of digesta and concentrations of water, organic matter (OM), N, Ca, P, Mg, Na, K, Cl, and S. Trends in alimentary nutrient concentrations were of two patterns: (A) Ca, P, Mg, S, OM, and N increased in concentration per unit wet weight in ruminal to omasal contents and, followed by a decline from abomasal to jejunal contents, there was a steady increase to the rectal contents; (B) water, Na, Cl, and, with some modification, K decreased in concentration from the small intestinal to the rectal contents. The concentrate diet was associated with significantly increased body weight, plasma P levels, and N, P, and Mg levels in most sections of the alimentary tract. Mineral supplementation suppressed concentrations of N in the entire alimentary tract of lichen-fed reindeer but was associated with increased concentrations of P, Ca, and Mg in the entire tract of both the concentrate and lichen diets.

scholarly journals One step synthesis of Diflunisal using a Pd-diamine complex

2009 ◽  
Vol 7 (4) ◽  
pp. 818-826 ◽  
Author(s):  
Tuula Kylmälä ◽  
Jan Tois ◽  
Youjun Xu ◽  
Robert Franzén
Keyword(s):  
Carboxylic Acids ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Cross Coupling Reaction ◽  
One Step ◽  
The One

AbstractDiflunisal and Felbinac, two FDA-approved NSAIDs and other biphenyl carboxylic acids were prepared in one step by a simple and clean Suzuki cross-coupling reaction using an easily synthesized, air and moisture stable, palladium-diamine complex. The yield (93%) for the one-step preparation of Diflunisal is the best reported without using a glovebox and a phoshine-based catalyst.

scholarly journals The bacterial population adherent to plant particles in the rumen of reindeer fed lichen, timothy hay or silage

Rangifer ◽  
1998 ◽  
Vol 18 (2) ◽  
pp. 55 ◽  
Author(s):  
Monica Alterskjær Olsen ◽  
Svein Disch Mathiesen
Keyword(s):  
Carboxymethyl Cellulose ◽  
Rangifer Tarandus ◽  
Bacterial Population ◽  
Anaerobic Bacteria ◽  
Negative Influence ◽  
Cellulolytic Bacteria ◽  
Bacterial Strains ◽  
Butyrivibrio Fibrisolvens ◽  
Rangifer Tarandus Tarandus ◽  
Wet Weight

Male reindeer (Rangifer tarandus tarandus) calves taken from a natural winter pasture were given ad lib. access to lichen (n = 3), timothy silage (n = 3) and hay (n = 3) for 7 weeks. Median numbers of viable anaerobic bacteria adherent to the plant particles (cells/g wet weight of rumen solids), growing on a habitat simulating medium (M8V), were significantly higher (P = 0.05) in the rumen of reindeer fed lichen (26.5 x 109- 53.0 x 109) and hay (4.0 x 109- 40.5 x 109), compared to reindeer fed silage (1.15 x 109 - 3.25 x 109). Anaerobic bacterial strains (n = 551) from the plant particles obtained from the rumen of the nine reindeer examined, were isolated using an acid swollen cellulose medium (M8SC) and tested for their ability to hydrolyse carboxymethyl cellulose (CMC). The proportion of CMC hydrolysing adherent bacteria isolated from M8SC was significantly higher in reindeer fed hay (21.5%) compared ro animals fed lichen (5.3%) and silage (2.7%) (P = 0.05). The CMC hydrolysing bacterial srrains (n=42) isolated from reindeer fed hay where characterised as non-cellulolytic Butyrivibrio fibrisolvens (9.5%), cellulolytic B. fibrisolvens (50.0%), Clostridium sp. (2.4%) and unknowns (38.1%), while CMC hydrolysing strains (n=11) isolated from animals fed lichen and strains (n=4) isolated from animals fed silage where all characterised as B. fibrisolvens. None of the bacterial strains isolated from the rumen solids of reindeer fed lichen or silage were found to be cellulolytic. This study suggests that both lichen and timothy silage have a negative influence, compared to hay, on the numbers of cellulolytic bacteria adherent to the plant particles in the rumen of reindeer.

scholarly journals Energy-expending behaviour in frightened caribou when dispersed singly or in small bands

Rangifer ◽  
1997 ◽  
Vol 17 (1) ◽  
pp. 44
Author(s):  
Otto Blehr
Keyword(s):  
Canis Lupus ◽  
Rangifer Tarandus ◽  
Look Back ◽  
Save Energy ◽  
The One ◽  
Rangifer Tarandus Groenlandicus

The behaviour of single, and small bands of caribou (Rangifer tarandus groenlandicus) when confronted by humans was compared with the energy&mdash;saving behaviour zoologists have ascribed to caribou in encounters with non-hunting wolves (Canis lupus). When confronted by me, or upon getting my scent, caribou ran away on all occasions. Their flight was occasionally interrupted by short stops to look back in my direction, but would continue on all occasions until they were out of sight. This behaviour is inconsistent with the one ascribed to caribou by zoologists when the intruder is a wolf instead of a human. In their view, the caribou stop their flight soon after the wolf gives up the chase, and accordingly save energy owing to their ability to distinguish between hunting and non-hunting wolves. However, small bands of caribou, as well as single animals, have never been observed to behave in this manner. On the contrary, the behaviour of caribou in such encounters is known to follow the same pattern as in their encounters with humans. Energy&mdash;saving behaviour is, however, sometimes observed when caribou become inquisitive about something in their surroundings. They will then readily approach as well as try to get down-wind of the object. When the object does not induce fear, it may simply be ignored, or charged before the caribou calm down. The effect of this "confirming behaviour" is that energy which would otherwise have been spent in needless flights from non-predators is saved.

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