Isotopic analysis of faunal material from South Uist, Western Isles, Scotland

This paper reports on the results from stable isotope analysis of faunal bone collagen from a number of Iron Age and later sites on the island of South Uist, in the Western Isles, Scotland. This preliminary investigation into the isotopic signatures of the fauna is part of a larger project to model the interaction between humans, animals, and the broader environment in the Western Isles. The results demonstrate that the island fauna data fall within the range of expected results for the UK, with the terrestrial herbivorous diets of cattle and sheep confi rmed. The isotopic composition for pigs suggests that some of these animals had an omnivorous diet, whilst a single red deer value might be suggestive of the consumption of marine foods, such as by grazing on seaweed. However, further analysis is needed in order to verify this anomalous isotopic ratio

Latitudinal gradient in dairy production with the introduction of farming in Atlantic Europe

International audienceThe introduction of farming had far-reaching impacts on health, social structure and demography. Although the spread of domesticated plants and animals has been extensively tracked, it is unclear how these nascent economies developed within different environmental and cultural settings. Using molecular and isotopic analysis of lipids from pottery, here we investigate the foods prepared by the earliest farming communities of the European Atlantic seaboard. Surprisingly, we find an absence of aquatic foods, including in ceramics from coastal sites, except in the Western Baltic where this tradition continued from indigenous ceramic using hunter-gatherer-fishers. The frequency of dairy products in pottery increased as farming was progressively introduced along a northerly latitudinal gradient. This finding implies that early farming communities needed time to adapt their economic practices before expanding into more northerly areas. Latitudinal differences in the scale of dairy production might also have influenced the evolution of adult lactase persistence across Europe

Foraging Fidelity as a Recipe for a Long Life: Foraging Strategy and Longevity in Male Southern Elephant Seals

Identifying individual factors affecting life-span has long been of interest for biologists and demographers: how do some individuals manage to dodge the forces of mortality when the vast majority does not? Answering this question is not straightforward, partly because of the arduous task of accurately estimating longevity in wild animals, and of the statistical difficulties in correlating time-varying ecological covariables with a single number (time-to-event). Here we investigated the relationship between foraging strategy and life-span in an elusive and large marine predator: the Southern Elephant Seal (Mirounga leonina). Using teeth recovered from dead males on îles Kerguelen, Southern Ocean, we first aged specimens. Then we used stable isotopic measurements of carbon () in dentin to study the effect of foraging location on individual life-span. Using a joint change-point/survival modelling approach which enabled us to describe the ontogenetic trajectory of foraging, we unveiled how a stable foraging strategy developed early in life positively covaried with longevity in male Southern Elephant Seals. Coupled with an appropriate statistical analysis, stable isotopes have the potential to tackle ecological questions of long standing interest but whose answer has been hampered by logistic constraints

The Origins of Lactase Persistence in Europe

Lactase persistence (LP) is common among people of European ancestry, but with the exception of some African, Middle Eastern and southern Asian groups, is rare or absent elsewhere in the world. Lactase gene haplotype conservation around a polymorphism strongly associated with LP in Europeans (−13,910 C/T) indicates that the derived allele is recent in origin and has been subject to strong positive selection. Furthermore, ancient DNA work has shown that the −13,910*T (derived) allele was very rare or absent in early Neolithic central Europeans. It is unlikely that LP would provide a selective advantage without a supply of fresh milk, and this has lead to a gene-culture coevolutionary model where lactase persistence is only favoured in cultures practicing dairying, and dairying is more favoured in lactase persistent populations. We have developed a flexible demic computer simulation model to explore the spread of lactase persistence, dairying, other subsistence practices and unlinked genetic markers in Europe and western Asia's geographic space. Using data on −13,910*T allele frequency and farming arrival dates across Europe, and approximate Bayesian computation to estimate parameters of interest, we infer that the −13,910*T allele first underwent selection among dairying farmers around 7,500 years ago in a region between the central Balkans and central Europe, possibly in association with the dissemination of the Neolithic Linearbandkeramik culture over Central Europe. Furthermore, our results suggest that natural selection favouring a lactase persistence allele was not higher in northern latitudes through an increased requirement for dietary vitamin D. Our results provide a coherent and spatially explicit picture of the coevolution of lactase persistence and dairying in Europe

Provenancing Archaeological Wool Textiles from Medieval Northern Europe by Light Stable Isotope Analysis (δ13C, δ15N, δ2H)

We investigate the origin of archaeological wool textiles preserved by anoxic waterlogging from seven medieval archaeological deposits in north-western Europe (c. 700-1600 AD), using geospatial patterning in carbon (δ13C), nitrogen (δ15N) and non-exchangeable hydrogen (δ2H) composition of modern and ancient sheep proteins. δ13C, δ15N and δ2H values from archaeological wool keratin (n = 83) and bone collagen (n = 59) from four sites were interpreted with reference to the composition of modern sheep wool from the same regions. The isotopic composition of wool and bone collagen samples clustered strongly by settlement; inter-regional relationships were largely parallel in modern and ancient samples, though landscape change was also significant. Degradation in archaeological wool samples, examined by elemental and amino acid composition, was greater in samples from Iceland (Reykholt) than in samples from north-east England (York, Newcastle) or northern Germany (Hessens). A nominal assignment approach was used to classify textiles into local/non-local at each site, based on maximal estimates of isotopic variability in modern sheep wool. Light element stable isotope analysis provided new insights into the origins of wool textiles, and demonstrates that isotopic provenancing of keratin preserved in anoxic waterlogged contexts is feasible. We also demonstrate the utility of δ2H analysis to understand the location of origin of archaeological protein samples

Ancient proteins provide evidence of dairy consumption in eastern Africa

Consuming the milk of other species is a unique adaptation of Homo sapiens, with implications for health, birth spacing and evolution. Key questions nonetheless remain regarding the origins of dairying and its relationship to the genetically-determined ability to drink milk into adulthood through lactase persistence (LP). As a major centre of LP diversity, Africa is of significant interest to the evolution of dairying. Here we report proteomic evidence for milk consumption in ancient Africa. Using liquid chromatography tandem mass spectrometry (LC-MS/MS) we identify dairy proteins in human dental calculus from northeastern Africa, directly demonstrating milk consumption at least six millennia ago. Our findings indicate that pastoralist groups were drinking milk as soon as herding spread into eastern Africa, at a time when the genetic adaptation for milk digestion was absent or rare. Our study links LP status in specific ancient individuals with direct evidence for their consumption of dairy products

Diabetic ketoacidosis

Diabetic ketoacidosis (DKA) is the most common acute hyperglycaemic emergency in people with diabetes mellitus. A diagnosis of DKA is confirmed when all of the three criteria are present — ‘D’, either elevated blood glucose levels or a family history of diabetes mellitus; ‘K’, the presence of high urinary or blood ketoacids; and ‘A’, a high anion gap metabolic acidosis. Early diagnosis and management are paramount to improve patient outcomes. The mainstays of treatment include restoration of circulating volume, insulin therapy, electrolyte replacement and treatment of any underlying precipitating event. Without optimal treatment, DKA remains a condition with appreciable, although largely preventable, morbidity and mortality. In this Primer, we discuss the epidemiology, pathogenesis, risk factors and diagnosis of DKA and provide practical recommendations for the management of DKA in adults and children

Spectre continu d'émission d'un plasma de mercure à la limite des séries 6'3P2 aux pressions comprises entre 3 torr et 70 torr

1° Les mesures des luminances spectrales énergétiques, by, du spectre continu du mercure, à diverses pressions comprises entre 3 torr et 70 torr, confèrent aux représentations graphiques [FORMULE] un caractère linéaire. 2° Les pentes de ces représentations demeurent constantes ou varient peu quand varie la pression de vapeur. 3° A une même fréquence, bv varie selon la pression, conformément à la relation : [FORMULE] 4° Prenant pour base la théorie des spectres continus «free-free » et «free-bound » de Kramers-Unsöld, les représentations [FORMULE] proposent une température électronique Te de l'ordre de 5950° K. 5° Le nombre d'ions Hg+ ou d'électrons est de l'ordre de 7.1014 cm-3.Balasse Georges, Lemmens M.-L. Spectre continu d'émission d'un plasma de mercure à la limite des séries 6'3P2 aux pressions comprises entre 3 torr et 70 torr. In: Bulletin de la Classe des sciences, tome 58, 1972. pp. 775-787

Neurochemical characterization of pathways expressing plasma membrane monoamine transporter in the rat brain

International audienceNeurotransmitter transporters play an important role in the control of synaptic transmission by ensuring the clearance of transmitters liberated in the synaptic cleft. In the case of monoaminergic neurotransmitters, this clearance is carried out by high-affinity reuptake transporters located in the plasma membrane of the presynaptic terminals. Recently plasma membrane monoamine transporter (PMAT), a transporter from the SLC29 (equilibrative nucleoside transporter) family, was shown to transport in vitro monoaminergic neurotransmitters, in particular dopamine and serotonin, nearly as efficiently as the high-affinity transporters. This transporter, well expressed in CNS, represents an interesting candidate for the control and modulation of aminergic pathways. We performed an extensive study of the distribution of PMAT in the rat brain. Our results highlight PMAT expression in brain regions which play a pivotal role in significant CNS functions and human neuropathologies. Using in situ hybridization immunohistochemistry co-labeling, PMAT mRNA was found in various neuron subtypes, including glutamatergic neurons of the hippocampus, mitral cells of the olfactory bulbs and GABAergic neurons in the substantia nigra pars reticulata and hypothalamus. Paradoxically, rat PMAT mRNA was found in some but not all monoaminergic nuclei. It was on the contrary predominantly expressed in major cholinergic groups throughout the brain, including brainstem motor nuclei, components of the basal forebrain cholinergic system and cholinergic interneurons of the striatum. These systems, implicated in locomotion, associative and spatial memory and reward-related learning, are disrupted at early stages of Parkinson's and Alzheimer's disease. Taken together, our observations support a role for PMAT in monoamine uptake in cholinergic neurons

Comparaison des valeurs calculées du coefficient e (v) d'émission spectrale d'un plasma de mercure aux valeurs mesurées, dans la région du continuum limite 6p1P1 des séries spectrales

Résumé. — Des mesures de luminances spectrales énergétiques b(y) d'un plasma conduisent à la détermination de la température électronique Te et de coefficients d'émission spectrale e(v)expérimental. L'observation des raies de fin de séries spectrales procure par la relation d'Inglis et Teller l'ordre de grandeur de la densité électronique ne. Sur la base des valeurs de Te et ne, la théorie de Kramers-Unsöld-Griem donne lieu à la valeur calculée, e(v)calculé, du coefficient d'émission spectrale du plasma sous la pression de vapeur saturante 30 torr. La comparaison des valeurs calculée et expérimentale est considérée dans deux cas : on admet pour facteurs de Gaunt la valeur 1 ; on confère à ces facteurs des valeurs extraites des tables de Karzas et Latter.Balasse Georges, Lemmens M.-L. Comparaison des valeurs calculées du coefficient e (v) d'émission spectrale d'un plasma de mercure aux valeurs mesurées, dans la région du continuum limite 6p1P1 des séries spectrales. In: Bulletin de la Classe des sciences, tome 61, 1975. pp. 504-523