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Crossing the ice: An Iron Age to medieval mountain pass at Lendbreen, Norway
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Segregation analysis comparing liability and quantitative trait models for hypertension using the Genetic Analysis Workshop 13 simulated data
Discrete (qualitative) data segregation analysis may be performed assuming the liability model, which involves an underlying normally distributed quantitative phenotype. The appropriateness of the liability model for complex traits is unclear. The Genetic Analysis Workshop 13 simulated data provides measures on systolic blood pressure, a highly complex trait, which may be dichotomized into a discrete trait (hypertension). We perform segregation analysis under the liability model of hypertensive status as a qualitative trait and compare this with results using systolic blood pressure as a quantitative trait (without prior knowledge at that stage of the true underlying simulation model) using 1050 pedigrees ascertained from four replicates on the basis of at least one affected member. Both analyses identify models with major genes and polygenic components to explain the family aggregation of systolic blood pressure. Neither of the methods estimates the true parameters well (as the true model is considerably more complicated than those considered for the analysis), but both identified the most complicated model evaluated as the preferred model. Segregation analysis of complex diseases using relatively simple models is unlikely to provide accurate parameter estimates but is able to indicate major gene and/or polygenic components in familial aggregation of complex diseases
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Ecological globalisation, serial depletion and the medieval trade of walrus rostra
The impacts of early ecological globalisation may have had profound economic and environmental consequences for human settlements and animal populations. Here, we review the extent of such historical impacts by investigating the medieval trade of walrus (Odobenus rosmarus rosmarus) ivory. We use an interdisciplinary approach including chaĂźne opĂ©ratoire, ancient DNA (aDNA), stable isotope and zooarchaeological analysis of walrus rostra (skull sections) to identify their biological source and subsequent trade through Indigenous and urban networks. This approach complements and improves the spatial resolution of earlier aDNA observations, and we conclude that almost all medieval European finds of walrus rostra likely derived from Greenland. We further find that shifting urban nodes redistributed the traded ivory and that the latest medieval rostra finds were from smaller, often female, walruses of a distinctive DNA clade, which is especially prevalent in northern Greenland. Our results suggest that more and smaller animals were targeted at increasingly untenable distances, which reflects a classic pattern of resource depletion. We consider how the trade of walrus and elephant ivory intersected, and evaluate the extent to which emergent globalisation and the âresource curseâ contributed to the abandonment of Norse Greenland
Free randomness can be amplified
Are there fundamentally random processes in nature? Theoretical predictions,
confirmed experimentally, such as the violation of Bell inequalities, point to
an affirmative answer. However, these results are based on the assumption that
measurement settings can be chosen freely at random, so assume the existence of
perfectly free random processes from the outset. Here we consider a scenario in
which this assumption is weakened and show that partially free random bits can
be amplified to make arbitrarily free ones. More precisely, given a source of
random bits whose correlation with other variables is below a certain
threshold, we propose a procedure for generating fresh random bits that are
virtually uncorrelated with all other variables. We also conjecture that such
procedures exist for any non-trivial threshold. Our result is based solely on
the no-signalling principle, which is necessary for the existence of free
randomness.Comment: 5+7 pages, 2 figures. Updated to match published versio
Sexing Viking Age horses from burial and non-burial sites in Iceland using ancient DNA
© 2018 The Authors Horses are the most common grave goods found in Icelandic Viking Age graves. Horse skeletons have previously been sexed based on pelvis shape and the presence of canine teeth in male horses over 4â5 years of age. Morphological data has shown that all horses from Icelandic burials that were amenable to sexing were male. Yet the use of morphological methods to determine sex is problematic since they rely on finding a well-preserved pelvis and/or robust canine teeth. Furthermore, quantitative data underlying the features of the horse pelvis used for sexing is lacking and canine teeth have been reported to occur in mares. In this study we build upon and extend recently developed methodologies to make use of shotgun sequencing of ancient DNA (aDNA) for molecular sexing of Viking Age horse remains. With minimal sequencing effort we identified the sex of the largest collection (n = 22) of Viking Age Icelandic horses studied to date, sourced from both burial (n = 19) and non-burial (n = 3) sites. Our results revealed a male to female sex bias ratio of 18:1 in burial sites, versus 0:3 in non-burial sites. These findings support the significant over-representation of male horses in Viking Age graves in Iceland, yet show that âalbeit rareâ mares could also be selected for ritual burial in Viking Age Iceland. This cost-effective method provides statistical confidence to allow for sexing of highly fragmented archaeological specimens with low endogenous DNA content
Fish for the city: meta-analysis of archaeological cod remains and the growth of London's northern trade
The growth of medieval cities in Northern Europe placed new demands on food supply, and led to the import of fish from increasingly distant fishing grounds. Quantitative analysis of cod remains from London provides revealing insight into the changing patterns of supply that can be related to known historical events and circumstances. In particular it identifies a marked increase in imported cod from the thirteenth century AD. That trend continued into the fifteenth and sixteenth centuries, after a short downturn, perhaps attributable to the impact of the Black Death, in the mid fourteenth century. The detailed pattern of fluctuating abundance illustrates the potential of archaeological information that is now available from the high-quality urban excavations conducted in London and similar centres during recent decades
Early responses to H7N9 in southern mainland China
This article is made available through the Brunel Open Access Publishing Fund. © 2014 Goodwin and Sun; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the
Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public
Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this
article, unless otherwise stated.Background: H7N9 posed potentially serious health challenges for Chinese society. The previous SARS outbreak in this country was accompanied by contradictory information, while worries about wide-spread influenza led to discrimination worldwide. Early understanding of public threat perceptions is therefore important for effective public health communication and intervention. Methods: We interviewed 1011 respondents by phone two weeks after the first case. Questions examined risk awareness and media use, beliefs about the emergence of the threat and those most at risk, anxiety about infection and preventive and avoidant behaviours. Results: Results demonstrate moderate levels of anxiety but relatively high levels of trust towards government officials. Threat emergence was associated with hygiene levels, temperature change, floating pigs in the Huangpu River and migration to the city. Anxiety predicted both recommended and non-recommended behavioural changes. Conclusions: Comparatively high levels of trust in Chinese government advice about H7N9 contrast positively with previous pandemic communications in China. Anxiety helped drive both recommended and non-recommended behaviours, with potentially important economic and social implications. This included evidence of 'otheringâ of those associated with the threat (e.g. migrants). Findings emphasise the need to manage public communications early during new influenza outbreaks.Fudan Tydall Centre and Fudan Media and Public Opinion Center
Melarsoprol cyclodextrin inclusion complexes as promising oral candidates for the treatment of human African trypanosomiasis
Human African trypanosomiasis (HAT), or sleeping sickness, results from infection with the protozoan parasites <i>Trypanosoma brucei</i> (<i>T.b.</i>) <i>gambiense</i> or <i>T.b.rhodesiense</i> and is invariably fatal if untreated. There are 60 million people at risk from the disease throughout sub-Saharan Africa. The infection progresses from the haemolymphatic stage where parasites invade the blood, lymphatics and peripheral organs, to the late encephalitic stage where they enter the central nervous system (CNS) to cause serious neurological disease. The trivalent arsenical drug melarsoprol (Arsobal) is the only currently available treatment for CNS-stage <i>T.b.rhodesiense</i> infection. However, it must be administered intravenously due to the presence of propylene glycol solvent and is associated with numerous adverse reactions. A severe post-treatment reactive encephalopathy occurs in about 10% of treated patients, half of whom die. Thus melarsoprol kills 5% of all patients receiving it. Cyclodextrins have been used to improve the solubility and reduce the toxicity of a wide variety of drugs. We therefore investigated two melarsoprol cyclodextrin inclusion complexes; melarsoprol hydroxypropyl-͎-cyclodextrin and melarsoprol randomly-methylated-β-cyclodextrin. We found that these compounds retain trypanocidal properties <i>in vitro</i> and cure CNS-stage murine infections when delivered orally, once per day for 7-days, at a dosage of 0.05 mmol/kg. No overt signs of toxicity were detected. Parasite load within the brain was rapidly reduced following treatment onset and magnetic resonance imaging showed restoration of normal blood-brain barrier integrity on completion of chemotherapy. These findings strongly suggest that complexed melarsoprol could be employed as an oral treatment for CNS-stage HAT, delivering considerable improvements over current parenteral chemotherapy
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