353 research outputs found

    Blood Protein Residues on Lithic Artifacts from Two Archaeological Sites in the De Long Mountains, Northwestern Alaska

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    Immunological analysis of blood residues was performed on 25 lithic artifacts from two archaeological sites (DEL-166 and DEL-168) in the De Long Mountains of northwestern Alaska. Blood residues occur on five artifact types: retouched flakes; end scrapers; flake burins; bifaces; and wedge-shaped microblade cores. Fourteen (56%) of the 25 analyzed artifacts react positively to six animal antisera and to human blood. Besides human blood, identified residues include the blood of sturgeon (Acipenseridae), deer (Cervidae), rabbit (Leporidae), bear (Ursus), "cat" (Felidae) and "mouse" (Rodentia). Although the application of blood residue analysis to archaeological problems is a relatively new application of an old forensic method, it may provide useful information about artifact function and animal procurement from sites where faunal remains are not preserved.On a procĂ©dĂ© Ă  une analyse immunologique de rĂ©sidus sanguins sur 25 artefacts lithiques provenant de deux sites archĂ©ologiques (DEL-166 et DEL-168) dans les monts De Long du nord-ouest de l'Alaska. On a trouvĂ© des rĂ©sidus sanguins sur cinq types d'artefacts: Ă©clats retouchĂ©s; grattoirs sur lame; burins faits d'Ă©clats; bifaces; et nuclĂ©us microlames cunĂ©iformes. Quatorze (56 p. cent) des 25 artefacts analysĂ©s ont rĂ©agi positivement Ă  six antisĂ©rums de provenance animale et Ă  du sang humain. Outre le sang de provenance humaine, les rĂ©sidus identifiĂ©s comprennent le sang d'esturgeon (Acipenseridae), de chevreuil (Cervidae), de lapin (Leporidae), d'ours (Ursus), de «chat» (Felidae) et de «souris» (Rodentia). Bien que l'application de l'analyse de rĂ©sidus sanguins Ă  des questions d'ordre archĂ©ologique soit une application relativement nouvelle d'une ancienne mĂ©thode mĂ©dico-lĂ©gale, elle peut fournir des renseignements utiles sur la fonction de l'artefact et sur l'approvisionnement en animaux dans les cas de sites oĂč les vestiges de la faune n'ont pas Ă©tĂ© conservĂ©s

    On the spread of epidemics in a closed heterogeneous population

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    Heterogeneity is an important property of any population experiencing a disease. Here we apply general methods of the theory of heterogeneous populations to the simplest mathematical models in epidemiology. In particular, an SIR (susceptible-infective-removed) model is formulated and analyzed for different sources of heterogeneity. It is shown that a heterogeneous model can be reduced to a homogeneous model with a nonlinear transmission function, which is given in explicit form. The widely used power transmission function is deduced from a heterogeneous model with the initial gamma-distribution of the disease parameters. Therefore, a mechanistic derivation of the phenomenological model, which mimics reality very well, is provided. The equation for the final size of an epidemic for an arbitrary initial distribution is found. The implications of population heterogeneity are discussed, in particular, it is pointed out that usual moment-closure methods can lead to erroneous conclusions if applied for the study of the long-term behavior of the model.Comment: 23 pages, 2 figure

    Foundation and empire : a critique of Hardt and Negri

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    In this article, Thompson complements recent critiques of Hardt and Negri's Empire (see Finn Bowring in Capital and Class, no. 83) using the tools of labour process theory to critique the political economy of Empire, and to note its unfortunate similarities to conventional theories of the knowledge economy

    Film support and the challenge of ‘sustainability’: on wing design, wax and feathers, and bolts from the blue

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    In recognition of the importance of film in generating both economic and cultural value, the UK Labour government set up a new agency – the United Kingdom Film Council (UKFC) – in 2000 with a remit to build a sustainable film industry. But, reflecting a plethora of differing expectations in relation to the purposes behind public support for film, the UKFC's agenda shifted and broadened over the organisation's lifetime (2000–11). Apparently unconvinced by the UKFC's achievements, the Coalition government which came to power in May 2010 announced the Council's abolition and reassigned its responsibilities as part of a general cost-cutting strategy. Based on original empirical research, this article examines how the UKFC's sense of strategic direction was determined, how and why the balance of objectives it pursued changed over time and what these shifts tell us about the nature of film policy and the challenges facing bodies that are charged with enacting it in the twenty-first century

    Till death (or an intruder) do us part: intrasexual-competition in a monogamous Primate

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    Polygynous animals are often highly dimorphic, and show large sex-differences in the degree of intra-sexual competition and aggression, which is associated with biased operational sex ratios (OSR). For socially monogamous, sexually monomorphic species, this relationship is less clear. Among mammals, pair-living has sometimes been assumed to imply equal OSR and low frequency, low intensity intra-sexual competition; even when high rates of intra-sexual competition and selection, in both sexes, have been theoretically predicted and described for various taxa. Owl monkeys are one of a few socially monogamous primates. Using long-term demographic and morphological data from 18 groups, we show that male and female owl monkeys experience intense intra-sexual competition and aggression from solitary floaters. Pair-mates are regularly replaced by intruding floaters (27 female and 23 male replacements in 149 group-years), with negative effects on the reproductive success of both partners. Individuals with only one partner during their life produced 25% more offspring per decade of tenure than those with two or more partners. The termination of the pair-bond is initiated by the floater, and sometimes has fatal consequences for the expelled adult. The existence of floaters and the sporadic, but intense aggression between them and residents suggest that it can be misleading to assume an equal OSR in socially monogamous species based solely on group composition. Instead, we suggest that sexual selection models must assume not equal, but flexible, context-specific, OSR in monogamous species.Wenner-Gren Foundation, L.S.B. Leakey Foundation, the National Geographic Society, National Science Foundation (BCS- 0621020), the University of Pennsylvania Research Foundation and the Zoological Society of San Diego, German Science Foundation (HU 1746-2/1

    Global warming and mass extinctions associated with large igneous province volcanism

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    The coincidence of large igneous province (LIP) eruptions with at least three, if not all of the “Big Five” biotic crises of the Phanerozoic implies that volcanism is a key driver of mass extinctions. Many LIP-induced extinction scenarios invoke global warming, caused primarily (but not exclusively) by greenhouse gases emitted at the site of LIP emplacement and by contact metamorphism of carbon-rich host rocks. Here we explore a) the climate-changing products of volcanism including sulfur dioxide (SO2), carbon dioxide (CO2) and methane (CH4) from eruptions, contact metamorphism, and melting (dissociation) of gas hydrates; b) their deadly effects, including marine anoxia and thermal stress; c) increasingly sophisticated paleotemperature proxies (e.g. ή18O of shell material) through case studies of the best-known LIP-warming-extinction nexi; and d) global warming through the lens of the putative “Anthropocene” extinction

    Public Perceptions of Human Excretion-Based Fertiliser in England and Japan

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    ......This research was funded by the UKRI/ ESRC (grant number ES/W011913/1) and the JSPS (grant number JPJSJRP 20211704)

    The cost of promiscuity: sexual transmission of Nosema microsporidian parasites in polyandrous honey bees

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    Multiple mating (and insemination) by females with different males, polyandry, is widespread across animals, due to material and/or genetic benefits for females. It reaches particularly high levels in some social insects, in which queens can produce significantly fitter colonies by being polyandrous. It is therefore a paradox that two thirds of eusocial hymenopteran insects appear to be exclusively monandrous, in spite of the fitness benefits that polyandry could provide. One possible cost of polyandry could be sexually transmitted parasites, but evidence for these in social insects is extremely limited. Here we show that two different species of Nosema microsporidian parasites can transmit sexually in the honey bee Apis mellifera. Honey bee males that are infected by the parasite have Nosema spores in their semen, and queens artificially inseminated with either Nosema spores or the semen of Nosema-infected males became infected by the parasite. The emergent and more virulent N. ceranae achieved much higher rates of infection following insemination than did N. apis. The results provide the first quantitative evidence of a sexually transmitted disease (STD) in social insects, indicating that STDs may represent a potential cost of polyandry in social insects
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