No future in archaeological heritage management?

Although the future is mentioned frequently in overarching aims and visions, and it is a major drive in the daily work of archaeological heritage managers and indeed heritage professionals more generally, it remains unclear precisely how an overall commitment to the future can best inform specific heritage practices. It seems that most archaeologists and other heritage professionals cannot easily express how they conceive of the future they work for, and how their work will impact on that future. The future tends to remain implicit in daily practice which operates in a continuing, rolling present. The authors argue that this needs to change because present-day heritage management may be much less beneficial for the future than we commonly expect

Simulations of Weighted Tree Automata

Simulations of weighted tree automata (wta) are considered. It is shown how such simulations can be decomposed into simpler functional and dual functional simulations also called forward and backward simulations. In addition, it is shown in several cases (fields, commutative rings, Noetherian semirings, semiring of natural numbers) that all equivalent wta M and N can be joined by a finite chain of simulations. More precisely, in all mentioned cases there exists a single wta that simulates both M and N. Those results immediately yield decidability of equivalence provided that the semiring is finitely (and effectively) presented.Comment: 17 pages, 2 figure

Guidelines for the establishment of microbiological criteria for foods

O Grupo de Trabalho Ocorrência Microbiológica na Cadeia Alimentar (GTOMCA) do Programa PortFIR considerou de grande importância o desenvolvimento de um documento que compilasse uma seleção de legislação e de informações relativas a Critérios Microbiológicos (CM), visando apoiar e facilitar, aos operadores e entidades do setor alimentar, a sua aplicação na validação do processo de produção, na segurança e/ou higiene dos géneros alimentícios, na adesão a boas práticas de fabrico dos mesmos, e/ou, ainda, na manutenção da sua qualidade durante o seu tempo de vida útil. Deste modo, o GTOMCA desenvolveu o Guia para o estabelecimento de critérios microbiológicos em géneros alimentícios, que foi publicado em abril de 2017, contemplando a identificação, caraterísticas e propósito dos CM, os fatores a considerar para a sua definição, nomeadamente: a categoria do alimento, o microrganismo e/ou as suas toxinas, os metabolitos e a virulência, os valores limite, o plano de amostragem, o tipo de utilização e consumo assim como o método de análise laboratorial, o ponto da cadeia alimentar onde se aplica, as medidas a tomar no caso de resultados não satisfatórios e a necessidade de revisão e atualização dos CM.The Working Group on Microbiological Occurrence on the Food Chain (GTOMCA) of Por tFIR Program considered unanimously, as an important need, the existence of a document with a selection and compilation of existing legislation and information concerning microbiological criteria (CM) as a tool to suppor t and facilitate its application by operators and entities in the food sector to validate the acceptability of the production process or the food safety or hygiene, the obser vance to good manufacturing practices or the maintenance of the food quality during its lifetime. So, GTOMCA developed a Guide for the establishment of microbiological criteria in foodstuf fs, which was published in April 2017, regarding the identification, characteristics and purpose of microbiological criteria, the factors to consider for its definition, identification, characteristics and purpose of CM and, as impor tant factors to consider the food categor y, the micro-organism and its metabolites, toxins and virulence factors, the limit values, the sampling plan, the type of food consumption as well as the analy tical method for testing the food, the point of the food chain where it is applied, the measures to be taken in the event of unsatisfactor y results and the need to review and update of the CM.info:eu-repo/semantics/publishedVersio

Foliar δ15N values characterize soil N cycling and reflect nitrate or ammonium preference of plants along a temperate grassland gradient

The natural abundance of stable 15N isotopes in soils and plants is potentially a simple tool to assess ecosystem N dynamics. Several open questions remain, however, in particular regarding the mechanisms driving the variability of foliar δ15N values of non-N2 fixing plants within and across ecosystems. The goal of the work presented here was therefore to: (1) characterize the relationship between soil net mineralization and variability of foliar Δδ15N (δ15Nleaf − δ15Nsoil) values from 20 different plant species within and across 18 grassland sites; (2) to determine in situ if a plant’s preference for NO3− or NH4+ uptake explains variability in foliar Δδ15N among different plant species within an ecosystem; and (3) test if variability in foliar Δδ15N among species or functional group is consistent across 18 grassland sites. Δδ15N values of the 20 different plant species were positively related to soil net mineralization rates across the 18 sites. We found that within a site, foliar Δδ15N values increased with the species’ NO3− to NH4+ uptake ratios. Interestingly, the slope of this relationship differed in direction from previously published studies. Finally, the variability in foliar Δδ15N values among species was not consistent across 18 grassland sites but was significantly influenced by N mineralization rates and the abundance of a particular species in a site. Our findings improve the mechanistic understanding of the commonly observed variability in foliar Δδ15N among different plant species. In particular we were able to show that within a site, foliar δ15N values nicely reflect a plant’s N source but that the direction of the relationship between NO3− to NH4+ uptake and foliar Δδ15N values is not universal. Using a large set of data, our study highlights that foliar Δδ15N values are valuable tools to assess plant N uptake patterns and to characterize the soil N cycle across different ecosystems

Heritage Futures - Comparative Approaches to Natural and Cultural Heritage Practices

This is the final version. Available on open access from UCL Press via the DOI in this recordWe present the book as a co-authored monograph because we acknowledge the collective contributions to the arguments developed within it, and the collaborative nature of the work. This has in itself been an experiment in finding a format in which diverse voices and views could productively speak to one another, while also acknowledging and foregrounding the diversity and range of different views, academic traditions and writing styles of contributors. As principal investigator, Harrison acted as the lead and coordinating author of the book, taking overall responsibilities for its editing and production. The co-investigators (DeSilvey, Holtorf, Macdonald) shared with Harrison editorial responsibilities for the individual thematic parts they each led, and for shaping the intellectual agenda of the book as a whole. However, we also felt it important to indicate the main authors of individual chapters within the book, to make clear specific contributions to the text and its arguments, and to highlight which named individuals were responsible for the empirical work that underpins them. Preservation of natural and cultural heritage is often said to be something that is done for the future, or on behalf of future generations, but the precise relationship of such practices to the future is rarely reflected upon. Heritage Futures draws on research undertaken over four years by an interdisciplinary, international team of 16 researchers and more than 25 partner organisations to explore the role of heritage and heritage-like practices in building future worlds. Engaging broad themes such as diversity, transformation, profusion and uncertainty, Heritage Futures aims to understand how a range of conservation and preservation practices across a number of countries assemble and resource different kinds of futures, and the possibilities that emerge from such collaborative research for alternative approaches to heritage in the Anthropocene. Case studies include the cryopreservation of endangered DNA in frozen zoos, nuclear waste management, seed biobanking, landscape rewilding, social history collecting, space messaging, endangered language documentation, built and natural heritage management, domestic keeping and discarding practices, and world heritage site management.Arts and Humanities Research Council (AHRC

Behavioral Modernity and the Cultural Transmission of Structured Information: The Semantic Axelrod Model

Cultural transmission models are coming to the fore in explaining increases in the Paleolithic toolkit richness and diversity. During the later Paleolithic, technologies increase not only in terms of diversity but also in their complexity and interdependence. As Mesoudi and O'Brien (2008) have shown, selection broadly favors social learning of information that is hierarchical and structured, and multiple studies have demonstrated that teaching within a social learning environment can increase fitness. We believe that teaching also provides the scaffolding for transmission of more complex cultural traits. Here, we introduce an extension of the Axelrod (1997} model of cultural differentiation in which traits have prerequisite relationships, and where social learning is dependent upon the ordering of those prerequisites. We examine the resulting structure of cultural repertoires as learning environments range from largely unstructured imitation, to structured teaching of necessary prerequisites, and we find that in combination with individual learning and innovation, high probabilities of teaching prerequisites leads to richer cultural repertoires. Our results point to ways in which we can build more comprehensive explanations of the archaeological record of the Paleolithic as well as other cases of technological change.Comment: 24 pages, 7 figures. Submitted to "Learning Strategies and Cultural Evolution during the Paleolithic", edited by Kenichi Aoki and Alex Mesoudi, and presented at the 79th Annual Meeting of the Society for American Archaeology, Austin TX. Revised 5/14/1

Biogenic Volatile Organic Compound and Respiratory CO2 Emissions after 13C-Labeling: Online Tracing of C Translocation Dynamics in Poplar Plants

Globally plants are the primary sink of atmospheric CO(2), but are also the major contributor of a large spectrum of atmospheric reactive hydrocarbons such as terpenes (e.g. isoprene) and other biogenic volatile organic compounds (BVOC). The prediction of plant carbon (C) uptake and atmospheric oxidation capacity are crucial to define the trajectory and consequences of global environmental changes. To achieve this, the biosynthesis of BVOC and the dynamics of C allocation and translocation in both plants and ecosystems are important.We combined tunable diode laser absorption spectrometry (TDLAS) and proton transfer reaction mass spectrometry (PTR-MS) for studying isoprene biosynthesis and following C fluxes within grey poplar (Populus x canescens) saplings. This was achieved by feeding either (13)CO(2) to leaves or (13)C-glucose to shoots via xylem uptake. The translocation of (13)CO(2) from the source to other plant parts could be traced by (13)C-labeled isoprene and respiratory (13)CO(2) emission.In intact plants, assimilated (13)CO(2) was rapidly translocated via the phloem to the roots within 1 hour, with an average phloem transport velocity of 20.3±2.5 cm h(-1). (13)C label was stored in the roots and partially reallocated to the plants' apical part one day after labeling, particularly in the absence of photosynthesis. The daily C loss as BVOC ranged between 1.6% in mature leaves and 7.0% in young leaves. Non-isoprene BVOC accounted under light conditions for half of the BVOC C loss in young leaves and one-third in mature leaves. The C loss as isoprene originated mainly (76-78%) from recently fixed CO(2), to a minor extent from xylem-transported sugars (7-11%) and from photosynthetic intermediates with slower turnover rates (8-11%).We quantified the plants' C loss as respiratory CO(2) and BVOC emissions, allowing in tandem with metabolic analysis to deepen our understanding of ecosystem C flux

Boreal forest soil carbon fluxes one year after a wildfire: Effects of burn severity and management

The extreme 2018 hot drought that affected central and northern Europe led to the worst wildfire season in Sweden in over a century. The Ljusdal fire complex, the largest area burnt that year (8995 ha), offered a rare opportunity to quantify the combined impacts of wildfire and post-fire management on Scandinavian boreal forests. We present chamber measurements of soil CO2 and CH4 fluxes, soil microclimate and nutrient content from five Pinus sylvestris sites for the first growing season after the fire. We analysed the effects of three factors on forest soils: burn severity, salvage-logging and stand age. None of these caused significant differences in soil CH4 uptake. Soil respiration, however, declined significantly after a high-severity fire (complete tree mortality) but not after a low-severity fire (no tree mortality), despite substantial losses of the organic layer. Tree root respiration is thus key in determining post-fire soil CO2 emissions and may benefit, along with heterotrophic respiration, from the nutrient pulse after a low-severity fire. Salvage-logging after a high-severity fire had no significant effects on soil carbon fluxes, microclimate or nutrient content compared with leaving the dead trees standing, although differences are expected to emerge in the long term. In contrast, the impact of stand age was substantial: a young burnt stand experienced more extreme microclimate, lower soil nutrient supply and significantly lower soil respiration than a mature burnt stand, due to a thinner organic layer and the decade-long effects of a previous clear-cut and soil scarification. Disturbance history and burn severity are, therefore, important factors for predicting changes in the boreal forest carbon sink after wildfires. The presented short-term effects and ongoing monitoring will provide essential information for sustainable management strategies in response to the increasing risk of wildfire

Beyond the martial façade: gender, heritage and medieval castles

Gendered interpretations are rare both within castle-studies and heritage discourses on medieval castles. Yet, castles hold potential to inform multi-vocal accounts of the medieval past and to inspire meaningful heritage interpretations to achieve greater societal impact. This article explores the role that gender currently plays in interpretations of medieval castles in Britain, supported by three case-studies written by heritage professionals. The enduring narrative of militarism at medieval castles sites is discussed, together with issues of authenticity in relation to the historical record, which is in itself biased and inherently gendered. Outcomes from a collaborative workshop highlight the need to address interpretative issues where gender is considered to equate to ‘making women visible’. Finally, we pose the question: What makes a ‘good gendered interpretation’ at a public heritage site