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11.
Andreas Angourakis José Ignacio Santos José Manuel Galán Andrea L. Balbo 《Environmental Archaeology》2015,20(4):349-363
AbstractA consistent access to food is paramount for humans at individual and group level. Besides providing the basic nutritional needs, access to food defines social structures and has stimulated innovation in food procurement, processing and storage. We focus on the social aspects of food storage, namely the role of cooperation for the emergence and maintenance of common stocks. Cooperative food stocks are examined here as a type of common-pool resource, where appropriators must cooperate to avoid shortage (i.e. the tragedy of commons). ‘Food for all’ is an agent-based model in which agents face the social dilemma of whether or not to store in a cooperative stock, adapting their strategies through a simple reinforcement learning mechanism. The model provides insights on the evolution of cooperation in terms of storage efficiency and considering the presence of social norms that regulate reciprocity. For cooperative food storage to emerge and be maintained, a significant dependency on the stored food and some degree of external pressure are needed. In fact, cooperative food storage emerges as the best performing strategy when facing environmental stress. Likewise, an intermediate control over reciprocity favours cooperation for food storage, suggesting that concepts of closed reciprocity are precursors to cooperative stocks, while excess control over reciprocity is detrimental for such institution. 相似文献
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Alfred J. Andrea 《The Historian; a journal of history》1996,58(4):931-937
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Active learning is increasingly promoted within institutions of higher education to assist students develop higher order thinking and link knowledge to meaning. In this paper, the authors evaluate the use of weekly online quizzes based on prescribed preparatory material as a tool to incentivize preparatory reading in order to enable and encourage active learning. The study is based on mixed data sources, including three years of student-evaluation data, to understand student perceptions of the role and value of online quizzes. The study shows a high level of student engagement with the quizzes and positive assessment of their role in encouraging the completion of prescribed reading. Online quizzes were found to be an effective mechanism for incentivizing student completion of preparatory work, enhancing active learning (such as through in-class discussions), and were relatively time efficient from the perspective of the educator. 相似文献
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Gabor Thomas Aleks Pluskowski Roberta Gilchrist Guillermo García-Contreras Ruiz Anders Andrén Andrea Augenti 《Medieval archaeology》2017,61(2):300-329
UNDERSTANDING RELIGIOUS CHANGE between the collapse of the Roman Empire and the Reformation forms one of the cornerstones of medieval archaeology, but has been riven by period, denominational, and geographical divisions. This paper lays the groundwork for a fundamental rethink of archaeological approaches to medieval religions, by adopting an holistic framework that places Christian, pagan, Islamic and Jewish case studies of religious transformation in a long-term, cross-cultural perspective. Focused around the analytical themes of ‘hybridity and resilience’ and ‘tempo and trajectories’, our approach shifts attention away from the singularities of national narratives of religious conversion, towards a deeper understanding of how religious beliefs, practices and identity were renegotiated by medieval people in their daily lives. 相似文献
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Zoos and aquariums are responding to the worldwide biodiversity crisis through major conservation initiatives like captive breeding for assurance populations and reintroduction programs. These institutions also fundraise, offer education programs, and provide critical research on biodiversity. Through a case study inside three accredited Canadian zoos, this paper illustrates that zoos and their staff members are being incorporated into many official species‐at‐risk recovery efforts on provincial, federal, and international levels. Specifically, the zoos studied are involved in every stage of the recovery process, from providing valuable research and habitat analyses, to captive breeding animals for reintroduction, to writing recovery strategies and creating recovery policy for multiple jurisdictional levels. Zoo staff indicate that zoos are uniquely suited to conservation because zoos have space, expertise, apolitical status, and the ability to connect with the public. Overall, the paper suggests that zoos can significantly contribute to species‐at‐risk protection and recovery in Canada and beyond. 相似文献
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Identification of Suitable Limit States from Nonlinear Dynamic Analyses of Masonry Structures 总被引:1,自引:0,他引:1
Amaryllis Mouyiannou Andrea Penna Guido Magenes 《Journal of Earthquake Engineering》2014,18(2):231-263
Performance-based earthquake engineering, developed over the last decades for the design and assessment of other structures, can also be applied for masonry structures if the particularities of masonry are incorporated into the procedure. According to this methodology, structural performance can be assessed according to damage states which are identified through displacement/damage indicators. While various methods for the identification of limit states from the results of nonlinear static analyses exist, the identification of damage states from the results of nonlinear dynamic analyses is still uncertain. This article investigates a number of criteria allowing to identify the attainment of significant limit states from the results of time history analyses, in terms of appropriately identified response quantities. These criteria are applied to five building prototypes and their results are compared. A comparison with the limit states derived from nonlinear static analyses is also made. 相似文献
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Daniela Heil Gaynor Macdonald 《Oceania; a journal devoted to the study of the native peoples of Australia, New Guinea, and the Islands of the Pacific》2008,78(3):299-319
ABSTRACT The authors have worked in Australian Aboriginal communities within the Wiradjuri area of central‐western New South Wales. Examining what appear to be distinctive Aboriginal approaches to time, we argue that these stem not from a different notion of time as such but, rather, from the relationship between the social and the self which places a distinctive value on the use and management of time. One way to access the dynamic between time and self is to realise that life is understood as fluid and contingent rather than predictable. This continually subverts the idea that time is measurable and controllable; that life is lived within domesticated sedentary space; and that planning ahead and self‐discipline are virtues. Yet these are notions central to practices associated with contemporary health care. A majority of health care providers, whether Aboriginal or not, are trained in the Australian mainstream health system and may consequently underestimate the implications of different ways in which a person acts on the temporal/spatial dimensions of her life, and how this influences ways in which she manages time in relation to her health and well‐being. Temporal concepts, such as ‘planning’, ‘discipline’, ‘future’, ‘boredom’, or ‘patience’, as well as that of the ‘long‐term’ with regard to managing illness or money, interact with the ways in which Aboriginal people experience themselves as ill or in need of health care, influencing how they act on medical advice. We argue that the key to understanding the use of time lies not in the concept of time per se but in what is involved in developing a responsive social self when the time/space dimensions of the day to day are informed by a fluid and thus contingent ontology of that day to day. 相似文献
20.
Paola Boscato Christian Carioni Andrea Brandolini Laura Sadori Mauro Rottoli 《Journal of archaeological science》2008
The persistent uncertainty on the classification of the “new” glume wheat found in Neolithic and Bronze Age sites from Greece and other European settlements might be resolved only through analysis of its ancient DNA. Tools able to discriminate among different Triticum species on the basis of scarce, very damaged DNA, are therefore essential. While current attempts concentrate on DNA fragments sequencing and comparison, in some instances PCR-based selective amplification techniques might offer a cheaper and quicker alternative. The purpose of this research was therefore the identification of species-specific primers, able to distinguish caryopses of Triticum timopheevii subsp. timopheevii from those of Triticum turgidum subsp. dicoccum. Primers and their working conditions were defined and optimized using DNA from modern accessions. The ribosomal primers ITS1 tim and ITS2 tim, and the nuclear primer acetyl-coenzyme A tim clearly discriminated the sequences of Triticum timopheevii from other species. Finally, Neolithic charred wheat grains found in the sites of Sammardenchia (Pozzuolo del Friuli, Udine) and La Marmotta (Lago di Bracciano, Roma), belonging to the “new” wheat type or to emmer, were tested with the three selected primers. However, the results were not conclusive, because the samples analysed were apparently too degraded to yield useful DNA. 相似文献