174 research outputs found

    Creating Structure in Web Archives With Collections: Different Concepts From Web Archivists

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    As web archives' holdings grow, archivists subdivide them into collections so they are easier to understand and manage. In this work, we review the collection structures of eight web archive platforms: : Archive-It, Conifer, the Croatian Web Archive (HAW), the Internet Archive's user account web archives, Library of Congress (LC), PANDORA, Trove, and the UK Web Archive (UKWA). We note a plethora of different approaches to web archive collection structures. Some web archive collections support sub-collections and some permit embargoes. Curatorial decisions may be attributed to a single organization or many. Archived web pages are known by many names: mementos, copies, captures, or snapshots. Some platforms restrict a memento to a single collection and others allow mementos to cross collections. Knowledge of collection structures has implications for many different applications and users. Visitors will need to understand how to navigate collections. Future archivists will need to understand what options are available for designing collections. Platform designers need it to know what possibilities exist. The developers of tools that consume collections need to understand collection structures so they can meet the needs of their users.Comment: 5 figures, 16 pages, accepted for publication at TPDL 202

    Quantum dynamics of a model for two Josephson-coupled Bose--Einstein condensates

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    In this work we investigate the quantum dynamics of a model for two single-mode Bose--Einstein condensates which are coupled via Josephson tunneling. Using direct numerical diagonalisation of the Hamiltonian, we compute the time evolution of the expectation value for the relative particle number across a wide range of couplings. Our analysis shows that the system exhibits rich and complex behaviours varying between harmonic and non-harmonic oscillations, particularly around the threshold coupling between the delocalised and self-trapping phases. We show that these behaviours are dependent on both the initial state of the system as well as regime of the coupling. In addition, a study of the dynamics for the variance of the relative particle number expectation and the entanglement for different initial states is presented in detail.Comment: 15 pages, 8 eps figures, accepted in J. Phys.

    Nutrient risk assessment in a decision theoretic context

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    Abstract Background. This study describes a decision-theoretic approach to nutrient assessment based on Bayesian methods, which can be used to give accurate estimates of optimum intakes. Analysis of risk is an incomplete technique for dealing with nutrients and other substances that, by definition, have an associated benefit. Results. This paper shows that the risk analysis methods being developed by the Codex Commission on Nutrition and European Food Safety Authority, among others, are inappropriate for assessing safe nutrient intake levels. Decision theoretic methods incorporate benefits associated with these essential nutrients, as well as potential risk. Conclusion. These methods allow for missing or incomplete data, which conventional risk analysis does not

    Chaste: a test-driven approach to software development for biological modelling

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    Chaste (‘Cancer, heart and soft-tissue environment’) is a software library and a set of test suites for computational simulations in the domain of biology. Current functionality has arisen from modelling in the fields of cancer, cardiac physiology and soft-tissue mechanics. It is released under the LGPL 2.1 licence.\ud \ud Chaste has been developed using agile programming methods. The project began in 2005 when it was reasoned that the modelling of a variety of physiological phenomena required both a generic mathematical modelling framework, and a generic computational/simulation framework. The Chaste project evolved from the Integrative Biology (IB) e-Science Project, an inter-institutional project aimed at developing a suitable IT infrastructure to support physiome-level computational modelling, with a primary focus on cardiac and cancer modelling

    Constellations of identity: place-ma(r)king beyond heritage

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    This paper will critically consider the different ways in which history and belonging have been treated in artworks situated in the Citadel development in Ayr on the West coast of Scotland. It will focus upon one artwork, Constellation by Stephen Hurrel, as an alternative to the more conventional landscapes of heritage which are adjacent, to examine the relationship between personal history and place history and argue the primacy of participatory process in the creation of place and any artwork therein. Through his artwork, Hurrel has attempted to adopt a material process through which place can be created performatively but, in part due to its non-representational form, proves problematic, aesthetically and longitudinally, in wholly engaging the community. The paper will suggest that through variants of ‘new genre public art’ such as this, personal and place histories can be actively re-created through the redevelopment of contemporary urban landscapes but also highlight the complexities and indeterminacies involved in the relationship between artwork, people and place

    American Society of Clinical Oncology/College ofAmerican Pathologists guideline recommendations forimmunohistochemical testing of estrogen andprogesterone receptors in breast cancer

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    Purpose: To develop a guideline to improve theaccuracy of immunohistochemical (IHC) estrogen receptor(ER) and progesterone receptor (PgR) testing in breastcancer and the utility of these receptors as predictivemarkers.Methods: The American Society of Clinical Oncologyand the College of American Pathologists convened aninternational Expert Panel that conducted a systematicreview and evaluation of the literature in partnership withCancer Care Ontario and developed recommendations foroptimal IHC ER/PgR testing performance.Results: Up to 20% of current IHC determinations ofER and PgR testing worldwide may be inaccurate (falsenegative or false positive). Most of the issues with testinghave occurred because of variation in preanalyticvariables, thresholds for positivity, and interpretationcriteria.Recommendations: The Panel recommends that ER andPgR status be determined on all invasive breast cancers andbreast cancer recurrences. A testing algorithm that relieson accurate, reproducible assay performance is proposed.Elements to reliably reduce assay variation are specified. It is recommended that ER and PgR assays be consideredpositive if there are at least 1% positive tumor nuclei in the sample on testing in the presence of expected reactivity of internal (normal epithelial elements) and external controls. The absence of benefit from endocrine therapy for women with ER-negative invasive breast cancers has been confirmed in large overviews of randomized clinical trials.(Arch Pathol Lab Med. 2010;134:907–922
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