466 research outputs found

    Official Knowledge: Validation Mechanisms for Knowledge Management Systems

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    One of the most important roles of a knowledge management system is as a filter to verify, authenticate, or justify the knowledge of an organization. The knowledge that passes this filter and is retained or otherwise deemed valuable by the system is official knowledge, the knowledge sanctioned by an organization. In this study, twenty-two articles that describe typologies of knowledge management systems were reviewed for their insights into knowledge validation. The articles were reviewed in the context of intellectual parentage with each article belonging to one of ten lines of inquiry spawning from five preeminent knowledge management articles. The results of this metastudy identify epistemology, knowledge transfer, the application environment, and the social process of sensemaking as valuable considerations for the design of validation mechanisms. A checklist of these considerations serves as the primary contribution of this study. Implications for future work in the design of validation mechanisms for knowledge management systems are discussed

    Using RDF to Model the Structure and Process of Systems

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    Many systems can be described in terms of networks of discrete elements and their various relationships to one another. A semantic network, or multi-relational network, is a directed labeled graph consisting of a heterogeneous set of entities connected by a heterogeneous set of relationships. Semantic networks serve as a promising general-purpose modeling substrate for complex systems. Various standardized formats and tools are now available to support practical, large-scale semantic network models. First, the Resource Description Framework (RDF) offers a standardized semantic network data model that can be further formalized by ontology modeling languages such as RDF Schema (RDFS) and the Web Ontology Language (OWL). Second, the recent introduction of highly performant triple-stores (i.e. semantic network databases) allows semantic network models on the order of 10910^9 edges to be efficiently stored and manipulated. RDF and its related technologies are currently used extensively in the domains of computer science, digital library science, and the biological sciences. This article will provide an introduction to RDF/RDFS/OWL and an examination of its suitability to model discrete element complex systems.Comment: International Conference on Complex Systems, Boston MA, October 200

    Grammar-Based Geodesics in Semantic Networks

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    A geodesic is the shortest path between two vertices in a connected network. The geodesic is the kernel of various network metrics including radius, diameter, eccentricity, closeness, and betweenness. These metrics are the foundation of much network research and thus, have been studied extensively in the domain of single-relational networks (both in their directed and undirected forms). However, geodesics for single-relational networks do not translate directly to multi-relational, or semantic networks, where vertices are connected to one another by any number of edge labels. Here, a more sophisticated method for calculating a geodesic is necessary. This article presents a technique for calculating geodesics in semantic networks with a focus on semantic networks represented according to the Resource Description Framework (RDF). In this framework, a discrete "walker" utilizes an abstract path description called a grammar to determine which paths to include in its geodesic calculation. The grammar-based model forms a general framework for studying geodesic metrics in semantic networks.Comment: First draft written in 200

    Predictors of Burnout in Public Library Employees

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    Work stress and professional burnout are recognized as concerns for public library employees, yet little research has been conducted. The purpose of the current study was to better understand burnout and the contributing factors in a state-wide sample of public library employees in Indiana. Using a web-based survey, 171 employees of public libraries reported their level of burnout (emotional exhaustion, cynicism, and professional efficacy; Maslach Burnout Inventory-General Survey) and potential predictors, including levels of autonomy, co-worker support, work pressure, technology attitudes, and recovery experiences. A subset of 70 completed the burnout measures twice, allowing for predictions of change over time. Most predictors were correlated with burnout cross-sectionally, except for technology attitudes. Emotional exhaustion was positively associated with work pressure, and negatively associated with autonomy, role clarity, coworker support, and recovery experiences of relaxation, mastery, and control. Similar patterns were found for cynicism and reduced efficacy. However, over a period of approximately six months, only role clarity predicted decreased burnout (emotional exhaustion) above prior levels of burnout

    Proinsulin and heat shock protein 90 as biomarkers of beta-cell stress in the early period after onset of type 1 diabetes

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    Rapid evaluation of therapies designed to preserve β cells in persons with type 1 diabetes (T1D) is hampered by limited availability of sensitive β-cell health biomarkers. In particular, biomarkers elucidating the presence and degree of β-cell stress are needed. We characterized β-cell secretory activity and stress in 29 new-onset T1D subjects (10.6 ± 3.0 years, 55% male) at diagnosis and then 8.2 ± 1.2 weeks later at first clinic follow-up. We did comparisons with 16 matched healthy controls. We evaluated hemoglobin A1c (HbA1c), β-cell function (random C-peptide [C] and proinsulin [PI]), β-cell stress (PI:C ratio), and the β-cell stress marker heat shock protein (HSP)90 and examined these parameters' relationships with clinical and laboratory characteristics at diagnosis. Mean diagnosis HbA1c was 11.3% (100 mmol/mol) and 7.6% (60 mmol/mol) at follow-up. C-peptide was low at diagnosis (P < 0.001 vs controls) and increased at follow-up (P < 0.001) to comparable with controls. PI did not differ from controls at diagnosis but increased at follow-up (P = 0.003) signifying increased release of PI alongside improved insulin secretion. PI:C ratios and HSP90 concentrations were elevated at both time points. Younger subjects had lower C-peptide and greater PI, PI:C, and HSP90. We also examined islets isolated from prediabetic nonobese diabetic mice and found that HSP90 levels were increased ∼4-fold compared with those in islets isolated from matched CD1 controls, further substantiating HSP90 as a marker of β-cell stress in T1D. Our data indicate that β-cell stress can be assessed using PI:C and HSP90. This stress persists after T1D diagnosis. Therapeutic approaches to reduce β-cell stress in new-onset T1D should be considered

    Two contemporaneous mitogenomes from terminal Pleistocene burials in eastern Beringia

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    Pleistocene residential sites with multiple contemporaneous human burials are extremely rare in the Americas. We report mitochondrial genomic variation in the first multiple mitochondrial genomes from a single prehistoric population: two infant burials (USR1 and USR2) from a common interment at the Upward Sun River Site in central Alaska dating to ~11,500 calendar years before present (cal B.P.). Using a targeted capture method and next-generation sequencing we determined that the USR1 infant possessed variants that define mitochondrial lineage C1b, while the USR2 genome falls at the root of lineage B2, allowing us to refine younger coalescence age estimates for these two clades. C1b and B2 are rare to absent in modern populations of Northern North America. Documentation of these lineages at this location in the Late Pleistocene provides evidence for the extent of mitochondrial diversity in early Beringian populations, which supports the expectations of the Beringian Standstill Model

    A Transdisciplinary Approach to Determining the Provenience of a Distorted, Pre-Columbian Skull Recovered in Rural Idaho

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    Transdisciplinary research involves cooperation, exchange of information, sharing of resources and integration of disciplines to achieve a common scientific goal. In this study, collaborators utilized tools and knowledge of materials science, anthropology, archaeology, geosciences and biology in an attempt to determine the provenience of skeletal remains of unknown origin. The exchange of ideas and skills along with the crossing of disciplines in this study sucessfully allowed the incorporation of expertise from many team members. This transdisciplinary approach to research provided a more comprehensive and detailed analysis than any one field alone could provide. An archaeological assessment of a human skull recovered in rural Idaho recognized cranial deformation and post-mortem application of a red pigment. A combination of scanning electron microscopy (SEM), x-ray fluorescence (XRF) and energy-dispersive x-ray spectroscopy (EDS) identified the major and trace elements present in the red post-mortem pigment as cinnabar and rare earth metals. Analysis via carbon and oxygen stable isotopes from teeth and bone to provided insight into the diet and habitat for distinct segments of the individual’s life, indicating a regional separation in early life versus late adulthood. Radiocarbon dating determined the approximate age of the skull to be between 600-700 years old and a forensic mtDNA assessmentcategorized a mitochondrial haplogroup for the remains as originating from the East African or Arabian Peninsula

    Recruitment and representativeness of blood donors in the INTERVAL randomised trial assessing varying inter-donation intervals.

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    BACKGROUND: The interpretation of trial results can be helped by understanding how generalisable they are to the target population for which inferences are intended. INTERVAL, a large pragmatic randomised trial of blood donors in England, is assessing the effectiveness and safety of reducing inter-donation intervals. The trial recruited mainly from the blood service's static centres, which collect only about 10 % of whole-blood donations. Hence, the extent to which the trial's participants are representative of the general blood donor population is uncertain. We compare these groups in detail. METHODS: We present the CONSORT flowchart from participant invitation to randomisation in INTERVAL. We compare the characteristics of those eligible and consenting to participate in INTERVAL with the general donor population, using the national blood supply 'PULSE' database for the period of recruitment. We compare the characteristics of specific groups of trial participants recruited from different sources, as well as those who were randomised versus those not randomised. RESULTS: From a total of 540,459 invitations, 48,725 donors were eligible and consented to participate in INTERVAL. The proportion of such donors varied from 1-22 % depending on the source of recruitment. The characteristics of those consenting were similar to those of the general population of 1.3 million donors in terms of ethnicity, blood group distribution and recent deferral rates from blood donation due to low haemoglobin. However, INTERVAL participants included more men (50 % versus 44 %), were slightly older (mean age 43.1 versus 42.3 years), included fewer new donors (3 % versus 22 %) and had given more donations over the previous 2 years (mean 3.3 versus 2.2) than the general donor population. Of the consenting participants, 45,263 (93 %) donors were randomised. Compared to those not randomised, the randomised donors showed qualitatively similar differences to those described above. CONCLUSIONS: There was broad similarity of participants in INTERVAL with the general blood donor population of England, notwithstanding some differences in age, sex and donation history. Any heterogeneity of the trial's results according to these characteristics will need to be studied to ensure its generalisability to the general donor population. TRIAL REGISTRATION: Current Controlled Trials ISRCTN24760606 . Registered on 25 January 2012.The trial is funded by NHS Blood and Transplant. The trial’s coordinating centre at the Department of Public Health and Primary Care at the University of Cambridge has received core support from the UK Medical Research Council, the British Heart Foundation and the UK National Institute of Health Research (Cambridge Biomedical Research Centre). Investigators at the University of Oxford have been supported by the Research and Development Programme of NHSBT, the NHSBT Howard Ostin Trust Fund, the UK National Institute of Health Research (Oxford Biomedical Research Centre) through the programme grant NIHR-RP-PG-0310-1004 and the Oxford Biomedical Research Centre.This is the final version of the article. It first appeared from BioMed Central via http://dx.doi.org/10.1186/s13063-016-1579-
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