28 research outputs found

    Unsupervised Terminological Ontology Learning based on Hierarchical Topic Modeling

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    In this paper, we present hierarchical relationbased latent Dirichlet allocation (hrLDA), a data-driven hierarchical topic model for extracting terminological ontologies from a large number of heterogeneous documents. In contrast to traditional topic models, hrLDA relies on noun phrases instead of unigrams, considers syntax and document structures, and enriches topic hierarchies with topic relations. Through a series of experiments, we demonstrate the superiority of hrLDA over existing topic models, especially for building hierarchies. Furthermore, we illustrate the robustness of hrLDA in the settings of noisy data sets, which are likely to occur in many practical scenarios. Our ontology evaluation results show that ontologies extracted from hrLDA are very competitive with the ontologies created by domain experts

    Cleaning ability and induced dentin loss of a magnetostrictive ultrasonic instrument at different power settings

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    Some laboratory studies have evaluated the oscillation mode of ultrasonic scalers. None of them recorded its influence on calculus removal and quantified dental hard tissue loss. This study aimed to compare the performance of a magnetostrictive ultrasonic instrument at different power settings in vitro in relation to the tip oscillation activity. The oscillation activity of the straight Slimline® insert in the Cavitron® ultrasonic scaling device was analyzed at five different power settings with the help of two laser vibrometers. The performance of this instrument was tested on 60 roots of human single-rooted teeth. Twelve roots each were randomly assigned to be instrumented at a given power setting. Every root was instrumented for 120s at a standardized instrumentation force of 0.1 ± 0.05N. In addition, another 30 periodontally involved roots with subgingival calculus were instrumented accordingly to assess the calculus removal potential. The surface characteristics after instrumentation were analyzed under scanning electron microscope. The instrumentation at minimum power setting resulted in an mean increase of the root surface roughness of 0.18 ± 0.28 compared to 0.51 ± 0.48 at maximum power setting (P = 0.0327). The loss of dental hard tissue amounted to 11.37 ± 3.64 at minimum compared to 23.37 ± 15.76 at maximum power (P = 0.0010). The higher the power setting, the more calculus was removed. The values of the latter ranged between 4.04 ± 1.87 and 11.26 ± 4.66mm2 of cleaned dentin surface area (P = 0.0065). At lower power settings, a more favorable relation between cleaning ability, loss of dentine, and surface roughness was foun

    Beyond procedure's content: Cognitive subjective experiences in procedural justice judgments

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    Procedural justice concerns play a critical role in economic settings, politics, and other domains of human life. Despite the vast evidence corroborating their relevance, considerably less is known about how procedural justice judgments are formed. Whereas earlier theorizing focused on the systematic integration of content information, the present contribution provides a new perspective on the formation of justice judgments by examining the influence of accessibility experiences. Specifically, we hypothesize that procedural justice judgments may be formed based on the ease or difficulty with which justice-relevant information comes to mind. Three experiments corroborate this prediction in that procedures were evaluated less positively when the retrieval of associated unfair aspects was easy compared to difficult. Presumably this is because when it feels easy (difficult) to retrieve unfair aspects, these are perceived as frequent (infrequent), and hence the procedure as unjust (just). In addition to demonstrating that ease-of-retrieval may influence justice judgments, the studies further revealed that reliance on accessibility experiences is high in conditions of personal certainty. We suggest that this is because personal uncertainty fosters systematic processing of content information, whereas personal certainty may invite less taxing judgmental strategies such as reliance on ease-of-retrieval

    Shaping Cooperation Behavior: The Role of Accessibility Experiences

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    The present research investigates the influence on cooperative behavior of accessibility experiences associated with the retrieval of fairness-relevant information from memory. We argue that the decision whether to cooperate in negotiations depends not only on information about the appropriateness of the negotiation procedure, but also on the experience of how difficult or easy it is to come up with this information. Supporting this hypothesis, it is shown that in the context of a bargaining experiment, participants' experiences of ease or difficulty in retrieving unfair aspects of the respective negotiation procedure strongly influence their cooperation behavior. In addition, we hypothesize and empirically substantiate that the influence of accessibility experiences on cooperation behavior occurs particularly in situations of certainty salience. Implications for future research on cooperation and on accessibility experiences are discussed

    Consumer Response to Drug Risk Information:The Role of Positive Affect

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    Risk disclosure is an essential element of the marketing of prescription drugs and other medical products. This study examines how consumers respond to verbal information about the frequency and severity of medical-product risks and how media-induced affect can moderate such responses. The study finds that consumers tend to overestimate the actual likelihood of adverse events described with words such as “common” or “rare” (compared with the probabilities such terms are typically intended to convey) and that consumers tend to give little weight to such probability language when forming product use intentions. However, consumers in positive media-induced moods seem to engage in more nuanced evaluation of product risk information, weighing both frequency and severity information and using such information to make inferences about other product attributes (e.g., product efficacy). These findings suggest that medical marketers and regulators need to devise more effective means of communicating risk probability to consumers and that positive mood induction (e.g., by placing advertisements in upbeat media environments) can enhance consumers' ability to process product risk information

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Automated Knowledge Source Selection and Service Composition in Manufacturing

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    207 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2004.The application scope of this research is the manufacturing domain and a comprehensive manufacturing case study is presented.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD
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