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Examines participants' confidence in their judgments of the relevance of bibliographic records to particular research questions. Empirical investigation of the association between judges' confidence and the number of categories for a relevance rating scale; Optimal scale for maximizing confidence in relevance judgments.

Details two studies that aim to determine if scores on science process skills and general reasoning ability tests will be associated with success in the Science Olympiad for high school students. Test of Integrated Process Skills (TIPS); Group Assessment of Logical Thinking (GALT) test; Olympiad as a day-long series of events designed to foster academic competition in activity-based science.

The presence of clustering structure in the cystic fibrosis (CF) Document Collection is evaluated as a function of the exhaustivity of five composite representations. The composite representations are constructed from two subject descriptions, based on Medical Subject Headings and subheadings, and two citation indexes, based on the complete set of references in and a comprehensive set of citations to each document. Experimental results reveal observable evidence for clustering structure at all exhaustivity levels of all composite representations but also show that the evidence for clustering structure diminishes as the exhaustivity of each representation is decreased. The representation composed of references and citations shows less evidence of clustering structure at the exhaustive level but more uniform evidence of clustering structure over a wide range of exhaustivity levels than composite representations that include subject descriptions. The structures imposed on the CF Document Collection by all composite representations satisfy the necessary condition for a meaningful clustering outcome. [ABSTRACT FROM AUTHOR]

Measures of cluster-based retrieval effectiveness are computed for five composite representations in the cystic fibrosis (CF) Document Collection. The composite representations are constructed from combinations of two subject representations, based on Medical Subject Headings and subheadings, and two citation representations, consisting of the complete list of cited references and a comprehensive list of citations for each document. Experimental retrieval results are presented as a function of the exhaustivity and similarity of the composite representations and reveal consistent patterns from which optimal performance levels can be identified. The optimal performance values provide an assessment of the absolute capacity of each composite representation to associate documents relevant to the same query and discriminate between documents relevant to different queries in single-link hierarchies. The optimal performance values for all composite representations are completely comparable and are superior to the optimal performance of constituent representations. Optimal performance consistently occurs at tow levels of exhaustivity. Exhaustive composite representations that include subject descriptions produce the lowest levels of performance; retrieval results derived from random structures are comparable to the observed results. The effectiveness of the exhaustive representation composed of references and citations is materially superior to the effectiveness of exhaustive composite representations that include subject descriptions. [ABSTRACT FROM AUTHOR]

The structure of coauthor graphs and the statistical validity of the associated author partitions are investigated as a function of productivity and collaborative thresholds. The productivity threshold determines the number of authors (points) in a coauthor graph, and the collaborative threshold determines the number of coauthor pairs (lines) in the graph. The statistical validity of author partitions is determined by the random-graph hypothesis. The results show that for "small" databases, statistically preferred partitions occur when all authors and coauthor pairs appear in the graph. For 'large" databases, statistically preferred partitions occur when authors and coauthor pairs who publish only one article are excluded from the graph. Unlike other bibliometric relationships, the highly selective nature of the collaborative relationship produces a wide range of threshold values for which the associated partitions are statistically valid. It remains to be shown how the statistical validity of partitions is related to the empirical significance of the same partitions. [ABSTRACT FROM AUTHOR]

Using the Random Graph Hypothesis, the statistical validity of co-citation graphs has been investigated as a function of co-citation strength for a given value of citation frequency. The results show that for both high and low values of co-citation strength the partition of cited documents produced by the co-citation relationship may be statistically invalid. Critical thresholds can be identified that define the limits of statistical validity. Within these limits, there is a narrow region of statistical validity where the associated structures are not an artifact of the clustering procedure and can be interpreted. It is concluded that the choice of citation and co-citation thresholds can be influenced by formal considerations which insure statistically meaningful partitions rather than arbitrary decisions which can produce meaningless interpretations. Experimental and theoretical implications for the co-citation graph and other bibliometric structures are discussed. [ABSTRACT FROM AUTHOR]

The lines of a co-author graph represent channels of communication through which Information has been and may continue to be Informally exchanged. The Brillouin information Measure can be used to describe Important properties of the co-author graph and other communication-graphs. The "connectedness" of a graph can be represented on a scale In which one limiting value signifies a connected graph and the other limiting value signifies a graph in which all points are isolated. Important points can be distinguished from all other points in a communication-graph. These important points are defined mathematically and are called synthetic cutpoints. A measure of importance can be assigned to each point In a communication-graph. This measure can be used to order points In terms of their contribution to a favorable communication-structure. [ABSTRACT FROM AUTHOR]

An existing model of the circulation subsystem of a library has been modified to explicitly include renewals and to describe a semester loan policy. An extensive amount of experimental data have been obtained by recording the history of all books which circulated from Sears Library at Case Western Reserve University during the fall semester, 1973. These data, which characterize various aspects of user behavior, in combination with a numerical statement of the loan policy of the library serve as input parameters for the model which simulates the events that occur in the circulation subsystem. The results of the simulation provide information about the availability of books and the delay associated with recalls. These results have been compared to experimental observation. The agreement between the predicted values and the experimental observation is good. Thus the validity of the model is demonstrated, and the model is used to simulate various alternative loan policies. The effect of these alternatives on book availability is also given. [ABSTRACT FROM AUTHOR]

In this article the derivation of a general retrieval effectiveness measure is investigated. It is shown that the measure cannot be justified on the basis of formal considerations associated with measurement theory. The implications of the mathematical condition which defines the relative importance a user assigns to precision and recall are also investigated. Inconsistencies in the definition of the associated weight are resolved, and it is shown that the influence of the weight on the effectiveness measure can produce counterintuitive results. An alternative effectiveness measure provided by the MZ-metric is recommended. [ABSTRACT FROM AUTHOR]

Introduction and Aim: Problem drinking is rarely identified unless health-care professionals are specifically instructed to assess alcohol consumption. Individualised web-based alcohol interventions provide opportunities to enhance screening and early identification. We aimed to create a web-based brief personalised feedback intervention to enable client-centred screening and self-referral by problem drinkers recently admitted to hospital., Design and Methods: To increase transparency of the development process, this short report describes the theoretical underpinnings and development of ChangeDrinking including identification of needs and matching with resources, screening tool selection, and look and feel., Results: The website structure and content was modelled on motivational dialogue. ChangeDrinking is closely coupled to an independent questionnaire management system; this architecture enables internal logic to allow branching based on dynamic user inputs. The motivational underpinnings led to development of personalised predetermined dialogue with strong theory-practice links. Applying principles of conveying empathy and reflection was challenging within the confines of a predetermined dialogue. Reflective listening in ChangeDrinking does not extend to inviting statements of resistance to be entered., Discussion and Conclusions: ChangeDrinking has become an optional component of routine treatment for patients with an alcohol-related admission in two large UK National Health Service general hospitals., (© 2014 Australasian Professional Society on Alcohol and other Drugs.)

Background: This study examines the impact of donor liver macrovesicular steatosis on recurrence of hepatitis C virus (HCV) disease after liver transplantation., Methods: Between 1998 and 2004, 113 patients underwent liver transplantation for HCV-related cirrhosis. Time to histologic recurrence (fibrosis score >or=2) was the primary endpoint of the study. Recurrence was graded according to the system of Ludwig and Batts. A Cox's proportional hazard regression model was used to analyse the association between donor liver steatosis and HCV recurrence., Results: Recurrence-free survival for patients who received steatotic grafts was 82% and 47% at 1 and 4 years, respectively, and 81% and 52% for patients who received a non-steatotic liver. Donor macrovesicular steatosis (5-45%) was found to have no impact on HCV recurrence (P=0.47). Donor age (P=0.02) and cold ischaemia time (P=0.01) were found to increase the relative risk of HCV recurrence. The estimated risk of HCV recurrence increased by 23% for every 10-year increase in donor age. Similarly the risk of recurrence increased by 13% for every 1-h increase in cold ischaemia time., Conclusion: Mild-moderate donor liver macrovesicular steatosis has no impact on HCV recurrence after liver transplantation for HCV-related cirrhosis. Cold ischaemia time and donor age increased the likelihood of HCV recurrence.

Imipramine, a widely used antidepressant, has rarely been associated with hepatic abnormalities. In the majority of reported cases, hepatic effects have been transient and readily reversible on discontinuation of the drug. We cared for an 11-year-old boy with hepatic failure and massive cell necrosis which followed treatment with imipramine for enuresis. This therapy led to fulminant hepatic failure and subsequent liver transplantation.

We cared for a 4-year-old patient who had undergone orthotopic liver transplantation and was placed on a ventilator for respiratory distress associated with Pneumocystis carinii pneumonia. The neuromuscular blocking agent pancuronium bromide 1.0-1.2 mg every hour as needed was used to facilitate artificial ventilation for 40 days. On discontinuation of pancuronium, the patient experienced severe, generalized neuromuscular dysfunction. Because no improvement was seen for 2 weeks, the acetylcholinesterase inhibitors edrophonium and pyridostigmine were instituted. Shortly thereafter the patient's condition began to improve. Gradual improvement occurred over 3-4 months and the patient has since returned to baseline neurologic function. We suggest that long-term pancuronium use was the cause of the patient's prolonged paralysis. The improvement experienced after the initiation of antidotal therapy strongly supports our proposal.

Ten healthy male volunteers were given 200 mg p.o. of isoxicam after an overnight fast and the plasma concentrations over time followed for 96 h by h.p.l.c. Five days later enteric coated acetylsalicylic acid (ASA) 650 mg four times daily was started and continued for 10 days producing steady state trough plasma salicylate of 83 mg/l (range 21-133). A second 200 mg isoxicam dose was given 5 days after starting ASA and the plasma concentration time-curve again followed. After ASA, there was no change in lag time (0.54 vs 0.51 h), time to peak concentration (10 vs 10 h), or disappearance t1/2 (28.7 vs 31.0 h) however the peak isoxicam concentration and AUC were reduced 18 and 22% respectively (P less than 0.01). Plasma protein binding of isoxicam studied by equilibrium dialysis was 96 +/- 1% in the absence and 86 +/- 5% in the presence of ASA. The reduction in binding was unrelated to plasma SA concentrations achieved or observed reductions in AUC for plasma isoxicam. ASA decreased plasma isoxicam binding, peak plasma isoxicam concentrations and AUC without altering the apparent disappearance half-life of total plasma isoxicam after a single oral dose.