691 research outputs found

    Development of a Microsoft Excel tool for one-parameter Rasch model of continuous items: an application to a safety attitude survey

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    Abstract Background Many continuous item responses (CIRs) are encountered in healthcare settings, but no one uses item response theory’s (IRT) probabilistic modeling to present graphical presentations for interpreting CIR results. A computer module that is programmed to deal with CIRs is required. To present a computer module, validate it, and verify its usefulness in dealing with CIR data, and then to apply the model to real healthcare data in order to show how the CIR that can be applied to healthcare settings with an example regarding a safety attitude survey. Methods Using Microsoft Excel VBA (Visual Basic for Applications), we designed a computer module that minimizes the residuals and calculates model’s expected scores according to person responses across items. Rasch models based on a Wright map and on KIDMAP were demonstrated to interpret results of the safety attitude survey. Results The author-made CIR module yielded OUTFIT mean square (MNSQ) and person measures equivalent to those yielded by professional Rasch Winsteps software. The probabilistic modeling of the CIR module provides messages that are much more valuable to users and show the CIR advantage over classic test theory. Conclusions Because of advances in computer technology, healthcare users who are familiar to MS Excel can easily apply the study CIR module to deal with continuous variables to benefit comparisons of data with a logistic distribution and model fit statistics

    Replication Attack Detection in Mobile Wireless Sensor Network with LEACH-ME Routing Protocol

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    Because the Wireless Sensor Network (WSN) nodes are low-cost devices, attackers may capture some nodes in this network and then duplicate these nodes to eavesdrop the transmitted messages or even control the network gradually without difficulty. This is the so-called node replication attack. This type of attacks could cause the huge threat to information security of WSNs. Therefore, in this paper, we would like to suggest a detection approach which can offer good performance but with higher energy consumption. Hence, it can provide an alternative solution for some specific applications that need better precision but do not care energy or lifespan too much

    The Adoption of Wikipedia: A Community- and Information Quality-Based View

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    The Web 2.0 model has aroused vast attention as it alters the traditional role of Internet users as pure information receivers. Wikipedia, as one of the most successful case of the Web 2.0 model, creates an online encyclopedia through the collective efforts of volunteers. Shared freely by all Internet users, it forms an online community platform on which users can seek and share knowledge. This study investigates the factors that affect the adoption of Wikipedia. Based on the TAM of Davis (1989), perceived critical mass, community identification, and perceived information quality were incorporated into the research model to explain the intention and usage of Wikipedia. This research is a work-in-progress and a questionnaire survey will be executed, targeting at Internet users who had prior experiences with knowledge seeking on Wikipedia

    Photoproducts of indomethacin exhibit decreased hydroxyl radical scavenging and xanthine oxidase inhibition activities

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    AbstractIndomethacin (IN) is a widely used nonsteroidal anti-inflammatory drug. In this study, four photoproducts of IN (IN1–IN4) were produced and isolated from photoirradiated IN. This study investigated the abilities of IN and its photoproducts to scavenge hydroxyl radicals and inhibit xanthine oxidase (XO). The hydroxyl radical-scavenging activity was measured in vitro by electron spin resonance spectrometry using 5,5-dimethyl-1-pyrroline-N-oxide as a spin trapping agent. Enzyme activity was measured by continuous monitoring of uric acid formation, using xanthine as a substrate. The results showed that, among all the related products, IN has the strongest hydroxyl radical-scavenging (IC50 = 65 μM) and XO inhibitory (IC50 = 86 μM) effects. To further understand the stereochemistry of the reactions between these IN derivatives and XO, we performed computer-aided molecular modeling. IN was the most potent inhibitor with the most favorable interaction in the reactive site. Various photoproducts exhibited affinity toward XO as a result of the absence of hydrogen bonding with molybdopterin domain

    Image operator learning coupled with CNN classification and its application to staff line removal

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    Many image transformations can be modeled by image operators that are characterized by pixel-wise local functions defined on a finite support window. In image operator learning, these functions are estimated from training data using machine learning techniques. Input size is usually a critical issue when using learning algorithms, and it limits the size of practicable windows. We propose the use of convolutional neural networks (CNNs) to overcome this limitation. The problem of removing staff-lines in music score images is chosen to evaluate the effects of window and convolutional mask sizes on the learned image operator performance. Results show that the CNN based solution outperforms previous ones obtained using conventional learning algorithms or heuristic algorithms, indicating the potential of CNNs as base classifiers in image operator learning. The implementations will be made available on the TRIOSlib project site.Comment: To appear in ICDAR 201

    Molecular epidemiology and emergence of worldwide epidemic clones of Neisseria meningitidis in Taiwan

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    BACKGROUND: Meningococcal disease is infrequently found in Taiwan, a country with 23 million people. Between 1996 and 2002, 17 to 81 clinical cases of the disease were reported annually. Reported cases dramatically increased in 2001–2002. Our record shows that only serogroup B and W135 meningococci have been isolated from patients with meningococcal disease until 2000. However, serogroup A, C and Y meningococci were detected for the first time in 2001 and continued to cause disease through 2002. Most of serogroup Y meningococcus infections localized in Central Taiwan in 2001, indicating that a small-scale outbreak of meningococcal disease had occurred. The occurrence of a meningococcal disease outbreak and the emergence of new meningococcal strains are of public health concern. METHODS: Neisseria meningitidis isolates from patients with meningococcal disease from 1996 to 2002 were collected and characterized by serogrouping, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). The genetic relatedness and clonal relationship between the isolates were analyzed by using the PFGE patterns and the allelic profiles of the sequence types (STs). RESULTS: Serogroups A, B, C, W135, Y, and non-serogroupable Neisseria meningitidis were, respectively, responsible for 2%, 50%, 2%, 35%, 9%, and 2% of 158 culture-confirmed cases of meningococcal disease in 1996–2002. Among 100 N. meningitidis isolates available for PFGE and MLST analyses, 51 different PFGE patterns and 30 STs were identified with discriminatory indices of 0.95 and 0.87, respectively. Of the 30 STs, 21 were newly identified and of which 19 were found in serogroup B isolates. A total of 40 PFGE patterns were identified in 52 serogroup B isolates with the patterns distributed over several distinct clusters. In contrast, the isolates within each of the serogroups A, C, W135, and Y shared high levels of PFGE pattern similarity. Analysis of the allelic profile of the 30 STs suggested the serogroup B isolates be assigned into 5 clonally related groups/ clonal complexes and 7 unique clones. The ST-41/44 complex/Lineage 3, and the ST-3439 and ST-3200 groups represented 79% of the serogroup B meningococci. In contrast, isolates within serogroups A, serogroup W135 (and C), and serogroup Y, respectively, simply belonged to ST-7, ST-11, and ST-23 clones. CONCLUSION: Our data suggested that serogroup B isolates were derived from several distinct lineages, most of which could either be indigenous or were introduced into Taiwan a long time ago. The serogroup A, W135 (and C), and Y isolates, respectively, belonged to the ST-7, ST-11, and ST-23, and the represented clones that are currently the major circulating clones in the world and are introduced into Taiwan more recently. The emergence of serogroup A, C and Y strains contributed partly to the increase in cases of meningococcal disease in 2001–2002
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