Expansion and Evaluation of a Step-Based Tutorial Program for Linear Circuit AnalysisComputer-aided instructional methods offer the possibility to allow students to work individuallyat their own ...pace, receiving feedback customized to their needs. Step-based tutorial systems, inwhich each step of a student’s work is input and immediately evaluated, are known to besignificantly more effective than traditional answer-based systems that only check thecorrectness of a final answer. Previously, we described the initial development of such a systemfor linear circuit analysis, in which automated algorithms are used to generate an unlimitedsupply of topologically different circuits of selected complexity as well as fully worked, error-free solutions to those exercises. The system accepts and evaluates student input in the form ofequations (entered using a template-based system to guide students), re-drawn circuit diagrams(using a drawing interface), simplified systems of equations, matrix equations, numericalanswers, and waveform sketches (entered using a specially designed drawing interface). Specialpedagogical features such as color coding are included to highlight concepts to students. Atutorial authoring system allows instructors to specify the ways in which sequences of problems,exercises, and expository material are presented to the student. Web-based exercises are used toprovide specific practice on unit conversions and complex number manipulation, two essentialskills in this course. Here, we describe the expansion of this system to cover a broader range oftopics in typical introductory circuit analysis courses. We further discuss the testing of thesystem both in a laboratory-based setting and in live classes, involving over 15 large sections ofa linear circuits class at our institution over several semesters and initial results in classes at threepartner institutions involving a diverse range of student characteristics. All student activity inthe system is logged to a central server, where it is available for later download and analysis.Instructors and administrators have a web-based portal where they can monitor student progress.The laboratory experiments involved a controlled, randomized trial in which we compared theeffectiveness of our system using a pre- and post-test for both a qualitative and quantitative topicto the traditional method of textbook-based problem solving. Students assigned to solveconventional problems increased their test scores by an average of 2.9/100 points, from 58.6 to61.6%, whereas the software users increased by 28.6 points, from 57.8 to 86.4%, a roughly 10Ximprovement. The statistically significant effect size (Cohen d-value) was 1.21 pooled standarddeviations, a very large effect. The Instructional Materials Motivation Survey of Keller wasadministered to both groups, showing a significant 0.53 point higher average for the softwareusers. In classroom use, about 99% of students rated the tutorials as either “very useful” or“somewhat useful” for learning the material, with over 74% considering them “very useful.”Student comments were generally very favorable, with students praising their ability to receiveunlimited practice with no penalty for wrong answers. They appreciated the confidence-buildingaspects of the software as well as the efficiency with which the rapid feedback helped them learnthe material.Fig. 1. Display of successfully entered simplified node equations and corresponding matrixequation. Highlighting of a selected KCL equation and labeling of the currents leaving aselected supernode with arrows that are color-coded to match the color of each term in theequation is also illustrated.Fig. 2. Screen shot of the prototype web-based equation sketching interface, showing apiecewise function that is being entered (and displayed below it).
While a growing number of serious games have been developed around science and engineering concepts, few are designed with an understanding of the socio-emotional aspects of gameplay. Positive affect ...has been shown to increase learning performance and retention. In this paper, we address enjoyment generated during the design of a bioinformatics computer game. We provide insights from a co-design process with high school students, and discuss the results of an initial user study in a biology classroom. We identify three areas of design focus for emotionally compelling science games that offer ways to integrate diverse player experiences: serendipitous experiences, emotion-laden ethics, and skill transfer. Our framework has design implications for creating science-based learning games, as well as more broadly in the design and implementation of other collaborative science learning environments.
DNA methylation (DNAme) is a critical component of the epigenetic regulatory machinery and aberrations in DNAme patterns occur in many diseases, such as cancer. Mapping and understanding DNAme ...profiles offers considerable promise for reversing the aberrant states. There are several approaches to analyze DNAme, which vary widely in cost, resolution and coverage. Affinity capture and high-throughput sequencing of methylated DNA strike a good balance between the high cost of whole genome bisulphite sequencing (WGBS) and the low coverage of methylation arrays. However, existing methods cannot adequately differentiate between hypomethylation patterns and low capture efficiency, and do not offer flexibility to integrate copy number variation (CNV). Furthermore, no uncertainty estimates are provided, which may prove useful for combining data from multiple protocols or propagating into downstream analysis. We propose an empirical Bayes framework that uses a fully methylated (i.e. SssI treated) control sample to transform observed read densities into regional methylation estimates. In our model, inefficient capture can be distinguished from low methylation levels by means of larger posterior variances. Furthermore, we can integrate CNV by introducing a multiplicative offset into our Poisson model framework. Notably, our model offers analytic expressions for the mean and variance of the methylation level and thus is fast to compute. Our algorithm outperforms existing approaches in terms of bias, mean-squared error and coverage probabilities as illustrated on multiple reference datasets. Although our method provides advantages even without the SssI-control, considerable improvement is achieved by its incorporation. Our method can be applied to methylated DNA affinity enrichment assays (e.g MBD-seq, MeDIP-seq) and a software implementation is available in the Bioconductor Repitools package.
National Institutes of Health consensus and state-of-the-science statements are prepared by independent panels of health professionals and public representatives on the basis of (1) the results of a ...systematic literature review prepared under contract with the Agency for Healthcare Research and Quality (AHRQ), (2) presentations by investigators working in areas relevant to the conference questions during a 2-day public session, (3) questions and statements from conference attendees during open discussion periods that are part of the public session, and (4) closed deliberations by the panel during the remainder of the second day and morning of the third. This statement is an independent report of the panel and is not a policy statement of the NIH or the U.S. Government.The statement reflects the panel's assessment of medical knowledge available at the time the statement was written. Thus, it provides a "snapshot in time" of the state of knowledge on the conference topic. When reading the statement, keep in mind that new knowledge is inevitably accumulating through medical research.
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