222 research outputs found

    Retrieving Ambiguous Sounds Using Perceptual Timbral Attributes in Audio Production Environments

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    For over an decade, one of the well identified problem within audio production environments is the effective retrieval and management of sound libraries. Most of the self-recorded and commercially produced sound libraries are usually well structured in terms of meta-data and textual descriptions and thus allowing traditional text-based retrieval approaches to obtain satisfiable results. However, traditional information retrieval techniques pose limitations in retrieving ambiguous sound collections (ie. sounds with no identifiable origin, foley sounds, synthesized sound effects, abstract sounds) due to the difficulties in textual descriptions and the complex psychoacoustic nature of the sound. Early psychoacoustical studies propose perceptual acoustical qualities as an effective way of describing these category of sounds [1]. In Music Information Retrieval (MIR) studies, this problem were mostly studied and explored in context of content-based audio retrieval. However, we observed that most of the commercial available systems in the market neither integrated advanced content-based sound descriptions nor the visualization and interface design approaches evolved in the last years. Our research was mainly aimed to investigate two things; 1. Development of audio retrieval system incorporating high level timbral features as search parameters. 2. Investigate user-centered approach in integrating these features into audio production pipelines using expert-user studies. In this project, We present an prototype which is similar to traditional sound browsers (list-based browsing) with an added functionality of filtering and ranking sounds by perceptual timbral features such as brightness, depth, roughness and hardness. Our main focus was on the retrieval process by timbral features. Inspiring from the recent focus on user-centered systems ([2], [3]) in the MIR community, in-depth interviews and qualitative evaluation of the system were conducted with expert-user in order to identify the underlying problems. Our studies observed the potential applications of high-level perceptual timbral features in audio production pipelines using a probe system and expert-user studies. We also outlined future guidelines and possible improvements to the system from the outcomes of this research

    'I want to go back to the text': Response Strategies on the Reading Subtest of the New TOEFL

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    This post-peer-review, pre-copyedit version of the article submitted to IUPUI ScholarWorks as part of the OASIS Project. Article reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Permission granted through posted policies on copyright owner’s website or through direct contact with copyright owner.This study describes the reading and test-taking strategies that test takers used on the ‘Reading’ section of the LanguEdge Courseware (2002) materials developed to familiarize prospective respondents with the new TOEFL. The investigation focused on strategies used to respond to more traditional ‘single selection’ multiple-choice formats (i.e., Basic Comprehension and Inferencing questions) and the new selected-response (multiple selection, drag-and-drop) Reading to Learn items. The latter were designed to simulate the academic skill of forming a comprehensive and coherent representation of an entire text, rather than focusing on discrete points in the text. Verbal report data were collected from 32 students, representing four language groups (Chinese, Japanese, Korean, and ‘Other’) doing the Reading section tasks from the LanguEdge Courseware materials. Students were randomly assigned to two of the six reading subtests, each consisting of a 600–700 word text with 12–13 items, and subjects’ verbal reports accompanying items representing each of the ten item types were evaluated to determine strategy use. The findings provide insights into the response behaviors prompted by the reading tasks on the new TOEFL

    Distance dependence of photoinduced long-range electron transfer in zinc/ruthenium-modified myoglobins

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    An experimental investigation of the distance dependence of long-range electron transfer in zinc/ruthenium-modified myoglobins has been performed. The modified proteins were prepared by substitution of zinc mesoporphyrin IX diacid (ZnP) for the heme in each of four previously characterized pentaammineruthenium(III) (a_5Ru;a = NH_3) derivatives of sperm whale myoglobin (Mb): a_5Ru(His-48)Mb, a_5Ru(His-12)Mb, a_5Ru(His-116)Mb, a_5Ru(His-81)Mb. Electron transfer from the ZnP triplet excited state (^3ZnP*) to Ru^3+, ^3ZnP*-Ru^3+ → ZnP^+-Ru^2+ (ΔE° ~ 0.8V) was measured by time-resolved transient absorption spectroscopy: rate constants (k_f) are 7.0 × 10^4 (His-48), 1.0 × 10^2 (His-12), 8.9 × 10^1 (His-116), and 8.5 × 10^1 (His-81) s^-1 at 25 °C. Activation enthalpies calculated from the temperature dependences of the electron-transfer rates over the range 5-40 °C are 1.7 ± 1.6 (His-48), 4.7 ± 0.9 (His-12), 5.4 ± 0.4 (His-116), and 5.6 ± 2.5 (His-81) kcal mol^-1. Electron-transfer distances (d = closest ZnP edge to a_5Ru(His) edge; angstroms) were calculated to fall in the following ranges: His-48, 11.8-16.6; His-12, 21.5-22.3; His-116, 19.8-20.4; His-81, 18.8-19.3. The rate-distance equation is k_f = 7.8 × 10^8 exp[-0.9l(d - 3)] s^-1 . The data indicate that the ^3ZnP*-Ru(His-12)^3+ electronic coupling may be enhanced by an intervening tryptophan (Trp-14)

    Color discrimination errors associate with axial motor impairments in Parkinson’s Disease

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    BackgroundVisual function deficits are more common in imbalance‐predominant compared to tremor‐predominant PD, suggesting a pathophysiological role of impaired visual functions in axial motor impairments.ObjectiveTo investigate the relationship between changes in color discrimination and motor impairments in PD while accounting for cognitive or other confounder factors.MethodsPD subjects (n = 49, age 66.7 ± 8.3 years; Hoehn & Yahr stage 2.6 ± 0.6) completed color discrimination assessment using the Farnsworth‐Munsell 100 Hue Color Vision Test, neuropsychological, motor assessments, and [11C]dihydrotetrabenazine vesicular monoamine transporter type 2 PET imaging. MDS‐UPDRS sub‐scores for cardinal motor features were computed. Timed Up & Go mobility and walking tests were assessed in 48 subjects.ResultsBivariate correlation coefficients between color discrimination and motor variables were significant only for the Timed Up & Go test (RS = 0.44, P = 0.0018) and the MDS‐UPDRS axial motor scores (RS = 0.38, P = 0.0068). Multiple regression confounder analysis using the Timed Up & Go as outcome parameter showed a significant total model (F(5,43) = 7.3, P < 0.0001) with significant regressor effects for color discrimination (standardized ÎČ = 0.32, t = 2.6, P = 0.012), global cognitive Z‐score (ÎČ = −0.33, t = −2.5, P = 0.018), duration of disease (ÎČ = 0.26, t = 1.8, P = 0.038), but not for age or striatal dopaminergic binding. The color discrimination test was also a significant independent regressor in the MDS‐UPDRS axial motor model (standardized ÎČ = 0.29, t = 2.4, P = 0.022; total model t(5,43) = 6.4, P = 0.0002).ConclusionsColor discrimination errors associate with axial motor features in PD independent of cognitive deficits, nigrostriatal dopaminergic denervation, and other confounder variables. These findings may reflect shared pathophysiology between color discrimination visual impairments and axial motor burden in PD.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141397/1/mdc312527.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/141397/2/mdc312527_am.pd

    Apparent Thixotropic Properties of Saline/Glycerol Drops with Biotinylated Antibodies on Streptavidin-Coated Glass Slides: Implications for Bacterial Capture on Antibody Microarrays

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    The thixotropic-like properties of saline/glycerol drops, containing biotinylated capture antibodies, on streptavidin-coated glass slides have been investigated, along with their implications for bacterial detection in a fluorescent microarray immunoassay. The thixotropic-like nature of 60:40 saline-glycerol semisolid droplets (with differing amounts of antibodies) was observed when bacteria were captured, and their presence detected using a fluorescently-labeled antibody. Semisolid, gel-like drops of biotinylated capture antibody became liquefied and moved, and then returned to semisolid state, during the normal immunoassay procedures for bacterial capture and detection. Streaking patterns were observed that indicated thixotropic-like characteristics, and this appeared to have allowed excess biotinylated capture antibody to participate in bacterial capture and detection. When developing a microarray for bacterial detection, this must be considered for optimization. For example, with the appropriate concentration of antibody (in this study, 0.125 ng/nL), spots with increased diameter at the point of contact printing (and almost no streaking) were produced, resulting in a maximal signal. With capture antibody concentrations greater than 0.125 ng/nL, the excess biotinylated capture antibody (i.e., that which was residing in the three-dimensional, semisolid droplet space above the surface) was utilized to capture more bacteria. Similarly, when the immunoassay was performed within a hydrophobic barrier (i.e., without a coverslip), brighter spots with increased signal were observed. In addition, when higher concentrations of cells (∌108 cells/mL) were available for capture, the importance of unbound capture antibody in the semisolid droplets became apparent because washing off the excess, unbound biotinylated capture antibody before the immunoassay was performed reduced the signal intensity by nearly 50%. This reduction in signal was not observed with lower concentrations of cells (∌106 cells/mL). With increased volumes of capture antibody, abnormal spots were visualized, along with decreased signal intensity, after bacterial detection, indicating that the increased droplet volume detrimentally affected the immunoassay

    Parkinson's disease biomarkers: perspective from the NINDS Parkinson's Disease Biomarkers Program

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    Biomarkers for Parkinson's disease (PD) diagnosis, prognostication and clinical trial cohort selection are an urgent need. While many promising markers have been discovered through the National Institute of Neurological Disorders and Stroke Parkinson's Disease Biomarker Program (PDBP) and other mechanisms, no single PD marker or set of markers are ready for clinical use. Here we discuss the current state of biomarker discovery for platforms relevant to PDBP. We discuss the role of the PDBP in PD biomarker identification and present guidelines to facilitate their development. These guidelines include: harmonizing procedures for biofluid acquisition and clinical assessments, replication of the most promising biomarkers, support and encouragement of publications that report negative findings, longitudinal follow-up of current cohorts including the PDBP, testing of wearable technologies to capture readouts between study visits and development of recently diagnosed (de novo) cohorts to foster identification of the earliest markers of disease onset
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