3,177 research outputs found

    Parameter selection for segregating speech from background noise

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    Business/Education/Speech and Hearing Science: 1st Place (The Ohio State University Denman Undergraduate Research Forum)Understanding speech in background noise remains a primary challenge faced by hearing-impaired listeners. Ideal binary masking (IBM) is an effective technique to facilitate understanding of a target signal in noisy backgrounds, and IBM estimation is the goal of an effective speech-from-noise separation algorithm that holds promise for alleviating limitations of hearing impairment. In IBM processing, a speech-and-noise mixture is divided into a grid of time-frequency (T-F) units, which are discarded if their degree of noise corruption (reflected as a signal-to-noise ratio, or SNR) exceeds a certain local criterion (LC). Prior work determined that the relationship between the overall SNR of the original speech-noise mixture and LC (the relative criterion or RC) was important for determining intelligibility. This work also suggests that there is a wide range of RC values over which performance scores reach maximum. The current study investigates whether these scores reflect a performance ceiling rather than a true maximum. Consonant recognition was tested in normal-hearing listeners using seven different RC values. The background noise was speech-shaped noise. An RC performance function was obtained that did not display the ceiling effect limitations of previous work, suggesting that the optimal RC value may be different from previous estimates. These findings have implications for selections of LC in IBM estimations. They also suggest appropriate parameters for testing the effect of varying LC within a single mask according to specific frequency contributions to overall speech intelligibility. Such developments may contribute to reducing the struggles that hearing-impaired listeners face in noise.Buckeye Language Network Study of Language Variation (SoLV) Undergraduate Research AwardCollege of Arts and Sciences Undergraduate Research ScholarshipAcademic Major: Speech and Hearing Scienc

    Gravity Fed Water System

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    The Gravity Fed Water Project aims to provide direct access to safe and clean water to about 150 people in Sipacapa, Guatemala by using gravity to transport water from groundwater seeps down a mountain to the community. The project partners with the Mennonite Central Committee. Concrete intake structures will be built for various groundwater seeps, then water from those will be combined into one large concrete intake structure. The water will then be piped down to a concrete water tank which will help to store enough water for a day\u27s use for the village. There will then be piping going to two different locations which will each have a storage tank. The Gravity Fed Water team plans to travel to the site to install part of the system in the future, although the date is uncertain. While in Guatemala, onsite water testing will be done for bacterial coliforms and the intake structure and the piping to the first storage tank will be built.https://mosaic.messiah.edu/engr2020/1010/thumbnail.jp

    A Comparison of 4-H and Other Youth Development Organizations in the Development of Life Skills

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    The article briefly describes the results of a study on the influence of 4-H and other youth development programs on the development of 36 life skills including critical thinking, goal setting, communication, decision-making and community service. Respondents (n=223) were high achieving 4-H alumni who participated it the Oklahoma 4-H Program between the years 1969 and 1998. Results suggest that while respondents credited 4-H with influencing the development of the majority of the identified life skills, other youth organizations were also identified as having some influence on the development in different life skills. Recommendations for 4-H programming are offered

    Enantioselective Total Synthesis of (+)-Psiguadial B

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    The first enantioselective total synthesis of the cytotoxic natural product (+)-psiguadial B is reported. Key features of the synthesis include (1) the enantioselective preparation of a key cyclobutane intermediate by a tandem Wolff rearrangement/asymmetric ketene addition, (2) a directed C(sp^3)–H alkenylation reaction to strategically forge the C1–C2 bond, and (3) a ring-closing metathesis to build the bridging bicyclo[4.3.1]decane terpene framework

    Brief mindfulness training enhances cognitive control in socioemotional contexts: Behavioral and neural evidence.

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    In social contexts, the dynamic nature of others' emotions places unique demands on attention and emotion regulation. Mindfulness, characterized by heightened and receptive moment-to-moment attending, may be well-suited to meet these demands. In particular, mindfulness may support more effective cognitive control in social situations via efficient deployment of top-down attention. To test this, a randomized controlled study examined effects of mindfulness training (MT) on behavioral and neural (event-related potentials [ERPs]) responses during an emotional go/no-go task that tested cognitive control in the context of emotional facial expressions that tend to elicit approach or avoidance behavior. Participants (N = 66) were randomly assigned to four brief (20 min) MT sessions or to structurally equivalent book learning control sessions. Relative to the control group, MT led to improved discrimination of facial expressions, as indexed by d-prime, as well as more efficient cognitive control, as indexed by response time and accuracy, and particularly for those evidencing poorer discrimination and cognitive control at baseline. MT also produced better conflict monitoring of behavioral goal-prepotent response tendencies, as indexed by larger No-Go N200 ERP amplitudes, and particularly so for those with smaller No-Go amplitude at baseline. Overall, findings are consistent with MT's potential to enhance deployment of early top-down attention to better meet the unique cognitive and emotional demands of socioemotional contexts, particularly for those with greater opportunity for change. Findings also suggest that early top-down attention deployment could be a cognitive mechanism correspondent to the present-oriented attention commonly used to explain regulatory benefits of mindfulness more broadly

    A modular approach to prepare enantioenriched cyclobutanes: synthesis of (+)-rumphellaone A

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    A modular synthesis of enantioenriched polyfunctionalized cyclobutanes was developed that features an 8-aminoquinolinamide directed C–H arylation reaction. The C–H arylation products were derivatized through subsequent decarboxylative coupling processes. This synthetic strategy enabled a 9-step enantioselective total synthesis of the antiproliferative meroterpenoid (+)-rumphellaone A

    Are some teat disinfectant formulations more effective against specific bacteria isolated on teat skin than others?

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    peer-reviewedThe use of pre- and post-milking teat disinfectants can reduce teat bacterial load and aid in the collection of high-quality milk. The objective of this study was to compare the reduction in bacteria populations on teat skin after the application of different commercial teat disinfectant products. Ten teat disinfectant products were applied to the teats of 10 Holstein–Friesian cows. One cow received one teat disinfectant product at each sampling point before cluster application for milking. A composite swab sample was taken of the 4 teats of each cow before and after teat disinfectant application. Swab samples were placed on three different selective agars to enumerate bacterial counts of staphylococcal, streptococcal and coliforms isolates on teat skin. Staphylococcal isolates were the most prominent bacterial group recovered on teat swabs (49%), followed by streptococcal (36%) and coliform (15%) isolates before the application of disinfectant. The average bacterial reductions on teat skin were shown to be 76%, 73% and 60% for staphylococcal, streptococcal and coliform isolates, respectively. All of the teat disinfectant products tested reduced teat bacterial load for all three bacterial groups. Product 4 containing 0.6% w/w diamine was the most effective against bacterial populations of staphylococcal and streptococcal isolates on teat skin with a reduction of 90% and 94%, respectively. Whereas product 10, which contained 0.5% w/w iodine, resulted in the highest reduction in coliforms on teat skin with a reduction of 91%. Results from this study suggest that specific bacterial population loads on teats can be reduced using different teat disinfectant formulations

    Outdoor PV Degradation Comparison

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    As photovoltaic (PV) penetration of the power grid increases, it becomes vital to know how decreased power output may affect cost over time. In order to predict power delivery, the decline or degradation rates must be determined accurately. At the Performance and Energy Rating Testbed (PERT) at the Outdoor Test Facility (OTF) at the National Renewable Energy Laboratory (NREL) more than 40 modules from more than 10 different manufacturers were compared for their long-term outdoor stability. Because it can accommodate a large variety of modules in a limited footprint the PERT system is ideally suited to compare modules side-by-side under the same conditions
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