4,369 research outputs found

    Key Experimental Approaches in DNA Nanotechnology

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    DNA nanotechnology combines unusual DNA motifs with sticky‐ended cohesion to build polyhedral objects, topological targets, nanomechanical devices, and both crystalline and aperiodic arrays. The goal of DNA nanotechnology is control of the structure of macroscopic matter on the finest possible scale. Applications are expected to arise in the areas of X‐ray crystallography, nanoelectronics, nanorobotics, and DNA‐based computation. DNA and its close molecular relatives appear extremely well suited for these goals. This overview covers the generation of new DNA motifs, construction methods (synthesis, hybridization, phosphorylation, ligation), and a variety of methods for characterization of motifs, devices, and arrays. Finally, the use of DNA nanotechnology as a tool in biochemistry is discussed.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143741/1/cpnc1201.pd

    Psychosocial Predictors of Metabolic Syndrome among Latino Groups in the Multi-Ethnic Study of Atherosclerosis (MESA).

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    ObjectiveWe sought to determine the contribution of psychological variables to risk for metabolic syndrome (MetS) among Latinos enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA), and to investigate whether social support moderates these associations, and whether inflammatory markers mediate the association between psychological variables and MetS.Research design and methodsCross-sectional analyses at study baseline were conducted with a national Latino cohort (n = 1,388) that included Mexican Americans, Dominican Americans, Puerto Rican Americans and Central/South Americans. Hierarchical logistic regression analyses were conducted to test the effects of psychosocial variables (chronic stress, depressive symptoms, and social support) on MetS. In addition, separate subgroup-specific models, controlling for nationality, age, gender, socioeconomic position, language spoken at home, exercise, smoking and drinking status, and testing for the effects of chronic stress, depressive symptoms and inflammation (IL-6, CRP, fibrinogen) in predicting risk for MetS were conducted.ResultsIn the overall sample, high chronic stress independently predicted risk for MetS, however this association was found to be significant only in Mexican Americans and Puerto Rican Americans. Social support did not moderate the associations between chronic stress and MetS for any group. Chronic stress was not associated with inflammatory markers in either the overall sample or in each group.ConclusionsOur results suggest a differential contribution of chronic stress to the prevalence of MetS by national groups

    Listening Effort Outcome Measures in Adult Populations

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    Listening effort is being considered clinically as an important indicator of patient success with amplification. Listening effort refers to “the mental exertion required to attend to, and understand, an auditory message”. (McGarrigle et al., 2014) Cognitive ability, age, and degree of hearing impairment all must considered when measuring the effort one is exerting on a specific task. Listening effort can be measured using subjective tools, electrophysiologic measures, or with a dual-task paradigm. Subjective tools include self-reports and questionnaires. Electrophysiologic measures can consist of measuring pupil dilation, heart rate variability, and skin conductance. A dual-task paradigm is set-up with two tasks performed by a person simultaneously. The amount of decline on the secondary task compared to when that task is completed in isolation, indicates the amount of effort that was exerted on the task. Each method has its strengths as well as its limitations. This paper discusses the current research on the various methods to measuring listening effort and provides clinical applications for these outcome measures

    Value of Otoacoustic Emissions Testing in Pre-school Hearing Screenings: A Literature Review

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    Unidentified hearing loss in children can have a potential effect on their speech and language, educational, cognitive, and social development. The goal of early detection is to minimize the effects of hearing loss through the appropriate referral for diagnosis and treatment. Hearing screenings throughout the preschool and school-age years are vital for the detection of a late-onset, late identified, or acquired hearing loss. Three influential organizations known as The American Academy of Audiology (AAA), The American Speech- Language-Hearing Association (ASHA), and The National Center for Hearing Assessment and Management (NCHAM), have considered behavioral pure tone screening as the “gold standard”for hearing screening protocol across a range of age groups. Although ideally this gold standard would be implemented in all cases, there may be some instances in which the recommended protocol is not appropriate. Performing a pure tone hearing screening may not be plausible for large groups of children, or those who are not capable of conditioning to the task. In these cases, the use of Otoacoustic Emissions (OAEs) has been suggested as an alternative. The aim of this literature review is to discuss the purpose of preschool and school-age hearing screenings, which screening tools are effective in identifying hearing loss in children, and what the appropriate protocol should be for those screening tools. If OAEs were to be substituted for pure tone screenings, the selection of the pass/fail criteria and specific protocol should maximize the number of children being correctly identified with a hearing loss
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