574 research outputs found

    The effects of design and operating variables on the response of an axial flow fan to inlet flow distortions

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    The results of a study of total pressure and velocity circumferential distortions in an axial-flow fan are presented. Some of the fundamental experimental data needed to understand distorted flow phenomena as affected by design and operating variables are provided. The flow through an isolated rotor was examined at various operating conditions with six different distortions and three different blade stagger angles. Circumferential surveys were conducted upstream and downstream of the rotor using five-hole probes in the nonnulling mode. The total pressure and axial velocity distortion data were analyzed to determine the degree of distortion attenuation as a function of blade stagger angle, mean incidence angle, and reduced frequency. The results indicate that, for the rotors tested, the mean incidence or loading has very little effect on the distortion attenuation

    Redefining genomic privacy: trust and empowerment

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    Fulfilling the promise of the genetic revolution requires the analysis of large datasets containing information from thousands to millions of participants. However, sharing human genomic data requires protecting subjects from potential harm. Current models rely on de-identification techniques in which privacy versus data utility becomes a zero-sum game. Instead, we propose the use of trust-enabling techniques to create a solution in which researchers and participants both win. To do so we introduce three principles that facilitate trust in genetic research and outline one possible framework built upon those principles. Our hope is that such trust-centric frameworks provide a sustainable solution that reconciles genetic privacy with data sharing and facilitates genetic research

    Development of a photosynthesis model with an emphasis on ecological applications

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    Photosynthesis was measured in leaves of Phaseolus vulgaris and analyzed according to the set of equations outlined previously by Tenhunen et al. (1976).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47716/1/442_2004_Article_BF00582889.pd

    Educational Brochures Influence Beliefs and Knowledge Regarding Exercise during Pregnancy: A Pilot Study

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    International Journal of Exercise Science 12(3): 581-589, 2019. Women who are pregnant report receiving little or no advice about physical activity during pregnancy from their obstetric provider. The purpose of this study was to assess the effectiveness of an evidence-based educational brochure on both immediate and two-week retention of knowledge about exercise during pregnancy. Thirty-two women of childbearing age (age: 25.0 ± 4.0 years, body mass index: 29.5 ± 6.5 kg/m2, 93.7% Caucasian, 83.4% had at least some college) completed a survey before exposure to an evidence-based educational brochure regarding exercise during pregnancy. Post surveys were taken immediately after viewing the educational brochure and again 2-weeks later. After exposure to educational brochures, survey scores on both surveys were significantly higher immediately-post and two-weeks post compared to baseline survey scores (Survey 1 (assessing beliefs) – pre: 79.2 ± 8.9%, post: 92.6 ± 7.4%, 2-weeks post: 92.0 ± 6.5%, p \u3c 0.001; Survey 2 (assessing knowledge) – pre: 65.3 ± 16.4%, post: 81.3 ± 14.9%, 2-weeks post: 78.8 ± 12.4%, p \u3c 0.001). No significant differences detected between immediate post and 2-weeks post for either Survey 1 (p = 0.72) or Survey 2 (p = 0.52); suggesting the information was retained. An evidence-based educational brochure is effective for improving and retaining information 2-weeks later regarding exercise during pregnancy. However, replication studies in more diverse populations are needed to confirm the results of this pilot study. The long-term goal for this line of research is to urge health care providers to consider providing patients with educational information in order to improve knowledge and patient-provider communication on this topic

    Proteome-based plasma biomarkers for Alzheimer's disease

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    Alzheimer's disease is a common and devastating disease for which there is no readily available biomarker to aid diagnosis or to monitor disease progression. Biomarkers have been sought in CSF but no previous study has used two-dimensional gel electrophoresis coupled with mass spectrometry to seek biomarkers in peripheral tissue. We performed a case-control study of plasma using this proteomics approach to identify proteins that differ in the disease state relative to aged controls. For discovery-phase proteomics analysis, 50 people with Alzheimer's dementia were recruited through secondary services and 50 normal elderly controls through primary care. For validation purposes a total of 511 subjects with Alzheimer's disease and other neurodegenerative diseases and normal elderly controls were examined. Image analysis of the protein distribution of the gels alone identifies disease cases with 56% sensitivity and 80% specificity. Mass spectrometric analysis of the changes observed in two-dimensional electrophoresis identified a number of proteins previously implicated in the disease pathology, including complement factor H (CFH) precursor and α-2-macroglobulin (α- 2M). Using semi-quantitative immunoblotting, the elevation of CFH and α- 2M was shown to be specific for Alzheimer's disease and to correlate with disease severity although alternative assays would be necessary to improve sensitivity and specificity. These findings suggest that blood may be a rich source for biomarkers of Alzheimer's disease and that CFH, together with other proteins such as α- 2M may be a specific markers of this illness. © 2006 The Author(s).link_to_subscribed_fulltex

    Decoding visual information from high-density diffuse optical tomography neuroimaging data

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    BACKGROUND: Neural decoding could be useful in many ways, from serving as a neuroscience research tool to providing a means of augmented communication for patients with neurological conditions. However, applications of decoding are currently constrained by the limitations of traditional neuroimaging modalities. Electrocorticography requires invasive neurosurgery, magnetic resonance imaging (MRI) is too cumbersome for uses like daily communication, and alternatives like functional near-infrared spectroscopy (fNIRS) offer poor image quality. High-density diffuse optical tomography (HD-DOT) is an emerging modality that uses denser optode arrays than fNIRS to combine logistical advantages of optical neuroimaging with enhanced image quality. Despite the resulting promise of HD-DOT for facilitating field applications of neuroimaging, decoding of brain activity as measured by HD-DOT has yet to be evaluated. OBJECTIVE: To assess the feasibility and performance of decoding with HD-DOT in visual cortex. METHODS AND RESULTS: To establish the feasibility of decoding at the single-trial level with HD-DOT, a template matching strategy was used to decode visual stimulus position. A receiver operating characteristic (ROC) analysis was used to quantify the sensitivity, specificity, and reproducibility of binary visual decoding. Mean areas under the curve (AUCs) greater than 0.97 across 10 imaging sessions in a highly sampled participant were observed. ROC analyses of decoding across 5 participants established both reproducibility in multiple individuals and the feasibility of inter-individual decoding (mean AUCs \u3e 0.7), although decoding performance varied between individuals. Phase-encoded checkerboard stimuli were used to assess more complex, non-binary decoding with HD-DOT. Across 3 highly sampled participants, the phase of a 60° wide checkerboard wedge rotating 10° per second through 360° was decoded with a within-participant error of 25.8±24.7°. Decoding between participants was also feasible based on permutation-based significance testing. CONCLUSIONS: Visual stimulus information can be decoded accurately, reproducibly, and across a range of detail (for both binary and non-binary outcomes) at the single-trial level (without needing to block-average test data) using HD-DOT data. These results lay the foundation for future studies of more complex decoding with HD-DOT and applications in clinical populations
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