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  1. Abstract

    The research presented in this paper investigated the changes that occur in the prefrontal cortex (PFC) when new ideas are introduced during engineering design. Undergraduate and graduate engineering students (n = 25) were outfitted with a functional near-infrared spectroscopy (fNIRS) headband. Students were asked to design a personal entertainment system while thinking aloud. New ideas were timestamped with the fNIRS data across 48 channels grouped into eight regions within the PFC. The data were preprocessed using temporal derivative distribution repair motion correction, finite impulse response bandpass filter, and the modified beer-lambert law to convert optical density into hemoglobin concentration. Baseline neurocognitive activation and physiological noise were removed. The study found a significant decrease in oxygenated hemoglobin in the left dorsolateral prefrontal cortex and a subregion of the left ventrolateral prefrontal cortex when new ideas were introduced during design. This finding begins to provide a neurocognitive signature of what a new idea looks like as it arises in the brain. This could be used to develop tools and techniques to inhibit this brain region or use this insight to predict when designers will experience a new idea based on their neural activation.

     
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  2. Smirnoff, Nick (Ed.)
    Abstract A 35 kDa monomeric purple acid phosphatase (APase) was purified from cell wall extracts of Pi starved (–Pi) Arabidopsis thaliana suspension cells and identified as AtPAP17 (At3g17790) by mass spectrometry and N-terminal microsequencing. AtPAP17 was de novo synthesized and dual-localized to the secretome and/or intracellular fraction of –Pi or salt-stressed plants, or senescing leaves. Transiently expressed AtPAP17–green fluorescent protein localized to lytic vacuoles of the Arabidopsis suspension cells. No significant biochemical or phenotypical changes associated with AtPAP17 loss of function were observed in an atpap17 mutant during Pi deprivation, leaf senescence, or salinity stress. Nevertheless, AtPAP17 is hypothesized to contribute to Pi metabolism owing to its marked up-regulation during Pi starvation and leaf senescence, broad APase substrate selectivity and pH activity profile, and rapid repression and turnover following Pi resupply to –Pi plants. While AtPAP17 also catalyzed the peroxidation of luminol, which was optimal at pH 9.2, it exhibited a low Vmax and affinity for hydrogen peroxide relative to horseradish peroxidase. These results, coupled with absence of a phenotype in the salt-stressed or –Pi atpap17 mutant, do not support proposals that the peroxidase activity of AtPAP17 contributes to the detoxification of reactive oxygen species during stresses that trigger AtPAP17 up-regulation. 
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  3. The Carnegie Supernova Project-II (CSP-II) was an NSF-funded, four-year program to obtain optical and near-infrared observations of a “Cosmology” sample of ˜100 Type Ia supernovae located in the smooth Hubble flow (0.03 ≲ z ≲ 0.10). Light curves were also obtained of a “Physics” sample composed of 90 nearby Type Ia supernovae at z ≤ 0.04 selected for near-infrared spectroscopic timeseries observations. The primary emphasis of the CSP-II is to use the combination of optical and near-infrared photometry to achieve a distance precision of better than 5%. In this paper, details of the supernova sample, the observational strategy, and the characteristics of the photometric data are provided. In a companion paper, the near-infrared spectroscopy component of the project is presented. 
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