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Physiological sensors are commonly applied for user state monitoring and consequent machine behavior adaptation in applications such as rehabilitation and intelligent cars. While more accurate user state monitoring is known to lead to better user experience, increased accuracy often requires more sensors or more complex sensors. The increased setup time and discomfort involved in the use of such sensors may itself worsen user experience. To examine this effect, we conducted a study where 72 participants interacted with a computer-based multitasking scenario whose difficulty was periodically adapted - ostensibly based on data from either a remote eye tracker or a lab-grade “wet” electroencephalography sensor. Deception was used to ensure consistent difficulty adaptation accuracies, and user experience was measured with the Intrinsic Motivation Inventory, NASA Task Load Index, and an ad-hoc scale. We found few user experience differences between the eye tracker and electroencephalography sensor - while one interaction effect was noted, it was small, and there were no other differences. This result is at first surprising and seems to indicate that comfort and setup time are not major factors for laboratory-based user experience evaluations of such technologies. However, the result is likely due to a suboptimal study protocol where each participant interacted with only one sensor. In future work, we will use an alternate protocol to further explore the effects of user comfort and setup time on user experience.
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Substituent Effects on Temperature Dependence of Kinetic Isotope Effects in Hydride-Transfer Reactions of NADH/NAD + Analogues in Solution: Reaction Center Rigidity Is the Key
- Award ID(s):
- 1800194
- PAR ID:
- 10173149
- Date Published:
- Journal Name:
- Organic Letters
- ISSN:
- 1523-7060
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Metronidazole and nimorazole are antibiotics of a nitroimidazole group which also may be potentially utilized as hypoxia radiosensitizers for the treatment of cancerous tumors. Hyperpolarization of15N nuclei in these compounds using SABRE‐SHEATH (Signal Amplification By Reversible Exchange in SHield Enables Alignment Transfer to Heteronuclei) approach provides dramatic enhancement of detection sensitivity of these analytes using magnetic resonance spectroscopy and imaging. Methanol‐d4is conventionally employed as a solvent in SABRE hyperpolarization process. Herein, we investigate SABRE‐SHEATH hyperpolarization of isotopically labeled [15N3]metronidazole and [15N3]nimorazole in nondeuterated methanol and ethanol solvents. Optimization of such hyperpolarization parameters as polarization transfer magnetic field, temperature, parahydrogen flow rate and pressure allowed us to obtain an average15N polarization of up to 7.2–7.4 % for both substrates. The highest15N polarizations were observed in methanol‐d4for [15N3]metronidazole and in ethanol for [15N3]nimorazole. At a clinically relevant magnetic field of 1.4 T the15N nuclei of these substrates possess long characteristic hyperpolarization lifetimes (T1) of ca. 1 to ca. 7 min. This study represents a major step toward SABRE in more biocompatible solvents, such as ethanol, and also paves the way for future utilization of these hyperpolarized nitroimidazoles as molecular contrast agents for MRI visualization of tumors.more » « less
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acs.orglett.0c02049
