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This paper presents a novel surrogate-based cross-correlation (SBCC) framework to improve the correlation performance for practical particle image velocimetry (PIV). The basic idea is that an optimized surrogate filter/image, replacing one raw image, will produce a more accurate and robust correlation signal. Specifically, the surrogate image is encouraged to generate a perfect Gaussian-shaped correlation map to tracking particles (PIV image pair) while producing zero responses to image noise (context images). The problem is formulated with an objective function composed of surrogate loss and consistency loss. As a result, the closed-form solution provides a multivariate operator that could consider other negative context images. Compared with state-of-the-art baseline methods (background subtraction, robust phase correlation, etc.), our SBCC method exhibits significant performance improvement (accuracy and robustness) in the synthetic dataset and several challenging experimental PIV cases. Moreover, our implementation with all details (https://github.com/yongleex/SBCC) is also available for interested researchers. [ABSTRACT FROM AUTHOR]

Y6-based nonfullerene organic solar cells (OSCs) have achieved an outstanding power conversion efficiency (PCE) of over 19% due to the low energy loss and high exciton dissociation efficiency with a small energy offset. However, the exciton dissociation mechanism is still under debate. It is unclear why a small energy offset can lead to efficient exciton dissociation in nonfullerene systems, but causes significant charge recombination in fullerene ones. Most of the previous theoretical studies have focused on the static properties of donor–acceptor heterojunctions, while neglecting excited electron dynamics and nonadiabatic effects. Here, we applied nonadiabatic molecular dynamics simulations to study the charge transfer dynamics in both donor:Y6 and donor:C60 crystalline systems. We found that thermal effects do not significantly influence the exciton dissociation in the NT-4T-FF:Y6 system, which aligns with experimental observations. Based on our simulations, we identified a five-step charge transfer process in nonfullerene systems. While previous studies suggested electrostatic interfacial fields from non-fullerene small molecule acceptors, our research reveals that strong donor–acceptor interactions primarily affect the local exciton states rather than the ground state. Consequently, the polarized local excitons play a key role in reducing the Coulomb attraction between electrons and holes, thus facilitating exciton dissociation with a small energy offset. In contrast, this mechanism is not observed in fullerene OSC systems. Our findings provide a fundamental basis for the further development of novel OSC materials with the potential for achieving even higher PCE. [ABSTRACT FROM AUTHOR]

Introduction: Despite many benefits offered by Health Information Technology (HIT) systems, new technology brings new and unforeseen risks to healthcare quality and patient safety if they're not properly planned, designed, implemented, and managed. This study examined health information technology-related (HIT) incidents to identify patient details-related issues, their association with contributing factors, and outcomes. Methods: Sources of information comprised retrospectively collected incident reports (n = 95) using two sampling methods, i.e., purposive and snowball sampling. The incident reports were analyzed using both the inductive method (thematic analysis) and the deductive approach using an existing framework, i.e., the International Classification for Patient Safety. Results: The studies identified 90 incidents with 120 patient details-related issues--categorized as either information-related (48%) or documentation-related (52%) problems; around two-thirds of the 120 issues were characterized by human factors. Of the total sample, 87 contributing factors were identified, of which "medical device/system" (45%) and "documentation" (20%) were the most common contributing factors. Of 90 incidents, more than half (59%) comprised patient-related outcomes--patient inconvenience (47%) and patient harm (12%) and the remaining 41% (n = 37) included staff or organization-related outcomes. Discussion: More than half of the incidents resulted in patient-related outcomes, namely patient inconvenience and patient harm, including disease risks, severe health deterioration, injury, and even patient death. Incidents associated with patient details can cause deleterious effects; therefore, characterizing them should be a routine part of clinical practice to improve the constantly changing healthcare system. [ABSTRACT FROM AUTHOR]

The nanoconfinement of water can result in dramatic differences in its physical and chemical properties compared to bulk water. However, a detailed molecular-level understanding of these properties is still lacking. Vibrational spectroscopy, such as Raman and infrared, is a popular experimental tool for studying the structure and dynamics of water, and is often complemented by atomistic simulations to interpret experimental spectra, but there have been few theoretical spectroscopy studies of nanoconfined water using first-principles methods at ambient conditions, let alone under extreme pressure–temperature conditions. Here, we compute the Raman and IR spectra of water nanoconfined by graphene at ambient and extreme pressure–temperature conditions using ab initio simulations. Our results revealed alterations in the Raman stretching and low-frequency bands due to the graphene confinement. We also found spectroscopic evidence indicating that nanoconfinement considerably changes the tetrahedral hydrogen bond network, which is typically found in bulk water. Furthermore, we observed an unusual bending band in the Raman spectrum at ∼10 GPa and 1000 K, which is attributed to the unique molecular structure of confined ionic water. Additionally, we found that at ∼20 GPa and 1000 K, confined water transformed into a superionic fluid, making it challenging to identify the IR stretching band. Finally, we computed the ionic conductivity of confined water in the ionic and superionic phases. Our results highlight the efficacy of Raman and IR spectroscopy in studying the structure and dynamics of nanoconfined water in a large pressure–temperature range. Our predicted Raman and IR spectra can serve as a valuable guide for future experiments. [ABSTRACT FROM AUTHOR]