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Mixed Quantum/Classical Theory Approach to Rotationally Inelastic Molecular Collisions Implemented on a Quantum Computer
No full textAll elements of a quantum algorithm for calculations of rotationally inelastic molecule + atom scattering within the framework of a mixed quantum/classical theory are outlined. In this approach, the rotational motion of the molecule is described quantum mechanically using the time-dependent Schrödinger equation, while the scattering process of two collision partners is treated classically. The matrix of potential coupling is precomputed on a classical processor, whereas the quantum hardware is used to propagate the system of coupled equations for the rotational state-to-state transitions. All quantum circuits needed for practical implementation of the algorithm are presented. First, the quantum codes written in Qiskit are rigorously tested by running calculations for a N2 + O collision on a classical emulator of quantum hardware using a realistic potential energy surface of this system and comparing these results against the results obtained by the MQCT code. Next, these codes are run on the actual quantum hardware, such as the publicly available IBM Brisbane, Kyiv, and Sherbrooke. A very good agreement with benchmark data was obtained. To the best of our knowledge, this is the first proof-of-principle calculation of inelastic scattering implemented successfully on a quantum computer using a case study within mixed quantum/classical framework
Experiences of Discrimination During Pregnancy Predict Altered Neonatal Hair Cortisol at Birth
No full textObjective Prenatal glucocorticoids (e.g., cortisol) are a widely proposed prenatal programming mechanism, yet few studies directly measure fetal cortisol. Neonatal hair provides a non-invasive method to assess fetal cortisol. The current studies test the association between maternal exposure to discrimination and fetal cortisol, as measured in neonatal hair, in two cohorts. Methods Study 1: Pregnant individuals (N = 65) and their neonates (61.8 % female) participated in study 1 between 2017 and 2021. Participants self-identified as Asian (6.2 %), Black (21.5 %), Latinx (35.4 %), Multiracial or Multiethnic (35.4 %), and Native Hawaiian or Pacific Islander (1.5 %). Experiences of discrimination were measured using the Everyday Discrimination Scale. Neonatal hair samples were collected close to birth (Mediandays=1.30, IQRdays=0.96–2.03). Results Study 1: Higher experiences of everyday discrimination among pregnant individuals were associated with lower hair cortisol levels in neonates (r = -.28, p = .031). Methods Study 2: Pregnant individuals of Mexican descent (N = 73) and their neonates (50.7 % female) participated in study 2 between 2017 and 2020. Participants reported on their exposure to experiences of discrimination using the Discrimination Stress Scale, and neonatal hair samples were collected shortly after birth (Mediandays=13.0, IQRdays=11–18). Results Study 2: Those who had higher discrimination stress during pregnancy had neonates with higher cortisol than those with low discrimination (F(1,70)= 3.78, p = .03), but this relation did not remain significant after controlling for gestational age. Conclusion Across two cohorts, higher experiences of discrimination were associated with alterations in neonatal hair cortisol. Both higher and lower neonatal hair cortisol are linked to poorer neonatal development, indicating that experiences of discrimination might be a potential source of health disparities in the next generation
Gamified mHealth System for Evaluating Upper Limb Motor Performance in Children: Cross-Sectional Feasibility Study
No full textBackground: Approximately 17% of children in the United States have been diagnosed with a developmental or neurological disorder that affects upper limb (UL) movements needed for completing activities of daily living. Gold-standard laboratory assessments of the UL are objective and precise but may not be portable, while clinical assessments can be time-intensive. We developed MoEvGame, a mobile health (mHealth) gamification software system for the iPad, as a potential advanced technology to assess UL motor functions.
Objective: This feasibility study examines whether MoEvGame can assess children’s whole-limb movement, fine motor skills, manual dexterity, and bimanual coordination. The specific aims were to (1) design and develop novel mHealth gamified software tools to examine theory-driven features of UL movement, (2) analyze spatiotemporal game data with new algorithms and statistical techniques to quantify movement performance as a parameter of speed, accuracy, and precision, and (3) validate assessment methods with healthy participants from schools.
Methods: Elementary school children (N=31, median 9.0, IQR 4.0-14.0 years old) participated by playing 5 games. The game tasks were focused on key features of skilled motor control: (1) whole limb reaching, (2) fine motor control and manual dexterity, and (3) bilateral coordination. Spatiotemporal game data were transferred and stored in a cloud-based data management server for further processing and analysis. We applied change point detection (ie, the pruned exact linear time method), signal processing techniques, and other algorithms to calculate movement speed and accuracy from spatiotemporal parameters. Different statistical methods (ie, Pearson correlation, mean, standard deviation, P value, 95% confidence interval) were used to compare speed-accuracy tradeoffs and evaluate the relationship between age and motor performance.
Results: A negative correlation was identified between speed and accuracy in the whole limb movement (r=–0.30 to –0.42). Significant relationships between age and upper limb performance were found: older participants exhibited lower errors with faster completion times compared to younger participants. Significant differences in bimanual coordination were found related to phase synchronization (in-phase congruent [mean 28.85, SD 18.97] vs antiphase congruent [mean 112.64, SD 25.82] and in-phase mirrored [mean 23.78, SD 16.07] vs antiphase mirrored [mean 121.39, SD 28.19]). Moreover, the average speed (revolutions per second) and travel distance (m) of the in-phase mode were significantly higher than those of the antiphase coordination.
Conclusions: Results of this feasibility study show that spatiotemporal data captured from the mHealth app can quantify motor performance. Moving beyond traditional assessments, MoEvGame incorporates gamification into ubiquitous and accessible technology as a fast, flexible, and objective tool for UL motor assessment
Feel the Pressure? Normative Pressures as a Unifying Mechanism for Relational Antecedents of Employee Turnover
No full textRelational perspectives on turnover antecedents have gained momentum in recent years, highlighting three distinct relational forces underlying employees\u27 turnover decisions—notably, job embeddedness, social capital, and turnover contagion. However, these distinct perspectives are typically examined independent of one another, with little theoretical integration or holistic understanding of the shared mechanisms through which these relational antecedents operate on turnover intentions and behavior. We propose a conceptual model integrating the three types of relational antecedents (specifying their unique effects), while positing normative pressures from work and nonwork relationships as a fundamental consideration underlying quit decisions that translates their effects on leaving. Our model tests find support for this common mediator, even when controlling for traditional mediating mechanisms (i.e., job attitudes and perceived alternatives). Our tests also include important cultural considerations, allowing for comparisons between national cultures in our sample of nearly 700 surveyed employees and their subsequent quit intentions and behaviors, spanning the USA, Hong Kong, and China. Our tests revealed that on- and off-the-job embeddedness reduces quit propensity while prospective colleague turnover boosts that propensity. Path analyses further determined that normative pressures predict quit propensity (beyond attitudes and alternatives), and that such pressures mediate how job embeddedness and prospective coworker turnover influence quit propensity. We tease apart these effects across national cultures and discuss theoretical and practical implications of our findings
The Future of Sanctuary
No full textIn the summer of 1984, a caravan of vehicles full of religious activists sped across the United States. Moving from Tucson to Los Angeles to Denver and finally ending in Detroit, this self-styled Sanctuary Freedom Train was transporting a Salvadoran family of four that had fled their war-torn country and arrived in the United States seeking political asylum. Raul and Valeria Gonzalez had escaped with their two children after Raul, a teacher, had been arrested and beaten by government soldiers and threatened with worse if he were to continue his literacy work among the country\u27s poor. The Gonzalez family found refuge in Detroit\u27s St. Rita\u27s Catholic Church, where people of faith had pledged to offer sanctuary to migrants who had been unduly denied asylum by the American government. Once settled in his new temporary home, Raul became an organizer himself, inviting congregations across the country to join a national movement for migrant justice. As he noted a year after disembarking the Sanctuary Freedom Train, solidarity is doing whatever is needed to stop the suffering of others
The influence of historical climate cycles on the diversification and demography of species from the Neotropical lizard group \u3cem\u3eAnolis chrysolepis\u3c/em\u3e
No full textHistorical shifts in climate have significantly influenced the establishment of ecosystems and the evolution of species. Phylogeographical studies integrated with niche modelling can provide insights into divergence events and demography. This study explores the evolutionary history, demographic patterns, and spatiotemporal dynamics of seven South American lizard species of the Anolis chrysolepis species group, which has been proposed to be strongly impacted by Pleistocene climatic fluctuations under the Refugia Hypothesis. We utilized mitochondrial and nuclear DNA sequences to delineate lineages, estimate divergence times, and examine demographic dynamics. Ecological niche models were employed to assess historical range shifts and identify climatic stability zones during the Quaternary. Our results identified 40 distinct lineages within the group. The species A. chrysolepis and A. tandai exhibited the highest lineage diversity, with seven and 12 lineages, respectively, while others showed fewer divergences. In the Cerrado savannas, species diversification aligns with Miocene geological and climatic changes, supporting the plateau/depression theory. In Amazonia, diversification during the Miocene was tied to Andean orogenesis, with Pleistocene range expansions influenced by climatic cycles. All species demonstrated demographic declines during the Pleistocene. Niche models highlighted stability areas in the Cerrado, and western and northern Amazonia, consistent with proposed refugia. These findings offer new insights into the biogeographical and evolutionary processes shaping biodiversity in these megadiverse regions
