Beyond Mixing-length Theory: a step toward 321D

We examine the physical basis for algorithms to replace mixing-length theory (MLT) in stellar evolutionary computations. Our 321D procedure is based on numerical solutions of the Navier-Stokes equations. These implicit large eddy simulations (ILES) are three-dimensional (3D), time-dependent, and turbulent, including the Kolmogorov cascade. We use the Reynolds-averaged Navier-Stokes (RANS) formulation to make concise the 3D simulation data, and use the 3D simulations to give closure for the RANS equations. We further analyze this data set with a simple analytical model, which is non-local and time-dependent, and which contains both MLT and the Lorenz convective roll as particular subsets of solutions. A characteristic length (the damping length) again emerges in the simulations; it is determined by an observed balance between (1) the large-scale driving, and (2) small-scale damping. The nature of mixing and convective boundaries is analyzed, including dynamic, thermal and compositional effects, and compared to a simple model. We find that (1) braking regions (boundary layers in which mixing occurs) automatically appear {\it beyond} the edges of convection as defined by the Schwarzschild criterion, (2) dynamic (non-local) terms imply a non-zero turbulent kinetic energy flux (unlike MLT), (3) the effects of composition gradients on flow can be comparable to thermal effects, and (4) convective boundaries in neutrino-cooled stages differ in nature from those in photon-cooled stages (different P\'eclet numbers). The algorithms are based upon ILES solutions to the Navier-Stokes equations, so that, unlike MLT, they do not require any calibration to astronomical systems in order to predict stellar properties. Implications for solar abundances, helioseismology, asteroseismology, nucleosynthesis yields, supernova progenitors and core collapse are indicated.Comment: 22 pages, 4 figures, 2 tables; significantly re-written, critique of Pasetto, et al. model added, accepted for publication by Ap

Proposed Community Action Plan for Casa Cornelia Law Center

Casa Cornelia and scores of other public and private agencies rely on interpreters and translators for communicating with immigrants and their communities. Volunteer support overcomes language barriers and ensures that all clients have access to support services in a culturally and linguistically appropriate manner. Unfortunately, there is often a lack of qualified volunteer interpreters and translators available, most acutely for its Somali clients, which comprise the largest percentage of its Asylum Program’s caseload. This paper considers possible solutions to the insufficient number of volunteers that are currently available to Casa Cornelia.https://digital.sandiego.edu/npi-bpl-communityengagement/1000/thumbnail.jp

Proposed Community Action Plan for Casa Cornelia Law Center

Casa Cornelia and scores of other public and private agencies rely on interpreters and translators for communicating with immigrants and their communities. Volunteer support overcomes language barriers and ensures that all clients have access to support services in a culturally and linguistically appropriate manner. Unfortunately, there is often a lack of qualified volunteer interpreters and translators available, most acutely for its Somali clients, which comprise the largest percentage of its Asylum Program’s caseload. This paper considers possible solutions to the insufficient number of volunteers that are currently available to Casa Cornelia.https://digital.sandiego.edu/npi-bpl-communityengagement/1000/thumbnail.jp

Computational design and selection of optimal organic photovoltaic materials

Conjugated organic polymers are key building blocks of low-cost photovoltaic materials. We have examined over 90 000 copolymers using computational predictions to solve the "inverse design" of molecular structures with optimum properties for highly efficient solar cells (specifically matching optical excitation energies and excited-state energies). Our approach, which uses a genetic algorithm to search the space of synthetically accessible copolymers of six or eight monomer units, yields hundreds of candidate copolymers with predicted efficiencies over 8% (the current experimental record), including many predicted to be over 10% efficient. We discuss trends in polymer sequences and found in the most frequent monomers and dimers in these highly efficient targets and derive design rules for the selection of appropriate donor and acceptor molecules. We show how additional computationally intensive filtering steps can be used, for example, to eliminate targets likely to have poor hole mobilities. Our method effectively targets optimum electronic structure and optical properties far more efficiently than time-consuming serial experiments or computational studies and can be applied to similar problems in other areas of materials science

A validation of the workplace dignity scale : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Psychology at Massey University, Manawatū, New Zealand

This thesis was published under a Creative Commons Attribution 4.0 International (CC BY 4.0) license as: Scott-Campbell, C., & Williams, M. (2020). Validating the Workplace Dignity Scale. Collabra: Psychology, 6(1), 31. http://doi.org/10.1525/collabra.337Workplace Dignity has long been the subject of scholarly enquiry, although until recently the body of research has been dominated by ethnographic work. Recently, Thomas and Lucas (2019) developed the first quantitative, direct measure of perceptions of workplace dignity: the Workplace Dignity Scale (WDS). Given the importance of understanding dignity in the workplace, this study sought to replicate the initial scale validation study conducted by Thomas and Lucas, so as to confirm the reliability and validity of the scale prior to its future applied and scholarly use. Moreover, the current study contributes to the ongoing methodological reform of psychology towards a transparent and rigorous science by preregistering the method and analysis script prior to collecting data. A large sample of workers (N = 853) from the United States were recruited through Prolific Academic and completed an online questionnaire that included the WDS, as well as theoretically related scales (e.g., workplace incivility). Confirmatory factor analyses indicated that the model specified by Thomas and Lucas had reasonable global fit and estimates of reliability (ωt) indicated that the two main factors of the scale, Dignity and Indignity, had high internal consistency. Nomological analyses revealed that the Dignity factor of the WDS was significantly correlated in the expected directions with theoretically related variables. Furthermore, the Dignity and Indignity factors of the WDS were found to highly correlate with one another, posing questions as to whether the two factors are qualitatively different phenomena as was argued by Thomas and Lucas. It is concluded that the WDS is a promising tool for measuring workplace dignity although refinement of the proposed measurement model may be necessary

The Effects of Dual-Tasking on Fall Risks in Adults with Brain Injury

Clinical Scenario: Dual-tasking combines both physical and cognitive components into one therapeutic intervention. There has been limited research on the benefits of dual tasking in relation to fall risks in adults with brain injury. Currently, it is common for various therapy interventions to spend the majority of time targeting physical or cognitive components, but not both at once. After appraisal, a total of five articles were used. These included two level I studies involving a high-quality randomized control trial and a meta-analysis, two level II studies that were both small-scale randomized control trials, and one level IV study that was a case study. The clinical bottom lines provided stated that strong evidence suggests that dual-tasking decreases fall risks in adults with brain injury, effective interventions ranged from 3 times per week for 60 minutes over 8 weeks to 7 times per week for 15 minutes over 1 week, and for adults with brain injuries, there is potential for carryover into everyday life after dual-tasking activities. The recommendations for implementation stated that further research is needed to determine the effectiveness of dual-tasking for reducing fall risks and close monitoring of the effects of dual-tasking during intervention is recommended

Temporal aspects of the group cohesion-group performance relationship in an experiential computerized business simulation

Research on group cohesion has generated conflicting findings. The present study was designed to examine the temporal aspects of the reciprocal relationship between group cohesiveness and group performance. A computerized business simulation was used to examine the longitudinal aspects of this relationship, as well as the impact of a group formation method. Participants were 412 undergraduate students enrolled in a third-year business strategy class. Students formed groups to participate in a semester-long computerized business strategy simulation game. Results indicate there is a significant cyclical relationship between group cohesion and group performance. In investigating the directionality of the relationship between both constructs, the 'group performance leads to group cohesion' relationship was stronger than the inverse 'group cohesion leads to group performance' relationship. Furthermore, the group formation method was found to influence levels of group cohesion. Practical implications and suggestions for future research are discussed