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2. A unified energy optimality criterion predicts human navigation paths and speeds

Author

Brown, Geoffrey L., Seethapathi, Nidhi, and Srinivasan, Manoj

Subjects
Quantitative Biology - Neurons and Cognition, Nonlinear Sciences - Adaptation and Self-Organizing Systems
Abstract

Navigating our physical environment requires changing directions and turning. Despite its ecological importance, we do not have a unified theoretical account of non-straight-line human movement. Here, we present a unified optimality criterion that predicts disparate non-straight-line walking phenomena, with straight-line walking as a special case. We first characterized the metabolic cost of turning, deriving the cost landscape as a function of turning radius and rate. We then generalized this cost landscape to arbitrarily complex trajectories, allowing the velocity direction to deviate from body orientation (holonomic walking). We used this generalized optimality criterion to mathematically predict movement patterns in multiple contexts of varying complexity: walking on prescribed paths, turning in place, navigating an angled corridor, navigating freely with end-point constraints, walking through doors, and navigating around obstacles. In these tasks, humans moved at speeds and paths predicted by our optimality criterion, slowing down to turn and never using sharp turns. We show that the shortest path between two points is, counterintuitively, often not energy optimal, and indeed, humans do not use the shortest path in such cases. Thus, we have obtained a unified theoretical account that predicts human walking paths and speeds in diverse contexts. Our model focuses on walking in healthy adults; future work could generalize this model to other human populations, other animals, and other locomotor tasks.

Published
2020
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6. Paternal Identity, Maternal Gatekeeping, and Father Involvement

Author

McBride, Brent A., Brown, Geoffrey L., and Bost, Kelly K.

Abstract

The purpose of this study was to examine whether mothers' beliefs about the role of the father may contribute to mothers influencing the quantity of father involvement in their children's lives. Participants were 30 two-parent families with children between the ages of 2 and 3 years. A combination of self-report and interview data were collected from both mothers and fathers. Results from multiple regression analyses indicated that fathers' perceived investments in their parental roles and actual levels of paternal involvement are moderated by mothers' beliefs about the role of the father. Findings are discussed in terms of implications for future research on parenting identity and maternal gatekeeping as well as the development of parenting programs for fathers.

Published
2005
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7. Conceptual comparison of constructs as first step in data harmonization:Parental sensitivity, child temperament, and social support as illustrations

Author

Verhage, Marije L., Schuengel, Carlo, Holopainen, Annaleena, Bakermans-Kranenburg, Marian J., Bernier, Annie, Brown, Geoffrey L., Madigan, Sheri, Roisman, Glenn I., Vaever, Mette S., Wong, Maria S., Verhage, Marije L., Schuengel, Carlo, Holopainen, Annaleena, Bakermans-Kranenburg, Marian J., Bernier, Annie, Brown, Geoffrey L., Madigan, Sheri, Roisman, Glenn I., Vaever, Mette S., and Wong, Maria S.

Abstract

This article presents a strategy for the initial step of data harmonization in Individual Participant Data syntheses, i.e., making decisions as to which measures operationalize the constructs of interest - and which do not. This step is vital in the process of data harmonization, because a study can only be as good as its measures. If the construct validity of the measures is in question, study results are questionable as well. Our proposed strategy for data harmonization consists of three steps. First, a unitary construct is defined based on the existing literature, preferably on the theoretical framework surrounding the construct. Second, the various instruments used to measure the construct are evaluated as operationalizations of this construct, and retained or excluded based on this evaluation. Third, the scores of the included measures are recoded on the same metric. We illustrate the use of this method with three example constructs focal to the Collaboration on Attachment Transmission Synthesis (CATS) study: parental sensitivity, child temperament, and social support. This process description may aid researchers in their data pooling studies, filling a gap in the literature on the first step of data harmonization.Data harmonization in studies using combined datasets is of vital importance for the validity of the study results.We have developed and illustrated a strategy on how to define a unitary construct and evaluate whether instruments are operationalizations of this construct as the initial step in the harmonization process.This strategy is a transferable and reproducible method to apply to the data harmonization process. (C) 2022 The Author(s). Published by Elsevier B.V.

Published
2022

8. Conceptual comparison of constructs as first step in data harmonization: Parental sensitivity, child temperament, and social support as illustrations

Author

Verhage, Marije L., primary, Schuengel, Carlo, additional, Holopainen, Annaleena, additional, Bakermans-Kranenburg, Marian J., additional, Bernier, Annie, additional, Brown, Geoffrey L., additional, Madigan, Sheri, additional, Roisman, Glenn I., additional, Vaever, Mette S., additional, Wong, Maria S., additional, Barone, Lavinia, additional, Behrens, Kazuko Y., additional, Behringer, Johanna, additional, Bovenschen, Ina, additional, Cassibba, Rosalinda, additional, Cassidy, Jude, additional, Coppola, Gabrielle, additional, Costantini, Alessandro, additional, Dozier, Mary, additional, Ensink, Karin, additional, Fearon, R. M. Pasco, additional, Finger, Brent, additional, Hautamaki, Airi, additional, Hazen, Nancy L., additional, Ierardi, Elena, additional, Jongenelen, Inês, additional, Køppe, Simo, additional, Lionetti, Francesca, additional, Mangelsdorf, Sarah, additional, Oosterman, Mirjam, additional, Pace, Cecilia S., additional, Raby, K. Lee, additional, Crugnola, Cristina Riva, additional, Simonelli, Alessandra, additional, Spangler, Gottfried, additional, Tarabulsy, George M., additional, Væver, Mette S., additional, Verhage, Marije L., additional, Arnott, Bronia, additional, Bailey, Heidi, additional, Brice, Patrick J., additional, Brisch, Karl-Heinz, additional, Castoro, Germana, additional, Costantino, Elisabetta, additional, Cyr, Chantal, additional, George, Carol, additional, Gloger-Tippelt, Gabriele, additional, Gojman, Sonia, additional, Harder, Susanne, additional, Howes, Carollee, additional, Jacobsen, Heidi, additional, Jacobvitz, Deborah, additional, Jin, Mi Kyoung, additional, Juffer, Femmie, additional, Kazui, Miyuki, additional, Leerkes, Esther M., additional, Lyons-Ruth, Karlen, additional, McMahon, Catherine, additional, Meins, Elizabeth, additional, Millán, Salvador, additional, Murray, Lynne, additional, Nowacki, Katja, additional, Pederson, David R., additional, Priddis, Lynn, additional, Sagi-Schwartz, Avi, additional, Schoppe-Sullivan, Sarah J., additional, Solomon, Judith, additional, Speranza, Anna Maria, additional, Steele, Miriam, additional, Steele, Howard, additional, Teti, Doug M., additional, van IJzendoorn, Marinus H., additional, van Londen-Barentsen, W. Monique, additional, and Ward, Mary J., additional

Published
2022
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10. Conceptual comparison of constructs as first step in data harmonization: Parental sensitivity, child temperament, and social support as illustrations

Author

Bakermans-Kranenburg, Marian J., Barone, Lavinia, Behrens, Kazuko Y., Behringer, Johanna, Bernier, Annie, Bovenschen, Ina, Brown, Geoffrey L., Cassibba, Rosalinda, Cassidy, Jude, Coppola, Gabrielle, Costantini, Alessandro, Dozier, Mary, Ensink, Karin, Fearon, R. M. Pasco, Finger, Brent, Hautamaki, Airi, Hazen, Nancy L., Ierardi, Elena, Jongenelen, Inês, Køppe, Simo, Lionetti, Francesca, Madigan, Sheri, Mangelsdorf, Sarah, Oosterman, Mirjam, Pace, Cecilia S., Raby, K. Lee, Crugnola, Cristina Riva, Roisman, Glenn I., Schuengel, Carlo, Simonelli, Alessandra, Spangler, Gottfried, Tarabulsy, George M., Væver, Mette S., Verhage, Marije L., Wong, Maria S., Arnott, Bronia, Bailey, Heidi, Brice, Patrick J., Brisch, Karl-Heinz, Castoro, Germana, Costantino, Elisabetta, Cyr, Chantal, George, Carol, Gloger-Tippelt, Gabriele, Gojman, Sonia, Harder, Susanne, Howes, Carollee, Jacobsen, Heidi, Jacobvitz, Deborah, Jin, Mi Kyoung, Juffer, Femmie, Kazui, Miyuki, Leerkes, Esther M., Lyons-Ruth, Karlen, McMahon, Catherine, Meins, Elizabeth, Millán, Salvador, Murray, Lynne, Nowacki, Katja, Pederson, David R., Priddis, Lynn, Sagi-Schwartz, Avi, Schoppe-Sullivan, Sarah J., Solomon, Judith, Speranza, Anna Maria, Steele, Miriam, Steele, Howard, Teti, Doug M., van IJzendoorn, Marinus H., van Londen-Barentsen, W. Monique, Ward, Mary J., Holopainen, Annaleena, and Vaever, Mette S.

Published
2022
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11. Romantic Relationship Commitment Behavior Among Emerging Adult African American Men

Author

Kogan, Steven M., Yu, Tianyi, and Brown, Geoffrey L.

Subjects
Article
Abstract

Contextual and intrapersonal factors affecting the development of African American men's romantic relationship commitment-related behavior were investigated. Socioeconomic disadvantage during early adolescence was hypothesized to predict harsh, unsupportive parenting practices. Harsh parenting was hypothesized to result in youths' emotion-regulation difficulties, indicated by elevated levels of anger during mid-adolescence, particularly when men were exposed to racial discrimination. Young African American men's anger during mid-adolescence, a consequence of harsh, unsupportive parenting and racial discrimination, was expected to predict commitment-related behavior. Hypotheses were tested with a sample of rural African American men participating in a panel study from the ages of 11 through 21. Data from teachers, parents, and youths were integrated into a multi-reporter measurement plan. Results confirmed the hypothesized associations. Study findings indicate that the combination of harsh parenting and racial discrimination is a powerful antecedent of young men's commitment-related behavior. Anger across mid-adolescence mediated this interaction effect.

Published
2016

13. The Evolution of Large-Amplitude Internal Gravity Wavepackets

Author

BROWN, Geoffrey L., SUTHERLAND, Bruce, Association Française de Mécanique, and Service irevues, irevues

Subjects
[PHYS.MECA]Physics [physics]/Mechanics [physics], [PHYS.MECA] Physics [physics]/Mechanics [physics]
Abstract

Colloque avec actes et comité de lecture. Internationale.; International audience; The interaction between internal gravity wavepackets and their associated wave-induced mean flow is shown to dominate their weakly nonlinear evolution at early times. Sufficiently large amplitude waves either grow in amplitude as the wavepacket narrows or decrease in amplitude as the wavepacket broadens due to nonlinearly enhanced dispersion depending on whether the frequency is respectively greater or less than the frequency of internal waves having the fastest vertical group velocity. This is true whether the waves are horizontally periodic or horizontally compact. In non-uniformly stratified fluid, the weakly nonlinear effect acts to enhance or retard transmission of the waves across a localized evanescent region depending upon the wave amplitude and relative frequency.

Published
2007

16. A Comparative Analysis of the Protein Components of Plasma Membranes Isolated from Differentiated and Undifferentiated Mouse Neuroblastoma Cells in Tissue Culture.

Author

Garvican, John H. and Brown, Geoffrey L.

Subjects
*CELL membranes, *NEUROBLASTOMA, *TISSUE culture, *POLYACRYLAMIDE gel electrophoresis, *AMINO acids, *GLYCOSYLATION, *PROTEIN synthesis
Abstract

The plasma membranes of the cells of mouse neuroblastoma clone NB41A, were isolated without fixation by hardening procedures and were characterised by their enzyme activities and by their morphology in the light and electron microscopes. The membranes were prepared from two kinds of differentiated monolayer cultures; one in which the cells were induced to form long axon-like processes by the addition of N6,O2′-dibutyryladenosine 3′:5′-monophosphate to the culture medium, and the other in which the cells were induced to form processes by the addition of 5-bromo-2′-deoxyuridine. The proteins from the solubilised membranes were compared with similar preparations from the membranes of undifferentiated cells, grown in suspension, by sodium dodecylsulphate polyacrylamide gel electrophoresis, using the incorporation of radioactive amino acids and L-fucose into proteins in the cultures to follow the differences in the patterns of polypeptide synthesis and glycosylation of the membrane proteins. The differentiated cells induced with either induced show an increased incorporation of L-fucose into two distinct components with molecular weights of 60000 and 70000. The two types of induced cells differ from each other in that N6,O2′ -dibutyryladenosine 3′: 5′-monophosphate stimulates both glycosylation and protein synthesis, with a relative increase in the low molecular weight proteins, but 5-bromo-2′-deoxyuridine stimulates mostly increased glycosylation of the membrane proteins. [ABSTRACT FROM AUTHOR]

Published
1977
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