Objectives: Morphological integration, or the tendency for covariation, is commonly seen in complex traits such as the human face. The effects of growth on shape, or allometry, represent a ubiquitous but poorly understood axis of integration. We address the question of to what extent age and measures of size converge on a single pattern of allometry for human facial shape.
Methods: Our study is based on two large cross-sectional cohorts of children, one from Tanzania and the other from the United States (N = 7,173). We employ 3D facial imaging and geometric morphometrics to relate facial shape to age and anthropometric measures.
Results: The two populations differ significantly in facial shape, but the magnitude of this difference is small relative to the variation within each group. Allometric variation for facial shape is similar in both populations, representing a small but significant proportion of total variation in facial shape. Different measures of size are associated with overlapping but statistically distinct aspects of shape variation. Only half of the size-related variation in facial shape can be explained by the first principal component of four size measures and age while the remainder associates distinctly with individual measures.
Conclusions: Allometric variation in the human face is complex and should not be regarded as a singular effect. This finding has important implications for how size is treated in studies of human facial shape and for the developmental basis for allometric variation more generally.
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http://dx.doi.org/10.1002/ajpa.23356 | DOI Listing |
Proc Natl Acad Sci U S A
February 2025
Department of Psychology, Princeton University, Princeton, NJ 08540.
Traditional gendered arrangements-norms, roles, prejudices, and hierarchies-shape every human life. Associated harms are primarily framed as women's issues due to more severe consequences women face. Yet, gendered arrangements also shape 's relationships, career paths, and health.
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January 2025
Department of Musculoskeletal & Ageing Science, Institute of Life Course & Medical Sciences (ILCaMS) and Human Anatomy Resource Centre (HARC), Education Directorate, University of Liverpool, Liverpool, UK.
The importance of interactions between neighbouring rapidly growing tissues of the head during development is recognised, yet this competition for space remains incompletely understood. The developing structures likely interact through a variety of mechanisms, including directly genetically programmed growth, and are mediated via physiological signalling that can be triggered by structural interactions. In this study, we aimed to investigate a different but related potential mechanism, that of simple mechanical plastic deformation of neighbouring structures of the head in response to soft tissue expansion during human postnatal ontogeny.
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January 2025
Department of Precision Instrument, Tsinghua University, Beijing 100084, China.
The increasing reliance on deep neural network-based object detection models in various applications has raised significant security concerns due to their vulnerability to adversarial attacks. In physical 3D environments, existing adversarial attacks that target object detection (3D-AE) face significant challenges. These attacks often require large and dispersed modifications to objects, making them easily noticeable and reducing their effectiveness in real-world scenarios.
View Article and Find Full Text PDFBiosensors (Basel)
December 2024
School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, China.
Spheroids, as three-dimensional (3D) cell aggregates, can be prepared using various methods, including hanging drops, microwells, microfluidics, magnetic manipulation, and bioreactors. However, current spheroid manufacturing techniques face challenges such as complex workflows, the need for specialized personnel, and poor batch reproducibility. In this study, we designed a support-free, 3D-printed microwell chip and developed a compatible low-cell-adhesion process.
View Article and Find Full Text PDFBehav Sci (Basel)
January 2025
Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia.
As individuals with a cleft lip and palate (CLP) transition into adulthood, they face unique employment challenges related to income, job stability, and fewer career options. This study explored these challenges through two focus group discussions with 19 participants (aged 21-38), primarily women, to understand their employment experiences. Thematic analysis revealed the following three main themes: (1) physical factors, (2) psychosocial factors, and (3) overcoming employment challenges, with nine sub-themes including speech, hearing, appearance, health, childhood experiences, societal expectations, lack of self-confidence, communication improvement, and self-esteem building.
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