Anthroengineering: an independent interdisciplinary field

In recent decades, funding agencies, institutes and professional bodies have recognized the profound benefits of transdisciplinarity in tackling targeted research questions. However, once questions are answered, the previously abundant support often dissolves. As such, the long-term benefits of these transdisciplinary approaches are never fully achieved. Over the last several decades, the integration of anthropology and engineering through inter- and multidisciplinary work has led to advances in fields such as design, human evolution and medical technologies. The lack of formal recognition, however, of this transdisciplinary approach as a unique entity rather than a useful tool or a subfield makes it difficult for researchers to establish laboratories, secure permanent jobs, fund long-term research programmes and train students in this approach. To facilitate the growth and development and witness the long-term benefits of this approach, we propose the integration of anthropology and engineering be recognized as a new, independent field known as anthroengineering . We present a working definition for anthroengineering and examples of how anthroengineering has been used. We discuss the necessity of recognizing anthroengineering as a unique field and explore potential novel applications. Finally, we discuss the future of anthroengineering, highlighting avenues for moving the field forward

Technical note: A freeware, equitable approach to dental topographic analysis

Dental topographic analysis has proved a valuable tool for quantifying dental morphology. Established workflows often use proprietary software for pre-processing dental surfaces, rendering the method expensive and inaccessible to many. This study explores the use of freeware pre-processing alternatives. We tested 4 decimation tools and 13 smoothing tools across 7 different freeware packages. Surfaces generated via proprietary software could not be replicated, but it was possible to obtain statistically similar measurements using freeware. Based on this investigation, we propose a freeware workflow for researchers to conduct dental topographic analysis, with the expectation that their results will be comparable to that obtained through proprietary methods

The effects of femoral metaphyseal morphology on growth plate biomechanics in juvenile chimpanzees and humans

The distal femoral metaphyseal surface presents dramatically different morphologies in juvenile extant hominoids—humans have relatively flat metaphyseal surfaces when compared with the more complex metaphyseal surfaces of apes. It has long been speculated that these different morphologies reflect different biomechanical demands placed on the growth plate during locomotor behaviour, with the more complex metaphyseal surfaces of apes acting to protect the growth plate during flexed-knee behaviours like squatting and climbing. To test this hypothesis, we built subject-specific parametric finite-element models from the surface scans of the femora of five Pan and six Homo juveniles. We then simulated the loading conditions of either a straight-leg or flexed-knee gait and measured the resulting stresses at the growth plate. When subjected to the simulated flexed-knee loading conditions, both the maximum and mean von Mises stresses were significantly lower in the Pan models than in the Homo models. Further, during these loading conditions, von Mises stresses were strongly negatively correlated with ariaDNE, a measure of complexity of the metaphyseal surface. These results indicate that metaphyseal surface morphology has a robust effect on growth plate mechanics

Were Neandertal Humeri Adapted for Spear Thrusting or Throwing? A Finite Element Study

An ongoing debate concerning Neandertal ecology is whether or not they utilized long range weaponry. The anteroposteriorly expanded cross-section of Neandertal humeri have led some to argue they thrusted their weapons, while the rounder cross-section of Late Upper Paleolithic modern human humeri suggests they threw their weapons. We test the hypothesis that Neandertal humeri were built to resist strains engendered by thrusting rather than throwing using finite element models of one Neandertal, one Early Upper Paleolithic (EUP) human and three recent human humeri, representing a range of cross-sectional shapes and sizes. Electromyography and kinematic data and articulated skeletons were used to determine muscle force magnitudes and directions during three positions of spear throwing and three positions of spear thrusting. Maximum von Mises strains were determined at the 35% and 50% cross-sections of all models. During throwing and thrusting, von Mises strains produced by the Neandertal humerus fell roughly within or below those produced by the modern human humeri. The EUP humerus performed similarly to the Neandertal, but slightly poorer during spear thrusting. This implies the Neandertal and EUP human humeri were just as well adapted at resisting strains during throwing as recent humans and just as well or worse adapted at resisting strains during thrusting as recent humans. We also did not find any correlation between strains and biomechanical metrics used to measure humeral adaptation in throwing and thrusting (retroversion angle, Imax/Imin, J). These results failed to support our hypothesis and suggest they were capable of using long distance weaponry

Microscopic Modeling of Driver Behavior Based on Modifying Field Theory for Work Zone Application

Because many freeways in the U.S. and abroad are being reconstructed or rehabilitated, it becomes increasingly important to plan and design freeway work zones with the utmost in safety and efficiency. Central to the effective design of work zones is being able to understand how drivers behave as they approach and enter a work zone area. While simple and complex microscopic models have been used over the years to analyze driver behavior, most models were not designed for application in work zones and thus do not capture the interdependencies between lane-changing and car-following vehicle movements along with the drivers’ cognitive and physical characteristics. With the use of psychology’s field theory, this dissertation develops a framework for creating vector-based, explanatory, deterministic microscopic models, to enhance our understanding of driver behavior in work zones and better aid freeway planners and designers. In field theory, an agent (i.e. the driver) views a field (i.e. the area surrounding the vehicle) filled with stimuli and perceives forces associated with each stimuli once these stimuli are internalized. Based on this theory, the new modeling framework, Modified Field Theory (MFT), is designed to directly incorporate drivers’ perceptions to roadway stimuli along with vehicle movements for drivers of different cognitive and physical abilities. From this framework, specific microscopic models, such as a simple freeway work zone car following model, can be created. It is postulated that models derived from this framework would more accurately reflect the driver decision-making process, naturally modeling the effects of external stimuli such as innovative geometric configurations, lane closures, and technology applications such as variable message boards. A simple freeway work zone car following model was created using the MFT framework. Two MFT car-following agents were created and calibrated. The second agent (Agent 2) followed the first agent (Agent 1) through a one-lane segment of freeway. Car-following data for Agent 2 was plotted on a graph of relative speed vs. distance to the lead vehicle, showing car-following behavior. Car-following behavior for Agent 2 was validated against Federal Highway Administration (FHWA) Turner Fairbank Highway Research Center (TFHRC) Living Laboratory data for simple freeway work zone car-following (Driver 15). The car-following behavior of Agent 2 replicated the “spiraling” trend observed in Driver 15. Unlike other models (such as Wiedemann), this model does not ‘force’ these trends to occur; these trends occur naturally, as a result of the perception-reaction time delay and the nature of the forces involved. Additionally, unusual car following trends reported for Driver 15 were replicated in Modified Field Theory when conditions surrounding each event were synthetically recreated. Results demonstrated that the Modified Field Theory framework can successfully replicate the process by which a driver scans the driving environment and reacts to their surroundings. Microscopic models can successfully be created using this framework. Results demonstrated that models created from this framework naturally recreate behavioral trends observed in empirical data, and that these models are capable of replicating driving behavior in unusual scenarios, such as the car following behavior of a subject vehicle when the lead vehicle has a strong sudden acceleration event. Before this model can be applied to work zones, other calibration and validation efforts are required

Evaluation of New England Bridges for Bat Roosting Including Methodology and Case Studies

Bats are known and documented to use bridge structures as roosts in various locations throughout the United States and abroad, but there is limited knowledge of how bats use bridges in New England. Significant population declines due to White-Nose Syndrome have resulted in several bat species being listed as state or federally threatened or endangered. If bats are using bridges as roosts, significant effort is required to ensure they are not disturbed or harmed during construction or maintenance work, requiring knowledge of assessment methods to identify likely roost locations in bridges. This thesis describes a two summer study evaluating the bat roosting potential in New England bridges. During this study, 191 bridges were rapidly screened throughout New England for bat roosting potential, with eighteen selected for more detailed evaluations. Various monitoring techniques to determine bat roosting potential were assessed at each bridge evaluated, including acoustic monitoring and analyses, infrared imaging, borescope inspection, visual inspection, emergence studies, and guano testing for species identification. The current federal form required to assess bat roosting in bridges slated for construction work was assessed for its appropriateness in the New England region. A supplemental form has been developed through this study that is recommended to be used in conjunction with the federal form to better assess roosting potential in New England bridges. Training and collaboration is also recommended for personnel completing forms and inspectors familiar with state bridges. When the study began, there was only one known bat bridge roost in New England known. After this two summer study, thirteen bridges have been positively identified as bat roosting sites in New England, with possible roosting at several other bridges. Information gathered through this study on bat roosting potential in bridges and the various monitoring techniques evaluated to positively identify bat roosting in bridges can be used as guidance for state Transportation Agencies developing protocol for construction at potential roosting sites

Light pollution: a case for federal regulation

The purpose of this thesis is to examine the body of evidence concerning light pollution and exposure to artificial light and determine if the scientific research warrants regulatory oversight in the United States. The first question that guided this effort was: Does improper artificial lighting and exposure to light-at-night constitute a risk to human health and safety? The follow up question being: Is light pollution a concern to ecological systems, and if so to what extent? A comprehensive literature review was conducted to ascertain the status of the research—if any—in these two areas and what the findings were. The overarching purpose of this thesis was to answer the primary question: Does the scientific research on light pollution and exposure to light-at-night exposure make a case for regulatory oversight, within the mandate of the EPA? The questions were illuminated by conducting a thorough literature review, doing an informal email survey, and by in-depth interviews with people researching artificial light and with individuals in the EPA. The study concluded that there is no ready consensus to be reached in this area. Such a disparate topic as light pollution does not readily lend itself to an easy answer. However, the findings show that light pollution and light-at-night exposure do have some negative impact. This is especially true in regards to the night sky and the biota. Whether the EPA should be involved in regulating it is not entirely clear. Their mission statement leads one to presume that certain effects of light pollution do fall under their mandate. More research to quantify the effects of artificial light on humans is critically needed to show causation between artificial light exposure and health problems

Detecting and Characterizing the Fabella with High Frame-Rate Ultrasound Imaging

The fabella is a sesamoid bone usually located in the tendon of the lateral head of the gastrocnemius muscle, behind the knee joint. Prevalence rates in human populations vary widely with an average of 42.5% people having a fabella. Clinically, it is associated with a number of knee ailments, most notably the osteoarthritis of the knee and generalized knee pain (i.e., fabella syndrome). As the function of the fabella remains unknown, the biomechanical consequences of fabella presence/absence can only be speculated. Successfully detecting the fabella, measuring its size and determining its shape, are off importance for clinical and evolutionary researchers. In this work, we compare plane wave imaging with conventional focused imaging and evaluate their performance for detecting and characterizing the fabella

Food mechanical properties and dietary ecology

Interdisciplinary research has benefitted the fields of anthropology and engineering for decades: a classic example being the application of material science to the field of feeding biomechanics. However, after decades of research, discordances have developed in how mechanical properties are defined, measured, calculated, and used due to disharmonies between and within fields. This is highlighted by “toughness,” or energy release rate, the comparison of incomparable tests (i.e., the scissors and wedge tests), and the comparison of incomparable metrics (i.e., the stress and displacement‐limited indices). Furthermore, while material scientists report on a myriad of mechanical properties, it is common for feeding biomechanics studies to report on just one (energy release rate) or two (energy release rate and Young's modulus), which may or may not be the most appropriate for understanding feeding mechanics. Here, I review portions of materials science important to feeding biomechanists, discussing some of the basic assumptions, tests, and measurements. Next, I provide an overview of what is mechanically important during feeding, and discuss the application of mechanical property tests to feeding biomechanics. I also explain how 1) toughness measures gathered with the scissors, wedge, razor, and/or punch and die tests on non‐linearly elastic brittle materials are not mechanical properties, 2) scissors and wedge tests are not comparable and 3) the stress and displacement‐limited indices are not comparable. Finally, I discuss what data gathered thus far can be best used for, and discuss the future of the field, urging researchers to challenge underlying assumptions in currently used methods to gain a better understanding between primate masticatory morphology and diet