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The dispersal of modern humans from Africa is now well documented with genetic data that track population history, as well as gene flow between populations. Phenetic skeletal data, such as cranial and pelvic morphologies, also exhibit a dispersal-from-Africa signal, which, however, tends to be blurred by the effects of local adaptation and in vivo phenotypic plasticity, and that is often deteriorated by postmortem damage to skeletal remains. These complexities raise the question of which skeletal structures most effectively track neutral population history. The cavity system of the inner ear (the so-called bony labyrinth) is a good candidate structure for such analyses. It is already fully formed by birth, which minimizes postnatal phenotypic plasticity, and it is generally well preserved in archaeological samples. Here we use morphometric data of the bony labyrinth to show that it is a surprisingly good marker of the global dispersal of modern humans from Africa. Labyrinthine morphology tracks genetic distances and geography in accordance with an isolation-by-distance model with dispersal from Africa. Our data further indicate that the neutral-like pattern of variation is compatible with stabilizing selection on labyrinth morphology. Given the increasingly important role of the petrous bone for ancient DNA recovery from archaeological specimens, we encourage researchers to acquire 3D morphological data of the inner ear structures before any invasive sampling. Such data will constitute an important archive of phenotypic variation in present and past populations, and will permit individual-based genotype-phenotype comparisons.

Despite ensuring the integrity of bogie frames for railway vehicles via nondestructive inspections during periodic maintenance, the possibility of fatigue cracks occurring at locations other than the predetermined inspection points cannot be dismissed. Therefore, fatigue cracks can be prevented more efficiently by assessing the overall degree of fatigue damage to the entire bogie frame and determining the results via nondestructive inspections. In this study, dynamic stresses in the bogie frame during running were estimated via finite element dynamic analysis by using the axle box acceleration as input, and the degree of fatigue damage and life were calculated from the waveform of the estimated stresses. Furthermore, we developed a bogie frame fatigue prediction system based on a high‐speed and high‐precision stress calculation method. The developed system visualized the overall relative life. [ABSTRACT FROM AUTHOR]

The Jomon period of Japan is characterised by a unique combination of sedentary and hunting/gathering lifestyles, spanning for more than 10,000 years from the final Pleistocene to the Holocene. The transition from the preceding Palaeolithic period to the Jomon period is known to have begun with the appearance of pottery usage. However, knowledge of the genetic background of the Jomon people is still limited. We aimed to determine the population-scale complete mitogenome sequences of the Initial Jomon human remains and compare the occurrence of mitochondrial haplogroups in the Jomon period from temporal and regional perspectives. For human remains dated to 8200–8600 cal BP, we determined their complete mitogenome sequences using target enrichment-coupled next-generation sequencing. We successfully obtained the complete mitogenome sequences with high depth of coverage and high concordance on consensus sequences. These sequences differed by more than three bases each, except for two individuals having completely identical sequences. Co-existence of individuals with haplogroups N9b and M7a was first observed at the same archaeological site from the Initial Jomon period. The genetic diversity within the population was not found to be low even in the Initial Jomon period. [ABSTRACT FROM AUTHOR]

Several studies are conducted to explain the differences existing between the different dental traits and the geontypes present in the ectodysplasin A receptor (EDAR). The analysis also discusses the common variation in EDAR, which acts as a genetic determinant of the shovel-shaped incisors.

This study aims to develop a wheel profile optimization procedure to minimize flange wear considering the wear evolution. To this end, the wheel wear simulation capability is integrated into the profile optimization framework such that a total material loss can be minimized under design constraints. This allows for the wear reduction to be maintained over an extended traveling distance, while an optimized profile, minimizing the frictional energy for only the initial profile, would not ensure the optimum performance after the profile wear becomes significant. Furthermore, to enable a balanced mitigation of the profile wear and surface damage, the damage index model is introduced to the weighted objective function, considering profile wear evolution. Using flange wear tests with a scaled roller test rig, wear reduction of the optimized profile is experimentally validated. The wear simulation results agree with the test data. It is demonstrated that the flange wear and tread surface damages are reduced simultaneously over an extended traveling distance using the profile optimization procedure developed in this study. [ABSTRACT FROM AUTHOR]