Project description:The elastic modulus, or slope of the stress-strain curve, is an important metric for evaluating tissue functionality, particularly for load-bearing tissues such as tendon. The applied force can be tracked directly from a mechanical testing system and converted to stress using the tissue cross-sectional area; however, strain can only be calculated in post-processing by tracking tissue displacement from video collected during mechanical testing. Manual tracking of Verhoeff stain lines pre-marked on the tissue is time-consuming and highly dependent upon the user. This paper details the development and testing of an automated processing method for strain calculations using Harris corner detection. The automated and manual methods were compared in a dataset consisting of 97 rat tendons (48 Achilles tendons, 49 supraspinatus tendons), divided into ten subgroups for evaluating the effects of different therapies on tendon mechanical properties. The comparison showed that average percent differences between the approaches were 0.89% and -2.10% for Achilles and supraspinatus tendons, respectively. The automated approach reduced processing time by 83% and produced similar results to the manual method when comparing the different subgroups. This automated approach to track tissue displacements and calculate elastic modulus improves post-processing time while simultaneously minimizing user dependency.
Project description:In a letter to the Editor, Harris considers the eight new species of Apicomplexa that were recently identified and named to be invalid on the basis that only molecular characters were provided in the species descriptions. In this response, we counter that the species names are valid as the descriptions have met the requirements of the International Code of Zoological Nomenclature; molecular characters can be used to satisfy article 13.1.1 of the code.
Project description:The Harris line (HL), caused by bone-growth arrest and manifesting on X-rays as a radiopaque transverse line in the metaphysis of the long bones, is an indicator reflecting stress conditions such as disease or malnutrition. HL frequency has been assumed to differ between pre-modern and modern societies, as reflective of increased caloric intake and overall nutritional improvements attendant on industrialization. To determine if such a change occurred in Korea, in the present study we compared the respective HL statuses in medieval Joseon and modern Korean population samples. HLs were found in 39.4% (28/71) of the Joseon Koreans. Whereas only 27.5% (11/40) of the males showed an HL, fully 54.8% (17/31) of the females exhibited it. Notably, HLs were observed in only 16.4% (35/213) of the modern Koreans; more remarkably still, the HL rate was almost the same between the sexes, 16.7% (20/120) for the males and 16.1% (15/93) for the females. The HL frequency was much higher in the Joseon Koreans than in their modern counterparts, reflecting the improvement of nutritional status that had been achieved in the course of South Korea's modernization. This HL-frequency decrease was much more obvious in the female populations. The higher HL frequency among the Joseon females might reflect the relatively poor nutritional condition of females in pre-modern Korean society.
Project description:Aphids display extraordinary developmental plasticity in response to environmental cues. These differential responses to environmental changes may be due in part to changes in gene expression patterns. To understand the molecular basis for aphid developmental plasticity, we attempted to identify the chromatin-remodelling machinery in the recently sequenced pea aphid genome. We find that the pea aphid possesses a complement of metazoan histone modifying enzymes with greater gene family diversity than that seen in a number of other arthropods. Several genes appear to have undergone recent duplication and divergence, potentially enabling greater combinatorial diversity among the chromatin-remodelling complexes. The abundant aphid chromatin modifying enzymes may facilitate the phenotypic plasticity necessary to maintain the complex life cycle of the aphid.
Project description:Harris Hawks Optimizer (HHO) is a recent well-established optimizer based on the hunting characteristics of Harris hawks, which shows excellent efficiency in solving a variety of optimization issues. However, it undergoes weak global search capability because of the levy distribution in its optimization process. In this paper, a variant of HHO is proposed using Crisscross Optimization Algorithm (CSO) to compensate for the shortcomings of original HHO. The novel developed optimizer called Crisscross Harris Hawks Optimizer (CCHHO), which can effectively achieve high-quality solutions with accelerated convergence on a variety of optimization tasks. In the proposed algorithm, the vertical crossover strategy of CSO is used for adjusting the exploitative ability adaptively to alleviate the local optimum; the horizontal crossover strategy of CSO is considered as an operator for boosting explorative trend; and the competitive operator is adopted to accelerate the convergence rate. The effectiveness of the proposed optimizer is evaluated using 4 kinds of benchmark functions, 3 constrained engineering optimization issues and feature selection problems on 13 datasets from the UCI repository. Comparing with nine conventional intelligence algorithms and 9 state-of-the-art algorithms, the statistical results reveal that the proposed CCHHO is significantly more effective than HHO, CSO, CCNMHHO and other competitors, and its advantage is not influenced by the increase of problems' dimensions. Additionally, experimental results also illustrate that the proposed CCHHO outperforms some existing optimizers in working out engineering design optimization; for feature selection problems, it is superior to other feature selection methods including CCNMHHO in terms of fitness, error rate and length of selected features.Supplementary informationThe online version contains supplementary material available at 10.1007/s42235-022-00298-7.