A computational framework for canonical holistic morphometric analysis of trabecular bone

Bone is a remarkable, living tissue that functionally adapts to external loading. Therefore, bone shape and internal structure carry information relevant to many disciplines, including medicine, forensic science, and anthropology. However, morphometric comparisons of homologous regions across different individuals or groups are still challenging. In this study, two methods were combined to quantify such differences: (1) Holistic morphometric analysis (HMA) was used to quantify morphometric values in each bone, (2) which could then be mapped to a volumetric mesh of a canonical bone created by a statistical free-form deformation model (SDM). Required parameters for this canonical holistic morphometric analysis (cHMA) method were identified and the robustness of the method was evaluated. The robustness studies showed that the SDM converged after one to two iterations, had only a marginal bias towards the chosen starting image, and could handle large shape differences seen in bones of different species. Case studies were performed on metacarpal bones and proximal femora of different primate species to confirm prior study results. The differences between species could be visualised and statistically analysed in both case studies. cHMA provides a framework for performing quantitative comparisons of different morphometric quantities across individuals or groups. These comparisons facilitate investigation of the relationship between spatial morphometric variations and function or pathology, or both

The deep trabecular structure of first metacarpals in extant hominids

Objectives: Recent studies have associated subarticular trabecular bone distribution in the extant hominid first metacarpal (Mc1) with observed thumb use, to infer fossil hominin thumb use. Here, we analyze the entire Mc1 to test for interspecific differencesin: (1) the absolute volume of trabecular volume fraction, (2) the distribution ofthe deeper trabecular network, and (3) the distribution of trabeculae in the medullarycavity, especially beneath the Mc1 disto-radial flange. Materials and Methods: Trabecular bone was imaged using micro-computed tomography in a sample of Homo sapiens (n = 11), Pan paniscus (n = 10), Pan troglodytes(n = 11), Gorilla gorilla (n = 10) and Pongo sp., (n = 7). Using Canonical Holistic Morphometric Analysis (cHMA), we tested for interspecific differences in the trabecular bone volume fraction (BV/TV) and its relative distribution (rBV/TV) throughout the Mc1, including within the head, medullary cavity, and base. Results: P. paniscus had the highest, and H. sapiens the lowest, BV/TV relative to other species. rBV/TV distribution statistically distinguished the radial concentrations and lack of medullary trabecular bone in the H. sapiens Mc1 from all other hominids. H. sapiens and, to a lesser extent, G. gorilla also had a significantly higher trabecular volume beneath the disto-radial flange relative to other hominids. Discussion: These results are consistent with differences in observed thumb use in these species and may also reflect systemic differences in bone volume fraction. The trabecular bone extension into the medullary cavity and concentrations beneath the disto-radial flange may represent crucial biomechanical signals that will aid in the inference of fossil hominin thumb use

Evaluation of Modular Power Converter Integrated with 5G Network

This paper focuses on two key technical concepts, which may have a tremendous impact on future generations of power electronic converters: the Power Electronic Building Block (PEBB) concept, and the 5G/6G wireless data transfer. It is expected that these two trends may induce development of new cognitive of power electronic converters: Power Electronics 4.0. To investigate this concept, a Proof of Concept (PoC) of PEBB-based power converter integrated with a 5G network, was designed and tested. Study confirmed that power converter assembled from PEBB modules can compete with state-of-the-art devices. Moreover, test results indicates that several challenges related to PEBB and integration of power electronic equipment with 5G network has to be resolved, to enable growth of augmented power electronic converters, especially if wireless data transfer is meant for communication between PEBB modules

WBG-Based PEBB Module for High Reliability Power Converters

The increasing presence of power electronic converters in the modern world – from electric vehicles, up to industrial applications – brings up concerns about their reliability, especially in the case of the Wide Band-Gap (WBG) devices. Moreover, ensuring high reliability becomes more challenging due to constantly increasing focus on the development of new types of power supplies in a shorter time. Thus, research over reliability improvement of modern power converters was initiated. In this paper, a concept of Design For Reliability (DfR) procedure, suitable for projects with a short lifespan, and a case study of Power Electronic Building Block (PEBB) designed according to the proposed procedure are presented. Furthermore, a Reliability Oriented Control (ROC) algorithm for WBG-based converters is discussed

Single Amino Acid Substitution in Aquaporin 11 Causes Renal Failure

A screen of recessive mutations generated by the chemical mutagen n-ethyl-n-nitrosourea (ENU) mapped a new mutant locus (5772SB) termed sudden juvenile death syndrome (sjds) to chromosome 7 in mice. These mutant mice, which exhibit severe proximal tubule injury and formation of giant vacuoles in the renal cortex, die from renal failure, a phenotype that resembles aquaporin 11 (Aqp11) knockout mice. In this report, the ENU-induced single-nucleotide variant (sjds mutation) is identified. To determine whether this variant, which causes an amino acid substitution (Cys227Ser) in the predicted E-loop region of aquaporin 11, is responsible for the sjds lethal renal phenotype, Aqp11−/sjds compound heterozygous mice were generated from Aqp11+/sjds and Aqp11+/− intercrosses. The compound heterozygous Aqp11−/sjds offspring exhibited a lethal renal phenotype (renal failure by 2 wk), similar to the Aqp11sjds/sjds and Aqp11−/− phenotypes. These results demonstrate that the identified mutation causes renal failure in Aqp11sjds/sjds mutant mice, providing a model for better understanding of the structure and function of aquaporin 11 in renal physiology