歯の発生における新規basic-helix-loop-helix転写因子AmeloDの機能解明

Tohoku University福本敏課

Evidence of introgressive hybridization between the morphologically divergent land snails Ainohelix and Ezohelix

Hybridization between different taxa is likely to take place when adaptive morphological differences evolve more rapidly than reproductive isolation. When studying the phylogenetic relationship between two land snails of different nominal genera, Ainohelix editha and Ezohelix gainesi, from Hokkaido, Japan, using nuclear internal transcribed spacer and mitochondrial 16S ribosomal DNA, we found a marked incongruence in the topology between nuclear and mitochondrial phylogenies. Furthermore, no clear association was found between shell morphology (which defines the taxonomy) and nuclear or mitochondrial trees and morphology of reproductive system. These patterns are most likely explained by historical introgressive hybridization between A. editha and E. gainesi. Because the shell morphologies of the two species are quite distinct, even when they coexist, the implication is that natural selection is able to maintain (or has recreated) distinct morphologies in the face of gene flow. Future studies may be able to reveal the regions of the genome that maintain the morphological differences between these species

Automated Evaluation of Coordinated Movement of Fingers Using Home Rehabilitation Device

Home rehabilitation is much in need in ageing societies. Especially, for hemiplegia patients who have paralysis at fingers, it is known that long continuous rehabilitation is effective for recovery. To automate home rehabilitation without the help of a medical specialist, it is desirable not only to provide a rehabilitation procedure but also to give the condition of the paralysis of the patient. In our previous studies, we proposed a robotic device to foster separative voluntary finger lift movement. The device mounts pressure sensors at each finger to monitor the degree of unwanted finger movements. However, it is not clear which is an effective way to measure the condition of paralysis by these finger pressure time series data. In this paper, we propose a new measurement method that is based on the “coordinated movement” of fingers. A patient is asked to perform 4 tasks: pinch2 (pinch movement by index finger and thumb), pinch3 (pinch movement by index, middle and thumb), grasp2 (grasp movement by the ring and little finger), and grasp3 (grasp movement by the middle, ring, and little finger). All pressure time series of finger movements are quantified their dissimilarities with data of standard healthy subjects. We found that the grasp3 has the largest correspondence relation with the degree of paralysis

Evaluation of Forearm Musclar Function of Hemiplegic Patients Using Displacement MMG

To realise an automated self-rehabilitation at home, it is necessary to provide proper feedback on the status of the recovery of the patient. In a simple finger rehabilitation, a fingertip force monitor is used to detect undesired and paralyzed movement, which is used to determine the degree of recovery. In contrast to the fingertip force, the balance of flexion and extension of finger muscles is another essential feature of the paralysis. However, simultaneous monitoring of flexor and extensor is impossible by using a single fingertip pressure sensor. Usually, EMG is used to monitor individual muscular activity. However, inexperienced home user will not be able to deal with electrodes properly. In this paper, we propose a device to monitor flexion and extension by a unit which is easy to handle. Also, we propose a method to derive a degree of recovery using the signals collected from this device. The results by data collected from healthy and stroke patients show the potential effectiveness of our method

La Cultura de Obsidiana en Teotihuacan Contemporáneo: Producción artesanal como un recurso turístico

要旨（スペイン語）のみ公

CHANGES IN ANGULAR MOMENTUM DURING 10,000 M RACES

INTRODUCTION: In distance running, many coaches and runners pay attention not only to leg motion but also to arm and trunk motion. Hinrich (1987) studied angular momentum in running and suggested that main role of arm and trunk motion in running was to maintain the balance about vertical axis against leg motion. Unfortunately, there was little biomechanical study about arm and trunk motion for elite distance runners in races. The purpose of this study was to investigate the angular momentum about vertical axis for elite distance runners in the 10000m races

Neural Structure Fields with Application to Crystal Structure Autoencoders

Representing crystal structures of materials to facilitate determining them via neural networks is crucial for enabling machine-learning applications involving crystal structure estimation. Among these applications, the inverse design of materials can contribute to next-generation methods that explore materials with desired properties without relying on luck or serendipity. We propose neural structure fields (NeSF) as an accurate and practical approach for representing crystal structures using neural networks. Inspired by the concepts of vector fields in physics and implicit neural representations in computer vision, the proposed NeSF considers a crystal structure as a continuous field rather than as a discrete set of atoms. Unlike existing grid-based discretized spatial representations, the NeSF overcomes the tradeoff between spatial resolution and computational complexity and can represent any crystal structure. To evaluate the NeSF, we propose an autoencoder of crystal structures that can recover various crystal structures, such as those of perovskite structure materials and cuprate superconductors. Extensive quantitative results demonstrate the superior performance of the NeSF compared with the existing grid-based approach.Comment: 16 pages , 6 figures. 13 pages Supplementary Informatio

Sox21 Regulates Anapc10 Expression and Determines the Fate of Ectodermal Organ

The transcription factor Sox21 is expressed in the epithelium of developing teeth. The present study aimed to determine the role of Sox21 in tooth development. We found that disruption of Sox21 caused severe enamel hypoplasia, regional osteoporosis, and ectopic hair formation in the gingiva in Sox21 knockout incisors. Differentiation markers were lost in ameloblasts, which formed hair follicles expressing hair keratins. Molecular analysis and chromatin immunoprecipitation sequencing indicated that Sox21 regulated Anapc10, which recognizes substrates for ubiquitination-mediated degradation, and determined dental-epithelial versus hair follicle cell fate. Disruption of either Sox21 or Anapc10 induced Smad3 expression, accelerated TGF-beta 1-induced promotion of epithelial-to-mesenchymal transition (EMT), and resulted in E-cadherin degradation via Skp2. We conclude that Sox21 disruption in the dental epithelium leads to the formation of a unique microenvironment promoting hair formation and that Sox21 controls dental epithelial differentiation and enamel formation by inhibiting EMT via Anapc10.Peer reviewe