Masaki Yasugi

Utsunomiya University

The left-right asymmetry of scale-eating Tanganyikan cichlids is described as a unilateral topographical shift of the quadratomandibular joints. This morphological laterality has a genetic basis and has therefore been used as a model for studying negative frequency-dependent selection and the resulting oscillation in frequencies of two genotypes, l...

Vertebrates show left-right biases in turning direction, limb usage, predator-escape response and use of sensory organs. In particular, some fishes are known to have lateral biases in predatory behaviors corresponding to their morphological antisymmetry. To reveal the effects of these laterally biased behaviors on predator-prey interaction, we cond...

Asymmetry in animal bodies and behavior has evolved several times, but our knowledge of their linkage is limited. Tanganyikan scale-eating cichlids have well-known antisymmetry in their bodies and behavior; individuals open their mouths leftward (righty) or rightward (lefty), and righties always attack the right flank of the prey, whereas lefties a...

The predator-prey relationship between largemouth bass, Micropterus salmoides, and freshwater goby, Rhinogobius spp., in Lake Biwa, Japan, was examined with respect to their morphological antisymmetry (laterality). Largemouth bass and Rhinogobius gobies exhibited lateral dimorphism in the height of the mandible and the length of the dentary, respec...

Interspecific variation in diel-scale temporal niches is common in natural communities. Such variation changes population dynamics via effects on the growth and reproduction of individuals. Also at the community level, theory predicts that animals can reduce competition for shared resources by changing diel activity in certain situations. However,...

This paper proposes a method to improve the modulation transfer function (MTF) of aerial images by combining an aerial imaging optical system by retro-reflection with conjugated two transparent spheres. In the proposed optical system, the transparent spheres collimate the light incident on the retro-reflector to improve the resolution by making the...

We propose a pre-processing method of source image to reduce blur of aerial image that is formed with aerial imaging by retro-reflection (AIRR). In the AIRR optical system, anisotropic blurring occurs due to the influence of diffraction on the surface of the optical element. In this experiment, we measured the point spread function with multiple re...

We propose multiple aerial imaging system by use of two beam splitters in the optical system of aerial imaging by retro-reflection (AIRR). The AIRR optical system consists of a light source, a beam splitter, and a retro-reflector. Use of two-layered beam splitters enables us to show multiple aerial signs to drivers in multiple driving lanes. The pu...

By combining an aerial display, user tracking system, and virtual reality (VR) space, we realized an aerial interface for providing both an immersive user experience and real-time communication with people outside the device. We developed a simple application for detecting user contact and changing the color of an object to measure the latency of o...

Predator-prey interactions based on laterality have recently been observed between fishes and their prey populations. Maintenance of antisymmetric dimorphism by frequency-dependent selection has been reported in fish, but has not been observed in invertebrates. Over 10 years, we investigated long-term changes in the "ratio of laterality" (frequency...

We propose a method to realize video calling with an aerial display using a camera that has a direct view of the speaker's face, but which is not visible to the speaker. Because the aerial display uses p-AIRR (polarization-modulated aerial imaging by retro-reflection), we show that it is possible to take advantage of the polarization encoding of th...

This chapter describes the effects of morphological antisymmetry and behavioral lateralization on predator-prey interactions in fishes. In fishes with morphological antisymmetry, predation events are defined as either cross-predation (the predator takes in prey of a different morphological type to itself) or parallel-predation (the predator takes i...

The water flea, Daphnia magna, is a representative zooplankton that lives in freshwater environments. It primarily propagates via asexual reproduction in normal and healthy environmental conditions. Unsuitable environmental conditions induce D. magna to change its mode of reproduction from asexual to sexual reproduction. During sexual reproduction,...

This paper evaluates the spatial distortion of aerial image and proposes a novel optical design to utilize the distortion as visual expression. Our optical system is based on aerial imaging by retro-reflection (AIRR). Using acrylic plate as beam splitter, a clear aerial image can be obtained at low cost. However, when upsizing the device, there is...

AIRR (Aerial imaging by retro-reflection) can form a large aerial image in mid-air for digital signage. Resolution of the aerial image formed with AIRR is determined mainly by the retro-reflector, which is one of its components. However, increasing the resolution of aerial images by increasing the density of retro-reflective elements poses physical...

This paper proposes a novel steganography method to show an aerial image that is formed with aerial imaging by retro-reflection by use of dual transparent balls made of acrylic resin. Our optical system forms a floating image screen in front of an acrylic ball that is placed on a beam splitter. We have confirmed our proposed optical system by perfo...

Since ancient times, humans have bred several plants that we rely on today. However, little is known about the divergence of most of these plants. In the present study, we investigated the divergence of Mibuna (Brassica rapa L. subsp. nipposinica L. H. Bailey), a traditional leafy vegetable in Kyoto (Japan), by combining genetic analysis and a surv...

We have utilized single-pixel imaging and deep-learning to solve the privacy-preserving problem in gesture recognition for interactive display. Silhouette images of hand gestures were acquired by use of a display panel as an illumination. Reconstructions of gesture images have been performed by numerical experiments on single-pixel imaging by chang...

We have realized a novel optical system to form a large aerial image in front of a full-color LED panel that is covered with retro-reflector. The retro-reflector has square apertures through which lights from the LED pixels pass. Our optical system is based on aerial imaging by retro-reflection (AIRR). The aerial image formed with AIRR is visible o...

A Japanese piscivorous chub, "hasu" (Opsariichthys uncirostris), and its main prey, "ayu" (Plecoglossus altivelis), both have laterally asymmetric bodies, similar to other fishes; each population consists of righty morphs and lefty morphs. This antisymmetric dimorphism has a genetic basis. Temporal changes in the ratios of laterality (i.e., frequen...

This paper proposes a novel optical system to form an aerial image over a transparent sphere. The proposed optical system is composed of two transparent acrylic spheres in the light path of the aerial imaging by retro-reflection (AIRR) device. The first sphere collects the diverging light rays from a light-source display. The second sphere converge...

The water flea Daphnia magna is a representative example of zooplankton living in freshwater environments. They primarily propagate via asexual reproduction under normal and healthy environmental conditions. Environmental stimuli that signal a shift to disadvantageous conditions induce D. magna to change their mode of reproduction from asexual to s...

To realize a triple-views aerial image floating in the center of the passages that can be displayed in front of an user and passed through, we propose a novel display device using aerial imaging with retro-reflection with polarization. We confirmed that our device can form aerial images in the center of the intersection of three passages and can di...

The genetic bases of growth and body weight are of economic and scientific interest, and teleost fish models have proven useful in such investigations. The Oryzias latipes species complex (medaka) is an abundant freshwater fish in Japan and suitable for genetic studies. We compared two wild medaka stocks originating from different latitudes. The Ma...

A c c e p t e d M a n u s c r i p t 2  Background and Aims The genus Asarum sect. Heterotropa (Aristolochiaceae) likely experienced rapid diversification into 62 species centred on the Japanese Archipelago and Taiwan, providing an ideal model for studying island adaptive radiation. However, resolving the phylogeny of this plant group using Sanger...

Background and aims: The genus Asarum sect. Heterotropa (Aristolochiaceae) likely experienced rapid diversification into 62 species centred on the Japanese Archipelago and Taiwan, providing an ideal model for studying island adaptive radiation. However, resolving the phylogeny of this plant group using Sanger sequencing-based approaches has been c...

Background and aims: Contrasting life-history traits can evolve through generations of dwarf plant ecotypes, yet such phenotypic changes often involve decreased plant size and reproductive allocation, which can configure seed dispersal patterns and, subsequently, population demography. Therefore, evolutionary transitions to dwarfism can represent...

To study the genetic structure of clonal plant populations, genotyping and genet detection using genetic markers are necessary to assign ramets to corresponding genets. Assignment is difficult as it involves setting a robust threshold of genetic distance for genet distinction as neighbouring genets in a plant population are often genetically relate...

We have realized an omnidirectional aerial display for behavioral experiments. The omnidirectional aerial image is formed using a beam splitter with a cone shape. When an aerial image is shown to medaka and betta fish, they react following the aerial image. Furthermore, we propose a method for changing the position of the aerial image by increasing...

Key message A putative ketoacyl-ACP reductase (CaKR1) that was not previously known to be associated with pungency of Capsicum was identified from map-based cloning and functional characterization. Abstract The pungency of chili pepper fruits is due to the presence of capsaicinoids, which are synthesized through the convergence of the phenylpropan...

In this paper, the image photographed by the light field camera is reconstructed by the light field display, and projected in the air by Fresnel lens and an aerial imaging by retro-reflection (AIRR) technique. This allows you to face the 3D aerial image of the user in another location and perform a realistic conversation.

Objective: Selective breeding for desirable traits is becoming popular in aquaculture. In Miyagi prefecture, Japan, a selectively bred population of Coho salmon (Oncorhynchus kisutch) has been established with the original, randomly breeding population maintained separately. Since they have been bred without family records, the genetic diversity w...

This paper proposes a novel optical system to show an aerial 3D image for a user in front of the display and to show its 2D image for the surrounding viewers. Our optics forms two-layered aerial images that are visible in a limited viewing area. Outside the viewing area, only the rear aerial 2D image is visible. The viewing area is controlled by th...

Stacksbinder (available at https://ps.agr.ryukoku.ac.jp/stacksbinder/) is a web-based tool for summarizing the output of software Stacks, which is widely used to analyze restriction site-associated DNA sequencing (RAD-Seq) data. Although summarization is an essential step in RAD-Seq analysis, no specific tools exist for summarizing and visualizing...

The cerebral cortex predicts visual motion to adapt human behavior to surrounding objects moving in real time. Although the underlying mechanisms are still unknown, predictive coding is one of the leading theories. Predictive coding assumes that the brain's internal models (which are acquired through learning) predict the visual world at all times...

Understanding how genetic variation within a foundation species determines the structure of associated communities and ecosystem processes has been an emerging frontier in ecology. Previous studies in common gardens identified close links between intraspecific variation and multispecies community structure, and these findings are now being evaluate...

Background and Aims The processes and mechanisms underlying lineage diversification are major topics in evolutionary biology. Eurasian goldenrod species of the Solidago virgaurea complex show remarkable morphological and ecological diversity in the Japanese Archipelago, with ecotypic taxa well adapted to specific environments (climate, edaphic cond...

Aerial imaging by retro-reflection (AIRR) is a method to form an aerial image by use of a retro-reflector [1].

Brassica rapa show a wide range of morphological variations. In particular, the leaf morphologies of the Japanese traditional leafy vegetables Mizuna and Mibuna (Brassica rapa L. subsp. nipposinica L. H. Bailey) are distinctly different, even though they are closely related cultivars that are easy to cross. In addition to the differences in the gro...

To cope with seasonal changes in the environment, organisms adapt their physiology and behavior. Although color perception varies among seasons, the underlying molecular basis and its physiological significance remain unclear. Here we show that dynamic plasticity in phototransduction regulates seasonal changes in color perception in medaka fish. Me...

Understanding the genetic bases of local adaptation in dominant conifer species is critical in predicting the impacts of rapid climate change on forest ecosystems. However, the genetic basis of adaptation is not yet fully understood due to the huge and complex genomes of conifers and the unavailability to date of suitable crossing material. In this...

Early stages of ecological speciation can create populations with an ecology and reproduction timing distinct from those of related populations. Landscape genetic models incorporating environmental heterogeneity and population-specific reproductive traits enable the processes of population genetic differentiation to be inferred. We investigated gen...

Laterality has been studied in several vertebrates, mainly in terms of brain lateralization and behavioral laterality, but morphological asymmetry has not been extensively investigated. Asymmetry in fishes was first described in scale-eating cichlids from Lake Tanganyika, in the form of bilateral dimorphism in which some individuals, when opening t...

We studied social approach behaviour in medaka fish using three-dimensional computer graphic (3DCG) animations based on the morphological features and motion characteristics obtained from real fish. This is the first study which used 3DCG animations and examined the relative effects of morphological and motion cues on social approach behaviour in m...

Sample movie of normal virtual medaka (Normal group). The original movie was presented in the lower right corner. (MOV)

Sample movies which were used in experiment 2. There were the following groups: Grey scale/No locomotion, Grey scale/No body motion, Pressed/Grey scale, Pressed/No locomotion, and Pressed/No body motion. (MOV)

Sample movies which were used in experiment 3. There were the following groups: Pressed, Grey scale, No locomotion, and No body motion. (MOV)

Ipomoea is the largest genus in the family Convolvulaceae. Ipomoea nil (Japanese morning glory) has been utilized as a model plant to study the genetic basis of floricultural traits, with over 1,500 mutant lines. In the present study, we have utilized second- and third-generation-sequencing platforms, and have reported a draft genome of I. nil with...

Several studies in the last 20 years have revealed that morphological asymmetry in fish can be characterized as 'antisymmetry'. Antisymmetry is a lateral dimorphism in which each population consists of individuals with well-developed left sides (lefties) and well-developed right sides (righties). This dimorphism influences predator-prey interaction...

White cypress pine (Callitris glaucophylla) is a drought-tolerant evergreen conifer, which is a member of the Australian C. columellaris species complex. The complex is comprised of five closely related morphospecies that occur in a wide range of bioclimatic regions in Australia. Ecological genomics of the complex provides an opportunity to identif...

Scale-eating fishes in freshwater and marine habitats. (DOC)

Scale eating behavior by Exodon paradoxus. This individual was righty in jaw morphology and attacked the left flank of the prey gold fish. (WMV)