Visualization System for Earth Environmental Data Base

Ikoma, Eiji,Kitsuregawa, Masaru 대한원격탐사학회 1998 International Symposium on Remote Sensing Vol.14 No.1

The earth's environmental problems have attracted serious attention worldwide. Various kinds of environmental data, such as remote sensing data, have become available for examining. Although this data is crucial to understanding such problems, there has become an over-abundance in variety of size, format, and filetype which makes it difficult for researchers to handle. We feel that earth environmental researchers should not be burdened by such cumbersome tasks. Therefore, we are developing a digital library for earth environmental information and a VRML based data visualization system for it. Even now, content-based image retrieval systems have many problems attributed to the degree of difficulty in implementing them. Thus, we are trying to visualize this data so that researchers can utilize it more efficiently, effectively, and easily. A great advantage for VRML users is that people can see environmental data from any perspective above the earth and with any resolution easily. Also by using MPEG-movie, users can observe the changes of data drawn from time series files.

A satellite image database featuring WWW

Ikoma, Eiji,Takagi, Mikio 대한원격탐사학회 1996 International Symposium on Remote Sensing Vol.12 No.1

Recent attention to global environmental changes has stimulated the development of large scale global information systems. Satellite images play a very important role in understanding these global changes. However, there is no suitable and available database system for them. Moreover, WWW(World Wide Web) becomes very popular and many researchers get the environment of use it in these days. It is easy to use, no need to buy special software or hardware, and has more some advantages. This paper describes satellite image database system configurations featuring WWW and its contents.

Lack of an Apparent Association between Mycotoxin Concentrations in Red Chili Peppers and Incidence of Gallbladder Cancer in India : an Ecological Study

Ikoma, Toshikazu,Kapoor, Vinay Kumar,Behari, Anu,Mishra, Kumudesh,Tsuchiya, Yasuo,Asai, Takao,Endoh, Kazuo,Okano, Kiyoshi,Nakamura, Kazutoshi Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.7

Our recent studies conducted in South America have shown that mycotoxin contamination of red chili peppers (RCPs) may be associated with an increased risk of gallbladder cancer (GBC). Whether this relationship exists in India, a country with a high incidence of GBC and high consumption of RCPs, is unclear. We therefore measured concentrations of aflatoxins (AFs) and ochratoxin A (OTA) in RCPs from areas of low, medium, and high incidence of GBC in India, and compared these concentrations with GBC incidence in each area. Twenty-one RCP samples were collected from nine cities (eight from a low-incidence area, five from a medium-incidence area, and eight from a high-incidence area). Concentrations of AFs and OTA were measured using high-performance liquid chromatography. No significant differences in mean concentrations of AFs and OTA were found in the three areas. AFB1 levels in the low-incidence area ($10.81{\mu}g/kg$) and high-incidence area ($12.00{\mu}g/kg$) were more than 2.2 and 2.4 times higher compared with the maximum permitted level of AFB1 in spices ($5.0{\mu}g/kg$) set by the Commission of the European Communities, or that ($4.4{\mu}g/kg$) obtained in our previous study in Chile. Our results show that the mean concentrations of mycotoxins in RCPs are similar among the three areas in India with different incidences of GBC. Further studies with human subjects are needed to evaluate any association between AFB1 and GBC.

Ochratoxin A Contamination of Red Chili Peppers from Chile, Bolivia and Peru, Countries with a High Incidence of Gallbladder Cancer

Ikoma, Toshikazu,Tsuchiya, Yasuo,Asai, Takao,Okano, Kiyoshi,Ito, Naoko,Endoh, Kazuo,Yamamoto, Masaharu,Nakamura, Kazutoshi Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.14

Our previous study detected aflatoxins in red chili peppers from Chile, Bolivia, and Peru, each of which have a high incidence of gallbladder cancer (GBC). Since the aflatoxin B1 concentration was not so high in these peppers, it is important to clarify the presence of other mycotoxins. Here we attempted to determine any associations between the concentrations of aflatoxins and ochratoxin A (OTA) in red chili peppers, and the corresponding GBC incidences. We collected red chili peppers from three areas in Peru: Trujillo (a high GBC incidence area), Cusco (an intermediate GBC incidence area), and Lima (a low GBC incidence rate), and from Chile and Bolivia. Aflatoxins and OTA were extracted with organic solvents. The concentrations of aflatoxins B1, B2, G1, and G2, and OTA were measured by high-performance liquid chromatography. The values obtained were compared with the incidence of GBC in each area or country. All of the red chili peppers from the three areas showed contamination with aflatoxins below the Commission of the European Communities (EC) recommended limits ($5{\mu}g/kg$), but the OTA contamination of two samples was above the EC recommended limit ($15{\mu}g/kg$). The mean concentrations of OTA in the peppers from Chile (mean $355{\mu}g/kg$, range < $5-1,059{\mu}g/kg$) and Bolivia (mean $207{\mu}g/kg$, range $0.8-628{\mu}g/kg$), which has a high incidence of GBC, were higher than that in Peru ($14{\mu}g/kg$, range < $5-47{\mu}g/kg$), which has an intermediate GBC incidence. The OTA contamination in the red chili peppers from Chile, Bolivia, and Peru was stronger than that of aflatoxins. Our data suggest that OTA in red chili peppers may be associated with the development of GBC.

Tracking of 3D Sound Source Location by Particle Filter with TDOA and Signal Power Ratio

Norikazu Ikoma,Osamu Tokunaga,Hideaki Kawano,Hiroshi Maeda 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

A new sound source tracking method in 3 dimensional space using state space modeling approach and particle filter as a state estimation method has been proposed. Not only TDOA (Time Difference Of Arrival) as our previous works including by the authors, but also using power ratio of two sound signals from microphone pair are effectively used in formulation of state space model. Simulational experiments consisting of 1) fundamental tracking with four microphones and 2) human head tracking in car cabin have been conducted with efficient performance in SNR 20dB environment with about 3,000 number of particles.

Elucidation of rapid reduction of water flow through concrete crack regarded as self-healing phenomenon

Hayato Ikoma 한양대학교 세라믹연구소 2015 Journal of Ceramic Processing Research Vol.16 No.S1

The development of self-healing concrete has witnessed several strides in the last three decades. Among these is the understanding of the mechanisms of self-healing concrete, as well as the realization of new technologies of enhancing crack self-healing in concrete. Previous research suggests that crack closing mechanism occurs due to mainly 1) Hydration of anhydrous cement, 2) Formation and crystallization of Calcium Carbonate, 3) Swelling of cement matrix and 4) Sedimentation of particles in the crack interstices. In this research however, after investigating them one by one it was found that these mechanisms do not explain the drastic water flow recovery that occurs in the early stages of water permeation through cracked concrete. It then prompted direct visual observation of water flow through crack narrow space; and with this an interesting finding was observed-the air bubble effect. It was observed that water flow through the narrow crack openings creates air bubbles by various water action mechanisms. The created air bubbles narrow water flow paths in the crack causing significant water flow reduction in the initial and later stages of water supply condition.

Neural sensitization caused by skin inflammation

Akihiko Ikoma 한국피부장벽학회 2009 한국피부장벽학회지 Vol.11 No.2

Itch is a common symptom accompanying many skin diseases and decreases the quality of life. Most of itch is, however, difficult to be treated by therapeutic options available nowadays. Although the identification of the itch-specific neural pathway was a breakthrough in itch research, it was not enough to solve the lack of therapeutic methods. On the other hand, research works on pain mechanisms have been showing that neural sensitization plays an important role in diseases with chronic diseases. Our group has been demonstrating similar phenomena, which are presumably caused by neural sensitization, in skin diseases with chronic pruritus. Patients with atopic dermatitis, for instance, feel itchy by stimuli that are normally not itchy. Moreover, stimuli that are normally painful and inhibit itch can induce itch in patients with atopic dermatitis. Previous studies on pain sensitization have revealed that prostanoids, neurotrophic factors and other inflammatory mediators can sensitize neural receptors, i.e. lower their threshold and cause action potential to arise more frequently. On the other hand, central neural mechanism is likely to be involved in neural sensitization, too, because itch and pain sensitization can occur without skin inflammation. Neural sensitization must always be considered in therapies for itchy diseases and can be the target of drug development for itch.

Protease-Activated Receptors-2: Role in Skin Biology and Barrier Function

Ferda Cevikbas,Akihiko Ikoma,Martin Steinhoff 한국피부장벽학회 2009 한국피부장벽학회지 Vol.11 No.2

Proteinases play an essential role in skin homeostasis and various disease states. This is -at least in part-mediated via activation of proteinase-activated receptors (PARs). These are G-protein-coupled receptors with seven transmembrane domains that are activated by specific proteolytic cleavage of the extracellular N-terminus. To date, four PARs are cloned and characterized (PAR1-4). They are stimulated by a variety of serine proteinases. PAR1, PAR3 and PAR4 are cleaved by thrombin, for example. Both PAR1 and PAR4 can be activated by trypsin as well; PAR4 can be also activated by cathepsin G and PAR1 can also be triggered by matrix metalloproteinase-1. PAR2 can be activated by a variety of endogenous serine proteinases like tryptase, matriptase or certain kallikreins. The latter have an important impact in the regulation of skin barrier and may thus be involved in its malfunction during disease state. This receptor can additionally be stimulated by various exogenous proteinases produced by pathogenic organisms like mites, bacteria or fungi, which are capable of modulating epidermal barrier function. It can also be inactivated by certain proteinases which may be of pathophysiological releavance; these mechanisms, however, are poorly understood as of yet. PAR2 is expressed by many cell types present in the skin including keratinocytes in the higher epidermal layers, fibroblasts, endothelial cells as well as by sensory neurons. Moreover, functional PAR2 is expressed by cells crucially involved in innate and adaptive immunity such as eosinophils, neutrophils, monocytes, macrophages, dendritic cells, mast cells and T cells, which may affect skin barrier function during inflammation and immune responses. Activation of the receptor leads to the production of various cytokines, chemokines or growth factors thereby modulating skin homeostasis, barrier function, immune and inflammatory responses as well as tumor surveillance. Thus, aiming at proteases and PARs may be beneficial for the treatrment of various skin diseases and barrier dysfunction.

A case of hepatic anisakidosis caused by Anisakis pegreffii mimicking liver cancer

Minoru Yamada,Fumi Murakoshi,Hisashi Ikoma,Osamu Inamori,Akio Yanagisawa,Eiichi Konishi 대한기생충학ㆍ열대의학회 2023 The Korean Journal of Parasitology Vol.61 No.3

Extra-gastrointestinal anisakidosis is rare. We herein report an Anisakis pegreffii infection in a patient with hepatic anisakidosis diagnosed based on its molecular identification. A 71-year-old male patient had a hepatic tumor presenting as a low-density area of 20 mm in diameter in segment 6 of the liver on abdominal ultrasonography, computed tomography, and magnetic resonance imaging. The surgically resected pathological specimen revealed a necrotizing eosinophilic granuloma containing nematode larvae, possibly an Anisakis larva. Molecular and phylogenetic analysis demonstrated Anisakis larvae belonging to A. pegreffii. The present results will help identify and characterize unknown Anisakis species in histological sections.

Introduction of Characteristics of Rubber Joiner : Durability and Effect of Impact Load Reduction

Katsumasa Takubuchi,Michiya Miki,Mobuyasu Ikoma,안희도 한국해안해양공학회 1996 학술강연회 발표논문초록집 Vol.1 No.1