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Yamaguchi N.,Japan National Institute for Agro - Environmental Sciences | Mori S.,Japan National Institute for Agro - Environmental Sciences | Mori S.,Japan National Agriculture and Food Research Organization | Baba K.,Japan National Institute for Agro - Environmental Sciences | And 6 more authors.
Environmental and Experimental Botany | Year: 2011

Root-to-shoot cadmium (Cd) translocation in Solanum torvum is lower than that of the eggplant Solanum melongena; therefore, grafting S. melongena onto S. torvum rootstock can effectively reduce the Cd concentration in eggplant fruits. We hypothesized that Cd transport in S. torvum roots is restricted in the path between the epidermis and xylem vessel; hence, we investigated the Cd distribution in the roots at the micron-scale. Elemental maps of Cd, Zn and Fe accumulation in S. melongena and S. torvum root sections were obtained by synchrotron micro X-ray fluorescence spectrometry. The Cd was localized in both the stele and the epidermis of the S. melongena root cross sections regardless of the distance from the root apex. In S. torvum root sections taken at 30 and 40. mm above the root apex, a higher abundance of Cd was found within the cells of the endodermis and pericycle. The results suggested that the symplastic uptake and xylem loading of Cd in S. torvum roots were restricted, and thereby, the Cd that was unable to be loaded into the xylem accumulated in the endodermis and in the pericycle. Because symplastic uptake differs only slightly between the two species, the difference in xylem loading would explain the comparatively lower Cd concentration in S. torvum shoots. © 2010 Elsevier B.V.


Sakai Y.,Hokkaido University | Sakai Y.,Fujita Co. | Watanabe T.,Hokkaido University | Wasaki J.,Hiroshima University | And 3 more authors.
Environmental Pollution | Year: 2010

The roles of low-molecular-weight thiols (LMWTs), such as glutathione and phytochelatins, in arsenic (As) tolerance and hyperaccumulation in Pteris vittata an As-hyperaccumulator fern remain to be better understood. This study aimed to thoroughly characterize LMWT synthesis in P. vittata to understand the roles played by LMWTs in As tolerance and hyperaccumulation. LMWT synthesis in P. vittata was induced directly by As, and not by As-mediated oxidative stress. Expression of PvECS2, one of the putative genes of γ-glutamylcysteine synthetase (γECS), increases in P. vittata shoots at 48 h after the onset of As exposure, almost corresponding to the increase in the concentrations of γ-glutamylcysteine and glutathione. Furthermore, localization of As showed similar trends to those of LMWTs in fronds at both whole-frond and cellular levels. This study thus indicates the specific contribution of LMWTs to As tolerance in P. vittata. γECS may be responsible for the As-induced enhancement of LMWT synthesis. © 2010 Published by Elsevier Ltd. All rights reserved.


Nakazawa T.,Fujita Corporation | Masuda K.,Fujita Corporation | Kondoh T.,Daiwa House Industry Co.
IABSE Conference, Nara 2015: Elegance in Structures - Report | Year: 2015

Ill this paper we describe a new system floor vibration analysis using a finite element method which makes it easy for users to input data and visualize results. This system is linear elastic vibration analysis software called "Yurayzer3'\ It comprises a pre-processor unit, a calculation unit and a post-processor unit. The chief innovation of this system is the in-house development of a pre-processor and post-processor that simplifies the numerical inputs of information about nodes and elements. In order to verify the analytical accuracy of this system, the eigenvalue analysis is carried out and compared with measured values. This comparison showed a coefficient of variation about 10%, which is a level of agreement sufficient for the structural design phase.


Kashem M.A.,Iwate University | Singh B.R.,Norwegian University of Life Sciences | Kubota H.,Fujita Corporation | Sugawara R.,Fujita Corporation | And 3 more authors.
Environmental Science and Pollution Research | Year: 2010

Background, aim, and scope: Zinc is an essential micronutrient element but its concentrations found in contaminated soils frequently exceed those required by the plant and soil organisms, and thus create danger to animal and human health. Phytoremediation is a technique, often employed in remediation of contaminated soils, which aims to remove heavy metals or other contaminants from soils or waters using plants. Arabidopsis (A.) halleri ssp. gemmifera is a plant recently found to be grown vigorously in heavy metal contaminated areas of Japan and it contained remarkably high amount of heavy metals in its shoots. However, the magnitude of Zn accumulation and tolerance in A. halleri ssp. gemmifera need to be investigated for its use as a phytoremediation plant. Materials and methods: A. halleri ssp. gemmifera was grown for 3 weeks into half-strength nutrient solution with Zn (as ZnSO4) levels ranging from 0.2 to 2,000 μM. The harvested plants were separated into shoots and roots, dried in the oven, and ground. The plant tissue was digested with nitric-perchloric acid, and the Zn concentration in the digested solution was measured by atomic absorption spectrophotometer. Results and discussion: The results showed no reduction in shoot and root dry weight when plants were grown at 0.2 to 2,000 μM Zn in the solution. The highest Zn concentration measured in the shoots was 26,400 mg kg-1 at 1,000 μM Zn, while in the roots, it was 71,000 mg kg-1 at 2,000 μM Zn treatment. Similar to the Zn concentration in plant parts, maximum Zn accumulation of 62 mg plant-1 in the shoots and 22 mg plant-1 in the roots was obtained at 1,000 and 2,000 μM Zn in the solution. The percentage of Zn translocation in shoot varied from 69% to 90% of the total Zn, indicating that the shoot was the major sink of Zn accumulation in this plant. Conclusions: The results of this study indicate that the growth of A. halleri ssp. gemmifera was not affected by the Zn level of up to 2,000 μM in the nutrient solution. The concentration of Zn found in shoot indicated that A. halleri ssp. gemmifera has an extraordinary ability to tolerate and accumulate Zn and hence a good candidate for the phytoremediation of Zn-polluted soil. Recommendations and outlook: Based on the results presented in this study and earlier hydroponics, and field study, A. halleri ssp. gemmifera seems to be a potential heavy metals hyperaccumulator, and could be recommended to use for phytoremediation of Cd- and Zn-contaminated soils. © 2010 Springer-Verlagkashem00@yahoo.com.


Ono Y.,Fujita Corporation | Ono Y.,Shinshu University | Nakagomi T.,Shinshu University | Kaneko H.,Shinshu University
Journal of Structural and Construction Engineering | Year: 2016

The main object of this study is the scale effect with the destruction of the wood. In the steel, Ji value is a material characteristic value so it does not depend on size. The more the size of specimen is large, the more the stress at Ji is small. So it is easy to make the dangerous judgment of destruction. This property can be found in the wood, we make the JIC test with Japanese larch. As a result, it was seen similar trend as steel to wood, it found that the application of fracture mechanics to the destruction of wood is effective.


Masuda K.,FUJITA Corporation | Nakayama M.,National Institute of Technology,Oyama College | Ogawa T.,Tokyo Institute of Technology
Journal of Environmental Engineering (Japan) | Year: 2016

This paper proposes a reliability based design for limiting floor slab vibration due to human walk. The reliability index β can predict the stochastic vibration performance of any floor slabs, independent of the dynamic characteristics of floor slabs. The reliability design method was applied to an actual floor slab design and its validity was confirmed by hammering tests and a one person walking test using the actual building floor slabs.


Masuda K.,FUJITA Corporation | Nakayama M.,National Institute of Technology,Oyama College | Ogawa T.,Tokyo Institute of Technology
Journal of Environmental Engineering (Japan) | Year: 2015

This paper proposes the walking vibration V-value response spectrum as an evaluation method of the habitability index V-value derived from a Monte-Carlo simulation and shows verifications with actual walking tests. The following conclusions were obtained. 1 Monte-Carlo simulations using stochastic walking force model were carried out. The effects of each parameter were clarified, such as the natural frequency, damping coefficient, and the effective mass of the floor slab, the number of people walking, their average body weight, average pacing rate, and the variation of pacing rate of the people walking, and the walking distance. 2 The mean values and variation coefficients of V-value are expressed by the natural frequency, the effective mass, the damping coefficient of the floor slab, the average weight per walker and the number of people walking. Based on these functions, the walking vibration V-value response spectrum is proposed. 3 The Proposed V-value response spectrums were verified by actual walking tests on seven floor slabs.


Masuda K.,Fujita Corporation | Nakayama M.,National Institute of Technology,Oyama College | Ogawa T.,Tokyo Institute of Technology
INTER-NOISE 2015 - 44th International Congress and Exposition on Noise Control Engineering | Year: 2015

This paper estimates the vibration of floor slabs caused by people walking stochastically. Estimating the habitability index based on floor slab vibration due to human activity is important in designing steel structure buildings such as offices, shopping malls etc. But since the variation of this vibration can be large, its calculation can be difficult. This study attempts to evaluate floor slab vibration due to humans walking stochastically. Initially, full-scale measurements were carried out to determine the characteristics of vibration on a structure due to human walking. One or more people walked along a simply supported pedestrian corridor connecting two buildings in order to determine the statistics of Vvalues. The V-value is a 1/3 octave band peak spectrum of response accelerations corrected based on human perception. The distribution of the response V-values followed a lognormal distribution, with average values proportionate to the square root of the number of people walking, and variation coefficients reducing gradually as the number of people increased. In addition numerical simulations were carried out using the Monte-Carlo method with an improved, extended stochastic walk force model. It was clearly shown that the experimentally obtained results could successfully reproduced by using the Monte- Carlo simulation developed by authors. © 2015 by ASME.


Ohno R.,Tokyo Institute of Technology | Wada Y.,Fujita Co.
Communications in Computer and Information Science | Year: 2012

When we visit a complex public space such as a railway station or a large shopping mall for the first time, we must rely on guide signs to find our way. In crowded situations, we are called upon to read these signs while walking so as not to disturb pedestrian flow. The present study uses an immersive visual simulation system to examine the influence of observation conditions on sign detection and recognition. The experimental variables address the spatial layout of signs as well as the presence of other pedestrians. The results indicate some quantitative relationships between the above variables and readability and suggest effective layouts for signs in spaces where crowded conditions are unavoidable. © Springer-Verlag Berlin Heidelberg 2012.


Minakawa K.,Fujita Corporation | Iwata S.,Nihon University
AIJ Journal of Technology and Design | Year: 2011

The number of more than thirty-year old condominium is predicted to be increasing drastically. The problem is how the independent renovation of these condominiums in the urban area will be attained. The purpose of this paper is to evaluate the reconstruction-feasibility of old condominiums by reducing the rate which is calculated from "land price based on street value" and "construction cost". By using the evaluation model based on the equivalent exchange, the characteristics of Bunkyo and Koto ward of Tokyo on the reconstruction-feasibility are clearly confirmed. The simulation has been conducted on cases of mixing "a self-pay burden for residents", "alteration in the unit area", and "the diminishing the ratio of the total floor area." With time series analysis, the effects of reducing self-pay expense for each area and case have been confirmed.

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