Excess heat evolution from nanocomposite samples under exposure to hydrogen isotope gases

Anomalous heat effect by interaction of hydrogen isotope gas and metal nanocomposites supported by zirconia or by silica has been examined. Observed absorption and heat evolution at RT were not too large to be explained by some chemical processes. At elevated temperatures of 200–300 °C, most samples with binary metal nanocomposites produced excess power of 3–24 W lasting for up to several weeks. The excess power was observed not only in the D-Pd·Ni system but also in the HPd·Ni system and HCu·Ni system, while single-element nanoparticle samples produced no excess power. The Pd/Ni ratio is one of the keys to increase the excess power. The maximum phase-averaged excess heat energy exceeded 270 keV/D, and the integrated excess heat energy reached 100 MJ/mol-M or 90 MJ/mol-H. It is impossible to attribute the excess heat energy to any chemical reaction; it is possibly due to radiation-free nuclear process.     

Regulation,pollution and heterogeneity in Japanese steam power generation companies

In this paper, the random stochastic frontier model is used to estimate the technical efficiency of Japanese steam power generation companies taking into regulation and pollution. The companies are ranked according to their productivity for the period 1976–2003 and homogenous and heterogeneous variables in the cost function are disentangled. Policy implication is derived.     

Overexpression of 1-Deoxy-D-xylulose-5-phosphate reductoisomerase gene in chloroplast contributes to increment of isoprenoid production

Plants synthesize a large number of isoprenoid compounds that are of industrial, nutritional and medicinal importance. 1-Deoxy-D-xylulose reductoisomerase (DXR) catalyzes the first committed step of plastidial isoprenoid-precursor biosynthesis. In the present study, we generated transplastomic tobacco plants that overproduced DXR from Synechosystis sp. strain PCC6803. The transformants showed increase in the content of various isoprenoids such as chlorophyll a, beta-carotene, lutein, antheraxanthin, solanesol and beta-sitosterol, indicating that the DXR reaction is one of the key steps controlling isoprenoid level in tobacco leaves. A qualitative change in isoprenoid composition was also observed. The growth phenotype of the transplastomic plants was similar to that of wild-type plants. These results showed that plastid metabolic engineering is useful in manipulating the yield of isoprenoids in plants.     

Integrated assessments of global warming issues and an overview of project PHOENIX—A comprehensive approach

This paper presents a new integrated assessment model (IAM) approach to global warming issues and reviews the ongoing approach to Project PHOENIX—Paths toward Harmony Of Environment, Natural resources and Industry compleX, developed by the Research Institute of Innovative Technology for the Earth (RITE). Existing integrated assessment approaches based on cost–benefit analysis calculate the potential costs under certain emission control policies, evaluating the warming damage in monetary terms and then exploring the preferable options. However, these approaches are not sufficient when we take into account the possibility of irreversible impacts, such as the shutdown of ocean thermohaline circulation and extinction of species. This project aims at providing integrated information and assessments for the global warming issues by gathering scientific information and by developing multimodels. For instance, the energy‐economics model DNE‐21 is expanded to generate the carbon emission path until 2200. A potential agricultural productivity model based on grid geographic information system (GIS) data is developed to assess the effect of climate change on crop production. DEARS, an intertemporal optimization multisector, multiregional, CGE energy‐economics model, is also developed to look at the effects of climate policy on industry sectors. Finally, we summarize the assessments and findings through the procedure in a ‘scoreboard’ for the assessment based on the expert judgments. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Human Gingival Integration-Free iPSCs; a Source for MSC-Like Cell

Mesenchymal stem cells (MSCs) are considered a potential autologous therapy for tissue engineering. The available procedures for MSC retrieval from patients are invasive, and their limited in vitro proliferation restricts their use in the treatment of damaged tissues. Therefore, it is important to establish an alternative and safe source of MSCs. The objective of this study was to demonstrate induced pluripotent stem cell (iPSC) generation from a combination of an accessible source tissue and an integration-free method; we also attempted the differentiation of iPSCs into MSC-like cells (MSLCs) for future autologous tissue engineering. iPSCs were derived from human gingival tissues, which are easily accessible in the field of dentistry, via the use of non-integrating episomal plasmids. Established iPSCs expressed embryonic stem (ES) cell-specific markers, as assessed by gene analysis and immunocytochemistry. Embryoid bodies and teratoma formation were formed from iPSCs, showing their capacity to differentiate into three germ layers. Furthermore, we were successful in differentiating iPSCs into MSLCs. They tested positively for their capacity of trilineage differentiation. Our results demonstrate that human gingival integration-free iPSCs, readily accessible stem cells generated using episomal plasmid vectors, are a promising source of MSLCs, which can be used in tissue regeneration.     

Identity of osteoclastogenesis inhibitory factor (OCIF) and osteoprotegerin (OPG): a mechanism by which OPG/OCIF inhibits osteoclastogenesis in vitro

The morphogenesis and remodeling of bone depends on the integrated activity of osteoblasts that form bone and osteoclasts that resorb bone. We previously reported the isolation of a new cytokine termed osteoclastogenesis inhibitory factor, OCIF, which specifically inhibits osteoclast development. Here we report the cloning of a complementary DNA of human OCIF. OCIF is identical to osteoprotegerin (OPG), a soluble member of the tumor-necrosis factor receptor family that inhibits osteoclastogenesis. Recombinant human OPG/OCIF specifically acts on bone tissues and increases bone mineral density and bone volume associated with a decrease of active osteoclast number in normal rats. Osteoblasts or bone marrow-derived stromal cells support osteoclastogenesis through cell-to-cell interactions. A single class of high affinity binding sites for OPG/OCIF appears on a mouse stromal cell line, ST2, in response to 1,25-dihydroxyvitamin D3. An anti-OPG/OCIF antibody that blocks the binding abolishes the biological activity of OPG/OCIF. When the sites are blocked with OPG/OCIF, ST2 cells fail to support osteoclastogenesis. These results suggest that the sites are involved in cell-to-cell signaling between stromal cells and osteoclast progenitors and that OPG/OCIF inhibits osteoclastogenesis by interrupting the signaling through the sites.     

Artificial Neuron and Synapse Realized in an Antiferromagnet/Ferromagnet Heterostructure Using Dynamics of Spin–Orbit Torque Switching

Efficient information processing in the human brain is achieved by dynamics of neurons and synapses, motivating effective implementation of artificial spiking neural networks. Here, the dynamics of spin–orbit torque switching in antiferromagnet/ferromagnet heterostructures is studied to show the capability of the material system to form artificial neurons and synapses for asynchronous spiking neural networks. The magnetization switching, driven by a single current pulse or trains of pulses, is examined as a function of the pulse width (1 s to 1 ns), amplitude, number, and pulse‐to‐pulse interval. Based on this dynamics and the unique ability of the system to exhibit binary or analog behavior depending on the device size, key functionalities of a synapse (spike‐timing‐dependent plasticity) and a neuron (leaky integrate‐and‐fire) are reproduced in the same material and on the basis of the same working principle. These results open a way toward spintronics‐based neuromorphic hardware that executes cognitive tasks with the efficiency of the human brain.     

Transient photoinduced 'hidden' phase in a manganite

Photoinduced phase transitions are of special interest in condensed matter physics because they can be used to change complex macroscopic material properties on the ultrafast timescale. Cooperative interactions between microscopic degrees of freedom greatly enhance the number and nature of accessible states, making it possible to switch electronic, magnetic or structural properties in new ways. Photons with high energies, of the order of electron volts, in particular are able to access electronic states that may differ greatly from states produced with stimuli close to equilibrium. In this study we report the photoinduced change in the lattice structure of a charge and orbitally ordered Nd(0.5)Sr(0.5)MnO(3) thin film using picosecond time-resolved X-ray diffraction. The photoinduced state is structurally ordered, homogeneous, metastable and has crystallographic parameters different from any thermodynamically accessible state. A femtosecond time-resolved spectroscopic study shows the formation of an electronic gap in this state. In addition, the threshold-like behaviour and high efficiency in photo-generation yield of this gapped state highlight the important role of cooperative interactions in the formation process. These combined observations point towards a 'hidden insulating phase' distinct from that found in the hitherto known phase diagram.     

Practical rearrangement methods for dynamic double‐array dictionaries

Double‐array structures have been widely used to implement dictionaries with string keys. Although the space efficiency of dynamic double‐array dictionaries tends to decrease with key updates, we can still maintain high efficiency using existing methods. However, these methods have practical problems of time and functionality. This paper presents several efficient rearrangement methods to solve these problems. Through experiments using real‐world datasets, we demonstrate that the proposed rearrangement methods are much more practical than existing methods.