First Record of the Soil-feeding Higher Termites (Isoptera: Termitidae) from Okinawa Island, the Central Ryukyus, Japan

Some of termites have been introduced outside their native ranges, and it has been suggested that both wood-eating and wood-nesting lifestyles are critical for the transportation of propagules. Here, we present the first record of the soil-feeding and soil-nesting termite Pericapritermes nitobei (Isoptera: Termitidae) in the Motobu Peninsula on the northern part of Okinawa Island in the Central Ryukyus. The fact that the previous extensive surveys of termites in the Ryukyu Archipelago did not detect P. nitobei in the Central Ryukyus, including the Motobu Peninsula, and its discontinuous distribution, indicate that P. nitobei has been recently introduced into the Motobu Peninsula of Okinawa Island from the Yaeyama Islands, similar to the fungus-growing and soil-nesting termite Odontotermes formosanus (Isoptera: Termitidae). Together with O. formosanus in the southern part of Okinawa Island, our findings in this study raise the possibility that non-wood-feeding and non-wood-nesting termites can be introduced and established outside their native ranges by human activities

Enhanced heterozygosity from male meiotic chromosome chains is superseded by hybrid female asexuality in termites

Although males are a ubiquitous feature of animals, they have been lost repeatedly in diverse lineages. The tendency for obligate asexuality to evolve is thought to be reduced in animals whose males play a critical role beyond the contribution of gametes, for example, via care of offspring or provision of nuptial gifts. To our knowledge, the evolution of obligate asexuality in such species is unknown. In some species that undergo frequent inbreeding, males are hypothesized to play a key role in maintaining genetic heterozygosity through the possession of neo-sex chromosomes, although empirical evidence for this is lacking. Because inbreeding is a key feature of the life cycle of termites, we investigated the potential role of males in promoting heterozygosity within populations through karyotyping and genome-wide single-nucleotide polymorphism analyses of the drywood termite Glyptotermes nakajimai. We showed that males possess up to 15 out of 17 of their chromosomes as sex-linked (sex and neo-sex) chromosomes and that they maintain significantly higher levels of heterozygosity than do females. Furthermore, we showed that two obligately asexual lineages of this species—representing the only known all-female termite populations—arose independently via intraspecific hybridization between sexual lineages with differing diploid chromosome numbers. Importantly, these asexual females have markedly higher heterozygosity than their conspecific males and appear to have replaced the sexual lineages in some populations. Our results indicate that asexuality has enabled females to supplant a key role of males

A Japanese perspective on the decline of robust technologies and changing technological paradigms in housing construction: issues for construction management research

Based on the concept of construction as a project-based economic activity, Steven Groak offered the idea of a technological paradigm to represent project-based technology fusion that is adaptive to the uncertainties embodied within construction projects. This paper discusses further research topics raised by the idea of the technological paradigm from a Japanese perspective. It verifies the effectiveness of Groak's notion by exemplifying phenomena identified in Japanese construction practices. First, the paper confirms how declining robust technologies are generating innovative activities in construction projects. Second, a 'horizontal evolution' case study is presented as evidence that the strategies engendered by the technological paradigm outperform those from the industrial paradigm. Then the paper identifies and focuses on the informality of project-based technology fusion. Relevant research topics are discussed, such as the unpredictability of system configuration, the integration of knowledge and know-how, and the regulatory framework for extending positive informality. It is concluded that the following topics have considerable significance for construction management research: (a) methodology to evaluate 'robust limits'; (b) the process of project-to-project technology transfer and evolution; (c) organization formation of project-based technology fusion; and (d) regulatory framework that embodies informality to activate project-based technology fusion.Technological Paradigm Project-BASED Technology Fusion Robust Technology Organizational Learning,

Comparative stability analysis of demand-side and supply-side input-output models: the case of Japan, 1960-90

The results of comparative stability analysis of demand- and supply-side input-output models using the Japanese data are presented, together with the results of the comparison between the comparative stability analysis of the two models using the Japanese, UK and US data. The results of comparative stability analysis of the two models using the US data were reported elsewhere (Bon, 1986), and the results of the analysisusing the UK data were presented in this journal (Bon and Xu Bing, 1993). The forecasts of sectoral and total output of the two models are generated with known final demand and value added figures from subsequent tables, and are compared with known output figures for benchmark years. The results of the three studies are similar in part. The demand-side model performs somewhat better in terms of total output forecasts, but the supply-side performs somewhat better for a larger number of sectors. Also, in all three countries the supply-side model provides markedly superior forecasts for 'mature' sectors, such as agriculture and mining. However, there are some notable differences between Japan, on the one hand, and the UK and USA, on the other. In particular, the construction sector's performance is predicted better by the demand-side model in Japan, whereas the supply-side model produces better construction forecasts in the case of the UK and USA. Some other differences regarding several other sectors may be due to different aggregation scheme. Both models should be used to determine the extent to which an economy or a sector are demand- or supply-driven.

A Theory on Measuring Organizational Robustness of Fire Prevention Technology Development in Japanese High-Rise Building Projects

In this paper the fundamentals and necessities of technology development projects are discussed through organizational capabilities. These capabilities are examined under “Resources, Processes, and Priorities” of technology development business models. The ideal balance between these capabilities generate the organizational robustness. However, determining the essential capabilities, their correlative structure and comparison with the actual performance of the project is a complicated issue. Therefore, the “Robustness Equilibrium Theory” is developed to form an evaluation guideline which helps to figure out the ideal balance among the organizational capabilities within projects explicitly. The theory is applied experimentally to the case of fire prevention technology development for high-rise buildings in Japan. Discussions about vulnerabilities in Japanese cases are aroused upon the findings.</p