Thiamine tetrahydrofurfuryl disulfide promotes voluntary activity through dopaminergic activation in the medial prefrontal cortex

A physically active lifestyle is associated with better health in body and mind, and it is urgent that supporting agents for such lifestyles be developed. In rodents, voluntary locomotor activity as an active physical behavior may be mediated by dopaminergic neurons (DNs). Thiamine phosphate esters can stimulate DNs, and we thus hypothesized that thiamine tetrahydrofurfuryl disulfide (TTFD), a thiamine derivative, promotes locomotor activity via DNs in rats. Acute i.p. administration of TTFD enhanced rat locomotor activity in a normal cage. In vivo microdialysis revealed that TTFD-enhanced locomotor activity was synchronized with dopamine release in the medial prefrontal cortex (mPFC). Antagonism of the dopamine D1 receptor, but not D2 receptor, in the mPFC fully suppressed TTFD-enhanced locomotor activity. Finally, we found a TTFD dose-dependent increase in voluntary wheel running. Our findings demonstrate that DNs in the mPFC mediates TTFD-enhanced locomotor activity, suggesting the potential of TTFD to induce active physical behavior

Business strategy of Japanese System Integrators

Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management, 2006.Includes bibliographical references.The fundamental role of the System Integrators (Slers) is to provide customized IT systems or services that satisfy the unique requirements of each customer by integrating the various products and services that many IT companies produce. Originally, the IT companies in the different business segments such as the consulting business, hardware business, and software product business have complemented each other, and Slers played the roles of coordinators between these various IT companies and the customers. However, the business model of IT companies is rapidly changing. The firewalls separating business segments in the industry are becoming obsolete, and the Japanese Slers are now getting involved in the intense new competition. This thesis identifies key elements that influence the future business of Japanese Slers. It also proposes sound strategies that will enable Japanese Slers to grow solidly from the viewpoint of top management. From the technological viewpoint, my research finds that the commoditization and openness of technologies have made hardware and software product companies shift their business focuses from products to services. On the other hand, from the market viewpoint, customers are implementing the strategies that select and focus on core businesses.(cont.) Customers are actively trying to find outsourcing opportunities. The enterprise IT systems are no exception. Customers are trying to maximize business value using IT by distinguishing strategic systems that should be customized and owned by themselves from commodity systems that should reduce costs by adopting outsourcing services. Under these changing environments, Slers will be unable to maintain the sustainability of their business simply by improving their current core competency: system integration. I argue that Slers should create new relationships with complementers. Developing open-application platforms and sharing them with IT service providers widely will allow Slers to create a new software ecosystem that will provide mutually beneficial relationships with their current competitors. The Slers should not focus on cost reduction in offshore development; rather, global sourcing and global business expansion should be the center of the strategies for offshoring. I also show that the development of consulting services and the hybrid services that combine outsourcing and system integration services will be the keys to further growth.by Masahiro Kashibe.M.B.A

Formation and growth of intragranular fission gas bubbles in UO2 fuels with burnup of 6-83 GWd/t

The detailed characteristics of intragranular fission gas bubbles in UO fuel pellets (burnup: 6-83 GWd/t) before and after postirradiation annealing at 1600 and 1800°C have been examined by TEM and SEM fractography. In the base-irradiated fuels, a high density of small bubbles of about 2 nm in diameter precipitated uniformly in the matrix. When increasing burnup above 44 GWd/t, larger bubbles of 10-20 nm newly appeared in addition to the small bubbles. On heating at high temperatures, bubble growth was saturated within a few minutes. Enhanced coarsening of bubbles was found preferentially near the grain boundaries in the middle burnup fuels of 16-28 GWd/t and throughout the grains in the high burnup fuels of 44 and 83 GWd/t. The bubble growth during annealing was associated with a remarkable decrease of the bubble number density, and the relationship between bubble density N and mean diameter d was expressed as N α d. The coarsening was attributed to coalescence via bubble migration for moderately large bubbles of up to 50-60 nm, and to Ostwald ripening accompanied by a sufficient vacancy supply from external vacancy sources such as free surfaces, grain boundaries or irradiation-induced sub-grain boundaries for huge bubbles above 100 nm

Corrosion behavior of unirradiated oxide fuel pellets in high temperature water

In order to elucidate fuel wash-out behavior after the degraded secondary failure of LWR fuel rods, corrosion experiments in high temperature and high pressure water of 340°C and 15 MPa were conducted for unirradiated oxide fuels, two each of undoped UO with two different grain sizes, 5 wt% GdO- and 10 wt% GdO-doped UO. In degassed water of dissolved oxygen concentration (DO) equal to 10 ppb, no corrosion or oxidation was found, but the corrosion became noticeable above DO = 3 ppm. Pellet oxidation proceeded with UO formation along the grain boundaries and subsequent UO growth into enveloped UO grains. Consequently, the grain boundary penetration rate in the oxygenated water followed a diffusion-controlled parabolic law. Mismatch in the O/U ratio between the grain boundaries and interiors led to weakened boundaries, which is the cause of fuel wash-out in heavily degraded fuel rods. Both increases of grain size and GdO content were found to provide improved corrosion resistance