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Because the discoordination between swallowing and respiration may cause severe respiratory disorders such as aspiration pneumonia, understanding the neuronal mechanisms underlying such coordination is important. Recently, it was reported that medullary noradrenergic neurons are involved in evoking esophageal-gastric relaxation reflex, leading to a hypothesis that such neurons are also involved in swallowing-respiration coordination. We tested this hypothesis using an in vitro brain-stem preparation obtained from neonatal rats. A temporal inhibition of respiratory rhythm was consistently observed when swallowing activity was induced by electrical stimulations to the supralaryngeal nerve. We found that a broad adrenergic receptor agonist, norepinephrine, markedly blocked the swallowing-induced temporal inhibition of respiration. Further studies revealed that swallowing-induced respiratory inhibition is blocked by an α2-adrenergic receptor agonist and enhanced by an α2-adrenergic receptor antagonist, indicating an important role of α2-adrenergic receptors in regulation of the coordination between swallowing and respiration in vitro.

[1] We demonstrate the ability of 1-Hz Global Positioning System (GPS) data to infer a medium-sized (M6 class) earthquake source process through an inversion study of the 2008 Iwate-Miyagi Nairiku, Japan, earthquake (M∼6.9). 1-Hz GPS waveforms for this earthquake are compared, and show good agreement with strong motion waveforms. Ground motions are well recorded at a sufficient number of GPS stations in and around source region, allowing us to perform waveform inversion using 1-Hz GPS data only. The 1-Hz GPS inversion result shows fairly good agreement with a joint inversion of geodetic and strong motion data, such as the seismic moment (Mw∼6.9), cumulative slip distribution, and rupture propagation. Such agreements demonstrate that 1-Hz GPS is able to infer the dynamic features of the rupture process as well as permanent (or static) slip even for a M6 class medium-sized earthquake.

The finding that the vomer plays a crucial role in maxillary growth suggests that the bilateral cleft configuration of unilateral cleft lip and palate (UCLP), in which the vomer is detached from the non-cleft-side secondary hard palate, negatively influences palatal development, and this hypothesis was tested. Sixty persons with complete UCLP, including those with the vomer detached from (n = 30, b-UCLP) and attached to (n = 30, u-UCLP) the secondary hard palate, were analyzed morphologically, with the use of cast models taken at 10 days, 3 mos, and 12 mos of age. The anterio-posterior palatal length at 12 mos of age in those with b-UCLP was significantly shorter than that in those with u-UCLP, by 8.7% (p < 0.05). In addition, palatal width development in the first year in those with b-UCLP was also significantly retarded. These results suggest that the uncommon bilateral cleft subtype in UCLP should be included in the cleft classification.

By using several digital video cameras with omni-directional sensors, complete views of the activities at some place can be recorded as omni-directional videos. We utilize this technique for developing the Retrax System, which provides video-based virtual space environments as part of the Digital City infrastructure. The system aims to realize applications that are not possible with conventional video database systems, such as human activities and communications on computer networks based on recorded video data. This system archives the activities at some place in the real world and provides a virtual space based on the archived data for collaboration among users, such as walking, annotating, and communication. The user interface of the system bridges the real and virtual spaces or past and current human activities. This paper describes the purpose and usage of the system, and then introduces its architecture, data models, and the query language. Because both video data and hypermedia data are essential to the system, a query mechanism dealing with both types of data is required. The proposed query language is designed as an extension of SQL and realizes flexible management of both types of data.

In order to utilize geographic web information for digital city applications, we have been developing a geographic web search system, KyotoSEARCH. When users retrieve geographic information on the web, specifying geographic location is an essential function. However, most current web search systems do not utilize location information sufficiently well to identify the user's intentions; available methods employ just keywords (for location names) and limited map functions. Furthermore, most map interfaces are used to select a determined geographic-hierarchy level or point to a specific location (sometimes specifying a radius). In this paper, we introduce two-dimensional range query processing for geographic web search, where users are able to specify a geographic area freely on a map interface. In order to handle such range queries more rapidly and efficiently, we adopt geometric operations to retrieve proper web pages. Without optimization techniques, however, the recall and precision of the search results become very low. Major problems come from erroneous extension of the computed geographic area due to i) same names for different geographic objects/locations (geowords), ii) redundant geographic hierarchy information, and iii) existence of non-important geowords. By resolving these problems, we can improve range query processing for geographic data. To that end, we propose an effective geographic scope optimization method for that supports geometric operations in geographic web search; experiments conducted on an implemented system are described.

CSCW (computer supported cooperative work) systems are required to support both flexibility and restriction of users in collaboration when users have different roles and capabilities or work status changes dynamically during collaboration. We propose a workspace management mechanism to meet these requirements. The mechanism provides each user with an integrated workspace, which unifies artifacts in different levels of work. Access control is a part of the workspace management mechanism. The design of the access control mechanism intends to simplify the specifications and status of access control. Users can easily change access permission during collaboration and grasp the situation of access control by precise workspace awareness information.

VIEW Media is a cooperative hypermedia system, which supports cooperative work utilizing hypermedia documents. It provides fundamental functions for cooperative work support systems and enables developers to construct various groupware such as distributed presentation systems, education systems, conference systems, and so forth. This system provides a powerful and flexible mechanism of customization. The mechanism can alter presentation, structure, behavior and authority of hypermedia documents and workspace, which supports dynamic change of roles of users. This paper describes the purpose of VIEW Media, its basic model and implementation, and a user interface which supports conferences among users who have different access rights to shared documents.

In distributed conference systems, participants get access to the shared documents through the computer network. The authors describe requirements in distributed conferences regarding access rights to shared documents. We give four categories of hypermedia representation based on access rights and two principles of human interface design to avoid mismatch between access rights and oral communication. We have developed the Channel Checker, which supports Non-WYSIWIS user interface for hypermedia based conferences. It allows participants to confirm users' access rights information and to communicate smoothly in conferences. By using this interface, users can synchronize the audio communication channel changes with their pointer on the shared document browser. The prototype of the Channel Checker is implemented on Java and JavaScript with an HTML browser.

Distributed multi-user hypermedia environments provide not only information-sharing mechanisms but also user collaboration/communication facilities. The provision of integrated views of heterogeneous information resources is necessary to create a common understanding among the users, who are possibly distributed in terms of geography and time. However, the requirements of customization must also be considered, since such diverse users would want to personalize their views of shared information. In order to integrate these views while considering the requirements of flexible customization, we propose cooperative view mechanisms of Dexter-based hypermedia systems, introducing environmental objects and their participation relationships. The mechanisms instantiate hypermedia deputies on the screen using participation relationships of the users, hypermedia components and environments. The relationships are also used for the purpose of supporting awareness. Using a novel user collaboration facility, the relationships are visualized so that users can easily recognize other users and/or user groups having the same, slightly different or very different views. Attributes of environment objects are discussed so that the mechanisms can be effectively utilized in computer-supported cooperative work settings such as distance presentations, virtual offices and virtual classrooms.

We have examined the rupture process of the 2010 Yushu, China, earthquake, which occurred in the eastern Tibetan plateau. Based on the results of centroid location grid searches, the aftershock distribution, and InSAR observations, we first constructed a left-lateral strike-slip bending fault model. We then carried out joint inversions of the teleseismic waveform data and InSAR data using various rupture front velocities. We obtained the optimum source model with a seismic moment of 2.3 × 1019 N m (Mw ∼ 6.8), where the rupture velocity was found to be slightly faster than the shear wave velocity of the crust in this region. This supershear rupture velocity resulted in severe damage in and around the county seat of Yushu, which is located in the forward rupture direction of the source model. The features of this event, such as the shallow and fast rupture propagation may represent a seismic feature of the tectonic activity in the eastern Tibetan plateau.

The recurring devastating earthquake that occurs in the Nankai Trough subduction zone between the Philippine Sea plate and the Eurasian plate has the potential to cause an extremely dangerous natural disaster in the foreseeable future. Many previous studies have assumed interplate-coupling ratios for this region along the trench axis using onshore geodetic data in order to understand this recursive event. However, the offshore region that has the potential to drive a devastating tsunami cannot be resolved sufficiently because the observation network is biased to the land area. Therefore, the Hydrographic and Oceanographic Department of Japan constructed a geodetic observation network on the seafloor along the Nankai Trough using a GPS-acoustic combination technique and has used it to observe seafloor crustal movements directly above the Nankai Trough subduction zone. We have set six seafloor sites and cumulated enough data to determine the displacement rate from 2006 to January 2011. Our seafloor geodetic observations at these sites revealed a heterogeneous interplate coupling that has three particular features. The fast displacement rates observed in the easternmost area indicate strong interplate coupling (>75%) around not only the future Tokai earthquake source region but also the Paleo-Zenisu ridge. The slow displacement rates near the trench axis in the Kumano-nada Sea, a shallow part of the 1944 Tonankai earthquake source region, show a lower coupling ratio (50% to 75%). The slow displacement rate observed in the area shallower than the 1946 Nankaido earthquake source region off Cape Muroto-zaki reflects weakening interplate coupling (about 50%) probably due to a subducting seamount. Our observations above the subducting ridge and seamount indicate that the effect of a subducting seamount on an interplate-coupling region depends on various conditions such as the geometry of the seamount and the friction parameters on the plate boundary.

Since it is necessary to realize virtual organizations in networks, to develop systems to be used for realizing various kinds of cooperation support among users is very important as a basis of virtual organizations. VIEW Media has been developed for such a purpose, utilizing CSCW (Computer Supported Cooperative Work) and database technologies. By introducing the concept of environment, VIEW Media supports flexible information sharing mechanisms. The major purpose of this paper is to show the advantages of the environment model for flexible sharing. Several well-known models are compared and then a representative model, the room model, is selected for comparison to develop the same application. Since the environment model is more general than the room model, we decided to develop "debate systems" which are rather complicated yet can be realized by both models. Debate systems can be regarded as generalization of conference systems and thus we believe the comparison is appropriate. By real usage of debate systems developed by VIEW Media (the environment model) and TeamWave (the room model), the environment model is shown to be suitable for such applications.

Repeatedly performing the GPS-acoustic seafloor positioning, we first succeeded in detecting non-volcanic seafloor movements on the Philippine Sea plate (PHS) subducting along the Sagami Trough. At a seafloor geodetic site on the northernmost part of the PHS off the Boso Peninsula, we detected significant eastward motion with respect to the central part of the PHS. This is unaccountable by the coupling between the Pacific plate and the PHS along the Izu-Bonin (Ogasawara) Trench because it would cause the westward elastic deformation at BOSS. It is rather consistent with the rigid motion of the tectonic block in the fore-arc along the Izu-Bonin Trench, associated with the back-arc rift. The other site on the western side of the Sagami Bay had moved toward the north relative to the Izu Peninsula. It suggests that the Izu microplate obviously moves relative to the northern PHS. The difference between the velocities of the Sagami Bay and the Izu Peninsula indicates the coupling on the boundary fault as well.