L-Qモデルは転移性脳腫瘍の定位放射線照射に適用可能か?

The biologically effective dose (BED) based on the linear-quadratic (LQ) model has been commonly used to evaluate the dose-effect relationships among the different fractionation schedules, but whether the LQ model is appropriate for hypofractionated (HF) high-dose stereotactic irradiation (STI) is uncertain. The validity of the model at high doses per fraction has been critically examined. In this study, STI of metastatic brain tumors was evaluated to suggest the applicability of the LQ model to HF high-dose radiotherapy. No significant difference was found between stereotactic radiosurgery (SRS) and HF stereotactic radiotherapy (SRT) in the analyses of 151 tumors. Furthermore, no significant differences were found among SRS, HF-SRT, and non-HF SRT in 117 metastatic lung adenocarcinomas. The results of this study suggest that BED calculation is a reasonable approach for careful dose-effect evaluation based on the LQ model for HF high-dose radiotherapy for metastatic brain tumors, especially lung adenocarcinomas.博士（医学）・甲第688号・平成30年9月26

Contractile Properties of Esophageal Striated Muscle: Comparison with Cardiac and Skeletal Muscles in Rats

The external muscle layer of the mammalian esophagus consists of striated muscles. We investigated the contractile properties of esophageal striated muscle by comparison with those of skeletal and cardiac muscles. Electrical field stimulation with single pulses evoked twitch-like contractile responses in esophageal muscle, similar to those in skeletal muscle in duration and similar to those in cardiac muscle in amplitude. The contractions of esophageal muscle were not affected by an inhibitor of gap junctions. Contractile responses induced by high potassium or caffeine in esophageal muscle were analogous to those in skeletal muscle. High-frequency stimulation induced a transient summation of contractions followed by sustained contractions with amplitudes similar to those of twitch-like contractions, although a large summation was observed in skeletal muscle. The results demonstrate that esophageal muscle has properties similar but not identical to those of skeletal muscle and that some specific properties may be beneficial for esophageal peristalsis

Direct and Indirect Induction of a Compensatory Phenotype that Alleviates the Costs of an Inducible Defense

Organisms often exhibit phenotypic plasticity in multiple traits in response to impending environmental change. Multiple traits phenotypic plasticity is complex syndrome brought on by causal relations in ecological and physiological context. Larvae of the salamander Hynobius retardatus exhibit inducible phenotypic plasticity of two traits, when at risk of predation by dragonfly larvae. One induced phenotype is an adaptive defense behaviour, i.e., stasis at the bottom of water column, directly triggered by the predation risk. Another one is a compensatory phenotype, i.e., enlarged external gills, for an unavoidable cost (hypoxia) associated with the induced defense. We identified two ways by which this compensatory phenotype could be induced. The compensatory phenotype is induced in response to not only the associated hypoxic conditions resulting from the induced defense but also the most primary but indirect cause, presence of the predator

Japan’s Identity in International Society: Constructing Identity as a ‘Peacebuilding State’

Since the end of the Cold War, the development of Japan’s foreign policy has shown a great level of relevance to regional and international security affairs. Regional instability and conflict in regions such as Asia, Eastern Europe and Africa, the onset of the global war on terror from 2001 onwards, and the recent rise of China in economic and security terms, have all continued to attract scholars and practitioners at home and abroad in analysing and understanding Japan’s foreign policy stance regarding these issues. More fundamentally, although it is not a new phenomenon, portrayals of Japan’s regional and international roles continue to serve as an essential element of their research interest. Researchers in this field often concern themselves with the following question: what sort of self-image of statehood is Japan trying to perceive and demonstrate in a changing international society? Indeed, the study of identity is of central importance to the field of Japanese studies. Recent research regarding the study of Japan’s identity in the security sector has focused either on the continuation of a long-lasting identity as a “peace state”, or an increasing change towards a more “internationally proactive state”. However, it overlooks evolving and mixed elements of such an identity from a broader historical perspective, and leaves questions with regard to the dynamics of identity construction. Literature regarding the emerging phenomenon of Japan’s involvement in peacebuilding indicates a promising direction for the examination of this aspect, but so far it underexplores the relationship between Japan’s identity and peacebuilding. Within a framework of qualitative research, this thesis investigates how Japan has constructed its identity as a “peacebuilding state”. It employs a framework to analyse a process of the construction of identity consisting of three aspects: articulation of self-perception by narratives (what Japan represents itself as by narratives); action commensurate with the narrative self-perception (how Japan acts in an effort to demonstrate that its representation fits Japan); and social recognition (how other members of the international audience recognise Japan’s self-perception and related actions). This research examines political discourse, media sources, opinion polls, and in- person interviews with key figures related to peacebuilding, and argues that the construction of Japan’s identity as a peacebuilding state has taken place in three ways: comprehensive peacebuilding efforts on the ground in a troubled region; taking a leadership role in international forums related to peacebuilding; and implementing human resource development for peacebuilding at home. It provides an alternative insight into the study of Japan’s identity in security sectors, and reinforces theoretical and empirical aspects of the relationship between identity and peacebuilding in the context of Japan

Constructing Peace in the Minds of People?: Roles of Japan in Psychosocial Reconstruction

This article seeks to add to the existing literature on Japans peacebuilding by examining its involvement in the psychosocial reconstruction of children in conflictaffected regions. It demonstrates that to this end Japan has implemented creative, recreational activities, and, to a lesser extent, community-building strategies. This article argues that there are three important implications of Japans involvement in psychosocial reconstruction for its own foreign policy: (1) psychological reconstruction can enhance its non-military approach to peacebuilding; (2) this field can potentially be another area of expertise in its own peacebuilding policy; and (3) in so doing, Japan may be able to carve out a niche in the field of international peacebuilding. This article concludes by identifying some limitations that can be developed into areas for future research

Japan’s Identity in International Society: Constructing Identity as a ‘Peacebuilding State’

Since the end of the Cold War, the development of Japan’s foreign policy has shown a great level of relevance to regional and international security affairs. Regional instability and conflict in regions such as Asia, Eastern Europe and Africa, the onset of the global war on terror from 2001 onwards, and the recent rise of China in economic and security terms, have all continued to attract scholars and practitioners at home and abroad in analysing and understanding Japan’s foreign policy stance regarding these issues. More fundamentally, although it is not a new phenomenon, portrayals of Japan’s regional and international roles continue to serve as an essential element of their research interest. Researchers in this field often concern themselves with the following question: what sort of self-image of statehood is Japan trying to perceive and demonstrate in a changing international society? Indeed, the study of identity is of central importance to the field of Japanese studies. Recent research regarding the study of Japan’s identity in the security sector has focused either on the continuation of a long-lasting identity as a “peace state”, or an increasing change towards a more “internationally proactive state”. However, it overlooks evolving and mixed elements of such an identity from a broader historical perspective, and leaves questions with regard to the dynamics of identity construction. Literature regarding the emerging phenomenon of Japan’s involvement in peacebuilding indicates a promising direction for the examination of this aspect, but so far it underexplores the relationship between Japan’s identity and peacebuilding. Within a framework of qualitative research, this thesis investigates how Japan has constructed its identity as a “peacebuilding state”. It employs a framework to analyse a process of the construction of identity consisting of three aspects: articulation of self-perception by narratives (what Japan represents itself as by narratives); action commensurate with the narrative self-perception (how Japan acts in an effort to demonstrate that its representation fits Japan); and social recognition (how other members of the international audience recognise Japan’s self-perception and related actions). This research examines political discourse, media sources, opinion polls, and in- person interviews with key figures related to peacebuilding, and argues that the construction of Japan’s identity as a peacebuilding state has taken place in three ways: comprehensive peacebuilding efforts on the ground in a troubled region; taking a leadership role in international forums related to peacebuilding; and implementing human resource development for peacebuilding at home. It provides an alternative insight into the study of Japan’s identity in security sectors, and reinforces theoretical and empirical aspects of the relationship between identity and peacebuilding in the context of Japan

Discourses of Civilisation in International Politics: The Case of Japan

Recent discourse in international politics has seen a remarkable increase in the use of the word ‘civilisation’. This phenomenon has stimulated research that seeks to investigate the concept of the ‘standard of civilisation’ in the historical development of international politics, and the implications that this has had and may continue to have on the regional and global level. In this context, this thesis examines the evolving idea of the standard of civilisation as it relates to Japan. Throughout this investigation, the thesis sheds light on a nexus between the discourse of civilisation and militarisation. The linkage between civilisation and militarisation is most evident in the debate over Japan’s remilitarisation in the post-Second World War era. In analysing this case, the thesis also points out the potential ramifications of the discourse of civilisation in international politics, including issues surrounding the promotion of liberal democracy and the military alliance relationship between the United States and Japan. The thesis concludes by stating the importance of an awareness of dangers that may manifest themselves as a consequence of the linkage between civilisation and militarisation

Conceptual schema of phenotypic plasticity in salamander larvae in the presence of dragonfly larvae.

<p>In this schema, “Predation risk” is the starting point and “Enlargement of the external gills” is the end point. Dotted arrows originate at possible signals, solid arrows show adaptive causal connections, and the hollow arrow points to an unavoidable cost. Thus, hypoxia is an unavoidable cost of the adaptive behavioural response “Decreased surfacing”. Enlargement of the external gills can be reached by two pathways, a multi-step pathway via the antipredator behaviour (decreased surfacing) and the consequent hypoxia, and a direct pathway via predator-produced cues.</p

Representative salamander larvae reared under low-oxygen conditions in the gill induction experiment.

<p>The individual on the left was subjected to the predator treatment and the one on the right to the no-predator treatment.</p