Peer-to-peer (P2P)-Grid systems are being investigated as a platform for converging the Grid and P2P network in the construction of large-scale distributed applications. The highly dynamic nature of P2P-Grid systems greatly affects the execution of the distributed program. Uncertainty caused by arbitrary node failure and departure significantly affects the availability of computing resources and system performance. Checkpoint-and-restart is the most common scheme for fault tolerance because it periodically saves the execution progress onto stable storage. In this paper, we suggest a checkpoint-and-restart mechanism as a fault-tolerant method for applications on P2P-Grid systems. Failure detection mechanism is a necessary prerequisite to fault tolerance and fault recovery in general. Given the highly dynamic nature of nodes within P2P-Grid systems, any failure should be detected to ensure effective task execution. Therefore, failure detection mechanism as an integral part of P2P-Grid systems was studied. We discussed how the design of various failure detection algorithms affects their performance in average failure detection time of nodes. Numerical analysis results and implementation evaluation are also provided to show different average failure detection times in real systems for various failure detection algorithms. The comparison shows the shortest average failure detection time by 8.8s on basis of the WP failure detector. Our lowest mean time to recovery (MTTR) is also proven to have a distinct advantage with a time consumption reduction of about 5.5s over its counterparts.

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Background In this study, we aim to highlight the transformation of self-image in patients with type 1 diabetes after diagnosis. Our objective in examining the self-image of these patients is to provide practical insights for nursing, as well as a basic reference for understanding patients.

Methods The participants were 15 patients (2 men and 13 women) over 20 years of age who visited an outpatient setting to treat type 1 diabetes and had no serious complications, and who agreed to participate in the study. Semi-structured interviews were conducted 1–2 times, with a duration of 60–75 minutes per person, from February 2016 to March 2017. We drew on Krippendorff’s (1999) content analysis to carry out our analysis.

Results We identified a total of 107 codes. The self-image of patients with type 1 diabetes was categorized into 8 subcategories and 4 categories. The 4 categories were ‘the wavering of a self-image that is distinct from the past,’ ‘loss of former self-image,’ ‘discovery of a new self-image,’ and ‘developing a new self-image.’ Ultimately, we were able to extract a fifth core category, ‘acquisition of a new self-image.’

Conclusion The self-image of patients with type 1 diabetes transformed from a negative to a positive one; ultimately, patients acquired a new self-image that was congruent with their ideal self-image. Our results showed that the new self-image that patients acquired through various experiences influenced motivation for treatment and continuation of self-care. When caring for patients with type 1 diabetes, it is crucial for healthcare professionals be aware of the meaning that patients derive from their disease and related difficulties, as well as to provide care while considering patients’ self-image.

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The "child" is a motif which Caryl Churchill has employed repeatedly in her plays. Regarding Churchill's strong focus on the child motif, Colin Chambers and Mike Prior have suggested that one could understand the use of the motif up to 1987 in the context of gender issues. This argument may be effective for understanding the child motif in Churchill's representative works written around 1980. However, this essay focuses on Churchill's earliest plays such as The Ants, Abortive and The Hospital at the Time of the Revolution, and argues that the representation of children in these plays cannot necessarily be reduced to a subsidiary of the theme of mother figures. This child motif, furthermore, offers a greater potential for the foregrounding of the distortions in our inner and outer worlds. First, through the examination of The Ants, the way in which the terror caused by a large-scale system of desertion (represented as "war" in this play) is conveyed through the child motif is made clear. Secondly, the way in which the existence (or non-existence) of an aborted baby is used to reveal a sense of loss in a seemingly affluent life is examined through Abortive. This is followed by a discussion of The Hospital, where, primarily through the representation of a schizophrenic teenage girl, the importance of the child motif in the foregrounding of the distorted power structure of the world is confirmed. (Here, the child motif mirrors the figure of the colonised, abused mentally and physically, which emphasises the viciousness of colonialism.) At the same time, the child motif in this play not only points to the distortion in the larger system of the world; the child is also depicted as the only subject who is able to recognise, and may even counter, the horrific nature of the system.

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This paper proposes a passive replication mechanism which establishes complete location and replication independence of program modules. The proposed method is based on an object model and a reliable broadcast mechanism, where each object has an automatic checkpointing mechanism within itself. The automatic checkpointing mechanism frees users from the need to designate checkpoints in application objects.
By the proposed mechanism, replication degree and execution mode of each object can be changed dynamically in accordance with the required reliability and responsibility, and also passive replication and active replication methods can be mixed. In addition, because checkpointing and failure detection are carried out by passive modules, extra operations for maintaining reliability can be removed from active modules.
The proposed method is applied to a train traffic control system; its effectiveness and performance characteristics are also described.

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