Superdatabases for Composition of Heterogeneous Databases

Superdatabases are designed to compose and extend databases. In particular, superdatabases allow consistent update across heterogeneous databases. The key idea of superdatabase is hierarchical composition of element databases. For global crash recovery, each element database must provide local recovery plus some kind of agreement protocol, such as two-phase commit. For global concurrency control, each element database must have local synchronization with an explicit serial order, such as two-phase locking, timestamps, or optimistic methods. Given element databases satisfying the above requirements, the superdatabase can certify the serializability of global transactions through a concatenation of local serial order. Combined with previous work on heterogeneous databases, including unified query languages and view integration, now we can build heterogeneous databases which are consistent, adaptable, and extensible by construction

A Systematic Review of the Soteria Paradigm for the Treatment of People Diagnosed With Schizophrenia

Background: The “Soteria paradigm” attempts to support people diagnosed with schizophrenia spectrum disorders using a minimal medication approach. Interest in this approach is growing in the United Kingdom, several European countries, North America, and Australasia. Aims: To summarize the findings from all controlled trials that have assessed the efficacy of the Soteria paradigm for the treatment of people diagnosed with schizophrenia spectrum disorders. Methods: A systematic search strategy was used to identify controlled studies (randomized, pseudorandomized, and nonrandomized) employing the Soteria paradigm to treat adults and adolescents meeting the criteria for schizophrenia spectrum disorders according to International Classification of Diseases and Diagnostic and Statistical Manual for Mental Disorders criteria. Results: We identified 3 controlled trials involving a total of 223 participants diagnosed with first- or second-episode schizophrenia spectrum disorders. There were few major significant differences between the experimental and control groups in any of the trials across a range of outcome measures at 2-year follow-up, though there were some benefits in specific areas. Conclusions: The studies included in this review suggest that the Soteria paradigm yields equal, and in certain specific areas, better results in the treatment of people diagnosed with first- or second-episode schizophrenia spectrum disorders (achieving this with considerably lower use of medication) when compared with conventional, medication-based approaches. Further research is urgently required to evaluate this approach more rigorously because it may offer an alternative treatment for people diagnosed with schizophrenia spectrum disorders

Achieving efficiency and portability in systems software: a case study on POSIX-compliant multithreaded programs

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Execution Autonomy in Distributed Transaction Processing

We study the feasibility of execution autonomy in systems with asynchronous transaction processing based on epsilon-serializability (ESR). The abstract correctness criteria defined by ESR are implemented by techniques such as asynchronous divergence control and asynchronous consistency restoration. Concrete application examples in a distributed environment, such as banking, are described in order to illustrate the advantages of using ESR to support execution autonomy

An Overview of the Synthesis Operating System

An operating system (OS) maps a model of computation, defined by its kernel interface, onto the underlying hardware. A. simple and intuitive model of computation makes it easy for programmers to write applications. An efficient implementation of the mapping makes the applications run fast. Typical OS interfaces for von Neumann hardware include processes (CPU), address spaces (memory), and I/O devices (I/O). An OS for distributed and multiprocessor systems must support parallel processing and inter-process communications. Designed for the distributed and multiprocessor systems of today and tomorrow, Synthesis is an example of the new generation of OS's. The Synthesis model of computation based on macro dataflow makes parallel programming easy. The Synthesis implementation uses innovative ideas from areas as different as compilers and control systems, Kernel Code Synthesis. Reduced Synchronization, Fine-Grain Scheduling, and Valued Redundancy provide high performance. Emulation of guest OS's in Synthesis allow existing software written for other OS's to run on Synthesis with little or no modification. Using hardware and software emulating a SUN-3/160 running SUN OS, the current version of Synthesis kernel achieves several times to several dozen times speed up for UNIX kernel calls

The Cerebellum and SIDS: Disordered Breathing in a Mouse Model of Developmental Cerebellar Purkinje Cell Loss during Recovery from Hypercarbia.

The cerebellum assists coordination of somatomotor, respiratory, and autonomic actions. Purkinje cell alterations or loss appear in sudden infant death and sudden death in epilepsy victims, possibly contributing to the fatal event. We evaluated breathing patterns in 12 wild-type (WT) and Lurcher mutant mice with 100% developmental cerebellar Purkinje cell loss under baseline (room air), and recovery from hypercapnia, a concern in sudden death events. Six mutant and six WT mice were exposed to 4-min blocks of increasing CO2 (2, 4, 6, and 8%), separated by 4-min recovery intervals in room air. Breath-by-breath patterns, including depth of breathing and end-expiratory pause (EEP) durations during recovery, were recorded. No baseline genotypic differences emerged. However, during recovery, EEP durations significantly lengthened in mutants, compared to WT mice, following the relatively low levels of CO2 exposure. Additionally, mutant mice exhibited signs of post-sigh disordered breathing during recovery following each exposure. Developmental cerebellar Purkinje cell loss significantly affects compensatory breathing patterns following mild CO2 exposure, possibly by inhibiting recovery from elevated CO2. These data implicate cerebellar Purkinje cells in the ability to recover from hypercarbia, suggesting that neuropathologic changes or loss of these cells contribute to inadequate ventilatory recovery to increased environmental CO2. Multiple disorders, including sudden infant death syndrome (SIDS) and sudden unexpected death in epilepsy (SUDEP), appear to involve both cardiorespiratory failure and loss or injury to cerebellar Purkinje cells; the findings support the concept that such neuropathology may precede and exert a prominent role in these fatal events

Regulation of APC/C-Cdh1 and Its Function in Neuronal Survival

This paper presents WebCQ, a prototype of a large-scale Web information monitoring system, WebCQ is designed to discover and detect changes to the World Wide Web (the Web) pages efficiently, and to notify users of interesting changes with a personalized customization. The system consists of four main components: a change detection robot that discovers and detects changes, a proxy cache service that reduces the communication traffics to the original information provider on the remote server, a tool that highlights changes between the web page last seen and the new version of the page, and a change notification service that delivers interesting changes and fresh information to the right users at the right time. A salient feature of our change detection robot is its ability to support various types of web page sentinels for finding and displaying interesting changes to web pages. This paper describes the WebCQ system with an emphasis on general issues in designing and engineering a la..

A Formal Characterization of Epsilon Serializability

Epsilon Serializability (ESR) is a generalization of classic serializability (SR). ESR allows some limited amount of inconsistency in transaction processing (TP), through an interface called epsilon-transactions (ETs). For example, some query ETs may view inconsistent data due to non-SR interleaving with concurrent updates. In this paper, we restrict our attention to the situation where query-only ETs run concurrently with consistent update transactions that are SR without the ETs. This paper presents a formal characterization of ESR and ETs. Using the ACTA framework, the first part of this characterization formally expresses the inter-transaction conflicts that are recognized by ESR and, through that, defines ESR, analogous to the manner in which conflict-based serializability is defined. The second part of the paper is devoted to deriving expressions for: (1) the inconsistency in the values of data -- arising from ongoing updates, (2) the inconsistency of the results of a query ““ arising from the inconsistency of the data read in order to process the query, and (3) the inconsistency exported by an update ET - arising from ongoing queries reading uncommitted data produced by the update ET. These expressions are used to determine the preconditions that ET operations have to satisfy in order to maintain the limits on the inconsistency in the data read by query ETs, the inconsistency exported by update ETs, and the inconsistency in the results of queries. This determination suggests possible mechanisms that can be used to realize ESR

Performance Evaluation of Global Reading of Entire Databases

Using simulation and probabilistic analysis, we study the performance of an algorithm to read entire databases with locking concurrency control allowing multiple readers or an exclusive writer. The algorithm runs concurrently with the normal transaction processing (on-the-fly) and locks the entities in the database one by one (incremental). The analysis compares different strategies to resolve the conflicts between the global read algorithm and update. Since the algorithm is parallel in nature, its interference with normal transactions is minimized in parallel and distributed databases. A simulation study shows that one variant of the algorithm can read the entire database with very little overhead and interference with the updates

Minimal-medication approaches to treating schizophrenia

UK guidelines for treating people diagnosed with schizo phrenia currently emphasise the primacy of antipsychotic medication, with or without psycho-socially based interventions as circumstances dictate. We now see increasing calls, most notably from mental health service users, for the provision of ‘whole-person-based’, minimal-medication approaches to treating people with this diagnosis. This article is intended to locate the development of such approaches within the history of modern and pre-modern psychiatry and, in doing so, summarise the available evidence base that underpins their efficacy