174 research outputs found
Verification Conditions are Code
This paper presents a new theoretical result concerning Hoare Logic. It is shown here that the verification conditions which support a Hoare Logic program derivation are themselves sufficient to construct a correct implementation of the given pre-, post- condition specification. This property is mainly of theoretical interest, though it is possible that it may have some practical use, for example if predicative programming methodology is adopted. The result is shown to hold for both the original, partial correctness, Hoare logic, and also a variant for total correctness derivations
Model-Based Approaches for Validating Business Critical Systems
Developing a business critical system can involve considerable difficulties. This paper describes part of a new methodology that tackles this problem using co-evolution of models and prototypes to strengthen the relationship between modelling and testing. We illustrate how different modelling frameworks, Promela/SPIN and B/ProB/AtelierB, can be used to implement this idea. As a way to reinforce integration between modelling and testing, we were able to anticipate problems and guide the development of our software in a safer way, increasing our understanding of the system and its reliabilit
Intellectual disability, hate crime and other social constructions : A view from South Yorkshire
The category of hate crime is a recent legislative response to the increasing levels of anti-social, criminal and discriminatory behaviours and practices that target a wide spectrum of individuals on the basis of their identification within certain minority sociological subcultures. People with intellectual disability are often targeted for this kind of behaviour. Here we report on an evaluation of one English city's efforts to instigate a street-based scheme to offer some security and protection to its intellectually disabled citizens.
The physical location of the premises and the engagement of the staff employed therein has some bearing on their potential to be effective in offering shelter and support to distressed individuals. But even where premises are well situated with positive staffing the absence of local records to list the uptake of the scheme leaves room for doubt about its overall effectiveness. We make some recommendations for practice and suggest directions for further research
key words:
hate crime
intellectual disability
safe places
social inclusio
CoordMaude Simplifying Formal Coordination Specifications of Cooperation Environments
AbstractDeveloping concurrent applications in cooperative environments is an arduous task. This is mainly due to the fact that it is very difficult to specify the synchronized interaction between the entities composing the system. Using coordination models makes this task easier. The latest trends in this area suggest that to manage the successful implementation of complex systems, coordination models must support some key features regarding the coordination constraints: their separated specification, their unanticipated evolution and their dynamic change. However, supporting these features is not only a technical challenge: it must be also guaranteed that the application of a separately specified coordination pattern to a set of encapsulated entities, or the change of the coordination constraints in an already running software system will not produce semantic errors. This is just the problem focused in this paper. In particular, a method for generating formal interpretable specifications reproducing coordinated environments is presented. The method is based on the Coordinated Roles coordination model and makes use of Maude as a formal language. The benefits obtained are: (i) easy specification using the coordination model syntax, (ii) automatic generation of the corresponding formal specification and (iii) simulation of system behaviour
What kind of abuse is him spitting in my food?: Reflections on the similarities between disability hate crime, so-called ‘mate’ crime and domestic violence against women with intellectual disabilities
Domestic violence against women with learning disabilities is a wholly under-researched topic. A recent study indicated that there are strong parallels between domestic violence, disability hate crime and ‘mate’ crime. This paper explores these similarities and argues that rather than treating them as discreet phenomena, we need to make the connections and re-affirm the commitment that feminist scholars and activists made long ago, namely to take violence committed in private as seriously as that committed in public
Identification of a Novel Marine Fish Virus, Singapore Grouper Iridovirus-Encoded MicroRNAs Expressed in Grouper Cells by Solexa Sequencing
BACKGROUND: MicroRNAs (miRNAs) are ubiquitous non-coding RNAs that regulate gene expression at the post-transcriptional level. An increasing number of studies has revealed that viruses can also encode miRNAs, which are proposed to be involved in viral replication and persistence, cell-mediated antiviral immune response, angiogenesis, and cell cycle regulation. Singapore grouper iridovirus (SGIV) is a pathogenic iridovirus that has severely affected grouper aquaculture in China and Southeast Asia. Comprehensive knowledge about the related miRNAs during SGIV infection is helpful for understanding the infection and the pathogenic mechanisms. METHODOLOGY/PRINCIPAL FINDINGS: To determine whether SGIV encoded miRNAs during infection, a small RNA library derived from SGIV-infected grouper (GP) cells was constructed and sequenced by Illumina/Solexa deep-sequencing technology. We recovered 6,802,977 usable reads, of which 34,400 represented small RNA sequences encoded by SGIV. Sixteen novel SGIV-encoded miRNAs were identified by a computational pipeline, including a miRNA that shared a similar sequence to herpesvirus miRNA HSV2-miR-H4-5p, which suggests miRNAs are conserved in far related viruses. Generally, these 16 miRNAs are dispersed throughout the SGIV genome, whereas three are located within the ORF057L region. Some SGIV-encoded miRNAs showed marked sequence and length heterogeneity at their 3' and/or 5' end that could modulate their functions. Expression levels and potential biological activities of these viral miRNAs were examined by stem-loop quantitative RT-PCR and luciferase reporter assay, respectively, and 11 of these viral miRNAs were present and functional in SGIV-infected GP cells. CONCLUSIONS: Our study provided a genome-wide view of miRNA production for iridoviruses and identified 16 novel viral miRNAs. To the best of our knowledge, this is the first experimental demonstration of miRNAs encoded by aquatic animal viruses. The results provide a useful resource for further in-depth studies on SGIV infection and iridovirus pathogenesis
Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.
Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability
An Adaptive Time Management System for Student Learning
We present a modular framework for an adaptive, position-aware student time management system, and a prototype imlementation distributed between a desktop PC and a PDA. The system uses an adapted version of Soloman & Felder's Index of Learning Styles questionnaire to determine the student's learning style. This is matched with the teaching style of module, acquired by using a complementary teaching style questionnaire, to create an individual study plan for a user-defined learning task hierarchy. Based on user feedback the schedule is continually adapted using a multi-layered neural network. The mobile part of the system uses GPS data to launch position-related reminders. The novelty of our approach is its comprehensiveness, combining aspects of education theory, time management, machine learning, and position-awareness in a single framework. Remaining work includes the integration into the university IT infrastructure and a thorough evaluation by a representative group of students
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