761 research outputs found
Sawja: Static Analysis Workshop for Java
Static analysis is a powerful technique for automatic verification of
programs but raises major engineering challenges when developing a full-fledged
analyzer for a realistic language such as Java. This paper describes the Sawja
library: a static analysis framework fully compliant with Java 6 which provides
OCaml modules for efficiently manipulating Java bytecode programs. We present
the main features of the library, including (i) efficient functional
data-structures for representing program with implicit sharing and lazy
parsing, (ii) an intermediate stack-less representation, and (iii) fast
computation and manipulation of complete programs
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Competing risks and deposit insurance governance convergence
Why do policies often seem to converge across countries at the same time? This question has been studied extensively in the diffusion literature. However, past research has not examined complex choice environments, especially where there are many alternatives. This article fills this gap in the literature. I show how Fine and Gray's Competing Risks Event History Analysis can be used to tease apart the causes of policy convergence. I apply the method to an examination of the reasons why, from the mid-1990s to 2007, many countries created independent deposit insurers. I find an interaction between international recommendations and regional peers' choices, particularly in the European Union. However, convergence appears to slow under the particular conditions of a banking crisis, regardless of how well independence is promoted. Possibly due to electoral incentives, democracies seem to have been more likely to create independent insurers. Ultimately, I demonstrate how competing risks analysis can help enable future research on policy choices, complementing methods previously applied in political economy. © The Author(s) 2013
Risk factors for high anti-HHV-8 antibody titers (≥1:51,200) in black, HIV-1 negative South African cancer patients: a case control study
Background: Infection with human herpesvirus 8 (HHV-8) is the necessary causal agent in the
development of Kaposi's sarcoma (KS). Infection with HIV-1, male gender and older age all increase
risk for KS. However, the geographic distribution of HHV-8 and KS both prior to the HIV/AIDS
epidemic and with HIV/AIDS suggest the presence of an additional co-factor in the development of
KS.
Methods: Between January 1994 and October 1997, we interviewed 2576 black in-patients with
cancer in Johannesburg and Soweto, South Africa. Blood was tested for antibodies against HIV-1
and HHV-8 and the study was restricted to 2191 HIV-1 negative patients. Antibodies against the
latent nuclear antigen of HHV-8 encoded by orf73 were detected with an indirect
immunofluorescence assay. We examined the relationship between high anti-HHV-8 antibody
titers (≥1:51,200) and sociodemographic and behavioral factors using unconditional logistic
regression models. Variables that were significant at p = 0.10 were included in multivariate analysis.
Results: Of the 2191 HIV-1 negative patients who did not have Kaposi's sarcoma, 854 (39.0%)
were positive for antibodies against HHV-8 according to the immunofluorescent assay. Among
those seropositive for HHV-8, 530 (62.1%) had low titers (1:200), 227 (26.6%) had medium titers
(1:51,200) and 97 (11.4%) had highest titers (1:204,800). Among the 2191 HIV-1 negative patients,
the prevalence of high anti-HHV-8 antibody titers (≥1:51,200) was independently associated with
increasing age (ptrend = 0.04), having a marital status of separated or divorced (p = 0.003), using
wood, coal or charcoal as fuel for cooking 20 years ago instead of electricity (p = 0.02) and
consuming traditional maize beer more than one time a week (p = 0.02; p-trend for increasing
consumption = 0.05) although this may be due to chance given the large number of predictors
considered in this analysis.
Conclusions: Among HIV-negative subjects, patients with high anti-HHV-8 antibody titers are
characterized by older age. Other associations that may be factors in the development of high anti-
HHV-8 titers include exposure to poverty or a low socioeconomic status environment and
consumption of traditional maize beer. The relationship between these variables and high anti-
HHV-8 titers requires further, prospective study
Impact of quality of evidence on the strength of recommendations: an empirical study
<p>Abstract</p> <p>Background</p> <p>Evidence is necessary but not sufficient for decision-making, such as making recommendations by clinical practice guideline panels. However, the fundamental premise of evidence-based medicine (EBM) rests on the assumed link between the quality of evidence and "truth" and/or correctness in making guideline recommendations. If this assumption is accurate, then the quality of evidence ought to play a key role in making guideline recommendations. Surprisingly, and despite the widespread penetration of EBM in health care, there has been no empirical research to date investigating the impact of quality of evidence on the strength of recommendations made by guidelines panels.</p> <p>Methods</p> <p>The American Association of Blood Banking (AABB) has recently convened a 12 member panel to develop clinical practice guidelines (CPG) for the use of fresh-frozen plasma (FFP) for 6 different clinical indications. The panel was instructed that 4 factors should play a role in making recommendation: quality of evidence, uncertainty about the balance between desirable (benefits) and undesirable effects (harms), uncertainty or variability in values and preferences, and uncertainty about whether the intervention represents a wise use of resources (costs). Each member of the panel was asked to make his/her final judgments on the strength of recommendation and the overall quality of the body of evidence. "Voting" was anonymous and was based on the use of GRADE (Grading quality of evidence and strength of recommendations) system, which clearly distinguishes between quality of evidence and strength of recommendations.</p> <p>Results</p> <p>Despite the fact that many factors play role in formulating CPG recommendations, we show that when the quality of evidence is higher, the probability of making a strong recommendation for or against an intervention dramatically increases. Probability of making strong recommendation was 62% when evidence is "moderate", while it was only 23% and 13% when evidence was "low" or "very low", respectively.</p> <p>Conclusion</p> <p>We report the first empirical evaluation of the relationship between quality of evidence pertinent to a clinical question and strength of the corresponding guideline recommendations. Understanding the relationship between quality of evidence and probability of making (strong) recommendation has profound implications for the science of quality measurement in health care.</p
Health and economic impact of HIV/AIDS on South African households: a cohort study
BACKGROUND: South African households are severely affected by human immunodeficiency virus / acquired immunodeficiency syndrome (HIV/AIDS) but health and economic impacts have not been quantified in controlled cohort studies. METHODS: We compared households with an HIV-infected member, and unaffected neighbouring households, in one rural and one urban area in Free State province, South Africa. Interviews were conducted with one key informant in each household, at baseline and six months later. We studied 1913 members of 404 households, with 94% and 96% follow up, respectively. Household and individual level analyses were done. RESULTS: Members of affected households, compared to members of unaffected households, were independently more likely to be continuously ill (adjusted odds ratio (OR) 2.1, 95% CI 1.3–3.4 at follow up), and to die (adjusted OR 3.4, 95% CI 1.0–11), mainly due to infectious diseases. Government clinics and hospitals were the main sources of health care. Affected households were poorer than unaffected households at baseline (relative income per person 0.61, 95% CI 0.49–0.76). Over six months expenditure and income decreased more rapidly in affected than in unaffected households (baseline-adjusted relative expenditure 0.86, 95% CI 0.75–0.99 and income 0.89, 95% CI 0.75–1.05). Baseline morbidity was independently associated with lower income and expenditure at baseline but not with changes over six months. CONCLUSIONS: HIV/AIDS affects the health and wealth of households as well as infected individuals, aggravating pre-existing poverty
Translation to practice: a randomised controlled study of an evidenced based booklet targeted at breast care nurses in the United Kingdom
BACKGROUND: In the United Kingdom (UK), it was documented that a problem of knowledge transfer existed within the speciality of breast-cancer care, thus depriving patients of receiving optimal care. Despite increasingly robust research evidence indicating recommendation of whole body exercise for people affected by breast cancer, commensurate changes to practice were not noted amongst breast-care nurses (BCNs).
AIM: To evaluate the effect of a targeted booklet, Exercise and Breast Cancer: A Booklet for Breast-Care Nurses, on changes in knowledge, reported practice, and attitudes of BCNs in the UK.
METHOD: A prospective, experimental approach was used for designing a pre- and post-test randomised controlled study. Comparisons of knowledge, reported practice, and attitudes based on responses to a questionnaire were made at two time-points in two groups of BCNs (control and experimental). The unit of randomisation and analysis was hospital clusters of BCNs. The sample comprised 92 nurses from 62 hospitals. Analysis consisted of descriptive statistics and clustered regression techniques: clustered logistic regression for knowledge items, clustered linear regression for knowledge scores, ologit for attitude and reported practice items, and clustered multiple regression for paired and multiple variable analysis.
RESULTS: A statistically significant increase in knowledge and changes in reported practice and attitudes were found. Robust variables affecting knowledge acquisition were: promotion of health, promotion of exercise, and understanding how exercise can reduce cancer-related fatigue.
DISCUSSION: The study has shown that evidence-based printed material, such as an information booklet, can be used as an effective research dissemination method when developed for needs, values, and context of a target audience.
CONCLUSIONS: This practical approach to research dissemination could be replicated and applied to other groups of nurses.</p
Alcohol imagery on New Zealand television
BACKGROUND: To examine the extent and nature of alcohol imagery on New Zealand (NZ) television, a content analysis of 98 hours of prime-time television programs and advertising was carried out over 7 consecutive days' viewing in June/July 2004. The main outcome measures were number of scenes in programs, trailers and advertisements depicting alcohol imagery; the extent of critical versus neutral and promotional imagery; and the mean number of scenes with alcohol per hour, and characteristics of scenes in which alcohol featured. RESULTS: There were 648 separate depictions of alcohol imagery across the week, with an average of one scene every nine minutes. Scenes depicting uncritical imagery outnumbered scenes showing possible adverse health consequences of drinking by 12 to 1. CONCLUSION: The evidence points to a large amount of alcohol imagery incidental to storylines in programming on NZ television. Alcohol is also used in many advertisements to market non-alcohol goods and services. More attention needs to be paid to the extent of alcohol imagery on television from the industry, the government and public health practitioners. Health education with young people could raise critical awareness of the way alcohol imagery is presented on television
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