28 resultados para Outbreak

em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Algal blooms caused by cyanobacteria are characterized by two features with different time scales: one is seasonal outbreak and collapse of a bloom and the other is diurnal vertical migration. Our two-component mathematical model can simulate both phenomena, in which the state variables are nutrients and cyanobacteria. The model is a set of one-dimensional reaction-advection-diffusion equations, and temporal changes of these two variables are regulated by the following five factors: (1) annual variation of light intensity, (2) diurnal variation of light intensity, (3) annual variation of water temperature, (4) thermal stratification within a water column and (5) the buoyancy regulation mechanism. The seasonal change of cyanobacteria biomass is mainly controlled by factors, (1), (3) and (4), among which annual variations of light intensity and water temperature directly affect the maximum growth rate of cyanobacteria. The latter also contributes to formation of the thermocline during the summer season. Thermal stratification causes a reduction in vertical diffusion and largely prevents mixing of both nutrients and cyanobacteria between the epilimnion and the hypolimnion. Meanwhile, the other two factors, (2) and (5), play a significant role in diurnal vertical migration of cyanobacteria. A key mechanism of vertical migration is buoyancy regulation due to gas-vesicle synthesis and ballast formation, by which a quick reversal between floating and sinking becomes possible within a water column. The mechanism of bloom formation controlled by these five factors is integrated into the one-dimensional model consisting of two reaction-advection-diffusion equations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We describe an outbreak of hepatitis A which evolved in Northern Ireland between October 2008 and July 2009, against a background of large concurrent hepatitis A outbreaks in various parts of Europe. Thirty-eight cases were defined as outbreak cases using a stratified case definition; 36 were males with a median age of 29 years and of the 28 males whose sexual orientation was known, 26 were men who have sex with men (MSM). Detailed descriptive epidemiology data collected through standardised questionnaires, together with sequencing of a 289 bp fragment of the VP1/2PA region of the virus, significantly aided the understanding of the spread of the outbreak when non-MSM cases occurred. The sequence of the outbreak strain, genotype IA, was indistinguishable from that involved in a large outbreak in the Czech Republic. Although seeded in a generally susceptible Northern Ireland population, the outbreak remained mostly contained in MSM, showing this sub-population to be the most vulnerable despite ongoing hepatitis A vaccination programmes in genito-urinary medicine clinics.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Strains of many infectious agents differ in fundamental epidemiological parameters including transmissibility, virulence and pathology. We investigated whether genotypes of Mycobacterium bovis (the causative agent of bovine tuberculosis, bTB) differ significantly in transmissibility and virulence, combining data from a nine-year survey of the genetic structure of the M. bovis population in Northern Ireland with detailed records of the cattle population during the same period. We used the size of herd breakdowns as a proxy measure of transmissibility and the proportion of skin test positive animals (reactors) that were visibly lesioned as a measure of virulence. Average breakdown size increased with herd size and varied depending on the manner of detection (routine herd testing or tracing of infectious contacts) but we found no significant variation among M. bovis genotypes in breakdown size once these factors had been accounted for. However breakdowns due to some genotypes had a greater proportion of lesioned reactors than others, indicating that there may be variation in virulence among genotypes. These findings indicate that the current bTB control programme may be detecting infected herds sufficiently quickly so that differences in virulence are not manifested in terms of outbreak sizes. We also investigated whether pathology of infected cattle varied according to M. bovis genotype, analysing the distribution of lesions recorded at post mortem inspection. We concentrated on the proportion of cases lesioned in the lower respiratory tract, which can indicate the relative importance of the respiratory and alimentary routes of infection. The distribution of lesions varied among genotypes and with cattle age and there were also subtle differences among breeds. Age and breed differences may be related to differences in susceptibility and husbandry, but reasons for variation in lesion distribution among genotypes require further investigation. © 2013 Wright et al.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The view that states which claim sovereign status must comply with the responsibility to protect their own citizens is gaining ground in international politics. When a state is unable or unwilling to meet this responsibility, the international community is justified in intervening militarily to end widespread human rights violations. This article argues that a diffuse responsibility to protect, as currently conceived, may have important negative consequences. By using the ongoing tragedy of Darfur as an example, the article argues that the responsibility to protect is reactive and focused on the short term, contributes to the outbreak of violence and perversely provides repressed groups with a further incentive to continue their armed struggle after war breaks out. The tragedy of Darfur shows that effective protection requires case-specific policies aimed at prevention, democratization and economic and political development.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In Northern Ireland of the mid-1990s, many were caught off-guard by the comet-like arrival of a previously unarticulated Ulster Scots identity, replete with its own folk traditions. The article exploits the author’s position as Traditional Arts Officer of the Arts Council of Northern Ireland from 1998 until 2003 to offer an auto-ethnographic reflection on the literature on cultural politics in Northern Ireland since the outbreak of the Troubles, informed by extensive fieldwork with arts administrators and with contemporary Ulster Scots musicians. The article gives a close reading and historical contextualisation of the Ulster-Scots musical revue On Eagle's Wing, which was developed during this period. The article uses the concept of "suture" articulated by Lacan and developed by Laclau, Mouffe, and Žižek to explain both the potential for Ulster Scots culture to enter political discourse out of a seeming vacuum and its subsequent difficulties, offering an original interpretation of the role of culture in the contemporary trajectory of Northern Ireland politics.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Knowledge of the levels of genetic diversity maintained in natural populations can play a central role in conservation programmes, particularly in threatened habitats or species. Fluctuations in population size can lead to loss of variation and, consequently, increase the risk of extinction. We have examined whether such a genetic bottleneck has occurred in populations of two species in the seagrass genus Zostera, which are believed to have been affected by an outbreak of wasting disease at the start of the last century. A test for heterozygote excess at five nuclear microsatellite loci did not suggest the occurrence of a genetic bottleneck, but analysis of seven chloroplast microsatellite loci and sequence data from two regions did suggest a bottleneck in the chloroplast genome. Extremely low levels of between-population diversity suggest that all subpopulations can be treated as a single management unit for each species. Comparable levels of nuclear genetic diversity were found in the three populations of the primarily sexual Zostera marina var. angustifolia studied but a wider range of within-population diversity was found in Zostera noltii, which displays both. sexual and vegetative reproductive strategies. This may be due to an increase in sexual recruitment due to localised fresh water inflow into the study site near to the most diverse population. Such populations should be prioritised as source material for any replanting or remediation due to natural or anthropogenic loss of Zostera beds in the area.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This paper investigates the way in which the ‘problem of poverty’ in Ireland was encountered, constructed and debated by members of the Irish intellectual and political elite in the decades between the Great Famine and the outbreak of the land war in the late 1870s. This period witnessed acute social upheavals in Ireland, from the catastrophic nadir of the Famine, through the much-vaunted economic recovery of the 1850s–1860s, to the near-famine panic of the late 1870s (itself prefigured by a lesser agricultural crisis in 1859–63). The paper focuses on how a particular elite group – the ‘Dublin School’ of political economists and their circle, and most prominently William Neilson Hancock and John Kells Ingram – sought to define and investigate the changing ‘problem’, shape public attitudes towards the legitimacy of welfare interventions and lobby state officials in the making of poor law policy in this period. It suggests that the crisis of 1859–63 played a disproportionate role in the reevaluation of Irish poor relief and in promoting a campaign for an ‘anglicisation’ of poor law measures and practice in Ireland.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The bovine spongiform encephalopathy (BSE) outbreak in the United Kingdom is regarded as one of the worst public policy crises the British government has experienced during the postwar era. In material terms, it has led to the slaughter of 3.3 million cattle and estimated economic losses of £3.7 billion. In administrative terms, the crisis brought about the dissolution of the Ministry of Agriculture, Fisheries and Food. This article examines the istitutional context in which decisions about the scientific evidence on BSE were made. The authors argue that a centralized system in which government agencies control science for government is inherently vulnerable to alliances of experts and interest groups that undermine the credible assessment of public health and safety risks. Specific societal conditions may encourage risk-opportunistic behavior among policy makers that is conducive to delays and inaction until such time as the evidence of a health risk becomes overwhelming.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Rotavirus is the most common etiological cause of acute viral gastroenteritis in infants and young children worldwide, yet its role in the adult population is less well understood. We have recently identified rotavirus as the causative agent of severe diarrhea in adults, specifically in two gastroenteritis outbreaks in separate care for the elderly homes. Strain typing has shown the continued presence of P[8]G1, the emergence of P[8]G9, and the reemergence of P[8]G4. A total of 26 community cases and 6 outbreak cases of rotavirus infection, positive via a molecular screening assay, were subsequently amplified using VP4 and VP7 specific primers (Con2/Con3 and 1A/1B primer sets, respectively). The age range of patients investigated was from

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The outbreak of revolt and revolution in the Middle East has given rise to a re-consideration of threat and security analyses as they pertain to the region and beyond. The resilience of some authoritarian regimes and the rapid collapse of others signal a significant transition within the region to which jihadi Islamist groups form one part of a powerful matrix. This article analyses the part and place of jihadi Islamism and Islamisms more generally in the revolts and revolutions. The article contends that events provide both opportunities and threats in strategies aimed at countering terrorism in the Middle East.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Crowned Harp provides a detailed analysis of policing in Northern Ireland. Tracing its history from 1922, Ellison and Smyth portray the Royal Ulster Constabulary (RUC) as an organisation burdened by its past as a colonial police force. They analyse its perceived close relationship with unionism and why, for many nationalists, the RUC embodied the problem of the legitimacy of Northern Ireland, arguing that decisions made on the organisation, composition and ideology of policing in the early years of the state had consequences which went beyond the everyday practice of policing.

The authors provide an extended discussion of policing after the outbreak of civil unrest in 1969, ask why policing was cast in a paramilitary mould, and look at the use of special constabularies and the way in which the police dealt with social unrest which threatened to break down sectarian divisions. Examining the reorganisations of the RUC in the 1970s and 1980s, Ellison and Smyth focus on the various structural, legal and ideological components, the professionalisation of the force and the development of a coherent, if contradictory, ideology. The analysis of the RUC during this period sheds light on the problematic nature of using the police as a counter insurgency force in a divided society. Perceptions of the police, and the opinions of rank and file members are examined and an assessment is made of the various alternative models of policing, such as community policing and local control. This book offers important lessons about the nature of policing in divided societies.