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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

‘Problems’ of Biological Security : A Foucauldian Discourse Analysis of NATO’s ‘Problem’ Representation of Novel Biological Threats

Nielsby Christensen, Stig January 2022 (has links)
In the current post-pandemic climate biosecurity has emerged as a topic of importance and has further played a dominant role in regard to governance throughout the pandemic. Specifically, NATO’s latest set of policy recommendations to transatlantic biosecurity is the subject of scrutiny in this study, with the findings implying a discursive process of militarization. Guided by Bacchi’s WPR approach (2009), a poststructuralist policy analysis, this study sets out to oust the‘problem’ representations in NATO’s discourse and the logics that underpin them. Additionally, concepts of risk management and the Post-Copenhagen School support the identification of ‘problem’ representations identified aligned with the research purpose. Unexpected the vast body of academic literature ill attempts to produce counter discourse, where this research is embedded. This study argues from the analysis that a discourse originating from the conventionalist security-realm is dominating contemporary conceptions of biosecurity, whilst silencing others. What the NATO report manages to present is a very tangible threat actor with an increasing horizon of possibility of hostile bio-acts, of yet fearsome, unknown character, although what is left opaque is the role of Mother Nature. The study reflects on the motivation of the attempted discursive practice to channel biosecurity into a security-realm, which omits threats of ecological character and solely promoting the existential threat to derive from man. Which finally, is used to justify restrains to public engagement and openness.
102

Modelling the proximal source of intercepted exotic insects

Guichard, Sylvain January 2009 (has links)
Biological invasions are major threats to any nation’s economy and biodiversity. To detect new biological incursions of some species biosecurity agencies deploy pheromone sentinel traps for targeted species at high risk sites such as airports, seaports and transitional facilities. A good example is the gypsy moth surveillance program in New Zealand. Following the detection of an incursion by an unwanted organism, ground-based searches to locate the source can be very expensive, but are essential to identify the introduction pathway and to increase the chances of success eradicating the unwanted organism. In such circumstances, the possibility of better targeting the search for the source of the incursion using a modelling approach is worthy of investigation A stochastic mechanistic model to hindcast moth flight from a recapture location to the release location was developed based on insect behaviour in response to wind and pheromones. The model was composed of two main processes, 1) downwind dispersal, assumed to result from an appetitive behaviour, indicated by an analysis of a previous mark-release-recapture experiment on painted apple moth (Teia anartoides, Walker) and, 2) anemotaxic dispersal inspired by pheromone anemotaxis theory but up-scaled from a fine-scaled behaviour model to a 2 m scale. A genetic algorithm was used to fit some model parameters. A specialised fitness function was developed to allow the genetic algorithm to identify parameters that resulted in models that reflected both the spread and density patterns in the trapping data. The resulting function allowed the stochastic model results to be compared with the inherently stochastic trapping data. The resulting individual based model simulates the spatio-temporal dispersal pattern of painted apple moth recorded during a previous mark-release-recapture experiment. While the proposed model is shown to have limitations with respect to accuracy and precision it is also demonstrated to greatly improve biosecurity incursion response capability, by more efficient targeting of search effort for the proximal source of an incursion.
103

Épidémiologie du syndrome reproducteur et respiratoire porcin dans deux régions de densités porcines différentes au Québec

Lambert, Marie-Ève 06 1900 (has links)
Le virus du syndrome reproducteur et respiratoire porcin (SRRP) est actuellement l’une des principales menaces pour la santé des troupeaux porcins. Les multiples voies de transmission complexifient l’épidémiologie de l’infection et en font une maladie particulièrement difficile à contrôler. L’objectif général de ce projet de recherche était de déterminer les facteurs associés au statut SRRP des sites de production afin de mieux comprendre l’épidémiologie de cette maladie au sein de deux régions du Québec ayant des densités porcines différentes. Les stratégies d’introduction des cochettes de remplacement ont d’abord été examinées. Des lacunes importantes ont été identifiées représentant un risque potentiel pour l’introduction du virus ou pour la recirculation d’une souche endémique au sein d’un troupeau reproducteur. Ainsi, appliquée à titre de stratégie de contrôle, l’acclimatation s’est révélée particulièrement problématique. Les principes de base étaient peu respectés, pouvant donc avoir un impact négatif considérable sur la circulation virale au sein du troupeau et potentiellement sur le voisinage immédiat. La fréquence de plusieurs mesures de biosécurité externe a ensuite été évaluée, permettant d’identifier certains problèmes dont ceux touchant principalement les mesures d’hygiène relatives au protocole d’entrée. Des différences de fréquence entre les régions et les types de production ont également été notées, ce qui peut orienter les interventions de rehaussement. Une classification multivariée a permis de grouper les sites en différents patrons de biosécurité pour constituer par le fait même un index de biosécurité. Cette étape a permis d’évaluer l’association entre certaines caractéristiques de l’élevage et le niveau de biosécurité indiqué par l’index. La distribution géographique des patrons au sein des deux régions, couplée à la détection d’agrégats spatiaux de sites ayant un patron similaire, a également permis de cibler davantage les interventions en fonction de la localisation des sites. Suite à l’investigation du statut SRRP des sites, une prévalence apparente très élevée a été obtenue pour les deux régions, complexifiant le contrôle de la maladie. L’étude de facteurs de risque dans la région de densité modérée a mis en évidence quatre facteurs associés au statut SRRP positif des sites, soit un inventaire important, la proximité du site porcin immédiat, l’absence de douche ainsi que le libre accès au site par l’équarrisseur. Une action préventive intégrant des mesures de biosécurité spécifiques peut donc être entreprise directement à la ferme au regard des deux derniers facteurs. Le fait d’utiliser un index de biosécurité plutôt que des mesures de biosécurité spécifiques a également été évalué. Les résultats ne supportent pas l’index global dans l’évaluation de l’association entre la biosécurité et le statut SRRP des sites de production. Finalement, la corrélation entre les distances génétique, euclidienne et temporelle des souches de SRRP, considérant également l’appartenance au même ou à des propriétaires différents, a été évaluée au sein de la région de haute densité. Une corrélation positive entre la distance génétique et euclidienne observée jusqu’à 5 km a souligné l’importance de la propagation régionale impliquant les aérosols, les insectes, d’autres espèces animales ou les objets inanimés. De plus, les souches génétiquement similaires appartenaient davantage à des sites ayant le même propriétaire, ce qui sous-tend des mécanismes de transmission impliquant une source commune d’animaux, d’employés, d’équipement, voire de véhicules. / The economic impact of porcine reproductive and respiratory syndrome virus (PRRSV) on swine industry compelled us to improve our knowledge on the epidemiology of the disease in a perspective of prevention. On-farm and regional management of the disease is complex due to the numerous pathways of transmission of the virus. The main objective of this project was to determine factors associated with PRRS status of production sites in two areas of different swine density in Quebec to improve our knowledge on the epidemiology of PRRS. Gilt replacement strategies were first investigated and practices potentially at risk for PRRSV introduction or recirculation into the sow herd were identified. Acclimatization, which is reported to be an effective strategy to control PRRSV within a herd, was the most common but was the worst applied strategy in the participating herds. Basic principles were not respected which could enhance PRRSV circulation into the sow herd and potentially in the neighbourhood. The frequency of different biosecurity practices was also examined and led to the identification of some shortcomings, mainly related to the entrance protocol for people; these should be addressed at the farm level before implementing any PRRS regional control. Differences of frequency were observed between regions and production types, thus using this information could help targeting future intervention of biosecurity enhancement. A biosecurity index was developed by grouping sites in different biosecurity patterns using a multivariable technique of classification. This allowed the identification of associations between biosecurity index and characteristic of sites. The geographical distribution of biosecurity patterns among each region combined with the detection of cluster of sites having similar pattern would help to target intervention based on site location. PRRS status of sites was determined and a high apparent prevalences of infected sites were obtained in both regions which will complicate PRRS management. In the moderate density area, four variables were associated with PRRS positive status: high inventory, proximity to the closest pig site, absence of shower and free access to the site by rendering trucks. Whereas the first two factors are non modifiable characteristics of site, the other ones can be directly managed on the site by biosecurity. The impact of using a biosecurity index instead of specific biosecurity variables was also evaluated. Results do not support the use of a global index to assess association between biosecurity and PRRS status. Finally, the correlation among genetic, Euclidean and temporal distances and ownership of PRRSV strains was assessed in the high density area. Positive correlation between genetic distance and ownership suggests either common sources of animals or semen, employees, technical services or vehicles. A positive correlation was also obtained between genetic and Euclidean distances up to 5 km, suggesting the importance of mechanisms involved in area spread such as aerosols, insects, others animal species or fomites.
104

La protection de la vie privée au temps de la biosécurité

Déziel, Pierre-Luc 03 1900 (has links)
Cette thèse s’intéresse à la protection de la vie privée informationnelle dans le contexte de la biosécurité. La biosécurité se définit comme le processus qui vise à prendre en charge, dans une optique de sécurité nationale, les menaces et dangers que représentent les épidémies de maladies infectieuses pour la santé des populations humaines et la sécurité de l’État. Notre projet remet en question l’idée selon laquelle la conduite des activités de surveillance de la santé publique implique nécessairement une diminution de la protection offerte aux renseignements personnels sur la santé. Nos recherches tendent à démontrer que la conciliation de la surveillance de la santé et la protection de la vie privée est non seulement possible, mais qu’elle est surtout nécessaire. Nous portons plus précisément notre attention sur le cas de la collecte et de l’utilisation de renseignements dépersonnalisés sur la santé par les systèmes de surveillance syndromique. Bien calibrée et soigneusement réglementée, cette forme novatrice et particulière de surveillance offrirait le double avantage de réduire les risques d’atteintes à la vie privée des individus et d’augmenter de manière considérable l’efficacité des capacités étatiques en matière de détection des épidémies. / This thesis focuses on the protection of privacy in the context of biosecurity. Biosecurity is concerned with the threats that epidemics of infectious diseases present to public health and national security. The main goal of my thesis is to challenge the idea that conducting meaningful public health surveillance necessarily implies that the scope of the legal protection given to personal health information has to be reduced. My research demonstrates that, given certain conditions, a public health surveillance conducted with carefully configured syndromic surveillance systems operating with de-identified health data would increase both the efficiency of surveillance in terms of its capacity to detect emerging epidemics and the level of informational privacy of the patients.
105

Épidémiologie du syndrome reproducteur et respiratoire porcin dans deux régions de densités porcines différentes au Québec

Lambert, Marie-Ève 06 1900 (has links)
No description available.
106

Le double visage des inventions biotechnologiques, une source potentielle de risques majeurs / The double face of biotechnological inventions, a potential source of major risks

Laporte, Sylvie 19 October 2011 (has links)
Les inventions biotechnologiques ont un double visage, une face bienveillante et une face terrifiante, chacune source potentielle de risques majeurs. Comment les contrôler et les réguler ? La recrudescence des catastrophes majeures (crises sanitaires) liées à l’usage de produits biotechnologiques, d’une part, puis l’échec à l’adoption d’un protocole de vérification à la Convention d’interdiction des armes biologiques suivi de l’émergence de nombreuses publications à risques dans le domaine des biotechnologies, d’autre part, démontrent l’omniprésence et la transversalité de cette problématique. Par leur essence duale, les biotechnologies appellent des solutions globales. La voie d’une gestion cohérente semble s’ouvrir au travers d’un corps de règle prenant tous ces paramètres en considération, les risques majeurs. L’avantage de cette législation, si elle admet une modification préalable de la nomenclature des risques majeurs en y intégrant les risques liés aux conflits, reposera sur sa globalité et sur la responsabilisation de tous. Face à une menace biotechnologique qui est perçue comme dominante dans les années à venir, l’émerge d’un ordre public mondial favorable à un accroissement de la responsabilité des Etats à l’égard de la sécurité humaine serait souhaitable. Le but de toute institution étatique étant de garantir à ses ressortissants leur sécurité et leur sûreté quelles que soient les circonstances, cet ordre public pourrait trouver ses bases au sein des réglementations relatives aux droits de l’homme et au droit de l’environnement ; réglementations déjà émancipées de la distinction entre situations de paix, de crises ou de conflits / The biotechnological inventions have a double face, a kindly face and a terrifying face, each potential source of major risks. How to control them and to regulate them? The outbreak of the major disasters (sanitary crisis) bound to biotechnological products, on one hand, the failure to the adoption of a Protocol to the Biological Weapon Convention, followed by the emergence of numerous publications at risks in the field of biotechnology, on the other hand, demonstrate the omnipresence and the transverse character of this problem. By their duality, biotechnologies need global solutions. The way of a coherent management seems to open through a body of rule considering all these parameters, the major risks. The advantage of this legislation, if it admits a preliminary modification of the list of the major risks by integrating the risks connected to the conflicts, will be based on its global aspect and everyone’s responsibility. In front of biotechnological threat, which is perceived as dominant in the years to come, an emergent world law and order favourable to an increase of the responsibility of States towards the human safety would be desirable. The purpose of any state institution is the guarantee of Nationals safety, whatever circumstances are, this law and order could find its bases within the regulations relative to human rights and to environmental law; these regulations are already indifferent to the distinction between situations of peace, crisis or conflicts
107

The importance of selective filters on vessel biofouling invasion processes

Schimanski, Kate Bridget January 2015 (has links)
The spread of exotic species is considered to be one of the most significant threats to ecosystems and emphasises the need for appropriate management interventions. The majority of marine non-indigenous species (NIS) are believed to have been introduced via ship biofouling and their domestic spread continues to take place via this mechanism. In some countries, biosecurity systems have been developed to prevent the introduction of NIS through biofouling. However, implementing biosecurity strategies is difficult due to the challenges around identifying high-risk vectors. Reliable predictors of risk have remained elusive, in part due to a lack of scientific knowledge. Nonetheless, invasion ecology is an active scientific field that aims to build this knowledge. Propagule pressure is of particular interest in invasion ecology as it describes the quantity and quality of the propagules introduced into a recipient region and is considered to be an important determinant in the successful establishment of NIS. Environmental history affects health and reproductive output of an organism and, therefore, it is beneficial to examine this experimentally in the context of biofouling and propagule pressure. The aim of this thesis was to examine how voyage characteristics influence biofouling recruitment, survivorship, growth, reproduction and offspring performance through the ship invasion pathway. This was to provide fundamental knowledge to assist managers with identifying high-risk vessels that are likely to facilitate the introduction or domestic spread of NIS, and to understand the processes affecting biofouling organisms during long-distance dispersal events. Chapter One provides an introduction to the issues addressed in this thesis. Each data chapter (Chapters Two – Five) then focused on a stage of the invasion process and included field experiments using a model organism, Bugula neritina. Finally, Chapter Six provides a summary of key findings, discussion and the implications to biosecurity management. Throughout this thesis, the effect of donor port residency period on the success of recruits was highlighted. Chapter Two focused on recruitment in the donor region. As expected, recruitment increased with residency period. Importantly, recruitment occurred every day on vulnerable surfaces, therefore, periods as short as only a few days are able to entrain recruits to a vessel hull. The study presented in Chapter Three showed that there was high survivorship of B. neritina recruits during 12 translocation scenarios tested. In particular, the juvenile short-residency recruits (1-8 days) survived voyages of 8 days at a speed of 18 knots; the longest and fastest voyage simulated. Interestingly, variation in voyage speed and voyage duration had no effect on the survivorship of recruits, but did have legacy effects on post-voyage growth. Again, B. neritina which recruited over very short residency periods of 1 day continued to perform well after translocation and had the highest level of reproductive output after the voyage scenarios (Chapter Four). Recruits that were older (32-days) and reproductively mature at the commencement of the scenarios failed to release any propagules. Even though the number of ‘at sea’ and ‘port residency’ days were equal, reproductive output was higher after short and frequent voyages than after long and infrequent voyages. Finally, the study presented in Chapter Five examined transgenerational effects of B. nertina. Results showed that although the environmental history of the parent colony had a carry-over effect on offspring performance, it was the offspring environment that was a stronger determinant of success (measured by reproductive output and growth). Although cross-vector spread is possible (i.e. parent and offspring both fouling an active vessel), offspring released from a hull fouling parent into a recipient environment will perform better. In combination, these studies have provided new insights into NIS transport via vessel biofouling. Although shipping pathways are dynamic and complex, these results suggest that juvenile stages that recruit over short residency periods and are then translocated on short voyages, may pose a higher risk for NIS introduction than originally assumed. This has implications for marine biosecurity management as short residency periods are common and short, frequent voyages are typical of domestic vessel movements which are largely unmanaged.
108

<b>REGIONAL DISTRIBUTION OF WOODY INVASIVES AND THE RESPONSE OF PLANT COMMUNITIES TO INVASIVE CONTROL THROUGH GOVERNMENT COST SHARE PROGRAMS</b>

Aubrey W Franks (18429756) 24 April 2024 (has links)
<p dir="ltr">Non-native biological invasions are one of the leading concerns for global biodiversity. The establishment of invasive species reduces local biodiversity, shifts species composition, changes successional trajectories, and alters ecosystem functions. This thesis examines two aspects of invasive plants: (1) the distribution and the most important climatic and anthropogenic drivers of invasive trees across the eastern United States, and (2) an evaluation of invasive plant removal and herbaceous recovery from a government cost-share program that provides financial support for invasive plant management by private landowners.</p><p><br></p><p dir="ltr">Our first study focused on identifying the distribution of invasive trees, and the factors associated with their distribution. This is essential to predicting spread and planning subsequent management. Using USDA Forest Inventory Analysis (FIA) data and random forest modeling, we examined the distribution, and variables associated with the distribution, of invasive tree species. Invasive trees were found in 10,511 out of 299,387 FIA plots. Invasive species basal area and density (trees per ha; TPH) were highest within the central and southern Appalachian Mountains, Michigan, the Northeast, and the southern Coastal Plain of the United States. A random forest model of invasive species basal area (R<sup>2 </sup>= 0.47, RMSE = 0.47) and density (R<sup>2</sup>=0.46, RMSE=0.50) vs. environmental variables found that both invasive basal area and density were most strongly associated with human footprint, followed by various climatic variables. An equivalent model of native tree basal (R<sup>2</sup>=0.53, RMSE=9.25) and TPH (R<sup>2</sup>=0.47, RMSE=8.64) found that native tree basal area and density were most strongly associated with aridity followed by various climatic variables. As human footprint increased, invasive tree basal area and density increased. These results suggest that the distribution of invasive trees is reliant on human alterations to forests.</p><p><br></p><p dir="ltr">Our second study focused on Environmental Quality Incentives Program (EQIP), a federal cost-share program that has provided $25 billion of financial assistance to farmers and non-industrial private forest owners. Few studies have examined whether this program facilitates the recovery of the herbaceous layer while decreasing the dominance of invasive plant species. We surveyed the herbaceous layer of EQIP-treated and untreated (reference) forests across three physiographic regions of Indiana. Using non-metric multidimensional scaling (NMDS) ordination and linear mixed effects models, we evaluated the species composition, richness, diversity, evenness, floristic quality index, and herbaceous-layer cover of EQIP and reference sites. We also used linear mixed models to evaluate how EQIP site treatment affected the diversity of native plant species. Sites treated with EQIP contracts typically had significantly higher native species richness, Shannon’s diversity, and floristic quality than reference sites. There were significant separations in species composition between EQIP treated and reference forests state-wide and in the southern non-glaciated region of Indiana, although composition overlapped between EQIP and reference forests. Our study suggests that EQIP-funded treatments promote increased species richness and diversity. However, the persistent overlap in species composition we observed may signify biotic homogenization due to a long-shared history of anthropogenic disturbances between EQIP and reference sites. Therefore, active restoration of the herbaceous layer might be needed to allow a full recovery after invasive removal.</p>

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